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1.
Ecol Evol ; 11(9): 4205-4217, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33976804

RESUMO

Dry deciduous dipterocarp forests (DDF) cover about 15%-20% of Southeast Asia and are the most threatened forest type in the region. The jungle cat (Felis chaus) is a DDF specialist that occurs only in small isolated populations in Southeast Asia. Despite being one of the rarest felids in the region, almost nothing is known about its ecology. We investigated the ecology of jungle cats and their resource partitioning with the more common leopard cats (Prionailurus bengalensis) in a DDF-dominated landscape in Srepok Wildlife Sanctuary, Cambodia. We used camera-trap data collected from 2009 to 2019 and DNA-confirmed scats to determine the temporal, dietary and spatial overlap between jungle cats and leopard cats. The diet of jungle cats was relatively diverse and consisted of murids (56% biomass consumed), sciurids (15%), hares (Lepus peguensis; 12%), birds (8%), and reptiles (8%), whereas leopard cats had a narrower niche breadth and a diet dominated by smaller prey, primarily murids (73%). Nonetheless, dietary overlap was high because both felid species consumed predominantly small rodents. Both species were primarily nocturnal and had high temporal overlap. Two-species occupancy modelling suggested jungle cats were restricted to DDF and had low occupancy, whereas leopard cats had higher occupancy and were habitat generalists. Our study confirmed that jungle cats are DDF specialists that likely persist in low numbers due to the harsh conditions of the dry season in this habitat, including annual fires and substantial decreases in small vertebrate prey. The lower occupancy and more diverse diet of jungle cats, together with the broader habitat use of leopard cats, likely facilitated the coexistence of these species. The low occupancy of jungle cats in DDF suggests that protection of large areas of DDF will be required for the long-term conservation of this rare felid in Southeast Asia.

3.
Br J Dermatol ; 182(5): 1148-1157, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31520533

RESUMO

BACKGROUND: Guidelines for follow-up of patients with melanoma are based on limited evidence. OBJECTIVES: To guide skin surveillance, we developed a risk prediction model for subsequent primary melanomas, using demographic, phenotypical, histopathological, sun exposure and genomic risk factors. METHODS: Using Cox regression frailty models, we analysed data for 2613 primary melanomas from 1266 patients recruited to the population-based Genes, Environment and Melanoma study in New South Wales, Australia, with a median of 14 years' follow-up via the cancer registry. Discrimination and calibration were assessed. RESULTS: The median time to diagnosis of a subsequent primary melanoma decreased with each new primary melanoma. The final model included 12 risk factors. Harrell's C-statistic was 0·73 [95% confidence interval (CI) 0·68-0·77], 0·65 (95% CI 0·62-0·68) and 0·65 (95% CI 0·61-0·69) for predicting second, third and fourth primary melanomas, respectively. The risk of a subsequent primary melanoma was 4·75 times higher (95% CI 3·87-5·82) for the highest vs. the lowest quintile of the risk score. The mean absolute risk of a subsequent primary melanoma within 5 years was 8·0 ± SD 4.1% after the first primary melanoma, and 46·8 ± 15·0% after the second, but varied substantially by risk score. CONCLUSIONS: The risk of developing a subsequent primary melanoma varies considerably between individuals and is particularly high for those with two or more primary melanomas. The risk prediction model and its associated nomograms enable estimation of the absolute risk of subsequent primary melanoma, on the basis of on an individual's risk factors, and can be used to tailor surveillance intensity, communicate risk and provide patient education. What's already known about this topic? Current guidelines for the frequency and length of follow-up to detect new primary melanomas in patients with one or more previous primary melanomas are based on limited evidence. People with one or more primary melanomas have, on average, a higher risk of developing another primary invasive melanoma, compared with the general population, but an accurate way of estimating individual risk is needed. What does this study add? We provide a comprehensive risk prediction model for subsequent primary melanomas, using data from 1266 participants with melanoma (2613 primary melanomas), over a median 14 years' follow-up. The model includes 12 risk factors comprising demographic, phenotypical, histopathological and genomic factors, and sun exposure. It enables estimation of the absolute risk of subsequent primary melanomas, and can be used to tailor surveillance intensity, communicate individual risk and provide patient education.


Assuntos
Melanoma , Neoplasias Cutâneas , Austrália , Estudos de Coortes , Humanos , Melanoma/epidemiologia , Melanoma/etiologia , New South Wales/epidemiologia , Fatores de Risco , Neoplasias Cutâneas/epidemiologia
4.
Commun Biol ; 2: 396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31701025

RESUMO

Habitat degradation and hunting have caused the widespread loss of larger vertebrate species (defaunation) from tropical biodiversity hotspots. However, these defaunation drivers impact vertebrate biodiversity in different ways and, therefore, require different conservation interventions. We conducted landscape-scale camera-trap surveys across six study sites in Southeast Asia to assess how moderate degradation and intensive, indiscriminate hunting differentially impact tropical terrestrial mammals and birds. We found that functional extinction rates were higher in hunted compared to degraded sites. Species found in both sites had lower occupancies in the hunted sites. Canopy closure was the main predictor of occurrence in the degraded sites, while village density primarily influenced occurrence in the hunted sites. Our findings suggest that intensive, indiscriminate hunting may be a more immediate threat than moderate habitat degradation for tropical faunal communities, and that conservation stakeholders should focus as much on overhunting as on habitat conservation to address the defaunation crisis.


Assuntos
Biodiversidade , Clima Tropical , Animais , Sudeste Asiático , Teorema de Bayes , Aves , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Ecossistema , Extinção Biológica , Mamíferos , Dinâmica Populacional/estatística & dados numéricos , Dinâmica Populacional/tendências , Especificidade da Espécie
5.
Conserv Biol ; 33(3): 697-708, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30615823

RESUMO

We developed a method to estimate population abundance from simultaneous counts of unmarked individuals over multiple sites. We considered that at each sampling occasion, individuals in a population could be detected at 1 of the survey sites or remain undetected and used either multinomial or binomial simultaneous-count models to estimate abundance, the latter being equivalent to an N-mixture model with one site. We tested model performance with simulations over a range of detection probabilities, population sizes, growth rates, number of years, sampling occasions, and sites. We then applied our method to 3 critically endangered vulture species in Cambodia to demonstrate the real-world applicability of the model and to provide the first abundance estimates for these species in Cambodia. Our new approach works best when existing methods are expected to perform poorly (i.e., few sites and large variation in abundance among sites) and if individuals may move among sites between sampling occasions. The approach performed better when there were >8 sampling occasions and net probability of detection was high (>0.5). We believe our approach will be useful in particular for simultaneous surveys at aggregation sites, such as roosts. The method complements existing approaches for estimating abundance of unmarked individuals and is the first method designed specifically for simultaneous counts.


Modelos de Conteo Simultáneo para Estimar la Abundancia a partir de Conteos de Individuos No Marcados con Detección Imperfecta Resumen Desarrollamos un método para estimar la abundancia poblacional a partir de conteos simultáneos de individuos sin marcaje en múltiples sitios. Consideramos que en cada ocasión de muestreo los individuos de una población podrían ser detectados en uno de los sitios de censos o podrían permanecer sin ser detectados y usamos modelos de conteo simultáneo multinomial o binomial para estimar la abundancia, con el binomial como equivalente a un modelo de mezcla N con un solo sitio. Probamos el desempeño del modelo con simulaciones en un rango de probabilidades de detección, tamaños poblacionales, tasas de crecimiento, número de años, ocasiones de muestreo, y sitios. Después aplicamos nuestro método a tres especies de buitre que se encuentran en peligro crítico en Camboya para demostrar cuán aplicable es el modelo en el mundo real y para proporcionar las primeras estimaciones de abundancia para estas especies en Camboya. Nuestra nueva estrategia trabaja de mejor manera cuando se espera que los modelos existentes tengan un desempeño pobre (es decir, pocos sitios y una gran variación en la abundancia entre sitios) y si los individuos podrían moverse de un sitio a otro entre cada ocasión de muestreo. La estrategia tuvo un mejor desempeñó cuando hubo >8 ocasiones de muestreo y la probabilidad neta de detección fue alta (>0.5). Creemos que nuestra estrategia será especialmente útil para censos simultáneos en sitios de agregación, como los nidos. El método complementa las estrategias existentes para estimar la abundancia de individuos sin marcaje y es el primer método diseñado específicamente para conteos simultáneos.


Assuntos
Aves , Conservação dos Recursos Naturais , Animais , Camboja , Modelos Estatísticos , Densidade Demográfica , Probabilidade
6.
PLoS One ; 13(11): e0207114, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30408090

RESUMO

With less than 3200 wild tigers in 2010, the heads of 13 tiger-range countries committed to doubling the global population of wild tigers by 2022. This goal represents the highest level of ambition and commitment required to turn the tide for tigers in the wild. Yet, ensuring efficient and targeted implementation of conservation actions alongside systematic monitoring of progress towards this goal requires that we set site-specific recovery targets and timelines that are ecologically realistic. In this study, we assess the recovery potential of 18 sites identified under WWF's Tigers Alive Initiative. We delineated recovery systems comprising a source, recovery site, and support region, which need to be managed synergistically to meet these targets. By using the best available data on tiger and prey numbers, and adapting existing species recovery frameworks, we show that these sites, which currently support 165 (118-277) tigers, have the potential to harbour 585 (454-739) individuals. This would constitute a 15% increase in the global population and represent over a three-fold increase within these specific sites, on an average. However, it may not be realistic to achieve this target by 2022, since tiger recovery in 15 of these 18 sites is contingent on the initial recovery of prey populations, which is a slow process. We conclude that while sustained conservation efforts can yield significant recoveries, it is critical that we commit our resources to achieving the biologically realistic targets for these sites even if the timelines are extended.


Assuntos
Espécies em Perigo de Extinção , Tigres , Animais , Ásia , Objetivos , Densidade Demográfica , Comportamento Predatório , Fatores de Tempo
7.
Mol Ecol Resour ; 18(6): 1282-1298, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29877042

RESUMO

The use of environmental DNA (eDNA) has become an applicable noninvasive tool with which to obtain information about biodiversity. A subdiscipline of eDNA is iDNA (invertebrate-derived DNA), where genetic material ingested by invertebrates is used to characterize the biodiversity of the species that served as hosts. While promising, these techniques are still in their infancy, as they have only been explored on limited numbers of samples from only a single or a few different locations. In this study, we investigate the suitability of iDNA extracted from more than 3,000 haematophagous terrestrial leeches as a tool for detecting a wide range of terrestrial vertebrates across five different geographical regions on three different continents. These regions cover almost the full geographical range of haematophagous terrestrial leeches, thus representing all parts of the world where this method might apply. We identify host taxa through metabarcoding coupled with high-throughput sequencing on Illumina and IonTorrent sequencing platforms to decrease economic costs and workload and thereby make the approach attractive for practitioners in conservation management. We identified hosts in four different taxonomic vertebrate classes: mammals, birds, reptiles and amphibians, belonging to at least 42 different taxonomic families. We find that vertebrate blood ingested by haematophagous terrestrial leeches throughout their distribution is a viable source of DNA with which to examine a wide range of vertebrates. Thus, this study provides encouraging support for the potential of haematophagous terrestrial leeches as a tool for detecting and monitoring terrestrial vertebrate biodiversity.


Assuntos
Análise Química do Sangue/métodos , Código de Barras de DNA Taxonômico/métodos , Monitoramento Ambiental/métodos , Sanguessugas/crescimento & desenvolvimento , Metagenômica/métodos , Anfíbios/parasitologia , Animais , Aves/parasitologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mamíferos/parasitologia , Répteis/parasitologia
8.
Br J Dermatol ; 179(3): 590-598, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29570779

RESUMO

BACKGROUND: The management of histologically dysplastic naevi (HDN) with re-excision vs. observation remains controversial because of lack of evidence about associated melanoma outcomes. OBJECTIVES: To assess published data on the development of biopsy-site primary cutaneous melanoma among biopsy-proven HDN managed with either re-excision or observation. METHODS: A systematic review of all published data: a total of 5293 records were screened, 18 articles were assessed in full text and 12 studies met inclusion criteria. No controlled trials were identified. RESULTS: Most studies (11 of 12, 92%) were retrospective chart reviews, and one was both a cross-sectional and cohort study. Many studies (nine of 12, 75%) had no head-to-head comparison groups and either only reported HDN that were re-excised or observed. A total of 2673 (1535 observed vs. 1138 re-excised) HDN of various grades were included. Follow-up varied between 2 weeks and 30 years. Nine studies reported that no melanomas developed. Eleven biopsy-site melanomas developed across three of the studies, six among observed lesions (0·39%) and five among re-excised lesions (0·44%). CONCLUSIONS: Based upon the available evidence the rates of biopsy-site primary melanoma were similarly low among observed lesions and re-excised lesions. This suggests that HDNs can be observed with minimal adverse melanoma-associated outcomes. However, all included articles were of low quality and further prospective trials could better guide clinical decision making.


Assuntos
Procedimentos Cirúrgicos Dermatológicos/métodos , Síndrome do Nevo Displásico/terapia , Melanoma/prevenção & controle , Neoplasias Cutâneas/terapia , Conduta Expectante , Biópsia , Tomada de Decisão Clínica , Síndrome do Nevo Displásico/diagnóstico , Síndrome do Nevo Displásico/patologia , Humanos , Melanoma/diagnóstico , Melanoma/patologia , Retratamento/métodos , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
10.
PLoS One ; 12(8): e0183247, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28820901

RESUMO

Pressures on freshwater biodiversity in Southeast Asia are accelerating yet the status and conservation needs of many of the region's threatened fish species are unclear. This impacts the ability to implement conservation activities and to understand the effects of infrastructure developments and other hydrological changes. We used Local Ecological Knowledge from fishing communities on the Mekong River in the Siphandone waterscape, Lao PDR to estimate mean and mode last capture dates of eight rare or culturally significant fish species in order to provide conservation monitoring baselines. One hundred and twenty fishermen, from six villages, were interviewed. All eight species had been captured, by at least one of the interviewees, within the waterscape within the past year. However the mean and mode last capture dates varied between the species. Larger species, and those with higher Red List threat status, were caught less recently than smaller species of less conservation concern. The status of the Critically Endangered Pangasius sanitwongsei (mean last capture date 116.4 months) is particularly worrying suggesting severe population decline although cultural issues may have caused this species to have been under-reported. This highlights that studies making use of Local Ecological Knowledge need to understand the cultural background and context from which data is collected. Nevertheless we recommend our approach, of stratified random interviews to establish mean last capture dates, may be an effective methodology for monitoring freshwater fish species of conservation concern within artisanal fisheries. If fishing effort remains relatively constant, or if changes in fishing effort are accounted for, differences over time in mean last capture dates are likely to represent changes in the status of species. We plan to repeat our interview surveys within the waterscape as part of a long-term fish-monitoring program.


Assuntos
Ecologia , Monitoramento Ambiental/métodos , Animais , Biodiversidade , Feminino , Peixes , Humanos , Laos , Masculino
14.
Nature ; 512(7513): 171-3, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-25079321

RESUMO

The solar neighbourhood is the closest and most easily studied sample of the Galactic interstellar medium, an understanding of which is essential for models of star formation and galaxy evolution. Observations of an unexpectedly intense diffuse flux of easily absorbed 1/4-kiloelectronvolt X-rays, coupled with the discovery that interstellar space within about a hundred parsecs of the Sun is almost completely devoid of cool absorbing gas, led to a picture of a 'local cavity' filled with X-ray-emitting hot gas, dubbed the local hot bubble. This model was recently challenged by suggestions that the emission could instead be readily produced within the Solar System by heavy solar-wind ions exchanging electrons with neutral H and He in interplanetary space, potentially removing the major piece of evidence for the local existence of million-degree gas within the Galactic disk. Here we report observations showing that the total solar-wind charge-exchange contribution is approximately 40 per cent of the 1/4-keV flux in the Galactic plane. The fact that the measured flux is not dominated by charge exchange supports the notion of a million-degree hot bubble extending about a hundred parsecs from the Sun.

16.
Hum Immunol ; 73(6): 673-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22521571

RESUMO

T-bet is a transcription factor that drives the Th1 immune response primarily through promoting expression of the IFN-γ gene. Polymorphisms in the T-bet gene, TBX21, have been associated with immune-mediated diseases such as asthma and systemic sclerosis. We found that the TBX21 promoter polymorphism T-1993C is associated with a significant decrease in IL-4 and IFN-γ production by stimulated primary human lymphocytes from healthy participants.


Assuntos
Interferon gama/biossíntese , Interleucina-4/biossíntese , Linfócitos/imunologia , Polimorfismo de Nucleotídeo Único , Proteínas com Domínio T/genética , Adolescente , Adulto , Idoso , Feminino , Regulação da Expressão Gênica/imunologia , Estudos de Associação Genética , Humanos , Interferon gama/imunologia , Interleucina-4/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Regiões Promotoras Genéticas/imunologia , Proteínas com Domínio T/imunologia , Acetato de Tetradecanoilforbol/farmacologia
18.
Scand J Med Sci Sports ; 21(6): e341-50, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21518010

RESUMO

The purpose of this study was to examine the effects of exercising at different intensities over 7 weeks on components of physical fitness and CVD risk factors. Forty-seven boys and 10 girls, (16.4±0.7 years of age) were divided into a moderate, high intensity, or a control group. All participants had indices of obesity and blood pressure recorded in addition to four physical performance measures pre- and post-intervention. In addition, the intervention groups repeated the physical performance measures at the 4th week phase of the intervention. Following the intervention, significant improvements (P<0.05) in the high-intensity group were found in the 20 MSFT, agility, CMJ and 10 m sprint post-intervention. Participants in the moderate intensity group displayed significant improvements (P<0.05) in both the CMJ and 20 MSFT post-intervention. Body fat % significantly improved (P<0.01) in the moderate group only post-intervention. Interestingly, Systolic blood pressure significantly improved post-intervention (112±10 vs 106±11 mmHg) (P=0.017) in the high intensity group. In conclusion, high-intensity exercise over 7 weeks is a very time efficient means of improving important components of physical fitness in adolescents.


Assuntos
Exercício Físico/fisiologia , Aptidão Física/fisiologia , Adolescente , Doenças Cardiovasculares/prevenção & controle , Estudos de Coortes , Feminino , Humanos , Masculino , Obesidade/prevenção & controle , Escócia , Inquéritos e Questionários
19.
Ann Hum Biol ; 38(1): 22-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20450386

RESUMO

BACKGROUND: This study examines CVD risk factors trends in Welsh adolescents between 2002 and 2007. PARTICIPANTS AND METHODS: CVD risk factor data was examined from two cross-sectional studies. The first study (73 participants; aged 12.9 ± 0.3 years) was completed in 2002. The second study (90 participants; aged 12.9 ± 0.4 years) was conducted in 2007. Measurements included body mass index (BMI), waist circumference (WC), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, fibrinogen (Fg) and high-sensitivity C-reactive protein (hs-CRP). RESULTS: In boys, mean BMI and WC were lower in 2007, although not significantly (p ≥ 0.05). In 2007, there were improvements in mean lipid, Fg and hs-CRP concentrations in both sexes (p < 0.05). In 2002, 42.8% of boys and 34.2% of girls were overweight or obese; in 2007, this was 23.7% and 28.9% for boys and girls, respectively. More adolescents in 2002 exceeded the recommended levels for lipids, Fg and hs-CRP. CONCLUSION: This is the only study to examine CVD risk factor trends in Welsh adolescents. Although overweight continues to be widespread in 12-13 year olds, this study did not identify significant mean changes in overweight and obesity between 2002 and 2007. Overall, the data presented a positive trend in lipid profile and inflammatory factors.


Assuntos
Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Inquéritos Epidemiológicos , Circunferência da Cintura , Adolescente , Pressão Sanguínea , Proteína C-Reativa/análise , Doenças Cardiovasculares/prevenção & controle , Criança , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Estudos Longitudinais , Masculino , Obesidade , Fatores de Risco , Triglicerídeos/sangue , País de Gales/epidemiologia
20.
J Sports Sci ; 28(12): 1361-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20853205

RESUMO

The aim of this study was to examine the effect of supra-maximal exercise on circulating concentrations of salivary testosterone, salivary cortisol, and salivary immunoglobulin A in female adolescents. Nineteen apparently healthy females aged 15-16 years participated in this study. All participants completed 668 s sprints, interspersed with 30 s recovery intervals on a cycle ergometer. Salivary testosterone, cortisol, and immunoglobulin A samples were taken before and 5 min after exercise. Experimental procedures continued over two mornings, at least 3 h after a light breakfast. Participants refrained from performing any strenuous physical activity for at least 24 h prior to the exercise test. None of the participants were engaged in a structured training programme. The group mean (± s) for peak power output was 562 ± 113.0 W. Female adolescents recruited for this study showed no changes in salivary testosterone, cortisol or immunoglobulin A following repeated bouts of supra-maximal cycling (P > 0.05). To date, there has been a paucity of information concerning adolescents' hormonal and mucosal immune function responses to supra-maximal exercise. Our data provide further guidance with regard to physical activities and sports prescription for female adolescents. Further research, on a larger sample of females, is required to elucidate the physiological significance of these findings.


Assuntos
Ciclismo/fisiologia , Exercício Físico/fisiologia , Hidrocortisona/análise , Imunoglobulina A Secretora/análise , Saliva/química , Testosterona/análise , Adolescente , Teste de Esforço , Feminino , Humanos , Imunidade nas Mucosas , Esforço Físico/fisiologia
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