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The region of the Andean back-arc of northwestern Argentina has been struck by several magnitude >= 6 crustal earthquakes since the first historically recorded event in 1692. One of these events corresponds to the Anta earthquake on 25 August 1948, with epicenter in the Santa Barbara System causing three deaths and severe damage in Salta and Jujuy provinces with maximum Modified Mercalli seismic intensities (MMI) of IX. We collected and digitized analog seismograms of this earthquake from worldwide seismic observatories in order to perform first-motion analysis and modeling of long-period teleseismic P-waveforms. Our results indicate a simple seismic source of M0 = 2.85 x 1019 N m consistent with a moment magnitude Mw = 6.9. We have also tested for the focal depth determining a shallow source at 8 km with a reverse focal mechanism solution with a minor dextral strike-slip component (strike 20 degrees, dip 30 degrees, rake 120 degrees) from the best fit of waveforms. Using magnitude size empirical relationships, the comparison of the obtained Mw 6.9 magnitude value and the ca. 10,000 km2 area of MMI >= IX from our seismic intensity map, which was obtained from newspaper and many historical reports, indicates a rupture length of 42 +/- 8 km for the Anta earthquake. We show our results in a 3D geological model around the epicentral area, which integrates modern seismicity, geological data, and information of a previously studied east-west cross section located a few kilometers south of the 1948 epicenter. The integration of all available information provides evidence of the re-activation of the Pie de la Sierra del Gallo fault during the 1948 Mw 6.9 shallow earthquake; this thrust fault bounds the Santa Barbara System along its western foothill.
We study the classical, two-sided stable marriage problem under pairwise preferences. In the most general setting, agents are allowed to express their preferences as comparisons of any two of their edges, and they also have the right to declare a draw or even withdraw from such a comparison. This freedom is then gradually restricted as we specify six stages of orderedness in the preferences, ending with the classical case of strictly ordered lists. We study all cases occurring when combining the three known notions of stability-weak, strong, and super-stability-under the assumption that each side of the bipartite market obtains one of the six degrees of orderedness. By designing three polynomial algorithms and two NP-completeness proofs, we determine the complexity of all cases not yet known and thus give an exact boundary in terms of preference structure between tractable and intractable cases.
How tone, intonation and emotion shape the development of infants' fundamental frequency perception
(2022)
Fundamental frequency (integral(0)), perceived as pitch, is the first and arguably most salient auditory component humans are exposed to since the beginning of life.
It carries multiple linguistic (e.g., word meaning) and paralinguistic (e.g., speakers' emotion) functions in speech and communication.
The mappings between these functions and integral(0) features vary within a language and differ cross-linguistically. For instance, a rising pitch can be perceived as a question in English but a lexical tone in Mandarin. Such variations mean that infants must learn the specific mappings based on their respective linguistic and social environments.
To date, canonical theoretical frameworks and most empirical studies do not view or consider the multi-functionality of integral(0), but typically focus on individual functions. More importantly, despite the eventual mastery of integral(0) in communication, it is unclear how infants learn to decompose and recognize these overlapping functions carried by integral(0). In this paper, we review the symbioses and synergies of the lexical, intonational, and emotional functions that can be carried by integral(0) and are being acquired throughout infancy.
On the basis of our review, we put forward the Learnability Hypothesis that infants decompose and acquire multiple integral(0) functions through native/environmental experiences. Under this hypothesis, we propose representative cases such as the synergy scenario, where infants use visual cues to disambiguate and decompose the different integral(0) functions. Further, viable ways to test the scenarios derived from this hypothesis are suggested across auditory and visual modalities.
Discovering how infants learn to master the diverse functions carried by integral(0) can increase our understanding of linguistic systems, auditory processing and communication functions.
Quenching mechanism of uranyl(VI) by chloride and bromide in aqueous and non-aqueous solutions
(2021)
A major hindrance in utilizing uranyl(VI) luminescence as a standard analytical tool, for example, in environmental monitoring or nuclear industries, is quenching by other ions such as halide ions, which are present in many relevant matrices of uranyl(VI) speciation. Here, we demonstrate through a combination of time-resolved laser-induced fluorescence spectroscopy, transient absorption spectroscopy, and quantum chemistry that coordinating solvent molecules play a crucial role in U(VI) halide luminescence quenching. We show that our previously suggested quenching mechanism based on an internal redox reaction of the 1:2-uranyl-halide-complex holds also true for bromide-induced quenching of uranyl(VI). By adopting specific organic solvents, we were able to suppress the separation of the oxidized halide ligand X-2(center dot-) and the formed uranyl(V) into fully solvated ions, thereby "reigniting" U(VI) luminescence. Time-dependent density functional theory calculations show that quenching occurs through the outer-sphere complex of U(VI) and halide in water, while the ligand-to-metal charge transfer is strongly reduced in acetonitrile.
Since the beginning of the Anthropocene, lacustrine biodiversity has been influenced by climate change and human activities. These factors advance the spread of harmful cyanobacteria in lakes around the world, which affects water quality and impairs the aquatic food chain. In this study, we assessed changes in cyanobacterial community dynamics via sedimentary DNA (sedaDNA) from well-dated lake sediments of Lake Tiefer See, which is part of the Klocksin Lake Chain spanning the last 350 years. Our diversity and community analysis revealed that cyanobacterial communities form clusters according to the presence or absence of varves. Based on distance-based redundancy and variation partitioning analyses (dbRDA and VPA) we identified that intensified lake circulation inferred from vegetation openness reconstructions, delta C-13 data (a proxy for varve preservation) and total nitrogen content were abiotic factors that significantly explained the variation in the reconstructed cyanobacterial community from Lake Tiefer See sediments. Operational taxonomic units (OTUs) assigned to Microcystis sp. and Aphanizomenon sp. were identified as potential eutrophication-driven taxa of growing importance since circa common era (ca. CE) 1920 till present. This result is corroborated by a cyanobacteria lipid biomarker analysis. Furthermore, we suggest that stronger lake circulation as indicated by non-varved sediments favoured the deposition of the non-photosynthetic cyanobacteria sister clade Sericytochromatia, whereas lake bottom anoxia as indicated by subrecent- and recent varves favoured the Melainabacteria in sediments. Our findings highlight the potential of high-resolution amplicon sequencing in investigating the dynamics of past cyanobacterial communities in lake sediments and show that lake circulation, anoxic conditions, and human-induced eutrophication are main factors explaining variations in the cyanobacteria community in Lake Tiefer See during the last 350 years.
How different are the results of constant-rate resetting of anomalous-diffusion processes in terms of their ensemble-averaged versus time-averaged mean-squared displacements (MSDs versus TAMSDs) and how does stochastic resetting impact nonergodicity? We examine, both analytically and by simulations, the implications of resetting on the MSD- and TAMSD-based spreading dynamics of particles executing fractional Brownian motion (FBM) with a long-time memory, heterogeneous diffusion processes (HDPs) with a power-law space-dependent diffusivity D(x) = D0|x|gamma and their "combined" process of HDP-FBM. We find, inter alia, that the resetting dynamics of originally ergodic FBM for superdiffusive Hurst exponents develops disparities in scaling and magnitudes of the MSDs and mean TAMSDs indicating weak ergodicity breaking. For subdiffusive HDPs we also quantify the nonequivalence of the MSD and TAMSD and observe a new trimodal form of the probability density function. For reset FBM, HDPs and HDP-FBM we compute analytically and verify by simulations the short-time MSD and TAMSD asymptotes and long-time plateaus reminiscent of those for processes under confinement. We show that certain characteristics of these reset processes are functionally similar despite a different stochastic nature of their nonreset variants. Importantly, we discover nonmonotonicity of the ergodicitybreaking parameter EB as a function of the resetting rate r. For all reset processes studied we unveil a pronounced resetting-induced nonergodicity with a maximum of EB at intermediate r and EB similar to(1/r )-decay at large r. Alongside the emerging MSD-versus-TAMSD disparity, this r-dependence of EB can be an experimentally testable prediction. We conclude by discussing some implications to experimental systems featuring resetting dynamics.
Our input is a complete graph G on n vertices where each vertex has a strict ranking of all other vertices in G. The goal is to construct a matching in G that is popular. A matching M is popular if M does not lose a head-to-head election against any matching M ': here each vertex casts a vote for the matching in {M,M '} in which it gets a better assignment. Popular matchings need not exist in the given instance G and the popular matching problem is to decide whether one exists or not. The popular matching problem in G is easy to solve for odd n. Surprisingly, the problem becomes NP-complete for even n, as we show here. This is one of the few graph theoretic problems efficiently solvable when n has one parity and NP-complete when n has the other parity.
In-depth understanding of the reorganization of the hydrological cycle in response to global climate change is crucial in highly sensitive regions like the eastern Mediterranean, where water availability is a major factor for socioeconomic and political development.
The sediments of Lake Lisan provide a unique record of hydroclimatic change during the last glacial to Holocene transition (ca. 24-11 ka) with its tremendous water level drop of similar to 240 m that finally led to its transition into the present hypersaline water body-the Dead Sea.
Here we utilize high-resolution sedimentological analyses from the marginal terraces and deep lake to reconstruct an unprecedented seasonal record of the last millennia of Lake Lisan. Aragonite varve formation in intercalated intervals of our record demonstrates that a stepwise long-term lake level decline was interrupted by almost one millennium of rising or stable water level.
Even periods of pronounced water level drops indicated by gypsum deposition were interrupted by decades of positive water budgets.
Our results thus highlight that even during major climate change at the end of the last glacial, decadal to millennial periods of relatively stable or positive moisture supply occurred which could have been an important premise for human sedentism.
We establish a new approach of treating elliptic boundary value problems (BVPs) on manifolds with boundary and regular corners, up to singularity order 2. Ellipticity and parametrices are obtained in terms of symbols taking values in algebras of BVPs on manifolds of corresponding lower singularity orders. Those refer to Boutet de Monvel's calculus of operators with the transmission property, see Boutet de Monvel (Acta Math 126:11-51, 1971) for the case of smooth boundary. On corner configuration operators act in spaces with multiple weights. We mainly study the case of upper left entries in the respective 2 x 2 operator block-matrices of such a calculus. Green operators in the sense of Boutet de Monvel (Acta Math 126:11-51, 1971) analogously appear in singular cases, and they are complemented by contributions of Mellin type. We formulate a result on ellipticity and the Fredholm property in weighted corner spaces, with parametrices of analogous kind.
Comparative vote switching
(2024)
Large literatures focus on voter reactions to parties’ policy strategies, agency, or legislative performance. While many inquiries make explicit assumptions about the direction and magnitude of voter flows between parties, comparative empirical analyses of vote switching remain rare. In this article, we overcome three challenges that have previously impeded the comparative study of dynamic party competition based on voter flows: we present a novel conceptual framework for studying voter retention, defection, and attraction in multiparty systems, showcase a newly compiled data infrastructure that marries comparative vote switching data with information on party behavior and party systems in over 250 electoral contexts, and introduce a statistical model that renders our conceptual framework operable. These innovations enable first-time inquiries into the polyadic vote switching patterns underlying multiparty competition and unlock major research potentials on party competition and party system change.
Public opinion polls have become vital and increasingly visible parts of election campaigns. Previous research has frequently demonstrated that polls can influence both citizens' voting intentions and political parties' campaign strategies. However, they are also fraught with uncertainty. Margins of error can reflect (parts of) this uncertainty. This paper investigates how citizens' voting intentions change due to whether polling estimates are presented with or without margins of error.
Using a vignette experiment (N=3224), we examine this question based on a real-world example in which different election polls were shown to nationally representative respondents ahead of the 2021 federal election in Germany. We manipulated the display of the margins of error, the interpretation of polls and the closeness of the electoral race.
The results indicate that margins of error can influence citizens' voting intentions. This effect is dependent on the actual closeness of the race and additional interpretative guidance provided to voters. More concretely, the results consistently show that margins of error increase citizens' inclination to vote for one of the two largest contesting parties if the polling gap between these parties is small, and an interpretation underlines this closeness.
The findings of this study are important for three reasons. First, they help to determine whether margins of error can assist citizens in making more informed (strategic) vote decisions. They shed light on whether depicting opinion-poll uncertainty affects the key features of representative democracy, such as democratic accountability. Second, the results stress the responsibility of the media. The way polls are interpreted and contextualized influences the effect of margins of error on voting behaviour. Third, the findings of this paper underscore the significance of including methodological details when communicating scientific research findings to the broader public.
In the Shadow of Ukraine
(2022)
In 2022, India captured global attention over its response to the war in Ukraine. While calling for both parties' return to diplomacy, India abstained from several United Nations resolutions condemning Russian aggression. For a country that ostensibly subscribes to the values of democracy and territorial integrity, its response appeared frustrating and contradictory, but it is broadly consistent with its long-standing policy of non-alignment. Although India's relationship with China is increasingly contentious, New Delhi is not yet fully convinced that it is in India's interest to swing westwards. The country's relations with Russia and China are deep, complex and substantive. In addition to the military and economic benefits it derives from its connection with Russia, New Delhi and Moscow share an avowed preference for a more equal, multipolar world. India will eventually have to reflect on the extent to which it can sustain its balancing act.
§§ 327-327u
(2023)
Non-Markovian diffusion of excitons in layered perovskites and transition metal dichalcogenides
(2022)
The diffusion of excitons in perovskites and transition metal dichalcogenides shows clear anomalous, subdiffusive behaviour in experiments.
In this paper we develop a non-Markovian mobile-immobile model which provides an explanation of this behaviour through paired theoretical and simulation approaches.
The simulation model is based on a random walk on a 2D lattice with randomly distributed deep traps such that the trapping time distribution involves slowly decaying power-law asymptotics.
The theoretical model uses coupled diffusion and rate equations for free and trapped excitons, respectively, with an integral term responsible for trapping.
The model provides a good fitting of the experimental data, thus, showing a way for quantifying the exciton diffusion dynamics.
To date, sex and gender differences play only a minor role in medical research and practice, thereby putting individuals’ health at risk. Gender-specific medicine, or the practice of taking these differences into account when conducting research and treating patients so far is being discussed primarily by experts. With people increasingly using social media such as Twitter for sharing and searching for health-related information online, Twitter can potentially educate about gender-specific medicine. However, little is known about the information circulation and the structure of interactions on the Twitter network discussing this topic. Results of a network analysis show that the network exhibits a community-structure, with information exchange being limited and concentrated in silos. This indicates that there is untapped potential for acquiring new information by users through interacting with individuals outside their community. Public health officials may benefit from this insight and tailor online campaigns to enhance awareness on gender-specific medicine.
Inorganic perovskite solar cells show excellent thermal stability, but the reported power conversion efficiencies are still lower than for organic-inorganic perovskites. This is mainly caused by lower open-circuit voltages (V(OC)s). Herein, the reasons for the low V-OC in inorganic CsPbI2Br perovskite solar cells are investigated. Intensity-dependent photoluminescence measurements for different layer stacks reveal that n-i-p and p-i-n CsPbI2Br solar cells exhibit a strong mismatch between quasi-Fermi level splitting (QFLS) and V-OC. Specifically, the CsPbI2Br p-i-n perovskite solar cell has a QFLS-e center dot V-OC mismatch of 179 meV, compared with 11 meV for a reference cell with an organic-inorganic perovskite of similar bandgap. On the other hand, this study shows that the CsPbI2Br films with a bandgap of 1.9 eV have a very low defect density, resulting in an efficiency potential of 20.3% with a MeO-2PACz hole-transporting layer and 20.8% on compact TiO2. Using ultraviolet photoelectron spectroscopy measurements, energy level misalignment is identified as a possible reason for the QFLS-e center dot V-OC mismatch and strategies for overcoming this V-OC limitation are discussed. This work highlights the need to control the interfacial energetics in inorganic perovskite solar cells, but also gives promise for high efficiencies once this issue is resolved.
Quantifying root water uptake is essential to understanding plant water use and responses to different environmental conditions. However, non-destructive measurement of water transport and related hydraulics in the soil-root system remains a challenge.
Neutron imaging, with its high sensitivity to hydrogen, has become an unparalleled tool to visualize and quantify root water uptake in vivo. In combination with isotopes (e.g., deuterated water) and a diffusion-convection model, root water uptake and hydraulic redistribution in root and soil can be quantified.
Here, we review recent advances in utilizing neutron imaging to visualize and quantify root water uptake, hydraulic redistribution in roots and soil, and root hydraulic properties of different plant species.
Under uniform soil moisture distributions, neutron radiographic studies have shown that water uptake was not uniform along the root and depended on both root type and age. For both tap (e.g., lupine [Lupinus albus L.]) and fibrous (e.g., maize [Zea mays L.]) root systems, water was mainly taken up through lateral roots. In mature maize, the location of water uptake shifted from seminal roots and their laterals to crown/nodal roots and their laterals.
Under non-uniform soil moisture distributions, part of the water taken up during the daytime maintained the growth of crown/nodal roots in the upper, drier soil layers. Ultra-fast neutron tomography provides new insights into 3D water movement in soil and roots. We discuss the limitations of using neutron imaging and propose future directions to utilize neutron imaging to advance our understanding of root water uptake and soil-root interactions.
Die Nutzung von Informations- und Kommunikationstechnik (IKT), Fachverfahren und die Automatisierung von Prozessen verändern die Sachbearbeitung und Leistungserstellung in der Verwaltung und somit die Tätigkeiten, Arbeitsbedingungen und Personalstrukturen. Bei der Antragsbearbeitung und Bescheiderstellung in der Ordnungs- und Leistungsverwaltung erhält IKT nicht nur eine unterstützende, sondern zunehmend auch eine leitende oder entscheidende Rolle. Abhängig von der konkreten Ausgestaltung kann die fortschreitende Digitalisierung eine ganzheitliche Sachbearbeitung ermöglichen, aber auch einschränken. Insgesamt kann sie zu einer Neuordnung des Berufsfeldes öffentlicher Dienst führen.
The growing use of digital tools in policy implementation has altered the work of street-level bureaucrats who are granted substantial discretionary power in decision-making. Digital tools can constrain discretionary power, like the curtailment thesis proposed, or serve as action resources, like the enablement thesis suggested. This article assesses empirical evidence of the impact of digital tools on street-level work and decision-making in service-oriented and regulation-oriented organisations based on a systematic literature review and thematic qualitative content analysis of 36 empirical studies published until 2021. The findings demonstrate different effects with regard to the role of digital tools and the core tasks of the public administration, depending on political and managerial goals and consequent system design. Leading or decisive digital tools mostly curtail discretion, especially in service-oriented organisations. In contrast, an enhanced information base or recommendations for actions enable decision-making, in particular in regulation-oriented organisations. By showing how street-level bureaucrats actively try to resist the curtailing effects caused by rigid design to address individual circumstances, for instance by establishing ways of coping like rule bending or rule breaking, using personal resources or prioritising among clients, this study demonstrates the importance of the continuation thesis and the persistently crucial role of human judgement in policy implementation.
Schools are key contexts for the development of adolescents' critical consciousness. We explored how three dimensions of the classroom cultural diversity climate (critical consciousness, color-evasion, and multiculturalism) related to adolescents' critical reflection (i.e., perceived societal Islamophobia) and intended critical action (i.e., political activism). Our sample included adolescents experiencing high (second generation, Muslim, N = 237) versus low (non-immigrant descent, non-Muslim, N = 478) stigmatization in Germany. Multilevel analyses revealed that for both groups a critical consciousness climate, but not a color-evasive or a multicultural climate, was positively associated with perceived societal Islamophobia and intended critical action. Thus, to promote adolescents' critical consciousness, schools should go beyond emphasizing a common humanity and celebrating cultural diversity and include explicit discussions of social inequity.
Ground motion with strong-velocity pulses can cause significant damage to buildings and structures at certain periods; hence, knowing the period and velocity amplitude of such pulses is critical for earthquake structural engineering.
However, the physical factors relating the scaling of pulse periods with magnitude are poorly understood.
In this study, we investigate moderate but damaging earthquakes (M-w 6-7) and characterize ground- motion pulses using the method of Shahi and Baker (2014) while considering the potential static-offset effects.
We confirm that the within-event variability of the pulses is large. The identified pulses in this study are mostly from strike-slip-like earthquakes. We further perform simulations using the freq uency-wavenumber algorithm to investigate the causes of the variability of the pulse periods within and between events for moderate strike-slip earthquakes.
We test the effect of fault dips, and the impact of the asperity locations and sizes. The simulations reveal that the asperity properties have a high impact on the pulse periods and amplitudes at nearby stations.
Our results emphasize the importance of asperity characteristics, in addition to earthquake magnitudes for the occurrence and properties of pulses produced by the forward directivity effect.
We finally quantify and discuss within- and between-event variabilities of pulse properties at short distances.
We consider an array of nearest-neighbor coupled nonlinear autonomous oscillators with quenched ran-dom frequencies and purely conservative coupling. We show that global phase-locked states emerge in finite lattices and study numerically their destruction. Upon change of model parameters, such states are found to become unstable with the generation of localized periodic and chaotic oscillations. For weak nonlinear frequency dispersion, metastability occur akin to the case of almost-conservative systems. We also compare the results with the phase-approximation in which the amplitude dynamics is adiabatically eliminated.
The Arctic is rich in aquatic systems and experiences rapid warming due to climate change. The accelerated warming causes permafrost thaw and the mobilization of organic carbon.
When dissolved organic carbon is mobilized, this DOC can be transported to aquatic systems and degraded in the water bodies and further downstream. Here, we analyze the influence of different landscape components on DOC concentrations and export in a small (6.45 km(2)) stream catchment in the Lena River Delta.
The catchment includes lakes and ponds, with the flow path from Pleistocene yedoma deposits across Holocene non-yedoma deposits to the river outlet. In addition to DOC concentrations, we use radiocarbon dating of DOC as well as stable oxygen and hydrogen isotopes (delta O-18 and delta D) to assess the origin of DOC.
We find significantly higher DOC concentrations in the Pleistocene yedoma area of the catchment compared to the Holocene non-yedoma area with medians of 5 and 4.5 mg L-1 (p < 0.05), respectively. When yedoma thaw streams with high DOC concentration reach a large yedoma thermokarst lake, we observe an abrupt decrease in DOC concentration, which we attribute to dilution and lake processes such as mineralization. The DOC ages in the large thermokarst lake (between 3,428 and 3,637 C-14 y BP) can be attributed to a mixing of mobilized old yedoma and Holocene carbon.
Further downstream after the large thermokarst lake, we find progressively younger DOC ages in the stream water to its mouth, paired with decreasing DOC concentrations. This process could result from dilution with leaching water from Holocene deposits and/or emission of ancient yedoma carbon to the atmosphere. Our study shows that thermokarst lakes and ponds may act as DOC filters, predominantly by diluting incoming waters of higher DOC concentrations or by re-mineralizing DOC to CO2 and CH4.
Nevertheless, our results also confirm that the small catchment still contributes DOC on the order of 1.2 kg km(-2) per day from a permafrost landscape with ice-rich yedoma deposits to the Lena River.
Microbe-mediated enzymatic hydrolysis of organic matter entails the production of hydrolysate, the recovery of which may be more or less efficient. The selfish uptake mechanism, recently discovered, allows microbes to hydrolyze polysaccharides and take up large oligomers, which are then degraded in the periplasmic space. By minimizing the hydrolysate loss, selfish behaviour may be profitable for free-living cells dwelling in a patchy substrate landscape. However, selfish uptake seems to be tailored to algal-derived polysaccharides, abundant in organic particles, suggesting that particle-attached microbes may use this strategy. We tracked selfish polysaccharides uptake in surface microbial communities of the northeastern Mediterranean Sea, linking the occurrence of this processing mode with microbial lifestyle. Additionally, we set up fluorescently labelled polysaccharides incubations supplying phytodetritus to investigate a 'pioneer' scenario for particle-attached microbes. Under both conditions, selfish behaviour was almost exclusively carried out by particle-attached microbes, suggesting that this mechanism may represent an advantage in the race for particle exploitation. Our findings shed light on the selfish potential of particle-attached microbes, suggesting multifaceted foraging strategies exerted by particle colonizers.
Same but different
(2022)
The peace processes in Liberia and Sierra Leone share similar contexts and have an interrelated history. They are also often portrayed as successful cases of peacebuilding. This conclusion seems valid, as war has not returned, and political power was handed over peacefully; however, both cases differ with regard to the inclusiveness of the peace processes and the role of local leaders. This article aims to add to the critical peacebuilding debate by focusing on local perceptions about the position of local leaders in these two peace processes. We conducted a public opinion survey in five regions in Sierra Leone and Liberia and expert interviews with peacebuilding actors to examine changing perceptions about the roles of local leaders in both countries. This article speaks to the broader peacebuilding debate by highlighting the importance of including local voices in the peace process and by discussing challenges of inclusive peacebuilding.
In which negotiation contexts are transitional justice provisions included in peace agreements? Today, many peace agreements include transitional justice provisions, but their inclusion differs based on conflict and negotiation characteristics. While context thus seems to be relevant for the choice of transitional justice provisions agreed on by the warring parties, very little is known about the context clusters that enable transitional justice. Using data on 58 full peace agreements signed between 1989 and 2018, a crisp-set Qualitative Comparative Analysis (QCA) investigates the combinations of conflict intensity, rebel group strength, type of conflict, third-party support and civil society participation that led to the inclusion of transitional justice provisions. The result of this exploratory study suggests four context settings that are identified as being empirically relevant for the inclusion of transitional justice provisions. Choices of justice are thus the result of an overall negotiation environment characterized by multiple interrelated context factors.
Wem wird geglaubt und wem nicht? Wessen Wissen wird weitergegeben und wessen nicht? Wer hat eine Stimme und wer nicht? Theorien der epistemischen Ungerechtigkeit befassen sich mit dem breiten Feld der ungerechten oder unfairen Behandlung, die mit Fragen des Wissens, Verstehens und Kommunizierens zusammenhängen, wie z.B. die Möglichkeit, vom Wissen oder von kommunikativen Praktiken ausgeschlossen zu werden oder zum Schweigen gebracht zu werden, aber auch Kontexte, in denen die Bedeutungen mancher systematisch verzerrt oder falsch gehört und falsch dargestellt werden, in denen manchen misstraut wird oder es an epistemischer Handlungsfähigkeit mangelt. In diesem Buch wird eine Übersicht über die breite Debatte epistemischer Ungerechtigkeit, epistemischer Unterdrückung und epistemischer Gewalt gegeben, in dem unterschiedliche Theorien, die sich auf der Schnittstelle von Gerechtigkeitstheorie und epistemischen Fragen befinden, systematisch und kritisch diskutiert sowie theoretische Vorgänger dieser Theorien beleuchtet werden.
Reviewed Publications:
Garcia Manon. Wir werden nicht unterwürfig geboren. Wie das Patriarchat das Leben von Frauen bestimmt. Berlin: Suhrkamp, 2021, 235 S.
Hay Carol. Think like a Feminist. The Philosophy behind the Revolution. New York: W. W. Norton & Company, 2020, 222 S.
Manne Kate. Entitled. How Male Privilege Hurts Women. London: Allen Lane, 2020, 270 S.
Srinivasan Amia. The Right to Sex. London: Bloomsbury, 2021, 279 S.
Der vorliegende Beitrag, der sich weniger als Fachbeitrag, sondern vielmehr als Erfahrungsbericht aus der Praxis versteht, berichtet von unterschiedlichen Versuchen, die Mensch-Tier-Beziehung in den schulischen Kontext einzubringen und somit der unzureichenden Beachtung der Thematik entgegenzuwirken. Nachdem überblicksartig die Relevanz der Mensch-Tier-Thematik herausgestellt und auf diese Weise die Notwendigkeit einer unterrichtlichen Beschäftigung mit dem Verhältnis von Menschen und anderen Tieren begründet wird, wird zunächst von einem ersten Versuch berichtet, (angehende) Lehrkräfte im Rahmen eines Workshops am Studienseminar Potsdam für die Relevanz der Mensch-Tier-Thematik zu sensibilisieren sowie über eine mögliche Umsetzung in den verschiedenen Unterrichtsfächern zu informieren. Anschließend werden – exemplarisch für den Politikunterricht – zwei Unterrichtsstunden, die die Mensch-Tier-Beziehung auf verschiedene Weise in den Politikunterricht einbeziehen, sowie die im Rahmen der Durchführung gesammelten Erfahrungen vorgestellt.
Colloidal metal sulfide nanoparticles for high performance electrochemical energy storage systems
(2022)
Transition metal sulfides have emerged as excellent replacement candidates of traditional insertion electrode materials based on their conversion or alloying mechanisms, facilitating high specific capacity and rate ability. However, parasitic reactions such as massive volume change during the discharge/ charge processes, intermediate polysulfide dissolution, and passivating solid electrolyte interface formation have led to poor cyclability, hindering their feasibility and applicability in energy storage systems. Colloidal metal sulfide nanoparticles, a special class that integrates the intrinsic chemical properties of metal sulfides and their specified structural features, have fairly enlarged their contribution due to the synergistic effect. This review highlights the latest synthetic approaches based on colloidal process. Their corresponding electrochemical outcomes will also be discussed, which are thoroughly updated along with their insight scientific standpoints.
Consumers are increasingly demanding higher quality and safety standards for the products they consume, and one of this is wheat flour, the basis of a wide variety of processed products. This major component in the diet of many communities can be contaminated by microorganisms before the grain harvest, or during the grain storage right before processing. These microorganisms include several fungal species, many of which produce mycotoxins, secondary metabolites that can cause severe acute and chronic disorders. Yet, we still know little about the overall composition of fungal communities associated with wheat flour. In this study, we contribute to fill this gap by characterizing the fungal microbiome of different types of wheat flour using culture-dependent and -independent techniques. Qualitatively, these approaches suggested similar results, highlighting the presence of several fungal taxa able to produce mycotoxins. In-vitro isolation of fungal species suggest a higher frequency of Penicillium, while metabarcoding suggest a higher abundance of Alternaria. This discrepancy might reside on the targeted portion of the community (alive vs. overall) or in the specific features of each technique. Thus, this study shows that commercial wheat flour hosts a wide fungal diversity with several taxa potentially representing concerns for consumers, aspects that need more attention throughout the food production chain.
Effect of magnesium salts with chaotropic anions on the swelling behavior of PNIPMAM thin films
(2023)
Poly(N-isopropylmethacrylamide) (PNIPMAM) is a stimuli responsive polymer, which in thin film geometry exhibits a volume-phase transition upon temperature increase in water vapor. The swelling behavior of PNIPMAM thin films containing magnesium salts in water vapor is investigated in view of their potential application as nanodevices. Both the extent and the kinetics of the swelling ratio as well as the water content are probed with in situ time-of-flight neutron reflectometry. Additionally, in situ Fourier-transform infrared (FTIR) spectroscopy provides information about the local solvation of the specific functional groups, while two-dimensional FTIR correlation analysis further elucidates the temporal sequence of solvation events. The addition of Mg(ClO4)2 or Mg(NO3)2 enhances the sensitivity of the polymer and therefore the responsiveness of switches and sensors based on PNIPMAM thin films. It is found that Mg(NO3)2 leads to a higher relative water uptake and therefore achieves the highest thickness gain in the swollen state.
In Decolonizing Universalism: A Transnational Feminist Ethic zielt Serene Khader auf eine Neuausrichtung der feministischen Perspektive, welche es schafft, dekolonial und anti-imperialistisch zu sein, ohne gleichzeitig dem Universalismus komplett abzuschwören. Die Motivation hinter dieser Neuorientierung ist die Einsicht, dass der liberale moralische Universalismus oftmals kulturelle Vorherrschaft und Imperialismus verstärkt. In diesem Kommentar wollen wir (a) uns mit der Frage beschäftigen, was genau unter Geschlechtergerechtigkeit verstanden werden soll und welcher Maßstab zur Beantwortung der Frage nach Gerechtigkeit angebracht ist und (b) einige Ideen zum Unterschied zwischen idealer und nicht-idealer Theorie liefern.
Thermal electrons have gyroradii many orders of magnitude smaller than the finite width of a shock, thus need to be pre-accelerated before they can cross it and be accelerated by diffusive shock acceleration. One region where pre-acceleration may occur is the inner foreshock, which upstream electrons must pass through before any potential downstream crossing. In this paper, we perform a large-scale particle-in-cell simulation that generates a single shock with parameters motivated from supernova remnants. Within the foreshock, reflected electrons excite the oblique whistler instability and produce electromagnetic whistler waves, which comove with the upstream flow and as nonlinear structures eventually reach radii of up to 5 ion-gyroradii. We show that the inner electromagnetic configuration of the whistlers evolves into complex nonlinear structures bound by a strong magnetic field around four times the upstream value. Although these nonlinear structures do not in general interact with cospatial upstream electrons, they resonate with electrons that have been reflected at the shock. We show that they can scatter, or even trap, reflected electrons, confining around 0.8% of the total upstream electron population to the region close to the shock where they can undergo substantial pre-acceleration. This acceleration process is similar to, yet approximately three times more efficient than, stochastic shock drift acceleration.
Dieser Band der Schriftenreihe der Badischen Heimat will im Rahmen der Vielzahl von Publikationen, die in diesem Jahr an den Beginn des Ersten Weltkrieges erinnern, einen besonderen Beitrag leisten. Gleichsam als „Geschichte von unten“ wirkend, gibt die vorliegende Sammlung der Feldpostbriefe einen gefilterten Eindruck in das Seelenleben der Kriegsgeneration wieder. Sie ist als Kollektion badischer Soldatenbriefe in dieser Form bisher einmalig und erweitert das Wahrnehmungsspektrum der scheinbar in weiter Ferne und dennoch so nah liegenden „Urkatastrophe“ um eine weitere wichtige Nuance.
Analyzing social wrongs
(2023)
In the debate on epistemic injustice, it is generally assumed that testimonial injustice as one form of epistemic injustice cannot be committed (fully) deliberately or intentionally because it involves unconscious identity prejudices. Drawing on the case of sexual violence against refugees in European refugee camps, this paper argues that there is a form of testimonial injustice—willful testimonial injustice—that is deliberate. To do so, the paper argues (a) that the hearer intentionally utilizes negative identity prejudices for a particular purpose and (b) that the hearer is aware of the fact that the intentionally used prejudices are in fact prejudices. Furthermore, the paper shows how testimonial injustice relates to recognition failures both in terms of a causal as well as a constitutive claim. In fact, introducing willful testimonial injustice can support the constitutive claim of such a relation that has so far received little attention. Besides arguing for a novel form of testimonial injustice and contributing to the recent debate on the relation between epistemic injustice and recognition failures, this paper is also motivated by the attempt to draw attention to the inhumane conditions for refugees at the border of Europe as well as elsewhere.
(Moralisch) guter Sex
(2023)
In einem kürzlich erschienenen Artikel argumentiert Almut v. Wedelstaedt überzeugend, warum Zustimmung zwar „die Bedingung für die Legitimation von Sex“ ist (2020, 127), dass die moralische Güte von Sex aber nur dann einzuschätzen ist, wenn wir darauf achten, ob die Beteiligten der Handlung sich auf Augenhöhe begegnen. Die Idee ist: Es gibt legitime sexuelle Handlungen, die moralisch gut sind, und es gibt legitime sexuelle Handlungen, die moralisch besser sind. Hier möchte ich die Idee des besseren Sexes genauer ausloten. Während v. Wedelstaedt von moralisch gelungenem Sex spricht und somit auf der Ebene der moralischen Bewertung von Sex bleibt, möchte ich die Frage danach stellen, was Sex qualitativ gut macht. Tatsächlich wird in der Zustimmungsdebatte meist davon ausgegangen, dass diese zwei Fragen wenig gemeinsam haben; ob eine sexuelle Handlung legitim ist, hat zunächst nichts damit zu tun, ob diese auch gut ist. Ich werde drei Argumente liefern, warum wir legitimen Sex und qualitativ guten Sex zusammen betrachten sollten – und es wird sich zeigen, dass die gegenwärtige philosophische und rechtstheoretische Debatte Zustimmung verkürzt diskutiert und daher alleingenommen wenig hilfreich ist, stattdessen benötigt die Zustimmungsdebatte auch eine Untersuchung von qualitativ gutem Sex.
Diglossic translanguaging
(2024)
This book examines how German-speaking Jews living in Berlin make sense and make use of their multilingual repertoire. With a focus on lexical variation, the book demonstrates how speakers integrate Yiddish and Hebrew elements into German for indexing belonging and for positioning themselves within the Jewish community. Linguistic choices are shaped by language ideologies (e.g., authenticity, prescriptivism, nostalgia). Speakers translanguage when using their multilingual repertoire, but do so in a diglossic way, using elements from different languages for specific domains
Wildfires, as a key disturbance in forest ecosystems, are shaping the world's boreal landscapes. Changes in fire regimes are closely linked to a wide array of environmental factors, such as vegetation composition, climate change, and human activity. Arctic and boreal regions and, in particular, Siberian boreal forests are experiencing rising air and ground temperatures with the subsequent degradation of permafrost soils leading to shifts in tree cover and species composition. Compared to the boreal zones of North America or Europe, little is known about how such environmental changes might influence long-term fire regimes in Russia. The larch-dominated eastern Siberian deciduous boreal forests differ markedly from the composition of other boreal forests, yet data about past fire regimes remain sparse. Here, we present a high-resolution macroscopic charcoal record from lacustrine sediments of Lake Khamra (southwest Yakutia, Siberia) spanning the last ca. 2200 years, including information about charcoal particle sizes and morphotypes. Our results reveal a phase of increased charcoal accumulation between 600 and 900 CE, indicative of relatively high amounts of burnt biomass and high fire frequencies. This is followed by an almost 900-year-long period of low charcoal accumulation without significant peaks likely corresponding to cooler climate conditions. After 1750 CE fire frequencies and the relative amount of biomass burnt start to increase again, coinciding with a warming climate and increased anthropogenic land development after Russian colonization. In the 20th century, total charcoal accumulation decreases again to very low levels despite higher fire frequency, potentially reflecting a change in fire management strategies and/or a shift of the fire regime towards more frequent but smaller fires. A similar pattern for different charcoal morphotypes and comparison to a pollen and non-pollen palynomorph (NPP) record from the same sediment core indicate that broad-scale changes in vegetation composition were probably not a major driver of recorded fire regime changes. Instead, the fire regime of the last two millennia at Lake Khamra seems to be controlled mainly by a combination of short-term climate variability and anthropogenic fire ignition and suppression.
Halide perovskites
(2021)
The spatio-temporal epidemic type aftershock sequence (ETAS) model is widely used to describe the self-exciting nature of earthquake occurrences. While traditional inference methods provide only point estimates of the model parameters, we aim at a fully Bayesian treatment of model inference, allowing naturally to incorporate prior knowledge and uncertainty quantification of the resulting estimates. Therefore, we introduce a highly flexible, non-parametric representation for the spatially varying ETAS background intensity through a Gaussian process (GP) prior. Combined with classical triggering functions this results in a new model formulation, namely the GP-ETAS model. We enable tractable and efficient Gibbs sampling by deriving an augmented form of the GP-ETAS inference problem. This novel sampling approach allows us to assess the posterior model variables conditioned on observed earthquake catalogues, i.e., the spatial background intensity and the parameters of the triggering function. Empirical results on two synthetic data sets indicate that GP-ETAS outperforms standard models and thus demonstrate the predictive power for observed earthquake catalogues including uncertainty quantification for the estimated parameters. Finally, a case study for the l'Aquila region, Italy, with the devastating event on 6 April 2009, is presented.
Relationships between climate, species composition, and species richness are of particular importance for understanding how boreal ecosystems will respond to ongoing climate change. This study aims to reconstruct changes in terrestrial vegetation composition and taxa richness during the glacial Late Pleistocene and the interglacial Holocene in the sparsely studied southeastern Yakutia (Siberia) by using pollen and sedimentary ancient DNA (sedaDNA) records. Pollen and sedaDNA metabarcoding data using the trnL g and h markers were obtained from a sediment core from Lake Bolshoe Toko. Both proxies were used to reconstruct the vegetation composition, while metabarcoding data were also used to investigate changes in plant taxa richness. The combination of pollen and sedaDNA approaches allows a robust estimation of regional and local past terrestrial vegetation composition around Bolshoe Toko during the last similar to 35,000 years. Both proxies suggest that during the Late Pleistocene, southeastern Siberia was covered by open steppe-tundra dominated by graminoids and forbs with patches of shrubs, confirming that steppe-tundra extended far south in Siberia. Both proxies show disturbance at the transition between the Late Pleistocene and the Holocene suggesting a period with scarce vegetation, changes in the hydrochemical conditions in the lake, and in sedimentation rates. Both proxies document drastic changes in vegetation composition in the early Holocene with an increased number of trees and shrubs and the appearance of new tree taxa in the lake's vicinity. The sedaDNA method suggests that the Late Pleistocene steppe-tundra vegetation supported a higher number of terrestrial plant taxa than the forested Holocene. This could be explained, for example, by the "keystone herbivore" hypothesis, which suggests that Late Pleistocene megaherbivores were able to maintain a high plant diversity. This is discussed in the light of the data with the broadly accepted species-area hypothesis as steppe-tundra covered such an extensive area during the Late Pleistocene.
Selenium (Se) is known to contribute to several vital physiological functions in mammals: antioxidant defense, fertility, thyroid hormone metabolism, and immune response. Growing evidence indicates the crucial role of Se and Se-containing selenoproteins in the brain and brain function. As for the other essential trace elements, dietary Se needs to reach effective concentrations in the central nervous system (CNS) to exert its functions. To do so, Se-species have to cross the blood-brain barrier (BBB) and/or blood-cerebrospinal fluid barrier (BCB) of the choroid plexus. The main interface between the general circulation of the body and the CNS is the BBB. Endothelial cells of brain capillaries forming the so-called tight junctions are the primary anatomic units of the BBB, mainly responsible for barrier function. The current review focuses on Se transport to the brain, primarily including selenoprotein P/low-density lipoprotein receptor-related protein 8 (LRP8, also known as apolipoprotein E receptor-2) dependent pathway, and supplementary transport routes of Se into the brain via low molecular weight Se-species. Additionally, the potential role of Se and selenoproteins in the BBB, BCB, and neurovascular unit (NVU) is discussed. Finally, the perspectives regarding investigating the role of Se and selenoproteins in the gut-brain axis are outlined.