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This field experiment examined whether the well-documented benefit of spaced over massed training for humans and other animals generalizes to horses. Twenty-nine randomly selected horses (Equus ferus caballus) repeatedly encountered a novel obstacle-crossing task while under saddle. Horses were randomly assigned to the spaced-training condition (2 min work, 2 min rest, 2 min work, 2 min rest) or the massed-training condition (4 min work, 4 min rest). Total training time per session and total rest per session were held constant. Days between sessions (M = 3) were held as consistent as possible given the constraints of conducting research on a working ranch and safety–threatening weather conditions. During each training session, the same hypothesis-naïve rider shaped horses to cross a novel obstacle. Fifteen of 16 horses in the spaced-training condition reached performance criterion (94% success) while only 5 of 13 horses in the massed-training condition reached performance criterion (39% success). Horses in the spaced-training condition also initiated their first obstacle-crossing faster than horses in the massed-training condition and were faster at completing eight crossings than horses in the massed-training condition. Overall, task acquisition was higher for horses undergoing spaced training despite both groups experiencing the same total work and rest time per session. These findings generalize the learning-performance benefit observed in human spaced practice to horses and offer applied benefit to equine training.

BACKGROUND Background: The pandemic has disrupted all aspects of children’s lives and has increased children’s exposure to adversity and traumas known to increase the risk of mental health challenges. Recent studies have reported increased rates of mental health challenges in youth during the pandemic, yet few studies have examined the impact of the pandemic on the mental health of toddlers, preschoolers, and elementary school-age children. The pandemic has also adversely impacted caregiver mental health and other indirect factors, including economic instability, known to increase children’s risk for impairing mental health challenges. OBJECTIVE Objective: This study aimed to characterize the social-emotional challenges of children ages 2 to 12 years old during the pandemic and identify modifiable child, caregiver, and family-related risk factors that contribute to risk and are additional targets for intervention. METHODS Methods: Caregivers (N = 676) of children ages 2-12 completed an online survey in early fall 2021 using standardized screening tools to assess child social-emotional challenges and caregiver anxiety and depression. We used a new 16 scale to assess the impact of the pandemic at the child, caregiver, and family levels. We used hierarchical linear regression and logistic regression to explore the relationship between children’s mental health and caregivers’ mental health. We used path analysis to explore direct and indirect effects of the impact of pandemic stress on child emotional and peer challenges, mediated by caregiver anxiety and depression. RESULTS Results: Eighty-seven percent of the children were ages 2-8 years old (n=588) with 13% (n=88) between 9-12 years old. Caregivers endorsed significant child emotional and peer challenges with 80% (n = 536) of children at risk for clinically-significant emotional challenges and 57% (n = 388) at risk for clinically-significant peer social challenges. Emotional challenges increased with age (r = .20, P CONCLUSIONS Conclusions: The results of our study show that the COVID-19 pandemic is having direct and indirect adverse impacts on the social-emotional health of children ages 2 to 12 years old with impacts on very young children similar to impacts for older children. Only with an integrated, family-focused approach that includes young children will we be able to mitigate the current pediatric mental health crisis. CLINICALTRIAL n/a

BackgroundIndividuals with anorexia nervosa have reported feelings of loneliness, social anhedonia, and interpersonal difficulties. This study sought to clarify the nature of interpersonal relationships in adults with anorexia, which may help improve existing interventions while also facilitating the attainment of something that might compete with the drive for thinness: friendships.MethodsThe present study used a mixed-methods approach to investigate friendship experiences in three groups: anorexia (n = 27), participants with a history of anorexia who are weight restored (n = 20), and healthy controls (n = 24). Thematic analysis was used to isolate the most prevalent themes that emerged from an open-ended interview of experiencing friendships in a subset of participants. Three self-report questionnaires investigating friendship valuation and attachment styles were also administered.Results11 unique themes emerged in the data: social comparison, reciprocity, trust, fear of negative evaluation, perceived skills deficit, logistical barriers, reliability, identity issue, low interest, similarity, and conflict avoidance. Only 17% of those with anorexia reported experiencing friendships as positive, relative to 82% of healthy controls and 52% of weight restored participants. Lastly, on self-report measures, participants with anorexia reported greater reliance on themselves versus others, greater use of care-seeking behaviors, and more fear/anger at the thought of losing an attachment figure (p < .05 in all cases).ConclusionResults suggest that individuals with anorexia have particular challenges which interfere with the formation and maintenance of friendships, such as viewing friendships negatively and struggling with social comparisons in friendships. Assessing and addressing barriers to intimacy may motivate those with anorexia to relinquish dangerous symptoms that maintain the illness.

The claustrum is a functionally and structurally complex brain region, whose very spatial extent remains debated. Histochemical-based approaches typically treat the claustrum as a relatively narrow anatomical region that primarily projects to the neocortex, whereas circuit-based approaches can suggest a broader claustrum region containing projections to the neocortex and other regions. Here, in the mouse, we took a bottom-up and cell-type-specific approach to complement and possibly unite these seemingly disparate conclusions. Using single-cell RNA-sequencing, we found that the claustrum comprises two excitatory neuron subtypes that are differentiable from the surrounding cortex. Multicolor retrograde tracing in conjunction with 12-channel multiplexed in situ hybridization revealed a core-shell spatial arrangement of these subtypes, as well as differential downstream targets. Thus, the claustrum comprises excitatory neuron subtypes with distinct molecular and projection properties, whose spatial patterns reflect the narrower and broader claustral extents debated in previous research. This subtype-specific heterogeneity likely shapes the functional complexity of the claustrum.

OBJECTIVE: Individuals with a gastrointestinal (GI) disorder often alter their diet to manage GI symptoms, adding complexity to understanding the diverse motivations contributing to food avoidance/restriction. When a GI disorder is present, the DSM-5 states that Avoidant/Restrictive Food Intake Disorder (ARFID) can be diagnosed only when eating disturbance exceeds that expected. There is limited guidance to make this determination. This study attempts to address this gap by characterizing the presentation of ARFID in adults with and without a self-reported GI disorder. METHOD: Participants were 2,610 adults ages 18–44 who self-identified as “picky eaters.” Participants reported on motivations for food avoidance, affective experiences towards food, and perceived impairment. Responses were compared across four groups: GI issues and likely ARFID (L-ARFID/GI), L-ARFID-only, GI-only, and No-ARFID/No-GI. RESULTS: Groups with a GI disorder (L-ARFID/GI, GI-only) reported more fear of aversive consequences of eating than those without a GI disorder, while groups with L-ARFID (L-ARFID, L-ARFID/GI) evidenced significantly greater sensory aversion to food and indifference to food or eating, negative emotional reactions to food and overall disgust sensitivity, and eating related impairment. DISCUSSION: Consideration of the interplay of a GI disorder with ARFID can add precision to case conceptualization. Food avoidance may be attempts to manage fears of aversive consequences that are augmented by a history of GI symptoms, while sensory aversions and negative emotional reactions towards foods may be more elevated in ARFID. These findings emphasize the need to consider an ARFID diagnosis in patients with GI disorders to optimize care.

Summary: Animals can store information about experiences by activating specific neuronal populations, and subsequent reactivation of these neural ensembles can lead to recall of salient experiences. In the hippocampus, granule cells of the dentate gyrus participate in such memory engrams; however, whether there is an underlying logic to granule cell participation has not been examined. Here, we find that a range of novel experiences preferentially activates granule cells of the suprapyramidal blade relative to the infrapyramidal blade. Motivated by this, we identify a suprapyramidal-blade-enriched population of granule cells with distinct spatial, morphological, physiological, and developmental properties. Via transcriptomics, we map these traits onto a sparse and discrete granule cell subtype that is recruited at a 10-fold greater frequency than expected by subtype prevalence, constituting the majority of all recruited granule cells. Thus, in behaviors known to involve hippocampal-dependent memory formation, a rare and spatially localized subtype dominates overall granule cell recruitment. : Erwin et al. identify a sparse subtype of mature granule cell, spatially localized within the dentate gyrus, which dominates overall granule cell activity across a range of behavioral paradigms. Thus, subtype-specific heterogeneity exists and predicts cellular recruitment at the first stage of hippocampal processing. Keywords: dentate gyrus, granule cell, single-cell RNA-seq, transcriptomics, memory, cell type, hippocampus

Background Epidermal Growth Factor (EGF) reduces necrotizing enterocolitis (NEC). However, its high cost virtually prohibits clinical use. To reduce cost, soybean expressing human EGF was developed. Here we report effectiveness of soybean-derived EGF in experimental NEC. Methods Newborn rats were subjected to the NEC-inducing regimen of formula feeding and hypoxia. Formula was supplemented with extract from EGF-expressing or empty soybeans. NEC pathology was determined microscopically. Localization of tight junction proteins JAM-A and ZO-1 was examined by immunofluorescence and levels of mucosal COX-2 and iNOS mRNAs by real time PCR. Results Soybean extract amounts corresponding to 150μg/kg/day EGF caused considerable mortality, whereas those corresponding to 75μg/kg/day EGF were well tolerated. There was no significant difference in NEC scores between animals fed plain formula and formula supplemented with empty soybean extract. Soybean-EGF-supplemented formula at 75μg/kg/day EGF significantly decreased NEC, attenuated dissociation of JAM-A and ZO-1 proteins from tight junctions, and reduced intestinal expression of COX-2 and iNOS mRNAs. Conclusion Supplementation with soybean-expressed EGF significantly decreased NEC in the rat model. Soybean-expressed EGF may provide an economical solution for EGF administration and prophylaxis of clinical NEC.

Plasmonic enhancement in organic photovoltaics has been extensively studied in the past decade. However, the reported improvements in power conversion efficiency (PCE) are highly inconsistent due to a poor understanding of the limitations of how plasmonics affect charge generation and transport in solar cells. In this work, we address these long-standing uncharted questions as to when plasmonic enhancements are useful and when they are not. We do this with a model system consisting of poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b?]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)]:[6,6]-phenyl C61 butyric acid methyl ester PCDTBT polymer active layer with silver nanostructures embedded in the poly(3,4-ethylenedioxythiophene):polystyrene PEDOT:PSS sulfonate hole-transport layer. We demonstrate that: (a) plasmonic enhancements are most pronounced when the charge carrier mobilities of the donor and acceptor materials are unbalanced; (b) the introduction of plasmonic nanostructures in devices with balanced charge transport usually results in a decrease in efficiency; (c) plasmonic enhancement is highly shape-dependent; (d) for devices with asymmetric mobilities, as long as the species with low mobility is extracted at the contact where light is incident, device efficiency will be boosted; and (e) increase in light absorption in the active layer has minimal impact on PCE; the efficiency is primarily driven by exciton generation and charge collection efficiency. The findings of our work provide a generalized framework to guide researchers as to when plasmonic effects could be helpful to a device and when they could degrade performance.

Perovskite solar cells (PSCs) have improved at an unprecedented rate, reaching over 22% power conversion efficiency in less than a decade, and have generated a wealth of high impact work in the literature studying the properties of these unique materials. While the highest performance and best progress have been observed with methylammonium lead triiodide perovskites, their low tolerance to moisture and rapid degradation when exposed to UV light and high temperatures have posed a major setback to their commercialization. Recently, mixed halide hybrid perovskites (MHHPs) where I− is substituted with Br− and Cl− have driven a paradigm shift in PSCs, synergistically combining high performance with high ambient stability. In this comprehensive review, we summarize the progress made in the past 5 years in methylammonium-based organic–inorganic MHHPs and cesium-based all inorganic MHHPs. We discuss the fabrication approaches for halide substitution and the resulting crystal structure, long-term stability and durability, and device performance. Unique from other reviews, we focus this review on the optical properties of MHHPs, including light-induced phase segregation and alterations in the optical band gap and photoluminescence with halide substitution. We also summarize trends in carrier dynamics, including carrier thermalization, recombination, and charge transfer probed with time-resolved optical spectroscopies. Furthermore, we provide a short overview on mixed cation hybrid perovskites, where methylammonium is substituted with formamidinium/cesium or Pb is substituted with less toxic and benign metals to improve both the stability and the environmental impact of PSCs. We discuss the optical characteristics of mixed cation perovskites and approaches to lower nonradiative recombination with cation substitution. We conclude this review with a discussion on innovative future directions that will propel research on MHHPs as a game changer in perovskite-based optoelectronics.

Summary We develop roadmaps to transform the all-purpose energy infrastructures (electricity, transportation, heating/cooling, industry, agriculture/forestry/fishing) of 139 countries to ones powered by wind, water, and sunlight (WWS). The roadmaps envision 80% conversion by 2030 and 100% by 2050. WWS not only replaces business-as-usual (BAU) power, but also reduces it ∼42.5% because the work: energy ratio of WWS electricity exceeds that of combustion (23.0%), WWS requires no mining, transporting, or processing of fuels (12.6%), and WWS end-use efficiency is assumed to exceed that of BAU (6.9%). Converting may create ∼24.3 million more permanent, full-time jobs than jobs lost. It may avoid ∼4.6 million/year premature air-pollution deaths today and ∼3.5 million/year in 2050; ∼$22.8 trillion/year (12.7 ¢/kWh-BAU-all-energy) in 2050 air-pollution costs; and ∼$28.5 trillion/year (15.8 ¢/kWh-BAU-all-energy) in 2050 climate costs. Transitioning should also stabilize energy prices because fuel costs are zero, reduce power disruption and increase access to energy by decentralizing power, and avoid 1.5°C global warming.

The self-assembly of colloidal nanocrystals into ordered architectures has attracted significant interest enabling innovative methods of manipulating physicochemical properties for targeted applications. This study reports the self-assembly of CsPbBr3 perovskite nanocrystals (NCs) in one-dimensional (1D) superlattice chains mediated by ligand–solvent interactions. CsPbBr3 NCs synthesized at ≥170 °C and purified in a nonpolar solvent, hexane, self-assembled into 1D chains, whereas those purified in polar solvents, including toluene and ethyl acetate, were disordered or formed short-range two-dimensional (2D) assemblies. The NCs assembled into 1D chains showed red shifts in both the absorbance and photoluminescence spectra relative to those of disordered NCs purified in a 50/50 hexane/ethyl acetate mixture. Microscopy and X-ray diffraction results confirmed the formation of polymeric nanostrands in hexane followed by organization of the NCs into 1D chains along the nanostrands. Our results suggest that exce...

Background A significant number of children with short bowel syndrome experience intestinal failure-associated liver disease. We recently demonstrated accelerated hepatic steatosis after 50% small bowel resection (SBR) in mice. Since SBR is associated with alterations in the gut microbiome, the purpose of this study was to determine whether TLR4 signaling is critical to the development of resection-associated hepatic steatosis. Methods Male C57BL6 (control) and TLR4-knockout (KO) mice underwent 50% proximal SBR. Liver sections were analyzed to obtain the percent lipid content, and Ileal sections were assessed for morphological adaptation. Intestinal TLR4 mRNA expression was measured at 7 days and 10 weeks. Results Compared to controls, TLR4 KO mice demonstrated similar weight gain and morphological adaptation after SBR. Hepatic steatosis was decreased 32-fold in the absence of TLR4. Intestinal TLR4 mRNA expression was significantly elevated 7 days after SBR. We also found that TLR4 expression in the intestine was 20-fold higher in whole bowel sections compared with isolated enterocytes. Conclusions TLR4 signaling is critical for the development of resection-associated steatosis, but not involved in intestinal adaptation after massive SBR. Further studies are needed to delineate the mechanism for TLR4 signaling in the genesis of resection-associated liver injury. Level of evidence Animal study, not clinical.

Animals can store information about experiences by activating specific neuronal populations, and subsequent reactivation of these neural ensembles can lead to recall of salient experiences. In the hippocampus, granule cells of the dentate gyrus participate in such memory engrams; however, whether there is an underlying logic to granule cell participation has not been examined. Here, we found that a broad range of novel experiences preferentially activates granule cells of the suprapyramidal blade relative to the infrapyramidal blade. Motivated by this, we identified a suprapyramidal-blade-enriched population of granule cells with distinct spatial, morphological, physiological, and developmental properties. Via transcriptomics, we mapped these traits onto a sparse and discrete granule cell subtype that was recruited at a ten-fold greater frequency than expected by subtype prevalence, constituting the majority of all recruited granule cells. Thus, a rare and spatially localized granule cell subtype is intrinsically predisposed to activation during hippocampal memory formation.

We present a measurement of B(π0→e+e-γ)/B(π0→γγ), the Dalitz branching ratio, using data taken in 1999 by the E832 KTeV experiment at Fermi National Accelerator Laboratory. We use neutral pions from fully reconstructed KL decays in flight; the measurement is based on ∼60 thousand KL→π0π0π0→γγγγe+e-γ decays. We normalize to KL→π0π0π0→6γ decays. We find B(π0→e+e-γ)/B(π0→γγ) (me+e->15 MeV/c2)=[3.920±0.016(stat)±0.036(syst)]×10-3. Using the Mikaelian and Smith prediction for the e+e- mass spectrum, we correct the result to the full e+e- mass range. The corrected result is B(π0→e+e-γ)/B(π0→γγ)=[1.1559±0.0047(stat)±0.0106(syst)]%. This result is consistent with previous measurements, and the uncertainty is a factor of 3 smaller than any previous measurement.

Background Intestinal failure–associated liver disease causes significant mortality in patients with short bowel syndrome. Steatosis, a major component of intestinal failure–associated liver disease has been shown to persist even after weaning from parenteral nutrition. We sought to determine whether steatosis occurs in our murine model of short bowel syndrome and whether steatosis was affected by manipulation of the intestinal microbiome. Methods Male C57BL6 mice underwent 50% small bowel resection and orogastric gavage with vancomycin or vehicle for 10 weeks. DNA was extracted from stool samples then sequenced using 16s rRNA. Liver lipid content was analyzed. Bile acids were measured in liver and stool. Results Compared with unoperated mice, small bowel resection resulted in significant changes in the fecal microbiome and was associated with a >25-fold increase in steatosis. Oral vancomycin profoundly altered the gut microbiome and was associated with a 15-fold reduction in hepatic lipid content after resection. There was a 17-fold reduction in fecal secondary bile acids after vancomycin treatment. Conclusion Massive small bowel resection in mice is associated with development of steatosis and prevented by oral vancomycin. These findings implicate a critical role for gut bacteria in intestinal failure–associated liver disease pathogenesis and illuminate a novel, operative model for future investigation into this important morbidity.

Although isoniazid (INH) has been successful in treating Tuberculosis (TB) since its introduction in 1952, there has been continual reports of drug-associated hepatotoxicity in TB patients. These toxic side effects may reveal more about the recipient of the drug, than the drug itself. A combination of pharmacogenetic and pharmacokinetic studies have identified polymorphisms within enzymes involved in INH metabolism and detoxification. These essential metabolic enzymes include N-acetyltransferase 2, Cytochrome P450 2E1, and glutathione S transferases. Different phenotypes of these enzymes can affect the rate of INH metabolism, resulting in production of hepatotoxic metabolites. This review is intended to elucidate the pharmacokinetics of INH by examining its Administration, Distribution, Metabolism, and Elimination, while suggesting potential alternatives within INH personalized treatment to help reduce hepatotoxicity.

In this work we demonstrate improved light trapping in dye-sensitized solar cells (DSSCs) with hybrid bimetallic gold core/silver shell nanostructures. Silica-coated bimetallic nanostructures (Au/Ag/SiO2 NSs) integrated in the active layer of DSSCs resulted in 7.51% power conversion efficiency relative to 5.97% for reference DSSCs, giving rise to 26% enhancement in device performance. DSSC efficiencies were governed by the particle density of Au/Ag/SiO2 NSs with best performing devices utilizing only 0.44 wt % of nanostructures. We performed transient absorption spectroscopy of DSSCs with variable concentrations of Au/Ag/SiO2 NSs and observed an increase in amplitude and decrease in lifetime with increasing particle density relative to reference. We attributed this trend to plasmon resonant energy transfer and population of the singlet excited states of the sensitizer molecules at the optimum concentration of NSs promoting enhanced exciton generation and rapid charge transfer into TiO2.

In this work, we investigate the effects of grain structure and bromide content on charge transport in methylammonium lead iodide/bromide (MAPb(I1−xBrx)3) perovskites by examining the steady-state (ss-PL) and time-resolved (tr-PL) photoluminescence of planar films with varying grain size and bromide content. We controlled the perovskite grain structure via solvent engineering with N,N-dimethylformamide (DMF) or dimethyl sulfoxide : γ-butyrolactone (DMSO : GBL), and the resultant grain morphology was independent of Br doping between 0–33%. Carrier lifetimes ranged from 29–52 ns with increasing Br content for DMF-produced perovskite films, and from 2–9 ns for films obtained with DMSO : GBL. Analysis of XRD and photoluminescence data suggests this order-of-magnitude difference in lifetimes is attributable to the nature of iodide-rich recombination nuclei within the bulk perovskite. By modulating the precursor solvent and Br composition, the influence of low-bandgap recombination nuclei can be minimized to enhance charge transport and lengthen the carrier lifetime in mixed-halide perovskite films.

Plasmon resonances in metal nanostructures have been extensively harnessed for light trapping in mesoporous solar cells (MSCs), including dye-sensitized solar cells (DSSCs) and recently in perovskite solar cells (PSCs). By altering the geometry, dimension, and composition of metal nanostructures, their optical characteristics can be tuned to either overlap with the sensitizer absorption and enhance light harvesting, or absorb light at a wavelength complementary to the sensitizer enabling broadband solar light capture in MSCs. In this comprehensive review, we discuss the mechanisms of plasmonic enhancement in MSCs including far-field coupling of scattered light, near-field coupling of localized electromagnetic fields, hot electron transfer, and plasmon resonant energy transfer. We then summarize the progress in plasmon enhanced DSSCs in the past decade and decouple the impact of metal nanostructure shape, size, composition, and surface coatings on the overall efficiency. Further, we also discuss the recent advances in plasmon-enhanced perovskite solar cells. Distinct from other published reviews, we discuss the significance of femtosecond spectroscopies to probe the fundamental underpinnings of plasmon enhanced phenomena and understand the mechanisms that give rise to energy transfer between metal nanoparticles and solar materials. The review concludes with a discussion on the challenges in plasmonic device fabrication, and the promise of low-loss semiconductor nanocrystals for plasmonic enhancement in MSCs that facilitate light capture in the infrared.