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Sample records for bow mountains southeastern

  1. Drill-hole data, drill-site geology, and geochemical data from the study of Precambrian uraniferous conglomerates of the Medicine Bow Mountains and Sierra Madre of southeastern Wyoming

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    Karlstrom, K.E.; Houston, R.S.; Schmidt, T.G.; Inlow, D.; Flurkey, A.J.; Kratochvil, A.L.; Coolidge, C.M.; Sever, C.K.; Quimby, W.F.

    1981-02-01

    This volume is presented as a companion to Volume 1: The Geology and Uranium Potential of Precambrian Conglomerates in the Medicine Bow Mountains and Sierra Madre of Southeastern Wyoming; and to Volume 3: Uranium Assessment for Precambrian Pebble Conglomerates in Southeastern Wyoming. Volume 1 summarized the geologic setting and geologic and geochemical characteristics of uranium-bearing conglomerates in Precambrian metasedimentary rocks of southeastern Wyoming. Volume 3 is a geostatistical resource estimate of U and Th in quartz-pebble conglomerates. This volume contains supporting geochemical data, lithologic logs from 48 drill holes in Precambrian rocks of the Medicine Bow Mountains and Sierra Madre, and drill site geologic maps and cross-sections from most of the holes.

  2. Sustainable Development in Mountain Regions: Southeastern Europe, and Sustainable Mountain Regions: Challenges and Perspectives in Southeastern Europe

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    Martin F. Price

    2016-08-01

    Full Text Available Reviewed: Sustainable Development in Mountain Regions: Southeastern Europe Edited by Georgi Zhelezov. Cham, Switzerland: Springer, 2016. xiv + 404 pp. Hardcover: US$ 129.00, ISBN 978-3-319-20109-2. E-book: US$ 99.00, ISBN 978-3-319- 20110-8. Reviewed: Sustainable Mountain Regions: Challenges and Perspectives in Southeastern Europe Edited by Boian Koulov and Georgi Zhelezov. Cham, Switzerland: Springer, 2016. xvi + 268 pp. Hardcover: US$ 129.00, ISBN 978-3-319-27903-9. E-book: US$ 99.00, ISBN 978-3-319-27905-3.

  3. Extinct mountain goat ( Oreamnos harringtoni) in Southeastern Utah

    Science.gov (United States)

    Mead, Jim I.; Agenbroad, Larry D.; Phillips, Arthur M.; Middleton, Larry T.

    1987-05-01

    The extinct Harrington's mountain goat ( Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce ( Picea engelmannii), limber pine ( Pinus flexilis), rose ( Rosa cf. woodsii), and Douglas fir ( Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper ( Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch ( Betula) is determined from pollen clumps in dung pellets.

  4. Bowing in the Right Direction: Hiland Mountain Correctional Center Women's String Orchestra Programme

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    Warfield, Duane

    2010-01-01

    The Hiland Mountain Correctional Center, a 400-bed facility for multi-level adult female offenders in Eagle River, Alaska, offers a unique educational programme to its prisoners: an orchestra. Founded in 2003, by volunteer Pati Crofut, orchestra membership grew from eight to 22 female offenders between 2003 and 2009. Crofut has devoted her time…

  5. ANTHROPIC AND HABITATIONAL RESOURCES IN THE SOUTH-EASTERN PART OF THE TRASCĂU MOUNTAINS

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    Gabriela Adina LAZĂR

    2011-04-01

    Full Text Available The current paper represents an analysis and an overview of the anthropic component from the south-eastern part of the Trascău Mountains, its evolution as well as of the habitational resources (in terms of elements of the locative fund identified within the analyzed unit. The traditional values of these rural communities, the touristical potential and the uniqueness of the analyzed region recommend the implementation of adequate regional management measures in order to assert a sustainable development of the local communities strongly correlated with the biotic and abiotic component of the entire geocomplex of the Trascău Mountains.

  6. An integrated geophysical study of the southeastern Sangre de Cristo Mountains, New Mexico: Summary

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    Quezada, Oscar; Keller, G. Randy; Andronicos, Christopher

    The Sangre de Cristo Mountains in northern New Mexico are the uplifted eastern flank of the Rio Grande rift and expose a number of important geologic features whose origins are of great geologic interest (Figure 1). We have investigated this area, and here we present an integrated analysis of a variety of geophysical data that features almost 100 km of newly released seismic reflection data (Figure 1). The southeastern Sangre de Cristo Mountains are the site of a pronounced and yet poorly understood gravity minimum. By integrating different geophysical and geological data, we have focused on this gravity anomaly hoping that modeling the major upper crustal structures related to it aid in unraveling the complex tectonic evolution of the southern Rocky Mountains.

  7. Microstructural evidence for northeastward movement on the Chocolate Mountains fault zone, southeastern California

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    Simpson, C. (Johns Hopkins Univ., Baltimore, MD (United States))

    1990-01-10

    Microstructural analysis of rocks from the Chocolate Mountains fault zone, Gavilan Hills area, southeastern California, show unequivocal evidence for northeast directed transport of the upper plate gneisses over lower plate Orocopia schists. Samples were taken from transects through the fault zone. Prefaulting fabrics in upper plate gneisses show a strong component of northeast directed rotational deformation under lower amphibolite facies conditions. In contrast, prefaulting lower plate Orocopia schists show strongly coaxial fabrics (minimum stretch value of 2.2) formed at greenschist grade. Mylonitic fabrics associated with the Chocolate Mountains fault are predominantly northeast directed shear bands that are unidirectional (northeastward) in the gneisses but bi-directional in the schists, suggesting a significant component of nonrotational deformation occurred in the Orocopia schists during and after emplacement of the upper plate. The kinematic findings are in agreement with Dillon et al. (1989), who found that the vergence of asymmetrical folds within the fault zone indicates overthrusting to the northeast, toward the craton, in this region. The available evidence favors a single protracted northeastward movement on the Chocolate Mountains fault zone with temperatures waning as deformation proceeded.

  8. Paleoseismic investigations of Stagecoach Road fault, southeastern Yucca Mountain, Nye County, Nevada

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    Menges, C.M.; Oswald, J.A.; Coe, J.A.; Lundstrom, S.C.; Paces, J.B.; Mahan, S.A.; Widmann, B.; Murray, M.

    1998-04-01

    This report summarizes the results of paleoseismic investigations at two trenches (SCR-T1 and SCR-T3) excavated across the Stagecoach Road (SCR) fault at the southeastern margin of Yucca Mountain. The results of these studies are based on detailed mapping or logging of geologic and structural relationships exposed in trench walls, combined with descriptions of lithologic units, associated soils, and fault-related deformation. The ages of trench deposits are determined directly from geochronologic dating of selected units and soils, supplemented by stratigraphic and soil correlations with other surficial deposits in the Yucca Mountain area. The time boundaries used in this report for subdivision of the Quaternary period are listed in a table. These data and interpretations are used to identify the number, amounts, timing, and approximately lengths of late to middle Quaternary (less than 200 ka) surface-faulting events associated with paleoearthquakes at the trench sites. This displacement history forms the basis for calculating paleoearthquake recurrence intervals and fault-slip rates for the Stagecoach Road fault and allows comparison with fault behavior on other Quaternary faults at or near Yucca Mountain.

  9. Profiling Radar Observations and Numerical Simulations of a Downslope Wind Storm and Rotor on the Lee of the Medicine Bow Mountains in Wyoming

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    Binod Pokharel

    2017-02-01

    Full Text Available This study describes a downslope wind storm event observed over the Medicine Bow range (Wyoming, USA on 11 January 2013. The University of Wyoming King Air (UWKA made four along-wind passes over a five-hour period over the mountain of interest. These passes were recognized as among the most turbulent ones encountered in many years by crew members. The MacCready turbulence meter aboard the UWKA measured moderate to severe turbulence conditions on each pass in the lee of the mountain range, with eddy dissipation rate values over 0.5 m2/3 s−1. Three rawinsondes were released from an upstream location at different times. This event is simulated using the non-hydrostatic Weather Research and Forecast (WRF model at an inner- domain resolution of 1 km. The model produces a downslope wind storm, notwithstanding some discrepancies between model and rawinsonde data in terms of upstream atmospheric conditions. Airborne Wyoming Cloud Radar (WCR vertical-plane Doppler velocity data from two beams, one pointing to the nadir and one pointing slant forward, are synthesized to obtain a two-dimensional velocity field in the vertical plane below flight level. This synthesis reveals the fine-scale details of an orographic wave breaking event, including strong, persistent downslope acceleration, a strong leeside updraft (up to 10 m·s−1 flanked by counter-rotating vortices, and deep turbulence, extending well above flight level. The analysis of WCR-derived cross-mountain flow in 19 winter storms over the same mountain reveals that cross-mountain flow acceleration and downslope wind formation are difficult to predict from upstream wind and stability profiles.

  10. Structure and floristic similarities of upper montane forests in Serra Fina mountain range, southeastern Brazil

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    Leonardo Dias Meireles

    2015-03-01

    Full Text Available The upper montane forests in the southern and southeastern regions of Brazil have an unusual and discontinuous geographic distribution at the top of the Atlantic coastal mountain ranges. To describe the floristic composition and structure of the Atlantic Forest near its upper altitudinal limit in southeastern Brazil, 30 plots with 10 × 10 m were installed in three forest sites between 2,200 and 2,300 m.a.s.l. at Serra Fina. The floristic composition and phytosociological structure of this forest were compared with other montane and upper montane forests. In total, 704 individuals were included, belonging to 24 species, 15 families, and 19 genera. Myrsinaceae, Myrtaceae, Symplocaceae, and Cunoniaceae were the most important families, and Myrsine gardneriana, Myrceugenia alpigena, Weinmannia humilis, and Symplocos corymboclados were the most important species. The three forest sites revealed differences in the abundance of species, density, canopy height, and number of stems per individual. The upper montane forests showed structural similarities, such as lower richness, diversity, and effective number of species, and they tended to have higher total densities and total dominance per hectare to montane forests. The most important species in these upper montane forests belong to Austral-Antartic genera or neotropical and pantropical genera that are typical of montane areas. The high number of species shared by these forests suggests past connections between the vegetation in southern Brazilian high-altitude areas.

  11. Debris flows as geomorphic agents in the Huachuca Mountains of southeastern Arizona

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    Wohl, E.E.; Pearthree, P.P.

    1991-01-01

    Numerous debris flows occurred in the Huachuca Mountains of southeastern Arizona during the summer rainy season of 1988 in areas that were burned by a forest fire earlier in the summer. Debris flows occurred following a major forest fire in 1977 as well, suggesting a causal link between fires and debris flows. Abundant evidence of older debris flows preserved along channels and in mountain front fans indicates that debris flows have occurred repeteadly during the late Quaternary in this environment. Soil development in sequences of debris-flow deposits indicates that debris flows probably recur over time intervals of several hundred to a thousand years in individual drainage basins in the study area. Surface runoff in the steep drainage basins of the Huachuca Mountains is greatly enhanced following forest fires, as the hillslopes are denuded of their vegetative cover. Water and sediment eroded from the hillslope regolith are rapidly introduced into the upper reaches of tributary channels by widespread rilling and slope wash during rainfall events. This influx of water and sediment destabilizes regolith previously accumulated in the channel, triggering debris flows that scour the channel to bedrock in the upper reaches. Following a debris flow, the scoured, trapezoidally-shaped channel gradually assumes a swale shape and the percentage of exposed bedrock declines, as material is introduced from the slopes. Debris flows do a tremendous amount of work in a very short time, however, and are the major channel-forming events. Where the tributary channels enter larger, trunk channels, the debris flows serve as the main source of very coarse sediment. The local slope and coarse particle distribution of the trunk channel depend on the competence of water flows in the channel to transport the material introduced by debris flows. Where the smaller channels drain directly to the mountain front, debris flows create extensive alluvial fans which dominate the morphology of the

  12. Bats (Mammalia: Chiroptera of the southeastern Truong Son Mountains, Quang Ngai Province, Vietnam

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    Nguyen Truong Son

    2016-07-01

    Full Text Available Bat communities of mainland Southeast Asia can be highly diverse. Many are under threat. Despite this, regional faunal composition is not well documented for many areas, including regions of Vietnam.  We assessed the biodiversity of bats in a watershed protection forest in the southeastern Truong Son (Annamite Mountains, southwestern Quang Ngai Province, Vietnam in 2011–2013.  Twenty species of insectivorous bats were documented including a high diversity of Murina species Tube-nosed Bats.  Diversity and abundance indices were compared with that recorded previously in two nature reserves and one national park in Vietnam, and were higher or comparable in several measures despite the lack of a karst substrate for roosts.  Reproduction in the insectivorous bat fauna coincided with the early rainy season.  In the late dry season, pregnant females of several species were observed but volant juveniles were not present, whereas in the early wet season adult females were lactating or post-lactating and volant juveniles of nine species were detected.  We recorded echolocation calls of 14 bat species; for each species, we compared features of calls with those reported previously in other Asian localities.  For some species we found discrepancies in call metrics among studies, perhaps suggesting a greater hidden biodiversity of bats in Southeast Asia.

  13. Altitudinal distribution of birds in a mountainous region in southeastern Brazil

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    Francisco Mallet-Rodrigues

    2010-08-01

    Full Text Available We studied the altitudinal distribution of 426 bird species in the Serra dos Órgãos, a mountainous region in southeastern Brazil. Thirty-four localities were visited between 1991 and 2009. Our study revealed a decline in bird species richness with elevation, although a smaller number of species was recorded at lower altitudes (below 300 m possibly due to local extinctions caused by the intense human occupation of the region. A less diverse avifauna was found above 2,000 m, with only one species (Caprimulgus longirostris recorded exclusively in this altitudinal range. Most endemic species were found between 300 and 1,200 m, but the endemism was more significant at higher altitudes. Nearly half of the birds found above 1,400 m were endemic species. Most of the threatened species from the state of Rio de Janeiro recorded in our study were found below 1,200 m, but no significant difference was found between the proportions of threatened species among different altitudinal ranges. Species of seventeen genera have exhibited some replacement (sometimes with partial overlap along altitudinal gradients.

  14. Application of multi-temporal landform analysis in landslide susceptibility assessment for mountainous highway - a case study in southeastern Taiwan

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    Liu-Xuan, Jian; Wei-Kai, Huang; Po-Shen, Lin

    2016-04-01

    This study divided a coastal mountainous highway into small sections with slope unit, plot the multi-temporal landslide inventories, and analyze the relationships between the revegetation areas of the existing landslide and newly activated landslide to calculate landslide status Index (LSI). The RI represents the multi-temporal status of landslide status in each slope unit; three statuses and their representing colors were defined in this study. Red representing slope unit with continuously landslides, yellow for those with previous landslide but stable and revegetating, green are those without landslides. The regression lines became one of the parameters in establishing landslide status map. The study area, 407K to 439K of Provincial Highway No. 9, located in southeastern Taiwan and is the most important transport corridor connecting southern Taiwan and the east coast. In 2009 this mountainous highway was hit by Typhoon Morakot and several landslides, debris slides were triggered in the study area. The debris blocked the traffic and residential communities alone the highway became isolated. To this date some section of the highway still suffer from landslide hazard and transportation had to be temporarily interrupted during some occasions. The landslide status map of this transport corridor was established combining the result of field investigation, remote sensing interpretation, and the regression lines of LSI. The preliminary result shows that out of the 258 slope units, 13 (5%) showing continuous landslides, 44 (17%) became stable and revegetating. The result of this study could provide better information for mountainous highway safety management.

  15. Mitochondrial diversity in mountain horse population from the South-Eastern Europe.

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    Hristov, Peter; Yordanov, Georgi; Ivanova, Adriana; Mitkov, Ivan; Sirakova, Daniela; Mehandzyiski, Ivan; Radoslavov, Georgi

    2016-06-01

    It is believed that population structure of mountain horse breeds is preserved from any genetic introgression, because of their geographical isolation and specific semi-wild life style of husbandry. Till date there are no molecular data for the Balkan horses. In this study we try to give information about some autochthonous mountain horse breeds from Bulgaria. A total of 121 horses from three different mountain massifs are presented: Stara Planina (the Balkan mountain), the Rhodopes and Rila-Pirin massif were genotyped according to mitochondrial D-loop region. The results showed huge diversity of all known haplogroups with exception of C, F and R. West Eurasian haplogroups B, D, M and L were with the highest frequencies. Haplogroups A, J, I, O'P and Q were also observed with the highest frequencies, but not equally distributed among the three populations. Analyses of the horse breeds reveal preserved genetic profile of the Balkan and the Rhodopes mountains populations. In contrast, a Rila-Pirin breed unexpectedly showed mixed profile - a massive genetic introgression with an Asiatic-type haplogroups. A similar mixed Euro-Asiatic haplotype profile possessed the Carpathian mountain pony, although both populations are separated geographically and historically. The genetic pool of three Bulgarian mountain horse populations is highly heterogenic and because of that these breeds should be preserved.

  16. Field-trip guide to the southeastern foothills of the Santa Cruz Mountains in Santa Clara County, California

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    Stoffer, Philip W.; Messina, Paula

    2002-01-01

    This field trip is an introduction to the geology of the southeastern foothills of the Santa Cruz Mountains in southern Santa Clara County. Seven stops include four short hikes to access rock exposures and views of the foothills east of Loma Prieta Peak between Gilroy and San José. Field-trip destinations highlight the dominant rock types of the "Franciscan assemblage" including outcrops of serpentinite, basalt, limestone, ribbon chert, graywacke sandstone, and shale. General discussions include how the rocks formed, and how tectonism and stream erosion have changed the landscape through time. All field trip stops are on public land; most are near reservoir dams of the Santa Clara Valley Water District. In addition, stops include examination of an Ohlone Indian heritage site and the New Almaden Mining Museum.

  17. The Asian war bow

    CERN Document Server

    Nieminen, Timo A

    2011-01-01

    The bow is one of the earliest complex machines, a prime example of the storage and transfer of energy. The physics of the bow illuminates compromises and design choices made in Asian military archery.

  18. Ship bow waves

    Institute of Scientific and Technical Information of China (English)

    NOBLESSE Francis; DELHOMMEAU Gerard; LIU Hua; WAN De-cheng; YANG Chi

    2013-01-01

    The bow wave generated by a ship hull that advances at constant speed in calm water is considered.The bow wave only depends on the shape of the ship bow (not on the hull geometry aft of the bow wave).This basic property makes it possible to determine the bow waves generated by a canonical family of ship bows defined in terms of relatively few parameters.Fast ships with fine bows generate overturning bow waves that consist of detached thin sheets of water,which are mostly steady until they hit the main free surface and undergo turbulent breaking up and diffusion.However,slow ships with blunt bows create highly unsteady and turbulent breaking bow waves.These two alternative flow regimes are due to a nonlinear constraint related to the Bernoulli relation at the free surface.Recent results about the overturning and breaking bow wave regimes,and the boundary that divides these two basic flow regimes,are reviewed.Questions and conjectures about the energy of breaking ship bow waves,and free-surface effects on flow circulation,are also noted.

  19. THE DRAINAGE EFFICIENCY INDEX (DEI) AS AN MORPHOLOGIAL INDICATOR OF LANDSLIDE SPATIAL OCCURRENCE IN MOUNTAINOUS CATCHMENTS. A case of study applied in the mountainous region of Brazilian Southeastern.

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    Henrique Muniz Lima, Pedro; Luiza Coelho Netto, Ana; do Couto Fernandes, Manoel

    2016-04-01

    Morphometric parameters, acquired notoriety mainly after the Drainage Density proposition (Horton 1932, 1945) and after they were applied by geomorphologists on the perspective to understand landscape functionalities, quantifying their characteristics through parameters and indexes. After the drainage density, many other parameters which describe the basin characteristics, behavior and dynamics have been proposed. Among them, for example, the DEI was proposed by Coelho Netto and contributors during the 80's, while they were seek to understand the hydrological and erosive dynamics on Bananal river basin (Brazilian Southeastern). Through this investigations the DEI was created, revealing the importance of parameters as hollow and drainage density, conjugated to the topographic gradient (Meis et al. 1982) who prosecute controls on the water flow efficiency along the hollows in order to activate the regressive erosion of the main channel. Later on this index was applied on the basin scale in several works developed in mountainous regions, showing a remarkable correlation with the occurrence of landslides such as showed by Coelho Netto et al. (2007); that posteriorly use this index as one of the components of the landslide susceptibility map for the Tijuca Massif, located in Rio de Janeiro Municipality. This work aims to establish patterns of the DEI index values (applied to mountainous low order basins) and the relationship on the occurrence of Debriflows or shallow translational slides. For this, the DEI index was applied on 4 different study areas located on the Southeastern mountainous region of Brazil to address deeply the connection between the index and the occurrence of landslides of different types applied for first and second order basins. The major study area is the Córrego Dantas Basin, situated in Nova Friburgo municipality (RJ), which is a 53 km² basin was affected by 327 landslides caused by a heavy rainfall on January 2011; Coelho Netto et al. (in

  20. Stratigraphic framework of upper Paleozoic rocks, southeastern Sangre de Cristo Mountains, New Mexico

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    Baltz, E.H.; Myers, D.A.

    1999-01-01

    The Sangre de Cristo Mountains of south-central Colorado and north-central New Mexico are the physiographic expression of a southerly trending Cenozoic structural uplift that plunges gently south to die out in the Great Plains south of Santa Fe and Las Vegas, New Mexico. The uplift is bounded on the west by Neogene downfaulted and downwarped basins of the Rio Grande depression and, on the east, by broad Laramide basins that have sharply folded western limbs. The uplift was modified in Neogene time by local igneous-intrusive doming and normal faulting related to the Rio Grande rift.

  1. In situ cosmogenic 10Be dating of the Quaternary glaciations in the southern Shaluli Mountain on the Southeastern Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    WANG; Jian; Raisbeck; Grand; XU; Xiaobin; Yiou; Francios; BAI; Shibiao

    2006-01-01

    It is generally considered that four-times ice age happened during the Quaternary epoch on the Tibetan Plateau.However,the research on the chronology of the four-times ice age is far from enough.The Shaluli Mountain on the Southeastern Tibetan Plateau is an ideal place for plaeo-glacier study,because there are abundant Quaternary glacial remains there.This paper discusses the ages of the Quaternary glaciations,based on the exposure dating of roche moutonnée,moraines and glacial erosion surfaces using in situ cosmogenic isotopes 10Be.It is found that the exposure age of the roche moutonnée at Tuershan is 15 ka,corresponding to Stage 2 of the deep-sea oxygen isotope,suggesting that the roche moutonnée at Tuershan is formed in the last glacial maximum.The exposure age of glacial erosion surface at Laolinkou is 130-160 ka,corresponding to Stage 6 of the deep-sea oxygen isotope.The oldest end moraine at Kuzhaori may form at 421-766 kaBP,corresponding to Stages 12-18 of the deep-sea oxygen isotope.In accordance with the climate characteristic of stages 12,14,16 and 18 reflected by the deep-sea oxygen isotope,polar ice cores and loess sequence,the oldest end moraine at Kuzhaori may form at stage 12 or stage 16,the latter is more possible.

  2. An integrated geophysical study of the southeastern Sangre de Cristo Mountains, New Mexico: Summary

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    Cline, Veronica J.; Keller, G. Randy

    Southwestern Wyoming is located at the margin of the Archean Wyoming craton but has experienced significant deformation as a result of both the Sevier and Laramide orogenies. This study focuses on the nature and extent of this deformation and its interactions with structures within the Precambrian basement. We used about 350 km of newly released industry seismic reflection data along with gravity data, satellite imagery, and drilling information in an integrated analysis focusing on the north-south trending Rock Springs uplift, the northwest-trending Wind River uplift and the west-east trending Sweetwater uplift. These features form arches that are bounded by the Green River, Wind River, Great Divide, and the Washakie basins (Fig. 1). An example of the seismic data is shown in Figure 2 displays structural complexity at the northeast boundary of the Great Divide basin involving high-angle reverse faults with northeast dips. The fault that lies roughly in the middle of the line is interpreted to be the southeastern extension of the Wind River thrust, and the fault at the northeast end of the line is interpreted to be the Mormon Trail thrust. A gravity profile was modeled as a medium to integrate all of the data. This model of the upper crust indicates the presence of inhomogeneities in the Archean basement that have not been recognized previously. The basement northeast of the Wind River thrust contains considerable reflectivity indicating folding or fabric that either reflects or controls Laramide structures. The interweaving of reflectors in one line resemble imbricate structures shown in the CD-ROM Cheyenne belt deep reflection profile and could be related to an ancient structural boundary within the basement. Our analysis shows that the multiple thrusts bounding the Sweetwater uplift occur near major inhomogeneities in the Precambrian basement. Spatial relations we observe are consistent with the hypothesis that anastomosing arches characterize Laramide foreland

  3. Chloroplast pigments in post-fire-grown cryptophytes on Vidlič mountain (southeastern Serbia

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    Marković Marija S.

    2012-01-01

    Full Text Available In this study the content of chloroplast pigments (chlorophyll a, b, a+b, and carotenoids in the leaves of Geranium macrorrhizum L., Doronicum columnae Ten., Aegopodium podagraria L. and Tussilago farfara L. from a beech forest that had undergone fire on Vidlič Mountain was determined. The same species of plants from a place that had not been exposed to fire were taken as controls. Chloroplast pigments were determined from acetone extracts of these plants spectrophotometrically. In the first year after the fire the content of chlorophyll a, b and a+b in Geranium macrorrhizum L. and Doronicum columnae Ten. was greater than in the plants not exposed to fire. The results were the opposite for Aegopodium podagraria L. and Tussilago farfara L. These differences can be attributed to the different physiology of the plants and consequently their different adaptation patterns. The carotenoid content was higher in the plant species at the fire site than in the area not exposed to fire.

  4. Moisture source in the Hyblean Mountains region (south-eastern Sicily, Italy): Evidence from stable isotopes signature

    Energy Technology Data Exchange (ETDEWEB)

    Grassa, Fausto [Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Via Ugo La Malfa, 153, 90146 Palermo (Italy)]. E-mail: f.grassa@pa.ingv.it; Favara, Rocco [Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Via Ugo La Malfa, 153, 90146 Palermo (Italy); Valenza, Mariano [Dipartimento CFTA, Universita di Palermo, Palermo, Via Archirafi, 36, 90123, Palermo (Italy)

    2006-12-15

    Here the authors present results of an isotope study on precipitation collected during a 2-a period from a rain-gauge network consisting of 6 stations located at different elevations in the Hyblean Mountains (HM) region, in south-eastern Sicily. The slope of the local meteoric water line ({delta}D = 6.50 {delta} {sup 18}O + 9.87) obtained for the region suggests that precipitation is affected by evaporation during rainfall events. The main variations in rainwater isotope composition are due to seasonal effects and elevation. An average {sup 2}H excess value of +21.2 per mille was found for precipitation events less affected by evaporation (i.e. when the rainfall was >65 mm/month). The spatial distribution of O isotope composition of precipitation shows a negative gradient from east and south to the inner areas. The depositional rate of Cl, used as a tracer of the origin of air masses, is highest at the coastal rain-gauges (SR and MRG stations) and lowest on the northern flank of the HM region (SC station). Based on these findings, a model is proposed for the origin of precipitation in the HM region, which assumes that a Mediterranean-derived component is the main source of moisture in the studied area. D/H and {sup 18}O/{sup 16}O ratios of inferred meteoric recharge waters were also compared with the isotope composition of waters collected from the main local springs and wells. The best linear fit of the {delta} {sup 18}O vs {delta}D relationship for Hyblean groundwater is {delta}D = 4.85 {delta} {sup 18}O-2.01. The enrichment of heavy isotopes in Hyblean groundwater is probably due to evaporation occurring after precipitation events or to a recharging contribution from surface waters (lakes or rivers) enriched in heavy isotopes.

  5. Mountaineering

    Institute of Scientific and Technical Information of China (English)

    潘步东

    2005-01-01

    Most young people enjoy some forms of physical activities.It may be walking,cycling or swimming,or in wither,skating or skiing.It may be a game of some kind,football,hockey(曲棍球),golf,or tennis.Perhaps it may be mountaineering.

  6. Bow and catapult internal dynamics

    CERN Document Server

    Denny, M

    2003-01-01

    A simple model of bow and arrow dynamics is presented, which makes clear the physical principles, and reproduces the features obtained via more detailed, but less accessible calculations. We apply this instructive model to determine the efficiency of bows and of torsion-spring catapults.

  7. Bow and catapult internal dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Denny, Mark [4665 Amblewood Drive, Victoria, BC V8Y 1C1 (Canada)

    2003-07-01

    A simple model of bow and arrow dynamics is presented, which makes clear the physical principles, and reproduces the features obtained via more detailed, but less accessible calculations. We apply this instructive model to determine the efficiency of bows and of torsion-spring catapults.

  8. Mountain front migration and drainage captures related to fault segment linkage and growth: The Polopos transpressive fault zone (southeastern Betics, SE Spain)

    Science.gov (United States)

    Giaconia, Flavio; Booth-Rea, Guillermo; Martínez-Martínez, José Miguel; Azañón, José Miguel; Pérez-Romero, Joaquín; Villegas, Irene

    2013-01-01

    The Polopos E-W- to ESE-WNW-oriented dextral-reverse fault zone is formed by the North Alhamilla reverse fault and the North and South Gafarillos dextral faults. It is a conjugate fault system of the sinistral NNE-SSW Palomares fault zone, active from the late most Tortonian (≈7 Ma) up to the late Pleistocene (≥70 ky) in the southeastern Betics. The helicoidal geometry of the fault zone permits to shift SE-directed movement along the South Cabrera reverse fault to NW-directed shortening along the North Alhamilla reverse fault via vertical Gafarillos fault segments, in between. Since the Messinian, fault activity migrated southwards forming the South Gafarillos fault and displacing the active fault-related mountain-front from the north to the south of Sierra de Polopos; whilst recent activity of the North Alhamilla reverse fault migrated westwards. The Polopos fault zone determined the differential uplift between the Sierra Alhamilla and the Tabernas-Sorbas basin promoting the middle Pleistocene capture that occurred in the southern margin of the Sorbas basin. Continued tectonic uplift of the Sierra Alhamilla-Polopos and Cabrera anticlinoria and local subsidence associated to the Palomares fault zone in the Vera basin promoted the headward erosion of the Aguas river drainage that captured the Sorbas basin during the late Pleistocene.

  9. Bow shock data analysis

    Science.gov (United States)

    Zipf, Edward C.; Erdman, Peeter W.

    1994-08-01

    The University of Pittsburgh Space Physics Group in collaboration with the Army Research Office (ARO) modeling team has completed a systematic organization of the shock and plume spectral data and the electron temperature and density measurements obtained during the BowShock I and II rocket flights which have been submitted to the AEDC Data Center, has verified the presence of CO Cameron band emission during the Antares engine burn and for an extended period of time in the post-burn plume, and have adapted 3-D radiation entrapment codes developed by the University of Pittsburgh to study aurora and other atmospheric phenomena that involve significant spatial effects to investigate the vacuum ultraviolet (VUV) and extreme ultraviolet (EUV) envelope surrounding the re-entry that create an extensive plasma cloud by photoionization.

  10. Measurement of ambient aerosol hydration state at Great Smoky Mountains National Park in the southeastern United States

    Directory of Open Access Journals (Sweden)

    N. F. Taylor

    2011-12-01

    Full Text Available We present results from two field deployments of a unique tandem differential mobility analyzer (TDMA configuration with two primary capabilities: identifying alternative stable or meta-stable ambient aerosol hydration states associated with hysteresis in aerosol hydration behavior and determining the actual Ambient hydration State (AS-TDMA. This data set is the first to fully classify the ambient hydration state of aerosols despite recognition that hydration state significantly impacts the roles of aerosols in climate, visibility and heterogeneous chemistry. The AS-TDMA was installed at a site in eastern Tennessee on the border of Great Smoky Mountains National Park for projects during the summer of 2006 and winter of 2007–2008. During the summer, 12% of the aerosols sampled in continuous AS-TDMA measurements were found to posses two possible hydration states under ambient conditions. In every case, the more hydrated of the possible states was occupied. The remaining 88% did not posses multiple possible states. In continuous measurements during the winter, 49% of the aerosols sampled possessed two possible ambient hydration states; the remainder possessed only one. Of those aerosols with multiple possible ambient hydration states, 65% occupied the more hydrated state; 35% occupied the less hydrated state. This seasonal contrast is supported by differences in the fine particulate (PM2.5 composition and ambient RH as measured during the two study periods. In addition to seasonal summaries, this work includes case studies depicting the variation of hydration state with changing atmospheric conditions.

  11. Post-glacial landscape response to climate variability in the southeastern San Juan Mountains of Colorado, USA

    Science.gov (United States)

    Johnson, Bradley G.; Eppes, Martha Cary; Diemer, John A.; Jiménez-Moreno, Gonzalo; Layzell, Anthony L.

    2011-11-01

    Geomorphic mapping in the upper Conejos River Valley of the San Juan Mountains has shown that three distinct periods of aggradation have occurred since the end of the last glacial maximum (LGM). The first occurred during the Pleistocene-Holocene transition (~ 12.5-9.5 ka) and is interpreted as paraglacial landscape response to deglaciation after the LGM. Evidence of the second period of aggradation is limited but indicates a small pulse of sedimentation at ~ 5.5 ka. A third, more broadly identifiable period of sedimentation occurred in the late Holocene (~ 2.2-1 ka). The latest two periods of aggradation are concurrent with increases in the frequency of climate change in the region suggesting that Holocene alpine and sub-alpine landscapes respond more to rapid changes in climate than to large singular climatic swings. Soil development and radiocarbon dating indicate that hillslopes were stable during the Holocene even while aggradation was occurring in valley bottoms. Thus, we can conclude that erosion does not occur equally throughout the landscape but is focused upslope of headwater streams, along tributary channels, or on ridge tops. This is in contrast to some models which assume equal erosion in headwater basins.

  12. The Early Jurassic Bokan Mountain peralkaline granitic complex (southeastern Alaska): Geochemistry, petrogenesis and rare-metal mineralization

    Science.gov (United States)

    Dostal, Jaroslav; Kontak, Daniel J.; Karl, Susan M.

    2014-08-01

    The Early Jurassic (ca. 177 Ma) Bokan Mountain granitic complex, located on southern Prince of Wales Island, southernmost Alaska, cross-cuts Paleozoic igneous and metasedimentary rocks of the Alexander terrane of the North American Cordillera and was emplaced during a rifting event. The complex is a circular body (~ 3 km in diameter) of peralkaline granitic composition that has a core of arfvedsonite granite surrounded by aegirine granite. All the rock-forming minerals typically record a two-stage growth history and aegirine and arfvedsonite were the last major phases to crystallize from the magma. The Bokan granites and related dikes have SiO2 from 72 to 78 wt.%, high iron (FeO (tot) ~ 3-4.5 wt.%) and alkali (8-10 wt.%) concentrations with high FeO(tot)/(FeO(tot) + MgO) ratios (typically > 0.95) and the molar Al2O3/(Na2O + K2O) ratio metal (REE, Y, U, Th, Nb) mineralization that is related to the late-stage crystallization history of the complex which involved the overlap of emplacement of felsic dikes, including pegmatite bodies, and generation of orthomagmatic fluids. The abundances of REE, HFSE, U and Th as well as Pb and Nd isotopic values of the pluton and dikes were modified by orthomagmatic hydrothermal fluids highly enriched in the strongly incompatible trace elements, which also escaped along zones of structural weakness to generate rare-metal mineralization. The latter was deposited in two stages: the first relates to the latest stage of magma emplacement and is associated with felsic dikes that intruded along the faults and shear deformations, whereas the second stage involved ingress of hydrothermal fluids that both remobilized and enriched the initial magmatic mineralization. Mineralization is mostly composed of “new” minerals. Fluorine complexing played a role during the transportation of REE and HFSE in hydrothermal fluids and oxygen isotopes in the granites and quartz veins negate the significant incursion of an external fluid and support a

  13. The Early Jurassic Bokan Mountain peralkaline granitic complex (southeastern Alaska): geochemistry, petrogenesis and rare-metal mineralization

    Science.gov (United States)

    Dostal, Jaroslav; Kontak, Daniel J.; Karl, Susan M.

    2014-01-01

    The Early Jurassic (ca. 177 Ma) Bokan Mountain granitic complex, located on southern Prince of Wales Island, southernmost Alaska, cross-cuts Paleozoic igneous and metasedimentary rocks of the Alexander terrane of the North American Cordillera and was emplaced during a rifting event. The complex is a circular body (~3 km in diameter) of peralkaline granitic composition that has a core of arfvedsonite granite surrounded by aegirine granite. All the rock-forming minerals typically record a two-stage growth history and aegirine and arfvedsonite were the last major phases to crystalize from the magma. The Bokan granites and related dikes have SiO2 from 72 to 78 wt. %, high iron (FeO (tot) ~3-4.5 wt. %) and alkali (8-10 wt.%) concentrations with high FeO(tot)/(FeO(tot)+MgO) ratios (typically >0.95) and the molar Al2O3/(Na2O+K2O) ratio Nd values which are indicative of a mantle signature. The parent magma is inferred to be derived from an earlier metasomatized lithospheric mantle by low degrees of partial melting and generated the Bokan granitic melt through extensive fractional crystallization. The Bokan complex hosts significant rare-metal (REE, Y, U, Th, Nb) mineralization that is related to the late-stage crystallization history of the complex which involved the overlap of emplacement of felsic dikes, including pegmatite bodies, and generation of orthomagmatic fluids. The abundances of REE, HFSE, U and Th as well as Pb and Nd isotopic values of the pluton and dikes were modified by orthomagmatic hydrothermal fluids highly enriched in the strongly incompatible trace elements, which also escaped along zones of structural weakness to generate rare-metal mineralization. The latter was deposited in two stages: the first relates to the latest stage of magma emplacement and is associated with felsic dikes that intruded along the faults and shear deformations, whereas the second stage involved ingress of hydrothermal fluids that both remobilized and enriched the initial

  14. Some aspects of vocal fold bowing.

    Science.gov (United States)

    Tanaka, S; Hirano, M; Chijiwa, K

    1994-05-01

    Bowing of the vocal fold frequently occurs in patients with vocal fold paralysis (VFP), those with sulcus vocalis, and those who have had laser surgery. Additionally, there are vocal folds that present bowing with no noticeable organic lesion. For the purpose of investigating the causes and mechanisms of vocal fold bowing, consecutive fiberscopic videorecordings of 127 patients with VFP, 33 with sulcus vocalis, 33 with laser surgery, and 33 with dysphonia having no clinically noticeable organic lesion were reviewed. Sixty-nine percent of the paralyzed vocal folds had bowing, and the occurrence of bowing was significantly related to the activity of the thyroarytenoid muscle as measured by electromyography. The cricothyroid activity had no significant relationship to vocal fold bowing. All vocal folds with sulcus presented with bowing. Thirty-five percent of the vocal folds that had had laser surgery had bowing. The extent of tissue removal was closely related to the occurrence of bowing. Twelve cases with no organic lesion had vocal fold bowing. Of these 12 patients, 8 were male and 9 were older than 60 years. Some aging process in the mucosa was presumed to be the cause of the bowing in this age group of patients without clinically noticeable organic lesions. Causes of vocal fold bowing in the younger group of patients without organic lesions were not determined in this study.

  15. The Frequency of Growing Season Frost in the Subalpine Environment (Medicine Bow Mountains, Southeastern Wyoming), The Interaction of Leaf Morphology and Infrared Radiational Cooling and the Effects of Freezing on Native Vegetation

    Science.gov (United States)

    1995-05-01

    indicated in Fig. 2.3. Sky IR = -1.02 * sky% + 366 (r2 = 0.98) 30 Figure 2.5 A: Changes in leaf width (•) in Taraxacum officinale across a gradient...from this phase of the analysis. Leaf width (measured at the leaf midpoint) and DP AR were measured for Taraxacum officinale Webb at ten sites along...A: Changes in leaf width (•) in Taraxacum officinale across a gradient in elevation and sky IR. B: Changes in leaf width (•) and leaf length (O) of

  16. Dielectric Bow-tie Nanocavity

    CERN Document Server

    Lu, Qijing; Zou, Chang-Ling

    2013-01-01

    We propose a novel dielectric bow-tie nanocavity consisting of two tip-to-tip opposite triangle semiconductor nanowires, whose end faces are coated by silver nanofilms. Based on the advantages of the dielectric slot and tip structures, and the high reflectivity from the silver mirror, light can be confined in this nanocavity with low loss. We demonstrate that the mode excited in this nanocavity has a deep subwavelength mode volume of 2.8*10^-4 um3 and a high quality factor of 4.9*10^4 (401.3), consequently an ultrahigh Purcell factor of 1.6*10^7 (1.36*10^5), at 4.5 K (300 K) around the resonance wavelength of 1550 nm. This dielectric bow-tie nanocavity may find applications for integrated nanophotonic circuits, such as high-efficiency single photon source, thresholdless nanolaser, and cavity QED strong coupling experiments.

  17. Entropy Generation Across Earth's Bow Shock

    Science.gov (United States)

    Parks, George K.; McCarthy, Michael; Fu, Suiyan; Lee E. s; Cao, Jinbin; Goldstein, Melvyn L.; Canu, Patrick; Dandouras, Iannis S.; Reme, Henri; Fazakerley, Andrew; Lin, Naiguo; Wilber, Mark

    2011-01-01

    Earth's bow shock is a transition layer that causes an irreversible change in the state of plasma that is stationary in time. Theories predict entropy increases across the bow shock but entropy has never been directly measured. Cluster and Double Star plasma experiments measure 3D plasma distributions upstream and downstream of the bow shock that allow calculation of Boltzmann's entropy function H and his famous H-theorem, dH/dt O. We present the first direct measurements of entropy density changes across Earth's bow shock. We will show that this entropy generation may be part of the processes that produce the non-thermal plasma distributions is consistent with a kinetic entropy flux model derived from the collisionless Boltzmann equation, giving strong support that solar wind's total entropy across the bow shock remains unchanged. As far as we know, our results are not explained by any existing shock models and should be of interests to theorists.

  18. Blood parasites, total plasma protein and packed cell volume of small wild mammals trapped in three mountain ranges of the Atlantic Forest in Southeastern Brazil.

    Science.gov (United States)

    Silva, M A M L; Ronconi, A; Cordeiro, N; Bossi, D E P; Bergallo, H G; Costa, M C C; Balieiro, J C C; Varzim, F L S B

    2007-08-01

    A study of blood parasites in small wild non-flying mammals was undertaken in three areas of the Atlantic Forest in Southeastern Brazil: Serra de Itatiaia, RJ, Serra da Bocaina, SP and Serra da Fartura, SP, from June 1999 to May 2001. A total of 450 animals (15 species) were captured in traps and it was observed in 15.5% of the blood smears the presence of Haemobartonella sp. and Babesia sp. in red blood cells. There was no statistically significant difference between parasited and non-parasited specimens regarding total plasma protein, packed cell volume and body weight, which strongly suggests that these specimens might be parasite reservoirs.

  19. Regeneration after 8 years in artificial canopy gaps in mountain ash (Eucalyptus regnans F. Muell.) forest in south-eastern Australia

    NARCIS (Netherlands)

    Meer, van der P.J.; Dignan, P.

    2007-01-01

    We report on a study of regeneration of Mountain Ash (Eucalyptus regnans) forest in S.E. Australia in artificially created canopy gaps (0.01¿2 ha) and clearfelled coupes (4¿27 ha) with different seedbed treatments. Treatments were applied in 1988, 1989, and 1990. Our results are based on measurement

  20. Ground-Dwelling Arthropod Communities of a Sky Island Mountain Range in Southeastern Arizona, USA: Obtaining a Baseline for Assessing the Effects of Climate Change.

    Directory of Open Access Journals (Sweden)

    Wallace M Meyer

    Full Text Available The few studies that have addressed past effects of climate change on species distributions have mostly focused on plants due to the rarity of historical faunal baselines. However, hyperdiverse groups like Arthropoda are vital to monitor in order to understand climate change impacts on biodiversity. This is the first investigation of ground-dwelling arthropod (GDA assemblages along the full elevation gradient of a mountain range in the Madrean Sky Island Region, establishing a baseline for monitoring future changes in GDA biodiversity. To determine how GDA assemblages relate to elevation, season, abiotic variables, and corresponding biomes, GDA were collected for two weeks in both spring (May and summer (September 2011 in the Santa Catalina Mountains, Arizona, using pitfall traps at 66 sites in six distinct upland (non-riparian/non-wet canyon biomes. Four arthropod taxa: (1 beetles (Coleoptera, (2 spiders (Araneae, (3 grasshoppers and crickets (Orthoptera, and (4 millipedes and centipedes (Myriapoda were assessed together and separately to determine if there are similar patterns across taxonomic groups. We collected 335 species of GDA: 192/3793 (species/specimens Coleoptera, 102/1329 Araneae, 25/523 Orthoptera, and 16/697 Myriapoda. GDA assemblages differed among all biomes and between seasons. Fifty-three percent (178 species and 76% (254 species of all GDA species were found in only one biome and during only one season, respectively. While composition of arthropod assemblages is tied to biome and season, individual groups do not show fully concordant patterns. Seventeen percent of the GDA species occurred only in the two highest-elevation biomes (Pine and Mixed Conifer Forests. Because these high elevation biomes are most threatened by climate change and they harbor a large percentage of unique arthropod species (11-25% depending on taxon, significant loss in arthropod diversity is likely in the Santa Catalina Mountains and other isolated

  1. Ground-Dwelling Arthropod Communities of a Sky Island Mountain Range in Southeastern Arizona, USA: Obtaining a Baseline for Assessing the Effects of Climate Change.

    Science.gov (United States)

    Meyer, Wallace M; Eble, Jeffrey A; Franklin, Kimberly; McManus, Reilly B; Brantley, Sandra L; Henkel, Jeff; Marek, Paul E; Hall, W Eugene; Olson, Carl A; McInroy, Ryan; Bernal Loaiza, Emmanuel M; Brusca, Richard C; Moore, Wendy

    2015-01-01

    The few studies that have addressed past effects of climate change on species distributions have mostly focused on plants due to the rarity of historical faunal baselines. However, hyperdiverse groups like Arthropoda are vital to monitor in order to understand climate change impacts on biodiversity. This is the first investigation of ground-dwelling arthropod (GDA) assemblages along the full elevation gradient of a mountain range in the Madrean Sky Island Region, establishing a baseline for monitoring future changes in GDA biodiversity. To determine how GDA assemblages relate to elevation, season, abiotic variables, and corresponding biomes, GDA were collected for two weeks in both spring (May) and summer (September) 2011 in the Santa Catalina Mountains, Arizona, using pitfall traps at 66 sites in six distinct upland (non-riparian/non-wet canyon) biomes. Four arthropod taxa: (1) beetles (Coleoptera), (2) spiders (Araneae), (3) grasshoppers and crickets (Orthoptera), and (4) millipedes and centipedes (Myriapoda) were assessed together and separately to determine if there are similar patterns across taxonomic groups. We collected 335 species of GDA: 192/3793 (species/specimens) Coleoptera, 102/1329 Araneae, 25/523 Orthoptera, and 16/697 Myriapoda. GDA assemblages differed among all biomes and between seasons. Fifty-three percent (178 species) and 76% (254 species) of all GDA species were found in only one biome and during only one season, respectively. While composition of arthropod assemblages is tied to biome and season, individual groups do not show fully concordant patterns. Seventeen percent of the GDA species occurred only in the two highest-elevation biomes (Pine and Mixed Conifer Forests). Because these high elevation biomes are most threatened by climate change and they harbor a large percentage of unique arthropod species (11-25% depending on taxon), significant loss in arthropod diversity is likely in the Santa Catalina Mountains and other isolated

  2. Blood parasites, total plasma protein and packed cell volume of small wild mammals trapped in three mountain ranges of the Atlantic Forest in Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    MAML. Silva

    Full Text Available A study of blood parasites in small wild non-flying mammals was undertaken in three areas of the Atlantic Forest in Southeastern Brazil: Serra de Itatiaia, RJ, Serra da Bocaina, SP and Serra da Fartura, SP, from June 1999 to May 2001. A total of 450 animals (15 species were captured in traps and it was observed in 15.5% of the blood smears the presence of Haemobartonella sp. and Babesia sp. in red blood cells. There was no statistically significant difference between parasited and non-parasited specimens regarding total plasma protein, packed cell volume and body weight, which strongly suggests that these specimens might be parasite reservoirs.

  3. Dielectric bow-tie nanocavity.

    Science.gov (United States)

    Lu, Qijing; Shu, Fang-Jie; Zou, Chang-Ling

    2013-12-15

    We propose a novel dielectric bow-tie (DBT) nanocavity consisting of two opposing tip-to-tip triangle semiconductor nanowires, whose end faces are coated by silver nanofilms. Based on the advantages of the dielectric slot and tip structures, and the high reflectivity of the silver mirror, light can be confined in this nanocavity with low loss. We demonstrate that at 4.5 K (300 K) around the resonance wavelength of 1550 nm, the mode excited in this nanocavity has a deep subwavelength mode volume of 2.8×10(-4) μm³ and a high quality factor of 4.9×10(4) (401.3), corresponding to an ultrahigh Purcell factor of 1.6×10(7) (1.36×10(5)). This DBT nanocavity may find applications for integrated nanophotonic circuits, such as high-efficiency single photon sources, thresholdless nanolasers, and strong coupling in cavity quantum electrodynamics experiments.

  4. Applied Geospatial Education: Acquisition and Processing of High Resolution Airborne LIDAR and Orthoimages for the Great Smoky Mountains National Park, Southeastern United States

    Science.gov (United States)

    Jordan, T. R.; Madden, M.; Sharma, J. B.; Panda, S. S.

    2012-07-01

    In an innovative collaboration between government, university and private industry, researchers at the University of Georgia and Gainesville State College are collaborating with Photo Science, Inc. to acquire, process and quality control check lidar and or-thoimages of forest areas in the Southern Appalachian Mountains of the United States. Funded by the U.S. Geological Survey, this project meets the objectives of the ARRA initiative by creating jobs, preserving jobs and training students for high skill positions in geospatial technology. Leaf-off lidar data were acquired at 1-m resolution of the Tennessee portion of the Great Smoky Mountain National Park (GRSM) and adjacent Foothills Parkway. This 1400-sq. km. area is of high priority for national/global interests due to biodiversity, rare and endangered species and protection of some of the last remaining virgin forest in the U.S. High spatial resolution (30 cm) leaf-off 4-band multispectral orthoimages also were acquired for both the Chattahoochee National Forest in north Georgia and the entire GRSM. The data are intended to augment the National Elevation Dataset and orthoimage database of The National Map with information that can be used by many researchers in applications of LiDAR point clouds, high resolution DEMs and or-thoimage mosaics. Graduate and undergraduate students were involved at every stage of the workflow in order to provide then with high level technical educational and professional experience in preparation for entering the geospatial workforce. This paper will present geospatial workflow strategies, multi-team coordination, distance-learning training and industry-academia partnership.

  5. Effect of Buffer Bow Structure in Ship-Ship Collision

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2008-01-01

    tankers, the introduction of buffer bulbous bows has been proposed. Relatively soft buffer bows absorb part of the kinetic energy of the striking ship before penetrating the inner hull of the struck vessel. The purpose of the present paper is to verify the effectiveness of a prototype buffer bulbous bow......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

  6. 鄂东南低山丘陵区五节芒防除试验%Experiment on Control of Miscanthus floridulus in the Low Mountains and Hilly Area in Southeastern Hubei

    Institute of Scientific and Technical Information of China (English)

    孙拥康; 汤景明; 冯祥成; 陈文武

    2015-01-01

    为筛选出防除五节芒效果较好的除草剂,利用农达(41%草甘膦)、百草枯、精喹禾灵三种除草剂,开展鄂东南低山丘陵区五节芒防除试验,结果表明:三种除草剂除草效果与施药剂量、施药时间呈正比时,三种除草剂均可有效控制五节芒生长;但综合施药和成本情况,确定出农达(41%草甘膦)为防治五节芒优选除草剂,施药剂量以3000 mL•hm-2为宜。%In order to select better herbicide for Control Miscanthus floridulus ,we carried out the experiments on controlling Miscanthus floridulus control experiments with roundu (41% glyphosate),paraquat and 10% quizalofop-p-ethyl in the low mountains and hilly area in southeastern Hubei.The results showed that the weed control effect of these three kinds of herbicide were proportional to their dose and spraying duration.Three kinds of herbicide could all control its growth.And the pesticide dose and the cost synthetically determined that roundu(41% glyphosate)and within the application dosage in 3 000 mL•hm-2 was the optimal selection.

  7. Bow-arrow interaction in archery.

    Science.gov (United States)

    Kooi, B W

    1998-11-01

    A mathematical model of the flight of the arrow during its discharge from a bow was proposed by Pekalski (1990). His description of the model was incomplete. In this paper, I give a full description of the model. Furthermore, I propose some improvements that make his model more consistent with reality. One achievement is the modelling of contact of the arrow and grip; the pressure button is modelled as a unilateral elastic support. The acceleration force acting upon the arrow during the launch is predicted by an advanced mathematical model of bow dynamics. There is a satisfactory conformity of the simulation and experimental results. The new model predicts that the arrow leaves the pressure button before it leaves the string, as reported previously. The ability to model arrow dynamics can be used to improve the adjustment of the bow-arrow system for optimal performance.

  8. 46 CFR 154.355 - Bow and stern loading piping.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Bow and stern loading piping. 154.355 Section 154.355... Arrangements § 154.355 Bow and stern loading piping. (a) Bow and stern loading piping must: (1) Meet § 154.310...; (3) Be clearly marked; (4) Be segregated from the cargo piping by a removable spool piece in...

  9. Assessment of potential migration of radionuclides and trace elements from the White Mesa uranium mill to the Ute Mountain Ute Reservation and surrounding areas, southeastern Utah

    Science.gov (United States)

    Naftz, David L.; Ranalli, Anthony J.; Rowland, Ryan C.; Marston, Thomas M.

    2011-01-01

    In 2007, the Ute Mountain Ute Tribe requested that the U.S. Environmental Protection Agency and U.S. Geological Survey conduct an independent evaluation of potential offsite migration of radionuclides and selected trace elements associated with the ore storage and milling process at an active uranium mill site near White Mesa, Utah. Specific objectives of this study were (1) to determine recharge sources and residence times of groundwater surrounding the mill site, (2) to determine the current concentrations of uranium and associated trace elements in groundwater surrounding the mill site, (3) to differentiate natural and anthropogenic contaminant sources to groundwater resources surrounding the mill site, (4) to assess the solubility and potential for offsite transport of uranium-bearing minerals in groundwater surrounding the mill site, and (5) to use stream sediment and plant material samples from areas surrounding the mill site to identify potential areas of offsite contamination and likely contaminant sources. The results of age-dating methods and an evaluation of groundwater recharge temperatures using dissolved-gas samples indicate that groundwater sampled in wells in the surficial aquifer in the vicinity of the mill is recharged locally by precipitation. Tritium/helium age dating methods found a "modern day" apparent age in water samples collected from springs in the study area surrounding the mill. This apparent age indicates localized recharge sources that potentially include artificial recharge of seepage from constructed wildlife refuge ponds near the mill. The stable oxygen isotope-ratio, delta oxygen-18, or δ(18O/16O), known as δ18O, and hydrogen isotope-ratio, delta deuterium, or δ(2H/1H), known as δD, data indicate that water discharging from Entrance Spring is isotopically enriched by evaporation and has a similar isotopic fingerprint as water from Recapture Reservoir, which is used as facilities water on the mill site. Water from Recapture

  10. Suprathermal electrons at Saturn's bow shock

    CERN Document Server

    Masters, A; Sergis, N; Stawarz, L; Fujimoto, M; Coates, A J; Dougherty, M K

    2016-01-01

    The leading explanation for the origin of galactic cosmic rays is particle acceleration at the shocks surrounding young supernova remnants (SNRs), although crucial aspects of the acceleration process are unclear. The similar collisionless plasma shocks frequently encountered by spacecraft in the solar wind are generally far weaker (lower Mach number) than these SNR shocks. However, the Cassini spacecraft has shown that the shock standing in the solar wind sunward of Saturn (Saturn's bow shock) can occasionally reach this high-Mach number astrophysical regime. In this regime Cassini has provided the first in situ evidence for electron acceleration under quasi-parallel upstream magnetic conditions. Here we present the full picture of suprathermal electrons at Saturn's bow shock revealed by Cassini. The downstream thermal electron distribution is resolved in all data taken by the low-energy electron detector (CAPS-ELS, 18 keV) measured a suprathermal electron signature at 31 of 508 crossings, where typically onl...

  11. Plastic bowing of the ribs in children

    Energy Technology Data Exchange (ETDEWEB)

    Caro, P.A.; Borden, S. IV

    1988-06-01

    Four cases of plastic bowing of the ribs are presented. In three patients with Werdnig-Hoffman disease, plastic curvatures were associated with chronic pneumonia and atelectasis. We postulate that intrapulmonary retractive forces can deform ribs thinned by muscular atrophy. In turn, thoracic collapse can perpetuate lobar and segmental atelectasis. In one case of osteogenesis imperfecta without pneumonia, we believe normal muscle forces bent ribs weakened by deficiency of normal cortical architecture.

  12. Energetics of nearby stellar bow shocks

    CERN Document Server

    Benaglia, Paula

    2012-01-01

    The latest survey of stellar bow shocks (Peri et al. 2012) lists 28 candidates detected at IR wavelengths, associated with massive, early-type stars up to 3 kpc, along with the geometrical parameters of the structures found. I present here some considerations on the energetics involved, after the estimation of stellar wind power, infrared flux, stellar bolometric luminosity and radio flux limits for each source. The best candidates for relativistic particle acceleration are highlighted.

  13. Rotationnal and translational waves in a bowed string

    CERN Document Server

    Bavu, E; Placais, P Y; Smith, J; Wolfe, J; Bavu, Eric; Yew, Manfred; Placais, Pierre-Yves; Smith, John; Wolfe, Joe

    2005-01-01

    We measure and compare the rotational and transverse velocity of a bowed string. When bowed by an experienced player, the torsional motion is phase-locked to the transverse waves, producing highly periodic motion. The spectrum of the torsional motion includes the fundamental and harmonics of the transverse wave, with strong formants at the natural frequencies of the torsional standing waves in the whole string. Volunteers with no experience on bowed string instruments, however, often produced non-periodic motion. We present sound files of both the transverse and torsional velocity signals of well-bowed strings. The torsional signal has not only the pitch of the transverse signal, but it sounds recognisably like a bowed string, probably because of its rich harmonic structure and the transients and amplitude envelope produced by bowing.

  14. The sacred weapon: bow and arrow combat in Iran

    Directory of Open Access Journals (Sweden)

    Manouchehr Moshtagh Khorasani

    2012-07-01

    Full Text Available The following article presents the development of the bow and arrow, and its important role in the history of Iran. The bow always played an important role not only on the battlefield, but also in hunting. It was also considered as a sacred weapon and additionally a royal symbol. Bow and arrow were considered as a superior weapon in comparison with other types of weapons because one could fight with them at a safer distance as one offered by swords, maces and axes. The first part of the article presents a short history of the bow in Iran. Based on historical Persian manuscripts, the next part explains the structure of the composite bow and the materials used for making it. The third part describes some types of bows based on the material, place of production, the usage, and bow type based on the length of the bow and the arrows. The following part talks about different types of arrows based on morphology of arrowheads, the type of plume/feather, the material of the shaft, the material of the arrowhead, the length of arrows, the target of arrows, the place of production of arrowheads and terms for describing its different features of an arrowhead. Then, the article talks about different types of thumb rings, bowstrings, quivers and bow cases and arrow guides for shooting short arrows. The next part discusses different principles of archery as explained in Persian manuscripts. Finally the article describes different archery targets.

  15. SHRIMP Geochronology of Volcanics of the Zhangjiakou and Yixian Formations, Northern Hebei Province, with a Discussion on the Age of the Xing'anling Group of the Great Hinggan Mountains and Volcanic Strata of the Southeastern Coastal Area of China

    Institute of Scientific and Technical Information of China (English)

    NIU Baogui; HE Zhengjun; SONG Biao; REN Jishun; XIAO Liwei

    2004-01-01

    A zircon U-Pb geochronological study on the volcanic rocks reveals that both of the Zhangjiakou and Yixian Formations, northern Hebei Province, are of the Early Cretaceous, with ages of 135-130 Ma and 129-120 Ma,respectively. It is pointed out that the ages of sedimentary basins and volcanism in the northern Hebei -western Liaoning area become younger from west to east, i. e. the volcanism of the Luanping Basin commenced at c. 135 Ma, the Luotuo Mount area of the Chengde Basin c. 130 Ma, and western Liaoning c. 128 Ma. With a correlation of geochronological stratigraphy and biostratigraphy, we deduce that the Xing'anling Group, which comprises the Great Hinggan Mountains volcanic rock belt in eastern China, is predominantly of the early-middle Early Cretaceous, while the Jiande and Shimaoshan Groups and their equivalents, which form the volcanic rock belt in the southeastern coast area of China, are of the mid-late Early Cretaceous, and both the Jehol and Jiande Biotas are of the Early Cretaceous, not Late Jurassic or Late Jurassic-Early Cretaceous. Combining the characteristics of the volcanic rocks and, in a large area, hiatus in the strata of the Late Jurassic or Late Jurassic-early Early Cretaceous between the formations mentioned above and the underlying sequences, we can make the conclusion that, in the Late Jurassic-early Early Cretaceous, the eastern China region was of high relief or plateau, where widespread post-orogenic volcanic series of the Early Cretaceous obviously became younger from inland in the west to continental margin in the east. This is not the result of an oceanward accretion of the subduction belt between the Paleo-Pacific ocean plate and the Asian continent, but rather reflects the extension feature, i.e. after the closure of the Paleo-Pacific ocean, the Paleo-Pacific ancient continent collided with the Asian continent and reached the peak of orogenesis, and then the compression waned and resulted in the retreating of the post

  16. 76 FR 13666 - Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering Group, Including On-Site...

    Science.gov (United States)

    2011-03-14

    ... Employment and Training Administration Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering... firm worker group should read: Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering... workers of Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering Group, including...

  17. Suprathermal Electrons at Saturn's Bow Shock

    Science.gov (United States)

    Masters, A.; Sulaiman, A. H.; Sergis, N.; Stawarz, L.; Fujimoto, M.; Coates, A. J.; Dougherty, M. K.

    2016-07-01

    The leading explanation for the origin of galactic cosmic rays is particle acceleration at the shocks surrounding young supernova remnants (SNRs), although crucial aspects of the acceleration process are unclear. The similar collisionless plasma shocks frequently encountered by spacecraft in the solar wind are generally far weaker (lower Mach number) than these SNR shocks. However, the Cassini spacecraft has shown that the shock standing in the solar wind sunward of Saturn (Saturn's bow shock) can occasionally reach this high-Mach number astrophysical regime. In this regime Cassini has provided the first in situ evidence for electron acceleration under quasi-parallel upstream magnetic conditions. Here we present the full picture of suprathermal electrons at Saturn's bow shock revealed by Cassini. The downstream thermal electron distribution is resolved in all data taken by the low-energy electron detector (CAPS-ELS, 18 keV) measured a suprathermal electron signature at 31 of 508 crossings, where typically only the lowest energy channels (process involves interaction with whistler waves at the shock front, and becomes possible for all upstream magnetic field orientations at high Mach numbers like those of the strong shocks around young SNRs. A future dedicated study will analyze the rare crossings with evidence for relativistic electrons (up to ˜1 MeV).

  18. Muscular activation patterns of the bow arm in recurve archery.

    Science.gov (United States)

    Ertan, Hayri

    2009-05-01

    In archery shooting, the archer should hold the bow in place using only the pressure produced through drawing back the bowstring. Most coaches discourage the archer from gripping the bow as this is believed to produce a sideways deflecting torque on the bow and arrow during the release. The purpose of this study was to compare the bow hand forearm muscular activation patterns of elite archers with beginners to define the muscular contraction-relaxation strategies in the bow hand forearm muscles during archery shooting and investigate the effects of performance level on these strategies. Electromyographic activity of the M. flexor digitorum superficialis and the M. extensor digitorum of 10 elite and 10 beginner archers were recorded together with a pulse synchronized with the clicker snap. Raw electromyographic records as 1s before and after the clicker pulse were rectified, integrated, and normalized. The data was then averaged for successive shots of each subject and later for both groups of archers. The main difference between the elite and beginner archers was that the elite archers had a greater activation of the M. extensor digitorum, which indicates that they avoid gripping the bow-handle not only relaxing the flexor muscles, but also contracting the extensor muscle groups. This muscular contraction strategy secures the archer to not interfere with the forward movement of the bow, which is the forward acceleration of the bow caused by the pushing power of the bowstring.

  19. Evolution of bow-tie architectures in biology.

    Directory of Open Access Journals (Sweden)

    Tamar Friedlander

    2015-03-01

    Full Text Available Bow-tie or hourglass structure is a common architectural feature found in many biological systems. A bow-tie in a multi-layered structure occurs when intermediate layers have much fewer components than the input and output layers. Examples include metabolism where a handful of building blocks mediate between multiple input nutrients and multiple output biomass components, and signaling networks where information from numerous receptor types passes through a small set of signaling pathways to regulate multiple output genes. Little is known, however, about how bow-tie architectures evolve. Here, we address the evolution of bow-tie architectures using simulations of multi-layered systems evolving to fulfill a given input-output goal. We find that bow-ties spontaneously evolve when the information in the evolutionary goal can be compressed. Mathematically speaking, bow-ties evolve when the rank of the input-output matrix describing the evolutionary goal is deficient. The maximal compression possible (the rank of the goal determines the size of the narrowest part of the network-that is the bow-tie. A further requirement is that a process is active to reduce the number of links in the network, such as product-rule mutations, otherwise a non-bow-tie solution is found in the evolutionary simulations. This offers a mechanism to understand a common architectural principle of biological systems, and a way to quantitate the effective rank of the goals under which they evolved.

  20. Marble bowing: comparative studies of three different public building facades

    Science.gov (United States)

    Siegesmund, S.; Ruedrich, J.; Koch, A.

    2008-12-01

    The veneer cladding of the Oeconomicum (OEC, Göttingen), the State Theatre of Darmstadt (STD, Darmstadt) and of the State and University Library (SUB, Göttingen) is characterised by pronounced bowing after a short time of exposure. Direct comparison of bowing data related to measurements from 2000 to 2003 at the SUB clearly show that the amplitude in bowing had significantly increased. The bowing is different in intensity and orientation (concave, convex). The cladding material (Peccia marble, Rosa Estremoz marble and Carrara marble) are different in lattice preferred orientation, grain size distribution and grain interlocking. Depending on the bowing, panels may show cracks mostly initiated at the dowels. The percentage of visible cracks and breakouts increases with the amplitude of bowing except for the STD. Repetitive heating-cooling under dry conditions leads to considerable inelastic residual strain only after the first or second thermal cycle. The residual strain continuously increases again if water is present, whereby the moisture content after a thermal cycle has a certain impact on the decay rate. The water-enhanced thermal dilatation strongly correlates with the deterioration rate obtained from the laboratory bow test. Detailed petrophysical investigations provide evidence that with increasing bowing a decrease of mechanical properties (flexural strength or breaking load at dowel hole) occur. Marble degradation is also connected with the increase in porosity and a general shift of the maximum pore radii to larger pore sizes. On-site damage analyses were combined with laboratory tests of the bowing potential to constrain factors that may influence the risk failure. The experimental bowing data clearly demonstrate that after 40 heating cycles combined with the effect of moisture a certain impact on the decay rate is observed. In the case of demounted panels the bowing tests show that already strongly deformed panels from the building exhibit a lower

  1. Optimization of bow shape for a non ballast water ship

    Science.gov (United States)

    Van He, Ngo; Ikeda, Yoshiho

    2013-09-01

    In this research, a commercial CFD code "Fluent" was applied to optimization of bulbous bow shape for a non ballast water ships (NBS). The ship was developed at the Laboratory of the authors in Osaka Prefecture University, Japan. At first, accuracy of the CFD code was validated by comparing the CFD results with experimental results at towing tank of Osaka Prefecture University. In the optimizing process, the resistances acting on ships in calm water and in regular head waves were defined as the object function. Following features of bulbous bow shapes were considered as design parameters: volume of bulbous bow, height of its volume center, angle of bow bottom, and length of bulbous bow. When referring to the computed results given by the CFD like resistance, pressure and wave pattern made by ships in calm water and in waves, an optimal bow shape for ships was discovered by comparing the results in the series of bow shapes. In the computation on waves, the ship is in fully captured condition because shorter waves, λ/ L pp <0.6, are assumed.

  2. A Study on the Pometia tomentosa Community of Tropical Seasonal Rain Forest in Dahei Mountain, Lixian River Watershed,Southeastern Yunnan%滇东南李仙江大黑山热带季节性雨林番龙眼群落研究

    Institute of Scientific and Technical Information of China (English)

    周虹霞; 朱华; 王洪; 肖文祥

    2001-01-01

    滇东南绿春县李仙江大黑山番龙眼群落以无患子科的番龙眼和苏木科的无忧花为乔木层优势种,外貌以单叶、纸质、全缘、渐尖、中叶为主的常绿大、中高位芽植物组成为特征,层间木质藤本较丰富,属一种热带北缘的热带季节性雨林类型。该群落物种组成复杂,动态结构稳定,处于生长期。%The Pometia tomentosa forest in Dahei Mountain, Lixian RiverWatershed, southeastern Yunnan,is dominated by Pometia tomentosa and Saraca dives, and is charactered by evergreen megaphaenerophytes and mesophaenerophytes with simple ,chartaceous and entire mesophylls. With the conspicuous similarity on ecological and floristic characters to tropical rain forest of SE Asia, the forest in Dahei Mountain is considered as a type of tropical seasonal rain forest in the northern margin of tropical Asia. Furthermore, the distribution of trees in DBH class, the individual/ tree species relation and the frequency of tree species are enumerated.

  3. The static response of a bowed inclined hot wire

    Science.gov (United States)

    Smits, A. J.

    1984-01-01

    The directional sensitivity of a bowed, inclined hot wire is investigated using a simple model for the convective heat transfer. The static response is analyzed for subsonic and supersonic flows. It is shown that the effects of both end conduction and wire bowing are greater in supersonic flow. Regardless of the Mach number, however, these two phenomena have distinctly different effects; end conduction appears to be responsible for reducing the nonlinearity of the response, whereas bowing increases the directional sensitivity. Comparison with the available data suggests that the analysis is useful for interpreting the experimental results.

  4. 76 FR 12016 - MedBow-Routt Resource Advisory Committee

    Science.gov (United States)

    2011-03-04

    ... meeting. SUMMARY: The MedBow-Routt Resource Advisory Committee will meet in Walden, Colorado. The... will be held at Parks Ranger District, 100 Main Street, Walden, Colorado. Written comments should...

  5. Femoral bowing plane adaptation to femoral anteversion

    Directory of Open Access Journals (Sweden)

    Alp Akman

    2017-01-01

    Full Text Available Background: Femoral bowing plane (FBP is the unattended subject in the literature. More over the femoral shaft with its bowing is neglected in established anteversion determination methods. There is limited information about the relationship between FBP and anteversion. Thus we focused on this subject and hypothesized that there could be an adaptation of FBP to anteversion. Materials and Methods: FBP is determined on three-dimensional solid models derived from the left femoral computerized tomography data of 47 patients which were taken before for another reason and comparatively evaluated with anteversion. There were 20 women and 27 men. The mean age of patients was 56 years (range 21-84 years. Results: The anteversion values were found as the angle between a distal condylar axis (DCA and femoral neck anteversion axis (FNAA along an imaginary longitudinal femoral axis (LFA in the true cranio-caudal view. The FBP was determined as a plane that passes through the centre-points of three pre-determinated sections on the femoral shaft. The angles between DCA, FNAA and FBP were comparatively evaluated. The independent samples t-test was used for statistical analysis. At the end, it was found that FBP lies nearly perpendicular to the anteversion axis for the mean of our sample which is around 89° in females and 93° in males (range 78-102°. On the other hand, FBP does not lie close to the sagittal femoral plane (SFP; instead, there is an average 12.5° external rotation relative to the SFP. FBP is correlated well with anteversion in terms of FBP inclination from SFP and femoral torsion (i.e., angle between FBP and femoral neck anteversion axis (P0 < 0.001; r = 0.680 and r = −0.682, respectively. Combined correlation is perfect (R[2] = 1 as the FBP, SFP, and posterior femoral plane forms a triangle in the cranio-caudal view. Conclusions: We found that FBP adapts to anteversion. As FBP lies close to perpendicularity for the mean, femoral component

  6. Femoral bowing plane adaptation to femoral anteversion

    Science.gov (United States)

    Akman, Alp; Demirkan, Fahir; Sabir, Nuran; Oto, Murat; Yorukoglu, Cagdas; Kiter, Esat

    2017-01-01

    Background: Femoral bowing plane (FBP) is the unattended subject in the literature. More over the femoral shaft with its bowing is neglected in established anteversion determination methods. There is limited information about the relationship between FBP and anteversion. Thus we focused on this subject and hypothesized that there could be an adaptation of FBP to anteversion. Materials and Methods: FBP is determined on three-dimensional solid models derived from the left femoral computerized tomography data of 47 patients which were taken before for another reason and comparatively evaluated with anteversion. There were 20 women and 27 men. The mean age of patients was 56 years (range 21–84 years). Results: The anteversion values were found as the angle between a distal condylar axis (DCA) and femoral neck anteversion axis (FNAA) along an imaginary longitudinal femoral axis (LFA) in the true cranio-caudal view. The FBP was determined as a plane that passes through the centre-points of three pre-determinated sections on the femoral shaft. The angles between DCA, FNAA and FBP were comparatively evaluated. The independent samples t-test was used for statistical analysis. At the end, it was found that FBP lies nearly perpendicular to the anteversion axis for the mean of our sample which is around 89° in females and 93° in males (range 78–102°). On the other hand, FBP does not lie close to the sagittal femoral plane (SFP); instead, there is an average 12.5° external rotation relative to the SFP. FBP is correlated well with anteversion in terms of FBP inclination from SFP and femoral torsion (i.e., angle between FBP and femoral neck anteversion axis (P < 0.001; r = 0.680 and r = −0.682, respectively). Combined correlation is perfect (R2 = 1) as the FBP, SFP, and posterior femoral plane forms a triangle in the cranio-caudal view. Conclusions: We found that FBP adapts to anteversion. As FBP lies close to perpendicularity for the mean, femoral component positioning

  7. Mesoscale Surface Pressure and Temperature Features Associated with Bow Echoes

    Science.gov (United States)

    2010-01-01

    contain several bowing segments. These multiple segments could occur at the same time and be located within the same bow, such as the serial derecho ...Examination of derecho environments using proximity soundings. Wea. Forecasting, 16, 329–342. Fovell, R. G., 2002: Upstream influence of numerically...Se- vere Local Storms, Hyannis, MA, Amer. Meteor. Soc., 4.6. Johns, R. H., and W. D. Hirt, 1987: Derechos : Widespread con- vectively induced

  8. Dual-Frequency Operation of Bow-Tie Microstrip Antenna

    Institute of Scientific and Technical Information of China (English)

    钟顺时; 张需溥

    2005-01-01

    Characteristics of a single-feed dual-frequency bow-tie microstrip antenna are studied. By using the variation method, simple formulas for resonant frequencies of the bow-tie microstrip antenna are derived. It is shown that the dual-frequency ratio can be controlled easily by choosing the parameters of the antenna. This design gives compact antenna size and simple antenna structure. Experimental results are presented, verifying the validity of the design.

  9. Bow-shock Pulsar Wind Nebulae Passing Through Density Discontinuities

    CERN Document Server

    Yoon, Doosoo

    2016-01-01

    Bow-shock pulsar wind nebulae are a subset of pulsar wind nebulae that form when the pulsar has high velocity due to the natal kick during the supernova explosion. The interaction between the relativistic wind from the fast-moving pulsar and the interstellar medium produces a bow-shock and a trail, which are detectable in H$_{\\alpha}$ emission. Among such bow-shock pulsar wind nebulae, the Guitar Nebula stands out for its peculiar morphology, which consists of a prominent bow-shock head and a series of bubbles further behind. We present a scenario in which multiple bubbles can be produced when the pulsar encounters a series of density discontinuities in the ISM. We tested the scenario using 2-D and 3-D hydrodynamic simulations. The shape of the guitar nebula can be reproduced if the pulsar traversed a region of declining low density. We also show that if a pulsar encounters an inclined density discontinuity, it produces an asymmetric bow-shock head, consistent with observations of the bow-shock of the millise...

  10. Bow-tie diagrams for risk management in anaesthesia.

    Science.gov (United States)

    Culwick, M D; Merry, A F; Clarke, D M; Taraporewalla, K J; Gibbs, N M

    2016-11-01

    Bow-tie analysis is a risk analysis and management tool that has been readily adopted into routine practice in many high reliability industries such as engineering, aviation and emergency services. However, it has received little exposure so far in healthcare. Nevertheless, its simplicity, versatility, and pictorial display may have benefits for the analysis of a range of healthcare risks, including complex and multiple risks and their interactions. Bow-tie diagrams are a combination of a fault tree and an event tree, which when combined take the shape of a bow tie. Central to bow-tie methodology is the concept of an undesired or 'Top Event', which occurs if a hazard progresses past all prevention controls. Top Events may also occasionally occur idiosyncratically. Irrespective of the cause of a Top Event, mitigation and recovery controls may influence the outcome. Hence the relationship of hazard to outcome can be viewed in one diagram along with possible causal sequences or accident trajectories. Potential uses for bow-tie diagrams in anaesthesia risk management include improved understanding of anaesthesia hazards and risks, pre-emptive identification of absent or inadequate hazard controls, investigation of clinical incidents, teaching anaesthesia risk management, and demonstrating risk management strategies to third parties when required.

  11. Numerical simulations of Mach stem formation via intersecting bow shocks

    Science.gov (United States)

    Hansen, E. C.; Frank, A.; Hartigan, P.; Yirak, K.

    2015-12-01

    Hubble Space Telescope observations show bright knots of Hα emission within outflowing young stellar jets. Velocity variations in the flow create secondary bow shocks that may intersect and lead to enhanced emission. When the bow shocks intersect at or above a certain critical angle, a planar shock called a Mach stem is formed. These shocks could produce brighter Hα emission since the incoming flow to the Mach stem is parallel to the shock normal. In this paper we report first results of a study using 2-D numerical simulations designed to explore Mach stem formation at the intersection of bow shocks formed by hypersonic "bullets" or "clumps". Our 2-D simulations show how the bow shock shapes and intersection angles change as the adiabatic index γ changes. We show that the formation or lack of a Mach stem in our simulations is consistent with the steady-state Mach stem formation theory. Our ultimate goal, which is part of an ongoing research effort, is to characterize the physical and observational consequences of bow shock intersections including the formation of Mach stems.

  12. Social complexity and the bow in the Eastern Woodlands.

    Science.gov (United States)

    Blitz, John H; Porth, Erik S

    2013-01-01

    Bingham and Souza have presented an evolutionary theory that specifies a causal relationship between the advent of powerful projectile weapons such as the bow and radical rearrangements in social relations and histories. They propose that the acquisition of weapons that permitted humans to kill at ever-increasing distances provided the coercive means to suppress conflicts of interest among nonkin, self-interested individuals in social groups, thus paving the way for greater social complexity. An unprecedented reduction in projectile point size identifies the arrival of the bow ca. A.D. 300 in the Eastern Woodlands of North America, which initiated a causal chain of cultural changes. In the Midwest, the bow, combined with food production, precipitated the decline of Hopewell by conferring household autonomy and dispersal, which at first suppressed social complexity, but later created conditions favorable to maize intensification. In the lower Southeast, where food production was unimportant, populations aggregated at concentrated wild-food sources, and the bow did not confer household autonomy. The relationship between the bow and social complexity varied under different environmental, social, and historical conditions.

  13. BowTieBuilder: modeling signal transduction pathways

    Directory of Open Access Journals (Sweden)

    Schröder Adrian

    2009-06-01

    Full Text Available Abstract Background Sensory proteins react to changing environmental conditions by transducing signals into the cell. These signals are integrated into core proteins that activate downstream target proteins such as transcription factors (TFs. This structure is referred to as a bow tie, and allows cells to respond appropriately to complex environmental conditions. Understanding this cellular processing of information, from sensory proteins (e.g., cell-surface proteins to target proteins (e.g., TFs is important, yet for many processes the signaling pathways remain unknown. Results Here, we present BowTieBuilder for inferring signal transduction pathways from multiple source and target proteins. Given protein-protein interaction (PPI data signaling pathways are assembled without knowledge of the intermediate signaling proteins while maximizing the overall probability of the pathway. To assess the inference quality, BowTieBuilder and three alternative heuristics are applied to several pathways, and the resulting pathways are compared to reference pathways taken from KEGG. In addition, BowTieBuilder is used to infer a signaling pathway of the innate immune response in humans and a signaling pathway that potentially regulates an underlying gene regulatory network. Conclusion We show that BowTieBuilder, given multiple source and/or target proteins, infers pathways with satisfactory recall and precision rates and detects the core proteins of each pathway.

  14. Bow and Oblique Shock Formation in Soap Film

    Science.gov (United States)

    Kim, Ildoo; Mandre, Shreyas; Sane, Aakash

    2015-11-01

    In recent years, soap films have been exploited primarily to approximate two-dimensional flows while their three-dimensional character is relatively unattended. An example of the three-dimensional character of the flow in a soap film is the observed Marangoni shock wave when the flow speed exceeds the wave speed. In this study, we investigated the formation of bow and oblique shocks in soap films generated by wedges with different deflection angles. When the wedge deflection angle is small and the film flows fast, oblique shocks are observed. When the oblique shock cannot exists, bow shock is formed upstream the wedge. We characterized the oblique shock angle as a function of the wedge deflection angle and the flow speed, and we also present the criteria for transition between bow and oblique Marangoni shocks in soap films.

  15. Foreshock ions observed behind the Martian bow shock

    Science.gov (United States)

    Frahm, R. A.; Yamauchi, M.; Winningham, J. D.; Lundin, R.; Sharber, J. R.; Nilsson, H.; Coates, A. J.

    2016-08-01

    The Mars Express Analyzer of Space Plasmas and Energetic Atoms experiment contains ion and electron instruments for conducting plasma measurements. On January 23, 2012, during in-bound travel of Mars Express in the southern hemisphere of Mars from its dawn side toward periapsis at dusk, the plasma instruments measured foreshock-like ion beams extending from outside the bow shock and into the magnetosphere, continuing to a distance of about a proton gyroradius from the bow shock. These ion beams were mostly protons, were observed to have energies greater than solar wind protons, and were not gyrating, in agreement with reflections of the solar wind proton beam. Furthermore, in the foreshock region the ion energy gradually decreased toward the magnetosheath, in agreement with an acceleration by outward-directed electric field in the bowshock. The observations also suggest that this electric field exists even inside the magnetosheath within the distance of a proton gyroradius from the bow shock.

  16. Planetary Embryo Bow Shocks as a Mechanism for Chondrule Formation

    CERN Document Server

    Mann, Christopher R; Morris, Melissa M

    2016-01-01

    We use radiation hydrodynamics with direct particle integration to explore the feasibility of chondrule formation in planetary embryo bow shocks. The calculations presented here are used to explore the consequences of a Mars-size planetary embryo traveling on a moderately excited orbit through the dusty, early environment of the solar system. The embryo's eccentric orbit produces a range of supersonic relative velocities between the embryo and the circularly orbiting gas and dust, prompting the formation of bow shocks. Temporary atmospheres around these embryos, which can be created via volatile outgassing and gas capture from the surrounding nebula, can non-trivially affect thermal profiles of solids entering the shock. We explore the thermal environment of solids that traverse the bow shock at different impact radii, the effects that planetoid atmospheres have on shock morphologies, and the stripping efficiency of planetoidal atmospheres in the presence of high relative winds. Simulations are run using adia...

  17. Featured Image: A Search for Stellar Bow Shock Nebulae

    Science.gov (United States)

    Kohler, Susanna

    2017-02-01

    These dynamic infrared images (click for the full view!) reveal what are known as bow shock nebulae nebulae that form at the interface between the interstellar medium and the stellar wind from a high-speed star zipping through the galaxy (the arrows show the direction of motion of the star). When the relative speed between the two is supersonic, an arc-shaped bow shock forms ahead of the star, like the six prototypical ones pictured here. A team of scientists led by Henry Kobulnicky (University of Wyoming) has recently searched through survey data from the Spitzer Space Telescope and the Wide Field Infrared Explorer (WISE) to build a catalog of more than 700 such bow-shock nebula candidates, the vast majority of which are new discoveries. To find out more about their sample, check out the paper below!CitationHenry A. Kobulnicky et al 2016 ApJS 227 18. doi:10.3847/0067-0049/227/2/18

  18. Transport of Solar Wind Across Earth's Bow Shock

    Science.gov (United States)

    Parks, G. K.; Lee, E.; Yang, Z.; Liu, Y.; Fu, S.; Canu, P.; Goldstein, M. L.; Dandouras, I. S.; Reme, H.; Hong, J.

    2015-12-01

    Observations have established that about 20% of the solar wind (SW) is reflected and 80% directly transmitted across Earth's bow shock (Skopke et al, Adv. Space Sci., 15, No. 8/9, 269, 1995). The transmitted SW is not immediately thermalized and the magnetosheath plasma distribution can remain non-Maxwellian for a long time. Cluster observations have further established that most of the magnetosheath bulk flow remains super-Alfvenic except in the polar altitudes near the cusp region (Longmore et al., Anna. Geophysicae, 23, 3351-3364, 2005). We have studied SW ion distributions before and after entering the bow shock to examine the details of the solar wind-bow shock interaction. Preliminary findings indicate that a typical SW H+ beam with thermal kT ~10 eV drifting at 400 km/s in front of the bow shock appears as ~12 eV beam drifting at 250 km/s after it penetrates the shock barrier. The small kT increase is possibly due to wave-particle interaction at the boundary. While the He++ ion beam kT behaves similarly as H+ ions, the drift velocities of He++ ions do not always slow down as H+ ions. These observations indicate the physics of SW-bow shock interaction is much more complicated than the models that explain SW slow down as resulting from an electrostatic potential at the shock that decelerates the SW. We have started PIC simulation of SW transport across the bow shock and the results will be presented together with observations.

  19. Crushing of ship bows in head-on collision

    DEFF Research Database (Denmark)

    Ocakli, H.; Zhang, S.; Pedersen, Preben Terndrup

    2004-01-01

    Semi-analytical methods for analysis of plate crushing and ship bow damage in head-on collisions are developed in this paper. Existing experimental and theoretical studies for crushing analysis of plated structures are summarized and compared. Simple formulae for determining the crushing force....... The approach developed can be used easily to determine the crushing resistance and damage extent of the ship bow when ship length and collision speed are known. The method can be used in probabilistic analysis of damage extents in ship collisions where a large number of calculations are generally required....

  20. Geologic, geomorphic, and meteorological aspects of debris flows triggered by Hurricanes Frances and Ivan during September 2004 in the Southern Appalachian Mountains of Macon County, North Carolina (southeastern USA)

    Science.gov (United States)

    Wooten, R.M.; Gillon, K.A.; Witt, A.C.; Latham, R.S.; Douglas, T.J.; Bauer, J.B.; Fuemmeler, S.J.; Lee, L.G.

    2008-01-01

    In September 2004, rain from the remnants of Hurricanes Frances and Ivan triggered at least 155 landslides in the Blue Ridge Mountains of North Carolina. At least 33 debris flows occurred in Macon County, causing 5 deaths, destroying 16 homes, and damaging infrastructure. We mapped debris flows and debris deposits using a light-detecting and ranging digital elevation model, remote imagery and field studies integrated in a geographic information system. Evidence of past debris flows was found at all recent debris flow sites. Orographic rainfall enhancement along topographic escarpments influenced debris flow frequency at higher elevations. A possible trigger for the Wayah and fatal Peeks Creek debris flows was a spiral rain band within Ivan that moved across the area with short duration rainfall rates of 150-230 mm/h. Intersecting bedrock structures in polydeformed metamorphic rock influence the formation of catchments within structural-geomorphic domains where debris flows originate. ?? 2007 Springer-Verlag.

  1. Southeastern Science Policy Colloquium

    Energy Technology Data Exchange (ETDEWEB)

    Humphries, F.

    1995-06-22

    This conference covers four main topics: (1) Southeastern Labor Market and its Impact on Corporate/Industry Development; (2) New Issues for Science and Technology in the Year 2000 and Beyond; (3) The Role of Academia in Developing the Labor Force of the Southeast; and (4) K-12 Education: Challenges for the 21st Century.

  2. Application of Bow-tie methodology to improve patient safety.

    Science.gov (United States)

    Abdi, Zhaleh; Ravaghi, Hamid; Abbasi, Mohsen; Delgoshaei, Bahram; Esfandiari, Somayeh

    2016-05-09

    Purpose - The purpose of this paper is to apply Bow-tie methodology, a proactive risk assessment technique based on systemic approach, for prospective analysis of the risks threatening patient safety in intensive care unit (ICU). Design/methodology/approach - Bow-tie methodology was used to manage clinical risks threatening patient safety by a multidisciplinary team in the ICU. The Bow-tie analysis was conducted on incidents related to high-alert medications, ventilator associated pneumonia, catheter-related blood stream infection, urinary tract infection, and unwanted extubation. Findings - In total, 48 potential adverse events were analysed. The causal factors were identified and classified into relevant categories. The number and effectiveness of existing preventive and protective barriers were examined for each potential adverse event. The adverse events were evaluated according to the risk criteria and a set of interventions were proposed with the aim of improving the existing barriers or implementing new barriers. A number of recommendations were implemented in the ICU, while considering their feasibility. Originality/value - The application of Bow-tie methodology led to practical recommendations to eliminate or control the hazards identified. It also contributed to better understanding of hazard prevention and protection required for safe operations in clinical settings.

  3. A Study of Uranus' Bow Shock Motions Using Langmuir Waves

    Science.gov (United States)

    Xue, S.; Cairns, I. H.; Smith, C. W.; Gurnett, D. A.

    1996-01-01

    During the Voyager 2 flyby of Uranus, strong electron plasma oscillations (Langmuir waves) were detected by the plasma wave instrument in the 1.78-kHz channel on January 23-24, 1986, prior to the inbound bow shock crossing. Langmuir waves are excited by energetic electrons streaming away from the bow shock. The goal of this work is to estimate the location and motion of Uranus' bow shock using Langmuir wave data, together with the spacecraft positions and the measured interplanetary magnetic field. The following three remote sensing analyses were performed: the basic remote sensing method, the lag time method, and the trace-back method. Because the interplanetary magnetic field was highly variable, the first analysis encountered difficulties in obtaining a realistic estimation of Uranus' bow shock motion. In the lag time method developed here, time lags due to the solar wind's finite convection speed are taken into account when calculating the shock's standoff distance. In the new trace-back method, limits on the standoff distance are obtained as a function of time by reconstructing electron paths. Most of the results produced by the latter two analyses are consistent with predictions based on the standard theoretical model and the measured solar wind plasma parameters. Differences between our calculations and the theoretical model are discussed.

  4. Analysis of the Giacobini-Zinner bow wave

    Energy Technology Data Exchange (ETDEWEB)

    Smith, E.J.; Slavin, J.A.; Bame, S.J.; Thomsen, M.F.; Cowley, S.W.H.; Richardson, I.G.; Hovestadt, D.; Ipavich, F.M.; Ogilvie, K.W.; Coplan, M.A.

    1986-01-01

    The cometary bow wave of P/Giacobini-Zinner has been analyzed using the complete set of ICE field and particle observations to determine if it is a shock. Changes in the magnetic field and plasma flow velocities from upstream to downstream have been analyzed to determine the direction of the normal and the propagation velocity of the bow wave. The velocity has then been compared with the fast magnetosonic wave speed upstream to derive the Mach number and establish whether it is ''supersonic'', i.e., a shock, or ''subsonic,'' i.e., a large amplitude wave. The various measurements have also been compared with values derived from a Rankine-Hugoniot analysis. The results indicate that, inbound, the bow wave is a shock with M = 1.5. Outbound, a subsonic mach number is obtained, however, arguments are presented that the bow wave is also likely to be a shock at this location. 11 refs., 4 figs., 2 tabs.

  5. Modeling non-thermal emission from stellar bow shocks

    CERN Document Server

    Pereira, V; Miceli, M; Bonito, R; de Castro, E

    2016-01-01

    Runaway O- and early B-type stars passing throughout the interstellar medium at supersonic velocities and characterized by strong stellar winds may produce bow shocks that can serve as particle acceleration sites. Previous theoretical models predict the production of high energy photons by non-thermal radiative processes, but their efficiency is still debated. We aim to test and explain the possibility of emission from the bow shocks formed by runaway stars traveling through the interstellar medium by using previous theoretical models. We apply our model to AE Aurigae, the first reported star with an X-ray detected bow shock, to BD+43 3654, in which the observations failed in detecting high energy emission, and to the transition phase of a supergiant star in the late stages of its life.From our analysis, we confirm that the X-ray emission from the bow shock produced by AE Aurigae can be explained by inverse Compton processes involving the infrared photons of the heated dust. We also predict low high energy fl...

  6. Fatigue analysis of the bow structure of FPSO

    Institute of Scientific and Technical Information of China (English)

    HU Zhi-qiang; GAO Zhen; GU Yong-ning

    2003-01-01

    The bow structure of FPSO moored by the single mooring system is rather complicated. There are many potential hot spots in connection parts of structures between the mooring support frame and the forecastle. Mooring forces, which are induced by wave excitation and transferred by the YOKE and the mooring support frame, may cause fatigue damage to the bow structure. Different from direct wave-induced-forces, the mooring force consists of wave frequency force (WF) and 2nd draft low frequency force (LF)[3], which are represented by two sets of short-term distribution respectively. Based on two sets of short-term distribution of mooring forces obtained by the model test, the fatigue damage of the bow structure of FPSO is analyzed, with emphasis on two points. One is the procedure and position selection for fatigue check, and the other is the application of new formulae for the calculation of accumulative fatigue damage caused by two sets of short-term distribution of hot spot stress range. From the results distinguished features of fatigue damage to the FPSO's bow structure can be observed.

  7. Numerical Simulations of Mach Stem Formation via Intersecting Bow Shocks

    CERN Document Server

    Hansen, Edward C; Hartigan, Patrick

    2014-01-01

    Hubble Space Telescope observations show bright knots of H$\\alpha$ emission within outflowing young stellar jets. Velocity variations in the flow create secondary bow shocks that may intersect and lead to enhanced emission. When the bow shocks intersect at or above a certain critical angle, a planar shock called a Mach stem is formed. These shocks could produce brighter H$\\alpha$ emission since the incoming flow to the Mach stem is parallel to the shock normal. In this paper we report first results of a study using 2-D numerical simulations designed to explore Mach stem formation at the intersection of bow shocks formed by hypersonic "bullets" or "clumps". Our 2-D simulations show how the bow shock shapes and intersection angles change as the adiabatic index $\\gamma$ changes. We show that the formation or lack of a Mach stem in our simulations is consistent with the steady-state Mach stem formation theory. Our ultimate goal, which is part of an ongoing research effort, is to characterize the physical and obse...

  8. THE JET-DRIVEN BOW SHOCK IN OUTFLOWS

    Institute of Scientific and Technical Information of China (English)

    ZhangQing; ZhengXingwu

    1999-01-01

    Recent high resolution observations show the high collimated bipolar molecular outflows from young stellar objects, such as NGC 2 264G and NGC 2 024. Existing models can not yet give complete interpretations of the structure and properties of the observed flow. Here, we propose a jet-driven bow

  9. Small Arms of the Scythians. On the Time of Sigmoid Bow Appearance in Eastern Europe

    Directory of Open Access Journals (Sweden)

    Lukyashko Sergey Ivanovich

    2015-12-01

    Full Text Available Horse archers well-known in the ancient world used composite sigmoid bows for shooting (archery, the specific constructive features of which have been studied by the researchers. This type of a bow was convergently formed in Eastern China in the middle of the 2nd millennium B.C. and in the North Caucasus in the middle of the 4th millennium B.C. It gets transferred to the Northern Black Sea Region by the Scythians in the late 7th - early 6th centuries B.C. that resulted in the dramatic transformation of arrowheads’ types. The Greeks became aware of this weapon in the last third of the 6th century B.C. Bows can be divided into simple and complex ones. The simple bows are made from one solid bar, while the complex bows are made of several layers of different wood species. Composite bows are constructed from a few consequently connected bars. These types also include a reinforced bow – the bow springing qualities of which are reinforced by bone or tendon plates. Since the ancient masters combined different production methods, the definition of a composite reinforced bow can be found in the literature. European small arms development was focused on improving a simple bow. The strength of such bow was achieved by its size. However, massive bows are unsuitable for firing from a horse. Therefore, in cultures associated with the development of riding the search of methods of bow strength increase at the condition of reducing its size, was going on. In Asia, the focus was made on the material rather than shoulders design. As a result, complex composite bows appear in the East, which were made from several pieces of wood, connected with the central part of the handle at an angle. After the appearance of the Scythians in the middle East the angular design of bows was replaced by a sigmoid shape (scythicus acrus.

  10. Geology and mineral resources of the Sheldon-Hart Mountain National Wildlife Refuge Complex (Oregon and Nevada), the Southeastern Oregon and North-Central Nevada, and the Southern Idaho and Northern Nevada (and Utah) Sagebrush Focal Areas: Chapter B in Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming

    Science.gov (United States)

    Vikre, Peter G.; Benson, Mary Ellen; Bleiwas, Donald I.; Colgan, Joseph P.; Cossette, Pamela M.; DeAngelo, Jacob; Dicken, Connie L.; Drake, Ronald M.; du Bray, Edward A.; Fernette, Gregory L.; Glen, Jonathan M.G.; Haacke, Jon E.; Hall, Susan M.; Hofstra, Albert H.; John, David A.; Ludington, Stephen; Mihalasky, Mark J.; Rytuba, James J.; Shaffer, Brian N.; Stillings, Lisa L.; Wallis, John C.; Williams, Colin F.; Yager, Douglas B.; Zürcher, Lukas

    2016-10-04

    This report is temporarily unavailableSummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpose of the proposed action is to protect the greater sage-grouse (Centrocercus urophasianus) and its habitat from potential adverse effects of locatable mineral exploration and mining. The U.S. Geological Survey Sagebrush Mineral-Resource Assessment (SaMiRA) project was initiated in November 2015 and supported by the Bureau of Land Management to (1) assess locatable mineral-resource potential and (2) to describe leasable and salable mineral resources for the seven SFAs and Nevada additions.This chapter summarizes the current status of locatable, leasable, and salable mineral commodities and assesses the potential of selected locatable minerals in lands proposed for withdrawal that span the Nevada, Oregon, Idaho, and Utah borders. In this report, the four study areas evaluated were (1) the Sheldon-Hart Mountain National Wildlife Refuge Complex SFA in Washoe County, Nevada, and Harney and Lake Counties, Oregon; (2) the Southeastern Oregon and North-Central Nevada SFA in Humboldt County, Nevada, and Harney and Malheur Counties, Oregon; (3) the Southern Idaho and Northern Nevada SFA in Cassia, Owyhee, and Twin Falls Counties, Idaho, Elko County, Nevada, and Box Elder County, Utah; and (4) the Nevada additions in Humboldt and Elko Counties, Nevada.

  11. Geology and mineral resources of the Sheldon-Hart Mountain National Wildlife Refuge Complex (Oregon and Nevada), the Southeastern Oregon and North-Central Nevada, and the Southern Idaho and Northern Nevada (and Utah) Sagebrush Focal Areas: Chapter B in Mineral resources of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming

    Science.gov (United States)

    Vikre, Peter G.; Benson, Mary Ellen; Bleiwas, Donald I.; Colgan, Joseph P.; Cossette, Pamela M.; DeAngelo, Jacob; Dicken, Connie L.; Drake, Ronald M.; du Bray, Edward A.; Fernette, Gregory L.; Glen, Jonathan M.G.; Haacke, Jon E.; Hall, Susan M.; Hofstra, Albert H.; John, David A.; Ludington, Stephen; Mihalasky, Mark J.; Rytuba, James J.; Shaffer, Brian N.; Stillings, Lisa L.; Wallis, John C.; Williams, Colin F.; Yager, Douglas B.; Zürcher, Lukas

    2016-10-04

    SummaryThe U.S. Department of the Interior has proposed to withdraw approximately 10 million acres of Federal lands from mineral entry (subject to valid existing rights) from 12 million acres of lands defined as Sagebrush Focal Areas (SFAs) in Idaho, Montana, Nevada, Oregon, Utah, and Wyoming (for further discussion on the lands involved see Scientific Investigations Report 2016–5089–A). The purpose of the proposed action is to protect the greater sage-grouse (Centrocercus urophasianus) and its habitat from potential adverse effects of locatable mineral exploration and mining. The U.S. Geological Survey Sagebrush Mineral-Resource Assessment (SaMiRA) project was initiated in November 2015 and supported by the Bureau of Land Management to (1) assess locatable mineral-resource potential and (2) to describe leasable and salable mineral resources for the seven SFAs and Nevada additions.This chapter summarizes the current status of locatable, leasable, and salable mineral commodities and assesses the potential of selected locatable minerals in lands proposed for withdrawal that span the Nevada, Oregon, Idaho, and Utah borders. In this report, the four study areas evaluated were (1) the Sheldon-Hart Mountain National Wildlife Refuge Complex SFA in Washoe County, Nevada, and Harney and Lake Counties, Oregon; (2) the Southeastern Oregon and North-Central Nevada SFA in Humboldt County, Nevada, and Harney and Malheur Counties, Oregon; (3) the Southern Idaho and Northern Nevada SFA in Cassia, Owyhee, and Twin Falls Counties, Idaho, Elko County, Nevada, and Box Elder County, Utah; and (4) the Nevada additions in Humboldt and Elko Counties, Nevada.

  12. Magnetic field fluctuations across the Earth’s bow shock

    Directory of Open Access Journals (Sweden)

    A. Czaykowska

    Full Text Available We present a statistical analysis of 132 dayside (LT 0700-1700 bow shock crossings of the AMPTE/IRM spacecraft. We perform a superposed epoch analysis of low frequency, magnetic power spectra some minutes up-stream and downstream of the bow shock. The events are devided into categories depending on the angle θBn between bow shock normal and interplanetary magnetic field, and on plasma-β. In the foreshock upstream of the quasi-parallel bow shock, the power of the magnetic fluctuations is roughly 1 order of magnitude larger (δB ~ 4 nT for frequencies 0.01–0.04 Hz than upstream of the quasi-perpendicular shock. There is no significant difference in the magnetic power spectra upstream and downstream of the quasi-parallel bow shock; only at the shock itself, is the magnetic power enhanced by a factor of 4. This enhancement may be due to either an amplification of convecting upstream waves or to wave generation at the shock interface. On the contrary, downstream of the quasi-perpendicular shock, the magnetic wave activity is considerably higher than upstream. Down-stream of the quasi-perpendicular low-β bow shock, we find a dominance of the left-hand polarized component at frequencies just below the ion-cyclotron frequency, with amplitudes of about 3 nT. These waves are identified as ion-cyclotron waves, which grow in a low-β regime due to the proton temperature anisotropy. We find a strong correlation of this anisotropy with the intensity of the left-hand polarized component. Downstream of some nearly perpendicular (θBn ≈ 90° high-β crossings, mirror waves are identified. However, there are also cases where the conditions for mirror modes are met downstream of the nearly perpendicular shock, but no mirror waves are observed.

    Key words. Interplanetary physics (plasma waves and turbulence – Magnetospheric physics (magnetosheath; plasma waves and

  13. Reconnaissance geology and geochronology of the Precambrian of the Granite Mountains, Wyoming

    Science.gov (United States)

    Peterman, Zell E.; Hildreth, Robert A.

    1978-01-01

    The Precambrian of the western part of the Granite Mountains, Wyoming, contains a metamorphic complex of gneisses, schists, and amphibolites that were derived through amphibolite-grade metamorphism from a sedimentary-volcanic sequence perhaps similar to that exposed in the southeastern Wind River Mountains. Whole-rock Rb-Sr dating places the time of metamorphism at 2,860?80 million years. A high initial 87Sr/ 86 S r ratio of 0.7048 suggests that either the protoliths or the source terrane of the sedimentary component is several hundred million years older than the time of metamorphism. Following an interval of 300:t100 million years for which the geologic record is lacking or still undeciphered, the metamorphic complex was intruded by a batholith and satellite bodies of medium- to coarse-grained, generally massive biotite granite and related pegmatite and aplite. The main body of granite is dated at 2,550?60 million years by the Rb-Sr method. Limited data suggest that diabase dikes were emplaced and nephrite veins were formed only shortly after intrusion of the granite. Emplacement of the granite at about 2,550 million years ago appears to be related to a major period of regional granitic plutonism in the Precambrian of southern and western Wyoming. Granites, in the strict sense, that are dated between 2,450 and 2,600 million years occur in the Teton Range, the Sierra Madre, the Medicine Bow Mountains and the Laramie Range. This episode of granitic plutonism occured some 50 to 100 million years later than the major tonalitic to granitic plutonism in the Superior province of northern Minnesota and adjacent Ontario-the nearest exposed Precambrian W terrane that is analogous to the Wyoming province. Initial 87Sr / 86Sr ratios of some of the Wyoming granites are higher than expected if the rocks had been derived from juvenile magmas and it is likely that older crustal rocks were involved to some degree in the generation of these granites. Slightly to highly disturbed

  14. MOUNTAINS UNITE

    Directory of Open Access Journals (Sweden)

    Svitlana Dovbenko

    2015-04-01

    Full Text Available Schools in the Ukrainian Carpathian mountain region work in specific conditions. They have original traditions, a special nature of learning and work. Indeed, because of a remote location mountain village school becomes the center for a cultural and spiritual life. Of course, it is related to a present social and economic situation in the country and a slow progress of society. Therefore, we need to look at mountain school with a broader angle, help it in comprehensive development of an individual and ensure an availability of quality education for children living in mountainous areas. Here we should talk about learning as well as laying the foundations for a life success. The international research project Mountain School. Status. Problems. Prospects for Development. Is established to help solve these problems. Precarpathian National University is an active member of the project.

  15. Southeastern Scarp of Olympus Mons

    Science.gov (United States)

    2002-01-01

    (Released 4 June 2002) The Science The movement pathways of molten rock, or lava, is demonstrated in this image of a portion of Olympus Mons, the largest volcano in our solar system. These now-solid lava flows all show nearly the same orientation, having flowed from northeast to southwest, down the slope of the volcano's southeastern flank. Throughout the image, narrow pairs of lineaments can be observed ? these are called levees, and are essentially channel walls formed by the solidification and buildup of the edges of the lava flows. We can determine that the high-standing mountains must be older than the flows because they blocked their passage, causing the flows to change direction and go around the taller mountains. As in other THEMIS images, the lack of bright-dark contrast in this image indicates that a layer of dust covers these surfaces. The surfaces of the lava flows are virtually uncratered, attesting to the relatively recent formation of the flows, where ?recent? is within the last 500 million years or so. Several meteorites found on Earth appear to have come from volcanic regions on Mars ? their ages are as young as 180 million years, leading many scientists to suggest that volcanoes of the Tharsis region, including Olympus Mons, may be the source regions of these meteorites. A prominent pear-shaped bowl is apparent on a hill in the lower right third of the image ? the collapse and mass movement of material down slope, which also formed a debris pile below and southeast of the bowl, likely formed this feature. The Story Millions and millions of years ago, a huge impact blasted a crater into the surface of Mars, sending particles of the Martian surface scattering into space at great speeds, where they spent millions and millions of years calmly in space before encountering a nearby orbiting planet: our own planet Earth. Hurtling down through Earth's atmosphere, these pieces of Mars landed in various regions of our world and were discovered by modern

  16. Mass-loading of bow shock pulsar wind nebulae

    CERN Document Server

    Morlino, G; Vorster, M

    2016-01-01

    We investigate the dynamics of bow shock nebulae created by pulsars moving supersonically through a partially ionized interstellar medium. A fraction of interstellar neutral hydrogen atoms penetrating into the tail region of a pulsar wind will undergo photo-ionization due to the UV light emitted by the nebula, with the resulting mass loading dramatically changing the flow dynamics of the light leptonic pulsar wind. Using a quasi 1-D hydrodynamic model of relativistic flow we find that if a relatively small density of neutral hydrogen, as low as $10^{-4}$ cm$^{-3}$, penetrate inside the pulsar wind, this is sufficient to strongly affect the tail flow. Mass loading leads to the fast expansion of the pulsar wind tail, making the tail flow intrinsically non-stationary. The shapes predicted for the bow shock nebulae compare well with observations, both in H$\\alpha$ and X-rays.

  17. Face bow and articulator for planning orthognathic surgery: 2 articulator.

    Science.gov (United States)

    Walker, Fraser; Ayoub, Ashraf F; Moos, Khursheed F; Barbenel, Joseph

    2008-10-01

    Patients who require orthognathic surgery may have asymmetry of the position of the temporomandibular joints relative to the maxilla, which is impossible to reproduce on the current semiadjustable articulators used for surgical planning. We describe a highly-adjustable spirit level orthognathic face bow that allows records to be made of patients with asymmetrical maxillae. The orthognathic articulator also allows the position of the condylar components of the articulator to be adjusted in three dimensions. The use of the new face bow and articulator made it possible to mount the dental casts of asymmetrical faces to reproduce their clinical appearance. The devices were evaluated by comparing the measurements of anatomical variables obtained from cephalometric radiographs with equivalent values obtained from the orthognathic articulator and casts mounted on the articulator. Although the measurements showed significant intersubject variability, the angle between the horizontal and maxillary occlusal plane, occlusal cant angle, and intercondylar widths, were not significantly different.

  18. Breaking the BOWS Watermarking System: Key Guessing and Sensitivity Attacks

    Directory of Open Access Journals (Sweden)

    Comesaña Pedro

    2007-01-01

    Full Text Available From December 15, 2005 to June 15, 2006, the watermarking community was challenged to remove the watermark from 3 different 512×512 watermarked images while maximizing the peak signal-to-noise ratio (PSNR measured by comparing the watermarked signals with their attacked counterparts. This challenge, which bore the inviting name of Break Our Watermarking System (BOWS, had as its main objective to enlarge the current knowledge on attacks to watermarking systems. In this paper, the main results obtained by the authors when attacking the BOWS system are presented and compared with strategies followed by other groups. Essentially, two different approaches have been followed: exhaustive search of the secret key and blind sensitivity attacks.

  19. Mass-loading of bow shock pulsar wind nebulae

    CERN Document Server

    Morlino, G; Vorster, M J

    2015-01-01

    We investigate the dynamics of bow shock nebulae created by pulsars moving supersonically through a partially ionized interstellar. A fraction of interstellar neutrals penetrating into the tail region of a pulsar wind will undergo photo-ionization due to the UV light emitted by the nebula, with the resulting mass loading dramatically changing the flow dynamics of the light leptonic pulsar wind. Using a quasi 1-D hydrodynamic model of both non-relativistic and relativistic flow, and focusing on scales much larger than the stand-off distance, we find that a relatively small density of neutrals, as low as $n_{\\rm ISM}=10^{-4}\\,\\text{cm}^{-3}$, is sufficient to strongly affect the tail flow. Mass loading leads to the fast expansion of the pulsar wind tail, making the tail flow intrinsically non-stationary. The shapes predicted for the bow shock nebulae compare well with observations, both in H$\\alpha$ and X-rays.

  20. Arctic Bowyery – the Use of Compression Wood in Bows in the Subarctic and Arctic Regions of Eurasia and America

    Directory of Open Access Journals (Sweden)

    Marcus Lepola

    2015-06-01

    Full Text Available This paper is a study of the traditional use of a special kind of wood in bow construction in Eurasia and North America. This special kind of wood, called compression wood and coming from coniferous trees, has unique qualities that makes it suitable for bow construction. Bows made using this special wood have been referred to as Finno-Ugric bows, Sámi bows, Two-Wood bows and Eurasia laminated bows. These bows appear to have developed from archaic forms of compression wood self bows that were made from a single piece of wood. Recently features similar to the Eurasian compression wood bows have been discovered in bows originating from Alaska, and the use of compression wood for bow manufacture has been known to some Canadian Inuit groups. This paper addresses the origin and possible diffusion pattern of this innovation in bow technology in Eurasia and suggests a timeframe and a possible source for the transfer of this knowledge to North America. This paper also discusses the role of the Asiatic composite bow in the development of bows in Eurasia.

  1. PLANETARY EMBRYO BOW SHOCKS AS A MECHANISM FOR CHONDRULE FORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Christopher R.; Boley, Aaron C. [Department of Physics and Astronomy University of British Columbia Vancouver, BC V6T 1Z1 (Canada); Morris, Melissa A. [Physics Department State University of New York at Cortland Cortland, NY 13045 (United States)

    2016-02-20

    We use radiation hydrodynamics with direct particle integration to explore the feasibility of chondrule formation in planetary embryo bow shocks. The calculations presented here are used to explore the consequences of a Mars-size planetary embryo traveling on a moderately excited orbit through the dusty, early environment of the solar system. The embryo’s eccentric orbit produces a range of supersonic relative velocities between the embryo and the circularly orbiting gas and dust, prompting the formation of bow shocks. Temporary atmospheres around these embryos, which can be created via volatile outgassing and gas capture from the surrounding nebula, can non-trivially affect thermal profiles of solids entering the shock. We explore the thermal environment of solids that traverse the bow shock at different impact radii, the effects that planetoid atmospheres have on shock morphologies, and the stripping efficiency of planetoidal atmospheres in the presence of high relative winds. Simulations are run using adiabatic and radiative conditions, with multiple treatments for the local opacities. Shock speeds of 5, 6, and 7 km s{sup −1} are explored. We find that a high-mass atmosphere and inefficient radiative conditions can produce peak temperatures and cooling rates that are consistent with the constraints set by chondrule furnace studies. For most conditions, the derived cooling rates are potentially too high to be consistent with chondrule formation.

  2. Planetary Embryo Bow Shocks as a Mechanism for Chondrule Formation

    Science.gov (United States)

    Mann, Christopher R.; Boley, Aaron C.; Morris, Melissa A.

    2016-02-01

    We use radiation hydrodynamics with direct particle integration to explore the feasibility of chondrule formation in planetary embryo bow shocks. The calculations presented here are used to explore the consequences of a Mars-size planetary embryo traveling on a moderately excited orbit through the dusty, early environment of the solar system. The embryo’s eccentric orbit produces a range of supersonic relative velocities between the embryo and the circularly orbiting gas and dust, prompting the formation of bow shocks. Temporary atmospheres around these embryos, which can be created via volatile outgassing and gas capture from the surrounding nebula, can non-trivially affect thermal profiles of solids entering the shock. We explore the thermal environment of solids that traverse the bow shock at different impact radii, the effects that planetoid atmospheres have on shock morphologies, and the stripping efficiency of planetoidal atmospheres in the presence of high relative winds. Simulations are run using adiabatic and radiative conditions, with multiple treatments for the local opacities. Shock speeds of 5, 6, and 7 km s-1 are explored. We find that a high-mass atmosphere and inefficient radiative conditions can produce peak temperatures and cooling rates that are consistent with the constraints set by chondrule furnace studies. For most conditions, the derived cooling rates are potentially too high to be consistent with chondrule formation.

  3. Mountaineering Tourism

    Directory of Open Access Journals (Sweden)

    Patrick Maher

    2016-08-01

    Full Text Available Reviewed: Mountaineering Tourism Edited by Ghazali Musa, James Higham, and Anna Thompson-Carr. Abingdon, United Kingdom: Routledge, 2015. xxvi + 358 pp. Hardcover. US$ 145.00. ISBN 978-1-138-78237-2.

  4. Postglacial palaeoenvironments of the upper Bow Valley, Banff National Park, Alberta, Canada

    Science.gov (United States)

    Reasoner, Mel A.; Huber, Ulrike M.

    1999-03-01

    Crowfoot Lake sediments provide a sensitive 11,300 14C year record of glacial activity and vegetation change in the central Canadian Rocky Mountains. Bow Valley ice had receded from the Crowfoot Lake basin shortly before ca. 11,330 14C yr BP. Inorganic sediments associated with an expansion of alpine glaciers (Crowfoot Advance) were deposited in the basin during the Younger Dryas Chron. Prior to ca. 10,100 14C yr BP, the local vegetation was a sparse shrub-herb community dominated by Artemisia and Poaceae. Dramatic changes in the palaeobotanical record concomitant with the abrupt onset of organic sedimentation reflect the establishment of an open Pinus-dominated forest at ca. 10,100 14C yr BP. Fires may have accentuated the effects of climate in maintaining an open forest between ca. 9000 and 4160 14C yr BP. After ca. 4160 14C yr BP, Picea and Abies were dominant components of the local closed forest and subordinate xerophytic taxa were in decline. The consistent presence of mesophytic taxa after ca. 4160 14C yr BP indicate increases in precipitation associated with the onset of Neoglacial conditions. Sharp declines in local arboreal taxa occurred at ca. 900 14C yr BP along with increases in several taxa common to modern alpine tundra and subalpine meadows. These changes probably reflect expansions of valley floor meadows and descending alpine timberline in the drainage and are coincident with renewed glaciogenic sedimentation in the basin.

  5. Numerical Study on the Effect of Buffer Bow Structure in Ship-to-ship Collisions

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2005-01-01

    structure in ship-ship collisions as compared with that of standard bulbous bows. This is demonstrated by conducting a series of large-scale finite element analyses. The finite element analyses are conducted with the general-purpose nonlinear structural code “LS-DYNA”. The applied scenario is one where......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

  6. Interaction between an interplanetary magnetic cloud and the Earth's magnetosphere: Motions of the bow shock

    Science.gov (United States)

    Wu, D. J.; Chao, J. K.; Lepping, R. P.

    2000-06-01

    An interplanetary magnetic cloud (IMC) is an important solar-terrestrial connection event. It is an ideal object for the study of solar-terrestrial relations and space weather because the Earth's space environment can be affected considerably during an IMC passage. An IMC was observed to pass the Earth during October 18-20, 1995. Wind recorded its interplanetary characteristics at ~175RE upstream of the Earth's bow shock, and ~45 min later, Geotail, being near the nominal location of the dawn bow shock, detected IMC-related multiple bow shock crossings. Using simultaneous measurements from Wind and Geotail, we analyzed, with a semiempirical bow shock model with two parameters, the bow shock motion caused by the interaction of the IMC with the magnetosphere during the passage. We also compared the bow shock motion predicted by the model, and hence the predicted Geotail bow shock crossings, with Geotail observations of the actual crossings. The results showed that the observed multiple bow shock crossings, which were obviously due to temporal variations of the upstream solar wind, can be well explained by the model-predicted bow shock motion.

  7. Tibial bowing in children - what is normal? A radiographic study

    Energy Technology Data Exchange (ETDEWEB)

    Zbinden, Isabella [University of Basel, Department of Radiology, Basel (Switzerland); Rutz, Erich [University Children' s Hospital, Department of Orthopedic Surgery, Basel (Switzerland); Jacobson, Jon A. [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Magerkurth, Olaf [University Children' s Hospital, Department of Radiology, Basel (Switzerland); Kantonsspital Baden, Department of Radiology, Baden (Switzerland)

    2015-12-15

    To define osseous landmarks on tibia radiographs in order to establish age-related normal values characterizing physiological tibial bowing in children. Five hundred and twenty-six patients aged 0-17 years with normal radiographs of the lower legs were identified and retrospectively reviewed by two blinded radiologists. In anteroposterior (ap)/lateral (lat)-views, 3 lines defined tibial length and angulation. Line-A connecting proximal to distal corner of tibial metaphysic, lines B and C corresponding to corners of tibial metaphysis. Angle A/B defines proximal, A/C distal tibial-angulation. Tibial curvature is defined by distance of line-D parallel to A and tangential to tibial cortex. Normal values were calculated with linear-regression. Intra-/Interreader agreement were tested with a Bland-Altman-plot. Intrareader-agreement: Reader 1 showed a bias of -0.1, standard-deviation of bias was 1.9 and 95 %-limits-of-agreement -3.9- 3.7. Reader 2: -0.01, 2.4 and -4.7- 4.7. Interreader: 0.2, 1.6 and -2.9- 3.3. Angle-A/B ap was 80-100 , increasing with age (86.5-88); angle-AC ap was 82-107 (96.8-90.5), angle-AB lat was 81-107 (93.0-98.0); angle-AC lat was 76-102 (89.5-86.5); depth of curve ap was 0-11 % (8-3.5) and lat 2-13 %, (8.5-3.5). Age dependent tibial bowing can be assessed with this new measurement system and age-related normal-values characterizing physiological tibial bowing in children is established. (orig.)

  8. Modeling of the Archery Bow and Arrow Vibrations

    Directory of Open Access Journals (Sweden)

    I. Zaniewski

    2009-01-01

    Full Text Available Vibration processes in the compound and open kinematical chain with an external link, as a model of an archery bow and arrow system, are evaluated. A mechanical and mathematical model of bend oscillations of the system during accelerate motion of the external link is proposed. Correlation between longitudinal acceleration and natural frequencies is obtained. There are recommendations regarding determination of virtual forms to study arrow vibrations and buckling. The models and methods have been adapted for realization into the engineering method using well-known mathematical software packages.

  9. Properties of bow-shock sources at the Galactic center

    Science.gov (United States)

    Sanchez-Bermudez, J.; Schödel, R.; Alberdi, A.; Muzić, K.; Hummel, C. A.; Pott, J.-U.

    2014-07-01

    Context. There exists an enigmatic population of massive stars around the Galactic center (GC) that were formed some Myr ago. A fraction of these stars has been found to orbit the supermassive black hole, Sgr A*, in a projected clockwise disk-like structure, which suggests that they were formed in a formerly existing dense disk around Sgr A*. Aims: We focus on a subgroup of objects, the extended, near-infrared (NIR) bright sources IRS 1W, IRS 5, IRS 10W, and IRS 21, that have been suggested to be young, massive stars that form bow shocks through their interaction with the interstellar medium (ISM). Their nature has impeded accurate determinations of their orbital parameters. We aim at establishing their nature and kinematics to test whether they form part of the clockwise disk. Methods: We performed NIR multiwavelength imaging with NACO/VLT using direct adaptive optics (AO) and AO-assisted sparse aperture masking (SAM). We introduce a new method for self-calibration of the SAM point spread function in dense stellar fields. The emission mechanism, morphology, and kinematics of the targets were examined via 3D models, combined with existing models of the gas flow in the central parsec. Results: We confirm previous findings that IRS 21, IRS 1W, and IRS 5 are bow-shocks created by the interaction between mass-losing stars and the interstellar gas. The nature of IRS 10W remains unclear. Our modeling shows that the bow-shock emission is caused by thermal emission, while the scattering of stellar light does not play a significant role. IRS 1W shows a morphology that is consistent with a bow shock produced by an anisotropic stellar wind or by locally inhomogeneous ISM density. Our best-fit models provide estimates of the local proper motion of the ISM in the Northern Arm that agree with previously published models that were based on radio interferometry and NIR spectroscopy. Assuming that all of the sources are gravitationally tied to Sagittarius A*, their orbital planes

  10. Power aspects of processes in the bow shock region

    Science.gov (United States)

    Sedykh, Pavel

    Bow shock is a powerful transformer of the solar wind kinetic energy into the gas dynamic and electromagnetic energy. The solar wind energy also feeds the ion acceleration process, the generation of waves in the region of bow shock, and the energy necessary to build up the foreshock. A jump of the magnetic field tangential component at front crossing means that the front carries an electric current. The solar wind kinetic energy partly transforms to gas kinetic and electromagnetic energy during its passage through the bow shock front. The transition layer (magnetosheath) can use part of this energy for accelerating of plasma, but can conversely spend part its kinetic energy on the electric power generation, which afterwards may be used by the magnetosphere. Thereby, transition layer can be both consumer (sink) and generator (source) of electric power depending upon special conditions. The direction of the current behind the bow shock front depends on the sign of the IMF B _{z}-component. It is this electric current which sets convection of plasma in motion. The process of current penetration into the magnetosphere is two-step. First, a polarization field is formed that penetrates layer-by-layer into the magnetosphere. More exactly, a pulse corresponding to this field penetrates into the plasma. Then, if the system is inhomogeneous, the flow may redistribute the pressure so that gradients appearing in the plasma induce an electric current. In power terms, this electric current is required to maintain convection in the inhomogeneous system. Any change in the external current through the magnetosphere causes a convection restructuring within a time on the order of travel time of the magnetosonic wave from the magnetopause to the center of the system, because the restructuring wave comes from both flanks. Using the expressions obtained in this paper for normal components of the electric current, the flow of matter brought into the magnetosphere can be estimated. A

  11. Mercury's magnetopause and bow shock from MESSENGER observations

    Science.gov (United States)

    Winslow, R. M.; Anderson, B. J.; Johnson, C. L.; Slavin, J. A.; Korth, H.; Purucker, M. E.; Baker, D. N.; Solomon, S. C.

    2012-12-01

    We establish the time-averaged shape and location of Mercury's magnetopause and bow shock from orbital observations by the MESSENGER Magnetometer. We fit empirical models to the midpoints of boundary crossings as well as to probability density maps of the magnetopause and bow shock positions. The magnetopause is fit by two different surfaces: (1) a paraboloid, and (2) a surface for which the position R from the planetary dipole varies as [1+cos(θ)]-α, where θ is the angle between R and the dipole-Sun line, and α is a flaring parameter that governs whether the magnetotail is closed (α fit simultaneously both the dayside and nightside magnetopause crossings, but the second surface gives the best-fit overall shape to the observations with a subsolar stand-off distance, Rss, of 1.45 RM (where RM is Mercury's radius), and a flaring parameter α = 0.5. The average magnetopause shape and location were determined under a mean solar wind ram pressure, PRam, of 14.3 nPa. The best-fit bow shock shape established under an average Alfvén Mach number (MA ) of 6.6 is described by a hyperboloid having Rss = 1.96 RM and an eccentricity of 1.02. These boundaries move as PRam and MA vary, but their shape remains unchanged. The magnetopause Rss varies from 1.55 RM to 1.35 RM for PRam in the range 8.8 to 21.6 nPa. The bow shock Rss varies from 2.29 RM to 1.89 RM for MA in the range 4.12 to 11.8. To first order, the boundaries are well approximated by figures of revolution. Additional effects of the interplanetary magnetic field are masked by the large dynamic variability of these boundaries. Despite the moderate average magnetic shear conditions at Mercury, the magnetotail surface is nearly cylindrical, with a radius of ~2.7 RM at a distance 3 RM downstream of Mercury. By comparison, Earth's magnetotail flaring continues until a downstream distance of ~10 Rss. This result may indicate that reconnection in Mercury's magnetotail does not take place beyond ~3 RM downstream of the

  12. Successful Female Mountaineers

    Institute of Scientific and Technical Information of China (English)

    TANSIYIN

    2004-01-01

    The Third Mountaineering Meet took place from September 26 to October 8, 2003. It was sponsored by the Tibet Association for Mountaineers and undertaken by the Tibet Mountaineering Team and the Tibet Mountaineering School.

  13. Quasilinear simulations of interplanetary shocks and Earth's bow shock

    Science.gov (United States)

    Afanasiev, Alexandr; Battarbee, Markus; Ganse, Urs; Vainio, Rami; Palmroth, Minna; Pfau-Kempf, Yann; Hoilijoki, Sanni; von Alfthan, Sebastian

    2016-04-01

    We have developed a new self-consistent Monte Carlo simulation model for particle acceleration in shocks. The model includes a prescribed large-scale magnetic field and plasma density, temperature and velocity profiles and a self-consistently computed incompressible ULF foreshock under the quasilinear approximation. Unlike previous analytical treatments, our model is time dependent and takes full account of the anisotropic particle distributions and scattering in the wave-particle interaction process. We apply the model to the problem of particle acceleration at traveling interplanetary (IP) shocks and Earth's bow shock and compare the results with hybrid-Vlasov simulations and spacecraft observations. A qualitative agreement in terms of spectral shape of the magnetic fluctuations and the polarization of the unstable mode is found between the models and the observations. We will quantify the differences of the models and explore the region of validity of the quasilinear approach in terms of shock parameters. We will also compare the modeled IP shocks and the bow shock, identifying the similarities and differences in the spectrum of accelerated particles and waves in these scenarios. The work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA). The Academy of Finland is thanked for financial support. We acknowledge the computational resources provided by CSC - IT Centre for Science Ltd., Espoo.

  14. Design and Analysis of the First BOWS Contest

    Directory of Open Access Journals (Sweden)

    Barni M

    2007-01-01

    Full Text Available The break our watermarking system (BOWS contest was launched in the framework of the activities carried out by the European Network of Excellence for Cryptology ECRYPT. The aim of the contest was to investigate how and when an image watermarking system can be broken while preserving the highest possible quality of the content, in the case the watermarking system is subject to a massive worldwide attack. The great number of participants and the echo that the contest has had in the watermarking community contributed to make BOWS a great success. From a scientific point of view, many insights into the problems attackers have to face with when operating in a practical scenario have been obtained, confirming the threat posed by the sensitivity attack, which turned out to be the most successful attack. At the same time, several interesting modifications of such an attack have been proposed to make it work in a real scenario under limited communication and time resources. This paper describes how the contest has been designed and analyzes the general progress of the attacks during the contest.

  15. Lunar Surface Potential Increases during Terrestrial Bow Shock Traversals

    Science.gov (United States)

    Collier, Michael R.; Stubbs, Timothy J.; Hills, H. Kent; Halekas, Jasper; Farrell, William M.; Delory, Greg T.; Espley, Jared; Freeman, John W.; Vondrak, Richard R.; Kasper, Justin

    2009-01-01

    Since the Apollo era the electric potential of the Moon has been a subject of interest and debate. Deployed by three Apollo missions, Apollo 12, Apollo 14 and Apollo 15, the Suprathermal Ion Detector Experiment (SIDE) determined the sunlit lunar surface potential to be about +10 Volts using the energy spectra of lunar ionospheric thermal ions accelerated toward the Moon. We present an analysis of Apollo 14 SIDE "resonance" events that indicate the lunar surface potential increases when the Moon traverses the dawn bow shock. By analyzing Wind spacecraft crossings of the terrestrial bow shock at approximately this location and employing current balancing models of the lunar surface, we suggest causes for the increasing potential. Determining the origin of this phenomenon will improve our ability to predict the lunar surface potential in support of human exploration as well as provide models for the behavior of other airless bodies when they traverse similar features such as interplanetary shocks, both of which are goals of the NASA Lunar Science Institute's Dynamic Response of the Environment At the Moon (DREAM) team.

  16. Smashing the Guitar: An Evolving Neutron Star Bow Shock

    CERN Document Server

    Chatterjee, S

    2003-01-01

    The Guitar nebula is a spectacular example of an H-alpha bow shock nebula produced by the interaction of a neutron star with its environment. The radio pulsar B2224+65 is traveling at ~800--1600 km/s (for a distance of 1--2 kpc), placing it on the high-velocity tail of the pulsar velocity distribution. Here we report time evolution in the shape of the Guitar nebula, the first such observations for a bow shock nebula, as seen in H-alpha imaging with the Hubble Space Telescope. The morphology of the nebula provides no evidence for anisotropy in the pulsar wind, nor for fluctuations in the pulsar wind luminosity. The nebula shows morphological changes over two epochs spaced by seven years that imply the existence of significant gradients and inhomogeneities in the ambient interstellar medium. These observations offer astrophysically unique, in situ probes of length scales between 5E-4 pc and 0.012 pc. Model fitting suggests that the nebula axis -- and thus the three-dimensional velocity vector -- lies within 20 ...

  17. Far-UV bow shock nebula around PSR J0437-4715

    CERN Document Server

    Rangelov, Blagoy; Kargaltsev, Oleg; Durant, Martin; Bykov, Andrei M; Krassilchtchikov, Alexandre

    2016-01-01

    Pulsars traveling at supersonic speeds are often accompanied by cometary bow shocks seen in Halpha. We report on the first detection of a pulsar bow shock in the far-ultraviolet (FUV). We detected it in FUV images of the nearest millisecond pulsar J0437-4715 obtained with the Hubble Space Telescope. The images reveal a bow-like structure positionally coincident with part of the previously detected Halpha bow shock, with an apex at 10'' ahead of the moving pulsar. Its FUV luminosity, L(1250-2000 A) ~ 5x10^28 erg/s, exceeds the Halpha luminosity from the same area by a factor of 10. The FUV emission could be produced by the shocked ISM matter or, less likely, by relativistic pulsar wind electrons confined by strong magnetic field fluctuations in the bow shock. In addition, in the FUV images we found a puzzling extended (~3'' in size) structure overlapping with the limb of the bow shock. If related to the bow shock, it could be produced by an inhomogeneity in the ambient medium or an instability in the bow shock...

  18. The bowing potential of granitic rocks: rock fabrics, thermal properties and residual strain

    Science.gov (United States)

    Siegesmund, S.; Mosch, S.; Scheffzük, Ch.; Nikolayev, D. I.

    2008-10-01

    The bowing of natural stone panels is especially known for marble slabs. The bowing of granite is mainly known from tombstones in subtropical humid climate. Field inspections in combination with laboratory investigations with respect to the thermal expansion and the bowing potential was performed on two different granitoids (Cezlak granodiorite and Flossenbürg granite) which differ in the composition and rock fabrics. In addition, to describe and explain the effect of bowing of granitoid facade panels, neutron time-of-flight diffraction was applied to determine residual macro- and microstrain. The measurements were combined with investigations of the crystallographic preferred orientation of quartz and biotite. Both samples show a significant bowing as a function of panel thickness and destination temperature. In comparison to marbles the effect of bowing is more pronounced in granitoids at temperatures of 120°C. The bowing as well as the thermal expansion of the Cezlak sample is also anisotropic with respect to the rock fabrics. A quantitative estimate was performed based on the observed textures. The effect of the locked-in stresses may also have a control on the bowing together with the thermal stresses related to the different volume expansion of the rock-forming minerals.

  19. Changbai Mountains

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    The Changbai Mountains are located within the boundaries of Antu County, Fusong County and Changbai County of Jilin City of Jilin Province. They cover a total area of more than 200,000 hectares and is one of the largest nature preserves in China. There are abundant species of living things, such as Dongbei Tiger, sika, sable and

  20. Mountain medicin

    DEFF Research Database (Denmark)

    Bay, Bjørn; Hjuler, Kasper Fjellhaugen

    2016-01-01

    Travelling to high altitudes is an increasingly popular form of recreational holiday. Individual medical advice may be essential for certain groups of individuals such as patients with chronic disorders, pregnant women or children. This is the second part in a series of two articles on mountain...

  1. Southeastern Coastal Plain aquifer system

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the extent of the Southeastern Coastal Plain aquifer system in Kentucky, Tennessee, Mississippi, Alabama, Georgia, and South Carolina.

  2. Bow Shock Leads the Way for a Speeding Hot Jupiter

    Science.gov (United States)

    Kohler, Susanna

    2015-09-01

    As hot Jupiters whip around their host stars, their speeds can exceed the speed of sound in the surrounding material, theoretically causing a shock to form ahead of them. Now, a study has reported the detection of such a shock ahead of transiting exoplanet HD 189733b, providing a potential indicator of the remarkably strong magnetic field of the planet.Rushing PlanetsDue to their proximity to their hosts, hot Jupiters move very quickly through the stellar wind and corona surrounding the star. When this motion is supersonic, the material ahead of the planet can be compressed by a bow shock and for a transiting hot Jupiter, this shock will cross the face of the host star in advance of the planets transit.In a recent study, a team of researchers by Wilson Cauley of Wesleyan University report evidence of just such a pre-transit. The teams target is exoplanet HD 189733b, one of the closest hot Jupiters to our solar system. When the authors examined high-resolution transmission spectra of this system, they found that prior to the optical transit of the planet, there was a large dip in the transmission of the first three hydrogen Balmer lines. This could well be the absorption of an optically-thick bow shock as it moves past the face of the star.Tremendous MagnetismOperating under this assumption, the authors create a model of the absorption expected from a hot Jupiter transiting with a bow shock ahead of it. Using this model, they show that a shock leading the planet at a distance of 12.75 times the planets radius reproduces the key features of the transmission spectrum.This stand-off distance is surprisingly large. Assuming that the location of the bow shock is set by the point where the planets magnetospheric pressure balances the pressure of the stellar wind or corona that it passes through, the planetary magnetic field would have to be at least 28 Gauss. This is seven times the strength of Jupiters magnetic field!Understanding the magnetic fields of exoplanets is

  3. Simulation of the oscillation regimes of bowed bars: a non-linear modal approach

    Science.gov (United States)

    Inácio, Octávio; Henrique, Luís.; Antunes, José

    2003-06-01

    It is still a challenge to properly simulate the complex stick-slip behavior of multi-degree-of-freedom systems. In the present paper we investigate the self-excited non-linear responses of bowed bars, using a time-domain modal approach, coupled with an explicit model for the frictional forces, which is able to emulate stick-slip behavior. This computational approach can provide very detailed simulations and is well suited to deal with systems presenting a dispersive behavior. The effects of the bar supporting fixture are included in the model, as well as a velocity-dependent friction coefficient. We present the results of numerical simulations, for representative ranges of the bowing velocity and normal force. Computations have been performed for constant-section aluminum bars, as well as for real vibraphone bars, which display a central undercutting, intended to help tuning the first modes. Our results show limiting values for the normal force FN and bowing velocity ẏbow for which the "musical" self-sustained solutions exist. Beyond this "playability space", double period and even chaotic regimes were found for specific ranges of the input parameters FN and ẏbow. As also displayed by bowed strings, the vibration amplitudes of bowed bars also increase with the bow velocity. However, in contrast to string instruments, bowed bars "slip" during most of the motion cycle. Another important difference is that, in bowed bars, the self-excited motions are dominated by the system's first mode. Our numerical results are qualitatively supported by preliminary experimental results.

  4. The bowed catheter sign: a risk for pericardial tamponade

    Energy Technology Data Exchange (ETDEWEB)

    Towbin, Richard [Phoenix Children' s Hospital, Department of Radiology, Phoenix, AZ (United States)

    2008-03-15

    The use of a central venous catheter (CVC) has become commonplace in the care of children with a wide variety of medical and surgical problems. Complications resulting from the insertion of these catheters are well recognized and can be life-threatening. When a temporary CVC or other catheter is inserted into the central venous system it is secured to the skin with a combination of sutures and sterile dressing. This fixes the catheter in place and does not allow it to retract, thereby putting pressure on the right atrial wall via the catheter tip if it is too long. The probability of wall penetration is increased if a catheter or device is tapered at the point of contact. The purpose of this case report is to present the bowed catheter sign and to review the anatomy of the cavotricuspid isthmus, a possible predisposing factor to cardiac perforation and tamponade. (orig.)

  5. Violin Pedagogy and the Physics of the Bowed String

    Science.gov (United States)

    McLeod, Alexander Rhodes

    The paper describes the mechanics of violin tone production using non-specialist language, in order to present a scientific understanding of tone production accessible to a broad readership. As well as offering an objective understanding of tone production, this model provides a powerful tool for analyzing the technique of string playing. The interaction between the bow and the string is quite complex. Literature reviewed for this study reveals that scientific investigations have provided important insights into the mechanics of string playing, offering explanations for factors which both contribute to and limit the range of tone colours and dynamics that stringed instruments can produce. Also examined in the literature review are significant works of twentieth century violin pedagogy exploring tone production on the violin, based on the practical experience of generations of teachers and performers. Hermann von Helmholtz described the stick-slip cycle which drives the string in 1863, which replaced earlier ideas about the vibration of violin strings. Later, scientists such as John Schelleng and Lothar Cremer were able to demonstrate how the mechanics of the bow-string interaction can create different tone colours. Recent research by Anders Askenfelt, Knut Guettler, and Erwin Schoonderwaldt have continued to refine earlier research in this area. The writings of Lucien Capet, Leopold Auer, Carl Flesch, Paul Rolland, Kato Havas, Ivan Galamian, and Simon Fischer are examined and analyzed. Each author describes a different approach to tone production on the violin, representing a different understanding of the underlying mechanism. Analyzing these writings within the context of a scientific understanding of tone production makes it possible to compare these approaches more consistently, and to synthesize different concepts drawn from the diverse sources evaluated.

  6. Bowing of marble panels: On-site damage analysis from the oeconomicum building at Goettingen (Germany)

    Science.gov (United States)

    Koch, A.; Siegesmund, S.

    2003-04-01

    The use of natural stone panels or cladding material for building facades has led to some durability problems, especially with marble slabs. To examine the effects of intrinsic and extrinsic parameters on bowing a very detailed study was performed on the Oeconomicum Building at the University of Goettingen. In total 1556 panels from the whole building were measured with respect to the bowing using a bow-meter. The variation of bowing ranges from concave (up to 23 mm/m) to convex (up to -11 mm/m). The variation is not controlled by the position with respect to the geographical coordinates, height above ground, shadows, temperature etc.. On the north facade the different rock structures visible on the panel surfaces are a result of the marble slabs being cut in different directions. The different degree in bowing is associated with the structure of the marble since all other influencing factors are relatively constant (position, temperature, moisture content, building physics). Experimental data on the expansion behaviour under dry and/or wet conditions reveal a different degree in bowing with respect to the rock fabric and may help to explain the observed differences in bowing. The effect of the rock fabric especially of the lattice preferred orientation in this case clearly controls the deterioration of the marble and the degree of bowing. The bowing is also characterized by an increase in the porosity, decreasing values of ultrasonic wave velocities and flexural strength. The loss of cohesion in the strongly deteriorated panels is clearly visible in the microstructure by the open grain boundaries which are interconnected to intergranular microcracks.

  7. Geologic Map of the Atlin Quadrangle, Southeastern Alaska

    Science.gov (United States)

    Brew, David A.; Himmelberg, Glen R.; Ford, Arthur B.

    2009-01-01

    This map presents the results of U.S. Geological Survey (USGS) geologic bedrock mapping studies in the mostly glacier covered Atlin 1:250,000-scale quadrangle, northern southeastern Alaska. These studies are part of a long-term systematic effort by the USGS to provide bedrock geologic and mineral-resource information for all of southeastern Alaska, covering all of the Tongass National Forest (including Wilderness Areas) and Glacier Bay National Park and Preserve. Some contributions to this effort are those concerned with southwesternmost part of the region, the Craig and Dixon Entrance quadrangles (Brew, 1994; 1996) and with the Wrangell-Petersburg area (Brew, 1997a-m; Brew and Grybeck, 1997; Brew and Koch, 1997). As shown on the index map (fig. 1), the study area is almost entirely in the northern Coast Mountains adjacent to British Columbia, Canada. No previous geologic map has been published for the area, although Brew and Ford (1985) included a small part of it in a preliminary compilation of the adjoining Juneau quadrangle; and Brew and others (1991a) showed the geology at 1:500,000 scale. Areas mapped nearby in British Columbia and the United States are also shown on figure 1. All of the map area is in the Coast Mountains Complex as defined by Brew and others (1995a). A comprehensive bibliography is available for this and adjacent areas (Brew, 1997n).

  8. Rocky Mountain Spotted Fever

    Science.gov (United States)

    ... facebook share with twitter share with linkedin Rocky Mountain Spotted Fever Rocky Mountain spotted fever is a ... New Mexico. Why Is the Study of Rocky Mountain Spotted Fever a Priority for NIAID? Tickborne diseases ...

  9. Land changes and their driving forces in the Southeastern United States

    Science.gov (United States)

    Napton, D.E.; Auch, R.F.; Headley, R.; Taylor, J.L.

    2010-01-01

    The ecoregions of the Middle Atlantic Coastal Plain, Southeastern Plains, Piedmont, and Blue Ridge provide a continuum of land cover from the Atlantic Ocean to the highest mountains in the East. From 1973 to 2000, each ecoregion had a unique mosaic of land covers and land cover changes. The forests of the Blue Ridge Mountains provided amenity lands. The Piedmont forested area declined, while the developed area increased. The Southeastern Plains became a commercial forest region, and most agricultural lands that changed became forested. Forests in the Middle Atlantic Coastal Plain declined, and development related to recreation and retirement increased. The most important drivers of land conversion were associated with commercial forestry, competition between forest and agriculture, and economic and population growth. These and other drivers were modified by each ecoregion's unique suitability and land use legacies with the result that the same drivers often produced different land changes in different ecoregions. ?? Springer-Verlag 2009.

  10. Bow-tie topological features of metabolic networks and the functional significance

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jing; TAO Lin; YU Hong; LUO JianHua; GAO ZhiWei; LI YiXue

    2007-01-01

    Exploring the structural topology of genome-based large-scale metabolic network is essential for in vestigating possible relations between structure and functionality. Visualization would be helpful for obtaining immediate information about structural organization. In this work, metabolic networks of 75 organisms were investigated from a topological point of view. A spread bow-tie model was proposed to give a clear visualization of the bow-tie structure for metabolic networks. The revealed topological pattern helps to design more efficient algorithm specifically for metabolic networks. This coarsegrained graph also visualizes the vulnerable connections in the network, and thus could have important implication for disease studies and drug target identifications. In addition, analysis on the reciprocal links and main cores in the GSC part of bow-tie also reveals that the bow-tie structure of metabolic networks has its own intrinsic and significant features which are significantly different from those of random networks.

  11. The Effect of Buffer Bow Structures on Collision Damages of Oil Tankers

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Pedersen, Preben Terndrup; Friis-Hansen, Peter

    2007-01-01

    In order to investigate the effectiveness of buffer bow structures on prevention of oil spills in tanker collisions, probabilistic collision damage analyses were performed using a newly developed Simplified Ship Collision Analysis Tool (SSCAT). Monte Carlo Simulation (MCS) was carried out using...... the striking ships use conventional bulbous bows. The probability of oil spill from the VLCC, given a collision, is estimated and the risk reducing effect of introducing buffer bow structures is discussed....... SSCAT for collision scenarios where striking ships at various speeds, sizes and bulb shapes collide perpendicularly with a VLCC in fully loaded condition. The probability of oil spill from the struck VLCC in cases where all the striking ships use buffer bulbous bows was compared with the case where all...

  12. Oxygen foreshock of Mars and its implication on ion acceleration in the bow shock

    Science.gov (United States)

    Yamauchi, Masatoshi; Lundin, Rickard; Frahm, Rudy; Sauvaud, Jean-Andre; Holmstrom, Mats; Barabash, Stas

    2016-04-01

    Ion acceleration inside the bow shock is one of the poorly understood phenomena that has been observed for more than 30 years as the foreshock phenomena. While the Fermi-acceleration mechanism explains the diffuse component of foreshock ions, we still do not know the detailed mechanism that produces the discrete intense ions flowing along the local magnetic field direction (with and without gyration). One of the reasons for such difficulty is that majority of the bow shock study was performed for the Earth's case where Oxygen ions cannot be used to understand the acceleration mechanisms. The planetary oxygen ions that reach the Earth's bow shock have already been significantly accelerated, and are not adequate for such a study. In this sense the Martian bow shock is an ideal place to study the acceleration mechanisms leading to foreshock ions, although the nature of the bow shock is slightly different between the Earth and Mars (Yamauchi et al., 2011). On 21 September 2008, the Mars Express (MEX) Ion Mass Analyser (IMA) detected foreshock-like discrete distributions of oxygen ions at around 1 keV in the solar wind attached to the bow shock. This was the first time that a substantial amount of planetary oxygen was observed upstream of the bow shock. The oxygen energy increased from low energy (< 300 keV) inside the magnetosheath (or it should be called an extended bow shock) to nearly 2 keV at more than 2000 km from the bow shock. Foreshock-like protons are also observed but at a shifted location from the oxygen by about 1000 km, at a slightly higher energy, and flowing in a slightly different direction than the oxygen ions. Both protons and oxygen ions are flowing anti-sunward at different angles with respect to the solar wind direction. The observation is consistent with an electric potential barrier at the bow shock that simultaneously accelerates the planetary oxygen ions outward (to form the foreshock oxygen ions) and reflects a portion of the solar wind (to

  13. Defense Modernization Plans Through the 2020s: Addressing the Bow Wave

    Science.gov (United States)

    2016-04-30

    45 p.m. Chair: Andrew Hunter, Senior Fellow in the International Security Program, Director of Defense-Industrial Initiatives Group , Center for...and has appeared on CNBC, CNN, NPR, Al Jazeera English, and Fox News. He has been a guest lecturer for organizations and teaches a class on the...their peak years of funding requirements at roughly the same time in the 2020s, creating a modernization bow wave. Just as a large bow wave slows a ship

  14. On the observability of bow shocks of Galactic runaway OB stars

    Science.gov (United States)

    Meyer, D. M.-A.; van Marle, A.-J.; Kuiper, R.; Kley, W.

    2016-06-01

    Massive stars that have been ejected from their parent cluster and supersonically sailing away through the interstellar medium (ISM) are classified as exiled. They generate circumstellar bow-shock nebulae that can be observed. We present two-dimensional, axisymmetric hydrodynamical simulations of a representative sample of stellar wind bow shocks from Galactic OB stars in an ambient medium of densities ranging from nISM = 0.01 up to 10.0 cm- 3. Independently of their location in the Galaxy, we confirm that the infrared is the most appropriated waveband to search for bow shocks from massive stars. Their spectral energy distribution is the convenient tool to analyse them since their emission does not depend on the temporary effects which could affect unstable, thin-shelled bow shocks. Our numerical models of Galactic bow shocks generated by high-mass ( ≈ 40 M⊙) runaway stars yield H α fluxes which could be observed by facilities such as the SuperCOSMOS H-Alpha Survey. The brightest bow-shock nebulae are produced in the denser regions of the ISM. We predict that bow shocks in the field observed at H α by means of Rayleigh-sensitive facilities are formed around stars of initial mass larger than about 20 M⊙. Our models of bow shocks from OB stars have the emission maximum in the wavelength range 3 ≤ λ ≤ 50 μm which can be up to several orders of magnitude brighter than the runaway stars themselves, particularly for stars of initial mass larger than 20 M⊙.

  15. A hydrodynamic optimization design methodology for a ship bulbous bow under multiple operating conditions

    OpenAIRE

    Yu Lu; Xin Chang; An-kang Hu

    2016-01-01

    The main objective of this article is to describe an innovative methodology for the hydrodynamic optimization of a ship bulbous bow which considers multiple operating conditions. The proposed method is more practical and effective than the traditional optimization process, which is only based on contractually specified design condition. Parametric form approaches are adopted by employing an F-spline curve in order to generate variants of the hull bulbous bow forms using form design parameters...

  16. Clause Types in Southeastern Tepehuan.

    Science.gov (United States)

    Willett, Thomas L.

    The clause in Southeastern Tepehuan consists of a predicate, its associated arguments, and other modifying elements. This paper seeks to show the various types of semantic and surface clauses and the relation between them. The semantic clause consists of various semantic components, both nuclear and peripheral, semantic prosodies, and certain…

  17. Sentence Components in Southeastern Tepehuan.

    Science.gov (United States)

    Willett, Thomas L.

    This paper explores the intra-clausal relations of minimal locutionary and illocutionary force in Southeastern Tepehuan. It surveys the semantic and syntactic sentence types with primary reference to grammatical relations. The semantic propositional structures, along with their modal parameters and other semantic prosodies are discussed in Section…

  18. Suicide in Batman, Southeastern Turkey

    Science.gov (United States)

    Altindag, Abdurrahman; Ozkan, Mustafa; Oto, Remzi

    2005-01-01

    The southeastern part of Turkey has comparatively high female suicide rates. We aimed to research social, economic, cultural, and psychiatric reasons of suicides in Batman in a case-controlled psychological autopsy study comparing suicides with matched community controls. The female suicide rate was 9.3 per 100.000 and the female/male ratio was…

  19. Observations of Bow Shocks of Runaway Stars with H.E.S.S

    CERN Document Server

    Schulz, A; Klepser, S

    2016-01-01

    Runaway stars form bow shocks by sweeping up interstellar matter in their direction of motion. Theoretical models predict a spectrally wide non-thermal component reaching up to gamma-ray energies at a flux level detectable with current instruments. They were motivated by a detection of non-thermal radio emission from the bow shock of BD$+43^\\circ3654$ and a possible detection of non-thermal X-rays from AE Aurigae. A search in the high-energy regime using data from \\textit{Fermi}-LAT resulted in flux upper limits for 27 candidates listed in the first E-BOSS catalogue. We perform the first systematic search for TeV emission from bow shocks of runaway stars. Using all available archival H.E.S.S. I data we search for very-high-energy gamma-ray emission at the positions of bow shock candidates listed in the second E-BOSS catalogue. This catalogue comprises 73 bow shock candidates, 32 of which have been observed with the H.E.S.S. telescopes. None of the observed bow shock candidates shows significant emission in th...

  20. On the observability of bow shocks of Galactic runaway OB stars

    CERN Document Server

    Meyer, D M -A; Kuiper, R; Kley, W

    2016-01-01

    Massive stars that have been ejected from their parent cluster and supersonically sailing away through the interstellar medium (ISM) are classified as exiled. They generate circumstellar bow shock nebulae that can be observed. We present two-dimensional, axisymmetric hydrodynamical simulations of a representative sample of stellar wind bow shocks from Galactic OB stars in an ambient medium of densities ranging from n_ISM=0.01 up to 10.0/cm3. Independently of their location in the Galaxy, we confirm that the infrared is the most appropriated waveband to search for bow shocks from massive stars. Their spectral energy distribution is the convenient tool to analyze them since their emission does not depend on the temporary effects which could affect unstable, thin-shelled bow shocks. Our numerical models of Galactic bow shocks generated by high-mass (~40 Mo) runaway stars yield H$\\alpha$ fluxes which could be observed by facilities such as the SuperCOSMOS H-Alpha Survey. The brightest bow shock nebulae are produc...

  1. PENGARUH ANTI-SLAMMING BULBOUS BOW TERHADAP GERAKAN SLAMMING PADA KAPAL PERINTIS 200 DWT

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2016-02-01

    Full Text Available Analisis seakeeping (kemampuan olah gerak kapal merupakan aspek penting dalam perancangan kapal. Berdasarkan analisis tersebut, dapat diketahui batas operasional dari sebuah kapal. Salah satunya adalah dapat mengetahui kemampuan kapal pada tinggi gelombang signifikan (Hs tertentu. Memodifikasi bentuk haluan kapal dengan membuat dasar dari haluan tersebut lebih rendah dibandingkan dengan dasar lambung kapal nya (dibawah garis baseline kapal dinamakan Anti-Slamming Bow. Pada penelitian ini, anti-slamming bow ditambahkan dengan ­bulbous bow yang dinamakan dengn Anti-Slamming Bulbous Bow (ASB. Panjang (lasb dan tinggi (hasb Anti-Slamming Bulbous Bow divariasikan untuk mendapatkan probabilitas dan intensitas slamming yang paling rendah. Metode untuk menghitung RAO menggunakan Metode Panel. Hasil penelitian menunjukkan bahwa nilai probabilitas pada kapal existing (model awal pada Hs = 4 m dan Tave = 5 s pada kecepatan 14 knot tidak memenuhi standar kriteria Nordforsk ’87 karena memiliki nilai probabilitas slamming sebesar 12,19%. Selain model awal, model 1, model 3 dan model 5 juga tidak memenuhi standar kriteria karena memiliki nilai probabilitas slamming sebesar 5,19%, 5,04% dan 5,10%. Parameter ukuran anti-slamming bulbous bow terbaik terdapat pada model 6 dimana rasio panjang ASB terhadap Lpp kapal sebesar 0,4 dan rasio tinggi ASB terhadap sarat kapal sebesar 0,4. Sedangkan bentuk Bulbous terbaik adalah Bulbous A yaitu bulbous tipe bentuk titik air tergantung. Model ini memiliki nilai  probabilas sebesar 1,95% dan memenuhi kriteria Nordforsk ’87.

  2. Effect of bow-type initial imperfection on reliability of minimum-weight, stiffened structural panels

    Science.gov (United States)

    Stroud, W. Jefferson; Krishnamurthy, Thiagaraja; Sykes, Nancy P.; Elishakoff, Isaac

    1993-01-01

    Computations were performed to determine the effect of an overall bow-type imperfection on the reliability of structural panels under combined compression and shear loadings. A panel's reliability is the probability that it will perform the intended function - in this case, carry a given load without buckling or exceeding in-plane strain allowables. For a panel loaded in compression, a small initial bow can cause large bending stresses that reduce both the buckling load and the load at which strain allowables are exceeded; hence, the bow reduces the reliability of the panel. In this report, analytical studies on two stiffened panels quantified that effect. The bow is in the shape of a half-sine wave along the length of the panel. The size e of the bow at panel midlength is taken to be the single random variable. Several probability density distributions for e are examined to determine the sensitivity of the reliability to details of the bow statistics. In addition, the effects of quality control are explored with truncated distributions.

  3. Flow performance of highly loaded axial fan with bowed rotor blades

    Science.gov (United States)

    Chen, L.; Liu, X. J.; Yang, A. L.; Dai, R.

    2013-12-01

    In this paper, a partial bowed rotor blade was proposed for a newly designed high loaded axial fan. The blade was positively bowed 30 degrees from hub to 30 percent spanwise position. Flows of radial blade and bowed blade fans were numerically compared for various operation conditions. Results show that the fan's performance is improved. At the designed condition with flow coefficient of 0.52, the efficiency of the bowed blade fan is increased 1.44% and the static pressure rise is increased 11%. Comparing the flow structures, it can be found that the separated flow in the bowed fan is reduced and confined within 20 percent span, which is less than the 35 percent in the radial fan. It means that the bowed blade generates negative blade force and counteracts partial centrifugal force. It is alleviates the radial movements of boundary layers in fan's hub region. Flow losses due to 3D mixing are reduced in the rotor. Inlet flow to downstream stator is also improved.

  4. Bow-shock pulsar-wind nebulae passing through density discontinuities

    Science.gov (United States)

    Yoon, Doosoo; Heinz, Sebastian

    2017-01-01

    Bow-shock pulsar-wind nebulae are a subset of pulsar-wind nebulae that form when the pulsar has high velocity due to the natal kick during the supernova explosion. The interaction between the relativistic wind from the fast-moving pulsar and the interstellar medium produces a bow-shock and a trail, which are detectable in Hα emission. Among such bow-shock pulsar-wind nebulae, the Guitar Nebula stands out for its peculiar morphology, which consists of a prominent bow-shock head and a series of bubbles further behind. We present a scenario in which multiple bubbles can be produced when the pulsar encounters a series of density discontinuities in the ISM. We tested the scenario using 2D and 3D hydrodynamic simulations. The shape of the Guitar Nebula can be reproduced if the pulsar traversed a region of declining low density. We also show that if a pulsar encounters an inclined density discontinuity, it produces an asymmetric bow-shock head, consistent with observations of the bow-shock of the millisecond pulsar J2124-3358.

  5. Global Explicit Particle-in-cell Simulations of the Nonstationary Bow Shock and Magnetosphere

    Science.gov (United States)

    Yang, Zhongwei; Huang, Can; Liu, Ying D.; Parks, George K.; Wang, Rui; Lu, Quanming; Hu, Huidong

    2016-07-01

    We carry out two-dimensional global particle-in-cell simulations of the interaction between the solar wind and a dipole field to study the formation of the bow shock and magnetosphere. A self-reforming bow shock ahead of a dipole field is presented by using relatively high temporal-spatial resolutions. We find that (1) the bow shock and the magnetosphere are formed and reach a quasi-stable state after several ion cyclotron periods, and (2) under the B z southward solar wind condition, the bow shock undergoes a self-reformation for low β i and high M A . Simultaneously, a magnetic reconnection in the magnetotail is found. For high β i and low M A , the shock becomes quasi-stationary, and the magnetotail reconnection disappears. In addition, (3) the magnetopause deflects the magnetosheath plasmas. The sheath particles injected at the quasi-perpendicular region of the bow shock can be convected downstream of an oblique shock region. A fraction of these sheath particles can leak out from the magnetosheath at the wings of the bow shock. Hence, the downstream situation is more complicated than that for a planar shock produced in local simulations.

  6. E-BOSS: an Extensive stellar BOw Shock Survey. I: Methods and First Catalogue

    CERN Document Server

    Peri, C S; Brookes, D P; Stevens, I R; Isequilla, N

    2011-01-01

    CONTEXT: Bow shocks are produced by many astrophysical objects where shock waves are present. Stellar bow-shocks, generated by runaway stars, have been previously detected in small numbers and well studied. Along with recent progress in model development and improved observing instruments, our knowledge of the emission produced by these objects and its origin can be better understood. AIMS: Our main goal is to produce a stellar bow-shock catalogue by applying uniform search criteria and a systematic search process. This catalogue is a starting point for statistical studies, and to address fundamental questions such as, for instance, which conditions make a stellar bow shock detectable. METHODS: By using the newest infrared data releases we carried out a search for bow shocks produced by early-type runaway stars. First, we explore whether the classical IRAS bow shock candidates of Noriega-Crespo et al. (1997) remain visible in the most recently available IR data, which has much better resolution and sensitivit...

  7. Whistler wave bursts upstream of the Uranian bow shock

    Science.gov (United States)

    Smith, Charles W.; Goldstein, Melvyn L.; Wong, Hung K.

    1989-01-01

    Observations of magnetic field wave bursts upstream of the Uranian bow shock are reported which were recorded prior to the inbound shock crossing. Three wave types are identified. One exhibits a broad spectral enhancement from a few millihertz to about 50 mHz and is seen from 17 to 10 hr prior to the inbound shock crossing. It is argued that these waves are whistler waves that have propagated upstream from the shock. A second wave type has a spacecraft frame frequency between 20 and 40 mHz, is seen only within or immediately upstream of the shock pedestal, is right-hand polarized in the spacecraft frame, and has a typical burst duration of 90 s. The third wave type has a spacecraft frame frequency of about 0.15 Hz, is seen exclusively within the shock pedestal, is left-hand polarized in the spacecraft frame, and has a burst duration lasting up to 4 min. It is argued that the low-frequency bursts are whistler waves with phase speed comparable to, but in excess of, the solar wind speed.

  8. Whistler waves associated with the Uranian bow shock - Outbound observations

    Science.gov (United States)

    Smith, Charles W.; Wong, Hung K.; Goldstein, Melvyn L.

    1991-01-01

    High-resolution magnetic field measurements from the first outbound crossing of the Uranian bowshock by the Voyager 2 spacecraft between January 27 and 30, 1986, are examined. Evidence is found of enhanced whistler wave activity in the vicinity of three shock crossings but little or no evidence of such activity elsewhere. Two wave events display two separate and simultaneous wave enhancements each. From an investigation of these events using high-resolution field data, it is concluded that they are analogous to those whistler waves upstream of the earth's bow shock that are driven by beams of electrons. An instability analysis is presented to show that a single electron beam with reasonable parameters can penetrate both of the upstream and downstream of a shock crossing. This event displays only one relatively broad spectral enhancement in the same frequency regime and is left-hand polarized in the spacecraft frame. It is argued that this event is the result of a gyrating proton distribution associated with the oblique shock.

  9. Geologic map of the Paintbrush Canyon Area, Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, R.P. [Geological Survey, Denver, CO (United States); Drake, R.M. II [Pacific Western Technologies, Ltd., Lakewood, CO (United States)

    1998-11-01

    This geologic map is produced to support site characterization studies of Yucca Mountain, Nevada, site of a potential nuclear waste storage facility. The area encompassed by this map lies between Yucca Wash and Fortymile Canyon, northeast of Yucca Mountain. It is on the southern flank of the Timber Mountain caldera complex within the southwest Nevada volcanic field. Miocene tuffs and lavas of the Calico Hills Formation, the Paintbrush Group, and the Timber Mountain Group crop out in the area of this map. The source vents of the tuff cones and lava domes commonly are located beneath the thickest deposits of pyroclastic ejecta and lava flows. The rocks within the mapped area have been deformed by north- and northwest-striking, dominantly west-dipping normal faults and a few east-dipping normal faults. Faults commonly are characterized by well developed fault scarps, thick breccia zones, and hanging-wall grabens. Latest movement as preserved by slickensides on west-dipping fault scarps is oblique down towards the southwest. Two of these faults, the Paintbrush Canyon fault and the Bow Ridge fault, are major block-bounding faults here and to the south at Yucca Mountain. Offset of stratigraphic units across faults indicates that faulting occurred throughout the time these volcanic units were deposited.

  10. Comparison of accelerated ion populations observed upstream of the bow shocks at Venus and Mars

    Directory of Open Access Journals (Sweden)

    M. Yamauchi

    2011-03-01

    Full Text Available Foreshock ions are compared between Venus and Mars at energies of 0.6~20 keV using the same ion instrument, the Ion Mass Analyser, on board both Venus Express and Mars Express. Venus Express often observes accelerated protons (2~6 times the solar wind energy that travel away from the Venus bow shock when the spacecraft location is magnetically connected to the bow shock. The observed ions have a large field-aligned velocity compared to the perpendicular velocity in the solar wind frame, and are similar to the field-aligned beams and intermediate gyrating component of the foreshock ions in the terrestrial upstream region. Mars Express does not observe similar foreshock ions as does Venus Express, indicating that the Martian foreshock does not possess the intermediate gyrating component in the upstream region on the dayside of the planet. Instead, two types of gyrating protons in the solar wind frame are observed very close to the Martian quasi-perpendicular bow shock within a proton gyroradius distance. The first type is observed only within the region which is about 400 km from the bow shock and flows tailward nearly along the bow shock with a similar velocity as the solar wind. The second type is observed up to about 700 km from the bow shock and has a bundled structure in the energy domain. A traversal on 12 July 2005, in which the energy-bunching came from bundling in the magnetic field direction, is further examined. The observed velocities of the latter population are consistent with multiple specular reflections of the solar wind at the bow shock, and the ions after the second reflection have a field-aligned velocity larger than that of the de Hoffman-Teller velocity frame, i.e., their guiding center has moved toward interplanetary space out from the bow shock. To account for the observed peculiarity of the Martian upstream region, finite gyroradius effects of the solar wind protons compared to the radius of the bow shock curvature and

  11. Exploiting biomechanical degrees of freedom for fast and accurate changes in movement direction: coordination underlying quick bow reversals during continuous cello bowing

    Directory of Open Access Journals (Sweden)

    Julius eVerrel

    2013-04-01

    Full Text Available Theoretical and empirical evidence suggests that accurate and efficient motor performance may be achieved by task-specific exploitation of biomechanical degrees of freedom. We investigate coordination of the right arm in a task requiring a sudden yet precisely controlled reversal of movement direction: bow reversals during continuous (legato tone production on a stringed instrument. Ten advanced or professional cello players (at least ten years of practice and ten age-matched novice players took part in the study. Kinematic data from the bow and the right arm were analyzed in terms of velocity and acceleration profiles, as well as temporal coordination along the arm. As expected, experts’ bow velocity and acceleration profiles differed markedly from those of novice participants, with higher peak accelerations and quicker direction changes. Importantly, experts achieved the change in movement direction with a single acceleration peak while novices tended to use multiple smaller acceleration peaks. Experts moreover showed a proximal-distal gradient in timing and amplitudes of acceleration peaks, with earlier and lower-amplitude reversals at more proximal joints. We suggest that this coordination pattern allows generating high accelerations at the end effector while reducing the required joint torques at the proximal joints. This may underlie experts’ ability to produce fast bow reversals efficiently and with high spatiotemporal accuracy. The findings are discussed in terms of motor control theory as well as potential implications for musicians’ performance and health.

  12. A bow-shaped thermal structure traveling upstream of the zonal wind flow of Venus atmosphere

    Science.gov (United States)

    Taguchi, Makoto; Fukuhara, Tetsuya; Imamura, Takeshi; Kouyama, Toru; Nakamura, Masato; Sato, Takao M.; Ueno, Munetaka; Suzuki, Makoto; Iwagami, Naomoto; Sato, Mitsuteru; Hashimoto, George L.; Takagi, Seiko; Akatsuki Science Team

    2016-10-01

    The Longwave Infrared Camera (LIR) onboard the Japanese Venus orbiter Akatsuki acquires a snap shot of Venus in the middle infrared region, and provides a brightness temperature distribution at the cloud-top altitudes of about 65 km. Hundreds of images taken by LIR have been transferred to the ground since the successful Venus orbit insertion of Akatsuki on Dec. 7, 2015. Here we report that a bow shaped thermal structure extending from the northern high latitudes to the southern high latitudes was found in the brightness temperature map on Dec. 7, 2015, and that it lasted for four days at least surprisingly at almost same geographical position. The bow shape structure looks symmetrical with the equator, and consists of a high temperature region in east or upstream of the background strong westward wind or the super rotation of the Venus atmosphere followed by a low temperature region in west with an amplitude of 5 K. It appeared close to the evening terminator in the dayside, and seems not to have stayed in the same local time rather to have co-rotated with the slowly rotating ground where the western part of Aphrodite Continent was below the center of the bow shape. Meridionally aligned dark filaments similar to the bow shape structure in shape but in much smaller scale were also identified in the brightness temperature map on Dec. 7, and they propagated upstream of the zonal wind as well. The bow shape structure disappeared when LIR observed the same local time and longitude in the earliest opportunity on Jan. 16, 2016. Similar events, though their amplitudes were less than 1 K, were found on Apr. 15 and 26, 2016, but they appeared in different local times and longitudes. A simulation of a gravity wave generated in the lower atmosphere and propagating upward reproduces the observed bow shape structure. The bow shape structure could be a signature of transferring momentum from the ground to the upper atmosphere.

  13. Global explicit particle-in-cell simulations of the nonstationary bow shock and magnetosphere

    CERN Document Server

    Yang, Zhongwei; Liu, Ying D; Parks, George K; Wang, Rui; Lu, Quanming; Hu, Huidong

    2016-01-01

    We carry out two-dimensional global particle-in-cell simulations of the interaction between the solar wind and a dipole field to study the formation of the bow shock and magnetosphere. A self-reforming bow shock ahead of a dipole field is presented by using relatively high temporal-spatial resolutions. We find that (1) the bow shock and the magnetosphere are formed and reach a quasi-stable state after several ion cyclotron periods, and (2) under the Bz southward solar wind condition the bow shock undergoes a self-reformation for low \\b{eta}i and high MA. Simultaneously, a magnetic reconnection in the magnetotail is found. For high \\b{eta}i and low MA, the shock becomes quasi-stationary, and the magnetotail reconnection disappears. In addition, (3) the magnetopause deflects the magnetosheath plasmas. The sheath particles injected at the quasi-perpendicular region of the bow shock can be convected to downstream of an oblique shock region. A fraction of these sheath particles can leak out from the magnetosheath ...

  14. Bow shock fragmentation driven by a thermal instability in laboratory-astrophysics experiments

    CERN Document Server

    Suzuki-Vidal, F; Ciardi, A; Pickworth, L A; Rodriguez, R; Gil, J M; Espinosa, G; Hartigan, P; Swadling, G F; Skidmore, J; Hall, G N; Bennett, M; Bland, S N; Burdiak, G; de Grouchy, P; Music, J; Suttle, L; Hansen, E; Frank, A

    2015-01-01

    The role of radiative cooling during the evolution of a bow shock was studied in laboratory-astrophysics experiments that are scalable to bow shocks present in jets from young stellar objects. The laboratory bow shock is formed during the collision of two counter-streaming, supersonic plasma jets produced by an opposing pair of radial foil Z-pinches driven by the current pulse from the MAGPIE pulsed-power generator. The jets have different flow velocities in the laboratory frame and the experiments are driven over many times the characteristic cooling time-scale. The initially smooth bow shock rapidly develops small-scale non-uniformities over temporal and spatial scales that are consistent with a thermal instability triggered by strong radiative cooling in the shock. The growth of these perturbations eventually results in a global fragmentation of the bow shock front. The formation of a thermal instability is supported by analysis of the plasma cooling function calculated for the experimental conditions with...

  15. The Milky Way Project: A Citizen Science Catalog of Infrared Bow Shock Nebulae

    Science.gov (United States)

    Dixon, Don; Jayasinghe, Tharindu; Povich, Matthew S.

    2017-01-01

    We present preliminary results from the first citizen-science search for infrared stellar-wind bow shock candidates. This search uses the Milky Way project, hosted by the Zooniverse, an online platform with over 1 million volunteer citizen scientists. Milky Way Project volunteers examine 77,000 randomly-distributed Spitzer image cutouts at varying zoom levels. Volunteers mark the infrared arc of potential bow shock candidates as well as the star likely driving the nebula. We produce lists of candidates from bow shocks flagged by multiple volunteers, which after merging and final visual review form the basis for our catalog. Comparing our new catalog to a recently-published catalog of 709 infrared bow shock candidates identified by a small team of (primarily undergraduate) researchers will allow us to assess the effectiveness of citizen science for this type of search and should yield a more complete catalog. Planned studies using these large catalogs will improve constraints on the mass-loss rates for the massive stars that create these bow shock nebulae. Mass-loss rates are highly uncertain but are a critical component of evolutionary models for massive stars. This work is supported by the National Science Foundation under grants CAREER-1454334, AST-1411851 (RUI) and AST-1412845.

  16. Bow-tie antennas on a dielectric half-space - Theory and experiment

    Science.gov (United States)

    Compton, Richard C.; Mcphedran, Ross C.; Popovic, Zorana; Rebeiz, Gabriel M.; Tong, Peter P.

    1987-01-01

    A new formulation is discussed for the rigous calculation of the radiation pattern of a bow-tie antenna of finite length and infinitesimal thickness, placed on a lossless dielectric substrate. The analysis is based on a representation of the current density on the metal surface of the antenna as a sum of an imposed (quasistatic) term and a set of current modes with unknown amplitudes. Free-space fields that are expressed in terms of continuous spectra of symmetrized plane waves are matched to the current modes using the method of moments. The resulting set of equations are solved for the unknown current amplitudes. The calculations show that for increasing bow length the antenna impedance spirals rapidly to a value predicted by transmission line theory. The theory also shows that the E-plane pattern of a two-wavelength, 60-deg bow-tie antenna is dominated by low-loss current modes propagating at the dielectric wavenumber. As the bow tie narrows, the loss of the modes increases, and the dominant wavenumber tends to the quasi-static value. Pattern measurements made at 94 GHz are shown to agree well with theoretical predictions. Measurements for a long-wire antenna, a linear array of bow-tie elements, and a log-periodic antenna are also presented.

  17. The dynamics of Bow-shock Pulsar Wind Nebula: Reconstruction of multi-bubbles

    Science.gov (United States)

    Yoon, Doosoo; Heinz, Sebastian

    2014-08-01

    Bow-shock pulsar wind nebulae (PWNe) exhibit a characteristic cometary shape due to the supersonic motion of the pulsar interacting with the interstellar medium (ISM). One of the spectacular bow-shock is the Guitar Nebula, which is produced by the fast pulsar PSR B2224+65 (vpsr > 1000 km s-1 ), and consists of a bright head, a faint neck, a two larger bubbles. We present that the peculiar mophology arises from variations in the interstellar medium density. We perform 3-D hydrodynamic simulation to understand the evolution of the pulsar as its moves through the density discontinuity. We found that when the pulsar encounters the low-density medium, the pressure balance at the head of the bow shock begins to collapse, producing the second bubble. The expansion rate of the bubble is related to the properties of both the pulsar and the ambient medium. Assuming that the pulsar’s properties, including spin-down energy, are constant, we conclude that the ambient density around the second bubble should be 4.46 times larger than around the first bubble in the Guitar body. We further found that when the pulsar encounters the inclined density dicontinuity, it can produce the asymmetric shape of the bow shock observed in a subset of bow-shock PWNe including J2124-3358.

  18. Bow Shocks from Neutron Stars Scaling Laws and HST Observations of the Guitar Nebula

    CERN Document Server

    Chatterjee, S

    2002-01-01

    The interaction of high-velocity neutron stars with the interstellar medium produces bow shock nebulae, where the relativistic neutron star wind is confined by ram pressure. We present multi-wavelength observations of the Guitar Nebula, including narrow-band H-alpha imaging with HST/WFPC2, which resolves the head of the bow shock. The HST observations are used to fit for the inclination of the pulsar velocity vector to the line of sight, and to determine the combination of spindown energy loss, velocity, and ambient density that sets the scale of the bow shock. We find that the velocity vector is most likely in the plane of the sky. We use the Guitar Nebula and other observed neutron star bow shocks to test scaling laws for their size and H-alpha emission, discuss their prevalence, and present criteria for their detectability in targeted searches. The set of H-alpha bow shocks shows remarkable consistency, in spite of the expected variation in ambient densities and orientations. Together, they support the ass...

  19. Flow separation control by using bowed blade in highly loaded turbine cascades

    Institute of Scientific and Technical Information of China (English)

    YAMAMOTO; Atsumasa

    2009-01-01

    Due to the serious flow separations and centralized vortices,there are high secondary losses in highly loaded turbines.It is imperative to find measures to control the flow separation and vortices hence improve the turbine performance.This paper reports our recent progress on flow separation and vor-tices control in highly loaded turbine cascades by using bowed blades.Two sets of highly loaded tur-bine cascades with the turning angles of 113° and 160°,and each with 7 bowed blade angles 0°(straight),±10°,±20° and ±30° were experimentally investigated.Both internal flow field measurement and flow visualization on the blade surfaces were conducted,and the effects of blade bowing on the flow topology,distribution of vorticity and the flow energy loss were discussed.The results show that,for the cascade with the turning angle of 113°,the appropriately positive bow angle could reduce the flow energy loss;whereas for the cascade with the turning angle of 160°,the well selected negative bow angle can give the better aerodynamic performance.

  20. Flow separation control by using bowed blade in highly loaded turbine cascades

    Institute of Scientific and Technical Information of China (English)

    TAN ChunQing; ZHANG HuaLiang; CHEN HaiSheng; DONG XueZhi; ZHAO HongLei; YAMAMOTO Atsumasa

    2009-01-01

    Due to the serious flow separations and centralized vortices, there are high secondary losses in highly loaded turbines. It is imperative to find measures to control the flow separation and vortices hence improve the turbine performance. This paper reports our recent progress on flow separation and vor-tices control in highly loaded turbine cascades by using bowed blades. Two sets of highly loaded tur-bine cascades with the turning angles of 113°and 160°, and each with 7 bowed blade angles 0°(straight),±10°, ±20° and ±30° were experimentally investigated. Both internal flow field measurement and flow visualization on the blade surfaces were conducted, and the effects of blade bowing on the flow topology, distribution of vorticity and the flow energy loss were discussed. The results show that, for the cascade with the turning angle of 113°, the appropriately positive bow angle could reduce the flow energy loss; whereas for the cascade with the turning angle of 160°, the well selected negative bow angle can give the better aerodynamic performance.

  1. Application of high-turning bowed compressor stator to redesign of highly loaded fan stage

    Institute of Scientific and Technical Information of China (English)

    Shaobin LI; Jiexian SU; Zhongqi WANG

    2008-01-01

    A redesign of a highly loaded fan stage by using high-turning bowed compressor stator was conducted. The original tandem stator was replaced by the highly loaded bowed stator which was applicable to highly sub-sonic flow conditions. 3D contouring technique and local modification of blade were applied to the design of the bowed blade in order to improve the aerodynamic per-formance and the matching of the rotor and stator blade rows. Performance curves at different rotating speeds and performances at different operating points for both the original fan stage and redesigned fan stage were obtained by numerical simulations. The results show that the highly loaded bowed stator can be used not only to improve the structure and the aerodynamic performances at various operating points of the compressor stage but also to pro-vide high performances at off-design conditions. It is believed that the highly loaded bowed stator can advance the design of high-performance compressor.

  2. BOW SHOCK FRAGMENTATION DRIVEN BY A THERMAL INSTABILITY IN LABORATORY ASTROPHYSICS EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki-Vidal, F.; Lebedev, S. V.; Pickworth, L. A.; Swadling, G. F.; Skidmore, J.; Hall, G. N.; Bennett, M.; Bland, S. N.; Burdiak, G.; De Grouchy, P.; Music, J.; Suttle, L. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Ciardi, A. [Sorbonne Universités, UPMC Univ. Paris 6, UMR 8112, LERMA, F-75005, Paris (France); Rodriguez, R.; Gil, J. M.; Espinosa, G. [Departamento de Fisica de la Universidad de Las Palmas de Gran Canaria, E-35017 Las Palmas de Gran Canaria (Spain); Hartigan, P. [Department of Physics and Astronomy, Rice University, 6100 S. Main, Houston, TX 77521-1892 (United States); Hansen, E.; Frank, A., E-mail: f.suzuki@imperial.ac.uk [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States)

    2015-12-20

    The role of radiative cooling during the evolution of a bow shock was studied in laboratory-astrophysics experiments that are scalable to bow shocks present in jets from young stellar objects. The laboratory bow shock is formed during the collision of two counterstreaming, supersonic plasma jets produced by an opposing pair of radial foil Z-pinches driven by the current pulse from the MAGPIE pulsed-power generator. The jets have different flow velocities in the laboratory frame, and the experiments are driven over many times the characteristic cooling timescale. The initially smooth bow shock rapidly develops small-scale nonuniformities over temporal and spatial scales that are consistent with a thermal instability triggered by strong radiative cooling in the shock. The growth of these perturbations eventually results in a global fragmentation of the bow shock front. The formation of a thermal instability is supported by analysis of the plasma cooling function calculated for the experimental conditions with the radiative packages ABAKO/RAPCAL.

  3. Average observed properties of the Earth's quasi-perpendicular and quasi-parallel bow shock

    CERN Document Server

    Czaykowska, A; Treumann, R A; Baumjohann, W

    2000-01-01

    We present a statistical analysis of 132 dayside (LT 0700-1700) bow shock crossings of the AMPTE/IRM spacecraft. We perform a superposed epoch analysis of plasma and magnetic field parameters as well as of low frequency magnetic power spectra some minutes upstream and downstream of the bow shock by dividing the events into categories depending on the angle between bow shock normal and interplanetary magnetic field and on the plasma-beta, i.e., the ratio of plasma to magnetic pressure. Downstream of the quasi-perpendicular low-beta (beta 1.0) crossings mirror waves are identified. However, there are also cases where the conditions for mirror modes are met downstream of the nearly perpendicular shock, but no mirror waves are observed.

  4. Transport of Solar Wind H+ and He++ Ions across Earth’s Bow Shock

    Science.gov (United States)

    Parks, G. K.; Lee, E.; Fu, S. Y.; Kim, H. E.; Ma, Y. Q.; Yang, Z. W.; Liu, Y.; Lin, N.; Hong, J.; Canu, P.; Dandouras, I.; Rème, H.; Goldstein, M. L.

    2016-07-01

    We have investigated the dependence of mass, energy, and charge of solar wind (SW) transport across Earth’s bow shock. An examination of 111 crossings during quiet SW in both quasi-perpendicular and quasi-parallel shock regions shows that 64 crossings had various degrees of heating and thermalization of SW. We found 22 crossings where the SW speed was flat top distribution is ˜50 Volts. We find that the temperatures of H+ and He++ beams that penetrate the shock can sometimes be nearly the same in the upstream and downstream regions, indicating little or no heating had occurred crossing the bow shock. None of the models predict that the SW can cross the bow shock without heating. Our observations are important constraints for new models of collisionless shocks.

  5. Particles upstream of the pre-dawn bow shock - ISEE-3 observations

    Energy Technology Data Exchange (ETDEWEB)

    Terasawa, T.; Scholer, M.; Hovestadt, D.; Klecker, B.; Ipavich, F.M.; Gloeckler, G.; Sanderson, T.R.; Wenzel, K.P.; Smith, E.J.

    1985-06-01

    The first observations of energetic ions (equal to or greater than 30 keV) in the region upstream of the pre-dawn bow shock (X between 0 and -60 Re inclusively) are presented. The intensity in this region is controlled by the direction of the interplanetary magnetic field (IMF) and is maximized when the IMF is around the spiral direction. The particle distributions are highly anisotropic with the anisotropy directed perpendicular to the magnetic field. In the E x B frame this perpendicular anisotropy is conserved and it is argued that the distribution is pancake-like. This indicates that the energetic particles in the pre-dawn upstream region have their origin in the near-earth upstream region, from where they are convected by the solar wind perpendicular to the magnetic field. It is therefore concluded that acceleration occurs mainly near the nose of the bow shock, and particle acceleration at the distant bow shock is weak. 15 references.

  6. Active current sheets and hot flow anomalies in Mercury's bow shock

    CERN Document Server

    Uritsky, V M; Boardsen, S A; Sundberg, T; Raines, J M; Gershman, D J; Collinson, G; Sibeck, D; Khazanov, G V; Anderson, B J; Korth, H

    2013-01-01

    Hot flow anomalies (HFAs) represent a subset of solar wind discontinuities interacting with collisionless bow shocks. They are typically formed when the normal component of motional (convective) electric field points toward the embedded current sheet on at least one of its sides. The core region of an HFA contains hot and highly deflected ion flows and rather low and turbulent magnetic field. In this paper, we report first observations of HFA-like events at Mercury identified over a course of two planetary years. Using data from the orbital phase of the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, we identify a representative ensemble of active current sheets magnetically connected to Mercury's bow shock. We show that some of these events exhibit unambiguous magnetic and particle signatures of HFAs similar to those observed earlier at other planets, and present their key physical characteristics. Our analysis suggests that Mercury's bow shock does not only mediate the flo...

  7. Bow shock nebulae of hot massive stars in a magnetized medium

    CERN Document Server

    Meyer, D M -A; Kuiper, R; Raga, A; Kley, W

    2016-01-01

    A significant fraction of OB-type, main-sequence massive stars are classified as runaway and move supersonically through the interstellar medium (ISM). Their strong stellar winds interact with their surroundings where the typical strength of the local ISM magnetic field is about 3.5-7 micro-G, which can result in the formation of bow shock nebulae. We investigate the effects of such magnetic fields, aligned with the motion of the flow, on the formation and emission properties of these circumstellar structures. Our axisymmetric, magneto-hydrodynamical simulations with optically-thin radiative cooling, heating and anisotropic thermal conduction show that the presence of the background ISM magnetic field affects the projected optical emission our bow shocks at Ha and [OIII] lambda 5007 which become fainter by about 1-2 orders of magnitude, respectively. Radiative transfer calculations against dust opacity indicate that the magnetic field slightly diminishes their projected infrared emission and that our bow shoc...

  8. An Analytical Method for Calculating the Satellite Bow Shock/Magnetopause Interception Positions and Times

    CERN Document Server

    Atanassov, Atanas Marinov

    2010-01-01

    This paper contains a presentation of analytical solution of the problem of calculating the places and moments of intersection of satellite trajectories with elements of the Earth's magnetosphere (bow shock and magnetopause). The satellite motion is presented in a Kepler's approximation. Magnetopause and bow shock are described by second-order surfaces- elliptic paraboloides. These surfaces are employed as situational conditions for determining the points of intersection they have (if any) with the satellite trajectory. The situational condition is herein transformed into the plane of Kepler's orbit, thereafter it is reduced to a second-order plane curve- quadric (ellipse or parabola). The solution of this system, containing the equation of this curve and Kepler's ellipse equation, allows determining the places where orbits intersect with the magnetopause or the bow shock. The solution of this system is suggested to be given by reducing the system to a fourth-order equation.

  9. An IRAS/ISSA Survey of Bow Shocks Around Runaway Stars

    Science.gov (United States)

    van Buren, Dave; Noriega-Crespo, Alberto; Dgani, Ruth

    1995-12-01

    We searched the IRAS data for bow shock-like objects like those known around ζ Oph and α Cam near the positions of 188 runaway stars. Based primarily on the presence and morphology of excess 60 μm emission we identify 58 candidate bow shocks, for which we determine photometric and morphological parameters. Previously only a dozen or so were known. Well-resolved structures are present around 25 stars. A comparison of the distribution of symmetry axes of the infrared nebulae with the proper motions of the stars indicate the two directions are very significantly aligned. The observed alignment strongly suggests that the structures we see arise from the interaction of stellar winds with the interstellar medium, justifying the identification of these far-infrared objects as stellar wind bow shocks.

  10. Prenatal diagnosis of metatropic dysplasia: beware of the pseudo-bowing sign

    Energy Technology Data Exchange (ETDEWEB)

    Garel, Catherine [Trousseau Hospital, University Hospitals of the East of Paris, Department of Radiology, Paris (France); Hopital d' Enfants Armand-Trousseau, Department of Radiology, Paris (France); Dhouib, Amira; Sileo, Chiara; Ducou le Pointe, Hubert [Trousseau Hospital, University Hospitals of the East of Paris, Department of Radiology, Paris (France); Cormier-Daire, Valerie [Paris Descartes University, Sorbonne Paris Cite, Necker-Enfants-Malades Hospital, Department of Genetics, Paris (France)

    2014-03-15

    Metatropic dysplasia is a very rare form of osteochondrodysplasia with only one case of prenatal diagnosis described in the literature. It is characterized by marked shortening of the long bones with severe platyspondyly and dumbbell-shape metaphyses. We report a case of metatropic dysplasia that was diagnosed prenatally and describe the findings on US and CT. The pregnancy was terminated and the post-mortem radiographs are shown. The woman had been referred for short and bowed long bones. Severe metaphyseal enlargement was a misleading finding because it had been misinterpreted as limb bowing. Thus when abnormal curvature of the long bones is observed at prenatal US, attention should be drawn not only to the diaphyses but also to the metaphyses because severe metaphyseal enlargement might be responsible for pseudo-bowing. (orig.)

  11. Intervention of laser periphery iridectomy to posterior iris bowing in high myopic eyes

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-tao; WANG Ning-li; LI Shu-ning

    2012-01-01

    Background For some high myopic patients with posterior iris bowing,laser periphery iridectomy should be performed pre-operation to prevent pupil block glaucoma if these patients would have phakic intraocular lens implantation to correct high myopia.So we had the opportunity to analysis the influence of laser iridectomy on posterior iris bowing.Methods Eighteen high myopic patients with posterior iris bowing (11 males and 7 females) were involved in the study in Beijing Tongren Eye Center from March 2008 to July 2008.Phakic intraocular lens were implanted to correct their ametropia.The mean age was (32±6) years (range,25-40 years).The center anterior chamber depth,the pupil diameter,the posterior iris bowing depth and the anterior chamber angle were measured with anterior segment coherence tomography (AS-OCT) under the normal condition,myosis condition induced by 2% pilocarpine,laser periphery iridectomy after myosis,and 2% pilocarpine eluting condition respectively.Results There was no significant difference of center anterior chamber depth under the four conditions (P=0.512).The pupil constricted after pilocarpine (P=0.001).After laser iridectomy performed and pilocarpine eluted,posterior iris bowing depth reduced more than that in normal condition (P=0.003).The anterior chamber angle reduced significantly after laser periphery iridectomy and pilocarpine eluted (P=0.012).Conclusion Laser periphery iridectomy can reduce the posterior iris bowing,which might be due to the change in aqueous circulate pathway.

  12. Accuracy of two face-bow/semi-adjustable articulator systems in transferring the maxillary occlusal cant

    Directory of Open Access Journals (Sweden)

    Nazia Nazir

    2012-01-01

    Full Text Available Context: The precision of an arbitrary face-bow in accurately transferring the orientation of the maxillary cast to the articulator has been questioned because the maxillary cast is mounted in relation to arbitrary measurements and anatomic landmarks that vary among individuals. Aim: This study was intended to evaluate the sagittal inclination of mounted maxillary casts on two semi-adjustable articulator/face-bow systems in comparison to the occlusal cant on lateral cephalograms. Materials and Methods: Maxillary casts were mounted on the Hanau and Girrbach semi-adjustable articulators following face-bow transfer with their respective face-bows. The sagittal inclination of these casts was measured in relation to the fixed horizontal reference plane using physical measurements. Occlusal cant was measured on lateral cephalograms. SPSS software (version 11.0, Chicago, IL, USA was used for statistical analysis. Repeated measures analysis of variance and Tukey′s tests were used to evaluate the results (P < 0.05. Results: Comparison of the occlusal cant on the articulators and cephalogram revealed statistically significant differences. Occlusal plane was steeper on Girrbach Artex articulator in comparison to the Hanau articulator. Conclusion: Within the limitations of this study, it was found that the sagittal inclination of the mounted maxillary cast achieved with Hanau articulator was closer to the cephalometric occlusal cant as compared to that of the Girrbach articulator. Among the two articulators and face-bow systems, the steepness of sagittal inclination was greater on Girrbach semi-adjustable articulator. Different face-bow/articulator systems could result in different orientation of the maxillary cast, resulting in variation in stability, cuspal inclines and cuspal heights.

  13. Multispacecraft observations of the terrestrial bow shock and magnetopause during extreme solar wind disturbances

    Directory of Open Access Journals (Sweden)

    M. Tátrallyay

    2012-12-01

    Full Text Available Three events are discussed from the declining phase of the last solar cycle when the magnetopause and/or the bow shock were observed unusually close to the Earth due to major interplanetary disturbances. The observed extreme locations of the discontinuities are compared with the predictions of three magnetopause and four bow shock models which describe them in considerably different ways using statistical methods based on observations. A new 2-D magnetopause model is introduced (based on Verigin et al., 2009 which takes into account the pressure of the compressed magnetosheath field raised by the interplanetary magnetic field (IMF component transverse to the solar wind flow. The observed magnetopause crossings could be predicted with a reasonable accuracy (0.1–0.2 RE by one of the presented models at least. For geosynchronous magnetopause crossings observed by the GOES satellites, (1 the new model provided the best predictions when the IMF was extremely large having a large negative Bz component, and (2 the predictions of the model of Shue et al. (1998 agreed best with the observations when the solar wind dynamic pressure was extremely large. The magnetopause crossings close to the cusp observed by the Cluster spacecraft were best predicted by the 3-D model of Lin et al. (2010. The applied empirical bow shock models and the 3-D semi-empiric bow shock model combined with magnetohydrodynamic (MHD solution proved to be insufficient for predicting the observed unusual bow shock locations during large interplanetary disturbances. The results of a global 3-D MHD model were in good agreement with the Cluster observations on 17 January 2005, but they did not predict the bow shock crossings on 31 October 2003.

  14. Asymmetric Outer Bow Length and Cervical Headgear Force System: 3D Analysis Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Allahyar Geramy

    2015-10-01

    Full Text Available Objectives: This study sought to assess distal and lateral forces and moments of asymmetric headgears by variable outer bow lengths.Materials and Methods: Four 3D finite element method (FEM models of a cer- vical headgear attached to the maxillary first molars were designed in SolidWorks2010 software and transferred to ANSYS Workbench ver. 11 software. Modelscontained the first molars, their periodontal ligament (PDL, cancellous and cor- tical bones, a mesiodistal slice of the maxillae and the headgear. Models were the same except for the outer bow length in headgears. The headgear was symmetric in model 1. In models 2 to 4, the headgears were asymmetric in length with dif- ferences of 5mm, 10mm and 15mm, respectively. A 2.5 N force in horizontal plane was applied and the loading manner of each side of the outer bow was cal- culated trigonometrically using data from a volunteer.Results: The 15mm difference in outer bow length caused the greatest difference in lateral (=0.21 N and distal (= 1.008 N forces and also generated moments (5.044 N.mm.Conclusion: As the difference in outer bow length became greater, asymmetric effects increased. Greater distal force in the longer arm side was associated with greater lateral force towards the shorter arm side and more net yawing moment. Clinical Relevance:A difference range of 1mm to 15 mm of length in cervical headgear can be consi-dered as a safe length of outer bow shortening in clinical use.

  15. Acute mountain sickness

    Science.gov (United States)

    High altitude cerebral edema; Altitude anoxia; Altitude sickness; Mountain sickness; High altitude pulmonary edema ... Acute mountain sickness is caused by reduced air pressure and lower oxygen levels at high altitudes. The faster you ...

  16. Electron - whistler interaction at the Earth`s bow shock: 2. Electron pitch angle diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Veltri, P.; Zimbardo, G. [Universita della Calabria, Cosenza (Italy)

    1993-08-01

    In this paper the authors further examine the interactions of whistler waves with electrons in the bow shock, simulating a crossing made on Nov 7, 1977. The authors consider the effects of whistler waves and electrostatic noise on the electron distribution function, using a Monte Carlo technique. Their simulations are able to reproduce the moments of the distribution function, including spatial and velocity profiles. They conclude that the fields in the bow shock accelerate electrons, creating asymmetric distributions, which are filled in due to diffusion caused by the electrostatic noise, and which have the velocity distributions balanced due to pitch angle scattering of parallel electrons from whistler waves.

  17. A benchmark study of procedures for analysis of axial crushing of bulbous bows

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Pedersen, Preben Terndrup

    2008-01-01

    Simplified methods to estimate mean axial crushing forces of plated structures are reviewed and applied to a series of experimental results for axial crushing of large-scale bulbous bow models. Methods based on intersection unit elements such as L-, T- and X-type elements as well as methods based...... on plate unit elements are employed in the analyses. The crushing forces and the total absorbed energy obtained by the simplified analyses are compared with those obtained from large-scale bulbous bow experiments. The accuracy and the applicability of these methods are discussed in detail....

  18. The Southeastern Sicily GPS network

    OpenAIRE

    Broccio, F.; Baldi, P.; M. Anzidei; V. Achilli; R. Velardita

    1995-01-01

    The area located between Catania and Syracuse (Southeastern Sicily), characterised by the presence of the Simeto-Scordia-Lentini graben, was affected in the past by a strong seismicity as proved by the occurrence of seismic events strong enough to reach the XI degree of the MCS scale. In particular the January 11 th, 1693 (l = XI MCS) earthquake with a magnitude over 7.5 (estimated), caused huge damage and a great loss of human lives. Following the last seismic event which occurred on Decembe...

  19. Effect of coarse woody debris manipulation on soricid and herpetofaunal communities in upland pine stands of the southeastern coastal plain.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Justin, Charles

    2009-04-01

    Abstract -The majority of studies investigating the importance of coarse woody debris (CWD) to forest- floor vertebrates have taken place in the Pacific Northwest and southern Appalachian Mountains, while comparative studies in the southeastern Coastal Plain are lacking. My study was a continuation of a long-term project investigating the importance of CWD as a habitat component for shrew and herpetofaunal communities within managed pine stands in the southeastern Coastal Plain. Results suggest that addition of CWD can increase abundance of southeastern and southern short-tailed shrews. However, downed wood does not appear to be a critical habitat component for amphibians and reptiles. Rising petroleum costs and advances in wood utilization technology have resulted in an emerging biofuels market with potential to decrease CWD volumes left in forests following timber harvests. Therefore, forest managers must understand the value of CWD as an ecosystem component to maintain economically productive forests while conserving biological diversity.

  20. Spatial distribution and frequency of precipitation during an extreme event: July 2006 mesoscale convective complexes and floods in southeastern Arizona

    Science.gov (United States)

    Griffiths, P.G.; Magirl, C.S.; Webb, R.H.; Pytlak, E.; Troch, Peter A.; Lyon, S.W.

    2009-01-01

    An extreme, multiday rainfall event over southeastern Arizona during 27-31 July 2006 caused record flooding and a historically unprecedented number of slope failures and debris flows in the Santa Catalina Mountains north of Tucson. An unusual synoptic weather pattern induced repeated nocturnal mesoscale convective systems over southeastern Arizona for five continuous days, generating multiday rainfall totals up to 360 mm. Analysis of point rainfall and weather radar data yielded storm totals for the southern Santa Catalina Mountains at 754 grid cells approximately 1 km ?? 1 km in size. Precipitation intensity for the 31 July storms was not unusual for typical monsoonal precipitation in this region (recurrence interval (RI) 50 years and individual grid cells had RI exceeding 1000 years. The 31 July storms caused the watersheds to be essentially saturated following 4 days of rainfall. Copyright 2009 by the American Geophysical Union.

  1. Postglacial vegetation history of Mitkof Island, Alexander Archipelago, southeastern Alaska

    Science.gov (United States)

    Ager, Thomas A.; Carrara, Paul E.; Smith, Jane L.; Anne, Victoria; Johnson, Joni

    2010-03-01

    An AMS radiocarbon-dated pollen record from a peat deposit on Mitkof Island, southeastern Alaska provides a vegetation history spanning ˜12,900 cal yr BP to the present. Late Wisconsin glaciers covered the entire island; deglaciation occurred > 15,400 cal yr BP. The earliest known vegetation to develop on the island (˜12,900 cal yr BP) was pine woodland ( Pinus contorta) with alder ( Alnus), sedges (Cyperaceae) and ferns (Polypodiaceae type). By ˜12,240 cal yr BP, Sitka spruce ( Picea sitchensis) began to colonize the island while pine woodland declined. By ˜11,200 cal yr BP, mountain hemlock ( Tsuga mertensiana) began to spread across the island. Sitka spruce-mountain hemlock forests dominated the lowland landscapes of the island until ˜10,180 cal yr BP, when western hemlock ( Tsuga heterophylla) began to colonize, and soon became the dominant tree species. Rising percentages of pine, sedge, and sphagnum after ˜7100 cal yr BP may reflect an expansion of peat bog habitats as regional climate began to shift to cooler, wetter conditions. A decline in alders at that time suggests that coastal forests had spread into the island's uplands, replacing large areas of alder thickets. Cedars ( Chamaecyparis nootkatensis, Thuja plicata) appeared on Mitkof Island during the late Holocene.

  2. Postglacial vegetation history of Mitkof Island, Alexander Archipelago, southeastern Alaska

    Science.gov (United States)

    Ager, T.A.; Carrara, P.E.; Smith, Jody L.; Anne, V.; Johnson, J.

    2010-01-01

    An AMS radiocarbon-dated pollen record from a peat deposit on Mitkof Island, southeastern Alaska provides a vegetation history spanning ???12,900??cal yr BP to the present. Late Wisconsin glaciers covered the entire island; deglaciation occurred > 15,400??cal yr BP. The earliest known vegetation to develop on the island (???12,900??cal yr BP) was pine woodland (Pinus contorta) with alder (Alnus), sedges (Cyperaceae) and ferns (Polypodiaceae type). By ???12,240??cal yr BP, Sitka spruce (Picea sitchensis) began to colonize the island while pine woodland declined. By ???11,200??cal yr BP, mountain hemlock (Tsuga mertensiana) began to spread across the island. Sitka spruce-mountain hemlock forests dominated the lowland landscapes of the island until ???10,180??cal yr BP, when western hemlock (Tsuga heterophylla) began to colonize, and soon became the dominant tree species. Rising percentages of pine, sedge, and sphagnum after ???7100??cal yr BP may reflect an expansion of peat bog habitats as regional climate began to shift to cooler, wetter conditions. A decline in alders at that time suggests that coastal forests had spread into the island's uplands, replacing large areas of alder thickets. Cedars (Chamaecyparis nootkatensis, Thuja plicata) appeared on Mitkof Island during the late Holocene.

  3. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification.

    Directory of Open Access Journals (Sweden)

    Fang Yan

    Full Text Available Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie analysis was proposed by mapping bow-tie analysis into Bayesian network (BN. Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures.

  4. Modeling and numerical investigation of the inlet circumferential fluctuations of swept and bowed blades

    Science.gov (United States)

    Tang, Mingzhi; Jin, Donghai; Gui, Xingmin

    2017-02-01

    The circumferential fluctuation (CF) source terms induced by the inviscid blade force can affect the inlet distribution of flow parameters and radial equilibrium of swept and bowed blades. However, these phenomena cannot be adequately described by throughflow methods based on the axisymmetric assumption. A transport model for the CF stresses is proposed and correlated to the distribution of circulation to reflect the effect of the inviscid blade force. To investigate the effect of the inlet CFs on swept and bowed blades, the model is integrated into a throughflow model and applied to a series of cascades with different sweep and bow angles. For swept cascades, the CF source terms change the distributions of incidence angles, as well as the radial equilibrium at the inlet of the blade passage. And the influence is enhanced as the absolute value of the sweep angle increases. For bowed cascades, the distributions of incidence angles are also altered. For both cases, the model can offer a good prediction of the inlet CF source terms, and prove to exert a better prediction of blade design key parameters such as flow angles.

  5. Further evidence for a dynamically generated secondary bow in $^{13}$C+$^{12}$C rainbow scattering

    CERN Document Server

    Ohkubo, S; Ogloblin, A A

    2015-01-01

    The existence of a secondary bow is confirmed for 13C+12C nuclear rainbow scattering in addition to the 16O+12C system. This is found by studying the experimental angular distribution of 13C+12C scattering at the incident 13C energy $E_L$=250 MeV with an extended double folding (EDF) model that describes all the diagonal and off-diagonal coupling potentials derived from the microscopic wave functions for 12C using a density-dependent nucleon-nucleon force. The Airy minimum at \\theta$ $\\approx$70$^\\circ$, which is not reproduced by a conventional folding potential, is revealed to be a secondary bow generated dynamically by a coupling to the excited state 2+ (4.44 MeV) of 12C. The essential importance of the quadruple {\\it Y2} term (reorientation term) of potential of the excited state 2+ of 12C for the emergence of a secondary bow is found. The mechanism of the secondary bow is intuitively explained by showing how the trajectories are refracted dynamically into the classically forbidden angular region beyond t...

  6. Observed Foreshock Ions which are Actually Behind the Martian Bow Shock

    Science.gov (United States)

    Frahm, Rudy A.; Yamauchi, Masatoshi; Winningham, J. David; Lundin, Rickard; Sharber, James R.; Nilsson, Hans; Coates, Andrew J.; Mukherjee, Joey

    2016-04-01

    The Mars Express (MEx) Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3) experiment contains ion and electron instruments for conducting plasma measurements. On January 23, 2012, during in-bound travel of MEx in the southern hemisphere of Mars traveling from its dawn side toward periapsis at dusk, the plasma instruments measured foreshock-like ion beams extending from outside the bow shock and into the magnetosphere, continuing to a distance of about a proton gyroradius from the bow shock. These ion beams were mostly protons, were observed to have energies greater than solar wind protons, and were not gyrating, in agreement with reflections of the solar wind proton beam. Furthermore, in the foreshock region, the ion energy gradually decreased toward the magnetosheath, in agreement with an acceleration by an outward-directed electric field in the bow shock. The observations also suggest that this electric field exists even inside the magnetosheath, within the distance of a proton gyroradius from the bow shock.

  7. A three-dimensional analysis of finger and bow string movements during the release in archery.

    Science.gov (United States)

    Horsak, Brian; Heller, Mario

    2011-05-01

    The aim of this paper was to examine finger and bow string movements during archery by investigating a top Austrian athlete (FITA score = 1233) under laboratory conditions. Maximum lateral bow string deflection and angular displacements for index, third, and ring fingers between the full draw position and the end of the release were quantified using a motion tracking system. Stepwise multiple regression analyses were used to determine whether bow string deflection and finger movements are predictive for scoring. Joint ranges of motion during the shot itself were large in the proximal and distal interphalangeal joints, and much smaller in the metacarpophalangeal joints. Contrary to our expectations, greater deflection leads to higher scores (R2 = .18, p < .001) and the distal interphalangeal joint of the third finger weakly predicts the deflection (R2 = .11, p < .014). More variability in the joint angles of the third finger was found in bad shots than in good shots. Findings in this study let presume that maximum lateral bow string deflection does not adversely affect the archer's performance.

  8. Cherkis bow varieties and Coulomb branches of quiver gauge theories of affine type $A$

    CERN Document Server

    Nakajima, Hiraku

    2016-01-01

    We show that Coulomb branches of quiver gauge theories of affine type $A$ are Cherkis bow varieties, which have been introduced as ADHM type description of moduli space of instantons on the Taub-NUT space equivariant under a cyclic group action.

  9. Exoplanet Transit Variability: Bow Shocks and Winds Around HD 189733b

    CERN Document Server

    Llama, J; Jardine, M; Wood, K; Fares, R; Gombosi, T I

    2013-01-01

    By analogy with the solar system, it is believed that stellar winds will form bow shocks around exoplanets. For hot Jupiters the bow shock will not form directly between the planet and the star, causing an asymmetric distribution of mass around the exoplanet and hence an asymmetric transit. As the planet orbits thorough varying wind conditions, the strength and geometry of its bow shock will change, thus producing transits of varying shape. We model this process using magnetic maps of HD 189733 taken one year apart, coupled with a 3D stellar wind model, to determine the local stellar wind conditions throughout the orbital path of the planet. We predict the time-varying geometry and density of the bow shock that forms around the magnetosphere of the planet and simulate transit light curves. Depending on the nature of the stellar magnetic field, and hence its wind, we find that both the transit duration and ingress time can vary when compared to optical light curves. We conclude that consecutive near-UV transit...

  10. Extended Red Objects and Stellar Wind Bow Shocks in the Carina Nebula

    CERN Document Server

    Sexton, Remington O; Smith, Nathan; Babler, Brian L; Meade, Marilyn R; Rudolph, Alexander L

    2014-01-01

    We report the results of infrared photometry on 39 extended red objects (EROs) in the Carina Nebula, observed with the Spitzer Space Telescope. Most EROs are identified by bright, extended 8.0 um emission, which ranges from 10'' to 40'' in size, but our sample also includes 4 EROs identified by extended 24 um emission. Of particular interest are nine EROs associated with late O or early B-type stars and characterized by arc-shaped morphology, suggesting dusty, stellar-wind bow shocks. These objects are preferentially oriented towards the central regions of the Carina Nebula, suggesting that these bow shocks are generally produced by the interactions of OB winds with the bulk expansion of the H II region rather than high proper motion. We identify preferred regions of mid-infrared color space occupied by our bow shock candidates, which also contain bow shock candidates in M17 and RCW 49 but are well-separated from polycyclic aromatic hydrocarbon emission or circumstellar discs. Color cuts identify an additiona...

  11. Double bow shocks around young, runaway red supergiants: application to Betelgeuse

    CERN Document Server

    Mackey, Jonathan; Neilson, Hilding R; Langer, Norbert; Meyer, Dominique M -A

    2012-01-01

    A significant fraction of massive stars are moving supersonically through the interstellar medium (ISM), either due to disruption of a binary system or ejection from their parent star cluster. The interaction of their wind with the ISM produces a bow shock. In late evolutionary stages these stars may undergo rapid transitions from red to blue and vice versa on the Hertzsprung-Russell diagram, with accompanying rapid changes to their stellar winds and bow shocks. Recent 3D simulations of the bow shock produced by the nearby runaway red supergiant (RSG) Betelgeuse, under the assumption of a constant wind, indicate that the bow shock is very young (<30000 years old), hence Betelgeuse may have only recently become a RSG. To test this possibility, we have calculated stellar evolution models for single stars which match the observed properties of Betelgeuse in the RSG phase. The resulting evolving stellar wind is incorporated into 2D hydrodynamic simulations in which we model a runaway blue supergiant (BSG) as i...

  12. "Heaven Starts at Your Parents' Feet": Adolescent Bowing to Parents and Associated Spiritual Attitudes

    Science.gov (United States)

    Thanissaro, Phra Nicholas

    2010-01-01

    In a quantitative survey of religious attitudes and practices in a multi-religious sample of 369 school pupils aged between 13 and 15 in London, the practice of bowing to parents was found widespread in 22% of adolescents spanning several religious affiliations and ethnicities--especially Buddhists, Hindus and those of Indian, African and…

  13. X-ray Emission Line Profiles from Wind Clump Bow Shocks in Massive Stars

    CERN Document Server

    Ignace, R; Cassinelli, J P

    2012-01-01

    The consequences of structured flows continue to be a pressing topic in relating spectral data to physical processes occurring in massive star winds. In a preceding paper, our group reported on hydrodynamic simulations of hypersonic flow past a rigid spherical clump to explore the structure of bow shocks that can form around wind clumps. Here we report on profiles of emission lines that arise from such bow shock morphologies. To compute emission line profiles, we adopt a two component flow structure of wind and clumps using two "beta" velocity laws. While individual bow shocks tend to generate double horned emission line profiles, a group of bow shocks can lead to line profiles with a range of shapes with blueshifted peak emission that depends on the degree of X-ray photoabsorption by the interclump wind medium, the number of clump structures in the flow, and the radial distribution of the clumps. Using the two beta law prescription, the theoretical emission measure and temperature distribution throughout the...

  14. Polarization signatures of bow shocks: A diagnostic tool to constrain the properties of stellar winds and ISM

    Science.gov (United States)

    Shrestha, Manisha; Hoffman, Jennifer L.; Nielson, Hilding R.; Ignace, Richard

    2017-01-01

    When a stellar wind traveling at supersonic speed interacts with almost stationary ISM, a bow shock shape is formed. By studying a bow shock, we can obtain information about the properties of the stellar wind as well as the surrounding ISM. Bow shocks are asymmetric structures, and thus produce net polarization even if they are unresolved. Hence, polarization studies of bow shocks can provide complementary constraints on their properties.We simulate the polarization signatures of circumstellar material with bow shock geometries using a Monte Carlo radiative transfer code called SLIP. We use the analytic solution from Wilkin (1996) to define the geometry and mass surface density of the bow shock in our models. We present results from our simulations showing how changing CSM optical depth, CSM albedo, photon source, and scattering particles (electrons or different types of dust particles) affects the observed polarization in both resolved and unresolved cases. In the optically thin regime of the unresolved electron-scattering case, the polarization peaks at an inclination angle of 90°, in agreement with analytical single-scattering models. In optically thick cases, a second polarization peak appears near 130°, which we propose is due to multiple scattering. Given these results, an observed polarization value can constrain the inclination of an unresolved bow shock to two possible angles, which in turn constrain the motion of the star. In case of resolved bow shocks, our simulations produce polarization maps which we compare with observations.We also present results from our dust-scattering simulations, which show that multicolor broadband polarization observations can constrain the characteristics of the dust in a resolved or unresolved bow shock-shaped CSM configuration.

  15. THE ROLE OF PICKUP IONS ON THE STRUCTURE OF THE VENUSIAN BOW SHOCK AND ITS IMPLICATIONS FOR THE TERMINATION SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    Lu Quanming; Shan Lican; Zhang Tielong; Wu Mingyu; Wang Shui [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China); Zank, Gary P. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Yang Zhongwei [SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai (China); Du Aimin, E-mail: qmlu@ustc.edu.cn [Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

    2013-08-20

    The recent crossing of the termination shock by Voyager 2 has demonstrated the important role of pickup ions (PUIs) in the physics of collisionless shocks. The Venus Express (VEX) spacecraft orbits Venus in a 24 hr elliptical orbit that crosses the bow shock twice a day. VEX provides a unique opportunity to investigate the role of PUIs on the structure of collisionless shocks more generally. Using VEX observations, we find that the strength of the Venusian bow shock is weaker when solar activity is strong. We demonstrate that this surprising anti-correlation is due to PUIs mediating the Venusian bow shock.

  16. A comparative analysis of 3D flow fields between straight and bowed blades in a steam turbine

    Institute of Scientific and Technical Information of China (English)

    M.HASSANVAND; WANG Zhong-qi 王仲奇; WANG Song-tao 王松涛

    2004-01-01

    A commercial Navier-Stokes flow solver has been employed tor simulating steady subsonic flow characteristics and analyzing the comparative features of flow fields between straight and bowed blades applied to the stator of a high pressure steam turbine. For comparison, we have studied the effects of bowed blades on the wakes of stator trailing edge and horse shoe vortex in the rotor. It was found that the position of wakes for bowed blades is shifted toward the blade suction side. Also, we have discussed and compared the entropy generation and energy loss caused by dissipation mechanism within the boundary layers on the hub and shroud; and temperature gradient in meridional plane.

  17. Mountain Plover [ds109

    Data.gov (United States)

    California Department of Resources — Point locations representing observations of mountain plover (Charadrius montanus) feeding and roosting flocks (and occasional individuals) documented during an...

  18. Butterfly Surveys in Southeastern North Dakota : 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goal of this study was to inventory butterflies and skippers on a number of wetland prairie sites in southeastern North Dakota, and pinpoint the location and...

  19. Butterfly Surveys in Southeastern North Dakota : 1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goal of this study was to inventory butterflies and skippers on a number of wetland prairie sites in southeastern North Dakota, and pinpoint the location and...

  20. Assessing habitat quality of the mountain nyala Tragelaphus buxtoni in the Bale Mountains, Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Paul H.EVANGELISTA; John NORMAN Ⅲ; Paul SWARTZINKI; Nicholas E.YOUNG

    2012-01-01

    Populations of the endangered mountain nyala Tragelaphus buxtoni are significantly threatened by the loss of critical habitat.Population estimates are tentative,and information on the species' distribution and available habitat is required for formulating immediate management and conservation strategies.To support management decisions and conservation priorities,we integrated information from a number of small-scale observational studies,interviews and reports from multiple sources to define habitat parameters and create a habitat quality model for mountain nyala in the Bale Mountains.For our analysis,we used the FunConn model,an expertise-based model that considers spatial relationships (i.e,patch size,distance) between the species and vegetation type,topography and disturbance to create a habitat quality surface.The habitat quality model showed that approximately 18,610 km2 (82.7% of our study area) is unsuitable or poor habitat for the mountain nyala,while 2,857 km2 (12.7%) and 1,026 km2 (4.6%) was ranked as good or optimal habitat,respectively.Our results not only reflected human induced habitat degradation,but also revealed an extensive area of intact habitat on the remote slopes of the Bale Mountain's southern and southeastern escarpments.This study provides an example of the roles that expert knowledge can still play in modem geospatial modeling of wildlife habitat.New geospatial tools,such as the FunConn model,are readily available to wildlife managers and allow them to perform spatial analyses with minimal software,data and training requirements.This approach may be especially useful for species that are obscure to science or when field surveys are not practical.

  1. Attenuation Distance of Low Frequency Waves Upstream of the Pre-Dawn Bow Shock: GEOTAIL snd ISEE-3 Comparison

    Science.gov (United States)

    Sugiyama, T.; Terasawa, T.; Kawano, H.; Yamamoto, T.; Kokubun, S.; Frank, L.; Ackerson, K.; Tsurutani, B.

    1994-01-01

    This paper presents a statistical study of the spatial distribution of low frequency waves in the region upstream of the pre-dawn to dawn side bow shock using both GEOTAIL and ISEE-3 magnetometer data.

  2. The Southeastern Sicily GPS network

    Directory of Open Access Journals (Sweden)

    F. Broccio

    1995-06-01

    Full Text Available The area located between Catania and Syracuse (Southeastern Sicily, characterised by the presence of the Simeto-Scordia-Lentini graben, was affected in the past by a strong seismicity as proved by the occurrence of seismic events strong enough to reach the XI degree of the MCS scale. In particular the January 11 th, 1693 (l = XI MCS earthquake with a magnitude over 7.5 (estimated, caused huge damage and a great loss of human lives. Following the last seismic event which occurred on December 13th, 1990 (Ml = 5.4 which caused heavy damage and many victims in the Catania-Syracuse area, a geodetic Global Positioning System network (GPS was set up with the aim of monitoring ground movements in one of the Italian areas subjected to high seismic risk, This "pace geodesy technique supplies high precision measurements and represent, a powerful new tool for investigating both regional stress fields and the evolution of local tectonic areas. The GPS network will allow the detection of ground movements with a centimetric accuracy through repeated surveys in time. The results obtained in two surveys carried out il1 1991 al1d 1993, are described in this paper.

  3. Half-bow sliding knot: modified suture technique for scleral fixation using the corneoscleral pocket.

    Science.gov (United States)

    Chee, Soon-Phaik

    2011-09-01

    A modified suture technique for precise knot placement in the Hoffman corneoscleral pocket technique of scleral fixation is described. Both loops of the polypropylene suture passing from the intraocular device through the sclera and conjunctiva are retrieved from the pocket. A loop of suture is pulled through 3 suture throws made using the second suture loop, forming a half bow. Centration of the intraocular lens (IOL)-capsular bag is checked. If the suture tension is too tight, the surgeon can easily undo the knot of the half-bow knot by pulling it free and can then retie the sliding knot. When the IOL-capsular bag is centered, the suture loop is cut and the free end removed. The second suture end is retrieved from the pocket, and knot tying is completed without further adjustment to the tension. Posterior pressure on the intraocular device centers it and settles the knot within the sclera at the fixation point.

  4. In situ plume radiance measurements from the bow shock ultraviolet 2 rocket flight

    Science.gov (United States)

    Erdman, Peter W.; Zipf, Edward C.; Espy, Patrick; Howlett, Carl; Christou, Carol; Levin, Deborah A.; Collins, Robert J.; Candler, Graham V.

    1993-10-01

    The ultraviolet spectrum (200-400 nm) of the plumes generated by the second- and third-stage engines of a Strypi XI rocket and of the Mach 17 re-entry bow shock were obtained by a sounding rocket experiment launched from the Barking Sands Research Range (Kauai, Hawaii) on February 18, 1991 at 14:30 GMT. The re-entry optical data were obtained as the payload descended from 120 to 65 km with a vehicle velocity of 5.1 km/s. The intensities of the vacuum ultraviolet resonance radiation emitted by atomic oxygen and hydrogen in the bow shock at 130.4 and 121.5 nm, respectively, were also measured. Complementary Langmuir probe measurements provided data on the total plasma density and electron temperature in the boundary layer.

  5. The Effect of Metallic TPS Panel Bowing on the Surface Heating of the X-33 Vehicle

    Science.gov (United States)

    Palmer, Grant; Kontinos, Dean; Langhoff, Stephen R. (Technical Monitor)

    1997-01-01

    The thermal protection system of the windward surface of the X-33 vehicle consists of metallic honeycomb sandwich panels. Thermal gradients experienced during the descent phase of the trajectory result in a different rate of thermal expansion between the inner and outer face sheets of the metallic panels. This causes the panels to bow outward when the temperature of the outer face sheet is larger than that of the inner face sheet and inward when the temperature of the outer face sheet is less than that of he inner face sheet. This results in a quilted-type body surface. Using computational fluid dynamic analysis, this study will determine the effect the metallic TPS panel bowing has on the surface heating.

  6. Nonthermal ions and associated magnetic field behavior at a quasi-parallel earth's bow shock

    Science.gov (United States)

    Wilkinson, W. P.; Pardaens, A. K.; Schwartz, S. J.; Burgess, D.; Luehr, H.; Kessel, R. L.; Dunlop, M.; Farrugia, C. J.

    1993-01-01

    Attention is given to ion and magnetic field measurements at the earth's bow shock from the AMPTE-UKS and -IRM spacecraft, which were examined in high time resolution during a 45-min interval when the field remained closely aligned with the model bow shock normal. Dense ion beams were detected almost exclusively in the midst of short-duration periods of turbulent magnetic field wave activity. Many examples of propagation at large elevation angles relative to the ecliptic plane, which is inconsistent with reflection in the standard model shock configuration, were discovered. The associated waves are elliptically polarized and are preferentially left-handed in the observer's frame of reference, but are less confined to the maximum variance plane than other previously studied foreshock waves. The association of the wave activity with the ion beams suggests that the former may be triggered by an ion-driven instability, and possible candidates are discussed.

  7. Dissecting a Molecular Shock: Spatially Resolved H2 Line Ratios Across the HH7 Bow Shock

    Science.gov (United States)

    Pike, Rosemary E.; Geballe, Thomas R.; Burton, Michael G.; Chrysostomou, Antonio; Brand, Peter

    2015-01-01

    We report on a detailed study of the physics of molecular shocks using Gemini NIFS (Near-Infrared Field Spectrometer) K-band spectra of a 3.'2 x 2.'9 region near the tip of the HH7 bow shock. The IFU data have an angular resolution of 0.3", much higher resolution then in any previous study of a molecular shock, and a velocity resolution of 60 km/s. We have detected 20 H2 emission lines with upper state energies as high as 28,000 K, and 6 additional unidentified lines which share the same bow shock morphology as the H2. We use excitation temperatures derived from line pairs measured in 0.15' x 0.15' bins to attempt to constrain the shock type and distinguish between low velocity jump shocks, continuous shocks, and dissociative shocks in which the H2 line emission arises from newly reformed H2.

  8. Modelling multi-wavelength observational characteristics of bow shocks from runaway early type stars

    CERN Document Server

    Acreman, David M; Harries, Tim J

    2015-01-01

    We assess the multi-wavelength observable properties of the bow shock around a runaway early type star using a combination of hydrodynamical modelling, radiative transfer calculations and synthetic imaging. Instabilities associated with the forward shock produce dense knots of material which are warm, ionised and contain dust. These knots of material are responsible for the majority of emission at far infra-red, H alpha and radio wavelengths. The large scale bow shock morphology is very similar and differences are primarily due to variations in the assumed spatial resolution. However infra-red intensity slices (at 22 microns and 12 microns) show that the effects of a temperature gradient can be resolved at a realistic spatial resolution for an object at a distance of 1 kpc.

  9. Diagnosis of the Thermal Bow of a Shaft in a Three Stage Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In practice many turbo-machines driven by motors are started up to operational speed within a very short time, i.e. in less than 20 seconds. For this type of machines the compatibility of thermal deformation of the rotor structure must be taken into account in the machine design, or the thermal deformation will be constrained and a huge resultant force can cause the shaft bending and consequently resulting in violent vibrations. In this paper, detection of thermal bow of a shaft in a three stage centrifugal compressor in a petrochemical plant is presented. The diagnostic results show that the thermal bow was induced by the incompatibility of axial thermal deformation of the rotor structure. A remedial action allowing free axial thermal expansion of the outer parts of the rotor is suggested.

  10. Characterization of Saturn's bow shock: Magnetic field observations of quasi-perpendicular shocks

    CERN Document Server

    Sulaiman, A H; Dougherty, M K

    2016-01-01

    Collisionless shocks vary drastically from terrestrial to astrophysical regimes resulting in radically different characteristics. This poses two complexities. Firstly, separating the influences of these parameters on physical mechanisms such as energy dissipation. Secondly, correlating observations of shock waves over a wide range of each parameter, enough to span across different regimes. Investigating the latter has been restricted since the majority of studies on shocks at exotic regimes (such as supernova remnants) have been achieved either remotely or via simulations, but rarely by means of in-situ observations. Here we present the parameter space of MA bow shock crossings from 2004-2014 as observed by the Cassini spacecraft. We find that Saturn's bow shock exhibits characteristics akin to both terrestrial and astrophysical regimes (MA of order 100), which is principally controlled by the upstream magnetic field strength. Moreover, we determined the {\\theta}Bn of each crossing to show that Saturn's (days...

  11. FAILURES AND DEFECTS IN THE BUILDING PROCESS – APPLYING THE BOW-TIE APPROACH

    DEFF Research Database (Denmark)

    Jørgensen, Kirsten

    2009-01-01

    Function failures, defects, mistakes and poor communication are major problems for the construction sector. A Danish research project focusing on failures and defects in building processes has been carried out over the last 2 years. As the empirical element in the research, a large construction...... site was observed from the very start to the very end and all failures and defects of a certain size were recorded and analysed. The methodological approach used in this analysis was the bow-tie model from the area of safety research. It combines critical-event analysis for both causes and effects...... with event-tree analysis. The paper describes this analytical approach as an introduction to a new concept for understanding failures and defects in construction. Analysing the many critical events in the building process with the bow-tie model visualises the complexity of causes. This visualisation offers...

  12. Studies on CFD simulation of hydrodynamic phenomena with vortex flow around the bow of a blunt ship

    OpenAIRE

    上浦, 鉄平

    2014-01-01

    In the present studies, hydrodynamic phenomena with vortex flow around the bow of a blunt ship are simulated by using various CFD (Computational Fluid Dynamics) codes. In the conventional experimental studies, some flow properties in front of the bow beneath the free surface have been found out and reported; for example, a necklace vortex based on the wave breaking phenomena is the typical one. In CFD simulations, however, reliable results have not been obtained yet.In this study, the authors...

  13. Contribution from the Earth's Bow Shock to Region 1 Current under Low Alfvén Mach Numbers

    Institute of Scientific and Technical Information of China (English)

    PENG Zhong; HU You-Qiu

    2009-01-01

    @@ Using global MHD simulations of the solar wind-magnetosphere--ionosphere system, we investigate the depen-dence of the contribution from the Earth's bow shock (I1bs) to ionospheric region I field aligned current (FAC) (I1). It is found that I1bs increases with increasing southward interplanetary magnetic field (IMF) strength Bs, if the Alfven Mach number MA of the solar wind exceeds 2, a similar result as obtained by previous authors. However, if MA becomes close to or falls below 2, I1bs will decrease with B8 in both magnitude and percentage (i.e., I1bs/I1) because of the resultant reduction of the bow shock strength. Both the surface current density Jbs at the nose of the bow shock and the total bow shock current lb, share nearly the same relationship with MA, and vary non-monotonically with MA or Bs. The maximum point is found to be located at MA = 2.7. Three conclusions are then made as follows: (1) The surface current density at the nose, which is much easier to be evaluated, may be used to largely describe the behaviour of the bow shock instead of the total bow shock current. (2) The peak of the total bow shock current is reached at about MA = 2.7 when only Bs is adjusted. (3) The non-monotonic variation of the bow shock current with MA causes a similar variation of its contribution to region 1 FAC. The turning point for such contribution is found to be nearly MA= 2. The implication of these conclusions to the saturation of the ionospheric transpolar potential is briefly discussed.

  14. First Detection of a Pulsar Bow Shock Nebula in Far-UV: PSR J0437-4715

    Science.gov (United States)

    Rangelov, Blagoy; Pavlov, George G.; Kargaltsev, Oleg; Durant, Martin; Bykov, Andrei M.; Krassilchtchikov, Alexandre

    2016-11-01

    Pulsars traveling at supersonic speeds are often accompanied by cometary bow shocks seen in Hα. We report on the first detection of a pulsar bow shock in the far-ultraviolet (FUV). We detected it in FUV images of the nearest millisecond pulsar J0437-4715 obtained with the Hubble Space Telescope. The images reveal a bow-like structure positionally coincident with part of the previously detected Hα bow shock, with an apex at 10″ ahead of the moving pulsar. Its FUV luminosity, L(1250{--}2000 \\mathringA )≈ 5 × {10}28 erg s-1, exceeds the Hα luminosity from the same area by a factor of 10. The FUV emission could be produced by the shocked interstellar medium matter or, less likely, by relativistic pulsar wind electrons confined by strong magnetic field fluctuations in the bow shock. In addition, in the FUV images we found a puzzling extended (≃3″ in size) structure overlapping with the limb of the bow shock. If related to the bow shock, it could be produced by an inhomogeneity in the ambient medium or an instability in the bow shock. We also report on a previously undetected X-ray emission extending for about 5″ ahead of the pulsar, possibly a pulsar wind nebula created by shocked pulsar wind, with a luminosity L(0.5-8 keV) ˜ 3 × 1028 erg s-1. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO 12917 and GO 10568.

  15. Deflection Reduction of GaN Wafer Bowing by Coating or Cutting Grooves in the Substrates

    Institute of Scientific and Technical Information of China (English)

    SUN Tao; WANG Ming-Qing; SUN Yong-Jian; WANG Bo-Ping; ZHANG Guo-Yi; TONG Yu-Zhen; DUAN Hui-Ling

    2011-01-01

    @@ GaN films on sapphire substrates are obtained using the metal-organic chemical vapor deposition growth technique.We present two methods to reduce the GaN wafer bowing caused by the mismatch of the thermal expansion coefficients(TECs)between the film and the substrate.The first method is to use coating materials on the back side of the substrate whose TECs are smaller than that of the GaN films.The second is to cut grooves on the back side of the sapphire substrate and filling the grooves with appropriate materials(e.g., tungsten, silicon nitride).For each method, we minimize wafer bowing and even reduce it to zero.Moreover, the two methods can reduce stress concentration and suppress the propagation of cracks in the GaN/sapphire structure.%GaN films on sapphire substrates are obtained using the metal-organic chemical vapor deposition growth technique. We present two methods to reduce the GaN wafer bowing caused by the mismatch of the thermal expansion coefficients (TECs) between the film and the substrate. The first method is to use coating materials on the back side of the substrate whose TECs are smaller than that of the GaN films. The second is to cut grooves on the back side of the sapphire substrate and filling the grooves with appropriate materials (e.g., tungsten, silicon nitride).For each method, we minimize wafer bowing and even reduce it to zero. Moreover, the two methods can reduce stress concentration and suppress the propagation of cracks in the GaN/sapphire structure.

  16. [A drill-bow in Horace, Odes 3.6.7].

    Science.gov (United States)

    Moog, Ferdinand Peter

    2004-01-01

    With the short poem Odes 3.26 Horaces says--ostensibly--farewell to the subject of love. A symbol of his retreat is the order given to his followers: they ought to lay in the Temple of Venus the three objects which he has used in his night escapades struggling for the girls' love: lucida funalia (torches), vectis (jemmies), and arcus. The last words has been puzzling the scholars for centuries. Many took offence at the transmitted text and offered conjectures of their own. Some, however, defended arcus using different arguemtns, for instance that arcus refers to bows and arrows as weapons of the lascivious night-reveller. Also the author of this article retains arcus in the text. The context and grammatical construction let assume that also this noun denotes a tool of a burglar, preferably a drill driven by a fiddle-bow. Such instruments were use by carpenters, joiners, and surgeons. Apart from this, gigantic drill-bows were known among military machines. These were frequently applied in sieges. Horace might have seen descriptions and drawings of them in military handbooks which he presumably read in order to prepare himself for his short and rather inglorious career as an officer in the army of Caesar's murderers. For Romans without military experience who suddenly obtained a high rank at war this was a typical way of making good their shortcomings. The parallel between the siege of a town and the attack upon the beloved girl's house must be regarded as a poetic exaggeration; the reader should be amused by an impracticable idea. Furthermore, a possible connection between Horace's poem and the Heracles of Euripides is pointed out here for the first time. In Heracles 942-6 the hero, driven insane by Lyssa's work, asks for his bow, his arrows and siege instruments to take Mycenae, the fortress of his tormentor Eurystheus. In fact he brakes into his own bedroom and kills his spouse and his son.

  17. PENGARUH ANTI-SLAMMING BULBOUS BOW TERHADAP GERAKAN SLAMMING PADA KAPAL PERINTIS 200 DWT

    OpenAIRE

    Muhammad Iqbal; Good Rindo

    2016-01-01

    Analisis seakeeping (kemampuan olah gerak kapal) merupakan aspek penting dalam perancangan kapal. Berdasarkan analisis tersebut, dapat diketahui batas operasional dari sebuah kapal. Salah satunya adalah dapat mengetahui kemampuan kapal pada tinggi gelombang signifikan (Hs) tertentu. Memodifikasi bentuk haluan kapal dengan membuat dasar dari haluan tersebut lebih rendah dibandingkan dengan dasar lambung kapal nya (dibawah garis baseline kapal) dinamakan Anti-Slamming Bow. Pada penelitian ini, ...

  18. Laboratory studies of stagnating plasma flows with applications to inner solar system and stellar bow shocks

    Science.gov (United States)

    Weber, T. E.; Smith, R. J.; Hsu, S. C.

    2016-10-01

    Supercritical magnetized collisionless shocks are thought to play a dominant role in the overall partition of energy throughout the universe by converting flow kinetic energy to other forms such as thermal and supra-thermal populations, magnetic field enhancement, turbulence, and energetic particles. The Magnetized Shock Experiment (MSX) at LANL creates conditions similar to those of inner solar system and stellar bow shocks by accelerating hot (100s of eV during translation) dense (1022 - 1023 m-3) Field Reversed Configuration (FRC) plasmoids to 100s of km/s; resulting in β 1, collisionless plasma flows with Msonic and MAlfvén 10. The drifting FRC can be made to impinge upon a variety of static obstacles including: a strong mirror or cusp magnetic field (mimicking magnetically excited shocks such as the Earth's bow shock), plasma pileup from a solid obstacle (similar to the bow shocks of Mercury and the Moon), and a neural gas puff (bow shocks of Venus or the comets). Characteristic shock length and time scales that are both large enough to observe yet small enough to fit within the experiment, enabling study of the complex interplay of kinetic and fluid processes that mediate cosmic shocks and can generate non-thermal distributions, produce density and magnetic field enhancements much greater than predicted by fluid theory, and accelerate particles. An overview of the experimental program will be presented, including recent results. This work is supported by the U.S. DOE, Office of Science, Office of Fusion Energy Sciences under Contract No. DE-AC52-06NA25369.

  19. Increase The Absorptive Capacity Of Light Of The Photocells By Embedded In Bow-tie Antenna

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Chenguang [School of Science, Beijing University of Posts and Telecommunications, Beijing, 100876 (China); Lang Peilin [Key Laboratory of Information Photonics and Optical Communications (BUPT), Ministry of Education, Beijing 100876 (China); Zhang Ru, E-mail: napolles@sohu.com

    2011-02-01

    The application of silicon photocells has been widely used in biological and energy field, how to improve the efficiency of silicon photocells has become the research hot spots. The light absorption efficiency is not ideal, only 10% to 20% of solar energy can be transformed into electricity, the paper embeds metal bow-tie antenna in the crystals of silicon, by the field enhancement of the surface plasma, it highly increase the absorptive capacity of light of the silicon photocells.

  20. Variation of the ratio of specific heats across a detached bow shock

    Science.gov (United States)

    Chao, J. K.; Wiskerchen, M. J.

    1974-01-01

    Equations are derived which allow the ratio of specific heats behind the earth's bow shock to be evaluated if several pre-shock parameters (the specific-heat ratio, the Alfvenic Mach number, the sonic Mach number, and the angle between the shock normal at the stagnation point and the magnetic field) and the density jump across the shock are known. Numerical examples show that the dependence of the post-shock ratio on the pre-shock ratio is weak.

  1. Phenomenology of the earth's bow shock system - A summary description of experimental results

    Science.gov (United States)

    Greenstadt, E. W.

    1976-01-01

    Observational data on the earth's bow shock system are classified and characterized. Foreshock components, midshock components, and aftershock components are discussed separately. Schematic representations of the field and plasma particle parameters are elaborated, with attention given to quasi-perpendicular geometry and quasi-parallel geometry. Magnetic pulsation structure is delineated. Schematic profiles of field, particle, and wave behavior through a representative quasi-perpendicular shock crossing are displayed.

  2. Venus Express Observations of Electromagnetic Waves at the Bow Shock and Magnetosheath

    Science.gov (United States)

    Wei, H.; Russell, C.; Hart, R. A.; Strangeway, R. J.; Zhang, T.

    2015-12-01

    The interaction between the solar wind and the ionosphere of Venus forms an induced magnetosphere around the planet, which consists of regions near the planet and in its wake where magnetic pressure dominates the other pressure contributions. This induced magnetosphere and the ionosphere of Venus act as a barrier to the solar wind, leading to a bow shock with standoff distance very close the planet. Upstream of the bow shock, there is abundant wave activity generated by the shock or by the back-streaming ions and electrons from the shock. Previous studies found upstream waves with 1 Hz or lower frequencies, but Venus Express occasionally provides 128 Hz data that cover the regions up to the bow shock and allow us the search for and analyze higher frequency waves. Inside the magnetosheath and at the Venus ionopause, there are lightning-associated whistler waves detected from the 128 Hz data, which generally propagate along the magnetic field lines. Besides, there is another type of waves at such high frequencies which propagate quasi-perpendicular to the magnetic field and strongly associated with current sheets near the ionopause. They either occur at the center of a sharp current, or at the edge of a current. These waves may be generated from the free energy of currents at the ionopause and could lead to dissipation of those currents. In this paper, we perform statistical studies on the current-associated waves and examine their effects on current dissipation and on plasma heating. We examine waves at the bow shock in this higher frequency range.

  3. Coordination of degrees of freedom and stabilization of task variables in a complex motor skill: expertise-related differences in cello bowing.

    Science.gov (United States)

    Verrel, Julius; Pologe, Steven; Manselle, Wayne; Lindenberger, Ulman; Woollacott, Marjorie

    2013-02-01

    Stringed instrument bowing is a complex sensorimotor skill, involving fine regulation of bow orientation and motion relative to the string. In this study, we characterize this skill in terms of stabilization of specific bow parameters as well as the underlying use and coordination of the degrees of freedom (DOF) of the right bowing arm. Age-matched samples of 10 advanced cellists and 10 cello novices took part in the study. Kinematic bow movement data were analyzed with respect to task variables suggested by the cello teaching literature: position and orientation of the bow relative to the string, bow velocity, and timing. Joint motion of the bowing arm was analyzed in terms of movement amplitude and inter-joint coordination (principal component analysis). As expected, novices showed poorer control of bowing parameters. In addition, novices differed markedly from advanced players in the use and coordination of the DOF of the bowing arm, with the elbow and wrist showing less overall movement and a reduced proportion of variance explained by the first principal component (PC1). In contrast, larger amounts of shoulder variance were explained by PC1 in novices compared to experts. Our findings support Bernstein's theory of graded skill acquisition, according to which early stages of motor skill learning are characterized by a "freezing" of movement DOF, while later learning stages exploit the DOF, possibly following a proximal-to-distal sequence, for improved task performance.

  4. The Procedure for Determination of Special Margin Factors to Account for a Bow of the VVER-1000 Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Tsyganov, Sergey V.; Marin, Stanislav V.; Shishkov, Lev K. [Russian Research Center ' Kurchatov Institute' , 1., Kurchatov sq., 123182 Moscow (Russian Federation)

    2008-07-01

    Starting from 1980's, the problem of bow of the VVER-1000 reactor FAs and the effect of that on the operational safety is being discussed. At the initial period of time, the extension of time for dropping control rods of the control and protection system associated with this bow posed the highest threat. Later on, new more rigid structures were developed for FAs that eliminated the problems of control rods. However, bow of the VVER-1000 reactor FAs is observed up to now. The scale of this bow reduced significantly but it still effects safety. Even a minor bow available may lead to the noticeable increase of power of individual fuel pins associated with the local variation of the coolant amount. This effect must be taken into account on designing fuel loadings to eliminate the exceeding of set limitations. The introduction of additional special margins is the standard method for taking this effect into account. The present paper describes the conservative technique for the assessment of additional margins for bow of FAs of state-of-the-art designs. This technique is employed in the VVER-1000 reactor designing. The chosen conservatism degree is discussed as well as the method for its assurance and acceptable ways for its slackening. The example of the margin evaluation for the up-to-date fuel loading is given. (authors)

  5. Cluster magnetic field observations at a quasi-parallel bow shock

    Directory of Open Access Journals (Sweden)

    E. A. Lucek

    Full Text Available We present four-point Cluster magnetic field data from a quasi-parallel shock crossing which allows us to probe the three-dimensional structure of this type of shock for the first time. We find that steepened ULF waves typically have a scale larger than the spacecraft separation ( ~ 400–1000 km, while SLAMS-like magnetic field enhancements have different signatures in | B | at the four spacecraft, suggesting that they have a smaller scale size. In the latter case, however, the angular variations of B are similar, consistent with the space-craft making different trajectories through the same structure. The field enhancements have different orientations relative to a model bow shock normal, which might arise from different degrees of deceleration and deflection of the surrounding solar wind plasma. The observed rotation of the magnetic field rising from a direction approximately parallel to the model bow shock normal to a direction more perpendicular to the model normal across the field enhancement is consistent with previously published results. Successive magnetic field enhancements or ULF waves, and the leading and trailing edges of the same structure, are found to have different orientations.

    Key words. Interplanetary physics (planetary bow shocks

  6. AKARI/FIS Mapping of the ISM-Wind Bow Shock around Alpha Ori

    CERN Document Server

    Ueta, Toshiya; Yamamura, Issei; Nakada, Yoshikazu; Matsuura, Mikako; Ita, Yoshifusa; Tanabe, Toshihiko; Fukushi, Hinako; Matsunaga, Noriyuki; Mito, Hiroyuki

    2008-01-01

    We present 10' x 50' scan maps around an M supergiant Alpha Ori at 65, 90, 140 and 160 microns obtained with the AKARI Infrared Astronomy Satellite. Higher spatial resolution data with the exact analytic solution permit us to fit the de-projected shape of the stellar wind bow shock around Alpha Ori to have the stand-off distance of 4.8', position angle of 55 degrees and inclination angle of 56 degrees. The shape of the bow shock suggests that the peculiar velocity of Alpha Ori with respect to the local medium is v_* = 40 (n_H)^(-1/2), where n_H is the hydrogen nucleus density at Alpha Ori. We find that the local medium is of n_H = 1.5 to 1.9 cm^(-3) and the velocity of the local flow is at 11 km s^(-1) by using the most recent astrometric solutions for Alpha Ori under the assumption that the local medium is moving away from the Orion OB 1 association. AKARI images may also reveal a vortex ring due to instabilities on the surface of the bow shock as demonstrated by numerical models. This research exemplifies t...

  7. Magnetosheath Filamentary Structures Formed by Ion Acceleration at the Quasi-Parallel Bow Shock

    Science.gov (United States)

    Omidi, N.; Sibeck, D.; Gutynska, O.; Trattner, K. J.

    2014-01-01

    Results from 2.5-D electromagnetic hybrid simulations show the formation of field-aligned, filamentary plasma structures in the magnetosheath. They begin at the quasi-parallel bow shock and extend far into the magnetosheath. These structures exhibit anticorrelated, spatial oscillations in plasma density and ion temperature. Closer to the bow shock, magnetic field variations associated with density and temperature oscillations may also be present. Magnetosheath filamentary structures (MFS) form primarily in the quasi-parallel sheath; however, they may extend to the quasi-perpendicular magnetosheath. They occur over a wide range of solar wind Alfvénic Mach numbers and interplanetary magnetic field directions. At lower Mach numbers with lower levels of magnetosheath turbulence, MFS remain highly coherent over large distances. At higher Mach numbers, magnetosheath turbulence decreases the level of coherence. Magnetosheath filamentary structures result from localized ion acceleration at the quasi-parallel bow shock and the injection of energetic ions into the magnetosheath. The localized nature of ion acceleration is tied to the generation of fast magnetosonic waves at and upstream of the quasi-parallel shock. The increased pressure in flux tubes containing the shock accelerated ions results in the depletion of the thermal plasma in these flux tubes and the enhancement of density in flux tubes void of energetic ions. This results in the observed anticorrelation between ion temperature and plasma density.

  8. Recoil and Vibration in an Archery Bow Equipped with a Multi-Rod Stabilizer

    Directory of Open Access Journals (Sweden)

    Igor Zaniewski

    2012-01-01

    Full Text Available The aim of this research is to create a mechanical and mathematical model of a multi-rod stabilizer for the sport archery bow and to analyze its capability to damp disagreeable recoil and vibration of the bow during internal ballistic motion. The research methods are based on the Euler-Bernoulli theory of beam bending, Lagrange equations of the second kind, the Cauchy problem, and the Runge-Kutta method. A mathematical software package was used to analyze the problem. The approach to the problem of sport-bow stabilization in the vertical plane that is proposed in this paper addresses the practical needs both of applied engineering mechanics and of the sport of archery. Numerical results from computer simulation are presented in both tabular and graphical form. The common motion of the string and arrow (internal ballistic motion is accompanied by intense vibration which is caused by disruption of the static force balance at the moment of string release.

  9. Exploring Astrophysically Relevant Bow Shocks Using MIFEDS and the OMEGA Laser

    Science.gov (United States)

    Levesque, Joseph; Kuranz, Carolyn; Young, Rachel; Fiksel, Gennady; Manuel, Mario; Trantham, Matthew; Klein, Sallee; Hartigan, Patrick; Liao, Andy; Li, Chikang

    2016-10-01

    We present current experiments using the Omega Laser Facility and their magneto-inertial fusion electrical discharge system (MIFEDS) to observe the effect of magnetic pressure on bow shock dynamics in an astrophysically relevant regime. Astrophysical bow shocks are an interesting phenomenon in which a shock forms when incident supersonic flow encounters a sufficiently magnetized medium surrounding an object. The most well-known example of this phenomena is the interaction of the solar wind with the Earth's magnetic field, which creates our magnetosphere. In our experiment the magnetosphere will be emulated by a current flowing through a curved wire to create an azimuthal magnetic field. To create the analogous solar wind, lasers rear-irradiate two opposing graphite targets so the plasma outflows collide and then expand along the collision plane toward the magnetized wires. We use the UV Thomson scattering diagnostic technique to determine plasma parameters along with optical imaging and proton radiography to characterize the plasma flow and the bow shock that forms. This work is supported by the U.S. DOE, through NNSA Grants DE-NA0002956 (SSAA) and DE-NA0002719 (NLUF), by the LLE under DE-NA0001944, and by the LLNL under subcontract B614207 to DE-AC52-07NA27344.

  10. Interaction of single-pulse laser energy with bow shock in hypersonic flow

    Directory of Open Access Journals (Sweden)

    Hong Yanji

    2014-04-01

    Full Text Available Pressure sensing and schlieren imaging with high resolution and sensitivity are applied to the study of the interaction of single-pulse laser energy with bow shock at Mach 5. An Nd:YAG laser operated at 1.06 μm, 100 mJ pulse energy is used to break down the hypersonic flow in a shock tunnel. Three-dimensional Navier–Stokes equations are solved with an upwind scheme to simulate the interaction. The pressure at the stagnation point on the blunt body is measured and calculated to examine the pressure variation during the interaction. Schlieren imaging is used in conjunction with the calculated density gradients to examine the process of the interaction. The results show that the experimental pressure at the stagnation point on the blunt body and schlieren imaging fit well with the simulation. The pressure at the stagnation point on the blunt body will increase when the transmission shock approaches the blunt body and decrease with the formation of the rarefied wave. Bow shock is deformed during the interaction. Quasi-stationary waves are formed by high rate laser energy deposition to control the bow shock. The pressure and temperature at the stagnation point on the blunt body and the wave drag are reduced to 50%, 75% and 81% respectively according to the simulation. Schlieren imaging has provided important information for the investigation of the mechanism of the interaction.

  11. Astrophysical bow shocks: An analytical solution for the hypersonic blunt body problem in the intergalactic medium

    CERN Document Server

    Schulreich, Michael Mathias

    2011-01-01

    Aims: Bow shock waves are a common feature of groups and clusters of galaxies since they are generated as a result of supersonic motion of galaxies through the intergalactic medium. The goal of this work is to present an analytical solution technique for such astrophysical hypersonic blunt body problems. Methods: A method, developed by Schneider (1968, JFM, 31, 397) in the context of aeronautics, allows calculation of the galaxy's shape as long as the shape of the bow shock wave is known (so-called inverse method). In contrast to other analytical models, the solution is valid in the whole flow region (from the stagnation point up to the bow shock wings) and in particular takes into account velocity gradients along the streamlines. We compare our analytical results with two-dimensional hydrodynamical simulations carried out with an extended version of the VH-1 hydrocode which is based on the piecewise parabolic method with a Lagrangian remap. Results: It is shown that the applied method accurately predicts the...

  12. Numerical Simulation of Star Formation by the Bow Shock of the Centaurus A Jet

    CERN Document Server

    Gardner, Carl L; Scannapieco, Evan; Windhorst, Rogier A

    2016-01-01

    Recent Hubble Space Telescope (HST) observations of the extragalactic radio source Centaurus A (Cen A) display a young stellar population around the southwest tip of the inner filament 8.5 kpc from the Cen A galactic center, with ages in the range of 1-3 Myr. Crockett et al. (2012) argue that the transverse bow shock of the Cen A jet triggered this star formation as it impacted dense molecular cores of clouds in the filament. To test this hypothesis, we perform three-dimensional numerical simulations of induced star formation by the jet bow shock in the inner filament of Cen A, using a positivity preserving WENO method to solve the equations of gas dynamics with radiative cooling. We find that star clusters form inside a bow-shocked molecular cloud when the maximum initial density of the cloud is > 40 H2 molecules/cm^3. In a typical molecular cloud of mass 10^6 M_sun and diameter 200 pc, approximately 20 star clusters of mass 10^3 M_sun are formed, matching the HST images.

  13. A search for systemic mass loss in Algols with bow shocks

    CERN Document Server

    Mayer, Andreas; Jorissen, Alain

    2016-01-01

    Aims. Various studies indicate that interacting binary stars of Algol type evolve non-conservatively. However, direct detection of systemic mass loss in Algols has been scarce so far. We aim at studying the systemic mass loss in Algols by looking for the presence of infrared excesses originating from the thermal emission of dust grains, which is linked to the presence of a stellar wind. Methods. In contrast to previous studies, we make use of the fact that stellar and interstellar material is piled up at the edge of the asterosphere where the stellar wind interacts with the interstellar medium. We analyse WISE W3 $12\\,\\mu$m and WISE W4 $22\\,\\mu$m data of Algol-type binary Be and B[e] stars and the properties of their bow shocks. From the stand-off distance of the bow shock we are able to determine the mass loss rate of the binary system. Results. Although the velocities of the stars with respect to the interstellar medium are quite low, we find bow shocks to be present in two systems, namely $\\pi$ Aqr, and $\\...

  14. Corporate-Feed Multilayer Bow-Tie Antenna Array Design Using a Simple Transmission Line Model

    Directory of Open Access Journals (Sweden)

    S. Didouh

    2012-01-01

    Full Text Available A transmission line model is used to design corporate-fed multilayered bow-tie antennas arrays; the simulated antennas arrays are designed to resonate at the frequencies 2.4 GHz, 5 GHz, and 8 GHz corresponding to RFID, WIFI, and radars applications. The contribution of this paper consists of modeling multilayer bow-tie antenna array fed through an aperture using transmission line model. The transmission line model is simple and precise and allows taking into account the whole geometrical, electrical, and technological characteristics of the antennas arrays. The proposed transmission line model showed its interest in the design of different multilayered bow-tie antennas and predicted the correct resonance frequency for different applications in telecommunications. To validate the proposed transmission line model, the simulation results obtained are compared with those obtained by the method of moments. The results of simulations are presented and discussed. Using this transmission line approach, the resonant frequency, input impedance, and return loss can be determined simultaneously. The paper reports several simulation results that confirm the validity of the developed model. The obtained results are then presented and discussed.

  15. Anomalous flow deflection at planetary bow shocks in the low Alfven Mach number regime

    Science.gov (United States)

    Nishino, Masaki N.; Fujimoto, Masaki; Tai, Phan-Duc; Mukai, Toshifumi; Saito, Yoshifumi; Kuznetsova, Masha M.; Rastaetter, Lutz

    A planetary magnetosphere is an obstacle to the super-sonic solar wind and the bow shock is formed in the front-side of it. In ordinary hydro-dynamics, the flow decelerated at the shock is diverted around the obstacle symmetrically about the planet-Sun line, which is indeed observed in the magnetosheath most of the time. Here we show a case under a very low density solar wind in which duskward flow was observed in the dawnside magnetosheath of the Earth's magnetosphere. A Rankine-Hugoniot test across the bow shock shows that the magnetic effect is crucial for this "wrong flow" to appear. A full three-dimensional Magneto- Hydro-Dynamics (MHD) simulation of the situation in this previously unexplored parameter regime is also performed. It is illustrated that in addition to the "wrong flow" feature, various peculiar characteristics appear in the global picture of the MHD flow interaction with the obstacle. The magnetic effect at the bow shock should become more conspicuously around the Mercury's magnetosphere, because stronger interplanetary magnetic field and slower solar wind around the Mercury let the Alfven Mach number low. Resultant strong deformation of the magnetosphere induced by the "wrong flow" will cause more complex interaction between the solar wind and the Mercury.

  16. Formation of Cosmic Crystals in Highly-Supersaturated Silicate Vapor Produced by Planetesimal Bow Shocks

    CERN Document Server

    Miura, H; Yamamoto, T; Nakamoto, T; Yamada, J; Tsukamoto, K; Nozawa, J

    2010-01-01

    Several lines of evidence suggest that fine silicate crystals observed in primitive meteorite and interplanetary dust particles (IDPs) nucleated in a supersaturated silicate vapor followed by crystalline growth. We investigated evaporation of $\\mu$m-sized silicate particles heated by a bow shock produced by a planetesimal orbiting in the gas in the early solar nebula and condensation of crystalline silicate from the vapor thus produced. Our numerical simulation of shock-wave heating showed that these {\\mu}m-sized particles evaporated almost completely when the bow shock is strong enough to cause melting of chondrule precursor dust particles. We found that the silicate vapor cools very rapidly with expansion into the ambient unshocked nebular region; the cooling rate is estimated, for instance, to be as high as 2000 K s$^{-1}$ for a vapor heated by a bow shock associated with a planetesimal of radius 1 km. The rapid cooling of the vapor leads to nonequilibrium gas-phase condensation of dust at temperatures muc...

  17. The propagation and growth of whistler mode waves generated by electron beams in earth's bow shock

    Science.gov (United States)

    Tokar, R. L.; Gurnett, D. A.

    1985-01-01

    In this study, the propagation and growth of whistler mode waves generated by electron beams within earth's bow shock is investigated using a planar model for the bow shock and a model electron distribution function. Within the shock, the model electron distribution function possesses a field-aligned T greater than T beam that is directed toward the magnetosheath. Waves with frequencies between about 1 and 100 Hz with a wide range of wave normal angles are generated by the beam via Landau and anomalous cyclotron resonances. However, because the growth rate is small and because the wave packets traverse the shock quickly, these waves do not attain large amplitudes. Waves with frequencies between about 30 and 150 Hz with a wide range of wave normal angles are generated by the beam via the normal cyclotron resonance. The ray paths for most of these waves are directed toward the solar wind although some wave packets, due to plasma convection travel transverse to the shock normal. These wave packets grow to large amplitudes because they spend a long time in the growth region. The results suggest that whistler mode noise within the shock should increase in amplitude with increasing upstream theta sub Bn. The study provides an explanation for the origin of much of the whistler mode turbulence observed at the bow shock.

  18. Comparative Study of Electromagnetic Waves at the Bow Shocks of Venus and Earth

    Science.gov (United States)

    Wei, Hanying; Russell, Christopher T.; Strangeway, Robert J.; Schwartz, Steven J.; Zhang, Tielong

    2016-04-01

    Although the solar interactions with Venus and Earth are quite different in many ways, they both have bow shocks formed upstream of the planet where the solar wind decelerates from a super- to sub- magnetosonic flow. In the upstream foreshock region, there is abundant wave activity generated by the shock or by the back-streaming ions and electrons from the shock. In the downstream magnetosheath region, there is also abundant wave activity either locally generated by the heated electrons or ions from the shock or transported from the shock or foreshock regions by the solar wind. The magnetometers of Venus Express and Magnetospheric Multiscale missions both occasionally record 128 Hz data during their shock crossing, which allow us the search for and analyze waves at such high frequencies. We have found short-duration wave bursts around both Venus and Earth bow shocks, with certain similarities. These waves are mostly quasi-perpendicular propagating and have amplitude and occurrence rate decreasing with distance from the bow shock. In this paper we perform statistical and comparative studies on wave properties to understand their generation mechanisms and their effects to the shock or magnetosheath plasmas.

  19. Contributions to the Dart versus Arrow Debate: New Data from Holocene Projectile Points from Southeastern and Southern Brazil

    Directory of Open Access Journals (Sweden)

    Mercedes Okumura

    2015-12-01

    Full Text Available Lithic bifacial points are very common in the southern and southeastern regions of the Brazilian territory. Dated from Early to Late Holocene, these artifacts have not been studied in terms of their propulsion system. Given the characteristics of the bow and arrow compared to the atlatl and dart, there are important differences in the size and weight of arrowheads and dart points. Applying the techniques proposed by Shott (1997, Bradbury (1997, Fenenga (1953, Hughes (1998, and Hildebrandt and King (2012 to specimens recovered from eight sites dating from the early to the late Holocene, this work aims to present preliminary results to better understand the potential presence of darts and arrows in southeastern and southern Brazil. There was a variation in the results according to the application of different techniques. At least one set of points, dated from the Early Holocene, presented quite a high proportion of specimens classified as arrows, indicating the presence of points that could be used as arrowheads.

  20. Debris Flows and Floods in Southeastern Arizona from Extreme Precipitation in July 2006 - Magnitude, Frequency, and Sediment Delivery

    Science.gov (United States)

    Webb, Robert H.; Magirl, Christopher S.; Griffiths, Peter G.; Boyer, Diane E.

    2008-01-01

    From July 31 to August 1, 2006, an unusual set of atmospheric conditions aligned to produce record floods and an unprecedented number of slope failures and debris flows in southeastern Arizona. During the week leading up to the event, an upper-level low-pressure system centered over New Mexico generated widespread and locally heavy rainfall in southeastern Arizona, culminating in a series of strong, mesoscale convective systems that affected the region in the early morning hours of July 31 and August 1. Rainfall from July 27 through 30 provided sufficient antecedent moisture that the storms of July 31 through August 1 resulted in record streamflow flooding in northeastern Pima County and eastern Pinal County. The rainfall caused at least 623 slope failures in four mountain ranges, including more than 30 near Bowie Mountain in the northern Chiracahua Mountains, and 113 at the southern end of the Huachuca Mountains within and adjacent to Coronado National Memorial. In the Santa Catalina Mountains north of Tucson, 435 slope failures spawned debris flows on July 31 that, together with flood runoff, damaged structures and roads, affecting infrastructure within Tucson's urban boundary. Heavy, localized rainfall in the Galiuro Mountains on August 1, 2006, resulted in at least 45 slope failures and an unknown number of debris flows in Aravaipa Canyon. In the southern Santa Catalina Mountains, the maximum 3-day precipitation measured at a climate station for July 29-31 was 12.04 in., which has a 1,200-year recurrence interval. Other rainfall totals from late July to August 1 in southeastern Arizona also exceeded 1,000-year recurrence intervals. The storms produced floods of record along six watercourses, and these floods had recurrence intervals of 100-500 years. Repeat photography suggests that the spate of slope failures was historically unprecedented, and geologic mapping and cosmogenic dating of ancient debris-flow deposits indicate that debris flows reaching alluvial

  1. Southeastern Power Administration 2012 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-01-01

    Dear Secretary Moniz: I am pleased to submit Southeastern Power Administration’s (Southeastern) fiscal year (FY) 2012 Annual Report for your review. This report reflects our agency’s programs, accomplishments, operational, and financial activities for the 12-month period beginning October 1, 2011, and ending September 30, 2012. This past year, Southeastern marketed approximately 5.4 billion kilowatt-hours of energy to 487 wholesale customers in 10 southeastern states. Revenues from the sale of this power totaled about $263 million. With the financial assistance and support of Southeastern’s customers, funding for capitalized equipment purchases and replacements at hydroelectric facilities operated by the U.S. Army Corps of Engineers (Corps) continued in FY 2012. Currently, there are more than 214 customers participating in funding infrastructure renewal efforts of powerplants feeding the Georgia-Alabama-South Carolina, Kerr-Philpott, and Cumberland Systems. This funding, which totaled more than $71 million, provided much needed repairs and maintenance for aging projects in Southeastern’s marketing area. Drought conditions continued in the southeastern region of the United States this past year, particularly in the Savannah River Basin. Lack of rainfall strained our natural and financial resources. Power purchases for FY 2012 in the Georgia-Alabama-South Carolina System totaled approximately $29 million. About $8 million of this amount was for replacement power, which is purchased only during adverse water conditions in order to meet Southeastern’s customer contract requirements. Southeastern’s goal is to maximize the benefits of our region’s water resources. Competing uses of these resources will present another challenging year for Southeastern’s employees. With the cooperation and communication among the Department of Energy (DOE), preference customers, and Corps, I am certain Southeastern is positioned to meet these challenges in the future. We

  2. Southeastern Power Administration 2011 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-12-31

    Dear Secretary Chu: I am pleased to submit Southeastern Power Administration’s (Southeastern) fiscal year (FY) 2011 Annual Report for your review. This report reflects our agency’s programs, accomplishments, operational, and financial activities for the 12-month period beginning October 1, 2010, and ending September 31, 2011. This past year, Southeastern marketed approximately 6.2 billion kilowatt-hours of energy to 489 wholesale customers in 10 southeastern states. Revenues from the sale of this power totaled more than $264 million. With the financial assistance and support of Southeastern’s customers, funding for capitalized equipment purchases and replacements at hydroelectric facilities operated by the U.S. Army Corps of Engineers (Corps) continued in FY 2011. This funding, which totaled more than $45 million, provided much needed repairs and maintenance for aging projects in Southeastern’s marketing area. Currently, there are more than 214 customers participating in the funding efforts in the Georgia-Alabama-South Carolina, Kerr-Philpott, and Cumberland Systems of projects. Drought conditions continued in the southeastern region of the United States this past year, particularly in the Savannah River Basin. Lack of rain placed strains on our natural and financial resources. Power purchases for FY 2011 totaled approximately $38 million. About $9 million of this amount was for replacement power, which is purchased only during adverse water conditions in order to meet Southeastern’s customer contract requirements. Southeastern’s goal is to maximize the benefits of our region’s water resources. Competing uses of these resources will present another challenging year for Southeastern’s employees. With the cooperation and communication among the Department of Energy (DOE), preference customers, and Corps, I am certain Southeastern is positioned to meet these challenges in the future. We are committed to providing reliable hydroelectric power to

  3. Landforms of High Mountains

    Directory of Open Access Journals (Sweden)

    Derek A. McDougall

    2016-05-01

    Full Text Available Reviewed: Landforms of High Mountains. By Alexander Stahr and Ewald Langenscheidt. Heidelberg, Germany: Springer, 2015. viii + 158 pp. US$ 129.99. Also available as an e-book. ISBN 978-3-642-53714-1.

  4. Rocky Mountain spotted fever

    Science.gov (United States)

    ... Mountain spotted fever is caused by the bacteria Rickettsia rickettsii (R. Rickettsii) , which is carried by ticks. ... Saunders; 2014:chap 212. Walker DH, Blaton LS. Rickettsia rickettsii and other spotted fever group rickettsiae (Rocky ...

  5. Ephemeroptera, Plecoptera and Trichoptera assemblages in litter in a mountain stream of the Atlantic Rainforest from Southeastern Brazil Comunidades de Ephemeroptera, Plecoptera e Trichoptera em folhiço de um riacho de montanha da Mata Atlântica do Sudeste do Brasil

    Directory of Open Access Journals (Sweden)

    Vera L. Crisci-Bispo

    2007-01-01

    Full Text Available The study of Ephemeroptera, Plecoptera and Trichoptera associated with litter in southeastern Brazil streams aimed to answer the following questions: 1 Does richness and composition of EPT fauna differ between riffle and pool mesohabitats despite being associated to the same substratum, litter? 2 Does the similarity of the EPT fauna between both mesohabitats change with time? 3 Does the EPT functional feeding structure differ between both mesohabitats (riffles-pools? In order to answer these questions, monthly collections, from November 1999 to June 2000, were done in Ribeirão (Stream Bocaina with a D-net (10 litter patches in riffles and 10 in pools. The EPT fauna at Ribeirão Bocaina was more diversified and more abundant in the litter in riffles than in the litter in pools, although, when richness was standardized for the same number of individuals it became similar in both conditions. EPT fauna was very different between both mesohabitats in terms of faunal composition as well as in terms of function. Probably it was due to differences in water speed, in the time of litter residence and in the concentration of dissolved oxygen between both mesohabitats.A fauna de Ephemeroptera, Plecoptera e Trichoptera associadas ao folhiço em um riacho do sudeste do Brasil foi estudada com o objetivo de responder às seguintes questões: 1 A riqueza e a composição faunística de EPT difere entre os dois mesohabitats (corredeira-remanso mesmo quando associadas ao mesmo substrato, folhiço? 2 A similaridade da fauna de EPT entre os dois mesohabitas muda temporalmente? 3 A estrutura funcional de EPT difere entre os dois mesohabitats (corredeira-remanso? Para responder essas questões, coletas mensais, de novembro de 1999 a junho de 2000, foram feitas no Ribeirão Bocaina com rede D (10 acúmulos de folhas em remanso e 10 em corredeira. A fauna de EPT do Ribeirão Bocaina foi mais diversificada e mais abundante no folhiço em corredeira do que no folhi

  6. Synoptic Variability of Extreme Snowfall in the St. Elias Mountains, Yukon, Canada

    OpenAIRE

    Andin, Caroline

    2015-01-01

    Glaciers of southwestern Yukon (Canada) and southeastern Alaska (USA) are presently experiencing high rates of annual mass loss. These high melt rates have mainly been investigated with respect to regional temperature trends, but comparatively little is known about how climate variations regulate snow accumulation on these glaciers. This study examines the synoptic weather patterns and air flow trajectories associated with extreme snowfall events in the central St. Elias Mountains (Yukon). Th...

  7. Diurnal variation of mountain waves

    Directory of Open Access Journals (Sweden)

    R. M. Worthington

    2006-11-01

    Full Text Available Mountain waves could be modified as the boundary layer varies between stable and convective. However case studies show mountain waves day and night, and above e.g. convective rolls with precipitation lines over mountains. VHF radar measurements of vertical wind (1990–2006 confirm a seasonal variation of mountain-wave amplitude, yet there is little diurnal variation of amplitude. Mountain-wave azimuth shows possible diurnal variation compared to wind rotation across the boundary layer.

  8. Mountain goat abundance and population trends in the Olympic Mountains, northwestern Washington, 2016

    Science.gov (United States)

    Jenkins, Kurt J.; Happe, Patricia J.; Beirne, Katherine F.; Baccus, William T.

    2016-11-30

    Executive SummaryWe estimated abundance and trends of non-native mountain goats (Oreamnos americanus) in the Olympic Mountains of northwestern Washington, based on aerial surveys conducted during July 13–24, 2016. The surveys produced the seventh population estimate since the first formal aerial surveys were conducted in 1983. This was the second population estimate since we adjusted survey area boundaries and adopted new estimation procedures in 2011. Before 2011, surveys encompassed all areas free of glacial ice at elevations above 1,520 meters (m), but in 2011 we expanded survey unit boundaries to include suitable mountain goat habitats at elevations between 1,425 and 1,520 m. In 2011, we also began applying a sightability correction model allowing us to estimate undercounting bias associated with aerial surveys and to adjust survey results accordingly. The 2016 surveys were carried out by National Park Service (NPS) personnel in Olympic National Park and by Washington Department of Fish and Wildlife (WDFW) biologists in Olympic National Forest and in the southeastern part of Olympic National Park. We surveyed a total of 59 survey units, comprising 55 percent of the 60,218-hectare survey area. We estimated a mountain goat population of 623 ±43 (standard error, SE). Based on this level of estimation uncertainty, the 95-percent confidence interval ranged from 561 to 741 mountain goats at the time of the survey.We examined the rate of increase of the mountain goat population by comparing the current population estimate to previous estimates from 2004 and 2011. Because aerial survey boundaries changed between 2004 and 2016, we recomputed population estimates for 2011 and 2016 surveys based on the revised survey boundaries as well as the previously defined boundaries so that estimates were directly comparable across years. Additionally, because the Mount Washington survey unit was not surveyed in 2011, we used results from an independent survey of the Mount

  9. Effect of bow-type initial imperfection on the buckling load and mass of graphite-epoxy blade-stiffened panels

    Science.gov (United States)

    Stroud, W. J.; Anderson, M. S.; Hennessy, K. W.

    1977-01-01

    A structural synthesis computer code which accounts for first order effects of an initial bow and which can be used for sizing stiffened composite panels having an arbitrary cross section is used to study graphite blade-stiffened panels. The effect of a small initial bow on both the load carrying ability of panels and on the mass of panels designed to carry a specified load is examined. Large reductions in the buckling load caused by a small initial bow emphasize the need for considering a bow when a panel is designed.

  10. YUCCA MOUNTAIN SITE DESCRIPTION

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Simmons

    2004-04-16

    The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

  11. Social-value maps for Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests, Colorado and Wyoming

    Science.gov (United States)

    Ancona, Zachary H.; Semmens, Darius J.; Sherrouse, Benson C.

    2016-03-25

    Executive SummaryThe continued pressures of population growth on the life-sustaining, economic, and cultural ecosystem services provided by our national forests, particularly those located near rapidly growing urban areas, present ongoing challenges to forest managers. Achieving an effective assessment of these ecosystem services includes a proper accounting of the ecological, economic, and social values attributable to them. However, assessments of ecosystem goods and services notably lack information describing the spatial distribution and relative intensity of social values—the perceived, nonmarket values derived particularly from cultural ecosystem services. A geographic information system (GIS) tool developed to fill this need, Social Values for Ecosystem Services (SolVES; http://solves.cr.usgs.gov), now provides the capability to generate social-value maps at a range of spatial scales. This report presents some of the methods behind SolVES, procedures needed to apply the tool, the first formal map products resulting from its application at a regional scale, and a discussion of the management implications associated with this type of information.In this study, we use SolVES to identify the location and relative intensity of social values as derived from survey responses gathered from residents living in counties adjacent to Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests. The results, presented as a series of social-value maps, represent the first publicly available spatial data on social-value intensity for the southern Rocky Mountain region. Our analysis identified high-value areas for social values including aesthetic, biodiversity, and life sustaining within wilderness areas. Other values, like recreation, show high-value areas both within wilderness and throughout the general forest areas, which can be attributed to people using the forests for a diverse set of recreational activities. The economic social-value type was lower

  12. Post-Gondwanan continental sedimentaiton, Limpopo region, southeastern Africa

    Science.gov (United States)

    Botha, G. A.; De Wit, M. C. J.

    1996-08-01

    The post-Karoo age sedimentary succession known formerly as the Malvernia Formation, is currently termed the Malonga Formation, 'Formaçao de Sena', 'Formaçao de Singuédeze/Elefantes' and Gona-re-Zhou Plateau Beds in the Limpopo Basin region where South Africa, Mozambique and Zimbabwe have common borders. These rocks represent continental, taphrogenic sedimentation on the eastern margin of the emergent African continent after the breakup of Gondwana. The wide occurrence of this system along the northern Lebombo mountains and within the tectonically active Limpopo and Zambezi valleys, suggests the existence of a peidmont landsurface comprising coalesced alluvial fans and major fluvial channel/floodplain systems close to the continental margin during the Late Mesozoic to Early Cainozoic era. Sedimentation followed the long period of eustatic uplift associated with Karoo vulcanicity and the extensional tectonics and rifting along the continental margin and within the proto-Limpopo and Zambezi valleys. The Malonga Formation exposed near Pafuri in the extreme NW of South Africa shows an eastward lithological change from homogeneous, poorly-sorted, thinly-bedded sandstones and conglomerates, deposited by sheetflood action, to a sequence of fining-upward units comprising clast-supported pebble to boulder grade conglomerate and overlying planar bedded silt and sand, deposited in fluvial channel and floodplain environments. The homogeneous, silty succession exposed in the Olifants River valley, east of the Lebombo mountains in Mozambique, possibly represents the distal reaches of this system. Calcareous palaeosols developed within the sedimentary units suggest periodic geomorphic stability on the broad alluvial plain. Further north in southeastern Zimbabwe, laterally continuous depositional units comprising thinly-bedded, poorly-sorted, matrix-supported conglomerate, interbedded with very coarse-grained sandstone, is consistent with deposition on an alluvial fan complex

  13. Macroscopic polarization and bowing constant of Al{sub x}Ga{sub 1−x}N

    Energy Technology Data Exchange (ETDEWEB)

    Pansari, A.; Gedam, V.; Sahoo, B.K., E-mail: bksahoo.phy@nitrr.ac.in

    2015-01-01

    In this work, we have theoretically investigated the effect of macroscopic polarization (sum of spontaneous and piezoelectric polarization) on various thermal parameters of Al{sub x}Ga{sub 1−x}N alloy. The macroscopic polarization contributes to the effective elastic constant of Al{sub x}Ga{sub 1−x}N alloy. This contribution modifies the phonon group velocity, Debye temperature and Debye frequency of the alloy. The revised values of these thermal parameters have been estimated as a function of Al composition. Our calculation shows that these thermal parameters are enhanced and vary non-linearly with Al composition i.e., they show bowing. The cause of this bowing is the non linear dependence of spontaneous and piezoelectric polarization on Al composition. The bowing constant of above thermal parameters (with and without polarization) has been theoretically predicted by method of best fit. The results show that polarization mechanism not only enhances the parameters but also contribute significantly to bowing constant. The macroscopic polarization contributes around 48% to bowing constant of above thermal parameters. The obtained result will be useful for simulation of nitride optoelectronics devices to predict the effect of polarization mechanism on thermoelectric properties of Al{sub x}Ga{sub 1−x}N alloy.

  14. Effect of an isotropic outflow from the Galactic centre on the bow-shock evolution along the orbit

    CERN Document Server

    Zajacek, Michal; Karas, Vladimir; Kunneriath, Devaky; Shahzamanian, Banafsheh; Sabha, Nadeen; Muzic, Koraljka; Valencia-Schneider, Monica

    2015-01-01

    Motivated by the observations of several infrared-excess bow-shock sources and proplyd-like objects near the Galactic centre, we analyse the effect of a potential outflow from the centre on bow shock properties. We show that due to the non-negligible isotropic central outflow the bow-shock evolution along the orbit becomes asymmetric between the pre-peribothron and post-peribothron phases. This is demonstrated by the calculation of the bow-shock size evolution, the velocity along the shocked layer, the surface density of the bow-shock, and by emission-measure maps close to the peribothron passage. Within the ambient velocity range of $\\lesssim 2000\\,{\\rm km\\, s^{-1}}$ the asymmetry is profound and the changes are considerable for different outflow velocities. As a case study we perform model calculations for the Dusty S-cluster Object (DSO/G2) as a potential young stellar object that is currently being monitored and has passed the pericentre at $\\sim 2000$ Schwarzschild radii from the supermassive black hole ...

  15. Discovering Massive Runaway Stars with Infrared Bow Shock Nebulae: Four OB Stars Found in WISE

    Science.gov (United States)

    Wernke, Heather N.; Kobulnicky, Henry A.; Dale, Daniel A.; Povich, Matthew S.; Andrews, Julian E.; Chick, William T.; Munari, Stephan; Olivier, Grace M.; Schurhammer, Danielle; Sorber, Rebecca L.

    2016-01-01

    Supernovae, pulsars, and gamma-ray bursts are examples of the result of the death of massive (late-O and early-B type) stars. Determining stellar mass loss rates can help us predict the type of death the star will endure. We focus on stars that are located at the center of an infrared bow shock nebula, indicating that the star was flung from its birthplace at supersonic speed. Observing these massive, high-velocity, runaway stars with bow shock nebulae to determine their spectral type will help in the measurements of their stellar mass loss rates. The spectra of four OB stars driving bow shock candidates are presented. These four candidates were found by searching through the Wide-field Infrared Survey Explorer (WISE) All-Sky Data Release and were the most visible in the WISE 21µm band. The spectrum for each star was obtained with the Longslit Spectrograph at the Wyoming Infrared Observatory (WIRO). The spectral types of G077.3617+01.16 (HD 229159), G079.8219+00.096 ([CPR2002]A10), G092.7265+00.18, and G076.0752-02.2044 (TYC 2697-1046-1) were found to be B1.0I, O9.0V, B0.0V, and B0.0V respectively. As predicted, the candidates are all either late-O or early-B type stars. Now that the spectral types of these stars are known, further analysis can be done to determine the velocities, temperatures, masses, and stellar mass loss rates.This work is supported by the National Science Foundation under grants AST-1063146 (REU), AST-1411851 (RUI), and AST-1412845.

  16. Study of the Combination of FTA, ETA and Bow-tie Evaluation Methods and Its Application%基于FTA、ETA、Bow-tie三种评价方法的结合及其应用研究

    Institute of Scientific and Technical Information of China (English)

    李婷婷; 赵姚峰

    2013-01-01

    在FTA与ETA分析方法结合的基础上引入蝴蝶结分析法(Bow-tie法)能很好的克服FTA和ETA的局限性。本文将ETA、FTA及Bow-tie法进行结合并将其应用到燃气管道泄漏的安全评价及分析中。%Introducing Bow-tie analytical method into the combination of FTA and ETA can well overcome the limitation of FTA and ETA. This article combines ETA, FTA and Bon-tie method and apply it into the safety evaluation and analysis of gas pipeline leakage.

  17. Electron - whistler interaction at the Earth`s bow shock: 1. Whistler instability

    Energy Technology Data Exchange (ETDEWEB)

    Veltri, P.; Zimbardo, G. [Universita della Calabria, Cosenza (Italy)

    1993-08-01

    The authors model the interaction of whistler waves with the quasi-perpendicular bow shock observed on Nov 7, 1977. Using a Monte Carlo technique they are able to construct the resulting electron distribution function. This distribution function is asymmetric, and includes a loss cone which the data supports. This distribution function asymmetry is able to drive instabilites which couple to generate additional whister energy. A significant amount of the whistler energy is observed to originate from the region where the loss cone is observed.

  18. Primary task-specific bowing tremor: an entity of its own?

    Science.gov (United States)

    Lee, André; Altenmüller, Eckart

    2012-12-01

    A professional violinist in his early 60s, playing in a prestigious German orchestra for more than 20 years, presented to our institute because of a task-induced tremor in his right arm when playing the violin. We describe the phenomenology of this tremor and its treatment options and compare it to findings in primary writing tremor (PWT). We then discuss whether primary bowing tremor is an entity of its own (similar to PWT) and propose hypotheses that would derive from such a definition.

  19. Printed Modified Bow-Tie Dipole Antenna for DVB/WLAN Applications

    Directory of Open Access Journals (Sweden)

    Ching-Chih Hung

    2013-01-01

    Full Text Available A printed modified bow-tie dipole antenna which consists of asymmetric-feed and inserted slots is presented to apply to the DVB and WLAN systems. This antenna combines omnidirectional radiation pattern, broad bandwidth, and band rejection in an easy way to fabricate. Experimental results of the constructed prototype indicate that the VSWR 2.5 : 1 bandwidths achieve 166.7%, 28.57%, and 23.63% at 660 MHz, 2450 MHz, and 5500 MHz, respectively.

  20. Heavy Solar Wind Ion Dynamics at and Downstream from the Bow Shock

    Science.gov (United States)

    Dougherty, Virginia M.

    1997-01-01

    This is a contract under the NASA Supporting Research and Technology Program for the analysis and interpretation of the scientific data from the Plasma Composition Experiment on the International Sun Earth Explorer 1 (ISEE-1) spacecraft and the Fast Plasma Experiment on the ISEE-1 and -2 spacecraft. These combined data sets will be used in a comprehensive study of the heavy solar wind ion dynamics at and downstream from the Earth's bow shock. The report summarizes activities during the above period and outlines expected activities during the forthcoming quarter.

  1. Asymptotic Steady State Solution to a Bow Shock with an Infinite Mach Number

    CERN Document Server

    Yalinewich, Almog

    2015-01-01

    The problem of a cold gas flowing past a stationary object is considered. It is shown that at large distances from the obstacle the shock front forms a parabolic solid of revolution. The interior of the shock front is obtained by solution of the hydrodynamic equations in parabolic coordinates. The results are verified with a hydrodynamic simulation. The drag force and expected spectra are calculated for such shock, both in case of an optically thin and thick media. Finally, relations to astrophysical bow shocks and other analytic works on oblique shocks are discussed.

  2. Homotopy method for inverse design of the bulbous bow of a container ship

    Science.gov (United States)

    Huang, Yu-jia; Feng, Bai-wei; Hou, Guo-xiang; Gao, Liang; Xiao, Mi

    2017-03-01

    The homotopy method is utilized in the present inverse hull design problem to minimize the wave-making coefficient of a 1300 TEU container ship with a bulbous bow. Moreover, in order to improve the computational efficiency of the algorithm, a properly smooth function is employed to update the homotopy parameter during iteration. Numerical results show that the homotopy method has been successfully applied in the inverse design of the ship hull. This method has an advantage of high performance on convergence and it is credible and valuable for engineering practice.

  3. Bow-tie optical antenna probes for single-emitter scanning near-field optical microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, Javad N [Nano-Optics Group, National Center of Competence for Research in Nanoscale Science, Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Eisler, Hans-Juergen [Nano-Optics Group, National Center of Competence for Research in Nanoscale Science, Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Pohl, Dieter W [Nano-Optics Group, National Center of Competence for Research in Nanoscale Science, Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Pavius, Michael [Center of MicroNanoTechnology (CMI), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Flueckiger, Philippe [Center of MicroNanoTechnology (CMI), Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Gasser, Philippe [EMPA, Swiss Federal Laboratories for Materials Testing and Research, Electronics/Metrology Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Hecht, Bert [Nano-Optics Group, National Center of Competence for Research in Nanoscale Science, Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

    2007-03-28

    A method for the fabrication of bow-tie optical antennas at the apex of pyramidal Si{sub 3}N{sub 4} atomic force microscopy tips is described. We demonstrate that these novel optical probes are capable of sub-wavelength imaging of single quantum dots at room temperature. The enhanced and confined optical near-field at the antenna feed gap leads to locally enhanced photoluminescence (PL) of single quantum dots. Photoluminescence quenching due to the proximity of metal is found to be insignificant. The method holds promise for single quantum emitter imaging and spectroscopy at spatial resolution limited by the engineered antenna gap width exclusively.

  4. Mapping the Structure of Directed Networks: Beyond the "Bow-tie" Diagram

    CERN Document Server

    Timár, G; Dorogovtsev, S N; Mendes, J F F

    2016-01-01

    We reveal a hierarchical organization of finite directed components---tendrils---around the giant components represented by the celebrated "bow-tie" diagram for directed networks. We develop an efficient algorithm to find tendril layers. It is used together with the message passing technique, generalized to directed graphs, to find the structure and attack tolerance of complex networks, such as the World Wide Web, the neural network of Caenorhabditis elegans, and others. We introduce a generalized susceptibility characterizing the response of directed networks to damage.

  5. Southeastern Power Administration 2008 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-12-29

    Dear Secretary Chu: I am pleased to submit Southeastern Power Administration’s (Southeastern’s) fiscal year (FY) 2008 Annual Report for your review. The information included in this document reflects our agency’s programs, accomplishments, operational and financial activities for the 12-month period beginning October 1, 2007 and ending September 30, 2008. Southeastern marketed more than 4.5 billion kilowatt-hours of energy to 491 wholesale customers in ten southeastern states this past year. Revenues from the sale of this power totaled approximately $263 million. Drought conditions persisted in the southeastern region of the United States during FY 2008 placing strains on our natural and financial resources. Power purchases for FY 2008 totaled $91 million. Approximately $44 million of this amount was for replacement power which is paid only during adverse water conditions in order to meet our customers’ contract requirements. With the continued financial assistance and support of our Federal power customers, funding for capitalized equipment purchases and replacements at U.S. Army Corps of Engineers’ (Corps) hydroelectric projects provided much needed repairs and maintenance for these aging facilities. Southeastern’s cyber and physical security programs continued to be reviewed and updated to meet Department of Energy (DOE), Homeland Security, and North American Electric Reliability Corporation (NERC) standards and requirements. In the coming year, Southeastern will continue open communication and cooperation with DOE, the Federal power customers, and the Corps to maximize the benefits of our region’s water resources. Although competing uses of water and the prolonged drought conditions will present another challenging year for our agency, Southeastern’s employees will meet these challenges and continue to provide reliable hydroelectric power to the people in the southeast. Sincerely, Kenneth E.Legg Administrator

  6. Comparison of theory with atomic oxygen 130.4 nm radiation data from the Bow Shock ultraviolet 2 rocket flight

    Science.gov (United States)

    Levin, Deborah A.; Candler, Graham V.; Collins, Robert J.; Howlett, Carl L.; Espy, Patrick; Whiting, Ellis; Park, Chul

    1993-01-01

    Comparison is made between the results obtained from a state-of-the-art flow and radiative model and bow shock vacuum ultraviolet (VUV) data obtained the recent Bow Shock 2 Flight Experiment. An extensive data set was obtained from onboard rocket measurements at a reentry speed of 5 km/sec between the altitudes of approximately 65-85 km. A description of the NO photoionization cell used, the data, and the interpretation of the data will be presented. The primary purpose of the analyses is to assess the utility of the data and to propose a radiation model appropriate to the flight conditions of Bow Shock 2. Theoretical predictions based on flow modeling discussed in earlier work and a new radiation model are compared with data.

  7. Archery by the Apaches – implications of using the bow and arrow in hunter-gatherer communities

    Directory of Open Access Journals (Sweden)

    Žiga Šmit

    2016-12-01

    Full Text Available This review focuses on the technical and social details of production, training, and use of archery equipment by a Native American tribe, the Apaches. The study aims to understand the use of the bow in the Mesolithic and Early and Middle Neolithic societies of the Old World. The paper further describes arrow ballistics. An arrow and bow with similar dimensions and materials to those used by the Apaches was reconstructed and used in ballistic experiments. Shooting and the subsequent model calculation showed that the effective range of arrows made of reed and projected by a bow of medium strength (16–18kg was not more than approx. 20m. Due to the initial flat part of the ballistic trajectory, such arrows were quite efficient in close-range contests. Within the model calculation, a regression procedure was introduced to determine the arrow air-drag parameters from an ensemble of shots.

  8. Finite-element procedure for calculating the three-dimensional inelastic bowing of fuel rods (AWBA development program)

    Energy Technology Data Exchange (ETDEWEB)

    Martin, S E

    1982-05-01

    An incremental finite element procedure is developed for calculating the in-pile lateral bowing of nuclear fuel rods. The fuel rod is modeled as a viscoelastic beam whose material properties are derived as perturbations of the results of an axisymmetric stress analysis of the fuel rod. The effects which are taken into account in calculating the rod's lateral bowing include: (a) lateral, axial, and rotational motions and forces at the rod supports, (b) transverse gradients of temperature, fast-neutron flux, and fissioning rate, and (c) cladding circumferential wall thickness variation. The procedure developed in this report could be used to form the basis for a computer program to calculate the time-dependent bowing as a function of the fuel rod's operational and environmental history.

  9. A new technique to characterize CT scanner bow-tie filter attenuation and applications in human cadaver dosimetry simulations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinhua; Shi, Jim Q.; Zhang, Da; Singh, Sarabjeet; Padole, Atul; Otrakji, Alexi; Kalra, Mannudeep K.; Liu, Bob, E-mail: bliu7@mgh.harvard.edu [Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Xu, X. George [Nuclear Engineering Program, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2015-11-15

    Purpose: To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. Methods: A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field-of-view. The sampling time was as short as 0.24 ms. To measure the body bow-tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x-ray tube was parked at the 12 o’clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow-tie in the beam path. Each readout signal was corrected for the detector background offset and signal-level related nonlinear gain, and the ratio of the two exposures gave the bow-tie attenuation. The results were used in the GEANT4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x-ray tube starting angles. Results: Absolute attenuation was measured with the body bow-tie scanned at 80–140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively. Conclusions: The described method allows fast and accurate bow-tie filter characterization.

  10. Optical hydrogen absorption consistent with a thin bow shock leading the hot Jupiter HD 189733b

    CERN Document Server

    Cauley, P Wilson; Jensen, Adam G; Barman, Travis; Endl, Michael; Cochran, William D

    2015-01-01

    Bow shocks are ubiquitous astrophysical phenomena resulting from the supersonic passage of an object through a gas. Recently, pre-transit absorption in UV metal transitions of the hot Jupiter exoplanets HD 189733b and WASP12-b have been interpreted as being caused by material compressed in a planetary bow shock. Here we present a robust detection of a time-resolved pre-transit, as well as in-transit, absorption signature around the hot Jupiter exoplanet HD 189733b using high spectral resolution observations of several hydrogen Balmer lines. The line shape of the pre-transit feature and the shape of the time series absorption provide the strongest constraints on the morphology and physical characteristics of extended structures around an exoplanet. The in-transit measurements confirm the previous exospheric H-alpha detection although the absorption depth measured here is ~50% lower. The pre-transit absorption feature occurs 125 minutes before the predicted optical transit, a projected linear distance from the ...

  11. A hydrodynamic optimization design methodology for a ship bulbous bow under multiple operating conditions

    Directory of Open Access Journals (Sweden)

    Yu Lu

    2016-01-01

    Full Text Available The main objective of this article is to describe an innovative methodology for the hydrodynamic optimization of a ship bulbous bow which considers multiple operating conditions. The proposed method is more practical and effective than the traditional optimization process, which is only based on contractually specified design condition. Parametric form approaches are adopted by employing an F-spline curve in order to generate variants of the hull bulbous bow forms using form design parameters modified, resulting in an optimization system based on improved genetic algorithms. The Rankine source panel method is used for the hydrodynamic evaluation, wherein non-linear free surface conditions and the trim and sinkage of the ship are taken into consideration. The validity and effectiveness of the proposed methodology for a large container ship is investigated by comparing the computational results with experimental data, which demonstrates that the proposed methodology can engage well in the automation process and improve hydrodynamic performance during actual ship design practices.

  12. Modeling plasma glow discharges in Air near a Mach 3 bow shock with KRONOS

    Science.gov (United States)

    Rassou, Sebastien; Labaune, Julien; Packan, Denis; Elias, Paul-Quentin

    2016-09-01

    In this work, plasma glow discharge in Air is modeled near a Mach 3 bow shock. Numerical simulations are performed using the coupling KRONOS which have been developed at ONERA. The flow field is modeled using the code CFD: CEDRE from ONERA and the electrical and plasma part by the EDF open-source code CODE_SATURNE. The plasma kinetic modeling consists on a two-term Boltzmann equation solver and a chemical reaction solver depending of the electric field. The coupling KRONOS is fully parallelized and run on ONERA supercomputers. The shock wave is formed by the propagation of a supersonic flow (M = 3) through a truncated conical model mounted with a central spike. Depending on the spike's voltage value, corona, glow or arc regime could be obtained in a steady flow. The parameters for the supersonic flow and the spike configurations are chosen to be in glow discharge regime and to reproduce the experimental setup. In our simulations, 12 species and 80 reactions (ionization, electronic or vibrational excitation, attachment etc ...) are considered to properly model the glow discharge and the afterglow. In a stationary flow, glow discharge is observed only at the upstream of the shock wave near the high voltage spike. Behind the bow shock, in the afterglow, negative ions are provided by electrons attachment with O2. The negative ions flow convection ensures the electrical conduction and the establishment of the glow discharge.

  13. The excitation conditions of magnetospheric convection by the electric current generated in the bow shock

    Science.gov (United States)

    Sedykh, P. A.; Ponomarev, E. A.

    The solar wind undergoes the greatest change of its parameters during the passage through the bow shock front Its density in this case increases by the factor of four and gas and magnetic pressure increase more than by an order of magnitude In this paper we re-examine the consequences of the fact of electric current generation at the bow shock front that we considered at an earlier date and the dependence of the direction of this current on the sign of IMF Bz-component The first consequence is the closure of the aforementioned current through the magnetosphere It was found that this process is a two-stage one Initially the electric field penetrates and establishes in the medium a new convective regime After that depending on the degree of flow inhomogeneity a plasma density distribution can be established which corresponds to the electric current equal to the external current The new steady state to which the new convection velocity field and the new plasma pressure field correspond is established within the time of the order of the transit time taken by the magnetosonic wave to propagate through the entire system Also a linkage between the power dissipated inside the magnetosphere and the parameters of plasma convection existing therein is shown

  14. The properties of bow-shock sources at the Galactic Center

    CERN Document Server

    Sanchez-Bermudez, J; Alberdi, A; Muzic, K; Hummel, C A; Pott, J -U

    2014-01-01

    There are an enigmatic population of massive stars around the Galactic Center (GC) that were formed some Ma ago. A fraction of these stars has been found to orbit the supermassive black hole, SgrA*, in a projected clockwise disk, which suggests that they were formed in a formerly existing dense disk around SgrA*. We focus on the extended, near-infrared (NIR) sources IRS1W, IRS5, IRS10W, and IRS21 that have been suggested to be young, massive stars that form bow-shocks through their interaction with the ISM. Their nature has impeded accurate determination of their orbital parameters. We aim at establishing their nature and kinematics to test whether they form part of the clockwise disk. We performed NIR multi-wavelength imaging using adaptive optics (AO) and sparse aperture masking (SAM). We introduce a new method for self-calibration of the SAM PSF in dense stellar fields. The emission mechanism, morphology and kinematics of the targets were examined via 3D bow-shock models. We confirm previous findings that ...

  15. Reconstructing the Guitar: Blowing Bubbles with a Pulsar Bow Shock Back Flow

    CERN Document Server

    van Kerkwijk, Marten H

    2008-01-01

    The Guitar Nebula is an H-alpha nebula produced by the interaction of the relativistic wind of a very fast pulsar, PSR B2224+65, with the interstellar medium. It consists of a ram-pressure confined bow shock near its head and a series of semi-circular bubbles further behind, the two largest of which form the body of the Guitar. We present a scenario in which this peculiar morphology is due to instabilities in the back flow from the pulsar bow shock. From simulations, these back flows appear similar to jets and their kinetic energy is a large fraction of the total energy in the pulsar's relativistic wind. We suggest that, like jets, these flows become unstable some distance down-stream, leading to rapid dissipation of the kinetic energy into heat, and the formation of an expanding bubble. We show that in this scenario the sizes, velocities, and surface brightnesses of the bubbles depend mostly on observables, and that they match roughly what is seen for the Guitar. Similar instabilities may account for feature...

  16. Numerical modeling of a glow discharge through a supersonic bow shock in air

    Science.gov (United States)

    Rassou, S.; Packan, D.; Elias, P.-Q.; Tholin, F.; Chemartin, L.; Labaune, J.

    2017-03-01

    The interaction between a glow discharge and the bow shock of a Mach 3 air flow around a truncated conical model with a central spike is modeled, and comparison is made with prior experimental results. The KRONOS workflow for plasma modeling in flow fields, which has recently been developed at ONERA, was used for the modeling. Based on the quasi-neutral approximation, it couples hypersonic and reactive flow fields with electron chemistry, including the effect of non-Maxwellian electron energy distribution function. The model used for the discharge involves 12 species and 82 reactions, including ionization, electronic and vibrational excitation, and attachment. The simulations reproduce the main features of the discharge observed experimentally well, in particular, the very recognizable topology of the discharge. It was found from the simulations that behind the bow shock, in the afterglow, the negative ion flow ensures the electrical conduction and the establishment of the glow discharge. The influence of kinetic rates on the voltage-current characteristics is discussed.

  17. Diversity of sponges (Porifera) from cryptic habitats on the Belize barrier reef near Carrie Bow Cay.

    Science.gov (United States)

    Rützler, Klaus; Piantoni, Carla; Van Soest, Rob W M; Díaz, M Cristina

    2014-05-29

    The Caribbean barrier reef near Carrie Bow Cay, Belize, has been a focus of Smithsonian Institution (Washington) reef and mangrove investigations since the early 1970s. Systematics and biology of sponges (Porifera) were addressed by several researchers but none of the studies dealt with cryptic habitats, such as the shaded undersides of coral rubble, reef crevices, and caves, although a high species diversity was recognized and samples were taken for future reference and study. This paper is the result of processing samples taken between 1972 and 2012. In all, 122 species were identified, 14 of them new (including one new genus). The new species are Tetralophophora (new genus) mesoamericana, Geodia cribrata, Placospongia caribica, Prosuberites carriebowensis, Timea diplasterina, Timea oxyasterina, Rhaphidhistia belizensis, Wigginsia curlewensis, Phorbas aurantiacus, Myrmekioderma laminatum, Niphates arenata, Siphonodictyon occultum, Xestospongia purpurea, and Aplysina sciophila. We determined that about 75 of the 122 cryptic sponge species studied (61%) are exclusive members of the sciophilic community, 47 (39 %) occur in both, light-exposed and shaded or dark habitats. Since we estimate the previously known sponge population of Carrie Bow reefs and mangroves at about 200 species, the cryptic fauna makes up 38 % of total diversity.

  18. Compound semiconductor alloys: From atomic-scale structure to bandgap bowing

    Energy Technology Data Exchange (ETDEWEB)

    Schnohr, C. S., E-mail: c.schnohr@uni-jena.de [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

    2015-09-15

    Compound semiconductor alloys such as In{sub x}Ga{sub 1−x}As, GaAs{sub x}P{sub 1−x}, or CuIn{sub x}Ga{sub 1−x}Se{sub 2} are increasingly employed in numerous electronic, optoelectronic, and photonic devices due to the possibility of tuning their properties over a wide parameter range simply by adjusting the alloy composition. Interestingly, the material properties are also determined by the atomic-scale structure of the alloys on the subnanometer scale. These local atomic arrangements exhibit a striking deviation from the average crystallographic structure featuring different element-specific bond lengths, pronounced bond angle relaxation and severe atomic displacements. The latter, in particular, have a strong influence on the bandgap energy and give rise to a significant contribution to the experimentally observed bandgap bowing. This article therefore reviews experimental and theoretical studies of the atomic-scale structure of III-V and II-VI zincblende alloys and I-III-VI{sub 2} chalcopyrite alloys and explains the characteristic findings in terms of bond length and bond angle relaxation. Different approaches to describe and predict the bandgap bowing are presented and the correlation with local structural parameters is discussed in detail. The article further highlights both similarities and differences between the cubic zincblende alloys and the more complex chalcopyrite alloys and demonstrates that similar effects can also be expected for other tetrahedrally coordinated semiconductors of the adamantine structural family.

  19. Elastic analysis of thermal gradient bowing in rod-type fuel elements subjected to axial thrust (LWBR Development Program)

    Energy Technology Data Exchange (ETDEWEB)

    Newman, J.B.

    1968-01-01

    Thermal radient bowing of rod type fuel elements can be analyzed in terms of the deflections of a precurved beam. The fundamental aspects of an analysis of axially compressed multispan beams are given. Elasticity of supports in both axial and transverse directions is considered; the technique is applicable to problems in which the axial thrust depends on the transverse deflection as well as problems with prescribed axial thrust. The formulas presented constitute the theory for a computer program of broad applicability, not only in the analysis of fuel rod bowing, but also to almost any multispan beam, particularly when the effects of axial loads cannot be neglected. 17 references. (NSA 22: 22866)

  20. Offset semi-parabolic nanoantenna made of a photonic crystal parabolic mirror and a plasmonic bow-tie antenna.

    Science.gov (United States)

    Hattori, Haroldo T

    2014-10-10

    In a parabolic mirror, light coming parallel to the antenna passes through its focal point. In this work, a waveguide feeds a semi-parabolic photonic crystal mirror and the emerging beam feeds a bow-tie antenna placed at the mirror's focal point-it is shown that the antenna system can not only feed a bow-tie antenna (producing a localized moderately high electric field) but also produces a directional radiation beam. The semi-parabolic mirror is also modified to reduce reflection back to the feeding waveguide.

  1. Hydroelastic Response of Surface-Effect Ship Bow Seals: Large-Scale Experiments and Post-Buckling Analysis

    Science.gov (United States)

    Wiggins, Andrew D.

    Bow seals are critical components on advanced marine vehicles that rely on aerostatic support to reduce drag. They consist of a series of open-ended fabric cylinders ("fingers") that contact the free surface and, when inflated, form a compliant pressure barrier. Bow seals are unique in that, unlike a majority of structures in civil and mechanical engineering, bow seals operate in a buckled state. The response characteristics of these structures are of practical interest due to unacceptable wear rates on seal components and difficulties in predicting seal performance. Despite this, the hydroelastic response of the seal system, particularly basic information on seal vibration modes and the mechanisms responsible for seal wear, remains largely unknown. Similarly, estimates of the hydrodynamic loads on the seal system are inaccurate and based on heuristic scaling of data from small-scale experiments, where similitude is challenging to maintain. Thus, a large-scale test system is necessary to obtain accurate estimates of bow seal response. The work is comprised of three parts. Part one presents detailed observations of bow seal response acquired using a large-scale test platform developed as part of the present study. These high-resolution observations, the first of their kind, show bow seal response to be characterized by complex post-buckling behavior. Part two proposes an analytical framework for interpreting the wide range of behavior observed at large scale. Using this framework, key parameters driving seal conformation and stability are identified. It is found that, due to their buckled state, bow seals are highly susceptible to a mode switching instability, which may be a potential mechanism responsible for the damaging vibrations. In part three, a benchtop experiment is used to demonstrate that the scalings identified in this study hold across a wide range of bending rigidities. This work has implications for improving drag and wear characteristics in future bow

  2. Recent H-alpha Results on Pulsar B2224+65's Bow-Shock Nebula, the "Guitar"

    Science.gov (United States)

    Dolch, Timothy; Chatterjee, Shami; Clemens, Dan P.; Cordes, James M.; Cashmen, Lauren R.; Taylor, Brian W.

    2016-09-01

    We used the 4 m Discovery Channel Telescope (DCT) at Lowell observatory in 2014 to observe the Guitar Nebula, an Hα bow-shock nebula around the high-velocity radio pulsar B2224+65. Since the nebula's discovery in 1992, the structure of the bow-shock has undergone significant dynamical changes. We have observed the limb structure, targeting the “body” and “neck” of the guitar. Comparing the DCT observations to 1995 observations with the Palomar 200-inch Hale telescope, we found changes in both spatial structure and surface brightness in the tip, head, and body of the nebula.

  3. STRAWBERRY MOUNTAIN WILDERNESS, OREGON.

    Science.gov (United States)

    Thayer, T.P.; Stotelmeyer, Ronald B.

    1984-01-01

    The Strawberry Mountain Wilderness extends 18 mi along the crest of the Strawberry Range and comprises about 53 sq mi in the Malheur National Forest, Grant County, Oregon. Systematic geologic mapping, geochemical sampling and detailed sampling of prospect workings was done. A demonstrated copper resource in small quartz veins averaging at most 0. 33 percent copper with traces of silver occurs in shear zones in gabbro. Two small areas with substantiated potential for chrome occur near the northern edge of the wilderness. There is little promise for the occurrence of additional mineral or energy resources in the Strawberry Mountain Wilderness.

  4. Himalayan Mountain Range, India

    Science.gov (United States)

    1981-01-01

    Snow is present the year round in most of the high Himalaya Mountain Range (33.0N, 76.5E). In this view taken at the onset of winter, the continuous snow line can be seen for hundreds of miles along the south face of the range in the Indian states of Punjab and Kashmir. The snow line is at about 12,000 ft. altitude but the deep Cenab River gorge is easily delineated as a break along the south edge of the snow covered mountains. '

  5. Woods with physical, mechanical and acoustic properties similar to those of Caesalpinia echinata have high potential as alternative woods for bow makers

    Directory of Open Access Journals (Sweden)

    Eduardo Luiz Longui

    2014-09-01

    Full Text Available For nearly two hundred years, Caesalpinia echinata wood has been the standard for modern bows. However, the threat of extinction and the enforcement of trade bans have required bow makers to seek alternative woods. The hypothesis tested was that woods with physical, mechanical and acoustic properties similar to those of C. echinata would have high potential as alternative woods for bows. Accordingly, were investigated Handroanthus spp., Mezilaurus itauba, Hymenaea spp., Dipteryx spp., Diplotropis spp. and Astronium lecointei. Handroanthus and Diplotropis have the greatest number of similarities with C. echinata, but only Handroanthus spp. showed significant results in actual bow manufacture, suggesting the importance of such key properties as specific gravity, speed of sound propagation and modulus of elasticity. In practice, Handroanthus and Dipteryx produced bows of quality similar to that of C. echinata.

  6. Understand mountain studies from earthquake

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Sichuan earthquake on 12 May was the most devastating one to hit China over the past 60 years or so. As the affected were mostly mountainous areas, serious damages were caused by various secondary disasters ranging from mountain collapse to the formation of quake lakes. This leaves Prof. DENG Wei, director-general of the Institute of Mountain Hazards and Environment, CAS, much to think about, and he is calling for strengthening studies on mountain science.

  7. A Review of Density Holes Upstream of Earth's Bow Shock%A Review of Density Holes Upstream of Earth's Bow Shock

    Institute of Scientific and Technical Information of China (English)

    G K Parks; E Lee; N Lin; J B Cao; S Y Fu; J K Shi

    2011-01-01

    Larmor size transient structures with density depletions as large as 99% of ambient solar wind density levels occur commonly upstream of Earth's collisionless bow shock. These "density holes" have a mean duration of 17.9±10.4s but holes as short as 4 s have been observed. The average fractional density depletion (Sn/n) inside the holes is 0.68±0.14. The density of the upstream edge moving in the sunward direction can be enhanced by five or more times the solar wind density. Particle distributions show the steepened edge can behave like a shock, and measured local field geometries and Mach number support this view. Similarly shaped magnetic holes accompany the density holes indicating strong coupling between fields and particles. Current densities as large as 150 nA·m^-2 are observed at the leading compressed edge. The waves are elliptically polarized and rotating in the sense of ions (left hand) in the plasma frame. The waves appear to grow and steepen as the density holes convect with the solar wind toward the Earth. The transient nature of density holes suggests that the temporal features could represent the different stages of nonlinear evolutionary processes that produce a shock-like structure. The density holes are only observed with upstream particles, suggesting that back-streaming particles interacting with the solar wind are important. The significance of these observations is still being investigated.

  8. Application of the Bow Tie method for evaluation of safety in the procedure of logging wells; Aplicacion del metodo de Bow Tie para la evaluacion de seguridad en la practica de perfilaje de pozos

    Energy Technology Data Exchange (ETDEWEB)

    Alfonso Pallares, C; Perez Reyes, Y.; Sarabia Molina, I.I. [Centro Nacional de Seguridad Nuclear (CNSN), La Habana (Cuba)

    2013-07-01

    This work consists of an assessment of security in the practice of logging of oil wells, using the method of Bow Tie for being a simple method of evaluation of the risk, which makes it possible in a structured way to set priorities to manage risk.

  9. Xiuhua Mountain Museum

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    XIUHUA Mountain Museum,a building nestled amongthe hills,is the first private museum of the Tujiaethnicity.Its name is an amalgamation of the names ofthe couple who run it,Gong Daoxiu and her husband ChenChuhua.According to Chen,the reason that he put his wife’s

  10. Ecological assessment of a southeastern Brazil reservoir

    OpenAIRE

    Martins,Isabela; Sanches,Barbara; Kaufmann,Philip Robert; Hughes,Robert M.; Santos,Gilmar Bastos; Molozzi,Joseline; Callisto, Marcos

    2015-01-01

    Reservoirs are artificial ecosystems with multiple functions having direct and indirect benefits to humans; however, they also cause ecological changes and influence the composition and structure of aquatic biota. Our objectives were to: (1) assess the environmental condition of Nova Ponte Reservoir, Minas Gerais state, southeastern Brazil; and (2) determine how the aquatic biota respond to disturbances. A total of 40 sites in the littoral zone of the reservoir were sampled to characterize ph...

  11. Southeastern Power Administration 2007 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2007-12-28

    Dear Secretary Chu: I am proud to submit Southeastern Power Administration’s (Southeastern’s) fiscal year (FY) 2007 Annual Report for your review. The information included in this report reflects Southeastern’s programs, accomplishments, and financial activities for the 12-month period beginning October 1, 2006 and ending September 30, 2007. Southeastern marketed more than 5 billion kilowatt-hours of energy to 492 wholesale Federal power customers in an 11-state marketing area in FY 2007. Revenues from the sale of this power totaled approximately $219 million. Drought conditions continued to plague the southeast region of the United States during 2007 placing strains on our natural and financial resources. Southeastern purchased more than $40 million in replacement power to meet customer contract requirements to ensure the continued reliability of our nation’s power grid. With the financial assistance and support of our Federal power customers, continued funding for capitalized equipment replacements at various Corps of Engineers’ (Corps) hydroelectric projects provided much needed repairs and maintenance for aging facilities. Southeastern’s cyber and physical security program continued to be reviewed and updated to meet Department of Energy (DOE), Homeland Security, and North American Electric Reliability Corporation standards and requirements. Plans for the upcoming year include communication and cooperation with DOE, Federal power customers, and the Corps to maximize the benefits of our nation’s water resources. Competition for the use of water and the prolonged drought conditions will present another challenging year for our agency. The employees at Southeastern will be proactive in meeting these challenges and providing reliable hydroelectric power to the people in the southeast. Sincerely, Kenneth E. Legg Administrator

  12. Digital mountains: toward development and environment protection in mountain regions

    Science.gov (United States)

    Jiang, Xiaobo

    2007-06-01

    Former studies on mountain system are focused on the department or subject characters, i.e. different department and branches of learning carry out researches only for their individual purposes and with individual characters of the subject of interests. As a whole, their investigation is lacking of comprehensive study in combination with global environment. Ecological environment in mountain regions is vulnerable to the disturbance of human activities. Therefore, it is a key issue to coordinate economic development and environment protection in mountain regions. On the other hand, a lot of work is ongoing on mountain sciences, especially depending on the application of RS and GIS. Moreover, the development of the Digital Earth (DE) provides a clue to re-understand mountains. These are the background of the emergence of the Digital Mountains (DM). One of the purposes of the DM is integrating spatial related data and information about mountains. Moreover, the DM is a viewpoint and methodology of understanding and quantifying mountains holistically. The concept of the DM is that, the spatial and temporal data related to mountain regions are stored and managed in computers; moreover, manipulating, analyzing, modeling, simulating and sharing of the mountain information are implemented by utilizing technologies of RS, GIS, GPS, Geo-informatic Tupu, computer, virtual reality (VR), 3D simulation, massive storage, mutual operation and network communication. The DM aims at advancing mountain sciences and sustainable mountain development. The DM is used to providing information and method for coordinating the mountain regions development and environment protection. The fundamental work of the DM is the design of the scientific architecture. Furthermore, construct and develop massive databases of mountains are the important steps these days.

  13. Sattleria revisited: unexpected cryptic diversity on the Balkan Peninsula and in the south-eastern Alps (Lepidoptera: Gelechiidae).

    Science.gov (United States)

    Huemer, Peter; Timossi, Giovanni

    2014-03-21

    The taxonomy of Sattleria Povolný from the high mountain systems on the Balkan Peninsula and the adjacent parts of the Alps (south-eastern Alps, Dinaric Alps, Rila Mountains) is revised based on recently collected material and re-examined museum vouchers. Adult morphology and molecular data of the COI barcode region support the existence of six strictly allopatric species in this area, including four new species: Sattleria sophiae Timossi, sp. nov. (Parco Paneveggio-Pale di San Martino, Dolomites, Prov. Trento, Italy), Sattleria dolomitica Huemer, sp. nov. (Eastern Dolomites, Prov. South Tyrol, Italy), Sattleria dinarica Huemer, sp. nov. (Durmitor NP, Dinaric Alps, Montenegro) and Sattleria haemusi Huemer, sp. nov. (Rila Mts., Bulgaria; Šar Planina, Macedonia). 

  14. Numerical Analysis of Interaction Between Single-Pulse Laser-Induced Plasma and Bow Shock in a Supersonic Flow

    Institute of Scientific and Technical Information of China (English)

    FANG Juan; HONG Yanji; LI Qian

    2012-01-01

    The interaction of laser-induced plasma and bow shock over a blunt body is inves- tigated numerically in an M∞ =6.5 supersonic flow. A ray-tracing method is used for simulating the process of laser focusing. The gas located at the focused zone is ionized and broken down and transformed into plasma. In a supersonic flow the plasma moves downstream and begins to interact with the bow shock when it approaches the surface of the blunt body. The parameters of flowfield and blunt body surface are changed due to the interaction. By analyzing phenomena occurring in the complex unsteady flowfield during the interaction in detail, we can better under- stand the change of pressure on the blunt body surface and the mechanism of drag reduction by laser energy deposition. The results show that the bow shock is changed into an oblique shock due to the interaction of the laser-induced low-density zone with the bow shock, so the wave drag of the blunt body is reduced.

  15. Is "Bow" for an Arrow or for Hair? A Classroom Demonstration on Gender Differences in Interpreting Ambiguous Information

    Science.gov (United States)

    Fa-Kaji, Naomi; Nguyen, Linda; Hebl, Mikki; Skorinko, Jeanine

    2016-01-01

    This article details a classroom demonstration of how gender differences in cognitive schemas can result in men and women differentially interpreting the same information. Students heard a series of six homonyms (e.g., bow and nail) spoken aloud and wrote down the first word with which they free-associated each homonym. When hearing the words…

  16. 76 FR 78234 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland, Campbell County, WY...

    Science.gov (United States)

    2011-12-16

    ... Forest Service Medicine Bow-Routt National Forests and Thunder Basin National Grassland, Campbell County..., LLC to vacate and relocate portions of Campbell County Road 69, Mackey Road, onto National Forest... Sections 29-31 of T. 43 N., R. 69 W., 6th Principal Meridian, Campbell County, Wyoming. DATES:...

  17. Role of In-segregation in anomalously large band-gap bowings of (In,Al,Ga)N

    DEFF Research Database (Denmark)

    Gorczyka, I.; Suski, T.; Christensen, Niels Egede;

    2011-01-01

    Large bowings of the band gap and its pressure coefficient in In-containing nitride semiconductor alloys are observed. Photoluminescence measurements for InxGa1-xN and InxAl1-xN combined with other experimental data show large scatter of the results. A comparison with ab-initio calculations sugge...

  18. Identification of the nonlinear excitation force acting on a bowed string using the dynamical responses at remote locations

    Energy Technology Data Exchange (ETDEWEB)

    Debut, V.; Antunes, J. [ITN, ADL, P-2686 Sacavem Codex (Portugal); Delaune, X. [CEA Saclay, DEN, DM2S, SEMT, Lab Etud Dynam, F-01101 Gif Sur Yvette (France)

    2010-07-01

    For achieving realistic numerical simulations of bowed string instruments, based on physical modeling, a good understanding of the actual friction interaction phenomena is of great importance. Most work published in the field including our own has assumed that bow/string frictional forces behave according to the classical Coulomb stick-slip model, with an empirical velocity-dependent sliding friction coefficient. Indeed, the basic self-excited string motions (such as the Helmholtz regime) are well captured using such friction model. However, recent work has shown that the tribological behavior of the bow/string rosin interface is rather complex, therefore the basic velocity-dependent Coulomb model may be an over-simplistic representation of the friction force. More specifically, it was suggested that a more accurate model of the interaction force can be achieved by coupling the system dynamical equations with a thermal model which encapsulates the complex interface phenomena. In spite of the interesting work performed by Askenfelt, a direct measurement of the actual dynamical friction forces without disturbing the string motion is quite difficult. Therefore, in this work we develop a modal-based identification technique making use of inverse methods and optimization techniques, which enables the identification of the interface force, as well as the string self-excited motion, from the dynamical reactions measured at the string end supports. The method gives convincing results using simulated data originated from nonlinear computations of a bowed string. Furthermore, in cases where the force identifications are very sensitive to errors in the transfer function modal parameters, we suggest a method to improve the modal frequencies used for the identifications. Preliminary experimental results obtained using a basic bowing device, by which the string is excited with the stick of the bow, are then presented. Our identifications, from the two dynamical string reactions

  19. On the origin of hot diamagnetic cavities near the earth's bow shock

    Science.gov (United States)

    Thomsen, M. F.; Gosling, J. T.; Bame, S. J.; Quest, K. B.; Russell, C. T.

    1988-01-01

    The origin of hot diamagnetic cavities (HDCs) observed occasionally upstream from the earth's bow shock is investigated by examining the results of November 16, 1977, observation, when four of these events occurred on a single day, as well as plasma and field data from that day. The results suggest that HDCs may form as a result of an unusually strong interaction between shock-reflected ions and the incoming solar wind. It is proposed that this interaction stems from a temporary and localized reflection of a larger-than-normal fraction of the incident ions, which is stimulated by sudden changes in the upstream field orientation; the consequences of such a temporary overreflection are found to be consistent with many of the observed features of HDCs, including the strong slowing, deflection, and heating of the flow, as well as the localization, internal recoveries, and occasional formation upstream from the shock itself.

  20. Observational evidence on the origin of ions upstream of the earth's bow shock

    Science.gov (United States)

    Thomsen, M. F.; Gosling, J. T.; Schwartz, S. J.

    1983-01-01

    The kinematic formalism described by Schwartz et al. (1983) is used to quantitatively compare the zeroth order predicted energies for four different source hypotheses for ions detected upstream of the earth's bow shock with previously published observations of upstream field-aligned beams and gyrating ion events. Specular reflection of a fraction of the incident solar wind is found to be the most credible explanation of gyrating ion events observed upstream of shocks ranging from quasi-parallel to nearly perpendicular. The recent hypothesis that field-aligned beams are the result of leakage from the magnetosheath of ions which were originally specularly reflected at quasi-perpendicular portions of the shock provides good agreement with observed energies of many field-aligned beams. Only magnetic moment conserving reflection of solar wind ions is capable of accounting for two very energetic beam events.

  1. Quantitative spectroscopy on individual wire, slot, bow-tie, rectangular, and square-shaped optical antennas.

    Science.gov (United States)

    Husnik, Martin; Niegemann, Jens; Busch, Kurt; Wegener, Martin

    2013-11-15

    By using a recently introduced approach combining a focus-modulation technique with a common-path interferometer, we measure quantitatively the extinction, scattering, and absorption cross-section spectra of individual optical antennas. The experimental results on thin-wire antennas, slot antennas, bow-tie antennas, rectangular antennas, and square-shaped antennas resonating at around 1.4 μm wavelength are discussed. We find increased resonant scattering cross sections for the latter four antennas compared to the thin-wire antenna, both in absolute terms and relative to the absorption cross section. The square-shaped antenna's resonant extinction cross section approaches the limit of a coherent point dipole. However, the ratio of the resonant extinction cross section to the geometrical cross section of 38 is largest for the simple thin-wire antenna.

  2. Method for measuring violin sound radiation based on bowed glissandi and its application to sound synthesis.

    Science.gov (United States)

    Perez Carrillo, Alfonso; Bonada, Jordi; Patynen, Jukka; Valimaki, Vesa

    2011-08-01

    This work presents a method for measuring and computing violin-body directional frequency responses, which are used for violin sound synthesis. The approach is based on a frame-weighted deconvolution of excitation and response signals. The excitation, consisting of bowed glissandi, is measured with piezoelectric transducers built into the bridge. Radiation responses are recorded in an anechoic chamber with multiple microphones placed at different angles around the violin. The proposed deconvolution algorithm computes impulse responses that, when convolved with any source signal (captured with the same transducer), produce a highly realistic violin sound very similar to that of a microphone recording. The use of motion sensors allows for tracking violin movements. Combining this information with the directional responses and using a dynamic convolution algorithm, helps to improve the listening experience by incorporating the violinist motion effect in stereo.

  3. Band gap bowing and electron localization of (GaxIn1-x)N

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byounghak; Wang, Lin-Wang

    2006-05-09

    The band gap bowing and the electron localization ofGaxIn1-xN are calculated using both the local density approximation (LDA)and screened-exchange local density functional (sX-LDA) methods. Thecalculated sX-LDA band gaps are in good agreement with the experimentallyobserved values, with errors of -0.26 and 0.09 eV for bulk GaN and InN,respectively. The LDA band gap errors are 1.33 and 0.81 eV for GaN andInN, in order. In contrast to the gap itself, the band gap bowingparameter is found to be very similar in sX-LDA and LDA. We identify thelocalization of hole states in GaxIn1-xN alloys along In-N-In chains. Thepredicted localizationis stronger in sX-LDA.

  4. Multispacecraft observations of the terrestrial bow shock and magnetopause during extreme solar wind disturbances

    DEFF Research Database (Denmark)

    Tatrallyay, M.; Erdos, G.; Nemeth, Z.

    2012-01-01

    by the interplanetary magnetic field (IMF) component transverse to the solar wind flow. The observed magnetopause crossings could be predicted with a reasonable accuracy (0.1-0.2 RE) by one of the presented models at least. For geosynchronous magnetopause crossings observed by the GOES satellites, (1) the new model...... provided the best predictions when the IMF was extremely large having a large negative Bz component, and (2) the predictions of the model of Shue et al. (1998) agreed best with the observations when the solar wind dynamic pressure was extremely large. The magnetopause crossings close to the cusp observed......Three events are discussed from the declining phase of the last solar cycle when the magnetopause and/or the bow shock were observed unusually close to the Earth due to major interplanetary disturbances. The observed extreme locations of the discontinuities are compared with the predictions...

  5. On the proper Mach number and ratio of specific heats for modeling the Venus bow shock

    Science.gov (United States)

    Tatrallyay, M.; Russell, C. T.; Luhmann, J. G.; Barnes, A.; Mihalov, J. D.

    1984-01-01

    Observational data from the Pioneer Venus Orbiter are used to investigate the physical characteristics of the Venus bow shock, and to explore some general issues in the numerical simulation of collisionless shocks. It is found that since equations from gas-dynamic (GD) models of the Venus shock cannot in general replace MHD equations, it is not immediately obvious what the optimum way is to describe the desired MHD situation with a GD code. Test case analysis shows that for quasi-perpendicular shocks it is safest to use the magnetospheric Mach number as an input to the GD code. It is also shown that when comparing GD predicted temperatures with MHD predicted temperatures total energy should be compared since the magnetic energy density provides a significant fraction of the internal energy of the MHD fluid for typical solar wind parameters. Some conclusions are also offered on the properties of the terrestrial shock.

  6. Large parallel and perpendicular electric fields on electron spatial scales in the terrestrial bow shock

    CERN Document Server

    Bale, S D

    2007-01-01

    Large parallel ($\\leq$ 100 mV/m) and perpendicular ($\\leq$ 600 mV/m) electric fields were measured in the Earth's bow shock by the vector electric field experiment on the Polar satellite. These are the first reported direct measurements of parallel electric fields in a collisionless shock. These fields exist on spatial scales comparable to or less than the electron skin depth (a few kilometers) and correspond to magnetic field-aligned potentials of tens of volts and perpendicular potentials up to a kilovolt. The perpendicular fields are amongst the largest ever measured in space, with energy densities of $\\epsilon_0 E^2/ n k_b T_e$ of order 10%. The measured parallel electric field implies that the electrons can be demagnetized, which may result in stochastic (rather than coherent) electron heating.

  7. STEREO measurements of electron acceleration beyond fast Fermi at the bow shock

    CERN Document Server

    Pulupa, Marc; Opitz, Andrea; Fedorov, Andrei; Lin, Robert P; Sauvaud, Jean-Andre

    2012-01-01

    Solar wind electrons are accelerated and reflected upstream by the terrestrial bow shock into a region known as the electron foreshock. Previously observed electron spectra at low energies are consistent with a fast Fermi mechanism, based on the adiabatic conservation of the magnetic moment ({\\mu}) of the accelerated electrons. At higher energies, suprathermal power law tails are observed beyond the level predicted by fast Fermi. The SWEA and STE electron detectors on STEREO enable measurements of foreshock electrons with good energy resolution and sensitivity over the entire foreshock beam. We investigate the electron acceleration mechanism by comparing observed STEREO electron spectra with predictions based on a Liouville mapping of upstream electrons through a shock encounter. The foreshock electron beam extends up to several tens of keV, energies for which the Larmor radii of electrons is tens of km or greater. These radii are comparable to the scale sizes of the shock, and {\\mu} conservation no longer ap...

  8. Dynamics of bow-tie shaped bursting: Forced pendulum with dynamic feedback

    Science.gov (United States)

    Hongray, Thotreithem; Balakrishnan, Janaki

    2016-12-01

    A detailed study is performed on the parameter space of the mechanical system of a driven pendulum with damping and constant torque under feedback control. We report an interesting bow-tie shaped bursting oscillatory behaviour, which is exhibited for small driving frequencies, in a certain parameter regime, which has not been reported earlier in this forced system with dynamic feedback. We show that the bursting oscillations are caused because of a transition of the quiescent state to the spiking state by a saddle-focus bifurcation, and because of another saddle-focus bifurcation, which leads to cessation of spiking, bringing the system back to the quiescent state. The resting period between two successive bursts (Trest) is estimated analytically.

  9. Pseudomorphic GeSn/Ge(001) quantum wells: Examining indirect band gap bowing

    Energy Technology Data Exchange (ETDEWEB)

    Tonkikh, Alexander A. [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); Institute for Physics of Microstructures RAS, GSP-105, Nizhniy Novgorod (Russian Federation); Eisenschmidt, Christian; Schmidt, Georg [Institute of Physics, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 3 D-01620, Halle (Saale) (Germany); Talalaev, Vadim G. [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); ZIK SiLi-Nano, Martin Luther University Halle-Wittenberg, Karl-Freiherr-von-Fritsch-Str. 3 D-06120, Halle (Saale) (Germany); Zakharov, Nikolay D.; Werner, Peter [Max Planck Institute of Microstructure Physics, Weinberg 2 D-06120, Halle (Saale) (Germany); Schilling, Joerg [ZIK SiLi-Nano, Martin Luther University Halle-Wittenberg, Karl-Freiherr-von-Fritsch-Str. 3 D-06120, Halle (Saale) (Germany)

    2013-07-15

    A study of the bandgap character of compressively strained GeSn{sub 0.060-0.091}/Ge(001) quantum wells grown by molecular beam epitaxy is reported. The built-in strain in GeSn wells leads to an increased separation between L and {Gamma} conduction band minima. The prevalent indirect interband transitions in GeSn were probed by photoluminescence spectroscopy. As a result we could simulate the L-valley bowing parameter in GeSn alloys, b{sub L} = 0.80 {+-} 0.06 eV at 10 K. From this we conclude that even compressively strained GeSn/Ge(001) alloys could become direct band gap semiconductors at the Sn-fraction higher than 17.0 at. %.

  10. Determination of main rational biomechanical characteristics in shooting from a bow

    Directory of Open Access Journals (Sweden)

    Adashevskiy V.M.

    2012-03-01

    Full Text Available The aim is to build rational parameters of technical actions of sportsman in shooting from a bow. It is worked out and decided mathematical model and the task of dynamics. Influence on having a special purpose exactness of corners of flight of arrow with an account and without the account of force of resistance of air environment is certain. It is distinguished the basic technical run-time errors of sportsman exercises. It is set that for successful realization of descriptions of target exactness and minimum values of deviations from an aim on different distances of shooting, sportsman must provide: maintenance of scene and rational pose, implementation of rational technical actions. It is shown directions of choice of necessary biomechanics descriptions that a sportsman can realize for providing target exactness and minimum values of deviations from aim on different distances of shooting.

  11. Treatment of pseudo Class III malocclusion by modified Hawleys appliance with inverted labial bow

    Directory of Open Access Journals (Sweden)

    K S Negi

    2011-01-01

    Full Text Available Pseudo Class III malocclusion is characterized by an anterior crossbite with functional forward mandibular displacement. Various appliances have been devised for early treatment of a pseudo Class III. The aim of this article is to highlight the method of construction and use a simple removable appliance termed as "Modified Hawleys appliance with inverted labial bow" to treat psuedo class III malocclusion in the mixed dentition period. It also emphasizes the importance of differentiating between true Class III and pseudo Class III. This appliance in this type of malocclusion enabled the correction of a dental malocclusion in a few months and therapeutic stability of a mesially positioned mandible encouraging favorable skeletal growth.

  12. Non-E x B ordered ion beams upstream of the earth's bow shock

    Science.gov (United States)

    Gurgiolo, C.; Parks, G. K.; Mauk, B. H.; Anderson, K. A.; Lin, R. P.; Reme, H.; Lin, C. S.

    1981-01-01

    The unexpected appearance of spin modulations in the fixed voltage electrostatic analyzer detectors on ISEE 1 and 2 has made it possible to study the plasma properties of the upstream ions in high time resolution. Using an isotropic flowing Maxwellian distribution to model the count rate modulations, estimates have been obtained of the local plasma temperature and three-dimensional flow velocity of the observed upstream ion population. It is found that in almost all of the observations of upstream particles there exist beam-like ions with temperatures in the range 5-80 eV. Their flow velocities cannot be ordered by E x B. This last point separates these observations from the previously reported reflected and diffuse populations of upstream ions. Mechanisms that can gyrophase bunch the ions reflected at the bow shock are discussed as a method of explaining the data.

  13. From Bows to Sound-Chests: Tracing the Ancestry of the Violin

    Directory of Open Access Journals (Sweden)

    Janelle R. Finley

    2016-04-01

    Full Text Available The ancestry of the violin is a subject that has been studied, researched, debated, and written about in great detail. However, despite all of the research and study, the ancestry of the violin is still not certain. This paper presents two schools of thought that propose different theories as to how the ancestry of the violin should be determined and what instruments should be included in the ancestry of the violin. The first school of thought proposes that the violin’s ancestry should be traced through the bow. The second theory proposes that the violin’s ancestry should be traced through the sound-chest of the violin. This paper also presents the different arguments for and against each theory, the importance of this topic, and the paper’s position on this topic. Research for this paper was accomplished through the use of scholarly books on the subject of the history of the violin.

  14. Lateralization of horizontal semicircular canal canalolithiasis and cupulopathy using bow and lean test and head-roll test.

    Science.gov (United States)

    Kim, Chang-Hee; Kim, Yong Gyu; Shin, Jung Eun; Yang, Young Soo; Im, Donghyuk

    2016-10-01

    Accurate lateralization is important to improve treatment outcomes in horizontal semicircular canal (HSCC) benign paroxysmal positional vertigo (BPPV). To determine the involved side in HSCC-BPPV, the intensity of nystagmus has been compared in a head-roll test (HRT) and the direction of nystagmus was evaluated in a bow and lean test (BLT). The aim of this study is to compare the results of a BLT with those of a HRT for lateralization of HSCC-canalolithiasis and cupulopathy (heavy cupula and light cupula), and evaluate treatment outcomes in patients with HSCC-canalolithiasis. We conducted retrospective case reviews in 66 patients with HSCC-canalolithiasis and 63 patients with HSCC-cupulopathy. The affected side was identified as the direction of bowing nystagmus on BLT in 55 % (36 of 66) of patients with canalolithiasis, which was concordant with the HRT result in 67 % (24 of 36) of cases (concordant group). Lateralization was determined by comparison of nystagmus intensity during HRT in 30 patients who did not show bowing or leaning nystagmus. The remission rate after the first treatment was 71 % (17 of 24) in the concordant group and 45 % (5 of 11) in the discordant group. Both bowing and leaning nystagmus were observed in all patients with cupulopathy, and the side of the null plane was identified as the affected side. In conclusion, bowing and/or leaning nystagmus were observed in only 55 % of patients with HSCC-canalolithiasis, and the first treatment based on the result of BLT alone was effective in only 45 % of the patients in whom the BLT and HRT were discordant, which may suggest that the usefulness of BLT in lateralizing the HSCC-canalolithiasis may be limited.

  15. Effect of direct and indirect face-bow transfer on the horizontal condylar guidance values: A pilot study

    Directory of Open Access Journals (Sweden)

    Aditi Mishra

    2014-01-01

    Full Text Available Aims and Objectives: This study aimed to evaluate the effect of direct and indirect face-bow transfer on the horizontal condylar guidance (HCG values obtained on the semi-adjustable articulator. Materials and Methods: A total of 15 subjects of age 20-30 years, of either sex were selected. Two sets of maxillary and mandibular casts were obtained. A single arbitrary face-bow record was used for mounting the maxillary casts by direct and indirect transfer for each subject. The mandibular casts were mounted using maximum intercuspation record. Protrusive records were made in Alu wax and used to program the directly and indirectly transferred casts. HCG values obtained from cephalometric records were taken as control. The data was subjected to ANOVA and Bonferroni post hoc test. Results: Mean values of HCG obtained in direct face-bow transfer were 24.93°, indirect transfer −27.66°, and cephalometric analysis −32.73°. One-way ANOVA test indicated that there was a significant difference between all the groups (P < 0.05. Tukey′s test with Bonferroni′s correction (P < 0.01 was significant for direct and indirect transfer (P = 0.008, and direct transfer and cephalometric readings (P = 0.0046. A nonsignificant difference was found between indirect transfer and cephalometric readings (P = 0.047. Conclusion : There is a statistically significant difference in HCG values obtained from direct and indirect face-bow transfer records. Lateral cephalograms gave higher mean HCG values than those obtained from protrusive records. Mean HCG values obtained from indirect face-bow transfers are significantly more than those obtained from direct transfers and are also closer to the values obtained from the lateral cephalograms.

  16. Tectonic Summaries for Web-served Earthquake Responses, Southeastern North America

    Science.gov (United States)

    Wheeler, Russell L.

    2003-01-01

    This report documents the rationale and strategy used to write short summaries of the seismicity and tectonic settings of domains in southeastern North America. The summaries are used in automated responses to notable earthquakes that occur anywhere east of the Rocky Mountains in the United States or Canada. Specifically, the report describes the geologic and tectonic information, data sources, criteria, and reasoning used to determine the content and format of the summaries, for the benefit of geologists or seismologists who may someday need to revise the summaries or write others. These tectonic summaries are designed to be automatically posted on the World Wide Web as soon as an earthquake?s epicenter is determined. The summaries are part of a larger collection of summaries that is planned to cover the world.

  17. On nonstationarity and rippling of the quasiperpendicular zone of the Earth bow shock: Cluster observations

    Directory of Open Access Journals (Sweden)

    V. V. Lobzin

    2008-09-01

    Full Text Available A new method for remote sensing of the quasiperpendicular part of the bow shock surface is presented. The method is based on analysis of high frequency electric field fluctuations corresponding to Langmuir, upshifted, and downshifted oscillations in the electron foreshock. Langmuir waves usually have maximum intensity at the upstream boundary of this region. All these waves are generated by energetic electrons accelerated by quasiperpendicular zone of the shock front. Nonstationary behavior of the shock, in particular due to rippling, should result in modulation of energetic electron fluxes, thereby giving rise to variations of Langmuir waves intensity. For upshifted and downshifted oscillations, the variations of both intensity and central frequency can be observed. For the present study, WHISPER measurements of electric field spectra obtained aboard Cluster spacecraft are used to choose 48 crossings of the electron foreshock boundary with dominating Langmuir waves and to perform for the first time a statistical analysis of nonstationary behavior of quasiperpendicular zone of the Earth's bow shock. Analysis of hidden periodicities in plasma wave energy reveals shock front nonstationarity in the frequency range 0.33 fBiBi, where fBi is the proton gyrofrequency upstream of the shock, and shows that the probability to observe such a nonstationarity increases with Mach number. The profiles observed aboard different spacecraft and the dominating frequencies of the periodicities are usually different. Hence nonstationarity and/or rippling seem to be rather irregular both in space and time rather than resembling a quasiregular wave propagating on the shock surface.

  18. ION ACCELERATION AT THE QUASI-PARALLEL BOW SHOCK: DECODING THE SIGNATURE OF INJECTION

    Energy Technology Data Exchange (ETDEWEB)

    Sundberg, Torbjörn; Haynes, Christopher T.; Burgess, D. [School of Physics and Astronomy, Queen Mary University of London, London, E1 4NS (United Kingdom); Mazelle, Christian X. [IRAP, Université Paul Sabatier Toulouse III-CNRS, 31028 Toulouse Cedex 4 (France)

    2016-03-20

    Collisionless shocks are efficient particle accelerators. At Earth, ions with energies exceeding 100 keV are seen upstream of the bow shock when the magnetic geometry is quasi-parallel, and large-scale supernova remnant shocks can accelerate ions into cosmic-ray energies. This energization is attributed to diffusive shock acceleration; however, for this process to become active, the ions must first be sufficiently energized. How and where this initial acceleration takes place has been one of the key unresolved issues in shock acceleration theory. Using Cluster spacecraft observations, we study the signatures of ion reflection events in the turbulent transition layer upstream of the terrestrial bow shock, and with the support of a hybrid simulation of the shock, we show that these reflection signatures are characteristic of the first step in the ion injection process. These reflection events develop in particular in the region where the trailing edge of large-amplitude upstream waves intercept the local shock ramp and the upstream magnetic field changes from quasi-perpendicular to quasi-parallel. The dispersed ion velocity signature observed can be attributed to a rapid succession of ion reflections at this wave boundary. After the ions’ initial interaction with the shock, they flow upstream along the quasi-parallel magnetic field. Each subsequent wavefront in the upstream region will sweep the ions back toward the shock, where they gain energy with each transition between the upstream and the shock wave frames. Within three to five gyroperiods, some ions have gained enough parallel velocity to escape upstream, thus completing the injection process.

  19. Anatomy of the internal bow shocks in the IRAS 04166+2706 protostellar jet

    Science.gov (United States)

    Tafalla, M.; Su, Y.-N.; Shang, H.; Johnstone, D.; Zhang, Q.; Santiago-García, J.; Lee, C.-F.; Hirano, N.; Wang, L.-Y.

    2017-01-01

    Context. Highly collimated jets and wide-angle outflows are two related components of the mass-ejection activity associated with stellar birth. Despite decades of research, the relation between these two components remains poorly understood. Aims: We study the relation between the jet and the outflow in the IRAS 04166+2706 protostar. This Taurus protostar drives a molecular jet that contains multiple emission peaks symmetrically located from the central source. The protostar also drives a wide-angle outflow consisting of two conical shells. Methods: We have used the Atacama Large Millimeter/submillimeter Array (ALMA) interferometer to observe two fields along the IRAS 04166+2706 jet. The fields were centered on a pair of emission peaks that correspond to the same ejection event. The observations were carried out in CO(2-1), SiO(5-4), and SO(JN = 65-54). Results: Both ALMA fields present spatial distributions that are approximately elliptical and have their minor axes aligned with the jet direction. As the velocity increases, the emission in each field moves gradually across the elliptical region. This systematic pattern indicates that the emitting gas in each field lies in a disk-like structure that is perpendicular to the jet axis and whose gas is expanding away from the jet. A small degree of curvature in the first-moment maps indicates that the disks are slightly curved in the manner expected for bow shocks moving away from the IRAS source. A simple geometrical model confirms that this scenario fits the main emission features. Conclusions: The emission peaks in the IRAS 04166+2706 jet likely represent internal bow shocks where material is being ejected laterally away from the jet axis. While the linear momentum of the ejected gas is dominated by the component in the jet direction, the sideways component is not negligible, and can potentially affect the distribution of gas in the surrounding outflow and core.

  20. Two new species of the sharpshooter genus Oragua Melichar, 1926 from Southeastern Brazil (Hemiptera: Cicadellidae: Cicadellini).

    Science.gov (United States)

    Mejdalani, Gabriel; Silva, Cristiane M F Da; Takiya, Daniela M

    2016-01-01

    Two very similar new species of Oragua Melichar, 1926, O. linnavuorii sp. nov. and O. flavolineata sp. nov., are described and illustrated from the Atlantic Forest of Southeastern Brazil (Mantiqueira mountain range). The new species share the presence of a large dentiform process located posteroventrally on the male pygofer, a unique feature within the genus. They can be distinguished from each other by the paraphyses with a pair of elongate, slender asymmetrical rami in O. linnavuorii and with two pairs of short, spiniform apical processes in O. flavolineata. The male of O. linnavuorii is macropterous but the female is submacropterous and thus smaller than the former when specimens are measured from the apex of the crown to the tips of the forewings at rest. The female of O. flavolineata is not known. Male holotypes are deposited in DZRJ. A key to males of the five Oragua species recorded from Southeastern Brazil is provided [O. maculifera Young, 1977, O. discoidula (Osborn, 1926), O. triplehorni Young, 1977, O. linnavuorii, and O. flavolineata]. The superficially similar genera Oragua and Aguana Melichar, 1926 are briefly compared.

  1. Three centuries of winter temperature change on the southeastern Tibetan Plateau and its relationship with the Atlantic Multidecadal Oscillation

    Science.gov (United States)

    Shi, Shiyuan; Li, Jinbao; Shi, Jiangfeng; Zhao, Yesi; Huang, Gang

    2016-10-01

    Long-term, high-resolution proxy records containing cold season temperature signals are scarce on the southeastern Tibetan Plateau (TP), limiting our understanding of regional climate and the potential driving forces. In this study, we present a nearly three centuries long reconstruction of winter (December-February) mean temperature for the central Hengduan Mountains, southeastern TP. The reconstruction is derived from a composite tree-ring width chronology of Pinus yunnanensis Franch from two high elevation sites (>3000 m above sea level). Our reconstruction passes all standard calibration-verification schemes and explains nearly 73 % of the variance of the original instrumental data. However, we were constrained to calibrate our full period (1718-2013) reconstruction of December-February mean temperature on the calibration period from 1959 to 1992 only, due to a decrease in temperature sensitivity of tree-ring index exhibited after 1992. Spatial correlation analysis shows that our reconstruction represents large-scale temperature variations in southwest China and the eastern TP. Our reconstructed December-February mean temperature shows a close association with the Atlantic Multidecadal Oscillation (AMO) over the past three centuries, with warm (cold) periods coinciding with the positive (negative) phases of the AMO. This persistent relationship suggests that the AMO may have been a key driver of multidecadal winter temperature variations on the southeastern TP.

  2. Velocity structure and seismicity of southeastern Tennessee

    Science.gov (United States)

    Kaufmann, Ronald Douglas; Long, Leland Timothy

    1996-04-01

    The seismic zone in southeastern Tennessee is at the confluence of major crustal features, which have been interpreted largely from potential data, and their relation to seismicity could help us understand why major earthquakes sometimes occur in the eastern United States. In this paper we solve for the previously unknown velocity structure of the upper crust by an inversion of travel time residuals from relocated earthquakes. The gravity anomalies are included by using a linear relation between average anomalous density and average anomalous velocity. The velocity model demonstrates that the seismicity is concentrated in areas of average to below average velocity and does not appear to be associated with one of the previously identified major crustal features. The high-velocity zones mark areas that are generally lacking in seismicity. The association of earthquake hypocenters with regions of low-velocity crustal rocks is consistent with other intraplate seismic zones, and this association supports the conjecture that intraplate earthquakes occur in crust that may have been weakened. The velocity anomalies at midcrustal depths do not support the New York-Alabama (NY-AL) lineament as a linear feature extending through southeastern Tennessee and parallel to contours in gravity anomalies as originally proposed. A continuation of the (NY-AL) lineament to the southwest requires either a 15 degree southwestward change in direction or a displacement to be consistent with the velocity anomalies. The seismically active areas in southeastern Tennessee do not appear to be constrained by the major crustal features, but instead, the seismicity is characterized by the distribution of hypocenters and their association with low-velocity regions at midcrustal depths.

  3. Maximum extent of Late Pleistocene glaciers and last deglaciation of La Cerdanya mountains, Southeastern Pyrenees

    Science.gov (United States)

    Palacios, David; Gómez-Ortiz, Antonio; Andrés, Nuria; Vázquez-Selem, Lorenzo; Salvador-Franch, Ferran; Oliva, Marc

    2015-02-01

    This paper examines glacial evolution in the La Pera and Malniu cirques, and Arànser, La Llosa and Duran valleys, in the Cerdanya massifs on the south-facing slopes of the eastern Pyrenees. A geomorphologic analysis and dating of moraine boulders, glacially polished bedrock and rock glacier blocks were carried out by means of cosmogenic 36Cl surface exposure dating. The maximum ice advance was contemporary with the Last Glacial Maximum at 23 ka ago, and it was of greater or only slightly lesser magnitude than for previous Quaternary advances. The termini of glaciers remained close to maximum positions, with minor advances and retreats until 18-17 ka when the glacial tongues disappeared from the valleys. Depending on the previous topography, these glaciers left behind a single polygenic moraine, in the case of confined valleys, or multiple moraines next to each other in the case of flat, more open areas. A final glacial advance is detected during the Oldest Dryas close to the cirque headwalls, and the glaciers finally disappeared during the Bølling interstadial. The glaciers were then replaced by rock glaciers, whose front immediately became inactive, although their activity continued near their source area until the early Holocene.

  4. VASCULAR PLANTS OF SOUTHEASTERN OKLAHOMA FROM THE SANS BOIS TO THE KIAMICHI MOUNTAINS

    Directory of Open Access Journals (Sweden)

    Francis Hobart Means, Jr.

    2009-12-01

    Full Text Available The author grew up in the prairie region of Kay County where he learned to appreciate proper management of the soil and the native grass flora. After graduation from college, he moved to Eastern Oklahoma State College where he took a position as Instructor in Botany and Agronomy. In the course of conducting botany field trips and working with local residents on their plant problems, the author became increasingly interested in the flora of that area and of the State of Oklahoma. This led to an extensive study of the northern portion of the Oauchita Highlands with collections currently numbering approximately 4,200. The specimens have been processed according to standard herbarium procedures. The first set has been placed in the Herbarium of Oklahoma State University with the second set going to Eastern Oklahoma State College at Wilburton.

  5. Upward flow of magmatic fluids from the Old Woman granodiorite, Old Woman Mountains southeastern California

    Science.gov (United States)

    Morrison, Jean; Hoisch, Thomas D.

    1994-05-01

    Isotopic compositions, mineral equilibrium, and field relations at the contact between the midcrustal Cretaceous Old Woman granodiorite and Paleozoic carbonates indicate that water-rich, silica-saturated magmatic fluids were transported upward, away from the pluton, across an impermeable 30- to 40-m thick marble which caps the granodiorite, to higher structural levels along a complex network of hydrologically induced fractures. Within the fractures, fluids reacted to form symmetrical radiating splays of wollastonite with minor amounts of diopside, vesuvianite, and quartz. In many cases, pegmatites are found in the center of these calc-silicate skarns. Cross-cutting pegmatites and wollastonite veins in the aureole indicate that during late stages of crystallization of the granodiorite there were multiple episodes of fluid expulsion. Above the marble layer at higher structural levels, magmatic fluids flowed both laterally and vertically, interacting with lithologies in a more pervasive manner. Values of delta O-18 for calcite in the vein skarns average 11.8% and pegmatite whole rock silicate delta O-18 values average 9.4%. Thus oxygen isotopic compositions are consistent with a magmatic origin for the skarn-forming fluids. Away from the vein skarns, values of delta O-18 for the capping marble range from 18.7 to 22.1% (avg. = 21%) and values of delta C-13 range from -3.8 to -3.0% (avg. = -3.4%). The high delta O-18 values provide evidence that the marble largely retained its premetamorphic isotopic composition, indicating that fluids from the granodiorite did not flow pervasively across the unit. Lithologies at higher structural levels show evidence of more pervasive interaction with magmatic fluids: forsterite-bearing calc-silicates have delta O-18 values down to 11.8% and coarse-grained vesuvianite- and wollastonite-bearing skarns have delta O-18 values of approximately 13%.

  6. Patient-centred mountain medicine.

    Science.gov (United States)

    Szawarski, Piotr; Hillebrandt, David

    2016-08-01

    Venturing into the mountains, doctors have accompanied expeditions to provide routine care to the teams, undertake research and occasionally take on a rescue role. The role of doctors practicing mountain medicine is evolving. Public health issues involving concepts of health and safety have become necessary with the coming of commercial and youth expeditions. Increasingly individuals with a disability or a medical diagnosis choose to ascend to high altitudes. Doctors become involved in assessment of risk and providing advice for such individuals. The field of mountain medicine is perhaps unique in that acceptance of risk is part of the ethos of climbing and adventure. The pursuit of mountaineering goals may represent the ultimate conquest of a disability. Knowledge of mountain environment is essential in facilitating mountain ascents for those who choose to undertake them, in spite of a disability or medical condition.

  7. HENDUAN MOUNTAINS A Dazzling World

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Indian Continent drifted northward and eventually collideawith the Euro-Asian Continent,pushing up the piece of land weknow today as the Himalayas and Henduan Mountains.Located where Qinghai,Tibet,Yunnan and Sichuan all meet.Asia,including the Nujiang,Jinshajiang and Lancanjiang.In the mountains,rivers Wave a drop of about 2,500 meters.Late last year,we drove into the mountainous area,covering adistance of some 1,000 km.

  8. A Breath of Mountain Air

    Institute of Scientific and Technical Information of China (English)

    YU LINTAO

    2011-01-01

    Mountains are everywhere,and rivers flow in almost every valley.This is the Qinling Mountains,a major eastto-west range in southern Shaanxi Province,bordering Hubei and Henan provinces.Because of its huge forest coverage,the Qinling Mountains are also known as one of the lungs of China.Expectations for travelling are changing in China as the lifestyle of city dwellers has become fast-paced and demanding.That provides the Qirding Mountain area a great opportunity to develop leisure tourism.

  9. Bowing and expansion of natural stone panels: marble and limestone testing and assessment

    Directory of Open Access Journals (Sweden)

    Grelk, Bent

    2008-06-01

    Full Text Available Natural stone has been used as a building material for centuries. In the past, load bearing members were made of entirely of stone, but in the last 50 years new processing techniques have made the production and use of thin facade cladding a profitable venture. Unfortunately however, marble facades on buildings in Europe and elsewhere have undergone severe deterioration. The EC-financed TEAM project (2000-2005 studied the bowing observed on marble facades in both cold and warm climates. TEAM’s main objectives were to understand and explain the expansion, bowing, and strength loss mechanisms governing the decay of marble- and limestone-clad facades, and to draft new European standards to prevent the use of marble and limestone poorly suited to outdoor cladding. A survey of some 200 buildings afforded a clear picture of the geographical, geological and climatic scope of the problem. Detailed case studies of six buildings resulted in a facade assessment methodology that included a monitoring system and risk assessment. Both laboratory and field research was conducted on almost 100 different types of stone from different countries and in place in different climates. The outcome was the determination of the decay mechanisms and critical factors. Two test methods and respective precision statements, one for bowing and the other for irreversible thermal expansion in high humidity conditions, were prepared for submission to CEN TC 246.La piedra natural se ha empleado como material de construcción durante siglos. En el pasado, se solía utilizar en elementos de carga, pero en los últimos 50 años las nuevas técnicas de procesamiento han permitido que sea comercialmente rentable producir y utilizar revestimientos para fachadas de espesor reducido. Desafortunadamente, numerosas fachadas de mármol de edificios tanto en Europa como fuera de ella han sufrido graves problemas derivados del deterioro de la piedra. El proyecto TEAM (2000

  10. Preliminary results of paleoseismic investigations of Quaternary faults on eastern Yucca Mountain, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Menges, C.M.; Oswald, J.A.; Coe, J.A. [and others

    1995-12-31

    Site characterization of the potential nuclear waste repository at Yucca Mountain, Nevada, requires detailed knowledge of the displacement histories of nearby Quaternary faults. Ongoing paleoseismic studies provide data on the amount and rates of Quaternary activity on the Paintbrush Canyon, Bow Ridge, and Stagecoach Road faults along the eastern margin of the mountain over varying time spans of 0-700 ka to perhaps 0-30 ka, depending on the site. Preliminary stratigraphic interpretations of deposits and deformation at many logged trenches and natural exposures indicate that each of these faults have experienced from 3 to 8 surface-rupturing earthquakes associated with variable dip-slip displacements per event ranging from 5 to 115 cm, and commonly in the range of 20 to 85 cm. Cumulative dip-slip offsets of units with broadly assigned ages of 100-200 ka are typically less than 200 cm, although accounting for the effects of possible left normal-oblique slip could increase these displacements by factors of 1.1 to 1.7. Current age constraints indicate recurrence intervals of 10{sup 4} to 10{sup 5} years (commonly between 30 and 80 k.y.) and slip rates of 0.001 to 0.08 mm/yr (typically 0.01-0.02 mm/yr). Based on available timing data, the ages of the most recent ruptures varies among the faults; they appear younger on the Stagecoach Road Fault ({approximately}5-20 ka) relative to the southern Paintbrush Canyon and Bow Ridge faults ({approximately}30-100 ka).

  11. "Christ is the Mountain"

    Directory of Open Access Journals (Sweden)

    Carl Hallencreutz

    1979-01-01

    Full Text Available In this paper the author focuses on the religious function of symbols in the encounter and interaction of Christianity and other religions. Some observations on the religious function of the symbol of the Holy Mountain in different African contexts are presented. These contexts are a traditional Kikuyu religion, b a Christian hymn from Northern Tanzania, and c the New Year's Fiest of the independent Nazaretha Church among Zulu in South Africa. The examples of how the symbol of the holy mountain is used in different religious contexts in Africa are, of course, too limited to provide a basis for far-reaching generalizations on how symbols function religiously in the encounter of Christianity and other religions. However, this kind of analysis can be applied also when studying other encounters of religions inside and outside Africa. The symbol functions both as a carrier of a new religious message and as an indigenous means to appropriate this message locally and give it adequate form in different milieus. The symbols, which most likely have the religious functions are those which are of a general nature; light, way, living water, and which some are tempted to speak of as archetypes. Yet the comparison between the Chagga-hymn to the holy mountain and Shembe's interpretation of the blessing of the New Year's Fiest on Inhlangakozi indicates, that in the encounter of Christianity and other religions it is not only the symbols as such which produce the local appropriation of the new religious message and give it adequate localized form. Not even in the encounter of Christianity and other religions the symbols function religiously without human beings as actors in the historical process.

  12. Human impacts to mountain streams

    Science.gov (United States)

    Wohl, Ellen

    2006-09-01

    Mountain streams are here defined as channel networks within mountainous regions of the world. This definition encompasses tremendous diversity of physical and biological conditions, as well as history of land use. Human effects on mountain streams may result from activities undertaken within the stream channel that directly alter channel geometry, the dynamics of water and sediment movement, contaminants in the stream, or aquatic and riparian communities. Examples include channelization, construction of grade-control structures or check dams, removal of beavers, and placer mining. Human effects can also result from activities within the watershed that indirectly affect streams by altering the movement of water, sediment, and contaminants into the channel. Deforestation, cropping, grazing, land drainage, and urbanization are among the land uses that indirectly alter stream processes. An overview of the relative intensity of human impacts to mountain streams is provided by a table summarizing human effects on each of the major mountainous regions with respect to five categories: flow regulation, biotic integrity, water pollution, channel alteration, and land use. This table indicates that very few mountains have streams not at least moderately affected by land use. The least affected mountainous regions are those at very high or very low latitudes, although our scientific ignorance of conditions in low-latitude mountains in particular means that streams in these mountains might be more altered than is widely recognized. Four case studies from northern Sweden (arctic region), Colorado Front Range (semiarid temperate region), Swiss Alps (humid temperate region), and Papua New Guinea (humid tropics) are also used to explore in detail the history and effects on rivers of human activities in mountainous regions. The overview and case studies indicate that mountain streams must be managed with particular attention to upstream/downstream connections, hillslope

  13. Dispersion of low frequency plasma waves upstream of the quasi-perpendicular terrestrial bow shock

    Directory of Open Access Journals (Sweden)

    A. P. Dimmock

    2013-08-01

    Full Text Available Low frequency waves in the foot of a supercritical quasi-perpendicular shock front have been observed since the very early in situ observations of the terrestrial bow shock (Guha et al., 1972. The great attention that has been devoted to these type of waves since the first observations is explained by the key role attributed to them in the processes of energy redistribution in the shock front by various theoretical models. In some models, these waves play the role of the intermediator between the ions and electrons. It is assumed that they are generated by plasma instability that exist due to the counter-streaming flows of incident and reflected ions. In the second type of models, these waves result from the evolution of the shock front itself in the quasi-periodic process of steepening and overturning of the magnetic ramp. However, the range of the observed frequencies in the spacecraft frame are not enough to distinguish the origin of the observed waves. It also requires the determination of the wave vectors and the plasma frame frequencies. Multipoint measurements within the wave coherence length are needed for an ambiguous determination of the wave vectors. In the main multi-point missions such as ISEE, AMPTE, Cluster and THEMIS, the spacecraft separation is too large for such a wave vector determination and therefore only very few case studies are published (mainly for AMPTE UKS AMPTE IRM pair. Here we present the observations of upstream low frequency waves by the Cluster spacecraft which took place on 19 February 2002. The spacecraft separation during the crossing of the bow shock was small enough to determine the wave vectors and allowed the identification of the plasma wave dispersion relation for the observed waves. Presented results are compared with whistler wave dispersion and it is shown that contrary to previous studies based on the AMPTE data, the phase velocity in the shock frame is directed downstream. The consequences of this

  14. Quantified Energy Dissipation Rates in the Terrestrial Bow Shock. 2; Waves and Dissipation

    Science.gov (United States)

    Wilson, L. B., III; Sibeck, D. G.; Breneman, A. W.; Le Contel, O.; Cully, C.; Turner, D. L.; Angelopoulos, V.; Malaspina, D. M.

    2014-01-01

    We present the first quantified measure of the energy dissipation rates, due to wave-particle interactions, in the transition region of the Earth's collision-less bow shock using data from the Time History of Events and Macro-Scale Interactions during Sub-Storms spacecraft. Our results show that wave-particle interactions can regulate the global structure and dominate the energy dissipation of collision-less shocks. In every bow shock crossing examined, we observed both low-frequency (less than 10 hertz) and high-frequency (approximately or greater than10 hertz) electromagnetic waves throughout the entire transition region and into the magnetosheath. The low-frequency waves were consistent with magnetosonic-whistler waves. The high-frequency waves were combinations of ion-acoustic waves, electron cyclotron drift instability driven waves, electrostatic solitary waves, and whistler mode waves. The high-frequency waves had the following: (1) peak amplitudes exceeding delta B approximately equal to 10 nanoteslas and delta E approximately equal to 300 millivolts per meter, though more typical values were delta B approximately equal to 0.1-1.0 nanoteslas and delta E approximately equal to 10-50 millivolts per meter (2) Poynting fluxes in excess of 2000 microWm(sup -2) (micro-waves per square meter) (typical values were approximately 1-10 microWm(sup -2) (micro-waves per square meter); (3) resistivities greater than 9000 omega meters; and (4) associated energy dissipation rates greater than 10 microWm(sup -3) (micro-waves per cubic meter). The dissipation rates due to wave-particle interactions exceeded rates necessary to explain the increase in entropy across the shock ramps for approximately 90 percent of the wave burst durations. For approximately 22 percent of these times, the wave-particle interactions needed to only be less than or equal to 0.1 percent efficient to balance the nonlinear wave steepening that produced the shock waves. These results show that wave

  15. Study on the effect of the CANFLEX-NU fuel element bowing on the critical heat flux

    Energy Technology Data Exchange (ETDEWEB)

    Suk, Ho Chun; Cho, Moon Sung; Jeon, Ji Su

    2001-01-01

    The effect of the CANFLEX-NU fuel element bowing on the critical heat flux is reviewed and analyzed, which is requested by KINS as the Government design licensing condition for the use of the fuel bundles in CANDU power reactors. The effect of the gap between two adjacent fuel elements on the critical heat flux and onset-of-dryout power is studied. The reduction of the width of a single inter-rod gap from its nominal size to the minimum manufacture allowance of 1 mm has a negligible effects on the thermal-hydraulic performance of the bundle for the given set of boundary conditions applied to the CANFLEX-43 element bundle in an uncrept channel. As expected, the in-reactor irradiation test results show that there are no evidence of the element bow problems on the bundle performance.

  16. ROLE OF FCA WELDING PROCESS PARAMETERS ON BEAD PROFILE, ANGULAR AND BOWING DISTORTION OF FERRITIC STAINLESS STEEL SHEETS

    Directory of Open Access Journals (Sweden)

    VENKATESAN M. V.

    2014-02-01

    Full Text Available This paper discusses the influence of flux cored arc welding (FCAW process parameters such as welding current, travel speed, voltage and CO2 shielding gas flow rate on bead profile, bowing distortion and angular distortion of 409 M ferritic stainless steel sheets of 2 mm thickness. The bowing and angular distortions of the welded plates were measured using a simple device called profile tracer and Vernier bevel protractor respectively. The study revealed that the FCAW process parameters have significant effect on bead profile, and distortion. The relationship between bead profile and distortions were analyzed. Most favorable process parameters that give uniform bead profile and minimum distortion for the weld are recommended for fabrication.

  17. Attenuation distance of low frequency waves upstream of the pre-dawn bow shock: GEOTAIL and ISEE 3 comparison

    Science.gov (United States)

    Sugiyama, T.; Terasawa, T.; Kawano, H.; Yamamoto, T.; Kokubun, S.; Frank, L. A.; Ackerson, K.; Tsurutani, B. T.

    1995-01-01

    We have made a statistical study of the spatial distribution of low frequency waves (approx. 0.01-0.1 Hz) in the region upstream of the pre-dawn to dawn side bow shock (-50 Re less than X less than 15 Re) using both GEOTAIL and international sun earth explorer 3 (ISEE-3) magnetometer data. We have found that the wave amplitude dependence on D and X(sub s), where D is the distance from the bow shock and X(sub s) the x-coordinate position of shock foot point of the IMF, can be described by a functional form of A exp (X(sub s)/L(sub X)-D/L(sub D), with the characteristic attenuation distances, L(sub X) = 62 +/- 12 Re and L(sub D) = 59 +/- 38 Re.

  18. Attenuation distance of low frequency waves upstream of the pre-dawn bow shock: GEOTAIL and ISEE comparison

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, T.; Terasawa, T.; Kawano, H. [Univ. of Tokoyo (Japan)] [and others

    1995-01-15

    The authors have made a statistical study of the spatial distribution of low frequency waves ({approximately}0.01-0.1 Hz) in the region upstream of the pre-dawn to dawn side bow shock ({minus}50 Rebow shock and X{sub s} the x-coordinate position of shock foot point of the IMF, can be described by a functional form of A exp(X{sub s}/L{sub X}-D/L{sub D}), with the characteristic attenuation distances, L{sub X}=62{plus_minus}12 Re and L{sub D} = 59 {plus_minus} 38 Re. 13 refs., 5 figs., 1 tab.

  19. X-ray Observations of Bow Shocks around Runaway O Stars. The case of $\\zeta$ Oph and BD+433654

    CERN Document Server

    Toalá, J A; González-Gaán, A; Guerrero, M A; Ignace, R; Pohl, M

    2016-01-01

    Non-thermal radiation has been predicted within bow shocks around runaway stars by recent theoretical works. We present X-ray observations towards the runaway stars $\\zeta$ Oph (Chandra and Suzaku) and BD+433654 (XMM-Newton) to search for the presence of non-thermal X-ray emission. We found no evidence of non-thermal emission spatially coincident with the bow shocks, nonetheless, diffuse emission is detected in the vicinity of $\\zeta$ Oph. After a careful analysis of its spectral characteristics we conclude that this emission has a thermal nature with a plasma temperature of $T \\approx 2 \\times10^{6}$ K. The cometary shape of this emission seems to be in line with recent predictions of radiation-hydrodynamic models of runaway stars. The case of BD+433654 is puzzling as non-thermal emission has been reported in a previous work for this source.

  20. Non-thermal X-rays from bow shock runaways: a legacy programme for XMM-Newton

    Science.gov (United States)

    De Becker, Michael

    2013-10-01

    Massive stars ejected from their birth place, the so-called runaway massive stars, are likely to produce strong bow shocks through the interaction of the their stellar winds with the interstellar medium. Such shocks have been proven to be efficient at accelerating particles, as revealed by the identification of non-thermal radiation in a couple of objects. This large programme aims at obtaining measurements of the non-thermal X-ray flux of a carefully selected sample of bow shock runaways (BSRs), to quantify their capability to accelerate particles, in relation with their potential contribution to the production of Galactic cosmic-rays. Such an unprecedented collection of data is aimed at constituting some kind of legacy programme for XMM-Newton, before the advent of future generation X-ray observatories.

  1. Pattern Switchable Antenna System Using Inkjet-Printed Directional Bow-Tie for Bi-Direction Sensing Applications

    Directory of Open Access Journals (Sweden)

    Seung-Hyun Eom

    2015-12-01

    Full Text Available In this paper, we propose a paper-based pattern switchable antenna system using inkjet-printing technology for bi-direction sensor applications. The proposed antenna system is composed of two directional bow-tie antennas and a switching network. The switching network consists of a single-pole-double-throw (SPDT switch and a balun element. A double-sided parallel-strip line (DSPSL is employed to convert the unbalanced microstrip mode to the balanced strip mode. Two directional bow-tie antennas have different radiation patterns because of the different orientation of the reflectors and antennas. It is demonstrated from electromagnetic (EM simulation and measurement that the radiation patterns of the proposed antenna are successfully switched by the SPDT switch.

  2. Dual-Frequency Operation of Bow-Tie Microstrip Antenna%蝶形微带天线的双频工作

    Institute of Scientific and Technical Information of China (English)

    钟顺时; 张需溥

    2005-01-01

    Characteristics of a single-feed dual-frequency bow-tie microstrip antenna are studied. By using the variation method, simple formulas for resonant frequencies of the bow-tie microstrip antenna are derived. It is shown that the dual-frequency ratio can be controlled easily by choosing the parameters of the antenna. This design gives compact antenna size and simple antenna structure. Experimental results are presented, verifying the validity of the design.

  3. Investigation on Ring/Split-Ring Loaded Bow-Tie Antenna for Compactness and Notched-Band

    Science.gov (United States)

    Peng, Lin; Xie, Ji-yang; Jiang, Xing; Li, Si-min

    2016-03-01

    In this paper, a Bow-tie antenna with size reduction, impedance matching and radiation pattern improvement characteristics is designed with an encircling ring. Moreover, further size reduction is achieved by utilizing two symmetric split rings with more frequency tuning flexibility. Research found the ring loaded Bow-tie antenna (RLBA) shows better performance than the referenced Bow-tie antenna (RBA), and the mechanisms of performance improvements are also investigated and found to be the loading ring acts as two symmetric dipoles in the direction of the antenna's polarization. Then, using two symmetric split rings on the opposite side of the substrate as replacement of the encircling ring will prolong the length of the dipoles, and achieves further size reduction. The antenna is denoted as dual split ring loaded Bow-tie antenna (DSRBA). The low cutoff frequencies of RBA, RLBA and DSRBA with identical antenna size are 2.65 GHz, 2.27 GHz and 2.06 GHz, respectively. Then, the corresponding diameters of the antennas are 0.353 λc, 0.303 λc, and 0.275 λc, where λc are their corresponding wavelength of the lower cutoff frequencies. Furthermore, a notched-band is generated as a byproduct of the split rings, and it is owing to the new resonance of the overlap areas of the split rings. The notch can be used to alleviate interference of WiMAX band by carefully choosing the split rings' size. Radiation patterns of RLBA and DSRBA are also improved as current distributions of the high frequencies are trained in order by the ring/split-rings. Measurements are performed to verify the designs.

  4. Quasiparticle self-consistent GW theory of III-V nitride semiconductors: Bands, gap bowing, and effective masses

    DEFF Research Database (Denmark)

    Svane, Axel; Christensen, Niels Egede; Gorczyca, I.

    2010-01-01

    on the basis of the local approximation to density functional theory, although generally overestimated by 0.2–0.3 eV in comparison with experimental gap values. Details of the electronic energies and the effective masses including their pressure dependence are compared with available experimental information....... The band gap of InGaN2 is considerably smaller than what would be expected by linear interpolation implying a significant band gap bowing in InGaN alloys....

  5. Mountains and Tropical Circulation

    Science.gov (United States)

    Naiman, Z.; Goodman, P. J.; Krasting, J. P.; Malyshev, S.; Russell, J. L.; Stouffer, R. J.

    2015-12-01

    Observed tropical convection exhibits zonal asymmetries that strongly influence spatial precipitation patterns. The drivers of changes to this zonally-asymmetric Walker circulation on decadal and longer timescales have been the focus of significant recent research. Here we use two state-of-the-art earth system models to explore the impact of earth's mountains on the Walker circulation. When all land-surface topography is removed, the Walker circulation weakens by 33-59%. There is a ~30% decrease in global, large-scale upward vertical wind velocities in the middle of the troposphere, but only minor changes in global average convective mass flux, precipitation, surface and sea-surface temperatures. The zonally symmetric Hadley circulation is also largely unchanged. Following the spatial pattern of changes to large-scale vertical wind velocities, precipitation becomes less focused over the tropics. The weakening of the Walker circulation, but not the Hadley circulation, is similar to the behavior of climate models during radiative forcing experiments: in our simulations, the weakening is associated with changes in vertical wind velocities, rather than the hydrologic cycle. These results indicate suggest that mountain heights may significantly influence the Walker circulation on geologic time scales, and observed changes in tropical precipitation over millions of years may have been forced by changes in tropical orography.

  6. Protected areas in mountains

    Directory of Open Access Journals (Sweden)

    Hamilton, L. S.

    2006-12-01

    Full Text Available

    The importance of a global Protected Areas Network in sustaining appropriate mountain development is presented in this paper. Present status of the world’s “official” Protected Areas in the UN List, and the proportion that are in mountain areas, and including international designations (World Heritage and Biosphere Reserves. Current and future challenges in the management of these special areas are also commented.



    El autor destaca la importancia de una Red Mundial de Espacios Protegidos para el desarrollo sostenible de las montañas. Comenta luego el estatus actual de las Áreas Protegidas “oficiales” del Mundo en la Lista de las Naciones Unidas y qué proporción de ellas forma parte de las montañas, sin olvidar las figuras internacionales de protección como Patrimonio de la Humanidad y Reservas de Biosfera. Para terminar, se discuten los problemas de gestión actuales y futuros de estas áreas tan especiales

  7. Deceleration of the solar wind upstream from the earth's bow shock and the origin of diffuse upstream ions

    Science.gov (United States)

    Bame, S. J.; Asbridge, J. R.; Feldman, W. C.; Gosling, J. T.; Paschmann, G.; Skopke, N.

    1980-01-01

    Observations with the Los Alamos Scientific Laboratory/Max-Planck-Institut crossed-fan solar wind ion experiment on ISEE I reveal that the solar wind is decelerated and deflected away from the direction of the earth's bow shock as it enters that portion of the upstream region populated by diffuse bow shock ions and long-period (10-60 s) waves. Typically, the average directed velocity vector changes by 7-10 km/s as it enters the wave region. At times, average speed changes as large as 25-40 km/s are observed. Superposed upon these changes in average flow speed are large amplitude (+ or - 15) fluctuations in flow speed associated with the waves themselves. The observations suggest that the solar wind deceleration is the result of momentum transfer from reflected bow shock ions to the wind via the long-period waves as the reflected ion beams go unstable. The broad angular distributions of the diffuse ions thus appear to be produced as a consequence of the disruption of reflected ion beams.

  8. ISEE-3 observations of the earth's radio continuum through the bow shock and magnetosheath and in the magnetosphere

    Science.gov (United States)

    Steinberg, J.-L.; Hoang, S.; Lacombe, C.; Zwickl, R. D.

    1988-01-01

    On October 1 1983, ISEE-3 crossed the earth's bow shock several times and entered the magnetosphere while continuously recording the nonthermal continuum (NTC) radio emission which is generated inside the magnetosphere. The effects of the solar wind, the bow shock, the magnetosheath, and the magnetopause on the propagation of the NTC are studied. On that day it is found that: (1) the relative values of the NTC low frequency cut-off in the solar wind and in the magnetosheath is due to an unusually high density overshoot in the bow shock, 7 to 11 times the solar wind density; (2) refraction at the interface between the magnetosheath and the solar wind can explain most of the decrease in the source angular size when the observer travels away from the earth; (3) plasma density irregularities in the magnetosheath cause considerable scattering of the NTC, and this effect gives a large apparent size to the NTC source when observed from inside the magnetosheath; and (4) the apparent source is also relatively large inside the magnetosphere, probably due to an approach to ray isotropy caused by oblique reflections from the magnetopause.

  9. IR-excesses around nearby Lambda Boo stars are caused by debris disks rather than ISM bow waves

    CERN Document Server

    Draper, Zachary H; Kennedy, Grant M; Wyatt, Mark C; Venn, Kim A; Sibthorpe, Bruce

    2015-01-01

    Lambda Boo stars are predominately A-type stars with solar abundant C, N, O, and S, but up to 2 dex underabundances of refractory elements. The stars' unusual surface abundances could be due to a selective accretion of volatile gas over dust. It has been proposed that there is a correlation between the Lambda Boo phenomenon and IR-excesses which are the result of a debris disk or interstellar medium (ISM) interaction providing the accreting material. We observe 70 or 100 and 160 $\\mu$m excess emission around 9 confirmed Lambda Boo stars with the Herschel Space Observatory, to differentiate whether the dust emission is from a debris disk or an ISM bow wave. We find that 3/9 stars observed host well resolved debris disks. While the remaining 6/9 are not resolved, they are inconsistent with an ISM bow wave based on the dust emission being more compact for its temperature and predicted bow wave models produce hotter emission than what is observed. We find the incidence of bright IR-excesses around Lambda Boo star...

  10. Search for Diffuse X-rays from the Bow Shock Region of Runaway Star BD+43$^\\circ$3654 with Suzaku

    CERN Document Server

    Terada, Yukikatsu; Bamba, Aya; Yamazaki, Ryo; Kouzu, Tomomi; Koyama, Shu; Seta, Hiromi

    2012-01-01

    The bow shocks of runaway stars with strong stellar winds of over 2000 km s$^{-1}$ can serve as particle acceleration sites. The conversion from stellar wind luminosity into particle acceleration power has an efficiency of the same order of magnitude as those in supernova remnants, based on the radio emission from the bow shock region of runaway star BD+43$^\\circ$3654 \\citep{Benaglia10}.If this object exhibits typical characteristics, then runaway star systems can contribute a non-negligible fraction of Galactic cosmic-ray electrons. To constrain the maximum energy of accelerated particles from measurements of possible non-thermal emissions in the X-ray band, Suzaku observed BD+43$^\\circ$3654 in April 2011 with an exposure of 99 ks. Because the onboard instruments have a stable and low background level, Suzaku detected a possible enhancement over the background of $7.6\\pm 3.4$ cnt arcmin$^{-2}$ at the bow shock region, where the error represents the 3 sigma statistics only. However, the excess is not signific...

  11. mitochondrion Spermophilus musicus (Caucasian mountain ground [

    Lifescience Database Archive (English)

    Full Text Available mitochondrion Spermophilus musicus (Caucasian mountain ground [gbrod]: 2 CDS's (760... of codon usage for each CDS (format) Homepage mitochondrion Spermophilus musicus (Caucasian mountain ground ...

  12. YUCCA MOUNTAIN PROJECT - A BRIEFING --

    Energy Technology Data Exchange (ETDEWEB)

    NA

    2003-08-05

    This report has the following articles: Nuclear waste--a long-term national problem; Spent nuclear fuel; High-level radioactive waste; Radioactivity and the environment; Current storage methods; Disposal options; U.S. policy on nuclear waste; The focus on Yucca Mountain; The purpose and scope of the Yucca Mountain Project; The approach for permanently disposing of waste; The scientific studies at Yucca Mountain; The proposed design for a repository at Yucca Mountain; Natural and engineered barriers would work together to isolate waste; Meticulous science and technology to protect people and the environment; Licensing a repository; Transporting waste to a permanent repository; The Environmental Impact Statement for a repository; Current status of the Yucca Mountain Project; and Further information available on the Internet.

  13. Computational fluid dynamics based bulbous bow optimization using a genetic algorithm

    Science.gov (United States)

    Mahmood, Shahid; Huang, Debo

    2012-09-01

    Computational fluid dynamics (CFD) plays a major role in predicting the flow behavior of a ship. With the development of fast computers and robust CFD software, CFD has become an important tool for designers and engineers in the ship industry. In this paper, the hull form of a ship was optimized for total resistance using CFD as a calculation tool and a genetic algorithm as an optimization tool. CFD based optimization consists of major steps involving automatic generation of geometry based on design parameters, automatic generation of mesh, automatic analysis of fluid flow to calculate the required objective/cost function, and finally an optimization tool to evaluate the cost for optimization. In this paper, integration of a genetic algorithm program, written in MATLAB, was carried out with the geometry and meshing software GAMBIT and CFD analysis software FLUENT. Different geometries of additive bulbous bow were incorporated in the original hull based on design parameters. These design variables were optimized to achieve a minimum cost function of "total resistance". Integration of a genetic algorithm with CFD tools proves to be effective for hull form optimization.

  14. Experimental Study on Behavior of Bow-tie Tree Generation by Using Heavy Water

    Science.gov (United States)

    Kumazawa, Takao; Nakagawa, Wataru; Tsurumaru, Hidekazu

    Bow-tie tree (BTT) generated from contaminant, e.g., metal, carbon, amber(over cured resin) or void in insulator is a significant deterioration factor of XLPE power cable. However, essential role of water in generation and progress of BTT is not yet sufficiently cleared. In order to investigate the role of water we paid attention to difference in chemical properties of light water (H2O) and heavy water (D2O), moreover we evaluated influence of isotopic effect due to hydrogen and deuterium on behavior of BTT generation. In accelerated aging test the number of BTT in XLPE sample, in which copper powder of 500ppm was contaminated as BTT cores, dipped in heavy water (D2O:100wt%) decreased to one third compared with light water(D2O:0wt%). Furthermore, the maximum length of BTT decreased with increase in concentration of heavy water. The experimental results show that heavy water exerted a depression effect on generation and progress of BTT. We considered that the depression effect due to hydrogen isotope appeared by inhibiting ionization and elution of BTT cores, because salt-solubility and ionic mobility of heavy water are about 15 to 20% smaller than those of light water. Therefore, the essential role of water seemed to be production and transport of ions in XLPE.

  15. Influence of Water and Ion Diffusion on Generation and Progress of Bow-tie Tree

    Science.gov (United States)

    Kumazawa, Takao; Nakagawa, Wataru; Tsurumaru, Hidekazu

    Bow-tie tree(BTT) generated from contaminant, e.g., metal, carbon, amber(over cured resin) or void is a deterioration factor of XLPE cable. In particular, BTT in contact with inner or outer semi-conductive shield could significantly lower residual AC breakdown voltage of HV power cable. To evaluate influence of water and ion diffusion on generation and progress of BTT, we investigated relationship between water content of XLPE and the generation of BTT by various accelerated aging. The number of BTT in XLPE samples with accelerated aging under open condition, involving evaporation of water in which samples were immersed, was very large compared with closed condition. Furthermore, when samples were intermittently immersed in water, the number of BTT in samples was large compared with samples immersed continuously. In these experiments the generation of BTT seemed to have nothing to do with changes in water content before and after accelerated aging. Therefore, it was suggested that diffusion of ions rather than water in XLPE played an important role in the generation of BTT.

  16. Relativistic Electrons Produced by Foreshock Disturbances Observed Upstream of Earth's Bow Shock

    Science.gov (United States)

    Wilson, L. B.; Sibeck, D. G.; Turner, D. L.; Osmane, A.; Caprioli, D.; Angelopoulos, V.

    2016-11-01

    Charged particles can be reflected and accelerated by strong (i.e., high Mach number) astrophysical collisionless shock waves, streaming away to form a foreshock region in communication with the shock. Foreshocks are primarily populated by suprathermal ions that can generate foreshock disturbances—large-scale (i.e., tens to thousands of thermal ion Larmor radii), transient (˜5 - 10 per day ) structures. They have recently been found to accelerate ions to energies of several keV. Although electrons in Saturn's high Mach number (M >40 ) bow shock can be accelerated to relativistic energies (nearly 1000 keV), it has hitherto been thought impossible to accelerate electrons beyond a few tens of keV at Earth's low Mach number (1 ≤M events. These relativistic electrons are not associated with any solar or magnetospheric activity. Further, due to their relatively small Larmor radii (compared to magnetic gradient scale lengths) and large thermal speeds (compared to shock speeds), no known shock acceleration mechanism can energize thermal electrons up to relativistic energies. The discovery of relativistic electrons associated with foreshock structures commonly generated in astrophysical shocks could provide a new paradigm for electron injections and acceleration in collisionless plasmas.

  17. Band gap bowing in NixMg1-xO

    Science.gov (United States)

    Niedermeier, Christian A.; Råsander, Mikael; Rhode, Sneha; Kachkanov, Vyacheslav; Zou, Bin; Alford, Neil; Moram, Michelle A.

    2016-08-01

    Epitaxial transparent oxide NixMg1-xO (0 ≤ x ≤ 1) thin films were grown on MgO(100) substrates by pulsed laser deposition. High-resolution synchrotron X-ray diffraction and high-resolution transmission electron microscopy analysis indicate that the thin films are compositionally and structurally homogeneous, forming a completely miscible solid solution. Nevertheless, the composition dependence of the NixMg1-xO optical band gap shows a strong non-parabolic bowing with a discontinuity at dilute NiO concentrations of x band structure and the density of states demonstrate that deep Ni 3d levels are introduced into the MgO band gap, which significantly reduce the fundamental gap as confirmed by optical absorption spectra. These states broaden into a Ni 3d-derived conduction band for x > 0.074 and account for the anomalously large band gap narrowing in the NixMg1-xO solid solution system.

  18. Non-thermal Electrons at the Earth's Bow Shock: A `Gradual' Event

    CERN Document Server

    Oka, M; Fujimoto, M; Matsui, H; Kasaba, Y; Saitô, Y; Kojima, H; Matsumoto, H; Mukai, T

    2008-01-01

    Earth's bow shock is known to produce non-thermal electrons which are generally observed as a `spike' in their flux profile. Here, in this paper, we present an analysis of electron and whistler wave properties for a quasi-perpendicular shock crossing that is supercritical, but subcritical to the so-called whistler critical Mach number, M$^w_{\\rm crit}$, above which whistler waves cannot propagate upstream. We have found that the amplitudes of whistler waves increased exponentially as a function of time prior to the shock encounter, while the suprathermal ($>$ 2 keV) electron flux similarly increased with time, although with differing $e$-folding time scales. Comparison of the electron energy spectrum measured within the ramp with predictions from diffusive shock acceleration theory was poor, but the variation of pitch angle distribution showed scattering of non-thermal electrons in the upstream region. While not finding a specific mechanism to account for the electron diffusion, we suggest that the whistlers ...

  19. Computational Fluid Dynamics Based Bulbous Bow Optimization Using a Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    Shahid Mahmood; Debo Huang

    2012-01-01

    Computational fluid dynamics (CFD) plays a major role in predicting the flow behavior of a ship.With the development of fast computers and robust CFD software,CFD has become an important tool for designers and engineers in the ship industry.In this paper,the hull form of a ship was optimized for total resistance using CFD as a calculation tool and a genetic algorithm as an optimization tool.CFD based optimization consists of major steps involving automatic generation of geometry based on design parameters,automatic generation of mesh,automatic analysis of fluid flow to calculate the required objective/cost function,and finally an optimization tool to evaluate the cost for optimization.In this paper,integration of a genetic algorithm program,written in MATLAB,was carried out with the geometry and meshing software GAMBIT and CFD analysis software FLUENT.Different geometries of additive bulbous bow were incorporated in the original hull based on design parameters.These design variables were optimized to achieve a minimum cost function of “total resistance”.Integration of a genetic algorithm with CFD tools proves to be effective for hull form optimization.

  20. Postural stability, clicker reaction time and bow draw force predict performance in elite recurve archery.

    Science.gov (United States)

    Spratford, Wayne; Campbell, Rhiannon

    2017-02-14

    Recurve archery is an Olympic sport that requires extreme precision, upper body strength and endurance. The purpose of this research was to quantify how postural stability variables both pre- and post-arrow release, draw force, flight time, arrow length and clicker reaction time, collectively, impacted on the performance or scoring outcomes in elite recurve archery athletes. Thirty-nine elite-level recurve archers (23 male and 16 female; mean age = 24.7 ± 7.3 years) from four different countries volunteered to participate in this study prior to competing at a World Cup event. An AMTI force platform (1000Hz) was used to obtain centre of pressure (COP) measurements 1s prior to arrow release and 0.5s post-arrow release. High-speed footage (200Hz) allowed for calculation of arrow flight time and score. Results identified clicker reaction time, draw force and maximum sway speed as the variables that best predicted shot performance. Specifically, reduced clicker reaction time, greater bow draw force and reduced postural sway speed post-arrow release were predictors of higher scoring shots. It is suggested that future research should focus on investigating shoulder muscle tremors at full draw in relation to clicker reaction time, and the effect of upper body strength interventions (specifically targeting the musculature around the shoulder girdle) on performance in recurve archers.

  1. The Parametric Study and Fine-Tuning of Bow-Tie Slot Antenna with Loaded Stub

    Science.gov (United States)

    2017-01-01

    A printed Bow-Tie slot antenna with loaded stub is proposed and the effects of changing the dimensions of the slot area, the stub and load sizes are considered in this paper. These parameters have a considerable effect on the antenna characteristics as well as its performance. An in-depth parametric study of these dimensions is presented. This paper proposes the necessary conditions for initial approximation of dimensions needed to design this antenna. In order to achieve the desired performance of the antenna fine tuning of all sizes of these parameters is required. The parametric studies used in this paper provide proper trends for initiation and tuning the design. A prototype of the antenna for 1.7GHz to 2.6GHz band is fabricated. Measurements conducted verify that the designed antenna has wideband characteristics with 50% bandwidth around the center frequency of 2.1GHz. Conducted measurements for reflection coefficient (S11) and radiation pattern also validate our simulation results. PMID:28114354

  2. A Spectacular Bow Shock in the 11 keV Galaxy Cluster Around 3C 438

    CERN Document Server

    Emery, Deanna L; Kraft, Ralph P; Andrade-Santos, Felipe; Forman, William R; Hardcastle, Martin J; Jones, Christine

    2016-01-01

    We present results of deep 153 ks Chandra observations of the hot, 11 keV, galaxy cluster associated with the radio galaxy 3C 438. By mapping the morphology of the hot gas and analyzing its surface brightness and temperature distributions, we demonstrate the presence of a merger bow shock. We identify the presence of two jumps in surface brightness and in density located at $\\sim$400 kpc and $\\sim$800 kpc from the cluster's core. At the position of the inner jump, we detect a factor of $2.3\\pm 0.2$ density jump, while at the location of the outer jump, we detect a density drop of a factor of $3.5 \\pm 0.7$. Combining this with the temperature distribution within the cluster, we establish that the pressure of the hot gas is continuous at the 400 kpc jump, while there is a factor of $6.2 \\pm 2.8$ pressure discontinuity at 800 kpc jump. From the magnitude of the outer pressure discontinuity, using the Rankine-Hugoniot jump conditions, we determine that the sub-cluster is moving at $M = 2.3\\pm 0.5$, or approximate...

  3. Cherchez la Femme en The Ox-Bow Incident de Wellman: analizando fractales

    Directory of Open Access Journals (Sweden)

    Rose Lema

    2009-01-01

    Full Text Available Se presenta una definición sucinta de conceptos generales provenientes de la Teoría del Caos, empleados particularmente en termodinámica: fractal, autosimilaridad, bifurcación (Mandelbrot y se describe brevemente el principio de Poincaré en torno a la Teoría de los Tres cuerpos. Un método similar con las correspondientes variantes ha sido aplicado por varios estudiosos de las Humanidades, con el fin de demostrar que se puede atravesar un puente entre ideas de éstas y las demás ciencias. Segundo, se aplicó el método para estudiar los personajes femeninos del filme The Ox-Bow Incident de William Wellman, que ganara el Óscar por la mejor película en el mismo año de su producción. Por último, se argumenta que la Geometría Fractal de la Naturaleza conduce a descentralizar el rol de los cowboys que llevan a cabo el linchamiento, mientras que se centra el papel de las mujeres, y, en especial, a visualizar dos personajes femeninos virtuales, gesto que rompe con la aparente linearidad de la trama.

  4. Quantified Energy Dissipation Rates: Electromagnetic Wave Observations in the Terrestrial Bow Shock

    CERN Document Server

    Wilson, L B; Breneman, A W; Contel, O Le; Cully, C; Turner, D L; Angelopoulos, V

    2013-01-01

    We present the first quantified measure of the rate of energy dissipated per unit volume by high frequency electromagnetic waves in the transition region of the Earth's collisionless bow shock using data from the THEMIS spacecraft. Every THEMIS shock crossing examined with available wave burst data showed both low frequency ( 10 Hz) electromagnetic and electrostatic waves throughout the entire transition region and into the magnetosheath. The waves in both frequency ranges had large amplitudes, but the higher frequency waves, which are the focus of this study, showed larger contributions to both the Poynting flux and the energy dissipation rates. The higher frequency waves were identified as combinations of ion-acoustic waves, electron cyclotron drift instability driven waves, electrostatic solitary waves, and whistler mode waves. These waves were found to have: (1) amplitudes capable of exceeding dB ~ 10 nT and dE ~ 300 mV/m, though more typical values were dB ~ 0.1-1.0 nT and dE ~ 10-50 mV/m; (2) energy flu...

  5. Application of Single Spacecraft Methods to Study the Motion of the Venusian Bow Shock

    Science.gov (United States)

    Giagkiozis, Stefanos; Pope, Simon

    2016-07-01

    Collisionless shockwaves are associated with a plethora of processes throughout the universe. Supernova remnant shocks are considered one of the main mechanisms that are capable to accelerate particles at high enough energies as the ones observed in cosmic rays. It is still unknown how these shocks accelerate particle to such high energies. By studying shocks in the heliosphere in order to define as much as possible of their parameter space, we could find the answer to this question. One important collisionless shock parameter is the velocity that the shock is travelling. This velocity can be used to define the spatial scales of the shock. The spatial scale in turn is closely related to the processes that govern the energy dissipation and in turn the nature of the shock. The use of multi-spacecraft measurements are the most reliable method to determine the shock velocity. However single spacecraft measurements are often only available, particularly for planetary missions. In a previous study we examined the accuracy of some of the single spacecraft methods that have been developed. Here we apply these approaches to a series of observations of the Venusian bow shock at different locations using Venus Express magnetic field data.

  6. Experimental demonstration of bow-shock instability and its numerical analysis

    Science.gov (United States)

    Kikuchi, Y.; Ohnishi, N.; Ohtani, K.

    2016-07-01

    An experimental demonstration was carried out in a ballistic range at high Mach numbers with the low specific heat ratio gas hydrofluorocarbon HFC-134a to observe the unstable bow-shock wave generated in front of supersonic blunt objects. The shadowgraph images obtained from the experiments showed instability characteristics, in which the disturbances grow and flow downstream and the wake flow appears wavy because of the shock oscillation. Moreover, the influence of the body shape and specific heat ratio on the instability was investigated for various experimental conditions. Furthermore, the observed features, such as wave structure and disturbance amplitude, were captured by numerical simulations, and it was demonstrated that computational fluid dynamics could effectively simulate the physical instability. In addition, it was deduced that the shock instability is induced by sound emissions from the edge of the object. This inference supports the dependence of the instability on the specific heat ratio and Mach number because the shock stand-off distance is affected by these parameters and limits the sound wave propagation.

  7. The Parametric Study and Fine-Tuning of Bow-Tie Slot Antenna with Loaded Stub.

    Science.gov (United States)

    Shafiei, M M; Moghavvemi, Mahmoud; Wan Mahadi, Wan Nor Liza

    2017-01-01

    A printed Bow-Tie slot antenna with loaded stub is proposed and the effects of changing the dimensions of the slot area, the stub and load sizes are considered in this paper. These parameters have a considerable effect on the antenna characteristics as well as its performance. An in-depth parametric study of these dimensions is presented. This paper proposes the necessary conditions for initial approximation of dimensions needed to design this antenna. In order to achieve the desired performance of the antenna fine tuning of all sizes of these parameters is required. The parametric studies used in this paper provide proper trends for initiation and tuning the design. A prototype of the antenna for 1.7GHz to 2.6GHz band is fabricated. Measurements conducted verify that the designed antenna has wideband characteristics with 50% bandwidth around the center frequency of 2.1GHz. Conducted measurements for reflection coefficient (S11) and radiation pattern also validate our simulation results.

  8. ANALISA PENGARUH BENTUK LAMBUNG AXE BOW PADA KAPAL HIGH SPEED CRAFT TERHADAP HAMBATAN TOTAL

    Directory of Open Access Journals (Sweden)

    Romadhoni Oni

    2015-06-01

    Full Text Available Hambatan merupakan salah satu faktor utama yang mempengaruhi proses perancangan sebuah kapal. Kapal dengan bentuk lambung yang baik akan menghasilkan hambatan yang efisiensi sehingga operasional kapal dan pergerakan kapal lebih baik. Pada ini penelitian dilakukan dengan memodelkan kapal high speed craft tipe Crew boat panjang 38 meter, lebar 7.6 meter, tinggi 3.65 meter dan draft 1.89 meter. Selanjutnya diselidiki model lambung kapal yang menghasilkan hambatan total paling kecil menggunakan pendekatan studi numerik software (maxsuft hullspeed metode savitsky dan holtrop dan software Computational Fluid Dynamics (CFD. Hasil penelitian berdasarkan analisa numerik (Maxsuft –Hullspeed dan CFD menujukkan pada kecepatan sevice bentuk lambung model AXE Bow memiliki nilai hambatan yang lebih kecil dibandingkan model kapal planing hull chine (HPC dan rounded hull (RH. Hasil perhitungan numerik dan CFD memiliki nilai yang hampir sama pada setiap variasi model. Hasil komparisi yang dilakukan didapatkan selisih total hambatan pada kecepatan 25 knot yaitu  model HPC 1.8 kN, model HPCAB 5.2 kN, model RH 4.8 kN dan model 5.1 kN. Dari perbandingan kedua metode tersebut memiliki selisih cukup kecil yaitu  kurang dari 5%. Selain mendapatkan nilai hambatan Software CFD akan menghasilkan nilai  perbandingan gaya angkat (lift force, dan total pressure yang terdistribusi  pada permukaan model setiap variasi kecepatan.

  9. Endoparasites of Wild Rodents in Southeastern Iran

    Directory of Open Access Journals (Sweden)

    Mehdi Nateghpour

    2015-10-01

    Full Text Available Background: This study was aimed to collect wild rodents for endoparasites determination in some parts of Sistan and Baluchistan Province, southeastern Iran nearby Pakistan and Afghanistan countries.Methods: A total of 100 wild rodents were captured alive with cage traps. Various samples were collected from blood and feces, also impression smear prepared from different organs. The samples were prepared by formalin-ether or stained with Giemsa, after that were examined under microscope.Results: All the caught rodents (47 Tatera indica, 44 Meriones hurriana, 5 Gerbilus nanus and 4 Meriones libycus were studied for endoparasites emphasizing to their zoonotic aspects. Endoparasites including Spirurida,Hymenolepis diminuta, Hymenolepis nana feraterna, Trichuris trichiura, Skerjabino taenia, Trichostrongylus spp, Entamoeba muris, Chilomastix mesnili and Leishmania spp were parasitologically identified.Conclusion: Among 9 genera or species of the identified parasites at least 5 of them have zoonotic and public health importance.

  10. European mountain biodiversity

    Directory of Open Access Journals (Sweden)

    Nagy, Jennifer

    1998-12-01

    Full Text Available This paper, originally prepared as a discussion document for the ESF Exploratory Workshop «Trends in European Mountain Biodiversity - Research Planning Workshop», provides an overview of current mountain biodiversity research in Europe. It discusses (a biogeographical trends, (b the general properties of biodiversity, (c environmental factors and the regulation of biodiversity with respect to ecosystem function, (d the results of research on mountain freshwater ecosystems, and (e climate change and air pollution dominated environmental interactions.- The section on biogeographical trends highlights the importance of altitude and latitude on biodiversity. The implications of the existence of different scales over the different levels of biodiversity and across organism groups are emphasised as an inherent complex property of biodiversity. The discussion on ecosystem function and the regulation of biodiversity covers the role of environmental factors, productivity, perturbation, species migration and dispersal, and species interactions in the maintenance of biodiversity. Regional and long-term temporal patterns are also discussed. A section on the relatively overlooked topic of mountain freshwater ecosystems is presented before the final topic on the implications of recent climate change and air pollution for mountain biodiversity.

    [fr] Ce document a été préparé à l'origine comme une base de discussion pour «ESF Exploratory Workshop» intitulé «Trends in European Mountain Biodiversity - Research Planning Workshop»; il apporte une vue d'ensemble sur les recherches actuelles portant sur la biodiversité des montagnes en Europe. On y discute les (a traits biogéographiques, (b les caractéristiques générales- de la biodiversité, (c les facteurs environnementaux et la régulation de la biodiversité par rapport à la fonction des écosystèmes, (d les résultats des études sur les écosystèmes aquatiques des montagnes et (e les

  11. Ks- and Lp-band polarimetry on stellar and bow-shock sources in the Galactic center

    Science.gov (United States)

    Buchholz, R. M.; Witzel, G.; Schödel, R.; Eckart, A.

    2013-09-01

    Context. Infrared observations of the Galactic center (GC) provide a unique opportunity to study stellar and bow-shock polarization effects in a dusty environment. Aims: The goals of this work are to present new Ks- and Lp-band polarimetry on an unprecedented number of sources in the central parsec of the GC, thereby expanding our previous results in the H- and Ks-bands. Methods: We use AO-assisted Ks- and Lp-band observations, obtained at the ESO VLT. High precision photometry and the new polarimetric calibration method for NACO allow us to map the polarization in a region of 8'' × 25'' (Ks) resp. 26'' × 28'' (Lp). These are the first polarimetric observations of the GC in the Lp-band in 30 years, with vastly improved spatial resolution compared to previous results. This allows resolved polarimetry on bright bow-shock sources in this area for the first time at this wavelength. Results: We find foreground polarization to be largely parallel to the Galactic plane (Ks-band: 6.1% at 20°, Lp-band: 4.5% at 20°), in good agreement with our previous findings and with older results. The previously described Lp-band excess in the foregound polarization towards the GC could be confirmed here for a much larger number of sources. The bow-shock sources contained in the FOV seem to show a different relation between the polarization in the observed wavelength bands than what was determined for the foreground. This points to the different relevant polarization mechanisms. The resolved polarization patterns of IRS 5 and 10W match the findings we presented earlier for IRS 1W. Additionally, intrinsic Lp-band polarization was measured for IRS 1W and 21, as well as for other, less prominent mid-infrared-excess sources (IRS 2S, 2L, 5NE). The new data offer support for the presumed bow-shock nature of several of these sources (1W, 5, 5NE, 10W, 21) and for the model of bow-shock polarization presented in our last work. Tables 1 and 2 are available in electronic form at http

  12. Fire history of southeastern Glacier National Park: Missouri River Drainage

    Science.gov (United States)

    Barrett, Stephen W.

    1993-01-01

    In 1982, Glacier National Park (GNP) initiated long-term studies to document the fire history of all forested lands in the 410,000 ha. park. To date, studies have been conducted for GNP west of the Continental Divide (Barrett et al. 1991), roughly half of the total park area. These and other fire history studies in the Northern Rockies (Arno 1976, Sneck 1977, Arno 1980, Romme 1982, Romme and Despain 1989, Barrett and Arno 1991, Barrett 1993a, Barrett 1993b) have shown that fire history data can be an integral element of fire management planning, particularly wen natiral fire plans are being developed for parks and wilderness. The value of site specific fire history data is apparent when considering study results for lodgepole pin (Pinus contorta var. latifolia) forests. Lodgepole pine is a major subalpine type in the Northern Rockies and such stands experiences a wide range of presettlement fire patterns. On relatively warm-dry sites at lower elevations, such as in GNP's North Fork drainage (Barrett et al. 1991), short to moderately long interval (25-150 yr) fires occurred in a mixed severity pattern ranging from non-lethal underburns to total stand replacement (Arno 1976, Sneck 1977, Barrett and Arno 1991). Markedly different fire history occurred at high elevation lodgepole pine stands on highly unproductive sites, such as on Yellowstone National Park's (YNP) subalpine plateau. Romme (1982) found that, on some sites, stand replacing fires recurred after very long intervals (300-400 yr), and that non-lethal surface fires were rare. For somewhat more productive sites in the Absaroka Mountains in YNP, Barrett (1993a) estimated a 200 year mean replacement interval, in a pattern similar to that found in steep mountain terrain elsewhere, such as in the Middle Fork Flathead River drainage (Barrett et al. 1991, Sneck 1977). Aside from post-1900 written records (ayres 1900; fire atlas data on file, GNP Archives Div. and GNP Resources Mgt. Div.), little fire history

  13. Iron Mountain Electromagnetic Results

    Energy Technology Data Exchange (ETDEWEB)

    Gail Heath

    2012-07-01

    Iron Mountain Mine is located seventeen miles northwest of Redding, CA. After the completion of mining in early 1960s, the mine workings have been exposed to environmental elements which have resulted in degradation in water quality in the surrounding water sheds. In 1985, the EPA plugged ore stoops in many of the accessible mine drifts in an attempt to restrict water flow through the mine workings. During this process little data was gathered on the orientation of the stoops and construction of the plugs. During the last 25 years, plugs have begun to deteriorate and allow acidic waters from the upper workings to flow out of the mine. A team from Idaho National Laboratory (INL) performed geophysical surveys on a single mine drift and 3 concrete plugs. The project goal was to evaluate several geophysical methods to determine competence of the concrete plugs and orientation of the stopes.

  14. Geology at Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-05-01

    Both advocates and critics disagree on the significance and interpretation of critical geological features which bear on the safety and suitability of Yucca Mountain as a site for the construction of a high-level radioactive waste repository. Critics believe that there is sufficient geological evidence to rule the site unsuitable for further investigation. Some advocates claim that there is insufficient data and that investigations are incomplete, while others claim that the site is free of major obstacles. We have expanded our efforts to include both the critical evaluations of existing geological and geochemical data and the collection of field data and samples for the purpose of preparing scientific papers for submittal to journals. Summaries of the critical reviews are presented in this paper.

  15. Glacial effects limiting mountain height.

    Science.gov (United States)

    Egholm, D L; Nielsen, S B; Pedersen, V K; Lesemann, J-E

    2009-08-13

    The height of mountain ranges reflects the balance between tectonic rock uplift, crustal strength and surface denudation. Tectonic deformation and surface denudation are interdependent, however, and feedback mechanisms-in particular, the potential link to climate-are subjects of intense debate. Spatial variations in fluvial denudation rate caused by precipitation gradients are known to provide first-order controls on mountain range width, crustal deformation rates and rock uplift. Moreover, limits to crustal strength are thought to constrain the maximum elevation of large continental plateaus, such as those in Tibet and the central Andes. There are indications that the general height of mountain ranges is also directly influenced by the extent of glaciation through an efficient denudation mechanism known as the glacial buzzsaw. Here we use a global analysis of topography and show that variations in maximum mountain height correlate closely with climate-controlled gradients in snowline altitude for many high mountain ranges across orogenic ages and tectonic styles. With the aid of a numerical model, we further demonstrate how a combination of erosional destruction of topography above the snowline by glacier-sliding and commensurate isostatic landscape uplift caused by erosional unloading can explain observations of maximum mountain height by driving elevations towards an altitude window just below the snowline. The model thereby self-consistently produces the hypsometric signature of the glacial buzzsaw, and suggests that differences in the height of mountain ranges mainly reflect variations in local climate rather than tectonic forces.

  16. Variation and Trends of Landscape Dynamics, Land Surface Phenology and Net Primary Production of the Appalachian Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yeqiao; Zhao, Jianjun; Zhou, Yuyu; Zhang, Hongyan

    2012-12-15

    The gradients of the Appalachian Mountains in elevations and latitudes provide a unique regional perspective of landscape variations in the eastern United States and a section of the southeastern Canada. This study reveals patterns and trends of landscape dynamics, land surface phenology and ecosystem production along the Appalachian Mountains using time series data from Global Inventory Modeling and Mapping Studies (GIMMS) and AVHRR Global Production Efficiency Model (GloPEM) datasets. We analyzed the spatial and temporal patterns of Normalized Difference Vegetation Index (NDVI), length of growing season (LOS) and net primary production (NPP) of selected ecoregions along the Appalachian Mountains regions. We compared the results out of the Appalachian Mountains regions in different spatial contexts including the North America and the Appalachian Trail corridor area. To reveal latitudinal variations we analyzed data and compared the results between 30°N-40°N and 40°N-50°N latitudes. The result revealed significant decreases in annual peak NDVI in the Appalachian Mountains regions. The trend for the Appalachian Mountains regions was -0.0018 (R2=0.55, P<0.0001) NDVI unit decrease per year during 25 years between 1982 and 2006. The LOS had prolonged 0.3 day yr-1 during 25 years over the Appalachian Mountains regions. The NPP increased by 2.68 gC m-2yr-2 in Appalachian Mountains regions from 1981 to 2000. The comparison with the North America reveals the effects of topography and ecosystem compositions of the Appalachian Mountains. The comparison with the Appalachian Trail corridor area provides a regional mega-transect view of the measured variables.

  17. The potential of energy farming in the southeastern California desert

    Science.gov (United States)

    Lew, V.

    1980-04-01

    The use of energy forms to provide future sources of energy for California is considered. Marginal desert lands in southeastern California are proposed for the siting of energy farms using acacia, eucalyptus, euphorbia, guayule, jojoba, mesquite, or tamarisk.

  18. Southeastern Cooperative Wildlife Disease Study, Santee National Wildlife Refuge, 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is an unpublished report by the Southeastern Cooperative Wildlife Disease Study of the Parasitology College of Veterinary Medicine, The University of Georgia....

  19. Southeastern Cooperative Wildlife Disease Study, 1998 and 2004

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Southeastern Cooperative Wildlife Disease Study for white-tailed deer, performed in 1998 and 2004 by the College of Veterinary Medicine of The University of Georgia.

  20. 27 CFR 9.80 - York Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false York Mountain. 9.80... Mountain. (a) Name. The name of the viticultural area described in this section is “York Mountain.” (b) Approved map. The approved map for the York Mountain viticultural area is the U.S.G.S. map entitled...

  1. 27 CFR 9.108 - Ozark Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ozark Mountain. 9.108... Ozark Mountain. (a) Name. The name of the viticultural area described in this section is “Ozark Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of Ozark Mountain...

  2. 27 CFR 9.55 - Bell Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bell Mountain. 9.55... Mountain. (a) Name. The name of the viticultural area described in this section is “Bell Mountain.” (b) Approved map. The appropriate map for determining the boundaries of the Bell Mountain viticultural area...

  3. 27 CFR 9.167 - Red Mountain

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Red Mountain 9.167 Section... Mountain (a) Name. The name of the viticultural area described in this section is “Red Mountain.” (b) Approved maps. The appropriate map for determining the boundaries of the Red Mountain viticultural area...

  4. Characterization of contemporary aeolian dust deposition on mountain glaciers of western China

    Institute of Scientific and Technical Information of China (English)

    JianZhong Xu; ShiChang Kang; ShuGui Hou; QiangGong Zhang; Jie Huang; CunDe Xiao; JiaWen Ren; DaHe Qin

    2016-01-01

    From 2008 to 2010, a total of 15 snow pit samples were collected from 13 mountain glaciers in western China. In this study these samples are used to determine the spatial distribution of insoluble particle concentrations and dust deposition fluxes in western China. The results show that the mass concentrations of insoluble particles exhibit high spatial variation and strongly decrease (by a factor of approximately 50) from the north (Tienshan Mountains) to the south (Himalayas). However, the insoluble particles concentrations at the southeastern Tibetan Plateau (TP) sites are also high and ap-proximately 30 times greater than those in the Himalayas. The spatial distribution of the dust flux is similar to that of the mass concentrations; however, the high dust deposition rate in the southeastern TP is very significant as a result of the extensive snow accumulation (precipitation) in this region. The average sizes of the insoluble particles at each site generally exhibit bimodal distributions with peaks at approximately 5 µm and 10 µm, which can be explained as re-sulting from dust emissions from regional and local sources, respectively. The enrichment factors for most of the ele-ments measured in insoluble particles are less than 10 at all of the study sites, indicating primarily crustal sources. However, the sites located in the peripheral mountains of western China, such as the Tienshan Mountains and the Himalayas, are characterized by high levels of certain enrichment elements (e.g., Cu, Zn, Cr, and V) indicative of sources related to the long-range transport of pollutants.

  5. Hydrology of the Upper Malad River basin, southeastern Idaho

    Science.gov (United States)

    Pluhowski, Edward J.

    1970-01-01

    The report area comprises 485 square miles in the Basin and Range physiographic province. It includes most of eastern' Oneida County and parts of Franklin, Bannock, and Power Counties of southeastern Idaho. Relief is about 5,000 feet; the floor of the Malad Valley is at an average altitude of about 4,400 feet. Agriculture is, by far, ,the principal economic .activity. In 1960 the population of the upper Malad River basin was about 3,600, of which about 60 percent resided in Malad City, the county seat of Oneida County. The climate is semiarid throughout the Malad Valley and its principal tributary valleys; ,above 6,500 feet the climate is subhumid. Annual precipitation ranges from about 13 inches in the lower Malad Valley to more than 30 inches on the highest peaks of the Bannock and Malad ranges. Owing to ,the normally clear atmospheric conditions, large daily and seasonal temperature fluctuations are common. Topography, distance from the Pacific Ocean, .and the general atmospheric circulation are the principal factors governing the climate of the Malad River basin. The westerlies transport moisture from the P.acific Ocean toward southeastern Idaho. The north-south tren4ing mountains flanking the basin are oriented orthogonally to the moisture flux so that they are very effective in removing precipitable water from the air. A minimum uplift of 6,000 feet is required to transport moisture from the Pacific source region; accordingly, most air masses are desiccated long before they reach the Malad basin. Heaviest precipitation is generally associated with steep pressure gradients in the midtroposphere that are so oriented as to cause a deep landward penetration of moisture from the Pacific Ocean. Annual water yields in the project area range from about 0.8 inch in the, lower Malad Valley to more than 19 inches on the high peaks north and east of Malad City. The mean annual water yield for the entire basin is 4 inches, or about 115,000 acre-feet. Evaporation is

  6. H2S in the L1157-B1 bow shock

    Science.gov (United States)

    Holdship, Jonathan; Viti, Serena; Jimenez-Serra, Izaskun; Lefloch, Bertrand; Codella, Claudio; Podio, Linda; Benedettini, Milena; Fontani, Francesco; Bachiller, Rafael; Tafalla, Mario; Ceccarelli, Cecilia

    2016-11-01

    Sulphur-bearing molecules are highly reactive in the gas phase of the interstellar medium. However, the form in which most of the sulphur is locked on to interstellar dust grains is unknown. By taking advantage of the short time-scales of shocks in young molecular outflows, one could track back the main form of sulphur in the ices. In this paper, six transitions of H2S and its isotopologues in the L1157-B1 bow shock have been detected using data from the Herschel-Chemical HErschel Surveys of Star forming regions survey and the IRAM-30m Astrochemical Surveys At IRAM large programme. These detections are used to calculate the properties of H2S gas in L1157-B1 through use of a rotation diagram and to explore the possible carriers of sulphur on the grains. The isotopologue detections allow the first calculation of the H2S deuteration fraction in an outflow from a low-mass protostar. The fractional abundance of H2S in the region is found to be 6.0 × 10-7 and the deuteration fraction is 2 × 10-2. In order to investigate the form of sulphur on the grains, a chemical model is run with four different networks, each with different branching ratios for the freeze out of sulphur-bearing species into molecules such as OCS and H2S. It is found that the model best fits the data when at least half of each sulphur-bearing species hydrogenates when freezing. We therefore conclude that a significant fraction of sulphur in L1157-B1 is likely to be locked in H2S on the grains.

  7. Magnetic Field Orientation Effects on the Standoff Distance of Earth's Bow Shock

    Science.gov (United States)

    Cairns, Iver H.; Lyon, J. G.

    1996-01-01

    Three-dimensional, global MHD simulations of solar wind flow onto a prescribed magnetopause obstacle are used to show that a bow shock's nose location a(sub s), and the relative subsolar magnetosheath thickness Delta(sub ms)/a(sub mp) are strong functions of the IMF cone angle theta (between v(sub sw) and B(sub sw)) and the Alfven Mach number M(sub A). For a given M(sub A) the shock is more distant for higher theta (restricted to the interval 0-90deg by symmetries), while a(sub s)/a(sub mp) and Delta(sub ms/a(sub mp) increase with decreasing M(sub A) for theta greater than or approximately 20deg but decrease with decreasing M(sub A) for theta approximately Odeg. Large differences in Delta(sub ms/a(sub mp) are predicted between theta = Odeg and 90deg at low M(sub A), with smaller differences remaining even at M(sub A) approximately 10. The theta = Odeg results confirm and extend the previous work of Spreiter and Rizzi [1974]. The simulations show that successful models for the subsolar shock location cannot subsume the dependences on M(sub A) and theta into a sole dependence on M(ms). Instead, they confirm a recent prediction [Cairns and Grabbe, 1994] that a(sub s)/a(sub mp) and Delta(sub ms)/a(sub mp) should depend strongly on theta and M(sub A) for M(sub A) less than or approximately 10 (as well as on other MHD variables). Detailed comparisons between theory and data remain to be done. However, preliminary comparisons show good agreement, with distant shock locations found for low M(sub A) and large theta greater than or approximately 45deg and closer locations found for theta less than or approximately 20deg even at M/A approximately 8.

  8. The location of planetary bow shocks: A critical overview of theory and observations

    Science.gov (United States)

    Spreiter, J. R.; Stahara, S. S.

    1995-01-01

    A bow shock (BS has been observed in the collisionless solar wind upstream of every planet except Pluto, which has yet to be visited by a spacecraft. They are all of similar character, but their size relative to the planet varies widely, e.g., the planeto-centric distance to the BS nose ranges from about 1.4 R(sub V) for Venus to 88 R(sub J) or more for Jupiter. Comparisons are reviewed that show its location may be represented satisfactorily by a gasdynamic (GD) model, provided the properties of the solar wind and planetary magnetic field and ionosphere are known and used as input in the application. Factors that determine the location are discussed, and examples are presented to illustrate effects of their variation, including which part of a BS is influenced by a local variation of the magneto/ionopause (MIP) shape. The interplanetary magnetic field (IMF) has no influence on the BS location in the GD model, but is shown to have a small effect in corresponding solutions of the basic MHD model from which the GD model is derived as the limit for weak IMF. Nearly all GD and MHD solutions are for steady flow, but a solution for unsteady flow associated with the passage of an interplanetary shock is also presented. It shows that the BS moves rapidly from its initial to final location, e.g., in about minute for the earth. Since many changes in the solar wind occur over longer intervals, these results help explain the success of quasi-stationary solutions in modeling the BS in time-varying solar wind flows.

  9. Monazite deposits of the southeastern Atlantic States

    Science.gov (United States)

    Mertie, John Beaver

    1953-01-01

    Monazite, a phosphate of the rare earths, is the principal mineral from which the cerium earths and thorium are obtained. Fluviatile monazite placers were mined in the Piedmont province of North and South Carolina from 1887 to 1911, and again intermittently from 1915 to 1917; but the principal sources In recent years have been the beach placers of India and Brazil. In 1946, an embargo was placed on the exportation of Indian monazite, and the Brazilian production has not increased materially to replace this loss. Accordingly monazite in recent years has become a scarce commodity. The principal domestic sources from which monazite may be recovered commercially are in Idaho and in the Piedmont province of the southeastern States. Some monazite is now being produced in Idaho, and a small output is being recovered as a byproduct of heavy mineral mining in Florida. The southeastern placers were not exhausted by the earlier mining and new deposits have been discovered; but production from this region awaits adequate exploration. The country rock of the southeastern Piedmont province is a complex assemblage of metamorphic and igneous rocks. The monazite occurs in two belts. A western belt has been traced from east-central Virginia for 600 miles southwestward into Alabama; and an eastern belt has been traced from the vicinity of Fredericksburg, Va., south-southwestward for 200 miles into North Carolina. Monazite-bearing rocks near. Rion, S. C., appear to indicate a southwestward continuation of the eastern belt. The western, or principal belt, includes the placers that were formerly mined in North and South Carolina. These placers were sampled, and the monazite was separated from the best of the samples, for mineralogical and chemical analysis. The tabulated results show a mean tenor, in the headwater placers of highest grade, of 8.4 pounds of monazite to the cubic yard. Farther downstream where mining must be done to obtain larger yardages, the tenor will be much lower

  10. The Table Mountain Field Site

    Data.gov (United States)

    Federal Laboratory Consortium — The Table Mountain Field Site, located north of Boulder, Colorado, is designated as an area where the magnitude of strong, external signals is restricted (by State...

  11. The Dilemma of Mountain Roads

    Science.gov (United States)

    Mountain roads and trails are proliferating throughout developing Southeast Asia with severe but largely unrecognized long-term consequences related to effects of landslides and surface erosion on communities and downstream resources.

  12. A mountain of millipedes IV

    DEFF Research Database (Denmark)

    Enghoff, Henrik

    2016-01-01

    Two species of the genus Prionopetalum Attems, 1909, are recorded from the Udzungwa Mountains: P. asperginis sp. nov. and P. kraepelini (Attems, 1896). Prionopetalum stuhlmanni Attems, 1914, is synonymized under P. kraepelini. Odontopyge fasciata Attems, 1896, is transferred from Prionopetalum...

  13. THE MOST SUCCE SSFUL MOUNTAINEERS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Tsering Dorje:I Dream of Climbing Mt. Qomolangma Carrying the Olympic Torch Tsering Dorje,the oldest of the Tibetan professional mountaineers,has successfully reached a total of fourteen of the world's highest mountain summits.His companions jokingly refer to him as"Aku"(meaning"uncle"in Tibetan).However, acting as an uncle,he has to shoulder the responsibilities of team leader to take care of the others.

  14. The seed plant flora of the Mount Jinggangshan region, southeastern China.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available The Mount Jinggangshan region is located between Jiangxi and Hunan provinces in southeastern China in the central section of the Luoxiao Mountains. A detailed investigation of Mount Jinggangshan region shows that the seed plant flora comprises 2,958 species in 1,003 genera and 210 families (Engler's system adjusted according to Zhengyi Wu's concept. Among them, 23 species of gymnospermae belong to 17 genera and 9 families, and 2,935 species of angiosperms are in 986 genera and 201 families. Moreover, they can also be sorted into woody plants (350 genera and 1,295 species and herbaceous plants (653 genera and 1,663 species. The dominant families are mainly Fagaceae, Lauraceae, Theaceae, Hamamelidaceae, Magnoliaceae, Ericaceae, Styracaceae, Aquifoliaceae, Elaeocarpaceae, Aceraceae, Rosaceae, Corylaceae, Daphniphyllaceae, Symplocaceae, Euphorbiaceae, Pinaceae, Taxodiaceae, Cupressaceae and Taxaceae. Ancient and relic taxa include Ginkgo biloba, Fokieniahodginsii, Amentotaxusargotaenia, Disanthuscercidifolia subsp. longipes, Hamamelismollis, Manglietiafordiana, Magnoliaofficinalis, Tsoongiodendronodorum, Fortuneariasinensis, Cyclocaryapaliurus, Eucommiaulmoides, Sargentodoxacuneata, Bretschneiderasinensis, Camptothecaacuminata, Tapisciasinensis, etc. The flora of Mount Jinggangshan region includes 79 cosmopolitan genera and 924 non-cosmopolitan genera, which are 7.88% and 92.12% of all genera. The latter includes 452 tropical genera (48.92% and 472 temperate genera (51.08%. The temperate elements include 44 genera endemic to China, accounting for 4.76% of all genera. Among 1,003 genera, 465 have only a single species and 401 are oligotypic genera (with 2-5 species. These genera account for 86.34% of all genera. The floristic analysis indicates that the flora of Mount Jinggangshan region is closely related to the flora of Mount Wuyishan region in southeastern China. The flora of Mount Jinggangshan region also contains many elements of central and

  15. The seed plant flora of the Mount Jinggangshan region, southeastern China.

    Science.gov (United States)

    Wang, Lei; Liao, Wenbo; Chen, Chunquan; Fan, Qiang

    2013-01-01

    The Mount Jinggangshan region is located between Jiangxi and Hunan provinces in southeastern China in the central section of the Luoxiao Mountains. A detailed investigation of Mount Jinggangshan region shows that the seed plant flora comprises 2,958 species in 1,003 genera and 210 families (Engler's system adjusted according to Zhengyi Wu's concept). Among them, 23 species of gymnospermae belong to 17 genera and 9 families, and 2,935 species of angiosperms are in 986 genera and 201 families. Moreover, they can also be sorted into woody plants (350 genera and 1,295 species) and herbaceous plants (653 genera and 1,663 species). The dominant families are mainly Fagaceae, Lauraceae, Theaceae, Hamamelidaceae, Magnoliaceae, Ericaceae, Styracaceae, Aquifoliaceae, Elaeocarpaceae, Aceraceae, Rosaceae, Corylaceae, Daphniphyllaceae, Symplocaceae, Euphorbiaceae, Pinaceae, Taxodiaceae, Cupressaceae and Taxaceae. Ancient and relic taxa include Ginkgo biloba, Fokieniahodginsii, Amentotaxusargotaenia, Disanthuscercidifolia subsp. longipes, Hamamelismollis, Manglietiafordiana, Magnoliaofficinalis, Tsoongiodendronodorum, Fortuneariasinensis, Cyclocaryapaliurus, Eucommiaulmoides, Sargentodoxacuneata, Bretschneiderasinensis, Camptothecaacuminata, Tapisciasinensis, etc. The flora of Mount Jinggangshan region includes 79 cosmopolitan genera and 924 non-cosmopolitan genera, which are 7.88% and 92.12% of all genera. The latter includes 452 tropical genera (48.92%) and 472 temperate genera (51.08%). The temperate elements include 44 genera endemic to China, accounting for 4.76% of all genera. Among 1,003 genera, 465 have only a single species and 401 are oligotypic genera (with 2-5 species). These genera account for 86.34% of all genera. The floristic analysis indicates that the flora of Mount Jinggangshan region is closely related to the flora of Mount Wuyishan region in southeastern China. The flora of Mount Jinggangshan region also contains many elements of central and southern China

  16. Mountain Child: Systematic Literature Review.

    Science.gov (United States)

    Audsley, Annie; Wallace, Rebecca M M; Price, Martin F

    2016-12-01

    Objectives This systematic review identifies and reviews both peer-reviewed and 'grey' literature, across a range of disciplines and from diverse sources, relating to the condition of children living in mountain communities in low- and middle-income countries. Findings The literature on poverty in these communities does not generally focus on the particular vulnerabilities of children or the impact of intersecting vulnerabilities on the most marginalised members of communities. However, this literature does contribute analyses of the broader context and variety of factors impacting on human development in mountainous areas. The literature on other areas of children's lives-health, nutrition, child mortality, education, and child labour-focuses more specifically on children's particular vulnerabilities or experiences. However, it sometimes lacks the broader analysis of the many interrelated characteristics of a mountainous environment which impact on children's situations. Themes Nevertheless, certain themes recur across many disciplines and types of literature, and point to some general conclusions: mountain poverty is influenced by the very local specificities of the physical environment; mountain communities are often politically and economically marginalised, particularly for the most vulnerable within these communities, including children; and mountain communities themselves are an important locus for challenging and interrupting cycles of increasing inequality and disadvantage. While this broad-scale review represents a modest first step, its findings provide the basis for further investigation.

  17. Analysis of linear force open bow archery athlete%射箭运动员开弓直线力的分析

    Institute of Scientific and Technical Information of China (English)

    林志坚

    2014-01-01

    射箭运动是一项借助弓的弹力,在规定范围内,准确瞄准目标发射的一项体育锻炼项目,对射击运动员开弓直线力的要求较高。文章主要通过查阅大量有关韩国高水平射手的开弓动作技术特征,从理论上进行分析,以揭示开弓动作及具相关技术的潜在规律,旨在有效提高设计运动员的开弓质量和实际比赛水平。%With archery bow is a stretch, within the specified range, accurate targeting of a physical exercise program launch .Higher on the open bow shooters linear force requirements, the article by referring to a large number of high-level technical features of the Korean action shooter open bow, theoretically analyzed to reveal potentially open bow action and laws related technologies. Aims to improve the quality and the actual game open bow design level athletes.

  18. Glacial Ice Velocity Determination and Correlation from Different Mountain Ranges Using Aster Imagery

    Science.gov (United States)

    Pleasants, M.; Haritashya, U. K.

    2013-12-01

    Mountain glaciers make good indicators of even slight changes in climatic conditions because of their sensitivity to temperature and other environmental changes. Due to the inaccessibility of most mountain glaciers, field based measurements of glacier dynamics, especially ice velocities, has proved to be difficult and unrealistic. Because of this, evaluation of satellite imagery has become useful in the determination of glacial ice velocities and production of ice flow models. The calculation and comparison of ice velocities from three glaciated regions (the Southern Alps of New Zealand, the North-east Nepali Himalaya, and the south-eastern Chugach Mountains of Alaska) is presented here. This study was completed to establish the accuracy and global applicability of the method of precise orthorectification, co-registration, and correlation using the software COSI-Corr and in-house filtering techniques. We chose glaciers from different mountain ranges that present different dynamics to establish a specific ice velocity method. Advanced Spacebourne Thermal Emission and Reflection Radiometer (ASTER) L1A images were chosen as close to annual pairs as possible from the available data at the USGS Global Visualization Viewer (GloVis). This study focuses on the Tasman glacier in New Zealand, the Khumbu glacier in the Himalayas, the previously unstudied Scott glacier in Alaska, and the comparison of these ice velocities to climate data for each region compiled from numerous sources in an attempt to draw conclusions of the behavior of these glaciers in response to current climatic changes.

  19. Structural evidence for northeastward movement on the Chocolate Mountains thrust, southeasternmost Calfornia

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, J.T. (Alaska Div. of Geological and Geophysical Surveys, Fairbanks (USA)); Haxel, G.B. (Geological Survey, Flagstaff, AZ (USA)); Tosdal, R.M. (Geological Survey, Menlo Park, CA (USA))

    1990-11-10

    The Late Cretaceous Chocolate Mountains thrust of southeastern California and southwestern Arizona places a block of Proterozoic and Mesozoic continental crust over the late Mesozoic continental margin oceanic sedimentary and volcanic rocks of the regionally distinctive Orocopia Schist. The Chocolate Mountains thrust is interpreted as a thrust (burial, subduction) fault rather than a low-angle normal (exhumation, unroofing, uplift) fault. The Chocolate Mountains thrust zone contains sparse to locally abundant mesoscopic asymmetric folds. Fabric relations indicate that these folds are an integral part of and coeval with the thrust zone. On a lower hemisphere equal-area plot representing the orientation and sense of asymmetry of 80 thrust zone folds from 36 localities, spread over an area 60 by 10 km, Z folds plot northwest of and S folds plot southeast of a northeast-southwest striking vertical plane of overall monoclinic symmetry. The only sense of movement consistent with the collective asymmetry of the thrust zone folds is top to the northeast. Paleomagnetic data suggest that the original sense of thrusting, prior to Neogene vertical axis tectonic rotation related to the San Andreas fault system, was northward. The essential point is that movement of the upper plate of the Chocolate Mountains thrust evidently was continentward. Continentward thrusting suggests a tectonic scenario in which an insular or peninsular microcontinental fragment collided with mainland southern California. Alternative tectonic models involving subduction of the Orocopia Schist eastward beneath continental southern California circumvent the suture problem but are presently not supported by any direct structural evidence.

  20. Mesozoic denudation and cooling events of the Yinshan Mountains, southern Mongolian Plateau

    Science.gov (United States)

    Feng, Li-Xia; Han, Bao-Fu; Wang, Zeng-Zhen; Liu, Bo; Brown, Roderick

    2016-04-01

    ABASTRACT The Yinshan Mountains are south boundary of the Mongolian Plateau, occupying the north part of North China Craton. 18 granitoid samples were conducted by apatite fission track method in order to unravel its Mesozoic denudation and cooling history and relationship with the Mongolian Plateau. They obtain Jurassic to Cretaceous AFT ages. 3 main phases of rapid cooling events during Mesozoic are recognized and could probably be caused by denudation. Combined with local geological conditions, denudations are more likely controlled by the local thrust faulting. The Early Jurassic denudation event occurred in the transition area to the Mongolian Plateau. The Late Jurassic to Early Cretaceous denudation events occurred in the interior mountains and are more likely provoked by the distant effect of the Mongol-Okhotsk Orogeny based on their propagation directions. The Late Cretaceous denudation event occurred in the southeastern flank of the mountain. Finally, the activity time of thrust faults are constrained by 130-90 Ma according to the uplift and denudation relationship in the thrust system and their modeling T-t paths. Key words Apatite Fission track; Uplift and denudation; Mesozoic reactivation; Mountain Langshan

  1. Dengue Virus in Bats from Southeastern Mexico

    Science.gov (United States)

    Sotomayor-Bonilla, Jesús; Chaves, Andrea; Rico-Chávez, Oscar; Rostal, Melinda K.; Ojeda-Flores, Rafael; Salas-Rojas, Mónica; Aguilar-Setien, Álvaro; Ibáñez-Bernal, Sergio; Barbachano-Guerrero, Arturo; Gutiérrez-Espeleta, Gustavo; Aguilar-Faisal, J. Leopoldo; Aguirre, A. Alonso; Daszak, Peter; Suzán, Gerardo

    2014-01-01

    To identify the relationship between landscape use and dengue virus (DENV) occurrence in bats, we investigated the presence of DENV from anthropogenically changed and unaltered landscapes in two Biosphere Reserves: Calakmul (Campeche) and Montes Azules (Chiapas) in southern Mexico. Spleen samples of 146 bats, belonging to 16 species, were tested for four DENV serotypes with standard reverse transcriptase polymerase chain reaction (RT-PCR) protocols. Six bats (4.1%) tested positive for DENV-2: four bats in Calakmul (two Glossophaga soricina, one Artibeus jamaicensis, and one A. lituratus) and two bats in Montes Azules (both A. lituratus). No effect of anthropogenic disturbance on the occurrence of DENV was detected; however, all three RT-PCR–positive bat species are considered abundant species in the Neotropics and well-adapted to disturbed habitats. To our knowledge, this study is the first study conducted in southeastern Mexico to identify DENV-2 in bats by a widely accepted RT-PCR protocol. The role that bats play on DENV's ecology remains undetermined. PMID:24752688

  2. Significance of the 'bow and lean test' for the diagnosis of benign horizontal semicircular canal paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Ying CHEN

    2012-10-01

    Full Text Available Objective To observe and assess the positive rate and accuracy of 'bow and lean test' in the horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV. Methods Ninety-two HSC-BPPV patients who were diagnosed by head roll test (HRT were enrolled, and then further tested with 'bow and lean test' (BLT between Oct 1, 2010 and Sep 30, 2011. They were treated by Barbecue maneuver or Brandt-Daroff exercise on the basis of HRT and BLT tests. The positive rate of BLT test was analyzed, and its accuracy for diagnosis and success rate for treatment of HSC-BPPV were compared between HRT and BLT. Results Among the 92 patients, 83(90.2% of them showed BLT nystagmus. Fifty-seven of 83 (68.7% patients showed both bowing nystagmus and leaning nystagmus, and 18(21.7% and 8(9.6% respectively showed bowing nystagmus alone or leaning nystagmus alone. Among 92 patients, 74(80.4% of them the affected side could be determined by HRT with 69 BLT positive and 5 BLT negative. Among the 69 BLT-positive patients, 60 patients showed the same result of HRT, and successful result was achieved by manipulation. 9 patients showed different result between BLT and HRT, in whom manipulation failed according to the result of HRT, but succeeded when manipulation was performed according to BLT. In 18 patients(19.6% it was not able to determine the affected side by HRT, but in 14 patients manipulation was successful when BLT result was applied. In 4 patients BLT failed to evoke nystagmus, but after practicing Brandt-Daroff exercise, vertigo and HRT nystagmus disappeared 3 days later. Among the 92 patients, 65(70.7% were cured according to HRT, while 83(90.2% got successful result according to BLT(P < 0.05. Conclusion The positive rate and accuracy for HSC-BPPV by BLT are high. It is a useful method for determining the affected side in HSC-BPPV, and to provide the basis for selecting effective manipulation treatment.

  3. Direct measurement of the cross-shock electric potential at low plasma $\\beta$, quasi-perpendicular bow shocks

    OpenAIRE

    Bale, S. D.; Mozer, F.S.; Krasnoselskikh, V.V.

    2008-01-01

    We use the Cluster EFW experiment to measure the cross-shock electric field at ten low $\\beta$, quasi-perpendicular supercritical bow shock crossings on March 31, 2001. The electric field data are Lorentz-tranformed to a Normal Incidence frame (NIF), in which the incoming solar wind velocity is aligned with the shock normal. In a boundary normal coordinate system, the cross-shock (normal) electric field is integrated to obtain the cross shock potential. Using this technique, we measure the cr...

  4. Early treatment of class III malocclusion with modified tandem traction bow appliance and a brief literature review.

    Science.gov (United States)

    Sharma, Akhilesh; Joshi, Sourabh Ramesh; Hegde, Amitha M; Shetty, Rajmohan

    2014-09-01

    The accurate diagnosis and clinical management of class III malocclusion continues to be a challenging task for the pediatric dentist due to the poor compliance of patient and high rate of relapse. Two cases of early treatment of class III malocclusion are presented which were treated by modified tandem traction bow appliance. The correction in the cross bite was achieved in six to seven months. Children's compliance and acceptance for the appliance was good. Follow up of two years and one years showed no relapse.

  5. The origins of mountain geoecology

    Directory of Open Access Journals (Sweden)

    Ives, Jack D.

    2012-05-01

    Full Text Available Mountain geoecology, as a sub-discipline of Geography, stems from the life and work of Carl Troll who, in turn, was inspired by the philosophy and mountain travels of Alexander von Humboldt. As founding chair of the IGU Commission on High-Altitude Geoecology (1968, Troll laid the foundations for inter-disciplinary and international mountain research. The paper traces the evolution of the Commission and its close links with the UNESCO Man and Biosphere Programme (1972- and the United Nations University’s mountain Project (1978-. This facilitated the formation of a major force for inclusion of a mountain chapter in AGENDA 21 during the 1992 Rio de Janeiro Herat Summit (UNCED and the related designation by the United Nations of 2002 as the International Year of Mountains. In this way, mountain geoecology not only contributed to worldwide mountain research but also entered the political arena in the struggle for sustainable mountain development and the well-being of mountain people.La geoecología de montaña, como sub-disciplina de la Geografía, entronca con la vida y trabajo de Carl Troll, quien, a su vez, fue inspirado por la filosofía y viajes de Alexander von Humboldt. Como presidente fundador de la comisión de la UGI sobre High Altitude Geoecology (1968, Troll colocó las bases para la investigación interdisciplinar e internacional de las montañas. Este trabajo presenta la evolución de la Comisión y sus estrechas relaciones con el Programa Hombre y Biosfera de UNESCO (1972- y con el Proyecto de montaña de la Universidad de Naciones Unidas (1978-. Esto facilitó la inclusión de un capítulo sobre la montaña en AGENDA 21 durante la Cumbre de la Tierra de Río de Janeiro (UNCED, y la consiguiente designación de 2002 como el Año Internacional de las Montañas por parte de Naciones Unidas. En este sentido, la geoecología de montaña no sólo contribuyó a la investigación de las montañas del mundo sino que también empujó a la pol

  6. Minor-form/microform cleft lip repair: the importance of identification and utilization of Cupid bow peak on the lateral lip.

    Science.gov (United States)

    Oyama, Akihiko; Funayama, Emi; Furukawa, Hiroshi; Hayashi, Toshihiko; Saito, Akira; Yamamoto, Yuhei

    2014-01-01

    In minor-form or microform cleft lip, normal anatomical structures with slight displacement remain and should be used effectively to obtain symmetrical results. We treated 7 patients with minor-form or microform cleft lip between 2005 and 2009. In all patients, the peak of Cupid bow with a natural curve of the white roll was recognized on the lateral lip. We modified the incision line to maintain the natural curve and obtained a symmetrical and natural-looking Cupid bow. In this article, we emphasize the importance of preserving the remaining normal structure, particularly the curve of the white roll on the lateral lip, and suggest that the peak of the curve should be defined as Cupid bow peak of the cleft side. Details of our concept for the correction of minor-form or microform cleft lip are also introduced.

  7. Whole-rock Pb and Sm-Nd isotopic constraints on the growth of southeastern Laurentia during Grenvillian orogenesis

    Science.gov (United States)

    Fisher, C.M.; Loewy, S.L.; Miller, C.F.; Berquist, P.; Van Schmus, W. R.; Hatcher, R.D.; Wooden, J.L.; Fullagar, P.D.

    2010-01-01

    The conventional view that the basement of the southern and central Appalachians represents juvenile Mesoproterozoic crust, the final stage of growth of Laurentia prior to Grenville collision, has recently been challenged. New whole-rock Pb and Sm-Nd isotopic data are presented from Meso protero zoic basement in the southern and central Appalachians and the Granite-Rhyolite province, as well as one new U-Pb zircon age from the Granite-Rhyolite province. These data, combined with existing data from Mesoproterozoic terranes throughout southeastern Laurentia, further substantiate recent suggestions that the southern and central Appalachian basement is exotic with respect to Laurentia. Sm-Nd isotopic compositions of most rocks from the southern and central Appalachian basement are consistent with progressive growth through reworking of the adjacent Granite-Rhyolite province. However, Pb isotopic data, including new analyses from important regions not sampled in previous studies, do not correspond with Pb isotopic compositions of any adjacent crust. The most distinct ages and isotopic compositions in the southern and central Appalachian basement come from the Roan Mountain area, eastern Tennessee-western North Carolina. The data set indicates U-Pb zircon ages up to 1.8 Ga for igneous rocks, inherited and detrital zircon ages >2.0 Ga, Sm-Nd depleted mantle model (TDM) ages >2.0 Ga, and the most elevated 207Pb/204Pb observed in southeastern Laurentia. The combined U-Pb geochronologic and Sm-Nd and Pb isotopic data preclude derivation of southern and central Appalachian basement from any nearby crustal material and demonstrate that Grenville age crust in southeastern Laurentia is exotic and probably was transferred during collision and assembly of Rodinia. These new data better define the boundary between the exotic southern and central Appalachian basement and adjacent Laurentian Granite-Rhyolite province. ?? 2010 Geological Society of America.

  8. Large Scale Earth's Bow Shock with Northern IMF as simulated by PIC code in parallel with MHD model

    CERN Document Server

    Baraka, Suleiman M

    2016-01-01

    In this paper, we propose a 3D kinetic model (Particle-in-Cell PIC ) for the description of the large scale Earth's bow shock. The proposed version is stable and does not require huge or extensive computer resources. Because PIC simulations work with scaled plasma and field parameters, we also propose to validate our code by comparing its results with the available MHD simulations under same scaled Solar wind ( SW ) and ( IMF ) conditions. We report new results from the two models. In both codes the Earth's bow shock position is found to be ~14.8 RE along the Sun-Earth line, and ~ 29 RE on the dusk side. Those findings are consistent with past in situ observations. Both simulations reproduce the theoretical jump conditions at the shock. However, the PIC code density and temperature distributions are inflated and slightly shifted sunward when compared to the MHD results. Kinetic electron motions and reflected ions upstream may cause this sunward shift. Species distributions in the foreshock region are depicted...

  9. Risk Analysis on Leakage Failure of Natural Gas Pipelines by Fuzzy Bayesian Network with a Bow-Tie Model

    Directory of Open Access Journals (Sweden)

    Xian Shan

    2017-01-01

    Full Text Available Pipeline is the major mode of natural gas transportation. Leakage of natural gas pipelines may cause explosions and fires, resulting in casualties, environmental damage, and material loss. Efficient risk analysis is of great significance for preventing and mitigating such potential accidents. The objective of this study is to present a practical risk assessment method based on Bow-tie model and Bayesian network for risk analysis of natural gas pipeline leakage. Firstly, identify the potential risk factors and consequences of the failure. Then construct the Bow-tie model, use the quantitative analysis of Bayesian network to find the weak links in the system, and make a prediction of the control measures to reduce the rate of the accident. In order to deal with the uncertainty existing in the determination of the probability of basic events, fuzzy logic method is used. Results of a case study show that the most likely causes of natural gas pipeline leakage occurrence are parties ignore signage, implicit signage, overload, and design defect of auxiliaries. Once the leakage occurs, it is most likely to result in fire and explosion. Corresponding measures taken on time will reduce the disaster degree of accidents to the least extent.

  10. Location Estimation of the Bow Shock and Theta angle (B, n) cuasiperpendicular magnetospheric, using data from 14 different events crossings shock recorded by THEMIS-C.

    Science.gov (United States)

    Amazo-Gomez, Eliana; Alvarado-Gomez, Julian David; Calvo Mozo, Benjamin

    In this Work we calculated the average position of the bow shock, through the eigenvalues ​​and corresponding eigenvectors of the covariance matrix for the magnetic field developed from 10 different crosses shock events recorded by THEMIS A, during the years 2009 and 2010. With data obtained from previous calibration and the propagation direction of the magnetic field of the plasma is able to find the interaction quasi perpendicular angle Theta (B,n) which depends on the direction normal shock and the direction of incidence of field magnetic plasma. The importance of this type of analysis is that the understanding of the phenomenology of the bow shock, which is vital for the characterization of processes such as magnetic reconnection between magnetospheric lines terrestrial and interplanetary field lines carrying a large contribution from the Sun apparently lines will also be important for the description of how to enter the plasma charged particles from impacting the bow shock to the internal field lines to these particles subsequently lead to the Earth's atmosphere, these initially enter through the polar region (Polar Cusp) and then disseminated depending on the conditions of the plasma into the Earth's atmosphere , and parameters such as the position of the bow shock, this variation and interaction angle Theta (B,n) are basic to reach a minimal representation of the phenomenon. In events of great magnitude can have undesirable effects on satellites, power lines, communications and air travel, the latter is the interest on discrimination of some parameters of the phenomenon presented in this work. The study of the Bow shock, bow shock and Magnetospheric has as its starting point a detailed description of Earth's magnetosphere and solar wind phenomena must be understood independently initially and then trying to relate in terms of their interaction and communion in their respective limits, parameters such as the balance between dynamic and magnetic pressure

  11. Phylogeography of the large white-bellied rat Niviventer excelsior suggests the influence of Pleistocene glaciations in the Hengduan mountains.

    Science.gov (United States)

    Chen, Weicai; Liu, Shaoying; Liu, Yang; Hao, Haibang; Zeng, Bo; Chen, Shunde; Peng, Hongyuan; Yue, Bisong; Zhang, Xiuyue

    2010-06-01

    The Hengduan Mountains, situated in the southeastern Tibetan Plateau, have undergone dramatic geological and climatic changes over the Pleistocene epoch. Several studies have revealed that the mountains served as a refugium during the ice age. The large white-bellied rat Niviventer excelsior is a rodent endemic to the Hengduan Mountains, which makes it an appropriate species for investigating the influence of glacial movements on the genetic structure of mammals. In this study, we sequenced the partial mitochondrial DNA control region from 72 N. excelsior specimens collected from 20 localities. The results revealed very high levels of haplotype diversity (h = 0.947) and nucleotide diversity (pi = 0.101) in this species. No common haplotype was found to be shared in samples from all geographic regions. Demographic analyses suggested that N. excelsior populations had not been subject to either expansion or bottleneck. The phylogenetic relationships among the haplotypes have no correlation with their geographical origins, while topology revealed two major clades. We speculate that the populations of N. excelsior may have been restricted to two separate refugia during the Last Glacial Maximum (0.60-0.17 Mya), with one west and one east of the Shaluli Mountains. Between the two major refugia, there existed a more widely distributed network subrefugia, which conserved genetic variations in N. excelsior. These results indicated that complex topographic configuration in the Hengduan Mountains provided a network of refugia to maintain the high level of genetic diversity in Pleistocene glaciations.

  12. A Precipitation Climatology of the Snowy Mountains, Australia

    Science.gov (United States)

    Theobald, Alison; McGowan, Hamish; Speirs, Johanna

    2014-05-01

    The precipitation that falls in the Snowy Mountains region of southeastern Australia provides critical water resources for hydroelectric power generation. Water storages in this region are also a major source of agricultural irrigation, environmental flows, and offer a degree of flood protection for some of the major river systems in Australia. Despite this importance, there remains a knowledge gap regarding the long-term, historic variability of the synoptic weather systems that deliver precipitation to the region. This research aims to increase the understanding of long-term variations in precipitation-bearing weather systems resulting in runoff into the Snowy Mountains catchments and reservoirs, and the way in which these are influenced by large-scale climate drivers. Here we present initial results on the development of a climatology of precipitation-bearing synoptic weather systems (synoptic typology), spanning a period of over 100 years. The synoptic typology is developed from the numerical weather model re-analysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF), in conjunction with regional precipitation and temperature data from a network of private gauges. Given the importance of surface, mid- and upper-air patterns on seasonal precipitation, the synoptic typing will be based on a range of meteorological variables throughout the depth of the troposphere, highlighting the importance of different atmospheric levels on the development and steering of synoptic precipitation bearing systems. The temporal and spatial variability of these synoptic systems, their response to teleconnection forcings and their contribution to inflow generation in the headwater catchments of the Snowy Mountains will be investigated. The resulting climatology will provide new understanding of the drivers of regional-scale precipitation variability at inter- and intra-annual timescales. It will enable greater understanding of how variability in synoptic scale

  13. Rapid Oligocene Exhumation of the Western Canadian Rocky Mountains

    Science.gov (United States)

    Szameitat, A.; Parrish, R. R.; Stuart, F. M.; Carter, A.; Fishwick, S.

    2014-12-01

    As part of the North American Cordillera the Rocky Mountains of Canada impact the deflection of weather systems and the jet stream and form a distinct barrier to Pacific moisture reaching the continental interior. The extent to which this climatic pattern extended into the past is at present uncertain, so improving our understanding of the elevation history of the Rockies is critical to determining the controls on climate change within the Northern Hemisphere. We have undertaken a comprehensive apatite (U-Th-Sm)/He and fission track study of the southeastern Canadian Cordillera, i.e. the southern Canadian Rocky Mountains, in order to provide insight into the mid to late Cenozoic uplift and exhumation history of this region. Thermal history and exhumation models of widespread low elevation samples in combination with 6 vertical profiles covering elevations from 500 up to 3100 m a.s.l. show at least 1500 m of rapid exhumation west of the Rocky Mountain Trench (RMT) during the Oligocene (Figure 1). In contrast, the ranges east of the RMT low elevation samples provide Eocene ages throughout. The data show a very different history of recent uplift of the Canadian Rockies compared to what is currently known from published work, which mostly infer that the eastern Canadian Cordillera has not experienced significant uplift since the Eocene. We propose that the most likely cause of this rock uplift was upwelling of asthenosphere around the eastward subducting Farallon Plate. This also led to the eruption of the nearby mainly Miocene Chilcotin Group flood basalts and could have caused underplating of the thin lithosphere west of the RMT, adding to the buoyancy of the plate and lifting the range. Because the Trench marks the edge of the normal thickness craton which was underthrust beneath the Rocky Mountains during the initial upper Cretaceous orogeny, the eastern Rockies have a normal lithosperic thickness. This would impede recent uplift and provides an explanation for the

  14. WHITE MOUNTAIN WILDERNESS, NEW MEXICO.

    Science.gov (United States)

    Segerstrom, Kenneth; Stotelmeyer, R.B.

    1984-01-01

    On the basis of a mineral survey the White Mountain Wilderness, which constitutes much of the western and northern White Mountains, New Mexico, is appraised to have six areas of probable mineral potential for base and precious metals. If mineral deposits exist in the wilderness, the potential is for small deposits of base and precious metals in veins and breccia pipes or, more significanlty, the possibility for large low-grade disseminated porphyry-type molybdenum deposits. There is little promise for the occurrence of geothermal energy resources in the area.

  15. Yearly report, Yucca Mountain project

    Energy Technology Data Exchange (ETDEWEB)

    Brune, J.N.

    1992-09-30

    We proposed to (1) Develop our data logging and analysis equipment and techniques for analyzing seismic data from the Southern Great Basin Seismic Network (SGBSN), (2) Investigate the SGBSN data for evidence of seismicity patterns, depth distribution patterns, and correlations with geologic features (3) Repair and maintain our three broad band downhole digital seismograph stations at Nelson, nevada, Troy Canyon, Nevada, and Deep Springs, California (4) Install, operate, and log data from a super sensitive microearthquake array at Yucca Mountain (5) Analyze data from micro-earthquakes relative to seismic hazard at Yucca Mountain.

  16. Life in the Taihang Mountains

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    THE Taihang Mountain Range meanders for 500 kilometers across the territories of Henan, Shanxi and Hebei provinces. It is an important ecological screen for the North China Plain and source of water. In Hebei’s Shexian County sits Wangjinzhuang, a 300-year-old stone village nestled in the mountains.The village is a stone world-lanes, houses, court-yard walls, towers, pavilions, tables, benches and mills are all hewn fom ancient rock. Streets and lanes are paved in stones of various shapes and sizes whose sur-

  17. Groundwater quality in the Southeastern Coastal Plain aquifer system, southeastern United States

    Science.gov (United States)

    Barlow, Jeannie; Lindsey, Bruce; Belitz, Kenneth

    2017-01-19

    Groundwater provides nearly 50 percent of the Nation’s drinking water. To help protect this vital resource, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water. The Southeastern Coastal Plain aquifer system constitutes one of the important areas being evaluated. One or more inorganic constituents with human-health benchmarks were detected at high concentrations in about 6 percent of the study area and at moderate concentrations in about 13 percent. One or more organic constituents with human-health benchmarks were detected at moderate concentrations in about 3 percent of the study area.

  18. Job performance in the mountain metros

    OpenAIRE

    Mark C. Snead; Kate Watkins

    2012-01-01

    This issue of the Rocky Mountain Economist explores the labor market performance of the mountain state metropolitan areas, including recent industry trends and comparisons to state and national job performance.

  19. Rocky Mountain Spotted Fever: Statistics and Epidemiology

    Science.gov (United States)

    ... The CDC Cancel Submit Search The CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or ... please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Symptoms, Diagnosis, and Treatment Statistics ...

  20. Cheyenne Mountain Air Force Station NPDES Permit

    Science.gov (United States)

    Under NPDES permit CO-0034762, the Cheyenne Mountain Air Force Station is authorized to discharge from the interior storm drainage system and air exhaust stacks at the Cheyenne Mountain Complex, in El Paso County, Colorado, to tributaries Fountain Creek.

  1. Chinese tallow: Invading the southeastern Coastal Plain

    Science.gov (United States)

    ,

    2000-01-01

    Chinese tallow is an ornamental tree with colorful autumn foliage that can survive full sunlight and shade, flooding, drought, and in some cases fire. To horticulturists this kind of tree sounds like a dream, but to ecologists, land managers, and land owners this kind of tree can be a nightmare, especially when it invades an area and takes over native vegetation. Chinese tallow (Triadica sebifera), a nonnative tree from China, is currently transforming the southeastern Coastal Plain.Over the last 30 years, Chinese tallow has become a common tree in old fields and bottomland swamps of coastal Louisiana. Several studies at the U.S. Geological Survey’s National Wetlands Research Center (NWRC), Lafayette, Louisiana, are aimed at understanding the factors that contribute to Chinese tallow growth, spread, and management.When tallow invades, it eventually monopolizes an area, creating a forest without native animal or plant species. This tree exhibits classic traits of most nonnative invaders: it is attractive so people want to distribute it, it has incredible resiliency, it grows quickly and in a variety of soils, and it is resistant to pests.In the coastal prairie of Louisiana and Texas, Chinese tallow can grow up to 30 feet and shade out native sun-loving prairie species. The disappearing of prairie species is troublesome because less than 1% of original coastal prairie remains, and in Louisiana, less than 500 of the original 2.2 million acres still exist.Tallow reproduces and grows quickly and can cause large-scale ecosystem modification (fig. 1). For example, when it completely replaces native vegetation, it has a negative effect on birds by degrading the habitat. Besides shading out grasses that cattle like to eat, it can also be potentially harmful to humans and animals because of its berries (fig. 2) and plant sap that contain toxins. There is some concern its leaves may shed toxins that change the soil chemistry and make it difficult for other plants to grow.

  2. Tectonic history of the southeastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Hatcher, R.D. Jr. (Univ. of Tennessee, Knoxville, TN (United States). Dept. of Geological Sciences Oak Ridge National Lab., TN (United States))

    1993-03-01

    The present-day configuration of the crust of southeastern North America (SENA) is the product of a lengthy history traceable through more than 1 billion yr. of geologic time. The Appalachians (AP) record complete Wilson cycles of opening and closing of several oceans from ca. 690 Ma to 245 M. The final event forming the AP was the collision of SENA with Gondwana to form the supercontinent Pangaea. The Ouachitas (OA) had a somewhat different history culminating with island-arc collision during the Pennsylvanian--before the final collision began in the AP. SENA faced the open lapetos ocean no earlier than the Early Cambrian. The AP and OA were built on an earlier margin formed by rifting of the Rodonia super-continent formed by construction of the 1.2 to 1.0 Ga Grenville orogen, and farther west, a crust formed by still earlier (1.3 and 1.8 Ga) events. Recent suggestions that part of the AP platform is in Argentina raises the possibility that a fragment was rifted from between the AP and OA during the early Paleozoic. The crust beneath the Mississippi Embayment is atypical of continental crust, and would have been rifted during the Neoproterozoic and early Paleozoic. The Argentine fragment may have been removed along a transform that was reactivated several times since. Northern Pangaea was rifted during the Late Triassic and Early Jurassic and SENA once again faced open ocean-the nascent present Atlantic (AT) when spreading began. The Gulf of Mexico (GOM) also opened then forming extensive salt deposits. The AT opened partly along the old suture, but produced a failed rift in GA and FL leaving a piece of Africa forming the crust beneath the Coastal Plain as far south as central FL. The overlying sediments record recurrent uplift and decay of the AP and OA, cooling of new AT oceanic crust, eustatic sea-level changes during the Mesozoic and Cenozoic, and uplift of the Rockies providing a new source of voluminous detritus that is still being deposited in the GOM.

  3. Bat assemblages from three Atlantic Forest fragments in Rio de Janeiro state, Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Roberto Leonan Novaes

    2015-01-01

    Full Text Available Bat species richness in Neotropical localities is generally higher than that of any other group of mammals, and surveys of local bat assemblages may provide useful data for conservation management plans. Although the bat fauna of the Rio de Janeiro state is currently one of the best known in Brazil, there are several localities not adequately surveyed yet, and most of them are in the mountainous regions and in the northern portion of the state. From January 2008 to November 2009, we conducted surveys of bats in three localities in the state of Rio de Janeiro (municipalities of Varre-Sai, Sumidouro, and Cantagalo, and our fieldwork constitutes the first assessment of the bat assemblages of these localities. Surveys were conducted using mist nets in four different habitat types in each locality (forest interior, forest edge, riparian forest, and open areas [pastures]. We captured a total of 148 individuals in 17 species, 14 genera and 3 families. Among them, 11 species were recorded in Sumidouro, seven in Cantagalo, and nine in Varre-Sai. Although species richness was low compared with previous surveys in other close localities, we recorded species that have been rarely sampled in Southeastern Brazil (e.g., Macrophyllum macrophyllum [Phyllostomidae]. The results reinforce the importance of sampling different habitats in short surveys to improve the number of species registered.

  4. Rock glaciers, protalus ramparts and pronival ramparts in the south-eastern Alps

    Science.gov (United States)

    Colucci, R. R.; Boccali, C.; Žebre, M.; Guglielmin, M.

    2016-09-01

    Rock glaciers and protalus ramparts are characteristic landforms of the periglacial domain often used as markers for the occurrence of permafrost in mountain terrains. As such, relict rock glaciers can be used for paleoclimate reconstructions. We present here the first previously unreported rock glacier inventory of the south-eastern Alps (including the north-eastern-most region of Italy and Slovenia), interpreted from high resolution orthophotos and a high resolution digital terrain model interpolated from airborne laser scanning (LiDAR). We mapped 53 rock glaciers covering a total area of 3.45 km2. The majority of rock glaciers are classified as relict and distributed between 1708 and 1846 m a.s.l. with slope ranging between 19° and 27°. In addition to rock glaciers we observed 66 protalus (pronival) ramparts, having median elevation of 1913 m a.s.l. and covering 0.48 km2. More than half of the inventoried protalus ramparts are located in the more maritime area of the Alps with higher precipitation compared to the location of rock glaciers. Using paleoclimate reconstruction based on the 1981-2010 climatological record of the area, we infer that the rock glaciers formed during one of the dry and cold periods of the late Pleistocene and early Holocene. Possible evolution of the active pronival forms observed in the most maritime area of this alpine sector is also discussed.

  5. The foreign investments phenomena in south-eastern European countries

    Directory of Open Access Journals (Sweden)

    Teodora ALECU

    2010-01-01

    Full Text Available The south-eastern Europe countries have all the common history of the communism policy and economy, which from the foreign investments perspective meant a radical approach, which promoted a nationalism view against foreign capital interference. Similar to China, perhaps India and other countries, the governments of the south-eastern Europe’s countries expressed a rejection to foreign investments, emphasizing the negative effects of such operations, arguing that any foreign capital inflow is followed by a foreign capital outflow which at the end will destabilize the balance of external payments and will overall result in no favorable effect upon the economy of their countries.

  6. Extending GIS Technology to Study Karst Features of Southeastern Minnesota

    Science.gov (United States)

    Gao, Y.; Tipping, R. G.; Alexander, E. C.; Alexander, S. C.

    2001-12-01

    This paper summarizes ongoing research on karst feature distribution of southeastern Minnesota. The main goals of this interdisciplinary research are: 1) to look for large-scale patterns in the rate and distribution of sinkhole development; 2) to conduct statistical tests of hypotheses about the formation of sinkholes; 3) to create management tools for land-use managers and planners; and 4) to deliver geomorphic and hydrogeologic criteria for making scientifically valid land-use policies and ethical decisions in karst areas of southeastern Minnesota. Existing county and sub-county karst feature datasets of southeastern Minnesota have been assembled into a large GIS-based database capable of analyzing the entire data set. The central database management system (DBMS) is a relational GIS-based system interacting with three modules: GIS, statistical and hydrogeologic modules. ArcInfo and ArcView were used to generate a series of 2D and 3D maps depicting karst feature distributions in southeastern Minnesota. IRIS ExplorerTM was used to produce satisfying 3D maps and animations using data exported from GIS-based database. Nearest-neighbor analysis has been used to test sinkhole distributions in different topographic and geologic settings. All current nearest-neighbor analyses testify that sinkholes in southeastern Minnesota are not evenly distributed in this area (i.e., they tend to be clustered). More detailed statistical methods such as cluster analysis, histograms, probability estimation, correlation and regression have been used to study the spatial distributions of some mapped karst features of southeastern Minnesota. A sinkhole probability map for Goodhue County has been constructed based on sinkhole distribution, bedrock geology, depth to bedrock, GIS buffer analysis and nearest-neighbor analysis. A series of karst features for Winona County including sinkholes, springs, seeps, stream sinks and outcrop has been mapped and entered into the Karst Feature Database

  7. Rocky Mountain Spotted Fever (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Rocky Mountain Spotted Fever KidsHealth > For Parents > Rocky Mountain Spotted Fever Print A A A What's in ... en español La rickettsiosis maculosa About RMSF Rocky Mountain spotted fever (RMSF) is a bacterial infection that's ...

  8. 49 CFR 71.8 - Mountain zone.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  9. 27 CFR 9.94 - Howell Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Howell Mountain. 9.94... Howell Mountain. (a) Name. The name of the viticultural area described in this section is “Howell Mountain.” (b) Approved maps. The appropriate maps for determining the boundaries of the Howell...

  10. Storymakers: Hopa Mountain's Early Literacy Program

    Science.gov (United States)

    Templin, Patricia A.

    2013-01-01

    Hopa Mountain's StoryMakers program is an innovative, research-based program for donating high quality young children's books to parents. Hopa Mountain is a nonprofit organization based in Bozeman, Montana. Hopa Mountain works with groups of rural and tribal citizen leaders who form StoryMakers Community Teams to talk one-on-one with local parents…

  11. 27 CFR 9.102 - Sonoma Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Sonoma Mountain. 9.102... Sonoma Mountain. (a) Name. The name of the viticultural area described in this section is “Sonoma Mountain.” (b) Approved maps. The approved maps for determining the boundary of the Sonoma...

  12. 27 CFR 9.112 - Arkansas Mountain.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Arkansas Mountain. 9.112... Arkansas Mountain. (a) Name. The name of the viticultural area described in this section is “Arkansas Mountain.” (b) Approved maps. The appropriate maps for determining the boundary of the Arkansas...

  13. Cenozoic crustal extension in southeastern Arizona and implications for models of core-complex development

    Science.gov (United States)

    Arca, M. Serkan; Kapp, Paul; Johnson, Roy A.

    2010-06-01

    In conventional models of Cordilleran-style metamorphic core-complex development, initial extension occurs along a breakaway fault, which subsequently is deformed into a synform and abandoned in response to isostatic rebound and new faults breaking forward in the dominant transport direction. The Catalina core complex and associated geology in southeastern Arizona have been pointed to as a type example of this model. From southwest to northeast, the region is characterized by the NW-SE trending Tucson basin, the Catalina core complex, the San Pedro trough and the Galiuro Mountains. The Catalina core complex is bounded by the top-to-the-southwest Catalina detachment fault along its southwestern flank and the low-angle, northeast-dipping San Pedro fault along its northeastern flank. The Galiuro Mountains expose non-mylonitic rocks and are separated from the San Pedro trough to the southwest by a system of low- to moderate-angle southwest-dipping normal faults. This Galiuro fault system is widely interpreted to be the breakaway zone for the Catalina core complex. It is inferred to be folded into a synform beneath the San Pedro trough, to resurface to the southwest as the San Pedro fault, and to have been abandoned during slip along the younger Catalina detachment. This study aimed to test this model through analysis of field relations and geochronological age constraints, and reprocessing and interpretation of 2-D seismic reflection data from the Catalina core complex and San Pedro trough. In contrast to predictions of the conventional breakaway zone model, we raise the possibility of a moderate-angle, southwest-dipping detachment fault beneath the San Pedro trough that could extend to mid-crustal depths beneath the eastern flank of the Catalina Mountains. We present an alternative kinematic model in which extension was accommodated by a pair of top-to-the-southwest normal-fault systems (the Catalina and Galiuro detachment faults), with the only major difference

  14. Years Spent on Mountain Roads

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    SONG Fangrong, the Tu nationality girl who grew up drinking water from mountain springs, walked into the Great Hall of the People in Beijing to accept the highest prize for China’s youth—the "May 4th Youth Prize." Not long before, she had been named one of the National Ten Outstanding Youths. She is the only individual to have won both.

  15. A mountain of millipedes V

    DEFF Research Database (Denmark)

    Enghoff, Henrik

    2016-01-01

    Three new genera of Odontopygidae are described, all based on new species from the Udzungwa mountains, Tanzania, and all monotypic: Casuariverpa gen. nov. (type species: C. scarpa gen. et sp. nov.), Yia gen. nov. (type species: Y. geminispina gen. et sp. nov.), and Utiliverpa gen. nov. (type...

  16. A mountain of millipedes III

    DEFF Research Database (Denmark)

    Enghoff, Henrik

    2016-01-01

    The new genus Geotypodon gen. nov. is described. It includes two species from the Udzungwa Mountains: G. millemanus gen. et sp. nov. (type species) and G. submontanus gen. et sp. nov., one species from nearby Iringa: G. iringensis gen. et sp. nov., and 18 previously described species hitherto...

  17. A mountain of millipedes I

    DEFF Research Database (Denmark)

    Enghoff, Henrik

    2014-01-01

    Twenty new species of the millipede genus Chaleponcus Attems, 1914, are described from the Udzungwa Mountains: C. netus sp. nov., C. quasimodo sp. nov., C. malleolus sp. nov., C. scopus sp. nov., C. nikolajscharffi sp. nov., C. mwanihanensis sp. nov., C. basiliscus sp. nov., C. krai sp. nov., C...

  18. End-Fire Phased Array 5G Antenna Design Using Leaf-Shaped Bow-Tie Elements for 28/38 GHz MIMO Applications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert F.

    2016-01-01

    In this paper, a new design of mm-Wave phased array 5G antenna for multiple-input multiple-output (MIMO) applications has been introduced. Two identical linear phased arrays with eight leaf-shaped bow-tie antenna elements have been used at different sides of the mobile-phone PCB. An Arlon AR 350...

  19. AE AURIGAE: FIRST DETECTION OF NON-THERMAL X-RAY EMISSION FROM A BOW SHOCK PRODUCED BY A RUNAWAY STAR

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Santiago, J.; Pereira, V.; De Castro, E. [Dpto. de Astrofisica y CC. de la Atmosfera, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Miceli, M.; Bonito, R. [Dipartimento di Fisica, Universita di Palermo, Piazza del Parlamento 1, I-90134 Palermo (Italy); Del Valle, M. V.; Romero, G. E. [Instituto Argentino de Radioastronomia (IAR), CCT La Plata (CONICET), C.C.5, 1894 Villa Elisa, Buenos Aires (Argentina); Albacete-Colombo, J. F. [Centro Universitario Regional Zona Atlantica (CURZA), Universidad Nacional del COMAHUE, Monsenor Esandi y Ayacucho, 8500 Viedma, Rio Negro (Argentina); Damiani, F. [INAF-Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, I-90134 Palermo (Italy)

    2012-09-20

    Runaway stars produce shocks when passing through interstellar medium at supersonic velocities. Bow shocks have been detected in the mid-infrared for several high-mass runaway stars and in radio waves for one star. Theoretical models predict the production of high-energy photons by non-thermal radiative processes in a number sufficiently large to be detected in X-rays. To date, no stellar bow shock has been detected at such energies. We present the first detection of X-ray emission from a bow shock produced by a runaway star. The star is AE Aur, which was likely expelled from its birthplace due to the encounter of two massive binary systems and now is passing through the dense nebula IC 405. The X-ray emission from the bow shock is detected at 30'' northeast of the star, coinciding with an enhancement in the density of the nebula. From the analysis of the observed X-ray spectrum of the source and our theoretical emission model, we confirm that the X-ray emission is produced mainly by inverse Compton upscattering of infrared photons from dust in the shock front.

  20. Laser resonators with several mirrors and lenses with the bow-tie laser resonator with compensation for astigmatism and thermal lens enects as an example

    DEFF Research Database (Denmark)

    Abitan, Haim; Skettrup, Torben

    2005-01-01

    Laser resonators with several mirrors (lenses) have been investigated in a systematic fashion. They have been grouped into classes according to their number n of mirrors/lenses. Stability polynomials, beam waist radii and locations have been obtained for each group up to n = 4. The bow-tie laser...

  1. Crustal seismic anisotropy in southeastern Capital area, China

    Institute of Scientific and Technical Information of China (English)

    WU Jing; GAO Yuan; CHEN Yun-tai

    2008-01-01

    Shear-wave splitting parameters of 24 stations in southeastern Capital area of North China (38.5°N-39.85°N,115.5°E~118.5°E) are obtained with systematic analysis method of shear-wave splitting (SAM) based on the data recorded by Capital Area Seismograph Network (CASN) from 2002 to 2005. The results show that the average polarization of fast shear-wave in southeastern Capital area is consistent with regional maximum horizontal principal compressive stress in the area, and is also consistent with maximum horizontal principal compressive strain from GPS in North China. The average shear-wave splitting in southeastern Capital area (in basin) is different from that in northwestern Capital area where uplifts and basin exist, which means that tectonics can be related to shear-wave splitting results. Research also shows that the distribution of faults around stations can obviously affect the shear-wave splitting results, and complicated distribution of faults can result in much more scatter of shear-wave splitting. Moreover, in the north and south of the studied area (southeastern Capital area), the polarizations of fast shear-wave are not very consistent, which may be related to differences in tectonic and stress for the two areas.

  2. Rabies in the insectivorous bat Tadarida brasiliensis in Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Uieda Wilson

    1998-01-01

    Full Text Available This is the first recorded case of rabies in the insectivorous bat Tadarida brasiliensis in the State of S. Paulo, Southeastern Brazil. The infected bat was found in the afternoon while hanging on the internal wall of an urban building. This observation reinforces the notion as to the caution one must exercise regarding bats found in unusual situations.

  3. Economics of conservation systems research in the Southeastern United States

    Science.gov (United States)

    The use of conservation systems in crop production is not a new concept in the southeastern United States. In 1978, researchers from across the Southeast met in Griffin, Georgia for the first annual Southern Conservation Agricultural Systems Conference. Four of the ten presentations specifically men...

  4. Feasibility of a seismic gap in southeastern Sicily

    Energy Technology Data Exchange (ETDEWEB)

    Mulargia, F.; Baldi, P.; Achilli, V.; Broccio, F.

    1985-01-16

    A major seismic gap has been recently suggested for southeastern Sicily. The present note analyses the feasibility of such a gap on the basis of the available historic seismicity data and in light of the results of a levelling campaign which was specially designed for this purpose.

  5. Geodynamics of southeastern Tibet from seismic anisotropy and geodesy

    NARCIS (Netherlands)

    Sol, S; Meltzer, A.; Burgmann, R.; Hilst, R.D. van der; King, R.; Chen, Z.; Koons, P.; Lev, E.; Liu, Y.P.; Zeitler, P.K.; Zhang, X.; Zhang, J.; Zurek, B.

    2007-01-01

    Ongoing plate convergence between India and Eurasia provides a natural laboratory for studying the dynamics of continental collision, a first-order process in the evolution of continents, regional climate, and natural hazards. In southeastern Tibet, the fast directions of seismic anisotropy determin

  6. Marine neustonic microplastics around the southeastern coast of Korea.

    Science.gov (United States)

    Kang, Jung-Hoon; Kwon, Oh Youn; Lee, Kyun-Woo; Song, Young Kyoung; Shim, Won Joon

    2015-07-15

    We investigated floating debris around the mouth of the Nakdong River in the Southeastern Sea of Korea using a Manta trawl (330-μm mesh) and hand-net (50 μm) before (May) and after (July) the rainy season in 2012. Microplastic (microplastics (microplastics (50-330 μm) when trawl used.

  7. Medieval Tract «Arab Archery» About the Parameters of Bows and Arrows as A Historical Source

    Directory of Open Access Journals (Sweden)

    Aleksei V. Korobeinikov

    2015-06-01

    Full Text Available The article deals with the excerpts from the tract «Arab Archery» dedicated to the parameters of the arab bows and arrows. The attention is paid to the system of archers`gestures, ballistic parameters. The work has comments. The author came to the conclusion that among the archers, in all probability, there was a specialization: skillful direction (snipers by the light arrows at high speed and a high degree of sharpening lethal hit the particularly important individual goals – armored commanders, signalers, communications, monitors, and so on. While the bulk of shooters cloud of arrows showered group goals: bezdospeshnuyu (or "lightly armored" infantry, and not caring about the accuracy of each of his shots.

  8. Acceleration of solar wind ions to 1 MeV by electromagnetic structures upstream of the Earth's bow shock

    CERN Document Server

    Stasiewicz, K; Eliasson, B; Strumik, M; Yamauchi, M

    2013-01-01

    We present measurements from the ESA/NASA Cluster mission that show in situ acceleration of ions to energies of 1 MeV outside the bow shock. The observed heating can be associated with the presence of electromagnetic structures with strong spatial gradients of the electric field that lead to ion gyro-phase breaking and to the onset of chaos in ion trajectories. It results in rapid, stochastic acceleration of ions in the direction perpendicular to the ambient magnetic field. The electric potential of the structures can be compared to a field of moguls on a ski slope, capable of accelerating and ejecting the fast running skiers out of piste. This mechanism may represent the universal mechanism for perpendicular acceleration and heating of ions in the magnetosphere, the solar corona and in astrophysical plasmas. This is also a basic mechanism that can limit steepening of nonlinear electromagnetic structures at shocks and foreshocks in collisionless plasmas.

  9. Evidence for a dynamically refracted primary bow in weakly bound $^9$Be rainbow scattering from $^{16}$O

    CERN Document Server

    Ohkubo, S

    2016-01-01

    We present for the first time evidence for the existence of a dynamically refracted primary bow for $^{9}$Be+$^{16}$O scattering. This is demonstrated through the use of coupled channel calculations with an extended double folding potential derived from the density-dependent effective two-body force and precise microscopic cluster wave functions for $^{9}$Be. The calculations reproduce the experimental Airy structure in $^{9}$Be+$^{16}$O scattering well.It is found that coupling of a weakly bound $^{9}$Be nucleus to excited states plays the role of a booster lens, dynamically enhancing the refraction over the {\\it static} refraction due to the Luneburg lens mean field potential between the ground states of $^{9}$Be and $^{16}$O.

  10. Summary and evaluation of existing geological and geophysical data near prospective surface facilities in Midway Valley, Yucca Mountain Project, Nye County, Nevada; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, J.D. [Sandia National Labs., Albuquerque, NM (United States); Swan, F.H.; Wesling, J.R.; Bullard, T.F.; Perman, R.C.; Angell, M.M.; DiSilvestro, L.A. [Geomatrix Consultants, Inc., San Francisco, CA (United States)

    1992-01-01

    Midway Valley, located at the eastern base of the Yucca Mountain in southwestern Nevada, is the preferred location of the surface facilities for the potential high-level nuclear waste repository at Yucca Mountain. One goal in siting these surface facilities is to avoid faults that could produce relative displacements in excess of 5 cm in the foundations of the waste-handling buildings. This study reviews existing geologic and geophysical data that can be used to assess the potential for surface fault rupture within Midway Valley. Dominant tectonic features in Midway Valley are north-trending, westward-dipping normal faults along the margins of the valley: the Bow Ridge fault to the west and the Paintbrush Canyon fault to the east. Published estimates of average Quaternary slip rates for these faults are very low but the age of most recent displacement and the amount of displacement per event are largely unknown. Surface mapping and interpretive cross sections, based on limited drillhole and geophysical data, suggest that additional normal faults, including the postulated Midway Valley fault, may exist beneath the Quaternary/Tertiary fill within the valley. Existing data, however, are inadequate to determine the location, recency, and geometry of this faulting. To confidently assess the potential for significant Quaternary faulting in Midway Valley, additional data are needed that define the stratigraphy and structure of the strata beneath the valley, characterize the Quaternary soils and surfaces, and establish the age of faulting. The use of new and improved geophysical techniques, combined with a drilling program, offers the greatest potential for resolving subsurface structure in the valley. Mapping of surficial geologic units and logging of soil pits and trenches within these units must be completed, using accepted state-of-the-art practices supported by multiple quantitative numerical and relative age-dating techniques.

  11. Influence of atomic kinetics in the simulation of plasma microscopic properties and thermal instabilities for radiative bow shock experiments

    Science.gov (United States)

    Espinosa, G.; Rodríguez, R.; Gil, J. M.; Suzuki-Vidal, F.; Lebedev, S. V.; Ciardi, A.; Rubiano, J. G.; Martel, P.

    2017-03-01

    Numerical simulations of laboratory astrophysics experiments on plasma flows require plasma microscopic properties that are obtained by means of an atomic kinetic model. This fact implies a careful choice of the most suitable model for the experiment under analysis. Otherwise, the calculations could lead to inaccurate results and inappropriate conclusions. First, a study of the validity of the local thermodynamic equilibrium in the calculation of the average ionization, mean radiative properties, and cooling times of argon plasmas in a range of plasma conditions of interest in laboratory astrophysics experiments on radiative shocks is performed in this work. In the second part, we have made an analysis of the influence of the atomic kinetic model used to calculate plasma microscopic properties of experiments carried out on magpie on radiative bow shocks propagating in argon. The models considered were developed assuming both local and nonlocal thermodynamic equilibrium and, for the latter situation, we have considered in the kinetic model different effects such as external radiation field and plasma mixture. The microscopic properties studied were the average ionization, the charge state distributions, the monochromatic opacities and emissivities, the Planck mean opacity, and the radiative power loss. The microscopic study was made as a postprocess of a radiative-hydrodynamic simulation of the experiment. We have also performed a theoretical analysis of the influence of these atomic kinetic models in the criteria for the onset possibility of thermal instabilities due to radiative cooling in those experiments in which small structures were experimentally observed in the bow shock that could be due to this kind of instability.

  12. Large Scale Earth’s Bow Shock with Northern IMF as Simulated by PIC Code in Parallel with MHD Model

    Indian Academy of Sciences (India)

    Suleiman Baraka

    2016-06-01

    In this paper, we propose a 3D kinetic model (particle-in-cell, PIC) for the description of the large scale Earth’s bow shock. The proposed version is stable and does not require huge or extensive computer resources. Because PIC simulations work with scaled plasma and field parameters, we also propose to validate our code by comparing its results with the available MHD simulations under same scaled solar wind (SW) and (IMF) conditions. We report new results from the two models. In both codes the Earth’s bow shock position is found to be $\\approx 14.8 R_{{\\rm E}}$ along the Sun–Earth line, and $\\approx 29 R_{{\\rm E}}$ on the dusk side. Those findings are consistent with past in situ observations. Both simulations reproduce the theoretical jump conditions at the shock. However, the PIC code density and temperature distributions are inflated and slightly shifted sunward when compared to the MHD results. Kinetic electron motions and reflected ions upstream may cause this sunward shift. Species distributions in the foreshock region are depicted within the transition of the shock (measured $\\approx$2$c/\\omega_{pi}$ for $ \\Theta_{Bn}=90^{\\circ}$ and $M_{{\\rm MS}} = 4.7 $) and in the downstream. The size of the foot jump in the magnetic field at the shock is measured to be ($1.7 c/ \\omega_{pi} $). In the foreshocked region, the thermal velocity is found equal to 213 km $s^{−1}$ at $15R_{{\\rm E}}$ and is equal to $63 km s^{-1}$ at $12 R_{{\\rm E}}$ (magnetosheath region). Despite the large cell size of the current version of the PIC code, it is powerful to retain macrostructure of planets magnetospheres in very short time, thus it can be used for pedagogical test purposes. It is also likely complementary with MHD to deepen our understanding of the large scale magnetosphere.

  13. Nonthermal ions and associated magnetic field behavior at a quasi-parallel earth's bow shock

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, W.P.; Schwartz, S.J.; Burgess, D. (Queen Mary and Westfield College, London (United Kingdom)); Pardaens, A.K. (Univ. of Sheffield (United Kingdom)); Luehr, H. (Technische Univ. Braunschweig (Germany)); Kessel, R.L. (Holmburt St. Mary, Dorking, Surrey (United Kingdom)); Dunlop, M.; Farrugia, C.J. (Imperial College of Science Technology and Medicine, London (Germany))

    1993-03-01

    Ion and magnetic field measurements at Earth's bow shock from the AMPTE-UKS and -IRM spacecraft, are examined in high time resolution during a 45-min interval when the field remained closely aligned with the model bow shock normal ([theta][sub Bn] [approximately] O[degrees]). Dense (> 1% of the solar wind phase space density) ion beams are detected almost exclusively in the midst of short-duration ([le] 30 s) periods of turbulent magnetic field wave activity. The maximum energy of the beams, which is comparable to the solar wind's energy, and their azimuthal location suggest that these ions may originate from specular-reflection off the shock. However, many examples of propagation at large elevation angles relative to the ecliptic plane are found, which is inconsistent with reflection in the standard model shock configuration. The associated waves span the frequency range between [approximately] 0.3 and 3 Hz. They are elliptically polarized, are preferentially left-handed in the observer's frame of reference, yet are less confined to the maximum variance plane than other previously studied foreshock waves. The angles of propagation of the waves with respect to the solar wind magnetic field (and shock normal) span a wide range of values but are typically [approximately] 30[degrees]. The considerable evolution in the appearance of the waves from one spacecraft to the other precludes us from estimating any of their properties in the plasma rest frame. Nevertheless, the association of the wave activity with the ion beams suggests that the former may be triggered by an ion-driven instability, and possible candidates are discussed. 53 refs., 9 figs., 3 tabs.

  14. Lithium and boron analysis by LA-ICP-MS results from a bowed PWR rod with contact

    Directory of Open Access Journals (Sweden)

    Puranen Anders

    2017-01-01

    Full Text Available A previously published investigation of an irradiated fuel rod from the Ringhals 2 PWR, which was bowed to contact with an adjacent rod, identified a significant but highly localised thinning of the clad wall and increased corrosion. Rod fretting was deemed unlikely due to the adhering oxide covering the surfaces. Local overheating in itself was also deemed insufficient to account for the accelerated corrosion. Instead, an enhanced concentration of lithium due to conditions of local boiling was hypothesised to explain the accelerated corrosion. Studsvik has developed a hot cell coupled LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometer equipment that enables a flexible means of isotopic analysis of irradiated fuel and other highly active surfaces. In this work, the equipment was used to investigate the distribution of lithium (7Li and boron (11B in the outer oxide at the bow contact area. Depth profiling in the clad oxide at the opposite side of the rod to the point of contact, which is considered to have experienced normal operating conditions and which has a typical oxide thickness, evidenced levels of ∼10–20 ppm 7Li and a 11B content reaching hundreds of ppm in the outer parts of the oxide, largely in agreement with the expected range of Li and B clad oxide concentrations from previous studies. In the contact area, the 11B content was similar to the reference condition at the opposite side. The 7Li content in the outermost oxide closest to the contact was, however, found to be strongly elevated, reaching several hundred ppm. The considerable and highly localised increase in lithium content at the area of enhanced corrosion thus offers strong evidence for a case of lithium induced breakaway corrosion during power operation, when rod-to-rod contact and high enough surface heat flux results in a very local increase in lithium concentration.

  15. Hubble Space Telescope Detection of the Millisecond Pulsar J2124-3358 and its Far-ultraviolet Bow Shock Nebula

    Science.gov (United States)

    Rangelov, B.; Pavlov, G. G.; Kargaltsev, O.; Reisenegger, A.; Guillot, S.; van Kerkwijk, M. H.; Reyes, C.

    2017-02-01

    We observed the nearby millisecond pulsar J2124–3358 with the Hubble Space Telescope in broad far-UV (FUV) and optical filters. The pulsar is detected in both bands with fluxes F(1250–2000 Å) = (2.5 ± 0.3) × 10‑16 erg s‑1 cm‑2 and F(3800–6000 Å) = (6.4 ± 0.4) × 10‑17 erg s‑1 cm‑2, which corresponds to luminosities of ≈5.8 × 1027 and 1.4 × 1027 erg s‑1, for d = 410 pc and E(B ‑ V) = 0.03. The optical-FUV spectrum can be described by a power-law model, {f}ν \\propto {ν }α , with slope α = 0.18–0.48 for a conservative range of color excess, E(B ‑ V) = 0.01–0.08. Since a spectral flux rising with frequency is unusual for pulsar magnetospheric emission in this frequency range, it is possible that the spectrum is predominantly magnetospheric (power law with α neutron star surface in the FUV. For a neutron star radius of 12 km, the surface temperature would be between 0.5 × 105 and 2.1 × 105 K for α ranging from ‑1 to 0, E(B ‑ V) = 0.01–0.08, and d = 340–500 pc. In addition to the pulsar, the FUV images reveal extended emission that is spatially coincident with the known Hα bow shock, making PSR J2124–3358 the second pulsar (after PSR J0437‑4715) with a bow shock detected in the FUV.

  16. Climate variability in the Carpathian Mountains Region over 1961-2010

    Science.gov (United States)

    Cheval, Sorin; Birsan, Marius-Victor; Dumitrescu, Alexandru

    2014-07-01

    The Carpathian Mountains Region (CMR) lies over parts of the territories of seven Central and Southeastern European countries, and the mountain chain induces major changes in the temperate climate specific to the latitudes between 43° and 49°N. Different administrations govern the long-term meteorological networks; the infrastructure, collection protocols, and storage capacities are specific to each country, so that a comprehensive study on the climate of the area has met considerable difficulties along time. Climate of the Carpathian Region (CARPATCLIM) is a regional initiative developed between 2010 and 2013 aiming to enhance the climatic information in the area by providing comprehensive, temporally and spatially homogenous data sets of the main meteorological variables. Based on daily data aggregated to a monthly scale at 10-km resolution, this study exploits and promotes the results of the CARPATCLIM project, documenting the variability of the main climatic variables over 1961-2010. For each month, the significant increasing or decreasing trends were identified, mapped and placed in the context of previous studies and climate change perspectives. The study has revealed several patterns in the climatic variability, i.e., positive or negative trends prevailing over the entire area, very distinct delineation between various trends induced by the Carpathian Mountain chain, and pledges for further scientific approaches, i.e., causes of the variability and applications in other domains.

  17. Venusian ion populations and bow shock as seen by the ASPERA-4 ion instrument on Venus Express

    Science.gov (United States)

    Grande, M.; Whittaker, I.; Guymer, G.; Barabash, S.

    2008-09-01

    Introduction We examine ion populations at Venus. Previous models use magnetic crossing points to derive the bow shock position. The current work uses data from the ASPERA-4 (Analyser of Space Plasmas and Energetic Atoms) [1] instrument to measure ion populations and derive a bow shock position at Venus. Instrumentation The ASPERA-4 instrument flies onboard Venus Express (VEX) and is comprised of five different detectors (Barabash et al 2006 [1]). A neutral particle detector and analyser, an electron spectrometer and the Ion Mass Analyser (IMA) (ref). This paper uses the IMA instrument for all its data and an explanation of the specifications is required. The instrument is a top hat electrostatic analyser; it runs through voltages to scan look angles and also acceptance energies. In one look direction it scans through 96 different energy values before changing to the next. A full scan of all look directions and energies takes 192 seconds. Data Collection All data is weighed dependant upon its probability of the spacecraft measuring at a particular point and when fitted produces a value of 1.24 RV, somewhat closer distance for the sub solar point than previous authors - see figure 1. We separate the data according to slow or fast solar wind and not the similarities and differences in the results derived. The inbound and outbound bow shock crossings were taken by inspection of 106 orbits between November 2006 and February 2007. Any orbits where the crossing point was not clear or with data missing were ignored. The occupational probability is found from orbital mechanics. By setting up a grid and deriving the amount of time it takes to cross each square the probability as a whole can then be determined. Ion distribution plots Two dimensional maps of the ions are produced and the bow shock model overplotted to verify its accuracy, as shown in figure 3. The test of the bow shock is to place it upon real data and examine the fit. To do this ion distribution plots are

  18. Best Practices Case Study: Pine Mountain Builders - Pine Mountain, GA

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-09-01

    Case study of Pine Mountain Builders who worked with DOE’s IBACOS team to achieve HERS scores of 59 on 140 homes built around a wetlands in Georgia. The team used taped rigid foam exterior sheathing and spray foam insulation in the walls and on the underside of the attic for a very tight 1.0 to 1.8 ACH 50 building shell.

  19. Microbial activity at Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Horn, J.M.; Meike, A.

    1995-09-25

    The U.S. Department of Energy is engaged in a suitability study for a potential geological repository at Yucca Mountain, Nevada, for the containment and storage of commercially generated spent fuel and defense high-level nuclear waste. There is growing recognition of the role that biotic factors could play in this repository, either directly through microbially induced corrosion (MIC), or indirectly by altering the chemical environment or contributing to the transport of radionuclides. As a first step toward describing and predicting these processes, a workshop was held on April 10-12, 1995, in Lafayette, California. The immediate aims of the workshop were: (1) To identify microbially related processes relevant to the design of a radioactive waste repository under conditions similar to those at Yucca Mountain. (2) To determine parameters that are critical to the evaluation of a disturbed subterranean environment. (3) To define the most effective means of investigating the factors thus identified.

  20. DISCONTINUITIES AND INADVERTENCES IN MOUNTAIN

    Directory of Open Access Journals (Sweden)

    VASILESCU RAMONA VIOLETA

    2013-05-01

    Full Text Available For some, mountain outings represent hikes; for some – rock climbing, and for others they consist of staying in a pension or hotel, while enjoying a pool in addition to the comfort of their home. This paper considers hiking enthusiasts, especially those who set off from their camp in the morning and return to their tent or nonluxurious accommodation in the evening.

  1. Water-resources reconnaissance of the Ouachita Mountains, Arkansas

    Science.gov (United States)

    Albin, Donald R.

    1965-01-01

    The Jenkins-Whitesburg area includes approximately 250 square miles in Letcher and Pike Counties in the southeastern part of the Eastern Coal Field. In this area ground water is the principal source of water for nearly all rural families, most public supplies, several coal mines and coal processing plants, and one bottling plant. The major aquifers in the Jenkins-Whitesburg area are the Breathitt and Lee Formations of Pennsylvanian age. Other aquifers range in age from Devonian to Quaternary but are not important in this area because they occur at great depth or yield little or no water. The Breathitt Formation occurs throughout the area except along the crest and slopes of Pine Mountain and where it is covered by unconsolidated material of Quaternary age. The Breathitt Formation consists of shale, sandstone, and lesser amounts of coal and associated underclay. The yield of wells penetrating the Breathitt Formation ranges from less than 1 to 330 gallons per minute. Well yield is controlled by the type and depth of well, character of the aquifer, and topography of the well site. Generally, deep wells drilled in valleys of perennial streams offer the best potential for high yields. Although enough water for a minimum domestic supply (more than 100 gallons per day) may be obtained from shale, all high-yielding wells probably obtain water from vertical joints and from bedding planes which are best developed in sandstone. About 13 percent of the wells inventoried in the Breathitt Formation failed to supply enough water for a minimum domestic supply. Most of these are shallow dug wells or drilled wells on hillsides or hilltops. Abandoned coal mines are utilized as large infiltration galleries and furnish part of the water for several public supplies. The chemical quality of water from the Breathitt Formation varies considerably from place to place, but the water generally is acceptable for most domestic and industrial uses. Most water is a calcium magnesium bicarbonate

  2. On the Mountain Urban Landscape Studies

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Mountain Urban Landscape Studies is a discipline to research on the formation,evolution and characteristics of the urban landscape in mountainous areas. The author has made systematic research on the basic issues of the subject,including the definition of mountain urban landscape studies,its connotation and denotation,the research scope,research background and significance,research methodology,its relationship with landscape architecture,architecture,city planning and other disciplines.

  3. Location Awareness in a Mountain Rescue Domain

    OpenAIRE

    Georgopoulos, Panagiotis; Edwards, Christopher; Dunmore, Martin

    2008-01-01

    Aiding the efficient collaboration and coordination of rescue teams is a challenging task especially in a heterogeneous mountainous region. Knowing the exact location of the rescuers during a mountain search and rescue mission can be of great value for the successful progress of the mission and help the mission coordinator in taking informed decisions. The devised Location Awareness System can provide, in a quasi real time manner, exact location information of the rescuers on the mountain, to...

  4. Resources, tourism and mountain territorial development

    Directory of Open Access Journals (Sweden)

    2012-02-01

    Full Text Available Rationale and objectivesThe Journal of Alpine Research is preparing a special issue dedicated to the theme “Resources”, tourism and mountain territorial development.” The objective is to bring together analyses concerning the identification, “invention,” communication and exploitation of territorial resources in development initiatives including tourism in African and European mountainous regions, or beyond. It will particularly stress the capacity of referring to “mountains,” as a generic ca...

  5. On the Mountain Urban Landscape Studies

    Institute of Scientific and Technical Information of China (English)

    DU ChunLan

    2009-01-01

    Mountain Urban Landscape Studies is a discipline to research on the formation, evolution and char-acteristics of the urban landscape in mountainous areas. The author has made systematic research on the basic issues of the subject, including the definition of mountain urban landscape studies, its con-notation and denotation, the research scope, research background and significance, research meth-odology, its relationship with landscape architecture, architecture, city planning and other disciplines.

  6. Ecosystem vulnerability to climate change in the southeastern United States

    Science.gov (United States)

    Cartwright, Jennifer M.; Costanza, Jennifer

    2016-08-11

    Two recent investigations of climate-change vulnerability for 19 terrestrial, aquatic, riparian, and coastal ecosystems of the southeastern United States have identified a number of important considerations, including potential for changes in hydrology, disturbance regimes, and interspecies interactions. Complementary approaches using geospatial analysis and literature synthesis integrated information on ecosystem biogeography and biodiversity, climate projections, vegetation dynamics, soil and water characteristics, anthropogenic threats, conservation status, sea-level rise, and coastal flooding impacts. Across a diverse set of ecosystems—ranging in size from dozens of square meters to thousands of square kilometers—quantitative and qualitative assessments identified types of climate-change exposure, evaluated sensitivity, and explored potential adaptive capacity. These analyses highlighted key gaps in scientific understanding and suggested priorities for future research. Together, these studies help create a foundation for ecosystem-level analysis of climate-change vulnerability to support effective biodiversity conservation in the southeastern United States.

  7. Population densities of painted buntings in the southeastern United States

    Science.gov (United States)

    Meyers, J. Michael

    2011-01-01

    The eastern population trend of Passerina ciris (Painted Bunting) declined 3.5% annually during the first 30 yrs of the Breeding Bird Survey (BBS, 1966–1996). Recently, the US Fish and Wildlife Service listed Painted Buntings as a focal species. Surveys for this focal species for the next 10 yrs (BBS, 1997–2007), however, are too low (2 in young pine plantations to 42 per km2 in maritime shrub. Effective detection radii for habitats varied from 64 to 90 m and were slightly higher in developed than in undeveloped habitats. Distance sampling is recommended to determine densities of Painted Buntings; however, large sample sizes (70–100 detections/habitat type) are required to monitor Painted Bunting densities in most habitats in the Atlantic coastal region of the southeastern United States. Special attention should be given to maritime shrub habitats, which may be important to maintaining the Painted Bunting population in the southeastern US.

  8. Cluster analysis of Southeastern U.S. climate stations

    Science.gov (United States)

    Stooksbury, D. E.; Michaels, P. J.

    1991-09-01

    A two-step cluster analysis of 449 Southeastern climate stations is used to objectively determine general climate clusters (groups of climate stations) for eight southeastern states. The purpose is objectively to define regions of climatic homogeneity that should perform more robustly in subsequent climatic impact models. This type of analysis has been successfully used in many related climate research problems including the determination of corn/climate districts in Iowa (Ortiz-Valdez, 1985) and the classification of synoptic climate types (Davis, 1988). These general climate clusters may be more appropriate for climate research than the standard climate divisions (CD) groupings of climate stations, which are modifications of the agro-economic United States Department of Agriculture crop reporting districts. Unlike the CD's, these objectively determined climate clusters are not restricted by state borders and thus have reduced multicollinearity which makes them more appropriate for the study of the impact of climate and climatic change.

  9. Mitochondrial DNA Variation in Southeastern Pre-Columbian Canids.

    Science.gov (United States)

    Brzeski, Kristin E; DeBiasse, Melissa B; Rabon, David R; Chamberlain, Michael J; Taylor, Sabrina S

    2016-05-01

    The taxonomic status of the red wolf (Canis rufus) is heavily debated, but could be clarified by examining historic specimens from the southeastern United States. We analyzed mitochondrial DNA (mtDNA) from 3 ancient (350-1900 year olds) putative wolf samples excavated from middens and sinkholes within the historic red wolf range. We detected 3 unique mtDNA haplotypes, which grouped with the coyote mtDNA clade, suggesting that the canids inhabiting southeastern North America prior to human colonization from Europe were either coyotes, which would vastly expand historic coyote distributions, an ancient coyote-wolf hybrid, or a North American evolved red wolf lineage related to coyotes. Should the red wolf prove to be a distinct species, our results support the idea of either an ancient hybrid origin for red wolves or a shared common ancestor between coyotes and red wolves.

  10. INTERNET ADDICTION IN BALKAN AND SOUTH-EASTERN EUROPEAN COUNTRIES

    Directory of Open Access Journals (Sweden)

    Ioannis PETASAKIS

    2012-12-01

    Full Text Available The use of Internet has increased dramatically in recent years. Although there is no standardized definition of Internet addiction, there is acknowledgement among researchers that this phenomenon does exist. In this study, we identify various similarities and differences among people in the Balkan and South-Eastern European countries about Internet addiction. There are many factors such as cultural differences, gender differences, psychosocial variables, computer attitudes and time.We present the experience from studies concerning Internet addiction in all over the world. A specific research with the use of Young's 20-scale was also conducted in five Balkan and South-Eastern European countries (Republic of Moldova, Romania, Republic of Bulgaria, Hellenic Republic, Republic of Cyprus.The findings are interesting. Although there is a need for Interest using, there are also cases where the addiction, dependence and abuse is apparent.

  11. Fouffeen Mountain Summits:the Dreams and Glory of Chinese Mountaineers

    Institute of Scientific and Technical Information of China (English)

    DORJE; DRADUL

    2007-01-01

    As the first mountaineering team to challenge the fourteen world's highest mountain summits,these Chinese mountaineers have finally realized their dream.They are all ethnic Tibetans and have gone through hardship and dangers over the years;some of them have even contributed their lives to the realization of the project.Finally,three of them have accomplished it and set a marvelous record in world mountaineering that is unprecedented.

  12. MICROMORPHOLOGY AND PEDOGENESIS OF MOUNTAINOUS INCEPTISOLS IN THE MANTIQUEIRA RANGE (MG

    Directory of Open Access Journals (Sweden)

    Leandro Campos Pinto

    2015-10-01

    Full Text Available ABSTRACTUnderstanding soil formation processes across different landscapes is needed to predict how soil properties will respond to land use change. This study aimed to characterize mountainous Inceptisols (Cambisols under high altitude subtropical climate in southeastern Brazil, by soil physical, chemical and micromorphological analyses, under native forest and pasture. The soil under pasture had a greater bulk density than under forest, resulting in a severe reduction of macroporosity. At two depths, coarse quartz grains are angular, suggesting absence of transportational processes, thus confirming an autochthonous pedogenesis from the underlying gneissic rock. Most feldspars were weathered beyond recognition, but mineral alteration was commonly seen across cleavage plans and edges of micas. The micromorphological results suggest an intermediate stage of mineral weathering and soil development, which is in accordance with properties expected to be found in Inceptisols.

  13. Landscape, Mountain Worship and Astronomy in Socaire

    Science.gov (United States)

    Moyano, Ricardo

    The spatiotemporal analysis of mountain worship in the indigenous community of Socaire, Atacama, northern Chile, relates to cultural, geographical, climatic, psychological, and astronomical information gathered from ethno archaeological studies. We identify a system of offerings to the mountains that incorporates concepts such as ceque (straight line), mayllku (mountain lord or ancestor), and pacha (space and time). Here, the mountains on the visible horizon (Tumisa, Lausa, Chiliques, Ipira, and Miñiques) feature as the fingers on the left hand (PAH Triad). This structure regulates annual activities and rituals and sets the basis for the Socaireños' worldview raised on a humanized landscape.

  14. Ticks and spotted fever group rickettsiae of southeastern Virginia.

    Science.gov (United States)

    Nadolny, Robyn M; Wright, Chelsea L; Sonenshine, Daniel E; Hynes, Wayne L; Gaff, Holly D

    2014-02-01

    The incidence of tick-borne rickettsial disease in the southeastern United States has been rising steadily through the past decade, and the range expansions of tick species and tick-borne infectious agents, new and old, has resulted in an unprecedented mix of vectors and pathogens. The results of an ongoing 4-year surveillance project describe the relative abundance of questing tick populations in southeastern Virginia. Since 2009, more than 66,000 questing ticks of 7 species have been collected from vegetation in a variety of habitats, with Amblyomma americanum constituting over 95% of ticks collected. Other species represented included Ixodes scapularis, Dermacentor variabilis, Amblyomma maculatum, Ixodes affinis, Haemaphysalis leporispalustris, and Ixodes brunneus. We found that 26.9-54.9% of A. americanum ticks tested were positive for Rickettsia amblyommii, a non-pathogenic symbiont of this tick species. We also found no evidence of R. rickettsii in D. variabilis ticks, although they did show low infection rates of R. montanensis (1.5-2.0%). Rickettsia parkeri and Candidatus R. andeanae were found in 41.8-55.7% and 0-1.5% A. maculatum ticks, respectively. The rate of R. parkeri in A. maculatum ticks is among the highest in the literature and has increased in the 2 years since R. parkeri and A. maculatum were first reported in southeastern Virginia. We conclude that tick populations in southeastern Virginia have recently undergone dramatic changes in species and abundance and that these populations support a variety of rickettsial agents with the potential for increased risk to human health.

  15. National Uranium Resource Evaluation. Volume 1. Summary of the geology and uranium potential of Precambrian conglomerates in southeastern Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Karlstrom, K.E.; Houston, R.S.; Flurkey, A.J.; Coolidge, C.M.; Kratochvil, A.L.; Sever, C.K.

    1981-02-01

    A series of uranium-, thorium-, and gold-bearing conglomerates in Late Archean and Early Proterozoic metasedimentary rocks have been discovered in southern Wyoming. The mineral deposits were found by applying the time and strata bound model for the origin of uranium-bearing quartz-pebble conglomerates to favorable rock types within a geologic terrane known from prior regional mapping. No mineral deposits have been discovered that are of current (1981) economic interest, but preliminary resource estimates indicate that over 3418 tons of uranium and over 1996 tons of thorium are present in the Medicine Bow Mountains and that over 440 tons of uranium and 6350 tons of thorium are present in Sierra Madre. Sampling has been inadequate to determine gold resources. High grade uranium deposits have not been detected by work to date but local beds of uranium-bearing conglomerate contain as much as 1380 ppM uranium over a thickness of 0.65 meters. This project has involved geologic mapping at scales from 1/6000 to 1/50,000 detailed sampling, and the evaluation of 48 diamond drill holes, but the area is too large to fully establish the economic potential with the present information. This first volume summarizes the geologic setting and geologic and geochemical characteristics of the uranium-bearing conglomerates. Volume 2 contains supporting geochemical data, lithologic logs from 48 drill holes in Precambrian rocks, and drill site geologic maps and cross-sections from most of the holes. Volume 3 is a geostatistical resource estimate of uranium and thorium in quartz-pebble conglomerates.

  16. Possible Late Quaternary faulting in the Benton Hills, southeastern Missouri

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, J.R.; Hoffman, D. (Missouri Geological Survey Program, Rolla, MO (United States). Dept. of Natural Resources)

    1993-03-01

    Geologic mapping in the 1930's by Dan Stewart and Lyle McManamy identified numerous faults in the Thebes Gap area of the Benton Hills, including two post-late Quaternary faults (max. of 10 m displacement) along the southeastern escarpment. Recent geologic mapping (Richard Harrison, pers. comm.) suggests dextral strike-slip displacement on most of these faults; some deformation post-dates the Pliocene-Pleistocene Mounds gravel. Small historical earthquake epicenters have been recorded in the Benton Hills area. Review of these data and analysis of the geologic and structural relationships to small- and large-scale drainage and alluvial features suggest tectonic control of the southeastern escarpment of the Benton Hills. The authors propose the coincidence of geologic structures and landforms resembles tectonically active alluvial basin margins, with the Benton Hills southeastern margin representing a fault block uplift escarpment. Future seismic reflection, drilling and trenching studies are planned to determine if the escarpment is fault controlled and of recent origin.

  17. Mechanism of the Spring Persistent Rains over southeastern China

    Institute of Scientific and Technical Information of China (English)

    WAN RiJin; WU GuoXiong

    2007-01-01

    The Spring Persistent Rains (SPR) in the areas to the south of middle and lower reaches of the Yangtze River or over southeastern China (SEC) is a unique synoptic and climatic phenomenon in East Asia. This study reveals a possible mechanism responsible for the climatic cause of SPR formation through climatic mean data analysis and sensitive numerical model experiments. SEC is located at the downstream of the southwesterly velocity center (SWVC) which lies on the southeastern flank of the Tibetan Plateau (TP). As a result, there are strong southwesterly wind velocity convergence and moisture convergence over SEC. This is the immediate climatic cause of SPR formation. In spring, the seasonal evolution of the southwesterly velocity consists with the surface sensible heating over southeastern TP, indicating that the formation of SPR is related to not only the southwesterly wind of mechanical deflected flow of TP, but also the southwesterly wind of thermal-forced cyclonic low circulation. Sensitive numerical experiments demonstrate that, without TP, both SWVC and the SPR rain belt will disappear. The southwesterly wind velocity increases almost linearly with the amount of the total diabatic heating with TP rising. Therefore, SWVC is the result of the mechanical forcing and thermal forcing of TP. All these strongly suggest that the presence of TP plays a primary role in the climatic formation of SPR.

  18. Mechanism of the Spring Persistent Rains over southeastern China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Spring Persistent Rains (SPR) in the areas to the south of middle and lower reaches of the Yangtze River or over southeastern China (SEC) is a unique synoptic and climatic phenomenon in East Asia. This study reveals a possible mechanism responsible for the climatic cause of SPR formation through climatic mean data analysis and sensitive numerical model experiments. SEC is located at the down-stream of the southwesterly velocity center (SWVC) which lies on the southeastern flank of the Tibetan Plateau (TP). As a result, there are strong southwesterly wind velocity convergence and moisture con-vergence over SEC. This is the immediate climatic cause of SPR formation. In spring, the seasonal evolution of the southwesterly velocity consists with the surface sensible heating over southeastern TP, indicating that the formation of SPR is related to not only the southwesterly wind of mechanical de-flected flow of TP, but also the southwesterly wind of thermal-forced cyclonic low circulation. Sensitive numerical experiments demonstrate that, without TP, both SWVC and the SPR rain belt will disappear. The southwesterly wind velocity increases almost linearly with the amount of the total diabatic heating with TP rising. Therefore, SWVC is the result of the mechanical forcing and thermal forcing of TP. All these strongly suggest that the presence of TP plays a primary role in the climatic formation of SPR.

  19. Possible Impact of climate change on future extreme precipitation of the Oldman, Bow and Red Deer River Basins of Alberta

    Science.gov (United States)

    Yew Gan, Thian; Gizaw, Mesgana

    2016-04-01

    The impact of climate change on extreme precipitation events in the Oldman (ORB), Bow, (BRB) and Red Deer (RRB) River Basins of southern Alberta, Canada, was assessed using six extreme climate indices for the rainy period of May-August (MJJA), and 9-km resolution Special Report on Emission Scenarios (SRES) A2 and A1B climate scenarios of four Coupled Model Intercomparison Project Phase 3 (CMIP3) Global Climate Models (GCMs) dynamically downscaled by a regional climate model, MM5. R95p of the three study sites showed an increase of 4% for the 2050s (2041-2070) and 10% for the 2080s (2071-2100) period, whereas R99p increased by 39% (2050s) and 42% (2080s) which suggest a projected increase in the volume of precipitation expected in future very wet and particularly extremely wet days. Similarly, R20mm, P30yr, RX1day and RX5day are also projected to increase by about 15% by the mid- and late 21st century in the three study sites. However, compared to BRB and RRB, ORB located in the southernmost part of the study site is projected to undergo a relatively higher increase in both temperature and precipitation intensity, which is assessed in terms of indices such as P30yr, RX1day and RX5day. On the other hand, RRB and BRB are projected to experience higher increase in R20mm, which suggest a relatively higher increase in the number of very heavy precipitation days projected for these two basins. Overall, these results suggest that in the 2050s and 2080s, southern Alberta will be expected to experience more frequent and severe intensive storm events in the MJJA season that could potentially increase the risk of future flooding in this region. Ref: Gizaw, M., and Gan, T. Y., 2015, Possible Impact of climate change on future extreme precipitation of the Oldman, Bow and Red Deer River Basins of Alberta, Int. Journal Climatology, DOI:10.1002/joc.4338

  20. THE CHESS SURVEY OF THE L1157-B1 SHOCK REGION: CO SPECTRAL SIGNATURES OF JET-DRIVEN BOW SHOCKS

    Energy Technology Data Exchange (ETDEWEB)

    Lefloch, B.; Codella, C.; Ceccarelli, C. [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et dAstrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Cabrit, S. [Observatoire de Paris, LERMA, UMR 8112 du CNRS, ENS, UPMC, UCP, 61 Av. de l' Observatoire, F-75014 Paris (France); Busquet, G.; Benedettini, M. [INAF, Istituto di Astrofisica e Planetologia Spaziali, Via Fosso del Cavaliere 100, I-00133 Roma (Italy); Cernicharo, J.; Pardo, J. R. [Centro de Astrobiologia, INTA, Ctra de Torrejon a Ajalvir, km 4, E-28850 Torrejon de Ardoz, E-28850 Madrid (Spain); Lis, D. C. [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States); Nisini, B., E-mail: lefloch@obs.ujf-grenoble.fr [INAF, Osservatorio Astronomico di Roma, Via di Frascati 33, I-00040 Monte, Porzio Catone (Italy)

    2012-10-01

    The unprecedented sensitivity of Herschel coupled with the high resolution of the HIFI spectrometer permits studies of the intensity-velocity relationship I(v) in molecular outflows, over a higher excitation range than possible up to now. Over the course of the CHESS Key Program, we have observed toward the bright bow shock region L1157-B1, the CO rotational transitions between J = 5-4 and J = 16-15 with HIFI, and the J = 1-0, 2-1, and 3-2 with the IRAM 30 m and the Caltech Submillimeter Observatory telescopes. We find that all the line profiles I{sub CO}(v) are well fit by a linear combination of three exponential laws {proportional_to}exp (- |v/v{sub 0}|) with v{sub 0} = 12.5, 4.4, and 2.5 km s{sup -1}. The first component dominates the CO emission at J {>=} 13, as well as the high-excitation lines of SiO and H{sub 2}O. The second component dominates for 3 {<=} J{sub up} {<=} 10 and the third one for J{sub up} {<=} 2. We show that these exponentials are the signature of quasi-isothermal shocked gas components: the impact of the jet against the L1157-B1 bow shock (T{sub k} {approx_equal} 210 K), the walls of the outflow cavity associated with B1 (T{sub k} {approx_equal} 64 K), and the older cavity L1157-B2 (T{sub k} {approx_equal} 23 K), respectively. Analysis of the CO line flux in the large-velocity gradient approximation further shows that the emission arises from dense gas (n(H{sub 2}) {>=} 10{sup 5}-10{sup 6} cm{sup -3}) close to LTE up to J = 20. We find that the CO J = 2-1 intensity-velocity relation observed in various other molecular outflows is satisfactorily fit by similar exponential laws, which may hold an important clue to their entrainment process.

  1. First measurements with a new 6m long violin-bow marine heat probe off Costa Rica

    Science.gov (United States)

    Gennerich, H.-H.; Grevemeyer, I.; Heesemann, B.; Heesemann, M.; Kaul, N.; Müller, M.; Villinger, H.

    2003-04-01

    The design of a new 6m long violin-bow marine heat probe, first successful tests and data collected off Costa Rica during cruise M54-2 on RV METEOR in August 2002 are presented. The mechanically robust heat probe is designed for the operation in a pogo-style mode with a wide application range from 6000m deep sea trenches with mostly soft sediments to the upper continental slope where sediments are often sandy and difficult to penetrate. Due to the 6m length of its temperature sensor string undisturbed temperature gradients can be determined in shallow water with seasonal bottom water temperature variations. The heat probe is constructed in the classical "violin bow" design, with 22 thermistors equidistantly distributed inside an oil filled hydraulic tube attached to the strength member. The sensor tube also contains a heater wire for the generation of a calibrated heat pulse for in situ thermal conductivity measurements. The signal of the temperature sensors is measured with a resolution of 20-bits at a sample rate of 1 sec, resulting in a final temperature resolution of less than 1 mK at ambient sea floor temperatures. A carefully calibrated seawater sensor on top of the weight stand allows to measure the absolute bottom water temperature. Inclination and acceleration of the probe is measured also with a 1 sec sample rate to monitor the penetration process into the sediments and potential disturbances during the measurement period while the probe sits in the sediment. Data from a pressure sensor in conjunction with an acoustic altimeter allow the exact absolute measurement of the final penetration depth of the probe. The complete data set is stored in the probe but also transmitted via coax cable on board in real time which allows operational decisions during long term deployments of the probe. In addition the heat probe can be operated in a completely autonomous mode with internal storage and automated heat pulses. The battery capacity allows for 3 days

  2. Experimental validation of a method characterizing bow tie filters in CT scanners using a real-time dose probe

    Energy Technology Data Exchange (ETDEWEB)

    McKenney, Sarah E.; Nosratieh, Anita; Gelskey, Dale; Yang Kai; Huang Shinying; Chen Lin; Boone, John M. [Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Rm. 2303, GBSF, 451 E. Health Science Dr., Davis, California 95616 (United States); Diagnostic Imaging Specialists Corporation (DISC), 163 St. Malo Street, St. Malo, Manitoba R0A 1T0 (Canada); Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States); Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Rm. 2303, GBSF, 451 E. Health Science Dr., Davis, California 95616 (United States)

    2011-03-15

    Purpose: Beam-shaping or ''bow tie'' (BT) filters are used to spatially modulate the x-ray beam in a CT scanner, but the conventional method of step-and-shoot measurement to characterize a beam's profile is tedious and time-consuming. The theory for characterization of bow tie relative attenuation (COBRA) method, which relies on a real-time dosimeter to address the issues of conventional measurement techniques, was previously demonstrated using computer simulations. In this study, the feasibility of the COBRA theory is further validated experimentally through the employment of a prototype real-time radiation meter and a known BT filter. Methods: The COBRA method consisted of four basic steps: (1) The probe was placed at the edge of a scanner's field of view; (2) a real-time signal train was collected as the scanner's gantry rotated with the x-ray beam on; (3) the signal train, without a BT filter, was modeled using peak values measured in the signal train of step 2; and (4) the relative attenuation of the BT filter was estimated from filtered and unfiltered data sets. The prototype probe was first verified to have an isotropic and linear response to incident x-rays. The COBRA method was then tested on a dedicated breast CT scanner with a custom-designed BT filter and compared to the conventional step-and-shoot characterization of the BT filter. Using basis decomposition of dual energy signal data, the thickness of the filter was estimated and compared to the BT filter's manufacturing specifications. The COBRA method was also demonstrated with a clinical whole body CT scanner using the body BT filter. The relative attenuation was calculated at four discrete x-ray tube potentials and used to estimate the thickness of the BT filter. Results: The prototype probe was found to have a linear and isotropic response to x-rays. The relative attenuation produced from the COBRA method fell within the error of the relative attenuation

  3. Simulated solar wind plasma interaction with the Martian exosphere: influence of the solar EUV flux on the bow shock and the magnetic pile-up boundary

    Directory of Open Access Journals (Sweden)

    R. Modolo

    2006-12-01

    Full Text Available The solar wind plasma interaction with the Martian exosphere is investigated by means of 3-D multi-species hybrid simulations. The influence of the solar EUV flux on the bow shock and the magnetic pile-up boundary is examined by comparing two simulations describing the two extreme states of the solar cycle. The hybrid formalism allows a kinetic description of each ions species and a fluid description of electrons. The ionization processes (photoionization, electron impact and charge exchange are included self-consistently in the model where the production rate is computed locally, separately for each ionization act and for each neutral species. The results of simulations are in a reasonable agreement with the observations made by Phobos 2 and Mars Global Surveyor spacecraft. The position of the bow shock and the magnetic pile-up boundary is weakly dependent of the solar EUV flux. The motional electric field creates strong asymmetries for the two plasma boundaries.

  4. Modeling of the wafer bow in GaN-on-Si epiwafers employing GaN/AlN multilayer buffer structures

    Science.gov (United States)

    Miyoshi, Makoto; Watanabe, Arata; Egawa, Takashi

    2016-10-01

    We built a calculation model for the wafer bow in GaN-on-Si epiwafers employing GaN/AlN multilayer (ML) buffer structures by extending Stoney’s equation. The calculated bow and the derived strain in the epilayers were almost consistent with experimental results. The calculation quantitatively revealed that the ML buffers introduced an in-plane compressive stress in the epitaxial structures. Also, relationships between the epiwafer bow and the stress in the respective layers became clear to a certain extent. For instance, when considering the case where periodic structures with 20 nm thick GaN/5 nm thick AlN pairs were grown as ML buffers on 4-in.-diameter and 525 μm thick Si (111) substrates at a growth temperature (T g) of 1125 °C, the stress in the MLs was derived to be 2.18 GPa in the in-plane compressive direction in the GaN layers and 5.89 GPa in the in-plane tensile direction in the AlN layers at T g. Although magnitude of the in-plane stress in the GaN layers is obviously smaller than that in the AlN layers, the restoring force generated in the GaN layers becomes larger than that in the AlN layers, because the force is in proportion to the layer thickness rather than to just the stress. As a consequence, the generated stress in the MLs was considered to produce enough force to suppress the epiwafer bow. The calculation also demonstrated that GaN epilayers on GaN/AlN MLs were strained in the in-plane compressive direction at T g and almost strain-free at room temperature.

  5. Cascade Mountain Range in Oregon

    Science.gov (United States)

    Sherrod, David R.

    2016-01-01

    The Cascade mountain system extends from northern California to central British Columbia. In Oregon, it comprises the Cascade Range, which is 260 miles long and, at greatest breadth, 90 miles wide (fig. 1). Oregon’s Cascade Range covers roughly 17,000 square miles, or about 17 percent of the state, an area larger than each of the smallest nine of the fifty United States. The range is bounded on the east by U.S. Highways 97 and 197. On the west it reaches nearly to Interstate 5, forming the eastern margin of the Willamette Valley and, farther south, abutting the Coast Ranges. 

  6. OS X Mountain Lion bible

    CERN Document Server

    Gruman, Galen

    2012-01-01

    The complete guide to Mac OS X, fully updated for the newest release! The Mac's solid, powerful operating system and the exploding popularity of iOS devices are fueling a strong increase in market share for Apple. Previous editions of this book have sold more than 75,000 copies, and this new edition is fully updated with all the exciting features of OS X Mountain Lion, including Game Center, Messages, and Notifications. Written by industry expert Galen Gruman, it covers all the basics and then delves deep into professional and higher-end topics, making it the one book you need to succeed with

  7. Neogene sinistral transtension along the Hickman fault zone, southeastern Colorado Plateau, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Chamberlin, R.M. (New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States))

    1993-04-01

    A north-northeast-trending crustal flaw known as the Hickman fault zone (HFZ) transects the southeastern margin of the Colorado Plateau from Mangas to Grants, New Mexico, a distance of 140 km. Recent reconnaissance mapping of the eastern half of the Quemado 1:100,000 sheet by the author indicates that the southern half of the HFZ is a Neogene oblique-slip zone that displays a normal-sinistral sense of shear. The vertical slip component is 150--200 m and the apparent horizontal component is as much as 120 m. Basaltic debris flows and fluvial deposits of the Miocene Fence Lake Formation are preferentially preserved on the downthrown western side of the HFZ. West of Pietown, Fence Lake strata define an asymmetric synclinal basin. Older northwest-striking Late Oligocene basaltic dikes are locally concealed where they pass under the shallow (200 m) northeast--trending basin. Within the 5-km-wide HFZ, north-trending segments appear to form releasing bends and east-northeast-trending segments appear to form weakly constraining bends, a pattern that implies distributed sinistral shear. Small alluvial basins (incipient half grabens) in the Mangas Mountains are associated with north-striking bends. An east-northeast-trending bend near Pietown is locally defined by an asymmetric anticline; also the Late Oligocene dike trend here bends westerly (counterclockwise) where it crosses the anticlinal axis. Near Hickman (a.k.a. Lehew), the HFZ shows two sinistral offsets of another Late Oligocene dike; cumulative offset is about 120 m.

  8. Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

    Directory of Open Access Journals (Sweden)

    Adrian Indreica

    2011-02-01

    Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Braşov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate,for a better management of sessile oak forests with spruce admixture.

  9. Seed predation and climate impacts on reproductive variation in temperate forests of the southeastern USA.

    Science.gov (United States)

    Bell, David M; Clark, James S

    2016-04-01

    Climatic effects on tree recruitment will be determined by the interactive effects of fecundity and seed predation. Evaluating how insect and vertebrate seed predators mediate tree reproductive responses to climate depends on long-term studies of seed production, development, and predation. In this study, our objectives were to (1) assess the effects of interannual climate variation on seed abortion rates, (2) assess the impact of seed density on predation rates, and (3) examine the degree to which density-dependent seed predation would amplify or dampen interannual variation in fecundity associated with seed abortion. We used a 19-year study of seed abortion and pre-dispersal predation rates by insects and vertebrates (birds and rodents) for five temperate tree species across forest plots from the North Carolina Piedmont to the Southern Appalachian Mountains in the southeastern USA. We found that rates of seed abortion and predation increased reproductive variation for oaks (Quercus species). Probability of seed abortion was greatest during years with cool, dry springs. Responses of seed predation on Quercus species to current year's seed density varied by species, but exhibited positive density-dependence to previous year's seed density consistent with numerical responses of seed predators. Seed abortion and predation rates for two drupe species responded little to variation in climate or seed density, respectively. Given that predation increased interannual variation in seed availability and the negative density-dependence to previous year's seed density, our results indicate that consistent numerical responses of oak seed predators may amplify interannual variation due to climate-mediated processes like seed abortion.

  10. Siphonaptera parasites of wild rodents and marsupials trapped in three mountain ranges of the Atlantic Forest in Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Leandro Bianco de Moraes

    2003-12-01

    Full Text Available A study of the associations between small mammals and fleas was undertaken in three areas of the Atlantic Forest in Souhtheastern Brazil: Serra da Fartura, SP, Serra da Bocaina, SP, and Itatiaia, RJ. Trapping of small rodents and marsupials was done every 3 months during 2 years, from June 1999 to May 2001. A total 502 rodents (13 species and 50 marsupials (7 species were collected, and 185 hosts out of 552 (33.5% captured in the traps were parasitized by 327 fleas belonging to 11 different species. New host records were determined for several flea species, and 5 significant associations between fleas and hosts were also found.

  11. Geographic Layers as Landscape Drivers for the Marco Polo Argali Habitat in the Southeastern Pamir Mountains of Tajikistan

    Directory of Open Access Journals (Sweden)

    Eric Ariel L. Salas

    2015-10-01

    Full Text Available We described in this report the essential geographic layers used as landscape drivers for the Marco Polo Argali habitat in the eastern Tajik Pamirs. Using remote sensing techniques and geographic information systems (GIS, individual layers were generated in order to acquire more information on argali patterns and habitat suitability and to make the dataset available online. We introduced an improved object-based image analysis in our mapping of the vegetation cover by utilizing spectral, topographic, and texture variables. We exhausted every Landsat image band and texture feature combination to select the best pairing of band-texture components. For vegetation class alone, the producer’s accuracy was 90.8% and the user’s accuracy was 91.6%.

  12. A Bow Shock Nebula Around a Compact X-Ray Source in the Supernova Remnant IC443

    CERN Document Server

    Olbert, C M; Williams, N E; Keohane, J W; Frail, D A

    2001-01-01

    We present spectra and high resolution images of the hard X-ray feature along the southern edge of the supernova remnant IC443. Data from the Chandra X-ray Observatory reveal a comet-shaped nebula of hard emission, which contains a softer point source at its apex. We also present 20cm, 6cm, and 3.5cm images from the Very Large Array that clearly show the cometary nebula. Based on the radio and X-ray morphology and spectrum, and the radio polarization properties, we argue that this object is a synchrotron nebula powered by the compact source that is physically associated with IC443. The spectrum of the soft point source is adequately but not uniquely fit by a black body model (kT=0.71 +/- 0.08 keV, L=(6.5 +/- 0.9) * 10^31 erg/s). The cometary morphology of the nebula is the result of the supersonic motion of the neutron star (V_NS=250 +/- 50 km/s), which causes the relativistic wind of the pulsar to terminate in a bow shock and trail behind as a synchrotron tail. This velocity is consistent with an age of 30,0...

  13. Direct measurement of the cross-shock electric potential at low plasma $\\beta$, quasi-perpendicular bow shocks

    CERN Document Server

    Bale, S D; Krasnoselskikh, V V

    2008-01-01

    We use the Cluster EFW experiment to measure the cross-shock electric field at ten low $\\beta$, quasi-perpendicular supercritical bow shock crossings on March 31, 2001. The electric field data are Lorentz-tranformed to a Normal Incidence frame (NIF), in which the incoming solar wind velocity is aligned with the shock normal. In a boundary normal coordinate system, the cross-shock (normal) electric field is integrated to obtain the cross shock potential. Using this technique, we measure the cross-shock potential at each of the four Cluster satellites and using an electric field profile averaged between the four satellites. Typical values are in the range 500-2500 volts. The cross-shock potential measurements are compared with the ion kinetic energy change across the shock. The cross-shock potential is measured to be from 23 to 236% of the ion energy change, with large variations between the four Cluster spacecraft at the same shock. These results indicate that solar wind flow through the shock is likely to be ...

  14. A bow-tie genetic architecture for morphogenesis suggested by a genome-wide RNAi screen in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Matthew D Nelson

    2011-03-01

    Full Text Available During animal development, cellular morphogenesis plays a fundamental role in determining the shape and function of tissues and organs. Identifying the components that regulate and drive morphogenesis is thus a major goal of developmental biology. The four-celled tip of the Caenorhabditis elegans male tail is a simple but powerful model for studying the mechanism of morphogenesis and its spatiotemporal regulation. Here, through a genome-wide post-embryonic RNAi-feeding screen, we identified 212 components that regulate or participate in male tail tip morphogenesis. We constructed a working hypothesis for a gene regulatory network of tail tip morphogenesis. We found regulatory roles for the posterior Hox genes nob-1 and php-3, the TGF-β pathway, nuclear hormone receptors (e.g. nhr-25, the heterochronic gene blmp-1, and the GATA transcription factors egl-18 and elt-6. The majority of the pathways converge at dmd-3 and mab-3. In addition, nhr-25 and dmd-3/mab-3 regulate each others' expression, thus placing these three genes at the center of a complex regulatory network. We also show that dmd-3 and mab-3 negatively regulate other signaling pathways and affect downstream cellular processes such as vesicular trafficking (e.g. arl-1, rme-8 and rearrangement of the cytoskeleton (e.g. cdc-42, nmy-1, and nmy-2. Based on these data, we suggest that male tail tip morphogenesis is governed by a gene regulatory network with a bow-tie architecture.

  15. Application of Bow-Tie Analysis in Hemp%BTA技术分析在HEMP中的应用

    Institute of Scientific and Technical Information of China (English)

    石天雄

    2010-01-01

    近年来,领结图分析(Bow-Tie Analysis,缩写BTA)技术日益广泛被应用于石油化工建设项目的HSE管理和安全设计中.作为技术核心,BTA对危害及后果管理程序(Hazards and Effects Management Process,缩写HEMP)的成败起到了至关重要的作用.在陈述BTA起源背景、理论方法的基础上,着重细化并解决了在石化项目HSE管理中与领结图中顶事件、威胁预防措施、应急削减措施和升级因素等关键要素相关联的事件和活动任务,给出了BTA在HEMP中的实施程序和应用举例,说明BTA是解决石化项目HSE管理和HEMP的工具.

  16. Compact self-grounded Bow-Tie antenna design for an UWB phased-array hyperthermia applicator.

    Science.gov (United States)

    Takook, Pegah; Persson, Mikael; Gellermann, Johanna; Trefná, Hana Dobšíček

    2017-01-08

    Using UWB hyperthermia systems has the potential to improve the heat delivery to deep seated tumours. In this paper, we present a novel self-grounded Bow-Tie antenna design which is to serve as the basis element in a phased-array applicator. The UWB operation in the frequency range of 0.43-1 GHz is achieved by immersing the antenna in a water bolus. The radiation characteristics are improved by appropriate shaping the water bolus and by inclusion of dielectric layers on the top of the radiating arms of the antenna. In order to find the most appropriate design, we use a combination of performance indicators representing the most important attributes of the antenna. These are the UWB impedance matching, the transmission capability and the effective field size. The antenna was constructed and experimentally validated on muscle-like phantom. The measured reflection and transmission coefficients as well as radiation characteristics are in excellent agreement with the simulated results. MR image acquisitions with antenna located inside MR bore indicate a negligible distortion of the images by the antenna itself, which indicates MR compatibility.

  17. The bow shock, cold fronts and disintegrating cool core in the merging galaxy group RXJ0751.3+5012

    CERN Document Server

    Russell, H R; McNamara, B R; Edge, A C; Sanders, J S; Nulsen, P E J; Baum, S A; Donahue, M; O'Dea, C P

    2014-01-01

    We present a new Chandra X-ray observation of the off-axis galaxy group merger RXJ0751.3+5012. The hot atmospheres of the two colliding groups appear highly distorted by the merger. The images reveal arc-like cold fronts around each group core, produced by the motion through the ambient medium, and the first detection of a group merger shock front. We detect a clear density and temperature jump associated with a bow shock of Mach number M=1.9+/-0.4 ahead of the northern group. Using galaxy redshifts and the shock velocity of 1100+/-300 km/s, we estimate that the merger axis is only 10deg from the plane of the sky. From the projected group separation of 90 kpc, this corresponds to a time since closest approach of 0.1 Gyr. The northern group hosts a dense, cool core with a ram pressure stripped tail of gas extending 100 kpc. The sheared sides of this tail appear distorted and broadened by Kelvin-Helmholtz instabilities. We use the presence of this substructure to place an upper limit on the magnetic field stren...

  18. Report on the Status of the Cheat Mountain Salamander in the Cabin Mountain Area of West Virginia 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This outlines the results of field surveys that were conducted for the Cheat Mountain salamander on the Kelley property on three mountains in the Cabin Mountain area...

  19. New models for Paleoproterozoic orogenesis in the Cheyenne belt region: Evidence from the geology and U-Pb geochronology of the Big Creek Gneiss, southeastern Wyoming

    Science.gov (United States)

    Jones, D.S.; Snoke, A.W.; Premo, W.R.; Chamberlain, K.R.

    2010-01-01

    The disputed age of the deep crust of the Colorado Province is central to hypotheses for Paleoproterozoic crustal growth in the region. We studied the high-grade Big Creek Gneiss, southeastern Wyoming, as a potential exposure of pre-1780 Ma basement rocks. New geologic mapping and U-Pb geochronological data indicate that the Big Creek Gneiss exposes a deeper, but coeval, level of the Green Mountain arc relative to the predominantly supracrustal section to the west. The Big Creek Gneiss is composed of: supracrustal rocks; a ca. 1780 Ma Green Mountain arc-correlative, bimodal intrusive suite; a ca. 1763 Ma extensional(?) bimodal intrusive suite; and widespread ca. 1630 Ma pegmatitic leucogranite. The mafic member of the younger bimodal suite is documented here for the first time. U-Pb zircon ages from migmatite leucosomes indicate penetrative deformation of the Big Creek Gneiss at ca. 1750 Ma. We find that the postarc intrusive suite is mantle-involved, implying a second period of crustal growth. Shortening postdates arc magmatism by ~20 m.y., implying that termination of arc magmatism and accretion were separate events. Finally, criteria previously used to constrain the polarity of subduction for the Green Mountain arc are not reliable. We propose two competing models: (1) southward-dipping Green Mountain arc subduction (present coordinates), with slab breakoff-related magmatism following arc accretion; or (2) northward-dipping subduction, with extensional postarc magmatism. In both models, high-temperature deformation coincides with accretion along the Cheyenne belt, and extensional magmatism is an important component of crustal growth. We prefer the northward-dipping subduction model because it can be better integrated with regional tectonic events and published isotopic compositions of the igneous rocks. ?? 2010 Geological Society of America.

  20. The mountain vegetation of South Peru

    NARCIS (Netherlands)

    Montesinos-Tubée, D.B.

    2016-01-01

    THE MOUNTAIN VEGETATION OF SOUTH PERU: SYNTAXONOMY, ECOLOGY, PHYTOGEOGRAPHY AND CONSERVATION This thesis presents an overview and revision of plant communities from xerophytic and mountain landscapes in the dry Andes of South Peru. The revision is based on comparison of the collecte