WorldWideScience

Sample records for pikas

  1. Plastic pikas: Behavioural flexibility in low-elevation pikas (Ochotona princeps)

    Science.gov (United States)

    Varner, Johanna; Horns, Joshua J.; Lambert, Mallory S.; Westberg, Elizabeth; Ruff, James; Wolfenberger, Katelyn; Beever, Erik; Dearing, M. Denise

    2016-01-01

    Behaviour is an important mechanism for accommodating rapid environmental changes. Understanding a species’ capacity for behavioural plasticity is therefore a key, but understudied, aspect of developing tractable conservation and management plans under climate-change scenarios. Here, we quantified behavioural differences between American pikas (Ochotona princeps) living in an atypical, low-elevation habitat versus those living in a more-typical, alpine habitat. With respect to foraging strategy, low-elevation pikas spent more time consuming vegetation and less time caching food for winter, compared to high-elevation pikas. Low-elevation pikas were also far more likely to be detected in forested microhabitats off the talus than their high-elevation counterparts at midday. Finally, pikas living in the atypical habitat had smaller home range sizes compared to those in typical habitat or any previously published home ranges for this species. Our findings indicate that behavioural plasticity likely allows pikas to accommodate atypical conditions in this low-elevation habitat, and that they may rely on critical habitat factors such as suitable microclimate refugia to behaviourally thermoregulate. Together, these results suggest that behavioural adjustments are one important mechanism by which pikas can persist outside of their previously appreciated dietary and thermal niches.

  2. PIKA as an Adjuvant Enhances Specific Humoral and Cellular Immune Responses Following the Vaccination of Mice with HBsAg plus PIKA

    Institute of Scientific and Technical Information of China (English)

    Erxia Shen; Li Li; Lietao Li; Lianqiang Feng; Lin Lu; Ziliang Yao; Haixiang Lin; Changyou Wu

    2007-01-01

    An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium (Alum, a generic term for salts of aluminium) is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA (a stabilized dsRNA) as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells (BMDCs) including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-γ production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.

  3. Adjuvant PIKA protects hepatoma cells from dengue virus infection by promoting a TBK-1-dependent innate immune response.

    Science.gov (United States)

    Zhang, Ping; Wu, Siyu; Li, Lietao; Liang, Zhaoduan; Li, Yuye; Feng, Lianqiang; Huang, Xi

    2013-04-01

    Our study presents a first investigation of the effect of the adjuvant PIKA on dengue virus (DENV) replication. PIKA pretreatment decreased the levels of DENV serotype 2 (DENV2) mRNA, protein and viral particles in the hepatoma cell line HepG2. Treatment with PIKA simultaneously with DENV2 infection, but not after infection, resulted in a protective effect. Significant induction of type I and type III interferons (IFNs), as well as interferon-stimulated genes was detected in PIKA-pretreated cells. Neutralization of IFN-β partially restored the replication levels of DENV2 in PIKA-pretreated cells, suggesting that IFN-β is one of the mediators involved in the antiviral action of PIKA. Additionally, blockade of TBK-1 signaling largely restored the IFN induction and viral suppression effects mediated by PIKA, further illustrating that PIKA plays its anti-DENV role by promoting innate immunity. These findings suggest that PIKA is an attractive agent to be used in the prevention of DENV diseases.

  4. Facing a changing world: Thermal physiology of American pikas (Ochotona princeps)

    Science.gov (United States)

    Otto, Hans W; Wilson, James A; Beever, Erik

    2015-01-01

    American pikas (Ochotona princeps) are of concern with respect to warming montane temperatures; however, little information exists regarding their physiological ability to adapt to warming temperatures. Previous studies have shown that pikas have high metabolism and low thermal conductance, which allow survival during cold winters. It has been hypothesized that these characteristics may be detrimental, given the recent warming trends observed in montane ecosystems. We examined resting metabolic rate, surface activity, and den and ambient temperatures (Ta) of pikas in late summer (August 2011 and 2012) at 2 locations in the Rocky Mountains. Resting metabolic rate was calculated to be 2.02 mL O2 · g-1h-1, with a lower critical temperature (LCT) of 28.1 ± 0.2 °C. No upper critical temperature (UCT) could be determined from our data; therefore, the estimated thermoneutral zone (TNZ) was 28.1 °C to at least 35.0 °C (upper experimental temperature). Pikas in this study showed the same bimodal above-talus activity patterns reported in previous studies. Den temperatures in Colorado were correlated with, but consistently lower than, current ambient temperatures. Wyoming den temperatures showed a weak correlation with Ta 20 min prior to the current den temperature. This study is one of few to present data on the physiological response pikas may have to current warming conditions, and the first to perform metabolic measurements in situ. Our data support conclusions of previous studies, specifically MacArthur and Wang (1973, 1974) and Smith (1974), which indicated American pikas may not have the physiological ability to cope with high Ta. Our results also highlight the importance of shaded regions below the talus rocks for behavioral thermoregulation by pikas.

  5. Effect of Hypoxia on Ldh-c Expression in Somatic Cells of Plateau Pika.

    Science.gov (United States)

    Wei, Dengbang; Wei, Linna; Li, Xiao; Wang, Yang; Wei, Lian

    2016-08-01

    Sperm specific lactate dehydrogenases (LDH-C₄) is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, Ldh-c was originally thought to be expressed only in testes and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia-tolerant mammal living 3000-5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testes and sperm, but also in the somatic tissues of plateau pika. To reveal the effect of hypoxia on pika Ldh-c expression, we investigated the mRNA and protein level of Ldh-c as well as the biochemical index of anaerobic glycolysis in pika somatic tissues at the altitudes of 2200 m, 3200 m and 3900 m. Our results showed that mRNA and protein expression levels of Ldh-c in the tissues of pika's heart, liver, brain and skeletal muscle were increased significantly from 2200 m to 3200 m, but had no difference from 3200 m to 3900 m; the activities of LDH and the contents of lactate showed no difference from 2200 m to 3200 m, but were increased significantly from 3200 m to 3900 m. Hypoxia up-regulated and maintained the expression levels of Ldh-c in the pika somatic cells. Under the hypoxia condition, plateau pikas increased anaerobic glycolysis in somatic cells by LDH-C₄, and that may have reduced their dependence on oxygen and enhanced their adaptation to the hypoxic environment.

  6. Revisiting the past to foretell the future: summer temperature and habitat area predict pika extirpations in California

    Science.gov (United States)

    Joseph A. E. Stewart; John D. Perrine; Lyle B. Nichols; James H. Thorne; Constance I. Millar; Kenneth E. Goehring; Cody P. Massing; David H. Wright; Brett Riddle

    2015-01-01

    Aim The American pika (Ochotona princeps) appears to have experienced climate mediated upslope range contraction in the Great Basin of North America, but this result has not yet been extended to other portions of the pika’s range. Our goals were: first, to determine the environmental parameters that most influence...

  7. Characterization of H7N2 Avian Influenza Virus in Wild Birds and Pikas in Qinghai-Tibet Plateau Area.

    Science.gov (United States)

    Su, Shuo; Xing, Gang; Wang, Junhua; Li, Zengkui; Gu, Jinyan; Yan, Liping; Lei, Jing; Ji, Senlin; Hu, Boli; Gray, Gregory C; Yan, Yan; Zhou, Jiyong

    2016-08-24

    Qinghai Lake is a major migrating bird breeding site that has experienced several recent highly pathogenic avian influenza virus (HPAIV) epizootics. From 2006 to 2009 we studied Qinghai's wild birds and pikas for evidence of AIV infections. We sampled 941 healthy wild animals and isolated seventeen H7N2 viruses (eight from pikas and nine from wild birds). The H7N2 viruses were phylogenetically closely related to each other and to viruses isolated in Hong Kong in the 1970s. We determined the pathogenicity of the H7N2 viruses by infecting chickens and mice. Our results suggest that pikas might play an important role in the ecology of AIVs, acting as intermediate hosts in which viruses become more adapted to mammals. Our findings of AI infection in pikas are consistent with previous observations and raise the possibility that pikas might play a previously unrecognized role in the ecology of AIVs peridomestic aquatic environments.

  8. A novel rabies vaccine based-on toll-like receptor 3 (TLR3) agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yi [Yisheng Biopharma. Co., Ltd., Beijing (China); Zhang, Shoufeng [Academy of Military Medical Sciences, Changchun (China); Li, Wei [National Center for Safety Evaluation of Drugs, Beijing (China); Hu, Yuchi; Zhao, Jinyan [Beijing Institute for Drug Control, Beijing (China); Liu, Fang; Lin, Haixiang; Liu, Yuan; Wang, Liliang; Xu, Shu [Yisheng Biopharma. Co., Ltd., Beijing (China); Hu, Rongliang, E-mail: ronglianghu@hotmail.com [Academy of Military Medical Sciences, Changchun (China); Shao, Hui, E-mail: hui.shao@yishengbio.com [Yisheng Biopharma. Co., Ltd., Beijing (China); Li, Lietao, E-mail: lietao.li@gmail.com [Yisheng Biopharma. Co., Ltd., Beijing (China)

    2016-02-15

    Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity. Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as adjuvant of rabies vaccine. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group (control) was 20–30%. According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies. - Highlights: • Vaccination alone is not effective to protect human from rabies virus infection due to delayed generation of rabies virus neutralizing antibodies (RVNA) and weak cellular immunity. • Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as an adjuvant of rabies vaccine. • The efficacy and safety of PIKA rabies vaccine was evaluated in mice. • The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. • After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group was only 20–30%. • According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. • Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to

  9. After the frass: foraging pikas select patches previously grazed by caterpillars

    Science.gov (United States)

    Barrio, Isabel C.; Hik, David S.; Peck, Kristen; Bueno, C. Guillermo

    2013-01-01

    Interactions among herbivores can shape the structure of their communities and drive their dynamics. However, detecting herbivore interactions can be challenging when they are deferred in space or time. Moreover, interactions among distantly related groups of herbivores, such as vertebrates and invertebrates, are poorly understood. We investigated the effect of invertebrate herbivory on the subsequent foraging choices of a small alpine-dwelling vertebrate, the collared pika (Ochotona collaris). We carried out a field experiment within pika territories, by presenting them with a choice of foraging sites following manipulation of invertebrate (caterpillar) herbivory. Pikas actively selected areas with increased, recent invertebrate herbivory. While the underlying mechanisms behind this interaction remain unknown, our results demonstrate a positive effect of invertebrate herbivores on subsequent vertebrate foraging preferences for the first time. Even among distantly related taxa, such interactions where one herbivore is cueing on the foraging of another, could drive the creation of herbivory hotspots, with cascading consequences for ecosystem processes. PMID:23616644

  10. Adaptive functional evolution of leptin in cold-adaptive pika family

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Aresearch team led by Prof.ZHAO Xinquan with the CAS Northwest Institute of Plateau Biology has put forward the viewpoint for the first time that adaptive functional evolution may occur in the leptin protein of the pika (Ochotona) family, a typical coldadaptive mammal.

  11. Predictors of current and longer-term patterns of abundance of American pikas (Ochotona princeps) across a leading-edge protected area

    Science.gov (United States)

    Moyer-Horner, Lucas; Beever, Erik A.; Johnson, Douglas H.; Beil, Mark; Belt, Jami

    2016-01-01

    American pikas (Ochotona princeps) have been heralded as indicators of montane-mammal response to contemporary climate change. Pikas no longer occupy the driest and lowest-elevation sites in numerous parts of their geographic range. Conversely, pikas have exhibited higher rates of occupancy and persistence in Rocky Mountain and Sierra Nevada montane ‘mainlands’. Research and monitoring efforts on pikas across the western USA have collectively shown the nuance and complexity with which climate will often act on species in diverse topographic and climatic contexts. However, to date no studies have investigated habitat, distribution, and abundance of pikas across hundreds of sites within a remote wilderness area. Additionally, relatively little is known about whether climate acts most strongly on pikas through direct or indirect (e.g., vegetation-mediated) mechanisms. During 2007–2009, we collectively hiked >16,000 km throughout the 410,077-ha Glacier National Park, Montana, USA, in an effort to identify topographic, microrefugial, and vegetative characteristics predictive of pika abundance. We identified 411 apparently pika-suitable habitat patches with binoculars (in situ), and surveyed 314 of them for pika signs. Ranking of alternative logistic-regression models based on AICc scores revealed that short-term pika abundances were positively associated with intermediate elevations, greater cover of mosses, and taller forbs, and decreased each year, for a total decline of 68% during the three-year study; whereas longer-term abundances were associated only with static variables (longitude, elevation, gradient) and were lower on north-facing slopes. Earlier Julian date and time of day of the survey (i.e., midday vs. not) were associated with lower observed pika abundance. We recommend that wildlife monitoring account for this seasonal and diel variation when surveying pikas. Broad-scale information on status and abundance determinants of montane mammals, especially

  12. The burying and grazing effects of plateau pika on alpine grassland are small: a pilot study in a semiarid basin on the Qinghai-Tibet Plateau

    Science.gov (United States)

    Yi, Shuhua; Chen, Jianjun; Qin, Yu; Xu, Gaowei

    2016-11-01

    There is considerable controversy about the effects of plateau pika (Ochotona curzoniae, hereafter pika) on alpine grassland on the Qinghai-Tibet Plateau (QTP). On the one hand, pika is considered a keystone species. On the other hand, it is being poisoned. Although significant efforts have been made to study the effects of pika at a quadrat scale ( ˜ m2), our knowledge about its distribution and effects at a larger scale is very limited. In this study, we investigated the direct effects, i.e., burying and grazing, of pika by upscaling field sampling at a quadrat scale to a plot scale ( ˜ 1000 m2) by aerial photographing. Altogether 168 plots were set on four different types of alpine grassland in a semiarid basin on the QTP. Results showed that (1) the effects of pika pile burying on the reduction of vegetation cover, biomass, soil carbon, and nitrogen were less than 10 %, which was much smaller than the effects of bald patches; and (2) pika consumed 8-21 % of annual net primary production of grassland. We concluded that the direct burying and grazing effects of pika on alpine grassland were minor in this region. The quadcopter is an efficient and economic tool for long-term repeated monitoring over large regions for further understanding the role of pika.

  13. Collared Pikas as a Model Species for Studying the Biological Impacts of Climate Change in Alpine Ecosystems

    Science.gov (United States)

    O'Donovan, K. S.; Hik, D.

    2007-12-01

    Climate models suggest that global temperatures could rise between 1.4° C and 5.8° C over the next 100 years, and that these effects will be most extreme in northern mountain regions. Pikas (Ochotona, Lagomorpha) are widespread small mammals in the alpine environments of Asia and North America. They are cold adapted and consequently sensitive to warming global temperatures. Considerable research has shown a poleward migration of many species as a result of rising temperatures, but high alpine dwelling species, like the pika, may already be trapped at the top of mountains. Little is known about the threshold values of environmental conditions under which pikas either persist or disappear. Collared pikas (Ochotona collaris) inhabit alpine meadows in the Kluane region of the southwest Yukon. Sites located along an environmental gradient from nunataks in the St Elias Icefields to the Ruby Range Mountains have experienced different climatic and glacial histories. Using baseline data from the long-term study in the Ruby Ranges, we report on differences in the ecological and climatic conditions of sites along this gradient and how this translates into differences in the behavioural and population ecology of the pikas living there. By looking at these differences we can infer the potential impacts of a warming climate, and the subsequent ecological changes on collared pika populations in order to clarify the causes of local extinction and allow us to develop models for predicting ecological responses as conditions change under future climate regimes.

  14. The idiosyncrasies of place: geographic variation in the climate-distribution relationships of the American pika.

    Science.gov (United States)

    Jeffress, Mackenzie R; Rodhouse, Thomas J; Ray, Chris; Wolff, Susan; Epps, Clinton W

    2013-06-01

    Although climate acts as a fundamental constraint on the distribution of organisms, understanding how this relationship between climate and distribution varies over a species' range is critical for addressing the potential impacts of accelerated climate change on biodiversity. Bioclimatic niche models provide compelling evidence that many species will experience range shifts under scenarios of global change, yet these broad, macroecological perspectives lack specificity at local scales, where unique combinations of environment, biota, and history conspire against generalizations. We explored how these idiosyncrasies of place affect the climate-distribution relationship of the American pika (Ochotona princeps) by replicating intensive field surveys across bioclimatic gradients in eight U.S. national parks. At macroecological scales, the importance of climate as a constraint on pika distribution appears unequivocal; forecasts suggest that the species' range will contract sharply in coming decades. However, the species persists outside of its modeled bioclimatic envelope in many locations, fueling uncertainty and debate over its conservation status. Using a Bayesian hierarchical approach, we modeled variation in local patterns of pika distribution along topographic position, vegetation cover, elevation, temperature, and precipitation gradients in each park landscape. We also accounted for annual turnover in site occupancy probabilities. Topographic position and vegetation cover influenced occurrence in all parks. After accounting for these factors, pika occurrence varied widely among parks along bioclimatic gradients. Precipitation by itself was not a particularly influential predictor. However, measures of heat stress appeared most influential in the driest parks, suggesting an interaction between the strength of climate effects and the position of parks along precipitation gradients. The combination of high elevation, cold temperatures, and high precipitation

  15. Bartonella Species Detected in the Plateau Pikas (Ochotona curzoiae) from Qinghai Plateau in China.

    Science.gov (United States)

    Rao, Hua Xiang; Yu, Juan; Guo, Peng; Ma, Yong Cheng; Liu, Qi Yong; Jiao, Ming; Ma, Zhong Wen; Ge, Hua; Wang, Chun Xiang; Song, Xiu Ping; Shi, Yan; Li, Dong Mei

    2015-09-01

    Bartonella species can infect a variety of mammalian hosts and cause a broad spectrum of diseases in humans, but there have been no reports of Bartonella infection in Ochotonidae. This is the first study to detect Bartonella in plateau pikas in the Qinghai plateau, providing baseline data for the risk assessment of human Bartonella infection in this area. We obtained 15 Bartonella strains from 79 pikas in Binggou and Maixiu areas of Qinghai with a positive rate of 18.99%. Based on the phylogenetic analysis of the Bartonella citrate synthase (gltA) gene sequences, most strains were closely related to B. taylorii (3/15) and B. grahamii (12/15). The latter is a pathogenic strain in humans. Our results suggest that a corresponding prevention and control strategy should be taken into consideration in the Qinghai province.

  16. [Functional difference of malate-aspartate shuttle system in liver between plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae)].

    Science.gov (United States)

    Zhu, Rui-Juan; Rao, Xin-Feng; Wei, Deng-Bang; Wang, Duo-Wei; Wei, Lian; Sun, Sheng-Zhen

    2012-04-25

    To explore the adaptive mechanisms of plateau zokor (Myospalax baileyi) to the enduring digging activity in the hypoxic environment and of plateau pika (Ochotona curzoniae) to the sprint running activity, the functional differences of malate-aspartate shuttle system (MA) in liver of plateau zokor and plateau pika were studied. The ratio of liver weight to body weight, the parameters of mitochondria in hepatocyte and the contents of lactic acid in serum were measured; the open reading frame of cytoplasmic malate dehydrogenase (MDH1), mitochondrial malate dehydrogenase (MDH2), and the partial sequence of aspartate glutamate carrier (AGC) and oxoglutarate malate carrier (OMC) genes were cloned and sequenced; MDH1, MDH2, AGC and OMC mRNA levels were determined by real-time PCR; the specific activities of MDH1 and MDH2 in liver of plateau zokor and plateau pika were measured using enzymatic methods. The results showed that, (1) the ratio of liver weight to body weight, the number and the specific surface of mitochondria in hepatocyte of plateau zokor were markedly higher than those of plateau pika (P 0.05); (3) mRNA level and enzymatic activity of MDH1 was significantly lower than those of MDH2 in the pika liver (P 0.05). These results indicate that the plateau zokor obtains ATP in the enduring digging activity by enhancing the function of MA, while plateau pika gets glycogen for their sprint running activity by increasing the process of gluconeogenesis. As a result, plateau pika converts the lactic acid quickly produced in their skeletal muscle by anaerobic glycolysis and reduces dependence on the oxygen.

  17. Phylogenetic relationships of five pika species (genus Ochotona) based on mitochondrial DNA restriction maps

    Institute of Scientific and Technical Information of China (English)

    于宁; 郑昌琳; 施立明; 王文; 兰宏; 张亚平

    1996-01-01

    Restriction site mapping of mitochondrial DNA (mtDNA) with 16 restriction endonucleases was used to examine the phylogenetic relationships of Ochotona cansus, O. huangensis, O. thibetana, O. curzoniae and O. erythrotis. A 1-kb length variation between 0. erythrotis of subgenus Pika and other four species of subgenus Ochotona was observed, which may be a useful genetic marker for identifying the two subgenera. The phylogenetic tree constructed using PAUP based on 61 phylogenetically informative sites suggests that O. aythrotis diverged first, followed by O. cansus, while O. atrzoniae and O. huangensis are sister taxa related to O. thibetana. The results indicate that both O. cansus and O. huangensis should be treated as independent species. If the base substitution rate of pikas mtDNA was 2% per million years, then the divergence time of the two subgenera, Pika and Ochotona, is about 8.8 Ma ago of late Miocence, middle Bao-dian of Chinese mammalian age, and the divergence of the four species in subgenus

  18. Mechanistic variables can enhance predictive models of endotherm distributions: the American pika under current, past, and future climates.

    Science.gov (United States)

    Mathewson, Paul D; Moyer-Horner, Lucas; Beever, Erik A; Briscoe, Natalie J; Kearney, Michael; Yahn, Jeremiah M; Porter, Warren P

    2017-03-01

    How climate constrains species' distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs. Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika-specific surface activity time in summer across the western United States. We then explored the difference between using a macroclimate predictor (summer temperature) and using a mechanistic predictor (predicted surface activity time) in SDMs. Both approaches accurately predicted pika presences in current and past climate regimes. However, the activity models predicted 8-19% less habitat loss in response to annual temperature increases of ~3-5 °C predicted in the region by 2070, suggesting that pikas may be able to buffer some climate change effects through behavioral thermoregulation that can be captured by mechanistic modeling. Incorporating mechanism added value to the modeling by providing increased confidence in areas where different modeling approaches agreed and providing a range of outcomes in areas of disagreement. It also provided a more proximate variable relating animal distribution to climate, allowing investigations into how unique habitat characteristics and intraspecific phenotypic variation may allow pikas to exist in areas outside those predicted by generic SDMs. Only a small number of easily obtainable data are required to parameterize this mechanistic model for any endotherm, and its use can improve SDM predictions by explicitly modeling a widely applicable direct physiological effect

  19. Mechanistic variables can enhance predictive models of endotherm distributions: The American pika under current, past, and future climates

    Science.gov (United States)

    Mathewson, Paul; Moyer-Horner, Lucas; Beever, Erik; Briscoe, Natalie; Kearney, Michael T; Yahn, Jeremiah; Porter, Warren P.

    2017-01-01

    How climate constrains species’ distributions through time and space is an important question in the context of conservation planning for climate change. Despite increasing awareness of the need to incorporate mechanism into species distribution models (SDMs), mechanistic modeling of endotherm distributions remains limited in this literature. Using the American pika (Ochotona princeps) as an example, we present a framework whereby mechanism can be incorporated into endotherm SDMs. Pika distribution has repeatedly been found to be constrained by warm temperatures, so we used Niche Mapper, a mechanistic heat-balance model, to convert macroclimate data to pika-specific surface activity time in summer across the western United States. We then explored the difference between using a macroclimate predictor (summer temperature) and using a mechanistic predictor (predicted surface activity time) in SDMs. Both approaches accurately predicted pika presences in current and past climate regimes. However, the activity models predicted 8–19% less habitat loss in response to annual temperature increases of ~3–5 °C predicted in the region by 2070, suggesting that pikas may be able to buffer some climate change effects through behavioral thermoregulation that can be captured by mechanistic modeling. Incorporating mechanism added value to the modeling by providing increased confidence in areas where different modeling approaches agreed and providing a range of outcomes in areas of disagreement. It also provided a more proximate variable relating animal distribution to climate, allowing investigations into how unique habitat characteristics and intraspecific phenotypic variation may allow pikas to exist in areas outside those predicted by generic SDMs. Only a small number of easily obtainable data are required to parameterize this mechanistic model for any endotherm, and its use can improve SDM predictions by explicitly modeling a widely applicable direct physiological effect

  20. The expression of Ldh-c in the skeletal muscle of plateau pika (Ochotona curzoniae enhances adaptation to a hypoxic environment

    Directory of Open Access Journals (Sweden)

    Zhi F. An

    2017-09-01

    Full Text Available The plateau pika (Ochotona curzoniae is a species of sprint-running alpine animals in the Qinghai-Tibet Plateau, which is a harsh highland hypoxic environment. Ldh-c is expressed in the testis, sperm and somatic tissues of plateau pika. To reveal the role and physiological mechanisms of sperm-specific lactate dehydrogenase (LDH-C4, in plateau pika to adapt to hypoxic environment, an adenoviral line of pMultiRNAi-Ldhc was constructed and injected into the bilateral biceps femoris of the hind legs. The swimming times of the pikas, and the Ldh-c expression levels, total LDH activities and ATP levels in skeletal muscle, were measured after the pikas were raised in the trapped site for 5 days. Our results showed that after Ldh-c was silenced, the sprint-running ability (swimming time of the plateau pikas was significant decreased, and the total LDH activities and ATP levels were reduced by 28.21% and 27.88%, respectively. Our results indicated that expression of Ldh-c in the skeletal muscle of plateau pika increased anaerobic glycolysis and enhanced adaptation to highland hypoxic environments.

  1. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2016-01-01

    Full Text Available Testis-specific lactate dehydrogenase (LDH-C4 is one of the lactate dehydrogenase (LDH isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4, Lactate Dehydrogenase B4 (LDH-B4, and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE and native polyacrylamide gel electrophoresis (PAGE. The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L, LDH-B4 (Ki = 23.800 mmol/L, and LDH-C4 (Ki = 65.500 mmol/L. These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4.

  2. Replicated landscape genetic and network analyses reveal wide variation in functional connectivity for American pikas.

    Science.gov (United States)

    Castillo, Jessica A; Epps, Clinton W; Jeffress, Mackenzie R; Ray, Chris; Rodhouse, Thomas J; Schwalm, Donelle

    2016-09-01

    Landscape connectivity is essential for maintaining viable populations, particularly for species restricted to fragmented habitats or naturally arrayed in metapopulations and facing rapid climate change. The importance of assessing both structural connectivity (physical distribution of favorable habitat patches) and functional connectivity (how species move among habitat patches) for managing such species is well understood. However, the degree to which functional connectivity for a species varies among landscapes, and the resulting implications for conservation, have rarely been assessed. We used a landscape genetics approach to evaluate resistance to gene flow and, thus, to determine how landscape and climate-related variables influence gene flow for American pikas (Ochotona princeps) in eight federally managed sites in the western United States. We used empirically derived, individual-based landscape resistance models in conjunction with predictive occupancy models to generate patch-based network models describing functional landscape connectivity. Metareplication across landscapes enabled identification of limiting factors for dispersal that would not otherwise have been apparent. Despite the cool microclimates characteristic of pika habitat, south-facing aspects consistently represented higher resistance to movement, supporting the previous hypothesis that exposure to relatively high temperatures may limit dispersal in American pikas. We found that other barriers to dispersal included areas with a high degree of topographic relief, such as cliffs and ravines, as well as streams and distances greater than 1-4 km depending on the site. Using the empirically derived network models of habitat patch connectivity, we identified habitat patches that were likely disproportionately important for maintaining functional connectivity, areas in which habitat appeared fragmented, and locations that could be targeted for management actions to improve functional connectivity

  3. Enzymatic Kinetic Properties of the Lactate Dehydrogenase Isoenzyme C4 of the Plateau Pika (Ochotona curzoniae)

    Science.gov (United States)

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2016-01-01

    Testis-specific lactate dehydrogenase (LDH-C4) is one of the lactate dehydrogenase (LDH) isozymes that catalyze the terminal reaction of pyruvate to lactate in the glycolytic pathway. LDH-C4 in mammals was previously thought to be expressed only in spermatozoa and testis and not in other tissues. Plateau pika (Ochotona curzoniae) belongs to the genus Ochotona of the Ochotonidea family. It is a hypoxia-tolerant species living in remote mountain areas at altitudes of 3000–5000 m above sea level on the Qinghai-Tibet Plateau. Surprisingly, Ldh-c is expressed not only in its testis and sperm, but also in somatic tissues of plateau pika. To shed light on the function of LDH-C4 in somatic cells, Ldh-a, Ldh-b, and Ldh-c of plateau pika were subcloned into bacterial expression vectors. The pure enzymes of Lactate Dehydrogenase A4 (LDH-A4), Lactate Dehydrogenase B4 (LDH-B4), and LDH-C4 were prepared by a series of expression and purification processes, and the three enzymes were identified by the method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and native polyacrylamide gel electrophoresis (PAGE). The enzymatic kinetics properties of these enzymes were studied by Lineweaver-Burk double-reciprocal plots. The results showed the Michaelis constant (Km) of LDH-C4 for pyruvate and lactate was 0.052 and 4.934 mmol/L, respectively, with an approximate 90 times higher affinity of LDH-C4 for pyruvate than for lactate. At relatively high concentrations of lactate, the inhibition constant (Ki) of the LDH isoenzymes varied: LDH-A4 (Ki = 26.900 mmol/L), LDH-B4 (Ki = 23.800 mmol/L), and LDH-C4 (Ki = 65.500 mmol/L). These data suggest that inhibition of lactate by LDH-A4 and LDH-B4 were stronger than LDH-C4. In light of the enzymatic kinetics properties, we suggest that the plateau pika can reduce reliance on oxygen supply and enhance its adaptation to the hypoxic environments due to increased anaerobic glycolysis by LDH-C4. PMID:26751442

  4. Effect of Hypoxia on Ldh-c Expression in Somatic Cells of Plateau Pika

    OpenAIRE

    Wei, Dengbang; Wei, Linna; Li, Xiao; Wang, Yang; Wei, Lian

    2016-01-01

    Sperm specific lactate dehydrogenases (LDH-C4) is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, Ldh-c was originally thought to be expressed only in testes and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia-tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testes and sper...

  5. Critical Analysis of a Social and Scientific Moral Dilemma: Fifth Graders and Veterans Respond to "Hiroshima No Pika."

    Science.gov (United States)

    Storey, Dee

    This document presents results of a survey studying the Japanese picture book, "Hiroshima No Pika." The story aptly captures how a family of three find their lives shattered in a matter of seconds when the atomic bomb is dropped on Hiroshima (Japan) in World War II. Issues presented in the story are: (1) immediate survival in the face of…

  6. Alpine biodiversity and assisted migration: The case of the American pika (Ochotona princeps)

    Science.gov (United States)

    Wilkening, Jennifer L.; Ray, Chris; Ramsay, Nathan G.; Klingler, Kelly

    2015-01-01

    Alpine mammals are predicted to be among the species most threatened by climate change, due to the projected loss and further fragmentation of alpine habitats. As temperature or precipitation regimes change, alpine mammals may also be faced with insurmountable barriers to dispersal. The slow rate or inability to adjust to rapidly shifting environmental conditions may cause isolated alpine species to become locally extirpated, resulting in reduced biodiversity. One proposed method for mitigating the impacts of alpine species loss is assisted migration. This method, which involves translocating a species to an area with more favourable climate and habitat characteristics, has become the subject of debate and controversy in the conservation community. The uncertainty associated with climate change projections, coupled with the thermal sensitivity of many alpine mammals, makes it difficult to a priori assess the efficacy of this technique as a conservation management tool. Here we present the American pika (Ochotona princeps) as a case study. American pikas inhabit rocky areas throughout the western US, and populations in some mountainous areas have become locally extirpated in recent years. We review known climatic and habitat requirements for this species, and also propose protocols designed to reliably identify favourable relocation areas. We present data related to the physiological constraints of this species and outline specific requirements which must be addressed for translocation of viable populations, including wildlife disease and genetic considerations. Finally, we discuss potential impacts on other alpine species and alpine communities, and overall implications for conserving alpine biodiversity in a changing climate.

  7. Dynamical Analysis of a Plateau Pika with Cross-Diffusion under Contraception Control

    Directory of Open Access Journals (Sweden)

    Xiaoyan Wang

    2014-01-01

    Full Text Available A plateau pika model with spatial cross-diffusion is investigated. By analyzing the corresponding characteristic equations, the local stability of an coexistence steady state is discussed when d21 is small enough. However, when d21 is large enough, the model shows Turing bifurcation if B2 -4AC > 0. Furthermore, it is proved that if, R > R0, βK > d and cross-diffusion rates are zero, the positive coexistence steady state is globally asymptotically stable. A nonconstant positive solution bifurcates from the coexistent steady state by the Leray-Schauder degree theory. Numerical simulations are carried out to illustrate the main results.

  8. Pika and vole mitochondrial genomes increase support for both rodent monophyly and glires.

    Science.gov (United States)

    Lin, Yu-Hsin; Waddell, Peter J; Penny, David

    2002-07-10

    Complete mitochondrial genomes are reported for a pika (Ochotona collaris) and a vole (Volemys kikuchii) then analysed together with 35 other mitochondrial genomes from mammals. With standard phylogenetic methods the pika joins with the other lagomorph (rabbit) and the vole with the other murid rodents (rat and mouse). In addition, with hedgehog excluded, the seven rodent genomes consistently form a homogeneous group in the unrooted placental tree. Except for uncertainty of the position of tree shrew, the clade Glires (monophyletic rodents plus lagomorphs) is consistently found. The unrooted tree obtained by ProtML (Protein Maximum Likelihood, a program in MOLPHY) is compatible with a reclassification of mammals [Syst. Biol. 48, 1-5 (1999)] which is also supported by other recent studies. However, when this tree is rooted with marsupials plus platypus, the outgroup often joins the lineage leading to the three murid rodents, so the rodents are no longer monophyletic. Apart from misplacing the root, the presence of the outgroups also distorts other parts of the unrooted tree. Either constraining the tree to maintain rodents monophyletic, or omitting murids, maintains the ingroup tree and sees the outgroup join on the edge to Xenarthra, to Afrotheria, or to these two groups together. This emphasises the importance of carrying out both an unrooted and a rooted analysis. It is known from cancer research that murid rodents have reduced activity in some DNA repair mechanisms and this alters their substitution pattern - this may be the case for mitochnodrial DNA as well. Comparing nucleotide compositions may identify taxa that differ in aspects of their DNA repair mechanisms.

  9. Herbivory and Competition of Tibetan Steppe Vegetation in Winter Pasture: Effects of Livestock Exclosure and Plateau Pika Reduction.

    Directory of Open Access Journals (Sweden)

    Richard B Harris

    Full Text Available Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP. Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae, assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures

  10. PIKA Provides an Adjuvant Effect to Induce Strong Mucosal and Systemic Humoral Immunity Against SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    Wei-wei Gai; Yan Zhang; Di-han Zhou; Yao-qing Chen; Jing-yi Yang; Hui-min Yan

    2011-01-01

    Severe Acute Respiratory Syndrome(SARS)is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especially with more efficient and economical needle-free vaccination are always needed more urgently in a pandemic.The development of a safe and effective mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.PIKA,a stabilized derivative of Poly(I:C),was previously reported to be safe and potent as adjuvant in mouse models.In the present study,we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly(I:C)derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus.Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites,co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity.When intranasal immunization was used,PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response.Overall,PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.

  11. [The expression of the sperm-specific lactate dehydrogenase gene Ldh-c in plateau pika (Ochotona curzoniae) cardiac muscle and its effect on the anaerobic glycolysis].

    Science.gov (United States)

    Li, Xiao; Wei, Lian; Wang, Yang; Xu, Li-Na; Wei, Lin-Na; Wei, Deng-Bang

    2015-06-25

    The plateau pika (Ochotona curzoniae) has a strong adaptability to hypoxic plateau environment. We found that the sperm-specific lactate dehydrogenase (LDH-C4) gene Ldh-c expressed in plateau pika cardiac muscle. In order to shed light on the effect of LDH-C4 on the anaerobic glycolysis in plateau pika cardiac muscle, 20 pikas were randomly divided into the inhibitor group and the control group, and the sample size of each group was 10. The pikas of inhibitor group were injected with 1 mL 1 mol/L N-isopropyl oxamate, a specific LDH-C4 inhibitor, in biceps femoris muscle of hind legs, each leg with 500 μL. The pikas of control group were injected with the same volume of normal saline (0.9% NaCl). The mRNA and protein expression levels of Ldh-c gene in plateau pika cardiac muscle were determined by real-time PCR and Western blot. The activities of LDH, and the contents of lactate (LD) and ATP in cardiac muscle were compared between the inhibitor group and the control group. The results showed that 1) the expression levels of Ldh-c mRNA and protein were 0.47 ± 0.06 and 0.68 ± 0.08, respectively; 2) 30 min after injection of 1 mL 1 mol/L N-isopropyl oxamate in biceps femoris muscle, the concentration of N-isopropyl oxamate in blood was 0.08 mmol/L; 3) in cardiac muscle of the inhibitor group and the control group, the LDH activities were (6.18 ± 0.48) U/mg and (9.08 ± 0.58) U/mg, the contents of LD were (0.21 ± 0.03) mmol/g and (0.26 ± 0.04) mmol/g, and the contents of ATP were (4.40 ± 0.69) nmol/mg and (6.18 ± 0.73) nmol/mg (P < 0.01); 5) the inhibition rates of N-isopropyl oxamate to LDH, LD and ATP were 31.98%, 20.90% and 28.70%, respectively. The results suggest that Ldh-c expresses in cardiac muscle of plateau pika, and the pika cardiac muscle may get at least 28% ATP for its activities by LDH-C4 catalyzed anaerobic glycolysis, which reduces the dependence on oxygen and enhances the adaptation to the hypoxic environments.

  12. Climate Tolerances and Habitat Requirements Jointly Shape the Elevational Distribution of the American Pika (Ochotona princeps), with Implications for Climate Change Effects.

    Science.gov (United States)

    Yandow, Leah H; Chalfoun, Anna D; Doak, Daniel F

    2015-01-01

    Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps) is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions.

  13. Climate Tolerances and Habitat Requirements Jointly Shape the Elevational Distribution of the American Pika (Ochotona princeps, with Implications for Climate Change Effects.

    Directory of Open Access Journals (Sweden)

    Leah H Yandow

    Full Text Available Some of the most compelling examples of ecological responses to climate change are elevational range shifts of individual species, which have been observed throughout the world. A growing body of evidence, however, suggests substantial mediation of simple range shifts due to climate change by other limiting factors. Understanding limiting factors for a species within different contexts, therefore, is critical for predicting responses to climate change. The American pika (Ochotona princeps is an ideal species for investigating distributions in relation to climate because of their unusual and well-understood natural history as well as observed shifts to higher elevation in parts of their range. We tested three hypotheses for the climatic or habitat characteristics that may limit pika presence and abundance: summer heat, winter snowpack, and forage availability. We performed these tests using an index of pika abundance gathered in a region where environmental influences on pika distribution have not been well-characterized. We estimated relative pika abundance via scat surveys and quantified climatic and habitat characteristics across two North-Central Rocky Mountain Ranges, the Wind River and Bighorn ranges in Wyoming, USA. Pika scat density was highest at mid-elevations and increased linearly with forage availability in both ranges. Scat density also increased with temperatures conducive to forage plant growth, and showed a unimodal relationship with the number of days below -5°C, which is modulated by insulating snowpack. Our results provide support for both the forage availability and winter snowpack hypotheses. Especially in montane systems, considering the context-dependent nature of climate effects across regions and elevations as well as interactions between climatic and other critical habitat characteristics, will be essential for predicting future species distributions.

  14. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika's Sprint-Running Capacity in Hypoxic Environment.

    Science.gov (United States)

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-08-07

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000-5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai-Tibet plateau

  15. Limb preference in the gallop of dogs and the half-bound of pikas on flat ground

    CERN Document Server

    Hackert, Rémi; Herbin, Marc; Abourachid, Anick; Libourel, P A

    2008-01-01

    During fast locomotion - gallop, half bound - of quadruped mammals, the ground contact of the limbs in each pair do not alternate symmetrically. Animals using such asymmetrical gait thus choose whether the left or the right limb will contact the ground first, and this gives rise to limb preference. Here, we report that dogs (Mammalia, Carnivora) and pikas (Mammalia, Lagomorpha) prefer one forelimb as trailing limb and use it as such almost twice as often as the other. We also show that this choice depends on the individual and is not a characteristic of the species, and that the strength of the preference was not dependent on the animal's running speed.

  16. Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA

    Science.gov (United States)

    Joseph A. E. Stewart; David H. Wright; Katherine A. Heckman; Robert Guralnick

    2017-01-01

    Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps...

  17. Inhibition of inducible nitric oxide synthase expression and nitric oxide production in plateau pika (Ochotona curzoniae) at high altitude on Qinghai-Tibet Plateau.

    Science.gov (United States)

    Xie, Ling; Zhang, Xuze; Qi, Delin; Guo, Xinyi; Pang, Bo; Du, Yurong; Zou, Xiaoyan; Guo, Songchang; Zhao, Xinquan

    2014-04-30

    Nitric oxide (NO), a potent vasodilator, plays an important role in preventing hypoxia induced pulmonary hypertension. Endogenous NO is synthesized by nitric oxide synthases (NOSs) from l-arginine. In mammals, three different NOSs have been identified, including neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS). Plateau pika (Ochotona curzoniae) is a typical hypoxia tolerant mammal that lives at 3000-5000 m above sea level on the Qinghai-Tibet Plateau. The aim of this study was to investigate whether NOS expression and NO production are regulated by chronic hypoxia in plateau pika. Quantitative real-time PCR and western blot analyses were conducted to quantify relative abundances of iNOS and eNOS transcripts and proteins in the lung tissues of plateau pikas at different altitudes (4550, 3950 and 3200 m). Plasma NO metabolites, nitrite/nitrate (NO(x)⁻) levels were also examined by Ion chromatography to determine the correlation between NO production and altitude level. The results revealed that iNOS transcript levels were significantly lower in animals at high altitudes (decreased by 53% and 57% at altitude of 3950 and 4550 m compared with that at 3200 m). Similar trends in iNOS protein abundances were observed (26% and 41% at 3950 and 4550 m comparing with at 3200 m). There were no significant differences in eNOS mRNA and protein levels in the pika lungs among different altitudes. The plasma NO(x)⁻ levels of the plateau pikas at high altitudes significantly decreased (1.65±0.19 μg/mL at 3200 m to 0.44±0.03 μg/mL at 3950 m and 0.24±0.01 μg/mL at 4550 m). This is the first evidence describing the effects of chronic hypoxia on NOS expression and NO levels in the plateau pika in high altitude adaptation. We conclude that iNOS expression and NO production are suppressed at high altitudes, and the lower NO concentration at high altitudes may serve crucial roles for helping the plateau pika to survive at hypoxic environment.

  18. How Far into Europe Did Pikas (Lagomorpha: Ochotonidae) Go during the Pleistocene? New Evidence from Central Iberia

    Science.gov (United States)

    Laplana, César; Sevilla, Paloma; Arsuaga, Juan Luis; Arriaza, Mari Carmen; Baquedano, Enrique; Pérez-González, Alfredo

    2015-01-01

    This paper reports the first find of pika remains in the Iberian Peninsula, at a site in central Spain. A fragmented mandible of Ochotona cf. pusilla was unearthed from Layer 3 (deposited some 63.4±5.5 ka ago as determined by thermoluminescence) of the Buena Pinta Cave. This record establishes new limits for the genus geographic distribution during the Pleistocene, shifting the previous edge of its known range southwest by some 500 km. It also supports the idea that, even though Europe’s alpine mountain ranges represented a barrier that prevented the dispersal into the south to this and other taxa of small mammals from central and eastern Europe, they were crossed or circumvented at the coldest time intervals of the end of the Middle Pleistocene and of the Late Pleistocene. During those periods both the reduction of the forest cover and the emersion of large areas of the continental shelf due to the drop of the sea level probably provided these species a way to surpass this barrier. The pika mandible was found accompanying the remains of other small mammals adapted to cold climates, indicating the presence of steppe environments in central Iberia during the Late Pleistocene. PMID:26535576

  19. Pika (Ochotona princeps) losses from two isolated regions reflect temperature and water balance, but reflect habitat area in a mainland region

    Science.gov (United States)

    Beever, Erik A.; Perrine, John D.; Rickman, Tom; Flores, Mary; Clark, John P.; Waters, Cassie; Weber, Shana S.; Yardley, Braden; Thoma, David P.; Chesley-Preston, Tara; Goehring, Kenneth E.; Magnuson, Michael; Nordensten, Nancy; Nelson, Melissa; Collins, Gail H.

    2016-01-01

    Although biotic responses to contemporary climate change are spatially pervasive and often reflect synergies between climate and other ecological disturbances, the relative importance of climatic factors versus habitat extent for species persistence remains poorly understood. To address this shortcoming, we performed surveys for American pikas (Ochotona princeps) at > 910 locations in 3 geographic regions of western North America during 2014 and 2015, complementing earlier modern (1994–2013) and historical (1898–1990) surveys. We sought to compare extirpation rates and the relative importance of climatic factors versus habitat area for pikas in a mainland-versus-islands framework. In each region, we found widespread evidence of distributional loss—local extirpations, upslope retractions, and encounter of only old sign. Locally comprehensive surveys suggest extirpation of O. princeps from 5 of 9 new sites from the hydrographic Great Basin and from 11 of 29 sites in northeastern California. Although American pikas were recorded as recently as 2011 in Zion National Park and in 2012 from Cedar Breaks National Monument in Utah, O. princeps now appears extirpated from all reported localities in both park units. Multiple logistic regressions for each region suggested that both temperature-related and water-balance-related variables estimated from DAYMET strongly explained pika persistence at sites in the Great Basin and in Utah but not in the Sierra-Cascade “mainland” portion of northeastern California. Conversely, talus-habitat area did not predict American pika persistence in the Great Basin or Utah but strongly predicted persistence in the Sierra-Cascade mainland. These results not only add new areas to our understanding of long-term trend of the American pika’s distribution, but also can inform decisions regarding allocation of conservation effort and management actions. Burgeoning research on species such as O. princeps has collectively demonstrated the

  20. Relationships of Periglacial Processes to Habitat Quality and Thermal Environment of Pikas (Lagomorpha, Ochotona) in Alpine and High-Latitude Environments (Invited)

    Science.gov (United States)

    Millar, C. I.; Smith, A. T.; Hik, D. S.

    2009-12-01

    Patterned-ground and related periglacial features such as rock-glaciers and fractured-rock talus are emblematic of cold and dry arctic environments. The freeze-thaw processes that cause these features were first systematically investigated in the pioneering work of Linc Washburn. Unusual internal and autonomous micro-climatic and hydrologic processes of these features, however, are only beginning to be understood. Such features occur also in temperate latitude mountains, often in surprising abundance in regions such as the Great Basin (NV, USA) and San Juan Mtns (CO, USA), where they occur as active as well as relict (neoglacial or Pleistocene) features. Rock-dwelling species of pikas (Ochotona) in temperate North American and Asian mountains and in North American high-latitudes have long been known for their preference for talus habitats. We are investigating geomorphic, climatic, and hydrologic attributes of these periglacial features for their role in habitat quality and thermal environment of pikas. PRISM-modeled and observed climatic conditions from a range of talus types for Ochotona princeps in California and the western Great Basin (USA) indicate that, 1) thermal conditions of intra-talus-matrix in summer are significantly colder than talus-surface temperatures and colder than adjacent slopes and forefield wetlands where pika forage; 2) near-talus-surface locations (where haypiles are situated) are warmer in winter than intra-talus-matrix temperatures; 3) high-quality wetland vegetation in talus forefields is promoted by year-round persistence of outlet springs, seeps, and streams characteristic of active taluses. The importance of snowpack to winter thermal conditions is highlighted from these observations, suggesting a greater sensitivity of habitat in dry temperate regions such as eastern California and Nevada USA to warming winter minimum temperatures than in regions or elevations where snowpacks are more persistent. In regions where warming air

  1. Science Challenges in Supporting Adaptation Planning in Mountainous Terrain: Lessons from the NOAA climate assessment to inform the FWS Status Review of the American pika

    Science.gov (United States)

    Ray, A. J.; Barsugli, J. J.; Eischeid, J.; Wolter, K.

    2010-12-01

    This presentation will summarize results and some of the scientific challenges that were faced in preparing a NOAA rapid assessment of climate provided as input to the Fish & Wildlife Service review of the American Pika to determine if climate change risks warranted listing the species as endangered. NOAA provided FWS with an assessment of climate observations and projections of change in pika habitat, as a climatological context for the status review. We provided western regional detail based on existing observations and IPCC model projections and new findings from interpreting those observations and projections at smaller spatial scales. A key finding of the report is the large spatial scale of recent and projected warming trends in the West. The 2050 summer temperature projections average about 3°C higher than recent climatology for most of the western U.S., and for 22 locations representative of pika habitats. Statistically downscaled temperature projections were used to relate these large-scale trends to habitat elevation bands. Finally, we provided an expert judgment on the “foreseeable future” for climate for the review. This project required considering the observations and projections in the context of the heterogeneous terrain that is the habitat for many pika populations, and interpreting and interpolating information from often distant observing stations, or large-scale model grid-boxes to make inferences about conditions at finer scales. This presentation will discuss the findings of the report, and some of the strategies that we adopted for analyzing and presenting climate projections. The emphasis will be on this real-world example where time and resource constraints were paramount, as well as the need to use “best available science,” in the context of a formal policy process vs. time to develop new work. Some of the challenges we faced are applicable to many ecological applications and for many individual species, including the choice of

  2. Why museums matter: a tale of pinworms (Oxyuroidea: Heteroxynematidae) among pikas (Ochotona princeps and O. collaris) in the American west.

    Science.gov (United States)

    Hoberg, E P; Pilitt, P A; Galbreath, K E

    2009-04-01

    Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only 2 species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependant on accurate and definitive

  3. First description of the nymph and larva of Dermacentor raskemensis (Acari: Ixodidae), parasites of pikas and other small mammals in Central Asia.

    Science.gov (United States)

    Apanaskevich, Dmitry A

    2013-09-01

    Dermacentor raskemensis Pomerantzev, 1946 is one of the rare Asian species in this genus. The immature stages of this species have never been described. Reexamination of D. raskemensis holdings stored in the United States National Tick Collection revealed a collection lot containing reared nymphs and larvae of this species. This collection made it possible for us to find numerous nymphs and larvae of D. raskemensis among previously unidentified material collected in the field. Both immature stages of D. raskemensis are described here for the first time. Nymphs of D. raskemensis can be distinguished from those of other Dermacentor species in the region by small spiracular plate, relatively short and obtuse lateral projections of basis capituli dorsally, relatively short spurs on coxa I and the internal spur is characteristically very broadly rounded at its apex, and very small spur on coxa IV, whereas larvae of D. raskemensis can be distinguished from other Dermacentor by relatively short and obtuse lateral projections of basis capituli, approximately 6 denticles in the median files on hypostome, and relatively short, broad, and rounded spur on coxa I. The nymphs and larvae of D. raskemensis studied originate from Afghanistan, India, Iran, and Pakistan, where they were collected from pikas and other small mammals.

  4. Abrupt motion tracking of plateau pika (Ochotona curzoniae) based on local texture and color model%基于纹理颜色模型的高原鼠兔突变运动跟踪

    Institute of Scientific and Technical Information of China (English)

    陈海燕; 张爱华; 胡世亚

    2016-01-01

    针对自然生境环境下高原鼠兔跟踪中,鼠兔毛色呈保护色与背景颜色相近以及运动随机的问题,构造了一种局部纹理差异性算子LTDC(local ternary difference count),来表征目标和背景之间的细微差异性,弥补了采用单一LTC(local ternary count)算子的不足。通过运动信息来判断鼠兔的运动模式,不同的模式采用不同的采样跟踪策略。把所构造的LTDC算子与R(red)G(green)B(blue)颜色信息相结合来表示目标,并把该目标表示模型引入到运动信息引导的高原鼠兔跟踪方法中。通过对采集的秋冬季节高原鼠兔视频图像进行测试,分析跟踪的成功率和误差,得到的 LTDC 纹理颜色模型的目标表示方法在鼠兔发生突变运动时,由于采用了运动信息引导的采样跟踪方式,能够有效地捕获突变目标,跟踪成功率达到97.93%。在鼠兔发生平滑运动时,尽管目标与背景颜色相近,依然能够稳定地跟踪目标,跟踪误差较小,误差波动范围也较小,误差均值为19.56,误差方差为74.24。试验结果表明:所提出的跟踪方法具有较强的目标与背景区分能力,在目标和背景颜色相近、运动复杂的场景中,能够较为准确地实现高原鼠兔目标的定位。%Plateau pika(Ochotona curzoniae) is one of the main biological disasters in the Qinghai-Tibet plateau and adjacent areas in China. Video-based animal behavior analysis is a critical and fascinating problem for both biologists and computer vision scientists. According to the color similarity betweenPlateau pika and the background, as well as the uncertainty and randomness of plateau pika motion in natural habitat environment, a new visual descriptor named the local texture difference operator LTDC was proposed to reflect the subtle differences between the plateau pika and the background. The LTDC operator, being more robust to target expression

  5. The Interaction Between Plateau pikas (Ochotona curzoniae) and White rumpped snow-finches(Pyrilauda taczanowskii)at Nian village , Rutog Township of Medrolgongkar County%西藏拉萨市墨竹工卡县日多镇念村高原鼠兔与白腰雪雀的生态关系探讨

    Institute of Scientific and Technical Information of China (English)

    米玛旺堆; 次旦吉美

    2015-01-01

    Study on the interaction between plateau pikas (Ochotona curzoniae) and white rumpped snow-finches (Pyrilauda taczanowskii)was carried out from the 17th to 14th of Jan in 2014 at Nian village, Rutog Township of Medrolgongkar County. The results showed that there was a significant positive correlation between the numbers of burrow of plateau pikas and white rumpped snow-finches numbers. The mutualism or commensalism between plateau pikas and wite rummped snow finches was indicated. Yet this needs to be further fested based on both observational and experimental studies.%2014年1月7日至14日在西藏拉萨市墨竹工卡县日多镇念村,以牦牛白天取食和夜宿地作为采样点,对高原鼠兔(Ochotona curzoniae)和白腰雪雀(Pyrilauda taczanowskii)的生态关系进行分析.研究者分别对高原鼠兔、白腰雪雀的数目及高原鼠兔的洞穴数目进行统计,并分析了高原鼠兔与白腰雪雀之间的生态关系.研究结果表明,高原鼠兔与白腰雪雀在数量上存在正相关.

  6. 高原鼠兔繁殖期攻击行为的动态格局%Variation in aggressive behavior of plateau pikas (Ochotona curzoniae) during different breeding seasons

    Institute of Scientific and Technical Information of China (English)

    陈千权; 曲家鹏; 张堰铭

    2013-01-01

    为探讨高原鼠兔繁殖期攻击行为强度的变化、检验进化博弈理论有关预测,本研究于2009年5~8月采用标志重捕和中立竞技场法测定了高原鼠兔自然种群斗殴及进攻等行为的发生频率及持续时间.结果表明:5月下旬及6月上旬高原鼠兔雄性斗殴行为发生频率及持续时间显著高于7月下旬和8月中旬;而雌性差异不显著.5月下旬和6月上旬,高原鼠兔雄性个体间的斗殴行为发生频率及持续时间显著高于雌性,其余时期两性间无显著差异.进攻发起者通常是该次殴斗的获胜者;自繁殖高峰期至末期,种群中雄性高原鼠兔鹰对策者比例逐渐下降,与进化博弈论的预测一致.%In order to explore the variation of aggressive level in a plateau pika (Ochotona curzoniae) population during different breeding seasons and test the predictions of evolutionary game theory,the methods of mark recapture and neutral arena were used to measure the frequencies and durations of fight behaviors of plateau pikas in the wild from May to August 2009.Frequencies and durations of fight behaviors between males from later May to early June were significantly higher than those from later July to middle August,while no significant differences of these two parameters between female were detected during the whole study period.Frequencies and durations of fight behaviors between males were significantly higher than those between females from later May to early June,while no significant differences of these two parameters between sexes were detected among other periods.The initiator of a fight was always the winner.Aggressor proportions in the population declined after the peak of reproductive cycle,which coincided with the predictions of evolutionary game theory.

  7. 森林鼠兔害发生特点及防控措施%Study on the occurrence characteristics of forest pika disaster and its control measures of Mulan Forestry Administration

    Institute of Scientific and Technical Information of China (English)

    马莉

    2015-01-01

    Since the 70’s of the last century , the Mulan Forestry Administration has wit‐nessed the pika hazard occurrence in artificial larch and Pinus tabulae f ormis forest in new plantation from sporadically into widespreadedly ,which endangers both the development of newly planted saplings of L arix gmelinii ,Pinus tabuli f ormis ,Pinus sylvestris ,Picea aspe‐rata plantation and greening seedlings ,affecting the afforestation effect ,reducing the eco‐nomic benefits of greening seedlings .In the practice ,effective prevention and treatments are conducted with the original apple cuts mixed with zinc phosphide ,wheat mixed with broma‐diolone ,seedling trunks smeared with repellent ,baits by dosing protector ,indicating that there is a continuous progress in its prevention and control technology ,and therefore the afforestation achievements have been effectively protected ,and an advanced ,well feasible , and economical prevention and control technology has been established .%自20世纪70年代开始,木兰林区森林鼠兔害由零星发生转化为普遍发生,由危害新造林地幼树发展到危害落叶松、油松、樟子松、云杉幼林地及绿化大苗,影响造林绿化成效,降低绿化大苗经济效益。为防控鼠兔危害,主要采取了苹果切块拌磷化锌、小麦拌溴敌隆、苗干涂抹驱避剂、保护器投药饵等方法,有效地保护了造林成果,在实践中逐渐探索出一条技术先进、生产可行、经济上合算的防治技术措施。

  8. Functional difference of malate-aspartate shuttle system in liver between plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae)%高原鼢鼠和高原鼠兔肝脏苹果酸天冬氨酸穿梭系统的功能差异

    Institute of Scientific and Technical Information of China (English)

    朱瑞娟; 饶鑫峰; 魏登邦; 王多伟; 魏莲; 孙生祯

    2012-01-01

    To explore the adaptive mechanisms of plateau zokor (Myospalax baileyi) to the enduring digging activity in the hypoxic environment and of plateau pika (Ochotona curzoniae) to the sprint running activity, the functional differences of malate-aspartate shuttle system (MA) in liver of plateau zokor and plateau pika were studied. The ratio of liver weight to body weight, the parameters of mitochondria in hepatocyte and the contents of lactic acid in serum were measured; the open reading frame of cytoplasmic malate dehydrogenase (MDH1), mitochondrial malate dehydrogenase (MDH2), and the partial sequence of aspartate glutamate carrier (AGC) and oxoglutarate malate carrier (OMC) genes were cloned and sequenced; MDH1, MDH2, AGC and OMC mRNA levels were determined by real-time PCR; the specific activities of MDHI and MDH2 in liver of plateau zokor and plateau pika were measured using enzymatic methods. The results showed that, (1) the ratio of liver weight to body weight, the number and the specific surface of mitochondria in hepatocyte of plateau zokor were markedly higher than those of plateau pika (P 0.05); (3) mRNA level and enzymatic activity of MDHl was significantly lower than those of MDH2 in the pika liver (P 0.05). These results indicate that the plateau zokor obtains ATP in the enduring digging activity by enhancing the function of MA, while plateau pika gets glycogen for their sprint running activity by increasing the process of gluconeogenesis. As a result, plateau pika converts the lactic acid quickly produced in their skeletal muscle by anaerobic glycolysis and reduces dependence on the oxygen.%为了探讨高原鼢鼠(Myospalax baileyi)和高原鼠兔(Ochotona curzoniae)在低氧环境下适应耐力性挖掘活动和快速奔跑的生理机制,本文比较研究了这两种高原动物肝脏中苹果酸天冬氨酸穿梭系统(malate-spartate shuttle system,MA)的功能差异.测定高原鼢鼠和高原鼠兔的肝脏体重比、肝细胞中线粒体参

  9. Efficacies of coccidian parasites (Protozoa) in control of plateau pika (Ochotona curzoniae) and their effects on embryo development%艾美尔球虫防治高原鼠兔实验及对其胚胎发育的影响

    Institute of Scientific and Technical Information of China (English)

    杜寅; 曹伊凡; 景增春; 何慧; 边疆晖

    2012-01-01

    The plateau pika (Ochotona curzoniae) has been recorded as one of the serious pests in alpine meadows on the Qinghai-Tibet Plateau. However, biological control, recognized as a primary way in pest control, generally does not display visible effectiveness in the short term. Coccidian parasites are intestinal protozoans, and are currently recognized as the main parasite infecting plateau pika populations. Infection with coccidia seriously impairs the survival of hosts. In order to test whether coccidia could be used for control pikas, we incorporated coccidia into bait and tested its efficacies in both laboratory and field. Our results showed that the bait ( containing 300 × 10 oocysts and synergist) led 63. 6% adults to die in the laboratory, and 54.9% and 71.0% decreases in numbers of adults and juveniles in field, respectively. In addition, embryo weight was significant lower in the treatment group than that in the control group. Infection rate and infection intensity were significantly higher in treatment plots than those in control plots. Our results suggest that coccidian parasites have good effectiveness in pika control, and it may also influence embryo development of pregnant female infected in the field.%高原鼠兔是青藏高原地区危害高寒草甸植被的主要有害小哺乳动物.生物控制为有害动物防治的主要发展方向,但存在防治效果见效慢的缺点.艾美尔球虫是高原鼠兔肠道内的主要寄生物,并对宿主具有专一性寄生的特点.为将艾美尔球虫研发成新型的高原鼠兔无公害生物防治制剂,本文测定了球虫毒饵对高原鼠兔致死率并在野外进行了灭鼠实验.结果表明,添加增效剂的300万球虫毒饵在室内可导致63.6%的成年个体死亡,在野外可导致54.9%成体和71.0%幼体死亡.灭鼠后残存高原鼠兔的球虫感染率和感染强度显著大于对照个体,且妊娠雌体的胚胎重较对照显著降低.上述结果说明,艾美尔球虫

  10. Effect of Two Sexes Sterile Rodenticide (Neem Oil) on Food Intake of Plateau Pika%两性不育灭鼠剂印楝油对高原鼠兔摄食量的影响及药效试验研究

    Institute of Scientific and Technical Information of China (English)

    龙兴发; 李太强; 殷中琼; 蒋忠荣; 朱连发; 杨秀全

    2011-01-01

    通过对高原鼠兔野外饲养和印楝油摄食量的药效观察试验,选取高原鼠兔90只,分成2个试验组和1个对照组,各试验组投药浓度为30%和40%的印楝油;对照组饲喂青草,用药7d。试验期间观察各组鼠兔的临床表现,每天记录颗粒剂的采食量,并计算摄食系数;停药后27d处死,剖检雄雌鼠,做病理切片,剖开雌鼠子宫,统计怀孕率。结果表明,高原 药浓度 、40%的颗粒剂的摄食率分别为11.09%和25.10%,差异显著(P〈0.05);筛选出主药浓度为40 两性不 颗粒剂适口性良好,对高原鼠兔有良好的抗生%This article carried out, and 90 plateau the study on effect of rodenticide(neem oil) on food intake of plateau pika in the fields was pikas were selected and allocated into two experimental groups and one control group, the concentration of neem oil of

  11. The seasonal changes of plant secondary metabolites and their influence on the food selection of plateau pika%植物次生代谢物含量的季节性变化及其对高原鼠兔食物选择的影响

    Institute of Scientific and Technical Information of China (English)

    戴鑫; 顾新州; 石佳; 袁飞; 殷宝法; 王爱勤; 魏万红; 杨生妹

    2012-01-01

    The research was carried out from June to September 2008 in the Haibei Alpine Meadow Ecosystem Research Station, Chinese Academy of Science, Qinghai Province. Plateau pikas (Ochotona curzoniae) were fed 20 different plants and the amounts of consumed food were measured using a cafeteria preference test. Seasonal changes of 4 plant secondary metabolites (PSMs) , flavonoids, condensed tannins, simple phenols and total phenols in the 20 plants were determined by ultraviolet spectrophotometer. The results for the 20 plants showed that the groups of favored plants and edible plants for plateau pikas comprised 7 species each, the remaining 6 species were anorectic plants. There were some differences between plant species for the 4 PSMs some of which showed seasonal changes - they tended to be the lowest in the beginning of growing season and gradually increased in the following months. The contents of condensed tannins in the favored group was significantly lower than in the edible group, and the content of flavonoids in the favored group was significantly lower than in the anorectic group. There was a significant negative correlation between the amount of food intake and the contents of flavonoids in all 20 plants. Within the favored plant group, the plant intake amount was negatively correlated with simple phenols and total phenols content. The results partly verified the hypothesis that plant secondary metabolites serve a defense strategy that could significantly influence the plants' selection as food by Ochotona curzoniae. Flavonoids were the factor which significantly restrained the plant food selection of plateau pikas and condensed tannins could deter the plant food selection of plateau pikas in some extent, and results demonstrated that plateau pikas might have a food selection strategy to forage on the plants with high contents of simple phenols or total phenols in relative small quantities, but avoid foraging them in large doses.%2008年6~9月在中国科

  12. Kasulik on puhata pikas kuus / Mati Feldmann

    Index Scriptorium Estoniae

    Feldmann, Mati, 1961-

    2005-01-01

    Äripäeva arvamustoimeteja selgitab, miks fikseeritud kuupalga juures on kasulikum puhata kalendrikuus, milles on rohkem kalendripäevi ja analüüsib, milline suvekuu on puhkuseks rahaliselt soodsaim

  13. Kõusaare film teenis Cannes'is pika aplausi / Annika Koppel

    Index Scriptorium Estoniae

    Koppel, Annika

    2007-01-01

    60-ndast Cannes'i filmifestivalil esilinastus 18. mail Kadri Kõusaare mängufilm "Magnus" võistlusprogrammis "Vaatenurk". Filmist ja selle vastuvõtust Cannes'is. Ka Michael Moore'ist ja tema dokumentaalfilmist "Sicko"

  14. Kõusaare film teenis Cannes'is pika aplausi / Annika Koppel

    Index Scriptorium Estoniae

    Koppel, Annika

    2007-01-01

    60-ndast Cannes'i filmifestivalil esilinastus 18. mail Kadri Kõusaare mängufilm "Magnus" võistlusprogrammis "Vaatenurk". Filmist ja selle vastuvõtust Cannes'is. Ka Michael Moore'ist ja tema dokumentaalfilmist "Sicko"

  15. E-raamatukogu tuleb pika sammuga! / Janne Andresoo

    Index Scriptorium Estoniae

    Andresoo, Janne, 1965-

    2009-01-01

    Eesti Rahvusraamatukogu lähiaastate strateegia on seadnud eesmärgiks traditsioonilise raamatukogu ja e-raamatukogu funktsioonide liitmise. RR-i arendusprojektidest e-raamatukogu arendamisel. Mälu- ja teadusasutuste koostöö e-ressursside koondamisel viib 2013. aastaks Eesti raamatukogude otsinguportaalini ning Eesti Digitaalarhiivini

  16. E-raamatukogu tuleb pika sammuga! / Janne Andresoo

    Index Scriptorium Estoniae

    Andresoo, Janne, 1965-

    2009-01-01

    Eesti Rahvusraamatukogu lähiaastate strateegia on seadnud eesmärgiks traditsioonilise raamatukogu ja e-raamatukogu funktsioonide liitmise. RR-i arendusprojektidest e-raamatukogu arendamisel. Mälu- ja teadusasutuste koostöö e-ressursside koondamisel viib 2013. aastaks Eesti raamatukogude otsinguportaalini ning Eesti Digitaalarhiivini

  17. Castro loobumine toob Kuubale üle pika ajal valimispõnevuse / Evelyn Kaldoja

    Index Scriptorium Estoniae

    Kaldoja, Evelyn, 1980-

    2008-01-01

    Ilmunud ka: Postimees : na russkom jazõke 20. veebr. 2008, lk. 5. Kuuba riigipea Fidel Castro teatas pensionileminekust, Kuuba rahvusassamblee määrab uue presidendi. Vt. samas: Fidel Castro poolsajand Vabaduse Saarel

  18. "Sepp ja Ojuland annavad Ergmale pika puuga!" / interv. Katrin Pauts, Marilin Vikat

    Index Scriptorium Estoniae

    2005-01-01

    Aarne Valmis, Anu Saagim, Jaanus Raidal, Paavo Pärn, Andrus Raissaar, Margit Jõgger, Raivo Kiisler, Imre Rammul, Eve Kivi, Erich Krieger, Jüri Kullamaa, Tiina Park, Auris Rätsep ja Laura Ennet vastavad küsimusele, kes on nende arvates Eesti seksikaim naispoliitik. Vt. samas intervjuud Kristiina Ojulandi, Raimo Kägu, Evely Sepaga; Kroonika seksikaima valimisel naispoliitikud tabeli lõpus; Seksikaimad naispoliitikud; Poliitika lämmatab seksapiili?

  19. Pika ootamise järel tekkis lootus / Marko Suurmägi

    Index Scriptorium Estoniae

    Suurmägi, Marko, 1975-

    2008-01-01

    Viljandi veekeskuse ehitamiseks esitati kolm projekti, mille autoriteks on arhitektuuribüroo Koko (ehitaja Leviehitus), Velle Kadalipp ja arhitektuuribüroo JVR (kaks erinevat projekti, ehitajad Akriptor ja Viljandi Metall)

  20. Dunker jäi Lätis pika ninaga / Piret Reiljan

    Index Scriptorium Estoniae

    Reiljan, Piret, 1983-

    2007-01-01

    Ilmunud ka: Delovõje Vedomosti 15. aug. lk. 9. Dunkri Kaubanduse AS pidi loobuma Läti importalkoholi hulgimüüja Lion ostmisest, kuna pooled ei jõudnud tehingu maksumuses kokkuleppele. Kommenteerib Alexander Bondarev. Tabel: Dunkri käive kasvas mullu üle 40%. Lisa: Lion. Vt. samas: Tehingu katkemine pidurdab laienemist

  1. Castro loobumine toob Kuubale üle pika ajal valimispõnevuse / Evelyn Kaldoja

    Index Scriptorium Estoniae

    Kaldoja, Evelyn, 1980-

    2008-01-01

    Ilmunud ka: Postimees : na russkom jazõke 20. veebr. 2008, lk. 5. Kuuba riigipea Fidel Castro teatas pensionileminekust, Kuuba rahvusassamblee määrab uue presidendi. Vt. samas: Fidel Castro poolsajand Vabaduse Saarel

  2. Dunker jäi Lätis pika ninaga / Piret Reiljan

    Index Scriptorium Estoniae

    Reiljan, Piret, 1983-

    2007-01-01

    Ilmunud ka: Delovõje Vedomosti 15. aug. lk. 9. Dunkri Kaubanduse AS pidi loobuma Läti importalkoholi hulgimüüja Lion ostmisest, kuna pooled ei jõudnud tehingu maksumuses kokkuleppele. Kommenteerib Alexander Bondarev. Tabel: Dunkri käive kasvas mullu üle 40%. Lisa: Lion. Vt. samas: Tehingu katkemine pidurdab laienemist

  3. Pow, Punch, Pika, and Chu : The Structure of Sound Effects in Genres of American Comics and Japanese Manga

    NARCIS (Netherlands)

    Pratha, Nimish K.; Avunjian, Natalie; Cohn, Neil

    2016-01-01

    As multimodal works, comics are characterized as much by their use of language as by the style of their images. Sound effects in particular are exemplary of comics’ language-use, and we explored this facet of comics by analyzing a corpus of books from genres in the United States (mainstream and inde

  4. Tšaad karistas prantslastest lapseröövijaid pika sunnitööga / Hendrik Vosman

    Index Scriptorium Estoniae

    Vosman, Hendrik

    2007-01-01

    Tšaadi kohus mõistis süüdi Prantsuse heategevusorganisatsiooni LþArche de Zoe kuus töötajat 103 lapse röövimise katses ja otsustas nad kaheksaks aastaks sunnitööle saata. Lisa: LþArche de Zoe

  5. Eesti jätab Soome kiire traadita internetiühenduse osas pika ninaga / Askur Alas

    Index Scriptorium Estoniae

    Alas, Askur, 1973-

    2006-01-01

    2007. aastal kaetakse kogu Eesti kiire traadita andmesidevõrguga. Riigi infosüsteemide arenduskeskuse osakonnajuhataja Margus Kreinini selgitusi. Lisa: Uus põlvkond. Mis on wimax? Vt. samas: Wimaxi kuutasu on tavalise koduvõrgu omast suurem

  6. Pow, Punch, Pika, and Chu : The Structure of Sound Effects in Genres of American Comics and Japanese Manga

    NARCIS (Netherlands)

    Pratha, Nimish K.; Avunjian, Natalie; Cohn, Neil

    2016-01-01

    As multimodal works, comics are characterized as much by their use of language as by the style of their images. Sound effects in particular are exemplary of comics’ language-use, and we explored this facet of comics by analyzing a corpus of books from genres in the United States (mainstream and

  7. Perseverance of pikas in the Miocene : Interplay of climate and competition in the evolution of Spanish Ochotonidae (Lagomorpha, Mammalia). Geologica Ultraiectina (333)

    NARCIS (Netherlands)

    Hordijk, K.

    2010-01-01

    The sedimentary succession near the village of Villafeliche in the Calatayud-Montalbán Basin (Spain) is well known for its very rich, densely sampled and well dated fossil mammal record of Miocene age and roughly spans the time interval between 17 and 10 million years ago. The exceptional quality of

  8. Tulumaksukohustuse edasilükkamisest väärtpaberite võõrandamisel ehk Kuidas metsamehed Riigikohtus maksuhaldurile pika puuga ära tegid / Gaily Kuusik

    Index Scriptorium Estoniae

    Kuusik, Gaily

    2009-01-01

    Sylvesteri kohtuasjas tehtud Riigikohtu lahendist 3-3-1-23-09: Maksu- ja Tolliameti Lõuna maksu- ja tollikeskuse kassatsioonkaebus Tartu Ringkonnakohtu 19. jaanuari 2009. a otsuse peale haldusasjas nr 3-07-1205. Lisa: Kastekann trepil ja teeninduslik retoorika : noppeid Sylvesteri maksuvaidluse kohtutoimikust. Maksu- ja Tolliameti ja AS Sylvesteri vaheline maksuvaidlus on lõppenud : MTA pressiteade 06. 06. 2009. Õige mees õigel ajal õiges kohas

  9. Tulumaksukohustuse edasilükkamisest väärtpaberite võõrandamisel ehk Kuidas metsamehed Riigikohtus maksuhaldurile pika puuga ära tegid / Gaily Kuusik

    Index Scriptorium Estoniae

    Kuusik, Gaily

    2009-01-01

    Sylvesteri kohtuasjas tehtud Riigikohtu lahendist 3-3-1-23-09: Maksu- ja Tolliameti Lõuna maksu- ja tollikeskuse kassatsioonkaebus Tartu Ringkonnakohtu 19. jaanuari 2009. a otsuse peale haldusasjas nr 3-07-1205. Lisa: Kastekann trepil ja teeninduslik retoorika : noppeid Sylvesteri maksuvaidluse kohtutoimikust. Maksu- ja Tolliameti ja AS Sylvesteri vaheline maksuvaidlus on lõppenud : MTA pressiteade 06. 06. 2009. Õige mees õigel ajal õiges kohas

  10. Perseverance of pikas in the Miocene : Interplay of climate and competition in the evolution of Spanish Ochotonidae (Lagomorpha, Mammalia). Geologica Ultraiectina (333)

    NARCIS (Netherlands)

    Hordijk, K.

    2010-01-01

    The sedimentary succession near the village of Villafeliche in the Calatayud-Montalbán Basin (Spain) is well known for its very rich, densely sampled and well dated fossil mammal record of Miocene age and roughly spans the time interval between 17 and 10 million years ago. The exceptional quality of

  11. The Influence of Red Fox′s Odor on the Reproduction of the Plateau Pika%赤狐气味对高原鼠兔繁殖的影响

    Institute of Scientific and Technical Information of China (English)

    魏万红; 曹伊凡; 张堰铭; 殷宝法; 王金龙

    2004-01-01

    在野外条件下,利用赤狐的粪尿气味增加高原鼠兔的捕食风险,研究捕食风险对高原鼠兔繁殖的影响.结果表明,作为衡量高原鼠兔繁殖投入大小的定量指标,成体高原鼠兔的体重变化在捕食风险处理样方与对照样方之间没有明显的不同,随着繁殖期的延长,两样方内雌雄个体的体重均显著减少,说明捕食风险对高原鼠兔的繁殖投入无明显影响,因此,捕食风险对幼体的生长、发育也无明显的作用.捕食风险增加后,高原鼠兔平均每个雌性成体拥有的后代数目、性比和居留率与对照样方比较均无明显不同,但是由于扩散等原因使每个雄性成体拥有的后代数、繁殖期结束后幼体的性比有明显的差异.以上结果并未显示出捕食者气味作为捕食风险对高原鼠兔的繁殖产生抑制作用,其主要原因是捕食风险的类型不同和研究期间高原鼠兔本身承受的捕食风险较大,高原鼠兔可能通过行为变化调节捕食风险增加对其产生的不利影响.

  12. Understanding relationships among abundance, extirpation,and climate at ecoregional scales

    Science.gov (United States)

    Beever, Erik A.; Solomon Dubrowski,; ,; ,; J. Long,; ,; A. Mysnberge,; Piekielek, N. B.

    2014-01-01

    Recent research on mountain-dwelling species has illustrated changes in species’ distributional patterns in response to climate change. Abundance of a species will likely provide an earlier warning indicator of change than will occupancy, yet relationships between abundance and climatic factors have received less attention. We tested whether predictors of counts of American pikas (Ochotona princeps) during surveys from the Great Basin region in 1994–1999 and 2003–2008 differed between the two periods. Additionally, we tested whether various modeled aspects of ecohydrology better predicted relative density than did average annual precipitation, and whether risk of site-wide extirpation predicted subsequent population counts of pikas. We observed several patterns of change in pika abundance at range edges that likely constitute early warnings of distributional shifts. Predictors of pika abundance differed strongly between the survey periods, as did pika extirpation patterns previously reported from this region. Additionally, maximum snowpack and growing-season precipitation resulted in better-supported models than those using average annual precipitation, and constituted two of the top three predictors of pika density in the 2000s surveys (affecting pikas perhaps via vegetation). Unexpectedly, we found that extirpation risk positively predicted subsequent population size. Our results emphasize the need to clarify mechanisms underlying biotic responses to recent climate change at organism-relevant scales, to inform management and conservation strategies for species of concern.

  13. 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.

  14. Functional Evolution of Leptin of Ochotona curzoniae in Adaptive Thermogenesis Driven by Cold Environmental Stress

    Science.gov (United States)

    Yang, Jie; Bromage, Timothy G.; Zhao, Qian; Xu, Bao Hong; Gao, Wei Li; Tian, Hui Fang; Tang, Hui Jun; Liu, Dian Wu; Zhao, Xin Quan

    2011-01-01

    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. PMID:21698227

  15. Strategy formation in changing environment / Sven Heil

    Index Scriptorium Estoniae

    Heil, Sven

    2005-01-01

    Uuringu telekommunikatsiooni operaatori juhtimise kohta Eestis aastatel 1993-2003 tulemustest selgus, et ettevõtte üleminekul konkurentsiga turule muutus firma strateegia pika-ajalisest ette planeeritavast lühiajaliselt kujundatavaks

  16. Uued lambid hoiavad kokku energiat / Ferran Tarradellas Espuny

    Index Scriptorium Estoniae

    Tarradellas Espuny, Ferran

    2009-01-01

    Hõõglampide kasutamise järk-järguline asendamine pika kasutusajaga kompaktlampide (säästupirnide) ja uue põlvkonna halogeen-hõõglampidega toob kaasa vastavalt 75 ning kuni 50 protsenti elektrienergia kokkuhoidu

  17. Strategy formation in changing environment / Sven Heil

    Index Scriptorium Estoniae

    Heil, Sven

    2005-01-01

    Uuringu telekommunikatsiooni operaatori juhtimise kohta Eestis aastatel 1993-2003 tulemustest selgus, et ettevõtte üleminekul konkurentsiga turule muutus firma strateegia pika-ajalisest ette planeeritavast lühiajaliselt kujundatavaks

  18. Sem prioritetov Tallinna

    Index Scriptorium Estoniae

    2003-01-01

    Tallinna linnakantselei Eurointegratsioonibüroo juhataja Hedi Pika, projektijuhi Tõnu Karu ja Tallinna alalise esindaja Brüsselis Kaido Sireli tööst Euroopa Liidu struktuurifondide projektide realiseerimisel

  19. Applying theory of constraints in tactical and strategic management / Kalev Kaarna, Mait Miljan

    Index Scriptorium Estoniae

    Kaarna, Kalev

    2002-01-01

    Bibliogr. lk. 86-87. - Kokkuvõte eesti keeles lk. 87. Piirangute teooria kasutamise vajadusest ja võimalustest. Piirangute juhtimisest pikas perspektiivis ning sellel põhinevast strateegilisest juhtimisest. Tabelid

  20. Applying theory of constraints in tactical and strategic management / Kalev Kaarna, Mait Miljan

    Index Scriptorium Estoniae

    Kaarna, Kalev

    2002-01-01

    Bibliogr. lk. 86-87. - Kokkuvõte eesti keeles lk. 87. Piirangute teooria kasutamise vajadusest ja võimalustest. Piirangute juhtimisest pikas perspektiivis ning sellel põhinevast strateegilisest juhtimisest. Tabelid

  1. Avaliku sektori kinnisvaraalase haldussuutlikkuse tagamine / Janno Reiljan

    Index Scriptorium Estoniae

    Reiljan, Janno, 1951-

    2007-01-01

    Analüüsitakse avaliku sektori kinnisvarapoliitika aluseid ja kinnisvarategevuse juhtimist, kaalutakse rentimise ja omamise poolt- ja vastuargumente ning jõutakse järeldusele, et pikas perspektiivis on kinnisvara omamine kasulikum kui rentimine

  2. Ground Wave Emergency Network Final Operational Capability: Environmental Assessment for Central Utah Relay Node, Site Number RN 8C920UT

    Science.gov (United States)

    1993-04-16

    white strobe light at the top, which emits 40 flashes per minute and is rated at 20,000 candelas for daytime and twilight use and 2,000 candelas for...lynx Felix lynx canadensis North American wolverine Gulo gulo luscus Wasatch pika Ochotona princeps wasatchensis Heliotrope pika Ochotona princeps...free oxygen Aquifer A water-bearing stratum of permeable rock, sand, or gravel D-5 Candela A unit of meastre of the in.ensity of light eoual to the

  3. Testis-specific lactate dehydrogenase is expressed in somatic tissues of plateau pikas☆

    Science.gov (United States)

    Wang, Duowei; Wei, Lian; Wei, Dengbang; Rao, Xinfeng; Qi, Xinzhang; Wang, Xiaojun; Ma, Benyuan

    2013-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the interconversion of pyruvate with lactate. In mammals the, Ldh-c gene was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), belonging to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living at 3000–5000 m above sea levelon the Qinghai-Tibet Plateau. We found that the expression pattern of six LDH isoenzymes in the somatic tissues of female and male plateau pikas to be the same as those in testis and sperm, suggesting that LDH-C4 was expressed in somatic tissues of plateau pika. Here we report the detection of LDHC in the somatic tissues of plateau pika using RT-PCR, Western blotting and immunohistochemistry. Our results indicate that Ldh-c mRNA is transcribed in the heart, liver, lung, kidney, brain, skeletal muscle and testis. In somatic tissues LDHC was translated in the cytoplasm, while in testis it was expressed in both cytoplasm and mitochondria. The third band from cathode to anode in LDH isoenzymes was identified as LDH-C4. The finding that Ldh-c is expressed in both somatic tissues and testis of plateau pika provides important implications for more in-depth research into the Ldh-c function in mammals. PMID:23772382

  4. Testing alternative models of climate-mediated extirpations

    Science.gov (United States)

    Beever, E.A.; Chris, R.A.Y.; Mote, P.W.; Wilkening, J.L.

    2010-01-01

    Biotic responses to climate change will vary among taxa and across latitudes, elevational gradients, and degrees of insularity. However, due to factors such as phenotypic plasticity, ecotypic variation, and evolved tolerance to thermal stress, it remains poorly understood whether losses should be greatest in populations experiencing the greatest climatic change or living in places where the prevailing climate is closest to the edge of the species' bioclimatic envelope (e.g., at the hottest, driest sites). Research on American pikas (Ochotona princeps) in montane areas of the Great Basin during 1994-1999 suggested that 20th-century population extirpations were predicted by a combination of biogeographic, anthropogenic, and especially climatic factors. Surveys during 2005-2007 documented additional extirpations and within-site shifts of pika distributions at remaining sites. To evaluate the evidence in support of alternative hypotheses involving effects of thermal stress on pikas, we placed temperature sensors at 156 locations within pika habitats in the vicinity of 25 sites with historical records of pikas in the Basin. We related these time series of sensor data to data on ambient temperature from weather stations within the Historical Climate Network. We then used these highly correlated relationships, combined with long-term data from the same weather stations, to hindcast temperatures within pika habitats from 1945 through 2006. To explain patterns of loss, we posited three alternative classes of direct thermal stress: (1) acute cold stress (number of days below a threshold temperature); (2) acute heat stress (number of days above a threshold, temperature); and. (3) chronic heat stress (average summer temperature). Climate change was defined as change in our thermal metrics between two 31-y.r periods: 1945-1975 and 1976-2006. We found that patterns of persistence were well predicted by metrics of climate. Our best models suggest some effects of climate change

  5. Distribution of a climate-sensitive species at an interior range margin

    Science.gov (United States)

    Ray, Chris; Beever, Erik; Rodhouse, Thomas J.

    2016-01-01

    Advances in understanding the factors that limit a species’ range, particularly in the context of climate change, have come disproportionately through investigations at range edges or margins. The margins of a species’ range might often correspond with anomalous microclimates that confer habitat suitability where the species would otherwise fail to persist. We addressed this hypothesis using data from an interior, climatic range margin of the American pika (Ochotona princeps), an indicator of relatively cool, mesic climates in rocky habitats of western North America. Pikas in Lava Beds National Monument, northeastern California, USA, occur at elevations much lower than predicted by latitude and longitude. We hypothesized that pika occurrence within Lava Beds would be associated primarily with features such as “ice caves” in which sub-surface ice persists outside the winter months. We used data loggers to monitor sub-surface temperatures at cave entrances and at non-cave sites, confirming that temperatures were cooler and more stable at cave entrances. We surveyed habitat characteristics and evidence of pika occupancy across a random sample of cave and non-cave sites over a 2-yr period. Pika detection probability was high (~0.97), and the combined occupancy of cave and non-cave sites varied across the 2 yr from 27% to 69%. Contrary to our hypothesis, occupancy was not higher at cave sites. Vegetation metrics were the best predictors of site use by pikas, followed by an edge effect and elevation. The importance of vegetation as a predictor of pika distribution at this interior range margin is congruent with recent studies from other portions of the species’ range. However, we caution that vegetation composition depends on microclimate, which might be the proximal driver of pika distribution. The microclimates available in non-cave crevices accessible to small animals have not been characterized adequately for lava landscapes. We advocate innovation in the

  6. Stalkerid jagatud

    Index Scriptorium Estoniae

    2010-01-01

    Eesti ulmeauhinna Stalker võitjad 2010. a. Parim tõlkeromaan: Charles Stross "Accelerando" (tõlkija Iris Jeletski), parim antoloogia või kogumik: "Munk maailma äärel. Vene ulmeantoloogia" (koostaja Arvi Nikkarev), parim tõlkejutt: Charles Stross "Poiss ja tema jumal" (antoloogiast "Täheaeg. Pika talve algus", tõlkija Sash Uusjärv), parim eesti romaan: Leo Kunnas "Gort Ashryn. II osa : Sõda", parin eesti autori jutt: Indrek Hargla "Doanizarre udulaam" (antoloogia "Täheaeg. Pika talve algus")

  7. Stalkerid jagatud

    Index Scriptorium Estoniae

    2010-01-01

    Eesti ulmeauhinna Stalker võitjad 2010. a. Parim tõlkeromaan: Charles Stross "Accelerando" (tõlkija Iris Jeletski), parim antoloogia või kogumik: "Munk maailma äärel. Vene ulmeantoloogia" (koostaja Arvi Nikkarev), parim tõlkejutt: Charles Stross "Poiss ja tema jumal" (antoloogiast "Täheaeg. Pika talve algus", tõlkija Sash Uusjärv), parim eesti romaan: Leo Kunnas "Gort Ashryn. II osa : Sõda", parin eesti autori jutt: Indrek Hargla "Doanizarre udulaam" (antoloogia "Täheaeg. Pika talve algus")

  8. Testis-Specific Lactate Dehydrogenase (LDH-C4) in Skeletal Muscle Enhances a Pika’s Sprint-Running Capacity in Hypoxic Environment

    Science.gov (United States)

    Wang, Yang; Wei, Lian; Wei, Dengbang; Li, Xiao; Xu, Lina; Wei, Linna

    2015-01-01

    LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae), which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in Qinghai

  9. Testis-Specific Lactate Dehydrogenase (LDH-C4 in Skeletal Muscle Enhances Apika’s Sprint-Running Capacity in Hypoxic Environment

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-08-01

    Full Text Available LDH-C4 is a lactate dehydrogenase that catalyzes the conversion of pyruvate to lactate. In mammals, ldh-c was originally thought to be expressed only in testis and spermatozoa. Plateau pika (Ochotona curzoniae, which belongs to the genus Ochotona of the Ochotonidea family, is a hypoxia tolerant mammal living 3000–5000 m above sea level on the Qinghai-Tibet Plateau, an environment which is strongly hypoxic. Ldh-c is expressed not only in testis and sperm but also in somatic tissues of plateau pika. In this study, the effects of N-propyl oxamate and N-isopropyl oxamate on LDH isozyme kinetics were compared to screens for a selective inhibitor of LDH-C4. To reveal the role and physiological mechanism of LDH-C4 in skeletal muscle of plateau pika, we investigated the effect of N-isopropyl oxamate on the pika exercise tolerance as well as the physiological mechanism. Our results show that Ki of N-propyl oxamate and N-isopropyl oxamate for LDH-A4, LDH-B4, and LDH-C4 were 0.094 mmol/L and 0.462 mmol/L, 0.119 mmol/L and 0.248 mmol/L, and 0.015 mmol/L and 0.013 mmol/L, respectively. N-isopropyl oxamate is a powerful selective inhibitor of plateau pika LDH-C4. In our exercise tolerance experiment, groups treated with inhibitors had significantly lower swimming times than the uninhibited control group. The inhibition rates of LDH, LD, and ATP were 37.12%, 66.27%, and 32.42%, respectively. Our results suggested that ldh-c is expressed in the skeletal muscle of plateau pika, and at least 32.42% of ATP in the skeletal muscle is catalyzed by LDH-C4 by anaerobic glycolysis. This suggests that pika has reduced dependence on oxygen and enhanced adaptation to hypoxic environment due to increased anaerobic glycolysis by LDH-C4 in skeletal muscle. LDH-C4 in plateau pika plays the crucial role in anaerobic glycolysis and generates ATP rapidly since this is the role of LDH-A4 in most species on plain land, which provide evidence that the native humans and animals in

  10. Liigne optimism Venemaa suhtes on põhjendamatu / Tõnis Oja

    Index Scriptorium Estoniae

    Oja, Tõnis, 1957-

    2008-01-01

    Paljud analüütikud ja investorid näevad Vene börsil häid hindu ja teenimisvõimalusi, kuid pikas perspektiivis on liigne optimism Venemaa aktsiaturgude suhtes põhjendamatu. Diagrammid: Venemaa börsiindeks RTS; Hansa Venemaa aktsiafond kaotanud viiendiku investoritest

  11. Taavet võidab Koljati targalt tegutsedes / Costas Markides ; interv. Endrik Randoja

    Index Scriptorium Estoniae

    Markides, Costas

    2007-01-01

    London Business Schooli professor Costas Markides vastab küsimustele, mis puudutavad tema raamatus "Fast Second" esitatud väidet, mille kohaselt esimesena uuele turule tulnud ettevõttest saab harva pikas perspektiivis turuliider, kuid samas on edukad just teisena turule sisenevad ettevõtted

  12. Ignar Fjuk tõi Pärnusse kunagise võistlustöö / Ester Vilgats

    Index Scriptorium Estoniae

    Vilgats, Ester

    2001-01-01

    Ignar Fjuki, Ferdinand Mälli ja Alar Oruvee 1978. a. valminud Pärnu kesklinna rekonstrueerimise arhitektuurivõistluse tööst, mis nägi ette Pärnus tollase Lenini allee, praeguse Pika tänava kitsendamist

  13. Ettepanekud : Pärnu, 12. mai 2010 = Proposals : Pärnu, 12 May 2010

    Index Scriptorium Estoniae

    2011-01-01

    Pärnu linnafoorumil tehtud ettepanekud. Pika tänava eri pooltele jääva kahe linnakeskuse ruumiline ja funktsionaane sidumine, vanalinna ühendamine uue keskuse ja jõega, linnaliiklus, jõeäärse ala kujundamine jm.

  14. [Heinz von zur Mühlen. Auf den Spuren einiger revlaer Firmen und Familien] / Paul Kaegbein

    Index Scriptorium Estoniae

    Kaegbein, Paul

    2007-01-01

    Arvustus: Heinz von zur Mühlen. Auf den Spuren einiger revlaer Firmen und Familien. In : Buch und Bildung im Baltikum. Münster : LIT, 2005, lk. 527-541. Pika tänava majade omanikest alates 17. sajandist - perekonnad Koch, Meyer, Kluge, Ströhm, Wassermann, Glehn, Eggers, Koppelson, Weiss. Nii loob autor pildi Tallinna "firmade ajaloost"

  15. Kawe Plaza. Pärnu mnt. 15/Tatari 2, Tallinn / Piret Lindpere

    Index Scriptorium Estoniae

    Lindpere, Piret, 1963-

    1998-01-01

    Kawe Plaza arhitektist Henno Sillastest. Sisekujundus: H. Sillaste, Kristiina Voolaid, ARS Interjöörprojekt. Peatöövõtt: AS EMV. Projekt 1993-1997, valmis 1998. Lainja klaasfasaadiga pika ja kitsa ärihoone lahenduse tingis krundi kolmnurkne kuju. Maja on sobitatud teiste väljakut moodustavate hoonetega. Tagafassaad on graniidist.

  16. Rabbits, refuges and resources : how foraging of herbivores is affected by living in burrows

    NARCIS (Netherlands)

    Dekker, J.J.A.

    2007-01-01

    Small herbivores such as rabbits, pika and marmots create spatial patterns in vegetation around their burrows by grazing. This PhD thesis focuses on these refuge-living herbivores.By performing experiments with rabbits, he showed that looking for predators causes the spatial patter

  17. Elektrijaam kütab kirgi ja ujutab Anija valla maid üle / Anneli Ammas

    Index Scriptorium Estoniae

    Ammas, Anneli, 1962-

    2004-01-01

    Uus Vetla hüdroelektrijaam ujutab üle ümbruskonna maid. Jõujaama omaniku Urmas Põllu sõnul ei oleks tammi veetaset allapoole lastes seal võimalik elektrit toota. Lisad: Hüdrojaama kasulikkus vaid sümboolne; Pika tasuvusega projekt

  18. My Video Collections / Marco Casagrande

    Index Scriptorium Estoniae

    Casagrande, Marco, 1971-

    2006-01-01

    Soome arhitekt ja kunstnik annab pika loendi oma videofilmide kollektsioonist, esitab subjektiivse filmide top 10-ne, mille esinumber on Andrei Tarkovski "Stalker". Teeb järelduse, et Tarkovski on talle kõige inspireerivam arhitekt, tema esitatud küsimused kõige suuremad

  19. Rabbits, refuges and resources : how foraging of herbivores is affected by living in burrows

    NARCIS (Netherlands)

    Dekker, J.J.A.

    2007-01-01

    Small herbivores such as rabbits, pika and marmots create spatial patterns in vegetation around their burrows by grazing. This PhD thesis focuses on these refuge-living herbivores.By performing experiments with rabbits, he showed that looking for predators causes the spatial

  20. Maarotist sai kirglik surfar / Anneli Ammas

    Index Scriptorium Estoniae

    Ammas, Anneli, 1962-

    2016-01-01

    Eesti-Ukraina verd Boris Ljubtšenkost, kes läheb 20. augustil oma 25. sünnipäeva hommikul Toompeale Pika Hermanni torni lippu heiskama. Boris Ljubtšenko kuulub ka Kaitseliitu ja õpetab Kaitseliidu lastelaagris surfamist

  1. Sõjategevus Eestis 17.-22. septembril 1944 / Toomas Hiio

    Index Scriptorium Estoniae

    Hiio, Toomas, 1965-

    2008-01-01

    Vägede paigutusest Eestis juuli lõpus 1944. Sakslaste taganemisest septembris. Punaarmee jõudmisest Tallinna. Kes heiskas esimesena punalipu Pika Hermanni torni? Tallinna hõivamise erinevatest kirjeldustest. Eesti sõjaväelaste vastupanust sakslastele taganemise ajal.

  2. Kawe Plaza. Pärnu mnt. 15/Tatari 2, Tallinn / Piret Lindpere

    Index Scriptorium Estoniae

    Lindpere, Piret, 1963-

    1998-01-01

    Kawe Plaza arhitektist Henno Sillastest. Sisekujundus: H. Sillaste, Kristiina Voolaid, ARS Interjöörprojekt. Peatöövõtt: AS EMV. Projekt 1993-1997, valmis 1998. Lainja klaasfasaadiga pika ja kitsa ärihoone lahenduse tingis krundi kolmnurkne kuju. Maja on sobitatud teiste väljakut moodustavate hoonetega. Tagafassaad on graniidist.

  3. My Video Collections / Marco Casagrande

    Index Scriptorium Estoniae

    Casagrande, Marco, 1971-

    2006-01-01

    Soome arhitekt ja kunstnik annab pika loendi oma videofilmide kollektsioonist, esitab subjektiivse filmide top 10-ne, mille esinumber on Andrei Tarkovski "Stalker". Teeb järelduse, et Tarkovski on talle kõige inspireerivam arhitekt, tema esitatud küsimused kõige suuremad

  4. Ettepanekud : Pärnu, 12. mai 2010 = Proposals : Pärnu, 12 May 2010

    Index Scriptorium Estoniae

    2011-01-01

    Pärnu linnafoorumil tehtud ettepanekud. Pika tänava eri pooltele jääva kahe linnakeskuse ruumiline ja funktsionaane sidumine, vanalinna ühendamine uue keskuse ja jõega, linnaliiklus, jõeäärse ala kujundamine jm.

  5. Bõvshii prezident Gruzii Eduard Shevardnadze : "V Gruzii oppozitsija slabaja." / Eduard Shevardnadze

    Index Scriptorium Estoniae

    Shevardnadze, Eduard

    2006-01-01

    Gruusia endine president vastab küsimustele, mida ta võiks nimetada oma peamiseks veaks pika poliitilise elu jooksul, mida peaks tegema Gruusia, et saada Abhaasia ja Lõuna-Osseetia tagasi rahulikul teel, millised on Gruusia ja Venemaa halbade suhete põhjused, kas Gruusia peaks minema Venemaa või lääne suunas

  6. Liigne optimism Venemaa suhtes on põhjendamatu / Tõnis Oja

    Index Scriptorium Estoniae

    Oja, Tõnis, 1957-

    2008-01-01

    Paljud analüütikud ja investorid näevad Vene börsil häid hindu ja teenimisvõimalusi, kuid pikas perspektiivis on liigne optimism Venemaa aktsiaturgude suhtes põhjendamatu. Diagrammid: Venemaa börsiindeks RTS; Hansa Venemaa aktsiafond kaotanud viiendiku investoritest

  7. The impact of isolation: evolutionary processes in Hoplitomeryx

    NARCIS (Netherlands)

    van der Geer, A.A.E.

    2014-01-01

    The Late Miocene palaeo-island of Gargano, today part of mainland southern Italy, was home to a strongly endemic, strongly disharmonic and depauperate fauna consisting entirely of deer-like ruminants, rodents, pikas, an otter and insectivores, besides reptiles, amphibians and a peculiar avifauna. Th

  8. [Heinz von zur Mühlen. Auf den Spuren einiger revlaer Firmen und Familien] / Paul Kaegbein

    Index Scriptorium Estoniae

    Kaegbein, Paul

    2007-01-01

    Arvustus: Heinz von zur Mühlen. Auf den Spuren einiger revlaer Firmen und Familien. In : Buch und Bildung im Baltikum. Münster : LIT, 2005, lk. 527-541. Pika tänava majade omanikest alates 17. sajandist - perekonnad Koch, Meyer, Kluge, Ströhm, Wassermann, Glehn, Eggers, Koppelson, Weiss. Nii loob autor pildi Tallinna "firmade ajaloost"

  9. Lõpetame raiskamise, mitte kulutamise / Peeter Kreitzberg

    Index Scriptorium Estoniae

    Kreitzberg, Peeter, 1948-2011

    2008-01-01

    Keerulisest majandusolukorrast välja tulemiseks tuleb lõpetada raiskamine, kuid mitte kulutamine. Autori sõnul põhjustab raiskamist alus- ja põhiharidusse piisavate kulutuste tegemata jätmine pika aja jooksul; raiskamist tähendab pisikestel omavalitsustel põhinev haldusstruktuur. Eesti vajab Riigikogu tulevikukomisjoni

  10. Eestlane kogeb õnne planeedi arvel / Liisi Poll

    Index Scriptorium Estoniae

    Poll, Liisi, 1980-

    2006-01-01

    Ühenduste New Economics Foundation (nef) ja Friends of Earth (FoE) tehtud uuring "Happy Planet Index" selgitas, millised riigid kasutavad oma kodanike pika ja õnneliku elu saavutamiseks kõige vähem maakera ressursse. Eesti on tabelis 173. kohal. Lisa: Õnnetu planeet

  11. Koolilaps sai oma toa / Tertit Linturi

    Index Scriptorium Estoniae

    Linturi, Tertit

    2003-01-01

    Endine kahe lapse magamistuba kujundati ümber koolimineva tütre omaette toaks, kus on koolilaud, kummut ja voodi, mille all on väljatõmmatavad sahtelkastid. Pika- ja kitsavõitu toa otsasein sai uue värvi. 4 ill

  12. Vene-Saksa gaasijuhe võib hakata kulgema läbi Eesti majandusvete / Ulvar Käärt

    Index Scriptorium Estoniae

    Käärt, Ulvar, 1982-

    2007-01-01

    Soome väitel on tema vetes merepõhi Vene-Saksa gaasijuhtme jaoks liiga ebatasane ja kivine. Gaasijuhtme rajamisega tegelev Nord Stream taotleb Eestilt luba uurida Eesti vete alust merepõhja. Lisa: Gaasitarned algavad 2010 läbi kahe 1200 km pika toru. Kaart: Vene-Saksa gaasijuhe. Kommenteerib Marko Mihkelson

  13. 95 päeva sõjatandril, päevik tagataskus / Leo Kunnas ; interv. Erkki Bahovski

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kolonelleitnant Leo Kunnas räägib Iraagi sissisõjast ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", mis põhineb tema Iraagi-kogemustel. Vt. samas: Sõda, kus eestlane on sisside vastu

  14. Viiv enne kojuminekut / Leo Kunnas ; interv. Helen Arak

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude Peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas oma perekonnast, lapsepõlvekodust Põlvamaal ja praegusest elamisest Tallinnas, missioonil viibivate sõjaväelaste probleemidest ning eluolust Iraagis. Lisa: Katkend Leo Kunnase raamatust "Viiv pikas sõjas"

  15. Hümni kaasajastamisest. Kui üldse midagi muuta, siis lauluteksti / Erik Tohvri

    Index Scriptorium Estoniae

    Tohvri, Erik, pseud., 1933-

    2008-01-01

    Eesti Meestelaulu Seltsi ettepanekust muuta Pika Hermanni tornis lipu langetamisel mängitavat signatuuri austamaks Ernesaksa, kelle 100. sünniaastapäeva 2008. aastal tähistatakse. "Mu isamaa armas" asendada motiiviga laulust "Mu isamaa on minu arm"

  16. Me õnn ja rõõm / Alo Lõhmus

    Index Scriptorium Estoniae

    Lõhmus, Alo

    2008-01-01

    Eesti Meestelaulu Seltsi ettepanekust muuta Pika Hermanni tornis lipu langetamisel mängitavat signatuuri austamaks Ernesaksa, kelle 100. sünniaastapäeva 2008. aastal tähistatakse. "Mu isamaa armas" asendada motiiviga laulust "Mu isamaa on minu arm"

  17. Habitat availability and gene flow influence diverging local population trajectories under scenarios of climate change: a place-based approach.

    Science.gov (United States)

    Schwalm, Donelle; Epps, Clinton W; Rodhouse, Thomas J; Monahan, William B; Castillo, Jessica A; Ray, Chris; Jeffress, Mackenzie R

    2016-04-01

    Ecological niche theory holds that species distributions are shaped by a large and complex suite of interacting factors. Species distribution models (SDMs) are increasingly used to describe species' niches and predict the effects of future environmental change, including climate change. Currently, SDMs often fail to capture the complexity of species' niches, resulting in predictions that are generally limited to climate-occupancy interactions. Here, we explore the potential impact of climate change on the American pika using a replicated place-based approach that incorporates climate, gene flow, habitat configuration, and microhabitat complexity into SDMs. Using contemporary presence-absence data from occupancy surveys, genetic data to infer connectivity between habitat patches, and 21 environmental niche variables, we built separate SDMs for pika populations inhabiting eight US National Park Service units representing the habitat and climatic breadth of the species across the western United States. We then predicted occurrence probability under current (1981-2010) and three future time periods (out to 2100). Occurrence probabilities and the relative importance of predictor variables varied widely among study areas, revealing important local-scale differences in the realized niche of the American pika. This variation resulted in diverse and - in some cases - highly divergent future potential occupancy patterns for pikas, ranging from complete extirpation in some study areas to stable occupancy patterns in others. Habitat composition and connectivity, which are rarely incorporated in SDM projections, were influential in predicting pika occupancy in all study areas and frequently outranked climate variables. Our findings illustrate the importance of a place-based approach to species distribution modeling that includes fine-scale factors when assessing current and future climate impacts on species' distributions, especially when predictions are intended to manage and

  18. Developing a protocol for long-term population monitoring and habitat projections for a climate-sensitive sentinel species to track ecosystem change and species range shifts

    Science.gov (United States)

    Beers, A.

    2016-12-01

    As a response to ongoing climate change, many species have started to shift their ranges poleward and toward higher elevations and mountain environments are predicted to experience especially rapid climatic changes. Because of this, there is likely a greater risk of habitat loss and local extinctions for species at high elevations compared to species at lower elevations. Among those potentially threatened habitat specialists is the American pika (Ochotona princeps), a climate sensitive indicator of climate change effects which may already be experiencing climate driven extirpations. Pikas are considered sentinels, indicators of greater ecosystem change. Changes in their distribution speaks to changes in availability of resources they require and shifts in the environment. Pika presence is closely tied to sub-surface ice features that act as a temperature buffer and water source. Those sub-surface ice features are critical in water cycling and long-term water storage and drive downstream hydrological and ecological processes. Understanding how this species responds to climate change therefore provides a model to inform landscape level conservation and management decisions. Pikas may be particularly vulnerable in parts of Colorado, including Rocky Mountain National Park (ROMO) and the Niwot Ridge LTER (NWT), where they may face population collapse as habitat suitability and connectivity both decline in response to various possible climate change scenarios, in large part because of cold stress and declining functional connectivity. Because of their potential role as an ecosystem indicator, their risk for decline, and how limitations to their survival likely vary across their range, management groups can use place based models of habitat suitability for pikas or other sentinel species in designing long term monitoring protocols to detect ecosystem responses to climate change. In this project we used remotely sensed data, occupancy surveys, and a random tessellation

  19. Nõmme maja "Kergus" : Kerese tn., Tallinn / Ülar Mark, Kalle Komissarov

    Index Scriptorium Estoniae

    Mark, Ülar

    1999-01-01

    Kahekorruselise, tänavapoolse pika umbse seinaga eramu projekteeris Arhitektuuribüroo Mark & Tamm, arhitekt Ülar Mark, kaasautor Kalle Komissarov. Konstruktiivne osa: Randväli & Karema Inseneribüroo. Projekt 1997, hoone valmis 1999. Eramu tähenduse ümbermõtestamisest. 13 illustratsiooni: korruste plaanid, välisvaated, sisevaade.Mark & Tamm (arhitektibüroo)

  20. Rabbits, refuges and resources : how foraging of herbivores is affected by living in burrows

    OpenAIRE

    Dekker, J.J.A.

    2007-01-01

    Small herbivores such as rabbits, pika and marmots create spatial patterns in vegetation around their burrows by grazing. This PhD thesis focuses on these refuge-living herbivores.By performing experiments with rabbits, he showed that looking for predators causes the spatial patterns: thiscostsmore foraging time as the burrow is farther, causing a preference for foraging close to the burrow. The animals can stay close to their burrow when the vegetation grows, but are forced to graze larger a...

  1. Nõmme maja "Kergus" : Kerese tn., Tallinn / Ülar Mark, Kalle Komissarov

    Index Scriptorium Estoniae

    Mark, Ülar

    1999-01-01

    Kahekorruselise, tänavapoolse pika umbse seinaga eramu projekteeris Arhitektuuribüroo Mark & Tamm, arhitekt Ülar Mark, kaasautor Kalle Komissarov. Konstruktiivne osa: Randväli & Karema Inseneribüroo. Projekt 1997, hoone valmis 1999. Eramu tähenduse ümbermõtestamisest. 13 illustratsiooni: korruste plaanid, välisvaated, sisevaade.Mark & Tamm (arhitektibüroo)

  2. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  3. Kahetsükliline kõrgharidus ehk 3+2 süsteem / Annika Tina

    Index Scriptorium Estoniae

    Tina, Annika

    Bologna protsessi üheks esmaseks tegevuseks oli pika õppetsükli lahutamine bakalaureuse- ja magistriõppeks ehk 3+2 süsteemiks. 2007. aastal oli 82% Euroopa kõrgkoolidest valinud Bologna protsessi eesmaärkidele vastava õppekavade süsteemi, Eesti läks üle 3+2 süsteemile 2002/2003 õppeaastal, tänaseks õpib Eestis uutel õppekavadel 90% kõrgkoolidest

  4. Rüütli-Luukase leppe konkreetseteks võitjateks saavad haridus ja noored / Mirko Ojakivi

    Index Scriptorium Estoniae

    Ojakivi, Mirko

    2003-01-01

    Ühiskondlikust leppest. Tartu Ülikooli rektori Jaak Aaviksoo, Keskerakonna juhatuse liikme Evelyn Sepp'a, Reformierakonna aseesimees Meelis Atoneni, Isamaliidu esimees Tunne Kelami ja Res Publica volikogu esimees Urmas Reinsalu kommentaarid. Samas: Kes võidavad leppest? ; Aadu Luukas: tänane on alles pika tee algus ; Keskerakond ütles lõplikult "ei" ; Ühiskondliku kokkuleppe teksti viimane versioon

  5. iPhone'i peab saama lukust lahti teha / Dannar Leitmaa

    Index Scriptorium Estoniae

    Leitmaa, Dannar, 1982-

    2008-01-01

    Kuigi Euroopa Liidu direktiivi kohaselt peab mobiiltelefoni omanikul olema võimalus telefoni lukustusest avada, näeb iPhone'i tootva Apple'i ärimudel ette iPhone'i ostmist ühelt operaatorilt. iPhone 3G telefonide ametlik maaletooja Eestis on EMT, kes pakub neid müügiks kahes erinevas hinnapaketis. Lisa: Juba öösel seisti pikas järjekorras

  6. iPhone'i peab saama lukust lahti teha / Dannar Leitmaa

    Index Scriptorium Estoniae

    Leitmaa, Dannar, 1982-

    2008-01-01

    Kuigi Euroopa Liidu direktiivi kohaselt peab mobiiltelefoni omanikul olema võimalus telefoni lukustusest avada, näeb iPhone'i tootva Apple'i ärimudel ette iPhone'i ostmist ühelt operaatorilt. iPhone 3G telefonide ametlik maaletooja Eestis on EMT, kes pakub neid müügiks kahes erinevas hinnapaketis. Lisa: Juba öösel seisti pikas järjekorras

  7. Leo Kunnas, sõdurjumala teener / Leo Kunnas ; interv. Eve Jaakson

    Index Scriptorium Estoniae

    Kunnas, Leo, 1967-

    2006-01-01

    Kaitsejõudude peastaabi operatiivosakonna ülem kolonelleitnant Leo Kunnas räägib Iraagi sõja kogemustest ja oma raamatust "Viiv pikas sõjas. Märkmeid Iraagi sõjast", riigikaitsest, kaitseväeteenistusest, kaitseminister Jürgen Ligist, kaitsepoliitikast, NATO-st, sõjalisest koostööst, perekonnast. Kommenteerivad Sten Reimann ja Venno Loosaar

  8. Kahetsükliline kõrgharidus ehk 3+2 süsteem / Annika Tina

    Index Scriptorium Estoniae

    Tina, Annika

    Bologna protsessi üheks esmaseks tegevuseks oli pika õppetsükli lahutamine bakalaureuse- ja magistriõppeks ehk 3+2 süsteemiks. 2007. aastal oli 82% Euroopa kõrgkoolidest valinud Bologna protsessi eesmaärkidele vastava õppekavade süsteemi, Eesti läks üle 3+2 süsteemile 2002/2003 õppeaastal, tänaseks õpib Eestis uutel õppekavadel 90% kõrgkoolidest

  9. Limb bone morphology, bone strength, and cursoriality in lagomorphs.

    Science.gov (United States)

    Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

    2014-10-01

    The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which 'cursorial specialization' affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high 'displacement advantage', permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing

  10. Optimized data flow for the waste form documentation of compactable radioactive wastes; Optimierter Datenfluss zur Erstellung von Abfallgebindedokumentationen fuer pressbare radioaktive Abfaelle

    Energy Technology Data Exchange (ETDEWEB)

    Lange, M. [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany); Risch, R. [WTI Wissenschaftlich-Technische Ingenieurleistung GmbH, Juelich (Germany)

    2010-05-15

    According to the national radiation protection regulations (Strahlenschutzverordnung)it is necessary to perform a detailed documentation on radioactive materials, including the waste flow, transport and storage. The book-keeping system AVK is an authorized data base system. The authors describe the data relevant sheets, the activity calculation procedure based on local dose rate measurements and gamma spectroscopy and the necessary documents for the licensing procedure. For a structured and efficient waste form documentation a data base (PIKA-AS: project information and control system) was developed by GNS that includes all documentation relevant data from different measuring and calculation activities.

  11. Ränk tee rehepaplusest talupojamõistuseni / Andres Herkel

    Index Scriptorium Estoniae

    Herkel, Andres, 1962-

    2008-01-01

    Parlamendiliikme sõnul ei pruugi majanduslangus tähendada otsest ja kiiret väärtushinnangute muutumist, küll aga võib see kaasa tuua nii poliitiliste kui isiklike otsuste rea, mis pikas perspektiivis tagab Eestile kindlama ja stabiilsema arengu. Ilmunud ka: Meie Maa 5. november lk. 2; Sõnumitooja 5. nov. lk. 2; Harju Ekspress 7. nov. lk. 8; Koit 6. nov. lk. 6; Kuulutaja 7. nov. lk. 4; Elva Postipoiss 8. nov. lk. 4; Lõunaleht 20. nov. lk. 4

  12. Evolutionary Insights into IL17A in Lagomorphs

    Directory of Open Access Journals (Sweden)

    Fabiana Neves

    2015-01-01

    Full Text Available In leporids, IL17A had been implicated in the host defense against extracellular pathogens, such as Francisella tularensis that infects hares and rabbits and causes the zoonotic disease tularemia. Here, we studied IL17A from five lagomorphs, European rabbit, pygmy rabbit, brush rabbit, European brown hare, and American pika. We observed that this protein is highly conserved between these species, with a similarity of 97–99% in leporids and ~88% between leporids and American pika. The exon/intron structure, N-glycosylation sites, and cysteine residues are conserved between lagomorphs. However, at codon 88, one of the interaction sites between IL17A and its receptor IL17RA, there is an Arg>Pro mutation that only occurs in European rabbit and European brown hare. This could induce critical alterations in the IL17A structure and conformation and consequently modify its function. The differences observed between leporids and humans or rodents might also represent important alterations in protein structure and function. In addition, as for other interleukins, IL17A sequences of human and European rabbit are more closely related than the sequences of human and mouse or European rabbit and mouse. This study gives further support to the hypothesis that European rabbit might be a more suitable animal model for studies on human IL17.

  13. A noninvasive hair sampling technique to obtain high quality DNA from elusive small mammals.

    Science.gov (United States)

    Henry, Philippe; Henry, Alison; Russello, Michael A

    2011-03-13

    Noninvasive genetic sampling approaches are becoming increasingly important to study wildlife populations. A number of studies have reported using noninvasive sampling techniques to investigate population genetics and demography of wild populations. This approach has proven to be especially useful when dealing with rare or elusive species. While a number of these methods have been developed to sample hair, feces and other biological material from carnivores and medium-sized mammals, they have largely remained untested in elusive small mammals. In this video, we present a novel, inexpensive and noninvasive hair snare targeted at an elusive small mammal, the American pika (Ochotona princeps). We describe the general set-up of the hair snare, which consists of strips of packing tape arranged in a web-like fashion and placed along travelling routes in the pikas' habitat. We illustrate the efficiency of the snare at collecting a large quantity of hair that can then be collected and brought back to the lab. We then demonstrate the use of the DNA IQ system (Promega) to isolate DNA and showcase the utility of this method to amplify commonly used molecular markers including nuclear microsatellites, amplified fragment length polymorphisms (AFLPs), mitochondrial sequences (800bp) as well as a molecular sexing marker. Overall, we demonstrate the utility of this novel noninvasive hair snare as a sampling technique for wildlife population biologists. We anticipate that this approach will be applicable to a variety of small mammals, opening up areas of investigation within natural populations, while minimizing impact to study organisms.

  14. 高原鼠兔扰动对高寒草地植物群落特征的影响%Impacts of Ochotona pallasi disturbance on alpine grassland community characteristics

    Institute of Scientific and Technical Information of China (English)

    赵国琴; 李广泳; 马文虎; 赵殿智; 李小雁

    2013-01-01

    Plateau pika is the main fossorial mammal in the alpine grassland in Qinghai Lake Watershed of Northwest China.Based on the field investigation data from 18 alpine grassland quadrats in the Watershed,and by using redundancy analysis (RDA) and the surface fitting offered by ‘ R-Vegan',the disturbance intensity of plateau pika (Ochotona pallasi) was classified as four levels.In order to explore the impacts of plateau pika disturbance on the alpine grassland ecosystem and its grazing quality,the community characteristics under different disturbance intensities by plateau pika were analyzed,and a conceptual model about the alpine grassland community succession was proposed.The results showed that with the increase of the disturbance intensity,the dominant species changed from Juncus roemerianus to Poa pratensis and Laux maritima.When the disturbance was small,the community had high quantitative values of coverage,aboveground biomass,biodiversity,and species richness,but the proportion of weeds was also high.When the disturbance was large,the quantitative values were the lowest,while the proportion of weeds was the highest.When the disturbance was moderate,the community had relatively high quantitative values,and the proportion of grasses and sedges was the highest.It was concluded that the community's characteristic values under low plateau pika disturbance intensity were high but the grazing quality was low,while high disturbance intensity resulted in the grassland degradation.Therefore,the disturbance intensity in the threshold could maintain the stability of alpine grassland ecosystem and improve its grazing quality.%高原鼠兔是青海湖流域高寒草地主要的啮齿动物.本文基于R-Vegan中的RDA排序方法,以有效洞口数差异将高原鼠兔扰动强度划分为4组,分析不同扰动强度下高寒草地植物群落特征,进而提出群落演替的概念模型,探究高原鼠兔扰动对高寒草地生态系统及放牧质量的影响.结果

  15. Sierra Nevada Rock Glaciers: Biodiversity Refugia in a Warming World?

    Science.gov (United States)

    Millar, C. I.; Westfall, R. D.

    2007-12-01

    also mapped 125 discrete locations of American pika (Ochotona princeps) and found a strong association of pika presence with active and relict RIFs, in particular cirque rock glaciers, valley rock glaciers, and boulder streams. Using the PRISM climate model and a small network of temperature dataloggers from RIF habitats, we present a climate envelope for the pika habitats we surveyed. We propose that the large area of RIFs in the Sierra Nevada over a range of elevations could provide extensive habitat for pika in the warming future. RIFs in general are a group of landforms little studied in high mountains of western North America but of potential increasing importance to hydrologic and ecologic function as climate warms in the future. Millar, C.I. and R.D. Westfall. In press. Rock glaciers and periglacial rock-ice features in the Sierra Nevada; Classification, distribution, and climate relationships. Quaternary International.

  16. Draft genome sequence of the Tibetan antelope.

    Science.gov (United States)

    Ge, Ri-Li; Cai, Qingle; Shen, Yong-Yi; San, A; Ma, Lan; Zhang, Yong; Yi, Xin; Chen, Yan; Yang, Lingfeng; Huang, Ying; He, Rongjun; Hui, Yuanyuan; Hao, Meirong; Li, Yue; Wang, Bo; Ou, Xiaohua; Xu, Jiaohui; Zhang, Yongfen; Wu, Kui; Geng, Chunyu; Zhou, Weiping; Zhou, Taicheng; Irwin, David M; Yang, Yingzhong; Ying, Liu; Bao, Haihua; Kim, Jaebum; Larkin, Denis M; Ma, Jian; Lewin, Harris A; Xing, Jinchuan; Platt, Roy N; Ray, David A; Auvil, Loretta; Capitanu, Boris; Zhang, Xiufeng; Zhang, Guojie; Murphy, Robert W; Wang, Jun; Zhang, Ya-Ping; Wang, Jian

    2013-01-01

    The Tibetan antelope (Pantholops hodgsonii) is endemic to the extremely inhospitable high-altitude environment of the Qinghai-Tibetan Plateau, a region that has a low partial pressure of oxygen and high ultraviolet radiation. Here we generate a draft genome of this artiodactyl and use it to detect the potential genetic bases of highland adaptation. Compared with other plain-dwelling mammals, the genome of the Tibetan antelope shows signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission. Both the highland American pika, and the Tibetan antelope have signals of positive selection for genes involved in DNA repair and the production of ATPase. Genes associated with hypoxia seem to have experienced convergent evolution. Thus, our study suggests that common genetic mechanisms might have been utilized to enable high-altitude adaptation.

  17. [A NATURAL PLAGUE FOCUS. IN GORNYI ALTAI: FORMATION, DEVELOPMENT, AND FUNCTIONING].

    Science.gov (United States)

    Korzun, V M; Balakhoiov, S V; Chpanin, E V; Denisov, A V; Mikhailov, E P; Mischenko, A J; Yarygina, M B; Rozhdestvensky, E N; Fomina, L A

    2016-01-01

    The paper gives the results of analyzing the data of long-term studies of the natural focal pattern of plague in the Gornyi Altai natural focus. It describes a wide range of biological processes occurring in the focus and shows the most important patterns of its functioning as a complex multilevel ecological system. The key features of the formation of the focus have been revealed. The plague focus in South-Western Altai has formed relatively, recently, about half a century ago, then it has intensively developed and its enzootic area and the activity of epizootic manifestations have considerably increased. This process is due to the space-time transformations of the basic ecological and population characteristics of Pallas' pika (Ochotoma pallasi), the principal vector of the pathogen of plague and fleas parasitizing the mammal, which is in turn related to the aridization of mountain steppes in South-Western Altai.

  18. [Macro- and microevolution as related to the problem of origin and global expansion of the plague pathogen Yersinia pestis].

    Science.gov (United States)

    Suntsov, V V; Suntsova, N I

    2008-01-01

    The ratio of macro- and microevolutionary processes is considered with reference to the ecological scenario of the origin of the plague pathogen and its subsequent natural and anthropogenic global expansion. The macroevolutionary transformation of the ancestral pseudotuberculosis microbe clone into the initial plague microbe Yersinia pestis tarbagani occurred in Central Asia at the end of the Late Pleistocene by a "vertical" Darwinian way in an inadaptive heterothermal continual intermediate environment--the Mongolian marmot Marmota sibirica-flea Oropsylla silantiewi system--via a sequence of unstable and currently extinct intermediate forms. Its natural geographic expansion on the "oil spot" principle in the postglacial time led to the microevolutionary formation of 20-30 hostal subspecies circulating in populations of the background species of burrowing rodents and pikas in arid areas of Eurasia. The intercontinental spread of the "marmot" and "rat" pathogen subspecies in the past few centuries has been exclusively anthropogenic, with the involvement of synanthropic (ship) rats.

  19. Expertly validated models and phylogenetically-controlled analysis suggests responses to climate change are related to species traits in the order lagomorpha.

    Directory of Open Access Journals (Sweden)

    Katie Leach

    Full Text Available Climate change during the past five decades has impacted significantly on natural ecosystems, and the rate of current climate change is of great concern among conservation biologists. Species Distribution Models (SDMs have been used widely to project changes in species' bioclimatic envelopes under future climate scenarios. Here, we aimed to advance this technique by assessing future changes in the bioclimatic envelopes of an entire mammalian order, the Lagomorpha, using a novel framework for model validation based jointly on subjective expert evaluation and objective model evaluation statistics. SDMs were built using climatic, topographical, and habitat variables for all 87 lagomorph species under past and current climate scenarios. Expert evaluation and Kappa values were used to validate past and current models and only those deemed 'modellable' within our framework were projected under future climate scenarios (58 species. Phylogenetically-controlled regressions were used to test whether species traits correlated with predicted responses to climate change. Climate change is likely to impact more than two-thirds of lagomorph species, with leporids (rabbits, hares, and jackrabbits likely to undertake poleward shifts with little overall change in range extent, whilst pikas are likely to show extreme shifts to higher altitudes associated with marked range declines, including the likely extinction of Kozlov's Pika (Ochotona koslowi. Smaller-bodied species were more likely to exhibit range contractions and elevational increases, but showing little poleward movement, and fecund species were more likely to shift latitudinally and elevationally. Our results suggest that species traits may be important indicators of future climate change and we believe multi-species approaches, as demonstrated here, are likely to lead to more effective mitigation measures and conservation management. We strongly advocate studies minimising data gaps in our knowledge of

  20. Late Quaternary environments and biogeography in the Great Basin

    Science.gov (United States)

    Thompson, R. S.; Mead, J. I.

    1982-01-01

    Plant and animal remains found in packrat ( Neotoma spp.) middens and cave fill from the eastern and southern Great Basin region reveal the presence of subalpine conifers and boreal mammals at relatively low elevations during the Late Wisconsin. Limber pine ( Pinus flexilis) and bristlecone pine ( P. longaeva) were important in the late Pleistocene plant communities throughout this region. Spruce ( Picea cf. engelmannii) and common juniper ( Juniperus communis) were present in some of the more northerly localities, and Douglas fir ( Pseudotsuga menziesii) and white fir ( Abies concolor) were present in southern and eastern localities. Single needle pinyon pine ( Pinus monophylla), common across this region today, was apparently not present north of the Sheep Range of southern Nevada during the Late Wisconsin. Pikas ( Ochotona cf. princeps), small boreal mammals present in only a few Great Basin mountain ranges today, were common throughout the region. Heather voles ( Phenacomys cf. intermedius) have been found in two cave fill deposits in Nevada, though they are unknown in the Great Basin today. Limber and bristlecone pines are generally restricted to rocky substrates in modern subalpine habitats in the Great Basin, and this may also have been the case when these plants grew at lower elevations during the Late Wisconsin. Subalpine conifers were present on the rock outcrops sampled by the packrat middens, but shrub communities, perhaps dominated by sagebrush ( Artemisia spp.), may have been present on alluvial valley-bottom substrates. Forested habitats would thus have been isolated habitat islands, as they are today. Boreal small mammals, including pikas and heather voles, were able to colonize the Great Basin mountain ranges during the late Pleistocene. We suggest that these mammals were able to survive in the intervening valley-bottoms under a cool-summer climatic regime, and that continuous forest or woodland corridors were not necessary for migration.

  1. 阿尔金山国家级自然保护区食肉鸟兽调查%Survey on Carnivore Birds and Mammals in Altun Mountain National Natural Reserve

    Institute of Scientific and Technical Information of China (English)

    李叶; 张翔; 时磊

    2012-01-01

    2011-2012年,对阿尔金山国家级自然保护区的鼠类天敌——食肉鸟兽开展专项调查.通过调查,初步查明了保护区内共分布有鼠类天敌27种,分属2纲3目7科17属,其中有国家一级保护动物5种,二级保护动物17种.赤狐为保护区首次记录物种.对主要天敌的种类、分布、食性和活动规律,以及对高原鼠兔防治的潜在作用进行了初步分析.藏狐和大鵟可以作为进一步开展天敌防治鼠害工作的目标物种.%A special investigation on carnivorous mammals and birds was carried out in the Altun Mountain National Nature Reserve in 2011-2012. Research found out total 27 kinds of predators on rodent pests belonging to 2 classes,3 orders,7 families,and 17 genera distributing in the protected areas. Among them there are 5 kinds of national first class protection animal and 17 kinds of national second class protection animal. The red fox(Vulpes vuLpes)was first recorded from this region. The first analysis was carried out on varieties,distribution,feeding habits and the patterns of the main natural enemies and the potential role in controlling plateau pika (Ochotona curzoniae) . Tibetan fox and Buzzard can be used as target species for a further natural enemies controlling pika project.

  2. Phylogenetic correlates of extinction risk in mammals: species in older lineages are not at greater risk.

    Science.gov (United States)

    Verde Arregoitia, Luis Darcy; Blomberg, Simon P; Fisher, Diana O

    2013-08-22

    Phylogenetic information is becoming a recognized basis for evaluating conservation priorities, but associations between extinction risk and properties of a phylogeny such as diversification rates and phylogenetic lineage ages remain unclear. Limited taxon-specific analyses suggest that species in older lineages are at greater risk. We calculate quantitative properties of the mammalian phylogeny and model extinction risk as an ordinal index based on International Union for Conservation of Nature Red List categories. We test for associations between lineage age, clade size, evolutionary distinctiveness and extinction risk for 3308 species of terrestrial mammals. We show no significant global or regional associations, and three significant relationships within taxonomic groups. Extinction risk increases for evolutionarily distinctive primates and decreases with lineage age when lemurs are excluded. Lagomorph species (rabbits, hares and pikas) that have more close relatives are less threatened. We examine the relationship between net diversification rates and extinction risk for 173 genera and find no pattern. We conclude that despite being under-represented in the frequency distribution of lineage ages, species in older, slower evolving and distinct lineages are not more threatened or extinction-prone. Their extinction, however, would represent a disproportionate loss of unique evolutionary history.

  3. Scientific Culture Measures: Challenges and New Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Cerezo, J.L.; Muñoz van den Eynde, A

    2016-07-01

    Since mid-twentieth century, efforts to promote scientific and technological development and engage the public in R&D process are increasing. Among those efforts, since the 1970s first in United States and then in United Kingdom and Europe, governments have funded surveys aimed at understanding the public attitudes toward science, scientists, and science policy. The Science and Engineering Indicators series of the National Science Foundation, or the European Community through its Special Eurobarometer on Europeans, science and technology, have shaped the research, measures and indicators of public understanding of science surveys. Examples are, at international level, surveys like Scientific Culture in IberoAmerican Countries (2009, FECYT-OEI-RICYT), or the International Study on Scientific Culture (2012, BBVA Foundation); and at national level, surveys like Social Perception of Science and Technology (2002-2014) series, or the recent Perception, Interest, Knowledge, and Actions (PIKA) Survey (2014), both funded by Spanish Government through its Spanish Foundation for Science and Technology (FECYT). (Author)

  4. Start of operation of the barrel measuring facility II-01. Implementation into operational processes; Inbetriebnahme der Fassmessanlage FAME II-01. Einbindung in die betrieblichen Ablaeufe

    Energy Technology Data Exchange (ETDEWEB)

    Buesing, B. [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany); Escher, M. [Wissenschaftlich-Technische Ingenieurberatung GmbH (WTI), Juelich (Germany)

    2013-07-01

    For the operation of the barrel measuring facility (FAME) II-01 a variety requirements to the measuring techniques were defined and tested in the frame of start-up. The used mechanical engineering and measuring technique complies with the state-of-the-art. Using the barrel measuring facility quality assured determinations of the dose rate and the nuclide-specific activity inventory were performed. For the evaluation of the gamma spectrometric measurements of FAME II-01 appropriately qualified personnel is available. The implementation of the facility in combination with the connection to the data base system PIK-AS and AVK it guaranteed that important data are available in real-time for the measuring process and the subsequent work steps. Besides this it is guaranteed that using the import/export functions relevant data are reviewed, supplemented and exchanged between the systems without transfer errors. The determined data of the dose rate and gamma spectrometric measurements allow an activity determination of the waste package with quality assurance and close to reality. Conservative assumptions in the frame of activity calculations for the later final disposal can be reduced. The automated operation of FAME allows also the reduction of radiation exposure of the personnel.

  5. Mu süda on mägedes : [luuletused] / Robert Burns ; tlk. Ralf Parve, Ants Oras, Urmas Tõnisson, Kullo Vende, Mart Mäger, Georg Eduard Luiga, Friedrich Reinhold Kreutzwald, Karl August Hermann, Johannes Vau, Lydia Koidula, Ado Grenzstein

    Index Scriptorium Estoniae

    Burns, Robert, 1759-1796

    2006-01-01

    Sisu: Mu süda on mägedes ; Hing mägises Shotis ; Mu isa oli farmer ; Künnipoiss ; Noor neiu vanal mehel ; Vana Rob Morris ; Meg veskilt ; Veski-Meg ; Willie pruulis õlut ; John Odratera ; Hägisele ; Shotlased, nüüd seiske kindlad! ; Invernessi neid ; Kuradi tants aktsiisiametnikuga ; Macphersoni hüvastijätt / tlk. Ralf Parve ; Macphersoni hüvastijätt / / tlk. Ants Oras ; Nii ja naa ; Hiirele ; Eleegia Peg Nicholsoni surma puhul ; Vaga Willie palve ; Epitaaf vagale Willièle ; Värsid poeet Fergussoni portree alla ; Lõikuskuu laul ; On kaldal kõrkjad reas ; Mu arm on nagu ruske roos ; Mu arm... ; Oo, mu arm on verev, verev roos ; Esimene suudlus lahkudes ; Mõte karmist saatusest ; Oh näeksin tühja nõmme peal ; Kui näeksin ; "Kui üksi olles näeksid, neid..." ; Käies pikas rohus ; Värsiread ; Mind naine tihti taob ; Rõõmus lesk ; Willie Wastleì naine ; Mul on naine ; John Anderson / tlk. Urmas Tõnisson ; Jaan Anderson / tlk. Karl August Hermann ; Sügiselaul ; Kündja ja lill ; Kodu ; Ometi ; Kõige kiuste ; Kui õis, mis õitseb heinamaal ; Põlev armastus ; Hans ja Krõõt : [luuletused]. Epigramme: Raamatukoi ; Impromptu ; Puudus. Ammustele aegadele : [luuletus]. Autori kohta eluloolisi andmeid lk. 179

  6. Mu süda on mägedes : [luuletused] / Robert Burns ; tlk. Ralf Parve, Ants Oras, Urmas Tõnisson, Kullo Vende, Mart Mäger, Georg Eduard Luiga, Friedrich Reinhold Kreutzwald, Karl August Hermann, Johannes Vau, Lydia Koidula, Ado Grenzstein

    Index Scriptorium Estoniae

    Burns, Robert, 1759-1796

    2006-01-01

    Sisu: Mu süda on mägedes ; Hing mägises Shotis ; Mu isa oli farmer ; Künnipoiss ; Noor neiu vanal mehel ; Vana Rob Morris ; Meg veskilt ; Veski-Meg ; Willie pruulis õlut ; John Odratera ; Hägisele ; Shotlased, nüüd seiske kindlad! ; Invernessi neid ; Kuradi tants aktsiisiametnikuga ; Macphersoni hüvastijätt / tlk. Ralf Parve ; Macphersoni hüvastijätt / / tlk. Ants Oras ; Nii ja naa ; Hiirele ; Eleegia Peg Nicholsoni surma puhul ; Vaga Willie palve ; Epitaaf vagale Willièle ; Värsid poeet Fergussoni portree alla ; Lõikuskuu laul ; On kaldal kõrkjad reas ; Mu arm on nagu ruske roos ; Mu arm... ; Oo, mu arm on verev, verev roos ; Esimene suudlus lahkudes ; Mõte karmist saatusest ; Oh näeksin tühja nõmme peal ; Kui näeksin ; "Kui üksi olles näeksid, neid..." ; Käies pikas rohus ; Värsiread ; Mind naine tihti taob ; Rõõmus lesk ; Willie Wastleì naine ; Mul on naine ; John Anderson / tlk. Urmas Tõnisson ; Jaan Anderson / tlk. Karl August Hermann ; Sügiselaul ; Kündja ja lill ; Kodu ; Ometi ; Kõige kiuste ; Kui õis, mis õitseb heinamaal ; Põlev armastus ; Hans ja Krõõt : [luuletused]. Epigramme: Raamatukoi ; Impromptu ; Puudus. Ammustele aegadele : [luuletus]. Autori kohta eluloolisi andmeid lk. 179

  7. Radiometric and Geometric Analysis of Hyperspectral Imagery Acquired from an Unmanned Aerial Vehicle

    Directory of Open Access Journals (Sweden)

    Nancy F. Glenn

    2012-09-01

    Full Text Available In the summer of 2010, an Unmanned Aerial Vehicle (UAV hyperspectral calibration and characterization experiment of the Resonon PIKA II imaging spectrometer was conducted at the US Department of Energy’s Idaho National Laboratory (INL UAV Research Park. The purpose of the experiment was to validate the radiometric calibration of the spectrometer and determine the georegistration accuracy achievable from the on-board global positioning system (GPS and inertial navigation sensors (INS under operational conditions. In order for low-cost hyperspectral systems to compete with larger systems flown on manned aircraft, they must be able to collect data suitable for quantitative scientific analysis. The results of the in-flight calibration experiment indicate an absolute average agreement of 96.3%, 93.7% and 85.7% for calibration tarps of 56%, 24%, and 2.5% reflectivity, respectively. The achieved planimetric accuracy was 4.6 m (based on RMSE with a flying height of 344 m above ground level (AGL.

  8. Two new species of Schizorchis (Cestoda: Anoplocephalidae) from leporids (Lagomorpha: Leporidae) in China.

    Science.gov (United States)

    Cai, Kuizheng; Bai, Jialin; Chen, Shien

    2012-10-01

    Four specimens of wild leporids, Lepus capensis Linnaeus, 1758, in Longde County, Ningxia Hui Autonomous Region (NXHAR), and 40 domestic rabbits, Oryctolagus cuniculus (Linnaeus, 1758) (20 from Xiji County, NXHAR, and 20 from Jingning County, Gansu Province) were examined for the presence of helminth parasites. Two new cestode species of Schizorchis Hansen, 1948 (Anoplocephalidae), were found: Schizorchis sinensis sp. n. from L. capensis and Schizorchis oryctolagi sp. n. from domestic rabbits. Schizorchis sinensis sp. n. is distinguished from all the species in the genus from pikas, Ochotona spp. (Lagomorpha: Ochotonidae) by having much longer strobila, a larger cirrus sac, a greater number of segments, and more numerous testes. The morphology of S. oryctolagi n. sp. is most similar to that of S. sinensis. It is distinguished from the latter species by its relatively small strobila, larger number of segments, smaller size of eggs, and much larger cirrus sac, which is substantially extending in a medial direction. In addition, a genital papilla is present in S. sinensis , but absent in S. oryctolagi. These findings indicate that species of Schizorchis are widespread in leporid mammals, contrary to the widespread opinion that the latter genus is specific to ochotonid lagomorph mammals. They are congruent, however, with the hypothesis of a close phylogenetic relationship between species of Schizorchis and Mosgovoyia. The occurrence of Schizorchis spp. in leporids is considered relict, vestigial from wider geographical and host ranges of this parasite genus during the Pleistocene.

  9. Small mammals of the Mongolian mountain steppe region near Erdensant: insights from live-trapping and bird pellet remains.

    Directory of Open Access Journals (Sweden)

    Joanne L. Isaac

    2005-12-01

    Full Text Available Relatively little is known of the distribution, abundance and ecology of small mammals in Mongolia and as a result there is scant knowledge of the effects of environmental and anthropogenic factors on small mammal populations. The aim of this study was to assess the occurrence of small mammals in mountain steppe habitat from live-trapping and analysis of mammal remains from raptor pellets and below nests. During live-trapping, root voles ( Microtus oeconemus were the most commonly caught species accounting for 47.5 % of captures, striped hamsters ( Cricetulus barabensis and pika ( Ochotona hyperborea accounted for 30 % and 22.5 % of captures respectively. Temperature influenced trapping success, with small mammals appearing to avoid being active at temperatures over 20 ̊C. The three species caught on the trapping grid appeared to avoid competition for resources through both temporal and spatial differences in the use of available habitat. Mammals identified from raptor pellets and other remains included the grey hamster ( Cricatulus migratorius , Siberian marmot ( Marmota sibirica , red fox ( Vulpes vulpes , long-tailed souslik ( Citellus undulatus and the Daurian mole ( Myospalax aspalax. Results are discussed in terms of their relevance to the conservation of mammals in Mongolia and their co-existence with livestock and humans.

  10. Evolution of CCL11: genetic characterization in lagomorphs and evidence of positive and purifying selection in mammals.

    Science.gov (United States)

    Neves, Fabiana; Abrantes, Joana; Esteves, Pedro J

    2016-07-01

    The interactions between chemokines and their receptors are crucial for differentiation and activation of inflammatory cells. CC chemokine ligand 11 (CCL11) binds to CCR3 and to CCR5 that in leporids underwent gene conversion with CCR2. Here, we genetically characterized CCL11 in lagomorphs (leporids and pikas). All lagomorphs have a potentially functional CCL11, and the Pygmy rabbit has a mutation in the stop codon that leads to a longer protein. Other mammals also have mutations at the stop codon that result in proteins with different lengths. By employing maximum likelihood methods, we observed that, in mammals, CCL11 exhibits both signatures of purifying and positive selection. Signatures of purifying selection were detected in sites important for receptor binding and activation. Of the three sites detected as under positive selection, two were located close to the stop codon. Our results suggest that CCL11 is functional in all lagomorphs, and that the signatures of purifying and positive selection in mammalian CCL11 probably reflect the protein's biological roles. © The Author(s) 2016.

  11. Advances in Research on Hypoxia Adaptation Mechanisms of Native Plateau Animals%高原土生动物低氧适应机制研究进展

    Institute of Scientific and Technical Information of China (English)

    申健(综述); 牛廷献(审校); 史智勇

    2015-01-01

    Plateau hypoxia adaptation is the core of the plateau medical research , the mechanism of which is mainly a series of complex compensatory established around the hypoxia .Native plateau animals are ideal models of plateau hypoxia adaptation research.Based on the Tibetan pig,plateau pika,the Tibetan ante-lope and Juema minipig,researchers conducted basic research on their characteristics of hematology,pulmo-nary vascular structure and function,hypoxia adaptation related genes,etc.,but there is not enough research on the cellular and molecular level.Research on native plateau animals of hypoxia adaptation mechanisms can provide theoretical basis for the study and development of the plateau experimental animals .%高原低氧适应是高原医学研究的核心,高原低氧适应的机制主要是围绕缺氧而建立起的一系列复杂的代偿。高原土生动物是研究高原低氧适应的理想模型,以藏猪、高原鼠兔、藏羚羊和蕨麻小型猪为例,研究者们多以其血液学特征、肺血管结构和功能及低氧适应相关基因等方面作为基础研究,但目前在细胞及分子水平研究不够深入,研究土生动物低氧适应机制,可以为高原实验动物的开发研究提供理论基础。

  12. Landscape composition and spatial prediction of alveolar echinococcosis in southern Ningxia, China.

    Directory of Open Access Journals (Sweden)

    David R J Pleydell

    Full Text Available Alveolar echinococcosis (AE presents a serious public health challenge within China. Mass screening ultrasound surveys can detect pre-symptomatic AE, but targeting areas identified from hospital records is inefficient regarding AE. Prediction of undetected or emerging hotspots would increase detection rates. Voles and lemmings of the subfamily Arvicolinae are important intermediate hosts in sylvatic transmission systems. Their populations reach high densities in productive grasslands where food and cover are abundant. Habitat availability is thought to affect arvicoline population dynamic patterns and definitive host-intermediate host interactions. Arvicoline habitat correlates with AE prevalence in Western Europe and southern Gansu Province, China.Xiji County, Ningxia Hui Autonomous Region, borders southern Gansu. The aims of this study were to map AE prevalence across Xiji and test arvicoline habitat as a predictor. Land cover was mapped using remotely sensed (Landsat imagery. Infection status of 3,205 individuals screened in 2002-2003 was related, using generalised additive mixed models, to covariates: gender; farming; ethnicity; dog ownership; water source; and areal cover of mountain pasture and lowland pasture. A Markov random field modelled additional spatial variation and uncertainty. Mountain pasture and lowland pasture were associated with below and above average AE prevalence, respectively.Low values of the normalised difference vegetation index indicated sub-optimality of lowland pasture for grassland arvicolines. Unlike other known endemic areas, grassland arvicolines probably did not provide the principal reservoir for Echinococcus multilocularis in Xiji. This result is consistent with recent small mammal surveys reporting low arvicoline densities and high densities of hamsters, pikas and jerboas, all suitable intermediate hosts for E. multilocularis, in reforested lowland pasture. The risk of re-emergence is discussed. We

  13. Evolutionary history of lagomorphs in response to global environmental change.

    Directory of Open Access Journals (Sweden)

    Deyan Ge

    Full Text Available Although species within Lagomorpha are derived from a common ancestor, the distribution range and body size of its two extant groups, ochotonids and leporids, are quite differentiated. It is unclear what has driven their disparate evolutionary history. In this study, we compile and update all fossil records of Lagomorpha for the first time, to trace the evolutionary processes and infer their evolutionary history using mitochondrial genes, body length and distribution of extant species. We also compare the forage selection of extant species, which offers an insight into their future prospects. The earliest lagomorphs originated in Asia and later diversified in different continents. Within ochotonids, more than 20 genera occupied the period from the early Miocene to middle Miocene, whereas most of them became extinct during the transition from the Miocene to Pliocene. The peak diversity of the leporids occurred during the Miocene to Pliocene transition, while their diversity dramatically decreased in the late Quaternary. Mantel tests identified a positive correlation between body length and phylogenetic distance of lagomorphs. The body length of extant ochotonids shows a normal distribution, while the body length of extant leporids displays a non-normal pattern. We also find that the forage selection of extant pikas features a strong preference for C(3 plants, while for the diet of leporids, more than 16% of plant species are identified as C(4 (31% species are from Poaceae. The ability of several leporid species to consume C(4 plants is likely to result in their size increase and range expansion, most notably in Lepus. Expansion of C(4 plants in the late Miocene, the so-called 'nature's green revolution', induced by global environmental change, is suggested to be one of the major 'ecological opportunities', which probably drove large-scale extinction and range contraction of ochotonids, but inversely promoted diversification and range expansion of

  14. Molecular characterization of adipose tissue in the African elephant (Loxodonta africana).

    Science.gov (United States)

    Nilsson, Emeli M; Fainberg, Hernan P; Choong, Siew S; Giles, Thomas C; Sells, James; May, Sean; Stansfield, Fiona J; Allen, William R; Emes, Richard D; Mostyn, Alison; Mongan, Nigel P; Yon, Lisa

    2014-01-01

    Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body

  15. Molecular Characterization of Adipose Tissue in the African Elephant (Loxodonta africana)

    Science.gov (United States)

    Choong, Siew S.; Giles, Thomas C.; Sells, James; May, Sean; Stansfield, Fiona J.; Allen, William R.; Emes, Richard D.; Mostyn, Alison; Mongan, Nigel P.; Yon, Lisa

    2014-01-01

    Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body

  16. Productivity and costs of slash bundling in Nordic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kaerhae, K.; Vartiamaeki, T. [Metsaeteho Oy, P.O. Box 101, FI-00171 Helsinki (Finland)

    2006-12-15

    The number of slash bundlers and the volume of slash bundling have been rapidly increasing during the last few years in Finland. However, no comprehensive time or follow-up studies have been carried out on slash bundling technology in Finland or in any other country. Metsateho Oy carried out studies on the productivity and costs of slash bundling in different Nordic recovering conditions. The study methods included both time and follow-up studies. Data were collected during the summer and winter period primarily in Norway spruce (Picea abies L. Karst.) dominated clear cutting sites. The bundling techniques performed by different types of bundler (Fiberpac 370, Timberjack 1490D, Pika RS 2000, Valmet WoodPac) were studied. The average productivity of slash bundling was 18.1 bundles per operating (E{sub 15}, including delays shorter than 15min) hour with the Timberjack 1490D and Fiberpac 370 bundlers in the follow-up study. The operator of the slash bundler had the greatest effect on the productivity of bundling. The prerequisite for increased bundling volumes is a reduction in the costs of the most expensive sub-stage of the bundling supply chain, i.e. bundling itself. This requires improved recovery conditions at bundling sites, increased bundling productivity, larger sized bundles, and the execution of bundling operations in two work shifts using an efficient bundler and effective operator working methods. Implementation of these development measures will bring the bundling supply chain up to a speed that makes it the most competitive supply chain for forest chips in terms of total supply costs for long-distance transportation distances of more than 60km. (author)

  17. Molecular characterization of adipose tissue in the African elephant (Loxodonta africana.

    Directory of Open Access Journals (Sweden)

    Emeli M Nilsson

    Full Text Available Adipose tissue (AT is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit, Lepus oiostolus (woolly hare, and members of the Ochotonidae (Pika. Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition

  18. Faster speciation and reduced extinction in the tropics contribute to the Mammalian latitudinal diversity gradient.

    Directory of Open Access Journals (Sweden)

    Jonathan Rolland

    2014-01-01

    Full Text Available The increase in species richness from the poles to the tropics, referred to as the latitudinal diversity gradient, is one of the most ubiquitous biodiversity patterns in the natural world. Although understanding how rates of speciation and extinction vary with latitude is central to explaining this pattern, such analyses have been impeded by the difficulty of estimating diversification rates associated with specific geographic locations. Here, we use a powerful phylogenetic approach and a nearly complete phylogeny of mammals to estimate speciation, extinction, and dispersal rates associated with the tropical and temperate biomes. Overall, speciation rates are higher, and extinction rates lower, in the tropics than in temperate regions. The diversity of the eight most species-rich mammalian orders (covering 92% of all mammals peaks in the tropics, except that of the Lagomorpha (hares, rabbits, and pikas reaching a maxima in northern-temperate regions. Latitudinal patterns in diversification rates are strikingly consistent with these diversity patterns, with peaks in species richness associated with low extinction rates (Primates and Lagomorpha, high speciation rates (Diprotodontia, Artiodactyla, and Soricomorpha, or both (Chiroptera and Rodentia. Rates of range expansion were typically higher from the tropics to the temperate regions than in the other direction, supporting the "out of the tropics" hypothesis whereby species originate in the tropics and disperse into higher latitudes. Overall, these results suggest that differences in diversification rates have played a major role in shaping the modern latitudinal diversity gradient in mammals, and illustrate the usefulness of recently developed phylogenetic approaches for understanding this famous yet mysterious pattern.

  19. Plant traits and soil properties in pasture mini-patches in an alpine meadow%高寒草甸草地微斑块植物特征及其土壤性质的研究

    Institute of Scientific and Technical Information of China (English)

    石明明; 张永超; 张典业; 任运涛; 宗文杰; 傅华; 牛得草

    2015-01-01

    meadows with a light,moderate,and heavy density of plateau pika (Ochotona curzoniae )burrows.The plant community structure and soil properties were evaluated for five types of patches in meadows with a moderate number of burrows.Some mini-patches were characterized by a high a-bundance of a single species,with mini-patch areas ranging from 0.5 m2 to 100 m2 in an alpine meadow (not in-cluding background patches).These types of patches were named according to the main plant species.We chose three approximately 1-hectare sample sites with different burrow densities;light,moderate,and heavy. Three quadrats (20 m×20 m)were placed randomly to determine the types,number,and area of patches with-in each site.We chose five types of patches from the three sample sites,and selected three typical patches for each type to determine the plant community structure and soil properties.Quadrat sampling (1 m×1 m)was used to determine basic plant traits (composition,height,cover degree,above-ground biomass of vegetation) and soil properties (organic carbon,pH,total nitrogen,available nitrogen,total phosphorus,available phos-phorus)in the patches.The meadows with moderate burrow density had the most types of patches and the greatest abundance of patches.The total area of patches tended to increase with greater deterioration caused by plateau pika.The number and areas of Potentilla anserine ,Ligularia virgaurea ,and Anemone rivularis pat-ches tended to increase,and their areas increased dramatically from the moderate to heavy burrow density.The number and areas of Anaphalis lacteal and Leontopodium japonicum patches tended to decrease,and these patches tend to disappear from as the burrow density increased from moderate to heavy.There were few main types of pasture mini-patches,and the pattern of patches was relatively simple under heavy burrow density.An abnormal increase in the biomass of a single species was the main characteristic of the patches.The expanding propagation of single

  20. Biodiversity and biogeography of hydrothermal vent species in the western Pacific: a biological perspective of TAIGA project

    Science.gov (United States)

    Seo, M.; Watanabe, H.; Nakamura, M.; Sasaki, T.; Ogura, T.; Yahagi, T.; Takahashi, Y.; Ishibashi, J.; Kojima, S.

    2012-12-01

    Deep-sea hydrothermal vents are scientifically interesting environments where strong interactions of geology, chemistry, and biology can be observed. The hydrothermal vents are geologically controlled in association with magmatic activities while diversity of chemicals (such as hydrogen sulfide) contained in hydrothermal fluid is controlled by geochemical interaction between heated seawater and surrounding rocks. In addition to those geological and chemical characters of hydrothermal vents, high biomasses of chemosynthetic community have been known around many vents since the first discovery in the 1970s. To understand the unique system and diversity of biological communities associated with vents is highly valuable in geological, chemical, and biological sciences. As an activity of the research project "TAIGA (Trans-crustal Advection & In-situ bio-geochemical processes of Global sub-seafloor Aquifer)" (Representative: Tetsuro Urabe, Department of Earth & Planetary Science, the University of Tokyo), we analyzed population structures and connectivity as well as larval ecology of various hydrothermal vent species in the Okinawa Trough and the Mariana Trough in an attempt to estimate faunal transitional history associated with hydrothermal activities. The specimens analyzed in the present study were collected by R/V Yokosuka with manned submersible Shinkai6500 and R/V Natsushima with ROV Hyper-Dolphin during YK10-11 and NT11-20 cruises, respectively. In the Mariana Trough (YK10-11), benthic and planktonic faunas were investigated by multiple sampling and use of plankton samplers in three hydrothermal vents (Snail, Archaean, and Urashima-Pika fields). Faunal compositions were then compared as well as size compositions and genetic diversities of major vent species among local populations. In the Okinawa Trough (NT11-20), multiple quantitative sampling was made with simultaneous environmental measurements at more than two sites in five hydrothermal vents (Minami

  1. Pasture degradation modifies soil organic matter properties and biochemical functioning in Tibetan grasslands

    Science.gov (United States)

    Spielvogel, Sandra; Steingräber, Laura; Schleuß, Per; Kuzyakov, Yakov; Guggenberger, Georg

    2015-04-01

    Kobresia pastures of the Tibetan Plateau represent the world's largest alpine ecosystem. Moderate husbandry on Kobresia pastures is beneficial for the storage of soil organic carbon (OC), nitrogen (N) and other nutrients and prevents erosion by establishment of sedge-turf root mats with high OC allocation rates below ground. However, undisturbed root mats are affected by freezing and thawing processes, which cause initial ice cracks. As a consequence decomposition of root mat layers will be accelerated and current sedentarization programs with concomitant increased grazing intensity may additionally enhance root mat degradation. Finally, cracks are enlarged by water and wind erosion as well as pika activities until bare soil surface areas without root mat horizons occur. The aim of this study was to understand the impact of the root mat layer on soil organic carbon stabilization and microbial functioning depending on soil depths and to predict future changes (OC, N and nutrient losses, soil microbial functioning in SOM transformation) by overgrazing and climate change. We investigated the mineral soil below Kobresia root mats along a false time degradation sequence ranging from stage 1 (intact root mat) to stage 4 (mats with large cracks and bare soil patches). Vertical gradients of δ13C values, neutral sugar, cutin and suberin contents as well as microbial biomass estimated by total phospholipid fatty acid (PLFA), microbial community composition (PLFA profiles) and activities of six extracellular enzymes involved in the C, N, and P cycle were assessed. Soil OC and N contents as well as C/N ratios indicate an increasing illuviation of topsoil material into the subsoil with advancing root mat degradation. This was confirmed by more negative δ13C values as well as significantly (p ≤ 0.05) increasing contributions of cutin derived hydroxy fatty acids to OC in the subsoils from degradation stages 1 to 4. PLFA profiles were surprisingly similar in the subsoils of

  2. Behavior of trace metals in the hydrothermal plume at two sites on the Izu-Bonin-Mariana Arc

    Science.gov (United States)

    Shitashima, K.

    2004-12-01

    Deep-sea hydrothermal systems play an important role in the oceanic geochemical cycles of trace metals. High concentration of trace metals of the basalt origin is discharged into the deep sea via the hydrothermal plume. The hydrothermal plume is widely diffused to the ocean by mixing with ambient seawater. The processes of input and removal in the diffusing hydrothermal plume differ by individual hydrothermal systems. In this presentation, the behavior of trace metals in the hydrothermal plume of two sites on the Izu-Bonin-Mariana Arc is compared. This study was funded by the O`Archaean ParkO_L project of MEXT. The hydrothermal plume samples were taken from the Suiyo Seamount and the southern Mariana Trough (Pika Site). The mini CTDT-RMS mounted twelve 1.2L Niskin bottles was installed onto the manned submersible. And the hydrothermal plume samples were collected with monitoring the anomaly of temperature and turbidity. The samples were immediately filtered in an onboard clean bench. Unfiltered sample for analysis of total (particulate + dissolved) trace metal and filtered sample for analysis of dissolved trace metal were acidified. Trace metals (Al, Mn, Fe, Cu and Zn) in the hydrothermal plume samples were analyzed by GFAAS. The ranges of concentration of Al, Mn, Fe, Cu and Zn in the hydrothermal plume samples collected from two sites are _`15uM, _`5uM, _`5uM, _` 0.2uM and _`0.6uM, respectively. The particulate phase is predominant form in Al, Fe, Cu and Zn, and Mn shows the superiority of dissolved form. At the Suiyo Seamount, the hydrothermal active site is located in the bottom of caldera. On the other hand, the hydrothermal active site exists on the top of off-ridge seamount at the southern Mariana Trough. The diffusion process of trace metals in the hydrothermal plume to the ocean differed by the topographic factor in two sites. It suggests that trace metals discharged from the vents are hardly diffused to the ocean surmounting the Suiyo Seamount caldera

  3. Vulnerability on the Roof of the World: Resilience to Climate Change and Natural Resource Policies on the Tibetan Plateau

    Science.gov (United States)

    Klein, J. A.; Hopping, K. A.; Yeh, E.; Hu, J.; Nyima, Y.; Boone, R.; Galvin, K.; Kang, S.; Ojima, D. S.

    2010-12-01

    Pastoralists on the Tibetan Plateau are a marginalized people living in an extreme environment and may be especially vulnerable as the system approaches critical thresholds. In Tibet, temperatures are increasing several times more than the global average while the frequency and severity of severe snowstorms is predicted to increase. Pastoralists are also experiencing reduced mobility and severe grazing restrictions. We are using interdisciplinary frameworks and methods that include a multifactor ecological experiment, household interviews, remote sensing, and a coupled ecosystem and household decision-making model to examine herder and ecosystem vulnerability to climate change and extreme weather events within the context of changing natural resource policies in China. The fully factorial ecological experiment includes two climate changes (warming and spring snow additions) and two types of grazing (yak and pika). We established the experiment in 2008 within the Tibet Autonomous Region (4,870 m) and are monitoring microclimate, vegetation, nutrient availability, carbon fluxes and stable isotopes. We are investigating the sensitivity of the system, whether it is likely to cross critical thresholds, and how resilient this system may be to predicted climate and land use changes. Semi-structured interviews on indigenous knowledge and vulnerability complement the ecological experimental work. We are asking herders about climatic and ecological change and vulnerability to snow disasters. To integrate our ecological and social findings, we are coupling an ecosystem model to an agent-based pastoral household model. Our results from the experiment and the indigenous knowledge study suggest that Kobresia pygmaea, the dominant species and primary grazing resource, is vulnerable to warming. Snow additions can partially mediate this effect. Herders throughout this region share common knowledge about both climatic and ecological changes, but appear to be more closely attuned to

  4. Environmental change and cultural adaptation in the southern Caucasus: latest results from Aghitu-3 Cave, Armenia

    Science.gov (United States)

    Kandel, Andrew; Gasparyan, Boris; Bruch, Angela; Nahapetyan, Samvel; Weissbrod, Lior

    2014-05-01

    consisting of fine silt horizons with alternating layers of frost shattered basalt slabs. Pollen shows a change to boreal forest, and the increased presence of pika among the micromammals suggests colder and more barren conditions than today. The wide spectrum of micromammals further points to their likely accumulation by a non-selective raptor such as eagle owl. Fish remains of brown trout confirm the presence of a significant fluvial corridor, likely the nearby Vorotan River. This agrees with the charcoal remains identified thus far, which have the signature of a riparian woodland. The sedimentary sequence ends here, truncated at about 24,000 cal BP by late Holocene deposits of anthropogenic origin.

  5. Characterization of Dissolved Organic Matter from Deep-sea Floor Hydrothermal Vents in South Mariana Backarc Spreading Center

    Science.gov (United States)

    Kitajima, F.; Yamanaka, T.

    2004-12-01

    In South Mariana Backarc Spreading Center, a few active hydrothermal fields are located. We investigated a characterization of dissolved organic matter (DOM) from hydrothermal vents in this area, in order to clarify the biosphere beneath deep-sea floor. Hot water sample was collected from a drilled hole (APM01 located in Fryer site, 12o 55.22fN, 143o 37.16fE, depth 2850m) during the ROPOS/TN167A cruise in March 2004. The hole had been drilled during Hakurei-Maru 2 cruise in January 2004. Another hot water sample was collected from a natural black smoker located in Pika site (12o 55.15fN, 143o 36.96fE, depth 2773m) during YK03-09 cruise. In this investigation, we developed a standalone filtration system in order to collect and enrich dissolved organic matter of quite low concentration. This system was designed to be put near hydrothermal vents for at least 24h. This system has an ODS disk (EmporeTM High Performance Extraction Disk C18 90mmφ) with a pre-filter (Whatman GMF 1 μ)m filter paper) to adsorb dilute organics. We collected DOM from the APM01 casing pipe for about 30h (Tmax = 25-30 o C, the estimated volume of filtrated water is max. 300L) using this filtration system. Adsorbed organics were eluted with methanol for 12h twice and toluene once using soxhlet extractor. Recovered amounts of methanol eluents are 72.8mg for APM01, and 89.7mg for the black smoker. Prior to GCMS analysis, we carried out high resolution 1 H-NMR measurement (400MHz), together with the DOM samples collected from the Suiyo Seamount in July-August 2001 and August 2002. Most of the samples show signals in the region of 3-4 ppm, and the samples from the vents of relatively low temperatures (APM01 and AP04: the natural vent at the Suiyo Seamount, temperature 8-48o C ) show signals also in the region of 0.8-1.6 ppm.

  6. Using a Multi-Method Approach to Examine Social-Ecological Vulnerability to Climate Change and Natural Resource Policies on the Tibetan Plateau

    Science.gov (United States)

    Klein, J.; Hopping, K. A.; Yeh, E.; Nyima, Y.; Galvin, K.; Boone, R.; Dorje, T.; Ojima, D. S.

    2012-12-01

    Pastoralists and ecosystems on the Tibetan Plateau are facing a suite of novel stresses. Temperatures are increasing several times more than the global average. The frequency and severity of severe snowstorms, which lead to critical losses of livestock, are also increasing. Pastoralists are also experiencing changes to their livelihood activities, including reduced mobility and severe grazing restrictions. We are using interdisciplinary frameworks and methods that integrate results from a multifactor ecological experiment, household interviews, remote sensing, and a coupled ecosystem and household decision-making model to examine herder and ecosystem vulnerability to climate change and extreme weather events (snow disasters) within the context of changing natural resource management policies in China. The fully factorial ecological experiment includes two climate changes (warming and spring snow additions) and two types of grazing (yak and pika) that are being affected by current policy. We established the experiment in 2008 within the Tibet Autonomous Region. We are monitoring microclimate, vegetation, nutrient availability, ecosystem carbon fluxes and stable isotope signatures of select plant species. Through this experiment, we are investigating the sensitivity of the system, whether it can cross critical thresholds, and how resilient this system may be to predicted future climate and land use changes. Semi-structured, in-depth interviews on indigenous knowledge and vulnerability complement the ecological experimental work. We are asking herders about climate and ecological change and their drivers and are also conducting interviews on vulnerability to snow disasters across a three site, 300-500mm precipitation gradient. We are using remote sensing to identify biophysical landscape change over time. To integrate our ecological and social findings, we are coupling the Savanna ecosystem model to the DECUMA agent-based pastoral household model. Our results to date

  7. 四川夹金山小型兽类区系及多样性%Fauna and species diversity of small mammals in Jiajin Mountains, Sichuan Province, China

    Institute of Scientific and Technical Information of China (English)

    涂飞云; 唐明坤; 刘洋; 孙治宇; 张修月; 岳碧松; 刘少英

    2012-01-01

    The Jiajin Mountains,locating in the mountainous southwest of China,has been a hotbed of biodiversity research for the past several decades.We conducted a species diversity survey of small mammals at different elevation bands and in various habitat types.A total of 927 individuals were captured.These animals belonged to 4 orders,8 families,and 35 species including 16 rodents,16 insectivores,and 3 pikas.Analysis of these data indicated that:1) species number on south slopes (31) was higher than that on the north slopes (20) because of north-south climate differences; 2) among the 35 species,15 species were endemic to China,and high diversity of insectivore species was obtained in this unique region;3) Palearctic composition on north slopes is significantly higher than on the opposite slopes which might be due to northsouth migration restrictions of Oriental and Palearctic species from Jiajin Mountains ; 4) the highest species diversity was in the mid-altitudes (2 400-3 000 m) in the southern part because of serious human disturbance in low altitude regions and simple vegetation types in high altitude regions,while the elevations exhibiting the highest species diversity on north slopes was higher (3 000-3 600 m),which might be due to dry climate at low altitude regions on north slopes; The complex topographic configurations in the Jiajin Mountains contributed to species divergence and provided diversified habitats for small mammals,thus high species diversity and abundant endemic species were observed in this region.High diversity of insectivore species might be related to more evolutionary advantages in the unique area.%夹金山位于西南山地,是近年来生物多样性研究的热点地区,我们对其不同海拔和不同生境类型的小型兽类进行了调查,共捕获927号个体,隶属4目8科35种,其中啮齿类16种,食虫类16种,鼠兔类有3种.数据分析显示:(1)因南北气候差异,夹金山南坡物种(31)显著高于北坡(20);(2)在35

  8. A review of the current status of Echinococcus and hydatid disease,with notes on some informative achievements in China%我国棘球绦虫及棘球蚴病研究进展

    Institute of Scientific and Technical Information of China (English)

    林宇光; 卢明科; 洪凌仙

    2012-01-01

    There are seven Echinococcus pathogens of hydatid disease reported from the world, and five species are found in China. Among them, E. shiquicus, collected from eastern Tibetan plateau in Sichuan Province of China, is described as a new species by Xiao et al (2005). Its adult worm is the smallest one in Echinococcus spp. The majority of them contain a single immature proglottid and a single gravid proglottid, lacking mature proglottid. The Tibetan fox, Vulpes ferrilata , is confirmed as the final host of E. shiquicus, and the plateau pika, Ochotona curzoniae, serves as the intermediate host. In the host liver, the metacestode develops into unilocular hydatid cyst, with no daughter cyst. Domestic dog and human are not found to be infected with either adult or metacestode so far. E. granulosus is recognized with two forms on the basis of differences in host-specify. The Northern Form of E. granulosus distributes in the holarctic zone of tundra and boreal forest or Taiga. Its natural cycle is perpetuated by the predator-prey relationship existing between wolf and large deer. The Domestic Form (European Form) of E. granulosus reveals nearly cosmopolitan distribution, and its life cycle involves both domestic dog and ungulates as final and intermediate host respectively. The latter form appears to be the most important pathogen of hydatid disease in the world. In China, the unilocular dydatid disease pathogen belongs to the Domestic Form, but there probably exist complex infection with the Northern Form in some pasture lands at Northwest China. E. multilocularis or multilocular (alveolar) hydatid cyst is recognized as an important pathogen of zoonoses in the world. This cestode-pathogen distributes throughout the holarctic zone of tundra, involving Europe, Siberia, Northern Japan, subarctic islands and North America. The typical life cycle involves foxes and rodents. According to the published data from local hospitals or institutes of parasitic disease in China, during