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Protected area managers have limited resources and so need fine-scale information to decide where to focus their budgets for law enforcement and community outreach. This study used satellite imagery to map and analyse forest loss in an area that overlaps with Kerinci Seblat National Park, Sumatra, to identify areas most susceptible to illegal logging. Between 1985 and 1992, forest located at lower elevation and close to roads was most vulnerable to clearance. These factors were also significant between 1992 and 1999, along with distance to newly created logging roads. The presence of these roads probably explained why the deforestation rate increased from 1.1% per year to 3.0% per year over the two study periods. The accuracy of the 1985–1992 model was measured in the field and successfully predicted subsequent deforestation patterns, suggesting that this methodology could be used to identify where future patrolling effort and community outreach programmes should be focussed. In addition, this approach could be used more widely in conservation planning to prioritise the protection of vulnerable sites.  相似文献   

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BackgroundVisceral Leishmaniasis (VL) is endemic in South Sudan, manifesting periodically in major outbreaks. Provision of treatment during endemic periods and as an emergency response is impeded by instability and conflict. Médecins Sans Frontières (MSF) has provided health care in South Sudan since the late 1980’s, including treatment for 67,000 VL patients. In recent years, MSF monitoring data have indicated increasing numbers of VL relapse cases. A retrospective analysis of these data was performed in order to provide insight into the possible causes of this increase.Methodology/Principal findingsProgramme monitoring data from the MSF hospital in Lankien, Jonglei State, South Sudan, for the period 2001–2018 were analysed to detect trends in VL relapse as a proportion of all VL cases presenting to MSF treatment centres. Routinely collected patient-level data from relapse and primary VL cases treated at all MSF sites in South Sudan over the same period were analysed to describe patient characteristics and treatments received. VL relapse as a proportion of all VL cases increased by 6.5% per annum (95% CI 0.3% to 13.0%, p = 0.04), from 5.2% during 2001–2003 to 14.4% during 2016–2018. Primary VL and VL relapse patients had similar age, sex and anthropometric characteristics, the latter indicating high indices of undernutrition which were relatively constant over time. Clinical factors (Hb, spleen size, and VL severity score) also did not vary substantially over time. SSG/PM was the main treatment regimen from 2001–2018, used in 68.7% of primary and 70.9% of relapse VL cases; AmBisome was introduced in 2013, received by 22.5% of primary VL and 32.6% of VL relapse cases from 2013–2018.ConclusionIncreasing incidence of VL relapse in South Sudan does not appear to be explained by changes in patient characteristics or other factors. Our data are concerning and may indicate an emergence of treatment-resistant parasite strains, decreasing the effectiveness of treatment regimens. This warrants further investigation as a causal factor. New chemical entities that will enable safe and highly effective short-course oral treatments for VL are urgently needed.  相似文献   

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Key to the success of orangutan conservation management practices is the prevention of the introduction of infectious diseases to the remaining populations. Previous reports of Entamoeba spp. positive orangutans are of concern as Entamoeba spp. infection has been linked to morbidity and mortality in primates. It remains to be determined if the Entamoeba species infecting orangutans is the pathogenic Entamoeba histolytica. Orangutan fecal samples have been collected from orangutans from sites in Sumatra (Bukit Lawang, Ketambe, and Suaq, 241 samples from 64 individuals), and two sites in Kalimantan (Sebangau and Tuanan, 129 samples from 39 individuals). All samples were from wild orangutans except for a proportion from Sumatra which were from semi-wild (108 samples, 10 individuals). E. histolytica-specific nested PCR assays were carried out on the fecal samples. A total of 36 samples from 17 individuals tested positive for E. histolytica. When compared with published sequences using NCBI BLAST the E. histolytica positive samples showed a 98–99% concordance. The majority (76%, n = 36) of the positive isolates came from semi-wild orangutans in Bukit Lawang. This study supports the growing body of evidence that contact with humans is an important risk factor for infection of wild primates with E. histolytica.  相似文献   

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Peatlands in Indonesia are of global significance for biodiversity conservation and climate regulation, as well as of national and local significance for water management and livelihood support. Despite their importance, in tropics these ecosystems remain among the least investigated and monitored and are increasingly threatened by anthropogenic activities.To support the ongoing formulation, refinement and implementation of peatland restoration and conservation activities in Indonesia, we developed a methodology based on land cover and land productivity analysis, which will help prioritize interventions in Sumatra, Kalimantan and Papua.Results showed that of the analysed peatland area, approximately 45.5% should be conserved, 28.7% should be restored and 16.2% should be subjected to sustainable agricultural practices. Furthermore, the analysis showed that only 15.6% of the peatlands in need of conservation measures are currently protected, resulting in a necessary expansion of protected areas of about 84%.This study is intended as a tool for policy makers to guide future action, emphasising that conservation and restoration efforts in Indonesian peatlands should be increased, and providing spatial guidance for their implementation.  相似文献   

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Influenza is one of the major respiratory diseases in humans. Macau is a tourist city with high density of population and special population mobility. The study on the epidemiological characteristics of influenza in Macau should bring great value for preventing influenza in tourist cities like Macau in the world. In this study, we collected a total of 104,874 samples with influenza-like illness (ILI) in Macau from 2010 to 2018. Chi-square test and binary multivariable logistic regression were used to investigate the epidemiological characteristics of influenza A and B in Macau. Among these ILI samples, the overall positive rate is 17.17% for influenza A and 6.97% for influenza B. The epidemics of influenza in three years (i.e., 2012, 2017 and 2018) differ from the remaining years (i.e., normal years). In a normal year, influenza A occurs year-round whereas influenza B is seasonal. Our research shows significant differences in influenza infections between different age groups in normal years. Interestingly, our analysis shows no significant difference between locals and tourists in influenza A and B infection in a normal year, whereas the odds of influenza A in tourists were significantly higher than those in locals in July 2017 and the odds of influenza B in tourists were significantly higher than those in locals in January–February 2012 and January–February 2018. This is possibly attributed by the policy of free vaccination to everyone in Macau. These findings should be valuable for preventing influenza in not only Macau but also the world.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12250-021-00388-6.  相似文献   

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The dispersal efficiency and potential distribution of ornithochorous seeds of Elaeagnus umbellata in a riparian habitat were evaluated to clarify this species' establishment site in relation to the disturbance regime of the floodplain. Fruit removal by avian frugivores was monitored using fruit bags, and the spatial distribution of excreted seeds was quantified by seed traps set randomly on a gravel bar as an isolated seed source in the Yoshino River throughout an autumn fruiting season. Although more than 45% of the fruits remained on the twigs in the fruit bags, almost all fruits on the control twigs without fruit bags were exploited by the beginning of January. The fruit removal rate and seed dispersal distance were positively correlated with an increase in wintering bird species and their abundance. Intact bird‐dispersed seeds of E. umbellata were trapped within a 400‐m range and damaged seeds were limited to traps set within 50 m from the seed source. Frugivore behavior, such as feces excretion on rocks near water drinking sites and perching on surrounding woodland, greatly influenced the spatial and temporal dispersal pattern of the seed rain. In the present study, the avian frugivores showed upstream seed dispersal; thus, in years with stochastic autumnal floods, secondary dispersal via hydrochory downstream may be facilitated. The intensive seed dispersal in E. umbellata indicates that the present distribution of parent trees in the restricted elevation range of the gravel bars is the result of survival through disturbance, rather than seed dispersal limitation.  相似文献   

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BackgroundJapanese encephalitis (JE) is a mosquito-borne disease and associated with high mortality and disability rate among symptomatic cases. In the absence of local data, this study estimated the economic burden and the disability-adjusted life years (DALYs) due to JE in Zhejiang Province, China during 2013–2018, to increase disease awareness and provide evidence for effective health policy.Methodology/Principle findingsWe merged multiple data sources, including National Notifiable Disease Registry System (NNDRS), patient interviews and medical records from corresponding hospitals for JE cases which occurred during 2013–2018 in Zhejiang Province. Direct costs were extracted from hospitals’ billing systems and patient interviews. Indirect costs and disease burden were calculated based on questionnaire survey from patient interviews and follow-up assessment by general practitioners. Given under-reporting, an expansion factor (EF) was applied to extrapolate the JE burden to the provincial level. The total economic burden of JE during 2013–2018 was estimated at US $12.01 million with an EF = 3. Of this, $8.32 million was due to direct economic cost and $3.69 million to indirect cost. The disease burden of JE was 42.75 DALYs per million population (28.44 YLD, 14.28 YLL) according to the 1990 Global Burden of Disease (GBD 1990) methodology and 80.01 DALYs (53.67YLD, 26.34YLL) according to the GBD 2010 methodology. Sensitivity analysis demonstrated that the overall economic burden varied from US$ 1.73–36.42 million. The greatest variation was due to the prognosis of illness (-85.57%-203.17%), followed by occupation (-34.07%-134.12%) and age (-72.97%-47.69%).Conclusions/SignificanceJE imposes a heavy burden for families and society in Zhejiang Province. This study provides comprehensive empirical estimates of JE burden to increase awareness and strengthen knowledge of the public. These data may support provincial level public health decision making for prevention and control of JE. Ongoing surveillance for acute meningitis and encephalitis syndrome (AEMS) in sentinel hospitals, is needed to further refine estimates of JE burden.  相似文献   

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BackgroundAnthrax is a disease that affects humans and animals. In Ethiopia, anthrax is a reportable disease and assumed to be endemic, although laboratory confirmation has not been routinely performed until recently. We describe the findings from the investigation of two outbreaks in Amhara region.MethodsFollowing reports of suspected outbreaks in Wag Hamra zone (Outbreak 1) and South Gondar zone (Outbreak 2), multi-sectoral teams involving both animal and public health officials were deployed to investigate and establish control programs. A suspect case was defined as: sudden death with rapid bloating or bleeding from orifice(s) with unclotted blood (animals); and signs compatible with cutaneous, ingestion, or inhalation anthrax ≤7 days after exposure to a suspect animal (humans). Suspect human cases were interviewed using a standard questionnaire. Samples were collected from humans with suspected anthrax (Outbreak 1 and Outbreak 2) as well as dried meat of suspect animal cases (Outbreak 2). A case was confirmed if a positive test was returned using real-time polymerase chain reaction (qPCR).ResultsIn Outbreak 1, a total of 49 cows died due to suspected anthrax and 22 humans developed symptoms consistent with cutaneous anthrax (40% attack rate), two of whom died due to suspected ingestion anthrax. Three people were confirmed to have anthrax by qPCR. In Outbreak 2, anthrax was suspected to have caused the deaths of two livestock animals and one human. Subsequent investigation revealed 18 suspected cases of cutaneous anthrax in humans (27% attack rate). None of the 12 human samples collected tested positive, however, a swab taken from the dried meat of one animal case (goat) was positive by qPCR.ConclusionWe report the first qPCR-confirmed outbreaks of anthrax in Ethiopia. Both outbreaks were controlled through active case finding, carcass management, ring vaccination of livestock, training of health professionals and outreach with livestock owners. Human and animal health authorities should work together using a One Health approach to improve case reporting and vaccine coverage.  相似文献   

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The Arctic Ocean is undergoing rapid transformation toward a seasonally ice‐free ecosystem. As ice‐adapted apex predators, polar bears (Ursus maritimus) are challenged to cope with ongoing habitat degradation and changes in their prey base driven by food‐web response to climate warming. Knowledge of polar bear response to environmental change is necessary to understand ecosystem dynamics and inform conservation decisions. In the southern Beaufort Sea (SBS) of Alaska and western Canada, sea ice extent has declined since satellite observations began in 1979 and available evidence suggests that the carrying capacity of the SBS for polar bears has trended lower for nearly two decades. In this study, we investigated the population dynamics of polar bears in Alaska''s SBS from 2001 to 2016 using a multistate Cormack–Jolly–Seber mark–recapture model. States were defined as geographic regions, and we used location data from mark–recapture observations and satellite‐telemetered bears to model transitions between states and thereby explain heterogeneity in recapture probabilities. Our results corroborate prior findings that the SBS subpopulation experienced low survival from 2003 to 2006. Survival improved modestly from 2006 to 2008 and afterward rebounded to comparatively high levels for the remainder of the study, except in 2012. Abundance moved in concert with survival throughout the study period, declining substantially from 2003 and 2006 and afterward fluctuating with lower variation around an average of 565 bears (95% Bayesian credible interval [340, 920]) through 2015. Even though abundance was comparatively stable and without sustained trend from 2006 to 2015, polar bears in the Alaska SBS were less abundant over that period than at any time since passage of the U.S. Marine Mammal Protection Act. The potential for recovery is likely limited by the degree of habitat degradation the subpopulation has experienced, and future reductions in carrying capacity are expected given current projections for continued climate warming.  相似文献   

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Liquid–liquid phase separation (LLPS) facilitates the formation of membraneless compartments in a cell and allows the spatiotemporal organization of biochemical reactions by concentrating macromolecules locally. In plants, LLPS defines cellular reaction hotspots, and stimulus‐responsive LLPS is tightly linked to a variety of cellular and biological functions triggered by exposure to various internal and external stimuli, such as stress responses, hormone signaling, and temperature sensing. Here, we provide an overview of the current understanding of physicochemical forces and molecular factors that drive LLPS in plant cells. We illustrate how the biochemical features of cellular condensates contribute to their biological functions. Additionally, we highlight major challenges for the comprehensive understanding of biological LLPS, especially in view of the dynamic and robust organization of biochemical reactions underlying plastic responses to environmental fluctuations in plants.  相似文献   

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Ecosystem engineers are organisms that directly or indirectly control the availability of resources to other organisms by causing physical state changes in biotic or abiotic materials. Termites (Insecta, Isoptera) are among the most important ecosystem engineers in tropical ecosystems. We used a field experiment in the tall grasslands of Serengeti National Park, Tanzania, to investigate 1) the consumption by termites of grass litter and dung baits along the landscape gradient of catena position, and 2) seasonal variation in litter and dung removal. Our maps of termitaria and patterns of bait removal revealed clear spatial and temporal hotspots of termite activity. In the dry season termites removed more baits at the top‐catena positions than at the bottom positions, but there was no effect of catena position in the wet season. Spatial hotspots of termite activity overlapped with those of both mammalian herbivores and predators. Within the framework of ecosystem engineering, this study suggests that intraspecific aspects of spatial heterogeneity and temporal variability deserve much greater consideration.  相似文献   

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Zika virus (ZIKV) and chikungunya virus (CHIKV) were recently introduced into the Americas resulting in significant disease burdens. Understanding their spatial and temporal dynamics at the subnational level is key to informing surveillance and preparedness for future epidemics. We analyzed anonymized line list data on approximately 105,000 Zika virus disease and 412,000 chikungunya fever suspected and laboratory-confirmed cases during the 2014–2017 epidemics. We first determined the week of invasion in each city. Out of 1,122, 288 cities met criteria for epidemic invasion by ZIKV and 338 cities by CHIKV. We analyzed risk factors for invasion using linear and logistic regression models. We also estimated that the geographic origin of both epidemics was located in Barranquilla, north Colombia. We assessed the spatial and temporal invasion dynamics of both viruses to analyze transmission between cities using a suite of (i) gravity models, (ii) Stouffer’s rank models, and (iii) radiation models with two types of distance metrics, geographic distance and travel time between cities. Invasion risk was best captured by a gravity model when accounting for geographic distance and intermediate levels of density dependence; Stouffer’s rank model with geographic distance performed similarly well. Although a few long-distance invasion events occurred at the beginning of the epidemics, an estimated distance power of 1.7 (95% CrI: 1.5–2.0) from the gravity models suggests that spatial spread was primarily driven by short-distance transmission. Similarities between the epidemics were highlighted by jointly fitted models, which were preferred over individual models when the transmission intensity was allowed to vary across arboviruses. However, ZIKV spread considerably faster than CHIKV.  相似文献   

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估算参考作物蒸散量(ET0)有助于揭示流域的水热平衡和水循环过程,为合理利用与开发流域水资源提供基础。本研究通过重新拟合研究区的净短波辐射系数,使用改进后的Penman-Monteith模型,计算1965—2018年广西西江流域的ET0,使用Mann-Kendall法对ET0进行趋势分析与突变点检测,用反距离权重法插值后分析ET0时空演变特征,根据气候因子的贡献率判断ET0的影响因子。结果表明:在空间上,ET0呈现随海拔降低而增加的趋势,其高值主要位于流域中部地区,而低值位于西北侧的云贵高原边缘及斜坡带,春季ET0呈现出经度梯度性,夏季ET0与年际的空间格局类似;在时间上,流域年均ET0为637.2mm,增长率为-0.018 mm·a-1,整体呈微弱的下降趋势。除春季(0.053 mm·a-1)呈上升趋势外,夏季(-0.053 mm·a-...  相似文献   

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The RAD9–RAD1–HUS1 (9–1–1) clamp forms one half of the DNA damage checkpoint system that signals the presence of substantial regions of single-stranded DNA arising from replication fork collapse or resection of DNA double strand breaks. Loaded at the 5′-recessed end of a dsDNA–ssDNA junction by the RAD17–RFC clamp loader complex, the phosphorylated C-terminal tail of the RAD9 subunit of 9–1–1 engages with the mediator scaffold TOPBP1 which in turn activates the ATR kinase, localised through the interaction of its constitutive partner ATRIP with RPA-coated ssDNA. Using cryogenic electron microscopy (cryoEM) we have determined the structure of a complex of the human RAD17–RFC clamp loader bound to human 9–1–1, engaged with a dsDNA–ssDNA junction. The structure answers the key questions of how RAD17 confers specificity for 9–1–1 over PCNA, and how the clamp loader specifically recognises the recessed 5′ DNA end and fixes the orientation of 9–1–1 on the ssDNA.  相似文献   

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Our study investigates the epidemiology of Down syndrome (DS) in the state of Ohio during the 1970s. The occurrence of DS births was examined to learn if statistically significant temporal variation was present among these data. Both monthly and annual numbers of DS births, adjusted for changing numbers of live births, were tested for such variation; furthermore, the data were analyzed for cyclic variation by attempting to fit simple trigonometric functions to the data.

Individuals with DS were ascertained using the records of cytogenetics laboratories and birth certificate records. Demographic data such as race, date of birth, and maternal age were collected on these individuals using their birth certificates as the data source. Appropriate parallel live-birth data were obtained from the Ohio Department of Health. The total number of affected individuals ascertained was 1,364, 66.7% of the total estimated population size. The data analysis was restricted to whites only (1,203 individuals) because they represented a more homogeneous sample than the total.

Monthly and annual variation in the numbers of live births was removed by producing single-year maternal-age adjusted numbers of DS births using the total Ohio white live births as the reference population. Analysis of covariance using single-year maternal ages ≤ 16 and ≥ 45 as the covariate was used to analyze the adjusted numbers of DS births for temporal variation.

No significant differences were detected among the annual adjusted numbers of DS births (P = .24), nor were there differences among the monthly adjusted numbers of DS (P = .37). The modes of ascertainment were tested to learn if there were annual or monthly differences in the method of ascertainment. No significant differences were detected for these data (P = .82 and P = .85, respectively). Furthermore, the data were separated into the maternal-age categories < 35 and ≥ 35, and annual and monthly adjusted DS births to these two maternal-age categories were examined for temporal variation. No significant differences were found among these data, P > .10 for all four of the tests. No simple cyclic functions were found to fit either the annual or monthly data.

The Ohio study reported here showed that through the use of a large sample, controlling for variation in the numbers of live births, and the use of detailed statistical tests, no significant temporal variation in the occurrence of DS births existed during the 1970s.

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