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1

Assessment of Potentially Dangerous Glacial Lakes in Chinese Himalayas  

Science.gov (United States)

Glacial lake outburst floods (GLOFs) are catastrophic discharges of water resulting primarily from melting glaciers. In the face of global warming, most Himalayan glaciers have been retreating at a rate that ranges from a few meters to several tens of meters per year, resulting in an increase in the number and size and size of glacial lakes and a concomitant increase in the threat of GLOFs. In the past 50 years, 16 GLOF events which were reported in Tibet had caused the loss of human lives as well as severe damage to local infrastructure. Based on the combination of temperature and precipitation of these 14 failed moraine-dammed lakes, the climatic background could be classified into 4 types, that is, warm-wet, warm-arid, cold-wet and near common weather condition. Under different climatic background types, the outburst mechanisms can be further divided into 5 types and 21 modes based on the analysis of 31 failed moraine-dammed lakes documented all over the world. As to a potentially dangerous moraine-dammed lake, all possible breach modes under each climatic background are firstly described and its qualitative possibilities are given by experts, then the decision-making trees are formed and the breach probability of the potentially dangerous moraine-dammed lake can be calculate. The breaching probabilities of the 143 potentially dangerous moraine-dammed lakes were calculated one by one using the decision-making trees model in Chinese Himalayas. The calculating results show that there are 44 lakes with very high breaching probability, 47 lakes with high breaching probability, 24 lakes with median breaching probability, 24 lakes with low breaching probability, 4 lakes with very low breaching probability. The 91 lakes with very high and high breaching probability rate should be requested in the next steps of detailed assessment and should be took into account in local infrastructure construction, such as road, hydropower station and residential plan, etc. Key words: GLOF, Chinese Himalayas, Dangerous Glacial Lakes

Xiaojun, Yao; Shiyin, Liu; Xin, Wang

2010-05-01

2

Report examines potential impacts of glacial change in Himalayas  

Science.gov (United States)

Glaciers appear to be retreating at accelerating rates in the eastern and central regions of the Himalayas, although in the western Himalayas they appear to be more stable and may be advancing, according to a 12 September report by a committee of the U.S. National Research Council that examines climate change, water resources, and water security issues in the region. The report highlights several themes in considering the link between people and the environment within the context of water security in the Hindu Kush-Himalayan (HKH) region. Among the themes are that there is significant variability in climate, hydrology, and glacier behavior within HKH that makes it difficult to generalize observations and findings across the region and that there is also variability in demographics and water use patterns. Other themes in the report are that uncertainties exist in the region's physical and social systems, including the effect of increased urbanization and changes in standards of living; improved monitoring of physical and social systems is needed to reduce and respond to uncertainty; and improved water management and hazard mitigation systems are the most compelling needs. For more information, see http://www.nap.edu/catalog.php?record_id=13449.

Showstack, Randy

2012-09-01

3

Outbursts of landslide dammed lakes - mapping their potential across the Himalaya  

Science.gov (United States)

Lake formation as a result of river damming by landslides is frequently observed in the Himalayas. Historic records are riddled with sudden failures of debris dams that culminated in catastrophic outburst floods and debris flows with far-reaching devastating consequences for downstream communities and infrastructure. In addition, it has been argued that the formation of large orogens is tightly coupled with the damming of these lakes as they trap sediments and abate river incision. The severity of outburst floods of landslide dammed lakes is directly related to the impounded water volume and downstream channel morphology both of which are controlled by topography. Prime insights into the spatial patterns of hazards generated by landslide dammed lakes can thus be inferred from digital elevation models (DEMs) that are available at sufficient detail at even the remotest localities. Here we quantify from topographic constraints the physically possible size range of catastrophic outburst events at the mountain-belt scale. By manipulating digital topographic, climatic, and river discharge data we estimate to first order the potential peak discharge arising from failure of hypothetical dams occurring anywhere throughout the Himalayan drainage network. Thus modelled peak discharges encompass four to six orders of magnitude, with the most extreme events surpassing the largest documented monsoon floods by a factor of >100. For a range of pre-defined breach rates, the heavy-tailed size distribution of peak discharge stretches with increasing dam height. Our simulation predicts the highest peak discharge for dam breaks outside of the Higher Himalaya, i.e. along the margins of the Tibetan Plateau, and the large orogen-parallel rivers of the Sub-Himalaya. Many of the bedrock rivers slicing through the Higher Himalaya are simply too steep to allow for trapping large quantities of water behind natural dams. This regional consistent pattern underscores the notion that high transient stream power associated with episodic natural dam breaks may play a dominant role in enhancing fluvial bedrock incision in the Higher Himalayas. From a hazard management perspective our data provide a promising and proactive tool for rapidly assessing the likely impacts of outburst events anywhere in the Himalayas.

Schwanghart, Wolfgang; Blöthe, Jan; Andermann, Christoff; Korup, Oliver

2013-04-01

4

Selection of suitable lichen bioindicator species for monitoring climatic variability in the Himalaya.  

Science.gov (United States)

Interspecific comparison in metals and PAHs profile in three lichen species, Flavoparmelia caperata, Phaeophyscia hispidula and Pyxine sorediata, were studied in different altitudinal gradients of the Western Himalayas. The species collected from 14 sites, enroute from Dehradun to Morinda (243 Km) including the trekking route 42 Km from Taluka to Morinda having an altitudinal gradient between 850-3,750 m, were analysed for their metals and PAHs. The species showed similar metal as well as PAHs profile under similar altitudinal gradients in the sequence of F. caperata > P. hispidula > P. sorediata. The difference in pollutant concentrations within each lichen species may be related to intrinsic attributes of the species, such as thallus morphology and the presence of lichen substances which are responsible for the sensitivity and accumulation potential of a particular species. Novelty of the present study lies on the fact that all the species show a similar efficiency of reflecting the environmental condition of the area, albeit the coefficient values of individual species for individual pollutant obtained by three-factor ANOVA revealed that the bioaccumulation affinity of F. caperata is significantly higher than P. hispidula and P. sorediata. For individual metals, F. caperata has a higher affinity for Al, Cr, Fe, Pb and Zn while P. hispidula has a significant positive affinity for Fe and Pb. PCA analysis of sites with respect to pollutant revealed the segregation of sites based on source and distance. Combining the bioaccumulation potential parameters along with geostatistical (GIS) techniques establishes that F. caperata species is a better accumulator of metals and PAHs in comparison to P. hispidula and P. sorediata in the temperate regions of the Himalaya. PMID:24888615

Bajpai, Rajesh; Shukla, Vertika; Upreti, D K; Semwal, Manoj

2014-10-01

5

Potential effects of ongoing and proposed hydropower development on terrestrial biological diversity in the Indian Himalaya.  

Science.gov (United States)

Indian Himalayan basins are earmarked for widespread dam building, but aggregate effects of these dams on terrestrial ecosystems are unknown. We mapped distribution of 292 dams (under construction and proposed) and projected effects of these dams on terrestrial ecosystems under different scenarios of land-cover loss. We analyzed land-cover data of the Himalayan valleys, where dams are located. We estimated dam density on fifth- through seventh-order rivers and compared these estimates with current global figures. We used a species-area relation model (SAR) to predict short- and long-term species extinctions driven by deforestation. We used scatter plots and correlation studies to analyze distribution patterns of species and dams and to reveal potential overlap between species-rich areas and dam sites. We investigated effects of disturbance on community structure of undisturbed forests. Nearly 90% of Indian Himalayan valleys would be affected by dam building and 27% of these dams would affect dense forests. Our model projected that 54,117 ha of forests would be submerged and 114,361 ha would be damaged by dam-related activities. A dam density of 0.3247/1000 km(2) would be nearly 62 times greater than current average global figures; the average of 1 dam for every 32 km of river channel would be 1.5 times higher than figures reported for U.S. rivers. Our results show that most dams would be located in species-rich areas of the Himalaya. The SAR model projected that by 2025, deforestation due to dam building would likely result in extinction of 22 angiosperm and 7 vertebrate taxa. Disturbance due to dam building would likely reduce tree species richness by 35%, tree density by 42%, and tree basal cover by 30% in dense forests. These results, combined with relatively weak national environmental impact assessment and implementation, point toward significant loss of species if all proposed dams in the Indian Himalaya are constructed. PMID:22985327

Pandit, Maharaj K; Grumbine, R Edward

2012-12-01

6

Altitude and Tissue Type Influence Antioxidant Potential of Pellia endiviifolia from Darjeeling Himalaya  

Directory of Open Access Journals (Sweden)

Full Text Available Herbal remedy is considered as one of the popular forms of alternative and complementary medicines. Plants are considered to possess a number of chemical constituents with diverse pharmacological efficacies. Bryophytes, a small group of plants, are known to contain unique secondary metabolites having pharmacological and potential therapeutic value. The primary focus of the study is to depict the role of altitude and tissue types on antioxidant capacity of the liverwort Pellia endiviifolia (Dicks. Dumort. (Pelliaceae. In the present investigation, an attempt has been made to explore the antioxidative potential of vegetative and reproductive tissues of P. endiviifolia collected from five different altitudes of Darjeeling Himalaya, West Bengal, India. Total phenolics and flavonoids contents of the liverwort samples were also determined. Methanol extract of the thalloid liverwort was investigated for antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, total phenolic and flavonoid estimation. Maximum radical scavenging activity was found to be 89.336%±4.3. Maximum total phenolics content in 1 mg of the extract was 58±0.175 ?g of Gallic Acid Equivalent (GAE per mg dry weight. Maximum flavonoids content in 1mg of the extract was 80.3±331 ?g of Quercetin Equivalent (QE per mg dry weight. The results indicate, for the first time, the antioxidative potential and possible use of the liverwort as a natural antioxidant. It also shows a variation of antioxidant capacity of the liverwort depending on their tissue type and their altitude of occurrence.

Abhijit Dey

2013-01-01

7

Seedling growth and survival of selected wild edible fruit species of the Sikkim Himalaya, India  

Science.gov (United States)

In the Sikkim Himalaya, an enormous variety of wild growing plants are exploited at large scale for collection of their edible parts, of which six most prominently utilized fruit species (viz., Baccaurea sapida, Diploknema butyracea, Elaeagnus latifolia, Eriolobus indica, Machilus edulis and Spondias axillaris) were investigated. The growth of nursery raised seedlings was measured at 3 month intervals until two years old in terms of absolute growth rate (AGR), relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), leaf weight ratio (LWR), stem weight ratio (SWR), root weight ratio (RWR) and root-shoot ratio (RSR). Spondias axillaris and Machilus edulis had the maximum AGR, RGR, LAR and SWR among all species. LWR was highest for B. sapida. RGR, LAR and LWR declined with the age of seedlings. RGR was negatively correlated with NAR, SWR, RWR and RSR, though it showed a positive relationship with LAR. For all species, seedlings attained significant sizes after one year of age, and showed reasonable survival after transplantation into the farmers' fields. It is expected that information on the growth behaviour of these species would be useful while they are adopted into agroforestry systems. It is suggested that these species should be multiplied at large scale and distributed to the local inhabitants to reduce pressure on them in natural stands as well as provide economic benefit to the subsistence farmers.

Sundriyal, Manju; Sundriyal, R. C.

2005-07-01

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Hydrology of Himalayas Mountains through gauging of flood and Glaciers Melt historic data hydrographs over selected watersheds under changing climate, Pakistan  

Science.gov (United States)

Mountainous areas of higher altitudes in the northern Pakistan have numerous rivers of great surface runoff during the rainy months and glaciers melt seasons that play a significant role in water resources and hydro-power production. Many of these rivers are unexploited for their water resource potential. If the potential of these rivers are explored, hydro-power production and water supplies in these areas may be improved. The Indus is the mighty river in the Asian countries originating from mountainous area of the Himalayas of Baltistan, Pakistan in which most of the smaller streams and four main rivers drain. Under the larger interest of the economic development of the country, hydrology of these mountainous in northern Pakistan is studied in the perspective of climate change, which includes eight watersheds namely Gilgit, Hunza, Shigar, Shyok, Astore, Jhelum, Swat and Chitral. Available historic data from1960-2005 have been precisely utilized to study the hydrological changes with respect to variability in precipitation, temperature and mean monthly flows, trend of snow melt runoff, daily hydrographs of selected periods (1990 to 1999), water yield and runoff relationship, and flow duration curves. Precipitation from ten meteorological stations in mountainous area of northern Pakistan has not shown uniform distribution of rains but variability in the winter and summer rains is noticed. Review of mean monthly temperature of ten stations suggested that the Upper Indus Basin can be categorized into three hydrological regimes i.e., high altitude catchments with large glacierized parts, middle altitude catchments south of Karakoram, and foothill catchments. A 3-D finite element model (Feflow) has also been used for regional groundwater flow modeling of the Upper Chaj Doab in Indus Basin, Pakistan.

Ahmad, Z.

2013-12-01

9

Evolution of supra-glacial ponds on a debris-covered Chamlang South Glacier, Nepal Himalaya to a potentially dangerous glacial lake  

Science.gov (United States)

A number of moraine dammed glacial lakes have been developed in the Himalayan region since 1950s as a result of melting and retreat of debris-covered glaciers. Such glacial lakes sometimes produce devastating glacier lake outburst floods (GLOFs) which are often several times bigger than normal climatic floods. In Nepal Himalaya, about a score glacial lakes have been identified as ';potentially dangerous' largely relying on remote sensing image analyses. Chamlang South Glacier Lake in the Eastern Nepal Himalaya, which evolved from few tiny supra-glacial ponds in 1960s on debris-covered Chamlang South Glacier into a large glacial lake is one among them. Moreover, the lake has been repeatedly cited as a potentially dangerous lake for a glacial lake outburst flood (GLOF) and also regarded as one of the most highly prioritized critical lakes in Nepal Himalaya. However, detailed investigation of the lake either by field survey or remote sensing has not been carried out on Chamlang South Glacier/Glacier Lake hitherto. We carried out surface area and bathymetric mappings of the lake, detailed topographic mappings of moraine dam complex and surrounding of the glacial lake, and field assessment to examine the development of Chamlang South Glacier Lake, and to assess its prospect of GLOF and potential volume of water to be released from the lake in the event of dam breach. High-resolution Corona KH-4A and Advanced Land Observing Satellite (ALOS) PRISM stereo-data taken in 1964 and 2006 respectively were processed to generate digital terrain models (DTMs). Surface area of supra-glacial ponds in 1964 was 0.040 km2 which grew to 0.636 km2 by 1992 and reached 0.864 km2 by 2000 and virtually stopped expanding thereafter. Produced bathymetric map revealed the lake to be 87 m deep (maximum) and volume of water contained in the lake was calculated to be ~35.6 × 106 m3. Extensive surface lowering as high as 156.9 m, and average surface lowering by 2.2 m/year is found. All topographic and geomorphic conditions (e.g., position and condition of hanging glacier, precarious mountain slope surrounding the lake conducive to ice/glacier and rock falls, steep, high and fragile terminal moraine topography, high relative height between the lake bottom and stable ground at the foothill of terminal moraines, low-raised dam in dead-ice area adjacent to lake), and existence of seepage in end moraine complex favor the lake to be potentially dangerous. However, the lake has a wide dead-ice area between the lake and end moraine dam that most likely neutralize displacement waves produced in the event of snow/ice avalanche or rock fall into the lake. Nevertheless, there is likely to drain almost all water contained in the lake (~35.6 × 106 m3) if dam breach of Chamlang South Glacier Lake occurs. In a nutshell, prospect of GLOF from the lake is moderate; however, if moraine dam breaks, potential volume of water to be drained would apparently be high.

Lamsal, D.; Sawagaki, T.; Watanabe, T.; Sakai, A.

2013-12-01

10

Feeding of oak (Quercus leucotrichophora) leaves and evaluation for its potential inclusion in the feeding of native heifers of Kumaon Himalaya.  

Science.gov (United States)

After an initial survey on feeds and feeding practices at Kumaon Himalaya, the potential of oak leaves feeding was evaluated in six native heifers (Bos indicus; 101.5 kg BW, 18-24 months) in a partial switch-over design involving two animals each on each treatment at a time. The feeding treatments involved high and low levels of oak leaves (Quercus leucotrichophora, oak leaves (OL)) supplemented to local mixed grass hay (GH) which were GH (G1), GH + low level (42.5 %) of OL (G2) and GH + high level (63.6 %) of OL (G3). The feeding trial for each treatment was conducted for 40 days that ended with a digestibility trial of 6-day duration. The dry matter (DM) intake (kg/day) was non-significantly higher in G3 (3.52) than G2 (3.11) and G1 (2.96). Intake of crude protein (CP) (g/day) was significantly (P cattle on GH alone was lacking in both energy and protein for sustaining minimum levels of production, whereas in combination with OL at 36.4:63.6 ratios supported minimum level of production (ADG 300 g) with near nutritional adequacy for major nutrients (CP, DCP, TDN, ME) but with a caution for the minor nutrients like calcium and phosphorus that need to be supplemented. PMID:22576275

Paswan, Vinod Kumar; Sahoo, Artabandhu

2012-12-01

11

Potential theory—selected topics  

CERN Document Server

The first part of these lecture notes is an introduction to potential theory to prepare the reader for later parts, which can be used as the basis for a series of advanced lectures/seminars on potential theory/harmonic analysis. Topics covered in the book include minimal thinness, quasiadditivity of capacity, applications of singular integrals to potential theory, L(p)-capacity theory, fine limits of the Nagel-Stein boundary limit theorem and integrability of superharmonic functions. The notes are written for an audience familiar with the theory of integration, distributions and basic functional analysis.

Aikawwa, Hiroaki

1996-01-01

12

Export market potential for selected horticultural crops  

International Nuclear Information System (INIS)

This paper examines the feasibility of utilising an irradiation plant to disinfest fresh fruit and vegetables destined for export markets. It examines the export market potential of selected crops with the prime view of estimating likely trends in export markets in the future. These trends will have a significant bearing on throughput levels, and hence on the economic viability of an ionising energy plant

13

Inheritance of earthquake hazard from suturing: the Himalayas as an analogue for the structural architecture and seismic potential of the Greater Caucasus  

Science.gov (United States)

The nascent collision between the Arabian and Eurasian continents has created the second-largest active collisional orogen on Earth and provides a rare opportunity to investigate how structures formed during initial suturing influence and even control the subsequent first-order structural architecture of the evolving orogen. Between the Caspian and Black Seas, the Greater Caucasus Mountains form both the northern margin of the Arabia-Eurasia collision and the main locus of orogen-perpendicular shortening, despite being located some 700 km north of the Bitlis suture. A better understanding of active structures in the range is critical for understanding the mechanics and evolution of this collisional orogen. Developing such a structural model of the Greater Caucasus is also essential for assessing earthquake hazards. Here we begin to address these problems by using geologic maps, digital topographic data, and structural measurements to create preliminary geologic cross sections across the southern flank of the central and western Greater Caucasus. These sections span both a low-elevation foreland fold-thrust belt in the south and the main topographic front of the range ~15-40 km to the north. In addition, we investigate active deformation using topographic surveys of river terraces in the foreland south of the western Greater Caucasus range front near the city of Zugdidi. Based on these observations, we suggest that the neotectonic architecture of the range is broadly analogous to that of the Himalayas, where active deformation is not focused along a range-front-defining fault but instead is localized tens of kilometers to the south, along the south edge of a low-elevation, low-relief foreland fold-thrust belt. We infer that active faults within the fold-thrust belt sole into a shallow (~5-10 km deep), north-dipping basal decollement that roots into a crustal-scale ramp which lies beneath the main topography of the Greater Caucasus. Based on prior work on the regional geology of the range, we hypothesize that this geometry results from the Cenozoic closure of a relict Mesozoic ocean basin within the Arabia-Eurasia collision zone, broadly similar to the eastern Black Sea and South Caspian Basins to which it was connected. A new compilation of earthquake records from local seismic networks shows that the central and eastern Greater Caucasus Mountains are underlain by a northeast-dipping subducted slab, likely resulting from closure of this relict back-arc basin. Himalayan-style tectonism along the northern edge of the Arabia-Eurasia collision could potentially dictate the location, magnitude, and recurrence of seismicity in the Caucasus region, and as such has significant potential for seismic hazard assessment here. Rather than solely occurring on the main thrust within the range, this model suggests that significant earthquakes may occur within the fold-thrust belt and on a basal decollement that connects them to structures within the main range. Much of the region's population, including the Georgian capital city of Tbilisi, is found within or near the foreland fold-thrust belt.

Trexler, C.; Cowgill, E.; Forte, A. M.; Mumladze, T.; Sokhadze, G.; Elashvili, M.; Niemi, N. A.

2013-12-01

14

Limit of strain partitioning in the Himalaya marked by large earthquakes in western Nepal  

Science.gov (United States)

Great earthquakes and high seismic risk in the Himalaya are thought to be focussed near the range front, where the Indian Plate slides beneath the mountain range. However, the Himalaya is curved and plate convergence becomes increasingly oblique westwards. Strain in the western Himalaya is hypothesized to be partitioned, such that western parts move northwestwards with respect to the central Himalaya. Here we use field data to identify a 63-km-long earthquake rupture on a previously unrecognized fault in the western Himalaya, far from the range front. We use radiocarbon dating to show that one or more earthquakes created 10m of surface displacement on the fault between AD 1165 and 1400. During this time interval, large range-front earthquakes also occurred. We suggest that the active fault we identified is part of a larger fault system, the Western Nepal Fault System, which cuts obliquely across the Himalaya. We combine our observations with a geodynamical model to show that the Western Nepal Fault System marks the termination of the strain-partitioned region of the western Himalaya and comprises a first-order structure in the three-dimensional displacement field of the mountain range. Our findings also identify a potential seismic hazard within the interior of the Himalaya that may necessitate significant changes to seismic hazard assessments.

Murphy, M. A.; Taylor, M. H.; Gosse, J.; Silver, C. R. P.; Whipp, D. M.; Beaumont, C.

2014-01-01

15

Forest tree species discrimination in western Himalaya using EO-1 Hyperion  

Science.gov (United States)

The information acquired in the narrow bands of hyperspectral remote sensing data has potential to capture plant species spectral variability, thereby improving forest tree species mapping. This study assessed the utility of spaceborne EO-1 Hyperion data in discrimination and classification of broadleaved evergreen and conifer forest tree species in western Himalaya. The pre-processing of 242 bands of Hyperion data resulted into 160 noise-free and vertical stripe corrected reflectance bands. Of these, 29 bands were selected through step-wise exclusion of bands (Wilk's Lambda). Spectral Angle Mapper (SAM) and Support Vector Machine (SVM) algorithms were applied to the selected bands to assess their effectiveness in classification. SVM was also applied to broadband data (Landsat TM) to compare the variation in classification accuracy. All commonly occurring six gregarious tree species, viz., white oak, brown oak, chir pine, blue pine, cedar and fir in western Himalaya could be effectively discriminated. SVM produced a better species classification (overall accuracy 82.27%, kappa statistic 0.79) than SAM (overall accuracy 74.68%, kappa statistic 0.70). It was noticed that classification accuracy achieved with Hyperion bands was significantly higher than Landsat TM bands (overall accuracy 69.62%, kappa statistic 0.65). Study demonstrated the potential utility of narrow spectral bands of Hyperion data in discriminating tree species in a hilly terrain.

George, Rajee; Padalia, Hitendra; Kushwaha, S. P. S.

2014-05-01

16

Potential Selectable Marker for Genetic Transformation in Banana  

Directory of Open Access Journals (Sweden)

Full Text Available Successful genetic transformation of banana requires effective selection systems. The effectiveness of kanamycin, neomycin, genetic in G-418, paromomycin, basta and hygromycin as selection agents to inhibit the growth of single meristematic buds of Pisang Rastali (AAB were evaluated. Due to the potential generation of chimeric plants containing both transformed and non-transformed in meristematic buds, the presence of an efficient refined selection system is essential in transformation studies. Single buds were cultured on solid and liquid MS media supplemented with 5 mg L-1 of BAP for a period of four weeks. Six selection agents tested each at 0, 25, 50, 100, 150, 200, 250 and 300 mg L-1. In preliminary experiment, basta and hygromycin were required at lower concentrations. Therefore, experiment was carried out at 0, 5, 10, 15, 20 and 25 mg L-1. Of six compounds tested, basta and hygromycin was suitable selection agent since it inhibits the growth of single buds at lower concentrations. However, hygromycin selection makes it the preferred selection over basta for easily scoreable phenotype and faster inhibition response of explants. Genetic in G-418 is effective than kanamycin, neomycin and paromomycin for selecting transformed plants conferring resistance to npt11 gene. The use of liquid medium containing selection agents showed effective in banana due lower concentrations required and good contact between explants and medium.

S. Sreeramanan

2006-01-01

17

Event Related Potential Analysis of Stimulus Over-Selectivity  

Science.gov (United States)

Stimulus over-selectivity is a phenomenon often displayed by individuals with many forms of developmental and intellectual disabilities, and also by individuals lacking such disabilities who are under cognitive strain. It occurs when only one of potentially many aspects of the environment controls behavior. Adult participants were trained and…

Reed, Phil; Savile, Amy; Truzoli, Roberto

2012-01-01

18

Determination of Half-wave Potentials of Selected Chlorophenols  

Scientific Electronic Library Online (English)

Full Text Available SciELO Portugal | Language: English Abstract in english Cyclic voltammetry was used in cetyltrimethylammonium bromide (CTAB) micellar solution to determine the half-wave potentials of selected chlorophenols, CPs. It is observed that all the electrochemical parameters of the studied CPs decrease with an increase in the number of chlorine atom(s) attached [...] to the parent compound. The mathematical relationship between the obtained E1/2 and the number of chlorine atoms in the parent compound is given. The formal potentials, E0', of the CPs are approximated from the obtained half-wave potentials.

M.O., Iwunze; B., Abel.

2012-09-01

19

Resource efficiency potential of selected technologies, products and strategies.  

Science.gov (United States)

Despite rising prices for natural resources during the past 30 years, global consumption of natural resources is still growing. This leads to ecological, economical and social problems. So far, however, limited effort has been made to decrease the natural resource use of goods and services. While resource efficiency is already on the political agenda (EU and national resource strategies), there are still substantial knowledge gaps on the effectiveness of resource efficiency improvement strategies in different fields. In this context and within the project "Material Efficiency and Resource Conservation", the natural resource use of 22 technologies, products and strategies was calculated and their resource efficiency potential analysed. In a preliminary literature- and expert-based identification process, over 250 technologies, strategies, and products, which are regarded as resource efficient, were identified. Out of these, 22 subjects with high resource efficiency potential were selected. They cover a wide range of relevant technologies, products and strategies, such as energy supply and storage, Green IT, transportation, foodstuffs, agricultural engineering, design strategies, lightweight construction, as well as the concept "Using Instead of Owning". To assess the life-cycle-wide resource use of the selected subjects, the material footprint has been applied as a reliable indicator. In addition, sustainability criteria on a qualitative basis were considered. The results presented in this paper show significant resource efficiency potential for many technologies, products and strategies. PMID:24361778

Rohn, Holger; Pastewski, Nico; Lettenmeier, Michael; Wiesen, Klaus; Bienge, Katrin

2014-03-01

20

Tectonic control on topographic and exhumational segmentation of the Himalaya  

Science.gov (United States)

Although the Himalayan range is commonly presented as cylindrical along-strike, geological structures, topography, precipitation, and exhumation rates as recorded by low-temperature thermochronology data all vary significantly from west to east. In particular, segments of the belt that are characterized by a clear topographic step between the Lesser and Higher Himalaya, associated with a peak in precipitation and focused exhumation (e.g. central Nepal, Himachal Pradesh) alternate with segments where the topography increases more linearly to the north, precipitation peaks at lower elevations and exhumation rates appear to be lower (e.g. western Nepal, Bhutan). The potential climatic or tectonic controls on these spatially variable topographic, precipitation and exhumational patterns have been widely discussed in recent years but remain unclear. The topographic step focussing rapid exhumation has been variably interpreted as being controlled by material movement over a mid-crustal ramp in the Himalayan basal detachment system (the Main Himalayan Thrust or MHT), or by recent out-of-sequence thrusting possibly triggered by strong erosional unloading. We have recently shown that the pattern of exhumation across the central Nepal Himalaya, as recorded by apatite fission-track thermochronology data, can be fit without invoking out-of-sequence thrusting and that the age pattern provides independent constraints on the geometry of the MHT. Inverting published low-temperature thermochronological datasets for west-central Nepal, east-central Nepal and the Bhutan Himalaya shows that lateral variations in the geometry of the MHT (in particular the presence or absence of a major mid-crustal ramp) strongly control the kinematics, exhumation history and the topography of the orogen. Where a major crustal ramp is present, the topography shows a steep gradient that focuses exhumation and orographic precipitation whereas the topography is gentler and exhumation less focused in the absence of a ramp. Our results therefore imply that along-strike climatic variations in the Himalaya respond to tectonics rather than driving it. The presence or absence of a mid-crustal ramp may be due to inherited structures on the underthrusting Indian Plate or, alternatively, may reflect transient behaviour of the accreting Lesser Himalayan thrust stack, which may oscillate between frontal accretion (without a ramp) or basal accretion in the presence of a ramp.

van der Beek, P.; Robert, X.; Mercier, J.; Braun, J.

2012-04-01

 
 
 
 
21

Imaging the Indian subcontinent beneath the Himalaya.  

Science.gov (United States)

The rocks of the Indian subcontinent are last seen south of the Ganges before they plunge beneath the Himalaya and the Tibetan plateau. They are next glimpsed in seismic reflection profiles deep beneath southern Tibet, yet the surface seen there has been modified by processes within the Himalaya that have consumed parts of the upper Indian crust and converted them into Himalayan rocks. The geometry of the partly dismantled Indian plate as it passes through the Himalayan process zone has hitherto eluded imaging. Here we report seismic images both of the decollement at the base of the Himalaya and of the Moho (the boundary between crust and mantle) at the base of the Indian crust. A significant finding is that strong seismic anisotropy develops above the decollement in response to shear processes that are taken up as slip in great earthquakes at shallower depths. North of the Himalaya, the lower Indian crust is characterized by a high-velocity region consistent with the formation of eclogite, a high-density material whose presence affects the dynamics of the Tibetan plateau. PMID:15988523

Schulte-Pelkum, Vera; Monsalve, Gaspar; Sheehan, Anne; Pandey, M R; Sapkota, Som; Bilham, Roger; Wu, Francis

2005-06-30

22

Glacier Changes in the Bhutanese Himalaya - Present and Future  

Science.gov (United States)

Glacierized change in the Himalayas affects river-discharge, hydro-energy and agricultural production, and Glacial Lake Outburst Flood potential, but its quantification and extent of impacts remains highly uncertain. Here we present conservative, comprehensive and quantitative predictions for glacier area and meltwater flux changes in Bhutan, monsoonal Himalayas. In particular, we quantify the uncertainties associated with the glacier area and meltwater flux changes due to uncertainty in climate data, a critical problem for much of High Asia. Based on a suite of gridded climate data and a robust glacier melt model, our results show that glacier area and meltwater change projections can vary by an order of magnitude for different climate datasets. The most conservative results indicate that, even if climate were to remain at the present-day mean values (1980-2000), almost 10% of Bhutan's glacierized area would vanish and the meltwater flux would drop by as much as 30%. New mapping of glacierized area from 2000-2010 shows a significant change in glacierized area of 4-6%. Thus the conservative steady-state area changes predicted by the model are already being realized. Under the conservative scenario of an additional 1°C regional warming, glacier retreat is predicted to continue until about 25% of Bhutan's glacierized area will have disappeared and the annual meltwater flux, after an initial spike, would drop by as much as 65%.

Rupper, S.; Schaefer, J. M.; Burgener, L. K.; Maurer, J.; Smith, R.; Cook, E.; Putnam, A. E.; Krusic, P.; Tsering, K.; Koenig, L.

2012-12-01

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The role of glaciers in stream flow from the Nepal Himalaya  

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Full Text Available Recent concerns related to the potential impacts of the retreat of Himalayan glaciers on the hydrology of rivers originating in the catchment basins of the Himalaya have been accompanied by few analyses describing the role of glaciers in the hydrologic regime of these mountains. This is, at least in part, a result of the relative inaccessibility of the glaciers of the Himalaya, at altitudes generally between 4000–7000 m, and the extreme logistical difficulties of: 1 reaching the glaciers, and 2 conducting meaningful research once they have been reached. It is apparent that an alternative to traditional "Alpine" glaciology is required in the mountains of the Hindu Kush-Himalaya region. The objectives of the study discussed here have been to develop methodologies that will begin to quantify the role of complete glacier systems in the hydrologic regime of the Nepal Himalaya, and to develop estimates of the potential impact of a continued retreat of these glacier, based on the use of disaggregated low-altitude data bases, topography derived from satellite imagery, and simple process models of water and energy exchange in mountain regions.

While the extent of mesoscale variability has not been established by studies to date, it is clear that the dominant control on the hydrologic regime of the tributaries to the Ganges Basin from the eastern Himalaya is the interaction between the summer monsoon and the 8000 m of topographic relief represented by the Himalayan wall. All the available evidence indicates that the gradient of specific runoff with altitude resulting from this interaction is moderately to strongly curvilinear, with maximum runoff occurring at mid-altitudes, and minima at the altitudinal extremes. At the upper minimum of this gradient, Himalayan glaciers exist in what has been characterized as an "arctic desert".

The methodologies developed for this study involve the relationship between area-altitude distributions of catchment basins and glaciers, based on Shuttle Radar Topography Mission (SRTM3 data and water and energy exchange gradients. Based on these methodologies, it is estimated that the contribution of glacier annual melt water to annual stream flow into the Ganges Basin from the glacierized catchments of the Nepal Himalaya represents approximately 4% of the total annual stream flow volume of the rivers of Nepal, and thus, is a minor component of the annual flow of the Ganges River. The models developed for this study indicate that neither stream flow timing nor volume of the rivers flowing into the Ganges Basin from Nepal will be affected materially by a continued retreat of the glaciers of the Nepal Himalaya.

D. Alford

2010-04-01

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Selection of microalgae for wastewater treatment and potential lipids production.  

Science.gov (United States)

In the present study, ten microalgal strains found in fresh and saline waters were cultured, and used to conduct batch experiments in order to evaluate their potential contribution to nutrient removal and biofuel production. The growth rate of microalgae was inversely analogous to their initial concentration. Three freshwater strains were selected, based on their growth rate, and their behavior with synthetic wastewater was further investigated. The strains studied were the Scenedesmus rubescens (SAG 5.95), the Neochloris vigensis (SAG 80.80), and the Chlorococcum spec. (SAG 22.83), and higher growth rate was observed with S. rubescens. Total phosphorus removal at an initial phosphate concentration of 6-7 mg P/L in the synthetic wastewater, was 53%, 25% and 11% for N. vigensis, Chlorococcum spec., and S. rubescens, respectively. Finally, the lipid content was determined at 20th and 30th day of cultivation, and the highest amount was observed at the 20th day. PMID:23994695

Aravantinou, Andriana F; Theodorakopoulos, Marios A; Manariotis, Ioannis D

2013-11-01

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Selection of enterococci for potential canine probiotic additives.  

Science.gov (United States)

Enterococci are important inhabitants of animal intestine and are widely used in probiotic products. A potentially successful probiotic strain is expected to have several desirable properties in order to be able to exert its beneficial effects. Forty enterococcal isolates from dog faeces were tested for characters believed to be important for probiotic strains; bacteriocin production, resistance or tolerance to antibiotics, low pH, bile tolerance and adhesive activity. The total count of enterococci was found to be 3.3-7.3log(10)CFU/g of faeces. Most identified strains were Enterococcus faecium. All strains were sensitive to vancomycin, ampicillin, penicillin and chloramphenicol. Thirty-three percentage of strains were resistant to erythromycin and 28% to tetracycline. Among 40 isolates, 75% showed a broad inhibitory spectrum only against Gram-positive indicator bacteria. Seven strains with broad bacteriocin activity were selected for further assays. In the presence of 1% bile, the survival rate of selected strains ranged between 72 and 98%. Survival of strains at pH 3.0 was found in the range between 76 and 87% after 3h. The adhesion of the tested strains to intestinal mucus ranged from 4 to 11% for canine mucus and from 5 to 8% for human mucus. E. faecalis EE4 and E. faecium EF01 showed the best probiotic properties. It indicates that they could be used as new candidate probiotic strains after in vivo testing. PMID:15135518

Strompfová, Viola; Lauková, Andrea; Ouwehand, Arthur C

2004-05-20

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Arc parallel extension in Higher and Lesser Himalayas, evidence from western Arunachal Himalaya, India  

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The existence of E-W extensional features from northeast (NE) Himalaya is poorly documented. Our investigation in the western part of Arunachal Himalaya provides evidences of active Quaternary E-W arc-parallel extensional features in the Higher and Lesser Himalayas. They are represented by arc-perpendicular normal faults and arc-parallel sinistral strike-slip faults. We discuss the occurrences of these arc-parallel extensional features in terms of oblique convergence and radial expansion models. The partitioning of stress due to oblique convergence is argued based on evidences of left-lateral slip in NE-Himalaya, right-lateral slip in NW-Himalaya and absence of translation in the central part. The amount of arc-parallel extension in the hinterland regions is correlated to the amount of radial shortening in the foreland. The computation of arc-parallel extension in the NE Himalayan arc is carried out by defining a small-circle centered at 88°39'±0.7'E longitude and 33°40'±0.6'N latitude having a radius of 770.7 ± 15.1 km, for the segment between 92°01' and 95°16'E longitudes. The amount of arc-parallel extension estimated is ~110 km for the NE Himalayan segment. Our result agrees closely with the 104 km extension determined based on geodetically computed extension rate and age of initiation of rifting in southern Tibet.

de Sarkar, Sharmistha; Mathew, George; Pande, Kanchan

2013-06-01

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Evolution of earthquake-triggered landslides in the Kashmir Himalaya, northern Pakistan  

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The influence of the 08 October 2005 Kashmir earthquake and subsequent snow melt and monsoon rainfall on slope stability was evaluated using repeat photography in the Kashmir Himalaya of northern Pakistan. Sixty-eight landslide-affected locations were selected and photographed in November 2005, May/June 2006, June 2007, and August 2007 to evaluate all potential geomorphic changes. Eighty percent of the locations showed no or very little change, 11% of the locations showed a partial vegetation recovery on the slopes, while 9% showed an increase in the landslide area. All those locations that showed an increase in landsliding were located along rivers and/or roads. The small change in landslide extent is remarkable given that the region experienced one of the heaviest monsoon seasons in the last decade and is counter to earlier predictions of accelerated slope erosion by landsliding in the immediate years following the earthquake. Extensive fissures and ground cracks at many localities, however, still present a potential of future landsliding under wetter conditions. ?? 2009 Elsevier B.V. All rights reserved.

Khattak, G. A.; Owen, L. A.; Kamp, U.; Harp, E. L.

2010-01-01

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Geoscientific Investigations in the Tethyan Himalayas.  

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The marine sediments of the Tibetan Tethys Himalaya investigated in the area of Gamba (South Tibet) comprise the stratigraphic range from Upper Aptian (partly even Neocomian) to Paleocene (Ilerdian). They represent a complete record of the last stage of the depositional and tectonic evolution along the northern continental margin of the Indian subcontinent, the passive southern margin of the Tethyan Ocean. The investigated sequence is approximately 3500 m thick. It is stratigraphically and li...

Willems, H.

1993-01-01

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Thermal characteristics of the Main Himalaya Thrust and the Indian lower crust with implications for crustal rheology and partial melting in the Himalaya orogen  

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The Main Himalaya Thrust (MHT) is the current tectonic boundary between the subducting Indian lithosphere and the overlying Himalayan orogenic prism and the Tibetan crust. We present thermo-kinematic calculations and metamorphic P-T-t paths of the Indian lower crust (ILC) that constrain the thermal structure of the MHT and the southern Tibetan crust (Lhasa Block) and explain the origin of a thin, seismic low velocity zone that was revealed by the recent Hi-CLIMB experiment from receiver functions of teleseismic waves. Northward of the Himalayas, the low velocity zone occurs within the ductile regime of the crust and is thought to extend along the MHT into the Lhasa Block. In the Lhasa Block, the low velocity zone occurs directly above the ILC. Predicted evolution of mineralogy of the ILC along its subduction P-T-t path shows that its dehydration can potentially induce wet melting within the orogenic prism above the inclined portion of the MHT. However, north of the Yarlung Tsangpo Suture (YTS) below the southern Lhasa Block, where subduction of the ILC is flat, the ILC is predicted to be anhydrous eclogite and therefore, it cannot supply H2O to the overlying crust. The seismic low velocity zone above this portion of the ILC is best explained by dehydration melting due to strain heating. The MHT there appears to be localized by the rheological contrast between the ductile lower Lhasa Block and the strong eclogitic ILC. Southward thrusting of the Himalaya orogenic prism, which contains accreted Indian upper crust, causes advection of hot middle-crustal rocks to shallower levels, thereby producing a shallow ductile regime between the Himalayas and the YTS. The shallow ductile regime is evident in the limit of upper crustal earthquake foci to shallow depths in this region.

Náb?lek, Peter I.; Náb?lek, John L.

2014-06-01

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Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India  

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The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as a major sink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon seques...

Bandana Devi; Bhardwaj, D. R.; Pankaj Panwar; Sharmistha Pal; Gupta, N. K.; Thakur, C. L.

2013-01-01

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Floristic Diversity and Distribution Pattern of Plant Communities along Altitudinal Gradient in Sangla Valley, Northwest Himalaya.  

Science.gov (United States)

Himalayas are globally important biodiversity hotspots and are facing rapid loss in floristic diversity and changing pattern of vegetation due to various biotic and abiotic factors. This has necessitated the qualitative and quantitative assessment of vegetation here. The present study was conducted in Sangla Valley of northwest Himalaya aiming to assess the structure of vegetation and its trend in the valley along the altitudinal gradient. In the forest and alpine zones of the valley, 15 communities were recorded. Study revealed 320 species belonging to 199 genera and 75 families. Asteraceae, Rosaceae, Apiaceae, and Ranunculaceae were dominant. Among genera, Artemisia followed by Polygonum, Saussurea, Berberis, and Thalictrum were dominant. Tree and shrub's density ranged from 205 to 600 and from 105 to 1030 individual per hectare, respectively, whereas herbs ranged from 22.08 to 78.95 individual/m(2). Nearly 182 species were native to the Himalaya. Maximum altitudinal distribution of few selected climate sensitive species was found to be highest in northeast and north aspects. This study gives an insight into the floristic diversity and community structure of the fragile Sangla Valley which was hitherto not available. PMID:25383363

Sharma, Pankaj; Rana, J C; Devi, Usha; Randhawa, S S; Kumar, Rajesh

2014-01-01

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Floristic Diversity and Distribution Pattern of Plant Communities along Altitudinal Gradient in Sangla Valley, Northwest Himalaya  

Science.gov (United States)

Himalayas are globally important biodiversity hotspots and are facing rapid loss in floristic diversity and changing pattern of vegetation due to various biotic and abiotic factors. This has necessitated the qualitative and quantitative assessment of vegetation here. The present study was conducted in Sangla Valley of northwest Himalaya aiming to assess the structure of vegetation and its trend in the valley along the altitudinal gradient. In the forest and alpine zones of the valley, 15 communities were recorded. Study revealed 320 species belonging to 199 genera and 75 families. Asteraceae, Rosaceae, Apiaceae, and Ranunculaceae were dominant. Among genera, Artemisia followed by Polygonum, Saussurea, Berberis, and Thalictrum were dominant. Tree and shrub's density ranged from 205 to 600 and from 105 to 1030 individual per hectare, respectively, whereas herbs ranged from 22.08 to 78.95 individual/m2. Nearly 182 species were native to the Himalaya. Maximum altitudinal distribution of few selected climate sensitive species was found to be highest in northeast and north aspects. This study gives an insight into the floristic diversity and community structure of the fragile Sangla Valley which was hitherto not available.

Rana, J. C.; Devi, Usha; Randhawa, S. S.; Kumar, Rajesh

2014-01-01

33

Tree ring imprints of long-term changes in climate in western Himalaya, India.  

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Tree-ring analyses from semi-arid to arid regions in western Himalaya show immense potential for developing millennia long climate records. Millennium and longer ring-width chronologies of Himalayan pencil juniper (Juniperus polycarpos), Himalayan pencil cedar (Cedrus deodara) and Chilgoza pine (Pinus gerardiana) have been developed from different sites in western Himalaya. Studies conducted so far on various conifer species indicate strong precipitation signatures in ring-width measurement series. The paucity of weather records from stations close to tree-ring sampling sites poses diffi culty in calibrating tree-ring data against climate data especially precipitation for its strong spatial variability in mountain regions. However, for the existence of strong coherence in temperature, even in data from distant stations, more robust temperature reconstructions representing regional and hemispheric signatures have been developed. Tree-ring records from the region indicate multi-century warm and cool anomalies consistent with the Medieval Warm Period and Little Ice Age anomalies. Signifi cant relationships noted between mean premonsoon temperature over the western Himalaya and ENSO features endorse utility of climate records from western Himalayan region in understanding long-term climate variability and attribution of anthropogenic impact. PMID:20009266

Yadav, R R

2009-11-01

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Sample Selected Averaging Method for Analyzing the Event Related Potential  

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The event related potential (ERP) is often measured through the oddball task. On the oddball task, subjects are given “rare stimulus” and “frequent stimulus”. Measured ERPs were analyzed by the averaging technique. In the results, amplitude of the ERP P300 becomes large when the “rare stimulus” is given. However, measured ERPs are included samples without an original feature of ERP. Thus, it is necessary to reject unsuitable measured ERPs when using the averaging technique. In this paper, we propose the rejection method for unsuitable measured ERPs for the averaging technique. Moreover, we combine the proposed method and Woody's adaptive filter method.

Taguchi, Akira; Ono, Youhei; Kimura, Tomoaki

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Pyrometallurgical slags as a potential source of selected metals recovery  

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Full Text Available Complex analysis of concentration and form of occurrence such metals as Zn, Pb, Fe and Cu in slags formed during a current zinc production in the Imperial Smelting Process (ISP is a possible basis for development of optimal recovery technology. For this purpose studies of slags from the current production of the Shaft Furnace Unit and of the Lead Refining of the “Miasteczko ?l?skie” Zinc Smelting Plant were carried out. The studies results show that slags includes high concentrations of: Zn from 0,064 % to 1,680 %, Pb from 10,56 % to 50,71 %, Fe from 0,015 % to 2,576 %, Cu from 7,48 % to 64,95 %, and change in a broad range. This slags show significant heterogeneity, caused by intermetallic phases (Zn - Pb, Cu - Zn, Cu - Pb formed on the surface thereof. It is so possible that slag can be a potential source of this metals recovery.

K. Nowi?ska

2014-10-01

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Timing of recent out-of-sequence active deformation in the frontal Himalayan wedge: Insights from the Darjiling sub-Himalaya, India  

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Recent studies of India-Eurasia convergence suggest that the entire convergence in the Himalayan wedge is almost exclusively accommodated along its basal detachment fault (Main Himalayan thrust, MHT) and its near-surface equivalent (Main Frontal thrust, MFT). Using direct dating of fault-zone gouge and strath terrace deposits, we conclude the following. (1) The present mountain front in the Darjiling sub-Himalaya was emplaced by ca. 40 ka. (2) Out-of-sequence deformation on surface-breaking faults north of the MFT in the Darjiling sub-Himalaya began ca. 20 ka and has probably continued since. (3) The Tista River responded to the ca. 20 ka deformation by migrating 150 m eastward (average rate ˜13 mm yr-1) and by incising 48 m vertically (average rate ˜4.4 mm yr-1), creating unpaired, disjointed strath terraces between 11.3 ± 1.3 ka and 1.4 ± 0.3 ka. Out-of-sequence, surface-breaking faults in the Himalaya indicate partial accommodation of active convergence within the Himalayan wedge. Using the results from the Bhuj earthquake of 2001, we suggest that active deformation along the out-of-sequence faults is a potential seismic hazard in the Himalaya, and Himalayan seismic hazard models must account for this. We also propose a conceptual model for active deformation in the Himalaya.

Mukul, Malay; Jaiswal, M.; Singhvi, A. K.

2007-11-01

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EVALUATION OF GARHWAL HIMALAYA WILD EDIBLE TUBER DIOSCOREA DELTOIDEA  

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Full Text Available The Uttarakhand is highly enriched with edible wild tubers. Such tubers are highly potential with medicinal value and nutritional value due to the presence of bio-actives. These tubers are consumed by local inhabitants to play a significant role as supplementary food. The present study is aimed at evaluating the nutritional value, successive extraction, thin layer chromatography of medicinal plant, Dioscorea deltoidea. It is a popular wild edible tubers bearing plant of Indian Himalaya having good nutritional and medicinal potential. These will be the best source of the nutraceuticals. Since tubers are richer in micronutrients and bioactive secondary metabolites, The medicinal plant tuber contain ash value, (total ash 3.34 ± 0.15%, moisture 58.92±0.10%, crude fat 0.60±0.20% and crude fiber 7.50±0.14%, the successive extractive values were studied fresh part weight. The preliminary phytochemical analysis test showed the presence of carbohydrates and glycosides, alkaloid, flavonoids, saponins, tannins, unsaturated triterpenoids and sterol, resin.

Chandra Subhash

2012-03-01

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Landscape drivers, signatures, and erosion rates from the western Himalaya using detrital Beryllium-10  

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The Himalaya represents one of the most dynamic orogenic systems on the planet. Characterized by both large tectonic and climatic gradients, the Himalaya has been used as a proving ground over the last decade to test contrasting theories about the relative role climate and tectonics play in driving overall landscape form and sediment flux in active mountain belts. Despite considerable efforts to date, results remain contradictory and are further complicated by the inherent dependence between precipitation and topography in orogenic systems. In this study we seek to shed additional light on this debate using a combination of satellite derived data (TRMM rainfall, Landsat land cover, Google Earth-derived channel widths), digital elevation model landscape metrics (normalized channel steepness indices, width-adjusted specific stream power, hillslope angles), existing apatite fission track ages, and ~65 new detrital Beryllium-10 erosion-rate estimates spread across the Ganges and Mahakali watersheds in the western Himalaya. This dataset represents one of the largest detrital CRN studies to date in the Himalaya and argues for dominant tectonic control of sediment flux in the region. Comparisons of erosion-rate estimates with established landscape metrics is in agreement with recently published relationships from other mountain belts and argues against a large-scale precipitation-modulated landscape signature. This finding is evidenced by 1) a general increase in mean hillslope and normalized channel steepness values with increasing precipitation, 2) a lack of coincidence between high erosion rates and precipitation amount or intensity, and 3) spatial coincidence between erosion rates, known tectonic units, and apatite fission-track ages. Whereas these data do not require or demonstrate a clear precipitation dependence, we do acknowledge that they allow for this potential, especially within distinct tectonic regimes where sufficient erosion rate-landscape metric scatter may mask more subtle precipitation driven trends and overprints. This analysis provides a detailed view into the spatial variability of erosion across a large region of the Himalaya at the centennial to millennial timescale (apparent erosion rates range from 0.1 to 7 mm/yr) and should provide key insights for future debates about the relative contributions of climate and tectonics in active orogenic evolution.

Fisher, G.; Bookhagen, B.; Burbank, D. W.; Whipple, K. X.; Godard, V.

2013-12-01

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Measurement of radon concentration in groundwater of Kumaon Himalaya  

International Nuclear Information System (INIS)

In this study, radon concentration in springs and hand pumps of Kumaon Himalaya, India was measured using radon emanometry technique. The radon measurements were made in springs and groundwater from the hand pumps being used as drinking water sources by general population. The hand pumps and springs were selected near the dwellings and workplaces, where the general public utilizes these water sources for their daily needs. The water samples from springs were collected in an air-tight bottle from the original discharge point (outlet) of the spring having distinct geological unit and geohydrological regime. The water was transferred from discharge point of the spring to the bottom of the bottle using PVC tubing. For hand pumps, the water was pumped out for some time and the samples were collected in 1 L bottle directly from the pump outlet. After allowing the sample bottle to over flow for a while and when no bubbles were visually observed, the sample volume was reduced to a pre-marked position leaving 250 ml of air in the bottle above the water surface. The sample bottle was then connected in a close circuit with Lucas cell, hand operated rubber pump and a glass tube containing CaCl2 to absorb the moisture. The air was then circulated in close circuit for a period of 15 mm till the radon formed a uniform mixture with the air and the resulting alpha activity was recorded. The resulting numbers of the alpha counts were then converted into Bq/l by using the calibration factor 1 cpm = 0.0663 Bq/l. The results of radon measurements in springs and hand pumps from the study area are given. Field measurements were taken in different geological units of Kumaun region in Himalaya. The radon concentration in spring water varies from 1 Bq/l to 76 Bq/l with geometric mean 10 Bq/l, whereas in hand pumps it varies from 3 Bq/l to 392 Bq/l with geometric mean of 40 Bq/l. The higher values of radon in the water samples of hand pumps are possibly because of its greater depth, which allows water to interact with a greater thickness of aquifer and thus more radon is expected in hand pumps and tube wells. Radon level was found higher in the area consisting of granite, quartz porphyry, schist, phyllites states and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks

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Metabolic Potential of the Deep Subseafloor at Selected Convergent Margins  

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The cold subseafloor is an extreme environment in which microbial metabolism appears to operate slowly but persistently over space and time. At convergent margins, subseafloor microbial communities experience diffuse flow of aqueous fluids through sediment interstices and variable flow of deeply sourced, advecting fluids. When these fluids mix, geochemical disequilibria are established, and may serve as energy sources in microbial metabolism. This study contrasts the metabolic potential of four near trench sedimentary environments associated with the Costa Rica, Cascadia, Nankai, and Izu-Bonin-Marianas subduction zones, which span much of the global range of water depths (~ 2500 to ~ 5800 m) and thermal structure (heat flow at seafloor ~ 15 to ~ 140 mW/m2) outboard of subduction zones. Geochemical data (pH, NH4+, Na+, K+, Fe2+, Ca2+, Mg2+, HCO3-, Cl-, SO42-, SiO2 (aq), CH4 (aq), H2 (aq), PO43-, HS-, and CH3COO-) collected during Ocean Drilling Program Legs 146, 170, 185, 190, and 201 are used in Gibbs free energy minimization calculations to model the bioenergetic potential of key metabolic reactions. At the four sites, pH values are 7.3-8.2, alkalinity values are 1 to 24 mM, and sulfate values are 0 to 30 mM. Notable site-specific differences exist in NH4+ (ranging two orders of magnitude in concentration) and salinity (with reported values up to 40 psu at Izu). The specific reactions considered are: (1) CO2 driven methanogenesis, (2) acetate driven methanogenesis, (3) methanotrophy coupled to sulfate reduction, (4) acetate oxidation coupled to sulfate reduction, (5) acetate oxidation coupled with nitrate reduction, (6) acetate oxidation coupled with ferric iron reduction. The standard Gibbs free energies are combined with the in situ geochemical parameters to calculate overall Gibbs free energies in deep subseafloor environments. In all cases, ferric iron reduction coupled with acetate oxidation yields the greatest energy (~-1600 kJ/mol), followed by nitrate reduction coupled to acetate oxidation (~-776 kJ/mol), sulfate reduction with acetate and CO2 driven methanogenesis at roughly equivalent energetic yields (~-376 kJ/mol), methanotrophy coupled to sulfate reduction (~-224 kJ/mol), and finally acetate driven methanogenesis (~-200 kJ/mol). These reactions represent possible microbial metabolic strategies in the deep subseafloor near convergent margin trenches.

Cardace, D.; Amend, J. P.; Morris, J. D.

2005-12-01

 
 
 
 
41

Disinfection of greywater effluent and regrowth potential of selected bacteria.  

Science.gov (United States)

Chlorination and UV irradiation of RBC (rotating biological contactor)-treated light GW (greywater) was investigated. The ability of chlorine and UV to inactivate indictor bacteria (FC - Faecal Coliforms, HPC - Heterotrophic Plate Count) and specific pathogens (P.a. - Pseudomonas aeruginosa sp., S.a. - Staphylococcus aureus sp.), was assessed and their regrowth potential was examined. The RBC removed 88.5-99.9% of all four bacteria groups. Nevertheless, the treated GW had to be disinfected. Most of the chlorine was consumed during the first 0.5 h, while later its decay rate decreased significantly, leaving enough residual after 6 h to prevent regrowth and to further inactivate bacteria in the stored GW effluent. Under exposure to low UV doses (?69 mJ/cm(2)) FC was the most resistant bacteria group, followed by HPC, P.a. and S.a. Exposure to higher doses (?439 mJs/cm(2)) completely inactivated FC, P.a. and S.a., while no further HPC inactivation was observed. FC, P.a. and S.a. did not exhibit regrowth after exposure to all the UV doses applied (up to 6 h storage). HPC did not exhibit regrowth after exposure to low UV doses (19-69 mJ/cm2), while it presented statistically significant regrowth in un-disinfected effluent and after exposure to higher UV doses (147-439 mJ/cm(2)). PMID:21411943

Friedler, Eran; Yardeni, Anat; Gilboa, Yael; Alfiya, Yuval

2011-01-01

42

Spatial variability of glacier decline in the Indian and Nepalese Himalaya since the 1960s  

Science.gov (United States)

Since reaching their Little Ice Age Maximums, Himalayan glaciers have generally undergone a period of retreat, evident from large moraines left at former ice limits. Currently, however, detailed assessments of Himalayan glacier fluctuations over the past century are limited and fail to compare spatially or temporally to records available in Central Europe, North America and Scandinavia. Consequently, the variability and magnitude of glacial change across the Himalayas, a region that is typified by complex climatic settings, is still yet to be fully understood. Against a back drop of poor data availability, 1960s Corona stereo-imagery and historic GLIMS glacier outlines now offer an opportunity to assess glacier extent in regions of the Himalayas pre-1980. Comparing glacier measurements derived from Corona and GLIMS datasets with those made from more contemporary ASTER data, changes in glacier area and length, between the 1960/70s and 2000s, were quantified for selected glaciers located in Uttaranchal, India (Bhagirathi and Pindar/Kali basins) and Central Nepal (Seti and Trisula basins). Most notably, results indicate that glaciers selected in the Bhagirathi and Pindar/Kali basins reduced in area by 7.97% and 7.54%, respectively. Contrastingly, glaciers located in the Seti and Trisula basins experienced a significantly higher rate of decline, reducing in area by 29.78% and 50.55%, respectively. After reviewing other Himalayan glacier change records, it is suggested that the comparatively limited decline of Uttaranchal glaciers may be attributed to the existence of a climatic transitional zone in this region where glaciers benefit from large amounts of both summer and winter snowfall enabling them to greater withstand recent climate changes. The spatial variability of glacier decline shown here has important implications when considering the future impacts of continued retreat on regional water resources across the Himalaya.

Wilson, R.; Rivera, A.; Collins, D. N.; Entwistle, N. S.

2013-12-01

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Prospects of Sustainable Livestock Farming in the Uttarakhand Himalaya, India  

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Full Text Available Livestock farming forms an integral part in the economy of the Uttarakhand Himalaya and plays an important role in the mixed crop farming system. In addition, high diversity in livestock composition is the characteristic features of the mainland of Uttarakhand. The state obtains high potential of milk production because of availability of fodder as a form of extensive grasslands, which are locally known as bugyals or kharaks and fodder trees. Livestock, other than milk production, are widely used for manure, plowing fields and transportation of goods. The availability of extensive grasslands and feasible climatic conditions manifest a way for sustainable livestock farming in Uttarakhand, particularly in the temperate zone between 1400 m and 2200 m, where production of milk is high. Valley regions are generally known for rearing of drought animals with low milk producing capacity. This paper aims to discuss on the prospects of sustainable livestock farming and to trace the temporal changes that took place over the past years in terms of livestock population, composition, and the governmental policies and planning for developing livestock sector. It draws implications on these experiences for livestock planners and policy-makers and raises several research issues related to livestock sector development.

V. P. Sati

2010-01-01

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Global warming may lead to catastrophic floods in the Himalayas  

International Nuclear Information System (INIS)

In Nepal, data from 49 surveillance stations show that there has been a distinct temperature increase since the middle of the 1970s, the greatest changes being on the highest summits. When lakes overfill and beaches threaten to break down, this is a result of the global warming that melts the glaciers. The glaciers in Bhutan are observed to decrease by 30 - 40 metres per year, in some years as much as 100 metres. In the village of Tribeni an advanced warning system has been established to warn the 10 000 inhabitants of a potential flood from Lake Tsho Rolpa 108 km upstream. Research from the Himalayas also point to another serious threat. The melting threatens not only human lives, tourism, foot paths, roads, bridges and power stations. Since the mountains are the water towers of the world, filling rivers and lakes with water upon which all life depends, continued shrinking of the world's glaciers as is now observed will cause many rivers and fresh-water systems to dry out. Researchers from the UN Unep programme and International Centre for Integrated Mountain Development have registered at least 44 glacier lakes that are increasing so fast that they may cause outburst floods within five years. Similar investigations are being planned in India, Pakistan and China

45

Variations in radon concentration in groundwater of Kumaon Himalaya, India  

International Nuclear Information System (INIS)

The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya (India)) was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq I-1 with a mean of 50 Bq I-1 in groundwater in different litho-tectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks. (authors)

46

Streaming potentials in gramicidin channels measured with ion-selective microelectrodes.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Streaming potentials have been measured for gramicidin channels with a new method employing ion-selective microelectrodes. It is shown that ideally ion-selective electrodes placed at the membrane surface record the true streaming potential. Using this method for ion concentrations below 100 mM, approximately seven water molecules are transported whenever a sodium, potassium, or cesium ion, passes through the channel. This new method confirms earlier measurements (Rosenberg, P.A., and A. Finke...

Tripathi, S.; Hladky, S. B.

1998-01-01

47

Constraints and prospects of uranium exploration in Himalaya  

International Nuclear Information System (INIS)

Exploration for uranium in the Himalaya over the last thirty years has brought to light five distinct types of mineralisation, namely, vein-type, hydrothermal shear controlled-type, disseminated-type, syngenetic-type, and sandstone-type. The first three are associated with lower to middle proterozoic metasedimentary rocks, metabasic rocks, and granitoids of the lesser Himalaya in close proximity to the main central thrust (MCT). The carbonaceous slates of Haimanta group (late proterozoic to eocambrian) and the Mussoorie phosphorites (eocambrian) represent the syngenetic types. The sandstone-type is associated with the late tertiary Siwaliks of the northwestern Himalaya. The constraints in geology and uranium exploration in the Himalaya have been briefly discussed and principal uranium occurrences in relation to their tectonic environment and genesis listed. The need for geochemical characterization of the Himalayan granitoids and the metabasics related to known uranium mineralisation and new areas have been suggested. Integrated application of radiometric, geochemical and geophysical methods of prospecting and remote sensing techniques in regional geological correlation, identification of subtle rock alterations associated with mineralized zones, geologic structures, and deep crustal lineaments have been advocated. A case for the exploration of the areas of lesser Himalaya outside the MCT has been made out so as to locate hitherto unknown types of uranium deposits incerto unknown types of uranium deposits including, strata bound, metamorphic, and intra granitic types, possibly with better depth persistence. (author). 57 refs., 1 fig., 2 tabs

48

Growth Characteristics, Biomass and Chlorophyll Fluorescence Variation of Garhwal Himalaya’s Fodder and Fuel Wood Tree Species at the Nursery Stage  

Directory of Open Access Journals (Sweden)

Full Text Available Fodder and fuel wood deficiency in the Himalayan region is well recognized. Rural inhabitants are exploiting these forest resources for their livelihood for generations which leads to severe deforestation. The aim of this study was to identify the fast growing fodder and fuel wood tree species of Garhwal Himalayas at nursery stage with wider relevance and great potential for extensive afforestation programmes. Seed of Bauhinia purpurea L., Bauhinia retusa Roxb., Bauhinia variegate L., Celtis australis L., Ficus nemoralis Wall., Ficus roxburghii Wall., Grewia optiva Drummond, Leucaena leucocephala (Lam. de Wit, Melia azedarach L., Ougeinia oojeinensis (Roxb. Hochr., Quercus leucotrichophora A. Camus, Terminalia alata Heyne ex Roth. and Toona ciliate M. Roem. were collected from the superior trees and seedlings were raised. After one year and one month of establishment at the nursery, the growth characteristics, biomass and chlorophyll fluorescence (dark-adopted Fv/Fm of each species were also recorded. G. optiva had shown the highest growth in terms of height, basal diameter increment and number of branches, while production of leaves was more on O. oojeinensis. Biomass and chlorophyll fluorescence (maximum quantum yield or photochemical efficiency of PSII was found highest in Q. leucotrichophora which indicates photosynthetically this species was most active among the studied fodder and fuel wood tree species. The information in this communication could be utilized for developing various conservation and sustainable strategies in the Garhwal Himalayas to mitigate the<

Azamal Husen

2013-01-01

49

Treasure and Tragedy of the Kashmir Himalaya  

Directory of Open Access Journals (Sweden)

Full Text Available Biological interventions and sequential eco-edaphic changes have depleted the habitats of essential and commercially valuable medicinal plants, hence paved the way to invasive alien species, thereby infuriating the bio-resource diminution and deprivation. The present communication is an attempt to draw attention to the importance of some threatened medicinal plants of Kashmir Himalaya and the various threats they are forced upon. In total 12 species belonging to 11 families have been surveyed, assessed and analyzed for their importance and threat status. The study revealed that the already restricted populations of these threatened species are squeezed further by various natural and anthropogenic factors, above and beyond being subjected to over-exploitation. All these causative factors if not addressed without more ado, the day is not far away when this precious legacy will be lost for ever. It is indeed a grave situation for these species which calls for the recoup whatever is left. There is a buzz for the execution of global slogan and it is the need of hour to conserve these gems in today`s world of bioprospecting.

Parvaiz A. Wani

2006-01-01

50

Spring-recharging in the Himalayas  

International Nuclear Information System (INIS)

in the settlement of mountain villages in the Himalayas. In fact, in many places, it was the single factor that determined the location of the villages and naturally rainwater has been the source which recharge the catchments of the springs. Forest cover keeps these catchment areas alive for the slow and constant recharging of the springs. In the recent past due to continuous deforestation, the catchment areas have been drastically reduced. Eventually, these denuded lands were unable to conserve water, which has resulted in the drying-up and dying of many mountain springs. Certainly, this became a major threat to both the natural habitats of the springs, as well as to the survival of the communities. In order to meet the water needs of the villages, the government-development agencies devised a distribution system in which water was diverted from regions with an adequate supply to those deprived of water. This approach to remedy the water shortage brought about significant water conflicts, as the rights to water resources were not well defined. This system also did not adequately address water-management and distribution lines for the water resources

51

Decrease, Increase or Stability? Glacier Response to Climate Change in the Trans-Himalayas of Ladakh, Northern India  

Science.gov (United States)

The eastern and central parts of the Greater Himalayas display a general picture of rapidly melting glaciers, whereas the glaciers in the western Himalayas, Hindu Kush and Karakorum show a more differentiated response to climate change. It includes individual advancing glaciers and relatively stable snout positions. The Trans-Himalayan region of Ladakh is possibly located at the interface between shrinking and advancing or stable glaciers. The region is characterized by cold and arid conditions (mean annual air temperature amounts 5.6 °C and precipitation 93 mm in Leh, 3545 m a.s.l.), while the influence of the monsoon is rather limited. Due to low summer precipitation and the variability of winter snow fall, glaciers largely determine the potentials and limitations of irrigated crop cultivation, forming the primary basis of subsistence agriculture and regional food security. The glaciers of Ladakh are located above 5200 m a.s.l. and according to their small size (generally less than 2 km²), their response to climate change is expected to be direct and predictable. To detect and to quantify glacier changes in different aspects of the NNW-SSE oriented Kang Yatze Massif (6401 m a.s.l.), which is sandwiched between the Zanskar and Stok Ranges, multi-temporal and multi-scale remote sensing data were used. In order to map the changes of glacier covered areas two panchromatic Corona images from 1969 were compared to a high resolution panchromatic Worldview image from 2009. The data gap of the 40 years period was filled with Spot images (1991, 2006), and several Landsat and Aster data. To identify and quantify the glacierized areas a semi-automatic thresholding approach was applied for the co-registered multi-spectral datasets. Additionally, the delineation of glaciers was manually digitized on the panchromatic images. First results for the time period between 1969 and 2009 reveal a minor decrease of almost all investigated glaciers in the Kang Yatze Massif. In order to embed the results into the regional scale of the upper Indus catchment three other study areas of the Stok and Ladakh Ranges in the northern vicinity were integrated. The relative stability of seasonal glacier runoff patterns can further be validated by regional land use and land cover development. Selected multi-temporal studies of cultivated areas in the tributaries between 1969 and 2006 reveal a high grade of persistence. The remote sensing results were validated by three field campaigns which were carried out between 2007 and 2009.

Schmidt, Susanne; Nüsser, Marcus

2010-05-01

52

Changing glacial lakes and associated outburst floods risks in Nanda Devi Biosphere Reserve, Indian Himalaya  

Science.gov (United States)

Glacial lakes and associated outburst floods (GLOFs) have increased in the Himalayan region due to climate change during the last century that has led to huge losses to society. Therefore, the present study was undertaken to map glacial lakes, their increasing extent, and associated damage potential in Nanda Devi Biosphere Reserve (NDBR), Indian Himalaya. The glacial lakes were mapped on Landsat TM (3 November, 2009 and 6 November 2010) and Landsat MSS satellite images (15 November 1976 and 26 October 1979) to assess their changing area. Potential GLOFs sites have been identified and studied for their damage potentials using site characteristics and past occurrence of GLOFs. A total of 35 lakes were mapped, of which 14 lakes are located at more than 4500 m. The size and damage potentials of lakes have increased. Some lakes grew so much that they merged to form a big lake. All of these are potential GLOFs and can cause severe damage to society.

Mal, S.; Singh, R. B.

2014-09-01

53

Temporal and spatial variations in erosion rate in the Sikkim Himalaya as a function of climate and tectonics  

Science.gov (United States)

The Tista River is a major tributary of the Brahmaputra drainage system (Eastern Himalaya). Its headwaters are located in the glaciated northernmost parts of the Sikkim and its catchment area amounts to more than 12,000 km2 including a depositional megafan (extending mostly in Bangladesh and West Bengal-India). The Tista has recently incised its megafan at the topographic front of the mountain range by about 30 meters. Neither the timing of deposition/incision of the megafan sediments, nor the erosion rates of the source areas as well as their potential relationships, have been investigated in detail. Comparing these data is essential to distinguish between a climatic and/or tectonic control of the evolution of the Sikkim Himalaya and piedmont. To constrain erosion rates in the hinterland at different temporal scales (respectively millenial and geological timescales), we report cosmogenic nuclide (10Be) and thermochronological (apatite fission-tracks) data on modern river sands. Results were mapped to evidence spatial variations of erosion/exhumation rates in the Tista catchment. Cosmogenic nuclides were also used to date the onset of incision of the megafan and relate it to potential changes in hinterland erosion. In addition, isotope geochemistry (?Nd and 87Sr/86Sr) performed on modern river sands and Late-Quaternary megafan sediments allows characterizing the isotopic signature of the different source areas and constraining variations in provenance of the Tista megafan deposits through time in response to changing climatic conditions. Results show that the Tista fan deposits are mainly sourced from the High Himalayan Crystalline domain with excursions more influenced by the Lesser Himalaya domain. These data provide a new comprehensive view on modern erosion and long-term exhumation of the Sikkim Himalaya. This study of a "closed system" will help our knowledge and understanding of erosional processes and sediment fluxes in mountainous environments as a function of climate and tectonics.

Abrahami, Rachel; Huyghe, Pascale; van der Beek, Peter; Carcaillet, Julien

2014-05-01

54

Rapid response to selection, competitive release and increased transmission potential of artesunate-selected Plasmodium chabaudi malaria parasites.  

Science.gov (United States)

The evolution of drug resistance, a key challenge for our ability to treat and control infections, depends on two processes: de-novo resistance mutations, and the selection for and spread of resistant mutants within a population. Understanding the factors influencing the rates of these two processes is essential for maximizing the useful lifespan of drugs and, therefore, effective disease control. For malaria parasites, artemisinin-based drugs are the frontline weapons in the fight against disease, but reports from the field of slower parasite clearance rates during drug treatment are generating concern that the useful lifespan of these drugs may be limited. Whether slower clearance rates represent true resistance, and how this provides a selective advantage for parasites is uncertain. Here, we show that Plasmodium chabaudi malaria parasites selected for resistance to artesunate (an artemisinin derivative) through a step-wise increase in drug dose evolved slower clearance rates extremely rapidly. In single infections, these slower clearance rates, similar to those seen in the field, provided fitness advantages to the parasite through increased overall density, recrudescence after treatment and increased transmission potential. In mixed infections, removal of susceptible parasites by drug treatment led to substantial increases in the densities and transmission potential of resistant parasites (competitive release). Our results demonstrate the double-edged sword for resistance management: in our initial selection experiments, no parasites survived aggressive chemotherapy, but after selection, the fitness advantage for resistant parasites was greatest at high drug doses. Aggressive treatment of mixed infections resulted in resistant parasites dominating the pool of gametocytes, without providing additional health benefits to hosts. Slower clearance rates can evolve rapidly and can provide a strong fitness advantage during drug treatment in both single and mixed strain infections. PMID:24763470

Pollitt, Laura C; Huijben, Silvie; Sim, Derek G; Salathé, Rahel M; Jones, Matthew J; Read, Andrew F

2014-04-01

55

Potential site selection for radioactive waste repository using GIS (Study area: Negeri Sembilan) - Phase 1  

International Nuclear Information System (INIS)

The main purpose in this paper is to create the Geographic Information System (GIS) based analysis on the potential site area for near-surface radioactive waste repository in the state of Negeri Sembilan. There are several parameters should be considered related to the safety assessment in selecting the potential site. These parameters such as land-use, urban area, soil, rainfall, lithology, lineament, geomorphology, landslide potential, slope, elevation, hydrogeology and protected land need to be considered before choosing the site. In this phase, we only consider ten parameters for determining the potential suitable site. (author)

56

Selection of potential pollinizers for ‘Hass’ avocado based on flowering time and male-female overlapping  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Avocado production is dependent on the singular synchronous protogynous dichogamy of the species that promotes outcrossing. With the objective of selecting potential pollinizer avocado genotypes for ‘Hass’, the most important avocado cultivar worldwide, we have monitored during two consecutive years the flowering phenology of 27 avocado genotypes in Southeastern Spain.

Alcaraz, M. L.; Hormaza, Jose? Ignacio

2009-01-01

57

Are northeast and western Himalayas earthquake dynamics better "organized" than Central Himalayas: An artificial neural network approach  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish Los Himalayas entre los 20 y 38 grados de latitud N y los 70 a 98 grados de longitud E están entre las regiones más activas y vulnerables a los temblores en el mundo. Se examina la evolución de la sismicidad en el tiempo (M > 4) en los Himalayas centrales, occidentales y del Noreste para el interval [...] o de 1960-2003 utilizando el método de redes neuronales artificiales (ANN). El modelo de capas múltiples sirve para simular la frecuencia de sismos con una resolución mensual. Para el entrenamiento del ANN se utiliza un algoritmo de propagación en reversa con optimización de gradiente, y se generaliza el resultado con validación cruzada. Se concluye que las tres regiones se caracterizan por procesos que evolucionan en un plano multidimensional caótico similar a una dinámica auto-organizada. El sector central posee un coeficiente de correlación más bajo que las otras dos regiones, que parecen estar mejor "organizadas", lo que es consistente con la información geológica y tectónica disponible. Abstract in english The Himalaya covering 20-38° N latitude and 70-98° E longitude, is one of the most seismo-tectonically active and vulnerable regions of the world. Visual inspection of the temporal earthquake frequency pattern of the Himalayas indicates the nature of the tectonic activity prevailing in this region. [...] However, the quantification of this dynamical pattern is essential for constraining a model and characterizing the nature of earthquake dynamics in this region. We examine the temporal evolution of seismicity (M > 4) of the Central Himalaya (CH), Western Himalaya (WH) and Northeast Himalaya (NEH), for the period of 1960-2003 using artificial neural network (ANN) technique. We use a multilayer feedforward artificial neural network (ANN) model to simulate monthly resolution earthquake frequency time series for all three regions. The ANN is trained using a standard back-propagation algorithm with gradient decent optimization technique and then generalized through cross-validation. The results suggest that earthquake processes in all three regions evolved on a high dimensional chaotic plane akin to "self-organized" dynamical pattern. Earthquake processes of NEH and WH show a higher predictive correlation coefficient (50-55%) compared to the CH (30%), implying that the earthquake dynamics in the NEH and WH are better "organized" than in the CH region. The available tectonogeological observations support the model predictions.

S., Sri Lakshmi; R. K., Tiwari.

2007-03-01

58

Are northeast and western Himalayas earthquake dynamics better "organized" than Central Himalayas: An artificial neural network approach  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish Los Himalayas entre los 20 y 38 grados de latitud N y los 70 a 98 grados de longitud E están entre las regiones más activas y vulnerables a los temblores en el mundo. Se examina la evolución de la sismicidad en el tiempo (M > 4) en los Himalayas centrales, occidentales y del Noreste para el interval [...] o de 1960-2003 utilizando el método de redes neuronales artificiales (ANN). El modelo de capas múltiples sirve para simular la frecuencia de sismos con una resolución mensual. Para el entrenamiento del ANN se utiliza un algoritmo de propagación en reversa con optimización de gradiente, y se generaliza el resultado con validación cruzada. Se concluye que las tres regiones se caracterizan por procesos que evolucionan en un plano multidimensional caótico similar a una dinámica auto-organizada. El sector central posee un coeficiente de correlación más bajo que las otras dos regiones, que parecen estar mejor "organizadas", lo que es consistente con la información geológica y tectónica disponible. Abstract in english The Himalaya covering 20-38° N latitude and 70-98° E longitude, is one of the most seismo-tectonically active and vulnerable regions of the world. Visual inspection of the temporal earthquake frequency pattern of the Himalayas indicates the nature of the tectonic activity prevailing in this region. [...] However, the quantification of this dynamical pattern is essential for constraining a model and characterizing the nature of earthquake dynamics in this region. We examine the temporal evolution of seismicity (M > 4) of the Central Himalaya (CH), Western Himalaya (WH) and Northeast Himalaya (NEH), for the period of 1960-2003 using artificial neural network (ANN) technique. We use a multilayer feedforward artificial neural network (ANN) model to simulate monthly resolution earthquake frequency time series for all three regions. The ANN is trained using a standard back-propagation algorithm with gradient decent optimization technique and then generalized through cross-validation. The results suggest that earthquake processes in all three regions evolved on a high dimensional chaotic plane akin to "self-organized" dynamical pattern. Earthquake processes of NEH and WH show a higher predictive correlation coefficient (50-55%) compared to the CH (30%), implying that the earthquake dynamics in the NEH and WH are better "organized" than in the CH region. The available tectonogeological observations support the model predictions.

S., Sri Lakshmi; R. K., Tiwari.

59

The hydrologic sensitivity of the upper Indus River to glacier changes in the western Karakoram Himalayas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recent controversy regarding the rates of disappearance of glaciers in the Himalayas, the world’s highest mountain chain, has primarily been focused on the eastern Himalayas. Studies carried out in the Central Karakoram Himalayan region suggest an expansion of glaciers. Little information exists about long-term glacier changes and their impact on streamflow in the Karakoram Himalayas where field surveys are difficult due to complex terrain and long term measurements have not been collected....

Naz, Bibi S.

2011-01-01

60

Bateman in nature: predation on offspring reduces the potential for sexual selection.  

Science.gov (United States)

Sexual selection is driven by competition for mates, and the advantage of a competitor is determined by the number of offspring it produces. Early experiments by Angus Bateman characterized this interaction, and the quantitative relationship between a male's number of mates and number of offspring is known as the Bateman slope. Sexual dimorphism, one of the most obvious results of sexual selection, largely requires a positive Bateman relationship, and the slope provides an estimate of the potential for sexual selection. However, natural selection from the environment can also influence male success, as can random effects, and some have argued for inclusion of the latter in calculations of mate success. Data from pronghorn (Antilocapra americana) reveal the presence of a positive Bateman slope in each year of a 10-year study. We found no evidence that random effects skewed male mating success; however, substantial yearly variation in the Bateman slope due to predation on fawns was evident. These results support the validity of the Bateman relationship, yet they also demonstrate that environmental or extrinsic influences can limit the potential for sexual selection. PMID:23139332

Byers, John; Dunn, Stacey

2012-11-01

 
 
 
 
61

Thickness of underthrust Indian crust in the Garhwal Himalaya  

Science.gov (United States)

Using common conversion point (CCP) stacking of teleseismic receiver functions (RFs), we image the Moho and Main Himalayan Thrust (MHT) beneath the Garhwal Himalaya (Alaknanda Valley, Uttaranchal, India). Beneath the Main Frontal Thrust (southern margin of the Himalaya), we image the Moho at a depth of 40 km, increasing to a depth of 55 km beneath the South Tibet Detachment (STD). These depths are shallower than the 50-55 km found c. 300 km west by the HIMPROBE team (Rai et al., GRL 2006), but are comparable to those found c. 600 km east by the HiCLIMB team (Nabelek et al., Science 2009). However, the HiCLIMB team imaged a Moho with a nearly constant dip, whereas in our region we image an apparent steepening of the Moho beneath the Greater Himalaya which accommodates most of the observed 15 km Moho depth increase. This steepening is spatially coincident with both the rise in elevation of the Tibetan plateau and with the Munsiari Thrust (MT), which we also image. The Munsiari Thrust is a brittle thrust fault that is the southern-most, structurally-lowest, and currently-active component of the Main Central Thrust (MCT) deformation zone. Beneath the Lesser Himalaya we image the MHT at a depth of 15 km and the Moho at a depth of 40 km, suggesting that the thickness of Indian continental basement subducting beneath the Himalaya in this region is as thin as 25 km. These results also suggest that ~15 km of thrust sheets lie beneath the Lesser Himalaya. Beneath the STD, this increases to ~25 km of thrust sheets. Our data are from a broadband seismic array consisting of ~20 stations with ~10 km spacing arranged linearly from SW to NE across the Himalayan thrust belt at ~80°E, from the Main Frontal Thrust (MFT) to the South Tibet Detachment (STD). The array was operated by India's National Geophysical Research Institute in 2005-2006. We generate crustal images using stacking of P-S receiver functions. We calculate receiver functions using an iterative time-domain method and depth-convert them by back propagation in an assumed velocity model, then bin and stack them to obtain two-dimensional images. Our model has a bin size of 1 km in depth and 10 km horizontally.

Caldwell, W. B.; Rai, S. S.; Ashish, A.; Klemperer, S. L.; Lawrence, J. F.

2010-12-01

62

Cycles of Sediment Aggradation and Incision in the Western Sub-Himalaya  

Science.gov (United States)

The magnitude of sediment delivery from the Himalayan mountains to the foreland, is characterized by large fluctuations on different timescales. At the first order, these fluctuations are manifested by periods of sediment aggradation, associated with the formation of large alluvial fans during times of high sediment delivery and re-incision and remobilization during reduced sediment delivery. At longer timescale (106-107 yr) sediment delivery is controlled by tectonic processes, whereas at shorter timescales (103-105 yr) climatic fluctuations such as variations in monsoonal strength or Quaternary glacial and interglacial oscillations dictate sediment production and transport. However, detailed stratigraphic information and chronologies of Quaternary sediment aggradation and incision cycles within the Sub-Himalaya are lacking and the degree of variability in sediment delivery during these episodes has remained unclear. In this study, we investigate Quaternary sediments exposed within the Sub-Himalaya of the Kangra re-entrant to the west of the Beas river. Here, the outlets of the drainage basins provide an ideal location to analyze aggradation and re-incision of transiently-stored sediments. The sediment-source region for this area is the Dhauladhar range, in the Higher Himalaya, which has been uplifting since the Late Miocene, thus restricting the potential source region for Late Cenozoic sediments supplied to the foreland. Folded and faulted Siwalik sediments of the Sub-Himalaya have formed sediment-filled intramontane piggy-back basin and have been progressively excavated. Thus far, we document a prolonged sediment-aggradation period by a thick sequence of boulder conglomerates. Subsequent re-incision of this fill, has left atleast three distinct terrace levels, which are recognized regionally at elevations ~5-10m, 65±10m and 140±10m above the present-day riverbed. The composition of the fill unit is dominated by 60% granitic clasts and is therefore distinct from the regionally exposed Siwalik conglomerates (>65% quartzite). We interpret the provenance signal to mean that the exposed lithologies in the catchment most likely had changed from quartzite-rich Higher Himalayan cover units to unroofed granites between the time of deposition of the Upper Siwalik conglomerates and sedimentary basin fill. Preliminary river profile analyses and topographic profiles along the terrace surfaces revealed tilting of some of the older, higher terrace levels in certain sections towards the north-east when compared to the gradient of the present-day river, suggesting ongoing internal shortening within the Sub-Himalaya. DEM-based geomorphic analysis, surface exposure dating and burial dating of well-shielded sediments using cosmogenic nuclides are in progress. With the expected results, we anticipate to determine the chronology of terrace levels, determine deformation rates, reconstruct the fluvial incision history and ultimately the minimum sediment-flux rate in the study area.

Dey, Saptarshi; Thiede, Rasmus; Bookhagen, Bodo; Strecker, Manfred

2013-04-01

63

Diagnostic potentialities of pneumomediastinography and selective phlebography in the evaluation of thymus evolution in myasthenia  

Energy Technology Data Exchange (ETDEWEB)

Based on an analysis of X-ray, intraoperative and histological findings in 124 operated on patients (thymectomy) with myasthenia the authors describe potentialities of pneumomediastinography (PMG) (pheumomediastinotomography-PMTG) in the determination of its main variants (hyperplasia, involution, tumor). Clear knowledge of the variants of x-ray image of the normal anatomical structures of the anterior mediastinum and age peculiarities of the thymus for correct interpretation of pneumomediastinograms is necessary. The importance of selective phlebography of the thymus for differential diagnosis of thymomas and nodular indurations of the fatty tissue in the anterior mediastinum, thymomas and fatty involution of the thymus, residual thymus and zones of fibrous-adipose tissue in the mediastinum is stressed. Selective phlebography is a simple and safe method that adds to PMG (PMTG) potentialities in the evaluation of thymus evolution in myasthenia.

Vasil' ev, V.N.; Bel' chikova, N.S.; Kuksinskij, V.E. (Leningradskij Inst. Usovershenstvovaniya Vrachej (USSR))

1983-01-01

64

Diagnostic potentialities of pneumomediastinography and selective phlebography in the evaluation of thymus evolution in myasthenia  

International Nuclear Information System (INIS)

Basing on an analysis of X-ray, intraoperative and histological findings in 124 operated on patients (thymectomy) with myasthenia the authors describe potentialities of pneumomediastinography (PMG) (pheumomediastinotomography-PMTG) in the determination of its main variants (hyperplasia, involUtion, tumor). Clear knowledge of the variants of x-ray image of the normal anatomical structures of the anterior mediastinum and age peculiarities of the thymus for correct interpretation of pneumomediastinograms is necessary. The importance of selective phlebography of the thymus for differential diagnosis of thymomas and nodular indurations of the fatty tissue in the anterior mediastinum, thymomas and fatty involution of the thymus, residual thymus and zones of fibrous-adipose tissue in the mediastinum is stressed. Selective phlebography is a simple and safe method that adds to PMG (PMTG) potentialities in the evaluation of thymus evolution in myasthenia

65

Fault delineation study using soil-gas method in the Dharamsala area, NW Himalayas, India  

International Nuclear Information System (INIS)

Soil-gas activity in the vicinity of neotectonic fault zones within the Dharamsala area in the region of the NW Himalayas, India, has been investigated by determining enhanced concentration values of radon and helium in the soil, using an ionization chamber and an ASM 100 HDS (Alcatel), respectively. A geological map of the area was used for site selection and to locate the predicted courses of faults. Elevated levels of radon and helium in the soil gas were found along a profile of a major fault (MBT-2). Radon shows variation not only due to the tectonic structures but also due to change in lithology. Helium and radon anomalies together show that apart from conspicuous thrust MBT-2, the area under study is cut across by the N-S transverse faults/lineaments

66

Identification of selective tubulin inhibitors as potential anti-trypanosomal agents.  

Science.gov (United States)

The potency of a series of sulfonamide tubulin inhibitors against the growth of Trypanosoma brucei (T. brucei), as well as human cancer and primary fibroblast cells were evaluated with the aim of determining whether compounds that selectively inhibit parasite proliferation could be identified. Several compounds showed excellent selectivity against T. brucei growth, and have the potential to be used for the treatment of Human African trypanosomiasis. A T. brucei tubulin protein homology model was built based on the crystal structure of the bovine tubulin. The colchicine-binding domain, which is also the binding site of the tested sulfonamide tubulin inhibitors, showed clear differences between the tubulin structures and presumably explained the selectivity of the compounds. PMID:22850214

Lama, Rati; Sandhu, Ranjodh; Zhong, Bo; Li, Bibo; Su, Bin

2012-09-01

67

MATERIALS SELECTION FOR THE ZETA POTENTIAL QUALITY-CONTROL OF SOLID SURFACES  

Digital Repository Infrastructure Vision for European Research (DRIVER)

MATERIALS SELECTION FOR THE ZETA POTENTIAL QUALITY-CONTROL OF SOLID SURFACES Abstract Reliable results of measurements can only be assured by using faultless measuring instruments, the efficiencies of which do, regrettably, deteriorate over time and usage. The correct functioning of instruments can be examined using reference materials. The SurPASS electrokinetic analyser, which has only been on the market for a relatively short time, is also subject to different influences and therefo...

Rudas?, Manuela

2010-01-01

68

Characterization of N200 and P300: Selected Studies of the Event-Related Potential  

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The Event-Related Potential (ERP) is a time-locked measure of electrical activity of the cerebral surface representing a distinct phase of cortical processing. Two components of the ERP which bear special importance to stimulus evaluation, selective attention, and conscious discrimination in humans are the P300 positivity and N200 negativity, appearing 300 ms and 200 ms post-stimulus, respectively. With the rapid proliferation of high-density EEG methods, and interdisciplinary interest in its...

Patel, Salil H.; Azzam, Pierre N.

2005-01-01

69

Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei sub...

Argyri, Anthoula; Zoumpopoulou, Georgia; Karatzas, Kimon Andreas; Tsakalidou, Effie; Nychas, George John; Panagou, Efstathios; Tassou, Chrysoula

2012-01-01

70

Potential and Structural Variation of Some Selected Cultivated Bamboo Species in Peninsular Malaysia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Screening of different cultivated bamboo species to find out potential variety of bamboo is most important. Structural variations in term of anatomy, physical and strength properties of 3 year-old cultivated Gigantochloa brang, G. levis, G. scotechinii and G. wrayi were investigated for screening purposes. The culms of these bamboos were selected, harvested and processed for subsequent studies. The results show that each species exhibited differences in the...

Razak Wahab; Mohd Tamizi Mustafa; Mohammed Abdus Salam; Tabert, Tamer A.; Othman Sulaiman; Mahmud Sudin

2012-01-01

71

Integrated Natural Resource Management: Approaches and Lessons from the Himalaya  

Directory of Open Access Journals (Sweden)

Full Text Available Losses of forest cover, biodiversity, agricultural productivity, and ecosystem services in the Himalayan mountain region are interlinked problems and threats to the sustainable livelihoods of 115 x 106 mountain people as well as the inhabitants of the adjoining Indo-gangetic plains. Until the 1970s, environmental conservation, food security, and rural economic development were treated as independent sectors. The poor outcomes of sector-oriented approaches catalyzed efforts to address environmental and socioeconomic problems concurrently. The identification of "key" natural resource management interventions is an important dimension of integrated management. Projects to rehabilitate the degraded lands that cover 40% of the Indian Himalaya could be key interventions provided that they address both socioeconomic and environmental concerns across spatial and temporal scales. However, projects of this type, e.g., investments in conifer plantations on degraded forest lands, have failed because their designs did not take into account the needs of local residents. This study illustrates a case of land rehabilitation in a small isolated village close to the alpine zone. Vital elements of this project strategy included identifying local perceptions and knowledge and involving the local people in the selection and implementation of the interventions needed to restore the land. Communities were found to be more concerned with the immediate economic benefits from bamboo and medicinal species than the long-term benefits of tree planting. The villagers eventually reached a consensus to plant broadleaved multipurpose trees in association with bamboo and medicinal species. Despite assurances that all the economic benefits from rehabilitation would go to the community, the people would not agree to voluntary labor, although they did absorb significant costs by providing social fencing, farmyard manure, and propagules from community forests. Households shared costs and benefits according to traditional norms. The economic benefits to the local people exceeded the rehabilitation cost over the 7-yr life of the project. There were significant on-site environmental benefits in terms of improvements in soil fertility, biodiversity, protective cover, and carbon sequestration, and off-site benefits from more productive use of labor, reduced pressure on protected areas, and the introduction of rare and threatened medicinal species onto private farmland.

R. K. Maikhuri

2002-01-01

72

Fuelwood consumption pattern at different altitudes in Garhwal Himalaya  

International Nuclear Information System (INIS)

We analyse firewood consumption along altitudinal gradient by households according to their socio-economic conditions in Garhwal Himalaya. Consumption of fuelwood was 789, 664, 518, and 544 kg/cap-yr and energy consumption for fuelwood collection was 41, 53, 52 and 80 x 103 kg/cap-yr, respectively, above 2000, for 1500-2000, 1000-1500, and 500-1000 m. Commercial fuel consumption constituted 0.6-4.5%. (author)

73

Electrical resistivity imaging of seismically active frontal Himalaya  

International Nuclear Information System (INIS)

Complete text of publication follows. Given the sensitivity of resistivity to rheology, magnetotelluric measurement are undertaken to study deep crustal electrical structures and their possible linkage to the space-depth distribution of seismicity. Magnetotelluric investigations at Thirty three sites along Bijnaur-Mallari profile cutting across major litho tectonic units of Himalaya starting from Indo Ganges plain, Siwalik, Lesser, Higher Himalaya to Tethys Himalaya. Observing the low solar activity during the survey period each site was occupied for five days. Longer occupancy allowed estimation of impedance tensor at periods greater than 500 sec at most of the stations. However at few stations electric field recordings were very noisy perhaps due to unbalanced power network of the region. This is reflected in larger error bars in estimated impedance tensors. Skewness and other dimensionality parameter indicate the validity of 2-D regional model. Robust impedance decomposition for the period band of 10 Hz- 1000 sec of eleven stations reveal that EM strike coincides with the geologic fabric. Considering regional strike EM field were decoupled in TE, TM mode and then inverted for frequency dependent conductivity distribution along the profile. The most conspicuous feature of the inverted resistivity section is the low resistivity zone at a shallow depth of 10 km beneath the Indo-Gangetic Plains that dips down at a low-angle and extends as a continuous plane right up to the northern limit of the profile. The geometry of this layer is correlated with the basement thrust separating the top of the under thrusting Indian Plate from the over-riding sedimentary wedge of lesser Himalaya. The paper will discuss the tectonic and rheological significance of the results of resistivity imaging using magnetotelluric method along the profile from Bijnaur to Mallari.

74

Six hitherto unreported Basidiomycetic macrofungi from Kashmir Himalayas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pala SA, Wani AH, Bhat MY. 2011. Six hitherto unreported Basidiomycetic macrofungi from Kashmir Himalayas. Nusantara Bioscience 3: 92-97. The Kashmir valley located in the north extreme of the India lies between 33020’ and 34054’ N latitude and 730 55’ and 75035’ E longitude. The forests constituting more than 20% of the geographical area harbors diverse macrofungal species due to their wide variability in climate altitude and nature of species constituting them. The mushroom flora of...

MOHMAD YAQUB BHAT; ABDUL HAMID WANI; SHAUKET AHMED PALA

2011-01-01

75

Dot Com Mantra: Social computing in the Central Himalayas  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Billions of dollars are being spent nationally and globally on providing computing access to digitally disadvantaged groups and cultures with an expectation that computers and the Internet can lead to higher socio-economic mobility. This ethnographic study of social computing in the Central Himalayas, India, investigates alternative social practices with new technologies and media amongst a population that is for the most part undocumented. In doing so, this book offers fresh and critical per...

Arora, P. A.

2010-01-01

76

Treeline dynamics with climate change at the central Nepal Himalaya  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Treeline shifting in tandem with climate change has widely been reported from various parts of the world. In Nepal, several impacts of climate change on the physical environment have been observed, but study on the biological impacts is lacking. This dendrochronological study was carried out at the treeline in the high mountain slope of Kalchuman Lake (3750–4003 m a.s.l.) area of Manaslu Conservation Area in the central Nepal Himalaya to explore the impact of climate chang...

Gaire, N. P.; Koirala, M.; Bhuju, D. R.; Borgaonkar, H. P.

2014-01-01

77

Radon as an earthquake precursor in NW Himalayas, India  

Science.gov (United States)

The continuous soil gas radon and daily monitoring of radon concentration in water is carried out at Amritsar (Punjab), Kangra and Chamba Valleys of NW Himalayas India to study the correlation of radon anomalies in relation to seismic activities in the region. In this study, radon monitoring in soil was carried out by using barasol probe manufactured by Algade France whereas the radon content in water was recorded using RAD7 radon monitoring system of Durridge Company USA. The radon anomalies observed in the region have been correlated with the seismic events of M ? 2 recorded in NW Himalayas by Wadia Institute of Himalayas Geology Dehradoon and Indian Meteorological Department, New Delhi. The effect of meteorological parameters viz. temperature, pressure, wind velocity and rainfall on radon emission has been studied. The correlation coefficient between radon and meteorological parameters has been evaluated. The equation for the correction of these correlations to obtain a corrected radon concentration that shows less variability is derived. Empirical equations between earthquake magnitude, epicentral distance and precursor time have been examined and respective constants were determined

Kumar, Arvind; Singh, Surinder; Singh Bajwa, Bikramjit; Mahajan, Sandeep; Dhar, Sunil; Walia, Vivek

2010-05-01

78

Selective activation of the M1 muscarinic acetylcholine receptor achieved by allosteric potentiation.  

Science.gov (United States)

The forebrain cholinergic system promotes higher brain function in part by signaling through the M(1) muscarinic acetylcholine receptor (mAChR). During Alzheimer's disease (AD), these cholinergic neurons degenerate, therefore selectively activating M(1) receptors could improve cognitive function in these patients while avoiding unwanted peripheral responses associated with non-selective muscarinic agonists. We describe here benzyl quinolone carboxylic acid (BQCA), a highly selective allosteric potentiator of the M(1) mAChR. BQCA reduces the concentration of ACh required to activate M(1) up to 129-fold with an inflection point value of 845 nM. No potentiation, agonism, or antagonism activity on other mAChRs is observed up to 100 microM. Furthermore studies in M(1)(-/-) mice demonstrates that BQCA requires M(1) to promote inositol phosphate turnover in primary neurons and to increase c-fos and arc RNA expression and ERK phosphorylation in the brain. Radioligand-binding assays, molecular modeling, and site-directed mutagenesis experiments indicate that BQCA acts at an allosteric site involving residues Y179 and W400. BQCA reverses scopolamine-induced memory deficits in contextual fear conditioning, increases blood flow to the cerebral cortex, and increases wakefulness while reducing delta sleep. In contrast to M(1) allosteric agonists, which do not improve memory in scopolamine-challenged mice in contextual fear conditioning, BQCA induces beta-arrestin recruitment to M(1), suggesting a role for this signal transduction mechanism in the cholinergic modulation of memory. In summary, BQCA exploits an allosteric potentiation mechanism to provide selectivity for the M(1) receptor and represents a promising therapeutic strategy for cognitive disorders. PMID:19717450

Ma, Lei; Seager, Matthew A; Seager, Matthew; Wittmann, Marion; Jacobson, Marlene; Bickel, Denise; Burno, Maryann; Jones, Keith; Graufelds, Valerie Kuzmick; Xu, Guangping; Pearson, Michelle; McCampbell, Alexander; Gaspar, Renee; Shughrue, Paul; Danziger, Andrew; Regan, Christopher; Flick, Rose; Pascarella, Danette; Garson, Susan; Doran, Scott; Kreatsoulas, Constantine; Veng, Lone; Lindsley, Craig W; Shipe, William; Kuduk, Scott; Sur, Cyrille; Kinney, Gene; Seabrook, Guy R; Ray, William J

2009-09-15

79

EVALUATION OF ANTIMICROBIAL PROPERTIES OF TERRESTRIAL ORCHIDS (COLLECTED FROM NORTHERN HIMALAYAS AGAINST CERTAIN HUMAN PATHOGENS  

Directory of Open Access Journals (Sweden)

Full Text Available The four main varieties of orchids, collected from northern Himalayas (Tara devi and Chhrabra forests, Shimla, HP were evaluated for their antimicrobial activity against human pathogenic bacteria. The ethanol and methanol extracts of Cypripedium cordigerum and Malaxis acuminata were found to be highly active against both P.aeruginosa and S.aureus with minimal microbial static concentration (MIC in the range of 100mg/ml. These plants particularly demonstrated antimicrobial properties against Gram negative bacterial strains, which are responsible for severe opportunistic bacterial infection and are resistant to hospitalized infections. These orchid species may thus, be considered important tools in antibacterial strategies. It can be concluded that orchid family represent an untapped source of potentially useful antibacterial products and are worthy of further study.

Amit Bharal*, Manila Kashyap, Vipan Kumar Sohpal and Jaspreet Kaur Sembi

2014-05-01

80

Radon variation in drinking water with different lithotectonic units of Uttaranchal Himalaya  

International Nuclear Information System (INIS)

The water samples from Kumaun and Garhwal Himalayas were taken from the sources used directly for the drinking purpose. In all 81 measurements of radon (222Rn) in drinking water were made. Some of the values were found higher than the maximum contamination level (MCL) of 11.1 Bq.1-1 set by US environmental radiation protection. The data were collected from different lithotectonic units along and across the various regional thrust planes, faults, shears etc. The observed values were than correlated with the geological formations and structure of the area. An effort was made for the mathematical interrelationship among the mean radon values from different lithological group. This study is also helpful for identifying regions having a strong potential of radon exposure. (author)

 
 
 
 
81

Potentially conflicting selective forces that shape the vls antigenic variation system in Borrelia burgdorferi.  

Science.gov (United States)

Changing environmental conditions present an evolutionary challenge for all organisms. The environment of microbial pathogens, including the adaptive immune responses of the infected host, changes rapidly and is lethal to the pathogen lineages that cannot quickly adapt. The dynamic immune environment creates strong selective pressures favoring microbial pathogen lineages with antigenic variation systems that maximize the antigenic divergence among expressed antigenic variants. However, divergence among expressed antigens may be constrained by other molecular features such as the efficient expression of functional proteins. We computationally examined potential conflicting selection pressures on antigenic variation systems using the vls antigenic variation system in Borrelia burgdorferi as a model system. The vls system alters the sequence of the expressed antigen by recombining gene fragments from unexpressed but divergent 'cassettes' into the expression site, vlsE. The in silico analysis of natural and altered cassettes from seven lineages in the B. burgdorferi sensu lato species complex revealed that sites that are polymorphic among unexpressed cassettes, as well as the insertion/deletion mutations, are organized to maximize divergence among the expressed antigens within the constraints of translational ability and high translational efficiency. This study provides empirical evidence that conflicting selection pressures on antigenic variation systems can limit the potential antigenic divergence in order to maintain proper molecular function. PMID:24837669

Zhou, Wei; Brisson, Dustin

2014-10-01

82

Two species of bryoria (lichenized ascomycota, parmeliaceae) from the sino-himalayas.  

Science.gov (United States)

We performed a taxonomic study on two species of the genus Bryoria from the Sino-Himalayas, SW-China. B. nadvornikiana is new to China and B. furcellata is new to Yunnan and Sichuan provinces in the Sino-Himalayas. Morphology, habitat, distributions and chemistry of the two species are discussed. PMID:24049496

Wang, Li-Song; Harada, Hiroshi; Koh, Young Jin; Hur, Jae-Seoun

2005-12-01

83

Acoustic Noise Alters Selective Attention Processes as Indicated by Direct Current (DC) Brain Potential Changes.  

Science.gov (United States)

Acoustic environmental noise, even of low to moderate intensity, is known to adversely affect information processing in animals and humans via attention mechanisms. In particular, facilitation and inhibition of information processing are basic functions of selective attention. Such mechanisms can be investigated by analyzing brain potentials under conditions of externally directed attention (intake of environmental information) versus internally directed attention (rejection of environmental stimuli and focusing on memory/planning processes). This study investigated brain direct current (DC) potential shifts-which are discussed to represent different states of cortical activation-of tasks that require intake and rejection of environmental information under noise. It was hypothesized that without background noise rejection tasks would show more positive DC potential changes compared to intake tasks and that under noise both kinds of tasks would show positive DC shifts as an expression of cortical inhibition caused by noise. DC potential shifts during intake and rejection tasks were analyzed at 16 standard locations in 45 persons during irrelevant speech or white noise vs. control condition. Without noise, rejection tasks were associated with more positive DC potential changes compared to intake tasks. During background noise, however, this difference disappeared and both kinds of tasks led to positive DC shifts. Results suggest-besides some limitations-that noise modulates selective attention mechanisms by switching to an environmental information processing and noise rejection mode, which could represent a suggested "attention shift". Implications for fMRI studies as well as for public health in learning and performance environments including susceptible persons are discussed. PMID:25264675

Trimmel, Karin; Schätzer, Julia; Trimmel, Michael

2014-01-01

84

Acoustic Noise Alters Selective Attention Processes as Indicated by Direct Current (DC Brain Potential Changes  

Directory of Open Access Journals (Sweden)

Full Text Available Acoustic environmental noise, even of low to moderate intensity, is known to adversely affect information processing in animals and humans via attention mechanisms. In particular, facilitation and inhibition of information processing are basic functions of selective attention. Such mechanisms can be investigated by analyzing brain potentials under conditions of externally directed attention (intake of environmental information versus internally directed attention (rejection of environmental stimuli and focusing on memory/planning processes. This study investigated brain direct current (DC potential shifts—which are discussed to represent different states of cortical activation—of tasks that require intake and rejection of environmental information under noise. It was hypothesized that without background noise rejection tasks would show more positive DC potential changes compared to intake tasks and that under noise both kinds of tasks would show positive DC shifts as an expression of cortical inhibition caused by noise. DC potential shifts during intake and rejection tasks were analyzed at 16 standard locations in 45 persons during irrelevant speech or white noise vs. control condition. Without noise, rejection tasks were associated with more positive DC potential changes compared to intake tasks. During background noise, however, this difference disappeared and both kinds of tasks led to positive DC shifts. Results suggest—besides some limitations—that noise modulates selective attention mechanisms by switching to an environmental information processing and noise rejection mode, which could represent a suggested “attention shift”. Implications for fMRI studies as well as for public health in learning and performance environments including susceptible persons are discussed.

Karin Trimmel

2014-09-01

85

Potentiation of tumor response to radiation or chemoradiation by selective cyclooxygenase-2 enzyme inhibitors  

International Nuclear Information System (INIS)

Cyclooxygenase-2 (COX-2) is an enzyme expressed primarily in pathologic states, such as inflammatory disorders and cancer, where it mediates prostaglandin production. Its overexpression is associated with more aggressive biologic tumor behavior and adverse patient outcome. Increasing evidence shows that agents that selectively inhibit COX-2 enhance tumor response to radiation or chemotherapeutic agents. This article gives an overview of some of this evidence. In addition, we describe new results showing that celecoxib, a selective COX-2 inhibitor, enhanced response of A431 human tumor xenografts in nude mice to radiation by an enhancement factor (EF) of 1.43 and to the chemotherapeutic agent docetaxel by an EF of 2.07. Celecoxib also enhanced tumor response when added to the combined docetaxel plus radiation treatment (EF = 2.13). Further experiments showed that selective COX-2 inhibitors enhanced tumor cell sensitivity to ionizing radiation, involving inhibition of cellular repair from radiation damage and cell cycle redistribution as mechanisms for some cell types. The results show that selective COX-2 inhibitors have the potential to improve tumor radiotherapy or radiochemotherapy, and this therapeutic strategy is currently under clinical testing

86

The therapeutic potential of class I selective histone deacetylase inhibitors in ovarian cancer  

Directory of Open Access Journals (Sweden)

Full Text Available Epithelial ovarian cancer remains the deadliest gynecologic malignancy. Despite advances in treatment, new approaches are needed. Histone deacetylases (HDACs are a family of enzymes that regulate gene expression by removing acetyl groups from lysine residues on histones and non-histone proteins. Inhibition of HDACs with small molecules has led to the development of HDAC inhibitors (HDACi that are in clinical use, primarily for hematologic malignancies. Although clinical trials with HDACi as single agents in solid tumors have been disappointing, data from independent labs and recent work by our group show that class I selective HDACi have potent anti-tumor effects in preclinical models of ovarian cancer. This review summarizes the role of HDACs in ovarian cancer and the potential niche for selective class I HDACi, particularly HDAC3 in ovarian cancer therapy.

DineoKhabele

2014-05-01

87

Active prey selection in two pelagic copepods feeding on potentially toxic and non-toxic dinoflagellates  

DEFF Research Database (Denmark)

Grazing on two red tide dinoflagellates, the potentially toxic Karenia mikimotoi and the non-toxic Gyrodinium instriatum, was examined in two species of marine copepods, Pseudocalanus elongatus and Temora longicornis. Both copepods cleared K. mikimotoi at rates that were a little lower but comparable to those at which they cleared the slightly larger G. instriatum when the two dinoflagellates were offered separately. However, when feeding on mixtures of the two prey species, the clearance rates on K. mikimotoi were substantially reduced in both copepods while their clearances of G. instiatum remained unaltered, suggesting active prey selection. Video observations of individual prey capture and feeding events showed prey rejection frequencies (caught and then released cells) that did not differ between mixed and mono-specific diets. This suggests that the selection between prey cells occurs prior to capture and that it is based on remote characterization of the cells.

Schultz, Mette; KiØrboe, Thomas

2009-01-01

88

Antimycotic potential of Crataeva religiosa Hook and Forst against some selected fungal pathogens.  

Science.gov (United States)

Crataeva religiosa Hook and Forst belonging to family Capparidaceae (Cappaceae) was selected based on its ethnopharmacological uses like diuretic, laxative, lithonotriptic, antirheumatic, antiperiodic, bitter tonic, rubifacient and counterirritant and was investigated to evaluate in vitro antimycotic potential of petroleum ether, chloroform, ethanolic and aqueous extracts against Candida albicans, Candida tropicalis, Candida krusei, Cryptococcus marinus and Aspergillus niger by disc diffusion method. The minimum inhibitory concentrations of C. religiosa extracts were found in the range of 0.062 - 0.5 mg/disc. The ethanolic extract significantly inhibits the growth of selected fungal pathogens, whereas aqueous extract do not show zone of inhibition against the tested Candida species. The results indicate the possible therapeutic uses of the plant as a potent antifungal agent. PMID:18666433

Sahoo, Sabuj; Mishra, Sagar K; Panda, Prasana K; Tripathy, Shyamlendu; Mishra, Satya R; Ellaiah, Poluri; Dash, Sashi K

2008-01-01

89

Potential benefits of genomic selection on genetic gain of small ruminant breeding programs.  

Science.gov (United States)

In conventional small ruminant breeding programs, only pedigree and phenotype records are used to make selection decisions but prospects of including genomic information are now under consideration. The objective of this study was to assess the potential benefits of genomic selection on the genetic gain in French sheep and goat breeding designs of today. Traditional and genomic scenarios were modeled with deterministic methods for 3 breeding programs. The models included decisional variables related to male selection candidates, progeny testing capacity, and economic weights that were optimized to maximize annual genetic gain (AGG) of i) a meat sheep breeding program that improved a meat trait of heritability (h(2)) = 0.30 and a maternal trait of h(2) = 0.09 and ii) dairy sheep and goat breeding programs that improved a milk trait of h(2) = 0.30. Values of ±0.20 of genetic correlation between meat and maternal traits were considered to study their effects on AGG. The Bulmer effect was accounted for and the results presented here are the averages of AGG after 10 generations of selection. Results showed that current traditional breeding programs provide an AGG of 0.095 genetic standard deviation (?a) for meat and 0.061 ?a for maternal trait in meat breed and 0.147 ?a and 0.120 ?a in sheep and goat dairy breeds, respectively. By optimizing decisional variables, the AGG with traditional selection methods increased to 0.139 ?a for meat and 0.096 ?a for maternal traits in meat breeding programs and to 0.174 ?a and 0.183 ?a in dairy sheep and goat breeding programs, respectively. With a medium-sized reference population (nref) of 2,000 individuals, the best genomic scenarios gave an AGG that was 17.9% greater than with traditional selection methods with optimized values of decisional variables for combined meat and maternal traits in meat sheep, 51.7% in dairy sheep, and 26.2% in dairy goats. The superiority of genomic schemes increased with the size of the reference population and genomic selection gave the best results when nref > 1,000 individuals for dairy breeds and nref > 2,000 individuals for meat breed. Genetic correlation between meat and maternal traits had a large impact on the genetic gain of both traits. Changes in AGG due to correlation were greatest for low heritable maternal traits. As a general rule, AGG was increased both by optimizing selection designs and including genomic information. PMID:23736059

Shumbusho, F; Raoul, J; Astruc, J M; Palhiere, I; Elsen, J M

2013-08-01

90

Growth and Yield Potential of Nine Selected Genotypes of Sweet Potato  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The growth and yield potential of nine selected genotypes of sweet potato was studied. Length and weight of vines per plant, number of main stems per plant, number and weight of tubers per plant and weight, length, diameter and dry matter content of tuber varied significantly among the genotypes. The genotypes SP3 gave the highest yield 47.59 t ha -1 followed by SP4 (42.82 t ha -1), SP16 (36.15 t ha -1) and SP1 (35.89 t ha &...

Islam, M. J.; Haque, M. Z.; Majumder, U. K.; Haque, M. M.; Hossain, M. F.

2002-01-01

91

Applied potential and radiotracer studies on poly(vinyl chloride) matrix ion-selective electrode membranes.  

Science.gov (United States)

This paper reports the effect of applied potentials on PVC matrix membranes containing (i) the barium ion-sensitive barium-Antarox C0880 complex and 2-nitrophenyl phenyl ether solvent mediator, and (ii) the calcium ion-sensitive Orion 92-20-02 phosphate-based calcium liquid ion-exchanger. Platinum electrodes were placed in solutions on each side of the membranes. The barium ion-sensitive membranes are unable to maintain stable current flows but the calcium ion-sensitive membranes are characterized by stable current flows over prolonged periods even after successive polarity reversals. Results are presented, from radiotracer experiments for permeation of ions through the membranes with and without an applied potential. No evidence was found for significant permeation of barium-133 ions through the barium ion-sensing membranes into an initially inactive solution, but it was found that barium-133 ions were incorporated into the membranes after removal of the applied potential. Permeation of sodium-22 ions through the calcium ion-sensing membranes occurred only to a limited extent in the presence of an applied potential and not at all in its absence, confirming electrode selectivity trends for calcium and sodium. Calcium-45 ions did not permeate the calcium ion-sensing membranes into an inactive counter-solution against the potential gradient, but on reversal of the polarity, permeation occurred to a far greater extent than in the absence of an applied potential. These differences in behaviour are compatible with the more complicated membrane pathways of the barium ion-sensing membranes, imposed by the complexing of barium ions by the ethyleneoxy units of Antarox C0880 in a tight helical conformation. The calcium ion-sensing membranes are much less constrained, thus permitting more facile replacement of the calcium ions in the membrane by ions from solution. PMID:18963193

Doyle, B; Moody, G J; Thomas, J D

1982-07-01

92

Winter wheat hull (husk) is a valuable source for tricin, a potential selective cytotoxic agent.  

Science.gov (United States)

The flavone, tricin (5,7,4'-trihydroxy-3',5'-dimethoxyflavone) has great potential as an anticancer agent, due to its specific chemopreventive activity. In spite of these characteristics, its use in preclinical studies is still limited, mainly because of its limited availability and high production cost. Tricin is found mainly in cereal grains, such as wheat, rice, barley, oat and maize. However, its concentration in these plants is not sufficient for commercial use. To find a reliable, rich source of tricin, we investigated its distribution in different parts of wheat (Triticum aestivum) and designed an efficient method for its isolation and purification. The highest amount (770 ± 157 mg/kg dry weight) was found in the husks of winter wheat. This concentration is one of the highest in any plant species and is considered as a cheap source of natural tricin. The purified wheat husks tricin was found to be a selective potent inhibitor of two cancer cell lines of liver and pancreas, while having no side effects on normal cells. This selective action suggests that tricin could be considered as a potential candidate for pre-clinical trials as a chemopreventive agent. In addition, fibre-rich crude wheat husk could be used as a natural chemopreventive agent in food supplement. PMID:23411198

Moheb, Amira; Grondin, Melanie; Ibrahim, Ragai K; Roy, René; Sarhan, Fathey

2013-06-01

93

GABAA receptor alpha2/alpha3 subtype-selective modulators as potential nonsedating anxiolytics.  

Science.gov (United States)

Nonselective benzodiazepines exert their pharmacological effects via GABAA receptors containing either an alpha1, alpha2, alpha3, or alpha5 subunit. The use of subtype-selective tool compounds along with transgenic mice has formed the conceptual framework for defining the requirements of subtype-selective compounds with potentially novel pharmacological profiles. More specifically, compounds which allosterically modulate the alpha2 and/or alpha3 subtypes but are devoid of, or have much reduced, effects at the alpha1 subtype are hypothesized to be anxioselective (i.e., anxiolytic but devoid of sedation). Accordingly, three compounds, MRK-409, TPA023 and TPA023B, which selectively potentiated the effects of GABA at the alpha2 and alpha3 compared to alpha1 subtypes were progressed into man. All three compounds behaved as nonsedating anxiolytics in preclinical (rodent and primate) species but, surprisingly, MRK-409 produced sedation in man at relatively low levels of occupancy ( 50%). The anxiolytic efficacy of TPA023 was evaluated in Generalized Anxiety Disorder and although these clinical trials were terminated early due to preclinical toxicity issues, the combined data from these incomplete studies demonstrated an anxiolytic-like effect of TPA023. This compound also showed a trend to increase cognitive performance in a small group of schizophrenic subjects and is currently under further evaluation of its cognition-enhancing effects in schizophrenia as part of the TURNS initiative. In contrast, the fate of the back-up clinical candidate TPA023B has not been publicly disclosed. At the very least, these data indicate that the pharmacological profile of compounds that differentially modulate specific populations of GABAA receptors is distinct from classical benzodiazepines and should encourage further preclinical and clinical investigation of such compounds, with the caveat that, as exemplified by MRK-409, the preclinical profile might not necessarily translate into man. PMID:21309116

Atack, John R

2010-01-01

94

Glacier Fluctuations in the Nanga Parbat Region of Western Himalaya  

Science.gov (United States)

Glaciers in many mountain environments have shown general retreat patterns, most likely due to atmospheric warming. Glaciers in the Western Himalaya are perhaps more complicated than other regions due to their complex topography, extensive supraglacial debris cover, and climate-system coupling involving the westerlies and the monsoon. Consequently, our objectives were to assess glacier fluctuations in the Nanga Parbat Himalaya as a part of the International Global Land Ice Measurements from Space (GLIMS) project. Specifically, we conducted change-detection studies to estimate fluctuation rates. A high-quality topographic map from 1934, Keyhole imagery from the 1970s, SPOT images from 1990 and 2005, and ASTER satellite imagery from 2004 were utilized to identify terminus positions, and triangulation methods were used to account for variations in terminus shape and orientation. Our results indicate that some glaciers are retreating and/or maintaining their frontal position while others have advanced at different time periods. Some of these glaciers have also shown downwasting characteristics in the form of increased frequency and size of supraglacial lakes. Average retreat rates, however, are not nearly as large as those reported in India, the Eastern Himalaya, and the Hindu Kush region. Glacier advances in this region have neither been reported as surge-type glaciers in the past, nor have any shown surge-type patterns; therefore, these advances may be due to positive mass balance. Analysis of climate reanalysis data (ERA40) suggest an increase in precipitation in the region. Nanga Parbat glaciers appear to be oscillating, although a recent retreat pattern can be found. There is an urgent need for regional climate and surface energy-budget modeling to assess these complexities to determine the nature of these oscillations.

Haritashya, U. K.; Bishop, M. P.; Shroder, J. F.

2008-12-01

95

Mass, charge, and energy separation by selective acceleration with a traveling potential hill  

International Nuclear Information System (INIS)

A traveling electric potential hill has been used to generate an ion beam with an energy distribution that is mass dependent from a monoenergetic ion beam of mixed masses. This effect can be utilized as a novel method for mass separation applied to identification or enrichment of ions (elements, isotopes, or molecules). This theory for mass-selective acceleration is presented here and is shown to be confirmed by experiment and by a time-dependent particle-in-cell computer simulation. Results show that monoenergetic ions with the particular mass of choice are accelerated by controlling the hill potential and the hill velocity. The hill velocity is typically 20-30% faster than the ions to be accelerated. The ability of the hill to pickup a particular mass uses the fact that small kinetic energy differences in the lab frame appear much larger in the moving hill frame. Ions will gain energy from the approaching hill if their relative energy in the moving hill frame is less than the peak potential of the hill. The final energy of these accelerated ions can be several times the source energy, which facilitates energy filtering for mass purification or identification. If the hill potential is chosen to accelerate multiple masses, the heaviest mass will have the greatest final energy. Hence, choosing the appropriate hill potential and collector retarding voltage will isolate ions with the lightest, heaviest, or intermediate mass. In the experimental device, called a Solitron,he experimental device, called a Solitron, purified 20Ne and 22Ne are extracted from a ribbon beam of neon that is originally composed of 20Ne:22Ne in the natural ratio of 91:9. The isotopic content of the processed beam is determined by measuring the energy distribution of the detected current. These results agree with the theory. In addition to mass selectivity, our theory can also be applied to the filtration of an ion beam according to charge state or energy. The Solitron is envisioned to have broad applications

96

Incipient graben formation in the NW Himalaya (Himachal Pradesh, India)  

Science.gov (United States)

GPS data and regional geological compilations show that the highest sectors of the Higher Himalaya are currently undergoing extension. This has been mainly explained with radial extension along the curvature of the Himalayan arc. However, close inspection of neotectonic extension phenomena using high-resolution satellite imagery from the upper Sutlej Valley of the NW Himalaya (Himachal Pradesh, India) suggests that the recent extension direction is rather oriented E-W, and that N-S graben-bounding normal faults in southern Tibet may propagate southward. This assessment is further corroborated by our new detailed structural field investigations and fault kinematic analysis. Our studies reveal that these normal faults cut all previously generated structures, documenting the recent activity of this fault generation. The average offset of these N-S striking, steeply dipping normal faults is in the cm to dm range for a single fault plane. However, since these brittle faults are part of a densely spaced network, the cumulative offset must be significant. Fault kinematic analysis of slickensides demonstrates that these structures are an integral part of a N-S oriented zone of diffuse E-W extension between the Leo Pargil gneiss dome in the north and the Garhwal Himalaya in the south. This E-W extension is also compatible with the orientation of T-axes of earthquake focal mechanisms obtained in the same region. Although different data sets document ongoing E-W extension, the reason for this phenomenon is not well understood. Despite the fact that some of the normal faults cut Quaternary and Tertiary units, and earthquakes occur within the realm of the extensional Leo Pargil gneiss dome, the ubiquitous occurrence of these structures within the Higher Himalaya suggests an orogen-wide origin, independent of extensional processes associated with dome formation. Alternatively, we therefore interpret the neotectonic extensional evolution of this region to reflect a very early state of a graben system propagating southward that is influenced by the E-W tensional stress regime that governs the southern Tibetan Plateau.

Hintersberger, E.; Strecker, M. R.

2007-12-01

97

Selective uptake of porphyrins within experimental atheromatous plaques: Potential for laser photodynamic therapy  

International Nuclear Information System (INIS)

The authors investigated the selective uptake of various porphyrins atheromatous plaques. Grass and microscopic examination of atherosclorotic rabbit aortas under ultraviolet light 48 hours after porphyrin administration disclosed porphyrin fluorescence exclusively on the plaques. As judged from the fluorescence emission, the order of affinity of the porphyrins for plaque is as follows: photofrin II (PF II) > hematoporphyrin derivative (HPD) > tetrasulfonatophenyl porphyrin (TPPS) ? hydroxyethylvinyldeuteroporphyrin (HVD), hematoporphyrin (HP). The potential application of intravascular irradiation of plaques labeled with porphyrins in the treatment of atheroma can be investigated using the animal model. Matching the irradiation light wave length to the porphyrin absorption peak allows specific effects to be directed to the plaque without damaging the normal vessel wall

98

Growth and Yield Potential of Nine Selected Genotypes of Sweet Potato  

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Full Text Available The growth and yield potential of nine selected genotypes of sweet potato was studied. Length and weight of vines per plant, number of main stems per plant, number and weight of tubers per plant and weight, length, diameter and dry matter content of tuber varied significantly among the genotypes. The genotypes SP3 gave the highest yield 47.59 t ha -1 followed by SP4 (42.82 t ha -1, SP16 (36.15 t ha -1 and SP1 (35.89 t ha -1. Tuber yield had significant and positive correlation with length and weight of vines per plant, number and weight of tubers per plant, average weight of tuber and diameter of tuber. Considering the associations into direct and indirect effects, weight of tubers per plant followed by average weight of tuber and number of tubers per plant found to contribute to the higher yield.

M. J. Islam

2002-01-01

99

Potential of Radiotelescopes for Atmospheric Line Observations: I. Observation Principles and Transmission Curves for Selected Sites  

CERN Document Server

Existing and planned radiotelescopes working in the millimetre (mm) and sub-millimetre wavelengths range provide the possibility to be used for atmospheric line observations. To scrutinize this potential, we outline the differences and similarities in technical equipment and observing techniques between ground-based aeronomy mm-wave radiometers and radiotelescopes. Comprehensive tables summarizing the technical characteristics of existing and future (sub)-mm radiotelescopes are given. The advantages and disadvantages using radiotelescopes for atmospheric line observations are discussed. In view of the importance of exploring the sub-mm and far-infrared wavelengths range for astronomical observations and atmospheric sciences, we present model calculations of the atmospheric transmission for selected telescope sites (DOME-C/Antarctica, ALMA/Chajnantor, JCMT and CSO on Mauna Kea/Hawaii, KOSMA/Swiss Alpes) for frequencies between 0 and 2000 GHz (0 to 150 micron) and typical atmospheric conditions using the forwar...

Schneider, Nicola; Baron, Philippe

2009-01-01

100

Characterization of N200 and P300: Selected Studies of the Event-Related Potential  

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Full Text Available The Event-Related Potential (ERP is a time-locked measure of electrical activity of the cerebral surface representing a distinct phase of cortical processing. Two components of the ERP which bear special importance to stimulus evaluation, selective attention, and conscious discrimination in humans are the P300 positivity and N200 negativity, appearing 300 ms and 200 ms post-stimulus, respectively. With the rapid proliferation of high-density EEG methods, and interdisciplinary interest in its application as a prognostic, diagnostic, and investigative tool, an understanding of the underpinnings of P300 and N200 physiology may support its application to both the basic neuroscience and clinical medical settings. The authors present a synthesis of current understanding of these two deflections in both normal and pathological states.

2005-10-01

 
 
 
 
101

ORIGINAL ARTICLE: In-vitro Antioxidant Potential of a Herbal Preparation Containing Four Selected Medicinal Plants  

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Full Text Available Background: The therapeutic effects of several plants used in traditional medicine, are usually attributed to their antioxidant properties. Aim and objective: To evaluate the in-vitro antioxidant potential of herbal preparation a combination of four selected medicinal plants (HP-4 using different experimental models.Material and Methods: Polyphenols, flavonoids and flavonols concentrations and antioxidant activity of herbal preparation (HP-4as compared to butylated hydroxyl toluene (BHT and á- tocopherol in various experimental models were evaluated. Results: The antioxidantactivities of HP-4 were concentration dependent in different experimental models and were comparable to activities of BHT anda- tocopherol. Conclusion: Polyherbal formulation of HP-4 is better than individual plant extracts.

Preeti Padmanabhan

2012-07-01

102

Tectonic controls of transient landscapes in the Bhutan Himalaya  

Science.gov (United States)

Previous research has identified many landscapes within the Himalaya that are not easily explained by classical critical taper models of orogenic wedges. One of the most striking examples is the sharp physiographic transition between the more subdued landforms of the Lower Himalayan ranges and the Higher Himalayan ranges to the north in Nepal. This transition has been attributed to several potential causes: changes in the rheology of rocks at depth, a ramp in the basal detachment of the orogenic wedge, a blind duplex, or a north-dipping, surface-breaking thrust fault. A similar, but more subdued transition marks the northern margin of perched, low-relief landscape patches found at ca. 3000 m in Bhutan. These low-relief surfaces, characterized by bogs and thick saprolites at the surface, overlie piggyback basins within the evolving orogenic wedge, filled with hundreds of meters of colluvial and alluvial deposits. The southern boundaries of the low-relief surfaces are less regular than the physiographic transition at their northern boundaries. The surfaces occur at similar elevations but are not continuous geographically, having been dissected by a series of river systems draining southward from the crest of the range. Pronounced knickpoints have formed at the southern margins of the low-relief surfaces. Our work suggests that there is a young (Pliocene-Pleistocene) fault system coincident with the physiographic transition in Bhutan. This high-angle, north-dipping structure, the Lhuentse fault, has minor normal-sense offset and could not have been responsible for differential uplift of the rugged terrain (in the hanging wall) relative to the low-relief landscape (in the footwall). The Lhuentse fault is coincident with the back limb of a previously inferred blind duplex at depth, and thus may be associated with active deformation on a rotated horse within the duplex. This duplex may also be responsible for the creation of the low-relief landscapes to the south of the Lhuentse fault due to upstream tilting in the back limb of the antiformal rock uplift pattern. Erosion patterns modeled on the basis of newly acquired 40Ar/39Ar and (U-Th)/He thermochronometric data as well as basin-average erosion rates from detrital cosmogenic nuclide concentrations are consistent with this hypothesis. We used a landscape evolution model (CHILD) to track landscape response to an imposed antiformal rock uplift gradient produced by an active duplex at depth. Rotation associated with the back limb of such a duplex causes aggradation, surface uplift, and headward migration of knickpoints. The wedge of sediment deposited during fluvial aggradation migrates northward beyond the back limb where uplift lessens. At this position in the landscape, a subdued physiographic transition develops in the model, similar to the one observed in Bhutan. Our modeling suggests that the presence and juxtaposition of low-relief landscapes and a physiographic transition, and our observed distribution of erosion rates can be explained by a single, simple mechanism related to the growth of a blind duplex.

Adams, B. A.; Whipple, K. X.; Hodges, K. V.; Van Soest, M. C.; Heimsath, A. M.

2013-12-01

103

Environmental change and challenge in the Himalaya. A historical perspective  

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Full Text Available This overview, or retrospective, has two objectives. The first is to demonstrate how the principles of ‘mountain geoecology’ were applied in an attempt to counteract the political and socio-economic impacts of a major and misguided environmental orthodoxy-the Theory of Himalayan Environmental Degradation (henceforth to be referred to as the ‘Theory’. The second is to explore the difficulties of transferring the results of on-going scholarly mountain research into the public and political decision-making process. In this sense the paper should be regarded as a case study of the potentially serious effects of exaggerated and emotionally based responses to orthodoxies founded on assumptions and latter-day myths. A third objective, reserved for the companion paper in this issue, outlines the origins of mountain geoecology and explores how academic research influenced the inclusion of high level concern for mountain problems within AGENDA 21, one of the principal results of the 1992 UN Conference on Environment and Development (popularly known as the Rio Earth Summit and declaration of 2002 as the International Year of Mountains. The original environmental orthodoxy (the Theory has been eclipsed since the turn of the Millennium by a new populist alarm proposing that the current climate warming will cause all the Himalayan glaciers to disappear in the near future. From this it would follow that, as the glacier melt progresses, numerous large glacial lakes, forming as a consequence, would burst and the ensuing floods would annihilate many millions of people. Eventually, as the glaciers disappeared vital rivers, such as the Ganges and Brahmaputra, would wither to seasonal streams heralding further massive loss of life due to desertification and starvation. This current environmental alarm could be regarded as a present day parallel to the original Theory and will be examined in the final section of the paper. Between 1970 and about 1985 it was almost universal wisdom amongst scholars and development specialists, as well as conservationists, that the Himalaya were on the brink of environmental, and hence socio-economic and political collapse. This theme of gloom and doom was taken up avidly by journalists, politicians, and diplomats; it influenced the expenditure of large sums of aid and development money, and augmented periodic international confrontations. In concise terms, in the early 1970s an assumed approaching environmental disaster was perceived to be driven by relentless growth in the population of subsistence hill communities and their dependence on mountain forests for fuel, fodder, building materials, and conversion to agricultural land. The assumption of rapid and catastrophic deforestation of steep hillslopes under a monsoon climate (the World Bank predicted that there would be no accessible forest remaining in Nepal by the year 2000 led inexorably to a series of dependent assumptions: increasing soil erosion and worsening landslide incidence; accelerated flooding and siltation on the plains of Gangetic India and Bangladesh; social and political unrest, if not serious armed conflict – the notion of a world super-crisis, considering that the region in question contained about ten percent of the world’s entire human population and about thirty percent of its poorest. As will be emphasized later, none of this all-embracing construct was based on reliable evidence, but it was accepted world-wide as a given. It represents a prime example of the dangers associated with convenient adoption of environmental myths, or environmental orthodoxies, especially where the myth is a Western ‘scientific’ construct. I characterized it as The Theory of Himalayan Environmental Degradation (Ives, 1985.Esta perspectiva global, o retrospectiva, tiene dos objetivos. El primero es demostrar cómo se aplicaron los principios de la “geoecología de montaña” en un intento por contrarrestar los impactos políticos y socioeconómicos de una errónea ortodoxia ambiental, la Teoría de la Degr

Ives, Jack D.

2012-05-01

104

Hyperosmolar solutions selectively block action potentials in rat myelinated sensory fibers: implications for diabetic neuropathy.  

Science.gov (United States)

Diabetic neuropathy is a common complication of diabetes mellitus patients. It is a wide range of abnormalities affecting proximal and distal peripheral sensory and motor nerves. Although plasma hyperosmolality is a common finding in diabetes mellitus, the effects of hyperosmolality on conduction of various sensory signal components have not been addressed in detail. Here we show that in rat dorsal root ganglion (DRG) preparations from normal rats, hyperosmolar solutions (360 mmol/kg, containing increased glucose, sucrose, NaCl, or mannitol) produce a selective block of signal propagation in myelinated sensory A-fibers. In compound action potential (CAP) recordings with suction electrodes, peak A-fiber CAP amplitude was selectively decreased (20%), while the C-fiber peak remained intact or was slightly increased. Hyperosmolar solutions had smaller effects on conduction velocity (CV) of both A- and C-fibers (approximately 5% decrease). Hyperosmolality-induced CAP changes could not be observed during recordings from isolated spinal nerves but were evident during recordings from desheathed spinal nerves. In intracellular recordings, hyperosmolar solutions produced a block of spinal nerve-evoked action potential invasion into the somata of some A-fiber neurons. Removal of extracellular calcium completely prevented the hyperosmolality-induced CAP decreases. Based on these data, we propose that the decreased CAP amplitudes recorded in human patients and in animal models of diabetes are in part due to the effects of hyperosmolality and would depend on the extracellular osmolality at the time of sensory testing. We also hypothesize that hyperosmolality may contribute to both the sensory abnormalities (paresthesias) and the chronic pain symptoms of diabetic neuropathy. PMID:13679399

Matsuka, Yoshizo; Spigelman, Igor

2004-01-01

105

Influence of anode potentials on selection of Geobacter strains in microbial electrolysis cells.  

Science.gov (United States)

Through their ability to directly transfer electrons to electrodes, Geobacter sp. are key organisms for microbial fuel cell technology. This study presents a simple method to reproducibly select Geobacter-dominated anode biofilms from a mixed inoculum of bacteria using graphite electrodes initially poised at -0.25, -0.36 and -0.42 V vs. Ag/AgCl. The biofilms all produced maximum power density of approximately 270 m Wm(-2) (projected anode surface area). Analysis of 16S rRNA genes and intergenic spacer (ITS) sequences found that the biofilm communities were all dominated by bacteria closely related to Geobacter psychrophilus. Anodes initially poised at -0.25 V reproducibly selected biofilms that were dominated by a strain of G. psychrophilus that was genetically distinct from the strain that dominated the -0.36 and -0.42 V biofilms. This work demonstrates for the first time that closely related strains of Geobacter can have very different competitive advantages at different anode potentials. PMID:23665518

Commault, Audrey S; Lear, Gavin; Packer, Michael A; Weld, Richard J

2013-07-01

106

Soil-gas radon as seismotectonic indicator in Garhwal Himalaya.  

Science.gov (United States)

Research on earthquake-related radon monitoring has received enormous attention recently. Anomalous behaviour of radon in soil and groundwater can be used as a reliable precursor for an impending earthquake. While earthquake prediction may not yet be possible, earthquake prediction research has greatly increased our understanding of earthquake source mechanisms, the structural complexities of fault zones, and the earthquake recurrence interval, expected at a given location. This paper presents some results of continuous monitoring of radon in soil-gas in Garhwal Himalaya, India. Daily soil-gas radon monitoring with seismic activity and meteorological parameters were performed in the same laboratory system, located at H.N.B. Garhwal University Campus, Tehri Garhwal, India. Radon anomalies along with meteorological parameters were found to be statistically significant for the seismic events within the magnitudes M2.0-M6.0 and epicentral distances of 16-250 km from the monitoring station. The frequent positive and negative anomalies with constant environmental perturbation indicate the opening and closing of micro cracks within the volume of dilatancy by strain energy. The spike-like and sharp peak anomalies were recorded before, during and after earthquakes occurred in the area. The variations in radon concentrations in soil-gas are found to be correlated with seismic activities in the Garhwal Himalaya. The correlation between radon level and meteorological parameters is also discussed. PMID:18502650

Ramola, R C; Prasad, Yogesh; Prasad, Ganesh; Kumar, Sushil; Choubey, V M

2008-10-01

107

Objective selection of EEG late potentials through residual dependence estimation of independent components  

International Nuclear Information System (INIS)

This paper presents a novel method to objectively select electroencephalographic (EEG) cortical sources estimated by independent component analysis (ICA) in event-related potential (ERP) studies. A proximity measure based on mutual information is employed to estimate residual dependences of the components that are then hierarchically clustered based on these residual dependences. Next, the properties of each group of components are evaluated at each level of the hierarchical tree by two indices that aim to assess both cluster tightness and physiological reliability through a template matching process. These two indices are combined in three different approaches to bring to light the hierarchical structure of the cluster organizations. Our method is tested on a set of experiments with the purpose of enhancing late positive ERPs elicited by emotional picture stimuli. Results suggest that the best way to look for physiologically plausible late positive potential (LPP) sources is to explore in depth the tightness of those clusters that, taken together, best resemble the template. According to our results, after brain sources clustering, LPPs are always identified more accurately than from ensemble-averaged raw data. Since the late components of an ERP involve the same associative areas, regardless of the modality of stimulation or specific tasks administered, the proposed method can be simply adapted to other ERP studies, and extended from psychophysiological studies to pathological or sport training evaluation support

108

Effects of potential partners' physical attractiveness and socioeconomic status on sexuality and partner selection.  

Science.gov (United States)

Male (n = 170) and female (n = 212) college students viewed photographs, which had been prerated for physical attractiveness, of three opposite-sex individuals. These photographs were paired with three levels of occupational status and income. Subjects indicated their willingness to engage in relationships of varying levels of sexual intimacy and marital potential with the portrayed individuals. Analyses of variance, correlations, and trend analyses supported the hypotheses. Compared to men, women are more likely to prefer or insist that sexual intercourse occur in relationships that involve affection and marital potential, and women place more emphasis than men do on partners' SES in such relationships. Consequently, men's SES and their willingness and ability to invest affection and resources in relationships may often outweigh the effects of their physical attractiveness in women's actual selection of partners. These results and the literature reviewed are more consistent with parental investment theory than with the view that these sex differences are solely the result of differential access to resources and differential socialization. PMID:2337380

Townsend, J M; Levy, G D

1990-04-01

109

Assessment of Potential for Biodiesel Feedstock of Selected Wild Plant Oils Indigenous to Botswana  

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Full Text Available Biodiesel is attracting increasing attention worldwide as a blending component or a direct replacement of petroleum diesel fuel in transport sector.The challenge to scientists and engineers is to identify appropriate feedstocks for biodiesel production. The majority of potential feedstocks are edible species which are at the centre of the “fuel versus food” debate. It is therefore imperative for scientists and engineers to continue the search for biodiesel feedstocks that do not compete with food security. This work investigated some properties of selected wild plant oils to assess suitability as feedstock for biodiesel production. Properties reviewed include oil yield levels, oil acidity, percentage of free fatty acids and the level of energy content. The wild plant oils under review were extracted from Scelerocarya birrea, Tylosema esculentum and Ximenia caffra fruit seeds. In addition, Jatropha oil was analysed for purposes of comparison. Thermal properties of wild plant oils were compared with those of petroleum diesel. Results indicate that wild plant oils investigated had sufficiently high oil yield levels desirable for potential feedstocks for biodiesel production. The energy content levels of wild plant oils were marginally lower than that of petroleum diesel with a maximum variation of 5.7 MJ/Kg.

Jerekias Gandure

2011-12-01

110

A comparative study on the potential of oxygen release by roots of selected wetland plants  

Science.gov (United States)

The capacity of root oxygen release by selected wetland plants pre-grown under both nutrient solution and artificial wastewater conditions were determined. The results indicated that the significant differences of root oxygen release by the tested wetland plants existed, and the biochemical process was the main source of root oxygen release as oxygen released by Vetiveria zizanioides L. Nash roots through biochemical process was contributed to 77% and 74% of total root oxygen release under nutrient solution conditions and artificial wastewater conditions, respectively, and that was 72% and 71% of total root oxygen release for Cyperus alternifolius L. It was found that the formation of root plaque with iron oxide was a function of root oxygen release as iron oxide concentration in root plaque was positively correlated to the potential of oxygen released by wetland plant roots with the regression coefficients as 0.874 *( p zizanioides L. Nash with the highest potential of root oxygen release and higher tolerance to wastewater could be recommended to establish vegetated wetlands for treating nutrient-rich wastewater such as domestic wastewater.

Yao, Fang; Shen, Gen-xiang; Li, Xue-lian; Li, Huai-zheng; Hu, Hong; Ni, Wu-zhong

111

Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests.  

Science.gov (United States)

The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei subsp. paracasei) isolated from table olives were screened for their probiotic potential. Lb. rhamnosus GG and Lb. casei Shirota were used as reference strains. The in vitro tests included survival in simulated gastrointestinal tract conditions, antimicrobial activity (against Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7), Caco-2 surface adhesion, resistance to 9 antibiotics and haemolytic activity. Three (3) Lb. pentosus, 4 Lb. plantarum and 2 Lb. paracasei subsp. paracasei strains demonstrated the highest final population (>8 log cfu/ml) after 3 h of exposure at low pH. The majority of the tested strains were resistant to bile salts even after 4 h of exposure, while 5 Lb. plantarum and 7 Lb. pentosus strains exhibited partial bile salt hydrolase activity. None of the strains inhibited the growth of the pathogens tested. Variable efficiency to adhere to Caco-2 cells was observed. This was the same regarding strains' susceptibility towards different antibiotics. None of the strains exhibited ?-haemolytic activity. As a whole, 4 strains of Lb. pentosus, 3 strains of Lb. plantarum and 2 strains of Lb. paracasei subsp. paracasei were found to possess desirable in vitro probiotic properties similar to or even better than the reference probiotic strains Lb. casei Shirota and Lb. rhamnosus GG. These strains are good candidates for further investigation both with in vivo studies to elucidate their potential health benefits and in olive fermentation processes to assess their technological performance as novel probiotic starters. PMID:23200662

Argyri, Anthoula A; Zoumpopoulou, Georgia; Karatzas, Kimon-Andreas G; Tsakalidou, Effie; Nychas, George-John E; Panagou, Efstathios Z; Tassou, Chrysoula C

2013-04-01

112

Automated tube potential selection for standard chest and abdominal CT in follow-up patients with testicular cancer: comparison with fixed tube potential  

Energy Technology Data Exchange (ETDEWEB)

To evaluate prospectively, in patients with testicular cancer, the radiation dose-saving potential and image quality of contrast-enhanced chest and abdominal CT with automated tube potential selection. Forty consecutive patients with testicular cancer underwent contrast-enhanced arterio-venous chest and portal-venous abdominal CT with automated tube potential selection (protocol B; tube potential 80-140 kVp), which is based on the attenuation of the CT topogram. All had a first CT at 120 kVp (protocol A) using the same 64-section CT machine and similar settings. Image quality was assessed; dose information (CTDI{sub vol}) was noted. Image noise and attenuation in the liver and spleen were significantly higher for protocol B (P < 0.05 each), whereas attenuation in the deltoid and erector spinae muscles was similar. In protocol B, tube potential was reduced to 100 kVp in 18 chest and 33 abdominal examinations, and to 80 kVp in 5 abdominal CT examinations; it increased to 140 kVp in one patient. Image quality of examinations using both CT protocols was rated as diagnostic. CTDI{sub vol} was significantly lower for protocol B compared to protocol A (reduction by 12%, P < 0.01). In patients with testicular cancer, radiation dose of chest and abdominal CT can be reduced with automated tube potential selection, while image quality is preserved. (orig.)

Gnannt, Ralph; Winklehner, Anna; Frauenfelder, Thomas; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Eberli, Daniel [University Hospital Zurich, Clinic for Urology, Zurich (Switzerland); Knuth, Alexander [University Hospital Zurich, Clinic for Oncology, Zurich (Switzerland)

2012-09-15

113

A Probabilistic Estimate of the Most Perceptible Earthquake Magnitudes in the NW Himalaya and Adjoining Regions  

Science.gov (United States)

NW Himalaya and its neighboring region (25°-40°N and 65°-85°E) is one of the most seismically hazardous regions in the Indian subcontinent, a region that has historically experienced large to great damaging earthquakes. In the present study, the most perceptible earthquake magnitudes, M p, are estimated for intensity I = VII, horizontal peak ground acceleration a = 300 cm/s2 and horizontal peak ground velocity v = 10 cm/s in 28 seismogenic zones using the two earthquake recurrence models of uc(Kijko) and uc(Sellevoll )(Bulletin of the Seismological Society of America 82(1):120-134 1992 uc()) and Gumbel's third asymptotic distribution of extremes (GIII). Both methods deal with maximum magnitudes. The earthquake perceptibility is calculated by combining earthquake recurrence models with ground motion attenuation relations at a particular level of intensity, acceleration and velocity. The estimated results reveal that the values of M p for velocity v = 10 cm/s show higher estimates than corresponding values for intensity I = VII and acceleration a = 300 cm/s2. It is also observed that differences in perceptible magnitudes calculated by the Kijko-Sellevoll method and GIII statistics show significantly high values, up to 0.7, 0.6 and 1.7 for intensity, acceleration and velocity, respectively, revealing the importance of earthquake recurrence model selection. The estimated most perceptible earthquake magnitudes, M p, in the present study vary from M W 5.1 to 7.7 in the entire zone of the study area. Results of perceptible magnitudes are also represented in the form of spatial maps in 28 seismogenic zones for the aforementioned threshold levels of intensity, acceleration and velocity, estimated from two recurrence models. The spatial maps show that the Quetta of Pakistan, the Hindukush-Pamir Himalaya, the Caucasus mountain belt and the Himalayan frontal thrust belt (Kashmir-Kangra-Uttarkashi-Chamoli regions) exhibit higher values of the most perceptible earthquake magnitudes (M W > 6.0). These spatially-distributed values indicate good agreement with high seismic hazard zones in previously published hazard maps based on seismicity, maximum expected earthquake magnitudes during specific time intervals and maximum expected acceleration. These maps have useful implications in preparing earthquake selection criteria for the anti-seismic design of non-critical structures in the study region.

Yadav, R. B. S.; Koravos, G. Ch.; Tsapanos, T. M.; Vougiouka, G. E.

2014-06-01

114

Homology modelling of CB1 receptor and selection of potential inhibitor against Obesity.  

Science.gov (United States)

Obesity and patient morbidity has become a health concern worldwide. Obesity is associated with over activity of the endocannabinoid system, which is involved in the regulation of appetite, lipogenesis and insulin resistance. Hypothalamic cannabinoid-1 receptor (CB1R) inverse agonists reduce body weight and improve cardiometabolic abnormalities in experimental and human obesity but displayed neuropsychiatric side effects. Hence, there is a need to develop therapeutics which employs blocking peripheral CB1 receptors and still achieve substantial weight loss. In view of the same, adipose tissue CB1 receptors are employed for this study since it is more specific in reducing visceral fat. Computer aided structure based virtual screening finds application to screen novel inhibitors and develop highly selective and potential drug. The rational drug design requires crystal structure for the CB1 receptor. However, the structure for the CB1 receptor is not available in its native form. Thus, we modelled the crystal structure using a lipid G-Protein coupled receptor (PDB: 3V2W, chain A) as template. Furthermore, we have screened a herbal ligand Quercetin [- 2- (3, 4-dihydroxyphenyl) - 3, 5, 7-trihydroxychromen-4-one] a flavonol present in Mimosa pudica based on its better pharmacokinetics and bioavailability profile. This ligand was selected as an ideal lead molecule. The docking of quercetin with CB1 receptor showed a binding energy of -6.56 Kcal/mol with 4 hydrogen bonds, in comparison to the known drug Rimonabant. This data finds application in proposing antagonism of CB1 receptor with Quercetin, for controlling obesity. PMID:22829723

Shrinivasan, Mahesh; Skariyachan, Sinosh; Aparna, Vaka; Kolte, Vinod Rama

2012-01-01

115

Decadal to Millennial scale erosion rates in the Nepal Himalayas  

Science.gov (United States)

On a sub-millennial time scale the spatial distribution of erosion is controlled to first order by tectonics, relief, and possibly precipitation, and secondly by vegetation, lithology, temperature and human activity. The Himalayas form a very distinct orographic barrier with a pronounced rainfall gradient from the South to the North and have a very rugged terrain, causing highly dynamic surface processes and fast erosion rates. Thus, the Himalayas provide an ideal site of investigation to study erosion and constrain its controlling factors. In this contribution we present an integrated comparison of mean catchment erosion rates, calculated from in-situ produced 10Be cosmogenic isotope concentration in river sands (representative for millennial time scales) and suspended sediment measurements (integrating the annual to decadal time spans). We discuss erosion rates and patterns in the context of precipitation-landscape features of the studied catchments. The samples cover all major rivers, and several minor tributaries of the Narayani watershed (30,000 \\ km2) in central Nepal. They represent all lithologies, topographic units and climate regimes across the Himalayan range. The erosion rates, both from cosmogenic nuclide analysis and suspended sediment measurements, range from 0.1 to 4 mm/yr. These agree well between the two methods and also with already published data for the major outlet stations at the Himalayan front. However, in the Middle and High Himalayas the cosmogenic erosion rates are significantly higher than those from suspended sediment measurements. While on the short term (intra-annual) a clear relation between precipitation and erosion can be observed, the cosmogenic erosion rates show no clear dependency with the basin wide precipitation pattern. Furthermore, no relation could be observed with the dominant lithological units and the degree of glaciation. Our observations confirm the overall established relationship between erosion rates, relief and slope, showing clearly that topography exerts a predominant control on spatial erosion rates on the millennial timescale. However, we observe a different relationship between main stream basins (> 250 \\ km2) and small tributary basins (< 250 \\ km2). Small basins show in general lower erosion rates than larger basins for respectively the same topographic characteristics.

Andermann, C.; Bonnet, S.; Gloaguen, R.; Crave, A.; Merchel, S.; Braucher, R.; Bourles, D. L.

2012-12-01

116

Automated tube potential selection for standard chest and abdominal CT in follow-up patients with testicular cancer: comparison with fixed tube potential  

International Nuclear Information System (INIS)

To evaluate prospectively, in patients with testicular cancer, the radiation dose-saving potential and image quality of contrast-enhanced chest and abdominal CT with automated tube potential selection. Forty consecutive patients with testicular cancer underwent contrast-enhanced arterio-venous chest and portal-venous abdominal CT with automated tube potential selection (protocol B; tube potential 80-140 kVp), which is based on the attenuation of the CT topogram. All had a first CT at 120 kVp (protocol A) using the same 64-section CT machine and similar settings. Image quality was assessed; dose information (CTDIvol) was noted. Image noise and attenuation in the liver and spleen were significantly higher for protocol B (P vol was significantly lower for protocol B compared to protocol A (reduction by 12%, P < 0.01). In patients with testicular cancer, radiation dose of chest and abdominal CT can be reduced with automated tube potential selection, while image quality is preserved. (orig.)

117

EEG Channel Selection Using Particle Swarm Optimization for the Classification of Auditory Event-Related Potentials  

Science.gov (United States)

Brain-machine interfaces (BMI) rely on the accurate classification of event-related potentials (ERPs) and their performance greatly depends on the appropriate selection of classifier parameters and features from dense-array electroencephalography (EEG) signals. Moreover, in order to achieve a portable and more compact BMI for practical applications, it is also desirable to use a system capable of accurate classification using information from as few EEG channels as possible. In the present work, we propose a method for classifying P300 ERPs using a combination of Fisher Discriminant Analysis (FDA) and a multiobjective hybrid real-binary Particle Swarm Optimization (MHPSO) algorithm. Specifically, the algorithm searches for the set of EEG channels and classifier parameters that simultaneously maximize the classification accuracy and minimize the number of used channels. The performance of the method is assessed through offline analyses on datasets of auditory ERPs from sound discrimination experiments. The proposed method achieved a higher classification accuracy than that achieved by traditional methods while also using fewer channels. It was also found that the number of channels used for classification can be significantly reduced without greatly compromising the classification accuracy. PMID:24982944

Hokari, Haruhide

2014-01-01

118

Breeding potential of selected crosses for genetic improvement of finger millet  

Directory of Open Access Journals (Sweden)

Full Text Available Often, a plant breeder/researcher is confronted with thetask of handling segregating populations derived from alarge number of crosses. Early elimination of poor crosseshelps in efficient utilization of land, time and humanresources and allows handling of reasonably largesegregating populations derived from a few promisingcrosses. Under this premise, an investigation was carriedout at the experimental fields of University of AgriculturalSciences (UAS, GKVK campus, Bangalore, India during1998–2000 to assess the utility of general combiningability (gca of selected parents for making crosses thatare likely to result in superior recombinant inbred lines(RILs in advanced generations. Two crosses whoseparents differed for their combining ability were comparedwith the cross whose parents were similar for theircombining ability for their likely productivity in isolatingsuperior recombinant lines. The results revealed that thecrosses involving at least one of their parents with highgca effects are productive for deriving RILs with desiredtraits and desired mean expression. The mean andvariance of early segregating generation serve as usefulguidelines for predicting the breeding potential of crosses.

Jayarame Gowda

2009-12-01

119

Selection of a mineral binder with potentialities for the stabilization/solidification of aluminum metal  

Science.gov (United States)

In a strongly alkaline medium, such as that encountered in conventional cementitious materials based on Portland cement, aluminum metal is corroded, with continued production of hydrogen. In order to develop a mineral matrix having enhanced compatibility with aluminum, a literature review was first undertaken to identify binders capable of reducing the pore solution pH compared with Portland cement. An experimental study was then carried out to measure the hydrogen production resulting from corrosion of aluminum metal rods encapsulated in the different selected cement pastes. The best results were achieved with magnesium phosphate cement, which released very little hydrogen over the duration of the study. This production could be reduced still further by adding a corrosion inhibitor (lithium nitrate) to the mixing solution. Open circuit potential measurement and Electrochemical Impedance Spectroscopy of aluminum electrode encapsulated in two pastes based on Portland cement and magnesium phosphate cement showed different redox behaviors. In the Portland cement paste, the electrochemical data confirmed the corrosion of aluminum whereas this latter tended to a passive state in the magnesium phosphate binder.

Cau Dit Coumes, C.; Lambertin, D.; Lahalle, H.; Antonucci, P.; Cannes, C.; Delpech, S.

2014-10-01

120

Selective and sensitive platform for function-based screening of potentially harmful furans.  

Science.gov (United States)

Many furan-containing compounds have been reported to be toxic and/or carcinogenic. Furanoids have been found in a wide range of fruits, herbs, foods, and beverages. The risks for intake of toxic furans have been rising, due to the rapid growth of globe-wide consumption of natural products. The objective of the study was to develop an analytical platform to screen cis-enediones (cis-enedials or ?-ketoenals) resulting from metabolic activation of potentially harmful furans. 2,5-Dimethylfuran (DMF), a model furan compound, was incubated with rat liver microsomes supplemented with glutathione (GSH) and 4-bromobenzylamine (BBA) as trapping agents, to produce a GSH/BBA-derived pyrrole. The incubation mixture was monitored by acquiring neutral loss scan of 129 Da and precursor ion scans of m/z 272, 169, and 171 in polarity switch mode. Four individual chromatograms showed the respective peak with the same retention time. An additional six furan-containing compounds were tested by the same approach, and similar observation was obtained. The system also showed its extremely high sensitivity, and an estimate of the limit of detection for DMF bioactivated in rat liver microsomes was bromine-tagged pyrrole derivatives. Crude extracts obtained from traditional Chinese medicine Dioscorea bulbifera L., known to contain furanoditerpenoids, were analyzed by the approach. In conclusion, the platform has been proven selective, sensitive, effective, and reliable, and ICP MS allows us to estimate the resulting bromine-labeled pyrroles without authentic standards. PMID:25279953

Wang, Kai; Zheng, Liwei; Peng, Ying; Song, Juan-E; Zheng, Jiang

2014-11-01

 
 
 
 
121

Earthquakes of the Nepal Himalaya: Towards a physical model of the seismic cycle  

Science.gov (United States)

Documenting geodetic strain across the Nepal Himalaya with various GPS and leveling data, we show that unlike other subduction zones that exhibit a heterogeneous and patchy coupling pattern along strike, the last hundred kilometers of the Main Himalayan Thrust fault, or MHT, appear to be uniformly locked, devoid of any of the "creeping barriers" that traditionally ward off the propagation of large events. The approximately 20 mm/yr of reckoned convergence across the Himalaya matching previously established estimates of the secular deformation at the front of the arc, the slip accumulated at depth has to somehow elastically propagate all the way to the surface at some point. And yet, neither large events from the past nor currently recorded microseismicity nearly compensate for the massive moment deficit that quietly builds up under the giant mountains. Along with this large unbalanced moment deficit, the uncommonly homogeneous coupling pattern on the MHT raises the question of whether or not the locked portion of the MHT can rupture all at once in a giant earthquake. Univocally answering this question appears contingent on the still elusive estimate of the magnitude of the largest possible earthquake in the Himalaya, and requires tight constraints on local fault properties. What makes the Himalaya enigmatic also makes it the potential source of an incredible wealth of information, and we exploit some of the oddities of Himalayan seismicity in an effort to improve the understanding of earthquake physics and cipher out the properties of the MHT. Thanks to the Himalaya, the Indo-Gangetic plain is deluged each year under a tremendous amount of water during the annual summer monsoon that collects and bears down on the Indian plate enough to pull it away from the Eurasian plate slightly, temporarily relieving a small portion of the stress mounting on the MHT. As the rainwater evaporates in the dry winter season, the plate rebounds and tension is increased back on the fault. Interestingly, the mild waggle of stress induced by the monsoon rains is about the same size as that from solid-Earth tides which gently tug at the planets solid layers, but whereas changes in earthquake frequency correspond with the annually occurring monsoon, there is no such correlation with Earth tides, which oscillate back-and-forth twice a day. We therefore investigate the general response of the creeping and seismogenic parts of MHT to periodic stresses in order to link these observations to physical parameters. First, the response of the creeping part of the MHT is analyzed with a simple spring-and-slider system bearing rate-strengthening rheology, and we show that at the transition with the locked zone, where the friction becomes near velocity neutral, the response of the slip rate may be amplified at some periods, which values are analytically related to the physical parameters of the problem. Such predictions therefore hold the potential of constraining fault properties on the MHT, but still await observational counterparts to be applied, as nothing indicates that the variations of seismicity rate on the locked part of the MHT are the direct expressions of variations of the slip rate on its creeping part, and no variations of the slip rate have been singled out from the GPS measurements to this day. When shifting to the locked seismogenic part of the MHT, spring-and-slider models with rate-weakening rheology are insufficient to explain the contrasted responses of the seismicity to the periodic loads that tides and monsoon both place on the MHT. Instead, we resort to numerical simulations using the Boundary Integral CYCLes of Earthquakes algorithm and examine the response of a 2D finite fault embedded with a rate-weakening patch to harmonic stress perturbations of various periods. We show that such simulations are able to reproduce results consistent with a gradual amplification of sensitivity as the perturbing period get larger, up to a critical period corresponding to the characteristic time of evolution of the seismicity in response t

Ader, Thomas J.

122

Selection of Origanum vulgare plants for essential oil, carvacrol, total phenols and antioxidant potential  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the summer of 2005, individual plant selection was performed on different oregano populations started at Applied Plant Research (PPO-WUR) in Lelystad, The Netherlands. Selection was focused on erect growing, healthy, leafy but flowering, productive plants. Samples of these visually selected plants were analyzed for essential oil content and its main components (such as carvacrol). Some of the selected plants were also screened for phenolic components and antioxidant activity. This paper de...

Mheen, H. J. C. J.; Havkin-frenkel, D.; Berg, W.

2010-01-01

123

Variability of volatile constituents in Artemisia maritima in western Himalaya.  

Science.gov (United States)

Chemical composition of the essential oil of Artemisia maritima, collected from three different high altitude locations in western Himalaya was studied by gas-chromatography mass spectrometry. Twenty-five constituents were identified in the oil distilled from the sample from Pooh, of which 1,8-cineole (23.8%) and chrysanthenone (17.54%) were the major constituents. Twenty volatile constituents were identified from the sample collected from Rhongtong pass, of which chrysanthenone (38.1%) and 1,8-cineole (37.3%) were the major constituents. In the oil distilled from the sample collected from Lahaul-Spiti 28 constituents were identified, of which 1,8-cineole (44.22%), camphor (9.16%) and borneol (10.94%) were the major constituents. In this sample chrysanthenone was present in very low percentage. PMID:18569692

Jaitak, Vikas; Singh, Bikram; Kaul, V K

2008-05-10

124

Microbiological studies of ethnic meat products of the Eastern Himalayas.  

Science.gov (United States)

Native microorganisms from some ethnic meat products of the Eastern Himalayas such as lang kargyong, yak kargyong, faak kargyong, lang satchu, yak satchu and suka ko masu were isolated and characterized. The bacterial isolates included Lactobacillus sake, Lactobacillus curvatus, Lactobacillus divergens, Lactobacillus carnis, Lactobacillus sanfrancisco, Lactobacillus plantarum, Lactobacillus casei, Lactobacillus brevis, Enterococcus faecium, Leuconostoc mesenteroides, Pediococcus pentosaceous, Bacillus subtilis, Bacillus mycoides, Bacillus thuringiensis, Bacillus lentus and Bacillus licheniformis, Micrococcus and Staphylococcus. Yeast isolates included Debaryomyces hansenii, Debaryomyces polymorphus, Debaryomyces pseudopolymorphus, Pichia burtonii, Pichia anomala, Candida famata and the mould Rhizopus was also identified. Many of the LAB isolates demonstrated some antimicrobial activity, enzymatic activity and a few showed a high degree of hydrophobicity. None of the strains produced biogenic amines. PMID:20416835

Rai, Arun Kumar; Tamang, Jyoti Prakash; Palni, Uma

2010-07-01

125

Tectonostratigraphic subdivisions of the Himalaya: A view from the west  

Science.gov (United States)

Indian plate rocks in the central Himalaya have traditionally been divided into orogen-parallel, fault-bound tectonostratigraphic zones. A straightforward westward extrapolation of these zones has proved problematic in part because of a lack of consensus on the existence or significance of major faults within the metamorphic zone of the Indian plate in Pakistan where more than 10 locations for the Main Central thrust (MCT) have been proposed. We address this ambiguity by systematically tracing established central Himalayan tectonostratigraphy around the western Himalayan syntaxis and across Pakistan. This exercise reveals the following stratigraphic and structural relationships: (1) There is a westward decrease in Neogene shortening across the Himalayan fold and thrust belt such that there is no age equivalent thrust in Pakistan with displacement and metamorphic juxtaposition equivalent to the central Himalayan MCT. (2) Shortening across the fold and thrust belt in western Pakistan is concentrated in the unmetamorphosed foreland as opposed to the metamorphic zone in the central Himalaya. (3) Lesser Himalayan, Higher Himalayan, and Tethyan rocks are in stratigraphic order within the metamorphic zone of Pakistan which appears to be the metamorphic equivalent of Kashmir Tethyan stratigraphy. (4) The combination of early Paleozoic and late Paleozoic tectonism in Pakistan has locally eliminated Upper Proterozoic Higher Himalayan rock and lower to middle Paleozoic Tethyan rock from the metamorphic zone of Pakistan. (5) Late Cretaceous and/or early Paleocene proto-Himalayan deformation in the Pakistan foreland telescoped and eroded stratigraphy prior to the main phase of Himalayan orogeny. (6) Tectonostratigraphic zones are offset in eastern Pakistan by the transverse Jhelum-Balakot fault. (7) There is no evidence within the Indian plate of Pakistan for a large-scale normal fault system comparable to the South Tibetan detachment system. (8) Stratigraphy, as well as the age and tectonic setting of deformation and metamorphism, must be taken into account when drawing tectonostratigraphic zones.

Dipietro, Joseph A.; Pogue, Kevin R.

2004-10-01

126

Model sensitivity analysis study for western disturbances over the Himalayas  

Science.gov (United States)

Western disturbances (WDs) are extratropical synoptic scale weather systems which cause significant precipitation over the Himalayas and surrounding areas during winter (December, January and February, DJF). Three intense WDs, 13-17 January 2002, 05-08 February 2002, and 11-13 February 2002, are chosen as two of the WDs are extensively studied by Hatwar et al. (Curr Sci 88:913-920, 2005) and one independent WD (Indian Meteorological Department, Delhi, Mausam 54(1):346-347, 2003) is considered. Firstly, it is planned to study model sensitivity with these WD cases, which are simulated with different combinations of cloud microphysics, planetary boundary layer and cumulus parameterization schemes in weather research and forecasting model to assess a better suite for the WD simulations. Sensitivity and error analyses carried out with different observations, show that the combination of Eta Ferrier or Eta Grid-scale cloud and precipitation microphysics scheme, Yonsei University scheme and Kain-Fritsch scheme has shown consistently lower error values. Further, the results suggest, that the model simulations of a WD capture the spatial distribution of precipitation, locations of low pressure region and the circulation patterns very well. It is observed that the WD system comprises of low pressure region in the vertical atmospheric column in form of a stationary surface low and a depression in the subtropical westerly jet moving eastwards. Further, the growth of convective cyclonic systems over the steep topographical region of the Himalayas is depicted by the increased positive vorticity and high values of CAPE, alluding to the propensity of WDs to cause orographically forced precipitation. WDs and associated precipitation show varied but significant impacts on the Indian winter climate such as snow cover variation and cold wave or fog conditions along with impact on winter crop production.

Dimri, A. P.; Chevuturi, A.

2014-02-01

127

Screening of different Fusarium species to select potential species for the synthesis of silver nanoparticles  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Onze diferentes espécies de Fusarium foram isoladas a partir de vários materiais vegetais infectados e selecionados para escolher uma espécie potencialmente importante para a síntese de nanopartículas de prata. Todos os isolados foram identificados com base nas características de cultivo e microscóp [...] icas usando as chaves de identificação de Fusarium. Para a confirmação e identificação preliminar dos isolados de espécies de Fusarium, a análise BLAST on-line foi utilizada. Das espécies isoladas onze mostraram a capacidade para a síntese de nanopartículas de prata. A síntese de nanopartículas de prata foi confirmada por espectroscopia de UV-Vis que monstrou um pico característico em torno de 420 nm. Além disso, a confirmação da síntese de nanopartículas de prata foi realizada utilizando a análise de rastreamento de nanoparticulas (nanoparticle tracking analysis-NTA), medidas de potencial zeta, espectroscopia de correlação de fótons (PCS), difratometria de raios X de pó (XRD), e microscopia eletrônica de transmissão (TEM). As menores nanopartículas de prata foram sintetizadas por F. oxysporum (3-25 nm), enquanto as maiores foram obtidas com F. solani (3-50 nm). Abstract in english Eleven different Fusarium species were isolated from various infected plant materials and screened to select a potential species for the synthesis of silver nanoparticles. All the isolates were identified on the basis of cultural and microscopic characteristics using Fusarium identification keys. Fo [...] r the confirmation of preliminary identified isolates of Fusarium species, online BLAST analysis was carried out. All the eleven species demonstrated the ability for synthesis of silver nanoparticles. This was confirmed by UV-Vis spectroscopy, which gave characteristic peak around 420 nm. Further confirmation of silver nanoparticles was carried out using nanoparticles tracking analysis (NTA), zeta potential, photon correlation spectroscopy (PCS), powder X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The smallest size of silver nanoparticles was synthesized by F. oxysporum (3-25 nm) and largest size silver nanoparticles were synthesized by F. solani (3-50 nm).

Swapnil C., Gaikwad; Sonal S., Birla; Avinash P., Ingle; Aniket K., Gade; Priscyla D., Marcato; Mahendra, Rai; Nelson, Duran.

128

Screening of different Fusarium species to select potential species for the synthesis of silver nanoparticles  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Onze diferentes espécies de Fusarium foram isoladas a partir de vários materiais vegetais infectados e selecionados para escolher uma espécie potencialmente importante para a síntese de nanopartículas de prata. Todos os isolados foram identificados com base nas características de cultivo e microscóp [...] icas usando as chaves de identificação de Fusarium. Para a confirmação e identificação preliminar dos isolados de espécies de Fusarium, a análise BLAST on-line foi utilizada. Das espécies isoladas onze mostraram a capacidade para a síntese de nanopartículas de prata. A síntese de nanopartículas de prata foi confirmada por espectroscopia de UV-Vis que monstrou um pico característico em torno de 420 nm. Além disso, a confirmação da síntese de nanopartículas de prata foi realizada utilizando a análise de rastreamento de nanoparticulas (nanoparticle tracking analysis-NTA), medidas de potencial zeta, espectroscopia de correlação de fótons (PCS), difratometria de raios X de pó (XRD), e microscopia eletrônica de transmissão (TEM). As menores nanopartículas de prata foram sintetizadas por F. oxysporum (3-25 nm), enquanto as maiores foram obtidas com F. solani (3-50 nm). Abstract in english Eleven different Fusarium species were isolated from various infected plant materials and screened to select a potential species for the synthesis of silver nanoparticles. All the isolates were identified on the basis of cultural and microscopic characteristics using Fusarium identification keys. Fo [...] r the confirmation of preliminary identified isolates of Fusarium species, online BLAST analysis was carried out. All the eleven species demonstrated the ability for synthesis of silver nanoparticles. This was confirmed by UV-Vis spectroscopy, which gave characteristic peak around 420 nm. Further confirmation of silver nanoparticles was carried out using nanoparticles tracking analysis (NTA), zeta potential, photon correlation spectroscopy (PCS), powder X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The smallest size of silver nanoparticles was synthesized by F. oxysporum (3-25 nm) and largest size silver nanoparticles were synthesized by F. solani (3-50 nm).

Swapnil C., Gaikwad; Sonal S., Birla; Avinash P., Ingle; Aniket K., Gade; Priscyla D., Marcato; Mahendra, Rai; Nelson, Duran.

1974-19-01

129

Phenolic content, antioxidant potential and Aedes aegyptii ecological friend larvicidal activity of some selected Egyptian plants.  

Science.gov (United States)

Polyphenols constitute a distinct group of natural compounds of medicinal importance exhibiting wide range of physiological activities as antioxidant, immunestimulant, antitumor and antiparasitic. Yellow fever and dengue fever are mosquito-borne infectious diseases transmitted by Aedes aegyptii, the presence of yellow fever in Sudan and dengue fever in Saudi Arabia are threats to Egypt with the reemerging of Ae. aegyptii in Southern Egypt, larvae control is feasible than flying adults. This work was conducted targeting estimation of the relative levels of total phenolic content, antioxidant potential and larvicidal activity of 110 selected Egyptian plants. The highest total phenolic contents were estimated in aqueous extracts of Coronilla scorpioides L., Forsskaolea tenacissima L., Crataegus sinaica Boiss., Pistacia khinjuk Boiss. and Loranthus acacia Benth.; they were 916.70 +/- 4.80, 813.70 +/- 4.16, 744.90 +/- 4.93, 549.00 +/- 3.93& 460.80 +/- 4.02 mg% while those of methanol extracts were estimated in Coronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Loranthus acacia and Pistacia khinjuk, they were 915.60-4.86, 664.60 +/- 4.16, 659.30 +/- 4.80, 590.80 +/- 4.49 & 588.00 +/- 3.85 mg% respectively. Investigation of the antioxidant potentials revealed that the most potent plants were Co-ronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Pistacia khinjuk and Loranthus acacia with calculated values of 454.80 +/- 4.83, 418.4 +/- 4.16, 399.10 +/- 4.90, 342.5 +/- 2.72 & 239.7 +/- 2.91% for aqueous extracts and 452.9 +/- 4.94, 389.6 +/- 4.6, 378.48 +/- 3.84, 352.3 +/- 3.06 & 346.5 +/- 2.98% for methanol extracts respectively while screening of larvicidal activity proved that Coronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Pistacia khinjuk and Loranthus acacia exhibited highest potency calculated as 22.53 +/- 2.01, 23.85 +/- 2.07, 28.17 +/- 2.06, 31.60 +/- 2.93 & 39.73 +/- 4.58 mg% aqueous extracts and 18.53 +/- 1.95, 18.8 +/- 1.67, 20.17 +/- 1.85, 23.28 +/- 2.7 & 28.48 +/- 3.9 mg% methanol ones respectively. PMID:23697028

El-Hela, Atef A; Abdel-Hady, Nevein M; Dawoud, Gouda T M; Hamed, Abdo M; Morsy, Tosson A

2013-04-01

130

Indirect ion selective electrode methods potentially overestimate peritoneal dialysate sodium losses.  

Science.gov (United States)

Measurements of dialysate sodium are used to estimate peritoneal dialysis sodium losses and sodium sieving, a measure of hydraulic permeability of the peritoneum. Peritoneal dialysates differ from serum samples in terms of pH, osmolality, protein and glucose concentration. We wished to determine whether these factors affected sodium measurement. Dialysate samples were taken from 52 consecutive peritoneal dialysis patients attending for a standard peritoneal dialysis equilibrium test (PET), 20 with standard lactate dialysate and 32 with neutral pH dialysate and sodium was measured by both flame photometry and indirect ion selective electrode (ISE). Sodium measured by ISE consistently overestimated that measured by flame photometer, mean bias 1.5?mmol/L (95% confidence limits 1.2 to 1.8), P?potentially lead to errors in both overestimating peritoneal sodium losses and the proportion of patients with ultrafiltration failure due to loss of sodium sieving. PMID:24206257

Persaud, Jahm; Thomas, Michael; Davenport, Andrew

2014-08-01

131

Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions.  

Science.gov (United States)

Herbal medicinals are being used by an increasing number of patients who typically do not advise their clinicians of concomitant use. Known or potential drug-herb interactions exist and should be screened for. If used beyond 8 weeks, Echinacea could cause hepatotoxicity and therefore should not be used with other known hepatoxic drugs, such as anabolic steroids, amiodarone, methotrexate, and ketoconazole. However, Echinacea lacks the 1,2 saturated necrine ring associated with hepatoxicity of pyrrolizidine alkaloids. Nonsteroidal anti-inflammatory drugs may negate the usefulness of feverfew in the treatment of migraine headaches. Feverfew, garlic, Ginkgo, ginger, and ginseng may alter bleeding time and should not be used concomitantly with warfarin sodium. Additionally, ginseng may cause headache, tremulousness, and manic episodes in patients treated with phenelzine sulfate. Ginseng should also not be used with estrogens or corticosteroids because of possible additive effects. Since the mechanism of action of St John wort is uncertain, concomitant use with monoamine oxidase inhibitors and selective serotonin reuptake inhibitors is ill advised. Valerian should not be used concomitantly with barbiturates because excessive sedation may occur. Kyushin, licorice, plantain, uzara root, hawthorn, and ginseng may interfere with either digoxin pharmacodynamically or with digoxin monitoring. Evening primrose oil and borage should not be used with anticonvulsants because they may lower the seizure threshold. Shankapulshpi, an Ayurvedic preparation, may decrease phenytoin levels as well as diminish drug efficacy. Kava when used with alprazolam has resulted in coma. Immunostimulants (eg, Echinacea and zinc) should not be given with immunosuppressants (eg, corticosteroids and cyclosporine). Tannic acids present in some herbs (eg, St John wort and saw palmetto) may inhibit the absorption of iron. Kelp as a source of iodine may interfere with thyroid replacement therapies. Licorice can offset the pharmacological effect of spironolactone. Numerous herbs (eg, karela and ginseng) may affect blood glucose levels and should not be used in patients with diabetes mellitus. PMID:9818800

Miller, L G

1998-11-01

132

Cytology of five species of subfamily Papaveroideae from the Western Himalayas.  

Science.gov (United States)

During the present course, population-based meiotic studies were carried out on five species of subfamily Papaveroideae from selected localities of Kashmir and Himachal Pradesh in the Western Himalayas (India). Varied intraspecific chromosome counts were reported for the first time in Argemone mexicana and Meconopsis latifolia, both existing on 2n = 2x = 14. The x = 7, confirmed for the first time from the newly found diploid cytotype, is suggested to be the primary chromosomal basic number for the Meconopsis. Furthermore, meiotic course was noted to be normal in Argemone ochroleuca, it varied from normal to abnormal in the populations of A. mexicana and Papaver dubium whereas it was invariably found to be abnormal in all the populations of Meconopsis aculeata and M. latifolia. These anomalous taxa were marked with meiotic abnormalities in the form of cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges resulting in abnormal microsporogenesis, and production of heterogeneous-sized fertile pollen grains along with reduced pollen fertility. PMID:22643839

Kumar, Sanjeev; Jeelani, Syed Mudassir; Rani, Savita; Gupta, Raghbir Chand; Kumari, Santosh

2013-02-01

133

Large landslides lie low: Vertical domains of denudation processes in the arid Himalaya-Karakoram orogen  

Science.gov (United States)

Large bedrock landslides (defined here as affecting >0.1 km2 in planform area) are thought to substantially contribute to denuding active mountain belts, and limiting the growth of topographic relief produced by concurrent tectonic uplift and fluvial or glacial incision. While most research on large landslides has focused on tectonically active, humid mountain belts with varying degrees of rainstorm and earthquake activity, lesser attention has been devoted to arid mountain belts. Especially in the Himalaya, where high denudation rates are commonly associated with high landslide activity, previous work has largely ignored landslide processes in the arid compartments of the orogen. This was motivation for us to compile a landslide inventory covering the arid Himalaya-Karakoram of NW India and N Pakistan within the Indus catchment. Our data set contains 493 rock-slope failures that we compiled from published studies and mapping from remote sensing imagery. Using an empirical volume-area scaling approach we estimate the total landslide volume at >250 km3. This is more than thousand times the contemporary annual sediment load in the Indus River. We analyse the distribution of these volumetrically significant landslides with respect to the regional hypsometry, contemporary glacier cover, and the distribution of rock glaciers. We find that large bedrock landslides in the arid Himalaya-Karakoram region preferentially detach near or from below the study area's median elevation, while glaciers and rock glaciers occupy higher elevations almost exclusively. This trend holds true for both the study area and parts thereof. The largest and highest-lying landslides occur in the Karakoram mountains, where local relief exceeds 6 km, and >90% of the landslide areas lie below the region's median elevation. Our analysis reveals a hitherto unrecognized vertical layering of denudation processes, with landslides chiefly operating below the median elevation, whereas mass transport by glaciers and rock glaciers dominates higher elevation bands. Given a SE-ward decreasing topographic amplitude and increasing median elevation, bedrock landslides tend to affect higher portions of the landscape, while their vertical drop heights decrease accordingly. We conclude that these vertical domains of denudation processes conflict with the view that large bedrock landslides contribute to limiting relief in active mountain belts, unless (a) more frequent and smaller rock falls take on this role, and/or (b) evidence of large bedrock landslides above the permanent snow line is being censored rapidly. In either case, our data favour a model where large rock-slope failures undermine the lower portions of arid high-relief landscapes near the limits of Pleistocene glaciations, potentially signalling a regional postglacial hillslope adjustment. We thus call for a more detailed and refined view on how large rock-slope failures contribute to shaping arid mountain belts.

Blöthe, Jan Henrik

2014-05-01

134

Looking at the roots of the highest mountains: the lithospheric structure of the Himalaya-Tibet and the Zagros orogens. Results from a geophysical-petrological study  

Science.gov (United States)

The Himalaya-Tibet and Zagros orogens are the two most prominent mountain belts built by continental collision. They are part of a huge belt of Cenozoic age which runs from the Pyrenees to Burma. In its central sector, the collision with the southern margin of the Eurasian plate has resulted not only in the building of mountain ranges over the north-eastern edges of the Arabian and Indian plates but also in widespread deformation 1000-3000 km from the suture zones. Zagros and Himalaya-Tibet orogens share many geodynamic processes but at different rates, amount of convergence and stage of development. The study of their present-day structures provides new insights into their quasi coeval collisional event pointing out differences and similarities in the mountain building processes. We present 2D crust and upper mantle cross-sections down to 400 km depth, along four SW-NE trending profiles. Two profiles cross the Zagros Mountains, running from the Mesopotamian Foreland Basin up to the Alborz and Central Iran. Two other profiles run through the Himalaya-Tibetan orogen: the western transect crosses the western Himalaya, Tarim Basin, Tian Shan Mountains and Junggar Basin; the eastern transect runs from the Indian shield to the Beishan Basin, crossing the eastern Himalaya, Tibetan Plateau, Qaidam Basin and Qilian Mountains. We apply the LitMod-2D code which integrates potential fields (gravity and geoid), isostasy (elevation) and thermal (heat flow and temperature distribution) equations, and mantle petrology. The resulting crust and upper mantle structure is constrained by available data on elevation, Bouguer anomaly, geoid height, surface heat flow and seismic data including P- and S-wave tomography models. Our results show distinct deformation patterns between the crust and the lithospheric mantle beneath the Zagros and Himalaya-Tibetan orogens, indicating a strong strain partitioning in both areas. At crustal level, we found a thickening beneath the Zagros and the Alborz ranges, more pronounced in the southern profile. At sub-crustal level, a lithospheric mantle thinning affects the whole area beneath the Zagros range extending to the north through the zone below the Alborz and the central Iran. In the Himalaya-Tibet region our results show stronger strain partitioning in the horizontal (east-west) direction than in the vertical (depth) direction. At crustal level, the Tibetan Plateau extends more than 1000 km in the eastern profile, whereas it is squeezed between the Himalayan Mountains and the Tarim Basin along the western profile (~600 km). At sub-crustal level, the lithospheric mantle is more homogeneous in thickness and mineral composition along the western profile than the eastern one. Finally, our results on mineral composition show that both collisional regions are characterised by a predominant lherzolitic lithospheric mantle, whereas we observe compositional variations around the suture zones, probably related to subduction and mantle delamination processes.

Tunini, L.; Jimenez-Munt, I.; Fernandez, M.; Villasenor, A.; Afonso, J. C.; Verges, J.

2013-12-01

135

Tectonic control on 10Be-derived erosion rates in the Garhwal Himalaya, India  

Science.gov (United States)

Erosion in the Himalaya is responsible for one of the greatest mass redistributions on Earth and has fueled models of feedback loops between climate and tectonics. Although the general trends of erosion across the Himalaya are reasonably well known, the relative importance of factors controlling erosion is less well constrained. Here we present 25 10Be-derived catchment-averaged erosion rates from the Yamuna catchment in the Garhwal Himalaya, northern India. Tributary erosion rates range between ~0.1 and 0.5 mm yr-1 in the Lesser Himalaya and ~1 and 2 mm yr-1 in the High Himalaya, despite uniform hillslope angles. The erosion-rate data correlate with catchment-averaged values of 5 km radius relief, channel steepness indices, and specific stream power but to varying degrees of nonlinearity. Similar nonlinear relationships and coefficients of determination suggest that topographic steepness is the major control on the spatial variability of erosion and that twofold to threefold differences in annual runoff are of minor importance in this area. Instead, the spatial distribution of erosion in the study area is consistent with a tectonic model in which the rock uplift pattern is largely controlled by the shortening rate and the geometry of the Main Himalayan Thrust fault (MHT). Our data support a shallow dip of the MHT underneath the Lesser Himalaya, followed by a midcrustal ramp underneath the High Himalaya, as indicated by geophysical data. Finally, analysis of sample results from larger main stem rivers indicates significant variability of 10Be-derived erosion rates, possibly related to nonproportional sediment supply from different tributaries and incomplete mixing in main stem channels.

Scherler, Dirk; Bookhagen, Bodo; Strecker, Manfred R.

2014-02-01

136

FATE OF SELECTED TOXIC COMPOUNDS UNDER CONTROLLED REDOX POTENTIAL AND PH CONDITIONS IN SOIL AND SEDIMENT-WATER SYSTEMS  

Science.gov (United States)

A study was conducted to determine the effects of pH and redox potential conditions on the degradation of selected synthetic organics. Also, the effects of these physicochemical parameters as well as other physical and chemical properties of soils and sediment-water systems on th...

137

Relation between spring water radon anomalies and seismic activity in Garhwal Himalaya  

Science.gov (United States)

The variations of spring water radon concentration and meteorological parameters were analysed in relation to the seismic activities in Garhwal Himalaya, India. The radon anomalies were classified on the basis of statistical treatment of the daily observations. The precise measurements of water discharge rate from the spring have been made along with radon measurements for earthquake precursory study. The earthquakes with epicentral distances less than 150 km were considered by an empirical relationship. Pre-, co-, and post-seismic changes in the radon concentration were taken carefully into account in the empirical relationship to establish this behaviour as a potential earthquake precursor. The empirical relationship has been validated by the radon data recorded from the spring waters. The magnitudes of the earthquakes were estimated by using the empirical relationship by introducing computed correlation coefficient of radon and meteorological parameters. The calculated magnitude of some local earthquakes matches exactly with the magnitude recorded by the laboratory seismograph. The possible mechanisms that may cause a radon anomaly are also discussed.

Ramola, Rakesh Chand

2010-10-01

138

Environmental impact assessment of mountain tourism in developing regions: A study in Ladakh, Indian Himalaya  

International Nuclear Information System (INIS)

Mountain tourism in developing countries is becoming a growing environmental concern due to extreme seasonality, lack of suitable infrastructures and planning, and interference with fragile ecosystems and protected areas. This paper presents a study devoted to assess the adverse environmental impacts of tourism, and in particular of trekking-related activities, in Ladakh, Indian Himalaya. The proposed approach is based on the use of Geographical Information System (GIS) modeling and remote sensing imageries to cope with the lack of data that affect the region. First, stressors associated with trekking, and environmental receptors potentially affected were identified. Subsequently, a baseline study on stressors (trail use, waste dumping, camping, pack animal grazing and off-road driving) and receptors (soil, water, wildlife, vegetation) was conducted through field work, data collection, and data processing supported by GIS. Finally, impacts were modeled by considering the intensity of the stressors, and the vulnerability and the value of the receptors. The results were spatially aggregated into watershed units, and combined to generate composite impact maps. The study concluded that the most affected watersheds are located in the central and southeastern part of Ladakh, along some of the most visited trails and within the Hemis and the Tsokar Tsomoriri National parks. The main objective of the study was to understand patterns of tourism-induced environmental degradatiof tourism-induced environmental degradation, so as to support mitigation interventions, as well as the development of suitable tourism policies.

139

Plant operator selection system for evaluating employment candidates' potential for success in electric power plant operations positions  

International Nuclear Information System (INIS)

The Plant Operator Selection System is a battery of tests and questionnaires that can be administered to job candidates in less than three hours. Various components of the battery measure what a job candidate has accomplished in previous educational and work situations, how well a candidate compares with others on a number of important aptitudes or abilities, and whether or not a candidate possesses the kind of personal stability required in power plant operations positions. A job candidate's answers to the tests and questionnaires of the Plant Operator Selection System are scored and converted to an OVERALL POTENTIAL INDEX. Values of the OVERALL POTENTIAL INDEX [OPI] range between 0 and 15. Candidates with high OPI values are much more likely to become effective and successful plant operators than candidates with low OPI values. It is possible to estimate the financial advantages to a company of using the Plant Operator Selection System in evaluating candidates for plant operations jobs

140

Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India  

Directory of Open Access Journals (Sweden)

Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as a major sink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied under different plantation forest ecosystems comprising of eight different tree species: Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnusnitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57±48.99tha-1 and below ground (42.47±10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera(118.37±1.49 tha-1 and minimum (36.50±9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86±10.34 tha-1 in Alnus nitida, and minimum (170.83±20.60 tha-1 in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79±2.0 tha-1. Carbon sequestration (7.91±3.4 tha-1 and CO2 mitigation potential (29.09±12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions for sustainable management of fragile hilly ecosystem.

Bandana Devi

2013-05-01

 
 
 
 
141

Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India  

Directory of Open Access Journals (Sweden)

Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as amajorsink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied underdifferent plantation forest ecosystems comprising of eight different tree species viz. Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnus nitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57 ? 48.99 tha-1 and below ground (42.47 ? 10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera (118.37 ? 1.49 tha-1 and minimum (36.50 ? 9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86? 10.34 tha-1 in Alnus nitida, and minimum (170.83? 20.60 tha-1in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79 ? 2.0 tha-1. Carbon sequestration (7.91? 3.4 tha-1 and CO2 mitigation potential (29.09 ? 12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions forsustainable management of fragile hilly ecosystem. 

Bandana Devi

2013-07-01

142

Alteraciones musculares en montañistas que ascendieron a Los Himalayas  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish El ascenso a los Montes Himalayas de un grupo de escaladores venezolanos permitió la obtención de muestras de músculo esquelético dos meses antes y un mes después de la expedición, con el objeto de estudiar los cambios producidos por la altura. Se tomó biopsia del músculo quadriceps femoris con la a [...] guja de Bergström en 5 sujetos dos meses antes, y en 4 sujetos un mes después de realizada la expedición. Las muestras fueron procesadas para estudio histoquímico con el objeto de clasificar los tipos de fibras musculares mediante la reacción de la adenosina trifosfatasa miofibrilar; los capilares se evidenciaron con la reacción de la a-amilasa-PAS. Además se estudió la ultraestructura con microscopía electrónica de transmisión. Se encontró que los sujetos cuyo músculo estaba en mejores condiciones alcanzaron la meta de 7.100 metros de altura. Estos sujetos presentaron posteriormente daño muscular segmentario marcado, en forma de atrofia muscular, daño capilar e infiltración de macrófagos. No hubo modificación en la proporción de los tipos de fibras. Se concluye que la actuación depende del estado previo del músculo y que la hipoxia, el esfuerzo muscular y el frío combinados, producen lesiones musculares segmentarias que persisten al menos por un mes. Abstract in english Skeletal muscle needle biopsies were obtained from quadriceps femoris muscle in five venezuelan climbers, two months before, and in four of the subjects, one month after an expedition to the Himalayas Mountains. In the samples, fibre types were determined by the miofibrillar adenosin triphosphatase [...] reaction, and capillaries were stained with the a-amylase-PAS reaction. Part of each sample was processed for ultrastructural study. The climbers performance was related to the previous state of the muscle. The three subjects that reached the goal of 7100 m altitude were those with normal of slightly altered muscles in the biopsy before the expedition. One month after the descent, muscle showed segmental alterations manifested as atrophy, capillary damage and infiltration of macrophages. No change was found in muscle fibre proportions. It is concluded that performance of the climbers depends on the previous state of skeletal muscle, and that the combined effect of altitude, exercise and cold produced segmental damage in skeletal muscle.

SH, Torres; HJ, Finol; A, Brito; H, Rivera.

143

Estimation of Q p and Q s of Kinnaur Himalaya  

Science.gov (United States)

The attenuation characteristics of the Kinnaur area of the North West Himalayas were studied using local earthquakes that occurred during 2008-2009. Most of the analyzed events are from the vicinity of the Panjal Thrust (PT) and South Tibetan Detachment Thrust, which are well-defined tectonic discontinuities in the Himalayas. The frequency-dependent attenuation of P and S waves was estimated using the extended coda normalization method. Data from 64 local earthquakes recorded at 10 broadband stations were used. The coda normalization of the spectral amplitudes of P and S waves was done at central frequencies of 1.5, 3, 6, 9, and 12 Hz. Q p increases from about 58 at 1.5 Hz to 706 at 12 Hz, and Q s increases from 105 at 1.5 Hz to 1,207 at 12 Hz. The results show that the quality factors for both P and S waves ( Q p and Q s) increase as a function of frequency according to the relation Q = Q o f n , where Q o is the corresponding Q value at 1 Hz frequency and " n" is the frequency relation parameter. We obtained Q p = (47 ± 2) f (1.04±0.04) and Q s = (86 ± 4) f (0.96±0.03) by fitting power law dependency model for the estimated values of the entire study region. The Q 0 and n values show that the region is seismically very active and the crust is highly heterogeneous. There was no systematic variation of values of Q p and Q s at different frequencies from one tectonic unit to another. As a consequence, average values of these parameters were obtained for each frequency for the entire region, and these were used for interpretation and for comparison with worldwide data. Q p values lie within the range of values observed for some tectonically active regions of the world, whereas Q s values were the lowest among the values compared for different parts of the world. Q s/ Q p values were >1 for the entire range of frequencies studied. All these factors indicate that the crust is highly heterogeneous in the study region. The high Q s/ Q p values also indicate that the region is partially saturated with fluids.

Kumar, Naresh; Mate, Shonkholen; Mukhopadhyay, Sagarika

2014-01-01

144

Selection of Ukrainian Light Industry Enterprises Innovation Potential Improvement Model in the Technology Transfer System  

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Full Text Available The article studies the necessity to improve the innovation potential of light industry enterprises. The essence of light industry enterprises innovation potential improvement in the technology transfer system is defined. Some approaches and key elements, used for the construction of such model are identified. The author’s model to improve light industry enterprises innovation potential in the technology transfer system is proposed. The principles of the innovation potential improvement system, taken into account in the course of model construction practice are described.

Irina V. Rodionova

2013-01-01

145

The potential for evolutionary responses to cell-lineage selection on growth form and its plasticity in a red seaweed.  

Science.gov (United States)

Despite much theoretical discussion on the evolutionary significance of intraclonal genetic variation, particularly for modular organisms whose lack of germ-soma segregation allows for variants arising in clonal growth to contribute to evolutionary change, the potential of this variation to fuel adaptation remains surprisingly untested. Given intraclonal variation, mitotic cell lineages, rather than sexual offspring, may frequently act as units of selection. Here, we applied artificial selection to such lineages in the branching red seaweed Asparagopsis armata, targeting aspects of clonal growth form and growth-form plasticity that enhance light acquisition on patchy subtidal reefs and predicting that a genetic basis to intraclonal variation may promote significant responses that cannot accompany phenotypic variation alone. Cell-lineage selection increased variation in branch proliferation among A. armata genets and successfully altered its plasticity to light. Correlated responses in the plasticity of branch elongation, moreover, showed that cell-lineage selection may be transmitted among the plasticities of growth-form traits in A. armata via pleiotropy. By demonstrating significant responses to cell-lineage selection on growth-form plasticity in this seaweed, our study lends support to the notion that intraclonal genetic variation may potentially help clonal organisms to evolve adaptively in the absence of sex and thereby prove surprisingly resilient to environmental change. PMID:19115857

Monro, Keyne; Poore, Alistair G B

2009-02-01

146

Selection and characterization of potential sites for a spent nuclear fuel repository in Sweden  

International Nuclear Information System (INIS)

Geological, geochemical, geophysical, rock mechanical, hydrogeochemical and hydrogeological investigations are included in the site selection studies for a spent nuclear fuel repository in Sweden. The investigations started in 1977 and are carried out in crystalline rock. The final site will be selected around the year 2000 through a screening process of investigated sites. The field studies generate numerous data that are compiled into a descriptive model for each site. The descriptive model forms the basis for the numerical calculation of the groundwater flow within the site. This paper presents the major instruments and methods that are used in the ongoing program as well as some of the obtained results

147

A small synthetic molecule forms selective potassium channels to regulate cell membrane potential and blood vessel tone.  

Science.gov (United States)

In living cell membranes, K(+) permeability is higher than that of other ions such as Na(+) and Cl(-) owing to abundantly expressed K(+) channels. Polarized membrane potential is mainly established by K(+) outward flow because the K(+) concentration in the intracellular side is much higher than that in the extracellular side. We have found that the small synthetic molecule 1 is capable of self-assembling into selective K(+) channels, enhancing K(+) permeability and hyperpolarizing liposome membrane potential. Interestingly, molecule 1 also functions as K(+) channel hyperpolarizing living cell membrane potential and relaxing agonist-induced blood vessel contraction. Therefore, it may have the potential to become a lead compound for the treatment of human diseases associated with K(+) channel dysfunction. PMID:25183342

Zha, Hui-Yan; Shen, Bing; Yau, Kwok-Hei; Li, Shing-To; Yao, Xiao-Qiang; Yang, Dan

2014-11-01

148

Dynamic of potential of ion-selective electrodes based on podands with phosphoryl-containing end group  

International Nuclear Information System (INIS)

The dynamic properties of ion-selective electrodes based on phosphoryl-containing podands have been examined as a function of the structure and concentration of podands and the concentration and nature of the potential-determining metal cation (alkali metals) and its counterion. It is shown that the rate of the reaction of potential formation is inversely proportional to the formation constant of the potential-determining complex ion. The reaction of potential formation proceeds under conditions of diffusion-kinetic control, and complex ions of different composition apparently participate in the membrane transport. It is confirmed that an addition of potassium tetra (p-chlorophenyl)borate considerably increases the linear range of electrode operation in perchlorate solutions and improves its kinetics properties.13 refs., 7 figs

149

Geological investigations at a high altitude, remote coal mine on the Northwest Pakistan and Afghanistan frontier, Karakoram Himalaya  

Energy Technology Data Exchange (ETDEWEB)

The Northwest Pakistan and Afghanistan frontier is located one of the most remote, inaccessible, and inhospitable part of the Himalayan orogenic belt. In this region, two of the world's largest and most distinct mountain belts intersect; the Karakoram Himalaya (mainly in Pakistan) and the Hindu Kush (mainly in Afghanistan). Located at high altitude, in a remote part of Northwest Pakistan, close to the border with Afghanistan, tribal villagers began excavating a series of audits into the steep mountain slopes, beneath glaciers, to extract valuable coal and carbonaceous shale resources. These were discovered in 1996, by the villagers, whilst hunting, and may represent some of the highest mine workings in the world. Small-scale mining operations subsequently developed using rudimentary mining methods and the mine became known as the Reshit or Pamir Coal Mine.The coal deposits are sedimentary, highly disturbed and tectonised, having been subjected to multiple phases of orogenic crustal deformation. The coal occurs as discrete lenses, several tens of metres in their lateral dimension, between steeply dipping, overturned and thrusted limestone beds of Jurassic age. The coal provided a vital, alternative source of fuel for the villagers since the local, traditional fuel supply was wood, which had become severely depleted, and imports of kerosene from neighbouring China and Afghanistan were too expensive. The mining operations experienced severe problems. These included several collapses of mine entrances, the failure of the adits to intersect the coal-bearing zones, the potential threat of geological hazards, mining-induced hazards and harsh high-altitude operating conditions, particularly during the winter months. International aid was provided to assist the villagers and a geological investigation was commissioned to investigate the problems at the mine. The geology of Karakoram Himalaya is relatively poorly understood. Until recently the region was restricted to foreign visitors and large areas of this mountain belt are virtually unmapped. Existing geological and topographic maps are difficult to obtain or are unavailable due to the close proximity of political frontiers, national borders and security reasons. The mineral resource potential of this region is virtually unknown. Few western geologists have visited this area due to its inaccessibility and political constraints, being situated close the frontiers with China, Afghanistan, and the disputed Pakistan and India territory of Kashmir.The Pakistan and Afghanistan border, is once again, now closed to foreign visitors. The objectives of this paper are to document the occurrence of coal and carbonaceous shale, at high altitude, in the Karakoram Himalaya and to provide details on the geology, geological hazards, reserves and labour-intensive mining operations. These observations and information may provide the basis for future mineral exploration, mining-geology, mining-engineering, feasibility studies and engineering geological investigation in the Karakoram Himalaya.

Donnelly, Laurance J. [Chartered Geologist, Halcrow Group Ltd., Deanway Technology Centre, Wilmslow Road, Handforth, Cheshire, SK9 3FB (United Kingdom)

2004-12-03

150

Ethnobotanical uses of Biofencing Plants in Himachal Pradesh, Northwest Himalaya  

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Full Text Available The aim of this study is to document the traditional knowledge on the utilization of Biofencing plants of Himachal Pradesh, Northwest Himalaya. The study was imperative because of dearth in the data pertaining to Biofencing plants in the study areas. The whole study area was stratified into three zones and a widespread field survey and random sampling method was adopted to assess the live fencing diversity of the region. The region occupies total 61 species. 10 (trees, 45 (shrubs, 4 (herbs and 2 were climbers. These belong to the 25 families. Rosaceae, Fabaceae, Berberidaceae, Elaeagnaceae and Euphorbiaceae are dominant families. Among genera, Berberis and Rosa are dominant. Of the total, 55 species are medicinally important and among these 20% are used for stomach disorders; 17% (skin complaints, 14% (asthma, 11% (fever and joint pains, 3% (aphrodisiac and snake bite, 1% (anticancerous and nerve disorders. Ethnobotanical assessment showed that 33 of the recorded species are used as fuel, 20 (edible, 8 (fodder and 4 (fiber and ornamental. This traditional knowledge of Biofencing plants contributes to the conservation of biodiversity and provides resource of economic and ecological interest and also decreasing the pressure on forests. So there is need to encourage the practice of using plant species for fencing in this region.

Pankaj Sharma

2013-01-01

151

Deep structure over the eastern syntaxis of the Himalaya  

International Nuclear Information System (INIS)

Complete text of publication follows. Magnetotelluric surveys were conducted over two profiles for mapping the major tectonic features over the eastern syntaxial bend. These studies over the main frontal thrust and Main boundary thrust of the Himalaya and the Mishmi thrust in the Indo Burman range have shown that the signatures of these thrusts at deeper level are not coincident with their corresponding surface expressions. Thus main frontal and the main boundary thrusts are traced about 20 km south of the surface manifestations where as the Mishmi thrust at deeper levels is about 25 km west of the location observed on the surface. The global positioning studies (Gan, W, et al. (2007) J. Geophys. Res. Article No: B08416) are indicative of eastward (transverse to the strike) movements of the sedimentary overburden north of the main frontal thrust, in this region. Another conspicuous feature is the south dipping thrust / reverse fault delineated to the north of the Main frontal thrust earlier observed in the Tawang-Bomdilla region (Gokarn et al, 2008, 19th EM induction workshop, Beijing China). Its signatures at shallow depth in this region are however obscured by the presence of then supracrustal deposits of the Abhor volcanics and Yinkiang formations occurring in small discrete patches in the close vicinity of this feature.

152

Phytochemical diversity of Murraya koenigii (L.) Spreng. from Western Himalaya.  

Science.gov (United States)

Murraya koenigii (L.) Spreng. (Rutaceae), commonly known as 'curry leaf tree', is a popular spice and condiment of India. To explore the diversity of the essential-oil yield and aroma profile of curry leaf, growing wild in foot and mid hills of north India, 58 populations were collected during spring season. M. koenigii populations were found to grow up to an altitude of 1487?m in north India. Comparative results showed considerable variations in the essential-oil yield and composition. The essential-oil yield varied from 0.14 to 0.80% in shade-dried leaves of different populations of M. koenigii. Analysis of the essential oils by GC and GC/MS, and the subsequent classification by statistical analysis resulted in four clusters with significant variations in their terpenoid composition. Major components of the essential oils of investigated populations were ?-pinene (2; 4.5-71.5%), sabinene (3; myrcene (5; 0.5-2.1%). Comparison of the present results with those in earlier reports revealed new chemotypes of M. koenigii in investigated populations from Western Himalaya. The present study documents M. koenigii populations having higher amounts of sabinene (3; up to 66.1%) for the first time. PMID:23576349

Verma, Ram S; Chauhan, Amit; Padalia, Rajendra C; Jat, Sanjeev K; Thul, Sanjog; Sundaresan, Velusamy

2013-04-01

153

Treeline dynamics with climate change at the central Nepal Himalaya  

Science.gov (United States)

Treeline shifting in tandem with climate change has widely been reported from various parts of the world. In Nepal, several impacts of climate change on the physical environment have been observed, but study on the biological impacts is lacking. This dendrochronological study was carried out at the treeline in the high mountain slope of Kalchuman Lake (3750-4003 m a.s.l.) area of Manaslu Conservation Area in the central Nepal Himalaya to explore the impact of climate change on the treeline dynamic. Two belt transect plots (size: 20 m wide, > 250 m long) were laid which included treeline as well as tree species limit. Ecological mapping of all individuals of dominant trees Abies spectabilis and Betula utilis was done and their tree cores were collected. Stand character and age distribution revealed an occurrence of more matured B. utilis (max. age 198 years) compared to A. spectabilis (max. age 160 years). A. spectabilis contained an overwhelmingly high population (89%) of younger plants (sensitive to maximum and minimum temperature rather than average temperature. The growth of the B. utilis was mainly limited by moisture stress during the pre-monsoon season. As these two species presented species-specific responses to climate change with differential pattern in regeneration condition, much wider differences are anticipated in their population status as climate continues to change throughout the century.

Gaire, N. P.; Koirala, M.; Bhuju, D. R.; Borgaonkar, H. P.

2014-07-01

154

Cytological evaluation of Apiaceae Lindl. from Western Himalayas.  

Science.gov (United States)

The present paper deals with cytological studies on 31 populations covering 17 species belonging to 10 genera of Apiaceae from Western Himalayas. The chromosome numbers in the two species as Chaerophyllum capnoides (n = 11) and Heracleum brunonis (n = 11), along with additional cytotypes for Pimpinella acuminata (n = 9) and Sium latijugum (n = 12) have been reported for the first time on world-wide basis. The genus Pleurospermum, although cytologically worked out earlier from outside India, its species densiflorum (n = 11) makes first representation of the genus from India. Besides, the chromosome number in Chaerophyllum aromaticum (n = 11) have been worked out for the first time from India. The course of meiosis varies from normal to abnormal in different populations of Chaerophyllum villosum, Pimpinella achilleifolia and Sium latijugum while abnormal meiotic course has been observed in all the studied populations of Chaerophyllum acuminatum, C. aromaticum, C. capnoides, Pimpinella acuminata, P. diversifolia, Pleurospermum densiflorum and Vicatia coniifolia. Such taxa are marked with meiotic abnormalities in the form of cytomixis, chromatin stickiness, formation of laggards and bridges resulting into abnormal microsporogenesis. The occurrence of structural heterozygosity has been recorded in the Chaerophyllum acuminatum and C. aromaticum. The effect of these abnormalities is clearly seen on the pollen size and fertility. PMID:25181856

Kumar, S; Jeelani, S M; Rani, S; Kumari, S; Gupta, R C

2014-01-01

155

Radon in groundwater of eastern Doon valley, Outer Himalaya  

International Nuclear Information System (INIS)

The radon content in water may serve as a useful tracer for several geohydrological processes. The hydrodynamic factor, presence of radium in host rocks, as well as the soil porosity and permeability control its concentration in groundwater. In order to understand the factors that control the occurrence of radon in groundwater of Doon valley in Outer Himalaya, a total of 34 groundwater samples were collected from handpumps and tubewells covering three hydrogeological units/areas in the eastern part of Doon valley. Radon variation in tubewells and handpumps varies from 25.4±1.8 to 92.5±3.4 Bq/l with an average of 53.5±2.6 Bq/l. A significant positive correlation between radon concentration and depth of the wells was observed in the Doiwala-Dudhli and Jolleygrant areas suggesting that radon concentration increases with drilling depth in areas consisting of sediments of younger Doon gravels, whereas samples of the Ganga catchment show negative correlation. The high radon levels at shallower depths in the Ganga catchment (consisting of fluvial terraces of Ganga basin) indicate uranium-rich sediments at shallower depth

156

Earthquakes in India and the Himalaya: tectonics, geodesy and history  

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Full Text Available The record of earthquakes in India is patchy prior to 1800 and its improvement is much impeded by its dispersal in a dozen local languages, and several colonial archives. Although geological studies will necessarily complement the historical record, only two earthquakes of the dozens of known historical events have resulted in surface ruptures, and it is likely that geological data in the form of liquefaction features will be needed to extend the historical record beyond the most recent few centuries. Damage from large Himalayan earthquakes recorded in Tibet and in Northern India suggests that earthquakes may attain M = 8.2. Seismic gaps along two-thirds of the Himalaya that have developed in the past five centuries, when combined with geodetic convergence rates of approximately 1.8 m/cy, suggests that one or more M = 8 earthquakes may be overdue. The mechanisms of recent earthquakes in Peninsular India are consistent with stresses induced in the Indian plate flexed by its collision with Tibet. A region of abnormally high seismicity in western India appears to be caused by local convergence across the Rann of Kachchh and possibly other rift zones of India. Since the plate itself deforms little, this deformation may be related to incipient plate fragmentation in Sindh or over a larger region of NW India.

R. Bilham

2004-06-01

157

1991-1992 GPS measurements across the Nepal Himalaya  

Science.gov (United States)

In March 1991 35 control points were measured in the collision zone between the Indian and Asian plates using the Global Positioning System (GPS). Twenty-eight points are located in the Nepal Himalaya, and 7 in S. and E. Tibet. In October 1992, 6 of the Nepal points were remeasured together with 3 bedrock points in Bihar State, India, 5 points in E. Tibet, and one in Urumchi. The average WRMS GPS position repeatability between 1991 and 1992 improved from 8 mm to 5 mm in the north, 16 mm to 7 mm in the east, and 32 mm to 25 mm in the vertical components. Himalayan convergence rates of 20 mm/yr may be resolved to 10% accuracy within 5 years with these uncertainties. Unless improved vertical measurement techniques are introduced many decades must elapse before regional secular vertical motions may be resolved. The 1991.3-1992.8 measurements are consistent with geologically determined Himalayan convergence rates of less than 20 mm/year.

Jackson, Michael E.; Bilham, Roger

1994-06-01

158

Ethnobotanical uses of biofencing plants in Himachal Pradesh, Northwest Himalaya.  

Science.gov (United States)

The aim of this study is to document the traditional knowledge on the utilization of Biofencing plants of Himachal Pradesh, Northwest Himalaya. The study was imperative because of dearth in the data pertaining to Biofencing plants in the study areas. The whole study area was stratified into three zones and a widespread field survey and random sampling method was adopted to assess the live fencing diversity of the region. The region occupies total 61 species. 10 (trees), 45 (shrubs), 4 (herbs) and 2 were climbers. These belong to the 25 families. Rosaceae, Fabaceae, Berberidaceae, Elaeagnaceae and Euphorbiaceae are dominant families. Among genera, Berberis and Rosa are dominant. Of the total, 55 species are medicinally important and among these 20% are used for stomach disorders; 17% (skin complaints), 14% (asthma), 11% (fever and joint pains), 3% (aphrodisiac and snake bite), 1% (anticancerous and nerve disorders). Ethnobotanical assessment showed that 33 of the recorded species are used as fuel, 20 (edible), 8 (fodder) and 4 (fiber and ornamental). This traditional knowledge of Biofencing plants contributes to the conservation of biodiversity and provides resource of economic and ecological interest and also decreasing the pressure on forests. So there is need to encourage the practice of using plant species for fencing in this region. PMID:24517012

Sharma, Pankaj; Devi, Usha

2013-12-15

159

Monsoon variability in the Himalayas under the condition of global warming  

International Nuclear Information System (INIS)

An ice core-drilling program was carried out at the accumulation area of Dasuopu glacier (28deg23'N, 85deg43'E, 7100 m a.s.l.) in the central Himalayas in 1997. The ice core was analyzed continuously for stable isotopes (?18O), and major ions throughout the core. Cycles indicated by ?18O, cations were identified and counted as seasonal fluctuations as annual increment from maximum to maximum values. Reconstructed 300-year annual net accumulation (water equivalent) from the core, with a good correlation to Indian monsoon, reflects a major precipitation trend in the central Himalayas. The accumulation trend, separated from the time series, shows a strong negative correlation to Northern Hemisphere temperature. Generally, as northern hemisphere temperature increases 0.1degC, the accumulation decreases about 80 mm, reflecting monsoon rainfall in the central Himalayas has decreased over the past decades in the condition of global warming. (author)

160

The Relationship of Selected Temperament Characteristics to Creative Potential in Preschool Children.  

Science.gov (United States)

In this study, the relationship of selected characteristics of temperament and ideational fluency in preschool children was explored. Subjects were 58 children ranging in age from 46 to 72 months, with a sample mean age of 57 months. All subjects were given the Multidimensional Stimulus Fluency Measure (MSFM), a test of ideational fluency. Their…

Bomba, Anne K.; Moran, James D., III

 
 
 
 
161

Dopamine D3 receptor antagonists: the quest for a potentially selective PET ligand. Part 3: Radiosynthesis and in vivo studies  

DEFF Research Database (Denmark)

Compound 1 is a potent and selective antagonist of the dopamine D(3) receptor. With the aim of developing a carbon-11 labeled ligand for the dopamine D(3) receptor, 1 was selected as a potential PET probe. [(11)C]1 was obtained by palladium catalyzed cross coupling using [(11)C]cyanide and 4 with a specific activity of 55.5+/-25.9GBq/micromol (1.5+/-0.7Ci/micromol). [(11)C]1 was tested in porcine and non-human primate models to assess its potential as a radioligand for PET imaging of the dopamine D(3) receptor. We conclude that in both species and despite appropriate in vitro properties, [(11)C]1 does not show any specific signal for the dopamine D(3) receptor.

Bennacef, Idriss; Salinas, Cristian A

2009-01-01

162

Substrate selection for fundamental studies of electrocatalysts and photoelectrodes: inert potential windows in acidic, neutral, and basic electrolyte.  

Science.gov (United States)

The selection of an appropriate substrate is an important initial step for many studies of electrochemically active materials. In order to help researchers with the substrate selection process, we employ a consistent experimental methodology to evaluate the electrochemical reactivity and stability of seven potential substrate materials for electrocatalyst and photoelectrode evaluation. Using cyclic voltammetry with a progressively increased scan range, we characterize three transparent conducting oxides (indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide) and four opaque conductors (gold, stainless steel 304, glassy carbon, and highly oriented pyrolytic graphite) in three different electrolytes (sulfuric acid, sodium acetate, and sodium hydroxide). We determine the inert potential window for each substrate/electrolyte combination and make recommendations about which materials may be most suitable for application under different experimental conditions. Furthermore, the testing methodology provides a framework for other researchers to evaluate and report the baseline activity of other substrates of interest to the broader community. PMID:25357131

Benck, Jesse D; Pinaud, Blaise A; Gorlin, Yelena; Jaramillo, Thomas F

2014-01-01

163

Substrate Selection for Fundamental Studies of Electrocatalysts and Photoelectrodes: Inert Potential Windows in Acidic, Neutral, and Basic Electrolyte  

Science.gov (United States)

The selection of an appropriate substrate is an important initial step for many studies of electrochemically active materials. In order to help researchers with the substrate selection process, we employ a consistent experimental methodology to evaluate the electrochemical reactivity and stability of seven potential substrate materials for electrocatalyst and photoelectrode evaluation. Using cyclic voltammetry with a progressively increased scan range, we characterize three transparent conducting oxides (indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide) and four opaque conductors (gold, stainless steel 304, glassy carbon, and highly oriented pyrolytic graphite) in three different electrolytes (sulfuric acid, sodium acetate, and sodium hydroxide). We determine the inert potential window for each substrate/electrolyte combination and make recommendations about which materials may be most suitable for application under different experimental conditions. Furthermore, the testing methodology provides a framework for other researchers to evaluate and report the baseline activity of other substrates of interest to the broader community. PMID:25357131

Gorlin, Yelena; Jaramillo, Thomas F.

2014-01-01

164

Hillslope-channel coupling in the Nepal Himalayas and threat to man-made structures: The middle Kali Gandaki valley  

Science.gov (United States)

In mountain areas, the confinement of valleys favours landslide interaction with rivers, causing channel changes or short-lived dams and lakes that may threaten trails, roads and human settlements. Their impacts may occur successively in space and time, and they affect randomly the functioning of the sediment fluxes. The present study focuses on the interaction patterns between unstable mountain slopes and the Kali Gandaki River, in the Nepal Himalayas. In this valley, the deepest on earth, a road linking the Myagdi and Mustang districts has been under construction for the past 5 years, either cutting into the bedrock or crossing areas affected episodically by debris slides, earth flows, debris flows and rock slides. On the basis of the geomorphic evolution observed over the last three decades, we assess the potential threats that now arise following completion of the road. We mapped three areas of recurrent mass wasting features characteristic of the most frequent situations encountered in this valley. We analyzed the combination of the hydro-geomorphic processes involved. With the use of a DEM, we assessed the volume and spatial impact of temporary river dams on infrastructure located along the valley floor. We estimated hydraulic parameters to document the geomorphic efficiency of river flooding after dam breaching. We reconstructed the spatial extent of (1) areas threatened by backwater flooding upstream of the dams and (2) areas threatened by the collapse of the dams. We describe the current geomorphic and sedimentary adjustments still at work along the valley sides. Our findings confirm that in the High Himalaya, medium scale landslides (10 5-6 m 3) play a major role in the overall process of denudation and sediment transfer. They highly influence the transient nature of bedload transport in the channel. In reducing the residence time of sediments in temporary, spatially limited traps of the valley bottom, they enhance the vulnerability of land and people attracted by a roadside location.

Fort, M.; Cossart, E.; Arnaud-Fassetta, G.

2010-12-01

165

Potential productivity and yield gap of selected crops in the rainfed regions of India, Thailand, and Vietnam  

Digital Repository Infrastructure Vision for European Research (DRIVER)

ICRISAT's intervention in the project improving management of natural resources for sustainable rainfed agriculture funded by the Asian Development Bank aims to increase the productivity and sustainability of the medium and high water-holding capacity soils in the intermediate rainfall ecoregion of India, Thailand, and Vietnam. This study examined the potential yield and yield gap of selected crops predominantly grown in the target regions where the project is operational. We used the CROPGRO...

Piara Singh; Vijaya, D.; Nt, Chinh; Aroon Pongkanjana; Ks, Prasad; Srinivas, K.; Sp, Wani

2006-01-01

166

Interactions of biotic and abiotic environmental factors in an ectomycorrhizal symbiosis, and the potential for selection mosaics  

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Full Text Available Abstract Background Geographic selection mosaics, in which species exert different evolutionary impacts on each other in different environments, may drive diversification in coevolving species. We studied the potential for geographic selection mosaics in plant-mycorrhizal interactions by testing whether the interaction between bishop pine (Pinus muricata D. Don and one of its common ectomycorrhizal fungi (Rhizopogon occidentalis Zeller and Dodge varies in outcome, when different combinations of plant and fungal genotypes are tested under a range of different abiotic and biotic conditions. Results We used a 2 × 2 × 2 × 2 factorial experiment to test the main and interactive effects of plant lineage (two maternal seed families, fungal lineage (two spore collections, soil type (lab mix or field soil, and non-mycorrhizal microbes (with or without on the performance of plants and fungi. Ecological outcomes, as assessed by plant and fungal performance, varied widely across experimental environments, including interactions between plant or fungal lineages and soil environmental factors. Conclusion These results show the potential for selection mosaics in plant-mycorrhizal interactions, and indicate that these interactions are likely to coevolve in different ways in different environments, even when initially the genotypes of the interacting species are the same across all environments. Hence, selection mosaics may be equally as effective as genetic differences among populations in driving divergent coevolution among populations of interacting species.

Hoeksema Jason D

2008-05-01

167

Late Pleistocene and Holocene large magnitude earthquakes along Himalayan Frontal Thrust in the Central Seismic Gap in NW Himalaya, Kala Amb, India  

Science.gov (United States)

The Himalayan Frontal Thrust (HFT) forms the southernmost active tectonic mountain front of the Himalaya. To understand the ongoing tectonics further, paleoseismological study has been carried out in the vicinity of the HFT system along the Himalayan Front near Kala Amb, India. The trench excavation survey conducted across an explicit surface exposure of the HFT exhibits two distinct faults considered to be associated with the reactivation of the HFT where the Middle Siwalik rocks (Late Miocene) have repeatedly thrust over the Late Pleistocene and Holocene sediments. Presence of large-sized coseismically induced sand-injection feature and its disposition recognized in the trench also suggest occurrence of large magnitude earthquakes in this region. An uplifted and upwarped strath terrace, 3 to 5 m thick alluvium, resting over the 15 m high Middle Siwaliks, abruptly truncated by the HFT indicates its latest activity. Optically Stimulated Luminescence dating techniques were employed to constrain the chronology of events. The long term slip rate of the abandoned terraces due to the activity of the HFT is estimated to be 3.4 mm/yr or greater since Late Holocene. The paleoseismological investigations have provided unambiguous evidences of at least two large magnitude earthquakes occurred in this region where an earthquake with 12 m or larger surface displacement and magnitude 7.5 or greater hit this region in the period between 29.3 ka and 17 ka in the Late Pleistocene and another great earthquake recurred with 20-22 m or more surface displacement and magnitude of 7.7 or greater between 5.8 ka and 2 ka in the Holocene. The present study is the first time report of multiple large magnitude paleoearthquakes in the northwestern part of the Frontal Himalaya during Late Pleistocene and Holocene. The repeated reactivation of HFT substantiates high seismic potential of the Frontal Himalaya and calls for more extensive study of paleoearthquakes of this vastly populous mountainous region.

Philip, G.; Bhakuni, S. S.; Suresh, N.

2012-12-01

168

Natural selection among Kinnaura of the Himalayan highland: A comparative analysis with other Indian and Himalayan populations  

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Full Text Available The present investigation on fertility and mortality differential among Kinnaura of the Himalayan highland is based on data collected from 160 post-menopausal women belonging to the middle and high altitude region of Kinnaur district of Himachal Pradesh (Indian Himalayas. Selection potential based on differential fertility and mortality was computed for middle- and high-altitude women. Irrespective of the methodology, the total index of selection was found to be highest among middle-altitude women (0.386 as compared with high-altitude (0.370 women, whereas for the total population it is estimated to be 0.384. It was found that the Kinnaura of the Himalayan highland showing moderate index of total selection and relative contribution of the mortality component (Im to the index of total selection is higher than the corresponding fertility component (If. The analysis of embryonic and post-natal mortality components shows that the post-natal mortality components are higher in comparison with the embryonic mortality components among highlanders and needs special intervention and health care. The present findings are compared with other Indian tribes as well as non-tribes of the Himalayan region and other parts of the country. It reveals that this index among Kinnaura is moderate than the other population groups; among the Himalayan population, the highest was reported for Galong (It = 1.07 of Arunachal, whereas the lowest was reported from Ahom (It = 0.218 of Manipur. The correlation and regression analysis between total index of selection (It and fertility (If and mortality (Im components for pooled data of populations of the Indian Himalayan states show that If and Im account for 21.6 and 29.1% variability, respectively. In Crow?s total index of selection (It along with strong association, which is significant at the 1% level, this indicates that mortality plays a greater role in natural selection in comparison with fertility among populations of the Indian Himalayas.

Gautam Rajesh

2009-01-01

169

Patagonian red wines: selection of Lactobacillus plantarum isolates as potential starter cultures for malolactic fermentation.  

Science.gov (United States)

The aim of this study was to evaluate fifty-three Lactobacillus plantarum isolates obtained from a Patagonian red wine, molecularly identified and typified using RAPD analysis, in order to select starter cultures for malolactic fermentation (MLF). The results obtained suggest a considerable genetic diversity, taking into account that all L. plantarum isolates were obtained from one cellar and one vintage. Based on the capacity to tolerate a concentration of 14 % ethanol in MRS broth for 2 days, eight isolates were selected for the subsequent analysis. The incidence of various wine stress factors (ethanol, acid pH, lysozyme and sulfur dioxide) on isolates growth was studied. Besides, glucosidase and tannase activities were evaluated, and the presence of genes involved in the synthesis of biogenic amines was examined by PCR. A previously characterized indigenous Oenococcus oeni strain was included with comparative purposes. Differences in technologically relevant characteristics were observed among the eight L. plantarum selected isolates, revealing an isolate-dependent behavior. Detectable glucosidase and tannase activities were found in all isolates. The presence of genes encoding histidine and tyrosine descarboxylases and putrescine carbamoyltransferase was not detected. The ability of L. plantarum isolates to grow and consume L-malic acid in simulated laboratory-scale vinifications revealed that two of them could be considered as possible MLF starter cultures for Patagonian red wines. These isolates will be subjected to further analysis, for a final winery technological characterization. PMID:23546829

Bravo-Ferrada, Bárbara Mercedes; Hollmann, Axel; Delfederico, Lucrecia; Valdés La Hens, Danay; Caballero, Adriana; Semorile, Liliana

2013-09-01

170

A survey of selected pion-nucleus reactions using phase-shift-equivalent potentials  

International Nuclear Information System (INIS)

Since pion-nucleus eleastic scattering data can only constrain the asymptotic behavior of the scattered wave, it remains for inelastic scattering and reaction data to test the wave function in the nuclear interior. To this end, distorted-wave impulse approximation calculations have been performed for a variety of low-energy pion reactions using phase-shift-equivalent pion nucleus potentials: inelastic excitation, photoproduction, and the (?,p) reaction. Sensitivity of the reaction cross sections to variations in the equivalent potentials is examined, with an eye toward understanding what can be learned about pion-nucleus dynamics from a given set of reaction data. (orig.)

171

Recording strategies and selection potential of feed intake measured using the X-ray method in rainbow trout  

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Full Text Available Abstract This study examines the way long-term feed intake should be recorded accurately for selective breeding purposes, and estimates selection potential in feed intake using the X-ray method to record individual daily feed intake in rainbow trout (Oncorhynchus mykiss. The analysis showed that the point estimates of daily feed intake displayed low repeatabilities (r = 0.09–0.32. This indicates that a minimum of three repeated records were needed to accurately record average feed intake at a fixed age. To effectively breed for feed intake over the whole growing period, it is necessary to determine average feed intake at different ages, since there were only moderate phenotypic and genetic correlations between average daily feed intake recorded at 140 g, 750 g and 2000 g wet mass. Heritability for average daily feed intake was low (average h2 = 0.10, indicating that modest genetic changes can be obtained in response to selection. It was concluded that selection to genetically change long-term feed intake can be successful, yet repeated observations at several life stages are needed to ensure the accuracy of feed intake estimates and the efficiency of selection.

Mäntysaari Esa A

2006-06-01

172

Antioxidant potential of selected supplements in vitro and the problem of its extrapolation for in vivo  

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Full Text Available Introduction: antioxidants, free radicals and oxidative stress have been studied extensively for quite some time but their role in diseases and their prevention has not been clearly determined. Because commercialantioxidants do not need to pass clinical tests in order to be sold over the counter we have decided to test the antioxidant potential of different commercial preparations with the antioxidative properties.Methods: pH, rH and oxidant-reduction potential of different preparations in aqueous solution was measured. Afterwards antioxidant potential using FormPlus® after adding the preparation to human blood as a morecomplex environment with different homeostasis mechanisms was determined.Results: all the results showed expected change compared to the control but the results in aqueous solution did not match the results obtained from the human blood, as was expected.Conclusion: from the experiments it can be concluded that while the preparations did show antioxidant activity, it is very difficult and even wrong to predict the antioxidant potential of an antioxidant preparationadded to human blood, let alone in a living organism, based just on the results obtained in aqueous solution. Further possibilities for research include more extensive studies of antioxidant preparations in more complex environment and last but not least in test organisms or in human trials.

Julija Ogrin Papi?

2012-04-01

173

A geostatistical approach to estimation of coal bed methane potentiality in a selected part of Jharia coalfield, Jharkhand  

Energy Technology Data Exchange (ETDEWEB)

In the present study, an integrated geological, statistical, and geostatistical approach to evaluation of CBM potentiality has been attempted in a small part of the Parbatpur block in the Jharia coalfield. The geological study includes preparation of litho logs, their correlation and an understanding of the relationship of various analytical constituents of coal with depth. Statistical and geostatistical modeling of ash, volatile matter and thickness in respect of seam XV reveal the population parameters and spatial characteristics of individual variables. Block-wise CBM potentiality has been assessed by estimating gas-in-place (GIP) for each block. The overall approach to evaluation of the CBM potentiality in the selected part of Jharia coalfield provides an accurate and reliable technique for CBM assessment. The block-by-block CBM estimates thus obtained can be utilized for follow-up decisions in respect of CBM exploitation in the coalfield. 13 refs., 9 figs.

Sarkar, B.C.; Saikia, K.; Sarma, M.; Pandey, S.; Paul, P.R. [Indian School of Mines, Dhanbad (India)

2007-07-01

174

Sensitive and selective determination of molybdenum by flow injection chemiluminescence method combined with controlled potential electrolysis technique  

International Nuclear Information System (INIS)

A sensitive and selective flow injection chemiluminescence (CL) method combined with controlled potential electrolysis technique was described for the determination of molybdenum. The method is based on the chemiluminescence reaction of luminol with unstable molybdenum(III) in alkaline solution. The molybdenum(III) was on-line reduced from molybdenum(VI) via controlled potential electrolysis technique using a homemade flow-through carbon electrolytic cell at the potential of -0.6 V (versus Ag/AgCl). The method allows the determination of molybdenum in the 5.0x10-10 to 5.0x10-7 g ml-1 range with a limit of detection (3?) of 5x10-11 g ml-1 molybdenum. The relative standard deviation is 2.6% for the 1.0x10-9 g ml-1 molybdenum solution in 11 repeated measurements. This method was successfully applied to the determination of molybdenum in water samples

175

Potential productivity and yield gap of selected crops in the rainfed regions of India, Thailand, and Vietnam  

Directory of Open Access Journals (Sweden)

Full Text Available ICRISAT's intervention in the project improving management of natural resources for sustainable rainfed agriculture funded by the Asian Development Bank aims to increase the productivity and sustainability of the medium and high water-holding capacity soils in the intermediate rainfall ecoregion of India, Thailand, and Vietnam. This study examined the potential yield and yield gap of selected crops predominantly grown in the target regions where the project is operational. We used the CROPGRO-soybean model to determine the potential yield and yield gap of soybean crop for several locations in India. For northeastern Thailand and northern Vietnam we compared the experimental yields with the farmers' current yields in the region to estimate the yield gaps. It has been estimated that for several locations in India the soybean yield gap ranged from 19% to 65% of potential yield. For northeastern Thailand the yield gap for paddy rice, upland rice, maize, and soybean ranged from 11% to 67% of their respective potential yields. In northern Vietnam the farmers' maize yields were two-third of the potential yield; however, groundnut and soybean have a yield gap of 40 to 60% of potential yield. Various constraints limiting crop yields in these regions have been highlighted. It is suggested that location-specific integrated approaches would be needed to bridge the yield gap of the predominant crops grown in the target regions.

Piara Singh

2006-08-01

176

Disease burden of fuelwood combustion pollutants in rural households of the Himalayas, India  

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Full Text Available

Background: household biomass combustion for cooking purposes produces pollutants. Exposure to these pollutants has various adverse health impacts and is a major contributor to global disease burden. However, a precise estimate of the burden attributable to biomass combustion at the local level is not available in different parts of the world, therefore restricting policymakers’ ability to develop targeted actions against the health hazards. a study was conducted in the rural Himalayas to generate information about disease burden, with the purpose of aiding the development of strategies to improve public health.
Methods: exposure level, population exposed and other relevant data regarding fuel-wood use, were collected through questionnaire survey from 102 randomly selected households spread in 46 villages in a two phase cluster random sampling design study during 2008 – 09. the burden of disease for acute Lower respiratory Infection (aLrI, chronic obstructive Pulmonary disease (coPd and Lung cancer were estimated as per fuel-based approach of WHo guidelines for rural hilly households, using fuel- wood for cooking.
Results: households, primarily dependent on fuel-wood for fuel, had disability adjusted life years (daLYs lost and deaths that were much higher than the national status. The incidence of disease burden was 2 909 daLYs lost, with a share of 1 987 for aLrI in children "up to" 5 years age, 730 for coPd and 192 for Lung cancer in adults more than 30 years old, respectively.
This result has implications for policy makers when deciding on an effective exposure reduction strategy and describes the risks connected between these health hazards and the health outcome of inhabitants exposed to them. The paper also discusses the intervention strategies for “addressing” the issues relevant to fuel-wood generated exposure.

Rajiv Pandey

2012-03-01

177

Survey on basic knowledge about exposure and potential environmental and health risks for selected nanomaterials  

DEFF Research Database (Denmark)

Based on a literature review this report provides a general description as well as an environmental and health profile of 7 nanomaterials. The examined nanomaterials are selected because of expected high use or specific environmental and health properties. Fullerenes, iron, silver, nanoclay and titanium-, cerium-, and silicondioxides were studied in the project. Based on current uses, it is concluded that current applications of nano-iron and nanoclay can not cause unexpected “nano-associated” health or environmental problems. Although no specific risk associated with current uses of any of the 7 other nanomaterials were identified, there are areas where there may be reason for attention and thus need for more knowledge.

Baun, Anders; Hansen, Steffen Foss

2011-01-01

178

Influence of the heteroatom size on the redox potentials of selected polyoxoanions.  

Science.gov (United States)

The apparent formal potentials for the one-electron redox process of most Keggin-type heteropolytungstates, XW(12)O(40)(q-), have long been shown to linearly depend on their overall negative charges, in the absence of proton interference in the process. However, for a given overall negative charge, these formal potentials are also shown here to depend on the specific central heteroatom X. In the present work, cyclic voltammetry was used to study a large variety of Keggin-type anions, under conditions where their comparisons are straightforward. In short, apparent potential values get more negative (the clusters are more difficult to reduce) for smaller central heteroatoms within a given family of Keggin-type heteropolyanions carrying the same overall negative charge. Density functional theory calculations were performed on the same family of Keggin compounds and satisfactorily reproduce these trends. They show that internal XO(4) units affect differently the tungstate oxide cage. The electrostatic potential created by each internal anionic unit in a fragment-like approach (XO(4)(q-)@W(12)O(36)) was analyzed, and it is observed that X atoms of the same group show slight differences. Within each group of the periodic table, X atoms with lower atomic numbers are also smaller in size. The net effect of such a tendency is to produce a more negative potential in the surroundings and thus a smaller capacity to accept electrons. The case of [BW(12)O(40)](5-) illustrates well this conclusion, with the smallest heteroatom of the Keggin series with group III central elements and a very negative reduction potential with respect to the other elements of the same group. Particularly in this case, the electronic structure of the Keggin anion shows the effects of the small size of boron: the highest occupied molecular orbitals of [BW(12)O(40)](5-) appear to be approximately 0.35 eV higher than those in the other clusters of the same charge, explaining that the BO(4) unit is more unstable than AlO(4) or GaO(4) despite carrying the same formal charge. PMID:20586427

Mbomekallé, Israël-Martyr; López, Xavier; Poblet, Josep M; Sécheresse, Francis; Keita, Bineta; Nadjo, Louis

2010-08-01

179

Psychopathy-Related Differences in Selective Attention Are Captured by an Early Event-Related Potential  

Digital Repository Infrastructure Vision for European Research (DRIVER)

According to the response modulation model, the poorly regulated behavior of psychopathic individuals reflects a problem reallocating attention to process peripheral information while engaged in goal-directed behavior (Patterson & Newman, 1993). We evaluated this tenet using male prisoners and an early event-related potential component (P140) to index attentional processing. In all task conditions, participants viewed and categorized letter stimuli that could also be used to predict electric ...

Baskin–sommers, Arielle; Curtin, John J.; Li, Wen; Newman, Joseph P.

2012-01-01

180

Generation and selection of ribozyme variants with potential application in protein engineering and synthetic biology.  

Science.gov (United States)

Over the past two decades, RNA catalysis has become a major topic of research. On the one hand, naturally occurring ribozymes have been extensively investigated concerning their structure and functional mechanisms. On the other hand, the knowledge gained from these studies has been used to engineer ribozyme variants with novel properties. In addition to RNA engineering by means of rational design, powerful techniques for selection of ribozymes from large pools of random sequences were developed and have been widely used for the generation of functional nucleic acids. RNA as catalyst has been accompanied by DNA, and nowadays a large number of ribozymes and deoxyribozymes are available. The field of ribozyme generation and selection has been extensively reviewed. With respect to the field of biotechnology, RNA and DNA catalysts working on peptides or proteins, or which are designed to control protein synthesis, are of utmost importance and interest. Therefore, in this review, we will focus on engineered nucleic acid catalysts for peptide synthesis and modification as well as for intracellular control of gene expression. PMID:24496571

Balke, Darko; Wichert, Claudia; Appel, Bettina; Müller, Sabine

2014-04-01

 
 
 
 
181

Potential of Mean Force Calculations for Ion Selectivity in a Cyclic Peptide Nanotube  

International Nuclear Information System (INIS)

Ion selectivity in a simple cyclic peptide nanotube, composed of four cyclo[-(D-Ala-Glu-D-Ala-Gln)2-] units, is investigated by calculating the PMF profiles of Na+, K+, and Cl. ions permeating through the peptide nanotube in water. The final PMF profiles of the ions obtained from the umbrella sampling (US) method show an excellent agreement with those from the thermodynamic integration (TI) method. The PMF profiles of Na+ and K+ display free energy wells while the PMF curve of Cl- features free energy barriers, indicating the selectivity of the cyclic peptide nanotube to cations. Decomposition of the total mean force into the contribution from each component in the system is also accomplished by using the TI method. The mean force decomposition profiles of Na+ and K+ demonstrate that the dehydration free energy barriers by water molecules near the channel entrance and inside the channel are completely compensated for by attractive electrostatic interactions between the cations and carbonyl oxygens in the nanotube. In the case of Cl-, the dehydration free energy barriers are not eliminated by an interaction between the anion and the peptide nanotube, leading to the high free energy barriers in the PMF profile. Calculations of the coordination numbers of the ions with oxygen atoms pertaining to either water molecules or carbonyl groups in the peptide nanotube reveal that the stabiliz peptide nanotube reveal that the stabilization of the cations in the midplane regions of the nanotube arises from the favorable interaction of the cations with the negatively charged carbonyl oxygens

182

Neuroactive steroids inhibit spinal reflex potentiation by selectively enhancing specific spinal GABA(A) receptor subtypes.  

Science.gov (United States)

Recently, we demonstrated a spinal GABA(A) receptor (GABA(A)R)-dependent inhibition on the induction of repetitive stimulation-induced spinal reflex potentiation. However, it remains unclear whether steroid hormones modulate such an inhibition. Here, we show that progesterone is capable of producing GABA(A)Rs-dependent inhibition of the induction of spinal reflex potentiation by actions through neurosteroid metabolites. Progesterone (5mg/kg, twice daily for 4 days) up-regulates the expression of GABA(A)R alpha2, alpha3, alpha4 and delta subunits, and is associated with attenuated repetitive stimulation-induced spinal reflex activity in ovariectomized rats. These changes were blocked by finasteride (50mg/kg, twice daily), an antagonist of neurosteroid synthesis from progesterone, but not by the progesterone receptor antagonist, RU486 (100mg/kg, twice daily). The induction of spinal reflex potentiation was attenuated after a short (30 min) intrathecal treatment with the neurosteroids, allopregnanolone (ALLOP, 10 microM, 10 microL) and 3 alpha,5 alpha-tetrahydrodeoxycorticosterone (THDOC, 10 microM, 10 microL). Acute intrathecal administration of the GABA(A)R antagonist, bicuculline (10 microM, 10 microL) reversed the inhibition produced by progesterone, THDOC and allopregnanolone. These results imply that progesterone-mediated effects on GABA(A)R expression and neural inhibition are regulated by neurosteroids synthesis rather than progesterone receptor activation. PMID:19250751

Peng, Hsien-Yu; Chen, Gin-Den; Lee, Shin-Da; Lai, Cheng-Yuan; Chiu, Chun-Hsien; Cheng, Chen-Li; Chang, Yu-Shuo; Hsieh, Ming-Chun; Tung, Kwong-Chung; Lin, Tzer-Bin

2009-05-01

183

The method of assessment of solar potential for selected area with use Geographical Information Systems  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes a method for analyse the spatial distribution of solar energy potential based on calculated solar irradiation with use of GIS (Geographical Information System. Program GIS GRASS gives opportunity to create spatial distribution of solar radiation which is taking into account such important elements like: terrain, atmosphere, pollutants, water and aerosol in atmosphere, clouds. The use of GIS GRASS module – named r.sun gives opportunity to generate spatial distribution of solar radiation on Lower Silesia (south – west part of Poland. In this work the analyse of solar potential to obtain hot water in the individual household were done. This analyse was based on the amount of total solar radiation monthly sums generated by r.sun module. Spatial distribution of solar potential was used to classify the Lower Silesia region in terms of work efficiency solar installations. It is very usefully because it gives people information about the date of the return of the funds invested in the purchase of the solar collectors.

Netzel P.

2012-10-01

184

The method of assessment of solar potential for selected area with use Geographical Information Systems  

Science.gov (United States)

This paper describes a method for analyse the spatial distribution of solar energy potential based on calculated solar irradiation with use of GIS (Geographical Information System). Program GIS GRASS gives opportunity to create spatial distribution of solar radiation which is taking into account such important elements like: terrain, atmosphere, pollutants, water and aerosol in atmosphere, clouds. The use of GIS GRASS module - named r.sun gives opportunity to generate spatial distribution of solar radiation on Lower Silesia (south - west part of Poland). In this work the analyse of solar potential to obtain hot water in the individual household were done. This analyse was based on the amount of total solar radiation monthly sums generated by r.sun module. Spatial distribution of solar potential was used to classify the Lower Silesia region in terms of work efficiency solar installations. It is very usefully because it gives people information about the date of the return of the funds invested in the purchase of the solar collectors.

Pietras, M.; Netzel, P.

2012-10-01

185

Selective nicotinic acetylcholine receptor agonists: potential therapies for neuropsychiatric disorders with cognitive dysfunction.  

Science.gov (United States)

Cognitive impairment is one of the most functionally debilitating aspects of neuropsychiatric and neurodegenerative disorders, such as schizophrenia and Alzheimer's disease, despite treatment with available pharmacotherapies. There is emerging evidence that nicotine improves cognitive function in humans and nonhuman species and this has sparked interest in the development of novel nicotinic treatments for cognitive dysfunction. The examination of selective alpha7 and alpha4beta2 nicotinic acetylcholine receptor (nAChR) agonists suggests that both receptor subtypes mediate improvement in attention, learning and working memory. When compared with available pharmacotherapies, specific nAChR agonists may represent unique targets for the treatment of neuropsychiatric and neurodegenerative disorders that feature cognitive impairment as a key symptom. PMID:18183531

Cincotta, Stephaine L; Yorek, Matthew S; Moschak, Travis M; Lewis, Samantha R; Rodefer, Joshua S

2008-01-01

186

Potential reduction of the ingestion dose after nuclear accidents due to the application of selected countermeasures  

International Nuclear Information System (INIS)

The dynamic food chain model ECOSYS-87 is used to estimate the mitigating effect of selected countermeasures after radioactive contamination of farmland. The considerations focus on the most probably relevant countermeasures in the first 2 years following the accident such as storage of food, food bans, application of derived intervention levels, changes in the processing of foodstuffs, and changes in the feeding regimes of domestic animals. The effectiveness of countermeasures depends on a variety of situation-specific factors which have to be taken into account before any interventions are applied. Such factors are the season during which the deposition occurs, the radionuclide composition of the deposit, and the practicability of the countermeasure in a given situation. (author)

187

Potential reduction of the ingestion dose after nuclear accidents due to the application of selected countermeasures  

Energy Technology Data Exchange (ETDEWEB)

The dynamic food chain model ECOSYS-87 is used to estimate the mitigating effect of selected countermeasures after radioactive contamination of farmland. The considerations focus on the most probably relevant countermeasures in the first 2 years following the accident such as storage of food, food bans, application of derived intervention levels, changes in the processing of foodstuffs, and changes in the feeding regimes of domestic animals. The effectiveness of countermeasures depends on a variety of situation-specific factors which have to be taken into account before any interventions are applied. Such factors are the season during which the deposition occurs, the radionuclide composition of the deposit, and the practicability of the countermeasure in a given situation. (author).

Proehl, G.; Friedland, W.; Mueller, H. (GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Neuherberg (Germany). Inst. fuer Strahlenschutz)

1993-01-01

188

Unbiased descriptor and parameter selection confirms the potential of proteochemometric modelling  

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Full Text Available Abstract Background Proteochemometrics is a new methodology that allows prediction of protein function directly from real interaction measurement data without the need of 3D structure information. Several reported proteochemometric models of ligand-receptor interactions have already yielded significant insights into various forms of bio-molecular interactions. The proteochemometric models are multivariate regression models that predict binding affinity for a particular combination of features of the ligand and protein. Although proteochemometric models have already offered interesting results in various studies, no detailed statistical evaluation of their average predictive power has been performed. In particular, variable subset selection performed to date has always relied on using all available examples, a situation also encountered in microarray gene expression data analysis. Results A methodology for an unbiased evaluation of the predictive power of proteochemometric models was implemented and results from applying it to two of the largest proteochemometric data sets yet reported are presented. A double cross-validation loop procedure is used to estimate the expected performance of a given design method. The unbiased performance estimates (P2 obtained for the data sets that we consider confirm that properly designed single proteochemometric models have useful predictive power, but that a standard design based on cross validation may yield models with quite limited performance. The results also show that different commercial software packages employed for the design of proteochemometric models may yield very different and therefore misleading performance estimates. In addition, the differences in the models obtained in the double CV loop indicate that detailed chemical interpretation of a single proteochemometric model is uncertain when data sets are small. Conclusion The double CV loop employed offer unbiased performance estimates about a given proteochemometric modelling procedure, making it possible to identify cases where the proteochemometric design does not result in useful predictive models. Chemical interpretations of single proteochemometric models are uncertain and should instead be based on all the models selected in the double CV loop employed here.

Wikberg Jarl ES

2005-03-01

189

Visual encoding and fixation target selection in free viewing: presaccadic brain potentials  

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Full Text Available In scrutinizing a scene, the eyes alternate between fixations and saccades. During a fixation, two component processes can be distinguished: visual encoding and selection of the next fixation target. We aimed to distinguish the neural correlates of these processes in the electrical brain activity prior to a saccade onset. Participants viewed color photographs of natural scenes, in preparation for a change detection task. Then, for each participant and each scene we computed an image heat map, with temperature representing the duration and density of fixations. The temperature difference between the start and end points of saccades was taken as a measure of the expected task-relevance of the information concentrated in specific regions of a scene. Visual encoding was evaluated according to whether subsequent change was correctly detected. Saccades with larger temperature difference were more likely to be followed by correct detection than ones with smaller temperature differences. The amplitude of presaccadic activity over anterior brain areas was larger for correct detection than for detection failure. This difference was observed for short “scrutinizing” but not for long “explorative” saccades, suggesting that presaccadic activity reflects top-down saccade guidance. Thus, successful encoding requires local scanning of scene regions which are expected to be task-relevant. Next, we evaluated fixation target selection. Saccades “moving up” in temperature were preceded by presaccadic activity of higher amplitude than those “moving down”. This finding suggests that presaccadic activity reflects attention deployed to the following fixation location. Our findings illustrate how presaccadic activity can elucidate concurrent brain processes related to the immediate goal of planning the next saccade and the larger-scale goal of constructing a robust representation of the visual scene.

AndreyRNikolaev

2013-06-01

190

Neutron scattering studies of methyl derivatives of benzene selected as potential materials for cold neutron moderators  

International Nuclear Information System (INIS)

Vibrational spectra of toluene, m- and p-xylenes and mesitylene, measured by inelastic incoherent neutron scattering at 20 K, are compared. Internal barriers for methyl rotation in free molecules of these compounds are quite low. External barriers caused by crystal packing significantly increase the frequencies of methyl librations in solid p-xylene and the low temperature phase III of mesitylene. The vibrational spectra of glassy states of mesitylene in solution with toluene and m-xylene indicate relatively low barriers for methyl librations and, typical for disordered solids, additional density of states at low frequencies, which makes these materials preferable as potential moderators for cold neutron sources

191

Sporadic, rainfall triggered landslides and debris flows in the monsoon, Nepal Himalaya  

Science.gov (United States)

Small river catchments play a major role in the overall denudation of the Himalayas, because they may generate extreme, geomorphic events. We characterize their potential impacts on the morphology and functioning of trunk rivers, and indirectly on infrastructure and settlements located along the valley floor. Our study case, the Ghatte Khola, is an intermittent tributary of the Kali Gandaki (Western Nepal) affected by occasional debris flow events. The cause of the debris flows is a persistent planar slide zone (dip slope) that is reactivated by pre- or monsoon heavy rainfall on the upper, forested catchment. As a result, the narrow valley of the upstream part of the tributary is temporary clogged by slide masses, until sudden, landslide outburst floods occur. Downstream, where the channel is entrenched across a 5-8 m thick debris fan, the functioning of successive debris flows cause bank erosion and stream channel widening. At the junction with the Kali Gandaki, the flows may aggrade debris volumes large enough to dam the Kali Gandaki for a few hours and cause the level of this major river to rise more than 5 m upstream. During the last 40 years, pulsed aggradations transferred erosion point to the opposite (left bank) side of the Kali Gandaki. This ephemeral, yet threatening behaviour of the stream, occurs every two or three years, according to field investigations (geomorphic mapping, sediment analysis) and interviews of villagers. We present various scenarios simulated using the SAGA-GIS cellular automata combined with a Digital Elevation Model. We discuss the available rainfall intensity-duration thresholds susceptible to trigger Himalayan landslides. Our study suggests that such high-magnitude/low-frequency events are very efficient to foster sediment fluxes and create temporary sediment storages in Himalayan valleys, a fact that is to be considered prior to any new settlement and road design in a country where infrastructures are rapidly developing.

Fort, Monique; Etienne, Cossart; Alexis, Conte; Natacha, Gribenski; Gilles, Arnaud-Fassetta

2010-05-01

192

Uranium estimation in plants of the Siwalik Himalayas, Himachal Pradesh, India  

International Nuclear Information System (INIS)

Fission track technique has been used to estimate uranium content in plants, water and rock samples collected from Siwalik Himalayas of Himachal Pradesh. The present study aims to propose a correlation hypothesis for uranium exploration based on uranium content anomalies. (author)

193

Region-wide glacier mass balances over the Pamir-Karakoram-Himalaya during 1999–2011  

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Full Text Available The recent evolution of Pamir-Karakoram-Himalaya (PKH glaciers, widely acknowledged as valuable high-altitude as well as mid-latitude climatic indicators, remains poorly known. To overcome the lack of region-wide mass balance data, we compared the 2000 Shuttle Radar Topography Mission (SRTM digital elevation model (DEM to recent (2008–2011 DEMs derived from SPOT5 stereo-imagery for 8 sites spread from Pamir to eastern Himalaya. The region-wide glacier mass balances were contrasted during the last decade, with moderate mass losses in eastern and central Himalaya (?0.21 ± 0.10 m yr?1 w.e. to ?0.29 ± 0.09 m yr?1 w.e. and larger losses in western Himalaya (?0.41 ± 0.11 m yr?1 w.e.. Recently reported slight mass gain of glaciers in central Karakoram is confirmed for a larger area (+0.10 ± 0.19 m yr?1 w.e. and, new, also observed for glaciers in western Pamir (+0.14 ± 0.10 m yr?1 w.e.. We propose that the "Karakoram anomaly" should be renamed the "Pamir-Karakoram anomaly", at least for the last decade. The overall mass balance of PKH glaciers is estimated at ?0.12 ± 0.06 m yr?1 w.e. In contrast to Indus, the relative glacier imbalance contribution to Brahmaputra and Ganges discharges is higher than previously modeled glacier seasonal contribution.

J. Gardelle

2013-03-01

194

Use of Indigenous Knowledge in Environmental Decision-Making by Communities in the Kumaon Himalayas  

Science.gov (United States)

This study is designed to find out how people in rural communities residing in the middle Himalayas use indigenous knowledge to support environmental decisions while addressing water and land use related concerns. The study not only serves to enrich our understanding of community decision-making, especially as connected to land use and ecological…

Honwad, Sameer

2010-01-01

195

Tetracladium nainitalense sp. nov., a root endophyte from Kumaun Himalaya, India.  

Science.gov (United States)

An aquatic hyphomycete, Tetracladium nainitalense sp. nov., isolated as a root endophyte from riparian plants from Nainital, Kumaun Himalaya, India, is illustrated and described. The new species is characterized by laterally applanate conidia appearing lobate, with typically four rounded apices and lacking filiform, acicular or subulate elements. An updated key to the species of Tetracladium is provided. PMID:19750949

Sati, S C; Arya, P; Belwal, M

2009-01-01

196

Energy performance contracting - energy saving potential of selected energy conservation measures (ECM)  

Energy Technology Data Exchange (ETDEWEB)

This report has been developed under the research project 'Etablering af grundlag for energitjenester i Danmark' (project number: ENS-33031-0185) under the Danish research programme - EFP. The objective of this project has been to contribute to the utilisation of the large potential for energy conservations in the building sector within the public, industry and service sectors through the development of a better basis for decision making for both the Energy Service Companies (ESCOes) and the building owners. The EU directive on Energy Service Contracting points at the buildings as the area where the biggest potential market for energy services and energy efficiency improvements are. The EFP-project has two parts: (1) A Danish part and (2) participation in the international cooperation project 'Holistic Assesment Tool-Kit on Energy Efficient Retrofit Measures for Government Buildings (EnERGo)', Annex 46 under the IEA R and D program 'Energy Conservation In Buildings And Community Systems' (ECBCS). This report describes the Danish contributions to the IEA projects subtask B, which has a primary objective to develop a database of energy conservation measures (ECM) with descriptions and performance characteristics of these. (au)

Johansson, M. (Dansk Energi Analyse A/S, Frederiksberg (Denmark)); Langkilde, G.; Olesen, Bjarne W. (Technical Univ. of Denmark, ICIEE, Kgs. Lyngby (Denmark)); Moerck, O. (Cenergia Energy Consultants, Herlev (Denmark)); Sundman, O. (DONG Energy, Copenhagen (Denmark)); Engelund Thomsen, K. (Aalborg Univ., SBi, Hoersholm (Denmark))

2008-09-15

197

Potentials of selected metal alloys in sea water at elevated temperatures  

International Nuclear Information System (INIS)

Sixteen metal alloys were studied in aerated sea water at temperatures up to 2000C, and five of these were further studied in deaerated sea water in the same temperature range. Galvanic series are reported for temperatures of 30, 100, 160, and 2000C in an autoclave, and for a trough at ambient conditions. The general effect of increased temperature in both aerated and deaerated sea water was to increase the electronegativity of most metals, and to reduce the spread between the median potential values. At 2000C, the metals merged into two groupings: aluminum and zinc being the most active, other metals were appreciably less negative. In contrast to other metals, zinc and carbon steel showed a tendency toward nobility at higher temperatures. Very small differences were found between the galvanic potentials of most metals in deaerated sea water as compared with these metals in aerated sea water. Titanium appeared to be the exception, being more active in deaerated sea water above 1200C

198

SOIL CARBON DYNAMICS AND GLOBAL WARMING POTENTIAL OF SELECTED SOIL SERIES AND LANDUSE CATEGORIES  

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Full Text Available Land use conversion is usually accompanied by a decline in soil organic carbon. This work is aimed to determine the soil organic carbon affected by the multiple land use in a particular soil series. The study was conducted in Ustic Haplohumults soil series of Kottayam district of Kerala including land uses like Cropland, Wetland, Agricultural land, Homestead and Mixed vegetation land. Change in land use induced significant losses of soil and particulate organic carbon. The maximum SOC content (7.39% was observed in abandoned paddy field which is nearly 89% more than the lowest values of 0.76% recorded from the Homestead soil. Soil carbon sequestration potential of different land uses varies on spatial and temporal basis along with the interplay of environmental externalities. Potential for CO2 production and global warming of various soils was in accordance with C mineralization and this explains the role and capacity of various land use under consideration to store and release carbon. In the present study it was found that the soils of coconut plantation serve as a better system in terms of maximum SOC storage and minimum carbon emission. The present study reveals the significance and importance of specific land use category which is optimal for particular soil series towards soil carbon storage.

Feba Merin Chacko

2014-03-01

199

Do Himalayan glaciers defy global warming? Case studies from NW Himalaya, India  

Science.gov (United States)

The Himalaya is influenced by two major climatic systems that are mid-latitude Westerlies and South Asia Indian Monsoon. The east and south slopes of Himalaya are greatly influenced by the monsoon, whereas the north and west ranges, e.g. Karakorum, have a supply of moisture by mid-latitude Westerlies. The greatest concentration of glaciers occurs in Karakorum Mountains and the western Himalaya which have the longest glaciers outside the polar regions. There is important contrast in the seasonal relationship between precipitation and ablation along the Himalaya. Ladakh and Zanskar hold special geographical significance for the study of climate change, if any. Both the areas lie far away from the effect of South West Indian Monsoon (SWIM) that has largely been identified as the moisture carrier for rest of Himalaya. The moisture laden SWIM bring down the precipitation in the form of snow in most of Himalaya that nourishes the glaciers. On the contrary, the Himalaya in Leh and Zanskar region receive a major contribution of snow through Westerlies during the winter season. Hence, the depletion or growth of glaciers of Leh and Zanskar is related to the weakening or strengthening of Westerlies. The field and satellite imageries study of secular movement of terminus of Durung Drung glacier, Kangriz glacier and Siachen glacier does not reveal any significant retreat. The degeneration of snout could be due to several reasons, such as basin geomorphology, location of glacier on active fault, asynchronous behavior of feeders of the glacier, etc. However, the climate analysis of the area does not point any major change that has affected the health of the glacier in last decade or so.Precipitation in Upper Indus Basin (UIB)is concentrated in winter and spring months that provides principal source for accumulation of UIB glaciers. The climatic data for past four decades of UIB suggest that mean and minimum summer temperatures show cooling and large increase in diurnal temperature range.Reduction in the summer temperatures and positive trend in winter precipitation has resulted in reduced ablation and increased accumulation of Karakorum glaciers. The processes has translated in the expansion and thickening of glaciers that is much contrary to the accepted model of global warming and high glacier melting.

Ganjoo, R. K.

2009-12-01

200

Strong interaction between imidazolium-based polycationic polymer and ferricyanide: toward redox potential regulation for selective in vivo electrochemical measurements.  

Science.gov (United States)

This study effectively demonstrates a strategy to enable the ferricyanide-based second-generation biosensors for selective in vivo measurements of neurochemicals, with glucose as an example. The strategy is based on regulation of redox potential of ferricyanide mediator by carefully controlling the different adsorption ability of ferricyanide (Fe(CN)(6)(3-)) and ferrocyanide (Fe(CN)(6)(4-)) onto electrode surface. To realize the negative shift of the redox potential of Fe(CN)(6)(3-/4-), imidazolium-based polymer (Pim) is synthesized and used as a matrix for surface adsorption of Fe(CN)(6)(3-/4-) due to its stronger interaction with Fe(CN)(6)(3-) than with Fe(CN)(6)(4-). The different adsorption ability of Fe(CN)(6)(3-) and Fe(CN)(6)(4-) onto electrodes modified with a composite of Pim and multiwalled carbon nanotubes (MWNTs) eventually enables the stable surface adsorption of both species to generate integrated biosensors and, more importantly, leads to a negative shift of the redox potential of the surface-confined redox mediator. Using glucose oxidase (GOD) as the model biorecognition units, we demonstrate the validity of the ferricyanide-based second-generation biosensors for selective in vivo neurochemical measurements. We find that the biosensors developed with the strategy demonstrated in this study can be used well as the selective detector for continuous online detection of striatum glucose of guinea pigs, by integration with in vivo microdialysis. This study essentially paves a new avenue to developing electrochemical biosensors effectively for in vivo neurochemical measurements, which is envisaged to be of great importance in understanding the molecular basis of physiological and pathological events. PMID:22263742

Zhuang, Xuming; Wang, Dalei; Lin, Yuqing; Yang, Lifen; Yu, Ping; Jiang, Wei; Mao, Lanqun

2012-02-21

 
 
 
 
201

Renewable energy in Turkey and selected European countries. Potentials, policies and techniques. A handbook  

Energy Technology Data Exchange (ETDEWEB)

One of the major problems encountered in the inclusion of renewable energy in university programmes is the lack of suitable materials and documents which may guide this process. The materials produced as part of the project ''Renewable Energy Networks between Turkish and European Universities'' (RENET) - and this Handbook in particular - will therefore be especially useful to university teachers, since it shows some of the ways via which the subject issue of renewable energy may be included in university programmes. The best-practices here documented also serve the purpose of illustrating how the available know-how can be documented and transferred between countries. By means of this interdisciplinary and inclusive approach, this book will be helpful to universities in Turkey and across Europe, which may want to take full advantage of the potential benefits the inclusion of matters related to renewable energy in university programmes may bring about. (orig.)

Leal Filho, Walter; Mannke, Franziska [Hamburg Univ. of Applied Sciences (Germany). Research and Transfer Centre Applications of Life Sciences; Kuchta, Kerstin; Haker, Konstantin [Hamburg Univ. of Applied Sciences (Germany). Faculty of Life Sciences

2009-07-01

202

Psychopathy-Related Differences in Selective Attention Are Captured by an Early Event-Related Potential  

Science.gov (United States)

According to the response modulation model, the poorly regulated behavior of psychopathic individuals reflects a problem reallocating attention to process peripheral information while engaged in goal-directed behavior (Patterson & Newman, 1993). We evaluated this tenet using male prisoners and an early event-related potential component (P140) to index attentional processing. In all task conditions, participants viewed and categorized letter stimuli that could also be used to predict electric shocks. Instructions focused attention either on the threat-relevant dimension of the letters or an alternative, threat-irrelevant dimension. Offenders with high scores on Hare’s (2003) Psychopathy Checklist-Revised displayed a larger P140 under alternative versus threat conditions. Beyond demonstrating psychopathy-related differences in early attention, these findings suggest that psychopathic individuals find it easier to ignore threat-related distractors when they are peripheral versus central to their goal-directed behavior. PMID:22452763

Baskin-Sommers, Arielle; Curtin, John J.; Li, Wen; Newman, Joseph P.

2012-01-01

203

Phytoremediation potential of Alocasia microrrhiza grown on soil collected from selected dumpsites in Ekiti State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available This study investigates the effect of enhanced phytoextraction on the accumulation of heavy metals by Alocasia microrrhiza cultivated on soil collected from selected dumpsites in Ekiti State, Nigeria. The application of 1g/kg EDTA decreased the heights of plants relative to control, but significantly increased the concentration of heavy metals in various tissues of the plant. Notably, concentration of Pb and Cu were greater than the threshold value of 100mg/kg, indicative of the fact that Alocasia microrrhiza could be a good candidate for Pb and Cuphytoextraction. BF, TF and RR values (1.1–1.6, (4.3-4.8 and (1.4–2.3 revealed the effectiveness of the plant to translocate Pb and Cu to their harvestable portion. RRs values greater than one also indicated the efficiency of plant under chelate-induced phytoextraction. However, the concentration of heavy metals did not vary significantly at p < 0.05 (LSD test in all dumpsites investigated.

Asaolu S. S.

2013-04-01

204

Keynote address: cellular reduction of nitroimidazole drugs: potential for selective chemotherapy and diagnosis of hypoxic cells  

International Nuclear Information System (INIS)

Nitroimidazole drugs were initially developed as selective radiosensitizers of hypoxic cells and, consequently, as adjuvants to improve the local control probabilities of current radiotherapies. Misonidazole (MISO), the prototype radiosensitizing drug, was found in Phase I clinical studies to cause dose-limiting neurotoxicities (mainly peripheral neuropathies). MISO was also found to be cytotoxic in the absence of radiation and to covalently bind to cellular molecules, both processes demonstrating rates much higher in hypoxic compared with oxygenated cells. It is likely that neurotoxicity, cellular cytotoxicity and adduct formation results from reactions between reduction intermediates of MISO and cellular target molecules. Spin-offs from radiosensitizer research include the synthesis and characterization of more potent hypoxic cytotoxins and the exploitation of sensitizer-adducts as probes for measuring cellular and tissue oxygen levels. Current developments in hypoxic cell cytotoxin and hypoxic cell marker research are reviewed with specific examples from studies which characterize the cellular reduction of TF-MISO, (1-(2-nitro-1-imidazolyl)-3[2,2,2-trifluoroethoxy]-2-propanol). 45 references

205

Genotoxic potential of methyleugenol and selected methyleugenol metabolites in cultured Chinese hamster V79 cells.  

Science.gov (United States)

Methyleugenol is a substituted alkenylbenzene classified by the European Union's Scientific Committee on Food as a genotoxic carcinogen. We addressed cytotoxicity, genotoxicity and mutagenicity caused by methyleugenol and selected oxidative methyleugenol metabolites in Chinese hamster lung fibroblasts V79 cells. Cytotoxicity was measured by two cell proliferation assays, water soluble tetrazolium salt (WST) 1 and sulforhodamine B (SRB) assays. Genotoxicity was determined by using single cell gel electrophoreses (comet assay) and the in vitro micronuclei test, while mutagenicity was investigated with the hypoxanthinephosphoribosyl transferase (hprt) assay. Methyleugenol and 1'-hydroxymethyleugenol showed no or marginal cytotoxic effects, but caused DNA strand breaks at concentrations ?10 ?M. The metabolites methyleugenol-2',3'-epoxide and 3'-oxomethylisoeugenol exhibited growth inhibitory properties with IC(50)-values of 70-90 ?M after 48 h or 72 h of incubation. These metabolites significantly enhanced cytotoxicity and DNA damage after 1 h of incubation. Overall, no increase in formamidopyrimidine DNA glycosylase sensitive sites were detected with the comet assay. The metabolites 1'-hydroxymethyleugenol and methyleugenol-2',3'-epoxide exceeded the DNA strand breaking properties of the parent compound methyleugenol. However, only 3'-oxomethylisoeugenol and methyleugenol-2',3'-epoxide induced the formation of micronucleated cells in comparison to the negative control. These compounds were found to be not or rather weakly mutagenic at the hprt locus. In summary, phase I metabolites exceeded the cytotoxic and genotoxic properties of the parent compound methyleugenol. PMID:22302122

Groh, Isabel Anna Maria; Cartus, Alexander Thomas; Vallicotti, Sabrina; Kajzar, Julia; Merz, Karl-Heinz; Schrenk, Dieter; Esselen, Melanie

2012-04-01

206

Antiplasmodial potential of selected medicinal plants from eastern Ghats of South India.  

Science.gov (United States)

Malaria caused by the protozoan parasite Plasmodium falciparum, is a major health problem of the developing world. In the present study medicinal plants from Eastern Ghats of South India have been extracted with ethyl acetate and assayed for growth inhibition of asexual erythrocytic stages of chloroquine (CQ)-sensitive (3D7) and (CQ)-resistant (INDO) strains of P. falciparum in culture using the fluorescence-based SYBR Green I assay. Studied extracts showed a spectrum of antiplasmodial activities ranging from (a) very good (IC(50)10-15 ?g/mL: Ficus religiosa and Murraya koenigii); (c) moderate (IC(50)>15-25 ?g/mL: Ficus benghalensis); (d) poor activity (IC(50)>25-60 ?g/mL) and (e) inactive (IC(50)>60 ?g/mL). Resistance indices ranging from 0.78 to 1.28 suggest that some of these extracts had equal promise against the CQ resistant INDO strain of P. falciparum. Cytotoxicity assessment of the extracts against HeLa cell line using MTT assay revealed that the selectivity indices in the range of 3-15 suggesting a good margin of safety. PMID:23399920

Kaushik, Naveen Kumar; Bagavan, Asokan; Rahuman, Abdul Abdul; Mohanakrishnan, Dinesh; Kamaraj, Chinnaperumal; Elango, Gandhi; Zahir, Abdul Abduz; Sahal, Dinkar

2013-05-01

207

Virulence potential of Enterococcus gallinarum strains isolated from selected Nigerian traditional fermented foods  

Directory of Open Access Journals (Sweden)

Full Text Available Five Enterococcus isolates from some Nigerian traditional fermented foods were identified as Enterococcus gallinarum by using phenotypic and genotypic tests. Safety properties such as antibiotic susceptibility, virulence gene detection, haemolysin, gelatinase and bacteriocin production were determined using standard methods. There was no resistance to clinically relevant antibiotics. Virulence gene for collagen binding antigen and aggregation substance were detected in 60% of the E. gallinarum strains; while surface adhesin was detected in 20%, but none of the strains had cytolysin activator and gelatinase. Phenotype characterizations of the E. gallinarum isolates indicated that none of the isolates produced haemolysin and gelatinase. Enterococcus gallinarum C103 and U82 had no antimicrobial activity against all the selected bacteria pathogens while E. gallinarum W184, T71 and W21 were active against some of the indicator bacteria pathogens. Only E. gallinarum T71 and W21 showed broad spectra of antimicrobial activity. Combination of virulence factors did not appear in these food isolates. Therefore, these strains particularly the two strains with high spectra of antimicrobial activity could be exploited as functional starters in foods.

IYABO C. OLADIPO

2014-08-01

208

Cultivar variation and selection potential relevant to the production of cellulosic ethanol from wheat straw  

DEFF Research Database (Denmark)

Optimizing cellulosic ethanol yield depends strongly on understanding the biological variation of feedstocks. Our objective was to study variation in capacity for producing fermentable sugars from straw of winter wheat cultivars with a high-throughput pretreatment and hydrolysis well-plate technique. This technique enabled us to estimate cultivar-related and environmental correlations between sugar yield, chemical composition, agronomic qualities, and distribution of botanical plant parts of wheat straw cultivars. Straws from 20 cultivars were collected in duplicates on two sites in Denmark. Following hydrothermal pretreatment (180 °C for 17.6 min) and co-hydrolysis, sugar release and sugar conversion were measured. Up to 26% difference in sugar release between cultivars was observed. Sugar release showed negative cultivar correlation with lignin and ash content, whereas sugar release showed positive cultivar correlation with content of carbohydrates and plant height. Accessibility to cellulose can impede thesugar conversion rate, and convertibility of each botanical fraction might be more important to overall sugar conversion than the relative proportions of botanical fractions. Our results suggest that selection of cultivars for improved biofuel feedstock of wheat straw is possible, because heritability of sugar release is 57% and there are few adverse correlations to other agronomic traits.

Lindedam, Jane; Andersen, Sven Bode

2012-01-01

209

A review of the potential and actual sources of pollution to groundwater in selected karst areas in Slovenia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic era prevail. In Slovenia karst groundwater contributes up to 50% of the total drinking water supply. The quality of water is very high, despite the fact that it is extremely vulnerable to pollution. The present article is a study and a review of the potential and actual sources of pollution to the groundwater in the selected karst aquifers (the Kras, Velika planina and Sne?nik plateaus), which diffe...

G. Kova?i?; Ravbar, N.

2005-01-01

210

Mediatorless N(2) incorporated diamond nanowire electrode for selective detection of NADH at stable low oxidation potential.  

Science.gov (United States)

The electrocatalytic properties of a N2 incorporated diamond nanowire (N-DNW) unmodified electrode towards the oxidation of nicotinamide adenine dinucleotide (NADH) was critically evaluated. The electrochemical behavior of the N-DNW unmodified electrode was examined and compared with that of boron-doped diamond, glassy carbon electrode, and graphite electrodes. The N-DNW electrode had high selectivity and high sensitivity for the differential pulse voltammetric detection of NADH in the presence of ascorbic acid at the lower and stable oxidation potential. Moreover, it exhibited strong stability after prolonged usage. The oxidation peak potential at the N-DNW electrode remained unchanged even after exposure to the solution, followed by washing, drying, and storage in laboratory air for 20 days, with minimization of surface contamination. Therefore, the N-DNW unmodified electrode shows promise for the detection of NADH and is attractive for use in a dehydrogenase based biosensor and other analytical applications. PMID:24352298

Shalini, Jayakumar; Sankaran, Kamatchi Jothiramalingam; Chen, Huang-Chin; Lee, Chi-Young; Tai, Nyan-Hwa; Lin, I-Nan

2014-02-21

211

Utilization of the Potentials of Selected Microorganisms as Biocontrol and Biofertilizer for Enhanced Crop Improvement  

Directory of Open Access Journals (Sweden)

Full Text Available Some selected microorganisms isolated from rhizosphere of crops, were screened for their abilities to enhance crop growth and suppress plant parasitic nematodes; in screenhouse experiments. Two promising hybrids of soybean genotypes: TGx 1448-2E (medium duration and TGx 1485-1D (early maturing and a high yielding hybrid of maize genotype Oba Super 1 were used. Microorganisms assessed included the fungi: Trichoderma pseudokoningii, Trichoderma viride, Paecilomyces lilacinus, Aspergillus niger, Glomus mosseae and the rhizobacteria Pseudomonas fluorescens and Pseudomonas putida. One thousand juveniles of Meloidogyne incognita were applied to soybean, while five thousand Pratylenchus zeae (juveniles and adults were applied to maize. Fungal spores and rhizobacteria cells approximately 2.5x106 mL-1 concentration were applied per plant, for maize experiment. For soybean experiment, Bradyrhizobium japonicum (106 cells, Trichoderma pseudokoningii (6.8x106 spores and G. mosseae (200 spores were inoculated per plant. The effect of microorganism`s application was compared with a nematicide (carbofuran treatment, untreated control and a nematode only control. The parameters measured were nematode density, root damage due to plant parasitic nematode infection, relative leaf chlorophyll content and plant growth parameters. The inoculated beneficial microorganisms in most cases significantly (p?0.05 reduced the nematode density across the treatments in test crops by up to 79.6% and improved plant growth by up to 46.0%, when treatments performances were compared across treatments. Most of the beneficial microorganisms assessed have prospects of enhancing nematode management through nematode density reduction and improving crop production.

E.O. Oyekanmi

2008-01-01

212

Phytotoxicity of biosolids and screening of selected plant species with potential for mercury phytoextraction.  

Science.gov (United States)

Mercury contaminated stockpiles of biosolids (3.5-8.4 mg kg(-1) Hg) from Melbourne Water's Western Treatment Plant (MW-WTP) were investigated to evaluate the possibility for their phytoremediation. Nine plant species (Atriplex codonocarpa, Atriplex semibaccata, Austrodanthonia caespitosa, Brassica juncea, Brassica napus, Gypsophila paniculata, Sorghum bicolor, Themeda triandra and Trifolium subterraneum) were screened for phytoextraction potential in Hg-contaminated biosolids from MW-WTP. In addition, the same plant species were germinated and grown in two other substrates (i.e. potting mix and potting mix spiked with mercury(II)). Growth measurements and the mercury uptake for all three substrates were compared. Some plant species grown in potting mix spiked with mercury(II) grew more vigorously than in the other two substrates and showed higher levels of sulphur in their tissues. These results suggested that the mercury stress activated defence mechanisms and it was hypothesised that this was the likely reason for the enhanced production of sulphur compounds in the plant species studied which stimulated their growth. Some species did not grow in biosolids because of the combined effect of high mercury toxicity and high salt content. Atriplex conodocarpa and Australodanthonia caespitose proved to be the most suitable candidates for mercury phytoextraction because of their ability to translocate mercury from roots to the above-ground tissues. PMID:19775810

Lomonte, Cristina; Doronila, Augustine I; Gregory, David; Baker, Alan J M; Kolev, Spas D

2010-01-15

213

Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials  

Science.gov (United States)

New paradigms are required in Brain-Computer Interface (BCI) systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject’s will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP) based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications. PMID:24961765

Cecotti, Hubert; Rivet, Bertrand

2014-01-01

214

Subject Combination and Electrode Selection in Cooperative Brain-Computer Interface Based on Event Related Potentials  

Directory of Open Access Journals (Sweden)

Full Text Available New paradigms are required in Brain-Computer Interface (BCI systems for the needs and expectations of healthy people. To solve this issue, we explore the emerging field of cooperative BCIs, which involves several users in a single BCI system. Contrary to classical BCIs that are dependent on the unique subject’s will, cooperative BCIs are used for problem solving tasks where several people shall be engaged by sharing a common goal. Similarly as combining trials over time improves performance, combining trials across subjects can significantly improve performance compared with when only a single user is involved. Yet, cooperative BCIs may only be used in particular settings, and new paradigms must be proposed to efficiently use this approach. The possible benefits of using several subjects are addressed, and compared with current single-subject BCI paradigms. To show the advantages of a cooperative BCI, we evaluate the performance of combining decisions across subjects with data from an event-related potentials (ERP based experiment where each subject observed the same sequence of visual stimuli. Furthermore, we show that it is possible to achieve a mean AUC superior to 0.95 with 10 subjects and 3 electrodes on each subject, or with 4 subjects and 6 electrodes on each subject. Several emerging challenges and possible applications are proposed to highlight how cooperative BCIs could be efficiently used with current technologies and leverage BCI applications.

Hubert Cecotti

2014-04-01

215

Selection of cyanobacteria isolated from mosquito breeding sites as a potential food source for mosquito larvae.  

Science.gov (United States)

One way to increase the persistence of larvicidal toxins in mosquito breeding sites is to clone the corresponding genes in microorganisms, such as cyanobacteria, which could serve as a source of food for the larvae. We isolated and cultured 10 strains of cyanobacteria from three mosquito breeding sites along the French Mediterranean coast. Most of the strains were tolerant to a relatively wide range of salt concentrations, and all of them were totally or partially resistant to at least four of the five biological or chemical larvicides used in the local mosquito control program. Six unicellular strains from these habitats and Synechococcus strain PCC 7942, a strain maintained for more than 10 years under laboratory conditions, were assessed for ingestion and digestion by larvae Culex pipiens and Anopheles gambiae mosquitoes. The numbers of cells ingested and digested were dependent on the cyanobacterial strain and varied with the mosquito species. Three of the new isolates, Synechococcus strain PCC 8905 and Synechocystis strains PCC 8906 and PCC 8912, were ingested and digested rapidly by larvae of both mosquito species. Since these strains are also tolerant to larvicides and relatively resistant to elevated salt concentrations, they meet the basic requirements for potential recipients of bacterial genes that encode endotoxins. PMID:1677241

Thiery, I; Nicolas, L; Rippka, R; Tandeau de Marsac, N

1991-01-01

216

Antioxidant activity of selected plant species; potential new sources of natural antioxidants.  

Science.gov (United States)

The aim of this study was to examine six plants from Serbia for their potential antioxidant activity. Therefore, six antioxidant activity assays were carried out, including: total antioxidant capacity, DPPH free-radical scavenging, the inhibitory activity toward lipid peroxidation, Fe(3+)- reducing power, Fe(2+)- chelating ability and hydroxyl radical scavenging activity. Total phenolic and flavonoid contents were also determined for each alcoholic extract. Cotinus coggygria extract contained the highest amount of total phenols (413mg GAE /g dry extract), while the highest proportion of flavonoids was found in the Echium vulgare methanol extract (105 mg RU/g). Cotinus coggygria and Halacsya sendtneri alcoholic extracts showed the highest total antioxidant capacity (313 and 231 mg AA/g dry extract), as well as DPPH free-radical scavenging (IC(50)=9 and 99 ?g/ml), inhibitory activity toward lipid peroxidation (IC(50)=3 and 17 ?g/ml) and reducing power. Whereas, the greatest hydroxyl radical scavenging activity, as well as ferrous ion chelating ability showed Echium vulgare, Echium rubrum and Halacsya sendtneri. PMID:20728497

Ni?iforovi?, N; Mihailovi?, V; Maskovi?, P; Soluji?, S; Stojkovi?, A; Pavlovi? Muratspahi?, D

2010-11-01

217

Investigation of greenhouse gas reduction potential and change in technological selection in Indian power sector  

International Nuclear Information System (INIS)

Due to the growing energy needs along with increasing concerns towards control of greenhouse gas emissions, most developing countries are under pressure to find alternative methods for energy conversion and policies to make these technologies economically viable. One of the instruments that have been adopted by many industrial countries is that of the carbon tax. The rate of introducing carbon taxes however, depends upon the local economic conditions and market forces. The case of Indian power sector has been examined by using MARKAL model for introduction of carbon taxes at four different trajectories. Their implications on the power generation choices have been investigated for a time span of 25 years from the year 2000. In general large hydropower plants have emerged as the first choice followed by wind energy systems. However, cheaper availability of coal in India keeps scope of use of coal based technologies for which pressurised fluidised bed combustion technology has been found to be the balanced choice among fossil technologies. There exists a potential of reduction of greenhouse gas emissions by about 25% as compared to the 'business-as-usual' case in presence of high carbon tax rates

218

Selection of potential cold water marine species for testing of oil dispersants, and chemically dispersed oil  

International Nuclear Information System (INIS)

A study regarding marine species for toxicity testing for Alaska conditions was presented and the potential adverse impacts of a large marine oil spill in cold water were discussed with the objective to determine if the spill should be treated by the use of oil dispersants. Without dispersion, the oil can pollute marine epifauna and can deposit on beaches. The decision to apply dispersants to a marine oil spill requires knowledge of the toxicity of the undispersed oil to pelagic marine life occurring via natural dispersion as opposed to the toxicity of the oil-dispersant mixture. Most standard toxicity tests apply to warm water species. This paper discussed the need to have a standard test species relevant to Alaska waters for toxicity testing. In this study, toxicity testing was done according to the methods of the Chemical Response to Oil Spills : Ecological Effects Research Forum (CROSERF). The testing included capturing adult species in the winter and holding them until larval hatching. Toxicity testing was completed in a narrow time frame before hatching ceased. Many chemical samples were tested. Topsmelt, urchins, shellfish, mysids, copepods, pink salmon fry, and tidepool sculpin were considered by the author to be the most useful for certain types of toxicity testing. 29 refs

219

CCT241533 is a potent and selective inhibitor of CHK2 that potentiates the cytotoxicity of PARP inhibitors.  

Science.gov (United States)

CHK2 is a checkpoint kinase involved in the ATM-mediated response to double-strand DNA breaks. Its potential as a drug target is still unclear, but inhibitors of CHK2 may increase the efficacy of genotoxic cancer therapies in a p53 mutant background by eliminating one of the checkpoints or DNA repair pathways contributing to cellular resistance. We report here the identification and characterization of a novel CHK2 kinase inhibitor, CCT241533. X-ray crystallography confirmed that CCT241533 bound to CHK2 in the ATP pocket. This compound inhibits CHK2 with an IC(50) of 3 nmol/L and shows minimal cross-reactivity against a panel of kinases at 1 ?mol/L. CCT241533 blocked CHK2 activity in human tumor cell lines in response to DNA damage, as shown by inhibition of CHK2 autophosphorylation at S516, band shift mobility changes, and HDMX degradation. CCT241533 did not potentiate the cytotoxicity of a selection of genotoxic agents in several cell lines. However, this compound significantly potentiates the cytotoxicity of two structurally distinct PARP inhibitors. Clear induction of the pS516 CHK2 signal was seen with a PARP inhibitor alone, and this activation was abolished by CCT241533, implying that the potentiation of PARP inhibitor cell killing by CCT241533 was due to inhibition of CHK2. Consequently, our findings imply that CHK2 inhibitors may exert therapeutic activity in combination with PARP inhibitors. PMID:21239475

Anderson, Victoria E; Walton, Michael I; Eve, Paul D; Boxall, Katherine J; Antoni, Laurent; Caldwell, John J; Aherne, Wynne; Pearl, Laurence H; Oliver, Antony W; Collins, Ian; Garrett, Michelle D

2011-01-15

220

[Selection of winter plant species for wetlands constructed as sewage treatment systems and evaluation of their wastewater purification potentials].  

Science.gov (United States)

In order to establish an evaluation system for selection of winter wetland plants possessing high wastewater purification potentials in subtropics areas, designed sewage treatment experiments were carried out by introducing into the constructed wetlands 25 species of winter wetland plants. Cluster analysis was performed by including harmful environment-resistant enzyme and substrate enzyme activities into the commonly applied plant screening and assessment indexes system. The obtained results indicated that there were significant differences among the tested winter plants in their root length and vigor, leaf malonaldehyde (MDA), biomass, average nitrogen and phosphorus concentration and uptake, and urease and phosphoric acid enzyme activities in the root areas. Based on the established evaluation system, the tested plants were clustered into 3 groups. The plants in the 1st group possessing high purification potentials are Oenanthe javanica, Brassicacapestris, Juncus effusu, Saxifragaceae, Iris pseudoacorus, Osmanthus fragrans and Iris ensata; those in the 2nd group possessing moderate purification potentials are Brassica oleracea var acephala, Calendula officinalis, Aucuba japonica, Ligustrum lucidu, Beta vulgaris, Rhododendron simsii and Ilex latifolia; and those in the 3rd group with low purification potentials are Brassica oleracea var acephala, Calistephus chinensis, Rosa chinensis, Antirrhinums, Liriope palatyphylla, Zephyranthes candida, Fatshedera lizei, Petunia hybrida, Ilex quihoui, Dianthus caryophyllus and Loropetalum chinensis. PMID:21090294

Chen, Yong-hua; Wu, Xiao-fu; Chen, Ming-li; Jiang, Li-juan; Li, Ke-lin; Lei, Dian; Wang, Hai-bin

2010-08-01

 
 
 
 
221

[Selection and purification potential evaluation of woody plant in vertical flow constructed wetlands in the subtropical area].  

Science.gov (United States)

In order to solve the problem that wetland herbaceous plants tend to die during winter in subtropics areas, selection and purification potential evaluation experiments were carried out by introducing into the constructed wetlands 16 species of woody wetland plants. Cluster analysis was performed by including the morphological characteristics, physiological characteristics, as well as nitrogen and phosphorus accumulation of the woody wetland plants. The results indicated that there were significant differences among the tested woody plants in their survival rate, height increase, root length increase and vigor, Chlorophyll content, Superoxide dismutase, Malonaldehyde, Proline, Peroxidase, biomass, average concentration and accumulation of nitrogen and phosphorus. Based on the established evaluation system, the tested plants were clustered into 3 groups. The plants in the 1st group possessing high purification potentials are Nerium oleander and Hibiscus syriacus. Those in the 2nd group possessing moderate purification potentials are Trachycarpus fortune, Llex latifolia Thunb., Gardenia jasminoides, Serissa foetida and Ilex crenatacv Convexa. And those in the 3rd group with low purification potentials are Jasminum udiflorum, Hedera helix, Ligustrum vicaryi, Ligustrum lucidum, Buxus sempervives, Murraya paniculata, Osmanthus fragrans, Mahoniafortune and Photinia serrulata. PMID:24812951

Chen, Yong-Hua; Wu, Xiao-Fu; Hao, Jun; Chen, Ming-Li; Zhu, Guang-Yu

2014-02-01

222

Out-of-Sequence Thrust in the Higher Himalaya- a Review & Possible Genesis  

Science.gov (United States)

An out-of-sequence thrust (OOST) has been established inside the Higher Himalaya by previous workers more frequently from Nepal- and Bhutan Himalaya. The OOST lies between the South Tibetan Detachment System-Upper (STDSU) and the South Tibetan Detachment System-Lower (STDSL). The thrust has been recognized as the Kakhtang Thrust in Bhutan (Grujic et al., 2002 and references therein); Khumbu Thrust (Searle, 1999), Modi Khola Shear Zone (Hodges et al., 1996), Kalopani Shear Zone (Vannay and Hodges, 1999), Toijem Shear Zone in Nepal (Carosi et al., 2007), Chaura Thrust (Jain et al., 2000)- also designated as the Sarahan Thrust (Chambers et al., 2008) in the western Indian Himalaya in Sutlej section, Zimithang Thrust in the eastern Indian Himalaya (Yin et al., 2006), as ‘physiographic transition' in Marsyandi valley, Nepal (Burbank et al., 2003). We note that considering the upper strand of the Main Central Thrust (the MCTU) as the lower boundary of the Higher Himalaya, the physiographic transition has also been referred to lie in the Lesser Himalaya.The period of activity of the OOST was 22.5-18.5 Ma (Hodges et al., 1996), 14-10 Ma (Grujic et al., 2002), 4.9-1.5 Ma (Jain et al., 2000), and from Late Pliocene to even Holocene Period (Burbank, 2005). The out-of-sequence thrusting was followed after the initiation of channel flow at ~ 15 Ma in the Higher Himalaya with a maximum delay of ~ 13 Ma. However, in the Bhutan Himalaya, the thrusting continued along with the extensional ductile shearing in the STDSU at 11-10 Ma (Hollister and Grujic, 2006). The OOST in the Higher Himalaya lies inside the zone of the top-to-SW sense of ductile shearing. The OOST, at Kakhtang, Toijem, and Chaura are ductile shear zones with a top-to-SW sense of shearing. The OOST merges with the MCT and the Main Himalayan Thrust (MHT) at a depth of 30 km or more and either runs 200-300 km beneath the Tibetan plateau (Grujic et al., 2002; Hollister and Grujic, 2006). The hanging wall side of the OOST is more dominant with migmatites and leucogranites (Searle, 1999; Yin et al., 2006; Carosi et al., 2007; Grujic et al., 2002; Hollister and Grujic, 2006), but the footwall side does contain these rocks (Hodges et al., 1996; Chambers et al., 2008). The thickness of the OOST are 50 m (Carosi et al., 2007), >150 m (Yin et al., 2006), 3-6 km (Searle, 1999) and ~ 1.5 km (Vannay and Hodges, 1996). A number of hypotheses have been put forward to explain the genesis of the OOST. These are (i) a disparity in erosion rates triggered mainly by a spatial variation in the intensity of rainfall (Wobus et al., 2005). (ii) The lower boundary of the channel flow extrusion defined the OOST (Hollister and Grujic, 2006). (iii) As a result of a heterogeneous velocity profile of channel flow extrusion across lithologic discontinuity (Carosi et al., 2007). The granitic melt at depth in some way led to this thrusting (Swapp and Hollister, 1991). Had channel flow been the extrusion mechanism of the Higher Himalaya, the genesis of the OOST might somehow be related to this extrusion. In this work, a channel flow box was prepared and polydimethylsiloxane was used as the model material. A channel flow was generated in the horizontal channel and was allowed to extrude through an inclined channel similar to the Higher Himalaya (Mukherjee, 2007). In different considerations, the walls of the Higher Himalaya are parallel and diverging-up. A late formed blind thrust plane forms at the corner joining the inclined and the horizontal wall and crops to the surface much later to the initiation of channel flow. On the basis of its late arrival to the surface than the channel flow and its relative position in the model Higher Himalaya, the thrust is comparable with the OOST. This means that (i) climatic factors nor lithologic discontinuity were a trigger to the OOST; and (ii) the OOST is a delayed product of channel flow that initiated at a sub-horizontal channel below the Tibetan plateau and extrude the Higher Himalaya. References. Burbank, D.W., 2005. Cracking the Himalaya. Nature 434, 963-9

Mukherjee, S.; Koyi, H. A.; Talbot, C. J.

2009-04-01

223

Seleção de plantas com potencial para fitorremediação de tebuthiuron Plant selection with potential for tebuthiuron phytodecontamination  

Directory of Open Access Journals (Sweden)

Full Text Available Este trabalho teve como objetivo selecionar espécies tolerantes ao tebuthiuron, visando utilizá-las em programas de fitorremediação de solos contaminados com esse herbicida. Foram avaliadas: Amaranthus hybridus, Crotalaria juncea, Chamaesyce hyssopifolia, C. hirta, Canavalia ensiformes, Helianthus annus, Pennisetum typhoides, Estizolobium aterrimum, Raphanus raphanistrum e Crotalaria incana. O experimento foi conduzido em casa de vegetação, em vasos contendo 3 dm³ de solo de textura argilo-arenosa com 2,18 dag kg¹ de matéria orgânica. O experimento foi delineado em blocos ao acaso, com três repetições de tratamentos em fatorial 10 x 4 x 4, os quais foram constituídos por 10 espécies, quatro doses de tebuthiuron (0,0; 5,0; 1,0; e 2,0 kg ha-1, aplicadas em pré-emergência, e quatro épocas de avaliação (15, 30, 45 e 60 dias após a semeadura. Foram avaliadas a fitotoxicidade do herbicida, a altura de plantas e a massa de matéria seca da parte aérea, de raízes e do total da planta. Canavalia ensiformes e Pennisetum typhoides foram tolerantes ao tebuthiuron na dose de 0,5 kg ha-1. Estizolobium aterrimum tolerou tebuthiuron até a dose de 1,0 kg ha¹, apresentando fitotoxicidade menos acentuada e menor redução de altura de plantas e da massa de matéria seca da parte aérea, de raízes e do total da planta em relação ao tratamento testemunha.This study aimed to select tebuthiuron- tolerant plants to use them in phytoremediation programs in contaminated soils. The evaluated species were: Amaranthus hybridus, Crotalaria juncea, C. hyssopifolia, Chamaesyce hirta, Canavalia ensiformes, Helianthus annus, Pennisetum typhoides, Estizolobium aterrimum, Raphanus raphanistrum and Crotalaria incana. The experiment was carried out in a greenhouse, with a sandy-clay soil with 2.18 dag kg-1 of organic matter, in pots of 3 dm³ capacity. The experiment was arranged in a 10 x 4 x 4 factorial scheme in a randomized block design with three replications. The treatments consisted of: 10 species, four tebuthiuron doses (0.0; 0.5; 1.0 e 2.0 kg ha-1 applied in pre-emergence, and four evaluation times (15, 30, 45, and 60 days after sowing. Phytotoxicity, plant height and, above-ground, root and total biomass dry matter were evaluated. Canavalia ensiformes and Pennisetum typhoides were tolerant to tebuthiuron at the dose of 0.5 kg ha-1, and Estizolobium aterrimum up to the dose of 1.0 kg ha-1, with the latter showing less phytotoxicity symptoms and a smaller reduction of plant height, above-ground, root, and total biomass dry matter, as compared to the control treatment.

F.R. Pires

2003-12-01

224

The potential use of an alternative fluid for SFR intermediate loops: selection and first design  

International Nuclear Information System (INIS)

Among the Generation IV systems, Sodium Fast Reactors (SFR) are promising and benefit of considerable technological experience, but improvements are researched on safety approach and capital cost reduction. One of the main problems to be solved by the standard SFR design is the proper management of the risk of leakage between the intermediate circuit filled with sodium and the energy conversion system using a water Rankine cycle. This risk requires notably an early detection of water leakage to prevent a water-sodium reaction. One innovative solution to this problem is the replacement of the sodium in the secondary loops by an alternative liquid fluid, less reactive with water. This alternative fluid might also allow innovative designs, e.g. intermediate heat exchanger and steam generator grouped in the same component. CEA, Areva NP and EdF have formed a working group in order to evaluate different 'alternative fluids' that might replace sodium. A first selection retained seven fluids on the bases of 'required properties' as: large operating range (low melting point, high boiling point ...), fluid cost and availability, acceptable corrosion at SFR working temperature. These are three bismuth alloys, two nitrate salts, one hydroxide melt and sodium with nanoparticles. Then, it was decided to evaluate these fluids through a multi- criteria analysis in order to point advantages and drawbacks of each fluid and to compare them with sodium. Lack of knowledge, impact on mate sodium. Lack of knowledge, impact on materials, design, working conditions and reactor availability should be emphasized by this analysis, in order to provide sound arguments for a research program on one or two most promising fluids. A global note is given to each fluid by evaluating them with respect to 'grand criteria', weighted differently according to their importance. The grand criteria were: thermal properties, reactivity with structures, reactivity with other fluids (air, water, sodium), chemistry control (including tritium management), safety and waste management, inspection maintenance and repair (ISI and R), impact on components and circuits, availability and cost, level of use. The impact on reactor availability and manageability and the level of knowledge on each fluid were estimated through the former criteria and introduced in the final evaluation as main criteria. The aim of this paper is to present the method of evaluation, the results obtained and the choice that have been made. The impact on design and operation are enhanced for the most promising fluids. It was found that sodium remains the most interesting intermediate fluid. However, Lead Bismuth Eutectic and sodium with nanoparticles also presents some interests and should be further evaluated. (author)

225

Minor soil erosion contribution to denudation in Central Nepal Himalaya.  

Science.gov (United States)

In order to decipher river sediments provenance in terms of erosion processes, we characterized geochemical compositions of hillslope material coming from soils, glaciers and landslide, and compared them to rivers sediments. We focused our study on two South flank Himalayan catchments: (1) Khudi khola, as an example of small High Himalayan catchment (150 km2), undergoing severe precipitation, and rapid erosion ? 3.5 mm/yr [A] and (2) the Narayani-Gandak Transhimalayan basin (52000 km2) that drains the whole central Nepal. To assess the question, systematic samplings were conducted on hillslope material from different erosion processes in the basins. River sediment include daily sampling during the 2010 monsoon at two stations, and banks samples in different parts of the basins. Source rocks, soil and landslide samples, are compared to river sediment mobile to immobile element ratios, completed by hydration degree H2O+ analysis[2]. Data show that soils are clearly depleted in mobile elements Na, K, Ca, and highly hydrated compared to source rocks and other erosion products. In the Khudi basin, the contrast between soil and river sediment signatures allow to estimate that soil erosion represents less than 5% of the total sediment exported by the river. Most of the river sediment therefore derives from landslides inputs and to a lesser extent by barren high elevation sub-basins. This is further consistent with direct observation that, during monsoon, significant tributaries of the Khudi river do not export sediments. Considering that active landslide zones represent less than 0.5% of the total watershed area, it implies that erosion distribution is highly heterogeneous. Landslide erosion rate could reach more than 50 cm/yr in the landslide area. Sediments of the Narayani river are not significantly different from those of the Khudi in spite of more diverse geomorphology and larger area of the basin. Only H2O+ and Total Organic Carbon concentrations normalised to Al/Si ratios show distinctly higher values. This suggests that contribution of soil erosion is higher than in the Khudi basin. Nevertheless, soil erosion remains a minor source of sediments implying that more physical processes such as landslide and glaciers dominate the erosional flux. In spite of high deforestation and agricultural land-use [B], soil erosion does not represent an important source of sediments in Nepal Himalaya. [A] Gabet et al. (2008) Earth and Planetary Science Letters 267, 482-494. [B] Gardner et al. (2003) Applied Geography 23, 23-45.

Morin, Guillaume; France-Lanord, Christian; Gallo, Florian; Lupker, Maarten; Lavé, Jérôme; Gajurel, Ananta

2013-04-01

226

A method for selecting potential geosites. The case of glacial geosites in the Chablais area (French and Swiss Prealps)  

Science.gov (United States)

Since 2009, an Interreg IVA project (123 Chablais), dealing with the promotion of natural and cultural heritage in the Chablais area, has been developed. It is linked to the creation of the Chablais Geopark. In a context of development of smart forms of tourism, the objective was to develop a strategy promoting the glacial heritage to a wide public in an area where the glaciers have almost disappeared. The recognition of specific places as geoheritage is the result of a double process: a scientific one, based on more or less sophisticated methods, and a social one, that is the acknowledgment by the society. One of the first scientific tasks is to produce a list of "potential geosites" that will be assessed in more details. However, this selection is often a weak point of inventories. It often seems like a "black box" without any transparency. In this project (123 Chablais) we carried out an inventory of glacial geosites, using the method developed by Reynard et al. (2007, 2012). However, a method has been created to enlighten the selection process, and to enhance choices in geoheritage management. As it was not possible to consider all sites in the Chablais area, a mixed selection approach was developed, halfway between completeness and specificity (Martin, 2012). The first step was the creation of a list of "points of interest", established using different sources: literature review, fieldwork and use of GIS to cross information. A selection was then performed according to two criteria: correspondence with a glacial stage (time axis) and belonging to a type of forms (spatial axis). Finally, selected sites aimed at providing a representative overview of the regional glacial witnesses. Therefore, representative sites of the regional geology were selected as well as sites presenting regional peculiarities Temporal and spatial attributes were given to the 101 points of interest identified. From a temporal point of view, this inventory aimed at presenting the main stages of the glacial retreat since the Last Glacial Maximum. From a spatial point of view, the objective was to show the different types of glacial remnants, but also some landforms related to deglaciation processes. Finally, 32 glacial and associated geosites were selected. Each geosite was submitted to a full evaluation process, including basis information, description, explanation of morphogenesis and an evaluation of values assigned to geosites. This assessment, first qualitative, provided valuable information concerning their intrinsic interest and their management. A numerical evaluation was also assessed to classify geosites and define an order of priority for their touristic promotion. It is worth to be noted that each selected points of interest can in fact be qualified as a geosite, using a clear method of selection. In this study, the numerical evaluation is not a mean to select geosites but a way to rank one geosite to another. Some geosites can be abandoned if intrinsic values are too low. Despite a well-defined protocol, the subjectivity and authors' choices are part of the selection process and inventory. This fact is certainly not a weakness. It must be considered whenever such inventory is made. Reference Martin, S. (2012). Valoriser le géopatrimoine par la médiation indirecte et la visualisation des objets géomorphologiques (Thèse de doctorat). Université de Lausanne, Lausanne. Reynard E., Fontana G., Kozlik L., Scapozza C. (2007). A method for assessing the scientific and additional values of geomorphosites, Geographica Helvetica, 62(3), 148-158. Reynard, E., Perret, A., Grangier, L., & Kozlik, L. (2012). Methodological approach for the assessment, protection, promotion and management of geoheritage. EGU General Assembly, Vienna.

Perret, Amandine; Reynard, Emmanuel

2014-05-01

227

Marker-assisted selection as a potential tool for genetic improvement in developing countries: debating the issues  

International Nuclear Information System (INIS)

Marker-assisted selection (MAS) is a complementary technology, for use in conjunction with more established conventional methods of genetic selection, for plant and animal improvement. It has generated a good deal of expectations, many of which have yet to be realized. Although documentation is limited, the current impact of MAS on products delivered to farmers seems small. While the future possibilities and potential impacts of MAS are considerable, there are also obstacles to its use, particularly in developing countries. Principal among these are issues relating to current high costs of the technology and its appropriateness, given that publicly funded agricultural research in many developing countries is suboptimal and development priorities do not necessarily include genetic improvement programmes. Other potential obstacles to the uptake of MAS in developing countries include limited infrastructure, the absence of conventional selection and breeding programmes, poor private sector involvement and lack of research on specific crops of importance in developing countries. Intellectual property rights may also be an important constraint to development and uptake of MAS in the developing world. It is hoped that through partnerships between developing and developed country institutions and individuals, including public-private sector collaboration, MAS costs can be reduced, resources pooled and shared and capacity developed. With the assistance of the Consultative Grouth the assistance of the Consultative Group on International Agricultural Research (CGIAR) and international organizations such as FAO, developing countries can benefit more from MAS. These were some of the outcomes of a moderated e-mail conference, entitled 'Molecular Marker- Assisted Selection as a Potential Tool for Genetic Improvement of Crops, Forest Trees, Livestock and Fish in Developing Countries', that FAO hosted at the end of 2003. During the four-week conference, 627 people subscribed and 85 messages were posted, about 60 percent coming from people living in developing countries. Most messages (88 percent) came from people working in research centres (national or international) or universities. The remainder came from people working as independent consultants or from farmer organizations, government agencies, non-governmental organizations (NGOs) or United Nations (UN) organizations. (author)

228

Discovery of potential and selective COX-1 inhibitory leads using pharmacophore modelling, in silico screening and in vitro evaluation.  

Science.gov (United States)

Cyclooxygenase -1 (COX-1) selective inhibitors are anticipated to be potential therapeutic agents for thrombosis, tumorigenesis, atherosclerosis, neuroprotection, and oxidative stress. In this study, a 3D-QSAR pharmacophore model was developed for potent and selective COX-1 inhibition based on 44 compounds from four different scaffolds using Phase, Schrödinger. One (hydrogen-bond) acceptor, one hydrophobic, and two aromatic sites (AHRR) contribute to COX-1 inhibitory activity. Test and decoy sets were used to corroborate the best hypothesis and the validated hypothesis was used to screen the SPECS database. The resultant hits were filtered by standard precision (SP) and extra precision (XP) modes of docking using Glide, Schrödinger which yielded five hits. Free energy calculations were carried out to quantify the affinity differences of the hits towards COX enzymes. These five hits were subjected to in vitro COX (ovine) inhibitory activity studies. The hits displayed potent COX-1 inhibitory activity and good selectivity versus COX-2 enzyme. The compounds also protected the nitric oxide (NO) induced cell death mediated by COX-1 in mouse macrophages cell line. Hence, we hypothesize that these compounds could be promising leads for the design of superior COX-1 inhibitors and insights gained from further exploration of the same could provide pertinent clues for the treatment of the conditions mentioned above. PMID:25203777

Balaji, Bhaskar; Hariharan, Sivaram; Shah, Darshit B; Ramanathan, Muthiah

2014-10-30

229

Structural differences of matrix metalloproteinases with potential implications for inhibitor selectivity examined by the GRID/CPCA approach  

DEFF Research Database (Denmark)

The matrix metalloproteinases (MMPs) are a family of proteolytic enzymes, which have been the focus of a lot of research in recent years because of their involvement in various disease conditions. In this study, structures of 10 enzymes (MMP1, MMP2, MMP3, MMP7, MMP8, MMP9, MMP12, MMP13, MMP14, and MMP20) were examined with the intention of highlighting regions that could be potential sites for obtaining selectivity. For this purpose, the GRID/CPCA approach as implemented in GOLPE was used. Counterions were included to take into account the different electrostatic properties of the proteins, and the GRID calculations were performed, allowing the protein side chains to move in response to interaction with the probes. In the search for selectivity, the MMPs are known to be a very difficult case because the enzymes of this family are very similar. The well-known differences in the S1' pocket were observed, but in addition, the pockets S3 and S2 called for attention. This is an observation that emphasizes the needfor design of inhibitors exploiting the unprimed side of the active site, if possible, in combination with the S1' site. Despite small differences, a rational usage of the findings described in this work should make it possible to use a combination of the features of the individual enzyme pockets, making most of the MMP enzymes possible targets for selective inhibition. The results suggest the possibility of distinguishing between 8 of the 10 enzymes by this approach.

Terp, Gitte Elgaard; Cruciani, Gabriele

2002-01-01

230

Selection pressures have caused genome-wide population differentiation of Anthoxanthum odoratum despite the potential for high gene flow.  

Science.gov (United States)

The extent to which divergent selection can drive genome-wide population differentiation remains unclear. Theory predicts that in the face of ongoing gene flow, population differentiation should be apparent only at those markers that are directly or indirectly (i.e. through linkage) under selection. However, if reproductive barriers limit gene flow, genome-wide population differentiation may occur even in geographically proximate populations. Some insight into the link between selection and genetic differentiation in the presence of ongoing gene flow can come from long-term experiments such as The Park Grass Experiment, which has been running for over 150 years, and provides a unique example of a heterogeneous environment with a long and detailed history. Fertilizer treatments applied in the Park Grass Experiment have led to rapid evolutionary change in sweet vernal grass Anthoxanthum odoratum, but until now, nothing was known of how these changes would be reflected in neutral molecular markers. We have genotyped ten A. odoratum populations from the Park Grass Experiment using Amplified Fragment Length Polymorphisms (AFLPs). Our data show that nutrient additions have resulted in genome-wide divergence among plots despite the high potential for ongoing gene flow. This provides a well-documented example of concordance between genomes and environmental conditions that has arisen in continuous populations across a time span of fewer than 75 generations. PMID:20163507

Freeland, J R; Biss, P; Conrad, K F; Silvertown, J

2010-04-01

231

Seleção de plantas com potencial para fitorremediação de tebuthiuron / Plant selection with potential for tebuthiuron phytodecontamination  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho teve como objetivo selecionar espécies tolerantes ao tebuthiuron, visando utilizá-las em programas de fitorremediação de solos contaminados com esse herbicida. Foram avaliadas: Amaranthus hybridus, Crotalaria juncea, Chamaesyce hyssopifolia, C. hirta, Canavalia ensiformes, Helianthus a [...] nnus, Pennisetum typhoides, Estizolobium aterrimum, Raphanus raphanistrum e Crotalaria incana. O experimento foi conduzido em casa de vegetação, em vasos contendo 3 dm³ de solo de textura argilo-arenosa com 2,18 dag kg¹ de matéria orgânica. O experimento foi delineado em blocos ao acaso, com três repetições de tratamentos em fatorial 10 x 4 x 4, os quais foram constituídos por 10 espécies, quatro doses de tebuthiuron (0,0; 5,0; 1,0; e 2,0 kg ha-1), aplicadas em pré-emergência, e quatro épocas de avaliação (15, 30, 45 e 60 dias após a semeadura). Foram avaliadas a fitotoxicidade do herbicida, a altura de plantas e a massa de matéria seca da parte aérea, de raízes e do total da planta. Canavalia ensiformes e Pennisetum typhoides foram tolerantes ao tebuthiuron na dose de 0,5 kg ha-1. Estizolobium aterrimum tolerou tebuthiuron até a dose de 1,0 kg ha¹, apresentando fitotoxicidade menos acentuada e menor redução de altura de plantas e da massa de matéria seca da parte aérea, de raízes e do total da planta em relação ao tratamento testemunha. Abstract in english This study aimed to select tebuthiuron- tolerant plants to use them in phytoremediation programs in contaminated soils. The evaluated species were: Amaranthus hybridus, Crotalaria juncea, C. hyssopifolia, Chamaesyce hirta, Canavalia ensiformes, Helianthus annus, Pennisetum typhoides, Estizolobium at [...] errimum, Raphanus raphanistrum and Crotalaria incana. The experiment was carried out in a greenhouse, with a sandy-clay soil with 2.18 dag kg-1 of organic matter, in pots of 3 dm³ capacity. The experiment was arranged in a 10 x 4 x 4 factorial scheme in a randomized block design with three replications. The treatments consisted of: 10 species, four tebuthiuron doses (0.0; 0.5; 1.0 e 2.0 kg ha-1) applied in pre-emergence, and four evaluation times (15, 30, 45, and 60 days after sowing). Phytotoxicity, plant height and, above-ground, root and total biomass dry matter were evaluated. Canavalia ensiformes and Pennisetum typhoides were tolerant to tebuthiuron at the dose of 0.5 kg ha-1, and Estizolobium aterrimum up to the dose of 1.0 kg ha-1, with the latter showing less phytotoxicity symptoms and a smaller reduction of plant height, above-ground, root, and total biomass dry matter, as compared to the control treatment.

F.R., Pires; C.M., Souza; A.A., Silva; M.E.L.R., Queiroz; S.O., Procópio; J.B., Santos; E.A., Santos; P.R., Cecon.

232

Seleção de plantas com potencial para fitorremediação de tebuthiuron / Plant selection with potential for tebuthiuron phytodecontamination  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho teve como objetivo selecionar espécies tolerantes ao tebuthiuron, visando utilizá-las em programas de fitorremediação de solos contaminados com esse herbicida. Foram avaliadas: Amaranthus hybridus, Crotalaria juncea, Chamaesyce hyssopifolia, C. hirta, Canavalia ensiformes, Helianthus a [...] nnus, Pennisetum typhoides, Estizolobium aterrimum, Raphanus raphanistrum e Crotalaria incana. O experimento foi conduzido em casa de vegetação, em vasos contendo 3 dm³ de solo de textura argilo-arenosa com 2,18 dag kg¹ de matéria orgânica. O experimento foi delineado em blocos ao acaso, com três repetições de tratamentos em fatorial 10 x 4 x 4, os quais foram constituídos por 10 espécies, quatro doses de tebuthiuron (0,0; 5,0; 1,0; e 2,0 kg ha-1), aplicadas em pré-emergência, e quatro épocas de avaliação (15, 30, 45 e 60 dias após a semeadura). Foram avaliadas a fitotoxicidade do herbicida, a altura de plantas e a massa de matéria seca da parte aérea, de raízes e do total da planta. Canavalia ensiformes e Pennisetum typhoides foram tolerantes ao tebuthiuron na dose de 0,5 kg ha-1. Estizolobium aterrimum tolerou tebuthiuron até a dose de 1,0 kg ha¹, apresentando fitotoxicidade menos acentuada e menor redução de altura de plantas e da massa de matéria seca da parte aérea, de raízes e do total da planta em relação ao tratamento testemunha. Abstract in english This study aimed to select tebuthiuron- tolerant plants to use them in phytoremediation programs in contaminated soils. The evaluated species were: Amaranthus hybridus, Crotalaria juncea, C. hyssopifolia, Chamaesyce hirta, Canavalia ensiformes, Helianthus annus, Pennisetum typhoides, Estizolobium at [...] errimum, Raphanus raphanistrum and Crotalaria incana. The experiment was carried out in a greenhouse, with a sandy-clay soil with 2.18 dag kg-1 of organic matter, in pots of 3 dm³ capacity. The experiment was arranged in a 10 x 4 x 4 factorial scheme in a randomized block design with three replications. The treatments consisted of: 10 species, four tebuthiuron doses (0.0; 0.5; 1.0 e 2.0 kg ha-1) applied in pre-emergence, and four evaluation times (15, 30, 45, and 60 days after sowing). Phytotoxicity, plant height and, above-ground, root and total biomass dry matter were evaluated. Canavalia ensiformes and Pennisetum typhoides were tolerant to tebuthiuron at the dose of 0.5 kg ha-1, and Estizolobium aterrimum up to the dose of 1.0 kg ha-1, with the latter showing less phytotoxicity symptoms and a smaller reduction of plant height, above-ground, root, and total biomass dry matter, as compared to the control treatment.

F.R., Pires; C.M., Souza; A.A., Silva; M.E.L.R., Queiroz; S.O., Procópio; J.B., Santos; E.A., Santos; P.R., Cecon.

2003-12-01

233

The Potential Use of an Alternative Fluid for SFR Intermediate Loops: Selection and First Design  

International Nuclear Information System (INIS)

Among the Generation IV systems, Sodium Fast Reactors (SFR) are promising and benefit of considerable technological experience, but improvements are researched on safety approach and capital cost reduction. One of the main problems to be solved by the standard SFR design is the proper management of the risk of leakage between the intermediate circuit filled with sodium and the energy conversion system using a water Rankine cycle. This risk requires notably an early detection of water leakage to prevent a water-sodium reaction, and adequate draining and pressure resistant components to mitigate the reaction consequences. One can think also to suppress this risk by replacing the sodium in the secondary loops by an alternative fluid, less reactive with water. This alternative fluid might also allow innovative designs, e.g. Intermediate Heat eXchanger (IHX) and Steam Generator Unit (SGU) grouped in the same component. CEA, AREVA and EDF have formed a working group in order to evaluate different 'alternative fluids' that might replace sodium. A first selection retained seven fluids on the bases of 'required properties' as: large operating range (low melting point, high boiling point ...), fluid cost and availability, acceptable corrosion at SFR working temperature. These are three bismuth alloys, two nitrate salts, one molten hydroxide and sodium with nanoparticles. Then, it was decided to evaluate these fluids through a multi-criteria analysis in order to point out advanteria analysis in order to point out advantages and drawbacks of each fluid and to compare them with sodium. Lack of knowledge, impact on materials, design, working conditions and reactor availability should be emphasized by this analysis, in order to provide sound arguments for a research program on one or two most promising fluids. A global note is given to each fluid by evaluating them with respect to 'major criteria', weighted differently according to their importance. The major criteria were: thermal properties, reactivity with structures, reactivity with other fluids (air, water, sodium), chemistry control (including tritium management), safety and waste management, In Service Inspection and Repair (ISI and R), impact on components and circuits, availability and cost, level of use. The impact on reactor availability and manageability and the level of knowledge on each fluid were estimated through the former criteria and introduced in the final evaluation as main criteria. The aim of this paper is to present the method of evaluation, the results obtained and the choice that have been made. The impact on design and operation are enhanced for the most promising fluids. It was found that sodium remains the most interesting intermediate fluid regarding all the criteria, and despite its reaction with water. Lead Bismuth Eutectic presents some interests and should be further evaluated. It is however clear that this fluid raises a number of issues, such as corrosion of steel, which would request to lower operating temperature, or to find new materials and then lengthy R and D. (author)

234

137Cs in recent tsunami deposits - a potential tracer of selective tsunami sediment entrainment?  

Science.gov (United States)

The tsunami of 27 February, 2010 affected a 600 km long stretch of the central Chilean coastline. We documented the tsunami deposits 4 months after the event in 2010 and two years later in 2012. The broad coastal plain at La Trinchera was inundated ca. 430 m inland and up to 8 m above sea level. A ca. 10 cm thick layer of tsunami sand was deposited on top of marsh sediments. A comparison of this layer in 2010 and 2012 reveals a change in the relative mineral composition and related grain size. In 2010 the layer consisted of 90-93% heavy minerals, 1-4% quartz, 2-3% organics and 1-3% feldspar. In 2012 the relative abundances changed to 63-76% heavy minerals, 10-12% quartz, 16-20% organics and 5-7% feldspar, as a result of the erosion of parts of the finer grained heavy minerals. Furthermore, the thickness decreased to ca. 8 cm. The concentration of the artificial radionuclide 137Cs was recorded using high-resolution gamma-spectrometry. Especially in the northern hemisphere, 137Cs is a tracer for radioactive fallout emitted mainly during nuclear tests in the 1950s to 1960s, peaking around 1963, or nuclear bombing and accidents. In contrast, Cs-concentrations in the southern hemisphere are about four times lower (marine deposits due to Cs-dilution in sea water. For recent (younger than ca. 60 years) onshore tsunami sediments, a mixed Cs-signal is expected because a tsunami can entrain sediments from different depositional environments and different stratigraphic age levels. At La Trinchera, gamma-spectrometry revealed a 137Cs-content of 0.5 Bq/kg for the lower ca. 5 cm of the tsunami layer. The 137Cs-concentration of the upper 5 cm was below the detection limit of 0.1 Bq/kg. Even though the tsunami layer appears to be structureless, the Cs-content may help to distinguish between two distinctive depositional units within the layer. We suggest that the lower part represents reworked onshore deposits with higher Cs-concentrations compared to the upper part that may be composed of material from mainly marine sources. The sediments constituting the upper part of the tsunami deposit may have been stored in shallow marine environments for more than ca. 60 years. Hence, they do not exhibit 137Cs and were not affected by later Cs-fallout because the nuclides were diluted in the sea water. Two transport scenarios for the 2010 Chile tsunami at La Trinchera seem to be possible: 1) The head of an individual onshore flowing wave of the tsunami wave train picked up both beach sand and onshore sediments, whereas the tail entrained shallow marine sediments. As the front of the wave decelerated during its inland flow, these sediments with high Cs-contents were deposited first. Subsequently, marine sediments without a detectable Cs-content reached the shore with some time delay and were then deposited on top. 2) Assuming that a tsunami consists of several waves with different magnitudes, it is possible that an earlier, less energetic wave, entrained sediments onshore, mixed and deposited them. A later, more energetic wave was then able to entrain marine sediments and deposit them on top. Whichever scenario might be more realistic, the Cs-signal may help to document selective, time-dependent erosion and deposition during tsunami inundation.

Spiske, M.; Bahlburg, H.; Suckow, A.

2012-12-01

235

Toxicity, sublethal effects, and potential modes of action of select fungicides on freshwater fish and invertebrates  

Science.gov (United States)

Despite decades of agricultural and urban use of fungicides and widespread detection of these pesticides in surface waters, relatively few data are available on the effects of fungicides on fish and invertebrates in the aquatic environment. Nine fungicides are reviewed in this report: azoxystrobin, boscalid, chlorothalonil, fludioxonil, myclobutanil, fenarimol, pyraclostrobin, pyrimethanil, and zoxamide. These fungicides were identified as emerging chemicals of concern because of their high or increasing global use rates, detection frequency in surface waters, or likely persistence in the environment. A review of the literature revealed significant sublethal effects of fungicides on fish, aquatic invertebrates, and ecosystems, including zooplankton and fish reproduction, fish immune function, zooplankton community composition, metabolic enzymes, and ecosystem processes, such as leaf decomposition in streams, among other biological effects. Some of these effects can occur at fungicide concentrations well below single-species acute lethality values (48- or 96-hour concentration that effects a response in 50 percent of the organisms, that is, effective concentration killing 50 percent of the organisms in 48 or 96 hours) and chronic sublethal values (for example, 21-day no observed adverse effects concentration), indicating that single-species toxicity values may dramatically underestimate the toxic potency of some fungicides. Fungicide modes of toxic action in fungi can sometimes reflect the biochemical and (or) physiological effects of fungicides observed in vertebrates and invertebrates; however, far more studies are needed to explore the potential to predict effects in nontarget organisms based on specific fungicide modes of toxic action. Fungicides can also have additive and (or) synergistic effects when used with other fungicides and insecticides, highlighting the need to study pesticide mixtures that occur in surface waters. For fungicides that partition to organic matter in sediment and soils, it is particularly important to determine their effects on freshwater mussels and other freshwater benthic invertebrates in contact with sediments, as available toxicity studies with pelagic species, mainly Daphnia magna, may not be representative of these benthic organisms. Finally, there is a critical need for studies of the chronic effects of fungicides on reproduction, immunocompetence, and ecosystem function; sublethal endpoints with population and community-level relevance.

Elskus, Adria A.

2012-01-01

236

Climate Past and Present: A Study on Glaciology of Himalayas in India  

Science.gov (United States)

Glaciers are moving bodies of ice and snow, which are normally present above the snow line. Glaciers and ice sheets are hundreds to more than one thousand meters thick and change significantly only over decades. On these longer time scales they can influence atmospheric circulation and global sea levels. Glaciers play an important role in maintaining ecosystem stability as they act as buffers and regulate the runoff water supply from high mountains to the plains during both dry and wet spells. The present study is an attempt to analyze the Climate of the Past and Present of the Himalayas with reference to study the glaciology. The study also attempted to use the remote sensed data to explore the past and present situation of glaciology of the Himalayas. Since mountain glaciology of Himalayas played a vital role and stand as an example to explore the possibility of the climate change that occurred from the past to the present and also to determine the status in the future. The Study was based on the secondary and primary data collected from available sources and also collected from various published records to document the evidences for the same. It was observed that the Himalayan glaciers account for about 70% of the world’s non-polar glaciers and affect the lives of millions of people in several countries: China, India, Pakistan, Afghanistan, Nepal and Bangladesh. Their runoff feeds two of the oldest rivers in the world, the Indus and the Ganges, whose tributaries carry precious water for 500 million people on the northern Indian plains. Most of the glaciers in the Himalayas are of a summer-accumulation type, that is major accumulation and ablation take place simultaneously during summer (Fujita et. al, 1997). The glaciers of the Himalayas include some of the longest outside the Polar Regions and reached their largest extent during the end of the last ice age (more than 20,000 years ago). The evidence of these large ice masses can be seen in 'U' shaped valleys, which characterize much of the higher Himalayas. On the basis of their mode of occurrence and dimensions, glaciers have broadly been classified into three categories: valley glaciers, piedmont glaciers and continental glaciers. Himalayan glaciers fall in the category of valley glaciers. It has been estimated that an area of about 32,000 sq. km is under permanent cover of ice and snow in the Himalayas (Negi, 1991). This amounts to about 17% of the total geographical area of the Himalayas. Higher concentration of glaciers in the Himalayas lie in the regions with the highest mountain peaks, that is, Nanga Parbat, Nun Kun, Kinner Kailash, Nanda Devi, Nanda Kot, Annapurna, Mt. Everest, Makalu and Kanchanjunga. There are a number of small, medium and large size glaciers in the Himalayan ranges with typical landform features. Some of the famous and important ones include Baltoro glacier, Gangotari glacier, Gasherbrum glacier, Siachen glacier, Kanchanjunga glacier and Hispar glacier. Of these, the Siachen glacier is the most well known, on account of its strategic significance in the South Asian region. Glaciers are dynamic in nature; they grow and shrink in response to changing climate. During the Pleistocene era (2 million years ago) glaciers occupied about 30% of the total area of the earth as against 10% at present.

Shanmuganandan, S.

2003-04-01

237

Glacier length, area and volume changes in the Himalaya: an overview and specific examples  

Science.gov (United States)

The Himalaya comprises one of the largest glacier-covered areas outside the polar regions. Glaciers are of special interest for several reasons. For instance, receding glaciers can cause the development of hazardous glacial lakes and glaciers contribute to the overall river runoff. The importance of the glacier melt to run off, however, varies significantly depending especially on the precipitation regime. Previous studies indicate that the vast majority of the Himalayan glaciers retreated during the recent decades with only few exemptions. Although the numbers of investigates glaciers increased in the last few years, there is still a lack of knowledge about the glacier behaviour in the different regions of the Himalaya. Existing length measurements in the Indian Himalaya show continuous retreat with an accelerating trend in recent years for most of the glaciers. The annual retreat rates vary between ~5m and more than 50m. However, several measurements are based on topographic maps or coarse satellite data and can have therefore higher uncertainties. Own reassessments for the debris-covered Gangotri Glacier situated in Garhwal Himalaya/western India based on high resolution imagery such as Corona, Hexagon, IRS PAN, LISS IV, and Cartosat-1 show an continuous retreat with an average rate of 19.9 ± 0.3 m a-1 from 1965 to 2006. This is significant but less than previously published. Similar results were revealed for the area changes in upper Alaknanda and Bhagirathi valleys in Garhwal Himalaya. We found a lower but still significant area loss of 4.6 ± 2.8 % between 1968 and 2006. Area changes in Khumbu Himalaya/Nepal are with ~5% between 1962 and 2005 comparable. Investigations in the Greater Himalayan Range in southern Ladakh/northwest India revealed a general receding trend but with some of the larger glaciers with high altitude catchments being stable or even advancing. Preliminary results for Shyok Valley (Jammu and Kashmir) show on average stable or slightly advancing glaciers. This is consistent with existing studies of the Karakoram glaciers. However, area and length changes show indirect signals only while the mass balance is most directly linked to climate. Debris cover on glaciers which is common throughout the Himalaya further influences glacier melt. Existing studies show that area and length changes are reduced in comparison to debris-free glaciers. Currently no long-term in-situ glacier mass balance measurements exist. Remote sensed derived geodetic mass balance estimations are a suitable tool to improve the knowledge on the reaction of glaciers to climate change. Detailed investigations on the debris-covered glaciers in Khumbu Himalaya based on stereo Corona, ASTER and Cartosat-1 data revealed a specific mass balance of -0.32 ± 0.08 m w.e. a-1 between 1972 and 2007 which is within the global mean. The surface lowering is significant for all glaciers despite thick debris-cover. Consistently, preliminary results of the large debris-covered Zemu Glacier in Sikkim/Eastern Indian Himalaya indicate significant mass loss but only a slight reduction in length. Further analyses are under way and also climatic considerations will be addressed.

Bolch, T.; Bhambri, R.; Kamp, U.; Pieczonka, T.

2011-12-01

238

Desensitization of transient receptor potential ankyrin 1 (TRPA1) by the TRP vanilloid 1-selective cannabinoid arachidonoyl-2 chloroethanolamine.  

Science.gov (United States)

Recent studies on cannabinoid-induced analgesia implicate certain transient receptor potential (TRP) channels as a therapeutic target along with metabotropic cannabinoid receptors. Although TRP ankyrin 1 (TRPA1)-selective cannabinoids, such as (R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl) pyrrolo-[1,2,3-d,e]-1,4-benzoxazin-6-yl]-1-naphthalenyl-methanone (WIN55,212), are effective at desensitizing TRPA1 and TRP vanilloid 1 (TRPV1), there is a gap in knowledge in understanding the opposite situation, namely whether TRPV1-selective cannabinoids desensitize TRPA1. We selected the TRPV1-specific synthetic cannabinoid, arachidonoyl-2 chloroethanolamine (ACEA), to study peripheral antihyperalgesic properties because ACEA is known to activate TRPV1. Hence, we used in vitro as well as in vivo assays to evaluate the following: 1) the effects of ACEA on the TRPA1-selective agonist, mustard oil (MO), for calcitonin gene-related peptide (CGRP) release from rat hindpaw skin in vitro; 2) the effects of a peripherally selective dose of ACEA on MO-induced nocifensive behavior in vivo; and 3) the effects of five ACEA-insensitive TRPV1 mutations on ACEA-inhibition of MO-evoked calcium accumulation using a Chinese hamster ovary cell expression system. Our results demonstrate that 1) ACEA significantly attenuated (?40%) MO-evoked CGRP release from rat hindpaw skin, and this effect was not antagonized by the TRPV1 antagonist, capsazepine; 2) ACEA significantly inhibited (?40%) MO-induced nocifensive behavior in wild-type mice but not in TRPV1 knockout mice; and 3) all TRPV1 mutations insensitive to ACEA lacked the ability to inhibit MO-evoked calcium accumulation in Chinese hamster ovary cells transfected with TRPV1 and TRPA1. Taken together, the results indicate that a TRPV1-selective cannabinoid, ACEA, inhibits MO-evoked responses via a TRPV1-dependent mechanism. This study strengthens the hypothesis that cannabinoids mediate their peripheral analgesic properties, at least in part, via the TRP channels. PMID:21441412

Ruparel, Nikita B; Patwardhan, Amol M; Akopian, Armen N; Hargreaves, Kenneth M

2011-07-01

239

Assessment of the antioxidant potential of selected plant extracts--in vitro and in vivo experiments on pork.  

Science.gov (United States)

The antioxidant potential of selected plant extracts was assessed in vitro and in vivo experiments on pork. In the in vitro experiment, the anti-oxidative capacity of ethanol-water extract of Melissa officinalis (MW), ethanol-propylene-glycol extracts of M. officinalis (MP), Origanum vulgaris (O) and Salvia officinalis (S) at different dilutions was analysed. Furthermore a 2% essential oil concentrate was added to Origanum (OSi) and Salvia (SSi). In the two in vivo experiments in total 104 Slovak White Meaty pigs were fed with plant extracts (MW and O) at different doses with/without additional vitamin E. In the in vitro experiment Melissa (MW) showed a higher antioxidant potential compared to Origanum and Salvia assessed by TEAC assay. Addition of essential oil to Origanum improved substantially the anti-oxidative capacity. In the in vivo experiment the highest muscle anti-oxidative effect was obtained by feeding 60 ml Origanum. Small improvement in muscle antioxidant potential was observed by feeding Melissa or Origanum in combination with vitamin E. By feeding 10 ml Melissa, Origanum or Salvia the meat quality parameters such as pH(1) and pH(24), drip loss and shear force was not affected. After 5 days storage of meat the redness value was positively affected. PMID:20488625

Lahucky, Rudolf; Nuernberg, Karin; Kovac, Lubomir; Bucko, Ondrej; Nuernberg, Gerd

2010-08-01

240

Sensitive and selective determination of molybdenum by flow injection chemiluminescence method combined with controlled potential electrolysis technique  

Energy Technology Data Exchange (ETDEWEB)

A sensitive and selective flow injection chemiluminescence (CL) method combined with controlled potential electrolysis technique was described for the determination of molybdenum. The method is based on the chemiluminescence reaction of luminol with unstable molybdenum(III) in alkaline solution. The molybdenum(III) was on-line reduced from molybdenum(VI) via controlled potential electrolysis technique using a homemade flow-through carbon electrolytic cell at the potential of -0.6 V (versus Ag/AgCl). The method allows the determination of molybdenum in the 5.0x10{sup -10} to 5.0x10{sup -7} g ml{sup -1} range with a limit of detection (3{sigma}) of 5x10{sup -11} g ml{sup -1} molybdenum. The relative standard deviation is 2.6% for the 1.0x10{sup -9} g ml{sup -1} molybdenum solution in 11 repeated measurements. This method was successfully applied to the determination of molybdenum in water samples.

Du Jianxiu; Li Jianjun; Yang Lingjuan; Lu Jiuru

2003-04-03

 
 
 
 
241

Facile photochemical synthesis of mixed siloxyacetal glycosides as potential pH-sensitized prodrugs for selective treatment of solid tumors.  

Science.gov (United States)

Photochemical reactions of a variety of acylsilanes with peracetylated free glycosides in anhydrous benzene at ambient temperature yielded novel, highly acid-sensitive siloxyacetal glycosides in 75-90% yields with complete retention of configuration at the anomeric center. Subsequent deacetylation of triisopropylsiloxy- and tert-butyldimethylsiloxy derivatives with sodium methoxide in methanol afforded deprotected siloxyacetal glycosides in nearly quantitative yields. Acid hydrolysis of trimethylsilyl siloxyacetals proceeded with a half-life of 17.5 minutes at pH 6.2 which is vastly superior to the decomposition rate of conventional acetals under similar conditions. The structure of one of the novel siloxyacetals was confirmed by X-ray crystallography. In vitro biological studies showed that glucose-derived siloxyacetals may serve as potential pH-activated prodrugs for selective treatment of solid tumors. PMID:15505722

Svarovsky, Serge A; Taraban, Marc B; Barchi Jr, Joseph J

2004-11-01

242

Selection of Potential Antagonistic Bacillus and Trichoderma Isolates from Tomato Rhizospheric Soil Against Fusarium oxysporum f.sp. lycoperscisi  

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Full Text Available The aim of the investigation was to obtain a potential indigenous biocontrol agent against Fusarium oxysporum f.sp. lycopersici on tomato from different agroclimatic zones in India. Wide collection of Trichoderma and Bacillus was conducted from tomato rhizospheric soil in IIVR farm (Varanasi, IIHR farm (Bangalore, IARI farm (Rajendra Nagar and farm of APHU (T.P. Gudem by using Trichoderma Specific Media (TSM and Nutrient Agar (NA. As a result, total 65 strains were cultured and maintained in which 28 were Bacillus and 37 were Trichoderma, respectively. On the basis of in vitro bioassays viz., dual culture and poisoned food technique it was concluded that 3 most prominent Trichoderma isolates viz., DPNST-4, -8 and -29 and four most prominent of DPNSB-2, -11, -18 and -28 from Bacillus were selected.

N. Thajuddin

2011-01-01

243

Large radiative forcing efficiency of atmospheric aerosols over the Himalaya  

Science.gov (United States)

This study is based on measurements made at the Nepal Climate Observatory at Pyramid (NCO-P, 27.95 N, 86.82 E), located at 5079 m altitude in the Sagamartha National Park, Eastern Nepal Himalaya. We analised seasonal variations of solar downward irradiance (SW), columnar water vapour content (wv), aerosol optical depth at 500 nm (?) and surface albedo (A) in the period between 2007 and 2010, in order to obtain the radiative perturbations produced by aerosols in the SW. SW measurements are carried out by a CMP21 pyranometer, while A is derived from a CNR1 radiometer. Values of wv and ? are retrieved from the measurements by the EVK2-CNR Cimel sunphotometer operating within the AERONET network. ? was found to be lower than 0.1 in 98% of the cases. However, during the pre-monsoon season, especially in the months of April and May, cases with ? reaching 0.27 were recorded. The aerosol surface shortwave radiative effect in cloud-free periods was estimated during the elevated aerosol optical depth cases using different methods. The 'hybrid method' was applied using experimental measurements of solar downward irradiance and simulations made with the MODTRAN (MODerate resolution atmospheric TRANsmission) model. The dependency of SW on A and wv was determined from MODTRAN simulations, and was used to correct experimental measurements for albedo and water vapour changes. The radiative perturbation produced by aerosol was thus obtained as the difference between the measured irradiances and the modelled values for aerosol-free conditions and the same water vapour and albedo values, and at the same solar zenith angle. The aerosol radiative effect was also derived by comparing elevated and low aerosol optical depth cases, at similar values of solar zenith angle, albedo, and column water vapour. In addition the direct method, relating SW to changes in ?, was also used. These three methods produce consistent results. Although the overall aerosol radiative perturbation is small, it becomes relatively large during elevated aerosol cases. The radiative forcing efficiency (radiative effect produced by a unit aerosol optical depth) is significantly larger than at other sites worldwide, reaching values above 360 W/m2 at about 50° solar zenith angle. The maximum radiative effect is about -90±18 Wm-2 (for ?=0.25), corresponding to a reduction by more than 10% of the solar radiation at the surface. During these elevated aerosol events high concentrations of pollutants were measured: PM10 and PM 2.5 showed concentrations higher than 50 ng m-3, while the black carbon concentration reached 3000 ng m-3. The backtrajectory analysis for the elevated aerosol cases shows that the polluted airmasses observed at NCO-P come from Indo-Gangetic plain and Punjab, regions characterized by the highest industrial and demographic concentration of the Indian subcontinent.

Gasbarra, Daniele; di Sarra, Alcide; Meloni, Daniela; Bonasoni, Paolo; Di Biagio, Claudia; Gobbi, Gian Paolo; Marinoni, Angela; Pietro Verza, Gian; Vuillermoz, Elisa

2014-05-01

244

Substrate selectivity, potential sensitivity and stoichiometry of Na(+)-nucleoside transport in brush border membrane vesicles from human kidney.  

Science.gov (United States)

Recently, we demonstrated the presence of a Na(+)-nucleoside cotransport mechanism that transports both purine and pyrimidine nucleosides in human renal brush-border membrane vesicles (BBMV) (Gutierrez et al. (1992) Biochim. Biophys. Acta 1105, 1-9). The objective of this study was to further elucidate the characteristics of this cotransport system in terms of electrical potential sensitivity, stoichiometry and substrate selectivity with respect to nucleoside analogs. In BBMV from human kidney, Na(+)-thymidine uptake was stimulated by an inside negative potential difference created by K+ and valinomycin. A hyperbolic relationship between initial rate of uridine uptake and Na+ concentration was obtained suggesting a Na(+)-nucleoside coupling stoichiometry of 1:1. Our previous study had demonstrated that the pyrimidines, thymidine, cytidine, and uridine and the purines, adenosine, 2'-deoxyadenosine, and guanosine, but not inosine and formycin B, were substrates of this system. To further define the substrate selectivity of the transporter, the interaction of the drugs, 2-chloroadenosine (2-ClAdo), 5-fluorouridine (5-FUrd) and 5-iodo-2'-deoxyuridine (5-IdUrd), nucleoside analogs that are modified on the base moiety was studied. The three compounds inhibited Na(+)-thymidine uptake in the vesicles via a competitive mechanism. The IC50 values for 2-ClAdo, 5-FUrd and 5-IdUrd were 75, 49, and 16 microM, respectively. In addition, 5-IdUrd trans-stimulated the initial uptake of thymidine into the vesicles suggesting that the two compounds share the same transporter. Collectively, these data suggest that Na(+)-nucleoside transport in the human renal brush-border membrane is an electrogenic process and that the kidney may play a role in the disposition and targeting of clinically important nucleoside analogs. PMID:8323939

Gutierrez, M M; Giacomini, K M

1993-07-01

245

Violation of the electric dipole selection rules in indirect multiphoton excitation of image potential states on Ag(100)  

International Nuclear Information System (INIS)

Full text: Photoemission from image potential states (IPS) on Ag(100) is investigated using angle resolved multiphoton photoemission induced by 150 fs laser pulses. For the first time we demonstrate that IPS populated by indirect transitions can be observed with light polarized parallel to the plane of incidence and light polarized normal to the plane of incidence. The latter is a process normally forbidden by the dipole transition selection rules. These findings are related to the creation of a hot electron population. This interpretation is supported by the reduction of the IPS electron effective mass, about 6%, when measured by indirect multiphoton population, followed by one- photon photoemission. The change of the effective mass is attributed to the interaction, with momentum exchange, between the non-equilibrium electron population in the bulk and the IPS. As a result of the momentum exchange the electronic excitations are not restricted anymore by the polarization selection rules. In the figure, panel A, photoemission spectra at hv = 4.28 eV in s and p polarization are shown. The inset represents a schematic energy level diagram at k parallel 0 of Ag(100) surface states, showing a direct one-photon population, two-photon photoemission via the n=1 IPS. In panel B, the spectra at hv 3.14 eV in s and p polarization are shown. In this case a direct population would be forbidden by dipole selection rules in s polarization, hence a indirect mechanism must be invokedence a indirect mechanism must be invoked

246

Potential social, institutional, and environmental impacts of selected energy-conservation measures in two Washington communities. [Seattle and Yakima  

Energy Technology Data Exchange (ETDEWEB)

The likely environmental, social, and institutional impacts of selected energy-conservation measures in two communities in Washington state are reported. The five conservation measures investigated in this study were: (1) retrofitting existing buildings; (2) district heating and Integrated Community Energy Systems (ICES); (3) small automobiles and vehicle redesign; (4) land-use and housing modifications; and (5) electric-utility rate reform. Twenty potential impact areas were selected for analysis. These areas were divided into five categories of environmental impacts, economic impacts, community impacts, personal impacts, and overall quality of life in the community. The research was conducted in Seattle and Yakima, Washington. In each location, about two dozen public officials and business, labor, and community leaders were interviewed. Their diverse views are summarized. The Seattle respondents saw energy conservation as a highly desirable policy with a number of temporary, transitional problems arising as energy-conservation measures were implemented. Yakima respondents, in contrast, did not expect to encounter many serious energy problems in the foreseeable future and consequently viewed energy conservation as a relatively minor community concern. Moreover, they anticipated that many conservation measures, if implemented by the government, would encounter either apathy or resistance in their community. Two broad generalizations can bedrawn from these interviews: (1) energy conservation will basically be beneficial for the natural environment and our society; and (2) if energy conservation does become a dominant thrust in our society, it could stimulate and reinforce a much broader process of fundamental social change. (LCL)

Edelson, E.; Olsen, M.

1980-03-01

247

The potential of selected macroalgal species for treatment of AMD at different pH ranges in temperate regions.  

Science.gov (United States)

The metal bioaccumulation potential of selected macroalgae species at different pH ranges was study for usage as part of a possible secondary passive acid mine drainage (AMD) treatment technology in algae ponds. Two separate studies were conducted to determine the suitability of macroalgae for passive treatment when metabolic processes in macrophytes and microorganisms in constructed wetlands decrease during winter months. In the field study, the bioconcentration of metals (mg/kg dry weight) measured in the benthic macroalgae mats was in the following order: site 1. Oedogonium crassum Al > Fe > Mn > Zn; site 2. Klebsormidium klebsii, Al > Fe > Mn > Zn; site 3. Microspora tumidula, Fe > Al > Mn > Zn and site 4. M. tumidula, Fe > Mn > Al > Zn. In the laboratory study, cultured macroalgae K. klebsii, O. crassum and M. tumidula isolated from the field sampling sites were exposed to three different pH values (3, 5 and 7), while bioaccumulation of the metals, Al, Fe, Mn and Zn and glutathione S-transferase (GST) activity were measured in the different selected algae species at a constant water temperature of 14 °C. Bioaccumulation of Al was the highest for O. crassum followed by K. klebsii and M. tumidula (p < 0.0001). From the study it was evident that the highest metal bioaccumulation occurred in the macroalgae O. crassum at all three tested pH values under constant low water temperature. PMID:24835955

Oberholster, Paul J; Cheng, Po-Hsun; Botha, Anna-Maria; Genthe, Bettina

2014-09-01

248

Knee-bend turn and compressed meandering on the Pam and Papum River due to tectonic forcing on the Sub-Himalaya of the Arunachal Himalaya, India  

Science.gov (United States)

The Pam and Papum River gets originated from the Lesser Himalayan region,passes through the Sub-Himalaya and confluences at an obtuse angle in a prong shape, guided by ENE-WSW, WNW-ESE trending lineaments and join the mighty Brahmaputra River as the Burai River after following more or less as a straigth channel,from the north.It follows NE-SW to NW-SE trending lineaments. These rivers show compressed meandering and take knee-bend turnings on its river flow from north to south. Papum Syncline with its axial trend of ENE-WSW passes through the river channels of these rivers. The Pam River channel shows upright beddings on its left bank, as the Tippi Thrust, in which the Lower Siwaliks thrust upon the Middle and Upper Siwaliks, passes through the river channel had truncated northern flank of the Papum syncline. Structural elements of folding and fault movements disturbed the Pam and Papum River channels, leading to compressed meandering. With the onset of Tippi thrust, the north to southward flowing Pam River changed its course by taking knee bend turning from NW-SE to E-W to ENE- WSW direction following the fault trend. Columns of upright sandstone and pebbly beds protruded have also been observed along the left bank of the Pam River. Structural control of the river channel is also indicated by another set of the protruding sandstone beds observed on the right bank of the Pam River with no extension on the left bank is observed on its confluence with Jote Stream. Papum River also takes N-S to NW-SE channel with an obtuse angle turning guided by Tippi thrust and meets the Pam River in a Y-shaped joining along a 8km long NE-SW trending fault plane. Active tectonic activities uplifted Quaternary deposits of gravels, sand and silt in the study area. Left lateral movement is also evident from the offsetting of the Pam river at its confluence with Jote stream by about 300m. Intense activity of folding and faulting related to the proximal tectonics of the Himalayan foreland basin (HFB) are witnessed in the study area. The occurrence of syncline, anticline and thrusting along with strike -slip movement exhibit the shortening of the HFB as the Indian plate converges northward beneath the Himalaya. The Pam and Papum River are forced to deflect their path and undergoes compressed meandering guided by the structural elements of folds and faults in the Arunachal Himalaya due to proximal tectonism of the HFB. Keywords: Sub-Himalaya; Compressed meandering; Papum Syncline; Tippi Thrust; Knee-bend turning; Himalayan Foreland Basin; Proximal Tectonics.

Devi, M.

2009-04-01

249

Health risk assessment and multivariate apportionment of trace metals in wild leafy vegetables from Lesser Himalayas, Pakistan.  

Science.gov (United States)

Fresh wild leafy vegetables and related soil samples were collected from Lesser Himalayas, Pakistan to evaluate the trace metal levels and related health risk to the consumers. The samples were prepared by acid digestion, followed by quantification of selected trace metals (Fe, Zn, Cu, Mn, Cr, Cd and Pb) on atomic absorption spectrophotometer. Generally, in the vegetables highest concentrations were detected for Fe, followed by Zn, Mn and Pb. Among the vegetables, highest concentrations of Zn, Cu and Cr were found in Solanum nigrum, while Stellaria media showed the elevated levels of Fe and Cd. Nevertheless, maximum concentrations of Mn and Pb were found in Convolvulus arvensis and Amaranthus viridis, respectively. In the case of soil, highest levels were observed for Fe, followed by Mn, Zn, Pb, Cr and Cu. Translocation of trace metals from soil to the vegetables exhibited highest values for Cd, followed by Zn. Multivariate principal component analysis showed significant anthropogenic contributions of the Pb, Cr, Zn, Cd and Fe in the vegetables. Health risk assessment was evaluated in terms of health risk index, target hazard quotient and hazard index which showed that the intake of some trace metals through vegetables was higher than the recommended values, consequently consumption of the vegetables may be associated with non-carcinogenic health risks. Nonetheless, elevated levels of Cr and Pb were also found to be associated with lifetime carcinogenic risk to the consumers. PMID:23490195

Abbasi, Arshad Mehmood; Iqbal, Javed; Khan, Mir Ajab; Shah, Munir H

2013-06-01

250

Response to genomic selection: The Bulmer effect and the potential of genomic selection when the number of phenotypic records is limiting  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Over the last ten years, genomic selection has developed enormously. Simulations and results on real data suggest that breeding values can be predicted with high accuracy using genetic markers alone. However, to reach high accuracies, large reference populations are needed. In many livestock populations or even species, such populations cannot be established when traits are difficult or expensive to record, or when the population size is small. The value of genomic selection is then questionable. Methods In this study, we compare traditional breeding schemes based on own performance or progeny information to genomic selection schemes, for which the number of phenotypic records is limiting. Deterministic simulations were performed using selection index theory. Our focus was on the equilibrium response obtained after a few generations of selection. Therefore, we first investigated the magnitude of the Bulmer effect with genomic selection. Results Results showed that the reduction in response due to the Bulmer effect is the same for genomic selection as for selection based on traditional BLUP estimated breeding values, and is independent of the accuracy of selection. The reduction in response with genomic selection is greater than with selection based directly on phenotypes without the use of pedigree information, such as mass selection. To maximize the accuracy of genomic estimated breeding values when the number of phenotypic records is limiting, the same individuals should be phenotyped and genotyped, rather than genotyping parents and phenotyping their progeny. When the generation interval cannot be reduced with genomic selection, large reference populations are required to obtain a similar response to that with selection based on BLUP estimated breeding values based on own performance or progeny information. However, when a genomic selection scheme has a moderate decrease in generation interval, relatively small reference population sizes are needed to obtain a similar response to that with selection on traditional BLUP estimated breeding values. Conclusions When the trait of interest cannot be recorded on the selection candidate, genomic selection schemes are very attractive even when the number of phenotypic records is limited, because traditional breeding requires progeny testing schemes with long generation intervals in those cases.

Van Grevenhof Elizabeth M

2012-08-01

251

Occurrences of damaging earthquakes between the Himachal and Darjeeling Himalayas: Tectonic implications  

Science.gov (United States)

Detailed analysis of intensity for ten damaging historical earthquakes in the central arcuate belt between the Himachal and Darjeeling Himalayas was carried out in the backdrop of isoseismal eccentricity, source depth and Indian plate obliquity. Results indicate that the elongated axes of the isoseismals and strike of ruptures for shallow earthquakes are almost parallel with strike of the Himalayan arc, and clearly conformable with the obliquity. An empirical power law relationship between eccentricity and focal depth established under the present study illustrates that the deeper events are more influenced by the bending of the penetrating Indian lithosphere, whereas the shallower events are principally controlled by the obliquity. A positive correlation between eccentricities and obliquity obviously supports this inference. The present study further reveals that the constant decrease in Indian plate obliquity from Himachal to Nepal-Bihar Himalaya is well compatible with the graben structures and horizontal shearing along this arcuate segment.

Ansari, Md. Afroz; Khan, Prosanta K.

2014-08-01

252

Genetic Issues of Some of the Non Metallic Minerals in Lesser Himalaya  

Directory of Open Access Journals (Sweden)

Full Text Available A brief account of the representative and workable industrial minerals namely magnesite, talc and barite in Lesser Himalaya, is presented here emphasizing their genesis. Deposits of magnesite and talc are found associated with Neoproterozoic, plateform type, shelf-slope limestone-dolomite host rocks from inner Lesser Himalayan sequences. Field, textural, geochemical signatures and fluid inclusions trapped in dolomite and magnesite reveal within basin processes, in an increased burial- diagenetic environment responsible for formation of magnesite replacing dolomite. Talc is formed at the expense of magnesite and silica, and with limited dolomite involvement at transition conditions from diagenetic to metamorphism. Barite deposit is hosted within Neoproterozoic Nagthat quartzite rocks of outer Lesser Himalaya, wherein its textures, fluid inclusion, sulfur and strontium isotopic studies helped in genetic understanding.

R. Sharma

2010-10-01

253

Optimization of Cat's Whiskers Tea (Orthosiphon stamineus) Using Supercritical Carbon Dioxide and Selective Chemotherapeutic Potential against Prostate Cancer Cells  

Science.gov (United States)

Cat's whiskers (Orthosiphon stamineus) leaves extracts were prepared using supercritical CO2 (SC-CO2) with full factorial design to determine the optimum extraction parameters. Nine extracts were obtained by varying pressure, temperature, and time. The extracts were analysed using FTIR, UV-Vis, and GC-MS. Cytotoxicity of the extracts was evaluated on human (colorectal, breast, and prostate) cancer and normal fibroblast cells. Moderate pressure (31.1?MPa) and temperature (60°C) were recorded as optimum extraction conditions with high yield (1.74%) of the extract (B2) at 60?min extraction time. The optimized extract (B2) displayed selective cytotoxicity against prostate cancer (PC3) cells (IC50 28?µg/mL) and significant antioxidant activity (IC50 42.8?µg/mL). Elevated levels of caspases 3/7 and 9 in B2-treated PC3 cells suggest the induction of apoptosis through nuclear and mitochondrial pathways. Hoechst and rhodamine assays confirmed the nuclear condensation and disruption of mitochondrial membrane potential in the cells. B2 also demonstrated inhibitory effects on motility and colonies of PC3 cells at its subcytotoxic concentrations. It is noteworthy that B2 displayed negligible toxicity against the normal cells. Chemometric analysis revealed high content of essential oils, hydrocarbon, fatty acids, esters, and aromatic sesquiterpenes in B2. This study highlights the therapeutic potentials of SC-CO2 extract of cat's whiskers in targeting prostate carcinoma. PMID:25276215

Al-Suede, Fouad Saleih R.; Khadeer Ahamed, Mohamed B.; Abdul Majid, Aman S.; Baharetha, Hussin M.; Hassan, Loiy E. A.; Kadir, Mohd Omar A.; Nassar, Zeyad D.; Abdul Majid, Amin M. S.

2014-01-01

254

Aldose reductase inhibitory, anti-cataract and antioxidant potential of selected medicinal plants from the Marathwada region, India.  

Science.gov (United States)

The water, ethanol and chloroform extracts of selected plants such as Adhatoda vasica (L.) (Acanthaceae), Caesalpinia bonduc (L.), Cassia fistula (L.) (Caesalpiniaceae) and Biophytum sensitivum (L.) (Oxalidaceae) were evaluated for rat lens aldose reductase inhibitory (RLAR) potential, anti-cataract and antioxidant activities. All the samples inhibited the aldose reductase considerably and exhibited anti-cataract activity, while C. fistula (IC(50), 0.154 mg mL(-1)) showed significant RLAR inhibitory activity as compared to the other tested samples, and was further found to be more effective in maintaining sugar-induced lens opacity in the rat lens model. The antioxidant potential of plant extracts was determined using DPPH (2,2-diphenyl-1-picryl hydrazine), hydroxyl (OH), nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) scavenging activities, along with determination of reducing power, ferrous ion chelating ability and inhibition of polyphenol oxidase (PPO). The extracts of the tested plant showed significant free radical scavenging activities and inhibited the activity of enzyme PPO, a model oxidising enzyme. The plant samples were found to possess considerable amounts of vitamin C, total polyphenols and flavonoids. PMID:21462076

Gacche, R N; Dhole, N A

2011-04-01

255

Optimization of Cat's Whiskers Tea (Orthosiphon stamineus) Using Supercritical Carbon Dioxide and Selective Chemotherapeutic Potential against Prostate Cancer Cells.  

Science.gov (United States)

Cat's whiskers (Orthosiphon stamineus) leaves extracts were prepared using supercritical CO2 (SC-CO2) with full factorial design to determine the optimum extraction parameters. Nine extracts were obtained by varying pressure, temperature, and time. The extracts were analysed using FTIR, UV-Vis, and GC-MS. Cytotoxicity of the extracts was evaluated on human (colorectal, breast, and prostate) cancer and normal fibroblast cells. Moderate pressure (31.1?MPa) and temperature (60°C) were recorded as optimum extraction conditions with high yield (1.74%) of the extract (B2) at 60?min extraction time. The optimized extract (B2) displayed selective cytotoxicity against prostate cancer (PC3) cells (IC50 28?µg/mL) and significant antioxidant activity (IC50 42.8?µg/mL). Elevated levels of caspases 3/7 and 9 in B2-treated PC3 cells suggest the induction of apoptosis through nuclear and mitochondrial pathways. Hoechst and rhodamine assays confirmed the nuclear condensation and disruption of mitochondrial membrane potential in the cells. B2 also demonstrated inhibitory effects on motility and colonies of PC3 cells at its subcytotoxic concentrations. It is noteworthy that B2 displayed negligible toxicity against the normal cells. Chemometric analysis revealed high content of essential oils, hydrocarbon, fatty acids, esters, and aromatic sesquiterpenes in B2. This study highlights the therapeutic potentials of SC-CO2 extract of cat's whiskers in targeting prostate carcinoma. PMID:25276215

Al-Suede, Fouad Saleih R; Khadeer Ahamed, Mohamed B; Abdul Majid, Aman S; Baharetha, Hussin M; Hassan, Loiy E A; Kadir, Mohd Omar A; Nassar, Zeyad D; Abdul Majid, Amin M S

2014-01-01

256

ECOLOGICAL STATUS AND IMPACT OF DISTURBANCE IN AN ALPINE PASTURE OF GARHWAL HIMALAYA, INDIA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The alpine area in Garhwal Himalaya is highly fragile and is known for its beautiful flora and fauna. The study area was located just below the Gangotri glacier which is the origin of Bhagirathi, a holy river of India. Pilgrimage, tourism, adventure activities and mules are the factors responsible for causing disturbance in this area. There is a remarkable variation in the values of diversity, species richness, dominance, density IVI and biomass production at Bhojbasa Protected (BP) and Bhojb...

MANOJ DHAULAKHANDI; Rajwar, Govind S.; MUNESH KUMAR

2010-01-01

257

Region-wide glacier mass balances over the Pamir-Karakoram-Himalaya during 1999-2011  

Science.gov (United States)

The recent evolution of Pamir-Karakoram-Himalaya (PKH) glaciers, widely acknowledged as valuable high-altitude as well as mid-latitude climatic indicators, remains poorly known. To estimate the region-wide glacier mass balance for 9 study sites spread from the Pamir to the Hengduan Shan (eastern Himalaya), we compared the 2000 Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) to recent (2008-2011) DEMs derived from SPOT5 stereo imagery. During the last decade, the region-wide glacier mass balances were contrasted with moderate mass losses in the eastern and central Himalaya (-0.22 ± 0.12 m w.e. yr-1 to -0.33 ± 0.14 m w.e. yr-1) and larger losses in the western Himalaya (-0.45 ± 0.13 m w.e. yr-1). Recently reported slight mass gain or balanced mass budget of glaciers in the central Karakoram is confirmed for a larger area (+0.10 ± 0.16 m w.e. yr-1) and also observed for glaciers in the western Pamir (+0.14 ± 0.13 m w.e. yr-1). Thus, the "Karakoram anomaly" should be renamed the "Pamir-Karakoram anomaly", at least for the last decade. The overall mass balance of PKH glaciers, -0.14 ± 0.08 m w.e. yr-1, is two to three times less negative than the global average for glaciers distinct from the Greenland and Antarctic ice sheets. Together with recent studies using ICESat and GRACE data, DEM differencing confirms a contrasted pattern of glacier mass change in the PKH during the first decade of the 21st century.

Gardelle, J.; Berthier, E.; Arnaud, Y.; Kääb, A.

2013-08-01

258

Region-wide glacier mass balances over the Pamir-Karakoram-Himalaya during 1999–2011  

Directory of Open Access Journals (Sweden)

Full Text Available The recent evolution of Pamir-Karakoram-Himalaya (PKH glaciers, widely acknowledged as valuable high-altitude as well as mid-latitude climatic indicators, remains poorly known. To estimate the region-wide glacier mass balance for 9 study sites spread from the Pamir to the Hengduan Shan (eastern Himalaya, we compared the 2000 Shuttle Radar Topography Mission (SRTM digital elevation model (DEM to recent (2008–2011 DEMs derived from SPOT5 stereo imagery. During the last decade, the region-wide glacier mass balances were contrasted with moderate mass losses in the eastern and central Himalaya (?0.22 ± 0.12 m w.e. yr?1 to ?0.33 ± 0.14 m w.e. yr?1 and larger losses in the western Himalaya (?0.45 ± 0.13 m w.e. yr?1. Recently reported slight mass gain or balanced mass budget of glaciers in the central Karakoram is confirmed for a larger area (+0.10 ± 0.16 m w.e. yr?1 and also observed for glaciers in the western Pamir (+0.14 ± 0.13 m w.e. yr?1. Thus, the "Karakoram anomaly" should be renamed the "Pamir-Karakoram anomaly", at least for the last decade. The overall mass balance of PKH glaciers, ?0.14 ± 0.08 m w.e. yr?1, is two to three times less negative than the global average for glaciers distinct from the Greenland and Antarctic ice sheets. Together with recent studies using ICESat and GRACE data, DEM differencing confirms a contrasted pattern of glacier mass change in the PKH during the first decade of the 21st century.

J. Gardelle

2013-08-01

259

GPS measurements of present-day convergence across the Nepal Himalaya  

Science.gov (United States)

The high elevations of the Himalaya and Tibet result from the continuing collision between India and Asia, which started more than 60 million years ago1-4. From geological and seismic studies of the slip rate of faults in Asia5, it is believed that approximately one-third of the present-day convergence rate between India and Asia (58 +/- 4mmyr-1) is responsible for the shortening, uplift and moderate seismicity of the Himalaya. Great earthquakes also occur infrequently in this region, releasing in minutes the elastic strain accumulated near the boundary zone over several centuries, and accounting for most of the advance of the Himalaya over the plains of India. The recurrence time for these great earthquakes is determined by the rate of slip of India beneath Tibet, which has hitherto been estimated indirectly from global plate motions6, from the slip rates of faults in Asia7,8, from seismic productivity9, and from the advance of sediments on the northern Ganges plain10. Here we report geodetic measurements, using the Global Positioning System (GPS), of the rate of contraction across the Himalaya, which we find to be 17.52 +/- 2 mm yr -1. From the form of the deformation field, we estimate the rate of slip of India beneath Tibet to be 20.5 +/- 2 mmyr-1. Strain sufficient to drive one or more great Himalayan earthquakes, with slip similar to that accompanying the magnitude 8.1 Bihar/Nepal 1934 earthquake, may currently be available in western Nepal.

Bilham, Roger; Larson, Kristine; Freymueller, Jeffrey

1997-03-01

260

Genetic Issues of Some of the Non Metallic Minerals in Lesser Himalaya  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A brief account of the representative and workable industrial minerals namely magnesite, talc and barite in Lesser Himalaya, is presented here emphasizing their genesis. Deposits of magnesite and talc are found associated with Neoproterozoic, plateform type, shelf-slope limestone-dolomite host rocks from inner Lesser Himalayan sequences. Field, textural, geochemical signatures and fluid inclusions trapped in dolomite and magnesite reveal within basin processes, in an increased burial- diagene...

Sharma, R.; Joshi, P.; Verma, P.

2010-01-01

 
 
 
 
261

Biodiversity Conservation through Traditional Beliefs System: A Case Study from Kumaon Himalayas, India  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The present study was carried out in Malay Nath sacred grove of Kumaon Himalaya, India, in appreciation of its role in biodiversity conservation. The whole grove is dedicated to the local deity “Malay Nath”, and showing semi-temperate type vegetation of the region. Rituals and cultural beliefs of the local peoples of Kumaon are plays significant role in conserving biodiversity. The study aimed at the documentation and inventory of the sacred grove, its phytodiversity, threats and conserv...

Singh, Harsh; Husain, Tariq; Agnihotri, Priyanka; Pande, Puran Chandra; Iqbal, Mudassar

2012-01-01

262

Glacial lake expansion in the central Himalayas by Landsat images, 1990-2010.  

Science.gov (United States)

Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed. PMID:24376778

Nie, Yong; Liu, Qiao; Liu, Shiyin

2013-01-01

263

An application of zeta potential method for the selection of nano-fluids to enhance IVR capability  

International Nuclear Information System (INIS)

In-vessel Retention (IVR) is one of the key severe accident management strategies that have been applied currently for advanced light water reactors such as APR1000 or APR1400. The concept of IVR consists of external cooling of the reactor vessel by flooding the reactor cavity to remove the decay heat from the molten core through the lower head of the vessel. However, the heat removal process is limited by the occurrence of critical heat flux (CHF) at the reactor vessel outer surface that may lead to a sharp increase of local temperature, damaging the integrity of the reactor vessel. In order to obtain higher power of nuclear reactors and to assure the achievement of the IVR capability during accident conditions, an enhancement of CHF at the outer surface of the vessel is required. The potential use of nano-fluids to increase the CHF is among the main IVR enhancing approaches. In this study, Al2O3 and CNT nano-fluids with different concentrations have been used as the potential coolant to enhance IVR capabilities. The dispersion stability of the nano-fluids was verified by zeta potential measurements. The results showed effects of time, concentration and pH on the stability of nanofluids. Three types of nano-fluids were selected as the candidates to apply for the IVR. A series of experiments have been performed in this study to understand the pool-boiling critical heat flux behavior on downward facing surfaces submerged in a pool of nano-fluids afaces submerged in a pool of nano-fluids at very low concentration. The inclination angle was changed from horizontal to vertical to investigate the effect of orientation on CHF enhancement which is needed for the application in IVR

264

An evaluation of the allelopathic potential of selected perennial groundcovers: foliar volatiles of catmint (Nepeta x faassenii) inhibit seedling growth.  

Science.gov (United States)

Six perennial groundcovers including Alchemilla mollis, Nepeta x faassenii, Phlox subulata, Sedum acre, Solidago cutleri, and Thymus praecox were investigated for the allelopathic potential of their respective foliar tissues via evaluation of volatile constituents produced by foliage. These groundcovers were selected for further laboratory evaluation because of superior performance as weed-suppressive groundcovers in previous field experiments. Foliar volatile components of N. x faassenii exhibited the strongest inhibitory effects on seedling growth of curly cress (Lepidium sativum), but S. cutleri also showed allelopathic potential by reducing shoot growth of curly cress seedlings with extracted volatiles. Although A. mollis and P. subulata exhibited strong weed-suppressive traits in past field experiments, weed suppression is apparently associated with either competition for resources or other allelopathic mechanisms rather than an allelopathic effect caused by volatiles. Volatiles of N. x faassenii were further evaluated with gas chromatography coupled to mass spectrometry (GC-MS). A total of 21 chemical constituents were identified in the volatile cocktail; 17 components were identified from a direct crude leaf sample extraction, including sabinene, beta-pinene, beta-myrcene, 2-(2-ethoxyethoxy)-ethanol, 1,8-cineole, ocimene, neryl Acetate, 4aalpha,7alpha,7aalpha-nepetalactone, alpha-copaene, trans-caryophyllene, alloaromadendrene, 4abeta,7alpha,7abeta-nepetalactone, germacrene D, beta-farnesene, chi-cadinene, germacrene B, and beta-sesquiphellandrene. Five additional constituents were identified in a methanolic extract of dried of N. x faassenii foliage, but not the volatile cocktail collected from N. x faassenii foliage. These included methyl benzoate, 2,4-decadienal, neryl acetate, isodihydronepetalactone, and caryophyllene oxide. Three components, 2-(2-ethoxyethoxy)-ethanol, alloaromadendrene, and chi-cadinene, were not only detected in both the volatile mixture and the methanolic extract, but also in an aqueous foliar extract that exhibited potential allelopathic activity. PMID:16900434

Eom, Seok Hyun; Yang, Hyun Seuk; Weston, Leslie A

2006-08-01

265

Tree ring inferred summer temperature variations over the last millennium in western Himalaya, India  

Energy Technology Data Exchange (ETDEWEB)

We report the first millennium-long reconstruction of mean summer (May-June-July-August) temperature extending back to AD 940 derived from tree-ring width data of Himalayan pencil juniper (Juniperus polycarpos C. Koch) from the monsoon-shadow zone in the western Himalaya, India. Centennial-scale variations in the reconstruction reveal periods of protracted warmth encompassing the 11-15th centuries. A decreasing trend in mean summer temperature occurred since the 15th century with the 18-19th centuries being the coldest interval of the last millennium, coinciding with the expansion of glaciers in the western Himalaya. Since the late 19th century summer temperatures increased again. However, current warming may be underestimated due to a weakening in tree growth-temperature relationship noticeable in the latter part of the 20th century. Mean summer temperature over the western Himalaya shows a positive correlation with summer monsoon intensity over north central India. Low-frequency variations in mean summer temperature anomalies over northwestern India are consistent with tree-ring inferred aridity in western North America. These far-distance linkages reported here for the first time underscore the utility of long-term temperature records from the western Himalayan region in understanding global-scale climatic patterns. (orig.)

Yadav, Ram Ratan [Birbal Sahni Institute of Palaeobotany, Lucknow (India); Braeuning, Achim [University of Erlangen-Nuremberg, Institute of Geography, Erlangen (Germany); Singh, Jayendra [University Greifswald, Ecosystem Dynamics, Institute of Botany and Landscape Ecology, Greifswald (Germany)

2011-04-15

266

Influence of regional precipitation patterns on stable isotopes in ice cores from the central Himalayas  

Science.gov (United States)

Several ice cores have been recovered from the Dasuopu (DSP) Glacier and the East Rongbuk (ER) Glacier in the central Himalayas since the 1990s. Although the distance between the DSP and the ER ice core drilling sites is only ~ 125 km, the stable isotopic record (?18O or ?D) of the DSP core is interpreted in previous studies as a temperature proxy, while the ER core is interpreted as a precipitation proxy. Thus, the climatological significance of the stable isotopic records of these Himalayan ice cores remains a subject of debate. Based on analysis of regional precipitation patterns over the region, we find that remarkable discrepancy in precipitation seasonality between the two sites may account for their disparate isotopic interpretations. At the ER core site, the Indian summer monsoon (ISM) precipitation is dominating due to topographic blocking of the moisture from westerlies by the high ridges of Mt. Qomolangma (Everest), which results in a negative correlation between the ER ?18O or ?D record and precipitation amount along the southern slope of the central Himalayas in response to the "amount effect". At the DSP core site, in comparison with the ISM precipitation, the wintertime precipitation associated with the westerlies is likely more important owing to its local favorable topographic conditions for interacting with the western disturbances. Therefore, the DSP stable isotopic record may be primarily controlled by the westerlies. Our results have important implications for interpreting the stable isotopic ice core records recovered from different climatological regimes of the Himalayas.

Pang, H.; Hou, S.; Kaspari, S.; Mayewski, P. A.

2014-02-01

267

Deformation and exhumation of the Bhutan Himalaya derived from the inversion of thermochronologic and thermometric data  

Science.gov (United States)

The kinematics of late Tertiary crustal deformation across the Himalaya has seen passionate debate over the past decade. Data acquisition and modelling studies have focused primarily on the western and central Himalaya, where findings about crustal deformation and exhumation, and the resulting thermal structure, have been extrapolated to elsewhere in the orogen. Although the major lithotectonic units and their bounding structures are remarkably continuous along strike, significant differences in other features limit the applicability of individual study conclusions to the greater orogen. In particular, the Eastern Himalaya of Bhutan are difficult to link to existing kinematic models, due to unique documented features including: (1) Preservation of Tethyan metasediments atop the Greater Himalayan Sequence (GHS) indicating a lower exhumation magnitude, (2) apatite fission-track (FT) ages markedly older than further west (3) a steep, convex topographic front spatially restricting modern orographic precipitation to foothill elevations of MHT), the India-southern Tibet convergence rate, its partitioning into over- and underthrusting of the Indian plate, radiogenic heat production and model basal temperature treated as free parameters. Preliminary model results suggest the MHT geometry varies from West to East and that the age distribution is particularly sensitive to the convergence rate partitioning; with respect to Nepal, we find slightly higher overthrusting values (~30% of the total convergence). Ongoing work will define the permissible range of other free parameters.

Coutand, I.; Grujic, D.; Whipp, D. M., Jr.; Bernet, M.; Fellin, M. G.; Landry, K.; McQuarrie, N.

2012-04-01

268

Influence of regional precipitation patterns on stable isotopes in ice cores from the central Himalayas  

Directory of Open Access Journals (Sweden)

Full Text Available Several ice cores have been recovered from the Dasuopu Glacier and the East Rongbuk (ER Glacier in the central Himalayas since the 1990s. Although the distance between the ER and the Dasuopu ice core drilling sites is only ?125 km, the stable isotopic record (?18O or ?D of the ER core is interpreted as a precipitation proxy while the Dasuopu core as a temperature proxy. Thus, the climatological significance of the stable isotopic records of these Himalayan ice cores remains a subject of debate. Based on analysis of regional precipitation patterns over the region, we find that the different interpretations of the Dasuopu and Everest isotopic records may not be contradictive. The north–south and west–east seesaws of the Indian Summer Monsoon (ISM precipitation are primarily responsible for precipitation falling at the ER site, which results in a negative correlation between the ER ?18O or ?D record and precipitation amount along the southern slope of the central Himalayas, corresponding to the "amount effect". In addition to the ISM precipitation, non-summer monsoonal precipitation associated with winter westerlies also significantly contributes to precipitation falling at the Dasuopu site, which may cause a positive correlation between the Dasuopu stable isotopic record and temperature, in response to the "temperature effect". Our results have important implications for interpreting the stable isotopic ice core records recovered from different climatological regimes of the Himalayas.

H. Pang

2013-05-01

269

NEPHELINE FORMATION POTENTIAL IN SLUDGE BATCH 4 AND ITS IMPACT ON DURABILITY: SELECTING GLASSES FOR A PHASE 3 STUDY  

Energy Technology Data Exchange (ETDEWEB)

Savannah River National Laboratory's frit development effort for SB4 is being driven by the most current CBU option for this sludge, referred to as Case 15C Blend 1. Candidate frits have been identified for this option via a paper study approach developed by Peeler and Edwards with the intent of down-selecting to a set of key frits whose operating windows (i.e., WL intervals that meet PCCS MAR criteria) are robust to and/or selectively optimal for this sludge option. The primary frits that appear attractive on paper (i.e., down-selected via the paper study) are now being incorporated into this experimental study. The potential for the formation of a nepheline primary crystalline phase is an important factor in frit development for SB4, due to the high Al{sub 2}O{sub 3} content of this sludge. Based upon earlier work by Li et al., glasses that do not satisfy the constraint: (SiO{sub 2}/SiO{sub 2} + Na{sub 2}O + Al{sub 2}O{sub 3}) > 0.62 where the oxides are expressed as mass fractions in the glass, will precipitate nepheline as their primary crystalline phase, hindering the durability of the glass. Based on the most recent compositional projection from the CBU for SB4 (Case 15C Blend 1), 16 glasses have been selected to complement the earlier work by continuing the investigation into the ability of the above constraint to predict the occurrence of a nepheline primary crystalline phase for SB4 glasses and into the impact of such phases on the durability of the SB4 glasses. Glasses were selected to cover WLs which tightly bound the nepheline discriminator value of 0.62, with the intent of refining this value to a level of confidence where it can be incorporated into offline administrative controls and/or the PCCS to support SME acceptability decisions. In addition, glass specimens at WLs of 35 and 40% will be prepared and analyzed to contribute needed data to the ComPro{trademark} database in anticipation of a variability study for SB4. The glasses in Table 4-3 are to batched and fabricated using standard procedures. Visual observations and other analytical techniques are to be used, as needed, to assess the presence of crystals with specific interest in the nepheline primary phase. The durability of these glasses (for both quenched and centerline canister cooled versions) is to be measured using the ASTM PCT Method A. The results from these efforts are to be documented in a subsequent report. The results of this study will provide valuable input for the frit development efforts and subsequent feedback to the CBU regarding the relative viability of the current SB4 option under consideration. The refined nepheline discriminator value will provide a guideline for the avoidance of nepheline crystallization in SB4 glasses and aid in down-selection of frit compositions. These data will be combined with the results of melt rate studies and a paper study of the frits robustness with regard to variability in the sludge composition to provide an optimized frit recommendation to DWPF for immobilization of SB4.

Fox, K

2006-01-27

270

Surface Velocities of Himalayan Glaciers: Implications for Glacial Erosion Potential During Climatic Change  

Science.gov (United States)

Mountain glaciers in the high elevations (> 3.5 km) of the Himalaya are very efficient erosion agents. Glacier size and thus the area affected by glacial erosion are controlled by climatic conditions. Understanding the impact of climate change and variability on glacial budgets and erosion requires knowledge of the erosive potential of glaciers, which is inferred to scale with ice flux. Here, we use ASTER satellite imagery in combination with the orthorectification and correlation tool COSI-Corr to derive horizontal surface velocities of glaciers from several regions across the Himalayan-Karakoram domain. Our results show that glaciers in the Eastern and Central Himalaya, where precipitation is mainly supplied by the Indian Summer Monsoon, are relatively slow, with velocities usually below 50-60 m/a. In contrast, glaciers in the Western Himalaya and Karakoram, receive a significant amount of precipitation during the winter months and are considerably faster with velocities often exceeding 80-100 m/a. This discrepancy is visible among glaciers of different size and orientation although local slope and catchment area effects may cause velocity excursions. A relatively sharp gradient appears to exist in the catchment area of the Sutlej River in the NW Himalaya of India at approximately 79°E. To the east, glaciers in the Garhwal Himalaya - among them Gangotri glacier, the largest in the Indian Himalaya - have mean velocities of around 20-40 m/a, whereas glaciers in the much drier Lahul region to the west attain mean velocities of around 30-60 m/a. Importantly, the Sutlej River valley marks a climatic transition zone from an annual summer-rainfall maximum (more than 75% of annual rainfall during the summer) to the east to a winter-rainfall maximum (more than 60% of annual rainfall during the winter) to the west. These observations corroborate the notion of a significant climatic boundary in this part of the Himalaya, which may have shifted west- and northward during past episodes of intensified summer monsoons, such as during the early Holocene. Our findings show that glaciers dominated by summer accumulation have generally lower surface velocities, hence ice-flux, and thus only limited potential to erode underlying bedrock. However, their counterparts in the Western Himalaya and Karakoram, receive moisture during all seasons, have a higher ice- flux, are more likely to have grown during an intensified winter or summer monsoon and thereby play a more important role in sculpting landscapes. Yet, if an intensified monsoon coincides with lower temperatures, such as during MIS 3-4, even glaciers in the Eastern and Central Himalaya should have had favourable conditions to advance toward much lower elevations, with higher ice flux.

Scherler, D.; Bookhagen, B.; Strecker, M. R.

2007-12-01

271

Geochemical characterization of supraglacial debris via in situ and optical remote sensing methods: a case study in Khumbu Himalaya, Nepal  

Directory of Open Access Journals (Sweden)

Full Text Available Surface glacier debris samples and field spectra were collected from the ablation zones of Nepal Himalaya Ngozumpa and Khumbu glaciers in November and December 2009. Geochemical and mineral compositions of supraglacial debris were determined by X-ray diffraction and X-ray fluorescence spectroscopy. This composition data was used as ground truth in evaluating field spectra and satellite supraglacial debris composition and mapping methods. Satellite remote sensing methods for characterizing glacial surface debris include visible to thermal infrared hyper- and multispectral reflectance and emission signature identification, semi-quantitative mineral abundance indicies and spectral image composites. Satellite derived supraglacial debris mineral maps displayed the predominance of layered silicates, hydroxyl-bearing and calcite minerals on Khumbu Himalayan glaciers. Supraglacial mineral maps compared with satellite thermal data revealed correlations between glacier surface composition and glacier surface temperature. Glacier velocity displacement fields and shortwave, thermal infrared false color composites indicated the magnitude of mass flux at glacier confluences. The supraglacial debris mapping methods presented in this study can be used on a broader scale to improve, supplement and potentially reduce errors associated with glacier debris radiative property, composition, areal extent and mass flux quantifications.

K. A. Casey

2012-01-01

272

Retrograde corona texture in pre-Himalayan metamorphic mafic xenoliths, Sutlej valley, NW Himalaya: Implication on rare occurrence of high-grade rocks in the Himalaya  

Science.gov (United States)

The present study documents extensive retrogression in mafic xenoliths embedded in the Kinnaur Kailash Granite (?500 Ma), Sutlej valley, NW Himalaya. Most of the mafic xenoliths are hornblende-rich and are characterized by numerous retrograde corona textures such as garnet coronae around clinopyroxene and plagioclase, titanite coronae around ilmenite, and hornblende coronae around clinopyroxene. This implies that the mafic xenoliths had undergone granulite-facies metamorphism in the early stage of metamorphic evolution, and have been extensively retrograded at a later stage to the present day amphibole-rich mafic xenoliths. The retrogression path traced by these mafic xenoliths can be constrained through P-T estimates using hbl-grt and hbl-pl geothermometry, hbl-grt-pl geobarometry, and Thermocalc3.21 calculations. The estimated results suggest temperatures in the range of 536-662 °C and pressures in the range of 4.5-6.7 kbar for the formation of the corona textures. P-T calculation of garnet forming reaction rim around clinopyroxene further shows that retrogression had started at ?650 °C and ?7.3 kbar. These observations suggest that retrogression played a major role in the obliteration of most of the high-grade pre-Himalayan xenoliths from the Himalaya.

Thakur, S. S.

2014-07-01

273

An SEM study of the nuchal organ in Daphnia himalaya (nov. sp. embryos and neonates collected from the Khumbu region (Nepalese Himalayas  

Directory of Open Access Journals (Sweden)

Full Text Available Zooplankton from the Khumbu region in Nepal are rarely studied, and little is known regarding their morphology and physiology. During the EV-K2-CNR Project, a collaboration between the Government of the Republic of Italy and the Nepal Academy of Science and Technology (NAST as part of “The long distance transport of micro-pollutants”, zooplankton samples revealed the presence of small head shields’ remains in the sediment possessing a hole in the dorsal margin. This observation led to the hypothesis that Daphnia himalaya neonates must possess a nuchal organ for osmoregulation in these alpine lakes. Here we report the presence of a nuchal organ in embryos and neonates, and explore its development, noting that the nuchal organ is retained up until the first post-embryonic moult. We also examine the chemistry of the lakes and in particular their conductivity, which is lower in lakes having D. himalaya than in lakes that do not (16 ?S and 32 ?S cm-1 respectively.

Marina MANCA

2007-08-01

274

Timing of normal faulting along the Indus Suture in Pakistan Himalaya and a case of major 231Pa/ 235U initial disequilibrium in zircon  

Science.gov (United States)

We report age data by TIMS U-Pb, LA-ICP-MS and 39Ar- 40Ar techniques for main magmatic events in the Lower Swat region of Pakistan, in order to constrain the tectonic evolution of the northwestern Himalaya. The pre-Himalayan history of the Indian continent is documented by single-zircon U-Pb results from the peraluminous Choga granite gneiss, which yielded a 468±5 Ma lower concordia intercept interpreted to approximate the time of magmatic emplacement. The presence of a well-defined 870±7 Ma inherited component (upper intercept) suggests a plutonic or volcanic protolith residing at unexposed levels of the Indian crust. Zircon data for the Swat granite gneiss from the northern part of the Loe Sar dome give an emplacement age of 267+6/-3 Ma, which is at variance with earlier correlations favoring an early Paleozoic origin. Subsequent to metamorphic overprint by the Himalayan orogeny, the Swat granite was intruded by late kinematic alkali-granite dykes. Single zircons from one of these dykes show reproducible 206Pb/ 238U data giving a precise mean age of 29.26±0.12 Ma, whereas the 207Pb/ 235U ages scatter between 34 and 81 Ma, pointing to huge and variable enrichment in 207Pb. The unsupported 207Pb can be explained by incorporation of 231Pa, an intermediate long-lived daughter nuclide in the 235U decay chain, in excess of the secular equilibrium ratio. LA-ICP-MS measurements confirm the presence of unsupported 207Pb, but do not show any correlation between the latter and other selected trace element concentrations in these zircons. A concordant Ar-Ar muscovite age of 28.4±1.1 Ma obtained for the same dyke postdates regional mica 'cooling' ages and indicates a lack of younger regional events capable of resetting the K-Ar system in muscovite. Because the dyke is pre- to synkinematic relative to normal faulting and related north-vergent folds, its emplacement age provides a maximum age for this event or reflects already ongoing local extension. A lower limit of 15 Ma has previously been established by apatite fission track analysis. The 29-15 Ma age bracket for normal faulting is coeval with extension along the South Tibetan Detachment System (STDS) on the north side of the High Himalaya. This suggests that the Indus Suture in Pakistan has acted as a western continuation of the STDS and that related faulting was roughly contemporaneous over most of the Himalaya.

Anczkiewicz, R.; Oberli, F.; Burg, J. P.; Villa, I. M.; Günther, D.; Meier, M.

2001-08-01

275

Analysis of wind speed data and wind energy potential in three selected locations in south-east Nigeria  

Energy Technology Data Exchange (ETDEWEB)

In this study, the wind speed characteristics and energy potential in selected three locations in south eastern part of Nigeria were investigated using wind speed data that span between 24 and 37 years measured at 10m height. It was shown that the annual mean wind speed at height of 10 m for Enugu, Owerri, and Onitsha are 5.42 m/s, 3.36 m/s, and 3.59 m/s, respectively, while the annual mean power densities are, respectively, 96.98 W/m2, 23.23 W/m2 and 28.34 W/m{sup 2}. It was further shown that the mean annual value of the most probable wind speed are 5.47m/s, 3.72m/s and 3.50m/s for Enugu, Owerri and Onitsha, respectively, while the respective annual value of the wind speed carrying maximum energy 6.48m/s, 4.33m/s, and 3.90m/s.The performance of selected commercial wind turbine models (with rated power between 50kW and 1000kW) designed for electricity generation and a windmill (rated power of 0.36kW) for water pumping located in these sites were examined.The annual energy output and capacity factor for these turbines as well as the water produced by the windmill were determined. The minimum required design parameters for a wind turbine to be a viable option for electricity generation in each location are also suggested. (orig.)

Oyedepo, Sunday O. [Covenant Univ., Ota, Ogun State (Nigeria). Mechanical Engineering Dept.; Adaramola, Muyiwa S. [Norwegian Univ. of Science and Technology, Trondheim (Norway). Dept. of Energy and Process Engineering; Paul, Sunday S. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Mechanical and Manufacturing Engineering

2012-07-01

276

Comparative Mutant Prevention Concentrations of Pradofloxacin and Other Veterinary Fluoroquinolones Indicate Differing Potentials in Preventing Selection of Resistance†  

Science.gov (United States)

Pradofloxacin (PRA) is an 8-cyano-fluoroquinolone (FQ) being developed to treat bacterial infections in dogs and cats. Its mutant prevention concentrations (MPC) were determined for Escherichia coli ATCC 8739 at 0.225 ?g/ml, and for Staphylococcus aureus ATCC 6538 at 0.55 ?g/ml. At drug concentrations equal to or above the MPC, growth (implying selective clonal expansion) of first-step FQ-resistant variants, naturally present in large bacterial populations, was inhibited. MPC90 derived from 10 clinical isolates each of E. coli and Staphylococcus intermedius, the latter species being of greater clinical relevance than S. aureus in companion-animal medicine, amounted to 0.2 to 0.225 and 0.30 to 0.35 ?g/ml, respectively. MPCs of other veterinary FQs were assessed to determine relative in vitro potencies. The MPCs of marbofloxacin, enrofloxacin, danofloxacin, sarafloxacin, orbifloxacin, and difloxacin were 1.2-, 1.4-, 2.3-, 2.4-, 5-, and 7-fold higher than the MPC of PRA for E. coli ATCC 8739, and 6-, 6-, 19-, 15-, 15-, and 31-fold higher than the MPC of PRA for S. aureus ATCC 6538, respectively. MPC curves revealed a pronounced heterogeneity in susceptibility within populations of ?4 × 109 CFU employed, extending to 10-fold above the MICs. The duration of incubation and, for S. aureus, inoculum density profoundly affected the MPCs. With appropriate dosing, PRA may combine high therapeutic efficacy with a high potential for restricting the selection for FQ resistance under field conditions in the species analyzed. PMID:16189094

Wetzstein, H.-G.

2005-01-01

277

Comparative mutant prevention concentrations of pradofloxacin and other veterinary fluoroquinolones indicate differing potentials in preventing selection of resistance.  

Science.gov (United States)

Pradofloxacin (PRA) is an 8-cyano-fluoroquinolone (FQ) being developed to treat bacterial infections in dogs and cats. Its mutant prevention concentrations (MPC) were determined for Escherichia coli ATCC 8739 at 0.225 microg/ml, and for Staphylococcus aureus ATCC 6538 at 0.55 microg/ml. At drug concentrations equal to or above the MPC, growth (implying selective clonal expansion) of first-step FQ-resistant variants, naturally present in large bacterial populations, was inhibited. MPC(90) derived from 10 clinical isolates each of E. coli and Staphylococcus intermedius, the latter species being of greater clinical relevance than S. aureus in companion-animal medicine, amounted to 0.2 to 0.225 and 0.30 to 0.35 microg/ml, respectively. MPCs of other veterinary FQs were assessed to determine relative in vitro potencies. The MPCs of marbofloxacin, enrofloxacin, danofloxacin, sarafloxacin, orbifloxacin, and difloxacin were 1.2-, 1.4-, 2.3-, 2.4-, 5-, and 7-fold higher than the MPC of PRA for E. coli ATCC 8739, and 6-, 6-, 19-, 15-, 15-, and 31-fold higher than the MPC of PRA for S. aureus ATCC 6538, respectively. MPC curves revealed a pronounced heterogeneity in susceptibility within populations of > or =4 x 10(9) CFU employed, extending to 10-fold above the MICs. The duration of incubation and, for S. aureus, inoculum density profoundly affected the MPCs. With appropriate dosing, PRA may combine high therapeutic efficacy with a high potential for restricting the selection for FQ resistance under field conditions in the species analyzed. PMID:16189094

Wetzstein, H-G

2005-10-01

278

Earthquake Relocation and Lateral Variation of Coda Q in Sikkim-Himalaya  

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We use data from 29 local earthquakes recorded by a network of broadband 3-component stations in Sikkim Himalaya for estimation of frequency dependent attenuation of the crust. The events range in magnitude from 3.0-5.5 and had occurred between 2005 to present. First these events are relocated using phase data from both local and regional seismograms recorded by stations within a radius of 350 km. We then use the local records of event-receiver pairs to measure the decay of coda amplitudes at a range of central frequencies (eg. 1, 2, 3, 4, 8, 10 and 12 Hz). These measurements have then been combined to estimate the frequency dependence of coda Q of the form Q(f)= Q0*f? given as: Q(f)= 123.700 × 29.301 f(0.979 × 0.038) For these 43 event-receiver pairs, the Q0 value has been observed to range from 80-200 with an average of 123.700 × 29.301 and eta ranging from 0.92 - 1.04 with an average of 0.979 × 0.038. In order to unravel the lateral variation of Q0, we regionalized the measured Q0 values by combining all the event-receiver path measurements using a back projection algorithm. In order to stabilize the inversion a nine-point spatial smoothening (similar to spatial Gaussian filter) has been applied to our dataset. Our results reveal that the Himalaya is characterized by low Q0 (80-100) values compared to the foreland basin to its south (150-200). Within the Himalaya we observe two E-W trending low Q0 regions. A comparison with the crustal structure beneath the Sikkim Himalaya reveals that the low Q0 regions correspond to the ramp on the Main Himalayan Thrust (MHT) beneath the Higher Himalaya. This is a region of high strain and profuse micro-seismicity corresponding to observed low quality factor of the crust.

Ajaay, T.; Mitra, S.

2013-12-01

279

Joint spatial variability of aerosol, clouds and rainfall in the Himalayas from satellite data  

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Full Text Available Satellite-based precipitation, Aerosol Optical Depth (AOD, Cloud Optical Depth (COD, and Aerosol Index (AI data were used to characterize the linkages among landform and the intra-annual variability of aerosols, cloudiness and rainfall in the Himalayas using Empirical Orthogonal Function (EOF analysis. The first modes of AOD and AI show the presence of two branches of dust aerosol: over the Indus River basin and the Thar Desert with a sharp west-east gradient parallel to the southern slopes of the Himalayas – the southern Branch; and the second against the slopes of the Tian Shan and over the Takla Makan Desert in the Tibetan Plateau – the northern branch. The second EOF mode of AOD accounts for about 10% of overall variance of AOD. It is attached to the foothills of the Himalayas east of the Aravalli range peaking in April-May followed by a sharp decrease between June and July during the first active phase of the monsoon. The first and second EOF modes of COD and precipitation show consistent patterns against the Central and Eastern Himalayas and along the ocean-land boundaries in western India and the Bay of Bengal. The break in cloudiness and rainfall between the winter and the monsoon seasons is captured well by the second EOF mode of COD and rainfall concurrent with the aerosol build up mode (March-April-May over the region depicted by the second mode of AOD. The results show that the Aravalli range separates the two different modes of aerosol variability over northern India with dust aerosols to the west and polluted mixed aerosols to the east consistent with its role in regional circulation and precipitations patterns as per Barros et al. (2004 and Chiao and Barros (2006. The region of spatial overlap of the modes of variability of aerosols, clouds and rainfall is captured by the second EOF of MODIS AOD along the southern slopes of the Himalayas east of the Aravalli. It is proposed that this mode maps the area where the indirect radiative effect of aerosols on cloud properties and rainfall is pronounced.

P. Shrestha

2010-02-01

280

Lower Paleozoic Continuity of the East Gondwanan Margin and Implications for Interpretation of Tectonostratigraphic Zones of the Himalaya  

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Qualitative and quantitative study of the tectonic and erosional history of the Himalayan orogen requires knowledge of the geology prior to major unroofing. Our studies of sedimentary successions in the Lesser (LH) and Tethyan Himalaya (TH)support depositional and stratigraphic continuity of the lower Paleozoic Indian Gondwanan margin across the various lithotectonic zones of the Himalaya, and along strike, from beyond the western Himalayan syntaxis in Pakistan, to Arunachal Pradesh, adjacent to the eastern syntaxis. Across-strike continuity is supported by (1) the presence of a distinctive Cambrian-Permian unconformity in the Salt Range (south of the Main Boundary Thrust), LH of India, and northern Tethyan part of Pakistan, and (2) correlative Neoproterozoic diamictite units in both the TH and LH. In addition, lithofacies changes support northward deepening across the northern Indian margin from the LH to the TH. Cambrian rocks extended south of the MBT in the Salt Range of Pakistan and are also exposed on cratonic India, south of the Himalayan Frontal Thrust in the Marwar basin of Rajasthan. Correlations indicate that the Neoproterozoic-Cambrian blanket extended far onto the Indian craton, just as on other paleocontinents at this time. Along-strike stratigraphic relationships also support the existence this extensive blanket, from which the outer Lesser Himalaya is a remnant. Similarities in stratigraphic successions, depositional ages, and geochemical deposits (e.g., phosphate) of the LH and TH between the central Himalaya and Pakistan, as well as correlative Neoproterozoic carbonate in Arunachal Pradesh (Buxa Formation), indicate that this blanket extended from west of the western syntax of the Himalaya across to the eastern syntaxis. Detrital zircon age spectra from Cambrian and Ordovician samples across the ancient northern Indian Himalayan margin show uniform signatures that include age ranges from Archean to Ordovician, with dominant of 1.3-0.9 Ga, ~0.7-0.54 Ga, and ~ 0.5 Ga peaks. New detrital zircon age data are presented for three Cambrian deposits: (1) the Tethyan Cambrian Tanawal Formation from the Peshwar Basin, Pakistan, north of the P-K Fault (=MCT), (2) cratonic Indian strata of the Tunklian Sandstone of Rajasthan, and (3) the Quartzite Formation of the Pele La Group of the Black Mountains of Bhutan. The detrital age spectra of these samples match those from Cambrian deposits across the central Himalaya. Thus, these new detrital spectra, in combination with stratigraphic data, demonstrate the continuity of lowermost Paleozoic strata along and across the Himalaya. Such continuity requires similar stratigraphic architecture in the LH, TH, and Greater Himalaya prior to Cenezoic deformation, and requires considerable removal of Neoproterozoic through Cambrian strata from the Lesser Himalaya during Himalayan uplift.

Myrow, P.; Hughes, N.; Fanning, C. M.; Banerjee, D.; Dipietro, J. A.

2009-12-01

 
 
 
 
281

Contemporary deformation in the Kashmir-Himachal, Garhwal and Kumaon Himalaya: significant insights from 1995-2008 GPS time series  

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We present new insights on the time-averaged surface velocities, convergence and extension rates along arc-normal transects in Kumaon, Garhwal and Kashmir-Himachal regions in the Indian Himalaya from 13 years of high-precision Global Positioning System (GPS) time series (1995-2008) derived from GPS data at 14 GPS permanent and 42 campaign stations between and . The GPS surface horizontal velocities vary significantly from the Higher to Lesser Himalaya and are of the order of 30 to 48 mm/year NE in ITRF 2005 reference frame, and 17 to 2 mm/year SW in an India fixed reference frame indicating that this region is accommodating less than 2 cm/year of the India-Eurasia plate motion (). The total arc-normal shortening varies between along the different transects of the northwest Himalayan wedge, between the Indo-Tsangpo suture to the north and the Indo-Gangetic foreland to the south indicating high strain accumulation in the Himalayan wedge. This convergence is being accommodated differentially along the arc-normal transects; in Lesser Himalaya and 3-4 mm/year in Higher Himalaya south of South Tibetan Detachment. Most of the convergence in the Lesser Himalaya of Garhwal and Kumaon is being accommodated just south of the Main Central Thrust fault trace, indicating high strain accumulation in this region which is also consistent with the high seismic activity in this region. In addition, for the first time an arc-normal extension of has also been observed in the Tethyan Himalaya of Kumaon. Inverse modeling of GPS-derived surface deformation rates in Garhwal and Kumaon Himalaya using a single dislocation indicate that the Main Himalayan Thrust is locked from the surface to a depth of over a width of 110 km with associated slip rate of . These results indicate that the arc-normal rates in the Northwest Himalaya have a complex deformation pattern involving both convergence and extension, and rigorous seismo-tectonic models in the Himalaya are necessary to account for this pattern. In addition, the results also gave an estimate of co-seismic and post-seismic motion associated with the 1999 Chamoli earthquake, which is modeled to derive the slip and geometry of the rupture plane.

Jade, Sridevi; Mukul, Malay; Gaur, V. K.; Kumar, Kireet; Shrungeshwar, T. S.; Satyal, G. S.; Dumka, Rakesh Kumar; Jagannathan, Saigeetha; Ananda, M. B.; Kumar, P. Dileep; Banerjee, Souvik

2014-06-01

282

Assessing the hydrologic-budget components based on field- and remote-sensing data of the Sutlej-Valley, western Himalaya.  

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The Himalaya is the source of major Asian rivers, which provide drinking water and sustain agriculture, livestock, and electricity through hydropower for hundreds of million people in the Indo-Gangetic Plain. These rivers are fed by a combination of rainfall, snowfall, and glacial melting. Liquid precipitation mainly falls during the Indian Summer Monsoon season, whereas snowfall originates form winter westerlies. Due to the remoteness of the Himalaya mountains there exist little reliable information about spatiotemporal precipitation quantities. In addition, there is virtually no comprehensive understanding of glacial melting due to the lack of mass balancing. This knowledge, however, is crucial to understand and predict the consequences of climate change in this densely populated region. In this study, we attempt to quantify the discharge components for the Sutlej River from 2001 to 2007. The Sutlej River (~55,000 km2) is the third largest river draining the Himalaya by area and receives ~50% of its annual moisture budget during winter precipitation. We combine remote-sensing data with ground measurements to calibrate and validate a hydrologic model to distinguish between the discharge components. Our distributed enhanced temperature index model captures runoff derived from rainfall, snow- and glacial melts and losses to evapotranspiration within 500x500 m grid cells. We utilize the MODerate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite to derive fractional snow cover, surface albedo, cloud cover, mean daily surface temperature, and evapotranspiration. Rainfall distribution is obtained by the Tropical Rainfall Measuring Mission (TRMM) product 2B31, which we scaled by 19 weather stations within the Sutlej catchment. We mapped glaciers by classifying snow- and cloudless Landsat ETM+ scenes and incorporated debris covered glacial tongues based on high-resolution imagery and morphological characteristics from Google Earth. We further computed global solar radiation based on a digital elevation model (SRTM) and validated it with ground data. Our study models the Sutlej River as an entity and 7 sub catchments that have varying discharge contributions. In addition, our approach is able to quantify river discharge in previously ungauged sub-catchments of the Sutlej to estimate its hydroelectric power potential.

Wulf, Hendrik; Bookhagen, Bodo; Scherler, Dirk

2010-05-01

283

12-Chemokine Gene Signature Identifies Lymph Node-like Structures in Melanoma: Potential for Patient Selection for Immunotherapy?  

Science.gov (United States)

We have interrogated a 12-chemokine gene expression signature (GES) on genomic arrays of 14,492 distinct solid tumors and show broad distribution across different histologies. We hypothesized that this 12-chemokine GES might accurately predict a unique intratumoral immune reaction in stage IV (non-locoregional) melanoma metastases. The 12-chemokine GES predicted the presence of unique, lymph node-like structures, containing CD20+ B cell follicles with prominent areas of CD3+ T cells (both CD4+ and CD8+ subsets). CD86+, but not FoxP3+, cells were present within these unique structures as well. The direct correlation between the 12-chemokine GES score and the presence of unique, lymph nodal structures was also associated with better overall survival of the subset of melanoma patients. The use of this novel 12-chemokine GES may reveal basic information on in situ mechanisms of the anti-tumor immune response, potentially leading to improvements in the identification and selection of melanoma patients most suitable for immunotherapy.

Messina, Jane L.; Fenstermacher, David A.; Eschrich, Steven; Qu, Xiaotao; Berglund, Anders E.; Lloyd, Mark C.; Schell, Michael J.; Sondak, Vernon K.; Weber, Jeffrey S.; Mulé, James J.

2012-10-01

284

Sliding wear studies of selected nitride coatings and their potential for long-term use in orthopaedic applications.  

Science.gov (United States)

In the area of orthopaedic implants, particularly total hip joint replacements, a metal-plastic combination is still the most popular choice consisting of a femoral head fabricated from 316L stainless steel, Ti alloy or Co-Cr alloy in contact with an ultra-high molecular weight polyethylene (UHMWPD) acetabular cup. It is recently considered that wear of the UHMWPE cup is of major concern. Generation of the wear debris can have adverse effects on the body, both localized and systemic. It is envisaged that wear of the prosthetic components, particularly those fabricated from UHMWPE can be reduced through the use of surface coatings. The aim of this investigation was to deposit a selection of refractory element nitride-based coatings (TiN, TiA1N, ZrN) onto 316L stainless steel substrates, using physical vapour deposition (PVD) technology and to study their sliding wear behaviour in contact with both UHMWPE and 316L stainless steel pins, using a pin-on-plate testing rig. Tests were conducted in Ringers solution and Ringers solution plus bone cement particles. The volume of material removed from the pins served as an indication of their wear behaviour. Wear mechanisms were identified using scanning electron microscopy. The results of these findings and the potential for these coatings to be used in orthopaedic applications are discussed. PMID:9769698

Ward, L P; Subramanian, C; Strafford, K N; Wilks, T P

1998-01-01

285

Characterization and Metal Detoxification Potential of Moderately Thermophilic Bacillus cereus from Geothermal Springs of Himalaya  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Two thermophilic Bacillus cereus strains (B. cereus-TA2 and B. cereus-TA4) used in the present study were isolated from the geothermal spring of Hunza valley, Gilgit, Pakistan. They showed the ability to withstand and grow at high temperature (85°C). Both these strains could resist multiple metals ( [...] copper, cadmium, mercury, manganese, zinc, arsenic, chromium and selenium). Strain B. cereus-TA4 reduced Cr (VI) at pH 5.0 to 9.0 but maximum reduction (83%) was observed at pH 7.0 after 48 h when initially supplied with 200 µg mL-1 of K2CrO4. Lower initial concentrations such as 100 µg mL-1 supported higher reduction (90 to 95%) than that of high concentration such as 500 µg mL-1 (20 to 30%). Both the strains reduced nearly 70% of Se (IV) after 48 h of growth at pH 7.0 when initially supplied with 200 µg mL-1 of Na2SeO3. The optimum temperature for maximum Se (IV) reduction was 45°C for both the strains.

Aslam Khan, Ghalib; Muhammad, Yasin; Muhammad, Faisal.

2014-07-01

286

Characterization and Metal Detoxification Potential of Moderately Thermophilic Bacillus cereus from Geothermal Springs of Himalaya  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Two thermophilic Bacillus cereus strains (B. cereus-TA2 and B. cereus-TA4) used in the present study were isolated from the geothermal spring of Hunza valley, Gilgit, Pakistan. They showed the ability to withstand and grow at high temperature (85°C). Both these strains could resist multiple metals ( [...] copper, cadmium, mercury, manganese, zinc, arsenic, chromium and selenium). Strain B. cereus-TA4 reduced Cr (VI) at pH 5.0 to 9.0 but maximum reduction (83%) was observed at pH 7.0 after 48 h when initially supplied with 200 µg mL-1 of K2CrO4. Lower initial concentrations such as 100 µg mL-1 supported higher reduction (90 to 95%) than that of high concentration such as 500 µg mL-1 (20 to 30%). Both the strains reduced nearly 70% of Se (IV) after 48 h of growth at pH 7.0 when initially supplied with 200 µg mL-1 of Na2SeO3. The optimum temperature for maximum Se (IV) reduction was 45°C for both the strains.

Aslam Khan, Ghalib; Muhammad, Yasin; Muhammad, Faisal.

287

Studies of the in vitro anticancer, antimicrobial and antioxidant potentials of selected Yemeni medicinal plants from the island Soqotra  

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Full Text Available Abstract Background Recent years have witnessed that there is a revival of interest in drug discovery from medicinal plants for the maintenance of health in all parts of the world. The aim of this work was to investigate 26 plants belonging to 17 families collected from a unique place in Yemen (Soqotra Island for their in vitro anticancer, antimicrobial and antioxidant activities. Methods The 26 plants were extracted with methanol and hot water to yield 52 extracts. Evaluation for in vitro anticancer activity was done against three human cancer cell lines (A-427, 5637 and MCF-7 by using an established microtiter plate assay based on cellular staining with crystal violet. Antimicrobial activity was tested against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains by using an agar diffusion method and the determination of MIC against three Gram-positive bacteria with the broth micro-dilution assay. Antioxidant activity was investigated by measuring the scavenging activity of the DPPH radical. Moreover, a phytochemical screening of the methanolic extracts was done. Results Notable cancer cell growth inhibition was observed for extracts from Ballochia atro-virgata, Eureiandra balfourii and Hypoestes pubescens, with IC50 values ranging between 0.8 and 8.2 ?g/ml. The methanol extracts of Acanthospermum hispidum, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia and Euphorbia socotrana also showed noticeable antiproliferative potency with IC50 values Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia, Euclea divinorum, Euphorbia socotrana, Leucas samhaensis, Leucas virgata, Rhus thyrsiflora, and Teucrium sokotranum with inhibition zones > 15 mm and MIC values ? 250 ?g/ml. In addition, the methanolic extracts of Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana and Commiphora ornifolia showed good antioxidant potential at low concentrations (more than 80% at 50 ?g/ml. Conclusion Our results show once again that medicinal plants can be promising sources of natural products with potential anticancer, antimicrobial and antioxidative activity. The results will guide the selection of some plant species for further pharmacological and phytochemical investigations.

Bednarski Patrick J

2009-03-01

288

Targeting KSHV/HHV-8 latency with COX-2 selective inhibitor nimesulide: a potential chemotherapeutic modality for primary effusion lymphoma.  

Science.gov (United States)

The significance of inflammation in KSHV biology and tumorigenesis prompted us to examine the role of COX-2 in primary effusion lymphoma (PEL), an aggressive AIDS-linked KSHV-associated non-Hodgkin's lymphoma (NHL) using nimesulide, a well-known COX-2 specific NSAID. We demonstrate that (1) nimesulide is efficacious in inducing proliferation arrest in PEL (KSHV+/EBV-; BCBL-1 and BC-3, KSHV+/EBV+; JSC-1), EBV-infected (KSHV-/EBV+; Raji) and non-infected (KSHV-/EBV-; Akata, Loukes, Ramos, BJAB) high malignancy human Burkitt's lymphoma (BL) as well as KSHV-/EBV+ lymphoblastoid (LCL) cell lines; (2) nimesulide is selectively toxic to KSHV infected endothelial cells (TIVE-LTC) compared to TIVE and primary endothelial cells (HMVEC-d); (3) nimesulide reduced KSHV latent gene expression, disrupted p53-LANA-1 protein complexes, and activated the p53/p21 tumor-suppressor pathway; (4) COX-2 inhibition down-regulated cell survival kinases (p-Akt and p-GSK-3?), an angiogenic factor (VEGF-C), PEL defining genes (syndecan-1, aquaporin-3, and vitamin-D3 receptor) and cell cycle proteins such as cyclins E/A and cdc25C; (5) nimesulide induced sustained cell death and G1 arrest in BCBL-1 cells; (6) nimesulide substantially reduced the colony forming capacity of BCBL-1 cells. Overall, our studies provide a comprehensive molecular framework linking COX-2 with PEL pathogenesis and identify the chemotherapeutic potential of nimesulide in treating PEL. PMID:21980345

Paul, Arun George; Sharma-Walia, Neelam; Chandran, Bala

2011-01-01

289

Image quality and required radiation dose for coronary computed tomography angiography using an automatic tube potential selection technique.  

Science.gov (United States)

To investigate the image quality and the minimum required radiation dose for automatic tube potential selection (ATPS) in dual-source computed tomography (DSCT) coronary computed tomography angiography (CCTA). Three hundred twenty-five consecutive patients (153 men and 172 women) undergoing CCTA were assigned to either the ATPS group (n = 172) or the control group (n = 153); the control group underwent imaging at a constant current of 120 kV. All patients were scanned in either prospectively ECG-triggered high-pitch helical mode or sequential mode. The subjective image quality score, attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), volume CT dose index (CTDIvol), and effective dose (ED) were compared between the two groups with the Student t test or Mann-Whitney U test. The subjective image quality score was not significantly different between the two groups. Imaging noise and attenuation were both significantly higher in the ATPS group than in the control group (imaging noise: 25.6 ± 7.6 versus 15.8 ± 4.0 HU, P < 0.001; attenuation: 559.6 ± 142.0 versus 412.5 ± 64.3 HU, P < 0.001). SNR and CNR were significantly lower in the ATPS group than in the control group (SNR: 23.21 ± 7.40 versus 27.71 ± 8.25, P < 0.001; CNR: 27.81 ± 8.44 versus 33.94 ± 9.69, P < 0.001). ED was significantly lower in the ATPS group than in the control group (ED: 1.25 ± 1.24 versus 2.19 ± 1.77 mSv, P < 0.001). For both groups, ED was significantly lower in the high-pitch mode than in the sequential mode. The use of ATPS for CCTA significantly reduced the radiation dose while maintaining image quality. PMID:25168405

Wang, Ying; Wang, Xiaohua; Zhang, Yan; Lu, Yuliu; Wu, Runze; Yuan, Huishu

2014-12-01

290

The Impact of Orographic Rainfall on Discharge and Erosion in the Andes and Himalaya (Invited)  

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Quantifying the degree to which tectonic and erosive processes shape landscape is key to understanding the evolution of tectonically active mountain belts. Here I explore the interplay of these two processes in the two largest orogens on Earth: The meriodionally-oriented Andes and the zonal, monsoon-soaked Himalaya. Technical advances over the past three decades have facilitated increasingly routine application of satellite-derived products to study the hydrologic budget on Earth. I use the high-resolution Tropical Rainfall Measurement Mission (TRMM) to identify rainfall distributions at a ~5x5 km2 spatial scale for the past 11 years using the platform’s precipitation radar and microwave imager. I emphasize on calibrated, mean annual and seasonal rainfall rates, but also explore single, storm-rainfall amounts in their spatiotemporal context. In order to estimate fluvial erosion, I first derive discharges by integrating rainfall over all major, mountainous catchments in the Himalaya and Andes. These water volumes in combination with channel slopes and widths are used to quantify specific stream power and steepness indices as erosion-rate proxies. For the Himalaya, I derive discharges by including a satellite derived, calibrated snow-melt model. This is important for catchments with a significant snow cover, for example in western Himalayan catchments that receive up to 50% of their annual discharge from snow melt. In an attempt to validate various stream-power based models, I compare them to new and previously published catchment-wide erosion rates derived from cosmogenic-isotope inventories. This analysis highlights the importance of orographically induced, spatially-focused rainfall on catchment-scale erosion processes.

Bookhagen, B.

2009-12-01

291

ECOLOGICAL FEATURES AND CONSERVATION OF ARNEBIA EUCHROMA. A CRITICALLY ENDANGERED MEDICINAL PLANT IN WESTERN HIMALAYA  

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Full Text Available Arnebia euchroma (Royle ex Benth. Johnston, commonly known as ‘Ratanjot’ is an important medicinal plant species and is found distributed in the western Himalaya at elevations ranging between 3200 - 4500 m above sea level. Considering its potent medicinal properties, cultural significance, declining population density and critically endangered status of this taxon, the present investigation was carried out for the assessment of its availability in the natural alpine landscapes of the Spiti cold desert of western Himalaya in Himachal Pradesh (India. We focused our study on its ecological features, population dynamics and performance in natural habitats, so as to formulate conservation plans. In order to achieve the objectives of the present study, a total of 620 areas were set by using a random sampling technique at six different locations where A. euchroma was found distributed naturally. The highest population density was recorded in undulating meadows (5.30 individuals/m2 with a maximum circumference (4.18±1.80cm at an elevation of 4240 m above sea level, with maximum frequency of occurrence (100%. Ecological surveys revealed that distribution was restricted in specific habitats rich in soil nutrients with high pH (8.025 - 8.37. The significance of the role of various ecological variables is explained in detail in the present paper. Habitat specificity, low population, and anthropogenic pressure justify the rarity status of this taxon in the Spiti valley. The authors discussed different implications to develop appropriate strategies for a long-term monitoring and sustainability of A. euchroma in the Spiti cold desert of western Himalaya.

Koushalya Nandan SINGH

2012-09-01

292

Evolution of fluvial style in the Siwalik Group in the foothills of the Nepal Himalaya  

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Middle Miocene to Pleistocene fluvial sediments of the Siwalik (Churia) Group are widely distributed in the southern frontal area of the Himalaya. The succession is about 6 km thick, and was derived from denudation of the Himalayan orogen. The Siwalik Group in Nepal is well exposed in the Surai Khola area (western Nepal), and the Hetauda-Bakiya Khola area (central Nepal). The group is separated into northern and southern belts by the Central Churia Thrust (CCT). Eight facies associations (FA1 to FA8) are recognized in the Siwalik Group in these areas. They are interpreted as the deposits of fine-grained meandering, flood-flow-dominated fine-grained meandering, sandy meandering, deep sandy braided, comparatively shallow sandy braided, anastomosed, gravelly braided, and debris-flow-dominated braided systems, respectively. FA6, FA7 and FA8 occur only in the southern belt. In each area, the sedimentary succession generally coarsens upwards. The accumulation of these facies associations, related to the paleomagnetic time frame, indicates that flooding increased dramatically from about 10.5 to 9.5 Ma, and fluvial style changed from meandering to braided between 9.0 and 6.5 Ma. A gravelly fluvial system prevailed after 3.0 to 2.5 Ma. The evolution of these fluvial styles is intimately related to the uplift of the Himalaya and associated thrust movements, and consequent effects on atmospheric circulation and precipitation. By comparison with the characteristics of the submarine Bengal Fan deposits, it is apparent that an increase in flood flow is strongly influenced by increased precipitation due to onset and intensification of monsoon climate. The sandy braided system was mainly induced by regional tectonic uplift, and the gravelly fluvial system may have been formed due to regional thrust movements along the Himalaya frontal area.

Nakayama, Katsuhiro; Ulak, Prakash D.

1999-05-01

293

Size Analysis of the Late Pliocene-Early Pleistocene Upper Siwalik Sediments, Northwestern Himalaya, India  

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Full Text Available Size analysis of the Late Pliocene-Early Pleistocene Upper Siwalik sediments comprising the Pinjor Formation in the type area and adjoining regions reveals that the sediments are bimodal to polymodal in nature, medium to fine grained and are moderately sorted. The inclusive graphic standard deviation and moment standard deviation values suggest the deposition of sediments in shallow to moderately deep fluvial agitated water. The log probability plots reveal that saltation mode is the dominant mode of transportation of detritus. The sediments are continental in character and are derived from crystalline, metamorphic and sedimentary rocks of the Himalaya exposed to the North of the type area Pinjor.

Mahavir Singh

2013-10-01

294

Chemical characteristics of pond waters within the debris area of Lirung Glacier in Nepal Himalaya  

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Water samples were analyzed from ponds developed within the debris-covered area of Lirung Glacier (28º 12.9’N, 86º 39.9’E; 4000 m a.s.l.) in the Himalayas of Nepal during the pre-monsoon to post-monsoon period of 1996. Major chemical species were classified into three groups based on their relationships relative to the sum of cations: conservative (SiO2, Ca2+, K+, and Alkalinity), semiconservative (Na+, Mg2+, and SO4 2-) and non-conservative (NH4 +, NO3 - and Cl-). The dominant processe...

Takeuchi, Nozomu; Yamamoto, Mineko; Masuzawa, Toshiyuki; Bhatt, Maya P.

2007-01-01

295

Glacier changes in the Garhwal Himalaya, India, from 1968 to 2006 based on remote sensing  

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Glacier outlines are mapped for the upper Bhagirathi and Saraswati/Alaknanda basins of the Garhwal Himalaya using Corona and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite images acquired in 1968 and 2006, respectively. A subset of glaciers was also mapped using Landsat TM images acquired in 1990. Glacier area decreased from 599.9 ± 15.6 km2 (1968) to 572.5 ± 18.0 km2 (2006), a loss of 4.6 ± 2.8%. Glaciers in the Saraswati/Alaknanda basin and upper Bhagira...

Bhambri, R.; Bolch, T.; Chaujar, R. K.; Kulshreshtha, S. C.

2011-01-01

296

Vertical Deformation in the Himalaya and Tibet Constrained by GPS and GRACE Measurements  

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Significant seasonal signals appear in both GPS and GRACE measurements for the Himalaya and Tibet region. We investigate the vertical seasonal variation and its impact on vertical velocity estimates with combined GPS and GRACE observations. First, we use the seasonal variations of GRACE-derived load change to model their resulting seasonal vertical deformation for the continuous GPS stations in this area. The quantitative comparisons between observed and modeled seasonal detrended vertical timeseries show very good agreements between these two kinds of geodetic measurements. The general correlation between GPS and GRACE indicates the possibility of correcting GPS seasonal effects using GRACE timeseries. With this method we can study the impacts of seasonal variation on vertical rates estimates, and better constrain the vertical velocities for campaign GPS measurements within this region, for which the seasonal effects are usually difficult to eliminate. The derived GPS vertical rates are able to better reveal the vertical motions in the Himalaya and Tibet. In addition to the seasonal oscillations, GRACE also indicates a long-term trend due to the mass transportation. Especially in the Himalayan area, melting mountain ice and snow results in substantial mass loss. The earth, as an elastic body, will uplift as a response to the load decrease. So the hydrological effects mix in the observed GPS timeseries, and possibly bring biases to tectonic deformation. If we ignore GIA's influence, and quantify the elastic uplifts at the continuous GPS stations due to the GRACE-derived load loss, we can remove those uplifts from observed GPS vertical velocity fields. We believe the residuals should be mainly attributed to the tectonic process. In the Himalaya region, the Main Himalaya Thrust (MHT) fault underthrusts beneath the Eurasian plate. We use a simplified 2D displacement model to interpret the GPS observed vertical rates, in which the uplift due to mass loss has been removed. Our results indicate that the vertical velocities for most GPS sites in Nepal can be well modeled by interseismic slip of MHT, few exceptions indicates some local effect may exist.

Fu, Y.; Freymueller, J. T.

2011-12-01

297

Snow and glacier change in koshi Basin Himalaya and its response to global warming  

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Recently, the argument that Himalayan glaciers will completely melt is rather controversial and the U.N.'s leading panel on climate change has apologized for misleading data published in a 2007 report that warned Himalayan glaciers could melt by 2035. Why the gradual melting of Himalayan glaciers makes most of the major media headlines? This is because Himalayan glacier is the headstream of major rivers in South Asia and Southeast Asia and more than 1/6 people live there. If mass of the glaciers melt or even disappear, people who rely on those rivers will be at risk. After this dispute, we need to realize that:”Although the melting rate still need to further study, the Himalayan glaciers are indeed melting. And in these areas, there are more uncertainties to affect water resource, such as snow fall, precipitation, regional temperature changes and so on”. Koshi Basin Himalaya, located in the boundary between China and Nepal, consist of three rivers i.e. Sun Koshi, Arun river (the headwaters of arun river in China called Pengqu) and Tamur. All of them converge to India Ganga River. The total area of Koshi Basin is about ~57,870 km2 and elevation ranges from 21 m (plain) to 8825m (Mountain glacier). This basin has the typical vertical zonation of Himalaya, so we choose it as the study area. Based on the snow cover data observed by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the NASA Terra spacecraft from 2000-2010, the spatial-temporal distribution and variation of snow cover over the koshi basin are statistical analyzed. Glacier changes are also detected from Landsat images in 2000, 2005 and 2010. It is found that snow cover areas are mainly concentrated in the Ridge of Himalaya Mountain. And there are more persistently snow covered areas and glaciers in the South Slope of Himalaya Mountain with aspect to the North Slope, although the mean elevation of the North Slope is higher than south slope. During the decade of 2000-2010, a slight decreasing trend is present although annual change is different. Furthermore, temperature data from 2000-2010 obtained by in-situ station and MODIS are used to get the regional warming trend and obtain the relationship between glacier, snow decrease and temperature increase. Primary results indicate that snow is sensitive to the seasonal change of temperature while glacial change is affected by the general trend of temperature change.

Gao, Y.; Yang, X.; Yao, T.; Yufeng, D.

2010-12-01

298

Medicinal flora and ethnoecological knowledge in the Naran Valley, Western Himalaya, Pakistan  

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Full Text Available Abstract Background Mountain ecosystems all over the world support a high biological diversity and provide home and services to some 12% of the global human population, who use their traditional ecological knowledge to utilise local natural resources. The Himalayas are the world's youngest, highest and largest mountain range and support a high plant biodiversity. In this remote mountainous region of the Himalaya, people depend upon local plant resources to supply a range of goods and services, including grazing for livestock and medicinal supplies for themselves. Due to their remote location, harsh climate, rough terrain and topography, many areas within this region still remain poorly known for its floristic diversity, plant species distribution and vegetation ecosystem service. Methods The Naran valley in the north-western Pakistan is among such valleys and occupies a distinctive geographical location on the edge of the Western Himalaya range, close to the Hindu Kush range to the west and the Karakorum Mountains to the north. It is also located on climatic and geological divides, which further add to its botanical interest. In the present project 120 informants were interviewed at 12 main localities along the 60 km long valley. This paper focuses on assessment of medicinal plant species valued by local communities using their traditional knowledge. Results Results revealed that 101 species belonging to 52 families (51.5% of the total plants were used for 97 prominent therapeutic purposes. The largest number of ailments cured with medicinal plants were associated with the digestive system (32.76% responses followed by those associated with the respiratory and urinary systems (13.72% and 9.13% respectively. The ailments associated with the blood circulatory and reproductive systems and the skin were 7.37%, 7.04% and 7.03%, respectively. The results also indicate that whole plants were used in 54% of recipes followed by rhizomes (21%, fruits (9.5% and roots (5.5%. Conclusion Our findings demonstrate the range of ecosystem services that are provided by the vegetation and assess how utilisation of plants will impact on future resource sustainability. The study not only contributes to an improved understanding of traditional ethno-ecological knowledge amongst the peoples of the Western Himalaya but also identifies priorities at species and habitat level for local and regional plant conservation strategies.

Khan Shujaul M

2013-01-01

299

The role of microphysical processes on the mesoscale simulation over the complex terrain, the Himalayas  

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The objective of this study is to evaluate the impact of the four different cloud microphysical schemes (WSM3, WSM6, Morrison double moment and Lin scheme) within the Weather Research and Forecasting model (WRF), as part of simulations of mesoscale weather systems across complex terrain in the Nepalese Himalayas. The Himalayas is characterized by a complex and rugged topography, with altitudes varying e.g. 70m in Southeastern Nepal, to the highest peak of the world, 8850m (Mt. Everest), and which extends from West to East covering many South and Central Asian countries: Afghanistan, Pakistan, China, India, Nepal, Bhutan, and Myanmar. Circulation in such a complex environment is complicated due to obstruction of flows by mountain ranges which in turn have wide ranging effects on cloud and rain formation and distribution. Monsoon rain is intrinsically linked to people’s daily life across the South Asia since more than 80% people depend on agriculture and majority of the agricultural systems are rainfall dependent. Modeling of the key microphysical process in this complex terrain provides insight into the general understanding of the processes and their spatial patterns, however there are many uncertainties in general. These uncertainties are even more pronounced when such models are applied to the complex terrain characteristic of the Himalayas. Numerical experiments are designed using the WRF model, with three nested domains (27, 9 and 3 km grid spacing). The performance of the four categories of microphysical schemes is examined in model experiments for (i) monsoon onset, (ii) monsoon decay and (iii) winter rainfall. The simulated results are compared with limited observed meteorological parameters such as rainfall, temperature, wind speed and wind direction, from ground-based meteorological stations situated within the high resolution (3km x 3km) domain. Results show that a) Simulated rainfall is very sensitive to the chosen microphysical scheme with rainfall spatial and temporal characteristics being very different for each scheme. However, the majority of the WRF simulations showed similar general patterns with monsoon onset and subsequent maturation across the Southeast region of Nepal which then gradually moves Northwest over time before dissipating; b) It was found that strong moist convection caused by near surface convergence of wind is responsible for producing significant nocturnal maximum precipitation during the monsoon period. All the WRF simulations revealed that the continuous southerly moist monsoonal flow interacting with the South slope of the Himalayas and associated diurnal variation of ambient atmospheric state is the major cause of the nocturnal maximum rain generally across the region; c) The WSM6 microphysical scheme performed relatively better than the other schemes.

Shrestha, R. K.; Gallagher, M. W.; Connolly, P.

2010-12-01

300

Joint spatial variability of aerosol, clouds and rainfall in the Himalayas from satellite data  

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Full Text Available Satellite-based precipitation, Aerosol Optical Depth (AOD, Cloud Optical Depth (COD, and Aerosol Index (AI data were used to characterize the linkages among landform and the intra-annual variability of aerosols, cloudiness and rainfall in the Himalayas using empirical orthogonal function (EOF analysis. The first modes of AOD and AI show the presence of two branches of dust aerosol: over the Indus river basin and the Thar desert with a sharp west-east gradient parallel to the southern slopes of the Himalayas – the Southern Branch; and the second against the slopes of the Tian Shan and over the Takla Makan desert in the Tibetan Plateau-the Northern branch. The third EOF mode of AOD accounts for about 7% of overall variance of AOD. It is attached to the foothills of the Himalayas east of the Aravalli range peaking in April-May-June followed by a sharp decrease in July during the first active phase of the monsoon. The first and second EOF modes of COD and precipitation show consistent patterns against the central and eastern Himalayas and along the ocean-land boundaries in western India and the Bay of Bengal. The break in cloudiness and rainfall between the winter and the monsoon seasons is captured well by the second EOF mode of COD and rainfall concurrent with the aerosol build up mode (April–May over the region depicted by the third mode of AOD. The results show that the Aravalli range separates the two different modes of aerosol variability over northern India with dust aerosols to the west and polluted mixed aerosols to the east consistent with its role in regional circulation and precipitations patterns as per Barros et al. (2004 and Chiao and Barros (2007. SVD analysis between rainfall, COD and AOD showed a pattern of aerosol loading (resembling EOF3 of MODIS AOD extending from 80° E~90° E that peaks during the winter and pre-monsoon seasons and decays abruptly during the monsoon: the regions of aerosol buildup during the pre-monsoon season and the areas of high rainfall/cloudiness during the monsoon are collocated and have opposite signs suggesting aerosol-cloud-rainfall interaction. It is proposed that the third EOF of AOD maps the area where aerosol-cloud-rainfall interactions play an important role in the regional hydro-climatology.

P. Shrestha

2010-09-01

 
 
 
 
301

Event-Related Potentials (ERPs) in Second Language Research: A Brief Introduction to the Technique, a Selected Review, and an Invitation to Reconsider Critical Periods in L2  

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This article provides a selective overview of recent event-related brain potential (ERP) studies in L2 morpho-syntax, demonstrating that the ERP evidence supporting the critical period hypothesis (CPH) may be less compelling than previously thought. The article starts with a general introduction to ERP methodology and language-related ERP profiles…

Steinhauer, Karsten

2014-01-01

302

The Discovery of Potentially Selective Human Neuronal Nitric Oxide Synthase (nNOS Inhibitors: A Combination of Pharmacophore Modelling, CoMFA, Virtual Screening and Molecular Docking Studies  

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Full Text Available Neuronal nitric oxide synthase (nNOS plays an important role in neurotransmission and smooth muscle relaxation. Selective inhibition of nNOS over its other isozymes is highly desirable for the treatment of neurodegenerative diseases to avoid undesirable effects. In this study, we present a workflow for the identification and prioritization of compounds as potentially selective human nNOS inhibitors. Three-dimensional pharmacophore models were constructed based on a set of known nNOS inhibitors. The pharmacophore models were evaluated by Pareto surface and CoMFA (Comparative Molecular Field Analysis analyses. The best pharmacophore model, which included 7 pharmacophore features, was used as a search query in the SPECS database (SPECS®, Delft, The Netherlands. The hit compounds were further filtered by scoring and docking. Ten hits were identified as potential selective nNOS inhibitors.

Guanhong Xu

2014-05-01

303

Improvement of Sexual Destination in Atropa acuminata Royle (Solanaceae-A Critically Endangered Medicinal Plant of Northwestern Himalaya  

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Full Text Available Good seed set is no guarantee of absolute sexual destination in plants. Seed viability and seed vigour are crucial phases in the life cycle of every sexually reproducing plant. The present study was an attempt to improve the sexual destination-the germination and seedling survival of Atropa acuminata Royle (Solanaceae, an endemic and extremely restricted sub-alpine medicinal plant of North West Himalayas under ex situ conditions at (1580 m with an aim to develop a successful germination protocol and agrotechnique in order to revegetate disturbed areas. Among various treatments given to the seeds, GA3, Scarification, warm water treatment and chilling at 4°C for 90 days were found to be most effective with percentage germination of 73.3±18.80, 79.95±9.40, 66.6±6.6, 45±7.07 (X±SE, respectively. The results reveal that the seeds do not germinate unless specific environmental signals or events occur which trigger the genetic and hormonal response of the seeds thereby facilitating their germination. The diversity and the extent of the dormancy mechanisms encountered here suggest that under harsh conditions, natural selection may favour seeds with a genetic system for dormancy and delayed germination. A relation was observed between seed size/weight,%age germination and subsequent seedling survival. Seedling survival is also effected by specific habitat requirement and stiff intra and inter-specific competition particularly the whimsical behaviour of Sambucus wigthiana (an alien species which grows in the vicinity of Atropa is beyond the ken of Atropa, adding fuel to the already burning candle apart from habitat fragmentation and herbivory.

Parvaiz A. Wani

2007-01-01

304

F 11440, a potent, selective, high efficacy 5-HT1A receptor agonist with marked anxiolytic and antidepressant potential.  

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F 11440 (4-methyl-2-[4-(4-(pyrimidin-2-yl)-piperazino)-butyl]-2H, 4H-1,2,4-triazin-3,5-dione) was the outcome of a research effort guided by the hypothesis that the magnitude of the intrinsic activity of agonists at 5-HT1A receptors determines the magnitude of their antidepressant and anxiolytic-like effects. The affinity of F 11440 for 5-HT1A binding sites (pKi, 8.33) was higher than that of buspirone (pKi, 7.50), and somewhat lower than that of flesinoxan (pKi, 8.91). In vivo, F 11440 was 4- to 20-fold more potent than flesinoxan, and 30- to 60-fold more potent than buspirone, in exerting 5-HT1A agonist activity at pre- and postsynaptic receptors in rats (measured by, for example, its ability to decrease hippocampal extracellular serotonin (5-HT) levels and to increase plasma corticosterone levels, respectively). F 11440 did not have detectable antidopaminergic activity (unlike buspirone, which inhibited all of the directly observable behavioral effects of methylphenidate in rats), showed no evidence of antihistaminergic activity (unlike flesinoxan, which protected against the effects of a histamine aerosol in guinea pigs), and had a 70-fold separation between its 5-HT1A agonist and alpha-1 adrenergic antagonist properties (measured as the ability to inhibit the methoxamineinduced increase in blood pressure in rats), unlike flesinoxan, which showed a <3-fold separation. In HeLa cells expressing human 5-HT1A receptors, F 11440 decreased the forskolin-induced increase in AMP, and, based on its maximal effect, was found to have an intrinsic activity of 1.0 relative to that of 5-HT, which was significantly higher than that of buspirone (0.49), ipsapirone (0.46) and flesinoxan (0.93). Consistent with the aforementioned hypothesis, F 11440 produced anxiolytic- and antidepressant-like effects in animal models (i.e., increased punished responding in a pigeon conflict procedure and decreased immobility in a rat forced swimming test, respectively) that were more substantial than those of buspirone, ipsapirone and flesinoxan. Thus, F 11440, shown here to be a potent, selective, high efficacy 5-HT1A receptor agonist, appears to have the potential to exert marked anxiolytic and antidepressant activity in humans. PMID:9765347

Koek, W; Patoiseau, J F; Assié, M B; Cosi, C; Kleven, M S; Dupont-Passelaigue, E; Carilla-Durand, E; Palmier, C; Valentin, J P; John, G; Pauwels, P J; Tarayre, J P; Colpaert, F C

1998-10-01

305

Instrument-free control of the standard potential of potentiometric solid-contact ion-selective electrodes by short-circuiting with a conventional reference electrode.  

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A simple, instrument-free method to control the standard potential (E°) of potentiometric solid-contact ion-selective electrodes (SC-ISE) is described. In this method, the electrode potential of a SC-ISE is reset by short-circuiting the electrode with a metallic wire to a conventional Ag/AgCl/3 M KCl reference electrode (RE) in a solution containing primary ions. The method is studied experimentally for SC-ISEs where the conducting polymer poly(3,4-ethylenedioxythiophene) doped with the bulky anion poly(sodium 4-styrenesulfonate), PEDOT(PSS), is used as the solid contact. Three different types of ion-selective membranes (ISMs) are studied: two potassium-selective membranes, with and without the lipohilic additive tetradodecylammonium tetrakis(4-chlorophenyl)borate (ETH-500) and a cation-sensitive membrane without an ionophore. When the SC-ISE is short-circuited with the RE, the PEDOT(PSS) layer is oxidized or reduced, thereby shifting the potential of the SC-ISE to the proximity of the potential of the RE so that the potential difference between these two electrodes becomes zero or close to zero. The slope of the calibration curve is preserved after the short-circuit treatment of the SC-ISEs. The short-circuiting method is an important step toward calibration-free potentiometric analysis. PMID:25284311

Vanamo, Ulriika; Bobacka, Johan

2014-11-01

306

Identification and conservation of important plant areas (IPAS) for the distribution of medicinal, aromatic and economic plants in the Hindukush-Himalaya mountain range  

International Nuclear Information System (INIS)

s. In order to contribute to the specified target, WHO advised the relevant institutions to develop research plans and conservation programmes that are focused on the Global strategy in general and target 5 in specific. While complementing the appeal and contributing to its vision, a study was conducted in various eco-systems of the Pakistan's Hindukush-Himalayas region, identifying Important Plant Areas (IPAs) for their subsequent conservation and uses for scientific purposes. Site selection for the study was based on: 1). Exceptional vegetation richness for the representative bio-geographic zone; 2). Presence of naturally occurring medicinal herbs with species of global or regional concern, and (3). Threatened habitats that are supporting plant species of medicinal and economic values. Apart from various values of the selected sites such as their scientific and economic importance, the selected sites had a treasure of indigenous knowledge related to the wise uses and conservation of medicinal plants. The study also focused on exploring the complex natural interactions between plants and other organisms; their dependence under various environmental parameters; traditional knowledge of the local inhabitants; and the significance of the landscape to Conserve such plants on long-term basis. (author)

307

Molybdenum Isotopic evidence of anoxia at Permo-Triassic boundary from Spiti Valley Himalaya  

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Permo-Triassic (PT) extinction was the most devastating event in the history of life on Earth which occurred around 251 Ma ago. The exact cause of extinction remains uncertain. To understand the cause of extinction, we studied the redox sensitive elements, sulfur and Mo isotopes from the PT section of Spiti valley of Himalaya, India. In Spiti valley, 1-10 cm of ferruginous band of sediments separates the Permian shale from Triassic limestone. Analyses of redox sensitive elements such as As, Mo, As, Ni, Sb, Th, Mn and Fe show clear evidence of anoxia or euxinia. Here we present molybdenum abundance and isotopes analysis of PT sedimentary section which has potential to distinguish between sulfidic deep water (Euxinia), suboxic and oxic conditions. Mo is redox sensitive and the most abundant transition metal in present day ocean. It enters the ocean through rivers (?98/95Mo~ 0‰) and remains in the water as moderately unreactive MoO4-- form. Under the oxidizing marine conditions similar to present day, Mo from water column is slowly removed by incorporation into ferromanganese phases with preferential removal of lighter Mo isotopes (?98/95Mo ~-0.7‰). As a result, the ocean water is enriched in heavier isotope (?98/95Mo ~2.3‰). However, in euxinic conditions with sulfidic deep water ([H2S]>100?M), Mo is quantitatively removed from the solution as MoS4-- without isotopic fractionation. Therefore Mo isotopic composition of sediments deposited under these conditions represents the Mo composition of water. Earlier studies of different PT sections showed prevalence of anoxic or euxinic condition during P-T transition, therefore the Mo isotope analysis of PT sediments should let us know about extent of anoxia at the Spiti site which was open towards and well connected to super-ocean during end Permian. Mo concentration in the PT sedimentary section from Spiti showed clear enrichment with Mo content of 77 ppm at the boundary with ?98/95Mo value of 0.75‰. Whereas the average concentration of Mo are 0.7 ppm and 1.7 ppm observed for above and below the boundary with corresponding mean ?98/95Mo values of 0.7‰ and -0.5‰. The enrichment of Mo abundance is accompanied by rapidly fluctuating ?98/95Mo in four samples from the boundary which first reduced to -0.2‰ followed by an increase to 0.75‰ in LIN-1P-C. This followed by another decrease in ?98/95Mo to 0.1‰ . Very high concentration of Mo in boundary samples clearly demonstrate sulfidic condition at PT which is also consistent with inferences drawn with other redox sensitive elements measured in this section. Fluctuation in ?98/95Mo in the boundary samples are mainly due to reservoir effect where most of the ocean become anoxic and verylimited Mo remains into water. Therefore our results suggest that euxinic condition was prevailed during end Permian extinction and release of H2S from ocean to atmosphere might be the responsible for this greatest extinction of life

Rai, V. K.; Shukla, A. D.; Kamath, S.

2013-12-01

308

Spatial Distribution of Thermal Properties on Debris-Covered Glaciers in the Himalayas Derived From ASTER Data  

Science.gov (United States)

The rapid retreat of Himalayan glaciers generates moraine-dammed glacial lakes which have potential to cause Glacial Lake Outburst Floods (GLOFs). Glacial lakes are generally at different evolutionary stages even under the same climatic conditions. Such evolutionary processes are not well studied due to difficulties in field observations. The present study investigates thermal resistances on the debris-covered glaciers around Mt. Everest and Lunana region in Bhutan using satellite images taken by ASTER. The thermal resistance is defined as thickness divided by thermal conductivity of a debris layer, and is an essential thermal property for evolution of glacial lakes through melting process. Assuming a linear temperature profile within a debris layer and a bottom temperature of 0 degree Celsius, the conductive heat term in a heat balance equation can be expressed as a surface temperature divided by the thermal resistance. The conductive heat can be obtained from net radiation which is a dominant energy source on the Himalayan glaciers. The net radiation is calculated by combining downward radiation fluxes of NCEP/NCAR reanalysis data with the surface temperature and albedo which are obtained from ASTER data. Then the thermal resistance can be calculated from the net radiation and the surface temperature. The result shows that the thermal resistances on 10 glaciers among 25 target glaciers without lakes are twice as large as the mean of thermal resistances of 7 target glaciers with lakes. Spatial characteristics of thermal resistances are also identified; large increases appear toward glacier termini on glaciers without lakes, whereas relatively small and uniform values appear along those with lakes. These results imply that the different patterns and magnitudes in thermal properties on debris-covered glaciers are related to different evolutionary stages of glacial lakes in the Himalayas. Furthermore, the present study demonstrates that ASTER data provide valuable information for glacial lake studies.

Suzuki, R.; Fujita, K.; Ageta, Y.

2006-12-01

309

Time series of glacier frontal variations in the Nanga Parbat region, Western Himalaya  

Science.gov (United States)

Global trends of glacier response in many mountain environments suggest extensive backwasting and downwasting patterns, with some recent acceleration in the last few decades. Glaciers in the Western Himalaya are perhaps more complicated than other regions due to their complex topography, extensive supraglacial debris cover, and climate system coupling involving the winter westerlies, Indian summer monsoon and possibly the East Asian monsoon. Consequently, we investigated glacier retreat/advance pattern of ten major glaciers in and around the Nanga Parbat massif. Specifically, we used high-quality topographic maps, and Keyhole, SPOT, Landsat and ASTER satellite imageries from 1934-2010. Our results indicate no uniform response of these glaciers to climate change. Some glaciers are retreating and/or maintaining their frontal position whereas others have advanced at different time periods. Average retreat rates, however, are not nearly as large as those reported in the nearby region, and average advance rates are not surge-type. Glacier advances in this region have neither been reported as surge-type glaciers in the past, nor have shown surge-type patterns; therefore, these advances may be due to positive mass balance, or could be an indication of major dynamical change in future. Overall, results indicate that Nanga Parbat glaciers are oscillating and may be responding differently to the current climatic conditions than in the eastern Himalaya (east of the study area), or the Wakhan Pamir/Hindu Kush (northwest of the study area), or Tien Shan region (north of the study area).

Haritashya, U. K.; Bishop, M. P.; Kargel, J. S.; Leonard, G. J.; Shroder, J. F.

2011-12-01

310

Diet of Threatened Pheasant Species in Himalayas, India – A Faecal Analysis Approach  

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Full Text Available The aim of this paper is to determine diet composition of threatened pheasant species i.e. Satyr Tragopan Tragopan satyra, Himalayan Monal Lophophorus impejanus, Kaleej Lophura leucomelana and Koklass Pucrasia macrolopha in their native forest which was never studied earlier. A study was conducted in the Kumaon region of western Himalaya for two years by collecting dropping material. Faeces were identified through direct sighting of defecating species. The diet items of each pheasant species mainly comprised plant materials followed by invertebrates and grit. A significant difference was observed in consuming food items by all pheasant species. Monal emerged as a specialist feeder on plants which were not eaten by other species. The Satyr and Koklass were more similar in terms of diet composition in both seasons while Kaleej and Monal were least similar, only invertebrates and grit were common in the diet of these species. No significant difference was observed in diet composition in different seasons of all pheasant species. The results expected to provide valuable information for the management of these pheasants in Himalayas.

Mohammad Shah Hussain

2013-06-01

311

Fluid driven earthquakes in the Chamoli Region, Garhwal Himalaya: evidence from local earthquake tomography  

Science.gov (United States)

The Chamoli region, within the ˜700 km seismic gap of the seismically active region of the Central Himalaya, has been site of moderate sized earthquakes in recent past, viz. 1999 March 29 (Mb 6.3), 2005 December 14 (Mb 5.3), and very recently 2011 June 20 (M 4.6). To understand the process of earthquake generation in the region, we constrain earthquake distribution pattern and determine the crustal seismic wave velocity variation using local earthquake data recorded by the Kumaon-Garhwal Himalaya seismic network that was operated during 2005-2008. Also, we included aftershocks data from the 1999 Chamoli earthquake. We infer that the earthquakes are mainly clustered near the Munsiary Thrust marking the southern part of the Main Central Thrust zone and in depth, above the Main Himalayan Thrust. The Chamoli earthquake source region is characterized by low P-wave velocity (VP) and high VP/VS. This could be expression of possible presence of fluids because of metamorphic dehydration reaction by the underthrusting Indian crust. The released fluid percolates upwards into the brittle portion of the crust, reducing the fault zone friction leading to generation of crustal earthquakes.

Mahesh, P.; Gupta, Sandeep; Rai, S. S.; Sarma, P. Rajagopala

2012-12-01

312

Snowfall less sensitive to warming in Karakoram than in Himalayas due to a unique seasonal cycle  

Science.gov (United States)

The high mountains of Asia, including the Karakoram, Himalayas and Tibetan Plateau, combine to form a region of perplexing hydroclimate changes. Glaciers have exhibited mass stability or even expansion in the Karakoram region, contrasting with glacial mass loss across the nearby Himalayas and Tibetan Plateau, a pattern that has been termed the Karakoram anomaly. However, the remote location, complex terrain and multi-country fabric of high-mountain Asia have made it difficult to maintain longer-term monitoring systems of the meteorological components that may have influenced glacial change. Here we compare a set of high-resolution climate model simulations from 1861 to 2100 with the latest available observations to focus on the distinct seasonal cycles and resulting climate change signatures of Asia's high-mountain ranges. We find that the Karakoram seasonal cycle is dominated by non-monsoonal winter precipitation, which uniquely protects it from reductions in annual snowfall under climate warming over the twenty-first century. The simulations show that climate change signals are detectable only with long and continuous records, and at specific elevations. Our findings suggest a meteorological mechanism for regional differences in the glacier response to climate warming.

Kapnick, Sarah B.; Delworth, Thomas L.; Ashfaq, Moetasim; Malyshev, Sergey; Milly, P. C. D.

2014-11-01

313

Nannofossil biostratigraphy of the Lower Cretaceous Shadui Formation (Northern Tethyan Himalayas, Southern Tibet)  

Science.gov (United States)

Calcareous nannofossils of Aptian-Albian age were found in the basal part of the Shadui Formation, Northern Tethyan Himalayas, Southern Tibet. The predominantly shale strata are exposed near the northeastern tip of Yamdrock Tso Lake at the locality of Bangbu and they were previously considered to be of Late Cretaceous age. Occurrence of the nannofossil species Prediscosphaera columnata and Cribrosphaerella ehrenbergii indicates the Upper Aptian-Lower Albian Zone BC23. Nannofossil species of Late Albian, Cenomanian or younger Cretaceous age were not present in the studied part of the Shadui Formation. Nannofossils are badly preserved and hardly identifiable probably as a result of strong post mortem etching and dissolution during burial. The depositional setting of the Shadui Formation is interpreted as hemipelagic to pelagic. A horizon of dark shale in the lower part of the Shadui Formation may be stratigraphically correlated with ocean anoxic event OAE1b. The discovery of calcareous nannofossils at the Bangbu locality increases the stratigraphic precision in the correlation of Cretaceous strata between hemipelagic-pelagic facies and shelf depositional areas in the Tibetan Tethyan Himalayas.

Švábenická, Lilian; Li, Xianghui; Jansa, Lubomír F.; Wei, Yushuai

2010-10-01

314

High altitude dives from 7000 to 14,200 feet in the Himalayas.  

Science.gov (United States)

Indian Navy divers carried out no-decompression dives at altitudes of 7000 to 14,200 ft (2134-4328 m) in the Nilgiris and Himalayas from May to July 1988. Seventy-eight dives on air and 22 dives on oxygen were carried out at various altitudes. The final dives were at Lake Pangong Tso (4328 m) in Ladakh, Himalayas, to a maximum of 140 feet of sea water (fsw) [42.6 meters of sea water (msw)] equivalent ocean depth in minimum water temperature of 2 degrees C. Oxygen diving at 14,200 ft (4328 m) was not successful. Aspects considered were altitude adaptation, diminished air pressure diving, hypothermia, and remote area survival. Depths at altitude were converted to depths at sea level and were applied to the Royal Navy air tables. Altitude-related manifestations, hypoxia, hypothermia, suspected oxygen toxicity, and equipment failure were observed. It is concluded that stress is due to effects of altitude and cold on man and equipment, as well as changes in diving procedures when diving at high altitudes. Equivalent air depths when applied to Royal Navy tables could be considered a safe method for diving at altitudes. PMID:1887518

Sahni, T K; John, M J; Dhall, A; Chatterjee, A K

1991-07-01

315

Planktonic Desmid Flora of South of the Eastern Himalayas: A Systematic Approach on Algae-I  

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Full Text Available Desmids are freshwater algae often considered as indicator of oligotrophic environment for water bodies. There are ample examples of works done by various workers throughout the world. Though desmids are reported from many parts of India, North East India, located in South of the Eastern Himalaya, is lacking behind in the study of this particular microflora in spite of its rich biodiversity. Therefore, an attempt has been made to study the planktonic desmid flora of North East India. Samples are collected with the help of planktonic net, wide mouth bottles and natural periphytons. Species are identified with the help of standard literature. In the present investigation, a total no. of 38 taxa of desmids including 8 species of genera Closterium, 10 species of Cosmarium, 5 species of Euastrum, 5 species of Micrasterias, 1 species of Netrium, Tortitaenia and Gonatozygon, 2 species of Pleurotaenium and 5 species of Staurastrum were recorded as phytoplankton during August 2009 to 2010 which are new records from the South of the Eastern Himalayas. Among them Closterium and Cosmarium are found to be more abundant indicating their oligotrophic nature which are need to be conserved.

K.K. Medhi

2011-01-01

316

Analysis of climatic variability and snow cover in the Kaligandaki River Basin, Himalaya, Nepal  

Science.gov (United States)

Various remote sensing products and observed data sets were used to determine spatial and temporal trends in climatic variables and their relationship with snow cover area in the higher Himalayas, Nepal. The remote sensing techniques can detect spatial as well as temporal patterns in temperature and snow cover across the inaccessible terrain. Non-parametric methods (i.e. the Mann-Kendall method and Sen's slope) were used to identify trends in climatic variables. Increasing trends in temperature, approximately by 0.03 to 0.08 °C year-1 based on the station data in different season, and mixed trends in seasonal precipitation were found for the studied basin. The accuracy of MOD10A1 snow cover and fractional snow cover in the Kaligandaki Basin was assessed with respect to the Advanced Spaceborne Thermal Emission and Reflection Radiometer-based snow cover area. With increasing trends in winter and spring temperature and decreasing trends in precipitation, a significant negative trend in snow cover area during these seasons was also identified. Results indicate the possible impact of global warming on precipitation and snow cover area in the higher mountainous area. Similar investigations in other regions of Himalayas are warranted to further strengthen the understanding of impact of climate change on hydrology and water resources and extreme hydrologic events.

Mishra, Bhogendra; Babel, Mukand S.; Tripathi, Nitin K.

2014-05-01

317

Traditional use of medicinal plants among the tribal communities of Chhota Bhangal, Western Himalaya  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract The importance of medicinal plants in traditional healthcare practices, providing clues to new areas of research and in biodiversity conservation is now well recognized. However, information on the uses for plants for medicine is lacking from many interior areas of Himalaya. Keeping this in view the present study was initiated in a tribal dominated hinterland of western Himalaya. The study aimed to look into the diversity of plant resources that are used by local people for curing various ailments. Questionnaire surveys, participatory observations and field visits were planned to illicit information on the uses of various plants. It was found that 35 plant species are commonly used by local people for curing various diseases. In most of the cases (45% under ground part of the plant was used. New medicinal uses of Ranunculus hirtellus and Anemone rupicola are reported from this area. Similarly, preparation of "sik" a traditional recipe served as a nutritious diet to pregnant women is also not documented elsewhere. Implication of developmental activities and changing socio-economic conditions on the traditional knowledge are also discussed.

Jamwal Pankaj

2006-03-01

318

A CERN flag is set to wave up in the Himalayas  

CERN Multimedia

On 18 October, Hubert Reymond, from the Industrial Controls and Engineering group of the EN Department, will be leaving to Nepal with a CERN flag in his backpack. He will place it at the highest point of his trek across the Annapurna mountains in the Himalayas, Thorong La pass, at 5,416 m above sea level.   A view of the Annapurna mountains (source: www.flickr.com/minutesalone) “Is there any official CERN flag I can carry with me during my trek through Nepal?” Some days ago, the Press Office was confronted with this unusual (but see box) question from Hubert Reymond. From 18 October to 10 November, Reymond, who works as an industrial computing engineer in the EN Department, will be trekking across the 55 km-long Annapurna massif in the Himalayas, whose highest point lies at 8,091 m (making it the 10th-highest summit in the world). The area is well-known to trekkers from around the world, as it includes several world-class circuits, including the Annapurna circuit which Reym...

Roberto Cantoni

2010-01-01

319

Southern limits of major earthquake ruptures along the Himalaya between longitudes 75° and 90°E  

Science.gov (United States)

The ruptures responsible for major earthquakes along the Himalayan Convergent Plate Margin (HCPM) occur in a strikewise oriented zone of frictional failure and relative slip in a buried detachment along the upper surface of the Indian Shield rocks subducting under the Himalaya. The southern limit of the rupture zone is a geotectonic lineament whose geographic location is important in assessing risk due to earthquakes. A major part of this article is taken up in arguing that the available macroseismic and instrumental evidence for the 1934 Bihar-Nepal earthquake is consistent with the view that the rupture which caused it occurred in the detachment mostly under the Lesser Himalaya northward from the vicinity of the surface trace of the Main Boundary Thrust (MBT). Since a similar location has been inferred by others for the 1905 Kangra earthquake rupture, a basis arises for postulating that, over more than half of the length of the HCPM between 75% and 90° E longitudes, the ruptures responsible for major earthquakes lie in the detachment with their southern limits geographically similarly close to the surface trace of the MBT. This includes the nearly 700 km long seismic gap between the 1905 and 1934 ruptures.

Chander, Ramesh

1989-12-01

320

Elemental and individual particle analysis of atmospheric aerosols from high Himalayas.  

Science.gov (United States)

Atmospheric aerosols were collected during the scientific expedition to Mt. Qomolangma (Everest) in May-June, 2005. The elemental concentrations of the aerosols were determined by inductively coupled plasma mass spectrometry. This yielded data for the concentration of 14 elements: Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Pb. The mean elemental concentrations were generally comparable with those from central Asia and the Arctic, while much higher than those from Antarctic. Size, morphology, and chemical composition of 900 individual aerosol particles were determined by scanning electron microscopy and energy-dispersive X-ray microanalysis. Based on morphology and elemental composition, the particles were clustered into eight groups: soot (8%), tar ball (3%), alumosilicates/silica (55%), calcium sulfate (16%), Ca/Mg carbonate (2%), Fe/Ti-rich particles (3%), Pb-rich particles (1%), and biological particles (12%). The sampling site, located at 6,520 m in the Himalayas, is particularly remote and located at high altitude. Nonetheless, high aerosol enrichment factors for copper, chromium, lead, nickel, vanadium, and zinc all suggest the influence of long-range transported pollution, while enrichment in calcium and the presence of alumino-silicates in individual particle analyses indicates a distinct mineral dust influence. The backward air mass trajectories showed that the northwestern part of India may contribute to the atmospheric aerosol in the central high Himalayas. PMID:19083111

Cong, Zhiyuan; Kang, Shichang; Dong, Shuping; Liu, Xiande; Qin, Dahe

2010-01-01

 
 
 
 
321

A novel method of selecting human embryonic stem cell-derived cardiomyocyte clusters for assessment of potential to influence QT interval.  

Science.gov (United States)

Physiologically relevant assessment of delayed repolarization is necessary in drug development. In our preliminary experiments on the evaluation using a multielectrode recording system, we had found that the responsiveness of field potential duration (FPD), as QT-like intervals, to hERG channel blockers differed greatly from non-responders to excessive responders in human embryonic stem cell-derived cardiomyocyte clusters. Thus, we report a novel method of selecting clusters suitable for evaluating compounds for the assessment. Clusters were treated with cisapride, a hERG channel blocker, at 100nM, and selected with criteria of 5-20% of corrected FPD (FPDc) prolongation. Then, selected clusters were treated with reference compounds. FPDc was prolonged by blockade of the hERG channel (E-4031 and dl-sotalol) and KvLQT1 channel (chromanol 293B and HMR1556), and by activation of the sodium channel (veratridine) and calcium channel (Bay K8644). FPDc was shortened by calcium channel blockage (verapamil, nifedipine and diltiazem) and by K(ATP) channel activation (pinacidil). Class Ia antiarrhythmic drugs, quinidine and disopyramide, prolonged FPDc. Selected clusters are appropriate for assessing the effects of compounds on ion channels affecting QT intervals. This is the first report of the establishment of an assessment system of potential to influence QT interval, using pharmacologically selected clusters. PMID:22198052

Yamazaki, Kazuto; Hihara, Taro; Taniguchi, Tomohiko; Kohmura, Naohiro; Yoshinaga, Takashi; Ito, Masashi; Sawada, Kohei

2012-03-01

322

Selection of candidate container materials for the conceptual waste package design for a potential high level nuclear waste repository at Yucca Mountain  

Energy Technology Data Exchange (ETDEWEB)

Preliminary selection criteria have been developed, peer-reviewed, and applied to a field of 41 candidate materials to choose three alloys for further consideration during the advanced conceptual design phase of waste package development for a potential high level nuclear waste repository at Yucca Mountain, Nevada. These three alloys are titanium grade 12, Alloy C-4, and Alloy 825. These selections are specific to the particular conceptual design outlined in the Site Characterization Plan. Other design concepts that may be considered in the advanced conceptual design phase may favor other materials choices.

Van Konynenburg, R.A.; Halsey, W.G.; McCright, R.D.; Clarke, W.L. Jr. [Lawrence Livermore National Lab., CA (United States); Gdowski, G.E. [KMI, Inc., Albuquerque, NM (United States)

1993-02-01

323

Towards reducing the physical environmental impact of North American surface coal mines; a review of potential selective overburden handling techniques  

Energy Technology Data Exchange (ETDEWEB)

In North America, coal and lignite are presently extracted by a variety of surface mining techniques that are largely dictated by factors such as coal thickness and attitude, overburden characteristics, and geological complexity of the deposit. Although a large variety of techniques are used, they are often similar within certain geographic regions, each being associated with a typical method of overburden handling and one or more major type(s) of physical environmental impact (topographic, stratigraphic and/or geohydrologic). While it is technically feasible to modify current routine overburden handling practices, or to introduce effective novel selective handling techniques in order to reduce subsequent environmental damage within each geographic region, economic factors do not always favour selective methods. Because of the possibility of increased stripping costs, the implementation of any selective overburden placement scheme requires site-specific appraisal of the profitability of the operation. In some situations, however, the use of selective techniques in place of conventional methods can actually be economically superior. The appropriate selective overburden placement schemes that can be applied in the different geographic regions are assessed. 8 figs., 24 refs., 2 tabs. (F.W.)

George, H. (Queen' s Univ., Kingston, Ontario (Canada)); Meech, J.; Workman, L.

1986-01-01

324

Impact of initial and boundary conditions on regional winter climate over the Western Himalayas: A fixed domain size experiment  

Science.gov (United States)

The Western Himalayas during winter receives precipitation due to the eastward moving low pressure synoptic weather systems, called Western Disturbances (WDs) in Indian meteorological parlance. The complex Himalayan topography, sparse observational data, less understanding of physical processes, etc. form many interesting research questions over this region. One of the important research goals is to study the change in the winter (Dec., Jan. and Feb. - DJF) climate over the Himalayas. In the presented study with modelling efforts having varying initial and boundary conditions (ICBC) with same model physics option is attempted to provide a comment on important physical processes pertaining to precipitation and temperature fields. A 22 year (1980-2001) simulation with Regional Climate Model version 3 (RegCM3) forced with National Centre for Environmental Prediction/National Centre for Atmospheric Research (NCEP/NCAR) reanalysis 1 (NNRP1), NCEP/NCAR reanalysis 2 (NNRP2) and European Centre for Medium Range Weather Forecast 40 Year reanalysis (ERA40) as three different ICBC is carried out. The present study focuses on the winter climatology of the main meteorological parameters viz., temperature, precipitation and snow depth and interannual variability of winter seasonal precipitation. The model shows overestimation of seasonal average precipitation and underestimation of seasonal average temperature fields over the Western Himalayas in all the three model simulations. The interannual variability of precipitation and temperature over this region is nicely captured by the model. The model simulation with NNRP2 as the ICBC shows more realistic results. In addition the ensemble mean of the three simulations has shown improved results and is closer to the abovementioned simulation. Precipitation bias explained in terms of the higher vertical integrated moisture flux and transport shows strong convergence zone over and along the southern rim of the Indian Himalayas. The energy balance over the Western Himalayas explains the cause of lower temperature in the model simulation and the cause of lesser convective precipitation and evaporation.

Maharana, P.; Dimri, A. P.

2014-03-01

325

Transport of sediments in Himalaya-Karakorum and its influence on hydropower plants; Sedimenttransportprozesse im Himalaya-Karakorum und ihre Bedeutung fuer Wasserkraftanlagen  

Energy Technology Data Exchange (ETDEWEB)

In the present study the sediment transport processes in alpine mountain areas and their impact on hydropower development projects are investigated. The aim of the present work is to contribute to the understanding of the transport process system, which is characterized by high magnitude-low frequency - events, to ensure an appropriate layout of high head hydropower projects in mountain regions. The sediment transport in large areas in the macro scale is triggered by natural hazards, such as earthquakes, rock slides, earth movements, debris flows, glacial lake outbursts and floods. The basic principle of complex transport processes in this scale is described and explained on the example of the Himalaya-Karakorum-region. The sediment transport process in the smaller scale, so called meso scale, is investigated by means of extensive field measurements at river reaches of 16 different mountain rivers of a 80000 km{sup 2} large project area. The measurements include topographic survey works and measurements of discharge, bed load and suspended load. Since the conditions of mountain rivers in terms of size of bed material as well as available flow velocities can be considered as extreme, an appropriate bed load sampler named B-69 was developed, constructed and used in the field. Moreover the hydraulic as well as the sedimentological efficiency of the sampler was tested in the laboratory tests. Due to the nice performance of the bed load sampler B-69 at high flow velocities it might be useful for flood conditions in gravel-bed rivers in other parts of the world as well. Based on the results of the study the parameter of the river slope can be considered as the most important one for the characteristics of the morphology, the flow conditions, the bed stability as well as the bed load transport in steep mountain rivers. With increasing slope morphological structures in the longitudinal direction will develop from flat bed conditions. The so called step-pool-systems consist of a cascade of staircase local falls. Their distance in-between the falls as well as their height difference at the steps is strongly depending on the river slope. (orig.) [German] Die vorliegende Arbeit beschaeftigt sich mit den Sedimenttransportprozessen in alpinen Gebirgsregionen und deren Auswirkungen auf Wasserkraftanlagen. Ziel der Arbeit ist es, zum Verstaendnis des natuerlichen Sedimenttransportes mit der fuer Gebirgsregionen typischen Charakteristik von 'High Magnitude-Low Frequency - Prozessen' beizutragen, um eine den Transportverhaeltnissen geeignete Auslegung von geplanten Wasserkraftanlagen zu finden. Am Beispiel der Gebirgsregion des Himalaya-Karakorums werden die komplexen Transportvorgaenge im grossraeumigen Raum des Makromassstabes erlaeutert. Dabei wird auf die Massentransporte eingegangen, die durch Naturgefahren wie Erdbeben, Felsgleitungen, Erdrutsche, Muren, Gletscherbrueche und Hochwaesser ausgeloest werden. Der Schwerpunkt der Arbeit liegt in der Durchfuehrung von umfangreichen Naturmessungen im untergeordneten Raum des Mesomassstabes im Bereich von einzelnen Flussabschnitten. Die Naturmessungen umfassen morphologische und topographische Aufnahmen, Abfliessmessungen, Geschiebe- sowie Schwebstoffmessungen an 16 Gebirgsfluessen eines insgesamt 80000 km{sup 2} grossen Projektgebietes im Himalaya-Karakorum. Aufgrund der extremen Verhaeltnisse der Gebirgsfluesse der Region hinsichtlich vorhandener Korngroesse des Bettmaterials sowie die Groessenordnung der Fliessgeschwindigkeiten wurde fuer die Untersuchungen eigens der mobile Geschiebesammler B-69 entwickelt, gebaut und auf seine hydraulische und sedimentologische Effizienz hin geprueft. Der Einsatz des B-69 hat sich im Feld bewaehrt und ist fuer weitere Anwendungen bei Hochwasserereignissen in kiesfuehrenden Fluessen geeignet. Als massgebender Parameter zur Beschreibung der Morphologie, der Stroemung, der Sohlenstabilitaet und des Geschiebetransportes von Gebirgsfluessen im Mesomassstab konnte das Gefaelle I festgestellt werden. Das Gefaelle ist bestimmend fuer die Ausbildung d

Palt, S.M.

2001-07-01

326

AN ANALYSIS OF MARKET POTENTIAL ANALYSIS TOWARDS SMALL CAR SEGMENT WITH SPECIAL REFERENCE TO SELECTED CITIES IN TAMILNADU  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years small segment cars became more popular due to its low price and its attractive features. In Indian market the small segment cars have more welcome from all the parts of India. This research was carried to found the market potential to the small car industry in India For this study the structured questionnaire was carried and the study concluded with the 600 respondents. It shows that market potential for the small car segment in Indian consumers overwhelm and Indian customers are the potential buyers to the small car segment.

V.SUBRAMANIAN

2013-01-01

327

The staurosporine-like compound L-753,000 (NB-506) potentiates the neurotrophic effects of neurotrophin-3 by acting selectively at the TrkA receptor.  

Science.gov (United States)

K-252b, a member of the staurosporine family of protein kinase inhibitors, selectively potentiates the activation of the nerve growth factor receptor, TrkA, by a nonpreferred ligand, neurotrophin-3 (NT-3), in a variety of cell types. At higher (micromolar) concentrations of K-252b, an inhibitory effect occurs because of the inhibitory action of K-252b on the Trk kinase. By examining analogs of K-252b, we identified the compound L-753,000 (NB-506), which potentiates the action of NT-3 on TrkA but is devoid of the inhibitory action of K-252b. L-753,000 was effective at nanomolar concentrations in a Chinese hamster ovary cell line that expressed TrkA but was devoid of p75, the low-affinity neurotrophin receptor. L-753,000 also potentiated the activation of mitogen-activating protein kinase signaling (downstream from Trk activation) by NT-3 in this cell line. Although L-753,000, like K-252b, had a negligible effect in the absence of NT-3, the compound was found to potentiate NT-3-induced survival in both rat and chick primary cultures of dissociated dorsal root ganglia (DRG) and on neurite outgrowth of chick DRG explants. Unlike K-252b, which at micromolar concentrations inhibits the survival response of NT-3 in dissociated rat DRG, L-753,000 continued to potentiate the actions of NT-3 up to a concentration of 10 microM. Furthermore, the compound, unlike K-252b, did not inhibit an unrelated protein kinase, protein kinase C, at concentrations up to 10 microM. Because L-753, 000 selectively potentiates the NT-3-induced stimulation of TrkA without inhibiting Trks and other protein kinases, it represents a novel class of selective modifiers of neurotrophin actions. PMID:10385700

Pollack, S; Young, L; Bilsland, J; Wilkie, N; Ellis, S; Hefti, F; Broughton, H; Harper, S

1999-07-01

328

76 FR 27342 - Central Utah Project Completion Act; Notice of Intent To Accept Proposals, Select a Potential...  

Science.gov (United States)

...development of environmentally sustainable hydropower potential on Federal...Power Administration, 150 Social Hall Avenue, Suite 300...and under CUPCA has certain responsibilities and obligations for the CUP...operation and maintenance responsibility for the CUP...

2011-05-11

329

Testing of Selected Workplace Chemicals for Teratogenic Potential with Attachments, Cover Sheets and Letter dated 02/25/81.  

Science.gov (United States)

The reproductive toxicity and teratogenic potential of 19 industrial chemicals have been investigated during the past 3 years. Preliminary studies in rats, utilizing intraperitoneal treatments on days 1-15 of gestation, have been conducted on 10 chemicals...

1981-01-01

330

Divergence with gene flow in a population of thermophilic bacteria: a potential role for spatially varying selection.  

Science.gov (United States)

A fundamental goal of evolutionary biology is to understand how ecological diversity arises and is maintained in natural populations. We have investigated the contributions of gene flow and divergent selection to the distribution of genetic variation in an ecologically differentiated population of a thermophilic cyanobacterium (Mastigocladus laminosus) found along the temperature gradient of a nitrogen-limited stream in Yellowstone National Park. For most loci sampled, gene flow appears to be sufficient to prevent substantial genetic divergence. However, one locus (rfbC) exhibited a comparatively low migration rate as well as other signatures expected for a gene experiencing spatially varying selection, including an excess of common variants, an elevated level of polymorphism and extreme genetic differentiation along the gradient. rfbC is part of an expression island involved in the production of the polysaccharide component of the protective envelope of the heterocyst, the specialized nitrogen-fixing cell of these bacteria. SNP genotyping in the vicinity of rfbC revealed a ~5-kbp region including a gene content polymorphism that is tightly associated with environmental temperature and therefore likely contains the target of selection. Two genes have been deleted both in the predominant haplotype found in the downstream region of White Creek and in strains from other Yellowstone populations of M. laminosus, which may result in the production of heterocysts with different envelope properties. This study implicates spatially varying selection in the maintenance of variation related to thermal performance at White Creek despite on-going or recent gene flow. PMID:24863904

Wall, Christopher A; Koniges, Gregory J; Miller, Scott R

2014-07-01

331

Low- and intermediate level radioactive waste from Risoe, Denmark. Location studies for potential disposal areas. Report no. 1. Data, maps, models and methods used for selection of potential areas  

International Nuclear Information System (INIS)

The low and intermediate level radioactive waste from Risoe (the nuclear reactor buildings plus different types of material from the research periods) and radioactive waste from hospitals and research institutes have to be stored in a final disposal in Denmark for at least 300 years. The Minister for Health and Prevention presented the background and decision plan for the Danish Parliament in January 2009. All political parties agreed on the plan. The investigation of geological deposits as potential waste disposals for high radioactive waste from nuclear power plants has earlier focused on deep seated salt deposits and basement rocks. Nevertheless, the Tertiary clays were mapped as well. In the present study, the salt diapirs and the salt deposits are not included. The present report briefly describes the existing data collections (including databases, maps and models), that are used during the work of selection of ca. 20 potentially suitable areas. Most of the information is stored in GEUS databases: Location of boreholes, borehole data, rock sediment and ground water compounds, maps, geophysical data and much more, but information is also collected from other institutions. The methods are described in more details (chapter 6) and this description is the direct background for the selection process, the characterisation of the 20 areas and for the final selection of the 2 or 3 most potential sites. (LN)

332

Low- and intermediate level radioactive waste from Risoe, Denmark. Location studies for potential disposal areas. Report no. 1. Data, maps, models and methods used for selection of potential areas  

Energy Technology Data Exchange (ETDEWEB)

The low and intermediate level radioactive waste from Risoe (the nuclear reactor buildings plus different types of material from the research periods) and radioactive waste from hospitals and research institutes have to be stored in a final disposal in Denmark for at least 300 years. The Minister for Health and Prevention presented the background and decision plan for the Danish Parliament in January 2009. All political parties agreed on the plan. The investigation of geological deposits as potential waste disposals for high radioactive waste from nuclear power plants has earlier focused on deep seated salt deposits and basement rocks. Nevertheless, the Tertiary clays were mapped as well. In the present study, the salt diapirs and the salt deposits are not included. The present report briefly describes the existing data collections (including databases, maps and models), that are used during the work of selection of ca. 20 potentially suitable areas. Most of the information is stored in GEUS databases: Location of boreholes, borehole data, rock sediment and ground water compounds, maps, geophysical data and much more, but information is also collected from other institutions. The methods are described in more details (chapter 6) and this description is the direct background for the selection process, the characterisation of the 20 areas and for the final selection of the 2 or 3 most potential sites. (LN)

Gravesen, P.; Nilsson, B.; Schack Pedersen, S.A.; Binderup, M.

2011-07-01

333

Macro Invertebrate Community from Sonamarg Streams of Kashmir Himalaya  

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Full Text Available This study analyses a macroinvertebrate community survey for River Sindh and its tributary including Baltal, Yashmarg, Sonamarg and Thajwas Grar considering the extreme hydrological conditions linked with the seasonal low-flow period typical for some streams in this area. This study attempts to provide an overview of the macro invertebrate assemblages and physico-chemical variables of the River Sindh and its important tributary. Four study sites were selected from the River Sindh and its tributary including Baltal, Yashmarg, Sonamarg and Thajwas Grar for studying the ecological distribution of Macroinvertebrate assemblages. Totally, 33 taxa of macroinvertebrates were recorded from the two streams belonging to Mollusca-3 (Gastropoda-2 and Bivalvia-1, Annelida-1 and Arthropoda-29 (Insecta-29. Among insects Ephemeroptera (7, Trichoptera (6 and Diptera (13 dominated. Except Yashmrag all sites were found devoid of annelids while as the mollusks were found absent at Sonamarg. Highest values of Shannon Weiner Index were found at Yashmarg (2.42 and lowest at Sonamarg (1.99 while as highest and lowest Sorensen?s similarity coefficient were found between Baltal/Thajwas Grar (0.68 and Yashmarg/Thajwas Grar (0.39, respectively. A perusal of the data on physico-chemical characteristics showed that these streams were hard water type with high dissolved oxygen content. The ionic composition of the stream waters revealed the predominance of bicarbonate and calcium. Insecta dominated both qualitatively as well as quantitatively and the study revealed that the substrate compositions dominated by gravel, pebble and leaf litters are primary determinants of the invertebrate community structure recording maximum species diversity and abundance. Sample locations impacted by Amarnath yatris pilgrimage comparatively reflected slightly higher increase in nutrients than Thajwas Grar almost devoid of pilgrimage effect.

A.R. Yousuf

2011-01-01

334

Modelling glacier change in the Everest region, Nepal Himalaya  

Science.gov (United States)

In this study, we apply a glacier mass balance and ice redistribution model to simulate historical and future glacier change in the Everest region of Nepal. High-resolution temperature and precipitation fields derived from gridded APHRODITE data, and validated against independent station observations from the EVK2CNR network, are used to drive the historical model from 1961 to 2007. The model is calibrated against geodetically derived estimates of net glacier mass change from 1992 to 2008, termini position of four large glaciers at the end of the calibration period, average velocities observed on selected debris-covered glaciers, and total glacierized area. We integrate field-based observations of glacier mass balance and ice thickness with remotely-sensed observations of decadal glacier change to validate the model. Between 1961 and 2007, the mean modelled volume change over the Dudh Kosi basin is -6.4 ± 1.5 km3, a decrease of 15.6% from the original estimated ice volume in 1961. Modelled glacier area change between 1961 and 2007 is -101.0 ± 11.4 km2, a decrease of approximately 20% from the initial extent. Scenarios of future climate change, based on CMIP5 RCP4.5 and RCP8.5 end members, suggest that glaciers in the Everest region will continue to lose mass through the 21st century. Glaciers in the basin are concentrated between 5000 and 6000 m of elevation, and are thus expected to be sensitive to changes in temperature and equilibrium line altitude (ELA). Glacier volume reductions between -35 to -62% are possible by 2050, and sustained temperature increases to 2100 may result in total glacier volume losses of between -73 and -96%.

Shea, J. M.; Immerzeel, W. W.; Wagnon, P.; Vincent, C.; Bajracharya, S.

2014-10-01

335

Shilajit: A Natural Phytocomplex with Potential Procognitive Activity  

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Shilajit is a natural substance found mainly in the Himalayas, formed for centuries by the gradual decomposition of certain plants by the action of microorganisms. It is a potent and very safe dietary supplement, restoring the energetic balance and potentially able to prevent several diseases. Recent investigations point to an interesting medical application toward the control of cognitive disorders associated with aging, and cognitive stimulation. Thus, fulvic acid, the main active principle...

Carlos Carrasco-Gallardo; Leonardo Guzmán; Maccioni, Ricardo B.

2012-01-01

336

Determination of the jump in electrostatic potential at the earth's bow shock front by selective measurements of the ion components in the solar wind  

International Nuclear Information System (INIS)

We have examined the jumps in velocity and temperature of the proton and alpha-particle components in the solar wind when the wind intersects the Earth's bow shock. The jumps were measured by means of selective detectors of the SKS energy spectrometer on the satellites Prognoz 7 and 8. On the basis of energy balance, we determine the jump in the electrostatic potential at the shock front: on the average, it amounts to about 300 V

337

Antecedence of the Yarlung-Siang-Brahmaputra River, eastern Himalaya  

Science.gov (United States)

At the eastern terminus of the Himalayan orogen, distortion and capture of southeast Asian drainage basins reflects regional patterns of crustal strain due to the indentation of the Indian Plate into Eurasia. After flowing eastward >1000 km along the southern margin of Tibet, the Yarlung-Siang-Brahmaputra River turns abruptly southward through the eastern Himalayan syntaxis rapidly exhuming a crustal scale antiform in an impressive >2 km knickpoint. This conspicuous drainage pattern and coincidence of focused fluvial incision and rapid rock exhumation has been explained by the capture of an ancestral, high-elevation Yarlung River by headward erosion of a Himalayan tributary. However, recent observation of Tibetan detritus in Neogene foreland basin units complicates this explanation, requiring a connection from Tibet to the foreland prior to the estimated onset of rapid rock exhumation. We constrain the sedimentary provenance of foreland basin units deposited near the Brahmaputra River confluence in the eastern Himalayan foreland basin using detrital zircon U-Pb geochronology. We interpret the significant presence of Gangdese-age detritus in each foreland basin unit to indicate that connection of the Yarlung-Siang-Brahmaputra River was established during, or prior to foreland deposition in the Early Miocene. Our results indicate that connection of the Yarlung-Siang-Brahmaputra River precedes exhumation of the syntaxis, demonstrating the potential for the progressive coevolution of rock uplift and rapid erosion of the Namche Barwa massif.

Lang, Karl A.; Huntington, Katharine W.

2014-07-01

338

Toxin-based in-vitro selection and its potential application to date palm for resistance to the bayoud Fusarium wilt.  

Science.gov (United States)

Date palm (Phoenix dactylifera L.) is qualified as a 'tree' of great ecological and socio-economical importance in desert oases. Unfortunately, it is being decimated, especially in Morocco and Algeria, by a fusariosis wilt called bayoud and caused by Fusarium oxysporum f. sp. albedinis (Fao). Controlling this disease requires the implementation of an integrated management program. Breeding for resistance is one of the most promising component strategies of this program. Few naturally resistant cultivars with a mediocre fruit quality (dates) are known. Conventional and non-conventional methods are under development and have to use the simplest and easiest methods to screen for resistant individuals. The use of pathogen toxins as selective agents at the tissue culture step might be a source of variability that can lead to the selection of individuals with suitable levels of resistance to the toxin and/or to the pathogen among the genetic material available. Foa produces toxins such as fusaric, succinic, 3-phenyl lactic acids and their derivatives, marasmins and peptidic toxins. These toxins can be used bulked or separately as selective agents. The aim of this contribution was to give a brief overview on toxins and their use as a mean to select resistant lines and to initiate a discussion about the potential use of this approach for the date palm-Foa pathosystem. This review does not pretend to be comprehensive or exhaustive and was prepared mainly to highlight the potential use of Foa toxins for selecting date palm individuals with a suitable resistance level to bayoud using toxin-based selective media. PMID:16125651

El Hadrami, Abdelbasset; El Idrissi-Tourane, Abdelmalek; El Hassni, Majida; Daayf, Fouad; El Hadrami, Ismaïl

2005-08-01

339

Tapping the translation potential of cAMP signalling: molecular basis for selectivity in cAMP agonism and antagonism as revealed by NMR.  

Science.gov (United States)

Eukaryotic CBDs (cAMP-binding domains) control multiple cellular functions (e.g. phosphorylation, guanine exchange and ion channel gating). Hence the manipulation of cAMP-dependent signalling pathways has a high translational potential. However, the ubiquity of eukaryotic CBDs also poses a challenge in terms of selectivity. Before the full translational potential of cAMP signalling can be tapped, it is critical to understand the structural basis for selective cAMP agonism and antagonism. Recent NMR investigations have shown that structurally homologous CBDs respond differently to several CBD ligands and that these unexpected differences arise at the level of either binding (i.e. affinity) or allostery (i.e. modulation of the autoinhibitory equilibria). In the present article, we specifically address how the highly conserved CBD fold binds cAMP with markedly different affinities in PKA (protein kinase A) relative to other eukaryotic cAMP receptors, such as Epac (exchange protein directly activated by cAMP) and HCN (hyperpolarization-activated cyclic-nucleotide-modulated channel). A major emerging determinant of cAMP affinity is hypothesized to be the position of the autoinhibitory equilibrium of the apo-CBD, which appears to vary significantly across different CBDs. These analyses may assist the development of selective CBD effectors that serve as potential drug leads for the treatment of cardiovascular diseases. PMID:24646235

Boulton, Stephen; Akimoto, Madoka; VanSchouwen, Bryan; Moleschi, Kody; Selvaratnam, Rajeevan; Giri, Rajanish; Melacini, Giuseppe

2014-04-01

340

Transpiration and CO/sub 2/ fixation of selected desert shrubs as related to soil-water potential  

Energy Technology Data Exchange (ETDEWEB)

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species (Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.) as the soil-moisture potential decreased are given. With a mesic species, H. annuus, 20% reduction in photosynthesis and transpiration was reached at higher soil-moisture potentials than with the desert plants. Loss of net photosynthesis occurred in A. dumosa (a summer deciduous shrub) as PSI soil reached -48 bars in the field, whereas L. tridentata (an evergreen shrub) at the same time was able to maintain a water potential difference between soil and plant of -10 to -15 bars and continue net CO/sub 2/ gain well into the summer months.

Clark, S.B.; Letey, J. Jr.; Lunt, O.R.; Wallace, A.; Kleinkopf, G.E.; Romney, E.M.

1980-01-01