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Fluorophore multimerization on a PEG backbone as a concept for signal amplification and lifetime modulation
No full textFluorescent labels have strongly contributed to many advancements in bioanalysis, molecular biology, molecular imaging, and medical diagnostics. Despite a large toolbox of molecular and nanoscale fluorophores to choose from, there is still a need for brighter labels, e.g., for flow cytometry and fluorescence microscopy, that are preferably of molecular nature. This requires versatile concepts for fluorophore multimerization, which involves the shielding of dyes from other chromophores and possible quenchers in their neighborhood. In addition, to increase the number of readout parameters for fluorescence microscopy and eventually also flow cytometry, control and tuning of the labels’ fluorescence lifetimes is desired. Searching for bright multi-chromophoric or multimeric labels, we developed PEGylated dyes bearing functional groups for their bioconjugation and explored their spectroscopic properties and photostability in comparison to those of the respective monomeric dyes for two exemplarily chosen fluorophores excitable at 488 nm. Subsequently, these dyes were conjugated with anti-CD4 and anti-CD8 immunoglobulins to obtain fluorescent conjugates suitable for the labeling of cells and beads. Finally, the suitability of these novel labels for fluorescence lifetime imaging and target discrimination based upon lifetime measurements was assessed. Based upon the results of our spectroscopic studies including measurements of fluorescence quantum yields (QY) and fluorescence decay kinetics we could demonstrate the absence of significant dye-dye interactions and self-quenching in these multimeric labels. Moreover, in a first fluorescence lifetime imaging (FLIM) study, we could show the future potential of this multimerization concept for lifetime discrimination and multiplexing.Open Access funding enabled and organized by Projekt DEAL.Bundesanstalt für Materialforschung und -prüfung (BAM) (4232)Peer Reviewe
Hitting the Sweet Spot? The Electoral Consequences of Supporting Minority Governments
No full textDoes supporting a minority cabinet harm a party’s electoral prospects? While minority governments have become more common in recent years, the electoral implications for parties supporting such cabinets remain unclear. Previous research suggests that support parties enjoy a favorable position, exerting policy influence while avoiding electoral losses associated with joining the government. However, we argue that this is only true for support parties without written agreements, as their support is less visible to voters. To test our argument, we compiled a novel dataset on the electoral performance of 563 parties in 304 elections across 31 countries since 1980. We estimate the effect of being a support party on subsequent electoral performance. Our findings indicate that parties which declare support perform better electorally than junior partners, while contract support parties do not. These insights shed light on the relationship between minority governments and electoral competition amidst growing party system fragmentation.German Research Foundationhttps://doi.org/10.13039/501100001659Peer Reviewe
Ab Initio Simulation of Raman Fingerprints of Sulfur/Carbon Copolymer Cathodes During Discharge of Li−S Batteries
No full textSulfur/carbon copolymers have emerged as promising alternatives for conventional crystalline sulfur cathodes for lithium‐sulfur batteries. Among these, sulfur‐ n ‐1,3‐diisopropenylbenzene (S/DIB) copolymers, which present a 3D network of DIB molecules interconnected via sulfur chains, have particularly shown a good performance and, therefore, have been under intensive experimental and theoretical investigations. However, their structural complexity and flexibility have hindered a clear understanding of their structural evolution during redox reactions at an atomistic level. Here, by performing state‐of‐the‐art ab initio molecular dynamics‐based Raman spectroscopy simulations, we investigate the spectral fingerprints of S/DIB copolymers arising from local structures during consecutive reactions with lithium. We discuss in detail Raman spectral changes in particular frequency ranges which are common in S/DIB copolymers having short sulfur chains and those consisting of longer ones. We also highlight those distinctive spectroscopic fingerprints specific to local S/DIB structures containing only short or long sulfur chains. This distinction could serve to help distinguish between them experimentally during discharge. Our theoretically predicted results are in a good agreement with experimental Raman measurements on coin cells at different discharge stages. This work represents, for the first time, an attempt to compute Raman fingerprints of sulfur/carbon copolymer cathodes during battery operation including quantum‐chemical and finite‐temperature effects, and provides a guideline for Raman spectral changes of arbitrary electrodes during discharge.420536636Bull Cluster at the Center for Information Services and High Performance Computing (ZIH) at TU DresdenPeer Reviewe
Participatory and Spatially Explicit Assessment to Envision the Future of Land-Use/Land-Cover Change Scenarios on Selected Ecosystem Services in Southwestern Ghana
No full textSettlement expansion and commercial agriculture affect landscape sustainability and ecosystem service provision. Integrated landscape approaches are promoted to negotiate trade-offs between competing land uses and their reconciliation. Incorporating local perceptions of landscape dynamics as basis for such negotiations is particularly relevant for sub-Saharan Africa, where most people depend on natural ecosystems for livelihoods and well-being. This study applied participatory scenario building and spatially explicit simulation to unravel perceptions of the potential impact of rubber and settlement expansion on the provision of selected ecosystem services in southwestern Ghana under a business-as-usual scenario. We collected data in workshops and expert surveys on locally relevant ecosystem services, their indicator values, and the probable land-use transitions. The data was translated into an assessment matrix and integrated into a spatially explicit modeling platform, allowing visualization and comparison of the impact on ecosystem service provision of land-use scenarios under rubber plantation and settlement expansion. The results show the capacity of current (2020) and future land-use patterns to provide locally relevant ecosystem services, indicating a decline in capacity of ecosystem service provisioning in the future compared to the 2020 land-use patterns, a threat to the benefits humans derive from ecosystems. This highlights urgent need for policies and measures to control the drivers of land-use/land-cover change. Furthermore, the results emphasize the importance of diversifying land-use/land-cover types for sustainable landscape development. The paper contributes new insights into how spatially explicit and semi-quantitative methods can make stakeholder perceptions of landscape dynamics explicit as a basis for implementing integrated landscape approaches.Peer Reviewe
Idea generation in exploitative and explorative business process redesign techniques
No full textBusiness process redesign has received considerable attention in research and practice. An important task contributing to redesign is idea generation. It has been argued that the choice of technique influences redesign outcomes, but empirical evidence is largely missing. In this paper, we examine the role of idea generation in business process redesign by comparing two different kinds of techniques: exploitative and explorative redesign techniques. Often, exploitative techniques are expected to yield more appropriate solutions, while explorative techniques are associated with more creative outcomes. To investigate such propositions, we consider the Best Practices of Process Redesign as an example of an exploitative redesign technique and the Business Process Design Space as an explorative redesign technique. We conducted a free-simulation experiment to study the empirical impact of the choice of redesign techniques on outcomes. We find that the Business Process Design Space leads to a higher number of redesign ideas, which are also more diverse. These are more creative and novel than ideas produced by the Best Practices of Process Redesign. Against expectation, the best practices as an exploitative approach do not produce more appropriate nor impactful ideas in our task design. Since both approaches cover different areas of improvement, a key implication of our work is that they should not be seen as isolated approaches to redesign; rather, they should be purposefully combined to not only create novel but also operational business process redesigns.Peer Reviewe
Spatially resolved emulated annual temperature projections for overshoot pathways
No full textDue to insufficient climate action over the past decade, it is increasingly likely that 1.5 °C of global warming will be exceeded – at least temporarily – in the 21 st century. Such a temporary temperature overshoot carries additional climate risks which are poorly understood. Earth System Model climate projections are only available for a very limited number of overshoot pathways, thereby preventing comprehensive analysis of their impacts. Here, we address this issue by presenting a novel dataset of spatially resolved emulated annual temperature projections for different overshoot pathways. The dataset was created using the FaIR and MESMER emulators. First, FaIR was employed to translate ten different emission scenarios, including seven that are characterised by overshoot, into a large ensemble of forced global mean temperatures. These global mean temperatures were then converted into stochastic ensembles of local annual temperature fields using MESMER. To ensure an optimal tradeoff between accurate characterization of the ensemble spread and storage requirements for large ensembles, this procedure was accompanied by testing the sensitivity of sample quantiles to different ensemble sizes. The resulting dataset offers the unique opportunity to study local and regional climate change impacts of a range of overshoot scenarios, including the timing and magnitude of temperature thresholds exceedance.Peer Reviewe
A defense of Isaacson’s thesis, or how to make sense of the boundaries of finite mathematics
No full textDaniel Isaacson has advanced an epistemic notion of arithmetical truth according to which the latter is the set of truths that we grasp on the basis of our understanding of the structure of natural numbers alone. Isaacson’s thesis is then the claim that Peano Arithmetic ( PA ) is the theory of finite mathematics, in the sense that it proves all and only arithmetical truths thus understood. In this paper, we raise a challenge for the thesis and show how it can be overcome. We introduce the concept of purity for theories of arithmetic: a theory of arithmetic is pure when it only proves arithmetical truths. Then, we argue that, under Isaacson’s thesis, some PA -provable truths—including transfinite induction claims for infinite ordinals and some consistency statements—are seemingly not arithmetical in Isaacson’s sense, and hence that Isaacson’s thesis might entail the impurity of PA . Nonetheless, we conjecture that the advocate of Isaacson’s thesis can avoid this undesirable consequence: the arithmetical nature, as understood by Isaacson, of all contentious PA -provable statements can be justified. As a case study, we explore how this is done for transfinite induction claims with infinite ordinals below ε0. To this end, we show that the PA-proof of such claims employs exclusively resources from finite mathematics, and that ordinals below ε0are finitary objects despite being infinite.Arts and Humanities Research Councilhttp://dx.doi.org/10.13039/501100000267Peer Reviewe
From a cultural to a distributive issue: Public climate action as a new field for comparative political economy
No full textThis article reviews recent insights from the blooming Comparative Political Economy (CPE) literature on climate change with the aim to demonstrate the importance of integrating climate change into the field of CPE and to highlight the contributions of CPE to our understanding of the social and political obstacles to effective climate policies. In addition, we advance two key points to bring the CPE literature forward. To tighten the dialogue between the “electoral politics” and “interest group politics” approaches, we propose understanding climate politics as a triadic conflict between losers of climate change, losers of public climate action (PCA), and winners of PCA. Second, we argue that the scope of CPE studies needs expansion. While existing CPE literature predominantly focuses on climate change mitigation, it is essential to consider climate change adaptation due to its significant distributive implications at the macro‐ and micro‐levels of societies.Peer Reviewe
Identifying Major Factors for Success and Failure of Conservation Programs in Europe
No full textIn Europe, various conservation programs adopted to maintain or restore biodiversity have experienced differing levels of success. However, a synthesis about major factors for success of biodiversity-related conservation programs across ecosystems and national boundaries, such as incentives, subsidies, enforcement, participation, or spatial context, is missing. Using a balanced scorecard survey among experts, we analyzed and compared factors contributing to success or failure of three different conservation programs: two government programs (Natura 2000 and the ecological measures of the Water Framework Directive) and one conservation program of a non-governmental organization (NGO; Rewilding Europe), all focusing on habitat and species conservation. The experts perceived the NGO program as more successful in achieving biodiversity-related aims than governmental conservation legislation. Among the factors perceived to influence the success of biodiversity conservation, several stood out: Biodiversity-damaging subsidies, external economic interests competing with conservation goals or policies conflicting with biodiversity conservation were recognized as major factors for the lack of conservation success. Outreach to raise societal interest and awareness as well as stakeholder involvement were perceived as closely related to the success of programs. Our expert survey demonstrated that external factors from economy and policy often hinder success of conservation programs, while societal and environmental factors rather contribute to it. This study implies that conservation programs should be designed to be as inclusive as possible and provides a basis for developing a standardized methodology that explicitly considers indirect drivers from areas such as economy, policy and society.Bundesministerium für Bildung und Forschunghttp://dx.doi.org/10.13039/501100002347Deutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Villum Fondenhttp://dx.doi.org/10.13039/100008398Danmarks Grundforskningsfondhttp://dx.doi.org/10.13039/501100001732Leibniz-Gemeinschafthttp://dx.doi.org/10.13039/501100001664Peer Reviewe