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Abstract To mitigate climate change, some seek to store carbon from the atmosphere in agricultural soils. However, our understanding about how agriculture affects soil organic carbon is muddied by studies (1) lacking longitudinal data, (2) ignoring bulk density changes, or (3) sampling only surface soils. To better understand soil organic carbon trends, here we measured changes over 30 years in density-corrected, full-soil-depth (90 cm) soil organic carbon stocks under 6 cropping systems and a restored prairie in a Mollisol of southern Wisconsin, USA. Cash-grain systems and alfalfa-based systems lost soil organic carbon. Prairie and rotationally-grazed pasture maintained soil organic carbon. Average soil organic carbon losses for cash-grain and alfalfa-based systems were −0.80 (±0.12) and −0.54 (±0.13) Mg C ha−1 yr−1, respectively. Sensitivity analysis showed that incomplete methodologies overestimated soil organic carbon improvements. Our findings using more comprehensive methods demonstrate the inadequacy of row-crop systems and the need for well-managed grasslands to protect soil organic carbon in productive agricultural soils of the Upper Midwest USA.

Abstract Background As interest in the voluntary soil carbon market surges, carbon registries have been developing new soil carbon measurement, reporting, and verification (MRV) protocols. These protocols are inconsistent in their approaches to measuring soil organic carbon (SOC). Two areas of concern include the type of SOC stock accounting method (fixed-depth (FD) vs. equivalent soil mass (ESM)) and sampling depth requirement. Despite evidence that fixed-depth measurements can result in error because of changes in soil bulk density and that sampling to 30 cm neglects a significant portion of the soil profile’s SOC stock, most MRV protocols do not specify which sampling method to use and only require sampling to 30 cm. Using data from UC Davis’s Century Experiment (“Century”) and UW Madison’s Wisconsin Integrated Cropping Systems Trial (WICST), we quantify differences in SOC stock changes estimated by FD and ESM over 20 years, investigate how sampling at-depth (> 30 cm) affects SOC stock change estimates, and estimate how crediting outcomes taking an empirical sampling-only crediting approach differ when stocks are calculated using ESM or FD at different depths. Results We find that FD and ESM estimates of stock change can differ by over 100 percent and that, as expected, much of this difference is associated with changes in bulk density in surface soils (e.g., r = 0.90 for Century maize treatments). This led to substantial differences in crediting outcomes between ESM and FD-based stocks, although many treatments did not receive credits due to declines in SOC stocks over time. While increased variability of soils at depth makes it challenging to accurately quantify stocks across the profile, sampling to 60 cm can capture changes in bulk density, potential SOC redistribution, and a larger proportion of the overall SOC stock. Conclusions ESM accounting and sampling to 60 cm (using multiple depth increments) should be considered best practice when quantifying change in SOC stocks in annual, row crop agroecosystems. For carbon markets, the cost of achieving an accurate estimate of SOC stocks that reflect management impacts on soils at-depth should be reflected in the price of carbon credits.

Grazing and hay forage crops reduce erosion compared to annual crops, but few studies have compared soil and nutrient loss among grazing systems compared to a control. We evaluated runoff water quality and nutrient loss among three grazing systems and a hay crop production field with manure application (control) using a paired watershed design. Four edge-of-field sites at a research farm in central Wisconsin were managed as hay during calibration (2013–2018) followed by a grazing treatment phase (2018–2020). Grazing treatments of different stocking methods included continuous stocking (CS), primary paddock stocking (PPS), and adaptive multi-paddock stocking (AMPS). Runoff, sediment, nitrogen (N), and phosphorus (P) loads were monitored year-round. Grazing increased average runoff volume by as much as 1.7-fold depending on stocking method and tended to decrease event mean N and P concentrations. CS had larger mean sediment (2.0-fold), total N (1.9-fold), and total P loads (1.2-fold) compared to the control and had the lowest average pasture forage mass. AMPS had lower N and P loss as a percentage of that applied from manure application/livestock excretion (1.3 and 1.6%, respectively) compared to the control (2.5 and 2.1%), PPS (2.5 and 2.6%), and CS (3.2 and 3.0%). Stocking method had a marked impact on nutrient loss in runoff from these systems, suggesting water quality models should account for pasture management, but nutrient losses from all perennial forage systems were small relative to previous data from annual cropping systems.

Understanding the role of chemokine receptors in health and disease has been of increasing interest in recent years. Chemokine receptor CXCR4 has been extensively studied because of its defined role in immune cell trafficking, HIV infection, inflammatory diseases, and cancer progression. We have developed high affinity rigidified CXCR4 antagonists that incorporate metal ions to optimize the binding interactions with the aspartate side chains at the extracellular surface of the CXCR4 chemokine receptor and increase the residence time. Cross- and side-bridged tetraazamacrocylic complexes offer significant advantages over the non-bridged molecular structures in terms of receptor affinity, potential for radiolabelling, and use in therapeutic applications. Our investigation has been extended to the influence of the ring size on bridged tetraazamacrocyclic compounds with the addition of two novel chelators (bis-cross-bridged homocyclen and bis-cross-bridged cyclen) to compare to the bis-bridged cyclam, along with novel metal complexes formed with copper(II) or zinc(II). The in vitro biological assays showed that all of the zinc(II) complexes are high affinity antagonists with a marked increase in CXCR4 selectivity for the bis-cross-bridged cyclen complex, whereas the properties of the copper(II) complexes are highly dependent on metal ion geometry. X-ray crystal structural data and DFT computational studies allow for the rationalisation of the relative affinities and the aspartate residue interactions on the protein surface. Changing the ring size from 14-membered can increase the selectivity for the CXCR4 receptor whilst retaining potent inhibitory activity, improving the key pharmacological characteristics.

Background: Tourette syndrome is a neurodevelopmental movement disorder involving basal ganglia dysfunction. PDE10A inhibitors modulate signaling in the striatal basal ganglia nuclei and are thus of interest as potential therapeutics in treating Tourette syndrome and other movement disorders. Methods: The preclinical pharmacology and toxicology, human safety and tolerability, and human PET striatal enzyme occupancy data for the PDE10A inhibitor EM-221 are presented. Results: EM-221 inhibited PDE10A with an in vitro IC50 of 9 pM and was >100,000 selective vs. other PDEs and other CNS receptors and enzymes. In rats, at doses of 0.05–0.50 mg/kg, EM-221 reduced hyperlocomotion and the disruption of prepulse inhibition induced by MK-801, attenuated conditioned avoidance, and facilitated novel object recognition, consistent with PDE10A’s inhibition. EM-221 displayed no genotoxicity and was well tolerated up to 300 mg/kg in rats and 100 mg/kg in dogs. In single- and multiple-day ascending dose studies in healthy human volunteers, EM-221 was well tolerated up to 10 mg, with a maximum tolerated dose of 15 mg. PET imaging indicated that a PDE10A enzyme occupancy of up to 92.8% was achieved with a ~24 h half-life. Conclusions: The preclinical and clinical data presented here support the study of EM-221 in phase 2 trials of Tourette syndrome and other movement disorders.

Abstract Soil health can differ across cropping systems because of variation in edaphic and management factors. We evaluated how biological indicators of soil health (soil organic matter [SOM], permanganate oxidizable carbon [POXC], mineralizable carbon [MinC], autoclaved‐citrate‐extractable [ACE] protein, and potentially mineralizable nitrogen [PMN]) compared across four common Wisconsin cropping systems: grazed cool‐season pastures, forage‐based rotations that included perennial legumes or grasses, annual rotations receiving manure, and annual rotations receiving synthetic fertilizers. Biological indicators of soil health were up to 195% greater in pastures than other cropping systems. MinC, POXC and PMN were 10%–90% greater in forage‐based rotations than annual cropping systems, but only MinC and POXC were greater in annual systems with manure compared to those without manure by 35% and 7%, respectively. Perennial vegetation and livestock integration offer the greatest potential to increase biological indicators of soil health in agricultural lands.

Livestock agriculture must change to meet demand for food production while building soil, reducing flooding, retaining nutrients, enhancing biodiversity, and supporting thriving communities. Technological innovations, including those in digital and precision agriculture, are unlikely by themselves to create the magnitude and directionality of transformation of livestock production systems that are needed. We begin by comparing technological, ecological and social innovations in feedlot-finished and pasture-finished cattle production and propose that what is required is a more integrative ‘agroecological innovation’ process that intentionally weaves these three forms of innovation to transition livestock agriculture to be genuinely regenerative and multifunctional. This integrated system emphasizes social innovations as essential components of the innovation system because of their capacity to address and influence the social context into which technological and ecological innovations occur. In particular, regional place-making can be especially useful as an interactive process of designing regional identities as people engage with one another and their environments to define landscape futures and the related social standards that normalize particular land management practices. Intentionally developing innovations can help communities engage in relational place-making processes to define desired outcomes for agricultural landscapes and develop ways to collaborate towards achieving them, including the creation of novel supply chains that support regenerative livestock systems. As social norms evolve through place-making they influence individual behaviors and agricultural practices on the ground and offer a pathway for more rapid scaling of regenerative practices in livestock agriculture. Regional place-making also can influence the ‘meta’ context of agricultural systems by engaging with public and private institutions responsible for management of natural resources, food systems, and the public good, further accelerating the scaling process. Emerging agroecological innovation systems for livestock agriculture must be designed and governed in ways that ensure responsible and diverse outcomes compatible with their social and ecological contexts, and with management approaches and technologies consistent with the values and goals of communities in a region.

Perennial grasslands, including prairie and pasture, have declined with tremendous environmental and social costs. This decline reflects unequal policy support for grasslands and managed grazing compared to row crops. To create a resource for community partners and decision-makers, we reviewed and analyzed the policy tools and implementation capacity that supports and constrains grasslands and managed grazing in the U.S. Upper Midwest. Risk reduction subsidies for corn and soybeans far outpace the support for pasture. Some states lost their statewide grazing specialist when the federal Grazing Lands Conservation Initiative lapsed. The United States Department of Agriculture, Natural Resources Conservation Service support for lands with prescribed grazing practices declined after 2005 but remained relatively steady 2010–2020. These results reveal the policy disadvantage for grasslands and managed grazing in comparison with row crop agriculture for milk and meat production. Grassland and grazing policies have an important nexus with water quality, biodiversity, carbon and outdoor recreation policy. Socially just transitions to well-managed, grazed grasslands require equity-oriented interventions that support community needs. We synthesized recommendations for national and state policy that farmers and other grazing professionals assert would support perennial grasslands and grazing, including changes in insurance, conservation programs, supply chains, land access, and fair labor. These policies would provide critical support for grass-based agriculture and prairies that we hope will help build soil, retain nutrients, reduce flooding and enhance biodiversity while providing healthy food, jobs, and communities.

Dominant forms of agricultural production in the U.S. Upper Midwest are undermining human health and well being. Restoring critical ecosystem functions to agriculture is key to stabilizing climate, reducing flooding, cleaning water, and enhancing biodiversity. We used simulation models to compare ecosystem functions (food-energy production, nutrient retention, and water infiltration) provided by vegetation associated with continuous corn, corn-soybean rotation, and perennial grassland producing feed for dairy livestock. Compared to continuous corn, most ecosystem functions dramatically improved in the perennial grassland system (nitrate leaching reduced ~90%, phosphorus loss reduced ~88%, drainage increased ~25%, evapotranspiration reduced ~29%), which will translate to improved ecosystem services. Our results emphasize the need to incentivize multiple ecosystem services when managing agricultural landscapes.

The Fall Midwater Trawl (FMWT) Survey has been conducted near continuously since 1967 to assess the abundance and distribution of pelagic fish species throughout the San Francisco Bay/Sacramento-San Joaquin estuary (Bay Delta). For most of this period, sampling 100 core stations provided data for abundance and distribution analyses. Another 22 (non-core) stations were added to the FMWT 8 to 28 years ago to supplement the original 100 (core) stations. However, relative abundance indices are published annually from only the data collected at the core stations. Here we incorporate data from non-core stations along with core station data to calculate an alternative index that also integrates modern estimates of water volume within the Bay Delta into an index calculation. The use of data from non-core stations in calculating the alternative index was particularly useful for American Shad (Alosa sapidissima) and Threadfin Shad (Dorosoma petenense). Consistently high catches at non-core stations for a couple species and modest catches for a couple additional species highlight the value of these additional catch data for our understanding of how fishes are distributed in the estuary.

The density and quality of zooplankton prey affect the feeding success of larval and juvenile fishes and thus can drive growth, survival, and recruitment. As part of a larger effort investigating potential causes of a pelagic fish decline, we examined regional feeding success (food presence/absence, stomach fullness), diet composition and prey selection of young Longfin Smelt (Spirinchus thaleichthys) in spring and summer as a function of fish size and prey availability in the San Francisco Estuary. We conducted our sampling during two wet and two dry years, because weather and river flow influence prey community composition and location. Larval and juvenile fish showed evidence of food limitation: high proportions of empty stomachs (≤ 70%) and stomach contents totaling

We describe a pre-clinical spinal cord motor neuron injury model that is minimal invasive, reproducible, focal and easily applied to small rodents. Retrograde axonal transport of a pro-apoptotic phosphatidylinosotol 3’-kinase inhibitor, wortmannin, via the sciatic nerve results in loss of ipsilateral lumbar motor neurons proportional to the level of drug administered. Motor neuron loss was detected by choline acetyltransferase (ChAT) immunostaining and with a transgenic thy1-eGFP marker. The short half-life of wortmannin generates minimal wound spread, and wortmannin does not affect axon transport, as determined by co-injection of a pseudorabies virus tracer. Using quantitative transcript analysis, we found that ChAT transcripts significantly decreased at 14 days post-delivery of 1 μg wortmannin, relative to sham controls, and remained low after 90 days. Smaller effects were observed with 200 ng and 100 ng wortmannin. Wortmannin also generated a transient and significant increase in astrocyte Gfap transcripts after 14 days with a return to control levels at 90 days. Treated mice had hind limb spasticity and a forced motor function defect that was quantified using a water exit test. Controls rapidly exit a shallow water tray, and wortmannin treated animals were up to 12-fold slower, a phenotype that persisted for at least 3 months. Thus the focal delivery of wortmannin to motor neurons generates a reproducible and scalable injury that can facilitate quantitative studies on neural regeneration and repair. The efficacy of sciatic nerve suicide transport can also explain neurotoxin-mediated selective loss of motor neurons in diseases such as amyotrophic lateral sclerosis. All procedures were performed at Rutgers under established Institutional Animal Care and Use protocols (eIACUC_TR201800022, approved on March 20, 2018).

Abstract Background Lack of sustainable access to clean drinking water continues to be an issue of paramount global importance, leading to millions of preventable deaths annually. Best practices for providing sustainable access to clean drinking water, however, remain unclear. Widespread installation of low-cost, in-home, point of use water filtration systems is a promising strategy. Methods We conducted a prospective, randomized, controlled trial whereby 16 villages were selected and randomly assigned to one of four treatment arms based on the installation location of Sawyer® PointONE™ filters (filter in both home and school; filter in home only; filter in school only; control group). Water samples and self-reported information on diarrhea were collected at multiple times throughout the study. Results Self-reported household prevalence of diarrhea decreased from 25.6 to 9.76% from installation to follow-up (at least 7 days, and up to 200 days post-filter installation). These declines were also observed in diarrhea with economic or educational consequences (diarrhea which led to medical treatment and/or missing school or work) with baseline prevalence of 9.64% declining to 1.57%. Decreases in diarrhea prevalence were observed across age groups. There was no evidence of a loss of efficacy of filters up to 200 days post-filter installation. Installation of filters in schools was not associated with decreases in diarrhea prevalence in school-aged children or family members. Unfiltered water samples both at schools and homes contained potential waterborne bacterial pathogens, dissolved heavy metals and metals associated with particulates. All dissolved metals were detected at levels below World Health Organization action guidelines. Conclusions This controlled trial provides strong evidence of the effectiveness of point-of-use, hollow fiber membrane filters at reducing diarrhea from bacterial sources up to 200 days post-installation when installed in homes. No statistically significant reduction in diarrhea was found when filters were installed in schools. Further research is needed in order to explore filter efficacy and utilization after 200 days post-installation. Trial registration ClinicalTrials.gov, NCT03972618 . Registered 3 June 2019—retrospectively registered.

Abstract The U.S. grain‐finished beef system is highly productive but has many negative consequences for human health and well‐being because it pollutes surface and groundwaters, exacerbates flooding, reduces biodiversity, and contributes to climate change. Moving the entire U.S. grain‐fed beef production system to a grass‐finished system is possible without displacing food production and under conservative soil carbon (C) change estimates would result in a reduced but similar C footprint, while improving soil health, water quality, and biodiversity. More optimistic estimates for soil C accumulation indicate the system would result in significant atmospheric C drawdown. Agroecological transformation like this is limited only by our imagination and policies that incentivize agriculture for the public good rather than profits for a few.

The popularity of forensic science television programs has created a hiring challenge for forensic science laboratories. Laboratories receive unprecedented numbers of applicants, yet struggle to identify highly-qualified candidates. Forensic examiners must possess a unique set of knowledge, skills, and abilities (KSAs) plus other characteristics. They must be critical thinkers, detail-oriented, decisive, and self-regulated; be able to communicate clearly and effectively within the laboratory, with customers (typically investigators or attorneys), and in the courtroom; and demonstrate the required core competencies. Currently, no validated instruments, standardized job descriptions, or lists of KSAs exist to aid in forensic science personnel recruitment and assessment, often resulting in high turnover leading to costly new recruitment and training cycles. This article describes how industrial/organizational psychology develops methods and tools to improve workforce selection; describes some tools currently in use in forensic science; and advocates for research and development of better tools for use in forensic science.

We present two decades of new high-angular-resolution near-infrared data from the W. M. Keck Observatory that reveal extreme evolution in X7, an elongated dust and gas feature, presently located half an arcsecond from the Galactic Center supermassive black hole. With both spectro-imaging observations of Br- γ line emission and Lp (3.8 μ m) imaging data, we provide the first estimate of its orbital parameters and quantitative characterization of the evolution of its morphology and mass. We find that the leading edge of X7 appears to be on a mildly eccentric ( e ∼ 0.3), relatively short-period (170 yr) orbit and is headed toward periapse passage, estimated to occur in ∼2036. Furthermore, our kinematic measurements rule out the earlier suggestion that X7 is associated with the stellar source S0-73 or with any other point source that has overlapped with X7 during our monitoring period. Over the course of our observations, X7 has (1) become more elongated, with a current length-to-width ratio of 9, (2) maintained a very consistent long-axis orientation (position angle of 50°), (3) inverted its radial velocity differential from tip to tail from −50 to +80 km s ^−1 , and (4) sustained its total brightness (12.8 Lp magnitudes at the leading edge) and color temperature (425 K), which suggest a constant mass of ∼50 M _Earth . We present a simple model showing that these results are compatible with the expected effect of tidal forces exerted on it by the central black hole, and we propose that X7 is the gas and dust recently ejected from a grazing collision in a binary system.

Abstract Ants play multiple roles in ecosystems, but their ability to affect decomposition processes in temperate grasslands is relatively unknown. We investigated whether the suppression of ant populations influenced litter decomposition in grasslands via predation of some decomposers (e.g., mites and springtails) and/or microbial activity and composition. We performed two successful ant suppression treatments (seven weeks, 37% suppression, year 1, 10 weeks, 70% suppression, year 2) over the course of a 59‐week experiment. We then assayed the effects of ant suppression using coarse‐ and fine‐mesh litterbags and evaluated litter chemistry, microbial and arthropod communities, and microbial enzyme activity. Ant suppression efforts reduced ant abundance and altered ant, arthropod decomposer, and non‐ant predator community composition. However, ant suppression did not affect decomposer arthropod abundance, litter mass loss, microbial composition, or enzyme activity in litterbags. Litterbag mesh size did not alter microbial composition, perhaps due to a failure to exclude decomposers, as mites and springtails were more or equally abundant in fine‐mesh bags. Nevertheless, mesh size did change litter chemistry, suggesting that mesh size‐mediated microenvironments affect decomposition environment regardless of invertebrate exclusion. Coarse‐mesh litterbags had higher concentrations of microbial sugars, lignin, and N and lower concentrations of litter C and crystalline cellulose than fine‐mesh litterbags. Litterbag mesh size may alter decomposition processes irrespective of invertebrate abundance. We found no evidence that ant predation was an important driver of decomposer populations or decomposition in these systems, and we suspect redundancy at the top of the detrital food web dilutes the role of ants.

Additive manufacturing (AM) techniques have been widely used to fabricate structural components with complex geometries. Understanding AM materials under extreme environments is crucial for their implementation in various engineering sectors. In this study, the deformation behavior and irradiation damage of 316 L stainless steel (SS) fabricated by the direct energy deposition (DED) process are investigated. The fabrication-induced nanopores with an average diameter of 200 nm exhibit a core-shell structure with a local tensile strain. The precession electron diffraction (PED) reveals that austenite-to-martensite phase transformation preferentially occurs around the nanopores under tension test at room temperature. Proton irradiation experiments performed at 360 °C to a fluence of 1.09 × 1019 cm−2 and 5.42 × 1019 cm−2 show that the DED fabricated 316 L SS exhibits a stronger void-swelling resistance and lower dislocation loop density than its wrought counterpart. AM-induced features, such as nanopores and sub-grain boundaries, could serve as defect sinks to absorb irradiation-induced defects. The design of microstructure using AM processes opens up new avenues for the development of irradiation tolerant materials for nuclear applications.

Abstract Background Pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive neurodegenerative disorder with brain iron accumulation (NBIA). Objectives To assess PKAN diagnostic pathway, history, and burden across the spectrum of PKAN severity from patient and/or caregiver perspectives. Methods Caregivers of patients (n = 37) and patients themselves (n = 2) were interviewed in a validation study of the PKAN-Activities of Daily Living (ADL) scale. The current study used quartiles of the PKAN-ADL total score to divide patients by severity of impairment (Lowest, Second Lowest, Third Lowest, Highest). Diagnostic and treatment history, healthcare utilization, disease burden, and caregiver experience were compared between groups. Results The analyses included data from 39 patients. Mean age at PKAN symptom onset (P = 0.0007), initial MRI (P = 0.0150), and genetic testing (P = 0.0016) generally decreased across the PKAN severity spectrum. The mean duration of illness did not differ among PKAN severity groups (range, 9.7–15.2 years; P = 0.3029). First MRI led to diagnosis in 56.4% of patients (range, 30.0–90.0%). A mean (SD) of 13.0 (13.1) medical and 55.2 (78.5) therapy visits (eg, physical, speech) occurred in the past year. More patients in the higher PKAN severity groups experienced multiple current functional losses and/or earlier onset of problems (P-values

Abstract Nitrous oxide (N2O) is a potent greenhouse gas and major component of the net global warming potential of bioenergy feedstock cropping systems. Numerous environmental factors influence soil N2O production, making direct correlation difficult to any one factor of N2O fluxes under field conditions. We instead employed quantile regression to evaluate whether soil temperature, water‐filled pore space (WFPS), and concentrations of soil nitrate (NO3−) and ammonium (NH4+) determined upper bounds for soil N2O flux magnitudes. We collected data over 6 years from a range of bioenergy feedstock cropping systems including no‐till grain crops, perennial warm‐season grasses, hybrid poplar, and polycultures of tallgrass prairie species each with and without nitrogen (N) addition grown at two sites. The upper bounds for soil N2O fluxes had a significant and positive correlation with all four environmental factors, although relatively large fluxes were still possible at minimal values for nearly all factors. The correlation with NH4+ was generally weaker, suggesting it is less important than NO3− in driving large fluxes. Quantile regression slopes were generally lower for unfertilized perennials than for other systems, but this may have resulted from a perpetual state of nitrogen limitation, which prevented other factors from being clear constraints. This framework suggests efforts to reduce concentrations of NO3− in the soil may be effective at reducing high‐intensity periods—”hot moments”—of N2O production.

Abstract Ecosystem responses to external inputs of nutrients and organisms are highly variable. Theory predicts that ecosystem traits will determine the responses to spatial subsidies, but evidence for how vegetation structure can modulate those effects is lacking. We investigated how vegetation structure (i.e., leaf area index [LAI] and vegetation height) influenced the ecosystem and community responses to insect spatial subsidies in a subarctic grassland. Our experiment consisted of a 2 × 2 manipulation where in one treatment we either blocked flying insects over a 2‐yr period in 1‐m2 plots near the shore of Lake Mývatn, Iceland, where deposition of aquatic adult midges (Diptera: Chironomidae) to land is high, or left control plots accessible to flying midges. In the second treatment, grassland vegetation was cut (tall vs. short) at the start of each season and then allowed to regrow. We then measured litter decomposition and arthropod composition and density within each plot (n = 6 replicates × 4 treatments). Midge‐exclusion cages reduced midge deposition by 81% relative to the open plots. Vegetation cutting initially reduced LAI and vegetation height by 3× and 1.5×, respectively, but these were not different by the end of the second‐growing season. We found that vegetation structure modulated the effects of midge subsides on litter decomposition, with taller canopies intercepting more insect subsidies than shorter ones, leading to 18% faster litter decomposition. In contrast, the short‐vegetation plots intercepted fewer subsidies and had higher temperatures and sunlight, resulting in no effects of midges on decomposition. However, by the end of the experiment when all vegetation structure characteristics had converged across all plots, we found no differences in decomposition between treatments. The effects of midge subsidies on arthropod composition depended on the vegetation structure, suggesting that arthropods might also be responding to the structural effects on spatial subsidies. Our findings indicate that vegetation structure can modify the abiotic environment and the quantity of subsidies entering a recipient ecosystem as aerial insects, resulting in ecosystem‐ and community‐level responses. Thus, changing vegetation structure via habitat disturbances will likely have important implications for ecosystem functions that rely on spatial subsidies.

Multiple mechanisms contribute to the generation, propagation, and coordination of the rhythmic patterns necessary for locomotion in Caenorhabditis elegans. Current experiments have focused on two possibilities: pacemaker neurons and stretch-receptor feedback. Here, we focus on whether it is possible that a chain of multiple network rhythmic pattern generators in the ventral nerve cord also contribute to locomotion. We use a simulation model to search for parameters of the anatomically constrained ventral nerve cord circuit that, when embodied and situated, can drive forward locomotion on agar, in the absence of pacemaker neurons or stretch-receptor feedback. Systematic exploration of the space of possible solutions reveals that there are multiple configurations that result in locomotion that is consistent with certain aspects of the kinematics of worm locomotion on agar. Analysis of the best solutions reveals that gap junctions between different classes of motorneurons in the ventral nerve cord can play key roles in coordinating the multiple rhythmic pattern generators.

The clinical importance of microbiomes to the chronicity of wounds is widely appreciated, yet little is understood about patient-specific processes shaping wound microbiome composition. Here, a two-cohort microbiome-genome wide association study is presented through which patient genomic loci associated with chronic wound microbiome diversity were identified. Further investigation revealed that alternative TLN2 and ZNF521 genotypes explained significant inter-patient variation in relative abundance of two key pathogens, Pseudomonas aeruginosa and Staphylococcus epidermidis. Wound diversity was lowest in Pseudomonas aeruginosa infected wounds, and decreasing wound diversity had a significant negative linear relationship with healing rate. In addition to microbiome characteristics, age, diabetic status, and genetic ancestry all significantly influenced healing. Using structural equation modeling to identify common variance among SNPs, six loci were sufficient to explain 53% of variation in wound microbiome diversity, which was a 10% increase over traditional multiple regression. Focusing on TLN2, genotype at rs8031916 explained expression differences of alternative transcripts that differ in inclusion of important focal adhesion binding domains. Such differences are hypothesized to relate to wound microbiomes and healing through effects on bacterial exploitation of focal adhesions and/or cellular migration. Related, other associated loci were functionally enriched, often with roles in cytoskeletal dynamics. This study, being the first to identify patient genetic determinants for wound microbiomes and healing, implicates genetic variation determining cellular adhesion phenotypes as important drivers of infection type. The identification of predictive biomarkers for chronic wound microbiomes may serve as risk factors and guide treatment by informing patient-specific tendencies of infection.

C. elegans locomotes in an undulatory fashion, generating thrust by propagating dorsoventral bends along its body. Although central pattern generators (CPGs) are typically involved in animal locomotion, their presence in C. elegans has been questioned, mainly because there has been no evident circuit that supports intrinsic network oscillations. With a fully reconstructed connectome, the question of whether it is possible to have a CPG in the ventral nerve cord (VNC) of C. elegans can be answered through computational models. We modeled a repeating neural unit based on segmentation analysis of the connectome. We then used an evolutionary algorithm to determine the unknown physiological parameters of each neuron so as to match the features of the neural traces of the worm during forward and backward locomotion. We performed 1,000 evolutionary runs and consistently found configurations of the neural circuit that produced oscillations matching the main characteristic observed in experimental recordings. In addition to providing an existence proof for the possibility of a CPG in the VNC, we suggest a series of testable hypotheses about its operation. More generally, we show the feasibility and fruitfulness of a methodology to study behavior based on a connectome, in the absence of complete neurophysiological details. Despite the relative simplicity of C. elegans, its locomotion machinery is not yet well understood. We focus on the generation of dorsoventral body bends. Although network central pattern generators are commonly involved in animal locomotion, their presence in C. elegans has been questioned due to a lack of an evident neural circuit to support it. We developed a computational model grounded in the available neuroanatomy and neurophysiology, and we used an evolutionary algorithm to explore the space of possible configurations of the circuit that matched the neural traces observed during forward and backward locomotion in the worm. Our results demonstrate that it is possible for the rhythmic contraction to be produced by a circuit present in the ventral nerve cord.

Patients with vascular Ehlers–Danlos syndrome (vEDS) have a defect in the formation of type III collagen. This defect puts patients at risk of vascular rupture, uterine rupture, and bowel perforations. The segmental absence of intestinal musculature is a rare histopathologic finding, wherein there is a lack of a muscularis propria layer in the intestinal wall. Although typically documented in the literature in neonates or adults, it can be seen in children of other ages. This is a case report of a patient who exhibits both rare entities, which has not been described in the literature to date.

A thin elastic sheet can develop wrinkles which arrange into patterns similar to those characteristic of liquid crystals. Here the authors use this analogy to propose a mapping between the elastic sheet problem and the smectic liquid crystal problem which can enable a better understanding of wrinkling.

When particle-laden drops evaporate, coffee ring patterns form which can affect particle deposition. Here Davidsonet al. show that unlike previously investigated drops, the flows in drying drops of liquid crystals are driven by an increase in surface tension due to liquid crystal concentration.

While much is known about acute infection pathogenesis, the understanding of chronic infections has lagged. Here we sought to identify the genes and functions that mediate fitness of the pathogen Pseudomonas aeruginosa in chronic wound infections, and to better understand the selective environment in wounds. We found that clinical isolates from chronic human wounds were frequently defective in virulence functions and biofilm formation, and that many virulence and biofilm formation genes were not required for bacterial fitness in experimental mouse wounds. In contrast, genes involved in anaerobic growth, some metabolic and energy pathways, and membrane integrity were critical. Consistent with these findings, the fitness characteristics of some wound impaired-mutants could be represented by anaerobic, oxidative, and membrane-stress conditions ex vivo, and more comprehensively by high-density bacterial growth conditions, in the absence of a host. These data shed light on the bacterial functions needed in chronic wound infections, the nature of stresses applied to bacteria at chronic infection sites, and suggest therapeutic targets that might compromise wound infection pathogenesis.

Chronic wound infections are increasingly recognized to be dynamic and polymicrobial in nature, necessitating the development of wound models which reflect the complexities of infection in a non-healing wound. Wound slough isolated from human chronic wounds and transferred to mice was recently shown to create polymicrobial infection in mice, and there is potential this tool may be improved by cryogenic preservation. The purpose of this study was to investigate the application of cryogenic preservation to transferring polymicrobial communities, specifically by quantifying the effects of cryopreservation and wound microbiome transplantation. Slough from an established murine polymicrobial surgical excision model and five patients were subjected to three preservation strategies: refrigeration until infection, freezing in liquid nitrogen, or freezing in liquid nitrogen with glycerol solution prior to infection in individual mice. Four days following inoculation onto mice, wound microbiota were quantified using either culture isolation or by 16s rRNA gene community profiling and quantitative PCR. Cryogenic preservation did not significantly reduce bacterial viability. Reestablished microbial communities were significantly associated with patient of origin as well as host context (i.e., originally preserved from a patient versus mouse infection). Whereas preservation treatment did not significantly shape community composition, the transfers of microbiomes from human to mouse were characterized by reduced diversity and compositional changes. These findings indicated that changes should be expected to occur to community structure after colonization, and that compositional change is likely due to the rapid change in infection context as opposed to preservation strategy. Furthermore, species that were present in higher relative abundance in wound inoculate were more likely to colonize subsequent wounds, and wound inoculate with higher bacterial load established wound communities that were more compositionally similar. Results inform expectations for the complementation of chronic wound in vivo modeling with cryogenic preservation archives.

Abstract Greenhouse gas (GHG) emissions from soils are a key sustainability metric of cropping systems. During crop establishment, disruptive land‐use change is known to be a critical, but under reported period, for determining GHG emissions. We measured soil N2O emissions and potential environmental drivers of these fluxes from a three‐year establishment‐phase bioenergy cropping systems experiment replicated in southcentral Wisconsin (ARL) and southwestern Michigan (KBS). Cropping systems treatments were annual monocultures (continuous corn, corn–soybean–canola rotation), perennial monocultures (switchgrass, miscanthus, and poplar), and perennial polycultures (native grass mixture, early successional community, and restored prairie) all grown using best management practices specific to the system. Cumulative three‐year N2O emissions from annuals were 142% higher than from perennials, with fertilized perennials 190% higher than unfertilized perennials. Emissions ranged from 3.1 to 19.1 kg N2O‐N ha−1 yr−1 for the annuals with continuous corn > corn–soybean–canola rotation and 1.1 to 6.3 kg N2O‐N ha−1 yr−1 for perennials. Nitrous oxide peak fluxes typically were associated with precipitation events that closely followed fertilization. Bayesian modeling of N2O fluxes based on measured environmental factors explained 33% of variability across all systems. Models trained on single systems performed well in most monocultures (e.g., R2 = 0.52 for poplar) but notably worse in polycultures (e.g., R2 = 0.17 for early successional, R2 = 0.06 for restored prairie), indicating that simulation models that include N2O emissions should be parameterized specific to particular plant communities. Our results indicate that perennial bioenergy crops in their establishment phase emit less N2O than annual crops, especially when not fertilized. These findings should be considered further alongside yield and other metrics contributing to important ecosystem services.

Traditional origami structures can be continuously deformed back to a flat sheet of paper, while traditional kirigami requires glue or seams in order to maintain its rigidity. In the former, nontrivial geometry can be created through overfolding paper, while in the latter, the paper topology is modified. Here we propose a hybrid approach that relies on overlapped flaps that create in-plane compression resulting in the formation of polyhedra composed of freely supported plates. Not only are these structures self-locking, but they have colossal load-to-weight ratios of order 10^{4}.

The North American prairie covered about 3.6 million-km2 of the continent prior to European contact. Only 1–2% of the original prairie remains, but the soils that developed under these prairies are some of the most productive and fertile in the world, containing over 35% of the soil carbon in the continental United States. Cultivation may alter microbial diversity and composition, influencing the metabolism of carbon, nitrogen, and other elements. Here, we explored the structure and functional potential of the soil microbiome in paired cultivated-corn (at the time of sampling) and never-cultivated native prairie soils across a three-states transect (Wisconsin, Iowa, and Kansas) using metagenomic and 16S rRNA gene sequencing and lipid analysis. At the Wisconsin site, we also sampled adjacent restored prairie and switchgrass plots. We found that agricultural practices drove differences in community composition and diversity across the transect. Microbial biomass in prairie samples was twice that of cultivated soils, but alpha diversity was higher with cultivation. Metagenome analyses revealed denitrification and starch degradation genes were abundant across all soils, as were core genes involved in response to osmotic stress, resource transport, and environmental sensing. Together, these data indicate that cultivation shifted the microbiome in consistent ways across different regions of the prairie, but also suggest that many functions are resilient to changes caused by land management practices – perhaps reflecting adaptations to conditions common to tallgrass prairie soils in the region (e.g., soil type, parent material, development under grasses, temperature and rainfall patterns, and annual freeze-thaw cycles). These findings are important for understanding the long-term consequences of land management practices to prairie soil microbial communities and their genetic potential to carry out key functions.

Associative N fixation (ANF), the process by which dinitrogen gas is converted to ammonia by bacteria in casual association with plants, has not been well-studied in temperate ecosystems. We examined the ANF potential of switchgrass (Panicum virgatum L.), a North American prairie grass whose productivity is often unresponsive to N fertilizer addition, via separate short-term 15N2 incubations of rhizosphere soils and excised roots four times during the growing season. Measurements occurred along N fertilization gradients at two sites with contrasting soil fertility (Wisconsin, USA Mollisols and Michigan, USA Alfisols). In general, we found that ANF potentials declined with long-term N addition, corresponding with increased soil N availability. Although we hypothesized that ANF potential would track plant N demand through the growing season, the highest root fixation rates occurred after plants senesced, suggesting that root diazotrophs exploit carbon (C) released during senescence, as C is translocated from aboveground tissues to roots for wintertime storage. Measured ANF potentials, coupled with mass balance calculations, suggest that ANF appears to be an important source of N to unfertilized switchgrass, and, by extension, to temperate grasslands in general.

Objective. Pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive disorder with variable onset, rate of progression, and phenotypic expression. Later-onset, more slowly progressive PKAN often presents with neuropsychiatric as well as motor manifestations that include speech difficulties, progressive dystonia, rigidity, and parkinsonism. PKAN is caused by biallelic PANK2 mutations, a gene that encodes pantothenate kinase 2, a regulatory enzyme in coenzyme A biosynthesis. Current therapeutic strategies rely on symptomatic relief. We describe the treatment of the first, later-onset PKAN patient with oral fosmetpantotenate (previously known as RE-024), a novel replacement therapy developed to bypass the enzymatic defect. Methods. This was an open-label, uncontrolled, 12-month treatment with fosmetpantotenate of a single patient with a later-onset, moderately severe, and slowly progressive form of PKAN. Results. The patient showed improvement in all clinical parameters including the Unified Parkinson’s Disease Rating Scale (UPDRS), Barry-Albright Dystonia Scale, the EuroQol five-dimensional three-level (EQ-5D-3L) scale, timed 25-foot walk test, and electroglottographic speech analysis. Fosmetpantotenate was well-tolerated with only transient liver enzyme elevation which normalized after dose reduction and did not recur after subsequent dose increases. Conclusions. Fosmetpantotenate showed promising results in a single PKAN patient and should be further studied in controlled trials.

Diadromy affords fish access to productive ecosystems, increasing growth and ultimately fitness, but it is unclear whether these advantages persist for species migrating within highly altered habitat. Here, we compared the foraging success of wild Delta Smelt-an endangered, zooplanktivorous, annual, semi-anadromous fish that is endemic to the highly altered San Francisco Estuary (SFE)-collected from freshwater (