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There are many large, easy‐to‐observe anseriform birds (ducks, geese, and swans) in northern Australia and New Guinea and they often gather in large numbers. Yet, the structure of their populations and their regional movements are poorly understood. Lack of understanding of population structure limits our capacity to understand source‐sink dynamics relevant to their conservation or assess risks associated with avian‐borne pathogens, in particular, avian influenza for which waterfowl are the main reservoir species. We set out to assess present‐day genetic connectivity between populations of two widely distributed waterfowl in the Australo‐Papuan tropics, magpie goose Anseranas semipalmata (Latham, 1798) and wandering whistling‐duck Dendrocygna arcuata (Horsfield, 1824). Microsatellite data were obtained from 237 magpie geese and 64 wandering whistling‐duck. Samples were collected across northern Australia, and at one site each in New Guinea and Timor Leste. In the wandering whistling‐duck, genetic diversity was significantly apportioned by region and sampling location. For this species, the best model of population structure was New Guinea as the source population for all other populations. One remarkable result for this species was genetic separation of two flocks sampled contemporaneously on Cape York Peninsula only a few kilometers apart. In contrast, evidence for population structure was much weaker in the magpie goose, and Cape York as the source population provided the best fit to the observed structure. The fine scale genetic structure observed in wandering whistling‐duck and magpie goose is consistent with earlier suggestions that the west‐coast of Cape York Peninsula is a flyway for Australo‐Papuan anseriforms between Australia and New Guinea across Torres Strait.  相似文献   

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Wu B  Miao Y  Bai Y  Ye M  Xu Y  Chen H  Shen J  Qiu Y 《PloS one》2012,7(4):e34588

Background

The aim of this research was to evaluate the economic outcomes of radiotherapy (RT), temozolomide (TMZ) and nitrosourea (NT) strategies for glioblastoma patients with different prognostic factors.

Methodology/Principal Findings

A Markov model was developed to track monthly patient transitions. Transition probabilities and utilities were derived primarily from published reports. Costs were estimated from the perspective of the Chinese healthcare system. The survival data with different prognostic factors were simulated using Weibull survival models. Costs over a 5-year period and quality-adjusted life years (QALYs) were estimated. Probabilistic sensitivity and one-way analyses were performed. The baseline analysis in the overall cohort showed that the TMZ strategy increased the cost and QALY relative to the RT strategy by $25,328.4 and 0.29, respectively; and the TMZ strategy increased the cost and QALY relative to the NT strategy by $23,906.5 and 0.25, respectively. Therefore, the incremental cost effectiveness ratio (ICER) per additional QALY of the TMZ strategy, relative to the RT strategy and the NT strategy, amounts to $87,940.6 and $94,968.3, respectively. Subgroups with more favorable prognostic factors achieved more health benefits with improved ICERs. Probabilistic sensitivity analyses confirmed that the TMZ strategy was not cost-effective. In general, the results were most sensitive to the cost of TMZ, which indicates that better outcomes could be achieved by decreasing the cost of TMZ.

Conclusions/Significance

In health resource-limited settings, TMZ is not a cost-effective option for glioblastoma patients. Selecting patients with more favorable prognostic factors increases the likelihood of cost-effectiveness.  相似文献   

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Most of the recent applications of mathematical optimisation theory to the optimal or other control of pests and infectious diseases are surveyed here. Comments are made on some of the difficulties encountered in solving the resulting mathematical problems and in applying the relevant conclusions to real biological systems. At the end of the survey some further problems are suggested whose study might give satisfaction to both mathematicians and those interested in the practical problems of controlling biological populations.  相似文献   

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OBJECTIVE--To assess the sensitivity to within person change over time of an outcome measure for practitioners in primary care that is applicable to a wide range of illness. DESIGN--Comparison of a new patient generated instrument, the measure yourself medical outcome profile (MYMOP), with the SF-36 health profile and a five point change score; all scales were completed during the consultation with'' practitioners and repeated after four weeks. 103 patients were followed up for 16 weeks and their results charted; seven practitioners were interviewed. SETTING--Established practice of the four NHS general practitioners and four of the private complementary practitioners working in one medical centre. SUBJECTS--Systematic sample of 218 patients from general practice and all 47 patients of complementary practitioners; patients had had symptoms for more than seven days. OUTCOME MEASURES--Standardised response mean and index of responsiveness; view of practitioners. RESULTS--The index of responsiveness, relating to the minimal clinically important difference, was high for MYMOP: 1.4 for the first symptom, 1.33 for activity, and 0.85 for the profile compared with < 0.45 for SF-36. MYMOP''s validity was supported by significant correlation between the change score and the change in the MYMOP score and the ability of this instrument to detect more improvement in acute than in chronic conditions. Practitioners found that MYMOP was practical and applicable to all patients with symptoms and that its use increased their awareness of patients'' priorities. CONCLUSION--MYMOP shows promise as an outcome measure for primary care and for complementary treatment. It is more sensitive to change than the SF-36 and has the added bonus of improving patient-practitioner communication.  相似文献   

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Tropical countries are endowed with a rich array of biotic and geophysical resources. Only in the past 30 years has the rate of their resource transformation been so rapid as to threaten the environment, largely because of the demands of a growing human population resulting from the demographic transition. While resource transformations have produced the goods and services necessary to meet the needs of the growing populations, they have also generated a variety of effects on the environment and the societies of these countries. The rapid pace of technological advances and social change seriously threaten the sustainability of natural assets and ecological processes in these countries, with global consequences. This threat is exacerbated (1) by inadequate capability in these tropical countries to manage degradations in natural resources and the environment arising from technological interventions affecting large-scale ecological processes; and (2) by the coincidence of down-turns in long-term cycles of unequal amplitudes, which concern elitism and administrations, dependency on fossil fuels for industrialisation and shifts in cultural periods, all of which threaten the global structure and continuity of prevailing social institutions, Both phenomena endanger the prospects for international investments in the transformation of natural resources and management of the environment for sustainable livelihoods, especially in developing countries. most tropical countries have developing economies, and have inadequate capacity to manage the impacts and trade-offs of technological insertions largely because of financial constraints, poor technical expertise and the international character of their economies. In spite of harsh socio-biological, technological and financial constraints, there is a pressing need for investing in human expertise in tropical countries because of their effects on the sustainability of global climate, resource and environmental heritage, cultural heritage and societal organisation. Assurance of this sustainability demands that investments in tropical countries must be founded on traditional knowledge, organisation and community participation; on comparative advantages in terms of resource endowments and technological skills; on strategies and actions promoting innovative futures; on the strengthening of institutional capacities for assessing impacts and trade-offs; on a universally-acceptable system for exchanging experiences about technological insertions with reference to spatial areas, levels of sophistication, assessment of impacts and standards; and on the attraction of various forms of international cooperation at professional, governmental and non-governmental levels, which has been recommended by the World Commission on Environment and Development (Bruntland Commission). This overall challenge for international development in the tropics amounts to advancing macro-ecological and-economic sciences of large-scale processes having local impacts, andvice versa, involving the dynamic interactions between culture and philosophy, politics, investment (economics), society, technology and environment at different spatial and temporal scales.  相似文献   

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A major global effort to enable cost‐effective natural regeneration is needed to achieve ambitious forest and landscape restoration goals. Natural forest regeneration can potentially play a major role in large‐scale landscape restoration in tropical regions. Here, we focus on the conditions that favor natural regeneration within tropical forest landscapes. We illustrate cases where large‐scale natural regeneration followed forest clearing and non‐forest land use, and describe the social and ecological factors that drove these local forest transitions. The self‐organizing processes that create naturally regenerating forests and natural regeneration in planted forests promote local genetic adaptation, foster native species with known traditional uses, create spatial and temporal heterogeneity, and sustain local biodiversity and biotic interactions. These features confer greater ecosystem resilience in the face of future shocks and disturbances. We discuss economic, social, and legal issues that challenge natural regeneration in tropical landscapes. We conclude by suggesting ways to enable natural regeneration to become an effective tool for implementing large‐scale forest and landscape restoration. Major research and policy priorities include: identifying and modeling the ecological and economic conditions where natural regeneration is a viable and favorable land‐use option, developing monitoring protocols for natural regeneration that can be carried out by local communities, and developing enabling incentives, governance structures, and regulatory conditions that promote the stewardship of naturally regenerating forests. Aligning restoration goals and practices with natural regeneration can achieve the best possible outcome for achieving multiple social and environmental benefits at minimal cost.  相似文献   

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Glaucoma is a progressive disease due to damage in the optic nerve with associated functional losses. Although the relationship between structural and functional progression in glaucoma is well established, there is disagreement on how this association evolves over time. In addressing this issue, we propose a new class of non‐Gaussian linear‐mixed models to estimate the correlations among subject‐specific effects in multivariate longitudinal studies with a skewed distribution of random effects, to be used in a study of glaucoma. This class provides an efficient estimation of subject‐specific effects by modeling the skewed random effects through the log‐gamma distribution. It also provides more reliable estimates of the correlations between the random effects. To validate the log‐gamma assumption against the usual normality assumption of the random effects, we propose a lack‐of‐fit test using the profile likelihood function of the shape parameter. We apply this method to data from a prospective observation study, the Diagnostic Innovations in Glaucoma Study, to present a statistically significant association between structural and functional change rates that leads to a better understanding of the progression of glaucoma over time.  相似文献   

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OBJECTIVE--To develop general practice profiles of needs and demand for primary health care. DESIGN--Postal survey of a stratified random sample of 3478 people registered with five general practices. Data from a single practice were compared with data from the remaining four to identify areas of comparative need. SETTING--Five general practices in Lothian. MAIN OUTCOME MEASURES--Differences between the single practice and the comparison practices in terms of social and economic circumstances, limiting long term illness, specific ongoing conditions, minor illness or symptoms, psychosocial problems, discussion of lifestyle, associated use of services. RESULTS--Respondents from the single practice reported higher rates than those in the four comparison practices of ongoing mental health and respiratory problems and use of antidepressants, tranquillisers, or sleeping tablets. Although rates of limiting long term illness and other specific ongoing conditions were comparable, the rates of minor illness or symptoms and psychosocial difficulties were higher in the single practice. Respondents from the single practice were more likely to consult frequently, to have contacted the practice out of normal working hours, and to have discussed psychosocial difficulties with a general practitioner. For any specific ongoing condition or "minor" illness, respondents from the single practice were no more likely to consult. CONCLUSIONS--A comparative survey approach is a useful method of developing an understanding of patterns of need and demand among general practice populations. It has the potential to inform planning within individual general practices and the process of commissioning among general practices within a given area.  相似文献   

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BackgroundRosacea is a chronic inflammatory disorder affecting millions of individuals worldwide. Diagnosis is based on signs and symptoms with management and treatment aimed to suppress inflammatory lesions, erythema, and telangiectasia. While many clinical trials of rosacea exist, the lack of consensus in outcome reporting across all trials poses a concern. Proper evaluation and comparison of treatment modalities is challenging. In order to address the inconsistencies present, this project aims to determine a core set of outcomes which should be evaluated in all clinical trials of rosacea.Methods/designThis project will utilize a methodology similar to previous core outcome set research. A long list of outcomes will be extracted over four phases: (1) systematic literature review, (2) patient interviews, (3) other published sources, and (4) stakeholder involvement. Potential outcomes will be examined by the Steering Committee to provide further insight. The Delphi process will then be performed to prioritize and condense the list of outcomes generated. Two homogenous groups of physicians and patients will participate in two consecutive rounds of Delphi surveys. A consensus meeting, composed of physicians, patients, and stakeholders, will be conducted after the Delphi exercise to further select outcomes, taking into account participant scores. By the end of the meeting, members will vote and decide on a final recommended set of core outcomes. For the duration of the study, we will be in collaboration with both the Core Outcome Measures in Effectiveness Trials (COMET) and Cochrane Skin Group - Core Outcome Set Initiative (CSG-COUSIN).DiscussionThis study aims to develop a core outcome set to guide assessment in clinical trials of rosacea. The end-goal is to improve the reliability and consistency of outcome reporting, thereby allowing sufficient evaluation of treatment effectiveness and patient satisfaction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1554-3) contains supplementary material, which is available to authorized users.  相似文献   

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