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On the basis of certain semantic intuitions, Barros (2012) argues that ellipsis does not require structural isomorphism between elided structure and its antecedent. We tackle this claim. Semantic intuitions cannot be a pointer to the analysis of silent structure. We provide empirical evidence that raises the question of to what extent semantic intuitions about plausible articulable syntax must inform one's analysis of silent structure. We conclude that the answer to this question must be crosslinguistically informed. We conjecture that ellipsis introduces ellipsis-specific interpretive mechanisms, so that intuitions about "how the unelided structure would be interpreted" are not empirically relevant.
Spreadsheets are among the most commonly used file formats for data management, distribution, and analysis. Their widespread employment makes it easy to gather large collections of data, but their flexible canvas-based structure makes automated analysis difficult without heavy preparation. One of the common problems that practitioners face is the presence of multiple, independent regions in a single spreadsheet, possibly separated by repeated empty cells. We define such files as "multiregion" files. In collections of various spreadsheets, we can observe that some share the same layout. We present the Mondrian approach to automatically identify layout templates across multiple files and systematically extract the corresponding regions. Our approach is composed of three phases: first, each file is rendered as an image and inspected for elements that could form regions; then, using a clustering algorithm, the identified elements are grouped to form regions; finally, every file layout is represented as a graph and compared with others to find layout templates. We compare our method to state-of-the-art table recognition algorithms on two corpora of real-world enterprise spreadsheets. Our approach shows the best performances in detecting reliable region boundaries within each file and can correctly identify recurring layouts across files.
Dem Mitarbeiter zu Diensten
(2021)
Die Weiterbildung und Qualifizierung der Mitarbeiter sind zentrale Erfolgsfaktoren des digitalen Wandels. Die zentrale Herausforderung besteht darin, diese maßgeschnitten anzubieten sowie notwendige Akzeptanz nicht vorauszusetzen, sondern ebenso als Zielgröße anzusehen. Dies geschieht jedoch nur, wenn die Mitarbeiter als Partner gesehen werden, deren Bedürfnisse und Verständnis nachhaltig berücksichtigt werden. Dieser Beitrag schlägt vor diesem Hintergrund einen Ansatz vor, Weiterbildung als Personennahe Dienstleistung zu realisieren. Dafür wird zuerst ein skizzenhafter Überblick über grundlegende Kompetenzanforderungen des digitalen Wandels gegeben. Danach wird die aktuelle Situation betrieblicher Weiterbildung in der digitalen Transformation beleuchtet. Hierzu wurde in einem Zeitraum von sechs Monaten im Rahmen einer quantitativen Untersuchung erhoben, wie Beschäftigte die digitale Transformation ihres Unternehmens und daraus resultierende Bedarfe betrieblicher Weiterbildung wahrnehmen. Darauf basierend werden drei aktuelle Paradoxe abgeleitet, die mit einer Durchführung von Weiterbildung als Personennahe Dienstleistung verhindert werden können. Empfehlungen und Lösungsansätze werden hierzu diskutiert und weiterer Forschungsbedarf abgeleitet.
The design of qualitative, excellent teaching requires collaboration between teachers and learners. For this purpose, face-to-face teaching benefits from a long-standing tradition, while digital teaching is comparatively still at the beginning of its dissemination. A major developmental step toward the digitization of teaching was achieved in the context of university teaching during the Covid 19 pandemic in spring 2020, when face-to-face teaching was interrupted for months. During this time, important insights into the opportunities and limitations of digital teaching were gained. This paper presents selected results of a study conducted at four German universities and with 875 responses in spring 2020. The study uncovers opportunities and limitations of digital teaching from the students’ perspective and against the background of their experience in the completely digital semester. The results are used as a basis for deriving design guidelines for digital teaching and learning offerings. Based on a model for analyzing the design of teaching and learning formats, these indications are structured according to the elements learners, teachers, teaching content, environment and teaching style.
Yes, we can (?)
(2021)
The COVID-19 crisis has caused an extreme situation for higher education institutions around the world, where exclusively virtual teaching and learning has become obligatory rather than an additional supporting feature. This has created opportunities to explore the potential and limitations of virtual learning formats. This paper presents four theses on virtual classroom teaching and learning that are discussed critically. We use existing theoretical insights extended by empirical evidence from a survey of more than 850 students on acceptance, expectations, and attitudes regarding the positive and negative aspects of virtual teaching. The survey responses were gathered from students at different universities during the first completely digital semester (Spring-Summer 2020) in Germany. We discuss similarities and differences between the subjects being studied and highlight the advantages and disadvantages of virtual teaching and learning. Against the background of existing theory and the gathered data, we emphasize the importance of social interaction, the combination of different learning formats, and thus context-sensitive hybrid learning as the learning form of the future.
In response to the impending spread of COVID-19, universities worldwide abruptly stopped face-to-face teaching and switched to technology-mediated teaching. As a result, the use of technology in the learning processes of students of different disciplines became essential and the only way to teach, communicate and collaborate for months. In this crisis context, we conducted a longitudinal study in four German universities, in which we collected a total of 875 responses from students of information systems and music and arts at four points in time during the spring–summer 2020 semester. Our study focused on (1) the students’ acceptance of technology-mediated learning, (2) any change in this acceptance during the semester and (3) the differences in acceptance between the two disciplines. We applied the Technology Acceptance Model and were able to validate it for the extreme situation of the COVID-19 pandemic. We extended the model with three new variables (time flexibility, learning flexibility and social isolation) that influenced the construct of perceived usefulness. Furthermore, we detected differences between the disciplines and over time. In this paper, we present and discuss our study’s results and derive short- and long-term implications for science and practice.
By using mouse outcross populations in combination with bioinformatic approaches, it was possible to identify and characterize novel genes regulating body weight, fat mass and β-cell function, which all contribute to the pathogenesis of obesity and T2D. In detail, the presented studies identified 1. Ifi202b/IFI16 as adipogenic gene involved in adipocyte commitment, maintenance of white adipocyte identity, fat cell size and the inflammatory state of adipose tissue. 2. Pla2g4a/PLA2G4A as gene linked to increased body weight and fat mass with a higher expression in adipose tissue of obese mice and pigs as well as in obese human subjects. 3. Ifgga2/IRGM as novel regulator of lipophagy protecting from excess hepatic lipid accumulation. 4. Nidd/DBA as a diabetogenic locus containing Kti12, Osbpl9, Ttc39a and Calr4 with differential expression in pancreatic islets and/or genetic variants. 5. miR-31 to be higher expressed in adipose tissue of obese and diabetic mice and humans targeting PPARy and GLUT4 and thereby involved in adipogenesis and insulin signaling. 6. Gjb4 as novel gene triggering the development of T2D by reducing insulin secretion, inducing apoptosis and inhibiting proliferation. The performed studies confirmed the complexity and strong genetic heritability character of obesity and T2D. A high number of genetic variations, each with a small effect, are collectively influencing the degree and severity of the disease. The use of mouse outcross populations is a valid tool for disease gene identification; however, to facilitate and accelerate the process of gene identification the combination of mouse cross data with advanced sequencing resources and the publicly available data sets are essential. The main goal for future studies should be the translation of these novel molecular discoveries to useful treatment therapies. More recently, several classes of novel unimolecular combination therapeutics have emerged with superior efficacy than currently prescribed options and pose the potential to reverse obesity and T2D (Finan et al., 2015). The glucagon-like peptide-1 (GLP-1)- estrogen conjugate, which targets estrogen into cells expressing GLP-1 receptors, was shown to improve energy, glucose and lipid metabolism as well as to reduce food reward (Finan et al., 2012; Schwenk et al., 2014; Vogel et al., 2016). Another possibility is the development of miRNA-based therapeutics to prevent obesity and T2D, such as miRNA mimetics, anti-miRNA oligonucleotides and exosomes loaded with miRNAs (Ji and Guo, 2019; Gottmann et al., 2020). As already described, genome-wide association studies for polygenic obesity and T2D traits in humans have also led to the identification of numerous gene variants with modest effect, most of them having an unknown function (Yazdi et al., 2015). These discoveries resulted in novel animal models and have illuminated new biologic pathways. Therefore, the integration of mouse-human genetic approaches and the utilization of the synergistic effects have the potential to lead to the identification of more genes responsible for common Mendelian forms of obesity and T2D, as well as gene × gene and gene × environment interactions (Yazdi et al., 2015; Ingelsson and McCarthy, 2018). This combination may help to unravel the missing heritability of obesity and T2D, to identify novel drug targets and to design more efficient and personalized obesity prevention and management programs.
The co-occurrence of warm spells and droughts can lead to detrimental socio-economic and ecological impacts, largely surpassing the impacts of either warm spells or droughts alone. We quantify changes in the number of compound warm spells and droughts from 1979 to 2018 in the Mediterranean Basin using the ERA5 data set. We analyse two types of compound events: 1) warm season compound events, which are extreme in absolute terms in the warm season from May to October and 2) year-round deseasonalised compound events, which are extreme in relative terms respective to the time of the year. The number of compound events increases significantly and especially warm spells are increasing strongly – with an annual growth rates of 3.9 (3.5) % for warm season (deseasonalised) compound events and 4.6 (4.4) % for warm spells –, whereas for droughts the change is more ambiguous depending on the applied definition. Therefore, the rise in the number of compound events is primarily driven by temperature changes and not the lack of precipitation. The months July and August show the highest increases in warm season compound events, whereas the highest increases of deseasonalised compound events occur in spring and early summer. This increase in deseasonalised compound events can potentially have a significant impact on the functioning of Mediterranean ecosystems as this is the peak phase of ecosystem productivity and a vital phenophase.
Mediterranean ecosystems are particularly vulnerable to climate change and the associated increase in climate anomalies. This study investigates extreme ecosystem responses evoked by climatic drivers in the Mediterranean Basin for the time span 1999–2019 with a specific focus on seasonal variations as the seasonal timing of climatic anomalies is considered essential for impact and vulnerability assessment. A bivariate vulnerability analysis is performed for each month of the year to quantify which combinations of the drivers temperature (obtained from ERA5-Land) and soil moisture (obtained from ESA CCI and ERA5-Land) lead to extreme reductions in ecosystem productivity using the fraction of absorbed photosynthetically active radiation (FAPAR; obtained from the Copernicus Global Land Service) as a proxy.
The bivariate analysis clearly showed that, in many cases, it is not just one but a combination of both drivers that causes ecosystem vulnerability. The overall pattern shows that Mediterranean ecosystems are prone to three soil moisture regimes during the yearly cycle: they are vulnerable to hot and dry conditions from May to July, to cold and dry conditions from August to October, and to cold conditions from November to April, illustrating the shift from a soil-moisture-limited regime in summer to an energy-limited regime in winter. In late spring, a month with significant vulnerability to hot conditions only often precedes the next stage of vulnerability to both hot and dry conditions, suggesting that high temperatures lead to critically low soil moisture levels with a certain time lag. In the eastern Mediterranean, the period of vulnerability to hot and dry conditions within the year is much longer than in the western Mediterranean. Our results show that it is crucial to account for both spatial and temporal variability to adequately assess ecosystem vulnerability. The seasonal vulnerability approach presented in this study helps to provide detailed insights regarding the specific phenological stage of the year in which ecosystem vulnerability to a certain climatic condition occurs.
How to cite.
Vogel, J., Paton, E., and Aich, V.: Seasonal ecosystem vulnerability to climatic anomalies in the Mediterranean, Biogeosciences, 18, 5903–5927, https://doi.org/10.5194/bg-18-5903-2021, 2021.
Compound weather events may lead to extreme impacts that can affect many aspects of society including agriculture. Identifying the underlying mechanisms that cause extreme impacts, such as crop failure, is of crucial importance to improve their understanding and forecasting. In this study, we investigate whether key meteorological drivers of extreme impacts can be identified using the least absolute shrinkage and selection operator (LASSO) in a model environment, a method that allows for automated variable selection and is able to handle collinearity between variables. As an example of an extreme impact, we investigate crop failure using annual wheat yield as simulated by the Agricultural Production Systems sIMulator (APSIM) crop model driven by 1600 years of daily weather data from a global climate model (EC-Earth) under present-day conditions for the Northern Hemisphere. We then apply LASSO logistic regression to determine which weather conditions during the growing season lead to crop failure. We obtain good model performance in central Europe and the eastern half of the United States, while crop failure years in regions in Asia and the western half of the United States are less accurately predicted. Model performance correlates strongly with annual mean and variability of crop yields; that is, model performance is highest in regions with relatively large annual crop yield mean and variability. Overall, for nearly all grid points, the inclusion of temperature, precipitation and vapour pressure deficit is key to predict crop failure. In addition, meteorological predictors during all seasons are required for a good prediction. These results illustrate the omnipresence of compounding effects of both meteorological drivers and different periods of the growing season for creating crop failure events. Especially vapour pressure deficit and climate extreme indicators such as diurnal temperature range and the number of frost days are selected by the statistical model as relevant predictors for crop failure at most grid points, underlining their overarching relevance. We conclude that the LASSO regression model is a useful tool to automatically detect compound drivers of extreme impacts and could be applied to other weather impacts such as wildfires or floods. As the detected relationships are of purely correlative nature, more detailed analyses are required to establish the causal structure between drivers and impacts.
Non-geminate recombination, as one of the most relevant loss mechanisms in organic and perovskite solar cells, deserves special attention in research efforts to further increase device performance. It can be subdivided into first, second, and third order processes, which can be elucidated by the effects that they have on the time-dependent open-circuit voltage decay. In this study, analytical expressions for the open-circuit voltage decay exhibiting one of the aforementioned recombination mechanisms were derived. It was possible to support the analytical models with experimental examples of three different solar cells, each of them dominated either by first (PBDBT:CETIC-4F), second (PM6:Y6), or third (irradiated CH3NH3PbI3) order recombination. Furthermore, a simple approach to estimate the dominant recombination process was also introduced and tested on these examples. Moreover, limitations of the analytical models and the measurement technique itself were discussed.
Philosophie der Personalität
(2021)
Die Philosophie der Person tritt mit dem Anspruch an, unser Selbstverständnis als Individuen artikulieren zu wollen. Wird die gängige Lesart von Personen als rationalen, selbstbewussten Individuen diesem Anspruch wirklich gerecht? In Auseinandersetzung mit unterschiedlichen Ansätzen der Gegenwart arbeitet Moritz von Kalckreuth neben der rationalen auch die leibliche, emotionale und soziokulturelle Dimension von Personalität heraus und fragt nach der Möglichkeit, sie alle in einem „Syntheseversuch“ zusammenzuführen. Im Anschluss an Helmuth Plessners Philosophische Anthropologie, Nicolai Hartmanns Neue Ontologie und Max Schelers Phänomenologie lassen sich verschiedene Lesarten von Geist gewinnen, die sich für eine solche Verknüpfung der einzelnen Dimensionen von Personalität besonders eignen.
Die Digitalisierung unseres Lebens löst die Grenzen zwischen Privat- und Berufsleben immer weiter auf. Bekanntes Beispiel ist das Homeoffice. Arbeitgeber begegnen aber auch zahlreichen weiteren Trends in diesem Zusammenhang. Dazu gehören „workation“, also die Verbindung zwischen Arbeit („work“) und Urlaub („vacation“) ebenso wie „bleisure“, dh die Verbindung von Dienstreisen („business“) und Urlaub („leisure“). Der Beitrag geht den rechtlichen Rahmenbedingungen hierfür nach.
Trotz erfolgreicher Impfkampagne droht nach dem Sommer eine vierte Infektionswelle der Corona-Pandemie. Ob es dazu kommen wird, hängt maßgeblich davon ab, wie viele Menschen sich für eine Corona-Schutzimpfung entscheiden. Am Impfstoff mangelt es nicht mehr, dafür an der Impfbereitschaft. Viele Arbeitgeber fragen sich daher, was sie unternehmen können, um die Impfquote in ihren Betrieben zu erhöhen.
Der nach wie vor dichte Nebel der Corona-Pandemie lässt den Austritt des Vereinigten Königreichs aus der Europäischen Union („Brexit“) immer noch ein wenig aus dem Blickfeld geraten. Seine (zumeist negativen) wirtschaftlichen Auswirkungen – allein die deutschen Exporte nach Großbritannien sollen im Januar 2021 im Vergleich zum Vorjahresmonat aufgrund des zum 1.1.2021 erfolgten endgültigen Vollzugs des Brexits um rund 30 % gesunken sein (https://www.handelsblatt.com/politik/international/brexit-folgen-das-sind-die-brexit-folgen-fuer-grossbritannien-deutschland-und-die-eu/24129260.html) – bleiben daher zu sehr im Hintergrund. Dabei hat der endgültige Austritt des Vereinigten Königreichs aus der EU gerade für das Arbeitsrecht ganz erhebliche Konsequenzen.
Der Brexit ist Realität geworden. Als das Vereinigte Königreich am 31.1.2020 um Mitternacht aus der EU ausgetreten ist, begann der Übergangszeitraum, auf den man sich im Austrittsabkommen geeinigt hatte. Während dieses Zeitraums galt das Unionsrecht in der justiziellen Zusammenarbeit in Zivilsachen im Verhältnis zum und im Vereinigten Königreich fort. Der Übergangszeitraum endete am 31.12.2020. Die folgende Abhandlung beschreibt die Rechtslage in der justiziellen Zusammenarbeit in Zivilsachen vom 1.1.2021 an.
Nachtrag: Als der Beitrag geschrieben wurde, war noch offen, ob es zwischen der EU und dem Vereinigten Königreich zu einem Handels- und Kooperationsübereinkommen kommen würde. Mittlerweile liegt das entsprechende Handels- und Kooperationsabkommen vom 24.12.2020 vor. Es ist nach den Beschlüssen der zuständigen Gremien seit dem 1.1.2021 für einen begrenzten Zeitraum vorläufig und ab seinem regulären Inkrafttreten dauerhaft anzuwenden. Es enthält keine zusätzlichen Regelungen für die justizielle Zusammenarbeit in Zivilsachen zwischen dem Vereinigten Königreich und der Europäischen Union. Daraus ist zu schließen, dass der vorliegende Beitrag den mit dem Handels- und Kooperationsabkommen geschaffenen aktuellen Rechtsstand wiedergibt (Rolf Wagner).
Dingliche Arreste dürfen nach § 929 II ZPO nur innerhalb einer Frist von einem Monat vollzogen werden. Ergeht der Arrestbefehl nach mündlicher Verhandlung durch Endurteil, beginnt die Frist mit der Verkündung des Arrestbefehls. Wird ohne mündliche Verhandlung durch Beschluss entschieden, wird die Einmonatsfrist mit der Zustellung der Arrestentscheidung an den Antragsteller in Gang gesetzt. Zum 1. 1. 2022 wird § 929 II ZPO um einen zweiten Satz erweitert werden. Soll „ein ausländischer Sicherungstitel im Inland ohne vorherige Vollstreckbarerklärung“ vollzogen werden, so beträgt die Vollziehungsfrist nach dieser Regelung dann nicht nur einen Monat, sondern zwei Monate. Der folgende Beitrag geht der Frage nach, innerhalb welcher wirtschaftsrechtlicher Rechtsinstrumente der ziviljustiziellen Zusammenarbeit (Art. 81 AEUV) der Neuregelung Bedeutung zukommt.
Die Vollziehung eines inländischen Arrestbefehls ist nur innerhalb einer Monatsfrist ab seiner Verkündung bzw. ab Zustellung des Arrestbefehls an den Antragsteller möglich ( 929 Abs. 2 ZPO). Anhand eines Altfalls hat der EuGH entschieden, dass diese Vollziehungsfrist auch bei der Vollziehung ausländischer "Arrestbefehle" nach deren Vollstreckbarerklärung im Inland angewendet werden darf. Durch seine Entscheidung hat der EuGH Überlegungen zum Umgang mit ausländischen Arrestbefehlen angestoßen, die im Inland nach der derzeit geltenden Fassung der EuGVVO zu vollziehen sind. Dies macht insofern einen Unterschied, als die Neufassung der EuGVVO im Gegensatz zur Vorfassung kein Vollstreckbarerklärungsverfahren mehr vorsieht. Die bestehenden Rechtsunsicherheiten riefen den Gesetzgeber auf den Plan, der hierzu vor kurzem eine neue Regelung verabschiedet hat. Der folgende Beitrag stellt nicht nur die Entwicklung dieser neuen Vorschrift und deren Inhalt dar, sondern zeigt
Die EuGVVO wird zwar zu Recht viel gelobt. Einfach zu handhaben ist sie aber nicht. Denn die Verordnung enthält ein „Knäuel“ von Regelungen zur internationalen bzw. zur örtlichen Zuständigkeit. Der folgende Beitrag will dieses „Knäuel“ entflechten und dem Rechtsanwender darüber hinaus Hilfestellungen bei der Anwendung der zuständigkeitsrechtlichen Verweisungsnormen in dieser Verordnung geben.
Ein Schwerpunkt des Kinderehenbekämpfungsgesetzes liegt in der Beurteilung von Ehen, die im Ausland mit Minderjährigen geschlossen worden sind. Die Entscheidungen der deutschen Gerichte hierzu sind im Regelfall einzeln kommentiert worden. Ein Gesamtüberblick fehlt. Der folgende Beitrag will diese Lücke schließen.
The article discusses a court ruling of the Higher Regional Court of Hamm on jurisdiction concerning the “Diesel emission scandal”. The plaintiff had his domicile in Bielefeld (Germany). He bought a car in Cologne (Germany) where the seller had his domicile. Later on, the plaintiff brought an action for damages and for a declaratory judgment against the seller, the importer of the car (domicile: Darmstadt, Germany) and the producer of the car (domicile: in the Czech Republic) before the District Court of Bielefeld. The plaintiff argued that the producer of the car had used illegal software to manipulate the results of the emissions tests. He based his claim on tort. Against the first defendant he also claimed his warranty rights. In order to sue all three defendants in one trial the plaintiff requested the District Court of Bielefeld to ask the Higher Regional Court of Hamm to determine jurisdiction. In its decision the Court in Hamm took into account Article 8 No. 1 of the Brussels Ibis Regulation and § 36 I No. 3, II of the German Code of Civil Procedure.
Anknüpfend an den letztjährigen Bericht des Autors (Wagner NJW 2020, NJW Jahr 2020 Seite 1864) informiert dieser Beitrag die Praxis wiederum über die jüngsten rechtsvereinheitlichenden Arbeiten in Brüssel in der justiziellen Zusammenarbeit in Zivilsachen sowie über den Stand der deutschen „Begleitgesetzgebung“. Kurz thematisiert wird außerdem das Verhältnis zum Vereinigten Königreich nach dem Brexit. Darüber hinaus wird ein Blick in die Pläne zur justiziellen Zusammenarbeit in Zivilsachen geworfen und die aktuelle Rechtsprechung des EuGH auf diesem Rechtsgebiet vorgestellt.
Grundzüge der EuGVVO
(2021)
Pathologisches Grübeln
(2021)
This study examines the institutionalization of information technologies for policy formulation by investigating the case of eNAP. The digital tool was introduced in the spring of 2018 with the aim of supporting and improving sustainability impact assessments (SIAs) within the German Federal Government. Applying a neo-institutional perspective, this study shows how a tool like eNAP is embedded into prevailing regulative, normative, and cultural–cognitive structures. Findings from 10 semi-structured interviews indicate that the application of eNAP varies according to intra-ministerial coordination practices and portfolio-specific information-processing schemata. Overall, the tool serves to translate the abstract regulation to conduct an SIA, as well as to translate the vague norm of “sustainability” into a concrete assessment requirement, thereby helping increase policy officials’ awareness of sustainability goals. However, consistent with previous studies, great importance is not attached to SIAs in policy formulation, and prevailing norms and routines make the implementation of eNAP to increase the use of evidence or in-depth considerations of policy alternatives and their consequences unlikely.
Der Diplomat und die Päpste
(2021)
Nach dem Ersten Weltkrieg wurde Diego von Bergen zum ersten deutschen Botschafter beim Heiligen Stuhl ernannt und vertrat die Weimarer Republik und Hitler-Deutschland bis 1943 am Vatikan. Bis weit in die Nachkriegszeit hinein galt er als der „nationalsozialistischen Mystik nicht empfänglich“.Da in der historischen Forschung inzwischen Konsens darüber herrscht, dass das Auswärtige Amt die Gewaltpolitik des NS-Regimes überall und zu jeder Zeit mitgetragen hat, liefert die Studie eine überfällige Neubewertung von Hitlers dienstältestem Botschafter. Sie schärft nicht nur das Bild des Amts als Akteur der Außenpolitik des Dritten Reichs, sondern lotet Handlungsspielräume des Botschafters aus und verortet ihn als Gegenspieler des Papstes. Zudem gelingt es methodisch innovativ, die personalpolitische Entwicklung des Amts und der Botschaft epochenübergreifend mitzuberücksichtigen.
A matter of concern
(2021)
Neurons are post-mitotic cells in the brain and their integrity is of central importance to avoid neurodegeneration. Yet, the inability of self-replenishment of post-mitotic cells results in the need to withstand challenges from numerous stressors during life. Neurons are exposed to oxidative stress due to high oxygen consumption during metabolic activity in the brain. Accordingly, DNA damage can occur and accumulate, resulting in genome instability. In this context, imbalances in brain trace element homeostasis are a matter of concern, especially regarding iron, copper, manganese, zinc, and selenium. Although trace elements are essential for brain physiology, excess and deficient conditions are considered to impair neuronal maintenance. Besides increasing oxidative stress, DNA damage response and repair of oxidative DNA damage are affected by trace elements. Hence, a balanced trace element homeostasis is of particular importance to safeguard neuronal genome integrity and prevent neuronal loss. This review summarises the current state of knowledge on the impact of deficient, as well as excessive iron, copper, manganese, zinc, and selenium levels on neuronal genome stability
Spherulite-related space-charge electret properties of polypropylene (PP) have been widely discussed in the past decades. In the present paper, a less-common crystalline structure in PP-transcrystalline PP-is studied regarding its electret behavior in comparison with the typical spherulitic morphology. Polarized light microscopy and differential scanning calorimetry were employed to characterize the crystallite types and crystallinities of transcrystalline and spherulitic PP. Their electret functionality is investigated by means of thermally stimulated discharge experiments, where the cross-over phenomenon is observed on transcrystalline PP films, whereas surface-potential saturation and undercharging on the surface occur on the spherulitic samples. Besides, an asymmetrical behavior of positive and negative surface-charge stabilities is found on PP with spherulites, the negatively charged spherulitic surfaces show a better charge stability. It is shown that PP electrets are very sensitive to changes in the microscopic crystalline structures and their interfaces as well as in the molecular conformations controlled through adjustments of the respective processing steps. In addition, surface and bulk nanocomposites of PP or low-density polyethylene with inorganic particles are included in the comparison. In view of recent developments in the areas of PP-based electret-fiber filters and cellular-foam ferroelectrets, the observed changes in the charge-storage properties may have particular relevance, as the required film, fiber, or foam processing might significantly modify crystalline morphologies and nano-scale interfaces in PP electrets. Limitations in the charge-storage capabilities of interface structures may also be of interest in the context of high-voltage electrical-insulation materials where reduced space-charge accumulation and slightly increased charge transport can be advantageous.
Knowledge of pressure-dependent static and dynamic moduli of porous reservoir rocks is of key importance for evaluating geological setting of a reservoir in geo-energy applications. We examined experimentally the evolution of static and dynamic bulk moduli for porous Bentheim sandstone with increasing confining pressure up to about 190 MPa under dry and water-saturated conditions. The static bulk moduli (K-s) were estimated from stress-volumetric strain curves while dynamic bulk moduli (K-d) were derived from the changes in ultrasonic P- and S- wave velocities (similar to 1 MHz) along different traces, which were monitored simultaneously during the entire deformation. In conjunction with published data of other porous sandstones (Berea, Navajo and Weber sandstones), our results reveal that the ratio between dynamic and static bulk moduli (K-d/K-s) reduces rapidly from about 1.5 - 2.0 at ambient pressure to about 1.1 at high pressure under dry conditions and from about 2.0 - 4.0 to about 1.5 under water-saturated conditions, respectively. We interpret such a pressure-dependent reduction by closure of narrow (compliant) cracks, highlighting thatK(d)/K(s)is positively correlated with the amount of narrow cracks. Above the crack closure pressure, where equant (stiff) pores dominate the void space,K-d/K(s)is almost constant. The enhanced difference between dynamic and static bulk moduli under water saturation compared to dry conditions is possibly caused by high pore pressure that is locally maintained if measured using high-frequency ultrasonic wave velocities. In our experiments, the pressure dependence of dynamic bulk modulus of water-saturated Bentheim sandstone at effective pressures above 5 MPa can be roughly predicted by both the effective medium theory (Mori-Tanaka scheme) and the squirt-flow model. Static bulk moduli are found to be more sensitive to narrow cracks than dynamic bulk moduli for porous sandstones under dry and water-saturated conditions.
Membrane sterol composition in Arabidopsis thaliana affects root elongation via auxin biosynthesis
(2021)
Plant membrane sterol composition has been reported to affect growth and gravitropism via polar auxin transport and auxin signaling. However, as to whether sterols influence auxin biosynthesis has received little attention. Here, by using the sterol biosynthesis mutant cyclopropylsterol isomerase1-1 (cpi1-1) and sterol application, we reveal that cycloeucalenol, a CPI1 substrate, and sitosterol, an end-product of sterol biosynthesis, antagonistically affect auxin biosynthesis. The short root phenotype of cpi1-1 was associated with a markedly enhanced auxin response in the root tip. Both were neither suppressed by mutations in polar auxin transport (PAT) proteins nor by treatment with a PAT inhibitor and responded to an auxin signaling inhibitor. However, expression of several auxin biosynthesis genes TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS1 (TAA1) was upregulated in cpi1-1. Functionally, TAA1 mutation reduced the auxin response in cpi1-1 and partially rescued its short root phenotype. In support of this genetic evidence, application of cycloeucalenol upregulated expression of the auxin responsive reporter DR5:GUS (beta-glucuronidase) and of several auxin biosynthesis genes, while sitosterol repressed their expression. Hence, our combined genetic, pharmacological, and sterol application studies reveal a hitherto unexplored sterol-dependent modulation of auxin biosynthesis during Arabidopsis root elongation.
Firms increasingly use ideas from online innovation communities to solve problems or to better address customer needs. However, in many cases the number of submitted ideas has exploded, it leads to an information overload that firms hardly can handle considering their limited cognitive resources. Therefore, we use the Elaboration Likelihood Model to distinguish between the quick and lean idea preselection process as a peripheral route of information processing and the subsequent idea review process as a central route of information processing. In our empirical study with a sample of more than 163,000 ideas collected from the Xiaomi MIUI community, we analyse influencing factors that increase the likelihood of ideas being preselected or reviewed. Results show that user status, user initiative contribution, and community recognition have a significantly positive influence on idea preselction, whereas user response contribution has no influence. Idea presentation characteristics have an inverted U-curve relationship with idea adoption. Community absorptive capacity has a moderate effect on the curvilinear relationship between idea description length and idea adoption.
Due to their electrically polarized air-filled internal pores, optimized ferroelectrets exhibit a remarkable piezoelectric response, making them suitable for energy harvesting. Expanded polytetrafluoroethylene (ePTFE) ferroelectret films are laminated with two fluorinated-ethylene-propylene (FEP) copolymer films and internally polarized by corona discharge. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)-coated spandex fabric is employed for the electrodes to assemble an all-organic ferroelectret nanogenerator (FENG). The outer electret-plus-electrode double layers form active device layers with deformable electric dipoles that strongly contribute to the overall piezoelectric response in the proposed concept of wearable nanogenerators. Thus, the FENG with spandex electrodes generates a short-circuit current which is twice as high as that with aluminum electrodes. The stacking sequence spandex/FEP/ePTFE/FEP/ePTFE/FEP/spandex with an average pore size of 3 mu m in the ePTFE films yields the best overall performance, which is also demonstrated by the displacement-versus-electric-field loop results. The all-organic FENGs are stable up to 90 degrees C and still perform well 9 months after being polarized. An optimized FENG makes three light emitting diodes (LEDs) blink twice with the energy generated during a single footstep. The new all-organic FENG can thus continuously power wearable electronic devices and is easily integrated, for example, with clothing, other textiles, or shoe insoles.
How different are the results of constant-rate resetting of anomalous-diffusion processes in terms of their ensemble-averaged versus time-averaged mean-squared displacements (MSDs versus TAMSDs) and how does stochastic resetting impact nonergodicity? We examine, both analytically and by simulations, the implications of resetting on the MSD- and TAMSD-based spreading dynamics of particles executing fractional Brownian motion (FBM) with a long-time memory, heterogeneous diffusion processes (HDPs) with a power-law space-dependent diffusivity D(x) = D0|x|gamma and their "combined" process of HDP-FBM. We find, inter alia, that the resetting dynamics of originally ergodic FBM for superdiffusive Hurst exponents develops disparities in scaling and magnitudes of the MSDs and mean TAMSDs indicating weak ergodicity breaking. For subdiffusive HDPs we also quantify the nonequivalence of the MSD and TAMSD and observe a new trimodal form of the probability density function. For reset FBM, HDPs and HDP-FBM we compute analytically and verify by simulations the short-time MSD and TAMSD asymptotes and long-time plateaus reminiscent of those for processes under confinement. We show that certain characteristics of these reset processes are functionally similar despite a different stochastic nature of their nonreset variants. Importantly, we discover nonmonotonicity of the ergodicitybreaking parameter EB as a function of the resetting rate r. For all reset processes studied we unveil a pronounced resetting-induced nonergodicity with a maximum of EB at intermediate r and EB similar to(1/r )-decay at large r. Alongside the emerging MSD-versus-TAMSD disparity, this r-dependence of EB can be an experimentally testable prediction. We conclude by discussing some implications to experimental systems featuring resetting dynamics.
Elucidation of the reaction mechanism for the synthesis of ZnGeN2 through Zn2GeO4 ammonolysis
(2021)
Ternary II-IV-N-2 materials have been considered as a promising class of materials that combine photovoltaic performance with earth-abundance and low toxicity. When switching from binary III-V materials to ternary II-IV-N-2 materials, further structural complexity is added to the system that may influence its optoelectronic properties. Herein, we present a systematic study of the reaction of Zn2GeO4 with NH3 that produces zinc germanium oxide nitrides, and ultimately approach stoichiometric ZnGeN2, using a combination of chemical analyses, X-ray powder diffraction and DFT calculations. Elucidating the reaction mechanism as being dominated by Zn and O extrusion at the later reaction stages, we give an insight into studying structure-property relationships in this emerging class of materials.
Mitochondria are critical for hypothalamic function and regulators of metabolism. Hypothalamic mitochondrial dysfunction with decreased mitochondrial chaperone expression is present in type 2 diabetes (T2D). Recently, we demonstrated that a dysregulated mitochondrial stress response (MSR) with reduced chaperone expression in the hypothalamus is an early event in obesity development due to insufficient insulin signaling. Although insulin activates this response and improves metabolism, the metabolic impact of one of its members, the mitochondrial chaperone heat shock protein 10 (Hsp10), is unknown. Thus, we hypothesized that a reduction of Hsp10 in hypothalamic neurons will impair mitochondrial function and impact brain insulin action. Therefore, we investigated the role of chaperone Hsp10 by introducing a lentiviral-mediated Hsp10 knockdown (KD) in the hypothalamic cell line CLU-183 and in the arcuate nucleus (ARC) of C57BL/6N male mice. We analyzed mitochondrial function and insulin signaling utilizing qPCR, Western blot, XF96 Analyzer, immunohistochemistry, and microscopy techniques. We show that Hsp10 expression is reduced in T2D mice brains and regulated by leptin in vitro. Hsp10 KD in hypothalamic cells induced mitochondrial dysfunction with altered fatty acid metabolism and increased mitochondria-specific oxidative stress resulting in neuronal insulin resistance. Consequently, the reduction of Hsp10 in the ARC of C57BL/6N mice caused hypothalamic insulin resistance with acute liver insulin resistance.
Introduction
(2021)
In this report we describe Cy5-dUTP labelling of recombinase-polymerase-amplification (RPA) products directly during the amplification process for the first time. Nucleic acid amplification techniques, especially polymerase-chain-reaction as well as various isothermal amplification methods such as RPA, becomes a promising tool in the detection of pathogens and target specific genes. Actually, RPA even provides more advantages. This isothermal method got popular in point of care diagnostics because of its speed and sensitivity but requires pre-labelled primer or probes for a following detection of the amplicons. To overcome this disadvantages, we performed an labelling of RPA-amplicons with Cy5-dUTP without the need of pre-labelled primers. The amplification results of various multiple antibiotic resistance genes indicating great potential as a flexible and promising tool with high specific and sensitive detection capabilities of the target genes. After the determination of an appropriate rate of 1% Cy5-dUTP and 99% unlabelled dTTP we were able to detect the bla(CTX-M15) gene in less than 1.6E-03 ng genomic DNA corresponding to approximately 200 cfu of Escherichia coli cells in only 40 min amplification time.
Background
Relatively little is known about protective factors and the emergence and maintenance of positive outcomes in the field of adolescents with chronic conditions. Therefore, the primary aim of the study is to acquire a deeper understanding of the dynamic process of resilience factors, coping strategies and psychosocial adjustment of adolescents living with chronic conditions.
Methods/design
We plan to consecutively recruit N = 450 adolescents (12–21 years) from three German patient registries for chronic conditions (type 1 diabetes, cystic fibrosis, or juvenile idiopathic arthritis). Based on screening for anxiety and depression, adolescents are assigned to two parallel groups – “inconspicuous” (PHQ-9 and GAD-7 < 7) vs. “conspicuous” (PHQ-9 or GAD-7 ≥ 7) – participating in a prospective online survey at baseline and 12-month follow-up. At two time points (T1, T2), we assess (1) intra- and interpersonal resiliency factors, (2) coping strategies, and (3) health-related quality of life, well-being, satisfaction with life, anxiety and depression. Using a cross-lagged panel design, we will examine the bidirectional longitudinal relations between resiliency factors and coping strategies, psychological adaptation, and psychosocial adjustment. To monitor Covid-19 pandemic effects, participants are also invited to take part in an intermediate online survey.
Discussion
The study will provide a deeper understanding of adaptive, potentially modifiable processes and will therefore help to develop novel, tailored interventions supporting a positive adaptation in youths with a chronic condition. These strategies should not only support those at risk but also promote the maintenance of a successful adaptation.
Trial registration
German Clinical Trials Register (DRKS), no. DRKS00025125. Registered on May 17, 2021.
Climate science provides strong evidence of the necessity of limiting global warming to 1.5 °C, in line with the Paris Climate Agreement. The IPCC 1.5 °C special report (SR1.5) presents 414 emissions scenarios modelled for the report, of which around 50 are classified as '1.5 °C scenarios', with no or low temperature overshoot. These emission scenarios differ in their reliance on individual mitigation levers, including reduction of global energy demand, decarbonisation of energy production, development of land-management systems, and the pace and scale of deploying carbon dioxide removal (CDR) technologies. The reliance of 1.5 °C scenarios on these levers needs to be critically assessed in light of the potentials of the relevant technologies and roll-out plans. We use a set of five parameters to bundle and characterise the mitigation levers employed in the SR1.5 1.5 °C scenarios. For each of these levers, we draw on the literature to define 'medium' and 'high' upper bounds that delineate between their 'reasonable', 'challenging' and 'speculative' use by mid century. We do not find any 1.5 °C scenarios that stay within all medium upper bounds on the five mitigation levers. Scenarios most frequently 'over use' CDR with geological storage as a mitigation lever, whilst reductions of energy demand and carbon intensity of energy production are 'over used' less frequently. If we allow mitigation levers to be employed up to our high upper bounds, we are left with 22 of the SR1.5 1.5 °C scenarios with no or low overshoot. The scenarios that fulfil these criteria are characterised by greater coverage of the available mitigation levers than those scenarios that exceed at least one of the high upper bounds. When excluding the two scenarios that exceed the SR1.5 carbon budget for limiting global warming to 1.5 °C, this subset of 1.5 °C scenarios shows a range of 15–22 Gt CO2 (16–22 Gt CO2 interquartile range) for emissions in 2030. For the year of reaching net zero CO2 emissions the range is 2039–2061 (2049–2057 interquartile range).
Seit dem 01. 04. 2017 erfolgte eine umfangreiche Reform der Psychotherapie-Richtlinie. Neben der Einführung neuer Leistungen (z. B. Akutbehandlung, psychotherapeutische Sprechstunde) wurden auch Änderungen im Ablauf und der Beantragung von Psychotherapie beschlossen. Beispielsweise ist der Bericht an den Gutachter bzw. die Gutachterin seltener eine notwendige Voraussetzung zur Durchführung einer psychotherapeutischen Behandlung, als dass zuvor der Fall war. Im Zuge der Reform wurde auch der Leitfaden für die Gestaltung des Berichts an den Gutachter bzw. die Gutachterin überarbeitet.
Vor dem Hintergrund der Psychotherapie-Richtlinien-Reform ist das Werk „Leitfaden für den VT-Bericht an den Gutachter“ von Daniel Surall und Oliver Kunz sehr willkommen. Das Buch gliedert sich insgesamt in zehn Kapitel, in denen die Autoren ausführlich auf den reformierten Bericht an den Gutachter bzw. an die Gutachterin eingehen. In den ersten beiden Kapiteln fassen die Autoren die Änderungen zur Psychotherapie-Richtlinie und im Bericht an den Gutachter / die Gutachterin zusammen. In den folgenden sechs Kapiteln wird auf die einzelnen Abschnitte des neuen Berichts an den Gutachter/die Gutachterin eingegangen. Sehr hilfreich ist hierbei, dass die Autoren zahlreiche Fallbeispiele nutzen, um die einzelnen Abschnitte des Berichts an den Gutachter/die Gutachterin zu erläutern. Auch die übersichtliche Darstellungsform in Form von Tabellen (z. B. zur Darstellung der Verhaltensanalyse) erleichtert den Leser_innen die Nachvollziehbarkeit der Inhalte. Erfreulich ist auch, dass die Autoren hinsichtlich der Antragstellung auch immer auf Unterschiede zwischen erwachsenen Patient_innen und Kindern und Jugendlichen eingehen. Im neunten Kapitel des Leitfadens wird ausführlicher das Thema Umwandlungs- und Fortführungsanträge aufgegriffen. Dies ist insbesondere sinnvoll, da nach der neuen Psychotherapie-Richtlinie für Kurzzeitanträge in der Regel keine Berichtspflicht besteht und Umwandlungs- und Fortführungsanträge in der Praxis häufiger als zuvor von Relevanz sein dürften. Im zehnten Kapitel wird in knapper Weise darauf eingegangen, wie bei Ablehnung oder Kürzung von beantragten Leistungen vorgegangen werden kann.
Das Buch umfasst einen umfangreichen Anhang (67 Seiten), in dem Beispiele für Berichte an den Gutachter / die Gutachterin und Behandlungspläne für verschiedene psychische Störungen zu finden sind. Auch hierbei werden sowohl Berichte für Erwachsene als auch für Kinder und Jugendliche präsentiert. Zudem beinhaltet der Anhang des Buches das Berner Inventar für Therapieziele, Auszüge aus dem AMDP-Befundbogen (Arbeitsgemeinschaft Methodik und Dokumentation in der Psychiatrie, 2018)<\litr>, den Leitfaden zum Erstellen des Berichts an die Gutachter_innen (PTV 3) sowie einer Gegenüberstellung des alten und des neuen Leitfadens für den Bericht an die Gutachter_innen.
Bei dem von Surall und Kunz vorgelegten Buch handelt es sich um einen äußerst hilfreichen Leitfaden, der Therapeut:innen bei der Abfassung des Berichts an den Gutachter / die Gutachterin im Rahmen der Verhaltenstherapie unterstützen kann. Hierbei kann der Leitfaden Psychotherapeut_innen in Ausbildung bei der Abfassung ihrer ersten Anträge unterstützen. Aber auch erfahrenen Kolleg_innen können bei dem Übergang in die neuen Antragsformalitäten, die mit der Reform der Psychotherapie-Richtlinie einhergingen, unterstützen werden. Hierbei ist insbesondere die Im Anhang befindliche Gegenüberstellung des alten und des neuen Leitfadens für den Bericht an den Gutachter / die Gutachterin hilfreich, um sich einen schnellen Überblick über die Änderungen zu verschaffen. Insgesamt werden die einzelnen Abschnitte des Berichts an den Gutachter / die Gutachterin sehr gut strukturiert und verständlich erläutert. Die vielen Beispiele und die ausführlichen Materialien im Anhang ergänzen zudem die Erläuterungen und erleichtern das Verständnis. Zu Beginn des Buches wäre zudem noch eine Abbildung hilfreich gewesen, die den Ablauf der Beantragung von Psychotherapie schematisch darstellt, um einen genaueren Überblick über die Beantragung von Psychotherapie nach der neuen Psychotherapie-Richtlinie zu erhalten. Auch ein Stichwortverzeichnis würde die Suche nach bestimmten Inhalten erleichtern.
Zusammenfassend kann festgehalten werden, dass es sich bei dem Werk von Surall und Kunz um einen sehr empfehlenswerten Leitfaden handelt, der im Rahmen der Antragstellung von Verhaltenstherapie genutzt werden kann. Aufgrund der klaren Struktur und Anschaulichkeit durch viele Beispielanträge bringt das Buch alle Voraussetzungen mit, um sich als Standartwerk zu etablieren, dass Therapeut_innen bei der Beantragung von Verhaltenstherapie in äußerst hilfreicher Weise unterstützt.
Objective:
Therapist competence is considered essential for the success of psychotherapy. Feedback is an intervention which has the potential to improve therapist competence. The present study investigated whether competence feedback leads to an improvement of therapist competence and patient outcome.
Method:
Sixty-seven master-level clinical trainees were randomly assigned to either a competence feedback group (CFG) or a control group (CG). Patients with a diagnosis of major depression (N = 114) were randomly assigned to CFG or CG. Treatment included 20 individual sessions of cognitive behavioral therapy (CBT). In CFG, therapists received, parallel to the treatment, five competence feedbacks, based on videotaped therapy sessions. Independent raters assessed therapist competence with the Cognitive Therapy Scale (CTS) and provided the competence feedback. Patient outcome was evaluated with the Beck Depression Inventory-II (BDI-II) and therapeutic alliance (Helping Alliance Questionnaire [HAQ]) from both therapist's (HAQ-T) and patient's (HAQ-P) perspective were evaluated after each of the 20 sessions.
Results:
(a) Therapist competence (CTS) increased significantly more for CFG than CG. (b) Depression (BDI-II) decreased significantly across sessions for both groups, but without evidence for a group-differential benefit for the CFG. (c) Therapeutic alliance (HAQ-T/P) increased significantly across sessions for both groups from both perspectives, but without group differences. (d) There is a positive effect of BDI-II on CTS at the beginning and a negative effect of CTS on BDI-II at the end of therapy.
Conclusion:
Competence feedback improves therapists' independently rated competence, but there is no evidence that competence feedback in CBT leads to better outcome.
What is the public health significance of this article? This study suggests the substantial value of systematic competence feedback for improving therapist competence in the psychotherapy of depression. No significant effect of competence feedback on the reduction of reported depressive symptoms was found.
Transitioning German road transport partially to hydrogen energy is among the possibilities being discussed to help meet national climate targets. This study investigates impacts of a hypothetical, complete transition from conventionally-fueled to hydrogen-powered German transport through representative scenarios. Our results show that German emissions change between -179 and +95 MtCO(2)eq annually, depending on the scenario, with renewable-powered electrolysis leading to the greatest emissions reduction, while electrolysis using the fossilintense current electricity mix leads to the greatest increase. German energy emissions of regulated pollutants decrease significantly, indicating the potential for simultaneous air quality improvements. Vehicular hydrogen demand is 1000 PJ annually, requiring 446-525 TWh for electrolysis, hydrogen transport and storage, which could be supplied by future German renewable generation, supporting the potential for CO2-free hydrogen traffic and increased energy security. Thus hydrogen-powered transport could contribute significantly to climate and air quality goals, warranting further research and political discussion about this possibility.
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.
Remote sensing plays an increasingly key role in the determination of soil organic carbon (SOC) stored in agriculturally managed topsoils at the regional and field scales. Contemporary Unmanned Aerial Systems (UAS) carrying low-cost and lightweight multispectral sensors provide high spatial resolution imagery (<10 cm). These capabilities allow integrate of UAS-derived soil data and maps into digitalized workflows for sustainable agriculture. However, the common situation of scarce soil data at field scale might be an obstacle for accurate digital soil mapping. In our case study we tested a fixed-wing UAS equipped with visible and near infrared (VIS-NIR) sensors to estimate topsoil SOC distribution at two fields under the constraint of limited sampling points, which were selected by pedological knowledge. They represent all releva nt soil types along an erosion-deposition gradient; hence, the full feature space in terms of topsoils' SOC status. We included the Topographic Position Index (TPI) as a co-variate for SOC prediction. Our study was performed in a soil landscape of hummocky ground moraines, which represent a significant of global arable land. Herein, small scale soil variability is mainly driven by tillage erosion which, in turn, is strongly dependent on topography. Relationships between SOC, TPI and spectral information were tested by Multiple Linear Regression (MLR) using: (i) single field data (local approach) and (ii) data from both fields (pooled approach). The highest prediction performance determined by a leave-one-out-cross-validation (LOOCV) was obtained for the models using the reflectance at 570 nm in conjunction with the TPI as explanatory variables for the local approach (coefficient of determination (R-2) = 0.91; root mean square error (RMSE) = 0.11% and R-2 = 0.48; RMSE = 0.33, respectively). The local MLR models developed with both reflectance and TPI using values from all points showed high correlations and low prediction errors for SOC content (R-2 = 0.88, RMSE = 0.07%; R-2 = 0.79, RMSE = 0.06%, respectively). The comparison with an enlarged dataset consisting of all points from both fields (pooled approach) showed no improvement of the prediction accuracy but yielded decreased prediction errors. Lastly, the local MLR models were applied to the data of the respective other field to evaluate the cross-field prediction ability. The spatial SOC pattern generally remains unaffected on both fields; differences, however, occur concerning the predicted SOC level. Our results indicate a high potential of the combination of UAS-based remote sensing and environmental covariates, such as terrain attributes, for the prediction of topsoil SOC content at the field scale. The temporal flexibility of UAS offer the opportunity to optimize flight conditions including weather and soil surface status (plant cover or residuals, moisture and roughness) which, otherwise, might obscure the relationship between spectral data and SOC content. Pedologically targeted selection of soil samples for model development appears to be the key for an efficient and effective prediction even with a small dataset.
The Water Exhales
(2021)
Atemdarstellungen im Medium Comic sind ein durchaus ambivalentes Thema. Meines Wissens ist es einerseits recht selten, dass Figuren in Comics atmend gezeigt werden bzw. genauer: dass ihre reguläre Atmung explizit thematisiert wird. Andererseits beinhaltet fast jeder Comic Motive oder Praktiken, die mit dem Einsaugen und Ausstoßen von Atemluft zu tun haben: erleichtertes Seufzen etwa, sich Räuspern, Husten, Keuchen, Rauchen oder Riechen. Da in solchen Panels oder Panelsequenzen Atem bzw. Spielarten desselben besonders markiert sind, bietet es sich an, diese Szenen genauer zu analysieren und sich zu fragen, welchen Effekt Atemmotive an dieser Stelle für die Geschichte haben und auf welche Weise Atem jeweils sichtbar gemacht wird. Der Beitrag verfolgt das Ziel, exemplarisch Atemmotive zu diskutieren, um das vielfältige Spektrum ästhetisch-narrativer Atemdarstellungen in Comics anzudeuten.
Das Spannungsfeld zwischen dem Ausbau erneuerbarer Energien einerseits und Akzeptanzproblemen andererseits adressiert der Landesgesetzgeber Mecklenburg-Vorpommerns mit einem Beteiligungsgesetz zur verpflichtenden wirtschaftlichen Teilhabemöglichkeit. Dabei stellt sich die Frage nach der Vereinbarkeit mit geltendem Recht, insbesondere ob der Landesgesetzgeber gesetzgebungsbefugt ist. Darüber hinaus zeigt der Autor den Rahmen für eine Regelung auf und positioniert sich zu möglichen Grundrechtseingriffen durch eine solche Regelung. Die Aktualität der Untersuchung zeigt die gegen das Gesetz anhängige Verfassungsbeschwerde ebenso wie die dynamische Gesetzgebung – so statuiert § 36g Abs. 5 EEG nunmehr eine Länderöffnungsklausel.
Odd-chain fatty acids (OCFA) are inversely associated with type-2-diabetes in epidemiological studies. They are considered as a biomarker for dairy intake because fermentation in ruminants yields high amounts of propionate, which is used as the primer for lipogenesis. Recently, we demonstrated endogenous OCFA synthesis from propionate in humans and mice, but how this is affected by microbial colonization is still unexplored. Here, we investigated the effect of increasing microbiota complexity on hepatic lipid metabolism and OCFA levels in different dietary settings. Germ-free (GF), gnotobiotic (SIH, simplified human microbiota) or conventional (CONV) C3H/HeOuJ-mice were fed a CHOW or high-fat diet with inulin (HFI) to induce microbial fermentation. We found that hepatic lipogenesis was increased with increasing microbiota complexity, independently of diet. In contrast, OCFA formation was affected by diet as well as microbiota. On CHOW, hepatic OCFA and intestinal gluconeogenesis decreased with increasing microbiota complexity (GF > SIH > CONV), while cecal propionate showed a negative correlation with hepatic OCFA. On HFI, OCFA levels were highest in SIH and positively correlated with cecal propionate. The propionate content in the CHOW diet was 10 times higher than that of HFI. We conclude that bacterial propionate production affects hepatic OCFA formation, unless this effect is masked by dietary propionate intake.
This chapter consists of three parts. In the first part, I will give a short overview about the integration of the protection of the environment into German constitutional law. This section will start with the presentation of the relevant provision, Art. 20a BL. Then, I will elaborate on its legal character. In the second part, I will make some brief remarks on the practical implications of Art. 20a BL. Finally, I will present some preliminary conclusions.
Die vorliegende Dissertationsschrift gibt einen Einblick in die Einflüsse universitärer und schulischer Lerngelegenheiten des Schulpraktikums (Praxissemester) im Rahmen des lehramtsbezogenen Masterstudiums auf den Erwerb professioneller Kompetenzen. Darüber hinaus werden Einflüsse zuvor angebotener Kurse der Fachwissenschaften, Fachdidaktiken und Bildungswissenschaften aufgezeigt. Grundlage bilden Querschnitts- und Längsschnittserhebungen an der Universität Potsdam. Im Speziellen werden wesentliche Einflüsse des schulischen Einstiegs ins Praktikum, der universitären Vorbereitungskurse, der schulischen und universitären Unterrichtsbesprechungen, der mentoriellen Unterstützung an der Schule sowie der Abschlussgespräche durch die Ausbildungslehrkraft und die Schulleitung aufgezeigt. Die Ergebnisse werden anhand der Theorie diskutiert sowie im Blick auf die Qualifizierung von Ausbildungslehrkräften und die Nützlichkeit von Lerngelegenheiten diskutiert.
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.
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.</p> <br /> <br></p> <br /> 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.
Background: High-intensity muscle actions have the potential to temporarily improve the performance which has been denoted as postactivation performance enhancement.
Objectives: This study determined the acute effects of different stretch-shortening (fast vs. low) and strength (dynamic vs. isometric) exercises executed during one training session on subsequent balance performance in youth weightlifters.
Materials and Methods: Sixteen male and female young weightlifters, aged 11.3±0.6years, performed four strength exercise conditions in randomized order, including dynamic strength (DYN; 3 sets of 3 repetitions of 10 RM) and isometric strength exercises (ISOM; 3 sets of maintaining 3s of 10 RM of back-squat), as well as fast (FSSC; 3 sets of 3 repetitions of 20-cm drop-jumps) and slow (SSSC; 3 sets of 3 hurdle jumps over a 20-cm obstacle) stretch-shortening cycle protocols. Balance performance was tested before and after each of the four exercise conditions in bipedal stance on an unstable surface (i.e., BOSU ball with flat side facing up) using two dependent variables, i.e., center of pressure surface area (CoP SA) and velocity (CoP V).
Results: There was a significant effect of time on CoP SA and CoP V [F(1,60)=54.37, d=1.88, p<0.0001; F(1,60)=9.07, d=0.77, p=0.003]. In addition, a statistically significant effect of condition on CoP SA and CoP V [F(3,60)=11.81, d=1.53, p<0.0001; F(3,60)=7.36, d=1.21, p=0.0003] was observed. Statistically significant condition-by-time interactions were found for the balance parameters CoP SA (p<0.003, d=0.54) and CoP V (p<0.002, d=0.70). Specific to contrast analysis, all specified hypotheses were tested and demonstrated that FSSC yielded significantly greater improvements than all other conditions in CoP SA and CoP V [p<0.0001 (d=1.55); p=0.0004 (d=1.19), respectively]. In addition, FSSC yielded significantly greater improvements compared with the two conditions for both balance parameters [p<0.0001 (d=2.03); p<0.0001 (d=1.45)].
Conclusion: Fast stretch-shortening cycle exercises appear to be more effective to improve short-term balance performance in young weightlifters. Due to the importance of balance for overall competitive achievement in weightlifting, it is recommended that young weightlifters implement dynamic plyometric exercises in the fast stretch-shortening cycle during the warm-up to improve their balance performance.
An extinction-free estimator of the star formation rate (SFR) of galaxies is critical for understanding the high-redshift universe. To this end, the nearly linear, tight correlation of far-infrared (FIR), and radio luminosity of star-forming galaxies is widely used. While the FIR is linked to massive star formation, which also generates shock-accelerated cosmic-ray (CR) electrons and radio synchrotron emission, a detailed understanding of the underlying physics is still lacking. Hence, we perform three-dimensional magnetohydrodynamical (MHD) simulations of isolated galaxies over a broad range of halo masses and SFRs using the moving-mesh code AREPO, and evolve the CR proton energy density self-consistently. In post-processing, we calculate the steady-state spectra of primary, shock-accelerated and secondary CR electrons, which result from hadronic CR proton interactions with the interstellar medium. The resulting total radio luminosities correlate with the FIR luminosities as observed and are dominated by primary CR electrons if we account for anisotropic CR diffusion. The increasing contribution of secondary emission up to 30 per cent in starbursts is compensated by the larger bremsstrahlung and Coulomb losses. CR electrons are in the calorimetric limit and lose most of their energy through inverse Compton interactions with star light and cosmic microwave background (CMB) photons while less energy is converted into synchrotron emission. This implies steep steady-state synchrotron spectra in starbursts. Interestingly, we find that thermal free-free emission flattens the total radio spectra at high radio frequencies and reconciles calorimetric theory with observations while free-free absorption explains the observed low-frequency flattening towards the central regions of starbursts.
Current-day cosmic ray (CR) propagation studies use static Milky Way models and fit parametrized source distributions to data. Instead, we use three-dimensional magnetohydrodynamic (MHD) simulations of isolated galaxies with the moving-mesh code arepo that self-consistently accounts for hydrodynamic effects of CR protons. In post-processing, we calculate their steady-state spectra, taking into account all relevant loss processes. We show that this steady-state assumption is well justified in the disc and generally for regions that emit non-thermal radio and gamma rays. Additionally, we model the spectra of primary electrons, accelerated by supernova remnants, and secondary electrons and positrons produced in hadronic CR proton interactions with the gas. We find that proton spectra above 10 GeV only weakly depend on galactic radius, while they acquire a radial dependence at lower energies due to Coulomb interactions. Radiative losses steepen the spectra of primary CR electrons in the central galactic regions, while diffusive losses dominate in the outskirts. Secondary electrons exhibit a steeper spectrum than primaries because they originate from the transported steeper CR proton spectra. Consistent with Voyager-1 and AMS-02 data, our models (i) show a turnover of proton spectra below GeV energies due to Coulomb interactions so that electrons start to dominate the total particle spectra and (ii) match the shape of the positron fraction up to 10 GeV. We conclude that our steady-state CR modelling in MHD CR galaxy simulations is sufficiently realistic to capture the dominant transport effects shaping their spectra, arguing for a full MHD treatment to accurately model CR transport in the future.
The photochemical fragmentation of N-aroylsulfonamides 9 (ASAP) is a powerful method for the preparation of various biaryls. Compounds 9 are easily accessible in two steps from amines by treatment with arenesulfonyl chlorides and aroyl chlorides. Many of these compounds were prepared for the first time. The irradiation takes place in a previously developed continuous-flow reactor using inexpensive UVB or UVC fluorescent lamps. Isocyanates and sulphur dioxide are formed as the only by-products. The ASAP tolerates a variety of functional groups and is even suited for the preparation of phenylnaphthalenes and terphenyls. The ASAP mechanism was elucidated by interaction of photophysical and quantum chemical (DFT) methods and revealed a spirocyclic biradical as key intermediate.
Background
Building on the Realistic Accuracy Model, this paper explores whether it is easier for teachers to assess the achievement of some students than others. Accordingly, we suggest that certain individual characteristics of students, such as extraversion, academic self-efficacy, and conscientiousness, may guide teachers' evaluations of student achievement, resulting in more appropriate judgements and a stronger alignment of assigned grades with students' actual achievement level (as measured using standardized tests).
Aims
We examine whether extraversion, academic self-efficacy, and conscientiousness moderate the relations between teacher-assigned grades and students' standardized test scores in mathematics.
Sample
This study uses a representative sample of N = 5,919 seventh-grade students in Germany (48.8% girls; mean age: M = 12.5, SD = 0.62) who participated in a national, large-scale assessment focusing on students' academic development.
Methods
We specified structural equation models to examine the inter-relations of teacher-assigned grades with students' standardized test scores in mathematics, Big Five personality traits, and academic self-efficacy, while controlling for students' socioeconomic status, gender, and age.
Results
The correlation between teacher-assigned grades and standardized test scores in mathematics was r = .40. Teacher-assigned grades more closely related to standardized test scores when students reported higher levels of conscientiousness (beta = .05, p = .002). Students' extraversion and academic self-efficacy did not moderate the relationship between teacher-assigned grades and standardized test scores.
Conclusions
Our findings indicate that students' conscientiousness is a personality trait that seems to be important when it comes to how closely mathematics teachers align their grades to standardized test scores.
The Big Five personality traits play a major role in student achievement. As such, there is consistent evidence that students that are more conscientious receive better teacher-assigned grades in secondary school. However, research often does not support the claim that students that are more conscientious similarly achieve higher scores in domain-specific standardized achievement tests. Based on the Invest-and-Accrue Model, we argue that conscientiousness explains to some extent why certain students receive better grades despite similar academic accomplishments (i.e., achieving similar scores in domain-specific standardized achievement tests). Therefore, the present study examines to what extent the relationship between student personality and teacher-assigned grades consists of direct as opposed to indirect associations (via subject-specific standardized test scores). We used a representative sample of 14,710 ninth-grade students to estimate these direct and indirect pathways in mathematics and German. Structural equation models showed that test scores explained between 8 and 11% of the variance in teacher-assigned grades in mathematics and German. The Big Five personality traits in students additionally explained between 8 and 10% of the variance in grades. Finally, the personality-grade relationship consisted of direct (0.02 | β| ≤ 0.27) and indirect associations via test scores (0.01 | β| ≤ 0.07). Conscientiousness explained discrepancies between teacher-assigned grades and students’ scores in domain-specific standardized tests to a greater extent than any of the other Big Five personality traits. Our findings suggest that students that are more conscientious may invest more effort to accomplish classroom goals, but fall short of mastery.
er vorliegende Beitrag beschäftigt sich mit den Publikationen, die in der Zeitschrift für Erziehungswissenschaft (ZfE) in den Jahren 1998–2017 veröffentlicht wurden. Angesichts der Veränderungen in der erziehungswissenschaftlichen Forschungslandschaft in der jüngeren Vergangenheit untersuchen wir, inwiefern sich eine veränderte Schwerpunktsetzung auch in den Beiträgen der ZfE nachweisen lassen. Dazu führen wir zunächst eine quantitative Textanalyse durch und identifizieren die häufigsten sowie die charakteristischen Bigramme (Zweiwortsequenzen) in vier aufeinanderfolgenden Fünfjahres-Abschnitten (1998–2002, 2003–2007, 2008–2012, 2013–2017). Zudem prüfen wir, inwiefern bestimmte Wortstämme (bspw. „erziehungswissenschaft“, „bildungsforsch“, „didakt“) über die Jahre hinweg häufiger auftreten. Schließlich erstellen wir mit dem Textmining Tool Leximancer™ concept maps, die Hinweise auf die semantische Struktur der Themengebiete und Schlüsselkonzepte geben. Die Ergebnisse deuten darauf hin, dass im gesamten Zeitraum mehrheitlich Beiträge mit empirischem Fokus publiziert wurden, ein inhaltlicher Fokus auf sozialen Aspekten von Bildung lag und die Beschäftigung mit der allgemeinen Erziehungswissenschaft abnahm.
Epigenetic DNA methylation of EBI3 modulates human interleukin-35 formation via NFkB signaling
(2021)
Ulcerative colitis (UC), a severe chronic disease with unclear etiology that is associated with increased risk for colorectal cancer, is accompanied by dysregulation of cytokines. Epstein-Barr virus-induced gene 3 (EBI3) encodes a subunit in the unique heterodimeric IL-12 cytokine family of either pro- or anti-inflammatory function. After having recently demonstrated that upregulation of EBI3 by histone acetylation alleviates disease symptoms in a dextran sulfate sodium (DSS)-treated mouse model of chronic colitis, we now aimed to examine a possible further epigenetic regulation of EBI3 by DNA methylation under inflammatory conditions. Treatment with the DNA methyltransferase inhibitor (DNMTi) decitabine (DAC) and TNF alpha led to synergistic upregulation of EBI3 in human colon epithelial cells (HCEC). Use of different signaling pathway inhibitors indicated NF kappa B signaling was necessary and proportional to the synergistic EBI3 induction. MALDI-TOF/MS and HPLC-ESIMS/MS analysis of DAC/TNF alpha-treated HCEC identified IL-12p35 as the most probable binding partner to form a functional protein. EBI3/IL-12p35 heterodimers (IL-35) induce their own gene upregulation, something that was indeed observed in HCEC cultured with media from previously DAC/TNF alpha-treated HCEC. These results suggest that under inflammatory and demethylating conditions the upregulation of EBI3 results in the formation of anti-inflammatory IL-35, which might be considered as a therapeutic target in colitis.
Diagenetic trends of synthetic reservoir sandstone properties assessed by digital rock physics
(2021)
Quantifying interactions and dependencies among geometric, hydraulic and mechanical properties of reservoir sandstones is of particular importance for the exploration and utilisation of the geological subsurface and can be assessed by synthetic sandstones comprising the microstructural complexity of natural rocks. In the present study, three highly resolved samples of the Fontainebleau, Berea and Bentheim sandstones are generated by means of a process-based approach, which combines the gravity-driven deposition of irregularly shaped grains and their diagenetic cementation by three different schemes. The resulting evolution in porosity, permeability and rock stiffness is examined and compared to the respective micro-computer tomographic (micro-CT) scans. The grain contact-preferential scheme implies a progressive clogging of small throats and consequently produces considerably less connected and stiffer samples than the two other schemes. By contrast, uniform quartz overgrowth continuously alters the pore space and leads to the lowest elastic properties. The proposed stress-dependent cementation scheme combines both approaches of contact-cement and quartz overgrowth, resulting in granulometric, hydraulic and elastic properties equivalent to those of the respective micro-CT scans, where bulk moduli slightly deviate by 0.8%, 4.9% and 2.5% for the Fontainebleau, Berea and Bentheim sandstone, respectively. The synthetic samples can be further altered to examine the impact of mineral dissolution or precipitation as well as fracturing on various petrophysical correlations, which is of particular relevance for numerous aspects of a sustainable subsurface utilisation.
Digitizing grocery retailing
(2021)
Multiple emerging technologies both threaten grocers and offer them attractive opportunities to enhance their value propositions, improve processes, reduce costs, and therefore generate competitive advantages. Among the variety of technological innovations and considering the scarcity of resources, it is unclear which technologies to focus on and where to implement them in the value chain. To develop the most probable technology forecast that addresses the application of emerging technologies in the grocery value chain within the current decade, we conduct a two-stage Delphi study. Our results suggest a high relevance of almost all technologies. The panel is only skeptical about three specific projections. As a consequence, grocers are advised to build up knowledge regarding the application of these technologies in the most promising areas of their value chain.
Mergers play an important role in galaxy evolution. In particular, major mergers are able to have a transformative effect on galaxy morphology. In this paper, we investigate the role of magnetic fields in gas-rich major mergers. To this end, we run a series of high-resolution magnetohydrodynamic (MHD) zoom-in simulations with the moving-mesh code arepo and compare the outcome with hydrodynamic simulations run from the same initial conditions. This is the first time that the effect of magnetic fields in major mergers has been investigated in a cosmologically consistent manner. In contrast to previous non-cosmological simulations, we find that the inclusion of magnetic fields has a substantial impact on the production of the merger remnant. Whilst magnetic fields do not strongly affect global properties, such as the star formation history, they are able to significantly influence structural properties. Indeed, MHD simulations consistently form remnants with extended discs and well-developed spiral structure, whilst hydrodynamic simulations form more compact remnants that display distinctive ring morphology. We support this work with a resolution study and show that whilst global properties are broadly converged across resolution and physics models, morphological differences only develop given sufficient resolution. We argue that this is due to the more efficient excitement of a small-scale dynamo in higher resolution simulations, resulting in a more strongly amplified field that is better able to influence gas dynamics.
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.
A detailed investigation of the energy levels of perylene-3,4,9,10-tetracarboxylic tetraethylester as a representative compound for the whole family of perylene esters was performed. It was revealed via electrochemical measurements that one oxidation and two reductions take place. The bandgaps determined via the electrochemical approach are in good agreement with the optical bandgap obtained from the absorption spectra via a Tauc plot. In addition, absorption spectra in dependence of the electrochemical potential were the basis for extensive quantum-chemical calculations of the neutral, monoanionic, and dianionic molecules. For this purpose, calculations based on density functional theory were compared with post-Hartree-Fock methods and the CAM-B3LYP functional proved to be the most reliable choice for the calculation of absorption spectra. Furthermore, spectral features found experimentally could be reproduced with vibronic calculations and allowed to understand their origins. In particular, the two lowest energy absorption bands of the anion are not caused by absorption of two distinct electronic states, which might have been expected from vertical excitation calculations, but both states exhibit a strong vibronic progression resulting in contributions to both bands.
This paper reads ‘The Detainee’s Tale as told to Ali Smith’ (2016) as an exemplary demonstration of the work of world literature. Smith’s story articulates an ethics of reading that is grounded in the recipient’s openness to the singular, unpredictable, and unverifiable text of the other. More specifically, Smith’s account enables the very event that it painstakingly stages: the encounter with alterity and newness, which is both the theme of the narrative and the effect of the text on the reader. At the same time, however, the text urges to move from an ethics of literature understood as the responsible reception of the other by an individual reader to a more explicitly convivial and political ethics of commitment beyond the scene of reading.
Layer after Layer
(2021)
When the Royal Botanic Gardens at Kew in South London were opened to the general public in the 1840s, they were presented as a ‘world text’: a collection of flora from all over the world, with the spectacular tropical (read: colonial) specimens taking centre stage as indexes of Britain’s imperial supremacy. However, the one exotic plant species that preoccupied the British cultural imagination more than any other remained conspicuously absent from the collection: the banyan tree, whose non-transferability left a significant gap in the ‘text’ of the garden, thereby effectively puncturing the illusion of comprehensive global command that underpins the biopolitical designs of what Richard Grove has aptly dubbed ‘green imperialism’. This article demonstrates how, in the 19th and early 20th centuries, the banyan tree became an object of fascination and admiration for British scientists, painters, writers and photographers precisely because of its obstinate non-availability to colonial control and visual or even conceptual representability.
This paper reads ‘The Detainee’s Tale as told to Ali Smith’ (2016) as an exemplary demonstration of the work of world literature. Smith’s story articulates an ethics of reading that is grounded in the recipient’s openness to the singular, unpredictable, and unverifiable text of the other. More specifically, Smith’s account enables the very event that it painstakingly stages: the encounter with alterity and newness, which is both the theme of the narrative and the effect of the text on the reader. At the same time, however, the text urges to move from an ethics of literature understood as the responsible reception of the other by an individual reader to a more explicitly convivial and political ethics of commitment beyond the scene of reading.
Postcolonial criticism has repeatedly debunked the ostensible neutrality of the ‘world’ of world literature by pointing out that and how the contemporary world – whether conceived in terms of cosmopolitan conviviality or neoliberal globalization – cannot be understood without recourse to the worldly event of Europe’s colonial expansion. While we deem this critical perspective indispensable, we simultaneously maintain that to reduce ‘the world’ to the world-making impact of capital, colonialism, and patriarchy paints an overly deterministic picture that runs the risk of unwittingly reproducing precisely that dominant ‘oneworldness’ that it aims to critique. Moreover, the mere potentiality of alternative modes of world-making tends to disappear in such a perspective so that the only remaining option to think beyond oneworldness resides in the singularity claim. This insistence on singularity, however, leaves the relatedness of the single units massively underdetermined or denies it altogether. By contrast, we locate world literature in the conflicted space between the imperial imposition of a hierarchically stratified world (to which, as hegemonic forces tell us, ‘there is no alternative’) and the unrealized ‘undivided world’ that multiple minor cosmopolitan projects yet have to win. It is precisely the tension between these ‘two worlds’ that brings into view the crucial centrality not of the nodes in their alleged singularity but their specific relatedness to each other, that both impedes and energizes world literature today and renders it ineluctably postcolonial.
Die schrumpfende Mittelschicht ist nicht nur in der Öffentlichkeit ein vieldiskutierter Themenbereich. Eine Vielzahl an wissenschaftlichen Fachdisziplinen setzt sich aus unterschiedlichen Perspektiven mit der Mittelschicht im Kontext des Wandels von Schichtungsgefügen auseinander. Während die gesellschaftliche Mitte in Deutschland ein etabliertes Forschungsgebiet ist, liegen für Österreich hingegen bislang kaum Studien vor. Vor diesem Hintergrund vereint der Sammelband konzeptionelle und empirische Beiträge zur österreichischen Mittelschicht aus Soziologie, Politikwissenschaften, Staatswissenschaft, und Zeitgeschichte. Ziel ist die umfassende multidisziplinäre Darstellung des Status Quo der Mittelschicht in Österreich. Die Beiträge in diesem Sammelband bieten einen Überblick über historische Perspektiven, unterschiedliche Theorietraditionen, sowie gegenwärtige empirische Befunde und sozialpolitische Analysen.
'Complex systems are information processors' is a statement that is frequently made. Here we argue for the distinction between information processing-in the sense of encoding and transmitting a symbolic representation-and the formation of correlations (pattern formation/self-organisation). The study of both uses tools from information theory, but the purpose is very different in each case: explaining the mechanisms and understanding the purpose or function in the first case, versus data analysis and correlation extraction in the latter. We give examples of both and discuss some open questions. The distinction helps focus research efforts on the relevant questions in each case.
Insulin is the main anabolic hormone secreted by 13-cells of the pancreas stimulating the assimilation and storage of glucose in muscle and fat cells. It modulates the postprandial balance of carbohydrates, lipids and proteins via enhancing lipogenesis, glycogen and protein synthesis and suppressing glucose generation and its release from the liver. Resistance to insulin is a severe metabolic disorder related to a diminished response of peripheral tissues to the insulin action and signaling. This leads to a disturbed glucose homeostasis that precedes the onset of type 2 diabetes (T2D), a disease reaching epidemic proportions. A large number of studies reported an association between elevated circulating fatty acids and the development of insulin resistance. The increased fatty acid lipid flux results in the accumulation of lipid droplets in a variety of tissues. However, lipid intermediates such as diacylglycerols and ceramides are also formed in response to elevated fatty acid levels. These bioactive lipids have been associated with the pathogenesis of insulin resistance. More recently, sphingosine 1-phosphate (S1P), another bioactive sphingolipid derivative, has also been shown to increase in T2D and obesity. Although many studies propose a protective role of S1P metabolism on insulin signaling in peripheral tissues, other studies suggest a causal role of S1P on insulin resistance. In this review, we critically summarize the current state of knowledge of S1P metabolism and its modulating role on insulin resistance. A particular emphasis is placed on S1P and insulin signaling in hepatocytes, skeletal muscle cells, adipocytes and pancreatic 13-cells. In particular, modulation of receptors and enzymes that regulate S1P metabolism can be considered as a new therapeutic option for the treatment of insulin resistance and T2D.
Despite their overt focus on inexplicable alien forces, cosmic horror stories are also determined by their human cast. Far from being merely fodder for horror, the characters significantly contribute to the generation of meaning, including that of the supernatural entity or phenomenon itself. The same holds for the narrators' (implicitly) political perspectives on the world of which they are part. Much of the perspective propounded in Lovecraft's cosmic horror stories partakes of myth, adopting in particular the latter's universal view and pronounced sidelining of humanity as a whole, which it intensifies to the point of horror. Appearances to the contrary notwithstanding, this universal perspective is consistent with the racism permeating and structuring Lovecraft's writing. Though eschewing racism and universalism, the cosmic horror of Kiernan's "Tidal Forces" negotiates literary reflections of colonialism from an unreflective white perspective.
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.
Process-based integrated assessment models (IAMs) project long-term transformation pathways in energy and land-use systems under what-if assumptions. IAM evaluation is necessary to improve the models’ usefulness as scientific tools applicable in the complex and contested domain of climate change mitigation. We contribute the first comprehensive synthesis of process-based IAM evaluation research, drawing on a wide range of examples across six different evaluation methods including historical simulations, stylised facts, and model diagnostics. For each evaluation method, we identify progress and milestones to date, and draw out lessons learnt as well as challenges remaining. We find that each evaluation method has distinctive strengths, as well as constraints on its application. We use these insights to propose a systematic evaluation framework combining multiple methods to establish the appropriateness, interpretability, credibility, and relevance of process-based IAMs as useful scientific tools for informing climate policy. We also set out a programme of evaluation research to be mainstreamed both within and outside the IAM community.
Background: Being an essential trace element, copper is involved in diverse physiological processes. However, excess levels might lead to adverse effects. Disrupted copper homeostasis, particularly in the brain, has been associated with human diseases including the neurodegenerative disorders Wilson and Alzheimer?s disease. In this context, astrocytes play an important role in the regulation of the copper homeostasis in the brain and likely in the prevention against neuronal toxicity, consequently pointing them out as a potential target for the neurotoxicity of copper. Major toxic mechanisms are discussed to be directed against mitochondria probably via oxidative stress. However, the toxic potential and mode of action of copper in astrocytes is poorly understood, so far. Methods: In this study, excess copper levels affecting human astrocytic cell model and their involvement in the neurotoxic mode of action of copper, as well as, effects on the homeostasis of other trace elements (Mn, Fe, Ca and Mg) were investigated. Results: Copper induced substantial cytotoxic effects in the human astrocytic cell line following 48 h incubation (EC30: 250 ?M) and affected mitochondrial function, as observed via reduction of mitochondrial membrane potential and increased ROS production, likely originating from mitochondria. Moreover, cellular GSH metabolism was altered as well. Interestingly, not only cellular copper levels were affected, but also the homeostasis of other elements (Ca, Fe and Mn) were disrupted. Conclusion: One potential toxic mode of action of copper seems to be effects on the mitochondria along with induction of oxidative stress in the human astrocytic cell model. Moreover, excess copper levels seem to interact with the homeostasis of other essential elements such as Ca, Fe and Mn. Disrupted element homeostasis might also contribute to the induction of oxidative stress, likely involved in the onset and progression of neurodegenerative disorders. These insights in the toxic mechanisms will help to develop ideas and approaches for therapeutic strategies against copper-mediated diseases.
Secretory Wnt trafficking can be studied in the polarized epithelial monolayer of Drosophila wing imaginal discs (WID). In this tissue, Wg (Drosophila Wnt-I) is presented on the apical surface of its source cells before being internalized into the endosomal pathway. Long-range Wg secretion and spread depend on secondary secretion from endosomal compartments, but the exact post-endocytic fate of Wg is poorly understood. Here, we summarize and present three protocols for the immunofluorescencebased visualization and quantitation of different pools of intracellular and extracellular Wg in WID: (1) steady-state extracellular Wg; (2) dynamic Wg trafficking inside endosomal compartments; and (3) dynamic Wg release to the cell surface. Using a genetic driver system for gene manipulation specifically at the posterior part of the WID (EnGal4) provides a robust internal control that allows for direct comparison of signal intensities of control and manipulated compartments of the same WID. Therefore, it also circumvents the high degree of staining variability usually associated with whole-tissue samples. In combination with the genetic manipulation of Wg pathway components that is easily feasible in Drosophila, these methods provide a tool-set for the dissection of secretory Wg trafficking and can help us to understand how Wnt proteins travel along endosomal compartments for short-and long-range signal secretion.
The response of the hydrogen molecular ion, H-2(+), to few-cycle laser pulses of different intensities is simulated. To treat the coupled electron-nuclear motion, we use adiabatic potentials computed with Gaussian-type basis sets together with a heuristic ionization model for the electron and a grid representation for the nuclei. Using this mixed-basis approach, the time-dependent Schrodinger equation is solved, either within the Born-Oppenheimer approximation or with nonadiabatic couplings included. The dipole response spectra are compared to all-grid-based solutions for the three-body problem, which we take as a reference to benchmark the Gaussian-type basis set approaches. Also, calculations employing the fixed-nuclei approximation are performed, to quantify effects due to nuclear motion. For low intensities and small ionization probabilities, we get excellent agreement of the dynamics using Gaussian-type basis sets with the all-grid solutions. Our investigations suggest that high harmonic generation (HHG) and high-frequency response, in general, can be reliably modeled using Gaussian-type basis sets for the electrons for not too high harmonics. Further, nuclear motion destroys electronic coherences in the response spectra even on the time scale of about 30 fs and affects HHG intensities, which reflect the electron dynamics occurring on the attosecond time scale. For the present system, non-Born-Oppenheimer effects are small. The Gaussian-based, nonadiabatically coupled, time-dependent multisurface approach to treat quantum electron-nuclear motion beyond the non-Born-Oppenheimer approximation can be easily extended to approximate wavefunction methods, such as time-dependent configuration interaction singles (TD-CIS), for systems where no benchmarks are available.
Ausgehend von der Teilung in nichtaktive (Haushalt) und aktive Bevölkerung (Markt) fragt der Beitrag nach der Rolle, die statistische Vergleichsverfahren bei dieser Grenzziehung in der Welt der Arbeit spielen. Dies geschieht vor dem Hintergrund der Verzweigung von zwei strukturellen Entwicklungen, nämlich dem Wandel der (Arbeits‑)Welten und der statistischen Vergleichsverfahren. Der Beitrag gehört zu den ersten, der diese Nahtstelle systematisch und empirisch an der nationalen und internationalen (Beschäftigungs‑)Statistik untersucht. In diesem Beitrag schlage ich vor, die beiden Beobachtungsebenen als ein Feld der inter/nationalen Statistik zu verstehen. Ihre Ähnlichkeiten, Unterschiede und Verzweigungen werden soziologisch bislang noch nicht wahrgenommen. Im Unterschied dazu behandele ich sie aus einer wissensgeschichtlichen und wissenssoziologischen Perspektive gemeinsam hinsichtlich ihrer Selektionsleistungen, Beobachtungsinstrumente und Beschreibungsebenen. Die Ergebnisse zeigen die zunehmende Spezifizierung und Ausdehnung der ökonomischen Dimension von Arbeitstätigkeiten, die durch die Ordnungstechniken der inter/nationalen Statistik, verstärkt nach 1945, forciert werden. Diese Verschiebungen, so das Argument, sind eng mit dem Aufstieg des technischen Wissens im „technical internationalism“ verbunden, die nach 1945 das statistische und das Alltagsverständnis von der wirtschaftlich nichtaktiven Haushaltsarbeit bekräftigen.
The scapula plays a significant role in efficient shoulder movement. Thus, alterations from typical scapular motion during upper limb movements are thought to be associated with shoulder pathologies. However, a clear understanding of the relationship is not yet obtained.. Scapular alterations may only represent physiological variability as their occurrence can appear equally as frequent in individuals with and without shoulder disorders. Evaluation of scapular motion during increased load might be a beneficial approach to detect clinically relevant alterations. However, functional motion adaptations in response to maximum effort upper extremity loading has not been established yet. Therefore, the overall purpose of this research project was to give further insight in physiological adaptations of scapular kinematics and their underlying scapular muscle activity in response to high demanding shoulder movements in healthy asymptomatic individuals. Prior to the investigation of the effect of various load situation, the reproducibility of scapular kinematics and scapular muscle activity were evaluated under maximum effort arm movements. Healthy asymptomatic adults performed unloaded and maximal loaded concentric and eccentric isokinetic shoulder flexion and extension movements in the scapular plane while scapular kinematics and scapular muscle activity were simultaneously assessed. A 3D motion capture system (infra-red cameras & reflective markers) was utilized to track scapular and humerus motion in relation to the thorax. 3D scapular position angles were given for arm raising and lowering between humerus positions of 20° and 120° flexion. To further characterize the scapular pattern, the scapular motion extent and scapulohumeral rhythm (ratio of scapular and humerus motion extent) were determined. Muscle activity of the upper and lower trapezius and the serratus anterior were assessed with surface electromyography. Amplitudes were calculated for the whole ROM and four equidistant movement phases. Reliability was characterized by overall moderate to good reproducibility across the load conditions. Irrespective of applied load, scapular kinematics followed a motion pattern of continuous upward rotation, posterior tilt and external rotation during arm elevation and a continuous downward rotation, anterior tilt and internal rotation during arm lowering. However, kinematics were altered between maximal loaded and unloaded conditions showing increased upward rotation, reduced posterior tilt and external rotation. Further, the scapulohumeral rhythm was decreased and scapular motion extent increased under maximal loaded movements. Muscle activity during maximum effort were of greater magnitude and differed in their pattern in comparison to the continuous increase and decrease of activity during unloaded shoulder flexion and extension. Relationships between scapular kinematics and their underlying scapular muscle activity could only be identified for a few isolated combinations, whereas the majority showed no associations. Scapular kinematics and scapular muscle activity pattern alter according to the applied load. Alterations between the load conditions comply in magnitude and partially in direction with differences seen between symptomatic and asymptomatic individuals. Even though long-term effects of identified adaptations in response to maximum load are so far unclear, deviations from typical scapular motion or muscle activation should not per se be seen as indicators of shoulder impairment. However, evaluation of alterations in scapular motion and activation in response to maximum effort may have the potential to identify individuals that are unable to cope with increased upper limb demands. Findings further challenge the understanding of scapular motion and stabilization by the trapezius and serratus anterior muscles, as clear relationships between the underlying scapular muscle activity and scapular kinematics were neither observed during unloaded nor maximal loaded shoulder movements.
Characterization of scapular kinematics under demanding load conditions might aid to distinguish between physiological and clinically relevant alterations. Previous investigations focused only on submaximal external load situations. How scapular movement changes with maximal load remains unclear. Therefore, the present study aimed to evaluate 3D scapular kinematics during unloaded and maximal loaded shoulder flexion and extension. Twelve asymptomatic individuals performed shoulder flexion and extension movements under unloaded and maximal concentric and eccentric loaded isokinetic conditions. 3D scapular kinematics assessed with a motion capture system was analyzed for 20° intervals of humeral positions from 20° to 120° flexion. Repeated measures ANOVAs were used to evaluate kinematic differences between load conditions for scapular position angles, scapulohumeral rhythm and scapular motion extent. Increased scapular upward rotation was seen during shoulder flexion and extension as well as decreased posterior tilt and external rotation during eccentric and concentric arm descents of maximal loaded compared to unloaded conditions. Load effects were further seen for the scapulohumeral rhythm with greater scapular involvement at lower humeral positions and increased scapular motion extent under maximal loaded shoulder movements. With maximal load applied to the arm physiological scapular movement pattern are induced that may imply both impingement sparing and causing mechanisms.
Biodiversity decline causes a loss of functional diversity, which threatens ecosystems through a dangerous feedback loop: This loss may hamper ecosystems’ ability to buffer environmental changes, leading to further biodiversity losses. In this context, the increasing frequency of human-induced excessive loading of nutrients causes major problems in aquatic systems. Previous studies investigating how functional diversity influences the response of food webs to disturbances have mainly considered systems with at most two functionally diverse trophic levels. We investigated the effects of functional diversity on the robustness, that is, resistance, resilience, and elasticity, using a tritrophic—and thus more realistic—plankton food web model. We compared a non-adaptive food chain with no diversity within the individual trophic levels to a more diverse food web with three adaptive trophic levels. The species fitness differences were balanced through trade-offs between defense/growth rate for prey and selectivity/half-saturation constant for predators. We showed that the resistance, resilience, and elasticity of tritrophic food webs decreased with larger perturbation sizes and depended on the state of the system when the perturbation occurred. Importantly, we found that a more diverse food web was generally more resistant and resilient but its elasticity was context-dependent. Particularly, functional diversity reduced the probability of a regime shift toward a non-desirable alternative state. The basal-intermediate interaction consistently determined the robustness against a nutrient pulse despite the complex influence of the shape and type of the dynamical attractors. This relationship was strongly influenced by the diversity present and the third trophic level. Overall, using a food web model of realistic complexity, this study confirms the destructive potential of the positive feedback loop between biodiversity loss and robustness, by uncovering mechanisms leading to a decrease in resistance, resilience, and potentially elasticity as functional diversity declines.
The use of acidic ionic liquids and solids as electrolytes in fuel cells is an emerging field due to their efficient proton conductivity and good thermal stability. Despite multiple reports describing conducting properties of acidic ILs, little is known on the charge-transport mechanism in the vicinity of liquid-glass transition and the structural factors governing the proton hopping. To address these issues, we studied two acidic imidazolium-based ILs with the same cation, however, different anions-bulk tosylate vs small methanesulfonate. High-pressure dielectric studies of anhydrous and water-saturated materials performed in the close vicinity of T-g have revealed significant differences in the charge-transport mechanism in these two systems being undetectable at ambient conditions. Thereby, we demonstrated the effect of molecular architecture on proton hopping, being crucial in the potential electrochemical applications of acidic ILs.
Introduction
(2021)
Exendin-4 is a pharmaceutical peptide used in the control of insulin secretion. Structural information on exendin-4 and related peptides especially on the level of quaternary structure is scarce. We present the first published association equilibria of exendin-4 directly measured by static and dynamic light scattering. We show that exendin-4 oligomerization is pH dependent and that these oligomers are of low compactness. We relate our experimental results to a structural hypothesis to describe molecular details of exendin-4 oligomers. Discussion of the validity of this hypothesis is based on NMR, circular dichroism and fluorescence spectroscopy, and light scattering data on exendin-4 and a set of exendin-4 derived peptides. The essential forces driving oligomerization of exendin-4 are helix–helix interactions and interactions of a conserved hydrophobic moiety. Our structural hypothesis suggests that key interactions of exendin-4 monomers in the experimentally supported trimer take place between a defined helical segment and a hydrophobic triangle constituted by the Phe22 residues of the three monomeric subunits. Our data rationalize that Val19 might function as an anchor in the N-terminus of the interacting helix-region and that Trp25 is partially shielded in the oligomer by C-terminal amino acids of the same monomer. Our structural hypothesis suggests that the Trp25 residues do not interact with each other, but with C-terminal Pro residues of their own monomers.
Phase equilibria that are relevant for the growth of Bi2MO4 have been studied experimentally, and the ternary phase diagrams of Bi2O3-PdO2-Pd and Bi2O3-Cu2O-CuO and its isopleth section Bi2O3-CuO were redetermined. It is shown that every melting and crystallization process is always accompanied by a redox process at the phase boundary and that for both title compounds, the valence of the transition metal is lowered during melting. Vice versa, during crystal growth, O-2 must be transported through the melt to the phase boundary. Based on these new insights provided by our thermodynamic studies, Bi2CuO4 single crystals with a length of up to 7 cm and a diameter of 6 mm were grown by the OFZ technique to be used for investigations of magnetic, electronic and thermal transport properties. The grown crystals were characterized by powder X-ray diffraction, Laue, magnetization and specific heat measurements.