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In this study, we analyze the forecast accuracy and profitability of buy recommendations published in five major German financial magazines for private households based on fundamental analysis. The results show a high average forecast accuracy but with a very high standard deviation, which indicates poor forecast accuracy with regard to individual stocks. The recommendation profitability slightly exceeds the performance of the MSCI World index. Considering the involved risk, which is represented by a high standard deviation, the excess returns appear to be insufficient.
The growing global demand for meat is being thwarted by shrinking agricultural areas, and opposes efforts to mitigate methane emissions and to improve public health. Cultured meat could contribute to solve these problems, but will such meat be marketable, competitive, and accepted? Using the Delphi method, this study explored the potential development of cultured meat by 2027. Despite the acknowledged urgency to develop sustainable meat alternatives, participants doubt that challenges regarding mass production, production costs, and consumer acceptance will be overcome by 2027. Considering the noticeable impacts of global warming, further research and development as well as a change in consumer perceptions is inevitable.
This paper challenges the solely rational view of the scenario technique as a strategy and foresight tool designed to cope with uncertainty by considering multiple possible future states. The paper employs an affordance-based view that allows for the identification and structuring of hidden, emergent attributes of the scenario technique beyond the intended ones. The suggested framework distinguishes between affordances (1) that are intended by the organization and relate to its goals, (2) that emergently generate organizational benefits, and (3) that do not relate to organizational but individual interests. Also, constraints in the use of scenarios are discussed. Affordance theory’s specific lens shows that the emergence of such attributes depends on the users’ specific intentions.
This study examines the course and driving forces of recent vegetation change in the Mongolian steppe. A sediment core covering the last 55years from a small closed-basin lake in central Mongolia was analyzed for its multi-proxy record at annual resolution. Pollen analysis shows that highest abundances of planted Poaceae and highest vegetation diversity occurred during 1977-1992, reflecting agricultural development in the lake area. A decrease in diversity and an increase in Artemisia abundance after 1992 indicate enhanced vegetation degradation in recent times, most probably because of overgrazing and farmland abandonment. Human impact is the main factor for the vegetation degradation within the past decades as revealed by a series of redundancy analyses, while climate change and soil erosion play subordinate roles. High Pediastrum (a green algae) influx, high atomic total organic carbon/total nitrogen (TOC/TN) ratios, abundant coarse detrital grains, and the decrease of C-13(org) and N-15 since about 1977 but particularly after 1992 indicate that abundant terrestrial organic matter and nutrients were transported into the lake and caused lake eutrophication, presumably because of intensified land use. Thus, we infer that the transition to a market economy in Mongolia since the early 1990s not only caused dramatic vegetation degradation but also affected the lake ecosystem through anthropogenic changes in the catchment area.
We investigate whether political ideology has an observable effect on decarbonization ambition, renewable power aims, and preferences for power system balancing technologies in four European countries. Based on the Energy Logics framework, we identify ideologically different transition strategies (state-centered, market-centered, grassroots-centered) contained in government policies and opposition party programs valid in 2019. We compare these policies and programs with citizen poll data. We find that ideology has a small effect: governments and political parties across the spectrum have similar, and relatively ambitious, decarbonization and renewables targets. This mirrors citizens' strong support for ambitious action regardless of their ideological self-description. However, whereas political positions on phasing out fossil fuel power are clear across the policy space, positions on phasing in new flexibility options to balance intermittent renewables are vague or non-existent. As parties and citizens agree on strong climate and renewable power aims, the policy ambition is likely to remain high, even if governments change.
Background: The linear noise approximation (LNA) is commonly used to predict how noise is regulated and exploited at the cellular level. These predictions are exact for reaction networks composed exclusively of first order reactions or for networks involving bimolecular reactions and large numbers of molecules. It is however well known that gene regulation involves bimolecular interactions with molecule numbers as small as a single copy of a particular gene. It is therefore questionable how reliable are the LNA predictions for these systems.
Results: We implement in the software package intrinsic Noise Analyzer (iNA), a system size expansion based method which calculates the mean concentrations and the variances of the fluctuations to an order of accuracy higher than the LNA. We then use iNA to explore the parametric dependence of the Fano factors and of the coefficients of variation of the mRNA and protein fluctuations in models of genetic networks involving nonlinear protein degradation, post-transcriptional, post-translational and negative feedback regulation. We find that the LNA can significantly underestimate the amplitude and period of noise-induced oscillations in genetic oscillators. We also identify cases where the LNA predicts that noise levels can be optimized by tuning a bimolecular rate constant whereas our method shows that no such regulation is possible. All our results are confirmed by stochastic simulations.
Conclusion: The software iNA allows the investigation of parameter regimes where the LNA fares well and where it does not. We have shown that the parametric dependence of the coefficients of variation and Fano factors for common gene regulatory networks is better described by including terms of higher order than LNA in the system size expansion. This analysis is considerably faster than stochastic simulations due to the extensive ensemble averaging needed to obtain statistically meaningful results. Hence iNA is well suited for performing computationally efficient and quantitative studies of intrinsic noise in gene regulatory networks.
In Vorbereitung zur Teilnahme am Times Higher Education Ranking hat die Universität Potsdam das Publikationsaufkommen im Rahmen einer Output-Analyse gemessen. Es stellte sich heraus, dass die Angabe der Affiliation, welche die Wissenschaftlerinnen und Wissenschaftler tätigen, eine wichtige Stellschraube zur Ermittlung der Grundzahl ist. Der vorliegende Artikel spiegelt die herausfordernde Ausgangssituation wider.
Verfügbare Allianz- und Nationallizenzen können eine Open-Access-Komponente beinhalten. Diese räumen den autorisierten Autoren oder Einrichtungen bestimmte Open-Access-Rechte zur Zweitveröffentlichung ein. Vorhandene Lizenzrechte zur Realisierung des Grünen Weges können somit zukünftig verstärkt genutzt werden. Dabei kann die Bibliothek eine aktive Rolle einnehmen. Präsentiert wird ein Workflow, der sich an der Checkliste für Repository-Manager orientiert. Sieben herausgearbeitete Schritte werden genannt und näher erläutert. An Beispielen wurde der Workflow getestet. Die Ergebnisse werden ebenfalls vorgestellt. Die Erweiterung des Workflows zur Identifizierung von Publikationen für die Zweitveröffentlichung lässt sich ggf. auch auf Creative-Commons-Lizenzen anwenden bzw. auf Zeitschriften, die keine Open-Access-Komponente haben.
Die Universität Potsdam hat 2018 zum zweiten Mal erfolgreich am Times Higher Education-Ranking (THE-Ranking) teilgenommen. Hierfür wurde erneut das Publikationsaufkommen inklusive der Verbreitung der IDs von Autorinnen und Autoren, wie bspw. ORCiD, Researcher-ID oder Google Scholar-ID, ermittelt. Die aus den Erkenntnissen der ersten bibliometrischen Output-Analyse abgeleiteten Maßnahmen wurden nun hinsichtlich ihrer Wirksamkeit beurteilt. Der vorliegende Artikel vergleicht die Ergebnisse beider Analysen und thematisiert die Entwicklungen und Implikationen seit dem Ergreifen der ersten Maßnahmen.
Die Universität Potsdam verwaltet seit 2015 einen DFG-geförderten Publikationsfonds. In den Publikationsjahren 2015 und 2017 wurden Outputanalysen durchgeführt. Open Access ist seit 2018 ein zentraler Bestandteil des Mittelverteilungsmodells. Der Artikel thematisiert die zentralen Erkenntnisse der letzten fünf Jahre und illustriert die entstandene Infrastruktur. Außerdem werden aktuelle Herausforderungen und mögliche Lösungsansätze der Transformation auf dem Weg hin zu 100 Prozent Open Access thematisiert.
Es darf gekocht werden
(2019)
Eine achtköpfige Delegation der Universität Potsdam (UP) besuchte vom 18. bis 21. November 2018 die Tel Aviv University (TAU) in Israel. Die Kooperation zwischen beiden Einrichtungen wurde durch einen »staff exchange« intensiviert. So konnten Mitarbeiter*innen der UP ihren Gegenpart an der TAU kennenlernen und sich inhaltlich austauschen. Der vorliegende Bericht basiert auf Gesprächen mit drei der insgesamt fünf Bibliotheksdirektorinnen sowie zwei weiteren Kolleginnen aus dem Bereich Erwerbung und Katalogisierung. Dabei wurden unterschiedliche Themenbereiche aus dem Bibliothekswesen und die Sicht beziehungsweise der Stand dazu an der TAU und der UP angesprochen. Der vorliegende Bericht geht auf die Themenfelder Bibliothekssystem, Open Access und Bibliothek als Raum ein.
Die Veränderungen im Bereich der Literaturerwerbung und -nutzung innerhalb der letzten sieben Jahre haben einen Neuentwurf des Mittelverteilungsmodells der Universitätsbibliothek Potsdam unumgänglich gemacht. Dieser gliedert sich klar in Segmente und verankert erstmals auch Open Access im Bibliotheksetat. Damit wird dem angestrebten Transformationsprozess Rechnung getragen.
Water deficit (drought stress) massively restricts plant growth and the yield of crops; reducing the deleterious effects of drought is therefore of high agricultural relevance. Drought triggers diverse cellular processes including the inhibition of photosynthesis, the accumulation of cell‐damaging reactive oxygen species and gene expression reprogramming, besides others. Transcription factors (TF) are central regulators of transcriptional reprogramming and expression of many TF genes is affected by drought, including members of the NAC family. Here, we identify the NAC factor JUNGBRUNNEN1 (JUB1) as a regulator of drought tolerance in tomato (Solanum lycopersicum). Expression of tomato JUB1 (SlJUB1) is enhanced by various abiotic stresses, including drought. Inhibiting SlJUB1 by virus‐induced gene silencing drastically lowers drought tolerance concomitant with an increase in ion leakage, an elevation of hydrogen peroxide (H2O2) levels and a decrease in the expression of various drought‐responsive genes. In contrast, overexpression of AtJUB1 from Arabidopsis thaliana increases drought tolerance in tomato, alongside with a higher relative leaf water content during drought and reduced H2O2 levels. AtJUB1 was previously shown to stimulate expression of DREB2A, a TF involved in drought responses, and of the DELLA genes GAI and RGL1. We show here that SlJUB1 similarly controls the expression of the tomato orthologs SlDREB1, SlDREB2 and SlDELLA. Furthermore, AtJUB1 directly binds to the promoters of SlDREB1, SlDREB2 and SlDELLA in tomato. Our study highlights JUB1 as a transcriptional regulator of drought tolerance and suggests considerable conservation of the abiotic stress‐related gene regulatory networks controlled by this NAC factor between Arabidopsis and tomato.
Strength training is an important means for performance development in young rowers. The purpose of this study was to examine the effects of a 9-week equal volume heavy-resistance strength training (HRST) versus strength endurance training (SET) in addition to regular rowing training on primary (e.g., maximal strength/power) and secondary outcomes (e.g., balance) in young rowers. Twenty-six female elite adolescent rowers were assigned to an HRST (n = 12; age: 13.2 ± 0.5 yrs; maturity-offset: +2.0 ± 0.5 yrs) or a SET group (n = 14; age: 13.1 ± 0.5 yrs; maturity-offset: +2.1 ± 0.5 yrs). HRST and SET comprised lower- (i.e., leg press/knee flexion/extension), upper-limbs (i.e., bench press/pull; lat-pull down), and complex exercises (i.e., rowing ergometer). HRST performed four sets with 12 repetitions per set at an intensity of 75–95% of the one-repetition maximum (1-RM). SET conducted four sets with 30 repetitions per set at 50–60% of the 1-RM. Training volume was matched for overall repetitions × intensity × training per week. Pre-post training, tests were performed for the assessment of primary [i.e., maximal strength (e.g., bench pull/knee flexion/extension 1-RM/isometric handgrip test), muscle power (e.g., medicine-ball push test, triple hop, drop jump, and countermovement jump), anaerobic endurance (400-m run), sport-specific performance (700-m rowing ergometer trial)] and secondary outcomes [dynamic balance (Y-balance test), change-of-direction (CoD) speed (multistage shuttle-run test)]. Adherence rate was >87% and one athlete of each group dropped out. Overall, 24 athletes completed the study and no test or training-related injuries occurred. Significant group × time interactions were observed for maximal strength, muscle power, anaerobic endurance, CoD speed, and sport-specific performance (p ≤ 0.05; 0.45 ≤ d ≤ 1.11). Post hoc analyses indicated larger gains in maximal strength and muscle power following HRST (p ≤ 0.05; 1.81 ≤ d ≤ 3.58) compared with SET (p ≤ 0.05; 1.04 ≤ d ≤ 2.30). Furthermore, SET (p ≤ 0.01; d = 2.08) resulted in larger gains in sport-specific performance compared with HRST (p < 0.05; d = 1.3). Only HRST produced significant pre-post improvements for anaerobic endurance and CoD speed (p ≤ 0.05; 1.84 ≤ d ≤ 4.76). In conclusion, HRST in addition to regular rowing training was more effective than SET to improve selected measures of physical fitness (i.e., maximal strength, muscle power, anaerobic endurance, and CoD speed) and SET was more effective than HRST to enhance sport-specific performance gains in female elite young rowers.
A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks
(2013)
A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.
Widespread flooding in June 2013 caused damage costs of €6 to 8 billion in Germany, and awoke many memories of the floods in August 2002, which resulted in total damage of €11.6 billion and hence was the most expensive natural hazard event in Germany up to now. The event of 2002 does, however, also mark a reorientation toward an integrated flood risk management system in Germany. Therefore, the flood of 2013 offered the opportunity to review how the measures that politics, administration, and civil society have implemented since 2002 helped to cope with the flood and what still needs to be done to achieve effective and more integrated flood risk management. The review highlights considerable improvements on many levels, in particular (1) an increased consideration of flood hazards in spatial planning and urban development, (2) comprehensive property-level mitigation and preparedness measures, (3) more effective flood warnings and improved coordination of disaster response, and (4) a more targeted maintenance of flood defense systems. In 2013, this led to more effective flood management and to a reduction of damage. Nevertheless, important aspects remain unclear and need to be clarified. This particularly holds for balanced and coordinated strategies for reducing and overcoming the impacts of flooding in large catchments, cross-border and interdisciplinary cooperation, the role of the general public in the different phases of flood risk management, as well as a transparent risk transfer system. Recurring flood events reveal that flood risk management is a continuous task. Hence, risk drivers, such as climate change, land-use changes, economic developments, or demographic change and the resultant risks must be investigated at regular intervals, and risk reduction strategies and processes must be reassessed as well as adapted and implemented in a dialogue with all stakeholders.
Flood damage has increased significantly and is expected to rise further in many parts of the world. For assessing potential changes in flood risk, this paper presents an integrated model chain quantifying flood hazards and losses while considering climate and land use changes. In the case study region, risk estimates for the present and the near future illustrate that changes in flood risk by 2030 are relatively low compared to historic periods. While the impact of climate change on the flood hazard and risk by 2030 is slight or negligible, strong urbanisation associated with economic growth contributes to a remarkable increase in flood risk. Therefore, it is recommended to frequently consider land use scenarios and economic developments when assessing future flood risks. Further, an adapted and sustainable risk management is necessary to encounter rising flood losses, in which non-structural measures are becoming more and more important. The case study demonstrates that adaptation by non-structural measures such as stricter land use regulations or enhancement of private precaution is capable of reducing flood risk by around 30 %. Ignoring flood risks, in contrast, always leads to further increasing losses-with our assumptions by 17 %. These findings underline that private precaution and land use regulation could be taken into account as low cost adaptation strategies to global climate change in many flood prone areas. Since such measures reduce flood risk regardless of climate or land use changes, they can also be recommended as no-regret measures.
Wie klingt Motivation?
(2018)
Hintergrund/Fragestellung: Während einer erfolgreichen Psychotherapie – so Miller und Rollnick (2013) – initiiert der Therapeut ein lautes Nachdenken über Veränderung (change talk), das eine Verhaltensänderung einleitet und verschiedene Facetten der Motivation eines Patienten spiegelt. Auf den preparatory change talk (desire, ability, reasons, need) folgt der mobilizing change talk (commitment, activation, taking steps) und schließlich die Verhaltensänderung. Die vorliegende Studie ist ein erster Versuch, deutsche Begriffe und Redewendungen zu analysieren, um Therapeuten die Einschätzung der Motivation eines Patienten zu erleichtern. Methodik: Das schrittweise Vorgehen entsprach weitgehend einem in der englischsprachigen Literatur beschriebenen Verfahren zur Einschätzung von Begriffen und Redewendungen hinsichtlich der Motivation eines Sprechers (vgl. Amrhein, 2009): (1) Generierung einer Sammlung relevanter Begriffe und Redewendungen, (2) Einschätzung der Stärke einer Formulierung durch 430 Probanden, (3) Bestimmung der Retestreliabilität anhand der Einschätzungen von 63 Probanden, (4) Kategorisierung von 140 Begriffen und Redewendungen durch drei Experten. Ergebnisse: Die ausgewählten Begriffe und Phrasen lassen sich zuverlässig den von Miller und Rollnick (2013) beschriebenen Kategorien Preparatory Change Talk oder Mobilizing Change Talk zuordnen, κ = .83 (95 % CI, .80 ≤ κ≤ .85), p < .001, und spiegeln darüber hinaus verschiedene Ausprägungen der Motivation eines Sprechers wider. Die Einschätzungen der Stärke einer Formulierung sind jedoch nicht stabil (Retestreliabilität: .21 ≤ rtt ≤.70). Schlussfolgerungen: Die Beachtung typischer Schlüsselwörter kann das richtige Timing einer Intervention erleichtern und darüber hinaus Auskunft über die „Entschlossenheit“ eines Patienten geben. Im Rahmen von Forschungsprojekten könnten auf der Basis erweiterter Sammlungen relevanter Begriffe und Redewendungen Algorithmen entwickelt werden, die eine Einschätzung der Motivation und damit prognostisch bedeutsame Aussagen erlauben.
Leveraging large-deviation statistics to decipher the stochastic properties of measured trajectories
(2021)
Extensive time-series encoding the position of particles such as viruses, vesicles, or individualproteins are routinely garnered insingle-particle tracking experiments or supercomputing studies.They contain vital clues on how viruses spread or drugs may be delivered in biological cells.Similar time-series are being recorded of stock values in financial markets and of climate data.Such time-series are most typically evaluated in terms of time-averaged mean-squareddisplacements (TAMSDs), which remain random variables for finite measurement times. Theirstatistical properties are different for differentphysical stochastic processes, thus allowing us toextract valuable information on the stochastic process itself. To exploit the full potential of thestatistical information encoded in measured time-series we here propose an easy-to-implementand computationally inexpensive new methodology, based on deviations of the TAMSD from itsensemble average counterpart. Specifically, we use the upper bound of these deviations forBrownian motion (BM) to check the applicability of this approach to simulated and real data sets.By comparing the probability of deviations fordifferent data sets, we demonstrate how thetheoretical bound for BM reveals additional information about observed stochastic processes. Weapply the large-deviation method to data sets of tracer beads tracked in aqueous solution, tracerbeads measured in mucin hydrogels, and of geographic surface temperature anomalies. Ouranalysis shows how the large-deviation properties can be efficiently used as a simple yet effectiveroutine test to reject the BM hypothesis and unveil relevant information on statistical propertiessuch as ergodicity breaking and short-time correlations.