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Night-migratory songbirds are remarkably proficient navigators1. Flying alone and often over great distances, they use various directional cues including, crucially, a light-dependent magnetic compass2,3. The mechanism of this compass has been suggested to rely on the quantum spin dynamics of photoinduced radical pairs in cryptochrome flavoproteins located in the retinas of the birds4-7. Here we show that the photochemistry of cryptochrome 4 (CRY4) from the night-migratory European robin (Erithacus rubecula) is magnetically sensitive in vitro, and more so than CRY4 from two non-migratory bird species, chicken (Gallus gallus) and pigeon (Columba livia). Site-specific mutations of ErCRY4 reveal the roles of four successive flavin-tryptophan radical pairs in generating magnetic field effects and in stabilizing potential signalling states in a way that could enable sensing and signalling functions to be independently optimized in night-migratory birds.
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Migração Animal , Criptocromos/genética , Campos Magnéticos , Aves Canoras , Animais , Proteínas Aviárias/genética , Galinhas , Columbidae , RetinaRESUMO
Increasing human populations around the global coastline have caused extensive loss, degradation and fragmentation of coastal ecosystems, threatening the delivery of important ecosystem services1. As a result, alarming losses of mangrove, coral reef, seagrass, kelp forest and coastal marsh ecosystems have occurred1-6. However, owing to the difficulty of mapping intertidal areas globally, the distribution and status of tidal flats-one of the most extensive coastal ecosystems-remain unknown7. Here we present an analysis of over 700,000 satellite images that maps the global extent of and change in tidal flats over the course of 33 years (1984-2016). We find that tidal flats, defined as sand, rock or mud flats that undergo regular tidal inundation7, occupy at least 127,921 km2 (124,286-131,821 km2, 95% confidence interval). About 70% of the global extent of tidal flats is found in three continents (Asia (44% of total), North America (15.5% of total) and South America (11% of total)), with 49.2% being concentrated in just eight countries (Indonesia, China, Australia, the United States, Canada, India, Brazil and Myanmar). For regions with sufficient data to develop a consistent multi-decadal time series-which included East Asia, the Middle East and North America-we estimate that 16.02% (15.62-16.47%, 95% confidence interval) of tidal flats were lost between 1984 and 2016. Extensive degradation from coastal development1, reduced sediment delivery from major rivers8,9, sinking of riverine deltas8,10, increased coastal erosion and sea-level rise11 signal a continuing negative trajectory for tidal flat ecosystems around the world. Our high-spatial-resolution dataset delivers global maps of tidal flats, which substantially advances our understanding of the distribution, trajectory and status of these poorly known coastal ecosystems.
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Ecossistema , Mapeamento Geográfico , Sedimentos Geológicos/análise , Ondas de Maré , Ásia , América do Norte , Reprodutibilidade dos Testes , Imagens de Satélites , América do SulRESUMO
The outstanding mechanical and chemical properties of dental enamel emerge from its complex hierarchical architecture. An accurate, detailed multiscale model of the structure and composition of enamel is important for understanding lesion formation in tooth decay (dental caries), enamel development (amelogenesis) and associated pathologies (e.g., amelogenesis imperfecta or molar hypomineralization), and minimally invasive dentistry. Although features at length scales smaller than 100 nm (individual crystallites) and greater than 50 µm (multiple rods) are well understood, competing field of view and sampling considerations have hindered exploration of mesoscale features, i.e., at the level of single enamel rods and the interrod enamel (1 to 10 µm). Here, we combine synchrotron X-ray diffraction at submicrometer resolution, analysis of crystallite orientation distribution, and unsupervised machine learning to show that crystallographic parameters differ between rod head and rod tail/interrod enamel. This variation strongly suggests that crystallites in different microarchitectural domains also differ in their composition. Thus, we use a dilute linear model to predict the concentrations of minority ions in hydroxylapatite (Mg2+ and CO32-/Na+) that plausibly explain the observed lattice parameter variations. While differences within samples are highly significant and of similar magnitude, absolute values and the sign of the effect for some crystallographic parameters show interindividual variation that warrants further investigation. By revealing additional complexity at the rod/interrod level of human enamel and leaving open the possibility of modulation across larger length scales, these results inform future investigations into mechanisms governing amelogenesis and introduce another feature to consider when modeling the mechanical and chemical performance of enamel.
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Amelogênese Imperfeita , Cárie Dentária , Humanos , Cristalografia , Amelogênese , Esmalte DentárioRESUMO
Cell-free hemoglobin (CFH) is elevated in the airspace of patients with acute respiratory distress syndrome (ARDS) and is sufficient to cause acute lung injury in a murine model. However, the pathways through which CFH causes lung injury are not well understood. Toll-like receptor 4 (TLR4) is a mediator of inflammation after detection of damage- and pathogen-associated molecular patterns. We hypothesized that TLR4 signaling mediates the proinflammatory effects of CFH in the airspace. After intratracheal CFH, BALBc mice deficient in TLR4 had reduced inflammatory cell influx into the airspace [bronchoalveolar lavage (BAL) cell counts, median TLR4 knockout (KO): 0.8 × 104/mL [IQR 0.4-1.2 × 104/mL], wild-type (WT): 3.0 × 104/mL [2.2-4.0 × 104/mL], P < 0.001] and attenuated lung permeability (BAL protein, TLR4KO: 289 µg/mL [236-320], WT: 488 µg/mL [422-536], P < 0.001). These mice also had attenuated production of interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α in the airspace. C57Bl/6 mice lacking TLR4 on myeloid cells only (LysM.Cre+/-TLR4fl/fl) had reduced cytokine production in the airspace after CFH, without attenuation of lung permeability. In vitro studies confirm that WT primary murine alveolar macrophages exposed to CFH (0.01-1 mg/mL) had dose-dependent increases in IL-6, IL-1 ß, CXC motif chemokine ligand 1 (CXCL-1), TNF-α, and IL-10 (P < 0.001). Murine MH-S alveolar-like macrophages show TLR4-dependent expression of IL-1ß, IL-6, and CXCL-1 in response to CFH. Primary alveolar macrophages from mice lacking TLR4 adaptor proteins myeloid differentiation primary response 88 (MyD88) or TIR-domain-containing adapter-inducing interferon-ß (TRIF) revealed that MyD88KO macrophages had 71-96% reduction in CFH-dependent proinflammatory cytokine production (P < 0.001), whereas macrophages from TRIFKO mice had variable changes in cytokine responses. These data demonstrate that myeloid TLR4 signaling through MyD88 is a key regulator of airspace inflammation in response to CFH.NEW & NOTEWORTHY Cell-free hemoglobin (CFH) is elevated in the airspace of most patients with acute respiratory distress syndrome and causes severe inflammation. Here, we identify that CFH contributes to macrophage-induced cytokine production via Toll-like receptor 4 (TLR4) and myeloid differentiation primary response 88 (MyD88) signaling. These data increase our knowledge of the mechanisms through which CFH contributes to lung injury and may inform development of targeted therapeutics to attenuate inflammation.
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Lesão Pulmonar Aguda , Síndrome do Desconforto Respiratório , Humanos , Camundongos , Animais , Receptor 4 Toll-Like/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Interleucina-6/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Citocinas/metabolismo , Macrófagos/metabolismo , Inflamação/etiologia , Fator de Necrose Tumoral alfa/metabolismo , Lesão Pulmonar Aguda/metabolismo , Hemoglobinas/metabolismo , Síndrome do Desconforto Respiratório/complicações , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
BACKGROUND: Antenatal corticosteroids for women at risk of preterm birth reduce neonatal morbidity and mortality, but there is limited evidence regarding their effects on long-term health. This study assessed cardiovascular outcomes at 50 years after antenatal exposure to corticosteroids. METHODS AND FINDINGS: We assessed the adult offspring of women who participated in the first randomised, double-blind, placebo-controlled trial of antenatal betamethasone for the prevention of neonatal respiratory distress syndrome (RDS) (1969 to 1974). The first 717 mothers received 2 intramuscular injections of 12 mg betamethasone or placebo 24 h apart and the subsequent 398 received 2 injections of 24 mg betamethasone or equivalent volume of placebo. Follow-up included a health questionnaire and consent to access administrative data sources. The co-primary outcomes were the prevalence of cardiovascular risk factors (any of hypertension, hyperlipidaemia, diabetes mellitus, gestational diabetes mellitus, or prediabetes) and age at first major adverse cardiovascular event (MACE) (cardiovascular death, myocardial infarction, coronary revascularisation, stroke, admission for peripheral vascular disease, and admission for heart failure). Analyses were adjusted for gestational age at entry, sex, and clustering. Of 1,218 infants born to 1,115 mothers, we followed up 424 (46% of survivors; 212 [50%] female) at mean (standard deviation) age 49.3 (1.0) years. There were no differences between those exposed to betamethasone or placebo for cardiovascular risk factors (159/229 [69.4%] versus 131/195 [67.2%]; adjusted relative risk 1.02, 95% confidence interval [CI] [0.89, 1.18;]; p = 0.735) or age at first MACE (adjusted hazard ratio 0.58, 95% CI [0.23, 1.49]; p = 0.261). There were also no differences in the components of these composite outcomes or in any of the other secondary outcomes. Key limitations were follow-up rate and lack of in-person assessments. CONCLUSIONS: There is no evidence that antenatal corticosteroids increase the prevalence of cardiovascular risk factors or incidence of cardiovascular events up to 50 years of age. Established benefits of antenatal corticosteroids are not outweighed by an increase in adult cardiovascular disease.
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Nascimento Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido , Lactente , Adulto , Feminino , Recém-Nascido , Humanos , Gravidez , Pessoa de Meia-Idade , Masculino , Betametasona/efeitos adversos , Seguimentos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Nascimento Prematuro/tratamento farmacológico , Corticosteroides , Pulmão , Síndrome do Desconforto Respiratório do Recém-Nascido/tratamento farmacológico , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controleRESUMO
BACKGROUND: The objective of this study was to quantify disparities in cancer treatment delivery between minority-serving hospitals (MSHs) and non-MSHs for breast, prostate, nonsmall cell lung, and colon cancers from 2010 to 2019 and to estimate the impact of improving care at MSHs on national disparities. METHODS: Data from the National Cancer Database (2010-2019) identified patients who were eligible for definitive treatments for the specified cancers. Hospitals in the top decile by minority patient proportion were classified as MSHs. Multivariable logistic regression adjusted for patient and hospital characteristics compared the odds of receiving definitive treatment at MSHs versus non-MSHs. A simulation was used to estimate the increase in patients receiving definitive treatment if MSH care matched the levels of non-MSH care. RESULTS: Of 2,927,191 patients from 1330 hospitals, 9.3% were treated at MSHs. MSHs had significant lower odds of delivering definitive therapy across all cancer types (adjusted odds ratio: breast cancer, 0.83; prostate cancer, 0.69; nonsmall cell lung cancer, 0.73; colon cancer, 0.81). No site of care-race interaction was significant for any of the cancers (p > .05). Equalizing treatment rates at MSHs could result in 5719 additional patients receiving definitive treatment over 10 years. CONCLUSIONS: The current findings underscore systemic disparities in definitive cancer treatment delivery between MSHs and non-MSHs for breast, prostate, nonsmall cell lung, and colon cancers. Although targeted improvements at MSHs represent a critical step toward equity, this study highlights the need for integrated, system-wide efforts to address the multifaceted nature of racial and ethnic health disparities. Enhancing care at MSHs could serve as a pivotal strategy in a broader initiative to achieve health care equity for all.
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Neoplasias da Mama , Neoplasias do Colo , Disparidades em Assistência à Saúde , Hospitais , Neoplasias Pulmonares , Neoplasias da Próstata , Humanos , Masculino , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Feminino , Neoplasias da Próstata/terapia , Neoplasias da Próstata/etnologia , Neoplasias do Colo/terapia , Neoplasias do Colo/etnologia , Neoplasias da Mama/terapia , Neoplasias da Mama/etnologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/etnologia , Hospitais/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso , Estados Unidos , Grupos Minoritários/estatística & dados numéricosRESUMO
PURPOSE OF REVIEW: This review uses the hierarchy of evidence as a framework to critically evaluate the effect of long chain n -3 polyunsaturated fatty acid (LC n -3 PUFA) ingestion alone, or as an adjunctive intervention to resistance training, on muscle health-related outcomes in healthy and clinical older adult populations. RECENT FINDINGS: Systematic reviews and meta-analyses of randomized controlled trials consistently report small, but clinically-relevant, effects of LC n -3 PUFA ingestion on strength outcomes, whereas mixed findings have been reported regarding changes in muscle mass and physical function. Cohort studies indicate an association between higher dietary LC n -3 PUFA intake and reduced likelihood of a sarcopenia diagnosis. Acute metabolic studies provide limited evidence for an effect of LC n -3 PUFA ingestion alone, or in combination with resistance training, on free-living integrated rates of MPS, static markers of muscle protein breakdown, or satellite cell activation in healthy older adults. SUMMARY: Recent data supports the efficacy of LCn-3 PUFA ingestion to facilitate small, but clinically relevant, improvements in muscle strength in healthy and clinical older adult populations. The mechanism(s) that underpin the action of LC n -3 PUFA in promoting strength outcomes remain unknown, but likely relate to neuromuscular function.
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Ácidos Graxos Ômega-3 , Sarcopenia , Humanos , Idoso , Ácidos Graxos Ômega-3/metabolismo , Suplementos Nutricionais , Sarcopenia/metabolismo , Força Muscular , Ácidos Graxos/metabolismo , Músculo Esquelético/metabolismoRESUMO
PURPOSE OF REVIEW: This review aims to explore the latest research investigating the effects of marine-derived long-chain n-3 polyunsaturated fatty acid (LCn-3 PUFA) supplementation on neuromuscular function in older adults. RECENT FINDINGS: Ageing results in a decline in skeletal muscle strength and mass. There is growing evidence that LCn-3 PUFA supplementation increases muscle strength and mass in healthy older adults, yet the mechanisms underlying these effects remain elusive. Recent studies investigating LCn-3 PUFA supplementation have demonstrated effects on neuromuscular function such as increases in the compound muscle action potential (M-wave) amplitude and surface electromyography alongside increases in muscular strength. Therefore, evidence suggests that LCn-3 PUFA may elicit a beneficial effect at the neuromuscular junction and possess neuroprotective properties in older adults. SUMMARY: LCn-3 PUFA supplementation may increase or maintain neuromuscular function throughout the ageing process. Further research is warranted to investigate the long-term effects LCn-3 PUFA supplementation on neuromuscular outcomes such as single motor unit properties and cortical/supraspinal networks, utilizing state-of-the-art techniques in neuromuscular physiology.
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OBJECTIVE: Determination of the real-world performance of a health care system in the treatment of status epilepticus (SE). METHODS: Prospective, multicenter population-based study of SE in Auckland, New Zealand (NZ) over 1 year, with data recorded in the EpiNet database. Focus on treatment patterns and determinants of SE duration and 30-day mortality. The incidence, etiology, ethnic discrepancies, and seizure characteristics of this cohort have been published previously. RESULTS: A total of 365 patients were included in this treatment cohort; 326 patients (89.3%) were brought to hospital because of SE, whereas 39 patients (10.7%) developed SE during a hospital admission for another reason. Overall, 190 (52.1%) had a known history of epilepsy and 254 (70.0%) presented with SE with prominent motor activity. The mean Status Epilepticus Severity Score (STESS) was 2.15 and the mean SE duration of all patients was 44 min. SE self-terminated without any treatment in 84 patients (22.7%). Earlier administration of appropriately dosed benzodiazepine in the pre-hospital setting was a major determinant of SE duration. Univariate analysis demonstrated that mortality was significantly higher in older patients, patients with longer durations of SE, higher STESS, and patients who developed SE in hospital, but these did not maintain significance with multivariate analysis. There was no difference in the performance of the health care system in the treatment of SE across ethnic groups. SIGNIFICANCE: When SE was defined as 10 continuous minutes of seizure, overall mortality was lower than expected and many patients had self-limited presentations for which no treatment was required. Although there were disparities in the incidence of SE across ethnic groups there was no difference in treatment or outcome. The finding highlights the benefit of a health care system designed to deliver universal health care.
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Anticonvulsivantes , Estado Epiléptico , Humanos , Estado Epiléptico/epidemiologia , Estado Epiléptico/terapia , Estado Epiléptico/mortalidade , Estado Epiléptico/tratamento farmacológico , Masculino , Feminino , Nova Zelândia/epidemiologia , Pessoa de Meia-Idade , Adulto , Idoso , Estudos Prospectivos , Anticonvulsivantes/uso terapêutico , Adolescente , Adulto Jovem , Resultado do Tratamento , Estudos de Coortes , Idoso de 80 Anos ou mais , Criança , Pré-EscolarRESUMO
PURPOSE: To evaluate how limited English proficiency (LEP) impacts the prevalence of prostate-specific antigen (PSA) screening in a contemporary, nationally representative cohort of men in the USA. METHODS: The Medical Expenditure Panel Survey was utilized to identify the prevalence of PSA screening between 2013 and 2016 among men ≥ 55. Men who speak a language other than English at home were stratified by self-reported levels of English proficiency (men who speak English very well, well, not well, or not at all). Survey weights were applied, and groups were compared using the adjusted Wald test. A multivariable logistic regression model was used to identify predictors of PSA screening adjusting for patient-level covariates. RESULTS: The cohort included 2,889 men, corresponding to a weighted estimate of 4,765,682 men. 79.6% of men who speak English very well reported receiving at least one lifetime PSA test versus 58.4% of men who do not speak English at all (p < 0.001). Men who reported not speaking English at all had significantly lower prevalence of PSA screening (aOR 0.56; 95% CI 0.35-0.91; p = 0.019). Other significant predictors of PSA screening included older age, income > 400% of the federal poverty level, insurance coverage, and healthcare utilization. CONCLUSIONS: Limited English proficiency is associated with significantly lower prevalence of PSA screening among men in the USA. Interventions to mitigate disparities in prostate cancer outcomes should account for limited English proficiency among the barriers to guideline-concordant care.
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Proficiência Limitada em Inglês , Neoplasias da Próstata , Masculino , Humanos , Estados Unidos , Antígeno Prostático Específico , Idioma , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/prevenção & controle , RendaRESUMO
AIM: To investigate the association of sarcopenia with cardiovascular disease (CVD) incidence in people with type 2 diabetes. MATERIALS AND METHODS: A prospective cohort study with 11 974 White European UK Biobank participants with type 2 diabetes, aged 40-70 years, included. Sarcopenia was defined based on the European Working Group on Sarcopenia in Older People as either non-sarcopenic or sarcopenic. Outcomes included CVD, stroke, heart failure (HF) and myocardial infarction (MI). The association between sarcopenia and the incidence of outcomes was investigated using Cox proportional hazard models adjusted for sociodemographic and lifestyle factors. The rate advancement period was used to estimate the time period by which CVD is advanced because of sarcopenia. RESULTS: Over a median follow-up of 10.7 years, 1957 participants developed CVDs: 373 had a stroke, 307 had an MI and 742 developed HF. Compared with non-sarcopenia, those with sarcopenia had higher risks of CVD (HR 1.89 [95% CI 1.61; 2.21]), HF (HR 2.59 [95% CI 2.12; 3.18]), stroke (HR 1.90 [95% CI 1.38; 2.63]), and MI (HR 1.56 [95% CI 1.04; 2.33]) after adjustment for all covariates. Those with sarcopenia had CVD incidence rates equivalent to those without sarcopenia who were 14.5 years older. Similar results were found for stroke, HF and MI. CONCLUSIONS: In people with type 2 diabetes, sarcopenia increased the risk of developing CVD, which might occur earlier than in those without sarcopenia. Therefore, sarcopenia screening and prevention in patients with type 2 diabetes may be useful to prevent the complications of CVD.
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Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Infarto do Miocárdio , Sarcopenia , Acidente Vascular Cerebral , Humanos , Idoso , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Sarcopenia/complicações , Sarcopenia/epidemiologia , Incidência , Estudos Prospectivos , Bancos de Espécimes Biológicos , Biobanco do Reino Unido , Insuficiência Cardíaca/epidemiologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Fatores de RiscoRESUMO
PURPOSE: To understand racial disparities in germline cancer genetic testing and the role of prior knowledge, attitudes, and sources of information. METHODS: A cross-sectional analysis of the Health Information National Trends Survey 5 (HINTS 5) was conducted between February 24th and June 15th, 2020. The study aimed to investigate knowledge and receipt of genetic testing, attitudes toward the importance of genetic testing in preventing, detecting, and treating cancer, and information sources of genetic testing in the United States of America. RESULTS: Non-Hispanic Black (NHB) and Hispanic race/ethnicity were associated with lower odds of being informed about genetic testing, whereas those of NHB race were more likely to endorse the importance of genetic testing in cancer prevention and treatment. Regarding sources of information about genetic testing: Non-Hispanic Asians were less likely to be informed about genetic testing from television (Mean Predicted Probability (MPP) 0.38 95%CI; 0.21-0.55, (Adjusted Risk Difference) ARD vs. Non-Hispanic White (NHW); -0.228, p = 0.01), NHB were less likely to report being informed about genetic testing from social media (MPP 0.27 95%CI; 0.20-0.34, ARD vs. NHW; -0.139, p < 0.01). CONCLUSIONS: NHB and Hispanic groups face unequal access to information about genetic testing. There are significant race-based differences in information sources. These differences could be used to promote equitable access to cancer genetic testing.
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Acesso à Informação , Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Disparidades em Assistência à Saúde , Neoplasias , Humanos , Negro ou Afro-Americano , Estudos Transversais , Células Germinativas , Neoplasias/diagnóstico , Neoplasias/genética , Fatores Raciais , Estados Unidos , Hispânico ou LatinoRESUMO
Due to the continuous growth rate of the electronic industry, hi-tech companies depend on mining and extracting precious metals to meet the public demand. The high turnover of modern devices generates an alarming amount of electronic waste (e-waste), which contains more precious metals than mined ores and therefore needs efficient recovery procedures. A highly stable homopiperazine-derived Cd-MOF, poly-[Cd(H2L)]·9H2O, with a protonated amine ligand core, exists as a twofold interpenetrated 3D framework with 1D channels into which the N+-H bond is directed. The geometry of these channels appears to be suitable to host square planar metalate complexes. Under acidic conditions, [MCl4]x- anions containing Au, Cu, Ni, and Pt, representing common components of e-waste under extraction conditions, were tested for capture and recovery. Cd-MOF exhibits remarkable selectivity and uptake performance toward Au with an adsorbent capacity of 25 mg g-1ads and shows a marked selectivity for Au over Cu in competitive experiments. The adsorption mechanism of Au appears to be predominantly physical adsorption at the surface of the material.
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Isolated mixed-ligand complexes provide tractable model systems in which to study competitive and cooperative binding effects as well as controlled energy flow. Here, we report spectroscopic and isotopologue-selective infrared photofragmentation dynamics of mixed gas-phase Au(12/13CO)n(N2O)m+ complexes. The rich infrared action spectra, which are reproduced well using simulations of calculated lowest energy structures, clarify previous ambiguities in the assignment of vibrational bands, especially accidental coincidence of CO and N2O bands. The fragmentation dynamics exhibit the same unexpected behaviour as reported previously in which, once CO loss channels are energetically accessible, these dominate the fragmentation branching ratios, despite the much lower binding energy of N2O. We have investigated the dynamics computationally by considering anharmonic couplings between a relevant subset of normal modes involving both ligand stretch and intermolecular modes. Discrepancies between correlated and uncorrelated model fit to the ab initio potential energy curves are quantified using a Boltzmann sampled root mean squared deviation providing insight into efficiency of vibrational energy transfer between high frequency ligand stretches and the softer intermolecular modes which break during fragmentation.
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We report the preparation of a co-crystal formed between the energetic molecule 3-nitro-1,2,4-triazol-5-one (NTO) and 4,4'-bipyridine (BIPY), that has been structurally characterised by high-pressure single crystal and neutron powder diffraction data up to 5.93 GPa. No phase transitions or proton transfer were observed up to this pressure. At higher pressures the crystal quality degraded and the X-ray diffraction patterns showed severe twinning, with the appearance of multiple crystalline domains. Computational modelling indicates that the colour changes observed on application of pressure can be attributed to compression of the unit cell that cause heightened band dispersion and band gap narrowing that coincides with a shortening of the BIPY πâ¯π stacking distance. Modelling also suggests that the application of pressure induces proton migration along an N-Hâ¯N intermolecular hydrogen bond. Impact-sensitivity measurements show that the co-crystal is less sensitive to initiation than NTO, whereas computational modelling suggests that the impact sensitivities of NTO and the co-crystal are broadly similar.
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PURPOSE: To compare the performance (covariate balance, effective sample size [ESS]) of stable balancing weights (SBW) versus propensity score weighting (PSW). Two applied cases were used to compare performance: (Case 1) extreme imbalance in baseline covariates between groups and (Case 2) substantial discrepancy in sample size between groups. METHODS: Using the Premier Healthcare Database, we selected patients who (Case 1) underwent a surgical procedure with one of two different bipolar forceps between January 2000 and June 2020, or (Case 2) a neurological procedure using one of two different nonabsorbable surgical sutures between January 2000 and March 2020. Average treatment effects on the treated (ATT) weights were generated based on selected covariates. SBW was implemented using two techniques: (1) "grid search" to find weights of minimum variance at the lowest target absolute standardized mean difference (SMD); (2) finding weights of minimum variance at prespecified SMD tolerance. PSW and SBW methods were compared on postweighting SMDs, the number of imbalanced covariates, and ESS of the ATT-weighted control group. RESULTS: In both studies, improved covariate balance was achieved with both SBW techniques. All methods suffered from postweighting ESS that was lower than the unweighted control group's original sample size; however, SBW methods achieved higher ESS for the control groups. Sensitivity analyses using SBW to apply variable-specific SMD thresholds increased ESS, outperforming PSW. CONCLUSIONS: In this applied example, the optimization-based SBW method provided ample flexibility with respect to prespecification of covariate balance goals and resulted in better postweighting covariate balance and larger ESS as compared with PSW.
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Pontuação de Propensão , Humanos , Tamanho da Amostra , Bases de Dados Factuais , Feminino , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To investigate if preschool children differ to school age children with mild traumatic brain injury (TBI) with respect to injury causes, clinical presentation, and medical management. DESIGN: A secondary analysis of a dataset from a large, prospective and multisite cohort study on TBI in children aged 0-18 years, the Australian Paediatric Head Injury Rules Study. SETTING: Nine pediatric emergency departments (ED) and 1 combined adult and pediatric ED located across Australia and New Zealand. PARTICIPANTS: 7080 preschool aged children (2-5 years) were compared with 5251 school-age children (6-12 years) with mild TBI (N= (N=12,331) MAIN OUTCOME MEASURES: Clinical report form on medical symptoms, injury causes, and management. RESULTS: Preschool children were less likely to be injured with a projectile than school age children (P<.001). Preschool children presented with less: loss of consciousness (P<.001), vomiting (P<.001), drowsiness (P=.002), and headache (P<.001), and more irritability and agitation (P=.003), than school-age children in the acute period after mild TBI. Preschool children were less likely to have neuroimaging of any kind (P<.001) or to be admitted for observation than school age children (P<.001). CONCLUSIONS: Our large prospective study has demonstrated that preschool children with mild TBI experience a different acute symptom profile to older children. There are significant clinical implications with symptoms post-TBI used in medical management to aid decisions on neuroimaging and post-acute intervention.
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Concussão Encefálica , Lesões Encefálicas Traumáticas , Adulto , Criança , Pré-Escolar , Humanos , Austrália , Estudos de Coortes , Serviço Hospitalar de Emergência , Estudos ProspectivosRESUMO
AIM: To understand and evaluate the uptake and local adaptations of proven targeted implementation interventions that have effectively reduced unnecessary investigations and therapies in infants with bronchiolitis within emergency departments. METHODS: A multi-centred, mixed-methods quality improvement study in four Australian hospitals that provide paediatric emergency and inpatient care from May to December 2021. All hospitals were provided with the same implementation intervention package and training. Real-time tracking logs of adaptions were completed followed by semi-structured interviews. Interviews were recorded, transcribed and subsequently coded using FRAME-IS to further describe the adaptions made. RESULTS: Tracking logs were summarised and data from 12 interviews were compared from participating sites. The intervention resulted in 116 education sessions and a total of 23 adaptations made to educational materials, both content and contextual. Shortening education presentations, addition of bronchiolitis definitions, formatting of materials and novel interventions were the most common modifications. Audit and feedback were completed across all sites with varying utilisation. Targeted teaching was noted to dictate adaptions prior to and during implementation. CONCLUSION: Quantitative and qualitative analysis of clinical 'real-world' adaptations to proven targeted implementation interventions allows invaluable insight for future de-implementation initiatives and national roll-out of implementation packages in the ED setting.
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Bronquiolite , Lactente , Humanos , Criança , Austrália , Bronquiolite/terapia , Hospitalização , Serviço Hospitalar de Emergência , Melhoria de QualidadeRESUMO
In patients with drug-resistant epilepsy, difficulties in identifying the epileptogenic zone are well known to correlate with poorer clinical outcomes post-surgery. The integration of PET and MRI in the presurgical assessment of pediatric patients likely improves diagnostic precision by confirming or widening treatment targets. PET and MRI together offer superior insights compared to either modality alone. For instance, PET highlights abnormal glucose metabolism, while MRI precisely localizes structural anomalies, providing a comprehensive understanding of the epileptogenic zone. Furthermore, both methodologies, whether utilized through simultaneous PET/MRI scanning or the co-registration of separately acquired PET and MRI data, present unique advantages, having complementary roles in lesional and non-lesional cases. Simultaneous FDG-PET/MRI provides precise co-registration of functional (PET) and structural (MR) imaging in a convenient one-stop-shop approach, which minimizes sedation time and reduces radiation exposure in children. Commercially available fusion software that allows retrospective co-registration of separately acquired PET and MRI images is a commonly used alternative. This review provides an overview and illustrative cases that highlight the role of combining 18F-FDG-PET and MRI imaging and shares the authors' decade-long experience utilizing simultaneous PET/MRI in the presurgical evaluation of pediatric epilepsy.
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OBJECTIVE: The aim of this study was to compare injury circumstances, characteristics, and clinical management of emergency department (ED) presentations for sports-related concussion (SRC) and non-SRC. METHODS: This multicenter prospective observational study identified patients 5-17 years old who presented to EDs within 24 hours of head injury, with one or more signs or symptoms of concussion. Participants had a Glasgow Coma Scale score of 13-15 and no abnormalities on CT (if performed). Data were stratified by age: young children (5-8 years), older children (9-12 years), and adolescents (13-17 years). RESULTS: Of 4709 patients meeting the concussion criteria, non-SRC accounted for 56.3% of overall concussions, including 80.9% of younger child, 51.1% of older child, and 37.0% of adolescent concussions. The most common mechanism of non-SRC was falls for all ages. The most common activity accounting for SRC was bike riding for younger children, and rugby for older children and adolescents. Concussions occurring in sports areas, home, and educational settings accounted for 26.2%, 21.8%, and 19.0% of overall concussions. Concussions occurring in a sports area increased with age, while occurrences in home and educational settings decreased with age. The presence of amnesia significantly differed for SRC and non-SRC for all age groups, while vomiting and disorientation differed for older children and adolescents. Adolescents with non-SRC were admitted to a ward and underwent CT at higher proportions than those with SRC. CONCLUSIONS: Non-SRC more commonly presented to EDs overall, with SRC more common with increasing age. These data provide important information to inform public health policies, guidelines, and prevention efforts.