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There is wide variation in mortality among patients hospitalized with COVID-19. Whether this is related to patient or hospital factors is unknown.To compare the risk of mortality for patients hospitalized with COVID-19 and to determine whether the majority of that variation was explained by differences in patient characteristics across sites.An international multicenter cohort study of hospitalized adults with laboratory-confirmed COVID-19 enrolled from 10 hospitals in Ontario, Canada and 8 hospitals in Copenhagen, Denmark between January 1, 2020 and November 11, 2020.Inpatient mortality. We used a multivariable multilevel regression model to compare the in-hospital mortality risk across hospitals and quantify the variation attributable to patient-level factors.There were 1364 adults hospitalized with COVID-19 in Ontario (n = 1149) and in Denmark (n = 215). In Ontario, the absolute risk of in-hospital mortality ranged from 12.0% to 39.8% across hospitals. Ninety-eight percent of the variation in mortality in Ontario was explained by differences in the characteristics of the patients. In Denmark, the absolute risk of inpatients ranged from 13.8% to 20.6%. One hundred percent of the variation in mortality in Denmark was explained by differences in the characteristics of the inpatients.There was wide variation in inpatient COVID-19 mortality across hospitals, which was largely explained by patient-level factors, such as age and severity of presenting illness. However, hospital-level factors that could have affected care, including resource availability and capacity, were not taken into account. These findings highlight potential limitations in comparing crude mortality rates across hospitals for the purposes of reporting on the quality of care.

The consequences of poor breed management and inbreeding can range from gradual declines in individual productivity to more serious fertility and mortality concerns. However, many small and closed groups, as well as larger unmanaged populations, are plagued by genetic regression, often due to a dearth in breeding support tools which are accessible and easy to use in supporting decision‐making. To address this, we have developed a population management tool (BCAS, Breed Conservation and Management System) based on individual relatedness assessed using pedigree‐based kinship, which offers breeding recommendations for such populations. Moreover, we demonstrate the success of this tool in 16 years of employment in a closed equine population native to the UK, most notably, the rate of inbreeding reducing from more than 3% per generation, to less than 0.5%, or that attributed to genetic drift, as assessed over the last 16 years of implementation. Furthermore, with adherence to this program, the long‐term impact of poor management has been reversed and the genetic resource within the breed has grown from an effective population size of 20 in 1994 to more than 140 in 2020. The development and availability of our BCAS for breed management and selection establish a new paradigm for the successful maintenance of genetic resources in animal populations., Across the last 16 years, a genetic breed management program has led to the British population of the Cleveland Bay transitioning from an effective population size well below the UN FAO limit of concern of 50, to a stratified breeding system with N e now over 145.

Decline in global carnivore populations has led to increased demand for assessment of carnivore densities in understudied habitats. Spatial capture–recapture (SCR) is used increasingly to estimate species densities, where individuals are often identi- fied from their unique pelage patterns. However, uncertainty in bilateral individual identification can lead to the omission of capture data and reduce the precision of results. The recent development of the two-flank spatial partial identity model (SPIM) offers a cost-effective approach, which can reduce uncertainty in individual identity assignment and provide robust density estimates. We conducted camera trap surveys annually between 2016 and 2018 in Kasungu National Park, Malawi, a primary miombo woodland and a habitat lacking baseline data on carnivore den- sities. We used SPIM to estimate density for leopard (Panthera pardus) and spotted hyaena (Crocuta crocuta) and compared estimates with conventional SCR methods. Density estimates were low across survey years, when compared to estimates from sub-Saharan Africa, for both leopard (1.9 0.19 SD adults/100 km2) and spotted hyaena (1.15 0.42 SD adults/100 km2). Estimates from SPIM improved precision compared with analytical alternatives. Lion (Panthera leo) and wild dog (Lycaon pictus) were absent from the 2016 survey, but lone dispersers were recorded in 2017 and 2018, and both species appear limited to transient individuals from within the wider transfrontier conservation area. Low densities may reflect low car- rying capacity in miombo woodlands or be a result of reduced prey availability from intensive poaching. We provide the first leopard density estimates from Malawi and a miombo woodland habitat, whilst demonstrating that SPIM is benefi- cial for density estimation in surveys where only one camera trap per location is deployed. The low density of large carnivores requires urgent management to reduce the loss of the carnivore guild in Kasungu National Park and across the wider transfrontier landscape.

The science and practice of environmental flows have advanced significantly over the last several decades. Most environmental flow approaches require quantifying the relationships between hydrologic change and biologic response, but this can be challenging to determine and implement due to high data requirements, limited transferability, and the abundance of hydrologic metrics available for evaluation. We suggest that a functional flows approach, focusing on elements of the natural flow regime known to sustain important ecosystem processes, offers a pathway for linking understanding of ecosystem processes with discrete, quantifiable measures of the flow regime for a broad range of native taxa and assemblages. Functional flow components can be identified as distinct aspects of the annual hydrograph that support key biophysical processes, such as wet season flood flows or spring recession flows, and then quantified by flow metrics, such as 5% exceedance flow or daily percent decrease in flow, respectively. By selecting a discrete set of flow metrics that measure key functional flow components, the spatial and temporal complexity of flow regimes can be managed in a holistic manner supportive of multiple ecological processes and native aquatic species requirements. We provide an overview of the functional flows approach to selecting a defined set of flow metrics and illustrate its application in two seasonally variable stream systems. We further discuss how a functional flows approach can be utilized as a conceptual model both within and outside of existing environmental flow frameworks to guide consideration of ecological processes when designing prescribed flow regimes.

Investigating clustered data requires consideration of the variation across clusters, including consideration of the component of the total individual variance that is at the cluster level. The median odds ratio and analogues are useful intuitive measures available to communicate variability in outcomes across clusters using the variance of random intercepts from a multilevel regression model. However, the median odds ratio cannot describe variability across clusters for different patient subgroups because the random intercepts do not vary by subgroup. To empower investigators interested in equity and other applications of this scenario, we describe an extension of the median odds ratio to multilevel regression models employing both random intercepts and random coefficients. By example, we conducted a retrospective cohort analysis of variation in care limitations (goals of care preferences) according to ethnicity in patients admitted to intensive care. Using mixed-effects logistic regression clustered by hospital, we demonstrated that patients of non-Caucasian ethnicity were less likely to have care limitations but experienced similar variability across hospitals. Limitations of the extended median odds ratio include the large sample sizes and computational power needed for models with random coefficients. This extension of the median odds ratio to multilevel regression models with random coefficients will provide insight into cluster-level variability for researchers interested in equity and other phenomena where variability by patient subgroup is important.

Funding: The People's Trust for Endangered Species, Nottingham Trent University, British Hedgehog Preservation Society, The Heritage Fund. Abundance and density are vital metrics for assessing a species’ conservation status and for developing effective management strategies. Remote-sensing cameras are being used increasingly as part of citizen science projects to monitor wildlife, but current methodologies to monitor densities pose challenges when animals are not individually recognizable. We investigated the use of camera traps and the Random Encounter Model (REM) for estimating the density of West European hedgehogs (Erinaceus europaeus) within a citizen science framework. We evaluated the use of a simplified version of the REM in terms of the parameters’ estimation (averaged vs. survey-specific) and assessed its potential application as part of a large-scale, long-term citizen science project. We compared averaged REM estimates to those obtained via spatial capture–recapture (SCR) using data from nocturnal spotlight surveys. There was a high degree of concordance in REM-derived density estimates from averaged parameters versus those derived from survey-specific parameters. Averaged REM density estimates were also comparable to those produced by SCR at eight out of nine sites; hedgehog density was 7.5 times higher in urban (32.3 km−2) versus rural (4.3 km2) sites. Power analyses indicated that the averaged REM approach would be able to detect a 25% change in hedgehog density in both habitats with >90% power. Furthermore, despite the high start-up costs associated with the REM method, it would be cost-effective in the long term. The averaged REM approach is a promising solution to the challenge of large-scale and long-term species monitoring. We suggest including the REM as part of a citizen science monitoring project, where participants collect data and researchers verify and implement the required analysis. Publisher PDF

Dams and diversions in rivers often alter flow regimes, which in turn can affect stream biota, particularly when the novel conditions are dramatically different from those under which native species evolved. Management of regulated rivers can include development of environmental flows that seek to restore ecological integrity. However, designing a flow regime that adequately supports aquatic biodiversity requires quantifiable metrics of hydrologic variability that directly relate to aquatic species diversity. This study examined both regulated and unregulated montane rivers over 3 years within the marked seasonality of California's Mediterranean climate to determine which quantifiable elements of a flow regime were most correlated with changes in the biologic community, using stream invertebrates during the summer low flow period as an indicator. Boosted regression trees were used to assess relationships between quantifiable metrics of flow regimes and the invertebrate community. Non-metric multidimensional scaling and a multi-response permutation procedure were used to analyze general trends in invertebrate assemblage patterns between rivers and years. Results indicated that hydrologic alteration corresponded to differences in invertebrate community composition, and that metrics related to the spring snowmelt recession and variability in summer water temperature had the greatest relative influence on invertebrate community diversity. Rivers exhibiting longer duration spring recessions, lower daily rates of change during the spring recession, and stable water temperatures during summer supported relatively higher invertebrate community diversity. These relationships suggest that quantifiable metrics associated with seasonal flow variability and predictability should be an integral part of environmental flow design and monitoring.

The electronic structure and photophysical properties of two phosphorescent iridium(III) cyclometalated complexes is presented. The molecules were synthesized by cyclometalating the ligand 1,8-naphthalenebenzimidizole (NBI), to an iridium(III) metal center. Two NBI ligands were covalently attached along with a 1,10-phenanthroline (phen) ligand producing the [Ir(NBI)2(phen)](PF6) complex and three NBI ligands were used to prepare the corresponding tris-cyclometalate fac-Ir(NBI)3. The optical properties of these new Ir(III) molecules were investigated using density functional theory calculations, photoluminescence spectroscopy, and transient absorption spectroscopy. The molecules at the heart of this study were found to contain long-lived ligand-localized triplet excited states on the NBI species, featuring energies suitable for bimolecular photochemical reactions. Both iridium(III) chromophores possess excellent light absorptivity in the visible region of the spectrum with high photoluminescence quantum efficiencies approaching 30%.

Carnivores frequently come into conflict with humans in agricultural and livestock- producing areas around the world. Understanding their fidelity and dispersal patterns in response to food availability is therefore important given the effort invested in conflict mitigation strategies. In this study, we investigated the influence of clumped and abundant sources of carrion on the genetic diversity of the black-backed jackal Canis mesomelas within six private game farms in the North-West and Gauteng provinces of South Africa. It is predicted that clumped and abundant sources of carrion will increase immigration and thus genetic diversity in the local subpopulation. By quantifying the variability in microsatellite loci in black-backed jackals subjected to artificially increased carrion availability, and comparing them with individuals from control sites, we were able to describe patterns of historic gene flow within the total sampled population. The results of this investigation indicate that clumped and abundant sources of carrion promote genetic structuring (FST = 0.0302) which implies a lack of gene flow and a degree of isolation. Genetic artefacts of three populations could be identified through Bayesian clustering analysis of individuals based on their genetic identity. Individuals sampled from the two supplementary feeding sites could be assigned to one of two ancestral populations with an average population assignment of 69 and 82%, while individuals from the remaining four control sites, originate from a third population with percentage assignments of 63%, 46%, 53% and 42%. It is therefore likely that clumped and abundant sources of carrion in the agricultural landscape of South Africa can affect the population dynamics of the black-backed jackal and result in subpopulations with limited migration and dispersal when compared with the total population.

In an effort to restore predictable ecologically relevant spring snowmelt recession flow patterns in rivers regulated by dams, this study defined a methodology by which spring flow regimes can be modeled in regulated systems from the quantifiable characteristics of spring snowmelt recessions in unregulated rivers. An analysis of eight unregulated rivers across the Sierra Nevada mountain range in California found that unregulated systems behaved similarly with respect to seasonal spring patterns and recession limb curvature, and thus prescribed flows could be designed in a manner that mimics those predictable characteristics. Using the methodology to quantify spring recession flows in terms of a daily percent decrease in flow, a series of flow recession scenarios were created for application in an existing hydrodynamic model for the regulated Rubicon River. The modeling results showed that flow recessions with slow ramping rates similar to those observed in unregulated rivers (less than 10% per day) were likely to be protective of native aquatic species, such as the Foothill yellow-legged frog, while flows that receded at greater rates would likely result in desiccation of egg masses and potential stranding of tadpoles and fry. Furthermore, recession rates of less than 10% per day provided the most spatially diverse hydraulic habitat in the modeled domain for an appropriate duration in spring to support all native species guilds and maximize aquatic biodiversity.

The electronic structure and photophysical properties of a luminescent IrIII bis-cyclometalated complex covalently attached to one 4-piperidinyl-1,8-naphthalimide (PNI) chromophore through a coordinated 1,10-phenanthroline, [Ir(ppy)2(phen-PNI)](PF6), is presented. This bichromophore represents a new class of visible light-harvesting IrIII complexes that exhibit markedly enhanced room-temperature excited-state lifetimes (τ = 8.8 ms) as a result of intervening ligand-centered triplet states present on the pendant naphthalimide chromophore. In this IrIII complex, the intense singlet fluorescence of the pendant PNI chromophore is nearly quantitatively quenched and was found to sensitize the IrIII metal/ligand-to-ligand charge-transfer (MLLCT) excited state. The excited state ultimately returns to the PNI chromophore as a long-lived excited triplet that disposes of its energy by equilibrating with the photoluminescent IrIII MLLCT excited state. Evidence of the excited-state equilibrium is provided through static and dynamic photoluminescence spectroscopy, transient absorption spectroscopy, and time-dependent density functional theory calculations.

Purpose This paper establishes foundational knowledge on development of polysubstance use among adolescents in the U.S. child welfare system (CWS). Method Data on U.S. CWS adolescents from the National Study of Child and Adolescent Well-Being were examined for rates of alcohol, marijuana, and hard drug use; and change in use over time. Results Past 30-day absolute use was highest for alcohol, but daily/near-daily use highest for marijuana. Marijuana use increased at later time points. A correlated growth model suggested covariation in use of the substances. A curve-of-factors model suggested that higher-order factors explain most variation in substance use, except at the last time point. Those with lower use changed the most across time. Conclusions Subsequent research among CWS adolescents in the U.S. should consider substances jointly. Prevention should focus on marijuana, and later periods of adolescence and CWS involvement. Youth not thought of as at great risk upon entering the CWS may be most vulnerable.

This study investigated the effects of hydrograph shape on attenuation of regulated pulsed flow events below a hydropower dam by categorizing and modelling the downstream movement of representative pulses on the upper Tuolumne River in the Sierra Nevadas of California, USA. We extracted underlying hydrograph shape patterns using principal component analysis on individual pulsed flow events released from 1988 to 2012 (n = 4439). From principal component loadings, six shape categories were determined: rectangular, front-step, back-step, goalpost, centred tower, and other. Attenuation of representative pulses from each shape type was then modelled using a one-dimensional hydraulic model of 42 river km. Model results demonstrated a durational threshold for representative pulses (~3–5 h) over which the degree of attenuation of ramping rates and peak discharge approached a limit. Simulations of front and back-step representative pulses showed trade-offs between attenuation of peak magnitudes and steepness of rising ramping rates. Reshaping pulses to reduce the adverse ecological effects of rapid changes in stage and velocity downstream was infeasible if the system was required to maintain current electricity production and recreational service levels. Copyright © 2015 John Wiley & Sons, Ltd.

Discrimination statistics describe the ability of a survival model to assign higher risks to individuals who experience earlier events: examples are Harrell's C-index and Royston and Sauerbrei's D, which we call the D-index. Prognostic covariates whose distributions are controlled by the study design (e.g. age and sex) influence discrimination and can make it difficult to compare model discrimination between studies. Although covariate adjustment is a standard procedure for quantifying disease-risk factor associations, there are no covariate adjustment methods for discrimination statistics in censored survival data.To develop extensions of the C-index and D-index that describe the prognostic ability of a model adjusted for one or more covariate(s).We define a covariate-adjusted C-index and D-index for censored survival data, propose several estimators, and investigate their performance in simulation studies and in data from a large individual participant data meta-analysis, the Emerging Risk Factors Collaboration.The proposed methods perform well in simulations. In the Emerging Risk Factors Collaboration data, the age-adjusted C-index and D-index were substantially smaller than unadjusted values. The study-specific standard deviation of baseline age was strongly associated with the unadjusted C-index and D-index but not significantly associated with the age-adjusted indices.The proposed estimators improve meta-analysis comparisons, are easy to implement and give a more meaningful clinical interpretation.? 2014 The Author. Biometrical Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Indirect survey methods are often used in studies of mammals, but are susceptible to biases caused by failure to detect species where they are present. Occupancy analysis is an analytical technique which enables non-detection rates to be estimated and which can be used to develop and refine novel survey methods. In this study, we investigated the use of footprint tunnels by volunteers as a method for surveying occupancy of sites by hedgehogs Erinaceus europaeus. The survey protocol led to a very low non-detection rate and could reasonably be used to detect occupancy changes of 25% with statistical power of 0.95 in a national survey.

Serial MRI facilitates the in vivo analysis of the intra- and intersubject evolution of traumatic brain injury lesions. Despite the availability of MRI, the natural history of experimental focal contusion lesions in the controlled cortical impact (CCI) rat model has not been well described. We performed CCI on rats and MRI during the acute to chronic stages of cerebral injury to investigate the time course of changes in the brain. Female Wistar rats underwent CCI of their left motor cortex with a flat impact tip driven by an electromagnetic piston. In vivo MRI was performed at 7 T serially over 6 weeks post-CCI. The appearances of CCI-induced lesions and lesion-associated cortical volumes were variable on MRI, with the percentage change in cortical volume of the CCI ipsilateral side relative to the contralateral side ranging from 18% within 2 h of injury on day 0 to a peak of 35% on day 1, and a trough of -28% by week 5/6, with an average standard deviation of ± 14% at any given time point. In contrast, the percentage change in cortical volume of the ipsilateral side relative to the contralateral side in control rats was not significant (1 ± 2%). Hemorrhagic conversion within and surrounding the CCI lesion occurred between days 2 and 9 in 45% of rats, with no hemorrhage noted on the initial scan. Furthermore, hemorrhage and hemosiderin within the lesion were positive for Prussian blue and highly autofluorescent on histological examination. Although some variation in injuries may be technique related, the divergence of similar lesions between initial and final scans demonstrates the inherent biological variability of the CCI rat model.

Understanding the trade-offs between water for the environment and water for hydropower in regulated rivers can inform decision making about hydropower system planning, policy and operations, especially with anticipated climate warming–induced changes in runoff. This study used a multireservoir optimisation model to assess the hydropower effects of increasing minimum instream flows (MIFs) and imposing weekly scale down ramp rates (DRRs) in three locations in California's Upper Yuba River (UYR). The UYR is currently used for hydropower generation yet has high potential for freshwater habitat restoration. Trade-offs between DRRs, MIFs and hydropower generation and revenue are explored with uniform air temperature increases of 0 °C, 2 °C, 4 °C and 6 °C to approximate anticipated regional climate warming. With 6 °C warming, the most ecologically beneficial MIF and DRR reduced hydropower generation by 7.9% and revenue by 5.5% compared with base case management and a historical climate. This has important implications for licensure of the UYR project and other hydropower projects, where multiple benefits under current and potential future conditions must be balanced. This study provides a methodological approach that can be used by water managers, regulators and stakeholders to better understand inherent trade-offs in allocating water for multiple beneficial uses in a nonstationary hydroclimate. Copyright © 2012 John Wiley & Sons, Ltd.

To investigate the association between periodontitis and mortality from all causes in a prospective study in a homogenous group of 60- to 70-year-old West European men.A representative sample of 1400 dentate men, (mean age 63.8, SD 3.0 years), drawn from the population of Northern Ireland, had a comprehensive periodontal examination between 2001 and 2003. Men were divided into thirds on the basis of their mean periodontal attachment loss (PAL). The primary endpoint, death from any cause, was analysed using Kaplan-Meier survival plots and Cox's proportional hazards model.In total, 152 (10.9%) of the men died during a mean follow-up of 8.9 (SD 0.7) years; 37 (7.9%) men in the third with the lowest PAL (1.8 mm) died compared with 73 (15.7%) in the third with the highest PAL (2.6 mm). The unadjusted hazard ratio (HR) for death in the men with the highest level of PAL compared with those with the lowest PAL was 2.11 (95% CI 1.42-3.14), p 0.0001. After adjustment for confounding variables (age, smoking, hypertension, BMI, diabetes, cholesterol, education, marital status and previous history of a cardiovascular event) the HR was 1.57 (1.04-2.36), p = 0.03.The European men in this prospective cohort study with the most severe loss of periodontal attachment were at an increased risk of death compared with those with the lowest loss of periodontal attachment.

A series of cyclometalated RuII coordination compounds of the general structural formula [Ru(bpy)2(C∧N)]PF6 {C∧N = 2-phenylpyridine (1), 2-(2,4-difluorophenyl)pyridine (2), 2-(4-methoxyphenyl)-5-methylpyridine (3), benzo[h]quinoline (4); bpy = 2,2′-bipyridine} have been synthesized, structurally and electrochemically characterized, and examined by using a battery of spectroscopic techniques. The combination of static and dynamic photoluminescence at room temperature and 77 K, resonance Raman spectroscopy, cyclic voltammetry, spectroelectrochemistry, and ultrafast transient absorption spectroscopy reveal that – although the nature of the cyclometalating ligand substantially affects the oxidation potential at the metal center – the lowest-energy metal-to-ligand charge-transfer excited state always retains pure Rubpy character across this series of molecules, and the cyclometalating subunit plays the role of ancillary ligand.

Objective: Adipocytokines are hormones secreted from adipose tissue that possibly link adiposity and the risk of cardiovascular disease, but limited prospective data exist on plasma adipocytokines and ischemic stroke risk. We investigated associations and predictive properties of 4 plasma adipocytokines, namely resistin, adipsin, leptin, and total adiponectin, with regard to incident ischemic stroke in the PRIME Study. Methods: A cohort of 9,771 healthy men 50 to 59 years of age at baseline was followed up over a period of 10 years. In a nested case–control study, 95 ischemic stroke cases were matched with 190 controls on age, study center, and date of examination. Hazard ratios (HRs) per standard deviation increase in plasma adipocytokine levels were estimated using conditional logistic regression analysis. The additive value of adipocytokines in stroke risk prediction was evaluated by discrimination and reclassification metrics. Results: Resistin (HR, 1.88; 95% confidence interval [CI], 1.16–3.03), adipsin (HR, 2.01; 95% CI, 1.33–3.04), and total adiponectin (HR, 1.53; 95% CI, 1.01–2.34), but not leptin, were independent predictors of ischemic stroke. The performance of a traditional risk factor model predicting ischemic stroke was significantly improved by the simultaneous inclusion of resistin, adipsin, and total adiponectin (c-statistic: 0.673 [95% CI, 0.631–0.766] vs 0.826 [95% CI, 0.792–0.892], p < 0.001; net reclassification improvement: 38.1%, p < 0.001). Interpretation: Higher plasma levels of resistin, adipsin, and total adiponectin were associated with an increased 10-year risk of ischemic stroke among healthy middle-aged men. Resistin, adipsin, and total adiponectin provided incremental value over traditional risk factors for the prediction of ischemic stroke risk. ANN NEUROL 2012

The rapidly emerging field of positive psychology has yielded theories, research, and best practice standards that may complement the work of nursing professionals as they assess and build upon individuals' unique areas of strength in the context of daily hassles, major life events, and exceptional circumstances. In this article, we summarize Wolin and Wolin's Challenge Model and illustrate its potential usefulness as a tool for examining resilience in pediatric patients. Through our own teaching and consultation experiences, we have found that the pairing of the Wolins' clinical model of human psychology and Dave Pelzer's A Child Called "It" provides a salient means of furthering current and prospective professionals' empathic regard for young patients and clients by promoting a more balanced and comprehensive understanding of children who face adversity.