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Abstract Farmers need accurate estimates of winter cover crop biomass to make informed decisions on termination timing or to estimate potential release of nitrogen from cover crop residues to subsequent cash crops. Utilizing data from an extensive experiment across 11 states from 2016 to 2020, this study explores the most reliable predictors for determining cereal rye cover crop biomass at the time of termination. Our findings demonstrate a strong relationship between early‐season and late‐season cover crop biomass. Employing a random forest model, we predicted late‐season cereal rye biomass with a margin of error of approximately 1,000 kg ha−1 based on early‐season biomass, growing degree days, cereal rye planting and termination dates, photosynthetically active radiation, precipitation, and site coordinates as predictors. Our results suggest that similar modeling approaches could be combined with remotely sensed early‐season biomass estimations to improve the accuracy of predicting winter cover crop biomass at termination for decision support tools. Core Ideas Cereal rye winter cover crop biomass modeled on data from 35 site‐years. We found a strong relationship between early and late‐season biomass. Random forest model with early‐season biomass and weather data performed well. Similar approach could improve decision support tools for cover crop management.

Abstract Objectives Lemniscal (motor‐related) and spinothalamic (neuropathic pain‐related) somatosensory abnormalities affect different subsets of adults with cerebral palsy (CP). Lemniscal/motor abnormalities are associated with posterior thalamic radiation white matter disruption in individuals with CP and white matter injury. We tested the hypothesis that neuropathic pain symptoms in this population are rather associated with injury of the somatosensory (posterior group nuclei) thalamus. Methods In this cross‐sectional study, communicative adults with CP and bilateral white matter injury and neurotypical control participants volunteered to self‐report pain symptoms and undergo research MRI. Posterior group thalamic nuclei volume was computed and correlated against neuropathic pain scores. Results Participants with CP (n = 6) had, on average, 24% smaller posterior group thalamic volumes (95% CI: [10%–39%]; corrected p = 0.01) than control participants. More severe volume loss was correlated with more severe neuropathic pain scores (ρ = −0.87 [−0.99, −0.20]; p = 0.02). Interpretation Association with thalamic volume loss suggests that neuropathic pain in adults with CP may frequently be central neuropathic pain. Complementing assessments of white matter microstructure, regional brain volumes hold promise as diagnostic biomarkers for central neuropathic pain in individuals with structural brain disorders.

Abstract Sea‐level rise (SLR) will cause coastal groundwater to rise in many coastal urban environments. Inundation of contaminated soils by groundwater rise (GWR) will alter the physical, biological, and geochemical conditions that influence the fate and transport of existing contaminants. These transformed products can be more toxic and/or more mobile under future conditions driven by SLR and GWR. We reviewed the vulnerability of contaminated sites to GWR in a US national database and in a case comparison with the San Francisco Bay region to estimate the risk of rising groundwater to human and ecosystem health. The results show that 326 sites in the US Superfund program may be vulnerable to changes in groundwater depth or flow direction as a result of SLR, representing 18.1 million hectares of contaminated land. In the San Francisco Bay Area, we found that GWR is predicted to impact twice as much land area as inundation from SLR, and 5,282 additional state‐managed sites of contamination may be vulnerable to inundation from GWR in a 1.0 m SLR scenario. Increases of only a few centimeters of elevation can mobilize soil contaminants, alter flow directions in a heterogeneous urban environment with underground pipes and utility trenches, and result in new exposure pathways. Pumping for flood protection will elevate the saltwater interface, changing groundwater salinity and mobilizing metals in soil. Socially vulnerable communities are disproportionately exposed to this risk at both the national scale and in a regional comparison with the San Francisco Bay Area.

Abstract Talc‐rich rocks are common in exhumed subduction zone terranes and may explain geophysical observations of the subduction zone interface, particularly beneath Guerrero, Mexico, where the Cocos plate subducts horizontally beneath North America and episodic tremor and slow slip (ETS) occurs. We present petrologic models exploring (a) the degree of silica metasomatism required to produce talc in serpentinized peridotites at the pressure‐temperature conditions of the plate interface beneath Guerrero and (b) the amount of silica‐bearing water produced by rocks from the subducting Cocos plate and the location of fluid pulses. We estimate the volumes of talc produced by the advection of silica‐rich fluids into serpentinized peridotites at the plate interface over the history of the flat‐slab system. In the ETS‐hosting region, serpentinites must achieve ∼43 wt. % SiO2 to stabilize talc, but minor additions of silica beyond this produce large volumes of talc. Our models of Cocos plate dehydration predict that water flux into the interface averages 3.9 × 104 kg m−2 Myr−1 but suggest that only where subducting basalts undergo major dehydration reactions will sufficient amounts of silica‐rich fluids be produced to drive significant metasomatism. We suggest that talc produced by advective transport of aqueous silica alone cannot account for geophysical interpretations of km‐thick zones of talc‐rich rocks beneath Guerrero, although silica‐bearing fluids that migrate along the plate interface may promote broader metasomatism. Regions of predicted talc production do, however, overlap with the spatial occurrence of ETS, consistent with models of slow slip based on the frictional deformation of metasomatic lithologies.

Abstract Background The ketone bodies β‐hydroxybutyrate (BOHB) and acetone are generated as a byproduct of the fat metabolism process. In healthy individuals, ketone body levels are ∼0.1 mM for BOHB and ∼1 part per million for breath acetone (BrAce). These levels can increase dramatically as a consequence of a disease process or when used therapeutically for disease treatment. For example, increased ketone body concentration during weight loss is an indication of elevated fat metabolism. Ketone body measurement is relatively inexpensive and can provide metabolic insights to help guide disease management and optimize weight loss. Methods This review of the literature provides metabolic mechanisms and typical concentration ranges of ketone bodies, which can give new insights into these conditions and rationale for measuring ketone bodies. Results Diseases such as heart failure and ketoacidosis can affect caloric intake and macronutrient management, which can elevate BOHB 30‐fold and BrAce 1000‐fold. Other diseases associated with obesity, such as brain dysfunction, cancer, and diabetes, may cause dysfunction because of an inability to use glucose, excessive reliance on glucose, or poor insulin signaling. Elevating ketone body concentrations (e.g., nutritional ketosis) may improve these conditions by forcing utilization of ketone bodies, in place of glucose, for fuel. During weight loss, monitoring ketone body concentration can demonstrate program compliance and can be used to optimize the weight‐loss plan. Conclusions The role of ketone bodies in states of pathologic and therapeutic ketosis indicates that accurate measurement and monitoring of BOHB or BrAce will likely improve disease management. Bariatric surgery is examined as a case study for monitoring both types of ketosis.

Abstract Background Socioeconomic status (SES) is associated with diagnostic and treatment delays and survival in multiple cancers, but less data exist for anal squamous cell carcinoma (ASCC). This study investigated the association between SES and outcomes for patients undergoing definitive chemoradiation therapy for ASCC. Methods One hundred and eleven patients diagnosed with nonmetastatic ASCC between 2005 and 2018 were retrospectively reviewed. Socioeconomic predictor variables included primary payer, race, income, employment, and partnership status. Outcomes included the tumor‐node (TN) stage at diagnosis, the duration from diagnosis to treatment initiation, relapse‐free survival (RFS), and overall survival (OS). Age, gender, TN stage, and HIV status were analyzed as covariates in survival analysis. Results SES was not associated with the TN stage at diagnosis. SES factors associated with treatment initiation delays were Medicaid payer (P = .016) and single partnership status (P = .016). Compared to privately insured patients, Medicaid patients had lower 2‐year RFS (64.4% vs 93.8%, P = .021) and OS (82.9% vs 93.5%, P = .038). Similarly, relative to patients in the racial majority, racial minority patients had lower 2‐year RFS (53.3% vs 93.5%, P = .001) and OS (73.7% vs 92.6%, P = .008). Race was an independent predictor for both RFS (P = .027) and OS (P = .047). Conclusions These results highlight the impact of social contextual factors on health. Interventions targeted at socioeconomically vulnerable populations are needed to reduce disparities in ASCC outcomes.

Abstract In plants, the phenylpropanoid pathway is responsible for the synthesis of a diverse array of secondary metabolites that include lignin monomers, flavonoids, and coumarins, many of which are essential for plant structure, biomass recalcitrance, stress defense, and nutritional quality. Our previous studies have demonstrated that Populus trichocarpa PtrEPSP‐TF, an isoform of 5‐enolpyruvylshikimate 3‐phosphate (EPSP) synthase, has transcriptional activity and regulates phenylpropanoid biosynthesis in Populus. In this study, we report the identification of single nucleotide polymorphism (SNP) of PtrEPSP‐TF that defines its functionality. Populus natural variants carrying this SNP were shown to have reduced lignin content. Here, we demonstrated that the SNP‐induced substitution of 142nd amino acid (PtrEPSP‐TFD142E) dramatically impairs the DNA‐binding and transcriptional activity of PtrEPSP‐TF. When introduced to a monocot species rice (Oryza sativa) in which an EPSP synthase isoform with the DNA‐binding helix‐turn‐helix (HTH) motif is absent, the PtrEPSP‐TF, but not PtrEPSP‐TFD142E, activated genes in the phenylpropanoid pathway. More importantly, heterologous expression of PtrEPSP‐TF uncovered five new transcriptional regulators of phenylpropanoid biosynthesis in rice. Collectively, this study identifies the key amino acid required for PtrEPSP‐TF functionality and provides a strategy to uncover new transcriptional regulators in phenylpropanoid biosynthesis.