TY - JOUR
A1 - Grebenkov, Denis S.
A1 - Metzler, Ralf
A1 - Oshanin, Gleb
T1 - A molecular relay race: sequential first-passage events to the terminal reaction centre in a cascade of diffusion controlled processes
JF - New Journal of Physics (NJP)
N2 - We consider a sequential cascade of molecular first-reaction events towards a terminal reaction centre in which each reaction step is controlled by diffusive motion of the particles. The model studied here represents a typical reaction setting encountered in diverse molecular biology systems, in which, e.g. a signal transduction proceeds via a series of consecutive 'messengers': the first messenger has to find its respective immobile target site triggering a launch of the second messenger, the second messenger seeks its own target site and provokes a launch of the third messenger and so on, resembling a relay race in human competitions. For such a molecular relay race taking place in infinite one-, two- and three-dimensional systems, we find exact expressions for the probability density function of the time instant of the terminal reaction event, conditioned on preceding successful reaction events on an ordered array of target sites. The obtained expressions pertain to the most general conditions: number of intermediate stages and the corresponding diffusion coefficients, the sizes of the target sites, the distances between them, as well as their reactivities are arbitrary.
KW - diffusion
KW - reaction cascade
KW - first passage time
Y1 - 2021
U6 - https://doi.org/10.1088/1367-2630/ac1e42
SN - 1367-2630
VL - 23
PB - IOP - Institute of Physics Publishing
CY - Bristol
ER -
TY - JOUR
A1 - Pornsawad, Pornsarp
A1 - Sapsakul, Nantawan
A1 - Böckmann, Christine
T1 - A modified asymptotical regularization of nonlinear ill-posed problems
JF - Mathematics
N2 - In this paper, we investigate the continuous version of modified iterative Runge–Kutta-type methods for nonlinear inverse ill-posed problems proposed in a previous work. The convergence analysis is proved under the tangential cone condition, a modified discrepancy principle, i.e., the stopping time T is a solution of ∥𝐹(𝑥𝛿(𝑇))−𝑦𝛿∥=𝜏𝛿+ for some 𝛿+>𝛿, and an appropriate source condition. We yield the optimal rate of convergence.
KW - nonlinear operator
KW - regularization
KW - discrepancy principle
KW - asymptotic method
KW - optimal rate
Y1 - 2019
U6 - https://doi.org/10.3390/math7050419
SN - 2227-7390
VL - 7
PB - MDPI
CY - Basel, Schweiz
ET - 5
ER -
TY - JOUR
A1 - Hassanin, Alshaimaa
A1 - Kliem, Bernhard
A1 - Seehafer, Norbert
A1 - Török, Tibor
T1 - A model of homologous confined and ejective eruptions involving kink instability and flux cancellation
JF - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2 - In this study, we model a sequence of a confined and a full eruption, employing the relaxed end state of the confined eruption of a kink-unstable flux rope as the initial condition for the ejective one. The full eruption, a model of a coronal mass ejection, develops as a result of converging motions imposed at the photospheric boundary, which drive flux cancellation. In this process, parts of the positive and negative external flux converge toward the polarity inversion line, reconnect, and cancel each other. Flux of the same amount as the canceled flux transfers to a flux rope, increasing the free magnetic energy of the coronal field. With sustained flux cancellation and the associated progressive weakening of the magnetic tension of the overlying flux, we find that a flux reduction of approximate to 11% initiates the torus instability of the flux rope, which leads to a full eruption. These results demonstrate that a homologous full eruption, following a confined one, can be driven by flux cancellation.
Y1 - 2022
U6 - https://doi.org/10.3847/2041-8213/ac64a9
SN - 2041-8205
SN - 2041-8213
VL - 929
IS - 2
PB - IOP Publ. Ltd.
CY - Bristol
ER -
TY - JOUR
A1 - Ramezani Ziarani, Maryam
A1 - Bookhagen, Bodo
A1 - Schmidt, Torsten
A1 - Wickert, Jens
A1 - de la Torre, Alejandro
A1 - Deng, Zhiguo
A1 - Calori, Andrea
T1 - A model for the relationship between rainfall, GNSS-derived integrated water vapour, and CAPE in the eastern central Andes
JF - Remote Sensing
N2 - Atmospheric water vapour content is a key variable that controls the development of deep convective storms and rainfall extremes over the central Andes. Direct measurements of water vapour are challenging; however, recent developments in microwave processing allow the use of phase delays from L-band radar to measure the water vapour content throughout the atmosphere: Global Navigation Satellite System (GNSS)-based integrated water vapour (IWV) monitoring shows promising results to measure vertically integrated water vapour at high temporal resolutions. Previous works also identified convective available potential energy (CAPE) as a key climatic variable for the formation of deep convective storms and rainfall in the central Andes. Our analysis relies on GNSS data from the Argentine Continuous Satellite Monitoring Network, Red Argentina de Monitoreo Satelital Continuo (RAMSAC) network from 1999 to 2013. CAPE is derived from version 2.0 of the ECMWF’s (European Centre for Medium-Range Weather Forecasts) Re-Analysis (ERA-interim) and rainfall from the TRMM (Tropical Rainfall Measuring Mission) product. In this study, we first analyse the rainfall characteristics of two GNSS-IWV stations by comparing their complementary cumulative distribution function (CCDF). Second, we separately derive the relation between rainfall vs. CAPE and GNSS-IWV. Based on our distribution fitting analysis, we observe an exponential relation of rainfall to GNSS-IWV. In contrast, we report a power-law relationship between the daily mean value of rainfall and CAPE at the GNSS-IWV station locations in the eastern central Andes that is close to the theoretical relationship based on parcel theory. Third, we generate a joint regression model through a multivariable regression analysis using CAPE and GNSS-IWV to explain the contribution of both variables in the presence of each other to extreme rainfall during the austral summer season. We found that rainfall can be characterised with a higher statistical significance for higher rainfall quantiles, e.g., the 0.9 quantile based on goodness-of-fit criterion for quantile regression. We observed different contributions of CAPE and GNSS-IWV to rainfall for each station for the 0.9 quantile. Fourth, we identify the temporal relation between extreme rainfall (the 90th, 95th, and 99th percentiles) and both GNSS-IWV and CAPE at 6 h time steps. We observed an increase before the rainfall event and at the time of peak rainfall—both for GNSS-integrated water vapour and CAPE. We show higher values of CAPE and GNSS-IWV for higher rainfall percentiles (99th and 95th percentiles) compared to the 90th percentile at a 6-h temporal scale. Based on our correlation analyses and the dynamics of the time series, we show that both GNSS-IWV and CAPE had comparable magnitudes, and we argue to consider both climatic variables when investigating their effect on rainfall extremes.
KW - Global Navigation Satellite System (GNSS)
KW - GNSS-integrated water vapour
KW - convective available potential energy (CAPE)
KW - extreme rainfall
KW - TRMM
Y1 - 2021
U6 - https://doi.org/10.3390/rs13183788
SN - 2072-4292
VL - 13
IS - 18
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Staubitz, Thomas
A1 - Serth, Sebastian
A1 - Thomas, Max
A1 - Ebner, Martin
A1 - Koschutnig-Ebner, Markus
A1 - Rampelt, Florian
A1 - von Stetten, Alexander
A1 - Wittke, Andreas
ED - Meinel, Christoph
ED - Schweiger, Stefanie
ED - Staubitz, Thomas
ED - Conrad, Robert
ED - Alario Hoyos, Carlos
ED - Ebner, Martin
ED - Sancassani, Susanna
ED - Żur, Agnieszka
ED - Friedl, Christian
ED - Halawa, Sherif
ED - Gamage, Dilrukshi
ED - Scott, Jeffrey
ED - Kristine Jonson Carlon, May
ED - Deville, Yves
ED - Gaebel, Michael
ED - Delgado Kloos, Carlos
ED - von Schmieden, Karen
T1 - A metastandard for the international exchange of MOOCs
BT - the MOOChub as first prototype
JF - EMOOCs 2023 : Post-Covid Prospects for Massive Open Online Courses - Boost or Backlash?
N2 - The MOOChub is a joined web-based catalog of all relevant German and Austrian MOOC platforms that lists well over 750 Massive Open Online Courses (MOOCs). Automatically building such a catalog requires that all partners describe and publicly offer the metadata of their courses in the same way. The paper at hand presents the genesis of the idea to establish a common metadata standard and the story of its subsequent development. The result of this effort is, first, an open-licensed de-facto-standard, which is based on existing commonly used standards and second, a first prototypical platform that is using this standard: the MOOChub, which lists all courses of the involved partners. This catalog is searchable and provides a more comprehensive overview of basically all MOOCs that are offered by German and Austrian MOOC platforms. Finally, the upcoming developments to further optimize the catalog and the metadata standard are reported.
KW - Digitale Bildung
KW - Kursdesign
KW - MOOC
KW - Micro Degree
KW - Online-Lehre
KW - Onlinekurs
KW - Onlinekurs-Produktion
KW - digital education
KW - e-learning
KW - micro degree
KW - micro-credential
KW - online course creation
KW - online course design
KW - online teaching
Y1 - 2023
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-624154
SP - 147
EP - 161
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - Schiro, Gabriele
A1 - Colangeli, Pierluigi
A1 - Müller, Marina E. H.
T1 - A Metabarcoding Analysis of the Mycobiome of Wheat Ears Across a Topographically Heterogeneous Field
JF - Frontiers in microbiology
KW - Fusarium
KW - microclimate
KW - canopy
KW - fungal community
KW - Alternaria
KW - spatially induced variance
Y1 - 2019
U6 - https://doi.org/10.3389/fmicb.2019.02095
SN - 1664-302X
VL - 10
PB - Frontiers Research Foundation
CY - Lausanne
ER -
TY - JOUR
A1 - Hartung, Niklas
A1 - Borghardt, Jens Markus
T1 - A mechanistic framework for a priori pharmacokinetic predictions of orally inhaled drugs
JF - PLoS Computational Biology : a new community journal
N2 - Author summary
The use of orally inhaled drugs for treating lung diseases is appealing since they have the potential for lung selectivity, i.e. high exposure at the site of action -the lung- without excessive side effects. However, the degree of lung selectivity depends on a large number of factors, including physiochemical properties of drug molecules, patient disease state, and inhalation devices. To predict the impact of these factors on drug exposure and thereby to understand the characteristics of an optimal drug for inhalation, we develop a predictive mathematical framework (a "pharmacokinetic model"). In contrast to previous approaches, our model allows combining knowledge from different sources appropriately and its predictions were able to adequately predict different sets of clinical data. Finally, we compare the impact of different factors and find that the most important factors are the size of the inhaled particles, the affinity of the drug to the lung tissue, as well as the rate of drug dissolution in the lung. In contrast to the common belief, the solubility of a drug in the lining fluids is not found to be relevant. These findings are important to understand how inhaled drugs should be designed to achieve best treatment results in patients.
The fate of orally inhaled drugs is determined by pulmonary pharmacokinetic processes such as particle deposition, pulmonary drug dissolution, and mucociliary clearance. Even though each single process has been systematically investigated, a quantitative understanding on the interaction of processes remains limited and therefore identifying optimal drug and formulation characteristics for orally inhaled drugs is still challenging. To investigate this complex interplay, the pulmonary processes can be integrated into mathematical models. However, existing modeling attempts considerably simplify these processes or are not systematically evaluated against (clinical) data. In this work, we developed a mathematical framework based on physiologically-structured population equations to integrate all relevant pulmonary processes mechanistically. A tailored numerical resolution strategy was chosen and the mechanistic model was evaluated systematically against data from different clinical studies. Without adapting the mechanistic model or estimating kinetic parameters based on individual study data, the developed model was able to predict simultaneously (i) lung retention profiles of inhaled insoluble particles, (ii) particle size-dependent pharmacokinetics of inhaled monodisperse particles, (iii) pharmacokinetic differences between inhaled fluticasone propionate and budesonide, as well as (iv) pharmacokinetic differences between healthy volunteers and asthmatic patients. Finally, to identify the most impactful optimization criteria for orally inhaled drugs, the developed mechanistic model was applied to investigate the impact of input parameters on both the pulmonary and systemic exposure. Interestingly, the solubility of the inhaled drug did not have any relevant impact on the local and systemic pharmacokinetics. Instead, the pulmonary dissolution rate, the particle size, the tissue affinity, and the systemic clearance were the most impactful potential optimization parameters. In the future, the developed prediction framework should be considered a powerful tool for identifying optimal drug and formulation characteristics.
Y1 - 2020
U6 - https://doi.org/10.1371/journal.pcbi.1008466
SN - 1553-734X
SN - 1553-7358
VL - 16
IS - 12
PB - PLoS
CY - San Fransisco
ER -
TY - JOUR
A1 - Wandt, Viktoria Klara Veronika
A1 - Winkelbeiner, Nicola Lisa
A1 - Bornhorst, Julia
A1 - Witt, Barbara
A1 - Raschke, Stefanie
A1 - Simon, Luise
A1 - Ebert, Franziska
A1 - Kipp, Anna Patricia
A1 - Schwerdtle, Tanja
T1 - A matter of concern
BT - trace element dyshomeostasis and genomic stability in neurons
JF - Redox Biology
N2 - 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
Y1 - 2021
U6 - https://doi.org/10.1016/j.redox.2021.101877
SN - 2213-2317
VL - 41
PB - Elsevier
CY - Amsterdam
ER -
TY - JOUR
A1 - Malem-Shinitski, Noa
A1 - Opper, Manfred
A1 - Reich, Sebastian
A1 - Schwetlick, Lisa
A1 - Seelig, Stefan A.
A1 - Engbert, Ralf
T1 - A mathematical model of local and global attention in natural scene viewing
JF - PLoS Computational Biology : a new community journal
N2 - Author summary
Switching between local and global attention is a general strategy in human information processing. We investigate whether this strategy is a viable approach to model sequences of fixations generated by a human observer in a free viewing task with natural scenes. Variants of the basic model are used to predict the experimental data based on Bayesian inference. Results indicate a high predictive power for both aggregated data and individual differences across observers. The combination of a novel model with state-of-the-art Bayesian methods lends support to our two-state model using local and global internal attention states for controlling eye movements.
Understanding the decision process underlying gaze control is an important question in cognitive neuroscience with applications in diverse fields ranging from psychology to computer vision. The decision for choosing an upcoming saccade target can be framed as a selection process between two states: Should the observer further inspect the information near the current gaze position (local attention) or continue with exploration of other patches of the given scene (global attention)? Here we propose and investigate a mathematical model motivated by switching between these two attentional states during scene viewing. The model is derived from a minimal set of assumptions that generates realistic eye movement behavior. We implemented a Bayesian approach for model parameter inference based on the model's likelihood function. In order to simplify the inference, we applied data augmentation methods that allowed the use of conjugate priors and the construction of an efficient Gibbs sampler. This approach turned out to be numerically efficient and permitted fitting interindividual differences in saccade statistics. Thus, the main contribution of our modeling approach is two-fold; first, we propose a new model for saccade generation in scene viewing. Second, we demonstrate the use of novel methods from Bayesian inference in the field of scan path modeling.
Y1 - 2020
U6 - https://doi.org/10.1371/journal.pcbi.1007880
SN - 1553-734X
SN - 1553-7358
VL - 16
IS - 12
PB - PLoS
CY - San Fransisco
ER -
TY - JOUR
A1 - Fuchs, Susanne
A1 - Koenig, Laura L.
A1 - Gerstenberg, Annette
T1 - A longitudinal study of speech acoustics in older French females
BT - analysis of the filler particle euh across utterance positions
JF - Languages : open access journal
N2 - Aging in speech production is a multidimensional process. Biological, cognitive, social, and communicative factors can change over time, stay relatively stable, or may even compensate for each other. In this longitudinal work, we focus on stability and change at the laryngeal and supralaryngeal levels in the discourse particle euh produced by 10 older French-speaking females at two times, 10 years apart. Recognizing the multiple discourse roles of euh, we divided out occurrences according to utterance position. We quantified the frequency of euh, and evaluated acoustic changes in formants, fundamental frequency, and voice quality across time and utterance position. Results showed that euh frequency was stable with age. The only acoustic measure that revealed an age effect was harmonics-to-noise ratio, showing less noise at older ages. Other measures mostly varied with utterance position, sometimes in interaction with age. Some voice quality changes could reflect laryngeal adjustments that provide for airflow conservation utterance-finally. The data suggest that aging effects may be evident in some prosodic positions (e.g., utterance-final position), but not others (utterance-initial position). Thus, it is essential to consider the interactions among these factors in future work and not assume that vocal aging is evident throughout the signal.
KW - aging
KW - prosody
KW - voice quality
KW - fundamental frequency
KW - formants
KW - filler
KW - particles
Y1 - 2021
U6 - https://doi.org/10.3390/languages6040211
SN - 2226-471X
VL - 6
IS - 4
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Herold, Fabian
A1 - Labott, Berit K.
A1 - Grässler, Bernhard
A1 - Halfpaap, Nicole
A1 - Langhans, Corinna
A1 - Müller, Patrick
A1 - Ammar, Achraf
A1 - Dordevic, Milos
A1 - Hökelmann, Anita
A1 - Müller, Notger Germar
T1 - A Link between Handgrip Strength and Executive Functioning: A Cross-Sectional Study in Older Adults with Mild Cognitive Impairment and Healthy Controls
JF - Healthcare : open access journal
N2 - Older adults with amnestic mild cognitive impairment (aMCI) who in addition to their memory deficits also suffer from frontal-executive dysfunctions have a higher risk of developing dementia later in their lives than older adults with aMCI without executive deficits and older adults with non-amnestic MCI (naMCI). Handgrip strength (HGS) is also correlated with the risk of cognitive decline in the elderly. Hence, the current study aimed to investigate the associations between HGS and executive functioning in individuals with aMCI, naMCI and healthy controls. Older, right-handed adults with amnestic MCI (aMCI), non-amnestic MCI (naMCI), and healthy controls (HC) conducted a handgrip strength measurement via a handheld dynamometer. Executive functions were assessed with the Trail Making Test (TMT A&B). Normalized handgrip strength (nHGS, normalized to Body Mass Index (BMI)) was calculated and its associations with executive functions (operationalized through z-scores of TMT B/A ratio) were investigated through partial correlation analyses (i.e., accounting for age, sex, and severity of depressive symptoms). A positive and low-to-moderate correlation between right nHGS (rp (22) = 0.364; p = 0.063) and left nHGS (rp (22) = 0.420; p = 0.037) and executive functioning in older adults with aMCI but not in naMCI or HC was observed. Our results suggest that higher levels of nHGS are linked to better executive functioning in aMCI but not naMCI and HC. This relationship is perhaps driven by alterations in the integrity of the hippocampal-prefrontal network occurring in older adults with aMCI. Further research is needed to provide empirical evidence for this assumption.
KW - MCI
KW - hippocampal-prefrontal network
KW - handgrip strength
KW - exercise cognition
KW - aging
KW - brain health
Y1 - 2022
U6 - https://doi.org/10.3390/healthcare10020230
SN - 2227-9032
VL - 10
SP - 1
EP - 14
PB - MDPI
CY - Basel, Schweiz
ET - 2
ER -
TY - JOUR
A1 - Schwarz, Ingo
A1 - Kutzinski, Vera M.
ED - Ette, Ottmar
ED - Knobloch, Eberhard
T1 - A Letter from Alexander von Humboldt to Joseph Albert Wright – Archival Traces
JF - HiN : Alexander von Humboldt im Netz
N2 - A few months before his death, A. v. Humboldt attended the celebration in honor of the 127th birthday of George Washington at the US legation in Berlin. A letter to the American Envoy, Joseph A. Wright (1810 – 1867), underlines Humboldt’s admiration for the fi rst president of the United States. At the same time Humboldt asked the diplomat to mail a letter to the German-American Bernard Moses (1832 – 1897) in Clinton, Louisiana, who had named his son Alexander Humboldt Moses (grave on the Hebrew Rest Cemetery #2 in New Orleans, burial plot A, 12, 5). It appears to be possible that the Moses family still owns Humboldt’s letter.
N2 - Wenige Monate vor seinem Tod besuchte A. v. Humboldt die Feier zu Ehren des 127. Geburtstages von George Washington an der Gesandtschaft der Vereinigten Staaten in Berlin. Ein Brief an den Gesandten, Joseph A. Wright (1810 – 1867), betonte Humboldts Bewunderung für den ersten Präsidenten der Vereinten Staaten. Gleichzeit bat Humboldt den Diplomaten um die Beförderung eines Briefes an den Deutschamerikaner Bernard Moses(1832 – 1897) in Clinton, Louisiana, der seinen Sohn Alexander Humboldt Moses (Grab auf dem Hebrew Rest Cemetery #2 in New Orleans, Grabstelle A, 12, 5) genannt hat.
N2 - Unos meses antes de su muerte, A. v. Humboldt asistió a la celebración en honor al 127º cumpleaños de George Washington en la legación estadounidense en Berlín. Una carta al delegado estadounidense, Joseph A. Wright (1810 – 1867), subraya la admiración de Humboldt por el primer presidente de los Estados Unidos. Al mismo tiempo, Humboldt le pidió al diplomático que enviara una carta al germano-estadounidense Bernard Moses (1832 – 1897) en Clinton, Louisiana, quien había puesto a su hijo, el nombre de Alexander Humboldt Moses(tumba en el cementerio Hebrew Rest número 2 en Nueva Orleans, lugar de enteramiento: A, 12, 5).
KW - Alexander Humboldt
KW - Moses
KW - Korrespondenz Alexander von Humboldts
KW - Vereinigten Staaten
Y1 - 2021
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-532787
SN - 2568-3543
SN - 1617-5239
VL - XXII
IS - 43
SP - 5
EP - 12
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - Zhang, Youjun
A1 - Chen, Moxian
A1 - Siemiatkowska, Beata
A1 - Toleco, Mitchell Rey
A1 - Jing, Yue
A1 - Strotmann, Vivien
A1 - Zhang, Jianghua
A1 - Stahl, Yvonne
A1 - Fernie, Alisdair
T1 - A highly efficient agrobacterium-mediated method for transient gene expression and functional studies in multiple plant species
JF - Plant Communications
N2 - Although the use of stable transformation technology has led to great insight into gene function, its application in high-throughput studies remains arduous. Agro-infiltration have been widely used in species such as Nicotiana benthamiana for the rapid detection of gene expression and protein interaction analysis, but this technique does not work efficiently in other plant species, including Arabidopsis thaliana. As an efficient high-throughput transient expression system is currently lacking in the model plant species A. thaliana, we developed a method that is characterized by high efficiency, reproducibility, and suitability for transient expression of a variety of functional proteins in A. thaliana and 7 other plant species, including Brassica oleracea, Capsella rubella, Thellungiella salsuginea, Thellungiella halophila, Solanum tuberosum, Capsicum annuum, and N. benthamiana. Efficiency of this method was independently verified in three independent research facilities, pointing to the robustness of this technique. Furthermore, in addition to demonstrating the utility of this technique in a range of species, we also present a case study employing this method to assess protein-protein interactions in the sucrose biosynthesis pathway in Arabidopsis.
KW - transient expression
KW - agro-infiltration
KW - subcellular localization
KW - protein-protein interaction
Y1 - 2019
SN - 2590-3462
VL - 1
IS - 5
PB - Science Direct
CY - New York
ER -
TY - JOUR
A1 - Zass, Alexander
T1 - A Gibbs point process of diffusions: Existence and uniqueness
JF - Lectures in pure and applied mathematics
KW - random point processes
KW - statistical mechanics
KW - stochastic analysis
Y1 - 2020
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-471951
SN - 978-3-86956-485-2
SN - 2199-4951
SN - 2199-496X
IS - 6
SP - 13
EP - 22
PB - Universitätsverlag Potsdam
CY - Potsdam
ER -
TY - JOUR
A1 - Risbey, James S.
A1 - Lewandowsky, Stephan
A1 - Cowtan, Kevin
A1 - Oreskes, Naomi
A1 - Rahmstorf, Stefan
A1 - Jokimäki, Ari
A1 - Foster, Grant
T1 - A fluctuation in surface temperature in historical context
BT - reassessment and retrospective on the evidence
JF - Environmental research letters
N2 - This work reviews the literature on an alleged global warming 'pause' in global mean surface temperature (GMST) to determine how it has been defined, what time intervals are used to characterise it, what data are used to measure it, and what methods used to assess it. We test for 'pauses', both in the normally understood meaning of the term to mean no warming trend, as well as for a 'pause' defined as a substantially slower trend in GMST. The tests are carried out with the historical versions of GMST that existed for each pause-interval tested, and with current versions of each of the GMST datasets. The tests are conducted following the common (but questionable) practice of breaking the linear fit at the start of the trend interval ('broken' trends), and also with trends that are continuous with the data bordering the trend interval. We also compare results when appropriate allowance is made for the selection bias problem. The results show that there is little or no statistical evidence for a lack of trend or slower trend in GMST using either the historical data or the current data. The perception that there was a 'pause' in GMST was bolstered by earlier biases in the data in combination with incomplete statistical testing.
KW - climate variability
KW - climate trends
KW - temperature fluctuation
KW - pause hiatus
Y1 - 2018
U6 - https://doi.org/10.1088/1748-9326/aaf342
SN - 1748-9326
VL - 13
IS - 12
PB - IOP Publ. Ltd.
CY - Bristol
ER -
TY - JOUR
A1 - Langenhan, Jennifer
A1 - Jaeger, Carsten
A1 - Baum, Katharina
A1 - Simon, Mareike
A1 - Lisec, Jan
T1 - A flexible tool to correct superimposed mass isotopologue distributions in GC-APCI-MS flux experiments
JF - Metabolites
N2 - The investigation of metabolic fluxes and metabolite distributions within cells by means of tracer molecules is a valuable tool to unravel the complexity of biological systems. Technological advances in mass spectrometry (MS) technology such as atmospheric pressure chemical ionization (APCI) coupled with high resolution (HR), not only allows for highly sensitive analyses but also broadens the usefulness of tracer-based experiments, as interesting signals can be annotated de novo when not yet present in a compound library. However, several effects in the APCI ion source, i.e., fragmentation and rearrangement, lead to superimposed mass isotopologue distributions (MID) within the mass spectra, which need to be corrected during data evaluation as they will impair enrichment calculation otherwise. Here, we present and evaluate a novel software tool to automatically perform such corrections. We discuss the different effects, explain the implemented algorithm, and show its application on several experimental datasets. This adjustable tool is available as an R package from CRAN.
KW - mass isotopologue distribution
KW - enrichment calculation
KW - flux
KW - experiments
KW - atmospheric pressure chemical ionization
KW - R package
KW - CorMID
Y1 - 2022
U6 - https://doi.org/10.3390/metabo12050408
SN - 2218-1989
VL - 12
IS - 5
PB - MDPI
CY - Basel
ER -
TY - JOUR
A1 - Xiao, Shangbin
A1 - Liu, Liu
A1 - Wang, Wei
A1 - Lorke, Andreas
A1 - Woodhouse, Jason Nicholas
A1 - Grossart, Hans-Peter
T1 - A Fast-Response Automated Gas Equilibrator (FaRAGE) for continuous in situ measurement of CH4 and CO2 dissolved in water
JF - Hydrology and earth system sciences : HESS
N2 - Biogenic greenhouse gas emissions, e.g., of methane (CH4) and carbon dioxide (CO2) from inland waters, contribute substantially to global warming. In aquatic systems, dissolved greenhouse gases are highly heterogeneous in both space and time. To better understand the biological and physical processes that affect sources and sinks of both CH4 and CO2, their dissolved concentrations need to be measured with high spatial and temporal resolution. To achieve this goal, we developed the Fast-Response Automated Gas Equilibrator (FaRAGE) for real-time in situ measurement of dissolved CH4 and CO2 concentrations at the water surface and in the water column. FaRAGE can achieve an exceptionally short response time (t(95%) = 12 s when including the response time of the gas analyzer) while retaining an equilibration ratio of 62.6% and a measurement accuracy of 0.5% for CH4. A similar performance was observed for dissolved CO2 (t(95%) = 10 s, equilibration ratio 67.1 %). An equilibration ratio as high as 91.8% can be reached at the cost of a slightly increased response time (16 s). The FaRAGE is capable of continuously measuring dissolved CO2 and CH4 concentrations in the nM-to-submM (10(-9)-10(-3) mol L-1) range with a detection limit of subnM (10(-10) mol L-1), when coupling with a cavity ring-down greenhouse gas analyzer (Picarro GasScouter). FaRAGE allows for the possibility of mapping dissolved concentration in a "quasi" three-dimensional manner in lakes and provides an inexpensive alternative to other commercial gas equilibrators. It is simple to operate and suitable for continuous monitoring with a strong tolerance for suspended particles. While the FaRAGE is developed for inland waters, it can be also applied to ocean waters by tuning the gas-water mixing ratio. The FaRAGE is easily adapted to suit other gas analyzers expanding the range of potential applications, including nitrous oxide and isotopic composition of the gases.
Y1 - 2020
U6 - https://doi.org/10.5194/hess-24-3871-2020
SN - 1027-5606
SN - 1607-7938
VL - 24
IS - 7
SP - 3871
EP - 3880
PB - European Geosciences Union (EGU) ; Copernicus
CY - Munich
ER -
TY - JOUR
A1 - Demal, Till Joscha
A1 - Heise, Melina
A1 - Reiz, Benedikt
A1 - Dogra, Deepika
A1 - Braenne, Ingrid
A1 - Reichenspurner, Hermann
A1 - Männer, Jörg
A1 - Aherrahrou, Zouhair
A1 - Schunkert, Heribert
A1 - Erdmann, Jeanette
A1 - Abdelilah-Seyfried, Salim
T1 - A familial congenital heart disease with a possible multigenic origin involving a mutation in BMPR1A
JF - Scientific reports
N2 - The genetics of many congenital heart diseases (CHDs) can only unsatisfactorily be explained by known chromosomal or Mendelian syndromes. Here, we present sequencing data of a family with a potentially multigenic origin of CHD. Twelve of nineteen family members carry a familial mutation [NM_004329.2:c.1328 G > A (p.R443H)] which encodes a predicted deleterious variant of BMPR1A. This mutation co-segregates with a linkage region on chromosome 1 that associates with the emergence of severe CHDs including Ebstein’s anomaly, atrioventricular septal defect, and others. We show that the continuous overexpression of the zebrafish homologous mutation bmpr1aap.R438H within endocardium causes a reduced AV valve area, a downregulation of Wnt/ß-catenin signalling at the AV canal, and growth of additional tissue mass in adult zebrafish hearts. This finding opens the possibility of testing genetic interactions between BMPR1A and other candidate genes within linkage region 1 which may provide a first step towards unravelling more complex genetic patterns in cardiovascular disease aetiology.
Y1 - 2019
U6 - https://doi.org/10.1038/s41598-019-39648-7
SN - 2045-2322
VL - 9
PB - Nature Publ. Group
CY - London
ER -
TY - JOUR
A1 - Ette, Ottmar
T1 - A expulsão do Éden
BT - Migração e escrita depois do paraíso
JF - Literatura e autoritarismo
N2 - A temática da migração está intimamente vinculada à história humana, desde a narrativa bíblica da expulsão do paraíso. O ser humano não apenas empregou técnicas cada vez mais sofisticadas para a violência, como também transmitiu, através dos séculos, técnicas de conservação e uso de seu saberconviver. Nesse sentido móvel da história, e em consonância com as literaturas do mundo, a partir de suas diversas origens, é possível dizer que existe um “Homo migrans” desde que existe o “Homo sapiens”. Assim, é possível afirmar que as ideias territoriais ou territorializantes com proveniência histórico-espacial permitem, vez ou outra, reconhecer seus esforços para filtrar e isolar a dimensão histórico-móvel e vetorial da história como narrativa, para tentar construir, com a ajuda de ideias estáticas, novos lugares da promessa ou da perda, da abundância ou da queda.
KW - Migração
KW - Saberconviver
KW - Literaturas do mundo
Y1 - 2021
U6 - https://doi.org/10.5902/1679849X65745
SN - 1679-849X
IS - 25
SP - 5
EP - 42
PB - Universidade Federal de Santa Maria (UFSM)
CY - Santa Maria
ER -
TY - JOUR
A1 - Brill, Fabio Alexander
A1 - Passuni Pineda, Silvia
A1 - Espichan Cuya, Bruno
A1 - Kreibich, Heidi
T1 - A data-mining approach towards damage modelling for El Nino events in Peru
JF - Geomatics, natural hazards and risk
N2 - Compound natural hazards likeEl Ninoevents cause high damage to society, which to manage requires reliable risk assessments. Damage modelling is a prerequisite for quantitative risk estimations, yet many procedures still rely on expert knowledge, and empirical studies investigating damage from compound natural hazards hardly exist. A nationwide building survey in Peru after theEl Ninoevent 2017 - which caused intense rainfall, ponding water, flash floods and landslides - enables us to apply data-mining methods for statistical groundwork, using explanatory features generated from remote sensing products and open data. We separate regions of different dominant characteristics through unsupervised clustering, and investigate feature importance rankings for classifying damage via supervised machine learning. Besides the expected effect of precipitation, the classification algorithms select the topographic wetness index as most important feature, especially in low elevation areas. The slope length and steepness factor ranks high for mountains and canyons. Partial dependence plots further hint at amplified vulnerability in rural areas. An example of an empirical damage probability map, developed with a random forest model, is provided to demonstrate the technical feasibility.
KW - Natural hazard
KW - damage model
KW - residential buildings
KW - data-mining
KW - remote
KW - sensing
KW - open data
Y1 - 2020
U6 - https://doi.org/10.1080/19475705.2020.1818636
SN - 1947-5705
SN - 1947-5713
VL - 11
IS - 1
SP - 1966
EP - 1990
PB - Routledge, Taylor & Francis Group
CY - Abingdon
ER -