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Among biocollections, mollusks are a particularly powerful resource for a wide range of studies, including biogeography, conservation, ecology, environmental monitoring, evolutionary biology, and systematics. U.S. mollusk collections are housed in stand-alone natural history museums, at universities, and in a variety of governmental and non-governmental institutions. Differing in their histories, specializations, and uses, they share common needs for long-term development, and collectively contribute to biodiversity knowledge at regional, national, and global scales. Commitment by dedicated staff, collectors, and volunteers, institutional investments, philanthropy, and governmental funding have built and maintained these collections and their support infrastructure. Efforts by the North American malacological collection community since the early 1970s led to coordination in database design but left the data isolated in individual institutions. Collection digitization developed through a combination of individual/institutional initiatives and federally supported projects funded by the National Science Foundation (NSF) and the Institute of Museum and Library Services (IMLS). Advances in digital technology enabled the shift toward nationally and globally unified collections. Networking and collaboration were greatly accelerated by NSF’s Advancing Digitization of Biodiversity Collections (ADBC) program, which created a central coordinating organization (iDigBio) and funded Thematic Collections Network (TCN) projects. One such TCN was developed to mobilize nearly 90% of the known U.S. museum-collections-based data of the U.S. Atlantic and Gulf coasts (Mobilizing Millions of Marine Mollusks of the Eastern Seaboard—ESB). The project, involving 16 museum collections (plus the Smithsonian Institution as federal partner), combines data from approximately 4.5 million specimens collected from the ESB region and makes them available to the TCN portal InvertEBase and other aggregators such as iDigBio and GBIF. In addition to fostering community and expanding the corpus of available digitized mollusk records through new data entry and georeferencing (GEOLocate, CoGe) and standardizing taxonomy, the project drove key innovations for the invertebrate collections community. For instance, it worked with the Biodiversity Information Standards (TDWG) group to create a new Darwin Core standard term, “Vitality”, expanded GEOLocate to support complex geospatial types, integrated global elevation and bathymetric datasets directly into georeferencing workflow, and developed various education and outreach public outreach products. Synthesizing from the 15 following articles with individual histories of ESB-participating mollusk collections, several topics are discussed—such as what defines a “good” mollusk collection in the digital age and the importance of federal support for this national resource. 

Future climate change may bring local benefits or penalties to surface air pollution, resulting from changing temperature, precipitation, and transport patterns, as well as changes in climate-sensitive natural precursor emissions. Here, we estimate the climate penalties and benefits at the end of this century with regard to surface ozone and fine particulate matter (PM ${}_{2.5}$; excluding dust and smoke) using a one-way offline coupling between a general circulation model and a global 3-D chemical-transport model. We archive meteorology for the present day (2005 to 2014) and end of this century (2090 to 2099) for seven future scenarios developed for Phase 6 of the Coupled Model Intercomparison Project. The model isolates the impact of forecasted anthropogenic precursor emission changes versus that of climate-only driven changes on surface ozone and PM ${}_{2.5}$for scenarios ranging from extreme mitigation to extreme warming. We then relate these changes to impacts on human mortality and crop production. We find ozone penalties over nearly all land areas with increasing warming. We find net benefits due to climate-driven changes in PM ${}_{2.5}$in the Northern Extratropics, but net penalties in the Tropics and Southern Hemisphere, where most population growth is forecast for the coming century. 

Two series of lactone-terminated alkanethiol adsorbates with five- and six-membered lactone groups, γ-COCnSH and δ-COCnSH (n = 11, 12), were synthesized and employed to create nanoscale self-assembled monolayers (SAMs) on gold substrates to mimic the properties of commercially available poly(lactic-co-glycolic acid) (PLGA) and poly(glycolic acid) (PGA) surfaces. 1H and 13C nuclear magnetic resonance (NMR) were employed to characterize the adsorbate molecules. The thicknesses of the corresponding self-assembled monolayers (SAMs) were evaluated by ellipsometry. The conformational characteristics of the SAMs were analyzed using polarization modulation infrared reflection adsorption spectroscopy (PM-IRRAS), with a focus on the C-H antisymmetric stretching vibrations of the alkyl spacers. To evaluate the packing densities of the monolayers, X-ray photoelectron spectroscopy (XPS) measurements were performed. Separately, contact angle measurements provided insights into the wettability of the surfaces. Remarkably, the contact angle data across a broad range of probe liquids for the γ-COC11SH and γ-COC12SH SAMs were consistently similar to each other and to the contact angle values of the PLGA surface, rather than to PGA. This finding suggests that the lactone-terminated SAMs investigated in this study effectively mimic nanoscale polyester surfaces, enabling the exploration of interfacial properties of polyesters in the absence of swelling and/or surface reconstruction phenomena. 

Abstract Iron oxide nanoparticles (IONPs) are widely used for biomedical applications due to their unique magnetic properties and biocompatibility. However, the controlled synthesis of IONPs with tunable particle sizes and crystallite/grain sizes to achieve desired magnetic functionalities across single‐domain and multi‐domain size ranges remains an important challenge. Here, a facile synthetic method is used to produce iron oxide nanospheres (IONSs) with controllable size and crystallinity for magnetic tunability. First, highly crystalline Fe₃O₄IONSs (crystallite sizes above 24 nm) having an average diameter of 50 to 400 nm are synthesized with enhanced ferrimagnetic properties. The magnetic properties of these highly crystalline IONSs are comparable to those of their nanocube counterparts, which typically possess superior magnetic properties. Second, the crystallite size can be widely tuned from 37 to 10 nm while maintaining the overall particle diameter, thereby allowing precise manipulation from the ferrimagnetic to the superparamagnetic state. In addition, demonstrations of reaction scale‐up and the proposed growth mechanism of the IONSs are presented. This study highlights the pivotal role of crystal size in controlling the magnetic properties of IONSs and offers a viable means to produce IONSs with magnetic properties desirable for wider applications in sensors, electronics, energy, environmental remediation, and biomedicine. 

Food sharing is a costly form of cooperation that was likely critical to human evolutionary success, including the emergence of human's life history strategy. Food sharing in human communities may be maintained through a number of pathways, including direct dyadic reciprocity, reputation‐based processes, and kin‐biased exchange. Differences in reproductive demands, labor, and cultural norms may also result in gendered differences in cooperative networks. Here, we examine cooperative networks in egalitarian BaYaka foragers from the Congo Basin. We collected social network data from 112 adults in 41 households in this subsistence community. We implement a Bayesian latent network model to assess individual‐, dyadic‐, and block‐level predictors of food sharing partners. Conditioning on covariates, we found limited evidence for direct dyadic reciprocity in food sharing. Despite local norms regarding prestige avoidance, we found status‐based homophily. High‐status individuals—council members and local healers—were more likely to share with one another. Importantly, our results highlight gender differences in patterns of food sharing, interacting with genetic relatedness. Women were more likely to share with one another, especially with kin as genetic relatedness increased. Our results align with evolutionary framing emphasizing kin selection in costly cooperation. The results showing that women cooperate with other women, particularly kin, also complement sex‐based patterns in some other mammalian species, potentially reflecting the social support necessary to manage reproductive costs and childcare. BaYaka women's subsistence productivity and local cultural dynamics for autonomy and egalitarianism may likewise help facilitate women's preferential cooperation with one another. 

Molecular interactions at interfaces have a significant effect on the wetting properties of surfaces on a macroscale.