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Sample records for plateau environment characterized

  1. A plateau-valley separation method for multifunctional surfaces characterization

    DEFF Research Database (Denmark)

    Godi, Alessandro; Kühle, A.; De Chiffre, Leonardo

    2012-01-01

    Turned multifunctional surfaces are a new typology of textured surfaces presenting a flat plateau region and deterministically distributed lubricant reservoirs. Existing standards are not suitable for the characterization of such surfaces, providing at times values without physical meaning. A new...

  2. Sino-Japanese Teamwork Probes Environment Changes on Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ With the support of a CAS project on Holocene environmental changes and their influences on the ecosystem of the Tibetan Plateau, a research group headed by Prof. Zhu Liping from the CAS Institute of Tibetan Plateau Research and their Japanese collaborators carried out a field survey in Puma Yumco area on the Tibetan Plateau from September 8 to 20.

  3. 12 kaBP lake environment on the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    李炳元; 王苏民; 朱立平; 李元芳

    2001-01-01

    The systemic analyses have been carried out in this paper to the paleolake shorelines, paleolake sediments and paleoclimatic proxies of 20 lakes, in which there were 12 kaBP dating data on the Tibetan Plateau. The results showed that the paleolake level had apparently risen during 14-11 kaBP, the glaciers melting period, in the Tibetan area and Northwest China. Especially, much more increasing amplitude supplied by thawy glaciers water occurred than in the best period of Holocene. The temperate-humid climate around 12 kaBP appeared in the Tibetan area and even in the whole China. This event may be compared with the Bolling/Allerod warm period which was reflected by Europe and Greenland ice core records. It showed that the B/A event was not a regional one in the North Atlantic area.

  4. Prehistoric Human Adaptation to Tibetan Plateau Environment indicated by 151 site in the Qinghai Lake Basin

    Science.gov (United States)

    Zhang, Dongju; Dong, Guanghui; Wang, Qianqian; Ren, Xiaoyan; Chen, Fahu

    2017-04-01

    Current study indicates that Northeastern Tibetan Plateau (NETP) is one of the first widely occupied places by prehistory people on the Tibetan Plateau, which makes NETP very important to understand the human history on the plateau and human adaptation to high elevation environment. Hence, 151 site, a paleo- to Epi-Paleolithic site in the Qinghai Lake basin on NETP, is chosen to excavate. Thousands pieces of animal bones, hundreds pieces of stone artifacts and several possible hearths were unearthed and obtained during two excavation seasons. Carefully redating of the site shows that it was first occupied shortly around 15 ka BP, then reoccupied from 9000-6000 a BP more intensely. Preliminary study of the site suggest that the first appearance of human in Qinghai Lake basin is closely related to the amelioration of the Last Deglaciation and the prevalence of microlithic technology in North China, which may enlighten the study of early human migration on to whole plateau; however, the latter more intense human occupation in 151 site is not only closely related to the warm and stable early-mid Holocene climate but also provoked by early millet agriculture in neighbor low-elevation Loess plateau.

  5. Prehistoric Human Dispersal to the Tibetan Plateau and Adaptation to the High Altitude Environment

    Science.gov (United States)

    Zhang, Dongju; Dong, Guanghui; Chen, Fahu

    2016-04-01

    Human history of the Tibetan Plateau and human adaptation to the high altitude environment is hotly debated in the past decade among archaeological, anthropological, genetic, and even past climate change studies. Based on previous studies on the Tibetan Plateau and our own archaeological studies in northeastern Tibetan Plateau (NETP), we propose that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in NETP. This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) when human adapted to the high altitude environment and climate change with different strategies and techniques. Particularly, the prevail of microlithic technology in North China provoked hunter-gatherers' first visit to the NETP in relatively ameliorated last Deglacial period, and the quick development of millet farming and subsequent mixed barley-wheat farming and sheep herding facilitated farmers and herders permanently settled in NETP, even above 3000 masl, during mid- and late Holocene.

  6. Characterizing environment friendly tourists

    OpenAIRE

    Reinsberg, Cicilie; Vinje, Linn Therese

    2010-01-01

    The central aim of sustainable tourism research today is to find tourists that have a low environmental impact on destinations, which can also be defined as environment friendly tourists. The majority of earlier studies on this topic have focused on characteristics of ecotourists, assuming that these are the only tourists that are environment friendly. Few have tried to identify characteristics of environment friendly tourists using a sample from the general tourist population....

  7. The property, age and formation environment of the palaeokarst in Qinghai-Xizang Plateau

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The karst landforms distributed on the Qinghai-Xizang (Tibet) Plateau can be genetically classed with the Tertiary underground karst, which were gradually exhumed to the surface with the uplift of the plateau during Quaternary period. The relative deposits of the Tertiary palaeokarst processes, such as the residuum and speleothem, were discovered recently in the southern and southeastern fringe areas of the plateau, where has geological-currently been disintegrated by the headward erosion processes of the modern river systems. The major chemical components of the clay portion of the residuum consist mainly of SiO2, Al2O3 and Fe2O3. The clay minerals composition of the clay portion belongs to illite-kaolinite pattern for most of the residuum samples, and kaoliniteillite pattern for a few of the samples. It can be judged from the silicic acid index and the clay minerals composition that the formation of the residuum of the Plateau was in its initial phase.However, such a lower chemical weathering index only reflected the weathering degree in the bottom or lower parts of the lateritic weathering crust. The relatively intensive chemical weathering processes of the surface layers of the lateritic weathering crust could be logically speculated. The surface feature textures of quartz grains in the residuum were formed mainly by the chemical erosion, which revealed a long-term humid-tropical environment when the residuum and the palaeokarst formed.

  8. Seismic source characterization for the Shillong Plateau in Northeast India

    Science.gov (United States)

    Baro, Olympa; Kumar, Abhishek

    2017-09-01

    The present study aims at understanding the seismotectonic province of the Shillong Plateau (SP) by identifying the potential seismic source zones within a radius of 500 km from the centre of the SP. From existing literature and earthquake (EQ) data, the seismotectonic region is found to vary in terms of seismicity, tectonic features, geology, thickness of overburden, rupture characteristics and rate of movement. Thus, entire 500-km-radius seismotectonic region is divided into four seismic source zones: namely (1) the Shillong Plateau-Assam Valley Zone (SP-AVZ), (2) the Indo-Burma Ranges Zone (IBRZ), (3) the Bengal Basin Zone (BBZ) and (4) the Eastern Himalaya Zone (EHZ). EQ catalogues for each source zone is analysed for completeness of magnitude and time. Seismic parameter b estimated using a maximum likelihood method is found to be 0.91 ± 0.03, 0.94 ± 0.02, 0.80 ± 0.03 and 0.89 ± 0.03 for the SP-AVZ, IBRZ, BBZ and EHZ, respectively. In addition, the maximum likelihood method is used to estimate the mean annual activity rate, maximum possible magnitude ( m max), return period and probability of exceedance for the four zones. The b values estimated suggest that the BBZ is seismically more active; however, the rate of occurrence of EQs is highest in the IBRZ. Findings from this study are an indication of the relative contribution from each of the four seismic source zones towards a seismic hazard of the SP.

  9. Demonstration Research into Eco-environment Rehabilitation on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    Xu Mingxiang; Liu Guobin

    2002-01-01

    @@ As part of the "Action Plan for the Development of Western China," the project is conducted by the Institute of Soil & Water Conservation under CAS and the Ministry of Water Resources. It focuses on the rehabilitation of the regional eco-environment, such as a large-scale afforestation drive on enclosed hillsides, efforts to turn the reclaimed farmland on steep mountain slopes into woodland and pastureland, the greening of mountainous areas and speeding up the restoration tempo of the original vegetation on the Loess Plateau. An experiment & demonstration zone has been co-established by the CAS Institute and the provincial Government of Shaanxi. Located in a hillygully region sprawling in the heartland of the Plateau,the zone includes nine townships, covering 707 square kilometers in total area. Since its start in 2000, the project has scored remarkable progress:

  10. Comparative Proteomics Analyses of Kobresia pygmaea Adaptation to Environment along an Elevational Gradient on the Central Tibetan Plateau

    Science.gov (United States)

    Li, Xiong; Yang, Yunqiang; Ma, Lan; Sun, Xudong; Yang, Shihai; Kong, Xiangxiang; Hu, Xiangyang; Yang, Yongping

    2014-01-01

    Variations in elevation limit the growth and distribution of alpine plants because multiple environmental stresses impact plant growth, including sharp temperature shifts, strong ultraviolet radiation exposure, low oxygen content, etc. Alpine plants have developed special strategies to help survive the harsh environments of high mountains, but the internal mechanisms remain undefined. Kobresia pygmaea, the dominant species of alpine meadows, is widely distributed in the Southeastern Tibet Plateau, Tibet Autonomous Region, China. In this study, we mainly used comparative proteomics analyses to investigate the dynamic protein patterns for K. pygmaea located at four different elevations (4600, 4800, 4950 and 5100 m). A total of 58 differentially expressed proteins were successfully detected and functionally characterized. The proteins were divided into various functional categories, including material and energy metabolism, protein synthesis and degradation, redox process, defense response, photosynthesis, and protein kinase. Our study confirmed that increasing levels of antioxidant and heat shock proteins and the accumulation of primary metabolites, such as proline and abscisic acid, conferred K. pygmaea with tolerance to the alpine environment. In addition, the various methods K. pygmaea used to regulate material and energy metabolism played important roles in the development of tolerance to environmental stress. Our results also showed that the way in which K. pygmaea mediated stomatal characteristics and photosynthetic pigments constitutes an enhanced adaptation to alpine environmental stress. According to these findings, we concluded that K. pygmaea adapted to the high-elevation environment on the Tibetan Plateau by aggressively accumulating abiotic stress-related metabolites and proteins and by the various life events mediated by proteins. Based on the species'lexible physiological and biochemical processes, we surmised that environment change has only a slight

  11. Application of CCA for study on modern lake diatoms and environment in the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    羊向东; 王苏民; 夏威岚; 李万春

    2001-01-01

    The relations between lake surface sediment diatoms and water environmental variables were revealed effectively by use of a new multivariate canonical correspondence analysis (CCA) based on 45 lakes in the Tibetan Plateau. Water depth, conductivity, Cl-, Mg2+, K+ and pH, identified from 12 contemporary water environmental variables, can significantly and independently explain the diatom distributions (p<0.05). The first two axes (λ1=0.34, λ2=0.27) capture 16.1% of the variance in the species data, and account for 57.4% of the variance in diatom-environment relationship. The deletion of redundant environmental variables and unusual samples do not influence the explanation to diatom data. The final CCA result indicates that the water depth and the salinity are the two important environmental gradients and influence the diatom distribution in the plateau lakes. The water depth correlates with axis 1, while conductivity, Cl-, Mg2+ and K+, indicating the direction of salinity changes, corr

  12. Mineral deposits of the Silica plateau – evaluation of selected geological factors of the environment

    Directory of Open Access Journals (Sweden)

    BalហBartolomej

    2001-12-01

    Full Text Available The Silica plateau is a part of a greatest karst area in the Slovak republic - Protected Landscape Area Slovak karst (CHKO Slovenský kras. Karst areas belong to the most sensitive environments, from the point of view of impacts caused by anthropogenous activities. This area reacts sensitively, disturbing the environmental balance caused by mining of mineral deposits. Three mineral deposits of industrial rocks: one deposit of decorative stone - Silická Brezová and two deposits of building stone – Silická Brezová I and Lipovník, respectively, were registered on January 1-st, 2001 in the territory of the Silica plateau. Some deposits utilized in the past namely two deposits of building raw materials (Hrušov and Krásnohorská Dlhá Lúka and one Pb-Zn ore deposit (Ardovo are also mentioned and evaluated in the paper. From the point of view of economical potential of the area, mineral deposits have a character of geopotentials. However the utilization of deposits represents negative anthropogenous impact. When compared with another forms of optimal and rational utilization of the country, e.g. agriculture, forestry, water management, construction, tourism etc., mineral deposits have a character of geobarriers. This research was carried out in the frame of the VEGA Grant No. 1/6090/1999.

  13. [Study of blood oxygen saturation, heart rate changes and plateau reaction of the Antarctic Kunlun station investigation team in different plateau environments].

    Science.gov (United States)

    Zhao, Shun-yun; Wu, Xin-min; Guo, Ya-min; Zhang, Shu-shun; An, Yan-ming; Li, Bing; Wang, Hao

    2013-06-11

    To explore the blood oxygen saturation and heart rate changes of the Antarctic explorers. During August 2010 to April 2011, the changes in blood oxygen saturation, heart rate and plateau reaction of 16 Antarctic expedition team in different plateau environments (Tibetan plateau versus Antarctic plateau) were monitored with the noninvasive pulse oximeter MD300-C. The extent of acute mountain sickness was determined according to the Lake Louise Consensus acute mountain reaction symptom scores and judgment method. The changes of blood oxygen saturation, heart rate at different altitudes of 110, 3650, 4300 m (96.8% ± 1.2%,89.1% ± 1.2%, 86.1% ± 2.0%, (75.0 ± 5.4) times/min, (104.0 ± 4.3) times/min, (113.0 ± 5.2) times/min,F = 214.155, 240.088,both P blood oxygen saturation, heart rate at different altitudes of 2000, 2500, 3000, 3500 and 4087 m(91.9% ± 1.3%,90.5% ± 1.3%,87.6% ± 1.4%,85.0% ± 1.8%,81.5% ± 2.2%, (85.9 ± 3.2) times/min, (90.6 ± 2.8) times/min, (97.8 ± 4.1) times/min, (102.0 ± 3.4) times/min, (106.3 ± 3.9) times/min, F = 105.418, 90.174, both P blood oxygen saturation and heart rate were both correlated with the risk of altitude sickness (r = -0.446 and 0.565, both P heart rate of the Antarctic explorers. And with the increases of altitude, the risk of altitude sickness gradually increases.

  14. Research on EHN additive on the diesel engine combustion characteristics in plateau environment

    Science.gov (United States)

    Sun, Zhixin; Li, Ruoting; Wang, Xiancheng; Hu, Chuan

    2017-03-01

    Aiming at the combustion deterioration problem of diesel engine in plateau environment, a bench test was carried out for the effects of EHN additive on combustion characteristics of the diesel engine with intake pressure of 0.68 kPa. Test results showed that with the full load working condition of 1 400 r/min: Cylinder pressure and pressure uprising rate decreased with EHN additive added in, mechanical load on the engine could be relieved; peak value of the heat release rate decreased and its occurrence advanced, ignition delay and combustion duration were shortened; cylinder temperature and exhaust gas temperature declined, thermal load on the engine could be relieved, output torque increased while specific oil consumption decreased, and effective thermal efficiency of diesel engine increased.

  15. Characterizing stellar and exoplanetary environments

    CERN Document Server

    Khodachenko, Maxim

    2015-01-01

    In this book an international group of specialists discusses studies of exoplanets subjected to extreme stellar radiation and plasma conditions. It is shown that such studies will help us to understand how terrestrial planets and their atmospheres, including the early Venus, Earth and Mars, evolved during the host star’s active early phase. The book presents an analysis of findings from Hubble Space Telescope observations of transiting exoplanets, as well as applications of advanced numerical models for characterizing the upper atmosphere structure and stellar environments of exoplanets. The authors also address detections of atoms and molecules in the atmosphere of “hot Jupiters” by NASA’s Spitzer telescope. The observational and theoretical investigations and discoveries presented are both timely and important in the context of the next generation of space telescopes. 
 The book is divided into four main parts, grouping chapters on exoplanet host star radiation and plasma environments, exoplanet u...

  16. ECO-ENVIRONMENT CHANGE AND SOIL EROSION PROCESS IN THE RECLAIMED FORESTLAND OF THE LOESS PLATEAU

    Institute of Scientific and Technical Information of China (English)

    ZHA Xiao-chun; TANG Ke-li

    2003-01-01

    Serious soil erosion has made the eco-environment fragile in the Loess Plateau. Based on the 10-year da-ta observed from 1989 to 1998 in the Ziwuling Survey Station in loess hilly region, the eco-environment change and soil erosion process in reclaimed forestland were studied in this paper. The results showed that the intensity of man-made soil erosion caused by forestland reclamation was 1000 times more than that of the natural erosion. From the analysis of soil physical and mechanical properties, in the 10th year after forestland was reclaimed, the clay content and physical clay content decreased 2.74 percentage point and 3.01 percentage point respectively, the >0.25mm water-stable aggregate content decreased 31.59 percentage point, the soil bulk density increased and soil shear strength de-creased, all of which were easier to cause soil erosion. The correlation analysis showed that >0.25mm waterstable ag-gregate content was the key factor affecting soil erosion, and the secondary factors were soil coarse grain and soil shear strength. The relation between the >0.25mm waterstable aggregate content, the soil sheer strength and the soil erosion intensity were analyzed, which showed that the first year and the seventh erosion year were the turn years of the soil erosion intensity after the forestland was reclaimed, revealed that the change ofeco-environment was the main cause to accelerate soil erosion, and the worse environment caused soil erosion to be serious rapidly.

  17. Persistence of Carbonate Platform Environments in Central Mexico during the Oceanic Anoxic Event 2: impact of the Carribean Plateau?

    Science.gov (United States)

    Bomou, Brahimsamba; Adatte, Thierry; Föllmi, Karl; Arnaud-Vanneau, Annie; Fleitmann, Dominik

    2010-05-01

    The Cenomanian-Turonian Oceanic Anoxic Event 2 is described as an interruption of normal pelagic sediment deposition by several distinct intervals of widespread oceanic anoxia (Schlanger & Jenkyns, 1976; Jenkyns, 1980; Arthur et al., 1990) characterized by black shales deposition coinciding with a positive shift in carbon isotope excursion. Some authors show a relationship between OAEs and massive volcanic events associated with the emplacement of large igneous provinces (LIPs) and sea floor spreading at mid-ocean ridges (Kuroda et al., 2007; Snow et al., 2005). High metal abundance anomalies recorded in pelagic sections (e.g. Pueblo, Colorado) coincide with the massive volcanism that built the Carribean plateau (around 93-94 Ma), associated with the onset of OAE 2 (Snow et al., 2005). Mort et al., (2007) demonstrate that the onset of the OAE 2 was triggered by a short-lived but significant increase in phosphorus burial. The bottom waters became anoxic and switched from being a P sink to a P source, sustaining the productivity in a positive feedback loop. However, the behaviour of phosphorus and trace metals at larger scale, in different paleogeography and paleodepht is still poorly known. The Axaxacualco and Baranca el Cañon sections, located at the Guerrero-Morelos carbonate platform in southern Mexico exhibit a fully correlateable d13C curves. In the distal part of the carbonate platform at Axaxacualco, the maximum d13C positive excursion coincides with oligotrophic carbonate platform environments supported by low concentrations in P and characterized by abundant and diversified benthic microfauna and rudists. The impact of OAE appears may be more significant in the proximal part of the carbonate platform at Barranca, characterized by the deposition of thick laminated microbialites indicative of mesotrophic conditions. The Morelos Carbonate platform with oligotrophic to mesotrophic conditions was persistent throughout the entire OAE2 in Central Mexico despite

  18. Genetic Convergence in the Adaptation of Dogs and Humans to the High-Altitude Environment of the Tibetan Plateau

    Science.gov (United States)

    Wang, Guo-Dong; Fan, Ruo-Xi; Zhai, Weiwei; Liu, Fei; Wang, Lu; Zhong, Li; Wu, Hong; Yang, He-Chuan; Wu, Shi-Fang; Zhu, Chun-Ling; Li, Yan; Gao, Yun; Ge, Ri-Li; Wu, Chung-I; Zhang, Ya-Ping

    2014-01-01

    The high-altitude hypoxic environment represents one of the most extreme challenges for mammals. Previous studies of humans on the Tibetan plateau and in the Andes Mountains have identified statistical signatures of selection in different sets of loci. Here, we first measured the hemoglobin levels in village dogs from Tibet and those from Chinese lowlands. We found that the hemoglobin levels are very similar between the two groups, suggesting that Tibetan dogs might share similar adaptive strategies as the Tibetan people. Through a whole-genome sequencing approach, we have identified EPAS1 and HBB as candidate genes for the hypoxic adaptation on the Tibetan plateau. The population genetic analysis shows a significant convergence between humans and dogs in Tibet. The similarities in the sets of loci that exhibit putative signatures of selection and the hemoglobin levels between humans and dogs of the same environment, but not between human populations in different regions, suggests an extraordinary landscape of convergent evolution between human beings and their best friend on the Tibetan plateau. PMID:25091388

  19. "Greatest lake period"and its palaeo-environment on the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The“greatest lake perion”means that the lakes are in the stage of their maximum areas.As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau,the lake areas during the “greatest lake period”may be inferred by the last highest lake shorelines.They are several,even tens times larger than that at present.According to the analyses of tens of lakes on the Plateau,most dating data fell into the range of 40-25 ka BP,some lasted to 20 ka BP.It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation.The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period.

  20. Late Cenozoic Geology and Paleo-environment Change in the Eastern Edge of Qinghai-Xizang Plateau

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zhizhong; MIAO Qi; JIANG Fuchu; QIAO Yansong; WANG Shubing; YAO Haitao; WANG Yan; LI Chaozhu; FU Jianli; LIU Zongxiu; LI Mingze

    2008-01-01

    There are late Cenozoic lacustrine deposits and loess and red clay and moraines in eastern edge of the Qinghai-Xizang Plateau. Various genetic sediments recorded rich information on late Cenozoic paleo-environment changes. Xigeda lacustrine formed during 4.2 Ma B.P.-2.6 Ma B.P. There were 9 periodic warm-cold alternations. Eolian deposition in western Sichuan began at 1.15 Ma B.P. The loess-soil sequences recorded successively 14 paleo-monsoon climate cycles. Laterite in Chengdu plain recorded 5 stages of paleoclimatic stages since 1.13 Ma B.P. There was an old glacial period of 4.3 Ma B.P. In eastern Qinghai-Xizang Plateau. During Quaternary, there are 5 extreme paleoclimatic events corresponding with 5 glaciations.

  1. Agriculture sustainability in a sensitive environment--a case analysis of Loess Plateau in China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Loess Plateau, an arid and semi-arid region in Northwest China, is well-known for its most serious soil erosion in terms of sediment yield each year. Soil erosion, which is intensified by agricultural activities, is the major factor influencing sustainable agriculture development in this region. It reduces productivity by removing nutrients and especially reducing water availability that is essential for crop production in the area. It also brings about off-site costs by demanding more efforts for maintenance of banks and dams along Yellow River through raising the riverbed with sediment. Climate is capricious and extreme weather conditions occur frequently, which impairs normal agricultural production with erosion and also decrease of water availability. Extensive way of farming still dominates on the Loess Plateau, which cannot produce satisfying economic results and needs to be improved or altered. Conventional agricultural production pattern needs to be reconsidered for husbandry has not been granted its due position. Agriculture is the backbone of economy. Poor agricultural production impedes economic development and vice versa, backward economy also influences the advancement of agriculture. Besides a large population, education status of farmers is another threshold that requires being resolved for a sustainable agriculture.Although conventional agriculture has been practiced there for more than 5000 years, now it cannot meet the demand for food and fiber by the increasing population and some of its farming practices are contributing to environmental degradation directly or indirectly and can sustain no longer. Agriculture on Loess Plateau needs to find its own way of sustainability. To work toward a sustainable agriculture, chances and challenges both indwell on Loess Plateau.

  2. 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.

  3. Characterization of dissolved organic matter fractions from Lake Hongfeng, Southwestern China Plateau

    Institute of Scientific and Technical Information of China (English)

    WANG Liying; WU Fengchang; ZHANG Runyu; LI Wen; LIAO Haiqing

    2009-01-01

    With XAD-series and ion exchange resins, dissolved organic matter (DOM) from Lake Hongfeng in Southwestern China Plateau was isolated into 6 fractions, i.e., humic acid (HA), fulvic acid (FA), hydrophobic neutrals (HON), hydrophilic acids (HIA), hydrophilic bases (HIB) and hydrophilic neutrals (HIN). Those fractions were characterized by high performance size exclusion chromatography, fluorescence spectroscopy and UV absorbance. Among the 6 fractions, FA was predominant and accounted for 51% of the total DOM. The hydrophobic fractions had larger molecular weight (1688--2355 Da) than hydrophilic fractions (1338--1928 Da). A strong correlation was observed between specific UV absorbance at 280 nm, E2/E3 (absorbance at 250 nm to 365 nm), and the molecular weight for DOM fractions. UV-Vis fulvic-like fluorescence peaks were found in all fractions. Protein-like fluorescence peaks existed in HON may indicate that microbial activity was severely in Lake Hongfeng. There was a significant relationship between fluorescence intensities and specific UV absorbance at 254 nm for those DOM fractions, suggesting their similar luminescence characteristics. The values of fluorescence index (?450/500) indicated that hydrophobic fractions may derive from terrestrial sources, in contrast to the hydrophilic fractions from microbial and terrestrial origins. Those results suggest that there were inter-relationships between molecular weight, fluorescence and absorbance characteristics, and also subtle consistencies between the hydrophilic and hydrophobic properties and sources for the 6 fractions from Lake Hongfeng.

  4. Characterizing two types of transient intraseasonal oscillations in the Eastern Tibetan Plateau summer rainfall

    Science.gov (United States)

    Yang, Jing; Bao, Qing; Wang, Bin; He, Haozhe; Gao, Miaoni; Gong, Daoyi

    2016-05-01

    During summer, the intraseasonal disturbances over the Eastern Tibetan Plateau (ETP) can initiate development of severe weather system downstream. Previous studies yielded inconsistent results on the intraseasonal variability (ISV) of summer rainfall in terms of periodicity, genesis process and propagation pathway over the EPT based on small samples. In this study, we detected two dominant peaks of transient ISV, centered on quasi-biweekly (12-24) days (QBW) and quasi-9 (8-11) days using daily rainfall data over the ETP during the period of 1992-2012. Composite analysis revealed that the two ISVs were predominantly associated with the non-stationary wave trains, which traveled along different pathways. For the QBW, its mid-latitude wave train featured a upper-level southeastward migration, originating in Northern Europe and traveling via the East European Plain, the Ural Mountains, Lake Balkhash-Lake Baikal, the Mongolian Plateau, and then continued southward to the ETP and South Asia; and its tropical wave train was characterized with a northwestward/northward migration in low-level, starting from the Philippine Sea (PS)-South China Sea (SCS) region, moving over northern Bay of Bengal-SCS region, and arriving over the southern fridge of TP and southern China. In contrast, for quasi-9-day, the most significant mid-latitudes variability featured an eastward propagating upper-level wave train, originating from Western Europe, passing across the Mediterranean, the Black and Caspian seas, arriving over the TP, and moving towards East Asia; and the most evident tropical variability exhibited a clear northwestward/westward migration of a low-level wave train, originating from PS, passing over Taiwan, and subsequently moving towards southeastern China. Their different spatiotemporal features of associated wave trains caused their distinct linkages with eastern China rainfall anomalies. A "meridional pattern" with a giant Ural Mountain Ridge was the most remarkable

  5. Characterizing two types of transient intraseasonal oscillations in the Eastern Tibetan Plateau summer rainfall

    Science.gov (United States)

    Yang, Jing; Bao, Qing; Wang, Bin; He, Haozhe; Gao, Miaoni; Gong, Daoyi

    2017-03-01

    During summer, the intraseasonal disturbances over the Eastern Tibetan Plateau (ETP) can initiate development of severe weather system downstream. Previous studies yielded inconsistent results on the intraseasonal variability (ISV) of summer rainfall in terms of periodicity, genesis process and propagation pathway over the EPT based on small samples. In this study, we detected two dominant peaks of transient ISV, centered on quasi-biweekly (12-24) days (QBW) and quasi-9 (8-11) days using daily rainfall data over the ETP during the period of 1992-2012. Composite analysis revealed that the two ISVs were predominantly associated with the non-stationary wave trains, which traveled along different pathways. For the QBW, its mid-latitude wave train featured a upper-level southeastward migration, originating in Northern Europe and traveling via the East European Plain, the Ural Mountains, Lake Balkhash-Lake Baikal, the Mongolian Plateau, and then continued southward to the ETP and South Asia; and its tropical wave train was characterized with a northwestward/northward migration in low-level, starting from the Philippine Sea (PS)-South China Sea (SCS) region, moving over northern Bay of Bengal-SCS region, and arriving over the southern fridge of TP and southern China. In contrast, for quasi-9-day, the most significant mid-latitudes variability featured an eastward propagating upper-level wave train, originating from Western Europe, passing across the Mediterranean, the Black and Caspian seas, arriving over the TP, and moving towards East Asia; and the most evident tropical variability exhibited a clear northwestward/westward migration of a low-level wave train, originating from PS, passing over Taiwan, and subsequently moving towards southeastern China. Their different spatiotemporal features of associated wave trains caused their distinct linkages with eastern China rainfall anomalies. A "meridional pattern" with a giant Ural Mountain Ridge was the most remarkable

  6. Chemical characterization of garnets from Garnet Ridge, northern Arizona in the Colorado Plateau

    Science.gov (United States)

    Itaru, K.; Ogasawara, Y.

    2011-12-01

    Garnet crystals with diverse chemistries and their origins have occurred at Garnet Ridge in northern Arizona, Colorado Plateau. The garnet grains occur as small grains (2-5mm φ) scattering on weathered late Jurassic red mudstone, very large grained single crystal (1 to several cm), and major constituent minerals of eclogite and other garnet-bearing xenoliths in kimberlitic diatreme. The important discovery of coesite-bearing lawsonite eclogite, which is one of the source rocks of garnets, has been reported by Usui et al. (2005), and their zircon ages (81 to 33 Ma) suggest that the lawsonite eclogite was a product of subduction of the Fallaron plate underneath the Colorado Plateau. We collected several kinds of garnet grains with various origins and of xenoliths, and clarified the chemical characteristics of these garnets with an electron microprobe (JXA-8900 WDS mode). The garnet samples were classified into 6 groups: (A) scattered grains of reddish to purplish garnet (2-5 mm φ), (B) large-grained reddish brown garnet, (C) garnet in an eclogite xenolith. (D) garnet in unknown xenolith A, (E) garnet in unknown xenolith B, (F) garnet in garnet-clinopyroxene rock xenolith (strongly altered). The results of microprobe analyses showed the large difference in each garnet type on Prp-Alm-Grs triangular diagram. The garnet chemistries were as follows: (1) Type A garnets were relatively Prp-rich but have a wide range in Prp component. The Cr2O3 contents (max. 4 wt.%) divided this type into two groups. (2) Type-B garnets were plotted near the center of the triangle and did not show clear chemical zonation. (3) Type-C garnets have Alm-rich composition and were low in Prp. They show chemical zonation of Pyr and Grs components (MgO:1.4 to 5.4 wt.%, and CaO: 14.0 to 5.6 wt.% both from core to rim). Clinopyroxene is omphacite. (4) Type D garnets were plotted on Alm-Grs join (Grs61-71Alm23-35And5-7). (5) Type E garnets are characterized by very low Grs-components and were

  7. The Third Pole Environment Programme (TPE): A new base for the processes study of atmospheric physics and environment over the Tibetan Plateau and surrounding regions

    Science.gov (United States)

    Ma, Yaoming

    2016-04-01

    The Tibetan Plateau, with the most prominent and complicated terrain on the globe and an elevation of more than 4000 m on average above sea leave (msl), is often called the "Third Pole" due to its significance parallel with Antarctica and the Arctic. The exchange of energy, water vapor and some greenhouse gases between land surface and atmosphere over the Tibetan Plateau and the surrounding regions play an important role in the Asian monsoon system, which in turn is a major component of both the energy and water cycles of the global climate system. Supported by the Chinese Academy of Sciences and some international organizations, a Third Pole Environment (TPE) Research Platform (TPEP) is now implementing over the Tibetan Plateau and surrounding region. The background of the establishment of the TPEP, the establishing and monitoring plan of long-term scale (5-10 years) of the TPEP will be shown firstly. Then the preliminary observational analysis results, such as the characteristics of land surface heat fluxes, CO2 flux and evapotranspiration (ET) partitioning (diurnal variation, inter-monthly variation and vertical variation etc), aerosol optical properties between southern and northern sides of the Himalayas, the characteristics of atmospheric and soil variables, the structure of the Atmospheric Boundary Layer (ABL) and the turbulent characteristics have also been shown in this study.

  8. S-wave crustal and upper mantle's velocity structure in the eastern Tibetan Plateau-Deep environment of lower crustal flow

    Institute of Scientific and Technical Information of China (English)

    WANG ChunYong; Paul SILVER; L(U) Hai; LOU ZhiYong; WU JianPing; CHANG LiJun; DAI ShiGui; YOU HuiChuan; TANG FangTou; ZHU LuPei

    2008-01-01

    A teleseismic profile consisting of 26 stations was deployed along 30°N latitude in the eastern Tibetan Plateau. By use of the inversion of P-wave receiver function, the S-wave velocity structures at depth from surface to 80 km beneath the profile have been determined. The inversion results reveal that there is significant lateral variation of the crustal structure between the tectonic blocks on the profile. From Linzhi north of the eastern Himalayan Syntaxis, the crust is gradually thickened in NE direction; the crustal thickness reaches to the maximum value (~72 km) at the Bangong-Nujiang suture, and then decreased to 65 km in the Qiangtang block, to 57-64 km in the Bayan Har block, and to 40-45 km in the Sichuan Basin. The eastern segment of the teleseismic profile (to the east of Batang) coincides geographically with the Zhubalong-Zizhong deep seismic sounding profile carried out in 2000, and the S-wave velocity structure determined from receiver functions is consistent with the P-wave velocity structure obtained by deep seismic sounding in respect of the depths of Mono and major crustal interfaces. In the Qiangtang and the Bayan Har blocks, the lower velocity layer is widespread in the lower crust (at depth of 30-60 km) along the profile, while there is a normal velocity distribution in lower crust in the Sichuan Basin. On an average, the crustal velocity ratio (Poisson ratio) in tectonic blocks on the profile is 1.73 (σ= 0.247) in the Lhasa block, 1.78 (σ= 0.269) in the Banggong-Nujiang suture, 1.80 (σ = 0.275) in the Qiangtang block, 1.86 (σ= 0.294) in the Bayan Har blocks, and 1.77 (σ=0.265) in the Yangtze block, respectively. The Qiangtang and the Bayan Har blocks are characterized by lower S-wave velocity anomaly in lower crust, complicated Moho transition, and higher crustal Poisson ratio,indicating that there is a hot and weak medium in lower crust. These are considered as the deep environment of lower crustal flow in the eastern Tibetan Plateau

  9. Quality characterization of Cretaceous coal from the Colorado Plateau coal assessment study area, 2000 (cpchmg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This is a shapefile and ARC/INFO point coverage of coal geochemistry in the Colorado Plateau. This GIS layer was created from the U.S. Geological Survey's USCHEM...

  10. Characterizations of geothermal springs along the Moxi deep fault in the western Sichuan plateau, China

    Science.gov (United States)

    Qi, Jihong; Xu, Mo; An, Chengjiao; Wu, Mingliang; Zhang, Yunhui; Li, Xiao; Zhang, Qiang; Lu, Guoping

    2017-02-01

    Abundant geothermal springs occur along the Moxi fault located in western Sichuan Province (the eastern edge of the Qinghai-Tibet plateau), highlighted by geothermal water outflow with an unusually high temperature of 218 °C at 21.5 MPa from a 2010-m borehole in Laoyulin, Kangding. Earthquake activity occurs relatively more frequently in the region and is considered to be related to the strong hydrothermal activity. Geothermal waters hosted by a deep fault may provide evidence regarding the deep underground; their aqueous chemistry and isotopic information can indicate the mechanism of thermal springs. Cyclical variations of geothermal water outflows are thought to work under the effect of solid earth tides and can contribute to understanding conditions and processes in underground geo-environments. This paper studies the origin and variations of the geothermal spring group controlled by the Moxi fault and discusses conditions in the deep ground. Flow variation monitoring of a series of parameters was performed to study the geothermal responses to solid tides. Geothermal reservoir temperatures are evaluated with Na-K-Mg data. The abundant sulfite content, dissolved oxygen (DO) and oxidation-reduction potential (ORP) data are discussed to study the oxidation-reduction states. Strontium isotopes are used to trace the water source. The results demonstrate that geothermal water could flow quickly through the Moxi fault the depth of the geothermal reservoir influences the thermal reservoir temperature, where supercritical hot water is mixed with circulating groundwater and can reach 380 °C. To the southward along the fault, the circulation of geothermal waters becomes shallower, and the waters may have reacted with metamorphic rock to some extent. Our results provide a conceptual deep heat source model for geothermal flow and the reservoir characteristics of the Moxi fault and indicate that the faulting may well connect the deep heat source to shallower depths. The

  11. Attribution of Runoff Change for the Xinshui River Catchment on the Loess Plateau of China in a Changing Environment

    Directory of Open Access Journals (Sweden)

    Guoqing Wang

    2016-06-01

    Full Text Available Stream flow plays a crucial role in the environment, society, and the economy, and identifying the causes of changes in runoff is important to understanding the impact of climate change and human activity. This study examines the variation trends in recorded runoff for the Xinshui River, a tributary of the Yellow River on the Loess Plateau, and uses hydrological simulations to investigate how climate change and human activity have contributed to those trends. Results show that the recorded runoff at the Daning station on the Xinshui River declined significantly from 1955–2008 with an abrupt change occurring in 1973. The Simplified Water Balance Model (SWBM simulates monthly discharge well with a Nash–Sutcliffe efficiency (NSE coefficient of 78% and a relative error of volumetric fit (RE of 0.32%. Runoff depth over the catchment in 1973–2008 fell by 25.5 mm relative to the previous period, with human activity and climate change contributing 60.6% and 39.4% of the total runoff reduction, respectively. However, the impacts induced by climate change and human activities are both tending to increase. Therefore, efforts to improve the ecology of the Loess Plateau should give sufficient attention to the impacts of climate change and human activity.

  12. Morphostructural characterization of the western edge of the Huila Plateau (SW Angola), based on remote sensing techniques

    Science.gov (United States)

    Lopes, Fernando Carlos; Pereira, Alcides José; Mantas, Vasco Manuel; Mpengo, Horácio Kativa

    2016-05-01

    Recognition of the main morphostructural features of the western edge of the Huila Plateau (SW Angola) can be done by using remote sensing techniques associated with field work. A digital elevation model (DEM) of the area was built for this purpose. This model is based on altimeter data acquired from the Aster sensor, on which image processing techniques such as enhancement techniques, contrast change and filtering were applied. Other techniques, such as RGB colour composition, were also tested. The processed satellite images were interpreted by visual process and the results were then compared with available geological maps (scale 1: 1 000 000). To facilitate both analysis and interpretation, the edge of the plateau was divided into three sectors: northern (or Chongoroi Edge), central (or Humpata Edge) and southern (or Oncocua Edge). For each sector, the main morphological aspects and main lineament systems were identified and characterized. In the specific case of the central sector, these parameters were also confirmed by field work. This study shows that the morphology of the western edge of the plateau is dominated by N50°W-N60°W, N60°E and N-S trending main tectonic systems. These results have important implications in terms of geological mapping and regional tectonics as well as in land-use planning and other areas, such as hydrogeology or geotechnics.

  13. Characterizing the dynamics of soil organic carbon in grasslands on the Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Carbon dynamics of grasslands on the Qinghai-Tibetan Plateau may play an important role in regional and global carbon cycles. The CENTURY model (Version 4.5) is used to examine temporal and spatial variations of soil organic carbon (SOC) in grasslands on the Plateau for the period from 1960 to 2002. The model successfully simulates the dynamics of aboveground carbon and soil surface SOC at the soil depth of 0-20 cm and the simulated results agree well to the measurements. Examination of SOC for eight typical grasslands shows different patterns of temporal variation in different ecosystems in 1960-2002. The extent of temporal variation increases with the increase of SOC of ecosystem. SOC increases first and decreases quickly then during the period from 1990 to 2000. Spatially, SOC density obtained for the equilibrium condition declines gradually from the southeast to the northwest on the plateau and showed a high heterogeneity in the eastern plateau. The results suggest that (i) SOC den-sity in the alpine grasslands shows remarkable response to climate change during the 42 years, and (ii) the net carbon exchange rate between the alpine grassland ecosystems and the atmosphere increases from 1990 to 2000 as compared with that before 1990.

  14. Characterizing the dynamics of soil organic carbon in grasslands on the Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    ZHANG YongQiang; TANG YanHong; JIANG Jie; YANG YongHui

    2007-01-01

    Carbon dynamics of grasslands on the Qinghai-Tibetan Plateau may play an important role in regional and global carbon cycles. The CENTURY model (Version 4.5) is used to examine temporal and spatial variations of soil organic carbon (SOC) in grasslands on the Plateau for the period from 1960 to 2002. The model successfully simulates the dynamics of aboveground carbon and soil surface SOC at the soil depth of 0-20 cm and the simulated results agree well to the measurements. Examination of SOC for eight typical grasslands shows different patterns of temporal variation in different ecosystems in 1960-2002. The extent of temporal variation increases with the increase of SOC of ecosystem. SOC increases first and decreases quickly then during the period from 1990 to 2000. Spatially, SOC density obtained for the equilibrium condition declines gradually from the southeast to the northwest on the plateau and showed a high heterogeneity in the eastern plateau. The results suggest that (i) SOC density in the alpine grasslands shows remarkable response to climate change during the 42 years, and (ii) the net carbon exchange rate between the alpine grassland ecosystems and the atmosphere increases from 1990 to 2000 as compared with that before 1990.

  15. Characterization of the prokaryotic diversity through a stratigraphic permafrost core profile from the Qinghai-Tibet Plateau.

    Science.gov (United States)

    Hu, Weigang; Zhang, Qi; Tian, Tian; Li, Dingyao; Cheng, Gang; Mu, Jing; Wu, Qingbai; Niu, Fujun; An, Lizhe; Feng, Huyuan

    2016-05-01

    Permafrost on the Qinghai-Tibet Plateau is one of the most sensitive regions to climate warming, thus characterizing its microbial diversity and community composition may be important for understanding their potential responses to climate changes. Here, we investigated the prokaryotic diversity in a 10-m-long permafrost core from the Qinghai-Tibet Plateau by restriction fragment length polymorphism analysis targeting the 16S rRNA gene. We detected 191 and 17 bacterial and archaeal phylotypes representing 14 and 2 distinct phyla, respectively. Proteobacteria was the dominant bacterial phylum, while archaeal communities were characterized by a preponderance of Thaumarchaeota. Some of prokaryotic phylotypes were closely related to characterized species involved in carbon and nitrogen cycles, including nitrogen fixation, methane oxidation and nitrification. However, the majority of the phylotypes were only distantly related to known taxa at order or species level, suggesting the potential of novel diversity. Additionally, both bacterial α diversity and community composition changed significantly with sampling depth, where these communities mainly distributed according to core horizons. Arthrobacter-related phylotypes presented at high relative abundance in two active layer soils, while the deeper permafrost soils were dominated by Psychrobacter-related clones. Changes in bacterial community composition were correlated with most measured soil variables, such as carbon and nitrogen contents, pH, and conductivity.

  16. Morphological adaptations of yak (Bos grunniens) tongue to the foraging environment of the Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Shao, B; Long, R; Ding, Y; Wang, J; Ding, L; Wang, H

    2010-08-01

    Using light and scanning electron microscopy, the morphological adaptations of the yak (Bos grunniens) tongue to its foraging environment in the Qinghai-Tibetan Plateau were studied. The tongue of the yak was compared with that of cattle (Bos taurus). Compared with cattle, yak tongues are on average 4 cm shorter (P tongue into the harsh environment. The lingual prominence of yak is greater (P tongue and the upper palate. Filiform, conical, lenticular, fungiform, and vallate papillae were observed on the dorsal surface of the tongues studied; no foliate papillae were observed. The papillae were covered by keratinized epithelium, which was thicker (P epithelium, whereas they are multilayered (2 to 4) in those papillae in cattle. The number of taste buds in each vallate papillae was less (P < 0.001) in the yak than in cattle. Therefore, the gustatory function of the yak was weaker than in cattle. Yaks graze throughout the year on diverse natural grasslands and have evolved morphological characteristics enabling them to consume a wide variety of plant species, thereby better adapting them to the typically harsh characteristics of their pastures.

  17. Evaluation of concordance between environment and economy in Qinghai Lake Watershed, QinghaiTibet Plateau

    Institute of Scientific and Technical Information of China (English)

    WANG Jianhua; TIAN Jinghan; LI Xiaoyan; MA Yujun; YI Wanjuan

    2011-01-01

    Qinghai Lake Watershed (QLW) is a hot place of a series of ecological restoration and environmental remediation programs nowadays.However,little information is available on change of ecosystem service and economic practice in this area.As ecosystem service and natural capital are closely related with social and economic development,an index of concordance between environment and economy (ICEE) has been proposed to compare the annual variation rate of ecosystem service value (REsv) with that of gross domestic product (RGDP).Using this Index,we have assessed concordance between environment and economy (CEE) for the QLW in the period 1977-2004.The result showed that from 1977 to 2004,the ecosystem service value in the QLW descended from 128.81 x108 yuan to 127.32x108 yuan;In contrast,the GDP increased from 0.931x108 yuan to 8.856x108 yuan.The values of the IGEE were -1.14,-0.22,and -0.14 in the stages of 1977-1987,1987-2000 and 2000-2004,respectively.The result indicated that during the first stage 1977-1987,the relationship between environment and economy in the QLW was not concordant but at a high conflict; from 1987 to 2004,there was a low conflict between environment and economy,and the CEE appeared to increase slowly.Analysis of the assessment results showed that the national policies and industrial adjustment practice play an important role in the CEE changes.

  18. Institute of Tibetan Plateau Research

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ The Tibetan Plateau (Qinghai-Xizang Plateau)is a unique geological-geographical unit on Earth, an ideal region for studies into the formation and evolution of the lithosphere and the dynamic mechanism of the earth crust. The uplifting of the Plateau exerts profound influence upon the evolution and differentiation of the natural environment of the plateau itself, its adjacent regions and the Northern Hemisphere. As a unique natural geographical unit, the Plateau holds a special status in the whole globe due to its special natural environment and ecosystems, which is also in close relation to global environmental change.The significance of the Plateau research should be recognized not only in the fundamental research fields of geo-sciences and biology, but also in its application to resource exploitation, environmental protection and sustainable development of the Plateau region.

  19. Erosion environment in the sediment-rich area on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on the investigation and analysis of characteristics of precipitation, natural environment, socio-economic factors and soil erosion, this paper indicates that the precipitation is the main driving force for the soil erosion in the sediment-rich area, its variability determines the characteristics of soil and water loss; the natural conditions such as the drainage systems, geological and topographic features, the composition of soil and land surface materials, vegetation and climate determine the seriousness of soil and water loss; irrational socio-economic activities of human beings usually accelerated soil and water loss; meanwhile, the low preservation rate and inferiority of soil and water conservation measures made it impossible to make rapid progress on soil and water loss control. Furthermore, the characteristics of erosion environment endowed this area with more sediment that is the main reason for the flooding disasters by the Yellow River. Therefore, more emphasis should be placed on the enhancement of soil and water conservation. The soil loss prediction models will provide scientific basis for the planning of soil and water conservation, the designing of soil and water conservation measures and the valuation of effects of soil and water loss control. According to the analysis of the previous studies on soil loss prediction, and the water-sediment variation features, it is thought that study on soil loss prediction under various rainfall conditions and soil-water conservation measures should be carried out.

  20. Trace element geochemistry and tectonic characterization of the granulite facies rocks from Southwest Obudu Plateau, southeastern Nigeria

    Institute of Scientific and Technical Information of China (English)

    Ekere E. Ukwang; Barth N. Ekwueme

    2009-01-01

    The trace elements characteristics of the migmatitic gneisses (biotite-garnet- and hornblende-biotite), granulite facies rocks (charnockitic gneisses) and meta-peridotite in the area of Southwest Obudu Plateau indicate that the area exhibits a high degree of geochemical variability. Compatible trace elements (Ni and Cr) are comparatively high in the granulite facies rocks and meta-peridotite. Ni ranges from 28×10-6 to 266×10-6 whilst Cr ranges from 62×10-6 to 481×10-6 for the granulite facies rocks (charnockitic gneisses), and for the meta-peridotite Ni varies between 2045×10-6 and 2060×10-6. Incompatible trace elements show a higher variability in these rocks. The rocks in the area of Southwest Obudu Plateau generally are characterized by the high concentrations of Ba, Ce, Sr, Rb, Ga, Ni, Cr, Co, Zr, Pr and moderate concentrations of Cu, Sm and Th. The available data show that the charnockitic gneisses are of lower crustal origin. The enrichment of the meta-peridotite in compatible trace elements suggests the primitive mantle would be the source region, with slight contamination during ascent. These diverse origins collaborate the tectonic setting of the area as shown by discrimination diagrams. The diverse tectonic settings range from arc to collisional. Alkaline to sub-alkaline magmatism in the area was probably contemporaneous with the tectonic events that occurred in the area during the Proterozoic.

  1. Black carbon aerosol characterization in a remote area of Qinghai-Tibetan Plateau, western China.

    Science.gov (United States)

    Wang, Qiyuan; Schwarz, J P; Cao, Junji; Gao, Rushan; Fahey, D W; Hu, Tafeng; Huang, R-J; Han, Yongming; Shen, Zhenxing

    2014-05-01

    The concentrations, size distributions, and mixing states of refractory black carbon (rBC) aerosols were measured with a ground-based Single Particle Soot Photometer (SP2), and aerosol absorption was measured with an Aethalometer at Qinghai Lake (QHL), a rural area in the Northeastern Tibetan Plateau of China in October 2011. The area was not pristine, with an average rBC mass concentration of 0.36 μg STP-m(-3) during the two-week campaign period. The rBC concentration peaked at night and reached the minimal in the afternoon. This diurnal cycle of concentration is negatively correlated with the mixed layer depth and ventilation. When air masses from the west of QHL were sampled in late afternoon to early evening, the average rBC concentration of 0.21 μg STP-m(-3) was observed, representing the rBC level in a larger Tibetan Plateau region because of the highest mixed layer depth. A lognormal primary mode with mass median diameter (MMD) of ~175 nm, and a small secondary lognormal mode with MMD of 470-500 nm of rBC were observed. Relative reduction in the secondary mode during a snow event supports recent work that suggested size dependent removal of rBC by precipitation. About 50% of the observed rBC cores were identified as thickly coated by non-BC material. A comparison of the Aethalometer and SP2 measurements suggests that non-BC species significantly affect the Aethalometer measurements in this region. A scaling factor for the Aethalometer data at a wavelength of 880 nm is therefore calculated based on the measurements, which may be used to correct other Aethalometer datasets collected in this region for a more accurate estimate of the rBC loading. The results present here significantly improve our understanding of the characteristics of rBC aerosol in the less studied Tibetan Plateau region and further highlight the size dependent removal of BC via precipitation.

  2. Characterization and possible origins of isolated douglas fir stands on the Colorado Plateau

    Energy Technology Data Exchange (ETDEWEB)

    Spence, J.R. [National Park Service, Page, AZ (United States)

    1995-09-01

    The floristic composition of several isolated stands of Pseudotsuga menziesii on the Colorado Plateau is compared. All occurred between 1700-2000 meters, which was about 300-500 meters below typical lower limits for the species. Most stands showed evidence of reproduction and recruitment. A small widespread group of species existed that was common to all stands, but beta diversity was high. A preliminary analysis of possible origins of the stands suggested that they are relictual from the late Wisconsin or early Holocene. Bird-dispersed species were less prevalent than expected compared with existing high elevation conifer forests. These stands represent important resources for Quaternary research, but are extremely vulnerable to human-caused disturbances. It is recommended that they be provided protection from disturbance through appropriate management activities of the various land management agencies.

  3. Terrestrial mollusk evidence for the origin and sedimentary environment of the Late Tertiary Red Clay Formation in the Loess Plateau, China

    Institute of Scientific and Technical Information of China (English)

    PEI Yunpeng; WU Naiqin; LI Fengjiang

    2004-01-01

    The origin and sedimentary environment of the Late Tertiary (Neogene) Red Clay Formation in northern China had long been controversial. A new mollusk record from the Xifeng red clay (red-earth) sequence in the central Loess Plateau provides the biological evidence for addressing questions of its origin and environmental implication. The study of composition and preservation condition of seventy mollusk fossil assemblages reveals the initial ecological condition of the red clay formation, avoiding the effect of post-deposited alteration. The result shows that all of identifiable mollusk species are composed of terrestrial taxa, most of them are the common species found in the overlying Quaternary loess-paleosol sequence. Most of fossil individuals preserved in the red clay strata are in living conditions based on the investigation of fieldwork, indicating the original population. Thus, the mollusk fossil assemblages can be used as an indicator of primary environment of the red clay formation. The mollusk record from the Xifeng red clay sequence supports the view that the red clay is an aeolian origin, similar to the overlying Quaternary loess deposits. Our data also reveal the history of environmental changes at Xifeng from 6.2-2.4 Ma, which is coupled in phase with the formation and development of the Arctic ice sheets and the process of the Tibetan Plateau uplift. Both may be the major cause and forcing mechanisms of the late Tertiary environmental changes in the Loess Plateau.

  4. Characterizing changes in ecosystem service values in China's eastern Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    JinChang Li; HaiXia Liu; ZhiZhu Su; Yong Liu; YongGang Yang

    2015-01-01

    Human activities such as the implementation of ecological protection projects and expansion of construction land can cause complex land use changes that affect ecosystem service values (ESV). In this study, we investigated changes in ESV in response to land use changes in Ningwu County, in eastern Loess Plateau of China. Our aim is to provide guidance for sustainable land use planning in this region. We used remote sensing to evaluate land use changes, and applied a fast, proxy-based method for evaluating ESV at three points in time:1990, 2000, and 2010. More than 89%of the total ESV in Ningwu County was attributable to woodland and grassland. The ESV in western mountain areas show the greatest increase from 1990 to 2010, but ESV decreased the most in the low-elevation northeastern area of flat terrain. These tradeoffs led to a slight net decrease (1.0%) in Ningwu County's total ESV. Although the decline in ESV was relatively low compared to the rate of economic growth, total ESV was much lower than global and national average levels at the end of the study period.

  5. A 1.5 Ma sporopollen record of paleoecologic environment evolution in the central Chinese Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    WU Fuli; FANG Xiaomin; MA Yuzhen; AN Zhisheng; LI Jijun

    2004-01-01

    A 1.5 Ma sporopollen record was obtained from a continuous loess-paleosol sequence at Chaona in the central Chinese Loess Plateau. It shows that (1) arid herbs of largely Artemisia and Chenopodiaceae and arbors of mainly Pinus, Betula and Quercus dominate loess and paleosol, respectively, reflecting cycles of cold-dry and warm-humid conditions of glaciation and interglaciation; (2) that similar vegetation pattern and cold-dry condition were found in times of unusual thick and coarse loesses L9 and L15, which have been regarded as two extremely cold and dry times as indicated by inorganic climatic proxies; and (3) that shifts of vegetations from earlier forest-steppe to open-forest and steppe and then to steppe were found at 0.95 and 0.5 Ma, implying a stepwise of drying of the Loess Plateau in the Quaternary.

  6. CENTRAL PLATEAU REMEDIATION

    Energy Technology Data Exchange (ETDEWEB)

    ROMINE, L.D.

    2006-02-01

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

  7. Characterization of the Hanford Site and environs

    Energy Technology Data Exchange (ETDEWEB)

    Cushing, C.E. (ed.)

    1991-03-01

    The US Department of Energy (DOE) proposes to site, construct, and operate a new production reactor (NPR) intended to produce materials for the US nuclear weapons program. The DOE has determined that this proposed action constitutes an action that may significantly affect the quality of the human environment; therefore, the DOE is preparing an environmental impact statement (EIS) to assess the potential impacts of the proposed action and reasonable alternatives on the human and natural environment. The NPR-EIS is being prepared in accordance with Section 102(2)(C) of the National Environmental Policy Act of 1969 (NEPA), as implemented in regulations (40 CFR 1500--1508) promulgated by the Council on Environmental Quality (CEQ). Information on the potentially affected environment at the Hanford Site and its environs was provided to ANL by PNL in various submissions during CY-1989, and some of that information was consolidated into this report, which is considered to be supporting documentation for the NPR-EIS. 93 refs., 35 figs., 46 tabs.

  8. Climate Change and Its Impact on the Eco-Environment of the Three-Rivers Headwater Region on the Tibetan Plateau, China.

    Science.gov (United States)

    Jiang, Chong; Zhang, Linbo

    2015-09-25

    This study analyzes the impact of climate change on the eco-environment of the Three-Rivers Headwater Region (TRHR), Tibetan Plateau, China. Temperature and precipitation experienced sharp increases in this region during the past 57 years. A dramatic increase in winter temperatures contributed to a rise in average annual temperatures. Moreover, annual runoff in the Lancang (LRB) and Yangtze (YARB) river basins showed an increasing trend, compared to a slight decrease in the Yellow River Basin (YRB). Runoff is predominantly influenced by rainfall, which is controlled by several monsoon systems. The water temperature in the YRB and YARB increased significantly from 1958 to 2007 (p runoff, with a maximum value observed in the 2000s.

  9. The genome and transcriptome of Trichormus sp. NMC-1: insights into adaptation to extreme environments on the Qinghai-Tibet Plateau

    Science.gov (United States)

    Qiao, Qin; Huang, Yanyan; Qi, Ji; Qu, Mingzhi; Jiang, Chen; Lin, Pengcheng; Li, Renhui; Song, Lirong; Yonezawa, Takahiro; Hasegawa, Masami; Crabbe, M. James C.; Chen, Fan; Zhang, Ticao; Zhong, Yang

    2016-01-01

    The Qinghai-Tibet Plateau (QTP) has the highest biodiversity for an extreme environment worldwide, and provides an ideal natural laboratory to study adaptive evolution. In this study, we generated a draft genome sequence of cyanobacteria Trichormus sp. NMC-1 in the QTP and performed whole transcriptome sequencing under low temperature to investigate the genetic mechanism by which T. sp. NMC-1 adapted to the specific environment. Its genome sequence was 5.9 Mb with a G+C content of 39.2% and encompassed a total of 5362 CDS. A phylogenomic tree indicated that this strain belongs to the Trichormus and Anabaena cluster. Genome comparison between T. sp. NMC-1 and six relatives showed that functionally unknown genes occupied a much higher proportion (28.12%) of the T. sp. NMC-1 genome. In addition, functions of specific, significant positively selected, expanded orthogroups, and differentially expressed genes involved in signal transduction, cell wall/membrane biogenesis, secondary metabolite biosynthesis, and energy production and conversion were analyzed to elucidate specific adaptation traits. Further analyses showed that the CheY-like genes, extracellular polysaccharide and mycosporine-like amino acids might play major roles in adaptation to harsh environments. Our findings indicate that sophisticated genetic mechanisms are involved in cyanobacterial adaptation to the extreme environment of the QTP. PMID:27381465

  10. Diets and environments of late Cenozoic mammals in the Qaidam Basin, Tibetan Plateau: Evidence from stable isotopes

    Science.gov (United States)

    Zhang, Chunfu; Wang, Yang; Li, Qiang; Wang, Xiaoming; Deng, Tao; Tseng, Zhijie J.; Takeuchi, Gary T.; Xie, Gangpu; Xu, Yingfeng

    2012-06-01

    The timing history and driving mechanisms of C4 expansion and Tibetan uplift are hotly debated issues. Paleoenvironmental evidence from within the Tibetan Plateau is essential to help resolve these issues. Here we report results of stable C and O isotope analyses of tooth enamel samples from a variety of late Cenozoic mammals, including deer, giraffe, horse, rhino, and elephant, from the Qaidam Basin in the northeastern Tibetan Plateau. The enamel-δ13C values are <-8‰ for modern samples and ≤-7‰ for fossils, except for one late Miocene rhino (CD0722, with δ13C values up to -4.1‰). If the Qaidam Basin was as arid as today in the Mio-Pliocene, these data would indicate that the majority of the animals had C3 diets and only a few individuals (besides the exceptional rhino CD0722) may have consumed some C4 plants. Based on geological evidence, however, the Qaidam Basin was probably warmer and more humid during the late Miocene and early Pliocene than today. Thus, these δ13C values likely indicate that many individuals had significant dietary intakes of C4 plants, and the Qaidam Basin had more C4 plants in the late Miocene and early Pliocene than today. Moreover, the Qaidam Basin likely had much denser vegetation at those times in order to support such large mammals as rhinos and elephants. While the δ18O values did not increase monotonously with time, the range of variation seems to have increased considerably since the early Pliocene, indicating increased aridification in the basin. The mean δ18O values of large mammals and those reconstructed for local meteoric waters display a significant negative shift in the late Miocene, consistent with the marine δ18O record which shows a cooling trend in the same period. Taken together, the isotope data suggest a warmer, wetter, and perhaps lower Qaidam Basin during the late Miocene and early Pliocene. Increased aridification after the early Pliocene is likely due to a combined effect of regional tectonism, which

  11. Characterization of the Virgo Seismic Environment

    CERN Document Server

    Accadia, T; Astone, P; Ballardin, G; Barone, F; Barsuglia, M; Basti, A; Bauer, Th S; Bebronne, M; Beker, M G; Belletoile, A; Bitossi, M; Bizouard, M A; Blom, M; Bondu, F; Bonelli, L; Bonnand, R; Boschi, V; Bosi, L; Bouhou, B; Braccini, S; Bradaschia, C; Branchesi, M; Briant, T; Brillet, A; Brisson, V; Bulik, T; Bulten, H J; Buskulic, D; Buy, C; Cagnoli, G; Calloni, E; Canuel, B; Carbognani, F; Cavalier, F; Cavalieri, R; Cella, G; Cesarini, E; Chaibi, O; Chassande-Mottin, E; Chincarini, A; Chiummo, A; Cleva, F; Coccia, E; Cohadon, P -F; Colacino, C N; Colas, J; Colla, A; Colombini, M; Conte, A; Coughlin, M; Coulon, J -P; Cuoco, E; DAntonio, S; Dattilo, V; Davier, M; Day, R; De Rosa, R; Debreczeni, G; Del Pozzo, W; del Prete, M; Di Fiore, L; Di Lieto, A; Emilio, M Di Paolo; Di Virgilio, A; Dietz, A; Drago, M; Endroczi, G; Fafone, V; Ferrante, I; Fidecaro, F; Fiori, I; Flaminio, R; Forte, L A; Fournier, J -D; Franc, J; Frasca, S; Frasconi, F; Galimberti, M; Gammaitoni, L; Garufi, F; Gaspar, M E; Gemme, G; Genin, E; Gennai, A; Giazotto, A; Gouaty, R; Granata, M; Greverie, C; Guidi, G M; Hayau, J -F; Heidmann, A; Heitmann, H; Hello, P; Jaranowski, P; Kowalska, I; Krolak, A; Leroy, N; Letendre, N; Li, T G F; Liguori, N; Lorenzini, M; Loriette, V; Losurdo, G; Majorana, E; Maksimovic, I; Man, N; Mantovani, M; Marchesoni, F; Marion, F; Marque, J; Martelli, F; Masserot, A; Michel, C; Milano, L; Minenkov, Y; Mohan, M; Morgado, N; Morgia, A; Mosca, S; Mours, B; Naticchioni, L; Nocera, F; Pagliaroli, G; Palladino, L; Palomba, C; Paoletti, F; Parisi, M; Pasqualetti, A; Passaquieti, R; Passuello, D; Persichetti, G; Piergiovanni, F; Pietka, M; Pinard, L; Poggiani, R; Prato, M; Prodi, G A; Punturo, M; Puppo, P; Rabeling, D S; Racz, I; Rapagnani, P; Re, V; Regimbau, T; Ricci, F; Robinet, F; Rocchi, A; Rolland, L; Romano, R; Rosinska, D; Ruggi, P; Sassolas, B; Sentenac, D; Sperandio, L; Sturani, R; Swinkels, B; Tacca, M; Taffarello, L; Toncelli, A; Tonelli, M; Torre, O; Tournefier, E; Travasso, F; Vajente, G; Brand, J F J van den; Broeck, C Van Den; van der Putten, S; Vasuth, M; Vavoulidis, M; Vedovato, G; Verkindt, D; Vetrano, F; Vicere, A; Vinet, J -Y; Vitale, S; Vocca, H; Ward, R L; Was, M; Yvert, M; Zadrozny, A; Zendri, J -P

    2011-01-01

    The Virgo gravitational wave detector is an interferometer (ITF) with 3km arms located in Pisa, Italy. From July to October 2010, Virgo performed its third science run (VSR3) in coincidence with the LIGO detectors. Despite several techniques adopted to isolate the interferometer from the environment, seismic noise remains an important issue for Virgo. Vibrations produced by the detector infrastructure (such as air conditioning units, water chillers/heaters, pumps) are found to affect Virgo's sensitivity, with the main coupling mechanisms being through beam jitter and scattered light processes. The Advanced Virgo (AdV) design seeks to reduce ITF couplings to environmental noise by having most vibration-sensitive components suspended and in-vacuum, as well as muffle and relocate loud machines. During the months of June and July 2010, a Guralp-3TD seismometer was stationed at various locations around the Virgo site hosting major infrastructure machines. Seismic data were examined using spectral and coherence ana...

  12. Statistical Characterization of Electromagnetic Wave Propagation in Mine Environments

    KAUST Repository

    Yucel, Abdulkadir C.

    2013-01-01

    A computational framework for statistically characterizing electromagnetic (EM) wave propagation through mine tunnels and galleries is presented. The framework combines a multi-element probabilistic collocation method with a full-wave fast Fourier transform and fast multipole method accelerated surface integral equation-based EM simulator to statistically characterize fields from wireless transmitters in complex mine environments. 1536-1225 © 2013 IEEE.

  13. Characterizing the unique photochemical environment in China

    Science.gov (United States)

    Liu, Z.; Wang, Y.; Gu, D.; Zhao, C.; Huey, L. G.; Stickel, R.; Liao, J.

    2010-12-01

    Recent observational evidence suggests that the atmospheric chemical system over China could be more complex than expected, possibly as a result of the rapid increasing anthropogenic emissions. During the CAREBeijing-2007 Experiment in August of 2007, up to 14 ppbv of peroxyacetyl nitrate (PAN, CH3C(O)OONO2) and 4.5 ppbv of glyoxal (CHOCHO) were observed, among the highest levels observed in the world in recent years. Elevated nitrous acid (HNO2) (~1.0 ppbv on average) was also observed in the early afternoon despite of the moderate amount of its precursors, i.e. nitrogen oxides (NOx=NO + NO2). We employ a 1-D photochemical model (REAM) to analyze the observations. The results indicate that reactive aromatics are the dominating source of PAN (55%-75%) and glyoxal (90%), and methylglyoxal is the major precursor of peroxy acetyl radical (50%). Downward transport from boundary layer is found to contribute ~50% of the PAN observed at surface. Photolysis of HNO2 is by far the largest primary OH source (more than 50%) throughout the daytime, and yet the fast formation rate of HNO2 inferred from the observations could not be explained by current known mechanisms. Detailed photochemical analysis is conducted to understand the controlling factors for O3 formation. O3 formation chemistry is strongly affected by aromatics and HNO2. By providing a large primary OH source, HNO2 leads to ~25% enhancement of the average O3 production rate, and aromatics contribute ~40% by serving as a major source of RO2 and HO2 radicals. Due to the large abundance of reactive hydrocarbons, O3 formation is generally NOx limited, although the sensitivity is low that a 50% reduction of NOx could only result in less than 25% reduction of the O3 production rate. Future research targeting HNO2 formation mechanism and emission sources of aromatics is necessary for better understanding the unique photochemical environment in China under significant anthropogenic impacts and the regional pollution

  14. Chemical characterization of submicron aerosol and particle growth events at a national background site (3295 m a.s.l. in the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    W. Du

    2015-05-01

    Full Text Available Atmospheric aerosols exert highly uncertain impacts on radiative forcing and also have detrimental effects on human health. While aerosol particles are widely characterized in megacities in China, aerosol composition, sources and particle growth in rural areas in the Tibetan Plateau remain less understood. Here we present the results from an autumn study that was conducted from 5 September to 15 October 2013 at a national background monitoring station (3295 m a.s.l. in the Tibetan Plateau. The submicron aerosol composition and particle number size distributions were measured in situ with an Aerodyne Aerosol Chemical Speciation Monitor (ACSM and a Scanning Mobility Particle Sizer (SMPS. The average mass concentration of submicron aerosol (PM1 is 11.9 μg m−3 (range: 1.0–78.4 μg m−3 for the entire study, which is much lower than those observed at urban and rural sites in eastern China. Organics dominated PM1 on average accounting for 43%, followed by sulfate (28% and nitrate (1%. Positive matrix factorization analysis of ACSM organic aerosol (OA mass spectra identified an oxygenated OA (OOA and a biomass burning OA (BBOA. The OOA dominated OA composition accounting for 85% on average, 17% of which was inferred from aged BBOA. The BBOA contributed a considerable fraction of OA (15% due to the burning of cow dung and straws in September. New particle formation and growth events were frequently observed (80% of time throughout the study. The average particle growth rate is 2.0 nm h−1 (range: 0.8–3.2 nm h−1. By linking the evolution of particle number size distribution to aerosol composition, we found an elevated contribution of organics during particle growth periods and also a positive relationship between the growth rate and the fraction of OOA in OA, which potentially indicates an important role of organics in particle growth in the Tibetan Plateau.

  15. Method for material characterization in a non-anechoic environment

    Science.gov (United States)

    Pometcu, L.; Sharaiha, A.; Benzerga, R.; Tamas, R. D.; Pouliguen, P.

    2016-04-01

    This paper presents a characterization method for extracting the reflection coefficient of materials and the real part of their permittivity. The characterization is performed in a real environment, as opposed to the classical measurement methods that require an anechoic chamber. In order to reduce the effects of the multipath propagation, a free space bistatic measurement was performed at different distances material-antennas in far field. By using a Teflon sample and a commercial absorbing material sample, measurements have been performed in order to validate the characterization technique.

  16. CHARACTERIZATION OF MANAGEMENT IN RESIDENTIAL AREAS WITHIN THE VENEZUELAN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    María Roselia Aira

    2016-10-01

    Full Text Available The objective of the research is to characterize the management of residential development in a Venezuelan environment. This study is documentary, supported on observation, data collection and analysis; guiding the reflection of reality. The results showed the advisability of implementing a management consider the theory of systems, contingencial view, appropriate to each particular situation management systems, and consider Latin American culture.

  17. A characterization of rice-growing environments in West Africa.

    NARCIS (Netherlands)

    Andriesse, W.; Fresco, L.O.

    1991-01-01

    Building on past classifications, this article proposes a comprehensive characterization of rice-growing environments in West Africa on the basis of ecological and agronomic parameters. Using climate, soils, toposequence, land types and rice cropping system as classificatory principles, 18 different

  18. Statistical characterization of wave propagation in mine environments

    KAUST Repository

    Bakir, Onur

    2012-07-01

    A computational framework for statistically characterizing electromagnetic (EM) wave propagation through mine tunnels and galleries is presented. The framework combines a multi-element probabilistic collocation (ME-PC) method with a novel domain-decomposition (DD) integral equation-based EM simulator to obtain statistics of electric fields due to wireless transmitters in realistic mine environments. © 2012 IEEE.

  19. Climate Change and Its Impact on the Eco-Environment of the Three-Rivers Headwater Region on the Tibetan Plateau, China

    Directory of Open Access Journals (Sweden)

    Chong Jiang

    2015-09-01

    Full Text Available This study analyzes the impact of climate change on the eco-environment of the Three-Rivers Headwater Region (TRHR, Tibetan Plateau, China. Temperature and precipitation experienced sharp increases in this region during the past 57 years. A dramatic increase in winter temperatures contributed to a rise in average annual temperatures. Moreover, annual runoff in the Lancang (LRB and Yangtze (YARB river basins showed an increasing trend, compared to a slight decrease in the Yellow River Basin (YRB. Runoff is predominantly influenced by rainfall, which is controlled by several monsoon systems. The water temperature in the YRB and YARB increased significantly from 1958 to 2007 (p < 0.001, driven by air temperature changes. Additionally, owing to warming and wetting trends in the TRHR, the net primary productivity (NPP and normalized difference vegetation index (NDVI showed significant increasing trends during the past half-century. Furthermore, although an increase in water erosion due to rainfall erosivity was observed, wind speeds declined significantly, causing a decline in wind erosion, as well as the frequency and duration of sandstorms. A clear regional warming trend caused an obvious increasing trend in glacier runoff, with a maximum value observed in the 2000s.

  20. Characterization of nano-textured samples in a production environment

    DEFF Research Database (Denmark)

    Madsen, Morten Hannibal; Hansen, Poul-Erik; Bilenberg, Brian

    2015-01-01

    Nano-textured surfaces have been characterized by optical diffraction techniques using an adapted commercial light microscope with two detectors, a CCD camera and a spectrometer. We demonstrate that the microscope has a resolution in the nanometer range, also in an environment with many vibration...... as the beam spot is kept inside an area with homogenous structures, which makes the proposed microscope well suited for implementation in a production environment.......Nano-textured surfaces have been characterized by optical diffraction techniques using an adapted commercial light microscope with two detectors, a CCD camera and a spectrometer. We demonstrate that the microscope has a resolution in the nanometer range, also in an environment with many vibrations...

  1. Organic Geochemical Characteristics and Depositional Environment of Aǧaçbaşi Plateau Peat, Köprübaşi/Trabzon, NE Turkey

    Science.gov (United States)

    Hoş Çebi, Fatma; Korkmaz, Sadettin

    2013-04-01

    Young peat deposits crop out in the southern part of the Aǧaçbaşı region of Trabzon city, Northern Turkey. In this study, chemical, organic geochemical, petrographic and palynological features of the peat occurrences are investigated and results obtained evaluated. According to palynological investigations, it is determined that peats were occured in terrestrial or lacustrine environments, which is containing average of 80% woody, 15% herbaceous and 5% amorphous organic matter. Age of peats has been determined as Miocene or younger, by the palynological age determinations. It is understood from the obtained SCI (Sport Color Index) analysis results that constituting organic material of peat is immature. Total organic carbon content of the peat is average 41.69% by pyrolysis analysis. HI values were calculated as average 315.46 mgHC/gTOC, which is very high for the coal occurrences. The high OI values (avg. 134 mgCO2/gTOC) show that the environments of peat deposits were oxic or suboxic. TAR (Terrigenous/Aquatic Ratio) and CPI (Carbon Preference Index) index value, is found to be 2.4 and 3.4 respectively. These values that resulted from dominance of high-numbered n-alkanes, indicate terrestrial organic matter input. According to the m/z 191 and m/z 217 mass peaks of GC chromatogram data which is obtained by biomarker analysis, sterane/hopane ratio suggests algal organic matter. Moreover, the lack of C34 and C35 homohopans show that organic matter deposited under oxic or suboxic conditions. Moretane/hopane, Tm/Ts and Tm/C30 hopane ratios were calculated in order of 0.15, 3.25 and 0.33, respectively. These values imply acidic and oxic conditions during the formation of peat. Due to the absence of 17α(H)-28.30-bisnorhopan in the m/z 191 chromatograms, it is concluded that Aǧaçbaşı plateau peat might be deposited in a terrestrial or lacustrine environments under oxic or suboxic conditions. Dominant sterane content of C29 suggests terrestrial organic matter input

  2. Characterization of the life cycle of the tick Haemaphysalis tibetensis under field conditions in Qinghai-Tibet plateau.

    Science.gov (United States)

    Liu, Ming; Li, Tuo; Yu, Zhi-Jun; Gao, Xiao-He; Zuo, Chun-Wei; Wang, Rong-Rong; Li, Ning-Xin; Wang, Hui; Liu, Jing-Ze

    2016-05-01

    The tick Haemaphysalis tibetensis Hoogstraal is found uniquely in the Qinghai-Tibet plateau of Tibet and Gansu of China. Not much is known of this tick. Therefore, in this study we investigated the life cycle of H. tibetensis under field conditions from March 2014 to March 2015 in Damxung County, north Lhasa City in Tibet (Autonomous Region in China). The results of the study demonstrated that the tick H. tibetensis requires an average of 177.8 days (range 129-202 days) to complete a life cycle, with rabbits supplied as hosts in the field plot. Under natural lighting and climate conditions, the feeding period of females was an average of 7.7 days, and the pre-oviposition period was 9.4 days, followed by 28.2 days for oviposition. The premolting period of nymphs lasted 52.7 days, which was the longest life cycle phase. The average weight ratio of engorged to unfed females was 58.2. Additionally, there was a highly positive correlation between the weight of engorged and the number of the eggs that were laid (r = 0.83, P < 0.05). The reproductive efficiency index and reproductive fitness index in females were 5.1 and 4.7, respectively.

  3. Reconstruction of biological drought conditions during the past 2847 years in an alpine environment of the northeastern Tibetan Plateau, China, and possible linkages to solar forcing

    Science.gov (United States)

    Yin, Zhi-Yong; Zhu, Haifeng; Huang, Lei; Shao, Xuemei

    2016-08-01

    In this study we reconstructed the moisture condition of the eastern Qaidam Basin of the northeastern Tibetan Plateau based on a 3585-year tree ring chronology. The growth environment of Qilian juniper (Sabina przewalskii Kom.) on the mountains in the eastern Qaidam Basin was first determined by comparing precipitation and temperature estimates from two spatial datasets (PRISM and World Climate). Moisture balance was calculated as the sum of simulated moisture deficit (negative) and surplus using a modified Thornthwaite water balance model, and used as a proxy of biological drought conditions. Using data during 1956-2005, we established the transfer function to reconstruct a 2847-year series of January-June moisture balance (843 BCE-2004 CE). With an adjusted R2 value of 0.654 of the transfer function and strong performance in validation, the reconstructed January-June moisture balance can be considered an excellent indicator of biological drought conditions for the study region. The reconstructed series showed strong correlations with reconstructed PDSI in the monsoon Asian region, representing a region of 10° latitudes by 20° longitudes. Using the reconstructed series, we identified centennial-scale dry periods since 843 BCE: 381-277 BCE, 425-520 CE, 1108-1212 CE, 1428-1516 CE, and 1634-1743 CE. Additionally it had statistically significant negative correlations with a monsoon intensity proxy based on oxygen stable isotope from southwestern China (Dongge Cave). Further analyses identified significant relationships with solar activity, especially during the last 700 years. We confirmed the ~ 200-year cyclic pattern in the reconstructed moisture balance series, which matched the known 210-year de Vries solar cycle and peaked during the Little Ice Age. However, the cyclic patterns of the reconstructed moisture balance series and solar activity were decoupled for the period prior to approx. 1300 CE.

  4. A GPGPU accelerated modeling environment for quantitatively characterizing karst systems

    Science.gov (United States)

    Myre, J. M.; Covington, M. D.; Luhmann, A. J.; Saar, M. O.

    2011-12-01

    The ability to derive quantitative information on the geometry of karst aquifer systems is highly desirable. Knowing the geometric makeup of a karst aquifer system enables quantitative characterization of the systems response to hydraulic events. However, the relationship between flow path geometry and karst aquifer response is not well understood. One method to improve this understanding is the use of high speed modeling environments. High speed modeling environments offer great potential in this regard as they allow researchers to improve their understanding of the modeled karst aquifer through fast quantitative characterization. To that end, we have implemented a finite difference model using General Purpose Graphics Processing Units (GPGPUs). GPGPUs are special purpose accelerators which are capable of high speed and highly parallel computation. The GPGPU architecture is a grid like structure, making it is a natural fit for structured systems like finite difference models. To characterize the highly complex nature of karst aquifer systems our modeling environment is designed to use an inverse method to conduct the parameter tuning. Using an inverse method reduces the total amount of parameter space needed to produce a set of parameters describing a system of good fit. Systems of good fit are determined with a comparison to reference storm responses. To obtain reference storm responses we have collected data from a series of data-loggers measuring water depth, temperature, and conductivity at locations along a cave stream with a known geometry in southeastern Minnesota. By comparing the modeled response to those of the reference responses the model parameters can be tuned to quantitatively characterize geometry, and thus, the response of the karst system.

  5. [Dynamic monitoring of ecological environment in loess hilly and gully region of Loess Plateau based on remote sensing: A case study on Fuxian County in Shaanxi Province. Northwest China].

    Science.gov (United States)

    Li, Fen-ling; Chang, Qin-rui; Shen, Jian; Liu, Jing

    2015-12-01

    Based on the principal component analysis (PCA), four ecological evaluation indicators including vegetation index, wet index, land surface temperature and soil index were combined to evaluate the ecological environment quality of Fuxian County in hilly and gully area of Loess Plateau from year 1995 to 2014. The results showed that the RSEI integrated RS and PCA method could reveal regional ecological changes objectively and quantitatively. The level of overall regional ecological status in Fuxian County was good with a high vegetation fraction and rich biodiversity. The synthetical ecological environment quality index increased from 3.17 to 3.53 indicating the ecological environment had been improved greatly in recent 20 years. The area with best ecological environment quality was located in Niuwu town. The magnitude of change increased progressively from northwest to southeast, and the biggest change occurred in Jiaodao and Nandaode towns. From 1995 to 2014, the areas with decreased and increased ecological environment quality were 16.7% and 42.7% of the study area, respectively, and the improved regions were mainly distributed in plateau and hilly area in the center, rocky low mountainous area in northeast and the Ziwuling Nature Reserve area in southwest of the county.

  6. A comparison of pelagic, littoral, and riverine bacterial assemblages in Lake Bangongco, Tibetan Plateau.

    Science.gov (United States)

    Liu, Yongqin; Priscu, John C; Yao, Tandong; Vick-Majors, Trista J; Michaud, Alexander B; Jiao, Nianzhi; Hou, Juzhi; Tian, Lide; Hu, Anyi; Chen, Zhong-Qiang

    2014-08-01

    Lakes of the Tibetan Plateau lack direct anthropogenic influences, providing pristine high-altitude (> 4000 m) sites to study microbial community structure. We collected samples from the pelagic, littoral, and riverine zones of Lake Bangongco, located on the western side of the Plateau, to characterize bacterial community composition and geochemistry in three distinct, but hydrologically connected aquatic environments during summer. Bacterial community composition differed significantly among zones, with communities changing from riverine zones dominated by Bacteroidetes to littoral and pelagic zones dominated by Gammaproteobacteria. Community composition was strongly related to the geochemical environment, particularly concentrations of major ions and total nitrogen. The dominance of Gammaproteobacteria in the pelagic zone contrasts with typical freshwater bacterial communities as well as other lakes on the Tibetan Plateau. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  7. DURIP: Piezoresponse Force Microscope (PFM) with Controlled Environment for Characterization of Flexoelectric Nanostructures

    Science.gov (United States)

    2015-04-21

    DURIP: Piezoresponse Force Microscope (PFM) with Controlled Environment for Characterization of Flexoelectric Nanostructures A piezo-force... microscope (PFM) system was acquired under this support for characterization of flexoelectric micro/nanostructures in a controlled environment. The system...published in non peer-reviewed journals: Final Report: DURIP: Piezoresponse Force Microscope (PFM) with Controlled Environment for Characterization of

  8. Characterization of culturable Paenibacillus spp. from the snow surface on the high Antarctic Plateau (DOME C) and their dissemination in the Concordia research station.

    Science.gov (United States)

    Van Houdt, Rob; Deghorain, Marie; Vermeersch, Marjorie; Provoost, Ann; Lo Giudice, Angelina; Leys, Natalie; Perez-Morga, David; Van Melderen, Laurence; Michaud, Luigi

    2013-07-01

    Culturable psychrotolerant bacteria were isolated from the top snow on the high Antarctic Plateau surrounding the research station Concordia. A total of 80 isolates were recovered, by enrichment cultures, from two different isolation sites (a distant pristine site [75° S 123° E] and a site near the secondary runway of Concordia). All isolates were classified to the genus Paenibacillus by 16S rRNA gene phylogenetic analysis and belonged to two different species (based on threshold of 97 % similarity in 16S rRNA gene sequence). ERIC-PCR fingerprinting indicated that the isolates from the two different sites were not all clonal. All isolates grew well from 4 to 37 °C and were resistant to ampicillin and streptomycin. In addition, the isolates from the secondary runway were resistant to chromate and sensitive to chloramphenicol, contrary to those from the pristine site. The isolates were compared to 29 Paenibacillus isolates, which were previously recovered from inside the Concordia research station. One of these inside isolates showed ERIC- and REP-PCR fingerprinting profiles identical to those of the runway isolates and was the only inside isolate that was resistant to chromate and sensitive to chloramphenicol. The latter suggested that dissemination of culturable Paenibacillus strains between the harsh Antarctic environment and the inside of the Concordia research station occurred. In addition, inducible prophages, which are potentially involved in horizontal dissemination of genes, were detected in Paenibacillus isolates recovered from outside and inside the station. The highest lysogeny was observed in strains harvested from the hostile environment outside the station.

  9. Prehistoric human settling on the Tibetan Plateau

    Science.gov (United States)

    Chen, Fahu; Zhang, Dongju; Dong, Guanghui

    2017-04-01

    When and where did human first settle down on the Tibetan Plateau is under hot debate among archaeologist, anthropologists, geneticist and paleo-geographers. Based on systematic archaeological, chronological and archaeo-botanical studies of 53 sites in Northeastern Tibetan Plateau, we propose that agriculture facilitated human permanent settlement on the Tibetan Plateau initially since 5200 years ago below 2500 masl and since 3600 years ago up to around 4000 masl, possibly assisted by domesticated animals (Chen et al. 2015). By studying hand- and footprints in Chusang, Meyer et al. (2016) argue that hunter-gatherers permanently occupied central Tibetan Plateau in early Holocene without the help of agriculture. However, we think the limited hand- and footprints evidence found in Chusang could indicate no more than prehistoric hunter-gatherers presence on the remote central Tibetan Plateau in the early Holocene. In addition, by reviewing all the published archaeological data, we propose that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in the Northeastern Tibetan Plateau (NETP). This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) when human adapted to the high altitude environment and climate change with different strategies and techniques. Particularly, the prevail of microlithic technology in North China provoked hunter-gatherers' first visit to the NETP in relatively ameliorated last Deglacial period, and the the quick development of millet farming and subsequent mixed barley-wheat farming and sheep herding facilitated farmers and herders permanently settled in Tibetan Plateau, even above 3000 masl, during mid- and late Holocene. References: Chen et al., 2015. Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 BP. Science, 347: 248-250. Meyer et al., 2016

  10. 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.

  11. First cultivation and characterization of Mycobacterium ulcerans from the environment.

    Directory of Open Access Journals (Sweden)

    Françoise Portaels

    Full Text Available BACKGROUND: Mycobacterium ulcerans disease, or Buruli ulcer (BU, is an indolent, necrotizing infection of skin, subcutaneous tissue and, occasionally, bones. It is the third most common human mycobacteriosis worldwide, after tuberculosis and leprosy. There is evidence that M. ulcerans is an environmental pathogen transmitted to humans from aquatic niches; however, well-characterized pure cultures of M. ulcerans from the environment have never been reported. Here we present details of the isolation and characterization of an M. ulcerans strain (00-1441 obtained from an aquatic Hemiptera (common name Water Strider, Gerris sp. from Benin. METHODOLOGY/PRINCIPAL FINDINGS: One culture from a homogenate of a Gerris sp. in BACTEC became positive for IS2404, an insertion sequence with more than 200 copies in M. ulcerans. A pure culture of M. ulcerans 00-1441 was obtained on Löwenstein-Jensen medium after inoculation of BACTEC culture in mouse footpads followed by two other mouse footpad passages. The phenotypic characteristics of 00-1441 were identical to those of African M. ulcerans, including production of mycolactone A/B. The nucleotide sequence of the 5' end of 16S rRNA gene of 00-1441 was 100% identical to M. ulcerans and M. marinum, and the sequence of the 3' end was identical to that of the African type except for a single nucleotide substitution at position 1317. This mutation in M. ulcerans was recently discovered in BU patients living in the same geographic area. Various genotyping methods confirmed that strain 00-1441 has a profile identical to that of the predominant African type. Strain 00-1441 produced severe progressive infection and disease in mouse footpads with involvement of bone. CONCLUSION: Strain 00-1441 represents the first genetically and phenotypically identified strain of M. ulcerans isolated in pure culture from the environment. This isolation supports the concept that the agent of BU is a human pathogen with an environmental

  12. First Cultivation and Characterization of Mycobacterium ulcerans from the Environment

    Science.gov (United States)

    Portaels, Françoise; Meyers, Wayne M.; Ablordey, Anthony; Castro, António G.; Chemlal, Karim; de Rijk, Pim; Elsen, Pierre; Fissette, Krista; Fraga, Alexandra G.; Lee, Richard; Mahrous, Engy; Small, Pamela L. C.; Stragier, Pieter; Torrado, Egídio; Van Aerde, Anita; Silva, Manuel T.; Pedrosa, Jorge

    2008-01-01

    Background Mycobacterium ulcerans disease, or Buruli ulcer (BU), is an indolent, necrotizing infection of skin, subcutaneous tissue and, occasionally, bones. It is the third most common human mycobacteriosis worldwide, after tuberculosis and leprosy. There is evidence that M. ulcerans is an environmental pathogen transmitted to humans from aquatic niches; however, well-characterized pure cultures of M. ulcerans from the environment have never been reported. Here we present details of the isolation and characterization of an M. ulcerans strain (00-1441) obtained from an aquatic Hemiptera (common name Water Strider, Gerris sp.) from Benin. Methodology/Principal Findings One culture from a homogenate of a Gerris sp. in BACTEC became positive for IS2404, an insertion sequence with more than 200 copies in M. ulcerans. A pure culture of M. ulcerans 00-1441 was obtained on Löwenstein-Jensen medium after inoculation of BACTEC culture in mouse footpads followed by two other mouse footpad passages. The phenotypic characteristics of 00-1441 were identical to those of African M. ulcerans, including production of mycolactone A/B. The nucleotide sequence of the 5′ end of 16S rRNA gene of 00-1441 was 100% identical to M. ulcerans and M. marinum, and the sequence of the 3′ end was identical to that of the African type except for a single nucleotide substitution at position 1317. This mutation in M. ulcerans was recently discovered in BU patients living in the same geographic area. Various genotyping methods confirmed that strain 00-1441 has a profile identical to that of the predominant African type. Strain 00-1441 produced severe progressive infection and disease in mouse footpads with involvement of bone. Conclusion Strain 00-1441 represents the first genetically and phenotypically identified strain of M. ulcerans isolated in pure culture from the environment. This isolation supports the concept that the agent of BU is a human pathogen with an environmental niche. PMID

  13. Characterization of Polarizing Splitter Optics in Extreme Environments

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, Ryand; Olson, Matthew; Morelli, Gregg

    2013-01-04

    Development of laser systems capable of surviving extreme conditions experienced in military applications requires mounts and components that are able to survive these conditions. The characterization of mounted and/or bonded optical assemblies in harsh environments is critical for the development of laser and optical systems for functionality in these extreme conditions. Customized mounts, bonding assemblies and packaging strategies are utilized to develop and field reliable and robust optical subassemblies. Thin film polarizers operating at 45o and polarizing beam splitter cubes were chosen for initial testing based on past experiences, advancements in optical coating and construction technologies and material properties. Shock, vibration, shear strength, tensile strength and temperature testing are performed on mounted polarizing beam splitter cubes and thin film polarizers from two manufacturers. Previous testing showed that polarizing beam splitter cubes constructed using epoxy would become damaged in the laser resonator. The cubes being tested in this report are constructed using epoxy- free direct optical contact bonding. Thin film polarizers operating at 45o are chosen opposed to Brewster’s angle thin film polarizers to reduce the size and simplify design and construction since an optical wedge is not required. The components and mounts are each environmentally tested beyond the manufacturers’ specifications for shock, vibration, and temperature. Component functionality is monitored during and after the environmental testing. Experimental results from the testing will be discussed as will the impact on future laser resonator designs.

  14. Carbon fiber composite characterization in adverse thermal environments.

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Vasquez, Sylvia; Brown, Alexander L.; Hubbard, Joshua A.; Ramirez, Ciro J.; Dodd, Amanda B.

    2011-05-01

    The behavior of carbon fiber aircraft composites was studied in adverse thermal environments. The effects of resin composition and fiber orientation were measured in two test configurations: 102 by 127 millimeter (mm) test coupons were irradiated at approximately 22.5 kW/m{sup 2} to measure thermal response, and 102 by 254 mm test coupons were irradiated at approximately 30.7 kW/m{sup 2} to characterize piloted flame spread in the vertically upward direction. Carbon-fiber composite materials with epoxy and bismaleimide resins, and uni-directional and woven fiber orientations, were tested. Bismaleimide samples produced less smoke, and were more resistant to flame spread, as expected for high temperature thermoset resins with characteristically lower heat release rates. All materials lost approximately 20-25% of their mass regardless of resin type, fiber orientation, or test configuration. Woven fiber composites displayed localized smoke jetting whereas uni-directional composites developed cracks parallel to the fibers from which smoke and flames emanated. Swelling and delamination were observed with volumetric expansion on the order of 100% to 200%. The purpose of this work was to provide validation data for SNL's foundational thermal and combustion modeling capabilities.

  15. Holocene moisture and East Asian summer monsoon evolution in the northeastern Tibetan Plateau recorded by Lake Qinghai and its environs: A review of conflicting proxies

    Science.gov (United States)

    Chen, Fahu; Wu, Duo; Chen, Jianhui; Zhou, Aifeng; Yu, Junqing; Shen, Ji; Wang, Sumin; Huang, Xiaozhong

    2016-12-01

    Climatic and environmental changes in the northeastern Tibetan Plateau are controlled by the Asian summer monsoon (ASM) and the westerlies, two key circulation components of the global climate system which directly affect a large human population and associated ecosystems in eastern Asia. During the past few decades, a series of Holocene palaeoclimatic records have been obtained from sediment cores from Lake Qinghai and from various other geological archives in the surrounding area of the northeastern Tibetan Plateau. However, because of uncertainties regarding the sediment chronologies and the climatic significance of the proxies used, the nature of Holocene climatic changes in the region remains unclear and even controversial. Here we review all major classes of the published data from drilled cores from Lake Qinghai, as well as other evidence from lakes and aeolian deposits from surrounding areas, in order to reconstruct changes in moisture patterns and possible summer monsoon evolution in the area during the Holocene. Combining the results of moisture and precipitation proxies such as vegetation history, pollen-based precipitation reconstruction, aeolian activity, lake water depth/lake level changes, salinity and sediment redness, we conclude that moisture and precipitation began to increase in the early Holocene, reached their maximum during the middle Holocene, and decreased during the late Holocene - similar to the pattern of the East Asian summer monsoon (EASM) in northern China. It is clear that the region experienced a relatively dry climate and weak EASM during the early Holocene, as indicated by relatively low tree pollen percentages and fluctuating pollen concentrations; generally low lake levels of Lake Qinghai and the adjacent Lake Hurleg and Lake Toson in the Qaidam Basin; and widely distributed aeolian sand deposition in the Lake Qinghai Basin and the nearby Gonghe Basin to the south, and in the eastern Qaidam Basin to the west. We argue that the

  16. Stability of alpine meadow ecosystem on the Qinghai- Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    ZHOU Huakun; ZHOU Li; ZHAO Xinquan; LIU Wei; LI Yingnian; GU Song; ZHOU Xinmin

    2006-01-01

    The meadow ecosystem on the Qinghai-Tibetan Plateau is considered to be sensitive to climate change. An understanding of the alpine meadow ecosystem is therefore important for predicting the response of ecosystems to climate change. In this study, we use the coefficients of variation (Cv) and stability (E) obtained from the Haibei Alpine Meadow Ecosystem Research Station to characterize the ecosystem stability. The results suggest that the net primary production of the alpine meadow ecosystem was more stable (Cv = 13.18%) than annual precipitation (Cv = 16.55%) and annual mean air temperature (Cv = 28.82%). The net primary production was insensitive to either the precipitation (E = 0.0782) or air temperature (E = 0.1113). In summary, the alpine meadow ecosystem on the Qinghai- Tibetan Plateau is much stable. Comparison of alpine meadow ecosystem stability with other five natural grassland ecosystems in Israel and southern African indicates that the alpine meadow ecosystem on the Qinghai-Tibetan Plateau is the most stable ecosystem. The alpine meadow ecosystem with relatively simple structure has high stability, which indicates that community stability is not only correlated with biodiversity and community complicity but also with environmental stability. An average oscillation cycles of 3―4 years existed in annual precipitation, annual mean air temperature, net primary production and the population size of consumers at the Haibei natural ecosystem. The high stability of the alpine meadow ecosystem may be resulting also from the adaptation of the ecosystem to the alpine environment.

  17. Tibial Plateau Fractures

    DEFF Research Database (Denmark)

    Elsøe, Rasmus

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

  18. Optical Turbulence above the Internal Antarctic Plateau

    CERN Document Server

    Masciadri, E; Hagelin, S; Moigne, P Le; Noilhan, J

    2010-01-01

    The internal antarctic plateau revealed in the last years to be a site with interesting potentialities for the astronomical applications due to the extreme dryness and low temperatures, the typical high altitude of the plateau, the weak level of turbulence in the free atmosphere down to a just few tens of meters from the ground and the thin optical turbulence layer developed at the ground. The main goal of a site testing assessment above the internal antarctic plateau is to characterize the site (optical turbulence and classical meteorological parameters) and to quantify which is the gain we might obtain with respect to equivalent astronomical observations done above mid-latitude sites to support plans for future astronomical facilities. Our group is involved, since a few years, in studies related to the assessment of this site for astronomical applications that include the characterization of the meteorological parameters and optical turbulence provided by general circulation models as well as mesoscale atmo...

  19. The Pajarito Plateau: a bibliography

    Science.gov (United States)

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

    1993-01-01

    Pajarito Plateau is described as the high tableland that lies between the Jemez Mountains on the west and the Rio Grande on the east. From north to south, it extends from the Chama Valley to La Cañada de Cochiti (Hewett 1906:14)(Figure 1). Because human activity rarely stops at such definite boundaries, major ethnographic studies of Tewa (San Ildefonso and Santa Clara) and Keres (Cochiti) linguistic groups are included. (Even though most of the historic pueblos occupied by the Tewa and Keres are not located on the Pajarito Plateau, oral traditions and archaeological data suggest that these groups once occupied sites on the plateau.) Towa studies are not included because Steen believed Towa ancestors were not involved in major cultural developments of the Pajarito Plateau. In addition, a bibliography of the Jemez area (home of Towa people) has been prepared by Michael Elliott (1982) and included with his nomination of large Pueblo sites near Jemez Springs to the National Register of Historic Places that is on file at the Museum of New Mexico, Laboratory of Anthropology, in Santa Fe. Both Steen and Mathien included references to geographically and historically related material that does not focus on the Pajarito Plateau but, nonetheless, is important to understanding the area's archaeology and physical environment, for example, lithic resources available from Cerro Pedernal or in the Sangre de Cristo Mountains.

  20. 40 CFR 81.162 - Northeast Plateau Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

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

  1. Radar Characterization of the Interplanetary Meteoroid Environment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a new modeling effort that will make substantial refinements and improvements to our existing models of the interplanetary meteoroid environment near...

  2. Major problems and control measures of water ecological environment in Inner MongoliaXinjiang Plateau%中国蒙新高原湖区水环境主要问题及控制对策

    Institute of Scientific and Technical Information of China (English)

    张亚丽; 许秋瑾; 席北斗; 张列宇

    2011-01-01

    The policy ' The development campaign of the western regions' has great significance for balancing the developing disparities between different regions and improving the economic strength of China. The fragile ecological environment of the western regions determines that ecological protection should be set as the basic point, and that economic development should be combined with sustainable development in those regions. This paper systematically formulates major problems and control measures of aquatic ecosystems in Inner Mongolia-Xinjiang Plateau, where is under the influence of climate change and human activities. We choose Lake Wuliangsuhai, Lake Hulun, Lake Bosten, Lake Chaiwopu and Lake Ebinnr as typical examples and analyze the changes in water ecological status in the recent decades. It is confirmed that the degradation of water ecological environment occurs. This paper aims at understanding the current characteristics of lakes in Inner Mongolia-Xinjiang Plateau and providing theoretical support for reasonable development of lake resources and protection of water ecological environment. At present, lakes in Inner Mongolia-Xinjiang Plateau is arid and semi-arid and there exists many problems, such as lake size shrinking, salinization, sediment, deterioration of water quality and structural changes of aquatic ecosystem. Compared with lakes in east China, the research on the Inner Mongolia-Xinjiang Plateau in our country lacks of systematic knowledge and lagging relatively, although some basic research and information have been developed. In the future, the following fields will be focused on: (1) the evolution and trend of water environmental quality in the Inner Mongolia-Xinjiang Plateau under the influence of climate change; (2) the effect of water allocation on regional hydrodynamic conditions, pollutant transport process and the influence of water scheduling to important environmental fac-tots; (3) selecting characteristic physical and chemical factors of

  3. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments.

    Directory of Open Access Journals (Sweden)

    Erin E Conners

    Full Text Available Increasingly, 'place', including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC, whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1 Participatory mapping; 2 Quantitative interviews; 3 Sex work venue field observation; 4 Time-location-activity diaries; 5 In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions.

  4. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments

    Science.gov (United States)

    Conners, Erin E.; West, Brooke S.; Roth, Alexis M.; Meckel-Parker, Kristen G.; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D.; Brouwer, Kimberly C.

    2016-01-01

    Increasingly, ‘place’, including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  5. Radiative plateau inflation

    CERN Document Server

    Ballesteros, Guillermo

    2016-01-01

    We describe how monomial chaotic inflation becomes compatible with the latest CMB data thanks to radiative corrections producing a plateau. The interactions of the inflation with other fields, required for reheating, can flatten the potential and moderate the production of primordial gravitational waves, keeping these below the current upper bound. We show that the appearance of a plateau requires that the inflaton couples to fermions and to another scalar or a gauge group. We give concrete examples of minimal particle physics models leading to plateaus for quadratic and quartic chaotic inflation. We also provide a three-parameter model-independent description of radiatively corrected inflation that is amenable to CMB analyses.

  6. Elastic wave scattering to characterize heterogeneities in the borehole environment

    Science.gov (United States)

    Tang, Xiao-Ming; Li, Zhen; Hei, Chuang; Su, Yuan-Da

    2016-04-01

    Scattering due to small-scale heterogeneities in the rock formation surrounding a wellbore can significantly change the acoustic waveform from a logging measurement which in turn can be used to characterize the formation heterogeneities. This study simulates the elastic heterogeneity scattering in monopole and dipole acoustic logging and analyse the resulting effects on the waveforms. The results show that significant coda waves are generated in both monopole and dipole waveforms and the dipole coda is dominated by S-to-S scattering, which can be effectively utilized to diagnose the heterogeneity in the rock formation. The coda wave modelling and analysis were used to characterize dipole acoustic data logged before and after fracturing a reservoir interval, with significant coda wave in the after-fracturing data indicating fracturing-induced heterogeneous property change in the rock volume surrounding the borehole.

  7. Mineral characterization of soil type ranker formed on serpentines occurring in southern Belgrade environs Bubanj Potok

    National Research Council Canada - National Science Library

    Cekić Božidar Đ; Ivanovski Valentin N; Đorđević Aleksandar; Aleksić Velimir; Tomić Zorica; Bogdanović Stefan; Umićević Ana B

    2012-01-01

    ... located in the southern Belgrade environs, Serbia. Characterization of the ranker soil was conducted by scanning electron microscopy, X-ray diffraction, micro-Raman spectroscopy and transmission 57Fe...

  8. 南极考察队员在不同高原环境下血氧饱和度及心率与高原反应风险的关系%Study of blood oxygen saturation, heart rate changes and plateau reaction of the Antarctic Kunlun station investigation team in different plateau environments

    Institute of Scientific and Technical Information of China (English)

    赵顺云; 吴新民; 郭亚民; 张树顺; 安艳明; 李冰; 王皓

    2013-01-01

    目的 探讨南极考察队员在不同高原环境下血氧饱和度、心率变化与高原反应风险的关系.方法 2010年8月至2011年4月采用无创性氧饱和度测定仪监测(MD300-C) 16名南极考察队员在不同海拔情况以及不同高原环境(西藏高原和南极高原)下的血氧饱和度和心率变化以及高原反应情况,根据Lake Louise Consensus急性高原反应症状评分和判定方法,判定急性高原反应的程度.结果 16名考察队员在我国海拔110、3650、4300 m时血氧饱和度、心率情况差异均有统计学意义[96.8%±1.2%、89.1%±1.2%、86.1%±2.0%,(75.0±5.4)次/min、(104.0±4.3)次/min、(113.0±5.2)次/min,F=214.155、240.088,均P<0.05].南极高原环境下不同海拔(2000、2500、3000、3500、4087 m)血氧饱和度、心率差异也均有统计学意义[91.9%±1.3%、90.5%±1.3%、87.6%±1.4%、85.0%±1.8%、81.5%±2.2%,(85.9±3.2)次/min、(90.6±2.8)次/min、(97.8±4.1)次/min、(102.0±3.4)次/min、(106.3±3.9)次/min,F=105.418、90.174,均P<0.05].在南极高原环境下氧饱和度、心率与Lake Louise Consensus急性高原病症状评分相关(r=-0.446、0.565,均P<0.05).结论 南极考察队员在西藏高原和南极高原不同海拔下血氧饱和度、心率有明显的变化,且随着海拔的升高,高原反应风险逐渐增加.%Objective To explore the blood oxygen saturation and heart rate changes of the Antarctic expeditioners.Methods During August 2010 to April 2011,the changes in blood oxygen saturation,heart rate and plateau reaction of 16 Antarctic expedition team in different plateau environments (Tibetan plateau versus Antarctic plateau) were monitored with the noninvasive pulse oximeter MD300-C.The extent of acute mountain sickness was determined according to the Lake Louise Consensus acute mountain reaction symptom scores and judgment method.Results The changes of blood oxygen saturation,heart rate at different altitudes

  9. Stable isotope variations (δ18O and δD) in modern waters across the Andean Plateau

    Science.gov (United States)

    Bershaw, John; Saylor, Joel E.; Garzione, Carmala N.; Leier, Andrew; Sundell, Kurt E.

    2016-12-01

    Environmental parameters that influence the isotopic composition of meteoric water (δ18O and δD) are well characterized up the windward side of mountains, where orographic precipitation results in a predictable relationship between the isotopic composition of precipitation and elevation. The topographic and climatic evolution of the Andean Plateau and surrounding regions has been studied extensively by exploiting this relationship through the use of paleowater proxies. However, interpretation on the plateau itself is challenged by a poor understanding of processes that fractionate isotopes during vapor transport and rainout, and by the relative contribution of unique moisture sources. Here, we present an extensive dataset of modern surface water samples for the northern Andean Plateau and surrounding regions to elucidate patterns and causes of isotope fractionation in this continental environment. These data show a progressive increase in δ18O of stream water west of the Eastern Cordillera (∼1‰/70 km), almost identical to the rate observed across the Tibetan Plateau, attributed to a larger fraction of recycled water in precipitation and/or increased evaporative enrichment downwind. This may lead to underestimates of paleoelevation, particularly for sites deep into the rainshadow of the Eastern Cordilleran crest. That said, elevation is a primary control on the isotopic composition of surface waters across the entire Andean Plateau and its flanks when considering the most negative δ18O values, highlighting the need for sufficiently large datasets to distinguish minimally evaporated samples. There is a general increase in δ18O on the plateau from north to south, concomitant with an increase in aridity and decrease in convective moistening (amount effect). Lastly, stable isotope and seasonal precipitation patterns suggest easterlies provide the vast majority of moisture that falls as precipitation across the Andean Plateau and Western Cordillera, from Peru to

  10. Characterization factors for thermal pollution in freshwater aquatic environments.

    Science.gov (United States)

    Verones, Francesca; Hanafiah, Marlia Mohd; Pfister, Stephan; Huijbregts, Mark A J; Pelletier, Gregory J; Koehler, Annette

    2010-12-15

    To date the impact of thermal emissions has not been addressed in life cycle assessment despite the narrow thermal tolerance of most aquatic species. A method to derive characterization factors for the impact of cooling water discharges on aquatic ecosystems was developed which uses space and time explicit integration of fate and effects of water temperature changes. The fate factor is calculated with a 1-dimensional steady-state model and reflects the residence time of heat emissions in the river. The effect factor specifies the loss of species diversity per unit of temperature increase and is based on a species sensitivity distribution of temperature tolerance intervals for various aquatic species. As an example, time explicit characterization factors were calculated for the cooling water discharge of a nuclear power plant in Switzerland, quantifying the impact on aquatic ecosystems of the rivers Aare and Rhine. The relative importance of the impact of these cooling water discharges was compared with other impacts in life cycle assessment. We found that thermal emissions are relevant for aquatic ecosystems compared to other stressors, such as chemicals and nutrients. For the case of nuclear electricity investigated, thermal emissions contribute between 3% and over 90% to Ecosystem Quality damage.

  11. Plateau Indian Ways with Words

    Science.gov (United States)

    Monroe, Barbara

    2009-01-01

    The indigenous rhetoric of the Plateau Indians continues to exert a discursive influence on student writing in reservation schools today. Plateau students score low on state-mandated tests and on college writing assignments, in large part because the pervasive personalization of Plateau rhetoric runs counter to the depersonalization of academic…

  12. Greening the Plateau

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Located on the world’s largest plateau, Tibet Autonomous Region in China’s southwest has an average elevation of 4,000 meters. Tibet’s diverse natural landscapes, including snow-capped mountains, vast pastures and virgin forests, combined with its

  13. Characterization of coaxial rocket injector sprays under high pressure environments

    Science.gov (United States)

    Sankar, S. V.; Wang, G.; Brena De La Rosa, A.; Rudoff, R. C.; Isakovic, A.; Bachalo, W. D.

    1992-01-01

    The effect of elevated environment pressures on the atomization characteristics of a single element, scaled-down, shear-coaxial rocket injector has been investigated. In this study, the shear coaxial injector was operated with water and air as simulants for conventionally used liquid oxygen and hydrogen gas, respectively. The experiments were conducted in a specially designed high pressure rig. A two-component PDPA/DSA system was used to study the spray characteristics at different chamber pressures ranging from atmospheric to 100 psig. The study showed an overall increase in the droplet sizes at higher chamber pressures. This phenomenon is attributed to a decrease in the secondary atomization effects at higher chamber pressures which, in turn, is directly related to a decrease in the shear experienced by the droplets as they move axially through the pressure chamber.

  14. Re-Configurable Electronics Characterization under Extreme Thermal Environment

    Science.gov (United States)

    Stoica, Adrian; Lacayo, Veronica; Ramesham, Rajeshuni; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher

    2005-01-01

    The need for reconfigurable electronics is driven by requirements to survive longer missions and harsher environments. It is possible to compensate for degradations in Extreme Environments (EE). EE has effect on electronics: circuits are designed to exploit device characteristics and when a certain temperature or radiation range is exceeded the circuit function gradually degrades. It is possible to employ Hardening by reconfiguration (HBR) to mitigate drifts, degradation, or damage on electronic devices in EE by using reconfigurable devices and an adaptive self-reconfiguration of circuit topology. In this manner degraded components can be salvaged, and completely damaged components can be bypassed. The challenge of conventional design is replaced with that of designing a recover process that automatically performs the (re) design in place of the designer. The objective of testing a Digital Signal Processor (DSP) under the extreme temperatures was to determine the lowest temperature at which the DAP can operate. The objective of testing a Xilinx VirtexII Pro FPGA board was to initially find our whether the evaluation board and the FPGA would survive and continue at temperature ranges from -180 C, and 120 C. The Virtex II functioned correctly at the temperatures tested. The next test was done on the GM-C filter building block using the same temperature range as the Virtex II. The current lower and upper limits were shown to be reduced as the temperature gets lower. The device function can be recovered by increasing the Vb from .08V to .85V. The negative and positive saturation voltages increases as the temperature gets higher. The function of the device can be recovered by decreasing the Vb from .8V to around .75V. The next test was performed to test the recovery of the GmC low pass filter through Vb in a filter circuit. The test indicate that bias voltage control adjustment is an efficient mechanism for circuit recovery at extreme temperatures.

  15. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Castro, V.A.; Ott, C.M.; Garcia, V.M.; John, J.; Buttner, M.P.; Cruz, P.; Pierson, D.L.

    2009-01-01

    The determination of risk from infectious disease during long-duration missions is composed of several factors including the concentration and the characteristics of the infectious agent. Thus, a thorough knowledge of the microorganisms aboard spacecraft is essential in mitigating infectious disease risk to the crew. While stringent steps are taken to minimize the transfer of potential pathogens to spacecraft, several medically significant organisms have been isolated from both the Mir and International Space Station (ISS). Historically, the method for isolation and identification of microorganisms from spacecraft environmental samples depended upon their growth on culture media. Unfortunately, only a fraction of the organisms may grow on a culture medium, potentially omitting those microorganisms whose nutritional and physical requirements for growth are not met. Thus, several pathogens may not have been detected, such as Legionella pneumophila, the etiological agent of Legionnaire s disease. We hypothesize that environmental analysis using non-culture-based technologies will reveal microorganisms, allergens, and microbial toxins not previously reported in spacecraft, allowing for a more complete health assessment. The development of techniques for this flight experiment, operationally named SWAB, has already provided advances in NASA laboratory processes and beneficial information toward human health risk assessment. The translation of 16S ribosomal DNA sequencing for the identification of bacteria from the SWAB experiment to nominal operations has increased bacterial speciation of environmental isolates from previous flights three fold compared to previous conventional methodology. The incorporation of molecular-based DNA fingerprinting using repetitive sequence-based polymerase chain reaction (rep-PCR) into the capabilities of the laboratory has provided a methodology to track microorganisms between crewmembers and their environment. Both 16S ribosomal DNA

  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. Tectonomagmatic Associations on the Central Andean Plateau

    Science.gov (United States)

    de Silva, S. L.; Viramonte, J. G.

    2012-12-01

    The Neogene evolution of the Central Andes is characterized by a strong association between plate convergence, mountain building and plateau formation, and magmatism. Plateau uplift by crustal shortening and thickening in the lower crust is broadly coincident with large scale silicic magmatism defined by the Neogene Central Andean ignimbrite province. Of particular interest here are the spatiotemporal correlations between silicic magmatism and tectonic evolution of the Altiplano-Puna plateau. Although magmatism is driven by the subduction-related flux from mantle to crust, the shift to "crustal" magmatism as indicated by elevated crustal isotopic indices after ~10Ma suggests a link between crustal thickening, plateau formation and silicic magmatism. In particular, elevated geotherms associated with crustal thickening and enhanced mantle flux associated with lithospheric delamination may have played a role in thermally preparing the Central Andean crust for enhanced silicic magma production during the extensive Neogene ignimbrite flare-up. Emplacement of these magmas in the upper crust throughout the Neogene may have fuelled a period of significant interaction between magmatism and tectonism on the plateau. With particular reference to the 21° to 24°S segment of the Central Andes, spatial and structural coincidence of calderas of the Altiplano Puna Volcanic Complex with the NW-SE striking Calama-Olacapata-El Toro fault zone suggests significant tectonomagmatic interaction. Location of calderas suggest that these regional faults focused magma intrusion and storage, while spatially and temporally correlated eruption pulses connote a tectonic control. Indeed, current thermomechanical models of magma chamber development and eruption triggering promote a role for external triggering of "perched" upper crustal magma chambers. This might have been achieved by melt-enhanced deformation, or alternatively, significant uplift (~1km) associated with the development of large

  18. Plateau Waves of Intracranial Pressure and Multimodal Brain Monitoring.

    Science.gov (United States)

    Dias, Celeste; Maia, Isabel; Cerejo, Antonio; Smielewski, Peter; Paiva, José-Artur; Czosnyka, Marek

    2016-01-01

    The aim of this study was to describe multimodal brain monitoring characteristics during plateau waves of intracranial pressure (ICP) in patients with head injury, using ICM+ software for continuous recording. Plateau waves consist of an abrupt elevation of ICP above 40 mmHg for 5-20 min. This is a prospective observational study of patients with head injury who were admitted to a neurocritical care unit and who developed plateau waves. We analyzed 59 plateau waves that occurred in 8 of 18 patients (44 %). At the top of plateau waves arterial blood pressure remained almost constant, but cerebral perfusion pressure, cerebral blood flow, brain tissue oxygenation, and cerebral oximetry decreased. After plateau waves, patients with a previously better autoregulation status developed hyperemia, demonstrated by an increase in cerebral blood flow and brain oxygenation. Pressure and oxygen cerebrovascular reactivity indexes (pressure reactivity index and ORxshort) increased significantly during the plateau wave as a sign of disruption of autoregulation. Bedside multimodal brain monitoring is important to characterize increases in ICP and give differential diagnoses of plateau waves, as management of this phenomenon differs from that of regular ICP.

  19. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Ott, C. M.; John, J.; Castro, V. A.; Cruz, P.; Buttner, L. M.; Pierson, D. L.

    2007-01-01

    polymerase chain reaction (rep-PCR). This technology has allowed contamination tracking of microorganisms between crewmembers and their environment. This study not only demonstrated that ISS has a greater diversity of organisms than originally expected, but also provided insight into possible routes of infection to the crew. Additional ground-based studies used rep-PCR and protein based assays to determine the potential of methicillin resistant Staphylococcus aureus (MRSA) aboard ISS. MRSA has become increasingly common on Earth and pose a treatment problem for infections during flight. While no MRSA have been isolated from ISS to date, the mecA gene product that is responsible for methicillin resistance was isolated in other Staphylococcus species aboard ISS suggesting a potential of MRSA through gene transfer. Using improved sample collection technologies, flight sampling for SWAB was initiated in August 2006 and should continue through spring of 2007. The focus of these flight samples is the collection of DNA for evaluation by Denaturing Gradient Gel Electrophoresis (DGGE). Unlike other techniques, DGGE does not depend on any microbial growth on culture media allowing a more comprehensive assessment of the spacecraft interior. This study should provide insight into the true microbial ecology that is experienced by the crew during flight. This information will lead toward an accurate microbial risk assessment to help set flight requirements to protect the safety, health, and performance of the crew.

  20. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Ott, C. M.; John, J.; Castro, V. A.; Cruz, P.; Buttner, L. M.; Pierson, D. L.

    2007-01-01

    polymerase chain reaction (rep-PCR). This technology has allowed contamination tracking of microorganisms between crewmembers and their environment. This study not only demonstrated that ISS has a greater diversity of organisms than originally expected, but also provided insight into possible routes of infection to the crew. Additional ground-based studies used rep-PCR and protein based assays to determine the potential of methicillin resistant Staphylococcus aureus (MRSA) aboard ISS. MRSA has become increasingly common on Earth and pose a treatment problem for infections during flight. While no MRSA have been isolated from ISS to date, the mecA gene product that is responsible for methicillin resistance was isolated in other Staphylococcus species aboard ISS suggesting a potential of MRSA through gene transfer. Using improved sample collection technologies, flight sampling for SWAB was initiated in August 2006 and should continue through spring of 2007. The focus of these flight samples is the collection of DNA for evaluation by Denaturing Gradient Gel Electrophoresis (DGGE). Unlike other techniques, DGGE does not depend on any microbial growth on culture media allowing a more comprehensive assessment of the spacecraft interior. This study should provide insight into the true microbial ecology that is experienced by the crew during flight. This information will lead toward an accurate microbial risk assessment to help set flight requirements to protect the safety, health, and performance of the crew.

  1. Characterizing CO2 fluxes for growing and non-growing seasons in a shrub ecosystem on the Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    XU; Shixiao; ZHAO; Xinquan; FU; Yuling; ZHAO; Liang; LI; Yi

    2005-01-01

    To assess carbon budget for shrub ecosystems on the Qinghai-Tibet Plateau, CO2flux was measured with an open-path eddy covariance system for an alpine shrub ecosystem during growing and non-growing seasons. CO2 flux dynamics was distinct between the two seasons. During the growing season from May to September, the ecosystem exhibited net CO2uptake from 08:00 to 19:00 (Beijing Standard Time), but net CO2 emission from 19:00 to 08:00.Maximum CO2 uptake appeared around 12:00 with values of 0.71, 1.19, 1.46 and 0.67 g CO2m-2 h-1 for June, July, August and September, respectively. Diurnal fluctuation of CO2 flux showed higher correlation with photosynthetic photon flux density than temperature. The maximum net CO2 influx occurred in August with a value of 247 g CO2 m-2. The total CO2 uptake by the ecosystem was up to 583 g CO2 m-2 for the growing season. During the non-growing season from January to April and from October to December, CO2 flux showed small fluctuation with the largest net CO2 efflux of 0.30 g CO2 m-2 h-1 in April. The diurnal CO2 flux was close to zero during most time of the day, but showed a small net CO2 efflux from 11:00 to 18:00. Diurnal CO2 flux, is significantly correlated to diurnal temperature in the non-growing season. The maximum monthly net CO2 efflux appeared in April, with a value of 105 g CO2 m-2. The total net CO2 efflux for the whole non-growing season was 356 g CO2 m-2.

  2. Assessment of Technologies Used to Characterize Wildlife Populations in the Offshore Environment

    Energy Technology Data Exchange (ETDEWEB)

    Duberstein, Corey A.; Tagestad, Jerry D.; Larson, Kyle B.

    2011-12-09

    Wind energy development in the offshore environment can have both direct and indirect effects on wildlife, yet little is known about most species that use near-shore and offshore waters due in part to the difficulty involved in studying animals in remote, challenging environments. Traditional methods to characterize offshore wildlife populations include shipboard observations. Technological advances have provided researches with an array of technologies to gather information about fauna from afar. This report describes the use and application of radar, thermal and optical imagery, and acoustic detection technologies for monitoring birds, bats, and marine mammals in offshore environments.

  3. Neutron Environment Characterization of the Central Cavity in the Annular Core Research Reactor *

    Directory of Open Access Journals (Sweden)

    Parma Edward J.

    2016-01-01

    Full Text Available Characterization of the neutron environment in the central cavity of the Sandia National Laboratories' Annular Core Research Reactor (ACRR is important in order to provide experimenters with the most accurate spectral information and maintain a high degree of fidelity in performing reactor experiments. Characterization includes both modeling and experimental efforts. Building accurate neutronic models of the ACRR and the central cavity “bucket” environments that can be used by experimenters is important in planning and designing experiments, as well as assessing the experimental results and quantifying uncertainties. Neutron fluence characterizations of two bucket environments, LB44 and PLG, are presented. These two environments are used frequently and represent two extremes in the neutron spectrum. The LB44 bucket is designed to remove the thermal component of the neutron spectrum and significantly attenuate the gamma-ray fluence. The PLG bucket is designed to enhance the thermal component of the neutron spectrum and attenuate the gamma-ray fluence. The neutron characterization for each bucket was performed by irradiating 20 different activation foil types, some of which were cadmium covered, resulting in 37 different reactions at the peak axial flux location in each bucket. The dosimetry results were used in the LSL-M2 spectrum adjustment code with a 640-energy group MCNP-generated trial spectrum, self-shielding correction factors, the SNLRML or IRDFF dosimetry cross-section library, trial spectrum uncertainty, and trial covariance matrix, to generate a least-squares adjusted neutron spectrum, spectrum uncertainty, and covariance matrix. Both environment character-izations are well documented and the environments are available for use by experimenters.

  4. Neutron Environment Characterization of the Central Cavity in the Annular Core Research Reactor

    Science.gov (United States)

    Parma, Edward J.; Naranjo, Gerald E.; Lippert, Lance L.; Vehar, David W.

    2016-02-01

    Characterization of the neutron environment in the central cavity of the Sandia National Laboratories' Annular Core Research Reactor (ACRR) is important in order to provide experimenters with the most accurate spectral information and maintain a high degree of fidelity in performing reactor experiments. Characterization includes both modeling and experimental efforts. Building accurate neutronic models of the ACRR and the central cavity "bucket" environments that can be used by experimenters is important in planning and designing experiments, as well as assessing the experimental results and quantifying uncertainties. Neutron fluence characterizations of two bucket environments, LB44 and PLG, are presented. These two environments are used frequently and represent two extremes in the neutron spectrum. The LB44 bucket is designed to remove the thermal component of the neutron spectrum and significantly attenuate the gamma-ray fluence. The PLG bucket is designed to enhance the thermal component of the neutron spectrum and attenuate the gamma-ray fluence. The neutron characterization for each bucket was performed by irradiating 20 different activation foil types, some of which were cadmium covered, resulting in 37 different reactions at the peak axial flux location in each bucket. The dosimetry results were used in the LSL-M2 spectrum adjustment code with a 640-energy group MCNP-generated trial spectrum, self-shielding correction factors, the SNLRML or IRDFF dosimetry cross-section library, trial spectrum uncertainty, and trial covariance matrix, to generate a least-squares adjusted neutron spectrum, spectrum uncertainty, and covariance matrix. Both environment character-izations are well documented and the environments are available for use by experimenters. Work supported by the United States Department of Energy at Sandia National Laboratories. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned

  5. Isolation, identification and characterization of Bacillus cereus from the dairy environment.

    NARCIS (Netherlands)

    te Giffel, M.C.

    1997-01-01

    In this thesis the occurrence of Bacillus cereus in the milk production and processing environment was investigated. Isolates were identified biochemically and by DNA probes based on the variable regions of 16S rRNA. Further characterization was carried out using biochemical and molecular typing, in

  6. Isolation, identification and characterization of Bacillus cereus from the dairy environment

    NARCIS (Netherlands)

    Giffel, te M.

    1997-01-01

    In this thesis the occurrence of Bacillus cereus in the milk production and processing environment was investigated. Isolates were identified biochemically and by DNA probes based on the variable regions of 16S rRNA. Further characterization was carried out using bioche

  7. Isolation, identification and characterization of Bacillus cereus from the dairy environment

    NARCIS (Netherlands)

    Giffel, te M.

    1997-01-01

    In this thesis the occurrence of Bacillus cereus in the milk production and processing environment was investigated. Isolates were identified biochemically and by DNA probes based on the variable regions of 16S rRNA. Further characterization was carried out using

  8. Dendrochronological potential of the alpine shrub Rhododendron nivale on the south-eastern Tibetan Plateau.

    Science.gov (United States)

    Liang, Eryuan; Eckstein, Dieter

    2009-09-01

    Shrubs and dwarf shrubs are wider spread on the Tibetan Plateau than trees and hence offer a unique opportunity to expand the present dendrochronological network into extreme environments beyond the survival limit of trees. Alpine shrublands on the Tibetan Plateau are characterized by rhododendron species. The dendrochronological potential of one alpine rhododendron species and its growth response to the extreme environment on the south-east Tibetan Plateau were investigated. Twenty stem discs of the alpine snowy rhododendron (Rhododendron nivale) were collected close to the tongue of the Zuoqiupu Glacier in south-east Tibet, China. The skeleton plot technique was used for inter-comparison between samples to detect the growth pattern of each stem section. The ring-width chronology was developed by fitting a negative exponential function or a straight line of any slope. Bootstrapping correlations were calculated between the standard chronology and monthly climate data. The wood of snowy rhododendron is diffuse-porous with evenly distributed small-diameter vessels. It has well-defined growth rings. Most stem sections can be visually and statistically cross-dated. The resulting 75-year-long standard ring-width chronology is highly correlated with a timberline fir chronology about 200 km apart, providing a high degree of confidence in the cross-dating. The climate/growth association of alpine snowy rhododendron and of this timberline fir is similar, reflecting an impact of monthly mean minimum temperatures in November of the previous year and in July during the year of ring formation. The alpine snowy rhododendron offers new research directions to investigate the environmental history of the Tibetan Plateau in those regions where up to now there was no chance of applying dendrochronology.

  9. Earth-Facing Antenna Characterization in a Complex Ground Plane/Multipath Rich Environment

    Science.gov (United States)

    Welch, Bryan W.; Piasecki, Marie T.

    2015-01-01

    The Space Communications and Navigation (SCAN) Testbed was a Software Defined Radio (SDR)-based payload launched to the International Space Station (ISS) in July of 2012. The purpose of the SCAN Testbed payload was to investigate the applicability of SDRs to NASA space missions in an operational space environment, which means that a proper model for system performance in said operational space environment is a necessary condition. The SCAN Testbed has line-of-sight connections to various ground stations with its S-Band Earth-facing Near-Earth Network Low Gain Antenna (NEN-LGA). Any previous efforts to characterize the NEN-LGA proved difficult, therefore, the NASA Glenn Research Center built its own S-Band ground station, which became operational in 2015, and has been successfully used to characterize the NEN-LGAs in-situ pattern measurements. This methodology allows for a more realistic characterization of the antenna performance, where the pattern oscillation induced by the complex ISS ground plane, as well as shadowing effects due to ISS structural blockage are included into the final performance model. This paper describes the challenges of characterizing an antenna pattern in this environment. It will also discuss the data processing, present the final antenna pattern measurements and derived model, as well as discuss various lessons learned.

  10. Earth-Facing Antenna Characterization in Complex Ground Plane/Multipath Rich Environment

    Science.gov (United States)

    Welch, Bryan W.; Piasecki, Marie T.

    2015-01-01

    The Space Communications and Navigation (SCAN) Testbed was a Software Defined Radio (SDR)-based payload launched to the International Space Station (ISS) in July of 2012. The purpose of the SCAN Testbed payload was to investigate the applicability of SDRs to NASA space missions in an operational environment, which means that a proper model for system performance in said operational space environment is a necessary condition. The SCAN Testbed has line-of-sight connections to various ground stations with its S-Band Earth-facing Near-Earth-Network Low Gain Antenna (NEN-LGA). Any previous efforts to characterize the NEN-LGA proved difficult, therefore, the NASA Glenn Research Center built its own S-Band ground station, which became operational in 2015, and has been used successfully to characterize the NEN-LGA's in-situ pattern measurements. This methodology allows for a more realistic characterization of the antenna performance, where the pattern oscillation induced by the complex ISS ground plane, as well as shadowing effects due to ISS structural blockage are included into the final performance model. This paper describes the challenges of characterizing an antenna pattern in this environment. It will also discuss the data processing, present the final antenna pattern measurements and derived model, as well as discuss various lessons learned

  11. Characterization of natural co-cultures of Piromyces with Methanobrevibacter ruminantium from yaks grazing on the Qinghai-Tibetan Plateau: a microbial consortium with high potential in plant biomass degradation.

    Science.gov (United States)

    Wei, Ya-Qin; Yang, Hong-Jian; Long, Rui-Jun; Wang, Zhi-Ye; Cao, Bin-Bin; Ren, Qin-Chang; Wu, Tian-Tian

    2017-12-01

    Anaerobic fungi reside in the gut of herbivore and synergize with associated methanogenic archaea to decompose ingested plant biomass. Despite their potential for use in bioconversion industry, only a few natural fungus-methanogen co-cultures have been isolated and characterized. In this study we identified three co-cultures of Piromyces with Methanobrevibacter ruminantium from the rumen of yaks grazing on the Qinghai Tibetan Plateau. The representative co-culture, namely (Piromyces + M. ruminantium) Yak-G18, showed remarkable polysaccharide hydrolase production, especially xylanase. Consequently, it was able to degrade various lignocellulose substrates with a biodegrading capability superior to most previously identified fungus or fungus-methanogen co-culture isolates. End-product profiling analysis validated the beneficial metabolic impact of associated methanogen on fungus as revealed by high-yield production of methane and acetate and sustained growth on lignocellulose. Together, our data demonstrated a great potential of (Piromyces + M. ruminantium) Yak-G18 co-culture for use in industrial bioconversion of lignocellulosic biomass.

  12. Hydrogeology of the Markagunt Plateau, Southwestern Utah

    Science.gov (United States)

    Spangler, Lawrence E.

    2010-01-01

    The Markagunt Plateau, in southwestern Utah, lies at an altitude of about 9,500 feet and is capped primarily by Quaternary-age basalt that overlies Eocene-age freshwater limestone of the Claron Formation. Over large parts of the Markagunt Plateau, dissolution of the Claron limestone and subsequent collapse of the overlying basalt have produced a terrain characterized by sinkholes as much as 1,000 feet across and 100 feet deep. Numerous large springs discharge from the basalt and underlying limestone on the plateau, including Mammoth Spring, one of the largest springs in Utah, with a discharge that can exceed 300 cubic feet per second. Discharge from Mammoth Spring is from the Claron Formation; however, recharge to the spring largely takes place by both focused and diffuse infiltration through the basalt that caps the limestone. Results of dye tracing to Mammoth Spring indicate that recharge originates largely southwest of the spring outside of the Mammoth Creek watershed, as well as from losing reaches along Mammoth Creek. Maximum groundwater travel time to the spring from dye-tracer tests during the snowmelt runoff period was about 1 week. Specific conductance and water temperature data from the spring show an inverse relation to discharge during snowmelt runoff and rainfall events, also indicating short groundwater residence times. Results of major-ion analyses for samples collected from Mammoth and other springs on the plateau indicate calcium-bicarbonate type water containing low (less than 200 mg/L) dissolved-solids concentrations. Investigations in the Navajo Lake area along the southern margin of the plateau have shown that water losing to sinkholes bifurcates and discharges to both Cascade and Duck Creek Springs, which subsequently flow into the Virgin and Sevier River basins, respectively. Groundwater travel times to these springs, on the basis of dye tracing, were about 8.5 and 53 hours, respectively. Similarly, groundwater travel time from Duck Creek

  13. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  14. Characterization of oxides of stainless steel UNS S30400 formed in offshore environment

    Energy Technology Data Exchange (ETDEWEB)

    Cindra Fonseca, M. [Universidade Federal Fluminense, PGMEC - Programa de Pos-Graduacao em Engenharia Mecanica, Rua Passo da Patria, 156, Bl. D, Sala 302, 24210-240 Niteroi-RJ (Brazil); Bastos, I.N. [Instituto Politecnico/UERJ, Rua Alberto Rangel s/n, 28630-050 Nova Friburgo-RJ (Brazil); Baggio-Saitovitch, E., E-mail: esaitovitch@yahoo.com.br [Centro Brasileiro de Pesquisas Fisicas, Rua Xavier Sigaud, 150, 22290-180 Rio de Janeiro-RJ (Brazil); Sanchez, D.R. [Instituto de Fisica, Universidade Federal Fluminense, Campus da Praia Vermelha, 24210-346 Niteroi-RJ (Brazil)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Thick corrosion products of stainless steel were characterized by Moessbauer spectroscopy. Black-Right-Pointing-Pointer High content of akaganeite on the surface exposed to marine environment. Black-Right-Pointing-Pointer Nanoparticles of akaganeite were always observed. - Abstract: Thick corrosion products of austenitic stainless steel obtained from a steam turbine structure exposed in offshore environment were studied by optical stereomicroscopy, X-ray diffraction, Moessbauer and energy-dispersive X-ray spectroscopy. The external surface of mechanical structure was exposed to a marine atmosphere and the internal one to a combustion gas for two decades. Characterization of corrosion products showed high content of akaganeite in the outer region and a mixture of akaganeite and hematite in the inner surface. Besides these characteristics, a distribution of nanosized superparamagnetic particles of akaganeite was found in the rusts.

  15. Initial Characterization of the Microgravity Environment of the International Space Station: Increments 2 Through 5

    Science.gov (United States)

    Jules, K.; McPherson, K.; Hrovat, K.; Kelly, E.

    2002-01-01

    The primary objective of the International Space Station (ISS) is to provide a long-term reduced gravity environment for the conduct of scientific research for a variety of microgravity science disciplines. With the completion of flight of STS-100 (ISS flight 6A), the Microgravity Environment Program at the NASA Glenn Research Center delivered two acceleration measurement systems to the International Space Station. These acceleration measurement systems provide a generic service to microgravity payloads by measuring the quasi-steady and the vibratory acceleration environments on board the station. The Microgravity Acceleration Measurement System measures accelerations in the quasi-steady regime, including the contributions of aerodynamic drag, vehicle rotation, and vehicle venting effects. The Space Acceleration Measurement System-II measures on-board disturbances in the vibratory regime resulting from vehicle systems, crew activity, and experiment hardware. This paper presents to the microgravity scientific community the results of the initial characterization of the microgravity environment of the International Space Station for increments 2 through 4. Also, the role of the Principal Investigator Microgravity Services (PIMS) project is described in terms of ISS acceleration data distribution, processing, achieving, analyzing and characterization of the ISS as well as its interaction with the principal investigator teams. The results discussed in this paper covered both the quasi-steady and the vibratory acceleration environment of the station during its first year of operation. The ISS quasi-steady microgravity environment is described for increments 2 through 4. Results are presented and discussed for the following: Torque Equilibrium Attitude (TEA) and the X Axis Perpendicular to the Orbital Plane (XPOP) ISS attitudes; ISS docking attitudes and their effect on the quasi-steady acceleration environment as well as the impact of STS joint operation with ISS on the

  16. CENTRAL PLATEAU REMEDIATION OPTIMIZATION STUDY

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-09-19

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

  17. Climatology of monsoon precipitation over the Tibetan Plateau from 13-year TRMM observations

    Science.gov (United States)

    Aijuan, Bai; Guoping, Li

    2016-10-01

    Based on the 13-year data from the Tropical Rainfall Measuring Mission (TRMM) satellite during 2001-2013, the influencing geographical location of the Tibetan Plateau (Plateau) monsoon is determined. It is found that the domain of the Plateau monsoon is bounded by the latitude between 27° N and 37° N and the longitude between 60° E and 103° E. According to the annual relative precipitation, the Plateau monsoon can be divided into three sections: the Plateau winter monsoon (PWM) over Iran and Afghanistan, the Plateau summer monsoon (PSM) over the central Plateau, and the transiting zone of the Plateau monsoon (TPM) over the south, west, and east edges of the Plateau. In PWM and PSM, the monsoon climatology has a shorter rainy season with the mean annual rainfall of less than 800 mm. In TPM, it has a longer rainy season with the mean annual rainfall of more than 1800 mm. PWM experiences a single-peak monthly rainfall with the peak during January to March; PSM usually undergoes a multi-peak pattern with peaks in the warm season; TPM presents a double-peak pattern, with a strong peak in late spring to early summer and a secondary peak in autumn. The Plateau monsoon also characterizes an asymmetrical seasonal advance of the rain belt. In the east of the Plateau, the rain belt migrates in a south-north orientation under the impact of the tropical and subtropical systems' oscillation. In the west of the Plateau, the rain belt advances in an east-west direction, which is mainly controlled by the regional Plateau monsoon.

  18. Posterior bicondylar tibial plateau fractures.

    Science.gov (United States)

    Carlson, DuWayne A

    2005-02-01

    To present a case series of patients with posterior bicondylar tibial plateau fractures treated by direct fracture exposure and fixation through dual incisions. Retrospective clinical study. Level 1 trauma centers. Eight patients were identified that had posterior bicondylar tibial plateau fractures. Two patients had depressed posterolateral tibial plateau fractures with contained defects and did not have direct fracture exposure. One patient died of medical problems leaving 5 patients who underwent direct fracture exposure, reduction, and fixation. Posteromedial followed by posterolateral open reduction and internal fixation of posterior bicondylar tibial plateau fractures. At 6 to 24 months follow-up (mean 13 months), all patients returned to near full activities, each with aching after prolonged standing (8-hour shift). Range of motion averaged 2 degrees to 121 degrees of flexion. Three of 5 returned to manual labor jobs; the others were not employed at the time of injury. Posterior bicondylar tibial plateau fractures have a high association with lateral meniscal pathology and can be associated with anterior cruciate ligament injury. Reduction of the posterior plateau condyles is easiest with the knee in full extension. Flexion contractures can be a problem, and patients should be encouraged to regain/maintain knee extension. The dual-incision approach to these challenging fractures can result in good to excellent knee function for these patients.

  19. Characterizing the Preturbulence Environment for Sensor Development, New Hazard Algorithms and NASA Experimental Flight Planning

    Science.gov (United States)

    Kaplan, Michael L.; Lin, Yuh-Lang

    2004-01-01

    During the grant period, several tasks were performed in support of the NASA Turbulence Prediction and Warning Systems (TPAWS) program. The primary focus of the research was on characterizing the preturbulence environment by developing predictive tools and simulating atmospheric conditions that preceded severe turbulence. The goal of the research being to provide both dynamical understanding of conditions that preceded turbulence as well as providing predictive tools in support of operational NASA B-757 turbulence research flights. The advancements in characterizing the preturbulence environment will be applied by NASA to sensor development for predicting turbulence onboard commercial aircraft. Numerical simulations with atmospheric models as well as multi-scale observational analyses provided insights into the environment organizing turbulence in a total of forty-eight specific case studies of severe accident producing turbulence on commercial aircraft. These accidents exclusively affected commercial aircraft. A paradigm was developed which diagnosed specific atmospheric circulation systems from the synoptic scale down to the meso-y scale that preceded turbulence in both clear air and in proximity to convection. The emphasis was primarily on convective turbulence as that is what the TPAWS program is most focused on in terms of developing improved sensors for turbulence warning and avoidance. However, the dynamical paradigm also has applicability to clear air and mountain turbulence. This dynamical sequence of events was then employed to formulate and test new hazard prediction indices that were first tested in research simulation studies and then ultimately were further tested in support of the NASA B-757 turbulence research flights. The new hazard characterization algorithms were utilized in a Real Time Turbulence Model (RTTM) that was operationally employed to support the NASA B-757 turbulence research flights. Improvements in the RTTM were implemented in an

  20. Characterizing Microbe-Environment Interactions Through Experimental Evolution: The Autonomous Adaptive Directed Evolution Chamber

    Science.gov (United States)

    Ibanez, C. R.; Blaich, J.; Owyang, S.; Storrs, A.; Moffet, A.; Wong, N.; Zhou, J.; Gentry, D.

    2015-12-01

    We are developing a laboratory system for studying micro- to meso-scale interactions between microorganisms and their physicochemical environments. The Autonomous Adaptive Directed Evolution Chamber (AADEC) cultures microorganisms in controlled,small-scale geochemical environments. It observes corresponding microbial interactions to these environments and has the ability to adjust thermal, chemical, and other parameters in real time in response to these interactions. In addition to the sensed data, the system allows the generation of time-resolved ecological, genomic, etc. samples on the order of microbial generations. The AADEC currently houses cultures in liquid media and controls UVC radiation, heat exposure, and nutrient supply. In a proof-of-concept experimental evolution application, it can increase UVC radiation resistance of Escherichia coli cultures by iteratively exposing them to UVC and allowing the surviving cells to regrow. A baseline characterization generated a million fold resistance increase. This demonstration uses a single-well growth chamber prototype, but it was limited by scalability. We have expanded upon this system by implementing a microwell plate compatible fluidics system and sensor housing. This microwell plate system increases the diversity of microbial interactions seen in response to the geochemical environments generated by the system, allowing greater control over individual cultures' environments and detection of rarer events. The custom microfluidic card matches the footprint of a standard microwell plate. This card enables controllable fluid flow between wells and introduces multiple separate exposure and sensor chambers, increasing the variety of sensors compatible with the system. This gives the device control over scale and the interconnectedness of environments within the system. The increased controllability of the multiwell system provides a platform for implementing machine learning algorithms that will autonomously

  1. Application of terahertz spectroscopy for characterization of biologically active organic molecules in natural environment

    Science.gov (United States)

    Karaliūnas, Mindaugas; Jakštas, Vytautas; Nasser, Kinan E.; Venckevičius, Rimvydas; Urbanowicz, Andrzej; Kašalynas, Irmantas; Valušis, Gintaras

    2016-09-01

    In this work, a comparative research of biologically active organic molecules in its natural environment using the terahertz (THz) time domain spectroscopy (TDS) and Fourier transform spectroscopy (FTS) systems is carried out. Absorption coefficient and refractive index of Nicotiana tabacum L. leaves containing nicotine, Cannabis sativa L. leaves containing tetrahydrocannabinol, and Humulu lupulus L. leaves containing α-acids, active organic molecules that obtain in natural environment, were measured in broad frequency range from 0.1 to 13 THz at room temperature. In the spectra of absorption coefficient the features were found to be unique for N. tabacum, C. sativa and H. lupulus. Moreover, those features can be exploited for identification of C. sativa sex and N. tabacum origin. The refractive index can be also used to characterize different species.

  2. Eocene Tibetan Plateau remnants preserved in the Northwest Himalaya

    Science.gov (United States)

    van der Beek, P. A.; van Melle, J.; Guillot, S.; Pêcher, A.; Reiners, P. W.; Nicolescu, S.; Latif, M.

    2009-04-01

    The northwest Himalaya shows strongly contrasting relief, opposing deeply incised mountain ranges characterized by extremely rapid exhumation and some of the highest peaks in the world (i.e., the Karakorum range and Nanga Parbat massif) to high-elevation, low-relief areas such as the 4000-m high Deosai plateau in northern Pakistan and the 5000-m high Tso Morari in Indian Ladakh. The origin and evolution of such plateau regions in the syntaxis of the most active continental collision in the world remain elusive. Here, we report the first low-temperature thermochronology (apatite fission-track, apatite and zircon (U-Th)/He) data from the Deosai plateau and use thermal history modelling to show that it has undergone continuous slow (≤ 200 m/Myr) denudation and has thus remained tectonically stable for the last 35 Myr at least. The inferred history of constant slow denudation of the plateau contradicts the hypothesis that widespread low-relief surfaces in the northwest Himalaya result from efficient, km-scale glacial erosion during Quaternary times; such erosion would have been recorded as a phase of rapid recent denudation that is not observed in the data. Slow continuous denudation since Eocene times, i.e. only 15-20 Myr after the onset of India-Asia collision implies that the Deosai plateau surface developed early in the Himalayan history and limits the phase of orogenic relief growth in the Ladakh-Kohistan arc to the early Paleogene. Although thermochronology data do not directly record surface uplift, the simplest explanation for the inferred constant denudation rates is that the plateau had reached its present-day elevation already during the Eocene, as a later phase of surface uplift would have triggered an erosional response that would have been recorded by the thermochronology data. We use morphological analyses to characterise such plateaux and identify them at the scale of the entire northwest Himalaya and compare our thermochronological data with

  3. Channel characterization in high-speed railway station environments at 1.89 GHz

    Science.gov (United States)

    Zhou, Tao; Tao, Cheng; Salous, Sana; Liu, Liu; Tan, Zhenhui

    2015-11-01

    Channel characterization is the prerequisite condition for the research and development of the next-generation high-speed railway (HSR) communication system. Train station is one of typical HSR scenarios, where channel characteristics have not yet been investigated sufficiently. In this paper, wideband multiantenna channel measurements are performed at 1.89 GHz in an open-type train station environment based on long-term evolution networks along Beijing to Tianjin HSR in China. Large-scale characteristics of the HSR station channel, focusing on path loss, shadow fading (SF), and the autocorrelation property of SF, are studied. Moreover, small-scale characteristics, such as Ricean K-factor, delay spread, and spatial correlation, are analyzed and modeled. In addition, the stationary region is characterized using the RUN test method. The obtained results provide useful information for deployment and assessment of the future HSR communication system in the HSR station scenario.

  4. An experiment towards characterizing seahorse sound in a laboratory controlled environment

    Digital Repository Service at National Institute of Oceanography (India)

    Saran, A; Sreepada, R.A; Chakraborty, B.; Fernandes, W.A; Srivastava, R.; Kuncolienker, D.S.; Gawde, G.

    N a t i o n a l C o n f e r e n c e o n E l e c t r o n i c T e c h n o l o g i e s 1 5 t h & 1 6 t h A p r i l 2 K 1 1 | 138 An Experiment towards Characterizing Seahorse Sound in a Laboratory Controlled Environment Arvind K. Saran1, R.... A. Sreepada1, Bishwajit Chakraborty1, William Fernandes1, Ratan Srivastava1 1National Institute of Oceanography, Dona Paula, Goa, India Dinanath Sinai Kuncolienker 2 , Gajanan Gawde2 2Goa Engineering College, Farmagudi Ponda, Goa, India...

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

    Directory of Open Access Journals (Sweden)

    Katerina D Oikonomou

    2014-09-01

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

  6. Seismic wave speed structure of the Ontong Java Plateau

    Science.gov (United States)

    Covellone, Brian M.; Savage, Brian; Shen, Yang

    2015-06-01

    The Ontong Java Plateau (OJP) represents the result of a significant event in the Earth's geologic history. Limited geophysical and geochemical data, as well as the plateau's relative isolation in the Pacific ocean, have made interpretation of the modern day geologic structure and its 120 Ma formation history difficult. Here we present the highest resolution image to date of the wave speed structure of the OJP region. We use a data set that combines Rayleigh waves extracted from both ambient noise and earthquake waveforms and an iterative finite-frequency tomography methodology. The combination of datasets allow us to best exploit the limited station distribution in the Pacific and image wave speed structures between 35 km and 300 km into the Earth. We image a region of fast shear wave speeds, greater than 4.75 km/s, that extends to greater than 100 km beneath the plateau. The wave speeds are similar to as observed in cratonic environments and are consistent with a compositional anomaly that resulted from the residuum of eclogite entrainment during the plateau's formation. The combination of our imaged wave speed structure and previous geochemical work suggest that a surfacing plume head entrained eclogite from the deep mantle and accounts for the anomalous buoyancy characteristics of the plateau and observed fast wave speeds.

  7. Verçenik Plateau Alternative Tourism and Recreational Activities

    Directory of Open Access Journals (Sweden)

    İzzet İSLAMOĞLU

    2014-08-01

    Full Text Available In the last century working life become easier and result of this increased people free time, after that interest of tourism activities wide spread all over. Plateau tourism or highland places are not first choices of the tourism activities but plateau rec reation will give an application for potential activity place. Turkey have unmatched nature and rich environmental resources will able to give any kind of tourism activities. In that context city of Rize took place in Black Sea region with different capabi lities, one of the source areas that make up tourism and recreational activities. This research intended for Vercenik Plateau take place 60 km away from Camlihemsin district center and will determine potential tourism and recreational application. Research is based on field observation and studies. This information obtained as a result ofthis evaluationbeing associated toliterature data and that information determined which exercise can be done in the field. Vercenik Plateau; with pristine environment and ru ral locations, the fresh water supplies, unique flora for city of Rize has high recreational capacities.As a result of study; Vercenik Plateau has natural features with the great potential of the alternative tourism as it is suitable for areas but not asse ss enough potential tourism and recreational activities without prior review has been observed.

  8. Characterizing the Fish Passage Environment at The Dalles Dam Spillway: 2001-2004

    Energy Technology Data Exchange (ETDEWEB)

    Richmond, Marshall C.; Carlson, Thomas J.; Serkowski, John A.; Cook, Chris B.; Duncan, Joanne P.; Perkins, William A.

    2007-10-10

    The spill environment at The Dalles Dam in 2001-2004 was characterized using a field-deployed autonomous sensor (the so-called Sensor Fish), computational fluid dynamics (CFD) modeling, and Lagrangian particle tracking. The sensor fish has a self-contained capability to digitally the record pressure and triaxial accelerations it was exposed to following its release into the spillway. After recovery downstream of the tailrace, the data stored in the memory of the sensor are downloaded and stored for analysis. The spillway, stilling basin, and tailrace hydrodynamics were simulated using an unsteady, free-surface, three-dimensional CFD code that solved the Reynolds-averaged Navier-Stokes equations in conjunction with a two-equation turbulence model. The results from the CFD simulations were then used in a Lagrangian particle tracking model that included the effects of mass, drag, and buoyancy in the particle equation of motion. A random walk method was used to simulate the effects of small-scale turbulence on the particle motion. Several operational and structural conditions were evaluated using the Sensor Fish, CFD, and particle tracking. Quantifying events such as strike and stilling basin retention time characterized exposure conditions in the spill environment.

  9. Measuring the food environment: a systematic technique for characterizing food stores using display counts.

    Science.gov (United States)

    Miller, Cassandra; Bodor, J Nicholas; Rose, Donald

    2012-01-01

    Marketing research has documented the influence of in-store characteristics-such as the number and placement of display stands-on consumer purchases of a product. However, little information exists on this topic for key foods of interest to those studying the influence of environmental changes on dietary behavior. This study demonstrates a method for characterizing the food environment by measuring the number of separate displays of fruits, vegetables, and energy-dense snack foods (including chips, candies, and sodas) and their proximity to cash registers in different store types. Observations in New Orleans stores (N = 172) in 2007 and 2008 revealed significantly more displays of energy-dense snacks than of fruits and vegetables within all store types, especially supermarkets. Moreover, supermarkets had an average of 20 displays of energy-dense snacks within 1 meter of their cash registers, yet none of them had even a single display of fruits or vegetables near their cash registers. Measures of the number of separate display stands of key foods and their proximity to a cash register can be used by researchers to better characterize food stores and by policymakers to address improvements to the food environment.

  10. Measuring the Food Environment: A Systematic Technique for Characterizing Food Stores Using Display Counts

    Directory of Open Access Journals (Sweden)

    Cassandra Miller

    2012-01-01

    Full Text Available Marketing research has documented the influence of in-store characteristics—such as the number and placement of display stands—on consumer purchases of a product. However, little information exists on this topic for key foods of interest to those studying the influence of environmental changes on dietary behavior. This study demonstrates a method for characterizing the food environment by measuring the number of separate displays of fruits, vegetables, and energy-dense snack foods (including chips, candies, and sodas and their proximity to cash registers in different store types. Observations in New Orleans stores (N=172 in 2007 and 2008 revealed significantly more displays of energy-dense snacks than of fruits and vegetables within all store types, especially supermarkets. Moreover, supermarkets had an average of 20 displays of energy-dense snacks within 1 meter of their cash registers, yet none of them had even a single display of fruits or vegetables near their cash registers. Measures of the number of separate display stands of key foods and their proximity to a cash register can be used by researchers to better characterize food stores and by policymakers to address improvements to the food environment.

  11. BEAM: A computational workflow system for managing and modeling material characterization data in HPC environments

    Energy Technology Data Exchange (ETDEWEB)

    Lingerfelt, Eric J [ORNL; Endeve, Eirik [ORNL; Ovchinnikov, Oleg S [ORNL; Borreguero Calvo, Jose M [ORNL; Park, Byung H [ORNL; Archibald, Richard K [ORNL; Symons, Christopher T [ORNL; Kalinin, Sergei V [ORNL; Messer, Bronson [ORNL; Shankar, Mallikarjun [ORNL; Jesse, Stephen [ORNL

    2016-01-01

    Improvements in scientific instrumentation allow imaging at mesoscopic to atomic length scales, many spectroscopic modes, and now with the rise of multimodal acquisition systems and the associated processing capability the era of multidimensional, informationally dense data sets has arrived. Technical issues in these combinatorial scientific fields are exacerbated by computational challenges best summarized as a necessity for drastic improvement in the capability to transfer, store, and analyze large volumes of data. The Bellerophon Environment for Analysis of Materials (BEAM) platform provides material scientists the capability to directly leverage the integrated computational and analytical power of High Performance Computing (HPC) to perform scalable data analysis and simulation via an intuitive, cross-platform client user interface. This framework delivers authenticated, push-button execution of complex user workflows that deploy data analysis algorithms and computational simulations utilizing the converged compute-and-data infrastructure at Oak Ridge National Laboratory s (ORNL) Compute and Data Environment for Science (CADES) and HPC environments like Titan at the Oak Ridge Leadership Computing Facility (OLCF). In this work we address the underlying HPC needs for characterization in the material science community, elaborate how BEAM s design and infrastructure tackle those needs, and present a small sub-set of user cases where scientists utilized BEAM across a broad range of analytical techniques and analysis modes.

  12. Optical and Chemical Characterization of Polyimide in a GEO-like Environment

    Science.gov (United States)

    Engelhart, D.; Plis, E.; Ferguson, D.; Cooper, R.; Hoffmann, R.

    2016-09-01

    Ground- and space-based optical observations of space objects rely on knowledge about how spacecraft materials interact with light. However, this is not a static property. Each material's optical fingerprint changes continuously throughout a spacecraft's orbital lifetime. These changes in optical signature occur because energetic particles break bonds within a material and new bonds subsequently form. The newly formed bonds can be identical to the original bonds or different, resulting in a new material. The chemical bonds comprising the material dictate which wavelengths of light are absorbed. Understanding the processes of material damage and recovery individually will allow development of a predictive model for materials' optical properties as a function of exposure to the space environment. In order to characterize the properties, we have exposed samples of polyimide to high energy electrons comparable to those found in a geostationary earth orbit in order to simulate damage on orbit. The resultant changes in the material's optical fingerprint were then characterized in the wavelength range of 0.2 to 25 microns. The chemical modifications to the material that result in these optical changes have also been identified. After initial electron-induced damage, the rate and mechanism of material recovery have been monitored and found to be extremely sensitive to the exposure of the damaged material to air. The implications of that fact and experimental progress toward complete in vacuo characterization will be discussed.

  13. Characterizing the Chemical Stability of High Temperature Materials for Application in Extreme Environments

    Science.gov (United States)

    Opila, Elizabeth

    2005-01-01

    The chemical stability of high temperature materials must be known for use in the extreme environments of combustion applications. The characterization techniques available at NASA Glenn Research Center vary from fundamental thermodynamic property determination to material durability testing in actual engine environments. In this paper some of the unique techniques and facilities available at NASA Glenn will be reviewed. Multiple cell Knudsen effusion mass spectrometry is used to determine thermodynamic data by sampling gas species formed by reaction or equilibration in a Knudsen cell held in a vacuum. The transpiration technique can also be used to determine thermodynamic data of volatile species but at atmospheric pressures. Thermodynamic data in the Si-O-H(g) system were determined with this technique. Free Jet Sampling Mass Spectrometry can be used to study gas-solid interactions at a pressure of one atmosphere. Volatile Si(OH)4(g) was identified by this mass spectrometry technique. A High Pressure Burner Rig is used to expose high temperature materials in hydrocarbon-fueled combustion environments. Silicon carbide (SiC) volatility rates were measured in the burner rig as a function of total pressure, gas velocity and temperature. Finally, the Research Combustion Lab Rocket Test Cell is used to expose high temperature materials in hydrogen/oxygen rocket engine environments to assess material durability. SiC recession due to rocket engine exposures was measured as a function of oxidant/fuel ratio, temperature, and total pressure. The emphasis of the discussion for all techniques will be placed on experimental factors that must be controlled for accurate acquisition of results and reliable prediction of high temperature material chemical stability.

  14. Sandy Desertification Status and its Driving Mechanism in North Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    DONG Yuxiang

    2004-01-01

    As the main body of Qinghai-Tibetan Plateau, North Tibet Plateau is one of three major sandy desertification regions in China and also a representative sandy desertification zone of Qinghai-Tibet Plateau. Accordingly, it is an important region for the study of recent sandy desertification processes and formation mechanism. From such aspects as desertified land types, areas and distributions etc., this paper analyses in detail the sandy desertification status on North Tibet Plateau,and qualitatively and quantitatively deals with the main factors that affect recent sandy desertification processes and the driving mechanism. Research results show that North Tibet Plateau is an important sandy desertification region in China characterized with large desertified land areas, diversified types,high severity, extensive distributions and serious damages. Sandy desertification occurrence and development resulted from combined effects of natural factors, anthropogenic factors, natural processes and man-made processes, of which climatic change is the main driving force.

  15. Lake overspill and onset of fluvial incision in the Iranian Plateau: Insights from the Mianeh Basin

    Science.gov (United States)

    Heidarzadeh, Ghasem; Ballato, Paolo; Hassanzadeh, Jamshid; Ghassemi, Mohammad R.; Strecker, Manfred R.

    2017-07-01

    Orogenic plateaus represent a prime example of the interplay between surface processes, climate, and tectonics. This kind of an interplay is thought to be responsible for the formation, preservation, and, ultimately, the destruction of a typical elevated, low-internal relief plateau landscape. Here, we document the timing of intermontane basin filling associated with the formation of a low-relief plateau morphology, followed by basin opening and plateau-flank incision in the northwestern Iranian Plateau of the Arabia-Eurasia collision zone. Our new U-Pb zircon ages from intercalated volcanic ashes in exposed plateau basin-fill sediments from the most external plateau basin (Mianeh Basin) document that the basin was internally drained at least between ∼7 and 4 Ma, and that from ∼5 to 4 Ma it was characterized by an ∼2-km-high and ∼0.5-km-deep lake (Mianeh paleolake), most likely as a result of wetter climatic conditions. At the same time, the eastern margin of the Mianeh Basin (and, therefore, of the Iranian Plateau) experienced limited tectonic activity, as documented by onlapping sediments and smoothed topography. The combination of high lake level and subdued topography at the plateau margin led to lake overspill, which resulted in the cutting of an ∼1-km-deep bedrock gorge (Amardos) by the Qezel-Owzan River (QOR) beginning at ∼4 Ma. This was associated with the incision of the plateau landscape and the establishment of fluvial connectivity with the Caspian Sea. Overall, our study emphasizes the interplay between surface and tectonic processes in forming, maintaining, and destroying orogenic plateau morphology, the transitional nature of orogenic plateau landscapes on timescales of 106 yr, and, finally, the role played by overspilling in integrating endorheic basins.

  16. EIRP Characterization of Electrically Large Wireless Equipment with Integrated Signal Generator in a Compact Environment

    Directory of Open Access Journals (Sweden)

    Soon-Soo Oh

    2015-01-01

    Full Text Available We describe a measurement technique to characterize the equivalent isotropically radiated power (EIRP of electrically large wireless equipment in a compact environment. A modified phase-measurement method was proposed and, thus, the separation of the signal generator and radiating element was not required during the measurement. A Fresnel-to-far-field transformation was used for the fast measurement time in a compact anechoic chamber. An experimental verification of the method was carried out in a compact anechoic chamber, where the source-detector separation was approximately 1/5 of the far-field distance. The measured magnitude and phase pattern exhibited only a small error. The EIRP obtained using a Fresnel-to-far-field transformation was compared with a reference value, and the error was within 0.5 dB.

  17. Genomics-informed isolation and characterization of a symbiotic Nanoarchaeota system from a terrestrial geothermal environment.

    Science.gov (United States)

    Wurch, Louie; Giannone, Richard J; Belisle, Bernard S; Swift, Carolyn; Utturkar, Sagar; Hettich, Robert L; Reysenbach, Anna-Louise; Podar, Mircea

    2016-07-05

    Biological features can be inferred, based on genomic data, for many microbial lineages that remain uncultured. However, cultivation is important for characterizing an organism's physiology and testing its genome-encoded potential. Here we use single-cell genomics to infer cultivation conditions for the isolation of an ectosymbiotic Nanoarchaeota ('Nanopusillus acidilobi') and its host (Acidilobus, a crenarchaeote) from a terrestrial geothermal environment. The cells of 'Nanopusillus' are among the smallest known cellular organisms (100-300 nm). They appear to have a complete genetic information processing machinery, but lack almost all primary biosynthetic functions as well as respiration and ATP synthesis. Genomic and proteomic comparison with its distant relative, the marine Nanoarchaeum equitans illustrate an ancient, common evolutionary history of adaptation of the Nanoarchaeota to ectosymbiosis, so far unique among the Archaea.

  18. Computer modeling characterization, and applications of Gallium Arsenide Gunn diodes in radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    El- Basit, Wafaa Abd; El-Ghanam, Safaa Mohamed; Kamh, Sanaa Abd El-Tawab [Electronics Research Laboratory, Physics Department, Faculty of Women for Arts, Science and Education, Ain-Shams University, Cairo (Egypt); Abdel-Maksood, Ashraf Mosleh; Soliman, Fouad Abd El-Moniem Saad [Nuclear Materials Authority, Cairo (Egypt)

    2016-10-15

    The present paper reports on a trial to shed further light on the characterization, applications, and operation of radar speed guns or Gunn diodes on different radiation environments of neutron or γ fields. To this end, theoretical and experimental investigations of microwave oscillating system for outer-space applications were carried out. Radiation effects on the transient parameters and electrical properties of the proposed devices have been studied in detail with the application of computer programming. Also, the oscillation parameters, power characteristics, and bias current were plotted under the influence of different γ and neutron irradiation levels. Finally, shelf or oven annealing processes were shown to be satisfactory techniques to recover the initial characteristics of the irradiated devices.

  19. Computer Modeling, Characterization, and Applications of Gallium Arsenide Gunn Diodes in Radiation Environments

    Directory of Open Access Journals (Sweden)

    Wafaa Abd El-Basit

    2016-10-01

    Full Text Available The present paper reports on a trial to shed further light on the characterization, applications, and operation of radar speed guns or Gunn diodes on different radiation environments of neutron or γ fields. To this end, theoretical and experimental investigations of microwave oscillating system for outer-space applications were carried out. Radiation effects on the transient parameters and electrical properties of the proposed devices have been studied in detail with the application of computer programming. Also, the oscillation parameters, power characteristics, and bias current were plotted under the influence of different γ and neutron irradiation levels. Finally, shelf or oven annealing processes were shown to be satisfactory techniques to recover the initial characteristics of the irradiated devices.

  20. Characterizing the Role of Nanoparticle Design on Tumor Transport and Stability in the Extracellular Environment

    Science.gov (United States)

    Albanese, Alexandre

    Nanotechnology has emerged as an exciting strategy for the delivery of diagnostic and therapeutic agents into established tumors. Advancements in nanomaterial synthesis have generated an extensive number of nanoparticle designs made from different materials. Unfortunately, it remains impossible to predict a design's effectiveness for in vivo tumor accumulation. Little is known about how a nanoparticle's morphology and surface chemistry affect its interactions with cells and proteins inside the tumor tissue. This thesis focuses on the development of in vitro experimental tools to evaluate how nanoparticle design affects transport in a three-dimensional tumor tissue and stability in the tumor microenvironment. Nanoparticle transport was evaluated using a novel 'tumor-on-a-chip' system where multicellular tumor spheroids were immobilized in a microfluidic channel. This setup created a three-dimensional tumor environment displaying physiological cell density, extracellular matrix organization, and interstitial flow rates. The tumor-on-a-chip demonstrated that accumulation of nanoparticles was limited to diameters below 110 nm and was improved by receptor targeting. Nanoparticle stability in the tumor microenvironment was evaluated using media isolated from different tumor cell lines. Nanoparticle diameter and surface chemistry were important determinants of stability in cancer cell-conditioned media. Small nanoparticles with unstable surface chemistries adsorbed cellular proteins on their surface and were prone to aggregation. Nanoparticle aggregation altered cellular interactions leading to changes in cell uptake. Using a novel technique to generate different aggregate sizes possessing a uniform surface composition, it was determined that aggregation can change receptor affinity, cell internalization mechanisms and sub-cellular sequestration patterns. Data from this thesis characterize the behavior of nanoparticles within modeled tumor environments and provide some

  1. Geophysical and geochemical characterization and delineation of a crude oil spill in a highly saline environment

    Science.gov (United States)

    Ross, Cameron Stuart

    Geophysical and geochemical methods were used at Grand Terre 1 (GT1) Island off the coast of Louisiana, an island that had been heavily contaminated with crude oil associated with the April 2010 BP Deepwater Horizon oil spill. Electrical methods and aqueous geochemistry have proven sensitive in the detection of contaminates, as well as the biological and chemical processes associated with the biodegradation of hydrocarbons in the subsurface. However, to the author's knowledge, all of these studies have dealt with mature (or aged) spills within a freshwater environment. The BP Deepwater Horizon oil spill therefor provided a unique opportunity to not only use traditional geophysical and geochemical methods to characterize and delineate fresh crude oil in a highly saline environment and to capture the early time biogeophysical signals resulting from the physical, chemical, and microbial transformation of crude oil in a highly saline environment. Electrical resistivity and electromagnetic methods were used. Barometric pressure, temperature, electrical conductivity, and water level values for the shallow groundwater were continuously logged. Geochemical analysis was performed on water samples collected from piezometers networks installed in the impacted, transitional, and background areas. Sediment cores were retrieved throughout the site and used for grain size analysis, magnetic susceptibility, total organic and inorganic carbon, and x-ray fluorescence. Soil samples were collected for microbial analyses from the impacted and background areas. Microcosms were set up to determine the microbial diversity analysis was used to determine microbial community composition, and biodegradation potential of indigenous populations. Based on the geochemical, microbial, and soil analysis, the relatively higher apparent resistivity anomaly observed between the depths of 0.20 m to 1.20 m bgs could be explained by two scenarios(1): elevated resistivity was caused by gas in the

  2. Characterization of Insecticidal Genes of Bacillus thuringiensis Strains Isolated from Arid Environments.

    Science.gov (United States)

    Abulreesh, Hussein H; Osman, Gamal E H; Assaeedi, Abdulrahman S A

    2012-09-01

    This study aimed at characterizing the insecticidal genes of eight Bacillus thuringiensis isolates that were recovered from the local environment of western Saudi Arabia. The screening for the presence of lepidopteran-specific cry1A family and vip3A genes, dipteran-specific cry4 family and coleopteran-specific cry3A, vip1A and vip2A genes, was carried out by PCR. All eight isolates produced PCR products that confirmed the presence of cry1Aa, cry1Ab, cry1Ac, cry4A, cry4B genes, but not cry3A, vip1A and vip2A genes. However, three isolates only were found to carry vip3A genes as revealed by PCR. The observation of cry1 and cry4 genes suggests that these eight isolates may have dual activity against Lepidoptera and Diptera species, while three isolates possessed vip3 genes in addition to cry1 and cry4 which suggests that these three isolates have toxic crystals and vegetative proteins. The results of this study are interesting in the sense that they may help developing new strategies for controlling insects of economic and medical importance in Saudi Arabia, using B. thuringiensis strains that naturally exist in the local environment instead of the current control strategies that are based solely on chemical insecticides.

  3. Isolation and characterization of pigmented bacteria showing antimicrobial activity from Malaysian marine environment

    Directory of Open Access Journals (Sweden)

    Ahmad, A.

    2013-01-01

    Full Text Available Aims: Natural products play a prominent role in the discovery of leads for the development of drugs in the treatment ofhuman diseases. Much of nature remains to be explored, especially marine and microbial environments.Methodology and results: Fifty-five pigmented marine bacteria were isolated from sponges, seawater, mangrovesediment, sea cucumber and mussel from different coastal area of Malaysia. The antimicrobial activities of thesebacteria were investigated by disk diffusion method against pathogenic bacteria. Out of 55 isolates, 18 isolates exhibitedantimicrobial activity, which based on morphological characterization, 53% of them were Gram positive and 47% wereGram negative. All active isolates were able to tolerate more than 4% NaCl in the nutrient agar medium that indicatedthey were autochthonous to marine environment and moderate salt tolerant in nature. Molecular identification of isolatesby the strong antimicrobial activities indicates that isolates WPRA3 (JX020764 and SM11-3j belong to genus Serratiaand isolate SDPM1 (JQ083392 belongs to genus Zooshikella.Conclusion, significance and impact of study: The results of present study revealed that the active isolates arepotential producer of antimicrobial secondary metabolites and might be utilized as drug candidate.

  4. Characterizing spatial and temporal variability of dissolved gases in aquatic environments with in situ mass spectrometry.

    Science.gov (United States)

    Camilli, Richard; Duryea, Anthony N

    2009-07-01

    The TETHYS mass spectrometer is intended for long-term in situ observation of dissolved gases and volatile organic compounds in aquatic environments. Its design maintains excellent low mass range sensitivity and stability during long-term operations, enabling characterization of low-frequency variability in many trace dissolved gases. Results are presented from laboratory trials and a 300-h in situ trial in a shallow marine embayment in Massachusetts, U.S.A. This time series consists of over 15000 sample measurements and represents the longest continuous record made by an in situ mass spectrometer in an aquatic environment. These measurements possess sufficient sampling density and duration to apply frequency analysis techniques for study of temporal variability in dissolved gases. Results reveal correlations with specific environmental periodicities. Numerical methods are presented for converting mass spectrometer ion peak ratios to absolute-scale dissolved gas concentrations across wide temperature regimes irrespective of ambient pressure, during vertical water column profiles in a hypoxic deep marine basin off the coast of California, U.S.A. Dissolved oxygen concentration values obtained with the TETHYS instrument indicate close correlation with polarographic oxygen sensor data across the entire depth range. These methods and technology enable observation of aquatic environmental chemical distributions and dynamics at appropriate scales of resolution.

  5. Analytical and experimental studies of leak location and environment characterization for the international space station

    Energy Technology Data Exchange (ETDEWEB)

    Woronowicz, Michael; Blackmon, Rebecca; Brown, Martin [Stinger Ghaffarian Technologies, Inc, 7701 Greenbelt Rd, Greenbelt, MD 20770 (United States); Abel, Joshua; Hawk, Doug [Alliant Techsystems, Inc, 5050 Powder Mill Road, Beltsville, Maryland 20705 (United States); Autrey, David; Glenn, Jodie [Lockheed Martin, 1300 Hercules, Houston, TX 77058 (United States); Bond, Tim; Buffington, Jesse [NASA Johnson Space Flight Center, 2101 NASA Pkwy, Houston, TX 77058 (United States); Cheng, Edward; Ma, Jonathan; Rossetti, Dino [Conceptual Analytics, 8209 Woburn Abbey Rd, Glenn Dale, MD 20769 (United States); DeLatte, Danielle [ASRC Federal Space and Defense, 7000 Muirkirk Meadows Drive, Suite 100, Beltsville, MD 20705 (United States); Garcia, Kelvin; Mohammed, Jelila; Montt de Garcia, Kristina; Perry, Radford [NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771 (United States); Tull, Kimathi [Jackson and Tull, 7375 Executive Pl, Lanham, MD 20706 (United States); Warren, Eric [Wyle STE Group, 1290 Hercules Ave, Houston, TX 77058-2769 (United States)

    2014-12-09

    The International Space Station program is developing a robotically-operated leak locator tool to be used externally. The tool would consist of a Residual Gas Analyzer for partial pressure measurements and a full range pressure gauge for total pressure measurements. The primary application is to demonstrate the ability to detect NH{sub 3} coolant leaks in the ISS thermal control system. An analytical model of leak plume physics is presented that can account for effusive flow as well as plumes produced by sonic orifices and thruster operations. This model is used along with knowledge of typical RGA and full range gauge performance to analyze the expected instrument sensitivity to ISS leaks of various sizes and relative locations (“directionality”). The paper also presents experimental results of leak simulation testing in a large thermal vacuum chamber at NASA Goddard Space Flight Center. This test characterized instrument sensitivity as a function of leak rates ranging from 1 lb{sub m/}/yr. to about 1 lb{sub m}/day. This data may represent the first measurements collected by an RGA or ion gauge system monitoring off-axis point sources as a function of location and orientation. Test results are compared to the analytical model and used to propose strategies for on-orbit leak location and environment characterization using the proposed instrument while taking into account local ISS conditions and the effects of ram/wake flows and structural shadowing within low Earth orbit.

  6. Analytical and experimental studies of leak location and environment characterization for the international space station

    Science.gov (United States)

    Woronowicz, Michael; Abel, Joshua; Autrey, David; Blackmon, Rebecca; Bond, Tim; Brown, Martin; Buffington, Jesse; Cheng, Edward; DeLatte, Danielle; Garcia, Kelvin; Glenn, Jodie; Hawk, Doug; Ma, Jonathan; Mohammed, Jelila; de Garcia, Kristina Montt; Perry, Radford; Rossetti, Dino; Tull, Kimathi; Warren, Eric

    2014-12-01

    The International Space Station program is developing a robotically-operated leak locator tool to be used externally. The tool would consist of a Residual Gas Analyzer for partial pressure measurements and a full range pressure gauge for total pressure measurements. The primary application is to demonstrate the ability to detect NH3 coolant leaks in the ISS thermal control system. An analytical model of leak plume physics is presented that can account for effusive flow as well as plumes produced by sonic orifices and thruster operations. This model is used along with knowledge of typical RGA and full range gauge performance to analyze the expected instrument sensitivity to ISS leaks of various sizes and relative locations ("directionality"). The paper also presents experimental results of leak simulation testing in a large thermal vacuum chamber at NASA Goddard Space Flight Center. This test characterized instrument sensitivity as a function of leak rates ranging from 1 lbm//yr. to about 1 lbm/day. This data may represent the first measurements collected by an RGA or ion gauge system monitoring off-axis point sources as a function of location and orientation. Test results are compared to the analytical model and used to propose strategies for on-orbit leak location and environment characterization using the proposed instrument while taking into account local ISS conditions and the effects of ram/wake flows and structural shadowing within low Earth orbit.

  7. A mismatch characterization and simulation environment for weak-to-strong inversion CMOS transistors

    Science.gov (United States)

    Velarde-Ramirez, J.; Vicente-Sanchez, G.; Serrano-Gotarredona, T.; Linares-Barranco, B.

    2005-06-01

    Mismatch analysis and simulation is crucial for modern analog design with submicron technologies, where transistors tend to be biased in weak and moderate inversion regions because of the down shrinking of power supply voltage. For optimum analog design where speed, power consumption, area, noise, and accuracy need to be carefully traded off, it is crucial to have available a precise estimation of transistor mismatch in order to avoid overdesign and consequently sacrify unnecessarily speed, power consumption, and area. In this paper we will provide experimental mismatch measurements of different 0.35um CMOS technologies. Each technology has been characterized for a large number of transistor sizes (25-30), by sweeping different width and length values. A large number of transistor curves are measured ranging over different possible biasing conditions. A recent mismatch model will be used to fit the data, and extract electrical parameters. Some of those parameters will be used to adjust the measured mismatch. As a result, a set of standard deviations and correlation coefficients result for the statistical characterization of the mismatch responsible parameters. The resulting electrical parameters, and statistical mismatch parameters are then used in the Spectre simulator of Cadence design environment, to implement the mismatch models using the AHDL behavioral level Spectre description language. The paper shows good agreement between measured data, predicted data, and simulated data.

  8. Structural and rheological characterizations of nanoparticles of environment-sensitive hydrophobic alginate in aqueous solution.

    Science.gov (United States)

    Chen, Kai; Li, Jiacheng; Feng, Yuhong; He, Furui; Zhou, Qingfeng; Xiao, Dunchao; Tang, Yiyuan

    2017-01-01

    Amphiphilic polymers that form self-assembled structures in aqueous media have been investigated and used for the diagnosis and therapy of various diseases, including cancer. In our work, a series of environment-sensitive hydrophobic alginates (Ugi-Alg) with various weight-average molecular mass values (Mw~6.7×10(5)-6.7×10(4)g/mol) were synthesized via Ugi reaction. The structure of Ugi-Alg was characterized by (1)HNMR spectrometer. The electrostatic self-assembly of different molecular weight (Mw) and composition (M/G ratio) of Ugi-Alg chain under various Na(+) concentrations, was investigated by dynamic light scattering, electron spin resonance experiments, and transmission electron microscopy. Result showed that by comparing to other Ugi-Alg, the mid-Mw Ugi-Alg (Mw~2.8×10(5)g/mol) could form stable and homogeneous nanoparticles in low Na(+) concentration solution. However, G/M values exerted no obvious effect on nanoparticles structure. Additionally, steady-shear flow, thixotropy and dynamical viscoelasticity tests were performed to characterize the rheological behavior of Ugi-Alg aqueous solutions as influenced by Mw and M/G ratio. All of the samples exhibited a non-Newtonian shear-thinning behavior above a critical shear rate (γ̇c2). The greater the Mw, the more sensitive the temperature-dependent behavior will be. The upward-downward rheograms showed that all of the systems evaluated in this study displayed a hysteresis loop, indicating a strong thixotropic behavior, and the thixotropic of mid-Mw Ugi-Alg was the strongest. The dynamical viscoelastic properties were characterized by oscillatory frequency sweep, revealing the gel-like viscoelastic behavior of mid-low Ugi-Alg and the fluid-like viscoelastic behavior of high-Mw Ugi-Alg. Copyright © 2016. Published by Elsevier B.V.

  9. Characterization of small mammal populations inhabiting the B-C cribs environs

    Energy Technology Data Exchange (ETDEWEB)

    Hedlund, J.D.; Rogers, L.E.

    1976-12-01

    The purpose of this study was to document the current status of small mammal populations inhibiting the 200 Area plateau near the B-C Crib management area and to compare them with populations inhabiting a protected (control) area within the confines of the Hanford ALE Reserve. Sampling sessions were conducted over two field seasons (1974 and 1975). A total of five species was detected within intensive study areas. These included the Great Basin pocket mouse (Perognathus parvus), deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), sagebrush vole (Lagurus curtatus), and western harvest mouse (Reithrodontomys megalotis). These species are probably representative of those found throughout the area at this particular elevation. Townsends ground squirrel (Spermophilus townsendii) also occurs in this area but did not occur on the sampling plots during the study duration. The pocket mouse was the only species present in sufficient numbers to permit a detailed analysis of population parameters. A discussion concerning the role small mammals play in mineral cycling and energy transfer processes is included along with a diagram depicting food web interrelationships for consumers inhabiting the 200 Area plateau region. Estimates of small mammal density and biomass provided in this document are needed for an overall understanding of the role biota play in the transfer of waste nuclides.

  10. Monuments of the Giza Plateau

    Science.gov (United States)

    Ruggles, Clive L. N.

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

  11. The Colorado Plateau IV: shaping conservation through science and management

    Science.gov (United States)

    Wakeling, Brian F.; Sisk, Thomas D.; van Riper, Charles

    2010-01-01

    Roughly centered on the Four Corners region of the southwestern United States, the Colorado Plateau covers some 130,000 square miles of sparsely vegetated plateaus, mesas, canyons, arches, and cliffs in Arizona, Utah, Colorado, and New Mexico. With elevations ranging from 3,000 to 14,000 feet, the natural systems found within the plateau are dramatically varied, from desert to alpine conditions. This book focuses on the integration of science and resource management issues in this unique and highly varied environment. Broken into three subsections, this volume addresses conservation biology, biophysical resources, and inventory and monitoring concerns. The chapters range in content, addressing conservation issues–past, present, and future–on the Colorado Plateau, measurement of human impacts on resources, grazing and wildland-urban interfaces, and tools and methods for monitoring habitats and species. An informative read for people interested in the conservation and natural history of the region, the book will also serve as a valuable reference for those people engaged in the management of cultural and biological resources of the Colorado Plateau, as well as scientists interested in methods and tools for land and resource management throughout the West.

  12. Excessive afforestation and soil drying on China's Loess Plateau

    Science.gov (United States)

    Zhang, Shulei; Yang, Dawen

    2017-04-01

    Afforestation and deforestation are human disturbances to vegetation, which have profound impacts on regional eco-hydrological processes, the water and carbon cycles, and consequently, ecosystem sustainability. Since 1999, large scale revegetation has been carried out across China's Loess Plateau following the "Grain-to-Green Program" implemented by the Chinese government. This revegetation, particularly with forest, has caused negative eco-hydrological consequences, including streamflow decline and soil drying. Here, we have used "ecosystem optimality theory" and satellite observations, to assess the water balance under the climate-defined optimal and actual vegetation cover during 1982-2010 and its responses to future climate change (2011-2050) over the Loess Plateau. Results show that the current vegetation cover (0.48 on average) has already exceeded the climate-defined optimal cover (0.43 on average) in the most recent decade, especially in the middle-to-east Loess Plateau, indicating that it is the widespread over-planting, which is primarily responsible for soil drying in the area. In addition, both the optimal vegetation cover and soil moisture tend to decrease under future climate scenarios. Our findings suggest that further revegetation on the Loess Plateau should be applied with caution. To maintain a sustainable eco-hydrological environment in the region, a revegetation threshold should be urgently set, to limit future planting.

  13. Hydrogeologic characterization of Owo and its environs using remote sensing and GIS

    Science.gov (United States)

    Adewumi, Adeniyi JohnPaul; Anifowose, Yekeen Biodun

    2017-09-01

    The application of remote sensing and GIS in groundwater potential characterization has been internationally acclaimed. Owo and its environment lack sufficient groundwater data that will aid proper planning and management of the resource. For this reason, the groundwater potential study of Owo and its environment within the Basement Complex was carried out using remote sensing and GIS. LANDSAT ETM + (Bands 1-8) was acquired and the acquired imageries were processed using image processing software. For drainage mapping, bands 4-3-2 were combined in a RGB (123) format. For lineament extraction, the Digital terrain model (DTM) was generated from the SRTM data. The DTM was used in extracting lineaments in the study area. Groundwater potential of the area was calculated using score values assigned to each parameter studied. Results show that the lineament distribution in the study area is polymodal with peaks between 80°-100°. The East-West fractures are most prominent, with the broad, positive correlation in frequency and length of the lineament, suggesting that they are of geological origin. Lineament density of the area shows that Owo has higher lineament density of about 0.85 km/km2 when compared other part of the study area. The density of lineament in the study area is attributable to the high fracturing that affected the Basement Complex area during the Pan-African Orogeny. In addition, the study further revealed that there are more lineament intersection around the southeastern part of Owo Township and Iyere. These areas are more favourable sites for groundwater accumulation. The drainage density map generated for the study area reveals that there are more rivers around Emure-Owo than other parts of the study area. In conclusion, the groundwater potential of the study area is from low to high.

  14. Characterization of Surface Films Formed During Corrosion of a Pipeline Steel in H2S Environments

    Science.gov (United States)

    Huang, F.; Cheng, P.; Dong, Y. Y.; Liu, J.; Hu, Q.; Zhao, X. Y.; Cheng, Y. Frank

    2017-01-01

    In this work, the surface films formed on an X52 pipeline steel in H2S-containing environments with various pH values and H2S concentrations were characterized by surface analysis techniques and electrochemical impedance spectroscopy. A stoichiometric FeS film is formed during H2S corrosion of the steel. At low pH (e.g., 3.5) and low H2S concentration (e.g., 0.2 mmol/L), the film is primarily crystalline FeS. When the H2S concentration increases to 2 and 20 mmol/L, mackinawite is also formed. At high pH of 5.5 and low H2S concentration of 0.2 mmol/L, the film is amorphous FeS. With the increase in the H2S concentration to 2 and 20 mmol/L, the film changes to crystalline FeS and the mixture of crystalline FeS and mackinawite, respectively. In low-pH solution (pH 3.5), the compact, crystalline FeS is more protective for steel corrosion compared to mackinawite. As the H2S concentration increases, the corrosion is increased. At high pH of 5.5, when the H2S concentration is 0.2 mmol/L, the low corrosivity of the environment causes production of amorphous FeS only. As the H2S concentration is increased, a thick film is generated, reducing somewhat the steel corrosion.

  15. Characterization of Surface Films Formed During Corrosion of a Pipeline Steel in H2S Environments

    Science.gov (United States)

    Huang, F.; Cheng, P.; Dong, Y. Y.; Liu, J.; Hu, Q.; Zhao, X. Y.; Cheng, Y. Frank

    2017-02-01

    In this work, the surface films formed on an X52 pipeline steel in H2S-containing environments with various pH values and H2S concentrations were characterized by surface analysis techniques and electrochemical impedance spectroscopy. A stoichiometric FeS film is formed during H2S corrosion of the steel. At low pH (e.g., 3.5) and low H2S concentration (e.g., 0.2 mmol/L), the film is primarily crystalline FeS. When the H2S concentration increases to 2 and 20 mmol/L, mackinawite is also formed. At high pH of 5.5 and low H2S concentration of 0.2 mmol/L, the film is amorphous FeS. With the increase in the H2S concentration to 2 and 20 mmol/L, the film changes to crystalline FeS and the mixture of crystalline FeS and mackinawite, respectively. In low-pH solution (pH 3.5), the compact, crystalline FeS is more protective for steel corrosion compared to mackinawite. As the H2S concentration increases, the corrosion is increased. At high pH of 5.5, when the H2S concentration is 0.2 mmol/L, the low corrosivity of the environment causes production of amorphous FeS only. As the H2S concentration is increased, a thick film is generated, reducing somewhat the steel corrosion.

  16. Characterization of high-yield performance as affected by genotype and environment in rice

    Institute of Scientific and Technical Information of China (English)

    Song CHEN; Fang-rong ZENG; Zong-zhi PAO; Guo-ping ZHANG

    2008-01-01

    We characterized yield-relevant characters and their variations over genotypes and environments (locations and years) by examining two rice varieties (9746 and Jinfeng) with high yield potential.9746 and Jinfeng were planted in two locations of Shanghai,China,during 2005 and 2006.The results show that there was a large variation in grain yield between locations and years.The realization of high yield potential for the two types of rice was closely related to the improved sink size,such as more panicles per square meter or grains per panicle.Stem and leaf biomasses were mainly accumulated from tillering stage to heading stage,and showed slow decline during grain filling.Meanwhile,some photosynthetic characters including net photosynthesis rate (Pn),leaf area index (LAI),specific leaf area (SLA),fluorescence parameter (maximum quantum yield of PSII,Fv/Fm),chlorophyll content (expressed as SPAD value),as well as nutrient (N,P,K) uptake were also measured to determine their variations over genotypes and environments and their relationships with grain yield.Although there were significant differences between years or locations for most measurements,SLA at tillering and heading stages,Fv/Fm and LAI at heading stage,stem biomass at heading and maturity stages,and leaf nitrogen concentration at tillering and heading stages remained little changed,indicating their pos-sible applications as selectable characters in breeding programs.It was also found that stem nitrogen accumulation at tillering stage is one of the most important and stable traits for high yield formation.

  17. Geotechnologies for the Characterization of Specialty Coffee Environments of Mantiqueira de Minas in Brazil

    Science.gov (United States)

    Alves, H. M. R.; Vieira, T. G. C.; Volpato, M. M. L.; Lacerda, M. P. C.; Borém, F. M.

    2016-06-01

    Land-use/land-cover change (LUCC) is a major cause of environmental transformation. Distant drivers, often associated with emerging markets for specific products, are now being considered one of the main factors of LUCC and are gaining attention in land change science. Consumers show an increasing interest in local and quality food, certified for its origin and its environmental production standards. A kind of agricultural product certification, Geographic Indication, identifies a product as originating from a specific region where a given quality, reputation or characteristic is attributed to its geographical origin. Sustainable land use is potentially an indirect effect of Geographic Indication, as it requires better land management in order to preserve the natural resources associated with the unique characteristics of the certified product. Located in the southern region of the state of Minas Gerais in Brazil is the region of Mantiqueira de Minas, considered one of the most important regions for the production of specialty coffees in Brazil. In 2011, the region's tradition and reputation were recognized with a Geographic Indication, the second given for coffee regions in the country. To explore the full potential of this area for producing coffees with higher quality and meet the growing demand of this new international market, which aggregates value at specialty coffees, it became fundamental to understand the coffee environments of the region, the "terroirs" where these coffees are obtained. Geotechnology can give a significant contribution in filling this gap. This work is part of a research project that made a detailed characterization of the region's coffee agroecosystems. Geotechnologies were employed to map the areas occupied by coffee plantations by using RapidEye satellite images and SPRING and ArcGIS software. All the segments of the environment were characterized and mapped in detail and the relations with coffee quality were evaluated. The results

  18. Fabrication and characterization of ultrathin dextran layers: Time dependent nanostructure in aqueous environments revealed by OWLS.

    Science.gov (United States)

    Saftics, Andras; Kurunczi, Sándor; Szekrényes, Zsolt; Kamarás, Katalin; Khánh, Nguyen Quoc; Sulyok, Attila; Bősze, Szilvia; Horvath, Robert

    2016-10-01

    Surface coatings of the polysaccharide dextran and its derivatives are key ingredients especially in label-free biosensors for the suppression of non-specific binding and for receptor immobilization. Nevertheless, the nanostructure of these ultrathin coatings and its tailoring by the variation of the preparation conditions have not been profoundly characterized and understood. In this work carboxymethylated dextran (CMD) was prepared and used for fabricating ultrathin surface coatings. A grafting method based on covalent coupling to aminosilane- and epoxysilane-functionalized surfaces was applied to obtain thin CMD layers. The carboxyl moiety of the CMD was coupled to the aminated surface by EDC-NHS reagents, while CMD coupling through epoxysilane molecules was performed without any additional reagents. The surface analysis following the grafting procedures consisted of X-ray photoelectron spectroscopy (XPS), attenuated total reflection infrared spectroscopy (ATR-IR), spectroscopic ellipsometry, atomic force microscopy (AFM) and optical waveguide lightmode spectroscopy (OWLS). The XPS and AFM measurements showed that the grafting resulted in a very thin dextran layer of a few nanometers. The OWLS method allowed devising the structure of the interfacial dextran layers by the evaluation of the optogeometrical parameters. The alteration in the nanostructure of the CMD layer with the chemical composition of the silane coverage and the pH of the grafting solution was revealed by in situ OWLS, specifically, lain down chains were found to be prevalent on the surface under neutral and basic conditions on epoxysilylated surfaces. The developed methodologies allowed to design and fabricate nanometer scale CMD layers with well-controlled surface structure, which are very difficult to characterize in aqueous environments using present instrumentations and highly hydrated surface layers.

  19. Progress in the development of MANIC: a monolithic nulling interferometer for characterizing extrasolar environments

    Science.gov (United States)

    Hicks, Brian A.; Cook, Timothy A.; Lane, Benjamin F.; Chakrabarti, Supriya

    2010-07-01

    We present progress in the development of the monolithic achromatic nulling interference coronagraph (MANIC), an optic designed for enabling direct detection and characterization of exoplanetary systems around nearby stars. MANIC is a fully symmetric implementation of a rotational shearing interferometer consisting of fused quartz prisms and a symmetric beamsplitter optically contacted in an arrangement that geometrically flips the fields in the TR and RT arms about orthogonal axes such that upon recombination, a centro-symmetric, theoretically achromatic null is produced. In addition to a small inner working angle (benefits of the compact monolithic design, which make MANIC a competitive alternative to conventional discrete element nullers proposed for imaging exoplanetary environments. Following MANIC's initial fabrication, the path error between its TR and RT arms was measured. This measurement was used to fabricate compensator plates of varying thicknesses that were bonded to the optic to reduce dispersion imbalance, thereby improving broadband nulling performance. In performing this correction, initial OPD was reduced from 949 +/- 44 nm to 63 +/- 10 nm, which in the absence of any other asymmetries, corresponds to an increase in a 107 R-band (λc = 648 nm) nulling bandpass from monochromatic to 25%, or at the 106 level, from 5% to 50%. Current benchtop laser and polychromatic nulling strategies are described. The potential science return from using MANIC on a sub-orbital platform is discussed.

  20. Characterizing pedagogical practices of university physics students in informal learning environments

    Directory of Open Access Journals (Sweden)

    Kathleen A. Hinko

    2016-02-01

    Full Text Available [This paper is part of the Focused Collection on Preparing and Supporting University Physics Educators.] University educators (UEs have a long history of teaching physics not only in formal classroom settings but also in informal outreach environments. The pedagogical practices of UEs in informal physics teaching have not been widely studied, and they may provide insight into formal practices and preparation. We investigate the interactions between UEs and children in an afterschool physics program facilitated by university physics students from the University of Colorado Boulder. In this program, physics undergraduates, graduate students, and postdoctoral researchers work with K-8 children on hands-on physics activities on a weekly basis over the course of a semester. We use an activity theoretic framework as a tool to examine situational aspects of individuals’ behavior in the complex structure of the afterschool program. Using this framework, we analyze video of UE-child interactions and identify three main pedagogical modalities that UEs display during activities: instruction, consultation, and participation modes. These modes are characterized by certain language, physical location, and objectives that establish differences in UE-child roles and division of labor. Based on this analysis, we discuss implications for promoting pedagogical strategies through purposeful curriculum development and university educator preparation.

  1. Characterization of Oxide Layer with Precipitates of HANA-6 Exposed in Simulated PWR Primary Water Environment

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hun; Lim, Jea Young; Lee, Sung Yong; Kim, Yoon Ho; Mok, Yong Kyoon [KEPCO NF, Daejeon (Korea, Republic of)

    2016-10-15

    The delayed oxidation behaviors of β-Nb ppts and their amorphization behaviors in HANA-6 and other Zr-base alloys have been frequently reported. On the other hand, although Zr(Nb,Fe)2 ppts could be formed in the HANA-6 alloy due to Fe impurities contained in Zrsponge, the oxidation behavior of Zr(Nb,Fe)2 ppts contained in HANA-6 alloy has not been fully understood. In this study, oxide characteristics of HANA-6 corroded in simulated PWR environment for 165 and 315 days were investigated. And, oxidation behaviors of Zr(Nb,Fe)2 ppts contained in HANA-6 alloy were investigated by TEM with EDS techniques. The superior corrosion property of HANA-6 has been confirmed through corrosion test in simulated PWR water for 387 days. By using TEM/EDS technique, the oxide characteristics with presence of β- Nb (or β-enriched), and ZrNbFe (possibly Zr(Nb,Fe){sub 2}) ppts have been characterized as follows. 1. Delayed oxidation behaviors of β-Nb and Zr(Nb,Fe){sub 2} ppts and their amorphization due to oxidation were observed from TEM/EDS analyses. 2. The oxide layers having crystallite and partially amorphous ppts were slightly increased with increasing corrosion test time from 165 days to 315 days. 3. In outer oxide layer, Fe in Zr(Nb,Fe){sub 2} ppt was depleted and dissolved to outer layer of ppt and bulk oxide layer.

  2. Characterizing pedagogical practices of university physics students in informal learning environments

    Science.gov (United States)

    Hinko, Kathleen A.; Madigan, Peter; Miller, Eric; Finkelstein, Noah D.

    2016-06-01

    [This paper is part of the Focused Collection on Preparing and Supporting University Physics Educators.] University educators (UEs) have a long history of teaching physics not only in formal classroom settings but also in informal outreach environments. The pedagogical practices of UEs in informal physics teaching have not been widely studied, and they may provide insight into formal practices and preparation. We investigate the interactions between UEs and children in an afterschool physics program facilitated by university physics students from the University of Colorado Boulder. In this program, physics undergraduates, graduate students, and postdoctoral researchers work with K-8 children on hands-on physics activities on a weekly basis over the course of a semester. We use an activity theoretic framework as a tool to examine situational aspects of individuals' behavior in the complex structure of the afterschool program. Using this framework, we analyze video of UE-child interactions and identify three main pedagogical modalities that UEs display during activities: instruction, consultation, and participation modes. These modes are characterized by certain language, physical location, and objectives that establish differences in UE-child roles and division of labor. Based on this analysis, we discuss implications for promoting pedagogical strategies through purposeful curriculum development and university educator preparation.

  3. Surface, Water and Air Biocharacterization - A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Pierson, Duane L.; Ott, C. Mark; Cruz, Patricia; Buttner, Mark P.

    2009-01-01

    A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft (SWAB) will use advanced molecular techniques to comprehensively evaluate microbes on board the space station, including pathogens (organisms that may cause disease). It also will track changes in the microbial community as spacecraft visit the station and new station modules are added. This study will allow an assessment of the risk of microbes to the crew and the spacecraft. Research Summary: Previous microbial analysis of spacecraft only identify microorganisms that will grow in culture, omitting greater than 90% of all microorganisms including pathogens such as Legionella (the bacterium which causes Legionnaires' disease) and Cryptosporidium (a parasite common in contaminated water) The incidence of potent allergens, such as dust mites, has never been systematically studied in spacecraft environments and microbial toxins have not been previously monitored. This study will use modern molecular techniques to identify microorganisms and allergens. Direct sampling of the ISS allows identification of the microbial communities present, and determination of whether these change or mutate over time. SWAB complements the nominal ISS environmental monitoring by providing a comparison of analyses from current media-based and advanced molecular-based technologies.

  4. Characterization of organic matter deposited in the oriental zone from Moknine hypersaline environment, oriental Tunisia

    Institute of Scientific and Technical Information of China (English)

    Raja CHAIRI; Zohra EL ASMI DJELLOULI

    2005-01-01

    The geochemistry data show that the total organic carbon (TOC) contents are high in the surface sediments in the eastern part of the Moknine's Sebkha. Low decreasing of organic matter (OM) with increasing depth indicates the good preservation of OM in modern sediments. "Lignite levels" inserted in the sand sequence and deposited at the edge and in the intermediate zone are considered as lithologic and organic markers. It is characterized by high TOC and poor hydrogen index (HI), indicating a higher plant origin and good preservation of OM in thin beds under anoxic condition.In all samples low values of HI are typical for strong terrigenous input in the Sebkha. Gas chromatography (GC) of saturate fraction showed that OM in the border zone is provided from plants but in the central zone OM is a mixture of terrestrial fraction and little fraction from microalgae. The study of free lipids indicated that this environment was influenced by intense bacterial and microbial activities, as evidenced by the abundance of n-alkanes and nC 18-nC 22.

  5. Biodiversity and conservation in the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Tibetan Plateau (Qinghai-Xizang Plateau) is a unique biogeographic region in the world, where various landscapes, altitudinal belts, alpine ecosystems, and endangered and endemic species have been developed. A total of 26 altitudinal belts, 28 spectra of altitudinal belts, 12,000 species of vascular plant, 5,000 species of epiphytes, 210 species of mammals, and 532 species of birds have been recorded. The plateau is also one of the centers of species formation and differentiation in the world. To protect the biodiversity of the plateau, about 80 nature reserves have been designated, of which 45 are national or provincial, covering about 22% of the plateau area. Most of the nature reserves are distributed in the southeastern plateau. Recently, the Chinese government has initiated the "Natural Forests Protection Project of China,' mainly in the upper reaches of the Yangtze and Yellow rivers. "No logging" policies have been made and implemented for these areas.

  6. 滇东高原地理环境分异与城镇上山空间资源研究*%Geographic environment of the east plateau of Yunnan Province and spatial resources for constructing “Hill Towns”

    Institute of Scientific and Technical Information of China (English)

    王嘉学; 王教元; 肖梦景; 余洁芳

    2014-01-01

    “The construction of hill towns”is now a very important strategy to protect the limited high-quality arable land of Yunnan Province,whose foundation is based on the scale and location of the spacial resources.Based on a study of the different types of landforms with RS and GIS,this re-search gives a spatial analysis of the geographic information of east Yunnan.The results show that the total space that matches the requirement of urbanization is 217.23 km2 ,which means the quantity of the low hills and basins of the plateau is fairly adequate,which can almost meet the needs of such ur-banization.But these resources are scattered in a wide area and there is a lack of large exploitable land.It concludes that the implementation of the strategy of “the construction of hill towns”is possi-ble in the plateau of east Yunnan but the mountain exploitation is a very hard task.%“城镇上山”是云南近年来为保护为数不多的坝区优质耕地而实施的重大战略,空间资源的规模、位置等是城镇上山的基础。本研究在认识滇东高原不同地貌小区地理环境特征和识别城镇上山地理环境约束条件的基础上,利用 RS和 GIS技术,获取相关地理环境信息并进行空间分析。结果表明,滇东高原城镇上山的空间资源总量为217.23km2,且与城镇化发展趋势及要求在空间上大致吻合,即城镇化发展迅速、城镇上山需求量大的原上缓丘盆地小区和斜坡台地丘陵小区空间资源量较大。但城镇上山空间资源相对较为分散,连片分布斑块不多且面积不大。这意味着滇东高原城镇上山战略的推进,可节约的优质耕地数量是相当可观的,但上山过程中的山地整理任务仍十分繁重。

  7. Instrument developments for chemical and physical characterization, mapping and sampling of extreme environments (Antarctic sub ice environment)

    Science.gov (United States)

    Vogel, S. W.; Powell, R. D.; Griffith, I.; Lawson, T.; Schiraga, S.; Ludlam, G.; Oen, J.

    2009-12-01

    A number of instrumentation is currently under development designed to enable the study of subglacial environments in Antarctica through narrow kilometer long boreholes. Instrumentation includes: - slim line Sub-Ice ROV (SIR), - Geochemical Instrumentation Package for Sub Ice Environments (GIPSIE) to study geochemical fluxes in water and across the sediment water interface (CO2, CH4, dO, NH4, NO3, Si, PO4, pH, redox, T, H2, HS, O2, N2O, CTD, particle size, turbidity, color camera, current meter and automated water sampler) with real-time telemetry for targeted sampling, - long term energy-balance mooring system, - active source slide hammer sediment corer, and - integration of a current sensor into the ITP profiler. The instrumentation design is modular and suitable for remote operated as well as autonomous long-term deployment. Of interest to the broader science community is the development of the GIPSIE and efforts to document the effect of sample recovery from depth on the sample chemistry. The GIPSIE is a geochemical instrumentation package with life stream telemetry, allowing for user controlled targeted sampling of water column and the water sediment interphase for chemical and biological work based on actual measurements and not a preprogrammed automated system. The porewater profiler (pH, redox, T, H2, HS, O2, N2O) can penetrate the upper 50 cm of sediment and penetration is documented with real time video. Associated with GIPSIE is an on-site lab set-up, utilizing a set of identical sensors. Comparison between the insitu measurements and measurements taken onsite directly after samples are recovered from depth permits assessing the effect of sample recovery on water and sediment core chemistry. Sample recovery related changes are mainly caused by changes in the pressure temperature field and exposure of samples to atmospheric conditions. Exposure of anaerobic samples to oxygen is here a specific concern. Recovery from depth effects in generally p

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

    Science.gov (United States)

    Li, Qiang; Wang, Xiaoming

    2015-01-01

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

  9. Molecular characterization of methicillin resistant Staphylococcus aureus isolated from hospitals environments and patients in Northern Palestine

    Directory of Open Access Journals (Sweden)

    Ghaleb Adwan

    2015-09-01

    Full Text Available BACKGROUND: Staphylococcus aureus (S. aureus is considered one of the most common pathogen to humans. Infections caused by this mocroorganism can be acquired through both hospital and community settings. This study was carried out to investigate molecular characterization of MRSA strains isolated from the patients and their environment in two hospitals (Rafidia hospital and Thabet hospital inNorthern Palestine, and to determine the clonal identity between these strains and their possible contribution to nosocomial infections.METHODS: Two hundred sixty five swabbed samples were collected from these hospitals, S. aureus was isolated,  antibiotic resistant genes were Panton–Valentin leukocidin (PVL gene were detected and SCCmec and spA were typed by PCR and/or sequencing.RESULTS: The prevalence of MRSA among S. aureus isolates was 29% and 8.2% in Rafidia hospital and Thabet hospital, respectively. All strains resistant to oxacilllin disk were carried mecA gene. Majority of strains (84.6% carried SCCmec type II (n = 11, type IVa and non-typeable were also detected. In addition, PVL was detected in 2 (14.3% clinical strains. ERIC PCR patterns revealed that 2 strains recovered from patient bed and nasal swab isolated from Thabet Hospital were nontypeable, spA typing showed that they belonged to type t386 and have identical DNA sequences. Other 2 clinical isolates were spa typed, one belonged to clone t044, while the other is new clone not exist in database.CONCLUSIONS: Results may give evidence that environmental contamination possibly contributing to nosocomial infections.

  10. Subsurface Environment Sampler for Improved In Situ Characterization of Subsurface Microbial Communities

    Science.gov (United States)

    Barnhart, E. P.; Ruppert, L. F.; Orem, W. H.; McIntosh, J. C.; Cunningham, A. B.; Fields, M. W.; Hiebert, R.; Hyatt, R.

    2016-12-01

    There is an increasing threat that deep aquifers, an important drinking water resource, may be contaminated by the extraction and transport of fossil fuels. This threat increases the need for improved groundwater monitoring and the ability to predict the extent to which microbial activity may remediate such contamination. The characterization of subsurface microbial communities could provide an ideal biomonitoring tool for the assessment of subsurface contamination due to prokaryotes environmental ubiquity, rapidity of response to environmental perturbation and the important role they play in hydrocarbon degradation and bioremediation. New DNA sequencing technologies provide the opportunity to cost-effectively identify the vast subsurface microbial ecosystem, but use of this new technology is restricted due to issues with sampling. Prior subsurface microbiology studies have relied on core samples that are expensive to obtain hard to collect aseptically and/or ground water samples that do not reflect in situ microbial densities or activities. The development of down-well incubation of sterile sediment with a Diffusive Microbial Sampler (DMS) has emerged as an alternative method to sample subsurface microbial communities that minimizes cost and contamination issues associated with traditional methods. We have designed a Subsurface Environment Sampler with a DMS module that could enable the anaerobic transport of the in situ microbial community from the field for laboratory bioremediation studies. This sampler could provide an inexpensive and standard method for subsurface microbial sampling which would make this tool useful for Federal, State, private and local agencies interested in monitoring contamination or the effectiveness of bioremediation activities in subsurface aquifers.

  11. Characterization of the Scale Model Acoustic Test Overpressure Environment using Computational Fluid Dynamics

    Science.gov (United States)

    Nielsen, Tanner; West, Jeff

    2015-01-01

    The Scale Model Acoustic Test (SMAT) is a 5% scale test of the Space Launch System (SLS), which is currently being designed at Marshall Space Flight Center (MSFC). The purpose of this test is to characterize and understand a variety of acoustic phenomena that occur during the early portions of lift off, one being the overpressure environment that develops shortly after booster ignition. The pressure waves that propagate from the mobile launcher (ML) exhaust hole are defined as the ignition overpressure (IOP), while the portion of the pressure waves that exit the duct or trench are the duct overpressure (DOP). Distinguishing the IOP and DOP in scale model test data has been difficult in past experiences and in early SMAT results, due to the effects of scaling the geometry. The speed of sound of the air and combustion gas constituents is not scaled, and therefore the SMAT pressure waves propagate at approximately the same speed as occurs in full scale. However, the SMAT geometry is twenty times smaller, allowing the pressure waves to move down the exhaust hole, through the trench and duct, and impact the vehicle model much faster than occurs at full scale. The DOP waves impact portions of the vehicle at the same time as the IOP waves, making it difficult to distinguish the different waves and fully understand the data. To better understand the SMAT data, a computational fluid dynamics (CFD) analysis was performed with a fictitious geometry that isolates the IOP and DOP. The upper and lower portions of the domain were segregated to accomplish the isolation in such a way that the flow physics were not significantly altered. The Loci/CHEM CFD software program was used to perform this analysis.

  12. Genetic evidence of paleolithic colonization and neolithic expansion of modern humans on the tibetan plateau.

    Science.gov (United States)

    Qi, Xuebin; Cui, Chaoying; Peng, Yi; Zhang, Xiaoming; Yang, Zhaohui; Zhong, Hua; Zhang, Hui; Xiang, Kun; Cao, Xiangyu; Wang, Yi; Ouzhuluobu; Basang; Ciwangsangbu; Bianba; Gonggalanzi; Wu, Tianyi; Chen, Hua; Shi, Hong; Su, Bing

    2013-08-01

    Tibetans live on the highest plateau in the world, their current population size is approximately 5 million, and most of them live at an altitude exceeding 3,500 m. Therefore, the Tibetan Plateau is a remarkable area for cultural and biological studies of human population history. However, the chronological profile of the Tibetan Plateau's colonization remains an unsolved question of human prehistory. To reconstruct the prehistoric colonization and demographic history of modern humans on the Tibetan Plateau, we systematically sampled 6,109 Tibetan individuals from 41 geographic populations across the entire region of the Tibetan Plateau and analyzed the phylogeographic patterns of both paternal (n = 2,354) and maternal (n = 6,109) lineages as well as genome-wide single nucleotide polymorphism markers (n = 50) in Tibetan populations. We found that there have been two distinct, major prehistoric migrations of modern humans into the Tibetan Plateau. The first migration was marked by ancient Tibetan genetic signatures dated to approximately 30,000 years ago, indicating that the initial peopling of the Tibetan Plateau by modern humans occurred during the Upper Paleolithic rather than Neolithic. We also found evidences for relatively young (only 7-10 thousand years old) shared Y chromosome and mitochondrial DNA haplotypes between Tibetans and Han Chinese, suggesting a second wave of migration during the early Neolithic. Collectively, the genetic data indicate that Tibetans have been adapted to a high altitude environment since initial colonization of the Tibetan Plateau in the early Upper Paleolithic, before the last glacial maximum, followed by a rapid population expansion that coincided with the establishment of farming and yak pastoralism on the Plateau in the early Neolithic.

  13. Optical extinction spectrum of a single metal nanoparticle: Quantitative characterization of a particle and of its local environment

    Science.gov (United States)

    Muskens, O. L.; Billaud, P.; Broyer, M.; Del Fatti, N.; Vallée, F.

    2008-11-01

    Optical absorption spectroscopy of a single metal nanoparticle is used to characterize its properties and to obtain quantitative information on its local environment. Experiments were performed using the spatial modulation spectroscopy (SMS) technique on 16 nm mean diameter gold nanoparticles embedded in different medium (i.e., deposited on glass or embedded in a polymer layer). Extraction of the nanoparticle characteristics and determination of the dielectric constant of its environment are discussed, focusing on the impact of the particle shape assumption. The refractive index of the local environment deduced from these measurements shows large particle-to-particle variation, yielding information about fluctuations of the dielectric properties of the surrounding medium on a nanometric scale, inaccessible in ensemble measurements. The influence of the environment of a nanoparticle on its optically extracted geometry and its surface plasmon resonance broadening by surface effect are also studied at a single-particle level.

  14. Exploration in Newnes Plateau, NSW

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, P.; McQuade, C. [Pasminco Port Pirie Smelter, NSW (Australia)

    1999-06-01

    Underground coal mining operations in the Western Coalfields of NSW extend into the Newnes Plateau area. The Newnes Plateau area is known for its floral diversity and distinctive topography. A quantitative flora assessment concerning rehabilitation performance of exploration sites was undertaken to refine the environmental component of the exploration process and identify practices that may assist in an improved rate of regeneration within disturbed areas. This article briefly summarises the method and key outcomes of the study, undertaken as part of an Honours Degree program. Surveys of sites showed that plant height was reduced due to vehicle traffic compacting soil, and this also led to a reduced number of plant species and a reduced number of seedlings germinating. Percentage litter cover was found to be positively correlated with the number of species on the sites and the percent plant cover of the regenerating vegetation, shallow surface ripping is recommended to relieve soil compaction. Seeds should be collected from exploration sites prior to disturbance, particularly of species like Banksia and Haken that retain their seed on the plant. Seed should then be dispersed after work has finished. 1 fig., 2 photos.

  15. Variations of stable isotopic compositions in precipitation on the Tibetan Plateau and its adjacent regions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    There is no temperature effect in the southern Tibetan Plateau and South Asia to the south of the Tanggula Mountains. Amount effect has been observed at a few sampling stations accounting for about a half of the statistical stations. There is notable temperature effect in the middle and northern Tibetan Plateau and its adjacent Central Asia to the north of the Tanggula Mountains. Because vapor directly originates from low-latitude oceans, the relative heavy ( 18O with small variation characterizes the rainfall in South Asia. A sharp depletion of the stable isotopic compositions in precipitation takes place from Kyangjin on the southern slope of the Himalayas to the Tanggula Mountains in the middle plateau. From the Tanggula Mountains to the northern Tibetan Plateau, the ( 18O in precipitation increases with increasing latitude.

  16. The Transformation of Agricultural Development towards a Sustainable Future from an Evolutionary View on the Chinese Loess Plateau: A Case Study of Fuxian County

    OpenAIRE

    Yanjun Guo; Yansui Liu; Qi Wen; Yurui Li

    2014-01-01

    The Loess Plateau in China receives lots of attention from around the world. The expansion of bad agricultural practices for hundreds of years aggravated the soil erosion on the Loess Plateau, however, and a lot of efforts were and are being made to reduce the serious soil erosion as well as regional poverty. Agricultural development of the Loess Plateau is still confronted with intricate challenges such as food concerns, environment concerns, and regional poverty. The strategy of developmen...

  17. Combined geophysical and petrophysical characterization to support a hydrogeological model of a coastal environment

    Science.gov (United States)

    Burschil, Thomas; Wiederhold, Helga; Scheer, Wolfgang; Kirsch, Reinhard; Krawczyk, Charlotte M.

    2014-05-01

    Global warming affects the water cycle by changing precipitation/evaporation and raising sea level. Especially groundwater systems in sensitive environments, such as coastal areas or barrier islands, have to be evaluated with respect to the potential reduction of water quality, e.g. salinization by saltwater intrusion (Hinsby et al., 2012). To assess these hazards using groundwater modeling we need a strong base of hydraulic and hydrogeological information. The use of integrated geophysical methods, in combination with a petrophysical characterization, provides a reliable architecture for groundwater modeling. Within the EU-project CLIWAT, we investigated the hydrogeological situation of the North Sea island of Föhr in Schleswig-Holstein (Germany). The island was mainly formed during glaciations in Pleistocene Series, especially Saalian and Weichselian Stages. These deposits remain as a Geest core in the southern central part, and house a freshwater lens that is used for the local water supply. To investigate the architecture of the fresh water lens, we carried out several surveys with airborne electromagnetic (AEM), seismic reflection, and borehole methods. To enhance the AEM resistivity model we inverted the data with a-priori constraints from seismic reflections (Burschil et al., 2012a). This constrained inversion leads to, among other things, a separation of two aquifers by resistivity data. Additionally, from borehole logs, vertical seismic profiles (VSP), and nearby AEM inversion point models we are able to petrophysically characterize different lithological categories regarding resistivity and seismic velocity. Subsurface glacial structures, e.g. buried valleys and a push moraine complex, are mapped down to 150 m below sea level. Below this rather horizontal features indicate Tertiary layers. Geophysically determined petrophysical values were correlated with lithological categories to enhance the interpretation of geophysical data. In this way, we expose

  18. Characterizing supernova remnant and molecular cloud interaction environments using Class I methanol (CH3OH) masers

    Science.gov (United States)

    McEwen, Bridget C.

    Astronomical masers are useful probes of the physical conditions of the gas in which they are formed. Masers form under specific physical conditions and therefore, can be used to trace distinct environments, for example, star forming regions (SFRs), supernova remnants (SNRs), evolved stars, and outflows. In particular, collisionally excited 36 and 44 GHz methanol (CH3OH) and 1720 MHz hydroxl (OH) masers are found associated with gas shocked by the interaction between SNRs and neighboring molecular clouds (MCs). The overall goal of my thesis research is to combine modeling and observations to characterize the properties and formation of Class I CH3OH masers in these SNR/MC interaction regions. Developing a general model of the distribution of maser emission in these regions in all SNRs interacting with MCs will aid in the understanding of different processes that may be triggered through these interactions, namely induced star formation (SF) and cosmic ray (CR) acceleration. More accurate information on the density (and density gradients) in these turbulent regions could, for example, be used as inputs or constraints for models of galactic SNR CR acceleration and help explain if conditions are conducive for SF. In this thesis, I present results from calculations of the physical conditions necessary for the occurrence of collisionally pumped Class I 36, 44, 84, and 95 GHz CH3OH maser lines near SNRs, using an escape probability and level population code. The modeling shows that given a sufficient CH3OH abundance, CH3OH maser emission arises over a wide range of densities and temperatures, with optimal conditions at 10 4 sample of SNRs with previous and recent CH 3OH maser detections (G1.4-0.1, W28, Sgr A East, G5.7-0.0, W44, and W51C). I also discuss how detections of CH3OH masers can be used along with other maser tracers, i.e. H2O masers, to pinpoint sights of SF near SNRs. Furthermore, I will discuss the close spatial and kinematic correlation of CH3OH masers in

  19. A review of microbial diversity in polar terrestrial environments

    Directory of Open Access Journals (Sweden)

    Weidong Kong

    2013-07-01

    Full Text Available Polar regions refer to the areas at high latitudes and altitudes, that are characterized by low temperature and limited nutrients, and are very vulnerable and sensitive to global climate change. They include the Antarctic, the Arctic and the Tibetan Plateau, which is recognized as “the third pole”. The harsh polar environments are inhabited by abundant microbes that shape and maintain ecosystems by driving biogeochemical cycles. This article herein reviews microbial diversity in these polar terrestrial environments, including soils, lakes and glaciers in the Antarctic, the Arctic and the Tibetan Plateau. In the three poles, five major groups of microbes have been detected, e.g. Acidobacteria, Actinobacteria, Bacteroidetes, Cynobacteria, and Firmicutes. These microbes are salt- and cold-tolerant. Research in polar microbial ecology in China is currently lagging behind developed countries. Priorities should be given to long-term observations on theTibetan Plateau, which is easily approached. This will facilitate microbial ecology research and expand our understanding of microbial processes and their ecological roles in extreme environments.

  20. Comparing Perception-Based and Geographic Information System (GIS)-based characterizations of the local food environment.

    Science.gov (United States)

    Moore, Latetia V; Diez Roux, Ana V; Brines, Shannon

    2008-03-01

    Measuring features of the local food environment has been a major challenge in studying the effect of the environment on diet. This study examined associations between alternate ways of characterizing the local food environment by comparing Geographic Information System (GIS)-derived densities of various types of stores to perception-based measures of the availability of healthy foods. Survey questions rating the availability of produce and low-fat products in neighborhoods were aggregated into a healthy food availability score for 5,774 residents of North Carolina, Maryland, and New York. Densities of supermarkets and smaller stores per square mile were computed for 1 mile around each respondent's residence using kernel estimation. The number of different store types in the area was used to measure variety in the food environment. Linear regression was used to examine associations of store densities and variety with reported availability. Respondents living in areas with lower densities of supermarkets rated the selection and availability of produce and low-fat foods 17% lower than those in areas with the highest densities of supermarkets (95% CL, -18.8, -15.1). In areas without supermarkets, low densities of smaller stores and less store variety were associated with worse perceived availability of healthy foods only in North Carolina (8.8% lower availability, 95% CL, -13.8, -3.4 for lowest vs. highest small-store density; 10.5% lower 95% CL, -16.0, -4.7 for least vs. most store variety). In contrast, higher smaller store densities and more variety were associated with worse perceived healthy food availability in Maryland. Perception- and GIS-based characterizations of the environment are associated but are not identical. Combinations of different types of measures may yield more valid measures of the environment.

  1. Compressive Tectonics around Tibetan Plateau Edges

    Institute of Scientific and Technical Information of China (English)

    Zhao Zhixin; Xu Jiren

    2009-01-01

    Various earthquake fault types, mechanism solutions, stress field, and other geophysical data were analyzed for study on the crust movement in the Tibetan plateau and its tectonic implications. The results show that numbers of thrust fault and strike-slip fault type earthquakes with strong compressive stress near NNE-SSW direction occurred in the edges around the plateau except the eastern boundary. Some normal faulting type earthquakes concentrate in the Central Tibetan plateau. The strikes of fault planes of thrust and strike-slip faulting earthquakes are almost in the E-W direction based on the analyses of the Wulff stereonet diagrams of fault plane solutions. This implies that the dislocation slip vectors of the thrust and strike-slip faulting type events have quite great components in the N-S direction. The compression motion mainly probably plays the tectonic active regime around the plateau edges. The compressive stress in N-S or NE-SW directions predominates earthquake occurrence in the thrust and strike-slip faulting event region around the plateau. The compressive motion around the Tibetan plateau edge is attributable to the northward motion of the Indian subcontinent plate. The northward motion of the Tibetan plateau shortened in the N-S direction encounters probably strong obstructions at the western and northern margins.

  2. Characterization of energy flux partitioning in urban environments: links with surface seasonal properties

    OpenAIRE

    Loridan, Thomas; C. S. B. Grimmond

    2012-01-01

    A better understanding of links between the properties of the urban environment and the exchange to the atmosphere is central to a wide range of applications. The numerous measurements of surface energy balance data in urban areas enable intercomparison of observed fluxes from distinct environments. This study analyzes a large database in two new ways. First, instead of normalizing fluxes using net all-wave radiation only the incoming radiative fluxes are used, to remove the surface attribute...

  3. Reduced quantum dynamics with initial system-environment correlations characterized by pure Markov states

    Science.gov (United States)

    Türkmen, A.; Verçin, A.; Yılmaz, S.

    2016-09-01

    Any tripartite state which saturates the strong subadditivity relation for the quantum entropy is defined as the Markov state. A tripartite pure state describing an open system, its environment, and their purifying system is a pure Markov state if and only if the bipartite marginal state of the purifying system and environment is a product state. It has been shown that as long as the purification of the input system-environment state is a pure Markov state, the reduced dynamics of the open system can be described, on the support of the initial system state, by a quantum channel for every joint unitary evolution of the system-environment composite even in the presence of initial correlations. Entanglement, discord, and classical correlations of the initial system-environment states implied by the pure Markov states are analyzed and it has been shown that all these correlations are entirely specified by the entropy of environment. Some implications concerning perfect quantum error correction procedure and quantum Markovian dynamics are presented.

  4. 高原地区高压共轨柴油机掺烧生物柴油的性能研究%A Research on the Performance of a Common Rail Diesel Engine Fueled with Bio-diesels under Plateau Environment

    Institute of Scientific and Technical Information of China (English)

    刘阳阳; 谭泽飞

    2012-01-01

    The performance of Common Rail Diesel engine fueled with diesel fuel (DO) and different blending ratio of Bio-diesels ((B10,R20,B30,B50) under Plateau Environment (81 kpa, tests comparatively the characteristics like engine power, economy and smoke is discused. The results show that the engine fueled with different blending ratio of Bio-diesels has higher brake specific fuel consumption in comparison with BO fueled engine, but it has lower power and lower smoke. But with the increase in bio-diesel blending ratio, engine power and smoker drops, fuel consumption increases.%研究了在高原地区(81 kPa)掺烧不同比例生物柴油(B10,B20,B30,B50)在高压共轨柴油机上的性能.对发动机的动力性、经济性、烟度进行对比试验.结果表明:燃用一定比例的生物柴油发动机实测油耗增加,并且随生物柴油掺烧比例增加而增加;动力性和碳烟排放降低,并且随着生物柴油掺烧比例的增加逐渐降低.

  5. Study on the relevance of some of the description methods for plateau-honed surfaces

    Science.gov (United States)

    Yousfi, M.; Mezghani, S.; Demirci, I.; El Mansori, M.

    2014-01-01

    Much work has been undertaken in recent years into the determination of a complete parametric description of plateau-honed surfaces with the intention of making a link between the process conditions, the surface topography and the required functional performances. Different advanced techniques (plateau/valleys decomposition using the normalized Abbott-Firestone curve or morphological operators, multiscale decomposition using continuous wavelets transform, etc) were proposed and applied in different studies. This paper re-examines the current state of developments and addresses a discussion on the relevance of the different proposed parameters and characterization methods for plateau-honed surfaces by considering the control loop manufacturing-characterization-function. The relevance of appropriate characterization is demonstrated through two experimental studies. They consider the effect of the most plateau honing process variables (the abrasive grit size and abrasive indentation velocity in finish-honing and the plateau-honing stage duration and pressure) on cylinder liner surface textures and hydrodynamic friction of the ring-pack system.

  6. Dendroclimatic reconstructions for the southern Colorado plateau

    Energy Technology Data Exchange (ETDEWEB)

    Dean, J.S.; Funkhouser, G.S. [Univ. of Arizona, Tucson, AZ (United States)

    1995-09-01

    A geographical network of climate sensitive tree-ring chronologies consisting of 25 archaeological sequences and two bristlecone pine series provides the basis for high resolution reconstructions of low and high frequency climatic variability on the southern Colorado Plateau over the last 1,500 years. Qualitative and quantitative dendroclimatic analyses of these data produce annual retrodictions of yearly and seasonal precipitation and summer Palmer Drought Severity Indices for each station and reconstructions of regional scale patterns in climatic variability. These reconstructions provide detailed information on climatic fluctuations that affected biotic and human populations as well as long-term baseline data for evaluating present-day climate and estimating future climatic trends. When integrated with other measures of past environmental variability, these reconstructions specify periods of favorable and unfavorable environmental conditions that would have affected past human populations of the region. The severest degradation, which occurred between A.D. 1250 and 1450, probably was causally related to numerous cultural changes that occurred at the end of the l3th century including the Anasazi abandonment of the Four Comers area. Projecting environmental patterns that characterized the last two millennia into the future indicates potential hazards to long term uranium mill waste disposal and containment and the potential and limitations of environmental restoration.

  7. 论草地建设在黄土高原地区 生态环境建设中的战略地位%Discoursing strategic role of grassland construction in construction of ecological environments for Loess Plateau region

    Institute of Scientific and Technical Information of China (English)

    朱士光

    2001-01-01

    At present, the vegetation is sparse and the ecolog ical environment is also deteriorating on Loess Plateau Region. In historical pe riod, prairie took up a larger part of the natural vegetation area and the destr oyment resulted from human′s activities is mostly distinguished. After many-ye ars practice, however, a series of suitable grass types are easier to survive t h an planting trees in hillocks and hills, where the ecological environments are b ecoming quite harsh. On Loess Plateau region, moreover,these grass types can e ffectively improve ecological environments and the local conditions of planting trees. In addition, man can also attain return easily in the aspect of econo my. Therefore, during the systematic project of implementing the strategy of Gre en Defence, recreating ecological environments with elegant mountain and river, t he way of planting grass by man plays so important a strategic role as fighting in the van and forming base. By taking up such strategy as strengthening propaga nda and education, drawing up work plan, managing carefully and strengthening t he study and instruction of science and technology, such a way can be populated and implemented on a large scale by the way of organization.%我国黄土高原地区当前植被稀疏,生态环境恶劣.由 于人类历史时期这一地区之天然植被中草原占有较大面积,所遭受的人为活动的破坏也最为 显著;加上经多年实践,一批适生草类在黄土高原地区生态环境变得十分严酷的山塬丘陵与 风沙滩地比造林易于成活,改善生态环境与造林立地条件之功用易于见效,在经济上也易于 获得回报,因而在这一地区实施绿色屏障方略、再造秀美山川之生态环境建设系统工程中, 人工种草实处于奠基础的重要战略地位.应通过采取加强宣传教育、制订工作规划、 认真管理、加强科学技术研究与指导等措施,大规模推行实施.

  8. Nanotribological characterization of human head hair by friction force microscopy in dry atmosphere and aqueous environment.

    Science.gov (United States)

    Nikogeorgos, Nikos; Fletcher, Ian W; Boardman, Christopher; Doyle, Peter; Ortuoste, Nerea; Leggett, Graham J

    2010-06-01

    Friction force microscopy was employed for the tribological investigation of human head hair in two different environments: a dry atmosphere and de-ionized water. The fibers were immobilized by embedding them in indium. The effects of bleaching, conditioning, and immersion in methanolic KOH were quantified in terms of the relative coefficient of friction (μ). The virgin fibers were clearly distinguished in terms of friction coefficient from the chemically damaged ones in both environments, while all categories of hair exhibited higher friction coefficients in the aqueous environment. Secondary ion mass spectroscopy was used as a complementary technique to examine the presence of fatty acids on the cuticular surface of the different categories of hair as well as the conditioner distribution. Neither bleaching nor 30 min treatment in methanolic KOH was found adequate to completely remove the fatty acids from the fibers' surface. Conditioner species were detected along the whole cuticular surface.

  9. Antipodal Linear Tapered Slot Antenna Based Radio Link Characterization in Narrow Hallway Environment at 60 GHz

    Science.gov (United States)

    Shrivastava, Purva; Rao, T. Rama

    2016-09-01

    The performance of wireless communication systems is predominantly dependent on propagation environment and respective radiating antennas. Due to the shorter wavelength at millimeter wave (MmW) frequencies, the propagation loss through the objects in indoor environments is typically very high. To improve the channel capacity and to reduce inter-user interference, a high gain directional antenna is desired at MmW frequencies. Traditional antennas used in MmW devices are not suitable for low-cost commercial devices due to their heavy and bulky configurations. This paper focuses on design and development of a very compact (44.61 × 9.93 × 0.381 mm) high gain antipodal linear tapered slot antenna (ALTSA) utilizing substrate integrated waveguide (SIW) technology at 60 GHz. Received signal strength (RSS), path loss, and capacity are studied for MmW indoor applications utilizing ALTSA with radio frequency (RF) measurement equipment in narrow hallway environment.

  10. Detection and characterization of Salmonella spp. in recreational aquatic environments in the Northeast of Argentina

    Directory of Open Access Journals (Sweden)

    María Fernanda Tracogna

    2013-08-01

    Full Text Available The aim of this work was to detect the presence of Salmonella spp. in recreational aquatic environments in the Northeast of Argentina and to relate it with water and environmental parameters. Sixty eight samples of water from recreational aquatic environments in the provinces of Chaco and Corrientes, Argentina, were studied. Salmonellae were detected in 6 samples (8.8%. Salmonella spp. isolates belonged to the following species and serovars: S. enterica serovar Give, S. enterica subespecie IV, S. enterica ser. Bredeney, S. enterica ser. Rubislaw, and S. enterica ser. Enteritidis (two isolates. None of the isolates were resistant to tested antimicrobials. There were no significant differences among sampling sites as a reservoir of bacteria Salmonella spp. and the other variables. The presence of Salmonella spp. in our recreational aquatic environments reaffirms the need for monitoring in order to minimize the risks of infection to exposed persons.

  11. Constructions of new plateaued functions from known ones

    Institute of Scientific and Technical Information of China (English)

    Zhang Weiguo; Ding Yong; Zhang Ning; Xiao Guozhen

    2008-01-01

    A number of methods for constructing new plateaued functions from known ones are presented. By properly combining the known plateaued functions it is possible to get highly nonlinear resilient plateaued functions. The order, resiliency and propagation characteristics of the constructed plateaued functions are discussed. We show the new functions could possess the desirable cryptographic property.

  12. Characteristics of land-atmosphere energy and turbulentfluxes over the plateau steppe in central Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    The land-atmosphere energy and turbulence exchange is key to understanding land surface processes on the TibetanPlateau (TP). Using observed data for Aug. 4 to Dec. 3, 2012 from the Bujiao observation point (BJ) of the Nagqu PlateauClimate and Environment Station (NPCE-BJ), different characteristics of the energy flux during the Asian summermonsoon (ASM) season and post-monsoon period were analyzed. This study outlines the impact of the ASM on energyfluxes in the central TP. It also demonstrates that the surface energy closure rate during the ASM season is higher than thatof the post-monsoon period. Footprint modeling shows the distribution of data quality assessments (QA) and qualitycontrols (QC) surrounding the observation point. The measured turbulent flux data at the NPCE-BJ site were highly representativeof the target land-use type. The target surface contributed more to the fluxes under unstable conditions thanunder stable conditions. The main wind directions (180° and 210°) with the highest data density showed flux contributionsreaching 100%, even under stable conditions. The lowest flux contributions were found in sectors with low data density,e.g., 90.4% in the 360° sector under stable conditions during the ASM season. Lastly, a surface energy water balance(SEWAB) model was used to gap-fill any absent or corrected turbulence data. The potential simulation error was alsoexplored in this study. The Nash-Sutcliffe model efficiency coefficients (NSEs) of the observed fluxes with the SEWABmodel runs were 0.78 for sensible heat flux and 0.63 for latent heat flux during the ASM season, but unrealistic values of?0.9 for latent heat flux during the post-monsoon period.

  13. Characterization of the Space Environment on Orbit of the International Space Station

    Science.gov (United States)

    Yamagata, Ichiro

    The material-exposure experiment was performed on the International Space Station using the Micro-Particles Capturer and Space Environment Exposure Device (MPAC & SEED) developed by the Japan Aerospace Exploration Agency. The experiment was executed on the exterior of the Russian Service Module (SM) of the International Space Station. The SM/MPAC & SEED consists of the MPAC, which captures the space debris, and the SEED, which exposes the polymeric material, the paints, the adhesive, the bearing, and the compound material. This paper is focused on space dust environment, and the results of the MPAC experiment are described.

  14. Characterizing the role of built environment stocks in human development and emission growth

    DEFF Research Database (Denmark)

    Lin, Chen; Liu, Gang; Müller, Daniel B.

    2017-01-01

    The built environment stocks such as buildings and infrastructures are key to human development: they provide the fundamental physical settings that the provision of basic human needs such as food, shelter, and transport rely on, but also contribute to anthropogenic greenhouse gas (GHG) emissions...... throughout their construction, operation, and end-of-life management phases. These stocks usually exist in societies for relatively long time, from years to over a century, therefore their dynamics have long term impacts on human development and emission growth. Several recent studies, including the Fifth...... underline the role of built environment stocks in human development, future emission pathways, and relevant climate policy....

  15. Argalis on the Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The argali are listed by the State as animals subject tosecond-class protection,and no killing is allowed. The international communitylists argali on the Qinghai-Tibet Plateau as animals that must not be hunted.

  16. Colorado Plateau Rapid Ecoregion Assessment Data Catalog

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — Datasets used in the analysis of the Colorado Plateau (COP) Rapid Ecoregion Assessment (REA).They can be downloaded via a layer package (lpk, similar to a zip file...

  17. The application of magnetic measurements for the characterization of atmospheric particulate pollution within the airport environment.

    Science.gov (United States)

    Jones, S; Richardson, N; Bennett, M; Hoon, S R

    2015-01-01

    The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of atmospheric particulate matter (PM) on health and the environment. PM within the airport environment may be derived from a range of sources. To date, however, the identification of individual sources of airport derived PM has remained elusive but constitutes a research priority for the aviation industry.The aim of this research was to identify distinctive and characteristic fingerprints of atmospheric PM derived from various sources in an airport environment through the use of environmental magnetic measurements. PM samples from aircraft engine emissions, brake wear and tire wear residues have been obtained from a range of different aircraft and engine types. Samples have been analyzed utilizing a range of magnetic mineral properties indicative of magnetic mineralogy and grain size. Results indicate that the dusts from the three 'aircraft' sources, (i.e. engines, brakes and tires) display distinctive magnetic mineral characteristics which may serve as 'magnetic fingerprints' for these sources. Magnetic measurements of runway dusts collected at different locations on the runway surface also show contrasting magnetic characteristics which, when compared with those of the aircraft-derived samples, suggest that they may relate to different sources characteristic of aircraft emissions at various stages of the take-off/landing cycle. The findings suggest that magnetic measurements could have wider applicability for the differentiation and identification of PM within the airport environment.

  18. Characterizing Pedagogical Practices of University Physics Students in Informal Learning Environments

    Science.gov (United States)

    Hinko, Kathleen A.; Madigan, Peter; Miller, Eric; Finkelstein, Noah D.

    2016-01-01

    University educators (UEs) have a long history of teaching physics not only in formal classroom settings but also in informal outreach environments. The pedagogical practices of UEs in informal physics teaching have not been widely studied, and they may provide insight into formal practices and preparation. We investigate the interactions between…

  19. Fading characterization for context aware body area networks (CABAN) in interactive smart environments

    NARCIS (Netherlands)

    Heaney, S.F.; Scanlon, W.G.; Garcia-Palacios, E.; Cotton, S.L.

    2010-01-01

    Body Area Networks are unique in that the large-scale mobility of users allows the network itself to travel across a diverse range of operating domains. This presents the possibility of creating interactive smart environments where Context Aware Body Area Networks can sense and co-operate with nearb

  20. Pyramid Schemes on the Tibetan Plateau

    OpenAIRE

    Devin Gonier; Rgyal yum sgrol ma

    2012-01-01

    The unique features of pyramid schemes and certain underlying causes for their development on the Tibetan Plateau are analyzed. Research was conducted by analyzing 521 surveys, allowing estimation of pyramid scheme activity on the Plateau and an identification of related cultural and social specificities. Firsthand accounts were collected revealing details of personal involvement. Survey data and similarities in the accounts were studied to suggest how involvement in pyramid schemes might be ...

  1. Characterization and modeling of on-body spatial diversity within indoor environments at 868 MHz

    NARCIS (Netherlands)

    Cotton, S.L.; Scanlon, W.G.

    2009-01-01

    For the first time in the open literature we present a full characterization of the performance of receiver diversity for the on-body channels found in body area networks. The study involved three commonly encountered diversity combining schemes: selection combination (SC), maximal ratio combining (

  2. Characterizing the galaxy populations within different environments in the RCS2319 supercluster

    Science.gov (United States)

    Delahaye, Anna; Webb, Tracy

    We present the results of a multi-wavelength photometric study of the high redshift supercluster RCS2319+00. RCS2319+00 is a high-redshift (z ~ 0.9) supercluster comprising three spectroscopically confrmed cluster cores discovered in the Red Sequence Cluster Survey (RCS) (Gladders & Yee 2005). Core proximities and merger rates estimate coalescence into a 1015 M ⊙ cluster by z ~ 0.5 (Gilbank et al. 2008). Spectroscopic studies of the system have revealed over 300 supercluster members located in the cores and several infalling groups (Faloon et al. 2013). RCS2319 presents a diverse range of dynamical systems and densities making it an ideal laboratory in which to study the effects of environment on galaxy properties. Imaging in optical and near infrared (griz' from MegaCam, JK s from WIRCam, both at CFHT), as well as 3.6 μm and 4.5μm from IRAC have enabled the assembly of a large photometric catalogue. Coupled with an extensive spectroscopic survey (Faloon et al. 2013) providing nearly 2400 redshifts across the field, photometric redshifts were determined using the template fitting code EAZY (Brammer et al. 2008). Nearly 80 000 photometric redshifts were measured providing a sample of nearly 3000 cluster members. To investigate effects of global environment, analysis was done utilizing a friend-of-friends group finding algorithm identifying several large and small infalling groups along with the three cluster cores. The cores are found to be dominated by massive, red galaxies and the field galaxies are populated by low mass, blue galaxies, as is the case in the local universe. Interestingly, the large groups exhibit intermediate properties between field and core populations, suggesting possible pre-processing as they are being accreted into the core halos. Relative fifth-nearest neighbour overdensity, log(1+δ5), is used as a proxy for local environment to investigate environmental dependence on galaxy colour. While there is an overall dependence of colour on

  3. Health risk characterization for exposure to benzene in service stations and petroleum refineries environments using human adverse response data

    Directory of Open Access Journals (Sweden)

    Benjamin Edokpolo

    2015-01-01

    Full Text Available Health risk characterization of exposure to benzene in service stations and petroleum refineries has been carried out in previous studies using guideline values set by various agencies. In this work, health risk was characterized with the exposure data as cumulative probability distribution (CPD plots but using human epidemiological data. This was achieved by using lowest observable adverse effects levels (LOAEL data plotted as cumulative probability lowest effects distribution (CPLED. The health risk due to benzene was characterized by using probabilistic methods of hazard quotient (HQ50/50 and HQ95/5, Monte-Carlo simulation (MCS and overall risk probability (ORP. CPD relationships of adverse health effects relationships and exposure data were in terms of average daily dose (ADD and lifetime average daily dose (LADD for benzene. For service station environments HQ50/50 and HQ95/5 were in a range of 0.000071–0.055 and 0.0049–21, respectively. On the other hand, the risk estimated for petroleum refinery environments suggests higher risk with HQ50/50 and HQ95/5 values ranging from 0.0012 to 77 and 0.17 to 560, respectively. The results of Monte-Carlo risk probability (MRP and ORP indicated that workers in petroleum refineries (MRP of 2.9–56% and ORP of 4.6–52% of the affected population were at a higher risk of adverse health effects from exposure to benzene as compared to exposure to benzene in service station environments (MRP of 0.051 –3.4% and ORP of 0.35–2.7% affected population. The adverse effect risk probabilities estimated by using the Monte-Carlo simulation technique and the ORP method were found to be generally consistent.

  4. Spectral characterization of environment-sensitive adducts of interleukin-1 beta.

    Science.gov (United States)

    Epps, D E; Yem, A W; Fisher, J F; McGee, J E; Paslay, J W; Deibel, M R

    1992-02-15

    We have determined the fluorescence properties of two covalently attached acrylodan derivatives of recombinant human interleukin-1 beta, namely the Cys-8 and Lys-103 adducts. The emission and excitation maxima indicated the presence of two operationally distinct conformers for each probe. The iodide quenching and the kinetics of fluorescence changes associated with guanidinium chloride-induced denaturation show that each covalent adduct exists both in hydrated and dehydrated environments. Furthermore, fluorescence changes associated with the binding of the adducts to a recombinant soluble murine receptor indicated that only the conformers with the label in the hydrophobic environment are competent toward the soluble murine interleukin receptor and that the hydrated and dehydrated conformers are in a dynamic equilibrium on the time scale of the binding experiments.

  5. Polyphasic characterization of heterotrophic bacteria from shrimp farm environments to tetracyclines

    OpenAIRE

    Rafael dos Santos Rocha

    2016-01-01

    Antimicrobial agents of tetracycline class has been extensively used in aquaculture for disease control and growth promotion. Thus, the aim of this study was to evaluate the polyphase profile of the bacterial community in shrimp farming environment front antimicrobial classes of tetracyclines, focusing on Vibrio genus. Water and sediment samples were collected four (4) shrimp farms: two (2) in the state of Cearà and two (2) in the state of Rio Grande do Norte, of points: estuary, supply chann...

  6. Phenotypic characterization of Salmonella isolated from food production environments associated with low-water activity foods.

    Science.gov (United States)

    Finn, Sarah; Hinton, Jay C D; McClure, Peter; Amézquita, Aléjandro; Martins, Marta; Fanning, Séamus

    2013-09-01

    Salmonella can survive for extended periods of time in low-moisture environments posing a challenge for modern food production. This dangerous pathogen must be controlled throughout the production chain with a minimal risk of dissemination. Limited information is currently available describing the behavior and characteristics of this important zoonotic foodborne bacterium in low-moisture food production environments and in food. In our study, the phenotypes related to low-moisture survival of 46 Salmonella isolates were examined. Most of the isolates in the collection could form biofilms under defined laboratory conditions, with 57% being positive for curli fimbriae production and 75% of the collection positive for cellulose production, which are both linked with stronger biofilm formation. Biocides in the factory environment to manage hygiene were found to be most effective against planktonic cells but less so when the same bacteria were surface dried or present as a biofilm. Cellulose-producing isolates were better survivors when exposed to a biocide compared with cellulose-negative isolates. Examination of Salmonella growth of these 18 serotypes in NaCl, KCl, and glycerol found that glycerol was the least inhibitory of these three humectants. We identified a significant correlation between the ability to survive in glycerol and the ability to survive in KCl and biofilm formation, which may be important for food safety and the protection of public health.

  7. Characterization of Escherichia coli MG1655 grown in a low-shear modeled microgravity environment

    Directory of Open Access Journals (Sweden)

    Pierson Duane L

    2007-03-01

    Full Text Available Abstract Background Extra-cellular shear force is an important environmental parameter that is significant both medically and in the space environment. Escherichia coli cells grown in a low-shear modeled microgravity (LSMMG environment produced in a high aspect rotating vessel (HARV were subjected to transcriptional and physiological analysis. Results Aerobic LSMMG cultures were grown in rich (LB and minimal (MOPS + glucose medium with a normal gravity vector HARV control. Reproducible changes in transcription were seen, but no specific LSMMG responsive genes were identified. Instead, absence of shear and a randomized gravity vector appears to cause local extra-cellular environmental changes, which elicit reproducible cellular responses. In minimal media, the majority of the significantly up- or down-regulated genes of known function were associated with the cell envelope. In rich medium, most LSMMG down-regulated genes were involved in translation. No observable changes in post-culture stress responses and antibiotic sensitivity were seen in cells immediately after exposure to LSMMG. Comparison with earlier studies of Salmonella enterica serovar Typhimurium conducted under similar growth conditions, revealed essentially no similarity in the genes that were significantly up- or down-regulated. Conclusion Comparison of these results to previous studies suggests that different organisms may dramatically differ in their responses to medically significant low-shear and space environments. Depending on their specific response, some organisms, such as Salmonella, may become preadapted in a manner that predisposes them to increased virulence.

  8. Extraction and Characterization of Polyhydroxybutyrates (PHB from Bacillus thuringiensisKSADL127 Isolated from Mangrove Environments of Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abdullah A. Alarfaj

    2015-10-01

    Full Text Available ABSTRACTPolyhydroxybutyrate (PHB is a renowned biodegradable plastic that do not release any toxins or residues in the environment like petroleum based plastics. In the present study, 50 bacteria isolated from mangrove niche, Saudi Arabia, were screened for maximum PHB production. All the 50 strains showed positive for PHB production, of which one strain showed maximum of 137 mgL-1. The most PHB accumulated bacterium was selected and identified asBacillus thuringiensis KSADL127, based on phenotypic characterization and 16S rRNA sequence analysis. Characterization of extracted PHB was carried out by FT-IR, NMR, UV spectroscopy, DSC, TGA, and LC-MS, which later confirmed the presence of intracellular accumulated polymer and substantiated as PHB.

  9. Synthesis and Characterization of Divalent Manganese, Iron, and Cobalt Complexes in Tripodal Phenolate/N-Heterocyclic Carbene Ligand Environments

    DEFF Research Database (Denmark)

    Käß, Martina; Hohenberger, Johannes; Adelhardt, Mario

    2014-01-01

    . The complete ligand series offers a convenient way of tuning the electronic and steric environment around the metal center, thus, allowing for control of the complex’s reactivity. This series of divalent complexes of Mn, Fe, and Co was synthesized and characterized by 1H NMR, IR, and UV/vis spectroscopy....... Zero-field 57Fe Mössbauer spectroscopy of the Fe(II) complexes 3, 4, 8, and 11 shows isomer shifts δ that increase gradually as carbenes are substituted for phenolates in the series of ligands. From the single-crystal structure determinations of the complexes, the different steric demand...

  10. San Luis Valley - Taos Plateau Landscape-Level Cultural Heritage Values and Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wescott, Konstance L. [Argonne National Lab. (ANL), Argonne, IL (United States); Abplanalp, Jennifer M. [Argonne National Lab. (ANL), Argonne, IL (United States); Brown, Jeff [Bureau of Land Management, Monte Vista, CO (United States); Cantwell, Brian [Argonne National Lab. (ANL), Argonne, IL (United States); Dicks, Merrill [Bureau of Land Management, Taos, NM (United States); Fredericks, Brian [Bureau of Land Management, Monte Vista, CO (United States); Krall, Angie [US Forest Service, Creede, CO (United States); Rollins, Katherine E. [Argonne National Lab. (ANL), Argonne, IL (United States); Sullivan, Robert [Argonne National Lab. (ANL), Argonne, IL (United States); Valdez, Arnie [Univ. of New Mexico, Albuquerque, NM (United States); Verhaaren, Bruce [Argonne National Lab. (ANL), Argonne, IL (United States); Vieira, Joseph [Bureau of Land Management, Monte Vista, CO (United States); Walston, Lee [Argonne National Lab. (ANL), Argonne, IL (United States); Zvolanek, Emily A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-01

    The San Luis Valley – Taos Plateau Landscape-Level Cultural Heritage Values and Risk Assessment (hereafter referred to as cultural assessment) is a BLM pilot project designed to see whether the Rapid Ecoregional Assessment (REA) framework (already established and implemented throughout many ecoregions in the West) can be applied to the cultural environment.

  11. Characterization of absorbing aerosol types using ground and satellites based observations over an urban environment

    Science.gov (United States)

    Bibi, Samina; Alam, Khan; Chishtie, Farrukh; Bibi, Humera

    2017-02-01

    In this paper, for the first time, an effort has been made to seasonally characterize the absorbing aerosols into different types using ground and satellite based observations. For this purpose, optical properties of aerosol retrieved from AErosol RObotic NETwork (AERONET) and Ozone Monitoring Instrument (OMI) were utilized over Karachi for the period 2012 to 2014. Firstly, OMI AODabs was validated with AERONET AODabs and found to have a high degree of correlation. Then, based on this validation, characterization was conducted by analyzing aerosol Fine Mode Fraction (FMF), Angstrom Exponent (AE), Absorption Angstrom Exponent (AAE), Single Scattering Albedo (SSA) and Aerosol Index (AI) and their mutual correlation, to identify the absorbing aerosol types and also to examine the variability in seasonal distribution. The absorbing aerosols were characterized into Mostly Black Carbon (BC), Mostly Dust and Mixed BC & Dust. The results revealed that Mostly BC aerosols contributed dominantly during winter and postmonsoon whereas, Mostly Dust were dominant during summer and premonsoon. These types of absorbing aerosol were also confirmed with MODerate resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) observations.

  12. Agulhas Plateau and Mozambique Ridge: Two LIPS of a Kind?

    Science.gov (United States)

    Uenzelmann-Neben, G.; Gohl, K.; Parsiegla, N.

    2008-12-01

    The seaway south of South Africa represents a critical gateway within the global ocean circulation. Here, warm surface and cold deep and bottom water masses meet and lead to a transfer of heat and salt between the Indian and Atlantic Oceans. This transfer maintains the global thermohaline circulation. The paths of the oceanic currents are strongly influenced by the seafloor topography observed in this region. Thus, the tectonic evolution of the South African continental margin and the gateway starting in Cretaceous times are of major importance in order to understand the evolution of the current system and the transition from the Greenhouse to the Icehouse world. The gateway itself is characterized by the Agulhas Plateau, which has been postulated to originate in the interaction of the Bouvet Hotspot and a triple junction and thus to fall within the world-wide suite of Large Igneous Provinces [Gohl and Uenzelmann-Neben, 2001; Parsiegla, et al., 2008; Uenzelmann-Neben, et al., 1999]. A similar structure has been identified for the crust of the southern Mozambique Ridge [Gohl, et al., submitted]. This raises the question whether those two LIP events were related, whether their emplacement happened at the same time and how they tie in with other LIP events observed in Late Cretaceous times such as the formation or the Kerguelen LIP. Furthermore, we may speculate on the effect those magmatic events had on the evolution of both oceanic currents and the climate. Similarities as well as differences in crustal structure and evolution and later sedimentary development will be presented for those two structures based on seismic refraction and reflection data. References: Gohl, K. and G. Uenzelmann-Neben (2001), The crustal role of the Agulhas Plateau, southwest Indian Ocean: Evidence from seismic profiling, Geophysical Journal International, 144, 632-646. Gohl, K., et al. (submitted), Is the Mozambique Ridge related to the Agulhas Plateau Large Igneous Province?, Geophysical

  13. Characterization and differentiation of rock varnish types from different environments by microanalytical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Macholdt, D. S. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Jochum, K. P. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Pöhlker, C. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Arangio, A. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Förster, J. -D. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Stoll, B. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Weis, U. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Weber, B. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Müller, M. [Max Planck Inst. for Polymer Research, Mainz (Germany); Kappl, M. [Max Planck Inst. for Polymer Research, Mainz (Germany); Shiraiwa, M. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Kilcoyne, A. L. D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weigand, M. [Max Planck Inst. for Intelligent Systems, Stuttgart (Germany); Scholz, D. [Johannes Gutenberg Univ., Mainz (Germany); Haug, G. H. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; Al-Amri, A. [King Saud Univ., Riyadh (Saudi Arabia); Andreae, M. O. [Max Planck Society, Mainz (Germany). Max Planck Inst. for Chemistry; King Saud Univ., Riyadh (Saudi Arabia)

    2017-04-13

    We investigated rock varnishes collected from several locations and environments worldwide by a wide range of microanalytical techniques. These techniques were selected to address the challenges posed by the chemical and structural complexity within the micrometer- to nanometer-sized structures in these geological materials. Femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fs LA-ICP-MS), scanning transmission X-ray microscopy-near edge X-ray adsorption fine structure spectroscopy (STXM-NEXAFS) in combination with scanning electron microscopy (SEM) of focused ion beam (FIB) ultra-thin (100–200 nm) sections, conventional and polarization microscopy, as well as electron paramagnetic resonance (EPR) measurements were used to obtain information about these rock varnishes. Rock varnishes from different environments, which cannot readily be distinguished based on their macroscopic appearance, differ significantly in their constituent elemental mass fractions, e.g., of Mn, Fe, Ni, Co, Ba, and Pb, and their rare earth element (REE) patterns. Structural characteristics such as the particle sizes of embedded dust grains, internal structures such as layers of Mn-, Fe-, and Ca -rich material, and structures such as cavities varied between varnishes from different environments and regions in the world. The EPR spectra were consistent with aged biogenic Mn oxides in all samples, but showed subtle differences between samples of different origin. Our observations allow us to separate rock varnishes into different types, with differences that might be indicators of distinct geneses. Five different types of rock varnish could be distinguished, Type I–V, of which only Type I might be used as potential paleoclimate archive. Each varnish type has specific characteristics in terms of their elemental composition, element distribution, and structures. The combination of element ratios (Mn/Ba, Al/Ni, Mn/REY, Mn/Ce, Mn/Pb, La N /Yb N , and Ce/Ce*), total REE

  14. Observation and characterization of mode splitting in microsphere resonators in aquatic environment

    CERN Document Server

    Woosung, Kim; Zhu, Jiangang; Yang, Lan

    2011-01-01

    Whispering gallery mode (WGM) optical resonators utilizing resonance shift (RS) and mode splitting (MS) techniques have emerged as highly sensitive platforms for label-free detection of nano-scale objects. RS method has been demonstrated in various resonators in air and liquid. MS in microsphere resonators has not been achieved in aqueous environment up to date, despite its demonstration in microtoroid resonators. Here, we demonstrate scatterer-induced MS of WGMs in microsphere resonators in water. We determine the size range of particles that induces MS in a microsphere in water as a function of resonator mode volume and quality factor. The results are confirmed by the experimental observations.

  15. Molecular cloning of ob gene in Schizopygopsis pylzovi and its mRNA expression responding to seasonal cold environment at Qinghai-Tibetan Plateau%黄河裸裂尻鱼肥胖基因克隆及其对青藏高原季节性冷环境的适应性表达

    Institute of Scientific and Technical Information of China (English)

    赵兰英; 祁得林; 晁燕; 李长忠; 谢保胜; 申志新; 王国杰; 王振刚; 李超; 拜彬强

    2012-01-01

    目的 克隆黄河裸裂尻鱼肥胖基因(obese gene,ob),分析编码蛋白leptin的序列特征,检测ob mRNA的组织特异性表达和不同环境温度下肝胰脏和白肌ob mRNA的相对表达水平,为探究黄河裸裂尻鱼在青藏高原季节性寒冷环境下的生态适应机制提供科学数据.方法 利用RT-PCT、5′-RACE和3′-RACE法获得ob基因全长cDNA序列.通过已知cDNA序列设计半定量RT-PCR和real-time PCR引物,进行表达研究.结果 黄河裸裂尻鱼ob基因序列全长为1 337 bp,其中开放阅读框(ORF)长513 bp,编码170个氨基酸.黄河裸裂尻鱼ob mRNA在心脏、肾脏、脂肪、肠、精巢、肝胰脏、鳃、脑和肌肉9个被检组织中均有表达,其中在心脏中表达最强,肌肉组织中表达最弱.栖息水域环境温度下降,将显著抑制黄河裸裂尻鱼肝胰脏和白肌ob mRNA的表达.结论 黄河裸裂尻鱼ob基因特殊的组织表达特征可能与其特定组织的能量代谢及其特殊的生物学功能有关.Leptin在黄河裸裂尻鱼能量代谢调节和季节性环境适应方面发挥着重要作用.%Objective In order to provide scientific data for understanding the adaptive mechanism of Schizopygopsis pylzovi to seasonal cold environment at Qinghai -Tibetan Plateau, the obese gene (ob) of Schizopygopsis pylzovi was cloned and its encoding protein leptin was analyzed . Then the expression pattern of the ob mRNA in tissues and the relative expression level of the ob mRNA in he patopancreas and white muscle of Schizopygopsis pylzovi from habitats of different tern -peratures were assessed. Methods The fulHength cDNA of ob gene was cloned by RT-PCT, 5'41ACE and 3'41ACE methods. The expression pattern and relative expression level were determined by RT -PCR and reaMime PCR. Results The fulHength cDNA of ob gene was 1 337 bp, including a 513 bp complete ORF encoding a 170 amino acid peptide. The ob gene was expressed in the nine examined organs , including heart, kidney

  16. Characterizing Economic and Social Properties of Trust and Reputation Systems in P2P Environment

    Institute of Scientific and Technical Information of China (English)

    Yu-Feng Wang; Yoshiaki Hori; Kouichi Sakurai

    2008-01-01

    Considering the fact that P2P (Peer-to-Peer) systems are self-organized and autonomous, social-control mechanism (like trust and reputation) is essential to evaluate the trustworthiness of participating peers and to combat the selfish, dishonest and malicious peer behaviors. So, naturally, we advocate that P2P systems that gradually act as an important information infrastructure should be multi-disciplinary research topic, and reflect certain features of our society. So, from economic and social perspective, this paper designs the incentive-compatible reputation feedback scheme based on well-known economic model, and characterizes the social features of trust network in terms of efficiency and cost. Specifically, our framework has two distinctive purposes: first, from high-level perspective, we argue trust system is a special kind of social network, and an accurate characterization of the structural properties of the network can be of fundamental importance to understand the dynamics of the system. Thus, inspired by the concept of weighted small-world, this paper proposes new measurements to characterize the social properties of trust system, that is, highg lobal and local efficiency, and low cost; then, from relative low-level perspective, we argue that reputation feedback is a special kind of information, and it is not free. So, based on economic model, VCG (Vickrey-Clarke-Grove)-like reputation remuneration mechanism is proposed to stimulate rational peers not only to provide reputation feedback, but truthfully offer feedback. Furthermore, considering that trust and reputation is subjective, we classify the trust into functional trust and referral trust, and extend the referral trust to include two factors: similarity and truthfulness, which can efficiently reduce the trust inference error. The preliminary simulation results show the benefits of our proposal and the emergence of certain social properties in trust network.

  17. Geological Environments of the Late Cenozoic Lakes and Salt-forming and Oil-gas Pool-forming Actions in the Tibetan Plateau%青藏高原晚新生代湖泊地质环境与成盐成藏作用

    Institute of Scientific and Technical Information of China (English)

    郑绵平; 张雪飞; 侯献华; 王海雷; 李洪普; 施林峰

    2013-01-01

    geological and climatic history of the Tibetan Plateau from these sedimentary cores. Through comparing the chronologic results with the latest international standard, a more precise model of magnetostratigraphy was established. Based on studying the cold, warm and eurythermal saline minerals in Qaidam basin, the authors found 31 series of cold events since 2 Ma BP. From that time Qaidam basin began to intermittently appear cold events. The time of cold events is close to the chronologic data of Cenozic Global Glaciation. The uplift of the Tibetan Plateau was tentatively divided into several stages according to the study of the deposition rate and the particle size. At the first time, the authors found that there was a demarcation line in the middle of Qaidam basin, which was not only the boundary of paleo-atmospheric circulations but also the boundary of salt formation. The westerly wind inclined area located to the north of the investigated line reflects salt deposits in the cold-wet climate period. To the west of the study area, the cold saline sediments occurred after 2 Ma, whereas they gradually crystallized into cold saline deposits at 0.72 Ma;in contrast, the saline sedimentary period started at 0.048 Ma in the south part of the boundary. The point of view is put forward in this paper that potassium was concentrated by the transportation of the multi-stage salt basin lying in the high mountain-deep basin environment, and this viewpoint can further improve the theory of potassium formation in continental facies. A new potash-rich brine horizon was found by the authors in the western Qaidam basin.

  18. Characterization and transferability of class 1 integrons in commensal bacteria isolated from farm and nonfarm environments.

    Science.gov (United States)

    Yang, Hua; Byelashov, Oleksandr A; Geornaras, Ifigenia; Goodridge, Lawrence D; Nightingale, Kendra K; Belk, Keith E; Smith, Gary C; Sofos, John N

    2010-12-01

    This study assessed the distribution of class 1 integrons in commensal bacteria isolated from agricultural and nonfarm environments, and the transferability of class 1 integrons to pathogenic bacteria. A total of 26 class 1 integron-positive isolates were detected in fecal samples from cattle operations and a city park, water samples from a beef ranch and city lakes, and soil, feed (unused), manure, and compost samples from a dairy farm. Antimicrobial susceptibility testing of class 1 integron-positive Enterobacteriaceae isolates from city locations displayed multi-resistance to 12-13 out of the 22 antibiotics tested, whereas class 1 integron-positive Enterobacteriaceae isolates from cattle operations only displayed tetracycline resistance. Most class 1 integrons had one gene cassette belonging to the aadA family that confers resistance to streptomycin and spectinomycin. One isolate from a dog fecal sample collected from a city dog park transferred its class 1 integron to a strain of Escherichia coli O157:H7 at a frequency of 10(-7) transconjugants/donor by in vitro filter mating experiments under the stated laboratory conditions. Due to the numerous factors that may affect the transferability testing, further investigation using different methodologies may be helpful to reveal the transferability of the integrons from other isolates. The presence of class 1 integrons among diverse commensal bacteria from agricultural and nonfarm environments strengthens the possible role of environmental commensals in serving as reservoirs of antibiotic resistance genes.

  19. Experimental Characterization of a Composite Morphing Radiator Prototype in a Relevant Thermal Environment

    Science.gov (United States)

    Bertagne, Christopher L.; Chong, Jorge B.; Whitcomb, John D.; Hartl, Darren J.; Erickson, Lisa R.

    2017-01-01

    For future long duration space missions, crewed vehicles will require advanced thermal control systems to maintain a desired internal environment temperature in spite of a large range of internal and external heat loads. Current radiators are only able to achieve turndown ratios (i.e. the ratio between the radiator's maximum and minimum heat rejection rates) of approximately 3:1. Upcoming missions will require radiators capable of 12:1 turndown ratios. A radiator with the ability to alter shape could significantly increase turndown capacity. Shape memory alloys (SMAs) offer promising qualities for this endeavor, namely their temperature-dependent phase change and capacity for work. In 2015, the first ever morphing radiator prototype was constructed in which SMA actuators passively altered the radiator shape in response to a thermal load. This work describes a follow-on endeavor to demonstrate a similar concept using highly thermally conductive composite materials. Numerous versions of this new concept were tested in a thermal vacuum environment and successfully demonstrated morphing behavior and variable heat rejection, achieving a turndown ratio of 4.84:1. A summary of these thermal experiments and their results are provided herein.

  20. Hydrotalcite Intercalated siRNA: Computational Characterization of the Interlayer Environment

    Directory of Open Access Journals (Sweden)

    Sean C. Smith

    2012-06-01

    Full Text Available Using molecular dynamics (MD simulations, we explore the structural and dynamical properties of siRNA within the intercalated environment of a Mg:Al 2:1 Layered Double Hydroxide (LDH nanoparticle. An ab initio force field (Condensed-phase Optimized Molecular Potentials for Atomistic Simulation Studies: COMPASS is used for the MD simulations of the hybrid organic-inorganic systems. The structure, arrangement, mobility, close contacts and hydrogen bonds associated with the intercalated RNA are examined and contrasted with those of the isolated RNA. Computed powder X-ray diffraction patterns are also compared with related LDH-DNA experiments. As a method of probing whether the intercalated environment approximates the crystalline or rather the aqueous state, we explore the stability of the principle parameters (e.g., the major groove width that differentiate both A- and A'- crystalline forms of siRNA and contrast this with recent findings for the same siRNA simulated in water. We find the crystalline forms remain structurally distinct when intercalated, whereas this is not the case in water. Implications for the stability of hybrid LDH-RNA systems are discussed.

  1. Index for characterizing post-fire soil environments in temperate coniferous forests

    Science.gov (United States)

    Jain, Theresa B.; Pilliod, David S.; Graham, Russell T.; Lentile, Leigh B.; Sandquist, Jonathan E.

    2012-01-01

    Many scientists and managers have an interest in describing the environment following a fire to understand the effects on soil productivity, vegetation growth, and wildlife habitat, but little research has focused on the scientific rationale for classifying the post-fire environment. We developed an empirically-grounded soil post-fire index (PFI) based on available science and ecological thresholds. Using over 50 literature sources, we identified a minimum of five broad categories of post-fire outcomes: (a) unburned, (b) abundant surface organic matter ( > 85% surface organic matter), (c) moderate amount of surface organic matter ( ≥ 40 through 85%), (d) small amounts of surface organic matter ( < 40%), and (e) absence of surface organic matter (no organic matter left). We then subdivided each broad category on the basis of post-fire mineral soil colors providing a more fine-tuned post-fire soil index. We related each PFI category to characteristics such as soil temperature and duration of heating during fire, and physical, chemical, and biological responses. Classifying or describing post-fire soil conditions consistently will improve interpretations of fire effects research and facilitate communication of potential responses or outcomes (e.g., erosion potential) from fires of varying severities.

  2. Synthesis and characterization of boehmites obtained from gibbsite in presence of different environments

    Energy Technology Data Exchange (ETDEWEB)

    Denigres Filho, Ricardo Wilson Nastari; Rocha, Gisele de Araujo; Vieira-Coelho, Antonio Carlos, E-mail: acvcoelh@usp.br [Universidade de Sao Paulo (LPSS/EP/USP), SP (Brazil). Departamento de Engenharia Metalurgica e de Materiais. Laboratorio de Materias-Primas Particuladas; Montes, Celia Regina [Centro de Energia Nuclear na Agricultura (NUPEGEL/CENA/USP), Piracicaba, SP (Brazil). Nucleo de Pesquisas Geoquimicas e Geofisicas da Listosfera

    2016-05-15

    In this study, results related to boehmite synthesis by hydrothermal processes starting from a Bayer commercial gibbsite are reported. The processes have been conducted from aqueous suspensions with initial acidic or alkaline pH, without or with acetate ion, at 160 deg C for 72h to 168h. The final materials were characterized by X-ray diffraction (XRD), thermal methods (DTA and TGA) and scanning electron microscopy (SEM). The influence of the synthesis conditions on the morphology of the boehmite crystals obtained from the gibbsite at different hydrothermal processes are discussed. (author)

  3. A trade-off analysis of policy objectives for Ansai, the Loess Plateau of China

    NARCIS (Netherlands)

    Lu, C.H.; Ittersum, van M.K.

    2004-01-01

    Ansai is a county characterized by hilly loess relief that experiences all problems typical to the Loess Plateau of northern China, such as population pressure, soil loss, over-use of marginal lands, and poverty and food insecurity problems. Alleviation of these problems needs an integrated consider

  4. On the relationship between environmental aridization of the Loess Plateau and soil water in loess

    Institute of Scientific and Technical Information of China (English)

    杨文治; 邵明安; 彭新德; 夏卫生

    1999-01-01

    The similarity between loess palaeo-environment and geographic distribution of modern bioclimatic zones is taken as a starting point; the relationship between the environmental aridization and soil water in loess is discussed from the point view of the soil water energy status and their soil water physical characteristics of modern loessial soils on the Loess Plateau. The soil water content becomes less and less from southeast to northwest, which not only provides favorable conditions for dust production by wind of loess origin, but also reveals that there is obviously a directional change in the environmental drought intensity of the Loess Plateau.

  5. 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...

  6. Characterization of photocatalytic TiO2 powder under varied environments using near ambient pressure X-ray photoelectron spectroscopy

    Science.gov (United States)

    Krishnan, Padmaja; Liu, Minghui; Itty, Pierre A.; Liu, Zhi; Rheinheimer, Vanessa; Zhang, Min-Hong; Monteiro, Paulo J. M.; Yu, Liya E.

    2017-01-01

    Consecutive eight study phases under the successive presence and absence of UV irradiation, water vapor, and oxygen were conducted to characterize surface changes in the photocatalytic TiO2 powder using near-ambient-pressure X-ray photoelectron spectroscopy (XPS). Both Ti 2p and O 1s spectra show hysteresis through the experimental course. Under all the study environments, the bridging hydroxyl (OHbr) and terminal hydroxyl (OHt) are identified at 1.1–1.3 eV and 2.1–2.3 eV above lattice oxygen, respectively. This enables novel and complementary approach to characterize reactivity of TiO2 powder. The dynamic behavior of surface-bound water molecules under each study environment is identified, while maintaining a constant distance of 1.3 eV from the position of water vapor. In the dark, the continual supply of both water vapor and oxygen is the key factor retaining the activated state of the TiO2 powder for a time period. Two new surface peaks at 1.7–1.8 and 4.0–4.2 eV above lattice oxygen are designated as peroxides (OOH/H2O2) and H2O2 dissolved in water, respectively. The persistent peroxides on the powder further explain previously observed prolonged oxidation capability of TiO2 powder without light irradiation. PMID:28240300

  7. Characterization of photocatalytic TiO2 powder under varied environments using near ambient pressure X-ray photoelectron spectroscopy

    Science.gov (United States)

    Krishnan, Padmaja; Liu, Minghui; Itty, Pierre A.; Liu, Zhi; Rheinheimer, Vanessa; Zhang, Min-Hong; Monteiro, Paulo J. M.; Yu, Liya E.

    2017-02-01

    Consecutive eight study phases under the successive presence and absence of UV irradiation, water vapor, and oxygen were conducted to characterize surface changes in the photocatalytic TiO2 powder using near-ambient-pressure X-ray photoelectron spectroscopy (XPS). Both Ti 2p and O 1s spectra show hysteresis through the experimental course. Under all the study environments, the bridging hydroxyl (OHbr) and terminal hydroxyl (OHt) are identified at 1.1–1.3 eV and 2.1–2.3 eV above lattice oxygen, respectively. This enables novel and complementary approach to characterize reactivity of TiO2 powder. The dynamic behavior of surface-bound water molecules under each study environment is identified, while maintaining a constant distance of 1.3 eV from the position of water vapor. In the dark, the continual supply of both water vapor and oxygen is the key factor retaining the activated state of the TiO2 powder for a time period. Two new surface peaks at 1.7–1.8 and 4.0–4.2 eV above lattice oxygen are designated as peroxides (OOH/H2O2) and H2O2 dissolved in water, respectively. The persistent peroxides on the powder further explain previously observed prolonged oxidation capability of TiO2 powder without light irradiation.

  8. Characterization and antimicrobial potential of extremely halophilic archaea isolated from hypersaline environments of the Algerian Sahara.

    Science.gov (United States)

    Quadri, Inès; Hassani, Imene Ikrame; l'Haridon, Stéphane; Chalopin, Morgane; Hacène, Hocine; Jebbar, Mohamed

    2016-01-01

    Halophilic archaea were isolated from different chotts and sebkha, dry salt lakes and salt flat respectively, of the Algerian Sahara and characterized using phenotypic and phylogenetic approaches. From 102 extremely halophilic strains isolated, forty three were selected and studied. These strains were also screened for their antagonistic potential and the production of hydrolytic enzymes. Sequencing of the 16S rRNA genes and phylogenetic analysis allowed the identification of 10 archaeal genera within the class Halobacteria: Natrinema (13 strains), Natrialba (12 strains), Haloarcula (4 strains), Halopiger (4 strains), Haloterrigena (3 strains), Halorubrum (2 strains), Halostagnicola (2 strains), Natronococcus, Halogeometricum and Haloferax (1 strain each). The most common producers of antimicrobial compounds belong to the genus Natrinema while the most hydrolytic isolates, with combined production of several enzymes, belong to the genus Natrialba. The strain affiliated to Halopiger djelfamassilliensis was found to produce some substances of interest (halocins, anti-Candida, enzymes). After partial purification and characterization of one of the strains Natrinema gari QI1, we found similarities between the antimicrobial compound and the halocin C8. Therefore, the gene encoding halocin C8 was amplified and sequenced.

  9. Microbial communities of aquatic environments on Heard Island characterized by pyrotag sequencing and environmental data

    Science.gov (United States)

    Allen, Michelle A.; Cavicchioli, Ricardo

    2017-03-01

    Heard Island in the Southern Ocean is a biological hotspot that is suffering the effects of climate change. Significant glacier retreat has generated proglacial lagoons, some of which are open to the ocean. We used pyrotag sequencing of SSU rRNA genes and environmental data to characterize microorganisms from two pools adjacent to animal breeding areas, two glacial lagoons and Atlas Cove (marine site). The more abundant taxa included Actinobacteria, Bacteroidetes and Proteobacteria, ciliates and picoflagellates (e.g. Micromonas), and relatively few Archaea. Seal Pool, which is rich in organic matter, was characterized by a heterotrophic degradative community, while the less eutrophic Atlas Pool had more eucaryotic primary producers. Brown Lagoon, with the lowest nutrient levels, had Eucarya and Bacteria predicted to be oligotrophs, possess small cell sizes, and have the ability to metabolize organic matter. The marine influence on Winston Lagoon was evident by its salinity and the abundance of marine-like Gammaproteobacteria, while also lacking typical marine eucaryotes indicating the system was still functioning as a distinct niche. This is the first microbiology study of Heard Island and revealed that communities are distinct at each location and heavily influenced by local environmental factors.

  10. Characterizing the effects of the protein environment on the reduction potentials of metalloproteins.

    Science.gov (United States)

    Perrin, Bradley Scott; Ichiye, Toshiko

    2013-01-01

    The reduction potentials of electron transfer proteins are critically determined by the degree of burial of the redox site within the protein and the degree of permanent polarization of the polypeptide around the redox site. Although continuum electrostatics calculations of protein structures can predict the net effect of these factors, quantifying each individual contribution is a difficult task. Here, the burial of the redox site is characterized by a dielectric radius R(p) (a Born-type radius for the protein), the polarization of the polypeptide is characterized by an electret potential ϕ(p) (the average electrostatic potential at the metal atoms), and an electret-dielectric spheres (EDS) model of the entire protein is then defined in terms of R(p) and ϕ(p). The EDS model shows that for a protein with a redox site of charge Q, the dielectric response free energy is a function of Q(2), while the electret energy is a function of Q. In addition, R(p) and ϕ(p) are shown to be characteristics of the fold of a protein and are predictive of the most likely redox couple for redox sites that undergo different redox couples.

  11. The use of Polarimetric EMISAR for the Mapping and Characterization of the Semi-Natural Environment

    DEFF Research Database (Denmark)

    Sørensen, Stefán Meulengracht

    , but also methods for detail preservation, which have experienced a rapid growth over the past few years. The main part of this thesis concerns the development of image restoration methods that facilitate the extraction of biotope relevant information from polarimetric SAR data. Because the semi-natural...... environments under study are very small, it is crucial for this investigation that the restoration methods are capable of restoring fine structures as well as preserving homogeneous areas. The restorations are carried out in a signal adaptive mode using MRF in a Bayesian framework. Different a priori models...... on statistics derived from the ratio images is presented together with comparative analyses of restorations using ICM and SA. The relation between the restored polarimetric SAR data and in situ data collected at two semi-natural wetland and grassland areas is investigated using multivariate techniques...

  12. Inter-rater reliability of measures to characterize the tobacco retail environment in Mexico

    Directory of Open Access Journals (Sweden)

    Marissa G Hall

    2015-11-01

    Full Text Available Objective. To evaluate the inter-rater reliability of a data collection instrument to assess the tobacco retail environ- ment in Mexico, after major marketing regulations were implemented. Materials and methods. In 2013, two data collectors independently evaluated 21 stores in two census tracts, through a data collection instrument that assessed the presence of price promotions, whether single cigarettes were sold, the number of visible advertisements, the pre- sence of signage prohibiting the sale of cigarettes to minors, and characteristics of cigarette pack displays. We evaluated the inter-rater reliability of the collected data, through the calculation of metrics such as intraclass correlation coefficient, percent agreement, Cohen’s kappa and Krippendorff’s alpha. Results. Most measures demonstrated substantial or perfect inter-rater reliability. Conclusions. Our results indicate the potential utility of the data collection instrument for future point-of-sale research.

  13. Purification and Characterization of a Bacteriocin Produced by Lactobacillus lactis Isolated from Marine Environment

    Directory of Open Access Journals (Sweden)

    P. Manivasagan

    2010-03-01

    Full Text Available Bacteriocin producing Lactobacillus lactis strain isolated from marine environment, showed broadrange of antibacterial activity against some major food borne pathogens. Maximum bacteriocin production wasobserved at 30°C , pH 6.0 and 1.5% sodium chloride solution. In addition of enzymes, "-amylase, DNase,RNase and lipase were slightly positive effect bacteriocin production. Proteinase K and pepsin were stronglyinhibited bacteriocin production. Among detergents, Sodium dodecyl sulphate (SDS, Tween 80 and TritoneX-100 stimulated bacteriocin production and strongly inhibited by EDTA and urea. The bacteriocin has purifiedby ammonium sulphate precipitate and ion exchange (DEAE cellulose chromatography. Biochemically it waspure protein moiety and the molecular weight was 94 kDa. The study revealed the possibility of usingbacteriocin as a food preservative and the L. lactis strain as probiotic.

  14. Characterization of Salmonella Enteritidis strains isolated from poultry and farm environments in Brazil.

    Science.gov (United States)

    Campioni, F; Zoldan, M M; Falcão, J P

    2014-07-01

    Salmonella Enteritidis is a major causative agent of foodborne outbreaks worldwide. Using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and pulsed-field gel electrophoresis (PFGE), this study assessed the genetic relatedness, the pathogenic potential, and antimicrobial resistance in 60 strains isolated from chickens and the farm environment in Brazil between 2004 and 2010. The resulting concatenated dendrogram of the two methodologies distinguished the strains into two clusters. Some strains isolated from the two sources were indistinguishable. All the strains contained the 13 virulence markers investigated. Forty-four strains were resistant to nalidixic acid. Quinolone resistance presented by many strains suggests that quinolones may have been used to treat chickens. The high prevalence of virulence markers highlights the importance of poultry as vehicles of S. Enteritidis strains that have the potential to cause disease.

  15. Combining On-Line Characterization Tools with Modern Software Environments for Optimal Operation of Polymerization Processes

    Directory of Open Access Journals (Sweden)

    Navid Ghadipasha

    2016-02-01

    Full Text Available This paper discusses the initial steps towards the formulation and implementation of a generic and flexible model centric framework for integrated simulation, estimation, optimization and feedback control of polymerization processes. For the first time it combines the powerful capabilities of the automatic continuous on-line monitoring of polymerization system (ACOMP, with a modern simulation, estimation and optimization software environment towards an integrated scheme for the optimal operation of polymeric processes. An initial validation of the framework was performed for modelling and optimization using literature data, illustrating the flexibility of the method to apply under different systems and conditions. Subsequently, off-line capabilities of the system were fully tested experimentally for model validations, parameter estimation and process optimization using ACOMP data. Experimental results are provided for free radical solution polymerization of methyl methacrylate.

  16. Speciation and persistence of doxycycline in the aquatic environment: Characterization in terms of steady state kinetics.

    Science.gov (United States)

    Zaranyika, Mark F; Dzomba, Pamhidzai; Kugara, Jameson

    2015-01-01

    The aim of the present work was to establish the kinetics for the degradation of doxycycline in the aquatic environment with a view to arriving at a kinetic model that can be used to predict the persistence of antibiotic with confidence. The degradation of doxycycline in both water and sediment phases of aquatic microcosm experiments, as well as in distilled water control experiments, was studied over a period of 90 days. An initial 21% loss due to adsorption by the sediment was observed in the microcosm experiment soon after charging. Biphasic zero-order linear rates of degradation, attributed to microbial degradation of the free and sediment or colloidal particle-adsorbed antibiotic, were observed for both water phase (2.3 × 10(-2) and 4.5 × 10(-3) μgg(-1) day(-1)) and sediment phase (7.9 × 10(-3) and 1.5 × 10(-3) μgg(-1) day(-1)) of the microcosm experiment. The covered distilled water control experiment exhibited a monophasic zero-order linear rate (1.9 × 10(-3) μgg(-1) day(-1)) attributed to hydrolysis, while the distilled water experiment exposed to natural light exhibited biphasic liner rates attributed to a combination of hydrolysis and photolysis (2.9 × 10(-3) μgg(-1) day(-1)) and to microbial degradation (9.8 × 10(-3) μgg(-1) day(-1)). A kinetic model that takes into account hydrolysis, photolysis, microbial degradation as well as sorption/desorption by colloidal and sediment particles is presented to account for the observed zero-order kinetics. The implications of the observed kinetics on the persistence of doxycycline in the aquatic environment are discussed.

  17. Geoparsing text for characterizing urban operational environments through machine learning techniques

    Science.gov (United States)

    Garfinkle, Noah W.; Selig, Lucas; Perkins, Timothy K.; Calfas, George W.

    2017-05-01

    Increasing worldwide internet connectivity and access to sources of print and open social media has increased near realtime availability of textual information. Capabilities to structure and integrate textual data streams can contribute to more meaningful representations of operational environment factors (i.e., Political, Military, Economic, Social, Infrastructure, Information, Physical Environment, and Time [PMESII-PT]) and tactical civil considerations (i.e., Areas, Structures, Capabilities, Organizations, People and Events [ASCOPE]). However, relying upon human analysts to encode this information as it arrives quickly proves intractable. While human analysts possess an ability to comprehend context in unstructured text far beyond that of computers, automated geoparsing (the extraction of locations from unstructured text) can empower analysts to automate sifting through datasets for areas of interest. This research evaluates existing approaches to geoprocessing as well as initiating the research and development of locally-improved methods of tagging parts of text as possible locations, resolving possible locations into coordinates, and interfacing such results with human analysts. The objective of this ongoing research is to develop a more contextually-complete picture of an area of interest (AOI) including human-geographic context for events. In particular, our research is working to make improvements to geoparsing (i.e., the extraction of spatial context from documents), which requires development, integration, and validation of named-entity recognition (NER) tools, gazetteers, and entity-attribution. This paper provides an overview of NER models and methodologies as applied to geoparsing, explores several challenges encountered, presents preliminary results from the creation of a flexible geoparsing research pipeline, and introduces ongoing and future work with the intention of contributing to the efficient geocoding of information containing valuable

  18. Characterization of the internal ion environment of biofilms based on charge density and shape of ion.

    Science.gov (United States)

    Kurniawan, Andi; Tsuchiya, Yuki; Eda, Shima; Morisaki, Hisao

    2015-12-01

    Biofilm polymers contain both electrically positively and negatively charged sites. These charged sites enable the biofilm to trap and retain ions leading to an important role of biofilm such as nutrient recycling and pollutant purification. Much work has focused on the ion-exchange capacity of biofilms, and they are known to adsorb ions through an exchange mechanism between the ions in solution and the ions adsorbed to the charged sites on the biofilm polymer. However, recent studies suggest that the adsorption/desorption behavior of ions in a biofilm cannot be explained solely by this ion exchange mechanism. To examine the possibility that a substantial amount of ions are held in the interstitial region of the biofilm polymer by an electrostatic interaction, intact biofilms formed in a natural environment were immersed in distilled water and ion desorption was investigated. All of the detected ion species were released from the biofilms over a short period of time, and very few ions were subsequently released over more time, indicating that the interstitial region of biofilm polymers is another ion reserve. The extent of ion retention in the interstitial region of biofilms for each ion can be determined largely by charge density, |Z|/r, where |Z| is the ion valence as absolute value and r is the ion radius. The higher |Z|/r value an ion has, the stronger it is retained in the interstitial region of biofilms. Ion shape is also a key determinant of ion retention. Spherical and non-spherical ions have different correlations between the condensation ratio and |Z|/r. The generality of these findings were assured by various biofilm samples. Thus, the internal regions of biofilms exchange ions dynamically with the outside environment.

  19. Characterization of the Geosynchronous Plasma Environment for the SENSER/RROE Optical Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Woodroffe, Jesse Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-08

    In this report, we summarize available research in order to characterize expected rates of particle incidence on the SENSER/RROE optical instrument. We first investigate the “normal” background levels using data from statistical studies of spacecraft in geosynchronous orbit and empirical models. We then consider “worst case” scenarios based on event studies in which extreme fluxes have been observed. We use these data to define “maximum” rates of particle incidence. We then consider how incident particles will actually produce counts in the instrument by considering the effects of screening by the instrument housing and the possibility of direct particle access to the housing, with rates for both primary access and secondary electron generation.

  20. Combining Passive Sampling with Toxicological Characterization of Complex Mixtures of Pollutants from the Aquatic Environment.

    Science.gov (United States)

    Jahnke, Annika; Witt, Gesine; Schäfer, Sabine; Haase, Nora; Escher, Beate I

    2016-08-04

    The combination of polymer-based passive sampling to collect complex environmental mixtures of pollutants, the transfer of these mixtures into bioassays, and their related toxicological characterization is still in its infancy. However, this approach has considerable potential to improve environmental hazard and risk assessment for two reasons. First, the passive sampler collects a broad range of chemicals representing the fraction of compounds available for diffusion and (bio)uptake, excluding a large part of the matrix; thus, extensive sample cleanup which could discriminate certain compounds can be avoided. Second, the toxicological characterization of samples using bioassays is complementary to chemical (target) analysis within environmental monitoring because it captures all chemicals exerting the same mode of toxic action and acting jointly in mixtures, thus providing a comprehensive picture of their overall combined effects. The scientific literature describes a range of examples from the water phase where passive sampling is usually carried out in the kinetic uptake regime for most chemicals although some may already have reached equilibrium. The composition of the chemical mixture changes from the water phase to the passive sampling material because of kinetic effects and polymer/water partition coefficients which depend on the chemicals' hydrophobicity. In contrast, only a few applications in sediment and biota have been described, but amongst these some pioneering studies have demonstrated the feasibility and potential of this combined approach. This chapter gives an overview of what has been carried out in this research area, focusing on opportunities and challenges, and points out desirable future developments with a focus on the importance of choosing a suitable combination of sampling and dosing to transfer (or re-establish) the environmental mixture into the bioassay.

  1. Micelle dynamic simulation and physicochemical characterization of biorelevant media to reflect gastrointestinal environment in fasted and fed states.

    Science.gov (United States)

    Xie, XiaoYu; Cardot, Jean-Michel; Garrait, Ghislain; Thery, Vincent; El-Hajji, Mohamed; Beyssac, Eric

    2014-10-01

    The characterization of biorelevant media simulating the upper part of the gastrointestinal tract in the fasted and fed states was investigated by classical determination of physicochemical parameters such as pH, osmolality, surface tension and results were compared to in vivo physiological data. Incorporation of fatty material, in order to better simulate the influence of high fat meal was also performed. Stability and characterization of this medium was studied and compared to classical FeSSIF. Micelle characterization and computer dynamic simulation were performed in order to understand the interaction between lecithin and taurocholate and possible interactions between mixed micelle and drugs. The addition of NaTc, lecithin, and/or fatty materials has no influence on pH and osmolality, whereas the presence of fatty material modifies the surface tension. Values of FaSSIF and FeSSIF are in accordance with in vivo parameters and the presence of micelles can simulate the gastrointestinal environment. Modelization of micelles by computer simulation led to a model of mixed micelles in which structures of NaTc interact either by their hydrophilic or hydrophobic phase to give a bilayer stable model in which the lecithin molecule can insert its long carbon chain. The micelle structure is stable and can enhance dissolution of hydrophobic molecules by hydrophobic interaction with the numerous hydrophobic spaces available in the multilayer hydrophilic/hydrophobic layer.

  2. Improving retrospective characterization of the food environment for a large region in the United States during a historic time period.

    Science.gov (United States)

    Auchincloss, Amy H; Moore, Kari A B; Moore, Latetia V; Diez Roux, Ana V

    2012-11-01

    Access to healthy foods has received increasing attention due to growing prevalence of obesity and diet-related health conditions yet there are major obstacles in characterizing the local food environment. This study developed a method to retrospectively characterize supermarkets for a single historic year, 2005, in 19 counties in 6 states in the USA using a supermarket chain-name list and two business databases. Data preparation, merging, overlaps, added-value amongst various approaches and differences by census tract area-level socio-demographic characteristics are described. Agreement between two food store databases was modest: 63%. Only 55% of the final list of supermarkets were identified by a single business database and selection criteria that included industry classification codes and sales revenue ≥$2 million. The added-value of using a supermarket chain-name list and second business database was identification of an additional 14% and 30% of supermarkets, respectively. These methods are particularly useful to retrospectively characterize access to supermarkets during a historic period and when field observations are not feasible and business databases are used.

  3. Magnetic properties of Jiaxian red clay sequences from northern Chinese Loess Plateau and its paleoclimatic significance

    Institute of Scientific and Technical Information of China (English)

    QIANG; Xiaoke; AN; Zhisheng; LI; Huamei; CHANG; Hong

    2005-01-01

    Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the Chinese Loess Plateau as well as the marked properties of themselves, magnetic minerals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak paleosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern Chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern Chinese Loess Plateau. We conclude that the paleoclimatic environment is different between northern and eastern/southern Chinese Loess Plateau, and it should be more arid in northern Chinese Loess Plateau.

  4. Numerical study of surface energy partitioning on the Tibetan plateau: comparative analysis of two biosphere models

    Directory of Open Access Journals (Sweden)

    J. Hong

    2010-02-01

    Full Text Available The Tibetan Plateau is a critical region in the research of biosphere-atmosphere interactions on both regional and global scales due to its relation to Asian summer monsoon and El Niño. The unique environment on the Plateau provides valuable information for the evaluation of the models' surface energy partitioning associated with the summer monsoon. In this study, we investigated the surface energy partitioning on this important area through comparative analysis of two biosphere models constrained by the in-situ observation data. Indeed, the characteristics of the Plateau provide a unique opportunity to clarify the structural deficiencies of biosphere models as well as new insight into the surface energy partitioning on the Plateau. Our analysis showed that the observed inconsistency between the two biosphere models was mainly related to: 1 the parameterization for soil evaporation; 2 the way to deal with roughness lengths of momentum and scalars; and 3 the parameterization of subgrid velocity scale for aerodynamic conductance. Our study demonstrates that one should carefully interpret the modeling results on the Plateau especially during the pre-monsoon period.

  5. Numerical study of surface energy partitioning on the Tibetan Plateau: comparative analysis of two biosphere models

    Directory of Open Access Journals (Sweden)

    J. Hong

    2009-11-01

    Full Text Available The Tibetan Plateau is a critical region in the research of biosphere-atmosphere interactions on both regional and global scales due to its relation to Asian summer monsoon and El Niño. The unique environment on the Plateau provides valuable information for the evaluation of the models' surface energy partitioning associated with the summer monsoon. In this study, we investigated the surface energy partitioning on this important area through comparative analysis of two biosphere models constrained by the in-situ observation data. Indeed, the characteristics of the Plateau provide a unique opportunity to clarify the structural deficiencies of biosphere models as well as new insight into the surface energy partitioning on the Plateau. Our analysis showed that the observed inconsistency between the two biosphere models was mainly related to: 1 the parameterization for soil evaporation; 2 the way to deal with roughness lengths of momentum and scalars; and 3 the parameterization of subgrid velocity scale for aerodynamic conductance. Our study demonstrates that one should carefully interpret the modeling results on the Plateau especially during the pre-monsoon period.

  6. Desert-steppe migration on the Loess Plateau at about 450 kaBP

    Institute of Scientific and Technical Information of China (English)

    ZHAOJingbo

    2005-01-01

    According to the field investigation, observation by an electronic microscope and x-ray identification and chemical analysis, desert-steppe migration in the Loess Plateau at about 450 kaBP was studied. The data show that gypsum illuvial horizon indicating the desert-steppe environment developed in the early stage of the formation of the fifth layer loess in Shaoling tableland in Chang'an and Bailu tableland in Xran of Shaanxi are situated in the southern Loess Plateau. This indicates that remarkable drying occurred, a large-scope migration of desert steppe took place toward south and the climate zone migrated 5 degrees in latitude to south which is the largest migration range indicated by geochemical indexes. The desert-steppe and more wild environment distributed widely on the Loess Plateau at that time. The development of gypsum also indicates that the climate changed at 450 kaBP from monsoon climate to nonmonsoon climate in the Loess Plateau, and the region was not affected by summer monsoon and was in the cold and dry environment of nonmonsoon climate. Annual mean nrecinitation was about 200 rnm. 400 mm less at that time than at oresent.

  7. Characterizing the Response of Composite Panels to a Pyroshock Induced Environment Using Design of Experiments Methodology

    Science.gov (United States)

    Parsons, David S.; Ordway, David; Johnson, Kenneth

    2013-01-01

    This experimental study seeks to quantify the impact various composite parameters have on the structural response of a composite structure in a pyroshock environment. The prediction of an aerospace structure's response to pyroshock induced loading is largely dependent on empirical databases created from collections of development and flight test data. While there is significant structural response data due to pyroshock induced loading for metallic structures, there is much less data available for composite structures. One challenge of developing a composite pyroshock response database as well as empirical prediction methods for composite structures is the large number of parameters associated with composite materials. This experimental study uses data from a test series planned using design of experiments (DOE) methods. Statistical analysis methods are then used to identify which composite material parameters most greatly influence a flat composite panel's structural response to pyroshock induced loading. The parameters considered are panel thickness, type of ply, ply orientation, and pyroshock level induced into the panel. The results of this test will aid in future large scale testing by eliminating insignificant parameters as well as aid in the development of empirical scaling methods for composite structures' response to pyroshock induced loading.

  8. The Dust Management Project: Characterizing Lunar Environments and Dust, Developing Regolith Mitigation Technology and Simulants

    Science.gov (United States)

    Hyatt, Mark J.; Straka, Sharon A.

    2010-01-01

    A return to the Moon to extend human presence, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth?s economic sphere, will require investment in developing new technologies and capabilities to achieve affordable and sustainable human exploration. From the operational experience gained and lessons learned during the Apollo missions, conducting long-term operations in the lunar environment will be a particular challenge, given the difficulties presented by the unique physical properties and other characteristics of lunar regolith, including dust. The Apollo missions and other lunar explorations have identified significant lunar dust-related problems that will challenge future mission success. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it?s potentially harmful effects on exploration systems and human explorers. The Dust Management Project (DMP) is tasked with the evaluation of lunar dust effects, assessment of the resulting risks, and development of mitigation and management strategies and technologies related to Exploration Systems architectures. To this end, the DMP supports the overall goal of the Exploration Technology Development Program (ETDP) of addressing the relevant high priority technology needs of multiple elements within the Constellation Program (CxP) and sister ETDP projects. Project scope, plans, and accomplishments will be presented.

  9. Characterization and molecular interpretation of the photosynthetic traits of Lonicera confusa in Karst environment.

    Directory of Open Access Journals (Sweden)

    Geng Wu

    Full Text Available Lonicera confusa was a medical plant which could adapt to the Ca-rich environment in the karst area of China. The photosynthesis, relative chlorophyll content,differentially expressed genes (DEGs and differentially expressed proteins (DEPs of L. confusa that cultivated in calcareous and sandstone soils were investigated. The results showed that the relative chlorophyll content and net photosynthesis rate of L. confusa in calcareous soil are much higher than that planted in sandstone soil, the higher content of calcium might play a role in keeping the chloroplast from harm and showed higher photosynthesis rate. The transpiration and stomata conductance were decreased in calcareous soil, which might result from the closure of stomata. The GeneFishing and proteomic results showed that the expression of DEGs and DEPs were critical for photosynthesis and stomata closure, such as RuBisCO, photosynthetic electron transfer c and malate dehydrogenase varied in the leaves of L. confusa that cultivated in different soils. These DEGs or DEPs were further found to be directly or indirectly regulated by calcium sensor proteins. This study enriched our knowledge of the molecular mechanism of high net photosynthesis rate and lower transpiration of L. confusa that cultivated in the calcareous soil in some degree.

  10. Characterization of an acoustic actuation mechanism for robotic propulsion in low Reynolds number environments

    Science.gov (United States)

    House, Christopher; Armstrong, Jenelle; Burkhardt, John; Firebaugh, Samara

    2014-06-01

    With the end goal of medical applications such as non-invasive surgery and targeted drug delivery, an acoustically driven resonant structure is proposed for microrobotic propulsion. At the proposed scale, the low Reynolds number environment requires non-reciprocal motion from the robotic structure for propulsion; thus, a "flapper" with multiple, flexible joints, has been designed to produce excitation modes that involve the necessary flagella-like bending for non-reciprocal motion. The key design aspect of the flapper structure involves a very thin joint that allows bending in one (vertical) direction, but not the opposing direction. This allows for the second mass and joint to bend in a manner similar to a dolphin's "kick" at the bottom of their stroke, resulting in forward thrust. A 130 mm x 50 mm x 0.2 mm prototype of a swimming robot that utilizes the flapper was fabricated out of acrylic using a laser cutter. The robot was tested in water and in a water-glycerine solution designed to mimic microscale fluid conditions. The robot exhibited forward propulsion when excited by an underwater speaker at its resonance mode, with velocities up to 2.5 mm/s. The robot also displayed frequency selectivity, leading to the possibility of exploring a steering mechanism with alternatively tuned flappers. Additional tests were conducted with a robot at a reduced size scale.

  11. Characterization of Doayo and Kapsiki taurine cattle breeds of Cameroon in their natural environment.

    Science.gov (United States)

    Ebangi, A Lot; Achukwi, M D; Messine, O; Abba, D

    2011-08-01

    Data were collected on live weight (LW), heart girth (HG), height-at-withers (HW), trunk length (TL), age, sex, and coat color of 207 taurines cattle--122 of the Doayo (Namchi) breed and 85 of the Kapsiki (Kirdi) breed. The animals, aged 1 to 20 years, were selected from 60 herds randomly selected from villages of Poli of Faro and Mokolo of Tsanga, divisions of the North and Far North Regions of Cameroon. The data were analyzed using the SAS program with a linear model, applying standard tests. Results indicated no breed effect (P > 0.05) in the growth trends of LW, HG, HW, and TL. HG and TL were highly significantly (P 0.05) significantly. The breeds attained maturity as from 4 years. In the absence of breed effect (P > 0.05), a single regression equation was established for the estimation of live weight as thus LW = -244.42 (±22.57) kg + 2.49 (±0.23) HG + 1.04 (±0.25) TL, with HG contributing up to 70% of total variation and TL, 2%. This equation could be used to develop a measuring band useful in the rural environment for commercial and clinical veterinary purposes.

  12. Annual cycle of size-resolved organic aerosol characterization in an urbanized desert environment

    Science.gov (United States)

    Cahill, Thomas M.

    2013-06-01

    Studies of size-resolved organic speciation of aerosols are still relatively rare and are generally only conducted over short durations. However, size-resolved organic data can both suggest possible sources of the aerosols and identify the human exposure to the chemicals since different aerosol sizes have different lung capture efficiencies. The objective of this study was to conduct size-resolved organic aerosol speciation for a calendar year in Phoenix, Arizona to determine the seasonal variations in both chemical concentrations and size profiles. The results showed large seasonal differences in combustion pollutants where the highest concentrations were observed in winter. Summertime aerosols have a greater proportion of biological compounds (e.g. sugars and fatty acids) and the biological compounds represent the largest fraction of the organic compounds detected. These results suggest that standard organic carbon (OC) measurements might be heavily influenced by primary biological compounds particularly if the samples are PM10 and TSP samples. Several large dust storms did not significantly alter the organic aerosol profile since Phoenix resides in a dusty desert environment, so the soil and plant tracer of trehalose was almost always present. The aerosol size profiles showed that PAHs were generally most abundant in the smallest aerosol size fractions, which are most likely to be captured by the lung, while the biological compounds were almost exclusively found in the coarse size fraction.

  13. Characterizing fluvial systems at basin scale by fuzzy signatures of hydromorphological drivers in data scarce environments

    Science.gov (United States)

    Schmitt, R.; Bizzi, S.; Castelletti, A.

    2014-06-01

    Despite the relevance of river hydromorphology (HYMO) for integrated water resource management, consistent geomorphic information at the scale of whole river basin is still scarce, especially in emerging economies. In this paper, we propose a new, scalable and globally applicable framework to analyze and classify fluvial systems in data-scarce environments. The framework is based on a data-driven analysis of a multivariate data set of 6 key hydro-morphologic drivers derived using freely available remote-sensing information and several in situ hydrological time series. Core of the framework is a fuzzy classifier that assigns a characteristic signature of HYMO drivers to individual river reaches. We demonstrate the framework on the Red River Basin, a large, trans-boundary river basin in Vietnam and China, where human-induced morphological change, concretely endangering local livelihoods, is contrasted by very limited HYMO information. The derived HYMO information covers spatial scales from the entire basin to individual reaches. It conveys relevant information on subbasin hydro-morphologic characteristic as well as on local geomorphologic forms and processes. The fuzzy classifier successfully distinguishes abrupt from continuous downstream change and spatially dissects the river system in segments with homogeneous hydro-morphologic forcings. Successful numerical modelling of morphologic forms and process rates based on the HYMO signatures indicates that the multivariate, basin-scale classification captures relevant morphological drivers, outperforms an analysis based on local drivers only, and can support river management from diverse, morphology related perspectives over a wide range of scales.

  14. The Hikurangi Plateau: Tectonic Ricochet and Accretion

    Science.gov (United States)

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

    2015-04-01

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

  15. Identification and characterization of humic substances-degrading bacterial isolates from an estuarine environment.

    Science.gov (United States)

    Esham; Ye; Moran

    2000-12-01

    Bacterial isolates were obtained from enrichment cultures containing humic substances extracted from estuarine water using an XAD-8 resin. Eighteen isolates were chosen for phylogenetic and physiological characterization based on numerical importance in serial dilutions of the enrichment culture and unique colony morphology. Partial sequences of the 16S rRNA genes indicated that six of the isolates were associated with the alpha subclass of Proteobacteria, three with the gamma-Proteobacteria, and nine with the Gram-positive bacteria. Ten isolates degraded at least one (and up to six) selected aromatic single-ring compounds. Six isolates showed ability to degrade [(14)C]humic substances derived from the dominant salt marsh grass in the estuary from which they were isolated (Spartina alterniflora), mineralizing 0.4-1.1% of the humic substances over 4 weeks. A mixture of all 18 isolates did not degrade humic substances significantly faster than any of the individual strains, however, and no isolate degraded humic substances to the same extent as the natural marine bacterial community (3.0%). Similar studies with a radiolabeled synthetic lignin ([beta-(14)C]dehydropolymerisate) showed measurable levels of degradation by all 18 bacteria (3.0-8.8% in 4 weeks), but mineralization levels were again lower than that observed for the natural marine bacterial community (28.2%). Metabolic capabilities of the 18 isolates were highly variable and generally did not map to phylogenetic affiliation.

  16. The characterization of a DIRSIG simulation environment to support the inter-calibration of spaceborne sensors

    Science.gov (United States)

    Ambeau, Brittany L.; Gerace, Aaron D.; Montanaro, Matthew; McCorkel, Joel

    2016-09-01

    Climate change studies require long-term, continuous records that extend beyond the lifetime, and the temporal resolution, of a single remote sensing satellite sensor. The inter-calibration of spaceborne sensors is therefore desired to provide spatially, spectrally, and temporally homogeneous datasets. The Digital Imaging and Remote Sensing Image Generation (DIRSIG) tool is a first principle-based synthetic image generation model that has the potential to characterize the parameters that impact the accuracy of the inter-calibration of spaceborne sensors. To demonstrate the potential utility of the model, we compare the radiance observed in real image data to the radiance observed in simulated image from DIRSIG. In the present work, a synthetic landscape of the Algodones Sand Dunes System is created. The terrain is facetized using a 2-meter digital elevation model generated from NASA Goddard's LiDAR, Hyperspectral, and Thermal (G-LiHT) imager. The material spectra are assigned using hyperspectral measurements of sand collected from the Algodones Sand Dunes System. Lastly, the bidirectional reflectance distribution function (BRDF) properties are assigned to the modeled terrain using the Moderate Resolution Imaging Spectroradiometer (MODIS) BRDF product in conjunction with DIRSIG's Ross-Li capability. The results of this work indicate that DIRSIG is in good agreement with real image data. The potential sources of residual error are identified and the possibilities for future work are discussed.

  17. [Cholera Vibrio biofilm: production, characterization and role in reservation of causative agent in water environment].

    Science.gov (United States)

    Kulikalova, E S; Urbanovich, L Ia; Sappo, S G; Mironova, L V; Markov, E Iu; Mal'nik, V V; Korzun, V M; Mitkeeva, S K; Balakhonov, S V

    2015-01-01

    Experimental production, characterization and evaluation of the role of cholera vibrio biofilm. 33 strains of Vibrio cholerae eltor O1 and V. cholerae O139 of various epidemic significance and origin were studied in a series of experiments by bacteriologic, microscopic (light-optic, luminescent, scanning electron microscopy), molecular genetics, spectrophotometric and statistical methods. Formation of a biofilm involving inter-cellular bonds, pili and extracellular material and variability of the microorganism (RO-phenotype and transition into uncultivable forms) was shown at various temperature and substrate conditions. A more pronounced ability to form biofilms was detected for strains isolated from environmental samples compared with isolated from clinical material regardless of their epidemic significance. Toxigenic strains of eltor biovar (from surface reservoirs during cholera outbreaks) have demonstrated the highest parameters of optical density compared with toxigenic clinical isolates and non-toxigenic O1 and O139 serogroup cultures. The presence of mbaA1 and mbaA2, vpsR, toxR, hapA genes is common for strains that form a biofilm. The data obtained confirm the role of biofilm in reservation of cholera vibrio strains of various epidemic significance in saprophytic phase of microorganism existence.

  18. Application of RAPD for molecular characterization of plant species of medicinal value from an arid environment.

    Science.gov (United States)

    Arif, I A; Bakir, M A; Khan, H A; Al Farhan, A H; Al Homaidan, A A; Bahkali, A H; Al Sadoon, M; Shobrak, M

    2010-11-09

    The use of highly discriminatory methods for the identification and characterization of genotypes is essential for plant protection and appropriate use. We utilized the RAPD method for the genetic fingerprinting of 11 plant species of desert origin (seven with known medicinal value). Andrachne telephioides, Zilla spinosa, Caylusea hexagyna, Achillea fragrantissima, Lycium shawii, Moricandia sinaica, Rumex vesicarius, Bassia eriophora, Zygophyllum propinquum subsp migahidii, Withania somnifera, and Sonchus oleraceus were collected from various areas of Saudi Arabia. The five primers used were able to amplify the DNA from all the plant species. The amplified products of the RAPD profiles ranged from 307 to 1772 bp. A total of 164 bands were observed for 11 plant species, using five primers. The number of well-defined and major bands for a single plant species for a single primer ranged from 1 to 10. The highest pair-wise similarities (0.32) were observed between A. fragrantissima and L. shawii, when five primers were combined. The lowest similarities (0) were observed between A. telephioides and Z. spinosa; Z. spinosa and B. eriophora; B. eriophora and Z. propinquum. In conclusion, the RAPD method successfully discriminates among all the plant species, therefore providing an easy and rapid tool for identification, conservation and sustainable use of these plants.

  19. Molecular characterization and lipase profiling of the yeasts isolated from environments contaminated with petroleum.

    Science.gov (United States)

    Yalçın, H Tansel; Corbacı, Cengiz; Uçar, Füsun B

    2014-07-01

    In the present study, 120 yeast isolates from different sources (active sludge, soil, and wastewater samples obtained from petroleum refinery and soil contaminated by petroleum) were obtained. The yeast isolates were screened for lipase production and twelve of the isolates (D3, D17, D24, D27, D30, D38, D40, D42, D44, D46, D56, and D57) exhibited lipase activity. Molecular characterization of the yeasts showing the lipase production was performed with RFLP of ITS1-5.8S-ITS2 and 18S rRNA and sequence analysis of D1/D2 domain of 26S rRNA. The 26S rRNA sequencing revealed that four new strains, D38, D40, D44 and D57 identified as Rhodotorula slooffiae, Candida davisiana, Cryptococcus diffluens, and Cryptococcus uzbekistanensis, respectively, are lipase producing yeast species. This study is the first report showed lipase production by these species. The other lipase producing strains identified as Candida parapsilosis (D3), Rhodotorula muciloginosa (D17 and D42), Cryptococcus albidus (D24, D27, D30, and D56), and Wickerhamomyces anomalus (D46). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Peopling the Tibetan plateau: insights from archaeology.

    Science.gov (United States)

    Aldenderfer, Mark

    2011-01-01

    Recent studies of the genome of modern Tibetans have revealed the existence of genes thought to provide an adaptive advantage for life at high elevation. Extrapolating from this discovery, some researchers now argue that a Tibetan-Han split occurred no more than 2750 yr ago. This date is implausible, and in this paper I review the archaeological data from the Tibetan plateau as one means by which to examine the veracity of this assertion. Following a review of the general state of knowledge of Tibetan prehistory, which is unfortunately only at its beginnings, I first examine the data that speak to the initial peopling of the plateau and assess the evidence that traces of their presence can be seen in modern Tibetans today. Although the data are sparse, both archaeology and genetics suggest that the plateau was occupied in the Late Pleistocene, perhaps as early as 30,000 yr ago, and that these early peoples have left a genetic signature in modern Tibetans. I then turn to the evidence for later migrations and focus on the question of the timing of the establishment of permanent settled villages on the plateau. Three areas of the plateau-northeastern Qinghai, extreme eastern Tibet, and the Yarlung Tsangpo valley-have evidence of permanent settlements dating from ca. 6500, 5900, and 3750 yr ago, respectively. These data are not consonant with the 2750 yr ago date for the split and suggest at a minimum that the plateau has been occupied substantially longer and, further, that multiple migrations at different times and from different places have created a complex mosaic of population history. © Mary Ann Liebert, Inc.

  1. MEMS-based gradiometer for the complete characterization of Martian magnetic environment

    Science.gov (United States)

    Mesa, Jose Luis; Ciudad, David; McHenry, Michael E.; Aroca, Claudio; Díaz-Michelena, Marina

    2013-04-01

    The in-situ determination of the Martian magnetic field is one of the most important and ambitious objectives in Mars exploration, because its implications in paleomagnetism, tectonics and mineral determination. To place sensors on Mars is a complicated task, due to the extreme conditions of the planet surface and also because of the relative low budget devoted to this kind of instrument: low power, mass, volume and the need to operate in a magnetically noise environment. A complete and accurate measurement of the magnetic environment includes the determination of both magnitude and gradient of the magnetic field (B). There are many developments of magnetometers with the characteristics mentioned before [2], but the question about gradient is not that well solved and most gradient sensors are based on a couple of magnetometers separated a certain distance [2, 3]. The aim of this abstract is to introduce a new MEMS based robust gradiometer for the point measurement of the field gradient with the ultimate goal to perform in situ measurement on Mars and shed some light in the magnetic anomalies explanation of the Red Planet. Since in some conditions ?ׯB = 0, we assume knowing six of the nine components is sufficient to reconstruct entirely the magnetic field gradient. The device proposed consists of a set of six cantilevers to measure these six components (with resolution in the order of 1 nT/mm) combined either with another miniaturized and more accurate magnetometer (with resolution below the nT) for the measurement of the field vector. Every component system consists of a cantilever with an appropriate geometry, an excitation coil and a mechanism to generate a field gradient. The cantilevers are made of piezoelectric material (bimorph, with two piezoelectric layers) covered by a soft ferromagnetic material (of Iron-Nickel base). Is explained below the working principle for one component. When the excitation system generates an alternating magnetic field (enough

  2. Comparative phenotypic characterization of Vibrio cholerae isolates collected from aquatic environments of Georgia.

    Science.gov (United States)

    Kokashvili, T; Elbakidze, T; Jaiani, E; Janelidze, N; Kamkamidze, G; Whitehouse, C; Huq, A; Tediashvili, M

    2013-11-01

    Vibrio cholerae is ubiquitous in aquatic environment inhabiting marine, fresh and brackish waters. V. cholerae serotypes O1 and O139 cause the devastating diarrheal disease cholera, which is often fatal without proper treatment. Little is known regarding the abundance and diversity of clinically important nonhalophilic vibrios in the South Caucasus region, particularly in Georgia. Here we provide the data on the Georgian environmental strains of V. cholerae isolated in 2006-2009 years from the coastal waters of the Black Sea and inland water reservoirs near Tbilisi. In total, 846 V. cholerae strains were collected from the water samples, most of them (705 strains) obtained from fresh water lakes. Isolation pattern of V. cholerae showed obvious seasonality with the highest isolation rates in late summer - early autumn. Twenty-nine isolates of V. cholerae were attributed to the O1 serotype based on serological studies and PCR identification and were further grouped by biochemical properties into classical and El Tor biotypes as well as hybrids. The study of antibiotic susceptibility profiles for V. cholerae isolates showed that 95% were sensitive to tetracycline, 91% to doxycycline, and 91% to ciprofloxacin. Interestingly, the freshwater isolates appeared to be more resistant to antibiotics than the Black Sea isolates. Among Black Sea isolates of V. cholerae toxigenic strains of O1 serotype revealed higher antibiotic resistance compared to non- O1/non-O139 isolates. In addition, V. cholerae O1 and non- O1/non-O139 isolates differed by phage susceptibility profiles, with higher diversity within the population of environmental non-O1/non-O139 V. cholerae isolates.

  3. Plateau-insulator transition in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Amado, M; Diez, E; Caridad, J M [Laboratorio de Bajas Temperaturas, Universidad de Salamanca, E-37008 Salamanca (Spain); Lopez-Romero, D [CT-ISOM, Universidad Politecnica de Madrid, E-28040 Madrid (Spain); Rossella, F; Dionigi, F; Bellani, V [Dipartimento di Fisica ' A Volta' and CNISM, Universita degli studi di Pavia, I-27100 Pavia (Italy); Maude, D K, E-mail: marioam@fis.ucm.e [Laboratoire National des Champs Magnetiques Intenses, F-38042 Grenoble (France)

    2010-05-15

    We investigate the quantum Hall effect (QHE) in a graphene sample with Hall-bar geometry close to the Dirac point at high magnetic fields up to 28 T. We have discovered a plateau-insulator quantum phase transition passing from the last plateau for the integer QHE in graphene to an insulator regime {nu}=-2{yields}{nu}=0. The analysis of the temperature dependence of the longitudinal resistance gives a value for the critical exponent associated with the transition equal to {kappa}=0.58{+-}0.03.

  4. Isolation and characterization of Escherichia coli recovered from Maryland apple cider and the cider production environment.

    Science.gov (United States)

    Senkel, I Arthur; Jolbitado, Beverly; Zhang, Yifan; White, David G; Ayers, Sherry; Meng, Jianghong

    2003-12-01

    Contaminated apple cider has been implicated in several Escherichia coli O157:H7 outbreaks. In an attempt to investigate sources and modes of entry of E. coli into apple cider, samples of fresh apple, pomace, and cider and equipment and mill floor swabs were analyzed for standard plate counts (SPC), total coliforms (TC), fecal coliforms (FC), and E. coli. E. coli was isolated from 14 (33%) of 42 samples of bottled fresh cider, from food equipment in 6 (67%) of 9 mills, and from apples, pomace, or cider in 7 (78%) of 9 mills. Seventy-five E. coli isolates were further characterized for Shiga toxin-producing E. coli (STEC)-associated virulence factors, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) type. No E. coli O157:H7 or other STEC was identified. Serotyping and PFGE revealed 64 distinct profiles, suggesting that recovered E. coli arose from multiple independent sources. However, on one occasion, E. coli isolated from the source apple sample was closely related to the E. coli identified in the finished cider sample. E. coli isolates were further tested for antimicrobial susceptibility to 17 antimicrobial agents of human and veterinary importance. Fourteen (19%) of the 75 isolates were resistant to at least one of the antimicrobial agents tested, and 9 (12%) were resistant to at least two of these agents. Of the resistant isolates recovered, 64% were resistant to tetracycline and 57% were resistant to streptomycin. Overall, the level of E. coli contamination in source apple samples did not differ significantly from those in samples of pomace, cider at the press, and cider entering the bottling tank; therefore, source apples cannot be dismissed as a potential contributor of E. coli to the cider-making process.

  5. DYNAMICS OF BRÂGLEZ RIVERBED (SOMEŞAN PLATEAU

    Directory of Open Access Journals (Sweden)

    V. ARGHIUŞ

    2012-03-01

    Full Text Available Dynamics of Brâglez Riverbed (Someşan Plateau. The main left tributaries of Someş along Surduc – Jibou sector (Brâglez, Almaş and Agrij, are characterized by the presence of obvious processes of lateral and vertical erosion at the level of the riverbeds. The field observations, as well as the position of these rivers and their catchment areas in the neighborhood of the lower Someş subsidence area, would easily be grounds for explaining the riverbed processes as caused by an unstable fluvial base level. More precisely, this base level would be moving downwards under the influence of subsidence movements of Tisa Plain or even because of the subsidence affecting Guruslău Basin. Starting from these more or less speculative deductions, this paper aims at checking and confirming the above-mentioned explanations or finding other causes for the dynamics of riverbed processes. In this sense, we analysed a correlation between the drainage in the catchment area and at the level of the riverbeds, on one hand, and the riverbed geomorphological processes, on the other hand. Brâglez River (in western Someşan Plateau will be considered as a study case, as it provides an accelerated dynamics of riverbed processes. This situation will be compared with the one in the eastern part of the same plateau, where rivers like Borşa, Luna or Lujerdiu do not present obvious riverbed processes despite the similar climatic and geological conditions.

  6. Characterization of aerobic spore-forming bacteria associated with industrial dairy processing environments and product spoilage.

    Science.gov (United States)

    Lücking, Genia; Stoeckel, Marina; Atamer, Zeynep; Hinrichs, Jörg; Ehling-Schulz, Monika

    2013-09-02

    Due to changes in the design of industrial food processing and increasing international trade, highly thermoresistant spore-forming bacteria are an emerging problem in food production. Minimally processed foods and products with extended shelf life, such as milk products, are at special risk for contamination and subsequent product damages, but information about origin and food quality related properties of highly heat-resistant spore-formers is still limited. Therefore, the aim of this study was to determine the biodiversity, heat resistance, and food quality and safety affecting characteristics of aerobic spore-formers in the dairy sector. Thus, a comprehensive panel of strains (n=467), which originated from dairy processing environments, raw materials and processed foods, was compiled. The set included isolates associated with recent food spoilage cases and product damages as well as isolates not linked to product spoilage. Identification of the isolates by means of Fourier-transform infrared spectroscopy and molecular methods revealed a large biodiversity of spore-formers, especially among the spoilage associated isolates. These could be assigned to 43 species, representing 11 genera, with Bacillus cereus s.l. and Bacillus licheniformis being predominant. A screening for isolates forming thermoresistant spores (TRS, surviving 100°C, 20 min) showed that about one third of the tested spore-formers was heat-resistant, with Bacillus subtilis and Geobacillus stearothermophilus being the prevalent species. Strains producing highly thermoresistant spores (HTRS, surviving 125°C, 30 min) were found among mesophilic as well as among thermophilic species. B. subtilis and Bacillus amyloliquefaciens were dominating the group of mesophilic HTRS, while Bacillus smithii and Geobacillus pallidus were dominating the group of thermophilic HTRS. Analysis of spoilage-related enzymes of the TRS isolates showed that mesophilic strains, belonging to the B. subtilis and B. cereus

  7. Characterization of single coal particle combustion within oxygen-enriched environments using high-speed OH-PLIF

    Science.gov (United States)

    Köser, J.; Becker, L. G.; Vorobiev, N.; Schiemann, M.; Scherer, V.; Böhm, B.; Dreizler, A.

    2015-12-01

    This work presents first-of-its-kind high-speed planar laser-induced fluorescence measurements of the hydroxyl radical in the boundary layer of single coal particles. Experiments were performed in a laminar flow reactor providing an oxygen-enriched exhaust gas environment at elevated temperatures. Single coal particles in a sieve fraction of 90-125 µm and a significant amount of volatiles (36 wt%) were injected along the burner's centerline. Coherent anti-Stokes Raman spectroscopy measurements were taken to characterize the gas-phase temperature. Time-resolved imaging of the OH distribution at 10 kHz allowed identifying reaction and post-flame zones and gave access to the temporal evolution of burning coal particles. During volatile combustion, a symmetric diffusion flame was observed around the particle starting from a distance of ~150 µm from the particle surface. For subsequent char combustion, this distance decreased and the highest OH signals appeared close to the particle surface.

  8. Simultaneous characterization of pancreatic stellate cells and other pancreatic components within three-dimensional tissue environment during chronic pancreatitis

    Science.gov (United States)

    Hu, Wenyan; Fu, Ling

    2013-05-01

    Pancreatic stellate cells (PSCs) and other pancreatic components that play a critical role in exocrine pancreatic diseases are generally identified separately by conventional studies, which provide indirect links between these components. Here, nonlinear optical microscopy was evaluated for simultaneous characterization of these components within a three-dimensional (3-D) tissue environment, primarily based on multichannel detection of intrinsic optical emissions and cell morphology. Fresh rat pancreatic tissues harvested at 1 day, 7 days, and 28 days after induction of chronic pancreatitis were imaged, respectively. PSCs, inflammatory cells, blood vessels, and collagen fibers were identified simultaneously. The PSCs at day 1 of chronic pancreatitis showed significant enlargement compared with those in normal pancreas (pdiseases, leading to more effective treatments.

  9. Characterization of Bacilli isolated from the confined environments of the Antarctic Concordia station and the International Space Station.

    Science.gov (United States)

    Timmery, Sophie; Hu, Xiaomin; Mahillon, Jacques

    2011-05-01

    Bacillus and related genera comprise opportunist and pathogen species that can threaten the health of a crew in confined stations required for long-term missions. In this study, 43 Bacilli from confined environments, that is, the Antarctic Concordia station and the International Space Station, were characterized in terms of virulence and plasmid exchange potentials. No specific virulence feature, such as the production of toxins or unusual antibiotic resistance, was detected. Most of the strains exhibited small or large plasmids, or both, some of which were related to the replicons of the Bacillus anthracis pXO1 and pXO2 virulence elements. One conjugative element, the capacity to mobilize and retromobilize small plasmids, was detected in a Bacillus cereus sensu lato isolate. Six out of 25 tested strains acquired foreign DNA by conjugation. Extremophilic bacteria were identified and exhibited the ability to grow at high pH and salt concentrations or at low temperatures. Finally, the clonal dispersion of an opportunist isolate was demonstrated in the Concordia station. Taken together, these results suggest that the virulence potential of the Bacillus isolates in confined environments tends to be low but genetic transfers could contribute to its capacity to spread.

  10. Production and characterization of ectoine by Marinococcus sp. ECT1 isolated from a high-salinity environment.

    Science.gov (United States)

    Wei, Yu-Hong; Yuan, Fang-Wei; Chen, Wei-Chuan; Chen, Shan-Yu

    2011-03-01

    A halophilic bacterium isolated from a salt environment in southern Taiwan was identified as a Marinococcus sp. ECT1. This bacterium could synthesize and accumulate intracellular ectoine as a compatible solute capable of resisting osmotic stress in a hyper-osmotic environment. This study also developed a semi-synthesized medium (YAMS medium), capable of facilitating the growth of this Marinococcus sp. ECT1 with 600 mg/L crude ectoine production. Moreover, Marinococcus sp. ECT1 was grown on YAMS medium containing different initial yeast extract concentrations (C(YE)) (0 to 60 g/L) to demonstrate how C(YE) affects crude ectoine production. While the maximum cell concentration was increased by 23-fold when the C(YE) was 40 g/L, the maximum crude ectoine production reached 2.5 g/L when C(YE) was 40 g/L. In addition to demonstrating the success of the fermentation strategy of ectoine in increasing the production and production yield, experimental results further demonstrated that the fermentation medium of ectoine is highly promising for commercialization. Furthermore, the molecular weight and chemical structure of ectoine were identified and characterized by FAB-MS and (1)H-NMR.

  11. Characterization of Bacilli Isolated from the Confined Environments of the Antarctic Concordia Station and the International Space Station

    Science.gov (United States)

    Timmery, Sophie; Hu, Xiaomin; Mahillon, Jacques

    2011-05-01

    Bacillus and related genera comprise opportunist and pathogen species that can threaten the health of a crew in confined stations required for long-term missions. In this study, 43 Bacilli from confined environments, that is, the Antarctic Concordia station and the International Space Station, were characterized in terms of virulence and plasmid exchange potentials. No specific virulence feature, such as the production of toxins or unusual antibiotic resistance, was detected. Most of the strains exhibited small or large plasmids, or both, some of which were related to the replicons of the Bacillus anthracis pXO1 and pXO2 virulence elements. One conjugative element, the capacity to mobilize and retromobilize small plasmids, was detected in a Bacillus cereus sensu lato isolate. Six out of 25 tested strains acquired foreign DNA by conjugation. Extremophilic bacteria were identified and exhibited the ability to grow at high pH and salt concentrations or at low temperatures. Finally, the clonal dispersion of an opportunist isolate was demonstrated in the Concordia station. Taken together, these results suggest that the virulence potential of the Bacillus isolates in confined environments tends to be low but genetic transfers could contribute to its capacity to spread.

  12. A Comparative Study of the Electrical Structure of Circum Tibetan Plateau Orogenic Belts and its Tectonic Implications

    Science.gov (United States)

    Jin, Sheng; Zhang, Letian; Wei, Wenbo; Ye, Gaofeng; Jing, Jianen; Dong, Hao; Xie, Chengliang; Yin, Yaotian

    2017-04-01

    The Tibetan Plateau, as known as "roof of the world", was created through the on-going continent-continent collision between the Indian and Eurasian plates since 55 Ma. As the process continues, the plateau is growing both vertically and horizontally. The horizontal expansion of the plateau is blocked by the Yangtze block in the east, the Tarim block in the north, and the Ordos block in the northeast, and consequently lead to the formation of the circum Tibetan plateau orogenic belts. To better understand the mechanism behind this process, we conducted a comparative study by collecting 7 magnetotelluric (MT) profiles over the margins of the Tibetan plateau, namely, the INDEPTH 100, 700 and 800 lines in the southern Tibet, the INDEPTH 4000 and 5000 lines across the Altyn Tagh fault on the northern margin of the plateau, as well as other two profiles across the Haiyuan fault and the Longmenshan fault on the northeastern and eastern margins of the plateau deployed under the framework of project SinoProbe. The electrical features of the stable blocks surrounding the Tibetan plateau are generally resistive, while crustal conductive layers are found to be wide spread within the plateau. The southern margin of the Tibetan plateau is characterized by large scale underthrust of the Indian lithosphere beneath the plateau. This intense converging process created the thrust fault system distributed along the southern margin of the Tibetan plateau over 1000 km. Crustal conductive layers discovered in southern Tibet are generally associated with the southward crustal flow that originated from the lower crust within the plateau and exhumed along the thrust belts in the Himalayas. On the eastern margin of the Tibetan plateau, the electrical structures suggest that the Yangtze block wedged into the Tibetan lithosphere and caused decoupling between the crust and upper mantel. Large scale conductors discovered beneath the Songpan-Ganze block reflect that the eastward crustal flow was

  13. Characterization of ultrafine particle number concentration and new particle formation in urban environment of Taipei, Taiwan

    Science.gov (United States)

    Cheung, H. C.; Chou, C. C.-K.; Huang, W.-R.; Tsai, C.-Y.

    2013-04-01

    An intensive aerosol characterization experiment was performed at the Taipei Aerosol and Radiation Observatory (TARO, 25.02° N, 121.53° E) in the urban area of Taipei, Taiwan during July 2012. Number concentration and size distribution of aerosol particles were measured continuously, which were accompanied by concurrent measurements of mass concentration of submicron particles, PM (d ≤ 1 μm), and photolysis rate of ozone, J(O1D). The averaged number concentrations of total (Ntotal), accumulation mode (Nacu), Aitken mode (Ntotal), and nucleation mode (Nnuc) particles were 7.6 × 103 cm-3, 1.2 × 103 cm-3, 4.4 × 103 cm-3, and 1.9 × 103 cm-3, respectively. Accordingly, the ultrafine particles (UFPs, d ≤ 100 nm) accounted for 83% of the total number concentration of particles measured in this study (10 ≤ d ≤ 429 nm), indicating the importance of UFPs to the air quality and radiation budget in Taipei and its surrounding areas. An averaged Nnuc/NOx ratio of ~60 cm-3 ppbv-1 was derived from nighttime measurements, which was suggested to be the characteristic of vehicle emissions that contributed to the "urban background" of nucleation mode particles throughout a day. On the contrary, it was found that the number concentration of nucleation mode particles was independent of NOx and could be elevated up to 10 times the "urban background" levels during daytime, suggesting a substantial amount of nucleation mode particles produced from photochemical processes. Consistency in the time series of the nucleation mode particle concentration and the proxy of H2SO4 production, UVB·SO2, for new particle formation (NPF) events showed that photo-oxidation of SO2 was responsible for the formation of new particles in our study area. Moreover, analysis upon the diameter growth rate, GR, and formation rate of nucleation mode particles, J10-25, found that the values of GR (8.5 ± 6.8 nm h-1) in Taipei were comparable to other urban areas, whereas the values of J10-25 (2.2 ± 1

  14. Holocene aeolian sediments on the NE Tibetan Plateau

    Science.gov (United States)

    Stauch, G.; Lehmkuhl, F.; Hilgers, A.; Zhao, H.

    2012-04-01

    The semiarid climate of the northeastern Tibetan Plateau supports the formation of different types of aeolian sediments and landforms during the Holocene. Aeolians silts and sands in the catchment of the Donggi Cona in an elevation above 4000m to 4800 m asl reflect variable climate conditions during that time as well as different sediment sources. Based on 51 OSL datings and catchment wide geomorphological mapping a complex pattern of long and short distance sediment transport has been reconstructed. Only few aeolian archives are preserved from the late Pleistocene in this mountain environment indicating cold and dry climate conditions which prevented a continuous accumulation. During the early Holocene a phase of increased aeolian sedimentation of sand at the slopes of the mountains has been reconstructed. The sand originated from a large alluvial fan which was highly active during the Pleistocene. In addition, a thin loess cover is preserved at a few sites in the neighboring mountains ranges. The sedimentation of the loess started around 2000 years later than the sedimentation of the sand at the foot slope. Both archives are related to an increase in precipitation at the northern margin of the Tibetan Plateau which was related to a strengthening of the Asian Monsoon during that time. The wetter climate conditions favored the development of a vegetation cover which leads to the trapping and fixation of the aeolian sediments. However, with a further strengthening of the Monsoon systems these archives subsequently eroded due to higher run off and accumulated as colluvial and fluvial deposits in the basins. These phase lasted until 6 ka. A second aeolian period started at around 3 ka with the formation new dunes in the basins. This period can be associated with dry and cold climate of the late Holocene supporting the reactivation of the sand in the area. This might be further enhanced by an increased human impact by grazing during the late Holocene and resulting

  15. Natural eco-environmental evaluation of eastern Qinghai-Tibet Plateau using RS and GIS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The impact of interbasin water transfer on environment is very significant. The affected area of the west route scheme of the South to North Water Transfer Project in China (SNWT) is located in the eastern Tibetan Plateau, where the altitude is high with frigid eco-environment. In this article,remote sensing and GIS are applied to analyze the natural environment and the natural environmentindex is established to express the natural conditions of the study area. After the natural environment index is divided into four grades and the features of each grade are analysed, some results are obtained for reference in environmental assessment of the west route of SNWT.

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

    Directory of Open Access Journals (Sweden)

    Luigi Michaud

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

  17. A step-by-step approach to improve data quality when using commercial business lists to characterize retail food environments.

    Science.gov (United States)

    Jones, Kelly K; Zenk, Shannon N; Tarlov, Elizabeth; Powell, Lisa M; Matthews, Stephen A; Horoi, Irina

    2017-01-07

    Food environment characterization in health studies often requires data on the location of food stores and restaurants. While commercial business lists are commonly used as data sources for such studies, current literature provides little guidance on how to use validation study results to make decisions on which commercial business list to use and how to maximize the accuracy of those lists. Using data from a retrospective cohort study [Weight And Veterans' Environments Study (WAVES)], we (a) explain how validity and bias information from existing validation studies (count accuracy, classification accuracy, locational accuracy, as well as potential bias by neighborhood racial/ethnic composition, economic characteristics, and urbanicity) were used to determine which commercial business listing to purchase for retail food outlet data and (b) describe the methods used to maximize the quality of the data and results of this approach. We developed data improvement methods based on existing validation studies. These methods included purchasing records from commercial business lists (InfoUSA and Dun and Bradstreet) based on store/restaurant names as well as standard industrial classification (SIC) codes, reclassifying records by store type, improving geographic accuracy of records, and deduplicating records. We examined the impact of these procedures on food outlet counts in US census tracts. After cleaning and deduplicating, our strategy resulted in a 17.5% reduction in the count of food stores that were valid from those purchased from InfoUSA and 5.6% reduction in valid counts of restaurants purchased from Dun and Bradstreet. Locational accuracy was improved for 7.5% of records by applying street addresses of subsequent years to records with post-office (PO) box addresses. In total, up to 83% of US census tracts annually experienced a change (either positive or negative) in the count of retail food outlets between the initial purchase and the final dataset. Our study

  18. The Hubble Flow of Plateau Inflation

    NARCIS (Netherlands)

    Coone, Dries; Roest, Diederik; Vennin, Vincent

    2015-01-01

    In the absence of CMB precision measurements, a Taylor expansion has often been invoked to parametrize the Hubble flow function during inflation. The standard "horizon flow" procedure implicitly relies on this assumption. However, the recent Planck results indicate a strong preference for plateau

  19. The Hubble Flow of Plateau Inflation

    NARCIS (Netherlands)

    Coone, Dries; Roest, Diederik; Vennin, Vincent

    2015-01-01

    In the absence of CMB precision measurements, a Taylor expansion has often been invoked to parametrize the Hubble flow function during inflation. The standard "horizon flow" procedure implicitly relies on this assumption. However, the recent Planck results indicate a strong preference for plateau in

  20. Ozone Minihole Found over Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Through a comprehensive analysis, researchers from the CAS Institute of Atmospheric Physics (IAP) discovered an ozone minihole, a large area with the lowest total ozone column (TOC, see figure), over the Qinghai-Tibet Plateau from Dec. 14 to 17, 2003.

  1. Construction of plateaued functions satisfying multiple criteria

    Institute of Scientific and Technical Information of China (English)

    Zhang Weiguo

    2005-01-01

    A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application could be satisfied: balancedness, high nonlinearity, correlation immunity of reasonably high order, strict avalanche criterion, non-existence of non-zero linear structures, good global avalanche characteristics, etc.

  2. Planation Surfaces on the Tibet Plateau, China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau. A denudation threshold (T), the maximum potential denudation rate for a certain type of rock, is introduced to explain the combined effects of lithology and tectonics on landform evolution. If the tectonic uplifting rate (U) is equal to or less than the threshold rate (U ≤ T), the tectonic uplifting and terrain denudation are in dynamic equilibrium, and landforms are in a steady state. The end product should be planation surfaces whether the original landforms are fiat plains or deeply dissected mountains. If U > T, uplift and denudation are not able to reach a dynamic equilibrium state. The plateau surface is mostly underlain by soft rocks, such as the Mesozoic epimetamorphic argillites and Tertiary sedimentary rocks, while the mountain ranges comprise hard rocks, such as granite, gneiss and limestone. In soft rock regions, hills are low with a relative relief of mostly less than 100m and the slopes are gentle at a gradient of <200. In contrast, hills can maintain steep slopes in hard rock regions. The Tibet Plateau has been under an equilibrium condition between tectonic uplifting and denudation except for the mountain ranges. The plateau might have reached the present altitudes before the Quaternary.

  3. FINAL FRONTIER AT HANFORD TACKLING THE CENTRAL PLATEAU

    Energy Technology Data Exchange (ETDEWEB)

    GERBER MS

    2008-03-04

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

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

    Science.gov (United States)

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

    2017-06-01

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

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

    Science.gov (United States)

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

    2016-08-01

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

  6. Late Cretaceous Arc Initiation on the Edge of an Oceanic Plateau (Southern Central America)

    Science.gov (United States)

    Buchs, D. M.; Baumgartner, P. O.; Arculus, R.

    2007-12-01

    The Caribbean Plate comprises one or several late Cretaceous oceanic plateaus imbricated between the Northern and Southern Americas. Uplifted portions of plateau(s) along plate boundaries have been recognized in many sites, including that underlying the south Central American Volcanic Arc. We provide new constraints for the role of the plateau in the evolution of this arc obtained by mapping of the uplifted forearc area between southern Costa Rica and western Panama. An oceanic plateau, accreted seamounts and arc rocks were identified, and a new tectono-stratigraphy defined. The arc basement is composed of a Coniacian oceanic plateau. In the outer margin, late Cretaceous-Eocene accreted seamounts are in contact with the plateau along tectonic mélanges and active faults. Campanian-Maastrichtian primitive arc rocks are found 40-110 km to the trench on the top of -or as dykes within- the plateau. The location of these rocks correlates to previous observations and indicates that the arc front migrated away from the trench during the late Cretaceous, potentially in response to subduction erosion or slab flattening [Lissinna et al., EGU 2006]. The first island arc lavas were deposited under sea level, over a broad area. They were quickly followed by more evolved intrusives and lavas, which were emplaced along a volcanic front during the late Cretaceous-Paleocene. Detrital and volcanic records along the Central American isthmus indicate that a continuous volcanic arc extended between eastern Panama and northern Costa Rica in this time. In southern Costa Rica (Golfito complex) and western Panama (Sona-Azuero-Coiba complex), the oceanic plateau consists mainly of pillowed and massive low Fe (tholeiitic) basalts. These rocks have a highly consistent geochemistry characterized by flat, primitive upper mantle-normalized incompatible element patterns with low Pb and high Nb-Ti contents. Primitive arc igneous samples are low-medium Fe basalts to trachyandesites found as pillow

  7. A Case Study of a Heavy Rain over the Eastern Tibetan Plateau

    Science.gov (United States)

    Chen, Q.

    2016-12-01

    A Case Study of a Heavy Rain over the Eastern Tibetan Plateau Quan-Liang Chen1, Qichao Long1, Ke Gui1, Ying Zhang2College of Atmospheric Science/Plateau Atmospheric and Environment Laboratory of Sichuan Province, Chengdu University of Information Technology, Chengdu 610225, China 2 School of Earth and Space Sciences/CAS Key Laboratory of Atmospheric Composition and Optical Radiation, University of Science and Technology of China, Hefei 230026, China Abstract: The case study can improve our understanding of precipitation over the Tibetan Plateau. This paper systematically studies a heavy rain occurred on August 5, 2014 over the eastern Tibetan Plateau (31°N 35°N, 96°E 103°E) using the orbital data of Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR). The characteristics of horizontal distribution and vertical structure of the precipitation system, convective storm top altitude and the types of rain, the mean rainfall profile and the influence of water vapor before and after the rainfall are investigated. The results suggest that the precipitation was strongly affected by the Tibetan Plateau terrain. The near-surface precipitation rate and storm top altitudes have a positive correlation. And the convection is powerful so that the convective storm top altitude can reach 16 km. Furthermore, the water vapor content has obvious changes in the upper troposphere and lower stratosphere (UTLS) area. The maximum rainfall rate appears at about 5.5 km. The deep weak convective precipitation has the largest contribution to the total precipitation. Key words: Tibetan Plateau; TRMM; precipitation; vertical structure; water vapor content; terrain

  8. The intracrustal structure beneath the Owyhee Plateau, Oregon, from receiver function analysis

    Science.gov (United States)

    Hou, T.; Chen, C.; James, D. E.; Fouch, M. J.

    2013-12-01

    The Owyhee Plateau straddles southeastern Oregon, southwestern Idaho, and northern Nevada, and is an isolated block of older, and less modified, continental lithosphere relative to bordering geologic terranes. Previous seismic studies have characterized the Owyhee Plateau as having thickened crust with low Poisson's ratio and high intracrustal S-wave velocities, and distinct, albeit thin, mantle lithosphere. Significant tectonomagmatic activity, including extension in the northern Great Basin, and intraplate volcanism is present on the margins of the Plateau, but very little volcanism takes place within the Plateau itself. The volcanism is expressed as two prominent age-progressive volcanic tracks, the Snake River Plains-Yellowstone and the High Lava Plains, both of which appear to have originated from near the Owyhee Plateau at approximately 12 Ma. Recent ambient noise tomography and scattered-wave imaging reveal the presence of irregular high velocity layering in the Owyhee mid-crust, but the extent and properties of this feature, and its role in the tectonic evolution of the Owyhee Plateau, remain elusive. In this study, we perform detailed single station Ps receiver function analysis to better constrain the discontinuity structures within the Owyhee crust. We use teleseismic waveform data recorded at 28 High Lava Plains seismic array and 12 USArray Transportable Array broadband stations from 2006 to 2009. Preliminary results show coherent signals of converted phase at ~20 km depth, indicating the presence of a positive velocity discontinuity, which may mark the upper bound of the high velocity layer imaged in previous studies. We consider and examine possible effects of seismic anisotropy on our results and are also conducting synthetic experiments to further constrain the properties of this feature.

  9. Experimental study on soil CO2 emission in the alpine grassland ecosystem on Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xianzhou; SHI Peili; LIU Yunfen; OUYANG Hua

    2005-01-01

    The Tibetan Plateau, the Roof of the World, is the highest plateau with a mean elevation of 4000 m. It is characterized by high levels of solar radiation, low air temperature and low air pressure compared to other regions around the world. The alpine grassland, a typical ecosystem in the Tibetan Plateau, is distributed across regions over the elevation of 4500 m. Few studies for carbon flux in alpine grassland on the Tibetan Plateau were conducted due to rigorous natural conditions. A study of soil respiration under alpine grassland ecosystem on the Tibetan Plateau from October 1999 to October 2001 was conducted at Pangkog County, Tibetan Plateau (31.23°N, 90.01°E, elevation 4800 m). The measurements were taken using a static closed chamber technique, usually every two weeks during the summer and at other times at monthly intervals. The obvious diurnal variation of CO2 emissions from soil with higher emission during daytime and lower emission during nighttime was discovered. Diurnal CO2 flux fluctuated from minimum at 05:00 to maximum at 14:00 in local time. Seasonal CO2 fluxes increased in summer and decreased in winter, representing a great variation of seasonal soil respiration. The mean soil CO2 fluxes in the alpine grassland ecosystem were 21.39 mgCO2 · m-2 · h-1, with an average annual amount of soil respiration of 187.46 gCO2 · m-2 · a-1. Net ecosystem productivity is also estimated, which indicated that the alpine grassland ecosystem is a carbon sink.

  10. Minimal erosion in central Tibet since the Eocene and implications for plateau development

    Science.gov (United States)

    Rohrmann, Alexander; Kapp, Paul; Reiners, Peter; Gyunn, Jerome; Carrapa, Barbara

    2010-05-01

    The growth history of the Tibetan plateau remains elusive, despite its importance for assessing mechanisms of continental lithosphere deformation and associated changes in surface elevation and climate system dynamics. In contrast to the actively growing plateau margins, the interior of the modern Tibetan plateau is characterized by extremely low erosion rates. We present the first apatite (U-Th)/He low-temperature thermochronologic results from samples collected away from late Cenozoic rifts in the Lhasa and Qiangtang terranes of central Tibet. These data are complemented by apatite fission-track and K-feldspar 40Ar/39Ar results, to construct continuous cooling histories. The data indicate that in most places, low erosion rates (< ~0.05 mm/yr) were established by the time India collided with Asia ~50 Myr ago, following earlier episodes of more rapid exhumation that correspond in time with documented Cretaceous - Eocene thrust belt activity. Findings of large-magnitude (≥50%) upper-crustal shortening and substantial exhumation prior to 50 Myr ago, followed by minimal subsequent denudation, support the establishment of a proto-plateau in central Tibet prior to the Indo-Asian collision. Collectively, the exhumation history of central Tibet, away from the influence of late Cenozoic rifts, contrasts sharply with that of the Lhasa region in the southern Lhasa terrane and near the modern margins of the plateau which show prominent erosional signatures of the Indo-Asian collision. Any viable model of plateau development must explain these prominent spatial variations in exhumation history as well as the lack of a corresponding expression in the modern topography.

  11. Some practical notes on the land surface modeling in the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    K. Yang

    2009-05-01

    Full Text Available The Tibetan Plateau is a key region of land-atmosphere interactions, as it provides an elevated heat source to the middle-troposphere. The Plateau surfaces are typically characterized by alpine meadows and grasslands in the central and eastern part while by alpine deserts in the western part. This study evaluates performance of three state-of-the-art land surface models (LSMs for the Plateau typical land surfaces. The LSMs of interest are SiB2 (the Simple Biosphere, CoLM (Common Land Model, and Noah. They are run at typical alpine meadow sites in the central Plateau and typical alpine desert sites in the western Plateau.

    The identified key processes and modeling issues are as follows. First, soil stratification is a typical phenomenon beneath the alpine meadows, with dense roots and soil organic matters within the topsoil, and it controls the profile of soil moisture in the central and eastern Plateau; all models, when using default parameters, significantly under-estimate the soil moisture within the topsoil. Second, a soil surface resistance controls the surface evaporation from the alpine deserts but it has not been reasonably modeled in LSMs; an advanced scheme for soil water flow is implemented in a LSM, based on which the soil resistance is determined from soil water content and meteorological conditions. Third, an excess resistance controls sensible heat fluxes from dry bare-soil or sparsely vegetated surfaces, and all LSMs significantly under-predict the ground-air temperature gradient, which would result in higher net radiation, lower soil heat fluxes and thus higher sensible heat fluxes in the models. A parameterization scheme for this resistance has been shown to be effective to remove these biases.

  12. Petrology and Bulk Chemistry of Modern Bed Load Sediments From Rivers Draining the Eastern Tibetan Plateau

    Science.gov (United States)

    Borges, J. B.

    2003-12-01

    We studied river bed load petrology and bulk sediment chemistry of the headwaters of the Changjiang, Huang He and Red rivers in China and Vietnam. These rivers drain the eastern and southeastern parts of the Tibetan Plateau which includes part of the Indian-Eurasian suture zone. The eastern Tibetan Plateau is dominated by marine sedimentary rocks with a few scattered intrusive igneous outcrops, while the suture zone is characterized by a mixture of high-grade metamorphic, ultramafic, granitic, volcanic arc and marine sedimentary rocks. The arithmetic average for Qt: Ft: Rft along the suture zone varies from 56:2:42 along the Red River Fault (RRF) zone to 38:6:56 in the interior of the continent, while sands from rivers draining the plateau average 32:8:60. The sands analyzed in this study are relatively immature compared to most data available from most rivers in the tropics. The average Chemical Index of Alteration (CIA) for samples from the RRF suture zone (0.62) is similar to that of rivers draining other tropical regions like the Niger, Chao Phraya, Mekong, Ganges, Amazon and Brahmaputra. The CIA values from the RRF zone are also significantly different from the rest of the suture zone (0.36) and the plateau area (0.38). The difference can be attributed to the combined effect of relief and precipitation. The RRF lies in the Red River drainage and receives ˜1820 mm of precipitation annually, while the plateau area averages ˜620 mm annually. In the case of the Red River drainage, the relief combined with higher humidity can increase physical weathering and reduce the residence time of sediment in the river drainage, therefore, continuously replacing the sediment transported out of the drainage by freshly weathered immature materials. In the plateau area, lower precipitation and runoff may limit sediment transport and chemical weathering leading to sediment immaturity.

  13. Soil erosion and management on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Loess Plateau is well known to the world for its intense soil erosion. The root cause for river sedimentation of Yellow River (Huanghe) and its resultant "hanging river" in certain section is soil and water loss on the Loess Plateau. The Loess Plateau has a long cultivation history, hence population growth, vegetation degeneration and plugging constitute the chief reason for serious soil and water loss on Loess Plateau. This paper analyses several successful cases and failures in soil conservation, presents practical soil conservation technique and related benefit analysis, and discusses some effective methods adopted in China in soil erosion control, research directions and future perspectives on Loess Plateau.

  14. 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.

  15. Localized environment characterization device

    KAUST Repository

    Alzain, Hashim

    2016-07-21

    Various apparatuses and methods are provided for measuring the likely environmental impact of a particular geographic location on power generation properties of potential solar installations at the particular location. In an example embodiment of one such apparatus, a measurement device is provided. The measurement device includes a base portion comprising a base frame element disposed on a plurality of supporting legs, and a top panel comprising a series of connected members and one or more measurement modules whose planar dimensions are defined by the series of connected members. The top panel is connected to the base portion by a joint such that the top panel can rotate about the joint, and a panel support element is configured to fasten the top panel immovably at a desired degree of rotation in relation to the base portion.

  16. Molecular Characterization and Expression Analysis of Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Protein-1 Genes in Qinghai-Tibet Plateau and Lowland

    Directory of Open Access Journals (Sweden)

    Ya-bing Chen

    2015-01-01

    Full Text Available Insulin-like growth factor-1 (IGF-1 and insulin-like growth factor binding protein-1 (IGFBP-1 play a pivotal role in regulating cellular hypoxic response. In this study, we cloned and characterized the genes encoding IGF-1 and IGFBP-1 to improve the current knowledge on their roles in highland Bos grunniens (Yak. We also compared their expression levels in the liver and kidney tissues between yaks and lowland cattle. We obtained full-length 465 bp IGF-1 and 792 bp IGFBP-1, encoding 154 amino acids (AA IGF-1, and 263 AA IGFBP-1 protein, respectively using reverse transcriptase-polyerase chain reaction (RT-PCR technology. Analysis of their corresponding amino acid sequences showed a high identity between B. grunniens and lowland mammals. Moreover, the two genes were proved to be widely distributed in the examined tissues through expression pattern analysis. Real-time PCR results revealed that IGF-1 expression was higher in the liver and kidney tissues in B. grunniens than in Bos taurus (p<0.05. The IGFBP-1 gene was expressed at a higher level in the liver (p<0.05 of B. taurus than B. grunniens, but it has a similar expression level in the kidneys of the two species. These results indicated that upregulated IGF-1 and downregulated IGFBP-1 are associated with hypoxia adaptive response in B. grunniens.

  17. Palynological evidence for late Miocene stepwise aridification on the northeastern Tibetan Plateau

    Science.gov (United States)

    Liu, Jia; Li, Ji Jun; Song, Chun Hui; Yu, Hao; Jiang Peng, Ting; Chuang Hui, Zheng; Ye, Xi Yan

    2016-07-01

    Holding a climatically and geologically key position both regionally and globally, the northeastern Tibetan Plateau provides a natural laboratory for illustrating the interactions between tectonic activity and the evolution of the Asian interior aridification. Determining when and how the late Miocene climate evolved on the northeastern Tibetan Plateau may help us better understand the relationships among tectonic uplift, global cooling and ecosystem evolution. Previous paleoenvironmental research has focused on the western Longzhong Basin. Late Miocene aridification data derived from pollen now require corroborative evidence from the eastern Longzhong Basin. Here, we present a late Miocene pollen record from the Tianshui Basin in the eastern Longzhong Basin. Our results show that a general trend toward dry climate was superimposed by stepwise aridification: a temperate forest with a rather humid climate existed in the basin between 11.4 and 10.1 Ma, followed by a temperate open forest environment with a less humid climate between 10.1 and 7.4 Ma, then giving way to an open temperate forest-steppe environment with a relatively arid climate between 7.4 and 6.4 Ma. The vegetation succession demonstrates that the aridification of the Asian interior occurred after ˜ 7-8 Ma, which is confirmed by other evidence from Asia. Furthermore, the aridification trend on the northeastern Tibetan Plateau parallels the global cooling of the late Miocene; the stepwise vegetation succession is consistent with the major uplift of the northeastern Tibetan Plateau during this time. These integrated environmental proxies indicate that the long-term global cooling and the Tibetan Plateau uplift caused the late Miocene aridification of the Asian interior.

  18. Spatial distribution and controlling factors of stable isotopes in meteoric waters on the Tibetan Plateau: Implications for paleoelevation reconstruction

    Science.gov (United States)

    Li, Lin; Garzione, Carmala N.

    2017-02-01

    Debates persist about the interpretations of stable isotope based proxies for the surface uplift of the central-northern Tibetan Plateau. These disputes arise from the uncertain relationship between elevation and the δ18 O values of meteoric waters, based on modern patterns of isotopes in precipitation and surface waters. We present a large river water data set (1,340 samples) covering most parts of the Tibetan Plateau to characterize the spatial variability and controlling factors of their isotopic compositions. Compared with the amount-weighted mean annual oxygen isotopic values of precipitation, we conclude that river water is a good substitute for isotopic studies of precipitation in the high flat (e.g., elevation >3,300 m) interior of the Tibetan Plateau in the mean annual timescale. We construct, for the first time based on field data, contour maps of isotopic variations of meteoric waters (δ18 O, δD and d-excess) on the Tibetan Plateau. In the marginal mountainous regions of the Plateau, especially the southern through eastern margins, the δ18 O and δD values of river waters decrease with increasing mean catchment elevation, which can be modeled as a Rayleigh distillation process. However, in the interior of the Plateau, northward increasing trends in δ18 O and δD values are pronounced and present robust linear relations; d-excess values are lower than the marginal regions and exhibit distinct contrasts between the eastern (8 ‰- 12 ‰) and western (<8‰) Plateau. We suggest that these isotopic features of river waters in the interior of the Tibetan Plateau result from the combined effects of: 1) mixing of different moisture sources transported by the South Asian monsoon and Westerly winds; 2) contribution of moisture from recycled surface water; and 3) sub-cloud evaporation. We further provide a sub-cloud evaporation modified Rayleigh distillation and mixing model to simulate the isotopic variations in the western Plateau. Results of this work

  19. Zn/ZnO core/shell nanoparticles synthesized by laser ablation in aqueous environment: Optical and structural characterizations

    Indian Academy of Sciences (India)

    S C Singh; R K Swarnkar; R Gopal

    2010-02-01

    Zn/ZnO core/shell nanoparticles are synthesized by pulsed laser ablation (PLA) of Zn metal plate in the aqueous environment of sodium dodacyl sulfate (SDS). Solution of nanoparticles is found stable in the colloidal form for a long time, and is characterized by UV-visible absorption, transmission electron microscopy (TEM), photoluminescence (PL) and Raman spectroscopic techniques. UV-visible absorption spectrum has four peaks at 231, 275, 356, and 520 nm, which provides primary information about the synthesis of core-shell and elongated nanoparticles. TEM micrographs reveal that synthesized nanoparticles are monodispersed with three different average sizes and size distributions. Colloidal solution of nanoparticles has significant absorption in the green region, therefore, it absorbs 514.7 nm light of Ar+ laser and emits in the blue region centred at 350 and 375 nm, violet at 457 nm and green at 550 nm regions. Raman shift is observed at 300 cm-1 with PL spectrum, which corresponds to ${}^{3}$2N and 3L mode of vibrations of ZnO shell layer. Synthesis mechanism of Zn/ZnO core/shell nanoparticles is discussed.

  20. Novel cross linked guar gum-g-poly(acrylate) porous superabsorbent hydrogels: Characterization and swelling behaviour in different environments.

    Science.gov (United States)

    Chandrika, Ksv Poorna; Singh, Anupama; Rathore, Abhishek; Kumar, Anil

    2016-09-20

    A new series of eco-friendly cross linked guar gum-g-poly(acrylate) porous superabsorbent hydrogels was prepared by in situ grafting polymerization and cross-linking on to a natural guar gum employing N,N-methylene bis acrylamide as cross linker. Morphological and structural characterization of the prepared hydrogels (SPHs) done by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and solid state C(13) NMR spectroscopy confirmed formation of porous grafted and crosslinked hydrogel structure. Increase in cross linker concentration in the feed mass exhibited decrease in porosity and increase in density of the hydrogels. Swelling of an optimized hydrogel (SPH) in response to external stimuli namely, salt solutions, fertilizer solutions, temperature, and pH exhibited high swelling ratios in various environments. Swelling rate of the SPH was faster than the corresponding nonporous superabsorbent hydrogel. The prepared hydrogels can serve as excellent carriers of pesticides, fertilizers and agriculturally important microbes. Biocontrol formulations based on a representative SPH exhibited excellent shelf-life characteristics and bioefficacy against phytopathogenic fungus Pythium aphanidermatum.

  1. Actinobacteria phylogenomics, selective isolation from an iron oligotrophic environment and siderophore functional characterization, unveil new desferrioxamine traits.

    Science.gov (United States)

    Cruz-Morales, Pablo; Ramos-Aboites, Hilda E; Licona-Cassani, Cuauhtémoc; Selem-Mójica, Nelly; Mejía-Ponce, Paulina M; Souza-Saldívar, Valeria; Barona-Gómez, Francisco

    2017-09-01

    Desferrioxamines are hydroxamate siderophores widely conserved in both aquatic and soil-dwelling Actinobacteria. While the genetic and enzymatic bases of siderophore biosynthesis and their transport in model families of this phylum are well understood, evolutionary studies are lacking. Here, we perform a comprehensive desferrioxamine-centric (des genes) phylogenomic analysis, which includes the genomes of six novel strains isolated from an iron and phosphorous depleted oasis in the Chihuahuan desert of Mexico. Our analyses reveal previously unnoticed desferrioxamine evolutionary patterns, involving both biosynthetic and transport genes, likely to be related to desferrioxamines chemical diversity. The identified patterns were used to postulate experimentally testable hypotheses after phenotypic characterization, including profiling of siderophores production and growth stimulation of co-cultures under iron deficiency. Based in our results, we propose a novel des gene, which we term desG, as responsible for incorporation of phenylacetyl moieties during biosynthesis of previously reported arylated desferrioxamines. Moreover, a genomic-based classification of the siderophore-binding proteins responsible for specific and generalist siderophore assimilation is postulated. This report provides a much-needed evolutionary framework, with specific insights supported by experimental data, to direct the future ecological and functional analysis of desferrioxamines in the environment. © FEMS 2017.

  2. Molecular characterization ofAcidithiobacillus ferrooxidans strains isolated from different environments by three PCR-based methods

    Institute of Scientific and Technical Information of China (English)

    吴学玲; 刘莉莉; 张真真; 刘新星; 邓凡凡

    2015-01-01

    PCR-based DNA fingerprinting, REP-PCR (repetitive element PCR), RAPD (randomly amplified polymorphic DNA) and 16S rDNA sequence analyses were used to characterize 23Acidithiobacillus ferrooxidansstrains isolated from different environments. (GTG)5 and BOXA1R primer were selected for REP-PCR. Twenty arbitrary primers were used for RAPD to acquire DNA profiles fromA. ferrooxidans. Both RAPD and REP-PCR produce complex banding patterns and show good discriminatory ability in differentiating closely related strains ofA. ferrooxidans. The strains are clustered into 4 or 5 major groups and reveal genomic diversity using (GTG)5-PCR, BOX-PCR and RAPD analysis. Phylogenetic tree based on 16S rDNA sequences of 23 strains and related strains shows that they are clustered into two distinct groups. Twelve strains are highly related to a newAcidithiobacillus namedAcidithiobacillus ferrivorans. The results indicate that PCR-based methods are effective in revealing genetic diversity among A. ferrooxidans.

  3. Characterization of local hydrophobicity on sapphire (0001) surfaces in aqueous environment by colloidal probe atomic force microscopy

    Science.gov (United States)

    Wada, Tomoya; Yamazaki, Kenji; Isono, Toshinari; Ogino, Toshio

    2017-02-01

    Sapphire (0001) surfaces exhibit a phase-separation into hydrophobic and hydrophilic domains upon high-temperature annealing, which were previously distinguished by the thickness of adsorbed water layers in air using atomic force microscopy (AFM). To characterize their local surface hydrophobicity in aqueous environment, we used AFM equipped with a colloidal probe and measured the local adhesive force between each sapphire domain and a hydrophilic SiO2 probe surface, or a hydrophobic polystyrene one. Two data acquisition modes for statistical analyses were used: one is force measurements at different positions of the surface and the other repeated measurement at a fixed position. We found that adhesive force measurements using the polystyrene probe allow us to distinctly separate the hydrophilic and hydrophobic domains. The dispersion in the force measurement data at different positions of the surface is larger than that in the repeated measurements at a fixed position. It indicates that the adhesive force measurement is repeatable although their data dispersion for the measurement positions is relatively large. From these results, we can conclude that the hydrophilic and hydrophobic domains on the sapphire (0001) surfaces are distinguished by a difference in their hydration degrees.

  4. Development of an active detector for the characterization of the late-time radiation environment from a reactor pulse

    Energy Technology Data Exchange (ETDEWEB)

    Luker, S.M. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 1146, P.O. Box 5800, Albuquerque, NM 87185-1146 (United States); Griffin, P.J. [Nuclear Facility Operations, Sandia National Laboratories, Mail Stop 0614, P.O. Box 5800, Albuquerque, NM 87185-1146 (United States); Kolb, N.R. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 0982, P.O. Box 5800, Albuquerque, NM 87185-0982 (United States); Naranjo, G.N. [Advanced Nuclear Concepts, Sandia National Laboratories, Mail Stop 1143, P.O. Box 5800, Albuquerque, NM 87185-1143 (United States); Suo-Anttila, A.J. [Computational Engineering Analysis LLC, Albuquerque, NM 87111 (United States)

    2011-07-01

    Document available in abstract form only, full text of document follows: This paper discusses the use of a commercially available {sup 235}U fission chamber, with a matching compensating ion chamber, originally sold as a single-ended detector with the signal conducted over the shield of a coaxial cable. The authors designed an aluminum housing that isolates the two detectors and converts the signals to full differential mode as a noise-reduction technique. The signals are processed using the switched resistor technique to extend the signal range to longer times from the peak of the pulse [Luker, S. M., Griffin, P. J., King, D. B., and Suo-Anttila, A. J., 'Improved Diagnostics for Analysis of a Reactor Pulse Radiation Environment,' 13. International Symposium on Reactor Dosimetry, Akersloot, Netherlands, May 25, 2008, pp. 4-6.]. The newly configured fission chamber assembly has been used at the annular core research reactor at Sandia National Laboratories to provide a high-fidelity characterization of the neutron time profile from a pulsed operation. (authors)

  5. Magnetotelluric sounding results in eastern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    马晓冰; 孔祥儒; 刘宏兵; 闫永利

    2001-01-01

    The results of Zayu-Qingshuihe MT sounding profile carried out in eastern Tibetan Plateau are presented in this paper. Using 2-D RRI method, the resistivity distribution with depth is obtained along the profile. It is featured by the resistivity zones in the horizontal direction and layers in the vertical direction. The Bangong-Nujiang suture zone and Jinshajiang suture zone are both important electrical conductivity-separating zones in the plateau, and the former is a zone with relatively low resistivity while the latter is an electrical conductivity gradient zone. The highly electrical conductive bodies in the mid and lower crust of northern Qiangtang and Bayan Har Terrain might be caused by regional melting due to shear heating during the process of subduction in tectonic evolution.

  6. [Coupling coordinated development of ecological-economic system in Loess Plateau].

    Science.gov (United States)

    Zhang, Qing-Feng; Wu, Fa-Qi; Wang, Li; Wang, Jian

    2011-06-01

    Based on system theory, a coupling coordinated development model of ecological-economic system in Loess Plateau was established, and the evaluation criteria and basic types of the coordinated development of the ecological-economic system were proposed. The county-level coupling coordinated development of the ecological-economic system was also discussed, based on the local characteristics. The interactions between the ecological and economic systems in Loess Plateau could be divided into four stages, i.e., seriously disordered development stage, mild-disordered development stage, low-level coordinated development stage, and high level well-coordinated development stage. At each stage, there existed a cyclic process of profit and loss-antagonist-running-dominant-synchronous development. The coupling development degree of the ecological-economic system in Loess Plateau was overall at a lower level, being about 62.7% of the counties at serious disorder, 30.1% of the counties at mild disorder, and 7.1% of the counties at low but coordinated level. The coupling development degree based on the model established in this study could better reflect the current social-economic and ecological environment situations, especially the status of coordination. To fully understand the coupling of ecological-economic system and to adopt appropriate development mode would be of significance to promote the county-level coordinated development in Loess Plateau.

  7. Convergent, parallel and correlated evolution of trophic morphologies in the subfamily schizothoracinae from the Qinghai-Tibetan plateau.

    Science.gov (United States)

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

    2012-01-01

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

  8. Structure and multiphased evolution of the Demerara plateau (offshore Suriname, French Guiana)

    Science.gov (United States)

    Mercier de Lépinay, Marion; Basile, Christophe; Loncke, Lies; Maillard, Agnès; Grall, Céline; Roest, Walter R.; de Clarens, Philippe

    2014-05-01

    Offshore Suriname and French Guiana, the Demerara plateau is a continental indentation at the intersection of two oceanic domains : the Jurassic Central Atlantic and the Early Cretaceous Equatorial Atlantic. Its three borders are passive margins. The northern one is a transform margin, the two others are rifted margins, thinned during Trias/Jurassic (westward), and a second time during Early Cretaceous (eastward). The main stratigraphic feature of the Demerara plateau is the major upper Albian angular erosive unconformity, synchronous to the Equatorial Atlantic break-up. We here focus on the sedimentary records observed below the upper Albian discordance, where seismic data show more than 13 km of layered units. The aim of this study is to give new insights about the evolution of the Demerara plateau during Mesozoic times, in order to constrain vertical displacements especially in relation with the transform margin. We use mostly structural interpretation of industrial and academic seismic lines (GUYAPLAC, 2003 and IGUANES, 2013), calibrated by industrial wells down to Berriasian times. It allows us to propose structural maps and regional interpretative cross-sections of the plateau and its three borders. On seismic lines, undated prominent seismic units are characterized by important thickness variations, and weak continuity of intern reflectors. They thicken westward (toward the Central Atlantic ocean). One possible interpretation is to relate these units to trias/jurassic syn-rift sediments deposition associated to a continentward dipping fault. But the complex is formed by a repetition of several layer fans. Hence one alternative interpretation would be that these units were seaward dipping reflectors stacked during Trias/Jurassic rifting, suggesting that the role of magmatism should have been predominant during the first phase of the plateau formation. All the sediments of the plateau, including Aptian sediments, are deformed with numerous structures (strike

  9. Quantifying sources, transport, deposition, and radiative forcing of black carbon over the Himalayas and Tibetan Plateau

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Rudong; Wang, Hailong; Qian, Yun; Rasch, Philip J.; Easter, Richard C.; Ma, Po-Lun; Singh, Balwinder; Huang, Jianping; Fu, Qiang

    2015-01-01

    Black carbon (BC)particles over the Himalayas and Tibetan Plateau (HTP), both airborne and those deposited on snow, have been shown to affect snowmelt and glacier retreat. Since BC over the HTP may originate from a variety of geographical regions and emission sectors, it is essential to quantify the source-receptor relationships of BC in order to understand the contributions of natural and anthropogenic emissions and provide guidance for potential mitigation actions. In this study, we use the Community Atmosphere Model version 5 (CAM5) with a newly developed source tagging technique, nudged towards the MERRA meteorological reanalysis, to characterize the fate of BC particles emitted from various geographical regions and sectors. Evaluated against observations over the HTP and surrounding regions, the model simulation shows a good agreement in the seasonal variation of the near-surface airborne BC concentrations, providing confidence to use this modeling framework for characterizing BC source- receptor relationships. Our analysis shows that the relative contributions from different geographical regions and source sectors depend on seasons and the locations in the HTP. The largest contribution to annual mean BC burden and surface deposition in the entire HTP region is from biofuel and biomass (BB) emissions in South Asia, followed by fossil fuel (FF) emissions from South Asia, then FF from East Asia. The same roles hold for all the seasonal means except for the summer when East Asia FF becomes more important. For finer receptor regions of interest, South Asia BB and FF have the largest impact on BC in Himalayas and Central Tibetan Plateau, while East Asia FF and BB contribute the most to Northeast Plateau in all seasons and Southeast Plateau in the summer. Central Asia and Middle East FF emissions have relatively more important contributions to BC reaching Northwest Plateau, especially in the summer. Although the HTP local emissions only contribute about 10% of BC in

  10. The Influence of Urbanization on Air Temperature in Nagqu County, Tibetan Plateau

    Science.gov (United States)

    Lin, Yun; Hu, Zeyong

    2016-04-01

    According to meteorological data obtained at Nagqu meteorological station, which is in the Nagqu County (NQ) and at site BJ of Nagqu Station of Plateau Climate and Environment (BJ), which is outside Nagqu County, the differences in air temperature (Ta) variations at NQ and BJ from 2001 to 2014 were compared and analyzed with respect of urbanization. Both the natural processes and human activities that could lead to the differences in Ta between NQ and BJ were studied in this study. Natural processes are characterized by meteorological variables such as wind, precipitation, sunshine hours, vapor pressure and the human activities are characterized by urbanization index. The results show that the annual mean temperature (Ta_mean) and annual mean minimum temperature (Ta_min) at NQ are higher than those at BJ from 2001 to 2014. But the annual mean maximum temperature (Ta_max) at NQ is smaller than that at BJ. The urbanization of Nagqu County has increased in the past fifteen years and reached to 27.24% in 2014. There are good agreements between Ta_max and natural factors including sunshine hours and water vapor pressure at NQ and BJ. And Ta_min has a positive relationship with human activities such as the GDP and population of Nagqu County. But the relationship between Ta_min with human activities at NQ is stronger than that at BJ. This is because BJ is a field site and the strength of human activity is weak. The Natural processes has a stronger influence on the variation of Ta_min at BJ than human activities do.

  11. The crustal composition of the Falkland Plateau

    Science.gov (United States)

    Klemt, Claudia; Jokat, Wilfried

    2015-04-01

    The Falkland Islands are situated in the South Atlantic Ocean 500 km east of Patagonia, South America. The islands are part of the Falkland Plateau, which stretches eastward for more than 1500 km. A bathymetric high, the Maurice Ewing Bank, terminates the plateau in the east. Until Late Jurassic the Falkland Islands were part of Gondwana and were located adjacent to the east coast of South Africa. While the Falkland Islands and Maurice Ewing Bank are proved to be of continental composition, the nature and structure of the Falkland Plateau's basement in between is debatable. The first crustal model derived from sonobuoy data contradicts an only recently published 3D-gravity model. To enhance the understanding of Gondwana break-up considering timing, geometry and amount of volcanism, further knowledge about the structure and thickness of the crust is inevitable. During the ANT-XXIX/5 Polarstern cruise seismic refraction measurements were conducted using Ocean Bottom Seismometers (OBS) and Reftek land stations onshore of East Falkland. The OBS were deployed at 78 locations along an approximately 1500 km east-west stretching profile. For the western transect a P-wave velocity model is calculated using 2D-raytracing techniques. The results are presented in combination with potential field data showing the extension of the Falkland Islands basement, the continent-ocean transition zone and the crustal structure of the plateau. On the Falkland Plateau Basin sediment thickness is about 6 km with velocities ranging from 1.7 to 4.1 km/s in the upper part and about 4.7 km/s above basement. The crust is of oceanic composition with an igneous section that is considerably thicker than average oceanic crust (up to 17 km). The velocity structure in the upper crustal part is typical for layer 2 with a velocity gradient ranging from 5.4 km/s to 6.5 km/s and thicknesses between 1.5 km and 4 km. Layer 3 is about 14 km thick with a velocity gradient from 6.6 km/s to 7.6 km/s, which is

  12. Microfacies analysis of foraminifera rich sedimentary rocks from the Desert Plateau, central Egypt.

    Science.gov (United States)

    Karnitschar, C.; Briguglio, A.; Hohenegger, J.

    2012-04-01

    Microfacies analysis on some samples from the Thebes Group have been carried on by means of thin sections. The study area is included in the Libyan Desert Plateau (central Egypt) at following coordinates N27° 36'30.58" E29° 44'58.34", near the biggest dune of Egypt, the Ghard Abu Muharik. Because of the round shape of the rocks and the desert patina on the surface they could easily be classified as the so called "Melonstones", which are located more southwards and mainly composed by stromatolites. On the contrary, the investigated samples show a completely different fauna and therefore have been separated from the "Melonstones". Even if shape and size are very similar and the desert patina covers all surfaces the same way the differences are impressive. To investigate the samples, two thin-sections have been prepared and analyzed at the microscope. The observed fauna is composed by: agglutinated benthic foraminifera (e.g., Dictyoconus egypticus), complex larger miliolids (e.g., Pseudolacazina cf. danatae, Fabularia sp.), alveolinids (Alveolina vredenburgi), green algae (Dasycladaceae), echinoids and corals. Because of the presence of symbionts bearing larger benthic foraminifera, which need light to feed photosymbionts, the rock was formed in a shallow water environment. With the abundant rock-building benthic foraminifera and calcareous algae the limestone shows a tendency to the packstone/wackestone facies. Based on the presence of Alveolina vredenburgi, the age of the samples can be estimate as lowermost Eocene belonging to the shallow benthic zone 5 (sensu Serra-Kiel et al., 1998). According the obtained data on stratigraphy and palaeoecology, a partial palaeoenvironmental reconstruction is possible for the Libyan Desert Plateau where outcrops are largely missing. Because of the round shape of the samples and the patina which covers them all around it can be assumed that they have been transported from longer distance. According to the geological map of the

  13. Structural and Mechanical Characterization of Nanocrystalline Tungsten and Tungsten-Based Alloy Thin Films for Extreme Environment Applications

    Science.gov (United States)

    Martinez, Gustavo

    Extreme environments associated with nuclear applications often results in degradation of the physical, mechanical and thermo-mechanical properties of the materials. Tungsten (W) exhibits unique physical and mechanical properties, which makes tungsten a good candidate for nuclear applications; however, intrinsic W exhibits low fracture toughness at all temperatures in addition to a high ductile to brittle transition. In the present work, nanocrystalline W, W-Y and W-Mo alloys were nanoengineered for nuclear applications. Nanocrystalline tungsten coatings with a thickness of 1 microm were deposited onto Silicon (100) and Sapphire (C-plane) using RF and DC sputtering techniques under various growth conditions. Yttrium content in W-Y alloys has been varied to enhance the irradiation tolerance under optimum concentration. The W, W-Y coatings were characterized to understand the structure and morphology and to establish a mapping of conditions to obtain phase and size controlled materials. The samples were then subjected to depth-controlled irradiation by neutrons and Au3+ ions. Solid solution strengthening was achieved by doping molybdenum (Mo) solute atoms to W matrix under varied sputtering pressures and temperatures with the intention of creating interstitial point defects in the crystals that impede dislocation motion, increasing the hardness and young modulus of the material. The effect of PAr (3-19 mTorr) was also investigated and associated microstructure are significant on the mechanical characteristics; the hardness (H) and modulus of elasticity (Er) of the nc W-Mo thin films were higher at lower pressures but decreases continuously with increasing PAr. Using nano-indentation and nano-scratch technique, mechanical characterization testing was performed before and after irradiation. The structure, mechanics and irradiation stability of the W and W-Y coatings will be presented and discussed to demonstrate that Y-addition coupled with nano-scale features

  14. Analysis on geological environment and disaster types in the loess plateau---A case study of Huanxian county in Gansu province%黄土高原区地质环境特征及灾害发育类型分析--以甘肃省环县为例

    Institute of Scientific and Technical Information of China (English)

    郭瑞; 丁宏伟; 包骊军; 彭杨宏; 王永红

    2016-01-01

    Combined with instance on landslide evaluation in Huanxian county , Gansu province , this paper summed up the developmental type of geological disasters and analyzed the geological environment char -acteristics and causes of geological disasters in the Loess Plateau .The research results show that it has com-plex topography and drought , the new tectonic activity is strong , the majority of the area is covered by loess in this area.The groundwater types are mainly loose rock type pore water and fissure water .The soil type are generally based on general soil (sandy loam, loam clay, etc) and special soil(loess).The distribution of geo-logical hazards is not only universal but also uneven , and it is distributed along the banks of the river valley , but the distribution is sparse , in medium altitude mountain area .The main types of geological disasters are the landslide , mudslides , avalanches and unstable slopes .The main factors forming geological disasters have to-pography , soil types and geological structure .The groundwater and vegetation are secondary factors that cause the formation of geological disasters .It is a predisposing factor ( inducing rainfall , earthquake and human activ-ity) that cause geological disasters .The landslide is more likely to be affected by slope gradient .The land-slide is mostly likely to erupt at 20 °~50 °slope interval .The collapse occurs mostly in relatively high and steep slope ( slope is greater than 70 °) .The mud flow mostly develops in the valley , specifically , in the basin area of 0.1~5.0 km2 , with a gully slope angle of being 25°~45°, and the main channel longitudinal gradi-ent being within 10%~40%.%结合甘肃省环县地质灾害详细调查实例,总结了黄土高原区地质灾害的发育类型,分析了区域内地质环境特征及地质灾害成因。得出以下结论:区域内地形地貌条件复杂,新构造活动强烈,广大地区为黄土所覆盖,地下水类型主要为松散岩

  15. Synthesis and characterization of divalent manganese, iron, and cobalt complexes in tripodal phenolate/N-heterocyclic carbene ligand environments.

    Science.gov (United States)

    Käß, Martina; Hohenberger, Johannes; Adelhardt, Mario; Zolnhofer, Eva M; Mossin, Susanne; Heinemann, Frank W; Sutter, Jörg; Meyer, Karsten

    2014-03-03

    Two novel tripodal ligands, (BIMPN(Mes,Ad,Me))(-) and (MIMPN(Mes,Ad,Me))(2-), combining two types of donor atoms, namely, NHC and phenolate donors, were synthesized to complete the series of N-anchored ligands, ranging from chelating species with tris(carbene) to tris(phenolate) chelating arms. The complete ligand series offers a convenient way of tuning the electronic and steric environment around the metal center, thus, allowing for control of the complex's reactivity. This series of divalent complexes of Mn, Fe, and Co was synthesized and characterized by (1)H NMR, IR, and UV/vis spectroscopy as well as by single-crystal X-ray diffraction studies. Variable-temperature SQUID magnetization measurements in the range from 2 to 300 K confirmed high-spin ground states for all divalent complexes and revealed a trend of increasing zero-field splitting |D| from Mn(II), to Fe(II), to Co(II) complexes. Zero-field (57)Fe Mössbauer spectroscopy of the Fe(II) complexes 3, 4, 8, and 11 shows isomer shifts δ that increase gradually as carbenes are substituted for phenolates in the series of ligands. From the single-crystal structure determinations of the complexes, the different steric demand of the ligands is evident. Particularly, the molecular structure of 1-in which a pyridine molecule is situated next to the Mn-Cl bond-and those of azide complexes 2, 4, and 6 demonstrate the flexibility of these mixed-ligand derivatives, which, in contrast to the corresponding symmetrical TIMEN(R) ligands, allow for side access of, e.g., organic substrates, to the reactive metal center.

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

    Directory of Open Access Journals (Sweden)

    Nikić Zoran

    2010-01-01

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

  17. The geological structure background and the crustal structure in the northeastern margin of the Qinghai-Tibetan plateau

    Institute of Scientific and Technical Information of China (English)

    ZHOU Min-du; Lü Tai-yi; ZHANG Yuan-sheng; RUAN Ai-guo

    2000-01-01

    The geological structure background, the crustal structure and the shape of Moho in the northeastern margin of the Qinghai-Tibetan plateau are studied. Based on artificial seismic sounding profile as well as geological data. The main results are summarized as follows: j The geotectonic subdivisions and the characteristics of main deep and large faults in the northeastern margin of the Qinghai-Tibetan plateau are presented; k The general features of the Moho are obtained mainly based on artificial seismic sounding data; l There exists well corresponding relation between surface faults and some features of the Moho, which suggests that such complex crustal structure might be the preparation environment of strong earthquakes.

  18. Dynamic contact mechanics on the tibial plateau of the human knee during activities of daily living.

    Science.gov (United States)

    Gilbert, Susannah; Chen, Tony; Hutchinson, Ian D; Choi, Dan; Voigt, Clifford; Warren, Russell F; Maher, Suzanne A

    2014-06-27

    Despite significant advances in scaffold design, manufacture, and development, it remains unclear what forces these scaffolds must withstand when implanted into the heavily loaded environment of the knee joint. The objective of this study was to fully quantify the dynamic contact mechanics across the tibial plateau of the human knee joint during gait and stair climbing. Our model consisted of a modified Stanmore knee simulator (to apply multi-directional dynamic forces), a two-camera motion capture system (to record joint kinematics), an electronic sensor (to record contact stresses on the tibial plateau), and a suite of post-processing algorithms. During gait, peak contact stresses on the medial plateau occurred in areas of cartilage-cartilage contact; while during stair climb, peak contact stresses were located in the posterior aspect of the plateau, under the meniscus. On the lateral plateau, during gait and in early stair-climb, peak contact stresses occurred under the meniscus, while in late stair-climb, peak contact stresses were experienced in the zone of cartilage-cartilage contact. At 45% of the gait cycle, and 20% and 48% of the stair-climb cycle, peak stresses were simultaneously experienced on both the medial and lateral compartment, suggesting that these phases of loading warrant particular consideration in any simulation intended to evaluate scaffold performance. Our study suggests that in order to design a scaffold capable of restoring 'normal' contact mechanics to the injured knees, the mechanics of the intended site of implantation should be taken into account in any pre-clinical testing regime.

  19. Simulation of Effects of Grassland Degradation on Regional Climate over Sanjiangyuan Region in Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    LIAN Lishu; SHU Jiong

    2009-01-01

    Regional climate model (RegCM3) was applied to explore the possible effects of land use changes (e.g., grassland degradation in this study) on local and regional climate over the Sanjiangyuan region in the Qinghai-Tibet Plateau. Two multiyear (1991-1999) numerical simulation experiments were conducted: one was a control experiment with current land use and the other was a desertification experiment with potential grassland degradation. Preliminary analysis indicated that RegCM3 is appropriate for simulating land-climate interactions, as the patterns of the simulated surface air temperature, the summer precipitation, and the geopotential height fields are consistent with the observed values. The desertification over the Sanjiangyuan region will cause different climate effects in different regions depending on the surrounding environment and climate characteristics. The area with obvious change in surface air temperature inducing by grassland degradation over the Sanjiangyuan region is located in the Qinghai-Tibet Plateau. A winter surface air temperature drop and the other seasons' surface air temperature increase will be observed over the Qinghai-Tibet Plateau based on two numerical simulation experiments. Surface air temperature changes in spring are the largest (0.46℃), and in winter are the smallest (smaller than 0.03℃), indicating an increasing mean annual surface air temperature over the Qinghai-Tibet Plateau. Surface air temperature changes will be smaller and more complex over the surrounding region, with minor winter changes for the regions just outside the plateau and notable summer changes over the north of the Yangtze River. The reinforced summer heat source in the plateau will lead to an intensification of heat low, causing the West Pacific subtropical high to retreat eastward. This will be followed by a decrease of precipitation in summer. The plateau's climate tends to become warm and dry due to the grassland degradation over the Sanjiangyuan

  20. Perfluorinated carboxylic and sulphonic acids in surface water media from the regions of Tibetan Plateau: Indirect evidence on photochemical degradation?

    Science.gov (United States)

    Yamazaki, Eriko; Falandysz, Jerzy; Taniyasu, Sachi; Hui, Ge; Jurkiewicz, Gabriela; Yamashita, Nobuyoshi; Yang, Yong-Liang; Lam, Paul K S

    2016-01-01

    Perfluorinated surfactants and repellents are synthetic substances that have found numerous industrial and customer applications. Due to their persistence, at least two groups of these substances-perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs)-are diffused widely in the environment. It is hypothesized that the Tibetan Plateau, is one of few unique places on the Earth, due to its topography, specifically the vast space and high elevation above sea level, geographic location, climate, high solar radiation, lack of industry, little urbanization and general lack of significant direct sources of pollution. There it is believed possible to gain an insight into atmospheric fate (possible photochemical degradation of higher molecular mass and formation of lower molecular mass PFCAs and PFSAs) of PFASs under un-disturbed environmental conditions. Ultratrace analytical method for PFCAs and PFSAs and use of transportation and field blanks, laboratory blanks and isotopically labelled surrogates for recovery control has allowed the determination of nine perfluorinated carboxylic acids and six perfluorinated sulfonic acids at ultra-trace levels in water based samples from the alpine dimension regions of the Tibetan Plateau, the eastern slope of Minya Konka peak at the eastern edge of the Tibetan Plateau, and also from the city of Chengdu from the lowland of the Sichuan Province in China. The specific compositional pattern of PFCAs and PFSAs and low levels of pollution with those compounds were observed in the central region of the Tibetan Plateau and in the region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau. The fingerprint of the compositional pattern of PFCAs and PFSAs in water samples in the central region of the Tibetan Plateau and in the alpine region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau may be explained by the result of photochemical degradation with dealkylation of longer chain

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

    Science.gov (United States)

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

    2009-06-18

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

  2. Systematical Search for remotely triggered earthquakes in Tibet Plateau following the 2004 M9.2 Sumatra and the 2005 M8.6 Nias earthquake

    Science.gov (United States)

    Yao, D.; Peng, Z.; Meng, X.

    2013-12-01

    The continuous collision between the Indian Plate and Eurasian Plate gives rise to the formation of Tibet Plateau, one of the most complex tectonic environments in the world. In this study, we search for remotely triggered earthquakes in Tibet Plateau following the 2004 M9.2 Sumatra and the 2005 M8.6 Nias Earthquakes. During 2002 to 2005, the Hi-CLIMB (Himalayan-Tibetan Continental Lithosphere during Mountain Building) experiment (IRIS network code XF) was operated in South-Central Tibet, extending from the Ganges lowland, across the Himalayas and into the central Tibetan plateau. Over 200 sites were occupied over this experiment, providing unprecedented continuous recordings around the 2004 Sumatra and the 2005 Nias Earthquakes. On April 7th 2005, nearly 10 days after the 2005 Nias Earthquake, Zhongba was shaken by an Mw 6.3 Earthquake, raising the question on whether this event was delay-triggered by the Nias Earthquake. The Zhongba region is characterized by many NS-trending rift systems that accommodate EW extension, and several moderate-size earthquakes since 2004 suggest that this region is seismically active. Here we use a recently developed matched filter technique to examine seismicity rate changes associated with the 2004 Sumatra and 2005 Nias earthquakes. Specifically, we use 32 relocated earthquakes in Zhongba as templates to detect additional local events between 12/2004 and 05/2005. Although we have detected more than 45 times more events during this time period, we find no statistically significant change in the seismicity rate following the Nias earthquake and before the 2005 Zhongba mainshock. Hence, it is difficult to establish a triggering relationship between these two events. However, after manual inspection of the continuous data during the surface wave trains of the 2004 Sumatra and the 2005 Nias earthquakes, we identify many triggered microearthquakes 350 km north of Zhongba. These dynamically triggered events were located in southern part

  3. Response of grain size of Quaternary gravels to climate and tectonics in the northern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The widely distributed thick gravel deposits along the rim of the Tibetan Plateau have been long thought to be the product of rapid tectonic uplift of the plateau. However, this has been challenged by recent works that suggest these thick gravels may be the result of climate change. In this paper we carried out a detailed field measurement of gravel grain sizes from the Jiuquan and Gobi Gravel Beds in the top of the Laojunmiao section in the Jiuxi Basin in the northern margin of Qilian Mts. (northern Tibetan Plateau). The results suggest that the grain sizes of the Jiuquan and Gobi Gravel Beds over the last 0.8 Ma are characterized by nine coarse-fine cycles having strong 100-ka and 41-ka periodicities that correlate well with the loess-paleosol monsoon record and isotopic global climatic record from deep sea sediments as well as by a long trend of coarsening in gravel grain size. The coarse gravel layers were formed during the warm-humid interglaciations while the fine layers correspond to the cold-dry glaciations. Because the paleoclimate in NW China began to get dramatically drier after the mid-Pleistocene, we think the persistent coarsening of gravel grain size was most probably caused by the rapid uplift of the northern Tibetan Plateau, and that the orbital scale cyclic variations in gravel grain size were driven by orbital forcing factors that were superimposed on the tectonically-forced long-term coarsening trend in gravel size. These findings also shed new light on the interaction results of climate and tectonics in relation to the uplift of the Tibetan Plateau.

  4. Mid-Pliocene onset of eccentricity cycles in the Zhada Basin, southwestern Tibetan Plateau.

    Science.gov (United States)

    Saadeh, C. M.; Saylor, J. E.; Shanahan, T. M.; Nie, J.

    2015-12-01

    Changes in the Asian Monsoon driven by Tibetan Plateau uplift have been invoked to explain late Miocene-Pliocene biological turnover and increases in erosion and sediment accumulation. However, documentation of pre-Miocene uplift of the plateau and evidence for early appearance of the Asian Monsoon system has called these conclusions into question. We present a high-resolution, long-term record of environmental change at 3.5-4.5 km essential to understanding the impact and causes of monsoon variation. The O and C isotopic record of authigenic carbonate in 566 samples from the Zhada Basin extends from 8.99 to 1.75 Ma. Both the δ18O and stratigraphic record indicate long-term changes in basin hydrology which may reflect the impact of regional tectonics on drainage reorganization. These long-term changes are characterized by an onset of lacustrine deposition coupled with an increase in mean δ18O values at 6.11 Ma followed by a return to palustrine/fluvial deposition and a decrease in mean δ18O values at 3.24 Ma. These Miocene-early Pleistocene Zhada Basin results mimic late Pleistocene-Holocene paleoclimatic records across the Tibetan Plateau suggesting similar driving mechanisms. Frequency analysis of the δ18O record reveals that Milankovitch cycles are recorded in the Zhada Basin; suggesting that insolation-driven climate change drove high-frequency environmental changes in the southern Tibetan Plateau. Counterintuitively, non-stationary frequency analysis of the δ18O record indicates strengthening in the 100 kyr (eccentricity) band: coincident with initial onset of Northern Hemisphere Glaciation, but ~2.4 Myr prior to strengthening in the marine record. The discrepancy between marine and high-elevation records suggests that changes in the character of the ISM may be responding to cooling in the Pacific Ocean, and may be responsible for widespread mid-Pliocene changes observed on the peripheries of the Tibetan Plateau.

  5. Observational Facts of Sustained Departure Plateau Vortexes

    Institute of Scientific and Technical Information of China (English)

    YU Shuhua; GAO Wenliang; PENG Jun; XIAO Yuhua

    2014-01-01

    By using the twice-daily atmospheric observation data from 1998 to 2012, station rainfall data, Tropical Rainfall Measure Mission (TRMM) data, as well as the plateau vortex and shear line year book, charac-teristics of the sustained departure plateau vortexes (SDPVs) are analyzed. Some new useful observational facts and understanding are obtained about the SDPV activities. The following results are obtained. (1) The active period of SDPVs is from June to August, most in July, unlike that of the unsustained depar-ture plateau vortexes (UDPVs), which have same occurrence frequencies in the three summer months. (2) The SDPVs, generated mainly in the Qumalai neighborhood and situated in a sheared surrounding, move eastward or northeastward, while the UDPVs are mainly led by the upper-level trough, and move eastward or southeastward. (3) The SDPVs influence wide areas of China, even far to the Korean Peninsula, Japan, and Vietnam. (4) The SDPVs change their intensities and properties on the way to the east. Most of them become stronger and produce downpour or sustained regional rainstorms to the south of Yellow River. (5) The longer the SDPV sustains, the more baroclinity it has. (6) When an SDPV moves into the sea, its central pressure descends and rainfall increases in all probability. (7) An SDPV might spin over the bend of the Yellow River when there exists a tropical cyclone in the East China Sea. It could also move oppositely to a landed tropical low pressure originated from the sea to the east of Taiwan or from the South China Sea.

  6. Rapid regional surface uplift of the northern Altiplano plateau revealed by multiproxy paleoclimate reconstruction

    Science.gov (United States)

    Kar, Nandini; Garzione, Carmala N.; Jaramillo, Carlos; Shanahan, Timothy; Carlotto, Victor; Pullen, Alex; Moreno, Federico; Anderson, Veronica; Moreno, Enrique; Eiler, John

    2016-08-01

    The central Altiplano is inferred to have experienced ∼ 2.5 ± 1km surface uplift between ∼10 and 6 Ma, while the southern Altiplano experienced a similar magnitude of surface uplift that began earlier, between ∼16 and 9 Ma. To properly constrain the along strike timing of the Altiplano plateau surface uplift, it is necessary to know how and when the northernmost part of the Altiplano plateau evolved. We reconstruct the paleoclimate and infer the corresponding paleoelevation from the Miocene-Pliocene deposits of the Descanso-Yauri basin (14-15°S) in the northernmost part of the Altiplano plateau using 4 different proxies, including carbonate clumped isotope composition (i.e., Δ47 values), carbonate δ18Oc, leaf wax δDwax and pollen assemblages from paleosol, lacustrine and palustrine carbonates and organic-rich sediments. The isotopic signatures reflect past climate conditions of mean annual air temperature (Δ47) and meteoric water isotope values (δ18Oc, δDwax). Our results show that the northernmost plateau remained at low elevation (0.9 ± 0.8 to 2.1 ± 0.9km) until late Miocene time (∼9 Ma) characterized by ∼15 °C warmer than modern temperature (mean annual air temperature of 23 ± 4 °C, 2σ), low elevation vegetation and precipitation signature with reconstructed □ δ18Omw (VSMOW) of - 8.3 ± 2.0 ‰ (2 σ) from carbonate (δ18Oc) and - 8.6 ± 1.8 ‰ (2 σ) from leaf wax (δDwax). Modern elevations of 4 km were not reached until 5.4 ± 1.0Ma, as indicated by a negative shift in δDwax (VSMOW) from - 143.4 ± 12.8 ‰ (2 σ) to - 209.2 ± 21.1 ‰ (2 σ) between 9.1 ± 0.7 and 5.4 ± 1.0Ma. The timing of surface uplift of the northernmost Altiplano is consistent with the evidence for late Miocene surface uplift of the central Altiplano (16-19°S) between 10 and 6 Ma, and indicates that regional scale uplift in the northern-central plateau significantly postdates the onset of surface uplift in the southern Altiplano (19-22°S) between ∼16

  7. Characteristics of land-atmosphere energy and turbulent fluxes over the plateau steppe in central Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    MaoShan Li; ZhongBo Su; YaoMing Ma; XueLong Chen; Lang Zhang; ZeYong Hu

    2016-01-01

    The land-atmosphere energy and turbulence exchange is key to understanding land surface processes on the Tibetan Plateau (TP). Using observed data for Aug. 4 to Dec. 3, 2012 from the Bujiao observation point (BJ) of the Nagqu Plateau Climate and Environment Station (NPCE-BJ), different characteristics of the energy flux during the Asian summer monsoon (ASM) season and post-monsoon period were analyzed. This study outlines the impact of the ASM on energy fluxes in the central TP. It also demonstrates that the surface energy closure rate during the ASM season is higher than that of the post-monsoon period. Footprint modeling shows the distribution of data quality assessments (QA) and quality controls (QC) surrounding the observation point. The measured turbulent flux data at the NPCE-BJ site were highly rep-resentative of the target land-use type. The target surface contributed more to the fluxes under unstable conditions than under stable conditions. The main wind directions (180° and 210°) with the highest data density showed flux contributions reaching 100%, even under stable conditions. The lowest flux contributions were found in sectors with low data density, e.g., 90.4% in the 360° sector under stable conditions during the ASM season. Lastly, a surface energy water balance (SEWAB) model was used to gap-fill any absent or corrected turbulence data. The potential simulation error was also explored in this study. The Nash-Sutcliffe model efficiency coefficients (NSEs) of the observed fluxes with the SEWAB model runs were 0.78 for sensible heat flux and 0.63 for latent heat flux during the ASM season, but unrealistic values of−0.9 for latent heat flux during the post-monsoon period.

  8. Geochemical Characteristics of the Cenozoic Volcanic Rocks in Central Qiangtang, Tibet: Relation with the Uplift of the Qinghai Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    TAN Fuwen; PAN Guitang; XU Qiang

    2001-01-01

    The Cenozoic volcanic rocks in central Qiangtang are tectonically outcropped in the transitional area where crust of the Qinghai-Tibet Plateau thins northwards and the Passion's ratios of the crust increases abnormally northwards. Of all Cenozoic volcanic rocks of northern Tibet, the volcanic rocks in Qiangtang area is the oldest one with ages from 44.1±1.0 Ma to 32.6±0.8 Ma. Petrological and geochemical studies of the volcanic rocks in central Qiangtang suggest they formed in the extension environment of post collision-orogeny and were the product of mixture of magmas from crust and mantle. The uplift of the northern plateau is closely related to decoupling of mantle lithosphere,crustal extension and thinning as well as volcanism. Therefore, it is inferred that the main uplift of the northern plateau began from about 40 Ma ago.

  9. Quaternary geomorphological evolution of the Kunlun Pass area and uplift of the Qinghai-Xizang (Tibet) Plateau

    Science.gov (United States)

    Wu, Yongqiu; Cui, Zhijiu; Liu, Gengnian; Ge, Daokai; Yin, Jiarun; Xu, Qinghai; Pang, Qiqing

    2001-02-01

    There is a set of Late Cenozoic sediments in the Kunlun Pass area, Tibetan Plateau, China. Paleomagnetic, ESR and TL dating suggest that they date from the Late Pliocene to the Early Pleistocene. Analyses of stratigraphy, sedimentary characteristic, and evolution of the fauna and flora indicate that, from the Pliocene to the early Quaternary (about 5-1.1 Ma BP), there was a relatively warm and humid environment, and a paleolake occurred around the Kunlun Pass. The elevation of the Kunlun Pass area was no more than 1500 m, and only one low topographic divide existed between the Qaidam Basin and the Kunlun Pass Basin. The geomorphic pattern in the Kunlun Pass area was influenced by the Kunlun-Yellow River Tectonic Movement 1.1-0.6 Ma BP. The Wangkun Glaciation (0.7-0.5 Ma) is the maximum Quaternary glaciation in the Pass and in other areas of the Plateau. During the glaciation, the area of the glaciers was 3-5 times larger than that of the present glacier in the Pass area. There was no Xidatan Valley that time. The extreme geomorphic changes in the Kunlun Pass area reflect an abrupt uplift of the Tibet Plateau during the Early and Middle Pleistocene. This uplift of the Plateau has significance on both the Plateau itself and the surrounding area.

  10. Butterflies of the Bodoquena Plateau in Brazil (Lepidoptera, Papilionoidea)

    Science.gov (United States)

    de Souza, Paulo Ricardo Barbosa; Guillermo-Ferreira, Rhainer

    2015-01-01

    Abstract Butterflies and moths are found in all terrestrial environments and require efforts for a better understanding of its mega-diversity. These taxa have been the subject of several studies involving phylogeny, ecology and environmental impacts. Nevertheless, several areas in the tropics remain unexplored, resulting in gaps in the taxonomic composition and distribution of butterflies in endemic environments. Therefore, a survey of the butterfly fauna of the Bodoquena Plateau in Brazil was conducted. This area consists of tropical Atlantic Forests, with marginal influences of Savannah, Chaco and Pantanal. Sampling was carried out in 20 locations using Van Someren Rydon traps and insect nets between November 2009 and April 2015. Active collection of individuals was conducted from 9:00 to 17:00h, totaling 240 hours of sampling effort. In total, we registered 768 individuals belonging to 146 species of 98 genera, six families and 18 subfamilies. Nymphalidae was the richest family (84 species), followed by Hesperiidae (22 species), Riodinidae (14 species), Pieridae (12) Papilionidae (11 species) and Lycaenidae (five species). We sampled 239 nymphalids in traps, with 48 species, 30 genera, 15 tribes and five subfamilies. The most common species were Eunica macris (Godart, 1824), Dynamine artemisia (Fabricius, 1793) and Memphis moruus (Fabricius, 1775). Therefore, this study contributes to the knowledge of the Neotropical butterfly diversity and distribution, providing 37 new records and supporting the use of wildlife inventories as important tools for the knowledge of tropical forests biodiversity and conservation. PMID:26798308

  11. Butterflies of the Bodoquena Plateau in Brazil (Lepidoptera, Papilionoidea).

    Science.gov (United States)

    de Souza, Paulo Ricardo Barbosa; Guillermo-Ferreira, Rhainer

    2015-01-01

    Butterflies and moths are found in all terrestrial environments and require efforts for a better understanding of its mega-diversity. These taxa have been the subject of several studies involving phylogeny, ecology and environmental impacts. Nevertheless, several areas in the tropics remain unexplored, resulting in gaps in the taxonomic composition and distribution of butterflies in endemic environments. Therefore, a survey of the butterfly fauna of the Bodoquena Plateau in Brazil was conducted. This area consists of tropical Atlantic Forests, with marginal influences of Savannah, Chaco and Pantanal. Sampling was carried out in 20 locations using Van Someren Rydon traps and insect nets between November 2009 and April 2015. Active collection of individuals was conducted from 9:00 to 17:00h, totaling 240 hours of sampling effort. In total, we registered 768 individuals belonging to 146 species of 98 genera, six families and 18 subfamilies. Nymphalidae was the richest family (84 species), followed by Hesperiidae (22 species), Riodinidae (14 species), Pieridae (12) Papilionidae (11 species) and Lycaenidae (five species). We sampled 239 nymphalids in traps, with 48 species, 30 genera, 15 tribes and five subfamilies. The most common species were Eunica macris (Godart, 1824), Dynamine artemisia (Fabricius, 1793) and Memphis moruus (Fabricius, 1775). Therefore, this study contributes to the knowledge of the Neotropical butterfly diversity and distribution, providing 37 new records and supporting the use of wildlife inventories as important tools for the knowledge of tropical forests biodiversity and conservation.

  12. Characterizing the Severe Turbulence Environments Associated With Commercial Aviation Accidents: A Real-Time Turbulence Model (RTTM) Designed for the Operational Prediction of Hazardous Aviation Turbulence Environments

    Science.gov (United States)

    Kaplan, Michael L.; Lux, Kevin M.; Cetola, Jeffrey D.; Huffman, Allan W.; Riordan, Allen J.; Slusser, Sarah W.; Lin, Yuh-Lang; Charney, Joseph J.; Waight, Kenneth T.

    2004-01-01

    Real-time prediction of environments predisposed to producing moderate-severe aviation turbulence is studied. We describe the numerical model and its postprocessing system designed for said prediction of environments predisposed to severe aviation turbulence as well as presenting numerous examples of its utility. The numerical model is MASS version 5.13, which is integrated over three different grid matrices in real time on a university work station in support of NASA Langley Research Center s B-757 turbulence research flight missions. The postprocessing system includes several turbulence-related products, including four turbulence forecasting indices, winds, streamlines, turbulence kinetic energy, and Richardson numbers. Additionally, there are convective products including precipitation, cloud height, cloud mass fluxes, lifted index, and K-index. Furthermore, soundings, sounding parameters, and Froude number plots are also provided. The horizontal cross-section plot products are provided from 16 000 to 46 000 ft in 2000-ft intervals. Products are available every 3 hours at the 60- and 30-km grid interval and every 1.5 hours at the 15-km grid interval. The model is initialized from the NWS ETA analyses and integrated two times a day.

  13. Bed-material entrainment and associated transportation infrastructure problems in streams of the Edwards Plateau, central Texas

    Science.gov (United States)

    Heitmuller, Franklin T.; Asquith, William H.

    2008-01-01

    The Texas Department of Transportation commonly builds and maintains low-water crossings (LWCs) over streams in the Edwards Plateau in Central Texas. LWCs are low-height structures, typically constructed of concrete and asphalt, that provide acceptable passage over seasonal rivers or streams with relatively low normal-depth flow. They are designed to accommodate flow by roadway overtopping during high-flow events. The streams of the Edwards Plateau are characterized by cobble- and gravel-sized bed material and highly variable flow regimes. Low base flows that occur most of the time occasionally are interrupted by severe floods. The floods entrain and transport substantial loads of bed material in the stream channels. As a result, LWCs over streams in the Edwards Plateau are bombarded and abraded by bed material during floods and periodically must be maintained or even replaced.

  14. Evolution of Chinese mammalian faunal regions and elevation of the Qinghai-Xizang (Tibet) Plateau

    Institute of Scientific and Technical Information of China (English)

    QIU Zhuding; LI Chuankui

    2005-01-01

    On the basis of mammal's high evolutionary rates and sensitivity to environment, this paper deals with the evolutionary history of the Chinese Cenozoic mammals and environmental changes, and explores the relationship between the uplift of the Qinghai-Xizang Plateau and the evolution of zoogeographic provinces of China, through studying fossil mammal and the lithological characters of fossil-bearing beds. Evolutionary tendency and distribution of the mammals demonstrate that the uplift of the Qinghai-Xizang region, onset of the Asian monsoon and differentiation of the mammalian distribution probably initiated in Oligocene. The elevation of the Plateau seems to be a gradual and relatively stable process, and the uplift not only has resulted in significant environmental changes in Asia, but also caused distinct regional differentiation of mammals in China since the middle Miocene, and as a consequence the modern zoogeographic provinces gradually took shape.

  15. Volcanic succession of the Borovnik Member (Mohorje Formation, Bloke Plateau area, Central Slovenia

    Directory of Open Access Journals (Sweden)

    Stevo Dozet

    2009-06-01

    Full Text Available A 75 m thick volcanic succession of the Borovnik Member, Mohorje Formation in the Bloke Plateau area consistsof dacitic and rhyolitic rocks deposited in a shallow-marine environment. Volcanic activity begun with lavaflows that underwent extensive disintegration, autobrecciation and mixing with the underlying unconsolidated fine-grained clastic sediments producing dacite/rhyolite-siltstone peperites. Peperites are very rich in fractured plagioclase phenocrysts, and owing to the incorporation of clastic material, they are commonly depleted in silica.The overlying fining-upward pyroclastic sequence is monotonous. Basal parts mainly consist of coarse-grained vitric tuffs that may contain some smaller pumice lapilli. The overlying volcaniclastics are fine-grained vitric tuffs,and in the uppermost parts of the sequence, they are interbedded with cherts.The study confirms the existence of primary volcaniclastic succession in the Bloke Plateau area and excludes its epiclastic or reworked origin.

  16. Miocene to present-day shortening and intermontane basin formation in the Andean Puna Plateau, NW Argentina (24°30'S)

    Science.gov (United States)

    Strecker, M. R.; Bookhagen, B.; Alonso, R. N.; Pingel, H.; Freymark, J.

    2015-12-01

    With average elevations of about 3.7 km the Altiplano-Puna Plateau of the southern central Andes constitutes the world's second largest orogenic plateau. The plateau generally consists of internally drained, partly coalesced sedimentary basins bordered by reverse-fault bounded ranges, >5 km high. In the Puna, the Argentine sector of the plateau, active tectonism has been interpreted to be characterized by a low level of strike-slip and normal faulting associated with mafic volcanism. In contrast, the eastern plateau margins and the adjacent foreland record a higher level of seismicity and ongoing contraction. Despite ubiquitous Plio-Pleistocene normal faulting along the eastern plateau margins, our new observations record contraction in the plateau interior. Fanning of E-dipping Miocene sedimentary strata involved in the formation of an anticline in the Pocitos Basin of the central Puna interior indicates growth, which must have begun after 7 Ma; 1.5-m.y.-old lacustrine strata as well as tilted Pleistocene lacustrine shorelines associated with this structure indicate sustained uplift into the Quaternary. Corresponding observations along the eastern border of the Pocitos Basin show that <3.5-m.y.-old strata are involved in contractile deformation and basin compartmentalization. Shortening in the central Puna is compatible with Plio-Pleistocene shortening in the low-elevation Salar de Atacama farther west, and may indicate that low-elevation sectors of the plateau have not yet reached a critical elevation that is conducive to normal faulting as observed elsewhere. The onset of extensional deformation in the Puna is thus highly disparate in space and time. Coeval regional thrusting, strike-slip, and normal faulting do not support a structural and topographic setting that promotes wholesale extension and orogenic collapse of the plateau realm.

  17. Sedimentary record of regional deformation and dynamics of the thick-skinned southern Puna Plateau, central Andes (26-27°S)

    Science.gov (United States)

    Zhou, Renjie; Schoenbohm, Lindsay M.; Sobel, Edward R.; Carrapa, Barbara; Davis, Donald W.

    2016-01-01

    The Puna Plateau, adjacent Eastern Cordillera and the Sierras Pampeanas of the central Andes are largely characterized by thick-skinned, basement-involved deformation. The Puna Plateau hosts ∼N-S trending bedrock ranges bounded by deep-seated reverse faults and sedimentary basins. We contribute to the understanding of thick-skinned dynamics in the Puna Plateau by constraining regional kinematics of the poorly understood southern Puna Plateau through a multidisciplinary approach. On the southeastern plateau, sandstone modal composition and detrital zircon U-Pb and apatite fission-track data from Cenozoic strata indicate basin accumulation during the late Eocene to early Oligocene (∼38-28 Ma). Provenance analysis reveals the existence of a regional-scale basin covering the southern Puna Plateau during late Eocene to early Oligocene time (∼38-28 Ma) that was sourced from both the western plateau and the eastern plateau margin and had a depocenter located to the west. Petrographic and detrital zircon U-Pb data reveal erosion of proximal western and eastern sources after ∼12 Ma, in mid-late Miocene time. This indicates that the regional basin was compartmentalized into small-scale depocenters by the growth of basement-cored ranges continuing into the late Miocene (∼12-8 Ma). We suggest that the Cenozoic history of the southern Puna Plateau records the formation of a regional basin that was possibly driven by lithospheric flexure during the late Eocene to early Oligocene, before the growth of distributed basement-cored ranges starting as early as the late Oligocene.

  18. 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.

  19. Microplastic pollution of lakeshore sediments from remote lakes in Tibet plateau, China.

    Science.gov (United States)

    Zhang, Kai; Su, Jing; Xiong, Xiong; Wu, Xiang; Wu, Chenxi; Liu, Jiantong

    2016-12-01

    Tibetan Plateau is known as the world's third pole, which is characterized by a low population density with very limited human activities. Tibetan Plateau possesses the greatest numbers of high-altitude inland lakes in the world. However, no information is currently available on the characteristic of microplastic pollution in those lakes within this remote area. In this work, lakeshore sediments from four lakes within the Siling Co basin in northern Tibet were sampled and examined for microplastics (plastic products. Polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinyl chloride were identified from the microplastic samples using laser Raman spectroscopy, and oxidative and mechanical weathering textures were observed on the surface of microplastics using scanning electron microscope. These results demonstrate the presence of microplastics even for inland lakes in remote areas under very low human impact, and microplastic pollution can be a global issue.

  20. Ground motion parameters of Shillong plateau: One of the most seismically active zones of northeastern India

    Institute of Scientific and Technical Information of China (English)

    Saurabh Baruah; Santanu Baruah; Naba Kumar Gogoi; Olga Erteleva; Felix Aptikaev; J.R.Kayal

    2009-01-01

    Strong ground motion parameters for Shillong plateau of northeastern India are examined. Empirical relations are obtained for main parameters of ground motions as a function of earthquake magnitude, fault type, source depth, velocity characterization of medium and distance. Correlation between ground motion parameters and characteristics of seismogenic zones are established. A new attenuation relation for peak ground acceleration is developed, which predicts higher expected PGA in the region. Parameters of strong motions, particularly the predominant periods and duration of vibrations, depend on the morphology of the studied area. The study measures low estimates of logarithmic width in Shillong plateau. The attenuation relation estimated for pulse width critically indicates increased pulse width dependence on the logarithmic distance which accounts for geometrical spreading and anelastic attenuation.

  1. The Manihiki Plateau, Hikurangi Plateau, Wishbone Scarp, and Osbourn Trough: A Review and Analysis

    Science.gov (United States)

    Henig, A.; Luyendyk, B. P.

    2007-12-01

    The extinct Osbourn Trough spreading system in the southwestern Pacific played a key role in separating the once joined Hikurangi and Manihiki Plateaus in Cretaceous time. Recent studies by Downey et al. [2007] and Taylor [20006] have provided new data and concepts on that history. Studies by Larson et al. [2002] describe Cretaceous histories adjacent and east of the Osbourn system and Eagles et al. [2004] describe a history for the southwest Pacific just after the Osbourn system became extinct. The lack of identifiable magnetic anomalies allows tectonic events during separation of the plateaus and spreading on the Osbourn Trough to occur between about 124.6 and 84 Ma (Chron 34). Satellite gravity maps of the region identify what are interpreted as Cretaceous fracture zone trends. Swath bathymetry data reveal at least four provinces of abyssal hill trends. What is known are the following: Minimum age of the Manihiki High Plateau at 123.4 Ma from DSDP Site 317, the age of seafloor, 115 Ma, from a dredge sample from the southern segment of the West Wishbone Scarp 300 km northeast of the Hikurangi Plateau, the east-west trend and extent of the extinct Osbourn spreading center at latitude 26° S, the trends (NNE-SSW to NE-SW) and extent of portions of the West Wishbone Scarp east of the Hikurangi Plateau, the N-S trend of the East Wishbone Scarp that appears to truncate the West Wishbone Scarp, the NNE- SSW trend and extent of the prominent Manihiki (Eastern) Scarp at the eastern boundary of the Manihiki High Plateau, the NW-SE trend and extent of the Rapuhia Scarp on the northwestern Hikurangi Plateau, and trends in abyssal hills; E-W near the Osbourn Trough and WNW-ESE closer to the plateaus. Differences in abyssal hill morphology suggest one or more changes in spreading rates. The Osbourn Trough began rifting apart a Large Igneous Province formed at 123.5 +/- 1.5 Ma, into the separate Ontong-Java, Manihiki, and Hikurangi Plateaus by 121 Ma. After an initial 6 Myr

  2. Interpretation of Plateau in High-Harmonic Generation

    Institute of Scientific and Technical Information of China (English)

    程太旺; 李晓峰; 敖淑艳; 傅盘铭

    2003-01-01

    The plateau in high-harmonic generation is investigated in the frequency domain. Probability density of an electron in an electromagnetic field is obtained through analysing the quantized-field Volkov state. The plateau of high-harmonic generation reflects the spectral density of the electron at the location of nucleus after abovethreshold ionization.

  3. A Moessbauer and Electrochemical Characterization of the Corrosion Products Formed from Marine and Marine-Antartic Environments

    Energy Technology Data Exchange (ETDEWEB)

    Ohanian, M.; Caraballo, R.; Dalchiele, E. A.; Quagliata, E. [Instituto de Ingenieria Quimica, Facultad de Ingenieria (Uruguay)

    2003-06-15

    Corrosion products formed on low alloy steel under two marine environments are characterised. Both environments are classified as C4 according to the ISO 9223 Standard. The corrosion products are identified and their relative proportion is determined by Moessbauer spectroscopy (transmission geometry). Free potentials of corrosion are measured to evaluate the activity of their surfaces. Structural characterisation by XRD were performed on selected samples. It is concluded that the principal phases are goethite, lepidocrocite, ferrihidrite and maghemite. The relative amount of each of them changes with time and with the atmospheric dynamics of each environment.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-06

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

  5. Characterization of System Level Single Event Upset (SEU) Responses using SEU Data, Classical Reliability Models, and Space Environment Data

    Science.gov (United States)

    Berg, Melanie; Label, Kenneth; Campola, Michael; Xapsos, Michael

    2017-01-01

    We propose a method for the application of single event upset (SEU) data towards the analysis of complex systems using transformed reliability models (from the time domain to the particle fluence domain) and space environment data.

  6. Modeling and preliminary characterization of passive, wireless temperature sensors for harsh environment applications based on periodic structures

    Science.gov (United States)

    Delfin Manriquez, Diego I.

    Wireless temperature sensing has attained significant attention in recent years due to the increasing need to develop reliable and affordable sensing solutions for energy conversion systems and other harsh environment applications. The development of next generation sensors for energy production processing parameters, such as temperature and pressure, can result in better performance of the system. Particularly, continuous temperature monitoring in energy conversion systems can result in enhancements such as better system integrity, less pollution and higher thermal efficiencies. However, the conditions experienced in these system components hinder the performance of current solutions due to the presence of semi-conductor materials and welded joints. Additionally, the use of wired systems can result in complex wiring networks, increasing the cost of installation, maintenance and sensor replacement. Therefore, next generation sensing solutions must be developed to overcome current challenges in systems where adverse conditions are present. This research project proposes two novel passive, wireless temperature sensor designs based on concepts of guided mode resonance filters (GMRF) and metamaterials. For the GMRF, a tri-layer structure using a metallic encasing and a circular aperture grating layer was developed to have a resonance frequency of 10 GHz. While for the metamaterial-based sensor a continuation of previous work was presented by utilizing a dielectric substrate and an array of commercially available metallic washers divided in two layers. For both designs, High Frequency Structure Simulator (HFSS) from ANSYSRTM was employed to assess the feasibility of the sensor as well as to optimize the geometry and guide the fabrication process. A systematic approach consisting of evaluating the unit cell, then assessing the number of periods needed, and finally characterizing the response of the final sensor was followed for each case. After the modeling process was

  7. 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.

  8. Extension of the Yellowstone plateau, eastern Snake River Plain, and Owyhee plateau

    Science.gov (United States)

    Rodgers, David W.; Hackett, William R.; Ore, H. Thomas

    1990-11-01

    Formation of the late Cenozoic volcanic province comprising the Owyhee plateau, eastern Snake River Plain, and Yellowstone plateau has been accompanied by east-northeast-directed crustal extension. A new vector of 45 mm/yr, N56°E for the migration of silicic volcanism across the volcanic province is calculated. If migration of volcanism reflects west-southwest continental drift over a mantle plume, a zone of crustal extension must separate the volcanic province from the more slowly moving North American craton. Space-time relations of basin fill in the adjacent Basin and Range province provide evidence for a zone of extension, about 125 km wide, coincident with and east of coeval silicic volcanism. Since 16 Ma, the zone of extension has migrated along with silicic volcanism, maintaining its position between the province and the unextended craton.

  9. Deep structure of the Iceland plateau

    Energy Technology Data Exchange (ETDEWEB)

    Evans, J.R.; Sacks, I.S.

    1979-11-10

    The topography of the sea floor between Iceland and Jan Mayen Island is flat and elevated in relation to most ocean basins. Marine geophysical observations in the area have shown that it was formed by sea floor spreading but have not revealed details of structures more than a few hundred meters beneath the sea floor. We have examined the dispersion of seismic surface waves across the Iceland Plateau and have modeled structures to depths of up to 100 km. We find that the thickness of the crustal component of the lithosphere is much greater than that of normal oceanic structures, perhaps exceeding 20 km. We suggest that the elevation of the region is due to isostatic compensation for this excess of low-density crustal material. The total lithospheric thickness is about 50 km throughout the region, indicating that the lithosphere thickens with age at a rate similar to that found in other young oceans.

  10. Plateau inflation in SUGRA-MSSM

    Science.gov (United States)

    Chakravarty, Girish Kumar; Gupta, Gaveshna; Lambiase, Gaetano; Mohanty, Subhendra

    2016-09-01

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

  11. Plateau inflation in SUGRA-MSSM

    Directory of Open Access Journals (Sweden)

    Girish Kumar Chakravarty

    2016-09-01

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

  12. Impact of Cryosphere Hydrological Changes on the River Runoff in the Tibetan Plateau

    Science.gov (United States)

    Wang, Y.; Yang, D.

    2015-12-01

    The Tibetan Plateau is the headwaters of many major rivers in Asia, the change in streamflow is significant for social and economic development and natural ecology in the middle and lower reaches. Located in the alpine region, streamflow in the plateau is mainly affected by the cryosphere hydrological processes. Due to global warming in recent decades, the Tibetan Plateau is experiencing glaciers shrinking and permafrost degradation. Accelerated glacier melt led to the increasing meltwater, thus affecting the streamflow. Permafrost is an important factor in stabilizing the water cycle and streamflow, the ecological degradation and the significant changes of rivers, lakes, swamps, wetlands and other hydrological environment in recent decades in the Tibetan plateau is closely related to permafrost degradation. Therefore, it is important to explore the impact of cryosphere hydrological changes on the streamflow for the future water management. This study uses a method of base flow separation and a stepwise multiple regression model to investigate the reasons for the runoff changes in different regions of the Tibetan Plateau during 1960-2000. The contribution of glacier melt to annual runoff is particularly estimated to explore the possible influences of soil freezing and thawing on annual runoff changes. The results show an increasing trend of the annual runoff in the upstream of Nujiang River, Lancang River and Qilian Mountains, dominated by the increasing of base flow; and a decreasing trend of the runoff in the upper reach of the Yarlung Zangbo River, Yellow River and Yangtze River, dominated by the reduction of quick flow. Change in the amount of runoff was mainly due to change in precipitation. Rising temperature accelerates the melting of glaciers and increases the summer quick flow. In addition, rising temperature may reduce the quick flow and increase the base flow due to change of the active permafrost layers, which leads to the increase of soil water storage

  13. Development of highway constructing technology in the permafrost region on the Qinghai-Tibet plateau

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Qinghai-Tibet Highway passes through the Qinghai-Tibet plateau hinterland from north to south, from Kunlun Mountain to Tanggula Mountain. The average altitude is above 4500 m and permafrost covers more than 700 km length of area with high elevation and high temperature. The climate of the plateau is capricious and the surroundings along the road are bad, where the mean annual atmosphere temperature is -2 to -7℃ and the oxygen content is inadequate, which is less than 50% of the sea level, while the solar radiation is higher than 3600 kJ/m2. The basic characteristics of the plateau surroundings are the permafrost, coldness with litter oxygen, and fragile ecosystem. As the air temperature warms all over the world, the permafrost on the plateau responds quickly. The average temperature of permafrost is up by 0.2―0.3℃ in recent 20 years, and the island-permafrost dwindles with a high rate, and the high temperature permafrost degrades quickly, and the temperature of the low temperature permafrost increases remarkably. These gradually cause the highway engineering diseases in the permafrost region. The Qinghai-Tibet highway has experienced much maintenance and rebuilding for 50 years after it was built, and the continual observation and investigation have been made for more than 30 years. This road is the longest test engineering for permafrost research work in China. It is no doubt that it is also the greatest engineering project in plateau permafrost region. The Ministry of Communication in China initiated the research project "Research on a series of technologies for highway constructing in the permafrost regions" in 2002, which was to meet the challenges from the effect of climatic warming on the permafrost. The project systematically studied the permafrost engineering theories, methods for survey and design, engineering stabilization measures, preventing of the road disasters and maintaining, environment protection and the techniques to prolong the road

  14. Development of highway constructing technology in the permafrost region on the Qinshai-Tibet plateau

    Institute of Scientific and Technical Information of China (English)

    WANG ShuangJie; CHEN JianBing; ZHANG JinZhao; LI ZhuLong

    2009-01-01

    The Qinghai-Tibet Highway passes through the Qinghai-Tibet plateau hinterland from north to south, from Kunlun Mountain to Tanggula Mountain. The average altitude is above 4500 m and permafrost covers more than 700 km length of area with high elevation and high temperature. The climate of the plateau is capricious and the surroundings along the road are bad, where the mean annual atmosphere temperature is -2 to -7℃ and the oxygen content is inadequate, which is less than 50% of the sea level, while the solar radiation is higher than 3600 kJ/m2. The basic characteristics of the plateau surround-ings are the permafrost, coldness with litter oxygen, and fragile ecosystem. As the air temperature warms all over the world, the permafrost on the plateau responds quickly. The average temperature of permafrost is up by 0.2-0.3℃ in recent 20 years, and the island-permafrost dwindles with a high rate,and the high temperature permafrost degrades quickly, and the temperature of the low temperature permafrost increases remarkably. These gradually cause the highway engineering diseases in the permafrost region. The Qinghai-Tibet highway has experienced much maintenance and rebuilding for 50 years after it was built, and the continual observation and investigation have been made for more than 30 years. This road is the longest test engineering for permafrost research work in China. It is no doubt that it is also the greatest engineering project in plateau permafrost region. The Ministry of Communication in China initiated the research project "Research on a series of technologies for highway constructing in the permafrost regions" in 2002, which was to meet the challenges from the effect of climatic warming on the permafrost. The project systematically studied the permafrost engi- neering theories, methods for survey and design, engineering stabilization measures, preventing of the road disasters and maintaining, environment protection and the techniques to prolong the road

  15. Geochemistry and petrogenesis of Neoproterozoic Mylliem granitoids, Meghalaya Plateau, northeastern India

    Indian Academy of Sciences (India)

    Jyotisankar Ray; Abhishek Saha; Sohini Ganguly; V Balaram; A Keshav Krishna; Sampa Hazra

    2011-06-01

    The Mylliem granitoids of the Meghalaya Plateau, northeastern India, represent one of the disharmonic Neoproterozoic igneous plutons, which are intrusive into low-grade Shillong Group of metasediments. Field studies indicate that the Mylliem granitoids cover an area of about 40 km2 and is characterized by development of variable attitude of primary foliations mostly marked along the margin of the pluton. Xenoliths of both Shillong Group of metasediments and mafic rocks have been found to occur within Mylliem granitoids. Structural study of the primary foliation is suggestive of funnel-shaped intrusion of Mylliem granitoids with no appreciable evidence of shearing. Petrographically, Mylliem granitoids are characterized by pink to white phenocrysts of prismatic microcline/perthite and lath-shaped plagioclase (An20–An29). Groundmass material is characterized by quartz, microcline, plagioclase, muscovite and biotite. Sphene and apatite occur as accessory minerals. Petrographically Mylliem granitoids have been discriminated as granite and granodiorite according to IUGS system of classification. Critical evaluation of geochemical data and variation trends of major oxides/trace elements suggests a significant role of fractional crystallization in the evolution of Mylliem pluton. Th/U ratios (3.22–6.77) indicate a relatively higher abundance of Th over U. Chondrite-normalized REE diagram characteristically shows an enriched LREE pattern and prominent negative Eu anomaly (Eu/Eu* = 0.16–0.42) indicating the significant role of plagioclase fractionation from the parent magma. An overall strong REE fractionation pattern has been envisaged for Mylliem granitoids. The strong REE fractionation of the Mylliem granitoids is depicted by (Ce/Yb) values, which show a range of 1.39 to 1.65. The aluminium saturation index (ASI) (ranging from 1.0 to 1.3), A/CNK ratios (ranging from 1.4 to 2.11) and A/NK ratios (ranging from 1.75 to 2.43) provide evidences for the peraluminous, S

  16. Have Periprosthetic Hip Infection Rates Plateaued?

    Science.gov (United States)

    Perfetti, Dean C; Boylan, Matthew R; Naziri, Qais; Paulino, Carl B; Kurtz, Steven M; Mont, Michael A

    2017-07-01

    Periprosthetic joint infection (PJI) is a serious complication of total hip arthroplasty (THA). Although the number of revision cases is increasing, the prevalence of PJI as an indication for revision surgery, and the variability of this indication among surgeons and hospitals, is unclear. The New York Statewide Planning and Research Cooperative System was used to identify 33,582 patients undergoing revision THA between 2000 and 2013. PJI was identified using International Classification of Diseases, Ninth Revision diagnosis codes. Volume was defined using mean number of revision THAs performed annually by each hospital and surgeon. PJI was the indication for 13.0% of all revision THAs. The percentage of revision THAs for PJI increased between years 2000 and 2007 (odds ratio [OR] = 1.05, P < .001), but decreased between years 2008 and 2013 (OR = 0.96, P = .001). Compared to medium-volume hospitals, the PJI burden at high-volume hospitals decreased during years 2000-2007 (OR = 0.58, P < .001) and 2008-2013 (OR = 0.57, P < .001). Compared to medium-volume surgeons, the PJI burden for high-volume surgeons increased during years 2000-2007 (OR = 1.39, P < .001), but did not differ during years 2008-2013 (P = .618). The burden of PJI as an indication for revision THA may be plateauing. High-volume institutions have seen decreases in the percentage of revisions performed for PJI over the complete study duration. Specific surgeon may be associated with the plateauing in PJI rates as high-volume surgeons in 2008-2013 were no longer found to be at increased risk of PJI as an indication for revision THA. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Characterizing the effect of creep on stress corrosion cracking of cold worked Alloy 690 in supercritical water environment

    Science.gov (United States)

    Zhang, Lefu; Chen, Kai; Du, Donghai; Gao, Wenhua; Andresen, Peter L.; Guo, Xianglong

    2017-08-01

    The effect of creep on stress corrosion cracking (SCC) was studied by measuring crack growth rates (CGRs) of 30% cold worked (CW) Alloy 690 in supercritical water (SCW) and inert gas environments at temperatures ranging from 450 °C to 550 °C. The SCC crack growth rate under SCW environments can be regarded as the cracking induced by the combined effect of corrosion and creep, while the CGR in inert gas environment can be taken as the portion of creep induced cracking. Results showed that the CW Alloy 690 sustained high susceptibility to intergranular (IG) cracking, and creep played a dominant role in the SCC crack growth behavior, contributing more than 80% of the total crack growth rate at each testing temperature. The temperature dependence of creep induced CGRs follows an Arrhenius dependency, with an apparent activation energy (QE) of about 225 kJ/mol.

  18. A Possible Impact of Cooling over the Tibetan Plateau on the Mid-Holocene East Asian Monsoon Climate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    By using a 9-level global atmospheric general circulation model developed at the Institute of Atmospheric Physics (IAP9L-AGCM) under the Chinese Academy of Sciences, the authors investigated the response of the East Asian monsoon climate to changes both in orbital forcing and the snow and glaciers over the Tibetan Plateau at the mid-Holocene, about 6000 calendar years before the present (6kyr BP). With the Earth's orbital parameters appropriate for the mid-Holocene, the IAP9L-AGCM computed warmer and wetter conditions in boreal summer than for the present day. Under the precondition of continental snow and glacier cover existing over part of the Tibetan Plateau at the mid-Holocene, the authors examined the regional climate response to the Tibetan Plateau cooling. The simulations indicated that climate changes in South Asia and parts of central Asia as well as in East Asia are sensitive to the Tibetan Plateau cooling at the mid-Holocene, showing a significant decrease in precipitation in northern India, northern China and southern Mongolia and an increase in Southeast Asia during boreal summer.The latter seems to correspond to the weakening, southeastward shift of the Asian summer monsoon system resulting from reduced heat contrast between the Eurasian continent and the Pacific and Indian Oceans when a cooling over the Tibetan Plateau was imposed. The simulation results suggest that the snow and glacier environment over the Tibetan Plateau is an important factor for mid-Holocene climate change in the areas highly influenced by the Asian monsoon.

  19. The occurrence and characterization of Campylobacter jejuni and C. coli in organic pigs and their outdoor environment

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Dalsgaard, Anders; Baggesen, Dorte Lau

    2006-01-01

    safety. Bacteriological methods for determination of Campylobacter excretion level were combined with colony-blot hybridization and real-time PCR for specific detection of C. jejuni in pigs. Campylobacter was isolated from pigs (n = 47), paddock environment (n = 126) and wildlife (n = 44), identified...... (0.3-46%). C. jejuni and C coli were isolated from 10% and 29% of the environmental samples, respectively, while crow-birds and rats harboured C. jejuni. Individual pigs hosted several strains (up to nine serotypes). The paddock environment was contaminated with C. coli serotypes similar to pig...

  20. Pollen record from red clay sequence in the central Loess Plateau between 8.10 and 2.60 Ma

    Institute of Scientific and Technical Information of China (English)

    MA Yuzhen; WU Fuli; FANG Xiaomin; LI Jijun; AN Zhisheng; WANG Wei

    2005-01-01

    The Late Miocene and Pliocene are the key periods for understanding the origin and development of the present Asian monsoon circulations and ecologic environments. Here we present a pollen record from Chaona Red Clay section located in the central Loess Plateau in attempt to establish the histories of vegetation and associated climate changes between 8.10 and 2.60 Ma. Our results show that Gramineae-dominated woodland-grasslands developed in this region with Cedrus- and Pinus-characterized montane coniferous forests distributing in higher elevations from 8.10 to 6.73 Ma, probably suggesting a semi-humid climate in a warm-temperate zone. A subsequent expansion of Ulmus- dominated deciduous forests and a synchronous increase of Gramineae-dominated grassland reflect a warmer and more humid climate between 6.73 and 5.67 Ma. The vegetation changed to an Artemisia- and Gramineae-characterized steppe in lower elevations and to a coniferous forest in higher elevations from 5.67 to 3.71 Ma, implying probably a warm and semiarid climate in lowland and hill, and a colder and moister climate in mountain. During this period, a considerable warmer and more humid climate occurred between 4.61 and 4.07 Ma as indicated by pollen assemblages. The period between 3.71 and 2.58 Ma was characterized by the disappearance of Cedrus and Tsuga and also by an abrupt expansion of Cupressaceae, reflecting a drastic enhancement of monsoon-related climatic seasonality.

  1. The impacts of urbanization on soil erosion in the Loess Plateau region

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The accelerated urbanization has resulted in new soil erosion inthe Loess Plateau region since the 1980s. A concept of urban erosion and its impacts on environment are discussed. The experimental studies and field investigations show that those loose silt and earth piles formed by urban construction can be eroded seriously: Under stormy rain, the amount of sediment from steep man-dumped slope is 10.8-12.2 times that of from uncovered slope land; the result of experiments with the wind tunnel also shows that the damage to the surface structure of dry loess can cause serious soil erosion by wind in some cities of the region. Even if in the urban built-up area, there are many loose sandy soil, mud and silt, which are washed into rivers by city's ground flow in the rainy season.So, anthropogenically induced soil erosion has made soil erosion more serious around the urban areas.And the urban eroded environment has several characteristics such as fragility, complexity,seasonality and quick variability. Urban areas witness a quick economic growth and have more construction projects than rural areas, which brings more intensive changes of environments during a short period of time or adds some new elements to the erosion system. Therefore erosion has experienced more intensive impact by human activities. So, the possible impact of urbanization on erosion environment must be taken into consideration when designing or planning to exploit natural rsources or to develop urban areas in the Loess Plateau.

  2. Methanogen Diversity in Indigenous and Introduced Ruminant Species on the Tibetan Plateau.

    Science.gov (United States)

    Huang, Xiao Dan; Martinez-Fernandez, Gonzalo; Padmanabha, Jagadish; Long, Ruijun; Denman, Stuart E; McSweeney, Christopher S

    2016-01-01

    Host factors are regarded as important in shaping the archaeal community in the rumen but few controlled studies have been performed to demonstrate this across host species under the same environmental conditions. A study was designed to investigate the structure of the methanogen community in the rumen of two indigenous (yak and Tibetan sheep) and two introduced domestic ruminant (cattle and crossbred sheep) species raised and fed under similar conditions on the high altitude Tibetan Plateau. The methylotrophic Methanomassiliicoccaceae was the predominant archaeal group in all animals even though Methanobrevibacter are usually present in greater abundance in ruminants globally. Furthermore, within the Methanomassiliicoccaceae family members from Mmc. group 10 and Mmc. group 4 were dominant in Tibetan Plateau ruminants compared to Mmc. group 12 found to be highest in other ruminants studied. Small ruminants presented the highest number of sequences that belonged to Methanomassiliicoccaceae compared to the larger ruminants. Although the methanogen community structure was different among the ruminant species, there were striking similarities between the animals in this environment. This indicates that factors such as the extreme environmental conditions and diet on the Tibetan Plateau might have a greater impact on rumen methanogen community compared to host differences.

  3. Methanogen Diversity in Indigenous and Introduced Ruminant Species on the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Xiao Dan Huang

    2016-01-01

    Full Text Available Host factors are regarded as important in shaping the archaeal community in the rumen but few controlled studies have been performed to demonstrate this across host species under the same environmental conditions. A study was designed to investigate the structure of the methanogen community in the rumen of two indigenous (yak and Tibetan sheep and two introduced domestic ruminant (cattle and crossbred sheep species raised and fed under similar conditions on the high altitude Tibetan Plateau. The methylotrophic Methanomassiliicoccaceae was the predominant archaeal group in all animals even though Methanobrevibacter are usually present in greater abundance in ruminants globally. Furthermore, within the Methanomassiliicoccaceae family members from Mmc. group 10 and Mmc. group 4 were dominant in Tibetan Plateau ruminants compared to Mmc. group 12 found to be highest in other ruminants studied. Small ruminants presented the highest number of sequences that belonged to Methanomassiliicoccaceae compared to the larger ruminants. Although the methanogen community structure was different among the ruminant species, there were striking similarities between the animals in this environment. This indicates that factors such as the extreme environmental conditions and diet on the Tibetan Plateau might have a greater impact on rumen methanogen community compared to host differences.

  4. Local adaptation of Gymnocypris przewalskii (Cyprinidae) on the Tibetan Plateau.

    Science.gov (United States)

    Zhang, Renyi; Ludwig, Arne; Zhang, Cunfang; Tong, Chao; Li, Guogang; Tang, Yongtao; Peng, Zuogang; Zhao, Kai

    2015-05-06

    Divergent selection among environments affects species distributions and can lead to speciation. In this article, we investigated the transcriptomes of two ecotypes of scaleless carp (Gymnocypris przewalskii przewalskii and G. p. ganzihonensis) from the Tibetan Plateau. We used a transcriptome sequencing approach to screen approximately 250,000 expressed sequence tags (ESTs) from the gill and kidney tissues of twelve individuals from the Ganzi River and Lake Qinghai to understand how this freshwater fish has adapted to an ecological niche shift from saline to freshwater. We identified 9,429 loci in the gill transcriptome and 12,034 loci in the kidney transcriptome with significant differences in their expression, of which 242 protein-coding genes exhibited strong positive selection (Ka/Ks > 1). Many of the genes are involved in ion channel functions (e.g., Ca(2+)-binding proteins), immune responses (e.g., nephrosin) or cellular water absorption functions (e.g., aquaporins). These results have potentially broad importance in understanding shifts from saline to freshwater habitats. Furthermore, this study provides the first transcriptome of G. przewalskii, which will facilitate future ecological genomics studies and aid in the identification of genes underlying adaptation and incipient ecological speciation.

  5. Evaluating the coupling effects of climate aridity and vegetation restoration on soil erosion over the Loess Plateau in China.

    Science.gov (United States)

    Zhang, Baoqing; He, Chansheng; Burnham, Morey; Zhang, Lanhui

    2016-01-01

    In this study, the coupling effects of climate aridity and vegetation restoration on runoff and sediment yield over the Loess Plateau were examined and characterized. To take into consideration the complexity of drought, as well as the varied strengths and weaknesses of different drought measures, two drought indices are selected to identify and evaluate drought variability. The Normalized Difference Vegetation Index (NDVI) data were obtained to monitor and express spatiotemporal variations in vegetation cover. The results show that most regions of the Loess Plateau experienced increasingly severe droughts over the past 40years, and these regions comprise the major source of the Yellow River sediment. Climatic drying initially occurred in the 1990s, and became statistically significant in 2000s. The increasingly severe droughts could negatively impact surface and groundwater supplies as well as soil water storage, but may also minimize surface runoff yield, which is one of the major causes of soil erosion on the Loess Plateau. Vegetation cover on the Loess Plateau was significantly improved after the implementation of "Grain for Green" project, which were helpful for controlling severe soil erosion. With the impacts of the construction of check dams, terraces and large reservoirs, runoff and sediment yield over the Loess Plateau initially exhibited downward trends between 1970 and 1990. After 1990, with the effects of the climate warming and drying, a second sharp reduction in runoff and sediment yield occurred. The coupling effects of climate aridity and vegetation restoration have led to a third significant decrease in runoff and sediment yield over the Loess Plateau after 2000.

  6. Characterization of the genetic environment of the blaKPC-2 gene among Klebsiella pneumoniae isolates from a Chinese Hospital.

    Science.gov (United States)

    Shen, Pinghua; Zhang, Ying; Li, Gang; Jiang, Xiaofei

    2016-01-01

    Infection caused by carbapenem-resistant Klebsiella pneumoniae has become a major healthcare threat and KPC-2 enzyme is a dominant factor mediating carbapenems resistance in K. pneumoniae. This study was designed to determine the genetic environment of blaKPC-2, which prevailed in clinical K. pneumoniae isolates recovered in Huashan Hospital, Shanghai, China. Forty-two clinical isolates were included in this study by blaKPC-2 screening. After multilocus sequence typing and plasmid analyses of PCR-based replicon typing (PBRT), junction PCR, mapping PCR and crossing PCR assays, primer walking, and amplicon sequencing were used to analyze the genetic environment of the blaKPC-2 gene. ST423, ST65, ST977, and ST11 were all detected in KPC-2-producing K. pneumoniae. Two types of blaKPC-2-bearing genetic structure were found: Tn1721-blaKPC-2-Tn3 and Tn1721-blaKPC-2-ΔTn3-IS26; and were carried in IncX and IncFII plasmids, respectively. In conclusion, the genetic environment of the blaKPC-2 gene was diverse and Tn1721-blaKPC-2-ΔTn3-IS26 was dominant in clinical K. pneumoniae isolates in Huashan Hospital. This study sheds some light on the genetic environment and should foster further studies about the mechanism of the blaKPC-2 dissemination.

  7. Thermal and geodynamic contributions to the elevation of the Altiplano-Puna plateau

    Science.gov (United States)

    Prezzi, Claudia; Iglesia Llanos, María Paula; Götze, Hans-Jürgen; Schmidt, Sabine

    2014-12-01

    The most remarkable feature of the Central Andes is the Altiplano-Puna plateau. This plateau is characterized by 3.5 km average elevation, approximately 70 km crustal thickness and very high heat flow. The upper mantle structure changes along strike below the plateau. The upper mantle below the Puna becomes hotter, and the lithosphere becomes thinner and weaker. These features suggest that thermal isostasy could play a role in the compensation of the Altiplano-Puna. Thermal isostasy is the geodynamic process whereby regional variations in the lithospheric thermal regime cause changes in elevation. Elevation changes result from variations in rock density in response to thermal expansion. The aim of this study is to estimate the thermal and geodynamic contributions to the elevation. While the thermal component of the Altiplano elevation would be of 1 km, the thermal contribution to the southern Puna elevation would be of 1.5 km. However, in the case of the southern Puna a portion of the actual topography (∼20%) cannot be explained considering only compositional and thermal effects, suggesting additional geodynamical support. The obtained results suggest that the thermal state of the lithosphere would play a significant role in the elevation of the Central Andes, and may be responsible of some of the geological differences displayed by the Altiplano and the Puna.

  8. Observations of A Low-Velocity Type II-Plateau Supernova 2013am in M65

    CERN Document Server

    Zhang, Jujia; Mazzali, Paolo A; Bai, Jinming; Zhang, Tianmeng; Bersier, David; Huang, Fang; Fan, Yufeng; Mo, Jun; Wang, Jianguo; Yi, Weimin; Wang, Chuanjun; Xin, Yuxin; Liangchang,; Zhang, Xiliang; Lun, Baoli; Wang, Xueli; He, Shousheng; Walker, Emma S

    2014-01-01

    Optical and ultraviolet observations for the nearby type II-plateau supernova (SN IIP) 2013am in the nearby spiral galaxy M65 are presented in this paper. The early spectra are characterized by relatively narrow P-Cygni features, with ejecta velocities much lower than observed in normal SNe IIP (i.e., $\\sim$2000 km s$^{-1}$ vs. $\\sim$5000 km $^{-1}$ in the middle of the plateau phase). Moreover, prominent \\ion{Ca}{2} absorptions are also detected in SN 2013am at relatively early phases. These spectral features are reminiscent of those seen in the low-velocity and low-luminosity SN IIP 2005cs. However, SN 2013am exhibits different photometric properties, having shorter plateau phases and brighter light-curve tails if compared to SN 2005cs. Adopting $R_{V}$=3.1 and a mean value of total reddening derived from the photometric and spectroscopic methods(i.e., $E(B-V)=0.55\\pm$0.19 mag), we find that SN 2013am may have reached an absolute $V$-band peak magnitude of $-15.83\\pm0.71$ mag and produced a $^{56}$Ni mass o...

  9. Mongolian plateau: Evidence for a late Cenozoic mantle plume under central Asia

    Science.gov (United States)

    Windley, Brian F.; Allen, Mark B.

    1993-04-01

    The 2500 x 700 km Mongolian plateau (average elevation 2000 m) is situated between the Altai orogen and the Siberian craton and occupies much of Mongolia and Transbaikalia in Russia. The plateau is characterized by (1) basin and range topography and two major domes(Hentai, 600 x 300 km, and Hangai, 800 x 550 km), where altitudes reach 3905 m; (2) lithosphere that is thinner than adjacent areas (minimum ˜50 km); (3) elevated heat flow (up to 120 mW/m2); (4) dominantly alkaline basaltic volcanism in the form of cones, lava fields, and volcanic plateaus mostly of Miocene-Quaternary age, and (5) rifts, including Baikal (main evolution in the Pliocene-Quaternary), Tunka (Oligocene-early Miocene), and Hobsogol (Pliocene-Quaternary). Existing models explain these features in terms of diapiric upwelling of a mantle asthenolith below the main rifts and/or as a long-distance effect of the India-Asia collision. We propose that the late Cenozoic uplift of the whole Mongolian plateau and associated rifting, magmatism, high heat flow, and lithospherec thinning are not externally driven by the India-Asia collision, but are the expression of the interaction of a mantle plume with overlying lithosphere. Some rifts link and interact with major strike-slip faults, such as the Bolnai. Such faults may be the major expression of the India-Asia collision in this region.

  10. Agrobiodiversity of cactus pear (Opuntia, Cactaceae in the Meridional Highlands Plateau of Mexico

    Directory of Open Access Journals (Sweden)

    Juan Antonio Reyes-Agüero

    2011-08-01

    Full Text Available Mexico is characterized by a remarkable richness of Opuntia, mostly at the Meridional Highlands Plateau; it is also here where the greatest richness of Opuntia variants occurs. Most of these variants have been maintained in homegardens; however, the gathering process which originated these homegardens has been disrupted over the past decades, as a result of social change and the destruction of large wild nopaleras. If the variants still surviving in homegardens are lost, these will be hard to recover, that is, the millenary cultural heritage from the human groups that populated the Mexican Meridional Highland Plateau will be lost forever. This situation motivated the preparation of a catalogue that records the diversity of wild and cultivated Opuntia variants living in the meridional Highlands Plateau. To this end, 379 samples were obtained in 29 localities, between 1998 and 2003. The information was processed through Twinspan. All specimens were identified and preserved in herbaria. Botanical keys and descriptions were elaborated. The catalogue includes information on 126 variants comprising 18 species. There were species with only one variant (Opuntia atropes, O. cochinera, O. jaliscana, O. leucotricha, O. rzedowskii and O. velutina, two (O. durangensis, O. lindheimeri, O. phaeacantha and O. robusta, five (O. joconostle and O. lasiacantha, seven (O. chavena, 12 (O. hyptiacantha and O. streptacantha, 15 (O. ficus-indica, 22 (O. albicarpa, and up to 34 (O. megacantha. Additionally, 267 common cactus pear names were related to those variants.

  11. Giant magnetoresistance, three-dimensional Fermi surface and origin of resistivity plateau in YSb semimetal

    Science.gov (United States)

    Pavlosiuk, Orest; Swatek, Przemysław; Wiśniewski, Piotr

    2016-12-01

    Very strong magnetoresistance and a resistivity plateau impeding low temperature divergence due to insulating bulk are hallmarks of topological insulators and are also present in topological semimetals where the plateau is induced by magnetic field, when time-reversal symmetry (protecting surface states in topological insulators) is broken. Similar features were observed in a simple rock-salt-structure LaSb, leading to a suggestion of the possible non-trivial topology of 2D states in this compound. We show that its sister compound YSb is also characterized by giant magnetoresistance exceeding one thousand percent and low-temperature plateau of resistivity. We thus performed in-depth analysis of YSb Fermi surface by band calculations, magnetoresistance, and Shubnikov-de Haas effect measurements, which reveals only three-dimensional Fermi sheets. Kohler scaling applied to magnetoresistance data accounts very well for its low-temperature upturn behavior. The field-angle-dependent magnetoresistance demonstrates a 3D-scaling yielding effective mass anisotropy perfectly agreeing with electronic structure and quantum oscillations analysis, thus providing further support for 3D-Fermi surface scenario of magnetotransport, without necessity of invoking topologically non-trivial 2D states. We discuss data implying that analogous field-induced properties of LaSb can also be well understood in the framework of 3D multiband model.

  12. "Mucientes Chert" in the Northern Iberian Plateau (Spain

    Directory of Open Access Journals (Sweden)

    M. Natividad Fuertes-Prieto

    2014-03-01

    Full Text Available The so-called “Mucientes chert" is a variety that appears in the central area of the Iberian North Plateau, in theDueroBasin. It is widely known in the geological and archaeological literature and its use for knapping was especially important in Prehistory. From a macroscopic point of view it is a nodular chert, with white and very porous cortex, and brown to blackish or beige colour in the inner part.In this work we carried out a more accurate petrographic, mineralogical and chemical characterization of this lithology using SEM, XRD and XRF techniques in samples coming from “Las Canteras” (Mucientes village, a chert outcrop of the “Cuestas” Unit (Vallesian-Aragonian, Miocene Age. Also, we have made a review of its geological occurrence and archaeological distribution areas.  It is intended to sketch the delimitation of the geographical area of occurrence taking into account the geological and archaeological references. 

  13. Lake-System Response to Late Quaternary Environmental Dynamics on the northeastern Tibetan Plateau

    Science.gov (United States)

    Diekmann, Bernhard; Hartmann, Kai; Herzschuh, Ulrike; Lehmkuhl, Frank; Mischke, Steffen; Stauch, Georg; Wünnemann, Bernd; Zhang, Yongshan

    2014-05-01

    fixation. Lake development is documented by multi-proxy data in a series of sediment cores across the lake basin. The oldest recovered sediments, younger than 18 ka BP, comprise siliciclastic laminates and lateglacial saline shallow-lake sediments, overlying basal sands. The deposition of fine-grained marls and enhanced biological production characterized the deep lacustrine environment of the Holocene. A switch from a closed lake basin with brackish conditions towards an open oligotrophic fresh-water basin after 6.8 ka BP is indicated by ostracod assemblages and changes in carbonate chemistry. This change in hydrology likely was triggered by tectonic pulses along the Kunlun Fault, an area with severe earthquake activity. Pollen records exhibit climate signals and indicate moist conditions in the early Holocene. During the same time, loess sediments have been preserved from a period from 10.5 to 7.5 ka BP, related to the strengthening of the insolation-driven Asian summer monsoons. This time was characterized by wetter and warmer climate and supported the trapping of dust. A dry and cooler climate resulted in the reactivation of dune sands from 3 ka to present, possibly in combination with stronger human influence.

  14. LA PRESENCIA DE CAMÉLIDOS EN EL AUSTRO ECUATORIANO: EVIDENCIA ARQUEOLÓGICA DE TEXTILERÍA EN LA MESETA DE PACHAMAMA (The Presence of Camelids in Southern Ecuador: Archaeological Evidence of Textile Industry on the Pachamama Plateau

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Novillo Verdugo

    2016-09-01

    Full Text Available La meseta de Pachamama (Azuay, Ecuador constituye un espacio de gran interés arqueológico pues los restos culturales en él registrados denotan actividades específicas de culturas prehispánicas asentadas en la región. De esta manera, el presente artículo resulta una primera aproximación a la caracterización de la actividad textilera en el área a partir de elementos como fusayolas, mandíbulas de camélidos, corrales, con el fin de discutir y aportar nuevos conocimientos históricos en el austro ecuatoriano. Se matiza el área de estudio como un escenario propicio para el desarrollo de flora y fauna, pues el recurso hídrico en la zona es permanente y se presenta en toda la extensión de la meseta. Esta característica es perceptible por los diferentes momentos en que fue ocupada la meseta de Pachamama, donde se construyeron sistemas de terracería y caminos que conectan diferentes áreas constituyendo una red vial. ENGLISH: The Pachamama Plateau (Azuay, Ecuador is an area of great archaeological interest, as it contains evidence regarding the specific activities of pre-Hispanic cultures in the region. This article is an initial approach to the characterization of textile-making activity in the area based on artifacts such as spindle whorls, camelid mandibles, and corrals, in order to provide new historical knowledge about southern Ecuador. The study area is a favorable environment for the development of flora and fauna, as it contains permanent water resources across the extent of plateau. This environmental scenario was similar during periods of past occupations of the Pachamama Plateau, where terraces and roads were built to connect different areas, constituting a road network.

  15. Wetlands sediment record from the upper Yarlung Tsangpo valley, southwest Tibetan Plateau, reveals mid-Holocene Epipaleolithic human occupation coincident with increased early and mid-Holocene wetness driven by enhanced Indian Monsoon rainfall

    Science.gov (United States)

    Hudson, A. M.; Olsen, J. W.; Quade, J.; Lei, G.; Huth, T.; Zhang, H.; Perreault, C.

    2016-12-01

    The headwaters of the Yarlung Tsangpo river valley, located in the southwestern Tibetan Plateau, are characterized by a cold and dry climate, but contain abundant river-marginal wetlands environments, which fluctuate in extent in response to changes in local water table elevation. This region receives 80% of precipitation from the Indian Monsoon, which forms the dominant control on moisture availability, and hence wetlands extent. Our paleowetlands record, based on 14C dating of organic-rich paleowetlands deposits, provides a novel record of Holocene monsoon intensity. The wetlands deposits consist of four sedimentary units that indicate decreasing wetlands extent and monsoon intensity since 10.4 ka BP. Wet conditions occurred at ˜10.4 ka BP, ˜9.6 ka BP and ˜7.9-4.8 ka BP, with similar-to-modern conditions from ˜4.6-2.0 ka BP, and drier-than-modern conditions from ˜2.0 ka BP to present. Wetland changes correlate with monsoon intensity changes identified in nearby records, with weak monsoon intervals corresponding to desiccation and erosion of wetlands deposits. Dating of in situ ceramic and microlithic artifacts in wetlands sediments at multiple sites indicates Epipaleolithic human occupation of the YT valley after 6.6 ka BP. Artifact typology study reveals a similar microlithic technology was employed across the high plateau interior, but XRF obsidian provenance reveals separate northeast and southwest lithic conveyance zones. This indicates widespread colonization of the high, arid Tibetan Plateau interior by one or more highly mobile human populations during the early and mid-Holocene, coincident with favorable warm, wet climate conditions.

  16. Characterization of NDM-1- and OXA-23-producing Acinetobacter baumannii isolates from inanimate surfaces in a hospital environment in Algeria.

    Science.gov (United States)

    Zenati, K; Touati, A; Bakour, S; Sahli, F; Rolain, J M

    2016-01-01

    Investigation of several outbreaks of multidrug-resistant Acinetobacter baumannii infection has demonstrated that contamination of the inanimate hospital environment could be implicated in the spread of these multidrug-resistant strains. To investigate the occurrence of carbapenem-resistant A. baumannii on inanimate surfaces and possible dissemination in the hospital environment in Algeria as a potential source of infection in humans. A. baumannii strains were isolated from the hospital environment and identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined using disc diffusion and E-test methods. Carbapenemase activity was detected using microbiological tests, including modified Hodge test, modified Carba NP test, and EDTA test. Carbapenem resistance determinants were studied by polymerase chain reaction (PCR) and sequencing. Clonal relatedness was determined using multi-locus sequence typing (MLST). A total of 67 A. baumannii isolates were obtained from 868 environmental samples and identified by MALDI-TOF MS. Among them, 61 isolates were resistant to imipenem with minimum inhibitory concentration >32 μg/mL and positive by the modified Hodge test and modified Carba NP test. In addition, the activity of carbapenemase was inhibited by EDTA in 32 strains. PCR and sequencing showed the presence of blaOXA-23 gene in 29 strains, and the blaNDM-1 gene in 32 isolates. MLST demonstrated the presence of five types of ST (ST19, ST2, ST85, ST98, and ST115). Our study demonstrated the dissemination of carbapenemase-producing A. baumannii strains recovered from inanimate surfaces in a hospital environment, surrounding patients, healthcare workers and visitors, in Algeria as a potential source for nosocomial infection. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  17. Optical and photochemical characterization of chromophoric dissolved organic matter from lakes in Terra Nova Bay, Antarctica. Evidence of considerable photoreactivity in an extreme environment.

    Science.gov (United States)

    De Laurentiis, Elisa; Buoso, Sandro; Maurino, Valter; Minero, Claudio; Vione, Davide

    2013-12-17

    Water samples from shallow lakes located in Terra Nova Bay, Antarctica, were taken in the austral summer season and characterized for chemical composition, optical features, fluorescence excitation-emission matrix (EEM) and photoactivity toward the generation of (•)OH, (1)O2, and (3)CDOM* (triplet states of chromophoric dissolved organic matter). The optical properties suggested that CDOM would be largely of aquagenic origin and possibly characterized by limited photochemical processing before sampling. Moreover, the studied samples were highly photoactive and the quantum yields for the generation of (3)CDOM* and partially of (1)O2 and (•)OH were considerably higher compared to water samples from temperate environments. This finding suggests that water in the studied lakes would have considerable ability to photosensitize the degradation of dissolved compounds during the austral summer, possibly including organic pollutants, also considering that the irradiance conditions of the experiments were not far from those observed on the Antarctic coast during the austral summer.

  18. Research on Key Point of the Design of Plateau Power Supply Car Electrical Control Sector%高原电源车电气控制部分设计要点研究

    Institute of Scientific and Technical Information of China (English)

    朱逸天; 孙默圆; 陈熙霖

    2015-01-01

    高原环境由于其特殊性,使装备电气控制部分的电气特性受到了影响,本文针对这个问题结合有关资料总结了高原电源车的电气设计要点。%Because of the particularity of plateau environment, the electrical control sector of plateau power supply car is under the influence. To address this problem, this paper summarize the key point of the design of plateau power supply car electrical control sector combine with related material.

  19. COLD AND HEAT WAVES IN THE BARLAD PLATEAU BETWEEN 1961-2013

    Directory of Open Access Journals (Sweden)

    M.C. HUSTIU

    2016-03-01

    Full Text Available Among the meteorological phenomena with severe impact upon individual humans, upon society and the environment one distinguishes cold and heat waves. The geographic location of the Bârlad Plateau – east of the mountainous barrier of the Eastern Carpathians and in a region where main pressure centers travel along the year – facilitates the occurrence of cold and heat waves. Such events were analysed, for the interval 1961-2013, both as the frequency of massive warming and cooling situations, and their duration – taking as a reference intervals of at least 5 consecutive days when in any month thermal anomalies are recorded, either positive or negative.

  20. Total knee arthroplasty and fractures of the tibial plateau

    Science.gov (United States)

    Softness, Kenneth A; Murray, Ryan S; Evans, Brian G

    2017-01-01

    Tibial plateau fractures are common injuries that occur in a bimodal age distribution. While there are various treatment options for displaced tibial plateau fractures, the standard of care is open reduction and internal fixation (ORIF). In physiologically young patients with higher demand and better bone quality, ORIF is the preferred method of treating these fractures. However, future total knee arthroplasty (TKA) is a consideration in these patients as post-traumatic osteoarthritis is a common long-term complication of tibial plateau fractures. In older, lower demand patients, ORIF is potentially less favorable for a variety of reasons, namely fixation failure and the need for delayed weight bearing. In some of these patients, TKA can be considered as primary mode of treatment. This paper will review the literature surrounding TKA as both primary treatment and as a salvage measure in patients with fractures of the tibial plateau. The outcomes, complications, techniques and surgical challenges are also discussed.

  1. Phylogeography of regional fauna on the Tibetan Plateau: A review

    Institute of Scientific and Technical Information of China (English)

    Shujuan Yang; Hailiang Dong; Fumin Lei

    2009-01-01

    The studies of uplift and glaciations of the Tibetan Plateau are summarized, and a series of recent case studies of the endemic species based on DNA sequences are detailed. In general, these molecular data show that all the organisms originated from Early Pliocene to Late Miocene, and then multi-stages of divergence/speciation occurred within each taxa following their original occupation on the pla-teau, mainly as a result of periodic glacial cycles and geographic isolation. The regional fauna may have undergone several range con-tractions and expansions during the Pleistocene glaciations. However, the population expansion and refugia may vary in space, time, and extent. The regional fauna of the Tibetan Plateau may be combinations of ancient movement from adjacent zoogeographical regions, speciation in situ, and postglacial colonization from adjacent areas. Geomorphic and climatic changes on the plateau definitely have a remarkable influence on the regional and adjacent biogeographic patterns, and the mechanism is very complex.

  2. The Colorado Plateau coal assessment study area, 2000 (cpstdyg)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This is a coverage of the Colorado Plateau coal assessment study area. The study area outline was drawn on the county lines that most closely outline the...

  3. Flora investigation kicks off on Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Coordinated by the CAS Kunming Institute of Botany,a project to investigate the floral germplasm resources on the Qinghai-Tibet Plateau was initiated recently in Kunming,capital of southwest China's Yunnan Province.

  4. Review and proposals on vegetation restoration in the Loess Plateau, Northwest China

    Institute of Scientific and Technical Information of China (English)

    Wenhui ZHANG; Guobin LIU

    2008-01-01

    A group of scientists conducted a comprehen-sive investigation on ecological safety and water and soil erosion in the Northwest Loess Plateau, Northwest China. The data gathered was analyzed in terms of achievement, existing problems, and strategy and mea-sures on vegetation restoration in the area. Since the policies of conversion from cropland to forest (CCF) and forbid grazing and cutting (FGC) were carried out, vegetation quality and coverage rate increased quickly in the Loess Plateau area, strengthening the concept of eco-environment protection. Environment harness measure-ments were optimized. The multiform investments on eco-environment and urbanization development in China will benefit vegetation restoration. However, there have been some persisting problems, such as the shortage of investment, instability of government policy, expectation of extravagant economic benefit, larger rate of planta-tion, and scarce technologies supporting vegetation restoration. Many key theories and practice problems require an urgent resolution. In the future, short-, mid-,and long-term goals for vegetation restoration should be clear, achievement should be expanded, and the natural restoration area should be increased. The benefit for the contractor on vegetation restoration should be ensured. Investment on vegetation building research work should be increased.

  5. Tibetan plateau aridification linked to global cooling at the Eocene-Oligocene transition.

    Science.gov (United States)

    Dupont-Nivet, Guillaume; Krijgsman, Wout; Langereis, Cor G; Abels, Hemmo A; Dai, Shuang; Fang, Xiaomin

    2007-02-08

    Continental aridification and the intensification of the monsoons in Asia are generally attributed to uplift of the Tibetan plateau and to the land-sea redistributions associated with the continental collision of India and Asia, whereas some studies suggest that past changes in Asian environments are mainly governed by global climate. The most dramatic climate event since the onset of the collision of India and Asia is the Eocene-Oligocene transition, an abrupt cooling step associated with the onset of glaciation in Antarctica 34 million years ago. However, the influence of this global event on Asian environments is poorly understood. Here we use magnetostratigraphy and cyclostratigraphy to show that aridification, which is indicated by the disappearance of playa lake deposits in the northeastern Tibetan plateau, occurred precisely at the time of the Eocene-Oligocene transition. Our findings suggest that this global transition is linked to significant aridification and cooling in continental Asia recorded by palaeontological and palaeoenvironmental changes, and thus support the idea that global cooling is associated with the Eocene-Oligocene transition. We show that, with sufficient age control on the sedimentary records, global climate can be distinguished from tectonism and recognized as a major contributor to continental Asian environments.

  6. The Colorado Plateau II : Biophysical, Socioeconomic, and Cultural Research

    OpenAIRE

    Van Riper, Charles; Mattson, David J.

    2005-01-01

    Abstract from GoogleBooks: The publication of The Colorado Plateau: Cultural, Biological, and Physical Research in 2004 marked a timely summation of current research in the Four Corners states. This new volume, derived from the seventh Biennial Conference on the Colorado Plateau in 2003, complements the previous book by again focusing on the integration of science into resource management issues. The 32 chapters range in content from measuring human impacts on cultural resources, through graz...

  7. The Colorado Plateau II : Biophysical, Socioeconomic, and Cultural Research

    OpenAIRE

    Van Riper, Charles; Mattson, David J.

    2005-01-01

    Abstract from GoogleBooks: The publication of The Colorado Plateau: Cultural, Biological, and Physical Research in 2004 marked a timely summation of current research in the Four Corners states. This new volume, derived from the seventh Biennial Conference on the Colorado Plateau in 2003, complements the previous book by again focusing on the integration of science into resource management issues. The 32 chapters range in content from measuring human impacts on cultural resources, through graz...

  8. AHP 21: Pyramid Schemes on the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Devin Gonier

    2017-09-01

    Full Text Available The unique features of pyramid shemes and certain underlying causes for their development on the Tibetan Plateau are analyzed. Research was conducted by analyzing 521 surveys, allowing estimation of pyramid scheme activity on the Plateau and an identification of related cultural and social specificities. Firsthand accounts were collected revealing details of personal involvement. Survey data and similarities in the accounts were studied to suggest how involvement in pyramid schemes might be reduced at both institutional and individual levels.

  9. Evolution of the Ordos Plateau and environmental effects

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the analysis of temporary-spatial distribution, geomorphic position, contact relationship with underlying strata and grain size of red clay, we studied the formation and environmental background of red clay. During late Miocene-Pliocene, the Ordos Block finished the transformation from the basin to the plateau, which had an obvious environmental effect on the topography, indicated by the formation of highland undergoing wind erosion and lowland receiving red clay deposits. The red clay materials were sourced from dusts carried by wind energy and covered on the initial topography. Unlike Quaternary loess dust covering the overall the Loess Plateau, red clay deposited on the highland would be transported to the lowlands by wind and fluvial process. As a result, there was no continuous "Red Clay Plateau" in the Ordos region and red clay was only preserved in former lowlands. However, red clay was discontinuously distributed through the Loess Plateau and to some extent modified the initial topography. The differential uplift in interior plateau is indicated by the uplift of northern Baiyushan, central Ziwuling and southern Weibeibeishan. The Weibeibeishan Depression formed earlier and became the sedimentary center of red clay resulting in the thicker red clay deposits in Chaona, Lingtai and Xunyi. Since Quaternary the aridity in the northern plateau enhanced and accelerated loess accumulation caused the formation of the Loess Plateau. During the late Pleistocene the rapid uplift led to the enhancement of erosion. Especially after the cut-through of Sanme Lake by the Yellow River, the decline of base level caused the falling of ground water level and at the same time the increase of drainage density resulting in the enhancement of evaporation capacity, which enhanced the aridity tendency of aridity in the Loess Plateau region.

  10. 兰坪—思茅盆地与呵叻高原钾盐矿床综合对比%Comprehensive Comparison of Potash Deposits in Lanping-Simao Basin and Khorat Plateau

    Institute of Scientific and Technical Information of China (English)

    韩元红; 马海州; 袁小龙; 张西营; 高东林

    2011-01-01

    云南兰坪—思茅盆地与泰国-老挝呵叻高原处于同一构造带,两者在钾盐成矿及成因各方面都有着很大的相似性.通过对兰坪—思茅盆地与呵叻高原成矿地质背景、成盐时代、成盐物源和环境、沉积和地球化学特征等多方面对比分析,系统阐述了二者的异同,重点强调了存在的差异性,提出了一些今后开展工作的意见和建议.%Khorat plateau is located in northeast Thailand and middle Lao' s, with the world's largest potash deposits. These deposits are characterized by shallow burying and great thickness. Lanping-Simao basin in China lies in the same tectonic zone with Khorat plateau. There are geat similarities in original and mineralization in two areas. Focused on the comparative studies on geological setting, evaporation time, provenance and environment, sedimentary characteristics, Br geochemistry and other aspects, the similarities especially differences were systemically analyzed between two areas. At last, some valuable suggests have been put forward for the further work in these areas.

  11. Depositional environment, organic matter characterization and hydrocarbon potential of Middle Miocene sediments from northeastern Bulgaria (Varna-Balchik Depression

    Directory of Open Access Journals (Sweden)

    Zdravkov Alexander

    2015-10-01

    Full Text Available The depositional environments and hydrocarbon potential of the siliciclastic, clayey and carbonate sediments from the Middle Miocene succession in the Varna-Balchik Depression, located in the south-eastern parts of the Moesian Platform, were studied using core and outcrop samples. Based on the lithology and resistivity log the succession is subdivided from base to top into five units. Siliciclastic sedimentation prevailed in the lower parts of units I and II, whereas their upper parts are dominated by carbonate rocks. Unit III is represented by laminated clays and biodetritic limestone. Units IV and V are represented by aragonitic sediments and biomicritic limestones, correlated with the Upper Miocene Topola and Karvuna Formations, respectively. Biogenic silica in the form of diatom frustules and sponge spicules correlates subunit IIa and unit III to the lower and upper parts of the Middle Miocene Euxinograd Formation. Both (subunits contain organic carbon contents in the order of 1 to 2 wt. % (median: 0.8 for subunit IIa; 1.3 for unit III, locally up to 4 wt. %. Based on Hydrogen Index values (HI and alkane distribution pattern, the kerogen is mainly type II in subunit IIa (average HI= 324 mg HC/g TOC and type III in unit III (average HI ~200 mg HC/g TOC. TOC and Rock Eval data show that subunit IIa holds a fair (to good hydrocarbon generative potential for oil, whereas the upper 5 m of unit III holds a good (to fair potential with the possibility to generate gas and minor oil. The rocks of both units are immature in the study area. Generally low sulphur contents are probably due to deposition in environments with reduced salinity. Normal marine conditions are suggested for unit III. Biomarker composition is typical for mixed marine and terrestrial organic matter and suggests deposition in dysoxic to anoxic environments.

  12. Quantitative Assessment of Desertification Using Landsat Data on a Regional Scale – A Case Study in the Ordos Plateau, China

    Directory of Open Access Journals (Sweden)

    Jianjun Pan

    2009-03-01

    Full Text Available Desertification is a serious threat to the ecological environment and social economy in our world and there is a pressing need to develop a reasonable and reproducible method to assess it at different scales. In this paper, the Ordos Plateau in China was selected as the research region and a quantitative method for desertification assessment was developed by using Landsat MSS and TM/ETM+ data on a regional scale. In this method, NDVI, MSDI and land surface albedo were selected as assessment indicators of desertification to represent land surface conditions from vegetation biomass, landscape pattern and micrometeorology. Based on considering the effects of vegetation type and time of images acquired on assessment indictors, assessing rule sets were built and a decision tree approach was used to assess desertification of Ordos Plateau in 1980, 1990 and 2000. The average overall accuracy of three periods was higher than 90%. The results showed that although some local places of Ordos Plateau experienced an expanding trend of desertification, the trend of desertification of Ordos Plateau was an overall decrease in from 1980 to 2000. By analyzing the causes of desertification processes, it was found that climate change could benefit for the reversion of desertification from 1980 to 1990 at a regional scale and human activities might explain the expansion of desertification in this period; however human conservation activities were the main driving factor that induced the reversion of desertification from 1990 to 2000.

  13. The seismic wave speed structure of the Ontong Java Plateau determined from joint ambient noise and earthquake waveform data

    Science.gov (United States)

    Covellone, B. M.; Savage, B. K.; Shen, Y.

    2014-12-01

    The Ontong Java Plateau (OJP) represents the result of a significant event in the Earth's geologic history. Limited geophysical and geochemical data, as well as the plateau's relative isolation in the Pacific Ocean, have made interpretation of the modern day geologic structure and its 120 Ma formation history difficult. Here we present the highest resolution images to date of the wave speed structure of the OJP region. We use an iterative finite-frequency tomography methodology and a unique data set that combines empirical Green's functions extracted from ambient noise and earthquake waveforms. The uniqueness and combination of datasets allow us to best exploit the limited station distribution in the Pacific and image wave speed structures between 35 km and greater than 250 km into the Earth. We image a region of fast shear wave speeds, greater than 4.75 km/s, that extends to greater than 100 km beneath the plateau. The wave speeds are similar to as observed in cratonic environments and are consistent with a compositional anomaly likely a result of eclogite entrainment during the plateau's formation.

  14. Nutrient Lossed in Soils on Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    PENGLIN; WANGJI-ZENG; 等

    1995-01-01

    The soil nutrient losses due to excessive soil loss on Loess Plateau were studied by means of runoff plots and systematical determination of soil nutrients both in sediments and runoff.The results show that the amounts of nutrient losses depended on the amounts of ersoion sediments.Along with sediment,11-197kg nitrogen/hectare and 9-174kg phosphorus/hectare were lost,accounting for 92.46-99.47 percent of the total amount of nitrogen loss and 99.85-99.99 percent of the total amount of phosphorus loss respectively.The nutrient losses,very small in runoff,were mainly attributed to erosion of a few rainstorms during a year.The nutrient level in sediment was mostly higher than that in the original soil.Planting grass evidently redued the losses of soil nutrients.The N level was lower in runoff than in rainfall so that the N loss from runoff could be made up by rainfall.Fertilizer application to crops raised the nutrient level in runoff.

  15. Solution of the Kirchhoff-Plateau Problem

    Science.gov (United States)

    Giusteri, Giulio G.; Lussardi, Luca; Fried, Eliot

    2017-01-01

    The Kirchhoff-Plateau problem concerns the equilibrium shapes of a system in which a flexible filament in the form of a closed loop is spanned by a liquid film, with the filament being modeled as a Kirchhoff rod and the action of the spanning surface being solely due to surface tension. We establish the existence of an equilibrium shape that minimizes the total energy of the system under the physical constraint of noninterpenetration of matter, but allowing for points on the surface of the bounding loop to come into contact. In our treatment, the bounding loop retains a finite cross-sectional thickness and a nonvanishing volume, while the liquid film is represented by a set with finite two-dimensional Hausdorff measure. Moreover, the region where the liquid film touches the surface of the bounding loop is not prescribed a priori. Our mathematical results substantiate the physical relevance of the chosen model. Indeed, no matter how strong is the competition between surface tension and the elastic response of the filament, the system is always able to adjust to achieve a configuration that complies with the physical constraints encountered in experiments.

  16. Post-rift volcanic structures of the Pernambuco Plateau, northeastern Brazil

    Science.gov (United States)

    Buarque, Bruno V.; Barbosa, José A.; Magalhães, José R. G.; Cruz Oliveira, Jefferson T.; Filho, Osvaldo J. Correia

    2016-10-01

    The Pernambuco marginal basin is located on the eastern continental margin of northeastern Brazil, covers an area of 20,800 km2, and represents one of the most prominent frontiers for deep water oil and gas exploration off the Brazilian coast. The onshore region of this basin was highly affected by extrusive and intrusive magmatism during the Upper Albian, and the relation of that event with the volcanic structures observed in the offshore sector has not been thoroughly characterized to date. This study aims to characterize the major extrusive and intrusive volcanic structures of the offshore portion of this basin, which is dominated by the Pernambuco Plateau, and its stratigraphic relations. A set of 143 2D multichannel seismic sections that cover the Pernambuco Plateau region are used to interpret the major tectono-stratigraphic sequences and describe the distribution of volcanoes, sills, vent complexes and related volcaniclastic sequences. The interpretations are supported by aeromagnetic and gravimetric geophysical surveys. Volcanoes are classified into two groups that differ in terms of their morphology: shield-like structures and cone-shaped volcanic structures. Sill intrusions are mainly identified beneath the volcanic structures and are characterized by high-amplitude reflectors with short extensions and abrupt terminations. Volcaniclastic sequences are found adjacent to the volcanoes and are characterized by high-amplitude, disrupted reflections with local chaotic configurations. Vent complexes are classified on the basis of their morphologies as either eye-shaped or crater-shaped. The volcanic features identified within the available seismic dataset are concentrated in two main areas: in the centre of the plateau and near its northeastern border. These two regions are host basement outer highs and are surrounded by hyper-extended continental crust, which forms the plateau itself. The extrusive and intrusive features described in the offshore region were

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

    Science.gov (United States)

    Duan, Anmin; Xiao, Zhixiang

    2015-09-02

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

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

    Science.gov (United States)

    Duan, Anmin; Xiao, Zhixiang

    2015-01-01

    The surface air temperature change over the Tibetan Plateau is determined based on historical observations from 1980 to 2013. In contrast to the cooling trend in the rest of China, and the global warming hiatus post-1990s, an accelerated warming trend has appeared over the Tibetan Plateau during 1998–2013 (0.25 °C decade−1), compared with that during 1980–1997 (0.21 °C decade−1). Further results indicate that, to some degree, such an accelerated warming trend might be attributable to cloud–radiation feedback. The increased nocturnal cloud over the northern Tibetan Plateau would warm the nighttime temperature via enhanced atmospheric back-radiation, while the decreased daytime cloud over the southern Tibetan Plateau would induce the daytime sunshine duration to increase, resulting in surface air temperature warming. Meanwhile, the in situ surface wind speed has recovered gradually since 1998, and thus the energy concentration cannot explain the accelerated warming trend over the Tibetan Plateau after the 1990s. It is suggested that cloud–radiation feedback may play an important role in modulating the recent accelerated warming trend over the Tibetan Plateau. PMID:26329678

  19. A fast-multipole domain decomposition integral equation solver for characterizing electromagnetic wave propagation in mine environments

    KAUST Repository

    Yücel, Abdulkadir C.

    2013-07-01

    Reliable and effective wireless communication and tracking systems in mine environments are key to ensure miners\\' productivity and safety during routine operations and catastrophic events. The design of such systems greatly benefits from simulation tools capable of analyzing electromagnetic (EM) wave propagation in long mine tunnels and large mine galleries. Existing simulation tools for analyzing EM wave propagation in such environments employ modal decompositions (Emslie et. al., IEEE Trans. Antennas Propag., 23, 192-205, 1975), ray-tracing techniques (Zhang, IEEE Tran. Vehic. Tech., 5, 1308-1314, 2003), and full wave methods. Modal approaches and ray-tracing techniques cannot accurately account for the presence of miners and their equipments, as well as wall roughness (especially when the latter is comparable to the wavelength). Full-wave methods do not suffer from such restrictions but require prohibitively large computational resources. To partially alleviate this computational burden, a 2D integral equation-based domain decomposition technique has recently been proposed (Bakir et. al., in Proc. IEEE Int. Symp. APS, 1-2, 8-14 July 2012). © 2013 IEEE.

  20. Virulence repertoire, characterization, and antibiotic resistance pattern analysis of Escherichia coli isolated from backyard layers and their environment in India.

    Science.gov (United States)

    Samanta, Indranil; Joardar, Siddhartha N; Das, Pradip K; Das, Palas; Sar, Tapas K; Dutta, Tapan K; Bandyopadhyay, Samiran; Batabyal, Subhasis; Isore, Devi P

    2014-03-01

    This study was undertaken to observe the prevalence, serogroup, avian pathogenic Escherichia coli (APEC)-associated virulence gene, randomly amplified polymorphic DNA (RAPD) pattern, and antibiotic resistance genes of E. coli in backyard layers and their environment in India. From the 360 samples of healthy layers and their environment, 272 (75.5%) E. coli were isolated. The majority (28.67%) of them were untypeable. Among the studied virulence genes (papC, tsh, iucC, astA), 52 (14.32%) isolates were found to possess astA, including the isolates from the drinking water of the birds (4/272, 1.47%). These strains belonged to 18 different serogroups. Most of the isolates were typeable by RAPD and they produced different patterns. Phenotypic resistance of the isolates was most frequently observed to erythromycin (95.83%), chloramphenicol (87.52%), and cotrimoxazole (78.26%). None of the isolates was found to possess extended-spectrum beta-lactamases (bla(TEM), bla(SHV), bla(CTX-M) or quinolone resistance (qnrA) genes by PCR. The present study was the first attempt in India to assess APEC distribution in backyard poultry production.

  1. Space Shuttle Main Engine Low Pressure Oxidizer Turbo-Pump Inducer Dynamic Environment Characterization through Water Model and Hot-Fire Testing

    Science.gov (United States)

    Arellano, Patrick; Patton, Marc; Schwartz, Alan; Stanton, David

    2006-01-01

    The Low Pressure Oxidizer Turbopump (LPOTP) inducer on the Block II configuration Space Shuttle Main Engine (SSME) experienced blade leading edge ripples during hot firing. This undesirable condition led to a minor redesign of the inducer blades. This resulted in the need to evaluate the performance and the dynamic environment of the redesign, relative to the current configuration, as part of the design acceptance process. Sub-scale water model tests of the two inducer configurations were performed, with emphasis on the dynamic environment due to cavitation induced vibrations. Water model tests were performed over a wide range of inlet flow coefficient and pressure conditions, representative of the scaled operating envelope of the Block II SSME, both in flight and in ground hot-fire tests, including all power levels. The water test hardware, facility set-up, type and placement of instrumentation, the scope of the test program, specific test objectives, data evaluation process and water test results that characterize and compare the two SSME LPOTP inducers are discussed. In addition, dynamic characteristics of the two water models were compared to hot fire data from specially instrumented ground tests. In general, good agreement between the water model and hot fire data was found, which confirms the value of water model testing for dynamic characterization of rocket engine turbomachinery.

  2. The role of climatic and anthropogenic stresses on long-term runoff reduction from the Loess Plateau, China.

    Science.gov (United States)

    Feng, Xiaoming; Cheng, Wei; Fu, Bojie; Lü, Yihe

    2016-11-15

    Human intervention has strongly altered patterns of river runoff. Yet, few studies have addressed the complexity and nonlinearity of the anthropogenic stresses on runoff or their interaction with climate. We study the Loess Plateau in China, whose river runoff contributes 65% of the discharge to the middle reach of the Yellow River; this landscape has been shaped by human activity and is intensively managed. Our purpose is to characterize the interactive roles of climate and human activities in defining river runoff from the Loess Plateau. Applying a transient analysis to discover the time-varying runoff trend and impact factors, we found that the average runoff in the Loess Plateau decreased continuously during the period 1961-2009 (average rate of -0.9mmyear(-1), Prunoff mainly occurred in three stages, with transitions in 1970, 1981 and 1996. Reduced precipitation was the main reason for the decrease in runoff over the entire study period. However, human intervention played a dominant role in creating the transition points. Water yield (i.e., the ratio of runoff to precipitation) decreased following each anthropogenic transition, causing a 56% reduction in available freshwater resources during the period 1961-2009. These findings highlight the need for studies that address the dynamic and nonlinear processes controlling the availability of freshwater resources in the light of anthropogenic influences applied under a changing climate. Such studies are essential if we are to meet the human water demand in the Loess Plateau region.

  3. Ultra-robust high-field magnetization plateau and supersolidity in bond-frustrated MnCr2S4

    Science.gov (United States)

    Tsurkan, Vladimir; Zherlitsyn, Sergei; Prodan, Lilian; Felea, Viorel; Cong, Pham Thanh; Skourski, Yurii; Wang, Zhe; Deisenhofer, Joachim; von Nidda, Hans-Albrecht Krug; Wosnitza, Joahim; Loidl, Alois

    2017-01-01

    Frustrated magnets provide a promising avenue for realizing exotic quantum states of matter, such as spin liquids and spin ice or complex spin molecules. Under an external magnetic field, frustrated magnets can exhibit fractional magnetization plateaus related to definite spin patterns stabilized by field-induced lattice distortions. Magnetization and ultrasound experiments in MnCr2S4 up to 60 T reveal two fascinating features: (i) an extremely robust magnetization plateau with an unusual spin structure and (ii) two intermediate phases, indicating possible realizations of supersolid phases. The magnetization plateau characterizes fully polarized chromium moments, without any contributions from manganese spins. At 40 T, the middle of the plateau, a regime evolves, where sound waves propagate almost without dissipation. The external magnetic field exactly compensates the Cr–Mn exchange field and decouples Mn and Cr sublattices. In analogy to predictions of quantum lattice-gas models, the changes of the spin order of the manganese ions at the phase boundaries of the magnetization plateau are interpreted as transitions to supersolid phases. PMID:28345038

  4. Characterization of the thermolysis products of Nafion membrane: A potential source of perfluorinated compounds in the environment

    Science.gov (United States)

    Feng, Mingbao; Qu, Ruijuan; Wei, Zhongbo; Wang, Liansheng; Sun, Ping; Wang, Zunyao

    2015-05-01

    The thermal decomposition of Nafion N117 membrane, a typical perfluorosulfonic acid membrane that is widely used in various chemical technologies, was investigated in this study. Structural identification of thermolysis products in water and methanol was performed using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). The fluoride release was studied using an ion-chromatography system, and the membrane thermal stability was characterized by thermogravimetric analysis. Notably, several types of perfluorinated compounds (PFCs) including perfluorocarboxylic acids were detected and identified. Based on these data, a thermolysis mechanism was proposed involving cleavage of both the polymer backbone and its side chains by attack of radical species. This is the first systematic report on the thermolysis products of Nafion by simulating its high-temperature operation and disposal process via incineration. The results of this study indicate that Nafion is a potential environmental source of PFCs, which have attracted growing interest and concern in recent years. Additionally, this study provides an analytical justification of the LC/ESI-MS/MS method for characterizing the degradation products of polymer electrolyte membranes. These identifications can substantially facilitate an understanding of their decomposition mechanisms and offer insight into the proper utilization and effective management on these membranes.

  5. Genetic diversity of Mycobacterium avium isolates recovered from clinical samples and from the environment: molecular characterization for diagnostic purposes.

    Science.gov (United States)

    Alvarez, Julio; García, Ignacio Gómez; Aranaz, Alicia; Bezos, Javier; Romero, Beatriz; de Juan, Lucía; Mateos, Ana; Gómez-Mampaso, Enrique; Domínguez, Lucas

    2008-04-01

    Isolation of Mycobacterium avium complex (MAC) organisms from clinical samples may occur in patients without clinical disease, making the interpretation of results difficult. The clinical relevance of MAC isolates from different types of clinical samples (n = 47) from 39 patients in different sections of a hospital was assessed by comparison with environmental isolates (n = 17) from the hospital. Various methods for identification and typing (commercial probes, phenotypic characteristics, PCR for detection of IS1245 and IS901, sequencing of the hsp65 gene, and pulsed-field gel electrophoresis) were evaluated. The same strain was found in all the environmental isolates, 21 out of 23 (91.3%) of the isolates cultured from urine samples, and 5 out of 19 (26.3%) isolates from respiratory specimens. This strain did not cause disease in the patients. Testing best characterized the strain as M. avium subsp. hominissuis, with the unusual feature that 81.4% of these isolates lacked the IS1245 element. Contamination of certain clinical samples with an environmental strain was the most likely event; therefore, characterization of the environmental mycobacteria present in health care facilities should be performed to discard false-positive isolations in nonsterile samples, mainly urine samples. Molecular techniques applied in this study demonstrated their usefulness for this purpose.

  6. A new application for analyzing driving behaviour and environment characterization in transportation systems based on a fuzzy logic approach

    Science.gov (United States)

    Fazio, Peppino; Santamaria, Amilcare Francesco; De Rango, Floriano; Tropea, Mauro; Serianni, Abdon

    2016-05-01

    In the last years the physical security in transportation systems is becoming a critical issue due to the high number of accidents and emergency situations. With the increasing availability of technological applications in vehicular environments researchers aimed at minimizing the probability of road accidents. In this paper, we propose a new platform able to discover dangerous driving behaviors. We based our application on the on-board diagnosis standard, able to provide all the needed information directly from the electronic vehicle control unit . We integrated the received data with a fuzzy logic approach, obtaining a description of the driver behavior. The overall system can take several initiatives (alarms, rpm corrections, etc.), in order to notify the driver bad behavior. The performance of the proposed scheme has been validated through a deep campaign of driving simulations.

  7. Characterization of 17-4 PH stainless steel foam for biomedical applications in simulated body fluid and artificial saliva environments.

    Science.gov (United States)

    Mutlu, Ilven; Oktay, Enver

    2013-04-01

    Highly porous 17-4 PH stainless steel foam for biomedical applications was produced by space holder technique. Metal release and weight loss from 17-4 PH stainless steel foams was investigated in simulated body fluid and artificial saliva environments by static immersion tests. Inductively coupled plasma-mass spectrometer was employed to measure the concentrations of various metal ions released from the 17-4 PH stainless steel foams into simulated body fluids and artificial saliva. Effect of immersion time and pH value on metal release and weight loss in simulated body fluid and artificial saliva were determined. Pore morphology, pore size and mechanical properties of the 17-4 PH stainless steel foams were close to human cancellous bone. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. NMR characterization of the C-terminal tail of full-length RAGE in a membrane mimicking environment

    Energy Technology Data Exchange (ETDEWEB)

    Borsi, Valentina; Cerofolini, Linda; Fragai, Marco; Luchinat, Claudio, E-mail: luchinat@cerm.unifi.it [University of Florence, Magnetic Resonance Center (CERM) (Italy)

    2012-11-15

    Targeting the receptor for the advanced glycation endproducts (RAGE) signalling has a potential for the prevention and treatment of several pathologies. Extracellular activation of RAGE triggers the interactions of the RAGE cytoplasmic tail with intracellular protein partners. Here the cytoplasmic tail of RAGE has been investigated by NMR as part of the full-length protein, in the presence of a membrane-mimicking environment. The isolated cytoplasmic tail has also been studied for comparison. The NMR spectra of the whole receptor show that some but not all residues belonging to the C-terminal region of the cytoplasmic tail have a large flexibility, while the membrane proximal region seems to be rigidly connected to the trans-membrane domain and ectodomains. The analysis indicates that the behavior of the cytoplasmic tail is strongly affected by its being part of the whole receptor. These results provide new insight towards the understanding of signal transduction by RAGE.

  9. 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.

  10. Status, ecology, and conservation of the Himalayan griffon Gyps himalayensis (Aves, Accipitridae) in the Tibetan plateau.

    Science.gov (United States)

    Lu, Xin; Ke, Dianhua; Zeng, Xianhai; Gong, Guohong; Ci, Ren

    2009-05-01

    The dramatic population crashes of 3 species of Gyps vulture have raised concerns about the status of their lesser-known congeners. Among these is the Himalayan griffon, G. himalayensis, an iconic vulture of the Tibetan plateau. The continued existence of this scavenger has not only ecological but also cultural implications because of their unique role in the centuries-old sky burial tradition that is followed by nearly 5 million Tibetan people. A lack of baseline information of the Himalayan griffon limits our ability to take conservation measures. The presented data, which were collected during 1996 and 2004 to 2007, indicate that this species is still widespread throughout the plateau and has not experienced a major population decline, likely as a result of protection by Tibetan Buddhism and limited disturbances from human activities largely due to the remoteness of the plateau. Both site and road counts showed that open meadow habitats had the highest griffon abundance, followed by alpine shrub and forest habitats. Estimates based on road transect counts showed that 229,339 Himalayan griffons (+/- 40,447) occupy the 2.5 million km2 Tibetan plateau. In contrast, the maximum carrying capacity of the plateau, on the basis of the total biomass of potential food resources, is 507,996 griffons, with meadow habitats accounting for about 76% of the total population. Griffons depend largely on livestock carcasses for food and forage in groups averaging 5.5 (range 1-100) individuals. Domestic yaks provide about 64% of the griffons' diet, while wild ungulates and human corpses provide 1% and 2%, respectively. Compared with its lowland congeners, this, the only high-elevation Gyps species, had both low population density and small group size, a likely response to the harsh environmental conditions. Although griffon abundance appears relatively stable in their fairly pristine environment, precautionary measures, including investigation of threats, monitoring of population

  11. 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

  12. Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    WANG; Genxu; LI; Yuanshou

    2006-01-01

    Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage,grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the permafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment.Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the Iow mountain and plateau area will have a relatively

  13. Continued Research into Characterizing the Preturbulence Environment for Sensor Development, New Hazard Algorithms and Experimental Flight Planning

    Science.gov (United States)

    Kaplan, Michael L.; Lin, Yuh-Lang

    2005-01-01

    The purpose of the research was to develop and test improved hazard algorithms that could result in the development of sensors that are better able to anticipate potentially severe atmospheric turbulence, which affects aircraft safety. The research focused on employing numerical simulation models to develop improved algorithms for the prediction of aviation turbulence. This involved producing both research simulations and real-time simulations of environments predisposed to moderate and severe aviation turbulence. The research resulted in the following fundamental advancements toward the aforementioned goal: 1) very high resolution simulations of turbulent environments indicated how predictive hazard indices could be improved resulting in a candidate hazard index that indicated the potential for improvement over existing operational indices, 2) a real-time turbulence hazard numerical modeling system was improved by correcting deficiencies in its simulation of moist convection and 3) the same real-time predictive system was tested by running the code twice daily and the hazard prediction indices updated and improved. Additionally, a simple validation study was undertaken to determine how well a real time hazard predictive index performed when compared to commercial pilot observations of aviation turbulence. Simple statistical analyses were performed in this validation study indicating potential skill in employing the hazard prediction index to predict regions of varying intensities of aviation turbulence. Data sets from a research numerical model where provided to NASA for use in a large eddy simulation numerical model. A NASA contractor report and several refereed journal articles where prepared and submitted for publication during the course of this research.

  14. Chemical and physical characterization of traffic particles in four different highway environments in the Helsinki metropolitan area

    Science.gov (United States)

    Enroth, Joonas; Saarikoski, Sanna; Niemi, Jarkko; Kousa, Anu; Ježek, Irena; Močnik, Griša; Carbone, Samara; Kuuluvainen, Heino; Rönkkö, Topi; Hillamo, Risto; Pirjola, Liisa

    2016-05-01

    Traffic-related pollution is a major concern in urban areas due to its deleterious effects on human health. The characteristics of the traffic emissions on four highway environments in the Helsinki metropolitan area were measured with a mobile laboratory, equipped with state-of-the-art instrumentation. Concentration gradients were observed for all traffic-related pollutants, particle number (CN), particulate mass (PM1), black carbon (BC), organics, and nitrogen oxides (NO and NO2). Flow dynamics in different environments appeared to be an important factor for the dilution of the pollutants. For example, the half-decay distances for the traffic-related CN concentrations varied from 8 to 83 m at different sites. The PM1 emissions from traffic mostly consisted of organics and BC. At the most open site, the ratio of organics to BC increased with distance to the highway, indicating condensation of volatile and semi-volatile organics on BC particles. These condensed organics were shown to be hydrocarbons as the fraction of hydrocarbon fragments in organics increased. Regarding the CN size distributions, particle growth during the dilution was not observed; however the mass size distributions measured with a soot particle aerosol mass spectrometer (SP-AMS), showed a visible shift of the mode, detected at ˜ 100 nm at the roadside, to a larger size when the distance to the roadside increased. The fleet average emission factors appeared to be lower for the CN and higher for the NO2 than ten years ago. The reason is likely to be the increased fraction of light-duty (LD) diesel vehicles in the past ten years. The fraction of heavy-duty (HD) traffic, although constituting less than 10 % of the total traffic flow, was found to have a large impact on the emissions.

  15. Norhla: Restoring the glory of khullu wool for social development and environmental protection in the High Tibetan Plateau

    OpenAIRE

    Guesné, Jean-Marc; Michaut-Denizeau, Anne; Sireyjol, Alice

    2012-01-01

    For centuries, the local communities of yaks’ transhumant cattle farmers of the Tibetan High plateau have lived on their yak breeding activity, providing them with all they need: milk, a source of butter and cheese, and hair, which they weave into the heavy black tents that characterize the nomadic population. In the last decade, however, changes occurred that have destabilized this activity. The changes are three-fold: (1) increasing economic difficulty to live from this activity (Melvyn et ...

  16. The Neogene tectonic evolution and climatic change of the Tianshui Basin, NE Tibetan Plateau

    Science.gov (United States)

    Peng, T.; Li, J.; Song, C.; Zhao, Z.; Zhang, J.; Wang, X.; Hui, Z.

    2013-12-01

    The Tianshui Basin, located at the conjunction of NE Tibetan Plateau and Chinese Loess Plateau, has received intensive attention recently. Fine-grained Miocene sediment was identified as loess in its north part and this pushes the onset of Asian aridification into 22 Ma. However, our sedimentological, biomarker, pollen, diatom and mammalian fossils evidence propose that these sediments were suggested to be mudflat/distal fan and floodplain deposit instead of eolian deposit. So detailed tectonic background and climate reconstruction may illustrate the controversy and shed light on the tectonic, climate and ecology interactions. Here we report our integrated studies on the tectonic evolution, climate change and paleoecology reconstruction in the Tianshui basin. Based on the magnetostratigraphy and fossil mammal ages, sedimentological and detrital fission-track thermochronologic (DFT) analysis reveals four episodic tectonic uplift events occurred at ~20 Ma, ~14 Ma, ~9.2-7.4 Ma and ~3.6 Ma along the basin and its adjacent mountains. The timing of these activities at Western Qinling have been documented at many segments of the Tibetan Plateau, so most likely they were the remote response to the ongoing India-Asia collision. Pollen, mammalian fossils and biomarker data permit us to illustrate the paleoenvironment in the Tianshui Basin. During the period of ~17-10 Ma, the climate was generally warm-humid revealed by the broad-leaved forest and low Average Chain Length (ACL) values, when the Paltybelodon and Gomphotherium were roaming near an extensive aquatic setting. In addition, the observed Middle Miocene Climatic Optimum and Middle Miocene Climatic Transition events may be a terrestrial response to global climate changes. During the interval of ~10-6 Ma, the climate was relatively arid characterized by the rapid development of steppe and appearance of the Hipparion fauna, consistent with the biomarker proxy. Although the NE Tibetan Plateau experienced a phase of

  17. Distinct Network Interactions in Particle-Associated and Free-Living Bacterial Communities during a Microcystis aeruginosa Bloom in a Plateau Lake

    Directory of Open Access Journals (Sweden)

    Caiyun Yang

    2017-06-01

    Full Text Available Particle-associated bacteria (PAB and free-living bacteria (FLB from aquatic environments during phytoplankton blooms differ in their physical distance from algae. Both the interactions within PAB and FLB community fractions and their relationship with the surrounding environmental properties are largely unknown. Here, by using high-throughput sequencing and network-based analyses, we compared the community and network characteristics of PAB and FLB from a plateau lake during a Microcystis aeruginosa bloom. Results showed that PAB and FLB differed significantly in diversity, structure and microbial connecting network. PAB communities were characterized by highly similar bacterial community structure in different sites, tighter network connections, important topological roles for the bloom-causing M. aeruginosa and Alphaproteobacteria, especially for the potentially nitrogen-fixing (Pleomorphomonas and algicidal bacteria (Brevundimonas sp.. FLB communities were sensitive to the detected environmental factors and were characterized by significantly higher bacterial diversity, less connectivity, larger network size and marginal role of M. aeruginosa. In both networks, covariation among bacterial taxa was extensive (>88% positive connections, and bacteria potentially affiliated with biogeochemical cycling of nitrogen (i.e., denitrification, nitrogen-fixation and nitrite-oxidization were important in occupying module hubs, such as Meganema, Pleomorphomonas, and Nitrospira. These findings highlight the importance of considering microbial network interactions for the understanding of blooms.

  18. Aftershock Decay Rates in the Iranian Plateau

    Science.gov (United States)

    Ommi, S.; Zafarani, H.; Zare, M.

    2016-07-01

    Motivated by the desire to have more information following the occurrence of damaging events, the main purpose of this article is to study aftershock sequence parameters in the Iranian plateau. To this end, the catalogue of the Iranian earthquakes between 2002 to the end of 2013 has been collected and homogenized among which 15 earthquakes have been selected to study their aftershock decay rates. For different tectonic provinces, the completeness magnitudes ( M c) of the earthquake catalogue have been calculated in different time intervals. Also, the M c variability in spatial and temporal windows has been determined for each selected event. For major Iranian earthquakes, catalogue of aftershocks has been collected thanks to three declustering methods: first, the classical windowing method of Gardner and Knopoff (Bull Seismol Soc Am 64:1363-1367, 1974); second, a modified version of this using spatial windowing based on the Wells and Coppersmith (Bull Seismol Soc Am 84:974-1002, 1994) relations; and third, the Burkhard and Grünthal (Swiss J Geosci 102:149-188, 2009) scheme. Effects of the temporal windows also have been investigated using the time periods of 1 month, 100 days, and 1 year in the declustering method of Gardner and Knopoff (Bull Seismol Soc Am 64:1363-1367, 1974). In the next step, the modified Omori law coefficients have been calculated for the 15 selected earthquakes. The calibrated regional generic model describing the temporal and magnitude distribution of aftershocks is of interest for time-dependent seismic hazard forecasts. The regional characteristics of the aftershock decay rates have been studied for the selected Iranian earthquakes in the Alborz, Zagros and Central Iran regions considering their different seismotectonics regimes. However, due to the lack of sufficient data, no results have been reported for the Kopeh-Dagh and Makran seismotectonic regions.

  19. Characterizing and predicting species distributions across environments and scales: Argentine ant occurrences in the eye of the beholder

    Science.gov (United States)

    Menke, S.B.; Holway, D.A.; Fisher, R.N.; Jetz, W.

    2009-01-01

    Aim: Species distribution models (SDMs) or, more specifically, ecological niche models (ENMs) are a useful and rapidly proliferating tool in ecology and global change biology. ENMs attempt to capture associations between a species and its environment and are often used to draw biological inferences, to predict potential occurrences in unoccupied regions and to forecast future distributions under environmental change. The accuracy of ENMs, however, hinges critically on the quality of occurrence data. ENMs often use haphazardly collected data rather than data collected across the full spectrum of existing environmental conditions. Moreover, it remains unclear how processes affecting ENM predictions operate at different spatial scales. The scale (i.e. grain size) of analysis may be dictated more by the sampling regime than by biologically meaningful processes. The aim of our study is to jointly quantify how issues relating to region and scale affect ENM predictions using an economically important and ecologically damaging invasive species, the Argentine ant (Linepithema humile). Location: California, USA. Methods: We analysed the relationship between sampling sufficiency, regional differences in environmental parameter space and cell size of analysis and resampling environmental layers using two independently collected sets of presence/absence data. Differences in variable importance were determined using model averaging and logistic regression. Model accuracy was measured with area under the curve (AUC) and Cohen's kappa. Results: We first demonstrate that insufficient sampling of environmental parameter space can cause large errors in predicted distributions and biological interpretation. Models performed best when they were parametrized with data that sufficiently sampled environmental parameter space. Second, we show that altering the spatial grain of analysis changes the relative importance of different environmental variables. These changes apparently result

  20. Amplitude of climatic changes in Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    On the basis of ice core and meteorological data from the Qinghai-Tibetan (Q-T) Plateau, this article focuses on the discussion of the problems related to the sensitivity of temporal and spatial changes of the climate in high-altitude regions, particularly in the Q-T Plateau. The features of abrupt climatic changes of the past 100 ka, 2 000 a and recent years indicate that the amplitude of these changes in the Q-T Plateau was obviously larger than that in low-altitude regions. The scope of temperature change above 6 000 m in the Q-T Plateau between glacial and interglacial stages could reach over 10℃, but only about 4℃ in low-elevation regions close to sea level. During the last 2 000 a, the amplitude of temperature changes at Guliya (over 6 000 m a.s.l.) in the Q-T Plateau reached 7℃, in comparison with 2℃ in eastern China at low altitude. In the present age, apparent differences of climatic warming have been observed in the Q-T Plateau, indicating that the warming in high-elevation regions is much higher than that in low-elevation regions. The temperature in over 3 500 m regions of the Q-T Plateau have been increasing at a rate of 0.25×10-1/a in recent 30 years, but almost no change has taken place in the regions below 500 m. Thus, we concluded that high-altitude regions are more sensitive to climatic changes than the low-altitude regions.

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

    Science.gov (United States)

    Mattson, David J.; van Riper, Charles

    2005-01-01

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

  2. Characterization of interfacial reactions and oxide films on 316L stainless steel in various simulated PWR primary water environments

    Science.gov (United States)

    Chen, Junjie; Xiao, Qian; Lu, Zhanpeng; Ru, Xiangkun; Peng, Hao; Xiong, Qi; Li, Hongjuan

    2017-06-01

    The effect of water chemistry on the electrochemical and oxidizing behaviors of 316L SS was investigated in hydrogenated, deaerated and oxygenated PWR primary water at 310 °C. Water chemistry significantly influenced the electrochemical impedance spectroscopy parameters. The highest charge-transfer resistance and oxide-film resistance occurred in oxygenated water. The highest electric double-layer capacitance and constant phase element of the oxide film were in hydrogenated water. The oxide films formed in deaerated and hydrogenated environments were similar in composition but different in morphology. An oxide film with spinel outer particles and a compact and Cr-rich inner layer was formed in both hydrogenated and deaerated water. Larger and more loosely distributed outer oxide particles were formed in deaerated water. In oxygenated water, an oxide film with hematite outer particles and a porous and Ni-rich inner layer was formed. The reaction kinetics parameters obtained by electrochemical impedance spectroscopy measurements and oxidation film properties relating to the steady or quasi-steady state conditions in the time-period of measurements could provide fundamental information for understanding stress corrosion cracking processes and controlling parameters.

  3. Characterizations of volatile organic compounds (VOCs) from vehicular emissions at roadside environment: The first comprehensive study in Northwestern China

    Science.gov (United States)

    Li, Bowei; Ho, Steven Sai Hang; Xue, Yonggang; Huang, Yu; Wang, Liqin; Cheng, Yan; Dai, Wenting; Zhong, Haobin; Cao, Junji; Lee, Shuncheng

    2017-07-01

    Vehicular emission (VE) is one of the important anthropogenic sources for ground-level volatile organic compounds (VOCs) in both urban and suburban areas. A first comprehensive campaign was conducted at an urban roadside in Xi'an, China in summer, 2016. A total of 57 VOCs, as known as critical surface ozone (O3) precursors, and other trace gases were measured simultaneously during the sampling period. Iso-pentane, a tracer of gasoline evaporation, was the most abundant VOC in the roadside samples, followed by isobutane and benzene, attributed to the largest composition (∼70%) of gasoline-fueled vehicles on the road. The molar ratio of toluene/benzene (T/B) in our study (0.36) is far lower than the range reported in other cities, indicating the stronger contributions from diesel emissions. The results of source apportionment achieved with positive matrix factorization (PMF) receptor model were highly consistent with the vehicles compositions, strongly evidenced that the precise characterization of the VE sources from those marker species. The degrees of individual compound contributed to O3 production were weighed by ozone formation potential (OFP). Propylene (20%), 1-butene (11%) and iso-pentane(10%) were the top three contributors at the roadside. The information of this study complements the VOCs database regarding to the VE sources in Northwestern China.

  4. Emplacement Scenarios for Vallis Schroteri, Aristarchus Plateau, the Moon

    Science.gov (United States)

    Garry, W. Brent; Bleacher, Jacob E.

    2011-01-01

    The volcanic processes that formed Vallis Schr teri are not well understood. Vallis Schr teri, located on the Aristarchus Plateau, is the largest rille on the Moon, and it displays three key morphologic components: the Cobra Head, the 155-km-long primary rille, and the 240-km-long inner rille. Observations of terrestrial eruptions are applied here to help explain the morphologic relationships observed for Vallis Schr teri. The Cobra Head, a 10-km-wide source vent surrounded by a 35-kmdiameter and 900-m-high low shield, might have been constructed from fl ows, spatter, and pyroclastic deposits erupted during lava fountain events, similar to the early stages of the vent at Pu u O o in Hawaii and the fi nal morphology of Bandera crater, a cinder cone in New Mexico. The vent fed an initial sheet fl ow controlled by preeruption topography. A channel formed within this sheet fl ow was the foundation for the primary rille, which deepened through construction and thermomechanical erosion by lava. The inner rille is confi ned to the fl at fl oor of the primary rille and is characterized by tight gooseneck meanders. This rille crosscuts the distal scarp of the primary rille and extends toward Oceanus Procellarum. This enigmatic relationship can be explained through backup, overfl ow, and diversion of the lava into a new rille that eroded into the margin of the primary rille. Similar backup, overfl ow, and redirection of the lava fl ow were observed during the 1984 Mauna Loa eruption in Hawaii. Analysis of the fi nal morphology of lunar rilles provides key information about lunar volcanic processes and insight into the local stratigraphy.

  5. Characterizing hydrophobicity of amino acid side chains in a protein environment via measuring contact angle of a water nanodroplet on planar peptide network.

    Science.gov (United States)

    Zhu, Chongqin; Gao, Yurui; Li, Hui; Meng, Sheng; Li, Lei; Francisco, Joseph S; Zeng, Xiao Cheng

    2016-11-15

    Hydrophobicity of macroscopic planar surface is conventionally characterized by the contact angle of water droplets. However, this engineering measurement cannot be directly extended to surfaces of proteins, due to the nanometer scale of amino acids and inherent nonplanar structures. To measure the hydrophobicity of side chains of proteins quantitatively, numerous parameters were developed to characterize behavior of hydrophobic solvation. However, consistency among these parameters is not always apparent. Herein, we demonstrate an alternative way of characterizing hydrophobicity of amino acid side chains in a protein environment by constructing a monolayer of amino acids (i.e., artificial planar peptide network) according to the primary and the β-sheet secondary structures of protein so that the conventional engineering measurement of the contact angle of a water droplet can be brought to bear. Using molecular dynamics simulations, contact angles θ of a water nanodroplet on the planar peptide network, together with excess chemical potentials of purely repulsive methane-sized Weeks-Chandler-Andersen solute, are computed. All of the 20 types of amino acids and the corresponding planar peptide networks are studied. Expectedly, all of the planar peptide networks with nonpolar amino acids are hydrophobic due to θ [Formula: see text] 90°, whereas all of the planar peptide networks of the polar and charged amino acids are hydrophilic due to θ [Formula: see text] 90°. Planar peptide networks of the charged amino acids exhibit complete-wetting behavior due to θ [Formula: see text] 0°. This computational approach for characterization of hydrophobicity can be extended to artificial planar networks of other soft matter.

  6. Characterization and Feasibility Assessment of Recycled Paper Mill Sludges for Land Application in Relation to the Environment

    Directory of Open Access Journals (Sweden)

    Rosazlin Abdullah

    2015-08-01

    Full Text Available The disposal of industrial paper mill sludge waste is a big issue and has a great importance all over the world. A study was conducted to determine the chemical properties of recycled paper mill sludge (RPMS and assess its possibilities for land application. RPMS samples were collected from six different paper mills in Malaysia and analyzed for physical and chemical properties, heavy metals, polycyclic aromatic hydrocarbons, 13C-NMR spectra and for the presence of dioxins/furans. The RPMS was dewatered, sticky with a strong odour, an average moisture of 65.08%, pH 7.09, cation exchange capacity (CEC 14.43 cmol (+ kg–1, N 1.45, P 0.18, K 0.12, Ca 0.82, Mg 0.73, Na 0.76 and Al, 1.38%. The polycyclic aromatic hydrocarbons (PAHs and heavy metals levels were below the standard Class 2 limits. The dioxin and furan were in below the standard concentration of Class 1. The most prominent peak in the 13C-NMR spectra of RPMS was centered at 31 ppm, proving the presence of methylene (-CH2 groups in long aliphatic chains, with lipids and proteins. The signal at 89 ppm and highly shielded shoulder at 83 ppm were due to presence of cellulose carbon C-4, and the peak at 63 and 65 ppm was due to the cellulose carbon spectrum. The RPMS therefore contains significant amount of nutrients with safe levels of heavy metals and PAHs for environment and can be used as a fertilizer and soil amendment for land application.

  7. Characterization and Feasibility Assessment of Recycled Paper Mill Sludges for Land Application in Relation to the Environment.

    Science.gov (United States)

    Abdullah, Rosazlin; Ishak, Che Fauziah; Kadir, Wan Rasidah; Bakar, Rosenani Abu

    2015-08-01

    The disposal of industrial paper mill sludge waste is a big issue and has a great importance all over the world. A study was conducted to determine the chemical properties of recycled paper mill sludge (RPMS) and assess its possibilities for land application. RPMS samples were collected from six different paper mills in Malaysia and analyzed for physical and chemical properties, heavy metals, polycyclic aromatic hydrocarbons, (13)C-NMR spectra and for the presence of dioxins/furans. The RPMS was dewatered, sticky with a strong odour, an average moisture of 65.08%, pH 7.09, cation exchange capacity (CEC) 14.43 cmol (+) kg(-1), N 1.45, P 0.18, K 0.12, Ca 0.82, Mg 0.73, Na 0.76 and Al, 1.38%. The polycyclic aromatic hydrocarbons (PAHs) and heavy metals levels were below the standard Class 2 limits. The dioxin and furan were in below the standard concentration of Class 1. The most prominent peak in the (13)C-NMR spectra of RPMS was centered at 31 ppm, proving the presence of methylene (-CH2) groups in long aliphatic chains, with lipids and proteins. The signal at 89 ppm and highly shielded shoulder at 83 ppm were due to presence of cellulose carbon C-4, and the peak at 63 and 65 ppm was due to the cellulose carbon spectrum. The RPMS therefore contains significant amount of nutrients with safe levels of heavy metals and PAHs for environment and can be used as a fertilizer and soil amendment for land application.

  8. Characterization and Feasibility Assessment of Recycled Paper Mill Sludges for Land Application in Relation to the Environment

    Science.gov (United States)

    Abdullah, Rosazlin; Ishak, Che Fauziah; Kadir, Wan Rasidah; Bakar, Rosenani Abu

    2015-01-01

    The disposal of industrial paper mill sludge waste is a big issue and has a great importance all over the world. A study was conducted to determine the chemical properties of recycled paper mill sludge (RPMS) and assess its possibilities for land application. RPMS samples were collected from six different paper mills in Malaysia and analyzed for physical and chemical properties, heavy metals, polycyclic aromatic hydrocarbons, 13C-NMR spectra and for the presence of dioxins/furans. The RPMS was dewatered, sticky with a strong odour, an average moisture of 65.08%, pH 7.09, cation exchange capacity (CEC) 14.43 cmol (+) kg–1, N 1.45, P 0.18, K 0.12, Ca 0.82, Mg 0.73, Na 0.76 and Al, 1.38%. The polycyclic aromatic hydrocarbons (PAHs) and heavy metals levels were below the standard Class 2 limits. The dioxin and furan were in below the standard concentration of Class 1. The most prominent peak in the 13C-NMR spectra of RPMS was centered at 31 ppm, proving the presence of methylene (-CH2) groups in long aliphatic chains, with lipids and proteins. The signal at 89 ppm and highly shielded shoulder at 83 ppm were due to presence of cellulose carbon C-4, and the peak at 63 and 65 ppm was due to the cellulose carbon spectrum. The RPMS therefore contains significant amount of nutrients with safe levels of heavy metals and PAHs for environment and can be used as a fertilizer and soil amendment for land application. PMID:26262636

  9. Gravitational salt tectonics above a rising basement plateau offshore Algeria

    Science.gov (United States)

    Gaullier, Virginie; Vendeville, Bruno C.; Besème, Grégoire; Legoux, Gaetan; Déverchère, Jacques; Lymer, Gaël

    2017-04-01

    Seismic data (survey "MARADJA 1", 2003) offshore the Algerian coast have imaged an unexpected deformation pattern of the Messinian salt (Mobile Unit; MU) and its sedimentary overburden (Messinian Upper Unit and Plio-Quaternary) above an actively rising plateau in the subsalt basement. From a geodynamic point of view, the region is undergoing crustal convergence, as attested by the Boumerdes earthquake (2003, magnitude 6.8). The rise of this plateau, forming a 3D promontory restricted to the area offshore Algiers, is associated with that geodynamic setting. The seismic profiles show several subsalt thrusts (Domzig et al. 2006). The data provided additional information on the deformation of the Messinian mobile evaporitic unit and its Plio-Quaternary overburden. Margin-perpendicular profiles show mostly compressional features (anticlines and synclines) that had little activity during Messinian times, then grew more during Plio-Quaternary times. A few normal faults are also present, but are not accompanied by salt rise. By contrast, margin-parallel profiles clearly show that extensional, reactive salt diapiric ridges (symptomatic with their triangular shape in cross section) formed early, as early as the time of deposition of the Messinian Upper Unit, as recorded by fan-shaped strata. These ridges have recorded E-W, thin-skinned gravity gliding above the Messinian salt, as a response to the rise of the basement plateau. We tested this hypothesis using two analogue models, one where we assumed that the rise of the plateau started after Messinian times (initially tabular salt across the entire region), the second model assumed that the plateau had already risen partially as the Messininan Mobile Unit was deposited (salt initially thinner above the plateau than in the adjacent regions). In both experiments, the rise of the plateau generated preferential E-W extension above the salt, combined with N-S shortening. Extension was caused by gravity gliding of the salt from

  10. Isolation and characterization of multifunctional Streptomyces species with antimicrobial, nematicidal and phytohormone activities from marine environments in Egypt.

    Science.gov (United States)

    Rashad, Ferial M; Fathy, Hayam M; El-Zayat, Ayatollah S; Elghonaimy, Ahlam M

    2015-06-01

    Different strategies have been employed for selective isolation of Streptomycetes from 20 marine samples varied in their biological nature. The recovery of Streptomycetes isolates (112) was influenced preferentially by different strategies; sediment samples were the best source of potential candidate Streptomycetes. All isolates exhibited antimicrobial activities with variable spectrum; the most promising isolates (31) were phenotypically characterized and identified as Streptomyces sp.; these isolates exhibited variable capacity for secretion of numerous hydrolytic enzymes such as catalase, protease, amylase, lipase, lecithinase, asparaginase, chitinase and pectinase. All the strains resisted both penicillin and streptomycin, 29 were sensitive to neomycin; the majority of strains (25) showed multiple antibiotic resistance index greater than 0.2; 23, 22 and 13 degraded the shrimp shell, chicken feather and corn cob, respectively, producing bioactive substance(s) which indicates their diversity and their ecological role in the marine ecosystem. At least 28 strains exhibited nematicidal activity in vitro and in vivo against root-knot nematode and supported plant growth. In vitro, the assessed Streptomyces species exhibited the ability to produce gibberellic acid, indole acetic acid, abscisic acid, kinetin and benzyladenine. Except for indole acetic acid, this is the first report concerning the ability of marine Streptomyces to produce such phytohormones and the use of shrimp shell waste as a mono component medium for production of phytohormones. The study is efficacious in selecting effective biodiverse strains of marine Streptomyces that may work under diverse agro-ecological conditions as a useful element in plant nutrition and as biocontrol agents involved in integrated management programs.

  11. Characterization of the association between 8q24 and colon cancer: gene-environment exploration and meta-analysis

    Directory of Open Access Journals (Sweden)

    Wallace Robert

    2010-12-01

    Full Text Available Abstract Background Genome-wide association studies and subsequent replication studies have shown that single nucleotide polymorphisms (SNPs in the chromosomal region 8q24 are associated with colorectal cancer susceptibility. Methods We examined 11 SNP markers in the 8q24 region between 128.47 and 128.54 Mb, using a total of 1,987 colon cases and 2,339 controls who self-reported as white from two independent, well-characterized study populations. Analysis was performed separately within each study, and combined using random effects meta-analysis. Logistic regression was used to estimate odds ratios (ORs and 95% confidence intervals (95% CIs and to test for effect modification by known colon cancer risk factors. We also performed a meta-analysis combining our results with previous studies. Results We observed evidence of association for four SNPs in low to high linkage disequilibrium (r2 ranging from 0.18 to 0.93 localized in a 16.2 kb region defined by rs10505477 and rs1056368. The combined results for our two studies of colon cancer showed an OR of 1.10 (95% CI: 1.01-1.20, Ptrend = 0.023, and a meta-analysis of our results with previously reported studies of colon and colorectal cancer strongly support the association for this SNP (combined OR for rs6983267 = 1.21, 95% CI: 1.18-1.24, p = 5.5 × 10-44. We did not observe any notable evidence of effect modification by known colon cancer risk factors, and risk did not differ significantly by tumor site or stage. Conclusions Our study confirms the association between polymorphisms on chromosome 8q24 and colon cancer risk and suggests that the susceptibility locus in region 8q24 is not strongly modified by various lifestyle, environmental, and demographic risk factors for colon cancer.

  12. Red Clay Sediment in the Central Chinese Loess Plateau and Its Implication for the Uplift of the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    SONG Yougui; LI Jijun; FANG Xiaomin; XIA Fei; DONG Hongmei

    2005-01-01

    The widely distributed red clay sediment underlying the Chinese Loess Plateau truly records the Neogene environmental evolution, and its genesis and development are intrinsically related to the uplift processes of the Tibetan Plateau and the evolution of East Asia monsoon system. In this paper, a detailed magnetostratigraphy of a loess-red clay section (107°13′E, 35°02′N) from the central Loess Plateau is reported. The loess-red clay sequence is composed of 175 m Quaternary loess-paleosol sequence and 128 m Neogene red clay sediments. Based on the correlation with the standard geomagnetic polarity time scale, the paleomagnetic results indicate that the age of Chaona red clay sequence extends to 8.1Ma, which is the older red clay deposition in the central Chinese Loess Plateau. The commencement of red clay at ~8.1 Ma may imply that the Ordos planation surface was broken by the movement of the Haiyuan-Liupanshan Faults, which was related to the uplift of the Tibetan Plateau induced by the collision of India Plate and Eurasian Plate. And the western part adjacent to the Tibetan Plateau was uplifted to form the embryo of the Liupan Shan (Mts.) and the eastern part was down-faulted to receive red clay deposition. We link this faulting to an initial uplift of the Tibetan Plateau. The undulating nature of the broken Ordos planation surface may explain the chronological differences and depth discrepancies among various cross-sections of red clay.

  13. Spontaneous collapse of the tibial plateau: radiological staging

    Energy Technology Data Exchange (ETDEWEB)

    Carpintero, P.; Leon, F.; Zafra, M. [University Hospital ' ' Reina Sofia' ' , Orthopaedic Department, Cordoba (Spain); Montero, R.; Carreto, A. [University Hospital ' ' Reina Sofia' ' , Radiology Department, Cordoba (Spain)

    2005-07-01

    This paper proposes a radiological staging system for necrosis of the tibial plateau, similar to those already developed for the hip and the medial femoral condyle. We retrospectively studied the clinical case histories and radiographic findings of 14 patients (15 affected knees) with histologically proven osteonecrosis of the tibial plateau. Stage I was marked by normal radiograph, but increased uptake in bone scan and subchondral areas of abnormal marrow signal intensity in magnetic resonance imaging (MRI), as reported in other osteonecrosis sites. Stage II was characterised by cystic and sclerotic changes, and stage III fracture of the medial rim of the medial tibial plateau and tibial plateau collapse were present. Stage IV was marked by joint narrowing. These changes appeared earlier and were more pronounced when there was genu varum/valgum or involvement of the lateral tibial plateau. The radiological evolution of the disease appears to follow a four-stage course over a period of roughly one year from the onset of symptoms. (orig.)

  14. Rapid Loss of Lakes on the Mongolian Plateau

    Science.gov (United States)

    Tao, S.; Fang, J.; Zhao, X.; Zhao, S.; Shen, H.; Hu, H.; Tang, Z.; Wang, Z.; Guo, Q.

    2015-12-01

    Lakes are widely distributed on the Mongolian Plateau and as critical water sources have sustained Mongolian pastures for hundreds of years. However, the plateau has experienced significant lake shrinkage and grassland degradation during the past several decades. To quantify the changes in all the lakes on the plateau and the associated driving factors, we performed a satellite-based survey using multi-temporal Landsat images from the 1970s to 2000s, combining with ground-based censuses. Our results document a rapid loss of lakes on the plateau in the past decades: the number of lakes with a water surface area >1 km2 decreased from 785 in the late 1980s to 577 in 2010, with a greater rate of decrease (34.0%) in Inner Mongolia of China than in Mongolia (17.6%). This decrease has been particularly pronounced since the late 1990s in Inner Mongolia and the number of lakes >10 km2 has declined by 30.0%. The statistical analyses suggested that in Mongolia precipitation was the dominant driver for the lake changes, while in Inner Mongolia coal mining was most important in its grassland area and irrigation was the leading factor in its cultivated area. The deterioration of lakes is expected to continue in the following decades not only because of changing climate but also increasing exploitation of underground mineral and groundwater resources on the plateau. To protect grasslands and the indigenous nomads, effective action is urgently required to save these valuable lakes from further deterioration.

  15. Venting of a Water/Inhibited Propylene Glycol Mixture in a Vacuum Environment-Characterization and Representative Test Results

    Science.gov (United States)

    Ungar, Eugene K.; Erickson, Lisa R.

    2011-01-01

    A planned use of the Orion space vehicle involves its residence at the International Space Station for six months at a time. One concept of operations involves temporarily venting portions of the idle Orion active thermal control system (ATCS) during the docked phase, preventing freezing. The venting would have to be reasonably complete with few, if any, completely filled pockets of frozen liquid. Even if pockets of frozen liquid did not damage the hardware during the freezing process, they could prevent the system from filling completely prior to its reactivation. The venting of single component systems in a space environment has been performed numerous times and is well understood. Local nucleation occurs at warm, relatively massive parts of the system, which creates vapor and forces the bulk liquid out of the system. The remnants of the liquid will freeze, then evaporate over time through local heating. Because the Orion ATCS working fluid is a 50/50 mixture of water and inhibited propylene glycol, its boiling behavior was expected to differ from that of a pure fluid. It was thought that the relatively high vapor pressure water might evaporate preferentially, leaving behind a mixture enriched with the low vapor pressure propylene glycol, which would be vaporization ]resistant. Owing to this concern, a test was developed to compare the evaporation behavior of pure water, a 50/50 mixture of water and inhibited propylene glycol, and inhibited propylene glycol. The test was performed using room temperature fluids in an instrumented thin walled stainless steel vertical tube. The 1 in x 0.035 in wall tube was instrumented with surface thermocouples and encased in closed cell polyurethane foam. Reticulated polyurethane foam was placed inside the tube to reduce the convection currents. A vacuum system connected to the top of the tube set the pressure boundary condition. Tests were run for the three fluids at back pressures ranging from 1 to 18 torr. During each test

  16. 3D spatially-resolved characterization of chemical environment distributions by inelastic X-ray scattering in confocal setup

    Energy Technology Data Exchange (ETDEWEB)

    Leani, J.J.; Sanchez, H.J.; Perez, R.D. [Universidad Nacional de Cordoba, Cordoba, Cba (Argentina); Perez, C.A. [Laboratoorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil)

    2012-07-01

    Full text: 3D-micro X-ray fluorescence spectroscopy enables non-destructive three-dimensional investigation of elemental distribution in samples in the micrometer regime. In the last few years, accurate quantification procedures have been developed [1,2]. The most important problem in these quantification procedures is the existence of light elements in the sample from which no fluorescence is detected. This dark matrix problem is not yet solved and is now the most serious limitation of this technique [2]. Resonant Raman scattering is an inelastic scattering process that becomes dominant when atoms are irradiated with incident energy lower and close to an absorption edge. Recently, a spectroscopic technique in formation based in this process showed to be useful to distinguish surrounded chemical environments [3,4]. We present first results regarding the possibility of determining the oxidation state of an element, in a three-dimensional regime, by resonant Raman scattering using an energy dispersive system combined with a confocal setup. A depth scanning of a multilayer sample in confocal setup was carried out in the XRF Beamline of the LNLS (Campinas, Brazil) [5]. The sample consisted of different layers of Cu oxides over a Cu substrate. The sample was irradiated with monochromatic photons having energy close but lower than the K absorption edge of Cu. The Raman peaks were analyzed, residuals were determined and a FFT smoothing procedure, taking into account the instrument functions of the detecting system, was applied. The results show an oscillation pattern that depends on the oxidation state of cooper. The result is relevant since allows the discrimination of the oxidation state of the elements present in a sample in a 3D-micrometer regime by means of resonant Raman scattering combined with a confocal setup. This result could be used as a tool to determine the dark matrix present in the sample with the aim of establishing a reliable quantification procedure. 1

  17. Characterization of ultrafine particle number concentration and new particle formation in an urban environment of Taipei, Taiwan

    Science.gov (United States)

    Cheung, H. C.; Chou, C. C.-K.; Huang, W.-R.; Tsai, C.-Y.

    2013-09-01

    An intensive aerosol characterization experiment was performed at the Taipei Aerosol and Radiation Observatory (TARO, 25.02° N, 121.53° E) in the urban area of Taipei, Taiwan, during July 2012. Number concentration and size distribution of aerosol particles were measured continuously, which were accompanied by concurrent measurements of mass concentration of submicron particles, PM1 (d ≤ 1 μm), and photolysis rate of ozone, J(O1D). The averaged number concentrations of total (Ntotal), accumulation mode (Nacu), Aitken mode (NAitken), and nucleation mode (Nnuc) particles were 13.9 × 103 cm-3, 1.2 × 103 cm-3, 6.1 × 103 cm-3, and 6.6 × 103 cm-3, respectively. Accordingly, the ultrafine particles (UFPs, d ≤ 100 nm) accounted for 91% of the total number concentration of particles measured in this study (10 ≤ d ≤ 429 nm), indicating the importance of UFPs to the air quality and radiation budget in Taipei and its surrounding areas. An averaged Nnuc / NOx ratio of 192.4 cm-3 ppbv-1 was derived from nighttime measurements, which was suggested to be the characteristic of vehicle emissions that contributed to the "urban background" of nucleation mode particles throughout a day. On the contrary, it was found that the number concentration of nucleation mode particles was independent of NOx and could be elevated up to 10 times of the "urban background" levels during daytime, suggesting a substantial amount of nucleation mode particles produced from photochemical processes. Averages (± 1σ) of the diameter growth rate (GR) and formation rate of nucleation mode particles, J10, were 11.9 ± 10.6 nm h-1 and 6.9 ± 3.0 cm-3 s-1, respectively. Consistency in the time series of the nucleation mode particle concentration and the proxy of H2SO4 production, UVB · SO2/CS, for new particle formation (NPF) events suggested that photooxidation of SO2 was likely one of the major mechanisms for the formation of new particles in our study area. Moreover, it was revealed that the

  18. Characterization of age-related modifications of upper limb motor control strategies in a new dynamic environment

    Directory of Open Access Journals (Sweden)

    Dario Paolo

    2008-11-01

    Full Text Available Abstract Background In the past, several research groups have shown that when a velocity dependent force field is applied during upper limb movements subjects are able to deal with this external perturbation after some training. This adaptation is achieved by creating a new internal model which is included in the normal unperturbed motor commands to achieve good performance. The efficiency of this motor control mechanism can be compromised by pathological disorders or by muscular-skeletal modifications such as the ones due to the natural aging process. In this respect, the present study aimed at identifying the age-related modifications of upper limb motor control strategies during adaptation and de-adaptation processes in velocity dependent force fields. Methods Eight young and eight elderly healthy subjects were included in the experiment. Subjects were instructed to perform pointing movements in the horizontal plane both in a null field and in a velocity dependent force field. The evolution of smoothness and hand path were used to characterize the performance of the subjects. Furthermore, the ability of modulating the interactive torque has been used as a paradigm to explain the observed discoordinated patterns during the adaptation process. Results The evolution of the kinematics during the experiments highlights important behavioural differences between the two groups during the adaptation and de-adaptation processes. In young subjects the improvement of movement smoothness was in accordance with the expected learning trend related to the consolidation of the internal model. On the contrary, elders did not show a coherent learning process. The kinetic analysis pointed out the presence of different strategies for the compensation of the external perturbation: older people required an increased involvement of the shoulder with a different modulation of joint torque components during the evolution of the experiments. Conclusion The results

  19. Fraturas do planalto tibial Tibial plateau fractures

    Directory of Open Access Journals (Sweden)

    Maurício Kfuri Júnior

    2009-01-01

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

  20. A 2.8 Ma record of environmental evolution and tectonic events inferred from the Cuoe core in the middle of Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    SHEN; Ji; Lü; Houyuan; WANG; Sumin; CHEN; Shiyue; YANG; Xia

    2004-01-01

    Based on a multi-proxy investigation into the deep core of the Cuoe Lake in the middle of Tibetan Plateau, a 2.8 Ma paleoclimatic and paleoenvironmental evolution is reconstructed. The result of magnetic stratum indicates that the lake basin was formed at about 2.8 MaBP, while the multi-proxy analyses of lithology, grain size, magnetic susceptibility and geochemical elements reveal that there have been three major environmental evolution stages and at least two intensive uplifts of the Tibetan Plateau in the lake basin area, i.e. during 2.8-2.5 MaBP, the lake basin came into being as a result of the disaggregation of the planation surface and rapid rising of the Tibetan Plateau. During 2.5-0.8 MaBP, with gradual uplift of the Tibetan Plateau, the environment of this area was more effectively controlled by the climatic cycle of the alternative glacial-interglacial stages. After 0.8 MaBP, the middle part of the Plateau accelerated its uplift and entered cryoshere.

  1. Failure Analysis for the Vehicle Engine Used in Plateau Area%高原地区车辆柴油机故障分析

    Institute of Scientific and Technical Information of China (English)

    刘冰; 王宪成; 何星; 孙志新

    2014-01-01

    针对我国高原地区车辆柴油机使用现状,通过高原环境特点分析,车辆柴油机故障统计以及故障模式、影响及危害性分析,明确高原地区柴油机故障特点和典型故障产生的原因;结合高原环境特点与柴油机使用状况,提出车辆柴油机高原环境条件下合理使用建议与预防故障的改善措施。%In accordance with the application status of vehicle diesel engine used in plateau area of our country, through the analysis of the plateau environment characteristics, vehicle diesel engine failure sta-tistics, and the Failure Mode Effect and Criticality Analysis, the main failure's characteristics and the causes of the typical failure are determined. Combined with the characteristics of plateau environment and the application conditions of diesel engine, reasonable suggestions and preventive or ameliorative meas-ures of failures in the plateau environment are put forward.

  2. Speculation on the timing and nature of Late Pleistocene hunter-gatherer colonization of the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    P. J. Brantingham; MA Haizhou; J. W. Olsen; GAO Xing; D. B. Madsen; D. E. Rhode

    2003-01-01

    Hunter-gatherer populations in greater northeast Asia experienced dramatic range expansions during the early Upper Paleolithic (45-22 ka) and the late Upper Paleolithic (18-10 ka), both of which led to intensive occupations of cold desert environments including the Mongolian Gobi and northwest China. Range contractions under the cold, arid extremes of the Last Glacial Maximum (LGM, 22-18 ka) may have entailed widespread population extirpations. The high elevation Qinghai-Tibetan Plateau is significantly more extreme in both climate and environment than either the Gobi or the Siberian taiga forests, and provides an ideal setting to test fundamental models of human biogeog-raphy in the context of regional population fluctuations. The area is presently occupied primarily by nomadic pastoralists, but it is clear that these complex middle Holocene (<6 ka) economic adaptations were not a necessary prerequisite for successful colonization of the high elevation Plateau. Exploratory field-work in 2000-2001 has established that Upper Paleolithic hunter-gatherers were present on the Qinghai-Tibetan Plateau by at least 12 ka and possibly much earlier. Aspeculative model for the colonization process is developed and preliminary archaeological data in support of the model are presented.

  3. The uplift of Qinghai-Xizang (Tibet) Plateau and the vicariance speciation of glyptosternoid fishes (Siluriformes:Sisoridae)

    Institute of Scientific and Technical Information of China (English)

    何舜平; 曹文宣; 陈宜瑜

    2001-01-01

    Based on the phylogenetic and biogeographical studies of the glyptosternoid fishes in Qinghai-Tibet area, the following hypothesis is proposed: the speciation of this group has a direct relationship with the three uplift intervals of the Qinghai-Tibet Plateau. This process was explained by the theory of vicariance of biogeography. The ancestor of this group was similar to Bagarus and/or Glyptothorax, which still have a wide distribution. At the moment when the Tethys sea closed, the Indian tectonic plate collided with the Eurasian tectonic plate, so the Glyptothorax-like and Bagarus-like ancestors entered Eurasia and gradually became widely distributed. After the Pleistocene, with the enforced colliding, the gradual uplift of the Qinghai-Tibet Plateau brought about the current water environment, and the Glyptosternoids were generated from Glyptothorax-like fish under this environment. The present Glyptosternum, distributed across the Himalayas is the ancestor of Glyptosternoids. In the three uplift intervals of the plateau, the water system of this region was separated gradually and Glyptosternum-like ancestor was isolated in different rivers and evolved into various species. All this resulted in the speciation and formation of the biogeographical pattern of glyptosternoids.

  4. Individual particles of cryoconite deposited on the mountain glaciers of the Tibetan Plateau: Insights into chemical composition and sources

    Science.gov (United States)

    Dong, Zhiwen; Qin, Dahe; Kang, Shichang; Liu, Yajun; Li, Yang; Huang, Jie; Qin, Xiang

    2016-08-01

    Cryoconite deposited on mountain glacier surfaces is significant for understanding regional atmospheric environments, which could influence the albedo and energy balance of the glacier basins, and maintain the glacial microbiology system. Field observations were conducted on the glaciers of western China, including Laohugou Glacier No.12 (LHG), Tanggula Dongkemadi Glacier (TGL), Zhadang Glacier (ZD), and Baishui Glacier No.1 in the Yulong Mountains (YL), as well as Urumqi Glacier No.1 in the Tianshan Mountains (TS) for comparison with locations in the Tibetan Plateau, in addition to laboratory TEM-EDX analysis of the individual cryoconite particles filtered on lacey carbon (LC) and calcium-coated carbon (Ca-C) TEM grids. This work provided information on the morphology and chemical composition, as well as a unique record of the particle's physical state, of cryoconite deposition on the Tibetan Plateau. The result showed that there is a large difference in the cryoconite particle composition between various locations on the Tibetan Plateau. In total, mineral dust particles were dominant (>50%) in the cryoconite at all locations. However, more anthropogenic particles (e.g., black carbon (BC) and fly ash) were found in YL (38%) and ZD (22%) in the Ca-C grids in the southern locations. In TGL, many NaCl and MCS particles (>10%), as well as few BC and biological particles (anthropogenic particles in the southern Tibetan Plateau is likely caused by atmospheric pollutant transport from the south Asia to the Tibetan Plateau. Cryoconite in the northern locations (e.g., TGL, LHG, and TS) with higher dust and salt particle ratio are influenced by large deserts in central Asia. Therefore, the transport and deposition of cryoconite is of great significance for understanding regional atmospheric environment and circulation. Large amounts of biological, NaCl and MCS particles were observed in the cryoconite, implying that in addition to dust and BC, many types of light absorbing

  5. ANALYSIS OF MESOSCALE CONVECTIVE SYSTEMS OVER TIBETAN PLATEAU IN SUMMER

    Institute of Scientific and Technical Information of China (English)

    GUO Zhong-yang; DAI Xiao-yan; WU Jian-ping; LIN Hui

    2006-01-01

    In this paper, Geostationary Meteorological Satellite (GMS) infrared black-body temperature (Tbb) data from June to August 1998 are used to automatically track the activity of Mesoscale Convective System (MCS) over the Tibetan Plateau in China. Consequently, the features of MCS, such as area, intensity, life cycle, activity region and shape, are obtained. High Resolution Limited Area Analysis and Forecasting System (HLAFS) values provided by China National Meteorological Center are used to study the relationships between the MCS trajectories and their environmental physical field values, based on the distribution and trajectories of MCSs over the Tibetan Plateau. Favorable environmental physical field charts of influencing MCS movement out of the Tibetan Plateau in different UTC (Universal Time Coordinate) are developed by using spatial data mining techniques at levels of 400hPa and 500hPa, respectively.

  6. More evidence of the plateau effect: a social perspective.

    Science.gov (United States)

    Pinto-Prades, J L; Lopez-Nicolás, A

    1998-01-01

    The purpose of this study was to test the existence of the plateau effect at the social level. The authors tried to confirm the preliminary conclusion that people may not be willing to trade off any longevity to improve the health state of a large number of people if the health states are mild enough. They tested this assumption using the person-tradeoff technique. They also used a parametric approach and a nonparametric approach to study the relationship between individual and social values. Results show the existence of the plateau effect in the context of resource allocation. Furthermore, with the nonparametric approach, a plateau effect in the middle part of the scale was also observed, suggesting that social preference may not be directly predicted from individual utilities. The authors caution against the possible framing effects that may be present in these kinds of questions.

  7. State of tectonic stress in Shillong Plateau of northeast India

    Science.gov (United States)

    Baruah, Santanu; Baruah, Saurabh; Saikia, Sowrav; Shrivastava, Mahesh N.; Sharma, Antara; Reddy, C. D.; Kayal, J. R.

    2016-10-01

    Tectonic stress regime in the Shillong plateau, northeast region of India, is examined by stress tensor inversion. Some 97 reliable fault plane solutions are used for stress inversion by the Michael and Gauss methods. Although an overall NNW-SSE compressional stress is observed in the area, the stress regime varies from western part to eastern part of the plateau. The eastern part of the plateau is dominated by NNE-SSW compression and the western part by NNW-SSE compression. The NNW-SSE compression in the western part may be due to the tectonic loading induced by the Himalayan orogeny in the north, and the NNE-SSW compression in the eastern part may be attributed to the influence of oblique convergence of the Indian plate beneath the Indo-Burma ranges. Further, Gravitational Potential Energy (GPE) derived stress also indicates a variation from west to east.

  8. Fukushima nuclear accident recorded in Tibetan Plateau snow pits.

    Directory of Open Access Journals (Sweden)

    Ninglian Wang

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

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

    Directory of Open Access Journals (Sweden)

    Minal Desai

    2012-03-01

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

  10. The impacts of the summer plateau monsoon over the Tibetan Plateau on the rainfall in the Tarim Basin, China

    Science.gov (United States)

    Zhao, Yong; Huang, Anning; Zhou, Yang; Yang, Qing

    2016-10-01

    The impacts of the summer plateau monsoon (PM) over the Tibetan Plateau on summer rainfall over the Tarim Basin in northwest China are investigated, based on the observed rainfall data at 34 stations and the NCEP/NCAR reanalysis data during 1961 to 2007. Results showed that the PM is well correlated to the summer rainfall over the Tarim Basin. Process analysis shows that strong PM corresponds to an anomalous cyclone over the Tibetan Plateau in the middle troposphere and an anomalous anticyclone in the upper troposphere over northwest part of Tibetan Plateau. They result in cold air moving from high latitudes into Central Asia over the western part of Tibetan Plateau. The concurrences of the cooling in the middle-upper troposphere over Central Asia leads to an anomalous cyclone over Central Asia at 500 hPa and the anomalous descending motions prevailing over the cooling region. Associated with this anomaly, there are enhanced southerly winds and corresponding ascending motion over the Tarim Basin located in the east of the cooling region. These processes lead to more summer rainfall over the Tarim Basin.

  11. In vitro comparison of tibial plateau leveling osteotomy with and without use of a tibial plateau leveling jig.

    Science.gov (United States)

    Schmerbach, Kay Ingo; Boeltzig, Christian Konrad Matthias; Reif, Ullrich; Wieser, Jan Carsten; Keller, Thomas; Grevel, Vera

    2007-02-01

    To evaluate the influence of a tibial plateau leveling jig on osteotomy orientation, fragment reduction, and postoperative tibial plateau angle (TPA) during tibial plateau leveling osteotomy (TPLO). In vitro experimental study. Large-breed canine cadavers (n=20). TPLO was performed on 40 hindlimbs using 4 methods. Group 1: Jig; dogs in dorsal recumbency with the osteotomy parallel to the distal jig pin. Groups 2-4: No jig; dogs in lateral recumbency with the osteotomy in a vertical orientation (group 2: tibia parallel to the table top; group 3: controlled superimposition of the femoral condyles; group 4: internal rotation of the tibia). Postoperative TPA, fragment reduction, and osteotomy orientation relative to the tibial plateau were compared. Positive or negative values denoted deviation from parallel relative to the tibial plateau. Postoperative TPA, fragment reduction, and proximodistal osteotomy orientation were not significantly different between groups. Craniocaudal osteotomy orientation was significantly different (Ptable surface. TPLO without use of a jig reduces surgical trauma, is less time consuming, and reduces cost.

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

    Directory of Open Access Journals (Sweden)

    Minal Desai

    2012-03-01

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

  13. Prevalence and characterization of Staphylococcus aureus and Staphylococcus pseudintermedius isolated from companion animals and environment in the veterinary teaching hospital in Zambia, Africa.

    Science.gov (United States)

    Youn, Jung-Ho; Park, Yong Ho; Hang'ombe, Bernard; Sugimoto, Chihiro

    2014-03-01

    The Republic of Zambia consists of only one veterinary teaching school at the University of Zambia (UNZA) where students and veterinarians are exposed to many bacterial pathogens including Staphylococcus aureus (SA) and Staphylococcus pseudintermedius (SP). The aim of this study was the characterization and antimicrobial susceptibility profile of eleven SA and 48 SP isolates from the veterinary hospitals' in- and outpatients and the environment. No isolate was resistant to cefoxitin by disk diffusion test and the corresponding resistance gene mecA was not found. In contrast, the resistance rates of SA to penicillin (63.6%) and trimethoprim-sulfamethoxazole (36.4%) and SP to penicillin (52.1%) and tetracycline (25.0%) were the highest. A variety of sequence types (STs) without a predominant type including numerous novel types were determined, especially for SP (39.6%). The spa typing provided a clonal assignment for all SAs (100%) and 24 SPs (50%) with three and two novel types, respectively. This study has provided an overview of SA and SP in the veterinary teaching hospital at UNZA. However, for a better understanding of these species regarding pathogenesis and transmission, further studies on the prevalence and characterization of SA and SP from veterinary staff, pet owners, and farm animals in Zambia is needed.

  14. Impulse response characterization of the propagation and scattering environment in through-wall applications using an S-band noise radar

    Science.gov (United States)

    Smith, Sonny; Narayanan, Ram M.

    2012-06-01

    An ultrawideband (UWB) random noise radar operating at S-Band has been developed for through-wall detection, ranging, tracking, and imaging of targets. The system transmits a bandlimited UWB noise signal and accomplishes detection by cross-correlating the reflected signal with a time-delayed replica of the transmit signal. Noise radars have been found eminently suitable for most though-wall radar applications. Yet, in such scenarios, the antennas and the barrier (i.e. the wall) cause distortions in the return signal due to their frequency-dependent radiation and loss characteristics, respectively. In this paper, we explore the feasibility of characterizing the impulse response of various barriers and obstructions via measurements with the S-Band noise radar. As is well known, the entire operation of a linear system (e.g., antenna or barrier) can be captured in its impulse response h(t), i.e. the output of the system when excited by an impulse function at its input, δ(t). Thus, impulse response testing, generally, provides a complete diagnosis of the system over its entire mode of operation. This paper will present results on our impulse response characterization of the propagation and scattering environment through a barrier by the atypical method of cross correlation of noise signals. In addition, we will introduce a simple electromagnetic forward model for wall propagation and accompanying simulations.

  15. Atmospheric moisture supersaturation in the near-surface atmosphere at Dome C, Antarctic Plateau

    Science.gov (United States)

    Genthon, Christophe; Piard, Luc; Vignon, Etienne; Madeleine, Jean-Baptiste; Casado, Mathieu; Gallée, Hubert

    2017-01-01

    Supersaturation often occurs at the top of the troposphere where cirrus clouds form, but is comparatively unusual near the surface where the air is generally warmer and laden with liquid and/or ice condensation nuclei. One exception is the surface of the high Antarctic Plateau. One year of atmospheric moisture measurement at the surface of Dome C on the East Antarctic Plateau is presented. The measurements are obtained using commercial hygrometry sensors modified to allow air sampling without affecting the moisture content, even in the case of supersaturation. Supersaturation is found to be very frequent. Common unadapted hygrometry sensors generally fail to report supersaturation, and most reports of atmospheric moisture on the Antarctic Plateau are thus likely biased low. The measurements are compared with results from two models implementing cold microphysics parameterizations: the European Center for Medium-range Weather Forecasts through its operational analyses, and the Model Atmosphérique Régional. As in the observations, supersaturation is frequent in the models but the statistical distribution differs both between models and observations and between the two models, leaving much room for model improvement. This is unlikely to strongly affect estimations of surface sublimation because supersaturation is more frequent as temperature is lower, and moisture quantities and thus water fluxes are small anyway. Ignoring supersaturation may be a more serious issue when considering water isotopes, a tracer of phase change and temperature, largely used to reconstruct past climates and environments from ice cores. Because observations are easier in the surface atmosphere, longer and more continuous in situ observation series of atmospheric supersaturation can be obtained than higher in the atmosphere to test parameterizations of cold microphysics, such as those used in the formation of high-altitude cirrus clouds in meteorological and climate models.

  16. Records of anthropogenic antimony in the glacial snow from the southeastern Tibetan Plateau

    Science.gov (United States)

    Zhang, Yulan; Kang, Shichang; Chen, Pengfei; Li, Xiaofei; Liu, Yajun; Gao, Tanguang; Guo, Junming; Sillanpää, Mika

    2016-12-01

    Antimony (Sb) is a ubiquitous element in the environment that is potentially toxic at very low concentrations. In this study, surface snow/ice and snowpit samples were collected from four glaciers in the southeastern Tibetan Plateau in June 2015. The concentrations of Sb and other elements were measured in these samples. The results showed that the average concentration of Sb was approximately 2.58 pg g-1 with a range of 1.64-9.20 pg g-1. The average Sb concentration in the study area was comparable to that recorded in a Mt. Everest ice core and higher than that in Arctic and Antarctic snow/ice but much lower than that in Tien Shan and Alps ice cores. Sb presented different variations with other toxic elements (Pb and Cr) and a crustal element (Al) in the three snowpits, which indicated the impact of a different source or post-deposition processes. The enrichment factor of Sb was larger than 10, suggesting that anthropogenic sources provided important contributions to Sb deposition in the glaciers. The Sb in the glacial snow was mainly loaded in the fourth component in principal component analysis, exhibiting discrepancies with crustal elements (Fe and Ca) and other toxic metals (Pb). Backward trajectories revealed that the air mass arriving at the southeastern Tibetan Plateau mostly originated from the Bay of Bengal and the South Asia in June. Thus, pollutants from the South Asia could play an important role in Sb deposition in the studied region. The released Sb from glacier meltwater in the Tibetan Plateau and surrounding areas might pose a risk to the livelihoods and well-being of those in downstream regions.

  17. The occurrence of a grassy vegetation over the Chinese Loess Plateau since the last interglacier: the molecular fossil record

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A series of allochthonous and autochthonous molecular fossils were identified from the Holocene paleosol (S0), Malan Loess (L1) and the top Lishi Loess (S1) in Jiuzhoutai loess profile in Lanzhou through the GC/MS analysis. The allochthonous molecules were transported into the Plateau by the loess grains whilst the autochthonous molecules were related to the input of the local paleo-vegetation and could be used to reconstruct the paleo-vegetation. The distribution of the autochthonous n-alkanes was discriminated from the overlapping allochthonous homologues characterized by the CPI value of unity. The dominance of autochthonous C31 n-alkane implicates the occurrence of a grassy vegetation over the Loess Plateau since the last interglacier. The warmest period of the Holocene, though dominated by grass, was additionally characterized by the relatively increased abundance of C27 n-alkane indicative of woody plants. The desert plants might occur during the last glacier. The molecular fossil record is not contradictory with the recent phytolith data, denying the occurrence of a forest over the Plateau since the last interglacier. These data from the loess molecular stratigraphy indicate the importance of the discrimination of the autochthonous molecules from the allochthonous compounds.

  18. DREAMS: a payload on-board the ExoMars EDM Schiaparelli for the characterization of Martian environment during the statistical dust storm season

    Science.gov (United States)

    Molfese, Cesare; Esposito, Francesca; Debei, Stefano; Bettanini, Carlo; Arruego Rodríguez, Ignacio; Colombatti, Giacomo; Harri, Ari-Matty.; Montmessin, Franck; Wilson, Colin; Aboudan, Alessio; Mugnuolo, Raffaele; Pirrotta, Simone; Marchetti, Ernesto; Witasse, Olivier

    2015-04-01

    F. Esposito1, S. Debei2, C. Bettanini2, C. Molfese1, I. Arruego Rodríguez3, G. Colombatti2, A-M. Harri4, F. Montmessin5, C. Wilson6, A. Aboudan2, S. Abbaki5, V. Apestigue3, G. Bellucci7, J-J. Berthelier5, J. R. Brucato8, S. B. Calcutt6, F. Cortecchia1, F. Cucciarrè2, G. Di Achille1, F. Ferri2, F. Forget9, E. Friso2, M. Genzer4, P. Gilbert5, H. Haukka4, J. J. Jiménez3, S. Jiménez10, J-L. Josset11, O. Karatekin12, G. Landis13, R. Lorenz14, J. Martinez3, L. Marty1, V. Mennella1, D. Möhlmann15, D. Moirin5, R. Molinaro1, E. Palomba7, M. Patel16, J-P. Pommereau5, C.I. Popa1, S. Rafkin17, P. Rannou18, N.O. Renno19, P. Schipani1, W. Schmidt4, E. Segato2, S. Silvestro1, F. Simoes20, A. Spiga9, F. Valero21, L. Vázquez21, F. Vivat5, O. Witasse22, R. Mugnuolo23, S. Pirrotta23, E.Marchetti23 1INAF - Osservatorio Astronomico di Capodimonte, Napoli, Italy, 2CISAS - Università degli Studi di Padova, Padova, Italy, 3INTA, Spain, 4Finnish Meteorological Institute (FMI),Helsinki, Finland, 5LATMOS - CNRS/UVSQ/IPSL, France, 6Oxford University, Oxford, United Kingdom, 7INAF - Istituto di Fisica dello Spazio Interplanetario (IFSI), 8INAF-Osservatorio Astrofisico di Arcetri, 9CNRS, LMD, France, 10Universidad Politécnica de Madrid, Spain, 11Space Exploration Institute, Switzerland, 12Royal Observatory of Belgium,Belgium, 13NASA, GRC, USA, 14JHU Applied Physics Lab (JHU-APL), USA, 15DLR PF Leitungsbereich, Berlin, Germany, 16Open University, UK, 17SwRL, Switzerland, 18GSMA, France, 19University of Michigan, USA, 20NASA, GSFC, USA, 21Universidad Complutense de Madrid (UCM), Spain, 22ESA-ESTEC, Noordwijk, The Netherlands, 23Italian Space Agency, Italy DREAMS (Dust characterization, Risk assessment and Environment Analyzer on the Martian Surface) package is an integrated multi-sensor scientific payload dedicated to characterizing the landing site environment in dusty conditions. It will measure pressure, wind speed and direction, relative humidity, temperature, the solar irradiance

  19. Revisiting Asian monsoon formation and change associated with Tibetan Plateau forcing: II. Change

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yimin; Wu, Guoxiong; Duan, Anmin; Bao, Qing [Chinese Academy of Sciences, State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Beijing (China); Hong, Jieli; Zhou, Linjiong [Chinese Academy of Sciences, State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Beijing (China); Graduate University of Chinese Academy of Sciences, Beijing (China); Dong, Buwen [University of Reading, Department of Meteorology, National Centre for Atmospheric Science, Reading (United Kingdom)

    2012-09-15

    Data analysis based on station observations reveals that many meteorological variables averaged over the Tibetan Plateau (TP) are closely correlated, and their trends during the past decades are well correlated with the rainfall trend of the Asian summer monsoon. However, such correlation does not necessarily imply causality. Further diagnosis confirms the existence of a weakening trend in TP thermal forcing, characterized by weakened surface sensible heat flux in spring and summer during the past decades. This weakening trend is associated with decreasing summer precipitation over northern South Asia and North China and increasing precipitation over northwestern China, South China, and Korea. An atmospheric general circulation model, the HadAM3, is employed to elucidate the causality between the weakening TP forcing and the change in the Asian summer monsoon rainfall. Results demonstrate that a weakening in surface sensible heating over the TP results in reduced summer precipitation in the plateau region and a reduction in the associated latent heat release in summer. These changes in turn result in the weakening of the near-surface cyclonic circulation surrounding the plateau and the subtropical anticyclone over the subtropical western North Pacific, similar to the results obtained from the idealized TP experiment in Part I of this study. The southerly that normally dominates East Asia, ranging from the South China Sea to North China, weakens, resulting in a weaker equilibrated Sverdrup balance between positive vorticity generation and latent heat release. Consequently, the convergence of water vapor transport is confined to South China, forming a unique anomaly pattern in monsoon rainfall, the so-called ''south wet and north dry.'' Because the weakening trend in TP thermal forcing is associated with global warming, the present results provide an effective means for assessing projections of regional climate over Asia in the context of global

  20. Paleoenvironmental responses to Late Cretaceous Oceanic Anoxic Event 2 on the Kerguelen Plateau

    Science.gov (United States)

    Dickson, A.; Saker-Clark, M.; Jenkyns, H. C.; Erba, E.; Bottini, C.; Murphy, M. J.; Gorbanenko, O.; Idiz, E.; van den Boorn, S.

    2014-12-01

    Oceanic Anoxic Event 2 (OAE-2, ~94 Ma: late Cretaceous) was characterized by a perturbation in seawater chemistry, an expansion of marine anoxia and euxinia, an increase in marine organic-carbon burial, a decrease in atmospheric pCO2 during an interval of high global temperatures, an extinction event among marine organisms, and changes in weathering intensity. However, many of the most detailed studies of OAE-2 are from the northern hemisphere, and consequently how global environmental changes were expressed at the local and regional scale in the southern hemisphere is poorly understood. A detailed geochemical, petrographic and micropalaeontological dataset from Ocean Drilling Program Site 1138 on the Kerguelen Plateau, southern Indian Ocean (53.5oS paleolatitude), identifies OAE-2 from a 3‰ positive carbon-isotope excursion (CIE) and from high-resolution nannofossil biostratigraphy. An enrichment of organic carbon (to ~15%) corresponds with a shift towards locally sub-oxic/anoxic conditions, as recorded by trace-metal enrichments and molybdenum-isotope compositions. The redox changes coincide stratigraphically with an abrupt decline in the delivery of highly weathered detrital material and terrestrial organic matter to Site 1138. A rapid relative sea-level rise occurring around the onset of OAE-2 could have reduced the input of highly weathered detrital sediments, while moving the local seafloor deeper into an oxygen minimum zone impinging on the margins of the Kerguelen Plateau. Alternatively, or additionally, intensified mid-latitude hydrological cycling in the early stages of OAE-2 could have rapidly destabilized terrestrial sediments from sub-aerial landmasses on the Kerguelen Plateau. In either case, the new datasets highlight the abrupt nature of the palaeoenvironmental response to OAE-2 in the mid-latitude southern hemisphere.

  1. 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

    , made up for the deficiency of using single LTC. The LTDC operator discarded the structure information of local texture and retained the difference information of local texture, with low compute complexity. Aimed at the uncertainty and randomness of plateau pika motion, considering the prior knowledge that the position displacement between two adjacent frames was smaller in smooth movement and the position displacement between two adjacent frames was larger in abrupt motion, we extracted motion information between the adjacent frames using the frame difference method at first, then judged the movement mode of plateau pika by motion information, taking appropriate sampling tracking strategy to track plateau pika. If the mode was judged to be a smooth motion mode, we employed the Markov Chain Monte Carlo sampling tracking method based on the motion smoothness assumption. Else we adopted Wang-Landau Monte Carlo sampling tracking method used for abrupt motion tracking. Considering the fact of that object tracking method of motion-induction algorithm based on HSV color histogram usually had the deformation of inaccurate tracking or loss of target in the scenario where the color was similar between the background and the object, the LTDC operator was combined with RGB color information to characterize the object model, and the object model was embedded into the motion induction tracking framework for the plateau pika tracking. The test video collected the plateau pika activity behavior in the winter of 2014 in natural habitat environment, located in Qinghai-Tibet Plateau, eastern longitude 101°35′36″ -102°58′15″, northern latitude 33°58′21″ -34°48′48″. The video was totally 254 frames, with its size 320 pixels×240 pixels, and the fame rate 25 frames per second. The video feature was that the color was very similar between the plateau pika and background. Simultaneously, the plateau pika motion, being abrupt and occurring occasionally, was very stochastic

  2. Petrogenesis and tectonic implications of Upper Triassic appinite dykes in the East Kunlun orogenic belt, northern Tibetan Plateau

    Science.gov (United States)

    Liu, Bin; Ma, Chang-Qian; Huang, Jian; Wang, Lian-Xun; Zhao, Shao-Qing; Yan, Rong; Sun, Yang; Xiong, Fu-Hao

    2017-07-01

    This paper presents geochronological, mineralogical, geochemical, and Sr-Nd isotopic data for recently identified Upper Triassic appinite dyke swarms in the East Kunlun orogenic belt (EKOB), northern Tibetan Plateau. Zircon U-Pb isotopic analyses using SHRIMP and LA-ICP-MS techniques yield 206Pb/238U ages of 226.1 ± 1.9 Ma and 226.4 ± 3.5 Ma, which can be interpreted as the crystallization ages of the appinite dykes. All the samples are characterized by high Al2O3 contents, enrichments in light rare earth elements (LREEs) and large ion lithophile elements (LILEs) and strong depletions in Nb, Ta, Ti and P. These characteristics are comparable to those of subduction-related calc-alkaline high-Al basalts. Delayed plagioclase nucleation caused by relatively high-pressure conditions and high H2O contents is the most likely interpretation of the high Al contents. The geochemical and isotopic variations suggest that the appinite dykes were derived from partial melting of a mixed mantle source consisting of enriched lithospheric mantle and MORB-type asthenospheric mantle and had experienced some degree of crustal contamination during migration through continental crust. The appinite dykes are associated with previously documented, contemporaneous high-Ba-Sr and/or high-Sr/Y granites (225-223 Ma) derived from thickened mafic lower crust. These rocks provide important constraints on the compositional variation