TY  - JOUR
A1  - Albrecht, Torsten
A1  - Winkelmann, Ricarda
A1  - Levermann, Anders
T1  - Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)
BT  - Part 1: boundary conditions and climatic forcing
JF  - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2  - Simulations of the glacial-interglacial history of the Antarctic Ice Sheet provide insights into dynamic threshold behavior and estimates of the ice sheet's contributions to global sea-level changes for the past, present and future. However, boundary conditions are weakly constrained, in particular at the interface of the ice sheet and the bedrock. Also climatic forcing covering the last glacial cycles is uncertain, as it is based on sparse proxy data. <br /> We use the Parallel Ice Sheet Model (PISM) to investigate the dynamic effects of different choices of input data, e.g., for modern basal heat flux or reconstructions of past changes of sea level and surface temperature. As computational resources are limited, glacial-cycle simulations are performed using a comparably coarse model grid of 16 km and various parameterizations, e.g., for basal sliding, iceberg calving, or for past variations in precipitation and ocean temperatures. In this study we evaluate the model's transient sensitivity to corresponding parameter choices and to different boundary conditions over the last two glacial cycles and provide estimates of involved uncertainties. We also discuss isolated and combined effects of climate and sea-level forcing. Hence, this study serves as a "cookbook" for the growing community of PISM users and paleo-ice sheet modelers in general. <br /> For each of the different model uncertainties with regard to climatic forcing, ice and Earth dynamics, and basal processes, we select one representative model parameter that captures relevant uncertainties and motivates corresponding parameter ranges that bound the observed ice volume at present. The four selected parameters are systematically varied in a parameter ensemble analysis, which is described in a companion paper.
Y1  - 2020
U6  - https://doi.org/10.5194/tc-14-599-2020
SN  - 1994-0416
SN  - 1994-0424
VL  - 14
IS  - 2
SP  - 599
EP  - 632
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Kreuzer, Moritz
A1  - Reese, Ronja
A1  - Huiskamp, Willem Nicholas
A1  - Petri, Stefan
A1  - Albrecht, Torsten
A1  - Feulner, Georg
A1  - Winkelmann, Ricarda
T1  - Coupling framework (1.0) for the PISM (1.1.4) ice sheet model and the MOMS (5.1.0) ocean model via the PICO ice shelf cavity model in an Antarctic domain
JF  - Geoscientific model development : an interactive open access journal of the European Geosciences Union
N2  - The past and future evolution of the Antarctic Ice Sheet is largely controlled by interactions between the ocean and floating ice shelves. To investigate these interactions, coupled ocean and ice sheet model configurations are required. Previous modelling studies have mostly relied on high-resolution configurations, limiting these studies to individual glaciers or regions over short timescales of decades to a few centuries. We present a framework to couple the dynamic ice sheet model PISM (Parallel Ice Sheet Model) with the global ocean general circulation model MOM5 (Modular Ocean Model) via the ice shelf cavity model PICO (Pots-dam Ice-shelf Cavity mOdel). As ice shelf cavities are not resolved by MOM5 but are parameterized with the PICO box model, the framework allows the ice sheet and ocean components to be run at resolutions of 16 km and 3 degrees respectively. This approach makes the coupled configuration a useful tool for the analysis of interactions between the Antarctic Ice Sheet and the global ocean over time spans of the order of centuries to millennia. In this study, we describe the technical implementation of this coupling framework: sub-shelf melting in the ice sheet component is calculated by PICO from modelled ocean temperatures and salinities at the depth of the continental shelf, and, vice versa, the resulting mass and energy fluxes from melting at the ice-ocean interface are transferred to the ocean component. Mass and energy fluxes are shown to be conserved to machine precision across the considered component domains. The implementation is computationally efficient as it introduces only minimal overhead. Furthermore, the coupled model is evaluated in a 4000 year simulation under constant present-day climate forcing and is found to be stable with respect to the ocean and ice sheet spin-up states. The framework deals with heterogeneous spatial grid geometries, varying grid resolutions, and timescales between the ice and ocean component in a generic way; thus, it can be adopted to a wide range of model set-ups.
Y1  - 2021
U6  - https://doi.org/10.5194/gmd-14-3697-2021
SN  - 1991-959X
SN  - 1991-9603
VL  - 14
IS  - 6
SP  - 3697
EP  - 3714
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Zeitz, Maria
A1  - Haacker, Jan M.
A1  - Donges, Jonathan
A1  - Albrecht, Torsten
A1  - Winkelmann, Ricarda
T1  - Dynamic regimes of the Greenland Ice Sheet emerging from interacting melt-elevation and glacial isostatic adjustment feedbacks
JF  - Earth system dynamics
N2  - The stability of the Greenland Ice Sheet under global warming is governed by a number of dynamic processes and interacting feedback mechanisms in the ice sheet, atmosphere and solid Earth. 
Here we study the long-term effects due to the interplay of the competing melt-elevation and glacial isostatic adjustment (GIA) feedbacks for different temperature step forcing experiments with a coupled ice-sheet and solid-Earth model. 
Our model results show that for warming levels above 2 degrees C, Greenland could become essentially ice-free within several millennia, mainly as a result of surface melting and acceleration of ice flow. These ice losses are mitigated, however, in some cases with strong GIA feedback even promoting an incomplete recovery of the Greenland ice volume. We further explore the full-factorial parameter space determining the relative strengths of the two feedbacks: our findings suggest distinct dynamic regimes of the Greenland Ice Sheets on the route to destabilization under global warming - from incomplete recovery, via quasi-periodic oscillations in ice volume to ice-sheet collapse. 
In the incomplete recovery regime, the initial ice loss due to warming is essentially reversed within 50 000 years, and the ice volume stabilizes at 61 %-93 % of the present-day volume. For certain combinations of temperature increase, atmospheric lapse rate and mantle viscosity, the interaction of the GIA feedback and the melt-elevation feedback leads to self-sustained, long-term oscillations in ice-sheet volume with oscillation periods between 74 000 and over 300 000 years and oscillation amplitudes between 15 %-70 % of present-day ice volume. 
This oscillatory regime reveals a possible mode of internal climatic variability in the Earth system on timescales on the order of 100 000 years that may be excited by or synchronized with orbital forcing or interact with glacial cycles and other slow modes of variability. Our findings are not meant as scenario-based near-term projections of ice losses but rather providing insight into of the feedback loops governing the "deep future" and, thus, long-term resilience of the Greenland Ice Sheet.
Y1  - 2022
U6  - https://doi.org/10.5194/esd-13-1077-2022
SN  - 2190-4979
SN  - 2190-4987
VL  - 13
IS  - 3
SP  - 1077
EP  - 1096
PB  - Copernicus Publ.
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Albrecht, Torsten
A1  - Winkelmann, Ricarda
A1  - Levermann, Anders
T1  - Glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM)
BT  - part 2: parameter ensemble analysis
JF  - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2  - The Parallel Ice Sheet Model (PISM) is applied to the Antarctic Ice Sheet over the last two glacial cycles (approximate to 210 000 years) with a resolution of 16 km. An ensemble of 256 model runs is analyzed in which four relevant model parameters have been systematically varied using full-factorial parameter sampling. Parameters and plausible parameter ranges have been identified in a companion paper (Albrecht et al., 2020) and are associated with ice dynamics, climatic forcing, basal sliding and bed deformation and represent distinct classes of model uncertainties. The model is scored against both modern and geologic data, including reconstructed grounding-line locations, elevation-age data, ice thickness, surface velocities and uplift rates. An aggregated score is computed for each ensemble member that measures the overall model-data misfit, including measurement uncertainty in terms of a Gaussian error model (Briggs and Tarasov, 2013). The statistical method used to analyze the ensemble simulation results follows closely the simple averaging method described in Pollard et al. (2016). 
This analysis reveals clusters of best-fit parameter combinations, and hence a likely range of relevant model and boundary parameters, rather than individual best-fit parameters. The ensemble of reconstructed histories of Antarctic Ice Sheet volumes provides a score-weighted likely range of sea-level contributions since the Last Glacial Maximum (LGM) of 9.4 +/- 4.1m (or 6.5 +/- 2.0 x 10(6) km(3)), which is at the upper range of most previous studies. The last deglaciation occurs in all ensemble simulations after around 12 000 years before present and hence after the meltwater pulse 1A (MWP1a). Our ensemble analysis also provides an estimate of parametric uncertainty bounds for the present-day state that can be used for PISM projections of future sea-level contributions from the Antarctic Ice Sheet.
Y1  - 2020
U6  - https://doi.org/10.5194/tc-14-633-2020
SN  - 1994-0416
SN  - 1994-0424
VL  - 14
IS  - 2
SP  - 633
EP  - 656
PB  - Copernicus Publ.
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Schlemm, Tanja
A1  - Feldmann, Johannes
A1  - Winkelmann, Ricarda
A1  - Levermann, Anders
T1  - Stabilizing effect of melange buttressing on the marine ice-cliff instability of the West Antarctic Ice Sheet
JF  - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2  - Owing to global warming and particularly high regional ocean warming, both Thwaites and Pine Island Glaciers in the Amundsen region of the Antarctic Ice Sheet could lose their buttressing ice shelves over time. We analyse the possible consequences using the parallel ice sheet model (PISM), applying a simple cliff-calving parameterization and an ice melange-buttressing model. We find that the instantaneous loss of ice-shelf buttressing, due to enforced ice-shelf melting, initiates grounding-line retreat and triggers marine ice sheet instability (MISI). As a consequence, the grounding line progresses into the interior of the West Antarctic Ice Sheet and leads to a sea level contribution of 0.6 m within 100 a. By subjecting the exposed ice cliffs to cliff calving using our simplified parameterization, we also analyse marine ice cliff instability (MICI). In our simulations it can double or even triple the sea level contribution depending on the only loosely constrained parameter that determines the maximum cliff-calving rate. The speed of MICI depends on this upper bound of the calving rate, which is given by the ice melange buttressing the glacier. However, stabilization of MICI may occur for geometric reasons. Because the embayment geometry changes as MICI advances into the interior of the ice sheet, the upper bound on calving rates is reduced and the progress of MICI is slowed down. Although we cannot claim that our simulations bear relevant quantitative estimates of the effect of ice-melange buttressing on MICI, the mechanism has the potential to stop the instability. Further research is needed to evaluate its role for the past and future evolution of the Antarctic Ice Sheet.
Y1  - 2022
U6  - https://doi.org/10.5194/tc-16-1979-2022
SN  - 1994-0416
SN  - 1994-0424
VL  - 16
IS  - 5
SP  - 1979
EP  - 1996
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Feldmann, Johannes
A1  - Reese, Ronja
A1  - Winkelmann, Ricarda
A1  - Levermann, Anders
T1  - Shear-margin melting causes stronger transient ice discharge than ice-stream melting in idealized simulations
JF  - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2  - Basal ice-shelf melting is the key driver of Antarctica's increasing sea-level contribution. In diminishing the buttressing force of the ice shelves that fringe the ice sheet, the melting increases the ice discharge into the ocean.
Here we contrast the influence of basal melting in two different ice-shelf regions on the time-dependent response of an isothermal, inherently buttressed ice-sheet-shelf system. In the idealized numerical simulations, the basal-melt perturbations are applied close to the grounding line in the ice-shelf's (1) ice-stream region, where the ice shelf is fed by the fastest ice masses that stream through the upstream bed trough and (2) shear margins, where the ice flow is slower.
The results show that melting below one or both of the shear margins can cause a decadal to centennial increase in ice discharge that is more than twice as large compared to a similar perturbation in the ice-stream region. We attribute this to the fact that melt-induced ice-shelf thinning in the central grounding-line region is attenuated very effectively by the fast flow of the central ice stream. In contrast, the much slower ice dynamics in the lateral shear margins of the ice shelf facilitate sustained ice-shelf thinning and thereby foster buttressing reduction.
Regardless of the melt location, a higher melt concentration toward the grounding line generally goes along with a stronger response. Our results highlight the vulnerability of outlet glaciers to basal melting in stagnant, buttressing-relevant ice-shelf regions, a mechanism that may gain importance under future global warming.
Y1  - 2022
U6  - https://doi.org/10.5194/tc-16-1927-2022
SN  - 1994-0416
SN  - 1994-0424
VL  - 16
IS  - 5
SP  - 1927
EP  - 1940
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Wunderling, Nico
A1  - Willeit, Matteo
A1  - Donges, Jonathan
A1  - Winkelmann, Ricarda
T1  - Global warming due to loss of large ice masses and Arctic summer sea ice
JF  - Nature Communications
N2  - Several large-scale cryosphere elements such as the Arctic summer sea ice, the mountain glaciers, the Greenland and West Antarctic Ice Sheet have changed substantially during the last century due to anthropogenic global warming. However, the impacts of their possible future disintegration on global mean temperature (GMT) and climate feedbacks have not yet been comprehensively evaluated. Here, we quantify this response using an Earth system model of intermediate complexity. Overall, we find a median additional global warming of 0.43 degrees C (interquartile range: 0.39-0.46 degrees C) at a CO2 concentration of 400 ppm. Most of this response (55%) is caused by albedo changes, but lapse rate together with water vapour (30%) and cloud feedbacks (15%) also contribute significantly. While a decay of the ice sheets would occur on centennial to millennial time scales, the Arctic might become ice-free during summer within the 21st century. Our findings imply an additional increase of the GMT on intermediate to long time scales. The disintegration of cryosphere elements such as the Arctic summer sea ice, mountain glaciers, Greenland and West Antarctica is associated with temperature and radiative feedbacks. In this work, the authors quantify these feedbacks and find an additional global warming of 0.43 degrees C.
Y1  - 2020
U6  - https://doi.org/10.1038/s41467-020-18934-3
SN  - 2041-1723
VL  - 11
IS  - 1
PB  - Nature Publishing Group
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Zeitz, Maria
A1  - Reese, Ronja
A1  - Beckmann, Johanna
A1  - Krebs-Kanzow, Uta
A1  - Winkelmann, Ricarda
T1  - Impact of the melt-albedo feedback on the future evolution of the Greenland Ice Sheet with PISM-dEBM-simple
JF  - The Cryosphere : TC ; an interactive open access journal of the European Geosciences Union
N2  - Surface melting of the Greenland Ice Sheet contributes a large amount to current and future sea level rise. Increased surface melt may lower the reflectivity of the ice sheet surface and thereby increase melt rates: the so-called melt-albedo feedback describes this self-sustaining increase in surface melting. In order to test the effect of the melt-albedo feedback in a prognostic ice sheet model, we implement dEBM-simple, a simplified version of the diurnal Energy Balance Model dEBM, in the Parallel Ice Sheet Model (PISM). The implementation includes a simple representation of the melt-albedo feedback and can thereby replace the positive-degree-day melt scheme. Using PISM-dEBM-simple, we find that this feedback increases ice loss through surface warming by 60 % until 2300 for the high-emission scenario RCP8.5 when compared to a scenario in which the albedo remains constant at its present-day values. With an increase of 90 % compared to a fixed-albedo scenario, the effect is more pronounced for lower surface warming under RCP2.6. Furthermore, assuming an immediate darkening of the ice surface over all summer months, we estimate an upper bound for this effect to be 70 % in the RCP8.5 scenario and a more than 4-fold increase under RCP2.6. With dEBM-simple implemented in PISM, we find that the melt-albedo feedback is an essential contributor to mass loss in dynamic simulations of the Greenland Ice Sheet under future warming.
Y1  - 2021
U6  - https://doi.org/10.5194/tc-15-5739-2021
SN  - 1994-0416
SN  - 1994-0424
VL  - 15
IS  - 12
SP  - 5739
EP  - 5764
PB  - Copernicus
CY  - Katlenburg-Lindau
ER  - 
TY  - JOUR
A1  - Klose, Ann Kristin
A1  - Wunderling, Nico
A1  - Winkelmann, Ricarda
A1  - Donges, Jonathan
T1  - What do we mean, 'tipping cascade'?
JF  - Environmental research letters : ERL
N2  - Based on suggested interactions of potential tipping elements in the Earth's climate and in ecological systems, tipping cascades as possible dynamics are increasingly discussed and studied. The activation of such tipping cascades would impose a considerable risk for human societies and biosphere integrity. However, there are ambiguities in the description of tipping cascades within the literature so far. Here we illustrate how different patterns of multiple tipping dynamics emerge from a very simple coupling of two previously studied idealized tipping elements. In particular, we distinguish between a two phase cascade, a domino cascade and a joint cascade. A mitigation of an unfolding two phase cascade may be possible and common early warning indicators are sensitive to upcoming critical transitions to a certain degree. In contrast, a domino cascade may hardly be stopped once initiated and critical slowing down-based indicators fail to indicate tipping of the following element. These different potentials for intervention and anticipation across the distinct patterns of multiple tipping dynamics should be seen as a call to be more precise in future analyses of cascading dynamics arising from tipping element interactions in the Earth system.
KW  - tipping cascade
KW  - domino effect
KW  - tipping interactions
KW  - cascading regime
KW  - shifts
KW  - early warning indicators
Y1  - 2021
U6  - https://doi.org/10.1088/1748-9326/ac3955
SN  - 1748-9326
VL  - 16
IS  - 12
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Tiberius, Victor
A1  - Weyland, Michael
T1  - Identifying constituent elements of entrepreneurship curricula
BT  - a systematic literature review
JF  - Administrative sciences
N2  - Entrepreneurship education research has a strong “output” focus on impact studies but pays much less attention to the “inside” or process perspective of the way entrepreneurship education occurs. In particular, the scattered previous entrepreneurship curriculum research has not managed to provide a current and comprehensive overview of the curricular elements that constitute entrepreneurship education. To overcome this shortcoming, we aim to identify the teaching objectives, teaching contents, teaching methods, and assessment methods discussed in entrepreneurship curriculum research. To this end, we conducted a systematic literature review on the four entrepreneurship curriculum dimensions and collected all mentioned curriculum items. We used a two-stage coding procedure to find the genuinely entrepreneurship-specific items. Among numerous items (also from business management and other subjects), we found 26 objectives, 34 contents, 11 teaching methods, and 7 assessment methods that were entrepreneurship-specific. Most of these items were addressed by only a few scholarly papers.
KW  - assessment methods
KW  - curriculum
KW  - entrepreneurship education
KW  - teaching contents
KW  - teaching methods
KW  - teaching objectives
Y1  - 2023
U6  - https://doi.org/10.3390/admsci14010001
SN  - 2076-3387
VL  - 14
IS  - 1
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Romero Barbosa, Luís
A1  - Coelho, Victor Hugo R.
A1  - Scheiffele, Lena
A1  - Baroni, Gabriele
A1  - Ramos Filho, Geraldo M.
A1  - Montenegro, Suzana M. G. L.
A1  - Das Neves Almeida, Cristiano
A1  - Oswald, Sascha
T1  - Dynamic groundwater recharge simulations based on cosmic-ray neutron sensing in a tropical wet experimental basin
JF  - Vadose zone journal : VZJ : advancing critical zone science
N2  - Although cosmic-ray neutron sensing (CRNS) is probably the most promising noninvasive proximal soil moisture measurement technique at the field scale, its application for hydrological simulations remains underexplored in the literature so far. This study assessed the use of CRNS to inversely calibrate soil hydraulic parameters at the intermediate field scale to simulate the groundwater recharge rates at a daily timescale. The study was conducted for two contrasting hydrological years at the Guaraira experimental basin, Brazil, a 5.84-km(2), a tropical wet and rather flat landscape covered by secondary Atlantic forest. As a consequence of the low altitude and proximity to the equator low neutron count rates could be expected, reducing the precision of CRNS while constituting unexplored and challenging conditions for CRNS applications. Inverse calibration for groundwater recharge rates was used based on CRNS or point-scale soil moisture data. The CRNS-derived retention curve and saturated hydraulic conductivity were consistent with the literature and locally performed slug tests. Simulated groundwater recharge rates ranged from 60 to 470 mm yr(-1), corresponding to 5 and 29% of rainfall, and correlated well with estimates based on water table fluctuations. In contrast, the estimated results based on inversive point-scale datasets were not in alignment with measured water table fluctuations. The better performance of CRNS-based estimations of field-scale hydrological variables, especially groundwater recharge, demonstrated its clear advantages over traditional invasive point-scale techniques. Finally, the study proved the ability of CRNS as practicable in low altitude, tropical wet areas, thus encouraging its adoption for water resources monitoring and management.
Y1  - 2021
U6  - https://doi.org/10.1002/vzj2.20145
SN  - 1539-1663
VL  - 20
IS  - 4
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Durand, Gael
A1  - van den Broeke, Michiel R.
A1  - Le Cozannet, Goneri
A1  - Edwards, Tamsin L.
A1  - Holland, Paul R.
A1  - Jourdain, Nicolas C.
A1  - Marzeion, Ben
A1  - Mottram, Ruth
A1  - Nicholls, Robert J.
A1  - Pattyn, Frank
A1  - Paul, Frank
A1  - Slangen, Aimee B. A.
A1  - Winkelmann, Ricarda
A1  - Burgard, Clara
A1  - van Calcar, Caroline J.
A1  - Barre, Jean-Baptiste
A1  - Bataille, Amelie
A1  - Chapuis, Anne
T1  - Sea-Level rise: from global perspectives to local services
JF  - Frontiers in Marine Science
N2  - Coastal areas are highly diverse, ecologically rich, regions of key socio-economic activity, and are particularly sensitive to sea-level change. Over most of the 20th century, global mean sea level has risen mainly due to warming and subsequent expansion of the upper ocean layers as well as the melting of glaciers and ice caps. Over the last three decades, increased mass loss of the Greenland and Antarctic ice sheets has also started to contribute significantly to contemporary sea-level rise. The future mass loss of the two ice sheets, which combined represent a sea-level rise potential of similar to 65 m, constitutes the main source of uncertainty in long-term (centennial to millennial) sea-level rise projections. Improved knowledge of the magnitude and rate of future sea-level change is therefore of utmost importance. Moreover, sea level does not change uniformly across the globe and can differ greatly at both regional and local scales. The most appropriate and feasible sea level mitigation and adaptation measures in coastal regions strongly depend on local land use and associated risk aversion. Here, we advocate that addressing the problem of future sea-level rise and its impacts requires (i) bringing together a transdisciplinary scientific community, from climate and cryospheric scientists to coastal impact specialists, and (ii) interacting closely and iteratively with users and local stakeholders to co-design and co-build coastal climate services, including addressing the high-end risks.
KW  - sea-level rise
KW  - Antarctic
KW  - Greenland
KW  - glaciers
KW  - local impact
Y1  - 2022
U6  - https://doi.org/10.3389/fmars.2021.709595
SN  - 2296-7745
VL  - 8
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Zielnica, Krzystof
ED  - Ette, Ottmar
ED  - Knobloch, Eberhard
T1  - Alexander von Humboldt und Polen – zum 150. Jahrestag seiner Reise nach Warschau
BT  - mit einleitenden Worten von Ingo Schwarz
JF  - HiN : Alexander von Humboldt im Netz ; International Review for Humboldtian Studies
N2  - Zuerst erschienen in:
Alexander von Humboldt-Stiftung. Mitteilungen, 5. Jg., Heft 38, Oktober 1980, S. 27–36.
KW  - Verhältnis zu Polen
KW  - Ehrenmitglied der Warschauer Gesellschaft der Freunde der Wissenschaften
KW  - Julian Ursyn Niemcewicz
KW  - Nikolaus I.
KW  - Kaiser von Russland und König von Polen (Kongresspolen)
Y1  - 2024
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-646635
SN  - 2568-3543
SN  - 1617-5239
VL  - XXV
IS  - 48
SP  - 87
EP  - 101
PB  - Universitätsverlag Potsdam
CY  - Potsdam
ER  - 
TY  - GEN
A1  - Moreno-Romero, Jordi
A1  - Probst, Aline V.
A1  - Trindade, Inês
A1  - Kalyanikrishna, 
A1  - Engelhorn, Julia
A1  - Farrona, Sara
T1  - Looking At the Past and Heading to the Future
BT  - Meeting Summary of the 6th European Workshop on Plant Chromatin 2019 in Cologne, Germany
T2  - Frontiers in Plant Science
N2  - In June 2019, more than a hundred plant researchers met in Cologne, Germany, for the 6th European Workshop on Plant Chromatin (EWPC). This conference brought together a highly dynamic community of researchers with the common aim to understand how chromatin organization controls gene expression, development, and plant responses to the environment. New evidence showing how epigenetic states are set, perpetuated, and inherited were presented, and novel data related to the three-dimensional organization of chromatin within the nucleus were discussed. At the level of the nucleosome, its composition by different histone variants and their specialized histone deposition complexes were addressed as well as the mechanisms involved in histone post-translational modifications and their role in gene expression. The keynote lecture on plant DNA methylation by Julie Law (SALK Institute) and the tribute session to Lars Hennig, honoring the memory of one of the founders of the EWPC who contributed to promote the plant chromatin and epigenetic field in Europe, added a very special note to this gathering. In this perspective article we summarize some of the most outstanding data and advances on plant chromatin research presented at this workshop.
KW  - EWPC2019
KW  - chromatin
KW  - epigenetics
KW  - transcription
KW  - nucleus
Y1  - 2020
U6  - https://doi.org/10.3389/fpls.2019.01795
SN  - 1664-462X
VL  - 10
IS  - 1795
SP  - 1
EP  - 12
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - GEN
A1  - Grohmann, Nils-Hendrik
T1  - How to avoid politicised monitoring?
BT  - treaty-design suggestions for a business and human rights framework convention
T2  - Völkerrechtsblog : Der Blog des Arbeitskreis junger Völkerrechtswissenschaftler*innen
Y1  - 2022
UR  - https://voelkerrechtsblog.org/de/how-to-avoid-politicised-monitoring/
U6  - https://doi.org/10.17176/20220623-153108-0
SN  - 2510-2567
PB  - M. Riegner c/o Humboldt-Univ
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Pang, Peter Tsun Ho
A1  - Dietrich, Tim
A1  - Tews, Ingo
A1  - Van Den Broeck, Chris
T1  - Parameter estimation for strong phase transitions in supranuclear matter using gravitational-wave astronomy
JF  - Physical review research
N2  - At supranuclear densities, explored in the core of neutron stars, a strong phase transition from hadronic matter to more exotic forms of matter might be present. To test this hypothesis, binary neutron-star mergers offer a unique possibility to probe matter at densities that we cannot create in any existing terrestrial experiment. In this work, we show that, if present, strong phase transitions can have a measurable imprint on the binary neutron-star coalescence and the emitted gravitational-wave signal. We construct a new parametrization of the supranuclear equation of state that allows us to test for the existence of a strong phase transition and extract its characteristic properties purely from the gravitational-wave signal of the inspiraling neutron stars. We test our approach using a Bayesian inference study simulating 600 signals with three different equations of state and find that for current gravitational-wave detector networks already 12 events might be sufficient to verify the presence of a strong phase transition. Finally, we use our methodology to analyze GW170817 and GW190425 but do not find any indication that a strong phase transition is present at densities probed during the inspiral.
Y1  - 2020
U6  - https://doi.org/10.1103/PhysRevResearch.2.033514
SN  - 2643-1564
VL  - 2
IS  - 3
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Bosch, Sina
A1  - De Cesare, Ilaria
A1  - Demske, Ulrike
A1  - Felser, Claudia
T1  - Word-order variation and coherence in German infinitival complementation
JF  - The journal of comparative Germanic linguistics
N2  - This study provides a synthesis of corpus-based and experimental investigations of word-order preferences in German infinitival complementation. We carried out a systematic analysis of present-day German corpora to establish frequency distributions of different word-order options: extraposition, intraposition, and 'third construction'. We then examined, firstly, whether and to what extent corpus frequencies and processing economy constraints can predict the acceptability of these three word-order variants, and whether subject raising and subject control verbs form clearly distinguishable subclasses of infinitive-embedding verbs in terms of their word-order behaviour. Secondly, our study looks into the issue of coherence by comparing acceptability ratings for monoclausal coherent and biclausal incoherent construals of intraposed infinitives, and by examining whether a biclausal incoherent analysis gives rise to local and/or global processing difficulty. Taken together, our results revealed that (i) whilst the extraposition pattern consistently wins out over all other word-order variants for control verbs, neither frequency nor processing-based approaches to word-order variation can account for the acceptability of low-frequency variants, (ii) there is considerable verb-specific variation regarding word-order preferences both between and within the two sets of raising and control verbs under investigation, and (iii) although monoclausal coherent intraposition is rated above biclausal incoherent intraposition, the latter is not any more difficult to process than the former. Our findings indicate that frequency of occurrence and processing-related constraints interact with idiosyncratic lexical properties of individual verbs in determining German speakers' structural preferences.
KW  - Syntactic variation
KW  - German
KW  - Infinitives
KW  - Corpus linguistics
KW  - Acceptability judgements
KW  - Self-paced reading
Y1  - 2023
U6  - https://doi.org/10.1007/s10828-023-09140-8
SN  - 1572-8552
VL  - 26
IS  - 1
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Bulla, Mattia
A1  - Coughlin, Michael W.
A1  - Dhawan, Suhail
A1  - Dietrich, Tim
T1  - Multi-messenger constraints on the Hubble constant through combination of gravitational waves, gamma-ray bursts and kilonovae from neutron star mergers
JF  - Universe : open access journal
N2  - The simultaneous detection of gravitational waves and light from the binary neutron star merger GW170817 led to independent measurements of distance and redshift, providing a direct estimate of the Hubble constant H-0 that does not rely on a cosmic distance ladder, nor assumes a specific cosmological model. 
By using gravitational waves as "standard sirens", this approach holds promise to arbitrate the existing tension between the H-0 value inferred from the cosmic microwave background and those obtained from local measurements.
However, the known degeneracy in the gravitational-wave analysis between distance and inclination of the source led to a H-0 value from GW170817 that was not precise enough to resolve the existing tension. 
In this review, we summarize recent works exploiting the viewing-angle dependence of the electromagnetic signal, namely the associated short gamma-ray burst and kilonova, to constrain the system inclination and improve on H-0. 
We outline the key ingredients of the different methods, summarize the results obtained in the aftermath of GW170817 and discuss the possible systematics introduced by each of these methods.
KW  - gravitational waves
KW  - stars: neutron
KW  - stars: binaries
KW  - cosmology: cosmological parameters
KW  - cosmology: distance scale
KW  - cosmology: cosmic background radiation
Y1  - 2022
U6  - https://doi.org/10.3390/universe8050289
SN  - 2218-1997
VL  - 8
IS  - 5
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Tiberius, Victor
A1  - Weyland, Michael
T1  - Improving curricula for higher entrepreneurship education
BT  - an international real-time Delphi
JF  - Education sciences
N2  - Existing curricula for entrepreneurship education do not necessarily represent the best way of teaching. How could entrepreneurship curricula be improved? To answer this question, we aim to identify and rank desirable teaching objectives, teaching contents, teaching methods, and assessment methods for higher entrepreneurship education. To this end, we employ an international real-time Delphi study with an expert panel consisting of entrepreneurship education instructors and researchers. The study reveals 17 favorable objectives, 17 items of content, 25 teaching methods, and 15 assessment methods, which are ranked according to their desirability and the group consensus. We contribute to entrepreneurship curriculum research by adding a normative perspective.
KW  - curriculum design
KW  - Delphi study
KW  - entrepreneurship education
Y1  - 2024
U6  - https://doi.org/10.3390/educsci14020130
SN  - 2227-7102
VL  - 14
IS  - 2
SP  - 1
EP  - 17
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Lehmann, Nico
A1  - Kuhn, Yves-Alain
A1  - Keller, Martin
A1  - Aye, Norman
A1  - Herold, Fabian
A1  - Draganski, Bogdan
A1  - Taube, Wolfgang
A1  - Taubert, Marco
T1  - Brain activation during active balancing and its behavioral relevance in younger and older adults
BT  - a functional near-infrared spectroscopy (fNIRS) study
JF  - Frontiers in Aging Neuroscience
N2  - Age-related deterioration of balance control is widely regarded as an important phenomenon influencing quality of life and longevity, such that a more comprehensive understanding of the neural mechanisms underlying this process is warranted.

Specifically, previous studies have reported that older adults typically show higher neural activity during balancing as compared to younger counterparts, but the implications of this finding on balance performance remain largely unclear. 
Using functional near-infrared spectroscopy (fNIRS), differences in the cortical control of balance between healthy younger (n = 27) and older (n = 35) adults were explored. 

More specifically, the association between cortical functional activity and balance performance across and within age groups was investigated. To this end, we measured hemodynamic responses (i.e., changes in oxygenated and deoxygenated hemoglobin) while participants balanced on an unstable device. 
As criterion variables for brain-behavior-correlations, we also assessed postural sway while standing on a free-swinging platform and while balancing on wobble boards with different levels of difficulty. 

We found that older compared to younger participants had higher activity in prefrontal and lower activity in postcentral regions. 
Subsequent robust regression analyses revealed that lower prefrontal brain activity was related to improved balance performance across age groups, indicating that higher activity of the prefrontal cortex during balancing reflects neural inefficiency. 

We also present evidence supporting that age serves as a moderator in the relationship between brain activity and balance, i.e., cortical hemodynamics generally appears to be a more important predictor of balance performance in the older than in the younger. Strikingly, we found that age differences in balance performance are mediated by balancing-induced activation of the superior frontal gyrus, thus suggesting that differential activation of this region reflects a mechanism involved in the aging process of the neural control of balance. 

Our study suggests that differences in functional brain activity between age groups are not a mere by-product of aging, but instead of direct behavioral relevance for balance performance. 
Potential implications of these findings in terms of early detection of fall-prone individuals and intervention strategies targeting balance and healthy aging are discussed.
KW  - aging
KW  - neuroimaging
KW  - functional near-infrared spectroscopy (fNIRS)
KW  - balance
KW  - postural control
KW  - prefrontal cortex
KW  - neural inefficiency
Y1  - 2022
U6  - https://doi.org/10.3389/fnagi.2022.828474
SN  - 1663-4365
VL  - 14
PB  - Frontiers Media
CY  - Lausanne
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  - Spiegel, Thomas J.
T1  - The Scientific Weltanschauung
BT  - (Anti-)Naturalism in Dilthey, Jaspers and Analytic Philosophy
JF  - Journal of Transcendental Philosophy
N2  - Different forms of methodological and ontological naturalism constitute the current near-orthodoxy in analytic philosophy. Many prominent figures have called naturalism a (scientific) image (Sellars, W. 1962. “Philosophy and the Scientific Image of Man.” In Wilfrid Sellars, Science, Perception, Reality, 1–40. Ridgeview Publishing), a Weltanschauung (Loewer, B. 2001. “From Physics to Physicalism.” In Physicalism and its Discontents, edited by C. Gillett, and B. Loewer. Cambridge: Cambridge University Press; Stoljar, D. 2010. Physicalism. Routledge), or even a “philosophical ideology” (Kim, J. 2003. “The American Origins of Philosophical Naturalism.” Journal of Philosophical Research 28: 83–98). This suggests that naturalism is indeed something over-and-above an ordinary philosophical thesis (e.g. in contrast to the justified true belief-theory of knowledge). However, these thinkers fail to tease out the host of implications this idea – naturalism being a worldview – presents. This paper draws on (somewhat underappreciated) remarks of Dilthey and Jaspers on the concept of worldviews (Weltanschauung, Weltbild) in order to demonstrate that naturalism as a worldview is a presuppositional background assumption which is left untouched by arguments against naturalism as a thesis. The concluding plea is (in order to make dialectical progress) to re-organize the existing debate on naturalism in a way that treats naturalism not as a first-order philosophical claim, but rather shifts its focus on naturalism’s status as a worldview.
KW  - naturalism
KW  - ideology
KW  - Dilthey
KW  - Jaspers
KW  - scientific image
KW  - worldview
Y1  - 2021
U6  - https://doi.org/10.1515/jtph-2021-0016
SN  - 2626-8329
SN  - 2626-8310
VL  - 2
IS  - 2
SP  - 259
EP  - 276
PB  - De Gruyter
CY  - Berlin ; Boston
ER  - 
TY  - JOUR
A1  - Wachs, Sebastian
A1  - Wright, Michelle F.
A1  - Sittichai, Ruthaychonnee
A1  - Singh, Ritu
A1  - Biswal, Ramakrishna
A1  - Kim, Eun-mee
A1  - Yang, Soeun
A1  - Gámez-Guadix, Manuel
A1  - Almendros, Carmen
A1  - Flora, Katerina
A1  - Daskalou, Vassiliki
A1  - Maziridou, Evdoxia
T1  - Associations between witnessing and perpetrating online hate in eight countries
BT  - the buffering effects of problem-focused coping
JF  - International Journal of Environmental Research and Public Health
N2  - Online hate is a topic that has received considerable interest lately, as online hate represents a risk to self-determination and peaceful coexistence in societies around the globe. However, not much is known about the explanations for adolescents posting or forwarding hateful online material or how adolescents cope with this newly emerging online risk. Thus, we sought to better understand the relationship between a bystander to and perpetrator of online hate, and the moderating effects of problem-focused coping strategies (e.g., assertive, technical coping) within this relationship. Self-report questionnaires on witnessing and committing online hate and assertive and technical coping were completed by 6829 adolescents between 12 and 18 years of age from eight countries. The results showed that increases in witnessing online hate were positively related to being a perpetrator of online hate. Assertive and technical coping strategies were negatively related with perpetrating online hate. Bystanders of online hate reported fewer instances of perpetrating online hate when they reported higher levels of assertive and technical coping strategies, and more frequent instances of perpetrating online hate when they reported lower levels of assertive and technical coping strategies. In conclusion, our findings suggest that, if effective, prevention and intervention programs that target online hate should consider educating young people about problem-focused coping strategies, self-assertiveness, and media skills. Implications for future research are discussed.
KW  - online hate
KW  - hate speech
KW  - bystander
KW  - perpetrator
KW  - coping strategies
KW  - cyber aggression
Y1  - 2019
U6  - https://doi.org/10.3390/ijerph16203992
SN  - 1660-4601
VL  - 16
IS  - 20
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Balint, Miklos
A1  - Marton, Orsolya
A1  - Schatz, Marlene
A1  - Düring, Rolf-Alexander
A1  - Grossart, Hans-Peter
T1  - Proper experimental design requires randomization/balancing of molecular ecology experiments
JF  - Ecology and evolution
N2  - Properly designed (randomized and/or balanced) experiments are standard in ecological research. Molecular methods are increasingly used in ecology, but studies generally do not report the detailed design of sample processing in the laboratory. This may strongly influence the interpretability of results if the laboratory procedures do not account for the confounding effects of unexpected laboratory events. We demonstrate this with a simple experiment where unexpected differences in laboratory processing of samples would have biased results if randomization in DNA extraction and PCR steps do not provide safeguards. We emphasize the need for proper experimental design and reporting of the laboratory phase of molecular ecology research to ensure the reliability and interpretability of results.
KW  - batch effect
KW  - bias
KW  - DNA extraction
KW  - environmental DNA
KW  - laboratory practice
KW  - lake community
KW  - metabarcoding
KW  - nondemonic intrusions
KW  - PCR
KW  - sediment
Y1  - 2018
U6  - https://doi.org/10.1002/ece3.3687
SN  - 2045-7758
VL  - 8
IS  - 3
SP  - 1786
EP  - 1793
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Bizic-Ionescu, Mina
A1  - Ionescu, Danny
A1  - Grossart, Hans-Peter
T1  - Organic Particles: Heterogeneous Hubs for Microbial Interactions in Aquatic Ecosystems
JF  - Frontiers in microbiology
N2  - The dynamics and activities of microbes colonizing organic particles (hereafter particles) greatly determine the efficiency of the aquatic carbon pump. Current understanding is that particle composition, structure and surface properties, determined mostly by the forming organisms and organic matter, dictate initial microbial colonization and the subsequent rapid succession events taking place as organic matter lability and nutrient content change with microbial degradation. We applied a transcriptomic approach to assess the role of stochastic events on initial microbial colonization of particles. Furthermore, we asked whether gene expression corroborates rapid changes in carbon-quality. Commonly used size fractionated filtration averages thousands of particles of different sizes, sources, and ages. To overcome this drawback, we used replicate samples consisting each of 3–4 particles of identical source and age and further evaluated the consequences of averaging 10–1000s of particles. Using flow-through rolling tanks we conducted long-term experiments at near in situ conditions minimizing the biasing effects of closed incubation approaches often referred to as “the bottle-effect.” In our open flow-through rolling tank system, however, active microbial communities were highly heterogeneous despite an identical particle source, suggesting random initial colonization. Contrasting previous reports using closed incubation systems, expression of carbon utilization genes didn’t change after 1 week of incubation. Consequently, we suggest that in nature, changes in particle-associated community related to carbon availability are much slower (days to weeks) due to constant supply of labile, easily degradable organic matter. Initial, random particle colonization seems to be subsequently altered by multiple organismic interactions shaping microbial community interactions and functional dynamics. Comparative analysis of thousands particles pooled togethers as well as pooled samples suggests that mechanistic studies of microbial dynamics should be done on single particles. The observed microbial heterogeneity and inter-organismic interactions may have important implications for evolution and biogeochemistry in aquatic systems.
KW  - particle-associated bacteria
KW  - microbial communities
KW  - inter- and intra-species interactions
KW  - antagonism
KW  - phage
KW  - transcriptome
Y1  - 2018
U6  - https://doi.org/10.3389/fmicb.2018.02569
SN  - 1664-302X
VL  - 9
PB  - Frontiers Research Foundation
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Wurzbacher, Christian
A1  - Fuchs, Andrea
A1  - Attermeyer, Katrin
A1  - Frindte, Katharina
A1  - Grossart, Hans-Peter
A1  - Hupfer, Michael
A1  - Casper, Peter
A1  - Monaghan, Michael T.
T1  - Shifts among Eukaryota, Bacteria, and Archaea define the vertical organization of a lake sediment
JF  - Microbiome
N2  - Background: Lake sediments harbor diverse microbial communities that cycle carbon and nutrients while being constantly colonized and potentially buried by organic matter sinking from the water column. The interaction of activity and burial remained largely unexplored in aquatic sediments. We aimed to relate taxonomic composition to sediment biogeochemical parameters, test whether community turnover with depth resulted from taxonomic replacement or from richness effects, and to provide a basic model for the vertical community structure in sediments. Methods: We analyzed four replicate sediment cores taken from 30-m depth in oligo-mesotrophic Lake Stechlin in northern Germany. Each 30-cm core spanned ca. 170 years of sediment accumulation according to Cs-137 dating and was sectioned into layers 1-4 cm thick. We examined a full suite of biogeochemical parameters and used DNA metabarcoding to examine community composition of microbial Archaea, Bacteria, and Eukaryota. Results: Community beta-diversity indicated nearly complete turnover within the uppermost 30 cm. We observed a pronounced shift from Eukaryota- and Bacteria-dominated upper layers (<5 cm) to Bacteria-dominated intermediate layers (5-14 cm) and to deep layers (>14 cm) dominated by enigmatic Archaea that typically occur in deep-sea sediments. Taxonomic replacement was the prevalent mechanism in structuring the community composition and was linked to parameters indicative of microbial activity (e.g., CO2 and CH4 concentration, bacterial protein production). Richness loss played a lesser role but was linked to conservative parameters (e.g., C, N, P) indicative of past conditions. Conclusions: By including all three domains, we were able to directly link the exponential decay of eukaryotes with the active sediment microbial community. The dominance of Archaea in deeper layers confirms earlier findings from marine systems and establishes freshwater sediments as a potential low-energy environment, similar to deep sea sediments. We propose a general model of sediment structure and function based on microbial characteristics and burial processes. An upper "replacement horizon" is dominated by rapid taxonomic turnover with depth, high microbial activity, and biotic interactions. A lower "depauperate horizon" is characterized by low taxonomic richness, more stable "low-energy" conditions, and a dominance of enigmatic Archaea.
KW  - Archaea
KW  - Eukaryota
KW  - Bacteria
KW  - Community
KW  - Freshwater
KW  - Lake
KW  - DNA metabarcoding
KW  - Beta-diversity
KW  - Sediment
KW  - Turnover
Y1  - 2017
U6  - https://doi.org/10.1186/s40168-017-0255-9
SN  - 2049-2618
VL  - 5
PB  - BioMed Central
CY  - London
ER  - 
TY  - JOUR
A1  - Göritz, Anna
A1  - Berger, Stella A.
A1  - Gege, Peter
A1  - Grossart, Hans-Peter
A1  - Nejstgaard, Jens C.
A1  - Riedel, Sebastian
A1  - Röttgers, Rüdiger
A1  - Utschig, Christian
T1  - Retrieval of water constituents from hyperspectral in-situ measurements under variable cloud cover
BT  - a case study at Lake Stechlin (Germany)
JF  - Remote sensing / Molecular Diversity Preservation International (MDPI)
N2  - Remote sensing and field spectroscopy of natural waters is typically performed under clear skies, low wind speeds and low solar zenith angles. Such measurements can also be made, in principle, under clouds and mixed skies using airborne or in-situ measurements; however, variable illumination conditions pose a challenge to data analysis. In the present case study, we evaluated the inversion of hyperspectral in-situ measurements for water constituent retrieval acquired under variable cloud cover. First, we studied the retrieval of Chlorophyll-a (Chl-a) concentration and colored dissolved organic matter (CDOM) absorption from in-water irradiance measurements. Then, we evaluated the errors in the retrievals of the concentration of total suspended matter (TSM), Chl-a and the absorption coefficient of CDOM from above-water reflectance measurements due to highly variable reflections at the water surface. In order to approximate cloud reflections, we extended a recent three-component surface reflectance model for cloudless atmospheres by a constant offset and compared different surface reflectance correction procedures. Our findings suggest that in-water irradiance measurements may be used for the analysis of absorbing compounds even under highly variable weather conditions. The extended surface reflectance model proved to contribute to the analysis of above-water reflectance measurements with respect to Chl-a and TSM. Results indicate the potential of this approach for all-weather monitoring.
KW  - remote sensing
KW  - inland water
KW  - hyperspectral measurements
KW  - in-situ
KW  - cloud
KW  - surface reflection
KW  - inversion
KW  - bio-optical modeling
Y1  - 2018
U6  - https://doi.org/10.3390/rs10020181
SN  - 2072-4292
VL  - 10
IS  - 2
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Cuadrat, Rafael R. C.
A1  - Ionescu, Danny
A1  - Davila, Alberto M. R.
A1  - Grossart, Hans-Peter
T1  - Recovering genomics clusters of secondary metabolites from lakes using genome-resolved metagenomics
JF  - Frontiers in microbiology
N2  - Metagenomic approaches became increasingly popular in the past decades due to decreasing costs of DNA sequencing and bioinformatics development. So far, however, the recovery of long genes coding for secondary metabolites still represents a big challenge. Often, the quality of metagenome assemblies is poor, especially in environments with a high microbial diversity where sequence coverage is low and complexity of natural communities high. Recently, new and improved algorithms for binning environmental reads and contigs have been developed to overcome such limitations. Some of these algorithms use a similarity detection approach to classify the obtained reads into taxonomical units and to assemble draft genomes. This approach, however, is quite limited since it can classify exclusively sequences similar to those available (and well classified) in the databases. In this work, we used draft genomes from Lake Stechlin, north-eastern Germany, recovered by MetaBat, an efficient binning tool that integrates empirical probabilistic distances of genome abundance, and tetranucleotide frequency for accurate metagenome binning. These genomes were screened for secondary metabolism genes, such as polyketide synthases (PKS) and non-ribosomal peptide synthases (NRPS), using the Anti-SMASH and NAPDOS workflows. With this approach we were able to identify 243 secondary metabolite clusters from 121 genomes recovered from our lake samples. A total of 18 NRPS, 19 PKS, and 3 hybrid PKS/NRPS clusters were found. In addition, it was possible to predict the partial structure of several secondary metabolite clusters allowing for taxonomical classifications and phylogenetic inferences. Our approach revealed a high potential to recover and study secondary metabolites genes from any aquatic ecosystem.
KW  - metagenomics 2.0
KW  - PKS
KW  - NRPS
KW  - freshwater
KW  - environmental genomics
Y1  - 2018
U6  - https://doi.org/10.3389/fmicb.2018.00251
SN  - 1664-302X
VL  - 9
PB  - Frontiers Research Foundation
CY  - Lausanne
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  - Hoke, Alexa
A1  - Woodhouse, Jason Nicholas
A1  - Zoccarato, Luca
A1  - McCarthy, Valerie
A1  - de Eyto, Elvira
A1  - Caldero-Pascual, Maria
A1  - Geffroy, Ewan
A1  - Dillane, Mary
A1  - Grossart, Hans-Peter
A1  - Jennings, Eleanor
T1  - Impacts of extreme weather events on bacterial community composition of a temperate humic lake
JF  - Water
N2  - Extreme weather events are projected to increase in frequency and intensity as climate change continues. Heterotrophic bacteria play a critical role in lake ecosystems, yet little research has been done to determine how they are affected by such extremes. The purpose of this study was to use high-throughput sequencing to explore the bacterial community composition of a humic oligotrophic lake on the North Atlantic Irish coast and to assess the impacts on composition dynamics related to extreme weather events. Samples for sequencing were collected from Lough Feeagh on a fortnightly basis from April to November 2018. Filtration was used to separate free-living and particle-associated bacterial communities and amplicon sequencing was performed for the 16S rRNA V4 region. Two named storms, six high discharge events, and one drought period occurred during the sampling period. These events had variable, context-dependent effects on bacterial communities in Lough Feeagh. The particle-associated community was found to be more likely to respond to physical changes, such as mixing, while the free-living population responded to changes in nutrient and carbon concentrations. Generally, however, the high stability of the bacterial community observed in Lough Feeagh suggests that the bacterial community is relatively resilient to extreme weather events.
KW  - extreme weather event
KW  - storm
KW  - drought
KW  - bacteria
KW  - free-living
KW  - particle-associated
KW  - humic lake
Y1  - 2020
U6  - https://doi.org/10.3390/w12102757
SN  - 2073-4441
VL  - 12
IS  - 10
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Schellenberg, Johannes
A1  - Reichert, Jessica
A1  - Hardt, Martin
A1  - Klingelhöfer, Ines
A1  - Morlock, Gertrud
A1  - Schubert, Patrick
A1  - Bižić, Mina
A1  - Grossart, Hans-Peter
A1  - Kämpfer, Peter
A1  - Wilke, Thomas
A1  - Glaeser, Stefanie P.
T1  - The bacterial microbiome of the long-term aquarium cultured high-microbial abundance sponge Haliclona cnidata
BT  - sustained bioactivity despite community shifts under detrimental conditions
JF  - Frontiers in Marine Science
N2  - Marine sponges host highly diverse but specific bacterial communities that provide essential functions for the sponge holobiont, including antimicrobial defense. Here, we characterized the bacterial microbiome of the marine sponge Haliclona cnidata that has been in culture in an artificial marine aquarium system. We tested the hypotheses (1) that the long-term aquarium cultured sponge H. cnidata is tightly associated with a typical sponge bacterial microbiota and (2) that the symbiotic Bacteria sustain bioactivity under harmful environmental conditions to facilitate holobiont survival by preventing pathogen invasion. Microscopic and phylogenetic analyses of the bacterial microbiota revealed that H. cnidata represents a high microbial abundance (HMA) sponge with a temporally stable bacterial community that significantly shifts with changing aquarium conditions. A 4-week incubation experiment was performed in small closed aquarium systems with antibiotic and/or light exclusion treatments to reduce the total bacterial and photosynthetically active sponge-associated microbiota to a treatment-specific resilient community. While the holobiont was severely affected by the experimental treatment (i.e., bleaching of the sponge, reduced bacterial abundance, shifted bacterial community composition), the biological defense and bacterial community interactions (i.e., quorum sensing activity) remained intact. 16S rRNA gene amplicon sequencing revealed a resilient community of 105 bacterial taxa, which remained in the treated sponges. These 105 taxa accounted for a relative abundance of 72-83% of the bacterial sponge microbiota of non-treated sponge fragments that have been cultured under the same conditions. We conclude that a sponge-specific resilient community stays biologically active under harmful environmental conditions, facilitating the resilience of the holobiont. In H. cnidata, bacteria are located in bacteriocytes, which may have contributed to the observed phenomenon.
KW  - HMA sponge
KW  - bacterial symbionts
KW  - holobiont
KW  - antimicrobial defense
KW  - quorum sensing
KW  - bacteriocytes
Y1  - 2020
U6  - https://doi.org/10.3389/fmars.2020.00266
SN  - 2296-7745
VL  - 7
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Huang, Lixing
A1  - Qiao, Ying
A1  - Xu, Wei
A1  - Gong, Linfeng
A1  - He, Rongchao
A1  - Qi, Weilu
A1  - Gao, Qiancheng
A1  - Cai, Hongyan
A1  - Grossart, Hans-Peter
A1  - Yan, Qingpi
T1  - Full-length transcriptome
BT  - a reliable alternative for single-cell RNA-seq analysis in the spleen of teleost without reference genome
JF  - Frontiers in immunology
N2  - Fish is considered as a supreme model for clarifying the evolution and regulatory mechanism of vertebrate immunity. However, the knowledge of distinct immune cell populations in fish is still limited, and further development of techniques advancing the identification of fish immune cell populations and their functions are required. Single cell RNA-seq (scRNA-seq) has provided a new approach for effective in-depth identification and characterization of cell subpopulations. Current approaches for scRNA-seq data analysis usually rely on comparison with a reference genome and hence are not suited for samples without any reference genome, which is currently very common in fish research. Here, we present an alternative, i.e. scRNA-seq data analysis with a full-length transcriptome as a reference, and evaluate this approach on samples from Epinephelus coioides-a teleost without any published genome. We show that it reconstructs well most of the present transcripts in the scRNA-seq data achieving a sensitivity equivalent to approaches relying on genome alignments of related species. Based on cell heterogeneity and known markers, we characterized four cell types: T cells, B cells, monocytes/macrophages (Mo/M phi) and NCC (non-specific cytotoxic cells). Further analysis indicated the presence of two subsets of Mo/M phi including M1 and M2 type, as well as four subsets in B cells, i.e. mature B cells, immature B cells, pre B cells and early-pre B cells. Our research will provide new clues for understanding biological characteristics, development and function of immune cell populations of teleost. Furthermore, our approach provides a reliable alternative for scRNA-seq data analysis in teleost for which no reference genome is currently available.
KW  - scRNA-seq
KW  - full-length transcriptome
KW  - immune cell population
KW  - teleost
KW  - infection
Y1  - 2021
U6  - https://doi.org/10.3389/fimmu.2021.737332
SN  - 1664-3224
VL  - 12
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Aichner, Bernhard
A1  - Dubbert, David
A1  - Kiel, Christine
A1  - Kohnert, Katrin
A1  - Ogashawara, Igor
A1  - Jechow, Andreas
A1  - Harpenslager, Sarah-Faye
A1  - Hölker, Franz
A1  - Nejstgaard, Jens Christian
A1  - Grossart, Hans-Peter
A1  - Singer, Gabriel
A1  - Wollrab, Sabine
A1  - Berger, Stella Angela
T1  - Spatial and seasonal patterns of water isotopes in northeastern German lakes
JF  - Earth system science data : ESSD
N2  - Water stable isotopes (delta O-18 and delta H-2) were analyzed in samples collected in lakes, associated with riverine systems in northeastern Germany, throughout 2020. The dataset (Aichner et al., 2021; https://doi.org/10.1594/PANGAEA.935633) is derived from water samples collected at (a) lake shores (sampled in March and July 2020), (b) buoys which were temporarily installed in deep parts of the lake (sampled monthly from March to October 2020), (c) multiple spatially distributed spots in four selected lakes (in September 2020), and (d) the outflow of Muggelsee (sampled biweekly from March 2020 to January 2021). At shores, water was sampled with a pipette from 40-60 cm below the water surface and directly transferred into a measurement vial, while at buoys a Limnos water sampler was used to obtain samples from 1 m below the surface. Isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer, with a measurement uncertainty of < 0.15 parts per thousand (delta O-18) and < 0.0 parts per thousand (delta H-2). The data give information about the vegetation period and the full seasonal isotope amplitude in the sampled lakes and about spatial isotope variability in different branches of the associated riverine systems.
Y1  - 2022
U6  - https://doi.org/10.5194/essd-14-1857-2022
SN  - 1866-3508
SN  - 1866-3516
VL  - 14
IS  - 4
SP  - 1857
EP  - 1867
PB  - Copernicus
CY  - Göttingen
ER  - 
TY  - JOUR
A1  - Ilicic, Doris
A1  - Grossart, Hans-Peter
T1  - Basal parasitic fungi in marine food webs-a mystery yet to unravel
JF  - Journal of Fungi
N2  - Although aquatic and parasitic fungi have been well known for more than 100 years, they have only recently received increased awareness due to their key roles in microbial food webs and biogeochemical cycles. There is growing evidence indicating that fungi inhabit a wide range of marine habitats, from the deep sea all the way to surface waters, and recent advances in molecular tools, in particular metagenome approaches, reveal that their diversity is much greater and their ecological roles more important than previously considered. Parasitism constitutes one of the most widespread ecological interactions in nature, occurring in almost all environments. Despite that, the diversity of fungal parasites, their ecological functions, and, in particular their interactions with other microorganisms remain largely speculative, unexplored and are often missing from current theoretical concepts in marine ecology and biogeochemistry. In this review, we summarize and discuss recent research avenues on parasitic fungi and their ecological potential in marine ecosystems, e.g., the fungal shunt, and emphasize the need for further research.
KW  - basal fungi
KW  - parasites
KW  - Chytridiomycota
KW  - Rozellomycota
KW  - food web
KW  - biological carbon pump
Y1  - 2022
U6  - https://doi.org/10.3390/jof8020114
SN  - 2309-608X
VL  - 8
IS  - 2
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Riemann, Lasse
A1  - Rahav, Eyal
A1  - Passow, Uta
A1  - Grossart, Hans-Peter
A1  - de Beer, Dirk
A1  - Klawonn, Isabell
A1  - Eichner, Meri
A1  - Benavides, Mar
A1  - Bar-Zeev, Edo
T1  - Planktonic aggregates as hotspots for heterotrophic diazotrophy: the plot thickens
JF  - Frontiers in microbiology
N2  - Biological dinitrogen (N-2) fixation is performed solely by specialized bacteria and archaea termed diazotrophs, introducing new reactive nitrogen into aquatic environments. 
Conventionally, phototrophic cyanobacteria are considered the major diazotrophs in aquatic environments. However, accumulating evidence indicates that diverse non-cyanobacterial diazotrophs (NCDs) inhabit a wide range of aquatic ecosystems, including temperate and polar latitudes, coastal environments and the deep ocean. NCDs are thus suspected to impact global nitrogen cycling decisively, yet their ecological and quantitative importance remain unknown. Here we review recent molecular and biogeochemical evidence demonstrating that pelagic NCDs inhabit and thrive especially on aggregates in diverse aquatic ecosystems. Aggregates are characterized by reduced-oxygen microzones, high C:N ratio (above Redfield) and high availability of labile carbon as compared to the ambient water. 
We argue that planktonic aggregates are important loci for energetically-expensive N-2 fixation by NCDs and propose a conceptual framework for aggregate-associated N-2 fixation. Future studies on aggregate-associated diazotrophy, using novel methodological approaches, are encouraged to address the ecological relevance of NCDs for nitrogen cycling in aquatic environments.
KW  - aggregates
KW  - nitrogen fixation
KW  - heterotrophic bacteria
KW  - marine
KW  - aquatic
KW  - NCDs
Y1  - 2022
U6  - https://doi.org/10.3389/fmicb.2022.875050
SN  - 1664-302X
VL  - 13
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Zoccarato, Luca
A1  - Sher, Daniel
A1  - Miki, Takeshi
A1  - Segre, Daniel
A1  - Grossart, Hans-Peter
T1  - A comparative whole-genome approach identifies bacterial traits for marine microbial interactions
JF  - Communications biology
N2  - Luca Zoccarato, Daniel Sher et al. leverage publicly available bacterial genomes from marine and other environments to examine traits underlying microbial interactions.
Their results provide a valuable resource to investigate clusters of functional and linked traits to better understand marine bacteria community assembly and dynamics.  

Microbial interactions shape the structure and function of microbial communities with profound consequences for biogeochemical cycles and ecosystem health. Yet, most interaction mechanisms are studied only in model systems and their prevalence is unknown. To systematically explore the functional and interaction potential of sequenced marine bacteria, we developed a trait-based approach, and applied it to 473 complete genomes (248 genera), representing a substantial fraction of marine microbial communities. 

We identified genome functional clusters (GFCs) which group bacterial taxa with common ecology and life history. Most GFCs revealed unique combinations of interaction traits, including the production of siderophores (10% of genomes), phytohormones (3-8%) and different B vitamins (57-70%). Specific GFCs, comprising Alpha- and Gammaproteobacteria, displayed more interaction traits than expected by chance, and are thus predicted to preferentially interact synergistically and/or antagonistically with bacteria and phytoplankton. Linked trait clusters (LTCs) identify traits that may have evolved to act together (e.g., secretion systems, nitrogen metabolism regulation and B vitamin transporters), providing testable hypotheses for complex mechanisms of microbial interactions. 

Our approach translates multidimensional genomic information into an atlas of marine bacteria and their putative functions, relevant for understanding the fundamental rules that govern community assembly and dynamics.
Y1  - 2022
U6  - https://doi.org/10.1038/s42003-022-03184-4
SN  - 2399-3642
VL  - 5
IS  - 1
PB  - Springer Nature
CY  - Berlin
ER  - 
TY  - GEN
A1  - Wachs, Sebastian
A1  - Wright, Michelle F.
A1  - Sittichai, Ruthaychonnee
A1  - Singh, Ritu
A1  - Biswal, Ramakrishna
A1  - Kim, Eun-mee
A1  - Yang, Soeun
A1  - Gámez-Guadix, Manuel
A1  - Almendros, Carmen
A1  - Flora, Katerina
A1  - Daskalou, Vassiliki
A1  - Maziridou, Evdoxia
T1  - Correction: Associations between witnessing and perpetrating online hate in eight countries: The Buffering Effects of Problem-Focused Coping.
T2  - International Journal Environmental Research and Public Health
Y1  - 2021
U6  - https://doi.org/10.3390/ijerph18052609
SN  - 1660-4601
VL  - 18
IS  - 3992
SP  - 1
EP  - 2
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Sanchez Sanz, Arturo
A1  - Laudenbach, Benoît
A1  - Weiß, Adrian
A1  - Werner, Eva
A1  - Stachon, Markus
A1  - Anders, Friedrich
A1  - Barthel, Christian
A1  - Berrens, Dominik
A1  - Avalli, Andrea
A1  - Vandewalle, Alexander
A1  - Ferrara, Pasquale
A1  - Pohl, Patrik
ED  - Ambühl, Annemarie
ED  - Carlà-Uhink, Filippo
ED  - Rollinger, Christian
ED  - Walde, Christine
T1  - Spring Issue
T2  - thersites
Y1  - 2023
U6  - https://doi.org/10.34679/thersites.vol16
SN  - 2364-7612
VL  - 2023
IS  - 16
ER  - 
TY  - JOUR
A1  - Inceoglu, Fadil
A1  - Shprits, Yuri
A1  - Heinemann, Stephan G.
A1  - Bianco, Stefano
T1  - Identification of coronal holes on AIA/SDO images using unsupervised machine learning
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - Through its magnetic activity, the Sun governs the conditions in Earth's vicinity, creating space weather events, which have drastic effects on our space- and ground-based technology. 
One of the most important solar magnetic features creating the space weather is the solar wind that originates from the coronal holes (CHs). 
The identification of the CHs on the Sun as one of the source regions of the solar wind is therefore crucial to achieve predictive capabilities. 

In this study, we used an unsupervised machine-learning method, k-means, to pixel-wise cluster the passband images of the Sun taken by the Atmospheric Imaging Assembly on the Solar Dynamics Observatory in 171, 193, and 211 angstrom in different combinations. 

Our results show that the pixel-wise k-means clustering together with systematic pre- and postprocessing steps provides compatible results with those from complex methods, such as convolutional neural networks. 
More importantly, our study shows that there is a need for a CH database where a consensus about the CH boundaries is reached by observers independently. 
This database then can be used as the "ground truth," when using a supervised method or just to evaluate the goodness of the models.
Y1  - 2022
U6  - https://doi.org/10.3847/1538-4357/ac5f43
SN  - 1538-4357
VL  - 930
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  - 
TY  - JOUR
A1  - Smirnov, Artem G.
A1  - Kronberg, Elena A.
A1  - Daly, Patrick W.
A1  - Aseev, Nikita
A1  - Shprits, Yuri
A1  - Kellerman, Adam C.
T1  - Adiabatic Invariants Calculations for Cluster Mission: A Long-Term Product for Radiation Belts Studies
JF  - Journal of Geophysical Research: Space Physics
N2  - The Cluster mission has produced a large data set of electron flux measurements in the Earth's magnetosphere since its launch in late 2000. Electron fluxes are measured using Research with Adaptive Particle Imaging Detector (RAPID)/Imaging Electron Spectrometer (IES) detector as a function of energy, pitch angle, spacecraft position, and time. However, no adiabatic invariants have been calculated for Cluster so far. In this paper we present a step-by-step guide to calculations of adiabatic invariants and conversion of the electron flux to phase space density (PSD) in these coordinates. The electron flux is measured in two RAPID/IES energy channels providing pitch angle distribution at energies 39.2-50.5 and 68.1-94.5 keV in nominal mode since 2004. A fitting method allows to expand the conversion of the differential fluxes to the range from 40 to 150 keV. Best data coverage for phase space density in adiabatic invariant coordinates can be obtained for values of second adiabatic invariant, K, similar to 10(2), and values of the first adiabatic invariant mu in the range approximate to 5-20 MeV/G. Furthermore, we describe the production of a new data product "LSTAR," equivalent to the third adiabatic invariant, available through the Cluster Science Archive for years 2001-2018 with 1-min resolution. The produced data set adds to the availability of observations in Earth's radiation belts region and can be used for long-term statistical purposes.
KW  - L-Asterisk
KW  - magnetosphere
KW  - electrons
KW  - model
Y1  - 2019
VL  - 125
IS  - 2
PB  - John Wiley & Sons, Inc.
CY  - New Jersey
ER  - 
TY  - JOUR
A1  - Kuhlman, Sabine
T1  - Back to bureaucracy?
BT  - the advent of the neo-weberian state in Germany
JF  - Journal of policy studies
N2  - In this contribution, the emergence of the neo-Weberian state (NWS) is analyzed with regard to German public administration. Drawing on the concept of a governance space, which consists of a hierarchy, markets, and networks, we distinguish between four empirical manifestations of the NWS, namely, the NWS as (1) come back of the public/ re-municipalization; (2) re-hierarchization; (3) de-agencification; (4) de-escalation in performance management. These movements can, on the one hand, be interpreted as a (partial) reversal of New Public Management (NPM) approaches and a “swinging back of the pendulum” (see Kuhlmann & Wollmann, 2019) toward public and classical Weberian principles (e.g., hierarchy, regulation, institutional re-aggregation). This reversal re-strengthened the hierarchy within the overall governance space to the detriment of, but without completely replacing, market mechanisms and networks. NPM’s failure to deliver what it promised and its inappropriateness as a response to more recent challenges connected to crises and wicked problems have engendered a partial return of the public and a move away from the economization logic of NPM. On the other hand, post-NPM reversals and managerial de-escalation gave rise to hybrid models that merge NPM and classic Weberian administration. While some well-functioning combinations of NPM and Weberianism exist, the hybridization of “old” and “neo” elements has also provoked ambivalent and negative assessments regarding the actual functioning of the NWS in Germany. Our analysis suggests that the NWS is only partially suitable as a model for reform and future administrative modernization, largely depending on the context surrounding reform and implementation practices.
KW  - weo-weberian State
KW  - bureaucracy
KW  - post-new public management
KW  - hierarchy
KW  - re-municipalization
KW  - crisis
Y1  - 2024
U6  - https://doi.org/10.52372/jps39202
SN  - 2799-9130
SN  - 2800-0714
VL  - 39
IS  - 2
SP  - 11
EP  - 44
PB  - Graduate School of Public Administration
CY  - Seoul
ER  - 
TY  - JOUR
A1  - Asante, Drusilla Obenewaa
A1  - Osei, Francis
A1  - Abdul-Samed, Fridaus
A1  - Nanevie, Victoria Dzifa
T1  - Knowledge and participation in exercise and physical activity among pregnant women in Ho, Ghana
JF  - Frontiers in Public Health
N2  - Background
Physical activity (PA) and exercise have been identified to improve the general fitness and health. 
Although, the Pregnancy Physical Activity Questionnaire (PPAQ) has been validated for use in assessing PA in pregnant women. However, understanding the knowledge and participation levels of PA in pregnant women in the underdeveloped regions of Ghana is of clinical relevance to foster education and promotion of PA. In Ghana, pregnant women believe the "myth" (mostly in rural areas and underdeveloped regions) that exercising in the first trimester might lead to miscarriage. 
Thus, the main objective of this study was to investigate the extent of knowledge and participation levels in PA among pregnant women in Ho, Ghana using a self-developed questionnaire which consisted of some questions adapted from the PPAQ. MethodsSeventy-seven (n = 77) pregnant women between the ages of 18-50 years were recruited from three hospitals across the Ho municipality of Ghana. 
A self-developed questionnaire which consisted of some questions taken from the PPAQ was administered to participants under the researchers' supervision. Spearman's correlation analysis was used to find the association between the level of participation in PA, knowledge of PA and gestational age among pregnant women. 

Results
From the total participants (n = 77) recruited, 57 (74%) of the participants scored high in PA knowledge. 
Most of the participants 48 (62.3%) answered that PA promotes healthy pregnancy. Participants who reported barriers to PA during pregnancy were no exercise habits 51 (66.2%), having no time 17 (22.1%) and fear of miscarriage 9 (11.7%). 
There was a significant (p < 0.05) association between the level of participation and gestational age. No significant (p > 0.05) association between the level of participation and knowledge of PA was observed. 

Conclusion
There is a high level of knowledge of PA among pregnant women in Ho, Ghana. However, most pregnant women rather engage in PA as their gestational age increases. Thus, to foster sustainable exercise participation during pregnancy, all healthcare providers saddled with the responsibility of providing maternal healthcare must strengthen the education and promotion of exercise and PA among pregnant women in Ho, Ghana.
KW  - physical activity
KW  - barriers to physical activity
KW  - education
KW  - pregnancy
KW  - gestational age
Y1  - 2022
U6  - https://doi.org/10.3389/fpubh.2022.927191
SN  - 2296-2565
VL  - 10
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - von Steinkeller, Annika
A1  - Grosse, Gerlind
T1  - Children are more social when playing analog games together than digital games
JF  - Computers in Human Behavior Reports
N2  - Digital media are being used more and more frequently by children and for a wide variety of functions. 
However, there are no studies to date that examine the effect of such use on peer interactions and the occurrence of prosocial behavior in peers. 
For parents, it has been found that when using digital media only few parents respond responsively to their children's attempts at interaction and also very rarely, they communicate with them verbally and nonverbally.

In the present study, we investigated how playing a game in a digital versus analog form influences in-teractions (especially prosocial behavior) of peers.
We used an experimental situation, where 24 dyads of 4-10-year-old children were examined. Each of the dyads was randomly assigned to a condition where they played either a digital or analog game together. Various interaction parameters and prosocial behavior during and after the game were analyzed.

Results show that children in the analog condition communicated verbally with each other more often, responded more often to interaction attempts of their partners and showed less often negative forms of inter-action and more often positive forms of interaction than children in the digital condition. 
However, the type of medium had no influence on prosocial behavior after the game situation. 
These results suggest that the format of a game (digital vs. analog) has a decisive influence on peer interactions concerning their communication during but not their prosocial behavior after the game situation.
KW  - child development
KW  - peer interactions
KW  - media
KW  - prosocial behavior
KW  - digital
KW  - games
Y1  - 2022
U6  - https://doi.org/10.1016/j.chbr.2022.100195
SN  - 2451-9588
VL  - 6
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Winkelbeiner, Nicola Lisa
A1  - Wandt, Viktoria Klara Veronika
A1  - Ebert, Franziska
A1  - Lossow, Kristina
A1  - Bankoglu, Ezgi E.
A1  - Martin, Maximilian
A1  - Mangerich, Aswin
A1  - Stopper, Helga
A1  - Bornhorst, Julia
A1  - Kipp, Anna Patricia
A1  - Schwerdtle, Tanja
T1  - A Multi-Endpoint Approach to Base Excision Repair Incision Activity Augmented by PARylation and DNA Damage Levels in Mice
BT  - Impact of Sex and Age
JF  - International Journal of Molecular Sciences
N2  - Investigation of processes that contribute to the maintenance of genomic stability is one crucial factor in the attempt to understand mechanisms that facilitate ageing. The DNA damage response (DDR) and DNA repair mechanisms are crucial to safeguard the integrity of DNA and to prevent accumulation of persistent DNA damage. Among them, base excision repair (BER) plays a decisive role. BER is the major repair pathway for small oxidative base modifications and apurinic/apyrimidinic (AP) sites. We established a highly sensitive non-radioactive assay to measure BER incision activity in murine liver samples. Incision activity can be assessed towards the three DNA lesions 8-oxo-2’-deoxyguanosine (8-oxodG), 5-hydroxy-2’-deoxyuracil (5-OHdU), and an AP site analogue. We applied the established assay to murine livers of adult and old mice of both sexes. Furthermore, poly(ADP-ribosyl)ation (PARylation) was assessed, which is an important determinant in DDR and BER. Additionally, DNA damage levels were measured to examine the overall damage levels. No impact of ageing on the investigated endpoints in liver tissue were found. However, animal sex seems to be a significant impact factor, as evident by sex-dependent alterations in all endpoints investigated. Moreover, our results revealed interrelationships between the investigated endpoints indicative for the synergetic mode of action of the cellular DNA integrity maintaining machinery.
KW  - maintenance of genomic integrity
KW  - ageing
KW  - sex
KW  - DNA damage
KW  - base excision repair (incision activity)
KW  - DNA damage response
KW  - poly(ADP-ribosyl)ation
KW  - liver
Y1  - 2020
U6  - https://doi.org/10.3390/ijms21186600
SN  - 1422-0067
VL  - 21
IS  - 18
PB  - Molecular Diversity Preservation International
CY  - Basel
ER  - 
TY  - JOUR
A1  - Schmidt, Hendrikje
A1  - Felisatti, Arianna
A1  - Aster, Michael von
A1  - Wilbert, Jürgen
A1  - Moers, Arpad von
A1  - Fischer, Martin H.
T1  - Neuromuscular diseases affect number representation and processing
BT  - An exploratory study
JF  - Frontiers in psychology / Frontiers Research Foundation
N2  - Spinal muscular atrophy (SMA) and Duchenne muscular dystrophy (DMD) both are rare genetic neuromuscular diseases with progressive loss of motor ability. The neuromotor developmental course of those diseases is well documented. In contrast, there is only little evidence about characteristics of general and specific cognitive development. In both conditions the final motor outcome is characterized by an inability to move autonomously: children with SMA never accomplish independent motoric exploration of their environment, while children with DMD do but later lose this ability again. These profound differences in developmental pathways might affect cognitive development of SMA vs. DMD children, as cognition is shaped by individual motor experiences. DMD patients show impaired executive functions, working memory, and verbal IQ, whereas only motor ability seems to be impaired in SMA. Advanced cognitive capacity in SMA may serve as a compensatory mechanism for achieving in education, career progression, and social satisfaction. This study aimed to relate differences in basic numerical concepts and arithmetic achievement in SMA and DMD patients to differences in their motor development and resulting sensorimotor and environmental experiences. Horizontal and vertical spatial-numerical associations were explored in SMA/DMD children ranging between 6 and 12 years through the random number generation task. Furthermore, arithmetic skills as well as general cognitive ability were assessed. Groups differed in spatial number processing as well as in arithmetic and domain-general cognitive functions. Children with SMA showed no horizontal and even reversed vertical spatial-numerical associations. Children with DMD on the other hand revealed patterns in spatial numerical associations comparable to healthy developing children. From the embodied Cognition perspective, early sensorimotor experience does play a role in development of mental number representations. However, it remains open whether and how this becomes relevant for the acquisition of higher order cognitive and arithmetic skills.
KW  - spatial-numerical associations
KW  - numerical processing
KW  - mathematics
KW  - child development
KW  - embodied cognition
KW  - neuromuscular disease
KW  - spinal muscular atrophy
KW  - Duchenne muscular dystrophy
Y1  - 2021
U6  - https://doi.org/10.3389/fpsyg.2021.697881
SN  - 1664-1078
VL  - 12
PB  - Frontiers Research Foundation
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Richly, Keven
A1  - Brauer, Janos
A1  - Schlosser, Rainer
T1  - Predicting location probabilities of drivers to improved dispatch decisions of transportation network companies based on trajectory data
JF  - Proceedings of the 9th International Conference on Operations Research and Enterprise Systems - ICORES
N2  - The demand for peer-to-peer ridesharing services increased over the last years rapidly. To cost-efficiently dispatch orders and communicate accurate pick-up times is challenging as the current location of each available driver is not exactly known since observed locations can be outdated for several seconds. The developed trajectory visualization tool enables transportation network companies to analyze dispatch processes and determine the causes of unexpected delays. As dispatching algorithms are based on the accuracy of arrival time predictions, we account for factors like noise, sample rate, technical and economic limitations as well as the duration of the entire process as they have an impact on the accuracy of spatio-temporal data. To improve dispatching strategies, we propose a prediction approach that provides a probability distribution for a driver’s future locations based on patterns observed in past trajectories. We demonstrate the capabilities of our prediction results to ( i) avoid critical delays, (ii) to estimate waiting times with higher confidence, and (iii) to enable risk considerations in dispatching strategies.
KW  - trajectory data
KW  - location prediction algorithm
KW  - Peer-to-Peer ridesharing
KW  - transport network companies
KW  - risk-aware dispatching
Y1  - 2020
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Wagner, Birgit
A1  - Rosenberg, Nicole
A1  - Hofmann, Laura
A1  - Maaß, Ulrike
T1  - Web-based bereavement care
BT  - a systematic review and meta-analysis
JF  - Frontiers in psychiatry
N2  - Background:
Web-based interventions have been introduced as novel and effective treatments for mental disorders and, in recent years, specifically for the bereaved. However, a systematic summary of the effectiveness of online interventions for people experiencing bereavement is still missing.

Objective:
A systematic literature search was conducted by four reviewers who reviewed and meta-analytically summarized the evidence for web-based interventions for bereaved people.

Methods:
Systematic searches (PubMed, Web of Science, PsycInfo, PsycArticles, Medline, and CINAHL) resulted in seven randomized controlled trials (N= 1,257) that addressed adults having experienced bereavement using internet-based interventions. We used random effects models to summarize treatment effects for between-group comparisons (treatmentvs.control at post) and stability over time (postvs.follow-up).

Results:
All web-based interventions were based on cognitive behavioral therapy (CBT). In comparison with control groups, the interventions showed moderate (g= .54) to large effects (g= .86) for symptoms of grief and posttraumatic stress disorder (PTSD), respectively. The effect for depression was small (g= .44). All effects were stable over time. A higher number of treatment sessions achieved higher effects for grief symptoms and more individual feedback increased effects for depression. Other moderators (i.e.dropout rate, time since loss, exposure) did not significantly reduce moderate degrees of heterogeneity between the studies. 

Limitations:
The number of includable studies was low in this review resulting to lower power for moderator analyses in particular.

Conclusions:
Overall, the results of web-based bereavement interventions are promising, and its low-threshold approach might reduce barriers to bereavement care. Nonetheless, future research should further examine potential moderators and specific treatment components (e.g.exposure, feedback) and compare interventions with active controls.
KW  - grief
KW  - bereavement
KW  - depression
KW  - post-traumatic stress disorder
KW  - internet
KW  - e-health
KW  - intervention
KW  - psychotherapy
Y1  - 2020
U6  - https://doi.org/10.3389/fpsyt.2020.00525
SN  - 1664-0640
VL  - 11
PB  - Frontiers Media
CY  - Lausanne
ER  - 
TY  - JOUR
A1  - Wagner, Birgit
A1  - Hofmann, Laura
A1  - Maaß, Ulrike
T1  - Online-group intervention after suicide bereavement through the use of webinars
BT  - study protocol for a randomized controlled trial
JF  - Trials
N2  - Introduction:
The death of a significant person through suicide is a very difficult experience and can have long-term impact on an individual's psychosocial and physical functioning. However, there are only few studies that have examined the effects of interventions in suicide survivors. In the present study, we examine an online-group intervention for people bereaved by suicide using a group-webinar. 

Methods:
The intervention was developed based on focus groups with the target group. The cognitive-behavioral 12-module webinar-based group intervention focuses on suicide bereavement-related themes such as feelings of guilt, stigmatization, meaning reconstruction and the relationship to the deceased. Further, the webinar includes testimonial videos and psychoeducation. The suicide survivors are randomized to the intervention or the waiting list in a group-cluster randomized controlled trial. Primary outcomes are suicidality (Beck Scale for Suicide Ideation) and depression (Beck Depression Inventory-II) and secondary outcomes are symptoms of prolonged grief disorder (Inventory of Complicated Grief-German Version ), posttraumatic stress disorder ( Revised Impact of Event Scale ), stigmatization (Stigma of Suicide and Suicide Survivor ) and posttraumatic cognitions (Posttraumatic Cognitions Inventory). 

Discussion:
Previous studies of Internet-based interventions for the bereaved were based on writing interventions showing large treatment effects. Little is known about the use of webinars as group interventions. Advantages and challenges of this novel approach of psychological interventions will be discussed.
KW  - Suicide bereavement
KW  - grief
KW  - group intervention
KW  - webinar
KW  - suicidality
KW  - prolonged grief disorder
KW  - randomized controlled trial
Y1  - 2020
U6  - https://doi.org/10.1186/s13063-019-3891-5
SN  - 1468-6694
SN  - 1745-6215
VL  - 21
IS  - 1
PB  - BioMed Central
CY  - London
ER  - 
TY  - JOUR
A1  - Maaß, Ulrike
A1  - Kühne, Franziska
A1  - Heinze, Peter Eric
A1  - Ay-Bryson, Destina Sevde
A1  - Weck, Florian
T1  - The concise measurement of clinical communication skills
BT  - Validation of a short scale
JF  - Frontiers in Psychiatry
N2  - Objective: There is a lack of brief rating scales for the reliable assessment of psychotherapeutic skills, which do not require intensive rater training and/or a high level of expertise. Thus, the objective is to validate a 14-item version of the Clinical Communication Skills Scale (CCSS-S).

Methods: Using a sample of N = 690 video-based ratings of role-plays with simulated patients, we calculated a confirmatory factor analysis and an exploratory structural equation modeling (ESEM), assessed convergent validities, determined inter-rater reliabilities and compared these with those who were either psychology students, advanced psychotherapy trainees, or experts.

Results: Correlations with other competence rating scales were high (rs > 0.86–0.89). The intraclass correlations ranged between moderate and good [ICC(2,2) = 0.65–0.80], with student raters yielding the lowest scores. The one-factor model only marginally replicated the data, but the internal consistencies were excellent (α = 0.91–95). The ESEM yielded a two-factor solution (Collaboration and Structuring and Exploration Skills).

Conclusion: The CCSS-S is a brief and valid rating scale that reliably assesses basic communication skills, which is particularly useful for psychotherapy training using standardized role-plays. To ensure good inter-rater reliabilities, it is still advisable to employ raters with at least some clinical experience. Future studies should further investigate the one- or two-factor structure of the instrument.
KW  - standardized patient
KW  - treatment integrity
KW  - measurement
KW  - therapist competence
KW  - role-play
KW  - psychotherapy process
Y1  - 2022
U6  - https://doi.org/10.3389/fpsyt.2022.977324
SN  - 1664-0640
VL  - 13
PB  - Frontiers
CY  - Lausanne, Schweiz
ER  - 
TY  - JOUR
A1  - Felisatti, Arianna
A1  - Aagten-Murphy, David
A1  - Laubrock, Jochen
A1  - Shaki, Samuel
A1  - Fischer, Martin H.
T1  - The brain’s asymmetric frequency tuning
BT  - asymmetric behavior originates from asymmetric perception
JF  - Symmetry / Molecular Diversity Preservation International (MDPI)
N2  - To construct a coherent multi-modal percept, vertebrate brains extract low-level features (such as spatial and temporal frequencies) from incoming sensory signals. However, because frequency processing is lateralized with the right hemisphere favouring low frequencies while the left favours higher frequencies, this introduces asymmetries between the hemispheres. Here, we describe how this lateralization shapes the development of several cognitive domains, ranging from visuo-spatial and numerical cognition to language, social cognition, and even aesthetic appreciation, and leads to the emergence of asymmetries in behaviour. We discuss the neuropsychological and educational implications of these emergent asymmetries and suggest future research approaches.
KW  - asymmetry
KW  - global
KW  - local
KW  - spatial frequencies
KW  - temporal frequencies
KW  - embodied cognition
Y1  - 2020
U6  - https://doi.org/10.3390/sym12122083
SN  - 2073-8994
VL  - 12
IS  - 12
PB  - MDPI
CY  - Basel
ER  -