TY - JOUR
A1 - Kürschner, Tobias
A1 - Scherer, Cédric
A1 - Radchuk, Viktoriia
A1 - Blaum, Niels
A1 - Kramer-Schadt, Stephanie
T1 - Movement can mediate temporal mismatches between resource availability and biological events in host-pathogen interactions
JF - Ecology and evolution
N2 - Global change is shifting the timing of biological events, leading to temporal mismatches between biological events and resource availability. These temporal mismatches can threaten species' populations. Importantly, temporal mismatches not only exert strong pressures on the population dynamics of the focal species, but can also lead to substantial changes in pairwise species interactions such as host-pathogen systems. We adapted an established individual-based model of host-pathogen dynamics. The model describes a viral agent in a social host, while accounting for the host's explicit movement decisions. We aimed to investigate how temporal mismatches between seasonal resource availability and host life-history events affect host-pathogen coexistence, that is, disease persistence. Seasonal resource fluctuations only increased coexistence probability when in synchrony with the hosts' biological events. However, a temporal mismatch reduced host-pathogen coexistence, but only marginally. In tandem with an increasing temporal mismatch, our model showed a shift in the spatial distribution of infected hosts. It shifted from an even distribution under synchronous conditions toward the formation of disease hotspots, when host life history and resource availability mismatched completely. The spatial restriction of infected hosts to small hotspots in the landscape initially suggested a lower coexistence probability due to the critical loss of susceptible host individuals within those hotspots. However, the surrounding landscape facilitated demographic rescue through habitat-dependent movement. Our work demonstrates that the negative effects of temporal mismatches between host resource availability and host life history on host-pathogen coexistence can be reduced through the formation of temporary disease hotspots and host movement decisions, with implications for disease management under disturbances and global change.
KW - classical swine fever
KW - dynamic landscapes
KW - global change
KW - host– pathogen dynamics
KW - individual‐ based model
KW - movement ecology
Y1 - 2021
U6 - https://doi.org/10.1002/ece3.7478
SN - 2045-7758
VL - 11
IS - 10
SP - 5728
EP - 5741
PB - Wiley
CY - Hoboken
ER -
TY - JOUR
A1 - Gamage, Dilrukshi
A1 - Staubitz, Thomas
A1 - Whiting, Mark
T1 - Peer assessment in MOOCs
BT - Systematic literature review
JF - Distance education
N2 - We report on a systematic review of the landscape of peer assessment in massive open online courses (MOOCs) with papers from 2014 to 2020 in 20 leading education technology publication venues across four databases containing education technology-related papers, addressing three research issues: the evolution of peer assessment in MOOCs during the period 2014 to 2020, the methods used in MOOCs to assess peers, and the challenges of and future directions in MOOC peer assessment. We provide summary statistics and a review of methods across the corpus and highlight three directions for improving the use of peer assessment in MOOCs: the need for focusing on scaling learning through peer evaluations, the need for scaling and optimizing team submissions in team peer assessments, and the need for embedding a social process for peer assessment.
KW - MOOC
KW - peer assessment
KW - peer evaluation
KW - peer review
KW - literature review
KW - social interaction
Y1 - 2021
U6 - https://doi.org/10.1080/01587919.2021.1911626
SN - 0158-7919
SN - 1475-0198
VL - 42
IS - 2
SP - 268
EP - 289
PB - Routledge, Taylor & Francis Group
CY - Abingdon
ER -
TY - JOUR
A1 - Monod, Emmanuel
A1 - Köster, Antonia
A1 - Joyce, Elisabeth
A1 - Khalil, Sabine
A1 - Korotkova, Nataliia
T1 - Digital transformation consulting
BT - toward a human-technology performance model digital transformat
JF - Academy of management proceedings
N2 - As the focus on digital transformation and its unexplored opportunities is prospering, consulting firms have also turned their attention to it. Despite this increased attention, digital transformation project failure rate remains high, thereby reaffirming the “IT productivity paradox” or “AI productivity paradox. The purpose of this paper is to holistically scrutinize the current approach of digital transformation consulting. A deductive qualitative study draws upon the Human Technology Performance model to elucidate papers on digital transformation published by four major management consulting firms in 2014-2019. Whereas the focus on customer-centricity and some measures of corporate performance is prominent in the consulting approaches, the study results have revealed several “blind spots” that are still either neglected or poorly covered. Three main blind spots are particularly prominent from the analysis. First of all, consulting firms often apply a “one size fits all” approach, thereby neglecting contextual factors, such as age, size, or industry. Secondly, they neglect process level in the return on investment of IT. Thirdly, the suitability of IS development methods remains poorly considered. Hence, the paper argues that, while consulting firms purport to support digital transformation exigences and efforts, they, in fact, adhere to traditional approaches to business consulting.
Y1 - 2021
U6 - https://doi.org/10.5465/AMBPP.2021.12737abstract
SN - 0065-0668
IS - 1
PB - Academy of Management
CY - Briarcliff Manor
ER -
TY - JOUR
A1 - Bender, Benedict
A1 - Körppen, Tim
T1 - Data Warehouse, Data Lake oder Data Platform
BT - eine Übersicht analyseorientierter Datenhaltungslösungen
JF - ERP-Management : Auswahl, Einführung und Betrieb von ERP-Systemen
N2 - Die Digitalisierung des deutschen Mittelstandes schreitet weiterhin schleppend voran. So verfügt zwar ein wachsender Teil dieser Unternehmen über vereinzelte Informations- und Kommunikationssysteme, die zielführende Vernetzung und Integration dieser Systeme stellt jedoch weiterhin eine große Aufgabe dar [1]. Besonders vor dem Hintergrund wachsender Bedürfnisse für Informationen und Transparenz sehen sich Unternehmen zunehmend mit der analyseorientierten Nutzbarmachung der Unternehmensdaten konfrontiert [2].
Y1 - 2021
UR - https://www.wiso-net.de/document/ERP__ffa066cd51fc1133cb63f47337a74ecee09b97a2
SN - 1860-6725
VL - 17
IS - 6
SP - 34
EP - 37
PB - GITO mbH Verlag
CY - Berlin
ER -
TY - JOUR
A1 - Ullrich, André
A1 - Teichmann, Malte
A1 - Gronau, Norbert
T1 - Fast trainable capabilities in software engineering-skill development in learning factories
JF - Ji suan ji jiao yu = Computer Education / Qing hua da xue
N2 - The increasing demand for software engineers cannot completely be fulfilled by university education and conventional training approaches due to limited capacities. Accordingly, an alternative approach is necessary where potential software engineers are being educated in software engineering skills using new methods. We suggest micro tasks combined with theoretical lessons to overcome existing skill deficits and acquire fast trainable capabilities. This paper addresses the gap between demand and supply of software engineers by introducing an actionoriented and scenario-based didactical approach, which enables non-computer scientists to code. Therein, the learning content is provided in small tasks and embedded in learning factory scenarios. Therefore, different requirements for software engineers from the market side and from an academic viewpoint are analyzed and synthesized into an integrated, yet condensed skills catalogue. This enables the development of training and education units that focus on the most important skills demanded on the market. To achieve this objective, individual learning scenarios are developed. Of course, proper basic skills in coding cannot be learned over night but software programming is also no sorcery.
KW - learning factory
KW - programming skills
KW - software engineering
KW - training
Y1 - 2021
U6 - https://doi.org/10.16512/j.cnki.jsjjy.2020.12.002
SN - 1672-5913
IS - 12
SP - 2
EP - 10
PB - [Verlag nicht ermittelbar]
CY - Bei jing shi
ER -
TY - JOUR
A1 - Apelt, Maja
A1 - Binder, Beate
A1 - Kuster, Friederike
T1 - Einleitung
JF - Feministische Studien
Y1 - 2021
U6 - https://doi.org/10.1515/fs-2021-0027
SN - 0723-5186
VL - 39
IS - 2
SP - 197
EP - 201
PB - De Gruyter Oldenbourg
CY - Berlin
ER -
TY - JOUR
A1 - Lass, Sander
A1 - Jonas-Kops, Jörg E.
T1 - Assisted Reality - mehr als nur das Smart Glass
JF - Fabriksoftware : die digitale Fabrik realisieren
N2 - Der nutzbringenden Einsatz einer Datenbrille besteht nicht nur aus der Brille selbst. Die potenzielle ressourcenschonende Assistenz bei der Abarbeitung von komplexen Workflows bedarf eine ausreichende Integration in die Anwendungssystemlandschaft. Implikation sind demnach zwei Hauptelemente: die Brille selbst und die Integrationssoftware. Beide Komponenten sind in geeigneter Form auszulegen und auf die intendierten Anwendungsfälle zu konfigurieren. Dieser Beitrag fasst die Erfahrungen aus zahlreichen Projekten zusammen und liefert einen Überblick über die Herausforderungen bei AR-Einführungen.
Y1 - 2021
UR - https://www.wiso-net.de/document/PPS__4ae320609d0d4479d1887da5f48ea6c91f3b9041
SN - 2569-7692
VL - 26
IS - 2
SP - 27
EP - 29
PB - GITO mbH - Verlag für Industrielle Informationstechnik und Organisation
CY - Berlin
ER -
TY - JOUR
A1 - Lass, Sander
T1 - ControlCenter 4.0
BT - erleichterte Inbetriebnahme und Steuerung der Simulationsumgebung
JF - Fabriksoftware : die digitale Fabrik realisieren
Y1 - 2021
SN - 2569-7692
VL - 26
IS - 2
SP - 30
EP - 31
PB - GITO mbH - Verlag für Industrielle Informationstechnik und Organisation
CY - Berlin
ER -
TY - JOUR
A1 - Körppen, Tim
A1 - Ullrich, André
A1 - Bertheau, Clementine
T1 - Durchblick statt Bauchgefühl – Transformation zur Data-Driven Organization
JF - Wirtschaftsinformatik & Management
N2 - Um in der digitalisierten Wirtschaft mitzuspielen, müssen Unternehmen, Markt und insbesondere Kunden detailliert verstanden werden. Neben den „Big Playern“ aus dem Silicon Valley sieht der deutsche Mittelstand, der zu großen Teilen noch auf gewachsenen IT-Infrastrukturen und Prozessen agiert, oft alt aus. Um in den nächsten Jahren nicht gänzlich abgehängt zu werden, ist ein Umbruch notwendig. Sowohl Leistungserstellungsprozesse als auch Leistungsangebot müssen transparent und datenbasiert ausgerichtet werden. Nur so können Geschäftsvorfälle, das Marktgeschehen sowie Handeln der Akteure integrativ bewertet und fundierte Entscheidungen getroffen werden. In diesem Beitrag wird das Konzept der Data-Driven Organization vorgestellt und aufgezeigt, wie Unternehmen den eigenen Analyticsreifegrad ermitteln und in einem iterativen Transformationsprozess steigern können.
Y1 - 2021
U6 - https://doi.org/10.1365/s35764-021-00370-7
SN - 1867-5905
VL - 13
IS - 6
SP - 452
EP - 459
PB - Springer Gabler
CY - Wiesbaden
ER -
TY - JOUR
A1 - Ullrich, Andre
A1 - Bertheau, Clementine
A1 - Wiedmann, Miriam
A1 - Sultanow, Eldar
A1 - Körppen, Tim
A1 - Bente, Stefan
T1 - Roles, tasks and skills of the enterprise architect in the VUCA world
JF - 2021 IEEE 25th International Enterprise Distributed Object Computing Conference Workshops : EDOCW 2021 : 25-29 October 2021, Gold Coast, Australia : proceedings
N2 - For the last 20 years, enterprise architecture management (EAM) was primarily an instrument for harmonizing and consolidating IT landscapes and is lived as a transformation and governance discipline. It, however, is rather related to IT strategy than aligned to the actual corporate strategy and the work of the enterprise architect is characterized by tasks like prescribing, monitoring, documenting, and controlling. As digital transformation continues apace, companies are facing new challenges that lead to a volatile, uncertain, complex, and ambiguous (VUCA) world. To face these challenges, vision, understanding, clarity and agility allow to anticipative and implement necessary changes. This, of course, has implications for the role of the enterprise architect. S/he needs to start actively supporting innovation and taking more of an advisory role instead of just being driven by the current state of the enterprise architecture. This paper investigates the role of the enterprise architect in the VUCA world. Based on current literature and expert interviews, a survey was conducted among consultants who work as (or with) enterprise architects. Survey results include the evaluation of statements on current tasks of enterprise architects, their influence on projects and companies as well as future requirements on the roles of the enterprise architect. The results from the survey were synthesized with the findings from literature to derive the roles, tasks and skills of enterprise architect in the VUCA world.
KW - enterprise architecture management
KW - skills
KW - roles
KW - enterprise architect
KW - VUCA
Y1 - 2021
SN - 978-1-6654-4488-0
U6 - https://doi.org/10.1109/EDOCW52865.2021.00057
SP - 261
EP - 270
PB - IEEE
CY - Piscataway
ER -
TY - JOUR
A1 - Gautam, Khem Raj
A1 - Zhang, Guoqiang
A1 - Landwehr, Niels
A1 - Adolphs, Julian
T1 - Machine learning for improvement of thermal conditions inside a hybrid ventilated animal building
JF - Computers and electronics in agriculture : COMPAG online ; an international journal
N2 - In buildings with hybrid ventilation, natural ventilation opening positions (windows), mechanical ventilation rates, heating, and cooling are manipulated to maintain desired thermal conditions. The indoor temperature is regulated solely by ventilation (natural and mechanical) when the external conditions are favorable to save external heating and cooling energy. The ventilation parameters are determined by a rule-based control scheme, which is not optimal. This study proposes a methodology to enable real-time optimum control of ventilation parameters. We developed offline prediction models to estimate future thermal conditions from the data collected from building in operation. The developed offline model is then used to find the optimal controllable ventilation parameters in real-time to minimize the setpoint deviation in the building. With the proposed methodology, the experimental building's setpoint deviation improved for 87% of time, on average, by 0.53 degrees C compared to the current deviations.
KW - Animal building
KW - Natural ventilation
KW - Automatically controlled windows
KW - Machine learning
KW - Optimization
Y1 - 2021
U6 - https://doi.org/10.1016/j.compag.2021.106259
SN - 0168-1699
SN - 1872-7107
VL - 187
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Hölzle, Katharina
A1 - Björk, Jennie
A1 - Boer, Harry
T1 - Light at the end of the tunnel
JF - Creativity and innovation management
Y1 - 2021
U6 - https://doi.org/10.1111/caim.12427
SN - 0963-1690
SN - 1467-8691
VL - 30
IS - 1
SP - 3
EP - 5
PB - Wiley-Blackwell
CY - Oxford [u.a.]
ER -
TY - JOUR
A1 - Adam, Jan P.
A1 - Hahn, Michelle
A1 - Hölscher, Ines
A1 - Höschel, Heike
A1 - Janzen, Stella
A1 - Kögel, Lukas
T1 - Automatisierung von Routinetätigkeiten im öffentlichen Dienst
JF - Verwaltung & Management
N2 - Auf Basis einer Umfrage unter 300 Beschäftigten im öffentlichen Dienst untersucht dieser Beitrag, welche möglichen Auswirkungen die Digitale Transformation auf das Tätigkeitsprofil von Mitarbeiterinnen und Mitarbeitern im öffentlichen Sektor haben kann. Zum einen finden sich erste Hinweise auf signifikante Effizienzpotenziale durch Automatisierung im öffentlichen Sektor. Zum anderen wird deutlich, dass die Mitarbeiterinnen und Mitarbeiter dieser Entwicklung mehrheitlich positiv gegenüberstehen und sie aktiv an der Verbesserung von Dienstleistungen mitwirken wollen. Aus diesen Erkenntnissen können zahlreiche Handlungsimplikationen für Veränderungsprojekte in der Praxis abgeleitet werden. Gleichzeitig ruft dieser Beitrag dazu auf, die Folgen der Digitalen Transformation für Mitarbeiterinnen und Mitarbeiter noch besser zu erforschen.
Y1 - 2021
U6 - https://doi.org/10.5771/0947-9856-2021-1-39
SN - 0947-9856
SN - 2942-352X
VL - 27
IS - 1
SP - 39
EP - 48
PB - Nomos
CY - Baden-Baden
ER -
TY - JOUR
A1 - Caliendo, Marco
A1 - Tübbicke, Stefan
T1 - Design and effectiveness of start-up subsidies
BT - evidence from a policy reform in Germany
JF - Economic analysis and policy
N2 - While a growing body of literature finds positive impacts of Start-Up Subsidies (SUS) on labor market outcomes of participants, little is known about how the design of these programs shapes their effectiveness and hence how to improve policy. As experimental variation in program design is unavailable, we exploit the 2011 reform of the current German SUS program for the unemployed which strengthened caseworkers' discretionary power, increased entry requirements and reduced monetary support. We estimate the impact of the reform on the program's effectiveness using samples of participants and non-participants from before and after the reform. To control for time-constant unobserved heterogeneity as well as differential selection patterns based on observable characteristics over time, we combine Difference-in-Differences with inverse probability weighting using covariate balancing propensity scores. Holding participants' observed characteristics as well as macroeconomic conditions constant, the results suggest that the reform was successful in raising employment effects on average. As these findings may be contaminated by changes in selection patterns based on unobserved characteristics, we assess our results using simulation-based sensitivity analyses and find that our estimates are highly robust to changes in unobserved characteristics. Hence, the reform most likely had a positive impact on the effectiveness of the program, suggesting that increasing entry requirements and reducing support increased the program's impacts while reducing the cost per participant. (C) 2021 Economic Society of Australia, Queensland. Published by Elsevier B.V. All rights reserved.
KW - start-up subsidies
KW - institutions
KW - policy reform
KW - difference-in-differences
Y1 - 2021
U6 - https://doi.org/10.1016/j.eap.2021.02.015
SN - 0313-5926
VL - 70
SP - 333
EP - 340
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Sonnentag, Michael
T1 - Fluggastrechte bei Buchung eines Firmentarifs
BT - VO (EG) Nr. 261/2004 (Fluggastrechte-VO) Art. 3 III
JF - Neue juristische Wochenschrift
N2 - Ein vergünstigter Tarif, den ein Luftfahrtunternehmen für Geschäftsreisen von Mitarbeitern eines Unternehmens gewährt, das eine entsprechende Rahmenvereinbarung geschlossen hat, ist im Sinne des Art. 3 III 1 Fluggastrechte-VO für die Öffentlichkeit verfügbar.
Y1 - 2021
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-B-2021-S-3659-N-1
SN - 0341-1915
VL - 74
IS - 50
SP - 3659
EP - 3663
PB - C.H. Beck
CY - München
ER -
TY - JOUR
A1 - Sonnentag, Michael
A1 - Bischof, Manuela
T1 - ZR-Anfängerhausarbeit zum BGB-AT und Schuldrecht
BT - der verflixte Schallplattenkauf
JF - Juristische Ausbildung
N2 - Die Hausarbeit beinhaltet Probleme des Allgemeinen Teils des BGB sowie des Schuldrechts. Sie wurde in geringfügig abgewandelter Form als Ferienhausarbeit für Anfänger im Bürgerlichen Recht im Wintersemester 2018/2019 an der Universität Würzburg gestellt. Der Notendurchschnitt lag bei 6,25 Punkten, die Hausarbeit wurde von 18,75 % der Studierenden nicht bestanden.
Y1 - 2021
U6 - https://doi.org/10.1515/jura-2020-2510
SN - 0170-1452
SN - 1612-7021
VL - 43
IS - 11
SP - 1346
EP - 1356
PB - De Gruyter
CY - Berlin
ER -
TY - JOUR
A1 - Navarro, Marisa
A1 - Orejas, Fernando
A1 - Pino, Elvira
A1 - Lambers, Leen
T1 - A navigational logic for reasoning about graph properties
JF - Journal of logical and algebraic methods in programming
N2 - Graphs play an important role in many areas of Computer Science. In particular, our work is motivated by model-driven software development and by graph databases. For this reason, it is very important to have the means to express and to reason about the properties that a given graph may satisfy. With this aim, in this paper we present a visual logic that allows us to describe graph properties, including navigational properties, i.e., properties about the paths in a graph. The logic is equipped with a deductive tableau method that we have proved to be sound and complete.
KW - Graph logic
KW - Algebraic methods
KW - Formal modelling
KW - Specification
Y1 - 2021
U6 - https://doi.org/10.1016/j.jlamp.2020.100616
SN - 2352-2208
SN - 2352-2216
VL - 118
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Neuharth, Derek
A1 - Brune, Sascha
A1 - Glerum, Anne
A1 - Morley, Chris K.
A1 - Yuan, Xiaoping
A1 - Braun, Jean
T1 - Flexural strike-slip basins
JF - Geology : a venture in earth science reporting / the Geological Society of America
N2 - Strike-slip faults are classically associated with pull-apart basins where continental crust is thinned between two laterally offset fault segments. We propose a subsidence mechanism to explain the formation of a new type of basin where no substantial segment offset or synstrike-slip thinning is observed. Such "flexural strike-slip basins" form due to a sediment load creating accommodation space by bending the lithosphere. We use a two-way coupling between the geodynamic code ASPECT and surface-processes code FastScape to show that flexural strike-slip basins emerge if sediment is deposited on thin lithosphere close to a strike slip fault. These conditions were met at the Andaman Basin Central fault (Andaman Sea, Indian Ocean), where seismic reflection data provide evidence of a laterally extensive flexural basin with a depocenter located parallel to the strike-slip fault trace.
Y1 - 2021
U6 - https://doi.org/10.1130/G49351.1
SN - 0091-7613
SN - 1943-2682
VL - 50
IS - 3
SP - 361
EP - 365
PB - American Institute of Physics
CY - Boulder
ER -
TY - JOUR
A1 - Lettl, Tobias
T1 - Beweislast; Zurechnung kartellrechtswidrigen Verhaltens einer Gesellschaft; Stimmrecht; bestimmender Einfluss
JF - Entscheidungsanmerkungen zum Wirtschafts- und Bankrecht
Y1 - 2021
UR - https://www.wiso-net.de/document/WUB__0333106108e4bf7b2e7db8349f611358533ed772
SN - 2364-7310
VL - 37
IS - 4
SP - 185
EP - 189
PB - Otto Schmidt
CY - Köln
ER -
TY - JOUR
A1 - Lettl, Tobias
T1 - Einstufung eines Privatkaufs als gewerblich
BT - BGB (F. bis 31.12.2017) §§ 13, 14 I, 437 Nr. 1, 439 II, 439 III; BGB § 474 I 1
JF - Neue juristische Wochenschrift
Y1 - 2021
UR - https://beck-online.beck.de/Bcid/Y-300-Z-NJW-B-2021-S-2277-N-1
SN - 0341-1915
VL - 74
IS - 31
SP - 2277
EP - 2280
PB - C.H. Beck
CY - München
ER -
TY - JOUR
A1 - Naser, Eyad
A1 - Kadow, Stephanie
A1 - Schumacher, Fabian
A1 - Mohamed, Zainelabdeen H.
A1 - Kappe, Christian
A1 - Hessler, Gabriele
A1 - Pollmeier, Barbara
A1 - Kleuser, Burkhard
A1 - Arenz, Christoph
A1 - Becker, Katrin Anne
A1 - Gulbins, Erich
A1 - Carpinteiro, Alexander
T1 - Characterization of the small molecule ARC39
BT - a direct and specific inhibitor of acid sphingomyelinase in vitro[S]
JF - Journal of Lipid Research
N2 - Inhibition of acid sphingomyelinase (ASM), a lysosomal enzyme that catalyzes the hydrolysis of sphingomyelin into ceramide and phosphorylcholine, may serve as an investigational tool or a therapeutic intervention to control many diseases. Specific ASM inhibitors are currently not sufficiently characterized. Here, we found that 1-aminodecylidene bis-phosphonic acid (ARC39) specifically and efficiently (>90%) inhibits both lysosomal and secretory ASM in vitro. Results from investigating sphingomyelin phosphodiesterase 1 (SMPD1/Smpd1) mRNA and ASM protein levels suggested that ARC39 directly inhibits ASM's catalytic activity in cultured cells, a mechanism that differs from that of functional inhibitors of ASM. We further provide evidence that ARC39 dose- and time-dependently inhibits lysosomal ASM in intact cells, and we show that ARC39 also reduces platelet- and ASM-promoted adhesion of tumor cells. The observed toxicity of ARC39 is low at concentrations relevant for ASM inhibition in vitro, and it does not strongly alter the lysosomal compartment or induce phospholipidosis in vitro. When applied intraperitoneally in vivo, even subtoxic high doses administered short-term induced sphingomyelin accumulation only locally in the peritoneal lavage without significant accumulation in plasma, liver, spleen, or brain. These findings require further investigation with other possible chemical modifications. In conclusion, our results indicate that ARC39 potently and selectively inhibits ASM in vitro and highlight the need for developing compounds that can reach tissue concentrations sufficient for ASM inhibition in vivo.
KW - sphingolipids
KW - sphingomyelin
KW - cerami-des
KW - lipid metabolism
KW - enzymology
KW - lysosome
KW - lysosomal hydrolases
KW - acid ceramidase
KW - bisphosphonates
KW - functional inhibitors of acid sphin-gomyelinase
KW - 1-aminodecylidene bis-phosphonic acid
Y1 - 2021
U6 - https://doi.org/10.1194/jlr.RA120000682
SN - 1539-7262
SN - 0022-2275
VL - 61
IS - 6
SP - 896
EP - 910
PB - American Society for Biochemistry and Molecular Biology
CY - Bethesda
ER -
TY - JOUR
A1 - Puppe, Daniel
A1 - Kaczorek, Danuta
A1 - Schaller, Jörg
A1 - Barkusky, Dietmar
A1 - Sommer, Michael
T1 - Crop straw recycling prevents anthropogenic desilication of agricultural soil-plant systems in the temperate zone
BT - results from a long-term field experiment in NE Germany
JF - Geoderma : an international journal of soil science
N2 - Due to the fact that silicon (Si) increases the resistance of plants against diverse abiotic and biotic stresses, Si nowadays is categorized as beneficial substance for plants. However, humans directly influence Si cycling on a global scale. Intensified agriculture and corresponding harvest-related Si exports lead to Si losses in agricultural soils. This anthropogenic desilication might be a big challenge for modern agriculture. However, there is still only little knowledge about Si cycling in agricultural systems of the temperate zone, because most studies focus on rice and sugarcane production in (sub)tropical areas. Furthermore, many studies are performed for a short term only, and thus do not provide the opportunity to analyze slow changes in soil-plant systems (e.g., desilication) over long periods. We analyzed soil and plant samples from an ongoing long-term field experiment (established 1963) in the temperate zone (NE Germany) to evaluate the effects of different nitrogen-phosphoruspotassium (NPK) fertilization rates and crop straw recycling (i.e., straw incorporation) on anthropogenic desilication in the long term. Our results clearly show that crop straw recycling not only prevents anthropogenic desilication (about 43-60% of Si exports can be saved by crop straw recycling in the long term), but also replenishes plant available Si stocks of agricultural soil-plant systems. Furthermore, we found that a reduction of N fertilization rates of about 69% is possible without considerable biomass losses. This economy of the need for N fertilizers potentially can be combined with the benefits of crop straw recycling, i.e., enhancement of carbon sequestration via straw inputs and prevention of anthropogenic desilication of agricultural soil-plant systems. Thus crop straw recycling might have the potential to act as key management practice in sustainable, low fertilization agriculture in the temperate zone in the future.
KW - Sustainable crop production
KW - Straw incorporation
KW - Phytoliths
KW - Silicon exports
KW - Plant available Si
Y1 - 2021
U6 - https://doi.org/10.1016/j.geoderma.2021.115187
SN - 0016-7061
SN - 1872-6259
VL - 403
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Stamenov, Yavor
T1 - Beweislast für Schadensersatzansprüche nach Art. EWG_DSGVO Artikel 82 DS-GVO
BT - Art. 5 II, 15, 24 I, 82 DS-GVO; § 174 BGB
JF - Recht Digital
Y1 - 2021
UR - https://beck-online.beck.de/Bcid/Y-300-Z-RDI-B-2021-S-410-N-1
SN - 2702-2404
VL - 2
IS - 8
SP - 410
EP - 413
PB - C.H. Beck
CY - München
ER -
TY - JOUR
A1 - große Deters, Fenne
A1 - Meier, Tabea
A1 - Milek, Anne
A1 - Horn, Andrea B.
T1 - Self-focused and other-focused health concerns as predictors of the uptake of corona contact tracing apps
BT - Empirical Study
JF - Journal of medical internet research
N2 - Background:
Corona contact tracing apps are a novel and promising measure to reduce the spread of COVID-19. They can help to balance the need to maintain normal life and economic activities as much as possible while still avoiding exponentially growing case numbers. However, a majority of citizens need to be willing to install such an app for it to be effective. Hence, knowledge about drivers for app uptake is crucial.
Objective:
This study aimed to add to our understanding of underlying psychological factors motivating app uptake. More specifically, we investigated the role of concern for one's own health and concern to unknowingly infect others.
Methods:
A two-wave survey with 346 German-speaking participants from Switzerland and Germany was conducted. We measured the uptake of two decentralized contact tracing apps officially launched by governments (Corona-Warn-App, Germany; SwissCovid, Switzerland), as well as concerns regarding COVID-19 and control variables.
Results:
Controlling for demographic variables and general attitudes toward the government and the pandemic, logistic regression analysis showed a significant effect of self-focused concerns (odds ratio [OR] 1.64, P=.002). Meanwhile, concern of unknowingly infecting others did not contribute significantly to the prediction of app uptake over and above concern for one's own health (OR 1.01, P=.92). Longitudinal analyses replicated this pattern and showed no support for the possibility that app uptake provokes changes in levels of concern. Testing for a curvilinear relationship, there was no evidence that "too much" concern leads to defensive reactions and reduces app uptake.
Conclusions:
As one of the first studies to assess the installation of already launched corona tracing apps, this study extends our knowledge of the motivational landscape of app uptake. Based on this, practical implications for communication strategies and app design are discussed.
KW - COVID-19
KW - corona contact tracing app
KW - digital proximity tracing
KW - preventive behavior
KW - health concern
KW - prosocial motivation
KW - public health
KW - risk perception
KW - eHealth
KW - Corona-Warn-App
KW - SwissCovid
KW - contact tracing app
KW - contact tracing
Y1 - 2021
U6 - https://doi.org/10.2196/29268
SN - 1438-8871
VL - 23
IS - 8
PB - Centre of Global eHealth Innovation
CY - Toronto
ER -
TY - JOUR
A1 - Kaech, Heidi
A1 - Dennis, Alice B.
A1 - Vorburger, Christoph
T1 - Triple RNA-Seq characterizes aphid gene expression in response to infection with unequally virulent strains of the endosymbiont Hamiltonella defensa
JF - BMC genomics
N2 - Background
Secondary endosymbionts of aphids provide benefits to their hosts, but also impose costs such as reduced lifespan and reproductive output. The aphid Aphis fabae is host to different strains of the secondary endosymbiont Hamiltonella defensa, which encode different putative toxins. These strains have very different phenotypes: They reach different densities in the host, and the costs and benefits (protection against parasitoid wasps) they confer to the host vary strongly.
Results
We used RNA-Seq to generate hypotheses on why four of these strains inflict such different costs to A. fabae. We found different H. defensa strains to cause strain-specific changes in aphid gene expression, but little effect of H. defensa on gene expression of the primary endosymbiont, Buchnera aphidicola. The highly costly and over-replicating H. defensa strain H85 was associated with strongly reduced aphid expression of hemocytin, a marker of hemocytes in Drosophila. The closely related strain H15 was associated with downregulation of ubiquitin-related modifier 1, which is related to nutrient-sensing and oxidative stress in other organisms. Strain H402 was associated with strong differential regulation of a set of hypothetical proteins, the majority of which were only differentially regulated in presence of H402.
Conclusions
Overall, our results suggest that costs of different strains of H. defensa are likely caused by different mechanisms, and that these costs are imposed by interacting with the host rather than the host's obligatory endosymbiont B. aphidicola.
KW - Aphis fabae
KW - Buchnera
KW - Cost of resistance
KW - Hamiltonella
KW - Host-symbiont interaction
KW - RNA-Seq
KW - Symbiosis
Y1 - 2021
U6 - https://doi.org/10.1186/s12864-021-07742-8
SN - 1471-2164
VL - 22
IS - 1
PB - BioMed Central
CY - London
ER -
TY - JOUR
A1 - Hethey, Christoph Philipp
A1 - Hartung, Niklas
A1 - Wangorsch, Gaby
A1 - Weisser, Karin
A1 - Huisinga, Wilhelm
T1 - Physiology-based toxicokinetic modelling of aluminium in rat and man
JF - Archives of toxicology : official journal of EUROTOX
N2 - A sufficient quantitative understanding of aluminium (Al) toxicokinetics (TK) in man is still lacking, although highly desirable for risk assessment of Al exposure. Baseline exposure and the risk of contamination severely limit the feasibility of TK studies administering the naturally occurring isotope Al-27, both in animals and man. These limitations are absent in studies with Al-26 as a tracer, but tissue data are limited to animal studies. A TK model capable of inter-species translation to make valid predictions of Al levels in humans-especially in toxicological relevant tissues like bone and brain-is urgently needed. Here, we present: (i) a curated dataset which comprises all eligible studies with single doses of Al-26 tracer administered as citrate or chloride salts orally and/or intravenously to rats and humans, including ultra-long-term kinetic profiles for plasma, blood, liver, spleen, muscle, bone, brain, kidney, and urine up to 150 weeks; and (ii) the development of a physiology-based (PB) model for Al TK after intravenous and oral administration of aqueous Al citrate and Al chloride solutions in rats and humans. Based on the comprehensive curated Al-26 dataset, we estimated substance-dependent parameters within a non-linear mixed-effect modelling context. The model fitted the heterogeneous Al-26 data very well and was successfully validated against datasets in rats and humans. The presented PBTK model for Al, based on the most extensive and diverse dataset of Al exposure to date, constitutes a major advancement in the field, thereby paving the way towards a more quantitative risk assessment in humans.
KW - PBTK
KW - Toxicokinetics
KW - Al-26
KW - Aluminium
Y1 - 2021
U6 - https://doi.org/10.1007/s00204-021-03107-y
SN - 0340-5761
SN - 1432-0738
VL - 95
IS - 9
SP - 2977
EP - 3000
PB - Springer
CY - Berlin ; Heidelberg
ER -
TY - JOUR
A1 - Raman Venkatesan, Thulasinath
A1 - Smykalla, David
A1 - Ploss, Bernd
A1 - Wübbenhorst, Michael
A1 - Gerhard, Reimund
T1 - Non-linear dielectric spectroscopy for detecting and evaluating structure-property relations in a P(VDF-TrFE-CFE) relaxor-ferroelectric terpolymer
JF - Applied physics : A, Materials science & processing
N2 - Non-linear dielectric spectroscopy (NLDS) is employed as an effective tool to study relaxation processes and phase transitions of a poly(vinylidenefluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)) relaxor-ferroelectric (R-F) terpolymer in detail. Measurements of the non-linear dielectric permittivity epsilon 2 ' reveal peaks at 30 and 80 degrees C that cannot be identified in conventional dielectric spectroscopy. By combining the results from NLDS experiments with those from other techniques such as thermally stimulated depolarization and dielectric-hysteresis studies, it is possible to explain the processes behind the additional peaks. The former peak, which is associated with the mid-temperature transition, is found in all other vinylidene fluoride-based polymers and may help to understand the non-zero epsilon 2 ' values that are detected on the paraelectric phase of the terpolymer. The latter peak can also be observed during cooling of P(VDF-TrFE) copolymer samples at 100 degrees C and is due to conduction and space-charge polarization as a result of the accumulation of real charges at the electrode-sample interface.
KW - Non-linear dielectric spectroscopy
KW - P(VDF-TrFE-CFE)
KW - Relaxor-ferroelectric polymer
KW - Dielectric hysteresis
KW - Curie-transition
KW - Mid-temperature transition
Y1 - 2021
U6 - https://doi.org/10.1007/s00339-021-04876-0
SN - 0947-8396
SN - 1432-0630
VL - 127
IS - 10
PB - Springer
CY - Berlin ; Heidelberg ; New York
ER -
TY - JOUR
A1 - Kreuzer, Lucas
A1 - Lindenmeir, Christoph
A1 - Geiger, Christina
A1 - Widmann, Tobias
A1 - Hildebrand, Viet
A1 - Laschewsky, André
A1 - Papadakis, Christine M.
A1 - Müller-Buschbaum, Peter
T1 - Poly(sulfobetaine) versus poly(N-isopropylmethacrylamide)
BT - co-nonsolvency-type behavior of thin films in a water/methanol atmosphere
JF - Macromolecules : a publication of the American Chemical Society
N2 - The swelling and co-nonsolvency behaviors in pure H2O and in a mixed H2O/CH3OH vapor atmosphere of two different polar, water-soluble polymers in thin film geometry are studied in situ. Films of a zwitterionic poly(sulfobetaine), namely, poly[3-((2-(methacryloyloxy)ethyl)dimethylammonio) propane-1-sulfonate] (PSPE), and a polar nonionic polymer, namely, poly(N-isopropylmethacrylamide) (PNIPMAM), are investigated in real time by spectral reflectance (SR) measurements and Fourier transform infrared (FTIR) spectroscopy. Whereas PSPE is insoluble in methanol, PNIPMAM is soluble but exhibits cononsolvency behavior in water/methanol mixtures. First, the swelling of PSPE and PNIPMAM thin films in H2O vapor is followed. Subsequently, CH3OH is added to the vapor atmosphere, and its contracting effect on the water-swollen films is monitored, revealing a co-nonsolvency-type behavior for PNIPMAM and PSPE. SR measurements indicate that PSPE and PNIPMAM behave significantly different during the H2O swelling and subsequent exposure to CH3OH, not only with respect to the amounts of absorbed water and CH3OH, but also to the cosolvent-induced contraction mechanisms. While PSPE thin films exhibit an abrupt one-step contraction, the contraction of PNIPMAM thin films occurs in two steps. FTIR studies corroborate these findings on a molecular scale and reveal the role of the specific functional groups, both during the swelling and the cosolvent-induced switching of the solvation state.
Y1 - 2021
U6 - https://doi.org/10.1021/acs.macromol.0c02281
SN - 0024-9297
SN - 1520-5835
VL - 54
IS - 3
SP - 1548
EP - 1556
PB - American Chemical Society
CY - Washington
ER -
TY - JOUR
A1 - Tokmoldin, Nurlan
A1 - Vollbrecht, Joachim
A1 - Hosseini, Seyed Mehrdad
A1 - Sun, Bowen
A1 - Perdigón-Toro, Lorena
A1 - Woo, Han Young
A1 - Zou, Yingping
A1 - Neher, Dieter
A1 - Shoaee, Safa
T1 - Explaining the fill-factor and photocurrent losses of nonfullerene acceptor-based solar cells by probing the long-range charge carrier diffusion and drift lengths
JF - Advanced energy materials
N2 - Organic solar cells (OSC) nowadays match their inorganic competitors in terms of current production but lag behind with regards to their open-circuit voltage loss and fill-factor, with state-of-the-art OSCs rarely displaying fill-factor of 80% and above. The fill-factor of transport-limited solar cells, including organic photovoltaic devices, is affected by material and device-specific parameters, whose combination is represented in terms of the established figures of merit, such as theta and alpha. Herein, it is demonstrated that these figures of merit are closely related to the long-range carrier drift and diffusion lengths. Further, a simple approach is presented to devise these characteristic lengths using steady-state photoconductance measurements. This yields a straightforward way of determining theta and alpha in complete cells and under operating conditions. This approach is applied to a variety of photovoltaic devices-including the high efficiency nonfullerene acceptor blends-and show that the diffusion length of the free carriers provides a good correlation with the fill-factor. It is, finally, concluded that most state-of-the-art organic solar cells exhibit a sufficiently large drift length to guarantee efficient charge extraction at short circuit, but that they still suffer from too small diffusion lengths of photogenerated carriers limiting their fill factor.
KW - diffusion length
KW - drift length
KW - figure of merit
KW - lifetime‐ mobility product
KW - steady‐ state photoconductance
Y1 - 2021
U6 - https://doi.org/10.1002/aenm.202100804
SN - 1614-6840
VL - 11
IS - 22
PB - Wiley-VCH
CY - Weinheim
ER -
TY - JOUR
A1 - Schlemm, Tanja
A1 - Levermann, Anders
T1 - A simple parametrization of mélange buttressing for calving glaciers
JF - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2 - Both ice sheets in Greenland and Antarctica are discharging ice into the ocean. In many regions along the coast of the ice sheets, the icebergs calve into a bay. If the addition of icebergs through calving is faster than their transport out of the embayment, the icebergs will be frozen into a melange with surrounding sea ice in winter. In this case, the buttressing effect of the ice melange can be considerably stronger than any buttressing by mere sea ice would be. This in turn stabilizes the glacier terminus and leads to a reduction in calving rates. Here we propose a simple parametrization of ice melange buttressing which leads to an upper bound on calving rates and can be used in numerical and analytical modelling.
Y1 - 2021
U6 - https://doi.org/10.5194/tc-15-531-2021
SN - 1994-0416
SN - 1994-0424
VL - 15
IS - 2
SP - 531
EP - 545
PB - Copernicus
CY - Göttingen
ER -
TY - JOUR
A1 - Eibl, Eva P. S.
A1 - Müller, Daniel
A1 - Walter, Thomas R.
A1 - Allahbakhshi, Masoud
A1 - Jousset, Philippe
A1 - Hersir, Gylfi Páll
A1 - Dahm, Torsten
T1 - Eruptive cycle and bubble trap of Strokkur Geyser, Iceland
JF - Journal of geophysical research : JGR. B: Solid earth
N2 - The eruption frequency of geysers can be studied easily on the surface. However, details of the internal structure including possible water and gas filled chambers feeding eruptions and the driving mechanisms often remain elusive. We used a multidisciplinary network of seismometers, video cameras, water pressure sensors and one tiltmeter to study the eruptive cycle, internal structure, and mechanisms driving the eruptive cycle of Strokkur geyser in June 2018. An eruptive cycle at Strokkur always consists of four phases: (1) Eruption, (2) post-eruptive conduit refilling, (3) gas filling of the bubble trap, and (4) regular bubble collapse at shallow depth in the conduit. For a typical single eruption 19 +/- 4 bubble collapses occur in Phase 3 and 8 +/- 2 collapses in Phase 4 at a mean spacing of 1.52 +/- 0.29 and 24.5 +/- 5.9 s, respectively. These collapses release latent heat to the fluid in the bubble trap (Phase 3) and later to the fluid in the conduit (Phase 4). The latter eventually reaches thermodynamic conditions for an eruption. Single to sextuple eruptions have similar spacings between bubble collapses and are likely fed from the same bubble trap at 23.7 +/- 4.4 m depth, 13-23 m west of the conduit. However, the duration of the eruption and recharging phase linearly increases likely due to a larger water, gas and heat loss from the system. Our tremor data provides documented evidence for a bubble trap beneath a pool geyser.
KW - bubble trap
KW - eruptive cycle
KW - geyser
KW - hydrothermal systems
KW - source
KW - location
KW - tremor
Y1 - 2021
U6 - https://doi.org/10.1029/2020JB020769
SN - 2169-9313
SN - 2169-9356
VL - 126
IS - 4
PB - Wiley
CY - Hoboken, NJ
ER -
TY - JOUR
A1 - Korniienko, Yevheniia
A1 - Nguyen, Linh
A1 - Baumgartner, Stephanie
A1 - Vater, Marianne
A1 - Tiedemann, Ralph
A1 - Kirschbaum, Frank
T1 - Correction to: Intragenus F1-hybrids of African weakly electric fish (Mormyridae: Campylomormyrus tamandua male x C. compressirostris female) are fertile (vol 206, pg 571, 2020)
JF - Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology
Y1 - 2021
U6 - https://doi.org/10.1007/s00359-021-01513-2
SN - 0340-7594
SN - 1432-1351
VL - 207
IS - 6
SP - 773
EP - 773
PB - Springer
CY - Heidelberg
ER -
TY - JOUR
A1 - Spatola, Nicolas
A1 - Kühnlenz, Barbara
A1 - Cheng, Gordon
T1 - Perception and evaluation in human-robot interaction
BT - The Human-Robot Interaction Evaluation Scale (HRIES) - a multicomponent approach of anthropomorphism
JF - International Journal of Social Robotics
N2 - The evaluation of how (human) individuals perceive robots is a central issue to better understand human-robot interaction (HRI). On this topic, promising proposals have emerged. However, present tools are not able to assess a sufficient part of the composite psychological dimensions involved in the evaluation of HRI. Indeed, the percentage of variance explained is often under the recommended threshold for a construct to be valid. In this article, we consolidate the lessons learned from three different studies and propose a further developed questionnaire based on a multicomponent approach of anthropomorphism by adding traits from psychosocial theory about the perception of others and the attribution and deprivation of human characteristics: the de-humanization theory. Among these characteristics, the attribution of agency is of main interest in the field of social robotics as it has been argued that robots could be considered as intentional agents. Factor analyses reveal a four sub-dimensions scale including Sociability, Agency, Animacy, and the Disturbance. We discuss the implication(s) of these dimensions on future perception of and attitudes towards robots.
KW - Robot perception
KW - Robot evaluation
KW - Anthropomorphism
KW - Scale
KW - Questionnaire
KW - Human-robot interaction
Y1 - 2021
U6 - https://doi.org/10.1007/s12369-020-00667-4
SN - 1875-4791
SN - 1875-4805
VL - 13
IS - 7
SP - 1517
EP - 1539
PB - Springer
CY - Dordrecht
ER -
TY - JOUR
A1 - Jafarnezhadgero, AmirAli
A1 - Ghorbanloo, Farshad
A1 - Fatollahi, Amir
A1 - Dionisio, Valdeci Carlos
A1 - Granacher, Urs
T1 - Effects of an elastic resistance band exercise program on kinetics and muscle activities during walking in young adults with genu valgus
BT - A double-blinded randomized controlled trial
JF - Clinical biomechanics : a journal affiliated to the International Society of Biomechanics and the American Society of Biomechanics
N2 - Background:
This double-blinded randomized-controlled-trial aimed to identify the effects of an elastic band resistance training on walking kinetics and muscle activities in young adults with genu valgus.
Methods:
Forty-two male young adults aged 22.5(2.7) years with genu valgus were randomly allocated to two experimental groups. The intervention group (n = 21) conducted a 14-weeks elastic band resistance training. The control group was passive during the intervention period and received the same treatment after the post-tests. Pre and post training, ground reaction forces and lower limb muscle activities were recorded during walking.
Findings:
Results revealed significant group-by-time interactions for peak medial ground reaction force and timeto-peak for posterior ground reaction force in favor of the intervention group (p < 0.012; d = 0.83-3.76). Resistance training with elastic bands resulted in significantly larger peak medial ground reaction force (p < 0.001; d = 1.45) and longer time-to-peak for posterior ground reaction force (p < 0.001; d = 1.85). Finding showed significant group-by-time interactions for peak positive free moment amplitudes in favor of the intervention group (p < 0.001; d = 1.18-2.02). Resistance training resulted in a lower peak positive free moment amplitude (p = 0.001; d = 1.46). With regards to muscle activities, the analysis revealed significant group-by time interactions for rectus femoris and gluteus medius activities during the push-off phase in favor of the intervention group (p < 0.038; d = 0.68-0.89). Resistance training induced higher rectus femoris (p = 0.038; d = 0.84) and gluteus medius (p = 0.007; d = 0.54) activities.
Interpretation:
This study proved the effectiveness of resistance training using elastic bands on kinetics and muscle activities during walking in male adults with genu valgus disorder. Given that this training regime is low cost, effective, and easy-to-administer, we suggest that it should be implemented as a rehabilitative or preventive means for young adults with genu valgus.
KW - Free moment
KW - Gait
KW - Knee valgus
KW - Loading rate
KW - Theraband training
Y1 - 2021
U6 - https://doi.org/10.1016/j.clinbiomech.2020.105215
SN - 0268-0033
SN - 1879-1271
VL - 81
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Cherstvy, Andrey G.
A1 - Safdari, Hadiseh
A1 - Metzler, Ralf
T1 - Anomalous diffusion, nonergodicity, and ageing for exponentially and logarithmically time-dependent diffusivity
BT - striking differences for massive versus massless particles
JF - Journal of physics. D, Applied physics
N2 - We investigate a diffusion process with a time-dependent diffusion coefficient, both exponentially increasing and decreasing in time, D(t)=D-0(e +/- 2 alpha t). For this (hypothetical) nonstationary diffusion process we compute-both analytically and from extensive stochastic simulations-the behavior of the ensemble- and time-averaged mean-squared displacements (MSDs) of the particles, both in the over- and underdamped limits. Simple asymptotic relations derived for the short- and long-time behaviors are shown to be in excellent agreement with the results of simulations. The diffusive characteristics in the presence of ageing are also considered, with dramatic differences of the over- versus underdamped regime. Our results for D(t)=D-0(e +/- 2 alpha t) extend and generalize the class of diffusive systems obeying scaled Brownian motion featuring a power-law-like variation of the diffusivity with time, D(t) similar to t(alpha-1). We also examine the logarithmically increasing diffusivity, D(t)=D(0)log[t/tau(0)], as another fundamental functional dependence (in addition to the power-law and exponential) and as an example of diffusivity slowly varying in time. One of the main conclusions is that the behavior of the massive particles is predominantly ergodic, while weak ergodicity breaking is repeatedly found for the time-dependent diffusion of the massless particles at short times. The latter manifests itself in the nonequivalence of the (both nonaged and aged) MSD and the mean time-averaged MSD. The current findings are potentially applicable to a class of physical systems out of thermal equilibrium where a rapid increase or decrease of the particles' diffusivity is inherently realized. One biological system potentially featuring all three types of time-dependent diffusion (power-law-like, exponential, and logarithmic) is water diffusion in the brain tissues, as we thoroughly discuss in the end.
KW - anomalous diffusion
KW - scaled Brownian motion
KW - stochastic processes
KW - nonstationary diffusivity
KW - water diffusion in the brain
KW - nonergodicity
Y1 - 2021
U6 - https://doi.org/10.1088/1361-6463/abdff0
SN - 0022-3727
SN - 1361-6463
VL - 54
IS - 19
PB - IOP Publ. Ltd.
CY - Bristol
ER -
TY - JOUR
A1 - Mioni, Giovanna
A1 - Fischer, Martin H.
A1 - Shaki, Samuel
T1 - Heuristics and biases in the mental manipulation of magnitudes
BT - Evidence from length and time production
JF - Quarterly journal of experimental psychology / published in association with Experimental Psychology Society
N2 - There is a debate about whether and why we overestimate addition and underestimate subtraction results (Operational Momentum or OM effect). Spatial-attentional accounts of OM compete with a model which postulates that OM reflects a weighted combination of multiple arithmetic heuristics and biases (AHAB). This study addressed this debate with the theoretically diagnostic distinction between zero problems (e.g., 3 + 0, 3 - 0) and non-zero problems (e.g., 2 + 1, 4 - 1) because AHAB, in contrast to all other accounts, uniquely predicts reverse OM for the latter problem type. In two tests (line-length production and time production), participants indeed produced shorter lines and under-estimated time intervals in non-zero additions compared with subtractions. This predicted interaction between operation and problem type extends OM to non-spatial magnitudes and highlights the strength of AHAB regarding different problem types and modalities during the mental manipulation of magnitudes. They also suggest that OM reflects methodological details, whereas reverse OM is the more representative behavioural signature of mental arithmetic.
KW - Heuristics and biases
KW - mental arithmetic
KW - operational momentum
KW - SNARC
KW - effect
Y1 - 2021
U6 - https://doi.org/10.1177/1747021820967663
SN - 1747-0218
SN - 1747-0226
VL - 74
IS - 3
SP - 536
EP - 547
PB - SAGE Publishing
CY - Thousand Oaks, CA
ER -
TY - JOUR
A1 - Saretia, Shivam
A1 - Machatschek, Rainhard Gabriel
A1 - Lendlein, Andreas
T1 - Degradation kinetics of oligo(ε-caprolactone) ultrathin films
BT - Influence of crystallinity
JF - MRS advances : a journal of the Materials Research Society (MRS)
N2 - The potential of using crystallinity as morphological parameter to control polyester degradation in acidic environments is explored in ultrathin films by Langmuir technique. Films of hydroxy or methacrylate end-capped oligo(epsilon-caprolactone) (OCL) are prepared at the air-water interface as a function of mean molecular area (MMA). The obtained amorphous, partially crystalline or highly crystalline ultrathin films of OCL are hydrolytically degraded at pH similar to 1.2 on water surface or on silicon surface as-transferred films. A high crystallinity reduces the hydrolytic degradation rate of the films on both water and solid surfaces. Different acceleration rates of hydrolytic degradation of semi-crystalline films are achieved either by crystals complete melting, partially melting, or by heating them below their melting temperatures. Semi-crystalline OCL films transferred via water onto a solid surface retain their crystalline morphology, degrade in a controlled manner, and are of interest as thermoswitchable coatings for cell substrates and medical devices.
Y1 - 2021
U6 - https://doi.org/10.1557/s43580-021-00067-4
SN - 2059-8521
VL - 6
IS - 33
SP - 790
EP - 795
PB - Springer Nature Switzerland AG
CY - Cham
ER -
TY - JOUR
A1 - Ercan, Habibe
A1 - Hartmann, Ulrike
A1 - Richter, Dirk
A1 - Kuschel, Jenny
A1 - Gräsel, Cornelia
T1 - Effekte von integrativer Führung auf die Datennutzung von Lehrkräften
JF - Die deutsche Schule : DDS : Zeitschrift für Erziehungswissenschaft, Bildungspolitik und pädagogische Praxis
N2 - The present article reports the effects of school principals' integrative leadership behavior, including transformational and instructional components, on teachers' data use. Results of a structural equation model indicate significant positive direct and indirect effects on teachers' use of various data. Total effects seem to be mainly mediated by teachers' cooperation activities.
N2 - Die vorliegende Studie untersucht die Zusammenhänge zwischen integrativem Schulleitungshandeln, das transformationale und instruktionale Komponenten enthält, und der Nutzungshäufigkeit verschiedener Datenquellen durch Lehrkräfte. Die Ergebnisse eines Strukturgleichungsmodells zeigen, dass integrative Führung direkte und indirekte Zusammenhänge mit der Nutzung verschiedener Datenquellen aufweist. Die Effekte scheinen vorwiegend durch die Kooperationsaktivität der Lehrkräfte vermittelt zu sein.
T2 - Data-based school improvement - direct and indirect effects of integrative leadership on teachers' data use
KW - teachers' data use
KW - integrative leadership
KW - cooperation
KW - Datennutzung von Lehrkräften
KW - integrative Führung
KW - Kooperation
Y1 - 2021
U6 - https://doi.org/10.31244/dds.2021.01.08
SN - 0012-0731
SN - 2699-5379
VL - 113
IS - 1
SP - 85
EP - 100
PB - Waxmann
CY - Münster
ER -
TY - JOUR
A1 - Schoeps, Julius H.
T1 - Theodor Lessing, der „Prager Kreis“ und sein weiteres Umfeld
JF - Zeitschrift für Religions- und Geistesgeschichte
JF - Journal of religious and cultural studies
N2 - Theodor Lessing was a German-Jewish philosopher, Zionist, Communist and member of the Prager Kreis. He wrote psychological studies of Judaism and influenced with his main philosophical works Geschichte als Sinngebung des Sinnlosen (1919) and Europa und Asien (1918, and 1924) the German speaking scholars and contemporaries in Germany and elsewhere. He was killed by the Nazis in 1933 as one of the first victims of National Socialism.
T2 - Theodor Lessing, the "Prague Circle" and its wider environment
Y1 - 2021
U6 - https://doi.org/10.1163/15700739-07302005
SN - 0044-3441
SN - 1570-0739
VL - 73
IS - 2
SP - 121
EP - 140
PB - Brill
CY - Leiden
ER -
TY - JOUR
A1 - Schlomann, Anna
A1 - Bünning, Mareike
A1 - Hipp, Lena
A1 - Wahl, Hans-Werner
T1 - Aging during COVID-19 in Germany
BT - a longitudinal analysis of psychosocial adaptation
JF - European journal of ageing : social, behavioural and health perspectives
N2 - Existing theories of aging suggest that there may be similarities and differences in how COVID-19 impacts older people’s psychosocial adaptation compared to younger age groups, particularly middle-aged individuals. To assess the degree to which these impacts vary, we analyzed data from 3098 participants between the ages of 40 and 79 from an online survey in Germany. Data were collected at three measurement occasions between the start of the nationwide lockdown in mid-March 2020 and the end of the lockdown in early August 2020. The survey focused on everyday experiences during the COVID-19 crisis and collected various satisfaction ratings (e.g., general life satisfaction, satisfaction with family life, satisfaction with social contacts). At baseline, participants also provided retrospective ratings of satisfaction for the period before the COVID-19 crisis. In our analyses, we compared satisfaction ratings of middle-aged (40–64 years) and older individuals (65–79 years) and found that both middle-aged and older participants experienced the greatest decreases in satisfaction with social contacts, with more pronounced decreases seen in middle-aged participants. A similar pattern was observed for general life satisfaction, but the overall decreases were less pronounced in both groups compared to the decreases in satisfaction with social contacts. We also observed a partial recovery effect in all measures at the last measurement occasion, and this effect was more pronounced in older adults. Findings were also confirmed using age as a continuous variable and checking for linear and nonlinear effects of outcomes across the age range. Although ageism arose during the pandemic in the sense that older adults were labeled as a “risk group,” particularly at the start of the outbreak, we found consistently with other studies that middle-aged adults’ satisfaction decreased to a greater extent than that of older adults.
KW - Coronavirus pandemic
KW - older adults
KW - satisfaction with life
KW - satisfaction with social relations
KW - age stereotypes
KW - longitudinal survey study
Y1 - 2021
U6 - https://doi.org/10.1007/s10433-021-00655-1
SN - 1613-9372
SN - 1613-9380
VL - 19
IS - 4
SP - 1077
EP - 1086
PB - Springer
CY - Berlin
ER -
TY - JOUR
A1 - Bünning, Mareike
A1 - Hipp, Lena
T1 - Geschlechterungleichheiten im Arbeitsleben und subjektiven Wohlbefinden von Erwerbstätigen während der COVID-19-Pandemie
T1 - Gender Inequalities in Employment and Subjective-Wellbeing among the Employed during the COVID-19 Pandemic
JF - Sozialer Fortschritt
N2 - Wie hat sich die COVID-19 Pandemie auf geschlechtsspezifische Ungleichheiten im Arbeitsleben und dem subjektiven Wohlbefinden Erwerbstätiger ausgewirkt? Zur Beantwortung dieser Frage analysiert dieser Beitrag drei Wellen einer nicht zufallsbasierten Onlinestichprobe für den Zeitraum Mitte März bis Anfang August 2020 und umfassen damit den Zeitraum des ersten Lockdowns. Die Ergebnisse unserer multivariaten Analysen zeigen: Frauen, Eltern und insbesondere Mütter waren überdurchschnittlich von Arbeitszeitreduzierungen betroffen. Bei der Wahrscheinlichkeit im Homeoffice zu arbeiten gab es nur geringfügige Unterschiede nach Geschlecht und Familiensituation. Die Zufriedenheit mit der Arbeit, dem Familienleben und dem Leben insgesamt ging bei Frauen, Eltern und insbesondere Müttern überproportional stark zurück. Die beobachteten Unterschiede verringern sich gegen Ende des Lockdowns wieder, jedoch unterschiedlich stark für die einzelnen Ergebnisdimensionen.
N2 - How has the COVID-19 pandemic affected gender inequalities in employment and the subjective well-being of the employed? To answer this question, we analyze three waves of a non-randomized online-survey from mid-March to the beginning of August 2020. The results of our multivariate analyses show: Women, parents, and especially mothers were disproportionately affected by working-time reductions. The likelihood of working from home differed only marginally by gender and family situation. Declines in satisfaction with work, family life and life in general were stronger among women, parents, and especially mothers. The observed differences decreased towards the end of the lockdown-phase, though to different extends for different outcomes.
Y1 - 2021
U6 - https://doi.org/10.3790/sfo.70.5-6.293
SN - 0038-609X
SN - 1865-5386
VL - 70
IS - 5-6
SP - 293
EP - 315
PB - Duncker & Humblot
CY - Berlin
ER -
TY - JOUR
A1 - Klemme, Stephan
A1 - Feldhaus, Michael
A1 - Potapkin, Vasily
A1 - Wilke, Max
A1 - Borchert, Manuela
A1 - Louvel, Marion
A1 - Loges, Anselm
A1 - Rohrbach, Arno
A1 - Weitkamp, Petra
A1 - Welter, Edmund
A1 - Kokh, Maria A.
A1 - Schmidt, Christian
A1 - Testemale, Denis
T1 - A hydrothermal apparatus for x-ray absorption spectroscopy of hydrothermal fluids at DESY
JF - Review of scientific instruments : a monthly journal devoted to scientific instruments, apparatus, and techniques
N2 - We present a new autoclave that enables in situ characterization of hydrothermal fluids at high pressures and high temperatures at synchrotron x-ray radiation sources. The autoclave has been specifically designed to enable x-ray absorption spectroscopy in fluids with applications to mineral solubility and element speciation analysis in hydrothermal fluids in complex compositions. However, other applications, such as Raman spectroscopy, in high-pressure fluids are also possible with the autoclave. First experiments were run at pressures between 100 and 600 bars and at temperatures between 25 degrees C and 550 degrees C, and preliminary results on scheelite dissolution in fluids of different compositions show that the autoclave is well suited to study the behavior of ore-forming metals at P-T conditions relevant to the Earth's crust.
Y1 - 2021
U6 - https://doi.org/10.1063/5.0044767
SN - 0034-6748
SN - 1089-7623
VL - 92
IS - 6
PB - AIP Publishing
CY - Melville
ER -
TY - JOUR
A1 - Letellier, Christophe
A1 - Abraham, Ralph
A1 - Shepelyansky, Dima L.
A1 - Rossler, Otto E.
A1 - Holmes, Philip
A1 - Lozi, Rene
A1 - Glass, Leon
A1 - Pikovsky, Arkady
A1 - Olsen, Lars F.
A1 - Tsuda, Ichiro
A1 - Grebogi, Celso
A1 - Parlitz, Ulrich
A1 - Gilmore, Robert
A1 - Pecora, Louis M.
A1 - Carroll, Thomas L.
T1 - Some elements for a history of the dynamical systems theory
JF - Chaos : an interdisciplinary journal of nonlinear science
N2 - Writing a history of a scientific theory is always difficult because it requires to focus on some key contributors and to "reconstruct" some supposed influences. In the 1970s, a new way of performing science under the name "chaos" emerged, combining the mathematics from the nonlinear dynamical systems theory and numerical simulations. To provide a direct testimony of how contributors can be influenced by other scientists or works, we here collected some writings about the early times of a few contributors to chaos theory. The purpose is to exhibit the diversity in the paths and to bring some elements-which were never published-illustrating the atmosphere of this period. Some peculiarities of chaos theory are also discussed.
Y1 - 2021
U6 - https://doi.org/10.1063/5.0047851
SN - 1054-1500
SN - 1089-7682
VL - 31
IS - 5
PB - AIP Publishing
CY - Melville
ER -
TY - JOUR
A1 - Süsser, Diana
A1 - Gaschnig, Hannes
A1 - Ceglarz, Andrzej
A1 - Stavrakas, Vassilis
A1 - Flamos, Alexandros
A1 - Lilliestam, Johan
T1 - Better suited or just more complex?
BT - on the fit between user needs and modeller-driven improvements of energy system models
JF - Energy
N2 - Energy system models are advancing rapidly. However, it is not clear whether models are becoming better, in the sense that they address the questions that decision-makers need to be answered to make well-informed decisions. Therefore, we investigate the gap between model improvements relevant from the perspective of modellers compared to what users of model results think models should address. Thus, we ask: What are the differences between energy model improvements as perceived by modellers, and the actual needs of users of model results? To answer this question, we conducted a literature review, 32 interviews, and an online survey. Our results show that user needs and ongoing improvements of energy system models align to a large degree so that future models are indeed likely to be better than current models. We also find mismatches between the needs of modellers and users, especially in the modelling of social, behavioural and political aspects, the trade-off between model complexity and understandability, and the ways that model results should be communicated. Our findings suggest that a better understanding of user needs and closer cooperation between modellers and users is imperative to truly improve models and unlock their full potential to support the transition towards climate neutrality in Europe.
KW - energy systems modelling
KW - energy transition
KW - user needs
KW - energy policymaking
KW - climate neutrality
KW - European union
Y1 - 2021
U6 - https://doi.org/10.1016/j.energy.2021.121909
SN - 0360-5442
SN - 1873-6785
VL - 239
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Nedora, Vsevolod
A1 - Radice, David
A1 - Bernuzzi, Sebastiano
A1 - Perego, Albino
A1 - Daszuta, Boris
A1 - Endrizzi, Andrea
A1 - Prakash, Aviral
A1 - Schianchi, Federico
T1 - Dynamical ejecta synchrotron emission as a possible contributor to the changing behaviour of GRB170817A afterglow
JF - Monthly notices of the Royal Astronomical Society
N2 - Over the past 3 yr, the fading non-thermal emission from the GW170817 remained generally consistent with the afterglow powered by synchrotron radiation produced by the interaction of the structured jet with the ambient medium. Recent observations by Hajela et al. indicate the change in temporal and spectral behaviour in the X-ray band. We show that the new observations are compatible with the emergence of a new component due to non-thermal emission from the fast tail of the dynamical ejecta of ab-initio binary neutron star merger simulations. This provides a new avenue to constrain binary parameters. Specifically, we find that equal mass models with soft equations of state (EOSs) and high-mass ratio models with stiff EOSs are disfavoured as they typically predict afterglows that peak too early to explain the recent observations. Moderate stiffness and mass ratio models, instead, tend to be in good overall agreement with the data.
KW - equation of state
KW - gravitational waves
KW - neutron star mergers
Y1 - 2021
U6 - https://doi.org/10.1093/mnras/stab2004
SN - 0035-8711
SN - 1365-2966
VL - 506
IS - 4
SP - 5908
EP - 5915
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Olas, Justyna Jadwiga
A1 - Apelt, Federico
A1 - Watanabe, Mutsumi
A1 - Höfgen, Rainer
A1 - Wahl, Vanessa
T1 - Developmental stage-specific metabolite signatures in Arabidopsis thaliana under optimal and mild nitrogen limitation
JF - Plant science : an international journal of experimental plant biology
N2 - Metabolites influence flowering time, and thus are among the major determinants of yield. Despite the reported role of trehalose 6-phosphate and nitrate signaling on the transition from the vegetative to the reproductive phase, little is known about other metabolites contributing and responding to developmental phase changes. To increase our understanding which metabolic traits change throughout development in Arabidopsis thaliana and to identify metabolic markers for the vegetative and reproductive phases, especially among individual amino acids (AA), we profiled metabolites of plants grown in optimal (ON) and limited nitrogen (N) (LN) conditions, the latter providing a mild but consistent limitation of N. We found that although LN plants adapt their growth to a decreased level of N, their metabolite profiles are strongly distinct from ON plant profiles, with N as the driving factor for the observed differences. We demonstrate that the vegetative and the reproductive phase are not only marked by growth parameters such as biomass and rosette area, but also by specific metabolite signatures including specific single AA. In summary, we identified N-dependent and -independent indicators manifesting developmental stages, indicating that the plant's metabolic status also reports on the developmental phases.
KW - Amino acids
KW - Floral induction
KW - Flowering time
KW - Nitrogen
KW - Metabolites
KW - Vegetative phase
KW - Reproductive phase
Y1 - 2021
U6 - https://doi.org/10.1016/j.plantsci.2020.110746
SN - 0168-9452
SN - 1873-2259
VL - 303
PB - Elsevier Science
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Juang, Linda P.
A1 - Schwarzenthal, Miriam
A1 - Moffitt, Ursula Elinor
A1 - Vietze, Jana
T1 - "No, where are you really from?"
BT - Testing the foreigner objectification scale with German adolescents
BT - Testen der Foreigner Objectification Scale mit deutschen Jugendlichen
JF - Zeitschrift für Entwicklungspsychologie und pädagogische Psychologie : Organ der Fachgruppen Entwicklungspsychologie und Pädagogische Psychologie der Deutschen Gesellschaft für Psychologie (DGPs)
N2 - Being perceived as a foreigner regardless of one's generational status, citizenship, or self-identification is called foreigner objectification. This is a form of identity denial and is linked to psychological distress. To test how foreigner objectification could be measured in Europe, we assessed whether the Foreigner Objectification Scale demonstrated reliability and validity with German adolescents. The sample included 806 9th graders from 17 high schools. The results showed that the scale demonstrates good reliability, scalar measurement invariance across gender and citizenship status, and partial scalar measurement invariance across family heritage, generational status, and cultural self-identification. Adolescents who scored higher on the scale also reported greater school behavioral disengagement, lower life satisfaction, and stronger ethnic identity. Our findings suggest that the scale is psychometrically sound and is linked in theoretically consistent ways to adjustment and ethnic identity. We conclude that this scale offers another way to capture subtle discrimination experiences that add to a more comprehensive understanding of discrimination and the related implications in Europe.
N2 - Als Ausländer_in wahrgenommen zu werden, unabhängig vom Generationsstatus, der Staatsbürgerschaft oder der Selbstidentifikation, wird „foreigner objectification“ (Ausländer_innenobjektifizierung) genannt. Ausländer_innenobjektifizierung ist eine Form der Identitätsverleugnung und wird mit größerem psychologischem Stress in Verbindung gebracht. Um zu testen, wie Ausländer_innenobjektifizierung in Europa gemessen werden kann, untersuchten wir, ob die Foreigner Objectification Scale bei deutschen Jugendlichen Reliabilität und Validität aufweist. Die Stichprobe umfasste 806 Neuntklässler_innen aus 17 Sekundarschulen. Die Ergebnisse zeigten, dass die Skala eine gute Reliabilität, skalare Messinvarianz über das Geschlecht und die Staatsbürgerschaft sowie eine partielle skalare Messinvarianz über die familiäre Herkunft, den Generationsstatus und die kulturelle Selbstidentifikation aufweist. Jugendliche, die höhere Werte auf der Skala erreichten, berichteten auch über ein größeres schulisches Disengagement, eine geringere Lebenszufriedenheit und eine stärkere ethnische Identität. Unsere Ergebnisse deuten darauf hin, dass die Skala psychometrisch solide ist und auf theoretisch konsistente Weise mit Adaptation und ethnischer Identität verbunden ist. Wir kommen zu dem Schluss, dass diese Skala eine weitere Möglichkeit bietet, subtile Diskriminierungserfahrungen zu erfassen, die zu einem umfassenderen Verständnis von Diskriminierung und deren Auswirkungen in Europa beitragen.
T2 - „Nein, woher kommst du denn wirklich?”
KW - discrimination
KW - foreigner objectification
KW - migration
KW - microaggression
KW - Diskriminierung
KW - Ausländer_innenobjektifizierung
KW - Migration
KW - Mikroaggression
Y1 - 2021
U6 - https://doi.org/10.1026/0049-8637/a000242
SN - 0049-8637
SN - 2190-6262
VL - 53
IS - 3-4
SP - 82
EP - 93
PB - Hogrefe
CY - Göttingen
ER -
TY - JOUR
A1 - Boyadzhieva, Asena
A1 - Kayhan, Ezgi
T1 - Keeping the breath in mind
BT - respiration, neural oscillations, and the free energy principle
JF - Frontiers in neuroscience / Frontiers Research Foundation
N2 - Scientific interest in the brain and body interactions has been surging in recent years. One fundamental yet underexplored aspect of brain and body interactions is the link between the respiratory and the nervous systems. In this article, we give an overview of the emerging literature on how respiration modulates neural, cognitive and emotional processes. Moreover, we present a perspective linking respiration to the free-energy principle. We frame volitional modulation of the breath as an active inference mechanism in which sensory evidence is recontextualized to alter interoceptive models. We further propose that respiration-entrained gamma oscillations may reflect the propagation of prediction errors from the sensory level up to cortical regions in order to alter higher level predictions. Accordingly, controlled breathing emerges as an easily accessible tool for emotional, cognitive, and physiological regulation.
KW - interoception
KW - respiration-entrained neural oscillations
KW - controlled
KW - breathing
KW - free-energy principle
KW - self-regulation
Y1 - 2021
U6 - https://doi.org/10.3389/fnins.2021.647579
SN - 1662-453X
VL - 15
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Fink, Julian
A1 - Schumacher, Fabian
A1 - Schlegel, Jan
A1 - Stenzel, Philipp
A1 - Wigger, Dominik
A1 - Sauer, Markus
A1 - Kleuser, Burkhard
A1 - Seibel, Jürgen
T1 - Azidosphinganine enables metabolic labeling and detection of sphingolipid de novo synthesis
JF - Organic & biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry
N2 - Here were report the combination of biocompatible click chemistry of omega-azidosphinganine with fluorescence microscopy and mass spectrometry as a powerful tool to elaborate the sphingolipid metabolism. The azide probe was efficiently synthesized over 13 steps starting from l-serine in an overall yield of 20% and was used for live-cell fluorescence imaging of the endoplasmic reticulum in living cells by bioorthogonal click reaction with a DBCO-labeled fluorophore revealing that the incorporated analogue is mainly localized in the endoplasmic membrane like the endogenous species. A LC-MS(/MS)-based microsomal in vitro assay confirmed that omega-azidosphinganine mimics the natural species enabling the identification and analysis of metabolic breakdown products of sphinganine as a key starting intermediate in the complex sphingolipid biosynthetic pathways. Furthermore, the sphinganine-fluorophore conjugate after click reaction was enzymatically tolerated to form its dihydroceramide and ceramide metabolites. Thus, omega-azidosphinganine represents a useful biofunctional tool for metabolic investigations both by in vivo fluorescence imaging of the sphingolipid subcellular localization in the ER and by in vitro high-resolution mass spectrometry analysis. This should reveal novel insights of the molecular mechanisms sphingolipids and their processing enzymes have e.g. in infection.
Y1 - 2021
U6 - https://doi.org/10.1039/d0ob02592e
SN - 1477-0520
SN - 1477-0539
VL - 19
IS - 10
SP - 2203
EP - 2212
PB - Royal Society of Chemistry
CY - Cambridge
ER -
TY - JOUR
A1 - Wendt, Martin
A1 - Senftleben, Nele
A1 - Gros, Patrick
A1 - Schmitt, Thomas
T1 - Coping with environmental extremes
BT - population ecology and behavioural adaptation of Erebia pronoe, an Alpine butterfly species
JF - Insects : open access journal
N2 - Simple Summary:& nbsp;High alpine meadows are home to numerous endemic butterfly species. A combination of climate change and changes in agricultural practices has led to a severe decline in many species. A seemingly unaffected representative of this habitat is Erebia pronoe. We studied the behaviour, resource use and population structure of this species to explain its resilience and estimate its future survival potential. This species shows pronounced protandry in combination with serial eclosion. Males were significantly more active and mobile and were also caught significantly more often than females, resulting in a pronounced shift in sex ratio in the predicted population structure. The adults use a wide range of nectar plants and establish homeranges in areas of high habitat quality. Thus, Erebia pronoe adults use a wide array of resources combined with a slight specialisation to avoid niche overlap with closely related species. The resulting ecological flexibility seems to be an adaptation to unpredictable environmental conditions, which should be the result of a long-lasting adaptation process. Moreover, the combination of opportunism and modest specialisation should also be a good basis for coping with future changes caused by climate and land-use change.
A mark-recapture study of the nominotypical Erebia pronoe in the Alps was conducted to survey its ecological demands and characteristics. Population structure analysis revealed a combination of protandry (one-week earlier eclosion of males) and serial eclosion. Significant differences between both sexes were found in population density (males: 580/ha & PLUSMN; 37 SE; females: 241/ha & PLUSMN; 66 SE), sex-ratio (2.4) and behaviour (57.7 vs. 11.9% flying). Both sexes used a wide range of nectar plants (Asteraceae, 77.3%; Dipsacaceae, 12.3%; Gentianaceae, 9.7%). The use of nectar plants shows a non-specific spectrum, which, however, completely avoids overlap with the locally co-occurring species Erebia nivalis. Movement patterns show the establishment of homeranges, which significantly limits the migration potential. Due to its broad ecological niche, E. pronoe will probably be able to react plastically to the consequences of climate change. The formation of high population densities, the unconcerned endangerment status, the unspecific resource spectrum and the sedentary character of the species make E. pronoe a potential indicator of the quality and general resource occurrence of alpine rupicolous grasslands.
KW - mark-release-recapture
KW - movement patterns
KW - opportunistic behaviour
KW - partial protandry
KW - population demography
Y1 - 2021
U6 - https://doi.org/10.3390/insects12100896
SN - 2075-4450
VL - 12
IS - 10
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Angeleska, Angela
A1 - Omranian, Sara
A1 - Nikoloski, Zoran
T1 - Coherent network partitions
BT - Characterizations with cographs and prime graphs
JF - Theoretical computer science : the journal of the EATCS
N2 - We continue to study coherent partitions of graphs whereby the vertex set is partitioned into subsets that induce biclique spanned subgraphs. The problem of identifying the minimum number of edges to obtain biclique spanned connected components (CNP), called the coherence number, is NP-hard even on bipartite graphs. Here, we propose a graph transformation geared towards obtaining an O (log n)-approximation algorithm for the CNP on a bipartite graph with n vertices. The transformation is inspired by a new characterization of biclique spanned subgraphs. In addition, we study coherent partitions on prime graphs, and show that finding coherent partitions reduces to the problem of finding coherent partitions in a prime graph. Therefore, these results provide future directions for approximation algorithms for the coherence number of a given graph.
KW - Graph partitions
KW - Network clustering
KW - Cographs
KW - Coherent partition
KW - Prime graphs
Y1 - 2021
U6 - https://doi.org/10.1016/j.tcs.2021.10.002
SN - 0304-3975
VL - 894
SP - 3
EP - 11
PB - Elsevier
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Luderer, Gunnar
A1 - Madeddu, Silvia
A1 - Merfort, Leon
A1 - Ueckerdt, Falko
A1 - Pehl, Michaja
A1 - Pietzcker, Robert C.
A1 - Rottoli, Marianna
A1 - Schreyer, Felix
A1 - Bauer, Nico
A1 - Baumstark, Lavinia
A1 - Bertram, Christoph
A1 - Dirnaichner, Alois
A1 - Humpenöder, Florian
A1 - Levesque, Antoine
A1 - Popp, Alexander
A1 - Rodrigues, Renato
A1 - Strefler, Jessica
A1 - Kriegler, Elmar
T1 - Impact of declining renewable energy costs on electrification in low-emission scenarios
JF - Nature energy
N2 - Cost degression in photovoltaics, wind-power and battery storage has been faster than previously anticipated. In the future, climate policy to limit global warming to 1.5–2 °C will make carbon-based fuels increasingly scarce and expensive. Here we show that further progress in solar- and wind-power technology along with carbon pricing to reach the Paris Climate targets could make electricity cheaper than carbon-based fuels. In combination with demand-side innovation, for instance in e-mobility and heat pumps, this is likely to induce a fundamental transformation of energy systems towards a dominance of electricity-based end uses. In a 1.5 °C scenario with limited availability of bioenergy and carbon dioxide removal, electricity could account for 66% of final energy by mid-century, three times the current levels and substantially higher than in previous climate policy scenarios assessed by the Intergovernmental Panel on Climate Change. The lower production of bioenergy in our high-electrification scenarios markedly reduces energy-related land and water requirements.
KW - climate-change mitigation
KW - energy modelling
KW - renewable energy
Y1 - 2021
U6 - https://doi.org/10.1038/s41560-021-00937-z
SN - 2058-7546
VL - 7
IS - 1
SP - 32
EP - 42
PB - Nature Publishing Group
CY - London
ER -
TY - JOUR
A1 - Obiri-Nyarko, Franklin
A1 - Duah, Anthony A.
A1 - Karikari, Anthony Y.
A1 - Agyekum, William A.
A1 - Manu, Evans
A1 - Tagoe, Ralph
T1 - Assessment of heavy metal contamination in soils at the Kpone landfill site, Ghana
BT - implication for ecological and health risk assessment
JF - Chemosphere : chemistry, biology and toxicology as related to environmental problems
N2 - Concentrations of lead (Pb), zinc (Zn), copper (Cu), mercury (Hg), and arsenic (As) in soils at the Kpone landfill site (Ghana) were determined using Atomic Absorption Spectrophotometry (AAS). Further analyses allowed establishing the degree of heavy metals (HMs) pollution, suitability of the soils for agriculture, sources of the HMs and their ecological and health risks. The site was divided into five zones, A, B, C, D, and E, and in all, seventeen (17) soil samples were collected. Average concentrations of Cu fell within the allowable range for agricultural soils in all the zones while average concentrations of Pb, Zn, Hg, and As exceeded the range in some or all the zones. Concentrations of the HMs generally exceeded their respective background value, with all zones showing very high degree of HMs contamination. The pollution load index (PLI) was 16.48, signifying extreme HMs pollution of the entire site. Multivariate statistical analyses revealed that Cu, Zn, and Pb in the soils originated from the deposited waste materials as well as traffic-related activities (e.g. wear and tear of tyres, brakes, and engines) at the site. Hg also originated from the deposited waste materials as well as cement production and oil and coal combustion activities in the study area, while As derived from industrial discharges and metal smelting activities. All the zones exhibited very high ecological risk. The carcinogenic and non-carcinogenic health risks posed by the HMs were also above acceptable levels, with children being more vulnerable than adults to these health risks.
KW - Landfill
KW - Heavy metals
KW - Soil contamination
KW - Geochemical indices
KW - Multivariate statistical analysis
KW - Risk assessment
Y1 - 2021
U6 - https://doi.org/10.1016/j.chemosphere.2021.131007
SN - 0045-6535
SN - 1879-1298
VL - 282
PB - Elsevier
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Folikumah, Makafui Y.
A1 - Behl, Marc
A1 - Lendlein, Andreas
T1 - Reaction behaviour of peptide-based single thiol-thioesters exchange reaction substrate in the presence of externally added thiols
JF - MRS communications / a publication of the Materials Research Society
N2 - Identification of patterns in chemical reaction pathways aids in the effective design of molecules for specific applications. Here, we report on model reactions with a water-soluble single thiol-thioester exchange (TTE) reaction substrate, which was designed taking in view biological and medical applications. This substrate consists of the thio-depsipeptide, Ac-Pro-Leu-Gly-SLeu-Leu-Gly-NEtSH (TDP) and does not yield foul-smelling thiol exchange products when compared with aromatic thiol containing single TTE substrates. TDP generates an alpha,omega-dithiol crosslinker in situ in a 'pseudo intramolecular' TTE. Competitive intermolecular TTE of TDP with externally added "basic" thiols increased the crosslinker concentration whilst "acidic" thiols decreased its concentration. TDP could potentially enable in situ bioconjugation and crosslinking applications.
KW - Biomaterials
KW - Biomimetic
KW - Mass spectrometry
KW - Nuclear magnetic resonance
KW - (NMR)
Y1 - 2021
U6 - https://doi.org/10.1557/s43579-021-00041-z
SN - 2159-6859
SN - 2159-6867
VL - 11
IS - 4
SP - 402
EP - 410
PB - Springer
CY - Berlin
ER -
TY - JOUR
A1 - Ullrich, Sophie Louise
A1 - Hegnauer, Mark
A1 - Nguyen, Dung Viet
A1 - Merz, Bruno
A1 - Kwadijk, Jaap
A1 - Vorogushyn, Sergiy
T1 - Comparative evaluation of two types of stochastic weather generators for synthetic precipitation in the Rhine basin
JF - Journal of hydrology
N2 - Stochastic modeling of precipitation for estimation of hydrological extremes is an important element of flood risk assessment and management. The spatially consistent estimation of rainfall fields and their temporal variability remains challenging and is addressed by various stochastic weather generators.
In this study, two types of weather generators are evaluated against observed data and benchmarked regarding their ability to simulate spatio-temporal precipitation fields in the Rhine catchment. A multi-site station-based weather generator uses an auto-regressive model and estimates the spatial correlation structure between stations. Another weather generator is raster-based and uses the nearest-neighbor resampling technique for reshuffling daily patterns while preserving the correlation structure between the observations.
Both weather generators perform well and are comparable at the point (station) scale with regards to daily mean and 99.9th percentile precipitation as well as concerning wet/dry frequencies and transition probabilities. The areal extreme precipitation at the sub-basin scale is however overestimated in the station-based weather generator due to an overestimation of the correlation structure between individual stations. The auto-regressive model tends to generate larger rainfall fields in space for extreme precipitation than observed, particularly in summer. The weather generator based on nearest-neighbor resampling reproduces the observed daily and multiday (5, 10 and 20) extreme events in a similar magnitude. Improvements in performance regarding wet frequencies and transition probabilities are recommended for both models.
KW - Rainfall generation
KW - Rainfall occurrence
KW - Multi-site stochastic weather
KW - generator
KW - Resampling weather generator
KW - Time series analysis
Y1 - 2021
U6 - https://doi.org/10.1016/j.jhydrol.2021.126544
SN - 0022-1694
SN - 1879-2707
VL - 601
PB - Elsevier
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Yan, Jiawei
A1 - Frøkjær, Emil Egede
A1 - Engelbrekt, Christian
A1 - Leimkühler, Silke
A1 - Ulstrup, Jens
A1 - Wollenberger, Ulla
A1 - Xiao, Xinxin
A1 - Zhang, Jingdong
T1 - Voltammetry and single-molecule in situ scanning tunnelling microscopy of the redox metalloenzyme human sulfite oxidase
JF - ChemElectroChem
N2 - Human sulfite oxidase (hSO) is a homodimeric two-domain enzyme central in the biological sulfur cycle. A pyranopterin molybdenum cofactor (Moco) is the catalytic site and a heme b(5) group located in the N-terminal domain. The two domains are connected by a flexible linker region. Electrons produced at the Moco in sulfite oxidation, are relayed via heme b(5) to electron acceptors or an electrode surface. Inter-domain conformational changes between an open and a closed enzyme conformation, allowing "gated" electron transfer has been suggested. We first recorded cyclic voltammetry (CV) of hSO on single-crystal Au(111)-electrode surfaces modified by self-assembled monolayers (SAMs) both of a short rigid thiol, cysteamine and of a longer structurally flexible thiol, omega-amino-octanethiol (AOT). hSO on cysteamine SAMs displays a well-defined pair of voltammetric peaks around -0.207 V vs. SCE in the absence of sulfite substrate, but no electrocatalysis. hSO on AOT SAMs displays well-defined electrocatalysis, but only "fair" quality voltammetry in the absence of sulfite. We recorded next in situ scanning tunnelling spectroscopy (STS) of hSO on AOT modified Au(111)-electrodes, disclosing, a 2-5 % surface coverage of strong molecular scale contrasts, assigned to single hSO molecules, notably with no contrast difference in the absence and presence of sulfite. In situ STS corroborated this observation with a sigmoidal tunnelling current/overpotential correlation.
KW - cyclic voltammetry
KW - human sulfite oxidase
KW - in situ scanning
KW - tunnelling spectroscopy
KW - self-assembled molecular monolayers
KW - single-crystal gold electrodes
Y1 - 2021
U6 - https://doi.org/10.1002/celc.202001258
SN - 2196-0216
VL - 8
IS - 1
SP - 164
EP - 171
PB - Wiley-VCH
CY - Weinheim
ER -
TY - JOUR
A1 - Kleinpeter, Erich
A1 - Heydenreich, Matthias
A1 - Shainyan, Bagrat A.
T1 - At the experimental limit of the NMR conformational analysis
BT - Si-29 and C-13 NMR study of the conformational equilibrium of 1-phenyl-1-tert-butylsilacyclohexane
JF - Organic letters
N2 - The low temperature (95 K) NMR study of 1-Ph-1-t-Bu-silacyclohexane (1) showed the conformational equilibrium to be extremely one-sided toward thePh(ax),t-Bueq conformer. The barrier to interconversion has been measured (4.2-4.6 kcal/mol) and the conformational equilibrium [Delta nu = 1990.64 ppm (Si-29), 618.9 ppm (C-13), 1-Ph-ax:1-Pheq = (95.6-96.6%):(3.4-4.4%), K = 25 +/- 3, Delta G degrees = -RT ln K = 0.58-0.63 kcal/mol] analyzed. The assignment and quantification of the NMR signals is supported by MP2 and DFT calculations.
Y1 - 2021
U6 - https://doi.org/10.1021/acs.orglett.0c03878
SN - 1523-7060
SN - 1523-7052
VL - 23
IS - 2
SP - 405
EP - 409
PB - American Chemical Society
CY - Washington
ER -
TY - JOUR
A1 - Yadav, Himanshu
A1 - Husain, Samar
A1 - Futrell, Richard
T1 - Do dependency lengths explain constraints on crossing dependencies?
JF - Linguistics vanguard : multimodal online journal
N2 - In syntactic dependency trees, when arcs are drawn from syntactic heads to dependents, they rarely cross. Constraints on these crossing dependencies are critical for determining the syntactic properties of human language, because they define the position of natural language in formal language hierarchies. We study whether the apparent constraints on crossing syntactic dependencies in natural language might be explained by constraints on dependency lengths (the linear distance between heads and dependents). We compare real dependency trees from treebanks of 52 languages against baselines of random trees which are matched with the real trees in terms of their dependency lengths. We find that these baseline trees have many more crossing dependencies than real trees, indicating that a constraint on dependency lengths alone cannot explain the empirical rarity of crossing dependencies. However, we find evidence that a combined constraint on dependency length and the rate of crossing dependencies might be able to explain two of the most-studied formal restrictions on dependency trees: gap degree and well-nestedness.
KW - crossing dependencies
KW - dependency length
KW - dependency treebanks
KW - efficiency
KW - language processing
KW - syntax
Y1 - 2021
U6 - https://doi.org/10.1515/lingvan-2019-0070
SN - 2199-174X
VL - 7
PB - De Gruyter Mouton
CY - Berlin ; New York, NY
ER -
TY - JOUR
A1 - Cano Crespo, Ana
A1 - Traxl, Dominik
A1 - Thonicke, Kirsten
T1 - Spatio-temporal patterns of extreme fires in Amazonian forests
JF - European physical journal special topics
N2 - Fires are a fundamental part of the Earth System. In the last decades, they have been altering ecosystem structure, biogeochemical cycles and atmospheric composition with unprecedented rapidity. In this study, we implement a complex networks-based methodology to track individual fires over space and time. We focus on extreme fires-the 5% most intense fires-in the tropical forests of the Brazilian Legal Amazon over the period 2002-2019. We analyse the interannual variability in the number and spatial patterns of extreme forest fires in years with diverse climatic conditions and anthropogenic pressure to examine potential synergies between climate and anthropogenic drivers. We observe that major droughts, that increase forest flammability, co-occur with high extreme fire years but also that it is fundamental to consider anthropogenic activities to understand the distribution of extreme fires. Deforestation fires, fires escaping from managed lands, and other types of forest degradation and fragmentation provide the ignition sources for fires to ignite in the forests. We find that all extreme forest fires identified are located within a 0.5-km distance from forest edges, and up to 56% of them are within a 1-km distance from roads (which increases to 73% within 5 km), showing a strong correlation that defines spatial patterns of extreme fires.
Y1 - 2021
U6 - https://doi.org/10.1140/epjs/s11734-021-00164-3
SN - 1951-6355
SN - 1951-6401
VL - 230
IS - 14-15
SP - 3033
EP - 3044
PB - Springer
CY - Berlin ; Heidelberg
ER -
TY - JOUR
A1 - Tadjoung Waffo, Armel Franklin
A1 - Mitrova, Biljana
A1 - Tiedemann, Kim
A1 - Iobbi-Nivol, Chantal
A1 - Leimkühler, Silke
A1 - Wollenberger, Ulla
T1 - Electrochemical trimethylamine n-oxide biosensor with enzyme-based oxygen-scavenging membrane for long-term operation under ambient air
JF - Biosensors : open access journal
N2 - An amperometric trimethylamine N-oxide (TMAO) biosensor is reported, where TMAO reductase (TorA) and glucose oxidase (GOD) and catalase (Cat) were immobilized on the electrode surface, enabling measurements of mediated enzymatic TMAO reduction at low potential under ambient air conditions. The oxygen anti-interference membrane composed of GOD, Cat and polyvinyl alcohol (PVA) hydrogel, together with glucose concentration, was optimized until the O-2 reduction current of a Clark-type electrode was completely suppressed for at least 3 h. For the preparation of the TMAO biosensor, Escherichia coli TorA was purified under anaerobic conditions and immobilized on the surface of a carbon electrode and covered by the optimized O-2 scavenging membrane. The TMAO sensor operates at a potential of -0.8 V vs. Ag/AgCl (1 M KCl), where the reduction of methylviologen (MV) is recorded. The sensor signal depends linearly on TMAO concentrations between 2 mu M and 15 mM, with a sensitivity of 2.75 +/- 1.7 mu A/mM. The developed biosensor is characterized by a response time of about 33 s and an operational stability over 3 weeks. Furthermore, measurements of TMAO concentration were performed in 10% human serum, where the lowest detectable concentration is of 10 mu M TMAO.
KW - trimethylamine N-oxide
KW - biosensor
KW - TMAO-reductase
KW - oxygen scavenger
KW - immobilized enzyme
KW - multienzyme electrode
KW - viologen
Y1 - 2021
U6 - https://doi.org/10.3390/bios11040098
SN - 2079-6374
VL - 11
IS - 4
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Thomas, Timon
A1 - Pfrommer, Christoph
A1 - Pakmor, Rüdiger
T1 - A finite volume method for two-moment cosmic ray hydrodynamics on a moving mesh
JF - Monthly notices of the Royal Astronomical Society
N2 - We present a new numerical algorithm to solve the recently derived equations of two-moment cosmic ray hydrodynamics (CRHD). The algorithm is implemented as a module in the moving mesh AREPO code. Therein, the anisotropic transport of cosmic rays (CRs) along magnetic field lines is discretized using a path-conservative finite volume method on the unstructured time-dependent Voronoi mesh of AREPO. The interaction of CRs and gyroresonant Alfven waves is described by short time-scale source terms in the CRHD equations. We employ a custom-made semi-implicit adaptive time stepping source term integrator to accurately integrate this interaction on the small light-crossing time of the anisotropic transport step. Both the transport and the source term integration step are separated from the evolution of the magnetohydrodynamical equations using an operator split approach. The new algorithm is tested with a variety of test problems, including shock tubes, a perpendicular magnetized discontinuity, the hydrodynamic response to a CR overpressure, CR acceleration of a warm cloud, and a CR blast wave, which demonstrate that the coupling between CR and magnetohydrodynamics is robust and accurate. We demonstrate the numerical convergence of the presented scheme using new linear and non-linear analytic solutions.
KW - hydrodynamics
KW - MHD
KW - methods: numerical
KW - cosmic rays
Y1 - 2021
U6 - https://doi.org/10.1093/mnras/stab397
SN - 0035-8711
SN - 1365-2966
VL - 503
IS - 2
SP - 2242
EP - 2264
PB - Oxford University Press
CY - Oxford
ER -
TY - JOUR
A1 - Drathschmidt, Nicolas
T1 - Den Austausch fördern
BT - Wissensmanagement : Chancen und Herausforderungen bei der
Einführung
JF - Kommune 21 : e-Government, Internet und Informationstechnik
N2 - Eine große Herausforderung für die öffentliche Verwaltung ist es, Wissen effektiv zu erhalten und untereinander auszutauschen. Eine Organisationsuntersuchung in einem brandenburgischen Landkreis zeigt, welche Chancen kommunales Wissensmanagement bereithält.
KW - Panorama
KW - Wissensmanagement
Y1 - 2021
UR - https://www.kommune21.de/meldung_35800_Den+Austausch+f%C3%B6rdern.pdf
SN - 1618-2901
VL - 21
IS - 3
SP - 12
EP - 14
PB - K21 media GmbH
CY - Tübingen
ER -
TY - JOUR
A1 - Pikovskij, Arkadij
T1 - Synchronization of oscillators with hyperbolic chaotic phases
JF - Izvestija vysšich učebnych zavedenij : naučno-techničeskij žurnal = Izvestiya VUZ. Prikladnaja nelinejnaja dinamika = Applied nonlinear dynamics
N2 - Topic and aim. Synchronization in populations of coupled oscillators can be characterized with order parameters that describe collective order in ensembles. A dependence of the order parameter on the coupling constants is well-known for coupled periodic oscillators. The goal of the study is to extend this analysis to ensembles of oscillators with chaotic phases, moreover with phases possessing hyperbolic chaos. Models and methods. Two models are studied in the paper. One is an abstract discrete-time map, composed with a hyperbolic Bernoulli transformation and with Kuramoto dynamics. Another model is a system of coupled continuous-time chaotic oscillators, where each individual oscillator has a hyperbolic attractor of Smale-Williams type. Results. The discrete-time model is studied with the Ott-Antonsen ansatz, which is shown to be invariant under the application of the Bernoulli map. The analysis of the resulting map for the order parameter shows, that the asynchronouis state is always stable, but the synchronous one becomes stable above a certain coupling strength. Numerical analysis of the continuous-time model reveals a complex sequence of transitions from an asynchronous state to a completely synchronous hyperbolic chaos, with intermediate stages that include regimes with periodic in time mean field, as well as with weakly and strongly irregular mean field variations. Discussion. Results demonstrate that synchronization of systems with hyperbolic chaos of phases is possible, although a rather strong coupling is required. The approach can be applied to other systems of interacting units with hyperbolic chaotic dynamics.
N2 - Тема и цель. Синхронизация в популяциях связанных осцилляторов может быть охарактеризована параметрами порядка, описывающими коллективный порядок в ансамблях. Зависимость параметра порядка от коэффициентов связи хорошо известна для связанных периодических осцилляторов. Целью данного исследования является обобщение этого анализа на ансамбли осцилляторов с хаотическими фазами, а именно, с фазами, распределёнными на гиперболическом аттракторе. Модели и методы. В работе исследуются две модели. Первая – абстрактное отображение в дискретном времени, составленное из гиперболического преобразования Бернулли и динамики Курамото. Вторая – это система связанных хаотических осцилляторов в непрерывном времени, где каждый отдельный осциллятор имеет гиперболический аттрактор типа Смейла–Вильямса. Результаты. Модель в дискретном времени изучается с помощью подхода Отта–Антонсена, который, как показано, инвариантен при применении отображения Бернулли. Анализ полученного отображения по параметрам порядка показывает, что асинхронное состояние всегда устойчиво, а синхронное состояние становится устойчивым выше определенной силы связи. Численный анализ модели в непрерывном времени показывает сложную последовательность переходов из асинхронного состояния в полностью синхронный гиперболический хаос с промежуточными стадиями, которые включают режимы с периодическим во времени средним полем, а также со слабо и сильно нерегулярными вариациями среднего поля.
Обсуждение. Результаты показывают, что синхронизация систем с гиперболическим фазовым хаосом возможна, хотя требуется довольно сильная связь. Данный подход может быть применен и к другим системам взаимодействующих звеньев с гиперболической хаотической динамикой.
T2 - Синхронизация осцилляторов с гиперболическими хаотическими фазами
KW - hyperbolic attractor
KW - synchronization
KW - collective dynamics
KW - иперболический аттрактор
KW - синхронизация
KW - оллективная динамика
Y1 - 2021
U6 - https://doi.org/10.18500/0869-6632-2021-29-1-78-87
SN - 0869-6632
SN - 2542-1905
VL - 29
IS - 1
SP - 78
EP - 87
PB - Saratov State University
CY - Saratov
ER -
TY - JOUR
A1 - Rosenau, Philip
A1 - Pikovskij, Arkadij
T1 - Waves in strongly nonlinear Gardner-like equations on a lattice
JF - Nonlinearity / the Institute of Physics and the London Mathematical Society
N2 - We introduce and study a family of lattice equations which may be viewed either as a strongly nonlinear discrete extension of the Gardner equation, or a non-convex variant of the Lotka-Volterra chain. Their deceptively simple form supports a very rich family of complex solitary patterns. Some of these patterns are also found in the quasi-continuum rendition, but the more intriguing ones, like interlaced pairs of solitary waves, or waves which may reverse their direction either spontaneously or due a collision, are an intrinsic feature of the discrete realm.
KW - nonlinear lattice
KW - solitary wave
KW - Gardner equation
KW - compacton
Y1 - 2021
U6 - https://doi.org/10.1088/1361-6544/ac0f51
SN - 0951-7715
SN - 1361-6544
VL - 34
IS - 8
SP - 5872
EP - 5896
PB - IOP Publ. Ltd.
CY - Bristol
ER -
TY - JOUR
A1 - Hickmann, Thomas
A1 - Widerberg, Oscar
A1 - Lederer, Markus
A1 - Pattberg, Philipp H.
T1 - The United Nations Framework Convention on Climate Change Secretariat as an orchestrator in global climate policymaking
JF - International review of administrative sciences : an international journal of comparative public administration
N2 - Scholars have recently devoted increasing attention to the role and function of international bureaucracies in global policymaking. Some of them contend that international public officials have gained significant political influence in various policy fields. Compared to other international bureaucracies, the political leeway of the Secretariat of the United Nations Framework Convention on Climate Change has been considered rather limited. Due to the specific problem structure of the policy domain of climate change, national governments endowed this intergovernmental treaty secretariat with a relatively narrow mandate. However, this article argues that in the past few years, the United Nations Framework Convention on Climate Change Secretariat has gradually loosened its straitjacket and expanded its original spectrum of activity by engaging different sub-national and non-state actors into a policy dialogue using facilitative orchestration as a mode of governance. The present article explores the recent evolution of the United Nations Framework Convention on Climate Change Secretariat and investigates the way in which it initiates, guides, broadens and strengthens sub-national and non-state climate actions to achieve progress in the international climate negotiations.
Points for practitioners
The Secretariat of the United Nations Framework Convention on Climate Change has lately adopted new roles and functions in global climate policymaking. While previously seen as a rather technocratic body that, first and foremost, serves national governments, the Climate Secretariat increasingly interacts with sub-national governments, civil society organizations and private companies to push the global response to climate change forward. We contend that the Climate Secretariat can contribute to global climate policymaking by coordinating and steering the initiatives of non-nation-state actors towards coherence and good practice.
KW - climate change
KW - environmental policymaking
KW - intergovernmental relations
KW - international bureaucracies
KW - sub-national and non-state actors
Y1 - 2021
U6 - https://doi.org/10.1177/0020852319840425
SN - 0020-8523
SN - 1461-7226
VL - 87
IS - 1
SP - 21
EP - 38
PB - Sage
CY - Los Angeles, Calif. [u.a.]
ER -
TY - JOUR
A1 - Wick, Kristin
A1 - Kriemler, Susi
A1 - Granacher, Urs
T1 - Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children
JF - Journal of strength and conditioning research : the research journal of the NSCA
N2 - Wick, K, Kriemler, S, and Granacher, U. Effects of a strength-dominated exercise program on physical fitness and cognitive performance in preschool children. J Strength Cond Res 35(4): 983-990, 2021-Childhood is characterized by high neuroplasticity that affords qualitative rather than quantitative components of physical activity to maximize the potential to sufficiently develop motor skills and foster long-term engagement in regular physical activity. This study examined the effects of an integrative strength-dominated exercise program on measures of physical fitness and cognitive performance in preschool children. Children aged 4-6 years from 3 kindergartens were randomized into an intervention (INT) group (n = 32) or a control group (n = 22). The 10-week intervention period was conducted 3 times per week (each session lasted 30 minutes) and included exercises for the promotion of muscle strength and power, coordination, and balance. Pre and post training, tests were conducted for the assessment of muscle strength (i.e., handgrip strength), muscle power (i.e., standing long jump), balance (i.e., timed single-leg stand), coordination (hopping on right/left leg), and attentional span (i.e., "Konzentrations-Handlungsverfahren fur Vorschulkinder" [concentration-action procedure for preschoolers]). Results from 2 x 2 repeated-measures analysis of covariance revealed a significant (p <= 0.05) and near significant (p = 0.051) group x time interaction for the standing long jump test and the Konzentrations-Handlungsverfahren. Post hoc tests showed significant pre-post changes for the INT (p < 0.001; d = 1.53) but not the CON (p = 0.72; d = 0.83). Our results indicate that a 10-week strength-dominated exercise program increased jump performance with a concomitant trend toward improvements in attentional capacity of preschool children. Thus, we recommend implementing this type of exercise program for preschoolers.
KW - motor skills
KW - cognitive skills
KW - attention
KW - kindergarten
KW - structured
KW - physical activity program
Y1 - 2021
U6 - https://doi.org/10.1519/JSC.0000000000003942
SN - 1064-8011
SN - 1533-4287
VL - 35
IS - 4
SP - 983
EP - 990
PB - Lippincott Williams & Wilkins
CY - Philadelphia
ER -
TY - JOUR
A1 - Combi, Carlo
A1 - Oliboni, Barbara
A1 - Weske, Mathias
A1 - Zerbato, Francesca
T1 - Seamless conceptual modeling of processes with transactional and analytical data
JF - Data & knowledge engineering
N2 - In the field of Business Process Management (BPM), modeling business processes and related data is a critical issue since process activities need to manage data stored in databases. The connection between processes and data is usually handled at the implementation level, even if modeling both processes and data at the conceptual level should help designers in improving business process models and identifying requirements for implementation. Especially in data -and decision-intensive contexts, business process activities need to access data stored both in databases and data warehouses. In this paper, we complete our approach for defining a novel conceptual view that bridges process activities and data. The proposed approach allows the designer to model the connection between business processes and database models and define the operations to perform, providing interesting insights on the overall connected perspective and hints for identifying activities that are crucial for decision support.
KW - Conceptual modeling
KW - Business process modeling
KW - BPMN
KW - Data modeling
KW - Data warehouse
KW - Decision support
Y1 - 2021
U6 - https://doi.org/10.1016/j.datak.2021.101895
SN - 0169-023X
SN - 1872-6933
VL - 134
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Rüther, Ferenc Darius
A1 - Sebode, Marcial
A1 - Lohse, Ansgar W.
A1 - Wernicke, Sarah
A1 - Böttinger, Erwin
A1 - Casar, Christian
A1 - Braun, Felix
A1 - Schramm, Christoph
T1 - Mobile app requirements for patients with rare liver diseases
BT - a single center survey for the ERN RARE-LIVER
JF - Clinics and research in hepatology and gastroenterology
N2 - Background:
More patient data are needed to improve research on rare liver diseases. Mobile health apps enable an exhaustive data collection. Therefore, the European Reference Network on Hepatological diseases (ERN RARE-LIVER) intends to implement an app for patients with rare liver diseases communicating with a patient registry, but little is known about which features patients and their healthcare providers regard as being useful.
Aims:
This study aimed to investigate how an app for rare liver diseases would be accepted, and to find out which features are considered useful.
Methods:
An anonymous survey was conducted on adult patients with rare liver diseases at a single academic, tertiary care outpatient-service. Additionally, medical experts of the ERN working group on autoimmune hepatitis were invited to participate in an online survey.
Results:
In total, the responses from 100 patients with autoimmune (n = 90) or other rare (n = 10) liver diseases and 32 experts were analyzed. Patients were convinced to use a disease specific app (80%) and expected some benefit to their health (78%) but responses differed signifi-cantly between younger and older patients (93% vs. 62%, p < 0.001; 88% vs. 64%, p < 0.01). Comparing patients' and experts' feedback, patients more often expected a simplified healthcare pathway (e.g. 89% vs. 59% (p < 0.001) wanted access to one's own medical records), while healthcare providers saw the benefit mainly in improving compliance and treatment outcome (e.g. 93% vs. 31% (p < 0.001) and 70% vs. 21% (p < 0.001) expected the app to reduce mistakes in taking medication and improve quality of life, respectively).
KW - Primary sclerosing cholangitis
KW - Primary biliary cholangitis
KW - Autoimmune
KW - hepatitis
KW - European reference networks
KW - Mobile applications
KW - Patient
KW - reported out-come measures
Y1 - 2021
U6 - https://doi.org/10.1016/j.clinre.2021.101760
SN - 2210-7401
SN - 2210-741X
VL - 45
IS - 6
PB - Elsevier Masson
CY - Amsterdam
ER -
TY - JOUR
A1 - Mawire, Phillip
A1 - Mozirandi, Winnie
A1 - Heydenreich, Matthias
A1 - Chi, Godloves Fru
A1 - Mukanganyama, Stanley
T1 - Isolation and antimicrobial activities of phytochemicals from Parinari curatellifolia (Chrysobalanaceae)
JF - Advances in pharmacological and pharmaceutical sciences
N2 - The widespread use of antimicrobial agents to treat infectious diseases has led to the emergence of antibiotic resistant pathogens. Plants have played a central role in combating many ailments in humans, and Parinari curatellifolia has been used for medicinal purposes. Seven extracts from P. curatellifolia leaves were prepared using serial exhaustive extraction of nonpolar to polar solvents. The microbroth dilution method was used to evaluate antimicrobial bioactivities of extracts. Five of the extracts were significantly active against at least one test microbe. Mycobacterium smegmatis was the most susceptible to most extracts. The methanol and ethanol extracts were the most active against M. smegmatis with an MIC of 25 mu g/mL. The hexane extract was the most active against Candida krusei with an MIC of 25 mu g/mL. None of the extracts significantly inhibited growth of Klebsiella pneumoniae and Staphylococcus aureus. Active extracts were selected for fractionation and isolation of pure compounds using gradient elution column chromatography. TLC analyses was carried out for pooling fractions of similar profiles. A total of 43 pools were obtained from 428 fractions. Pools 7 and 10 were selected for further isolation of single compounds. Four compounds, Pc4963r, Pc4962w, Pc6978p, and Pc6978o, were isolated. Evaluation of antimicrobial activities of Pc4963r, Pc4962w, and Pc6978p showed that the compounds were most active against C. krusei with MFC values ranging from 50 to 100 mu g/mL. Only Pc6978p was shown to be pure. Using spectroscopic analyses, the structure of Pc6978p was determined to be beta-sitosterol. The antifungal effects of beta-sitosterol were evaluated against C. krusei in vitro and on fabrics. Results showed that beta-sitosterol reduced the growth of C. krusei attached to Mendy fabric by 83%. Therefore, P. curatellifolia can be a source of lead compounds for prospective development of novel antimicrobial agents. Further work needs to be done to improve the antifungal activity of the isolated compound using quantitative structure-activity relationships.
Y1 - 2021
U6 - https://doi.org/10.1155/2021/8842629
SN - 2633-4682
SN - 2633-4690
PB - Hindawi
CY - London
ER -
TY - JOUR
A1 - Rudolph, Max
A1 - Schmeer, Christian
A1 - Günther, Madlen
A1 - Woitke, Florus
A1 - Kathner-Schaffert, Carolin
A1 - Karapetow, Lina
A1 - Lindner, Julia
A1 - Lehmann, Thomas
A1 - Jirikowski, Gustav
A1 - Witte, Otto W.
A1 - Redecker, Christoph
A1 - Keiner, Silke
T1 - Microglia-mediated phagocytosis of apoptotic nuclei is impaired in the adult murine hippocampus after stroke
JF - Glia
N2 - Following stroke, neuronal death takes place both in the infarct region and in brain areas distal to the lesion site including the hippocampus. The hippocampus is critically involved in learning and memory processes and continuously generates new neurons. Dysregulation of adult neurogenesis may be associated with cognitive decline after a stroke lesion. In particular, proliferation of precursor cells and the formation of new neurons are increased after lesion. Within the first week, many new precursor cells die during development. How dying precursors are removed from the hippocampus and to what extent phagocytosis takes place after stroke is still not clear. Here, we evaluated the effect of a prefrontal stroke lesion on the phagocytic activity of microglia in the dentate gyrus (DG) of the hippocampus. Three-months-old C57BL/6J mice were injected once with the proliferation marker BrdU (250 mg/kg) 6 hr after a middle cerebral artery occlusion or sham surgery. The number of apoptotic cells and the phagocytic capacity of the microglia were evaluated by means of immunohistochemistry, confocal microscopy, and 3D-reconstructions. We found a transient but significant increase in the number of apoptotic cells in the DG early after stroke, associated with impaired removal by microglia. Interestingly, phagocytosis of newly generated precursor cells was not affected. Our study shows that a prefrontal stroke lesion affects phagocytosis of apoptotic cells in the DG, a region distal to the lesion core. Whether disturbed phagocytosis might contribute to inflammatory- and maladaptive processes including cognitive impairment following stroke needs to be further investigated.
KW - activated caspase 3
KW - dentate gyrus
KW - MCAO
KW - neurogenesis
KW - pyknotic cells
Y1 - 2021
U6 - https://doi.org/10.1002/glia.24009
SN - 0894-1491
SN - 1098-1136
VL - 69
IS - 8
SP - 2006
EP - 2022
PB - Wiley-Blackwell
CY - Hoboken
ER -
TY - JOUR
A1 - Fitjar, Camilla L.
A1 - Rønneberg, Vibeke
A1 - Nottbusch, Guido
A1 - Torrance, Mark
T1 - Learning handwriting
BT - factors affecting pen-movement fluency in beginning writers
JF - Frontiers in psychology / Frontiers Research Foundation
N2 - Skilled handwriting of single letters is associated not only with a neat final product but also with fluent pen-movement, characterized by a smooth pen-tip velocity profile. Our study explored fluency when writing single letters in children who were just beginning to learn to handwrite, and the extent to which this was predicted by the children's pen-control ability and by their letter knowledge. 176 Norwegian children formed letters by copying and from dictation (i.e., in response to hearing letter sounds). Performance on these tasks was assessed in terms of the counts of velocity inversions as the children produced sub-letter features that would be produced by competent handwriters as a single, smooth (ballistic) action. We found that there was considerable variation in these measures across writers, even when producing well-formed letters. Children also copied unfamiliar symbols, completed various pen-control tasks (drawing lines, circles, garlands, and figure eights), and tasks that assessed knowledge of letter sounds and shapes. After controlling for pen-control ability, pen-movement fluency was affected by letter knowledge (specifically children's performance on a task that required selecting graphemes on the basis of their sound). This was the case when children retrieved letter forms from dictated letter sounds, but also when directly copying letters and, unexpectedly, when copying unfamiliar symbols. These findings suggest that familiarity with a letter affects movement fluency during letter production but may also point towards a more general ability to process new letter-like symbols in children with good letter knowledge.
KW - children
KW - handwriting
KW - fluency
KW - pen-control
KW - letter knowledge
Y1 - 2021
U6 - https://doi.org/10.3389/fpsyg.2021.663829
SN - 1664-1078
VL - 12
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Bekir, Marek
A1 - Jelken, Joachim
A1 - Jung, Se-Hyeong
A1 - Pich, Andrij
A1 - Pacholski, Claudia
A1 - Kopyshev, Alexey
A1 - Santer, Svetlana
T1 - Dual responsiveness of microgels induced by single light stimulus
JF - Applied physics letters
N2 - We report on the multiple response of microgels triggered by a single optical stimulus. Under irradiation, the volume of the microgels is reversibly switched by more than 20 times. The irradiation initiates two different processes: photo-isomerization of the photo-sensitive surfactant, which forms a complex with the anionic microgel, rendering it photo-responsive; and local heating due to a thermo-plasmonic effect within the structured gold layer on which the microgel is deposited. The photo-responsivity is related to the reversible accommodation/release of the photo-sensitive surfactant depending on its photo-isomerization state, while the thermo-sensitivity is intrinsically built in. We show that under exposure to green light, the thermo-plasmonic effect generates a local hot spot in the gold layer, resulting in the shrinkage of the microgel. This process competes with the simultaneous photo-induced swelling. Depending on the position of the laser spot, the spatiotemporal control of reversible particle shrinking/swelling with a predefined extent on a per-second base can be implemented.
Y1 - 2021
U6 - https://doi.org/10.1063/5.0036376
SN - 0003-6951
SN - 1077-3118
VL - 118
IS - 9
PB - American Institute of Physics
CY - Melville
ER -
TY - JOUR
A1 - Freitas da Cruz, Harry
A1 - Pfahringer, Boris
A1 - Martensen, Tom
A1 - Schneider, Frederic
A1 - Meyer, Alexander
A1 - Böttinger, Erwin
A1 - Schapranow, Matthieu-Patrick
T1 - Using interpretability approaches to update "black-box" clinical prediction models
BT - an external validation study in nephrology
JF - Artificial intelligence in medicine : AIM
N2 - Despite advances in machine learning-based clinical prediction models, only few of such models are actually deployed in clinical contexts. Among other reasons, this is due to a lack of validation studies. In this paper, we present and discuss the validation results of a machine learning model for the prediction of acute kidney injury in cardiac surgery patients initially developed on the MIMIC-III dataset when applied to an external cohort of an American research hospital. To help account for the performance differences observed, we utilized interpretability methods based on feature importance, which allowed experts to scrutinize model behavior both at the global and local level, making it possible to gain further insights into why it did not behave as expected on the validation cohort. The knowledge gleaned upon derivation can be potentially useful to assist model update during validation for more generalizable and simpler models. We argue that interpretability methods should be considered by practitioners as a further tool to help explain performance differences and inform model update in validation studies.
KW - Clinical predictive modeling
KW - Nephrology
KW - Validation
KW - Interpretability
KW - methods
Y1 - 2021
U6 - https://doi.org/10.1016/j.artmed.2020.101982
SN - 0933-3657
SN - 1873-2860
VL - 111
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Wehrhan, Marc
A1 - Puppe, Daniel
A1 - Kaczorek, Danuta
A1 - Sommer, Michael
T1 - Spatial patterns of aboveground phytogenic Si stocks in a grass-dominated catchment
BT - results from UAS-based high-resolution remote sensing
JF - Biogeosciences : BG
N2 - Various studies have been performed to quantify silicon (Si) stocks in plant biomass and related Si fluxes in terrestrial biogeosystems. Most studies are deliberately designed on the plot scale to ensure low heterogeneity in soils and plant composition, hence similar environmental conditions. Due to the immanent spatial soil variability, the transferability of results to larger areas, such as catchments, is therefore limited. However, the emergence of new technical features and increasing knowledge on details in Si cycling lead to a more complex picture at landscape and catchment scales. Dynamic and static soil properties change along the soil continuum and might influence not only the species composition of natural vegetation but also its biomass distribution and related Si stocks. Maximum likelihood (ML) classification was applied to multispectral imagery captured by an unmanned aerial system (UAS) aiming at the identification of land cover classes (LCCs). Subsequently, the normalized difference vegetation index (NDVI) and ground-based measurements of biomass were used to quantify aboveground Si stocks in two Si-accumulating plants (Calamagrostis epige-jos and Phragmites australis) in a heterogeneous catchment and related corresponding spatial patterns of these stocks to soil properties. We found aboveground Si stocks of C. epige-jos and P. australis to be surprisingly high (maxima of Si stocks reach values up to 98 g Sim(-2)), i.e. comparable to or markedly exceeding reported values for the Si storage in aboveground vegetation of various terrestrial ecosystems. We further found spatial patterns of plant aboveground Si stocks to reflect spatial heterogeneities in soil properties. From our results, we concluded that (i) aboveground biomass of plants seems to be the main factor of corresponding phytogenic Si stock quantities, and (ii) a detection of biomass heterogeneities via UAS-based remote sensing represents a promising tool for the quantification of lifelike phytogenic Si pools at landscape scales.
Y1 - 2021
U6 - https://doi.org/10.5194/bg-18-5163-2021
SN - 1726-4170
SN - 1726-4189
VL - 18
IS - 18
SP - 5163
EP - 5183
PB - Copernicus
CY - Göttingen
ER -
TY - JOUR
A1 - Stone, Kate
A1 - Lago, Sol
A1 - Schad, Daniel
T1 - Divergence point analyses of visual world data
BT - applications to bilingual research
JF - Bilingualism : language and cognition
N2 - Much work has shown that differences in the timecourse of language processing are central to comparing native (L1) and non-native (L2) speakers. However, estimating the onset of experimental effects in timecourse data presents several statistical problems including multiple comparisons and autocorrelation. We compare several approaches to tackling these problems and illustrate them using an L1-L2 visual world eye-tracking dataset. We then present a bootstrapping procedure that allows not only estimation of an effect onset, but also of a temporal confidence interval around this divergence point. We describe how divergence points can be used to demonstrate timecourse differences between speaker groups or between experimental manipulations, two important issues in evaluating L2 processing accounts. We discuss possible extensions of the bootstrapping procedure, including determining divergence points for individual speakers and correlating them with individual factors like L2 exposure and proficiency. Data and an analysis tutorial are available at https://osf.io/exbmk/.
KW - divergence point analyses
KW - non-parametric approaches
KW - bootstrapping
KW - visual world eye-tracking
KW - bilingualism
Y1 - 2021
U6 - https://doi.org/10.1017/S1366728920000607
SN - 1366-7289
SN - 1469-1841
VL - 24
IS - 5
SP - 833
EP - 841
PB - Cambridge Univ. Press
CY - Cambridge
ER -
TY - JOUR
A1 - Schaller, Jörg
A1 - Puppe, Daniel
A1 - Kaczorek, Danuta
A1 - Ellerbrock, Ruth
A1 - Sommer, Michael
T1 - Silicon cycling in soils revisited
JF - Plants : open access journal
N2 - Silicon (Si) speciation and availability in soils is highly important for ecosystem functioning, because Si is a beneficial element for plant growth. Si chemistry is highly complex compared to other elements in soils, because Si reaction rates are relatively slow and dependent on Si species. Consequently, we review the occurrence of different Si species in soil solution and their changes by polymerization, depolymerization, and condensation in relation to important soil processes. We show that an argumentation based on thermodynamic endmembers of Si dependent processes, as currently done, is often difficult, because some reactions such as mineral crystallization require months to years (sometimes even centuries or millennia). Furthermore, we give an overview of Si reactions in soil solution and the predominance of certain solid compounds, which is a neglected but important parameter controlling the availability, reactivity, and function of Si in soils. We further discuss the drivers of soil Si cycling and how humans interfere with these processes. The soil Si cycle is of major importance for ecosystem functioning; therefore, a deeper understanding of drivers of Si cycling (e.g., predominant speciation), human disturbances and the implication for important soil properties (water storage, nutrient availability, and micro aggregate stability) is of fundamental relevance.
KW - andosols
KW - clay neoformation
KW - crop yield
KW - land use change
KW - micro
KW - aggregate stability
KW - phytoliths
KW - sediments
KW - silicon cycling
KW - silicon
KW - extraction methods
KW - silicon pore water speciation
Y1 - 2021
U6 - https://doi.org/10.3390/plants10020295
SN - 2223-7747
VL - 10
IS - 2
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Neffe, Axel T.
A1 - Löwenberg, Candy
A1 - Lendlein, Andreas
T1 - Hydrogel networks by aliphatic dithiol Michael addition to glycidylmethacrylated gelatin
JF - MRS advances : a journal of the Materials Research Society (MRS)
N2 - Functionalization of gelatin with glycidylmethacrylate (GMA-gelatin) enables network formation employing the double bond, so that the reaction is orthogonal to the inherent functional groups in the biomacromolecule. Here, network formation by crosslinking of GMA-gelatin with hexane 1,6-dithiol or nonane 1,9-dithiol to tailor properties and enable a shape-memory effect is shown by H-1 NMR and FT-IR spectroscopy. Hydrogel swelling (460-1900 vol%) and mechanical properties (Young's modulus E = 59-512 kPa, elongation at break epsilon(b) = 44-127%) depended on the molecular composition of the networks and temperature. Increased crosslinker length, thiol:methacrylate molar ratio, and precursor concentrations led to denser networks. Change of properties with temperature suggested adoption of triple helices by gelatin chains, forming physical netpoints at lower temperatures (< 20 degrees C). However, the limited freedom of the gelatin chains to move allowed only a minimal extent of triple helices formation, as it became apparent from the related signal in wide-angle X-ray scattering and the thermal transition associated to triple helices in some networks by DSC. The presented strategy is likely transferable to other biomacromolecules, and the results suggest that too short crosslinkers may result in a significant amount of grafting rather than network formation.
Y1 - 2021
U6 - https://doi.org/10.1557/s43580-021-00136-8
SN - 2059-8521
VL - 6
IS - 33
SP - 796
EP - 800
PB - Springer Nature Switzerland AG
CY - Cham
ER -
TY - JOUR
A1 - Lau, Skadi
A1 - Maier, Anna
A1 - Braune, Steffen
A1 - Gossen, Manfred
A1 - Lendlein, Andreas
T1 - Effect of endothelial culture medium composition on platelet responses to polymeric biomaterials
JF - International journal of molecular sciences
N2 - Near-physiological in vitro thrombogenicity test systems for the evaluation of blood-contacting endothelialized biomaterials requires co-cultivation with platelets (PLT). However, the addition of PLT has led to unphysiological endothelial cell (EC) detachment in such in vitro systems. A possible cause for this phenomenon may be PLT activation triggered by the applied endothelial cell medium, which typically consists of basal medium (BM) and nine different supplements. To verify this hypothesis, the influence of BM and its supplements was systematically analyzed regarding PLT responses. For this, human platelet rich plasma (PRP) was mixed with BM, BM containing one of nine supplements, or with BM containing all supplements together. PLT adherence analysis was carried out in six-channel slides with plasma-treated cyclic olefin copolymer (COC) and poly(tetrafluoro ethylene) (PTFE, as a positive control) substrates as part of the six-channel slides in the absence of EC and under static conditions. PLT activation and aggregation were analyzed using light transmission aggregometry and flow cytometry (CD62P). Medium supplements had no effect on PLT activation and aggregation. In contrast, supplements differentially affected PLT adherence, however, in a polymer- and donor-dependent manner. Thus, the use of standard endothelial growth medium (BM + all supplements) maintains functionality of PLT under EC compatible conditions without masking the differences of PLT adherence on different polymeric substrates. These findings are important prerequisites for the establishment of a near-physiological in vitro thrombogenicity test system assessing polymer-based cardiovascular implant materials in contact with EC and PLT.
KW - cyclic olefin copolymer
KW - poly(tetrafluoroethylene)
KW - endothelial cells
KW - platelets
KW - in vitro thrombogenicity testing
Y1 - 2021
U6 - https://doi.org/10.3390/ijms22137006
SN - 1422-0067
SN - 1661-6596
VL - 22
IS - 13
PB - Molecular Diversity Preservation International
CY - Basel
ER -
TY - JOUR
A1 - Cvetković, Nada
A1 - Conrad, Tim
A1 - Lie, Han Cheng
T1 - A convergent discretization method for transition path theory for diffusion processes
JF - Multiscale modeling & simulation : a SIAM interdisciplinary journal
N2 - Transition path theory (TPT) for diffusion processes is a framework for analyzing the transitions of multiscale ergodic diffusion processes between disjoint metastable subsets of state space. Most methods for applying TPT involve the construction of a Markov state model on a discretization of state space that approximates the underlying diffusion process. However, the assumption of Markovianity is difficult to verify in practice, and there are to date no known error bounds or convergence results for these methods. We propose a Monte Carlo method for approximating the forward committor, probability current, and streamlines from TPT for diffusion processes. Our method uses only sample trajectory data and partitions of state space based on Voronoi tessellations. It does not require the construction of a Markovian approximating process. We rigorously prove error bounds for the approximate TPT objects and use these bounds to show convergence to their exact counterparts in the limit of arbitrarily fine discretization. We illustrate some features of our method by application to a process that solves the Smoluchowski equation on a triple-well potential.
KW - ergodic diffusion processes
KW - transition paths
KW - rare events
KW - Monte Carlo
KW - methods
Y1 - 2021
U6 - https://doi.org/10.1137/20M1329354
SN - 1540-3459
SN - 1540-3467
VL - 19
IS - 1
SP - 242
EP - 266
PB - Society for Industrial and Applied Mathematics
CY - Philadelphia
ER -
TY - JOUR
A1 - Klaus, Susanne
A1 - Igual Gil, Carla
A1 - Ost, Mario
T1 - Regulation of diurnal energy balance by mitokines
JF - Cellular and molecular life sciences : CMLS
N2 - The mammalian system of energy balance regulation is intrinsically rhythmic with diurnal oscillations of behavioral and metabolic traits according to the 24 h day/night cycle, driven by cellular circadian clocks and synchronized by environmental or internal cues such as metabolites and hormones associated with feeding rhythms. Mitochondria are crucial organelles for cellular energy generation and their biology is largely under the control of the circadian system. Whether mitochondrial status might also feed-back on the circadian system, possibly via mitokines that are induced by mitochondrial stress as endocrine-acting molecules, remains poorly understood. Here, we describe our current understanding of the diurnal regulation of systemic energy balance, with focus on fibroblast growth factor 21 (FGF21) and growth differentiation factor 15 (GDF15), two well-known endocrine-acting metabolic mediators. FGF21 shows a diurnal oscillation and directly affects the output of the brain master clock. Moreover, recent data demonstrated that mitochondrial stress-induced GDF15 promotes a day-time restricted anorexia and systemic metabolic remodeling as shown in UCP1-transgenic mice, where both FGF21 and GDF15 are induced as myomitokines. In this mouse model of slightly uncoupled skeletal muscle mitochondria GDF15 proved responsible for an increased metabolic flexibility and a number of beneficial metabolic adaptations. However, the molecular mechanisms underlying energy balance regulation by mitokines are just starting to emerge, and more data on diurnal patterns in mouse and man are required. This will open new perspectives into the diurnal nature of mitokines and action both in health and disease.
KW - Mitochondria
KW - FGF21
KW - GDF15
KW - Circadian rhythm
KW - Hormones
KW - Nutrition
Y1 - 2021
U6 - https://doi.org/10.1007/s00018-020-03748-9
SN - 1420-682X
SN - 1420-9071
VL - 78
IS - 7
SP - 3369
EP - 3384
PB - Springer International Publishing AG
CY - Cham (ZG)
ER -
TY - JOUR
A1 - Willner, Sven N.
A1 - Glanemann, Nicole
A1 - Levermann, Anders
T1 - Investment incentive reduced by climate damages can be restored by optimal policy
JF - Nature Communications
N2 - Increasing greenhouse gas emissions are likely to impact not only natural systems but economies worldwide. If these impacts alter future economic development, the financial losses will be significantly higher than the mere direct damages. So far, potentially aggravating investment responses were considered negligible. Here we consistently incorporate an empirically derived temperature-growth relation into the simple integrated assessment model DICE. In this framework we show that, if in the next eight decades varying temperatures impact economic growth as has been observed in the past three decades, income is reduced by similar to 20% compared to an economy unaffected by climate change. Hereof similar to 40% are losses due to growth effects of which similar to 50% result from reduced incentive to invest. This additional income loss arises from a reduced incentive for future investment in anticipation of a reduced return and not from an explicit climate protection policy. Under economically optimal climate-change mitigation, however, optimal investment would only be reduced marginally as mitigation efforts keep returns high.
Y1 - 2021
U6 - https://doi.org/10.1038/s41467-021-23547-5
SN - 2041-1723
VL - 12
IS - 1
PB - Nature Publishing Group UK
CY - London
ER -
TY - JOUR
A1 - Pasemann, Gregor
A1 - Flemming, Sven
A1 - Alonso, Sergio
A1 - Beta, Carsten
A1 - Stannat, Wilhelm
T1 - Diffusivity estimation for activator-inhibitor models
BT - theory and application to intracellular dynamics of the actin cytoskeleton
JF - Journal of nonlinear science
N2 - A theory for diffusivity estimation for spatially extended activator-inhibitor dynamics modeling the evolution of intracellular signaling networks is developed in the mathematical framework of stochastic reaction-diffusion systems. In order to account for model uncertainties, we extend the results for parameter estimation for semilinear stochastic partial differential equations, as developed in Pasemann and Stannat (Electron J Stat 14(1):547-579, 2020), to the problem of joint estimation of diffusivity and parametrized reaction terms. Our theoretical findings are applied to the estimation of effective diffusivity of signaling components contributing to intracellular dynamics of the actin cytoskeleton in the model organism Dictyostelium discoideum.
KW - Parametric drift estimation
KW - Stochastic reaction– diffusion
KW - systems
KW - Maximum likelihood estimation
KW - Actin cytoskeleton dynamics
Y1 - 2021
U6 - https://doi.org/10.1007/s00332-021-09714-4
SN - 0938-8974
SN - 1432-1467
VL - 31
IS - 3
PB - Springer
CY - New York
ER -
TY - JOUR
A1 - Schönemann, Eric
A1 - Koc, Julian
A1 - Karthäuser, Jana
A1 - Özcan, Onur
A1 - Schanzenbach, Dirk
A1 - Schardt, Lisa
A1 - Rosenhahn, Axel
A1 - Laschewsky, André
T1 - Sulfobetaine methacrylate polymers of unconventional polyzwitterion architecture and their antifouling properties
JF - Biomacromolecules : an interdisciplinary journal focused at the interface of polymer science and the biological sciences
N2 - Combining high hydrophilicity with charge neutrality, polyzwitterions are intensely explored for their high biocompatibility and low-fouling properties. Recent reports indicated that in addition to charge neutrality, the zwitterion's segmental dipole orientation is an important factor for interacting with the environment. Accordingly, a series of polysulfobetaines with a novel architecture was designed, in which the cationic and anionic groups of the zwitterionic moiety are placed at equal distances from the backbone. They were investigated by in vitro biofouling assays, covering proteins of different charges and model marine organisms. All polyzwitterion coatings reduced the fouling effectively compared to model polymer surfaces of poly(butyl methacrylate), with a nearly equally good performance as the reference polybetaine poly(3-(N-(2-(methacryloyloxy)ethyl)-N,N-dimethylammonio)propanesulfonate). The specific fouling resistance depended on the detailed chemical structure of the polyzwitterions. Still, while clearly affecting the performance, the precise dipole orientation of the sulfobetaine group in the polyzwitterions seems overall to be only of secondary importance for their antifouling behavior.
Y1 - 2021
U6 - https://doi.org/10.1021/acs.biomac.0c01705
SN - 1525-7797
SN - 1526-4602
VL - 22
IS - 4
SP - 1494
EP - 1508
PB - American Chemical Society
CY - Washington
ER -
TY - JOUR
A1 - Schröder, Jakob
A1 - Evans, Alexander
A1 - Mishurova, Tatiana
A1 - Ulbricht, Alexander
A1 - Sprengel, Maximilian
A1 - Serrano-Munoz, Itziar
A1 - Fritsch, Tobias
A1 - Kromm, Arne
A1 - Kannengießer, Thomas
A1 - Bruno, Giovanni
T1 - Diffraction-based residual stress characterization in laser additive manufacturing of metals
JF - Metals : open access journal
N2 - Laser-based additive manufacturing methods allow the production of complex metal structures within a single manufacturing step. However, the localized heat input and the layer-wise manufacturing manner give rise to large thermal gradients. Therefore, large internal stress (IS) during the process (and consequently residual stress (RS) at the end of production) is generated within the parts. This IS or RS can either lead to distortion or cracking during fabrication or in-service part failure, respectively. With this in view, the knowledge on the magnitude and spatial distribution of RS is important to develop strategies for its mitigation. Specifically, diffraction-based methods allow the spatial resolved determination of RS in a non-destructive fashion. In this review, common diffraction-based methods to determine RS in laser-based additive manufactured parts are presented. In fact, the unique microstructures and textures associated to laser-based additive manufacturing processes pose metrological challenges. Based on the literature review, it is recommended to (a) use mechanically relaxed samples measured in several orientations as appropriate strain-free lattice spacing, instead of powder, (b) consider that an appropriate grain-interaction model to calculate diffraction-elastic constants is both material- and texture-dependent and may differ from the conventionally manufactured variant. Further metrological challenges are critically reviewed and future demands in this research field are discussed.
KW - laser-based additive manufacturing
KW - residual stress analysis
KW - X-ray and
KW - neutron diffraction
KW - diffraction-elastic constants
KW - strain-free lattice
KW - spacing
Y1 - 2021
U6 - https://doi.org/10.3390/met11111830
SN - 2075-4701
VL - 11
IS - 11
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Wendt, Martin
A1 - Bouche, Nicolas F.
A1 - Zabl, Johannes
A1 - Schroetter, Ilane
A1 - Muzahid, Sowgat
T1 - MusE GAs FLOw and Wind V. The dust/metallicity-anisotropy of the circum-galactic medium
JF - Monthly notices of the Royal Astronomical Society
N2 - We investigate whether the dust content of the circum-galactic medium (CGM) depends on the location of the quasar sightline with respect to the galaxy major-axis using 13 galaxy-Mg II absorber pairs (9-81 kpc distance) from the MusE GAs FLOw and Wind (MEGAFLOW) survey at 0.4 < z < 1.4. The dust content of the CGM is obtained from [Zn/Fe] using ultraviolet and visual echelle spectrograph data. When a direct measurement of [Zn/Fe] is unavailable, we estimate the dust depletion from a method that consists in solving for the depletion from multiple singly ionized ions (e.g. Mn II, Cr II, and Zn II) since each ion depletes on dust grains at different rates. We find a positive correlation between the azimuthal angle and [Zn/Fe] with a Pearson's gamma = 0.70 +/- 0.14. The sightlines along the major axis show [Zn/Fe] < 0.5, whereas the [Zn/Fe] is > 0.8 along the minor axis. These results suggest that the CGM along the minor axis is on average more metal enriched (by approximate to 1 dex) than the gas located along the major axis of galaxies provided that dust depletion is a proxy for metallicity. This anisotropic distribution is consistent with recent results on outflow and accretion in hydro-dynamical simulations.
KW - galaxies: evolution
KW - galaxies: formation
KW - intergalactic medium
KW - quasars:
KW - absorption lines
Y1 - 2021
U6 - https://doi.org/10.1093/mnras/stab049
SN - 0035-8711
SN - 1365-2966
VL - 502
IS - 3
SP - 3733
EP - 3745
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Hawro, Tomasz
A1 - Przybylowicz, Katarzyna
A1 - Spindler, Max
A1 - Hawro, Marlena
A1 - Steć, Michał
A1 - Altrichter, Sabine
A1 - Weller, Karsten
A1 - Magerl, Markus
A1 - Reidel, Ulrich
A1 - Alarbeed, Ezzat
A1 - Alraboni, Ola
A1 - Maurer, Marcus
A1 - Metz, Martin
T1 - The characteristics and impact of pruritus in adult dermatology patients
BT - a prospective, cross-sectional study
JF - Journal of the American Academy of Dermatology
N2 - Background:
Pruritus often accompanies chronic skin diseases, exerting considerable burden on many areas of patient functioning; this burden and the features of pruritus remain insufficiently characterized.
Objective:
To investigate characteristics, including localization patterns, and burden of pruritus in patients with chronic dermatoses.
Methods:
We recruited 800 patients with active chronic skin diseases. We assessed pruritus intensity, localization, and further characteristics. We used validated questionnaires to assess quality of life, work productivity and activity impairment, anxiety, depression, and sleep quality.
Results:
Nine out of every 10 patients had experienced pruritus throughout their disease and 73% in the last 7 days. Pruritus often affected the entire body and was not restricted to skin lesions. Patients with moderate to severe pruritus reported significantly more impairment to their sleep quality and work productivity, and they were more depressed and anxious than control individuals and patients with mild or no pruritus. Suicidal ideations were highly prevalent in patients with chronic pruritus (18.5%) and atopic dermatitis (11.8%).
Conclusions:
Pruritus prevalence and intensity are very high across all dermatoses studied; intensity is linked to impairment in many areas of daily functioning. Effective treatment strategies are urgently required to treat pruritus and the underlying skin disease. ( J Am Acad Dermatol 2021;84:691-700.)
KW - activity
KW - anxiety
KW - depression
KW - pruritus
KW - quality of life
KW - sleep quality
KW - suicidal ideations
KW - work productivity
Y1 - 2021
U6 - https://doi.org/10.1016/J.JAAD.2020.08.035
SN - 0190-9622
SN - 1097-6787
VL - 84
IS - 3
SP - 691
EP - 700
PB - Elsevier
CY - Amsterdam [u.a.]
ER -
TY - JOUR
A1 - Scheffler, Christiane
A1 - Hermanussen, Michael
A1 - Rogol, Alan D.
T1 - Stunting
BT - historical lessons that catch-up growth tells us for mapping growth restoration
JF - Archives of disease in childhood : a peer review journal for health professionals and researchers covering conception to adolescence
Y1 - 2020
U6 - https://doi.org/10.1136/archdischild-2020-319240
SN - 0003-9888
SN - 1468-2044
VL - 106
IS - 8
SP - 819
EP - 820
PB - BMJ Publishing Group
CY - London
ER -
TY - JOUR
A1 - Kempton, Mark
A1 - Münch, Florentin
A1 - Yau, Shing-Tung
T1 - A homology vanishing theorem for graphs with positive curvature
JF - Communications in analysis and geometry
N2 - We prove a homology vanishing theorem for graphs with positive Bakry-' Emery curvature, analogous to a classic result of Bochner on manifolds [3]. Specifically, we prove that if a graph has positive curvature at every vertex, then its first homology group is trivial, where the notion of homology that we use for graphs is the path homology developed by Grigor'yan, Lin, Muranov, and Yau [11]. We moreover prove that the fundamental group is finite for graphs with positive Bakry-' Emery curvature, analogous to a classic result of Myers on manifolds [22]. The proofs draw on several separate areas of graph theory, including graph coverings, gain graphs, and cycle spaces, in addition to the Bakry-Emery curvature, path homology, and graph homotopy. The main results follow as a consequence of several different relationships developed among these different areas. Specifically, we show that a graph with positive curvature cannot have a non-trivial infinite cover preserving 3-cycles and 4-cycles, and give a combinatorial interpretation of the first path homology in terms of the cycle space of a graph. Furthermore, we relate gain graphs to graph homotopy and the fundamental group developed by Grigor'yan, Lin, Muranov, and Yau [12], and obtain an alternative proof of their result that the abelianization of the fundamental group of a graph is isomorphic to the first path homology over the integers.
Y1 - 2021
UR - https://www.intlpress.com/site/pub/files/_fulltext/journals/cag/2021/0029/0006/CAG-2021-0029-0006-a005.pdf
U6 - https://doi.org/10.4310/CAG.2021.v29.n6.a5
SN - 1019-8385
SN - 1944-9992
VL - 29
IS - 6
SP - 1449
EP - 1473
PB - International Press of Boston
CY - Somerville
ER -
TY - JOUR
A1 - Fruhstorfer, Anna
T1 - Constitutional revolutions under autocracy
JF - Constitutional studies
N2 - Gary Jacobsohn and Yaniv Roznai’s (2020) book Constitutional Revolution offers a sophisticated conceptual framework with a fascinating description of empirical occurrences of substantive revolutions in the practice and understanding of constitutionalism in Germany, India, Hungary, and Israel. While the conceptualization in the book and its empirical illustration clearly draw from regime transformations or substantive changes within democratic regimes, we know little about the extent to which substantive constitutional reforms are possible and meaningful in autocratic regimes. As their concept of constitutional revolution is ambiguous and requires a substantive engagement with an individual case at hand, we cannot sim- ply expect concept equivalence when expanding its use beyond a transitory or democratic context. Hence, in this contribution I ask, What constitutes a constitutional revolution in an autocratic regime? To shed light on this question, I rely on the expectation that we do not find important differences in the substance of autocratic constitutions compared to democratic constitutions. Autocratic elites, also, under- stand the possibilities of constitutional change and respond to them as they offer regime stability and simply more power, but that is not a revolution. Therefore, I argue that the substantive meaning of an amendment must be a departure from the inherent logic of the constitution, especially outside the standard procedures for autocratic ruling. Thus, in this paper I discuss the theoretical implications of a constitutional revolution under autocracy without a regime transition and provide empirical evidence from various constitutional amendments and de facto reforms in Russia. I show that a constitutional revolution is not always the most important or most discussed constitutional change—at least, not in an autocratic context. This discussion has important implications for understanding constitutionalism and autocratic stability and the largely overlooked relationship between substance and process in nondemocratic settings.
KW - constitutional revolution
KW - Russia
KW - federalism
KW - autocracy
Y1 - 2021
UR - https://constitutionalstudies.wisc.edu/index.php/cs/article/view/69
SN - 2474-9427
SN - 2474-9419
VL - 7
IS - 1
SP - 33
EP - 47
PB - University of Wisconsin Press
CY - Madison
ER -
TY - JOUR
A1 - Lass, Sander
A1 - Abendroth, Adrian
A1 - Theuer, Hanna Katharina
T1 - Marktübersicht IIoT-Plattformen
JF - Fabriksoftware : die digitale Fabrik realisieren
N2 - Das Industrial Internet of Things (IIoT) verbindet Sensoren, Maschinen und andere mit Computern vernetzte Geräte für industrielle Anwendungen. Durch die Nutzung von IIoT-Plattformen in Produktion und Logistik können Unternehmen ihre Daten systematisch und aggregiert bereitstellen und fördern so eine schnelle und unternehmensübergreifende Kommunikation. Die Potenziale - u. a. innovative Produkte, neue Dienstleistungen und Geschäftsmodelle sowie effizientere betriebliche Prozesse [1]- von cyber-physischen Systemen können auf diese Weise entlang der gesamten Wertschöpfungskette gehoben werden [2].
Y1 - 2021
UR - https://www.wiso-net.de/document/PPS__375886627fc4e72e6cad8deba2de048e1b3cb45b
SN - 2569-7692
VL - 26
IS - 1
SP - 54
EP - 63
PB - GITO mbH
CY - Berlin
ER -
TY - JOUR
A1 - Sandhage-Hofmann, Alexandra
A1 - Linstädter, Anja
A1 - Kindermann, Liana
A1 - Angombe, Simon
A1 - Amelung, Wulf
T1 - Conservation with elevated elephant densities sequesters carbon in soils despite losses of woody biomass
JF - Global change biology
N2 - Nature conservation and restoration in terrestrial ecosystems is often focused on increasing the numbers of megafauna, expecting them to have positive impacts on ecological self-regulation processes and biodiversity. In sub-Saharan Africa, conservation efforts also aspire to protect and enhance biodiversity with particular focus on elephants. However, elephant browsing carries the risk of woody biomass losses. In this context, little is known about how increasing elephant numbers affects carbon stocks in soils, including the subsoils. We hypothesized that (1) increasing numbers of elephants reduce tree biomass, and thus the amount of C stored therein, resulting (2) in a loss of soil organic carbon (SOC). If true, a negative carbon footprint could limit the sustainability of elephant conservation from a global carbon perspective. To test these hypotheses, we selected plots of low, medium, and high elephant densities in two national parks and adjacent conservancies in the Namibian component of the Kavango Zambezi Transfrontier Area (KAZA), and quantified carbon storage in both woody vegetation and soils (1 m). Analyses were supplemented by the assessment of soil carbon isotopic composition. We found that increasing elephant densities resulted in a loss of tree carbon storage by 6.4 t ha(-1). However, and in contrast to our second hypothesis, SOC stocks increased by 4.7 t ha(-1) with increasing elephant densities. These higher SOC stocks were mainly found in the topsoil (0-30 cm) and were largely due to the formation of SOC from woody biomass. A second carbon input source into the soils was megaherbivore dung, which contributed with 0.02-0.323 t C ha(-1) year(-1) to ecosystem carbon storage in the low and high elephant density plots, respectively. Consequently, increasing elephant density does not necessarily lead to a negative C footprint, as soil carbon sequestration and transient C storage in dung almost compensate for losses in tree biomass.
KW - carbon sequestration
KW - conservation
KW - elephants
KW - soil organic carbon
KW - woody biomass
Y1 - 2021
U6 - https://doi.org/10.1111/gcb.15779
SN - 1354-1013
SN - 1365-2486
VL - 27
IS - 19
SP - 4601
EP - 4614
PB - Blackwell Science
CY - Oxford [u.a.]
ER -
TY - JOUR
A1 - Steding, Svenja
A1 - Schneider, Wilfried
T1 - Prognose des Schadstoffaustrags aus mehrphasigen DNAPL-Pools mittels semi-analytischem Berechnungsmodell
JF - Grundwasser : Zeitschrift der Fachsektion Hydrogeologie in der Deutschen Gesellschaft für Geowissenschaften (FH-DGG)
N2 - Multicomponent DNAPL pools are among the most common reasons for groundwater contamination and represent highly persistent source areas. Although several studies have already shown that their constituents influence each other's solubility, existing models neglect these interactions. For this reason, a semi-analytical model has been developed, considering the pool composition as temporally variable. Based on Raoult's law, the molar fraction, the effective solubility and finally the mass discharge due to advection, dispersion and diffusion of each component are determined. The results significantly differ from studies on single-phase pools. It is shown that mass discharges can both increase and decrease over time and that the longevity of DNAPL pools as well as the time until threshold values are fullfilled will be significantly underestimated if Raoult's law is neglected. Additionally, a sensitivity analysis reveals that poorly soluble minor components must not be neglected, whereas highly soluble ones can.
N2 - Mehrphasige DNAPL-Pools zählen zu den häufigsten Ursachen für Grundwasserkontaminationen und sind bekannt für ihre Langlebigkeit. Obwohl Untersuchungen bereits gezeigt haben, dass die Phasen sich in ihrer Wasserlöslichkeit gegenseitig beeinflussen, werden diese Interaktionen von bisherigen Modellen vernachlässigt. Aus diesem Grund wurde ein semi-analytisches Berechnungsmodell entwickelt, welches die Poolzusammensetzung als zeitlich variabel behandelt. Basierend auf dem Raoult’schen Gesetz werden für jede Komponente Molanteil, effektive Wasserlöslichkeit und schließlich der Schadstoffaustrag infolge Advektion, Dispersion und Diffusion bestimmt. Die Ergebnisse unterscheiden sich deutlich von Studien an einphasigen Pools. So wird gezeigt, dass Schadstofffrachten über die Zeit sowohl zu- als auch abnehmen können und dass ohne Berücksichtigung des Raoult’schen Gesetzes sowohl die Langlebigkeit von DNAPL-Pools als auch die Dauer bis zur Unterschreitung von Grenzwerten teils deutlich unterschätzt wird. Eine Sensitivitätsanalyse zeigt zudem, dass schwer lösliche Nebenbestandteile nicht vernachlässigt werden dürfen, leicht lösliche hingegen schon.
T2 - Prediction of mass discharge from multicomponent DNAPL pools using a semi-analytical model
KW - Contamination
KW - Source longevity
KW - Raoult's law
KW - Matrix diffusion
KW - Minor
KW - components
Y1 - 2021
U6 - https://doi.org/10.1007/s00767-021-00490-2
SN - 1430-483X
SN - 1432-1165
VL - 26
IS - 3
SP - 241
EP - 253
PB - Springer
CY - Berlin ; Heidelberg
ER -
TY - JOUR
A1 - Cherstvy, Andrey G.
A1 - Vinod, Deepak
A1 - Aghion, Erez
A1 - Sokolov, Igor M.
A1 - Metzler, Ralf
T1 - Scaled geometric Brownian motion features sub- or superexponential ensemble-averaged, but linear time-averaged mean-squared displacements
JF - Physical review : E, Statistical, nonlinear and soft matter physics
N2 - Various mathematical Black-Scholes-Merton-like models of option pricing employ the paradigmatic stochastic process of geometric Brownian motion (GBM). The innate property of such models and of real stock-market prices is the roughly exponential growth of prices with time [on average, in crisis-free times]. We here explore the ensemble- and time averages of a multiplicative-noise stochastic process with power-law-like time-dependent volatility, sigma(t) similar to t(alpha), named scaled GBM (SGBM). For SGBM, the mean-squared displacement (MSD) computed for an ensemble of statistically equivalent trajectories can grow faster than exponentially in time, while the time-averaged MSD (TAMSD)-based on a sliding-window averaging along a single trajectory-is always linear at short lag times Delta. The proportionality factor between these the two averages of the time series is Delta/T at short lag times, where T is the trajectory length, similarly to GBM. This discrepancy of the scaling relations and pronounced nonequivalence of the MSD and TAMSD at Delta/T << 1 is a manifestation of weak ergodicity breaking for standard GBM and for SGBM with s (t)-modulation, the main focus of our analysis. The analytical predictions for the MSD and mean TAMSD for SGBM are in quantitative agreement with the results of stochastic computer simulations.
Y1 - 2021
U6 - https://doi.org/10.1103/PhysRevE.103.062127
SN - 2470-0045
SN - 2470-0053
VL - 103
IS - 6
PB - American Physical Society
CY - College Park
ER -
TY - JOUR
A1 - Worseck, Gábor
A1 - Khrykin, Ilya Sergeevich
A1 - Hennawi, Joseph F.
A1 - Prochaska, J. Xavier
A1 - Farina, Emanuele Paolo
T1 - Dating individual quasars with the He II proximity effect
JF - Monthly notices of the Royal Astronomical Society
N2 - Constraints on the time-scales of quasar activity are key to understanding the formation and growth of supermassive black holes (SMBHs), quasar triggering mechanisms, and possible feedback effects on their host galaxies. However, observational estimates of this so-called quasar lifetime are highly uncertain (t(Q) similar to 10(4)-10(9) yr), because most methods are indirect and involve many model-dependent assumptions. Direct evidence of earlier activity is gained from the higher ionization state of the intergalactic medium (IGM) in the quasar environs, observable as enhanced Ly alpha transmission in the so-called proximity zone. Due to the similar to 30 Myr equilibration time-scale of He II in the z similar to 3 IGM, the size of the He II proximity zone depends on the time the quasar had been active before our observation t(on) <= t(Q), enabling up to +/- 0.2 dex precise measurements of individual quasar on-times that are comparable to the e-folding time-scale t(S) <= 44 Myr of SMBH growth. Here we present the first statistical sample of 13 quasars whose accurate and precise systemic redshifts allow for measurements of sufficiently precise He II quasar proximity zone sizes between similar or equal to 2 and similar or equal to 15 proper Mpc from science-grade Hubble Space Telescope (HST) spectra. Comparing these sizes to predictions from cosmological hydrodynamical simulations post-processed with 1D radiative transfer, we infer a broad range of quasar on-times from t(on) less than or similar to 1Myr to t(on) > 30 Myr that does not depend on quasar luminosity, black hole mass, or Eddington ratio. These results point to episodic quasar activity over a long duty cycle, but do not rule out substantial SMBH growth during phases of radiative inefficiency or obscuration.
KW - intergalactic medium
KW - quasars: absorption lines
KW - quasars: general
KW - quasars: supermassive black holes
KW - dark ages, reionization, first stars
Y1 - 2021
U6 - https://doi.org/10.1093/mnras/stab1685
SN - 0035-8711
SN - 1365-2966
VL - 505
IS - 4
SP - 5084
EP - 5103
PB - Oxford Univ. Press
CY - Oxford
ER -
TY - JOUR
A1 - Balderjahn, Ingo
A1 - Seegebarth, Barbara
A1 - Lee, Michael S. W.
T1 - Less is more!
BT - The rationale behind the decision-making style of voluntary simplifiers
JF - Journal of cleaner production
N2 - Enhancing consumer satisfaction and well-being is an important objective of companies, retailers and public policy makers. In the current debate on climate change, a consistent theme is that consumers in developed countries must learn to consume less. The present study (based on representative data sets from the US, N = 1,017, and Germany, N = 1030) addresses these issues by using a scenario-based experiment to analyze how satisfied voluntary simplifiers (people who voluntarily abstain from consumption) are with their purchase decisions in the case of a muesli brand. The research question is whether people who follow a sustainable, simple lifestyle are more satisfied with their daily consumption choices than people who have a more consumerist lifestyle. If so, it would be easier for many people to change their lifestyles and consume less. In addition, this scenario experiment manipulates consumer empowerment and decision complexity since both factors are supposed to influence purchase satisfaction. The results are consistent across both countries and indicate that voluntary simplifiers experience a higher level of purchasing satisfaction than non-simplifiers, whereby empowerment and decision complexity play different roles.
KW - voluntarily simplicity
KW - well-being
KW - consumer empowerment
KW - decision complexity
KW - sustainable consumption
Y1 - 2020
U6 - https://doi.org/10.1016/j.jclepro.2020.124802
SN - 0959-6526
SN - 1879-1786
VL - 284
PB - Elsevier Science
CY - Amsterdam
ER -
TY - JOUR
A1 - Franović, Igor
A1 - Omel'chenko, Oleh
A1 - Wolfrum, Matthias
T1 - Bumps, chimera states, and Turing patterns in systems of coupled active rotators
JF - Physical review : E, Statistical, nonlinear and soft matter physics
N2 - Self-organized coherence-incoherence patterns, called chimera states, have first been reported in systems of Kuramoto oscillators. For coupled excitable units, similar patterns where coherent units are at rest are called bump states. Here, we study bumps in an array of active rotators coupled by nonlocal attraction and global repulsion. We demonstrate how they can emerge in a supercritical scenario from completely coherent Turing patterns: a single incoherent unit appears in a homoclinic bifurcation, undergoing subsequent transitions to quasiperiodic and chaotic behavior, which eventually transforms into extensive chaos with many incoherent units. We present different types of transitions and explain the formation of coherence-incoherence patterns according to the classical paradigm of short-range activation and long-range inhibition.
Y1 - 2021
U6 - https://doi.org/10.1103/PhysRevE.104.L052201
SN - 2470-0045
SN - 2470-0053
VL - 104
IS - 5
PB - American Physical Society
CY - College Park
ER -
TY - JOUR
A1 - Ihlenburg, Ramona
A1 - Mai, Tobias
A1 - Thünemann, Andreas F.
A1 - Baerenwald, Ruth
A1 - Saalwächter, Kay
A1 - Koetz, Joachim
A1 - Taubert, Andreas
T1 - Sulfobetaine hydrogels with a complex multilength-scale hierarchical structure
JF - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical chemistry
N2 - Hydrogels with a hierarchical structure were prepared from a new highly water-soluble crosslinker N,N,N',N'-tetramethyl-N,N'-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and from the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The free radical polymerization of the two compounds is rapid and yields near-transparent hydrogels with sizes up to 5 cm in diameter. Rheology shows a clear correlation between the monomer-to-crosslinker ratio and the storage and loss moduli of the hydrogels. Cryo-scanning electron microscopy, low-field nuclear magnetic resonance (NMR) spectroscopy, and small-angle X-ray scattering show that the gels have a hierarchical structure with features spanning the nanometer to the sub-millimeter scale. The NMR study is challenged by the marked inhomogeneity of the gels and the complex chemical structure of the sulfobetaine monomer. NMR spectroscopy shows how these complications can be addressed via a novel fitting approach that considers the mobility gradient along the side chain of methacrylate-based monomers.
KW - Defects
KW - Hydrogels
KW - Nuclear magnetic resonance spectroscopy
KW - Scattering
KW - X-ray scattering
Y1 - 2021
U6 - https://doi.org/10.1021/acs.jpcb.0c10601
SN - 1520-6106
SN - 1520-5207
VL - 125
IS - 13
SP - 3398
EP - 3408
PB - American Chemical Society
CY - Washington
ER -
TY - JOUR
A1 - Binder, Beate
A1 - Apelt, Maja
T1 - Legal Gender Studies: Herausforderungen und Perspektiven feministischer Rechtskritik
BT - Beate Binder und Maja Apelt im Gespräch mit Elisabeth Holzleithner
JF - Feministische Studien
Y1 - 2021
U6 - https://doi.org/10.1515/fs-2021-0034
SN - 0723-5186
SN - 2365-9920
VL - 39
IS - 2
SP - 321
EP - 340
PB - De Gruyter Oldenbourg
CY - Berlin
ER -
TY - JOUR
A1 - Deb, Marwan
A1 - Molho, Pierre
A1 - Barbara, Bernard
T1 - Tunable exchange-bias-like effect in bi-substituted Gadolinium iron garnet film
JF - Physical review applied
N2 - Using magneto-optical Faraday and Kerr measurements, we investigate the magnetic and magnetooptical properties of a thick Bi-substituted gadolinium iron garnet film over a broad range of wavelengths (250-850 nm) and temperatures (150-300 K), including the magnetization compensation point, TM. We observe an exchange-bias-like effect in the vicinity of TM. By slightly changing the sample temperature, we can precisely tune the bias field, which reaches a magnitude 6 times higher than the coercive field. We explain this phenomenon by considering the short-range superexchange interaction and a change in the magnetic behavior when moving from the surface to the bulk of the film. This finding may lead to the development of single-film magneto-optical devices based on the exchange-bias effect.
Y1 - 2021
U6 - https://doi.org/10.1103/PhysRevApplied.15.054064
SN - 2331-7019
VL - 15
IS - 5
PB - American Physical Society
CY - College Park
ER -
TY - JOUR
A1 - Dörries, Timo
A1 - Loos, Sarah Anna Marie
A1 - Klapp, Sabine H. L.
T1 - Correlation functions of non-Markovian systems out of equilibrium
BT - analytical expressions beyond single-exponential memory
JF - Journal of statistical mechanics: theory and experiment : JSTAT
N2 - This paper is concerned with correlation functions of stochastic systems with memory, a prominent example being a molecule or colloid moving through a complex (e.g. viscoelastic) fluid environment. Analytical investigations of such systems based on non-Markovian stochastic equations are notoriously difficult. A common approximation is that of a single-exponential memory, corresponding to the introduction of one auxiliary variable coupled to the Markovian dynamics of the main variable. As a generalization, we here investigate a class of 'toy' models with altogether three degrees of freedom, giving rise to more complex forms of memory. Specifically, we consider, mainly on an analytical basis, the under- and overdamped motion of a colloidal particle coupled linearly to two auxiliary variables, where the coupling between variables can be either reciprocal or non-reciprocal. Projecting out the auxiliary variables, we obtain non-Markovian Langevin equations with friction kernels and colored noise, whose structure is similar to that of a generalized Langevin equation. For the present systems, however, the non-Markovian equations may violate the fluctuation-dissipation relation as well as detailed balance, indicating that the systems are out of equilibrium. We then study systematically the connection between the coupling topology of the underlying Markovian system and various autocorrelation functions. We demonstrate that already two auxiliary variables can generate surprisingly complex (e.g. non-monotonic or oscillatory) memory and correlation functions. Finally, we show that a minimal overdamped model with two auxiliary variables and suitable non-reciprocal coupling yields correlation functions resembling those describing hydrodynamic backflow in an optical trap.
KW - correlation functions
KW - memory effects
KW - friction
Y1 - 2021
U6 - https://doi.org/10.1088/1742-5468/abdead
SN - 1742-5468
IS - 3
PB - IOP Publ. Ltd.
CY - Bristol
ER -