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1.
Ecol Evol ; 13(7): e10353, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37502306

RESUMO

Habitat loss and fragmentation are leading contributors to the endangered status of species. In 2006, the Nakai Plateau contained the largest known Asian elephant (Elephas maximus) population in the Lao People's Democratic Republic (Lao PDR), and the population was among those with the highest genetic diversity reported for Asian elephants. In 2008, completion of the Nam Theun 2 hydroelectric dam inundated much of the Plateau, resulting in the loss of 40% of elephant habitat. We studied elephant presence, movements, and the incidence of human-elephant conflict (HEC) on the Nakai Plateau and surrounding areas from 2004 to 2020, before and for 12 years after dam completion. To examine contemporary population dynamics in the Nakai elephants, we used genetic sampling to compare minimum population numbers, demography, and levels of genetic diversity from the wet and dry seasons in 2018/2019, 10 years after dam completion, with those reported in a pre-dam-completion genetic survey. After dam completion, we found a major increase in HEC locally and the creation of new, serious, and persistent HEC problems as far as 100 km away. While we were unable to compare estimated population sizes before and after dam completion, our data revealed a decrease in genetic diversity, a male-biased sex ratio, and evidence of dispersal from the Plateau by breeding-age females. Our results raise concerns about the long-term viability of this important population as well as that of other species in this region. Given that hydropower projects are of economic importance throughout Laos and elsewhere in southeast Asia, this study has important implications for understanding and mitigating their impact.

2.
Conserv Biol ; 34(6): 1512-1524, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32390253

RESUMO

Approaches to assess the impacts of landscape disturbance scenarios on species range from metrics based on patterns of occurrence or habitat to comprehensive models that explicitly include ecological processes. The choice of metrics and models affects how impacts are interpreted and conservation decisions. We explored the impacts of 3 realistic disturbance scenarios on 4 species with different ecological and taxonomic traits. We used progressively more complex models and metrics to evaluate relative impact and rank of scenarios on the species. Models ranged from species distribution models that relied on implicit assumptions about environmental factors and species presence to highly parameterized spatially explicit population models that explicitly included ecological processes and stochasticity. Metrics performed consistently in ranking different scenarios in order of severity primarily when variation in impact was driven by habitat amount. However, they differed in rank for cases where dispersal dynamics were critical in influencing metapopulation persistence. Impacts of scenarios on species with low dispersal ability were better characterized using models that explicitly captured these processes. Metapopulation capacity provided rank orders that most consistently correlated with those from highly parameterized and data-rich models and incorporated information about dispersal with little additional computational and data cost. Our results highlight the importance of explicitly considering species' ecology, spatial configuration of habitat, and disturbance when choosing indicators of species persistence. We suggest using hybrid approaches that are a mixture of simple and complex models to improve multispecies assessments.


Medición de los Impactos sobre las Especies con Modelos y Medidas de Complejidad Ecológica y Computacional Variante Resumen Las estrategias para evaluar el impacto de los escenarios de perturbación de paisaje sobre la distribución de las especies van desde las medidas basadas en patrones de presencia o hábitat hasta los modelos integrales que incluyen explícitamente a los procesos ecológicos. La elección de medidas y modelos afecta la interpretación de los impactos y las decisiones de conservación. Exploramos los impactos de tres escenarios realistas de perturbación sobre cuatro especies con características ecológicas y taxonómicas diferentes. Usamos progresivamente modelos y medidas más complejas para evaluar el impacto relativo y la clasificación de los escenarios sobre las especies. Los modelos variaron desde aquellos de distribución de especies que dependen de las suposiciones implícitas acerca de los factores ambientales y la presencia de la especie hasta aquellos modelos poblacionales explícitos con una alta parametrización espacial que incluyen los procesos ecológicos y la estocasticidad. Las medidas tuvieron un desempeño uniforme en la clasificación de los diferentes escenarios de acuerdo a la gravedad, principalmente cuando la variación en el impacto fue causada por la cantidad de hábitat presente. Sin embargo, las medidas difirieron en la clasificación para los casos en los que las dinámicas de dispersión fueron significativas en la influencia de la persistencia metapoblacional. Los impactos de los escenarios sobre las especies con una habilidad reducida de dispersión estuvieron mejor caracterizados con el uso de modelos que capturaron explícitamente estos procesos. La capacidad metapoblacional proporcionó categorías de clasificación con la correlación más consistente a aquellas provenientes de los modelos ricos en datos y con una alta parametrización e incorporó información sobre la dispersión con un reducido costo adicional de cómputo y de datos. Nuestros resultados resaltan la importancia de la consideración explícita de la ecología de las especies, la configuración espacial del hábitat y la perturbación cuando se eligen los indicadores de la persistencia de una especie. Sugerimos que se usen estrategias híbridas que mezclen modelos simples y complejos para mejorar las evaluaciones realizadas a múltiples especies.


Assuntos
Benchmarking , Conservação dos Recursos Naturais , Ecossistema , Modelos Biológicos , Dinâmica Populacional
4.
Can J Anaesth ; 64(3): 296-307, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28050803

RESUMO

PURPOSE: This article describes the functioning of the international drug control system, its integration into national legislation and policy, and the collective impact on access to medicines. SOURCE: We conducted a review of the three international drug control conventions, peer-reviewed articles, and grey literature known to the authors that describes national and international drug control systems and their impact on access to controlled medicines. This review was supplemented with literature derived from a structured search of MEDLINE® for articles relating to medical uses of ketamine in low- and middle-income countries conducted to strengthen an advocacy campaign. We illustrate the impact of the drug control system on access to medicines through an analysis of current levels of availability of opioids in many countries as well as through a description of the ongoing advocacy work to ensure the availability of ketamine for medical care in low-income countries. PRINCIPAL FINDINGS: The complexity of the international drug control system, along with health providers' lack of knowledge regarding key provisions, presents a barrier to improving access to safe anesthesia care in low- and middle-income countries. Fifteen of the 46 essential medicines of potential relevance to perioperative care are listed under one or more of the schedules of the three international drug control conventions and, subsequently, are required to be under national controls, potentially decreasing their availability for medical use. CONCLUSION: Improving the capacity and quality of anesthesia care in low- and middle-income countries requires attention to improving access to controlled medicines. Anesthesiologists and others involved in global health work should collaborate with policymakers and others to improve national and international drug control legislation to ensure that attempts to thwart illicit drug trafficking and use do not compromise availability of controlled medicines.


Assuntos
Anestesia , Controle de Medicamentos e Entorpecentes , Países em Desenvolvimento , Humanos , Assistência Perioperatória , Procedimentos Cirúrgicos Operatórios
5.
Am J Primatol ; 78(4): 462-472, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26637802

RESUMO

Reliable assessments of species' status are prerequisites for monitoring the success of conservation programmes. However, survey conditions such as terrain and inaccessibility, compounded by the low densities of many species across Southeast Asia and other parts of the world are considerable barriers to obtaining robust populations estimates. We used an occupancy-based approach and multi-model inference to generate occupancy and abundance estimates for northern white-cheeked crested gibbons Nomascus leucogenys and southern white-cheeked crested gibbons N. siki in the Nam Kading National Protected Area (NKNPA) in central Lao Peoples' Democratic Republic (hereafter Laos). We present these estimates for gibbons within the context of a strategy designed to monitor multiple species and discuss the practical challenges to obtaining sufficient data for robust population estimates to detect change in gibbon status over time. We surveyed approximately 210 km2 of habitat and estimate an abundance of 45 (SE = 17, CV = 37%) groups, giving an average site abundance of 0.21 (SE = 0.08, CV = 37%) groups per km2 . We make recommendations for ongoing gibbon monitoring and discuss the wider implications for cost effective wildlife monitoring in Laos. Am. J. Primatol. 78:462-472, 2016. © 2015 Wiley Periodicals, Inc.

6.
Drug Alcohol Rev ; 32(6): 566-73, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24118500

RESUMO

INTRODUCTION AND AIMS: The study investigates patients' pre-treatment expectations of, and post-treatment satisfaction with, supervised injectable opiate treatment delivered within UK's first such clinics within the Randomised Injectable Opiate Treatment Trial (RIOTT) (ISRCTN0133807). DESIGN AND METHODS: Data were collected from 127 chronic heroin addicts recruited to RIOTT and randomised to receive supervised injectable (heroin or methadone) treatment or optimised oral maintenance treatment at supervised injectable maintenance clinics in London, Darlington and Brighton. RESULTS: Of 127 RIOTT patients, 113 (89%) provided responses to structured enquiry about treatment expectations, and 94 (74%) subsequent responses about treatment satisfaction (at six months). Patients were hoping that injectable heroin treatment would: reduce substance misuse (81%); help achieve normality, routine and structure (16%); and increase education and work prospects (15%). At six months, an area of treatment satisfaction most commonly reported by all three trial groups was reduced substance misuse (supervised injectable heroin 59%, supervised injectable methadone 56%, optimised oral methadone 54%). Most found supervision acceptable, but some desired modifications were also identified. DISCUSSION AND CONCLUSIONS: Patients previously considered non-responsive to treatment appear to have similar treatment expectations and aspirations as other drug users in treatment. Supervised injectable opioid treatment patients consistently reported treatment satisfaction but also that more could be done to optimise aspects of current arrangement. This raised the challenging issue of the extent to which opinions of patients need to be taken into consideration in shaping future treatment provision. Future research may need to examine the extent of expectations 'fit' and the relationship between treatment sought and received.


Assuntos
Dependência de Heroína/reabilitação , Heroína/administração & dosagem , Metadona/administração & dosagem , Programas de Troca de Agulhas , Satisfação do Paciente , Administração Oral , Adulto , Feminino , Seguimentos , Dependência de Heroína/psicologia , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Reino Unido
8.
Harm Reduct J ; 3: 28, 2006 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-17002810

RESUMO

Whilst unsupervised injectable methadone and diamorphine treatment has been part of the British treatment system for decades, the numbers receiving injectable opioid treatment (IOT) has been steadily diminishing in recent years. In contrast, there has been a recent expansion of supervised injectable diamorphine programs under trial conditions in a number of European and North American cities, although the evidence regarding the safety, efficacy and cost effectiveness of this treatment approach remains equivocal. Recent British clinical guidance indicates that IOT should be a second-line treatment for those patients in high-quality oral methadone treatment who continue to regularly inject heroin, and that treatment be initiated in newly-developed supervised injecting clinics. The Randomised Injectable Opioid Treatment Trial (RIOTT) is a multisite, prospective open-label randomised controlled trial (RCT) examining the role of treatment with injected opioids (methadone and heroin) for the management of heroin dependence in patients not responding to conventional substitution treatment. Specifically, the study examines whether efforts should be made to optimise methadone treatment for such patients (e.g. regular attendance, supervised dosing, high oral doses, access to psychosocial services), or whether such patients should be treated with injected methadone or heroin. Eligible patients (in oral substitution treatment and injecting illicit heroin on a regular basis) are randomised to one of three conditions: (1) optimized oral methadone treatment (Control group); (2) injected methadone treatment; or (3) injected heroin treatment (with access to oral methadone doses). Subjects are followed up for 6-months, with between-group comparisons on an intention-to-treat basis across a range of outcome measures. The primary outcome is the proportion of patients who discontinue regular illicit heroin use (operationalised as providing >50% urine drug screens negative for markers of illicit heroin in months 4 to 6). Secondary outcomes include measures of other drug use, injecting practices, health and psychosocial functioning, criminal activity, patient satisfaction and incremental cost effectiveness. The study aims to recruit 150 subjects, with 50 patients per group, and is to be conducted in supervised injecting clinics across England.

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