Head Contact and Suspected Concussion Rates in Youth Basketball: Time to Target Head Contact Penalties for Prevention.

OBJECTIVE: To compare game events, head contact (HC) rates, and suspected concussion incidence rates (IRs) in boys' and girls' youth basketball. DESIGN: Cross-sectional. SETTING: Canadian club basketball teams (U16-U18). PARTICIPANTS: Players from 24 boys' and 24 girls' Canadian club basketball teams during the 2022 season. ASSESSMENT OF RISK FACTORS: Recorded games were analyzed using Dartfish video analysis software to compare sexes. MAIN OUTCOME MEASURES: Poisson regression analyses were used to estimate HCs [direct (HC1) and indirect (HC2)], suspected concussion IRs, and IR ratios (IRRs). Game event, court location, and HC1 fouls were reported. RESULTS: Division 1 HC rates did not differ between boys (n = 238; IR = 0.50/10 player-minutes; 95% confidence interval [CI], 0.43-0.56) and girls (n = 220; IR = 0.46/10 player-minutes; 95% CI, 0.40-0.52). Division 2 boys experienced 252 HCs (IR = 0.53/10 player-minutes; 95% CI, 0.46-0.59); girls experienced 192 HCs (IR = 0.40/10 player-minutes; 95% CI, 0.35-0.46). Division 2 boys sustained higher HC1 IRs compared with Division 2 girls (IRR = 1.42; 95% CI, 1.15-1.74). Head contacts, rates did not differ between boys and girls in either Division. Suspected concussion IRs were not significantly different for boys and girls in each Division. Head contacts occurred mostly in the key for boys and girls in each Division. Despite illegality, HC1 penalization ranged from 3.9% to 19.7%. Head contact mechanisms varied across Divisions and sexes. CONCLUSIONS: Despite current safety measures, both HCs and suspected concussions occur in boys' and girls' basketball. Despite the illegality and potential danger associated with HC, only a small proportion of direct HCs were penalized and therefore targeting greater enforcement of these contacts may be a promising prevention target.

Growth hormone treatment for neurologic symptoms of post-acute sequelae of COVID-19.

Following SARS-CoV-2 infection, some patients develop lingering neurologic symptoms of post-acute sequelae of COVID-19 (PASC) that commonly include fatigue and "brain fog." PASC symptoms are also linked with reduced growth hormone (GH) secretion, but GH treatment has not been tested to relieve symptoms. We enrolled 13 adults with neurologic PASC symptoms and peak stimulated GH secretion less than 10 ng/mL (glucagon stimulation) in a pilot study to receive 9 months of daily GH injections and an additional 3 months of off-treatment assessment. We compared peak stimulated GH secretion at baseline and 12 months and assessed measures of cognition, metabolism, body composition, and physical performance over the first 6 months of treatment. Patient-reported outcomes of fatigue, quality of life, sleep, and mood were recorded at baseline and compared with timepoints at 6, 9, and 12 months. GH treatment was associated with significantly improved scores for Brief Fatigue Inventory, Multidimensional Fatigue Symptom Inventory, Quality of Life Assessment of Growth Hormone Deficiency in Adults, Profile of Mood States, and Beck Depression Inventory-II, with no significant change in Pittsburgh Sleep Quality Index. Six months of adjunct GH treatment was not associated with significant changes in cognition, body composition, resting energy expenditure, or physical performance. Peak stimulated GH secretion was not altered at 12 months following 9 months of GH treatment. GH treatment significantly improved neurologic symptoms in PASC patients but cognition, sleep, and physical performance were not significantly altered.

Deciphering HIV-associated inflammation: microbiome's influence and experimental insights.

PURPOSE OF REVIEW: To review novel experimental approaches for studying host:microbe interactions and their role in intestinal and systemic inflammation in people living with HIV (PLWH). RECENT FINDINGS: Inflammation in PLWH is impacted by interactions between the microbiome, the intestinal epithelium, and immune cells. This complex interplay is not fully understood and requires a variety of analytical techniques to study. Using a multiomic systems biology approach provides hypothesis generating data on host:microbe interactions that can be used to guide further investigation. The direct interactions between host cells and microbes can be elucidated using peripheral blood mononuclear cells (PBMCs), lamina propria mononuclear cells (LPMC's) or human intestinal organoids (HIO). Additionally, the broader relationship between the host and the microbiome can be explored using animal models such as nonhuman primates and germ-free and double humanized mice. SUMMARY: To explore complex host:microbe relationships, hypotheses are generated and investigations are guided by multiomic data, while causal components are identified using in-vitro and in-vivo assays.

Acid-catalyzed transformation of orange waste into furfural: the effect of pectin degree of esterification.

The transformation of biomasses from agro-industrial waste can significantly impact the production of green chemicals from sustainable resources. Pectin is a biopolymer present in lignocellulosic biomass as Orange Peel Waste (OPW) and has possibilities for making platform compounds such as furfural for sustainable chemistry. In this work, we studied the transformation to furfural of OPW, pectins, and D-galacturonic acid (D-GalA), which is the main component (65 wt%) of pectin. We analyzed pectins with different degrees of esterification (45, 60 and 95 DE) in a one-pot hydrolysis reaction system and studied the differences in depolymerization and dehydration of the carbohydrates. The results show that the production of furfural decreases as the DE value increases. Specifically, low DE values favor the formation of furfural since the decarboxylation reaction is favored over deesterification. Interestingly, the furfural concentration is dependent upon the polysaccharide composition of pentoses and uronic acid. The obtained concentrations of furfural (13 and 14 mmol/L), D-xylose (6.2 and 10 mmol/L), and L-arabinose (2.5 and 2.7 mmol/L) remained the same when the galacturonic acid was fed either as a polymer or a monomer under the same reaction conditions (0.01 M SA, 90 min and 433 K). OPW is proposed as a feedstock in a biorefinery, in which on a per kg OPW dry basis, 90 g of pectin and 15 g of furfural were produced in the most favorable case. We conclude that the co-production of pectin and furfural from OPW is economically feasible.

Stress phenotyping analysis leveraging autofluorescence image sequences with machine learning.

Background: Autofluorescence-based imaging has the potential to non-destructively characterize the biochemical and physiological properties of plants regulated by genotypes using optical properties of the tissue. A comparative study of stress tolerant and stress susceptible genotypes of Brassica rapa with respect to newly introduced stress-based phenotypes using machine learning techniques will contribute to the significant advancement of autofluorescence-based plant phenotyping research. Methods: Autofluorescence spectral images have been used to design a stress detection classifier with two classes, stressed and non-stressed, using machine learning algorithms. The benchmark dataset consisted of time-series image sequences from three Brassica rapa genotypes (CC, R500, and VT), extreme in their morphological and physiological traits captured at the high-throughput plant phenotyping facility at the University of Nebraska-Lincoln, USA. We developed a set of machine learning-based classification models to detect the percentage of stressed tissue derived from plant images and identified the best classifier. From the analysis of the autofluorescence images, two novel stress-based image phenotypes were computed to determine the temporal variation in stressed tissue under progressive drought across different genotypes, i.e., the average percentage stress and the moving average percentage stress. Results: The study demonstrated that both the computed phenotypes consistently discriminated against stressed versus non-stressed tissue, with oilseed type (R500) being less prone to drought stress relative to the other two Brassica rapa genotypes (CC and VT). Conclusion: Autofluorescence signals from the 365/400 nm excitation/emission combination were able to segregate genotypic variation during a progressive drought treatment under a controlled greenhouse environment, allowing for the exploration of other meaningful phenotypes using autofluorescence image sequences with significance in the context of plant science.

The Lung Cancer Prediction Model "Stress Test": Assessment of Models' Performance in a High-Risk Prospective Pulmonary Nodule Cohort.

BACKGROUND: Pulmonary nodules represent a growing health care burden because of delayed diagnosis of malignant lesions and overtesting for benign processes. Clinical prediction models were developed to inform physician assessment of pretest probability of nodule malignancy but have not been validated in a high-risk cohort of nodules for which biopsy was ultimately performed. RESEARCH QUESTION: Do guideline-recommended prediction models sufficiently discriminate between benign and malignant nodules when applied to cases referred for biopsy by navigational bronchoscopy? STUDY DESIGN AND METHODS: We assembled a prospective cohort of 322 indeterminate pulmonary nodules in 282 patients referred to a tertiary medical center for diagnostic navigational bronchoscopy between 2017 and 2019. We calculated the probability of malignancy for each nodule using the Brock model, Mayo Clinic model, and Veterans Affairs (VA) model. On a subset of 168 patients who also had PET-CT scans before biopsy, we also calculated the probability of malignancy using the Herder model. The performance of the models was evaluated by calculating the area under the receiver operating characteristic curves (AUCs) for each model. RESULTS: The study cohort contained 185 malignant and 137 benign nodules (57% prevalence of malignancy). The malignant and benign cohorts were similar in terms of size, with a median longest diameter for benign and malignant nodules of 15 and 16 mm, respectively. The Brock model, Mayo Clinic model, and VA model showed similar performance in the entire cohort (Brock AUC, 0.70; 95% CI, 0.64-0.76; Mayo Clinic AUC, 0.70; 95% CI, 0.64-0.76; VA AUC, 0.67; 95% CI, 0.62-0.74). For 168 nodules with available PET-CT scans, the Herder model had an AUC of 0.77 (95% CI, 0.68-0.85). INTERPRETATION: Currently available clinical models provide insufficient discrimination between benign and malignant nodules in the common clinical scenario in which a patient is being referred for biopsy, especially when PET-CT scan information is not available.

Low-loss and polarization insensitive 32 × 4 optical switch for ROADM applications.

Integrated switches play a crucial role in the development of reconfigurable optical add-drop multiplexers (ROADMs) that have greater flexibility and compactness, ultimately leading to robust single-chip solutions. Despite decades of research on switches with various structures and platforms, achieving a balance between dense integration, low insertion loss (IL), and polarization-dependent loss (PDL) remains a significant challenge. In this paper, we propose and demonstrate a 32 × 4 optical switch using high-index doped silica glass (HDSG) for ROADM applications. This switch is designed to route any of the 32 inputs to the express ports or drop any channels from 32 inputs to the target 4 drop ports or add any of the 4 ports to any of the 32 express channels. The switch comprises 188 Mach-Zehnder Interferometer (MZI) type switch elements, 88 optical vias for the 44 optical bridges, and 618 waveguide-waveguide crossings with three-dimensional (3D) structures. At 1550 nm, the fiber-to-fiber loss for each express channel is below 2 dB, and across the C and L bands, below 3 dB. For each input channel to all 4 drop/add channels at 1550 nm, the loss is less than 3.5 dB and less than 5 dB across the C and L bands. The PDLs for all express and input channels to the 4 drop/add channels are below 0.3 dB over the C band, and the crosstalk is under -50 dB for both the C and L bands.

Dual-polarization RF channelizer based on microcombs.

We report a dual-polarization radio frequency (RF) channelizer based on microcombs. Two high-Q micro-ring resonators (MRRs) with slightly different free spectral ranges (FSRs) are used: one MRR is pumped to yield soliton crystal microcombs ("active"), and the other MRR is used as a "passive" periodic optical filter supporting dual-polarization operation to slice the RF spectrum. With the tailored mismatch between the FSRs of the active and passive MRRs, wideband RF spectra can be channelized into multiple segments featuring digital-compatible bandwidths via the Vernier effect. Due to the use of dual-polarization states, the number of channelized spectral segments, and thus the RF instantaneous bandwidth (with a certain spectral resolution), can be doubled. In our experiments, we used 20 microcomb lines with ∼ 49 GHz FSR to achieve 20 channels for each polarization, with high RF spectra slicing resolutions at 144 MHz (TE) and 163 MHz (TM), respectively; achieving an instantaneous RF operation bandwidth of 3.1 GHz (TE) and 2.2 GHz (TM). Our approach paves the path towards monolithically integrated photonic RF receivers (the key components - active and passive MRRs are all fabricated on the same platform) with reduced complexity, size, and unprecedented performance, which is important for wide RF applications with digital-compatible signal detection.

Building CapaCITY/É for sustainable transportation: protocol for an implementation science research program in healthy cities.

INTRODUCTION: Improving sustainable transportation options will help cities tackle growing challenges related to population health, congestion, climate change and inequity. Interventions supporting active transportation face many practical and political hurdles. Implementation science aims to understand how interventions or policies arise, how they can be translated to new contexts or scales and who benefits. Sustainable transportation interventions are complex, and existing implementation science frameworks may not be suitable. To apply and adapt implementation science for healthy cities, we have launched our mixed-methods research programme, CapaCITY/É. We aim to understand how, why and for whom sustainable transportation interventions are successful and when they are not. METHODS AND ANALYSIS: Across nine Canadian municipalities and the State of Victoria (Australia), our research will focus on two types of sustainable transportation interventions: all ages and abilities bicycle networks and motor vehicle speed management interventions. We will (1) document the implementation process and outcomes of both types of sustainable transportation interventions; (2) examine equity, health and mobility impacts of these interventions; (3) advance implementation science by developing a novel sustainable transportation implementation science framework and (4) develop tools for scaling up and scaling out sustainable transportation interventions. Training activities will develop interdisciplinary scholars and practitioners able to work at the nexus of academia and sustainable cities. ETHICS AND DISSEMINATION: This study received approval from the Simon Fraser University Office of Ethics Research (H22-03469). A Knowledge Mobilization Hub will coordinate dissemination of findings via a website; presentations to academic, community organisations and practitioner audiences; and through peer-reviewed articles.

Single-cell dissection of the human motor and prefrontal cortices in ALS and FTLD.

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) share many clinical, pathological, and genetic features, but a detailed understanding of their associated transcriptional alterations across vulnerable cortical cell types is lacking. Here, we report a high-resolution, comparative single-cell molecular atlas of the human primary motor and dorsolateral prefrontal cortices and their transcriptional alterations in sporadic and familial ALS and FTLD. By integrating transcriptional and genetic information, we identify known and previously unidentified vulnerable populations in cortical layer 5 and show that ALS- and FTLD-implicated motor and spindle neurons possess a virtually indistinguishable molecular identity. We implicate potential disease mechanisms affecting these cell types as well as non-neuronal drivers of pathogenesis. Finally, we show that neuron loss in cortical layer 5 tracks more closely with transcriptional identity rather than cellular morphology and extends beyond previously reported vulnerable cell types.

Prevalence of fatigue and cognitive impairment after traumatic brain injury.

BACKGROUND: Following traumatic brain injury (TBI) some patients develop lingering comorbid symptoms of fatigue and cognitive impairment. The mild cognitive impairment self-reported by patients is often not detected with neurocognitive tests making it difficult to determine how common and severe these symptoms are in individuals with a history of TBI. This study was conducted to determine the relative prevalence of fatigue and cognitive impairment in individuals with a history of TBI. METHODS: The Fatigue and Altered Cognition Scale (FACs) digital questionnaire was used to assess self-reported fatigue and cognitive impairment. Adults aged 18-70 were digitally recruited for the online anonymous study. Eligible participants provided online consent, demographic data, information about lifetime TBI history, and completed the 20 item FACs questionnaire. RESULTS: A total of 519 qualifying participants completed the online digital study which included 204 participants with a history of TBI of varied cause and severity and 315 with no history of TBI. FACs Total Score was significantly higher in the TBI group (57.7 ± 22.2) compared to non-TBI (39.5 ± 23.9; p<0.0001) indicating more fatigue and cognitive impairment. When stratified by TBI severity, FACs score was significantly higher for all severity including mild (53.9 ± 21.9, p<0.0001), moderate (54.8 ± 24.4, p<0.0001), and severe (59.7 ± 20.9, p<0.0001) TBI. Correlation analysis indicated that more severe TBI was associated with greater symptom severity (p<0.0001, r = 0.3165). Ancillary analysis also suggested that FACs scores may be elevated in participants with prior COVID-19 infection but no history of TBI. CONCLUSIONS: Adults with a history of even mild TBI report significantly greater fatigue and cognitive impairment than those with no history of TBI, and symptoms are more profound with greater TBI severity.

The altered TBI fecal microbiome is stable and functionally distinct.

Introduction: Patients who suffer a traumatic brain injury (TBI) often experience chronic and sometimes debilitating sequelae. Recent reports have illustrated both acute and long-term dysbiosis of the gastrointestinal microbiome with significant alterations in composition and predicted functional consequences. Methods: Working with participants from past research, metagenomic stability of the TBI- associated fecal microbiome (FMB) was evaluated by custom qPCR array comparing a fecal sample from 2015 to one collected in 2020. Metatranscriptomics identified differently expressed bacterial genes and biochemical pathways in the TBI FMB. Microbiota that contributed the largest RNA amounts identified a set of core bacteria most responsible for functional consequences of the TBI FMB. Results: A remarkably stable FMB metagenome with significant similarity (two-tail Spearman nonparametric correlation p < 0.001) was observed between 2015 and 2020 fecal samples from subjects with TBI. Comparing the 2020 TBI FMB metagenome to FMBs from healthy controls confirmed and extended the dysbiotic genera and species. Abundance differences between average TBI and healthy FMBs revealed Bacteroides caccae, B. uniformis, Blautia spp., Collinsella spp., Dialister spp., and Ordoribacter spp. were significantly different. Functionally, the Parabacteroides genus contributed the highest percentage of RNA sequences in control FMBs followed by the Bacteroides genus as the second highest contributor. In the TBI FMB, the Corynebacterium genus contributed the most RNA followed by the Alistipes genus. Corynebacterium and Pseudomonas were distinct in the top 10 contributing genera in the TBI FMB while Parabacteroides and Ruminococcus were unique to the top 10 in controls. Comparing RNA profiles, TBI samples had ∼1.5 fold more expressed genes with almost 700 differently expressed genes (DEGs) mapped to over 100 bacterial species. Bioinformatic analysis associated DEGs with pathways led identifying 311 functions in the average TBI FMB profile and 264 in the controls. By average profile comparison, 30 pathways had significantly different abundance (p < 0.05, t-test) or were detected in >80% of the samples in only one of the cohorts (binary distinction). Discussion: Functional differences between TBI and healthy control FMBs included amino acid metabolism, energy and carbon source usage, fatty acid metabolism, bacterial cell wall component production and nucleic acid synthesis and processing pathways. Together these data shed light on the functional consequences of the dysbiotic TBI FMB decades after injury.

Transcriptomic Analysis of Alzheimer's Disease Pathways in a Pakistani Population.

Background: Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder that is most prevalent in elderly individuals, especially in developed countries, and its prevalence is now increasing in developing countries like Pakistan. Objective: Our goal was to characterize key genes and their levels of expression and related molecular transcriptome networks associated with AD pathogenesis in a pilot case-control study in a Pakistani population. Methods: To obtain the spectrum of molecular networks associated with pathogenesis in AD patients in Pakistan (comparing cases and controls), we used high-throughput qRT-PCR (TaqMan Low-Density Array; n = 33 subjects) coupled with Affymetrix Arrays (n = 8) and Ingenuity Pathway Analysis (IPA) to identify signature genes associated with Amyloid processing and disease pathways. Results: We confirmed 16 differentially expressed AD-related genes, including maximum fold changes observed in CAPNS2 and CAPN1. The global gene expression study observed that 61% and 39% of genes were significantly (p-value 0.05) up- and downregulated, respectively, in AD patients compared to healthy controls. The key pathways include, e.g., Amyloid Processing, Neuroinflammation Signaling, and ErbB4 Signaling. The top-scoring networks in Diseases and Disorders Development were Neurological Disease, Organismal Injury and Abnormalities, and Psychological Disorders. Conclusions: Our pilot study offers a non-invasive and efficient way of investigating gene expression patterns by combining TLDA and global gene expression method in AD patients by utilizing whole blood. This provides valuable insights into the expression status of genes related to Amyloid Processing, which could play potential role in future studies to identify sensitive, early biomarkers of AD in general.

Scalable parallel ultrafast optical random bit generation based on a single chaotic microcomb.

Random bit generators are critical for information security, cryptography, stochastic modeling, and simulations. Speed and scalability are key challenges faced by current physical random bit generation. Herein, we propose a massively parallel scheme for ultrafast random bit generation towards rates of order 100 terabit per second based on a single micro-ring resonator. A modulation-instability-driven chaotic comb in a micro-ring resonator enables the simultaneous generation of hundreds of independent and unbiased random bit streams. A proof-of-concept experiment demonstrates that using our method, random bit streams beyond 2 terabit per second can be successfully generated with only 7 comb lines. This bit rate can be easily enhanced by further increasing the number of comb lines used. Our approach provides a chip-scale solution to random bit generation for secure communication and high-performance computation, and offers superhigh speed and large scalability.

Differential effects of antiretroviral treatment on immunity and gut microbiome composition in people living with HIV in rural versus urban Zimbabwe.

BACKGROUND: The widespread availability of antiretroviral therapy (ART) has dramatically reduced mortality and improved life expectancy for people living with HIV (PLWH). However, even with HIV-1 suppression, chronic immune activation and elevated inflammation persist and have been linked to a pro-inflammatory gut microbiome composition and compromised intestinal barrier integrity. PLWH in urban versus rural areas of sub-Saharan Africa experience differences in environmental factors that may impact the gut microbiome and immune system, in response to ART, yet this has not previously been investigated in these groups. To address this, we measured T cell activation/exhaustion/trafficking markers, plasma inflammatory markers, and fecal microbiome composition in PLWH and healthy participants recruited from an urban clinic in the city of Harare, Zimbabwe, and a district hospital that services surrounding rural villages. PLWH were either ART naïve at baseline and sampled again after 24 weeks of first-line ART and the antibiotic cotrimoxazole or were ART-experienced at both timepoints. RESULTS: Although expected reductions in the inflammatory marker IL-6, T-cell activation, and exhaustion were observed with ART-induced viral suppression, these changes were much more pronounced in the urban versus the rural area. Gut microbiome composition was the most highly altered from healthy controls in ART experienced PLWH, and characterized by both reduced alpha diversity and altered composition. However, gut microbiome composition showed a pronounced relationship with T cell activation and exhaustion in ART-naïve PLWH, suggesting a particularly significant role for the gut microbiome in disease progression in uncontrolled infection. Elevated immune exhaustion after 24 weeks of ART did correlate with both living in the rural location and a more Prevotella-rich/Bacteroides-poor microbiome type, suggesting a potential role for rural-associated microbiome differences or their co-variates in the muted improvements in immune exhaustion in the rural area. CONCLUSION: Successful ART was less effective at reducing gut microbiome-associated inflammation and T cell activation in PLWH in rural versus urban Zimbabwe, suggesting that individuals on ART in rural areas of Zimbabwe may be more vulnerable to co-morbidity related to sustained immune dysfunction in treated infection. Video Abstract.

Compartmentalized ciliation changes of oligodendrocytes in aged mouse optic nerve.

Primary cilia are microtubule-based sensory organelles that project from the apical surface of most mammalian cells, including oligodendrocytes, which are myelinating cells of the central nervous system (CNS) that support critical axonal function. Dysfunction of CNS glia is associated with aging-related white matter diseases and neurodegeneration, and ciliopathies are known to affect CNS white matter. To investigate age-related changes in ciliary profile, we examined ciliary length and frequency in the retinogeniculate pathway, a white matter tract commonly affected by diseases of aging but in which expression of cilia has not been characterized. We found expression of Arl13b, a marker of primary cilia, in a small group of Olig2-positive oligodendrocytes in the optic nerve, optic chiasm, and optic tract in young and aged C57BL/6 wild-type mice. While the ciliary length and ciliated oligodendrocyte cells were constant in young mice in the retinogeniculate pathway, there was a significant increase in ciliary length in the anterior optic nerve as compared to the aged animals. Morphometric analysis confirmed a specific increase in the ciliation rate of CC1+ /Olig2+ oligodendrocytes in aged mice compared with young mice. Thus, the prevalence of primary cilia in oligodendrocytes in the visual pathway and the age-related changes in ciliation suggest that they may play important roles in white matter and age-associated optic neuropathies.

Combining PSII photochemistry and hydraulics improves predictions of photosynthesis and water use from mild to lethal drought.

Rising temperatures and increases in drought negatively impact the efficiency and sustainability of both agricultural and forest ecosystems. Although hydraulic limitations on photosynthesis have been extensively studied, a solid understanding of the links between whole plant hydraulics and photosynthetic processes at the cellular level under changing environmental conditions is still missing, hampering our predictive power for plant mortality. Here, we examined plant hydraulic traits and CO2 assimilation rate under progressive water limitation by implementing Photosystem II (PSII) dynamics with a whole plant process model (TREES). The photosynthetic responses to plant water status were parameterized based on measurements of chlorophyll a fluorescence, gas exchange and water potential for Brassica rapa (R500) grown in a greenhouse under fully watered to lethal drought conditions. The updated model significantly improved predictions of photosynthesis, stomatal conductance and leaf water potential. TREES with PSII knowledge predicted a larger hydraulic safety margin and a decrease in percent loss of conductivity. TREES predicted a slower decrease in leaf water potential, which agreed with measurements. Our results highlight the pressing need for incorporating PSII drought photochemistry into current process models to capture cross-scale plant water dynamics from cell to whole plant level.

Youth Injury Knowledge and Beliefs following Neuromuscular Training Warm-up Implementation in Schools.

Neuromuscular training warm-up programs can reduce injury rates in youth sports, but they often have poor uptake and adherence. Delivering such programs in school physical education classes may provide greater public health benefit, particularly if they promote improved injury knowledge and prevention beliefs amongst students. The purpose of this secondary analysis of a large cluster-randomized controlled trial was to understand how students' (age 11-15 years) knowledge and beliefs change after exposure to an evidence-informed neuromuscular training warm-up program. Six schools delivered the program for a 12-week period in the initial study year (n=566) and two continued to use it in a subsequent "maintenance" year (n=255). Students completed a knowledge and beliefs questionnaire at baseline, 6-week, and 12-week timepoints. Knowledge scores ranged from 7/10 to 8/10 at all timepoints and students generally believed that injuries are preventable. On average, there was less than a one-point change in knowledge between timepoints and there was no change in the median belief scores. There were no meaningful differences between sexes, grades, or previous injury. These findings highlight that knowledge and beliefs are unlikely to change passively through program exposure. More active strategies are needed to improve injury prevention perceptions in this population.

Low growth hormone secretion associated with post-acute sequelae SARS-CoV-2 infection (PASC) neurologic symptoms: A case-control pilot study.

OBJECTIVE: To determine if patients that develop lingering neurologic symptoms of fatigue and "brain fog" after initial recovery from coronavirus disease 2019 (COVID-19) have persistent low growth hormone (GH) secretion as seen in other conditions with similar symptom etiology. DESIGN: In this case-control observational pilot study, patients reporting lingering neurologic post-acute sequelae of SARS-CoV-2 (PASC, n = 10) symptoms at least 6 months after initial infection were compared to patients that recovered from COVID-19 without lingering symptoms (non-PASC, n = 13). We compared basic blood chemistry and select metabolites, lipids, hormones, inflammatory markers, and vitamins between groups. PASC and non-PASC subjects were tested for neurocognition and GH secretion, and given questionnaires to assess symptom severity. PASC subjects were also tested for glucose tolerance and adrenal function. RESULTS: PASC subjects reported significantly worse fatigue, sleep quality, depression, quality of life, and gastrointestinal discomfort compared to non-PASC. Although PASC subjects self-reported poor mental resilience, cognitive testing did not reveal significant differences between groups. Neurologic PASC symptoms were not linked to inflammatory markers or adrenal insufficiency, but were associated with reduced growth hormone secretion. CONCLUSIONS: Neurologic PASC symptoms are associated with gastrointestinal discomfort and persistent disruption of GH secretion following recovery from acute COVID-19. (www. CLINICALTRIALS: gov; NCT04860869).