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Co‐Doping Approach for Enhanced Electron Extraction to TiO2 for Stable Inorganic Perovskite Solar Cells
No full textInorganic perovskite CsPbI3 solar cells hold great potential for improving the operational stability of perovskite photovoltaics. However, electron extraction is limited by the low conductivity of TiO2, representing a bottleneck for achieving stable performance. In this study, a co‐doping strategy for TiO2 using Nb(V) and Sn(IV), which reduces the material's work function by 80 meV compared to Nb(V) mono‐doped TiO2, is introduced. To gain fundamental understanding of the processes at the interfaces between the perovskite and charge‐selective layer, transient surface photovoltage measurements are applied, revealing the beneficial effect of the energetic and structural modification on electron extraction across the CsPbI3/TiO2 interface. Using 2D drift‐diffusion simulations, it is found that co‐doping reduces the interface hole recombination velocity by two orders of magnitude, increasing the concentration of extracted electrons by 20%. When integrated into n–i–p solar cells, co‐doped TiO2 enhances the projected TS80 lifetimes under continuous AM1.5G illumination by a factor of 25 compared to mono‐doped TiO2. This study provides fundamental insights into interfacial charge extraction and its correlation with operational stability of perovskite solar cells, offering potential applications for other charge‐selective contacts.HORIZON EUROPEDeutsche Forschungsgemeinschaft 10.13039/501100001659Programme d’Investissement d’AvenirBundesministerium für Bildung und Forschung 10.13039/501100002347Bundesministerium für Wirtschaft und KlimaschutzPeer Reviewe
Voices Around the South Tyrolean Herbal Pharmacy—Exploring the Stakeholder Landscape and Perspectives on Medicinal Plants as Culturally Salient Species
No full textTraditional medicine, including the use of medicinal plants, is integral to healthcare and empowerment of individuals and communities worldwide. Preserving traditional knowledge of medicinal plants requires an understanding of social dynamics and knowledge transfer mechanisms that sustain these practices. This study aimed to explore stakeholder perspectives on the use of medicinal plants in South Tyrol (Italy) through a mixed-methods approach, combining an online survey with semi-structured interviews. We found that the use of medicinal plants is deeply rooted in local communities, supported by factors such as their local accessibility, their presence in education and medical self-care, and a strong local belief in plants’ healing powers. Knowledge is primarily transferred through women underscoring the gendered nature of this cultural heritage. However, sustainable and commercial use of medicinal plants is challenged by a complex set of socio-political barriers, including limited political prioritization and perceived disengagement of local authorities. Our findings highlight the need for coordinated multi-stakeholder strategies, including the establishment of a dedicated chamber to set production standards, safeguard commercial use, advocate for medicinal plant use, mediate conflicts, and address barriers collaboratively, ensuring the integration of traditional practices into modern contexts.Peer Reviewe
Compositional Engineering of Ti3C2TxMXene-NiMoO4 Hybrid Nanostructures for Enhanced Electrocatalytic Water Oxidation
No full textA critical step in realizing the vision of green hydrogen through water splitting is to design oxygen evolution reaction (OER) catalysts that showcase a good balance of activity and stability. This work reports the compositional tuning of a NiMoO4 material and then the subsequent varying of Ti3C2Tx MXene with the NiMoO4 hybrid nanostructures as OER catalysts in alkaline media. In this work, the optimum NiMoO4 hybrid catalyst retained good stability over 24 h of chronopotentiometry on industrial relevant supports (Ni Felt) with an overpotential value of ca. 339 mV at 100 mA cm–2. Operando Raman spectroscopy revealed that catalytically active β-NiOOH species are formed during OER in NiMoO4 at lower overpotentials than for pure NiO and that a higher amount of the β-NiOOH was found in the 5% MXene loading. The ICP-OES analysis showed that Mo dissolution follows a volcano trend with MXene loading (peaking at 5 wt %) before decreasing at 10 wt %. Overall, these results hold great promises for rational design strategies for MXene-supported water oxidation catalysts in alkaline electrolytes.Horizon 2020 Framework Programme 10.13039/100010661European Research Council 10.13039/501100000781Science Foundation Ireland 10.13039/501100001602Science Foundation Ireland 10.13039/501100001602Science Foundation Ireland 10.13039/501100001602Deutscher Akademischer Austauschdienst 10.13039/501100001655Deutsche Forschungsgemeinschaft 10.13039/501100001659Bundesministerium f?r Bildung und Forschung 10.13039/501100002347Helmholtz Association 10.13039/501100009318Peer Reviewe
Mechanical Comparison of Escherichia coli Biofilms with Altered Matrix Composition: A Study Combining Shear-Rheology and Microindentation
No full textThe mechanical properties of bacterial biofilms depend on the composition and microstructure of their extracellular matrix (ECM), which constitutes a network of extracellular proteins and polysaccharide fibers. In particular, Escherichia coli macrocolony biofilms were suggested to present tissue-like elasticity due to a dense fiber network consisting of amyloid curli and phosphoethanolamine-modified cellulose (pEtN-cellulose). To understand the contribution of these two main ECM components to the emergent mechanical properties of E. coli biofilms, we performed shear-rheology and microindentation experiments on biofilms grown from E. coli strains that produce different ECM. We measured that biofilms containing curli fibers are stiffer in compression than curli-deficient biofilms. We further quantitatively demonstrate the crucial contribution of pEtN-cellulose, and especially of the pEtN modification, to the stiffness and structural stability of biofilms when associated with curli fibers. To compare the differences observed between the two methods, we also investigated how the structure and mechanical properties of biofilms with different ECM compositions are affected by the sample preparation method used for shear-rheology. We found that biofilm homogenization, used prior to shear-rheology, destroys the macroscale structure of the biofilm while the microscopic ECM architecture may remain intact. The resulting changes in biofilm mechanical properties highlight the respective advantages and limitations of the two complementary mechanical characterization techniques in the context of biofilm research. As such, our work does not only describe the role of the ECM on the mechanical properties of E. coli biofilms. It also informs the biofilm community on considering sample preparation when interpreting mechanical data of biofilm-based materials.Deutsche Forschungsgemeinschaft 10.13039/501100001659Max-Planck-Gesellschaft 10.13039/501100004189Max Planck Queensland Centre for the Materials Science of Extracellular Matrices NAPeer Reviewe
Mediävistische Perspektiven
No full textThe publication of this work was supported by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Verzicht ist ein Wort der Stunde – ein Reizwort. Denn weniger zu tun als üblich oder nicht mehr zu handeln, wie es erwartet wird, irritiert. Dieser Gedanke wird hier für das Mittelalter fruchtbar gemacht. Der interdisziplinäre Band schlägt in diesem Sinne vor, Verzicht handlungstheoretisch zu verstehen. So wird er auf vielfältige Phänomene übertragbar. Erstmals für das Mittelalter versammelt der Sammelband Beiträge zum Verzicht auf ganz verschiedene Dinge: auf Ämter, auf Rache, auf Komfort, auf Darstellungskonventionen. Die Beiträger:innen verstehen Verzicht als Unterbrechung von Erwartbarem. Dabei wird deutlich, dass Verzicht riskant ist, denn er unterläuft Routinen. Verzicht ist aber auch eine Form des Tauschs, denn er verspricht einen Mehrwert. Und Verzicht ist weder ganz freiwillig noch völlig unfreiwillig und lädt so ein, Handeln zwischen Gewohnheit, Änderungsdruck und Eigensinn zu untersuchen. Die einzelnen Beiträge untersuchen Verzichtsphänomene in verschiedenen Zeiten und Räumen – vom Frühmittelalter bis in die Renaissance, von Island bis Byzanz. Sie fragen nach Logiken, Semantiken und Szenarien des Verzichtens. Deutlich wird: Verzicht ist im Mittelalter nicht allein ein Phänomen von Askese, Mönchtum und Frömmigkeit. Vielmehr ist er ein Handlungstyp, der auch innerweltlich relevant ist und Fragen nach sozialen Konventionen aufwirft. In der fächerübergreifenden Zusammenschau werden Situationen des Weniger- und Nicht-mehr-Tuns vergleichbar. So erschließt der Band neue Perspektiven auf Routinen, Risiken und Handlungsspielräume in mittelalterlichen Gesellschaften
Comparing the Level of Punitiveness in the U.S. and Germany
No full textThe article discusses the factors that explain the substantial differences in imprisonment rates between Germany and the U.S.; starting point is Michael Tonry’s thesis that these differences ‘mostly reflect deliberate policy choices’. The author points out that explanations must be more varied and that structural features of criminal justice systems are of great importance. Another argument made is that not every development deserves praise simply because it has the side effect of moderating imprisonment rates (such as bureaucratic and thus inefficient prosecution).Open Access funding enabled and organized by Projekt DEAL.Max Planck Institute for the Study of Crime, Security and Law (2)Peer Reviewe
Incorporating ecological mechanisms for better predictions in freshwater ecosystems under stress
No full textSüßwasserökosysteme sind zunehmend durch anthropogene Stressfaktoren geschädigt, was zu einem Rückgang der Biodiversität, zur Beeinträchtigung von Ökosystemfunktionen und zur Gefährdung ihrer Stabilität führt. Trotz eingeleiteter Schutz- und Wiederherstellungsmaßnahmen verlaufen Erholungsprozesse oft unvollständig oder unerwartet. Daher sind präzisere Vorhersageansätze nötig, um diese Prozesse besser zu verstehen und effektiver zu steuern. Aktuelle Modelle, etwa Artenverteilungsmodelle, vernachlässigen jedoch häufig zentrale ökologische Mechanismen wie biotische Interaktionen, Ausbreitung, Toleranzen, Konnektivität und Nischendynamik, die das Vorkommen von Arten beeinflussen. Diese Arbeit untersucht anhand von Makroinvertebraten die Rolle solcher Mechanismen in Degradations- und Erholungsprozessen und deren Bedeutung für verbesserte Modellierungen. Methodisch wurden systematische Übersichten, Meta-Analysen, Verteilungsmodelle und Nischengrößenschätzungen eingesetzt, um eine ganzheitliche Perspektive zu gewinnen. Die Ergebnisse zeigen, dass biotische Interaktionen bei der Erklärung von Verteilungsmustern und Stressorwirkungen oft unzureichend berücksichtigt werden, was durch begrenzte Datenintegration und Wissenslücken bedingt ist. Ebenso beeinflusst die Berücksichtigung von Ausbreitung die Prognosekraft von Modellen deutlich, besonders bei Arten mit unterschiedlichen Toleranzen. Die Dynamik ökologischer Nischen, beeinflusst durch Datenlage und Mechanismen, variiert stark zwischen Arten und kann Modellannahmen wie Nischenkonservatismus infrage stellen. Insgesamt betont die Arbeit die Notwendigkeit, ökologische Mechanismen und Nischendynamik in Vorhersagemodelle zu integrieren, um genauere Prognosen und effektivere Wiederherstellungsstrategien für gefährdete Süßwasserökosysteme zu ermöglichen.Freshwater ecosystems are increasingly degraded by multiple stressors driven by anthropogenic pressures. These stressors have caused major biodiversity losses and impaired ecosystem functions, threatening ecosystem stability. While conservation and restoration efforts aim to mitigate these impacts and support recovery, such interventions often result in incomplete or divergent recovery pathways. Accurate predictive tools are therefore essential to better understand degradation and recovery processes and improve management strategies. However, current models, such as species distribution models, often overlook key ecological mechanisms like biotic interactions, dispersal, species tolerances, connectivity, and niche size—all of which jointly shape species responses to environmental change. This thesis explores these mechanisms using macroinvertebrates as model organisms and examines their implications for improving predictive modelling. A combination of methods—systematic reviews, meta-analyses, species distribution models, and niche size estimates—was used to provide an integrated perspective. Results show that current models often neglect the role of biotic interactions due to limited data integration and knowledge gaps. Yet, these interactions strongly influence how stressors affect ecosystems and determine degradation outcomes. Incorporating dispersal significantly altered model predictions, especially for species with varying tolerance levels, highlighting the need to consider species-specific responses. Additionally, environmental niche sizes were found to be dynamic, influenced by data structure and ecological mechanisms, with implications for model accuracy and transferability. These findings underscore the importance of integrating ecological mechanisms and niche dynamics into predictive frameworks to improve recovery forecasts and inform more effective restoration strategies for freshwater ecosystems under growing anthropogenic pressure
Tuning Reactivity in Cu/TEMPO Catalyzed Alcohol Oxidation Reactions
No full textA dinuclear copper(I) complex Cu2L22 (L2 = 3,3‐dimethyl‐1‐(1‐methyl‐1H‐benzo[d]imidazole‐2‐yl)‐N‐(propan‐2‐ylidene)butan‐2‐amine) containing benzimidazole and imino donors was previously reported by some of us as an efficient catalyst for the aerobic oxidation of alcohols to aldehydes in presence of TEMPO (2,2,6,6‐tetramethylpiperidinyloxyl) and an external base NMI (N‐methyl imidazole). Cu(III)2(bis‐μ‐oxo) and Cu(II)2(bis‐μ‐hydroxo) cores were trapped as viable intermediates in the reaction, which provided deeper mechanistic insights. Here, we report two new ligand systems L3 (N‐isopropyl‐3,3‐dimethyl‐1‐(1‐methyl‐1H‐benzol[d]imidazole‐2‐yl)butane‐2‐amine) and L4 ((Z)‐2,4‐di‐tert‐butyl‐6‐(((3,3‐dimethyl‐1‐(1‐methyl‐1H‐benzol[d]imidazole‐2‐yl)butane‐2‐yl)imino)methyl)phenol), which are designed to perturb the overall electronics of the complexes and the resulting effects on their O2 activation mechanisms. The stronger donation of the secondary amine group stabilizes a mononuclear CuIL3 core, which nevertheless follows a dinuclear O2 activation mechanism as in Cu2L22. Notably, the CuIL3/TEMPO catalyst system performs the aerobic oxidation of alcohols to aldehydes with good yields and turnover numbers, even in the absence of NMI. The dinuclear CuI2L42 complex involving a non‐innocent phenolate group, in contrast, exhibits depleted catalytic activity, because of the instability of the Cu(III)2(bis‐μ‐oxo) core against intramolecular H‐atom abstraction to form an alkoxo bridged dicopper(II) complex.Deutsche Forschungsgemeinschaft 10.13039/501100001659Peer Reviewe
10. Symposium des Jungen Strafrechts. Berlin 2024
No full textThe publication of this work was supported by the Open Access Publication Fund of Humboldt-Universität zu Berlin.Friedenskrise, Corona-Krise, Klimakrise, die so bezeichnete „Migrationskrise“. Die letzten Jahrzehnte waren und sind von Krisenerfahrungen geprägt. Diese Krisen haben auch im Strafrecht (neue) Rechtsprobleme geschaffen und grundsätzliche Fragen (neu) aufgeworfen. Der vorliegende Tagungsband des 10. Symposiums des Jungen Strafrechts greift diese Fragen auf. Vier Themenbereiche werden dabei vertieft: Grundfragen des Verhältnisses von Strafrecht und Krise, Klima- und Nahrungsmittelkrise sowie die damit verbundenen Protestformen, die Rolle des Strafrechts in der Pandemie und im Verhältnis zur so bezeichneten Migrationskrise sowie Krise und Strafrechtskritik
Marginal gender agreement in Momuna
No full textMomuna, an understudied language of Western New Guinea whose affiliation is a matter of dispute, exhibits a sort of extremely marginal gender agreement that is of interest both typologically and diachronically. While adjectives are generally uninflected, the expression for ‘old (animate)’ distinguishes masculine and feminine forms. Internal evidence as well as comparison with Mek languages (traditionally considered to be a branch of the Trans New Guinea family and spoken to the north of Momuna) both and independently suggest that the Momuna forms for ‘old (animate)’ might have decategorized from complex nouns with a shared stem that originally was a term for older kinship. Typologically, marginal gender agreement in Momuna is well in line with the trend that gender, if not cumulating with another grammatical category, is not obligatory and not marked on multiple agreement targets