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1.
Glob Chang Biol ; 28(7): 2221-2235, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35060249

RESUMEN

One of the most pressing questions in ecology and conservation centers on disentangling the relative impacts of concurrent global change drivers, climate and land-use/land-cover (LULC), on biodiversity. Yet studies that evaluate the effects of both drivers on species' winter distributions remain scarce, hampering our ability to develop full-annual-cycle conservation strategies. Additionally, understanding how groups of species differentially respond to climate versus LULC change is vital for efforts to enhance bird community resilience to future environmental change. We analyzed long-term changes in winter occurrence of 89 species across nine bird groups over a 90-year period within the eastern United States using Audubon Christmas Bird Count (CBC) data. We estimated variation in occurrence probability of each group as a function of spatial and temporal variation in winter climate (minimum temperature, cumulative precipitation) and LULC (proportion of group-specific and anthropogenic habitats within CBC circle). We reveal that spatial variation in bird occurrence probability was consistently explained by climate across all nine species groups. Conversely, LULC change explained more than twice the temporal variation (i.e., decadal changes) in bird occurrence probability than climate change on average across groups. This pattern was largely driven by habitat-constrained species (e.g., grassland birds, waterbirds), whereas decadal changes in occurrence probabilities of habitat-unconstrained species (e.g., forest passerines, mixed habitat birds) were equally explained by both climate and LULC changes over the last century. We conclude that climate has generally governed the winter occurrence of avifauna in space and time, while LULC change has played a pivotal role in driving distributional dynamics of species with limited and declining habitat availability. Effective land management will be critical for improving species' resilience to climate change, especially during a season of relative resource scarcity and critical energetic trade-offs.


Asunto(s)
Cambio Climático , Ecosistema , Biodiversidad , Dinámica Poblacional , Estaciones del Año , Estados Unidos
2.
Ecol Appl ; 32(7): e2679, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35588285

RESUMEN

For many avian species, spatial migration patterns remain largely undescribed, especially across hemispheric extents. Recent advancements in tracking technologies and high-resolution species distribution models (i.e., eBird Status and Trends products) provide new insights into migratory bird movements and offer a promising opportunity for integrating independent data sources to describe avian migration. Here, we present a three-stage modeling framework for estimating spatial patterns of avian migration. First, we integrate tracking and band re-encounter data to quantify migratory connectivity, defined as the relative proportions of individuals migrating between breeding and nonbreeding regions. Next, we use estimated connectivity proportions along with eBird occurrence probabilities to produce probabilistic least-cost path (LCP) indices. In a final step, we use generalized additive mixed models (GAMMs) both to evaluate the ability of LCP indices to accurately predict (i.e., as a covariate) observed locations derived from tracking and band re-encounter data sets versus pseudo-absence locations during migratory periods and to create a fully integrated (i.e., eBird occurrence, LCP, and tracking/band re-encounter data) spatial prediction index for mapping species-specific seasonal migrations. To illustrate this approach, we apply this framework to describe seasonal migrations of 12 bird species across the Western Hemisphere during pre- and postbreeding migratory periods (i.e., spring and fall, respectively). We found that including LCP indices with eBird occurrence in GAMMs generally improved the ability to accurately predict observed migratory locations compared to models with eBird occurrence alone. Using three performance metrics, the eBird + LCP model demonstrated equivalent or superior fit relative to the eBird-only model for 22 of 24 species-season GAMMs. In particular, the integrated index filled in spatial gaps for species with over-water movements and those that migrated over land where there were few eBird sightings and, thus, low predictive ability of eBird occurrence probabilities (e.g., Amazonian rainforest in South America). This methodology of combining individual-based seasonal movement data with temporally dynamic species distribution models provides a comprehensive approach to integrating multiple data types to describe broad-scale spatial patterns of animal movement. Further development and customization of this approach will continue to advance knowledge about the full annual cycle and conservation of migratory birds.


Asunto(s)
Migración Animal , Aves , Animales , Estaciones del Año , América del Sur
3.
Proc Natl Acad Sci U S A ; 116(17): 8609-8614, 2019 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-30886097

RESUMEN

Monarch butterflies in eastern North America have declined by 84% on Mexican wintering grounds since the observed peak in 1996. However, coarse-scale population indices from northern US breeding grounds do not show a consistent downward trend. This discrepancy has led to speculation that autumn migration may be a critical limiting period. We address this hypothesis by examining the role of multiscale processes impacting monarchs during autumn, assessed using arrival abundances at all known winter colony sites over a 12-y period (2004-2015). We quantified effects of continental-scale (climate, landscape greenness, and disease) and local-scale (colony habitat quality) drivers of spatiotemporal trends in winter colony sizes. We also included effects of peak summer and migratory population indices. Our results demonstrate that higher summer abundance on northern breeding grounds led to larger winter colonies as did greener autumns, a proxy for increased nectar availability in southern US floral corridors. Colony sizes were also positively correlated with the amount of local dense forest cover and whether they were located within the Monarch Butterfly Biosphere Reserve, but were not influenced by disease rates. Although we demonstrate a demographic link between summer and fine-scale winter population sizes, we also reveal that conditions experienced during, and at the culmination of, autumn migration impact annual dynamics. Monarchs face a growing threat if floral resources and winter habitat availability diminish under climate change. Our study tackles a long-standing gap in the monarch's annual cycle and highlights the importance of evaluating migratory conditions to understand mechanisms governing long-term population trends.


Asunto(s)
Migración Animal/fisiología , Mariposas Diurnas/fisiología , Densidad de Población , Estaciones del Año , Animales , Ecosistema , México , Modelos Biológicos , Dinámica Poblacional , Estados Unidos
4.
JAMA ; 327(20): 1983-1991, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35499852

RESUMEN

Importance: There are limited high-quality, population-level data about the effect of SARS-CoV-2 infection on pregnancy using contemporaneous comparator cohorts. Objectives: To describe maternal and perinatal outcomes associated with SARS-CoV-2 infection in pregnancy and to assess variables associated with severe disease in the pregnant population. Design, Setting, and Participants: CANCOVID-Preg is an observational surveillance program for SARS-CoV-2-affected pregnancies in Canada. This analysis presents exploratory, population-level data from 6 Canadian provinces for the period of March 1, 2020, to October 31, 2021. A total of 6012 pregnant persons with a positive SARS-CoV-2 polymerase chain reaction test result at any time in pregnancy (primarily due to symptomatic presentation) were included and compared with 2 contemporaneous groups including age-matched female individuals with SARS-CoV-2 and unaffected pregnant persons from the pandemic time period. Exposure: SARS-CoV-2 infection during pregnancy. Incident infections in pregnancy were reported to CANCOVID-Preg by participating provinces/territories. Main Outcomes and Measures: Maternal and perinatal outcomes associated with SARS-CoV-2 infection as well as risk factors for severe disease (ie, disease requiring hospitalization, admission to an intensive care unit/critical care unit, and/or oxygen therapy). Results: Among 6012 pregnant individuals with SARS-CoV-2 in Canada (median age, 31 [IQR, 28-35] years), the greatest proportion of cases were diagnosed at 28 to 37 weeks' gestation (35.7%). Non-White individuals were disproportionately represented. Being pregnant was associated with a significantly increased risk of SARS-CoV-2-related hospitalization compared with SARS-CoV-2 cases among all women aged 20 to 49 years in the general population of Canada (7.75% vs 2.93%; relative risk, 2.65 [95% CI, 2.41-2.88]) as well as an increased risk of intensive care unit/critical care unit admission (2.01% vs 0.37%; relative risk, 5.46 [95% CI, 4.50-6.53]). Increasing age, preexisting hypertension, and greater gestational age at diagnosis were significantly associated with worse maternal outcomes. The risk of preterm birth was significantly elevated among SARS-CoV-2-affected pregnancies (11.05% vs 6.76%; relative risk, 1.63 [95% CI, 1.52-1.76]), even in cases of milder disease not requiring hospitalization, compared with unaffected pregnancies during the same time period. Conclusions and Relevance: In this exploratory surveillance study conducted in Canada from March 2020 to October 2021, SARS-CoV-2 infection during pregnancy was significantly associated with increased risk of adverse maternal outcomes and preterm birth.


Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , Adulto , COVID-19/epidemiología , Canadá/epidemiología , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Recién Nacido , Persona de Mediana Edad , Vigilancia de la Población , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Riesgo , SARS-CoV-2
5.
J Anim Ecol ; 90(5): 1165-1176, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33754380

RESUMEN

Together climate and land-use change play a crucial role in determining species distribution and abundance, but measuring the simultaneous impacts of these processes on current and future population trajectories is challenging due to time lags, interactive effects and data limitations. Most approaches that relate multiple global change drivers to population changes have been based on occurrence or count data alone. We leveraged three long-term (1995-2019) datasets to develop a coupled integrated population model-Bayesian population viability analysis (IPM-BPVA) to project future survival and reproductive success for common loons Gavia immer in northern Wisconsin, USA, by explicitly linking vital rates to changes in climate and land use. The winter North Atlantic Oscillation (NAO), a broad-scale climate index, immediately preceding the breeding season and annual changes in developed land cover within breeding areas both had strongly negative influences on adult survival. Local summer rainfall was negatively related to fecundity, though this relationship was mediated by a lagged interaction with the winter NAO, suggesting a compensatory population-level response to climate variability. We compared population viability under 12 future scenarios of annual land-use change, precipitation and NAO conditions. Under all scenarios, the loon population was expected to decline, yet the steepest declines were projected under positive NAO trends, as anticipated with ongoing climate change. Thus, loons breeding in the northern United States are likely to remain affected by climatic processes occurring thousands of miles away in the North Atlantic during the non-breeding period of the annual cycle. Our results reveal that climate and land-use changes are differentially contributing to loon population declines along the southern edge of their breeding range and will continue to do so despite natural compensatory responses. We also demonstrate that concurrent analysis of multiple data types facilitates deeper understanding of the ecological implications of anthropogenic-induced change occurring at multiple spatial scales. Our modelling approach can be used to project demographic responses of populations to varying environmental conditions while accounting for multiple sources of uncertainty, an increasingly pressing need in the face of unprecedented global change.


Asunto(s)
Aves , Cambio Climático , Animales , Teorema de Bayes , Dinámica Poblacional , Reproducción , Estaciones del Año
6.
Conserv Biol ; 35(5): 1484-1495, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33486838

RESUMEN

Evaluation of protected area effectiveness is critical for conservation of biodiversity. Protected areas that prioritize biodiversity conservation are, optimally, located and managed in ways that support relatively large and stable or increasing wildlife populations. Yet evaluating conservation efficacy remains a challenging endeavor. We used an extensive community science data set, eBird, to evaluate the efficacy of protected areas for birds across the Gulf of Mexico and Atlantic coasts of the United States. We modeled trends (2007-2018) for 12 vulnerable waterbirds that use coastal areas during breeding or wintering. We compared two types of protected areas-sites where conservation organizations implemented active stewardship or management or both to reduce human disturbance (hereafter stewardship sites) and local, state, federal, and private protected areas managed to maintain natural land cover (hereafter protected areas)-as well as unprotected areas. We evaluated differences in trends between stewardship, protected, and unprotected areas across the Gulf and Atlantic coasts as a whole. Similar to a background sample, stewardship was known to occur at stewardship sites, but unknown at protected and unprotected areas. Four of 12 target species-Black Skimmer (Rynchops niger), Brown Pelican (Pelecanus occidentalis), Least Tern (Sternula antillarum), and Piping Plover (Charadrius melodus)-had more positive trends (two to 34 times greater) at stewardship sites than protected areas. Furthermore, five target species showed more positive trends at sites with stewardship programs than unprotected sites during at least one season, whereas seven species showed more positive trends at protected than unprotected areas. No species had more negative trends at stewardship sites than unprotected areas, and two species had more negative trends at protected than unprotected areas. Anthropogenic disturbance is a serious threat to coastal birds, and our findings demonstrate that stewardship to reduce its negative impacts helps ensure conservation of vulnerable waterbirds.


La evaluación de la efectividad de las áreas protegidas es de suma importancia para la conservación de la biodiversidad. Las áreas protegidas que priorizan la conservación de la biodiversidad están, de manera óptima, ubicadas y manejadas de maneras que permiten el mantenimiento de poblaciones silvestres relativamente grandes y estables o en incremento. Aun así, la evaluación de la eficacia de la conservación todavía es un esfuerzo desafiante. Usamos un conjunto extensivo de datos de ciencia comunitaria, eBird, para evaluar la eficacia de las áreas protegidas a lo largo de las costas del Golfo de México y del Atlántico en los Estados Unidos. Modelamos las tendencias poblacionales (2007-2018) para doce aves acuáticas vulnerables que usan las áreas costeras durante la temporada de reproducción o de hibernación. Comparamos dos tipos de áreas protegidas - sitios en donde las organizaciones de conservación implementaron una gestión o manejo activo o ambos para reducir la perturbación humana (de ahora en adelante sitios de gestión) y las áreas protegidas locales, estatales, federales y privadas manejadas para mantener la cobertura natural del suelo (de ahora en adelante áreas protegidas) - así como las áreas desprotegidas. Evaluamos las diferencias en las tendencias entre las áreas de gestión, las protegidas y las desprotegidas a lo largo de las cosas del Golfo y del Atlántico como un todo. Similar a una muestra de fondo, se supo que la gestión ocurría en los sitios de gestión, pero no se sabía si ocurría en las áreas protegidas y desprotegidas. Cuatro de las doce especies analizadas - Rhynchops niger, Pelecanus occidentalis, Sternula antillarum y Charadrius melodus - tuvieron tendencias más positivas (2-34 veces mayor) en los sitios de gestión que en las áreas protegidas. Además, cinco especies mostraron más tendencias positivas en los sitios con programas de gestión que en los sitios desprotegidos al menos durante una temporada, mientras que siete especies mostraron más tendencias positivas en sitios protegidos que en las áreas desprotegidas. protegidas que en las desprotegidas. Ninguna especie tuvo más tendencias negativas en los sitios de gestión que en las áreas desprotegidas y dos especies tuvieron más tendencias negativas en las áreas protegidas que en las desprotegidas. La perturbación antropogénica es una amenaza seria para las aves costeras y nuestros hallazgos demuestran que la gestión para reducir sus impactos negativos ayuda a asegurar la conservación de aves acuáticas vulnerables.


Asunto(s)
Aves , Conservación de los Recursos Naturales , Animales , Biodiversidad , Cruzamiento , Humanos
7.
Lab Invest ; 100(8): 1102-1110, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32203151

RESUMEN

Biological materials presenting early signs of cancer would be beneficial for cancer screening/diagnosis. In this respect, the suitability of potentially exploiting mucus in colorectal cancer was tested using infrared spectroscopy in combination with statistical modeling. Twenty-six paraffinized colon tissue biopsy sections containing mucus regions from 20 individuals (10 normal and 16 cancerous) were measured using mid-infrared spectroscopic imaging. A digital de-paraffinization, followed by cluster analysis driven digital color-coded multi-staining segmented the infrared images into various histopathological features such as epithelium, connective tissue, stroma, and mucus regions within the tissue sections. Principal component analysis followed by supervised linear discriminant analysis was carried out on pure mucus and epithelial spectra from normal and cancerous regions of the tissue. For the mucus-based classification, a sensitivity of 96%, a specificity of 83%, and an area under the curve performance of 95% was obtained. For the epithelial tissue-based classification, a sensitivity of 72%, a specificity of 88%, and an area under the curve performance of 89% was obtained. The mucus spectral profiles further showed contributions indicative of glycans including that of sialic acid changes between these pathology groups. The study demonstrates that infrared spectroscopic analysis of mucus discriminates colorectal cancers with high sensitivity. This concept could be exploited to develop screening/diagnostic approaches complementary to histopathology.


Asunto(s)
Neoplasias del Colon/diagnóstico , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/métodos , Moco/metabolismo , Espectrofotometría Infrarroja/métodos , Análisis por Conglomerados , Colon/metabolismo , Colon/patología , Neoplasias del Colon/metabolismo , Neoplasias Colorrectales/metabolismo , Análisis Discriminante , Humanos , Intestinos/química , Intestinos/patología , Ácido N-Acetilneuramínico/metabolismo , Polisacáridos/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Ecol Appl ; 30(6): e02128, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32223029

RESUMEN

Climate change poses an intensifying threat to many bird species and projections of future climate suitability provide insight into how species may shift their distributions in response. Climate suitability is characterized using ecological niche models (ENMs), which correlate species occurrence data with current environmental covariates and project future distributions using the modeled relationships together with climate predictions. Despite their widespread adoption, ENMs rely on several assumptions that are rarely validated in situ and can be highly sensitive to modeling decisions, precluding their reliability in conservation decision-making. Using data from a novel, large-scale community science program, we developed dynamic occupancy models to validate near-term climate suitability projections for bluebirds and nuthatches in summer and winter. We estimated occupancy, colonization, and extinction dynamics across species' ranges in the United States in relation to projected climate suitability in the 2020s, and used a Gibbs variable selection approach to quantify evidence of species-climate relationships. We also included a Bird Conservation Region strata-level random effect to examine among-strata variation in occupancy that may be attributable to land-use and ecoregional differences. Across species and seasons, we found strong evidence that initial occupancy and colonization were positively related to 2020 climate suitability, illustrating an independent validation of projections from ENMs across a large geographic area. Random strata effects revealed that occupancy probabilities were generally higher than average in core areas and lower than average in peripheral areas of species' ranges, and served as a first step in identifying spatial patterns of occupancy from these community science data. Our findings lend much-needed support to the use of ENM projections for addressing questions about potential climate-induced changes in species' occupancy dynamics. More broadly, our work highlights the value of community scientist observations for ground-truthing projections from statistical models and for refining our understanding of the processes shaping species' distributions under a changing climate.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Aves , Modelos Teóricos , Reproducibilidad de los Resultados , Estados Unidos
9.
Lancet ; 390(10090): 145-154, 2017 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-28551075

RESUMEN

BACKGROUND: England and Wales have one of the highest frequencies of autopsy in the world. Implementation of post-mortem CT (PMCT), enhanced with targeted coronary angiography (PMCTA), in adults to avoid invasive autopsy would have cultural, religious, and potential economic benefits. We aimed to assess the diagnostic accuracy of PMCTA as a first-line technique in post-mortem investigations. METHODS: In this single-centre (Leicester, UK), prospective, controlled study, we selected cases of natural and non-suspicious unnatural death referred to Her Majesty's (HM) Coroners. We excluded cases younger than 18 years, known to have had a transmittable disease, or who weighed more than 125 kg. Each case was assessed by PMCTA, followed by autopsy. Pathologists were masked to the PMCTA findings, unless a potential risk was shown. The primary endpoint was the accuracy of the cause of death diagnosis from PMCTA against a gold standard of autopsy findings, modified by PMCTA findings only if additional substantially incontrovertible findings were identified. FINDINGS: Between Jan 20, 2010, and Sept 13, 2012, we selected 241 cases, for which PMCTA was successful in 204 (85%). Seven cases were excluded from the analysis because of procedural unmasking or no autopsy data, as were 24 cases with a clear diagnosis of traumatic death before investigation; 210 cases were included. In 40 (19%) cases, predictable toxicology or histology testing accessible by PMCT informed the result. PMCTA provided a cause of death in 193 (92%) cases. A major discrepancy with the gold standard was noted in 12 (6%) cases identified by PMCTA, and in nine (5%) cases identified by autopsy (because of specific findings on PMCTA). The frequency of autopsy and PMCTA discrepancies were not significantly different (p=0·65 for major discrepancies and p=0·21 for minor discrepancies). Cause of death given by PMCTA did not overlook clinically significant trauma, occupational lung disease, or reportable disease, and did not significantly affect the overall population data for cause of death (p≥0·31). PMCTA was better at identifying trauma and haemorrhage (p=0·008), whereas autopsy was better at identifying pulmonary thromboembolism (p=0·004). INTERPRETATION: For most sudden natural adult deaths investigated by HM Coroners, PMCTA could be used to avoid invasive autopsy. The gold standard of post-mortem investigations should include both PMCT and invasive autopsy. FUNDING: National Institute for Health Research.


Asunto(s)
Autopsia/métodos , Muerte Súbita/etiología , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Hemorragia Cerebral/diagnóstico por imagen , Angiografía Coronaria , Médicos Forenses , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Estudios Prospectivos , Adulto Joven
10.
J Obstet Gynaecol Can ; 39(8): 668-675, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28729100

RESUMEN

OBJECTIVE: This study was conducted to evaluate the roll-out of rapid HIV testing as part of an emergency Prevention of Perinatal HIV Transmission Program. Specifically, HIV prevalence in this population, the reason(s) for performing the rapid HIV test, and compliance with recommendations for antiretroviral prophylaxis were assessed. METHODS: Since November 2011, all women presenting to a tertiary labour and delivery unit with unknown HIV status or with ongoing risk of HIV infection since their last HIV test were offered rapid HIV testing. Through retrospective chart review, demographic data, HIV risk and prior testing history, and antiretroviral prophylaxis, data were collected and descriptive statistics were performed. RESULTS: One hundred fourteen rapid HIV tests were conducted and there were two preliminary reactive rapid results (one true positive, one false positive). None of the infants was HIV infected. Sixty-three percent of women had multiple risk factors for HIV acquisition, most commonly intravenous drug use (54%). Forty-four percent of women were within the 4-week seroconversion window at the time of delivery; 25% of these women and 52% of their infants received prophylactic drug therapy. CONCLUSION: Rapid HIV testing identified a high-risk cohort and enabled aggressive management of a newly diagnosed HIV-positive pregnancy, successfully preventing perinatal HIV transmission. Risk factors for HIV acquisition were ongoing within the seroconversion window for over half of the women, impacting the utility of the test in eliminating unnecessary antiretroviral prophylaxis in this population because prophylaxis is recommended despite a negative rapid HIV test in these cases.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/diagnóstico , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Atención Perinatal/métodos , Complicaciones Infecciosas del Embarazo/diagnóstico , Adolescente , Adulto , Quimioprevención , Reacciones Falso Positivas , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Humanos , Recién Nacido , Masculino , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Medición de Riesgo , Abuso de Sustancias por Vía Intravenosa , Factores de Tiempo , Adulto Joven
11.
Ecology ; 97(12): 3300-3307, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27912019

RESUMEN

Occupancy modeling is a widely used analytical technique for assessing species distributions and range dynamics. However, occupancy analyses frequently ignore variation in abundance of occupied sites, even though site abundances affect many of the parameters being estimated (e.g., extinction, colonization, detection probability). We introduce a new model ("dynamic N-occupancy") capable of providing accurate estimates of local abundance, population gains (reproduction/immigration), and apparent survival probabilities while accounting for imperfect detection using only detection/nondetection data. Our model utilizes heterogeneity in detection based on variations in site abundances to estimate latent demographic rates via a dynamic N-mixture modeling framework. We validate our model using simulations across a wide range of values and examine the data requirements, including the number of years and survey sites needed, for unbiased and precise estimation of parameters. We apply our model to estimate spatiotemporal heterogeneity in abundances of barred owls (Strix varia) within a recently invaded region in Oregon (USA). Estimates of apparent survival and population gains are consistent with those from a nearby radio-tracking study and elucidate how barred owl abundances have increased dramatically over time. The dynamic N-occupancy model greatly improves inferences on individual-level population processes from occupancy data by explicitly modeling the latent population structure.


Asunto(s)
Ecosistema , Modelos Biológicos , Estrigiformes/fisiología , Animales , Dinámica Poblacional
12.
14.
BMC Musculoskelet Disord ; 17(1): 461, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27829394

RESUMEN

BACKGROUND: The Scottish Early Rheumatoid Arthritis (SERA) study is an inception cohort of rheumatoid (RA) and undifferentiated arthritis (UA) patients that aims to provide a contemporary description of phenotype and outcome and facilitate discovery of phenotypic and prognostic biomarkers METHODS: Demographic and clinical outcome data are collected from newly diagnosed RA/UA patients every 6 months from around Scotland. Health service utilization data is acquired from Information Services Division, NHS National Services Scotland. Plain radiographs of hands and feet are collected at baseline and 12 months. Additional samples of whole blood, plasma, serum and filtered urine are collected at baseline, 6 and 12 months RESULTS: Results are available for 1073 patients; at baseline, 76 % were classified as RA and 24 % as UA. Median time from onset to first review was 163 days (IQR97-323). Methotrexate was first-line DMARD for 75 % patients. Disease activity, functional ability and health-related quality of life improved significantly between baseline and 24 months, however the proportion in any employment fell (51 to 38 %, p = 0.0005). 24 % patients reported symptoms of anxiety and/or depression at baseline. 35/391 (9 %) patients exhibited rapid radiographic progression after 12 months. The SERA Biobank has accrued 60,612 samples CONCLUSIONS: In routine care, newly diagnosed RA/UA patients experience significant improvements in disease activity, functional ability and health-related quality of life but have high rates of psychiatric symptoms and declining employment rates. The co-existence of a multi-domain description of phenotype and a comprehensive biobank will facilitate multi-platform translational research to identify predictive markers of phenotype and prognosis.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/sangre , Bancos de Muestras Biológicas , Aceptación de la Atención de Salud/estadística & datos numéricos , Anciano , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/psicología , Biomarcadores/sangre , Biomarcadores/orina , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Pie/diagnóstico por imagen , Mano/diagnóstico por imagen , Humanos , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Medicina de Precisión , Pronóstico , Calidad de Vida , Radiografía , Escocia , Índice de Severidad de la Enfermedad , Manejo de Especímenes , Investigación Biomédica Traslacional
16.
Int J Legal Med ; 126(3): 461-5, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22008786

RESUMEN

We report a case of a 4-year-old child found dead at his home inside a domestic clothes (tumble) dryer. The child had been reported missing in the morning by his mother and found a short time later inside the dryer with the door shut. The child was pronounced dead at the scene. A pre-autopsy computed tomography scan identified findings associated with aggressive resuscitation attempts. Post-mortem examination showed generalised blunt trauma to his head and limbs, a thin film subdural haemorrhage and burns from contact with hot components and hot air whilst being trapped alive inside the active dryer. A forensic examination of the dryer revealed that it was possible for the child to become trapped in the dryer by his own action and that the dryer could operate for sufficient time to allow for the causation of the injuries to the child. A review of the medical literature and media reports of deaths related to clothes dryer, injuries sustained to survivors and use of dryers as a body disposal site is presented.


Asunto(s)
Accidentes Domésticos , Quemaduras/patología , Heridas no Penetrantes/patología , Reanimación Cardiopulmonar/efectos adversos , Preescolar , Diseño de Equipo , Patologia Forense , Hematoma Subdural/patología , Humanos , Masculino , Tomografía Computarizada Multidetector , Neumoperitoneo/diagnóstico por imagen , Neumoperitoneo/etiología , Neumotórax/diagnóstico por imagen , Neumotórax/etiología , Púrpura/patología
17.
Am J Forensic Med Pathol ; 33(3): 276-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21030848

RESUMEN

We present a case of a 30-year-old woman with learning difficulties who was found dead at home by her mother. Her body was partially naked and covered in a number of unusual skin lesions with a targetoid appearance with red erythematous centers and well-delineated halos of pallor. These lesions were initially thought to be bruises by the police and by a forensic postmortem instigated. Postmortem examination also identified hepatosplenomegaly, severe lymphadenopathy, and focal patchy colonic ulceration. Histologic examination of the skin and bowel ulcers showed the lesions to be areas of infarction caused by Pseudomonas aeruginosa vasculitis. Pseudomonas was also cultured from the swabs of the abdomen, the spleen, and the blood cultures. Histologic findings of the lymph nodes showed complete effacement of the normal architecture by a population of pleomorphic small lymphoid cells. Immunohistochemistry confirmed the predominant cell type to be T-cells. The diagnosis of peripheral T-cell lymphoma was made. The cause of death was given as Pseudomonas septicemia secondary to immunocompromise resulting from the undiagnosed peripheral T-cell lymphoma. The pathogenesis of Pseudomonas and its association with malignancy is discussed along with a brief review of peripheral T-cell lymphomas. This case report demonstrates the characteristic macroscopic appearance of cutaneous Pseudomonas-associated lesions and how they can be misinterpreted as bruises.


Asunto(s)
Eritema Nudoso/etiología , Linfoma de Células T Periférico/diagnóstico , Infecciones por Pseudomonas/diagnóstico , Sepsis/diagnóstico , Adulto , Enfermedades del Ano/patología , Contusiones/diagnóstico , Diagnóstico Diferencial , Errores Diagnósticos , Eritema Nudoso/diagnóstico , Femenino , Patologia Forense , Humanos , Huésped Inmunocomprometido , Enfermedades Intestinales/patología , Linfoma de Células T Periférico/complicaciones , Sepsis/microbiología , Úlcera Cutánea/patología , Úlcera/patología , Vasculitis/microbiología , Vasculitis/patología
18.
Forensic Sci Med Pathol ; 8(1): 40-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21811877

RESUMEN

With the introduction of targeted coronary artery angiography to post-mortem computed tomography (PMCT) it is now possible to assess the coronary arteries and left ventricle after death without, case dependent, the necessity to undertake an invasive autopsy. The purpose of this pictorial review is to act as a walk through aid memoire and educational learning document for radiologists and pathologists alike who may be new to the use and interpretation of targeted PMCT angiography. By using an example scanning protocol, which uses both positive and negative (air) contrast mediums, this pictorial review provides a systematic approach to vessel and ventricular assessment that is based upon clinical cardiac angiography but adapted to PMCT.


Asunto(s)
Autopsia/métodos , Angiografía Coronaria/métodos , Tomografía Computarizada por Rayos X , Aire , Cardiomiopatías/diagnóstico por imagen , Cateterismo , Catéteres , Medios de Contraste , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Patologia Forense , Corazón/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Cambios Post Mortem , Arteria Pulmonar/diagnóstico por imagen , Stents , Grado de Desobstrucción Vascular
19.
Appl Sci (Basel) ; 12(8)2022 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-36911244

RESUMEN

Inverse modeling approaches in cardiovascular medicine are a collection of methodologies that can provide non-invasive patient-specific estimations of tissue properties, mechanical loads, and other mechanics-based risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs. These methods have become available for medical applications mainly due to the continuing development of image-based kinematic techniques, the maturity of the associated theories describing cardiovascular function, and recent progress in computer science, modeling, and simulation engineering. Inverse method applications are multidisciplinary, requiring tailored solutions to the available clinical data, pathology of interest, and available computational resources. Herein, we review biomechanical modeling and simulation principles, methods of solving inverse problems, and techniques for image-based kinematic analysis. In the final section, the major advances in inverse modeling of human cardiovascular mechanics since its early development in the early 2000s are reviewed with emphasis on method-specific descriptions, results, and conclusions. We draw selected studies on healthy and diseased hearts, aortas, and pulmonary arteries achieved through the incorporation of tissue mechanics, hemodynamics, and fluid-structure interaction methods paired with patient-specific data acquired with medical imaging in inverse modeling approaches.

20.
PLoS One ; 17(6): e0269499, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35709083

RESUMEN

Tissue engineering commonly entails combining autologous cell sources with biocompatible scaffolds for the replacement of damaged tissues in the body. Scaffolds provide functional support while also providing an ideal environment for the growth of new tissues until host integration is complete. To expedite tissue development, cells need to be distributed evenly within the scaffold. For scaffolds with a small diameter tubular geometry, like those used for vascular tissue engineering, seeding cells evenly along the luminal surface can be especially challenging. Perfusion-based cell seeding methods have been shown to promote increased uniformity in initial cell distribution onto porous scaffolds for a variety of tissue engineering applications. We investigate the seeding efficiency of a custom-designed perfusion-based seed-and-culture bioreactor through comparisons to a static injection counterpart method and a more traditional drip seeding method. Murine vascular smooth muscle cells were seeded onto porous tubular electrospun polycaprolactone scaffolds, 2 mm in diameter and 30 mm in length, using the three methods, and allowed to rest for 24 hours. Once harvested, scaffolds were evaluated longitudinally and circumferentially to assess the presence of viable cells using alamarBlue and live/dead cell assays and their distribution with immunohistochemistry and scanning electron microscopy. On average, bioreactor-mediated perfusion seeding achieved 35% more luminal surface coverage when compared to static methods. Viability assessment demonstrated that the total number of viable cells achieved across methods was comparable with slight advantage to the bioreactor-mediated perfusion-seeding method. The method described is a simple, low-cost method to consistently obtain even distribution of seeded cells onto the luminal surfaces of small diameter tubular scaffolds.


Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Animales , Reactores Biológicos , Prótesis Vascular , Células Cultivadas , Ratones , Perfusión , Ingeniería de Tejidos/métodos
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