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Abstract Persulfides (RSS^–) and thioselenides (RSSe^–) play important roles in biological S and Se transfer reactions, and their interactions with Lewis acidic moieties exert control over reactivity. Here, we report the synthesis and reactivity of mononuclear Zn²⁺persulfide and thioselenide complexes from a unified synthetic strategy of using isolable dichalcogenide precursors. Highlighting the benefits of replacing S with Se, we use⁷⁷Se NMR spectroscopy to reveal the effects of Lewis acid coordination (K⁺, Na⁺, Zn²⁺) on the electronic environment of the terminal Se of the thioselenide (R–S_β–Se_α^–). Coordination of RSSe^–to Zn²⁺polarizes the Se─S bond, rendering the internal sulfur atom (R–S_β–Se_α^–) susceptible to nucleophilic attack and resulting in selenide (Se^2–) release. We also prepared a mononuclear Zn²⁺persulfide complex and probed differences in persulfide nucleophilicity when compared to the parent thiolate. Alkylation of the Zn²⁺persulfide is considerably faster than the Zn²⁺thiolate, supporting the proposed nucleophilicity enhancement of persulfides due to the α‐effect, and providing new insights into persulfide reactivity when coordinated to metals. Taken together, these investigations highlight the utility of small molecule synthetic models in advancing insights into the biological chemistry of metal dichaclogenides. 

Hydrogen selenide (H2Se) is an emerging bioregulator and precursor to essential selenium-containing biomolecules. We show that aryl isoselenocyanates (ISeC-R) release H2Se upon activation by cysteine, and that electronic substitution can modulate release profiles. We also demonstrate applications to live cell imaging, expanding available tools for investigating H2Se chemical biology. 

Abstract Gelatinous zooplankton serve diverse ecological roles in shelf food webs—from grazers to predators. However, their spatial niches are poorly resolved, especially at detailed taxonomic levels, due to conventional techniques that are unable to measure distributions at fine spatial scales. Seasonal in situ imaging transects across the dynamic northern Gulf of Mexico demonstrated that taxonomic diversity of gelatinous zooplankton increases with stratification and habitat heterogeneity. Taxa displayed low spatial niche overlap (~ 10%, Schoener'sD), independent of season (stratified, river‐influenced, and well mixed), and even when associated with similar water mass properties. This suggests that oceanography structures the distributions of gelatinous organisms and water mass preferences, but ecological interactions among taxa generate distinct taxon‐specific spatial niches. Although automated image classification algorithms currently prioritize broad taxonomic groups, detailed identifications and improved resolution of interactions (predator–prey, competition, etc.) may underlie a predictive framework for gelatinous abundances and diversity. 

Abstract Specific ions can be intercalated into functional materials using the electrolyte gating technique, which has been widely used to regulate channel conductance in transistors and develop low‐power neuromorphic devices. However, in these devices, fundamental exploration of ion intercalation‐induced structural phase transitions remains largely overlooked and rarely explored. Here, the lithium‐based electrolyte gating technique is used to probe the collective interactions between ions, lattices, and electrons in a van der Waals ferroelectric semiconductor α‐In₂Se₃. Using a polymer electrolyte as the lithium‐ion reservoir and α‐In₂Se₃as the channel material, the intercalated lithium concentration via a gate electric field is modulated. This manipulation drives a phase transition in α‐In₂Se₃from a ferroelectric semiconductor to a dirty metal and finally to a metal, accompanied by a structural transformation. Concurrently, with enhanced intercalation, the ferroelectric hysteresis window progressively narrows and eventually disappears, indicating the evolution from switchable to non‐switchable polarization. This study represents a promising platform for the artificial construction of correlated material systems, enabling a systematic investigation into the interaction of ferroelectricity and electronic conduction using ion intercalation. 

Abstract In Earth history, our understanding of how large‐bodied herbivores shape a variety of ecosystem processes is limited by the quality of paleoecological proxies for herbivore composition and abundance. Fecal stanols are lipids that can be produced by microbes within animal digestive systems and that could remedy this dearth of proxies. We used two multi‐decadal herbivore exclosures in Kruger National Park, South Africa, to constrain whether and how biomarker signatures preserve signals of herbivore abundance. Soil samples and dung counts were collected along transects across crests, mid‐slopes, and sodic sites inside and outside exclosures. Soils were analyzed for steroid (sterols and stanols) concentrations and distributions. We found that stanol concentrations were significantly greater in sodic soils outside exclosures, where herbivore dung densities were greatest. In contrast, sterol concentrations did not differ between treatments. Ratios of stanol isomers to sterols, which account for both compound degradation and source, increased strongly with herbivore dung counts. Finally, while herbivore species compositions influenced steroid distributions, total herbivore abundance was their strongest predictor. Further calibration is needed, but this work provides strong preliminary evidence that wild herbivore populations are quantitatively recorded by fecal biomarker distributions. 

Data associated with Figures, Tables, and population parameter samples associated with  The population of merging compact binaries inferred using gravitational waves through GWTC-3 , </strong> LIGO DCC, arXiv, PRX. </strong> This is v2, superseding v1. Please see the README.md for more information.</p> LIGO Laboratory and Advanced LIGO are funded by the United States National Science Foundation (NSF) as well as the Science and Technology Facilities Council (STFC) of the United Kingdom, the Max-Planck-Society (MPS), and the State of Niedersachsen/Germany for support of the construction of Advanced LIGO and construction and operation of the GEO600 detector. Additional support for Advanced LIGO was provided by the Australian Research Council. Virgo is funded, through the European Gravitational Observatory (EGO), by the French Centre National de Recherche Scientifique (CNRS), the Italian Istituto Nazionale di Fisica Nucleare (INFN) and the Dutch Nikhef, with contributions by institutions from Belgium, Germany, Greece, Hungary, Ireland, Japan, Monaco, Poland, Portugal, Spain. The construction and operation of KAGRA are funded by Ministry of Education, Culture, Sports, Science and Technology (MEXT), and Japan Society for the Promotion of Science (JSPS), National Research Foundation (NRF) and Ministry of Science and ICT (MSIT) in Korea, Academia Sinica (AS) and the Ministry of Science and Technology (MoST) in Taiwan.