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The field of geology is poised to make a fundamental transition in the quality, character, and types of science that are possible for practitioners. Geologists are developing data systems—consistent with their workflow—to digitally collect, store, and share data. Separately, geologists and cognitive scientists have been working together to develop tools that can characterize the level of uncertainty of both data and models. The transformational change comes from the simultaneous combination of these two approaches: digital data systems designed to capture and convey scientific uncertainty. This approach promotes better data collection practice, improves reproducibility, and increases trust in community-based digital data. We applied these methods—attending to uncertainty and its incorporation into digital repositories—to the Sage Hen Flat pluton in eastern California, USA, where two published maps provide different interpretations. Incorporating uncertainty into our workflow, from field data collection to publication, allows us to move beyond binary choices (e.g., is this data/model right or wrong?) to a more nuanced view (e.g., what is my level of uncertainty about the data/model?) that is shareable with the larger community. 

Recent summer surveys of the northeastern Chukchi Sea found pelagic fishes were dominated by large numbers of age-0 Arctic cod (Boreogadus saida, Gadidae) and walleye pollock (Gadus chalcogrammus, Gadidae), while adult fishes were comparatively scarce. The source and fate of these young fishes remain unclear, as sampling in this region is impeded by seasonal ice cover much of the year. Seafloor-mounted echosounders were deployed at three locations in the northeastern Chukchi Sea from 2017 to 2019 to determine the movement and seasonal variability of these age-0 gadids. These observations indicated that the abundance of pelagic fishes and community composition on the Chukchi Sea shelf were highly variable on seasonal time scales, with few fish present in winter. Tracking indicated that fish movements were strongly correlated with local currents. Fishes were primarily displaced to the northeast in summer and fall, with periodic reversals towards the southwest driven by changes in regional wind patterns. The flux of fishes past the moorings indicated that the prevailing northward currents transport a large proportion of the age-0 pelagic fishes present on the Chukchi shelf in summer to the northeast by fall, leading to relatively low abundances of age-1+fishes in this environment.

 

The Maine Department of Marine Resources (MEDMR) is a state agency tasked with developing, conserving, researching, and promoting commercial and recreational marine fisheries across Maine’s vast coastline. Close collaborations with industry members in each of the 30 or more fisheries that support Maine’s coastal economy are central to MEDMR’s efforts to address this suite of tasks. Here we reflect on recent decades of MEDMR's work and demonstrate how MEDMR fisheries research programmes are preparing for an uncertain future through the lens of three broadly applicable climate-driven challenges: (1) a rapidly changing marine ecosystem; (2) recommendations driven by state and federal climate initiatives; and (3) the need to share institutional knowledge with a new generation of marine resource scientists. We do this by highlighting our scientific and co-management approach to coastal Maine fisheries that have prospered, declined, or followed a unique trend over the last 25+ years. We use these examples to illustrate our lessons learned when studying a diverse array of fisheries, highlight the importance of collaborations with academia and the commercial fishing industry, and share our recommendations to marine resource scientists for addressing the climate-driven challenges that motivated this work.

 

Targeted delivery of nucleic acid therapeutics to the lungs could transform treatment options for pulmonary disease. We have previously developed oligomeric charge-altering releasable transporters (CARTs) for in vivo mRNA transfection and demonstrated their efficacy for use in mRNA-based cancer vaccination and local immunomodulatory therapies against murine tumors. While our previously reported glycine-based CART-mRNA complexes (G-CARTs/mRNA) show selective protein expression in the spleen (mouse, >99%), here, we report a new lysine-derived CART-mRNA complex (K-CART/mRNA) that, without additives or targeting ligands, shows selective protein expression in the lungs (mouse, >90%) following systemic IV administration. We further show that by delivering siRNA using the K-CART, we can significantly decrease expression of a lung-localized reporter protein. Blood chemistry and organ pathology studies demonstrate that K-CARTs are safe and well-tolerated. We report on the new step economical, organocatalytic synthesis (two steps) of functionalized polyesters and oligo-carbonate-co-α- aminoester K-CARTs from simple amino acid and lipid-based monomers. The ability to direct protein expression selectively in the spleen or lungs by simple, modular changes to the CART structure opens fundamentally new opportunities in research and gene therapy. 

In acquiring morphology, the language learner faces the challenge of identifying both the form of morphemes and their location within words. For example, individuals acquiring Chamorro (Austronesian) must learn an agreement morpheme with the form -um- that is infixed before the first vowel of the stem (1a). This challenge is more difficult when a morpheme has multiple forms and/or locations: in some varieties of Chamorro, the same agreement morpheme appears as mu- prefixed on verbs beginning with a nasal/liquid consonant (1b). The learner could potentially overcome the acquisition challenge by employing strong inductive biases. This hypothesis is consistent with the typological finding that, across languages, morphemes occupy a restricted set of prosodically-defined locations (Yu, 2007) and there are strong correlations between morpheme form and position (Anderson, 1972). We conducted a series of artificial morphology experiments, modeled after the Chamorro pattern, that provide converging evidence for such inductive biases (Pierrehumbert & Nair, 1995; Staroverov & Finley, 2021). 

Soft materials are usually defined as materials made of mesoscopic entities, often self-organised, sensitive to thermal fluctuations and to weak perturbations. Archetypal examples are colloids, polymers, amphiphiles, liquid crystals, foams. The importance of soft materials in everyday commodity products, as well as in technological applications, is enormous, and controlling or improving their properties is the focus of many efforts. From a fundamental perspective, the possibility of manipulating soft material properties, by tuning interactions between constituents and by applying external perturbations, gives rise to an almost unlimited variety in physical properties. Together with the relative ease to observe and characterise them, this renders soft matter systems powerful model systems to investigate statistical physics phenomena, many of them relevant as well to hard condensed matter systems. Understanding the emerging properties from mesoscale constituents still poses enormous challenges, which have stimulated a wealth of new experimental approaches, including the synthesis of new systems with, e.g. tailored self-assembling properties, or novel experimental techniques in imaging, scattering or rheology. Theoretical and numerical methods, and coarse-grained models, have become central to predict physical properties of soft materials, while computational approaches that also use machine learning tools are playing a progressively major role in many investigations. This Roadmap intends to give a broad overview of recent and possible future activities in the field of soft materials, with experts covering various developments and challenges in material synthesis and characterisation, instrumental, simulation and theoretical methods as well as general concepts. 

To better understand tick ecology in Virginia and the increasing Lyme disease incidence in western Virginia, a comparative phenological study was conducted in which monthly collections were performed at twelve sampling locations in southwestern Virginia (high Lyme disease incidence) and 18 equivalent sampling locations in southeastern Virginia (low Lyme disease incidence) for one year. In western Virginia, we also explored the effect of elevation on collection rates of Ixodes scapularis Say (Acari: Ixodidae) and Amblyomma americanum (L.) (Acari: Ixodidae). In total, 35,438 ticks were collected (33,106 A. americanum; 2,052 I. scapularis; 134 Ixodes affinis Neumann [Acari: Ixodidae]; 84 Dermacentor variabilis [Say] [Acari: Ixodidae]; 49 Dermacentor albipictus [Packard] [Acari: Ixodidae]; 10 Haemaphysalis leporispalustris [Packard] [Acari: Ixodidae]; 2 Ixodes brunneus Koch [Acari: Ixodidae]; 1 Haemaphysalis longicornis Neumann [Acari: Ixodidae]). Within southwestern Virginia, Ixodes scapularis collection rates were not influenced by elevation, unlike A. americanum which were collected more frequently at lower elevations (e.g., below 500 m). Notably, I. scapularis larvae and nymphs were commonly collected in southwestern Virginia (indicating that they were questing on or above the leaf litter) but not in southeastern Virginia. Questing on or above the leaf litter is primarily associated with northern populations of I. scapularis. These findings may support the hypothesis that I. scapularis from the northeastern United States are migrating into western Virginia and contributing to the higher incidence of Lyme disease in this region. This comparative phenological study underscores the value of these types of studies and the need for additional research to further understand the rapidly changing tick-borne disease dynamics in Virginia.

 

The novel electrophilic organo‐tantalum catalyst AlS/TaNp_x(1) (Np=neopentyl) is prepared by chemisorption of the alkylidene Np₃Ta=CH^tBu onto highly Brønsted acidic sulfated alumina (AlS). The proposed catalyst structure is supported by EXAFS, XANES, ICP, DRIFTS, elemental analysis, and SSNMR measurements and is in good agreement with DFT analysis. Catalyst1is highly effective for the hydrogenolysis of diverse linear and branched hydrocarbons, ranging from C2 to polyolefins. To the best of our knowledge,1exhibits one of the highest polyolefin hydrogenolysis activities (9,800 (CH₂units) ⋅ mol(Ta)⁻¹ ⋅ h⁻¹at 200 °C/17 atm H₂) reported to date in the peer‐reviewed literature. Unlike the AlS/ZrNp₂analog, the Ta catalyst is more thermally stable and offers multiple potential C−C bond activation pathways. For hydrogenolysis, AlS/TaNp_xis effective for a wide variety of pre‐ and post‐consumer polyolefin plastics and is not significantly deactivated by standard polyolefin additives at typical industrial concentrations.