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Sample records for qinghai-tibetan plateau endemic

  1. (Bos grunniens) in Qinghai-Tibetan Plateau

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2012-10-30

    Oct 30, 2012 ... Qinghai-Tibetan Plateau, as it represents a unique bovine species adapted to ..... al., 1993; Udina et al., 2003), mastitis caused by. Staphylococcus sp. ... for prevention and treatment in many cases (Gerald et al., 2003). But in ...

  2. Mapping risk of plague in Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Qian, Quan; Zhao, Jian; Fang, Liqun; Zhou, Hang; Zhang, Wenyi; Wei, Lan; Yang, Hong; Yin, Wenwu; Cao, Wuchun; Li, Qun

    2014-07-10

    Qinghai-Tibetan Plateau of China is known to be the plague endemic region where marmot (Marmota himalayana) is the primary host. Human plague cases are relatively low incidence but high mortality, which presents unique surveillance and public health challenges, because early detection through surveillance may not always be feasible and infrequent clinical cases may be misdiagnosed. Based on plague surveillance data and environmental variables, Maxent was applied to model the presence probability of plague host. 75% occurrence points were randomly selected for training model, and the rest 25% points were used for model test and validation. Maxent model performance was measured as test gain and test AUC. The optimal probability cut-off value was chosen by maximizing training sensitivity and specificity simultaneously. We used field surveillance data in an ecological niche modeling (ENM) framework to depict spatial distribution of natural foci of plague in Qinghai-Tibetan Plateau. Most human-inhabited areas at risk of exposure to enzootic plague are distributed in the east and south of the Plateau. Elevation, temperature of land surface and normalized difference vegetation index play a large part in determining the distribution of the enzootic plague. This study provided a more detailed view of spatial pattern of enzootic plague and human-inhabited areas at risk of plague. The maps could help public health authorities decide where to perform plague surveillance and take preventive measures in Qinghai-Tibetan Plateau.

  3. Intense uplift of the Qinghai-Tibetan Plateau triggered rapid diversification of Phyllolobium (Leguminosae) in the Late Cenozoic

    Science.gov (United States)

    Ming-Li Zhang; Yun Kang; Yang Zhong; Stewart C. Sanderson

    2012-01-01

    Phyllolobium, a recently established genus from subgenus Pogonophace of Astragalus, contains about 20 species and four sections, mostly endemic to the Qinghai-Tibetan Plateau (QTP). The uplift of the QTP undoubtedly affected organismic evolution in the region, but further molecular dating in a phylogenetic context is required to test whether diversification is linked...

  4. Niche conservatism in Gynandropaa frogs on the southeastern Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Hu, Junhua; Broennimann, Olivier; Guisan, Antoine; Wang, Bin; Huang, Yan; Jiang, Jianping

    2016-09-07

    The role of ecological niche in lineage diversification has been the subject of long-standing interest of ecologists and evolutionary biologists. Gynandropaa frogs diversified into three independent clades endemic to the southeastern Qinghai-Tibetan Plateau. Here, we address the question whether these clades kept the same niche after separation, and what it tells us about possible diversification processes. We applied predictions in geographical (G)-space and tests of niche conservatism in environmental (E)-space. Niche models in G-space indicate separate regions with high suitability for the different clades, with some potential areas of sympatry. While the pair of central and eastern clades displayed the largest niche overlap for most variables, and strict niche equivalency was rejected for all clade-pairs, we found no strong evidence for niche divergence, but rather the signature of niche conservatism compared to null models in E-space. These results suggest a common ancestral ecological niche, and as such give good support to divergence through allopatric speciation, but alternative explanations are also possible. Our findings illustrate how testing for niche conservatism in lineage diversification can provide insights into underlying speciation processes, and how this information may guide further research and conservation practices, as illustrated here for amphibians on the Qinghai-Tibetan Plateau.

  5. Water chemistry in the rives of the permafrost regions on the eastern Qinghai-Tibetan Plateau

    Science.gov (United States)

    Wu, X.; Ma, X.; Ye, L.; Liu, G.

    2017-12-01

    Qinghai-Tibetan is the largest middle-low latitude permafrost areas on the world. There are several large rivers in the plateau, and the changes of the water resources of these rivers are associated with the water resource security of more than 1.35 billion people. Due to the high gradients, these rivers have a tremendous amount of potential energy for electricity output. To promote economic and social development and provide clean energy, hydropower development has taken place on several rivers which originate on the Qinghai-Tibetan Plateau. Since dam construction affect the flow velocity, water temperature, sediments delivery as well as organic matter and nitrogen, it is important to investigate the river chemistry in the head rivers of the reservoirs. We examined the water physio-chemical characteristics in the rivers under the typical vegetation types in the eastern Qinghai-Tibetan Plateau, and further analyzed their relationship to vegetation. The results showed that the total suspended sediment in the rivers were higher within the catchment of alpine steppe, with the lowest dissolved organic carbon content. In contrast, the rivers within the meadow had the highest dissolved organic carbon and lowest total suspension sediment. The dissolved organic carbon significantly positively correlated with the proportions of the meadow and wet meadow in the catchment. The pH, turbidity, and SUVA254 and dissolved organic carbon also correlated with each other. The results suggest that the vegetation type strongly affect the water chemistry in the permafrost regions on the Qinghai-Tibetan Plateau.

  6. Study on Sr-Nd isotopes of mesozoic-cenozoic granites in Qinghai-Tibetan plateau

    International Nuclear Information System (INIS)

    Qiu Ruizhao; Deng Jinfu; Zhou Su; Xiao Qinghui; Cai Zhiyong

    2003-01-01

    Mesozoic-Cenozoic magmatic activities were intensive in Qinghai-Tibetan plateau. Nd-Sr isotopic compositions of representative granitic plutons in western Qinghai-Tibetan plateau are reported in this paper. Combining with past isotopic data, which has reported in eastern Qinghai-Tibetan plateau, Sr-Nd isotopic compositions and material source and genesis of Mesozoic and Cenozoic granites in Qinghai-Tibetan plateau have been studied. The research result indicates there are three types of granite existing in Qinghai-Tibetan plateau, the granites of Late stage of Yanshan Period which distributing on north and south boundary of Gandes block (namely in north and south granitic belts of Dangdes) and cause of oceanic crust subduction, have ( 87 Sr/ 86 Sr)i of 0.7041-0.7064, ε (Nd) t of +2.5 - +5.7 and TDM age of 312-562 Ma, positive ε Nd, low ( 87 Sr/ 86 Sr)i ratio and young Nd model ages suggest relatively high contents of mantle-derived components in their sources, and this type granite might melt from subduction oceanic crust. The granites occurred intra-Gangdes block which were caused by collision of continent and post-collision, have ( 87 Sr/ 86 Sr)i of 0.706-0.719, ε (Nd) t of -5.3 - -8.3 and TDM age of 1323-1496 Ma, negative ε Nd, relative high ( 87 Sr/ 86 Sr)i ratio with an mid-Proterozoic Nd model ages, suggest granite has the mixing genesis of mantle-derived components and old crustal components in their sources. With relatively small variation range in ε (Nd) t and TDM age, it might imply granitic isotopic source in Gandes block to keep relative homogenization in long period. The granites in Himalayan block which there is not oceanic material to join in melting and to cause of intra-continental subduction, has most ( 87 Sr/ 86 Sr)i ratio more than 0.720, ε (Nd) t of -10.3 - -16.3 and TDM age of 1792-2206 Ma, high ( 87 Sr/ 86 Sr)i ratio, low negative ε (Nd)t with old Nd isotopic model ages and consistent with the Sr, Nd isotopic compositions of basement

  7. Snow effects on alpine vegetation in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Wang, Kun; Zhang, Li; Qiu, Yubao; Ji, Lei; Tian, Feng; Wang, Cuizhen; Wang, Zhiyong

    2013-01-01

    Understanding the relationships between snow and vegetation is important for interpretation of the responses of alpine ecosystems to climate changes. The Qinghai-Tibetan Plateau is regarded as an ideal area due to its undisturbed features with low population and relatively high snow cover. We used 500 m Moderate Resolution Imaging Spectroradiometer (MODIS) datasets during 2001–2010 to examine the snow–vegetation relationships, specifically, (1) the influence of snow melting date on vegetation green-up date and (2) the effects of snow cover duration on vegetation greenness. The results showed that the alpine vegetation responded strongly to snow phenology (i.e., snow melting date and snow cover duration) over large areas of the Qinghai-Tibetan Plateau. Snow melting date and vegetation green-up date were significantly correlated (p growth was influenced by different seasonal snow cover durations (SCDs) in different regions. Generally, the December–February and March–May SCDs played a significantly role in vegetation growth, both positively and negatively, depending on different water source regions. Snow's positive impact on vegetation was larger than the negative impact.

  8. Functional-trait ecology of the plateau pika Ochotona curzoniae (Hodgson, 1858) in the Qinghai-Tibetan Plateau ecosystem.

    Science.gov (United States)

    Smith, Andrew T; Badingqiuying; Wilson, Maxwell C; Hogan, Brigitte W

    2018-01-09

    Understanding a species' functional traits allows for a directed and productive perspective on the role a species plays in nature, thus its relative importance to conservation planning. The functional trait ecology of the plateau pika Ochotona curzoniae (Hodgson, 1858) is examined to better understand the resilience and sustainability of the high alpine grasslands of the Qinghai-Tibetan Plateau (QTP). The key functional traits of plateau pikas are their abundance and behavior of digging extensive burrow systems. Plateau pikas have been poisoned over a significant part of their original geographic distribution across the QTP, allowing comparison of ecological communities with and without pikas. Nearly all mammalian and avian carnivores, most of which are obligate predators on pikas, have been lost in regions where pikas have been poisoned. Most endemic birds on the QTP nest in pika burrows; when pikas are poisoned, burrows collapse, and these birds are greatly reduced in number. Due to the biopedturbation resulting from their burrows, regional plant species richness is higher in areas with pikas than without. The presence of pika burrows allows higher rates of infiltration during heavy monsoon rains compared to poisoned areas, possibly mitigating runoff and the potential for serious downslope erosion and flooding. Thus the functional traits of plateau pikas enhance native biodiversity and other important ecosystem functions; these traits are irreplaceable. As plateau pikas are not natural colonizers, active re-introduction programs are needed to restore pikas to areas from which they have been poisoned to restore the important functional ecological traits of pikas. This article is protected by copyright. All rights reserved.

  9. Radiocarbon reservoir between charred seeds and fish bone in Neolithic sites, northeastern Qinghai-Tibetan Plateau

    Science.gov (United States)

    Zhou, A.; Dong, G.; Ren, L.

    2017-12-01

    Many efforts have been done to understand the reservoir effect of Qinghai Lake, yet no agreement has been reached. Five archaeological sites, located around the junction between the estuary of Rivers and Qinghai Lake, are the earliest Neolithic Age sites in the Qinghai- Tibetan Plateau (QTP), which is critical for understanding patterns of prehistoric human inhabitation in the high plateau extreme environments. This study compares radiocarbon dates of fish bones and terrestrial plant remains uncovered from the same archaeological strata to see whether there was reservoir effect reference to reliable data. Results demonstrate that there were reservoir effects ranging from 300 to 600 years back to 3600 years ago, nevertheless, no reservoir was observed of the modern fish. Besides, stable isotopic analysis illustrated that modern fish consumed similar food to those of millennias ago.

  10. Vegetation greenness trend (2000 to 2009) and the climate controls in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Zhang, Li; Guo, Huadong; Ji, Lei; Lei, Liping; Wang, Cuizhen; Yan, Dongmei; Li, Bin; Li, Jing

    2013-01-01

    The Qinghai-Tibetan Plateau has been experiencing a distinct warming trend, and climate warming has a direct and quick impact on the alpine grassland ecosystem. We detected the greenness trend of the grasslands in the plateau using Moderate Resolution Imaging Spectroradiometer data from 2000 to 2009. Weather station data were used to explore the climatic drivers for vegetation greenness variations. The results demonstrated that the region-wide averaged normalized difference vegetation index (NDVI) increased at a rate of 0.036  yr−1. Approximately 20% of the vegetation areas, which were primarily located in the northeastern plateau, exhibited significant NDVI increase trend (p-value plateau. A strong positive relationship between NDVI and precipitation, especially in the northeastern plateau, suggested that precipitation was a favorable factor for the grassland NDVI. Negative correlations between NDVI and temperature, especially in the southern plateau, indicated that higher temperature adversely affected the grassland growth. Although a warming climate was expected to be beneficial to the vegetation growth in cold regions, the grasslands in the central and southwestern plateau showed a decrease in trends influenced by increased temperature coupled with decreased precipitation.

  11. Integrated assessment on the vulnerability of animal husbandry to snow disasters under climate change in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Wei, Yanqiang; Wang, Shijin; Fang, Yiping; Nawaz, Zain

    2017-10-01

    Animal husbandry is a dominant and traditional source of livelihood and income in the Qinghai-Tibetan Plateau. The Qinghai-Tibetan Plateau is the third largest snow covered area in China and is one of the main snow disaster regions in the world. It is thus imperative to urgently address the issue of vulnerability of the animal husbandry sector to snow disasters for disaster mitigation and adaptation under growing risk of these disasters as a result of future climate change. However, there is very few literature reported on the vulnerability of animal husbandry in the Qinghai-Tibetan Plateau. This assessment aims at identifying vulnerability of animal husbandry at spatial scale and to identify the reasons for vulnerability for adaptive planning and disaster mitigation. First, historical snow disaster characteristics have been analyzed and used for the spatial weight for vulnerability assessment. Second, indicator-based vulnerability assessment model and indicator system have been established. We combined risk of snow hazard, sensitivity of livestock to disaster, physical exposure to disaster, and community capacity to adapt to snow disaster in an integrated vulnerability index. Lastly, vulnerability of animal husbandry to snow disaster on the Qinghai-Tibetan Plateau has been evaluated. Results indicate that high vulnerabilities are mainly concentrated in the eastern and central plateau and that vulnerability decreases gradually from the east to the west. Due to global warming, the vulnerability trend has eased to some extent during the last few decades. High livestock density exposure to blizzard-prone regions and shortages of livestock barn and forage are the main reasons of high vulnerability. The conclusion emphasizes the important role of the local government and community to help local pastoralists for reducing vulnerability to snow disaster and frozen hazard. The approaches presented in this paper can be used for snow disaster mitigation, resilience

  12. Detours in long-distance migration across the Qinghai-Tibetan Plateau: individual consistency and habitat associations.

    Science.gov (United States)

    Liu, Dongping; Zhang, Guogang; Jiang, Hongxing; Lu, Jun

    2018-01-01

    Migratory birds often follow detours when confronted with ecological barriers, and understanding the extent and the underlying drivers of such detours can provide important insights into the associated cost to the annual energy budget and the migration strategies. The Qinghai-Tibetan Plateau is the most daunting geographical barrier for migratory birds because the partial pressure of oxygen is dramatically reduced and flight costs greatly increase. We analyzed the repeated migration detours and habitat associations of four Pallas's Gulls Larus ichthyaetus across the Qinghai-Tibetan Plateau over 22 migration seasons. Gulls exhibited notable detours, with the maximum distance being more than double that of the expected shortest route, that extended rather than reduced the passage across the plateau. The extent of longitudinal detours significantly increased with latitude, and detours were longer in autumn than in spring. Compared with the expected shortest routes, proximity to water bodies increased along autumn migration routes, but detour-habitat associations were weak along spring migration routes. Thus, habitat availability was likely one, but not the only, factor shaping the extent of detours, and migration routes were determined by different mechanisms between seasons. Significant between-individual variation but high individual consistency in migration timing and routes were revealed in both seasons, indicating a stronger influence of endogenous schedules than local environmental conditions. Gulls may benefit from repeated use of familiar routes and stopover sites, which may be particularly significant in the challenging environment of the Qinghai-Tibetan Plateau.

  13. Influences of climate change on area variation of Qinghai Lake on Qinghai-Tibetan Plateau since 1980s.

    Science.gov (United States)

    Tang, Lingyi; Duan, Xiaofang; Kong, Fanjin; Zhang, Fan; Zheng, Yangfan; Li, Zhen; Mei, Yi; Zhao, Yanwen; Hu, Shuijin

    2018-05-09

    Qinghai-Tibetan Plateau is the most sensitive region to global warming on Earth. Qinghai Lake, the largest lake on the plateau, has experienced evident area variation during the past several decades. To quantify the area changes of Qinghai Lake, a satellite-based survey based on Landsat images from the 1980s to 2010s has been performed. In addition, meteorological data from all the seven available stations on Qinghai-Tibetan Plateau has been analyzed. Area of Qinghai Lake shrank ~2% during 1987-2005, and then increased ~3% from 2005-2016. Meanwhile, the average annual temperature increased 0.319 °C/10 y in the past 50 years, where the value is 0.415 °C/10 y from 2005-2016. The structural equation modeling (SEM) shows that precipitation is the primary factor influencing the area of Qinghai Lake. Moreover, temperature might be tightly correlated with precipitation, snow line, and evaporation, thereby indirectly causes alternations of the lake area. This study elucidated the significant area variation of water body on the Qinghai-Tibetan Plateau under global warming since 1980s.

  14. Geochip-based analysis of microbial communities in alpine meadow soils in the Qinghai-Tibetan plateau.

    Science.gov (United States)

    Zhang, Yuguang; Lu, Zhenmei; Liu, Shanshan; Yang, Yunfeng; He, Zhili; Ren, Zuohua; Zhou, Jizhong; Li, Diqiang

    2013-03-29

    GeoChip 3.0, a microbial functional gene array, containing ~28,000 oligonucleotide probes and targeting ~57,000 sequences from 292 functional gene families, provided a powerful tool for researching microbial community structure in natural environments. The alpine meadow is a dominant plant community in the Qinghai-Tibetan plateau, hence it is important to profile the unique geographical flora and assess the response of the microbial communities to environmental variables. In this study, Geochip 3.0 was employed to understand the microbial functional gene diversity and structure, and metabolic potential and the major environmental factors in shaping microbial communities structure of alpine meadow soil in Qinghai-Tibetan Plateau. A total of 6143 microbial functional genes involved in carbon degradation, carbon fixation, methane oxidation and production, nitrogen cycling, phosphorus utilization, sulphur cycling, organic remediation, metal resistance, energy process and other category were detected in six soil samples and high diversity was observed. Interestingly, most of the detected genes associated with carbon degradation were derived from cultivated organisms. To identify major environmental factors in shaping microbial communities, Mantel test and CCA Statistical analyses were performed. The results indicated that altitude, C/N, pH and soil organic carbon were significantly (P the microbial functional structure and a total of 80.97% of the variation was significantly explained by altitude, C/N and pH. The C/N contributed 38.2% to microbial functional gene variation, which is in accordance with the hierarchical clustering of overall microbial functional genes. High overall functional genes and phylogenetic diversity of the alpine meadow soil microbial communities existed in the Qinghai-Tibetan Plateau. Most of the genes involved in carbon degradation were derived from characterized microbial groups. Microbial composition and structures variation were

  15. Topographic heterogeneity and temperature amplitude explain species richness patterns of birds in the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Zhang, Chunlan; Quan, Qing; Wu, Yongjie; Chen, Youhua; He, Peng; Qu, Yanhua; Lei, Fumin

    2017-04-01

    Large-scale patterns of species richness have gained much attention in recent years; however, the factors that drive high species richness are still controversial in local regions, especially in highly diversified montane regions. The Qinghai-Tibetan Plateau (QTP) and the surrounding mountains are biodiversity hot spots due to a high number of endemic montane species. Here, we explored the factors underlying this high level of diversity by studying the relationship between species richness and environmental variables. The richness patterns of 758 resident bird species were summarized at the scale of 1°×1° grid cell at different taxonomic levels (order, family, genus, and species) and in different taxonomic groups (Passeriformes, Galliformes, Falconiformes, and Columbiformes). These richness patterns were subsequently analyzed against habitat heterogeneity (topographical heterogeneity and land cover), temperature amplitude (annual temperature, annual precipitation, precipitation seasonality, and temperature seasonality) and a vegetation index (net primary productivity). Our results showed that the highest richness was found in the southeastern part of the QTP, the eastern Himalayas. The lowest richness was observed in the central plateau of the QTP. Topographical heterogeneity and temperature amplitude are the primary factors that explain overall patterns of species richness in the QTP, although the specific effect of each environmental variable varies between the different taxonomic groups depending on their own evolutionary histories and ecological requirements. High species richness in the southeastern QTP is mostly due to highly diversified habitat types and temperature zones along elevation gradients, whereas the low species richness in the central plateau of the QTP may be due to environmental and energetic constraints, as the central plateau is harsh environment.

  16. Patterns of species diversity and phylogenetic structure of vascular plants on the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Yan, Yujing; Yang, Xian; Tang, Zhiyao

    2013-11-01

    Large-scale patterns of species richness and the underlying mechanisms regulating these patterns have long been the central issues in biogeography and macroecology. Phylogenetic community structure is a result of combined effects of contemporary ecological interactions, environmental filtering, and evolutionary history, and it links community ecology with biogeography and trait evolution. The Qinghai-Tibetan Plateau provides a good opportunity to test the influence of contemporary climate on shaping species richness because of its unique geological history, cold climate, and high biodiversity. In this study, based on high-resolution distributions of ˜9000 vascular plant species, we explored how species richness and phylogenetic structure of vascular plants correlate with climates on the highest (and species rich) plateau on the Earth. The results showed that most of the vascular plants were distributed on the eastern part of the plateau; there was a strong association between species richness and climate, even after the effects of habitat heterogeneity were controlled. However, the responses of richness to climate remarkably depended on life-forms. Richness of woody plants showed stronger climatic associations than that of herbaceous plants; energy and water availability together regulated richness pattern of woody plants; whereas water availability predominantly regulated richness pattern of herbaceous plants. The phylogenetic structure of vascular species clustered in most areas of the plateau, suggesting that rapid speciation and environment filtering dominated the assembly of communities on the plateau. We further propose that biodiversity conservation in this area should better take into account ecological features for different life-forms and phylogenetic lineages.

  17. Shiga Toxin-Producing Escherichia coli in Plateau Pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Bai, Xiangning; Zhang, Wang; Tang, Xinyuan; Xin, Youquan; Xu, Yanmei; Sun, Hui; Luo, Xuelian; Pu, Ji; Xu, Jianguo; Xiong, Yanwen; Lu, Shan

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) are an emerging group of zoonotic pathogens. Ruminants are the natural reservoir of STEC. In this study we determined the prevalence and characteristics of the STEC in plateau pika (Ochotona curzoniae) on the Qinghai-Tibetan Plateau, China. A total of 1116 pika samples, including 294 intestinal contents samples, 317 fecal samples, and 505 intestinal contents samples, were collected from May to August in the years 2012, 2013, and 2015, respectively. Twenty-one samples (1.88%) yielded at least one STEC isolate; in total, 22 STEC isolates were recovered. Thirteen different O serogroups and 14 serotypes were identified. One stx 1 subtype (stx 1a) and three stx 2 subtypes (stx 2a, stx 2b, and stx 2d) were present in the STEC isolates. Fifteen, fourteen, and three STEC isolates harbored the virulence genes ehxA, subA, and astA, respectively. Adherence-associated genes iha and saa were, respectively, present in 72.73 and 68.18% of the STEC isolates. Twenty antibiotics were active against all the STEC isolates; all strains were resistant to penicillin G, and some to cephalothin or streptomycin. The 22 STEC isolates were divided into 16 pulsed-field gel electrophoresis patterns and 12 sequence types. Plateau pikas may play a role in the ongoing circulation of STEC in the Qinghai-Tibetan plateau. This study provides the first report on STEC in plateau pikas and new information about STEC reservoirs in wildlife. Based on the serotypes, virulence gene profiles and multi-locus sequence typing (MLST) analysis, the majority of these pika STECs may pose a low public health risk.

  18. Selective Leaching of Dissolved Organic Matter From Alpine Permafrost Soils on the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Wang, Yinghui; Xu, Yunping; Spencer, Robert G. M.; Zito, Phoebe; Kellerman, Anne; Podgorski, David; Xiao, Wenjie; Wei, Dandan; Rashid, Harunur; Yang, Yuanhe

    2018-03-01

    Ongoing global temperature rise has caused significant thaw and degradation of permafrost soils on the Qinghai-Tibetan Plateau (QTP). Leaching of organic matter from permafrost soils to aquatic systems is highly complex and difficult to reproduce in a laboratory setting. We collected samples from natural seeps of active and permafrost layers in an alpine swamp meadow on the QTP to shed light on the composition of mobilized dissolved organic matter (DOM) by combining optical measurements, ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry, radiocarbon (14C), and solid-state 13C nuclear magnetic resonance spectroscopy. Our results show that even though the active layer soils contain large amounts of proteins and carbohydrates, there is a selective release of aromatic components, whereas in the deep permafrost layer, carbohydrate and protein components are preferentially leached during the thawing process. Given these different chemical characteristics of mobilized DOM, we hypothesize that photomineralization contributes significantly to the loss of DOM that is leached from the seasonally thawed surface layer. However, with continued warming, biodegradation will become more important since biolabile materials such as protein and carbohydrate are preferentially released from deep-layer permafrost soils. This transition in DOM leachate source and associated chemical composition has ramifications for downstream fluvial networks on the QTP particularly in terms of processing of carbon and associated fluxes.

  19. Rumen prokaryotic communities of ruminants under different feeding paradigms on the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Xue, Dan; Chen, Huai; Zhao, Xinquan; Xu, Shixiao; Hu, Linyong; Xu, Tianwei; Jiang, Lin; Zhan, Wei

    2017-06-01

    Yak and Tibetan sheep are the major indigenous ruminants on the Qinghai-Tibetan Plateau in China. The aim of this work was to study the differences in ruminal fermentation parameters and rumen prokaryotic community composition between hosts and feeding paradigms. The 16S rRNA genes targeting bacteria and archaea were sequenced using the MiSeq platform. The results showed that the prokaryotic community structure between yak and Tibetan sheep was significantly different (PTibetan sheep of the two groups (P=0.026). The core prokaryotic populations that existed in the rumen mostly dominated the structure. There was an obvious correlation of the prokaryotic community composition at the phylum and genus levels with the host or the feeding pattern. In addition, Tibetan sheep showed significantly higher yields of volatile fatty acids (VFAs) than yak, as did the NG group compared with the TMR group. In conclusion, both the host and feeding pattern may influence rumen microbial ecology system, with host effects being more important than those of the feeding pattern. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Amphibians Testing Negative for Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans on the Qinghai-Tibetan Plateau, China

    Institute of Scientific and Technical Information of China (English)

    Supen WANG; Wei ZHU; Liqing FAN; Jiaqi LI; Yiming LI

    2017-01-01

    A disease caused by the fungi Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal) is responsible for recent worldwide declines and extinctions of amphibian populations.The Qinghai-Tibetan Plateau (QTP) is aglobal biodiversity hotspot,yet little is known about the prevalence of Bd and Bsal in this region.In this study,we collected 336 non-invasive skin swabs from wild amphibians (including an exotic amphibian species) on the QTP.In addition,to assess the historical prevalence of Bd and Bsal on the QTP,we collected 117 non-invasive skin swabs from museum-archived amphibian samples (from 1964-1982) originating from the QTP.Our results showed all samples to be negative for Bd and Bsal.The government should ban the potentially harmful introduction of non-native amphibian species to the QTP and educate the public about the impacts of releasing exotic amphibians from chytrid-infected areas into native environments of the QTP.

  1. Prevalence, Associated Risk Factors, and Phylogenetic Analysis of Toxocara vitulorum Infection in Yaks on the Qinghai Tibetan Plateau, China.

    Science.gov (United States)

    Li, Kun; Lan, Yanfang; Luo, Houqiang; Zhang, Hui; Liu, Dongyu; Zhang, Lihong; Gui, Rui; Wang, Lei; Shahzad, Muhammad; Sizhu, Suolang; Li, Jiakui; Chamba, Yangzom

    2016-10-01

    Toxocara vitulorum has been rarely reported in yaks at high altitudes and remote areas of Sichuan Province of Tibetan Plateau of China. The current study was designed to investigate the prevalence, associated risk factors, and phylogenetic characteristics of T. vitulorum in yak calves on the Qinghai Tibetan plateau. Fecal samples were collected from 891 yak calves and were examined for the presence of T. vitulorum eggs by the McMaster technique. A multivariable logistic regression model was employed to explore variables potentially associated with exposure to T. vitulorum infection. T. vitulorum specimens were collected from the feces of yaks in Hongyuan of Sichuan Province, China. DNA was extracted from ascaris. After PCR amplification, the sequencing of ND1 gene was carried out and phylogenetic analyses was performed by MEGA 6.0 software. The results showed that 64 (20.1%; 95% CI 15.8-24.9%), 75 (17.2; 13.8-21.1), 29 (40.9; 29.3-53.2), and 5 (7.6; 2.5-16.8) yak calves were detected out to excrete T. vitulorum eggs in yak calve feces in Qinghai, Tibet, Sichuan, and Gansu, respectively. The present study revealed that high infection and mortality by T. vitulorum is wildly spread on the Qinghai Tibetan plateau, China by fecal examination. Geographical origin, ages, and fecal consistencies are the risk factors associated with T. vitulorum prevalence by logistic regression analysis. Molecular detection and phylogenetic analysis of ND1 gene of T. vitulorum indicated that T. vitulorum in the yak calves on the Qinghai Tibetan plateau are homologous to preveiously studies reported.

  2. Convergent, Parallel and Correlated Evolution of Trophic Morphologies in the Subfamily Schizothoracinae from the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Qi, Delin; Chao, Yan; Guo, Songchang; Zhao, Lanying; Li, Taiping; Wei, Fulei; Zhao, Xinquan

    2012-01-01

    Schizothoracine fishes distributed in the water system of the Qinghai-Tibetan plateau (QTP) and adjacent areas are characterized by being highly adaptive to the cold and hypoxic environment of the plateau, as well as by a high degree of diversity in trophic morphology due to resource polymorphisms. Although convergent and parallel evolution are prevalent in the organisms of the QTP, it remains unknown whether similar evolutionary patterns have occurred in the schizothoracine fishes. Here, we constructed for the first time a tentative molecular phylogeny of the schizothoracine fishes based on the complete sequences of the cytochrome b gene. We employed this molecular phylogenetic framework to examine the evolution of trophic morphologies. We used Pagel's maximum likelihood method to estimate the evolutionary associations of trophic morphologies and food resource use. Our results showed that the molecular and published morphological phylogenies of Schizothoracinae are partially incongruent with respect to some intergeneric relationships. The phylogenetic results revealed that four character states of five trophic morphologies and of food resource use evolved at least twice during the diversification of the subfamily. State transitions are the result of evolutionary patterns including either convergence or parallelism or both. Furthermore, our analyses indicate that some characters of trophic morphologies in the Schizothoracinae have undergone correlated evolution, which are somewhat correlated with different food resource uses. Collectively, our results reveal new examples of convergent and parallel evolution in the organisms of the QTP. The adaptation to different trophic niches through the modification of trophic morphologies and feeding behaviour as found in the schizothoracine fishes may account for the formation and maintenance of the high degree of diversity and radiations in fish communities endemic to QTP. PMID:22470515

  3. Climate change and its impacts on vegetation distribution and net primary productivity of the alpine ecosystem in the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Gao, Qingzhu; Guo, Yaqi; Xu, Hongmei; Ganjurjav, Hasbagen; Li, Yue; Wan, Yunfan; Qin, Xiaobo; Ma, Xin; Liu, Shuo

    2016-06-01

    Changes in climate have caused impacts on ecosystems on all continents scale, and climate change is also projected to be a stressor on most ecosystems even at the rate of low- to medium-range warming scenarios. Alpine ecosystem in the Qinghai-Tibetan Plateau is vulnerable to climate change. To quantify the climate change impacts on alpine ecosystems, we simulated the vegetation distribution and net primary production in the Qinghai-Tibetan Plateau for three future periods (2020s, 2050s and 2080s) using climate projection for RCPs (Representative Concentration Pathways) RCP4.5 and RCP8.5 scenarios. The modified Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ model) was parameter and test to make it applicable to the Qinghai-Tibetan Plateau. Climate projections that were applied to LPJ model in the Qinghai-Tibetan Plateau showed trends toward warmer and wetter conditions. Results based on climate projections indicated changes from 1.3°C to 4.2°C in annual temperature and changes from 2% to 5% in annual precipitation. The main impacts on vegetation distribution was increase in the area of forests and shrubs, decrease in alpine meadows which mainly replaced by shrubs which dominated the eastern plateau, and expanding in alpine steppes to the northwest dominated the western and northern plateau. The NPP was projected to increase by 79% and 134% under the RCP4.5 and RCP8.5. The projected NPP generally increased about 200gC·m(-2)·yr(-1) in most parts of the plateau with a gradual increase from the eastern to the western region of the Qinghai-Tibetan Plateau at the end of this century. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Experimental Warming Aggravates Degradation-Induced Topsoil Drought in Alpine Meadows of The Qinghai-Tibetan Plateau

    Science.gov (United States)

    Xue, X.

    2017-12-01

    Climatic warming is presumed to cause topsoil drought by increasing evapotranspiration and water infiltration, and by progressively inducing land degradation in alpine meadows of the Qinghai-Tibetan Plateau. However, how soil moisture and temperature patterns of degraded alpine meadows respond to climate warming remains unclear. A six-year continuous warming experiment was carried out in both degraded and undegraded alpine meadows in the source region of the Yangtze River. The goal was to identify the effects of climatic warming and land degradation on soil moisture (θ), soil surface temperature (Tsfc), and soil temperature (Ts). In the present study, land degradation significantly reduced θ by 4.5-6.1% at a depth of 0-100 cm (P soil surface. Experimental warming aggravated topsoil drought caused by land degradation, intensified the magnitude of degradation, and caused a positive feedback in the degraded alpine meadow ecosystem. Therefore, an immediate need exists to restore degraded alpine meadow grasslands in the Qinghai-Tibetan Plateau in anticipation of a warmer future.

  5. Effect of degradation intensity on grassland ecosystem services in the alpine region of Qinghai-Tibetan Plateau, China.

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    Lu Wen

    Full Text Available The deterioration of alpine grassland has great impact on ecosystem services in the alpine region of Qinghai-Tibetan Plateau. However, the effect of grassland degradation on ecosystem services and the consequence of grassland deterioration on economic loss still remains a mystery. So, in this study, we assessed four types of ecosystem services following the Millennium Ecosystem Assessment classification, along a degradation gradient. Five sites of alpine grassland at different levels of degradation were investigated in Guoluo Prefecture of Qinghai Province, China. The species composition, aboveground biomass, soil total organic carbon (TOC, and soil total nitrogen (TN were tested to evaluate major ecological services of the alpine grassland. We estimated the value of primary production, carbon storage, nitrogen recycling, and plant diversity. The results show the ecosystem services of alpine grassland varied along the degradation gradient. The ecosystem services of degraded grassland (moderate, heavy and severe were all significantly lower than non-degraded grassland. Interestingly, the lightly degraded grassland provided more economic benefit from carbon maintenance and nutrient sequestration compared to non-degraded. Due to the destruction of the alpine grassland, the economic loss associated with decrease of biomass in 2008 was $198/ha. Until 2008, the economic loss caused by carbon emissions and nitrogen loss on severely degraded grassland was up to $8 033/ha and $13 315/ha, respectively. Urgent actions are required to maintain or promote the ecosystem services of alpine grassland in the Qinghai-Tibetan Plateau.

  6. Effect of degradation intensity on grassland ecosystem services in the alpine region of Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Wen, Lu; Dong, Shikui; Li, Yuanyuan; Li, Xiaoyan; Shi, Jianjun; Wang, Yanlong; Liu, Demei; Ma, Yushou

    2013-01-01

    The deterioration of alpine grassland has great impact on ecosystem services in the alpine region of Qinghai-Tibetan Plateau. However, the effect of grassland degradation on ecosystem services and the consequence of grassland deterioration on economic loss still remains a mystery. So, in this study, we assessed four types of ecosystem services following the Millennium Ecosystem Assessment classification, along a degradation gradient. Five sites of alpine grassland at different levels of degradation were investigated in Guoluo Prefecture of Qinghai Province, China. The species composition, aboveground biomass, soil total organic carbon (TOC), and soil total nitrogen (TN) were tested to evaluate major ecological services of the alpine grassland. We estimated the value of primary production, carbon storage, nitrogen recycling, and plant diversity. The results show the ecosystem services of alpine grassland varied along the degradation gradient. The ecosystem services of degraded grassland (moderate, heavy and severe) were all significantly lower than non-degraded grassland. Interestingly, the lightly degraded grassland provided more economic benefit from carbon maintenance and nutrient sequestration compared to non-degraded. Due to the destruction of the alpine grassland, the economic loss associated with decrease of biomass in 2008 was $198/ha. Until 2008, the economic loss caused by carbon emissions and nitrogen loss on severely degraded grassland was up to $8 033/ha and $13 315/ha, respectively. Urgent actions are required to maintain or promote the ecosystem services of alpine grassland in the Qinghai-Tibetan Plateau.

  7. Key sources and seasonal dynamics of greenhouse gas fluxes from yak grazing systems on the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Liu, Yang; Yan, Caiyu; Matthew, Cory; Wood, Brennon; Hou, Fujiang

    2017-01-01

    Greenhouse gas (GHG) emissions from livestock grazing systems are contributing to global warming. To examine the influence of yak grazing systems on GHG fluxes and relationships between GHG fluxes and environmental factors, we measured carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes over three key seasons in 2012 and 2013 from a range of potential sources, including: alpine meadows, dung patches, manure heaps and yak night pens, on the Qinghai-Tibetan Plateau. We also estimated the total annual global warming potential (GWP, CO2-equivalents) from family farm grazing yaks using our measured results and other published data. In this study, GHG fluxes per unit area from night pens and composting manure heaps were higher than from dung patches and alpine meadows. Increased moisture content and surface temperature of soil and manure were major factors increasing CO2 and CH4 fluxes. High contributions of CH4 and N2O (21.1% and 44.8%, respectively) to the annual total GWP budget (334.2 tonnes) strongly suggest these GHG other than CO2 should not be ignored when estimating GWP from the family farm grazing yaks on the Qinghai-Tibetan Plateau for the purposes of determining national and regional land use policies or compiling global GHG inventories.

  8. Role of the Qinghai-Tibetan Plateau uplift in the Northern Hemisphere disjunction: evidence from two herbaceous genera of Rubiaceae.

    Science.gov (United States)

    Deng, Tao; Zhang, Jian-Wen; Meng, Ying; Volis, Sergei; Sun, Hang; Nie, Ze-Long

    2017-10-17

    To assess the role of the Qinghai-Tibetan Plateau uplift in shaping the intercontinental disjunction in Northern Hemisphere, we analyzed the origin and diversification within a geological timeframe for two relict herbaceous genera, Theligonum and Kelloggia (Rubiaceae). Phylogenetic relationships within and between Theligonum and Kelloggia as well as their relatives were inferred using five chloroplast markers with parsimony, Bayesian and maximum-likelihood approaches. Migration routes and evolution of these taxa were reconstructed using Bayesian relaxed molecular clock and ancestral area reconstruction. Our results suggest the monophyly of each Theligonum and Kelloggia. Eastern Asian and North American species of Kelloggia diverged at ca.18.52 Mya and the Mediterranean species of Theligonum diverged from eastern Asian taxa at ca.13.73 Mya. Both Kelloggia and Theligonum are Tethyan flora relicts, and their ancestors might have been occurred in warm tropical to subtropical environments along the Tethys coast. The Qinghai-Tibetan Plateau separated the eastern and western Tethyan area may contribute significantly to the disjunct distributions of Theligonum, and the North Atlantic migration appears to be the most likely pathway of expansion of Kelloggia to North America. Our results highlight the importance role of the QTP uplift together with corresponding geological and climatic events in shaping biodiversity and biogeographic distribution in the Northern Hemisphere.

  9. a Research on Monitoring Surface Deformation and Relationships with Surface Parameters in Qinghai Tibetan Plateau Permafrost

    Science.gov (United States)

    Mi, S. J.; Li, Y. T.; Wang, F.; Li, L.; Ge, Y.; Luo, L.; Zhang, C. L.; Chen, J. B.

    2017-09-01

    The Qinghai Tibetan Plateau permafrost has been the largest permafrost region in middle-low latitude in the world for its high altitude. For the large area permafrost, especially surface deformation brought by it, have serious influence on the road engineering, road maintaining and regional economic development. Consequently, it is essential to monitor the surface deformation and study factors that influent it. We monitored an area named Wudaoliang from July 25, 2015 to June 1, 2016 and 15 Sentinel images were obtained during this time. The area we chose is about 35 kilometers long and 2 kilometers wide, and the national road 109 of China passes through the area. The traditional PS-INSAR (Persistent Scatterer Interferometric Synthetic Aperture Radar) method is not suitable because less historical images in the research area and leading to the number of PS (Persistent Scatterer) points is not enough to obtain accurate deformation results. Therefore, in this paper, we used another method which named QUASI-PSInSAR (QUASI Persistent Scatterer Interferometric Synthetic Aperture Radar) to acquire deformation for it has the advantage to weaken or eliminate the effects of spatial and temporal correlation, which has proved by other scholar. After processing 15 images in the SARproz software, we got the conclusions that, 1) the biggest deformation velocity in the whole area was about 127.9mm/year and about 109.3 mm/year in the road; 2) apparent deformation which have surface deformation more than 30mm/year was about 1.7Km in the road. Meanwhile, soil moisture(SM), Land surface temperature (LST) and surface water(SW), which are primary parameters of the land surface over the same time were reversed by using Sentinel data, Landsat data and ZY-3 data, respectively. After analyzing SM, LST , SW and deformation, we obtained that wet areas which had bigger SM, lower LST and more SW, had greater percentage of severe deformation than arid areas; besides, deformation pattern were

  10. Comparison of methanogen diversity of yak (Bos grunniens) and cattle (Bos taurus) from the Qinghai-Tibetan plateau, China

    Science.gov (United States)

    2012-01-01

    Background Methane emissions by methanogen from livestock ruminants have significantly contributed to the agricultural greenhouse gas effect. It is worthwhile to compare methanogen from “energy-saving” animal (yak) and normal animal (cattle) in order to investigate the link between methanogen structure and low methane production. Results Diversity of methanogens from the yak and cattle rumen was investigated by analysis of 16S rRNA gene sequences from rumen digesta samples from four yaks (209 clones) and four cattle (205 clones) from the Qinghai-Tibetan Plateau area (QTP). Overall, a total of 414 clones (i.e. sequences) were examined and assigned to 95 operational taxonomic units (OTUs) using MOTHUR, based upon a 98% species-level identity criterion. Forty-six OTUs were unique to the yak clone library and 34 OTUs were unique to the cattle clone library, while 15 OTUs were found in both libraries. Of the 95 OTUs, 93 putative new species were identified. Sequences belonging to the Thermoplasmatales-affiliated Linage C (TALC) were found to dominate in both libraries, accounting for 80.9% and 62.9% of the sequences from the yak and cattle clone libraries, respectively. Sequences belonging to the Methanobacteriales represented the second largest clade in both libraries. However, Methanobrevibacter wolinii (QTPC 110) was only found in the cattle library. The number of clones from the order Methanomicrobiales was greater in cattle than in the yak clone library. Although the Shannon index value indicated similar diversity between the two libraries, the Libshuff analysis indicated that the methanogen community structure of the yak was significantly different than those from cattle. Conclusion This study revealed for the first time the molecular diversity of methanogen community in yaks and cattle in Qinghai-Tibetan Plateau area in China. From the analysis, we conclude that yaks have a unique rumen microbial ecosystem that is significantly different from that of cattle

  11. Signals of pollution revealed by trace elements in recent snow from mountain glaciers at the Qinghai-Tibetan plateau.

    Science.gov (United States)

    Li, Yuefang; Li, Zhen; Cozzi, Giulio; Turetta, Clara; Barbante, Carlo; Huang, Ju; Xiong, Longfei

    2018-06-01

    In order to extract pollution signal of trace elements (TEs) in glacier snow at the Qinghai-Tibetan plateau of China by human activities, concentrations of 18 TEs (Al, Ti, Fe, Rb, Sr, Ba, V, Cr, Mn, Li, Cu, Co, Mo, Cs, Sb, Pb, Tl, and U), 14 rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), Y and Th in digested snow samples from five glaciers in April-May 2013 before monsoon season were measured. Results shown that higher TEs concentrations were found in glaciers at the northern plateau while lower concentrations in glaciers at the central and southern plateau. Discussion revealed that EF values calculated from elements with mass fraction TEs such as Sb, Sr, As, Cu and Pb etc. Analysis indicated that most TEs mainly originated from dust sources, whereas Pb, Cu, Mo and Sb showed occasionally significant contributions from polluted sources in three snow pits and the GRHK surface snow samples. The pollution probably originated from mining and smelting, road transport emissions on the plateau and some regions outside of the plateau. Dust provenance tracing results based on REEs indicated that Taklimakan Desert, Qaidam Basin, and Tibetan surface soil were the potential dust sources for the studied glaciers, while the Indian Thar Desert was an occasional dust sources for YZF,XDKMD and GRHK snow samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Shiga toxin-producing Escherichia coli in yaks (Bos grunniens from the Qinghai-Tibetan Plateau, China.

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    Xiangning Bai

    Full Text Available Shiga toxin (Stx-producing Escherichia coli (STEC are recognized as important human pathogens of public health concern. Many animals are the sources of STEC. In this study we determined the occurrence and characteristics of the STEC in yaks (Bos grunniens from the Qinghai-Tibetan plateau, China. A total of 728 yak fecal samples was collected from June to August, 2012 and was screened for the presence of the stx 1 and stx 2 genes by TaqMan real-time PCR after the sample was enriched in modified Tryptone Soya Broth. Of the 138 (18.96% stx 1 and/or stx 2-positive samples, 85 (61.59% were confirmed to have at least 1 STEC isolate present by culture isolation, from which 128 STEC isolates were recovered. All STEC isolates were serotyped, genotyped by pulsed-field gel electrophoresis (PFGE and characterized for the presence of 16 known virulence factors. Fifteen different O serogroups and 36 different O:H serotypes were identified in the 128 STEC isolates with 21 and 4 untypable for the O and H antigens respectively. One stx 1 subtype (stx 1a and 5 stx 2 subtypes (stx 2a, stx 2b, stx 2c, stx 2d and stx 2g were present in these STEC isolates. Apart from lpfA O157/OI-141, lpfA O157/OI-154, lpfA O113, katP and toxB which were all absent, other virulence factors screened (eaeA, iha, efa1, saa, paa, cnf1, cnf2, astA, subA, exhA and espP were variably present in the 128 STEC isolates. PFGE were successful for all except 5 isolates and separated them into 67 different PFGE patterns. For the 18 serotypes with 2 or more isolates, isolates of the same serotypes had the same or closely related PFGE patterns, demonstrating clonality of these serotypes. This study was the first report on occurrence and characteristics of STEC isolated from yaks (Bos grunniens from the Qinghai-Tibetan plateau, China, and extended the genetic diversity and reservoir host range of STEC.

  13. Comparison of methanogen diversity of yak (Bos grunniens and cattle (Bos taurus from the Qinghai-Tibetan plateau, China

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    Huang Xiao

    2012-10-01

    Full Text Available Abstract Background Methane emissions by methanogen from livestock ruminants have significantly contributed to the agricultural greenhouse gas effect. It is worthwhile to compare methanogen from “energy-saving” animal (yak and normal animal (cattle in order to investigate the link between methanogen structure and low methane production. Results Diversity of methanogens from the yak and cattle rumen was investigated by analysis of 16S rRNA gene sequences from rumen digesta samples from four yaks (209 clones and four cattle (205 clones from the Qinghai-Tibetan Plateau area (QTP. Overall, a total of 414 clones (i.e. sequences were examined and assigned to 95 operational taxonomic units (OTUs using MOTHUR, based upon a 98% species-level identity criterion. Forty-six OTUs were unique to the yak clone library and 34 OTUs were unique to the cattle clone library, while 15 OTUs were found in both libraries. Of the 95 OTUs, 93 putative new species were identified. Sequences belonging to the Thermoplasmatales-affiliated Linage C (TALC were found to dominate in both libraries, accounting for 80.9% and 62.9% of the sequences from the yak and cattle clone libraries, respectively. Sequences belonging to the Methanobacteriales represented the second largest clade in both libraries. However, Methanobrevibacter wolinii (QTPC 110 was only found in the cattle library. The number of clones from the order Methanomicrobiales was greater in cattle than in the yak clone library. Although the Shannon index value indicated similar diversity between the two libraries, the Libshuff analysis indicated that the methanogen community structure of the yak was significantly different than those from cattle. Conclusion This study revealed for the first time the molecular diversity of methanogen community in yaks and cattle in Qinghai-Tibetan Plateau area in China. From the analysis, we conclude that yaks have a unique rumen microbial ecosystem that is significantly different

  14. Prevalence of Circulating Antibodies to Bovine Herpesvirus 1 in Yaks (Bos grunniens) on the Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Han, Zhaoqing; Gao, Jianfeng; Li, Kun; Shahzad, Muhammad; Nabi, Fazul; Zhang, Ding; Li, Jiakui; Liu, Zhengfei

    2016-01-01

    Bovine Herpesvirus 1 (BoHV-1) causes infections with many clinical signs, including rhinotracheitis, encephalitis, and genital lesions. The virus occurs worldwide in bovines, and in recent years, it has been reported in yaks (Bos grunniens) inhabiting the Tibetan Plateau in China. However, there is little epidemiologic data describing BoHV-1 infections in China's yak herds. We conducted a cross-sectional study on the Qinghai-Tibetan Plateau (QTP) in China July 2011-July 2012 to estimate the prevalence of BoHV-1 antibody in yak herds. We collected 1,840 serum samples from yaks on the QTP, in Tibet (988 yaks), Qinghai (475 yaks), and Sichuan (377 yaks) Provinces. Using an enzyme-linked immunosorbent assay, we found that 381 (38.6%) of the Tibetan samples, 212 (44.6%) of the Qinghai samples, and 105 (27.9%) of the Sichuan samples had detectable antibodies to BoHV-1. Given that this high prevalence of infection in yaks could result in heavy economic losses, we suggest that an effective management program, including vaccination and strategies for infection control, be developed.

  15. Alfa analysis of genetic diversity in populus cathayana rehd originating from south eastern Qinghai-Tibetan plateau of China

    International Nuclear Information System (INIS)

    Chen, K.; Peng, Y.

    2010-01-01

    The wide geographical and climatic distribution of Populus cathayana Rehd indicates that there is a large amount of genetic diversity available, which can be exploited for conservation, breeding programs and afforestation schemes. In our study, genetic diversity was evaluated in the natural populations of P. cathayana originating from southern and eastern areas of the Qinghai-Tibetan Plateau of China by means of AFLP markers. For four primer combinations, a total of 175 bands were obtained of which 173 (98.9%) were polymorphic. Six natural populations of P. cathayana possessed different levels of genetic diversity, high level of genetic differentiation existed among the populations (G/sub st) =0.489) of P. cathayana. Individuals cluster and PCO analysis based on Jaccards's similarity coefficient also showed evident population genetic structure with high level of population genetic differentiation. The long evolutionary process coupled with genetic drift within populations, rather than contemporary gene flow, are the major forces shaping genetic structure of P. cathayana populations. Moreover, there was no correspondence between geographical and genetic distances in the populations of P. cathayana, seldom gene exchange among the populations and different selection pressures may be the causes. Our findings of different levels of genetic diversity within populations and high level of genetic differentiation among the populations provided promising condition for further breeding and conservation programs. (author)

  16. Change in frozen soils and its effect on regional hydrology, upper Heihe basin, northeastern Qinghai-Tibetan Plateau

    Science.gov (United States)

    Gao, Bing; Yang, Dawen; Qin, Yue; Wang, Yuhan; Li, Hongyi; Zhang, Yanlin; Zhang, Tingjun

    2018-02-01

    Frozen ground has an important role in regional hydrological cycles and ecosystems, particularly on the Qinghai-Tibetan Plateau (QTP), which is characterized by high elevations and a dry climate. This study modified a distributed, physically based hydrological model and applied it to simulate long-term (1971-2013) changes in frozen ground its the effects on hydrology in the upper Heihe basin, northeastern QTP. The model was validated against data obtained from multiple ground-based observations. Based on model simulations, we analyzed spatio-temporal changes in frozen soils and their effects on hydrology. Our results show that the area with permafrost shrank by 8.8 % (approximately 500 km2), predominantly in areas with elevations between 3500 and 3900 m. The maximum depth of seasonally frozen ground decreased at a rate of approximately 0.032 m decade-1, and the active layer thickness over the permafrost increased by approximately 0.043 m decade-1. Runoff increased significantly during the cold season (November-March) due to an increase in liquid soil moisture caused by rising soil temperatures. Areas in which permafrost changed into seasonally frozen ground at high elevations showed especially large increases in runoff. Annual runoff increased due to increased precipitation, the base flow increased due to changes in frozen soils, and the actual evapotranspiration increased significantly due to increased precipitation and soil warming. The groundwater storage showed an increasing trend, indicating that a reduction in permafrost extent enhanced the groundwater recharge.

  17. Phylogeography and allopatric divergence of cypress species (Cupressus L.) in the Qinghai-Tibetan Plateau and adjacent regions.

    Science.gov (United States)

    Xu, Tingting; Abbott, Richard J; Milne, Richard I; Mao, Kangshan; Du, Fang K; Wu, Guili; Ciren, Zhaxi; Miehe, Georg; Liu, Jianquan

    2010-06-22

    Although allopatric speciation is viewed as the most common way in which species originate, allopatric divergence among a group of closely related species has rarely been examined at the population level through phylogeographic analysis. Here we report such a case study on eight putative cypress (Cupressus) species, which each have a mainly allopatric distribution in the Qinghai-Tibetan Plateau (QTP) and adjacent regions. The analysis involved sequencing three plastid DNA fragments (trnD-trnT, trnS-trnG and trnL-trnF) in 371 individuals sampled from populations at 66 localities. Both phylogenetic and network analyses showed that most DNA haplotypes recovered or haplotype-clustered lineages resolved were largely species-specific. Across all species, significant phylogeographic structure (N(ST) > G(ST), P allopatric divergence in Cupressus by restricting gene flow and fixing local, species-specific haplotypes in geographically isolated populations. The low levels of intraspecific diversity present in most species might stem from population bottlenecks brought about by recurrent periods of unfavorable climate and more recently by the negative impacts of human activities on species' distributions. Our findings shed new light on the importance of geographical isolation caused by the uplift of the QTP on the development of high plant species diversity in the QTP biodiversity hotspot.

  18. Diversity and Distribution of Archaea Community along a Stratigraphic Permafrost Profile from Qinghai-Tibetan Plateau, China

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    Shiping Wei

    2014-01-01

    Full Text Available Accompanying the thawing permafrost expected to result from the climate change, microbial decomposition of the massive amounts of frozen organic carbon stored in permafrost is a potential emission source of greenhouse gases, possibly leading to positive feedbacks to the greenhouse effect. In this study, the community composition of archaea in stratigraphic soils from an alpine permafrost of Qinghai-Tibetan Plateau was investigated. Phylogenic analysis of 16S rRNA sequences revealed that the community was predominantly constituted by Crenarchaeota and Euryarchaeota. The active layer contained a proportion of Crenarchaeota at 51.2%, with the proportion of Euryarchaeota at 48.8%, whereas the permafrost contained 41.2% Crenarchaeota and 58.8% Euryarchaeota, based on 16S rRNA gene sequence analysis. OTU1 and OTU11, affiliated to Group 1.3b/MCG-A within Crenarchaeota and the unclassified group within Euryarchaeota, respectively, were widely distributed in all sediment layers. However, OTU5 affiliated to Group 1.3b/MCG-A was primarily distributed in the active layers. Sequence analysis of the DGGE bands from the 16S rRNAs of methanogenic archaea showed that the majority of methanogens belonged to Methanosarcinales and Methanomicrobiales affiliated to Euryarchaeota and the uncultured ZC-I cluster affiliated to Methanosarcinales distributed in all the depths along the permafrost profile, which indicated a dominant group of methanogens occurring in the cold ecosystems.

  19. Gene Flow Results in High Genetic Similarity Between Sibiraea (Rosaceae species in the Qinghai-Tibetan Plateau

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    Peng-Cheng Fu

    2016-10-01

    Full Text Available Studying closely related species and divergent populations provides insight into the process of speciation. Previous studies showed that the Sibiraea complex's evolutionary history on the Qinghai-Tibetan Plateau (QTP was confusing and could not be distinguishable on the molecular level. In this study, the genetic structure and gene flow of S. laevigata and S. angustata on the QTP was examined across 45 populations using 8 microsatellite loci. Microsatellites revealed high genetic diversity in Sibiraea populations. Most of the variance was detected within populations (87.45% rather than between species (4.39%. We found no significant correlations between genetic and geographical distances among populations. Bayesian cluster analysis grouped all individuals in the sympatric area of Sibiraea into one cluster and other individuals of S. angustata into another. Divergence history analysis based on the approximate Bayesian computation method indicated that the populations of S. angustata at the sympatric area derived from the admixture of 2 species. The assignment test assigned all individuals to populations of their own species rather than its congeneric species. Consistently, intraspecies were detected rather than interspecies first-generation migrants. The bidirectional gene flow in long-term patterns between the 2 species was asymmetric, with more from S. angustata to S. laevigata. In conclusion, the Sibiraea complex was distinguishable on the molecular level using microsatellite loci. We found that the high genetic similarity of these 2 species resulted from huge bidirectional gene flow, especially on the sympatric area where population admixtures between the species occurred.

  20. Response of greenhouse gas emissions from three types of wetland soils to simulated temperature change on the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Liu, Yi; Liu, Guihua; Xiong, Ziqian; Liu, Wenzhi

    2017-12-01

    Wetlands emit a large quantity of greenhouse gases into the atmosphere and contribute significantly to global warming. The Qinghai-Tibetan Plateau, known as the ;Third Pole; of the earth, contains abundant and diverse wetlands. Due to increasing human-induced pressures such as reclamation, overgrazing and climate change, many plateau wetlands have been degraded or destroyed. Until now, the response of soil greenhouse gas emissions to extreme summer temperatures in the plateau wetlands remains unknown. In this study, we collected 36 soil samples from riverine, lacustrine and palustrine wetlands on the Qinghai-Tibetan Plateau. We compared the carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions from soils incubated aerobically at 7, 12, and 19 °C. The results showed that the emissions of CH4 and N2O but not CO2 were significantly affected by the simulated temperature change. The N2O emission rate was considerably higher in palustrine wetlands compared with lacustrine and riverine wetlands. However, the CO2 and CH4 emissions did not differ significantly among the three wetland types. The ratio of CO2 to CH4 production increased with increasing incubation temperatures. The global warming potential of greenhouse gases at 19 °C was approximately 1.18 and 2.12 times greater than that at 12 and 7 °C, respectively. Our findings suggest that temperature change has a strong effect on soil greenhouse gas emissions and global warming potential of wetlands on the Qinghai-Tibetan Plateau, especially palustrine wetlands. Therefore, targeted strategies should be developed to mitigate the potential impacts of climate warming on the plateau.

  1. Spiroides shrubs on Qinghai-Tibetan Plateau: Multilocus phylogeography and palaeodistributional reconstruction of Spiraea alpina and S. Mongolica (Rosaceae).

    Science.gov (United States)

    Khan, Gulzar; Zhang, Faqi; Gao, Qingbo; Fu, Pengcheng; Zhang, Yu; Chen, Shilong

    2018-06-01

    A common hypothesis for the rich biodiversity found in mountains is uplift-driven diversification. Using a multilocus approach, here we assessed the influence of Qinghai-Tibetan Plateau (QTP) uplift and fluctuating regional climate on genetic diversity of two sister spiroides shrubs, Spiraea alpina and S. mongolica. Combined with palaeodistributional reconstruction modelling, we investigated the current and past-predicted distribution of these species under different climatic episodes. The study demonstrated that continuous pulses of retreat and expansion during last glacial-interglacial episodes, combined with the uplifting of QTP shaped the current distribution of these species. All the populations showed high level of genetic diversity based on both cpDNA and SSR markers. The average gene diversity within populations based on cpDNA markers was 0.383 ± 0.052 for S. alpina and 0.477 ± 0.048 for S. mongolica. The observed and expected heterozygosities based on SSR for both Spiraea alpina and S. mongolicawere H E (0.72-0.90)/H O (0.35-0.78) and H E (0.77-0.92)/H O (0.47-0.77) respectively. Palaeodistributional reconstruction indicated species' preferences at southeastern edge of the plateau during last glacial maximum, at higher altitude areas of QTP and range expansion to central plateau during the interglacial episodes. Assignment tests in STRUCTURE, discriminant analysis of principal coordinates and Immigrants analysis in GENECLASS based on nuclear SSR markers did not support the hypothesis of gene flow between both the species. However, maximum likelihood approach based on cpDNA showed sharing of haplotypes between both species. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Great genetic differentiation among populations of Meconopsis integrifolia and its implication for plant speciation in the Qinghai-Tibetan Plateau.

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    Fu-Sheng Yang

    Full Text Available The complex tectonic events and climatic oscillations in the Qinghai-Tibetan Plateau (QTP, the largest and highest plateau in the world, are thought to have had great effects on the evolutionary history of the native plants. Of great interest is to investigate plant population genetic divergence in the QTP and its correlation with the geologic and climatic changes. We conducted a range-wide phylogeographical analysis of M. integrifolia based on the chloroplast DNA (cpDNA trnL-trnF and trnfM-trnS regions, and defined 26 haplotypes that were phylogenetically divided into six clades dated to the late Tertiary. The six clades correspond, respectively, to highly differentiated population groups that do not overlap in geographic distribution, implying that the mountain ranges acting as corridors or barriers greatly affected the evolutionary history of the QTP plants. The older clade of M. integrifolia only occurs in the southwest of the species' range, whereas the distributions of younger clades extend northeastward in the eastern QTP, suggesting that climatic divergence resulting from the uplift of the QTP triggered the initial divergence of M. integrifolia native to the plateau. Also, the nrDNA ITS region was used to clarify the unexpected phylogenetic relationships of cpDNA haplotypes between M. integrifolia and M. betonicifolia. The topological incongruence between the two phylogenies suggests an ancestral hybridization between the two species. Our study indicates that geographic isolation and hybridization are two important mechanisms responsible for the population differentiation and speciation of Meconopsis, a species-rich genus with complex polyploids.

  3. Microbial diversity in hummock and hollow soils of three wetlands on the Qinghai-Tibetan Plateau revealed by 16S rRNA pyrosequencing.

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    Yongcui Deng

    Full Text Available The wetlands of the Qinghai-Tibetan Plateau are believed to play an important role in global nutrient cycling, but the composition and diversity of microorganisms in this ecosystem are poorly characterized. An understanding of the effects of geography and microtopography on microbial populations will provide clues to the underlying mechanisms that structure microbial communities. In this study, we used pyrosequencing-based analysis of 16S rRNA gene sequences to assess and compare the composition of soil microbial communities present in hummock and hollow soils from three wetlands (Dangxiong, Hongyuan and Maduo on the Qinghai-Tibetan Plateau, the world's highest plateau. A total of 36 bacterial phyla were detected. Proteobacteria (34.5% average relative abundance, Actinobacteria (17.3% and Bacteroidetes (11% had the highest relative abundances across all sites. Chloroflexi, Acidobacteria, Verrucomicrobia, Firmicutes, and Planctomycetes were also relatively abundant (1-10%. In addition, archaeal sequences belonging to Euryarchaea, Crenarchaea and Thaumarchaea were detected. Alphaproteobacteria sequences, especially of the order Rhodospirillales, were significantly more abundant in Maduo than Hongyuan and Dangxiong wetlands. Compared with Hongyuan soils, Dangxiong and Maduo had significantly higher relative abundances of Gammaproteobacteria sequences (mainly order Xanthomonadales. Hongyuan wetland had a relatively high abundance of methanogens (mainly genera Methanobacterium, Methanosarcina and Methanosaeta and methanotrophs (mainly Methylocystis compared with the other two wetlands. Principal coordinate analysis (PCoA indicated that the microbial community structure differed between locations and microtopographies and canonical correspondence analysis indicated an association between microbial community structure and soil properties or geography. These insights into the microbial community structure and the main controlling factors in wetlands of

  4. Microbial diversity in hummock and hollow soils of three wetlands on the Qinghai-Tibetan Plateau revealed by 16S rRNA pyrosequencing.

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    Deng, Yongcui; Cui, Xiaoyong; Hernández, Marcela; Dumont, Marc G

    2014-01-01

    The wetlands of the Qinghai-Tibetan Plateau are believed to play an important role in global nutrient cycling, but the composition and diversity of microorganisms in this ecosystem are poorly characterized. An understanding of the effects of geography and microtopography on microbial populations will provide clues to the underlying mechanisms that structure microbial communities. In this study, we used pyrosequencing-based analysis of 16S rRNA gene sequences to assess and compare the composition of soil microbial communities present in hummock and hollow soils from three wetlands (Dangxiong, Hongyuan and Maduo) on the Qinghai-Tibetan Plateau, the world's highest plateau. A total of 36 bacterial phyla were detected. Proteobacteria (34.5% average relative abundance), Actinobacteria (17.3%) and Bacteroidetes (11%) had the highest relative abundances across all sites. Chloroflexi, Acidobacteria, Verrucomicrobia, Firmicutes, and Planctomycetes were also relatively abundant (1-10%). In addition, archaeal sequences belonging to Euryarchaea, Crenarchaea and Thaumarchaea were detected. Alphaproteobacteria sequences, especially of the order Rhodospirillales, were significantly more abundant in Maduo than Hongyuan and Dangxiong wetlands. Compared with Hongyuan soils, Dangxiong and Maduo had significantly higher relative abundances of Gammaproteobacteria sequences (mainly order Xanthomonadales). Hongyuan wetland had a relatively high abundance of methanogens (mainly genera Methanobacterium, Methanosarcina and Methanosaeta) and methanotrophs (mainly Methylocystis) compared with the other two wetlands. Principal coordinate analysis (PCoA) indicated that the microbial community structure differed between locations and microtopographies and canonical correspondence analysis indicated an association between microbial community structure and soil properties or geography. These insights into the microbial community structure and the main controlling factors in wetlands of the Qinghai-Tibetan

  5. Phylogeography and allopatric divergence of cypress species (Cupressus L. in the Qinghai-Tibetan Plateau and adjacent regions

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    Ciren Zhaxi

    2010-06-01

    Full Text Available Abstract Background Although allopatric speciation is viewed as the most common way in which species originate, allopatric divergence among a group of closely related species has rarely been examined at the population level through phylogeographic analysis. Here we report such a case study on eight putative cypress (Cupressus species, which each have a mainly allopatric distribution in the Qinghai-Tibetan Plateau (QTP and adjacent regions. The analysis involved sequencing three plastid DNA fragments (trnD-trnT, trnS-trnG and trnL-trnF in 371 individuals sampled from populations at 66 localities. Results Both phylogenetic and network analyses showed that most DNA haplotypes recovered or haplotype-clustered lineages resolved were largely species-specific. Across all species, significant phylogeographic structure (NST >GST, P C. duclouxiana and C. chengiana, which are distributed in the eastern QTP region, contained more haplotypes and higher diversity than five species with restricted distributions in the western highlands of the QTP. The remaining species, C. funebris, is widely cultivated and contained very little cpDNA diversity. Conclusions It is concluded that the formation of high mountain barriers separating deep valleys in the QTP and adjacent regions caused by various uplifts of the plateau since the early Miocene most likely promoted allopatric divergence in Cupressus by restricting gene flow and fixing local, species-specific haplotypes in geographically isolated populations. The low levels of intraspecific diversity present in most species might stem from population bottlenecks brought about by recurrent periods of unfavorable climate and more recently by the negative impacts of human activities on species' distributions. Our findings shed new light on the importance of geographical isolation caused by the uplift of the QTP on the development of high plant species diversity in the QTP biodiversity hotspot.

  6. Cuticular waxes in alpine meadow plants: climate effect inferred from latitude gradient in Qinghai-Tibetan Plateau.

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    Guo, Yanjun; Guo, Na; He, Yuji; Gao, Jianhua

    2015-09-01

    Alpine meadow ecosystems are susceptible to climate changes. Still, climate impact on cuticular wax in alpine meadow plants is poorly understood. Assessing the variations of cuticular wax in alpine meadow plants across different latitudes might be useful for predicting how they may respond to climate change. We studied nine alpine meadows in a climate gradient in the east side of Qinghai-Tibetan Plateau, with mean annual temperature ranging from -7.7 to 3.2°C. In total, 42 plant species were analyzed for cuticular wax, averaged 16 plant species in each meadow. Only four plant species could be observed in all sampling meadows, including Kobresia humilis,Potentilla nivea,Anaphalis lacteal, and Leontopodium nanum. The amounts of wax compositions and total cuticular wax in the four plant species varied among sampling meadows, but no significant correlation could be observed between them and temperature, precipitation, and aridity index based on plant species level. To analyze the variations of cuticular wax on community level, we averaged the amounts of n-alkanes, aliphatic acids, primary alcohols, and total cuticular wax across all investigated plant species in each sampling site. The mean annual temperature, mean temperature in July, and aridity index were significantly correlated with the averaged amounts of wax compositions and total cuticular wax. The average chain length of n-alkanes in both plant and soil linearly increased with increased temperature, whereas reduced with increased aridity index. No significant correlation could be observed between mean annual precipitation and mean precipitation from June to August and the cuticular wax amounts and average chain length. Our results suggest that the survival of some alpine plants in specific environments might be depended on their abilities in adjusting wax deposition on plant leaves, and the alpine meadow plants as a whole respond to climate change, benefiting the stability of alpine meadow ecosystem.

  7. Isolation and characterization of a new enterovirus F in yak feces in the Qinghai-Tibetan Plateau.

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    He, Huan; Tang, Cheng; Chen, Xinnuo; Yue, Hua; Ren, Yupeng; Liu, Yan; Zhang, Bin

    2017-02-01

    An enterovirus (EV) strain, designated as SWUN-AB001, was isolated in the Qinghai-Tibetan Plateau from a yak with severe diarrheal disease. The complete genome of strain SWUN-AB001 was 7,382 bp in length and shared 35.1-68.5% nt identities with bovine EVs belonging to a candidate new type EV-F7. Using the sequence difference values in the VP1 gene as a criterion for demarcating a new serotype/genotype in the Enterovirus genus, strain SWUN-AB001 had only a 71.1% nt and a 79.2% aa identity, in the VP1 region, with the most closely matched EV, further indicating that a new type of EV had been identified. Phylogenetic analysis of the nt sequence of the viral polyprotein and of VP1 genes demonstrated that the virus fell within the EV-F cluster, but was located in a unique lineage. Furthermore, a large-scale surveillance study indicated that the prevalence of this EV in yaks was 31.05% (95% CI = 25.5-37.6%) in 235 animals with diarrhea and 24.13% (95% CI = 17.4-32.4%) in 116 healthy yaks. However, there was no significant difference in virus prevalence between diarrheal and healthy samples. Interestingly, in the Tibet region, diarrheal feces had a higher incidence of EVs than feces of healthy yaks (odd ratios = 6.03, 95% CI = 1.93-18.86), indicating that the incidence of EV was potentially correlated with the clinical symptom of diarrhea in yaks.

  8. The role of the uplift of the Qinghai-Tibetan Plateau for the evolution of Tibetan biotas.

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    Favre, Adrien; Päckert, Martin; Pauls, Steffen U; Jähnig, Sonja C; Uhl, Dieter; Michalak, Ingo; Muellner-Riehl, Alexandra N

    2015-02-01

    Biodiversity is unevenly distributed on Earth and hotspots of biodiversity are often associated with areas that have undergone orogenic activity during recent geological history (i.e. tens of millions of years). Understanding the underlying processes that have driven the accumulation of species in some areas and not in others may help guide prioritization in conservation and may facilitate forecasts on ecosystem services under future climate conditions. Consequently, the study of the origin and evolution of biodiversity in mountain systems has motivated growing scientific interest. Despite an increasing number of studies, the origin and evolution of diversity hotspots associated with the Qinghai-Tibetan Plateau (QTP) remains poorly understood. We review literature related to the diversification of organisms linked to the uplift of the QTP. To promote hypothesis-based research, we provide a geological and palaeoclimatic scenario for the region of the QTP and argue that further studies would benefit from providing a complete set of complementary analyses (molecular dating, biogeographic, and diversification rates analyses) to test for a link between organismic diversification and past geological and climatic changes in this region. In general, we found that the contribution of biological interchange between the QTP and other hotspots of biodiversity has not been sufficiently studied to date. Finally, we suggest that the biological consequences of the uplift of the QTP would be best understood using a meta-analysis approach, encompassing studies on a variety of organisms (plants and animals) from diverse habitats (forests, meadows, rivers), and thermal belts (montane, subalpine, alpine, nival). Since the species diversity in the QTP region is better documented for some organismic groups than for others, we suggest that baseline taxonomic work should be promoted. © 2014 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge

  9. Variation and control of soil organic carbon and other nutrients in permafrost regions on central Qinghai-Tibetan Plateau

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    Liu, Wenjie; Chen, Shengyun; Zhao, Qian; Ren, Jiawen; Qin, Dahe; Sun, Zhizhong

    2014-01-01

    The variation and control of soil organic carbon (SOC) and other nutrients in permafrost regions are critical for studying the carbon cycle and its potential feedbacks to climate change; however, they are poorly understood. Soil nutrients samples at depths of 0–10, 10–20, 20–30, and 30–40 cm, were sampled eight times in 2009 in alpine swamp meadow, alpine meadow and alpine steppe in permafrost regions of the central Qinghai-Tibetan Plateau. SOC and total nitrogen (TN) in the alpine swamp meadow and meadow decreased with soil depth, whereas the highest SOC content in the alpine steppe was found at depths of 20–30 cm. The vertical profiles of total and available phosphorus (P) and potassium (K) were relatively uniform for all the three grassland types. Correlation and linear regression analyses showed that soil moisture (SM) was the most important parameter for the vertical variation of SOC and other soil nutrients, and that belowground biomass (BGB) was the main source of SOC and TN. The spatial variations (including seasonal variation) of SOC and TN at plot scale were large. The relative deviation of SOC ranged from 7.18 to 41.50 in the alpine swamp meadow, from 2.88 to 35.91 in the alpine meadow, and from 9.33 to 68.38 in the alpine steppe. The spatial variations in the other soil nutrients varied among different grassland types. The most important factors for spatial variations (including seasonal variation) of SOC, TN, total P, available P, and both total and available K were: SM, SM and temperature, SM, air temperature, and SM and BGB, respectively. The large variation in the three grassland types implies that spatial variation at plot scale should be considered when estimating SOC storage and its dynamics. (letter)

  10. Plant recolonization in the Himalaya from the southeastern Qinghai-Tibetan Plateau: Geographical isolation contributed to high population differentiation.

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    Cun, Yu-Zhi; Wang, Xiao-Quan

    2010-09-01

    The Himalaya-Hengduan Mountains region (HHM) in the southern and southeastern Qinghai-Tibetan Plateau (QTP) is considered an important reservoir and a differentiation center for temperate and alpine plants in the Cenozoic. To reveal how plants responded to the Quaternary climatic oscillations in the QTP, the phylogeographical histories of a few subalpine and alpine plants have been investigated, but nearly all studies used only uniparentally inherited cytoplasmic DNA markers, and only a couple of them included sampling from the Himalaya. In this study, range-wide genetic variation of the Himalayan hemlock (Tsuga dumosa), an important forest species in the HHM, was surveyed using DNA markers from three genomes. All markers revealed genetic depauperation in the Himalaya and richness in the Hengduan Mountains populations. Surprisingly, population differentiation of this wind-pollinated conifer is very high in all three genomes, with few common and many private nuclear gene alleles. These results, together with fossil evidence, clearly indicate that T. dumosa recolonized the Himalaya from the Hengduan Mountains before the Last Glacial Maximum (LGM), accompanied with strong founder effects, and the influence of the earlier glaciations on demographic histories of the QTP plants could be much stronger than that of the LGM. The strong population differentiation in T. dumosa could be attributed to restricted gene flow caused by the complicated topography in the HHM that formed during the uplift of the QTP, and thus sheds lights on the importance of geographical isolation in the development of high plant species diversity in this biodiversity hotspot. Copyright 2010 Elsevier Inc. All rights reserved.

  11. Relationship between chemical composition of native forage and nutrient digestibility by Tibetan sheep on the Qinghai-Tibetan Plateau.

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    Yang, Chuntao; Gao, Peng; Hou, Fujiang; Yan, Tianhai; Chang, Shenghua; Chen, Xianjiang; Wang, Zhaofeng

    2018-04-02

    To better utilize native pasture at the high altitude region, three-consecutive-year feeding experiments and a total of seven metabolism trials were conducted to evaluate the impact of three forage stages of maturity on the chemical composition, nutrient digestibility, and energy metabolism of native forage in Tibetan sheep on the Qinghai-Tibetan Plateau (QTP). Forages were harvested from June to July, August to October, and November to December of 2011 to 2013, corresponding to the vegetative, bloom, and senescent stages of the annual forages. Twenty male Tibetan sheep were selected for each study and fed native forage ad libitum. The digestibility of DM, OM, CP, NDF, ADF, DE, DE/GE, and ME/GE were greatest (P digestibility and energy parameters correlated positively (linear, 0.422 to 0.778; quadratic, 0.568 to 0.815; P digestibility. Contrary to previous studies, in this study, ADF content had a greater linear relationship (0.766 vs. 0.563 to 0.732) with OM digestibility than the other parameters of nutrient digestibility. The quadratic relationship between forage CP content and CP digestibility indicates that when forage CP content exceeds the peak point (9.7% DM in the present study), increasing forage CP content could decrease CP digestibility when Tibetan sheep were offered native forage alone on the QTP. Additionally, using the forage CP, EE, NDF, and ADF content to predict DMI (g/kg BW·d) yielded the best fit equation for Tibetan sheep living in the northeast portion of the QTP.

  12. Seasonal variations in carbon dioxide exchange in an alpine wetland meadow on the Qinghai-Tibetan Plateau

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    L. Zhao

    2010-04-01

    Full Text Available Alpine wetland meadow could functions as a carbon sink due to it high soil organic content and low decomposition. However, the magnitude and dynamics of carbon stock in alpine wetland ecosystems are not well quantified. Therefore, understanding how environmental variables affect the processes that regulate carbon fluxes in alpine wetland meadow on the Qinghai-Tibetan Plateau is critical. To address this issue, Gross Primary Production (GPP, Ecosystem Respiration (Reco, and Net Ecosystem Exchange (NEE were examined in an alpine wetland meadow using the eddy covariance method from October 2003 to December 2006 at the Haibei Research Station of the Chinese Academy of Sciences. Seasonal patterns of GPP and Reco were closely associated with leaf area index (LAI. The Reco showed a positive exponential to soil temperature and relatively low Reco occurred during the non-growing season after a rain event. This result is inconsistent with the result observed in alpine shrubland meadow. In total, annual GPP were estimated at 575.7, 682.9, and 630.97 g C m−2 in 2004, 2005, and 2006, respectively. Meanwhile, the Reco were equal to 676.8, 726.4, 808.2 g C m−2, and thus the NEE were 101.1, 44.0 and 173.2 g C m−2. These results indicated that the alpine wetland meadow was a moderately source of carbon dioxide (CO2. The observed carbon dioxide fluxes in the alpine wetland meadow were higher than other alpine meadow such as Kobresia humilis meadow and shrubland meadow.

  13. An EPAS1 haplotype is associated with high altitude polycythemia in male Han Chinese at the Qinghai-Tibetan plateau.

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    Chen, Yu; Jiang, Chunhua; Luo, Yongjun; Liu, Fuyu; Gao, Yuqi

    2014-12-01

    Hemoglobin concentration at high altitude is considered an important marker of high altitude adaptation, and native Tibetans in the Qinghai-Tibetan plateau show lower hemoglobin concentrations than Han people who have emigrated from plains areas. Genetic studies revealed that EPAS1 plays a key role in high altitude adaptation and is associated with the low hemoglobin concentration in Tibetans. Three single nucleotide polymorphisms (rs13419896, rs4953354, rs1868092) of noncoding regions in EPAS1 exhibited significantly different allele frequencies in the Tibetan and Han populations and were associated with low hemoglobin concentrations in Tibetans. To explore the hereditary basis of high altitude polycythemia (HAPC) and investigate the association between EPAS1 and HAPC in the Han population, these 3 single nucleotide polymorphisms were assessed in 318 male Han Chinese HAPC patients and 316 control subjects. Genotyping was performed by high resolution melting curve analysis. The G-G-G haplotype of rs13419896, rs4953354, and rs1868092 was significantly more frequent in HAPC patients than in control subjects, whereas no differences in the allele or genotype frequencies of the 3 single nucleotide polymorphisms were found between HAPC patients and control subjects. Moreover, genotypes of rs1868092 (AA) and rs4953354 (GG) that were not observed in the Chinese Han in the Beijing population were found at frequencies of 1.6% and 0.9%, respectively, in our study population of HAPC patients and control subjects. Carriers of this EPAS1 haplotype (G-G-G, rs13419896, rs4953354, and rs1868092) may have a higher risk for HAPC. These results may contribute to a better understanding of the pathogenesis of HAPC in the Han population. Copyright © 2014 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  14. Using multi-source satellite data to assess snow-cover change in Qinghai-Tibetan Plateau in last decade

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    Jiang, Y.; Chen, F.; Gao, Y.; Barlage, M. J.

    2017-12-01

    Snow cover in Qinghai-Tibetan Plateau (QTP) is a critical component of water cycle and affects regional climate of East Asia. Satellite data from three different sources (i.e., FY3A/B/C, MODIS and IMS) were used to analyze the QTP fractional-snow-cover (FSC) change and associated uncertainties in the last decade. To reduce the high percentage of cloud in FY3A/B/C and MODIS, a four-step cloud removal procedure was applied and effectively reduced the cloud percentage from 40.8-56.1% to 2.2­-­3.3%. The averaged error introduced by the cloud removal procedure was about 2% estimated by a random sampling method. Results show that the snow cover in QTP significantly decreased in recent 5 years. Three data sets (FY3B, MODIS and IMS) showed significant decreased annual FSC at all elevation bands from 2012-2016, and a significant shorter snow season with delayed snow onset and earlier melting. Both IMS and MODIS had a slightly decline annual FSC from 2000 to 3000 m, while MODIS FSC slightly decreased in 2002-2016 and IMS FSC slightly increased from 2006-2016 in the region with elevation higher than 3000 m. Results also show significant uncertainties among the five data sets (FY3A/B/C, MODIS, IMS), although they showed similar fluctuations of daily FSC. IMS had largest snow-cover extent and highest daily FSC due to its multi data sources. FY3A/C and MODIS (observed in the morning) had around 5% higher mean FSC than FY3B (observed in the afternoon) due to the 3 hours detection time gap. The relative error of daily FSC (taking MODIS as `truth') between FY3A/B/C, IMS and MODIS is 23%, -35%, 8% and 63%, respectively, averaged in five elevation bands in 2015-2017.

  15. Socio-economic burden of parasitic infections in yaks from 1984 to 2017 on Qinghai Tibetan Plateau of China-A review.

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    Li, Kun; Shahzad, Muhammad; Zhang, Hui; Jiang, Xiong; Mehmood, Khalid; Zhao, Xiaodong; Li, Jiakui

    2018-04-05

    Yak is an important animal for the Tibetans at Qinghai-Tibetan Plateau of China. The burden of parasitic diseases has been a major threat to the health of yaks at this region presenting a considerable socio-economic losses and impact to yak production and local nomads. Keeping in view, we collected the published papers from 1984 to 2017 on major parasitic infections in yaks by electronic literature search from five databases including CNKI, Google, PubMed, Science Direct and Web of Science. The prevalence of Eimeria, Babesia, Theileria, Hypodermosis, Cystic echinococcosis, Alveolar echinococcosis, Toxoplasma gondii, Neospora caninum, Cryptosporidium, Giardia duodenalis, Enterocytozoon bieneusi, Toxocara vitulorum, and Fascioliasis infection in yaks was found to be 48.02%, 13.06%, 36.11%, 59.85%, 16.93%, 0.99%, 20.50%, 5.14%, 10.00%, 3.68%, 4.07%, 22.23% and 28.7% respectively. Data presented are contemplated to enhance our current understanding on the major parasitic diseases of yaks at Qinghai Tibetan plateau, China. The main aim of this effort is to ameliorate the effects of the parasitic burden in this specie; so that, the attempts are made to minimize the incidence of these infections in future to raise the socio-economic levels of local community. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Field Measurement and Evaluation of the Passive and Active Solar Heating Systems for Residential Building Based on the Qinghai-Tibetan Plateau Case

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    Zhijian Liu

    2017-10-01

    Full Text Available Passive and active solar heating systems have drawn much attention and are widely used in residence buildings in the Qinghai-Tibetan plateau due to its high radiation intensity. In fact, there is still lack of quantitative evaluation of the passive and active heating effect, especially for residential building in the Qinghai-Tibetan plateau areas. In this study, three kinds of heating strategies, including reference condition, passive solar heating condition and active solar heating condition, were tested in one demonstration residential building. The hourly air temperatures of each room under different conditions were obtained and analyzed. The results show the indoor air temperature in the living room and bedrooms (core zones was much higher than that of other rooms under both passive and active solar heating conditions. In addition, the heating effect with different strategies for core zones of the building was evaluated by the ratio of indoor and outdoor degree hour, which indicates that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment. The passive solar heating could undertake 49.8% degree hours for heating under an evaluation criterion of 14 °C and the active solar heating could undertake 75% degree hours for heating under evaluation criterion of 18 °C, which indicated that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment in this area. These findings could provide reference for the design and application of solar heating in similar climate areas.

  17. Epidemiological investigation and risk factors of Echinococcus granulosus in yaks (Bos grunniens), Tibetan pigs and Tibetans on Qinghai Tibetan plateau.

    Science.gov (United States)

    Li, Kun; Zhang, Lihong; Zhang, Hui; Lei, Zhixin; Luo, Houqiang; Mehmood, Khalid; Shahzad, Muhammad; Lan, Yanfang; Wang, Meng; Li, Jiakui

    2017-09-01

    Echinococcus granulosus (E. granulosus) is a diverse zoonotic parasite and causes Cystic echinococcosis (CE) disease in humans and livestock. However, scare information is available about the epidemic situation of E. granulosus infection in yaks, Tibetan pigs and native Tibetans on the Qinghai Tibetan plateau. Therefore, a study was carried out to find prevalence and risk factors of E. granulosus in yaks, Tibetan pigs and Tibetans. Serum samples from yaks (1371), Tibetan pigs (454) and Tibetans (600) were collected and assessed by commercial ELISA kits. Multivariable logistic regression model was performed to find the variables possibly associated with exposure of E. granulosus infection in yaks, Tibetan pigs and Tibetan. The overall prevalence of E. granulosus in yaks was 6.49%. In different regions, the prevalence were ranged from 3.43% to 11.79%. In male and female yaks, the prevalence was 5.67% and 7.04%, respectively. In different ages, the prevalence were ranged from 2.20% to 10.9%. While, in different years, the prevalence was 3.61% in 2014, 9.66% in 2015, and 6.33% in 2016. According to the conditional stepwise logistic regression, three factors (region, age and year) were demonstrated to be risk factors influencing the prevalence of E. granulosus in yaks significantly (Pgranulosus with the distribution of 5.47, 5.70 and 13.27% prevalence in Gongbo'gvamda, Mainling, and Nyingchi region, respectively. In male and female Tibetan pigs, the prevalence was 7.12% and 7.49% respectively, while region was considered as a significant (Pgranulosus infection in Tibetan pigs. The total prevalence of E. granulosus infection in Tibetans was 1.83%, while in male and female Tibetans, the prevalence was 1.41% and 2.21%, respectively. In different ages, the prevalence were ranged from 0 to 3.21%. In Tibetans contacting animals or not was 2.41% and 0.54% respectively, and breeding dogs or not was 3.0% and 1.09%, respectively. Risk factors (gender age, contact animal and breed

  18. The first report of Cryptosporidium spp. in Microtus fuscus (Qinghai vole) and Ochotona curzoniae (wild plateau pika) in the Qinghai-Tibetan Plateau area, China.

    Science.gov (United States)

    Zhang, Xueyong; Jian, Yingna; Li, Xiuping; Ma, Liqing; Karanis, Gabriele; Karanis, Panagiotis

    2018-05-01

    Cryptosporidium is one of the most important genera of intestinal zoonotic pathogens, which can infect various hosts and cause diarrhoea. There is little available information about the molecular characterisation and epidemiological prevalence of Cryptosporidium spp. in Microtus fuscus (Qinghai vole) and Ochotona curzoniae (wild plateau pika) in the Qinghai-Tibetan Plateau area of Qinghai Province, Northwest China. Therefore, the aim of this study was to determine Cryptosporidium species/genotypes and epidemiological prevalence in these mammals by detecting the SSU rRNA gene by PCR amplification. The Cryptosporidium spp. infection rate was 8.9% (8/90) in Qinghai voles and 6.25% (4/64) in wild plateau pikas. Positive samples were successfully sequenced, and the following Cryptosporidium species were found: C. parvum, C. ubiquitum, C. canis and a novel genotype in Qinghai voles and C. parvum and a novel genotype in wild plateau pikas. This is the first report of Cryptosporidium infections in M. fuscus and wild O. curzoniae in Northwest China. The results suggest the possibility of Cryptosporidium species transmission among these two hosts, the environment, other animals and humans and provide useful molecular epidemiological data for the prevention and control of Cryptosporidium infections in wild animals and the surrounding environments. The results of the present study indicate the existence of Cryptosporidium species infections that have potential public health significance. This is the first report of Cryptosporidium multi-species infections in these animal hosts.

  19. Net exchanges of methane and carbon dioxide on the Qinghai-Tibetan Plateau from 1979 to 2100

    International Nuclear Information System (INIS)

    Jin, Zhenong; Zhuang, Qianlai; Zhu, Xudong; He, Jin-Sheng; Song, Weimin

    2015-01-01

    Methane (CH 4 ) is a potent greenhouse gas (GHG) that affects the global climate system. Knowledge about land–atmospheric CH 4 exchanges on the Qinghai-Tibetan Plateau (QTP) is insufficient. Using a coupled biogeochemistry model, this study analyzes the net exchanges of CH 4 and CO 2 over the QTP for the period of 1979–2100. Our simulations show that the region currently acts as a net CH 4 source with 0.95 Tg CH 4 y −1 emissions and 0.19 Tg CH 4 y −1 soil uptake, and a photosynthesis C sink of 14.1 Tg C y −1 . By accounting for the net CH 4 emission and the net CO 2 sequestration since 1979, the region was found to be initially a warming source until the 2010s with a positive instantaneous radiative forcing peak in the 1990s. In response to future climate change projected by multiple global climate models (GCMs) under four representative concentration pathway (RCP) scenarios, the regional source of CH 4 to the atmosphere will increase by 15–77% at the end of this century. Net ecosystem production (NEP) will continually increase from the near neutral state to around 40 Tg C y −1 under all RCPs except RCP8.5. Spatially, CH 4 emission or uptake will be noticeably enhanced under all RCPs over most of the QTP, while statistically significant NEP changes over a large-scale will only appear under RCP4.5 and RCP4.6 scenarios. The cumulative GHG fluxes since 1979 will exert a slight warming effect on the climate system until the 2030s, and will switch to a cooling effect thereafter. Overall, the total radiative forcing at the end of the 21st century is 0.25–0.35 W m −2 , depending on the RCP scenario. Our study highlights the importance of accounting for both CH 4 and CO 2 in quantifying the regional GHG budget. (paper)

  20. Study on the relationship between the lake area variations of Qinghai-Tibetan Plateau and the corresponding climate change in their basins

    Science.gov (United States)

    Guozhuang, Shen; Jingjuan, Liao; Huadong, Guo; Yingkui, Li

    2014-03-01

    Qinghai-Tibetan Plateau is the largest lake area in China, with a total area of existing lakes of 36,900km2, accounting for 52% of the total lake area of China. Lakes on the Tibetan Plateau play critical roles in the water cycle and ecological and environment systems of the Plateau. The global trend of warming up is increasing obviously, which has led to major changes in the climate conditions in China, even in the world. Whereas, when they analyse the relationship they just use the weather station's recording data, without any spatial analysis of the climate data. Here, we will do some researches on the relationship between the 10 selected lakes' area variation and the corresponding climate change in their drainage basin and discuss how the lakes changes in recent 40 years using the climate data processed using the spatial kriging. Thus, the drainage area can be taken into account and a real relationship can be pointed out. In order to study the relationship, Landsat MSS data, Landsat TM, Landsat ETM images, the topographic map have been collected to extract the variation of lake area. The 131 weather stations climate data, including precipitation, temperature, sun shine duration, evaporation are chosen to study the relationship. After extraction of the area of the lakes, a multivariate statistical analysis method was used to test the relationship between the area of the lakes and the global climate change, including the change of the temperature, the precipitation, and other factors. The variation of lakes in Qinghai-Tibetan Plateau is related to the mean temperature, the precipitation and saturation vapour pressure. But the frozen soil may affect the lake area variation to some extent.

  1. Study on the relationship between the lake area variations of Qinghai-Tibetan Plateau and the corresponding climate change in their basins

    International Nuclear Information System (INIS)

    Guozhuang, Shen; Jingjuan, Liao; Huadong, Guo; Yingkui, Li

    2014-01-01

    Qinghai-Tibetan Plateau is the largest lake area in China, with a total area of existing lakes of 36,900km 2 , accounting for 52% of the total lake area of China. Lakes on the Tibetan Plateau play critical roles in the water cycle and ecological and environment systems of the Plateau. The global trend of warming up is increasing obviously, which has led to major changes in the climate conditions in China, even in the world. Whereas, when they analyse the relationship they just use the weather station's recording data, without any spatial analysis of the climate data. Here, we will do some researches on the relationship between the 10 selected lakes' area variation and the corresponding climate change in their drainage basin and discuss how the lakes changes in recent 40 years using the climate data processed using the spatial kriging. Thus, the drainage area can be taken into account and a real relationship can be pointed out. In order to study the relationship, Landsat MSS data, Landsat TM, Landsat ETM images, the topographic map have been collected to extract the variation of lake area. The 131 weather stations climate data, including precipitation, temperature, sun shine duration, evaporation are chosen to study the relationship. After extraction of the area of the lakes, a multivariate statistical analysis method was used to test the relationship between the area of the lakes and the global climate change, including the change of the temperature, the precipitation, and other factors. The variation of lakes in Qinghai-Tibetan Plateau is related to the mean temperature, the precipitation and saturation vapour pressure. But the frozen soil may affect the lake area variation to some extent

  2. Isolation, identification and fibrolytic characteristics of rumen fungi grown with indigenous methanogen from yaks (Bos grunniens) grazing on the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Wei, Y-Q; Yang, H-J; Luan, Y; Long, R-J; Wu, Y-J; Wang, Z-Y

    2016-03-01

    To obtain co-cultures of anaerobic fungi and their indigenously associated methanogens from the rumen of yaks grazing on the Qinghai-Tibetan Plateau and investigate their morphology features and ability to degrade lignocellulose. Twenty fungus-methanogen co-cultures were obtained by Hungate roll-tube technique. The fungi were identified as Orpinomyces, Neocallimastix and Piromyces genera based on the morphological characteristics and internal transcribed spacer 1 sequences analysis. All methanogens were identified as Methanobrevibacter sp. by 16S rRNA gene sequencing. There were four types of co-cultures: Neocallimastix with Methanobrevibacter ruminantium, Orpinomyces with M. ruminantium, Orpinomyces with Methanobrevibacter millerae and Piromyces with M. ruminantium among 20 co-cultures. In vitro studies with wheat straw as substrate showed that the Neocallimastix with M. ruminantium co-cultures and Piromyces with M. ruminantium co-cultures exhibited higher xylanase, filter paper cellulase (FPase), ferulic acid esterase, acetyl esterase activities, in vitro dry matter digestibility, gas, CH4 , acetate production, ferulic acid and p-coumaric acid releases. The Neocallimastix frontalis Yak16 with M. ruminantium co-culture presented the strongest lignocellulose degradation ability among 20 co-cultures. Twenty fungus-methanogen co-cultures were obtained from the rumen of grazing yaks. The N. frontalis with M. ruminantium co-cultures were highly effective combination for developing a fermentative system that bioconverts lignocellulose to high activity fibre-degrading enzyme, CH4 and acetate. The N. frontalis with M. ruminantium co-cultures from yaks grazing on the Qinghai-Tibetan Plateau present great potential in lignocellulose biodegradation industry. © 2015 The Society for Applied Microbiology.

  3. Different responses of ecosystem carbon exchange to warming in three types of alpine grassland on the central Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Ganjurjav, Hasbagan; Hu, Guozheng; Wan, Yunfan; Li, Yue; Danjiu, Luobu; Gao, Qingzhu

    2018-02-01

    Climate is a driver of terrestrial ecosystem carbon exchange, which is an important product of ecosystem function. The Qinghai-Tibetan Plateau has recently been subjected to a marked increase in temperature as a consequence of global warming. To explore the effects of warming on carbon exchange in grassland ecosystems, we conducted a whole-year warming experiment between 2012 and 2014 using open-top chambers placed in an alpine meadow, an alpine steppe, and a cultivated grassland on the central Qinghai-Tibetan Plateau. We measured the gross primary productivity, net ecosystem CO 2 exchange (NEE), ecosystem respiration, and soil respiration using a chamber-based method during the growing season. The results show that after 3 years of warming, there was significant stimulation of carbon assimilation and emission in the alpine meadow, but both these processes declined in the alpine steppe and the cultivated grassland. Under warming conditions, the soil water content was more important in stimulating ecosystem carbon exchange in the meadow and cultivated grassland than was soil temperature. In the steppe, the soil temperature was negatively correlated with ecosystem carbon exchange. We found that the ambient soil water content was significantly correlated with the magnitude of warming-induced change in NEE. Under high soil moisture condition, warming has a significant positive effect on NEE, while it has a negative effect under low soil moisture condition. Our results highlight that the NEE in steppe and cultivated grassland have negative responses to warming; after reclamation, the natural meadow would subject to loose more C in warmer condition. Therefore, under future warmer condition, the overextension of cultivated grassland should be avoided and scientific planning of cultivated grassland should be achieved.

  4. The long-term trends (1982-2006) in vegetation greenness of the alpine ecosystem in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Zhang, Li; Guo, Huadong; Wang, Cuizhen; Ji, Lei; Li, Jing; Wang, Kun; Dai, Lin

    2014-01-01

    The increased rate of annual temperature in the Qinghai-Tibetan Plateau exceeded all other areas of the same latitude in recent decades. The influence of the warming climate on the alpine ecosystem of the plateau was distinct. An analysis of alpine vegetation under changes in climatic conditions was conducted in this study. This was done through an examination of vegetation greenness and its relationship with climate variability using the Advanced Very High Resolution Radiometer satellite imagery and climate datasets. Vegetation in the plateau experienced a positive trend in greenness, with 18.0 % of the vegetated areas exhibiting significantly positive trends, which were primarily located in the eastern and southwestern parts of the plateau. In grasslands, 25.8 % of meadows and 14.1 % of steppes exhibited significant upward trends. In contrast, the broadleaf forests experienced a trend of degradation. Temperature, particularly summer temperature, was the primary factor promoting the vegetation growth in the plateau. The wetter and warmer climate in the east contributed to the favorable conditions for vegetation. The alpine meadow was mostly sensitive to temperature, while the steppes were sensitive to both temperature and precipitation. Although a warming climate was expected to be beneficial to vegetation growth in the alpine region, the rising temperature coupled with reduced precipitation in the south did not favor vegetation growth due to low humidity and poor soil moisture conditions.

  5. Population transcriptomes reveal synergistic responses of DNA polymorphism and RNA expression to extreme environments on the Qinghai-Tibetan Plateau in a predatory bird.

    Science.gov (United States)

    Pan, Shengkai; Zhang, Tongzuo; Rong, Zhengqin; Hu, Li; Gu, Zhongru; Wu, Qi; Dong, Shanshan; Liu, Qiong; Lin, Zhenzhen; Deutschova, Lucia; Li, Xinhai; Dixon, Andrew; Bruford, Michael W; Zhan, Xiangjiang

    2017-06-01

    Low oxygen and temperature pose key physiological challenges for endotherms living on the Qinghai-Tibetan Plateau (QTP). Molecular adaptations to high-altitude living have been detected in the genomes of Tibetans, their domesticated animals and a few wild species, but the contribution of transcriptional variation to altitudinal adaptation remains to be determined. Here we studied a top QTP predator, the saker falcon, and analysed how the transcriptome has become modified to cope with the stresses of hypoxia and hypothermia. Using a hierarchical design to study saker populations inhabiting grassland, steppe/desert and highland across Eurasia, we found that the QTP population is already distinct despite having colonized the Plateau adaptation to hypothermia. Our results exemplify synergistic responses between DNA polymorphism and RNA expression diversity in coping with common stresses, underpinning the successful rapid colonization of a top predator onto the QTP. Importantly, molecular mechanisms underpinning highland adaptation involve relatively few genes, but are nonetheless more complex than previously thought and involve fine-tuned transcriptional responses and genomic adaptation. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  6. Bacterial community in the rumen of Tibetan sheep and Gansu alpine fine-wool sheep grazing on the Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Huang, Jinqiang; Li, Yongjuan; Luo, Yuzhu

    2017-05-12

    The rumen microbiome plays a vital role in ruminant nutrition and health, and its community is affected by environmental factors. However, little is known about the rumen bacterial community of ruminants living in the special ecological environment of the Qinghai-Tibetan Plateau (QTP) of China. The objectives of this study were to investigate the rumen bacterial community of the typical plateau sheep (Tibetan sheep, TS, and Gansu alpine fine-wool sheep, GS) grazing on the QTP, using 16S rRNA gene sequence analysis, and to evaluate the relationship between the rumen bacterial community and the QTP environment. A total of 116 sequences (201 clones) were examined and divided into 53 operational taxonomic units (OTUs) in the TS library and 46 OTUs in the GS library. Phylogenetic analysis showed that the sequences that belonged to the Firmicutes were the most predominant bacteria in both TS and GS libraries, representing 79.4% and 62.8% of the total clones, respectively. The remaining sequences belonged to Bacteroidetes, Proteobacteria, Actinobacteria, or were unclassified bacteria. Sequence analysis revealed that the TS and GS rumens harbored many novel sequences associated with uncultured bacteria that accounted for 63.6% and 46.8% of the total clones, respectively. Comparison of the composition and diversity of the TS and GS rumen bacteria revealed few overlapping known bacteria between the two breeds, and a higher diversity in TS. The rumen bacteria of the plateau sheep showed higher percentages of bacteria that belonged to Firmicutes and novel species compared with the low-elevation sheep. The unique bacterial community in the plateau sheep rumens is perhaps one of the major reasons that they can adapt to the harsh plateau environment. These results can help identify the rumen bacterial community of the ruminants in the QTP, and provide bacteria resources and basic data to improve ruminant productivity.

  7. DNA barcoding of Rhodiola (crassulaceae: a case study on a group of recently diversified medicinal plants from the Qinghai-Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Jian-Qiang Zhang

    Full Text Available DNA barcoding, the identification of species using one or a few short standardized DNA sequences, is an important complement to traditional taxonomy. However, there are particular challenges for barcoding plants, especially for species with complex evolutionary histories. We herein evaluated the utility of five candidate sequences - rbcL, matK, trnH-psbA, trnL-F and the internal transcribed spacer (ITS - for barcoding Rhodiola species, a group of high-altitude plants frequently used as adaptogens, hemostatics and tonics in traditional Tibetan medicine. Rhodiola was suggested to have diversified rapidly recently. The genus is thus a good model for testing DNA barcoding strategies for recently diversified medicinal plants. This study analyzed 189 accessions, representing 47 of the 55 recognized Rhodiola species in the Flora of China treatment. Based on intraspecific and interspecific divergence and degree of monophyly statistics, ITS was the best single-locus barcode, resolving 66% of the Rhodiola species. The core combination rbcL+matK resolved only 40.4% of them. Unsurprisingly, the combined use of all five loci provided the highest discrimination power, resolving 80.9% of the species. However, this is weaker than the discrimination power generally reported in barcoding studies of other plant taxa. The observed complications may be due to the recent diversification, incomplete lineage sorting and reticulate evolution of the genus. These processes are common features of numerous plant groups in the high-altitude regions of the Qinghai-Tibetan Plateau.

  8. Permafrost collapse shifts alpine tundra to a carbon source but reduces N2O and CH4 release on the northern Qinghai-Tibetan Plateau

    Science.gov (United States)

    Mu, C.

    2017-12-01

    Important unknowns remain about how abrupt permafrost collapse (thermokarst) affects carbon balance and greenhouse gas flux, limiting our ability to predict the magnitude and timing of the permafrost carbon feedback. We measured monthly, growing-season fluxes of CO2, CH4, and N2O at a large thermokarst feature in alpine tundra on the northern Qinghai-Tibetan Plateau (QTP). Thermokarst formation disrupted plant growth and soil hydrology, shifting the ecosystem from a growing-season carbon sink to a weak source, but decreasing feature-level CH4 and N2O flux. Temperature-corrected ecosystem respiration from decomposing permafrost soil was 2.7 to 9.5-fold higher than in similar features from Arctic and Boreal regions, suggesting that warmer and dryer conditions on the northern QTP could accelerate carbon decomposition following permafrost collapse. N2O flux was similar to the highest values reported for Arctic ecosystems, and was 60% higher from exposed mineral soil on the feature floor, confirming Arctic observations of coupled nitrification and denitrification in collapsed soils. Q10 values for respiration were typically over 4, suggesting high temperature sensitivity of thawed carbon. Taken together, these results suggest that QTP permafrost carbon in alpine tundra is highly vulnerable to mineralization following thaw, and that N2O production could be an important non-carbon permafrost climate feedback.

  9. The response of lake area and vegetation cover variations to climate change over the Qinghai-Tibetan Plateau during the past 30years.

    Science.gov (United States)

    Zhang, Zengxin; Chang, Juan; Xu, Chong-Yu; Zhou, Yang; Wu, Yanhong; Chen, Xi; Jiang, Shanshan; Duan, Zheng

    2018-09-01

    Lakes and vegetation are important factors of the Earth's hydrological cycle and can be called an "indicator" of climate change. In this study, long-term changes of lakes' area and vegetation coverage in the Qinghai-Tibetan Plateau (QTP) and their relations to the climate change were analyzed by using Mann-Kendall method during the past 30years. Results showed that: 1) the lakes' area of the QTP increased significantly during the past 30years as a whole, and the increasing rates have been dramatically sped up since the year of 2000. Among them, the area of Ayakekumu Lake has the fastest growing rate of 51.35%, which increased from 618km 2 in the 1980s to 983km 2 in the 2010s; 2) overall, the Normalized Difference Vegetation Index (NDVI) increased in the QTP during the past 30years. Above 79% of the area in the QTP showed increasing trend of NDVI before the year of 2000; 3) the air temperature increased significantly, the precipitation increased slightly, and the pan evaporation decreased significantly during the past 30years. The lake area and vegetation coverage changes might be related to the climate change. The shifts in the temporal climate trend occurred around the year 2000 had led the lake area and vegetation coverage increasing. This study is of importance in further understanding the environmental changes under global warming over the QTP. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Three-dimensional framework of vigor, organization, and resilience (VOR) for assessing rangeland health: a case study from the alpine meadow of the Qinghai-Tibetan Plateau, China.

    Science.gov (United States)

    Li, Yuan-yuan; Dong, Shi-kui; Wen, Lu; Wang, Xue-xia; Wu, Yu

    2013-12-01

    Rangeland health assessments play an important role in providing qualitative and quantitative data about ecosystem attributes and rangeland management. The objective of this study is to test the feasible of a modified model and visualize the health in a three-dimensional model. A modified Costanza model was employed, and eight indicators, including the biomass, biodiversity, and carrying capacity [associated with the vigor, organization, and resilience (VOR)] were applied. An entropy method was also developed to calculate the weight of each indicator, and a three-dimensional framework was applied to visualize the indicators and health index. The conceptual model was demonstrated using data from a case study on the alpine rangeland of the Qinghai-Tibetan Plateau, one of the globally important grassland biomes being severely degraded by natural and human factors. The health indices of four grassland plots at different levels of degradation were calculated using a modified approach to measuring their VOR. The results indicated that the least disturbed plot was relatively healthy compared to the other plots. In addition, the health indices presented in the three-dimensional VOR framework decreased in a consistent manner across the four plots along the disturbance gradients. Such rangeland health assessments should be integrated with management efforts to insure their long-term sustainable use.

  11. Dissolved organic carbon, CO2, and CH4 concentrations and their stable isotope ratios in thermokarst lakes on the Qinghai-Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Cuicui Mu

    2016-01-01

    Full Text Available Thermokarst lakes are widely distributed on the Qinghai-Tibetan Plateau (QTP, which accounts for 8% of the global permafrost area. These lakes probably promote organic matter biodegradation and thus accelerate the emission of carbon-based greenhouse gases. However, little is known about greenhouse gas concentrations and their stable isotopes characteristics of these lakes. In this study, we measured the concentrations of dissolved organic carbon (DOC, dissolved CO2 and CH4, as well as the distribution of δ13CCO2, δ13CCH4, and δ13COM (organic matter of lake sediments in thermokarst lakes on the QTP. Results showed that the OM of the lake sediments was highly decomposed. The concentrations of DOC, CO2 and CH4 in the lake water on the QTP were 1.2–49.6 mg L–1, 3.6–45.0 μmol L–1 and 0.28–3.0 μmol L–1, respectively. The highest CO2 and CH4 concentrations were recorded in July while the lowest values in September, which suggested that temperature had an effect on greenhouse gas production, although this pattern may also relate to thermal stratification of the water column. The results implied that thermokast lakes should be paid more attention to regarding carbon cycle and greenhouse gas emissions on the QTP.

  12. Influence of land cover on riverine dissolved organic carbon concentrations and export in the Three Rivers Headwater Region of the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Ma, Xiaoliang; Liu, Guimin; Wu, Xiaodong; Smoak, Joseph M; Ye, Linlin; Xu, Haiyan; Zhao, Lin; Ding, Yongjian

    2018-07-15

    The Qinghai-Tibetan plateau (QTP) stores a large amount of soil organic carbon and is the headwater region for several large rivers in Asia. Therefore, it is important to understand the influence of environmental factors on river water quality and the dissolved organic carbon (DOC) export in this region. We examined the water physico-chemical characteristics, DOC concentrations and export rates of 7 rivers under typical land cover types in the Three Rivers Headwater Region during August 2016. The results showed that the highest DOC concentrations were recorded in the rivers within the catchment of alpine wet meadow and meadow. These same rivers had the lowest total suspended solids (TSS) concentrations. The rivers within steppe and desert had the lowest DOC concentrations and highest TSS concentrations. The discharge rates and catchment areas were negatively correlated with DOC concentrations. The SUVA 254 values were significantly negatively correlated with DOC concentrations. The results suggest that the vegetation degradation, which may represent permafrost degradation, can lead to a decrease in DOC concentration, but increasing DOC export and soil erosion. In addition, some of the exported DOC will rapidly decompose in the river, and therefore affect the regional carbon cycle, as well as the water quality in the source water of many large Asian rivers. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Are land use and short time climate change effective on soil carbon compositions and their relationships with soil properties in alpine grassland ecosystems on Qinghai-Tibetan Plateau?

    Science.gov (United States)

    Zhao, Zhenzhen; Dong, Shikui; Jiang, Xiaoman; Zhao, Jinbo; Liu, Shiliang; Yang, Mingyue; Han, Yuhui; Sha, Wei

    2018-06-01

    Fencing and grass plantation are two key interventions to preserve the degraded grassland on the Qinghai-Tibetan Plateau (QTP). Climate warming and N deposition have substantially affected the alpine grassland ecosystems. However, molecular composition of soil organic carbon (SOC), the indicator of degradation of SOC, and its responses to climate change are still largely unclear. In this study, we conducted the experiments in three types of land use on the QTP: alpine meadow (AM), alpine steppe (AS), and cultivated grassland (CG) under 2°C climatic warming, 5 levels of nitrogen deposition rates at 8, 24, 40, 56, and 72kg N ha -1 year -1 , as well as a combination of climatic warming and N deposition (8kg N ha -1 year -1 ). Our findings indicate that all three types of land use were dominated by O-alkyl carbon. The alkyl/O-alkyl ratio, aromaticity and hydrophobicity index of the CG were larger than those of the AM and AS, and this difference was generally stable under different treatments. Most of the SOC in the alpine grasslands was derived from fresh plants, and the carbon in the CG was more stable than that in the AM and AS. The compositions of all the alpine ecosystems were stable under short-term climatic changes, suggesting the short-term climate warming and nitrogen deposition likely did not affect the molecular composition of the SOC in the restored grasslands. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Hydromagnesite precipitation in the Alkaline Lake Dujiali, central Qinghai-Tibetan Plateau: Constraints on hydromagnesite precipitation from hydrochemistry and stable isotopes

    International Nuclear Information System (INIS)

    Lin, Yongjie; Zheng, Mianping; Ye, Chuanyong

    2017-01-01

    The mineral hydromagnesite, Mg 5 (CO 3 ) 4 (OH) 2 ·4H 2 O, is a common form of hydrated Mg-carbonate in alkaline lakes, yet the processes involved in its formation are not well understood. This study focuses on Dujiali Lake, in the central Qinghai-Tibetan Plateau (QTP), which is one of the few environments on the earth's surface with extensive Holocene precipitation of hydromagnesite. The hydrogeochemistry of surface waters, and the mineralogical, stable isotope (δ 13 C and δ 18 O), and radiogenic isotope content of hydromagnesite deposits were analyzed to investigate formation mechanisms. The chemical composition of surface water around Dujiali Lake evolved from the rock-weathering-type waters of T1 (Ca−Mg−HCO 3 water type) to more concentrated sodic waters of T2 (Na−SO 4 −Cl water type) due to evaporation. XRD results show that the mineralogical composition of samples is pure hydromagnesite. Analysis of oxygen isotopes in the hydromagnesite indicates that supergene formation with authigenic carbonate crystallization from evaporation water is the dominant precipitation process. Combined carbon-oxygen isotope analysis suggests atmospheric CO 2 provided a carbon source for the precipitation of hydromagnesite. These findings suggest that hydromagnesite precipitation at Lake Dujiali is mainly inorganic in nature, and the greenhouse gas, CO 2 , is trapped and stored in the hydromagnesite directly from the atmosphere. AMS radiocarbon dating of samples indicates CO 2 was sequestered between 5845 ± 30 to 6090 ± 25 cal a BP in the Dujiali Lake hydromagnesite deposit. The study contributes to improved understanding of hydromagnesite formation in modern and ancient playas. - Highlights: • The stable isotopes, radiogenic isotope data are firstly obtained from the hydromagnesite deposits of Lake Dujiali in QTP. • Hydromagnesite precipitation at Lake Dujiali is mainly inorganic. • δ 18 O indicates supergene formation with authigenic carbonate

  15. Spatial pattern and variations in the prevalence of congenital heart disease in children aged 4-18 years in the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Ma, Li-Guang; Chen, Qiu-Hong; Wang, Yuan-Yuan; Wang, Jing; Ren, Zhou-Peng; Cao, Zong-Fu; Cao, Yan-Rong; Ma, Xu; Wang, Bin-Bin

    2018-06-15

    This study aimed to investigate the spatial distribution pattern of the prevalence of congenital heart disease (CHD) in children in Qinghai-Tibetan Plateau (QTP), a high-altitude region in China. Epidemiological data from a survey on the prevalence of CHD in Qinghai Province including 288,066 children (4-18 years) were used in this study. The prevalence and distribution pattern of CHD was determined by sex, CHD subtype, and nationality and altitude. Spatial pattern analysis using Getis-Ord Gi ⁎ was used to identify the spatial distribution of CHD. Bayesian spatial binomial regression was performed to examine the relationship between the prevalence of CHD and environmental risk factors in the QTP. The prevalence of CHD showed a significant spatial clustering pattern. The Tibetan autonomous prefecture of Yushu (average altitude > 4000 m) and the Mongolian autonomous county of Henan (average altitude > 3600 m) in Huangnan had the highest prevalence of CHD. Univariate analysis showed that with ascending altitude, the total prevalence of CHD, that in girls and boys with CHD, and that of the subtypes PDA and ASD increasing accordingly. Thus, environmental factors greatly contributed to the prevalence of CHD. The prevalence of CHD shows significant spatial clustering pattern in the QTP. The CHD subtype prevalence clustering pattern has statistical regularity which would provide convenient clues of environmental risk factors. Our results may provide support to make strategies of CHD prevention, to reduce the incidence of CHD in high altitude regions of China. Copyright © 2018. Published by Elsevier B.V.

  16. Representing the effects of alpine grassland vegetation cover on the simulation of soil thermal dynamics by ecosystem models applied to the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Yi, S.; Li, N.; Xiang, B.; Wang, X.; Ye, B.; McGuire, A.D.

    2013-01-01

    Soil surface temperature is a critical boundary condition for the simulation of soil temperature by environmental models. It is influenced by atmospheric and soil conditions and by vegetation cover. In sophisticated land surface models, it is simulated iteratively by solving surface energy budget equations. In ecosystem, permafrost, and hydrology models, the consideration of soil surface temperature is generally simple. In this study, we developed a methodology for representing the effects of vegetation cover and atmospheric factors on the estimation of soil surface temperature for alpine grassland ecosystems on the Qinghai-Tibetan Plateau. Our approach integrated measurements from meteorological stations with simulations from a sophisticated land surface model to develop an equation set for estimating soil surface temperature. After implementing this equation set into an ecosystem model and evaluating the performance of the ecosystem model in simulating soil temperature at different depths in the soil profile, we applied the model to simulate interactions among vegetation cover, freeze-thaw cycles, and soil erosion to demonstrate potential applications made possible through the implementation of the methodology developed in this study. Results showed that (1) to properly estimate daily soil surface temperature, algorithms should use air temperature, downward solar radiation, and vegetation cover as independent variables; (2) the equation set developed in this study performed better than soil surface temperature algorithms used in other models; and (3) the ecosystem model performed well in simulating soil temperature throughout the soil profile using the equation set developed in this study. Our application of the model indicates that the representation in ecosystem models of the effects of vegetation cover on the simulation of soil thermal dynamics has the potential to substantially improve our understanding of the vulnerability of alpine grassland ecosystems to

  17. Contributions of air pollution and climate warming to tufa wetland degradation in Jiuzhaigou National Nature Reserve, eastern rim of the Qinghai-Tibetan Plateau, China

    Science.gov (United States)

    Qiao, X.; Tang, Y.

    2017-12-01

    Massive deposition of calcium carbonate in ambient temperature waters forms magnificent tufa wetlands, many of which are designated as protected areas and are popular tourist destinations. There is a tufa wetland belt along the Eastern Rim of the Qinghai-Tibetan Plateau (ERQTP), and many of them are experiencing degradation, such as nutrient enrichment and tufa degradation. Meanwhile, there is also an air pollution belt in the ERQTP. This study was made to understand the correlation of tufa wetland degradation with climate change and air pollution for Jiuzhaigou National Nature Reserve (hereafter Jiuzhaigou). Atmospheric changes were first studied. The results show that annual mean air temperature increased by 1.2oC from 1951 to 2014. Anthropogenic emissions contributed to over 90% annual wet deposition fluxes of reactive sulfur and nitrogen and caused acid rain (pHpollutants. Then, the impacts of air pollution and climate warming on tufa wetlands were further investigated. We found that precipitation was calcite-unsaturated so it could dissolve exposed tufa and considerably reduce tufa deposition rate and even cause tufa dissolution in shallow waters. These effects enhanced as precipitation pH decreased. Annual volume-weighted mean concentration of reactive nitrogen in wet deposition and runoff were 26.1 and 14.8 µmol L-1, respectively, both exceeding China's national standard of total nitrogen in runoff for nature reserves (14.3 µmol L-1) and this suggested a nitrogen fertilization effect of wet deposition on green algae. As water temperature is the limiting factor of algal growth in Jiuzhaigou and temperature in the top layer (0-5 cm) of runoff (with a depthpollutants have contributed to tufa wetland degradation in Jiuzhaigou, but in order to better quantify the contributions, further studies are needed, as many other anthropogenic and natural processes also influence tufa wetland evolution.

  18. Interaction of CARD14, SENP1 and VEGFA polymorphisms on susceptibility to high altitude polycythemia in the Han Chinese population at the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Chen, Yu; Jiang, Chunhua; Luo, Yongjun; Liu, Fuyu; Gao, Yuqi

    2016-03-01

    High altitude polycythemia (HAPC) is a serious public health problem among Han Chinese immigrants to the Qinghai-Tibetan Plateau. This study aims to explore the genetic basis of HAPC in the Han Chinese population. 484 male subjects (234 patients and 250 controls) were enrolled in this study. Genotyping was performed for polymorphisms of I/D in ACE, C1772T and G1790A in exon 12 of HIF-1α, rs2567206 in CYP1B1, rs726354 in SENP1, rs3025033 in VEGFA, rs7251432 in HAMP, rs2075800 in HSPA1L and rs8065364 in CARD14. Gene-gene interaction was assessed by multifactor dimensionality reduction. A significant association was seen between CARD14 polymorphism rs8065364 and risk of HAPC development in male Han Chinese, and the C allele of rs8065364 was a risk factor (odds ratio (OR)=1.59, 95% confidence interval (95% CI)=1.21-2.08). Gene-gene interaction analysis indicated that a synergistic relationship existed between rs3025033 and rs8065364 (1.00%), rs3025033 and rs726354 (0.18%), and rs726354 and rs8065364 (0.17%). The combination of rs8065364 in CARD14, rs3025033 in VEGFA and rs726354 in SENP1 was the best model to predict HAPC development in this study (testing accuracy=0.6183, p=0.0010, cross-validated consistency=10/10). Genetic interactions of SNPs in CARD14, SENP1 and VEGFA might represent a functional mechanism in the pathogenesis of HAPC. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Diurnal and Seasonal Variations in the Net Ecosystem CO2 Exchange of a Pasture in the Three-River Source Region of the Qinghai-Tibetan Plateau.

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    Bin Wang

    Full Text Available Carbon dioxide (CO2 exchange between the atmosphere and grassland ecosystems is very important for the global carbon balance. To assess the CO2 flux and its relationship to environmental factors, the eddy covariance method was used to evaluate the diurnal cycle and seasonal pattern of the net ecosystem CO2 exchange (NEE of a cultivated pasture in the Three-River Source Region (TRSR on the Qinghai-Tibetan Plateau from January 1 to December 31, 2008. The diurnal variations in the NEE and ecosystem respiration (Re during the growing season exhibited single-peak patterns, the maximum and minimum CO2 uptake observed during the noon hours and night; and the maximum and minimum Re took place in the afternoon and early morning, respectively. The minimum hourly NEE rate and the maximum hourly Re rate were -7.89 and 5.03 μmol CO2 m-2 s-1, respectively. The NEE and Re showed clear seasonal variations, with lower values in winter and higher values in the peak growth period. The highest daily values for C uptake and Re were observed on August 12 (-2.91 g C m-2 d-1 and July 28 (5.04 g C m-2 day-1, respectively. The annual total NEE and Re were -140.01 and 403.57 g C m-2 year-1, respectively. The apparent quantum yield (α was -0.0275 μmol μmol-1 for the entire growing period, and the α values for the pasture's light response curve varied with the leaf area index (LAI, air temperature (Ta, soil water content (SWC and vapor pressure deficit (VPD. Piecewise regression results indicated that the optimum Ta and VPD for the daytime NEE were 14.1°C and 0.65 kPa, respectively. The daytime NEE decreased with increasing SWC, and the temperature sensitivity of respiration (Q10 was 3.0 during the growing season, which was controlled by the SWC conditions. Path analysis suggested that the soil temperature at a depth of 5 cm (Tsoil was the most important environmental factor affecting daily variations in NEE during the growing season, and the photosynthetic photon

  20. Quantifying species diversity with a DNA barcoding-based method: Tibetan moth species (Noctuidae on the Qinghai-Tibetan Plateau.

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    Qian Jin

    Full Text Available With the ongoing loss of biodiversity, there is a great need for fast and effective ways to assess species richness and diversity: DNA barcoding provides a powerful new tool for this. We investigated this approach by focusing on the Tibetan plateau, which is one of the world's top biodiversity hotspots. There have been few studies of its invertebrates, although they constitute the vast majority of the region's diversity. Here we investigated species diversity of the lepidopteran family Noctuidae, across different environmental gradients, using measurements based on traditional morphology as well as on DNA barcoding. The COI barcode showed an average interspecific K2P distance of 9.45±2.08%, which is about four times larger than the mean intraspecific distance (1.85±3.20%. Using six diversity indices, we did not detect any significant differences in estimated species diversity between measurements based on traditional morphology and on DNA barcoding. Furthermore, we found strong positive correlations between them, indicating that barcode-based measures of species diversity can serve as a good surrogate for morphology-based measures in most situations tested. Eastern communities were found to have significantly higher diversity than Western ones. Among 22 environmental factors tested, we found that three (precipitation of driest month, precipitation of driest quarter, and precipitation of coldest quarter were significantly correlated with species diversity. Our results indicate that these factors could be the key ecological factors influencing the species diversity of the lepidopteran family Noctuidae on the Tibetan plateau.

  1. Quantifying Species Diversity with a DNA Barcoding-Based Method: Tibetan Moth Species (Noctuidae) on the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Jin, Qian; Han, Huilin; Hu, XiMin; Li, XinHai; Zhu, ChaoDong; Ho, Simon Y. W.; Ward, Robert D.; Zhang, Ai-bing

    2013-01-01

    With the ongoing loss of biodiversity, there is a great need for fast and effective ways to assess species richness and diversity: DNA barcoding provides a powerful new tool for this. We investigated this approach by focusing on the Tibetan plateau, which is one of the world's top biodiversity hotspots. There have been few studies of its invertebrates, although they constitute the vast majority of the region's diversity. Here we investigated species diversity of the lepidopteran family Noctuidae, across different environmental gradients, using measurements based on traditional morphology as well as on DNA barcoding. The COI barcode showed an average interspecific K2P distance of , which is about four times larger than the mean intraspecific distance (). Using six diversity indices, we did not detect any significant differences in estimated species diversity between measurements based on traditional morphology and on DNA barcoding. Furthermore, we found strong positive correlations between them, indicating that barcode-based measures of species diversity can serve as a good surrogate for morphology-based measures in most situations tested. Eastern communities were found to have significantly higher diversity than Western ones. Among 22 environmental factors tested, we found that three (precipitation of driest month, precipitation of driest quarter, and precipitation of coldest quarter) were significantly correlated with species diversity. Our results indicate that these factors could be the key ecological factors influencing the species diversity of the lepidopteran family Noctuidae on the Tibetan plateau. PMID:23741330

  2. Vegetation Changes in the Permafrost Regions of the Qinghai-Tibetan Plateau from 1982-2012: Different Responses Related to Geographical Locations and Vegetation Types in High-Altitude Areas.

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    Zhiwei Wang

    Full Text Available The Qinghai-Tibetan Plateau (QTP contains the largest permafrost area in a high-altitude region in the world, and the unique hydrothermal environments of the active layers in this region have an important impact on vegetation growth. Geographical locations present different climatic conditions, and in combination with the permafrost environments, these conditions comprehensively affect the local vegetation activity. Therefore, the responses of vegetation to climate change in the permafrost region of the QTP may be varied differently by geographical location and vegetation condition. In this study, using the latest Global Inventory Modeling and Mapping Studies (GIMMS Normalized Difference Vegetation Index (NDVI product based on turning points (TPs, which were calculated using a piecewise linear model, 9 areas within the permafrost region of the QTP were selected to investigate the effect of geographical location and vegetation type on vegetation growth from 1982 to 2012. The following 4 vegetation types were observed in the 9 selected study areas: alpine swamp meadow, alpine meadow, alpine steppe and alpine desert. The research results show that, in these study areas, TPs mainly appeared in 2000 and 2001, and almost 55.1% and 35.0% of the TPs were located in 2000 and 2001. The global standardized precipitation evapotranspiration index (SPEI and 7 meteorological variables were selected to analyze their correlations with NDVI. We found that the main correlative variables to vegetation productivity in study areas from 1982 to 2012 were precipitation, surface downward long-wave radiation and temperature. Furthermore, NDVI changes exhibited by different vegetation types within the same study area followed similar trends. The results show that regional effects rather than vegetation type had a larger impact on changes in vegetation growth in the permafrost regions of the QTP, indicating that climatic factors had a larger impact in the permafrost

  3. Advance in the Reasons for Two Different Grassland Use Patterns Formed and Their Each Effects on the Socio-ecological System on the Qinghai-Tibetan Plateau%青藏高原不同草地利用方式产生的原因及其对社会-生态系统的影响研究进展

    Institute of Scientific and Technical Information of China (English)

    曹建军; 许雪贇; 杨书荣; 李梦天; 龚毅帆; 周俊菊

    2017-01-01

    In 1990s,grassland contract system was introduced in Qinghai-Tibetan Plateau,but it has not been implemented thoroughly due to some reasons,and thus two distinct patterns of grassland contract emerged:the multi-household use pattern (MUP) that the grasslands were jointly managed by two or more households without fences between individual household pastures and the single-household use pattern (SUP) that grasslands were managed by individual household with fences demarcating the individual ownership.The reasons of these two patterns and their effects on socio-ecological system caused a wide concern,and researchers have extensively studied in recent years.In this paper,the major progress in this field is reviewed,extensive literature is analyzed and summed up,and common issues in present studies are discussed.In current studies,it lacks of the study in the advantages of the SUP and the weaknesses of MUP,and the coupled socio-ecological systems and properties in this special area are not fully concerned.Based on this,the paper lists several aspects that should be paid more attention in future study,such as the external reasons leading to the emergence of the SUP,possible consequences caused by the SUP,comparative study between the SUP and the MUP according to ecology,economy,society and culture,and the optimum number of households in the MUP.%20世纪90年代,青藏高原地区开始推行草地承包到户制度,但因种种原因,草地承包落实并不彻底,出现了单户利用和联户利用共存的局面.两种利用方式产生的原因及各自对社会-生态系统的影响引起了学术界的高度关注,已有众多研究人员对此问题进行了深入研究.论文通过对国内外相关文献的分析和总结,对这一研究领域中所取得的主要进展进行了回顾,并凝练出其中存在的主要问题,如对单户利用正面影响和对联户利用负面影响的认识不足等.在此基础上,有针对性地指出了未来研究应予

  4. Salinity shapes microbial diversity and community structure in surface sediments of the Qinghai-Tibetan Lakes.

    Science.gov (United States)

    Yang, Jian; Ma, Li'an; Jiang, Hongchen; Wu, Geng; Dong, Hailiang

    2016-04-26

    Investigating microbial response to environmental variables is of great importance for understanding of microbial acclimatization and evolution in natural environments. However, little is known about how microbial communities responded to environmental factors (e.g. salinity, geographic distance) in lake surface sediments of the Qinghai-Tibetan Plateau (QTP). In this study, microbial diversity and community structure in the surface sediments of nine lakes on the QTP were investigated by using the Illumina Miseq sequencing technique and the resulting microbial data were statistically analyzed in combination with environmental variables. The results showed total microbial community of the studied lakes was significantly correlated (r = 0.631, P diversity and community structure in the studied samples. In addition, the abundant and rare taxa (OTUs with relative abundance higher than 1% and lower than 0.01% within one sample, respectively) were significantly (P < 0.05) correlated (r = 0.427 and 0.783, respectively) with salinity, suggesting rare taxa might be more sensitive to salinity than their abundant counterparts, thus cautions should be taken in future when evaluating microbial response (abundant vs. rare sub-communities) to environmental conditions.

  5. Molecular evolution of myoglobin in the Tibetan Plateau endemic schizothoracine fish (Cyprinidae, Teleostei) and tissue-specific expression changes under hypoxia.

    Science.gov (United States)

    Qi, Delin; Chao, Yan; Zhao, Yongli; Xia, Mingzhe; Wu, Rongrong

    2018-04-01

    Myoglobin (Mb) is an oxygen-binding hemoprotein that was once thought to be exclusively expressed in oxidative myocytes of skeletal and cardiac muscle where it serves in oxygen storage and facilitates intracellular oxygen diffusion. In this study, we cloned the coding sequence of the Mb gene from four species, representing three groups, of the schizothoracine fish endemic to the Qinghai-Tibetan Plateau (QTP), then conducted molecular evolution analyses. We also investigated tissue expression patterns of Mb and the expression response to moderate and severe hypoxia at the mRNA and protein levels in a representative of the highly specialized schizothoracine fish species, Schizopygopsis pylzovi. Molecular evolution analyses showed that Mb from the highly specialized schizothoracine fish have undergone positive selection and one positively selected residue (81L) was identified, which is located in the F helix, close to or in contact with the heme. We present tentative evidence that the Mb duplication event occurred in the ancestor of the schizothoracine and Cyprininae fish (common carp and goldfish), and that the Mb2 paralog was subsequently lost in the schizothoracine fish. In S. pylzovi, Mb mRNA is expressed in various tissues with the exception of the intestine and gill, but all such tissues, including the liver, muscle, kidney, brain, eye, and skin, expressed very low levels of Mb mRNA (Tibetan Plateau fish.

  6. Recent geological events and intrinsic behavior influence the population genetic structure of the chiru and tibetan gazelle on the tibetan plateau.

    Science.gov (United States)

    Zhang, Fangfang; Jiang, Zhigang; Xu, Aichun; Zeng, Yan; Li, Chunwang

    2013-01-01

    The extent to which a species responds to environmental changes is mediated not only by extrinsic processes such as time and space, but also by species-specific ecology. The Qinghai-Tibetan Plateau uplifted approximately 3000 m and experienced at least four major glaciations during the Pleistocene epoch in the Quaternary Period. Consequently, the area experienced concurrent changes in geomorphological structure and climate. Two species, the Tibetan antelope (Pantholops hodgsonii, chiru) and Tibetan gazelle (Procapra picticaudata), both are endemic on the Qinghai-Tibetan Plateau, where their habitats overlap, but have different migratory behaviors: the chiru is inclined to have female-biased dispersal with a breeding migration during the calving season; in contrast, Tibetan gazelles are year-round residents and never migrate distantly. By using coalescence methods we compared mitochondrial control region DNA sequences and variation at nine microsatellite loci in these two species. Coalescent simulations indicate that the chiru and Tibetan gazelle do not share concordant patterns in their genealogies. The non-migratory Tibetan gazelle, that is more vulnerable to the impact of drastic geographic changes such as the elevation of the plateau, glaciations and so on, appears to have a strong population genetic structure with complicated demographic history. Specifically, the Tibetan gazelle population appears to have experienced isolation and divergence with population fluctuations since the Middle Pleistocene (0.781 Ma). However, it showed continued decline since the Upper Pleistocene (0.126 Ma), which may be attributed to the irreversible impact of increased human activities on the plateau. In contrast, the migratory chiru appears to have simply experienced population expansion. With substantial gene flow among regional populations, this species shows no historical population isolation and divergence. Thus, this study adds to many empirical studies that show historical

  7. Modeling impacts of climate change and grazing effects on plant biomass and soil organic carbon in the Qinghai-Tibetan grasslands

    Science.gov (United States)

    Zhang, Wenjuan; Zhang, Feng; Qi, Jiaguo; Hou, Fujiang

    2017-12-01

    The Qinghai Province supports over 40 % of the human population of the Qinghai-Tibetan Plateau (QTP) but occupies about 29 % of its land area, and thus it plays an important role in the plateau. The dominant land cover is grassland, which has been severely degraded over the last decade due to a combination of increased human activities and climate change. Numerous studies indicate that the plateau is sensitive to recent global climate change, but the drivers and consequences of grassland ecosystem change are controversial, especially the effects of climate change and grazing patterns on the grassland biomass and soil organic carbon (SOC) storage in this region. In this study, we used the DeNitrification-DeComposition (DNDC) model and two climate change scenarios (representative concentration pathways: RCP4.5 and RCP8.5) to understand how the grassland biomass and SOC pools might respond to different grazing intensities under future climate change scenarios. More than 1400 grassland biomass sampling points and 46 SOC points were used to validate the simulated results. The simulated above-ground biomass and SOC concentrations were in good agreement with the measured data (R2 0.71 and 0.73 for above-ground biomass and SOC, respectively). The results showed that climate change may be the major factor that leads to fluctuations in the grassland biomass and SOC, and it explained 26.4 and 47.7 % of biomass and SOC variation, respectively. Meanwhile, the grazing intensity explained 6.4 and 2.3 % variation in biomass and SOC, respectively. The project average biomass and SOC between 2015 and 2044 was significantly smaller than past 30 years (1985-2014), and it was 191.17 g C m-2, 63.44 g C kg-1 and 183.62 g C m-2, 63.37 g C kg-1 for biomass and SOC under RCP4.5 and RCP8.5, respectively. The RCP8.5 showed the more negative effect on the biomass and SOC compared with RCP4.5. Grazing intensity had a negative relationship with biomass and positive relationship with SOC

  8. A Complex System of Glacial Sub-Refugia Drives Endemic Freshwater Biodiversity on the Tibetan Plateau.

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    Clewing, Catharina; Albrecht, Christian; Wilke, Thomas

    2016-01-01

    Although only relatively few freshwater invertebrate families are reported from the Tibetan Plateau, the degree of endemism may be high. Many endemic lineages occur within permafrost areas, raising questions about the existence of isolated intra-plateau glacial refugia. Moreover, if such refugia existed, it might be instructive to learn whether they were associated with lakes or with more dynamic ecosystems such as ponds, wetlands, or springs. To study these hypotheses, we used pulmonate snails of the plateau-wide distributed genus Radix as model group and the Lake Donggi Cona drainage system, located in the north-eastern part of the plateau, as model site. First, we performed plateau-wide phylogenetic analyses using mtDNA data to assess the overall relationships of Radix populations inhabiting the Lake Donggi Cona system for revealing refugial lineages. We then conducted regional phylogeographical analyses applying a combination of mtDNA and nuclear AFLP markers to infer the local structure and demographic history of the most abundant endemic Radix clade for identifying location and type of (sub-)refugia within the drainage system. Our phylogenetic analysis showed a high diversity of Radix lineages in the Lake Donggi Cona system. Subsequent phylogeographical analyses of the most abundant endemic clade indicated a habitat-related clustering of genotypes and several Late Pleistocene spatial/demographic expansion events. The most parsimonious explanation for these patterns would be a scenario of an intra-plateau glacial refugium in the Lake Donggi Cona drainage system, which might have consisted of isolated sub-refugia. Though the underlying processes remain unknown, an initial separation of lake and watershed populations could have been triggered by lake-level fluctuations before and during the Last Glacial Maximum. This study inferred the first intra-plateau refugium for freshwater animals on the Tibetan Plateau. It thus sheds new light on the evolutionary history

  9. Impacts of altitude and position on the rates of soil nitrogen mineralization and nitrification in alpine meadows on the eastern Qinghai-Tibetan Plateau, China

    Science.gov (United States)

    Alpine and tundra grasslands constitute 7% world terrestrial land but 13% of the total global soil carbon (C) and 10% of the global soil nitrogen (N). Under the current climate change scenario of global warming, these grasslands will contribute significantly to the changing global C and N cycles. It...

  10. Phylogeographic investigation and ecological niche modelling of the endemic frog species Nanorana pleskei revealed multiple refugia in the eastern Tibetan Plateau.

    Science.gov (United States)

    Wang, Bin; Xie, Feng; Li, Jiannan; Wang, Gang; Li, Cheng; Jiang, Jianping

    2017-01-01

    The largest plateau Tibetan Plateau supplied an excellent opportunity to investigate the influence of the Pleistocene events on the high-elevation species. To test for the alternative hypotheses of Pleistocene glacial refugia, we used partial sequences of two mitochondrial genes and one nuclear gene to examine the phylogeographic patterns of the endemic frog species Nanorana pleskei across its known range in the eastern Tibetan Plateau, and conducted species distribution modelling (SDM) to explore changes of its distribution range through current and paleo periods. In all data sets, the species was divided into lineage north occupying open plateau platform and lineage south colonizing the mountainous plateau. The divergence of two major clades was estimated at the early Pleistocene. In mtDNA, lineage north contained northeastern and northwestern sublineages, and lineage south had two overlapping-distributed sublineages. Different lineages possessed distinct demographic characteristics, i.e., subdivision in the northeastern sublineage, historical bottleneck effects and recent expansions in the northwestern sublineage and the southeastern sublineage. SDMs depicted that stable suitable habitats had existed in the upper-middle streams of the Yellow River, Dadu River, Jinsha River and Yalong River. These regions were also recognized as the ancestral areas of different lineages. In conclusion, Nanorana pleskei lineages have probably experienced long-term separations. Stable suitable habitats existing in upper-middle streams of major rivers on the eastern Tibetan Plateau and distinct demographic dynamics of different lineages indicated that the lineages possessed independent evolutionary processes in multiple glacial refugia. The findings verified the profound effects of Pleistocene climatic fluctuations on the plateau endemic species.

  11. [Soil particle size distribution and its fractal dimension among degradation sequences of the alpine meadow in the source region of the Yangtze and Yellow River, Qinghai-Tibetan Plateau, China].

    Science.gov (United States)

    Wei, Mao-Hong; Lin, Hui-Long

    2014-03-01

    The alpine meadow in the source region of the Yangtze and Yellow River is suffering serious deterioration. Though great efforts have been put into, the restoration for the degraded grassland is far from being effective, mainly due to poor understanding of the degradation mechanism of alpine meadow in this region. In order to clarify the formation mechanism of degradation grassland and provide the new ideas for restoration, degradation sequences of the alpine meadow in the source region of the Yangtze and Yellow River were taken as target systems to analyze the soil particle size distribution, the fractal dimension of the soil particle size, and the relationship between soil erosion modulus and fractal dimension. The results showed that, with increasing grassland degradation, the percentage contents of clay increased while the percentage contents of silt sand and very fine sand showed a decreasing trend. The fractal dimension presented a positive correlation with clay among the degradation sequences while negative correlations were found with very fine sand and silt sand. The curvilinear regression of fractal dimension and erosion modulus fitted a quadratic function. Judged by the function, fractal dimension 2.81 was the threshold value of soil erosion. The threshold value has an indicative meaning on predicting the breakout of grazing-induced erosion and on restoration of the degraded grassland. Taking fractal dimension of 2.81 as the restoration indicator, adoption of corresponding measures to make fractal dimension less than 2.81, would an effective way to restore the degradation grassland.

  12. Cyprininae phylogeny revealed independent origins of the Tibetan Plateau endemic polyploid cyprinids and their diversifications related to the Neogene uplift of the plateau.

    Science.gov (United States)

    Wang, Xuzhen; Gan, Xiaoni; Li, Junbing; Chen, Yiyu; He, Shunping

    2016-11-01

    Origin and diversification of the Tibetan polyploid cyprinids (schizothoracins) may help us to explore relationships between diversification of the cyprinids and the Tibetan Plateau uplift. Cyprininae phylogeny was analyzed using mitochondrial and nuclear DNA sequences to trace origins of polyploidy and diversifications of schizothoracins. Ancestral states reconstruction for ploidy levels indicated that the Cyprininae was diploid origin and the schizothoracin clades tetraploid origins. There were two diversification rate shifts along with diversification of the cyprinine fishes in response to the Tibetan uplift. The unusual diversification shifts were located to branches subtending the clades of Tibetan polyploid cyprinids. Our analyses suggested that (i) phylogeny of Cyprininae recovered two independent origins of the Tibetan polyploidy schizothoracins; (ii) diversifications of the schizothoracins were closely related to the Neogene uplift of the Tibetan plateau in the following ways: the relatively ancient Late Oligocene-Middle Miocene adaptive radiation may be associated with the uplift of the southern Tibet and Himalaya; the Middle Miocene-Early Pleistocene lineage-specific diversification broadly coincident with major phase of the Neogene Tibetan uplift; and the most recent Pleistocene diversification shift in Schizothorax closely coincident with the successive Kunlun-Huanghe and Gonghe movements of the Tibetan uplift and the glaciation-induced climate oscillations on the plateau.

  13. A canine purgation study and risk factor analysis for echinococcosis in a high endemic region of the Tibetan plateau.

    NARCIS (Netherlands)

    Budke, C.M.; Campos Ponce, M.; Qian, B.F.; Torgerson, P.R.

    2005-01-01

    The Tibetan plateau of western China has been shown to have a very high prevalence of human cystic echinococcosis (CE) caused by Echinococcus granulosus and human alveolar echinococcosis (AE) caused by Echinococcus multilocularis. The domestic dog is suspected to be the primary definitive host for

  14. Ecophysiological responses to the effect of annual management on an endemic viviparous fish in central plateau of Mexico

    Directory of Open Access Journals (Sweden)

    Fernando Garcia-Trejo

    Full Text Available Studies on the biological aspects of fish typically focus on species that currently have commercial value, causing species that lack such market value to be ignored. This is the case of several freshwater fish, specifically of several members of the Goodeidae family. In the State of Querétaro there are several species of this family characterized for being viviparous and having distinctive sexual dimorphism that may have commercial potential. The subject of this study is Girardinichthys multiradiatus, a viviparous fish endemic to the upper-half of the Lerma River basin. The lack of knowledge regarding its biology and ecology has prevented the development of guidelines to manage its habitat and to preserve its population. The objective was to determine the ecophysiological responses of G. multiradiatus to its environmental management. From the sampling (24 hours every two months population structure and dynamics were analyzed throughout a hydrological cycle using meristic data (standard length. Trophic and ecophysiological responses to fluctuations in environmental factors were also identified. Although the mexcalpique is a polytrophic species, results show that it prefers feeding on Diptera or Cladocera, while detritus is the third substance frequently found in their stomachs. Environmentally, the water regime is responsible for fluctuations in the population dynamics of the species, while temperature changes are the most influence its energy balance. These results can guide efforts to conserve this species and its habitat.

  15. Ecophysiological Responses of Three Tree Species to a High-Altitude Environment in the Southeastern Tibetan Plateau

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    Jirui Gong

    2018-01-01

    Full Text Available This paper measured the ecophysiological responses of Populus cathayana Rehd., Salix longistamina C. Wang et P. Y. Fu., and Ulmus pumila L. to high altitude in the Tibetan Plateau based on changes in water relations, gas exchange, and chlorophyll fluorescence. P. cathayana and U. pumila have higher survival rates than S. longistamina, but the latter has highest biomass. S. longistamina has higher water-use efficiency (WUE, lower transpiration rates (E, higher water potential (Ψ, highest light saturation point (LSP and higher photosystem II (PSII photochemistry efficiency (Fv’/Fm’ and non-photochemistry quenching (NPQ than the other species, and is thus adapted to its habitat for afforestation. U. pumila has lower E, light compensation point (LCP, dark respiration (Rd, Fv’/Fm’ and electron transport rate (ETR, with higher Ψ, apparent quantum yield (AQY, net photosynthetic rate (Pn and non-photochemical quenching (NPQ, which helps it maintain water balance and utilize weak light to survive at high altitude. Relative low WUE, Ψ, Rd, NPQ, with high E, Pn, Fv’/Fm’ and biomass, imply that P. cathayana is more suitable for shelterbelt forests than for a semi-arid habitat. These three species can adapt to high-altitude conditions by different physiological mechanisms and morphological characteristics, which can provide a theoretical basis for afforestation and forest management in the Qinghai Tibetan Plateau.

  16. Relict Mountain Permafrost Area (Loess Plateau, China) Exhibits High Ecosystem Respiration Rates and Accelerating Rates in Response to Warming

    Science.gov (United States)

    Mu, Cuicui; Wu, Xiaodong; Zhao, Qian; Smoak, Joseph M.; Yang, Yulong; Hu, Lian; Zhong, Wen; Liu, Guimin; Xu, Haiyan; Zhang, Tingjun

    2017-10-01

    Relict permafrost regions are characterized by thin permafrost and relatively high temperatures. Understanding the ecosystem respiration rate (ERR) and its relationship with soil hydrothermal conditions in these areas can provide knowledge regarding the permafrost carbon cycle in a warming world. In this study, we examined a permafrost area, a boundary area, and a seasonally frozen ground area within a relict permafrost region on the east edge of the Qinghai-Tibetan Plateau, China. Measurements from July 2015 to September 2016 showed that the mean annual ecosystem CO2 emissions for the boundary area were greater than the permafrost area. The Q10 value of the ERRs in the seasonally frozen ground area was greater than the permafrost area, indicating that the carbon emissions in the nonpermafrost areas were more sensitive to warming. The 1 year open-top chamber (OTC) warming increased soil temperatures in both the permafrost and seasonally frozen ground areas throughout the year, and the warming increased the ERRs by 1.18 (0.99-1.38, with interquartile range) and 1.13 (0.75-1.54, with interquartile range) μmol CO2 m-2 s-1 in permafrost and seasonally frozen ground areas, respectively. The OTC warming increased annual ERRs by approximately 50% for both permafrost and seasonally frozen ground areas with half the increase occurring during the nongrowing seasons. These results suggest that the ERRs in relict permafrost are high in comparison with arctic regions, and the carbon balance in relict permafrost areas could be greatly changed by climate warming.

  17. [The epidemiology and etiology research of Tibetan sheep plague in Qinghai plateau].

    Science.gov (United States)

    Wei, Baiqing; Xiong, Haoming; Yang, Xiaoyan; Yang, Yonghai; Qi, Meiying; Jin, Juan; Xin, Youquan; Li, Xiang; Yang, Hanqing; Han, Xiumin; Dai, Ruixia

    2015-03-01

    To identify the epidemiology and etiology characteristics of Tibetan sheep plague in Qinghai plateau. The background materials of Qinghai Tibetan sheep plague found during 1975 to 2009 were summarized, the regional, time and interpersonal distribution, infection routes, ecological factors for the spread were used to analyze; followed by choosing 14 Yersinia pestis strains isolated from such sheep for biochemical test, toxicity test, virulence factors identification, plasmid analysis, and DFR genotype. From 1975 to 2009, 14 Yersinia pestis strains were isolated from Tibetan sheep in Qinghai province. Tibetan sheep, as the infection source, had caused 10 cases of human plague, 25 plague patients, and 13 cases of death. All of the initial cases were infected due to eating Tibetan sheep died of plague; followed by cases due to contact of plague patients, while all the initial cases were bubonic plague. Cases of bubonic plague developed into secondary pneumonic plague and septicemia plague were most popular and with high mortality. Most of the Tibetan sheep plague and human plague occurred in Gannan ecological zone in southern Gansu province, which was closely related to its unique ecological and geographical landscape. Tibetan sheep plague coincided with human plague caused by Tibetan sheep, especially noteworthy was that November (a time for marmots to start their dormancy) witnesses the number of Yersinia pestis strains isolated from Tibetan sheep and human plague cases caused by Tibetan sheep. This constituted the underlying cause that the epidemic time of Tibetan sheep plague lags obviously behind that of the Marmot plague. It was confirmed in the study that all the 14 strains were of Qinghai-Tibet Plateau ecotype, with virulence factors evaluation and toxicity test demonstrating strains as velogenic. As found in the (Different Region) DFR genotyping, the strains isolated from Yushu county and Zhiduo county were genomovar 5, the two strain isolated from Nangqian

  18. Land-use intensification can exaggerate the reduction of functionality with increasing soil biodiversity loss in an alpine meadow on eastern Tibetan Plateau

    Science.gov (United States)

    Liu, Manqiang; Chen, Xiaoyun; Chen, Chenying; Hu, Zhengkun; Guo, Hui; Li, Junyong; Du, Guozhen; Li, Huixin; Hu, Feng

    2017-04-01

    Soil biota plays a pivotal role in ecosystem functionality which is of central importance to sustainable services such as food and fiber production. Intensive land use is associated with species loss and subsequent the related functionality loss. Currently, the claim that negligible effects of soil biodiversity loss due to high functional redundancy has been questioned in the face of intense human activities. Recent studies corroborated that soil biodiversity guaranteed functionality following perturbation. Few studies have, however, attempted to explore the intensive land use on the relationship between soil biodiversity and function particularly for the region susceptible to human perturbation and climate change. With increasing demands for livestock on the Qinghai-Tibetan Plateau, extensive fertilization is a common way to fill the gap of grass productivity in the alpine meadow. However, excess chemical fertilizer can lead to the species loss and functionality degradation. Do the fertilizer-induced changes in soil biota lead to a higher risk of functionality? We predicted that fertilization would exacerbate effects of biodiversity-loss on the reduction of functionality. Herein, a dilution-to-extinction approach was used to set up soil biodiversity loss by inoculating serially diluted soil suspension (ranging from 100 to 10-8 levels) from two long-term fertilization treatments to the sterilized soil that has never been fertilized. The two fertilization treatments represented two distinct intensification land use including the unfertilized control (NP0) and a fertilized treatment (NP120) amended with (NH4)2HPO4 annually (120 kg ha-1 yr-1) since 2002 in an alpine meadow on the eastern Qinghai-Tibetan Plateau. Soil microcosms of 2 fertilization levels crossing 8 biodiversity levels were incubated for 8 months. Then, soil community and multi-functionality parameters including carbon (C)and nutrient mineralization, plant growth and functional stability were determined

  19. Functional evolution of leptin of Ochotona curzoniae in adaptive thermogenesis driven by cold environmental stress.

    Directory of Open Access Journals (Sweden)

    Jie Yang

    Full Text Available BACKGROUND: Environmental stress can accelerate the directional selection and evolutionary rate of specific stress-response proteins to bring about new or altered functions, enhancing an organism's fitness to challenging environments. Plateau pika (Ochotona curzoniae, an endemic and keystone species on Qinghai-Tibetan Plateau, is a high hypoxia and low temperature tolerant mammal with high resting metabolic rate and non-shivering thermogenesis to cope in this harsh plateau environment. Leptin is a key hormone related to how these animals regulate energy homeostasis. Previous molecular evolutionary analysis helped to generate the hypothesis that adaptive evolution of plateau pika leptin may be driven by cold stress. METHODOLOGY/PRINCIPAL FINDINGS: To test the hypothesis, recombinant pika leptin was first purified. The thermogenic characteristics of C57BL/6J mice injected with pika leptin under warm (23±1°C and cold (5±1°C acclimation is investigated. Expression levels of genes regulating adaptive thermogenesis in brown adipose tissue and the hypothalamus are compared between pika leptin and human leptin treatment, suggesting that pika leptin has adaptively and functionally evolved. Our results show that pika leptin regulates energy homeostasis via reduced food intake and increased energy expenditure under both warm and cold conditions. Compared with human leptin, pika leptin demonstrates a superior induced capacity for adaptive thermogenesis, which is reflected in a more enhanced β-oxidation, mitochondrial biogenesis and heat production. Moreover, leptin treatment combined with cold stimulation has a significant synergistic effect on adaptive thermogenesis, more so than is observed with a single cold exposure or single leptin treatment. CONCLUSIONS/SIGNIFICANCE: These findings support the hypothesis that cold stress has driven the functional evolution of plateau pika leptin as an ecological adaptation to the Qinghai-Tibetan Plateau.

  20. Freshwater Biogeography and Limnological Evolution of the Tibetan Plateau - Insights from a Plateau-Wide Distributed Gastropod Taxon (Radix spp.)

    Science.gov (United States)

    von Oheimb, Parm Viktor; Albrecht, Christian; Riedel, Frank; Du, Lina; Yang, Junxing; Aldridge, David C.; Bößneck, Ulrich; Zhang, Hucai; Wilke, Thomas

    2011-01-01

    Background The Tibetan Plateau is not only the highest and largest plateau on earth; it is also home to numerous freshwater lakes potentially harbouring endemic faunal elements. As it remains largely unknown whether these lakes have continuously existed during the Last Glacial Maximum (LGM), questions arise as to whether taxa have been able to exist on the plateau since before the latest Pleistocene, from where and how often the plateau was colonized, and by which mechanisms organisms conquered remote high altitude lentic freshwater systems. In this study, species of the plateau-wide distributed freshwater gastropod genus Radix are used to answer these biogeographical questions. Methodology/Principal Findings Based on a broad spatial sampling of Radix spp. on the Tibetan Plateau, and phylogenetic analyses of mtDNA sequence data, three probably endemic and one widespread major Radix clade could be identified on the plateau. Two of the endemic clades show a remarkably high genetic diversity, indicating a relatively great phylogenetic age. Phylogeographical analyses of individuals belonging to the most widely distributed clade indicate that intra-plateau distribution cannot be explained by drainage-related dispersal alone. Conclusions/Significance Our study reveals that Radix spp. persisted throughout the LGM on the Tibetan Plateau. Therefore, we assume the continuous existence of suitable water bodies during that time. The extant Radix diversity on the plateau might have been caused by multiple colonization events combined with a relatively long intra-plateau evolution. At least one colonization event has a Palaearctic origin. In contrast to freshwater fishes, passive dispersal, probably by water birds, might be an important mechanism for conquering remote areas on the plateau. Patterns found in Radix spp. are shared with some terrestrial plateau taxa, indicating that Radix may be a suitable model taxon for inferring general patterns of biotic origin, dispersal and

  1. Development of Three PCR Assays for the Differentiation between Echinococcus shiquicus, E. granulosus (G1 genotype), and E. multilocularis DNA in the Co-Endemic Region of Qinghai-Tibet plateau, China

    Science.gov (United States)

    Boufana, Belgees; Umhang, Gérald; Qiu, Jiamin; Chen, Xingwang; Lahmar, Samia; Boué, Franck; Jenkins, David; Craig, Philip

    2013-01-01

    To investigate echinococcosis in co-endemic regions, three polymerase chain reaction (PCR) assays based on the amplification of a fragment within the NADH dehydrogenase subunit 1 (ND1) mitochondrial gene were optimized for the detection of Echinococcus shiquicus, Echinococcus granulosus G1, and Echinococcus multilocularis DNA derived from parasite tissue or canid fecal samples. Specificity using parasite tissue-derived DNA was found to be 100% except for E. shiquicus primers that faintly detected E. equinus DNA. Sensitivity of the three assays for DNA detection was between 2 and 10 pg. Ethanol precipitation of negative PCR fecal samples was used to eliminate false negatives and served to increase sensitivity as exemplified by an increase in detection from 0% to 89% of E. shiquicus coproDNA using necropsy-positive fox samples. PMID:23438764

  2. Effects of animal's rumen juice on seed germination of Vicia ...

    African Journals Online (AJOL)

    To help understand the effects of grazing on seed germination characteristics of Vicia angustifolia L., we conducted a laboratory germination experiment of V. angustifolia L., which is a main companion species of Leguminosae family in alpine grassland of the Qinghai-Tibetan Plateau, using Yak and Tibetan sheep rumen ...

  3. Himalayan uplift shaped biomes in Miocene temperate Asia: evidence from leguminous Caragana

    Science.gov (United States)

    Ming-Li Zhang; Xiao-Guo Xiang; Juan-Juan Xue; Stewart C. Sanderson; Peter W. Fritsch

    2016-01-01

    Caragana, with distinctive variation in leaf and rachis characters, exhibits three centers of geographic distribution, i.e., Central Asia, the Qinghai-Tibetan Plateau (QTP), and East Asia, corresponding to distinct biomes. Because Caragana species are often ecologically dominant components of the vegetation in these regions, it is regarded as a key taxon for...

  4. Effects of mowing utilization on forage yield and quality in five oat ...

    African Journals Online (AJOL)

    Oat (Avena sativa) is grown to provide feed in winter for livestock production in the alpine area of Qinghai-Tibetan Plateau. The effect of early cutting (T1), late cutting (T2) as well as once cutting and twice cutting (T3) on forage yields and qualities were investigated for five oat varieties (YTA, CNC, B3, Q473 and Q444).

  5. Tibial Plateau Fractures

    DEFF Research Database (Denmark)

    Elsøe, Rasmus

    This PhD thesis reported an incidence of tibial plateau fractures of 10.3/100,000/year in a complete Danish regional population. The results reported that patients treated for a lateral tibial plateau fracture with bone tamp reduction and percutaneous screw fixation achieved a satisfactory level...... with only the subgroup Sport significantly below the age matched reference population. The thesis reports a level of health related quality of life (Eq5d) and disability (KOOS) significantly below established reference populations for patients with bicondylar tibial plateau fracture treated with a ring...... fixator, both during treatment and at 19 months following injury. In general, the thesis demonstrates that the treatment of tibial plateau fractures are challenging and that some disabilities following these fractures must be expected. Moreover, the need for further research in the area, both with regard...

  6. CENTRAL PLATEAU REMEDIATION

    International Nuclear Information System (INIS)

    ROMINE, L.D.

    2006-01-01

    A systematic approach to closure planning is being implemented at the Hanford Site's Central Plateau to help achieve the goal of closure by the year 2035. The overall objective of Central Plateau remediation is to protect human health and the environment from the significant quantity of contaminated material that resulted from decades of plutonium production in support of the nation's defense. This goal will be achieved either by removing contaminants or placing the residual contaminated materials in a secure configuration that minimizes further migration to the groundwater and reduces the potential for inadvertent intrusion into contaminated sites. The approach to Central Plateau cleanup used three key concepts--closure zones, closure elements, and closure process steps--to create an organized picture of actions required to complete remediation. These actions were merged with logic ties, constraints, and required resources to produce an integrated time-phased schedule and cost profile for Central Plateau closure. Programmatic risks associated with implementation of Central Plateau closure were identified and analyzed. Actions to mitigate the most significant risks are underway while high priority remediation projects continue to make progress

  7. An avifaunal case study of a plateau from Goa, India: an eye opener for conservation of plateau ecosystems

    Directory of Open Access Journals (Sweden)

    Minal Desai

    2012-03-01

    Full Text Available The lateritic plateaux typical of the midlands between the Western Ghats and the coastal plains of the Arabian Sea are known to be a unique ecosystem with a sizeable endemic flora. However, there is a total lack of studies on the faunal diversity of these plateaux, which are currently experiencing enormous anthropogenic pressures. We conducted a year-long study on the avifauna of the Taleigao Plateau, Goa. The Taleigao Plateau harbours 114 species of birds, accounting for 37% of the avifaunal diversity of the state. The resident bird population did not vary significantly through the seasons. Among the migrant birds, Rosy Starling Sturnus roseus was particularly partial to the plateau. Besides, five species of larks, grassland specialists were also recorded on the plateau. However, the absence of forest birds like the Malabar Pied Hornbill and the Indian Grey Hornbill (recorded earlier and the predominance of habitat generalists like the House Crow and the Jungle Myna seemed to be the offshoot of heavy anthropogenic pressures on the plateau. It is recommended that at least some plateaux in the belt deserve to be protected from the impact of unsustainable developmental process

  8. Browse Title Index

    African Journals Online (AJOL)

    Items 4251 - 4300 of 11090 ... Vol 9, No 4 (2010), Effects of mowing utilization on forage yield and quality in five oat varieties in alpine area of the eastern Qinghai-Tibetan Plateau, Abstract PDF. W Gao-Lin, W Mei-Ru, G Ting, H Tian-Ming, G Davidson. Vol 7, No 17 (2008), Effects of municipal sewage sludge doses on the yield, ...

  9. Whole-Genome Sequence of Chlamydia abortus Strain GN6 Isolated from Aborted Yak Fetus

    OpenAIRE

    Li, Zhaocai; Cai, Jinshan; Cao, Xiaoan; Lou, Zhongzi; Chao, Yilin; Kan, Wei; Zhou, Jizhang

    2017-01-01

    ABSTRACT The obligate intracellular Gram-negative bacterium Chlamydia abortus is one of the causative agents of abortion and fetal loss in sheep, goats, and cattle in many countries. It also affects the reproductivity of yaks (Bos grunniens). This study reports the whole-genome sequence of Chlamydia abortus strain GN6, which was isolated from aborted yak fetus in Qinghai-Tibetan Plateau, China.

  10. Whole-Genome Sequence of Chlamydia abortus Strain GN6 Isolated from Aborted Yak Fetus.

    Science.gov (United States)

    Li, Zhaocai; Cai, Jinshan; Cao, Xiaoan; Lou, Zhongzi; Chao, Yilin; Kan, Wei; Zhou, Jizhang

    2017-08-31

    The obligate intracellular Gram-negative bacterium Chlamydia abortus is one of the causative agents of abortion and fetal loss in sheep, goats, and cattle in many countries. It also affects the reproductivity of yaks ( Bos grunniens ). This study reports the whole-genome sequence of Chlamydia abortus strain GN6, which was isolated from aborted yak fetus in Qinghai-Tibetan Plateau, China. Copyright © 2017 Li et al.

  11. The medicinal plants of Frangensko Plateau (Northeastern Bulgaria)

    Science.gov (United States)

    Zahariev, Dimcho; Kacheva, Cvetelina

    2015-12-01

    The Frangensko Plateau is located in the northeastern part of Bulgaria and covers an area of 360 km2. On the territory of the plateau there are two protected areas, as well as two areas of the European ecological network NATURA 2000. The study of the medicinal plants on the territory of the Frangensko Plateau is made for the first time. As a result of our research we found 362 species of vascular plants from 242 genera and 80 families. The most of the families and the genera are represented by a small number of inferior taxa. The analysis of their life form indicates that the hemicryptophytes dominate with 39.50%, followed by the phanerophytes (22.10%). The biological types are represented mainly by perennial herbaceous plants (52.21%), annual herbaceous plants (14.09%) and trees (10.50%). There are 8 types of floristic elements divided in 32 groups. The largest percentage of species is of European type (51.93%). Among the medicinal plants, there are two Balkan endemic species, one Bulgarian endemic species and 30 relic species. Thirty four species with protection statute are described. The anthropophytes among the medicinal plants are 242 species (66.85%).

  12. The vascular flora of the Tepoš plateau around Pirot city (Eastern Serbia

    Directory of Open Access Journals (Sweden)

    Jotić, B.

    2013-12-01

    Full Text Available The flora of the karst plateau Tepoš, which is the part of Vidlič mountain (eastern Serbia was studied. Based on the analysis of the collected material and data from the literature, it was noted that the flora of Tepoš plateau is represented by 486 species, distributed in 284 genera and 68 families of vascular plants. The biological spectra was shown. The hemicriptophytic-terophytic character was established by analyzing the presence of plant life forms. By phytogeographical analysis the presence of 25 area types was established. The euroasian florystic chorion with 258 species of eurasian area type is the most abundant, followed by mediterranean-submediterranean (58 species, central-european (47 species, cosmopolitan (27 species and pontian area type (24 species. In the flora of Tepoš plateau the 9 balkan endemic taxa were recorded, which is 3,14% of total balkan endemic taxa in flora of Serbia. A small number of endemic taxa is expected, considering the low diversity of habitats. Balkan endemic taxa recorded in this area are: Acer hyrcanum subsp. intermedium, Bupleurum flavicans, Crucianella graeca, Eryngium palmatum, Pastinaca hirsuta, Hypericum rumeliacum subsp. rumeliacum, Thymus praecox subsp. jankae, Linaria rubioides subsp. nissana and Viola tricolor subsp. macedonica.

  13. Uplift-driven diversification in the Hengduan Mountains, a temperate biodiversity hotspot.

    Science.gov (United States)

    Xing, Yaowu; Ree, Richard H

    2017-04-25

    A common hypothesis for the rich biodiversity found in mountains is uplift-driven diversification-that orogeny creates conditions favoring rapid in situ speciation of resident lineages. We tested this hypothesis in the context of the Qinghai-Tibetan Plateau (QTP) and adjoining mountain ranges, using the phylogenetic and geographic histories of multiple groups of plants to infer the tempo (rate) and mode (colonization versus in situ diversification) of biotic assembly through time and across regions. We focused on the Hengduan Mountains region, which in comparison with the QTP and Himalayas was uplifted more recently (since the late Miocene) and is smaller in area and richer in species. Time-calibrated phylogenetic analyses show that about 8 million y ago the rate of in situ diversification increased in the Hengduan Mountains, significantly exceeding that in the geologically older QTP and Himalayas. By contrast, in the QTP and Himalayas during the same period the rate of in situ diversification remained relatively flat, with colonization dominating lineage accumulation. The Hengduan Mountains flora was thus assembled disproportionately by recent in situ diversification, temporally congruent with independent estimates of orogeny. This study shows quantitative evidence for uplift-driven diversification in this region, and more generally, tests the hypothesis by comparing the rate and mode of biotic assembly jointly across time and space. It thus complements the more prevalent method of examining endemic radiations individually and could be used as a template to augment such studies in other biodiversity hotspots.

  14. Into Tibet: An Early Pliocene Dispersal of Fossil Zokor (Rodentia: Spalacidae) from Mongolian Plateau to the Hinterland of Tibetan Plateau.

    Science.gov (United States)

    Li, Qiang; Wang, Xiaoming

    2015-01-01

    This paper reports the fossil zokors (Myospalacinae) collected from the lower Pliocene (~4.4 Ma) of Zanda Basin, southwestern Tibet, which is the first record in the hinterland of Tibetan Plateau within the Himalayan Range. Materials include 29 isolated molars belonging to Prosiphneus eriksoni (Schlosser, 1924) by having characters including large size, highly fused roots, upper molars of orthomegodont type, m1 anterior cap small and centrally located, and first pair of m1 reentrants on opposing sides, high crowns, and high value of dentine tract parameters. Based on the cladistics analysis, all seven species of Prosiphneus and P. eriksoni of Zanda form a monophyletic clade. P. eriksoni from Zanda, on the other hand, is nearly the terminal taxon of this clade. The appearance of P. eriksoni in Zanda represents a significant dispersal in the early Pliocene from its center of origin in north China and Mongolian Plateau, possibly via the Hol Xil-Qiangtang hinterland in northern Tibet. The fast evolving zokors are highly adapted to open terrains at a time when regional climates had become increasingly drier in the desert zones north of Tibetan Plateau during the late Miocene to Pliocene. The occurrence of this zokor in Tibet thus suggests a rather open steppe environment. Based on fossils of large mammals, we have formulated an "out of Tibet" hypothesis that suggests earlier and more primitive large mammals from the Pliocene of Tibet giving rise to the Ice Age megafauna. However, fossil records for large mammals are still too poor to evaluate whether they have evolved from lineages endemic to the Tibetan Plateau or were immigrants from outside. The superior record of small mammals is in a better position to address this question. With relatively dense age intervals and numerous localities in much of northern Asia, fossil zokors provide the first example of an "into Tibet" scenario--earlier and more primitive taxa originated from outside of the Tibetan Plateau and the

  15. Phylogeography of Pinus armandii and its relatives: heterogeneous contributions of geography and climate changes to the genetic differentiation and diversification of Chinese white pines.

    Directory of Open Access Journals (Sweden)

    Liu Liu

    Full Text Available Geographic barriers and Quaternary climate changes are two major forces driving the evolution, speciation, and genetic structuring of extant organisms. In this study, we used Pinus armandii and eleven other Asian white pines (subsection Strobus, subgenus Pinus to explore the influences of geographic factors and Pleistocene climatic oscillations on species in South China, a region known to be centers of plant endemism and biodiversity hotspots. Range-wide patterns of genetic variation were investigated using chloroplast and mitochondrial DNA markers, with extensive sampling throughout the entire range of P. armandii. Both cpDNA and mtDNA revealed that P. armandii exhibits high levels of genetic diversity and significant population differentiation. Three geographically distinct subdivisions corresponding to the Qinling-Daba Mountains (QDM, Himalaya-Hengduan Mountains (HHM and Yungui Plateau (YGP were revealed in mainland China by cpDNA. Their break zone was located in the southeastern margin of the Qinghai-Tibetan Plateau (QTP. A series of massive mountains, induced by the QTP uplift, imposed significant geographic barriers to genetic exchange. The disjunct distribution patterns of ancestral haplotypes suggest that a large continuous population of the white pines may have existed from southwest to subtropical China. Repeated range shifts in response to the Pleistocene glaciations led to the isolation and diversification of the subtropical species. The two Taiwanese white pines share a common ancestor with the species in mainland China and obtain their chloroplasts via long-distance pollen dispersal from North Asian pines. Distinct genetic patterns were detected in populations from the Qinling-Daba Mountains, Yungui Plateau, Himalaya-Hengduan Mountains, and subtropical China, indicating significant contributions of geographic factors to the genetic differentiation in white pines. Our study depicts a clear picture of the evolutionary history of

  16. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    Energy Technology Data Exchange (ETDEWEB)

    BERGMAN, T. B.; STEFANSKI, L. D.; SEELEY, P. N.; ZINSLI, L. C.; CUSACK, L. J.

    2012-09-19

    THE CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY WAS CONDUCTED TO DEVELOP AN OPTIMAL SEQUENCE OF REMEDIATION ACTIVITIES IMPLEMENTING THE CERCLA DECISION ON THE CENTRAL PLATEAU. THE STUDY DEFINES A SEQUENCE OF ACTIVITIES THAT RESULT IN AN EFFECTIVE USE OF RESOURCES FROM A STRATEGIC PERSPECTIVE WHEN CONSIDERING EQUIPMENT PROCUREMENT AND STAGING, WORKFORCE MOBILIZATION/DEMOBILIZATION, WORKFORCE LEVELING, WORKFORCE SKILL-MIX, AND OTHER REMEDIATION/DISPOSITION PROJECT EXECUTION PARAMETERS.

  17. Greenland plateau jets

    Directory of Open Access Journals (Sweden)

    George William Kent Moore

    2013-08-01

    Full Text Available The high ice-covered topography of Greenland represents a significant barrier to atmospheric flow and, as a direct and indirect result, it plays a crucial role in the coupled climate system. The wind field over Greenland is important in diagnosing regional weather and climate, thereby providing information on the mass balance of the ice sheet as well as assisting in the interpretation of ice core data. Here, we identify a number of hitherto unrecognised features of the three-dimensional wind field over Greenland; including a 2500-km-long jet along the central ice sheet's western margin that extends from the surface into the middle-troposphere, as well as a similar but smaller scale and less intense feature along its eastern margin. We refer to these features as Greenland Plateau Jets. The jets are coupled to the downslope katabatic flow and we argue that they are maintained by the zonal temperature gradients associated with the strong temperature inversion over the central ice sheet. Their importance for Greenland's regional climate is discussed.

  18. The endemic flora of Greece

    DEFF Research Database (Denmark)

    Tan, Kit

    2007-01-01

    The Balkan Peninsula has a rich endemic flora estimated as between 2600 and 2700 taxa; c. 750 are restricted to Greece. Conservationists consider the endemic flora of a country needs protection for all time; there is a tendency to paint an alarming picture. However, unless one knows something or ...... have been mapped and it is already possible to recognize the hot-spots of biodiversity as these are linked to the centres of endemism. Determining the centres of diversity is an important and significant contribution to further conservation measures at the global level....

  19. Organizational restructuring and career plateauing

    NARCIS (Netherlands)

    P. Paffen; Hans Timmermans

    2009-01-01

    This article describes a flexibility program for plateaued professionals in a technical Dutch firm operating in the consultancy sector we will refer to with the pseudonym Greentree Corp. First, we will discuss the impact reorganization had on job-requirements and career opportunities for technical

  20. Mammal endemism In Italy: A review

    Directory of Open Access Journals (Sweden)

    Giovanni Amori

    2018-02-01

    Full Text Available Although there are various checklists of Italian mammals, there is not yet a synthesis of those mammals that are endemic to Italy. Therefore, we provide for the first time a detailed review on Italian mammal endemic species including endemic taxa deserving additional studies. This review is based on the most recent taxonomic revisions obtained using Scopus and Google Scholar databases. We also considered the age of endemic species. Some aspects of mammalian conservation are also provided and discussed.

  1. The Pajarito Plateau: A bibliography

    Science.gov (United States)

    Mathien, Frances Joan; Steen, Charlie R.; Allen, Craig D.

    1993-01-01

    This bibliography is the result of two initially independent projects. As the consulting archaeologist at Los Alamos National Laboratory (LANL), Charlie R. Steen collected entries at the suggestion of the staff of the Environmental Surveillance Group of the Health, Safety, and Environmental Division, HSE-8. The primary purpose was to aid the staff in evaluating cultural resources on LANL lands. In addition to works that related to the archaeology and history of the area, Steen included notations of a few books and articles in other fields such as geology and natural history. It was hoped that they also would be of value to other organizations and to students of past human activities on the Pajarito Plateau.At the same time, the National Park Service (NPS) was planning a major survey of Bandelier National Monument (BNM). As part of this plan, the author was asked to prepare a background document that described research previously carried out in the area, including an annotated bibliography. Although the survey would be limited to the park boundaries, the larger Pajarito Plateau is a more logical study area from physiographic, environmental, and cultural perspectives; hence the focus was on this larger region. Mathien (1986) also included some references to natural resources studies, particularly those initiated by NPS within Bandelier National Monument.Both bibliographies were made available to Colleen Olinger and Beverly Larson of the Health and Environmental Services Group at Los Alamos. They realized that while neither was complete, each included entries missing from the other. Larson suggested the two bibliographies be combined. (At this time, Craig Allen was studying the landscape of the Jemez Mountains [Allen 1984c, 1989]. His investigations included much detailed information on natural resource studies and were added in 1991 and 1992.)To limit the scope of their work, Steen and Mathien had chosen their parameter: the Pajarito Plateau. Geographically, the

  2. Endemic Images and the Desensitization Process.

    Science.gov (United States)

    Saigh, Philip A.; Antoun, Fouad T.

    1984-01-01

    Examined the effects of endemic images on levels of anxiety and achievement of 48 high school students. Results suggested that a combination of endemic images and study skills training was as effective as desensitization plus study skills training. Includes the endemic image questionnaire. (JAC)

  3. Monuments of the Giza Plateau

    Science.gov (United States)

    Ruggles, Clive L. N.

    The colossal pyramids of the pharaohs Khufu (Cheops), Khafre (Chephren), and Menkaure (Mycerinus) have attracted a huge amount of astronomical interest over the years, both scholarly and popular. Less attention is usually given to the broader context of structures on the Giza Plateau. One of the most notorious ideas connecting the Giza Plateau with astronomy is that the three large pyramids are laid out on the ground so as to reflect the appearance of the three stars of Orion's Belt in the sky. This idea is unsupportable for several reasons but has succeeded in generating huge public interest. Of much greater serious interest is the fact that the three main pyramids were oriented cardinally to extraordinary precision, which raises the questions of why this was important and how it was achieved. Another idea that has attracted serious attention but also some confusion is that the orientations of some narrow shafts within Khufu's pyramid might have been deliberately aligned upon particular stars. The overall layout of monuments on the plateau may certainly have been designed so as to emphasize certain solar phenomena, for symbolic and ideological reasons relating to a dominant sun cult. It is also possible that it formed part of a wider cosmological "master plan" extending to other pyramids and temples up to 20 km distant.

  4. Endemic Nephropathy Around the World.

    Science.gov (United States)

    Gifford, Fiona J; Gifford, Robert M; Eddleston, Michael; Dhaun, Neeraj

    2017-03-01

    There have been several global epidemics of chronic kidney disease of unknown etiology (CKD u ). Some, such as Itai-Itai disease in Japan and Balkan endemic nephropathy, have been explained, whereas the etiology of others remains unclear. In countries such as Sri Lanka, El Salvador, Nicaragua, and India, CKD u is a major public health problem and causes significant morbidity and mortality. Despite their geographical separation, however, there are striking similarities between these endemic nephropathies. Young male agricultural workers who perform strenuous labor in extreme conditions are the worst affected. Patients remain asymptomatic until end-stage renal failure. Biomarkers of tubular injury are raised, and kidney biopsy shows chronic interstitial nephritis with associated tubular atrophy. In many of these places access to dialysis and transplantation is limited, leaving few treatment options. In this review we briefly describe the major historic endemic nephropathies. We then summarize the epidemiology, clinical features, histology and clinical course of CKD u in Mesoamerica, Sri Lanka, India, Egypt, and Tunisia. We draw comparisons between the proposed etiologies and supporting research. Recognition of the similarities may reinforce the international drive to establish causality and to effect prevention.

  5. Endemic Nephropathy Around the World

    Directory of Open Access Journals (Sweden)

    Fiona J. Gifford

    2017-03-01

    Full Text Available There have been several global epidemics of chronic kidney disease of unknown etiology (CKDu. Some, such as Itai-Itai disease in Japan and Balkan endemic nephropathy, have been explained, whereas the etiology of others remains unclear. In countries such as Sri Lanka, El Salvador, Nicaragua, and India, CKDu is a major public health problem and causes significant morbidity and mortality. Despite their geographical separation, however, there are striking similarities between these endemic nephropathies. Young male agricultural workers who perform strenuous labor in extreme conditions are the worst affected. Patients remain asymptomatic until end-stage renal failure. Biomarkers of tubular injury are raised, and kidney biopsy shows chronic interstitial nephritis with associated tubular atrophy. In many of these places access to dialysis and transplantation is limited, leaving few treatment options. In this review we briefly describe the major historic endemic nephropathies. We then summarize the epidemiology, clinical features, histology and clinical course of CKDu in Mesoamerica, Sri Lanka, India, Egypt, and Tunisia. We draw comparisons between the proposed etiologies and supporting research. Recognition of the similarities may reinforce the international drive to establish causality and to effect prevention.

  6. PLATEAU IRIS SYNDROME--CASE SERIES.

    Science.gov (United States)

    Feraru, Crenguta Ioana; Pantalon, Anca Delia; Chiselita, Dorin; Branisteanu, Daniel

    2015-01-01

    Plateau iris is characterized by closing the anterior chamber angle due to a large ciliary body or due to its anterior insertion that alters the position of iris periphery in respect to the trabecular meshwork. There are two aspects that need to be differentiated: plateau iris configuration and plateau iris syndrome. The first describes a situation when the iris root is flat and the anterior chamber is not shallow, the latter refers to a post laser iridotomy condition in which a patent iridotomy has removed the relative pupillary block, but goniscopically confirmed angle closure recurs without central shallowing of the anterior chamber. Isolated plateau iris syndrome is rare compared to plateau iris configuration. We hereby present two case reports of plateau iris syndrome in young patients who came to an ophthalmologic consult by chance.

  7. Testing the effect of the Himalayan mountains as a physical barrier to gene flow in Hippophae tibetana Schlect. (Elaeagnaceae.

    Directory of Open Access Journals (Sweden)

    La Qiong

    Full Text Available Hippophae tibetana is a small, dioecious wind-pollinated shrub endemic to the Tibetan-Qinghai Plateau. It is one of the shrubs that occur at very high elevations (5250 m a.s.l.. The Himalayan mountains provides a significant geographical barrier to the Qinghai-Tibetan Plateau, dividing the Himalayan area into two regions with Nepal to the south and Tibet to the north. There is no information on how the Himalayan mountains influence gene flow and population differentiation of alpine plants. In this study, we analyzed eight nuclear microsatellite markers and cpDNA trnT-trnF regions to test the role of the Himalayan mountains as a barrier to gene flow between populations of H. tibetana. We also examined the fine-scale genetic structure within a population of H. tibetana on the north slope of Mount (Mt. Everest. For microsatellite analyses, a total of 241 individuals were sampled from seven populations in our study area (4 from Nepal, 3 from Tibet, including 121 individuals that were spatially mapped within a 100 m × 100 m plot. To test for seed flow, the cpDNA trnT-trnF regions of 100 individuals from 6 populations (4 from Nepal, 2 from Tibet were also sequenced. Significant genetic differentiation was detected between the two regions by both microsatellite and cpDNA data analyses. These two datasets agree about southern and northern population differentiation, indicating that the Himalayan mountains represent a barrier to H. tibetana limiting gene flow between these two areas. At a fine scale, spatial autocorrelation analysis suggests significant genetic structure within a distance of less than 45 m, which may be attributed mainly to vegetative reproduction and habitat fragmentation, as well as limited gene flow.

  8. Iceberg incursions across Campbell Plateau

    International Nuclear Information System (INIS)

    Northcote, L.; Neil, H.; Carter, L.

    1999-01-01

    The last reported sighting of icebergs off eastern New Zealand was on 28th October, 1892, at the Chatham Islands. Prior to that time, the SW Pacific Ocean periodically hosted flotillas of icebergs, as revealed by a palaeoceanographic analysis of 8 cores from the Campbell Plateau. Stable isotope stratigraphy, coupled with down-core measurements of magnetic susceptibility, grain size, calcium carbonate and ice-rafted debris, highlight climate-related fluctuations in iceberg activity back to at least marine isotope stage (MIS) 6 - our longest complete record. (author)

  9. PLATEAU IRIS – DIAGNOSIS AND TREATMENT

    Science.gov (United States)

    Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

    2015-01-01

    Objectives: The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Systematic review methodology: Relevant publications on plateau iris that were published until 2014. Conclusions: Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty PMID:27373109

  10. PLATEAU IRIS--DIAGNOSIS AND TREATMENT.

    Science.gov (United States)

    Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

    2015-01-01

    The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Relevant publications on plateau iris that were published until 2014. Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty.

  11. Two new species of Indigofera L. (Leguminosae) from the Sneeuberg Centre of Floristic Endemism, Great Escarpment (Eastern and Western Cape, South Africa).

    Science.gov (United States)

    Clark, V Ralph; Schrire, Brian D; Barker, Nigel P

    2015-01-01

    Two new species of Indigofera L. (Leguminosae) are described from the Sneeuberg Centre of Floristic Endemism on the southern Great Escarpment, Eastern and Western Cape Provinces, South Africa. Both species are localised high-altitude endemics. Indigoferamagnifica Schrire & V.R. Clark is confined to the summit plateau of the Toorberg-Koudeveldberg-Meelberg west of Graaff-Reinet, and complements other western Sneeuberg endemics such as Ericapasserinoides (Bolus) E.G.H. Oliv. and Faurearecondita Rourke & V.R. Clark. Indigoferaasantasanensis Schrire & V.R. Clark is confined to a small area east of Graaff-Reinet, and complements several other eastern Sneeuberg endemics such as Euryopsexsudans B. Nord & V.R. Clark and Euryopsproteoides B. Nord. & V.R. Clark. Based on morphology, both new species belong to the Cape Clade of Indigofera, supporting a biogeographical link between the Cape Floristic Region and the Sneeuberg, as well as with the rest of the eastern Great Escarpment.

  12. Phylogeography of Schizopygopsis stoliczkai (Cyprinidae) in Northwest Tibetan Plateau area.

    Science.gov (United States)

    Wanghe, Kunyuan; Tang, Yongtao; Tian, Fei; Feng, Chenguang; Zhang, Renyi; Li, Guogang; Liu, Sijia; Zhao, Kai

    2017-11-01

    Schizopygopsis stoliczkai (Cyprinidae, subfamily Schizothoracinae) is one of the major freshwater fishes endemic to the northwestern margin of the Tibetan Plateau. In the current study, we used mitochondrial DNA markers cytochrome b (Cyt b ) and 16S rRNA (16S), as well as the nuclear marker, the second intron of the nuclear beta-actin gene (Act2), to uncover the phylogeography of S. stoliczkai . In total, we obtained 74 haplotypes from 403 mitochondrial concatenated sequences. The mtDNA markers depict the phylogenetic structures of S. stoliczkai , which consist of clade North and clade South. The split time of the two clades is dated back to 4.27 Mya (95% HPD = 1.96-8.20 Mya). The estimated split time is earlier than the beginning of the ice age of Pleistocene (2.60 Mya), suggesting that the northwestern area of the Tibetan Plateau probably contain at least two glacial refugia for S. stoliczkai . SAMOVA supports the formation of four groups: (i) the Karakash River group; (ii) The Lake Pangong group; (iii) the Shiquan River group; (iv) the Southern Basin group. Clade North included Karakash River, Lake Pangong, and Shiquan River groups, while seven populations of clade South share the haplotypes. Genetic diversity, star-like network, BSP analysis, as well as negative neutrality tests indicate recent expansions events of S. stoliczkai . Conclusively, our results illustrate the phylogeography of S. stoliczkai , implying the Shiquan River is presumably the main refuge for S. stoliczkai .

  13. Phylogeographic patterns of the desert poplar in Northwest China shaped by both geology and climatic oscillations.

    Science.gov (United States)

    Zeng, Yan-Fei; Zhang, Jian-Guo; Abuduhamiti, Bawerjan; Wang, Wen-Ting; Jia, Zhi-Qing

    2018-05-25

    The effects of historical geology and climatic events on the evolution of plants around the Qinghai-Tibetan Plateau region have been at the center of debate for years. To identify the influence of the uplift of the Tianshan Mountains and/or climatic oscillations on the evolution of plants in arid northwest China, we investigated the phylogeography of the Euphrates poplar (Populus euphratica) using chloroplast DNA (cpDNA) sequences and nuclear microsatellites, and estimated its historical distribution using Ecological Niche Modeling (ENM). We found that the Euphrates poplar differed from another desert poplar, P. pruinosa, in both nuclear and chloroplast DNA. The low clonal diversity in both populations reflected the low regeneration rate by seed/seedlings in many locations. Both cpDNA and nuclear markers demonstrated a clear divergence between the Euphrates poplar populations from northern and southern Xinjiang regions. The divergence time was estimated to be early Pleistocene based on cpDNA, and late Pleistocene using an Approximate Bayesian Computation analysis based on microsatellites. Estimated gene flow was low between these two regions, and the limited gene flow occurred mainly via dispersal from eastern regions. ENM analysis supported a wider distribution of the Euphrates poplar at 3 Ma, but a more constricted distribution during both the glacial period and the interglacial period. These results indicate that the deformation of the Tianshan Mountains has impeded gene flow of the Euphrates poplar populations from northern and southern Xinjiang, and the distribution constriction due to climatic oscillations further accelerated the divergence of populations from these regions. To protect the desert poplars, more effort is needed to encourage seed germination and seedling establishment, and to conserve endemic gene resources in the northern Xinjiang region.

  14. Delimiting areas of endemism through kernel interpolation.

    Science.gov (United States)

    Oliveira, Ubirajara; Brescovit, Antonio D; Santos, Adalberto J

    2015-01-01

    We propose a new approach for identification of areas of endemism, the Geographical Interpolation of Endemism (GIE), based on kernel spatial interpolation. This method differs from others in being independent of grid cells. This new approach is based on estimating the overlap between the distribution of species through a kernel interpolation of centroids of species distribution and areas of influence defined from the distance between the centroid and the farthest point of occurrence of each species. We used this method to delimit areas of endemism of spiders from Brazil. To assess the effectiveness of GIE, we analyzed the same data using Parsimony Analysis of Endemism and NDM and compared the areas identified through each method. The analyses using GIE identified 101 areas of endemism of spiders in Brazil GIE demonstrated to be effective in identifying areas of endemism in multiple scales, with fuzzy edges and supported by more synendemic species than in the other methods. The areas of endemism identified with GIE were generally congruent with those identified for other taxonomic groups, suggesting that common processes can be responsible for the origin and maintenance of these biogeographic units.

  15. Delimiting areas of endemism through kernel interpolation.

    Directory of Open Access Journals (Sweden)

    Ubirajara Oliveira

    Full Text Available We propose a new approach for identification of areas of endemism, the Geographical Interpolation of Endemism (GIE, based on kernel spatial interpolation. This method differs from others in being independent of grid cells. This new approach is based on estimating the overlap between the distribution of species through a kernel interpolation of centroids of species distribution and areas of influence defined from the distance between the centroid and the farthest point of occurrence of each species. We used this method to delimit areas of endemism of spiders from Brazil. To assess the effectiveness of GIE, we analyzed the same data using Parsimony Analysis of Endemism and NDM and compared the areas identified through each method. The analyses using GIE identified 101 areas of endemism of spiders in Brazil GIE demonstrated to be effective in identifying areas of endemism in multiple scales, with fuzzy edges and supported by more synendemic species than in the other methods. The areas of endemism identified with GIE were generally congruent with those identified for other taxonomic groups, suggesting that common processes can be responsible for the origin and maintenance of these biogeographic units.

  16. Environmental Monitoring of Endemic Cholera

    Science.gov (United States)

    ElNemr, W.; Jutla, A. S.; Constantin de Magny, G.; Hasan, N. A.; Islam, M.; Sack, R.; Huq, A.; Hashem, F.; Colwell, R.

    2012-12-01

    Cholera remains a major public health threat. Since Vibrio cholerae, the causative agent of the disease, is autochthonous to riverine, estuarine, and coastal waters, it is unlikely the bacteria can be eradicated from its natural habitat. Prediction of disease, in conjunction with preventive vaccination can reduce the prevalence rate of a disease. Understanding the influence of environmental parameters on growth and proliferation of bacteria is an essential first step in developing prediction methods for outbreaks. Large scale geophysical variables, such as SST and coastal chlorophyll, are often associated with conditions favoring growth of V. cholerae. However, local environmental factors, meaning biological activity in ponds from where the bulk of populations in endemic regions derive water for daily usage, are either neglected or oversimplified. Using data collected from several sites in two geographically distinct locations in South Asia, we have identified critical local environmental factors associated with cholera outbreak. Of 18 environmental variables monitored for water sources in Mathbaria (a coastal site near the Bay of Bengal) and Bakergonj (an inland site) of Bangladesh, water depth and chlorophyll were found to be important factors associated with initiation of cholera outbreaks. Cholera in coastal regions appears to be related to intrusion. However, monsoonal flooding creates conditions for cholera epidemics in inland regions. This may be one of the first attempts to relate in-situ environmental observations with cholera. We anticipate that it will be useful for further development of prediction models in the resource constrained regions.

  17. Measuring Surface Deformation in Glacier Retreated Areas Based on Ps-Insar - Geladandong Glacier as a Case Study

    Science.gov (United States)

    Mohamadi, B.; Balz, T.

    2018-04-01

    Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF). In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

  18. Shifts in species interactions due to the evolution of functional differences between endemics and non-endemics: an endemic syndrome hypothesis.

    Directory of Open Access Journals (Sweden)

    Courtney E Gorman

    Full Text Available Species ranges have been shifting since the Pleistocene, whereby fragmentation, isolation, and the subsequent reduction in gene flow have resulted in local adaptation of novel genotypes and the repeated evolution of endemic species. While there is a wide body of literature focused on understanding endemic species, very few studies empirically test whether or not the evolution of endemics results in unique function or ecological differences relative to their widespread congeners; in particular while controlling for environmental variation. Using a common garden composed of 15 Eucalyptus species within the subgenus Symphyomyrtus (9 endemic to Tasmania, 6 non-endemic, here we hypothesize and show that endemic species are functionally and ecologically different from non-endemics. Compared to non-endemics, endemic Eucalyptus species have a unique suite of functional plant traits that have extended effects on herbivores. We found that while endemics occupy many diverse habitats, they share similar functional traits potentially resulting in an endemic syndrome of traits. This study provides one of the first empirical datasets analyzing the functional differences between endemics and non-endemics in a common garden setting, and establishes a foundation for additional studies of endemic/non-endemic dynamics that will be essential for understanding global biodiversity in the midst of rapid species extinctions and range shifts as a consequence of global change.

  19. Non-endemic cases of lymphatic filariasis.

    Science.gov (United States)

    Jones, Robert T

    2014-11-01

    Several cases of lymphatic filariasis (LF) have been reported in non-endemic countries due to travellers, military personnel and expatriates spending time in and returning from endemic areas, as well as immigrants coming from these regions. These cases are reviewed to assess the scale and context of non-endemic presentations and to consider the biological factors underlying their relative paucity. Cases reported in the English, French, Spanish and Portuguese literature during the last 30 years were examined through a search of the PubMed, ProMED-mail and TropNet resources. The literature research revealed 11 cases of lymphatic filariasis being reported in non-endemic areas. The extent of further infections in recent migrants to non-endemic countries was also revealed through the published literature. The life-cycle requirements of Wuchereria and Brugia species limit the extent of transmission of LF outside of tropical regions. However, until elimination, programmes are successful in managing the disease, there remains a possibility of low rates of infection being reported in non-endemic areas, and increased international travel can only contribute to this phenomenon. Physicians need to be aware of the signs and symptoms of lymphatic filariasis, and infection should be considered in the differential diagnosis of people with a relevant travel history. © 2014 John Wiley & Sons Ltd.

  20. Prehistoric human settling on the Tibetan Plateau

    Science.gov (United States)

    Chen, F.; Zhang, D.; Dong, G.; Xia, H.

    2017-12-01

    When and where did human first settle down on the Tibetan Plateau is under hot debate among archaeologist, anthropologists, geneticist and paleo-geographers. Based on systematic archaeological, chronological and archaeo-botanical studies of 53 sites in Northeastern Tibetan Plateau, we propose that agriculture facilitated human permanent settlement on the Tibetan Plateau initially since 5200 years ago below 2500 masl and since 3600 years ago up to around 4000 masl, possibly assisted by domesticated animals (Chen et al. 2015). By redating the age of hand- and footprints in Chusang site in Tibet, Meyer et al. (2017) argue that hunter-gatherers permanently occupied central Tibetan Plateau in early Holocene (before 7.4 ka) without the help of agriculture. Except for the possible problem of dating, however, the limited hand- and footprints could only indicate the presence of prehistoric hunter-gatherers on the remote central Tibetan Plateau in the early Holocene, unable to support the permanent inhabitation assertion (Zhang et al., 2017). To better understand how human spread to, settle on and adapt to the Tibetan Plateau, we are closely working together with anthropologists, archaeologists and geneticists to do system Paleolithic surveys, full excavations, and genetic analysis of ancient and modern human, animals and plants. Our preliminary study show that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in the Northeastern Tibetan Plateau (NETP). This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) with different adaptation strategies, including microlithic technology, millet and barley farming, and sheep herding and so on (Zhang et al., 2016). In addition, our new finds in Tibet indicate that there are probably more migration routes from southeast and southwest Tibetan Plateau in the late Pleistocene or

  1. Relationships between climate and growth of Gymnocypris selincuoensis in the Tibetan Plateau.

    Science.gov (United States)

    Tao, Juan; Chen, Yifeng; He, Dekui; Ding, Chengzhi

    2015-04-01

    The consequences of climate change are becoming increasingly evident in the Tibetan Plateau, represented by glaciers retreating and lakes expanding, but the biological response to climate change by plateau-lake ecosystems is poorly known. In this study, we applied dendrochronology methods to develop a growth index chronology with otolith increment widths of Selincuo naked carp (Gymnocypris selincuoensis), which is an endemic species in Lake Selincuo (4530 m), and investigated the relationships between fish growth and climate variables (regional and global) in the last three decades. A correlation analysis and principle component regression analysis between regional climate factors and the growth index chronology indicated that the growth of G. selincuoensis was significantly and positively correlated with length of the growing season and temperature-related variables, particularly during the growing season. Most of global climate variables, which are relevant to the Asian monsoon and the midlatitude westerlies, such as El Nino Southern Oscillation Index, the Arctic Oscillation, North Atlantic Oscillation, and North America Pattern, showed negative but not significant correlations with the annual growth of Selincuo naked carp. This may have resulted from the high elevation of the Tibetan Plateau and the high mountains surrounding this area. In comparison, the Pacific Decade Oscillation (PDO) negatively affected the growth of G. selincuoensis. The reason maybe that enhancement of the PDO can lead to cold conditions in this area. Taken together, the results indicate that the Tibetan Plateau fish has been affected by global climate change, particularly during the growing season, and global climate change likely has important effects on productivity of aquatic ecosystems in this area.

  2. The Hikurangi Plateau: Tectonic Ricochet and Accretion

    Science.gov (United States)

    Willis, David; Moresi, Louis; Betts, Peter; Whittaker, Joanne

    2015-04-01

    80 million years between interactions with different subduction systems provided time for the Hikurangi Plateau and Pacific Ocean lithosphere to cool, densify and strengthen. Neogene subduction of the Hikurangi Plateau occurring orthogonal to its Cretaceous predecessor, provides a unique opportunity to explore how changes to the physical properties of oceanic lithosphere affect subduction dynamics. We used Underworld to build mechanically consistent collision models to understand the dynamics of the two Hikurangi collisions. The Hikurangi Plateau is a ~112 Ma, 15km thick oceanic plateau that has been entrained by subduction zones immediately preceding the final break-up of Eastern Gondwana and currently within the active Hikurangi Margin. We explore why attempted subduction of the plateau has resulted in vastly different dynamics on two separate occasions. Slab break-off occured during the collision with Gondwana, currently there is apparent subduction of the plateau underneath New Zealand. At ~100Ma the young, hot Hikurangi Plateau, positively buoyant with respect to the underlying mantle, impacted a Gondwana Margin under rapid extension after the subduction of an mid-ocean ridge 10-15Ma earlier. Modelling of plateaus within young oceanic crust indicates that subduction of the thickened crust was unlikely to occur. Frontal accretion of the plateau and accompanying slab break-off is expected to have occured rapidly after its arrival. The weak, young slab was susceptible to lateral propagation of the ~1500 km window opened by the collision, and break-off would have progressed along the subduction zone inhibiting the "step-back" of the trench seen in older plates. Slab break-off coincided with a world-wide reorganisation of plate velocites, and orogenic collapse along the Gondwana margin characterised by rapid extension and thinning of the over-riding continental plate from ~60 to 30km. Following extension, Zealandia migrated to the NW until the Miocene allowing the

  3. Computed tomography of tibial plateau fractures

    International Nuclear Information System (INIS)

    Rafii, M.; Firooznia, H.; Golimbu, C.; Bonamo, J.

    1984-01-01

    Twenty patients with tibial plateau fractures were studied by conventional tomography and computed tomography (CT) in order to determine the role and feasibility of CT in management of such patients. CT resulted in less discomfort to the patient and provided optimal visualization of the plateau defect and the split fragments. It proved more accurate than conventional tomography in assessing depressed and split fractures when they involved the anterior or posterior border of the plateau and in demonstrating the extent of fracture comminution. Split fragments with an oblique plane of fracture also were seen better by CT. The degree of fracture depression and separation as measured by the computerized technique was often more accurate than measurements obtained from conventional tomograms

  4. HANFORD SITE CENTRAL PLATEAU CLEANUP COMPLETION STRATEGY

    International Nuclear Information System (INIS)

    Bergman, T.B.

    2011-01-01

    Cleanup of the Hanford Site is a complex and challenging undertaking. The U.S. Department of Energy (DOE) has developed a comprehensive vision for completing Hanford's cleanup mission including transition to post-cleanup activities. This vision includes 3 principle components of cleanup: the ∼200 square miles ofland adjacent to the Columbia River, known as the River Corridor; the 75 square miles of land in the center of the Hanford Site, where the majority of the reprocessing and waste management activities have occurred, known as the Central Plateau; and the stored reprocessing wastes in the Central Plateau, the Tank Wastes. Cleanup of the River Corridor is well underway and is progressing towards completion of most cleanup actions by 2015. Tank waste cleanup is progressing on a longer schedule due to the complexity of the mission, with construction of the largest nuclear construction project in the United States, the Waste Treatment Plant, over 50% complete. With the progress on the River Corridor and Tank Waste, it is time to place increased emphasis on moving forward with cleanup of the Central Plateau. Cleanup of the Hanford Site has been proceeding under a framework defmed in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). In early 2009, the DOE, the State of Washington Department of Ecology, and the U.S. Environmental Protection Agency signed an Agreement in Principle in which the parties recognized the need to develop a more comprehensive strategy for cleanup of the Central Plateau. DOE agreed to develop a Central Plateau Cleanup Completion Strategy as a starting point for discussions. This DOE Strategy was the basis for negotiations between the Parties, discussions with the State of Oregon, the Hanford Advisory Board, and other Stakeholder groups (including open public meetings), and consultation with the Tribal Nations. The change packages to incorporate the Central Plateau Cleanup Completion Strategy were signed by the

  5. Plateau iris secondary to iridociliary cysts.

    Science.gov (United States)

    Vila-Arteaga, J; Díaz-Céspedes, R A; Suriano, M M

    2015-11-01

    We present a case of plateau iris and glaucoma due to multiple unilateral iridociliary cysts. The patient was treated with iridotomy Nd: YAG laser and 360° iridoplasty, without achieving pressure control. Phacoemulsification improved the hypertension. Dynamic gonioscopy and OCT of the anterior chamber was also performed before and after treatment. Iridociliary cysts are a benign condition that can cause iris plateau configuration, and can produce a difficult to treat ocular hypertension. Cystotomy, peripheral iridoplasty, and other treatments have been proposed. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  6. Correction of sub-pixel topographical effects on land surface albedo retrieved from geostationary satellite (FengYun-2D) observations

    International Nuclear Information System (INIS)

    Roupioz, L; Nerry, F; Jia, L; Menenti, M

    2014-01-01

    The Qinghai-Tibetan Plateau is characterised by a very strong relief which affects albedo retrieval from satellite data. The objective of this study is to highlight the effects of sub-pixel topography and to account for those effects when retrieving land surface albedo from geostationary satellite FengYun-2D (FY-2D) data with 1.25km spatial resolution using the high spatial resolution (30 m) data of the Digital Elevation Model (DEM) from ASTER. The methodology integrates the effects of sub-pixel topography on the estimation of the total irradiance received at the surface, allowing the computation of the topographically corrected surface reflectance. Furthermore, surface albedo is estimated by applying the parametric BRDF (Bidirectional Reflectance Distribution Function) model called RPV (Rahman-Pinty-Verstraete) to the terrain corrected surface reflectance. The results, evaluated against ground measurements collected over several experimental sites on the Qinghai-Tibetan Plateau, document the advantage of integrating the sub-pixel topography effects in the land surface reflectance at 1km resolution to estimate the land surface albedo. The results obtained after using sub-pixel topographic correction are compared with the ones obtained after using pixel level topographic correction. The preliminary results imply that, in highly rugged terrain, the sub-pixel topography correction method gives more accurate results. The pixel level correction tends to overestimate surface albedo

  7. Effects of temperature anisotropy on neoclassical transport in the plateau and banana-plateau regimes

    International Nuclear Information System (INIS)

    Taguchi, Masayoshi

    1999-01-01

    The neoclassical transport theory in a presence of temperature anisotropy is investigated in the low to the intermediate collision frequency regimes for a large aspect-ratio tokamak plasma. The standard procedure for an isotropic plasma in the plateau regime is extended to an anisotropic plasma, and the neoclassical transport coefficients in this regime are explicitly calculated. By interpolating the results in the plateau regime and the previously obtained ones in the banana regime, the expressions for the neoclassical transport coefficients which are continuously valid from the banana to the plateau regimes are presented. (author)

  8. Clinical significance of neurocysticercosis in endemic villages

    International Nuclear Information System (INIS)

    García, H.H.; Gilman, R.H.; Tsang, V.C.W.; Gonzalez, A.E.

    1997-01-01

    Cerebral cysticercosis is the main cause of late-onset epilepsy in most developing countries. Data on the neuroepidemiology of cysticercosis in endemic populations is scarce. In an endemic village on the northern coast of Peru, 49 individuals with neurological symptomatology (41 epileptic and 8 non-epileptic) were screened for antibodies to Taenia solium, using a serum electroimmuno transfer blot assay. Fifteen subjects were seropositive, 14 (34%) of those with epilepsy but only one (13%) of those who were non-epileptic. A history of passing proglottides was associated with positive serology. Thirteen of the 15 seropositive individuals underwent cerebral computed tomography; only 7 (54%) were abnormal. A randomly selected sample of 20 pigs from the village was also tested, and 6 (30%) were seropositive. This study demonstrated the importance of cysticercosis in the aetiology of epilepsy in endemic villages and the close relationship between porcine and human infection

  9. Genetic diversity and sex-bias dispersal of plateau pika in Tibetan plateau.

    Science.gov (United States)

    Zhang, Liangzhi; Qu, Jiapeng; Li, Kexin; Li, Wenjing; Yang, Min; Zhang, Yanming

    2017-10-01

    Dispersal is an important aspect in organism's life history which could influence the rate and outcome of evolution of organism. Plateau pika is the keystone species in community of grasslands in Tibetan Plateau. In this study, we combine genetic and field data to character the population genetic pattern and dispersal dynamics in plateau pika ( Ochotona curzoniae ). Totally, 1,352 individual samples were collected, and 10 microsatellite loci were analyzed. Results revealed that plateau pika possessed high genetic diversity and inbreeding coefficient in a fine-scale population. Dispersal distance is short and restricted in about 20 m. An effective sex-biased dispersal strategy is employed by plateau pika: males disperse in breeding period for mating while females do it after reproduction for offspring and resource. Inbreeding avoiding was shown as the common driving force of dispersal, together with the other two factors, environment and resource. In addition, natal dispersal is female biased. More detailed genetic analyzes are needed to confirm the role of inbreeding avoidance and resource competition as ultimate cause of dispersal patterns in plateau pika.

  10. Parasite prevalence in Worthen’s Sparrow (Spizella wortheni: Mexican endemic and endangered species

    Directory of Open Access Journals (Sweden)

    Ricardo Canales-del-Castillo

    2017-10-01

    Full Text Available The Worthen’s sparrow is an endemic bird of the Mexican Plateau that due to its limited distribution and population size is considered to be endangered, both nationally and globally. In general, species at risk have been, at least historically, under population size and genetic diversity reductions, which are factors that can act together to increase infections risk and susceptibility. Therefore, with the purpose to determine such propensity in this species, we analyzed the intestinal parasitic infection through fecal samples from 11 individuals, and hemoparasites, hematocrit and differential leukocyte quantification from one sample. Results indicated that 91% of the samples had one parasite taxon, with genus Cryptosporidium showing the highest prevalence (64%, followed by Eimeria (55%, and Ascaridia (9%. However, mean values of oocysts/eggs per gram indicated a low parasitic infection. We found no blood parasites, and the white blood cell counts were among reference values for other sparrow species.

  11. Endemism in the moss flora of North America.

    Science.gov (United States)

    Carter, Benjamin E; Shaw, Blanka; Shaw, A Jonathan

    2016-04-01

    Identifying regions of high endemism is a critical step toward understanding the mechanisms underlying diversification and establishing conservation priorities. Here, we identified regions of high moss endemism across North America. We also identified lineages that contribute disproportionately to endemism and document the progress of efforts to inventory the endemic flora. To understand the documentation of endemic moss diversity in North America, we tabulated species publication dates to document the progress of species discovery across the continent. We analyzed herbarium specimen data and distribution data from the Flora of North America project to delineate major regions of moss endemism. Finally, we surveyed the literature to assess the importance of intercontinental vs. within-continent diversification for generating endemic species. Three primary regions of endemism were identified and two of these were further divided into a total of nine subregions. Overall endemic richness has two peaks, one in northern California and the Pacific Northwest, and the other in the southern Appalachians. Description of new endemic species has risen steeply over the last few decades, especially in western North America. Among the few studies documenting sister species relationships of endemics, recent diversification appears to have played a larger role in western North America, than in the east. Our understanding of bryophyte endemism continues to grow rapidly. Large continent-wide data sets confirm early views on hotspots of endemic bryophyte richness and indicate a high rate of ongoing species discovery in North America. © 2016 Botanical Society of America.

  12. PLATEAUING COSMIC RAY DETECTORS TO ACHIEVE OPTIMUM OPERATING VOLTAGE

    Energy Technology Data Exchange (ETDEWEB)

    Knoff, E.N.; Peterson, R.S.

    2008-01-01

    Through QuarkNet, students across the country have access to cosmic ray detectors in their high school classrooms. These detectors operate using a scintillator material and a photomultiplier tube (PMT). A data acquisition (DAQ) board counts cosmic ray hits from the counters. Through an online e-Lab, students can analyze and share their data. In order to collect viable data, the PMTs should operate at their plateau voltages. In these plateau ranges, the number of counts per minute remains relatively constant with small changes in PMT voltage. We sought to plateau the counters in the test array and to clarify the plateauing procedure itself. In order to most effectively plateau the counters, the counters should be stacked and programmed to record the number of coincident hits as well as their singles rates. We also changed the threshold value that a signal must exceed in order to record a hit and replateaued the counters. For counter 1, counter 2, and counter 3, we found plateau voltages around 1V. The singles rate plateau was very small, while the coincidence plateau was very long. The plateau voltages corresponded to a singles rate of 700–850 counts per minute. We found very little effect of changing the threshold voltages. Our chosen plateau voltages produced good performance studies on the e-Lab. Keeping in mind the nature of the experiments conducted by the high school students, we recommend a streamlined plateauing process. Because changing the threshold did not drastically affect the plateau voltage or the performance study, students should choose a threshold value, construct plateau graphs, and analyze their data using a performance study. Even if the counters operate slightly off their plateau voltage, they should deliver good performance studies and return reliable results.

  13. [Surgical approaches to tibial plateau fractures].

    Science.gov (United States)

    Krause, Matthias; Müller, Gunnar; Frosch, Karl-Heinz

    2018-06-06

    Intra-articular tibial plateau fractures can present a surgical challenge due to complex injury patterns and compromised soft tissue. The treatment goal is to spare the soft tissue and an anatomical reconstruction of the tibial articular surface. Depending on the course of the fracture, a fracture-specific access strategy is recommended to provide correct positioning of the plate osteosynthesis. While the anterolateral approach is used in the majority of lateral tibial plateau fractures, only one third of the joint surface is visible; however, posterolateral fragments require an individual approach, e. g. posterolateral or posteromedial. If necessary, osteotomy of the femoral epicondyles can improve joint access for reduction control. Injuries to the posterior columns should be anatomically reconstructed and biomechanically correctly addressed via posterior approaches. Bony posterior cruciate ligament tears can be refixed via a minimally invasive posteromedial approach.

  14. Plateau's problem an invitation to varifold geometry

    CERN Document Server

    Frederick J Almgren, Jr

    2001-01-01

    There have been many wonderful developments in the theory of minimal surfaces and geometric measure theory in the past 25 to 30 years. Many of the researchers who have produced these excellent results were inspired by this little book--or by Fred Almgren himself. The book is indeed a delightful invitation to the world of variational geometry. A central topic is Plateau's Problem, which is concerned with surfaces that model the behavior of soap films. When trying to resolve the problem, however, one soon finds that smooth surfaces are insufficient: Varifolds are needed. With varifolds, one can obtain geometrically meaningful solutions without having to know in advance all their possible singularities. This new tool makes possible much exciting new analysis and many new results. Plateau's problem and varifolds live in the world of geometric measure theory, where differential geometry and measure theory combine to solve problems which have variational aspects. The author's hope in writing this book was to encour...

  15. Collision-induced post-plateau volcanism: Evidence from a seamount on Ontong Java Plateau

    Science.gov (United States)

    Hanyu, Takeshi; Tejada, Maria Luisa G.; Shimizu, Kenji; Ishizuka, Osamu; Fujii, Toshiyuki; Kimura, Jun-Ichi; Chang, Qing; Senda, Ryoko; Miyazaki, Takashi; Hirahara, Yuka; Vaglarov, Bogdan S.; Goto, Kosuke T.; Ishikawa, Akira

    2017-12-01

    Many seamounts on the Ontong Java Plateau (OJP) occur near the Stewart Arch, a topographic high that extends parallel to the North Solomon Trench along the southern margins of the plateau. Despite the thick sediment cover, several volcanic cones with strong acoustic reflection were discovered on the submarine flank of the Nuugurigia Seamount. From such volcanic cones, basalts were successfully sampled by dredging. Radiometric dating of basalts and ferromanganese encrustation indicate eruption age of 20-25 Ma, significantly younger than the 122 Ma main OJP plateau and post-plateau basalts. The age range coincides with the collision of the OJP with the Solomon Arc. The Nuugurigia basalts geochemically differ from any other rocks sampled on the OJP so far. They are alkali basalts with elevated Sr, low Zr and Hf, and Enriched Mantle-I (EMI)-like isotopic composition. Parental magmas of these alkali basalts may have formed by small-degree melting of peridotitic mantle impregnated with recycled pyroxenite material having enriched geochemical composition in the OJP's mantle root. We conclude that small-volume alkali basalts from the enriched mantle root migrated through faults or fractures caused by the collision along the Stewart Arch to form the seamount. Our results suggest that the collision of the OJP with the Solomon arc played an important role in the origin of similar post-plateau seamounts along the Stewart Arch.

  16. Rapid assessment of endemic bird areas in Michoacan, Mexico

    Science.gov (United States)

    Gilberto Chavez-Leon; Deborah M. Finch

    1999-01-01

    Non-sustainable land use practices in the state of Michoacan, Mexico, have perturbed endemic bird h~bitats for several decades. Endemic birds have a restricted geographic and ecological distribution. This feature makes them suitable to be used as indicators of biological diversity and environmental perturbation. Forty-one Mexican endemic species have been recorded in...

  17. Endemicity of cholera in Nigeria: A mathematical model to ...

    African Journals Online (AJOL)

    The focal point is to investigate the persistent endemic nature of cholera in Nigeria using mathematical model. We found that, there can be no backward bifurcation because there existed only one positive endemic equilibrium. In other words, it is not possible for multiple endemic equilibria to exist if the reproduction number ...

  18. Patterns of distribution and protection status of the endemic ...

    African Journals Online (AJOL)

    1995-06-02

    Jun 2, 1995 ... South Africa contains the majority of southern Africa's endemic mammals and hence is an important ... example of an archaic fauna that has undergone local radia- ... Indeed, only six of South Africa's endemic. R eprodu ced by Sabin et G atew ..... of the endemic flora of this region is renowned (Cowling,.

  19. Endemics and Pseudo-Endemics in Relation to the Distribution Patterns of Indian Pteridophytes

    Directory of Open Access Journals (Sweden)

    C. R. Fraser-Jenkins

    2008-09-01

    Full Text Available Of c. 530 Pteridophytes reported as endemic to the India in recent decades (about half the total number of c. 950-1000 known Indian species, the great bulk are mistaken, particularly those from the Indo-Himalaya. Only 47 endemic Indian ferns, less than 10% of those reported previously, are accepted here. But this figure includes several that are rather doubtfully endemic, mainly due to unresolved taxonomic doubt, or because they may be expected to occur in adjacent Countries. Thus 8 are taxonomically dubious, requiring further study, and a further 7, all from N.E. India, may possibly be expected elsewhere outside India. The c. 483 mistaken pseudo-endemics arose mainly due to naming of erroneous 'new species' thought to be endemic, or due to not knowing the range of species outside political India, combined with insufficient investigative taxonomic research. In the present paper previous reports of endemics are listed and their status is reappraised along with a new list of accepted endemics. Quite opposite to previous conclusions, the great majority of endemic Indian Pteridophytes are peninsular-Indian to south-Indian ferns (27, plus 5 more taxonomically dubious, with far fewer being N.E. Indian (7, all of which may possibly be expected elsewhere outside India and W. Himalayan (2, plus 1 taxonomically dubious; the floristically Malesian Nicobar Islands have (3, plus 2 more taxonomically dubious. These numbers are only to be expected as N.E. India is an intimate part of the Sino-Himalayan and S.E. Asian flora, connected without barriers to Tibet and China or to Myanmar by two mountain chains, while S. India is more isolated geographically since more ancient times and has a partly Malesian fern-flora. Some details of Indian endemics in relation to phytogeographical elements are given. Endemic species: Huperzia - 1, Selaginella - 9, Isoetes - 1, Osmunda - 1, Arthromeris - 1, Phymatosorus - 1, Oreogrammitis - 2, Trichomanes - 1, Pteris - 1, Cyathea

  20. Taxonomic composition and endemism of the helminth fauna of freshwater fishes of Mexico.

    Science.gov (United States)

    Salgado-Maldonado, Guillermo; Quiroz-Martínez, Benjamín

    2013-01-01

    We examine the taxonomic composition and endemism of adult helminth parasites of freshwater fishes of Mexico, with regard to the main hydrological basins of the country. A presence-absence matrix, including every species of adult helminth parasites of freshwater fishes from 23 Mexican hydrological basins was compiled and examined in this paper. The helminth fauna of freshwater fishes of Mexico consists of a large group of Central American Neotropical species (S = 119) and another set, less rich of Nearctic species (S = 48), which are distributed along with the families of its fish hosts; insufficient data preclude the assignation of three species. This fauna is composed predominantly by nematodes, trematodes, and monogeneans, which together contributed 86 % of the total species recorded; cestodes and acanthocephalans being the taxa with the least species recorded. Current data suggests a 22 % (37/170) endemism amongst helminths of freshwater fishes of Mexico. Data suggests that the isolation of bodies of water in the Mexican territory, mostly in the Neotropical areas of southeastern Mexico and in the central Altiplano Mexicano (Mexican Highland Plateau), with well delimited basins separated by orographic features, provided peculiar conditions that have been conducive to the diversification of a unique helminth fauna.

  1. Therapy of endemic goiter and hypothyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Luft, D.

    1983-09-12

    Successful treatment of endemic goitre depends on the correct diagnosis and the comprehension of the pathophysiologic changes as well. Several criteria, e.g. anamnestic data, general clinical condition, local symptoms and signs, certainty of diagnosis, contraindications, rates of success, and side effects, determine the particular form of therapy (suppression with thyroid hormones, surgical resection, radio-iodine). The decision criteria are discussed. Prophylaxis of recurrent goitre with either thyroid hormones or iodine salts is necessary after successful treatment. Some endemic goitres behave like either hyper- or hypothyroidism. Treatment with thyroid hormones of patients with latent hyperthyroidism is senseless and dangerous, whereas other methods of treatment may be applied. An unequivocal indication for treatment exists in patients with latent hypothyroidism accompanied by goitre, but not in all patients without goitre. Hormonal replacement therapy of manifest hypothydroidism is simple, but long term success is not achieved in all patients.

  2. Therapy of endemic goiter and hypothyroidism

    International Nuclear Information System (INIS)

    Luft, D.

    1983-01-01

    Successful treatment of endemic goitre depends on the correct diagnosis and the comprehension of the pathophysiologic changes as well. Several criteria, e.g. anamnestic data, general clinical condition, local symptoms and signs, certainty of diagnosis, contraindications, rates of success, and side effects, determine the particular form of therapy (suppression with thyroid hormones, surgical resection, radio-iodine). The decision criteria are discussed. Prophylaxis of recurrent goitre with either thyroid hormones or iodine salts is necessary after successful treatment. Some endemic goitres behave like either hyper- or hypothyroidism. Treatment with thyroid hormones of patients with latent hyperthyroidism is senseless and dangerous, whereas other methods of treatment may be applied. An unequivocal indication for treatment exists in patients with laent hypothyroidism accompanied by goitre, but not in all patients without goitre. Hormonal replacement therapy of manifest hypothydroidism is simple, but long term success is not achieved in all patients. (orig.) [de

  3. The endemic gastropod fauna of Lake Titicaca: correlation between molecular evolution and hydrographic history.

    Science.gov (United States)

    Kroll, Oliver; Hershler, Robert; Albrecht, Christian; Terrazas, Edmundo M; Apaza, Roberto; Fuentealba, Carmen; Wolff, Christian; Wilke, Thomas

    2012-07-01

    Lake Titicaca, situated in the Altiplano high plateau, is the only ancient lake in South America. This 2- to 3-My-old (where My is million years) water body has had a complex history that included at least five major hydrological phases during the Pleistocene. It is generally assumed that these physical events helped shape the evolutionary history of the lake's biota. Herein, we study an endemic species assemblage in Lake Titicaca, composed of members of the microgastropod genus Heleobia, to determine whether the lake has functioned as a reservoir of relic species or the site of local diversification, to evaluate congruence of the regional paleohydrology and the evolutionary history of this assemblage, and to assess whether the geographic distributions of endemic lineages are hierarchical. Our phylogenetic analyses indicate that the Titicaca/Altiplano Heleobia fauna (together with few extralimital taxa) forms a species flock. A molecular clock analysis suggests that the most recent common ancestor (MRCAs) of the Altiplano taxa evolved 0.53 (0.28-0.80) My ago and the MRCAs of the Altiplano taxa and their extralimital sister group 0.92 (0.46-1.52) My ago. The endemic species of Lake Titicaca are younger than the lake itself, implying primarily intralacustrine speciation. Moreover, the timing of evolutionary branching events and the ages of two precursors of Lake Titicaca, lakes Cabana and Ballivián, is congruent. Although Lake Titicaca appears to have been the principal site of speciation for the regional Heleobia fauna, the contemporary spatial patterns of endemism have been masked by immigration and/or emigration events of local riverine taxa, which we attribute to the unstable hydrographic history of the Altiplano. Thus, a hierarchical distribution of endemism is not evident, but instead there is a single genetic break between two regional clades. We also discuss our findings in relation to studies of other regional biota and suggest that salinity tolerance was

  4. Chemical erosion and hydrologic budget for the Susure karst plateau

    Directory of Open Access Journals (Sweden)

    Nikić Zoran

    2010-01-01

    Full Text Available The karst plateau of Susure, about 4.5 km2 in surface area, is situated on the Jadovnik eastern offset, western Serbia. The plateau is a morphologic unit higher 15 m to 30 m than the surrounding terrain. The unit consists of crushed and karstified Middle Triassic limestones. Numerous hydrogeological and geomorphologic features of the plateau are attractive for visitors in this economically underdeveloped country. Rocks building up the surrounding terrain are largely peridotites. Surface streams flow neither into nor off the plateau. Atmospheric precipitations discharge to evapotanspiration and filtration underground. More than eighteen constant springs at the limestone/peridotite tectonic contact drain fracture aquifers on the karst plateau border. Measured precipitations and springflows were the input and output data for accounting water budget of an aquifer of Middle Triassic limestones in the Susure plateau.

  5. Temperature and snowfall trigger alpine vegetation green-up on the world's roof.

    Science.gov (United States)

    Chen, Xiaoqiu; An, Shuai; Inouye, David W; Schwartz, Mark D

    2015-10-01

    Rapid temperature increase and its impacts on alpine ecosystems in the Qinghai-Tibetan Plateau, the world's highest and largest plateau, are a matter of global concern. Satellite observations have revealed distinctly different trend changes and contradicting temperature responses of vegetation green-up dates, leading to broad debate about the Plateau's spring phenology and its climatic attribution. Large uncertainties in remote-sensing estimates of phenology significantly limit efforts to predict the impacts of climate change on vegetation growth and carbon balance in the Qinghai-Tibetan Plateau, which are further exacerbated by a lack of detailed ground observation calibration. Here, we revealed the spatiotemporal variations and climate drivers of ground-based herbaceous plant green-up dates using 72 green-up datasets for 22 herbaceous plant species at 23 phenological stations, and corresponding daily mean air temperature and daily precipitation data from 19 climate stations across eastern and southern parts of the Qinghai-Tibetan Plateau from 1981 to 2011. Results show that neither the continuously advancing trend from 1982 to 2011, nor a turning point in the mid to late 1990s as reported by remote-sensing studies can be verified by most of the green-up time series, and no robust evidence for a warmer winter-induced later green-up dates can be detected. Thus, chilling requirements may not be an important driver influencing green-up responses to spring warming. Moreover, temperature-only control of green-up dates appears mainly at stations with relatively scarce preseason snowfall and lower elevation, while coupled temperature and precipitation controls of green-up dates occur mostly at stations with relatively abundant preseason snowfall and higher elevation. The diversified interactions between snowfall and temperature during late winter to early spring likely determine the spatiotemporal variations of green-up dates. Therefore, prediction of vegetation growth

  6. Happily Ever After: Plateauing as a Means for Long-Term Career Satisfaction.

    Science.gov (United States)

    Montgomery, Denise L.

    2002-01-01

    Discusses plateauing as a means for long-term career satisfaction, Highlights include a literature review; what plateauing is and why it occurs, including career-based plateauing and life plateauing; some solutions to plateauing for librarians, including management changes and individual changes; and personal examples. (LRW)

  7. Colorado Plateau magmatism and uplift by warming of heterogeneous lithosphere.

    Science.gov (United States)

    Roy, Mousumi; Jordan, Thomas H; Pederson, Joel

    2009-06-18

    The forces that drove rock uplift of the low-relief, high-elevation, tectonically stable Colorado Plateau are the subject of long-standing debate. While the adjacent Basin and Range province and Rio Grande rift province underwent Cenozoic shortening followed by extension, the plateau experienced approximately 2 km of rock uplift without significant internal deformation. Here we propose that warming of the thicker, more iron-depleted Colorado Plateau lithosphere over 35-40 Myr following mid-Cenozoic removal of the Farallon plate from beneath North America is the primary mechanism driving rock uplift. In our model, conductive re-equilibration not only explains the rock uplift of the plateau, but also provides a robust geodynamic interpretation of observed contrasts between the Colorado Plateau margins and the plateau interior. In particular, the model matches the encroachment of Cenozoic magmatism from the margins towards the plateau interior at rates of 3-6 km Myr(-1) and is consistent with lower seismic velocities and more negative Bouguer gravity at the margins than in the plateau interior. We suggest that warming of heterogeneous lithosphere is a powerful mechanism for driving epeirogenic rock uplift of the Colorado Plateau and may be of general importance in plate-interior settings.

  8. Therapeutical Management of the Tibial Plateau Fractures

    Directory of Open Access Journals (Sweden)

    Obada B.

    2016-11-01

    Full Text Available The study was aimed to identify the role of surgical treatment of tibial plateau fractures, its functional outcome and complications. Demographic data for the patients and details of current clinical and radiological follow-up findings were obtained to assess range of motion, clinical stability, alignment of the knee, and posttraumatic arthrosis (Kellgren/Lawrence score. 64 cases of tibial plateau fractures treated by different surgical methods and variuos implants type were studied from 2013 to 2015 and followed-up for minimum period of 6 months. The systematisation of the casuitry was made using Schatzker and AO classifications. The treatment methods consist of: percutaneous cannulated cancellous screws, ORIF with buttress plate with or without bone grafting, locking or nonlocking plates, external fixator. As complications we found: redepression 4 case, malunion 2 cases, knee stiffness 9, wound dehiscence in 1 cases and non-union or infection in none of our cases. The average flexion of the injured knee was significantly lower in comparison with the contralateral side (124.9°/135.2°. Knee stability did not differ statistically significantly. There were no signs of posttraumatic arthrosis in 45% of cases, mild signs in 30%, clear signs in 18%, and severe signs in 7%. As conclusion we found that surgical management of tibial plateau fractures will give excellent anatomical reduction and rigid fixation to restore articular congruity, facilitate early motion and reduce arthrosis risk and hence to achieve optimal knee function. The choice of optimal surgical methods, proper approach and implant is made in relation to fracture type according Schatzker and AO classification.

  9. Vertebrate Fossils Imply Paleo-elevations of the Tibetan Plateau

    Science.gov (United States)

    Deng, T.; Wang, X.; Li, Q.; Wu, F.; Wang, S.; Hou, S.

    2017-12-01

    The uplift of the Tibetan Plateau remains unclear, and its paleo-elevation reconstructions are crucial to interpret the geodynamic evolution and to understand the climatic changes in Asia. Uplift histories of the Tibetan Plateau based on different proxies differ considerably, and two viewpoints are pointedly opposing on the paleo-elevation estimations of the Tibetan Plateau. One viewpoint is that the Tibetan Plateau did not strongly uplift to reach its modern elevation until the Late Miocene, but another one, mainly based on stable isotopes, argues that the Tibetan Plateau formed early during the Indo-Asian collision and reached its modern elevation in the Paleogene or by the Middle Miocene. In 1839, Hugh Falconer firstly reported some rhinocerotid fossils collected from the Zanda Basin in Tibet, China and indicated that the Himalayas have uplifted by more than 2,000 m since several million years ago. In recent years, the vertebrate fossils discovered from the Tibetan Plateau and its surrounding areas implied a high plateau since the late Early Miocene. During the Oligocene, giant rhinos lived in northwestern China to the north of the Tibetan Plateau, while they were also distributed in the Indo-Pakistan subcontinent to the south of this plateau, which indicates that the elevation of the Tibetan Plateau was not too high to prevent exchanges of large mammals; giant rhinos, the rhinocerotid Aprotodon, and chalicotheres still dispersed north and south of "Tibetan Plateau". A tropical-subtropical lowland fish fauna was also present in the central part of this plateau during the Late Oligocene, in which Eoanabas thibetana was inferred to be closely related to extant climbing perches from South Asia and Sub-Saharan Africa. In contrast, during the Middle Miocene, the shovel-tusked elephant Platybelodon was found from many localities north of the Tibetan Plateau, while its trace was absent in the Siwaliks of the subcontinent, which implies that the Tibetan Plateau had

  10. [Operative treatment for complex tibial plateau fractures].

    Science.gov (United States)

    Song, Qi-Zhi; Li, Tao

    2012-03-01

    To explore the surgical methods and clinical evaluation of complex tibial plateau fractures resulted from high-energy injuries. From March 2006 to May 2009,48 cases with complex tibial plateau fractures were treated with open reduction and plate fixation, including 37 males and 11 females, with an average age of 37 years (ranged from 18 to 63 years). According to Schatzker classification, 16 cases were type IV, 20 cases type V and 12 cases type VI. All patients were examined by X-ray flim and CT scan. The function of knee joint were evaluated according to postoperative follow-up X-ray and Knee Merchant Rating. Forty-eight patients were followed up with a mean time of 14 months. According to Knee Merchant Rating, 24 cases got excellent results, 16 cases good, 6 cases fair and 2 cases poor. Appropriate operation time, anatomical reduction, suitable bone graft and reasonable rehabilitation exercises can maximally recovery the function of knee joint.

  11. Optimising Regionalisation Techniques: Identifying Centres of Endemism in the Extraordinarily Endemic-Rich Cape Floristic Region

    Science.gov (United States)

    Bradshaw, Peter L.; Colville, Jonathan F.; Linder, H. Peter

    2015-01-01

    We used a very large dataset (>40% of all species) from the endemic-rich Cape Floristic Region (CFR) to explore the impact of different weighting techniques, coefficients to calculate similarity among the cells, and clustering approaches on biogeographical regionalisation. The results were used to revise the biogeographical subdivision of the CFR. We show that weighted data (down-weighting widespread species), similarity calculated using Kulczinsky’s second measure, and clustering using UPGMA resulted in the optimal classification. This maximized the number of endemic species, the number of centres recognized, and operational geographic units assigned to centres of endemism (CoEs). We developed a dendrogram branch order cut-off (BOC) method to locate the optimal cut-off points on the dendrogram to define candidate clusters. Kulczinsky’s second measure dendrograms were combined using consensus, identifying areas of conflict which could be due to biotic element overlap or transitional areas. Post-clustering GIS manipulation substantially enhanced the endemic composition and geographic size of candidate CoEs. Although there was broad spatial congruence with previous phytogeographic studies, our techniques allowed for the recovery of additional phytogeographic detail not previously described for the CFR. PMID:26147438

  12. Loess Thickness Variations Across the Loess Plateau of China

    Science.gov (United States)

    Zhu, Yuanjun; Jia, Xiaoxu; Shao, Mingan

    2018-01-01

    The soil thickness is very important for investigating and modeling soil-water processes, especially on the Loess Plateau of China with its deep loess deposit and limited water resources. A digital elevation map (DEM) of the Loess Plateau and neighborhood analysis in ArcGIS software were used to generate a map of loess thickness, which was then validated by 162 observations across the plateau. The generated loess thickness map has a high resolution of 100 m × 100 m. The map indicates that loess is thick in the central part of the plateau and becomes gradually shallower in the southeast and northwest directions. The areas near mountains and river basins have the shallowest loess deposit. The mean loess thickness is the deepest in the zones with 400-600-mm precipitation and decreases gradually as precipitation varies beyond this range. Our validation indicates that the map just slightly overestimates loess thickness and is reliable. The loess thickness is mostly between 0 and 350 m in the Loess Plateau region. The calculated mean loess thickness is 105.7 m, with the calibrated value being 92.2 m over the plateau exclusive of the mountain areas. Our findings provide very basic data of loess thickness and demonstrate great progress in mapping the loess thickness distribution for the plateau, which are valuable for a better study of soil-water processes and for more accurate estimations of soil water, carbon, and solute reservoirs in the Loess Plateau of China.

  13. Geochemical characteristics of the Jos-Plateau Basalts, North ...

    African Journals Online (AJOL)

    The Jos Plateau basalts, present Zr/Nb ratios (2.4-3.0) comparable to those of the alkali basalts of the lower Benue valley, and of the Cameroon volcanic line, suggesting that they were possibly derived from the same mantle source. Keywords: Jos Plateau, alkali basalt, mantle, partial melting, incompatible elements.

  14. Taenia solium in Europe: Still endemic?

    Science.gov (United States)

    Devleesschauwer, Brecht; Allepuz, Alberto; Dermauw, Veronique; Johansen, Maria V; Laranjo-González, Minerva; Smit, G Suzanne A; Sotiraki, Smaragda; Trevisan, Chiara; Wardrop, Nicola A; Dorny, Pierre; Gabriël, Sarah

    2017-01-01

    The pork tapeworm, Taenia solium, causes an important economic and health burden, mainly in rural or marginalized communities of sub-Saharan Africa, Asia, and Latin-America. Although improved pig rearing conditions seem to have eliminated the parasite in most Western European countries, little is known about the true endemicity status of T. solium throughout Europe. Three recent reviews indicate that autochthonous human T. solium taeniasis/cysticercosis may be possible in Europe, but that current peer-reviewed literature is biased towards Western Europe. Officially reported data on porcine cysticercosis are highly insufficient. Favourable conditions for local T. solium transmission still exist in eastern parts of Europe, although the ongoing integration of the European Union is speeding up modernisation and intensification of the pig sector. Further evidence is urgently needed to fill the gaps on the European T. solium endemicity map. We urge to make human cysticercosis notifiable and to improve the reporting of porcine cysticercosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Diversity and endemism of Peruvian mammals

    Directory of Open Access Journals (Sweden)

    Víctor Pacheco

    2011-07-01

    Full Text Available We present an annotated list for all land, aquatic and marine mammals known to occur in Peru and their distribution by ecoregions. We also present species conservation status according to international organizations and the legal conservation status in Peru. At present, we record 508 species, in 13 orders, 50 families, and 218 genera, making Peru the third most diverse country with regards to mammals in the New World, after Brazil and Mexico, and the fifth most diverse country for mammals in the World. This diversity includes 40 didelphimorphs, 2 paucituberculates, 1 manatee, 6 cingulates, 7 pilosa, 39 primates, 162 rodents, 1 rabbit, 2 soricomorphs, 165 bats, 34 carnivores, 2 perissodactyls, and 47 cetartiodactyls. Bats and rodents (327 species represent almost two thirds of total diversity (64% for Peru. Five genera and 65 species (12.8% are endemics to Peru, with the majority of these being rodents (45 species, 69,2%. Most of the endemic species are restricted to the Yungas of the eastern slope of the Andes (39 species, 60% followed by Selva Baja (14 species, 21.5%. The taxonomic status of some species is commented on, when those depart from accepted taxonomy. The marsupial Marmosa phaea; the rodents Melanomys caliginosus, M. robustulus, and Echinoprocta rufescens; the shrew Cryptotis equatoris; the bats Anoura fistulata, Phyllostomus latifolius, Artibeus ravus, Cynomops greenhalli, Eumops maurus, and Rhogeessa velilla; and the carnivore Nasuella olivacea are first records of species occurrence in Peru. Finally, we also include a list of 15 non-native species.

  16. Parhelic-like circle from light scattering in Plateau borders

    Energy Technology Data Exchange (ETDEWEB)

    Tufaile, A., E-mail: tufaile@usp.br; Tufaile, A.P.B.

    2015-03-06

    We are reporting a new simple optical element to generate halos. We have observed interesting patterns of light scattering in Plateau borders in foams. In analogy to the atmospheric phenomena known as parhelic circle, sun dogs, and sun pillars, we have named the features of the patterns observed as parlaseric circle, laser dogs, and laser pillars. The triangular symmetry of the Plateau borders is analogous to the hexagonal symmetry of ice crystals which produce these atmospheric phenomena. Working with one Plateau border at a time, we have observed wave optics phenomena that are not perceived in the atmospheric phenomena, such as diffraction and interference. - Highlights: • We obtained halo formation from light scattering in a Plateau border using an experiment. • We explained halo formation using geometrical theory of diffraction. • An optical element based on a Plateau border is proposed. • We compared some aspects of the parhelic circle with the parlaseric circle.

  17. Hydroclimatological Controls of Endemic and Non-endemic Cholera of the 20th Century

    Science.gov (United States)

    Jutla, A. S.; Whitcombe, E.; Colwell, R.

    2012-12-01

    Cholera remains a major public health threat for the developing countries. Since the causative agent, Vibrio cholerae, is autochthonous to aquatic environment, it is not possible to eradicate the agent of the disease. Hydroclimatology based prediction and prevention strategies can be implemented in disease susceptible regions for reducing incidence rates. However, the precise role of hydrological and climatological processes, which will further aid in development of suitable prediction models, in creating spatial and temporal environmental conditions favorable for disease outbreak has not been adequately quantified. Here, we show distinction between seasonality and occurrence of cholera in epidemic and non-endemic regions. Using historical cholera mortality data, from the late 1800s for 27 locations in the Indian subcontinent, we show that non-endemic regions are generally located close to regional river systems but away from the coasts and are characterized by single sporadic outbreak in a given year. Increase in air temperature during the low river flow season increases evaporation, leading to an optimal salinity and pH required for bacterial growth. Thereafter, monsoonal rainfall, leads to interactions of contaminated river waters via human activity resulting in cholera epidemics. Endemic regions are located close to coasts where cholera outbreak occurs twice (spring and fall) in a year. Spring outbreak is generally associated with intrusion of bacterial seawater to inland whereas the fall peak is correlated with widespread flooding and cross-contamination of water resources via increased precipitation. This may be one of the first studies to hydroclimatologically quantitatively the seasonality of cholera in both endemic and non-endemic regions. Our results prompt the need of region and cause-specific prediction models for cholera, employing appropriate environmental determinants.

  18. Heat flow in the north-central Colorado Plateau

    International Nuclear Information System (INIS)

    Bodell, J.M.; Chapman, D.S.

    1982-01-01

    We report new heat flow measurements at 25 evenly distributed sites in the north-central Colorado Plateau. Heat flow values computed for these new sites and one previously published site range from 43 to 116 mW m -2 but fall into the following district subsets related to physiographic and tectonic elements within the Plateau: (1) heat flow of 51 mW m -2 (12 sites; s.d. 6) in the San Rafael Swell and Green River Desert which constitute the core of the Colorado Plateau at this latitude, (2) heat flows of 69 mW m -2 (5 sites; s.d. 10) in successive parallel north-south bands approaching the Wasatch Plateau to the west but still 80 km east of the Basin and Range physiographic boundary, (3) heat flow of 64 mW m -2 (5 sites; s.d. 2) along the Salt Anticline trend which strikes northwest in the region of Moab, Utah. Heat flow results for the entire Colorado Plateau have been reexamined in view of our new results, and the overall pattern supports the concept of a low heat flow 'thermal interior' for the plateau surrounded by a periphery some 100 km wide having substantially higher heat flow. Average heat flow in the thermal interior is about 60 mW m -2 compared to 80--90 mW m -2 in the periphery. This regional heat flow pattern supports a model of tertiary lithospheric thinning under the Colorado Plateau whereby the plateau is still in transient thermal response and a 15--20 m.y. lag between uplift and corresponding surface heat flow anomaly is to be expected. The position of the heat flow transition between our interior and peripheral regions in the northwest plateau is roughly consistent with lateral warming and weakening of the Colorado Plateau lithosphere initiated at the Basin and Range boundary some 20 m.y. ago

  19. Satellite precipitation estimation over the Tibetan Plateau

    Science.gov (United States)

    Porcu, F.; Gjoka, U.

    2012-04-01

    Precipitation characteristics over the Tibetan Plateau are very little known, given the scarcity of reliable and widely distributed ground observation, thus the satellite approach is a valuable choice for large scale precipitation analysis and hydrological cycle studies. However,the satellite perspective undergoes various shortcomings at the different wavelengths used in atmospheric remote sensing. In the microwave spectrum often the high soil emissivity masks or hides the atmospheric signal upwelling from light-moderate precipitation layers, while low and relatively thin precipitating clouds are not well detected in the visible-infrared, because of their low contrast with cold and bright (if snow covered) background. In this work an IR-based, statistical rainfall estimation technique is trained and applied over the Tibetan Plateau hydrological basin to retrive precipitation intensity at different spatial and temporal scales. The technique is based on a simple artificial neural network scheme trained with two supervised training sets assembled for monsoon season and for the rest of the year. For the monsoon season (estimated from June to September), the ground radar precipitation data for few case studies are used to build the training set: four days in summer 2009 are considered. For the rest of the year, CloudSat-CPR derived snowfall rate has been used as reference precipitation data, following the Kulie and Bennartz (2009) algorithm. METEOSAT-7 infrared channels radiance (at 6.7 and 11 micometers) and derived local variability features (such as local standard deviation and local average) are used as input and the actual rainrate is obtained as output for each satellite slot, every 30 minutes on the satellite grid. The satellite rainrate maps for three years (2008-2010) are computed and compared with available global precipitation products (such as C-MORPH and TMPA products) and with other techniques applied to the Plateau area: similarities and differences are

  20. Comparison of immune responses to a killed bivalent whole cell oral cholera vaccine between endemic and less endemic settings.

    Science.gov (United States)

    Desai, Sachin N; Akalu, Zenebe; Teferi, Mekonnen; Manna, Byomkesh; Teshome, Samuel; Park, Ju Yeon; Yang, Jae Seung; Kim, Deok Ryun; Kanungo, Suman; Digilio, Laura

    2016-02-01

    Studies on safety, immunogenicity and efficacy of the killed, bivalent whole cell oral cholera vaccine (Shanchol) have been conducted in historically endemic settings of Asia. Recent cholera vaccination campaigns in Haiti and Guinea have also demonstrated favourable immunogenicity and effectiveness in nonendemic outbreak settings. We performed a secondary analysis, comparing immune responses of Shanchol from two randomised controlled trials performed in an endemic and a less endemic area (Addis Ababa) during a nonoutbreak setting. While Shanchol may offer some degree of immediate protection in primed populations living in cholera endemic areas, as well as being highly immunogenic in less endemic settings, understanding the characteristics of immune responses in each of these areas is vital in determining ideal dosing strategies that offer the greatest public health impact to populations from areas with varying degrees of cholera endemicity. © 2015 John Wiley & Sons Ltd.

  1. Uranium indicator plants of the Colorado plateau

    International Nuclear Information System (INIS)

    Massingill, G.L.

    1979-01-01

    Two methods of botanical prospecting for uranium deposits have been applied on the Colorado Plateau. The first, based on a chemical analysis of deep-rooted plants that absorb uranium from ore bodies, detects small but measurable amounts of the element in plants rooted in ore. A second method involves mapping the distribution of indicator plants because these plants are dependent--either directly or indirectly--upon the presence of abnormally high levels of elements in the parent soil or rock. Botanical prospecting studies made in ten districts have been productive. In the Thompson district, Grand County, Utah, five ore bodies were found solely on the basis of indicator plant data. 15 refs

  2. Plateau inflation in SUGRA-MSSM

    Directory of Open Access Journals (Sweden)

    Girish Kumar Chakravarty

    2016-09-01

    Full Text Available We explored a Higgs inflationary scenario in the SUGRA embedding of the MSSM in Einstein frame where the inflaton is contained in the SU(2 Higgs doublet. We include all higher order non-renormalizable terms to the MSSM superpotential and an appropriate Kähler potential which can provide slow-roll inflaton potential in the D-flat direction. In this model, a plateau-like inflation potential can be obtained if the imaginary part of the neutral Higgs acts as the inflaton. The inflationary predictions of this model are consistent with the latest CMB observations. The model represents a successful Higgs inflation scenario in the context of Supergravity and it is compatible with Minimal Supersymmetric extension of the Standard Model.

  3. Endemic human fasciolosis in the Bolivian Altiplano.

    Science.gov (United States)

    Parkinson, M; O'Neill, S M; Dalton, J P

    2007-05-01

    Fasciolosis, caused by trematodes of the genus Fasciola, is an emerging disease of humans. One of the highest levels of human fasciolosis hepatica is found amongst the indigenous Aymaran people of the Northern Bolivian Altiplano. A meta-analysis of epidemiological surveys from 38 communities in the region demonstrates that fasciolosis has been endemic in the region since at least 1984 and is a zoonosis of rural communities. Human and bovine fasciolosis is associated with the communities lying in the plain from Lake Titicaca to La Paz, predominantly in the Los Andes province. In Los Andes incidences of up to 67% of population cohorts were found, and prevalence is age-related with the highest infection rate in children aged 8-11 years.

  4. Bursting endemic bubbles in an adaptive network

    Science.gov (United States)

    Sherborne, N.; Blyuss, K. B.; Kiss, I. Z.

    2018-04-01

    The spread of an infectious disease is known to change people's behavior, which in turn affects the spread of disease. Adaptive network models that account for both epidemic and behavioral change have found oscillations, but in an extremely narrow region of the parameter space, which contrasts with intuition and available data. In this paper we propose a simple susceptible-infected-susceptible epidemic model on an adaptive network with time-delayed rewiring, and show that oscillatory solutions are now present in a wide region of the parameter space. Altering the transmission or rewiring rates reveals the presence of an endemic bubble—an enclosed region of the parameter space where oscillations are observed.

  5. ANTIGENAEMIA AS AN INDICATOR OF FILARIAL ENDEMICITY

    Directory of Open Access Journals (Sweden)

    F. Partono

    2012-09-01

    Full Text Available This is a report of 1 -year evaluation of chemotherapeutic intervention in an area of Indonesia endemic for lymphatic filariasis. Control measures were initiated in 1977 by parasite control, informal health educa­tion, and community participation at the village level, well in accord with the WHO-concept of health for all. Diethylcarbamazine (DEC was mass distributed in 1977 and 1988, and selectively distributed in 1978, 1979, 1981, and 1982 to those who were micro-filaraemic prior to DEC treatments, those with a history of adenoly mphangitis over the previous one year period, and to all new comers. In addition, each villager with acute symptoms of adenolymphangitis was immediately treated with a single course of 300 mg DEC for 10 days. No intervention measures were taken between 1982 to 1988, and no attempt was taken to control the vector or to restrict movement between controlled and uncontrolled areas during the whole studies. With these measures, the microfilaria (mf rate decreased from 30% to 0%, the adenolymphangitis rate from 46% to 11%, and the elephantiasis rate from 35% to 3%. The abatement of acute and chronic filarial symptoms over the study period and the disappearance of microfilaremia in the community are pointing towards the possibility of eradicating the partasite from the community. To test this hypothesis, serum samples were tested for circulating filarial antigen by a two-site antigen capture assay employing anti-phosphorylcholine monoclonal antibodies. There was a sharp fall in circulating antigenaemia, demonstrating that infection has either been eliminated from nearly all villagers, or that intensity of infection is now undetectably low. We feel that antigenaemia can be used as an indicator of filarial endemicity.

  6. Comparative phylogeography of endemic Azorean arthropods.

    Science.gov (United States)

    Parmakelis, Aristeidis; Rigal, François; Mourikis, Thanos; Balanika, Katerina; Terzopoulou, Sofia; Rego, Carla; Amorim, Isabel R; Crespo, Luís; Pereira, Fernando; Triantis, Kostas A; Whittaker, Robert J; Borges, Paulo A V

    2015-11-11

    For a remote oceanic archipelago of up to 8 Myr age, the Azores have a comparatively low level of endemism. We present an analysis of phylogeographic patterns of endemic Azorean island arthropods aimed at testing patterns of diversification in relation to the ontogeny of the archipelago, in order to distinguish between alternative models of evolutionary dynamics on islands. We collected individuals of six species (representing Araneae, Hemiptera and Coleoptera) from 16 forest fragments from 7 islands. Using three mtDNA markers, we analysed the distribution of genetic diversity within and between islands, inferred the differentiation time-frames and investigated the inter-island migration routes and colonization patterns. Each species exhibited very low levels of mtDNA divergence, both within and between islands. The two oldest islands were not strongly involved in the diffusion of genetic diversity within the archipelago. The most haplotype-rich islands varied according to species but the younger, central islands contributed the most to haplotype diversity. Colonization events both in concordance with and in contradiction to an inter-island progression rule were inferred, while a non-intuitive pattern of colonization from western to eastern islands was also inferred. The geological development of the Azores has followed a less tidy progression compared to classic hotspot archipelagos, and this is reflected in our findings. The study species appear to have been differentiating within the Azores for <2 Myr, a fraction of the apparent life span of the archipelago, which may indicate that extinction events linked to active volcanism have played an important role. Assuming that after each extinction event, colonization was initiated from a nearby island hosting derived haplotypes, the apparent age of species diversification in the archipelago would be moved closer to the present after each extinction-recolonization cycle. Exploiting these ideas, we propose a general

  7. Features of Acquired Immunity in Malaria Endemic Areas

    Indian Academy of Sciences (India)

    ... of Acquired Immunity in Malaria Endemic Areas. Adults (>15 years) do not suffer from the disease. Concomitant presence of low levels of P. falciparum in immune persons. This immunity is lost within 6-12 months if a person moves out of endemic area. Antibodies mediate protection for the asexual stages of P. falciparum.

  8. Endemic earthworms (Oligochaeta: Lumbricidae) of the Balkan Peninsula: a review.

    Science.gov (United States)

    Trakić, Tanja; Valchovski, Hristo; Stojanović, Mirjana

    2016-11-10

    A list of the endemic earthworms of the Balkan Peninsula is presented. Comprehensive information on the ecology, distribution on the Balkan Peninsula and zoogeographical type of all endemics is given. The list comprises 90 species and subspecies, belonging to 11 genera of the family Lumbricidae. The largest number of the Balkan endemic earthworms belongs to a narrow range group (63.3%). Broad range endemic species take part with 36.7%. Our study shows that the degree of endemism on the Balkan Peninsula is extremely high (about 40%) suggesting an important process of autochthonous speciation on the Balkan Peninsula. This appearance is attributable to relative isolation of the mountains compared to the lowlands within the context of paleoenvironmental changes.

  9. Endemism hotspots are linked to stable climatic refugia.

    Science.gov (United States)

    Harrison, Susan; Noss, Reed

    2017-01-01

    Centres of endemism have received much attention from evolutionists, biogeographers, ecologists and conservationists. Climatic stability is often cited as a major reason for the occurrences of these geographic concentrations of species which are not found anywhere else. The proposed linkage between endemism and climatic stability raises unanswered questions about the persistence of biodiversity during the present era of rapidly changing climate. The current status of evidence linking geographic centres of endemism to climatic stability over evolutionary time was examined. The following questions were asked. Do macroecological analyses support such an endemism-stability linkage? Do comparative studies find that endemic species display traits reflecting evolution in stable climates? Will centres of endemism in microrefugia or macrorefugia remain relatively stable and capable of supporting high biological diversity into the future? What are the implications of the endemism-stability linkage for conservation? Recent work using the concept of climate change velocity supports the classic idea that centres of endemism occur where past climatic fluctuations have been mild and where mountainous topography or favourable ocean currents contribute to creating refugia. Our knowledge of trait differences between narrow endemics and more widely distributed species remains highly incomplete. Current knowledge suggests that centres of endemism will remain relatively climatically buffered in the future, with the important caveat that absolute levels of climatic change and species losses in these regions may still be large. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Urinary iodine excretion in relation to goiter prevalence in households of goiter endemic and non endemic regions of Ethiopia

    International Nuclear Information System (INIS)

    Abuye, Chernet; Hailemariam, Bantiyrgu; Neka Tibeb, Hanna; Urga, Kelbesa; Woldegebriel, Zewidie

    1995-01-01

    A Survey of goiter prevalence, among population of five endemic and four non endemic regions of Ethiopia was carried out prior to the distribution of iodate d salt. urine samples were collected from 327 subjects selected by systematic random sampling from endemic and 276 taken as non endemic. The lowest mean urinary iodine excretion (UIE) value was recorded in Bure (22 micro gl/day) and the highest in Alemmaya (148 micro gl/day). The highest goiter rate ( percent TGR) was recorded in Sawla 55.6 %) and the lowest (0.6 %) in Yabello. Iodine content of drinking was in the range of 0.4 - 48.5 micro gl. Iodine content of water source was correlated positively ( r0.8399) with the mean of UIE and TGR, however, indicates that sites considered as non endemic seem to be affected by iodine deficiency. The study results urge the need for intervention in controlling Iodine Deficiency Disorders. 3 tab

  11. MEASURING SURFACE DEFORMATION IN GLACIER RETREATED AREAS BASED ON PS-INSAR – GELADANDONG GLACIER AS A CASE STUDY

    Directory of Open Access Journals (Sweden)

    B. Mohamadi

    2018-04-01

    Full Text Available Glaciers are retreating in many parts of the world as a result of global warming. Many researchers consider Qinghai-Tibetan Plateau as a reference for climate change by measuring glaciers retreat on the plateau. This retreat resulted in some topographic changes in retreated areas, and in some cases can lead to geohazards as landslides, and rock avalanches, which is known in glacier retreated areas as paraglacial slope failure (PSF. In this study, Geladandong biggest and main glacier mass was selected to estimate surface deformation on its glacier retreated areas and define potential future PSF based on PS-InSAR technique. 56 ascending and 49 descending images were used to fulfill this aim. Geladandong glacier retreated areas were defined based on the maximum extent of the glacier in the little ice age. Results revealed a general uplift in the glacier retreated areas with velocity less than 5mm/year. Obvious surface motion was revealed in seven parts surround glacier retreated areas with high relative velocity reached ±60mm/year in some parts. Four parts were considered as PSF potential motion, and two of them showed potential damage for the main road in the study area in case of rock avalanche into recent glacier lakes that could result in glacier lake outburst flooding heading directly to the road. Finally, further analysis and field investigations are needed to define the main reasons for different types of deformation and estimate future risks of these types of surface motion in the Qinghai-Tibetan Plateau.

  12. Hydrologic modeling of the Columbia Plateau basalts

    International Nuclear Information System (INIS)

    Dove, F.H.; Cole, C.R.; Bond, F.W.; Zimmerman, D.A.

    1982-09-01

    The Office of Nuclear Waste Isolation (ONWI) directed the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program to conduct a technology demonstration of current performance assessment techniques for the Department of Energy (DOE) as applied to a nuclear waste repository in the Columbia Plateau Basalts. Hypothetical repository coordinates were selected for an actual geographical setting on the Hanford Reservation in the state of Washington. Published hydrologic and geologic data used in the analyses were gathered in 1979 or earlier. The hydrologic simulation was divided into three major parts: (1) aquifer recharge calculations, (2) a regional hydrologic model, and (3) a local hydrologic model of the Pasco Basin. The presentation discusses the regional model. An estimate of the amount of water transmitted through the groundwater system was required to bound the transmissivity values and to estimate the transmissivity distributions for the deeper basalts. The multiple layer two-dimensional Variable Thickness Transient (VTT) code was selected as appropriate for the amount of data available and for the conditions existing in the regional systems. This model uses a finite difference formulation to represent the partial differential flow equation. The regional study area as defined for the VTT model was divided into 55 by 55 square pattern with each grid 5 kilometers on a side. The regional system was modeled as a held potential surface layer and two underlying basalt layers. The regional model established the boundary conditions for the hydrologic model the Pasco Basin

  13. Does the climate warming hiatus exist over the Tibetan Plateau?

    Science.gov (United States)

    Duan, Anmin; Xiao, Zhixiang

    2015-09-02

    The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China, and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998-2013 (0.25 °C decade(-1)), compared with that during 1980-1997 (0.21 °C decade(-1)). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud-radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998, and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud-radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau.

  14. Fate of Glaciers in the Tibetan Plateau by 2100

    Science.gov (United States)

    Duan, K.

    2017-12-01

    As the third polar on the Earth, the Tibetan plateau holds more than 40,000 glaciers which have experienced a rapid retreat in recent decades. The variability of equilibrium line altitude (ELA) indicates expansion and wastage of glacier directly. Here we simulated the ELA variability in the Tibetan Plateau based on a full surface energy and mass balance model. The simulation results are agreement with the observations. The ELAs have risen at a rate of 2-8m/a since 1970 throughout the Plateau, especially in the eastern Plateau where the ELAs have risen to or over the top altitude of glacier, indicating the glaciers are accelerating to melting over there. Two glaciers, XD glacier in the center of the Plateau and Qiyi glacier in the Qilian Mountain, are chosen to simulate its future ELA variability in the scenarios of RCP2.6, RCP4.5 and RCP 8.5 given by IPCC. The results show the ELAs will arrive to its maximum in around 2040 in RCP2.6, while the ELAs will be over the top altitude of glaciers in 2035-2045 in RCP4.5 and RCP8.5, suggesting the glaciers in the eastern Plateau will be melting until the disappear of the glaciers by the end of 2100.

  15. Costs of Illness Due to Endemic Cholera

    Science.gov (United States)

    Poulos, C.; Riewpaiboon, A.; Stewart, J.F.; Clemens, J.; Guh, S.; Agtini, M.; Sur, D.; Islam, Z.; Lucas, M.; Whittington, D.

    2013-01-01

    Summary Economic analyses of cholera immunization programmes require estimates of the costs of cholera. The Diseases of the Most Impoverished programme measured the public, provider, and patient costs of culture-confirmed cholera in four study sites with endemic cholera using a combination of hospital- and community-based studies. Families with culture-proven cases were surveyed at home 7 and 14 days after confirmation of illness. Public costs were measured at local health facilities using a micro-costing methodology. Hospital-based studies found that the costs of severe cholera were USD 32 and 47 in Matlab and Beira. Community-based studies in North Jakarta and Kolkata found that cholera cases cost between USD 28 and USD 206, depending on hospitalization. Patient costs of illness as a percentage of average monthly income were 21% and 65% for hospitalized cases in Kolkata and North Jakarta, respectively. This burden on families is not captured by studies that adopt a provider perspective. PMID:21554781

  16. Endemic pemphigus over a century: Part II.

    Science.gov (United States)

    Abréu-Vélez, Ana María; Roselino, Ana Maria; Howard, Michael S; Reason, Iara J de Messias

    2010-03-01

    Endemic pemphigus foliaceus (EPF) is an autoimmune disease, classically occurring in a restricted geographic area. Foci of EPF have been described in several Central and South American countries, often affecting young people and Amerindians, with some female predilection. Although most American EPF cases have been documented in Brazil, cases have been reported in Peru, Paraguay, El Salvador and Venezuela. An additional variant of EPF has been described in El Bagre, Colombia, (El Bagre-EPF) affecting older men and a few post-menopausal females. Finally, one additional type of EPF has been described in nomadic tribes affecting females of child bearing age in Tunisia, Africa. The main aim of this review is to summarize current knowledge about autoantigens, and immunologic and genetic studies in EPF. We utilized a retrospective review of the literature, aiming to compile and compare the multiple geographic foci of EPF. The primary autoantigens in EPF are still considered to be desmogleins in the case of the Tunisian and all American cases, in contradistinction to plakins and desmogleins in El Bagre-EPF. Although several autoantigens are been suggested, their biochemical nature needs further elucidation. Current knowledge still supports the concept that an antibody mediated immune response represents the principal pathophysiology in all variants of EPF. A strong genetic susceptibility appears to contribute to disease development in several people affected by these diseases; however, no specific genes have been confirmed at present. We conclude that further investigation is necessary to define these disorders immunologically and genetically.

  17. Updated Global Burden of Cholera in Endemic Countries

    Science.gov (United States)

    Ali, Mohammad; Nelson, Allyson R.; Lopez, Anna Lena; Sack, David A.

    2015-01-01

    Background The global burden of cholera is largely unknown because the majority of cases are not reported. The low reporting can be attributed to limited capacity of epidemiological surveillance and laboratories, as well as social, political, and economic disincentives for reporting. We previously estimated 2.8 million cases and 91,000 deaths annually due to cholera in 51 endemic countries. A major limitation in our previous estimate was that the endemic and non-endemic countries were defined based on the countries’ reported cholera cases. We overcame the limitation with the use of a spatial modelling technique in defining endemic countries, and accordingly updated the estimates of the global burden of cholera. Methods/Principal Findings Countries were classified as cholera endemic, cholera non-endemic, or cholera-free based on whether a spatial regression model predicted an incidence rate over a certain threshold in at least three of five years (2008-2012). The at-risk populations were calculated for each country based on the percent of the country without sustainable access to improved sanitation facilities. Incidence rates from population-based published studies were used to calculate the estimated annual number of cases in endemic countries. The number of annual cholera deaths was calculated using inverse variance-weighted average case-fatality rate (CFRs) from literature-based CFR estimates. We found that approximately 1.3 billion people are at risk for cholera in endemic countries. An estimated 2.86 million cholera cases (uncertainty range: 1.3m-4.0m) occur annually in endemic countries. Among these cases, there are an estimated 95,000 deaths (uncertainty range: 21,000-143,000). Conclusion/Significance The global burden of cholera remains high. Sub-Saharan Africa accounts for the majority of this burden. Our findings can inform programmatic decision-making for cholera control. PMID:26043000

  18. [Safety threshold of fluorine in endemic fluorosis regions in China].

    Science.gov (United States)

    Li, Yonghua; Wang, Wuyi; Hou, Shaofan

    2002-07-01

    Four endemic fluorosis regions in China and their environmental epidemiological characteristics were summarized in this paper. It shows that the epidemiology of endemic fluorosis is closely related to geochemical parameters of local environment. The food-web and dose-effect relationship of fluoride from environment to human body in different types of endemic fluorosis regions were studied. And the safety threshold of fluoride in different regions was determined. The results have provided a scientific basis for environmental risk assessment of fluoride in China.

  19. Variations in deep-sea hydrothermal vent communities on the Mid-Atlantic Ridge near the Azores plateau

    Science.gov (United States)

    Desbruyères, D.; Biscoito, M.; Caprais, J.-C.; Colaço, A.; Comtet, T.; Crassous, P.; Fouquet, Y.; Khripounoff, A.; Le Bris, N.; Olu, K.; Riso, R.; Sarradin, P.-M.; Segonzac, M.; Vangriesheim, A.

    2001-05-01

    Near the Azores Triple Junction as the Azores Plateau is approached, the ridge axis becomes shallower; its depth decreases from ca. 2400 m in the R AINBOW vent field (36°13'N) to ca. 850 m in the M ENEZ G WEN vent field (37°35'N). In this area, extensive mussel beds of the mytilid Bathymodiolus azoricus dominate the hydrothermal vent fauna, along with populations of three shrimps ( Rimicaris exoculata, Mirocaris fortunata and Chorocaris chacei). The main physical and chemical characteristics of the vent habitat were studied by discrete sampling, in situ analysis and sediment trap moorings. The vent fauna is distributed along a variable band where the vent fluids and seawater mix, with R. exoculata living in the most concentrated areas and Bathymodiolus azoricus in the most diluted zones. Various non-endemic species live at the border of the vent field. The variations observed in structure and composition of the communities along the depth gradient are most likely due to changes in vent fluid toxicity (metallic and sulphide content) and suspended mineral particles, which render the fluids harsher for species living there. The main faunal differences observed between L UCKY S TRIKE and M ENEZ G WEN hydrothermal fields are due to an impoverishment in the hydrothermal endemic species and to the penetration of bathyal species. The comparison of the three studied vent fields suggests the existence of a succession of several biogeographic islands rather than a single province.

  20. Glacial survival east and west of the 'Mekong-Salween Divide' in the Himalaya-Hengduan Mountains region as revealed by AFLPs and cpDNA sequence variation in Sinopodophyllum hexandrum (Berberidaceae).

    Science.gov (United States)

    Li, Yong; Zhai, Sheng-Nan; Qiu, Ying-Xiong; Guo, Yan-Ping; Ge, Xue-Jun; Comes, Hans Peter

    2011-05-01

    Molecular phylogeographic studies have recently begun to elucidate how plant species from the Qinghai-Tibetan Plateau (QTP) and adjacent regions responded to the Quaternary climatic oscillations. In this regard, however, far less attention has been paid to the southern and south-eastern declivities of the QTP, i.e. the Himalaya-Hengduan Mountains (HHM) region. Here, we report a survey of amplified fragment length polymorphisms (AFLPs) and chloroplast DNA (cpDNA) sequence variation in the HHM endemic Sinopodophyllum hexandrum, a highly selfing alpine perennial herb with mainly gravity-dispersed berries (105 individuals, 19 localities). We specifically aimed to test a vicariant evolutionary hypothesis across the 'Mekong-Salween Divide', a known biogeographic and phytogeographic boundary of north-to-south trending river valleys separating the East Himalayas and Hengduan Mts. Both cpDNA and AFLPs identified two divergent phylogroups largely congruent with these mountain ranges. There was no genetic depauperation in the more strongly glaciated East Himalayas (AFLPs: H(E)=0.031; cpDNA: h(S)=0.133) compared to the mainly ice-free Hengduan Mts. (AFLPs: H(E)=0.037; cpDNA: h(S)=0.082), while population differentiation was consistently higher in the former region (AFLPs: Φ(ST)=0.522 vs. 0.312; cpDNA: Φ(ST)=0.785 vs. 0.417). Our results suggest that East Himalayan and Hengduan populations of S. hexandrum were once fragmented, persisted in situ during glacials in both areas, and have not merged again, except for a major instance of inter-lineage chloroplast capture identified at the MSD boundary. Our coalescent time estimate for all cpDNA haplotypes (c. 0.37-0.48 mya), together with paleogeological evidence, strongly rejects paleo-drainage formation as a mechanism underlying allopatric fragmentation, whereas mountain glaciers following the ridges of the MSD during glacials (and possible interglacials) could have been responsible. This study thus indicates an important role

  1. The complete chloroplast genome sequence of Gentiana lawrencei var. farreri (Gentianaceae) and comparative analysis with its congeneric species.

    Science.gov (United States)

    Fu, Peng-Cheng; Zhang, Yan-Zhao; Geng, Hui-Min; Chen, Shi-Long

    2016-01-01

    The chloroplast (cp) genome is useful in plant systematics, genetic diversity analysis, molecular identification and divergence dating. The genus Gentiana contains 362 species, but there are only two valuable complete cp genomes. The purpose of this study is to report the characterization of complete cp genome of G. lawrencei var. farreri , which is endemic to the Qinghai-Tibetan Plateau (QTP). Using high throughput sequencing technology, we got the complete nucleotide sequence of the G. lawrencei var. farreri cp genome. The comparison analysis including genome difference and gene divergence was performed with its congeneric species G. straminea . The simple sequence repeats (SSRs) and phylogenetics were studied as well. The cp genome of G. lawrencei var. farreri is a circular molecule of 138,750 bp, containing a pair of 24,653 bp inverted repeats which are separated by small and large single-copy regions of 11,365 and 78,082 bp, respectively. The cp genome contains 130 known genes, including 85 protein coding genes (PCGs), eight ribosomal RNA genes and 37 tRNA genes. Comparative analyses indicated that G. lawrencei var. farreri is 10,241 bp shorter than its congeneric species G. straminea. Four large gaps were detected that are responsible for 85% of the total sequence loss. Further detailed analyses revealed that 10 PCGs were included in the four gaps that encode nine NADH dehydrogenase subunits. The cp gene content, order and orientation are similar to those of its congeneric species, but with some variation among the PCGs. Three genes, ndhB , ndhF and clpP , have high nonsynonymous to synonymous values. There are 34 SSRs in the G. lawrencei var. farreri cp genome, of which 25 are mononucleotide repeats: no dinucleotide repeats were detected. Comparison with the G. straminea cp genome indicated that five SSRs have length polymorphisms and 23 SSRs are species-specific. The phylogenetic analysis of 48 PCGs from 12 Gentianales taxa cp genomes clearly identified

  2. Plant molecular phylogeography in China and adjacent regions: Tracing the genetic imprints of Quaternary climate and environmental change in the world's most diverse temperate flora.

    Science.gov (United States)

    Qiu, Ying-Xiong; Fu, Cheng-Xing; Comes, Hans Peter

    2011-04-01

    The Sino-Japanese Floristic Region (SJFR) of East Asia harbors the most diverse of the world's temperate flora, and was the most important glacial refuge for its Tertiary representatives ('relics') throughout Quaternary ice-age cycles. A steadily increasing number of phylogeographic studies in the SJFR of mainland China and adjacent areas, including the Qinghai-Tibetan-Plateau (QTP) and Sino-Himalayan region, have documented the population histories of temperate plant species in these regions. Here we review this current literature that challenges the oft-stated view of the SJFR as a glacial sanctuary for temperate plants, instead revealing profound effects of Quaternary changes in climate, topography, and/or sea level on the current genetic structure of such organisms. There are three recurrent phylogeographic scenarios identified by different case studies that broadly agree with longstanding biogeographic or palaeo-ecological hypotheses: (i) postglacial re-colonization of the QTP from (south-)eastern glacial refugia; (ii) population isolation and endemic species formation in Southwest China due to tectonic shifts and river course dynamics; and (iii) long-term isolation and species survival in multiple localized refugia of (warm-)temperate deciduous forest habitats in subtropical (Central/East/South) China. However, in four additional instances, phylogeographic findings seem to conflict with a priori predictions raised by palaeo-data, suggesting instead: (iv) glacial in situ survival of some hardy alpine herbs and forest trees on the QTP platform itself; (v) long-term refugial isolation of (warm-)temperate evergreen taxa in subtropical China; (vi) 'cryptic' glacial survival of (cool-)temperate deciduous forest trees in North China; and (vii) unexpectedly deep (Late Tertiary/early-to-mid Pleistocene) allopatric-vicariant differentiation of disjunct lineages in the East China-Japan-Korea region due to past sea transgressions. We discuss these and other consequences

  3. The Colorado Plateau II: biophysical, socioeconomic, and cultural research

    Science.gov (United States)

    Mattson, David J.; van Riper, Charles

    2005-01-01

    The publication of The Colorado Plateau: Cultural, Biological, and Physical Research in 2004 marked a timely summation of current research in the Four Corners states. This new volume, derived from the seventh Biennial Conference on the Colorado Plateau in 2003, complements the previous book by focusing on the integration of science into resource management issues. The 32 chapters range in content from measuring human impacts on cultural resources, through grazing and the wildland-urban interface issues, to parameters of climate change on the Plateau. The book also introduces economic perspectives by considering shifting patterns and regional disparities in the Colorado Plateau economy. A series of chapters on mountain lions explores the human-wildland interface. These chapters deal with the entire spectrum of challenges associated with managing this large mammal species in Arizona and on the Colorado Plateau, conveying a wealth of timely information of interest to wildlife managers and enthusiasts. Another provocative set of chapters on biophysical resources explores the management of forest restoration, from the micro scale all the way up to large-scale GIS analyses of ponderosa pine ecosystems on the Colorado Plateau. Given recent concerns for forest health in the wake of fires, severe drought, and bark-beetle infestation, these chapters will prove enlightening for forest service, park service, and land management professionals at both the federal and state level, as well as general readers interested in how forest management practices will ultimately affect their recreation activities. With broad coverage that touches on topics as diverse as movement patterns of rattlesnakes, calculating watersheds, and rescuing looted rockshelters, this volume stands as a compendium of cutting-edge research on the Colorado Plateau that offers a wealth of insights for many scholars.

  4. Endemic infrared divergences in QED3 at finite temperature

    International Nuclear Information System (INIS)

    Lo, Pok Man; Swanson, Eric S.

    2011-01-01

    We demonstrate that massless QED in three dimensions contains endemic infrared divergences. It is argued that these divergences do not affect observables; furthermore, it is possible to choose a gauge that renders the theory finite.

  5. Chlamydia trachomatis serovars of endemic trachoma had been ...

    African Journals Online (AJOL)

    Journal of Applied Sciences and Environmental Management ... The serovars that we identified from Japanese infants and pregnant women ... Once Japan was thought to be belong to an endemic area of trachoma as other Asian countries.

  6. The dynamics of endemic malaria in populations of varying size

    International Nuclear Information System (INIS)

    Ngwa, G.A.

    2001-10-01

    A mathematical model for endemic malaria involving variable human and mosquito populations is analysed. A threshold parameter R 0 exists and the disease can persist if and only if R 0 exceeds 1. R 0 is seen to be a generalisation of the basic reproduction ratio associated with the Ross-Macdonald model for malaria transmission. The disease free equilibrium always exist and is globally stable when R 0 is below 1. A perturbation analysis is used to approximate the endemic equilibrium in the important case where the disease related death rate is nonzero. A diffusion approximation is used to approximate the quasi-stationary distribution of the associated stochastic model. Numerical simulations show that when R 0 is distinctly greater than 1, the endemic deterministic equilibrium is globally stable. Furthermore, in quasi-stationarity, the stochastic process undergoes oscillations about a mean population whose size can be approximated by the stable endemic deterministic equilibrium. (author)

  7. Spatial distribution of Madeira Island Laurisilva endemic spiders (Arachnida: Araneae)

    Science.gov (United States)

    2014-01-01

    Abstract Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported – Ceratinopsis n. sp. and Theridion n. sp. – and the first records of Poeciloneta variegata (Blackwall, 1841) and Tetragnatha intermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island. PMID:24855443

  8. An Investigation on the antimicrobial activity of some endemic plant ...

    African Journals Online (AJOL)

    SERVER

    2008-01-04

    Jan 4, 2008 ... Key words: Antimicrobial activity, endemic plants, plant extract. INTRODUCTION ..... The essential oil of A. balsamea was found to be inactive against E. ... Origanum solymicum and Origanum bilgeri from Turkey. Afr. J. Trad.

  9. isoenzyme analysis of five endemic and one widespread kniphofia ...

    African Journals Online (AJOL)

    Preferred Customer

    ISOENZYME ANALYSIS OF FIVE ENDEMIC AND ONE WIDESPREAD ... plants. The over all mean inbreeding coefficient (F) was positive indicating slight deficiency in the number of ...... populations, indicates rather recent speciation.

  10. A world malaria map: Plasmodium falciparum endemicity in 2007.

    Directory of Open Access Journals (Sweden)

    Simon I Hay

    2009-03-01

    Full Text Available Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007.A total of 8,938 P. falciparum parasite rate (PfPR surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2-10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia, 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+, and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2-10 5 to or = 40% areas. High endemicity was widespread in the Africa+ region, where 0.35 billion people are at this level of risk. Most of the rest live at intermediate risk (0.20 billion, with a smaller number (0.11 billion at low stable risk.High levels of P. falciparum malaria endemicity are common in Africa. Uniformly low endemic levels are

  11. A world malaria map: Plasmodium falciparum endemicity in 2007.

    Science.gov (United States)

    Hay, Simon I; Guerra, Carlos A; Gething, Peter W; Patil, Anand P; Tatem, Andrew J; Noor, Abdisalan M; Kabaria, Caroline W; Manh, Bui H; Elyazar, Iqbal R F; Brooker, Simon; Smith, David L; Moyeed, Rana A; Snow, Robert W

    2009-03-24

    Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007. A total of 8,938 P. falciparum parasite rate (PfPR) surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2-10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia), 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+), and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2-10 5 to or = 40%) areas. High endemicity was widespread in the Africa+ region, where 0.35 billion people are at this level of risk. Most of the rest live at intermediate risk (0.20 billion), with a smaller number (0.11 billion) at low stable risk. High levels of P. falciparum malaria endemicity are common in Africa. Uniformly low endemic levels are found in the

  12. Visualizing ecological sensitivity assessment of Huangnan, in the Three-river Region, China, based on GIS

    Science.gov (United States)

    Meng, Xia; Guo, Luo

    2017-07-01

    Huangnan Tibetan Autonomous Prefecture is located in the three-river source region (the TRSR) in the Qinghai-Tibetan Plateau, China, which is characterized with ecological sensitivity and vulnerability. In the paper, we integrated remote sensing images, field investigation and social-economic data , and with the help of analytic hierarchy process (AHP) and comprehensive index methods, a sensitivity assessment system was built to calculate ecological sensitivity scores and assign levels for the study area. Results show that: areas which are moderately or even highly ecologically sensitive account for 54.02%, distributed in south, north and northeast of study area and those that have most apparent ecological sensitivity are mainly located in Zeekog, northwest of Huangnan while other counties enjoy relatively lower sensitivity. The results will facilitate future region management and planning for decision-makers.

  13. Endangered, rare and endemic medicinal plants of the Kopetdag

    OpenAIRE

    AKMURADOV ALLAMURAD; SHAIYMOV BABAGULY; HALMEDOV BAZAR; YAKUBOV ATABEG; HALLIYEVA GULYAIYM

    2016-01-01

    The article presents some information of the place of growing of the endangered, rare and endemic medicinal plants of the Kopetdag. A monitoring has been carried out and the bioecological peculiarities, resource characteristics and modern state of the natural population of the most important species have been studied. Some scientifically based ways of protection and introduction into culture have been worked out to preserve the endangered, rare and endemic medicinal plants of the region.

  14. Endemic harvestmen and spiders of Austria (Arachnida: Opiliones, Araneae

    Directory of Open Access Journals (Sweden)

    Komposch, Christian

    2011-01-01

    Full Text Available A comprehensive overview of plant, fungus and animal species of Austria revealed a total of 748 endemic and subendemic species, including, 11 harvestman and 46 spider species. Altogether two endemic harvestmen (Nemastoma bidentatum relictum, Nemastoma schuelleri and 8 endemic spiders (Abacoproeces molestus, Collinsia (caliginosa nemenziana, Mughiphantes severus, Mughiphantes styriacus, Pelecopsis alpica, Scotophaeus nanus, Troglohyphantes novicordis, Troglohyphantes tauriscus, beside 9 subendemic harvestman and 38 subendemic spider species have been recorded from Austria. Hot-spots of endemism in the Eastern Alps are the north-eastern (Ennstaler Alps and southern Calcareous Alps (Karawanken, Karnische Alps and the Central Alps (Hohe Tauern, Gurktaler Alps, Ötztaler and Stubaier Alps. Most of the endemic arachnid species occur from the nival down to the montane zone. Important habitats are rocky areas, caves and woodlands. High absolute numbers and percentages of endemics can be found within the harvestman families Cladonychiidae, Ischyropsalididae and Nemastomatidae and in the spider genera Lepthyphantes s. l. and Troglohyphantes. The conservation status of these highly endangered taxa – 85 % of the spider species and 100 % of the harvestman taxa are endangered in Austria – is poor.

  15. Hexabromocyclododecane in alpine fish from the Tibetan Plateau, China

    International Nuclear Information System (INIS)

    Zhu, Nali; Fu, Jianjie; Gao, Yan; Ssebugere, Patrick; Wang, Yawei; Jiang, Guibin

    2013-01-01

    Hexabromocyclododecanes (HBCDs) has just been listed into Stockholm Convention as a persistent organic pollutant recently. This paper studied the HBCDs in 79 wild fish from high mountain lakes and rivers of the Tibetan Plateau. The ∑HBCDs in fish muscles ranged from non detectable levels to 13.7 ng/g lipid weight (lw) (mean value of 2.12 ng/g lw) with a high detection frequency of 65.8%. α-HBCD dominated among the isomers and accounted for 78.2% of the total burden. Concentrations of ∑HBCDs in the fish were significantly correlated with the lipid content . A decreasing trend was observed between α-HBCD and trophic level. Positive correlation was also noted between the HBCD levels in fish from lakes and the annual precipitation, and this implied the long-range atmospheric transport of HBCDs to the Tibet Plateau. This was the first work to widely explore HBCDs contamination in the aquatic ecosystems of the Tibetan Plateau. -- Highlights: •HBCDs were ubiquitous in fish of the Tibetan Plateau. •α-HBCD showed a negative correlation with TL in the Lhasa River aquatic food web. •Concentrations of ∑HBCD were significantly correlated with lipid contents of fish. -- HBCD was ubiquitous in fish of the Tibetan Plateau, and its concentration was significantly correlated with lipid content

  16. Fraturas do planalto tibial Tibial plateau fractures

    Directory of Open Access Journals (Sweden)

    Maurício Kfuri Júnior

    2009-01-01

    Full Text Available As fraturas do planalto tibial são lesões articulares cujos princípios de tratamento envolvem a redução anatômica da superfície articular e a restauração funcional do eixo mecânico do membro inferior. Contribuem para a tomada de decisões no tratamento dessas fraturas o perfil do paciente, as condições do envelope de tecidos moles, a existência de outros traumatismos associados e a infraestrutura disponível para abordagens cirúrgicas. Para as fraturas de alta energia, o tratamento estagiado, seguindo o princípio do controle de danos, tem como prioridade a manutenção do alinhamento do membro enquanto se aguarda a resolução das más condições de tecidos moles. Já nos traumas de baixa energia, desde que os tecidos moles não sejam um fator adverso, o tratamento deve ser realizado em tempo único, com osteossíntese definitiva. Fixação estável e movimento precoce são variáveis diretamente relacionadas com os melhores prognósticos. Desenvolvimentos recentes, como os implantes com estabilidade angular, substitutos ósseos e imagens tridimensionais para controle intraoperatório, deverão contribuir para cirurgias menos invasivas e melhores resultados.Tibial plateau fractures are joint lesions that require anatomical reduction of joint surface and functional restoration of mechanical axis of a lower limb. Patient profile, soft tissue conditions, presence of associated injuries and the available infrastructure for the treatment all contribute to the decision making about the best treatment for these fractures. High-energy fractures are usually approached in a staged manner respecting the principle of damage control, and are primarily targeted to maintain limb alignment while the resolution unfavorable soft tissue conditions is pending. Low-energy trauma can be managed on a single-stage basis, provided soft tissues are not an adverse factor, with open reduction and internal f-ixation. Stable fixation and early painless joint

  17. Phenotype- and SSR-Based Estimates of Genetic Variation between and within Two Important Elymus Species in Western and Northern China

    Directory of Open Access Journals (Sweden)

    Zongyu Zhang

    2018-03-01

    Full Text Available Elymus nutans and Elymus sibiricus are two important perennial forage grasses of the genus Elymus, widely distributed in high altitude regions of Western and Northern China, especially on the Qinghai-Tibetan Plateau. Information on phenotypic and genetic diversity is limited, but necessary for Elymus germplasm collection, conservation, and utilization. In the present study, the phenotypic and genetic differentiation of 73 accessions of the two species were evaluated using 15 phenotypic traits and 40 expressed sequence tag derived simple sequence repeat markers (EST-SSRs. The results showed that only 7.23% phenotypic differentiation (Pst existed between the two Elymus species based on fifteen quantitative traits. Principal component analysis (PCA revealed that leaf traits, spike traits, and some seed traits were dominant factors in phenotypic variation. Moreover, 396 (97.8% and 331 (87.1% polymorphic bands were generated from 40 EST-SSR primers, suggesting high levels of genetic diversity for the two species. The highest genetic diversity was found in the Northeastern Qinghai-Tibetan Plateau groups. Clustering analysis based on molecular data showed that most accessions of each Elymus species tended to group together. Similar results were described by principal coordinates analysis (PCoA and structure analysis. The molecular variance analysis (AMOVA revealed that 81.47% and 89.32% variation existed within the geographical groups for the two species, respectively. Pearson’s correlation analyses showed a strong positive correlation between Nei’s genetic diversity and annual mean temperature. These results could facilitate Elymus germplasm collection, conservation, and future breeding.

  18. Extensive genetic divergence among Diptychus maculatus populations in northwest China

    Science.gov (United States)

    Meng, Wei; Yang, Tianyan; Hai, Sa; Ma, Yanwu; Cai, Lingang; Ma, Xufa; Gao, Tianxiang; Guo, Yan

    2015-05-01

    D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ili River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure of D. maculates, four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations, only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined, the haplotype diversity ( h) was 0.904 8±0.012 6, nucleotide diversity (π) was 0.027 9±0.013 9, and the average number of pairwise nucleotide differences ( k) was 15.878 3±7.139 1. The analysis of molecular variance (AMOVA) showed that 86.31% of the total genetic variation was apportioned among populations, and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. F st statistical test indicated that all populations were significantly divergent from each other ( P<0.01). The largest F st value was between Yurungkash River population and Muzat River population, while the smallest F st value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China.

  19. Evolutionary dynamics of the Pgk1 gene in the polyploid genus Kengyilia (Triticeae: Poaceae and its diploid relatives.

    Directory of Open Access Journals (Sweden)

    Xing Fan

    Full Text Available The level and pattern of nucleotide variation in duplicate gene provide important information on the evolutionary history of polyploids and divergent process between homoeologous loci within lineages. Kengyilia is a group of allohexaploid species with the StYP genomic constitutions in the wheat tribe. To investigate the evolutionary dynamics of the Pgk1 gene in Kengyilia and its diploid relatives, three copies of Pgk1 homoeologues were isolated from all sampled hexaploid Kengyilia species and analyzed with the Pgk1 sequences from 47 diploid taxa representing 18 basic genomes in Triticeae. Sequence diversity patterns and genealogical analysis suggested that (1 Kengyilia species from the Central Asia and the Qinghai-Tibetan plateau have independent origins with geographically differentiated P genome donors and diverged levels of nucleotide diversity at Pgk1 locus; (2 a relatively long-time sweep event has allowed the Pgk1 gene within Agropyron to adapt to cold climate triggered by the recent uplifts of the Qinghai-Tibetan Plateau; (3 sweep event and population expansion might result in the difference in the d(N/d(S value of the Pgk1 gene in allopatric Agropyron populations, and this difference may be genetically transmitted to Kengyilia lineages via independent polyploidization events; (4 an 83 bp MITE element insertion has shaped the Pgk1 loci in the P genome lineage with different geographical regions; (5 the St and P genomes in Kengyilia were donated by Pseudoroegneria and Agropyron, respectively, and the Y genome is closely related to the Xp genome of Peridictyon sanctum. The interplay of evolutionary forces involving diverged natural selection, population expansion, and transposable events in geographically differentiated P genome donors could attribute to geographical differentiation of Kengyilia species via independent origins.

  20. Genetic Diversity and Phylogenetic Evolution of Tibetan Sheep Based on mtDNA D-Loop Sequences.

    Directory of Open Access Journals (Sweden)

    Jianbin Liu

    Full Text Available The molecular and population genetic evidence of the phylogenetic status of the Tibetan sheep (Ovis aries is not well understood, and little is known about this species' genetic diversity. This knowledge gap is partly due to the difficulty of sample collection. This is the first work to address this question. Here, the genetic diversity and phylogenetic relationship of 636 individual Tibetan sheep from fifteen populations were assessed using 642 complete sequences of the mitochondrial DNA D-loop. Samples were collected from the Qinghai-Tibetan Plateau area in China, and reference data were obtained from the six reference breed sequences available in GenBank. The length of the sequences varied considerably, between 1031 and 1259 bp. The haplotype diversity and nucleotide diversity were 0.992±0.010 and 0.019±0.001, respectively. The average number of nucleotide differences was 19.635. The mean nucleotide composition of the 350 haplotypes was 32.961% A, 29.708% T, 22.892% C, 14.439% G, 62.669% A+T, and 37.331% G+C. Phylogenetic analysis showed that all four previously defined haplogroups (A, B, C, and D were found in the 636 individuals of the fifteen Tibetan sheep populations but that only the D haplogroup was found in Linzhou sheep. Further, the clustering analysis divided the fifteen Tibetan sheep populations into at least two clusters. The estimation of the demographic parameters from the mismatch analyses showed that haplogroups A, B, and C had at least one demographic expansion in Tibetan sheep. These results contribute to the knowledge of Tibetan sheep populations and will help inform future conservation programs about the Tibetan sheep native to the Qinghai-Tibetan Plateau.

  1. Teaching Rayleigh–Plateau instabilities in the laboratory

    International Nuclear Information System (INIS)

    Fragkopoulos, A A; Ellis, P W; Fernandez-Nieves, A

    2015-01-01

    The breakup of a liquid jet into spherical droplets via the Rayleigh–Plateau instability is a common and fundamental part of fluid mechanics. However, teaching this instability in a laboratory setting is challenging, requiring sophisticated methods to generate and study the jet dynamics. Recently, toroidal droplets were shown to break into one or more spherical droplets in the thin-drop limit via the Rayleigh–Plateau instability. We propose a simple experimental setup to generate toroidal droplets that break up on the order of tens of seconds, allowing for easy video capture using a basic CCD camera. With this setup, it is possible to quantify the Rayleigh–Plateau instability in a pedagogical laboratory setting. In addition, the role of curvature on jet breakup can be explored using thick toroidal droplets. We envision this setup as a powerful teaching tool for one of the most fundamental fluid dynamics processes. (paper)

  2. Fukushima Nuclear Accident Recorded in Tibetan Plateau Snow Pits

    Science.gov (United States)

    Wang, Ninglian; Wu, Xiaobo; Kehrwald, Natalie; Li, Zhen; Li, Quanlian; Jiang, Xi; Pu, Jianchen

    2015-01-01

    The β radioactivity of snow-pit samples collected in the spring of 2011 on four Tibetan Plateau glaciers demonstrate a remarkable peak in each snow pit profile, with peaks about ten to tens of times higher than background levels. The timing of these peaks suggests that the high radioactivity resulted from the Fukushima nuclear accident that occurred on March 11, 2011 in eastern Japan. Fallout monitoring studies demonstrate that this radioactive material was transported by the westerlies across the middle latitudes of the Northern Hemisphere. The depth of the peak β radioactivity in each snow pit compared with observational precipitation records, suggests that the radioactive fallout reached the Tibetan Plateau and was deposited on glacier surfaces in late March 2011, or approximately 20 days after the nuclear accident. The radioactive fallout existed in the atmosphere over the Tibetan Plateau for about one month. PMID:25658094

  3. FOLIAR ANATOMY OF ENDEMICS SPECIES OF Cattleya (ORCHIDACEAE ENDEMIC FROM GUIANA SHIELD

    Directory of Open Access Journals (Sweden)

    Graciene Tomaz Carneiro

    2017-03-01

    Full Text Available The main goal of this study was characterize the leaf's anatomical aspects of Cattleya jenmanii Rolfe and e C. lawrenceana Rchb. f., describing its anatomical structures in order to increase the knowledge of this endemic species from the region of the Guiana Shield. Besides, it also intended to identify foliar characters to assist in the anatomical comparison of these species. For anatomical study, the material was fixed in FAA and to make the slides we used the usual cut freehand technique and stained with double staining from Safranin with Blue Astra (Safrablau. C. jenmanii and C. lawrenceana has fleshy leaves covered with a thick cuticle. The mesophyll presented dorsiventral with collateral vascular bundles. A large number of bundles of smaller caliber fibers are distributed in the mesophyll poles. Only the presence of a subepidermal layer of fibers differed C. lawrenceana from C. jenmanii. Keyword: Roraima; Guiana Shield; Cattleya; Amazon Basin.

  4. Mineralogy and geochemistry of vanadium in the Colorado Plateau

    Science.gov (United States)

    Weeks, A.D.

    1961-01-01

    The chief domestic source of vanadium is uraniferous sandstone in the Colorado Plateau. Vanadium is 3-, 4-, or 5-valent in nature and, as oxides or combined with other elements, it forms more than 40 minerals in the Plateau ores. These ores have been studied with regard to the relative amounts of vanadium silicates and oxide-vanadates, uranium-vanadium ratios, the progressive oxidation of black low-valent ores to high-valent carnotite-type ores, and theories of origin. ?? 1961.

  5. Does the climate warming hiatus exist over the Tibetan Plateau?

    OpenAIRE

    Anmin Duan; Zhixiang Xiao

    2015-01-01

    The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China, and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998–2013 (0.25 °C decade−1), compared with that during 1980–1997 (0.21 °C decade−1). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud–ra...

  6. Late-Glacial radiocarbon- and palynostratigraphy in the Swiss Plateau

    International Nuclear Information System (INIS)

    Ammann, B.; Lotter, A.F.

    1989-01-01

    A detailed Late-Glacial radiocarbon stratigraphy for the Swiss Plateau has been established on the basis of over 90 accelerator 14 C dates on terrestrial plant macrofossils. A comparison of the radiocarbon ages derived from terrestrial, telmatic and limnic material at different sites on the Swiss Plateau yields a proposal for modifying the zonation system of Welten for the Late-Glacial. By retaining the limits of chronozones and by refining the palynostratigraphic criteria for the limits of biozones, a separation between chrono- and biozonation at the beginning of the Boelling and the Younger Dryas becomes obvious. 54 refs

  7. Plateau onset for correlation dimension: When does it occur?

    International Nuclear Information System (INIS)

    Ding, M.; Grebogi, C.; Ott, E.; Sauer, T.; Yorke, J.A.

    1993-01-01

    Chaotic experimental systems are often investigated using delay coordinates. Estimated values of the correlation dimension in delay coordinate space typically increase with the number of delays and eventually reach a plateau (on which the dimension estimate is relatively constant) whose value is commonly taken as an estimate of the correlation dimension D 2 of the underlying chaotic attractor. We report a rigorous result which implies that, for long enough data sets, the plateau begins when the number of delay coordinates first exceeds D 2 . Numerical experiments are presented. We also discuss how lack of sufficient data can produce results that seem to be inconsistent with the theoretical prediction

  8. The endemic plants of Micronesia: a geographical checklist and commentary

    Directory of Open Access Journals (Sweden)

    Lorence, D.H.

    2012-05-01

    Full Text Available The Micronesia-Polynesia bioregion is recognized as a global biodiversity hotspot. However, until now estimates regarding the number of endemic plant species for the region were not supported by any comprehensive published work for the region. The results of this study indicate that Micronesia has the world’s highest percentage of plant endemism per square kilometer out of all globally recognized insular biodiversity hotspots. A checklist of all endemic plant species for Micronesia is presented here with their corresponding geographical limits within the region. A summary of previous work and estimates is also provided noting the degree of taxonomic progress in the past several decades. A total of 364 vascular plant species are considered endemic to Micronesia, most of them being restricted to the Caroline Islands with a large percentage restricted to Palau. The checklist includes seven new combinations, one new name, and two unverified names that require additional study to verify endemic status. Overviews of each respective botanical family represented in the list are given including additional information on the Micronesian taxa. Recommendations for future work and potential projects are alluded to throughout the text highlighting major data gaps and very poorly known taxa. The following new combinations and names are made: Cyclosorus carolinensis (Hosokawa Lorence, comb. nov. , Cyclosorusgretheri (W. H. Wagner Lorence, comb. nov., Cyclosorusguamensis (Holttum Lorence, comb. nov., Cyclosorus palauensis (Hosokawa Lorence, comb. nov. , Cyclosorus rupiinsularis (Fosberg Lorence, comb. nov., Dalbergia hosokawae (Hosokawa Costion nom. nov., Syzygium trukensis (Hosokawa Costion & E. Lucas comb. nov.

  9. Orogenic plateau growth: Expansion of the Turkish-Iranian Plateau across the Zagros fold-and-thrust belt

    Science.gov (United States)

    Allen, M. B.; Saville, C.; Blanc, E. J.-P.; Talebian, M.; Nissen, E.

    2013-03-01

    This paper shows how the Turkish-Iranian Plateau grows laterally by incrementally incorporating adjacent parts of the Zagros fold-and-thrust belt. The limit of significant, seismogenic, thrusting in the Zagros (Mw > 5) occurs close to the regional 1250 m elevation contour. The seismicity cutoff is not a significant bedrock geology boundary. Elevations increase northward, toward regional plateau elevations of 2 km, implying that another process produced the extra elevation. Between the seismogenic limit of thrusting and the suture, this process is a plausibly ductile thickening of the basement, suggesting depth-dependent strain during compression. Similar depth-dependant crustal strain may explain why the Tibetan plateau has regional elevations 1500 m greater than the elevation limit of seismogenic thrusting at its margins. We estimate 68 km shortening across the Zagros Simply Folded Belt in the Fars region, and 120 km total shortening of the Arabian plate. The Dezful Embayment is a low strain zone in the western Zagros. Deformation is more intense to its northeast, in the Bakhtyari Culmination. The orogenic taper (across strike topographic gradient) across the Dezful Embayment is 0.0004, and across the Bakhtyari Culmination, 0.022. Lateral plateau growth is more pronounced farther east (Fars), where a more uniform structure has a taper of 0.010 up to elevations of 1750 m. A >100 km wide region of the Zagros further northeast has a taper of 0.002 and is effectively part of the Turkish-Iranian Plateau. Internal drainage enhances plateau development but is not a pre-requisite. Aspects of the seismicity, structure, and geomorphology of the Zagros do not support critical taper models for fold-and-thrust belts.

  10. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study

    OpenAIRE

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-ichi

    2017-01-01

    AIM To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). METHODS A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fract...

  11. Quantifying the Plutonic to Volcanic Relationship Along the Puna Plateau: Implications for Cordilleran Plateau Evolution

    Science.gov (United States)

    Ward, K. M.; Delph, J. R.; Zandt, G.; Beck, S. L.; Ducea, M. N.

    2016-12-01

    Quantifying well constrained plutonic to volcanic (P:V) ratios is inherently difficult because the tectonic processes that exhume intrusive bodies rarely preserve their extrusive equivalents. Conversely, active magmatic systems that have well-preserved volcanic deposits require sophisticated geophysical or geochemical approaches to estimate their plutonic roots and even when these sophisticated approaches are available, it is not always clear what constitutes a plutonic volume. Further complicating the enigmatic plutonic to volcanic relationship is the highly episodic nature of pluton emplacement where magmatic flare-ups produce several orders of magnitude more magmatism when compared against magmatic lulls. Despite this inherent difficulty, a growing body of independently measured P:V ratios (e.g. seismic tomography, geomorphic modeling, geological mapping/dating, and Zircon age spectra modeling) suggests the contribution of magmatic addition as an uplift mechanism in Cordilleran systems is much larger than is currently accepted. However, it remains unclear if these studies can be generalized to represent type behavior in Cordilleran systems or result from the non-uniform sampling imposed by the ability to measure large P:V ratios in only a few select and potentially anomalous regions of the American Cordillera. To better examine the role of magmatic processes in building Cordilleran high plateaus, we image the crustal seismic shear-wave velocity for an 800 km section (20.5°-28°S) of the active South American Cordillera (Puna Plateau). When placed in the context of existing geological and geophysical datasets, our seismic model reveals numerous mid-crustal low-velocity zones that we unambiguously interpret as the plutonic underpinnings associated with the voluminous silicic volcanics of the Puna Plateau. These larger P:V ratios are consistent with recent thermomechanical modeling of granitic magma intrusions that support the existence of long-lived, partially

  12. 40 CFR 81.162 - Northeast Plateau Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Northeast Plateau Intrastate Air... Air Quality Control Regions § 81.162 Northeast Plateau Intrastate Air Quality Control Region. The Northeast Plateau Intrastate Air Quality Control Region (California) consists of the territorial area...

  13. Elevational plant species richness patterns and their drivers across non-endemics, endemics and growth forms in the Eastern Himalaya.

    Science.gov (United States)

    Manish, Kumar; Pandit, Maharaj K; Telwala, Yasmeen; Nautiyal, Dinesh C; Koh, Lian Pin; Tiwari, Sudha

    2017-09-01

    Despite decades of research, ecologists continue to debate how spatial patterns of species richness arise across elevational gradients on the Earth. The equivocal results of these studies could emanate from variations in study design, sampling effort and data analysis. In this study, we demonstrate that the richness patterns of 2,781 (2,197 non-endemic and 584 endemic) angiosperm species along an elevational gradient of 300-5,300 m in the Eastern Himalaya are hump-shaped, spatial scale of extent (the proportion of elevational gradient studied) dependent and growth form specific. Endemics peaked at higher elevations than non-endemics across all growth forms (trees, shrubs, climbers, and herbs). Richness patterns were influenced by the proportional representation of the largest physiognomic group (herbs). We show that with increasing spatial scale of extent, the richness patterns change from a monotonic to a hump-shaped pattern and richness maxima shift toward higher elevations across all growth forms. Our investigations revealed that the combination of ambient energy (air temperature, solar radiation, and potential evapo-transpiration) and water availability (soil water content and precipitation) were the main drivers of elevational plant species richness patterns in the Himalaya. This study highlights the importance of factoring in endemism, growth forms, and spatial scale when investigating elevational gradients of plant species distributions and advances our understanding of how macroecological patterns arise.

  14. Threshold friction velocity of soils within the Columbia Plateau

    Science.gov (United States)

    Wind erosion only occurs when the friction velocity exceeds the threshold friction velocity (TFV) of the surface. The TFV of loessial soils commonly found across the Columbia Plateau region of the U.S. Pacific Northwest is virtually unknown even though these soils are highly erodible and a source of...

  15. Deep mantle forces and the uplift of the Colorado Plateau

    Energy Technology Data Exchange (ETDEWEB)

    Moucha, R; Forte, A M; Rowley, D B; Mitrovica, J X; Simmons, N A; Grand, S P

    2009-06-23

    Since the advent of plate tectonics, it has been speculated that the northern extension of the East Pacific Rise, specifically its mantle source, has been over-ridden by the North American Plate in the last 30 Myrs. Consequently, it has also been postulated that the opening of the Gulf of California, the extension in the Basin and Range province, and the uplift of the Colorado Plateau are the resulting continental expressions of the over-ridden mantle source of the East Pacific Rise. However, only qualitative models based solely on surface observations and heuristic, simplified conceptions of mantle convection have been used in support or against this hypothesis. We introduce a quantitative model of mantle convection that reconstructs the detailed motion of a warm mantle upwelling over the last 30 Myrs and its relative advance towards the interior of the southwestern USA. The onset and evolution of the crustal uplift in the central Basin and Range province and the Colorado Plateau is determined by tracking the topographic swell due to this mantle upwelling through time. We show that (1) the extension and magmatism in the central Basin and Range province between 25 and 10 Ma coincides with the reconstructed past position of this focused upwelling, and (2) the southwestern portion of the Colorado Plateau experienced significant uplift between 10 Ma and 5 Ma that progressed towards the northeastern portion of the plateau. These uplift estimates are consistent with a young, ca. 6 Ma, Grand Canyon model and the recent commencement of mafic magmatism.

  16. Behavior of Colorado Plateau uranium minerals during oxidation

    Science.gov (United States)

    Garrels, Robert Minard; Christ, C.L.

    1956-01-01

    Uranium occurs as U(VI) and U(IV) in minerals of the Colorado Plateau ores. The number of species containing U(VI) is large, but only two U(IV) minerals are known from the Plateau: uraninite, and oxide, and coffinite, a hydroxy-silicate. These oxidize to yield U(VI) before reacting significantly with other mineral constituents. Crystal-structure analysis has shown that U(VI) invariable occurs as uranyl ion, UO2+2. Uranyl ion may form complex carbonate or sulfate ions with resulting soluble compounds, but only in the absence of quinquevalent vanadium, arsenic, or phosphorous. In the presence of these elements in the +5 valence state, the uranyl ion is fixed in insoluble layer compounds formed by union of uranyl ion with orthovanadate, orthophosphate, or orthoarsenate. Under favorable conditions UO2+2 may react to form the relatively insoluble rutherfordine, UO2CO3, or hydrated uranyl hydroxides. These are rarely found on the Colorado Plateau as opposed to their excellent development in other uraniferous areas, a condition which is apparently related to the semiarid climate and low water table of the Plateau. Uranium may also be fixed as uranyl silicate, but little is known about minerals of this kind. In the present study emphasis has been placed on a detailing of the chemical and crystal structural changes which occur in the oxidation paragenetic sequence.

  17. Sensitivity of LUCC on the Surface Temperature of Tibetan Plateau

    Science.gov (United States)

    Qi, W.; Deng, X.; Wu, F.

    2016-12-01

    The Tibetan Plateau has an important effect on the ecological security in China, even in Asia, which makes the region become the hot spot in recently research. Under the joint influence of global change and human activities, ecosystem destabilizing and the increasing pressure on resources and environment emerge on the Tibetan Plateau, but the potential spatial sensitivity of land use and land cover changes(LUCC) on surface temperature has not been quantitatively analyzed. This study analyzed the mainly types of LUCC, urbanization, grassland degradation, deforestation on Tibetan Plateau along with Representative Concentration Pathways (RCPs) of the Intergovernmental Panel on Climate Change (IPCC). The LUCC in recent decades was first quantitatively analyzed in this study to give the basic fact with a significant increase in temperatures, reduced precipitation and increased evaporation. This study focused on the future spatio-temporal heterogeneity of the temperature and precipitation. Finally, the influencing factors with LUCC on Tibetan Plateau were simulated with the Weather Research and Forecasting (WRF) model, and the sensitivity of different land use types was spatially analyzed with Singular Value Decomposition (SVD). The results indicate that the large-area alpine grassland plays a more important role in alleviating global warming than other vegetation types do. The changes of the landscape structure resulting from the urban expansion play a significant role in intensifying regional temperature increase. In addition, the effects of LUCC on monthly average temperature change would vary from month to month with obviously spatial heterogeneity.

  18. Excessive Afforestation and Soil Drying on China's Loess Plateau

    Science.gov (United States)

    Zhang, Shuilei; Yang, Dawen; Yang, Yuting; Piao, Shilong; Yang, Hanbo; Lei, Huimin; Fu, Bojie

    2018-03-01

    Afforestation and deforestation as human disturbances to vegetation have profound impacts on ecohydrological processes influencing both water and carbon cycles and ecosystem sustainability. Since 1999, large-scale revegetation activities such as "Grain-to-Green Program" have been implemented across China's Loess Plateau. However, negative ecohydrological consequences, including streamflow decline and soil drying have emerged. Here we estimate the equilibrium vegetation cover over the Loess Plateau based on an ecohydrological model and assess the water balance under the equilibrium and actual vegetation cover over the past decade. Results show that the current vegetation cover (0.48 on average) has already exceeded the climate-defined equilibrium vegetation cover (0.43 on average) in many parts of the Loess Plateau, especially in the middle-to-east regions. This indicates a widespread overplanting, which is found to primarily responsible for soil drying in the area. Additionally, both the equilibrium vegetation cover and soil moisture tend to decrease under future (i.e., 2011-2050) climate scenarios due to declined atmospheric water supply (i.e., precipitation) and increased atmospheric water demand (i.e., potential evapotranspiration). Our findings suggest that further revegetation on the Loess Plateau should be applied with caution. To maintain a sustainable ecohydrological environment in the region, a revegetation threshold is urgently needed to guide future revegetation activities.

  19. Discovery of cryptic Armillaria solidipes genotypes within the Colorado Plateau

    Science.gov (United States)

    J. W. Hanna; N. B. Klopfenstein; M. -S. Kim; S. M. Ashiglar; A. L. Ross-Davis; G. I. McDonald

    2012-01-01

    Armillaria solidipes (= A. ostoyae) is a root-disease pathogen that causes severe losses in growth and productivity of forest trees throughout the Northern Hemisphere. This species is genetically diverse with variable disease activities across different regions of the world. In North America, A. solidipes in the Colorado Plateau exists in drier habitats and causes more...

  20. Protozoan Diversity in a productive fishpond of a tropical plateau ...

    African Journals Online (AJOL)

    A survey of the Protozoan species diversity in a productive fishpond of the Jos Plateau, Nigeria was investigated at 7 day interval over a period of 11 months. Samples were collected from water column and sediment. Protozoans were found to compose of the flagellates sarcodines and cilliates. There was a significant ...

  1. Les jeux de plateau: une géographie ludique

    Directory of Open Access Journals (Sweden)

    Frédéric BIZET

    1997-12-01

    Full Text Available Les jeux de plateau utilisent le plus souvent une carte «papier» comme support. Au-delà de l'aspect cartographique, ces jeux intègrent également des notions de territorialité et d'analyse spatiale.

  2. Geologic studies of the Columbia Plateau: a status report

    International Nuclear Information System (INIS)

    Myers, C.W.; Price, S.M.

    1979-10-01

    The results of recent geologic studies of the Columbia Plateau, with emphasis on work completed under the Basalt Waste Isolation Project, Rockwell Hanford Operations, are summarized in this report. Geologic studies were performed mostly during the period from 1977 to 1979. The major objective of these studies was to examine the feasibility of using deep underground tunnels mined into Columbia River basalt beneath the Hanford Site for final storage of nuclear waste. The results are presented in four chapters: Introduction; Regional Geology; Pasco Basin Geology; and Seismicity and Tectonics. Results from surface mapping and remote sensing studies in the Washington State portion of the Columbia Plateau are presented in the Regional Geology chapter. Results from surface mapping, borehole studies, and geophysical surveys in the Pasco Basin are presented in the Pasco Basin Geology chapter. Results that relate to the tectonic stability of the Pasco Basin and Columbia Plateau and discussion of findings from earthquake monitoring in the region for the past ten years are summarized in the Seismicity and Tectonics chapter. A volume of Appendices is included. This volume contains a description of study tasks, a description of the methodology used in geophysical surveys the geophysical survey results, a summary of earthquake records in eastern Washington, a description of tectonic provinces, and a preliminary description of the regional tectonic setting of the Columbia Plateau

  3. Plateau diffusion coefficient for arbitrary flux surface geometry

    International Nuclear Information System (INIS)

    Meier, H.K.; Hirshman, S.P.; Sigmar, D.J.; Lao, L.L.

    1981-03-01

    A relatively simple but accurate representation has been developed for magnetic flux surfaces; it is valid for finite β and it describes configurations with both ellipticity and D-shape. This representation has been applied to the computation of the diffusion coefficient in the plateau regime

  4. Rainfall Erosivity Factor for Uasin Gishu Plateau, Kenya | Kariaga ...

    African Journals Online (AJOL)

    Runoff plots were established on bare soil classified as Dystric Nitosols (Typic Rhodudults) at Moi University Main Campus, on Uasin Gishu Plateau, Kenya. The objective of the study was to determine the best erosivity factor for the area. This was found to be EI30, defined as the product of the rainstorm's kinetic energy and ...

  5. Endemic pemphigus foliaceus in Venezuela: report of two children.

    Science.gov (United States)

    González, Francisco; Sáenz, Ana Maria; Cirocco, Antonietta; Tacaronte, Inés Maria; Fajardo, Javier Enrique; Calebotta, Adriana

    2006-01-01

    Two native Yanomami children from the Venezuelan Amazonia with erythroderma were hospitalized on our service. Clinical, histologic, and immunofluorescence studies diagnosed endemic pemphigus foliaceous. Human leukocyte antigen class II showed DRB1*04 subtype *0411, which has not been previously associated with this disease. However, it shares a common epitope with all the human leukocyte antigen DRB1 alleles that have been involved in this disease among Brazilian populations. Although this condition is endemic in Brazil, our patients are the first two reported in Venezuela.

  6. Greenhouse gases emissions in rivers of the Tibetan Plateau.

    Science.gov (United States)

    Qu, Bin; Aho, Kelly Sue; Li, Chaoliu; Kang, Shichang; Sillanpää, Mika; Yan, Fangping; Raymond, Peter A

    2017-11-29

    Greenhouse gases (GHGs) emissions from streams are important to regional biogeochemical budgets. This study is one of the first to incorporate stream GHGs (CO 2 , CH 4 and N 2 O) concentrations and emissions in rivers of the Tibetan Plateau. With one-time sampling from 32 sites in rivers of the plateau, we found that most of the rivers were supersaturated with CO 2 , CH 4 and N 2 O during the study period. Medians of partial pressures of CO 2 (pCO 2 ), pCH 4 and pN 2 O were presented 864 μatm, 6.3 μatm, and 0.25 μatm respectively. Based on a scaling model of the flux of gas, the calculated fluxes of CO 2 , CH 4 and N 2 O (3,452 mg-C m 2 d -1 , 26.7 mg-C m 2 d -1 and 0.18 mg-N m 2 d -1 , respectively) in rivers of the Tibetan Plateau were found comparable with most other rivers in the world; and it was revealed that the evasion rates of CO 2 and CH 4 in tributaries of the rivers of the plateau were higher than those in the mainstream despite its high altitude. Furthermore, concentrations of GHGs in the studied rivers were related to dissolved carbon and nitrogen, indicating that riverine dissolved components could be used to scale GHGs envision in rivers of the Tibetan Plateau.

  7. Integrated geophysical study of the northeastern margin of Tibetan Plateau

    Science.gov (United States)

    Shi, L.; Meng, X.; Guo, L.

    2011-12-01

    Tibetan Plateau, the so-called "Roof of the World", is a direct consequence of collision of the Indian plate with the Eurasian plate starting in the early Cenozoic time. The continent-continent collision is still going on. The northeastern margin of Tibetan Plateau is the front part of the Tibetan Plateau extends to mainland and favorable area for studying uplift and deformation of the Tibetan Plateau. In the past decades, a variety of geophysical methods were conducted to study geodynamics and geological tectonics of this region. We assembled satellite-derived free-air gravity anomalies with a resolution of one arc-minute from the Scripps Institution of Oceanography, and reduced them to obtain Complete Bouguer Gravity Anomalies. Then we gridded Complete Bouguer Gravity Anomalies on a regular grid, and subsequently processed them with the preferential continuation method to attenuate high-frequency noise and analyzed regional and residual anomalies. We also calculated tilt-angle derivative of Complete Bouguer Gravity Anomalies to derive clearer geological structures with more details. Then we calculated the depth distribution of the Moho discontinuity surface in this area by 3D density interface inversion. From the results of preliminary processing, we analyzed the main deep faults and geological tectonics in this region. We extracted seven important profiles' data of Complete Bouguer Gravity Anomalies in this area, and then did forward modeling and inversion on each profile with constraints of geological information and other geophysical data. In the future, we will perform 3D constrained inversion of Complete Bouguer Gravity Anomalies in this region for better understanding deep structure and tectonics of the northeastern margin of Tibetan Plateau. Acknowledgment: We acknowledge the financial support of the SinoProbe project (201011039), the Fundamental Research Funds for the Central Universities (2010ZY26 2011PY0184), and the National Natural Science Foundation

  8. Intracontinental Deformation in the NW Iranian Plateau and Comparisons with the Northern Margin of the Tibetan Plateau

    Science.gov (United States)

    Chen, L.; Jiang, M.; Talebian, M.; Wan, B.; Ai, Y.; Ghods, A.; Sobouti, F.; Xiao, W.; Zhu, R.

    2017-12-01

    This study investigates the intracontinental deformation and its relationship with the structure of the crust and uppermost mantle in the NW Iranian plateau by combining new seismic and geological observations, to understand how this part of the plateau deformed to accommodate the Arabia-Eurasia plate collision and how the property of the lithosphere controls the deformation pattern. In contrast to the adjacent Anatolian block that exhibits westward large-scale extrusion, the northwesternmost part of the Iranian plateau shows dispersed intracontinental deformations with the development of numerous small-scale and discontinuous right-lateral strike-slip faults. The dispersed surface structures and deformation pattern correspond well to the active volcanism and seismically slow crust and uppermost mantle, and hence a weak lithosphere of the area. Further to the southeast are the western part of the Alborz Mountains and the southern Caspian Sea, both of which are characterized by stronger and more rigid lithosphere with relatively fast crust and uppermost mantle and absence of Quaternary volcanoes. A sharp Moho offset of 18 km has been imaged at the border of the Alborz and southern Caspian Sea using teleseismic receiver function data from a dense seismic array deployed under a collaborative project named "China-Iran Geological and Geophysical Survey in the Iranian Plateau (CIGSIP)". The sharp Moho offset and the minor undulations of the Moho on both sides indicate insignificant intracrustal deformation but mainly relative crustal movements between the Alborz Mountains and southern Caspian Sea, a behavior consistent with the relatively rigid nature of the lithosphere. Similar Moho offsets and lithospheric structures have been reported at the borders between the Kunlun Mountains and Qaidam or Tarim Basins in the northern margin of the Tibetan plateau, suggesting the occurrence of relative crustal movements with the effects of rigid continental lithosphere in the region

  9. Strong evidence for changing fish reproductive phenology under climate warming on the Tibetan Plateau.

    Science.gov (United States)

    Tao, Juan; He, Dekui; Kennard, Mark J; Ding, Chengzhi; Bunn, Stuart E; Liu, Chunlong; Jia, Yintao; Che, Rongxiao; Chen, Yifeng

    2018-05-01

    Phenological responses to climate change have been widely observed and have profound and lasting effects on ecosystems and biodiversity. However, compared to terrestrial ecosystems, the long-term effects of climate change on species' phenology are poorly understood in aquatic ecosystems. Understanding the long-term changes in fish reproductive phenology is essential for predicting population dynamics and for informing management strategies, but is currently hampered by the requirement for intensive field observations and larval identification. In this study, a very low-frequency sampling of juveniles and adults combined with otolith measurements (long axis length of the first annulus; LAFA) of an endemic Tibetan Plateau fish (Gymnocypris selincuoensis) was used to examine changes in reproductive phenology associated with climate changes from the 1970s to 2000s. Assigning individual fish to their appropriate calendar year class was assisted by dendrochronological methods (crossdating). The results demonstrated that LAFA was significantly and positively associated with temperature and growing season length. To separate the effects of temperature and the growing season length on LAFA growth, measurements of larval otoliths from different sites were conducted and revealed that daily increment additions were the main contributor (46.3%), while temperature contributed less (12.0%). Using constructed water-air temperature relationships and historical air temperature records, we found that the reproductive phenology of G. selincuoensis was strongly advanced in the spring during the 1970s and 1990s, while the increased growing season length in the 2000s was mainly due to a delayed onset of winter. The reproductive phenology of G. selincuoensis advanced 2.9 days per decade on average from the 1970s to 2000s, and may have effects on recruitment success and population dynamics of this species and other biota in the ecosystem via the food web. The methods used in this study

  10. A treasure of endemic fauna of Mauritius and Rodrigues

    NARCIS (Netherlands)

    Winters, Ria

    2011-01-01

    This publication deals with the endemic species of the Indian ocean islands of Mauritius and Rodrigues. The author describes the extinct and extant birds and animals in word and art. The book is illustrated with the authors drawings and paintings. Full colour.

  11. Trichomonad infection in endemic and introduced columbids in the Seychelles.

    Science.gov (United States)

    Bunbury, N

    2011-07-01

    Island endemic avifaunas face many threats, including the now well-documented impacts of pathogens. The impacts of pathogens on the endemic Seychelles avifauna, however, have been little studied. The protozoan parasite Trichomonas gallinae has been shown to reduce survival and reproductive success of the endemic Pink Pigeon Columba mayeri on the nearby island of Mauritius. I investigated trichomonad infection prevalence and pathogenicity in endemic Seychelles Blue Pigeons, Alectroenas pulcherrima, and two introduced species of columbid, the Madagascar Turtle-dove, Streptopelia picturata, and the Barred Ground Dove, Geopelia striata, on the Seychelles island of Mahé during September-October 2007. I asked whether: 1) trichomonad infections occur in these species; 2) prevalence varies among species; and 3) birds show any signs of pathogenicity consistent with tricho-monosis. I use the results to assess the potential threat of this pathogen to A. pulcherrima. All three species were infected with trichomonads, and the overall prevalence was 27.5%. Alectroenas pulcherrima had higher prevalence (47.1%) than the two introduced species combined (24.3%). No infected individuals showed any signs of disease. These findings suggest that trichomonad parasites should be considered as a potential disease threat to the A. pulcherrima population.

  12. Distribution and protection of endemic or threatened rodents ...

    African Journals Online (AJOL)

    highest in the south-western parts of the country, and hotspots of endemism cOincide with those of species rich- ness. However, Red ... species richness hotspot in the Succulent Karoo contains no existing reserves, whereas all Red Data Book spe- ... conserve all aspects of biodiversity, but of historical ad hoc decisions ...

  13. Small mammals distribution and diversity in a plague endemic area ...

    African Journals Online (AJOL)

    Small mammals play a role in plague transmission as hosts in all plague endemic areas. Information on distribution and diversity of small mammals is therefore important for plague surveillance and control in such areas. The objective of this study was to investigate small mammals' diversity and their distribution in plague ...

  14. Patterns of distribution and protection status of the endemic ...

    African Journals Online (AJOL)

    The majority of these endemics are small mammals and many are listed in the Red Data Book, especially those restricted to the Nama-and Succulent Karoo. This is of concern, as both areas are inadequately protected by the existing protected areas. The coastal forests also contain many Red Data Book species, particularly ...

  15. Biological Invasion and Loss of Endemic Biodiversity in the Thar ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 3. Nature Watch - Biological Invasion and Loss of Endemic Biodiversity in the Thar Desert. Ishwar Prakash. Feature Article Volume 6 Issue 3 March 2001 pp 76-85. Fulltext. Click here to view fulltext PDF. Permanent link:

  16. Allozyme diversity in Macbridea alba (Lamiaceae), an endemic Florida mint

    Science.gov (United States)

    M.J.W. Godt; Joan L. Walker; J.L. Hamrick

    2004-01-01

    Macbridea alba is a herbaceous perennial mint endemic to the panhandle region of Florida. We used starch gel electrophoresis to describe allozyme diversity and genetic structure in this federally threatened plant. Ten populations were analyzed, with an average sample size of 47 plants (range 41-48 plants) per population. Of the 22 loci analyzed, 11 (...

  17. Patterns of endemicity and range restriction among southern African ...

    African Journals Online (AJOL)

    Patterns of endemicity and range restriction among southern African coastal marine invertebrates. RJ Scott, CL Griffiths, TB Robinson. Abstract. Southern Africa supports a rich marine biota of 12 734 currently described marine species. Although the distribution and overall species-richness patterns of several component ...

  18. Evolution of endemism on a young tropical mountain

    NARCIS (Netherlands)

    Merckx, V.; Hendriks, K.; Beentjes, K.; Mennes, C.B.; Becking, L.E.; Geurts, R.

    2015-01-01

    Tropical mountains are hot spots of biodiversity and endemism1–3, but the evolutionary origins of their unique biotas are poorly understood4. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these

  19. The endemicity of dracunculiasis, transmission pattern and ecology ...

    African Journals Online (AJOL)

    Studies on the endemicity of dracunculiasis, it's transmission pattern and ecology of cyclopoid copepods in Ezza North Local Government Area of Ebonyi State Nigeria were carried out between January and December 2001. Of the 2226 persons examined in eight communities, 426 (19.1%) were infected. This included 24 ...

  20. Evolution of endemism on a young tropical mountain

    NARCIS (Netherlands)

    Merckx, Vincent S F T; Hendriks, Kasper P; Beentjes, Kevin K; Mennes, Constantijn B; Becking, Leontine E; Peijnenburg, Katja T C A; Afendy, Aqilah; Arumugam, Nivaarani; de Boer, Hugo; Biun, Alim; Buang, Matsain M; Chen, Ping-Ping; Chung, Arthur Y C; Dow, Rory; Feijen, Frida A A; Feijen, Hans; Feijen-van Soest, Cobi; Geml, József; Geurts, René; Gravendeel, Barbara; Hovenkamp, Peter; Imbun, Paul; Ipor, Isa; Janssens, Steven B; Jocqué, Merlijn; Kappes, Heike; Khoo, Eyen; Koomen, Peter; Lens, Frederic; Majapun, Richard J; Morgado, Luis N; Neupane, Suman; Nieser, Nico; Pereira, Joan T; Rahman, Homathevi; Sabran, Suzana; Sawang, Anati; Schwallier, Rachel M; Shim, Phyau-Soon; Smit, Harry; Sol, Nicolien; Spait, Maipul; Stech, Michael; Stokvis, Frank; Sugau, John B; Suleiman, Monica; Sumail, Sukaibin; Thomas, Daniel C; van Tol, Jan; Tuh, Fred Y Y; Yahya, Bakhtiar E; Nais, Jamili; Repin, Rimi; Lakim, Maklarin; Schilthuizen, Menno

    2015-01-01

    Tropical mountains are hot spots of biodiversity and endemism, but the evolutionary origins of their unique biotas are poorly understood. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these

  1. Evolution of endemism on a young tropical mountain

    NARCIS (Netherlands)

    Merckx, V.S.F.T.; Hendriks, K.P.; Beentjes, K.K.; Mennes, C.B.; Becking, L.E.; Peijnenburg, K.T.C.A.; Afendy, A.; Arumugam, N.; de Boer, H.; Biun, A.; Buang, M.M.; Chen, P.P.; Chung, A.Y.C.; Dow, R..; Feijen, F.A.A.; Feijen, H.; Feijen-van Soest, C.; Geml, J.; Geurts, R.; Gravendeel, B.; Hovenkamp, P.; Imbun, P.; Ipor, I.; Janssens, S.B.; Jocqué, M.; Kappes, H.; Khoo, E.; Koomen, P.; Lens, F.; Majapun, R.J.; Morgado, L.N.; Neupane, S.; Nieser, N.; Pereira, J.T.; Rahman, H.; Sabran, S.; Sawang, A.; Schwallier, R.M.; Shim, P.S.; Smit, H.; Sol, N.; Spait, M.; Stech, M.; Stokvis, F.; Sugau, J.B.; Suleiman, M.; Sumail, S.; Thomas, D.C.; van Tol, J.; Tuh, F.Y.Y.; Yahya, B.E.; Nais, J.; Repin, R.; Lakim, M.; Schilthuizen, M.

    2015-01-01

    Tropical mountains are hot spots of biodiversity and endemism1, 2, 3, but the evolutionary origins of their unique biotas are poorly understood4. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of

  2. Genetic variability in the population of the endemic bee Anthophora ...

    African Journals Online (AJOL)

    The genetic diversity and spatial genetic population structure of the solitary bee Anthophora pauperata Walker 1871, a species endemic to St Katherine Protectorate, were studied by RAPD markers in seven wadis in the St Katherine Protectorate, South Sinai, Egypt. High levels of genetic diversity were found, mostly within ...

  3. Factors Affecting Agroforestry Sustainability in Bee Endemic Parts of ...

    African Journals Online (AJOL)

    This paper attempts, in an exploratory manner, to identify the various ways in which bad beekeeping and honey hunting practices result in the loss of important multi-purpose agro-forestry tree species in bee endemic parts of South Eastern Nigeria. Both qualitative and quantitative approaches (Participatory Rural Appraisal ...

  4. Distribution and protection of endemic or threatened rodents ...

    African Journals Online (AJOL)

    Species richness of the target species is highest in the south-western parts of the country, and hotspots of endemism coincide with those of species richness. However, Red Data Book species hotspots are confined to the north-eastern parts of the country. One species richness hotspol in the Succulent Karoo contains no ...

  5. Evaluation of hospital disinfection as a means of controlling endemic ...

    African Journals Online (AJOL)

    Evaluation of hospital environment disinfection as a means of controlling endemic nosocomial pathogens in a University Teaching Hospital in Nigeria was evaluated. Disinfectant used in the Hospital was collected from the Infection Control unit and prepared in different concentrations. The isolated bacterial species from the ...

  6. Historic forests and endemic mountain pine beetle and dwarf mistletoe

    Science.gov (United States)

    Jose Negron

    2012-01-01

    Mountain pine beetle has always been a significant disturbance agent in ponderosa and lodgepole pine forests in Colorado. Most studies have examined the impacts to forest structure associated with epidemic populations of a single disturbance agent. In this paper we address the role of endemic populations of mountain pine and their interactions with dwarf mistletoe...

  7. Cotrimoxazole for childhood febrile illness in Malaria-endemic regions

    African Journals Online (AJOL)

    ren younger than 5 years of age was evaluated in. Malawi. ... limitations in diagnostic technology and personnel, disease-specific clinical ... In practice, the World. Health Organisation (WHO) recommends that in highly endemic areas all young children with fever should be treated for malaria, because of the likeli- hood of ...

  8. Investigating The Travelling Wave Solution For an SIR Endemic ...

    African Journals Online (AJOL)

    This paper presents the travelling wave solution for an SIR endemic disease model with no disease related death when the spatial spread of the susceptible is not negligible. In this case the disease is driven by both the susceptible and the infective classes. The population is open since the disease is habitually prevalent in ...

  9. An Investigation on the antimicrobial activity of some endemic plant ...

    African Journals Online (AJOL)

    In this study performed on six endemic plant species, antimicrobial activity was observed in Campanula lyrata subsp.lyrata and Abies nordmanniana subsp. bornmuelleriana plants. The minimum inhibitory concentration of C. lyrata subsp. lyrata (leaf and flower) extract was found to be 29 mg/ml for Baccillus subtilis and 14.5 ...

  10. Rediscovery of Curcuma sumatrana (Zingiberaceae) endemic to West Sumatra

    NARCIS (Netherlands)

    Ardiyani, M.; Anggara, A.; Leong-Škorničková, J.

    2011-01-01

    A recent exploration of Sumatra resulted in the re-collection of Curcuma sumatrana, an endemic Zingiberaceae species of unclear identity that was first described by Miquel nearly 150 years ago. The history of this species is discussed, a detailed description with a colour plate is provided and a

  11. Clostridium difficile infection in an endemic setting in the Netherlands

    NARCIS (Netherlands)

    Hensgens, M. P. M.; Goorhuis, A.; van Kinschot, C. M. J.; Crobach, M. J. T.; Harmanus, C.; Kuijper, E. J.

    2011-01-01

    The purpose of this investigation was to study risk factors for Clostridium difficile infection (CDI) in an endemic setting. In a 34-month prospective case-control study, we compared the risk factors and clinical characteristics of all consecutively diagnosed hospitalised CDI patients (n = 93) with

  12. Conservation assessment of the endemic plants from Kosovo

    Directory of Open Access Journals (Sweden)

    Millaku Fadil

    2017-06-01

    Full Text Available Sixteen endemic plant taxa were selected from Kosovo, according to the IUCN standards and for each taxon the risk assessment and threat category has been assigned. The taxa were compared with their previous status from fifteen years ago. From sixteen plant taxa, which were included in this work, four are Balkan endemics, whereas, eight of them are local endemics and four of the taxa are stenoendemics. Six of the taxa are grown exclusively on serpentine soils, five of them on limestone substrate, four of them in carbonate substrate, yet only one in silicate substrate. The work has been done based on the standard working methodologies of the IUCN (Guidelines for Using the IUCN Red List Categories and Criteria – Version 8.1. The most threatened plant taxa is Solenanthus krasniqii – which after its observance has only 20 mature individuals. As a result of the wild collection of the medicinal and aromatic plants, from the local population, Sideritis scardica is about to be completely go extinct. The aim of this study was to assess the state of endemics in the threats possessed to them during the previous times, present and predicting the trends for the upcoming years.

  13. Grass survey of the Itremo Massif records endemic central highland ...

    African Journals Online (AJOL)

    Twenty species are endemic to the central highlands, and a further 1 4 species are restricted to Madagascar. Five ecological groups of grasses were identified in the Itremo Massif: shade species in gallery forests, open wet area species, fire grasses, anthropogenic disturbance associated grasses and rock-dwelling grasses.

  14. Faeco-histological Method of Studying Worm Endemicity with the ...

    African Journals Online (AJOL)

    Worms are endemic in various parts of the world, the patterns varying from community to community, even in the same country. A rough index of those common among Nigerians of the Igbo ethnic group has been obtained using a histological study of the ova present in the luminal faeces of the vermiform appendix in 559 ...

  15. Functional species traits of carabid beetles living in two riparian alder forests of the Sila plateau subject to different disturbance factors (Coleoptera: Carabidae

    Directory of Open Access Journals (Sweden)

    Antonio Mazzei

    2015-06-01

    Full Text Available We studied carabid beetle assemblages found in riparian black alder forests in the Sila plateau (Southern Apennines. These carabid assemblages are characterized by a high incidence of endemic small-sized, low dispersal, highly stenotopic (hygrophilic, and trophycally specialized species. To evaluate the influence of anthropogenic disturbance on these insects, we compared carabid assemblage of an old undisturbed forest (65-170y, wilderness landscape with that of a younger, partly grazed stand (40-60y, cropland landscape. The carabid assemblage of the disturbed stand was characterized by a higher number of species, but showed a lower incidence of zoophagous specialists and brachypterous beetles, with many species probably coming from an adjacent cropland. However, the disturbed stand maintains almost 80% of the core species found in the older forest, which suggests that these insects are not particularly sensitive to disturbance factors represented by periodic wood harvesting and extensive cattle grazing.

  16. [The pathogenic ecology research on plague in Qinghai plateau].

    Science.gov (United States)

    Dai, Rui-xia; Wei, Bai-qing; Li, Cun-xiang; Xiong, Hao-ming; Yang, Xiao-yan; Fan, Wei; Qi, Mei-ying; Jin, Juan; Wei, Rong-jie; Feng, Jian-ping; Jin, Xing; Wang, Zu-yun

    2013-12-01

    To study the pathogenic ecology characteristics of plague in Qinghai plateau. Applied molecular biology techniques, conventional technologies and geographic information system (GIS) to study phenotypic traits, plasmid spectrum, genotype, infected host and media spectrum etc.of 952 Yersinia pestis strains in Qinghai plateau plague foci, which were separated from different host and media in different regions during 1954 to 2012. The ecotypes of these strains were Qingzang plateau (91.49%, 871/952),Qilian mountain (6.41%, 61/952) and Microtus fuscus (1.26%, 12/952).83.6% (796/952) of these strains contained all the 4 virulence factors (Fr1, Pesticin1,Virulence antigen, and Pigmentation), 93.26% (367/392) were velogenic strains confirmed by virulence test.725 Yersinia pestis strains were separated from Qinghai plateau plague foci carried 9 kinds of plasmid, among which 713 strains from Marmot himalayan plague foci carried 9 kinds of plasmid, the Mr were 6×10(6), 7×10(6), 23×10(6), 27×10(6), 30×10(6), 45×10(6), 52×10(6), 65×10(6) and 92×10(6) respectively. 12 Yersinia pestis strains were separated from Microtus fuscus plague foci carried only 3 kinds of plasmid, the Mr were 6×10(6), 45×10(6), 65×10(6). Meanwhile, the strains carrying large plasmid (52×10(6), 65×10(6) and 92×10(6)) were only distributed in particular geographical location, which had the category property. The research also confirmed that 841 Yersinia pestis strains from two kinds of plague foci in Qinghai plateau had 11 genomovars. The strains of Marmot himalayan plague foci were given priority to genomovar 5 and 8, amounted to 611 strains, genomovar 8 accounted for 56.00% (471/841), genomovar 5 accounted for 23.07% (194/841). Besides, 3 new genomovars, including new 1(62 strains), new 2(52 strains), new 3(48 strains) were newly founded, and 12 strains of Microtus fuscus plague foci were genomovar 14. The main host and media of Qinghai plateau plague foci directly affected the spatial

  17. Exploring the undulating plateau: the future of global oil supply.

    Science.gov (United States)

    Jackson, Peter M; Smith, Leta K

    2014-01-13

    In this paper, we analyse the factors that will influence long-term oil supply and describe the future form of the global oil supply profile as an 'undulating plateau' rather than an irreversible, short-term peak or an ever upward trend of increasing production. The ultimate transition from a world of relatively plentiful and cheap oil to one of tight supply and high cost will be slow and challenging. An understanding of the signposts for the future path of supply and the drivers of that profile will be critical to managing the transition. The ultimate form of the global supply curve may well be dictated by demand evolution rather than a limited resource endowment in the longer term. Several factors will probably control future global oil supply. We believe that the scale of global oil resource will not constitute a physical supply limit for at least the next two or three decades. However, all categories of oil resources are already more expensive to develop than in the past, requiring high oil prices to stimulate supply growth. Lower rates of oil demand growth relative to economic growth, combined with more challenging supply growth, will probably lead to an undulating plateau sometime after 2040, with demand from non-Organization for Economic Cooperation and Development states continuing to dominate. Upstream investment requirements and oil price volatility will increase towards and beyond the undulating production plateau. In this new world, high oil prices will induce demand destruction, fuel substitution and ever increasing energy efficiency. As we discuss below, the fundamental differences between the IHS Cambridge Energy Research Associates' (IHS CERA) view of the future of oil supply and many peak oil supply models are the timing of the onset of a dramatic slowdown in the rate of growth of supply and the existence or otherwise of a production plateau. We do not dispute that supply will plateau and eventually fall; the question is when, how and at what price

  18. Late Quaternary Soil Development Enhances Aeolian Landform Stability, Moenkopi Plateau, Southern Colorado Plateau, USA

    Directory of Open Access Journals (Sweden)

    Amy L. Ellwein

    2018-04-01

    Full Text Available The Moenkopi dune field in northeastern Arizona covers roughly 1250 km2, but most of the field is inactive. Dune deposits on the Moenkopi Plateau (MP have remained inactive throughout the Holocene despite periods of elevated aridity or historical reductions of vegetation cover by livestock grazing. We argue that this inactivity is not because of any diminishment of driving forces in the aeolian system (e.g., insufficient winds, but rather because of increased cohesion due to soil development that enhances resistance to wind erosion. Abundant aeolian sediments were supplied to the Black Mesa region by the Little Colorado River and its tributaries during the late Pleistocene (MIS 2 and 3, which enabled the development of climbing dunes and transport of sand over the Adeii Eechii Cliffs and onto the MP. These deposits (Qe1 stabilized during the Pleistocene/Holocene climatic transition (~12–7.5 ka because of reduced sediment supply and high dust flux which resulted in rapid soil formation. Erosion of climbing dunes/sand ramps from the Adeii Eechii Cliffs eliminated delivery of large quantities of new sand to the MP during the mid to late Holocene. Soil development within the Qe1 mantle increased sediment cohesion and prevented widespread aeolian reactivation during the Holocene, despite the occurrence of conditions (wind speed, climate, etc. under which dune reactivation would be expected. Drylands comprise roughly 40% of the land cover of earth and climate models predict their expansion. Pedogenic stability is not commonly considered in climate-based models used to predict aeolian activity. To improve predictions of future dune activity in drylands, the degree of soil development in aeolian deposits should be considered when evaluating sediment availability in aeolian systems.

  19. Future of endemic flora of biodiversity hotspots in India.

    Directory of Open Access Journals (Sweden)

    Vishwas Sudhir Chitale

    Full Text Available India is one of the 12 mega biodiversity countries of the world, which represents 11% of world's flora in about 2.4% of global land mass. Approximately 28% of the total Indian flora and 33% of angiosperms occurring in India are endemic. Higher human population density in biodiversity hotspots in India puts undue pressure on these sensitive eco-regions. In the present study, we predict the future distribution of 637 endemic plant species from three biodiversity hotspots in India; Himalaya, Western Ghats, Indo-Burma, based on A1B scenario for year 2050 and 2080. We develop individual variable based models as well as mixed models in MaxEnt by combining ten least co-related bioclimatic variables, two disturbance variables and one physiography variable as predictor variables. The projected changes suggest that the endemic flora will be adversely impacted, even under such a moderate climate scenario. The future distribution is predicted to shift in northern and north-eastern direction in Himalaya and Indo-Burma, while in southern and south-western direction in Western Ghats, due to cooler climatic conditions in these regions. In the future distribution of endemic plants, we observe a significant shift and reduction in the distribution range compared to the present distribution. The model predicts a 23.99% range reduction and a 7.70% range expansion in future distribution by 2050, while a 41.34% range reduction and a 24.10% range expansion by 2080. Integration of disturbance and physiography variables along with bioclimatic variables in the models improved the prediction accuracy. Mixed models provide most accurate results for most of the combinations of climatic and non-climatic variables as compared to individual variable based models. We conclude that a regions with cooler climates and higher moisture availability could serve as refugia for endemic plants in future climatic conditions; b mixed models provide more accurate results, compared to single

  20. Future of endemic flora of biodiversity hotspots in India.

    Science.gov (United States)

    Chitale, Vishwas Sudhir; Behera, Mukund Dev; Roy, Partha Sarthi

    2014-01-01

    India is one of the 12 mega biodiversity countries of the world, which represents 11% of world's flora in about 2.4% of global land mass. Approximately 28% of the total Indian flora and 33% of angiosperms occurring in India are endemic. Higher human population density in biodiversity hotspots in India puts undue pressure on these sensitive eco-regions. In the present study, we predict the future distribution of 637 endemic plant species from three biodiversity hotspots in India; Himalaya, Western Ghats, Indo-Burma, based on A1B scenario for year 2050 and 2080. We develop individual variable based models as well as mixed models in MaxEnt by combining ten least co-related bioclimatic variables, two disturbance variables and one physiography variable as predictor variables. The projected changes suggest that the endemic flora will be adversely impacted, even under such a moderate climate scenario. The future distribution is predicted to shift in northern and north-eastern direction in Himalaya and Indo-Burma, while in southern and south-western direction in Western Ghats, due to cooler climatic conditions in these regions. In the future distribution of endemic plants, we observe a significant shift and reduction in the distribution range compared to the present distribution. The model predicts a 23.99% range reduction and a 7.70% range expansion in future distribution by 2050, while a 41.34% range reduction and a 24.10% range expansion by 2080. Integration of disturbance and physiography variables along with bioclimatic variables in the models improved the prediction accuracy. Mixed models provide most accurate results for most of the combinations of climatic and non-climatic variables as compared to individual variable based models. We conclude that a) regions with cooler climates and higher moisture availability could serve as refugia for endemic plants in future climatic conditions; b) mixed models provide more accurate results, compared to single variable based

  1. Moderate and high endemicity of schistosomiasis is a predictor of the endemicity of soil-transmitted helminthiasis - Systematic review

    Science.gov (United States)

    Yajima, A.; Gabrielli, A. F.; Montresor, A.; Engels, D.

    2017-01-01

    The authors conducted a systematic literature review with the following aims: (i) to investigate how frequently soil-transmitted helminthiasis (STH) infections are endemic where schistosomiasis is present; and (ii) to assess the correlation between the risk level of schistosomiasis and that of STH. Among 155 sites on which data were collected and analyzed, schistosomiasis was present in 130 sites, all of which were also co-endemic for STH, whereas 25 sites were endemic only for STH. Out of 83 sites where at least one biannual round of preventive chemotherapy (PC) for schistosomiasis is recommended, 94% were also eligible for at least a yearly round of PC against STH. And among 21 sites where PC for schistosomiasis is recommended once a year, 81% were also eligible for at least a yearly round of PC for STH. This fact provides managers of control programmes with the operationally important indication that use of available information on endemicity of schistosomiasis is a valid tool to predict the presence of STH in the same geographical area as well as to estimate the need of PC for STH. The implementation of this tool is expected to save financial and human resources and help accelerate the scale-up of PC throughout the world. PMID:21215979

  2. Moderate and high endemicity of schistosomiasis is a predictor of the endemicity of soil-transmitted helminthiasis: a systematic review.

    Science.gov (United States)

    Yajima, A; Gabrielli, A F; Montresor, A; Engels, D

    2011-02-01

    The authors conducted a systematic literature review with the following aims: to investigate how frequently soil-transmitted helminthiasis (STH) infections are endemic where schistosomiasis is present; and to assess the correlation between the risk level of schistosomiasis and that of STH. Among 155 sites on which data were collected and analyzed, schistosomiasis was present in 130, all of which were also co-endemic for STH, whereas 25 sites were endemic only for STH. Ninety percent (117 out of 130) of the areas eligible for preventive chemotherapy (PC) against schistosomiasis are also eligible for PC against STH. This fact provides managers of control programmes with the operationally important indication that use of available information on endemicity of schistosomiasis is a valid tool to predict the presence of STH in the same geographical area and to estimate the need of PC for STH. The implementation of this tool is expected to save financial and human resources and help accelerate the scale-up of PC throughout the world. Copyright © 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  3. Neglected, semimembranosus osteochondral avulsion fracture of the posteromedial tibial plateau

    Directory of Open Access Journals (Sweden)

    Rakesh John

    2018-06-01

    Full Text Available Semimembranosus avulsion fracture is infrequently reported and is easy to miss on plain radiographs; the mechanism of injury is highly controversial. Initial reports linked it to anterior cruciate ligament and medial meniscal tears. We report an osteochondral semimembranosus avulsion fracture of the posteromedial tibial plateau with associated posterior cruciate ligament rupture. Also described is a novel surgical fixation technique for such osteochondral fractures where the surgical exposure is limited due to the obliquity of the fracture line resulting in a greater involvement of the articular cartilage than the small bony component. The fixation technique described may be used for osteochondral fractures where the application of a conventional compression screw may not be feasible. Keywords: Osteochondral fracture, Semimembranosus avulsion fracture, Posteromedial tibial plateau, Neglected, Nonunion

  4. Neoclassical kinetic theory near an X point: Plateau regime

    International Nuclear Information System (INIS)

    Solano, E.R.; Hazeltine, R.D.

    1994-01-01

    Traditionally, neoclassical transport calculations ignore poloidal variation of the poloidal magnetic field. Near an X point of the confining field of a diverted plasma, the poloidal field is small, causing guiding centers to linger at that poloidal position. A study of how neoclassical transport is affected by this differential shaping is presented. The problem is solved in general in the plateau regime, and a model poloidal flux function with an X point is utilized as an analytic example to show that the plateau diffusion coefficient can change considerably (factor of 2 reduction). Ion poloidal rotation is proportional to the local value of B pol but otherwise it is not strongly affected by shaping. The usual favorable scaling of neoclassical confinement time with plasma current is unaffected by the X point

  5. Minimal surfaces, stratified multivarifolds, and the plateau problem

    CERN Document Server

    Thi, Dao Trong; Primrose, E J F; Silver, Ben

    1991-01-01

    Plateau's problem is a scientific trend in modern mathematics that unites several different problems connected with the study of minimal surfaces. In its simplest version, Plateau's problem is concerned with finding a surface of least area that spans a given fixed one-dimensional contour in three-dimensional space--perhaps the best-known example of such surfaces is provided by soap films. From the mathematical point of view, such films are described as solutions of a second-order partial differential equation, so their behavior is quite complicated and has still not been thoroughly studied. Soap films, or, more generally, interfaces between physical media in equilibrium, arise in many applied problems in chemistry, physics, and also in nature. In applications, one finds not only two-dimensional but also multidimensional minimal surfaces that span fixed closed "contours" in some multidimensional Riemannian space. An exact mathematical statement of the problem of finding a surface of least area or volume requir...

  6. [Dynamic changes of Ruoergai Plateau wetland ecosystem service value].

    Science.gov (United States)

    Zhang, Xiao-Yun; Lü, Xian-Guo; Shen, Song-Ping

    2009-05-01

    Based on the satellite remote sensing data acquired in 1975 and 2006, and by using the assessment method of ecosystem service value, the dynamic changes of physical production value, gas regulation value, and water storage value of Ruoergai Plateau wetland ecosystem in 1975-2006 were studied. During study period, the total value of the three services decreased from 19.59 billion RMB Yuan to 12.38 billion Yuan RMB, among which, physical production value increased by 0.302 billion RMB Yuan, while the gas regulation and water storage value decreased by 7.507 billion RMB Yuan. The benefit from the increase of physical production was much less than the loss of ecosystem degradation. Overgrazing induced the biomass reduction and soil deterioration, resulting in the decline of Ruoergai Plateau wetland ecosystem service value and service capacity.

  7. Genetic connectivity and self-replenishment of inshore and offshore populations of the endemic anemonefish, Amphiprion latezonatus

    KAUST Repository

    Steinberg, Rosemary; van der Meer, Martin; Walker, Emily; Berumen, Michael L.; Hobbs, Jean-Paul A.; van Herwerden, Lynne

    2016-01-01

    and small distribution ranges (endemics). Marine endemics often exist as meta-populations distributed among few isolated locations. Determining genetic connectivity among these locations is essential to understanding the recovery potential of endemics after

  8. Interactions between ecosystems and hydrology in the Loess Plateau

    Science.gov (United States)

    Fu, B.; Wang, S.

    2017-12-01

    The Loess Plateau is located in the arid and semi-arid temperate continental monsoon climatic zone. Large-scale "Grain-for-Green" project has been implemented in the since 1999, which has made remarkable contribution to the soil and water control, but also has led to some negative ecological effects. Understanding the interactions between ecosystems and hydrology is significant for the vegetation carrying capacity assessment and guiding the vegetation restoration. We observed the soil moisture at multiple scales including slope, catchment and transect across Loess Plateau to analyze the effects of land use change and its trend along the precipitation gradient. Remote sensing data also used to capture the spatiotemporal variance of soil moisture in the Loess Plateau, as well as the in-situ measured soil moisture decrease following the massive re-vegetation. We found soil moisture decrease in response to the massive re-vegetation occurred in a transition zone of grass-forest ecosystems with annual precipitation between 450-550 mm. The average runoff in the Loess Plateau also decreased continuously during the period 1961-2009 (average rate of -0.9 mm yr-1, P < 0.001). Human intervention played a dominant role in creating the transition points, Water yield (i.e., the ratio of runoff to precipitation) decreased following each anthropogenic transition, causing a 56% reduction in available freshwater resources during the period 1961-2009. From currently revegetated areas and human water demand, we estimate a threshold of NPP of 400±5 g C m-2 yr-1 above which the population will suffer water shortages. NPP in this region is found to be already close to this limit.

  9. Groundwater quality in the Cascade Range and Modoc Plateau, California

    Science.gov (United States)

    Fram, Miranda S.; Shelton, Jennifer L.

    2015-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Cascade Range and Modoc Plateau area constitutes one of the study units being evaluated.

  10. Neoendemic ground beetles and private tree haplotypes: two independent proxies attest a moderate last glacial maximum summer temperature depression of 3-4 °C for the southern Tibetan Plateau

    Science.gov (United States)

    Schmidt, Joachim; Opgenoorth, Lars; Martens, Jochen; Miehe, Georg

    2011-07-01

    Previous findings regarding the Last Glacial Maximum LGM summer temperature depression (maxΔT in July) on the Tibetan Plateau varied over a large range (between 0 and 9 °C). Geologic proxies usually provided higher values than palynological data. Because of this wide temperature range, it was hitherto impossible to reconstruct the glacial environment of the Tibetan Plateau. Here, we present for the first time data indicating that local neoendemics of modern species groups are promising proxies for assessing the LGM temperature depression in Tibet. We used biogeographical and phylogenetic data from small, wingless edaphous ground beetles of the genus Trechus, and from private juniper tree haplotypes. The derived values of the maxΔT in July ranged between 3 and 4 °C. Our data support previous findings that were based on palynological data. At the same time, our data are spatially more specific as they are not bound to specific archives. Our study shows that the use of modern endemics enables a detailed mapping of local LGM conditions in High Asia. A prerequisite for this is an extensive biogeographical and phylogenetic exploration of the area and the inclusion of additional endemic taxa and evolutionary lines.

  11. Mixing on the Heard Island Plateau during HEOBI

    Science.gov (United States)

    Robertson, R.

    2016-12-01

    On the plateau near Heard and McDonald Islands, the water column was nearly always well mixed. Typically, temperature differences between the surface and the bottom, 100-200 m, were less than 0.2oC and often less that 0.1oC. Surface stratification developed through insolation and deep primarily through a combination of upwelling from canyons and over the edge of the plateau and tidal advection. This stratification was primarily removed by a combination of wind and tidal mixing. Persistent winds of 30 knots mixed the upper 20-50 m. Strong wind events, 40-60 knots, mixed the water column to 100-200 m depth, which over the plateau, was often the entire water column. Benthic tidal friction mixed the bottom 30-50 m. Although the water column was unstratified at the two plume sites intensively investigated, tidal velocities were baroclinic, probably due to topographic controls. Tidal advection changed the bottom temperatures by 0.5oC within 8 hours, more than doubling the prior stratification. Wind mixing quickly homogenized the water column, resulting in the surface often showing the deeper upwelling and advective events. Although acoustic plumes with bubbles were observed in the water column, there was no evidence of geothermal vents or geothermal influence on temperatures. Mixing by bubbles rising in the water column was indistinguishable from the wind and tidal mixing, although the strongest upward vertical velocities were observed at the sites of these acoustic/bubble plumes.

  12. Internal tides and vertical mixing over the Kerguelen Plateau

    Science.gov (United States)

    Park, Young-Hyang; Fuda, Jean-Luc; Durand, Isabelle; Naveira Garabato, Alberto C.

    2008-03-01

    Within the context of the natural iron-fertilization study KEOPS, time series measurements of CTD and LADCP profiles at a site (50.6°S, 72°E; 528 m) coinciding with an annual phytoplankton bloom over the Kerguelen Plateau were made during the January-February 2005 KEOPS cruise. An important activity of highly nonlinear semidiurnal internal tides having peak-to-peak isopycnal displacements of up to 80 m is identified. These internal tides appear to be a principal agent for promoting elevated vertical mixing indispensable for upward transfer of iron within the seasonal thermocline. We estimate local vertical eddy diffusivities of the order of 4×10 -4 m 2 s -1 using a Thorpe scale analysis. Although this estimate is higher by an order of magnitude than the canonical value O (0.1×10 -4 m 2 s -1) in the open ocean away from boundaries, it is consistent with nonlinear internal wave/wave interaction theories, as verified by independent diffusivity estimates using the vertical wavenumber spectral methods for shear and strain. It is also suggested that the general ocean circulation may play an important role in preconditioning the bloom in that the relatively sluggish circulation over the shallow plateau (compared to the much more dynamic neighbouring deep ocean) may foster the bloom's observed annual recurrence over the plateau.

  13. Black Carbon Radiative Forcing over the Tibetan Plateau

    Energy Technology Data Exchange (ETDEWEB)

    He, Cenlin; Li, Qinbin; Liou, K. N.; Takano, Y.; Gu, Yu; Qi, L.; Mao, Yuhao; Leung, Lai-Yung R.

    2014-11-28

    We estimate the snow albedo forcing and direct radiative forcing (DRF) of black carbon (BC) in the Tibetan Plateau using a global chemical transport model in conjunction with a stochastic snow model and a radiative transfer model. Our best estimate of the annual BC snow albedo forcing in the Plateau is 2.9 W m-2 (uncertainty: 1.5–5.0 W m-226 ). We find that BC-snow internal mixing increases the albedo forcing by 40-60% compared with external mixing and coated BC increases the forcing by 30-50% compared with uncoated BC, whereas Koch snowflakes reduce the forcing by 20-40% relative to spherical snow grains. Our best estimate of the annual BC DRF at the top of the atmosphere is 2.3 W m-2 (uncertainty: 0.7–4.3 W m-230 ) in the Plateau after scaling the modeled BC absorption optical depth to Aerosol Robotic Network (AERONET) observations. The BC forcings are attributed to emissions from different regions.

  14. Cenozoic mountain building on the northeastern Tibetan Plateau

    Science.gov (United States)

    Lease, Richard O.

    2014-01-01

    Northeastern Tibetan Plateau growth illuminates the kinematics, geodynamics, and climatic consequences of large-scale orogenesis, yet only recently have data become available to outline the spatiotemporal pattern and rates of this growth. I review the tectonic history of range growth across the plateau margin north of the Kunlun fault (35°–40°N) and east of the Qaidam basin (98°–107°E), synthesizing records from fault-bounded mountain ranges and adjacent sedimentary basins. Deformation began in Eocene time shortly after India-Asia collision, but the northeastern orogen boundary has largely remained stationary since this time. Widespread middle Miocene–Holocene range growth is portrayed by accelerated deformation, uplift, erosion, and deposition across northeastern Tibet. The extent of deformation, however, only expanded ~150 km outward to the north and east and ~150 km laterally to the west. A middle Miocene reorganization of deformation characterized by shortening at various orientations heralds the onset of the modern kinematic regime where shortening is coupled to strike slip. This regime is responsible for the majority of Cenozoic crustal shortening and thickening and the development of the northeastern Tibetan Plateau.

  15. Path of Social Construction in Northwest Sichuan Plateau Pastoral Area

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    On the basis of main contents of social construction and key points of construction,this paper analyzes features of conditions of northwest Sichuan plateau pastoral area.The social construction at current stage mainly includes social cause in narrow sense,and social management at meso-level.The northwest Sichuan plateau pastoral area is faced with the best policy and development opportunity.However,there are still many weak aspects.Firstly,social structure is not coordinated with economic structure.Secondly,social construction ability of grass-roots government is weak.Thirdly,the ability to respond to public demands is low.Fourthly,there is a big gap in availability of basic public service.Finally,it presents path selection for social construction of northwest Sichuan plateau pastoral area:strengthen social construction ability of grass-roots government;promote social construction with livelihood projects as key projects;boost social construction taking advantage of ecological construction;develop basic public service with the aid of external forces;intensify evaluation system for supervision of social construction works.

  16. Plateau inflation in R-parity violating MSSM

    Directory of Open Access Journals (Sweden)

    Girish Kumar Chakravarty

    2016-12-01

    Full Text Available Inflation with plateau potentials give the best fit to the CMB observables as they predict tensor to scalar ratio stringently bounded by the observations from Planck and BICEP2/Keck. In supergravity models it is possible to obtain plateau potentials for scalar fields in the Einstein frame which can serve as the inflation potential by considering higher dimensional Planck suppressed operators and by the choice of non-canonical Kähler potentials. We construct a plateau inflation model in MSSM where the inflation occurs along a sneutrino-Higgs flat direction. A hidden sector Polonyi field is used for the breaking of supersymmetry after the end of the inflation. The proper choice of superpotential leads to strong stabilization of the Polonyi field, mZ2≫m3/22, which is required to solve the cosmological moduli problem. Also, the SUSY breaking results in a TeV scale gravitino mass and scalar masses and gives rise to bilinear and trilinear couplings of scalars which can be tested at the LHC. The sneutrino inflation field can be observed at the LHC as a TeV scale diphoton resonance like the one reported by CMS and ATLAS.

  17. Diversity and Ecology of Dendrobiums (Orchidaceae in Chotanagpur Plateau, India

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar

    2011-03-01

    Full Text Available As part of All India Coordinated Research Project on Taxonomy of orchids (AICOPTAX Chotanagpur Plateau was surveyed extensively for documentation of orchid species and distribution during 2002 -2006. Sixty three species were collected from the study area with Dendrobium as one of the largest group of epiphytic orchids comprising of 11 species, namely, Dendrobium aphyllum, D. bicameratum, D. cucullatum, D. crepidatum, D. formosum, D. fimbriatum, D. herbaceum, D. moschatum, D. peguanum, D. regium and D. transparens. Most of the species were found in the Sal (Shorea robusta dominated forests. Stratified Random Sampling was used for ecological studies in the forested regions on the plateau. Results show that D. aphyllum was the most common amongst 11 species and it was distributed through out the altitudinal gradient, whereas, rest of the orchid species were found to be localised at comparatively higher altitudes. D. herbaceum was always found on the upper areas of the plateaus between 900-1000 m asl. D. crepidatum was seen in both epiphytic as well as lithophytic conditions, whereas D. moschatum were found growing as lithophytes along the streams. Rest of the species were epithytic. The paper also deals some microhabitat features governing the distribution of these orchids on the plateau along with their key for identification.

  18. Activity budget and behavioural patterns of Gelada Theropithecus gelada (Mammalia: Primates: Cercopithecidae on the Gich Plateau of the Simien Mountains National Park, Ethiopia

    Directory of Open Access Journals (Sweden)

    Cherkos Woldegeorgis

    2015-06-01

    Full Text Available The time budget and behavioural patterns of Gelada were studied on the Gich Plateau of the Simien Mountains National Park, Ethiopia.  The plateau is dominated mainly by Afroalpine grasses and the endemic giant Lobelia rhynchopetalum.  Gich lies on the climatic and altitudinal limits of the Gelada’s geographical distribution.  Activity data were collected using continuous focal animal scan sampling method during 10 consecutive days each month (from May 2013 to April 2014.  Data were recorded for different age/sex classes.  The Gelada spent on average 56.7% of daylight hours feeding, 14.1% travelling, 10.7% resting, 17.5% socializing and 1.1% in other non-social activity.  There was seasonal variation in activity budgets, indicating a significant increase in time allocation for feeding activity, but a decrease in resting time during the dry season.  The age/sex classes showed variation in activity budgets, except for social activity.  

  19. Effects of natural phenomena and human activity on the species richness of endemic and non-endemic Heteroptera in the Canary Islands

    Directory of Open Access Journals (Sweden)

    Vargas, J. M.

    2004-12-01

    Full Text Available The geographical patterns of Heteroptera species diversity in the Canary Islands were analysed, and endemic and non–endemic species were studied both together and separately. Causal processes most likely controlling these patterns, as well as the theory of island biogeography, hypotheses about evolutionary time, habitat heterogeneity, climatic stability, intermediate disturbances, energy, environmental favourableness–severity, productivity and human influence were investigated. The combination of habitat heterogeneity and human influence accounted for the total number of species. However, when endemic and non–endemic species were analysed separately, habitat heterogeneity and favourableness–severity explained the richness of endemic species, whereas habitat heterogeneity and human influence explained that of non–endemic species.

  20. Influence of Western Tibetan Plateau Summer Snow Cover on East Asian Summer Rainfall

    Science.gov (United States)

    Wang, Zhibiao; Wu, Renguang; Chen, Shangfeng; Huang, Gang; Liu, Ge; Zhu, Lihua

    2018-03-01

    The influence of boreal winter-spring eastern Tibetan Plateau snow anomalies on the East Asian summer rainfall variability has been the focus of previous studies. The present study documents the impacts of boreal summer western and southern Tibetan Plateau snow cover anomalies on summer rainfall over East Asia. Analysis shows that more snow cover in the western and southern Tibetan Plateau induces anomalous cooling in the overlying atmospheric column. The induced atmospheric circulation changes are different corresponding to more snow cover in the western and southern Tibetan Plateau. The atmospheric circulation changes accompanying the western Plateau snow cover anomalies are more obvious over the midlatitude Asia, whereas those corresponding to the southern Plateau snow cover anomalies are more prominent over the tropics. As such, the western and southern Tibetan Plateau snow cover anomalies influence the East Asian summer circulation and precipitation through different pathways. Nevertheless, the East Asian summer circulation and precipitation anomalies induced by the western and southern Plateau snow cover anomalies tend to display similar distribution so that they are more pronounced when the western and southern Plateau snow cover anomalies work in coherence. Analysis indicates that the summer snow cover anomalies over the Tibetan Plateau may be related to late spring snow anomalies due to the persistence. The late spring snow anomalies are related to an obvious wave train originating from the western North Atlantic that may be partly associated with sea surface temperature anomalies in the North Atlantic Ocean.

  1. On the origin of endemic species in the Red Sea

    KAUST Repository

    DiBattista, Joseph; Howard Choat, J.; Gaither, Michelle R.; Hobbs, Jean-Paul A.; Lozano-Corté s, Diego; Myers, Robert F.; Paulay, Gustav; Rocha, Luiz A.; Toonen, Robert J.; Westneat, Mark W.; Berumen, Michael L.

    2015-01-01

    High endemism observed in the Red Sea and Gulf of Aden appears to have multiple origins. A cold, nutrient-rich water barrier separates the Gulf of Aden from the rest of the Arabian Sea, whereas a narrow strait separates the Red Sea from the Gulf of Aden, each providing potential isolating barriers. Additional barriers may arise from environmental gradients, circulation patterns and the constriction at the mouth of the Gulf of Aqaba. Endemics that evolved within the Red Sea basin had to survive glacial cycles in relatively low salinity refugia. It therefore appears that the unique conditions in the Red Sea, in addition to those characteristics of the Arabian Peninsula region as a whole, drive the divergence of populations via a combination of isolation and selection.

  2. Responses to TRH in patients with endemic goiter

    International Nuclear Information System (INIS)

    Carneiro, Laureano; Watanabe, Tomas; El Tamer, Elias; Varela, Amalia; Moran, Dardo; Rinaudo, Antonio; Staneloni, Luis; Degrossi, O.J.

    1978-12-01

    The response to TRH was studied in 32 patients from an endemic goiter area, 20 of them had been previously treated with iodized oil. Blood samples were taken at 0, 20, 40 and 120 minutes after de i.v. administration of 400μg of TRH, and serum levels of TSH, T3 and T4 were measured. The results obtained show that in endemic goiter area there is a modification in the hypothalamus-pituitary-thyroid feedback mechanism, with increased reserve of pituitary TSH and changes in T4 and T3 secretion. The injection of TRH gave exaggerated and delayed responses in the secretion of TSH and T3. Iodized oil used as a prophylatic method produced a disminution of pituitary TSH reserve, and of serum levels of TSH and T3, as a result of the return tonormality of the hypothalamus-pituitary-thyroid feedback mechanism. (author) [es

  3. Plateau iris Íris em platô

    Directory of Open Access Journals (Sweden)

    Alberto Diniz Filho

    2008-10-01

    Full Text Available The term plateau iris was first coined in 1958 to describe the iris configuration of a patient. Two years later the concept of plateau iris was published. In 1977, the plateau iris configuration was classically defined as presurgical changes of an eye with a relative normal central anterior chamber depth, flat iris by conventional biomicroscopy, but displaying an extremely narrow or closed angle on gonioscopic examination. On the other hand, the plateau iris syndrome was defined as an acute glaucoma crisis in one eye with a relative normal central anterior chamber depth and patent iridotomy on direct examination, presenting angle closure confirmed by gonioscopic examination after mydriasis. In 1992, the anatomic aspects of plateau iris were studied using ultrasound biomicroscopy. Finally, plateau iris has been considered an anatomic variant of iris structure in which the iris periphery angulates sharply forward from its insertion point and then again angulates sharply and centrally backward, along with an anterior positioning of the ciliary processes seen on ultrasound biomicroscopy. The clinical treatment of plateau iris syndrome is carried out with topical use of pilocarpine. However, the definitive treatment should be fulfilled by performing an argon laser peripheral iridoplasty.O termo íris em platô foi primeiramente inventado em 1958 para descrever a configuração da íris de um paciente. Dois anos depois o conceito de íris em platô foi publicado. Em 1977, a configuração de íris em platô foi classicamente definida como alterações pré-cirúrgicas de um olho com uma profundidade de câmara anterior relativamente normal, íris plana pela biomicroscopia convencional, mas mostrando um ângulo extremamente estreito ou fechado pela gonioscopia. Por outro lado, a síndrome de íris em platô foi definida como uma crise de glaucoma agudo em um olho com uma profundidade de câmara anterior relativamente normal e uma iridectomia patente ao

  4. Early Human Occupation on the Northeast Tibetan Plateau

    Science.gov (United States)

    Rhode, D.; Madsen, D.; Brantingham, P.; Perrault, C.

    2010-12-01

    The Tibetan Plateau presents great challenges for human occupation: low oxygen, high ultraviolet radiation, harsh seasonal climate, low overall biological productivity. How and when early humans were able to cope physiologically, genetically, and behaviorally with these extremes is important for understanding the history of human adaptive flexibility. Our investigations of prehistoric human settlement on the northeast Tibetan Plateau focus on (a) establishing well-dated evidence for occupation of altitudes >3000 m, (b) the environmental context of high altitude adaptation, and (c) relations of hunting and pastoralism to lower-altitude agrarian systems. We observe two major prehistoric settlement patterns in the Qinghai Lake area. The earliest, ~15,000-7500 yr old, consists of small isolated firehearths with sparse associated stone tools and wild mammal remains (1). Numerous hearths often occur in the same localities, indicating repeated short-duration occupations by small hunting parties. A second pattern, ~9000-4000 yr old, was established during the Holocene climatic optimum. These sites represent prolonged seasonal residential occupation, containing dark anthropogenic midden, hearth and pit constructions, abundant stone tools, occasional ceramics, and abundant diverse faunal remains (including medium-large mammals but lacking domestic sheep/yak)(2). These Plateau-margin base camps allowed greater intensity of use of the high Plateau. Residential occupation was strongly influenced by nearby lower-altitude farming communities; development of the socioeconomic landscape along the Yellow River likely played at least as great a role in Plateau occupation patterns as did Holocene environmental changes. Holocene vegetation changes in the NE Tibetan Plateau have been attributed to climate (3) or anthropogenic modification (4). Our results document changes in shrub/tree presence from ~12,000-4000 BP, similar to pollen records, that likely reflect climate rather than

  5. Patterns of Freshwater Species Richness, Endemism, and Vulnerability in California.

    Directory of Open Access Journals (Sweden)

    Jeanette K Howard

    Full Text Available The ranges and abundances of species that depend on freshwater habitats are declining worldwide. Efforts to counteract those trends are often hampered by a lack of information about species distribution and conservation status and are often strongly biased toward a few well-studied groups. We identified the 3,906 vascular plants, macroinvertebrates, and vertebrates native to California, USA, that depend on fresh water for at least one stage of their life history. We evaluated the conservation status for these taxa using existing government and non-governmental organization assessments (e.g., endangered species act, NatureServe, created a spatial database of locality observations or distribution information from ~400 data sources, and mapped patterns of richness, endemism, and vulnerability. Although nearly half of all taxa with conservation status (n = 1,939 are vulnerable to extinction, only 114 (6% of those vulnerable taxa have a legal mandate for protection in the form of formal inclusion on a state or federal endangered species list. Endemic taxa are at greater risk than non-endemics, with 90% of the 927 endemic taxa vulnerable to extinction. Records with spatial data were available for a total of 2,276 species (61%. The patterns of species richness differ depending on the taxonomic group analyzed, but are similar across taxonomic level. No particular taxonomic group represents an umbrella for all species, but hotspots of high richness for listed species cover 40% of the hotspots for all other species and 58% of the hotspots for vulnerable freshwater species. By mapping freshwater species hotspots we show locations that represent the top priority for conservation action in the state. This study identifies opportunities to fill gaps in the evaluation of conservation status for freshwater taxa in California, to address the lack of occurrence information for nearly 40% of freshwater taxa and nearly 40% of watersheds in the state, and to

  6. Control and eradication of endemic infectious diseases in cattle

    DEFF Research Database (Denmark)

    Houe, Hans; Nielsen, Liza Rosenbaum; Nielsen, Søren Saxmose

    "Control and eradication of endemic infectious diseases in cattle" provides the key elements that should be addressed in the establishment of bovine disease control and eradication programmes. The book aims to reach a broad group of readers, including: students; professionals in veterinary practice...... "disease profiling", which is governed by the characteristics of the agent and its interaction with the host and environment. This profile, along with due consideration of the socioeconomic circumstances, can be used to determine how best to address the problem....

  7. Mitogenomic phylogeny of cone snails endemic to Senegal.

    Science.gov (United States)

    Abalde, Samuel; Tenorio, Manuel J; Afonso, Carlos M L; Zardoya, Rafael

    2017-07-01

    Cone snails attain in Senegal one of their highest peaks of species diversity throughout the continental coast of Western Africa. A total of 15 endemic species have been described, all placed in the genus Lautoconus. While there is ample data regarding the morphology of the shell and the radular tooth of these species, virtually nothing is known regarding the genetic diversity and phylogenetic relationships of one of the most endangered groups of cones. In this work, we determined the complete or near-complete (only lacking the control region) mitochondrial (mt) genomes of 17 specimens representing 11 endemic species (Lautoconus belairensis, Lautoconus bruguieresi, Lautoconus cacao, Lautoconus cloveri, Lautoconus cf. echinophilus, Lautoconus guinaicus, Lautoconus hybridus, Lautoconus senegalensis, Lautoconus mercator, Lautoconus taslei, and Lautoconus unifasciatus). We also sequenced the complete mt genome of Lautoconus guanche from the Canary Islands, which has been related to the cones endemic to Senegal. All mt genomes share the same gene arrangement, which conforms to the consensus reported for Conidae, Neogastropoda and Caenogastropoda. Phylogenetic analyses using probabilistic methods recovered three major lineages, whose divergence coincided in time with sea level and ocean current changes as well as temperature fluctuations during the Messinian salinity crisis and the Plio-Pleistocene transition. Furthermore, the three lineages corresponded to distinct types of radular tooth (robust, small, and elongated), suggesting that dietary specialization could be an additional evolutionary driver in the diversification of the cones endemic to Senegal. The reconstructed phylogeny showed several cases of phenotypic convergence (cryptic species) and questions the validity of some species (ecotypes or phenotypic plasticity), both results having important taxonomic and conservation consequences. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Biogeographical note on Antarctic microflorae: Endemism and cosmopolitanism

    Directory of Open Access Journals (Sweden)

    Waqar Azeem Jadoon

    2013-11-01

    Full Text Available This study deals with the biogeography of Antarctic microflora (Antarctica acts as best model to study microbial biogeography such as cyanobacteria and selected halophiles with special emphasis on Halomonas variabilis and Bacillus licheniformis. Halophiles are known to be resistant not only to salt stress, but also to extreme temperature, pressure, and aridity and they are capable of surviving in harsh environments such as polar regions, deep-sea habitats, and deserts. Many microbes are known to be resistant to hostile environmental conditions, and are capable of surviving in harsh environments. Our group has isolated 444 strains belonging to 28 genera of halophiles from various environments around the world. The 16S rRNA gene sequences revealed that many of the isolated strains from geographically distant habitats having different environmental conditions, were closely related to each other, with some strains possessing 100% identical sequences. Organisms possessing survival mechanism such as spore formation are usually ubiquitous. The genus Halomonas is represented by potentially endemic strains and the ubiquitous H. variabilis, while spore-forming B. licheniformis showed cosmopolitan distribution. One potentially endemic (moderate endemicity that is regional and/or continental distribution strain was reported from Syowa station, East Antarctica, and Mario Zucchelli station, West Antarctica, which are geographically separated by 3000 km. Moreover, 15 strains having 100% similarity with B. licheniformis were considered cosmopolitans. The results of this work provide support for the middle-ground model that some microbes have moderate endemicity and others have cosmopolitan distribution. These results will contribute to a greater understanding of microbial biogeography with special emphasis on Antarctica.

  9. [Endemic situation and control progress of taeniasis in western China].

    Science.gov (United States)

    Long, Chang-Ping; Qian, Ying-Jun; Li, Tiao-Ying; Fu, Qing; Wang, Qiang; Xiao, Ning

    2014-06-01

    Taeniasis, caused by Taenia species, is one of the common zoonoses in China, particularly in the western region of China. Up to now, not enough attention has been given in the high prevalence and high burden of the diseases. In order to study the endemic patterns and control strategies of taeniasis, a series of epidemiological investigations, molecular researches and pilot control activities have been conducted in recent years. This paper reviews the relevant publications in taeniasis research over the last 10 years.

  10. Evolution of endemism on a young tropical mountain.

    Science.gov (United States)

    Merckx, Vincent S F T; Hendriks, Kasper P; Beentjes, Kevin K; Mennes, Constantijn B; Becking, Leontine E; Peijnenburg, Katja T C A; Afendy, Aqilah; Arumugam, Nivaarani; de Boer, Hugo; Biun, Alim; Buang, Matsain M; Chen, Ping-Ping; Chung, Arthur Y C; Dow, Rory; Feijen, Frida A A; Feijen, Hans; Feijen-van Soest, Cobi; Geml, József; Geurts, René; Gravendeel, Barbara; Hovenkamp, Peter; Imbun, Paul; Ipor, Isa; Janssens, Steven B; Jocqué, Merlijn; Kappes, Heike; Khoo, Eyen; Koomen, Peter; Lens, Frederic; Majapun, Richard J; Morgado, Luis N; Neupane, Suman; Nieser, Nico; Pereira, Joan T; Rahman, Homathevi; Sabran, Suzana; Sawang, Anati; Schwallier, Rachel M; Shim, Phyau-Soon; Smit, Harry; Sol, Nicolien; Spait, Maipul; Stech, Michael; Stokvis, Frank; Sugau, John B; Suleiman, Monica; Sumail, Sukaibin; Thomas, Daniel C; van Tol, Jan; Tuh, Fred Y Y; Yahya, Bakhtiar E; Nais, Jamili; Repin, Rimi; Lakim, Maklarin; Schilthuizen, Menno

    2015-08-20

    Tropical mountains are hot spots of biodiversity and endemism, but the evolutionary origins of their unique biotas are poorly understood. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these communities. Also, it is debated whether mountain endemics mostly originate from local lowland taxa, or from lineages that reach the mountain by long-range dispersal from cool localities elsewhere. Here we investigate the evolutionary routes to endemism by sampling an entire tropical mountain biota on the 4,095-metre-high Mount Kinabalu in Sabah, East Malaysia. We discover that most of its unique biodiversity is younger than the mountain itself (6 million years), and comprises a mix of immigrant pre-adapted lineages and descendants from local lowland ancestors, although substantial shifts from lower to higher vegetation zones in this latter group were rare. These insights could improve forecasts of the likelihood of extinction and 'evolutionary rescue' in montane biodiversity hot spots under climate change scenarios.

  11. Recovery of endemic dragonflies after removal of invasive alien trees.

    Science.gov (United States)

    Samways, Michael J; Sharratt, Norma J

    2010-02-01

    Because dragonflies are very sensitive to alien trees, we assessed their response to large-scale restoration of riparian corridors. We compared three types of disturbance regime--alien invaded, cleared of alien vegetation, and natural vegetation (control)--and recorded data on 22 environmental variables. The most significant variables in determining dragonfly assemblages were percentage of bank cover and tree canopy cover, which indicates the importance of vegetation architecture for these dragonflies. This finding suggests that it is important to restore appropriate marginal vegetation and sunlight conditions. Recovery of dragonfly assemblages after the clearing of alien trees was substantial. Species richness and abundance at restored sites matched those at control sites. Dragonfly assemblage patterns reflected vegetation succession. Thus, initially eurytopic, widespread species were the main beneficiaries of the removal of alien trees, and stenotopic, endemic species appeared after indigenous vegetation recovered over time. Important indicator species were the two national endemics (Allocnemis leucosticta and Pseudagrion furcigerum), which, along with vegetation type, can be used to monitor return of overall integrity of riparian ecology and to make management decisions. Endemic species as a whole responded positively to restoration, which suggests that indigenous vegetation recovery has major benefits for irreplaceable and widespread generalist species.

  12. Transcriptome profile and unique genetic evolution of positively selected genes in yak lungs.

    Science.gov (United States)

    Lan, DaoLiang; Xiong, XianRong; Ji, WenHui; Li, Jian; Mipam, Tserang-Donko; Ai, Yi; Chai, ZhiXin

    2018-04-01

    The yak (Bos grunniens), which is a unique bovine breed that is distributed mainly in the Qinghai-Tibetan Plateau, is considered a good model for studying plateau adaptability in mammals. The lungs are important functional organs that enable animals to adapt to their external environment. However, the genetic mechanism underlying the adaptability of yak lungs to harsh plateau environments remains unknown. To explore the unique evolutionary process and genetic mechanism of yak adaptation to plateau environments, we performed transcriptome sequencing of yak and cattle (Bos taurus) lungs using RNA-Seq technology and a subsequent comparison analysis to identify the positively selected genes in the yak. After deep sequencing, a normal transcriptome profile of yak lung that containing a total of 16,815 expressed genes was obtained, and the characteristics of yak lungs transcriptome was described by functional analysis. Furthermore, Ka/Ks comparison statistics result showed that 39 strong positively selected genes are identified from yak lungs. Further GO and KEGG analysis was conducted for the functional annotation of these genes. The results of this study provide valuable data for further explorations of the unique evolutionary process of high-altitude hypoxia adaptation in yaks in the Tibetan Plateau and the genetic mechanism at the molecular level.

  13. Spiny Neurons of Amygdala, Striatum and Cortex Use Dendritic Plateau Potentials to Detect Network UP States

    Directory of Open Access Journals (Sweden)

    Katerina D Oikonomou

    2014-09-01

    Full Text Available Spiny neurons of amygdala, striatum, and cerebral cortex share four interesting features: [1] they are the most abundant cell type within their respective brain area, [2] covered by thousands of thorny protrusions (dendritic spines, [3] possess high levels of dendritic NMDA conductances, and [4] experience sustained somatic depolarizations in vivo and in vitro (UP states. In all spiny neurons of the forebrain, adequate glutamatergic inputs generate dendritic plateau potentials (dendritic UP states characterized by (i fast rise, (ii plateau phase lasting several hundred milliseconds and (iii abrupt decline at the end of the plateau phase. The dendritic plateau potential propagates towards the cell body decrementally to induce a long-lasting (longer than 100 ms, most often 200 – 800 ms steady depolarization (~20 mV amplitude, which resembles a neuronal UP state. Based on voltage-sensitive dye imaging, the plateau depolarization in the soma is precisely time-locked to the regenerative plateau potential taking place in the dendrite. The somatic plateau rises after the onset of the dendritic voltage transient and collapses with the breakdown of the dendritic plateau depolarization. We hypothesize that neuronal UP states in vivo reflect the occurrence of dendritic plateau potentials (dendritic UP states. We propose that the somatic voltage waveform during a neuronal UP state is determined by dendritic plateau potentials. A mammalian spiny neuron uses dendritic plateau potentials to detect and transform coherent network activity into a ubiquitous neuronal UP state. The biophysical properties of dendritic plateau potentials allow neurons to quickly attune to the ongoing network activity, as well as secure the stable amplitudes of successive UP states.

  14. Timing and mechanism of the rise of the Shillong Plateau in the Himalayan foreland.

    OpenAIRE

    Govin, Gwladys; Najman, Yanina Manya Rachel; Copley, Alex; Millar, Ian; Van der Beek, Peter; Huyghe, Pascale; Grujic, Djordje; Davenport, Jesse

    2018-01-01

    The Shillong Plateau (northeastern India) constitutes the only significant topography in the Himalayan foreland. Knowledge of its surface uplift history is key to understanding topographic development and unraveling tectonic–climate–topographic coupling in the eastern Himalaya. We use the sedimentary record of the Himalayan foreland basin north of the Shillong Plateau to show that the paleo-Brahmaputra river was redirected north and west by the rising plateau at 5.2–4.9 Ma. We suggest that on...

  15. A preliminary study of the heating effect of the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Yonghui Yao

    Full Text Available The immense and towering Tibetan Plateau acts as a heating source and, thus, deeply shapes the climate of the Eurasian continent and even the whole world. However, due to the scarcity of meteorological observation stations and very limited climatic data, little is quantitatively known about the heating effect of the plateau and its implications. This paper firstly collects climate data (2001-2007 from 109 observation stations and MODIS-based estimated monthly mean temperature data in the plateau and the neighboring Sichuan Basin, and conducts correlation and simple linear regression to reveal the altitudinal pattern of temperature. Then, according to the linear relationships of temperature and altitude for each month, it compares air temperature differences on the same elevation between the main plateau and surrounding mountains and the Sichuan Basin so as to quantify the heating effect and discuss its implication on timberline of the plateau. The results show that: 1 the heating effect of the plateau is significant. The temperature of the main plateau area was higher than that of free air on the same elevation above the neighboring areas; on the elevation of 4500 m (the main plateau, temperature is 1-6°C higher in the main Plateau than over the Sichuan Basin for different months and 5.9-10.7°C higher than in the Qilian Mountains in the northeastern corner of the plateau. 2 Even at altitudes of 5000-6000 m in the main Plateau, there are 4 months with a mean temperature above 0°C. The mean temperature of the warmest month (July can reach 10°C at about 4600-4700 m. This may help explain why the highest timberline in the northern hemisphere is on the southeastern Tibetan Plateau.

  16. Composition, Endemism and Phytogeographical Affinities of the Taiwan Flora

    Directory of Open Access Journals (Sweden)

    Chang-Fu Hsieh

    2002-12-01

    Full Text Available The Taiwan vascular flora is exceptionally interesting not only because it is rich and diversified, but because it is of great phytogeographic significance owing to its geographic location. The flora of Taiwan, including naturalized plants, comprises 233 families and 1389 genera with 4216 species. In terms of major growth forms, there are 588 trees, 426 shrubs, 249 lianas, 177 vines, and 2776 herbs or ferns. Approximately 234 species are exotics typically associated with pastures, road clearings and other human disturbances. An extremely large percentage of these naturalized plants are of tropical New World origin. Among the native flora, the Orchidaceae (331 species, Gramineae (249, Compositae (194, Leguminosae (176, Cyperaceae (174, Rosaceae (105, Rubiaceae (93 and Euphorbiaceae (76 rank highest in numbers of species. Clearly, the greatest part of Taiwan's floristics richness comes from a wealth of species in primarily lowland (0–600 m asl. taxa. A total of 2571 species were recorded in the lowlands, whereas only about 251 species occur between 3100-3950 m. Endemic genera are extremely scarce in Taiwan, with only four, namely Sinopanax (Araliaceae, Hayatella (Rubiaceae, Kudoacanthus (Acanthaceae, and Haraella (Orchidaceae. In contrast to the low percentage of generic endemism, there is a remarkably higher specific endemism. About 1041 species (26.1% of indigenous plants are known only from Taiwan. A detailed examination of these species shows that there is a distinct trend of increasing endemism with increasing altitude (r² = 0.99. A survey of indigenous non-endemic species on the basis of their geographical distribution outside Taiwan shows that they can be classified into 6 major categories: 1. pantropical and palaeotropical species (1029 species; 2. species distributed in eastern Asia, from Himalayas through southern & eastern China to Taiwan, with some extending to the Ryukyus and Japan (1075 species; 3. widespread species extending

  17. Medial tibial plateau morphology and stress fracture location: A magnetic resonance imaging study.

    Science.gov (United States)

    Yukata, Kiminori; Yamanaka, Issei; Ueda, Yuzuru; Nakai, Sho; Ogasa, Hiroyoshi; Oishi, Yosuke; Hamawaki, Jun-Ichi

    2017-06-18

    To determine the location of medial tibial plateau stress fractures and its relationship with tibial plateau morphology using magnetic resonance imaging (MRI). A retrospective review of patients with a diagnosis of stress fracture of the medial tibial plateau was performed for a 5-year period. Fourteen patients [three female and 11 male, with an average age of 36.4 years (range, 15-50 years)], who underwent knee MRI, were included. The appearance of the tibial plateau stress fracture and the geometry of the tibial plateau were reviewed and measured on MRI. Thirteen of 14 stress fractures were linear, and one of them stellated on MRI images. The location of fractures was classified into three types. Three fractures were located anteromedially (AM type), six posteromedially (PM type), and five posteriorly (P type) at the medial tibial plateau. In addition, tibial posterior slope at the medial tibial plateau tended to be larger when the fracture was located more posteriorly on MRI. We found that MRI showed three different localizations of medial tibial plateau stress fractures, which were associated with tibial posterior slope at the medial tibial plateau.

  18. Posterior Slope of the Tibia Plateau in Malaysian Patients Undergoing Total Knee Replacement

    Directory of Open Access Journals (Sweden)

    R Yoga

    2009-05-01

    Full Text Available The posterior slope of the tibial plateau is an important feature to preserve during knee replacement. The correct slope aids in the amount of flexion and determines if the knee will be loose on flexion. This is a study on the posterior tibial plateau slope based on preoperative and postoperative radiographs of 100 consecutive patients who had total knee replacements. The average posterior slope of the tibia plateau was 10.1 degrees. There is a tendency for patients with higher pre-operative posterior tibial plateau slope to have higher post-operative posterior tibial plate slope.

  19. FINAL FRONTIER AT HANFORD TACKLING THE CENTRAL PLATEAU

    International Nuclear Information System (INIS)

    GERBER MS

    2008-01-01

    The large land area in the center of the vast Department of Energy (DOE) Hanford Site in southeast Washington State is known as 'the plateau'--aptly named because its surface elevations are 250-300 feet above the groundwater table. By contrast, areas on the 585-square mile Site that border the Columbia River sit just 30-80 feet above the water table. The Central Plateau, which covers an ellipse of approximately 70 square miles, contains Hanford's radiochemical reprocessing areas--the 200 East and 200 West Areas--and includes the most highly radioactive waste and contaminated facilities on the Site. Five 'canyons' where chemical processes were used to separate out plutonium (Pu), 884 identified soil waste sites (including approximately 50 miles of solid waste burial trenches), more than 900 structures, and all of Hanford's liquid waste storage tanks reside in the Central Plateau. (Notes: Canyons is a nickname given by Hanford workers to the chemical reprocessing facilities. The 177, underground waste tanks at Hanford comprise a separate work scope and are not under Fluor's management). Fluor Hanford, a DOE prime cleanup contractor at the Site for the past 12 years, has moved aggressively to investigate Central Plateau waste sites in the last few years, digging more than 500 boreholes, test pits, direct soil 'pushes' or drive points; logging geophysical data sets; and performing electrical-resistivity scans (a non-intrusive technique that maps patterns of sub-surface soil conductivity). The goal is to identify areas of contamination areas in soil and solid waste sites, so that cost-effective and appropriate decisions on remediation can be made. In 2007, Fluor developed a new work plan for DOE that added 238 soil waste-site characterization activities in the Central Plateau during fiscal years (FYs) 2007-2010. This number represents a 50 percent increase over similar work previously done in central Hanford. Work Plans are among the required steps in the Comprehensive

  20. Re-evaluating the 1940s CO2 plateau

    Science.gov (United States)

    Bastos, Ana; Ciais, Philippe; Barichivich, Jonathan; Bopp, Laurent; Brovkin, Victor; Gasser, Thomas; Peng, Shushi; Pongratz, Julia; Viovy, Nicolas; Trudinger, Cathy M.

    2016-09-01

    The high-resolution CO2 record from Law Dome ice core reveals that atmospheric CO2 concentration stalled during the 1940s (so-called CO2 plateau). Since the fossil-fuel emissions did not decrease during the period, this stalling implies the persistence of a strong sink, perhaps sustained for as long as a decade or more. Double-deconvolution analyses have attributed this sink to the ocean, conceivably as a response to the very strong El Niño event in 1940-1942. However, this explanation is questionable, as recent ocean CO2 data indicate that the range of variability in the ocean sink has been rather modest in recent decades, and El Niño events have generally led to higher growth rates of atmospheric CO2 due to the offsetting terrestrial response. Here, we use the most up-to-date information on the different terms of the carbon budget: fossil-fuel emissions, four estimates of land-use change (LUC) emissions, ocean uptake from two different reconstructions, and the terrestrial sink modelled by the TRENDY project to identify the most likely causes of the 1940s plateau. We find that they greatly overestimate atmospheric CO2 growth rate during the plateau period, as well as in the 1960s, in spite of giving a plausible explanation for most of the 20th century carbon budget, especially from 1970 onwards. The mismatch between reconstructions and observations during the CO2 plateau epoch of 1940-1950 ranges between 0.9 and 2.0 Pg C yr-1, depending on the LUC dataset considered. This mismatch may be explained by (i) decadal variability in the ocean carbon sink not accounted for in the reconstructions we used, (ii) a further terrestrial sink currently missing in the estimates by land-surface models, or (iii) LUC processes not included in the current datasets. Ocean carbon models from CMIP5 indicate that natural variability in the ocean carbon sink could explain an additional 0.5 Pg C yr-1 uptake, but it is unlikely to be higher. The impact of the 1940-1942 El Niño on the

  1. The Evolution of Eastern Himalayan Syntaxis of Tibetan Plateau

    Science.gov (United States)

    Zhang, S.; Wu, T.; Li, M.; Zhang, Y.; Hua, Y.; Zhang, B.

    2017-12-01

    Indian plate has been colliding with Eurasian plate since 50Ma years ago, resulting in the Tethys extinction, crust shortening and Tibetan plateau uplift. But it is still a debate how the Tibetan Plateau material escaped. This study tries to invert the distributions of dispersion phase velocity and anisotropy in Eastern Himalayan Syntaxis (EHS) based on the seismic data. We focused on the seven sub-blocks around EHS region. Sub-block "EHS" represents EHS corner with high velocity anomalies, significantly compressed in the axle and strike directions. Sub-blocks "LSD", "QTB" and "SP-GZB" are located at its northern areas with compressions also, and connected with low-velocity anomalies in both crustal and upper mantle rocks. Sub-block "ICB" is located at its southern area with low velocity anomaly, and connected with Tengchong volcano. Sub-blocks "SYDB" and "YZB" are located at its eastern areas with high velocity anomalies in both crustal and upper mantle rocks. Our results demonstrated that significant azimuthal anisotropy of crust (t£30s) and upper mantle (30s£t£60s). Crustal anisotropy indicates the orogenic belt matched well with the direction of fast propagation, and upper mantle anisotropy represents the lattic-preferred orientation (LPO) of mantle minerals (e.g. olivine and basalt), indicating the features of subducting Indian plate. Besides, Red River fault is a dextral strike fault, controlling the crustal and mantle migration. There is a narrow zone to be the channel flow of Tibetan crustal materials escaping toward Yunnan area. The evolution of EHS seems constrained by gravity isostatic mechanism. Keywords: Tibetan Plateau; Eastern Himalayan Syntaxis; Red River fault; crustal flow; surface wave; anisotropy

  2. Prolonged operative time increases infection rate in tibial plateau fractures.

    Science.gov (United States)

    Colman, Matthew; Wright, Adam; Gruen, Gary; Siska, Peter; Pape, Hans-Christoph; Tarkin, Ivan

    2013-02-01

    Fractures of the tibial plateau present a treatment challenge and are susceptible to both prolonged operative times and high postoperative infection rates. For those fractures treated with open plating, we sought to identify the relationship between surgical site infection and prolonged operative time as well as to identify other surgical risk factors. We performed a retrospective controlled analysis of 309 consecutive unicondylar and bicondylar tibial plateau fractures treated with open plate osteosynthesis at our institution's level I trauma centre during a recent 5-year period. We recorded operative times, injury characteristics, surgical treatment, and need for operative debridement due to infection. Operative times of infected cases were compared to uncomplicated surgical cases. Multivariable logistic regression analysis was performed to identify independent risk factors for postoperative infection. Mean operative time in the infection group was 2.8h vs. 2.2h in the non-infected group (p=0.005). 15 fractures (4.9%) underwent four compartment fasciotomies as part of their treatment, with a significantly higher infection rate than those not undergoing fasciotomy (26.7% vs. 6.8%, p=0.01). Open fracture grade was also significantly related to infection rate (closed fractures: 5.3%, grade 1: 14.3%, grade 2: 40%, grade 3: 50%, pinfection rates (13.9% vs. 8.7%, p=0.36). Multivariable logistic regression analysis of the entire study group identified longer operative times (OR 1.78, p=0.013) and open fractures (OR 7.02, psite infection. Operative times approaching 3h and open fractures are related to an increased overall risk for surgical site infection after open plating of the tibial plateau. Dual incision approaches with bicolumnar plating do not appear to expose the patient to increased risk compared to single incision approaches. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Reconstructing plateau icefields: Evaluating empirical and modelled approaches

    Science.gov (United States)

    Pearce, Danni; Rea, Brice; Barr, Iestyn

    2013-04-01

    Glacial landforms are widely utilised to reconstruct former glacier geometries with a common aim to estimate the Equilibrium Line Altitudes (ELAs) and from these, infer palaeoclimatic conditions. Such inferences may be studied on a regional scale and used to correlate climatic gradients across large distances (e.g., Europe). In Britain, the traditional approach uses geomorphological mapping with hand contouring to derive the palaeo-ice surface. Recently, ice surface modelling enables an equilibrium profile reconstruction tuned using the geomorphology. Both methods permit derivation of palaeo-climate but no study has compared the two methods for the same ice-mass. This is important because either approach may result in differences in glacier limits, ELAs and palaeo-climate. This research uses both methods to reconstruct a plateau icefield and quantifies the results from a cartographic and geometrical aspect. Detailed geomorphological mapping of the Tweedsmuir Hills in the Southern Uplands, Scotland (c. 320 km2) was conducted to examine the extent of Younger Dryas (YD; 12.9 -11.7 cal. ka BP) glaciation. Landform evidence indicates a plateau icefield configuration of two separate ice-masses during the YD covering an area c. 45 km2 and 25 km2. The interpreted age is supported by new radiocarbon dating of basal stratigraphies and Terrestrial Cosmogenic Nuclide Analysis (TCNA) of in situ boulders. Both techniques produce similar configurations however; the model results in a coarser resolution requiring further processing if a cartographic map is required. When landforms are absent or fragmentary (e.g., trimlines and lateral moraines), like in many accumulation zones on plateau icefields, the geomorphological approach increasingly relies on extrapolation between lines of evidence and on the individual's perception of how the ice-mass ought to look. In some locations this results in an underestimation of the ice surface compared to the modelled surface most likely due to

  4. Population connectivity and the effectiveness of marine protected areas to protect vulnerable, exploited and endemic coral reef fishes at an endemic hotspot

    KAUST Repository

    Van Der Meer, Martin H.; Berumen, Michael L.; Hobbs, Jean Paul Adrian; Van Herwerden, Lynne Van

    2014-01-01

    -replenishment, and the absence of MPAs at NI needs to be rectified to ensure the persistence of endemic species at this location. Other endemic fishes exhibit similar patterns of high self-replenishment across the four locations, indicating that a single spatial management

  5. Soil carbon sequestration potential for "grain for green" project in Loess Plateau, China

    Science.gov (United States)

    Chang, R.; Fu, B.; Liu, Gaisheng; Liu, S.

    2011-01-01

    Conversion of cropland into perennial vegetation land can increase soil organic carbon (SOC) accumulation, which might be an important mitigation measure to sequester carbon dioxide from the atmosphere. The “Grain for Green” project, one of the most ambitious ecological programmes launched in modern China, aims at transforming the low-yield slope cropland into grassland and woodland. The Loess Plateau in China is the most important target of this project due to its serious soil erosion. The objectives of this study are to answer three questions: (1) what is the rate of the SOC accumulation for this “Grain for Green” project in Loess Plateau? (2) Is there a difference in SOC sequestration among different restoration types, including grassland, shrub and forest? (3) Is the effect of restoration types on SOC accumulation different among northern, middle and southern regions of the Loess Plateau? Based on analysis of the data collected from the literature conducted in the Loess Plateau, we found that SOC increased at a rate of 0.712 TgC/year in the top 20 cm soil layer for 60 years under this project across the entire Loess Plateau. This was a relatively reliable estimation based on current data, although there were some uncertainties. Compared to grassland, forest had a significantly greater effect on SOC accumulation in middle and southern Loess Plateau but had a weaker effect in the northern Loess Plateau. There were no differences found in SOC sequestration between shrub and grassland across the entire Loess Plateau. Grassland had a stronger effect on SOC sequestration in the northern Loess Plateau than in the middle and southern regions. In contrast, forest could increase more SOC in the middle and southern Loess Plateau than in the northern Loess Plateau, whereas shrub had a similar effect on SOC sequestration across the Loess Plateau. Our results suggest that the “Grain for Green” project can significantly increase the SOC storage in Loess Plateau

  6. Diversity distribution patterns of Chinese endemic seed plant species and their implications for conservation planning

    Science.gov (United States)

    Huang, Jihong; Huang, Jianhua; Lu, Xinghui; Ma, Keping

    2016-01-01

    Endemism is an important concept in biogeography and biodiversity conservation. China is one of the richest countries in biodiversity, with very high levels of plant endemism. In this study, we analysed the distribution patterns of diversity, the degree of differentiation, and the endemicity of Chinese endemic seed plants using the floristic unit as a basic spatial analysis unit and 11 indices. The analysis was based on distribution data of 24,951 native seed plant species (excluding subspecies and varieties) and 12,980 Chinese endemic seed plant species, which were sourced from both specimen records and published references. The distribution patterns of Chinese endemic flora were generally consistent but disproportionate across China for diversity, degree of differentiation and endemicity. The South Hengduan Mountains Subregion had the highest values for all indices. At the regional level, both the Hengduan Mountains and the Central China regions were highest in diversity and degrees of differentiation. However, both the rate of local endemic to native species and the rate of local to Chinese endemic species were highest in the Taiwan Region and the South Taiwan Region. The Hengduan Mountains Region and the Central China Region are two key conservation priority areas for Chinese endemic seed plants. PMID:27658845

  7. ANALYSIS OF ENDEMISM OF THE XEROPHILOUS FLORA IN THE RUSSIAN CAUCASUS

    Directory of Open Access Journals (Sweden)

    M. A. Taysumov

    2017-01-01

    Full Text Available The aim of our research is to study the endemics of the xerophilous flora of the Russian Caucasus in connection with the matter of knowing the genesis.Methods. The study is based on the field research expeditions.Findings. The presence of endemic species in flora is an indicator of its originality, and the degree of originality is determined by the extent of the endemic species. In general, according to our geographic analysis, the number of endemic species in xerophilous flora of the Russian Caucasus accounts for 32% (326 species, of which 25% of all endemic species have natural habitats within entire Caucasus, 66% are widespread in the Greater Caucasus, and 9% in the Pre-Caucasian region.Conclusion. Endemic species of xerophytes of the flora, in their overwhelming majority, are euxerophytes, and most steno-endemics also belong to this group of xerophytes. In a systematic aspect, the leading family, containing the largest number of endemic species, is Asteraceae (in percentage terms - Lamiaceae and Jurinea is a leading genus (in percentage terms - Psephellus. In relation to the substrate, calcixerophytes are the dominants and most saturated endemics in quantitative terms are the belt of mountain xerophytes. The predominant biomes are hemicryptophytes; as compared with the number of biomorphes, among chamaephytes there is the biggest quantity of endemics

  8. Evidence for endemic chikungunya virus infections in Bandung, Indonesia.

    Directory of Open Access Journals (Sweden)

    Herman Kosasih

    Full Text Available Chikungunya virus (CHIKV is known to cause sporadic or explosive outbreaks. However, little is known about the endemic transmission of CHIKV. To ascertain the endemic occurrence of CHIKV transmission, we tested blood samples from patients with a non-dengue febrile illness who participated in a prospective cohort study of factory workers in Bandung, Indonesia. From August 2000 to June 2004, and September 2006 to April 2008, 1901 febrile episodes occurred and 231 (12.2% dengue cases were identified. The remaining febrile cases were evaluated for possible CHIKV infection by measuring anti-CHIKV IgM and IgG antibodies in acute and convalescent samples. Acute samples of serologically positive cases were subsequently tested for the presence of CHIKV RNA by RT-PCR and/or virus isolation. A total of 135 (7.1% CHIKV infections were identified, providing an incidence rate of 10.1/1,000 person years. CHIKV infections were identified all year round and tended to increase during the rainy season (January to March. Severe illness was not found and severe arthralgia was not a prominently reported symptom. Serial post-illness samples from nine cases were tested to obtain a kinetic picture of IgM and IgG anti-CHIKV antibodies. Anti-CHIKV IgM antibodies were persistently detected in high titers for approximately one year. Three patients demonstrated evidence of possible sequential CHIKV infections. The high incidence rate and continuous chikungunya cases in this adult cohort suggests that CHIKV is endemically transmitted in Bandung. Further characterization of the circulating strains and surveillance in larger areas are needed to better understand CHIKV epidemiology in Indonesia.

  9. Is the endemic Maltese Top-shell Gibbula nivosa extinct?

    OpenAIRE

    Schembri, Patrick J.; Borg, Joseph A.; Deidun, Alan; Knittweis, Leyla; Mellado Lopez, T.

    2007-01-01

    The trochid gastropod Gibbula nivosa, endemic to the Maltese Islands, has recently only been found in two Maltese bays, where it occurred on seagrass leaves and under stones at depths of 1-4m. Intensive sampling of Cymodocea nodosa and Posidonia oceanica meadows, sediment and pebbles at depths of 2-12m, carried out in 2000 and 2002, resulted only in empty shells but no live animals, suggesting that the species is extinct from these localities where previously good populations were found. Howe...

  10. Studies to Control Endemic Typhoid Fever in Chile

    Science.gov (United States)

    1983-01-30

    Bol. Inst. Bacteriol. Chile 1976; 18:33-37. 30. Escaff, M, Urbina, A, Mary, J. Contaminacion de repollos regados con aguas servidas. Agricultura...Tecnica 1979; 39:59-62. - 31. Lobos, H, Greive, R, Quijada, M, Brandt, H. Pesquisa del genero Vibrio en aguas servidas. Bol. Inst. Bact. Chile 1974; 16:40...REPORT #2 0") STUDIES TO CONTROL ENDEMIC TYPHOID N FEVER IN CHILE 0) ANNUAL REPORT U’ Contract Period 1/1/82-12/31/82 • I REPORT PREPARED BY: L

  11. Endemic Sexual Violence and Abuse: Contexts and Dispositions

    Directory of Open Access Journals (Sweden)

    Susan Nicole Rayment-McHugh

    2015-07-01

    Full Text Available Endemic sexual violence and abuse has been observed in a number of specific circumstances, most notably conflict zones, remote and marginalised communities, and religious and state institutions. In this article we examine several documented examples and argue that a similar set of causal processes are at work in all of these otherwise apparently disparate circumstances. Rather than construing the problem as ‘organised’ sexual abuse, we present the problem in terms of the breakdown (or disorganisation of usual individual, situational and ecological constraints.

  12. Malaria in Brazil: what happens outside the Amazonian endemic region.

    Science.gov (United States)

    de Pina-Costa, Anielle; Brasil, Patrícia; Di Santi, Sílvia Maria; de Araujo, Mariana Pereira; Suárez-Mutis, Martha Cecilia; Santelli, Ana Carolina Faria e Silva; Oliveira-Ferreira, Joseli; Lourenço-de-Oliveira, Ricardo; Daniel-Ribeiro, Cláudio Tadeu

    2014-08-01

    Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation's territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation's malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013). The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon) or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex). The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites that seem to be (or

  13. Malaria in Brazil: what happens outside the Amazonian endemic region

    Directory of Open Access Journals (Sweden)

    Anielle de Pina-Costa

    2014-08-01

    Full Text Available Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation’s territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation’s malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013. The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex. The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites

  14. A new world malaria map: Plasmodium falciparum endemicity in 2010.

    Science.gov (United States)

    Gething, Peter W; Patil, Anand P; Smith, David L; Guerra, Carlos A; Elyazar, Iqbal R F; Johnston, Geoffrey L; Tatem, Andrew J; Hay, Simon I

    2011-12-20

    Transmission intensity affects almost all aspects of malaria epidemiology and the impact of malaria on human populations. Maps of transmission intensity are necessary to identify populations at different levels of risk and to evaluate objectively options for disease control. To remain relevant operationally, such maps must be updated frequently. Following the first global effort to map Plasmodium falciparum malaria endemicity in 2007, this paper describes the generation of a new world map for the year 2010. This analysis is extended to provide the first global estimates of two other metrics of transmission intensity for P. falciparum that underpin contemporary questions in malaria control: the entomological inoculation rate (PfEIR) and the basic reproductive number (PfR). Annual parasite incidence data for 13,449 administrative units in 43 endemic countries were sourced to define the spatial limits of P. falciparum transmission in 2010 and 22,212 P. falciparum parasite rate (PfPR) surveys were used in a model-based geostatistical (MBG) prediction to create a continuous contemporary surface of malaria endemicity within these limits. A suite of transmission models were developed that link PfPR to PfEIR and PfR and these were fitted to field data. These models were combined with the PfPR map to create new global predictions of PfEIR and PfR. All output maps included measured uncertainty. An estimated 1.13 and 1.44 billion people worldwide were at risk of unstable and stable P. falciparum malaria, respectively. The majority of the endemic world was predicted with a median PfEIR of less than one and a median PfRc of less than two. Values of either metric exceeding 10 were almost exclusive to Africa. The uncertainty described in both PfEIR and PfR was substantial in regions of intense transmission. The year 2010 has a particular significance as an evaluation milestone for malaria global health policy. The maps presented here contribute to a rational basis for control and

  15. A new world malaria map: Plasmodium falciparum endemicity in 2010

    Directory of Open Access Journals (Sweden)

    Gething Peter W

    2011-12-01

    Full Text Available Abstract Background Transmission intensity affects almost all aspects of malaria epidemiology and the impact of malaria on human populations. Maps of transmission intensity are necessary to identify populations at different levels of risk and to evaluate objectively options for disease control. To remain relevant operationally, such maps must be updated frequently. Following the first global effort to map Plasmodium falciparum malaria endemicity in 2007, this paper describes the generation of a new world map for the year 2010. This analysis is extended to provide the first global estimates of two other metrics of transmission intensity for P. falciparum that underpin contemporary questions in malaria control: the entomological inoculation rate (PfEIR and the basic reproductive number (PfR. Methods Annual parasite incidence data for 13,449 administrative units in 43 endemic countries were sourced to define the spatial limits of P. falciparum transmission in 2010 and 22,212 P. falciparum parasite rate (PfPR surveys were used in a model-based geostatistical (MBG prediction to create a continuous contemporary surface of malaria endemicity within these limits. A suite of transmission models were developed that link PfPR to PfEIR and PfR and these were fitted to field data. These models were combined with the PfPR map to create new global predictions of PfEIR and PfR. All output maps included measured uncertainty. Results An estimated 1.13 and 1.44 billion people worldwide were at risk of unstable and stable P. falciparum malaria, respectively. The majority of the endemic world was predicted with a median PfEIR of less than one and a median PfRc of less than two. Values of either metric exceeding 10 were almost exclusive to Africa. The uncertainty described in both PfEIR and PfR was substantial in regions of intense transmission. Conclusions The year 2010 has a particular significance as an evaluation milestone for malaria global health policy. The

  16. Brucella epididymo-orchitis: a consideration in endemic area

    Directory of Open Access Journals (Sweden)

    Jaffar A. Al-Tawfiq

    2006-06-01

    Full Text Available Brucellosis is a zoonotic disease caused by Brucella sp. and may affect many parts of the body. Brucella epididymo-orchitis had been reported in up to 20% of patients with brucellosis. This is a case report of Brucella epididymo-orchitis in a Saudi male patient. He presented with a unilateral swelling of the left testicle. He had fever, arthralgia and night sweats. Ultrasound examination revealed enlarged left epididymis and testicle. Brucella serology was positive and the patient responded to treatment with doxycycline and gentamicin. Thus, brucella infection should be considered in the differential diagnosis of patients presenting with epididymo-orchitis from an endemic area.

  17. Old-field plant succession on the Pajarito Plateau

    International Nuclear Information System (INIS)

    Foxx, T.; Mullen, M.; Salisbury, M.; Tierney, G.

    1997-10-01

    Eight fallow historic fields of the ponderosa pine and pinon-juniper cover types were surveyed to determine species composition and distribution. The purpose of the study was to understand plant succession on old fields as related to mechanically manipulated sites such as material disposal areas (MDAs). Additionally, the authors wanted a listing of species on disturbed lands of the Pajarito Plateau to aide in the reclamation planning of MDAs using native species. They also wanted to determine if any species could be used as an indicator of disturbance. The eight historic fields were all within Los Alamos County, New Mexico, and had been abandoned in 1943. Two sites were within the boundaries of Los Alamos National Laboratory and were studied both in 1982 and 1993. The study provides a description of each of the field sites, historic information about the homesteads from patent applications, a photographic record of some of the sites, and a listing of species found within each field. The study showed that there were 78 different plant species found on disturbed sites. Of these 78 species, 23 were found to be dominant on one or more of the MDAs or old fields. Although, the disturbance history of each site is imperfectly known, the study does provide an indication of successional processes within disturbed sites of the Pajarito Plateau. Additionally, it provides a listing of species that will invade disturbed sites, species that may be used in site reclamation

  18. Uranium exploration of the Colorado Plateau: interim staff report

    International Nuclear Information System (INIS)

    1980-10-01

    This report is an issue of the original draft copy of the Interim Staff Report on Uranium Exploration on the Colorado Plateau, dated June 1951. The original draft copy was only recently located and is being published at this time because of the interest in the contained historical content. The table of contents of this report lists: history of uranium mining; geology; proposed program for the geologic investigations section; general activities of industry and government; and future exploration of sedimentary uranium deposits and anticipated results. Under the proposed program section are: future of the copper-uranium deposits as a source of uranium; uraniferous asphaltite deposits; and commission exploration and future possibilities. The section on general activities of industry and government includes: exploratory and development drilling; field investigations and mapping; early geologic investigations and investigations by the US geological survey; and geophysical exploration. Tables are also presented on: uranium production by districts; US Geological survey drilling statistics; Colorado Exploration Branch drilling statistics; summary of drilling projects; and comparative yearly core-drill statistics on the Colorado Plateau

  19. Unilatelaral iris plateau syndrome after the use of ecstasy

    Directory of Open Access Journals (Sweden)

    Jovanović Predrag

    2009-01-01

    Full Text Available Bacground. Courmon street name for 3,4-Methylenedioxymethamphetamine (MDMA is ecstasy. This widely abused 'recreational' drug causes both an increased release of monoamine neurotransmitters, including serotonine and dopamine, and an increased reuptake inhibition of serotonin. As a consequence, mydriasis and increased intraocular pressure (IOP in predisposed patients occur. We present herein a rare case of acute increased IOP after use of ecstasy. Case report. A female patient, aged 38 years, visited doctor complaing of a decreased vision acuity and severe pain in the left eye and in the left part of the head. The initial treatment was urgent antiglaucomatous therapy followed by withdrawal of subjective problems of the patient and improvement of objective finding. History taking procedure reveled that just before the onset of the pain the patient had used ecstasy and had had similar 'experience' 6 years ago after cocaine snorting. She had not been to a doctor although she had experienced sporadic migrenous pain. Previous medical records excavation of revealed optic disk (cup-to-dise C/D=06, Bjerum arcuate scotoma and iris plateau with narrow chamber angle (Scheie II- III so the diagnosis was a rare unilateral iris plateau syndrome of the left eye. Although the patient was given some pieces of information about the dangerous and possible deadly consequences of psychoactive substance abuse, she has not continue the treatment. Conclusion. Ecstasy abuse might cause a complete loss of vision, thus medicametous and surgical treatment are obligatory.

  20. Aerosol vertical distribution characteristics over the Tibetan Plateau

    International Nuclear Information System (INIS)

    Deng, Z Q; Han, Y X; Zhao, Q; Li, J

    2014-01-01

    The Stratospheric Aerosol and Gas Experiment II (SAGE II) aerosol products are widely used in climatic characteristic studies and stratospheric aerosol pattern research. Some SAGE II products, e.g., temperature, aerosol surface area density, 1020 nm aerosol extinction coefficient and dust storm frequency, from ground-based observations were analysed from 1984 to 2005. This analysis explored the time and spatial variations of tropospheric and stratospheric aerosols on the Tibet Plateau. The stratospheric aerosol extinction coefficient increased more than two orders of magnitude because of a large volcanic eruption. However, the tropospheric aerosol extinction coefficient decreased over the same period. Removing the volcanic eruption effect, the correlation coefficient for stratospheric AOD (Aerosol Optical Depth) and tropospheric AOD was 0.197. Moreover, the correlation coefficient for stratospheric AOD and dust storm frequency was 0.315. The maximum stratospheric AOD was attained in January, the same month as the tropospheric AOD, when the Qaidam Basin was the centre of low tropospheric AOD and the large mountains coincided with high stratospheric AOD. The vertical structure generated by westerly jet adjustment and the high altitude of the underlying surface of the Tibetan Plateau were important factors affecting winter stratospheric aerosols

  1. Multielement stoichiometry of submerged macrophytes across Yunnan plateau lakes (China).

    Science.gov (United States)

    Xing, Wei; Wu, Haoping; Shi, Qiao; Hao, Beibei; Liu, Han; Wang, Zhixiu; Liu, Guihua

    2015-05-13

    Stoichiometric homeostasis of element composition is one of the central concepts of ecological stoichiometry. We analyzed concentrations of macroelements (C, N, P, Ca, K, Mg, S), microelements (Cu, Fe, Mn, Mo, Ni, Zn) and beneficial elements (Na, Se, Si) in submerged macrophytes, water and sediments across 20 Yunnan plateau lakes. We predicted that tissue element composition in submerged macrophytes is affected by lake trophic level and taxonomy, and submerged macrophytes have weak stoichiometric homeostasis for all above 16 elements. Canonical discriminant analyses successfully discriminated among trophic level groups and taxa groups. Of all the elements, C, N, P and S most effectively discriminated among trophic level groups across 20 lakes, revealing lake trophic level mostly affect tissue macroelement composition in submerged macrophytes; while Ca, K and Se most effectively discriminated among submerged macrophytes taxa groups, suggesting taxonomy mostly affect compositions of macroelements and beneficial elements in submerged macrophytes. In addition, the stoichiometric homeostatic coefficient of 1/HCa:C for all five taxa of submerged macrophytes were less than zero, suggesting submerged macrophytes in Yunnan plateau lakes have strong Ca stoichiometric homeostasis. Our findings, not only broaden the knowledge of multielement stoichiometric homeostasis, but also help to choose most appropriate lake management strategy.

  2. Snow surface microbiome on the High Antarctic Plateau (DOME C).

    Science.gov (United States)

    Michaud, Luigi; Lo Giudice, Angelina; Mysara, Mohamed; Monsieurs, Pieter; Raffa, Carmela; Leys, Natalie; Amalfitano, Stefano; Van Houdt, Rob

    2014-01-01

    The cryosphere is an integral part of the global climate system and one of the major habitable ecosystems of Earth's biosphere. These permanently frozen environments harbor diverse, viable and metabolically active microbial populations that represent almost all the major phylogenetic groups. In this study, we investigated the microbial diversity in the surface snow surrounding the Concordia Research Station on the High Antarctic Plateau through a polyphasic approach, including direct prokaryotic quantification by flow cytometry and catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH), and phylogenetic identification by 16S RNA gene clone library sequencing and 454 16S amplicon pyrosequencing. Although the microbial abundance was low (<10(3) cells/ml of snowmelt), concordant results were obtained with the different techniques. The microbial community was mainly composed of members of the Alpha-proteobacteria class (e.g. Kiloniellaceae and Rhodobacteraceae), which is one of the most well-represented bacterial groups in marine habitats, Bacteroidetes (e.g. Cryomorphaceae and Flavobacteriaceae) and Cyanobacteria. Based on our results, polar microorganisms could not only be considered as deposited airborne particles, but as an active component of the snowpack ecology of the High Antarctic Plateau.

  3. Snow surface microbiome on the High Antarctic Plateau (DOME C.

    Directory of Open Access Journals (Sweden)

    Luigi Michaud

    Full Text Available The cryosphere is an integral part of the global climate system and one of the major habitable ecosystems of Earth's biosphere. These permanently frozen environments harbor diverse, viable and metabolically active microbial populations that represent almost all the major phylogenetic groups. In this study, we investigated the microbial diversity in the surface snow surrounding the Concordia Research Station on the High Antarctic Plateau through a polyphasic approach, including direct prokaryotic quantification by flow cytometry and catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH, and phylogenetic identification by 16S RNA gene clone library sequencing and 454 16S amplicon pyrosequencing. Although the microbial abundance was low (<10(3 cells/ml of snowmelt, concordant results were obtained with the different techniques. The microbial community was mainly composed of members of the Alpha-proteobacteria class (e.g. Kiloniellaceae and Rhodobacteraceae, which is one of the most well-represented bacterial groups in marine habitats, Bacteroidetes (e.g. Cryomorphaceae and Flavobacteriaceae and Cyanobacteria. Based on our results, polar microorganisms could not only be considered as deposited airborne particles, but as an active component of the snowpack ecology of the High Antarctic Plateau.

  4. Deformation of the southeast part of the Columbia Plateau

    International Nuclear Information System (INIS)

    Hooper, P.R.; Camp, V.E.

    1981-01-01

    Four structural elements north of the Olympic-Wallowa lineament in the southeast part of the Columbia Plateau (Washington, Idaho, and Oregon) are (1) the offlap of progressively younger basalt units from prebasalt topographic highs; (2) east-west open folds associated with reverse faulting; (3) northwest-southeast, northeast-southwest, and north-south faults with predominantly vertical displacement; and (4) vertical north-northwest-south-southeast feeder dikes. These may be explained by (1) a regional east to west tilting of the plateau caused by the isostatic rise of older rocks on the eastern margin; (2) a stress regime with a horizontal maximum principal stress in a north-northwest-south-southeast direction, and a horizontal minimum principal stress in a west-southwest-east-northeast direction; and (3) reactivation of an older northwest-southeast, northeast-southwest, and north-south structural grain in the pre-Miocene basement. The stress regime is similar to that envisaged for the area southwest of the Olympic-Wallowa lineament, and the difference in the type of deformation on either side of that feature may be attributed to differences in the thickness of the crust across the ancient boundary

  5. Surface hydrologic investigations of the Columbia Plateau Region, Washington

    International Nuclear Information System (INIS)

    Leonhart, L.S.

    1979-07-01

    The Washington State portion of the Columbia Plateau is divided into six hydrologic sub-basins on the basis of the principal surface drainage systems present, structural and topographic relationships, and political and other considerations. Baseline descriptions of the surface water systems and resources are presented for the Columbia Plateau with emphasis on the Pasco Sub-basin. A preliminary evaluation of the hydrologic budget for each sub-basin is derived. For each sub-basin, recharge/discharge relationships arising from precipitation/evapotranspiration/runoff, stream losses and gains, and artificial mechanisms are determined on the basis of available data. The net exchange between surface and groundwater systems is evaluated and relative estimates of the net groundwater flow into or out of the sub-basin are obtained. An evaluation is made of hydrologic risk factors arising from: (1) tributary flooding in eastern Washington; and, (2) major flooding of the Columbia River within the Pasco Sub-basin. Scenarios are presented for credible natural and man-generated catastrophic events

  6. Old-field plant succession on the Pajarito Plateau

    Energy Technology Data Exchange (ETDEWEB)

    Foxx, T.; Mullen, M.; Salisbury, M. [Los Alamos National Lab., NM (United States); Tierney, G. [Tierney (Gail), Santa Fe, NM (United States)

    1997-10-01

    Eight fallow historic fields of the ponderosa pine and pinon-juniper cover types were surveyed to determine species composition and distribution. The purpose of the study was to understand plant succession on old fields as related to mechanically manipulated sites such as material disposal areas (MDAs). Additionally, the authors wanted a listing of species on disturbed lands of the Pajarito Plateau to aide in the reclamation planning of MDAs using native species. They also wanted to determine if any species could be used as an indicator of disturbance. The eight historic fields were all within Los Alamos County, New Mexico, and had been abandoned in 1943. Two sites were within the boundaries of Los Alamos National Laboratory and were studied both in 1982 and 1993. The study provides a description of each of the field sites, historic information about the homesteads from patent applications, a photographic record of some of the sites, and a listing of species found within each field. The study showed that there were 78 different plant species found on disturbed sites. Of these 78 species, 23 were found to be dominant on one or more of the MDAs or old fields. Although, the disturbance history of each site is imperfectly known, the study does provide an indication of successional processes within disturbed sites of the Pajarito Plateau. Additionally, it provides a listing of species that will invade disturbed sites, species that may be used in site reclamation.

  7. [Tibial plateau fractures in winter sports. Current treatment options].

    Science.gov (United States)

    Zimmermann, V

    2014-01-01

    Tibial plateau fractures overall and especially in winter sports are rare. However, the incidence in recent years is increasing. In a retrospective study from 2009-2012, we found 52 injuries affiliated with winter sports. Noticeable was the high rate of severe injury patterns. In 20 of the 52 cases, there were complete articular or bicondylar fractures (38 %). In 25 cases (48 %), fragment dislocation corresponding to the Moore classification was observed. The operative algorithm was based on the initial soft tissue damage and the type of fracture. A two or more stage procedure with first line soft tissue management and temporary external fixation stabilization was performed 12 times. The final internal osteosynthesis was based on the morphology of the fracture, i.e., direct exposition and stabilization of relevant fracture patterns. In 24 cases (46 %), there was a need for two (or more) approaches. In the anterior aspect of the tibial head, customary implants were used; posterior pathologies were stabilized with low-dimension implants. Summarizing with regard to the literature, there is a more discriminating view of tibial plateau fractures, regarding all relevant fracture patterns. Thus, different options in operative access and choice of implants can be made.

  8. Surface hydrologic investigations of the Columbia Plateau region, Washington

    International Nuclear Information System (INIS)

    Leonhart, L.S.

    1979-01-01

    The Washington State portion of the Columbia Plateau is divided into six hydrologic sub-basins on the basis of the principal surface drainage systems present, structural and topographic relationships, and political and other considerations. Baseline descriptions of the surface water systems and resources are presented for the Columbia Plateau with emphasis on the Pasco Sub-basin. A preliminary evaluation of the hydrologic budget for each sub-basin is derived. For each sub-basin, recharge/discharge relationships arising from precipitation/evapotranspiration/runoff, stream losses and gains, and artificial mechanisms are determined on the basis of available data. The net exchange between surface and ground-water systems is evaluated and relative estimates of the net ground-water flow into or out of the sub-basin are obtained. An evaluation is made of hydrologic risk factors arising from: (1) tributary flooding in eastern Washington; and (2) major flooding of the Columbia River within the Pasco Sub-basin. Scenarios are presented for credible natural and man-generated catastrophic events

  9. Climatic variability of the column ozone over the Iranian plateau

    Science.gov (United States)

    Mousavi, Seyyed Shafi; Farajzadeh, Manuchehr; Rahimi, Yousef Ghavidel; Bidokhti, Abbasali Aliakbari

    2017-06-01

    This study analyzes the total ozone column (TOC) variability over the Iranian plateau (Esfahan) from 1978 to 2011. Results show that the annual average of TOC in Esfahan tends to decrease with time, which is strongly dependent on the season, with maximum values during the winter-spring months (more than 2.2 %/decade). By applying a defined threshold that includes the TOC monthly -2 σ, it is found that the maximum occurrence of low ozone events (LOEs) tends to be more frequent in the second half of year with about four-fifth of the observed LOEs (last summer, autumn, and early winter). During two cases of LOE, the tropopause height (TH) was uplifted 2-4 km with temperature of 10 °C colder than the long-term mean, and the synoptic pattern was characterized by high-pressure systems in UTLS region. The extreme LOEs were consistent with the horizontal transport of ozone-poor air toward the Iranian plateau and vertical advection in UTLS region. The former mechanism plays a primary role in formation of extreme LOEs based on the observed TOC reductions during previous days over the source regions (Sahara desert and Himalaya region). Day-to-day variations of maximum UV index during LOEs show that by a decrease in TOC 14 %, while the aerosol optical depth (AOD) in the cloudless condition reach their lowest rates (lower than 0.3), UV radiation exceeds very high and extreme levels in late winter and mid-spring, respectively.

  10. Crop characteristics and their temporal change on the Loess Plateau of China

    NARCIS (Netherlands)

    Wu Yongqiu,; Xie Kunqing,; Zhang Qingchun,; Zhnag Yan,; Xie Yun,; Zhang Guanghui,; Zhang Wenbo,; Ritsema, C.J.

    2003-01-01

    Crop characteristics with obvious seasonal changes strongly influence soil loss. The purpose of this study is to measure and analyze the plant characteristics and their seasonal change in the Loess Plateau. A small watershed, Danangou in the Loess Plateau of north China, was selected for this study.

  11. Mapping the plateau of novices in virtual reality simulation training of mastoidectomy

    DEFF Research Database (Denmark)

    A.W. Andersen, Steven; Konge, Lars; Mikkelsen, Peter Trier

    2016-01-01

    To explore why novices' performance plateau in directed, self-regulated virtual reality (VR) simulation training and how performance can be improved.......To explore why novices' performance plateau in directed, self-regulated virtual reality (VR) simulation training and how performance can be improved....

  12. Control of Eospalax baileyi (Plateau Zokor) with arrow traps in western China

    NARCIS (Netherlands)

    Kong, Yang; Xidong, Li; Gaowei, Xu; Wei, Liu; Meerburg, B.G.

    2016-01-01

    In order to manage Eospalax (Myospalax) baileyi (Plateau zokors) pests with physical method, the efficacy of four different arrow traps was tested to control the plateau zokor in Sichuan Northwest Prairie, China. Population densities of 39.7-42.1 ha-1 were found in the test plots. Such densities

  13. Exoemission of Ethiopian soils and the endemicity of non-filarial elephantiasis

    Energy Technology Data Exchange (ETDEWEB)

    Davies, J.E. (Birmingham Univ. (UK). Dept. of Anatomy); Townsend, P.D. (Sussex Univ., Brighton (UK))

    1983-01-01

    Non-filarial elephantiasis is an endemic disease in the bare-footed population of Ethiopia. The distribution of this condition is linked with that of local red clay soil. Recently, thermoluminescence has been successfully used to distinguish between endemic and non-endemic soils. Instrinsic lattice defects, frozen in during cooling of volcanic material, are considered to be responsible for characteristic thermoluminescence signals. However, the biological reactivity of the absorbed soil particles will depend upon their surface properties. Exoemission has therefore been studied in samples from both endemic (5 samples) and non-endemic (4 samples) areas. All samples from endemic areas, on first heating, demonstrate an emission peak at 75/sup 0/C. Post-irradiation storage of samples in a moist atmosphere tends to decrease emissivity while wetting irreversibly reduces the response to irradiation. In an hydrated biological environment, this surface reactivity may be linked to the pathogenicity of the soil particles.

  14. Exoemission of Ethiopian soils and the endemicity of non-filarial elephantiasis

    International Nuclear Information System (INIS)

    Davies, J.E.

    1983-01-01

    Non-filarial elephantiasis is an endemic disease in the bare-footed population of Ethiopia. The distribution of this condition is linked with that of local red clay soil. Recently, thermoluminescence has been successfully used to distinguish between endemic and non-endemic soils. Instrinsic lattice defects, frozen in during cooling of volcanic material, are considered to be responsible for characteristic thermoluminescence signals. However, the biological reactivity of the absorbed soil particles will depend upon their surface properties. Exoemission has therefore been studied in samples from both endemic (5 samples) and non-endemic (4 samples) areas. All samples from endemic areas, on first heating, demonstrate an emission peak at 75 0 C. Post-irradiation storage of samples in a moist atmosphere tends to decrease emissivity while wetting irreversibly reduces the response to irradiation. In an hydrated biological environement, this surface reactivity may be linked to the pathogenicity of the soil particles. (author)

  15. Long-term complications following tibial plateau levelling osteotomy in small dogs with tibial plateau angles > 30°.

    Science.gov (United States)

    Knight, Rebekah; Danielski, Alan

    2018-04-21

    Tibial plateau levelling osteotomy (TPLO) is commonly performed for surgical management of cranial cruciate ligament (CCL) disease. It has been suggested that small dogs may have steeper tibial plateau angles (TPAs) than large dogs, which has been associated with increased complication rates after TPLO. A retrospective study was performed to assess the rate and nature of long-term complications following TPLO in small dogs with TPAs>30°. Medical records were reviewed for dogs with TPAs>30° treated for CCL rupture by TPLO with a 2.0 mm plate over a five-year period. Radiographs were assessed to determine TPA, postoperative tibial tuberosity width and to identify any complication. Up-to-date medical records were obtained from the referring veterinary surgeon and any complications in the year after surgery were recorded. The effects of different variables on complication rate were assessed using logistic regression analysis. Minor complications were reported in 22.7 per cent of cases. This is similar to or lower than previously reported complication rates for osteotomy techniques in small dogs and dogs with steep TPAs. A smaller postoperative TPA was the only variable significantly associated with an increased complication rate. No major complications were identified. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Global warming and extinctions of endemic species from biodiversity hotspots.

    Science.gov (United States)

    Malcolm, Jay R; Liu, Canran; Neilson, Ronald P; Hansen, Lara; Hannah, Lee

    2006-04-01

    Global warming is a key threat to biodiversity, but few researchers have assessed the magnitude of this threat at the global scale. We used major vegetation types (biomes) as proxies for natural habitats and, based on projected future biome distributions under doubled-CO2 climates, calculated changes in habitat areas and associated extinctions of endemic plant and vertebrate species in biodiversity hotspots. Because of numerous uncertainties in this approach, we undertook a sensitivity analysis of multiple factors that included (1) two global vegetation models, (2) different numbers of biome classes in our biome classification schemes, (3) different assumptions about whether species distributions were biome specific or not, and (4) different migration capabilities. Extinctions were calculated using both species-area and endemic-area relationships. In addition, average required migration rates were calculated for each hotspot assuming a doubled-CO2 climate in 100 years. Projected percent extinctions ranged from hotspots were the Cape Floristic Region, Caribbean, Indo-Burma, Mediterranean Basin, Southwest Australia, and Tropical Andes, where plant extinctions per hotspot sometimes exceeded 2000 species. Under the assumption that projected habitat changes were attained in 100 years, estimated global-warming-induced rates of species extinctions in tropical hotspots in some cases exceeded those due to deforestation, supporting suggestions that global warming is one of the most serious threats to the planet's biodiversity.

  17. Fasciolopsiasis: Endemic focus of a neglected parasitic disease in Bihar

    Directory of Open Access Journals (Sweden)

    A Achra

    2015-01-01

    Full Text Available Purpose: To describe a newly discovered, previously unreported endemic focus of fasciolopsiasis in the Phulwaria village, under tehsil Sugauli, East Champaran, Bihar. Materials and Methods: A study was conducted at village Phulwaria, following diagnosis of fasciolopsiasis in three children from the village. A total of 120 individuals, including all the children and adults who gave history of recent passage of red fleshy masses in their stool, were included in the study. The cases of fasciolopsiasis were treated with Praziquantel 25 mg/kg, three doses a day. Risk factors for the transmission of the parasite in the village were also studied. Results: Questionnaire revealed majority of the population suffering from abdominal discomfort and passage of red fleshy masses in stool. These fleshy masses were identified as Fasciolopsis buski. One hundred and eighteen individuals were presumably considered as cases of the parasitic infection. After treatment with Praziquantel, all of them passed the parasite in their stool for the next 2-3 days. On investigating, it was observed that all the conditions required for effective continuation of the life cycle of the parasite were present in this village. Conclusion: This study draws attention to a new endemic focus of fasciolopsiasis in Bihar, with a very high prevalence due to poverty, the lack of awareness about the parasite in villagers as well as ignorance among local medical practitioners. There is an urgent need for mass campaign around the region for its effective control.

  18. Enhancing the early differential diagnosis of plateau iris and pupillary block using a-scan ultrasonography.

    Directory of Open Access Journals (Sweden)

    Yu-Yen Chen

    Full Text Available To distinguish the frequently misdiagnosed plateau iris eyes from pupillary block group and normal group, we compared the ocular biometrical parameters of them by A-scan ultrasongraphy.In total, we retrospectively reviewed general characteristics and ocular findings including ocular biometric measurements of 71 normal, 39 plateau iris, and 83 pupillary block eyes.The normal controls, plateau iris group and pupillary block group were significantly different in age, but not in gender. The anterior chamber depth tended to decrease and the lens thickness tended to increase from normal to plateau iris to pupillary block eyes. Compared to those of plateau iris group, the pupillary block group had significantly shallower anterior chamber depth (2.90mm vs. 2.33mm; p<0.001, thicker lens (4.77mm vs. 5.11mm; p<0.001, shorter axial length (23.16mm vs. 22.63mm; p<0.001, smaller relative lens position (2.28 vs. 2.16; p<0.001 and larger lens/axial length factor (2.06 vs. 2.26; p<0.001. However, when comparing plateau iris and normal eyes, only axial length and lens/axial length factor were significantly different (23.16 vs. 23.54; p<0.05 and 2.06 vs. 1.96; p<0.05.Measured by A-scan ultrasonography, the ocular biometrics of plateau iris were significantly different from those of pupillary block eyes. However, our A-scan ultrasongraphy generally found no significant biometric differences between plateau iris and normal eyes. These findings suggest that while A-scan ultrasonography might be used as a practical tool for differentiating plateau iris and papillary block eyes, a more meticulous gonioscopy and other assessments may be necessary to distinguish plateau iris from normal eyes.

  19. Some heavy metals levels in drinking water and social characteristics in buruli ulcer endemic and non-endemic communities in the Amansie West district

    International Nuclear Information System (INIS)

    Odeh-Agbozo, Francis

    2009-06-01

    Buruli ulcer (BU) is a skin disease caused by mycobacterium ulcerans(MU). It is often associated with slow flowing or stagnant water and increase in the incidence of disease is also associated with the ecological transformation. Several risk factors have been identified and a number of transmission mechanisms suggested. However, the exact mechanism of transmission and development of Buruli ulcer through water related human activities are unknown. A study was carried out to compare concentrations of cadmium, lead and aluminium in drinking water samples and some social characteristics from endemic and non-endemic communities in the Amansie- West District of Ghana. Ninety-six drinking water sources were sampled from boreholes and hand-dug wells in the study area. The analysis of the samples showed that the average concentration of cadmium was significantly higher (p ≤ 0.05) in endemic communities than in non-endemic communities even though all the values were below the WHO guideline values of 0.003mg/L. The average concentration of Lead and Aluminium were lower in endemic communities than in non-endemic communities, but the differences between the average concentrations were not statistically significant ( p≥ 0.95 for Lead, p≥ 0.30 for Aluminium). Aluminium concentrations in all the samples were however lower than the WHO recommended guideline value of 0.1mg/L, whilst the concentration of lead was higher than the recommended guideline value of several communities. It was therefore concluded that Cadmium, Lead and Aluminium may not contribute to the occurrence and transmission of BU. In relation to the social characteristics, the educational level was generally poorer in endemic areas than in the non-endemic areas. The endemic communities used poorer source of water which include streams and hand-dug wells, unlike non-endemic communities which had better sources of water- boreholes and pipe-borne water only. Field observation showed that people in the endemic

  20. Comparative study of fluoride concentration in human serum and drinking water in fluorinated endemic and non endemic areas of pakistan

    International Nuclear Information System (INIS)

    Qayyum, M.; Ahmad, B.; Ahmad, M.

    2013-01-01

    For comparing the human blood serum and drinking water fluoride levels of subjects with dental fluorosis and bony deformities, this study is carried out with individuals ranging 8-17 age group fluorinated Sham Ki Bhatiyan, Punjab (endemic) and Queens Road, Lahore, Punjab (non-endemic) areas. Fluoride concentrations were determined using ion selective electrode methodology and statistically compared. Both the groups showed a significant difference (p < 0.05). Subjects from fluorotic area showed high concentration of fluoride in water and blood serum samples (mean value: 135.587+-77.435 and 2.765+-0.469 micro molL/sup -1/ in water and blood serum samples respectively) as compared to controls (mean value: 19.509+-2.432 and 2.364+- 0.667 micro molL -1). These findings indicate that serum and water fluoride concentrations have a significant positive dose response relationship with the prevalence of dental fluorosis in an area associated with high fluoride level in drinking water. (author)

  1. The shape of soap films and Plateau borders

    International Nuclear Information System (INIS)

    Fortes, M A; Teixeira, P I C; Deus, A M

    2007-01-01

    We have calculated the shapes of flat liquid films, and of the transition region to the associated Plateau borders (PBs), by integrating the Laplace equation with a position-dependent surface tension γ(x), where 2x is the local film thickness. We discuss films in either zero or non-zero gravity, using standard γ(x) potentials for the interaction between the two bounding surfaces. We have investigated the effects of the film flatness, liquid underpressure, and gravity on the shape of films and their PBs. Films may exhibit 'humps' and/or 'dips' associated with inflection points and minima of the film thickness. Finally, we propose an asymptotic analytical solution for the film width profile

  2. 200 Area plateau inactive miscellaneous underground storage tanks locations

    International Nuclear Information System (INIS)

    Brevick, C.H.

    1997-01-01

    Fluor Daniel Northwest (FDNW) has been tasked by Lockheed Martin Hanford Corporation (LMHC) to incorporate current location data for 64 of the 200-Area plateau inactive miscellaneous underground storage tanks (IMUST) into the centralized mapping computer database for the Hanford facilities. The IMUST coordinate locations and tank names for the tanks currently assigned to the Hanford Site contractors are listed in Appendix A. The IMUST are inactive tanks installed in underground vaults or buried directly in the ground within the 200-East and 200-West Areas of the Hanford Site. The tanks are categorized as tanks with a capacity of less than 190,000 liters (50,000 gal). Some of the IMUST have been stabilized, pumped dry, filled with grout, or may contain an inventory or radioactive and/or hazardous materials. The IMUST have been out of service for at least 12 years

  3. The shape of soap films and Plateau borders

    Energy Technology Data Exchange (ETDEWEB)

    Fortes, M A [Departamento de Engenharia de Materiais and Instituto de Ciencia e Engenharia de Materiais e SuperfIcies, Instituto Superior Tecnico, Avenida Rovisco Pais, P-1049-001 Lisbon (Portugal); Teixeira, P I C [Instituto Superior de Engenharia de Lisboa Rua Conselheiro EmIdio Navarro 1, P-1950-062 Lisbon (Portugal); Deus, A M [Departamento de Engenharia de Materiais and Instituto de Ciencia e Engenharia de Materiais e SuperfIcies, Instituto Superior Tecnico, Avenida Rovisco Pais, P-1049-001 Lisbon (Portugal)

    2007-06-20

    We have calculated the shapes of flat liquid films, and of the transition region to the associated Plateau borders (PBs), by integrating the Laplace equation with a position-dependent surface tension {gamma}(x), where 2x is the local film thickness. We discuss films in either zero or non-zero gravity, using standard {gamma}(x) potentials for the interaction between the two bounding surfaces. We have investigated the effects of the film flatness, liquid underpressure, and gravity on the shape of films and their PBs. Films may exhibit 'humps' and/or 'dips' associated with inflection points and minima of the film thickness. Finally, we propose an asymptotic analytical solution for the film width profile.

  4. Analysis of turbulence characteristics over the northern Tibetan Plateau area

    Science.gov (United States)

    Li, M. S.; Ma, Y. M.; Ma, W. Q.; Hu, Z. Y.; Ishikawa, H.; Su, Z. B.; Sun, G. L.

    2006-07-01

    Based on CATOP/Tibet [Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CA-IMP) on the Tibetan Plateau) turbulent data collected at the Bujiao (BJ) site of the Nagqu area, the turbulent structure and transportation characteristics in the near surface layer during summer are analyzed. The main results show that the relationship between the normalized standard deviation of 3D wind speed and stability satisfies the similarity law tinder both unstable and stable stratifications. The relations of normalized standard deviation of temperature and specific humidity to stability only obey the "-1/3 power law." tinder unstable conditions. In the case of stable stratifications, their relations to stability are dispersing. The sensible heat dominates in the dry period, while in the wet period, the latent heat is larger than the sensible heat.

  5. Plateau inflation from random non-minimal coupling

    International Nuclear Information System (INIS)

    Broy, Benedict J.; Roest, Diederik

    2016-06-01

    A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength ξ of the order N 2 e . In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of ξ, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes ξ≅10 4 obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observables measured.

  6. Regional basalt hydrology of the Columbia Plateau in Washington

    International Nuclear Information System (INIS)

    Tanaka, H.; Barrett, G.; Wildrick, L.

    1979-10-01

    This study is part of the Basalt Waste Isolation Project, operated for the US Department of Energy by Rockwell Hanford Operations. The overall purpose of the study is to assess locations within the Columbia River Basalt Group beneath the Hanford Site in south-central Washington suitable for a geologic repository for radioactive waste. This hydrologic study was made to describe the hydrologic characteristics of the basalt units of the Columbia Plateau. This was done by comprehensive data compilation, data interpretation and analysis. Data are presented in the form of maps and tables suitable as input information about the regional hydrology for possible future analysis by computer models. The report includes: an introduction; basic data; interpretation which covers stratigraphic trend surface, water levels, transmissivity and storage of aquifers, recharge, discharge, flow, subbasins, cross sections, references and appendix of record of wells

  7. Tibetan Plateau glacier and hydrological change under stratospheric aerosol injection

    Science.gov (United States)

    Ji, D.

    2017-12-01

    As an important inland freshwater resource, mountain glaciers are highly related to human life, they provide water for many large rivers and play a very important role in regional water cycles. The response of mountain glaciers to future climate change is a topic of concern especially to the many people who rely on glacier-fed rivers for purposes such as irrigation. Geoengineering by stratospheric aerosol injection is a method of offsetting the global temperature rise from greenhouse gases. How the geoengineering by stratospheric aerosol injection affects the mass balance of mountain glaciers and adjacent river discharge is little understood. In this study, we use regional climate model WRF and catchment-based river model CaMa-Flood to study the impacts of stratospheric aerosol injection to Tibetan Plateau glacier mass balance and adjacent river discharge. To facilitate mountain glacier mass balance study, we improve the description of mountain glacier in the land surface scheme of WRF. The improvements include: (1) a fine mesh nested in WRF horizontal grid to match the highly non-uniform spatial distribution of the mountain glaciers, (2) revising the radiation flux at the glacier surface considering the surrounding terrain. We use the projections of five Earth system models for CMIP5 rcp45 and GeoMIP G4 scenarios to drive the WRF and CaMa-Flood models. The G4 scenario, which uses stratospheric aerosols to reduce the incoming shortwave while applying the rcp4.5 greenhouse gas forcing, starts stratospheric sulfate aerosol injection at a rate of 5 Tg per year over the period 2020-2069. The ensemble projections suggest relatively slower glacier mass loss rates and reduced river discharge at Tibetan Plateau and adjacent regions under geoengineering scenario by stratospheric aerosol injection.

  8. The chromium in timberline forests in the eastern Tibetan Plateau.

    Science.gov (United States)

    Luo, Ji; Tang, Ronggui; She, Jia; Chen, Youchao; Gong, Yiwen; Zhou, Jun; Yu, Dong

    2013-10-01

    In order to study the regional distribution, trait and possible source of chromium in the eastern Tibetan Plateau, we collected samples of xylem, bark, leaves and twigs in two parallel northwest-southeast belt transects (TA and TB) from the Hengduan Mountains. According to the Cr mean concentration, organ/tissue was split into two groups: the high-level organ/tissue (twigs: 1.476 mg kg(-1)) and the low-level organ/tissue (bark: 0.413 mg kg(-1), leaves: 0.340 mg kg(-1) and xylem: 0.194 mg kg(-1)). The mean Cr concentrations of twigs and leaves in TB samples were higher than those in the TA samples, and the mean Cr concentration in both sites gradually reduced from southeast to northwest. Both the southeasterly and southwesterly monsoons could be significant, influential factors in this connection. The top three mean Cr concentrations were S7, S1 and S8, which were closer to the developed city. Mean Cr concentrations in S3, S4 and S5, (remote, high mountains) were relatively low. The high mountains acting as a barrier to the monsoon and the distance from the big city may play important roles in the distribution of Chromium. Furthermore, the relationship between the mean Cr concentration and precipitation, timberline trees as bio-monitors of chromium pollution in polluted areas and the possible source of Cr in the eastern Tibetan Plateau are also discussed. This study may provide reliable proof of Cr contamination processes, and so help in future to prevent further Cr pollution, and also be helpful in understanding the important function of forest ecosystems in relation to atmospheric pollution and global change. To better understand the characteristics of temporal and spatial distribution of Cr concentration, we found that tree ring, fine roots and soil samples are good choices.

  9. Pv rural electrification programme at the Bolivian high plateau

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo, E.; Aguilera, J. [Instituto de Energia Solar, ETSI Telecomunicacion, (Spain)

    1995-12-31

    Since 1988 the Institute of Solar Energy of the Universidad Politecnica de Madrid is carrying out a pv rural electrification programme at the Bolivian high plateau. This programme has been focused in three aspects: the domestic electrification, users participation and transfer technology. At present, there are about 1,500 electrified dwellings distributed in the Bolivian high plateau. We have got deep knowledge about life style and organization of the aymara Indians who are the inhabitants of the working zone. We think that this knowledge can be very useful for a large scale introduction of PV solar energy in this region. Finally, we present a new way to transfer PV technology to developing countries. Thanks to this programme a group of aymara Indians is able to manufacture charge regulators and electronic ballast to use in the PV installations of the programme. [Espanol] Desde 1988 el Instituto de Energia Solar de la Universidad Politecnica de Madrid esta llevando a cabo un programa fotovoltaico de electrificacion rural en la altiplanicie Boliviana. Este programa ha sido enfocado a tres aspectos: la electrificacion domestica, la participacion de los usuarios y la transferencia de la tecnologia. Actualmente, hay alrededor de 1500 conjuntos habitacionales electrificados distribuidos en la altiplanicie Boliviana. Hemos obtenido un profundo conocimiento del estilo de vida y de la organizacion de los indios aymara que son los habitantes de la zona de trabajo. Pensamos que este conocimiento puede ser muy util para una introduccion en gran escala de la energia solar fotovoltaica en esta region. Finalmente, presentamos una nueva forma de transferir la tecnologia fotovoltaica a paises en desarrollo. Gracias a este programa un grupo de indios aymara pueden fabricar reguladores de carga y balastros electronicos para ser usados en instalaciones fotovoltaicas del programa.

  10. Report on geologic remote sensing of the Columbia Plateau

    International Nuclear Information System (INIS)

    Sandness, G.A.; Kimball, C.S.; Schmierer, K.E.; Lindberg, J.W.

    1982-05-01

    The purpose of this remote sensing study is to identify faults or other geologic features which may have a significant bearing on the structural and tectonic character of the Hanford Site and the surrounding region. Landsat imagery, Skylab photographs, and U-2 photographs were analyzed to identify and map geologic photolineaments in the Columbia Plateau. The Landsat and Skylab imagery provided a regional perspective and allowed the identification of large-scale linear features. The U-2 photography provided much greater spatial resolution as well as a stereoscopic viewing capability. This allowed identification of smaller structural or geologic features and the identification of many cultural and nongeologic lineaments detected in the Landsat and Skylab imagery. The area studied totals, approximately 85,000 square miles, and encompasses virtually all exposures of Columbia River Basalt in the states of Washington, Oregon, and Idaho. It also includes an area bordering the Columbia River Basalt outcrop. This border area was studied in order to identify significant structures that may extend into the plateau. Included are a description of the procedures used for image analysis, 20 lineament maps at a scale of 1:250,000, geological summaries for the areas covered by the lineament maps, and discussions of many of the lineaments shown on the maps. Comparisons of the lineament maps with available geologic maps showed that the number of detected lineaments was much greater than the number of known faults and other linear features. Approximately 70% of the faults shown on the geologic maps were detected and are characterized as lineaments. Lineament trends in the northwest-southeast and northeast-southwest directions were found to predominate throughout the study area

  11. Evaporative cooling over the Tibetan Plateau induced by vegetation growth

    Science.gov (United States)

    Shen, Miaogen; Piao, Shilong; Jeong, Su-Jong; Zhou, Liming; Zeng, Zhenzhong; Ciais, Philippe; Chen, Deliang; Huang, Mengtian; Jin, Chun-Sil; Li, Laurent Z. X.; Li, Yue; Myneni, Ranga B.; Yang, Kun; Zhang, Gengxin; Zhang, Yangjian; Yao, Tandong

    2015-01-01

    In the Arctic, climate warming enhances vegetation activity by extending the length of the growing season and intensifying maximum rates of productivity. In turn, increased vegetation productivity reduces albedo, which causes a positive feedback on temperature. Over the Tibetan Plateau (TP), regional vegetation greening has also been observed in response to recent warming. Here, we show that in contrast to arctic regions, increased growing season vegetation activity over the TP may have attenuated surface warming. This negative feedback on growing season vegetation temperature is attributed to enhanced evapotranspiration (ET). The extra energy available at the surface, which results from lower albedo, is efficiently dissipated by evaporative cooling. The net effect is a decrease in daily maximum temperature and the diurnal temperature range, which is supported by statistical analyses of in situ observations and by decomposition of the surface energy budget. A daytime cooling effect from increased vegetation activity is also modeled from a set of regional weather research and forecasting (WRF) mesoscale model simulations, but with a magnitude smaller than observed, likely because the WRF model simulates a weaker ET enhancement. Our results suggest that actions to restore native grasslands in degraded areas, roughly one-third of the plateau, will both facilitate a sustainable ecological development in this region and have local climate cobenefits. More accurate simulations of the biophysical coupling between the land surface and the atmosphere are needed to help understand regional climate change over the TP, and possible larger scale feedbacks between climate in the TP and the Asian monsoon system. PMID:26170316

  12. Progenitors of low-luminosity Type II-Plateau supernovae

    Science.gov (United States)

    Lisakov, Sergey M.; Dessart, Luc; Hillier, D. John; Waldman, Roni; Livne, Eli

    2018-01-01

    The progenitors of low-luminosity Type II-Plateau supernovae (SNe II-P) are believed to be red supergiant (RSG) stars, but there is much disparity in the literature concerning their mass at core collapse and therefore on the main sequence. Here, we model the SN radiation arising from the low-energy explosion of RSG stars of 12, 25 and 27 M⊙ on the main sequence and formed through single star evolution. Despite the narrow range in ejecta kinetic energy (2.5-4.2 × 1050 erg) in our model set, the SN observables from our three models are significantly distinct, reflecting the differences in progenitor structure (e.g. surface radius, H-rich envelope mass and He-core mass). Our higher mass RSG stars give rise to Type II SNe that tend to have bluer colours at early times, a shorter photospheric phase, and a faster declining V-band light curve (LC) more typical of Type II-linear SNe, in conflict with the LC plateau observed for low-luminosity SNe II. The complete fallback of the CO core in the low-energy explosions of our high-mass RSG stars prevents the ejection of any 56Ni (nor any core O or Si), in contrast to low-luminosity SNe II-P, which eject at least 0.001 M⊙ of 56Ni. In contrast to observations, Type II SN models from higher mass RSGs tend to show an H α absorption that remains broad at late times (due to a larger velocity at the base of the H-rich envelope). In agreement with the analyses of pre-explosion photometry, we conclude that low-luminosity SNe II-P likely arise from low-mass rather than high-mass RSG stars.

  13. Relationship between gullying and landslides within the Barlad Plateau, Romania

    Science.gov (United States)

    Niacsu, Lilian; Ionita, Ion

    2016-04-01

    Located in the eastern Romania and extending on 8200 km2 the Barlad Plateau is considered the most typical subunit of the Moldavian Plateau. The sedimentary Miocene-Pliocene clay-sandy layers, inter-bedded with shallow sandstone and limestone are gently dipping toward S-SE as homoclinal structure. Land degradation through soil erosion, gullying and landslides represent the most important environmental threat in the region. By using both the classical research methods such as repeated field surveys and mapping, mathematical-statistical processing as well as the present-day methods based on the GIS software it was possible to precisely measure and evaluate the gully erosion rates and triggered landslides during the last two centuries, especially with a very high accuracy since 1960. Results have indicated that the landslide development is strongly controlled by gullying. Generally, by combining the areal growth of both gullying and new landslides within the selected study catchments, it is noticeable that 62 % of the total recent land degradation occurred during the last 55 years, with the remainder pre-1960. In addition, half of the gully areal growth occurred since 1961 but the new triggered landslides amount over three-quarters of the total area under landslides. This asymmetrical distribution reveals that usually a preparing time lag of tens of years is required for triggering landslides by gullying and this pattern depicts the common mechanism for landslide development. Acknowledgements: This work was partly supported by a grant from the Romanian National Authority for Scientific Research, CNDI-UEFISCDI, Project number PN-II-PT-PCCA-2011-3.2-0975.

  14. Pv rural electrification programme at the Bolivian high plateau

    Energy Technology Data Exchange (ETDEWEB)

    Lorenzo, E; Aguilera, J [Instituto de Energia Solar, ETSI Telecomunicacion, (Spain)

    1996-12-31

    Since 1988 the Institute of Solar Energy of the Universidad Politecnica de Madrid is carrying out a pv rural electrification programme at the Bolivian high plateau. This programme has been focused in three aspects: the domestic electrification, users participation and transfer technology. At present, there are about 1,500 electrified dwellings distributed in the Bolivian high plateau. We have got deep knowledge about life style and organization of the aymara Indians who are the inhabitants of the working zone. We think that this knowledge can be very useful for a large scale introduction of PV solar energy in this region. Finally, we present a new way to transfer PV technology to developing countries. Thanks to this programme a group of aymara Indians is able to manufacture charge regulators and electronic ballast to use in the PV installations of the programme. [Espanol] Desde 1988 el Instituto de Energia Solar de la Universidad Politecnica de Madrid esta llevando a cabo un programa fotovoltaico de electrificacion rural en la altiplanicie Boliviana. Este programa ha sido enfocado a tres aspectos: la electrificacion domestica, la participacion de los usuarios y la transferencia de la tecnologia. Actualmente, hay alrededor de 1500 conjuntos habitacionales electrificados distribuidos en la altiplanicie Boliviana. Hemos obtenido un profundo conocimiento del estilo de vida y de la organizacion de los indios aymara que son los habitantes de la zona de trabajo. Pensamos que este conocimiento puede ser muy util para una introduccion en gran escala de la energia solar fotovoltaica en esta region. Finalmente, presentamos una nueva forma de transferir la tecnologia fotovoltaica a paises en desarrollo. Gracias a este programa un grupo de indios aymara pueden fabricar reguladores de carga y balastros electronicos para ser usados en instalaciones fotovoltaicas del programa.

  15. Overcoming the Photovoltage Plateau in Large Bandgap Perovskite Photovoltaics.

    Science.gov (United States)

    Rajagopal, Adharsh; Stoddard, Ryan J; Jo, Sae Byeok; Hillhouse, Hugh W; Jen, Alex K-Y

    2018-05-09

    Development of large bandgap (1.80-1.85 eV E g ) perovskite is crucial for perovskite-perovskite tandem solar cells. However, the performance of 1.80-1.85 eV E g perovskite solar cells (PVKSCs) are significantly lagging their counterparts in the 1.60-1.75 eV E g range. This is because the photovoltage ( V oc ) does not proportionally increase with E g due to lower optoelectronic quality of conventional (MA,FA,Cs)Pb(I,Br) 3 and results in a photovoltage plateau ( V oc limited to 80% of the theoretical limit for ∼1.8 eV E g ). Here, we incorporate phenylethylammonium (PEA) in a mixed-halide perovskite composition to solve the inherent material-level challenges in 1.80-1.85 eV E g perovskites. The amount of PEA incorporation governs the topography and optoelectronic properties of resultant films. Detailed structural and spectroscopic characterization reveal the characteristic trends in crystalline size, orientation, and charge carrier recombination dynamics and rationalize the origin of improved material quality with higher luminescence. With careful interface optimization, the improved material characteristics were translated to devices and V oc values of 1.30-1.35 V were achieved, which correspond to 85-87% of the theoretical limit. Using an optimal amount of PEA incorporation to balance the increase in V oc and the decrease in charge collection, a highest power conversion efficiency of 12.2% was realized. Our results clearly overcome the photovoltage plateau in the 1.80-1.85 eV E g range and represent the highest V oc achieved for mixed-halide PVKSCs. This study provides widely translatable insights, an important breakthrough, and a promising platform for next-generation perovskite tandems.

  16. On the origin of endemic species in the Red Sea

    KAUST Repository

    DiBattista, Joseph

    2015-10-19

    Aim The geological and palaeo-climatic forces that produced the unique biodiversity in the Red Sea are a subject of vigorous debate. Here, we review evidence for and against the hypotheses that: (1) Red Sea fauna was extirpated during glacial cycles of the Pleistocene and (2) coral reef fauna found refuge within or just outside the Red Sea during low sea level stands when conditions were inhospitable. Location Red Sea and Western Indian Ocean. Methods We review the literature on palaeontological, geological, biological and genetic evidence that allow us to explore competing hypotheses on the origins and maintenance of shallow-water reef fauna in the Red Sea. Results Palaeontological (microfossil) evidence indicates that some areas of the central Red Sea were devoid of most plankton during low sea level stands due to hypersaline conditions caused by almost complete isolation from the Indian Ocean. However, two areas may have retained conditions adequate for survival: the Gulf of Aqaba and the southern Red Sea. In addition to isolation within the Red Sea, which separated the northern and southern faunas, a strong barrier may also operate in the region: the cold, nutrient-rich water upwelling at the boundary of the Gulf of Aden and the Arabian Sea. Biological data are either inconclusive or support these putative barriers and refugia, but no data set, that we know of rejects them. Genetic evidence suggests that many endemic lineages diverged from their Indian Ocean counterparts long before the most recent glaciations and/or are restricted to narrow areas, especially in the northern Red Sea. Main conclusions High endemism observed in the Red Sea and Gulf of Aden appears to have multiple origins. A cold, nutrient-rich water barrier separates the Gulf of Aden from the rest of the Arabian Sea, whereas a narrow strait separates the Red Sea from the Gulf of Aden, each providing potential isolating barriers. Additional barriers may arise from environmental gradients

  17. Vertebrate endemism in south-eastern Africa numerically redefines a biodiversity hotspot.

    Science.gov (United States)

    Perera, Sandun J; ProcheŞ, Şerban; Ratnayake-Perera, Dayani; Ramdhani, Syd

    2018-02-20

    We use numerical methods to explore patterns of vertebrate endemism in south-eastern Africa, refining the boundaries of the intuitively-defined Maputaland-Pondoland-Albany biodiversity hotspot, also proposing a zoogeographic regionalisation. An incidence matrix of 300 vertebrate species endemic to south-eastern Africa sensu lato in 37 operational geographic units were used in (a) phenetic cluster analysis (PCA) using the algorithm of unweighted pair-group method with arithmetic averages (phenetic approach), and (b) parsimony analysis of endemicity (PAE; parsimony approach), in order to numerically evaluate the bioregional delimitations. The analyses provide a valid biogeographical entity 37% larger than the Maputaland-Pondoland-Albany hotspot, but substantially (131%) higher in vertebrate endemicity viz. the Greater Maputaland-Pondoland-Albany (GMPA) region of vertebrate endemism. South-east Africa is recognised as a dominion in the global zoogeographical area hierarchy, with subordinate units including the GMPA province. Various spatially-based measures of endemism were mapped for vertebrate species restricted to the dominion, i.e. endemic to south-eastern Africa sensu stricto. Areas and centres of endemism detected respectively from PAE and PCA, within the south-east Africa dominion also support the refined boundary of the GMPA region of endemism, which provides a better spatial conservation priority compared to the Maputaland-Pondoland-Albany hotspot. Reptiles and amphibians are found to be the main drivers of the overall pattern of endemism, while the pattern in freshwater fish is the most distinctive. Our analyses also indicate a good congruence of the centres of endemism across different terrestrial vertebrate taxa.

  18. Cytological studies in Four Endemic Genera of Apiaceae from India

    Directory of Open Access Journals (Sweden)

    Kumar Vinod C. Gosavi

    2016-11-01

    Full Text Available The family Apiaceae comprises 428 genera worldwide, of which 68 are represented in India. Karnataka P.K. Mukh. & Constance, Pinda P.K. Mukh. & Constance, Polyzygus Dalzell, Sivadasania N. Mohanan & Pimenov and Vanasushava P.K. Mukh. & Constance are endemic genera to the country. The present communication is an attempt to provide chromosome counts and basic karyomorphology of Karnataka, Pinda, Polyzygus and Vanasushava. Somatic chromosome counts 2n = 22 and meiotic chromosome counts n = 11 are reported for the first time in Karnataka and Pinda while in Polyzygus 2n = 36 and in Vanasushava 2n = 44 are reported as new cytotypes in present investigation. Karyomophologically Pinda and Vanasushava showed affinities with Heracleum L. while Polyzygus showed advanced karyotype symmetry.

  19. Endemic malaria in four villages in Attapeu Province, Lao PDR.

    Science.gov (United States)

    Phetsouvanh, R; Vythilingam, I; Sivadong, B; Hakim, S Lokman; Chan, S T; Phompida, S

    2004-09-01

    A study was conducted in four villages in Attapeu Province, Lao PDR in 2002 to determine malaria endemicity. The study villages were Mixay, Beng Phoukham, Phou Vong and Pier Geo. Mass blood surveys were conducted in May, August, and October. Finger prick blood was collected for thick and thin blood film as well as for dipstick. The slide positivity rate was highest in Phou Hom in October (41.7%). Plasmodium falciparum was the dominant species comprising more than 80% of the cases. As a whole, the distribution of malaria was similar among males and females. Children below 15 years accounted for a large percentage of the cases. The sensitivity of the optimal dipstick was 62.36 and the specificity was 61.7. Microscopy was taken as the gold standard. Anopheles dirus was found to be the main vector and the vectorial capacity correlated well with the cases.

  20. Zika virus: Endemic and epidemic ranges of Aedes mosquito transmission

    Directory of Open Access Journals (Sweden)

    David F. Attaway

    2017-01-01

    Full Text Available Summary: As evidence linking Zika virus with serious health complications strengthens, public health officials and clinicians worldwide need to know which locations are likely to be at risk for autochthonous Zika infections. We created risk maps for epidemic and endemic Aedes-borne Zika virus infections globally using a predictive analysis method that draws on temperature, precipitation, elevation, land cover, and population density variables to identify locations suitable for mosquito activity seasonally or year-round. Aedes mosquitoes capable of transmitting Zika and other viruses are likely to live year-round across many tropical areas in the Americas, Africa, and Asia. Our map provides an enhanced global projection of where vector control initiatives may be most valuable for reducing the risk of Zika virus and other Aedes-borne infections. Keywords: Geographic information systems, Geographic information science, Risk mapping, Zika, Aedes modeling

  1. Zika virus: Endemic and epidemic ranges of Aedes mosquito transmission.

    Science.gov (United States)

    Attaway, David F; Waters, Nigel M; Geraghty, Estella M; Jacobsen, Kathryn H

    As evidence linking Zika virus with serious health complications strengthens, public health officials and clinicians worldwide need to know which locations are likely to be at risk for autochthonous Zika infections. We created risk maps for epidemic and endemic Aedes-borne Zika virus infections globally using a predictive analysis method that draws on temperature, precipitation, elevation, land cover, and population density variables to identify locations suitable for mosquito activity seasonally or year-round. Aedes mosquitoes capable of transmitting Zika and other viruses are likely to live year-round across many tropical areas in the Americas, Africa, and Asia. Our map provides an enhanced global projection of where vector control initiatives may be most valuable for reducing the risk of Zika virus and other Aedes-borne infections. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  2. Hepatobiliary fascioliasis in non-endemic zones: a surprise diagnosis.

    Science.gov (United States)

    Jha, Ashish Kumar; Goenka, Mahesh Kumar; Goenka, Usha; Chakrabarti, Amrita

    2013-03-01

    Fascioliasis is a zoonotic infection caused by Fasciola hepatica. Because of population migration and international food trade, human fascioliasis is being an increasingly recognised entity in nonendemic zones. In most parts of Asia, hepatobiliary fascioliasis is sporadic. Human hepatobiliary infection by this trematode has two distinct phases: an acute hepatic phase and a chronic biliary phase. Hepatobiliary infection is mostly associated with intense peripheral eosinophilia. In addition to classically defined hepatic phase and biliary phase fascioliasis, some cases may have an overlap of these two phases. Chronic liver abscess formation is a rare presentation. We describe a surprise case of hepatobiliary fascioliasis who presented to us with liver abscess without intense peripheral eosinophilia, a rare presentation of human fascioliasis especially in non-endemic zones. Copyright © 2013 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  3. Dynamic generalized linear models for monitoring endemic diseases

    DEFF Research Database (Denmark)

    Lopes Antunes, Ana Carolina; Jensen, Dan; Hisham Beshara Halasa, Tariq

    2016-01-01

    The objective was to use a Dynamic Generalized Linear Model (DGLM) based on abinomial distribution with a linear trend, for monitoring the PRRS (Porcine Reproductive and Respiratory Syndrome sero-prevalence in Danish swine herds. The DGLM was described and its performance for monitoring control...... and eradication programmes based on changes in PRRS sero-prevalence was explored. Results showed a declining trend in PRRS sero-prevalence between 2007 and 2014 suggesting that Danish herds are slowly eradicating PRRS. The simulation study demonstrated the flexibility of DGLMs in adapting to changes intrends...... in sero-prevalence. Based on this, it was possible to detect variations in the growth model component. This study is a proof-of-concept, demonstrating the use of DGLMs for monitoring endemic diseases. In addition, the principles stated might be useful in general research on monitoring and surveillance...

  4. Prevalence of hand osteoarthritis and knee osteoarthritis in Kashin-Beck disease endemic areas and non Kashin-Beck disease endemic areas: A status survey

    Science.gov (United States)

    Song, QuanQuan; Liu, Yun Qi; Sun, Li Yan; Deng, Qing; Wang, Shao Ping; Cao, Yan Hong; Zhang, Xue Ying; Jiang, Yuan Yuan; Lv, Hong Yan; Duan, Li Bin; Yu, Jun

    2018-01-01

    Osteoarthritis (OA) is a considerable health problem worldwide, and the prevalence of OA varies in different regions. In this study, the prevalence of OA in Kashin-Beck disease (KBD) and non-KBD endemic areas was examined, respectively. According to monitoring data, 4 types of regions (including none, mild, moderate and high KBD endemic areas) in Heilongjiang and Jilin provinces were selected. All local residents were eligible for inclusion criteria have undergone X-ray images of hands and anteroposterior image of knees. A total of 1673 cases were collected, 1446 cases were analyzed after removing the KBD patients (227). The overall hand OA and knee OA detection rates were 33.3% (481/1446) and 56.6% (818/1446), respectively. After being standardized by age, the detection rate of hand OA in the KBD endemic areas was significantly higher than that in the non-endemic endemic areas. Differently, there was no significant difference in the detection rates of knee OA between the KBD endemic areas and the non-endemic area. The correlation coefficient between the severity of OA and the severity of knee OA was 0.358 and 0.197 in the KBD and non-KBD endemic areas, respectively. Where the KBD historical prevalence level was higher, the severity of the residents’ hand OA was more serious. The detection rates of hand OA and knee OA increased with age. The detection rate of knee OA increased with the increase in body mass index. The prevalence of hand OA was closely related to the pathogenic factors of Kashin-Beck disease, and the prevalence of knee OA had no significant correlation with KBD pathogenic factors. PMID:29320581

  5. Etiology of Balkan endemic nephropathy: A multifactorial disease?

    International Nuclear Information System (INIS)

    Toncheva, Draga; Dimitrov, Tzvetan; Stojanova, Stiliana

    1998-01-01

    Balkan endemic nephropathy (BEN) is of great clinical importance in the restricted areas of Bulgaria, Rumania, Croatia, Serbia, Bosnia and Herzegovina. So far, studies on the etiological factors for BEN have not discovered any single environmental causative agent of this puzzling disease. These data reject the possibility of a purely environmental causation of BEN. The pattern of BEN transmission in the risk families is not typical for single gene disorders. Extensive epidemiological and genetic studies disclose characteristics of multifactorial (polygenic) inheritance of BEN. The evidences of 'familial tendency', variation of the risk for BEN depending on the number of sick parents and the degree of relatedness; the development of BEN in individuals from at-risk families who were born in non-endemic areas; the data that disease is not found in the gypsy population and the expressions of 3q25 cytogenetic marker suggest that the genetic factors play an important role as causative factors in BEN development. The possible impact of environmental triggers on individuals genetically predisposed to BEN could be supposed by the following data: the cytogenetic results of the increased frequency of folate sensitive Fra sites, spontaneous or radiation-induced aberrations in several bands in BEN patients, the data from the detailed analysis of breaks in BEN patients and controls that generate structural chromosome aberrations; the occurrence of BEN in immigrants. Genetical epidemiological approaches to etiology and prevention of BEN are proposed. The predisposing genes for BEN could be genes localized in a region between 3q25-3q26; transforming growth factor-β (TGF-β), genetic heterogeneity of xenobiotic-metabolizing enzymes; defects in the host's immune system. The predisposing genes for BEN patients with urinary tract tumors could be germline mutations in tumor suppressor genes and acquired somatic mutations in oncogenes

  6. [Factors contributing to endemic cholera in Douala, Cameroon].

    Science.gov (United States)

    Guévart, E; Noeske, J; Solle, J; Essomba, J M; Edjenguele, Mbonji; Bita, A; Mouangue, A; Manga, B

    2006-06-01

    Cholera has been endemic in Douala, Cameroon since 1971. A number of environmental factors favourize the survival of the Vibrio in Douala including location at the mouth of Wouri delta on the Atlantic Ocean, sandy clay soil, shallow dirty polluted foul-smelling groundwater, presence of vast expanses of swamp, streams/drainage ditches infested with algae, and high temperatures with low rainfall and drought during certain periods of the year. Most outbreaks have started in Bepanda, a slum area built on a garbage dump in a swampy zone fed by drainage ditches carrying the faecal pollution from neighbouring upstream districts. It is a densely overcrowded area of uncontrolled urbanization generated by the influx of poor city new-comers who live without adequate access to clean water or basic sanitary facilities. The most affected areas are those resulting from recent unregulated urban sprawl in polluted swamp zones or garbage dumps. Since access to the public water system is inadequate with only 65000 persons connected for 3 million inhabitants, dwellers in most areas must take water from the 70000 urban wells (estimated in 2004) that are often not more than 1.5 m deep. Sewage facilities are insufficient to provide complete evacuation of solid and liquid waste. The network of rivers, streams and man-made ditches waste are poorly maintained and often overflow during the rainy season. The contents of latrines are often discharged directly into the environment. Social factors such as the reformation of urban tribes and persistence of traditional attitudes toward waste disposal and water use have not only led to high-risk behaviour but also created barriers to sanitation and hygiene education. With an inadequate sanitation inspection system, a large but purely accessible public health system and a highly disorganized private health sector exists, effective preventive measures are difficult to implement. The combination of these factors probably account for the endemicity of

  7. Geodynamics of oceanic plateau and plume head accretion and their role in Phanerozoic orogenic systems of China

    Directory of Open Access Journals (Sweden)

    Peter G. Betts

    2015-01-01

    Full Text Available We present three 3D numerical models of deep subduction where buoyant material from an oceanic plateau and a plume interact with the overriding plate to assess the influence on subduction dynamics, trench geometry, and mechanisms for plateau accretion and continental growth. Transient instabilities of the convergent margin are produced, resulting in: contorted trench geometry; trench migration parallel with the plate margin; folding of the subducting slab and orocline development at the convergent margin; and transfer of the plateau to the overriding plate. The presence of plume material beneath the oceanic plateau causes flat subduction above the plume, resulting in a “bowed” shaped subducting slab. In plateau-only models, plateau accretion at the edge of the overriding plate results in trench migration around the edge of the plateau before subduction is re-established directly behind the trailing edge of the plateau. The plateau shortens and some plateau material subducts. The presence of buoyant plume material beneath the oceanic plateau has a profound influence on the behaviour of the convergent margin. In the plateau + plume model, plateau accretion causes rapid trench advance. Plate convergence is accommodated by shearing at the base of the plateau and shortening in the overriding plate. The trench migrates around the edge of the plateau and subduction is re-established well behind the trailing edge of the plateau, effectively embedding the plateau into the overriding plate. A slab window forms beneath the accreted plateau and plume material is transferred from the subducting plate to the overriding plate through the window. In all of the models, the subduction zone maintains a relatively stable configuration away from the buoyancy anomalies within the downgoing plate. The models provide a dynamic context for plateau and plume accretion in Phanerozoic accretionary orogenic systems such as the East China Orogen and the Central Asian

  8. Extensional Seismogenic Stress and Tectonic Movement on the Central Region of the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Jiren Xu

    2009-01-01

    Full Text Available Various earthquake fault types, mechanism solutions and stress fields, as well as GPS and geothermal data are analyzed for the study of the crustal movements on the Tibetan plateau and their tectonic implications. The results show that a lot of the normal faulting type-event concentrated at altitudes greater than 4000 m on the central Tibetan plateau. The altitudes concentrating normal faulting type-events can be zoned two parts: the western part, the Lhasa block, and the eastern part, the Qiangtang-Changdu region. The azimuths of T-axes are in a general E-W direction in the Lhasa block and NW-SE or NNW-SSE in the Qiangtang-Changdu region at the altitudes of the Tibetan plateau. The tensional stresses in E-W direction and NW-SE direction predominate normal faulting earthquake occurrence in the Lhasa block and the Qiangtang-Changdu region, respectively. The slipping displacements of the normal-faulting-type events have great components in near E-W direction and NW-SE direction in the Lhasa block and the Qiangtang-Changdu region, respectively. The extensions are probably an eastward or southeastward extensional motion, being mainly tectonic activity phenomena in the plateau altitudes. The extensional motions due to normal-fault earthquakes are important tectonic activity regimes on the high altitudes of the plateau. The easterly crustal extensions on the plateau are attributable to the gravitational collapse of the high plateau and eastward extrusion of hotter mantle materials beneath the eastern boundary of the plateau. Numbers of thrust-fault and strike-slip-fault earthquakes with strong compressive stress in a general NNE-SSW direction occur on the edges of the plateau.

  9. Genetic evidence of paleolithic colonization and neolithic expansion of modern humans on the tibetan plateau.

    Science.gov (United States)

    Qi, Xuebin; Cui, Chaoying; Peng, Yi; Zhang, Xiaoming; Yang, Zhaohui; Zhong, Hua; Zhang, Hui; Xiang, Kun; Cao, Xiangyu; Wang, Yi; Ouzhuluobu; Basang; Ciwangsangbu; Bianba; Gonggalanzi; Wu, Tianyi; Chen, Hua; Shi, Hong; Su, Bing

    2013-08-01

    Tibetans live on the highest plateau in the world, their current population size is approximately 5 million, and most of them live at an altitude exceeding 3,500 m. Therefore, the Tibetan Plateau is a remarkable area for cultural and biological studies of human population history. However, the chronological profile of the Tibetan Plateau's colonization remains an unsolved question of human prehistory. To reconstruct the prehistoric colonization and demographic history of modern humans on the Tibetan Plateau, we systematically sampled 6,109 Tibetan individuals from 41 geographic populations across the entire region of the Tibetan Plateau and analyzed the phylogeographic patterns of both paternal (n = 2,354) and maternal (n = 6,109) lineages as well as genome-wide single nucleotide polymorphism markers (n = 50) in Tibetan populations. We found that there have been two distinct, major prehistoric migrations of modern humans into the Tibetan Plateau. The first migration was marked by ancient Tibetan genetic signatures dated to approximately 30,000 years ago, indicating that the initial peopling of the Tibetan Plateau by modern humans occurred during the Upper Paleolithic rather than Neolithic. We also found evidences for relatively young (only 7-10 thousand years old) shared Y chromosome and mitochondrial DNA haplotypes between Tibetans and Han Chinese, suggesting a second wave of migration during the early Neolithic. Collectively, the genetic data indicate that Tibetans have been adapted to a high altitude environment since initial colonization of the Tibetan Plateau in the early Upper Paleolithic, before the last glacial maximum, followed by a rapid population expansion that coincided with the establishment of farming and yak pastoralism on the Plateau in the early Neolithic.

  10. Active shortening, intermontane basin formation, and geomorphic evolution in an orogenic plateau: Central Puna Plateau, NW Argentina (24°37'S, 67°03'W)

    Science.gov (United States)

    Strecker, Manfred R.; Alonso, Ricardo N.; Bookhagen, Bodo; Freymark, Jessica; Pingel, Heiko

    2017-04-01

    The high-elevation Andean Plateau (Altiplano-Puna; 4km) is a first-order morphotectonic province of the Central Andes and constitutes the world's second largest orogenic plateau. While there are many unifying basin characteristics in this region, including internal drainage, semi-arid to arid climate and associated deposition of evaporites, there are notable differences between the northern and southern parts of the plateau. In contrast to the vast basins of the Altiplano (north) and incipient establishment of fluvial connectivity and sediment transport to the foreland, the Puna (south) comprises numerous smaller basins, bordered by reverse-fault bounded ranges up to 6 km high. The plateau is internally drained and fluvial connectivity with the foreland does not exist leading to thick sedimentary basin fills that comprise continental evaporites, volcanic and clastic deposits, typically between 3 and 5 km thick. However, repeated impacts of climate change and superposed tectonic activity in the southern plateau have resulted in further basin differentiation, abandonment or re-arrangement of fluvial networks and impacts on sediment transport. Here we report evidence for sustained contractional tectonic activity in the Pocitos Basin in the southern plateau. On the western margin of the basin fanning of dipping strata and regraded, steeply inclined gravel-covered pediment surfaces and wind gaps associated with gravel derived from distant sources in the west document late Tertiary to Pleistocene growth of an approximately N-S oriented and N plunging anticline. The growth of the eastern limb of this anticline has caused the isolation of a formerly more extensive basin. In addition, Late Pleistocene and Holocene lake shorelines and lacustrine deposits are tilted eastward along the same structure and InSAR measurements of deformed lake terraces document that the fold is growing. Despite widely reported extensional faulting in the southern Puna, we conclude (1) that the

  11. Repair of potentially lethal damage in unfed plateau phase cultures of Ehrlich ascited tumour cells

    International Nuclear Information System (INIS)

    Illiakis, G.

    1980-01-01

    Plateau phase EAT-cells have been irradiated at different times in the plateau phase and their ability to repair PLD has been measured. A large capacity to repair PLD has been observed if the cultures were kept in the plateau phase for some hours after irradiation before diluting and plating to measure the survival. In combination with theoretical considerations it is concluded that almost all the PLD produced under these conditions can be repaired. The reaction rate of this repair was independent of the dose and the age of the culture. The results also indicate that PLD repair is independent of the intercellular contact of EAT-cells. (author)

  12. Stability analysis of the endemic equilibrium state of an infection age ...

    African Journals Online (AJOL)

    In this work we present an infection-age-structured mathematical model of AIDS disease dynamics and examine the endemic equilibrium state for stability. An explicit formula for the basic reproduction number R0 was obtained in terms of the demographic and epidemiological parameters of the model. The endemic ...

  13. Assessing malaria transmission in a low endemicity area of north-western Peru

    DEFF Research Database (Denmark)

    Rosas-Aguirre, Angel; Llanos-Cuentas, Alejandro; Speybroeck, Niko

    2013-01-01

    Where malaria endemicity is low, control programmes need increasingly sensitive tools for monitoring malaria transmission intensity (MTI) and to better define health priorities. A cross-sectional survey was conducted in a low endemicity area of the Peruvian north-western coast to assess the MTI u...

  14. Molecular identification of Echinococcus species from eastern and southern Qinghai, China, based on the mitochondrial cox1 gene.

    Science.gov (United States)

    Ma, Junying; Wang, Hu; Lin, Gonghua; Craig, Philip S; Ito, Akira; Cai, Zhenyuan; Zhang, Tongzuo; Han, Xiumin; Ma, Xiao; Zhang, Jingxiao; Liu, Yufang; Zhao, Yanmei; Wang, Yongshun

    2012-07-01

    The Qinghai-Tibetan Plateau (QTP, in western China), which is the largest and highest plateau on Earth, is a highly epidemic region for Echinococcus spp. We collected 70 Echinococcus samples from humans, dogs, sheep, yaks, plateau pikas, and voles in eastern and southern Qinghai and genotyped them using the mitochondrial DNA marker cytochrome oxidase subunit I gene and maximum parsimony and Bayesian reconstruction methods. Based on the 792-bp sequence matrix, we recorded 124 variable sites, of which, 115 were parsimony-informative. Thirty-four haplotypes (H1-H34) were detected, of which H1-H15, H16-H17, and H18-H34 belonged to Echinococcus shiquicus, Echinococcus multilocularis, and Echinococcus granulosus, respectively. Within 26 human isolates, three were identified as E. multilocularis and 23 were E. granulosus. We also detected a dual infection case in a dog with E. multilocularis and E. granulosus. The intraspecific haplotype (Hd ± SD) and nucleotide (Nd ± SD) diversity of E. shiquicus (0.947 ± 0.021; 0.00441 ± 0.00062) was higher than that for E. granulosus (0.896 ± 0.038; 0.00221 ± 0.00031) and E. multilocularis (0.286 ± 0.196; 0.00036 ± 0.00025). Moreover, the haplotype network of E. shiquicus showed a radial feature rather than a divergent feature in a previous study, indicating this species in the QTP has also evolved with bottleneck effects.

  15. Optical Observing Conditions at Delingha Station

    Science.gov (United States)

    Tian, J. F.; Deng, L. C.; Zhang, X. B.; Lu, X. M.; Sun, J. J.; Liu, Q. L.; Zhou, Q.; Yan, Z. Z.; Xin, Y.; Wang, K.; Jiang, X. J.; Luo, Z. Q.; Yang, J.

    2016-10-01

    SONG is a global ground-based network of 1m telescopes for stellar time-domain science, an international collaboration involving many countries across the world. In order to enable a favorable duty cycle, the SONG network plans to create a homogeneous distribution of four nodes in each of the northern and southern hemispheres. An expected possibility was building one of the northern nodes in East Asia, preferably on the Qinghai-Tibetan Plateau. During the last decade, a great deal of effort has been invested in searching for a high-quality site for ground-based astronomy in China, since this has been one of the major concerns for the development of Chinese astronomy. A number of sites on the plateau have been in operation for many years, but most of them are used only for radio astronomy, as well as small optical telescopes that are used for applied astronomy. Several potential sites for large optical instruments have been identified by the plateau site survey, but so far none of them have been adequately quantitatively characterized. Here we present results from a detailed multi-year study of the Delingha site, which was eventually selected for the SONG-China node. We also describe the site-monitoring system that will allow an isolated SONG and 50BiN node to operate safely in an automated mode.

  16. A review of the Nearctic genus Zealeuctra Ricker (Plecoptera, Leuctridae), with the description of a new species from the Cumberland Plateau region of eastern North America.

    Science.gov (United States)

    Grubbs, Scott A; Kondratieff, Boris C; Stark, Bill P; Dewalt, R Edward

    2013-01-01

    The stonefly genus Zealeuctra (Plecoptera: Leuctridae) is endemic to the central and eastern Nearctic regions and is presently comprised of 10 species. Scanning electron microscopy (SEM) was used to examine and redescribe two important diagnostic features typically used to identify and define the adult male stage: the large, anteriorly-recurved epiproct and the medial cleft of the ninth abdominal tergite. SEM was also employed to depict the posteromedial portion of female 7(th) sternum. A new species, Z. ukayodi sp. n., is described from the Cumberland Plateau region of northeastern Alabama and Tennessee. The new species appears superficially similar to Z. talladega Grubbs, but is easily differentiated by characteristics of the male medial cleft. An updated taxonomic key to the males of Zealeuctra is provided.

  17. A review of the Nearctic genus Zealeuctra Ricker (Plecoptera, Leuctridae, with the description of a new species from the Cumberland Plateau region of eastern North America

    Directory of Open Access Journals (Sweden)

    Scott Grubbs

    2013-10-01

    Full Text Available The stonefly genus Zealeuctra (Plecoptera: Leuctridae is endemic to the central and eastern Nearctic regions and is presently comprised of 10 species. Scanning electron microscopy (SEM was used to examine and redescribe two important diagnostic features typically used to identify and define the adult male stage: the large, anteriorly-recurved epiproct and the medial cleft of the ninth abdominal tergite. SEM was also employed to depict the posteromedial portion of female 7th sternum. A new species, Z. ukayodi sp. n., is described from the Cumberland Plateau region of northeastern Alabama and Tennessee. The new species appears superficially similar to Z. talladega Grubbs, but is easily differentiated by characteristics of the male medial cleft. An updated taxonomic key to the males of Zealeuctra is provided.

  18. Plant diversity on high elevation islands – drivers of species richness and endemism

    Directory of Open Access Journals (Sweden)

    Severin D.H. Irl

    2016-10-01

    Full Text Available High elevation islands elicit fascination because of their large array of endemic species and strong environmental gradients. First, I define a high elevation island according to geographic and environmental characteristics. Then, within this high elevation island framework, I address local disturbance effects on plant distribution, drivers of diversity and endemism on the island scale, and global patterns of treeline elevation and climate change. Locally, introduced herbivores have strong negative effects on the summit scrub of my model island La Palma (Canary Islands, while roads have unexpected positive effects on endemics. On the island scale, topography and climate drive diversity and endemism. Hotspots of endemicity are found in summit regions – a general pattern on high elevation islands. The global pattern of treeline elevation behaves quite differently on islands than on the mainland. A thorough literature review and climate projections suggest that climate change will profoundly affect oceanic island floras.

  19. Vegetation stability and the habitat associations of the endemic taxa of the Olympic Peninsula, Washington, USA

    Directory of Open Access Journals (Sweden)

    Daniel G. Gavin

    2015-07-01

    Full Text Available Explanations for areas of endemism often involve relative climatic stability, or low climate velocity, over time scales ranging from the Pleistocene to the late Cenozoic. Given that many narrowly endemic taxa in forested landscapes display discrete habitat associations, habitat stability should be similarly important for endemic persistence. Furthermore, while past climate variability is exceedingly difficult to quantify on millennial time scales, past distributions of habitats may be robustly inferred from paleoecological records. The Olympic Peninsula, Washington, supports a biota with several insular features including 29 endemic plant and animal taxa. Here I present the geographic distribution and habitat of the endemic taxa, and then examine the vegetation stability of the past 14,300 years from five pollen records associated with discrete vegetation zones on the peninsula. I show that 11 endemics have distributions centered on dry alpine scree and rock in the northeastern quadrant of the peninsula, and nine occur in shaded riparian forests in the southwest. Vegetation turnover during the post-glacial period was smallest in these areas. However, another long pollen record from the western peninsula reveals existence of shrub tundra and greatly reduced forest cover, indicating southward displacement of shaded riparian habitats by perhaps as much as 100 km. Although this study supports an association of post-glacial vegetation stability with endemism, records spanning the glacial maximum indicate widespread tundra during long periods of the late Pleistocene and therefore suggest southern displacement of forest-associated endemics. While some of the alpine scree-associated endemics may have persisted in situ, many others likely arrived via a variety of dispersal trajectories. These histories include dispersal from southern refugia towards ocean barriers preventing further northward dispersal, contraction from more widespread distributions, and

  20. Inferring the biogeographic origins of inter-continental disjunct endemics using a Bayes-DIVA approach

    Institute of Scientific and Technical Information of China (English)

    AJ HARRIS; Jun WEN; Qiu-Yun (Jenny) XIANG

    2013-01-01

    The arcto-Tertiary relictual flora is comprised of many genera that occur non-contiguously in the temperate zones of eastern Asia,Europe,eastern North America,and westem North America.Within each distributional area,species are typically endemic and may thus be widely separated from closely related species within the other areas.It is widely accepted that this common pattern of distribution resulted from of the fragmentation of a once morecontinuous arcto-Tertiary forest.The historical biogeographic events leading to the present-day disjunction have often been investigated using a phylogenetic approach.Limitations to these previous studies have included phylogenetic uncertainty and uncertainty in ancestral range reconstructions.However,the recently described Bayes-DIVA method handles both types of uncertainty.Thus,we used Bayes-DIVA analysis to reconstruct the stem lineage distributions for 185 endemic lineages from 23 disjunct genera representing 17 vascular plant families.In particular,we asked whether endemic lineages within each of the four distributional areas more often evolved from (1) widespread ancestors,(2) ancestors dispersed from other areas,or (3) endemic ancestors.We also considered which of these three biogeographic mechanisms may best explain the origins of arcto-Tertiary disjunct endemics in the neotropics.Our results show that eastern Asian endemics more often evolved from endemic ancestors compared to endemics in Europe and eastern and western North America.Present-day endemic lineages in the latter areas more often arose from widespread ancestors.Our results also provide anecdotal evidence for the importance of dispersal in the biogeographic origins of arcto-Tertiary species endemic in the neotropics.

  1. Climatic Changes on Tibetan Plateau Based on Ice Core Records

    Science.gov (United States)

    Yao, T.

    2008-12-01

    Climatic changes have been reconstructed for the Tibetan Plateau based on ice core records. The Guliya ice core on the Tibetan Plateau presents climatic changes in the past 100,000 years, thus is comparative with that from Vostok ice core in Antarctica and GISP2 record in Arctic. These three records share an important common feature, i.e., our climate is not stable. It is also evident that the major patterns of climatic changes are similar on the earth. Why does climatic change over the earth follow a same pattern? It might be attributed to solar radiation. We found that the cold periods correspond to low insolation periods, and warm periods to high insolation periods. We found abrupt climatic change in the ice core climatic records, which presented dramatic temperature variation of as much as 10 °C in 50 or 60 years. Our major challenge in the study of both climate and environment is that greenhouse gases such as CO2, CH4 are possibly amplifying global warming, though at what degree remains unclear. One of the ways to understand the role of greenhouse gases is to reconstruct the past greenhouse gases recorded in ice. In 1997, we drilled an ice core from 7100 m a.s.l. in the Himalayas to reconstruct methane record. Based on the record, we found seasonal cycles in methane variation. In particular, the methane concentration is high in summer, suggestiing active methane emission from wet land in summer. Based on the seasonal cycle, we can reconstruct the methane fluctuation history in the past 500 years. The most prominent feature of the methane record in the Himalayan ice core is the abrupt increase since 1850 A.D.. This is closely related to the industrial revolution worldwide. We can also observe sudden decrease in methane concentration during the World War I and World War II. It implies that the industrial revolution has dominated the atmospheric greenhouse gas emission for about 100 years. Besides, the average methane concentration in the Himalayan ice core is

  2. Review of climate and cryospheric change in the Tibetan Plateau

    International Nuclear Information System (INIS)

    Kang Shichang; Xu Yanwei; You Qinglong; Yao Tandong; Fluegel, Wolfgang-Albert; Pepin, Nick

    2010-01-01

    The Tibetan Plateau (TP), with an average elevation of over 4000 m asl and an area of approximately 2.5 x 10 6 km 2 , is the highest and most extensive highland in the world and has been called the 'Third Pole'. The TP exerts a huge influence on regional and global climate through thermal and mechanical forcing mechanisms. Because the TP has the largest cryospheric extent outside the polar region and is the source region of all the large rivers in Asia, it is widely recognized to be the driving force for both regional environmental change and amplification of environmental changes on a global scale. Within China it is recognized as the 'Asian water tower'. In this letter, we summarize the recent changes observed in climate elements and cryospheric indicators on the plateau before discussing current unresolved issues concerning climate change in the TP, including the temporal and spatial components of this change, and the consistency of change as represented by different data sources. Based on meteorological station data, reanalyses and remote sensing, the TP has shown significant warming during the last decades and will continue to warm in the future. While the warming is predominantly caused by increased greenhouse gas emissions, changes in cloud amount, snow-albedo feedback, the Asian brown clouds and land use changes also partly contribute. The cryosphere in the TP is undergoing rapid change, including glacier retreat, inconsistent snow cover change, increasing permafrost temperatures and degradation, and thickening of the active layer. Hydrological processes impacted by glacial retreat have received much attention in recent years. Future attention should be paid to additional perspectives on climate change in the TP, such as the variations of climate extremes, the reliability of reanalyses and more detailed comparisons of reanalyses with surface observations. Spatial issues include the identification of whether an elevational dependency and weekend effect exist

  3. Geomorphological investigations and GIS approach of the Tamiš loess plateau, Banat region (northern Serbia

    Directory of Open Access Journals (Sweden)

    Popov Dragan

    2012-01-01

    Full Text Available The focus of this study was the loess plateau located in the Tamiš River valley in the central part of Banat region (northern Serbia. This morphologic unit has been formed by the loess accumulation process during the last two glacial periods. Digital elevation model (DEM is based on the 1:25.000 scale topographic maps. Detailed geomorphologic and hypsometric maps are provided with selected cross sections. The borders of the plateau and spatial distribution of the micromorphology are precisely defined on DEM. The plateau rises gradually from the Upper Pleistocene terrace on the north and northwest, while to the east and south slopes and vertical bluffs were controlled by the lateral erosion process of surrounding channels and by the weathering process on the loess. The plateau has an atypical morphology characterized by reduced geomorphologic diversity. Loess topography is significantly flattened by human impact. Its micromorphology is characterised by shallow depressions and gullies.

  4. Impact of Cataract Surgery on Quality of Life in Plateau State, Nigeria

    African Journals Online (AJOL)

    Impact of Cataract Surgery on Quality of Life in Plateau State, Nigeria. ... The study instrument was the standardized Visual Function (VF-14) and Quality of ... Outcome Research Team (PORT), and designed to measure the impact of impaired ...

  5. Fixation of tibial plateau fractures with synthetic bone graft versus natural bone graft: a comparison study.

    LENUS (Irish Health Repository)

    Ong, J C Y

    2012-06-01

    The goal of this study was to determine differences in fracture stability and functional outcome between synthetic bone graft and natural bone graft with internal fixation of tibia plateau metaphyseal defects.

  6. The Application of Chaos Theory to the Career-Plateaued Worker.

    Science.gov (United States)

    Duffy, Jean Ann

    2000-01-01

    Applies some of the principles of chaos theory to career-plateaued workers on the basis of a case study. Concludes that chaos theory provides career practitioners a useful application for working with this type of client. (Author/JDM)

  7. A study of the bone healing kinetics of plateau versus screw root design titanium dental implants.

    LENUS (Irish Health Repository)

    Leonard, Gary

    2009-03-01

    This study was designed to compare the bone healing process around plateau root from (PRF) and screw root from (SRF) titanium dental implants over the immediate 12 week healing period post implant placement.

  8. THE LONG-LIVED UV ''PLATEAU'' OF SN 2012aw

    Energy Technology Data Exchange (ETDEWEB)

    Bayless, Amanda J.; Roming, Peter W. A. [Southwest Research Institute, Department of Space Science, 6220 Culebra Road, San Antonio, TX 78238 (United States); Pritchard, Tyler A. [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA 16802 (United States); Kuin, Paul [Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Brown, Peter J. [Texas A and M University, Department of Physics and Astronomy, College Station, TX 77843-4242 (United States); Botticella, Maria Teresa; Dall' Ora, Massimo [INAF-Osservatorio Astronomico di Capodimonte, via Moiariello 16, I-80131 Napoli (Italy); Frey, Lucille H.; Even, Wesley; Fryer, Chris L. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Maund, Justyn R.; Fraser, Morgan [Astrophysics Research Center, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom)

    2013-02-10

    Observations with the Swift UV Optical Telescope have unambiguously uncovered for the first time a long-lived, UV ''plateau'' in a Type II-P supernova (SN). Although this flattening in slope is hinted at in a few other SNe, due to its proximity and minimal line-of-sight extinction, SN 2012aw has afforded the first opportunity to clearly observe this UV plateau. The observations of SN 2012aw revealed all Swift UV and u-band light curves initially declined rapidly, but 27 days after the explosion the light curves flattened. Some possible sources of the UV plateau are the same thermal process that causes the optical plateau, heating from radioactive decay, or a combination of both processes.

  9. Assessment of continuous gas resources in the Khorat Plateau Province, Thailand and Laos, 2016

    Science.gov (United States)

    Schenk, Christopher J.; Klett, Timothy R.; Mercier, Tracey J.; Finn, Thomas M.; Tennyson, Marilyn E.; Gaswirth, Stephanie B.; Marra, Kristen R.; Le, Phuong A.; Drake, Ronald M.

    2017-05-25

    Using a geology-based assessment methodology, the U.S. Geological Survey assessed mean undiscovered, technically recoverable resources of 2.3 trillion cubic feet of continuous gas in the Khorat Plateau Province of Thailand and Laos.

  10. Element concentrations in surface soils of the Coconino Plateau, Grand Canyon region, Coconino County, Arizona

    Science.gov (United States)

    Van Gosen, Bradley S.

    2016-09-15

    This report provides the geochemical analyses of a large set of background soils collected from the surface of the Coconino Plateau in northern Arizona. More than 700 soil samples were collected at 46 widespread areas, sampled from sites that appear unaffected by mineralization and (or) anthropogenic contamination. The soils were analyzed for 47 elements, thereby providing data on metal concentrations in soils representative of the plateau. These background concentrations can be used, for instance, for comparison to metal concentrations found in soils potentially affected by natural and anthropogenic influences on the Coconino Plateau in the Grand Canyon region of Arizona.The soil sampling survey revealed low concentrations for the metals most commonly of environmental concern, such as arsenic, cobalt, chromium, copper, mercury, manganese, molybdenum, lead, uranium, vanadium, and zinc. For example, the median concentrations of the metals in soils of the Coconino Plateau were found to be comparable to the mean values previously reported for soils of the western United States.

  11. Observation of the Zero Hall Plateau in a Quantum Anomalous Hall Insulator

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Yang; Feng, Xiao; Ou, Yunbo; Wang, Jing; Liu, Chang; Zhang, Liguo; Zhao, Dongyang; Jiang, Gaoyuan; Zhang, Shou-Cheng; He, Ke; Ma, Xucun; Xue, Qi-Kun; Wang, Yayu

    2015-09-16

    We report experimental investigations on the quantum phase transition between the two opposite Hall plateaus of a quantum anomalous Hall insulator. We observe a well-defined plateau with zero Hall conductivity over a range of magnetic field around coercivity when the magnetization reverses. The features of the zero Hall plateau are shown to be closely related to that of the quantum anomalous Hall effect, but its temperature evolution exhibits a significant difference from the network model for a conventional quantum Hall plateau transition. We propose that the chiral edge states residing at the magnetic domain boundaries, which are unique to a quantum anomalous Hall insulator, are responsible for the novel features of the zero Hall plateau.

  12. Neoclassical resonant-plateau transport in the noncircular equipotential surface of a tandem mirror

    International Nuclear Information System (INIS)

    Katanuma, I.; Kiwamoto, Y.; Ishii, K.; Yatsu, K.; Miyoshi, S.

    1988-07-01

    Neoclassical resonant-plateau transport in a minimum-B anchored tandem mirror is calculated in an experimentally observed case that a magnetic flux tube of an equipotential contours is not circular at the central cell. (author)

  13. Neoclassical resonant-plateau transport in the noncircular equipotential surface of a tandem mirror

    International Nuclear Information System (INIS)

    Katanuma, I.; Kiwamoto, Y.; Ishii, K.; Yatsu, K.; Miyoshi, S.

    1989-01-01

    Neoclassical resonant-plateau transport in a minimum-B anchored tandem mirror is calculated in an experimentally observed case where a flux tube of equipotential contours is not circular at the central cell

  14. Conservation status and recovery strategies for endemic Hawaiian birds

    Science.gov (United States)

    Banko, Paul C.; David, Reginald E.; Jacobi, James D.; Banko, Winston E.

    2001-01-01

    Populations of endemic Hawaiian birds declined catastrophically following the colonization of the islands by Polynesians and later cultures. Extinction is still occurring, and recovery programs are urgently needed to prevent the disappearance of many other species. Programs to recover the endemic avifauna incorporate a variety of conceptual and practical approaches that are constrained by biological, financial, social, and legal factors. Avian recovery is difficult to implement in Hawai‘i because a variety of challenging biological factors limit bird populations. Hawaiian birds are threatened by alien predatory mammals, introduced mosquitoes that transmit diseases, alien invertebrate parasites and predators that reduce invertebrate food resources, and alien animals and plants that destroy and alter habitats. Life in the remote Hawaiian Archipelago has imposed other biological constraints to avian recovery, including limited geographical distributions and small population sizes. Recovery of the endemic avifauna is also challenging because resources are insufficient to mitigate the many complex, interacting factors that limit populations. Decisions must be made for allocating limited resources to species teetering on the brink of extinction and those in decline. If funds are spent primarily on saving the rarest species, more abundant species will decline and become more difficult to recover. However, critically rare species will disappear if efforts are directed mainly towards restoring species that are declining but not in immediate danger of becoming extinct. Determining priorities is difficult also because management is needed both to supplement bird populations and to restore habitats of many species. Rare species cannot respond quickly to management efforts intended only to improve habitat and reduce limiting factors. Recovery is slow, if it occurs at all, because years or decades are generally required for habitat rehabilitation and because small populations

  15. Paleodrainage of the Columbia River system on the Columbia Plateau of Washington State: a summary

    International Nuclear Information System (INIS)

    Fecht, K.R.; Reidel, S.P.; Tallman, A.M.

    1985-12-01

    The evolution of the Columbia River drainage system on the Columbia Plateau of Washington in the last 17 My reflects the geologic history of the plateau. We have updated an interpretation of the evolution of the Columbia River system and defined the geomorphic and structural features that have controlled the position of ancestral streams. The sequence of geologic events and the resulting drainage system for various time intervals in the last 17 My are summarized below. 121 refs., 14 figs

  16. Changes in Cerebral Partial Oxygen Pressure and Cerebrovascular Reactivity During Intracranial Pressure Plateau Waves.

    Science.gov (United States)

    Lang, Erhard W; Kasprowicz, Magdalena; Smielewski, Peter; Pickard, John; Czosnyka, Marek

    2015-08-01

    Plateau waves in intracranial pressure (ICP) are frequently recorded in neuro intensive care and are not yet fully understood. To further investigate this phenomenon, we analyzed partial pressure of cerebral oxygen (pbtO2) and a moving correlation coefficient between ICP and mean arterial blood pressure (ABP), called PRx, along with the cerebral oxygen reactivity index (ORx), which is a moving correlation coefficient between cerebral perfusion pressure (CPP) and pbtO2 in an observational study. We analyzed 55 plateau waves in 20 patients after severe traumatic brain injury. We calculated ABP, ABP pulse amplitude (ampABP), ICP, CPP, pbtO2, heart rate (HR), ICP pulse amplitude (ampICP), PRx, and ORx, before, during, and after each plateau wave. The analysis of variance with Bonferroni post hoc test was used to compare the differences in the variables before, during, and after the plateau wave. We considered all plateau waves, even in the same patient, independent because they are separated by long intervals. We found increases for ICP and ampICP according to our operational definitions for plateau waves. PRx increased significantly (p = 0.00026), CPP (p pressure remains stable in ICP plateau waves, while cerebral autoregulatory indices show distinct changes, which indicate cerebrovascular reactivity impairment at the top of the wave. PbtO2 decreases during the waves and may show a slight overshoot after normalization. We assume that this might be due to different latencies of the cerebral blood flow and oxygen level control mechanisms. Other factors may include baseline conditions, such as pre-plateau wave cerebrovascular reactivity or pbtO2 levels, which differ between studies.

  17. Strain transformation between tectonic extrusion and crustal thickening in the growth of the Tibetan Plateau

    Science.gov (United States)

    Liu, M.; Li, Y.; Sun, Y.; Shen, X.

    2017-12-01

    The Indo-Eurasian continental collision since 50 Ma has thickened the crust to raise the Himalayan-Tibetan Plateau and driven lateral extrusion of Asian lithospheric blocks to affect Cenozoic tectonics in central and east Asia. The relative roles of crustal thickening and tectonic extrusion, and the strain partitioning between them over time and space, remain controversial. We have analyzed the strain rates using GPS velocities, and correlated the results with vertical motion derived from precise leveling. We found that tectonic extrusion largely transforms to crustal thickening near the margins of the Tibetan Plateau. Near the NW margin of the Tibetan Plateau, the shear stain transforms to compressive strain, consistent with neotectonic studies that indicate crustal shortening and uplift. Around the SE margin, shear stain largely terminates in the southern Yunnan province of China. The present-day crustal motion in SE Tibetan Plateau can be well explained by gravitational spreading without invoking plate-edge push as envisioned in the tectonic extrusion model. Using data collected from local seismic arrays, we derived receiver functions to image the lithospheric structures across the Tibetan Plateau and the Alashan block to its north and the Ordos block to its east. Our results indicate that the mantle lithosphere of these bounding Asian blocks has not been reworked by Tibetan tectonics; instead they have acted as restrictive walls to the growing Tibetan Plateau. Our finite element modeling shows that crustal deformation along the margins of the Tibetan Plateau are consistent with the notion that the east- and southeastward extrusion of the Tibetan lithosphere is largely confined to the Tibetan Plateau because of the restrictive bounding blocks of the Asian lithosphere. Thus the tectonic impact of the Indo-Eurasian collision on the Cenozoic Asian tectonics may not be as extensive as previously thought.

  18. A pliocene cliff-line around the Giza Pyramids Plateau, Egypt

    OpenAIRE

    Aigner, Thomas

    1982-01-01

    Aigner, T., 1983. A Pliocene cliff-line around the Giza Pyramids Plateau, Egypt. Palaeogeogr., Palaeoclimatol., Palaeoecol., 4 2 : 313—322. Escarpments bordering the Giza Pyramids Plateau represent the cliff-line of a Pliocene transgression up the pre-Nile ("Eonile") Valley. Geomorphologically, a limestone cliff can be distinguished from a slip-block shore associated with a distinct fining-up sequence. Differences in bedrock lithology and in structure (Joint pattern, faults) are morphogen...

  19. COMPARATIVE SPERM ULTRASTRUCTURE OF BAIKALIAN ENDEMIC PROSOBRANCH GASTROPODS.

    Science.gov (United States)

    Ropstorf, PETER; Healy, JOHN M.; Riedel, FRANK; Sitnikova, TATIANA Y.

    2002-05-01

    Mature euspermatozoan ultrastructure is described for seven species of the rissooidean family Baicaliidae (endemic to Lake Baikal, Russia)-Liobaicalia stiedae, Teratobaikalia ciliata, T. macrostoma, Baicalia carinata, Pseudobaikalia pulla, Maackia bythiniopsis, M. variesculpta, and M. herderiana. For comparison with these species and previously investigated Rissooidea, two species of the Lake Baikal endemic genus Benedictia (B. cf. fragilis and B. baicalensis; Hydrobiidae: Benedictiinae of some authors, Benedictiidae of other authors) in addition to Lithoglyphus naticoides (Hydrobiidae: Lithoglyphinae) and Bythinella austriaca (Hydrobiidae: Bythinellinae) were also investigated. Paraspermatozoa were not observed in any of the species examined, supporting the view that these cells are probably absent in the Rissooidea. In general, the euspermatozoa of all species examined resemble those of many other caenogastropods (basally invaginated acrosomal vesicle, mid-piece with 7-13 helical mitochondria, an annulus, glycogen piece with nine peri-axonemal tracts of granules). However, the presence of a completely flattened acrosomal vesicle and a specialized peri-axonemal membranous sheath (a scroll-like arrangement of 4-6 double membranes) at the termination of the mid-piece, clearly indicates a close relationship between the Baicaliidae and other rissooidean families possessing these features (Bithyniidae, Hydrobiidae, Pyrgulidae, and Stenothyridae). Euspermatozoa of Benedictia, Lithoglyphus, Bythinella, and Pyrgula all have a solid nucleus, which exhibits a short, posterior invagination (housing the centriolar complex and proximal portion of the axoneme). Among the Rissooidea, this form of nucleus is known to occur in the Bithyniidae, Hydrobiidae, Truncatellidae, Pyrgulidae, Iravadiidae, Pomatiopsidae, and Stenothyridae. In contrast, the euspermatozoa of the Baicaliidae all have a long, tubular nucleus, housing not only the centriolar derivative, but also a substantial

  20. Importance of dynamic topography in Himalaya-Tibetan plateau region

    Science.gov (United States)

    Ghosh, A.; Singh, S.

    2017-12-01

    Himalaya-Tibetan plateau region has the highest topography in the world. Various studies have been done to understand the mechanisms responsible for sustaining this high topography. However, the existence of dynamic topography in this region is still uncertain, though there have been some studies exploring the role of channel flow in lower crust leading to some topography. We investigated the role of radial mantle flow in this region by studying the relationship between geoid and topography. High geoid-to-topography ratios (GTR) were observed along the Himalayas suggesting deeper compensation mechanisms. However, further north, the geoid and topography relationship became a lot more complex as high as well as low GTR values were observed. The high GTR regions also coincided with area of high filtered free air gravity anomalies, indicating dynamic support. We also looked at the spectral components of gravity, geoid and topography, and calculated response functions to distinguish between different compensation mechanisms. We estimated the average elastic thickness of the whole region to be around 40 km from coherence and admittance studies. The GTR and admittance-coherence studies suggest deeper mass anomalies playing a role in supporting the topography along Himalayas and the area between Altyn Tagh and Kunlun faults.

  1. Motivating Communities To Go Beyond the Discovery Plateau

    Science.gov (United States)

    Habermann, T.; Kozimor, J.

    2014-12-01

    Years of emphasizing discovery and minimal metadata requirements have resulted in a culture that accepts that metadata are for discovery and complete metadata are too complex or difficult for researchers to understand and create. Evolving the culture past this "data-discovery plateau" requires a multi-faceted approach that addresses the rational and emotional sides of the problem. On the rational side, scientists know that data and results must be well documented in order to be reproducible, re-usable, and trustworthy. We need tools that script critical moves towards well-described destinations and help identify members of the community that are already leading the way towards those destinations. We need mechanisms that help those leaders share their experiences and examples. On the emotional side, we need to emphasize that high-quality metadata makes data trustworthy, divide the improvement process into digestible pieces and create mechanisms for clearly identifying and rewarding progress. We also need to provide clear opportunities for community members to increase their expertise and to share their skills.

  2. Drop coalescence and liquid flow in a single Plateau border

    Science.gov (United States)

    Cohen, Alexandre; Fraysse, Nathalie; Raufaste, Christophe

    2015-05-01

    We report a comprehensive study of the flow of liquid triggered by injecting a droplet into a liquid foam microchannel, also called a Plateau border. This drop-injected experiment reveals an intricate dynamics for the liquid redistribution, with two contrasting regimes observed, ruled either by inertia or viscosity. We devoted a previous study [A. Cohen et al., Phys. Rev. Lett. 112, 218303 (2014), 10.1103/PhysRevLett.112.218303] to the inertial imbibition regime, unexpected at such small length scales. Here we report other features of interest of the drop-injected experiment, related to the coalescence of the droplet with the liquid microchannel, to both the inertial and viscous regimes, and to the occurrence of liquid flow through the soap films as well as effects of the interfacial rheology. The transition between the two regimes is investigated and qualitatively accounted for. The relevance of our results to liquid foam drainage is tackled by considering the flow of liquid at the nodes of the network of interconnected microchannels. Extensions of our study to liquid foams are discussed.

  3. Magnetotelluric data, Taos Plateau Volcanic Field, New Mexico

    Science.gov (United States)

    Ailes, Chad E.; Rodriguez, Brian D.

    2010-01-01

    The population of the San Luis Basin region of northern New Mexico is growing. Water shortfalls could have serious consequences. Future growth and land management in the region depend on accurate assessment and protection of the region's groundwater resources. An important issue in managing the groundwater resources is a better understanding of the hydrogeology of the Santa Fe Group and the nature of the sedimentary deposits that fill the Rio Grande rift, which contain the principal groundwater aquifers. The shallow unconfined aquifer and the deeper confined Santa Fe Group aquifer in the San Luis Basin are the main sources of municipal water for the region. The U.S. Geological Survey (USGS) is conducting a series of multidisciplinary studies of the San Luis Basin. Detailed geologic mapping, high-resolution airborne magnetic surveys, gravity surveys, an electromagnetic survey called magnetotellurics (MT), and hydrologic and lithologic data are being used to better understand the aquifers. This report describes a regional east-west MT sounding profile acquired in late July 2009 across the Taos Plateau Volcanic Field where drillhole data are sparse. Resistivity modeling of the MT data can be used to help map changes in electrical resistivity with depths that are related to differences in rock types. These various rock types help control the properties of aquifers. The purpose of this report is to release the MT sounding data collected along the east-west profile. No interpretation of the data is included.

  4. Seismicity of the Paradox Basin and the Colorado Plateau interior

    International Nuclear Information System (INIS)

    Wong, I.G.

    1984-04-01

    National Waste Terminal Storage Program site qualification criteria require that a nuclear waste repository be located so that ground motion associated with the maximum credible and maximum probable earthquakes or other earthquake-associated effects will not have an unacceptable adverse impact on system performance. To determine whether a potential repository site located in the Paradox salt formation in the Paradox Basin of southeastern Utah satisfies these criteria, seismological studies were undertaken by Woodward-Clyde Consultants (WCC) in March 1978. These studies included: (1) analysis of historical seismicity; (2) analysis of contemporary seismicity and tectonics of both the Paradox Basin and surrounding Colorado Plateau, including an extensive program of microearthquake monitoring; (3) evaluation of the Paradox Basin crustal structure; (4) evaluation of mining-induced seismicity; and (5) characterization of design-related earthquake-induced ground motions pertinent to a potential repository site through studies of attentation and subsurface ground motions. A detailed discussion of the results of the seismological studies performed through December 1980 is contained in WCC (1982). The purpose of this topical report is to update and summarize the studies on the local, regional, and mining-induced seismicity conducted through December 1982. The limitations of any interpretations are also discussed and additional information that remains to be acquired is identified. 56 references, 45 figures, 4 tables

  5. [Clinical practice guideline on closed tibial plateau fractures in adulthood].

    Science.gov (United States)

    Ocegueda-Sosa, Miguel Ángel; Valenzuela-Flores, Adriana Abigail; Aldaco-García, Víctor Daniel; Flores-Aguilar, Sergio; Manilla-Lezama, Nicolás; Pérez-Hernández, Jorge

    2013-01-01

    Closed tibiae plateau fractures are common injuries in the emergency room. The optimal treatment is not well defined or established. For this reason, there are several surgical management options: open reduction and internal fixation, closed reduction and percutaneous synthesis, external fixation, and even conservative treatment for this kind of fracture. The mechanism of production of this fracture is through large varus or valgus deformation to which is added a factor of axial load. The trauma may be direct or indirect. The degree of displacement, fragmentation and involvement of soft tissues like ligaments, menisci, vascular and nerve structures are determined by the magnitude of the force exerted. Any intra-articular fracture treatment can lead to an erroneous instability, deformity and limitation of motion with subsequent arthritic changes, leading to joint incongruity, limiting activity and significantly altering the quality of life. Open reduction and internal fixation with anatomic restitution is the method used in this type of fracture. However, the results of numerous publications can be questioned due to the inclusion in the same study of fractures treated with very different methods.

  6. Warming slowdown over the Tibetan plateau in recent decades

    Science.gov (United States)

    Liu, Yaojie; Zhang, Yangjian; Zhu, Juntao; Huang, Ke; Zu, Jiaxing; Chen, Ning; Cong, Nan; Stegehuis, Annemiek Irene

    2018-03-01

    As the recent global warming hiatus and the warming on high elevations are attracting worldwide attention, this study examined the robustness of the warming slowdown over the Tibetan plateau (TP) and its related driving forces. By integrating multiple-source data from 1982 to 2015 and using trend analysis, we found that the mean temperature (T mean), maximum temperature (T max) and minimum temperature (T min) showed a slowdown of the warming trend around 1998, during the period of the global warming hiatus. This was found over both the growing season (GS) and non-growing season (NGS) and suggested a robust warming hiatus over the TP. Due to the differences in trends of T max and T min, the trend of diurnal temperature range (DTR) also shifted after 1998, especially during the GS temperature. The warming rate was spatially heterogeneous. The northern TP (NTP) experienced more warming than the southern TP (STP) in all seasons from 1982 to 1998, while the pattern was reversed in the period from 1998 to 2015. Water vapour was found to be the main driving force for the trend in T mean and T min by influencing downward long wave radiation. Sunshine duration was the main driving force behind the trend in T max and DTR through a change in downward shortwave radiation that altered the energy source of daytime temperature. Water vapour was the major driving force for temperature change over the NTP, while over the STP, sunshine duration dominated the temperature trend.

  7. New Hf-Nd evidence supports a heterogeneous plume source for the Caribbean Plateau

    International Nuclear Information System (INIS)

    Thompson, P.M.E; Kempton, P.D; White, R.V; Kerr, A.C; Tarney, J.; Sauders, A.D

    2001-01-01

    Hf-Nd systematics provide us with a valuable tool for tracing mantle sources and signatures in ancient or altered rocks. Hf and Nd are amongst the most resistant of all elements to secondary alteration processes (Pearce et al., 1999) and hence can give us insights into the source compositions of altered plateau basalts that other isotopic systems will not. Here we use Hf-Nd systematics to probe the depths of the Cretaceous Caribbean Plateau, in order to characterise its isotope systematics, and hence determine the geochemical nature of the mantle plume responsible for its formation. Much of the plateau is already well characterised in terms of trace elements and isotopes such as Sr, Nd, Pb and Os (Kerr et al., 1997; White et al., 1999; Walker et al., 1999). Unfortunately, isotope system resetting due to sub- solidus alteration, amongst other factors, has ensured that these isotopes have been inconclusive in resolving many important issues, such as whether the Caribbean plateau is a product of an earlier Galapagos plume phase, and how the apparently unique Gorgona komatiites relate to the rest of the Caribbean plateau. We present new Hf-Nd isotopic data which reveal that the Caribbean plume must have been compositionally heterogeneous, comprising at least three different source components. We then compare this 'Caribbean plume' to other present-day plumes, (e.g. Galapagos) and from this speculate whether initial magmatism from the Galapagos plume could indeed have been responsible for the formation of the Caribbean Plateau (au)

  8. Spatial and temporal variation of tectonic uplift in the southeastern Ethiopian Plateau from morphotectonic analysis

    Science.gov (United States)

    Xue, Liang; Alemu, Tadesse; Gani, Nahid D.; Abdelsalam, Mohamed G.

    2018-05-01

    We use morphotectonic analysis to study the tectonic uplift history of the southeastern Ethiopian Plateau (SEEP). Based on studies conducted on the Northwestern Ethiopian Plateau, steady-state and pulsed tectonic uplift models were proposed to explain the growth of the plateau since 30 Ma. We test these two models for the largely unknown SEEP. We present the first quantitative morphotectonic study of the SEEP. First, in order to infer the spatial distribution of the tectonic uplift rates, we extract geomorphic proxies including normalized steepness index ksn, hypsometric integral HI, and chi integral χ from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) digital elevation model (DEM). Second, we compare these rates with the thickness of flood basalt that we estimated from geological maps. Third, to constrain the timing of regional tectonic uplift, we develop a knickpoint celerity model. Fourth, we compare our results to those from the Northwestern Ethiopian Plateau to suggest a possible mechanism to explain regional tectonic uplift of the entire Ethiopian Plateau. We find an increase in tectonic uplift rates from the southeastern escarpments of the Afar Depression in the northeast to that of the Main Ethiopian Rift to the southwest. We identify three regional tectonic uplift events at 11.7, 6.5, and 4.5 Ma recorded by the development of regionally distributed knickpoints. This is in good agreement with ages of tectonic uplift events reported from the Northwestern Ethiopian Plateau.

  9. Aligning conservation goals: are patterns of species richness and endemism concordant at regional scales?

    Directory of Open Access Journals (Sweden)

    Ricketts, T. H.

    2001-01-01

    Full Text Available Biodiversity conservation strategies commonly target areas of high species richness and/or high endemism. However, the correlation between richness and endemism at scales relevant to conservation is unclear; these two common goals of conservation plans may therefore be in conflict. Here the spatial concordance between richness and endemism is tested using five taxa in North America: butterflies, birds, mammals, amphibians, and reptiles. This concordance is also tested using overall indices of richness and endemism (incorporating all five taxa. For all taxa except birds, richness and endemism were significantly correlated, with amphibians, reptiles, and the overall indices showing the highest correlations (rs = 0.527-0.676. However, 'priority sets' of ecoregions (i.e., the top 10% of ecoregions based on richness generally overlapped poorly with those based on endemism (< 50% overlap for all but reptiles. These results offer only limited support for the idea that richness and endemism are correlated at broad scales and indicate that land managers will need to balance these dual, and often conflicting, goals of biodiversity conservation.

  10. Endemic Acinetobacter baumannii in a New York hospital.

    Directory of Open Access Journals (Sweden)

    Scott A Weisenberg

    Full Text Available Acinetobacter baumannii is an increasingly multidrug-resistant (MDR cause of hospital-acquired infections, often associated with limited therapeutic options. We investigated A. baumannii isolates at a New York hospital to characterize genetic relatedness.Thirty A. baumannii isolates from geographically-dispersed nursing units within the hospital were studied. Isolate relatedness was assessed by repetitive sequence polymerase chain reaction (rep-PCR. The presence and characteristics of integrons were assessed by PCR. Metabolomic profiles of a subset of a prevalent strain isolates and sporadic isolates were characterized and compared.We detected a hospital-wide group of closely related carbapenem resistant MDR A. baumannii isolates. Compared with sporadic isolates, the prevalent strain isolates were more likely to be MDR (p = 0.001. Isolates from the prevalent strain carried a novel Class I integron sequence. Metabolomic profiles of selected prevalent strain isolates and sporadic isolates were similar.The A. baumannii population at our hospital represents a prevalent strain of related MDR isolates that contain a novel integron cassette. Prevalent strain and sporadic isolates did not segregate by metabolomic profiles. Further study of environmental, host, and bacterial factors associated with the persistence of prevalent endemic A. baumannii strains is needed to develop effective prevention strategies.

  11. Distinct Viral and Mutational Spectrum of Endemic Burkitt Lymphoma.

    Directory of Open Access Journals (Sweden)

    Francesco Abate

    2015-10-01

    Full Text Available Endemic Burkitt lymphoma (eBL is primarily found in children in equatorial regions and represents the first historical example of a virus-associated human malignancy. Although Epstein-Barr virus (EBV infection and MYC translocations are hallmarks of the disease, it is unclear whether other factors may contribute to its development. We performed RNA-Seq on 20 eBL cases from Uganda and showed that the mutational and viral landscape of eBL is more complex than previously reported. First, we found the presence of other herpesviridae family members in 8 cases (40%, in particular human herpesvirus 5 and human herpesvirus 8 and confirmed their presence by immunohistochemistry in the adjacent non-neoplastic tissue. Second, we identified a distinct latency program in EBV involving lytic genes in association with TCF3 activity. Third, by comparing the eBL mutational landscape with published data on sporadic Burkitt lymphoma (sBL, we detected lower frequencies of mutations in MYC, ID3, TCF3 and TP53, and a higher frequency of mutation in ARID1A in eBL samples. Recurrent mutations in two genes not previously associated with eBL were identified in 20% of tumors: RHOA and cyclin F (CCNF. We also observed that polyviral samples showed lower numbers of somatic mutations in common altered genes in comparison to sBL specimens, suggesting dual mechanisms of transformation, mutation versus virus driven in sBL and eBL respectively.

  12. The genome of the Antarctic-endemic copepod, Tigriopus kingsejongensis.

    Science.gov (United States)

    Kang, Seunghyun; Ahn, Do-Hwan; Lee, Jun Hyuck; Lee, Sung Gu; Shin, Seung Chul; Lee, Jungeun; Min, Gi-Sik; Lee, Hyoungseok; Kim, Hyun-Woo; Kim, Sanghee; Park, Hyun

    2017-01-01

    The Antarctic intertidal zone is continuously subjected to extremely fluctuating biotic and abiotic stressors. The West Antarctic Peninsula is the most rapidly warming region on Earth. Organisms living in Antarctic intertidal pools are therefore interesting for research into evolutionary adaptation to extreme environments and the effects of climate change. We report the whole genome sequence of the Antarctic-endemic harpacticoid copepod Tigriopus kingsejongensi . The 37 Gb raw DNA sequence was generated using the Illumina Miseq platform. Libraries were prepared with 65-fold coverage and a total length of 295 Mb. The final assembly consists of 48 368 contigs with an N50 contig length of 17.5 kb, and 27 823 scaffolds with an N50 contig length of 159.2 kb. A total of 12 772 coding genes were inferred using the MAKER annotation pipeline. Comparative genome analysis revealed that T. kingsejongensis -specific genes are enriched in transport and metabolism processes. Furthermore, rapidly evolving genes related to energy metabolism showed positive selection signatures. The T. kingsejongensis genome provides an interesting example of an evolutionary strategy for Antarctic cold adaptation, and offers new genetic insights into Antarctic intertidal biota. © The Author 2017. Published by Oxford University Press.

  13. Gene Expression Signature in Endemic Osteoarthritis by Microarray Analysis

    Directory of Open Access Journals (Sweden)

    Xi Wang

    2015-05-01

    Full Text Available Kashin-Beck Disease (KBD is an endemic osteochondropathy with an unknown pathogenesis. Diagnosis of KBD is effective only in advanced cases, which eliminates the possibility of early treatment and leads to an inevitable exacerbation of symptoms. Therefore, we aim to identify an accurate blood-based gene signature for the detection of KBD. Previously published gene expression profile data on cartilage and peripheral blood mononuclear cells (PBMCs from adults with KBD were compared to select potential target genes. Microarray analysis was conducted to evaluate the expression of the target genes in a cohort of 100 KBD patients and 100 healthy controls. A gene expression signature was identified using a training set, which was subsequently validated using an independent test set with a minimum redundancy maximum relevance (mRMR algorithm and support vector machine (SVM algorithm. Fifty unique genes were differentially expressed between KBD patients and healthy controls. A 20-gene signature was identified that distinguished between KBD patients and controls with 90% accuracy, 85% sensitivity, and 95% specificity. This study identified a 20-gene signature that accurately distinguishes between patients with KBD and controls using peripheral blood samples. These results promote the further development of blood-based genetic biomarkers for detection of KBD.

  14. Vegetative propagation of the Azorean endemic shrub Viburnum treleasei Gand

    Directory of Open Access Journals (Sweden)

    MÓNICA MOURA

    2009-01-01

    Full Text Available Viburnum treleasei Gand. is a threatened hermaphroditic shrub or small tree endemic to the Azores islands. In this study we aimed at defining a fast, simple and cost-efficient propagation methodology that could be used by non-skilled workers in conservation actionplans. Our objective was also to produce cleaner material for initiation of in vitro cultures and to determine the effects of season, placement of cuttings in the branch, placement of vegetative buds in cuttings and forcing solutions in shoot development. It was possible to produce clean shoots from cuttings using a forcing solution with 8-hydroxyquinoline sulphate (8-HQS, 2% sucrose and no growth regulators addition. Shoot development results obtained with apical and sub-apical cuttings indicate that V. treleasei possessesapical dominance and deep endodormancy. Apical semihardwood cuttings in autumn or airlayered branches in autumn and winter with 2 or 5% (w/w of IBA produced excellent rooting results which will allow reinforcing depleted populations of V. treleasei efficientlyand at reduced costs.

  15. Incidence of Endemic Burkitt Lymphoma in Three Regions of Mozambique

    Science.gov (United States)

    O'Callaghan-Gordo, Cristina; Casabonne, Delphine; Carrilho, Carla; Ferro, Josefo; Lorenzoni, Cesaltina; Zaqueu, Clesio; Nhabomba, Augusto; Aguilar, Ruth; Bassat, Quique; de Sanjosé, Sílvia; Dobaño, Carlota; Kogevinas, Manolis

    2016-01-01

    Data on the burden and incidence of endemic Burkitt lymphoma (eBL) across Mozambique are scarce. We retrospectively retrieved information on eBL cases from reports of the three main hospitals of Mozambique: Maputo Central Hospital (MCH), Beira Central Hospital (BCH), and Nampula Central Hospital (NCH) between 2004 and 2014. For 2015, we prospectively collected information of new eBL cases attending these hospitals. A total of 512 eBL cases were reported between 2004 and 2015: 153 eBL cases were reported in MCH, 195 in BCH, and 164 in NCH. Mean age of cases was 6.9 years (standard deviation = 2.8); 63% (319/504) of cases were males. For 2015, the estimated incidence rate of eBL was 2.0, 1.7, and 3.9 per 106 person-year at risk in MCH, BCH, and NCH, respectively. Incidence was higher in NCH (northern Mozambique), where intensity of malaria transmission is higher. Data presented show that eBL is a common pediatric malignancy in Mozambique, as observed in neighboring countries. PMID:27799648

  16. Distinct Viral and Mutational Spectrum of Endemic Burkitt Lymphoma.

    Science.gov (United States)

    Abate, Francesco; Ambrosio, Maria Raffaella; Mundo, Lucia; Laginestra, Maria Antonella; Fuligni, Fabio; Rossi, Maura; Zairis, Sakellarios; Gazaneo, Sara; De Falco, Giulia; Lazzi, Stefano; Bellan, Cristiana; Rocca, Bruno Jim; Amato, Teresa; Marasco, Elena; Etebari, Maryam; Ogwang, Martin; Calbi, Valeria; Ndede, Isaac; Patel, Kirtika; Chumba, David; Piccaluga, Pier Paolo; Pileri, Stefano; Leoncini, Lorenzo; Rabadan, Raul

    2015-10-01

    Endemic Burkitt lymphoma (eBL) is primarily found in children in equatorial regions and represents the first historical example of a virus-associated human malignancy. Although Epstein-Barr virus (EBV) infection and MYC translocations are hallmarks of the disease, it is unclear whether other factors may contribute to its development. We performed RNA-Seq on 20 eBL cases from Uganda and showed that the mutational and viral landscape of eBL is more complex than previously reported. First, we found the presence of other herpesviridae family members in 8 cases (40%), in particular human herpesvirus 5 and human herpesvirus 8 and confirmed their presence by immunohistochemistry in the adjacent non-neoplastic tissue. Second, we identified a distinct latency program in EBV involving lytic genes in association with TCF3 activity. Third, by comparing the eBL mutational landscape with published data on sporadic Burkitt lymphoma (sBL), we detected lower frequencies of mutations in MYC, ID3, TCF3 and TP53, and a higher frequency of mutation in ARID1A in eBL samples. Recurrent mutations in two genes not previously associated with eBL were identified in 20% of tumors: RHOA and cyclin F (CCNF). We also observed that polyviral samples showed lower numbers of somatic mutations in common altered genes in comparison to sBL specimens, suggesting dual mechanisms of transformation, mutation versus virus driven in sBL and eBL respectively.

  17. Endemic pemphigus foliaceus over a century: Part I.

    Science.gov (United States)

    Abréu-Vélez, Ana María; Reason, Iara J de Messias; Howard, Michael S; Roselino, Ana Maria

    2010-02-01

    Endemic pemphigus foliaceus (EPF) is the only known autoimmune disease presenting in circumscribed geographic areas. We aim to provide information concerning the natural course of EPF, including systemic compromise in the presteroid era, which has been largely unavailable in the current medical literature. MATERIAL #ENTITYSTARTX00026; By a retrospective review of the literature we aim to compile and compare the focus of EPF and the current knowledge about them. The main aim of this review is to summarize our current knowledge of EPF, including data described almost one century ago; and, to include several unindexed reports, which may have not been available to many current scientists and health care personnel. Foci of EPF have been described in several Central American and South American countries, affecting predominately young people and Amerindians, with an additional female predilection. Although most cases have occurred in Brazil, some cases have been reported in Peru, Paraguay, El Salvador, and Venezuela. Another variant of EPF has been described in El Bagre, Colombia, affecting older men and a few post-menopausal females. Finally, another type of EPF was described in nomadic tribes affecting females of child bearing age in Tunisia, Africa. Our understanding of EPF has been hampered by a lack of government attention to these diseases, especially in some South and Central American countries. Other factors that have made past studies of EPF difficult include 1) that the disease foci are often located in rural areas bordering the rain forest of underdeveloped countries; and 2) military conflicts in some of these areas.

  18. Lyme disease testing in children in an endemic area.

    Science.gov (United States)

    Al-Sharif, Bashar; Hall, Matthew C

    2011-10-01

    The purpose of this study was to determine clinician adherence to recommendations regarding diagnostic testing for Lyme disease (LD). The specific aims were to determine the rate of inappropriate test ordering for a diagnosis of erythema migrans and tack of confirmatory test ordering for positive LD screening tests. Using the data warehouse of Marshfield Clinic Research Foundation's Bioinformatics Research Center, cases were identified from 2002 through 2007. A retrospective chart abstraction was performed using Marshfield Clinic's electronic medical record. The study involved children (testing occurred after a clinical diagnosis of erythema migrans was made. Patients with any symptom in addition to erythema migrans were more likely to have testing (odds ratio (OR) = 3.52, 1.75-7.08). A positive LD screening test was not confirmed 24% of the time. Lack of ordering confirmatory testing was not associated with any clinical factors or site of the evaluation. This study found that some clinicians in an LD-endemic area do not follow guidelines for diagnosing children suspected to have Lyme disease.

  19. Risk Factors for Leprosy Reactions in Three Endemic Countries

    Science.gov (United States)

    Scollard, David M.; Martelli, Celina M. T.; Stefani, Mariane M. A.; Maroja, Maria de Fatima; Villahermosa, Laarni; Pardillo, Fe; Tamang, Krishna B.

    2015-01-01

    The objective of this study was to ascertain risk factors for complications (reactions or neuritis) in leprosy patients at the time of diagnosis in three leprosy-endemic countries. Newly diagnosed patients were enrolled in Brazil, the Philippines, and Nepal, and risk factors for reactions and neuritis were assessed using a case-control approach: “cases” were patients with these complications, and controls were patients without complications. Of 1,972 patients enrolled in this study, 22% had complications before treatment. Type 1 reaction was diagnosed in 13.7% of patients, neuritis alone in 6.9.%, and type 2 reaction in 1.4%. The frequency of these complications was higher in Nepal, in lepromatous patients, in males, and in adults versus children. Reactions and neuritis were seen in patients at diagnosis, before treatment was started. Reactions were seen in adults and children, even in patients with only a single lesion. Neuritis was often present without other signs of reaction. Reactions and neuritis were more likely to occur in lepromatous patients, and were more likely to be seen in adults than in children. PMID:25448239

  20. Number of endemic and native plant species in the Galapagos Archipelago in relation to geographical parameters

    DEFF Research Database (Denmark)

    Willerslev, Eske; Hansen, Anders J.; Nielsen, Kirstine Klitgaard

    2002-01-01

    By simple and multiple regression analyses we investigate updated species numbers of endemic and native vascular plants and seed plants in the Galapagos Archipelago in relation to geographical parameters. We find that the best models to describe species numbers are regression models with log......-transformed species numbers as dependent and log-transformed modified area (i.e. area not covered with barren lava) as an independent variable. This holds both for total species number, for native species number, for endemic species number and for total number of seed plants as well as number of endemic seed plants...

  1. The Caribbean-Colombian cretaceous igneous province: The internal anatomy of an oceanic plateau

    Science.gov (United States)

    Kerr, Andrew C.; Tarney, John; Marriner, Giselle F.; Nivia, Alvaro; Saunders, Andrew D.

    The Late Cretaceous Caribbean—Colombian igneous province is one of the world's best-exposed examples of a plume-derived oceanic plateau. The buoyancy of the plateau (resulting from residual heat and thick crust) kept it from being totally subducted as it moved eastward with the Farallon Plate from its site of generation in the eastern Pacific and encountered a destructive plate margin. In effect, the plateau makes up much of the Caribbean Plate; it is well exposed around its margins, but more so in accreted terranes in western Colombia (including the well-known Gorgona komatiites and Bolívar mafic/ultramafic cumulates). Compositionally, the lavas of the plateau form three groups: (a) basalts, picrites, and komatiites with light-rare-earth-element (LREE)-depleted chondrite-normalised patterns; (b) basalts with LREE-enriched patterns; and (c) basalts with essentially flat REE patterns (the most dominant type) similar to many of the basalts from the Ontong Java Plateau. These three types demonstrate the heterogeneous nature of the mantle plume source region. The picrites and the komatiites seem to lie nearer the base of the plateau than the more homogeneous basalts; thus, the more MgO-rich melts may have been erupted before large magma chambers had a chance to develop. A reconstructed crustal cross section through the plateau consists of dunitic and pyroxenitic cumulates near the base which are overlain by layered olivine-rich gabbros and more isotropic gabbros. The lowermost eruptive sequence comprises compositionally heterogeneous picrites/komatiites overlain by more homogeneous pillow basalts. Spectacular hornblende-plagioclase veins cut the Bolívar assemblage and these may represent local partial melts of the plateau's base as it was thrusted onto the continent. Subduction-related batholiths and extrusive rocks found around the margin of the province are of two distinct ages; one suite represents pre-plateau collision-related volcanism whereas the other suite

  2. The Development in modeling Tibetan Plateau Land/Climate Interaction

    Science.gov (United States)

    Xue, Yongkang; Liu, Ye; li, qian; Maheswor Shrestha, Maheswor; Ma, Hsi-Yen; Cox, Peter; Sun, shufen; Koike, Toshio

    2015-04-01

    Tibetan Plateau (TP) plays an important role in influencing the continental and planetary scale climate, including East Asian and South Asian monsoon, circulation and precipitation over West Pacific and Indian Oceans. The numerical study has identified TP as the area with strongest land/atmosphere interactions over the midlatitude land. The land degradation there has also affected the monsoon precipitation in TP along the monsoon pathway. The water cycle there affects water sources for major Asian river systems, which include the Tarim, Amu Darya, Indus, Ganges, Brahmaputra, Irrawaddy, Salween, Mekong, Yellow, and Yangtze Rivers. Despite the importance of TP land process in the climate system, the TP land surface processes are poorly modeled due to lack of data available for model validation. To better understand, simulate, and project the role of Tibetan Plateau land surface processes, better parameterization of the Tibetan Land surface processes have been developed and evaluated. The recently available field measurement there and satellite observation have greatly helped this development. This paper presents these new developments and preliminary results using the newly developed biophysical/dynamic vegetation model, frozen soil model, and glacier model. In recent CMIP5 simulation, the CMIP5 models with dynamic vegetation model show poor performance in simulating the TP vegetation and climate. To better simulate the TP vegetation condition and its interaction with climate, we have developed biophysical/dynamic vegetation model, the Simplified Simple Biosphere Model version 4/Top-down Representation of Interactive Foliage and Flora Including Dynamics Model (SSiB4/TRIFFID), based on water, carbon, and energy balance. The simulated vegetation variables are updates, driven by carbon assimilation, allocation, and accumulation, as well as competition between plant functional types. The model has been validated with the station data, including those measured over the TP

  3. Aridity changes in the Tibetan Plateau in a warming climate

    International Nuclear Information System (INIS)

    Gao, Yanhong; Li, Xia; Xu, Jianwei; Ruby Leung, L.; Chen, Deliang

    2015-01-01

    Desertification in the Tibetan Plateau (TP) has drawn increasing attention in the recent decades. It has been postulated as a consequence of increasing climate aridity due to the observed warming. This study quantifies the aridity changes in the TP and attributes the changes to different climatic factors. Using the ratio of precipitation to potential evapotranspiration (P/PET) as an aridity index, we used observed meteorological records at 83 stations in the TP to calculate PET using the Penman–Monteith algorithm and the ratio. Spatial and temporal changes of P/PET in 1979–2011 were analyzed. Results show that stations located in the arid and semi-arid northwestern TP are becoming significantly wetter, and half of the stations in the semi-humid eastern TP are becoming drier, though not significantly, in the recent three decades. The aridity change patterns are significantly correlated with the change patterns of precipitation, sunshine duration and diurnal temperature range. Temporal correlations between the annual P/PET ratio and other meteorological variables confirm the significant correlation between aridity and the three variables, with precipitation being the dominant driver of P/PET changes at the interannual time scale. Annual PET are insignificantly but negatively correlated with P/PET in the cold season. In the warm season, however, the correlation between PET and P/PET is significant at the confidence level of 99.9% when the cryosphere near the surface melts. Significant correlation between annual wind speed and aridity occurs in limited locations and months. Consistency in the climatology pattern and linear trends in surface air temperature and precipitation calculated using station data, gridded data, and nearest grid-to-stations for the TP average and across sub-basins indicate the robustness of the trends despite the large spatial heterogeneity in the TP that challenge climate monitoring. (letter)

  4. Plateau subduction, intraslab seismicity, and the Denali (Alaska) volcanic gap

    Science.gov (United States)

    Chuang, Lindsay Yuling; Bostock, Michael; Wech, Aaron; Plourde, Alexandre

    2018-01-01

    Tectonic tremors in Alaska (USA) are associated with subduction of the Yakutat plateau, but their origins are unclear due to lack of depth constraints. We have processed tremor recordings to extract low-frequency earthquakes (LFEs), and generated a set of six LFE waveform templates via iterative network matched filtering and stacking. The timing of impulsive P (compressional) wave and S (shear) wave arrivals on template waveforms places LFEs at 40–58 km depth, near the upper envelope of intraslab seismicity and immediately updip of increased levels of intraslab seismicity. S waves at near-epicentral distances display polarities consistent with shear slip on the plate boundary. We compare characteristics of LFEs, seismicity, and tectonic structures in central Alaska with those in warm subduction zones, and propose a new model for the region’s unusual intraslab seismicity and the enigmatic Denali volcanic gap (i.e., an area of no volcanism where expected). We argue that fluids in the Yakutat plate are confined to its upper crust, and that shallow subduction leads to hydromechanical conditions at the slab interface in central Alaska akin to those in warm subduction zones where similar LFEs and tremor occur. These conditions lead to fluid expulsion at shallow depths, explaining strike-parallel alignment of tremor occurrence with the Denali volcanic gap. Moreover, the lack of double seismic zone and restriction of deep intraslab seismicity to a persistent low-velocity zone are simple consequences of anhydrous conditions prevailing in the lower crust and upper mantle of the Yakutat plate.

  5. MANAGING ENGINEERING ACTIVITIES FOR THE PLATEAU REMEDIATION CONTRACT - HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    KRONVALL CM

    2011-01-14

    In 2008, the primary Hanford clean-up contract transitioned to the CH2MHill Plateau Remediation Company (CHPRC). Prior to transition, Engineering resources assigned to remediation/Decontamination and Decommissioning (D&D) activities were a part of a centralized engineering organization and matrixed to the performing projects. Following transition, these resources were reassigned directly to the performing project, with a loose matrix through a smaller Central Engineering (CE) organization. The smaller (10 FTE) central organization has retained responsibility for the overall technical quality of engineering for the CHPRC, but no longer performs staffing and personnel functions. As the organization has matured, there are lessons learned that can be shared with other organizations going through or contemplating performing a similar change. Benefits that have been seen from the CHPRC CE organization structure include the following: (1) Staff are closely aligned with the 'Project/facility' that they are assigned to support; (2) Engineering priorities are managed to be consistent with the 'Project/facility' priorities; (3) Individual Engineering managers are accountable for identifying staffing needs and the filling of staffing positions; (4) Budget priorities are managed within the local organization structure; (5) Rather than being considered a 'functional' organization, engineering is considered a part of a line, direct funded organization; (6) The central engineering organization is able to provide 'overview' activities and maintain independence from the engineering organizations in the field; and (7) The central engineering organization is able to maintain a stable of specialized experts that are able to provide independent reviews of field projects and day-to-day activities.

  6. MANAGING ENGINEERING ACTIVITIES FOR THE PLATEAU REMEDIATION CONTRACT - HANFORD

    International Nuclear Information System (INIS)

    Kronvall, C.M.

    2011-01-01

    In 2008, the primary Hanford clean-up contract transitioned to the CH2MHill Plateau Remediation Company (CHPRC). Prior to transition, Engineering resources assigned to remediation/Decontamination and Decommissioning (D and D) activities were a part of a centralized engineering organization and matrixed to the performing projects. Following transition, these resources were reassigned directly to the performing project, with a loose matrix through a smaller Central Engineering (CE) organization. The smaller (10 FTE) central organization has retained responsibility for the overall technical quality of engineering for the CHPRC, but no longer performs staffing and personnel functions. As the organization has matured, there are lessons learned that can be shared with other organizations going through or contemplating performing a similar change. Benefits that have been seen from the CHPRC CE organization structure include the following: (1) Staff are closely aligned with the 'Project/facility' that they are assigned to support; (2) Engineering priorities are managed to be consistent with the 'Project/facility' priorities; (3) Individual Engineering managers are accountable for identifying staffing needs and the filling of staffing positions; (4) Budget priorities are managed within the local organization structure; (5) Rather than being considered a 'functional' organization, engineering is considered a part of a line, direct funded organization; (6) The central engineering organization is able to provide 'overview' activities and maintain independence from the engineering organizations in the field; and (7) The central engineering organization is able to maintain a stable of specialized experts that are able to provide independent reviews of field projects and day-to-day activities.

  7. Arbovirological survey in Silica plateau area, Roznava District, Czechoslovakia.

    Science.gov (United States)

    Hubálek, Z; Cerný, V; Mittermayer, T; Kilík, J; Halouzka, J; Juricová, Z; Kuhn, I; Bárdos, V

    1986-01-01

    The serosurveys conducted in the Silica plateau area of the Slovak karst region revealed the presence of specific neutralizing antibody against tick-borne encephalitis (TBE) virus in 18% of local inhabitants (33 examined, mostly goats and sheep farmers), 54% of goats (26 examined), 18% of sheep (120 examined) and 13% of cattle (60 examined), against Lipovník (LIP) virus in 30% of inhabitants, 88% of goats, 55% of sheep and 45% of cattle, and against Bhanja (BHA) virus in 27% of inhabitants, 46% of goats, 29% of sheep and 23% of cattle. The results of hemagglutination-inhibition tests with TBE and BHA antigens were analogous. A detailed analysis of these serologic data points to a recent enhancement of the circulation of LIP and BHA viruses and to a very low TBE virus activity in this natural focus of arboviral infections. The immunological surveys of the 32 former "Roznava disease" patients, conducted 25 years after an extensive epidemic of a TBE virus infection that originated in Roznava in 1951, revealed the presence of neutralizing (and also hemagglutination-inhibiting) antibodies against TBE virus in as many as 78% of cases. Antibodies against LIP and BHA viruses were also detectable in the sera of 16% and 9%, respectively, of these individuals. Populations of the ectoparasites examined for the presence of arbovirus comprised 231 Ixodes ricinus, 806 Dermacentor marginatus and 204 Haemaphysalis punctata ticks and 117 specimens of the louse-flies Melophagus ovinus. Two strains of arbivirus that were antigenically related to Lipovník and Tribec viruses belonging to a group of Kemerovo viruses were isolated from male and female I. ricinus ticks collected from cattle.

  8. Three-dimensional Crustal Structure beneath the Tibetan Plateau Revealed by Multi-scale Gravity Analysis

    Science.gov (United States)

    Xu, C.; Luo, Z.; Sun, R.; Li, Q.

    2017-12-01

    The Tibetan Plateau, the largest and highest plateau on Earth, was uplifted, shorten and thicken by the collision and continuous convergence of the Indian and Eurasian plates since 50 million years ago, the Eocene epoch. Fine three-dimensional crustal structure of the Tibetan Plateau is helpful in understanding the tectonic development. At present, the ordinary method used for revealing crustal structure is seismic method, which is inhibited by poor seismic station coverage, especially in the central and western plateau primarily due to the rugged terrain. Fortunately, with the implementation of satellite gravity missions, gravity field models have demonstrated unprecedented global-scale accuracy and spatial resolution, which can subsequently be employed to study the crustal structure of the entire Tibetan Plateau. This study inverts three-dimensional crustal density and Moho topography of the Tibetan Plateau from gravity data using multi-scale gravity analysis. The inverted results are in agreement with those provided by the previous works. Besides, they can reveal rich tectonic development of the Tibetan Plateau: (1) The low-density channel flow can be observed from the inverted crustal density; (2) The Moho depth in the west is deeper than that in the east, and the deepest Moho, which is approximately 77 km, is located beneath the western Qiangtang Block; (3) The Moho fold, the directions of which are in agreement with the results of surface movement velocities estimated from Global Positioning System, exists clearly on the Moho topography.This study is supported by the National Natural Science Foundation of China (Grant No. 41504015), the China Postdoctoral Science Foundation (Grant No. 2015M572146), and the Surveying and Mapping Basic Research Programme of the National Administration of Surveying, Mapping and Geoinformation (Grant No. 15-01-08).

  9. Surface ozone at Nam Co in the inland Tibetan Plateau: variation, synthesis comparison and regional representativeness

    Science.gov (United States)

    Yin, Xiufeng; Kang, Shichang; de Foy, Benjamin; Cong, Zhiyuan; Luo, Jiali; Zhang, Lang; Ma, Yaoming; Zhang, Guoshuai; Rupakheti, Dipesh; Zhang, Qianggong

    2017-09-01

    Ozone is an important pollutant and greenhouse gas, and tropospheric ozone variations are generally associated with both natural and anthropogenic processes. As one of the most pristine and inaccessible regions in the world, the Tibetan Plateau has been considered as an ideal region for studying processes of the background atmosphere. Due to the vast area of the Tibetan Plateau, sites in the southern, northern and central regions exhibit different patterns of variation in surface ozone. Here, we present continuous measurements of surface ozone mixing ratios at Nam Co Station over a period of ˜ 5 years (January 2011 to October 2015), which is a background site in the inland Tibetan Plateau. An average surface ozone mixing ratio of 47.6 ± 11.6 ppb (mean ± standard deviation) was recorded, and a large annual cycle was observed with maximum ozone mixing ratios in the spring and minimum ratios during the winter. The diurnal cycle is characterized by a minimum in the early morning and a maximum in the late afternoon. Nam Co Station represents a background region where surface ozone receives negligible local anthropogenic emissions inputs, and the anthropogenic contribution from South Asia in spring and China in summer may affect Nam Co Station occasionally. Surface ozone at Nam Co Station is mainly dominated by natural processes involving photochemical reactions, vertical mixing and downward transport of stratospheric air mass. Model results indicate that the study site is affected differently by the surrounding areas in different seasons: air masses from the southern Tibetan Plateau contribute to the high ozone levels in the spring, and enhanced ozone levels in the summer are associated with air masses from the northern Tibetan Plateau. By comparing measurements at Nam Co Station with those from other sites on the Tibetan Plateau, we aim to expand the understanding of ozone cycles and transport processes over the Tibetan Plateau. This work may provide a

  10. Estimating the Global Burden of Endemic Canine Rabies

    Science.gov (United States)

    Hampson, Katie; Coudeville, Laurent; Lembo, Tiziana; Sambo, Maganga; Kieffer, Alexia; Attlan, Michaël; Barrat, Jacques; Blanton, Jesse D.; Briggs, Deborah J.; Cleaveland, Sarah; Costa, Peter; Freuling, Conrad M.; Hiby, Elly; Knopf, Lea; Leanes, Fernando; Meslin, François-Xavier; Metlin, Artem; Miranda, Mary Elizabeth; Müller, Thomas; Nel, Louis H.; Recuenco, Sergio; Rupprecht, Charles E.; Schumacher, Carolin; Taylor, Louise; Vigilato, Marco Antonio Natal; Zinsstag, Jakob; Dushoff, Jonathan

    2015-01-01

    Background Rabies is a notoriously underreported and neglected disease of low-income countries. This study aims to estimate the public health and economic burden of rabies circulating in domestic dog populations, globally and on a country-by-country basis, allowing an objective assessment of how much this preventable disease costs endemic countries. Methodology/Principal Findings We established relationships between rabies mortality and rabies prevention and control measures, which we incorporated into a model framework. We used data derived from extensive literature searches and questionnaires on disease incidence, control interventions and preventative measures within this framework to estimate the disease burden. The burden of rabies impacts on public health sector budgets, local communities and livestock economies, with the highest risk of rabies in the poorest regions of the world. This study estimates that globally canine rabies causes approximately 59,000 (95% Confidence Intervals: 25-159,000) human deaths, over 3.7 million (95% CIs: 1.6-10.4 million) disability-adjusted life years (DALYs) and 8.6 billion USD (95% CIs: 2.9-21.5 billion) economic losses annually. The largest component of the economic burden is due to premature death (55%), followed by direct costs of post-exposure prophylaxis (PEP, 20%) and lost income whilst seeking PEP (15.5%), with only limited costs to the veterinary sector due to dog vaccination (1.5%), and additional costs to communities from livestock losses (6%). Conclusions/Significance This study demonstrates that investment in dog vaccination, the single most effective way of reducing the disease burden, has been inadequate and that the availability and affordability of PEP needs improving. Collaborative investments by medical and veterinary sectors could dramatically reduce the current large, and unnecessary, burden of rabies on affected communities. Improved surveillance is needed to reduce uncertainty in burden estimates and to

  11. Malaria situation in an endemic area, southeastern iran.

    Directory of Open Access Journals (Sweden)

    Sajjad Fekri

    2014-06-01

    Full Text Available Malaria is an endemic infectious disease in southeastern parts of Iran. Despite years of efforts and intervention programs against malaria, transmission still occurs in Jask County.The epidemiological perspective of malaria in Jask County was conducted by gathering data from Jask County health center, during 2006-2010. A knowledge, attitude and practice study was also carried out. Data analysis was conducted using SPSS ver. 11.5.A total of 2875 malaria cases were recorded, with highest and lowest numbers in 2007 and 2010, respectively. The number of cases had a decreasing trend from 1022 cases in 2006 to 114 cases in 2010. The main causative parasitic agent was Plasmodium vivax. Blood examination rate and slide positive rate were also decreased from 39.5% and 4.3% in 2006 to 15.6% and 1.4% in 2010, respectively. Most of people interviewed in the KAP study had a good knowledge about malaria transmission and symptoms but their use of the bed net for prevention was low (35%.Malaria incidence had significant reduction during the study years. The main reason for this may be due to changing environmental condition for Anopheline breeding and survival because of drought. Another reason may be integration of vector management by using long lasting insecticide treated bed nets, active case detection and treatment by implementation of mobile teams and increasing in financial sources of malaria control program. Knowledge, attitude and practice of people were good in malaria control and prevention, but needs to do more activities for health education and awareness.

  12. Toll-like receptor polymorphisms in malaria-endemic populations

    Directory of Open Access Journals (Sweden)

    Zimmerman Peter A

    2009-03-01

    Full Text Available Abstract Background Toll-like receptors (TLR and related downstream signaling pathways of innate immunity have been implicated in the pathogenesis of Plasmodium falciparum malaria. Because of their potential role in malaria pathogenesis, polymorphisms in these genes may be under selective pressure in populations where this infectious disease is endemic. Methods A post-PCR Ligation Detection Reaction-Fluorescent Microsphere Assay (LDR-FMA was developed to determine the frequencies of TLR2, TLR4, TLR9, MyD88-Adaptor Like Protein (MAL single nucleotide polymorphisms (SNPs, and TLR2 length polymorphisms in 170 residents of two regions of Kenya where malaria transmission is stable and high (holoendemic or episodic and low, 346 residents of a malaria holoendemic region of Papua New Guinea, and 261 residents of North America of self-identified ethnicity. Results The difference in historical malaria exposure between the two Kenyan sites has significantly increased the frequency of malaria protective alleles glucose-6-phoshpate dehydrogenase (G6PD and Hemoglobin S (HbS in the holoendemic site compared to the episodic transmission site. However, this study detected no such difference in the TLR2, TLR4, TLR9, and MAL allele frequencies between the two study sites. All polymorphisms were in Hardy Weinberg Equilibrium in the Kenyan and Papua New Guinean populations. TLR9 SNPs and length polymorphisms within the TLR2 5' untranslated region were the only mutant alleles present at a frequency greater than 10% in all populations. Conclusion Similar frequencies of TLR2, TLR4, TLR9, and MAL genetic polymorphisms in populations with different histories of malaria exposure suggest that these innate immune pathways have not been under strong selective pressure by malaria. Genotype frequencies are consistent with Hardy-Weinberg Equilibrium and the Neutral Theory, suggesting that genetic drift has influenced allele frequencies to a greater extent than selective

  13. Species distribution modelling for conservation of an endangered endemic orchid.

    Science.gov (United States)

    Wang, Hsiao-Hsuan; Wonkka, Carissa L; Treglia, Michael L; Grant, William E; Smeins, Fred E; Rogers, William E

    2015-04-21

    Concerns regarding the long-term viability of threatened and endangered plant species are increasingly warranted given the potential impacts of climate change and habitat fragmentation on unstable and isolated populations. Orchidaceae is the largest and most diverse family of flowering plants, but it is currently facing unprecedented risks of extinction. Despite substantial conservation emphasis on rare orchids, populations continue to decline. Spiranthes parksii (Navasota ladies' tresses) is a federally and state-listed endangered terrestrial orchid endemic to central Texas. Hence, we aimed to identify potential factors influencing the distribution of the species, quantify the relative importance of each factor and determine suitable habitat for future surveys and targeted conservation efforts. We analysed several geo-referenced variables describing climatic conditions and landscape features to identify potential factors influencing the likelihood of occurrence of S. parksii using boosted regression trees. Our model classified 97 % of the cells correctly with regard to species presence and absence, and indicated that probability of existence was correlated with climatic conditions and landscape features. The most influential variables were mean annual precipitation, mean elevation, mean annual minimum temperature and mean annual maximum temperature. The most likely suitable range for S. parksii was the eastern portions of Leon and Madison Counties, the southern portion of Brazos County, a portion of northern Grimes County and along the borders between Burleson and Washington Counties. Our model can assist in the development of an integrated conservation strategy through: (i) focussing future survey and research efforts on areas with a high likelihood of occurrence, (ii) aiding in selection of areas for conservation and restoration and (iii) framing future research questions including those necessary for predicting responses to climate change. Our model could also

  14. Estimating the global burden of endemic canine rabies.

    Directory of Open Access Journals (Sweden)

    Katie Hampson

    2015-04-01

    Full Text Available Rabies is a notoriously underreported and neglected disease of low-income countries. This study aims to estimate the public health and economic burden of rabies circulating in domestic dog populations, globally and on a country-by-country basis, allowing an objective assessment of how much this preventable disease costs endemic countries.We established relationships between rabies mortality and rabies prevention and control measures, which we incorporated into a model framework. We used data derived from extensive literature searches and questionnaires on disease incidence, control interventions and preventative measures within this framework to estimate the disease burden. The burden of rabies impacts on public health sector budgets, local communities and livestock economies, with the highest risk of rabies in the poorest regions of the world. This study estimates that globally canine rabies causes approximately 59,000 (95% Confidence Intervals: 25-159,000 human deaths, over 3.7 million (95% CIs: 1.6-10.4 million disability-adjusted life years (DALYs and 8.6 billion USD (95% CIs: 2.9-21.5 billion economic losses annually. The largest component of the economic burden is due to premature death (55%, followed by direct costs of post-exposure prophylaxis (PEP, 20% and lost income whilst seeking PEP (15.5%, with only limited costs to the veterinary sector due to dog vaccination (1.5%, and additional costs to communities from livestock losses (6%.This study demonstrates that investment in dog vaccination, the single most effective way of reducing the disease burden, has been inadequate and that the availability and affordability of PEP needs improving. Collaborative investments by medical and veterinary sectors could dramatically reduce the current large, and unnecessary, burden of rabies on affected communities. Improved surveillance is needed to reduce uncertainty in burden estimates and to monitor the impacts of control efforts.

  15. Phylogeny and evolutionary history of Leymus (Triticeae; Poaceae based on a single-copy nuclear gene encoding plastid acetyl-CoA carboxylase

    Directory of Open Access Journals (Sweden)

    Ding Cun-Bang

    2009-10-01

    Full Text Available Abstract Background Single- and low- copy genes are less likely subject to concerted evolution, thus making themselves ideal tools for studying the origin and evolution of polyploid taxa. Leymus is a polyploid genus with a diverse array of morphology, ecology and distribution in Triticeae. The genomic constitution of Leymus was assigned as NsXm, where Ns was presumed to be originated from Psathyrostachys, while Xm represented a genome of unknown origin. In addition, little is known about the evolutionary history of Leymus. Here, we investigate the phylogenetic relationship, genome donor, and evolutionary history of Leymus based on a single-copy nuclear Acc1 gene. Results Two homoeologues of the Acc1 gene were isolated from nearly all the sampled Leymus species using allele-specific primer and were analyzed with those from 35 diploid taxa representing 18 basic genomes in Triticeae. Sequence diversity patterns and genealogical analysis suggested that (1 Leymus is closely related to Psathyrostachys, Agropyron, and Eremopyrum; (2 Psathyrostachys juncea is an ancestral Ns-genome donor of Leymus species; (3 the Xm genome in Leymus may be originated from an ancestral lineage of Agropyron and Eremopyrum triticeum; (4 the Acc1 sequences of Leymus species from the Qinghai-Tibetan plateau are evolutionarily distinct; (5 North America Leymus species might originate from colonization via the Bering land bridge; (6 Leymus originated about 11-12MYA in Eurasia, and adaptive radiation might have occurred in Leymus during the period of 3.7-4.3 MYA and 1.7-2.1 MYA. Conclusion Leymus species have allopolyploid origin. It is hypothesized that the adaptive radiation of Leymus species might have been triggered by the recent upliftings of the Qinghai-Tibetan plateau and subsequent climatic oscillations. Adaptive radiation may have promoted the rapid speciation, as well as the fixation of unique morphological characters in Leymus. Our results shed new light on our

  16. Genetic analysis of Asian measles virus strains--new endemic genotype in Nepal.

    Science.gov (United States)

    Truong, A T; Mulders, M N; Gautam, D C; Ammerlaan, W; de Swart, R L; King, C C; Osterhaus, A D; Muller, C P

    2001-07-01

    In many parts of Asia measles virus (MV) continues to be endemic. However, little is known about the genetic characteristics of viruses circulating on this continent. This study reports the molecular epidemiological analysis based on the entire nucleocapsid (N) and hemagglutinin (H) genes of the first isolates from Nepal and Taiwan, as well as of recent MV strains from India, Indonesia, and China. Four isolates collected in various regions in Nepal during 1999 belonged to a new genotype, tentatively called D8. Another Nepalese isolate and one from India belonged to genotype D4. The diversity of the Nepalese strains indicated that measles continues to be endemic in this country. The isolate from Taiwan grouped with D3 viruses and one Chinese strain isolated in The Netherlands was assigned to the previously described clade H, known to be endemic in Mainland China. Molecular characterization emerges as an important tool for monitoring virus endemicity and vaccination efforts.

  17. The phylogenetic relationships of endemic Australasian trichostrongylin families (Nematoda: Strongylida) parasitic in marsupials and monotremes.

    Science.gov (United States)

    Chilton, Neil B; Huby-Chilton, Florence; Koehler, Anson V; Gasser, Robin B; Beveridge, Ian

    2015-10-01

    The phylogenetic relationships of the endemic (or largely endemic) Australasian trichostrongylin nematode families Herpetostrongylidae, Mackerrastrongylidae and Nicollinidae as well as endemic trichostrongylin nematodes currently placed in the families Trichostrongylidae and Molineidae were examined using the complete large subunit (28S) ribosomal RNA gene. The Herpetostrongylinae proved to be monophyletic. However, representatives of the Nicollinidae nested with the Herpetostrongylinae. The Mackerrastrongylidae was also a monophyletic group and included Peramelistrongylus, currently classified within the Trichostrongylidae. The Globocephaloidinae, currently considered to be a subfamily of the Herpetostrongylidae, was excluded from the family in the current analysis. Ollulanus and Libyostrongylus, included for the first time in a molecular phylogenetic analysis, were placed within the Trichostrongylidae. This study provided strong support for the Herpetostrongylidae (including within it the Nicollinidae, but excluding the Globocephaloidinae) and the Mackerrastrongylidae as monophyletic assemblages. Additional studies are required to resolve the relationships of the remaining endemic Australasian trichostrongylin genera.

  18. Egg predators of an endemic Italian salamander, Salamandrina perspicillata (Savi, 1821

    Directory of Open Access Journals (Sweden)

    Antonio Romano

    2008-05-01

    Full Text Available We report new aquatic predators feeding on Northern spectacled salamander eggs, Salamandrina perspicillata, an endemic Italian species. Eggs were preyed upon by the leech, Trocheta bykowskii, and the trichopteran larvae of Potamophylax cingulatus and Halesus appenninus.

  19. Human-induced hybridization among congeneric endemic plants on Tenerife, Canary Islands

    NARCIS (Netherlands)

    van Hengstum, T.; Lachmuth, S.; Oostermeijer, J.G.B.; den Nijs, J.C.M.; Meirmans, P.G.; van Tienderen, P.H.

    2012-01-01

    Endemic genera on oceanic islands often evolved striking morphological and ecological differences among species, with weak postzygotic reproductive isolation. Human activities can lead to increased connectivity and can thereby promote secondary contact and hybridization between previously isolated

  20. Relationship between weathered coal deposits and the etiology of Balkan endemic nephropathy

    International Nuclear Information System (INIS)

    Feder, G.L.; Radovanovic, Z.; Finkelman, R.B.

    1991-01-01

    Field studies in epidemiology and environmental geochemistry in areas in Yugoslavia containing villages with a high incidence of Balkan endemic nephropathy (BEN), indicate a possible relationship between the presence of low-rank coal deposits and the etiology of BEN. Preliminary results from qualitative chemical analyses of drinking water from shallow farm wells indicate the presence of soluble polar aromatic and polynuclear aromatic hydrocarbons. These compounds may be derived from weathering of low-rank coals occurring in the vicinity of the endemic villages. All of the endemic villages are in alluvial valleys of tributaries to the Danube River. All except one of the clusters of endemic villages are located in the vicinity of known Pliocene age coals. Detailed sampling of the drinking waters and the nearby coals are being undertaken to identify a possible etiologic factor

  1. Co-endemicity of Cysticercosis and Schistosomiasis in Africa - how many people are at risk?

    DEFF Research Database (Denmark)

    Saarnak, Christopher; Braae, Uffe Christian; Magnussen, Pascal

    The World Health Organisation (WHO) is aiming for elimination of schistosomiasis by 2020 through mass drug administration (MDA). However, the drug used for this, praziquantel, has been reported to cause dramatic side effects, even death, among people suffering from neurocysticercosis (NCC). Both...... countries were identified. The co-endemicity dataset was then combined with modelled data on population density for 2015 derived from the WorldPop database (http://www.worldpop.org). We used the open source GIS software QGIS and GRASS to overlay the two datasets and identified the number of people living...... in co-endemic districts. Over 135 million people live in co-endemic areas. Of these, almost 44 million live in high prevalence areas for schistosomiasis where WHO recommend MDA for the entire population. In co-endemic areas resources need to be allocated for evaluating the extent of adverse effects...

  2. Identification of seventeen microsatellite loci for conservation genetic studies of the endemic wrasse Coris bulbifrons

    KAUST Repository

    Van Der Meer, Martin H.; Gardner, Mike; Berumen, Michael L.; Hobbs, Jean Paul Adrian; Van Herwerden, Lynne Van

    2012-01-01

    Coral reefs around the world are in decline, in part due to various anthropogenic factors, including fishing pressure. Coris bulbifrons is a large wrasse endemic to only four oceanic locations off Australia's east coast: Middleton Reef, Elizabeth

  3. Among-species differences in pollen quality and quantity limitation: implications for endemics in biodiverse hotspots.

    Science.gov (United States)

    Alonso, Conchita; Navarro-Fernández, Carmen M; Arceo-Gómez, Gerardo; Meindl, George A; Parra-Tabla, Víctor; Ashman, Tia-Lynn

    2013-11-01

    Insufficient pollination is a function of quantity and quality of pollen receipt, and the relative contribution of each to pollen limitation may vary with intrinsic plant traits and extrinsic ecological properties. Community-level studies are essential to evaluate variation across species in quality limitation under common ecological conditions. This study examined whether endemic species are more limited by pollen quantity or quality than non-endemic co-flowering species in three endemic-rich plant communities located in biodiversity hotspots of different continents (Andalusia, California and Yucatan). Natural variations in pollen receipt and pollen tube formation were analysed for 20 insect-pollinated plants. Endemic and non-endemic species that co-flowered were paired in order to estimate and compare the quantity and quality components of pre-zygotic pollination success, obtained through piecewise regression analysis of the relationship between pollen grains and pollen tubes of naturally pollinated wilted flowers. Pollen tubes did not frequently exceed the number of ovules per flower. Only the combination of abundant and good quality pollen and a low number of ovules per flower conferred relief from pre-zygotic pollen limitation in the three stochastic pollination environments studied. Quality of pollen receipt was found to be as variable as quantity among study species. The relative pollination success of endemic and non-endemic species, and its quantity and quality components, was community dependent. Assessing both quality and quantity of pollen receipt is key to determining the ovule fertilization potential of both endemic and widespread plants in biodiverse hotspot regions. Large natural variation among flowers of the same species in the two components and pollen tube formation deserves further analysis in order to estimate the environmental, phenotypic and intraindividual sources of variation that may affect how plants evolve to overcome this limitation in

  4. A review of contemporary patterns of endemism for shallow water reef fauna in the Red Sea

    KAUST Repository

    DiBattista, Joseph; Roberts, May B.; Bouwmeester, Jessica; Bowen, Brian W.; Coker, Darren James; Lozano-Corté s, Diego; Howard Choat, J.; Gaither, Michelle R.; Hobbs, Jean-Paul A.; Khalil, Maha T.; Kochzius, Marc; Myers, Robert F.; Paulay, Gustav; Robitzch, Vanessa S.N.; Saenz Agudelo, Pablo; Salas, Eva; Sinclair-Taylor, Tane; Toonen, Robert J.; Westneat, Mark W.; Williams, Suzanne T.; Berumen, Michael L.

    2015-01-01

    The Red Sea biota appears resilient to major environmental fluctuations and is characterized by high rates of endemism with variable degrees of incursion into the Gulf of Aden. The nearby Omani and Arabian Gulfs also have variable environments and high levels of endemism, but these are not consistently distinct across taxa. The presence of physical barriers does not appear to explain species distributions, which are more likely determined by ecological plasticity and genetic diversity.

  5. Intraoperative study on anthropometry and gender differences of the proximal tibial plateau at the arthroplasty resection surface.

    Science.gov (United States)

    Yang, Bo; Yu, Jiakuo; Gong, Xi; Chen, Lianxu; Wang, Yongjian; Wang, Jian; Wang, Haijun; Zhang, Jiying

    2014-01-01

    The tibial plateau is asymmetric with a larger medial plateau. We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau. Tibial plateau also showed other shapes. The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences. A total of 822 knees (164 males, 658 females) from the Chinese population were measured intraoperatively for medial anteroposterior (MAP) and lateral anteroposterior (LAP) dimensions of the resected proximal tibial surface. The difference of MAP and LAP (DML) was also calculated as MAP minus LAP. We then classified the data into three groups based on the DML (2 mm) to analyze the morphology of the proximal tibia and its distribution between male and female. The shape of proximal tibial plateau was of three types: larger medial plateau type, symmetric type, and larger lateral plateau type. There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau (P 2 mm and 120 of 822 (14.6%) tibia having a DMLDMLs to better match the different anthropometry of the resected tibial surface.

  6. China's endemic vertebrates sheltering under the protective umbrella of the giant panda.

    Science.gov (United States)

    Li, Binbin V; Pimm, Stuart L

    2016-04-01

    The giant panda attracts disproportionate conservation resources. How well does this emphasis protect other endemic species? Detailed data on geographical ranges are not available for plants or invertebrates, so we restrict our analyses to 3 vertebrate taxa: birds, mammals, and amphibians. There are gaps in their protection, and we recommend practical actions to fill them. We identified patterns of species richness, then identified which species are endemic to China, and then which, like the panda, live in forests. After refining each species' range by its known elevational range and remaining forest habitats as determined from remote sensing, we identified the top 5% richest areas as the centers of endemism. Southern mountains, especially the eastern Hengduan Mountains, were centers for all 3 taxa. Over 96% of the panda habitat overlapped the endemic centers. Thus, investing in almost any panda habitat will benefit many other endemics. Existing panda national nature reserves cover all but one of the endemic species that overlap with the panda's distribution. Of particular interest are 14 mammal, 20 bird, and 82 amphibian species that are inadequately protected. Most of these species the International Union for Conservation of Nature currently deems threatened. But 7 mammal, 3 bird, and 20 amphibian species are currently nonthreatened, yet their geographical ranges are pandas are absent and where there are no national nature reserves. The others concentrate in Yunnan, Nan Mountains, and Hainan. Here, 10 prefectures might establish new protected areas or upgrade local nature reserves to national status. © 2015 Society for Conservation Biology.

  7. Diversification of an emerging pathogen in a biodiversity hotspot: Leptospira in endemic small mammals of Madagascar.

    Science.gov (United States)

    Dietrich, Muriel; Wilkinson, David A; Soarimalala, Voahangy; Goodman, Steven M; Dellagi, Koussay; Tortosa, Pablo

    2014-06-01

    Biodiversity hotspots and associated endemism are ideal systems for the study of parasite diversity within host communities. Here, we investigated the ecological and evolutionary forces acting on the diversification of an emerging bacterial pathogen, Leptospira spp., in communities of endemic Malagasy small mammals. We determined the infection rate with pathogenic Leptospira in 20 species of sympatric rodents (subfamily Nesomyinae) and tenrecids (family Tenrecidae) at two eastern humid forest localities. A multilocus genotyping analysis allowed the characterization of bacterial diversity within small mammals and gave insights into their genetic relationships with Leptospira infecting endemic Malagasy bats (family Miniopteridae and Vespertilionidae). We report for the first time the presence of pathogenic Leptospira in Malagasy endemic small mammals, with an overall prevalence of 13%. In addition, these hosts harbour species of Leptospira (L. kirschneri, L. borgpetersenii and L. borgpetersenii group B) which are different from those reported in introduced rats (L. interrogans) on Madagascar. The diversification of Leptospira on Madagascar can be traced millions of years into evolutionary history, resulting in the divergence of endemic lineages and strong host specificity. These observations are discussed in relation to the relative roles of endemic vs. introduced mammal species in the evolution and epidemiology of Leptospira on Madagascar, specifically how biodiversity and biogeographical processes can shape community ecology of an emerging pathogen and lead to its diversification within native animal communities. © 2014 John Wiley & Sons Ltd.

  8. Nitrogen species in drinking water indicate potential exposure pathway for Balkan Endemic Nephropathy

    International Nuclear Information System (INIS)

    Niagolova, Nedialka; McElmurry, Shawn P.; Voice, Thomas C.; Long, David T.; Petropoulos, Evangelos A.; Havezov, Ivan; Chou, Karen; Ganev, Varban

    2005-01-01

    This study explored two hypotheses relating elevated concentrations of nitrogen species in drinking water and the disease Balkan Endemic Nephropathy (BEN). Drinking water samples were collected from a variety of water supplies in both endemic and non-endemic villages in the Vratza and Montana districts of Bulgaria. The majority of well water samples exceeded US drinking water standards for nitrate + nitrite. No statistically significant difference was observed for any of the nitrogen species between villages classified as endemic and non-endemic. Other constituents (sodium, potassium and chloride) known to be indicators of anthropogenic pollution were also found at elevated concentrations and all followed the order wells > springs > taps. This ordering coincides with the proximity of human influences to the water sources. Our results clearly establish an exposure pathway between anthropogenic activity and drinking water supplies, suggesting that the causative agent for BEN could result from surface contamination. - Water in villages affected and unaffected by Balkan Endemic Nephropathy had no significant differences in nitrogen compounds

  9. Measuring elimination of podoconiosis, endemicity classifications, case definition and targets: an international Delphi exercise.

    Science.gov (United States)

    Deribe, Kebede; Wanji, Samuel; Shafi, Oumer; Muheki Tukahebwa, Edridah; Umulisa, Irenee; Davey, Gail

    2015-09-01

    Podoconiosis is one of the major causes of lymphoedema in the tropics. Nonetheless, currently there are no endemicity classifications or elimination targets to monitor the effects of interventions. This study aimed at establishing case definitions and indicators that can be used to assess endemicity, elimination and clinical outcomes of podoconiosis. This paper describes the result of a Delphi technique used among 28 experts. A questionnaire outlining possible case definitions, endemicity classifications, elimination targets and clinical outcomes was developed. The questionnaire was distributed to experts working on podoconiosis and other neglected tropical diseases in two rounds. The experts rated the importance of case definitions, endemic classifications, elimination targets and the clinical outcome measures. Median and mode were used to describe the central tendency of expert responses. The coefficient of variation was used to describe the dispersals of expert responses. Consensus on definitions and indicators for assessing endemicity, elimination and clinical outcomes of podoconiosis directed at policy makers and health workers was achieved following the two rounds of Delphi approach among the experts. Based on the two Delphi rounds we discuss potential indicators and endemicity classification of this disabling disease, and the ongoing challenges to its elimination in countries with the highest prevalence. Consensus will help to increase effectiveness of podoconiosis elimination efforts and ensure comparability of outcome data. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

  10. Reconsidering contact precautions for endemic methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus.

    Science.gov (United States)

    Morgan, Daniel J; Murthy, Rekha; Munoz-Price, L Silvia; Barnden, Marsha; Camins, Bernard C; Johnston, B Lynn; Rubin, Zachary; Sullivan, Kaede V; Shane, Andi L; Dellinger, E Patchen; Rupp, Mark E; Bearman, Gonzalo

    2015-10-01

    Whether contact precautions (CP) are required to control the endemic transmission of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) in acute care hospitals is controversial in light of improvements in hand hygiene, MRSA decolonization, environmental cleaning and disinfection, fomite elimination, and chlorhexidine bathing. To provide a framework for decision making around use of CP for endemic MRSA and VRE based on a summary of evidence related to use of CP, including impact on patients and patient care processes, and current practices in use of CP for MRSA and VRE in US hospitals. A literature review, a survey of Society for Healthcare Epidemiology of America Research Network members on use of CP, and a detailed examination of the experience of a convenience sample of hospitals not using CP for MRSA or VRE. Hospital epidemiologists and infection prevention experts. No high quality data support or reject use of CP for endemic MRSA or VRE. Our survey found more than 90% of responding hospitals currently use CP for MRSA and VRE, but approximately 60% are interested in using CP in a different manner. More than 30 US hospitals do not use CP for control of endemic MRSA or VRE. Higher quality research on the benefits and harms of CP in the control of endemic MRSA and VRE is needed. Until more definitive data are available, the use of CP for endemic MRSA or VRE in acute care hospitals should be guided by local needs and resources.

  11. Shared and unique signals of high-altitude adaptation in geographically distinct Tibetan populations.

    Directory of Open Access Journals (Sweden)

    Tana Wuren

    Full Text Available Recent studies have used a variety of analytical methods to identify genes targeted by selection in high-altitude populations located throughout the Tibetan Plateau. Despite differences in analytic strategies and sample location, hypoxia-related genes, including EPAS1 and EGLN1, were identified in multiple studies. By applying the same analytic methods to genome-wide SNP information used in our previous study of a Tibetan population (n = 31 from the township of Maduo, located in the northeastern corner of the Qinghai-Tibetan Plateau (4200 m, we have identified common targets of natural selection in a second geographically and linguistically distinct Tibetan population (n = 46 in the Tuo Tuo River township (4500 m. Our analyses provide evidence for natural selection based on iHS and XP-EHH signals in both populations at the p<0.02 significance level for EPAS1, EGLN1, HMOX2, and CYP17A1 and for PKLR, HFE, and HBB and HBG2, which have also been reported in other studies. We highlight differences (i.e., stratification and admixture in the two distinct Tibetan groups examined here and report selection candidate genes common to both groups. These findings should be considered in the prioritization of selection candidate genes in future genetic studies in Tibet.

  12. [Correlation between morphogical factor of lateral plateau fracture and meniscus injury].

    Science.gov (United States)

    Bai, L; Zhou, W; Zhang, W T; Huang, W; You, T; Chen, P; Zhang, H L

    2016-04-18

    To analyze morphological character of lateral tibial plateau fracture fragment, and its correlation to the presence of a meniscus injury in tibial plateau fractures. A total of 79 consecutive patients of the simple lateral tibial plateau fractures from July 2011 to July 2015 were included in this study, with 65 males and 14 females with an average age of (34.3±7.2) years and 22-61 years. According to Schatzker classification, 21 cases were of Type I, 41 cases Type II, and 17 cases Type III. The characteristics of lateral tibial plateau fractures were evaluated by plain X-ray and magnetic resonance imaging (MRI). The type and severity of meniscus injury were diagnosed by MRI scan. Three-dimensional measurements of the lateral fragment width (LFW), the lateral plateau depression (LPD), the coronal angulation of lateral fragment (CALF), and tibial plateau widening (TPW) were measured with Picture Archiving and Communication Systems(PACS) software. The patients with and without meniscus injuries were divided into different groups and analyzed respectively. Comparison of the above measurements between the two groups was analyzed by independent t test. In all the 79 lateral tibial plateau fracture patients, 26 cases (32.9%) of meniscus injuries were detected by MRI. Among all the meniscus injury cases, 3 were of Schatzker I, 16 Schatzker II, and 7 Schatzker III. In meniscus intact group, the average LFW was (22.0±2.8) mm while in meniscus injury group it was (21.3± 3.3) mm (t=-1.008, P=0.317).The average LPD of non meniscus injury group was (5.4±2.8) mm, while in meniscus injury group was (8.7±2.8) mm (t=4.98, P=0.001). The average CALF of the two groups were 9.1°±6.1°and 10.6°± 7.1°, and there was no significant difference between the two groups (t=0.38, P=0.831). The average TPW was (3.0± 1.1) mm, and (4.8±1.7) mm of the two groups. There were significant differences between the two groups (t=5.216, P=0.001). There was no obvious correlation between the

  13. Soil moisture decline due to afforestation across the Loess Plateau, China

    Science.gov (United States)

    Jia, Xiaoxu; Shao, Ming'an; Zhu, Yuanjun; Luo, Yi

    2017-03-01

    The Loess Plateau of China is a region with one of the most severe cases of soil erosion in the world. Since the 1950s, there has been afforestation measure to control soil erosion and improve ecosystem services on the plateau. However, the introduction of exotic tree species (e.g., R. pseudoacacia, P. tabulaeformis and C. korshinskii) and high-density planting has had a negative effect on soil moisture content (SMC) in the region. Any decrease in SMC could worsen soil water shortage in both the top and deep soil layers, further endangering the sustainability of the fragile ecosystem. This study analyzed the variations in SMC following the conversion of croplands into forests in the Loess Plateau. SMC data within the 5-m soil profile were collected at 50 sites in the plateau region via field survey, long-term in-situ observations and documented literature. The study showed that for the 50 sites, the depth-averaged SMC was much lower under forest than under cropland. Based on in-situ measurements of SMC in agricultural plots and C. korshinskii plots in 2004-2014, SMC in the 0-4 m soil profile in both plots declined significantly (p resources demands in the Loess Plateau.

  14. Thorium abundances on the aristarchus plateau: Insights into the composition of the aristarchus pyroclastic glass deposits

    Science.gov (United States)

    Hagerty, Justin J.; Lawrence, D.J.; Hawke, B.R.; Gaddis, Lisa R.

    2009-01-01

    Thorium (Th) data from the Lunar Prospector gamma ray spectrometer (LP-GRS) are used to constrain the composition of lunar pyroclastic glass deposits on top of the Aristarchus plateau. Our goal is to use forward modeling of LP-GRS Th data to measure the Th abundances on the plateau and then to determine if the elevated Th abundances on the plateau are associated with the pyroclastic deposits or with thorium-rich ejecta from Aristarchus crater. We use a variety of remote sensing data to show that there is a large, homogenous portion of the pyroclastics on the plateau that has seen little or no contamination from the Th-rich ejecta of Aristarchus crater. Our results show that the uncontaminated pyroclastic glasses on Aristarchus plateau have an average Th content of 6.7 ppm and ???7 wt % TiO2. These Th and Ti values are consistent with Th-rich, intermediate-Ti yellow glasses from the lunar sample suite. On the basis of this information, we use petrologic equations and interelement correlations for the Moon to estimate the composition of the source region from which the Aristarchus glasses were derived. We find that the source region for the Aristarchus glasses contained high abundances of heat-producing elements, which most likely served as a thermal driver for the prolonged volcanic activity in this region of the Moon. Copyright 2009 by the American Geophysical Union.

  15. Peripheral laser iridoplasty opens angle in plateau iris by thinning the cross-sectional tissues

    Directory of Open Access Journals (Sweden)

    Liu J

    2013-09-01

    Full Text Available Ji Liu,1,2 Tania Lamba,1 David A Belyea1 1Department of Ophthalmology, The George Washington University, Washington DC, USA; 2Yale Eye Center, Yale University, New Haven, CT, USA Abstract: Plateau iris syndrome has been described as persistent angle narrowing or occlusion with intraocular pressure elevation after peripheral iridotomy due to the abnormal plateau iris configuration. Argon laser peripheral iridoplasty (ALPI is an effective adjunct procedure to treat plateau iris syndrome. Classic theory suggests that the laser causes the contraction of the far peripheral iris stroma, "pulls" the iris away from the angle, and relieves the iris-angle apposition. We report a case of plateau iris syndrome that was successfully treated with ALPI. Spectral domain optical coherence tomography confirmed the angle was open at areas with laser treatment but remained appositionally closed at untreated areas. Further analysis suggested significant cross-sectional thinning of the iris at laser-treated areas in comparison with untreated areas. The findings indicate that APLI opens the angle, not only by contracting the iris stroma, but also by thinning the iris tissue at the crowded angle. This is consistent with the ALPI technique to aim at the iris as far peripheral as possible. This case also suggests that spectral domain optical coherence tomography is a useful adjunct imaging tool to gonioscopy in assessing the angle condition. Keywords: plateau iris, optic coherence tomography, argon laser peripheral iridoplasty, angle-closure glaucoma

  16. Brain blood flow studies with single photon emission computed tomography in patients with plateau waves

    International Nuclear Information System (INIS)

    Hayashi, Minoru; Kobayashi, Hidenori; Kawano, Hirokazu; Handa, Yuji; Noguchi, Yoshiyuki; Shirasaki, Naoki; Hirose, Satoshi

    1986-01-01

    The authors studied brain blood flow with single photon emission computed tomography (SPECT) in two patients with plateau waves. The intracranial pressure and blood pressure were also monitored continuously in these patients. They included one patient with brain-tumor (rt. sphenoid ridge meningioma) and another with hydrocephalus after subarachnoid hemorrhage due to rupture of lt. internal carotid aneurysm. The intracranial pressure was monitored through an indwelling ventricular catheter attached to a pressure transducer. The blood pressure was recorded through an intraarterial catheter placed in the dorsalis pedis artery. Brain blood flow was studied with Headtome SET-011 (manufactured by Shimazu Co., Ltd.). For this flow measurement study, an intravenous injection of Xenon-133 of about 30 mCi was given via an antecubital vein. The position of the slice for the SPECT was selected so as to obtain information not only from the cerebral hemisphere but also from the brain stem : a cross section 25 deg over the orbito-meatal line, passing through the inferior aspect of the frontal horn, the basal ganglia, the lower recessus of the third ventricle and the brain stem. The results indicated that, in the cerebral hemisphere, plateau waves were accompanied by a decrease in blood flow, whereas, in the brain stem, the blood flow showed little change during plateau waves as compared with the interval phase between two plateau waves. These observations may explain why there is no rise in the blood pressure and why patients are often alert during plateau waves. (author)

  17. Aged dissolved organic carbon exported from rivers of the Tibetan Plateau.

    Science.gov (United States)

    Qu, Bin; Sillanpää, Mika; Li, Chaoliu; Kang, Shichang; Stubbins, Aron; Yan, Fangping; Aho, Kelly Sue; Zhou, Feng; Raymond, Peter A

    2017-01-01

    The role played by river networks in regional and global carbon cycle is receiving increasing attention. Despite the potential of radiocarbon measurements (14C) to elucidate sources and cycling of different riverine carbon pools, there remain large regions such as the climate-sensitive Tibetan Plateau for which no data are available. Here we provide new 14C data on dissolved organic carbon (DOC) from three large Asian rivers (the Yellow, Yangtze and Yarlung Tsangpo Rivers) running on the Tibetan Plateau and present the carbon transportation pattern in rivers of the plateau versus other river system in the world. Despite higher discharge rates during the high flow season, the DOC yield of Tibetan Plateau rivers (0.41 gC m-2 yr-1) was lower than most other rivers due to lower concentrations. Radiocarbon ages of the DOC were older/more depleted (511±294 years before present, yr BP) in the Tibetan rivers than those in Arctic and tropical rivers. A positive correlation between radiocarbon age and permafrost watershed coverage was observed, indicating that 14C-deplted/old carbon is exported from permafrost regions of the Tibetan Plateau during periods of high flow. This is in sharp contrast to permafrost regions of the Arctic which export 14C-enriched carbon during high discharge periods.

  18. Study on the relevance of some of the description methods for plateau-honed surfaces

    International Nuclear Information System (INIS)

    Yousfi, M; Mezghani, S; Demirci, I; El Mansori, M

    2014-01-01

    Much work has been undertaken in recent years into the determination of a complete parametric description of plateau-honed surfaces with the intention of making a link between the process conditions, the surface topography and the required functional performances. Different advanced techniques (plateau/valleys decomposition using the normalized Abbott–Firestone curve or morphological operators, multiscale decomposition using continuous wavelets transform, etc) were proposed and applied in different studies. This paper re-examines the current state of developments and addresses a discussion on the relevance of the different proposed parameters and characterization methods for plateau-honed surfaces by considering the control loop manufacturing-characterization-function. The relevance of appropriate characterization is demonstrated through two experimental studies. They consider the effect of the most plateau honing process variables (the abrasive grit size and abrasive indentation velocity in finish-honing and the plateau-honing stage duration and pressure) on cylinder liner surface textures and hydrodynamic friction of the ring-pack system. (paper)

  19. Preliminary subsurface hydrologic considerations: Columbia River Plateau Physiographic Province. Assessment of effectiveness of geologic isolation systems

    International Nuclear Information System (INIS)

    Veatch, M.D.

    1980-04-01

    This report contains a discussion of the hydrologic conditions of the Columbia River Plateau physiographic province. The Columbia River Plateau is underlain by a thick basalt sequence. The Columbia River basalt sequence contains both basalt flows and sedimentary interbeds. These sedimentary interbeds, which are layers of sedimentary rock between lava flows, are the main aquifer zones in the basalt sequence. Permeable interflow zones, involving the permeable top and/or rubble bottom of a flow, are also water-transmitting zones. A number of stratigraphic units are present in the Pasco Basin, which is in the central part of the Columbia River Plateau. At a conceptual level, the stratigraphic sequence from the surface downward can be separated into four hydrostratigraphic systems. These are: (1) the unsaturated zone, (2) the unconfined aquifer, (3) the uppermost confined aquifers, and (4) the lower Yakima basalt hydrologic sequence. A conceptual layered earth model (LEM) has been developed. The LEM represents the major types of porous media (LEM units) that may be encountered at a number of places on the Columbia Plateau, and specifically in the Pasco Basin. The conceptual LEM is not representative of the actual three-dimensional hydrostratigraphic sequence and hydrologic conditions existing at any specific site within the Columbia Plateau physiographic province. However, the LEM may be useful for gaining a better understanding of how the hydrologic regime may change as a result of disruptive events that may interact with a waste repository in geologic media

  20. Plateau hypoxia attenuates the metabolic activity of intestinal flora to enhance the bioavailability of nifedipine.

    Science.gov (United States)

    Zhang, Juanhong; Chen, Yuyan; Sun, Yuemei; Wang, Rong; Zhang, Junmin; Jia, Zhengping

    2018-11-01

    Nifedipine is completely absorbed by the gastrointestinal tract and its pharmacokinetics and metabolism may be influenced by microorganisms. If gut microbes are involved in the metabolism of nifedipine, plateau hypoxia may regulate the bioavailability and the therapeutic effect of nifedipine by altering the metabolic activity of the gut microbiota. We herein demonstrated for the first time that gut flora is involved in the metabolism of nifedipine by in vitro experiments. In addition, based on the results of 16S rRNA analysis of feces in rats after acute plateau, we first confirmed that the plateau environment could cause changes in the number and composition of intestinal microbes. More importantly, these changes in flora could lead to a slower metabolic activity of nifedipine in the body after an acute plateau, resulting in increased bioavailability and therapeutic efficacy of nifedipine. Our research will provide basis and new ideas for changes in the fecal flora of human acutely entering the plateau, and contribute to rational drug use of nifedipine.

  1. Past and future spatiotemporal changes in evapotranspiration and effective moisture on the Tibetan Plateau

    Science.gov (United States)

    Yin, Yunhe; Wu, Shaohong; Zhao, Dongsheng

    2013-10-01

    evaporative demand has decreased worldwide during the past several decades. This trend is also noted on the Tibetan Plateau, a region that is particularly sensitive to climate change. However, patterns and trends of evapotranspiration and their relationship to drought stress on the Tibetan Plateau are complex and poorly understood. Here, we analyze spatiotemporal changes in evapotranspiration and effective moisture (defined as the ratio of actual evapotranspiration (ETa) to reference crop evapotranspiration (ETo)) based on the modified Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ). Climate data from 80 meteorological stations on the Tibetan Plateau were compiled for the period 1981-2010 and future climate projections were generated by a regional climate model through the 21st century. The results show regional trends towards decreasing ETo and statistically significant increases in ETa (p stress, because of generally increased effective moisture. Future regional differences are most pronounced in terms of effective moisture, which shows notable increases in the northwestern plateau and decreases in the southeastern plateau. Moreover, the reduced magnitude of effective moisture is likely to intensify in the long term, due mainly to increased evaporative demand.

  2. Assessment of satellite rainfall products over the Andean plateau

    Science.gov (United States)

    Satgé, Frédéric; Bonnet, Marie-Paule; Gosset, Marielle; Molina, Jorge; Hernan Yuque Lima, Wilson; Pillco Zolá, Ramiro; Timouk, Franck; Garnier, Jérémie

    2016-01-01

    Nine satellite rainfall estimations (SREs) were evaluated for the first time over the South American Andean plateau watershed by comparison with rain gauge data acquired between 2005 and 2007. The comparisons were carried out at the annual, monthly and daily time steps. All SREs reproduce the salient pattern of the annual rain field, with a marked north-south gradient and a lighter east-west gradient. However, the intensity of the gradient differs among SREs: it is well marked in the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis 3B42 (TMPA-3B42), Precipitation Estimation from remotely Sensed Information using Artificial Neural Networks (PERSIANN) and Global Satellite Mapping of Precipitation (GSMaP) products, and it is smoothed out in the Climate prediction center MORPHing (CMORPH) products. Another interesting difference among products is the contrast in rainfall amounts between the water surfaces (Lake Titicaca) and the surrounding land. Some products (TMPA-3B42, PERSIANN and GSMaP) show a contradictory rainfall deficit over Lake Titicaca, which may be due to the emissivity contrast between the lake and the surrounding lands and warm rain cloud processes. An analysis differentiating coastal Lake Titicaca from inland pixels confirmed this trend. The raw or Real Time (RT) products have strong biases over the study region. These biases are strongly positive for PERSIANN (above 90%), moderately positive for TMPA-3B42 (28%), strongly negative for CMORPH (- 42%) and moderately negative for GSMaP (- 18%). The biases are associated with a deformation of the rain rate frequency distribution: GSMaP underestimates the proportion of rainfall events for all rain rates; CMORPH overestimates the proportion of rain rates below 2 mm day- 1; and the other products tend to overestimate the proportion of moderate to high rain rates. These biases are greatly reduced by the gauge adjustment in the TMPA-3B42, PERSIANN and CMORPH products, whereas a

  3. Isotope study of the groundwater of the Apodi Plateau

    International Nuclear Information System (INIS)

    Santiago, M.M.F.; Silva, C.M.S.V.; Frischkorn, H.; Manoel Filho, J.; Mendes Filho, J.

    2011-01-01

    Full text: The environmental isotopes oxygen-18 and deuterium, excellent natural tracers in hydrology, are used to characterize the groundwater stored in the Sedimentary Apodi Basin. They are originating from the Acu Sandstone Formation and from the limestone of the Jandaira Formation. These waters assist the needs from agricultural industry implanted on the top of the Apodi Plateau, responsible for the export of tropical horticulture products. This turns these waters a strategic reserve for the economic and social development of the area, and detailed knowledge of their storage and recharge conditions is necessary in order to maintain a sustainable exploration and an appropriate rational administration. With the objective of understanding the recharge mechanism and the interaction between the two aquifers, hydro chemical parameters, pH, and electric conductivity and isotopes oxygen-18 and deuterium were measured. Samples were collected in two periods, being one during the dry (set/09) and the other one at the beginning of the rainy period (jan/10). Values of δ 18 (in per mil) range from -3.5 to -2.0 in the Jandaira limestone waters, whereas they have an average of only -4.5 in Acu sandstone. Thus Jandaira values indicate the presence of recent waters and the values below - 4.0 in Acu waters indicate the presence of paleowaters, waters that should be considered as strategic reserve. The relationships between the two isotopes measured in the dry and rainy periods are described respectively by the equations δD = 4.0δO 18 - 10.5 and δD = 5.3δO 18 - 1.3. Comparing them to the classical World Meteoric Water Line (δD = 8δO 18 + 10, we identify that especially in the dry period evaporation and/or limestone dissolution play an important role. Electric conductivities of Jandaira waters range from 1000 to 3000μS/cm; waters from Acu sandstone are of lower salinity with a mean value of 500μS/cm. The relationship between the parameters oxygen-18, deuterium and electric

  4. Elevation Pattern in Growth Coherency on the Southeastern Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Lixin Lyu

    Full Text Available It is generally expected that inter-annual changes in radial growth among trees would be similar to the increase in altitude due to the limitation of increasingly harsher climatic factors. Here, we examine whether this pattern exists in alpine forests on the southeastern Tibetan Plateau. Increment cores were collected from mature trees at the lower, middle and upper limits of balfour spruce (Picea likiangensis var. balfouriana (Rehd. et Wils. Hillier ex Slsvin forests at the Buze and Yela Mountains in Basu County, Changdu Prefecture of Tibet, China. The treeline elevations are 4320 m and 4510 m a.s.l. for Buze and Yela, respectively. Tree-ring widths were measured, crossdated, and detrended to obtain a sequence of ring-width indices for each individual sample. Annual growth rate, climate sensitivity, growth-climate relationships, and growth synchrony among trees were calculated and compared across altitudes. In Buze Mountain, the annual growth rate of trees has no significant difference across altitudes. The mean sensitivity of trees is lower at the treelines than at lower elevations. Tree growth has stronger correlation with winter temperature at upper elevations than at lower elevations, has significant correlation with moisture, not temperature, in the growing season, and the growth response to moisture is lower at the treeline than at lower elevations. The correlation among individual tree-ring sequences is lower at the treeline than at sites at lower elevation. In Yela Mountain, the characterisitics of annual growth rate, mean sensitivity, tree growth-climate relationships, and inter-serial correlation are similar to those in Buze, but their differences along altitudinal gradients are less significant as those in Buze. Our data do not support the general expectation of growth convergence among individuals with increasing altitude. We conclude that individual heterogeneity and microhabitat diversity are important features for treeline trees

  5. Elevation Pattern in Growth Coherency on the Southeastern Tibetan Plateau.

    Science.gov (United States)

    Lyu, Lixin; Deng, Xu; Zhang, Qi-Bin