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1.
Conserv Biol ; 36(6): e13934, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35561029

RESUMO

Effective conservation requires understanding species' abundance patterns and demographic rates across space and time. Ideally, such knowledge should be available for whole communities because variation in species' dynamics can elucidate factors leading to biodiversity losses. However, collecting data to simultaneously estimate abundance and demographic rates of communities of species is often prohibitively time intensive and expensive. We developed a multispecies dynamic N-occupancy model to estimate unbiased, community-wide relative abundance and demographic rates. In this model, detection-nondetection data (e.g., repeated presence-absence surveys) are used to estimate species- and community-level parameters and the effects of environmental factors. To validate our model, we conducted a simulation study to determine how and when such an approach can be valuable and found that our multispecies model outperformed comparable single-species models in estimating abundance and demographic rates in many cases. Using data from a network of camera traps across tropical equatorial Africa, we then used our model to evaluate the statuses and trends of a forest-dwelling antelope community. We estimated relative abundance, rates of recruitment (i.e., reproduction and immigration), and apparent survival probabilities for each species' local population. The antelope community was fairly stable (although 17% of populations [species-park combinations] declined over the study period). Variation in apparent survival was linked more closely to differences among national parks than to individual species' life histories. The multispecies dynamic N-occupancy model requires only detection-nondetection data to evaluate the population dynamics of multiple sympatric species and can thus be a valuable tool for examining the reasons behind recent biodiversity loss.


La conservación efectiva requiere del entendimiento de los patrones de abundancia de las especies a lo largo del tiempo y el espacio. Sería ideal que dicho conocimiento estuviera disponible para todas las comunidades ya que la variación en la dinámica de las especies puede esclarecer los factores que llevan a la pérdida de la biodiversidad. Sin embargo, la recolección de información para estimar simultáneamente las tasas demográficas y de abundancia de las comunidades de especies con frecuencia es cara y consume tiempo. Desarrollamos un modelo multiespecies dinámico de ocupación-N para estimar la tasa demográfica y de abundancia relativas sin sesgos y en toda la comunidad. En este modelo usamos información de detección-no detección (p. ej.: censos repetidos de presencia-ausencia) para estimar los parámetros a nivel comunitario y de especie y los efectos de los factores ambientales. Para validar nuestro modelo, realizamos un estudio de simulación para determinar cómo y cuándo dicha estrategia puede ser valiosa y descubrimos que nuestro modelo multiespecies superó a los modelos comparables de una sola especie en la estimación de las tasas demográficas y de abundancia en muchos casos. Usamos nuestro modelo con datos de una red de cámaras trampa ubicadas a lo largo de África ecuatorial para evaluar los estados y tendencias de una comunidad forestal de antílopes. Estimamos la abundancia relativa, tasa de reclutamiento (es decir, reproducción e inmigración) y las probabilidades de supervivencia aparente para la población local de cada especie. La comunidad de antílopes fue bastante estable (aunque el 17% de las poblaciones [combinaciones especie-parque] declinaron durante el periodo de estudio). La variación en la supervivencia aparente estuvo vinculada con mayor cercanía a las diferencias entre los parques nacionales que a la historia de vida de cada especie individual. El modelo multiespecies dinámico de ocupación-N requiere solamente información de detección-no detección para evaluar las dinámicas poblacionales de muchas especies simpátricas y por lo tanto puede ser una herramienta valiosa para examinar las razones detrás de la pérdida reciente de la biodiversidad.


Assuntos
Antílopes , Conservação dos Recursos Naturais , Animais , Animais Selvagens , Dinâmica Populacional , Biodiversidade
2.
J Anim Ecol ; 90(5): 1165-1176, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33754380

RESUMO

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.


Assuntos
Aves , Mudança Climática , Animais , Teorema de Bayes , Dinâmica Populacional , Reprodução , Estações do Ano
3.
Oecologia ; 196(3): 707-721, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34143262

RESUMO

Understanding of animal responses to dynamic resource landscapes is based largely on research on temperate species with small body sizes and fast life histories. We studied a large, tropical mammal with an extremely slow life history, the Western Bornean orangutan (Pongo pygmaeus wurmbii), across a heterogeneous natural landscape encompassing seven distinct forest types. Our goals were to characterize fluctuations in abundance, test hypotheses regarding the relationship between dispersion dynamics and resource availability, and evaluate how movement patterns are influenced by abiotic conditions. We surveyed abundance in Gunung Palung National Park, West Kalimantan, Indonesia, for 99 consecutive months and simultaneously recorded weather data and assessed fruit availability. We developed a Bayesian hierarchical distance sampling model to estimate population dispersion and assess the roles of fruit availability, rainfall, and temperature in driving movement patterns across this heterogeneous landscape. Orangutan abundance varied dramatically over space and time. Each forest type was important in sustaining more than 40% of the total orangutans on site during at least one month, as animals moved to track asynchronies in fruiting phenology. We conclude that landscape-level movements buffer orangutans against fruit scarcity, peat swamps are crucial fallback habitats, and orangutans' use of high elevation forests is strongly dependent on abiotic conditions. Our results show that orangutans can periodically occupy putative-sink habitats and be virtually absent for extended periods from habitats that are vitally important in sustaining their population, highlighting the need for long-term studies and potential risks in interpreting occurrence or abundance measures as indicators of habitat importance.


Assuntos
Pongo pygmaeus , Pongo , Animais , Teorema de Bayes , Ecossistema , Indonésia
4.
Ecol Appl ; 29(2): e01845, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30694574

RESUMO

Carnivore communities face unprecedented threats from humans. Yet, management regimes have variable effects on carnivores, where species may persist or decline in response to direct or indirect changes to the ecosystem. Using a hierarchical multispecies modeling approach, we examined the effects of alternative management regimes (i.e., active vs. passive enforcement of regulations) on carnivore abundances and group sizes at both species and community levels in the Masai Mara National Reserve, Kenya. Alternative management regimes have created a dichotomy in ecosystem conditions within the Reserve, where active enforcement of regulations maintains low levels of human disturbance in the Mara Triangle and passive enforcement of regulations in the Talek region permits multiple forms of human disturbance. Our results demonstrate that these alternative management regimes have variable effects on 11 observed carnivore species. As predicted, some species, such as African lions and bat-eared foxes, have higher population densities in the Mara Triangle, where regulations are actively enforced. Yet, other species, including black-backed jackals and spotted hyenas, have higher population densities in the Talek region where enforcement is passive. Multiple underlying mechanisms, including behavioral plasticity and competitive release, are likely causing higher black-backed jackals and spotted hyena densities in the disturbed Talek region. Our multispecies modeling framework reveals that carnivores do not react to management regimes uniformly, shaping carnivore communities by differentially producing winning and losing species. Some carnivore species require active enforcement of regulations for effective conservation, while others more readily adapt (and in some instances thrive in response) to lax management enforcement and resulting anthropogenic disturbance. Yet, high levels of human disturbance appear to be negatively affecting the majority of carnivores, with potential consequences that may permeate throughout the rest of the ecosystem. Community approaches to monitoring carnivores should be adopted as single species monitoring may overlook important intra-community variability.


Assuntos
Carnívoros , Ecossistema , Animais , Humanos , Quênia , Densidade Demográfica
5.
Cochrane Database Syst Rev ; 3: CD009868, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28263370

RESUMO

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of death and disability worldwide, yet ASCVD risk factor control and secondary prevention rates remain low. A fixed-dose combination of blood pressure- and cholesterol-lowering and antiplatelet treatments into a single pill, or polypill, has been proposed as one strategy to reduce the global burden of ASCVD. OBJECTIVES: To determine the effect of fixed-dose combination therapy on all-cause mortality, fatal and non-fatal ASCVD events, and adverse events. We also sought to determine the effect of fixed-dose combination therapy on blood pressure, lipids, adherence, discontinuation rates, health-related quality of life, and costs. SEARCH METHODS: We updated our previous searches in September 2016 of CENTRAL, MEDLINE, Embase, ISI Web of Science, and DARE, HTA, and HEED. We also searched two clinical trials registers in September 2016. We used no language restrictions. SELECTION CRITERIA: We included randomised controlled trials of a fixed-dose combination therapy including at least one blood pressure-lowering and one lipid-lowering component versus usual care, placebo, or an active drug comparator for any treatment duration in adults 18 years old or older, with no restrictions on presence or absence of pre-existing ASCVD. DATA COLLECTION AND ANALYSIS: Three review authors independently selected studies for inclusion and extracted the data for this update. We evaluated risk of bias using the Cochrane 'Risk of bias' assessment tool. We calculated risk ratios (RR) for dichotomous data and mean differences (MD) for continuous data with 95% confidence intervals (CI) using fixed-effect models when heterogeneity was low (I2 < 50%) and random-effects models when heterogeneity was high (I2 ≥ 50%). We used the GRADE approach to evaluate the quality of evidence. MAIN RESULTS: In the initial review, we identified nine randomised controlled trials with a total of 7047 participants and four additional trials (n = 2012 participants; mean age range 62 to 63 years; 30% to 37% women) were included in this update. Eight of the 13 trials evaluated the effects of fixed-dose combination (FDC) therapy in populations without prevalent ASCVD, and the median follow-up ranged from six weeks to 23 months. More recent trials were generally larger with longer follow-up and lower risk of bias. The main risk of bias was related to lack of blinding of participants and personnel, which was inherent to the intervention. Compared with the comparator groups (placebo, usual care, or active drug comparator), the effects of the fixed-dose combination treatment on mortality (FDC = 1.0% versus control = 1.0%, RR 1.10, 95% CI 0.64 to 1.89,  I2 = 0%, 5 studies, N = 5300) and fatal and non-fatal ASCVD events (FDC = 4.7% versus control = 3.7%, RR 1.26, 95% CI 0.95 to 1.66, I2 = 0%, 6 studies, N = 4517) were uncertain (low-quality evidence). The low event rates for these outcomes and indirectness of evidence for comparing fixed-dose combination to usual care versus individual drugs suggest that these results should be viewed with caution. Adverse events were common in both the intervention (32%) and comparator (27%) groups, with participants randomised to fixed-dose combination therapy being 16% (RR 1.16, 95% CI 1.09 to 1.25, 11 studies, 6906 participants, moderate-quality evidence) more likely to report an adverse event . The mean differences in systolic blood pressure between the intervention and control arms was -6.34 mmHg (95% CI -9.03 to -3.64, 13 trials, 7638 participants, moderate-quality evidence). The mean differences (95% CI) in total and LDL cholesterol between the intervention and control arms were -0.61 mmol/L (95% CI -0.88 to -0.35, 11 trials, 6565 participants, low-quality evidence) and -0.70 mmol/L (95% CI -0.98 to -0.41, 12 trials, 7153 participants, moderate-quality evidence), respectively. There was a high degree of statistical heterogeneity in comparisons of blood pressure and lipids (I2 ≥ 80% for all) that could not be explained, so these results should be viewed with caution. Fixed-dose combination therapy improved adherence to a multidrug strategy by 44% (26% to 65%) compared with usual care (4 trials, 3835 participants, moderate-quality evidence). AUTHORS' CONCLUSIONS: The effects of fixed-dose combination therapy on all-cause mortality or ASCVD events are uncertain. A limited number of trials reported these outcomes, and the included trials were primarily designed to observe changes in ASCVD risk factor levels rather than clinical events, which may partially explain the observed differences in risk factors that were not translated into differences in clinical outcomes among the included trials. Fixed-dose combination therapy is associated with modest increases in adverse events compared with placebo, active comparator, or usual care but may be associated with improved adherence to a multidrug regimen. Ongoing, longer-term trials of fixed-dose combination therapy will help demonstrate whether short-term changes in risk factors might be maintained and lead to expected differences in clinical events based on these changes.


Assuntos
Anticolesterolemiantes/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Aspirina/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Inibidores da Agregação Plaquetária/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Aspirina/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/mortalidade , Causas de Morte , Colesterol/sangue , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Inibidores da Agregação Plaquetária/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Artigo em Inglês | MEDLINE | ID: mdl-27733813

RESUMO

BACKGROUND: Bone conduction devices are widely used and indicated in cases of conductive, mixed or single sided deafness where conventional hearing aids are not indicated or tolerated. Percutaneous bone-conduction devices gave satisfactory hearing outcomes but were frequently complicated by soft tissue reactions. Transcutaneous bone conduction devices were developed in order to address some of the issues related to the skin-penetrating abutment. The aim of this article is to present a systematic review of the indications, surgical technique and audiological, clinical and functional outcomes of the BAHA Attract device reported so far. METHODS: A systematic computer-based literature search was performed on the PubMed database as well as Scopus, Cochrane and Google Scholar. Out of 497 articles, 10 studies and 89 reported cases were finally included in our review. RESULTS: The vast majority of implanted patients were satisfied with the aesthetics of the device scoring highly at the Abbreviated Profile of Hearing Aid Benefit, Glasgow Benefit Inventory and Client Oriented Scale of Improvement. Overall, hearing outcomes, tested by various means including speech in noise, free field hearing testing and word discrimination scores showed a significant improvement. Complications included seroma or haematoma formation, numbness around the area of the flap, swelling and detachment of the sound processor from the external magnet. CONCLUSIONS: The functional and audiological results presented so far in the literature have been satisfactory and the complication rate is low compared to the skin penetrating Bone Conduction Devices. Further robust trials will be needed to study the long-term outcomes and any adverse effects.

7.
Cochrane Database Syst Rev ; (4): CD009868, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24737108

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death and disability worldwide, yet CVD risk factor control and secondary prevention rates remain low. A fixed-dose combination of blood pressure and cholesterol lowering and antiplatelet treatments into a single pill, or polypill, has been proposed as one strategy to reduce the global burden of CVD by up to 80% given its potential for better adherence and lower costs. OBJECTIVES: To determine the effectiveness of fixed-dose combination therapy on reducing fatal and non-fatal CVD events and on improving blood pressure and lipid CVD risk factors for both primary and secondary prevention of CVD. We also aimed to determine discontinuation rates, adverse events, health-related quality of life, and costs of fixed-dose combination therapy. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2013, Issue 6), MEDLINE Ovid (1946 to week 2 July 2013), EMBASE Ovid (1980 to Week 28 2013), ISI Web of Science (1970 to 19 July 2013), and the Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTA), and Health Economics Evaluations Database (HEED) (2011, Issue 4) in The Cochrane Library. We used no language restrictions. SELECTION CRITERIA: We included randomised controlled trials of a fixed-dose combination therapy including at least one blood pressure lowering and one lipid lowering component versus usual care, placebo, or a single drug active component for any treatment duration in adults ≥ 18 years old with no restrictions on presence or absence of pre-existing cardiovascular disease. DATA COLLECTION AND ANALYSIS: Three review authors independently selected studies for inclusion and extracted the data. We evaluated risk of bias using the Cochrane risk of bias assessment tool. We sought to include outcome data on all-cause mortality, fatal and non-fatal CVD events, adverse events, changes in systolic and diastolic blood pressure, total and low density lipoprotein (LDL) cholesterol concentrations, discontinuation rates, quality of life, and costs. We calculated risk ratios (RR) for dichotomous data and weighted mean differences (MD) for continuous data with 95% confidence intervals (CI) using fixed-effect models when heterogeneity was low (I(2) < 50%) and random-effects models when heterogeneity was high (I(2) > 50%). MAIN RESULTS: We found nine randomised controlled trials with a total of 7047 participants. Seven of the nine trials evaluated the effects of fixed-dose combination therapy on primary CVD prevention, and the trial length ranged from six weeks to 15 months. We found a moderate to high risk of bias in the domains of selection, performance, detection, attrition, and other types of bias in five of the nine trials. Compared with the comparator groups, the effects of the fixed-dose combination treatment on mortality (1.2% versus 1.0%, RR 1.26, 95% CI 0.67 to 2.38,  N = 3465) and cardiovascular events (4.0% versus 2.9%, RR 1.38, 95% CI 0.91 to 2.10, N = 2479) were uncertain (low quality evidence). The low event rates for these outcomes, limited availability of data as only two out of nine trials reported on these outcomes, and a high risk of bias in at least one domain suggest that these results should not be viewed with confidence. Adverse events were common in both the intervention (30%) and comparator (24%) groups, with participants randomised to fixed-dose combination therapy being 20% (95% CI 9% to 30%) more likely to report an adverse event. Notably, no serious adverse events were reported. Compared with placebo, the rate of discontinuation among participants randomised to fixed-dose combination was higher (14% versus 11%, RR 1.26 95% CI 1.02 to 1.55). The weighted mean differences in systolic and diastolic blood pressure between the intervention and control arms were -7.05 mmHg (95% CI -10.18 to -3.87) and -3.65 mmHg (95% CI -5.44 to -1.85), respectively. The weighted mean differences (95% CI) in total and LDL cholesterol between the intervention and control arms were -0.75 mmol/L (95% CI -1.05 to -0.46) and -0.81 mmol/L (95% CI -1.09 to -0.53), respectively. There was a high degree of statistical heterogeneity in comparisons of blood pressure and lipids (I(2) ≥ 70% for all) that could not be explained, so these results should be viewed with caution. Fixed-dose combination therapy improved adherence to a multi-drug strategy by 33% (26% to 41%) compared with usual care, but this comparison was reported in only one study. The effects of fixed-dose combination therapy on quality of life are uncertain, though these results were reported in only one trial. No trials reported costs. AUTHORS' CONCLUSIONS: Compared with placebo, single drug active component, or usual care, the effects of fixed-dose combination therapy on all-cause mortality or CVD events are uncertain; only few trials report these outcomes and the included trials were primarily designed to observe changes in CVD risk factor levels rather than clinical events. Reductions in blood pressure and lipid parameters are generally lower than those previously projected, though substantial heterogeneity of results exists. Fixed-dose combination therapy is associated with modest increases in adverse events compared with placebo, single drug active component, or usual care but may be associated with improved adherence to a multidrug regimen. Ongoing trials of fixed-dose combination therapy will likely inform key outcomes.


Assuntos
Anticolesterolemiantes/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Aspirina/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Inibidores da Agregação Plaquetária/administração & dosagem , Doenças Cardiovasculares/mortalidade , Combinação de Medicamentos , Humanos , Efeito Placebo , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Ecology ; 105(7): e4326, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38845219

RESUMO

Integrated community models-an emerging framework in which multiple data sources for multiple species are analyzed simultaneously-offer opportunities to expand inferences beyond the single-species and single-data-source approaches common in ecology. We developed a novel integrated community model that combines distance sampling and single-visit count data; within the model, information is shared among data sources (via a joint likelihood) and species (via a random-effects structure) to estimate abundance patterns across a community. Parameters relating to abundance are shared between data sources, and the model can specify either shared or separate observation processes for each data source. Simulations demonstrated that the model provided unbiased estimates of abundance and detection parameters even when detection probabilities varied between the data types. The integrated community model also provided more accurate and more precise parameter estimates than alternative single-species and single-data-source models in many instances. We applied the model to a community of 11 herbivore species in the Masai Mara National Reserve, Kenya, and found considerable interspecific variation in response to local wildlife management practices: Five species showed higher abundances in a region with passive conservation enforcement (median across species: 4.5× higher), three species showed higher abundances in a region with active conservation enforcement (median: 3.9× higher), and the remaining three species showed no abundance differences between the two regions. Furthermore, the community average of abundance was slightly higher in the region with active conservation enforcement but not definitively so (posterior mean: higher by 0.20 animals; 95% credible interval: 1.43 fewer animals, 1.86 more animals). Our integrated community modeling framework has the potential to expand the scope of inference over space, time, and levels of biological organization, but practitioners should carefully evaluate whether model assumptions are met in their systems and whether data integration is valuable for their applications.


Assuntos
Modelos Biológicos , Animais , Quênia , Ecossistema , Especificidade da Espécie , Conservação dos Recursos Naturais/métodos , Densidade Demográfica
9.
SAGE Open Med Case Rep ; 11: 2050313X221145618, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113388

RESUMO

Papillary muscle rupture is a life-threatening complication of acute myocardial infarction that most commonly occurs 2-7 days after the infarct. We present a rare case of acute partial anterolateral papillary muscle rupture following non-ST elevation myocardial infarction. Our patient was an elderly male who had a detached anterolateral papillary muscle, which required emergent mitral valve replacement. Papillary muscle rupture is a rare complication of acute myocardial infarction, and anterolateral muscle rupture occurs even less commonly. When papillary muscle rupture is diagnosed, patients need to be emergently referred to cardiothoracic surgery as mortality without surgery is over 90% within a week.

10.
Artigo em Inglês | MEDLINE | ID: mdl-25267903

RESUMO

This is the protocol for a review and there is no abstract. The objectives are as follows: To determine the effectiveness of fixed-dose combination therapy on optimising CVD risk factors and reducing CVD fatal and non-fatal events for both primary and secondary prevention of CVD. Details of CVD events and risk factors included are listed in the methods. We will also determine any adverse events associated with taking fixed-dose combination therapy. This will include studies conducted in both developed and developing regions of the world.

11.
Ecology ; 102(1): e03204, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32970847

RESUMO

Integrated models combine multiple data types within a unified analysis to estimate species abundance and covariate effects. By sharing biological parameters, integrated models improve the accuracy and precision of estimates compared to separate analyses of individual data sets. We developed an integrated point process model to combine presence-only and distance sampling data for estimation of spatially explicit abundance patterns. Simulations across a range of parameter values demonstrate that our model can recover estimates of biological covariates, but parameter accuracy and precision varied with the quantity of each data type. We applied our model to a case study of black-backed jackals in the Masai Mara National Reserve, Kenya, to examine effects of spatially varying covariates on jackal abundance patterns. The model revealed that jackals were positively affected by anthropogenic disturbance on the landscape, with highest abundance estimated along the Reserve border near human activity. We found minimal effects of landscape cover, lion density, and distance to water source, suggesting that human use of the Reserve may be the biggest driver of jackal abundance patterns. Our integrated model expands the scope of ecological inference by taking advantage of widely available presence-only data, while simultaneously leveraging richer, but typically limited, distance sampling data.


Assuntos
Leões , Animais , Humanos , Quênia , Densidade Demográfica
12.
Nat Ecol Evol ; 5(10): 1441-1452, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34282317

RESUMO

Declines in the abundance and diversity of insects pose a substantial threat to terrestrial ecosystems worldwide. Yet, identifying the causes of these declines has proved difficult, even for well-studied species like monarch butterflies, whose eastern North American population has decreased markedly over the last three decades. Three hypotheses have been proposed to explain the changes observed in the eastern monarch population: loss of milkweed host plants from increased herbicide use, mortality during autumn migration and/or early-winter resettlement and changes in breeding-season climate. Here, we use a hierarchical modelling approach, combining data from >18,000 systematic surveys to evaluate support for each of these hypotheses over a 25-yr period. Between 2004 and 2018, breeding-season weather was nearly seven times more important than other factors in explaining variation in summer population size, which was positively associated with the size of the subsequent overwintering population. Although data limitations prevent definitive evaluation of the factors governing population size between 1994 and 2003 (the period of the steepest monarch decline coinciding with a widespread increase in herbicide use), breeding-season weather was similarly identified as an important driver of monarch population size. If observed changes in spring and summer climate continue, portions of the current breeding range may become inhospitable for monarchs. Our results highlight the increasingly important contribution of a changing climate to insect declines.


Assuntos
Asclepias , Borboletas , Migração Animal , Animais , Ecossistema , Dinâmica Populacional
13.
PLoS One ; 16(5): e0251395, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33989313

RESUMO

OBJECTIVE: Evidence for the management of acute otitis externa (AOE) is limited, with unclear diagnostic criteria and variably reported outcome measures that may not reflect key stakeholder priorities. We aimed to develop 1) a definition, 2) diagnostic criteria and 3) a core outcome set (COS) for AOE. STUDY DESIGN: COS development according to Core Outcome Measures in Effectiveness Trials (COMET) methodology and parallel consensus selection of diagnostic criteria/definition. SETTING: Stakeholders from the United Kingdom. SUBJECTS AND METHODS: Comprehensive literature review identified candidate items for the COS, definition and diagnostic criteria. Nine individuals with past AOE generated further patient-centred candidate items. Candidate items were rated for importance by patient and professional (ENT doctors, general practitioners, microbiologists, nurses, audiologists) stakeholders in a three-round online Delphi exercise. Consensus items were grouped to form the COS, diagnostic criteria, and definition. RESULTS: Candidate COS items from patients (n = 28) and literature (n = 25) were deduplicated and amalgamated to a final candidate list (n = 46). Patients emphasised quality-of-life and the impact on daily activities/work. Via the Delphi process, stakeholders agreed on 31 candidate items. The final COS covered six outcomes: pain; disease severity; impact on quality-of-life and daily activities; patient satisfaction; treatment-related outcome; and microbiology. 14 candidate diagnostic criteria were identified, 8 reaching inclusion consensus. The final definition for AOE was 'diffuse inflammation of the ear canal skin of less than 6 weeks duration'. CONCLUSION: The development and adoption of a consensus definition, diagnostic criteria and a COS will help to standardise future research in AOE, facilitating meta-analysis. Consulting former patients throughout development highlighted deficiencies in the outcomes adopted previously, in particular concerning the impact of AOE on daily life.


Assuntos
Orelha Externa/patologia , Otite Externa/diagnóstico , Otite Externa/patologia , Dor/diagnóstico , Atividades Cotidianas , Técnica Delphi , Humanos , Otite Externa/terapia , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Resultado do Tratamento
14.
Head Neck Pathol ; 13(3): 507-511, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29744825

RESUMO

The autosomal dominant Birt-Hogg-Dubé syndrome is known to be associated with skin, lung and kidney lesions. It is caused by heterozygous germline mutations in the folliculin gene and has a high penetrance. We report the case of a 51 year old woman with Birt-Hogg-Dubé syndrome who presented with a laryngeal mass. Imaging confirmed a mass centered on the piriform sinus and following excision histological examination confirmed the lesion was composed of polygonal cells with abundant eosinophilic cytoplasm consistent with a rhabdomyoma. Laryngeal rhabdomyoma is rare condition and has not been previously described in association with Birt-Hogg-Dubé. In patients with Birt-Hogg-Dubé syndrome who develop upper aerodigestive tract symptoms secondary to mass lesion an adult-type rhabdomyoma might be considered as a differential, with endoscopic excision being the treatment of choice.


Assuntos
Síndrome de Birt-Hogg-Dubé/complicações , Neoplasias Laríngeas/patologia , Rabdomioma/patologia , Feminino , Humanos , Neoplasias Laríngeas/genética , Pessoa de Meia-Idade , Rabdomioma/genética
15.
Burns ; 45(6): 1379-1385, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31079961

RESUMO

INTRODUCTION: Patients with burn injuries are at an increased risk of venous thromboembolism (VTE). This predisposition is secondary to the endothelial injury, hyper-coagulable state and stasis (Virchow's triad) associated with burn injury. Although the true incidence of VTE in burn patients has not been adequately quantified, symptomatic VTE occurs in 0.2-7% of this population. VTE prophylaxis has proven clinical effectiveness and affords a reduction in the morbidity associated with such events, but the benefits and risk of complications need to be balanced in order to provide the best quality of care. Owing to the lack of prospective data on VTE in burns, practice varies greatly, not only internationally, but also between local burns services. Our aim was to better understand current VTE practice within United Kingdom (UK) burn care services by performing a comprehensive survey. METHODS: We contacted all the inpatient burn care services in the UK and collected data on current VTE practice via a standardised questionnaire. Services were given the choice to complete the survey by telephone or email and a follow-up plan was formulated. RESULTS: Twenty-five burn care services were contacted and 23 agreed to participate (92% response rate). Responding services treated adults, children or both and lead burn nurses or senior medical staff familiar with current VTE practice were interviewed. Routine VTE prophylaxis was provided in 84% of burn services and the majority utilised a combination of chemoprophylaxis and thromboembolic deterrent stockings (TEDS). All used low molecular weight heparin (LMWH) as their choice of chemoprophylaxis. Of those treating adults, all used a VTE prophylaxis protocol, but none of these applied to children. Only 56% of services treating children had such a protocol. The majority discontinued prophylaxis once patients were mobile. DISCUSSION AND CONCLUSION: Although the true burden of VTE in burn patients is unknown, we recognise that they are a population at risk. In addition to changes in the inflammatory and clotting pathways associated with thermal injury, prolonged hospital stay, ventilatory support, multiple surgeries, numerous central venous cannulations and reduced mobility all multiply this risk. The risk associated with the administration of heparin (bleeding complications and heparin-induced thrombocytopaenia) is low and can be reduced even further to 0.1% by the use of LMWH. The risk of symptomatic VTE is far greater, therefore the benefits of VTE prophylaxis would seem to outweigh the risks of not undertaking prophylactic measures. A higher LMWH dose and routine monitoring of anti-factor Xa levels are useful for acute burn patients. Two previous surveys, performed in Canada and the United States of America (USA), found routine administration of VTE prophylaxis to be 50% and 76% respectively. Of the 71 centres in the USA participating in the survey, 30% used a combination of sequential compression devices (SCD) and heparin and 24% did not provide VTE prophylaxis at all. A lack of prospective data on VTE in burn patients appears to be associated with diverse practice, and consensus on this topic could ensure that the potential morbidity caused by VTE is reduced. A clinical tool for identifying patients at risk and guidelines for management will standardise practice, which in turn should allow us to improve and maintain high quality care for burn patients.


Assuntos
Anticoagulantes/uso terapêutico , Queimaduras/terapia , Heparina de Baixo Peso Molecular/uso terapêutico , Padrões de Prática Médica , Meias de Compressão , Tromboembolia Venosa/prevenção & controle , Adulto , Queimaduras/complicações , Criança , Gerenciamento Clínico , Humanos , Medição de Risco , Reino Unido , Tromboembolia Venosa/complicações
16.
Philos Trans R Soc Lond B Biol Sci ; 374(1781): 20180052, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31352879

RESUMO

Mammalian carnivores are declining worldwide owing to human activities. Behavioural indicators have the potential to help identify population trends and inform conservation actions, although this area of research is understudied. We investigate whether behaviour is linked to abundance in a community of carnivores in the Masai Mara National Reserve, Kenya. Anthropogenic disturbance increased exponentially in parts of the Reserve between 1988 and 2017, mainly owing to daily incursions by large numbers of livestock and tourists. Previous research showed that hyena behaviour changed markedly during this period. Through a series of vignettes, we inquire whether hyena behaviours correlate with changes in abundance of hyenas themselves, or those of other carnivore species in the region. We find that changes in spotted hyena behaviour in disturbed areas, but not in undisturbed areas, can be linked to changes in their demography (vignette 1). We also find that declines in observed lion-hyena interactions, as well as increases in spotted hyena abundance, are probably caused by competitive release of hyenas from declining lion abundance (vignette 2). Finally, we demonstrate that in some cases, hyena behaviour and demography is linked to the density and distribution of sympatric carnivores, and that behavioural changes in hyenas can provide information on shifts within the carnivore community (vignettes 3 and 4). Our vignettes reveal intriguing relationships between behaviour and demography that should be explored in future research. Pairing behavioural studies with more traditional monitoring efforts can yield useful insights regarding population and community trends, and aid wildlife conservation and management. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.


Assuntos
Conservação dos Recursos Naturais , Hyaenidae , Leões , Simpatria , Animais , Carnívoros , Quênia , Dinâmica Populacional
17.
Ecology ; 100(6): e02714, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30927256

RESUMO

A common challenge for studying wildlife populations occurs when different survey methods provide inconsistent or incomplete inference on the trend, dynamics, or viability of a population. A potential solution to the challenge of conflicting or piecemeal data relies on the integration of multiple data types into a unified modeling framework, such as integrated population models (IPMs). IPMs are a powerful approach for species that inhabit spatially and seasonally complex environments. We provide guidance on exploiting the capabilities of IPMs to address inferential discrepancies that stem from spatiotemporal data mismatches. We illustrate this issue with analysis of a migratory species, the American Woodcock (Scolopax minor), in which individual monitoring programs suggest differing population trends. To address this discrepancy, we synthesized several long-term data sets (1963-2015) within an IPM to estimate continental-scale population trends, and link dynamic drivers across the full annual cycle and complete extent of the woodcock's geographic range in eastern North America. Our analysis reveals the limiting portions of the life cycle by identifying time periods and regions where vital rates are lowest and most variable, as well as which demographic parameters constitute the main drivers of population change. We conclude by providing recommendations for resolving conflicting population estimates within an integrated modeling approach, and discuss how strategies (e.g., data thinning, expert opinion elicitation) from other disciplines could be incorporated into ecological analyses when attempting to combine multiple, incongruent data types.


Assuntos
Charadriiformes , Ecologia , Animais , Animais Selvagens , Demografia , Dinâmica Populacional
18.
J Eval Clin Pract ; 22(1): 93-97, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26314274

RESUMO

RATIONALE, AIMS AND OBJECTIVES: The pressure to deliver quality care with finite resources means that dealing with single-symptom conditions like tinnitus in an efficient and individualized manner has never been more important. Both primary and secondary care practitioners have an obligation to explore efficient delivery of simple management pathways. Commissioners of health care are in a unique position to affect evidence-based strategic change in the management of uncomplicated tinnitus. This study is an attempt to explore one such option. We present the outcomes of a tinnitus patient pathway designed for one-stop management, thereby minimizing unnecessary additional appointments. METHOD: A retrospective observational cohort study of 452 patients referred to a NHS one-stop tinnitus clinic from 2008 to 2012. Clinical care guided was through the use of a structured approach to history taking, neurotological examination and management. RESULTS: 294 out of 452 (65%) of patients referred had unilateral tinnitus. The most common associated complaints were hearing loss (387/452, 86%) and hyperacusis (329/452, 73%). 210 (46%) of patients had their presenting complaint dealt with in a single clinic visit. CONCLUSION: A structured system for referral and management of tinnitus within the health system ensures patients have timely access to evidence-based investigation and treatment. A consistent approach to imaging aimed at identifying retrocochlear pathology can benefit patients through early diagnosis of central pathology and the reassurance provided by a negative scan.


Assuntos
Comportamento Cooperativo , Avaliação de Resultados em Cuidados de Saúde , Administração dos Cuidados ao Paciente , Zumbido/terapia , Instituições de Assistência Ambulatorial , Acessibilidade aos Serviços de Saúde , Humanos , Estudos Retrospectivos
19.
Otol Neurotol ; 34(1): 180-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23032665

RESUMO

OBJECTIVE: To present the rise and decline of allograft tympanoplasty and investigate how the challenges it has faced may inform us of its future. DATA SOURCES: Articles and books published over the last 48 years that refer to allograft tympanoplasty or its historical roots. HISTORY: The first published account of allograft tympanoplasty is by Ned Chalat in 1964; however, whether he was the first to use the technique is controversial. In 1966, Jean Marquet published the first clinically successful use of allograft tympanic membranes. Since that time, a number of surgeons have trialed both en bloc tympano-ossicular techniques and tympanomeatal techniques with separate ossicle interposition or columellar reconstruction, often with considerable success. The advent of the human immunodeficiency virus and Creutzfeldt-Jakob's disease resulted in a reduction in its application; however, a number of centers are still successfully using the technique in their current practice. CONCLUSION: Whether allograft tympanoplasty will have a place in the future of otology remains to be seen, but an understanding of the history of this technique is essential in evaluating its merit.


Assuntos
Timpanoplastia/história , História do Século XX , Humanos , Transplante Homólogo/história , Transplante Homólogo/métodos , Membrana Timpânica/cirurgia , Timpanoplastia/métodos
20.
Otol Neurotol ; 33(2): 270-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22222571

RESUMO

OBJECTIVE: To present the fascinating, controversial, and tumultuous history of tympanic cautery as a form of myringoplasty and describe the relevance of work more than 150 years old to modern practice and research. DATA SOURCES: More than 70 English, French, and German articles and books published over the last 400 years, which refer to some aspect of tympanic membrane cautery. HISTORY: The first recorded use of silver nitrate to stimulate closure of tympanic membrane perforations is by William Wilde in 1848. Since then, numerous modifications of this technique have been used, and its significance has waxed and waned in response to events within the speciality of otology and the wider world. CONCLUSION: There are lessons to be learned from the rise and fall of this once widely practiced technique. There exists a school of thought that believes that the significance of cautery lies not only in the history of otology but also in its future.


Assuntos
Cauterização/história , Cauterização/métodos , Miringoplastia/história , Miringoplastia/métodos , Otolaringologia/história , Membrana Timpânica/cirurgia , Cáusticos , História do Século XIX , História do Século XX , Humanos , Irlanda , Nitrato de Prata , Transplante de Pele/história
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