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Abstract Males in many species possess sexually selected weapons that they use to fight for mating opportunities. It is well established that male-male competition can lead to physical injuries for males. However, very few studies have looked at the physical consequences for conspecific females. We hypothesized that living with males in a species with male-male competition would result in female injury. Because larger female invertebrates typically have greater reproductive output, they have higher resource value for males and can elicit aggression and fighting. Thus, we further hypothesized that larger females in this context would receive more injuries. For this study, we focused on the leaf-footed cactus bug, Narnia femorata (Hemiptera: Coreidae), a species of insect in which males fight using their spiny and enlarged hindlegs. In just 2 h of observation, we documented males competing with other males in 61% of 103 trials. In 43% of these 63 competitions, females were physically contacted and sometimes attacked with a kick or squeeze. We left insects in social groups for 74 h and found that females living with multiple males had a higher likelihood of obtaining injuries (26.2% of 103 trials) compared to those living only with females (9.7% of 103 trials). In addition, larger females were more likely to be injured compared to smaller females. Our study highlights the harm that females can experience in species with male-male competition. 

Small electrodes capable of detecting Mn dissolution and oxygen evolution are placed near operating Mn-based lithium-ion battery cathodes to track their degradation, informing on mechanism and revealing how additives might help decrease degradation. 

  Widespread concern about the “decline of taxonomy” has motivated calls to action to re-invigorate the field by enhancing taxonomic training, along with increasing taxonomy funding and positions, improving citation rates, and describing species more rapidly. Taxonomic training has historically been apprentice style, with individuals training for years under expert guidance. This approach offers a rich learning experience but inherently limits trainee number and relies on students’ earlier exposure to taxonomy. We describe a scaled-up taxonomic training model using a Course-based Undergraduate Research Experience (CURE) to provide early taxonomy research experience and broadly applicable scientific research skills. Results from a 45-student taxonomy-focused course conducted concurrently at 2 universities resulted in increased interest in taxonomic revisions and ability to explain taxonomic concepts, with one-third of students developing more interest in taxonomic careers. General science skill development was high when compared to a large sample of other CURE courses. The research focus of the course was taxonomic revision of the ant genus Nylanderia in Meso-America; students worked with instructors to delimit and describe new species. Here, we present 4 newly described species: Nylanderia ambulator, sp. nov. Nylanderia aurantia, sp. nov., Nylanderia collaborans, sp. nov., and Nylanderia maximon, sp. nov., with an additional 13 putative species noted for further revisionary work. This expanded taxonomic training model combines hands-on research experience with peer-learning and caters to students with minimal exposure to taxonomy. As a result, this approach broadens recruitment to more diverse audiences and results in enhanced awareness of and appreciation for taxonomy. 

Abstract Cu is the most promising metal catalyst for CO₂electroreduction (CO₂RR) to multi-carbon products, yet the structure sensitivity of the reaction and the stability versus restructuring of the catalyst surface under reaction conditions remain controversial. Here, atomic scale simulations of surface energies and reaction pathway kinetics supported by experimental evidence unveil that CO₂RR does not take place on perfect planar Cu(111) and Cu(100) surfaces but rather on steps or kinks. These planar surfaces tend to restructure in reaction conditions to the active stepped surfaces, with the strong binding of CO on defective sites acting as a thermodynamic driving force. Notably, we identify that the square motifs adjacent to defects, not the defects themselves, as the active sites for CO₂RR via synergistic effect. We evaluate these mechanisms against experiments of CO₂RR on ultra-high vacuum-prepared ultraclean Cu surfaces, uncovering the crucial role of step-edge orientation in steering selectivity. Overall, our study refines the structural sensitivity of CO₂RR on Cu at the atomic level, highlights the self-activation mechanism and elucidates the origin of in situ restructuring of Cu surfaces during the reaction. 

Abstract Three BINOL‐based unsymmetric chiral dialdehydes, (S)‐4, (S)‐5, and (S)‐6, each containing a salicylaldehyde moiety and anortho‐,meta‐ orpara‐substituted benzaldehyde unit, are synthesized and used to react with the enantiomers of an unsymmetric chiral diamine, lysine. These reactions represent the first examples of regioselective as well as enantioselective reactions of an unsymmetric chiral dialdehyde with an unsymmetric chiral diamine to generate unsymmetric chiral macrocycles. The addition of Zn²⁺can further enhance the selectivity for the macrocycle formation. Compounds (S)‐4and (S)‐5are found to exhibit chemoselective and enantioselective fluorescent recognition of lysine in the presence of Zn²⁺. 

Category selectivity is a fundamental principle of organization of perceptual brain regions. Human occipitotemporal cortex is subdivided into areas that respond preferentially to faces, bodies, artifacts, and scenes. However, observers need to combine information about objects from different categories to form a coherent understanding of the world. How is this multicategory information encoded in the brain? Studying the multivariate interactions between brain regions of male and female human subjects with fMRI and artificial neural networks, we found that the angular gyrus shows joint statistical dependence with multiple category-selective regions. Adjacent regions show effects for the combination of scenes and each other category, suggesting that scenes provide a context to combine information about the world. Additional analyses revealed a cortical map of areas that encode information across different subsets of categories, indicating that multicategory information is not encoded in a single centralized location, but in multiple distinct brain regions. SIGNIFICANCE STATEMENTMany cognitive tasks require combining information about entities from different categories. However, visual information about different categorical objects is processed by separate, specialized brain regions. How is the joint representation from multiple category-selective regions implemented in the brain? Using fMRI movie data and state-of-the-art multivariate statistical dependence based on artificial neural networks, we identified the angular gyrus encoding responses across face-, body-, artifact-, and scene-selective regions. Further, we showed a cortical map of areas that encode information across different subsets of categories. These findings suggest that multicategory information is not encoded in a single centralized location, but at multiple cortical sites which might contribute to distinct cognitive functions, offering insights to understand integration in a variety of domains.