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Sample records for plasma region surrounding

  1. Earthquakes in Switzerland and surrounding regions during 2007

    Energy Technology Data Exchange (ETDEWEB)

    Baer, M.; Deichmann, N.; Clinton, J.; Husen, S.; Faeh, D.; Giardini, D.; Kaestli, P.; Kradolfer, U.; Wiemer, S

    2008-12-15

    This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2007. During this period, 531 earthquakes and 92 quarry blasts were detected and located in the region under consideration. Of these earthquakes, 30 are aftershocks of the stimulation of a proposed geothermal reservoir beneath the city of Basel in December of 2006. With 20 events with {mu}{sub {iota}} {>=} 2.5, four of which were artificially induced, the seismic activity in the year 2007 was far below the average over the previous 32 years. (author)

  2. Earthquakes in Switzerland and surrounding regions during 2007

    International Nuclear Information System (INIS)

    Baer, M.; Deichmann, N.; Clinton, J.; Husen, S.; Faeh, D.; Giardini, D.; Kaestli, P.; Kradolfer, U.; Wiemer, S.

    2008-01-01

    This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2007. During this period, 531 earthquakes and 92 quarry blasts were detected and located in the region under consideration. Of these earthquakes, 30 are aftershocks of the stimulation of a proposed geothermal reservoir beneath the city of Basel in December of 2006. With 20 events with Μ ι ≥ 2.5, four of which were artificially induced, the seismic activity in the year 2007 was far below the average over the previous 32 years. (author)

  3. Parameters of the luminous region surrounding deuterium pellets in the PLT tokamak

    International Nuclear Information System (INIS)

    McNeill, D.H.; Greene, G.J.; Schuresko, D.D.

    1985-08-01

    The luminous region of the plasma cloud surrounding deuterium pellets injected into a tokamak is studied spectroscopically. At the time of peak luminosity the average electron density is 2.4 x 10 17 cm -3 to within 30% and the temperature is at most 2.0 eV. The intensity ratio of the Balmer alpha and beta light from the pellets, the total number of emitted photons, and the apparent size of the radiating region are consistent with local thermodynamic equilibrium at this temperature and density

  4. Earthquakes in Switzerland and surrounding regions during 2006

    Energy Technology Data Exchange (ETDEWEB)

    Baer, M.; Deichmann, N.; Braunmiller, J.; Clinton, J.; Husen, S.; Faeh, D.; Giardini, D.; Kaestli, P.; Kradolfer, U.; Wiemer, S

    2007-12-15

    This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2006. During this period, 572 earthquakes and 91 quarry blasts were detected and located in the region under consideration. Of these earthquakes, two occurred in conjunction with the construction of the new Gotthard railway tunnel and 165 were induced artificially by the stimulation of a proposed geothermal reservoir beneath the city of Basel. With 20 events with {mu}{sub {iota}} {>=} 2.5, five of which were artificially induced, the seismic activity in the year 2006 was far below the average over the previous 31 years. Nevertheless, six events were felt by the public, most prominently the strongest of the induced Basel events ({mu}{sub {iota}} 3.4), which caused some non-structural building damage. Noteworthy are also the two earthquakes near Cortaillod ({mu}{sub {iota}} 3.2), on the shore of Lake Neuchatel, and in Val Mora ({mu}{sub {iota}} 3.5), between the Engadin and Val Muestair, as well as the 42 aftershocks of the {mu}{sub {iota}} 4.9 Vallorcine earthquake, between Martigny and Chamonix, of September 2005. (author)

  5. Earthquakes in Switzerland and surrounding regions during 2006

    International Nuclear Information System (INIS)

    Baer, M.; Deichmann, N.; Braunmiller, J.; Clinton, J.; Husen, S.; Faeh, D.; Giardini, D.; Kaestli, P.; Kradolfer, U.; Wiemer, S.

    2007-01-01

    This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2006. During this period, 572 earthquakes and 91 quarry blasts were detected and located in the region under consideration. Of these earthquakes, two occurred in conjunction with the construction of the new Gotthard railway tunnel and 165 were induced artificially by the stimulation of a proposed geothermal reservoir beneath the city of Basel. With 20 events with Μ ι ≥ 2.5, five of which were artificially induced, the seismic activity in the year 2006 was far below the average over the previous 31 years. Nevertheless, six events were felt by the public, most prominently the strongest of the induced Basel events (Μ ι 3.4), which caused some non-structural building damage. Noteworthy are also the two earthquakes near Cortaillod (Μ ι 3.2), on the shore of Lake Neuchatel, and in Val Mora (Μ ι 3.5), between the Engadin and Val Muestair, as well as the 42 aftershocks of the Μ ι 4.9 Vallorcine earthquake, between Martigny and Chamonix, of September 2005. (author)

  6. Plasma waves generated by rippled magnetically focused electron beams surrounded by tenuous plasmas

    International Nuclear Information System (INIS)

    Cuperman, S.; Petran, F.

    1982-01-01

    This chapter investigates the electrostatic instability and the corresponding unstable wave spectrum of magnetically focused neutralized rippled electron beams under spacelike conditions. Topics considered include general equations and equilibrium, the derivation of the dispersion relation, and the solution of the dispersion relation (long wavelength perturbations, short wavelength perturbations, the rippled beam). The results indicate that in the long wavelength limit two types of instability (extending over different frequency ranges) exist. An instability of the beam-plasma type occurs due to the interaction between the beam electrons and the surrounding plasm electrons at the beam-plasma interface. A parametric type instability is produced by the coupling of a fast forward wave and a fast backward wave due to the rippling (modulation) of the beam. It is demonstrated that in the short wavelength limit, surface waves which are stable for the laminar beam may become unstable in the rippled beam case

  7. Hurricane Dennis Aerial Photography: Draft Image Mosaics of the Florida Panhandle and Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the Florida panhandle and surrounding regions after Hurricane Dennis made landfall. The regions photographed range from...

  8. Hurricane Humberto Aerial Photography: Rapid Response Imagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regions after Hurricane Humberto made landfall. The aerial photography missions were conducted by the NOAA...

  9. Tropical Storm Ernesto Aerial Photography: Rapid Response Imagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regions after Tropical Storm Ernesto made landfall. The aerial photography missions were conducted by the NOAA...

  10. Control of radial propagation and polarity in a plasma jet in surrounding Ar

    KAUST Repository

    Gong, W.

    2018-01-08

    In recent years, the use of shielding gas to prevent the diffusion of the ambient air, particularly oxygen and nitrogen species, into the effluent of the atmospheric pressure plasma jet, and thus control the nature of chemical species used in the plasma treatment has increased. In this paper, the radial propagation of a plasma jet in ambient Ar is examined to find the key determinants of the polarity of plasma jets. The dynamics of the discharge reveal that the radial diffusion discharge is a special phenomenon observed only at the falling edge of the pulses. The radial transport of electrons, which is driven by the radial component of the applied electric field at the falling edge of the pulse, is shown to play an important role in increasing the seed electron density in the surrounding Ar. This result suggests a method to provide seed electrons at atmospheric pressure with a negative discharge. The polarity of the plasma jet is found to be determined by the pulse width rather than the polarity of the applied voltage, as it dictates the relative difference in the intensity of the two discharges in a single pulse, where the stronger discharge in a pulse dominates the behavior of the plasma jet. Accordingly, a method to control the polarity of a plasma jet through varying the pulse width is developed. Since plasma jets of different polarities differ remarkably in terms of their characteristics, the method to control the polarity reported in this paper will be of use for such applications as plasma-enhanced processing of materials and plasma biomedicine.

  11. Control of radial propagation and polarity in a plasma jet in surrounding Ar

    Science.gov (United States)

    Gong, W.; Yue, Y.; Ma, F.; Yu, F.; Wan, J.; Nie, L.; Bazaka, K.; Xian, Y.; Lu, X.; Ostrikov, K.

    2018-01-01

    In recent years, the use of shielding gas to prevent the diffusion of the ambient air, particularly oxygen and nitrogen species, into the effluent of the atmospheric pressure plasma jet, and thus control the nature of chemical species used in the plasma treatment has increased. In this paper, the radial propagation of a plasma jet in ambient Ar is examined to find the key determinants of the polarity of plasma jets. The dynamics of the discharge reveal that the radial diffusion discharge is a special phenomenon observed only at the falling edge of the pulses. The radial transport of electrons, which is driven by the radial component of the applied electric field at the falling edge of the pulse, is shown to play an important role in increasing the seed electron density in the surrounding Ar. This result suggests a method to provide seed electrons at atmospheric pressure with a negative discharge. The polarity of the plasma jet is found to be determined by the pulse width rather than the polarity of the applied voltage, as it dictates the relative difference in the intensity of the two discharges in a single pulse, where the stronger discharge in a pulse dominates the behavior of the plasma jet. Accordingly, a method to control the polarity of a plasma jet through varying the pulse width is developed. Since plasma jets of different polarities differ remarkably in terms of their characteristics, the method to control the polarity reported in this paper will be of use for such applications as plasma-enhanced processing of materials and plasma biomedicine.

  12. A matching approach to communicate through the plasma sheath surrounding a hypersonic vehicle

    International Nuclear Information System (INIS)

    Gao, Xiaotian; Jiang, Binhao

    2015-01-01

    In order to overcome the communication blackout problem suffered by hypersonic vehicles, a matching approach has been proposed for the first time in this paper. It utilizes a double-positive (DPS) material layer surrounding a hypersonic vehicle antenna to match with the plasma sheath enclosing the vehicle. Analytical analysis and numerical results indicate a resonance between the matched layer and the plasma sheath will be formed to mitigate the blackout problem in some conditions. The calculated results present a perfect radiated performance of the antenna, when the match is exactly built between these two layers. The effects of the parameters of the plasma sheath have been researched by numerical methods. Based on these results, the proposed approach is easier to realize and more flexible to the varying radiated conditions in hypersonic flight comparing with other methods

  13. Radiation pattern of open ended waveguide in air core surrounded by annular plasma column

    International Nuclear Information System (INIS)

    Sharma, D.R.; Verma, J.S.

    1977-01-01

    Radiation pattern of open ended waveguide excited in circular symmetric mode (TM 01 ) in an air core having central conductor and surrounded by an annular plasma column is studied. The field distribution at the open end of the waveguide is considered to be equivalent to the vector sum of magnetic current rings of various radii, ranging from the outer radius of the inner conductor to the inner radius of the outer conductor of the waveguide at the open end. The radiation field is obtained as a vector sum of field components due to individual rings of current. Such a configuration gives rise to multiple narrow radiation beams away from the critical angle. (author)

  14. High-Resolution Regional Phase Attenuation Models of the Iranian Plateau and Surrounding Regions

    Science.gov (United States)

    2014-03-03

    crustal structure or sediment thickness across much of the Iranian plateau. The lone exception is the region between the central Zagros and the Lut block...L11303, 2007. Meunier, P., N. Hovius, and J. A. Haines, Topographic site effects and the location of earthquake induced landslides, Earth Planet . Sci

  15. Hurricane Ivan Aerial Photography: High-Resolution Imagery of the Florida Panhandle and Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the Florida panhandle and surrounding regions after Hurricane Ivan made landfall. The regions photographed range from Gulf...

  16. Crustal structure beneath Beijing and its surrounding regions derived from gravity data

    Science.gov (United States)

    Jiang, Wenliang; Zhang, Jingfa; Lu, Xiaocui; Lu, Jing

    2011-06-01

    In this paper we use gravity data to study fine crustal structure and seismogenic environment beneath Beijing and its surrounding regions. Multi-scale wavelet analysis method is applied to separating gravity fields. Logarithmic power spectrum method is also used to calculate depth of gravity field source. The results show that the crustal structure is very complicated beneath Beijing and its surrounding areas. The crustal density exhibits laterally inhomogeneous. There are three large scale tectonic zones in North China, i.e., WNW-striking Zhangjiakou-Bohai tectonic zone (ZBTZ), NE-striking Taihang piedmont tectonic zone (TPTZ) and Cangxian tectonic zone (CTZ). ZBTZ and TPTZ intersect with each other beneath Beijing area and both of them cut through the lithosphere. The upper and middle crusts consist of many small-scale faults, uplifts and depressions. In the lower crust, these small-scale tectonic units disappear gradually, and they are replaced by large-scale tectonic units. In surrounding regions of Beijing, ZBTZ intersects with several other NE-striking tectonic units, such as Cangxian uplift, Jizhong depression and Shanxi Graben System (SGS). In west of Taihangshan uplift, gravity anomalies in upper and middle crusts are correlated with geological and topographic features on the surface. Compared with the crust, the structure is comparatively simple in uppermost mantle. Earthquakes mainly occurred in upper and middle crusts, especially in transitional regions between high gravity anomaly and low gravity anomaly. Occurrence of large earthquakes may be related to the upwelling of upper mantle and asthenosphere heat flow materials, such as Sanhe earthquake ( M S8.0) and Tangshan earthquake ( M S7.8).

  17. Urban land use in Natura 2000 surrounding areas in Vilnius Region, Lithuania.

    Science.gov (United States)

    Pereira, Paulo; Misiūnė, Ieva; Depellegrin, Daniel

    2015-04-01

    Urban development is one of the major causes of land degradation and pressure on protected areas. (Hansen and DeFries, 2007; Salvati and Sabbi, 2011). The urban areas in the fringe of the protected areas are a source of pollutants considered a negative disturbance to the ecosystems services and biodiversity within the protected areas. The distance between urban and protected areas is decreasing and in the future it is estimated that 88% of the world protected areas will be affected by urban growth (McDonald et al., 2008). The surrounding or buffer areas, are lands adjacent to the Natura 2000 territories, which aim to reduce the human influence within the protected areas. Presently there is no common definition of buffer area it is not clear among stakeholders (Van Dasselaar, 2013). The objective of this work is to identify the urban land use in the Natura 2000 areas in Vilnius region, Lithuania. Data from Natura 2000 areas and urban land use (Corine Land Cover 2006) in Vilnius region were collected in the European Environmental Agency website (http://www.eea.europa.eu/). In the surroundings of each Natura 2000 site, we identified the urban land use at the distances of 500, 1000 and 1500 m. The Natura 2000 sites and the urban areas occupied a total of 13.2% and 3.4% of Vilnius region, respectively. However, the urban areas are very dispersed in the territory, especially in the surroundings of Vilnius, which since the end of the XX century is growing (Pereira et al., 2014). This can represent a major threat to Natura 2000 areas ecosystem services quality and biodiversity. Overall, urban areas occupied approximately 50 km2, in the buffer area of 500 m, 95 km2 in buffer area of 1000 m and 131 km2 in the buffer area of 1500 km2. This shows that Natura 2000 surrounding areas in Vilnius region are subjected to a high urban pressure. This is especially evident in the Vilnius city and is a consequence of the uncontrolled urban development. The lack of a clear legislation

  18. Three-dimensional lithospheric density distribution of China and surrounding regions

    Directory of Open Access Journals (Sweden)

    Chuantao Li

    2014-01-01

    Full Text Available In this paper, we analyze lithospheric density distribution of China and surrounding regions on the basis of 30′ × 30′ gravity data and 1° × 1° P-wave velocity data. Firstly, we used the empirical equation between the density and the P-wave velocity difference as the base of the initial model of the Asian lithospheric density. Secondly, we calculated the gravity anomaly, caused by the Moho discontinuity and the sedimentary layer discontinuity, by the Parker formula. Thirdly, the gravity anomaly of the spherical harmonics with 2–40 order for the anomalous body below the lithosphere is calculated based on the model of EGM96. Finally, by using Algebra Reconstruction Techniques (ART, the inversion of 30′ × 30′ residual lithospheric Bouguer gravity anomaly caused by the lithosphere yields a rather detailed structural model. The results show that the lithospheric density distribution of China and surrounding regions has a certain connection with the tectonic structure. The density is relatively high in the Philippine Sea plate, Japan Sea, the Indian plate, the Kazakhstan shield and the Western Siberia plain, whereas the Tibetan Plateau has low-density characteristics. The minimum value of density lies in the north of Philippines, in the Taiwan province and in the Ryukyu island arc.

  19. Natural Radioactivity in Abu-Tartor Phosphate Deposits and the Surrounding Region, New Valley, Egypt

    International Nuclear Information System (INIS)

    Khater, A.E.; Higgy, R.H.; Pimpl, M.

    1999-01-01

    Abu-Tartor phosphate mine. New Valley district, is one of the biggest phosphate mines in Egypt which will start full production soon. The planned ore rocks (24.8%P 2 O 5 ) annual production is 4 million tons. The aim of this study is to estimate the natural radioactivity levels in Abu-Tartor phosphate deposits and the surrounding region. The environmental radioactivity levels in the surrounding region will be considered as pre-operational levels which are essential to determine the radiological impacts of phosphate mining later on. Phosphate samples (ore rocks, wet rocks and beneficiation wastes) and environmental samples (soil, water and plant)were collected. The specific activities of Ra-226 (U-238) series, Th-232 series and K-40 were measured using gamma-ray spectrometry based on Hyper pure Germanium detectors. The specific activities of uranium isotopes (U-238, U-235 and U-234) were measured using alpha spectrometry based on surface barrier detectors after radiochemical separation. The specific activity of Pb-210 was measured using low background proportional gas counting system after radiochemical separation . The results were discussed and compared with national and international values

  20. Conserving Prairie Pothole Region wetlands and surrounding grasslands: evaluating effects on amphibians

    Science.gov (United States)

    Mushet, David M.; Neau, Jordan L.

    2014-01-01

    The maintenance of viable and genetically diverse populations of amphibians in the Prairie Pothole Region of the United States depends on upland as well as wetland over-wintering and landscape level habitat features.Prairie pothole wetlands provide important amphibian breeding habitat while grasslands surrounding these wetlands provide foraging habitat for adults, overwintering habitat for some species, and important connectivity among breeding wetlands.Grasslands surrounding wetlands were found to be especially important for wood frogs and northern leopard frogs, while croplands dominated habitat utilized by Great Plains toads and Woodhouse’s toads.Habitat suitability mapping highlighted (1) the influence of deep-water overwintering wetlands on suitable habitat for four of five anuran species encountered; (2) the lack of overlap between areas of core habitat for both the northern leopard frog and wood frog compared to the core habitat for both toad species; and (3) the importance of conservation programs in providing grassland components of northern leopard frog and wood frog habitat.Currently, there are approximately 7.2 million acres (2.9 million hectares, ha) of habitat in the PPR identified as suitable for amphibians. WRP and CRP wetland and grassland habitats accounted for approximately 1.9 million acres (0.75 million ha) or 26 percent of this total area.Continued loss of amphibian habitat resulting from an ongoing trend of returning PPR conservation lands to crop production, will likely have significant negative effects on the region’s ability to maintain amphibian biodiversity. Conversely, increases in conservation wetlands and surrounding grasslands on the PPR landscape have great potential to positively influence the region’s amphibian populations.

  1. Plasma surrounding the global heliosphere at large distances controlled by the solar cycle

    Science.gov (United States)

    Dialynas, Konstantinos; Krimigis, Stamatios; Mitchell, Donald; Decker, Robert; Roelof, Edmond

    2016-04-01

    The past decade can be characterized by a series of key, groundbreaking remote energetic neutral atom (ENA) images (INCA, IBEX) and in-situ ion (Voyager 1 & 2) observations concerning the characteristics and interactions of the heliosphere with the Local Interstellar Medium (LISM). Voyagers 1 and 2 (V1, V2) discovered the reservoir of ions and electrons that constitute the heliosheath (HS) after crossing the termination shock (TS) 35deg north and 32deg south of the ecliptic plane at 94 and 84 astronomical units (1 AU= 1.5 x108 km), respectively. The in situ measurements by each Voyager were placed in a global context by remote sensing images using ENA obtained with the Ion and Neutral Camera (INCA) onboard Cassini orbiting Saturn. The ENA images contain a 5.2-55 keV hydrogen (H) ENA region (Belt) that loops through the celestial sphere and contributes to balancing the pressure of the interstellar magnetic field (ISMF). The success of any future mission with dedicated ENA detectors (e.g. the IMAP mission), highly depends on the antecedent understanding of the details of the plasma processes in the Heliosphere as revealed by remote sensing of the plasma environment characteristics. Therefore, we address here one of the remaining and most important questions: "Where do the 5-55 keV ENAs that INCA measures come from?". We analyzed INCA all-sky maps from 2003 to 2015 and compare the solar cycle (SC) variation of the ENAs in both the nose (upstream) and anti-nose (downstream) directions with the intensities of > 30 keV ions (source of ENA through charge exchange-CE with H) measured in-situ by V1 and V2, in overlapping energy bands ~30-55 keV. ENA intensities decrease during the declining phase of SC23 by ~x3 from 2003 to 2011 but recover through 2014 (SC24); similarly, V1 and V2 ion intensities also decrease and then recover through 2014. The similarity of time profiles of remotely sensed ENA and locally measured ions are consistent with (a) ENA originating in the HS

  2. Lithospheric flexural strength and effective elastic thicknesses of the Eastern Anatolia (Turkey) and surrounding region

    Science.gov (United States)

    Oruç, Bülent; Gomez-Ortiz, David; Petit, Carole

    2017-12-01

    The Lithospheric structure of Eastern Anatolia and the surrounding region, including the northern part of the Arabian platform is investigated via the analysis and modeling of Bouguer anomalies from the Earth Gravitational Model EGM08. The effective elastic thickness of the lithosphere (EET) that corresponds to the mechanical cores of the crust and lithospheric mantle is determined from the spectral coherence between Bouguer anomalies and surface elevation data. Its average value is 18.7 km. From the logarithmic amplitude spectra of Bouguer anomalies, average depths of the lithosphere-asthenosphere boundary (LAB), Moho, Conrad and basement in the study area are constrained at 84 km, 39 km, 16 km and 7 km, respectively. The geometries of the LAB and Moho are then estimated using the Parker-Oldenburg inversion algorithm. We also present a lithospheric strength map obtained from the spatial variations of EET determined by Yield Stress Envelopes (YSE). The EET varies in the range of 12-23 km, which is in good agreement with the average value obtained from spectral analysis. Low EET values are interpreted as resulting from thermal and flexural lithospheric weakening. According to the lithospheric strength of the Eastern Anatolian region, the rheology model consists of a strong but brittle upper crust, a weak and ductile lower crust, and a weak lower part of the lithosphere. On the other hand, lithosphere strength corresponds to weak and ductile lower crust, a strong upper crust and a strong uppermost lithospheric mantle for the northern part of the Arabian platform.

  3. New gravity anomaly map of Taiwan and its surrounding regions with some tectonic interpretations

    Science.gov (United States)

    Doo, Wen-Bin; Lo, Chung-Liang; Hsu, Shu-Kun; Tsai, Ching-Hui; Huang, Yin-Sheng; Wang, Hsueh-Fen; Chiu, Shye-Donq; Ma, Yu-Fang; Liang, Chin-Wei

    2018-04-01

    In this study, we compiled recently collected (from 2005 to 2015) and previously reported (published and open access) gravity data, including land, shipborne and satellite-derived data, for Taiwan and its surrounding regions. Based on the cross-over error analysis, all data were adjusted; and, new Free-air gravity anomalies were obtained, shedding light on the tectonics of the region. To obtain the Bouguer gravity anomalies, the densities of land terrain and marine sediments were assumed to be 2.53 and 1.80 g/cm3, respectively. The updated gravity dataset was gridded with a spacing of one arc-minute. Several previously unnoticed gravity features are revealed by the new maps and can be used in a broad range of applications: (1) An isolated gravity high is located between the Shoushan and the Kaoping Canyon off southwest Taiwan. (2) Along the Luzon Arc, both Free-air and Bouguer gravity anomaly maps reveal a significant gravity discontinuity feature at the latitude of 21°20‧N. (3) In the southwestern Okinawa Trough, the NE-SW trending cross-back-arc volcanic trail (CBVT) marks the low-high gravity anomaly (both Free-air and Bouguer) boundary.

  4. A computer hydrogeologic model of the Nevada Test Site and surrounding region

    International Nuclear Information System (INIS)

    Gillson, R.; Hand, J.; Adams, P.; Lawrence, S.

    1996-01-01

    A three-dimensional, hydrogeologic model of the Nevada Test Site and surrounding region was developed as an element for regional groundwater flow and radionuclide transport models. The hydrogeologic model shows the distribution, thickness, and structural relationships of major aquifers and confining units, as conceived by a team of experts organized by the U.S. Department of Energy Nevada Operations Office. The model was created using Intergraph Corporation's Geographical Information System based Environmental Resource Management Application software. The study area encompasses more than 28,000 square kilometers in southern Nevada and Inyo County, California. Fifty-three geologic cross sections were constructed throughout the study area to provide a framework for the model. The lithology was simplified to 16 hydrostratigraphic units, and the geologic structures with minimal effect on groundwater flow were removed. Digitized cross sections, surface geology, and surface elevation data were the primary sources for the hydrogeologic model and database. Elevation data for the hydrostratigraphic units were posted, contoured, and gridded. Intergraph Corporation's three-dimensional visualization software, VOXEL trademark, was used to view the results interactively. The hydrogeologic database will be used in future flow modeling activities

  5. Control of radial propagation and polarity in a plasma jet in surrounding Ar

    KAUST Repository

    Gong, W.; Yue, Y.; Ma, F.; Yu, F.; Wan, J.; Nie, L.; Bazaka, K.; Xian, Y.; Lu, X.; Ostrikov, K.

    2018-01-01

    In recent years, the use of shielding gas to prevent the diffusion of the ambient air, particularly oxygen and nitrogen species, into the effluent of the atmospheric pressure plasma jet, and thus control the nature of chemical species used

  6. Effect of power-plant waste on farming in the surrounding regions

    Energy Technology Data Exchange (ETDEWEB)

    Kozel, J; Maly, V

    1972-01-01

    The results of research undertaken concerning the waste of two power plants in Czechoslovakia are presented. Increased dust was observed in the proximity of the waste as compared with distant sites. Some dirt was observed in the crops around the waste - this demonstrates the dust infestation of the crops. The content of ash in the organic dry matter in farm crops in the proximity of waste were also higher than in the same crops in unaffected regions. Sulfur compounds were found in the ash of organic matter and in its dry matter that exceed the normal values. Dust blocked the pores of the assimilation organs of crops, although the value was lower than in forest wood species, particularly conifers. In most cases the analyses of soil samples collected around the waste demonstrated an increase in lime content. The soils around the wastes were found to contain sulfates, in some cases in fairly high amounts. Spectral analysis revealed trace amounts of some microelements which might have a toxic effect if their contents were increased (As, Pb, Zn, Cr, Be, Ni, Co). The fly ash had a negative influence on the physical properties of soil in the surrounding fields. In the vicinity of the waste severe dampness of the fields was observed in some cases. The dampness of soil decreased with the distance from the waste although moisture values characteristic of soil dampness were found 400 meters from the waste.

  7. Hurricane Gustav Aerial Photography: Rapid ResponseImagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regionsafter Hurricane Gustav made landfall. The aerial photography missions wereconducted by the NOAA Remote...

  8. Hurricane Ike Aerial Photography: Rapid ResponseImagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regionsafter Hurricane Ike made landfall. The aerial photography missions wereconducted by the NOAA Remote...

  9. Influence of surrounding gas, composition and pressure on plasma plume dynamics of nanosecond pulsed laser-induced aluminum plasmas

    Directory of Open Access Journals (Sweden)

    Mahmoud S. Dawood

    2015-10-01

    Full Text Available In this article, we present a comprehensive study of the plume dynamics of plasmas generated by laser ablation of an aluminum target. The effect of both ambient gas composition (helium, nitrogen or argon and pressure (from ∼5 × 10−7 Torr up to atmosphere is studied. The time- and space- resolved observation of the plasma plume are performed from spectrally integrated images using an intensified Charge Coupled Device (iCCD camera. The iCCD images show that the ambient gas does not significantly influence the plume as long as the gas pressure is lower than 20 Torr and the time delay below 300 ns. However, for pressures higher than 20 Torr, the effect of the ambient gas becomes important, the shortest plasma plume length being observed when the gas mass species is highest. On the other hand, space- and time- resolved emission spectroscopy of aluminum ions at λ = 281.6 nm are used to determine the Time-Of-Flight (TOF profiles. The effect of the ambient gas on the TOF profiles and therefore on the propagation velocity of Al ions is discussed. A correlation between the plasma plume expansion velocity deduced from the iCCD images and that estimated from the TOF profiles is presented. The observed differences are attributed mainly to the different physical mechanisms governing the two diagnostic techniques.

  10. Downshift of electron plasma oscillations in the electron foreshock region

    International Nuclear Information System (INIS)

    Fuselier, S.A.; Gurnett, D.A.; Fitzenreiter, R.J.; NASA, Goddard Space Flight Center, Greenbelt, MD)

    1985-01-01

    Electron plasma oscillations in the earth's electron foreshock region are observed to shift above and below the local electron plasma frequency. As plasma oscillations shift downward from the plasma frequency, their bandwidth increases and their wavelength decreases. Observations of plasma oscillations well below the plasma frequency are correlated with times when ISEE 1 is far downstream of the electron foreshock boundary. Although wavelengths of plasma oscillations below the plasma frequency satisfy k x lambda-De approximately 1 the Doppler shift due to the motion of the solar wind is not sufficient to produce the observed frequency shifts. A beam-plasma interaction with beam velocities on the order of the electron thermal velocity is suggested as an explanation for plasma oscillations above and below the plasma frequency. Frequency, bandwidth, and wavelength changes predicted from the beam-plasma interaction are in good agreement with the observed characteristics of plasma oscillations in the foreshock region. 28 references

  11. Downshift of electron plasma oscillations in the electron foreshock region

    International Nuclear Information System (INIS)

    Fuselier, S.A.

    1984-01-01

    Electron plasma oscillations in the Earth's electron foreshock region are observed to shift above and below the local electron plasma frequency. As plasma oscillations shift from the plasma frequency, their bandwidth increases and their wavelength decreases. Observations of plasma oscillations well below the plasma frequency are correlated with times when ISEE-I is far downstream of the electron foreshock boundary. Although wavelengths of plasma oscillations below the plasma frequency satisfy klambda/sub De/ approx. = 1, the Doppler shift due to the motion of the solar wind is not sufficient to produce the observed frequency shifts. A beam-plasma interaction with beam velocities on the order of the electron thermal velocity is suggested as an explanation for plasma oscillations above and below the plasma frequency. Frequency, bandwidth, and wavelength changes predicted from the beam-plasma interaction are in good agreement with the observed characteristics of plasma oscillations in the foreshock region

  12. Estimating the size of the cavity and surrounding failed region for underground nuclear explosions from scaling rules

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Leo A [El Paso Natural Gas Company (United States)

    1970-05-01

    The fundamental physical principles involved in the formation of an underground cavity by a nuclear explosion and breakage of the rock surrounding the cavity are examined from the point of view of making preliminary estimates of their sizes where there is a limited understanding of the rock characteristics. Scaling equations for cavity formation based on adiabatic expansion are reviewed and further developed to include the strength of the material surrounding the shot point as well as the overburden above the shot point. The region of rock breakage or permanent distortion surround ing the explosion generated cavity is estimated using both the Von Mises and Coulomb-Mohr failure criteria. It is found that the ratio of the rock failure radius to the cavity radius for these two criteria becomes independent of yield and dependent only on the failure mechanics of the rock. The analytical solutions developed for the Coulomb-Mohr and Von Mises criteria are presented in graphical form. (author)

  13. Economic impact of accelerated cleanup on regions surrounding the US DOE's major nuclear weapons sites

    International Nuclear Information System (INIS)

    Greenberg, M.; Solitare, L.; Frisch, M.; Lowrie, K.

    1999-01-01

    The regional economic impacts of the US Department of Energy's accelerated environmental cleanup plan are estimated for the major nuclear weapons sites in Colorado, Idaho, New Mexico, South Carolina, Tennessee, and Washington. The analysis shows that the impact falls heavily on the three relatively rural regions around the Savannah River (SC), Hanford (WA), and Idaho National Engineering and Environmental Laboratory (ID) sites. A less aggressive phase-down of environmental management funds and separate funds to invest in education and infrastructure in the regions helps buffer the impacts on jobs, personal income, and gross regional product. Policy options open to the federal and state and local governments are discussed

  14. Optical and infrared study of the region surrounding Herbig-Haro objects 1 and 2

    International Nuclear Information System (INIS)

    Strom, S.E.; Strom, K.M.; Grasdalen, G.L.; Sellgren, K.; Wolff, S.; Wyoming Univ., Laramie; Hawaii Univ., Honolulu)

    1985-01-01

    Optical and near-IR observations of the environs of H-H objects 1 and 2 provide the basis for identifying a recently discovered radio continuum as the star responsible for powering the highly collimated mass outflow traced by these objects. Polarimetric observations show that the source (designated as VLA 1), located at the midpoint between HH 1 and 2, illuminates a biconical reflection nebula. It is suggested that VLA 1 is probably surrounded by an optically thick disk viewed edge on; an optical jet emanates from the vicinity of HH 1 and is directed along the axis of the putative disk toward HH 1; its spectrum resembles that of HH 1 and other Herbig-Haro objects. 37 references

  15. Wind field measurement in the nonprecipitous regions surrounding storms by an airborne pulsed Doppler lidar system, appendix A

    Science.gov (United States)

    Bilbro, J. W.; Vaughan, W. W.

    1980-01-01

    Coherent Doppler lidar appears to hold great promise in contributing to the basic store of knowledge concerning flow field characteristics in the nonprecipitous regions surrounding severe storms. The Doppler lidar, through its ability to measure clear air returns, augments the conventional Doppler radar system, which is most useful in the precipitous regions of the storm. A brief description of the Doppler lidar severe storm measurement system is provided along with the technique to be used in performing the flow field measurements. The application of the lidar is addressed, and the planned measurement program is outlined.

  16. A regional study of the radiation environment of Greenham Common, Newbury District and surrounding areas

    International Nuclear Information System (INIS)

    1997-02-01

    This study was commissioned by Newbury District Council and Basingstoke and Deane Borough Council in response to public concern following disclosures about events at Greenham Common in the 1950s, and the suspicion that there may have been an accident involving a nuclear weapon leading to off-site contamination at the airbase. The Greenham Common airbase is at an advanced stage of decommissioning with parts of the site already re-developed for industrial and leisure purposes and material being removed for use in construction of the Newbury by-pass. The success of such developments is critically dependent on public confidence in the quality of the environment, both near the site, and more generally throughout the area. For this reason the study was commissioned with the aims of: I. defining the radiation environment of the whole district and parts of its surrounding areas. II. examining whether there is any evidence of radioactive contamination in the vicinity of the Greenham Common airbase. III. assessing the evidence that there may have been a release of nuclear material from the site. The work involved a collaboration between scientists from the Scottish Universities Research and Reactor Centre, who conducted gamma ray surveys to define the general radiation environment of the area, and Scientists from the University of Southampton who collected an extensive range of samples for high sensitivity radiochemical analyses. This report presents their findings and main conclusions, together with a discussion of the background to the study and its implications. (Author)

  17. Plasma composition in a sigmoidal anemone active region

    International Nuclear Information System (INIS)

    Baker, D.; Van Driel-Gesztelyi, L.; Green, L. M.; Carlyle, J.; Brooks, D. H.; Démoulin, P.; Steed, K.

    2013-01-01

    Using spectra obtained by the EUV Imaging Spectrometer (EIS) instrument onboard Hinode, we present a detailed spatially resolved abundance map of an active region (AR)-coronal hole (CH) complex that covers an area of 359'' × 485''. The abundance map provides first ionization potential (FIP) bias levels in various coronal structures within the large EIS field of view. Overall, FIP bias in the small, relatively young AR is 2-3. This modest FIP bias is a consequence of the age of the AR, its weak heating, and its partial reconnection with the surrounding CH. Plasma with a coronal composition is concentrated at AR loop footpoints, close to where fractionation is believed to take place in the chromosphere. In the AR, we found a moderate positive correlation of FIP bias with nonthermal velocity and magnetic flux density, both of which are also strongest at the AR loop footpoints. Pathways of slightly enhanced FIP bias are traced along some of the loops connecting opposite polarities within the AR. We interpret the traces of enhanced FIP bias along these loops to be the beginning of fractionated plasma mixing in the loops. Low FIP bias in a sigmoidal channel above the AR's main polarity inversion line, where ongoing flux cancellation is taking place, provides new evidence of a bald patch magnetic topology of a sigmoid/flux rope configuration.

  18. Diversity of microorganisms isolated from the soil sample surround Chroogomphus rutilus in the Beijing region

    DEFF Research Database (Denmark)

    Wang, P; Liu, Y; Yin, Y

    2011-01-01

    to isolate and classify beneficial microorganisms that could affect its growth, which could be used in future research on artificial cultivation. In total, 342 isolates were isolated from soil samples collected around a C. rutilus colony in the Beijing region. Of these, 22 bacterial and 14 fungal isolates...

  19. Stochastic analysis of uncertain thermal characteristic of foundation soils surrounding the crude oil pipeline in permafrost regions

    International Nuclear Information System (INIS)

    Wang, Tao; Zhou, Guoqing; Wang, Jianzhou; Zhao, Xiaodong

    2016-01-01

    Highlights: • The influence of stochastic properties and conditions on permafrost foundation was investigated. • A stochastic analysis for the uncertain thermal characteristic of crude oil pipe is presented. • The mean temperature and standard deviation of foundation soils are obtained and analyzed. • Average standard deviation and maximum standard deviation of foundation soils increase with time. - Abstract: For foundation soils surrounding the crude oil pipeline in permafrost regions, the soil properties and the upper boundary conditions are stochastic because of complex geological processes and changeable atmospheric environment. The conventional finite element analysis of thermal characteristics for crude oil pipeline is always deterministic, rather than taking stochastic parameters and conditions into account. This study investigated the stochastic influence of an underground crude oil pipeline on the thermal stability of the permafrost foundation on the basis of a stochastic analysis model and the stochastic finite element method. A stochastic finite element program is compiled by Matrix Laboratory (MATLAB) software, and the random temperature fields of foundation soils surrounding a crude oil pipeline in a permafrost region are obtained and analyzed by Neumann stochastic finite element method (NSFEM). The results provide a new way to predict the thermal effects of the crude oil pipeline in permafrost regions, and it shows that the standard deviations in temperature increase with time when considering the stochastic effect of soil properties and boundary conditions, which imply that the results of conventional deterministic analysis may be far from the true value, even if in different seasons. It can improve our understanding of the random temperature field of foundation soils surrounding the crude oil pipeline and provide a theoretical basis for actual engineering design in permafrost regions.

  20. A regional water balance for the WIPP site and surrounding area

    International Nuclear Information System (INIS)

    Hunter, R.L.

    1987-01-01

    A water balance or budget is developed as an accounting of the components of a closed hydrologic system. In the WIPP study area, water-budget techniques have previously been used to compute leakage from Lake Avalon and from potash refinery spoil ponds. A general expression for a closed hydrologic system is presented. In a developed area like the WIPP region, the water budget must include many usage factors, such as municipal or industrial pumpage. In the WIPP water-budget study area, inflows are precipitation, surface- and ground-water inflow, and the artificial addition of surface and ground water. Outflows are surface runoff, evaporation and transpiration, and ground-water outflow. Changes in storage in the WIPP region have also been documented. The WIPP water balance described here is based on a combination of long-term averages and figures for 1980. 12 refs., 5 figs., 1 tab

  1. Wetted-region structure in horizontal unsaturated fractures: Water entry through the surrounding porous matrix

    International Nuclear Information System (INIS)

    Glass, R.J.; Norton, D.L.

    1991-01-01

    Small-scale processes that influence wetted structure within the plane of a horizontal fracture as the fracture wets or drains through the matrix are investigated. Our approach integrates both aperture-scale modeling and physical experimentation. Several types of aperture-scale models have been defined and implemented. A series of physical experimental systems that allow us to measure wetted-region structure as a function of system parameters and water pressure head in analogue fractures also have been designed. In our preliminary proof-of-concept experiment, hysteresis is clearly evident in the measured saturation/pressure relation, as is the process of air entrapment, which causes a reduction in the connected areas between blocks and the wetted region available for flow in the plane of the fracture. A percolation threshold where the system is quickly spanned, allowing fluid conduction in the fracture plane, is observed which is analogous to that found in the aperture-scale models. A fractal wetted and entrapped-region structure is suggested by both experiment and modeling. This structure implies that flow tortuosity for both flow in the fracture and for inter-block fluid transfer is a scale-dependent function of pressure head

  2. Formation of secondary organic aerosol in the Paris pollution plume and its impact on surrounding regions

    Science.gov (United States)

    Zhang, Q. J.; Beekmann, M.; Freney, E.; Sellegri, K.; Pichon, J. M.; Schwarzenboeck, A.; Colomb, A.; Bourrianne, T.; Michoud, V.; Borbon, A.

    2015-12-01

    Secondary pollutants such as ozone, secondary inorganic aerosol, and secondary organic aerosol formed in the plumes of megacities can affect regional air quality. In the framework of the FP7/EU MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) project, an intensive campaign was launched in the greater Paris region in July 2009. The major objective was to quantify different sources of organic aerosol (OA) within a megacity and in its plume. In this study, we use airborne measurements aboard the French ATR-42 aircraft to evaluate the regional chemistry-transport model CHIMERE within and downwind of the Paris region. Two mechanisms of secondary OA (SOA) formation are used, both including SOA formation from oxidation and chemical aging of primary semivolatile and intermediate volatility organic compounds (SI-SOA) in the volatility basis set (VBS) framework. As for SOA formed from traditional VOC (volatile organic compound) precursors (traditional SOA), one applies chemical aging in the VBS framework adopting different SOA yields for high- and low-NOx environments, while another applies a single-step oxidation scheme without chemical aging. Two emission inventories are used for discussion of emission uncertainties. The slopes of the airborne OA levels versus Ox (i.e., O3 + NO2) show SOA formation normalized with respect to photochemical activity and are used for specific evaluation of the OA scheme in the model. The simulated slopes were overestimated slightly by factors of 1.1, 1.7 and 1.3 with respect to those observed for the three airborne measurements, when the most realistic "high-NOx" yields for traditional SOA formation in the VBS scheme are used in the model. In addition, these slopes are relatively stable from one day to another, which suggests that they are characteristic for the given megacity plume environment. The configuration with increased primary

  3. Revision of the tsunami catalogue affecting Turkish coasts and surrounding regions

    Directory of Open Access Journals (Sweden)

    Y. Altinok

    2011-02-01

    Full Text Available The coasts of Turkey have been hit by tsunamis in the past. The first national earthquake-tsunami catalogues were compiled in the early 1980s while the most up-to-date tsunami catalogues are mainly the products of recent European projects. The EU projects GITEC and GITEC-TWO (Genesis and Impact of Tsunamis on the European Coasts and TRANSFER (Tsunami Risk ANd Strategies For the European Region have added important contributions in establishing and developing unified criteria for tsunami parameterisation, standards for the quality of the data, the data format and the database general architecture. On the basis of these new aspects and based on recent marine geophysical data, tsunamigenic earthquakes, tsunami intensities and their reliability have been revised. The current version of the database contains 134 events, most of which have affected the Turkish coasts seriously during the last 3500 years. The reliability index of 76 events was "probable" and "definite", so that they could be used for assessment of the risk along the Turkish coastal region and for implementation of prevention policies.

  4. Shear wave velocity structure of the Anatolian Plate and surrounding regions using Ambient Noise Tomography

    Science.gov (United States)

    Delph, J. R.; Beck, S. L.; Zandt, G.; Biryol, C. B.; Ward, K. M.

    2013-12-01

    The Anatolian Plate consists of various lithospheric terranes amalgamated during the closure of the Tethys Ocean, and is currently extruding to the west in response to a combination of the collision of the Arabian plate in the east and the roll back of the Aegean subduction zone in the west. We used Ambient Noise Tomography (ANT) at periods structure of the Anatolian Plate. We computed a total of 13,779 unique cross-correlations using one sample-per-second vertical component broadband seismic data from 215 stations from 8 different networks over a period of 7 years to compute fundamental-mode Rayleigh wave dispersion curves following the method of Benson et al. (2007). We then inverted the dispersion data to calculate phase velocity maps for 11 periods from 8 s - 40 s throughout Anatolia and the Aegean regions (Barmin et al. 2001). Using smoothed Moho values derived from Vanacore et al. (2013) in our starting models, we inverted our dispersion curves using a linear least-squares iterative inversion scheme (Herrmann & Ammon 2004) to produce a 3-D shear-wave velocity model of the crust and uppermost mantle throughout Anatolia and the Aegean. We find a good correlation between our seismic shear wave velocities and paleostructures (suture zones) and modern deformation (basin formation and fault deformation). The most prominent crustal velocity contrasts occur across intercontinental sutures zones, resulting from the juxtaposition of the compositionally different basements of the amalgamated terranes. At shallow depths, seismic velocity contrasts correspond closely with surficial features. The Thrace, Cankiri and Tuz Golu basins, and accretionary complexes related to the closure of the Neotethys are characterized by slow shear wave velocities, while the Menderes and Kirsehir Massifs, Pontides, and Istanbul Zone are characterized by fast velocities. We find that the East Anatolia Plateau has slow shear-wave velocities, as expected due to high heat flow and active

  5. Regional water balance for the Waste Isolation Pilot Plant (WIPP) site and surrounding area

    International Nuclear Information System (INIS)

    Hunter, R.L.

    1985-12-01

    The WIPP water-balance study area defined here comprises approx.2000 mi 2 in Eddy and Lea Counties, southeastern New Mexico. Inflows to the study area are precipitation (roughly 1.47 x 10 6 ac-ft/y), surface water (roughly 1.1 x 10 5 ac-ft/y), water imported by municipalities and industries (roughly 3 x 10 4 ac-ft/y), and ground water (volume not estimated). Outflows from the area are evapotranspiration (roughly 1.5 x 10 6 ac-ft/y), surface water (roughly 1.2 x 10 5 ac-ft/y), and possibly some ground water. The volume of surface and ground water in storage in Nash Draw has increased since the beginning of potash refining. Regional ground-water flow in aquifers above the Salado Formation is from the northeast to the southwest, although this pattern is interrupted by Clayton Basin, Nash Draw, and San Simon Swale. The Pecos River is the only important perennial stream. Most of the area has no integrated surface-water drainage. The available data suggest that approx.1600 mi 2 of the study area are hydrologically separate from Nash Draw and the WIPP site. Ground water north of Highway 180 apparently discharges into Clayton Basin and evaporates. Water in San Simon Swale apparently percolates downward and flows to the southeast. Data are inadequate to create a water budget for the Nash Draw-WIPP site hydrologic system alone, although an attempt to do so can provide guidance for further study

  6. Far-infrared and CO observations of NGC 6357 and regions surrounding NGC 6357 and NGC 6334

    International Nuclear Information System (INIS)

    McBreen, B.; Jaffe, D.T.; Fazio, G.G.

    1983-01-01

    We have surveyed two 1.7 square degree sections of the galactic plane at 70 μm with one-arcminute resolution. The scanned areas included the giant southern H II region complexes NGC 6357 and NGC 6334. Nineteen far-infrared sources were observed. The sources range in luminosity from 1.6 x 10 4 to 5.5 x 10 5 L/sub sun/ . We present far-infrared continuum and CO line observations of NGC 6357. Four far-infrared sources were found in this complex and for one of these sources the exciting stars are identified. We present far-infrared and CO observations of sources in the field surrounding NGC 6357 and NGC 6334. The far-infrared sources coincide frequently with CO line temperature peaks. The CO clouds which surround the far-infrared sources have similar 13 CO column densities. Two of the far-infrared sources in the field have associated OH and H 2 O maser emission and compact H II regions

  7. Regional magnetic and gravity features of the Gibson Dome area and surrounding region, Paradox Basin, Utah : a preliminary report

    Science.gov (United States)

    Hildenbrand, T.G.; Kucks, R.P.

    1983-01-01

    Analyses of regional gravity and magnetic anomaly maps have been carried out to assist in the evaluation of the Gibson Dome area as a possible repository site for high-level radioactive waste. Derivative, wavelength-filtered, and trend maps were compiled to aid in properly locating major geophysical trends corresponding to faults, folds, and lithologic boundaries. The anomaly maps indicate that Paradox Basin is characterized by a heterogeneous Precambrian basement, essentially a metamorphic complex of gneisses and schist intruded by granitic rocks and mafic to ultramafic bodies. Interpreted Precambrian structures trend predominantly northwest and northeast although east-west trending features are evident. Prominent gravity lows define the salt anticlines. Structural and lithologic trends in the Gibson Dome area are closely examined. Of greatest interest is a series of circular magnetic highs trending west-northwest into the Gibson Dome area. Further study of the exact definition and geologic significance of this series of anomalies is warranted.

  8. 3-D mechanical modeling of the eastward escape flow pattern around the Northeastern Tibetan plateau and surrounding regions

    Science.gov (United States)

    Cheng, H.; Shi, Y.; Zhang, H.

    2016-12-01

    Since the last 50 million years, 2500km shorting of Indian Plate moving north collided with the Eurasian Plate has resulted in rapid uplift of the Tibetan Plateau shaped into the most intensive and extensive orogen on earth (Molnar and Tapponnier, 1975; Li et al., 2013). Based on previous geological and geophysical investigations (Royden et al., 1997; Clark and Royden, 2000), two end-member models of the entire Tibetan Plateau are proposed: thin visous sheet model and lateral escape model. However, when we scope into a special local area, for example, Northeastern Tibetan plateau and surrounding regions, end-member models could change to lower crustal flow model and upper crust shorting model. Recently, with vigorous geophysical observations, more data such as differential traveltime tomography and seismic velocity structure in the Tibetan Plateau actually reveal that the eastward crustal flow from the central Tibetan plateau is expected to divert north-eastward and south-eastward around the rigid Sichuan basin (Royden et al., 1997, 2008; Clark and Royden, 2000). Moreover, both the P-wave polarization tomography and gravitational anomaly and the GPS data from the intensive crustal movement monitoring network in China show that the north-eastward crustal flow divide two direction due to the Ordos Block as a barrier with rigid, cold and stable crust. In order to investigate mechanical of the eastward escape flow pattern around the Northeastern Tibetan plateau and surrounding regions, especially along the Xi'an-Taiyuan-Datong, we construct 3-D geological finite element model with high resolution topography and non-homogeneous strata. For the uncertainties of computational parameters, such as the depth and width and viscosity coefficient of the middle-lower crust, and the pressure differences, several models were tested to analyze the spatial distribution of curst flow and try to known about the uplift of Datong in Shanxi Province.

  9. Cometary water-group ions in the region surrounding Comet Giacobini-Zinner - Distribution functions and bulk parameter estimates

    Science.gov (United States)

    Staines, K.; Balogh, A.; Cowley, S. W. H.; Richardson, I. G.; Sanderson, T. R.; Tsurutani, B. T.

    1991-01-01

    The bulk parameters (number density and thermal energy density) of cometary water-group ions in the region surrounding Comet Giacobini-Zinner have been derived using data from the EPAS instrument on the ICE spacecraft. The derivation is based on the assumption that the pick-up ion distribution function is isotropic in the frame of the bulk flow, an approximation which has previously been shown to be reasonable within about 400,000 km of the comet nucleus along the spacecraft trajectory. The transition between the pick-up and mass-loaded regions occurs at the cometary shock, which was traversed at a cometocentric distance of about 100,000 km along the spacecraft track. Examination of the ion distribution functions in this region, transformed to the bulk flow frame, indicates the occurrence of a flattened distribution in the vicinity of the local pick-up speed, and a steeply falling tail at speeds above, which may be approximated as an exponential in ion speed.

  10. 12-Digit Watershed Boundary Data 1:24,000 for EPA Region 2 and Surrounding States (NAT_HYDROLOGY.HUC12_NRCS_REG2)

    Data.gov (United States)

    U.S. Environmental Protection Agency — 12 digit Hydrologic Units (HUCs) for EPA Region 2 and surrounding states (Northeastern states, parts of the Great Lakes, Puerto Rico and the USVI) downloaded from...

  11. The plasma-sheath boundary region

    International Nuclear Information System (INIS)

    Franklin, R N

    2003-01-01

    In this review an attempt is made to give a broad coverage of the problem of joining plasma and sheath over a wide range of physical conditions. We go back to the earliest works quoting them, where appropriate, to understand what those who introduced the various terms associated with the structure of the plasma-sheath had in mind. We try to bring out the essence of the insights that have been gained subsequently, by quoting from the literature selectively, indicating how misunderstandings have arisen. In order to make it accessible to the generality of those currently working in low temperature plasmas we have sought to avoid mathematical complexity but retain physical insight, quoting from published work where appropriate. Nevertheless, in clarifying my own ideas I have found it necessary to do additional original work in order to give a consistent picture. In this way I have sought to bring together work in the late 1920s, the 1960s, and now mindful of the commercial importance of plasma processing, work over the past 15 years that adds to the general understanding. (topical review)

  12. High-Frequency Ground-Motion Parameters from Weak-Motion Data in the Sicily Channel and Surrounding Regions

    Science.gov (United States)

    D'Amico, Sebastiano; Akinci, Aybige; Pischiutta, Marta

    2018-03-01

    In this paper we characterize the high frequency (1.0 - 10 Hz) seismic wave crustal attenuation and the source excitation in the Sicily Channel and surrounding regions using background seismicity from weak-motion database. The data set includes 15995 waveforms related to earthquakes having local magnitude ranging from 2.0 to 4.5 recorded between 2006 and 2012. The observed and predicted ground motions form the weak-motion data are evaluated in several narrow frequency bands from 0.25 to 20.0 Hz. The filtered observed peaks are regressed to specify a proper functional form for the regional attenuation, excitation and site specific term separately. The results are then used to calibrate effective theoretical attenuation and source excitation models using the Random Vibration Theory (RVT). In the log-log domain, the regional seismic wave attenuation and the geometrical spreading coefficient are modeled together. The geometrical spreading coefficient, g (r), modeled with a bilinear piecewise functional form and given as g (r) ∝ r-1.0 for the short distances (r selected reference distance with a magnitude independent roll-off spectral parameter, κ 0.04 s and with a Brune stress drop parameter increasing with moment magnitude, from Δσ = 2 MPa for Mw = 2.0 to Δσ = 13 MPa for Mw = 4.5. For events M≤4.5 (being Mwmax = 4.5 available in the dataset) the stress parameters are obtained by correlating the empirical/excitation source spectra with the Brune spectral model as function of magnitude. For the larger magnitudes (Mw>4.5) outside the range available in the calibration dataset where we do not have recorded data, we extrapolate our results through the calibration of the stress parameters of the Brune source spectrum over the Bindi et al. (2011) ground motion prediction equation (GMPE) selected as a reference model (hereafter also ITA10).

  13. The plasma-wall interaction region: a key low temperature plasma for controlled fusion

    International Nuclear Information System (INIS)

    Counsell, G F

    2002-01-01

    The plasma-wall interaction region of a fusion device provides the interface between the hot core plasma and the material surfaces. To obtain acceptably low levels of erosion from these surfaces requires most of the power leaving the core to be radiated. This is accomplished in existing devices by encouraging plasma detachment, in which the hot plasma arriving in the region is cooled by volume recombination and ion-neutral momentum transfer with a dense population of neutrals recycled from the surface. The result is a low temperature (1 eV e e >10 19 m -3 ) but weakly ionized (n 0 >10 20 m -3 , n e /n 0 <0.1) plasma found nowhere else in the fusion environment. This plasma provides many of the conditions found in industrial plasmas exploiting plasma chemistry and the presence of carbon in the region (in the form of carbon-fibre composite used in the plasma facing materials) can result in the formation of deposited hydrocarbon films. The plasma-wall interaction region is therefore among the most difficult in fusion to model, requiring an understanding of atomic, molecular and surface physics issues

  14. ANTHEM simulation of the early time magnetic field penetration of the plasma surrounding a high density Z-pinch

    International Nuclear Information System (INIS)

    Mason, R.J.

    1989-01-01

    The early time penetration of magnetic field into the low density coronal plasma of a Z-pinch fiber is studied with the implicit plasma simulation code ANTHEM. Calculations show the emission of electrons from the cathode, pinching of the electron flow, magnetic insulation of the electrons near the anode, and low density ion blow off. PIC-particle ion calculations show a late time clumping of the ion density not seen with a fluid ion treatment. 4 refs., 4 figs

  15. Isostatic and Decompensative Gravity Anomalies of the Arabian Plate and Surrounding Regions: a Key for the Crustal Structure

    Science.gov (United States)

    Kaban, M. K.; El Khrepy, S.; Al-Arifi, N. S.

    2016-12-01

    The isostatic anomalies are often considered as one of the most useful correction of the gravity field for investigation of the upper crust structure in many practical applications. By applying this correction, a substantial part of the effect of deep density heterogeneity, which dominates in the Bouguer gravity anomaly, can be removed. With this approach, it is not even necessary to know the deep density structure of the crust and upper mantle in details; it is sufficient to prescribe some type of compensation (regional vs. local) and a compensation depth. However, even when all the parameters are chosen correctly, this reduction of the gravity field does not show the full gravity effect of unknown anomalies in the crust. The last ones should be also compensated to some extent; therefore their impact is substantially reduced by the isostatic compensation. Long ago (Cordell et al., 1991), it was suggested a so-called decompensative correction of the isostatic anomalies, which provides a possibility to separate these effects. However, the decompensative correction is very sensitive to the parameters of the compensation scheme. In the present study we analyse the ways to choose these parameters and extend this approach by assuming a possibility for the regional compensation via elastic deformations of the lithosphere. Based on this technique, we estimate the isostatic and decompensative anomalies for the Arabian plate and surrounding regions. The parameters of the isostatic model are chosen based on previous studies. It was demonstrated that the decompensative correction is very significant at the mid-range wavelengths and may exceed 100 mGal, therefore ignoring this effect would lead to wrong conclusions about the upper crust structure. The total amplitude of the decompensative anomalies reaches ±250 mGal, evidencing for both, large density anomalies of the upper crust (including sediments) and strong isostatic disturbances of the lithosphere. These results improve

  16. Human dynamics and forest management: a baseline assessment of the socioeconomic characteristics of the region surrounding the El Yunque National Forest

    Science.gov (United States)

    Kathleen McGinley

    2016-01-01

    In this paper, I examine the socioeconomic dynamics and human–environment interactions in the region surrounding the El Yunque National Forest (EYNF) in northeastern Puerto Rico and their implications for policy development and sustainable resource use. As part of a larger, comprehensive assessment of the conditions and trends of the EYNF and broader region, I...

  17. Analyzing the Implications of Climate Data on the Rainfall Frequency Spectrum: Case Study of Knoxville, Tennessee and Surrounding Region

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester, Linda M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Omitaomu, Olufemi A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Parish, Esther S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-01

    Modeled daily precipitation values are used to determine changes in percentile rainfall event depths, for planning and mitigation of stormwater runoff, over past (1980-2005) and future (2025-2050) periods for Knoxville, Tennessee and the surrounding area.

  18. Smart Surroundings

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Jansen, P.G.; Lijding, M.E.M.; Scholten, Johan

    2004-01-01

    Ambient systems are networked embedded systems integrated with everyday environments and supporting people in their activities. These systems will create a Smart Surrounding for people to facilitate and enrich daily life and increase productivity at work. Such systems will be quite different from

  19. Plasma potential measurements in the edge region of the ISTTOK plasma, using electron emissive probes

    International Nuclear Information System (INIS)

    Ionita, C.; Balan, P.; Schrittwieser, R.; Cabral, J.A.; Fernandes, H.; Figueiredo, H. F.C.; Varandas, C.

    2001-01-01

    We have recently started to use electron-emissive probes for direct measurements of the plasma potential and its fluctuations in the edge region of the plasma ring in the tokamak ISTTOK in Lisbon, Portugal. This method is based on the fact that the electron emission current of such a probe is able to compensate electron temperature variations and electron drifts, which can occur in the edge plasma region of magnetized fusion devices, and which are making measurements with cold probes prone to errors. In this contribution we present some of the first results of our investigations in ISTTOK.(author)

  20. Experimental study on dynamic stabilization of the MHD instability in pinch plasmas surrounded by a conducting shell

    International Nuclear Information System (INIS)

    Yamamoto, Shunji; Ishii, Shozo; Kawamoto, Shigeshi; Hayashi, Izumi

    1981-01-01

    Experimental study on the dynamic stabilization of MHD instability with a pinch plasma generator was done, and the results were compared with the theoretical works. The previous results of theoretical analysis showed that a conducting shell worked effectively for the dynamic stabilization of MHD instability. The present experiment was carried out with a linear plasma generator which consisted of a discharge tube, a coil and a conducting shell. The macroscopic behavior of plasma was observed with an image converter camera, and the phenomena due to the instability was measured by a magnetic probe. A sine-cosine coil was employed for the observation of the growth of instability. The following results were obtained. When the frequency of RF current for dynamic stabilization was larger than the growth rate of instability, the experimental results were in agreement with the theoretical ones. The effect of a conducting shell was clearly seen. For the helical instability of short wave length, the dynamic stabilization was easily obtained even without a conducting shell. The self-reversal phenomena due to the helical instability of short wave length was suppressed by the RF current along the axis of a discharge tube. (Kato, T.)

  1. Evolution of active region loop plasma

    International Nuclear Information System (INIS)

    Krall, K.R.; Antiochos, S.K.

    1980-01-01

    We investigate numerically the adjustment of coronal active-region loops to changes in their heating rate. The one-dimensional hydrodynamic equations are solved subject to boundary conditions in which heat flux-induced mass exchange between coronal and chromospheric components is allowed. The calculated evolution of physical parameters suggests that (1) mass supplied during chromospheric evaporation is much more effective in moderating coronal temperature excursions than when downward heat flux if dissipated by a static chromosphere, and (2) the method by which rhe chromosphere responds to changing coronal conditions can significantly influence coronal readjustment time scales. Observations are cited which illustrate the range of possible fluctuations in the heating rates

  2. Climatology and trend of wind power resources in China and its surrounding regions: a revisit using Climate Forecast System Reanalysis data

    Science.gov (United States)

    Lejiang Yu; Shiyuan Zhong; Xindi Bian; Warren E. Heilman

    2015-01-01

    The mean climatology, seasonal and interannual variability and trend of wind speeds at the hub height (80 m) of modern wind turbines over China and its surrounding regions are revisited using 33-year (1979–2011) wind data from the Climate Forecast System Reanalysis (CFSR) that has many improvements including higher spatial resolution over previous global reanalysis...

  3. Chapter B: Regional Geologic Setting of Late Cenozoic Lacustrine Diatomite Deposits, Great Basin and Surrounding Region: Overview and Plans for Investigation

    Science.gov (United States)

    Wallace, Alan R.

    2003-01-01

    Freshwater diatomite deposits are present in all of the Western United States, including the Great Basin and surrounding regions. These deposits are important domestic sources of diatomite, and a better understanding of their formation and geologic settings may aid diatomite exploration and land-use management. Diatomite deposits in the Great Basin are the products of two stages: (1) formation in Late Cenozoic lacustrine basins and (2) preservation after formation. Processes that favored long-lived diatom activity and diatomite formation range in decreasing scale from global to local. The most important global process was climate, which became increasingly cool and dry from 15 Ma to the present. Regional processes included tectonic setting and volcanism, which varied considerably both spatially and temporally in the Great Basin region. Local processes included basin formation, sedimentation, hydrology, and rates of processes, including diatom growth and accumulation; basin morphology and nutrient and silica sources were important for robust activity of different diatom genera. Only optimum combinations of these processes led to the formation of large diatomite deposits, and less than optimum combinations resulted in lakebeds that contained little to no diatomite. Postdepositional processes can destroy, conceal, or preserve a diatomite deposit. These processes, which most commonly are local in scale, include uplift, with related erosion and changes in hydrology; burial beneath sedimentary deposits or volcanic flows and tuffs; and alteration during diagenesis and hydrothermal activity. Some sedimentary basins that may have contained diatomite deposits have largely been destroyed or significantly modified, whereas others, such as those in western Nevada, have been sufficiently preserved along with their contained diatomite deposits. Future research on freshwater diatomite deposits in the Western United States and Great Basin region should concentrate on the regional

  4. Changes in regional plasma extravasation in rats following endotoxin infusion

    International Nuclear Information System (INIS)

    van Lambalgen, A.A.; van den Bos, G.C.; Thijs, L.G.

    1987-01-01

    Regional differences in plasma extravasation during endotoxin shock in rats and a possible relationship with changes in regional blood flow were studied with radioactive isotopes ( 125 I-HSA, 51Cr-labeled red blood cells, microspheres) in anesthetized rats (pentobarbital). Shock was induced by intravenous infusion of endotoxin (Eschericia coli; 10 mg X kg-1) for 60 min (starting at t = 0); at t = 120 min, the experiments were terminated. These rats (n = 8) were compared with time-matched control rats (n = 8). A third group (rats killed 7.5 min after injection of 125 I-HSA, i.e., no extravasation; n = 8) served as baseline. The amount of plasma extravasated in 2 hr of endotoxin shock was significantly increased over control values in skin (by 67%), colon (88%), skeletal muscle (105%), stomach (230%), pancreas (300%), and diaphragm (1300%). Losses of 125 I-HSA into intestinal lumen and peritoneal cavity had also increased over control values by 146 and 380%, respectively. Blood flow was compromised in most organs except heart and diaphragm. Extravasation when normalized for total plasma supply was correlated with total blood supply; the more the blood supply decreased, the higher the normalized extravasation. In the diaphragm, however, blood supply and plasma leakage increased together. Decreased blood supply and plasma extravasation may be related but they could also be simultaneously occurring independent phenomena with a common origin

  5. Interferometric density measurements in the divertor and edge plasma regions for the additionally heated JT-60 plasmas

    International Nuclear Information System (INIS)

    Fukuda, T.; Yoshida, H.; Nagashima, A.; Ishida, S.; Kikuchi, M.; Yokomizo, H.

    1989-01-01

    The first divertor plasma density measurement and the interferometric edge plasma density measurement with boundary condition preserving millimeter waveguides were demonstrated to elucidate the mutual correlation among the divertor plasma, scrape-off layer plasma and the bulk plasma properties in the additionally heated JT-60 plasmas. The electron density in the divertor region exhibited a nonlinear dependence on the bulk plasma density for the joule-heated plasmas. When neutral beam heating is applied on the plasmas with the electron density above 2x10 19 /m 3 , however, the bulk plasma density is scraped off from the outer region to lead to density clamping, and the electron density in the divertor region rapidly increases over 1x10 20 /m 3 , from which we can deduce that the particle flow along the magnetic field is dominant, resulting in the apparent degradation of the particle confinement time. As for the case when neutral beam injection is applied to low-density plasmas, the bulk plasma electron density profile becomes flattened to yield a smaller density increase in the divertor region and no density clamping of the bulk plasma was observed. Simulation analysis which correlates the transport of the divertor plasma and the scrape-off layer plasma was also carried out to find the consistency with the experimental results. (orig.)

  6. Coupled plasma-neutral transport model for the scrape-off region

    International Nuclear Information System (INIS)

    Galambos, J.D.; Peng, Y.K.M.; Heifetz, D.

    1985-03-01

    Analysis of the scrape-off region requires treatment of the plasma transport along and across the field lines and inclusion of the neutral transport effects. A method for modeling the scrape-off region that is presented here uses separate models for each of these aspects that are coupled together through an iteration procedure that requires only minimal numerical effort. The method is applied here to estimate the neutral pumping rates in the pump-limiter and divertor options for a proposed deuterium-tritium (D-T) ignition experiment. High neutral recycling in the vicinity of the neutralizer plate dramatically affects pumping rates for both the pump-limiter and divertor. In both cases, the plasma flow into the channel surrounding the neutralizer plate is greatly reduced by the neutral recycling. The fraction of this flow that is pumped can be large (> 50%), but in general it is dependent on the particular geometry and plasma conditions. It is estimated that pumping speeds approximately greater than 10 5 L/s are adequate for the exhaust requirements in the pump-limiter and the divertor cases. Also, high neutral recycling on the front surface of the limiter tends to increase the neutral pumping rate

  7. Dusty plasma in the region of the lunar terminator

    Energy Technology Data Exchange (ETDEWEB)

    Popel, S. I., E-mail: popel@iki.rssi.ru; Zelenyi, L. M. [Russian Academy of Sciences, Space Research Institute (Russian Federation); Atamaniuk, B. [Polish Academy of Sciences, Space Research Center (Poland)

    2016-05-15

    Dusty plasma in the region of the lunar terminator is considered. It is shown that, in this region, a structure resembling a plasma sheath forms near the lunar surface. This sheath creates a potential barrier, due to which electrons over the illuminated part of the Moon are confined by electrostatic forces. The width of the sheath-like structure is on the order of the ion Debye length. In this structure, significant (about several hundred V/m) electric fields arise, which lift charged micron-size dust grains to heights of several tens of centimeters. The suggested effect may be used to explain the glow observed by the Surveyor spacecraft over the lunar terminator.

  8. Definition of the continent-ocean boundary of India and the surrounding oceanic regions from Magsat data

    Science.gov (United States)

    Singh, B. P.; Rajaram, Mita; Bapat, V. J.

    1991-06-01

    Magsat studies over the Indian region and adjoining areas show that the continental-oceanic contrasts appear more distinctly in the equivalent magnetization solution than in the anomaly maps. The vertical component ( Z) is found to be more useful for the equatorial regions. It is also noted that, in general, the continental crust has a higher magnetization than the oceanic crust. Further, the continental crust seems to extend into the Arabian Sea across a part of the west coast. A similar continuation is seen in the northern part of the Bay of Bengal. The west coast result is corroborated using land and marine Bouguer gravity anomalies.

  9. Use of a culture independent method to analyze the diversity of soil fungi surrounding Chroogomphus rutilus in the Beijing region of China

    DEFF Research Database (Denmark)

    Liu, Yu; Wang, Shouxian; Yin, Yonggang

    2012-01-01

    habitat to facilitate its large-scale cultivation. A culture-independent molecular approach—a powerful technology for microbiological ecology studies—was used to investigate the diversity of soil fungal communities in samples surrounding C. rutilus from the Beijing region of China. Metagenomic DNA...... was isolated from soil samples collected around C. rutilus, and an internal transcribed spacer (ITS) gene library was constructed. Subsequently, polymerase chain reaction products were digested with HinfI, HaeIII, MspI, TaqI, or MboI. Clones were selected and sequenced based on their restriction fragment...... length polymorphisms. The diversity of the fungi represented by their ITS sequences was analyzed. Our results indicate the presence of numerous fungi in the C. rutilus habitat. This study is the first demonstration of the fungal ecology surrounding C. rutilus using a culture independent method...

  10. Evaluation of tidal stream energy and its impacts on surrounding dynamics in the Eastern Region of Pingtan Island, China

    Science.gov (United States)

    Wu, He; Wang, Xin; Wang, Bingzhen; Bai, Yang; Wang, Peitao

    2017-11-01

    Using an improved FVCOM numerical model, combined with the momentum-sinking scheme based on the structural characteristics of specific turbines, this study analyzed the temporal and spatial distributions of tidal energy resources before and after the deployment of tidal turbines near Pingtan Island, China. Considering factors such as the distribution of tidal stream energy, bathymetry, topography, and the design parameters of the turbines, an appropriate location for a demonstration tidal turbine was selected and the corresponding energy resource was evaluated. Several sites with strong tidal streams were considered: south of the northern cape, east of the southern cape, and the southern end of Haitan Bay. The former was thought most suitable for the deployment of a tidal energy turbine, with projected power generation for approximately 470 h per month. The average power of this demonstration was about 2.4 kW, and the annual electricity output was approximately 17.47 MWh. The intervention of the turbine device had little influence on the near-field tidal stream or water level. The tidal stream was reduced slightly in the area south of the northern cape, although the effect weakened further from the turbine. Conversely, the velocity increased slightly on both sides of the demonstration site. The difference in current speed with and without the turbine was greater at slack tide than still tide. The influence of turbine operation on water level was minor. The method adopted in this study can be considered a reference for the selection of sites for the demonstration of tidal stream energy. However, the method is unable describe the dynamic characteristics of the turbulent flow surrounding the deployed turbines, which has an important role regarding the optimal designs of the turbine blade and pile foundations. Therefore, we will continue to work to improve this model in future research.

  11. Plasma IGF-I, INSL3, testosterone, inhibin concentrations and scrotal circumferences surrounding puberty in Japanese Black beef bulls with normal and abnormal semen.

    Science.gov (United States)

    Weerakoon, W W P N; Sakase, M; Kawate, N; Hannan, M A; Kohama, N; Tamada, H

    2018-07-01

    The relationships between semen abnormalities and peripheral concentrations of testicular and metabolic hormones in beef bulls are unclear. Here we compared plasma insulin-like growth factor I (IGF-I), insulin-like peptide 3 (INSL3), testosterone, inhibin concentrations, and scrotal circumferences surrounding puberty in Japanese Black beef bulls (n = 66) with normal or abnormal semen. We collected blood samples and measured scrotal circumferences monthly from 4 to 24 months of age. Semen was collected weekly from 12 months until at least 18 months of age. Fresh semen was evaluated for semen volume, sperm motility, concentrations, and morphological defects. The normal fresh semen was frozen by a standard method and examined for post-thaw sperm motility and fertility. Bulls were classified as having either normal post-thaw semen (n = 45) or abnormal semen (n = 21, when at least one of the above test items was abnormal for 6 months). Abnormal semen was classified into abnormal fresh or low-fertility post-thaw which evaluated for rates of transferable embryos. The abnormal fresh was categorized as having sperm morphological defects, low motility, and morphological defects plus low motility. Scrotal circumferences were smaller for the abnormal-semen group vs. the normal-semen group at 20 and 24 months (p IGF-I, INSL3, and inhibin concentrations in the abnormal-semen group were lower than those of the normal-semen group (p IGF-I; 6, 9, 11-14, 17, and 20-21 months for INSL3; 5, 8-13, 16, 17, 19, and 20 months for inhibin). The plasma testosterone concentrations were lower in the abnormal-semen bulls vs. normal-semen bulls only at 22 months (p IGF-I and inhibin concentrations for low-fertility post-thaw semen (p IGF-I, INSL3, and inhibin surrounding puberty may be associated with semen aberration in beef bulls. Notably, the combined sperm abnormality of morphological defects and low motility in fresh semen could involve lowered INSL3, whereas the low

  12. Environment of the Gamma-Ray Burst GRB 971214: A Giant H ii Region Surrounded by a Galactic Supershell.

    Science.gov (United States)

    Ahn

    2000-02-10

    Among a number of gamma-ray bursts whose host galaxies are known, GRB 971214 stands out for its high redshift (z>/=3) and the Lyalpha emission line having a P Cygni-type profile, which is interpreted to be a direct consequence of the expanding supershell. From a profile-fitting analysis, we estimate the expansion velocity of the supershell (vexp=1500 km s-1) and the neutral column density (NHi=1020 cm -2). The redshift z=3.418 of the host galaxy proposed by Kulkarni et al. in 1998 has been revised to be z=3.425 from our profile analysis. The observed Lyalpha profile is fitted well by a Gaussian curve, which yields the Lyalpha luminosity LLyalpha=&parl0;1.8+/-0.8&parr0;x1042 ergs s-1. Assuming that the photon source is a giant H ii region, we deduce the electron number density in the H ii region ne=&parl0;40+/-10&parr0;&parl0;L/LLyalpha&parr0;0.5&parl0;R/100 pc&parr0;-1.5 cm-3, which corresponds to the illumination by about 104 O5 stars. We estimate the star formation rate to be RSF=7+/-3 M middle dot in circle yr-1 with the internal and the Galactic extinction corrected. The theory on the evolution of supernova remnants is used to propose that the supershell is at the adiabatic phase, with its radius R=18E1&solm0;253 pc, its age t=4.7x103E1&solm0;253 yr, and the density of the ambient medium n1=5.4E-1&solm0;253 cm-3, where E53=E&solm0;1053 ergs; we estimate the kinetic energy of the supershell to be Ek=7.3x1052E53 ergs. These values are consistent with the hypothesis that the supershell is the remnant of a gamma-ray burst. We note similarities between supershells found in nearby galaxies and remote primeval galaxies and propose that the gamma-ray burst may have occurred in a giant H ii region whose environment is similar to that in star-forming galaxies.

  13. Topogrid Derived 10 Meter Resolution Digital Elevation Model of the Shenandoah National Park and Surrounding Region, Virginia

    Science.gov (United States)

    Chirico, Peter G.; Tanner, Seth D.

    2004-01-01

    Explanation The purpose of developing a new 10m resolution DEM of the Shenandoah National Park Region was to more accurately depict geologic structure, surfical geology, and landforms of the Shenandoah National Park Region in preparation for automated landform classification. Previously, only a 30m resolution DEM was available through the National Elevation Dataset (NED). During production of the Shenandoah10m DEM of the Park the Geography Discipline of the USGS completed a revised 10m DEM to be included into the NED. However, different methodologies were used to produce the two similar DEMs. The ANUDEM algorithm was used to develop the Shenadoah DEM data. This algorithm allows for the inclusion of contours, streams, rivers, lake and water body polygons as well as spot height data to control the elevation model. A statistical analysis using over 800 National Geodetic Survey (NGS) first and second order vertical control points reveals that the Shenandoah10m DEM, produced as a part of the Appalachian Blue Ridge Landscape project, has a vertical accuracy of ?4.87 meters. The metadata for the 10m NED data reports a vertical accuracy of ?7m. A table listing the NGS control points, the elevation comparison, and the RMSE for the Shenandoah10m DEM is provided. The process of automated terrain classification involves developing statistical signatures from the DEM for each type of surficial deposit and landform type. The signature will be a measure of several characteristics derived from the elevation data including slope, aspect, planform curvature, and profile curvature. The quality of the DEM is of critical importance when extracting terrain signatures. The highest possible horizontal and vertical accuracy is required. The more accurate Shenandoah 10m DEM can now be analyzed and integrated with the geologic observations to yield statistical correlations between the two in the development of landform and surface geology mapping projects.

  14. Diagnostic radiopharmaceuticals for localization in target tissues exhibiting a regional pH shift relative to surrounding tissues

    International Nuclear Information System (INIS)

    Blau, M.; Kung, H.F.

    1985-01-01

    Diagnostic radiopharmaceutical compounds are provided which are capable of entering a target tissue or a target organ by passive diffusion through cell walls and which are effectively accumulated and retained within the target tissue or organ due to a regional pH shift. Such compounds are desirably readily accessible synthetically using readily available radionuclides. The compound comprises a radioactive isotope of an element in chemical combination with at least one amine group and preferably with at least two secondary or tertiary amine groups. The radioactive element is an element other than iodine emitting gamma ray, x-ray or positron radiation. When the element is a gamma ray emitting isotope, at least 75 percent of the number of emissions is emitted at energies of between 80 and 400 keV. The half-life of the isotope is usually between two minutes and 15 days. The compound has acid-base characteristics such that the state of ionization of the compound at the pH of the body is significantly different and usually less than its state of ionization at the intracellular pH of the target tissue. The compound has such lipid solubility characteristics that it is capable of ready penetration through cell walls, but within cells its lipid solubility is substantially decreased, whereby the ability of the compound to leave the target tissue is substantially diminished. Specific data relevant to di-beta-(piperidinoethyl)-selenide and di-beta-(morpholinoethyl)-selenide in rat brains are presented

  15. Botanical origin and chemical constituents of commercial Saposhnikoviae radix and its related crude drugs available in Shaanxi and the surrounding regions.

    Science.gov (United States)

    Maruyama, Takuro; Ezaki, Masami; Shiba, Mao; Yamaji, Hiroki; Yoshitomi, Taichi; Kawano, Noriaki; Zhu, Shu; Cheng, Xiao; Yokokura, Tsuguo; Yamamoto, Yutaka; Fuchino, Hiroyuki; Sun, Hang; Komatsu, Katsuko; Kawahara, Nobuo

    2018-01-01

    Saposhnikoviae radix (SR) is described in the Japanese Pharmacopoeia as a crude drug derived from the root of Saposhnikovia divaricata Schischkin (Umbelliferae). According to Flora of China, the root of Peucedanum ledebourielloides K. F. Fu is used as a regional substitute for SR. Therefore, we surveyed the botanical origin of the drug used in China, especially Shaanxi and the surrounding regions, through nucleotide sequence analysis of the internal transcribed spacer region of rDNA. As a result, several samples from Shaanxi () and Shanxi () provinces were identified as Peucedanum ledebourielloides. To prevent this substitute from being distributed as genuine SR, we developed a thin-layer chromatography analysis condition to enable a specific compound of this species to be easily detected. The specific compound was identified as xanthalin, based on 1D- and 2D-NMR and high-resolution mass spectrometry data. The established TLC conditions were as follows-extraction solvent, n-hexane; applied volume, 5 µL; chromatographic support, silica gel; developing solvent, n-hexane:ethyl acetate:acetic acid (20:10:1); developing length, 7 cm; detection, UV (365 nm); R f value, 0.4 (blue fluorescence; xanthalin).

  16. A regional high-resolution emission inventory of primary air pollutants in 2012 for Beijing and the surrounding five provinces of North China

    Science.gov (United States)

    Liu, Huanjia; Wu, Bobo; Liu, Shuhan; Shao, Panyang; Liu, Xiangyang; Zhu, Chuanyong; Wang, Yong; Wu, Yiming; Xue, Yifeng; Gao, Jiajia; Hao, Yan; Tian, Hezhong

    2018-05-01

    A high resolution regional emission inventory of typical primary air pollutants (PAPs) for the year 2012 in Beijing and the surrounding five provinces (BSFP) of North China is developed. It is compiled with the combination of bottom-up and top-down methods, based on city-level collected activity data and the latest updated specific emission factors for different sources. The considered sources are classified into 12 major categories and totally 36 subcategories with respect to their multi-dimensional characteristics, such as economic sector, combustion facility or industrial process, installed air pollution control devices, etc. Power plant sector is the dominant contributor of NOX emissions with an average contribution of 34.1%, while VOCs emissions are largely emitted from industrial process sources (33.9%). Whereas, other stationary combustion sources represent major sources of primary PM2.5, PM10 and BC emissions, accounting for 22.7%, 30.0% and 33.9% of the total emissions, respectively. Hebei province contributes over 34% of the regional total CO emissions because of huge volume of iron and steel production. By comparison, Shandong province ranks as the biggest contributor for NOX, PM10, PM2.5, SO2, VOCs and OC. Further, the BSFP regional total emissions are spatially distributed into grid cells with a high resolution of 9 km × 9 km using GIS tools and surrogate indexes, such regional population, gross domestic product (GDP) and the types of arable soils. The highest emission intensities are mainly located in Beijing-Tianjin-Tangshan area, Jinan-Laiwu-Zibo area and several other cities such as Shijiazhuang, Handan, and Zhengzhou. Furthermore, in order to establish a simple method to estimate and forecast PAPs emissions with macroscopic provincial-level statistical parameters in China, multi-parameter regression equations are firstly developed to estimate emissions outside the BSFP region with routine statistics (e.g. population, total final coal consumption

  17. ELECTRIC PROBE INVESTIGATION OF ARC ANODE REGION IN PLASMA TORCH

    Czech Academy of Sciences Publication Activity Database

    Chumak, Oleksiy; Hrabovský, Milan; Kavka, Tetyana

    2006-01-01

    Roč. 10, č. 4 (2006), s. 515-524 ISSN 1093-3611. [High technology plasma processes. Saint-Petersburg, 27.5.2006-4.6.2006] R&D Projects: GA ČR GA202/05/0669 Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma torch * arc * anode attachment * restrike * electric probes Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.343, year: 2006

  18. What is important in the surroundings in order to extend the healthy life period? A regional study of 19 older women in a northern part of Norway.

    Science.gov (United States)

    Minde, Gunn-Tove; Sæterstrand, Torill M

    2013-01-01

    Participating in a community with other retired individuals to increase life quality can be possible for the older persons. Cultural and ethnical background is important for their social identity. To identify what the informants think is important in their surroundings in order to extend their healthy life period. A structured questionnaire developed by the OCIN network. Nineteen elderly women aged 75 years or more were interviewed. This regional survey is a pilot study in Norway. The data were collected during 2 periods, in 2009 and 2010. The data are analyzed using a result scheme prepared by the network OCIN. Our findings show that this is a group of elderly women that are concerned with promoting their own health. The participants wish to take care of themselves, so they do not become a burden for society and the local authorities. The findings of this study suggest that participation in the local context is important for promoting health and well-being among elderly in all ethnicities. For the Sami elderly, this is particularly important because meeting equal-minded people helps them maintain their Sami identity. In the Sami culture and among the Sami elderly, it is important to be "strong" and "healthy". Due to these norms, the elderly Sami women try to live with their illnesses and are less eager to go to the doctor when they are seriously ill.

  19. Plasma Sprayed Tungsten-based Coatings and their Usage in Edge Plasma Region of Tokamaks

    Czech Academy of Sciences Publication Activity Database

    Matějíček, Jiří; Weinzettl, Vladimír; Dufková, Edita; Piffl, Vojtěch; Peřina, Vratislav

    2006-01-01

    Roč. 51, č. 2 (2006), s. 179-191 ISSN 0001-7043 Grant - others:Evropská unie EFDA Task TW-5-TVM-PSW (EU – Euratom) Institutional research plan: CEZ:AV0Z20430508; CEZ:AV0Z10480505 Keywords : plasma sprayed coatings * fusion * plasma facing components * tungsten * tokamak Subject RIV: BL - Plasma and Gas Discharge Physics

  20. Magnetic Separatrix as the Source Region of the Plasma Supply for an Active-region Filament

    Energy Technology Data Exchange (ETDEWEB)

    Zou, P.; Fang, C.; Chen, P. F.; Yang, K. [School of Astronomy and Space Science, Nanjing University, Nanjing 210023 (China); Cao, Wenda [Big Bear Solar Observatory, New Jersey Institute of Technology, 40386 North Shore Lane, Big Bear City, CA 92314 (United States)

    2017-02-10

    Solar filaments can be formed via chromospheric evaporation followed by condensation in the corona or by the direct injection of cool plasma from the chromosphere to the corona. We here confirm with high-resolution H α data observed by the 1.6 m New Solar Telescope of the Big Bear Solar Observatory on 2015 August 21 that an active-region filament is maintained by the continuous injection of cold chromospheric plasma. We find that the filament is rooted along a bright ridge in H α , which corresponds to the intersection of a magnetic quasi-separatrix layer with the solar surface. This bright ridge consists of many small patches whose sizes are comparable to the width of the filament threads. It is found that upflows originate from the brighter patches of the ridge, whereas the downflows move toward the weaker patches of the ridge. The whole filament is composed of two opposite-direction streams, implying that longitudinal oscillations are not the only cause of the counterstreamings, and unidirectional siphon flows with alternative directions are another possibility.

  1. Potential formation in the plasma confinement region of a radio-frequency plugged linear device

    International Nuclear Information System (INIS)

    Fujita, Hideki; Kumazawa, Ryuhei; Howald, A.M.; Okamura, Shoichi; Sato, Teruyuki; Adati, Keizo; Garner, H.R.; Nishimura, Kiyohiko.

    1987-08-01

    Plasma potential formation in an open-ended plasma confinement system with RF plugging (the RFC-XX-M device) is investigated. The plasma potential in the central confinement region is measured with a heavy ion beam probe system and potentials at the RF plug section are measured with multi-grid energy analyzers. The measured plasma potential is compared with that deduced from the generalized Pastukhov formula. Results show that the plasma potential develops as an ambipolar potential to equate ion and electron end losses. During RF plugging, electrons are heated by Landau damping, while ions are not heated since adiabatic conditions apply during ion plugging in this experiment. (author)

  2. Analyzing the Implications of Climate Data on Plant Hardiness Zones for Green Infrastructure Planning: Case Study of Knoxville, Tennessee and Surrounding Region

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester, Linda M [ORNL; Omitaomu, Olufemi A [ORNL; Parish, Esther S [ORNL

    2016-07-01

    Downscaled climate data for Knoxville, Tennessee and the surrounding region were used to investigate future changing Plant Hardiness Zones due to climate change. The methodology used is the same as the US Department of Agriculture (USDA), well-known for their creation of the standard Plant Hardiness Zone map used by gardeners and planners. USDA data were calculated from observed daily data for 1976–2005. The modeled climate data for the past is daily data from 1980-2005 and the future data is projected for 2025–2050. The average of all the modeled annual extreme minimums for each time period of interest was calculated. Each 1 km raster cell was placed into zone categories based on temperature, using the same criteria and categories of the USDA. The individual models vary between suggesting little change to the Plant Hardiness Zones to suggesting Knoxville moves into the next two Hardiness Zones. But overall, the models suggest moving into the next warmer Zone. USDA currently has the Knoxville area categorized as Zone 7a. None of the Zones calculated from the climate data models placed Knoxville in Zone 7a for the similar time period. The models placed Knoxville in a cooler Hardiness Zone and projected the area to increase to Zone 7. The modeled temperature data appears to be slightly cooler than the actual temperature data and this may explain the zone discrepancy. However, overall Knoxville is projected to increase to the next warmer Zone. As the modeled data has Knoxville, overall, moving from Zone 6 to Zone 7, it can be inferred that Knoxville, Tennessee may increase from their current Zone 7 to Zone 8.

  3. Investigation of edge plasmas in the anchor cell region of GAMMA 10

    International Nuclear Information System (INIS)

    Islam, Khairul; Nakashima, Yousuke; Yatsu, Kiyoshi

    2000-01-01

    The first results of Langmuir probe measurements at the outer transition region of the anchor cell of GAMMA 10 are given. A probe current asymmetry in vertical direction is found in this region. It is also found that the asymmetry of probe current increases in outward direction and the direction of the asymmetry is independent on movable limiter position. A relation of the plasma asymmetry with the main magnetic field configuration is investigated. Plasma flow through the non-asymmetric magnetic field configuration region is thought to be the source of plasma asymmetry in this region, i.e., ∇B and curvature drifts are responsible for the asymmetry. Possibility of cold plasma formation in the anchor cell region is obtained during plug electron cyclotron resonance heating (ECRH) and can be explained with the desorption of particles due to the collision of the drifted out particles with the wall. (author)

  4. Plasma behaviors in the open field region of reversed-field theta-pinch

    International Nuclear Information System (INIS)

    Aso, Yoshiyuki; Hirano, Keiichi.

    1983-03-01

    A characteristic behavior of the plasma in an open field region of reversed field theta pinch has been studied with the guide field (GF) which extends the field line along the axial direction. The experimental result suggests that the rotaional instability may be induced in FRC after the plasma touches the wall at the ends of the open field. (author)

  5. Ethno-medicinal study of plants used for treatment of human ailments, with residents of the surrounding region of forest fragments of Paraná, Brazil.

    Science.gov (United States)

    Bolson, Mônica; Hefler, Sonia Marisa; Hefler, Sonia Regina; Dall'Oglio Chaves, Elisiane Inês; Gasparotto Junior, Arquimedes; Cardozo Junior, Euclides Lara

    2015-02-23

    This study aims to document the traditional knowledge on the use of medicinal plants in the neighborhood of the protected area "Parque Estadual da Cabeça do Cachorro", a fragment of seasonal semideciduous forests. This vegetation is intensely fragmented and disturbed; despite its importance there are few records of the traditional knowledge of medicinal species. Twenty-four residents in the neighborhood of the protected area "Parque Estadual da Cabeça do Cachorro" were interviewed. The residents were questioned about preparation techniques, recommended doses, ways of administration and healing properties of various parts of the plants and were invited to walk through the park to collect in situ some species of plants. The recognized medicinal species were identified and traditional knowledge was systematized. Quantitative indices (Informant Consensus Factor - FIC and Use Value - UV) were calculated. 115 species of medicinal plants belonging to 54 botanical families were cited. Asteraceae (n=14), Fabaceae (n=11), Myrtaceae (n=6), Bignoniaceae, Solanaceae and Verbenaceae (n=5) were the most species-rich. The highest use values were calculated for Achyrocline satureioides, Aristolochia triangularis and Bauhinia forficata (0.63). Moreover, the informants consensus about usages of medicinal plants ranges from 0.024 to 0.663, which shows high level of agreements among the informants for gastro-intestinal and respiratory system diseases. Furthermore, for the first time, new traditional medicinal uses of Asteraceae (Chromolaena pedunculosa Hook. & Arn.), Commelinaceae (Tradescantia fluminensis Vell.) and Polypodiaceae (Microgramma vacciniifolia Langsd. & Fisch.) species were reported. Present study revealed that the residents of the surrounding region of forest fragments of Paraná are rich in ethno-medicinal knowledge and rely on plant-based remedies for common health problems. As in many parts of Brazil knowledge of the past is combined with new knowledge that has

  6. Charging and trapping of macroparticles in near-electrode regions of fluorocarbon plasmas with negative ions

    International Nuclear Information System (INIS)

    Ostrikov, K.N.; Kumar, S.; Sugai, H.

    2001-01-01

    Charging and trapping of macroparticles in the near-electrode region of fluorocarbon etching plasmas with negative ions is considered. The equilibrium charge and forces on particles are computed as a function of the local position in the plasma presheath and sheath. The ionic composition of the plasma corresponds to the etching experiments in 2.45 GHz surface-wave sustained and 13.56 MHz inductively coupled C 4 F 8 +Ar plasmas. It is shown that despite negligible negative ion currents collected by the particles, the negative fluorine ions affect the charging and trapping of particulates through modification of the sheath/presheath structure

  7. Large plasma density enhancements occurring in the northern polar region during the 6 April 2000 superstorm

    Science.gov (United States)

    Horvath, Ildiko; Lovell, Brian C.

    2014-06-01

    We focus on the ionospheric response of northern high-latitude region to the 6 April 2000 superstorm and aim to investigate how the storm-enhanced density (SED) plume plasma became distributed in the regions of auroral zone and polar cap plus to study the resultant ionospheric features and their development. Multi-instrument observational results combined with model-generated, two-cell convection maps permitted identifying the high-density plasma's origin and the underlying plasma transportation processes. Results show the plasma density feature of polar cap enhancement (PCE; 600 × 103 i+/cm3) appearing for 7 h during the main phase and characterized by increases reaching up to 6 times of the quiet time values. Meanwhile, strong westward convections ( 17,500 m/s) created low plasma densities in a wider region of the dusk cell. Oppositely, small ( 750 m/s) but rigorous westward drifts drove the SED plume plasma through the auroral zone, wherein plasma densities doubled. As the SED plume plasma traveled along the convection streamlines and entered the polar cap, a continuous enhancement of the tongue of ionization (TOI) developed under steady convection conditions. However, convection changes caused slow convections and flow stagnations and thus segmented the TOI feature by locally depleting the plasma in the affected regions of the auroral zone and polar cap. From the strong correspondence of polar cap potential drop and subauroral polarization stream (SAPS), we conclude that the SAPS E-field strength remained strong, and under its prolonged influence, the SED plume provided a continuous supply of downward flowing high-density plasma for the development and maintenance of PCEs.

  8. Multi-instrument comparisons of D-region plasma measurements

    Directory of Open Access Journals (Sweden)

    M. Friedrich

    2013-01-01

    Full Text Available The ECOMA (Existence and Charge state Of Meteoric dust grains in the middle Atmosphere series of sounding rocket flights consisted of nine flights with almost identical payload design and flight characteristics. All flights carried a radio wave propagation experiment together with a variety of plasma probes. Three of these measured electron densities, two ion densities. The rockets were all launched from the Andøya Rocket Range, Norway, in four campaigns between 2006 and 2010. Emphasis is on the final three flights from 2010 where the payloads were equipped with four instruments capable of measuring plasma densities in situ, among them a novel probe flown for the first time in conjunction with a wave propagation experiment. Deviation factors of all probe data relative to the wave propagation results were derived and revealed that none of the probe data were close to the wave propagation results at all heights, but – more importantly – the instruments showed very different behaviour at different altitudes. The novel multi-needle Langmuir probe exhibits the best correlation to the wave propagation data, as there is minimal influence of the payload potential, but it is still subject to aerodynamics, especially at its location at the rear of the payload. For all other probe types, the deviation factor comes closer to unity with increasing plasma density. No systematic difference of the empirical deviation factor between day and night can be found. The large negative payload potential in the last three flights may be the cause for discrepancies between electron and ion probe data below 85 km.

  9. Spectral classification of medium-scale high-latitude F region plasma density irregularities

    International Nuclear Information System (INIS)

    Singh, M.; Rodriguez, P.; Szuszczewicz, E.P.; Sachs Freeman Associates, Bowie, MD)

    1985-01-01

    The high-latitude ionosphere represents a highly structured plasma. Rodriguez and Szuszczewicz (1984) reported a wide range of plasma density irregularities (150 km to 75 m) at high latitudes near 200 km. They have shown that the small-scale irregularities (7.5 km to 75 m) populated the dayside oval more often than the other phenomenological regions. It was suggested that in the lower F region the chemical recombination is fast enough to remove small-scale irregularities before convection can transport them large distances, leaving structured particle precipitation as the dominant source term for irregularities. The present paper provides the results of spectral analyses of pulsed plasma probe data collected in situ aboard the STP/S3-4 satellite during the period March-September 1978. A quantitative description of irregularity spectra in the high-latitude lower F region plasma density is given. 22 references

  10. Direct evidence of plasma - density structuring in the auroral F-region ionosphere

    International Nuclear Information System (INIS)

    Tsunoda, R.T.; Haeggstroem, I.; Pellinen-Wannberg, A.; Steen, Aa.; Wannberg, G.

    1985-03-01

    We investigate the hypothesis that large-scale plasma-density enhancements found in the auroral F layer become structured via a magnetic-flux-tube interchange (MFTI) process. In such a process, plasma structure is produced when spatially irregular electric fields transport higher number-density plasma into a region containing lower number-density plasma, and vice versa. Direct experimental evidence of this process can be obtained by measuring concurrently the spatial distributions of F-region plasma density and electric field. Using the tristatic EISCAT radar facility, we measured these quantities in a two-dimensional plane transverse to the geomagnetic field, at 300-km altitude. We show, in a case study, that plasma-density structure found along the poleward wall of a blob was indeed accompanied by similar-scale variations in the ionospheric electric field, and that the sense of relative motion between high- and low-number-density plasma is consistent with ongoing structuring of the plasma via a MFTI process. From the estimated growth rate of 3 x 10 -3 s -1 , the observed plasma structure could have been produced in several minutes by the irregular electic field pattern. The source of the MFTI process, however, is not clear. The MFTI process did not appear to be driven by F-region polarization electric fields, a conclusion based on (1) the apparent lack of inverse correlation between plasma density and 'slip' velocity patterns, and (2) the positive growth rate found along the poleward wall of the blob in the presence of a westward Pedersen current. This conclusion excludes (at least for this data set) the gradient-drift and current-convective instabilities as primary sources of the ongoing structuring process. (Author)

  11. Plasma polarization spectroscopy. Time resolved spectroscopy in soft x-ray region on recombining plasma

    International Nuclear Information System (INIS)

    Iwamae, Atsushi; Hasuo, Masahiro; Atake, Makoto; Hasegawa, Noboru; Kawachi, Tetsuya

    2007-01-01

    We present an experimental study of polarization of emission radiations from recombining plasmas generated by the interaction of 60 fs ultra-short laser pulses with a gas jet. Time-resolved spectroscopy with a temporal resolution of 5 ps with repetitive accumulation is used to follow the recombination time histories. (author)

  12. Ground-water hydrology and simulation of ground-water flow at Operable Unit 3 and surrounding region, U.S. Naval Air Station, Jacksonville, Florida

    Science.gov (United States)

    Davis, J.H.

    1998-01-01

    The Naval Air Station, Jacksonville (herein referred to as the Station), occupies 3,800 acres adjacent to the St. Johns River in Duval County, Florida. Operable Unit 3 (OU3) occupies 134 acres on the eastern side of the Station and has been used for industrial and commercial purposes since World War II. Ground water contaminated by chlorinated organic compounds has been detected in the surficial aquifer at OU3. The U.S. Navy and U.S. Geological Survey (USGS) conducted a cooperative hydrologic study to evaluate the potential for ground water discharge to the neighboring St. Johns River. A ground-water flow model, previously developed for the area, was recalibrated for use in this study. At the Station, the surficial aquifer is exposed at land surface and forms the uppermost permeable unit. The aquifer ranges in thickness from 30 to 100 feet and consists of unconsolidated silty sands interbedded with local beds of clay. The low-permeability clays of the Hawthorn Group form the base of the aquifer. The USGS previously conducted a ground-water investigation at the Station that included the development and calibration of a 1-layer regional ground-water flow model. For this investigation, the regional model was recalibrated using additional data collected after the original calibration. The recalibrated model was then used to establish the boundaries for a smaller subregional model roughly centered on OU3. Within the subregional model, the surficial aquifer is composed of distinct upper and intermediate layers. The upper layer extends from land surface to a depth of approximately 15 feet below sea level; the intermediate layer extends from the upper layer down to the top of the Hawthorn Group. In the northern and central parts of OU3, the upper and intermediate layers are separated by a low-permeability clay layer. Horizontal hydraulic conductivities in the upper layer, determined from aquifer tests, range from 0.19 to 3.8 feet per day. The horizontal hydraulic

  13. Plasma characteristics in the discharge region of a 20 A emission current hollow cathode

    Science.gov (United States)

    Mingming, SUN; Tianping, ZHANG; Xiaodong, WEN; Weilong, GUO; Jiayao, SONG

    2018-02-01

    Numerical calculation and fluid simulation methods were used to obtain the plasma characteristics in the discharge region of the LIPS-300 ion thruster’s 20 A emission current hollow cathode and to verify the structural design of the emitter. The results of the two methods indicated that the highest plasma density and electron temperature, which improved significantly in the orifice region, were located in the discharge region of the hollow cathode. The magnitude of plasma density was about 1021 m-3 in the emitter and orifice regions, as obtained by numerical calculations, but decreased exponentially in the plume region with the distance from the orifice exit. Meanwhile, compared to the emitter region, the electron temperature and current improved by about 36% in the orifice region. The hollow cathode performance test results were in good agreement with the numerical calculation results, which proved that that the structural design of the emitter and the orifice met the requirements of a 20 A emission current. The numerical calculation method can be used to estimate plasma characteristics in the preliminary design stage of hollow cathodes.

  14. Model for resonant plasma probe.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Johnson, William Arthur; Hebner, Gregory Albert; Jorgenson, Roy E.; Coats, Rebecca Sue

    2007-04-01

    This report constructs simple circuit models for a hairpin shaped resonant plasma probe. Effects of the plasma sheath region surrounding the wires making up the probe are determined. Electromagnetic simulations of the probe are compared to the circuit model results. The perturbing effects of the disc cavity in which the probe operates are also found.

  15. Experimental evidence of widespread regions of small-scale plasma irregularities in the magnetosphere

    International Nuclear Information System (INIS)

    Holmgren, G.; Kintner, P.M.

    1990-01-01

    Small-scale (≤ 1 km) plasma irregularities have previously been observed in situ from the E region to an altitude of 8,000 km. In this paper the authors report results from the Viking plasma wave experiments which extends the measurements of high-latitude irregularities in two ways: (1) they have acquired electron density fluctuation measurements up to an altitude of 13,500 km and (2) for the first time a measurement technique was used that made a phase velocity deduction possible from in situ measurements. The spacecraft was equipped with two spatially separated Langmuir probes, each with an ability to measure relative probe current fluctuations with frequencies from dc to about 400 Hz. Under certain assumptions the current fluctuations could be interpreted as relative plasma density fluctuations, δn e /n e . Data from this interferometric instrument has been used to infer the distribution and nature of plasma irregularities along Viking orbits. It is demonstrated that the interferometric technique offers great advantages compared to single point measurements in this kind of study. It is shown that the observed small-scale plasma irregularities are nondispersive and convecting with the background plasma. They exhibit a power law frequency spectrum as observed in the satellite reference frame. The spectral index varies with location. An attempt to map source regions by identifying regions of high power and shallow spectrums is made

  16. Effect of plasma instability on F region photoelectron distributions

    International Nuclear Information System (INIS)

    Bloomberg, H.W.

    1975-01-01

    Ionospheric suprathermal photoelectrons have relatively large cross sections for selected energies. In particular, electrons with energies of about 2.5 eV strongly excite nitrogen vibrational modes, while metastable states of oxygen are excited at about 5 eV. Thus an energy distribution based on chemical kinetic considerations give rise to a maximum at around 4 eV in the F region below 250 km. However, rocket experiments have shown that the expected peaks in the flux spectrum are relatively weak. This discrepancy is explained by the development of a linear instability leading to a wave-particle interaction. The linear mode is driven by the photoelectrons near the 4-eV maximum in the presence of a magnetic field. The effect is shown to be ineffective at sufficiently low altitudes, where collisionless theory fails. (auth)

  17. Effect of plasma instability on F region photoelectron distributions

    International Nuclear Information System (INIS)

    Bloomberg, H.W.

    1975-01-01

    Ionospheric suprathermal photoelectrons have relatively large cross sections for selected energies. In particular, electrons with energies of about 2.5 eV strongly excite nitrogen vibrational modes, while metastable states of oxygen are excited at about 5 eV. Thus an energy distribution based on chemical kinetic considerations gives rise to a maximum at around 4 eV in the F region below 250 km. However, rocket experiments have shown that the expected peaks in the flux spectrum are relatively weak. This discrepancy is explained by the development of a linear instability leading to a wave-particle interaction. the linear mode is driven by the photoelectrons near the 4-eV maximum in the presence of a magnetic field. The effect is shown to be ineffective at sufficiently low altitudes, where collisionless theory fails

  18. The Downshift of Electron Plasma Oscillations in the Electron Foreshock Region.

    Science.gov (United States)

    1984-10-10

    Ii D-Ai50 52 THE DOWNSHIFT OF ELECTRON PLASMA OSCILLATIONS IN THE i/1. ELECTRON FORESHOCK R.. (U) I0MM UNIV 10MM CITY DEPT OF PHYSICS AND ASTRONOMY 5...OSCILLATIONS 0 IN THE ELECTRON FORESHOCK REGION In by S. A. Fuselierl, D. A. Gurnett 1 , Ace NTI 0. and R. J. Fitzenreiter 2 DTI I ,3WERSflY o. 06UNDED ISAI...geleasel Ditibto Unlimited 02 1 16 U. of Iowa 84-21 THE DOWNSHIFT OF ELECTRON PLASMA OSCILLATIONSJ / IN THE ELECTRON FORESHOCK REGION t - by Z I S. A

  19. Scale size and life time of energy conversion regions observed by Cluster in the plasma sheet

    Directory of Open Access Journals (Sweden)

    M. Hamrin

    2009-11-01

    Full Text Available In this article, and in a companion paper by Hamrin et al. (2009 [Occurrence and location of concentrated load and generator regions observed by Cluster in the plasma sheet], we investigate localized energy conversion regions (ECRs in Earth's plasma sheet. From more than 80 Cluster plasma sheet crossings (660 h data at the altitude of about 15–20 RE in the summer and fall of 2001, we have identified 116 Concentrated Load Regions (CLRs and 35 Concentrated Generator Regions (CGRs. By examining variations in the power density, E·J, where E is the electric field and J is the current density obtained by Cluster, we have estimated typical values of the scale size and life time of the CLRs and the CGRs. We find that a majority of the observed ECRs are rather stationary in space, but varying in time. Assuming that the ECRs are cylindrically shaped and equal in size, we conclude that the typical scale size of the ECRs is 2 RE≲ΔSECR≲5 RE. The ECRs hence occupy a significant portion of the mid altitude plasma sheet. Moreover, the CLRs appear to be somewhat larger than the CGRs. The life time of the ECRs are of the order of 1–10 min, consistent with the large scale magnetotail MHD simulations of Birn and Hesse (2005. The life time of the CGRs is somewhat shorter than for the CLRs. On time scales of 1–10 min, we believe that ECRs rise and vanish in significant regions of the plasma sheet, possibly oscillating between load and generator character. It is probable that at least some of the observed ECRs oscillate energy back and forth in the plasma sheet instead of channeling it to the ionosphere.

  20. Properties of the Plasma Surrounding the Global Heliosphere Determined with Voyager 1&2 ions and ENA/INCA Observations at E > 5 keV

    Science.gov (United States)

    Krimigis, S. M.; Dialynas, K.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2016-12-01

    The basic goal of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (5.2-55 keV) since 2003 and IBEX (0.3-6 keV) since 2009. The partial overlap in energies (28 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) Based on the ENA-derived hot ion pressures, the interstellar magnetic field (ISMF) was predicted to be more than twice that expected in the literature i.e. similar to what was measured by V1 after crossing the heliopause (B 0.5 nT). (3) The width of the HS in the direction of V1 is 30 AU (predicted by INCA before the V1 HP crossing), but is thought to be larger (40-70 AU) in the southern ecliptic where V2, now 30 AU into the HS, currently travels. We address here the key question of the source of 5-55 keV ENAs that INCA measures. The analysis of INCA all-sky maps from 2003 to 2014 show that the decrease and recovery of ENA in the global heliosphere during this period (declining phase of SC23 and rise of SC24) is similar to that of the ions at V1/V2, consistent with the HS ions being the source of ENA. The close correspondence between ENA and ion spectra (despite the 140 AU distance between V1 and V2) as well as the similarity of ENA spectra over the nose and anti-nose directions, together with the recent V1 measurement of a BISMF 0.5nT, suggest that the global distributions of >5 keV ions in the heliosheath resembles a diamagnetic bubble with no significant tail-like feature (the alternative Parker 1961 model), also consistent with some recent MHD simulations and models.

  1. Nonlinear Right-Hand Polarized Wave in Plasma in the Electron Cyclotron Resonance Region

    Science.gov (United States)

    Krasovitskiy, V. B.; Turikov, V. A.

    2018-05-01

    The propagation of a nonlinear right-hand polarized wave along an external magnetic field in subcritical plasma in the electron cyclotron resonance region is studied using numerical simulations. It is shown that a small-amplitude plasma wave excited in low-density plasma is unstable against modulation instability with a modulation period equal to the wavelength of the excited wave. The modulation amplitude in this case increases with decreasing detuning from the resonance frequency. The simulations have shown that, for large-amplitude waves of the laser frequency range propagating in plasma in a superstrong magnetic field, the maximum amplitude of the excited longitudinal electric field increases with the increasing external magnetic field and can reach 30% of the initial amplitude of the electric field in the laser wave. In this case, the energy of plasma electrons begins to substantially increase already at magnetic fields significantly lower than the resonance value. The laser energy transferred to plasma electrons in a strong external magnetic field is found to increase severalfold compared to that in isotropic plasma. It is shown that this mechanism of laser radiation absorption depends only slightly on the electron temperature.

  2. Transition Region Emission and the Energy Input to Thermal Plasma in Solar Flares

    Science.gov (United States)

    Holman, Gordon D.; Holman, Gordon D.; Dennis, Brian R.; Haga, Leah; Raymond, John C.; Panasyuk, Alexander

    2005-01-01

    Understanding the energetics of solar flares depends on obtaining reliable determinations of the energy input to flare plasma. X-ray observations of the thermal bremsstrahlung from hot flare plasma provide temperatures and emission measures which, along with estimates of the plasma volume, allow the energy content of this hot plasma to be computed. However, if thermal energy losses are significant or if significant energy goes directly into cooler plasma, this is only a lower limit on the total energy injected into thermal plasma during the flare. We use SOHO UVCS observations of O VI flare emission scattered by coronal O VI ions to deduce the flare emission at transition region temperatures between 100,000 K and 1 MK for the 2002 July 23 and other flares. We find that the radiated energy at these temperatures significantly increases the deduced energy input to the thermal plasma, but by an amount that is less than the uncertainty in the computed energies. Comparisons of computed thermal and nonthermal electron energies deduced from RHESSI, GOES, and UVCS are shown.

  3. A preliminary comparison of F region plasma drifts and E region irregularity drifts in the auroral zone

    International Nuclear Information System (INIS)

    Ecklund, W.L.; Balsley, B.B.; Carter, D.A.

    1977-01-01

    During several days in April--May 1976 the Chatanika, Alaska, incoherent scatter radar and a temporary Doppler auroral radar located at Aniak, Alaska, were directed toward ionospheric volumes along a common magnetic field line in order to compare E region and F region drifts and associated electric fields. The Chatanika radar measured F region plasma drifts via the incoherent scatter technique, while the Aniak radar measured the drifts of E region irregularities (i.e., the radar aurora). The radar geometry was arranged so that both radars measured approximately the same velocity component of a magnetically westward or eastward motion. Preliminary data show good agreement between the drift velocity components measured by the two techniques during most of the experimental period. This result indicates that relatively modest auroral radar systems may be used, with some qualifications, to determine auroral electric fields

  4. Plasma currents and anisotropy in the tail-dipole transition region

    Science.gov (United States)

    Artemyev, A.; Zhang, X. J.; Angelopoulos, V.; Runov, A.

    2017-12-01

    Using conjugated THEMIS and Van Allen Probes observations in the nightside magnetosphere, we examine statistically plasma and magnetic field characteristics at multiple locations simultaneously across the 3-10 RE region (i.e., across the tail-dipole transition region, whose location depends on tail flux loading and the strength of global convection). We find that the spatial distributions of ion and electron anisotropies vary significantly but systematically with radial distance and geomagnetic activity. For low Kp (4), the anisotropy profiles for ions and electrons reverse: ions are isotropic closer to the Earth and field-aligned in the tail, whereas electrons are transversely anisotropic closer to Earth but isotropic in the tail. Using the measured plasma anisotropy radial profiles we estimate the currents from curvature drifts and compare them with diamagnetic currents. We also discuss the implications of the observed plasma anisotropies for the presence and spatial distribution of field-aligned electric fields.

  5. Equatorial F-region plasma depletion drifts: latitudinal and seasonal variations

    Directory of Open Access Journals (Sweden)

    A. A. Pimenta

    2003-12-01

    Full Text Available The equatorial ionospheric irregularities have been observed in the past few years by different techniques (e.g. ground-based radar, digisonde, GPS, optical instruments, in situ satellite and rocket instrumentation, and its time evolution and propagation characteristics can be used to study important aspects of ionospheric dynamics and thermosphere-ionosphere coupling. At present, one of the most powerful optical techniques to study the large-scale ionospheric irregularities is the all-sky imaging photometer system, which normally measures the strong F-region nightglow 630 nm emission from atomic oxygen. The monochromatic OI 630 nm emission images usually show quasi-north-south magnetic field-aligned intensity depletion bands, which are the bottomside optical signatures of large-scale F-region plasma irregularities (also called plasma bubbles. The zonal drift velocities of the plasma bubbles can be inferred from the space-time displacement of the dark structures (low intensity regions seen on the images. In this study, images obtained with an all-sky imaging photometer, using the OI 630 nm nightglow emission, from Cachoeira Paulista (22.7° S, 45° W, 15.8° S dip latitude, Brazil, have been used to determine the nocturnal monthly and latitudinal variation characteristics of the zonal plasma bubble drift velocities in the low latitude (16.7° S to 28.7° S region. The east and west walls of the plasma bubble show a different evolution with time. The method used here is based on the western wall of the bubble, which presents a more stable behavior. Also, the observed zonal plasma bubble drift velocities are compared with the thermospheric zonal neutral wind velocities obtained from the HWM-90 model (Hedin et al., 1991 to investigate the thermosphere-ionosphere coupling. Salient features from this study are presented and discussed.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric irregularities; instruments and techniques

  6. Occurrence and location of concentrated load and generator regions observed by Cluster in the plasma sheet

    Directory of Open Access Journals (Sweden)

    M. Hamrin

    2009-11-01

    Full Text Available Here, and in a companion paper by Hamrin et al. (2009 [Scale size and life time of energy conversion regions observed by Cluster in the plasma sheet], we investigate localized energy conversion regions (ECRs in the Earth's plasma sheet. In total we have studied 151 ECRs within 660 h of plasma sheet data from the summer and fall of 2001 when Cluster was close to apogee at an altitude of about 15–20 RE. Cluster offers appropriate conditions for the investigation of energy conversion by the evaluation of the power density, E·J, where E is the electric field and J the current density. From the sign of the power density, we have identified more than three times as many Concentrated Load Regions (CLRs as Concentrated Generator Regions (CGRs. We also note that the CLRs appear to be stronger. To our knowledge, these are the first in situ observations confirming the general notion of the plasma sheet, on the average, behaving as a load. At the same time the plasma sheet appears to be highly structured, with energy conversion occurring in both directions between the fields and the particles. From our data we also find that the CLRs appear to be located closer to the neutral sheet, while CGRs prefer locations towards the plasma sheet boundary layer (PSBL. For both CLRs and CGRs, E and J in the GSM y (cross-tail direction dominate the total power density, even though the z contribution occasionally can be significant. The prevalence of the y-direction seems to be weaker for the CGRs, possibly related to a higher fluctuation level near the PSBL.

  7. Effects of photoirradiation in UV and VUV regions during plasma exposure to polymers

    International Nuclear Information System (INIS)

    Cho, Ken; Setsuhara, Yuichi; Takenaka, Kosuke; Shiratani, Masaharu; Sekine, Makoto; Hori, Masaru

    2011-01-01

    Interactions between photons irradiated from Ar-O 2 mixture plasmas and polymer surfaces were investigated on the basis of depth analyses of chemical bonding states in the nano-surface layer of polyethylene terephthalate (PET) films via hard X-ray photoelectron spectroscopy (HXPES) and conventional X-ray photoelectron spectroscopy (XPS). The PET films were exposed to photons from the Ar-O 2 mixture plasmas by covering the PET samples with MgF 2 and quartz windows as optical filters for evaluation of photoirradiation effects in ultraviolet (UV) and vacuum ultraviolet (VUV) regions. The HXPES results indicated that the degradation of the chemical bonding states due to photoirradiation in regions was insignificant in deeper regions up to about 50 nm from the surface. Whereas, conventional XPS analysis showed that C-O bond, O=C-O bond and C=O bond increased after photoirradiation in UV and VUV regions. These results suggest that the increase in oxygen functionalities (C-O bond, O=C-O bond and C=O bond) may be attributed to chemical reactions and/or terminations of scissed bonds via photodecompositions of the polymer with oxygen and/or OH species (oxygen molecules and radicals during plasma exposure and/or oxygen molecules and moisture after taking the PET samples out of the plasma reactor to the ambient air) in the vicinity of the sample surface.

  8. Regional differences in the lateral mobility of plasma membrane lipids in a molluscan embryo

    NARCIS (Netherlands)

    Speksnijder, J.E.; Dohmen, M.R.; Tertoolen, L.G.J.; Laat, S.W. de

    1985-01-01

    Regional and temporal differences in plasma membrane lipid mobility have been analyzed during the first three cleavage cycles of the embryo of the polar-lobe-forming mollusc Nassarius reticulatus by the fluorescence photobleaching recovery (FPR) method, using 1,1′-ditetradecyl

  9. Facies Analysis of Tertiary Basin-Filling Rocks of the Death Valley Regional Ground-Water System and Surrounding Areas, Nevada and California; TOPICAL

    International Nuclear Information System (INIS)

    Sweetkind, D.S.; Fridrich, C.J.; Taylor, Emily

    2002-01-01

    Existing hydrologic models of the Death Valley region typically have defined the Cenozoic basins as those areas that are covered by recent surficial deposits, and have treated the basin-fill deposits that are concealed under alluvium as a single unit with uniform hydrologic properties throughout the region, and with depth. Although this latter generalization was known to be flawed, it evidently was made because available geologic syntheses did not provide the basis for a more detailed characterization. As an initial attempt to address this problem, this report presents a compilation and synthesis of existing and new surface and subsurface data on the lithologic variations between and within the Cenozoic basin fills of this region. The most permeable lithologies in the Cenozoic basin fills are freshwater limestones, unaltered densely welded tuffs, and little-consolidated coarse alluvium. The least permeable lithologies are playa claystones, altered nonwelded tuffs, and tuffaceous and cl ay-matrix sediments of several types. In all but the youngest of the basin fills, permeability probably decreases strongly with depth owing to a typically increasing abundance of volcanic ash or clay in the matrices of the clastic sediments with increasing age (and therefore with increasing depth in general), and to increasing consolidation and alteration (both hydrothermal and diagenetic) with increasing depth and age. This report concludes with a categorization of the Cenozoic basins of the Death Valley region according to the predominant lithologies in the different basin fills and presents qualitative constraints on the hydrologic properties of these major lithologic categories

  10. Difference in chemical reactions in bulk plasma and sheath regions during surface modification of graphene oxide film using capacitively coupled NH{sub 3} plasma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung-Youp; Kim, Chan; Kim, Hong Tak, E-mail: zam89blue@gmail.com [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2015-09-14

    Reduced graphene oxide (r-GO) films were obtained from capacitively coupled NH{sub 3} plasma treatment of spin-coated graphene oxide (GO) films at room temperature. Variations were evaluated according to the two plasma treatment regions: the bulk plasma region (R{sub bulk}) and the sheath region (R{sub sheath}). Reduction and nitridation of the GO films began as soon as the NH{sub 3} plasma was exposed to both regions. However, with the increase in treatment time, the reduction and nitridation reactions differed in each region. In the R{sub bulk}, NH{sub 3} plasma ions reacted chemically with oxygen functional groups on the GO films, which was highly effective for reduction and nitridation. While in the R{sub sheath}, physical reactions by ion bombardment were dominant because plasma ions were accelerated by the strong electrical field. The accelerated plasma ions reacted not only with the oxygen functional groups but also with the broken carbon chains, which caused the removal of the GO films by the formation of hydrocarbon gas species. These results showed that reduction and nitridation in the R{sub bulk} using capacitively coupled NH{sub 3} plasma were very effective for modifying the properties of r-GO films for application as transparent conductive films.

  11. Effects of a conducting E layer on classical F region cross-field plasma diffusion

    International Nuclear Information System (INIS)

    Vickrey, J.F.; Kelley, M.C.

    1982-01-01

    The rate of cross-field plasma diffusion in the F region ionosphere is significantly increased when the magnetic field lines thread a highly conducting E region below. This reduces the lifetime of small-scale F region electron density irregularities in the polar ionosphere where the presence of a highly conducting E region is comonplace. A simple mmodel is developed to describe the effects of a conducting E layer on classical F region plasma diffusion. In the absence of an E region, the difference in ion and electron diffusion rates leads to a charge separation and, hence, to an electrostatic field that retards ion diffusion. When the highly conducting magnetic field lines are tied to a conducting E region, however, electrons can flow along B to reduce the ambipolar diffusion electric field, and ions can proceed perpendicular to B at a rate approaching their own (higher) diffusion velocity. It is shown that the enhanced total diffusion rate that results depends strongly on the height of the F layer and on the ratio of the E to F region Pedersen conductivities

  12. Pioneer 7 observations of plasma flow and field reversal regions in the distant geomagnetic tail

    International Nuclear Information System (INIS)

    Walker, R.C.; Villante, U.; Lazarus, A.J.

    1975-01-01

    We present the results of an extensive analysis of plasma and magnetic field data from Pioneer 7 taken in the geomagnetic tail approximately 1000 R/sub E/ downstream from earth. The principal observations are (1) measurable fluxes of protons in the tail, flowing away from earth, sometimes with a double-peaked velocity distribution; (2) field reversal regions in which the field changes from radial to antiradial by a vector rotation in the north-south plane; and (3) general characteristics of the tail similar to those observed near earth with good correlation between taillike magnetic fields and plasma

  13. Pioneer 7 observations of plasma flow and field reversal regions in the distant geomagnetic tail

    Science.gov (United States)

    Walker, R. C.; Lazarus, A. J.; Villante, U.

    1975-01-01

    The present paper gives the results of an extensive analysis of plasma and magnetic-field data from Pioneer 7 taken in the geomagnetic tail approximately 1000 earth radii downstream from earth. The principal observations are: (1) measurable fluxes of protons in the tail, flowing away from earth, sometimes with a double-peaked velocity distribution; (2) field reversal regions in which the field changes from radial to antiradial by a vector rotation in the north-south plane; and (3) general characteristics of the tail similar to those observed near earth with good correlation between taillike magnetic fields and plasma.

  14. Assessing the environmental fate of selected polybrominated diphenyl ethers in the region surrounding the Zhuoshui River of Taiwan based on an Equilibrium Constant fugacity model

    Science.gov (United States)

    O'Driscoll, Kieran; Doherty, Rory; Robinson, Jill; Chiang, Wen-Son; Kao Kao, Ruey-Chy

    2015-04-01

    Polybrominated diphenyl ethers (PBDEs) are a group of flame retardants that have been in use since the 1970s. They are included in the list of hazardous substances known as persistent organic pollutants (POPs) because they are extremely hazardous to the environment and human health. PBDEs have been extensively used in industry and manufacturing in Taiwan, thus its citizens are at high risk of exposure to these chemicals. An assessment of the environmental fate of these compounds in the Zhuoshui river and Changhua County regions of western Taiwan, and also including the adjacent area of the Taiwan Strait, was conducted for three high risk congeners, BDE-47, -99 and -209, to obtain information regarding the partitioning, advection, transfer and long range transport potential of the PBDEs in order to identify the level of risk posed by the pollutants in this region. The results indicate that large amounts of PBDEs presently reside in all model compartments - air, soil, water, and sediment - with particularly high levels found in air and especially in sediment. The high levels found in sediment, particularly for BDE-209, are significant, since there is the threat of these pollutants entering the food chain, either directly through benthic feeding, or through resuspension and subsequent feeding in the pelagic region of the water column which is a distinct possibility in the strong currents found within the Taiwan Strait. Another important result is that a substantial portion of emissions leave the model domain directly through advection, particularly for BDE-47 (58%) and BDE-209 (75%), thus posing a risk to adjacent communities. Model results were generally in reasonable agreement with available measured concentrations. In air, model concentrations are in reasonably good agreement with available measured values. For both BDE-47 and -99, model concentrations are a factor of 2-3 higher and BDE-209 within the range of measured values. In soil, model results are somewhat

  15. Regional magnetic and gravity surveys: an aid for uranium exploration - case study from Renigunta and surrounding areas, Chitoor district, Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Narasimha Rao, B.; Rama Krishna, P.; Markandeyulu, A.; Dwivedy, K.K.

    1998-01-01

    Regional magnetic and gravity data of Papanaidupet area, Chitoor district, are discussed in the light of bore hole information for selection of target areas for uranium exploration. The low-pass filtered magnetic data shows a 'smooth' picture suppressing the high frequency components in the original data. The amplitude maxima of analytic signal outline the magnetic source at depth. The Bouguer gravity residual anomaly corresponding to a double sill-like model beneath is used to explain the borehole intercepts, after petro-physical studies of the borehole samples. (author)

  16. Assessment of metals pollution on agricultural soil surrounding a lead-zinc mining area in the Karst region of Guangxi, China.

    Science.gov (United States)

    Zhang, Chaolan; Li, Zhongyi; Yang, Weiwei; Pan, Liping; Gu, Minghua; Lee, DoKyoung

    2013-06-01

    Soil samples were collected on farmland in a lead-zinc mining area in the Karst region of Guangxi, China. The contamination of the soil by eight metals (Cd, Hg, As, Cu, Pb, Cr, Zn, Ni) was determined. Among all these metals, Cd is the most serious pollutant in this area. Zn, Hg as well asPb can also be measured at high levels, which may affect the crop production. All other metals contributed marginally to the overall soil contamination. Besides the evaluation of single metals, the Nemerow synthetic index indicated that the soil is not suitable for agricultural use.

  17. Thermal equilibrium of pure electron plasmas across a central region of magnetic surfaces

    Science.gov (United States)

    Hahn, Michael; Pedersen, Thomas Sunn

    2009-06-01

    Measurements of the equilibria of plasmas created by emission from a biased filament located off the magnetic axis in the Columbia Non-neutral Torus (CNT) [T. S. Pedersen, J. P. Kremer, R. G. Lefrancois et al., Fusion Sci. Technol. 50, 372 (2006)] show that such plasmas have equilibrium properties consistent with the inner surfaces being in a state of cross-surface thermal equilibrium. Numerical solutions to the equilibrium equation were used to fit the experimental data and demonstrate consistency with cross-surface thermal equilibrium. Previous experiments in CNT showed that constant temperatures across magnetic surfaces are characteristic of CNT plasmas, implying thermal confinement times much less than particle confinement times. These results show that when emitting off axis there is a volume of inner surfaces where diffusion into that region is balanced by outward transport, producing a Boltzmann distribution of electrons. When combined with the low thermal energy confinement time this is a cross-surface thermal equilibrium.

  18. Thermal equilibrium of pure electron plasmas across a central region of magnetic surfaces

    International Nuclear Information System (INIS)

    Hahn, Michael; Pedersen, Thomas Sunn

    2009-01-01

    Measurements of the equilibria of plasmas created by emission from a biased filament located off the magnetic axis in the Columbia Non-neutral Torus (CNT) [T. S. Pedersen, J. P. Kremer, R. G. Lefrancois et al., Fusion Sci. Technol. 50, 372 (2006)] show that such plasmas have equilibrium properties consistent with the inner surfaces being in a state of cross-surface thermal equilibrium. Numerical solutions to the equilibrium equation were used to fit the experimental data and demonstrate consistency with cross-surface thermal equilibrium. Previous experiments in CNT showed that constant temperatures across magnetic surfaces are characteristic of CNT plasmas, implying thermal confinement times much less than particle confinement times. These results show that when emitting off axis there is a volume of inner surfaces where diffusion into that region is balanced by outward transport, producing a Boltzmann distribution of electrons. When combined with the low thermal energy confinement time this is a cross-surface thermal equilibrium.

  19. Modelling of ion thermal transport in ergodic region of collisionless toroidal plasma

    International Nuclear Information System (INIS)

    Kanno, Ryutaro; Nunami, Masanori; Satake, Shinsuke; Ohyabu, Nobuyoshi; Takamaru, Hisanori; Okamoto, Masao

    2009-09-01

    In recent tokamak experiments it has been found that so-called diffusion theory based on the 'diffusion of magnetic field lines' overestimates the radial energy transport in the ergodic region of the collisionless plasma affected by resonant magnetic perturbations (RMPs), though the RMPs induce chaotic behavior of the magnetic field lines. The result implies that the modelling of the transport should be reconsidered for low collisionality cases. A computer simulation study of transport in the ergodic region is required for understanding fundamental properties of collisionless ergodized-plasmas, estimating the transport coefficients, and reconstructing the modelling of the transport. In this paper, we report the simulation study of thermal transport in the ergodic region under the assumption of neglecting effects of an electric field, impurities and neutrals. Because of the simulations neglecting interactions with different particle-species and saving the computational time, we treat ions (protons) in our numerical-study of the transport. We find that the thermal diffusivity in the ergodic region is extremely small compared to the one predicted by the theory of field-line diffusion and that the diffusivity depends on both the collision frequency and the strength of RMPs even for the collisionless ergodized-plasma. (author)

  20. TWO-DIMENSIONAL CELLULAR AUTOMATON MODEL FOR THE EVOLUTION OF ACTIVE REGION CORONAL PLASMAS

    Energy Technology Data Exchange (ETDEWEB)

    López Fuentes, Marcelo [Instituto de Astronomía y Física del Espacio, CONICET-UBA, CC. 67, Suc. 28, 1428 Buenos Aires (Argentina); Klimchuk, James A., E-mail: lopezf@iafe.uba.ar [NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States)

    2015-02-01

    We study a two-dimensional cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their footpoints by photospheric motions. The magnetic stress accumulated between neighbor strands is released in sudden reconnection events or nanoflares that heat the plasma. We combine the CA model with the Enthalpy Based Thermal Evolution of Loops model to compute the response of the plasma to the heating events. Using the known response of the X-Ray Telescope on board Hinode, we also obtain synthetic data. The model obeys easy-to-understand scaling laws relating the output (nanoflare energy, temperature, density, intensity) to the input parameters (field strength, strand length, critical misalignment angle). The nanoflares have a power-law distribution with a universal slope of –2.5, independent of the input parameters. The repetition frequency of nanoflares, expressed in terms of the plasma cooling time, increases with strand length. We discuss the implications of our results for the problem of heating and evolution of active region coronal plasmas.

  1. Opportunity's Surroundings on Sol 1818

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,818th Martian day, or sol, of Opportunity's surface mission (March 5, 2009). South is at the center; north at both ends. The rover had driven 80.3 meters (263 feet) southward earlier on that sol. Tracks from the drive recede northward in this view. The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  2. Effect of steroid on brain tumors and surround edemas : observation with regional cerebral blood volume (rCBV) maps of perfusion MRI

    International Nuclear Information System (INIS)

    Choi, Ju Youl; Sun, Joo Sung; Kim, Sun Yong; Kim, Ji Hyung; Suh, Jung Ho; Cho, Kyung Gi; Kim, Jang Sung

    2000-01-01

    To observe the hemodynamic change in brain tumors and peritumoral edemas after steroid treatment, and then investigate the clinical usefulness of perfusion MRI. We acquired conventional and perfusion MR images in 15 patients with various intracranial tumors (4 glioblastoma multiformes, 4 meningiomas, 3 metastatic tumors, 1 anaplastic ependymoma, 1 anaplastic astrocytoma, 1 hemangioblastoma, and 1 pilocytic astrocytoma). For perfusion MR imaging, a 1.5T unit employing the gradient-echo EPI technique was used, and further perfusion MR images were obtained 2-10 days after intravenous steroid therapy. After processing of the raw data, regional cerebral blood volume (rCBV) maps were reconstructed. The maps were visually evaluated by comparing relative perfusion in brain tumors and peritumoral edemas with that in contralateral white matter. Objective evaluations were performed by comparing the perfusion ratios of brain tumors and peritumoral edemas. Visual evaluations of rCBV maps, showed that in most brain tumors (67%, 10/15), perfusion was high before steroid treatment and showed in (80%, 12/15) decreased afterwards. Objective evaluation, showed that in all brain tumors, perfusion decreased. Visual evaluation of perfusion change in peritumoral edemas revealed change in only one case, but objective evaluation indicated that perfusion decreased significantly in all seven cases. rCBV maps acquired by perfusion MR imaging can provide hemodynamic information about brain tumors and peritumoral edemas. Such maps could prove helpful in the preoperative planning of brain tumor surgery and the monitoring of steroid effects during conservative treatment. (author)

  3. Effects of Chernobyl on Mittelfranken. An evaluation of Erlangen and the surrounding regions. Auswirkungen von 'Tschernobyl' auf Mittelfranken. Bewertung am Beispiel Erlangen und Umgebung

    Energy Technology Data Exchange (ETDEWEB)

    Deubner, S; Iwatschenko-Borho, M; Malzer, S; Plank, H; Schmitzer, R; Giesse, E; Baurichter, A; Heer, G; Kleffner, B; Pfister, H

    1986-01-01

    According to an analysis of radioactivity in the atmosphere, ground, plants and meat Mittelfranken values are as follows: 1) The dispersion of ground pollution values by far exceeds that of other regions in Bavaria. 2) Dairy milk was constantly keeping a rough 10% below the iodine 131 limiting value. Drinking water remained unpolluted. 3) From the beginning to the middle of May vegetables such as spinach and the like, potherbs as well as pollen and honey were generally showing values above the iodine and cesium limiting values. 4) The beginning of July was showing small fruits (about 250 Bq/kg cesium 137 and 134) and venison (about 600 Bq/kg cesium) to be still contaminated considerably. 5) The contamination of sand boxes proved to be negligible compared with other sources. 6) The contamination and risk of breathing highly active 'hot particles' cannot be evaluated definitely. 7) The high concentration of long-lived radioactive substances in sewage sludges requires the sludges to be carefully analyzed before they are made available for manuring purposes. 8) According to estimations cesium is assumed to be one of the major factors to be made responsible for a long-term contamination of foods.

  4. Factors Affecting Elevated Arsenic and Methyl Mercury Concentrations in Small Shield Lakes Surrounding Gold Mines near the Yellowknife, NT, (Canada Region.

    Directory of Open Access Journals (Sweden)

    Adam James Houben

    Full Text Available Gold mines in the Yellowknife, NT, region--in particular, the Giant Mine--operated from 1949-99, releasing 237,000 tonnes of waste arsenic trioxide (As2O3 dust, among other compounds, from gold ore extraction and roasting processes. For the first time, we show the geospatial distribution of roaster-derived emissions of several chemical species beyond the mine property on otherwise undisturbed taiga shield lakes within a 25 km radius of the mine, 11 years after its closing. Additionally, we demonstrate that underlying bedrock is not a significant source for the elevated concentrations in overlying surface waters. Aquatic arsenic (As concentrations are well above guidelines for drinking water (10 μg/L and protection for aquatic life (5 μg/L, ranging up to 136 μg/L in lakes within 4 km from the mine, to 2.0 μg/L in lakes 24 km away. High conversion ratios of methyl mercury were shown in lakes near the roaster stack as well, with MeHg concentrations reaching 44% of total mercury. The risk of elevated exposures by these metals is significant, as many lakes used for recreation and fishing near the City of Yellowknife are within this radius of elevated As and methyl Hg concentrations.

  5. Scale size and life time of energy conversion regions observed by Cluster in the plasma sheet

    Directory of Open Access Journals (Sweden)

    M. Hamrin

    2009-11-01

    Full Text Available In this article, and in a companion paper by Hamrin et al. (2009 [Occurrence and location of concentrated load and generator regions observed by Cluster in the plasma sheet], we investigate localized energy conversion regions (ECRs in Earth's plasma sheet. From more than 80 Cluster plasma sheet crossings (660 h data at the altitude of about 15–20 RE in the summer and fall of 2001, we have identified 116 Concentrated Load Regions (CLRs and 35 Concentrated Generator Regions (CGRs. By examining variations in the power density, E·J, where E is the electric field and J is the current density obtained by Cluster, we have estimated typical values of the scale size and life time of the CLRs and the CGRs. We find that a majority of the observed ECRs are rather stationary in space, but varying in time. Assuming that the ECRs are cylindrically shaped and equal in size, we conclude that the typical scale size of the ECRs is 2 RE≲ΔSECR≲5 RE. The ECRs hence occupy a significant portion of the mid altitude plasma sheet. Moreover, the CLRs appear to be somewhat larger than the CGRs. The life time of the ECRs are of the order of 1–10 min, consistent with the large scale magnetotail MHD simulations of Birn and Hesse (2005. The life time of the CGRs is somewhat shorter than for the CLRs. On time scales of 1–10 min, we believe that ECRs rise and vanish in significant regions of the plasma sheet, possibly oscillating between load and generator character. It is probable that at least some of the observed ECRs oscillate energy back and forth in the plasma sheet instead of channeling it to the ionosphere.

  6. Twined plasma produced by powered double probe in the tail region

    International Nuclear Information System (INIS)

    Minami, Sigeyuki; Takeya, Yoshio; Hirose, Yoshiaki.

    1977-01-01

    Simulation experiments have been operated by some workers in order to make clear the behavior of plasma in the magnetosphere. The large-scales surveys of the upper atmosphere with the use of satellite were not done in those days, so this simulated magnetospheric experiments in the laboratory was watched. These early experiments were done in order to know the structure of the shock front and its time variation at the front of the earth which was generated by the interaction of the high speed plasma flow and magnetic dipole, and also to know the magnetic field distribution in the solar cusp near the shock front. At this paper, the results obtained by optical method for the behavior and the structures in the region at tail of the magnetosphere are dealed. In order to know the tail region, active power source of named powered double probe is used. (auth.)

  7. A fully kinetic, self-consistent particle simulation model of the collisionless plasma--sheath region

    International Nuclear Information System (INIS)

    Procassini, R.J.; Birdsall, C.K.; Morse, E.C.

    1990-01-01

    A fully kinetic particle-in-cell (PIC) model is used to self-consistently determine the steady-state potential profile in a collisionless plasma that contacts a floating, absorbing boundary. To balance the flow of particles to the wall, a distributed source region is used to inject particles into the one-dimensional system. The effect of the particle source distribution function on the source region and collector sheath potential drops, and particle velocity distributions is investigated. The ion source functions proposed by Emmert et al. [Phys. Fluids 23, 803 (1980)] and Bissell and Johnson [Phys. Fluids 30, 779 (1987)] (and various combinations of these) are used for the injection of both ions and electrons. The values of the potential drops obtained from the PIC simulations are compared to those from the theories of Emmert et al., Bissell and Johnson, and Scheuer and Emmert [Phys. Fluids 31, 3645 (1988)], all of which assume that the electron density is related to the plasma potential via the Boltzmann relation. The values of the source region and total potential drop are found to depend on the choice of the electron source function, as well as the ion source function. The question of an infinite electric field at the plasma--sheath interface, which arises in the analyses of Bissell and Johnson and Scheuer and Emmert, is also addressed

  8. Equatorial F-region plasma depletion drifts: latitudinal and seasonal variations

    Directory of Open Access Journals (Sweden)

    A. A. Pimenta

    Full Text Available The equatorial ionospheric irregularities have been observed in the past few years by different techniques (e.g. ground-based radar, digisonde, GPS, optical instruments, in situ satellite and rocket instrumentation, and its time evolution and propagation characteristics can be used to study important aspects of ionospheric dynamics and thermosphere-ionosphere coupling. At present, one of the most powerful optical techniques to study the large-scale ionospheric irregularities is the all-sky imaging photometer system, which normally measures the strong F-region nightglow 630 nm emission from atomic oxygen. The monochromatic OI 630 nm emission images usually show quasi-north-south magnetic field-aligned intensity depletion bands, which are the bottomside optical signatures of large-scale F-region plasma irregularities (also called plasma bubbles. The zonal drift velocities of the plasma bubbles can be inferred from the space-time displacement of the dark structures (low intensity regions seen on the images. In this study, images obtained with an all-sky imaging photometer, using the OI 630 nm nightglow emission, from Cachoeira Paulista (22.7° S, 45° W, 15.8° S dip latitude, Brazil, have been used to determine the nocturnal monthly and latitudinal variation characteristics of the zonal plasma bubble drift velocities in the low latitude (16.7° S to 28.7° S region. The east and west walls of the plasma bubble show a different evolution with time. The method used here is based on the western wall of the bubble, which presents a more stable behavior. Also, the observed zonal plasma bubble drift velocities are compared with the thermospheric zonal neutral wind velocities obtained from the HWM-90 model (Hedin et al., 1991 to investigate the thermosphere-ionosphere coupling. Salient features from this study are presented

  9. Plasma Irregularity Production in the Polar Cap F-Region Ionosphere

    Science.gov (United States)

    Lamarche, Leslie

    Plasma in the Earth's ionosphere is highly irregular on scales ranging between a few centimeters and hundreds of kilometers. Small-scale irregularities or plasma waves can scatter radio waves resulting in a loss of signal for navigation and communication networks. The polar region is particularly susceptible to strong disturbances due to its direct connection with the Sun's magnetic field and energetic particles. In this thesis, factors that contribute to the production of decameter-scale plasma irregularities in the polar F region ionosphere are investigated. Both global and local control of irregularity production are studied, i.e. we consider global solar control through solar illumination and solar wind as well as much more local control by plasma density gradients and convection electric field. In the first experimental study, solar control of irregularity production is investigated using the Super Dual Auroral Radar Network (SuperDARN) radar at McMurdo, Antarctica. The occurrence trends for irregularities are analyzed statistically and a model is developed that describes the location of radar echoes within the radar's field-of-view. The trends are explained through variations in background plasma density with solar illumination affecting radar beam propagation. However, it is found that the irregularity occurrence during the night is higher than expected from ray tracing simulations based on a standard ionospheric density model. The high occurrence at night implies an additional source of plasma density and it is proposed that large-scale density enhancements called polar patches may be the source of this density. Additionally, occurrence maximizes around the terminator due to different competing irregularity production processes that favor a more or less sunlit ionosphere. The second study is concerned with modeling irregularity characteristics near a large-scale density gradient reversal, such as those expected near polar patches, with a particular focus on

  10. Spectrograms of the JT-60 plasmas in the vacuum ultraviolet region (wavelength region 15 ∼ 1360 A)

    International Nuclear Information System (INIS)

    Kubo, Hirotaka; Sugie, Tatsuo; Sakasai, Akira; Koide, Yoshihiko; Nishino, Nobuhiro; Akaoka, Nobuo

    1988-07-01

    Spectrograms in the vacuum ultraviolet region have been obtained by a 3 m grazing incidence spectrograph in order to study impurity behaviors in JT-60 plasma. The spectrograms have been investigated in the first OH experiments, High-Ti mode experiments, and the experiments that were carried out after the replacement of 40 % of the first wall of the vacuum vessel with graphite tiles. In the first OH experiments, the spectrogram which covered the wavelength region of 15 ∼ 1360 A was obtained, and spectral lines of oxygen, carbon, and titanium were identified. In High-Ti mode experiments, the spectrogram which covered the wavelength region of 17 ∼ 77 A was obtained, and spectral lines of highly ionized molybdenum were identified in addition to those of oxygen, carbon, and titanium. In the experiments after the replacement of the first wall, the spectrogram which covered the wavelength region of 15 ∼ 55 A was obtained, and it was found clearly that the metallic impurities decreased. (author)

  11. The equatorial E-region and its plasma instabilities: a tutorial

    Directory of Open Access Journals (Sweden)

    D. T. Farley

    2009-04-01

    Full Text Available In this short tutorial we first briefly review the basic physics of the E-region of the equatorial ionosphere, with emphasis on the strong electrojet current system that drives plasma instabilities and generates strong plasma waves that are easily detected by radars and rocket probes. We then discuss the instabilities themselves, both the theory and some examples of the observational data. These instabilities have now been studied for about half a century (!, beginning with the IGY, particularly at the Jicamarca Radio Observatory in Peru. The linear fluid theory of the important processes is now well understood, but there are still questions about some kinetic effects, not to mention the considerable amount of work to be done before we have a full quantitative understanding of the limiting nonlinear processes that determine the details of what we actually observe. As our observational techniques, especially the radar techniques, improve, we find some answers, but also more and more questions. One difficulty with studying natural phenomena, such as these instabilities, is that we cannot perform active cause-and-effect experiments; we are limited to the inputs and responses that nature provides. The one hope here is the steadily growing capability of numerical plasma simulations. If we can accurately simulate the relevant plasma physics, we can control the inputs and measure the responses in great detail. Unfortunately, the problem is inherently three-dimensional, and we still need somewhat more computer power than is currently available, although we have come a long way.

  12. Electrostatic fluxes and plasma rotation in the edge region of EXTRAP-T2R

    International Nuclear Information System (INIS)

    Serianni, G.; Antoni, V.; Bergsaaker, H.; Brunsell, P.; Drake, J.R.; Spolaore, M.; Saetherblom, H.E.; Vianello, N.

    2001-01-01

    The EXTRAP-T2 reversed field pinch has undergone a significant reconstruction into the new T2R device. This paper reports the first measurements performed with Langmuir probes in the edge region of EXTRAP-T2R. The radial profiles of plasma parameters like electron density and temperature, plasma potential, electrical fields and electrostatic turbulence-driven particle flux are presented. These profiles are interpreted in a momentum balance model where finite Larmor radius losses occur over a distance of about two Larmor radii from the limiter position. The double shear layer of the ExB drift velocity is discussed in terms of the Biglari-Diamond-Terry theory of turbulence decorrelation. (author)

  13. Electrostatic Fluxes and Plasma Rotation in the Edge Region of EXTRAP-T2R

    Science.gov (United States)

    Serianni, G.; Antoni, V.; Bergsåker, H.; Brunsell, P.; Drake, J. R.; Spolaore, M.; Sätherblom, H. E.; Vianello, N.

    2001-10-01

    The EXTRAP-T2 reversed field pinch has undergone a significant reconstruction into the new T2R device. This paper reports the first measurements performed with Langmuir probes in the edge region of EXTRAP-T2R. The radial profiles of plasma parameters like electron density and temperature, plasma potential, electrical fields and electrostatic turbulence-driven particle flux are presented. These profiles are interpreted in a momentum balance model where finite Larmor radius losses occur over a distance of about two Larmor radii from the limiter position. The double shear layer of the E×B drift velocity is discussed in terms of the Biglari-Diamond-Terry theory of turbulence decorrelation.

  14. HOT PLASMA FROM SOLAR ACTIVE-REGION CORES: CONSTRAINTS FROM THE HINODE X-RAY TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Schmelz, J. T. [USRA, 7178 Columbia Gateway Drive, Columbia, MD 21046 (United States); Christian, G. M.; Matheny, P. O., E-mail: jschmelz@usra.edu [Physics Department, University of Memphis, Memphis, TN 38152 (United States)

    2016-12-20

    Mechanisms invoked to heat the solar corona to millions of degrees kelvin involve either magnetic waves or magnetic reconnections. Turbulence in the convection zone produces MHD waves, which travel upward and dissipate. Photospheric motions continuously build up magnetic energy, which is released through magnetic reconnection. In this paper, we concentrate on hot non-flaring plasma with temperatures of 5 MK <  T  < 10 MK because it is one of the few observables for which wave and reconnection models make different predictions. Wave models predict no (or little) hot plasma, whereas reconnection models predict it, although in amounts that are challenging to detect with current instrumentation. We used data from the X-ray Telescope (XRT) and the Atmospheric Imaging Assembly (AIA). We requested a special XRT observing sequence, which cycled through the thickest XRT filter several times per hour so we could average these images and improve the signal-to-noise. We did differential emission measure (DEM) analysis using the time-averaged thick-filter data as well as all available channels from both the XRT and AIA for regions observed on 2014 December 11. Whereas our earlier work was only able to determine that plasma with a temperature greater than 5 MK was present , we are now able to find a well-constrained DEM distribution. We have therefore added a strong observational constraint that must be explained by any viable coronal heating model. Comparing state-of-the-art wave and reconnection model predictions, we can conclude that reconnection is heating the hot plasma in these active regions.

  15. Lateral mobility of plasma membrane lipids in Xenopus eggs: Regional differences related to animal/vegetal polarity

    NARCIS (Netherlands)

    Laat, S.W. de; Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van; Tetteroo, P.A.T.; Tertoolen, L.G.J.

    1984-01-01

    Regional differences in the lateral mobility properties of plasma membrane lipids were studied in unfertilized and fertilized Xenopus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein- -1abelled fatty

  16. Lateral Organization of Influenza Virus Proteins in the Budozone Region of the Plasma Membrane.

    Science.gov (United States)

    Leser, George P; Lamb, Robert A

    2017-05-01

    between viral proteins in the plasma membrane. Some proteins, such as HA and M2, inherently cocluster within the membrane, although M2 is found mostly at the periphery of regions of HA, consistent with the proposed role of M2 in scission at the end of budding. The association between some pairs of influenza virus proteins, such as M2 and NP, appears to be brokered by additional influenza virus proteins, in this case M1. HA and NA, while raft associated, reside in distinct domains, reflecting their distributions in the viral membrane. Copyright © 2017 American Society for Microbiology.

  17. Numerical Modeling of the Work Piece Region in the Plasma Arc Cutting Process

    Science.gov (United States)

    Osterhouse, David

    The plasma arc cutting process is widely used for the cutting of metals. The process, however, is not fully understood and further understanding will lead to further improvements. This work aims to elucidate the fundamental physical phenomena in the region where the plasma interacts with the work piece through the use of numerical modeling techniques. This model follows standard computational fluid dynamic methods that have been suitably modified to include plasma effects, assuming either local thermodynamic equilibrium or a slight non-equilibrium captured by the two-temperature assumption. This is implemented in the general purpose, open source CFD package, OpenFOAM. The model is applied to a plasma flow through a geometry that extends from inside the plasma torch to the bottom of the slot cut in the work piece. The shape of the kerf is taken from experimental measurements. The results of this model include the temperature, velocity, and electrical current distribution throughout the plasma. From this, the heat flux to and drag force on the work piece are calculated. The location of the arc attachment in the cut slot is also noted because it is a matter of interest in the published literature as well as significantly effecting the dynamics of the heat flux and drag force. The results of this model show that the LTE formulation is not sufficient to capture the physics present due to unphysical fluid dynamic instabilities and numerical problems with the arc attachment. The two-temperature formulation, however, captures a large part of the physics present. Of particular note, it is found that an additional inelastic collision factor is necessary to describe the increased energy transfer between electrons and diatomic molecules, which is widely neglected in published literature. It is also found that inclusion of the oxygen molecular ion is necessary to accurately describe the plasma flow, which has been neglected in all published two-temperature oxygen calculations

  18. Auroral E-region diagnosis by means of nonlinearly stabilized plasma waves

    International Nuclear Information System (INIS)

    Primdahl, F.; Bahnsen, A.

    1985-01-01

    Recently published comparative measurements indicate that the phase velocity of low frequency waves in the ionospheric E-region is often lower than the drift speed of the electrons that drive the waves unstable. This finding is in agreement with a rocket experiment that measured plasma waves ''in situ''. These data are reevaluated in the present paper. In order to understand these results, the linear instability theory is modified, following Sudan, to conform with zero growth rate even above threshold. The result is that the waves travel at the ion-acoustic velocity with an amplitude stabilized at a level which is found to agree with our observations

  19. Regional differences in the lateral mobility of plasma membrane lipids in a molluscan embryo

    OpenAIRE

    Speksnijder, J.E.; Dohmen, M.R.; Tertoolen, L.G.J.; Laat, S.W. de

    1985-01-01

    Regional and temporal differences in plasma membrane lipid mobility have been analyzed during the first three cleavage cycles of the embryo of the polar-lobe-forming mollusc Nassarius reticulatus by the fluorescence photobleaching recovery (FPR) method, using 1,1′-ditetradecyl 3,3,3′,3′-tetramethylindocarbocyanine iodide (C14diI) as a fluorescent lipid probe. During this period of development the lateral diffusion coefficient of membrane lipids is consistently greater in the vegetal polar lob...

  20. Evidence of stochastic region near a rational surface in core plasmas of LHD

    International Nuclear Information System (INIS)

    Ida, K.; Tamura, N.; Tuchiya, H.

    2010-11-01

    Clear evidence of stochastization of the magnetic surfaces near a rational surface is observed in the core plasma with weak magnetic shear in the Large Helical Device (LHD) by applying heat pulses driven by modulated electron cyclotron heating (MECH). The stochastization of the magnetic surfaces is confirmed by the observation of flattening of electron temperature (T e ) profiles and very fast propagation of the heat pulse, which is in contrast to the slow heat pulse propagation observed in the T e flat region of the nested magnetic island. (author)

  1. Opportunity's Surroundings on Sol 1798

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 180-degree view of the rover's surroundings during the 1,798th Martian day, or sol, of Opportunity's surface mission (Feb. 13, 2009). North is on top. The rover had driven 111 meters (364 feet) southward on the preceding sol. Tracks from that drive recede northward in this view. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  2. Effect of magnetic activity on plasma bubbles over equatorial and low-latitude regions in East Asia

    Directory of Open Access Journals (Sweden)

    G. Li

    2009-01-01

    Full Text Available The dependence of plasma bubble occurrence in the eveningside ionosphere, with magnetic activity during the period years 2001–2004, is studied here based on the TEC observations gathered by ground-based GPS receivers which are located in the equatorial and low-latitude regions in East Asia. The observed plasma bubbles consist of the plasma-bubble events in the equatorial (stations GUAM, PIMO and KAYT, and low-latitude regions (stations WUHN, DAEJ and SHAO. It is shown that most equatorial plasma-bubble events commence at 20:00 LT, and may last for >60 min. The magnetic activity appears to suppress the generation of equatorial plasma bubbles with a time delay of more than 3 h (4–9 h. While in the low-latitude regions, most plasma-bubble events commence at about 23:00 LT and last for <45 min. The best correlation between Kp and low-latitude plasma-bubble occurrence is found with an 8–9 h delay, a weak correlation exists for time delays of 6–7 h. This probably indicates that over 3 h delayed disturbance dynamo electric fields obviously inhibit the development of plasma bubbles in the pre-midnight sector.

  3. Opportunities for Utilizing the International Space Station for Studies of F2- Region Plasma Science and High Voltage Solar Array Interactions with the Plasma Environment

    Science.gov (United States)

    Minow, Joseph I.; Coffey, Victoria; Wright, Kenneth; Craven, Paul; Koontz, Steven

    2010-01-01

    The near circular, 51.6deg inclination orbit of the International Space Station (ISS) is maintained within an altitude range of approximately 300 km to 400 km providing an ideal platform for conducting in-situ studies of space weather effects on the mid and low-latitude F-2 region ionosphere. The Floating Potential Measurement Unit (FPMU) is a suite of instruments installed on the ISS in August 2006 which includes a Floating Potential Probe (FPP), a Plasma Impedance Probe (PIP), a Wide-sweep Langmuir Probe (WLP), and a Narrow-sweep Langmuir Probe (NLP). The primary purpose for deploying the FPMU is to characterize ambient plasma temperatures and densities in which the ISS operates and to obtain measurements of the ISS potential relative to the space plasma environment for use in characterizing and mitigating spacecraft charging hazards to the vehicle and crew. In addition to the engineering goals, data from the FPMU instrument package is available for collaborative multi-satellite and ground based instrument studies of the F-region ionosphere during both quiet and disturbed periods. Finally, the FPMU measurements supported by ISS engineering telemetry data provides a unique opportunity to investigate interactions of the ISS high voltage (160 volt) solar array system with the plasma environment. This presentation will provide examples of FPMU measurements along the ISS orbit including night-time equatorial plasma density depletions sampled near the peak electron density in the F2-region ionosphere, charging phenomenon due to interaction of the ISS solar arrays with the plasma environment, and modification of ISS charging due to visiting vehicles demonstrating the capabilities of the FPMU probes for monitoring mid and low latitude plasma processes as well as vehicle interactions with the plasma environment.

  4. Regional amino acid transport into brain during diabetes: Effect of plasma amino acids

    International Nuclear Information System (INIS)

    Mans, A.M.; DeJoseph, M.R.; Davis, D.W.; Hawkins, R.A.

    1987-01-01

    Transport of phenylalanine and lysine into the brain was measured in 4-wk streptozotocin-diabetic rats to assess the effect on the neutral and basic amino acid transport systems at the blood-brain barrier. Amino acid concentrations in plasma and brain were also measured. Regional permeability-times-surface area (PS) products and influx were determined using a continuous infusion method and quantitative autoradiography. The PS of phenylalanine was decreased by an average of 40% throughout the entire brain. Influx was depressed by 35%. The PS of lysine was increased by an average of 44%, but the influx was decreased by 27%. Several plasma neutral amino acids (branched chain) were increased, whereas all basic amino acids were decreased. Brain tryptophan, phenylalanine, tyrosine, methionine, and lysine contents were markedly decreased. The transport changes were almost entirely accounted for by the alterations in the concentrations of the plasma amino acids that compete for the neutral and basic amino acid carriers. The reduced influx could be responsible for the low brain content of some essential amino acids, with possibly deleterious consequences for brain functions

  5. Numerical analysis of electronegative plasma in the extraction region of negative hydrogen ion sources

    Science.gov (United States)

    Kuppel, S.; Matsushita, D.; Hatayama, A.; Bacal, M.

    2011-01-01

    This numerical study focuses on the physical mechanisms involved in the extraction of volume-produced H- ions from a steady state laboratory negative hydrogen ion source with one opening in the plasma electrode (PE) on which a dc-bias voltage is applied. A weak magnetic field is applied in the source plasma transversely to the extracted beam. The goal is to highlight the combined effects of the weak magnetic field and the PE bias voltage (upon the extraction process of H- ions and electrons). To do so, we focus on the behavior of electrons and volume-produced negative ions within a two-dimensional model using the particle-in-cell method. No collision processes are taken into account, except for electron diffusion across the magnetic field using a simple random-walk model at each time step of the simulation. The results show first that applying the magnetic field (without PE bias) enhances H- ion extraction, while it drastically decreases the extracted electron current. Secondly, the extracted H- ion current has a maximum when the PE bias is equal to the plasma potential, while the extracted electron current is significantly reduced by applying the PE bias. The underlying mechanism leading to the above results is the gradual opening by the PE bias of the equipotential lines towards the parts of the extraction region facing the PE. The shape of these lines is due originally to the electron trapping by the magnetic field.

  6. Numerical analysis of electronegative plasma in the extraction region of negative hydrogen ion sources

    International Nuclear Information System (INIS)

    Kuppel, S.; Matsushita, D.; Hatayama, A.; Bacal, M.

    2011-01-01

    This numerical study focuses on the physical mechanisms involved in the extraction of volume-produced H - ions from a steady state laboratory negative hydrogen ion source with one opening in the plasma electrode (PE) on which a dc-bias voltage is applied. A weak magnetic field is applied in the source plasma transversely to the extracted beam. The goal is to highlight the combined effects of the weak magnetic field and the PE bias voltage (upon the extraction process of H - ions and electrons). To do so, we focus on the behavior of electrons and volume-produced negative ions within a two-dimensional model using the particle-in-cell method. No collision processes are taken into account, except for electron diffusion across the magnetic field using a simple random-walk model at each time step of the simulation. The results show first that applying the magnetic field (without PE bias) enhances H - ion extraction, while it drastically decreases the extracted electron current. Secondly, the extracted H - ion current has a maximum when the PE bias is equal to the plasma potential, while the extracted electron current is significantly reduced by applying the PE bias. The underlying mechanism leading to the above results is the gradual opening by the PE bias of the equipotential lines towards the parts of the extraction region facing the PE. The shape of these lines is due originally to the electron trapping by the magnetic field.

  7. Characteristics of laser produced plasmas of hafnium and tantalum in the 1-7 nm region

    Science.gov (United States)

    Li, Bowen; Otsuka, Takamitsu; Sokell, Emma; Dunne, Padraig; O'Sullivan, Gerry; Hara, Hiroyuki; Arai, Goki; Tamura, Toshiki; Ono, Yuichi; Dinh, Thanh-Hung; Higashiguchi, Takeshi

    2017-11-01

    Soft X-ray (SXR) spectra from hafnium and tantalum laser produced plasmas were recorded in the 1-7 nm region using two Nd:YAG lasers with pulse lengths of 170 ps and 10 ns, respectively, operating at a range of power densities. The maximum focused peak power density was 2. 3 × 1014 W cm-2 for 170 ps pulses and 1. 8 × 1012 W cm-2 for 10 ns pulses, respectively. Two intense quasicontinuous intensity bands resulting from n = 4 - n = 4 and n = 4 - n = 5 unresolved transition arrays (UTAs) dominate both sets of experimental spectra. Comparison with calculations performed with the Cowan suite of atomic structure codes as well as consideration of previous experimental and theoretical results aided identification of the most prominent features in the spectra. For the 10 ns spectrum, the highest ion stage that could be identified from the n = 4 - n = 5 arrays were lower than silver-like Hf25+ and Ta26+ (which has a 4 d 104 f ground configuration) indicating that the plasma temperature attained was too low to produce ions with an outermost 4 d subshell, while for the 170 ps plasmas the presence of significantly higher stages was deduced and lines due to 4 d-5 p transitions were clearly evident. Furthermore, we show an enhancement of emission from tantalum using dual laser irradiation, and the effect of pre-pulse durations and delay times between two pulses are demonstrated.

  8. Correlation of Coronal Plasma Properties and Solar Magnetic Field in a Decaying Active Region

    Science.gov (United States)

    Ko, Yuan-Kuen; Young, Peter R.; Muglach, Karin; Warren, Harry P.; Ugarte-Urra, Ignacio

    2016-01-01

    We present the analysis of a decaying active region observed by the EUV Imaging Spectrometer on Hinode during 2009 December 7-11. We investigated the temporal evolution of its structure exhibited by plasma at temperatures from 300,000 to 2.8 million degrees, and derived the electron density, differential emission measure, effective electron temperature, and elemental abundance ratios of Si/S and Fe/S (as a measure of the First Ionization Potential (FIP) Effect). We compared these coronal properties to the temporal evolution of the photospheric magnetic field strength obtained from the Solar and Heliospheric Observatory Michelson Doppler Imager magnetograms. We find that, while these coronal properties all decreased with time during this decay phase, the largest change was at plasma above 1.5 million degrees. The photospheric magnetic field strength also decreased with time but mainly for field strengths lower than about 70 Gauss. The effective electron temperature and the FIP bias seem to reach a basal state (at 1.5 x 10(exp 6) K and 1.5, respectively) into the quiet Sun when the mean photospheric magnetic field (excluding all areas correlated with each other and the correlation is the strongest in the high-temperature plasma. Such correlation properties should be considered in the quest for our understanding of how the corona is heated. The variations in the elemental abundance should especially be considered together with the electron temperature and density.

  9. Regional differences in the lateral mobility of plasma membrane lipids in a molluscan embryo.

    Science.gov (United States)

    Speksnijder, J E; Dohmen, M R; Tertoolen, L G; de Laat, S W

    1985-07-01

    Regional and temporal differences in plasma membrane lipid mobility have been analyzed during the first three cleavage cycles of the embryo of the polar-lobe-forming mollusc Nassarius reticulatus by the fluorescence photobleaching recovery (FPR) method, using 1,1'-ditetradecyl 3,3,3',3'-tetramethylindocarbocyanine iodide (C14diI) as a fluorescent lipid probe. During this period of development the lateral diffusion coefficient of membrane lipids is consistently greater in the vegetal polar lobe area as compared to the animal plasma membrane area (on average 30%), demonstrating the existence of an animal-vegetal polarity in plasma membrane properties. At third cleavage, the differences between animal and vegetal plasma membrane region become even more pronounced; in the four animal micromeres the diffusion coefficient (D) and mobile fraction (MF) are 2.9 +/- 0.2 X 10(-9) cm2/sec and 51 +/- 2%, respectively, while in the four vegetal macromeres D = 5.0 +/- 0.3 X 10(-9) cm2/sec and MF = 78 +/- 2%. Superimposed upon the observed animal-vegetal polarity, the lateral diffusion in the polar lobe membrane area shows a cell-cycle-dependent modulation. The highest mean values for D are reached during the S phase (ranging from 7.0 to 7.8 X 10(-9) cm2/sec in the three cycles measured), while at the end of G2 phase and during early mitosis mean values for D have decreased significantly (ranging from 5.0 to 5.9 X 10(-9) cm2/sec). Diffusion rates in the animal membranes of the embryo are constant during the three successive cell cycles (D = 4.3-5.0 X 10(-9) cm2/sec), except for a peak at the S phase of the first cell cycle (D = 6.0 X 10(-9) cm2/sec). These results are discussed in relation with previously observed ultrastructural heterogeneities in the Nassarius egg plasma membrane. It is speculated that the observed animal-vegetal polarity in the organization of the egg membrane might play an important role in the process of cell diversification during early development.

  10. Changes in plasma cytokines and their soluble receptors in complex regional pain syndrome.

    Science.gov (United States)

    Alexander, Guillermo M; Peterlin, B Lee; Perreault, Marielle J; Grothusen, John R; Schwartzman, Robert J

    2012-01-01

    Complex Regional Pain Syndrome (CRPS) is a chronic and often disabling pain disorder. There is evidence demonstrating that neurogenic inflammation and activation of the immune system play a significant role in the pathophysiology of CRPS. This study evaluated the plasma levels of cytokines, chemokines, and their soluble receptors in 148 subjects afflicted with CRPS and in 60 gender- and age-matched healthy controls. Significant changes in plasma cytokines, chemokines, and their soluble receptors were found in subjects with CRPS as compared with healthy controls. For most analytes, these changes resulted from a distinct subset of the CRPS subjects. When the plasma data from the CRPS subjects was subjected to cluster analysis, it revealed 2 clusters within the CRPS population. The category identified as most important for cluster separation by the clustering algorithm was TNFα. Cluster 1 consisted of 64% of CRPS subjects and demonstrated analyte values similar to the healthy control individuals. Cluster 2 consisted of 36% of the CRPS subjects and demonstrated significantly elevated levels of most analytes and in addition, it showed that the increased plasma analyte levels in this cluster were correlated with disease duration and severity. The identification of biomarkers that define disease subgroups can be of great value in the design of specific therapies and of great benefit to the design of clinical trials. It may also aid in advancing our understanding of the mechanisms involved in the pathophysiology of CRPS, which may lead to novel treatments for this very severe condition. Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.

  11. A study of x-ray emission from the anode region in a plasma focus device

    International Nuclear Information System (INIS)

    Jia Wang; Tsinchi Yang

    1988-01-01

    The physical process of x-ray emission from the anode region in a plasma focus device due to the interaction of a powerful electron beam with the metal anode and with ionised metallic vapour from the anode is investigated. The influence of the magnetic field of the beam is taken into consideration. A MC-PIC model (Monte Carlo-particle in cell) is proposed for the process, in which an electron-photon collision cascade is simulated by the MC approach and the time-dependent state of metallic vapour is determined by PIC computation. The time-resolved energy spectra and angular distributions of x-ray emission from the extending anode region are calculated. The time-integrated characteristics of the x-ray emission can be compared with the results of experiments as far as they are available. (author)

  12. Relationship between ionospheric plasma bubble occurrence and lightning strikes over the Amazon region

    Directory of Open Access Journals (Sweden)

    J. Sousasantos

    2018-03-01

    Full Text Available The vertical coupling between the troposphere and the ionosphere presents some remarkable features. Under intense tropospheric convection, gravity waves may be generated, and once they reach the ionosphere, these waves may seed instabilities and spread F and equatorial plasma bubble events may take place. Additionally, there is a close association between severe tropospheric convection and lightning strikes. In this work an investigation covering an equinox period (September–October during the deep solar minimum (2009 presents the relation between lightning strike activity and spread F (equatorial plasma bubble detected over a low-latitude Brazilian region. The results show a considerable correlation between these two phenomena. The common element in the center of this conformity seems to be the gravity waves. Once gravity waves and lightning strikes share the same source (intense tropospheric convection and the effects of such gravity waves in the ionosphere include the seeding of instabilities according to the gravity waves magnitude, the monitoring of the lightning strike activity seems to offer some information about the subsequent development of spread F over the equatorial region.

  13. Relationship between ionospheric plasma bubble occurrence and lightning strikes over the Amazon region

    Science.gov (United States)

    Sousasantos, Jonas; Sobral, José Humberto Andrade; Alam Kherani, Esfhan; Magalhães Fares Saba, Marcelo; Rodolfo de Campos, Diovane

    2018-03-01

    The vertical coupling between the troposphere and the ionosphere presents some remarkable features. Under intense tropospheric convection, gravity waves may be generated, and once they reach the ionosphere, these waves may seed instabilities and spread F and equatorial plasma bubble events may take place. Additionally, there is a close association between severe tropospheric convection and lightning strikes. In this work an investigation covering an equinox period (September-October) during the deep solar minimum (2009) presents the relation between lightning strike activity and spread F (equatorial plasma bubble) detected over a low-latitude Brazilian region. The results show a considerable correlation between these two phenomena. The common element in the center of this conformity seems to be the gravity waves. Once gravity waves and lightning strikes share the same source (intense tropospheric convection) and the effects of such gravity waves in the ionosphere include the seeding of instabilities according to the gravity waves magnitude, the monitoring of the lightning strike activity seems to offer some information about the subsequent development of spread F over the equatorial region.

  14. PREFACE: Light element atom, molecule and radical behaviour in the divertor and edge plasma regions

    Science.gov (United States)

    Braams, Bastiaan J.; Chung, Hyun-Kung

    2015-01-01

    This volume of Journal of Physics: Conference Series contains contributions by participants in an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on "Light element atom, molecule and radical behaviour in the divertor and edge plasma regions" (in magnetic fusion devices). Light elements are the dominant impurity species in fusion experiments and in the near-wall plasma they occur as atoms or ions and also as hydrides and other molecules and molecular ions. Hydrogen (H or D, and T in a reactor) is the dominant species in fusion experiments, but all light elements He - O and Ne are of interest for various reasons. Helium is a product of the D+T fusion reaction and is introduced in experiments for transport studies. Lithium is used for wall coating and also as a beam diagnostic material. Beryllium is foreseen as a wall material for the ITER experiment and is used on the Joint European Torus (JET) experiment. Boron may be used as a coating material for the vessel walls. Carbon (graphite or carbon-fiber composite) is often used as the target material for wall regions subject to high heat load. Nitrogen may be used as a buffer gas for edge plasma cooling. Oxygen is a common impurity in experiments due to residual water vapor. Finally, neon is another choice as a buffer gas. Data for collisional and radiative processes involving these species are important for plasma modelling and for diagnostics. The participants in the CRP met 3 times over the years 2009-2013 for a research coordination meeting. Reports and presentation materials for these meetings are available through the web page on coordinated research projects of the (IAEA) Atomic and Molecular Data Unit [1]. Some of the numerical data generated in the course of the CRP is available through the ALADDIN database [2]. The IAEA takes the opportunity to thank the participants in the CRP for their dedicated efforts in the course of the CRP and for their contributions to this volume. The IAEA

  15. Radiation from an equilibrium CO2-N2 plasma in the [250-850 nm] spectral region: II. Spectral modelling

    International Nuclear Information System (INIS)

    Silva, M Lino da; Vacher, D; Andre, P; Faure, G; Dudeck, M

    2008-01-01

    In the first part of this work, described in a previous paper, the thermodynamic conditions in an atmospheric pressure inductively coupled CO 2 -N 2 plasma have been determined, and the radiation emission spectrum has been measured and calibrated in the [250-850 nm] spectral region. In the second part of this work, a synthetic radiation spectrum is obtained taking into account (a) the geometry of the plasma torch and (b) the local thermodynamic conditions of the plasma. This synthetic spectrum has then been compared against the measured spectrum. The good agreement between the two spectra allows validating the spectral database of the line-by-line code SPARTAN for the simulation of the radiative emission of CO 2 -N 2 plasmas from the near-UV to the near-IR spectral region.

  16. Correlation of Coronal Plasma Properties and Solar Magnetic Field in a Decaying Active Region

    Science.gov (United States)

    Ko, Yuan-Kuen; Young, Peter R.; Muglach, Karin; Warren, Harry P.; Ugarte-Urra, Ignacio

    2016-01-01

    We present the analysis of a decaying active region observed by the EUV Imaging Spectrometer on Hinode during 2009 December 7-11. We investigated the temporal evolution of its structure exhibited by plasma at temperatures from 300,000 to 2.8 million degrees, and derived the electron density, differential emission measure, effective electron temperature, and elemental abundance ratios of Si/S and Fe/S (as a measure of the First Ionization Potential (FIP) Effect). We compared these coronal properties to the temporal evolution of the photospheric magnetic field strength obtained from the Solar and Heliospheric Observatory Michelson Doppler Imager magnetograms. We find that, while these coronal properties all decreased with time during this decay phase, the largest change was at plasma above 1.5 million degrees. The photospheric magnetic field strength also decreased with time but mainly for field strengths lower than about 70 Gauss. The effective electron temperature and the FIP bias seem to reach a basal state (at 1.5 x 10(exp 6) K and 1.5, respectively) into the quiet Sun when the mean photospheric magnetic field (excluding all areas <10 G) weakened to below 35 G, while the electron density continued to decrease with the weakening field. These physical properties are all positively correlated with each other and the correlation is the strongest in the high-temperature plasma. Such correlation properties should be considered in the quest for our understanding of how the corona is heated. The variations in the elemental abundance should especially be considered together with the electron temperature and density.

  17. Upstream region, foreshock and bow shock wave at Halley's Comet from plasma electron measurements

    International Nuclear Information System (INIS)

    Anderson, K.A.; Carlson, C.W.; Curtis, D.W.

    1986-01-01

    Halley plasma electron parameters from 2.7 million km from the comet nucleus to the bow shock wave at 1.1 million km and beyond are surveyed. The features of the electron foreshock lying outside the shock to a distance of 230,000 km are described. It is a region of intense solar wind-comet plasma interaction in which energetic electrons are prominent. Several spikes of electrons whose energies extend to 2.5 keV appear in front of the shock. These energetic electrons may be accelerated in the same way electrons are accelerated at the Earth's bow shock to energies of 1 to 10 keV. The direction of the electron bulk flow direction changes abruptly between 1920 and 1922 UT, and the flow speed begins a sharp decline at the same time. It is suggested that the spacecraft entered the bow shock wave between 1920 and 1922 UT. Electron density variations at Halley are very much smaller than those at Giacobini-Zinner

  18. Confinement properties of tokamak plasmas with extended regions of low magnetic shear

    Science.gov (United States)

    Graves, J. P.; Cooper, W. A.; Kleiner, A.; Raghunathan, M.; Neto, E.; Nicolas, T.; Lanthaler, S.; Patten, H.; Pfefferle, D.; Brunetti, D.; Lutjens, H.

    2017-10-01

    Extended regions of low magnetic shear can be advantageous to tokamak plasmas. But the core and edge can be susceptible to non-resonant ideal fluctuations due to the weakened restoring force associated with magnetic field line bending. This contribution shows how saturated non-linear phenomenology, such as 1 / 1 Long Lived Modes, and Edge Harmonic Oscillations associated with QH-modes, can be modelled accurately using the non-linear stability code XTOR, the free boundary 3D equilibrium code VMEC, and non-linear analytic theory. That the equilibrium approach is valid is particularly valuable because it enables advanced particle confinement studies to be undertaken in the ordinarily difficult environment of strongly 3D magnetic fields. The VENUS-LEVIS code exploits the Fourier description of the VMEC equilibrium fields, such that full Lorenzian and guiding centre approximated differential operators in curvilinear angular coordinates can be evaluated analytically. Consequently, the confinement properties of minority ions such as energetic particles and high Z impurities can be calculated accurately over slowing down timescales in experimentally relevant 3D plasmas.

  19. The Plasma Parameters and Geometry of Cool and Warm Active Region Loops

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Haixia; Li, Bo; Huang, Zhenghua; Xia, Lidong; Fu, Hui; Mou, Chaozhou [Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai, 264209 Shandong (China); Madjarska, Maria S.; Wiegelmann, Thomas [Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, D-37077, Göttingen (Germany)

    2017-06-10

    How the solar corona is heated to high temperatures remains an unsolved mystery in solar physics. In the present study we analyze observations of 50 whole active region loops taken with the Extreme-ultraviolet Imaging Spectrometer on board the Hinode satellite. Eleven loops were classified as cool loops (<1 MK) and 39 as warm loops (1–2 MK). We study their plasma parameters, such as densities, temperatures, filling factors, nonthermal velocities, and Doppler velocities. We combine spectroscopic analysis with linear force-free magnetic field extrapolation to derive the 3D structure and positioning of the loops, their lengths and heights, and the magnetic field strength along the loops. We use density-sensitive line pairs from Fe xii, Fe xiii, Si x, and Mg vii ions to obtain electron densities by taking special care of intensity background subtraction. The emission measure loci method is used to obtain the loop temperatures. We find that the loops are nearly isothermal along the line of sight. Their filling factors are between 8% and 89%. We also compare the observed parameters with the theoretical Rosner–Tucker–Vaiana (RTV) scaling law. We find that most of the loops are in an overpressure state relative to the RTV predictions. In a follow-up study, we will report a heating model of a parallel-cascade-based mechanism and will compare the model parameters with the loop plasma and structural parameters derived here.

  20. Electron backstream to the source plasma region in an ion source

    International Nuclear Information System (INIS)

    Ohara, Y.; Akiba, M.; Arakawa, Y.; Okumura, Y.; Sakuraba, J.

    1980-01-01

    The flux of backstream electrons to the source plasma region increases significantly with the acceleration voltage of an ion beam, so that the back plate in the arc chamber should be broken for quasi-dc operation. The flux of backstream electrons is estimated at the acceleration voltage of 50--100 kV for a proton beam with the aid of ion beam simulation code. The power flux of backstream electrons is up to about 7% of the total beam output at the acceleration voltage of 75 kV. It is pointed out that the conventional ion sources such as the duoPIGatron or the bucket source which use a magnetic field for source plasma production are not suitable for quasi-dc and high-energy ion sources, because the surface heat flux of the back plate is increased by the focusing of backstream electrons and the removal of it is quite difficult. A new ion source which has an electron beam dump in the arc chamber is proposed

  1. The Impacts of Different PBL Schemes on the Simulation of PM2.5 during Severe Haze Episodes in the Jing-Jin-Ji Region and Its Surroundings in China

    Directory of Open Access Journals (Sweden)

    Tian Li

    2016-01-01

    Full Text Available In this study, three schemes [Yonsei University (YSU, Mellor-Yamada-Janjic (MYJ, and Bougeault-Lacarrère (Boulac] were employed in the Weather Research and Forecasting/Chemistry (WRF-Chem model to simulate the severe haze that occurred in February 2014 in the Jing-Jin-Ji region and its surroundings. The PM2.5 concentration simulated using the three schemes, together with the meteorological factors closely related to PM2.5 (wind speed, local vertical diffusivity, and PBL height, was evaluated through comparison with observations. The results indicated that the eastern plain cities produced better simulation results than the western cities, and the cities under the eastern root of Taihang Mountain produced the worst results in simulating high PM2.5 concentration in haze. All three schemes simulated very similar variation trends of the surface PM2.5 concentration compared with observations. The diurnal variations of simulated surface PM2.5 were not as reasonable as their reflection of daily averaged variation. The simulated concentrations of surface PM2.5 using the YSU, MYJ, and Boulac schemes all showed large negative errors during daytime in polluted days due to their inefficient descriptions of local atmospheric stability or diffusion processes in haze. The lower ability of PBL schemes in distinguishing the diffusion between haze and clean days in the complex topography areas in China is an important problem for PM2.5 forecasting, which is worthy of being studied in detail.

  2. Determination of arsenic in some water bodies, untreated ore and tailing samples at Konongo in the Ashanti region of Ghana and its surrounding towns and villages by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Boadu, M.; Osae, E.K.; Serfor-Armah, Y.; Nyarko, B.J.B.; Golow, A.A.

    2001-01-01

    Instrumental neutron activation analysis (INAA) has been employed for the determination of arsenic in samples of water bodies at Konongo an old mining town in the Ashanti region of Ghana and its surrounding towns and villages. In some of the water samples, significant levels of arsenic were recorded but others gave no indication of the metal. The precision and accuracy of the method was evaluated using real ore samples and standard reference materials. The accuracy of the method was found to be within ±6%. The average arsenic levels found in the water samples ranged between 0.04 and 12.2 mg/l. Untreated ore and tailing samples were also analysed for arsenic. The surface ore gave an arsenic concentration of 4,628 ± 97 ppm while that of the bottom ore was 2,978 ± 69 ppm. For the tailing samples, the range of arsenic level was 1,776 to 1,787 ppm. It was observed that the upper sink (i.e., the surface portion of the ore) showed higher levels of arsenic than the lower one (i.e., bottom portion of the ore). (author)

  3. Lateral mobility of plasma membrane lipids in Xenopus eggs: Regional differences related to animal/vegetal polarity

    OpenAIRE

    Laat, S.W. de; Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van; Tetteroo, P.A.T.; Tertoolen, L.G.J.

    1984-01-01

    Regional differences in the lateral mobility properties of plasma membrane lipids were studied in unfertilized and fertilized Xenopus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein- -1abelled fatty acids HEDAF (5-(N-hexadecanoyl)- aminofluorescein) and TEDAF (5-(N-tetradecanoyl)-aminofluorescein) appear to distribute itself in the plasma membrane. Under all experimental conditions used these molecules s...

  4. Plasma interface of the EC waves to the LHD peripheral region

    Science.gov (United States)

    Kubo, S.; Igami, H.; Tsujimura, T. I.; Shimozuma, T.; Takahashi, H.; Yoshimura, Y.; Nishiura, M.; Makino, R.; Mutoh, T.

    2015-12-01

    In order to realize an efficient ECRH and also to reduce stray radiation due to non-absorbed power during ECRH, it is necessary to excite a wave that is absorbed well near the electron cyclotron resonance. In the normal fusion magnetic field confinement machine and in the electron cyclotron frequency range, WKB approximation is valid almost all the way from antenna to the absorption region due to the large scale-length of the plasma density λn and the magnetic shear τs as compared with the local wavelength λ0. In these situation, it is well known that the O/X mode propagates as O/X mode if τs ≫ λ0. Even in these situation, if τs and λn are comparable and |1/λO-1/λX|τs ≪ 1, there still remains the question from where "X" - or "O" - mode become "X" - or "O" mode at the peripheral region. In order to simulate this situation, one dimensional full wave calculation code which solve electromagnetic wave equation under arbitrary magnetic field configuration and arbitrary density profile for a given polarization state are developed and incorporated in the upgraded ray tracing code LHDGauss. It is tried to find the density and shear scale lengths region where the mode mixing effect is not negligible.

  5. Plasma interface of the EC waves to the LHD peripheral region

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, S., E-mail: kubo@lhd.nifs.ac.jp; Igami, H.; Tsujimura, T. I.; Shimozuma, T.; Takahashi, H.; Yoshimura, Y.; Makino, R.; Mutoh, T. [National Institute for Fusion Science, Toki, 509-5292 (Japan); Nishiura, M. [Grad. School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561 (Japan)

    2015-12-10

    In order to realize an efficient ECRH and also to reduce stray radiation due to non-absorbed power during ECRH, it is necessary to excite a wave that is absorbed well near the electron cyclotron resonance. In the normal fusion magnetic field confinement machine and in the electron cyclotron frequency range, WKB approximation is valid almost all the way from antenna to the absorption region due to the large scale-length of the plasma density λ{sub n} and the magnetic shear τ{sub s} as compared with the local wavelength λ{sub 0}. In these situation, it is well known that the O/X mode propagates as O/X mode if τ{sub s} ≫ λ{sub 0}. Even in these situation, if τ{sub s} and λ{sub n} are comparable and |1/λ{sub O}−1/λ{sub X}|τ{sub s} ≪ 1, there still remains the question from where ”X” - or ”O” - mode become ”X” - or ”O” mode at the peripheral region. In order to simulate this situation, one dimensional full wave calculation code which solve electromagnetic wave equation under arbitrary magnetic field configuration and arbitrary density profile for a given polarization state are developed and incorporated in the upgraded ray tracing code LHDGauss. It is tried to find the density and shear scale lengths region where the mode mixing effect is not negligible.

  6. VHF and HF radar measurements of E and R region plasma drifts at the magnetic equator

    International Nuclear Information System (INIS)

    Viswanathan, K.S.; Namboothiri, S.P.; Rao, P.B.

    1992-01-01

    Simultaneous observations of E region horizontal irregularity drifts by VHF backscatter radar and of F region vertical plasma drift by HF Doppler radar conducted during daytime on a few magnetically quiet days at Trivandrum (dip 0.2 degree N) are presented. A comparative study of the two measurements indicates broadly (1) a resemblance in the daytime changes of the E-W component between the electric field and (2) evidence of quasi-periodic electric field variations with periods ranging mostly from 1 to 2 hours. The electric fields derived from HF Doppler radar observations are somewhat lower than those deduced by HVHF radar observations. The correlation coefficient for the variations of the electric fields measured by the two experimental techniques is found to be in the range of about 0.5 to 0.9. The observed difference in the E and F region electric fields at the magnetic equator is discussed in terms of the measurement uncertainties and the limitations involved in deriving E-W electric fields. The observations are suggestive of a latitudinal variation in the E-W component of the electric field in the equatorial ionosphere

  7. Image-converter diagnostics of laser and laser plasma in pico-femtosecond region

    International Nuclear Information System (INIS)

    Schelev, M.Ya.

    1979-01-01

    In the present communication we would like to outline some new trends in development of pico-femtosecond image-converter diagnostics for laser and laser plasma research on the basis of the recent works done in P.N.Lebedev Physical Institute. The discussion of the following subjects will be included: new generation of picosecond image-converter tubes (ICT), pulsed control circuitry, late prototype of picosecond image-converter cameras (ICC), test installation consisting of Nd: glass and YAG lasers for production the ultra-short pulses and sinusoidally modulated radiation, methods and techniques for image tube and camera dynamic measurements in IR, visible and X-ray spectral regions. Also discussed are the image processing technique for pictures taken with picosecond ICC in order to correct the geometrical distortions, enhance pictures quality and evaluate parameters of the input signals through their recorded images. (author)

  8. Some analyses on the plasma motion in the space active region of the axial symmetry

    International Nuclear Information System (INIS)

    Li Zhongyuan; Hu Wenrui.

    1986-04-01

    In general, the potential magnetic field may gradually be twisted into the force-free magnetic field with the current produced by plasma rotation. In this paper, it is pointed out that if the magnetic field has no singularity on the symmetric axis, then the potential magnetic field cannot be twisted into the force-free magnetic field. Namely, it is not a perfect approach that the energy storage is only caused by the pure azimuthal motion in the active region. Besides the pure spiral motion, the unsteady coupling process between the magnetic field and both the toroidal and the poloidal velocity components should be analyzed. Finally, in the present note, some features of the kinematical force-free magnetic field of the axial symmetry are presented by the authors. (author)

  9. Ionization processes in the Fe 27 region of hot iron plasma in the field of hard gamma radiation

    International Nuclear Information System (INIS)

    Illarionov, A.F.

    1989-01-01

    A highly ionized hot plasma of an iron 26 56 Fe-type heavy element in the field of hard ionizing gamma-ray radiation is considered. The processes of ionization and recombination are discussed for a plasma consisting of the fully ionized Fe 27 and the hydrogen-like Fe 26 ions of iron in the case of large optical depth of the plasma with respect to the photoionization by gamma-ray quanta. The self-ionization process of a hot plasma with the temperature kT ≅ I (I being the ionization potential), due to the production of the own ionizing gamma-ray quanta, by the free-free (ff) and recombination (fb) radiation mechanisms, is investigated. It is noted that in the stationary situation the process of self-ionization of a hot plasma imposes the restriction upon the plasma temperature, kT<1.5 I. It is shown that the ionization of heavy-ion plasma by the impact of thermal electrons is dominating over the processes of ff- and fb-selfionization of plasma only by the large concentration of hydrogen-like iron at the periphery of the region of fully ionized iron Fe 27

  10. Relation of zonal plasma drift and wind in the equatorial F region as derived from CHAMP observations

    Directory of Open Access Journals (Sweden)

    J. Park

    2013-06-01

    Full Text Available In this paper we estimate zonal plasma drift in the equatorial ionospheric F region without counting on ion drift meters. From June 2001 to June 2004 zonal plasma drift velocity is estimated from electron, neutral, and magnetic field observations of Challenging Mini-satellite Payload (CHAMP in the 09:00–20:00 LT sector. The estimated velocities are validated against ion drift measurements by the Republic of China Satellite-1/Ionospheric Plasma and Electrodynamics Instrument (ROCSAT-1/IPEI during the same period. The correlation between the CHAMP (altitude ~ 400 km estimates and ROCSAT-1 (altitude ~ 600 km observations is reasonably high (R ≈ 0.8. The slope of the linear regression is close to unity. However, the maximum westward drift and the westward-to-eastward reversal occur earlier for CHAMP estimates than for ROCSAT-1 measurements. In the equatorial F region both zonal wind and plasma drift have the same direction. Both generate vertical currents but with opposite signs. The wind effect (F region wind dynamo is generally larger in magnitude than the plasma drift effect (Pedersen current generated by vertical E field, thus determining the direction of the F region vertical current.

  11. Production of accelerated electrons near an electron source in the plasma resonance region

    International Nuclear Information System (INIS)

    Fedorov, V.A.

    1989-01-01

    Conditions of generation of plasma electrons accelerated and their characteristics in the vicinity of an electron source are determined. The electron source isolated electrically with infinitely conducting surface, being in unrestricted collisionless plasma ω 0 >>ν, where ω 0 - plasma frequency of nonperturbated plasma, ν - frequency of plasma electron collisions with other plasma particles, is considered. Spherically symmetric injection of electrons, which rates are simulated by ω frequency, occurs from the source surface. When describing phenomena in the vicinity of the electron source, one proceeds from the quasihydrodynamic equation set

  12. Comparison of excitation mechanisms in the analytical regions of a high-power two-jet plasma

    International Nuclear Information System (INIS)

    Zaksas, Natalia P.

    2015-01-01

    Excitation mechanisms in the analytical regions of a high-power two-jet plasma were investigated. A new plasmatron recently developed was applied in this work. The Boltzmann population of excited levels of Fe atoms and ions was observed in both analytical regions, before and after the jet confluence, as well as in the jet confluence, which proves excitation of atoms and ions by electron impact. The disturbance of local thermodynamic equilibrium in all regions of the plasma flow was deduced on the basis of considerable difference in Fe atomic and ionic excitation temperatures. Such a difference is most likely to be caused by contribution of metastable argon to atom ionization. The region before the jet confluence has the greatest difference in Fe atomic and ionic excitation temperatures and is more non-equilibrium than the region after the confluence due to comparatively low electron and high metastable argon concentrations. Low electron concentration in this region provides lower background emission than in the region after the jet confluence, which leads to better detection limits for the majority of elements. - Highlights: • Excitation mechanisms were investigated in the analytical regions of a high-power TJP. • Boltzmann population of excited levels of Fe atoms and ions takes place in all regions of the plasma flow. • The considerable difference in Fe atomic and ionic excitation temperatures occurs. • Penning ionization by metastable argon results in disturbance of LTE in the plasma. • The region before the jet confluence is more non-equilibrium than after that

  13. In planta processing and glycosylation of a nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-like effector and its interaction with a host CLAVATA2-like receptor to promote parasitism.

    Science.gov (United States)

    Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S; Mitchum, Melissa G; Wang, Xiaohong

    2015-01-01

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. © 2015 American Society of Plant Biologists. All Rights Reserved.

  14. In Planta Processing and Glycosylation of a Nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-Like Effector and Its Interaction with a Host CLAVATA2-Like Receptor to Promote Parasitism1[OPEN

    Science.gov (United States)

    Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S.; Mitchum, Melissa G.

    2015-01-01

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. PMID:25416475

  15. Plasma needle treatment of bacteria known to cause infections of the soft tissue of the oral region and bones

    Science.gov (United States)

    Maletic, Dejan; Lazovic, Sasa; Puac, Nevena; Malovic, Gordana; Petrovic, Zoran Lj.; Miletic, Maja P.; Pavlica, Dusan B.; Jovanovic, Milena Z.; Milenkovic, Pavle

    2009-10-01

    Plasma needle can be used for non-contact disinfection of dental cavities and wounds, minimum-destructive precise treatment, as well as the removal of damaged tissue. The effect of bacterial deactivation is probably caused by reactive oxygen species while nitric oxide provided by plasma plays major role in many processes in the organism. Mass spectrometry was done to provide better insight into plasma-cell interactions. Our measurements were performed on a plasma needle that we originally used for the treatment of plant cells.Our research was done on species that are known to cause primary and secondary infections of the soft tissue of the oral region, as well as bones. The bacteria cultures used are bacterial reference culture species Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922. We investigated the effect of the plasma needle discharge on different concentration of bacteria using several exposure times and power transmitted to the plasma. It was found that excellent removal of this and other bacteria may be achieved by the plasma needle treatment.

  16. RF plasma based selective modification of hydrophilic regions on super hydrophobic surface

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jaehyun; Hwang, Sangyeon; Cho, Dae-Hyun [Department of Mechanical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Hong, Jungwoo [Department of Mechanical Engineering, Graduate of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141 (Korea, Republic of); Shin, Jennifer H., E-mail: j_shin@kaist.ac.kr [Department of Mechanical Engineering, Graduate of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141 (Korea, Republic of); Byun, Doyoung, E-mail: dybyun@skku.edu [Department of Mechanical Engineering, Sungkyunkwan University, Suwon 16419 (Korea, Republic of)

    2017-02-01

    Highlights: • Simple and amenable reforming method for a substrate with disparate patterns of hydrophilic dots on super-hydrophobic surfaces is proposed. • Wettability characteristics and modification mechanism for the surfaces are conducted and revealed through SEM, AFM, WSI, and SIMS. • Several representative materials for various applications are successfully deposited. - Abstract: Selective modification and regional alterations of the surface property have gained a great deal of attention to many engineers. In this paper, we present a simple, a cost-effective, and amendable reforming method for disparate patterns of hydrophilic regions on super-hydrophobic surfaces. Uniform super-hydrophobic layer (Contact angle; CA > 150°, root mean square (RMS) roughness ∼0.28 nm) can be formed using the atmospheric radio frequency (RF) plasma on top of the selective hydrophilic (CA ∼ 70°, RMS roughness ∼0.34 nm) patterns imprinted by electrohydrodynamic (EHD) jet printing technology with polar alcohols (butyl carbitol or ethanol). The wettability of the modified surface was investigated qualitatively utilizing scanning electron microscopy (SEM), atomic force microscopy (AFM), and wavelength scanning interferometer (WSI). Secondary ion mass spectroscopy (SIMS) analysis showed that the alcohol addiction reaction changed the types of radicals on the super-hydrophobic surface. The wettability was found to depend sensitively on chemical radicals on the surface, not on surface morphology (particle size and surface roughness). Furthermore, three different kinds of representative hydrophilic samples (polystyrene nano-particle aqueous solution, Salmonella bacteria medium, and poly(3,4-ethylenediocythiophene) ink) were tested for uniform deposition onto the desired hydrophilic regions. This simple strategy would have broad applications in various research fields that require selective deposition of target materials.

  17. RF plasma based selective modification of hydrophilic regions on super hydrophobic surface

    International Nuclear Information System (INIS)

    Lee, Jaehyun; Hwang, Sangyeon; Cho, Dae-Hyun; Hong, Jungwoo; Shin, Jennifer H.; Byun, Doyoung

    2017-01-01

    Highlights: • Simple and amenable reforming method for a substrate with disparate patterns of hydrophilic dots on super-hydrophobic surfaces is proposed. • Wettability characteristics and modification mechanism for the surfaces are conducted and revealed through SEM, AFM, WSI, and SIMS. • Several representative materials for various applications are successfully deposited. - Abstract: Selective modification and regional alterations of the surface property have gained a great deal of attention to many engineers. In this paper, we present a simple, a cost-effective, and amendable reforming method for disparate patterns of hydrophilic regions on super-hydrophobic surfaces. Uniform super-hydrophobic layer (Contact angle; CA > 150°, root mean square (RMS) roughness ∼0.28 nm) can be formed using the atmospheric radio frequency (RF) plasma on top of the selective hydrophilic (CA ∼ 70°, RMS roughness ∼0.34 nm) patterns imprinted by electrohydrodynamic (EHD) jet printing technology with polar alcohols (butyl carbitol or ethanol). The wettability of the modified surface was investigated qualitatively utilizing scanning electron microscopy (SEM), atomic force microscopy (AFM), and wavelength scanning interferometer (WSI). Secondary ion mass spectroscopy (SIMS) analysis showed that the alcohol addiction reaction changed the types of radicals on the super-hydrophobic surface. The wettability was found to depend sensitively on chemical radicals on the surface, not on surface morphology (particle size and surface roughness). Furthermore, three different kinds of representative hydrophilic samples (polystyrene nano-particle aqueous solution, Salmonella bacteria medium, and poly(3,4-ethylenediocythiophene) ink) were tested for uniform deposition onto the desired hydrophilic regions. This simple strategy would have broad applications in various research fields that require selective deposition of target materials.

  18. Spectra of germanium and selenium in the 50-350 A region from the PLT tokamak plasma

    International Nuclear Information System (INIS)

    Stratton, B.C.; Hodge, W.L.; Moos, H.W.; Schwob, J.L.; Suckewer, S.; Finkenthal, M.; Cohen, S.

    1983-03-01

    Spectra of germanium and selenium injected into the PLT tokamak plasma were observed in the 50 to 350 A region for GeXIV-XXV (KI to OI-like) and SeXVI-XXIV (KI to NaI-like). A number of 3p/sup k/-3p/sup k-1/3d transitions predicted by isoelectronic sequence extrapolation have been identified. Also, previously identified lines from ions in the AlI to OI-like and KI-like isoelectronic sequences have been observed in the tokamak plasma

  19. Identification of Y-shaped and O-shaped diffusion regions during magnetic reconnection in a laboratory plasma

    International Nuclear Information System (INIS)

    Yamada, Masaaki; Ji, H.; Hsu, S.; Carter, T.; Kulsrud, R.; Ono, Yasushi; Perkins, F.

    1997-01-01

    Two strikingly different shapes of diffusion regions are identified during magnetic reconnection in a magnetohydrodynamic laboratory plasma. The shapes depend on the third vector component of the reconnecting magnetic fields. Without the third component (anti-parallel or null-helicity reconnection), a thin double-Y shaped diffusion region is identified. In this case, the neutral sheet current profile is accurately measured to be as narrow as the order of the ion gyro-radius. In the presence of an appreciable third component (co-helicity reconnection), an O-shaped diffusion region appears and grows into a spheromak configuration

  20. INFERENCE OF HEATING PROPERTIES FROM “HOT” NON-FLARING PLASMAS IN ACTIVE REGION CORES. I. SINGLE NANOFLARES

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, W. T.; Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77251-1892 (United States); Cargill, P. J., E-mail: will.t.barnes@rice.edu [Space and Atmospheric Physics, The Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)

    2016-09-20

    The properties that are expected of “hot” non-flaring plasmas due to nanoflare heating in active regions are investigated using hydrodynamic modeling tools, including a two-fluid development of the Enthalpy Based Thermal Evolution of Loops code. Here we study a single nanoflare and show that while simple models predict an emission measure distribution extending well above 10 MK, which is consistent with cooling by thermal conduction, many other effects are likely to limit the existence and detectability of such plasmas. These include: differential heating between electrons and ions, ionization non-equilibrium, and for short nanoflares, the time taken for the coronal density to increase. The most useful temperature range to look for this plasma, often called the “smoking gun” of nanoflare heating, lies between 10{sup 6.6} and 10{sup 7} K. Signatures of the actual heating may be detectable in some instances.

  1. Measurement of potentials in the wake region of an unmagnetized plasma by using a DC-heated emissive probe

    International Nuclear Information System (INIS)

    Jung, Yong Ho; Chung, Kyu Sun

    1995-01-01

    An emissive probe was designed and manufactured to measure the floating and the space potentials of a plasma in the wake region. The 'floating potential method', among various schemes, was used for the measurement and analysis. To generate the wake, a plane artificial satellite with a circular shape was introduced into a simply discharged argon plasma without a magnetic field. Potentials along the radial direction in and out of the wake region of the artificial satellite were measured, and the plasma parameters were compared in both regions. In the wake region, the floating potential was higher than that out of the wake; the space potential was approximately equal to that out of the wake; when a positive voltage was applied to the artificial satellite, the floating and the space potentials were lower than those out of the wake; and when a negative voltage was applied to the artificial satellite, the floating potential was higher and the space potential was lower than the corresponding potentials out of the wake. (author)

  2. Circumstances surrounding aneurysmal subarachnoid hemorrhage

    NARCIS (Netherlands)

    Schievink, W. I.; Karemaker, J. M.; Hageman, L. M.; van der Werf, D. J.

    1989-01-01

    The circumstances surrounding aneurysmal subarachnoid hemorrhage were investigated in a group of 500 consecutive patients admitted to a neurosurgical center. Subarachnoid hemorrhage occurred during stressful events in 42.8% of the patients, during nonstrenuous activities in 34.4%, and during rest or

  3. Development and application of a multiscale model for the magnetic fusion edge plasma region

    International Nuclear Information System (INIS)

    Hasenbeck, Felix Martin Michael

    2016-01-01

    remains diffusive. An analytic expression for the diffusion coefficient D is found, being consistent with results from percolation theory. The multiscale model and the coupling procedure are benchmarked with a one-dimensional test problem which consists of coupling the local version of the drift fluid code ATTEMPT to a 1D macroscale code to determine the time-dependent evolution of the flux surface averaged density in radial direction in the tokamak edge region. The reference simulation is given by a simulation of the non-local version of ATTEMPT, accounting for both the mesoscale and the macroscale evolution. Results of the coupled code simulations show that the macroscale evolution of the density and the radial particle flux can be reproduced with typical uncertainties of 6 and 22%, respectively. Time savings with respect to the non-local simulations are of a factor of ten for a typical macroscale evolution time of 10 milliseconds while a speedup factor of the order of 50 is achievable for an edge region with a radial extent of ∝ 30 cm and typical radial profile lengths of ∝5 cm. The multiscale model for two-dimensional, stationary problems is realized by coupling of the B2 code and the local version of the ATTEMPT code. The results of the corresponding coupled code simulations for experiments at the tokamak TEX TOR provide plasma profiles in agreement with experimental measurements with uncertainties regarding the electron density and electron temperature measured at the outer midplane around 10 to 25%. Poloidally and radially dependent profiles of the radial particle diffusion coefficients D, self-consistently determined by B2-ATTEMPT, have typical values of 0.3 to 0.9 m"2s"-"1 and are within a 10 to 30% range of effective diffusion coefficients employed in B2-EIRENE simulations to fit simulation results to measured density profiles. The poloidal dependence of D as given by the B2-ATTEMPT simulations accounts for the experimentally confirmed ballooning character

  4. Development and application of a multiscale model for the magnetic fusion edge plasma region

    Energy Technology Data Exchange (ETDEWEB)

    Hasenbeck, Felix Martin Michael

    2016-07-01

    remains diffusive. An analytic expression for the diffusion coefficient D is found, being consistent with results from percolation theory. The multiscale model and the coupling procedure are benchmarked with a one-dimensional test problem which consists of coupling the local version of the drift fluid code ATTEMPT to a 1D macroscale code to determine the time-dependent evolution of the flux surface averaged density in radial direction in the tokamak edge region. The reference simulation is given by a simulation of the non-local version of ATTEMPT, accounting for both the mesoscale and the macroscale evolution. Results of the coupled code simulations show that the macroscale evolution of the density and the radial particle flux can be reproduced with typical uncertainties of 6 and 22%, respectively. Time savings with respect to the non-local simulations are of a factor of ten for a typical macroscale evolution time of 10 milliseconds while a speedup factor of the order of 50 is achievable for an edge region with a radial extent of ∝ 30 cm and typical radial profile lengths of ∝5 cm. The multiscale model for two-dimensional, stationary problems is realized by coupling of the B2 code and the local version of the ATTEMPT code. The results of the corresponding coupled code simulations for experiments at the tokamak TEX TOR provide plasma profiles in agreement with experimental measurements with uncertainties regarding the electron density and electron temperature measured at the outer midplane around 10 to 25%. Poloidally and radially dependent profiles of the radial particle diffusion coefficients D, self-consistently determined by B2-ATTEMPT, have typical values of 0.3 to 0.9 m{sup 2}s{sup -1} and are within a 10 to 30% range of effective diffusion coefficients employed in B2-EIRENE simulations to fit simulation results to measured density profiles. The poloidal dependence of D as given by the B2-ATTEMPT simulations accounts for the experimentally confirmed ballooning

  5. Gettering high energy plasma in the end loss region of the Mirror Fusion Test Facility

    International Nuclear Information System (INIS)

    Goldner, A.I.; Margolies, D.S.

    1979-01-01

    The ions escaping from the end loss fan of the Mirror Fusion Test Facility (MFTF) neutralize when they hit the surface of the end dome. If the neutrals then bounce back into the oncoming plasma, they are likely to reionize, drawing power from the center of the plasma and reducing the overall electron temperature. In this paper we describe two methods for reducing the reionization rate and a computer code for estimating their effectiveness

  6. Remote sensing of auroral E region plasma structures by radio, radar, and UV techniques at solar minimum

    International Nuclear Information System (INIS)

    Basu, S.; Valladares, C.E.; Basu, S.; Eastes, R.; Huffman, R.E.; Daniell, R.E.; Chaturvedi, P.K.; Livingston, R.C.

    1993-01-01

    The unique capability of the Polar BEAR satellite to simultaneously image auroral luminosities at multiple ultraviolet (UV) wavelengths and to remote sense large-scale (hundreds to tens of kilometers) and small-scale (kilometers to hundreds of meters) plasma density structures with its multifrequency beacon package is utilized to probe the auroral E region in the vicinity of the incoherent scatter radar (ISR) facility near Sondrestrom. In particular, we present coordinated observations on two nights obtained during the sunspot minimum (sunspot number < 10) January-February 1987 period when good spatial and temporal conjunction was obtained between Polar BEAR overflights and Sondrestrom ISR measurements. With careful coordinated observations we were able to confirm that the energetic particle precipitation responsible for the UV emissions causes the electron density increases in the E region. The integrations up to the topside of these ISR electron density profiles were consistent with the total electron content (TEC) measured by the Polar BEAR satellite. An electron transport model was utilized to determine quantitatively the electron density profiles which could be produced by the particle precipitation, which also produced multiple UV emissions measured by the imager; these profiles were found to be in good agreement with the observed ISR profiles in the E region. This outer scale size is also consistent with the measured phase to amplitude scintillation ratio. An estimate of the linear growth rate of the gradient-drift instability in the E region shows that these plasma density irregularities could have been generated by this process. The mutual consistency of these different sets of measurements provides confidence in the ability of the different techniques to remote sense large- and small-scale plasma density structures in the E region at least during sunspot minimum when the convection-dominated high-latitude F region is fairly weak. 56 refs., 16 figs

  7. Experimental study of the Hall effect and electron diffusion region during magnetic reconnection in a laboratory plasma

    International Nuclear Information System (INIS)

    Ren Yang; Yamada, Masaaki; Ji Hantao; Dorfman, Seth; Gerhardt, Stefan P.; Kulsrud, Russel

    2008-01-01

    The Hall effect during magnetic reconnection without an external guide field has been extensively studied in the laboratory plasma of the Magnetic Reconnection Experiment [M. Yamada et al., Phys. Plasmas 4, 1936 (1997)] by measuring its key signature, an out-of-plane quadrupole magnetic field, with magnetic probe arrays whose spatial resolution is on the order of the electron skin depth. The in-plane electron flow is deduced from out-of-plane magnetic field measurements. The measured in-plane electron flow and numerical results are in good agreement. The electron diffusion region is identified by measuring the electron outflow channel. The width of the electron diffusion region scales with the electron skin depth (∼5.5-7.5c/ω pe ) and the peak electron outflow velocity scales with the electron Alfven velocity (∼0.12-0.16V eA ), independent of ion mass. The measured width of the electron diffusion region is much wider and the observed electron outflow is much slower than those obtained in 2D numerical simulations. It is found that the classical and anomalous dissipation present in the experiment can broaden the electron diffusion region and slow the electron outflow. As a consequence, the electron outflow flux remains consistent with numerical simulations. The ions, as measured by a Mach probe, have a much wider outflow channel than the electrons, and their outflow is much slower than the electron outflow everywhere in the electron diffusion region

  8. The ‘churning mode’ of plasma convection in the tokamak divertor region

    International Nuclear Information System (INIS)

    Ryutov, D D; Cohen, R H; Farmer, W A; Rognlien, T D; Umansky, M V

    2014-01-01

    The churning mode can arise in a toroidally-symmetric plasma where it causes convection in the vicinity of the poloidal magnetic field null. The mode is driven by the toroidal curvature of magnetic field lines coupled with a pressure gradient. The toroidal equilibrium conditions cannot be satisfied easily in the virtual absence of the poloidal field (PF)—hence the onset of this mode, which ‘churns’ the plasma around the PF null without perturbing the strong toroidal field. We find the conditions under which this mode can be excited in magnetic configurations with first-, second-, and third-order PF nulls (i.e., in the geometry of standard, snowflake and cloverleaf divertors). The size of the affected zone in second- and third-order-null divertors is much larger than in a standard first-order-null divertor. The proposed phenomenological theory allows one to evaluate observable characteristics of the mode, in particular the frequency and amplitude of the PF perturbations. The mode spreads the tokamak heat exhaust between multiple divertor legs and may lead to a broadening of the plasma width in each leg. The mode causes much more intense plasma convection in the poloidal plane than the classical plasma drifts. (invited comment)

  9. Opportunity's Surroundings on Sol 1818 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,818th Martian day, or sol, of Opportunity's surface mission (March 5, 2009). South is at the center; north at both ends. This view is presented as a vertical projection with geometric seam correction. North is at the top. The rover had driven 80.3 meters (263 feet) southward earlier on that sol. Tracks from the drive recede northward in this view. The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock.

  10. Opportunity's Surroundings on Sol 1818 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,818th Martian day, or sol, of Opportunity's surface mission (March 5, 2009). South is at the center; north at both ends. This view is presented as a polar projection with geometric seam correction. North is at the top. The rover had driven 80.3 meters (263 feet) southward earlier on that sol. Tracks from the drive recede northward in this view. The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock.

  11. Plasma Vitamin E and Blood Selenium Concentrations in Norwegian Dairy Cows: Regional Differences and Relations to Feeding and Health

    Directory of Open Access Journals (Sweden)

    Østerås O

    2005-12-01

    Full Text Available Plasma α-tocopherol (vit E and blood selenium (Se concentrations in February were determined in samples from 314 dairy cows in Norway, selected to provide a representative subset of the Norwegian dairy cow population. Each sample was followed by a questionnaire with information about feeding of the cow at the time of sampling. The results were correlated to herd data and to calving and health data for each cow from the Norwegian Dairy Herd Recording System and the Norwegian Cattle Health Recording System. The mean concentrations were 6.9 μg vit E per ml plasma and 0.16 μg Se per g blood. Both levels were highest in mid lactation. Plasma vit E varied with the amount of silage fed to the cow, while blood Se varied with the amount of concentrates and mineral supplements, and with geographical region. No differences in vit E or Se levels were found between cows with recorded treatments for mastitis, parturient paresis or reproductive disorders in the lactation during or immediately prior to sampling, and those without such treatments. For ketosis, a small difference in blood Se was found between the groups with or without recorded treatments. It is concluded that winter-fed lactating cows in Norway had an adequate plasma level of vit E and a marginal-to-adequate level of Se.

  12. Plasma Vitamin E and Blood Selenium Concentrations in Norwegian Dairy Cows: Regional Differences and Relations to Feeding and Health

    Directory of Open Access Journals (Sweden)

    Sivertsen T

    2006-12-01

    Full Text Available Plasma α-tocopherol (vit E and blood selenium (Se concentrations in February were determined in samples from 314 dairy cows in Norway, selected to provide a representative subset of the Norwegian dairy cow population. Each sample was followed by a questionnaire with information about feeding of the cow at the time of sampling. The results were correlated to herd data and to calving and health data for each cow from the Norwegian Dairy Herd Recording System and the Norwegian Cattle Health Recording System. The mean concentrations were 6.9 μg vit E per ml plasma and 0.16 μg Se per g blood. Both levels were highest in mid lactation. Plasma vit E varied with the amount of silage fed to the cow, while blood Se varied with the amount of concentrates and mineral supplements, and with geographical region. No differences in vit E or Se levels were found between cows with recorded treatments for mastitis, parturient paresis or reproductive disorders in the lactation during or immediately prior to sampling, and those without such treatments. For ketosis, a small difference in blood Se was found between the groups with or without recorded treatments. It is concluded that winter-fed lactating cows in Norway had an adequate plasma level of vit E and a marginal-to-adequate level of Se.

  13. Severe blood-brain barrier disruption and surrounding tissue injury.

    Science.gov (United States)

    Chen, Bo; Friedman, Beth; Cheng, Qun; Tsai, Phil; Schim, Erica; Kleinfeld, David; Lyden, Patrick D

    2009-12-01

    Blood-brain barrier opening during ischemia follows a biphasic time course, may be partially reversible, and allows plasma constituents to enter brain and possibly damage cells. In contrast, severe vascular disruption after ischemia is unlikely to be reversible and allows even further extravasation of potentially harmful plasma constituents. We sought to use simple fluorescent tracers to allow wide-scale visualization of severely damaged vessels and determine whether such vascular disruption colocalized with regions of severe parenchymal injury. Severe vascular disruption and ischemic injury was produced in adult Sprague Dawley rats by transient occlusion of the middle cerebral artery for 1, 2, 4, or 8 hours, followed by 30 minutes of reperfusion. Fluorescein isothiocyanate-dextran (2 MDa) was injected intravenously before occlusion. After perfusion-fixation, brain sections were processed for ultrastructure or fluorescence imaging. We identified early evidence of tissue damage with Fluoro-Jade staining of dying cells. With increasing ischemia duration, greater quantities of high molecular weight dextran-fluorescein isothiocyanate invaded and marked ischemic regions in a characteristic pattern, appearing first in the medial striatum, spreading to the lateral striatum, and finally involving cortex; maximal injury was seen in the mid-parietal areas, consistent with the known ischemic zone in this model. The regional distribution of the severe vascular disruption correlated with the distribution of 24-hour 2,3,5-triphenyltetrazolium chloride pallor (r=0.75; P<0.05) and the cell death marker Fluoro-Jade (r=0.86; P<0.05). Ultrastructural examination showed significantly increased areas of swollen astrocytic foot process and swollen mitochondria in regions of high compared to low leakage, and compared to contralateral homologous regions (ANOVA P<0.01). Dextran extravasation into the basement membrane and surrounding tissue increased significantly from 2 to 8 hours of

  14. Method of measuring directed electron velocities in flowing plasma using the incoherent regions of laser scattering

    International Nuclear Information System (INIS)

    Jacoby, B.A.; York, T.M.

    1979-02-01

    With the presumption that a shifted Maxwellian velocity distribution adequately describes the electrons in a flowing plasma, the details of a method to measure their directed velocity are described. The system consists of a ruby laser source and two detectors set 180 0 from each other and both set at 90 0 with respect to the incident laser beam. The lowest velocity that can be determined by this method depends on the electron thermal velocity. The application of this diagnostic to the measurement of flow velocities in plasma being lost from the ends of theta-pinch devices is described

  15. Numerical study on plasma flow control to enhance the aerodynamic characteristic of the aerofoil on propeller root region

    International Nuclear Information System (INIS)

    Cheng Yufeng; Nie Wansheng; Che Xueke

    2012-01-01

    Based on the body force aerodynamic actuation mechanism of dielectric barrier discharge (DBD) plasma, the effect of DBD plasma flow control to enhance the aerodynamic characteristics of aerofoil on propeller root region under the negative angle of attack condition was numerically studied at two kinds of actuator location schemes. The results show that the plasma induce body force imparted by the actuator located at down surface of the aerofoil is bigger than that imparted by the actuator located at front or behind of the aerofoil. When DBD actuator is located at down surface of the aerofoil, the separate flow phenomenon can be entirely restrained, but the negative thrust of propeller will increase, so the torque of propeller will decrease. When the actuator is located at front and behind of the aerofoil, the thrust generated by the aerofoil of propeller root region under the negative angle of attack condition will increase, but the separate flow phenomenon cannot be restrained, so the torque of propeller will also increase. (authors)

  16. Duloxetine Plasma Concentrations and Its Effectiveness in the Treatment of Nonorganic Chronic Pain in the Orofacial Region.

    Science.gov (United States)

    Kobayashi, Yuka; Nagashima, Wataru; Tokura, Tatsuya; Yoshida, Keizo; Umemura, Eri; Miyauchi, Tomoya; Arao, Munetaka; Ito, Mikiko; Kimura, Hiroyuki; Kurita, Kenichi; Ozaki, Norio

    The purpose of this study was to examine the relationship between the pain-relieving effects of duloxetine and its plasma concentrations in patients with burning mouth syndrome and atypical odontalgia characterized by chronic nonorganic pain in the orofacial region. We administered duloxetine to 77 patients diagnosed as having burning mouth syndrome or atypical odontalgia for 12 weeks. The initial dose of duloxetine was established as 20 mg/d and was increased to 40 mg/d after week 2. We evaluated pain using the visual analog scale and depressive symptoms using the Structured Interview Guide for the Hamilton Depression Rating Scale at weeks 0, 2, 4, 6, 8, 10, and 12 and measured plasma concentrations of duloxetine 12 weeks after the start of its administration. Visual analog scale scores were significantly lower 12 weeks after than at the start of the administration of duloxetine (paired t test, t = 6.65, P pain in patients with chronic nonorganic pain in the orofacial region. However, no relationship was observed between its pain-relieving effects and plasma concentrations.

  17. Production of low-density plasma by coaxially segmented rf discharge for void-free dusty cloud in microgravity experiments

    International Nuclear Information System (INIS)

    Suzukawa, Wataru; Ikada, Reijiro; Tanaka, Yasuhiro; Iizuka, Satoru

    2006-01-01

    A technique is presented for producing a low density plasma by introducing a coaxially segmented parallel-plate radio-frequency discharge for void-free dusty-cloud formation. Main plasma for the dusty plasma experiment is produced in a central core part of the parallel-plate discharge, while a plasma for igniting the core plasma discharge is produced in the periphery region surrounding the core plasma. The core plasma density can be markedly decreased to reduce the ion drag force, which is important for a formation of void-free dusty cloud under microgravity

  18. ULF waves and plasma stability in different regions of the magnetosheath

    Science.gov (United States)

    Soucek, Jan; Escoubet, C. Philippe; Grison, Benjamin

    2016-04-01

    We present a statistical study of the occurrence and properties of ultra low frequency waves in the magnetosheath and interpret the results in terms of the competition of mirror and Alfvén-ion-cyclotron (AIC) instabilities. Both mirror and AIC waves are generated in high beta plasma of the magnetosheath when ion temperature anisotropy exceeds the threshold of the respective instabilities. These waves are frequently observed in the terrestrial and planetary magnetosheaths, but their distribution within the magnetosheath is inhomogeneous and their character varies as a function of location, local and upstream plasma parameters. We studied the spatial distribution of the two wave modes in the magnetosheath together with the local plasma parameters important for the stability of ULF waves. This analysis was performed on a dataset of all magnetosheath crossings observed by Cluster spacecraft over two years. For each observation we used bow shock, magnetopause and magnetosheath flow models to identify the relative position of the spacecraft with respect to magnetosheath boundaries and local properties of the upstream shock crossing. A strong dependence of parameters characterizing plasma stability and mirror/AIC wave occurrence on upstream ΘBn and MA is identified. The occurrence of mirror and AIC modes was compared against the respective instability thresholds and it was observed that AIC waves occurred nearly exclusively under mirror stable conditions. This is interpreted in terms of the different character of non-linear saturation of the two modes.

  19. Ionospheric electron acceleration by electromagnetic waves near regions of plasma resonances

    International Nuclear Information System (INIS)

    Villalon, E.

    1989-01-01

    Electron acceleration by electromagnetic fields propagating in the inhomogeneous ionospheric plasma is investigated. It is found that high-amplitude short wavelength electrostatic waves are generated by the incident electromagnetic fields that penetrate the radio window. These waves can very efficiently transfer their energy to the electrons if the incident frequency is near the second harmonic of the cyclotron frequency

  20. X-ray emitting hot plasma in solar active regions observed by the SphinX spectrometer

    Science.gov (United States)

    Miceli, M.; Reale, F.; Gburek, S.; Terzo, S.; Barbera, M.; Collura, A.; Sylwester, J.; Kowalinski, M.; Podgorski, P.; Gryciuk, M.

    2012-08-01

    Aims: The detection of very hot plasma in the quiescent corona is important for diagnosing heating mechanisms. The presence and the amount of such hot plasma is currently debated. The SphinX instrument on-board the CORONAS-PHOTON mission is sensitive to X-ray emission of energies well above 1 keV and provides the opportunity to detect the hot plasma component. Methods: We analysed the X-ray spectra of the solar corona collected by the SphinX spectrometer in May 2009 (when two active regions were present). We modelled the spectrum extracted from the whole Sun over a time window of 17 days in the 1.34-7 keV energy band by adopting the latest release of the APED database. Results: The SphinX broadband spectrum cannot be modelled by a single isothermal component of optically thin plasma and two components are necessary. In particular, the high statistical significance of the count rates and the accurate calibration of the spectrometer allowed us to detect a very hot component at ~7 million K with an emission measure of ~2.7 × 1044 cm-3. The X-ray emission from the hot plasma dominates the solar X-ray spectrum above 4 keV. We checked that this hot component is invariably present in both the high and low emission regimes, i.e. even excluding resolvable microflares. We also present and discuss the possibility of a non-thermal origin (which would be compatible with a weak contribution from thick-target bremsstrahlung) for this hard emission component. Conclusions: Our results support the nanoflare scenario and might confirm that a minor flaring activity is ever-present in the quiescent corona, as also inferred for the coronae of other stars.

  1. Interferometric investigation methods of plasma spatial characteristics on stellarators and tokamaks in submillimeter region

    International Nuclear Information System (INIS)

    Berezhnyj, V.L.; Kononenko, V.I.; Epishin, V.A.; Topkov, A.N.

    1992-01-01

    The review of interferometric methods of plasma investigation in the wave submillimeter range is given. The diagnostic schemes in stellarators and tokamaks designed for experienced thermonuclear reactors and also the perspective ones, which are still out of practice, are shown. The methods of these diagnostics, their physical principles, the main possibilities and restrictions at changes of electron density, magnetic fields (currents) and their spatial distributions are described. 105 refs.; 9 figs.; 2 tables. (author)

  2. Study of emission process in hot, optically thin plasma: application to solar active regions

    International Nuclear Information System (INIS)

    Steenman-Clark, Lois.

    1983-06-01

    Analysis of soft X-ray got in hot and weak density plasmas, such as those in TOKAMAKS and in solar flares, needs a detailed knowledge of emission processes. In this work are presented spectroscopic diagnostics which can be deduced from such spectra analysis and results are applied to magnesium solar spectrum analysis. An important improvement is brought to collisional calculation corresponding to forbidden line populating. For this line, The relative importance of autoionizing states effect, called also resonance effect is studied [fr

  3. Opportunity's Surroundings on Sol 1687

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 360-degree view of the rover's surroundings on the 1,687th Martian day, or sol, of its surface mission (Oct. 22, 2008). Opportunity had driven 133 meters (436 feet) that sol, crossing sand ripples up to about 10 centimeters (4 inches) tall. The tracks visible in the foreground are in the east-northeast direction. Opportunity's position on Sol 1687 was about 300 meters southwest of Victoria Crater. The rover was beginning a long trek toward a much larger crater, Endeavour, about 12 kilometers (7 miles) to the southeast. This view is presented as a cylindrical projection with geometric seam correction.

  4. Methods of staining and visualization of sphingolipid enriched and non-enriched plasma membrane regions of Arabidopsis thaliana with fluorescent dyes and lipid analogues

    Directory of Open Access Journals (Sweden)

    Blachutzik Jörg O

    2012-08-01

    Full Text Available Abstract Background Sterols and Sphingolipids form lipid clusters in the plasma membranes of cell types throughout the animal and plant kingdoms. These lipid domains provide a medium for protein signaling complexes at the plasma membrane and are also observed to be principal regions of membrane contact at the inception of infection. We visualized different specific fluorescent lipophilic stains of the both sphingolipid enriched and non-sphingolipid enriched regions in the plasma membranes of live protoplasts of Arabidopsis thaliana. Results Lipid staining protocols for several fluorescent lipid analogues in plants are presented. The most emphasis was placed on successful protocols for the single and dual staining of sphingolipid enriched regions and exclusion of sphingolipid enriched regions on the plasma membrane of Arabidopsis thaliana protoplasts. A secondary focus was placed to ensure that these staining protocols presented still maintain cell viability. Furthermore, the protocols were successfully tested with the spectrally sensitive dye Laurdan. Conclusion Almost all existing staining procedures of the plasma membrane with fluorescent lipid analogues are specified for animal cells and tissues. In order to develop lipid staining protocols for plants, procedures were established with critical steps for the plasma membrane staining of Arabidopsis leaf tissue and protoplasts. The success of the plasma membrane staining protocols was additionally verified by measurements of lipid dynamics by the fluorescence recovery after photobleaching technique and by the observation of new phenomena such as time dependent lipid polarization events in living protoplasts, for which a putative physiological relevance is suggested.

  5. The transcriptome and miRNome profiling of glioblastoma tissues and peritumoral regions highlights molecular pathways shared by tumors and surrounding areas and reveals differences between short-term and long-term survivors.

    Science.gov (United States)

    Fazi, Barbara; Felsani, Armando; Grassi, Luigi; Moles, Anna; D'Andrea, Daniel; Toschi, Nicola; Sicari, Daria; De Bonis, Pasquale; Anile, Carmelo; Guerrisi, Maria Giovanna; Luca, Emilia; Farace, Maria Giulia; Maira, Giulio; Ciafré, Silvia Anna; Mangiola, Annunziato

    2015-09-08

    Glioblastoma multiforme (GBM) is the most common and deadliest primary brain tumor, driving patients to death within 15 months after diagnosis (short term survivors, ST), with the exception of a small fraction of patients (long term survivors, LT) surviving longer than 36 months. Here we present deep sequencing data showing that peritumoral (P) areas differ from healthy white matter, but share with their respective frankly tumoral (C) samples, a number of mRNAs and microRNAs representative of extracellular matrix remodeling, TGFβ and signaling, of the involvement of cell types different from tumor cells but contributing to tumor growth, such as microglia or reactive astrocytes. Moreover, we provide evidence about RNAs differentially expressed in ST vs LT samples, suggesting the contribution of TGF-β signaling in this distinction too. We also show that the edited form of miR-376c-3p is reduced in C vs P samples and in ST tumors compared to LT ones. As a whole, our study provides new insights into the still puzzling distinction between ST and LT tumors, and sheds new light onto that "grey" zone represented by the area surrounding the tumor, which we show to be characterized by the expression of several molecules shared with the proper tumor mass.

  6. Effect of the resonant magnetic perturbation on the plasma parameters in COMPASS tokamak’s divertor region

    Science.gov (United States)

    Dimitrova, M.; Cahyna, P.; Peterka, M.; Hasan, E.; Popov, Tsv K.; Ivanova, P.; Vasileva, E.; Panek, R.; Cavalier, J.; Seidl, J.; Markovic, T.; Havlicek, J.; Dejarnac, R.; Weinzettl, V.; Hacek, P.; Tomes, M.; the COMPASS Team; the EUROfusion MST1 Team

    2018-02-01

    The resonant magnetic perturbation (RMP) has proven to be a useful way to suppress edge-localized modes that under certain conditions can damage the device by the large power fluxes carried from the bulk plasma to the wall. The effect of RMP on the L-mode plasma parameters in the divertor region of the COMPASS tokamak was studied using the array of 39 Langmuir probes embedded into the divertor target. The current-voltage (IV) probe characteristics were processed by the first-derivative probe technique to obtain the plasma potential and the electron energy distribution function (EEDF) which was approximated by a bi-Maxwellian EEDF with a low-energy (4-6 eV) fraction and a high-energy (11-35 eV) one, the both factions having similar electron density. Clear splitting was observed during the RMP pulse in the low-field-side scrape-off-layer profiles of the floating potential U fl and the ion saturation current density J sat; these two quantities were obtained both by direct continuous measurement and by evaluation of the IV characteristics of probes with swept bias. The negative peaks of U fl induced by RMP spatially overlaps with the local minima of J sat (and n e) rather than with its local maxima which is partly caused by the spatial variation of the plasma potential and partly by the changed shape of the EEDF. The effective temperature of the whole EEDF is not correlated with the negative peaks of U fl, and the profile of the parallel power flux density shows secondary maxima due to RMP which mimic those of J sat.

  7. Dynamic trapping of electrons in space plasmas

    International Nuclear Information System (INIS)

    Brenning, N.; Bohm, M.; Faelthammar, C.G.

    1989-12-01

    The neutralization of positive space charge is studied in a case where heavy positive ions are added to a limited region of length L in a collisionfree magnetized plasma. It is found that electrons which become accelerated towards the positive space charge can only achieve a partial neutralization: they overshoot, and the positive region becomes surrounded by negative space charges which screen the electric field from the surroundings. The process is studied both analytically and by computer simulations with consistent results: large positive potentials (U>>kT e /e) can be built up with respect to the surrounding plasma. In the process of growth, the potential maximum traps electrons in transit so that quasineutrality is maintained. The potential U is proportional to the ambient electron temperature and the square of the plasma density increase, but independent of both the ion injection rate and the length L. The process explains several features of the Porcupinge xenon beam injection experiment. It could also have importance for the electrodynamic coupling between plasmas of different densities, e.g. the injection of neutral clouds in the ionosphere of species that becomes rapidly photoionized, or penetration of dense plasma clouds from the solar wind into the magnetosphere. (31 refs.) (authors)

  8. Rocket in situ observation of equatorial plasma irregularities in the region between E and F layers over Brazil

    Directory of Open Access Journals (Sweden)

    S. Savio Odriozola

    2017-03-01

    Full Text Available A two-stage VS-30 Orion rocket was launched from the equatorial rocket launching station in Alcântara, Brazil, on 8 December 2012 soon after sunset (19:00 LT, carrying a Langmuir probe operating alternately in swept and constant bias modes. At the time of launch, ground equipment operated at equatorial stations showed rapid rise in the base of the F layer, indicating the pre-reversal enhancement of the F region vertical drift and creating ionospheric conditions favorable for the generation of plasma bubbles. Vertical profiles of electron density estimated from Langmuir probe data showed wave patterns and small- and medium-scale plasma irregularities in the valley region (100–300 km during the rocket upleg and downleg. These irregularities resemble those detected by the very high frequency (VHF radar installed at Jicamarca and so-called equatorial quasi-periodic echoes. We present evidence suggesting that these observations could be the first detection of this type of irregularity made by instruments onboard a rocket.

  9. In-Situ Measurement of Ionospheric E-Region Plasma Irregularities over Taiwan

    Directory of Open Access Journals (Sweden)

    Chi-Kuang Chao

    2012-01-01

    Full Text Available One ion trap (IT and one retarding potential analyzer (RPA onboard the Taiwan Sounding Rocket V (SR-V were launched to measure ionospheric plasma irregularities on 18 January 2006. After the fairing separated, voltage readings (VG1 of the first grid (G1 in the IT indicated abnormally high negative voltages appeared at the upleg between 83.7 and 120.1 km altitude for 19.7 seconds. It is postulated G1 had temporarily shorted out with the other two grids. Such the anomaly in the VG1 brought out the expansion of a plasma sheath around opening of the IT. More ions were attracted into the collector. Remarkable ion currents detected by the IT led to malfunctions of the RPA simultaneously. In this article, laboratory simulations and the International Reference Ionosphere model are performed to evaluate scale factors for the IT to the anomaly. The calibrated total ion concentration profile at the upleg indicates a peak density of the Es layer at 93.0 km altitude of about 6.9 × 103 # cm-3 with a thickness of 3.4 km. It is very similar to that at the downleg. It implies that the SR-V might encounter the same Es layer twice in a distance of 150 km away.

  10. Equatorial 150 km echoes and daytime F region vertical plasma drifts in the Brazilian longitude sector

    Directory of Open Access Journals (Sweden)

    F. S. Rodrigues

    2013-10-01

    Full Text Available Previous studies showed that conventional coherent backscatter radar measurements of the Doppler velocity of the so-called 150 km echoes can provide an alternative way of estimating ionospheric vertical plasma drifts during daytime hours (Kudeki and Fawcett, 1993; Chau and Woodman, 2004. Using observations made by a small, low-power 30 MHz coherent backscatter radar located in the equatorial site of São Luís (2.59° S, 44.21° W; −2.35° dip lat, we were able to detect and monitor the occurrence of 150 km echoes in the Brazilian sector. Using these measurements we estimated the local time variation of daytime vertical ionospheric drifts in the eastern American sector. Here, we present a few interesting cases of 150 km-echoes observations made by the São Luís radar and estimates of the diurnal variation of vertical drifts. These cases exemplify the variability of the vertical drifts in the Brazilian sector. Using same-day 150 km-echoes measurements made at the Jicamarca Radio Observatory in Peru, we also demonstrate the variability of the equatorial vertical drifts across the American sector. In addition to first estimates of the absolute vertical plasma drifts in the eastern American (Brazilian sector, we also present observations of abnormal drifts detected by the São Luís radar associated with the 2009 major sudden stratospheric warming event.

  11. Regard sur la participation de populations marginalisées à la recherche-action. Le cas des squatteurs en Ile-de-France The participation of Marginalised populations in research-action: a case study of squatters in the Ile-de-France region (Paris and surrounding region

    Directory of Open Access Journals (Sweden)

    Lionel Pourtau

    2011-05-01

    Full Text Available La recherche-action comporte deux caractéristiques principales : elle met en œuvre la collaboration entre plusieurs types d’acteurs et vise une transformation de la réalité sociale. Elle possède des forces et des faiblesses différentes de la recherche à objectif strictement cognitif. L’article rend compte d’une recherche-action menée par des sociologues, des intervenants sociaux et des populations vivant en squats en Ile-de-France. Les auteurs analysent les enjeux méthodologiques qui se sont posés sur ce terrain particulier relevant de la sociologie de la déviance. Ceux-ci sont liés, notamment, à la participation de chaque groupe d’acteurs aux différentes étapes de la recherche, à la présence d’intérêts différents portés par chacun d’entre eux, et à la conciliation entre les principes habituellement de rigueur dans l’enquête sociologique et les principes de la recherche-action.Research-Action has two main objectives: to allow different players to cooperate, and to transform social reality. This methodology has both the strengths and the weaknesses of strictly cognitive research. In this article, the authors discuss a research-action project which brought together sociologists, social workers and squatters from the Ile-de-France region (Paris and surrounding region. Methodological issues that arise specifically in the context of deviance are addressed, notably the participation of the different players at different stages of the research project, their different areas of interest, as well as the reconciliation between more conventional sociological research and the principles of research-action.

  12. Binaural Rendering in MPEG Surround

    Directory of Open Access Journals (Sweden)

    Kristofer Kjörling

    2008-04-01

    Full Text Available This paper describes novel methods for evoking a multichannel audio experience over stereo headphones. In contrast to the conventional convolution-based approach where, for example, five input channels are filtered using ten head-related transfer functions, the current approach is based on a parametric representation of the multichannel signal, along with either a parametric representation of the head-related transfer functions or a reduced set of head-related transfer functions. An audio scene with multiple virtual sound sources is represented by a mono or a stereo downmix signal of all sound source signals, accompanied by certain statistical (spatial properties. These statistical properties of the sound sources are either combined with statistical properties of head-related transfer functions to estimate “binaural parameters” that represent the perceptually relevant aspects of the auditory scene or used to create a limited set of combined head-related transfer functions that can be applied directly on the downmix signal. Subsequently, a binaural rendering stage reinstates the statistical properties of the sound sources by applying the estimated binaural parameters or the reduced set of combined head-related transfer functions directly on the downmix. If combined with parametric multichannel audio coders such as MPEG Surround, the proposed methods are advantageous over conventional methods in terms of perceived quality and computational complexity.

  13. Opportunity's Surroundings on Sol 1798 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 180-degree view of the rover's surroundings during the 1,798th Martian day, or sol, of Opportunity's surface mission (Feb. 13, 2009). North is on top. This view is presented as a polar projection with geometric seam correction. The rover had driven 111 meters (364 feet) southward on the preceding sol. Tracks from that drive recede northward in this view. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock.

  14. Opportunity's Surroundings After Sol 1820 Drive (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). This view is presented as a polar projection with geometric seam correction. North is at the top. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock.

  15. Opportunity's Surroundings on Sol 1798 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 180-degree view of the rover's surroundings during the 1,798th Martian day, or sol, of Opportunity's surface mission (Feb. 13, 2009). North is on top. This view is presented as a vertical projection with geometric seam correction. The rover had driven 111 meters (364 feet) southward on the preceding sol. Tracks from that drive recede northward in this view. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock.

  16. Opportunity's Surroundings After Sol 1820 Drive (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). This view is presented as a vertical projection with geometric seam correction. North is at the top. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock.

  17. Opportunity's Surroundings After Sol 1820 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). South is at the center; north at both ends. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  18. Plasma instabilities in the ionosphere at the crest of anomaly region

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Shivalika, E-mail: shivalikasarkar@gmail.com [Department of Education in Science and Mathematics, Regional Institute of Education, Bhopal – 462013 (India); Tiwari, Sunita, E-mail: suni-tiwari@yahoo.co.in [LNCT, Kalchuri Nagar, Raisen Road, Bhopal (India); Gwal, A. K., E-mail: ashok.gwal@gmail.com [Department of Physics, Barkatullah University, Bhopal-462026 (India)

    2015-07-31

    Comparison of the in situ density fluctuations measured by the DEMETER satellite with ground based GPS receiver measurements at the equatorial anomaly station Bhopal [geographic coordinates (23.2°N, 77.6°E); geomagnetic coordinates (14.29° N, 151.12°E)] for the low solar activity year, 2005, are presented in this paper. The Langmuir Probe experiment and Plasma Analyzer onboard DEMETER measure the electron and ion densities respectively. It is interesting to note that in situ density fluctuations observed on magnetic flux tubes that pass over Bhopal can be used as indicator of ionospheric scintillations at that site. Many cases of density fluctuations and associated scintillations have been observed during descending low solar activity period.

  19. Theoretical and experimental zonal drift velocities of the ionospheric plasma bubbles over the Brazilian region

    Science.gov (United States)

    Arruda, Daniela C. S.; Sobral, J. H. A.; Abdu, M. A.; Castilho, Vivian M.; Takahashi, H.; Medeiros, A. F.; Buriti, R. A.

    2006-01-01

    This work presents equatorial ionospheric plasma bubble zonal drift velocity observations and their comparison with model calculations. The bubble zonal velocities were measured using airglow OI630 nm all-sky digital images and the model calculations were performed taking into account flux-tube integrated Pedersen conductivity and conductivity weighted neutral zonal winds. The digital images were obtained from an all-sky imaging system operated over the low-latitude station Cachoeira Paulista (Geogr. 22.5S, 45W, dip angle 31.5S) during the period from October 1998 to August 2000. Out of the 138 nights of imager observation, 29 nights with the presence of plasma bubbles are used in this study. These 29 nights correspond to geomagnetically rather quiet days (∑K P hours, the calculated zonal drift velocities were found to be larger than the experimental values. The best matching between the calculated and observed zonal velocities were seen to be for a few hours around midnight. The model calculation showed two humps around 20 LT and 24 LT that were not present in the data. Average decelerations obtained from linear regression between 20 LT and 24 LT were found to be: (a) Spring 1998, -8.61 ms -1 h -1; (b) Summer 1999, -0.59 ms -1 h -1; (c) Spring 1999, -11.72 ms -1 h -1; and (d) Summer 2000, -8.59 ms -1 h -1. Notice that Summer and Winter here correspond to southern hemisphere Summer and Winter, not northern hemisphere.

  20. Comparison of the dynamical processes in plasma turbulence observed in the high- and low-β regions of the terrestrial foreshock

    International Nuclear Information System (INIS)

    Coca, D.; Balikhin, M.; Billings, S.

    2001-01-01

    This paper highlights the fact that the dynamical processes that characterise plasma turbulence observed in the high-β region of the terrestrial foreshock are significantly different from the dynamical processes identified in the low-β region. The study is based on a time-domain model identified from measurements taken by AMPTE-UKS and AMPTE-IRM satellites. (author)

  1. Comparison of the dynamical processes in plasma turbulence observed in the high- and low-{beta} regions of the terrestrial foreshock

    Energy Technology Data Exchange (ETDEWEB)

    Coca, D.; Balikhin, M.; Billings, S

    2001-06-01

    This paper highlights the fact that the dynamical processes that characterise plasma turbulence observed in the high-{beta} region of the terrestrial foreshock are significantly different from the dynamical processes identified in the low-{beta} region. The study is based on a time-domain model identified from measurements taken by AMPTE-UKS and AMPTE-IRM satellites. (author)

  2. INTERSTELLAR MAGNETIC FIELD SURROUNDING THE HELIOPAUSE

    International Nuclear Information System (INIS)

    Whang, Y. C.

    2010-01-01

    This paper presents a three-dimensional analytical solution, in the limit of very low plasma β-ratio, for the distortion of the interstellar magnetic field surrounding the heliopause. The solution is obtained using a line dipole method that is the integration of point dipole along a semi-infinite line; it represents the magnetic field caused by the presence of the heliopause. The solution allows the variation of the undisturbed magnetic field at any inclination angle. The heliosphere is considered as having blunt-nosed geometry on the upwind side and it asymptotically approaches a cylindrical geometry having an open exit for the continuous outflow of the solar wind on the downwind side. The heliopause is treated as a magnetohydrodynamic tangential discontinuity; the interstellar magnetic field lines at the boundary are tangential to the heliopause. The interstellar magnetic field is substantially distorted due to the presence of the heliopause. The solution shows the draping of the field lines around the heliopause. The magnetic field strength varies substantially near the surface of the heliopause. The effect on the magnetic field due to the presence of the heliopause penetrates very deep into the interstellar space; the depth of penetration is of the same order of magnitude as the scale length of the heliosphere.

  3. Construction of a series of congenic mice with recombinant chromosome 1 regions surrounding the genetic loci for resistance to intracellular parasites (Ity, Lsh, and Bcg), DNA repair responses (Rep-1), and the cytoskeletal protein villin (Vil).

    Science.gov (United States)

    Mock, B A; Holiday, D L; Cerretti, D P; Darnell, S C; O'Brien, A D; Potter, M

    1994-01-01

    The interval of mouse chromosome 1 extending from Idh-1 to Pep-3 harbors the natural resistance gene Ity/Lsh/Bcg; it controls the outcome of infection with Salmonella typhimurium, Leishmania donovani, and several Mycobacterium species. This region also contains a DNA repair gene, Rep-1, which determines the rapidity with which double-strand breaks in chromatin are repaired. BALB/cAnPt and DBA/2N mice differ in their phenotypic expression of these genes. To generate appropriate strains of mice for the study of these genes, a series of 10 C.D2 congenic strains recombinant across a 28-centimorgan interval of mouse chromosome 1 extending from Idh-1 to Pep-3 were derived from crosses of the C.D2-Idh-1 Pep-3 congenic strain back to BALB/cAn. Analyses of these recombinant strains will allow the correlation of biological-immunological phenotypes with defined genetic regions.

  4. Landscape Archaeology in the surrounding of «Lauro»: A micro-regional approach to Roman territorial shaping in a north-eastern sector of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Arnau GARCÍA MOLSOSA

    2015-11-01

    Full Text Available The link between the place-name Lauro and the ancient history of the eastern part of Vallès region (Barcelona is a constant throughout historiography. In this paper, this ancient Lauro serves as a guide to present the results of a research conducted in a small area, which due to archaeological data complexity has been of great interest to study the dynamics of territorial structuration in one of the first rural areas conquered by Rome outside the Italian peninsula.From Landscape Archaeology conceptual and methodological tools, extensive and intensive archaeological surveys have been developed. The collected materials and the documented structural remains have allowed us to define settlement and human occupation in a chronology ranging from the development of indigenous (Iberian societies to the consolidation of the Roman Empire –ivth bc-iith ad–.The results of these works set out the elements to analyse the impact of Roman conquest in settlement evolution at a micro-regional scale. The studied area may represent a model to contrast in other regions and to discuss in future works.

  5. A YAC contig and an EST map in the pericentromeric region of chromosome 13 surrounding the loci for neurosensory nonsyndromic deafness (DFNB1 and DFNA3) and Limb-Girdle muscular dystrophy type 2C (LGMD2C)

    Energy Technology Data Exchange (ETDEWEB)

    Guilford, P.; Crozet, F.; Blanchard, S. [Institut Pasteur, Paris (France)] [and others

    1995-09-01

    Two forms of inherited childhood nonsyndromic deafness (DFNB1 and DFNA3) and a Duchenne-like form of progressive muscular dystrophy (LGMD2C) have been mapped to the pericentromeric region of chromosome 13. To clone the genes responsible for these diseases we constructed a yeast artificial chromosome (YAC) contig spanning an 8-cM region between the polymorphic markers D13S221. The contig comprises 24 sequence-tagged sites, among which 15 were newly obtained. This contig allowed us to order the polymorphic markers centromere- D13S175-D13S141-D13S143-D13S115-AFM128yc1-D13S292-D13S283-AFM323vh5-D13S221-telomere. Eight expressed sequence tags, previously assigned to 13q11-q12 (D13S182E, D13S183E, D13S502E, D13S504E, D13S505E, D13S837E, TUBA2, ATP1AL1), were localized on the YAC contig. YAC screening of a cDNA library derived from mouse cochlea allowed us to identify an {alpha}-tubulin gene (TUBA2) that was subsequently precisely mapped within the candidate region. 36 refs., 2 figs., 2 tabs.

  6. 30 MHz radar observations of artificial E region field-aligned plasma irregularities

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2008-02-01

    Full Text Available Artificial E region field aligned irregularities (FAIs have been observed during heating experiments at the HAARP facility using a new 30 MHz coherent scatter radar imager deployed near Homer, Alaska. Irregularities were observed during brief experiments on three quiet days in July and August, 2007, when the daytime E region critical frequency was close to 3 MHz. Irregularities were consistently generated and detected during experiments with O-mode HF pumping on zenith with a 1-min on, 1-min off CW modulation. The scattering cross sections, rise, and fall times of the echoes were observed as well as their spectral properties. Results were found to be mainly in agreement with observations from other mid- and high-latitude sites with some discrepancies. Radar images of the irregularity-filled volume on one case exhibited clear variations in backscatter power and Doppler shift across the volume. The images furthermore show the emergence of a small irregularity-filled region to the south southwest of the main region in the approximate direction of magnetic zenith.

  7. Eosinophils may play regionally disparate roles in influencing IgA(+) plasma cell numbers during large and small intestinal inflammation.

    Science.gov (United States)

    Forman, Ruth; Bramhall, Michael; Logunova, Larisa; Svensson-Frej, Marcus; Cruickshank, Sheena M; Else, Kathryn J

    2016-05-31

    Eosinophils are innate immune cells present in the intestine during steady state conditions. An intestinal eosinophilia is a hallmark of many infections and an accumulation of eosinophils is also observed in the intestine during inflammatory disorders. Classically the function of eosinophils has been associated with tissue destruction, due to the release of cytotoxic granule contents. However, recent evidence has demonstrated that the eosinophil plays a more diverse role in the immune system than previously acknowledged, including shaping adaptive immune responses and providing plasma cell survival factors during the steady state. Importantly, it is known that there are regional differences in the underlying immunology of the small and large intestine, but whether there are differences in context of the intestinal eosinophil in the steady state or inflammation is not known. Our data demonstrates that there are fewer IgA(+) plasma cells in the small intestine of eosinophil-deficient ΔdblGATA-1 mice compared to eosinophil-sufficient wild-type mice, with the difference becoming significant post-infection with Toxoplasma gondii. Remarkably, and in complete contrast, the absence of eosinophils in the inflamed large intestine does not impact on IgA(+) cell numbers during steady state, and is associated with a significant increase in IgA(+) cells post-infection with Trichuris muris compared to wild-type mice. Thus, the intestinal eosinophil appears to be less important in sustaining the IgA(+) cell pool in the large intestine compared to the small intestine, and in fact, our data suggests eosinophils play an inhibitory role. The dichotomy in the influence of the eosinophil over small and large intestinal IgA(+) cells did not depend on differences in plasma cell growth factors, recruitment potential or proliferation within the different regions of the gastrointestinal tract (GIT). We demonstrate for the first time that there are regional differences in the requirement of

  8. Solar wind parameters responsible for the plasma injection into the magnetospheric ring current region

    International Nuclear Information System (INIS)

    Bobrov, M.S.

    1977-01-01

    Solar wind effect on the magnetospheric ring-current region has been considered. The correlations with solar wind parameters of the magnitude qsub(o) proportional to the total energy of particles being injected into the magnetospheric ring-current region per one hour are studied statistically and by comparison of time variations. The data on 8 sporadic geomagnetic storms of various intensity, from moderate to very severe one, are used. It is found that qsub(o) correlates not only with the magnitude and the direction of the solar-wind magnetic field component normal to the ecliptic plane, Bsub(z), but also with the variability, sigmasub(B), of the total magnetic-field strength vector. The solar-wind flux velocity ν influences the average storm intensity but the time variations of ν during any individual storm do not correlate with those of qsub(o)

  9. Elevated uptake of plasma macromolecules by regions of arterial wall predisposed to plaque instability in a mouse model.

    Directory of Open Access Journals (Sweden)

    Zahra Mohri

    Full Text Available Atherosclerosis may be triggered by an elevated net transport of lipid-carrying macromolecules from plasma into the arterial wall. We hypothesised that whether lesions are of the thin-cap fibroatheroma (TCFA type or are less fatty and more fibrous depends on the degree of elevation of transport, with greater uptake leading to the former. We further hypothesised that the degree of elevation can depend on haemodynamic wall shear stress characteristics and nitric oxide synthesis. Placing a tapered cuff around the carotid artery of apolipoprotein E -/- mice modifies patterns of shear stress and eNOS expression, and triggers lesion development at the upstream and downstream cuff margins; upstream but not downstream lesions resemble the TCFA. We measured wall uptake of a macromolecular tracer in the carotid artery of C57bl/6 mice after cuff placement. Uptake was elevated in the regions that develop lesions in hyperlipidaemic mice and was significantly more elevated where plaques of the TCFA type develop. Computational simulations and effects of reversing the cuff orientation indicated a role for solid as well as fluid mechanical stresses. Inhibiting NO synthesis abolished the difference in uptake between the upstream and downstream sites. The data support the hypothesis that excessively elevated wall uptake of plasma macromolecules initiates the development of the TCFA, suggest that such uptake can result from solid and fluid mechanical stresses, and are consistent with a role for NO synthesis. Modification of wall transport properties might form the basis of novel methods for reducing plaque rupture.

  10. INFERENCE OF HEATING PROPERTIES FROM “HOT” NON-FLARING PLASMAS IN ACTIVE REGION CORES. II. NANOFLARE TRAINS

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, W. T.; Bradshaw, S. J. [Department of Physics and Astronomy, Rice University, Houston, TX 77251-1892 (United States); Cargill, P. J., E-mail: will.t.barnes@rice.edu, E-mail: stephen.bradshaw@rice.edu, E-mail: p.cargill@imperial.ac.uk [Space and Atmospheric Physics, The Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)

    2016-12-20

    Despite its prediction over two decades ago, the detection of faint, high-temperature (“hot”) emission due to nanoflare heating in non-flaring active region cores has proved challenging. Using an efficient two-fluid hydrodynamic model, this paper investigates the properties of the emission expected from repeating nanoflares (a nanoflare train) of varying frequency as well as the separate heating of electrons and ions. If the emission measure distribution (EM(T)) peaks at T = T{sub m} , we find that EM(T{sub m}) is independent of details of the nanoflare train, and EM(T) above and below T{sub m} reflects different aspects of the heating. Below T{sub m} , the main influence is the relationship of the waiting time between successive nanoflares to the nanoflare energy. Above T{sub m}, power-law nanoflare distributions lead to an extensive plasma population not present in a mono-energetic train. Furthermore, in some cases, characteristic features are present in EM(T). Such details may be detectable given adequate spectral resolution and a good knowledge of the relevant atomic physics. In the absence of such resolution we propose some metrics that can be used to infer the presence of “hot” plasma.

  11. Lateral mobility of plasma membrane lipids in Xenopus eggs: Regional differences related to animal/vegetal polarity become extreme upon fertilization

    OpenAIRE

    Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van; Tetteroo, P.A.T.; Tertoolen, L.G.J.; Laat, S.W. de

    1984-01-01

    Regional differences in the lateral mobility properties of plasma membrane lipids have been studied in unfertilized and fertilizedxaqpus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein-labeled fatty acids HEDAF (5-(N-hexadecanoyl)-aminofluorescein) and TEDAF (5-(N-tetradecanoyl)-aminofluorescein) appear to partition into the plasma membrane. Under all experimental conditions used these molecules show par...

  12. E-region decameter-scale plasma waves observed by the dual TIGER HF radars

    Directory of Open Access Journals (Sweden)

    B. A. Carter

    2009-01-01

    Full Text Available The dual Tasman International Geospace Environment Radar (TIGER HF radars regularly observe E-region echoes at sub-auroral magnetic latitudes 58°–60° S including during geomagnetic storms. We present a statistical analysis of E-region backscatter observed in a period of ~2 years (late 2004–2006 by the TIGER Bruny Island and Unwin HF radars, with particular emphasis on storm-time backscatter. It is found that the HF echoes normally form a 300-km-wide band at ranges 225–540 km. In the evening sector during geomagnetic storms, however, the HF echoes form a curved band joining to the F-region band at ~700 km. The curved band lies close to the locations where the geometric aspect angle is zero, implying little to no refraction during geomagnetic storms, which is an opposite result to what has been reported in the past. The echo occurrence, Doppler velocity, and spectral width of the HF echoes are examined in order to determine whether new HF echo types are observed at sub-auroral latitudes, particularly during geomagnetic storms. The datasets of both TIGER radars are found to be dominated by low-velocity echoes. A separate population of storm-time echoes is also identified within the datasets of both radars with most of these echoes showing similar characteristics to the low-velocity echo population. The storm-time backscatter observed by the Bruny Island radar, on the other hand, includes near-range echoes (r<405 km that exhibit some characteristics of what has been previously termed the High Aspect angle Irregularity Region (HAIR echoes. We show that these echoes appear to be a storm-time phenomenon and further investigate this population by comparing their Doppler velocity with the simultaneously measured F- and E-region irregularity velocities. It is suggested that the HAIR-like echoes are observed only by HF radars with relatively poor geometric aspect angles when electron density is low and when the electric field is particularly

  13. Magnetic structure in the entrance region of spheromaks sustained by a magnetized coaxial plasma gun under long pulse operation

    International Nuclear Information System (INIS)

    Amemiya, Naoyuki; Takaichi, Kazuaki; Katsurai, Makoto

    1989-01-01

    The magnetic structure in coaxial-gun-sustained spheromaks has been investigated. The plasma gun has been operated with a small axial/radial bias magnetic flux as compared to the azimuthal magnetic flux produced by the discharge current. Stronger magnetic field is observed in the entrance region (ER) than in the flux conserver (FC). In both ER and FC, the magnetic structure is nearly axisymmetric. The axial magnetic field in ER is amplified up to about sixteen times as large as the bias magnetic field. This amplification is limited by the drastic change in the magnetic structure, which occurs when the discharge current becomes very large. The magnetic structure before the drastic change is interpreted with the Bessel function model. The μ estimation shows that the magnetic structure is mainly determined by the boundary geometry, not by the external magnetic flux and current. (author)

  14. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  15. Surrounding rock stress analysis of underground high level waste repository

    International Nuclear Information System (INIS)

    Liu Wengang; Wang Ju; Wang Guangdi

    2006-01-01

    During decay of nuclear waste, enormous energy was released, which results in temperature change of surrounding rock of depository. Thermal stress was produced because thermal expansion of rock was controlled. Internal structure of surrounding rock was damaged and strength of rock was weakened. So, variation of stress was a dynamic process with the variation of temperature. BeiShan region of Gansu province was determined to be the depository field in the future, it is essential to make research on granite in this region. In the process of experiment, basic physical parameters of granite were analyzed preliminary with MTS. Long range temperature and stress filed was simulated considering the damage effect of surrounding rock, and rules of temperature and stress was achieved. (authors)

  16. Regional potentiometric-surface map of the Great Basin carbonate and alluvial aquifer system in Snake Valley and surrounding areas, Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada

    Science.gov (United States)

    Gardner, Philip M.; Masbruch, Melissa D.; Plume, Russell W.; Buto, Susan G.

    2011-01-01

    Water-level measurements from 190 wells were used to develop a potentiometric-surface map of the east-central portion of the regional Great Basin carbonate and alluvial aquifer system in and around Snake Valley, eastern Nevada and western Utah. The map area covers approximately 9,000 square miles in Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada. Recent (2007-2010) drilling by the Utah Geological Survey and U.S. Geological Survey has provided new data for areas where water-level measurements were previously unavailable. New water-level data were used to refine mapping of the pathways of intrabasin and interbasin groundwater flow. At 20 of these locations, nested observation wells provide vertical hydraulic gradient data and information related to the degree of connection between basin-fill aquifers and consolidated-rock aquifers. Multiple-year water-level hydrographs are also presented for 32 wells to illustrate the aquifer system's response to interannual climate variations and well withdrawals.

  17. A qualitative study of attitudes and values surrounding stillbirth and neonatal mortality among grandmothers, mothers, and unmarried girls in rural Amhara and Oromiya regions, Ethiopia: unheard souls in the backyard.

    Science.gov (United States)

    Sisay, Mitike Molla; Yirgu, Robel; Gobezayehu, Abebe Gebremariam; Sibley, Lynn M

    2014-01-01

    In Ethiopia, neonatal mortality and stillbirth are high and underreported. This study explored values related to neonatal mortality and stillbirth and the visibility of these deaths in rural Ethiopia among 3 generations of women. We conducted a qualitative study in 6 rural districts of the Oromiya and Amhara regional states during May 2012. We included 30 focus groups representing grandmothers, married women (mothers), and unmarried girls in randomly selected kebeles (villages). Until the 40th day of life, neonates are considered to be strangers to the community (not human). Their deaths are not talked about; they are buried in the house or in the backyard. Mothers are forbidden to mourn their loss lest they offend God and bring on future neonatal losses. Women who repeatedly lose their neonates may be blamed, mistreated, and dishonored through divorce. Neonatal death and stillbirth are attributed to supernatural powers, although some women and girls associate these deaths with poverty and lack of education. The desire for increased visibility of neonatal death is mixed. Unlike the grandmothers and unmarried girls, most of the married women want death to be visible to draw the attention of policy makers. Women prefer home birth and consider themselves lucky to be able to give birth at home. At present, there is no national vital registration system. Neonatal death and stillbirth are hidden and the magnitude is likely underrepresented. The delayed recognition of personhood, attribution of death to supernatural causes, social repercussions for women who experience a pregnancy loss, preference for home birth, and lack of a vital registration system all contribute to the invisibility of perinatal deaths. Increasing the visibility of (and counting) these deaths may require multifaceted behavior-change interventions. © 2014 by the American College of Nurse-Midwives.

  18. Translation of an FRC plasma into a quasi-spherical confinement region

    International Nuclear Information System (INIS)

    Sekiguchi, Jun'ichi; Asai, Tomohiko; Takahashi, Tsutomu; Takahashi, Toshiki

    2014-01-01

    Translation of a Field-Reversed Configuration (FRC) into a quasi-spherical confinement region with super-alfvenic translation speed has been successfully conducted. Translation speed can be controlled in the range from 80 to 150 km/s by changing statically filled gas pressure. The translated FRC experiences radial decompression process rapidly when it enters into the confinement chamber. The separatrix shape of translated FRC is controlled through the translation process. Especially, in the case of FRC translation into deuterium gas atmosphere, elongation of the FRC is roughly unity. It indicates possible application of center solenoid onto the high-beta compact torus of FRC. Also, as a new finding, a rotational instability with an n=2 deformation has been observed in the translated FRC. (author)

  19. Faraday rotation measure variations in the Cygnus region and the spectrum of interstellar plasma turbulence

    Science.gov (United States)

    Lazio, T. Joseph; Spangler, Steven R.; Cordes, James M.

    1990-01-01

    Linear polarization observations were made of eight double-lobed radio galaxies viewed through the galactic plane in the Cygnus region. These observations have been used to determine intra- and intersource rotation measure differences; in some cases, unambiguous rotation measures have been extracted. The rotation measures are dominated by foreground magnetoionic material. The differences in rotation measure between pairs of sources correlate with angular separation for separations from 10 arcsec to 1.5 deg. These rotation measure fluctuations are consistent with a model in which the electron density varies on roughly 0.1-200 pc scales. The amplitudes of these variations are, in turn, consistent with those electron density variations that cause diffractive interstellar scattering on scales less than 10 to the 11th cm.

  20. Artificial E-region field-aligned plasma irregularities generated at pump frequencies near the second electron gyroharmonic

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2009-07-01

    Full Text Available E region ionospheric modification experiments have been performed at HAARP using pump frequencies about 50 kHz above and below the second electron gyroharmonic frequency. Artificial E region field-aligned plasma density irregularities (FAIs were created and observed using the imaging coherent scatter radar near Homer, Alaska. Echoes from FAIs generated with pump frequencies above and below 2Ωe did not appear to differ significantly in experiments conducted on summer afternoons in 2008, and the resonance instability seemed to be at work in either case. We argue that upper hybrid wave trapping and resonance instability at pump frequencies below the second electron gyroharmonic frequency are permitted theoretically when the effects of finite parallel wavenumbers are considered. Echoes from a sporadic E layer were observed to be somewhat weaker when the pump frequency was 50 kHz below the second electron gyroharmonic frequency. This may indicate that finite parallel wavenumbers are inconsistent with wave trapping in thin sporadic E ionization layers.

  1. Artificial E-region field-aligned plasma irregularities generated at pump frequencies near the second electron gyroharmonic

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2009-07-01

    Full Text Available E region ionospheric modification experiments have been performed at HAARP using pump frequencies about 50 kHz above and below the second electron gyroharmonic frequency. Artificial E region field-aligned plasma density irregularities (FAIs were created and observed using the imaging coherent scatter radar near Homer, Alaska. Echoes from FAIs generated with pump frequencies above and below 2Ωe did not appear to differ significantly in experiments conducted on summer afternoons in 2008, and the resonance instability seemed to be at work in either case. We argue that upper hybrid wave trapping and resonance instability at pump frequencies below the second electron gyroharmonic frequency are permitted theoretically when the effects of finite parallel wavenumbers are considered. Echoes from a sporadic E layer were observed to be somewhat weaker when the pump frequency was 50 kHz below the second electron gyroharmonic frequency. This may indicate that finite parallel wavenumbers are inconsistent with wave trapping in thin sporadic E ionization layers.

  2. The Trees that surround us

    Science.gov (United States)

    Costa, M. E. G.; Rodrigues, M. A. S.

    2012-04-01

    In our school the activities linked with sciences are developed in a partnership with other school subjects. Interdisciplinary projects are always valued from beginning to end of a project. It is common for teachers of different areas to work together in a Science project. Research of English written articles is very important not only for the development of our students' scientific literacy but also as a way of widening knowledge and a view on different perspectives of life instead of being limited to research of any articles in Portuguese language. In this study we are going to collect data about the predominant tree species in the region, especially the invasive trees from the acacia species, the native tree species and the commercial species. We are going to study the reasons for the appearance of each species and draw a chart of soil occupation in the council. This chart will also allow the study of the distribution and use of land for each tree species. This research work is the first stage for a contribution to warn the town council of the dangers of the invasive species to the future economy of the council.

  3. Plasma rest frame distributions of suprathermal ions in the earth's foreshock region

    International Nuclear Information System (INIS)

    Sentman, D.D.; Kennel, C.F.; Frank, L.A.

    1981-01-01

    We present rest frame ion distributions computed from three-dimensional observations of upstream superthermal ions gained by the Universtiy of Iowa Quadrispherical Lepedea on ISEE-1. The observations are for a single inbound, midmorning pass starting upstream from the ion foreshock and continuing across the quasiparallel bow shock into the magnetosheath. The crossing of the ion foreshock boundary is marked by a several minute burst of ions of temperature 100--200 eV moving along the IMF away from the bow shock at 500 km/s relative to the solar wind. The observation of these 'reflected' ions is followed by an extended interval of 'diffuse' ions of temperatures 2--3 keV flowing at approx.250 km/s relative to the solar wind and persisting until the bow shock is crossed. The diffuse ion β has a value of approximately 6 in the region of the superthermal ions, exceeding the normal thermal β of the solar wind by roughly an order of magnitude. Both types of superthermal ions constitute roughly 2% of the total ion density and carry a parallel heat flux of approx.2 x 10 -2 ergs cm -2 s -2 . When integrated over an assumed 10 x 10 R/sub E/ bow shock emission area, this implies an upstream dissipation that may approach 10 17 to 10 18 ergs/s, comparable to a modest substorm

  4. Plasma generator

    International Nuclear Information System (INIS)

    Omichi, Takeo; Yamanaka, Toshiyuki.

    1976-01-01

    Object: To recycle a coolant in a sealed hollow portion formed interiorly of a plasma limiter itself to thereby to cause direct contact between the coolant and the plasma limiter and increase of contact area therebetween to cool the plasma limiter. Structure: The heat resulting from plasma generated during operation and applied to the body of the plasma limiter is transmitted to the coolant, which recycles through an inlet and outlet pipe, an inlet and outlet nozzle and a hollow portion to hold the plasma limiter at a level less than a predetermined temperature. On the other hand, the heater wire is, at the time of emergency operation, energized to heat the plasma limiter, but this heat is transmitted to the limiter body to increase the temperature thereof. However, the coolant recycling the hollow portion comes into direct contact with the limiter body, and since the plasma limiter surround the hollow portion, the heat amount transmitted from the limiter body to the coolant increases to sufficiently cool the plasma limiter. (Yoshihara, H.)

  5. Investigations of the cathode region of an argon arc plasma by degenerate four-wave mixing laser spectroscopy and optical emission spectroscopy

    International Nuclear Information System (INIS)

    Dzierzega, K; Pokrzywka, B; Pellerin, S

    2004-01-01

    Degenerate four-wave mixing (DFWM) laser spectroscopy was used in local studies of atmospheric pressure argon plasma generated in a free-burning arc. The results of plasma diagnostics using the DFWM method were compared to the results obtained with optical emission measurements. In the cathode region of the arc the maxima of both the DFWM signal and the emission coefficient for the 696.5 nm Ar I line depend on the distance from the cathode tip. This effect proves the departure of the plasma state from local thermal equilibrium (LTE) as it has been reported by many authors. On the other hand the Stark shifts of the 696.5 nm Ar I line determined by the DFWM method in relation to plasma diagnostic results show no deviations from LTE on the arc axis down to 1.0 mm from the cathode tip

  6. Enhanced sources of acoustic power surrounding AR 11429

    International Nuclear Information System (INIS)

    Donea, Alina; Hanson, Christopher

    2013-01-01

    Multi-frequency power maps of the local acoustic oscillations show acoustic enhancements (''acoustic-power halos'') at high frequencies surrounding large active region. Computational seismic holography reveals a high-frequency ''acoustic-emission halo'', or ''seismic glory'' surrounding large active regions. In this study, we have applied computational seismic holography to map the seismic seismic source density surrounding AR 11429. Studies of HMI/SDO Doppler data, shows that the ''acoustic halos'' and the ''seismic glories'' are prominent at high frequencies 5–8 mHz. We investigate morphological properties of acoustic-power and acoustic emission halos around an active region to see if they are spatially correlated. Details about the local magnetic field from vectormagnetograms of AR 11429 are included. We identify a 15'' region of seismic deficit power (dark moat) shielding the white-light boundary of the active region. The size of the seismic moat is related to region of intermediate magnetic field strength. The acoustic moat is circled by the halo of enhanced seismic amplitude as well as enhanced seismic emission. Overall, the results suggest that features are related. However, if we narrow the frequency band to 5.5 – 6.5 mHz, we find that the seismic source density dominates over the local acoustic power, suggesting the existence of sources that emit more energy downward into the solar interior than upward toward the solar surface.

  7. EDITORIAL: Plasma jets and plasma bullets Plasma jets and plasma bullets

    Science.gov (United States)

    Kong, M. G.; Ganguly, B. N.; Hicks, R. F.

    2012-06-01

    Plasma plumes, or plasma jets, belong to a large family of gas discharges whereby the discharge plasma is extended beyond the plasma generation region into the surrounding ambience, either by a field (e.g. electromagnetic, convective gas flow, or shock wave) or a gradient of a directionless physical quantity (e.g. particle density, pressure, or temperature). This physical extension of a plasma plume gives rise to a strong interaction with its surrounding environment, and the interaction alters the properties of both the plasma and the environment, often in a nonlinear and dynamic fashion. The plasma is therefore not confined by defined physical walls, thus extending opportunities for material treatment applications as well as bringing in new challenges in science and technology associated with complex open-boundary problems. Some of the most common examples may be found in dense plasmas with very high dissipation of externally supplied energy (e.g. in electrical, optical or thermal forms) and often in or close to thermal equilibrium. For these dense plasmas, their characteristics are determined predominantly by strong physical forces of different fields, such as electrical, magnetic, thermal, shock wave, and their nonlinear interactions [1]. Common to these dense plasma plumes are significant macroscopic plasma movement and considerable decomposition of solid materials (e.g. vaporization). Their applications are numerous and include detection of elemental traces, synthesis of high-temperature materials and welding, laser--plasma interactions, and relativistic jets in particle accelerators and in space [2]-[4]. Scientific challenges in the understanding of plasma jets are exciting and multidisciplinary, involving interweaving transitions of all four states of matter, and their technological applications are wide-ranging and growing rapidly. Using the Web of Science database, a search for journal papers on non-fusion plasma jets reveals that a long initial phase up

  8. Lateral mobility of plasma membrane lipids in Xenopus eggs: regional differences related to animal/vegetal polarity become extreme upon fertilization.

    Science.gov (United States)

    Dictus, W J; van Zoelen, E J; Tetteroo, P A; Tertoolen, L G; de Laat, S W; Bluemink, J G

    1984-01-01

    Regional differences in the lateral mobility properties of plasma membrane lipids have been studied in unfertilized and fertilized Xenopus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein-labeled fatty acids HEDAF (5-(N-hexadecanoyl)-aminofluorescein) and TEDAF (5-(N-tetradecanoyl)-aminofluorescein) appear to partition into the plasma membrane. Under all experimental conditions used these molecules show partial recovery upon photobleaching indicating the existence of lipidic microdomains. In the unfertilized egg the mobile fraction of plasma membrane lipids (approximately 50%) has a fivefold smaller lateral diffusion coefficient (D = 1.5 X 10(-8) cm2/sec) in the animal than in the vegetal plasma membrane (D = 7.6 X 10(-8) cm2/sec). This demonstrates the presence of an animal/vegetal polarity within the Xenopus egg plasma membrane. Upon fertilization this polarity is strongly (greater than 100X) enhanced leading to the formation of two distinct macrodomains within the plasma membrane. At the animal side of the egg lipids are completely immobilized on the time scale of FPR measurements (D less than 10(-10) cm2/sec), whereas at the vegetal side D is only slightly reduced (D = 4.4 X 10(-8) cm2/sec). The immobilization of animal plasma membrane lipids, which could play a role in the polyspermy block, probably arises by the fusion of cortical granules which are more numerous here. The transition between the animal and the vegetal domain is sharp and coincides with the boundary between the presumptive ecto- and endoderm. The role of regional differences in the plasma membrane is discussed in relation to cell diversification in early development.

  9. Opportunity's Surroundings on Sol 1798 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11850 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11850 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo 180-degree view of the rover's surroundings during the 1,798th Martian day, or sol, of Opportunity's surface mission (Feb. 13, 2009). North is on top. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 111 meters (364 feet) southward on the preceding sol. Tracks from that drive recede northward in this view. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  10. Opportunity's Surroundings on Sol 1818 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11846 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11846 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,818th Martian day, or sol, of Opportunity's surface mission (March 5, 2009). South is at the center; north at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 80.3 meters (263 feet) southward earlier on that sol. Tracks from the drive recede northward in this view. The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  11. Opportunity's Surroundings After Sol 1820 Drive (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11841 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11841 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  12. The lithosphere-asthenosphere: Italy and surroundings

    International Nuclear Information System (INIS)

    Panza, G.F.; Aoudia, A.; Pontevivo, A.; Chimera, G.; Raykova, R.

    2003-02-01

    The velocity-depth distribution of the lithosphere-asthenosphere in the Italian region and surroundings is imaged, with a lateral resolution of about 100 km, by surface wave velocity tomography and non-linear inversion. Maps of the Moho depth, of the thickness of the lithosphere and of the shear-wave velocities, down to depths of 200 km and more, are constructed. A mantle wedge, identified in the uppermost mantle along the Apennines and the Calabrian Arc, underlies the principal recent volcanoes, and partial melting can be relevant in this part of the uppermost mantle. In Calabria a lithospheric doubling is seen, in connection with the subduction of the Ionian lithosphere. The asthenosphere is shallow in the Southern Tyrrhenian Sea. High velocity bodies, cutting the asthenosphere, outline the Adria-lonian subduction in the Tyrrhenian Sea and the deep-reaching lithospheric root in the Western Alps. Less deep lithospheric roots are seen in the Central Apennines. The lithosphere-asthenosphere properties delineate a differentiation between the northern and the southern sectors of the Adriatic Sea, likely attesting the fragmentation of Adria. (author)

  13. The lithosphere-asthenosphere Italy and surroundings

    CERN Document Server

    Panza, G F; Chimera, G; Pontevivo, A; Raykova, R

    2003-01-01

    The velocity-depth distribution of the lithosphere-asthenosphere in the Italian region and surroundings is imaged, with a lateral resolution of about 100 km, by surface wave velocity tomography and non-linear inversion. Maps of the Moho depth, of the thickness of the lithosphere and of the shear-wave velocities, down to depths of 200 km and more, are constructed. A mantle wedge, identified in the uppermost mantle along the Apennines and the Calabrian Arc, underlies the principal recent volcanoes, and partial melting can be relevant in this part of the uppermost mantle. In Calabria a lithospheric doubling is seen, in connection with the subduction of the Ionian lithosphere. The asthenosphere is shallow in the Southern Tyrrhenian Sea. High velocity bodies, cutting the asthenosphere, outline the Adria-lonian subduction in the Tyrrhenian Sea and the deep-reaching lithospheric root in the Western Alps. Less deep lithospheric roots are seen in the Central Apennines. The lithosphere-asthenosphere properties delineat...

  14. Ultrastructural relationship of the phagophore with surrounding organelles.

    Science.gov (United States)

    Biazik, Joanna; Ylä-Anttila, Päivi; Vihinen, Helena; Jokitalo, Eija; Eskelinen, Eeva-Liisa

    2015-01-01

    Phagophore nucleates from a subdomain of the endoplasmic reticulum (ER) termed the omegasome and also makes contact with other organelles such as mitochondria, Golgi complex, plasma membrane and recycling endosomes during its formation. We have used serial block face scanning electron microscopy (SB-EM) and electron tomography (ET) to image phagophore biogenesis in 3 dimensions and to determine the relationship between the phagophore and surrounding organelles at high resolution. ET was performed to confirm whether membrane contact sites (MCSs) are evident between the phagophore and those surrounding organelles. In addition to the known contacts with the ER, we identified MCSs between the phagophore and membranes from putative ER exit sites, late endosomes or lysosomes, the Golgi complex and mitochondria. We also show that one phagophore can have simultaneous MCSs with more than one organelle. Future membrane flux experiments are needed to determine whether membrane contacts also signify lipid translocation.

  15. Lateral mobility of plasma membrane lipids in Xenopus eggs: Regional differences related to animal/vegetal polarity become extreme upon fertilization

    NARCIS (Netherlands)

    Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van; Tetteroo, P.A.T.; Tertoolen, L.G.J.; Laat, S.W. de

    1984-01-01

    Regional differences in the lateral mobility properties of plasma membrane lipids have been studied in unfertilized and fertilizedxaqpus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein-labeled fatty acids

  16. Identification of polymorphisms in the 5'-untranslated region of the TAFI gene: relationship with plasma TAFI levels and risk of venous thrombosis

    NARCIS (Netherlands)

    Franco, R. F.; Fagundes, M. G.; Meijers, J. C.; Reitsma, P. H.; Lourenço, D.; Morelli, V.; Maffei, F. H.; Ferrari, I. C.; Piccinato, C. E.; Silva, W. A.; Zago, M. A.

    2001-01-01

    BACKGROUND AND OBJECTIVES: Thrombin activatable fibrinolysis inhibitor (TAFI) plays an important role in hemostasis, functioning as a potent fibrinolysis inhibitor. TAFI gene variations may contribute to plasma TAFI levels and thrombotic risk. DESIGN AND METHODS: We sequenced a 2083-bp region of the

  17. Beam-generated plasmas for processing applications

    Science.gov (United States)

    Meger, R. A.; Blackwell, D. D.; Fernsler, R. F.; Lampe, M.; Leonhardt, D.; Manheimer, W. M.; Murphy, D. P.; Walton, S. G.

    2001-05-01

    The use of moderate energy electron beams (e-beams) to generate plasma can provide greater control and larger area than existing techniques for processing applications. Kilovolt energy electrons have the ability to efficiently ionize low pressure neutral gas nearly independent of composition. This results in a low-temperature, high-density plasma of nearly controllable composition generated in the beam channel. By confining the electron beam magnetically the plasma generation region can be designated independent of surrounding structures. Particle fluxes to surfaces can then be controlled by the beam and gas parameters, system geometry, and the externally applied rf bias. The Large Area Plasma Processing System (LAPPS) utilizes a 1-5 kV, 2-10 mA/cm2 sheet beam of electrons to generate a 1011-1012cm-3 density, 1 eV electron temperature plasma. Plasma sheets of up to 60×60 cm2 area have been generated in a variety of molecular and atomic gases using both pulsed and cw e-beam sources. The theoretical basis for the plasma production and decay is presented along with experiments measuring the plasma density, temperature, and potential. Particle fluxes to nearby surfaces are measured along with the effects of radio frequency biasing. The LAPPS source is found to generate large-area plasmas suitable for materials processing.

  18. Hurricane Sandy: Rapid Response Imagery of the Surrounding Regions

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of Hurricane Sandy. The aerial photography missions were conducted by the NOAA Remote Sensing Division. The images were acquired...

  19. Plasma confinement in a magnetic field of the internal ring current

    International Nuclear Information System (INIS)

    Shafranov, Vitaly; Popovich, Paul; Samitov, Marat

    2000-01-01

    Plasma confinement in compact region surrounding an internal ring current is considered. As the limiting case of large aspect ratio system the cylindrical plasma is considered initially. Analysis of the cylindrical tubular plasma equilibrium and stability against the most dangerous flute (m=0) and kink (m=1) modes revealed the possibility of the MHD stable plasma confined by magnetic field of the internal rod current, with rather peaked plasma pressure and maximal local beta β(γ)=0.4. In case of the toroidal internal ring system an additional external magnetic field creates the boundary separatrix witch limits the plasma volume. The dependence of the plasma pressure profiles, marginally stable with respect to the flute modes, from the shape of the external plasma boundary (separatrix) in such kind closed toroidal systems is investigated. The internal ring system with circular poloidal magnetic mirror, where the ring supports could be placed, is proposed. (author)

  20. Tissue-specific bioaccumulation of human and veterinary antibiotics in bile, plasma, liver and muscle tissues of wild fish from a highly urbanized region

    International Nuclear Information System (INIS)

    Zhao, Jian-Liang; Liu, You-Sheng; Liu, Wang-Rong; Jiang, Yu-Xia; Su, Hao-Chang; Zhang, Qian-Qian; Chen, Xiao-Wen; Yang, Yuan-Yuan; Chen, Jun; Liu, Shuang-Shuang; Pan, Chang-Gui; Huang, Guo-Yong; Ying, Guang-Guo

    2015-01-01

    We investigated the bioaccumulation of antibiotics in bile, plasma, liver and muscle tissues of wild fish from four rivers in the Pearl River Delta region. In total, 12 antibiotics were present in at least one type of fish tissues from nine wild fish species in the four rivers. The mean values of log bioaccumulation factors (log BAFs) for the detected antibiotics in fish bile, plasma, liver, and muscle tissues were at the range of 2.06–4.08, 1.85–3.47, 1.41–3.51, and 0.48–2.70, respectively. As the digestion tissues, fish bile, plasma, and liver showed strong bioaccumulation ability for some antibiotics, indicating a different bioaccumulation pattern from hydrophobic organic contaminants. Human health risk assessment based on potential fish consumption indicates that these antibiotics do not appear to pose an appreciable risk to human health. To the best of our knowledge, this is first report of bioaccumulation patterns of antibiotics in wild fish bile and plasma. - Highlights: • We investigated the bioaccumulation of antibiotics in wild fish from the Pearl River Delta region. • Twelve antibiotics were found in fish bile, plasma, liver and muscle tissues. • High log bioaccumulation factors suggested strong bioaccumulation ability for some antibiotics in wild fish tissues. • The presence of antibiotics in fish bile and plasma tissues indicates a novel bioaccumulation pattern. • Potential adverse effects are possibly caused by the high internal antibiotic concentrations in tissues. - Fish bile and plasma displayed strong bioaccumulation ability for some antibiotics, indicating a novel bioaccumulation pattern for antibiotics in the contaminated environment

  1. Lateral mobility of plasma membrane proteins in dividing eggs of the loach (Misgurnus fossilis): Regional differences and changes during the cell cycle.

    Science.gov (United States)

    Bozhkova, V P; Budayova, M; Kvasnicka, P; Cigankova, N; Chorvat, D

    1994-12-01

    Regional differences in lateral diffusion rates of fluorescence-labeled proteins have been studied in the plasma membrane of dividing eggs of the loach (Misgurnus fossilis) by fluorescence recovery after photobleaching (FRAP). Apparent animal-vegetal differences in fluorescence intensity, lateral diffusion coefficients, and fractions of mobile proteins have been found, with all these quantities being higher in the animal pole region than in the yolk region. Cyclic changes in protein diffusion coefficients and mobile fractions during the first few cell cycles have also been recorded. Soon after the end of a cleavage, the diffusion coefficient reaches its minimal value and increases rapidly before the next cleavage.

  2. Religion's relationship with social boundaries surrounding gender ...

    African Journals Online (AJOL)

    Religion's relationship with social boundaries surrounding gender. ... is associated with segregation, marginalization and differentiation between men and women. ... are necessary in the society it should not be mistaken for gender inequality.

  3. Hypersonic drift-tearing magnetic islands in tokamak plasmas

    International Nuclear Information System (INIS)

    Fitzpatrick, R.; Waelbroeck, F. L.

    2007-01-01

    A two-fluid theory of long wavelength, hypersonic, drift-tearing magnetic islands in low-collisionality, low-β plasmas possessing relatively weak magnetic shear is developed. The model assumes both slab geometry and cold ions, and neglects electron temperature and equilibrium current gradient effects. The problem is solved in three asymptotically matched regions. The 'inner region' contains the island. However, the island emits electrostatic drift-acoustic waves that propagate into the surrounding 'intermediate region', where they are absorbed by the plasma. Since the waves carry momentum, the inner region exerts a net force on the intermediate region, and vice versa, giving rise to strong velocity shear in the region immediately surrounding the island. The intermediate region is matched to the surrounding 'outer region', in which ideal magnetohydrodynamic holds. Isolated hypersonic islands propagate with a velocity that lies between those of the unperturbed local ion and electron fluids, but is much closer to the latter. The ion polarization current is stabilizing, and increases with increasing island width. Finally, the hypersonic branch of isolated island solutions ceases to exist above a certain critical island width. Hypersonic islands whose widths exceed the critical width are hypothesized to bifurcate to the so-called 'sonic' solution branch

  4. Plasma Heating and Alfvénic Turbulence Enhancement During Two Steps of Energy Conversion in Magnetic Reconnection Exhaust Region of Solar Wind

    Science.gov (United States)

    Jiansen, He; Xingyu, Zhu; Yajie, Chen; Chadi, Salem; Michael, Stevens; Hui, Li; Wenzhi, Ruan; Lei, Zhang; Chuanyi, Tu

    2018-04-01

    The magnetic reconnection exhaust is a pivotal region with enormous magnetic energy being continuously released and converted. The physical processes of energy conversion involved are so complicated that an all-round understanding based on in situ measurements is still lacking. We present the evidence of plasma heating by illustrating the broadening of proton and electron velocity distributions, which are extended mainly along the magnetic field, in an exhaust of interchange reconnection between two interplanetary magnetic flux tubes of the same polarity on the Sun. The exhaust is asymmetric across an interface, with both sides being bounded by a pair of compound discontinuities consisting of rotational discontinuity and slow shock. The energized plasmas are found to be firehose unstable, and responsible for the emanation of Alfvén waves during the second step of energy conversion. It is realized that the energy conversion in the exhaust can be a two-step process involving both plasma energization and wave emission.

  5. Trajectories and Maneuvers of Surrounding Vehicles with Panoramic Camera Arrays

    DEFF Research Database (Denmark)

    Dueholm, Jacob Velling; Kristoffersen, Miklas Strøm; Satzoda, Ravi K.

    2016-01-01

    Vision-based research for intelligent vehicles have traditionally focused on specific regions around a vehicle, such as a front looking camera for, e.g., lane estimation. Traffic scenes are complex and vital information could be lost in unobserved regions. This paper proposes a framework that uses...... four visual sensors for a full surround view of a vehicle in order to achieve an understanding of surrounding vehicle behaviors. The framework will assist the analysis of naturalistic driving studies by automating the task of data reduction of the observed trajectories. To this end, trajectories...... are estimated using a vehicle detector together with a multiperspective optimized tracker in each view. The trajectories are transformed to a common ground plane, where they are associated between perspectives and analyzed to reveal tendencies around the ego-vehicle. The system is tested on sequences from 2.5 h...

  6. The relationship in Japanese infants between a genetic polymorphism in the promoter region of the insulin-like growth factor I gene and the plasma level.

    Science.gov (United States)

    Kinoshita, Yumiko; Kizaki, Zenro; Ishihara, Yasunori; Nakajima, Hisakazu; Adachi, Shinsuke; Kosaka, Kitaro; Kinugasa, Akihiko; Sugimoto, Tohru

    2007-01-01

    Evidence is accumulating that the promoter region of the insulin-like growth factor I (IGF-I) gene polymorphism and low levels of IGF-I are associated with type 2 diabetes, cardiovascular disease and birth weight; however, the number of wild-type alleles is different in each country. This study aimed to examine the 737/738 marker, a cytosine-adenine repeat in the promoter region of the IGF-I gene polymorphism, and plasma IGF-I levels in Japanese infants and analyze the genetic background. Data were collected for 15 months in Kyoto Prefectural University of Medicine. The body composition parameters of all infants were determined at birth. At 5 days after birth, we took blood samples to measure the product size of the promoter region of the IGF-I gene polymorphism and plasma IGF-I. In a population-based sample of 160 subjects, 6 different alleles and 16 genotypes were identified in the promoter region of the IGF-I gene polymorphism. The existence of a 196-bp allele has proved to result in a low plasma IGF-I level, a small head and chest circumference (p body composition parameters in Japanese infants. Our results suggest genetical influence on prenatal growth and serum IGF-I levels.

  7. Simulation study of wave phenomena from the sheath region in single frequency capacitively coupled plasma discharges; field reversals and ion reflection

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, S.; Turner, M. M. [National Centre for Plasma Science and Technology, School of Physical Sciences, Dublin City University, Dublin 9 (Ireland)

    2013-07-15

    Capacitively coupled radio-frequency (RF) discharges have great significance for industrial applications. Collisionless electron heating in such discharges is important, and sometimes is the dominant mechanism. This heating is usually understood to originate in a stochastic interaction between electrons and the electric fields. However, other mechanisms may also be important. There is evidence of wave emission with a frequency near the electron plasma frequency, i.e., ω{sub pe}, from the sheath region in collisionless capacitive RF discharges. This is the result of a progressive breakdown of quasi-neutrality close to the electron sheath edge. These waves are damped in a few centimeters during their propagation from the sheath towards the bulk plasma. The damping occurs because of the Landau damping or some related mechanism. This research work reports that the emission of waves is associated with a field reversal during the expanding phase of the sheath. Trapping of electrons near to this field reversal region is observed. The amplitude of the wave increases with increasing RF current density amplitude J(tilde sign){sub 0} until some maximum is reached, beyond which the wave diminishes and a new regime appears. In this new regime, the density of the bulk plasma suddenly increases because of ion reflection, which occurs due to the presence of strong field reversal near sheath region. Our calculation shows that these waves are electron plasma waves. These phenomena occur under extreme conditions (i.e., higher J(tilde sign){sub 0} than in typical experiments) for sinusoidal current waveforms, but similar effects may occur with non-sinusoidal pulsed waveforms for conditions of experimental interest, because the rate of change of current is a relevant parameter. The effect of electron elastic collisions on plasma waves is also investigated.

  8. Ecological mechanisms linking protected areas to surrounding lands.

    Science.gov (United States)

    Hansen, Andrew J; DeFries, Ruth

    2007-06-01

    Land use is expanding and intensifying in the unprotected lands surrounding many of the world's protected areas. The influence of this land use change on ecological processes is poorly understood. The goal of this paper is to draw on ecological theory to provide a synthetic framework for understanding how land use change around protected areas may alter ecological processes and biodiversity within protected areas and to provide a basis for identifying scientifically based management alternatives. We first present a conceptual model of protected areas embedded within larger ecosystems that often include surrounding human land use. Drawing on case studies in this Invited Feature, we then explore a comprehensive set of ecological mechanisms by which land use on surrounding lands may influence ecological processes and biodiversity within reserves. These mechanisms involve changes in ecosystem size, with implications for minimum dynamic area, species-area effect, and trophic structure; altered flows of materials and disturbances into and out of reserves; effects on crucial habitats for seasonal and migration movements and population source/sink dynamics; and exposure to humans through hunting, poaching, exotics species, and disease. These ecological mechanisms provide a basis for assessing the vulnerability of protected areas to land use. They also suggest criteria for designing regional management to sustain protected areas in the context of surrounding human land use. These design criteria include maximizing the area of functional habitats, identifying and maintaining ecological process zones, maintaining key migration and source habitats, and managing human proximity and edge effects.

  9. Enhancement of Afterimage Colors by Surrounding Contours

    Directory of Open Access Journals (Sweden)

    Takao Sato

    2011-05-01

    Full Text Available Presenting luminance contours surrounding the adapted areas in test phase enhances color afterimages in both duration and color appearance. The presence of surrounding contour is crucial to some color phenomenon such as van Lier's afterimage, but the contour-effect itself has not been seriously examined. In this paper, we compared the contour-effect to color afterimages and to actually colored patches to examine the nature of color information subserving color-aftereffect. In the experiment, observers were adapted for 1 sec to a small colored square (red, green, yellow, or blue presented on a gray background. Then, a test field either with or without surrounding contour was presented. Observers matched the color of a test-patch located near the afterimage to the color of afterimage. It was found that the saturation of negative afterimage was almost doubled by the presence of surrounding contours. There was no effect of luminance contrast or polarity of contours. In contrast, no enhancement of saturation by surrounding contours was observed for actually colored patches even though the colors of patches were equalized to that of afterimage without contours. This dissociation in the contour-effect demonstrates the crucial difference between the color information for aftereffects and for ordinary bottom-up color perception.

  10. Light element atom, molecule and radical behaviour in the divertor and edge plasma regions. Summary report of the 1. research coordination meeting

    International Nuclear Information System (INIS)

    Braams, B.J.

    2010-01-01

    The first research coordination meeting of the Coordinated Research Project (CRP) on Light Element Atom, Molecule and Radical Behaviour in the Divertor and Edge Plasma Regions was held 18-20 November 2009 at IAEA headquarters, bringing together experts representing 14 institutions. Participants summarized their recent and ongoing work pertinent to the research project. The specific objectives of the CRP and a detailed work plan were formulated. The discussions, conclusions and recommendations of the meeting are summarized in this report. (author)

  11. X-Ray Flare Oscillations Track Plasma Sloshing along Star-disk Magnetic Tubes in the Orion Star-forming Region

    Science.gov (United States)

    Reale, Fabio; Lopez-Santiago, Javier; Flaccomio, Ettore; Petralia, Antonino; Sciortino, Salvatore

    2018-03-01

    Pulsing X-ray emission tracks the plasma “echo” traveling in an extremely long magnetic tube that flares in an Orion pre-main sequence (PMS) star. On the Sun, flares last from minutes to a few hours and the longest-lasting ones typically involve arcades of closed magnetic tubes. Long-lasting X-ray flares are observed in PMS stars. Large-amplitude (∼20%), long-period (∼3 hr) pulsations are detected in the light curve of day-long flares observed by the Advanced CCD Imaging Spectrometer on-board Chandra from PMS stars in the Orion cluster. Detailed hydrodynamic modeling of two flares observed on V772 Ori and OW Ori shows that these pulsations may track the sloshing of plasma along a single long magnetic tube, triggered by a sufficiently short (∼1 hr) heat pulse. These magnetic tubes are ≥20 solar radii long, enough to connect the star with the surrounding disk.

  12. Nonequilibrium phenomena and determination of plasma parameters in the hot core of the cathode region in free-burning arc discharges

    International Nuclear Information System (INIS)

    Kuehn, Gerrit; Kock, Manfred

    2007-01-01

    We present spectroscopic measurements of plasma parameters (electron density n e , electron temperature T e , gas temperature T g , underpopulation factor b) in the hot-core region in front of the cathode of a low-current, free-burning arc discharge in argon under atmospheric pressure. The discharge is operated in the hot-core mode, creating a hot cathode region with plasma parameters similar to high-current arcs in spite of the fact that we use comparatively low currents (less than 20 A). We use continuum emission and (optically thin) line emission to determine n e and T e . We apply relaxation measurements based on a power-interruption technique to investigate deviations from local thermodynamic equilibrium (LTE). These measurements let us determine the gas temperature T g . All measurements are performed side-on with charge-coupled-device cameras as detectors, so that all measured plasma parameters are spatially resolved after an Abel inversion. This yields the first ever spatially resolved observation of the non-LTE phenomena of the hot core in the near-cathode region of free-burning arcs. The results only partly coincide with previously published predictions and measurements in the literature

  13. PIC Modeling of Argon Plasma Flow in MNX

    Science.gov (United States)

    Cohen, Samuel; Sefkow, Adam

    2007-11-01

    A linear helicon-heated plasma device - the Magnetic Nozzle Experiment (MNX) at the Princeton Plasma Physics Laboratory - is used for studies of the formation of strong electrostatic double layers near mechanical and magnetic apertures and the acceleration of plasma ions into supersonic directed beams. In order to characterize the role of the aperture and its involvement with ion acceleration, detailed particle-in-cell simulations are employed to study the effects of the surrounding boundary geometry on the plasma dynamics near the aperture region, within which the transition from a collisional to collisionless regime occurs. The presence of a small superthermal electron population is examined, and the model includes a background neutral population which can be ionized by energetic electrons. By self-consistently evaluating the temporal evolution of the plasma in the vicinity of the aperture, the formation mechanism of the double layer is investigated.

  14. Explaining preferences for home surroundings and locations

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    2011-01-01

    This article is based on a survey carried out in Denmark that asked a random sample of the population about their preferences for home surroundings and locations. It shows that the characteristics of social surroundings are very important and can be divided into three independent dimensions......: avoiding social nuisances, preferring social homogeneity and living close to one’s social network and place of origin. The study shows that most people have many detailed preferences, whereas some have very few. This confirms an earlier theory that some people are very connected to certain places...... with given characteristics and thus do not have priorities regarding home surroundings and locations. For others, mostly young people and singles, home is just a place to sleep and relax, whereas life is lived elsewhere. For this group, there are only preferences for location and there are few specific...

  15. Smart Chips for Smart Surroundings -- 4S

    NARCIS (Netherlands)

    Schuler, Eberhard; König, Ralf; Becker, Jürgen; Rauwerda, G.K.; van de Burgwal, M.D.; Smit, Gerardus Johannes Maria; Cardoso, João M.P.; Hübner, Michael

    2011-01-01

    The overall mission of the 4S project (Smart Chips for Smart Surroundings) was to define and develop efficient flexible, reconfigurable core building blocks, including the supporting tools, for future Ambient System Devices. Reconfigurability offers the needed flexibility and adaptability, it

  16. Childhood Suicide and Myths Surrounding It.

    Science.gov (United States)

    Greene, Dorothea B.

    1994-01-01

    Dispels five misconceptions surrounding the suicide of children: that children under the age of six do not commit suicide; that suicide in latency years is extremely rare; that psychodynamically and developmentally true depression is not possible in childhood; that child cannot understand finality of death; and that children are cognitively and…

  17. Effect of cooler electrons on a compressive ion acoustic solitary wave in a warm ion plasma — Forbidden regions, double layers, and supersolitons

    International Nuclear Information System (INIS)

    Ghosh, S. S.; Sekar Iyengar, A. N.

    2014-01-01

    It is observed that the presence of a minority component of cooler electrons in a three component plasma plays a deterministic role in the evolution of solitary waves, double layers, or the newly discovered structures called supersolitons. The inclusion of the cooler component of electrons in a single electron plasma produces sharp increase in nonlinearity in spite of a decrease in the overall energy of the system. The effect maximizes at certain critical value of the number density of the cooler component (typically 15%–20%) giving rise to a hump in the amplitude variation profile. For larger amplitudes, the hump leads to a forbidden region in the ambient cooler electron concentration which dissociates the overall existence domain of solitary wave solutions in two distinct parameter regime. It is observed that an inclusion of the cooler component of electrons as low as < 1% affects the plasma system significantly resulting in compressive double layers. The solution is further affected by the cold to hot electron temperature ratio. In an adequately hotter bulk plasma (i.e., moderately low cold to hot electron temperature ratio), the parameter domain of compressive double layers is bounded by a sharp discontinuity in the corresponding amplitude variation profile which may lead to supersolitons

  18. Effect of cooler electrons on a compressive ion acoustic solitary wave in a warm ion plasma — Forbidden regions, double layers, and supersolitons

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S. S., E-mail: sukti@iigs.iigm.res.in [Indian Institute of Geomagnetism, New Panvel, Navi Mumbai 410218 (India); Sekar Iyengar, A. N. [Plasma Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India)

    2014-08-15

    It is observed that the presence of a minority component of cooler electrons in a three component plasma plays a deterministic role in the evolution of solitary waves, double layers, or the newly discovered structures called supersolitons. The inclusion of the cooler component of electrons in a single electron plasma produces sharp increase in nonlinearity in spite of a decrease in the overall energy of the system. The effect maximizes at certain critical value of the number density of the cooler component (typically 15%–20%) giving rise to a hump in the amplitude variation profile. For larger amplitudes, the hump leads to a forbidden region in the ambient cooler electron concentration which dissociates the overall existence domain of solitary wave solutions in two distinct parameter regime. It is observed that an inclusion of the cooler component of electrons as low as < 1% affects the plasma system significantly resulting in compressive double layers. The solution is further affected by the cold to hot electron temperature ratio. In an adequately hotter bulk plasma (i.e., moderately low cold to hot electron temperature ratio), the parameter domain of compressive double layers is bounded by a sharp discontinuity in the corresponding amplitude variation profile which may lead to supersolitons.

  19. Plasma universe

    International Nuclear Information System (INIS)

    Alfven, H.

    1986-04-01

    Traditionally the views in our cosmic environment have been based on observations in the visual octave of the electromagnetic spectrum, during the last half-century supplemented by infrared and radio observations. Space research has opened the full spectrum. Of special importance are the X-ray-gamma-ray regions, in which a number of unexpected phenomena have been discovered. Radiations in these regions are likely to originate mainly from magnetised cosmic plasma. Such a medium may also emit synchrotron radiation which is observable in the radio region. If we try to base a model of the universe on the plasma phenomena mentioned we find that the plasma universe is drastically different from the traditional visual universe. Information about the plasma universe can also be obtained by extrapolation of laboratory experiments and magnetospheric in situ measurements of plasma. This approach is possible because it is likely that the basic properties of plasma are the same everywhere. In order to test the usefulness of the plasma universe model we apply it to cosmogony. Such an approach seems to be rather successful. For example, the complicated structure of the Saturnian C ring can be accounted for. It is possible to reconstruct certain phenomena 4-5 bilions years ago with an accuracy of better than 1 percent

  20. Identification of β-SiC surrounded by relatable surrounding diamond ...

    Indian Academy of Sciences (India)

    β-SiC is identified in the presence of a relatable surrounding diamond medium using subtle, but discernible Raman ... Change in the nature of the surrounding material structure and its .... intensity implies very low graphite content in thin film. In.

  1. INTERACTIONS OF THE INFRARED BUBBLE N4 WITH ITS SURROUNDINGS

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hong-Li; Li, Jin-Zeng; Yuan, Jing-Hua; Huang, Maohai; Huang, Ya-Fang; Zhang, Si-Ju [National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012 (China); Wu, Yuefang [Department of Astronomy, Peking University, 100871 Beijing (China); Liu, Tie [Korea Astronomy and Space Science Institute 776, Daedeokdae-ro, Yuseong-gu, Daejeon, 305-348 (Korea, Republic of); Dubner, G.; Paron, S.; Ortega, M. E. [1Instituto de Astronomía y Física del Espacio (IAFE, CONICET-UBA), CC 67, Suc. 28, 1428 Buenos Aires (Argentina); Molinari, Sergio [Istituto di Astrofisica e Planetologia Spaziali—IAPS, Istituto Nazionale di Astrofisica—INAF, via Fosso del Cavaliere 100, I-00133 Roma (Italy); Zavagno, Annie; Samal, Manash R., E-mail: hlliu@nao.cas.cn [Aix Marseille Universit, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, F-13388, Marseille (France)

    2016-02-10

    The physical mechanisms that induce the transformation of a certain mass of gas in new stars are far from being well understood. Infrared bubbles associated with H ii regions have been considered to be good samples for investigating triggered star formation. In this paper we report on the investigation of the dust properties of the infrared bubble N4 around the H ii region G11.898+0.747, analyzing its interaction with its surroundings and star formation histories therein, with the aim of determining the possibility of star formation triggered by the expansion of the bubble. Using Herschel PACS and SPIRE images with a wide wavelength coverage, we reveal the dust properties over the entire bubble. Meanwhile, we are able to identify six dust clumps surrounding the bubble, with a mean size of 0.50 pc, temperature of about 22 K, mean column density of 1.7 × 10{sup 22} cm{sup −2}, mean volume density of about 4.4 × 10{sup 4} cm{sup −3}, and a mean mass of 320 M{sub ⊙}. In addition, from PAH emission seen at 8 μm, free–free emission detected at 20 cm, and a probability density function in special regions, we could identify clear signatures of the influence of the H ii region on the surroundings. There are hints of star formation, though further investigation is required to demonstrate that N4 is the triggering source.

  2. Control of the magnetic topology and plasma exhaust in the edge region of Wendelstein 7-X. A numerical study

    Energy Technology Data Exchange (ETDEWEB)

    Hoelbe, Hauke

    2016-02-15

    Nuclear fusion is the energy source of the stars and has the potential of being the main energy source for mankind in the future. The research on fusion energy focuses primarily on magnetic confinement, where hot plasma - with temperatures on the order of 100 million degrees Celsius - are confined by specially designed toroidal magnetic topology. The main candidates for magnetic confinement are the tokamak and the stellarator. The tokamak concept is further developed than the stellarator concept, but the stellarator concept has some intrinsic and potentially very important advantages and is therefore also actively pursued. The Wendelstein 7-X (W7-X) stellarator will be the world's leading stellarator experiment. It is about to go into operation in Greifswald, Germany. This thesis delves into some very important scientific challenges for the stellarator concept as a whole and W7-X in particular, namely, how one effectively interfaces the hot plasma with the material walls of the experiment, in special how the plasma heat and particle fluxes are controlled. The fundamental concept that will be used in W7-X for particle and heat exhaust is the island divertor. Although the divertor concept at a stellarator was invented by Lyman Spitzer back in the 1950s, the stellarator island divertor still needs to be experimentally tested at fusion-relevant heat loads and temperatures in steady-state. W7-X is the first experiment that will be able to do so. A number of theoretical and numerical studies have been performed to guide the design of the divertor components. The actual divertor components are in series production at this time, and are largely compatible with the expected heat loads. However, with the sophisticated codes now available, it has become clear that there are some, otherwise very attractive, operational scenarios that could lead to overloading of the W7-X divertors. At least one mitigation strategy was proposed but was until now not analyzed in sufficient

  3. Control of the magnetic topology and plasma exhaust in the edge region of Wendelstein 7-X. A numerical study

    International Nuclear Information System (INIS)

    Hoelbe, Hauke

    2016-01-01

    Nuclear fusion is the energy source of the stars and has the potential of being the main energy source for mankind in the future. The research on fusion energy focuses primarily on magnetic confinement, where hot plasma - with temperatures on the order of 100 million degrees Celsius - are confined by specially designed toroidal magnetic topology. The main candidates for magnetic confinement are the tokamak and the stellarator. The tokamak concept is further developed than the stellarator concept, but the stellarator concept has some intrinsic and potentially very important advantages and is therefore also actively pursued. The Wendelstein 7-X (W7-X) stellarator will be the world's leading stellarator experiment. It is about to go into operation in Greifswald, Germany. This thesis delves into some very important scientific challenges for the stellarator concept as a whole and W7-X in particular, namely, how one effectively interfaces the hot plasma with the material walls of the experiment, in special how the plasma heat and particle fluxes are controlled. The fundamental concept that will be used in W7-X for particle and heat exhaust is the island divertor. Although the divertor concept at a stellarator was invented by Lyman Spitzer back in the 1950s, the stellarator island divertor still needs to be experimentally tested at fusion-relevant heat loads and temperatures in steady-state. W7-X is the first experiment that will be able to do so. A number of theoretical and numerical studies have been performed to guide the design of the divertor components. The actual divertor components are in series production at this time, and are largely compatible with the expected heat loads. However, with the sophisticated codes now available, it has become clear that there are some, otherwise very attractive, operational scenarios that could lead to overloading of the W7-X divertors. At least one mitigation strategy was proposed but was until now not analyzed in sufficient

  4. Cosmic plasma

    Energy Technology Data Exchange (ETDEWEB)

    Alfven, H [California Univ., San Diego, La Jolla (USA)

    1981-01-01

    The properties of space plasmas are analyzed, based on laboratory results and data obtained by in situ measurements in the magnetosphere (including the heliosphere). Attention is given to the question of how much knowledge can be gained by a systematic comparison of different regions of plasma, and plasmas are considered with linear dimensions varying from laboratory size up to the Hubble distance. The traditional magnetic field description of plasmas is supplemented by an electric current description and it is demonstrated that many problems are easier to understand with a dualistic approach. Using the general plasma properties obtained, the origin and evolution of the solar system is summarized and the evolution and present structure of the universe (cosmology) is discussed.

  5. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A relativistic electron beam generator or accelerator produces a high-voltage electron beam which is modulated to initiate electron bunching within the beam which is then applied to a high-density target plasma which typically comprises DT, DD, or similar thermonuclear gas at a density of 10 17 to 10 20 electrons per cubic centimeter. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region of the high-density plasma target. The high-temperature plasma can be used to heat a high Z material to generate radiation. Alternatively, a tunable radiation source is produced by using a moderate Z gas or a mixture of high Z and low Z gas as the target plasma. (author)

  6. Particle flows to shape and voltage surface discontinuities in the electron sheath surrounding a high voltage solar array in LEO

    Science.gov (United States)

    Metz, Roger N.

    1991-01-01

    This paper discusses the numerical modeling of electron flows from the sheath surrounding high positively biased objects in LEO (Low Earth Orbit) to regions of voltage or shape discontinuity on the biased surfaces. The sheath equations are derived from the Two-fluid, Warm Plasma Model. An equipotential corner and a plane containing strips of alternating voltage bias are treated in two dimensions. A self-consistent field solution of the sheath equations is outlined and is pursued through one cycle. The electron density field is determined by numerical solution of Poisson's equation for the electrostatic potential in the sheath using the NASCAP-LEO relation between electrostatic potential and charge density. Electron flows are calculated numerically from the electron continuity equation. Magnetic field effects are not treated.

  7. A permeability barrier surrounds taste buds in lingual epithelia

    Science.gov (United States)

    Dando, Robin; Pereira, Elizabeth; Kurian, Mani; Barro-Soria, Rene; Chaudhari, Nirupa

    2014-01-01

    Epithelial tissues are characterized by specialized cell-cell junctions, typically localized to the apical regions of cells. These junctions are formed by interacting membrane proteins and by cytoskeletal and extracellular matrix components. Within the lingual epithelium, tight junctions join the apical tips of the gustatory sensory cells in taste buds. These junctions constitute a selective barrier that limits penetration of chemosensory stimuli into taste buds (Michlig et al. J Comp Neurol 502: 1003–1011, 2007). We tested the ability of chemical compounds to permeate into sensory end organs in the lingual epithelium. Our findings reveal a robust barrier that surrounds the entire body of taste buds, not limited to the apical tight junctions. This barrier prevents penetration of many, but not all, compounds, whether they are applied topically, injected into the parenchyma of the tongue, or circulating in the blood supply, into taste buds. Enzymatic treatments indicate that this barrier likely includes glycosaminoglycans, as it was disrupted by chondroitinase but, less effectively, by proteases. The barrier surrounding taste buds could also be disrupted by brief treatment of lingual tissue samples with DMSO. Brief exposure of lingual slices to DMSO did not affect the ability of taste buds within the slice to respond to chemical stimulation. The existence of a highly impermeable barrier surrounding taste buds and methods to break through this barrier may be relevant to basic research and to clinical treatments of taste. PMID:25209263

  8. A permeability barrier surrounds taste buds in lingual epithelia.

    Science.gov (United States)

    Dando, Robin; Pereira, Elizabeth; Kurian, Mani; Barro-Soria, Rene; Chaudhari, Nirupa; Roper, Stephen D

    2015-01-01

    Epithelial tissues are characterized by specialized cell-cell junctions, typically localized to the apical regions of cells. These junctions are formed by interacting membrane proteins and by cytoskeletal and extracellular matrix components. Within the lingual epithelium, tight junctions join the apical tips of the gustatory sensory cells in taste buds. These junctions constitute a selective barrier that limits penetration of chemosensory stimuli into taste buds (Michlig et al. J Comp Neurol 502: 1003-1011, 2007). We tested the ability of chemical compounds to permeate into sensory end organs in the lingual epithelium. Our findings reveal a robust barrier that surrounds the entire body of taste buds, not limited to the apical tight junctions. This barrier prevents penetration of many, but not all, compounds, whether they are applied topically, injected into the parenchyma of the tongue, or circulating in the blood supply, into taste buds. Enzymatic treatments indicate that this barrier likely includes glycosaminoglycans, as it was disrupted by chondroitinase but, less effectively, by proteases. The barrier surrounding taste buds could also be disrupted by brief treatment of lingual tissue samples with DMSO. Brief exposure of lingual slices to DMSO did not affect the ability of taste buds within the slice to respond to chemical stimulation. The existence of a highly impermeable barrier surrounding taste buds and methods to break through this barrier may be relevant to basic research and to clinical treatments of taste. Copyright © 2015 the American Physiological Society.

  9. Mutual seismic interaction between tunnels and the surrounding granular soil

    Directory of Open Access Journals (Sweden)

    Mohamed Ahmed Abdel-Motaal

    2014-12-01

    Study results show that the maximum exerted straining actions in tunnel lining are directly proportional to the relative stiffness between tunnel and surrounding soil (lining thickness and soil shear modulus. Moreover, it is highly affected by the peak ground acceleration and the tunnel location (embedment depth. A comprehensive study is performed to show the effect of tunnel thickness and tunnel diameter on both the induced bending moment and lining deformation. In general, it is concluded that seismic analysis should be considered in regions subjected to peak ground acceleration greater than 0.15g.

  10. Remote and direct plasma regions for low-temperature growth of carbon nanotubes on glass substrates for display applications

    International Nuclear Information System (INIS)

    Tabatabaei, M K; Ghafouri fard, H; Koohsorkhi, J; Khatami, S; Mohajerzadeh, S

    2011-01-01

    A novel method for growing carbon nanotubes (CNTs) on glass substrates is introduced in this study. A two-stage plasma was used to achieve low-temperature and vertically aligned CNTs. Ni deposited on indium tin oxide/glass substrate was used as the catalyst and hydrogen and acetylene were used as gas feeds. In this investigation a new technique was developed to grow vertically aligned CNTs at temperatures below 400 deg. C while CNT growth by plasma-enhanced chemical vapour deposition required high temperatures. Low-temperature growth of vertically aligned CNTs was suitable for the fabrication of micro-lens and self-oriented displays on glass substrates. Also, we have reported a new configuration for CNT-based display by means of controlling the refractive index of liquid crystal around the CNT by applying a proper voltage to the top and bottom array.

  11. Gyrokinetic particle simulation of neoclassical transport in the pedestal/scrape-off region of a tokamak plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ku, S [Courant Institute of Mathematical Sciences, New York University (United States); Chang, C-S [Courant Institute of Mathematical Sciences, New York University (United States); Adams, M [Columbia University (United States); Cummings, J [California Institute of Technology (United States); Hinton, F [Hinton Associates (United States); Keyes, D [Columbia University (United States); Klasky, S [Oak Ridge National Laboratory (United States); Lee, W [Princeton Plasma Physics Laboratory (United States); Lin, Z [University of California at Irvine (United States); Parker, S [University of Colorado at Boulder (United States)

    2006-09-15

    A gyrokinetic neoclassical solution for a diverted tokamak edge plasma has been obtained for the first time using the massively parallel Jaguar XT3 computer at Oak Ridge National Laboratory. The solutions show similar characteristics to the experimental observations: electric potential is positive in the scrape-off layer and negative in the H-mode layer, and the parallel rotation is positive in the scrape-off layer and at the inside boundary of the H-mode layer. However, the solution also makes a new physical discovery that there is a strong ExB convective flow in the scrape-off plasma. A general introduction to the edge simulation problem is also presented.

  12. Interpretation of magnetosonic waves in the boundary regions of the plasma sheet as seen by the ISEE 3 spacecraft

    International Nuclear Information System (INIS)

    Smith, P.R.; Hopcraft, K.I.; Murphy, N.

    1987-01-01

    Recent calculations that derive the normal-mode spectrum of an idealized magnetic current sheet are discussed. The Harris neutral-sheet equilibrium is perturbed with an ideal MHD displacement. The longitudinal polarization of the fundamental modes is calculated as a function of the position in the sheet. Using data from the energetic-ion instrument aboard ISEE 3, the thickness of the plasma sheet in the deep geomagnetic tail is estimated. This parameter enables a quantitative comparison between the boundary oscillations reported by Tsurutani and Smith (1984) and the normal mode oscillations derived by Hopcraft and Smith (1985) to be performed. The normal-mode solutions are found to be consistent with observation. Further aspects of the MHD wave spectrum that may lead to an observable variation of the mode character across the boundary of the plasma sheet are pointed out. 12 references

  13. Physics of plasma etching and plasma deposition

    NARCIS (Netherlands)

    Schram, D.C.; Hoog, de F.J.; Bisschops, T.J.; Kroesen, G.M.W.; Howorka, F.; Lindinger, W.; Maerk, T.D.

    1986-01-01

    The kinetics and mechanism of the title processes are discussed on the basis of a model in which the plasma-surface system is subdivided into 5 regions: (I) plasma prodn., (II) plasma flow plus radicals, (III) gas adsorbed layer, (IV) modified surface, and (V) undisturbed solid (or liq.) state.

  14. Recombining processes in a cooling plasma by mixing of initially heated gas

    International Nuclear Information System (INIS)

    Furukane, Utaro; Sato, Kuninori; Takiyama, Ken; Oda, Toshiatsu.

    1992-03-01

    A numerical investigation of recombining process in a high temperature plasma in a quasi-steady state is made in a gas contact cooling, in which the initial temperature effect of contact gas heated up by the hot plasma is considered as well as the gas cooling due to the surrounding neutral particles freely coming into the plasma. The calculation has shown that the electron temperature relaxes in accord with experimental results and that the occurrence of recombining region and the inverted populations almost agree with the experimental ones. (author)

  15. Influence of surrounding environment on subcritical crack growth in marble

    Science.gov (United States)

    Nara, Yoshitaka; Kashiwaya, Koki; Nishida, Yuki; , Toshinori, Ii

    2017-06-01

    Understanding subcritical crack growth in rock is essential for determining appropriate measures to ensure the long-term integrity of rock masses surrounding structures and for construction from rock material. In this study, subcritical crack growth in marble was investigated experimentally, focusing on the influence of the surrounding environment on the relationship between the crack velocity and stress intensity factor. The crack velocity increased with increasing temperature and/or relative humidity. In all cases, the crack velocity increased with increasing stress intensity factor. However, for Carrara marble (CM) in air, we observed a region in which the crack velocity still increased with temperature, but the increase in the crack velocity with increasing stress intensity factor was not significant. This is similar to Region II of subcritical crack growth observed in glass in air. Region II in glass is controlled by mass transport to the crack tip. In the case of rock, the transport of water to the crack tip is important. In general, Region II is not observed for subcritical crack growth in rock materials, because rocks contain water. Because the porosity of CM is very low, the amount of water contained in the marble is also very small. Therefore, our results imply that we observed Region II in CM. Because the crack velocity increased in both water and air with increasing temperature and humidity, we concluded that dry conditions at low temperature are desirable for the long-term integrity of a carbonate rock mass. Additionally, mass transport to the crack tip is an important process for subcritical crack growth in rock with low porosity.

  16. Sequencing analysis of ghrelin gene 5' flanking region: relations between the sequence variants, fasting plasma total ghrelin concentrations, and body mass index.

    Science.gov (United States)

    Vartiainen, Johanna; Kesäniemi, Y Antero; Ukkola, Olavi

    2006-10-01

    Ghrelin is a 28-amino-acid peptide with several functions linked to energy metabolism. Low ghrelin plasma concentrations are associated with obesity, hypertension, and type 2 diabetes mellitus, whereas high concentrations reflect states of negative energy balance. Several studies addressing the hormonal and neural regulation of ghrelin gene expression have been carried out, but the role of genetic factors in the regulation of ghrelin plasma levels remains unclear. To elucidate the role of genetic factors in the regulation of ghrelin expression, we screened 1657 nucleotides of the ghrelin gene 5' flanking region (promoter and possible regulatory sites) for new sequential variations from patient samples with low (n = 50) and high (n = 50) fasting plasma total ghrelin concentrations (low- and high-ghrelin groups). Eleven single nucleotide polymorphisms (SNPs), 3 of which were rare variants (allelic frequency less than 1%) were found in our population. The genotype distribution patterns of the SNPs did not differ between the study groups, except for SNP-501A>C (P = .039). In addition, the SNP-01A>C was associated with body mass index (BMI) (P = .018). This variant was studied further in our large and well-defined Oulu Project Elucidating Risk for Atherosclerosis (OPERA) cohort (n = 1045) by the restriction fragment length polymorphism (RFLP) technique. No significant association of SNP-501A>C genotypes with fasting ghrelin plasma concentrations was found in the whole OPERA population. However, the association of this SNP with BMI and with waist circumference reached statistical significance in OPERA (P = .047 and .049, respectively), remaining of borderline significance for BMI after adjustments (P = .055). The results indicate that factors other than the 11 SNPs found in this study in the 5' flanking region of ghrelin gene are the main determinants of ghrelin plasma levels. However, SNP-501 A>C genotype distribution seems to be different in subjects having the highest

  17. Examples of plasma horizons

    International Nuclear Information System (INIS)

    Hanni, R.S.

    1975-01-01

    The concept of the plasma horizon, defined as the boundary of the region in which an infinitely thin plasma can be supported against Coulomb attraction by a magnetic field, shows that the argument of selective accretion does not rule out the existence of charged black holes embedded in a conducting plasma. A detailed account of the covariant definition of plasma horizon is given and some examples of plasma horizons are presented. 7 references

  18. The N-terminal region of the dopamine D2 receptor, a rhodopsin-like GPCR, regulates correct integration into the plasma membrane and endocytic routes

    Science.gov (United States)

    Cho, DI; Min, C; Jung, KS; Cheong, SY; Zheng, M; Cheong, SJ; Oak, MH; Cheong, JH; Lee, BK; Kim, KM

    2012-01-01

    BACKGROUND AND PURPOSE Functional roles of the N-terminal region of rhodopsin-like GPCR family remain unclear. Using dopamine D2 and D3 receptors as a model system, we probed the roles of the N-terminal region in the signalling, intracellular trafficking of receptor proteins, and explored the critical factors that determine the functionality of the N-terminal region. EXPERIMENTAL APPROACH The N-terminal region of the D2 receptor was gradually shortened or switched with that of the D3 receptor or a non-specific sequence (FLAG), or potential N-terminal glycosylation sites were mutated. Effects of these manipulations on surface expression, internalization, post-endocytic behaviours and signalling were determined. KEY RESULTS Shortening the N-terminal region of the D2 receptor enhanced receptor internalization and impaired surface expression and signalling; ligand binding, desensitization and down-regulation were not affected but their association with a particular microdomain, caveolae, was disrupted. Replacement of critical residues within the N-terminal region with the FLAG epitope failed to restore surface expression but partially restored the altered internalization and signalling. When the N-terminal regions were switched between D2 and D3 receptors, cell surface expression pattern of each receptor was switched. Mutations of potential N-terminal glycosylation sites inhibited surface expression but enhanced internalization of D2 receptors. CONCLUSIONS AND IMPLICATIONS Shortening of N-terminus or mutation of glycosylation sites located within the N-terminus enhanced receptor internalization but impaired the surface expression of D2 receptors. The N-terminal region of the D2 receptor, in a sequence-specific manner, controls the receptor's conformation and integration into the plasma membrane, which determine its subcellular localization, intracellular trafficking and signalling properties. PMID:22117524

  19. Simultaneous observations of equatorial F-region plasma depletions over Brazil during the Spread-F Experiment (SpreadFEx

    Directory of Open Access Journals (Sweden)

    P.-D. Pautet

    2009-06-01

    Full Text Available From September to November 2005, the NASA Living with a Star program supported the Spread-F Experiment campaign (SpreadFEx in Brazil to study the effects of convectively generated gravity waves on the ionosphere and their role in seeding Rayleigh-Taylor instabilities, and associated equatorial plasma bubbles. Several US and Brazilian institutes deployed a broad range of instruments (all-sky imagers, digisondes, photometers, meteor/VHF radars, GPS receivers covering a large area of Brazil. The campaign was divided in two observational phases centered on the September and October new moon periods. During these periods, an Utah State University (USU all-sky CCD imager operated at São João d'Aliança (14.8° S, 47.6° W, near Brasilia, and a Brazilian all-sky CCD imager located at Cariri (7.4° S, 36° W, observed simultaneously the evolution of the ionospheric bubbles in the OI (630 nm emission and the mesospheric gravity wave field. The two sites had approximately the same magnetic latitude (9–10° S but were separated in longitude by ~1500 km.

    Plasma bubbles were observed on every clear night (17 from Brasilia and 19 from Cariri, with 8 coincident nights. These joint datasets provided important information for characterizing the ionospheric depletions during the campaign and to perform a novel longitudinal investigation of their variability. Measurements of the drift velocities at both sites are in good agreement with previous studies, however, the overlapping fields of view revealed significant differences in the occurrence and structure of the plasma bubbles, providing new evidence for localized generation. This paper summarizes the observed bubble characteristics important for related investigations of their seeding mechanisms associated with gravity wave activity.

  20. Simultaneous observations of equatorial F-region plasma depletions over Brazil during the Spread-F Experiment (SpreadFEx

    Directory of Open Access Journals (Sweden)

    P.-D. Pautet

    2009-06-01

    Full Text Available From September to November 2005, the NASA Living with a Star program supported the Spread-F Experiment campaign (SpreadFEx in Brazil to study the effects of convectively generated gravity waves on the ionosphere and their role in seeding Rayleigh-Taylor instabilities, and associated equatorial plasma bubbles. Several US and Brazilian institutes deployed a broad range of instruments (all-sky imagers, digisondes, photometers, meteor/VHF radars, GPS receivers covering a large area of Brazil. The campaign was divided in two observational phases centered on the September and October new moon periods. During these periods, an Utah State University (USU all-sky CCD imager operated at São João d'Aliança (14.8° S, 47.6° W, near Brasilia, and a Brazilian all-sky CCD imager located at Cariri (7.4° S, 36° W, observed simultaneously the evolution of the ionospheric bubbles in the OI (630 nm emission and the mesospheric gravity wave field. The two sites had approximately the same magnetic latitude (9–10° S but were separated in longitude by ~1500 km. Plasma bubbles were observed on every clear night (17 from Brasilia and 19 from Cariri, with 8 coincident nights. These joint datasets provided important information for characterizing the ionospheric depletions during the campaign and to perform a novel longitudinal investigation of their variability. Measurements of the drift velocities at both sites are in good agreement with previous studies, however, the overlapping fields of view revealed significant differences in the occurrence and structure of the plasma bubbles, providing new evidence for localized generation. This paper summarizes the observed bubble characteristics important for related investigations of their seeding mechanisms associated with gravity wave activity.

  1. Composite films prepared by plasma ion-assisted deposition (IAD) for design and fabrication of antireflection coatings in visible and near-infrared spectral regions

    Science.gov (United States)

    Tsai, Rung-Ywan; Ho, Fang C.

    1994-11-01

    Ion-assisted deposition (IAD) processes configured with a well-controlled plasma source at the center base of a vacuum chamber, which accommodates two independent e-gun sources, is used to deposition TiO2MgF2 and TiO2-SiO2 composite films of selected component ratios. Films prepared by this technology are found durable, uniform, and nonabsorbing in visible and near-IR regions. Single- and multilayer antireflection coatings with refractive index from 1.38 to 2.36 at (lambda) equals 550 nm are presented. Methods of enhancement in optical performance of these coatings are studied. The advantages of AR coatings formed by TiO2-MgF2 composite films over those similar systems consisting of TiO2-SiO2 composite films in both visible and near-IR regions are also presented.

  2. Experimental evidence of significant temperature fluctuations in the plasma EDGE region of the TJ-I Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, C; Balbin, R; Pedrosa, M A; Garcia-Cortes, I; Ochando, M A

    1993-07-01

    Density and temperature fluctuations have been measured in the plasma bulk side of the velocity shear location of the TJ-I tokamak using a feast swept Langmuir probe technique. Evidence of substantial temperature fluctuations which are in phase close to opposition with the corresponding density fluctuations has been found. This result suggests the possible role of radiation in determining edge fluctuation levels and call into question the determination of the density and potential fluctuations from the Langmuir current-probe and floating potential fluctuations. (Author) 16 refs.

  3. Experimental evidence of significant temperature fluctuations in the plasma edge region of the TJ-I Tokamak

    International Nuclear Information System (INIS)

    Hidalgo, C.; Balbin, R.; Pedrosa, M.A.; Garcia-Cortes, I.; Ochando, M.A.

    1993-01-01

    Density and temperature fluctuations have been measured in the plasma bulk side of the velocity shear location of the TJ-I tokamak using a foast swept Langmuir probe technique. Evidence of sustantial temperature fluctuations which are in phase close to opposition with the corresponding density fluctuations has been found. This result suggests the possible role of radiation in determining edge fluctuation levels and call into question the determination of the density and potential fluctuations from the Langmuir current-probe and floating potential fluctuations. (Author)

  4. Experimental evidence of significant temperature fluctuations in the plasma EDGE region of the TJ-I Tokamak

    International Nuclear Information System (INIS)

    Hidalgo, C.; Balbin, R.; Pedrosa, M. A.; Garcia-Cortes, I.; Ochando, M. A.

    1993-01-01

    Density and temperature fluctuations have been measured in the plasma bulk side of the velocity shear location of the TJ-I tokamak using a feast swept Langmuir probe technique. Evidence of substantial temperature fluctuations which are in phase close to opposition with the corresponding density fluctuations has been found. This result suggests the possible role of radiation in determining edge fluctuation levels and call into question the determination of the density and potential fluctuations from the Langmuir current-probe and floating potential fluctuations. (Author) 16 refs

  5. Effects of a precursor plasma on a coaxial-to-radial transition discharge

    International Nuclear Information System (INIS)

    Enloe, C.L.; Reinovsky, R.E.

    1985-01-01

    The Quick-Fire series of experiments on the AFWL SHIVA-Star 9.6 megajoule capacitor bank utilizes a coaxial plasma gun as a power conditioning and switching element driving an imploding plasma liner in what is essentially a hollow z-pinch. Initially, the liner is a thin, cylindrical plastic-and-metal foil. Ideally, the foil remains undisturbed until switching action occurs, and steps have been taken to minimize the amount of hot material that is accelerated into the plasma region ahead of the main coaxial discharge. The condition of the foil and the surrounding region prior to switching has been studied both with nitrogen laser shadowgraphy and with a technique which measures the deflection of a helium-neon laser beam due to the presence of density gradients in the switching region. Estimates of the density of precursor plasmas and their effects on foil condition are presented

  6. Prognostic Value of Plasma Epstein-Barr Virus DNA for Local and Regionally Advanced Nasopharyngeal Carcinoma Treated With Cisplatin-Based Concurrent Chemoradiotherapy in Intensity-Modulated Radiotherapy Era.

    Science.gov (United States)

    Chen, Wen-Hui; Tang, Lin-Quan; Guo, Shan-Shan; Chen, Qiu-Yan; Zhang, Lu; Liu, Li-Ting; Qian, Chao-Nan; Guo, Xiang; Xie, Dan; Zeng, Mu-Sheng; Mai, Hai-Qiang

    2016-02-01

    This study aimed to evaluate the prognostic value of plasma Epstein-Barr Virus DNA (EBV DNA) for local and regionally advanced nasopharyngeal carcinoma (NPC) patients treated with concurrent chemoradiotherapy in intensity-modulated radiotherapy (IMRT) era.In this observational study, 404 nonmetastatic local and regionally advanced NPC patients treated with IMRT and cisplatin-based concurrent chemotherapy were recruited. Blood samples were collected before treatment for examination of plasma EBV DNA levels. We evaluated the association of pretreatment plasma EBV DNA levels with progression-free survival rate (PFS), distant metastasis-free survival rate (DMFS), and overall survival rate (OS).Compared to patients with an EBV DNA level advanced NPC patients treated with IMRT and cisplatin-based concurrent chemotherapy. Future ramdomized clinical trials are needed to further evaluate whether plasma EBV DNA levels could be applied to guide concurrent chemotherapy regimen for local and regionally advanced NPC patients.

  7. Single point mutations distributed in 10 soluble and membrane regions of the Nicotiana plumbaginifolia plasma membrane PMA2 H+-ATPase activate the enzyme and modify the structure of the C-terminal region.

    Science.gov (United States)

    Morsomme, P; Dambly, S; Maudoux, O; Boutry, M

    1998-12-25

    The Nicotiana plumbaginifolia pma2 (plasma membrane H+-ATPase) gene is capable of functionally replacing the H+-ATPase genes of the yeast Saccharomyces cerevisiae, provided that the external pH is kept above 5.0. Single point mutations within the pma2 gene were previously identified that improved H+-ATPase activity and allowed yeast growth at pH 4.0. The aim of the present study was to identify most of the PMA2 positions, the mutation of which would lead to improved growth and to determine whether all these mutations result in similar enzymatic and structural modifications. We selected additional mutants in total 42 distinct point mutations localized in 30 codons. They were distributed in 10 soluble and membrane regions of the enzyme. Most mutant PMA2 H+-ATPases were characterized by a higher specific activity, lower inhibition by ADP, and lower stimulation by lysophosphatidylcholine than wild-type PMA2. The mutants thus seem to be constitutively activated. Partial tryptic digestion and immunodetection showed that the PMA2 mutants had a conformational change making the C-terminal region more accessible. These data therefore support the hypothesis that point mutations in various H+-ATPase parts displace the inhibitory C-terminal region, resulting in enzyme activation. The high density of mutations within the first half of the C-terminal region suggests that this part is involved in the interaction between the inhibitory C-terminal region and the rest of the enzyme.

  8. TRIGGERED STAR FORMATION SURROUNDING WOLF-RAYET STAR HD 211853

    Energy Technology Data Exchange (ETDEWEB)

    Liu Tie; Wu Yuefang; Zhang Huawei [Department of Astronomy, Peking University, 100871 Beijing (China); Qin Shengli, E-mail: liutiepku@gmail.com [I. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Koeln (Germany)

    2012-05-20

    The environment surrounding Wolf-Rayet (W-R) star HD 211853 is studied in molecular, infrared, as well as radio, and H I emission. The molecular ring consists of well-separated cores, which have a volume density of 10{sup 3} cm{sup -3} and kinematic temperature {approx}20 K. Most of the cores are under gravitational collapse due to external pressure from the surrounding ionized gas. From the spectral energy distribution modeling toward the young stellar objects, the sequential star formation is revealed on a large scale in space spreading from the W-R star to the molecular ring. A small-scale sequential star formation is revealed toward core 'A', which harbors a very young star cluster. Triggered star formations are thus suggested. The presence of the photodissociation region, the fragmentation of the molecular ring, the collapse of the cores, and the large-scale sequential star formation indicate that the 'collect and collapse' process functions in this region. The star-forming activities in core 'A' seem to be affected by the 'radiation-driven implosion' process.

  9. TRIGGERED STAR FORMATION SURROUNDING WOLF-RAYET STAR HD 211853

    International Nuclear Information System (INIS)

    Liu Tie; Wu Yuefang; Zhang Huawei; Qin Shengli

    2012-01-01

    The environment surrounding Wolf-Rayet (W-R) star HD 211853 is studied in molecular, infrared, as well as radio, and H I emission. The molecular ring consists of well-separated cores, which have a volume density of 10 3 cm –3 and kinematic temperature ∼20 K. Most of the cores are under gravitational collapse due to external pressure from the surrounding ionized gas. From the spectral energy distribution modeling toward the young stellar objects, the sequential star formation is revealed on a large scale in space spreading from the W-R star to the molecular ring. A small-scale sequential star formation is revealed toward core 'A', which harbors a very young star cluster. Triggered star formations are thus suggested. The presence of the photodissociation region, the fragmentation of the molecular ring, the collapse of the cores, and the large-scale sequential star formation indicate that the 'collect and collapse' process functions in this region. The star-forming activities in core 'A' seem to be affected by the 'radiation-driven implosion' process.

  10. Crust Structure Data of Seas Surrounding Turkey

    International Nuclear Information System (INIS)

    Maden, N.; Gelisli, K.

    2007-01-01

    Black Sea, Aegean, Mediterranean and Marmara Sea, which surround the Turkey, have not been examined with respect to the Geological, Geophysical and other natural sciences sufficiently. In fact, it is not attach importance the Turkish seas adequately and abandoned with respect to the scientific researches. The most important reason of this situation is the lack of the education of the Marine Sciences in the Turkish Universities. In this study, it is tried to construct a crustal structure data base of the surrounding seas of the Turkey by collecting crustal structure data sets done by different authors in different times so far. The data acquired in the base are collected from different data base sources by dragging. The Moho depth in the eastern and western basin of the Black sea is 22 km and 19 km, respectively. In the Marmara Sea the Moho depth is 24 km. The moho value in the southern Aegean is 20 km, in the northern Aegean the moho depth is 30 km. on the other hand, the moho depth value in the eastern and western basin of the Mediterranean Sea are 15-20 km and 25-30 km, respectively

  11. Superconducting plasmas

    International Nuclear Information System (INIS)

    Ohnuma, Toshiro; Ohno, J.

    1994-01-01

    Superconducting (SC) plasmas are proposed and investigated. The SC plasmas are not yet familiar and have not yet been studied. However, the existence and the importance of SC plasmas are stressed in this report. The existence of SC plasmas are found as follows. There is a fundamental property of Meissner effect in superconductors, which shows a repulsive effect of magnetic fields. Even in that case, in a microscopic view, there is a region of magnetic penetration. The penetration length λ is well-known as London's penetration depth, which is expressed as δ = (m s /μ 0 n s q s 2 ) 1/2 where m s , n s , q s and μ o show the mass, the density, the charge of SC electron and the permeability in free space, respectively. Because this expression is very simple, no one had tried it into more simple and meaningful form. Recently, one of the authors (T.O.) has found that the length can be expressed into more simple and understandable fundamental form as λ = c/ω ps where c = (ε 0 μ 0 ) -1/2 and ω ps = (n s q s 2 /m s ε 0 ) 1/2 are the light velocity and the superconducting plasma frequency. From this simple expression, the penetration depth of the magnetic field to SC is found as a SC plasma skin depth, that is, the fundamental property of SC can be expressed by the SC plasmas. This discovery indicates an importance of the studies of superconducting plasmas. From these points, several properties (propagating modes et al) of SC plasmas, which consist of SC electrons, normal electrons and lattice ions, are investigated in this report. Observations of SC plasma frequency is also reported with a use of Terahertz electromagnet-optical waves

  12. Physical geography of the Nete basin and surroundings

    International Nuclear Information System (INIS)

    Beerten, K.

    2011-01-01

    The report briefly describes the main features of the physical geography of the Nete basin (Campine region, Belgium) and its immediate surroundings. First, an integrated overview of the topography, morphology and hydrography is given. This overview serves as the basis for the assessment of the morphological stability of the region and also explains the relationship between the topography and the hydrology. Furthermore, special attention is paid to soil science including a quantitative survey of some soil characteristics data. Another part of this report deals with erosion processes caused by water and wind action, and the (potential) impact on the morphology. Finally, the palaeogeographical evolution during the Quaternary is discussed. This evolution shows that the environment is stable over 10 000 years or more in the current and similar climatic conditions. Altering climatic conditions, notably glacial-interglacial periods, have impacted erosion with periods of strong erosion.

  13. Arc Plasma Gun With Coaxial Powder Feed

    Science.gov (United States)

    Zaplatynsky, Isidor

    1988-01-01

    Redesigned plasma gun provides improved metallic and ceramic coatings. Particles injected directly through coaxial bore in cathode into central region of plasma jet. Introduced into hotter and faster region of plasma jet.

  14. Opportunity's Surroundings on Sol 1687 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 360-degree view of the rover's surroundings on the 1,687th Martian day, or sol, of its surface mission (Oct. 22, 2008). Opportunity had driven 133 meters (436 feet) that sol, crossing sand ripples up to about 10 centimeters (4 inches) tall. The tracks visible in the foreground are in the east-northeast direction. Opportunity's position on Sol 1687 was about 300 meters southwest of Victoria Crater. The rover was beginning a long trek toward a much larger crater, Endeavour, about 12 kilometers (7 miles) to the southeast. This view is presented as a vertical projection with geometric seam correction.

  15. Opportunity's Surroundings on Sol 1687 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this 360-degree view of the rover's surroundings on the 1,687th Martian day, or sol, of its surface mission (Oct. 22, 2008). Opportunity had driven 133 meters (436 feet) that sol, crossing sand ripples up to about 10 centimeters (4 inches) tall. The tracks visible in the foreground are in the east-northeast direction. Opportunity's position on Sol 1687 was about 300 meters southwest of Victoria Crater. The rover was beginning a long trek toward a much larger crater, Endeavour, about 12 kilometers (7 miles) to the southeast. This view is presented as a polar projection with geometric seam correction.

  16. Towards Semantic Understanding of Surrounding Vehicular Maneuvers

    DEFF Research Database (Denmark)

    Kristoffersen, Miklas Strøm; Dueholm, Jacob Velling; Satzoda, Ravi K.

    2016-01-01

    This paper proposes the use of multiple low-cost visual sensors to obtain a surround view of the ego-vehicle for semantic understanding. A multi-perspective view will assist the analysis of naturalistic driving studies (NDS), by automating the task of data reduction of the observed sequences...... into events. A user-centric vision-based framework is presented using a vehicle detector and tracker in each separate perspective. Multi-perspective trajectories are estimated and analyzed to extract 14 different events, including potential dangerous behaviors such as overtakes and cut-ins. The system...... is tested on ten sequences of real-world data collected on U. S. highways. The results show the potential use of multiple low-cost visual sensors for semantic understanding around the ego-vehicle....

  17. Lovelock black holes surrounded by quintessence

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sushant G. [University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Durban (South Africa); Centre for Theoretical Physics, Multidisciplinary Centre for Advanced Research and Studies (MCARS), New Delhi (India); Maharaj, Sunil D.; Baboolal, Dharmanand; Lee, Tae-Hun [University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Durban (South Africa)

    2018-02-15

    Lovelock gravity consisting of the dimensionally continued Euler densities is a natural generalization of general relativity to higher dimensions such that equations of motion are still second order, and the theory is free of ghosts. A scalar field with a positive potential that yields an accelerating universe has been termed quintessence. We present exact black hole solutions in D-dimensional Lovelock gravity surrounded by quintessence matter and also perform a detailed thermodynamical study. Further, we find that the mass, entropy and temperature of the black hole are corrected due to the quintessence background. In particular, we find that a phase transition occurs with a divergence of the heat capacity at the critical horizon radius, and that specific heat becomes positive for r{sub h} < r{sub c} allowing the black hole to become thermodynamically stable. (orig.)

  18. Lovelock black holes surrounded by quintessence

    Science.gov (United States)

    Ghosh, Sushant G.; Maharaj, Sunil D.; Baboolal, Dharmanand; Lee, Tae-Hun

    2018-02-01

    Lovelock gravity consisting of the dimensionally continued Euler densities is a natural generalization of general relativity to higher dimensions such that equations of motion are still second order, and the theory is free of ghosts. A scalar field with a positive potential that yields an accelerating universe has been termed quintessence. We present exact black hole solutions in D-dimensional Lovelock gravity surrounded by quintessence matter and also perform a detailed thermodynamical study. Further, we find that the mass, entropy and temperature of the black hole are corrected due to the quintessence background. In particular, we find that a phase transition occurs with a divergence of the heat capacity at the critical horizon radius, and that specific heat becomes positive for r_h

  19. Organization of cervical cancer screening in Campinas and surrounding region, São Paulo State, Brazil Organização do rastreamento do câncer do colo uterino em Campinas e região, São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Zeferino

    2006-09-01

    Full Text Available Cervical cancer screening remains a challenge in developing countries due to a complex array of problems. This paper aimed to describe the experience with organization of cervical cancer screening in three districts of Campinas and the surrounding region in São Paulo State, Brazil, and to report the resulting data. The program was organized in a pyramid format, and the health care hierarchy was defined according to the complexity and total number of medical procedures. Screening has been extended currently to 88 municipalities, of which 51 are equipped with colposcopy and eight have facilities for treating advanced cervical cancer. The standardized incidence rate for cervical cancer in Campinas was 14.2/100,000 women per year in 1993-1995, and the standardized mortality rate per district ranged from 2.7 to 3.0 per 100,000 women in 1997-1998. This project has clearly shown that hierarchical and decentralized organization of health procedures is a necessary condition for achieving the goals of an effective cervical cancer screening program.O programa de rastreamento do câncer do colo uterino ainda é um desafio para os países em desenvolvimento devido a uma série complexa de problemas. Este estudo objetivou descrever a experiência adquirida com a organização e mostrar alguns dados sobre o rastreamento deste câncer em três distritos de Campinas e região, São Paulo, Brasil. A hierarquia das ações de saúde foi estabelecida de acordo com a complexidade dos procedimentos e do total destes procedimentos que precisavam ser realizados. Atualmente, o rastreamento se estende a 88 municípios, dos quais 51 realizam colposcopia e oito têm serviços para tratar câncer avançado do colo uterino. A taxa de incidência ajustada em Campinas foi de 14,2/100 mil mulheres por ano em 1993-1995, e a taxa de mortalidade ajustada por distrito variou entre 2,7 e 3,0 por 100 mil mulheres em 1997-1998. De acordo com a experiência adquirida, a organiza

  20. From chemicals to cold plasma: Non-thermal food processing technologies research at the USDA's Eastern Regional Research Center

    Science.gov (United States)

    Foodborne pathogens cause millions of illnesses every year. At the US Department of Agriculture’s Eastern Regional Research Center, scientists and engineers have focused on developing new ways to improve food safety and shelf life while retaining quality and nutritional value. A variety of technolog...

  1. Electrodynamic coupling between pulsars and surrounding nebulae

    Energy Technology Data Exchange (ETDEWEB)

    Dobrowolny, M [Consiglio Nazionale delle Ricerche, Frascati (Italy). Lab. per il Plasma nello Spazio; L' Aquila Univ. (Italy). Istituto di Fisica); Ferrari, A [Cambridge Univ. (UK). Inst. of Astronomy; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Istituto di Fisica)

    1976-02-01

    In this work a study is presented of collective plasma processes by which pulsars can energetically support young supernova remnants. We show that many of the observed features of the Crab Nebula can be adequately interpreted in terms of a parametric interaction between the low-frequency electromagnetic wave emitted by the pulsar in the oblique rotator model and a relativistic wind of charged particle leaking from the pulsar's inner magnetosphere. In particular we show that there is a relativistic parametric resonant coupling of the strong wave with electrostatic and electromagnetic modes.

  2. Separate structure of two branches of sheared slab ηi mode and effects of plasma rotation shear in weak magnetic shear region

    International Nuclear Information System (INIS)

    Jiquan Li; Kishimoto, Y.; Tuda, T.

    2000-01-01

    The separate structure of two branches of the sheared slab η i mode near the minimum-q magnetic surface is analysed and the effects of plasma rotation shears are considered in the weak magnetic shear region. Results show that the separation condition depends on the non-monotonous q profile and the deviation of rational surface from the minimum-q surface. Furthermore, it is found that the diamagnetic rotation shear may suppress the perturbation of the sheared slab η i mode at one side of the minimum-q surface, the poloidal rotation shear from the sheared E-vector x B-vector flow has a similar role to the slab mode structure when it possesses a direction same as the diamagnetic shear. A plausible interrelation between the separate structures of the two branches of the sheared slab mode and the discontinuity or gap of the radially global structure of the drift wave near the minimum-q surface observed in the toroidal particle simulation (Kishimoto Y et al 1998 Plasma Phys. Control. Fusion 40 A663) is discussed. It seems to support such a viewpoint: the double or/and global branches of the sheared slab η i mode near the minimum-q surface may become a bridge to connect the radially global structures of the drift wave at two sides of the minimum-q surface and the discontinuity may originate from the separate structures of these slab modes for a flatter q profile. (author)

  3. How A Black Hole Lights Up Its Surroundings

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    How do the supermassive black holes that live at the centers of galaxies influence their environments? New observations of a distant active galaxy offer clues about this interaction.Signs of CoevolutionPlot demonstrating the m-sigma relation, the empirical correlation between the stellar velocity dispersion of a galactic bulge and the mass of the supermassive black hole at its center. [Msigma]We know that the centers of active galaxies host supermassive black holes with masses of millions to billions of suns. One mystery surrounding these beasts is that they are observed to evolve simultaneously with their host galaxies for instance, an empirical relationship is seen between the growth of a black hole and the growth of its host galaxys bulge. This suggests that there must be a feedback mechanism through which the evolution of a black hole is linked to that of its host galaxy.One proposed source of this coupling is the powerful jets emitted from the poles of these supermassive black holes. These jets are thought to be produced as some of the material accreting onto the black hole is flung out, confined by surrounding gas and magnetic fields. Because the jets of hot gas and radiation extend outward through the host galaxy, they provide a means for the black hole to influence the gas and dust of its surroundings.In our current model of a radio-loud active galactic nuclei,a region of hot, ionized gas the narrow-line region lies beyond the sphere of influence of the supermassive black hole. [C.M. Urry and P. Padovani]Clues in the Narrow-Line RegionThe region of gas thought to sit just outside of the black holes sphere of influence (at a distance of perhaps a thousand to a few thousand light-years) is known as the narrow line region so named because we observe narrow emission lines from this gas. Given its hot, ionized state, this gas must somehow be being pummeled with energy. In the canonical picture, radiation from the black hole heats the gas directly in a process

  4. Laser fluorescence spectroscopy by two-photon excitation for detection of hydrogen atoms in a periphery region of high temperature plasmas

    International Nuclear Information System (INIS)

    Kim, Hee-Je; Kajiwara, Toshinori; Motoyama, Sumio; Muraoka, Katsunori; Akazaki, Masanori; Okada, Tatsuo; Maeda, Mitsuo

    1989-01-01

    For measurements of atomic hydrogen density in the periphery region of high temperature plasmas, laser fluorescence spectroscopy (LFS) by two-photon excitation (1s-3s, 3d) was developed. Based upon the theoretical estimates for laser source requirements, which indicated the laser energy and spectral width to be more than 10 mJ (assuming the pulse duration of 10 ns) and several tens of picometers around the wavelength of 205.1 nm, respectively, the first Stokes generation in deuterium gas of ArF laser output was adopted and shown to have the necessary performance. Through the LFS experiment employing the laser source, the minimum detectable limit of atomic hydrogen, normalized by a laser power and an observing solid angle, was demonstrated to be 1 x 10 14 [m -3 · MW · sr], which is usually sufficient for the above purpose, and the accuracy of the density determination was shown to be within a factor 2. (author)

  5. Opportunity's Surroundings on Sol 1687 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11739 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11739 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, 360-degree view of the rover's surroundings on the 1,687th Martian day, or sol, of its surface mission (Oct. 22, 2008). The view appears three-dimensional when viewed through red-blue glasses. Opportunity had driven 133 meters (436 feet) that sol, crossing sand ripples up to about 10 centimeters (4 inches) tall. The tracks visible in the foreground are in the east-northeast direction. Opportunity's position on Sol 1687 was about 300 meters southwest of Victoria Crater. The rover was beginning a long trek toward a much larger crater, Endeavour, about 12 kilometers (7 miles) to the southeast. This panorama combines right-eye and left-eye views presented as cylindrical-perspective projections with geometric seam correction.

  6. Alterations in blood glucose and plasma glucagon concentrations during deep brain stimulation in the shell region of the nucleus accumbens in rats

    Directory of Open Access Journals (Sweden)

    Charlene eDiepenbroek

    2013-12-01

    Full Text Available Deep brain stimulation (DBS of the nucleus accumbens (NAc is an effective therapy for obsessive compulsive disorder (OCD and is currently under investigation as a treatment for eating disorders. DBS of this area is associated with altered food intake and pharmacological treatment of OCD is associated with the risk of developing type 2 diabetes. Therefore we examined if DBS of the NAc-shell (sNAc influences glucose metabolism. Male Wistar rats were subjected to DBS, or sham stimulation, for a period of one hour. To assess the effects of stimulation on blood glucose and glucoregulatory hormones, blood samples were drawn before, during and after stimulation. Subsequently, all animals were used for quantitative assessment of Fos immunoreactivity in the lateral hypothalamic area (LHA using computerized image analysis. DBS of the sNAc rapidly increased plasma concentrations of glucagon and glucose while sham stimulation and DBS outside the sNAc were ineffective. In addition, the increase in glucose was dependent on DBS intensity. In contrast, the DBS-induced increase in plasma corticosterone concentrations was independent of intensity and region, indicating that the observed DBS-induced metabolic changes were not due to corticosterone release. Stimulation of the sNAc with 200 μA increased Fos immunoreactivity in the LHA compared to sham or 100 μA stimulated animals. These data show that DBS of the sNAc alters glucose metabolism in a region- and intensity dependent manner in association with neuronal activation in the LHA. Moreover, these data illustrate the need to monitor changes in glucose metabolism during DBS-treatment of OCD patients.

  7. Biogeography of azooxanthellate corals in the Caribbean and surrounding areas

    Science.gov (United States)

    Dawson, J.

    2002-04-01

    Biogeographic patterns for azooxanthellate corals are not as well known as those of zooxanthellate (primarily reef-building) corals. I analyzed occurrences of 129 species of azooxanthellate corals in 19 geopolitical regions in the Caribbean and surrounding areas. I performed an unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis using Bray-Curtis' similarity measure on the complete data set and shallow- and deep-water subsets of the data. The results indicate two provinces, each with a widespread (tropical and subtropical distributions) component to its fauna. One province has a tropical and primarily insular component to it, while the other has a subtropical and primarily continental component. By contrast, zooxanthellate corals have a uniform faunal composition throughout the Caribbean. Moreover, zooxanthellate corals have half as many species in the Caribbean as the azooxanthellate corals even though their global diversities are equal. These differences in diversity and geographic distribution patterns should be considered when developing conservation strategies.

  8. Understanding community norms surrounding tobacco sales.

    Directory of Open Access Journals (Sweden)

    Patricia A McDaniel

    Full Text Available In the US, denormalizing tobacco use is key to tobacco control; less attention has been paid to denormalizing tobacco sales. However, some localities have placed limits on the number and type of retailers who may sell tobacco, and some retailers have abandoned tobacco sales voluntarily. Understanding community norms surrounding tobacco sales may help accelerate tobacco denormalization.We conducted 15 focus groups with customers of California, New York, and Ohio retailers who had voluntarily discontinued tobacco sales to examine normative assumptions about where cigarettes should or should not be sold, voluntary decisions to discontinue tobacco sales, and government limits on such sales.Groups in all three states generally agreed that grocery stores that sold healthy products should not sell tobacco; California groups saw pharmacies similarly, while this was a minority opinion in the other two states. Convenience stores were regarded as a natural place to sell tobacco. In each state, it was regarded as normal and commendable for some stores to want to stop selling tobacco, although few participants could imagine convenience stores doing so. Views on government's role in setting limits on tobacco sales varied, with California and New York participants generally expressing support for restrictions, and Ohio participants expressing opposition. However, even those who expressed opposition did not approve of tobacco sales in all possible venues. Banning tobacco sales entirely was not yet normative.Limiting the ubiquitous availability of tobacco sales is key to ending the tobacco epidemic. Some limits on tobacco sales appear to be normative from the perspective of community members; it may be possible to shift norms further by problematizing the ubiquitous presence of cigarettes and drawing connections to other products already subject to restrictions.

  9. Understanding community norms surrounding tobacco sales.

    Science.gov (United States)

    McDaniel, Patricia A; Malone, Ruth E

    2014-01-01

    In the US, denormalizing tobacco use is key to tobacco control; less attention has been paid to denormalizing tobacco sales. However, some localities have placed limits on the number and type of retailers who may sell tobacco, and some retailers have abandoned tobacco sales voluntarily. Understanding community norms surrounding tobacco sales may help accelerate tobacco denormalization. We conducted 15 focus groups with customers of California, New York, and Ohio retailers who had voluntarily discontinued tobacco sales to examine normative assumptions about where cigarettes should or should not be sold, voluntary decisions to discontinue tobacco sales, and government limits on such sales. Groups in all three states generally agreed that grocery stores that sold healthy products should not sell tobacco; California groups saw pharmacies similarly, while this was a minority opinion in the other two states. Convenience stores were regarded as a natural place to sell tobacco. In each state, it was regarded as normal and commendable for some stores to want to stop selling tobacco, although few participants could imagine convenience stores doing so. Views on government's role in setting limits on tobacco sales varied, with California and New York participants generally expressing support for restrictions, and Ohio participants expressing opposition. However, even those who expressed opposition did not approve of tobacco sales in all possible venues. Banning tobacco sales entirely was not yet normative. Limiting the ubiquitous availability of tobacco sales is key to ending the tobacco epidemic. Some limits on tobacco sales appear to be normative from the perspective of community members; it may be possible to shift norms further by problematizing the ubiquitous presence of cigarettes and drawing connections to other products already subject to restrictions.

  10. Predicting Maximum Lake Depth from Surrounding Topography

    Science.gov (United States)

    Lake volume aids understanding of the physical and ecological dynamics of lakes, yet is often not readily available. The data needed to calculate lake volume (i.e. bathymetry) are usually only collected on a lake by lake basis and are difficult to obtain across broad regions. ...

  11. Edge plasma control using an LID configuration on CHS

    Energy Technology Data Exchange (ETDEWEB)

    Masuzaki, S.; Komori, A.; Morisaki, T. [National Inst. for Fusion Science, Oroshi, Toki (Japan)] [and others

    1997-07-01

    A Local Island Divertor (LID) has been proposed to enhance energy confinement through neutral particle control. For the case of the Large Helical Device (LHD), the separatrix of an m/n = 1/1 magnetic island, formed at the edge region, will be utilized as a divertor configuration. The divertor head is inserted in the island, and the island separatrix provides connection between the edge plasma region surrounding the core plasma and the back plate of the divertor head through the field lines. The particle flux and associated heat flux from the core plasma strike the back plate of the divertor head, and thus particle recycling is localized in this region. A pumping duct covers the divertor head to form a closed divertor system for efficient particle exhaust. The advantages of the LID are ease of hydrogen pumping because of the localized particle recycling and avoidance of the high heat load that would be localized on the leading edge of the divertor head. With efficient pumping, the neutral pressure in the edge plasma region will be reduced, and hence the edge plasma temperature will be higher, hopefully leading to a better core confinement region. A LID configuration experiment was done on the Compact Helical System (CHS) to confirm the effect of the LID. The typical effects of the LID configuration on the core plasma are reduction of the line averaged density to a half, and small or no reduction of the stored energy. In this contribution, the experimental results which were obtained in edge plasma control experiments with the LID configuration in the CHS are presented.

  12. Drift motions of small-scale irregularities in the high-latitude F region: An experimental comparison with plasma drift motions

    International Nuclear Information System (INIS)

    Ruohoniemi, J.M.; Greenwald, R.A.; Baker, K.B.; Villain, J.P.; McCready, M.A.

    1987-01-01

    On the evening of January 6, 1986, coordinated observations were carried out with the Johns Hopkins University Applied Physics Laboratory HF coherent scatter radar at Goose Bay, Labrador, and the SRI International incoherent scatter radar at Sondre Stromfjord, Greenland. The common field of view comprised a section of high-latitude F region ionosphere centered on the great circle plane between the radar sites. Over a 40-min period, the HF radar observed strong backscatter from small-scale (13.9 m) field-aligned irregularities. The bulk line-of-sight drift velocity of the irregularities is deduced from the backscatter data. The returns collected simultaneously with the incoherent scatter radar are processed for estimates of the mean line-of-sight ion velocity. Approximately 100 distinct comparisons are possible between the two sets of velocity estimates. Reversals exceeding 1,000 m/s are present in both. In this paper, the authors demonstrate a correspondence between the measured irregularity and ion drifts that is consistent with the supposition that the motion of the irregularities is dominated by convective drift of the ambient plasma. This indicates that the small-scale irregularities detected by HF radars in the high-latitude F region can serve as tracers of ionospheric convective drift

  13. Bulk plasma properties in the pulsed glow discharge

    International Nuclear Information System (INIS)

    Jackson, Glen P.; King, Fred L.

    2003-01-01

    This work focuses on the spatial and temporal characteristics of a glow discharge plasma operated with power pulses of 5 ms in duration at 25% duty cycle. Interpretation of emission data provides insight into the nature of the plasma at each instant of a typical pulse cycle and at each position in space. Because the bulk plasma properties affect the distribution of excited energy levels of the sputtered atoms, an improved understanding of the plasma affords the ability to select conditions that enhance analytically important emission lines. Optical emission spectroscopy was used to determine the relative populations of excited states for atoms and ions during the initial breakdown, the steady state and the recombining periods of the discharge pulse cycle. The plasma is highly ionizing in nature at the time of breakdown--with lower excited states being overpopulated--before reaching the steady state, or plateau, period, also ionizing in nature. These behaviors arise from a loss of charged particles and photons to the surroundings that shifts the plasma away from Saha and Boltzmann balances during these periods. The post-pulse period typically displays recombining behavior, characterized by population inversion for selected species--except for regions close to the cathode, where electrons and ions are lost by diffusion and are not available for recombination. The sputtered analyte atom emissions closely mimic those of the plasma bath gas, except that their emissions persevere for longer in the recombining after-peak period than do the discharge gas species

  14. Visualization of intermittent blobby plasma transport in attached and detached plasmas of the NAGDIS-II

    International Nuclear Information System (INIS)

    Ohno, Noriyasu; Furuta, Katsuhiro; Takamura, Shuichi

    2004-01-01

    We investigated the intermittent convective plasma transport in a attached and/or detached plasma condition of the linear divertor plasma simulator, NAGDIS-II. Images taken by a fast-imaging camera clearly show that in attached plasmas, blobs are peeled off the bulk plasma, and propagate outward with an azimuthal motion. In detached plasmas, plasma turbulence observed near the plasma recombining region drives strong intermittent radial plasma transport, which could broaden the radial density profile. (author)

  15. Seasonal variation of low-latitude E-region plasma irregularities studied using Gadanki radar and ionosonde

    Directory of Open Access Journals (Sweden)

    D. V. Phanikumar

    2008-07-01

    Full Text Available In this paper, we present seasonal variation of E region field-aligned irregularities (FAIs observed using the Gadanki radar and compare them with the seasonal variation of Es observed from a nearby location SHAR. During daytime, FAIs occur maximum in summer and throughout the day, as compared to other seasons. During nighttime, FAIs occur equally in both summer and winter, and relatively less in equinoxes. Seasonal variations of Es (i.e. ftEs and fbEs show that the daytime activity is maximum in summer and the nighttime activity is maximum in equinoxes. No relation is found between FAIs occurrence/SNR and ftEs/fbEs. FAIs occurrence, however, is found to be related well with (ftEs−fbEs. This aspect is discussed in the light of the present understanding of the mid-latitude Es-FAIs relationship. The seasonal variations of FAIs observed at Gadanki are compared in detail with those of Piura, which show a significant difference in the daytime observations. The observed difference has been discussed considering the factors governing the generation of FAIs.

  16. Seasonal variation of low-latitude E-region plasma irregularities studied using Gadanki radar and ionosonde

    Directory of Open Access Journals (Sweden)

    D. V. Phanikumar

    2008-07-01

    Full Text Available In this paper, we present seasonal variation of E region field-aligned irregularities (FAIs observed using the Gadanki radar and compare them with the seasonal variation of Es observed from a nearby location SHAR. During daytime, FAIs occur maximum in summer and throughout the day, as compared to other seasons. During nighttime, FAIs occur equally in both summer and winter, and relatively less in equinoxes. Seasonal variations of Es (i.e. ftEs and fbEs show that the daytime activity is maximum in summer and the nighttime activity is maximum in equinoxes. No relation is found between FAIs occurrence/SNR and ftEs/fbEs. FAIs occurrence, however, is found to be related well with (ftEs−fbEs. This aspect is discussed in the light of the present understanding of the mid-latitude Es-FAIs relationship. The seasonal variations of FAIs observed at Gadanki are compared in detail with those of Piura, which show a significant difference in the daytime observations. The observed difference has been discussed considering the factors governing the generation of FAIs.

  17. Impacts of Artificial Reefs on Surrounding Ecosystems

    Science.gov (United States)

    Manoukian, Sarine

    Artificial reefs are becoming a popular biological and management component in shallow water environments characterized by soft seabed, representing both important marine habitats and tools to manage coastal fisheries and resources. An artificial reef in the marine environment acts as an open system with exchange of material and energy, altering the physical and biological characteristics of the surrounding area. Reef stability will depend on the balance of scour, settlement, and burial resulting from ocean conditions over time. Because of the unstable nature of sediments, they require a detailed and systematic investigation. Acoustic systems like high-frequency multibeam sonar are efficient tools in monitoring the environmental evolution around artificial reefs, whereas water turbidity can limit visual dive and ROV inspections. A high-frequency multibeam echo sounder offers the potential of detecting fine-scale distribution of reef units, providing an unprecedented level of resolution, coverage, and spatial definition. How do artificial reefs change over time in relation to the coastal processes? How accurately does multibeam technology map different typologies of artificial modules of known size and shape? How do artificial reefs affect fish school behavior? What are the limitations of multibeam technology for investigating fish school distribution as well as spatial and temporal changes? This study addresses the above questions and presents results of a new approach for artificial reef seafloor mapping over time, based upon an integrated analysis of multibeam swath bathymetry data and geoscientific information (backscatter data analysis, SCUBA observations, physical oceanographic data, and previous findings on the geology and sedimentation processes, integrated with unpublished data) from Senigallia artificial reef, northwestern Adriatic Sea (Italy) and St. Petersburg Beach Reef, west-central Florida continental shelf. A new approach for observation of fish

  18. Tomography images of the Alpine roots and surrounding upper mantle

    Science.gov (United States)

    Plomerova, Jaroslava; Babuska, Vladislav

    2017-04-01

    Teleseismic body-wave tomography represents powerful tool to study regional velocity structure of the upper mantle and to image velocity anomalies, such as subducted lithosphere plates in collisional zones. In this contribution, we recapitulate 3D models of the upper mantle beneath the Alps, which developed at a collision zone of the Eurasian and African plates. Seismic tomography studies indicate a leading role of the rigid mantle lithosphere that functioned as a major stress guide during the plate collisions. Interactions of the European lithosphere with several micro-plates in the south resulted in an arcuate shape of this mountain range on the surface and in a complicated geometry of the Alpine subductions in the mantle. Early models with one bended lithosphere root have been replaced with more advanced models showing two separate lithosphere roots beneath the Western and Eastern Alps (Babuska et al., Tectonophysics 1990; Lippitsch et al., JGR 2003). The standard isotropic velocity tomography, based on pre-AlpArray data (the currently performed passive seismic experiment in the Alps and surroundings) images the south-eastward dipping curved slab of the Eurasian lithosphere in the Western Alps. On the contrary, beneath the Eastern Alps the results indicate a very steep northward dipping root that resulted from the collision of the European plate with the Adriatic microplate. Dando et al. (2011) interpret high-velocity heterogeneities at the bottom of their regional tomographic model as a graveyard of old subducted lithospheres. High density of stations, large amount of rays and dense ray-coverage of the volume studied are not the only essential pre-requisites for reliable tomography results. A compromise between the amount of pre-processed data and the high-quality of the tomography input (travel-time residuals) is of the high importance as well. For the first time, the existence of two separate roots beneath the Alps has been revealed from carefully pre

  19. Plasma Physics An Introduction to Laboratory, Space, and Fusion Plasmas

    CERN Document Server

    Piel, Alexander

    2010-01-01

    Plasma Physics gives a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The new fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a brief introduction to plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple and emphasizes the underlying concepts. T...

  20. In Situ Observation of Hard Surrounding Rock Displacement at 2400-m-Deep Tunnels

    Science.gov (United States)

    Feng, Xia-Ting; Yao, Zhi-Bin; Li, Shao-Jun; Wu, Shi-Yong; Yang, Cheng-Xiang; Guo, Hao-Sen; Zhong, Shan

    2018-03-01

    This paper presents the results of in situ investigation of the internal displacement of hard surrounding rock masses within deep tunnels at China's Jinping Underground Laboratory Phase II. The displacement evolution of the surrounding rock during the entire excavation processes was monitored continuously using pre-installed continuous-recording multi-point extensometers. The evolution of excavation-damaged zones and fractures in rock masses were also observed using acoustic velocity testing and digital borehole cameras, respectively. The results show four kinds of displacement behaviours of the hard surrounding rock masses during the excavation process. The displacement in the inner region of the surrounding rock was found to be greater than that of the rock masses near the tunnel's side walls in some excavation stages. This leads to a multi-modal distribution characteristic of internal displacement for hard surrounding rock masses within deep tunnels. A further analysis of the evolution information on the damages and fractures inside the surrounding rock masses reveals the effects of excavation disturbances and local geological conditions. This recognition can be used as the reference for excavation and supporting design and stability evaluations of hard-rock tunnels under high-stress conditions.

  1. Field simulation of axisymmetric plasma screw pinches by alternating-direction-implicit methods

    International Nuclear Information System (INIS)

    Lambert, M.A.

    1996-06-01

    An axisymmetric plasma screw pinch is an axisymmetric column of ionized gaseous plasma radially confined by forces from axial and azimuthal currents driven in the plasma and its surroundings. This dissertation is a contribution to detailed, high resolution computer simulation of dynamic plasma screw pinches in 2-d rz-coordinates. The simulation algorithm combines electron fluid and particle-in-cell (PIC) ion models to represent the plasma in a hybrid fashion. The plasma is assumed to be quasineutral; along with the Darwin approximation to the Maxwell equations, this implies application of Ampere's law without displacement current. Electron inertia is assumed negligible so that advective terms in the electron momentum equation are ignored. Electrons and ions have separate scalar temperatures, and a scalar plasma electrical resistivity is assumed. Altemating-direction-implicit (ADI) methods are used to advance the electron fluid drift velocity and the magnetic fields in the simulation. The ADI methods allow time steps larger than allowed by explicit methods. Spatial regions where vacuum field equations have validity are determined by a cutoff density that invokes the quasineutral vacuum Maxwell equations (Darwin approximation). In this dissertation, the algorithm was first checked against ideal MM stability theory, and agreement was nicely demonstrated. However, such agreement is not a new contribution to the research field. Contributions to the research field include new treatments of the fields in vacuum regions of the pinch simulation. The new treatments predict a level of magnetohydrodynamic turbulence near the bulk plasma surface that is higher than predicted by other methods

  2. Tidal propagation in the Gulf of Khambhat, Bombay High, and surrounding areas

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Shetye, S.R.; Michael, G.S.

    -diurnal and diurnal constituents at forty-two ports in the Gulf and surrounding areas is sued to define characteristics of the tides. A barotropic numerical model based on shallow water wave equations to simulate the sea level and circulation in the region is used...

  3. Simulation of dust voids in complex plasmas

    Science.gov (United States)

    Goedheer, W. J.; Land, V.

    2008-12-01

    In dusty radio-frequency (RF) discharges under micro-gravity conditions often a void is observed, a dust free region in the discharge center. This void is generated by the drag of the positive ions pulled out of the discharge by the electric field. We have developed a hydrodynamic model for dusty RF discharges in argon to study the behaviour of the void and the interaction between the dust and the plasma background. The model is based on a recently developed theory for the ion drag force and the charging of the dust. With this model, we studied the plasma inside the void and obtained an understanding of the way it is sustained by heat generated in the surrounding dust cloud. When this heating mechanism is suppressed by lowering the RF power, the plasma density inside the void decreases, even below the level where the void collapses, as was recently shown in experiments on board the International Space Station. In this paper we present results of simulations of this collapse. At reduced power levels the collapsed central cloud behaves as an electronegative plasma with corresponding low time-averaged electric fields. This enables the creation of relatively homogeneous Yukawa balls, containing more than 100 000 particles. On earth, thermophoresis can be used to balance gravity and obtain similar dust distributions.

  4. New Measure of the Dissipation Region in Collisionless Magnetic Reconnection

    International Nuclear Information System (INIS)

    Zenitani, Seiji; Hesse, Michael; Klimas, Alex; Kuznetsova, Masha

    2011-01-01

    A new measure to identify a small-scale dissipation region in collisionless magnetic reconnection is proposed. The energy transfer from the electromagnetic field to plasmas in the electron's rest frame is formulated as a Lorentz-invariant scalar quantity. The measure is tested by two-dimensional particle-in-cell simulations in typical configurations: symmetric and asymmetric reconnection, with and without the guide field. The innermost region surrounding the reconnection site is accurately located in all cases. We further discuss implications for nonideal MHD dissipation.

  5. New Measure of the Dissipation Region in Collisionless Magnetic Reconnection

    Science.gov (United States)

    Zenitani, Seiji; Hesse, Michael; Klimas, Alex; Kuznetsova, Masha

    2012-01-01

    A new measure to identify a small-scale dissipation region in collisionless magnetic reconnection is proposed. The energy transfer from the electromagnetic field to plasmas in the electron s rest frame is formulated as a Lorentz-invariant scalar quantity. The measure is tested by two-dimensional particle-in-cell simulations in typical configurations: symmetric and asymmetric reconnection, with and without the guide field. The innermost region surrounding the reconnection site is accurately located in all cases. We further discuss implications for nonideal MHD dissipation.

  6. White paper on dusty plasmas

    International Nuclear Information System (INIS)

    Whipple, E.C.

    1986-04-01

    Dusty plasmas is the name given to plasmas heavily laden with charged dust grains which together with the surrounding ions and electrons constitute a kind of plasma regime. This field of study is receiving increased attention because of the observation of dust during recent spacecraft missions to the planets and comets, together with the dawning recognition that the evolution of dusty plasma clouds in space may be quite different from that of nondusty clouds. Recent work in this field is reviewed and recommendations are made on the kind of research that is needed in the immediate future

  7. The 14-3-3 protein interacts directly with the C-terminal region of the plant plasma membrane H(+)-ATPase

    DEFF Research Database (Denmark)

    Jahn, T.; Fuglsang, A.T.; Olsson, A.

    1997-01-01

    Accumulating evidence suggests that 14-3-3 proteins are involved in the regulation of plant plasma membrane H(+)-ATPase activity. However, it is not known whether the 14-3-3 protein interacts directly or indirectly with the H(+)-ATPase. In this study, detergent-solubilized plasma membrane H...... plasma membrane H(+)-ATPase. We propose that the 14-3-3 protein is a natural ligand of the plasma membrane H(+)-ATPase, regulating proton pumping by displacing the C-terminal autoinhibitory domain of the H(+)-ATPase....

  8. Heavy duty plasma spray gun

    International Nuclear Information System (INIS)

    Irons, G.C.; Klein, J.F.; Lander, R.D.; Thompson, H.C.; Trapani, R.D.

    1984-01-01

    A heavy duty plasma spray gun for extended industrial service is disclosed. The gun includes a gas distribution member made of a material having a coefficient of expansion different from that of the parts surrounding it. The gas distribution member is forcibly urged by a resilient member such as a coiled spring against a seal so as to assure the plasma gas is introduced into the gun arc in a manner only defined by the gas distribution member. The gun has liquid cooling for the nozzle (anode) and the cathode. Double seals are provided between the coolant and the arc region and a vent is provided between the seals which provides an indication when a seal has failed. Some parts of the gun are electrically isolated from others by an intermediate member which is formed as a sandwich of two rigid metal face pieces and an insulator disposed between them. The metal face pieces provide a rigid body to attach the remaining parts in proper alignment therewith

  9. Plasma physics an introduction to laboratory, space, and fusion plasmas

    CERN Document Server

    Piel, Alexander

    2017-01-01

    The enlarged new edition of this textbook provides a comprehensive introduction to the basic processes in plasmas and demonstrates that the same fundamental concepts describe cold gas-discharge plasmas, space plasmas, and hot fusion plasmas. Starting from particle drifts in magnetic fields, the principles of magnetic confinement fusion are explained and compared with laser fusion. Collective processes are discussed in terms of plasma waves and instabilities. The concepts of plasma description by magnetohydrodynamics, kinetic theory, and particle simulation are stepwise introduced. Space charge effects in sheath regions, double layers and plasma diodes are given the necessary attention. The novel fundamental mechanisms of dusty plasmas are explored and integrated into the framework of conventional plasmas. The book concludes with a concise description of modern plasma discharges. Written by an internationally renowned researcher in experimental plasma physics, the text keeps the mathematical apparatus simple a...

  10. HIV behavioural surveillance among refugees and surrounding host ...

    African Journals Online (AJOL)

    We used a standardised behavioural surveillance survey (BSS), modified to be directly relevant to populations in conflict and post-conflict settings as well as to their surrounding host populations, to survey the populations of a refugee settlement in south-western Uganda and its surrounding area. Two-stage probability ...

  11. Investigation of the readout electronics of DELPHI surround muon chamber

    International Nuclear Information System (INIS)

    Khovanskij, N.; Krumshtejn, Z.; Ol'shevskij, A.; Sadovskij, A.; Sedykh, Yu.; Molnar, J.; Sicho, P.; Tomsa, Z.

    1995-01-01

    The characteristics of the readout electronics of the DELPHI surround muon chambers with various AMPLEX chips (AMPLEX 16 and AMPLEX-SICAL) are presented. This electronics is studied in a cosmic rays test of the real surround muon chamber model. 4 refs., 6 figs., 1 tab

  12. Morphological Segregation in the Surroundings of Cosmic Voids

    Energy Technology Data Exchange (ETDEWEB)

    Ricciardelli, Elena; Tamone, Amelie [Laboratoire d’Astrophysique, École Polytechnique Fédérale de Lausanne (EPFL), 1290 Sauverny (Switzerland); Cava, Antonio [Observatoire de Genève, Université de Genève, 51 Ch. des Maillettes, 1290 Versoix (Switzerland); Varela, Jesus, E-mail: elena.ricciardelli@epfl.ch [Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Plaza San Juan 1, E-44001 Teruel (Spain)

    2017-09-01

    We explore the morphology of galaxies living in the proximity of cosmic voids, using a sample of voids identified in the Sloan Digital Sky Survey Data Release 7. At all stellar masses, void galaxies exhibit morphologies of a later type than galaxies in a control sample, which represent galaxies in an average density environment. We interpret this trend as a pure environmental effect, independent of the mass bias, due to a slower galaxy build-up in the rarefied regions of voids. We confirm previous findings about a clear segregation in galaxy morphology, with galaxies of a later type being found at smaller void-centric distances with respect to the early-type galaxies. We also show, for the first time, that the radius of the void has an impact on the evolutionary history of the galaxies that live within it or in its surroundings. In fact, an enhanced fraction of late-type galaxies is found in the proximity of voids larger than the median void radius. Likewise, an excess of early-type galaxies is observed within or around voids of a smaller size. A significant difference in galaxy properties in voids of different sizes is observed up to 2 R {sub void}, which we define as the region of influence of voids. The significance of this difference is greater than 3 σ for all the volume-complete samples considered here. The fraction of star-forming galaxies shows the same behavior as the late-type galaxies, but no significant difference in stellar mass is observed in the proximity of voids of different sizes.

  13. Surrounding land cover types as predictors of palustrine wetland vegetation quality in conterminous USA

    Science.gov (United States)

    Stapanian, Martin A.; Gara, Brian; Schumacher, William

    2018-01-01

    The loss of wetland habitats and their often-unique biological communities is a major environmental concern. We examined vegetation data obtained from 380 wetlands sampled in a statistical survey of wetlands in the USA. Our goal was to identify which surrounding land cover types best predict two indices of vegetation quality in wetlands at the regional scale. We considered palustrine wetlands in four regions (Coastal Plains, North Central East, Interior Plains, and West) in which the dominant vegetation was emergent, forested, or scrub-shrub. For each wetland, we calculated weighted proportions of eight land cover types surrounding the area in which vegetation was assessed, in four zones radiating from the edge of the assessment area to 2 km. Using Akaike's Information Criterion, we determined the best 1-, 2- and 3-predictor models of the two indices, using the weighted proportions of the land cover types as potential predictors. Mean values of the two indices were generally higher in the North Central East and Coastal Plains than the other regions for forested and emergent wetlands. In nearly all cases, the best predictors of the indices were not the dominant surrounding land cover types. Overall, proportions of forest (positive effect) and agriculture (negative effect) surrounding the assessment area were the best predictors of the two indices. One or both of these variables were included as predictors in 65 of the 72 models supported by the data. Wetlands surrounding the assessment area had a positive effect on the indices, and ranked third (33%) among the predictors included in supported models. Development had a negative effect on the indices and was included in only 28% of supported models. These results can be used to develop regional management plans for wetlands, such as creating forest buffers around wetlands, or to conserve zones between wetlands to increase habitat connectivity.

  14. Stimulus size dependence of hue changes induced by chromatic surrounds.

    Science.gov (United States)

    Kellner, Christian Johannes; Wachtler, Thomas

    2016-03-01

    A chromatic surround induces a change in the perceived hue of a stimulus. This shift in hue depends on the chromatic difference between the stimulus and the surround. We investigated how chromatic induction varies with stimulus size and whether the size dependence depends on the surround hue. Subjects performed asymmetric matching of color stimuli with different sizes in surrounds of different chromaticities. Generally, induced hue shifts decreased with increasing stimulus size. This decrease was quantitatively different for different surround hues. However, when size effects were normalized to an overall induction strength, the chromatic specificity was largely reduced. The separability of inducer chromaticity and stimulus size suggests that these effects are mediated by different neural mechanisms.

  15. Plasma polarization spectroscopy

    International Nuclear Information System (INIS)

    Iwamae, Atsushi; Horimoto, Yasuhiro; Fujimoto, Takashi; Hasegawa, Noboru; Sukegawa, Kouta; Kawachi, Tetsuya

    2005-01-01

    The electron velocity distribution function (EVDF) in plasma can be anisotropic in laser-produced plasmas. We have developed a new technique to evaluate the polarization degree of the emission lines in the extreme vacuum ultra violet wavelength region. The polarization of the emission lines and the continuums from the lithium-like nitrogen and from helium- and hydrogen-like carbon in recombining plasma is evaluated. Particle simulation in the velocity space gives the time scale for relaxation of anisotropic EVDFs. (author)

  16. Solar system plasma waves

    Science.gov (United States)

    Gurnett, Donald A.

    1995-01-01

    An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

  17. Consistent and robust determination of border ownership based on asymmetric surrounding contrast.

    Science.gov (United States)

    Sakai, Ko; Nishimura, Haruka; Shimizu, Ryohei; Kondo, Keiichi

    2012-09-01

    Determination of the figure region in an image is a fundamental step toward surface construction, shape coding, and object representation. Localized, asymmetric surround modulation, reported neurophysiologically in early-to-intermediate-level visual areas, has been proposed as a mechanism for figure-ground segregation. We investigated, computationally, whether such surround modulation is capable of yielding consistent and robust determination of figure side for various stimuli. Our surround modulation model showed a surprisingly high consistency among pseudorandom block stimuli, with greater consistency for stimuli that yielded higher accuracy of, and shorter reaction times in, human perception. Our analyses revealed that the localized, asymmetric organization of surrounds is crucial in the detection of the contrast imbalance that leads to the determination of the direction of figure with respect to the border. The model also exhibited robustness for gray-scaled natural images, with a mean correct rate of 67%, which was similar to that of figure-side determination in human perception through a small window and of machine-vision algorithms based on local processing. These results suggest a crucial role of surround modulation in the local processing of figure-ground segregation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Hybrid Model of Inhomogeneous Solar Wind Plasma Heating by Alfven Wave Spectrum: Parametric Studies

    Science.gov (United States)

    Ofman, L.

    2010-01-01

    Observations of the solar wind plasma at 0.3 AU and beyond show that a turbulent spectrum of magnetic fluctuations is present. Remote sensing observations of the corona indicate that heavy ions are hotter than protons and their temperature is anisotropic (T(sub perpindicular / T(sub parallel) >> 1). We study the heating and the acceleration of multi-ion plasma in the solar wind by a turbulent spectrum of Alfvenic fluctuations using a 2-D hybrid numerical model. In the hybrid model the protons and heavy ions are treated kinetically as particles, while the electrons are included as neutralizing background fluid. This is the first two-dimensional hybrid parametric study of the solar wind plasma that includes an input turbulent wave spectrum guided by observation with inhomogeneous background density. We also investigate the effects of He++ ion beams in the inhomogeneous background plasma density on the heating of the solar wind plasma. The 2-D hybrid model treats parallel and oblique waves, together with cross-field inhomogeneity, self-consistently. We investigate the parametric dependence of the perpendicular heating, and the temperature anisotropy in the H+-He++ solar wind plasma. It was found that the scaling of the magnetic fluctuations power spectrum steepens in the higher-density regions, and the heating is channeled to these regions from the surrounding lower-density plasma due to wave refraction. The model parameters are applicable to the expected solar wind conditions at about 10 solar radii.

  19. ECR Plasma Photos

    International Nuclear Information System (INIS)

    Racz, R.; Biri, S.; Palinkas, J.

    2009-01-01

    Complete text of publication follows. In order to observe and study systematically the plasma of electron cyclotron resonance (ECR) ion sources (ECRIS) we made a high number of high-resolution visible light plasma photos and movies in the ATOMKI ECRIS Laboratory. This required building the ECR ion source into an open plasma device, temporarily. An 8MP digital camera was used to record photos of plasmas made from He, methane, N, O, Ne, Ar, Kr, Xe gases and from their mixtures. The effects of the main external setting parameters (gas pressure, gas composition, magnetic field, microwave power, microwave frequency) were studied to the shape, color and structure of the plasma. The double frequency mode (9+14 GHz) was also realized and photos of this special 'star-in-star' shape plasma were recorded. A study was performed to analyze and understand the color of the ECR plasmas. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas. To our best knowledge our work is the first systematic study of ECR plasmas in the visible light region. When looking in the plasma chamber of an ECRIS we can see an axial image of the plasma (figure 1) in conformity with experimental setup. Most of the quantitative information was obtained through the summarised values of the Analogue Digital Unit (ADU) of pixels. By decreasing the strength of the magnetic trap we clearly observed that the brightness of the central part of the plasma gradually decreases, i.e. the plasma becomes more and more 'empty'. Figure 2 shows a photo series of ECR plasma at decreasing axial magnetic field. The radial size of the plasma increased because of the ascendant resonant zone. By increasing the power of the injected microwave an optimum (or at least saturation) was found in the brightness of the plasma. We found correlation between the gas dosing rates and plasma intensities. When sweeping the frequency of the microwave in a wide region

  20. Introduction to Plasma Spectroscopy

    CERN Document Server

    Kunze, H-J

    2009-01-01

    Based on lectures given at the Ruhr-University of Bochum for graduate students and postgraduates starting in plasma physics as well as from low- to high-density hot plasmas, this book introduces basic ideas and fundamental concepts and typical instrumentation from the X-ray to the infrared spectral regions

  1. Microwave plasma mode conversion

    International Nuclear Information System (INIS)

    Torres, H.S.; Sakanaka, P.H.; Villarroel, C.H.

    1985-01-01

    The behavior of hot electrons during the process of laser-produced plasma is studied. The basic equations of mode conversion from electromagnetic waves to electrostatic waves are presented. It is shown by mode conversion, that, the resonant absorption and parametric instabilities appear simultaneously, but in different plasma regions. (M.C.K.) [pt

  2. High frequency electric field spikes formed by electron beam-plasma interaction in plasma density gradients

    International Nuclear Information System (INIS)

    Gunell, H.; Loefgren, T.

    1997-02-01

    In the electron beam-plasma interaction at an electric double layer the beam density is much higher than in the classical beam-plasma experiments. The wave propagation takes place along the density gradient, that is present at the high potential side of the double layer. Such a case is studied experimentally by injecting the electron beam from a plane cathode, without any grids suppressing the gradient, and by particle simulations. The high frequency field concentrates in a sharp 'spike' with a half width of the order of one wavelength. The spike is found to be a standing wave surrounded by regions dominated by propagating waves. It forms at a position where its frequency is close to the local plasma frequency. The spike forms also when the electric field is well below the threshold for modulational instability, and long before a density cavity is formed in the simulations. Particle simulations reveal that, at the spike, there is a backward travelling wave that, when it is strongly damped, accelerates electrons back towards the cathode. In a simulation of a homogeneous plasma without the density gradient no spike is seen, and the wave is purely travelling instead of standing. 9 refs

  3. Electric field spikes formed by electron beam endash plasma interaction in plasma density gradients

    International Nuclear Information System (INIS)

    Gunell, H.; Loefgren, T.

    1997-01-01

    In the electron beam endash plasma interaction at an electric double layer the beam density is much higher than in the classical beam endash plasma experiments. The wave propagation takes place along the density gradient that is present at the high potential side of the double layer. Such a case is studied experimentally by injecting the electron beam from a plane cathode, without any grids suppressing the gradient, and by particle simulations. The high frequency field concentrates in a sharp open-quotes spikeclose quotes with a half width of the order of one wavelength. The spike is found to be a standing wave surrounded by regions dominated by propagating waves. It forms at a position where its frequency is close to the local plasma frequency. The spike forms also when the electric field is well below the threshold for modulational instability, and long before a density cavity is formed in the simulations. Particle simulations reveal that, at the spike, there is a backward traveling wave that, when it is strongly damped, accelerates electrons back towards the cathode. In a simulation of a homogeneous plasma without the density gradient no spike is seen, and the wave is purely travelling instead of standing. copyright 1997 American Institute of Physics

  4. Plasma stream transport method (2) Use of charge exchange plasma source

    International Nuclear Information System (INIS)

    Tsuchimoto, T.

    1978-01-01

    The plasma stream transport method using a single plasma source has limitations for practical film deposition. Using a charge exchange phenomenon, a new plasma source is devised and tested by the plasma stream transport machine. Metals, silicon dioxide, and nitride films are deposited by this system. The mechanism of deposition under relatively high vacuum surrounding a silicon wafer is discussed as is the effect of radical atoms

  5. Changes in unique hues induced by chromatic surrounds.

    Science.gov (United States)

    Klauke, Susanne; Wachtler, Thomas

    2016-03-01

    A chromatic surround can have a strong influence on the perceived hue of a stimulus. We investigated whether chromatic induction has similar effects on the perception of colors that appear pure and unmixed (unique red, green, blue, and yellow) as on other colors. Subjects performed unique hue settings of stimuli in isoluminant surrounds of different chromaticities. Compared with the settings in a neutral gray surround, unique hue settings altered systematically with chromatic surrounds. The amount of induced hue shift depended on the difference between stimulus and surround hues, and was similar for unique hue settings as for settings of nonunique hues. Intraindividual variability in unique hue settings was roughly twice as high as for settings obtained in asymmetric matching experiments, which may reflect the presence of a reference stimulus in the matching task. Variabilities were also larger with chromatic surrounds than with neutral gray surrounds, for both unique hue settings and matching of nonunique hues. The results suggest that the neural representations underlying unique hue percepts are influenced by the same neural processing mechanisms as the percepts of other colors.

  6. Preparation of dental amalgam and spectral diagnosis of mercury in plasmas-laser in the region of 250 nm – 850 nm

    International Nuclear Information System (INIS)

    Ossa, A De la; Pacheco, P; Sarmiento, R

    2013-01-01

    In this paper we presents results of the spectral study of plasmas-laser of dental amalgam by technique Laser-induced Breakdown Spectroscopy (LIBS). Plasmas were generated focusing the beam of a Nd: YAG laser on the matrix of the mixture Ag-Sn-Cu and on amalgams with different proportions of mercury (3:2, 5:2, 6:2). Based on the spectral results and reported atomic parameters, became estimation of electron temperature plasmas- laser and their behavior with the concentration of Hg. The estimated values of the electron temperature for the respective proportions were 20 846 K, 19 139 K and 16 872 K, using the distribution of population of Boltzmann energy levels associated with spectral lines, considering conditions Local Thermodinamic Equilibrium (LTE) of plasmas

  7. Echo phenomena in a plasma

    International Nuclear Information System (INIS)

    Pavlenko, V.N.

    1983-01-01

    The mechanism of echo phenomenon in different plasma media: laboratory and cosmic plasma, metals and semiconductors is analyzed to get a more comprehensive idea on collective processes in a plasma and for practical applications in radiophysics and plasma diagnostics. The echo phenomenon permitted to confirm a reversible nature of the Landau damping, to prove the fact that the information on perturbation is conserved in a plasma (as non-damping oscillations of the distribution function) even after disappearing of the macroscopic field. The dependence of the diffusion coefficient on the velocity is measured, microturbulences in a plasma are investigated. New ways of the plasma wave conversion are suggested, as well as ''lightning'' of super-critical plasma layers and regions of plasma non-transparency. Prospective advantages of using echo for studying the mechanisms of charged particle interaction with the surface bounding a plasma are revealed

  8. Dust in flowing magnetized plasma

    International Nuclear Information System (INIS)

    Pandey, Birendra P.; Samarian, Alex A.; Vladimirov, Sergey V.

    2009-01-01

    Plasma flows occur in almost every laboratory device and interactions of flowing plasmas with near-wall impurities and/or dust significantly affects the efficiency and lifetime of such devices. The charged dust inside the magnetized flowing plasma moves primarily under the influence of the plasma drag and electric forces. Here, the charge on the dust, plasma potential, and plasma density are calculated self-consistently. The electrons are assumed non-Boltzmannian and the effect of electron magnetization and electron-atom collisions on the dust charge is calculated in a self-consistent fashion. For various plasma magnetization parameters viz. the ratio of the electron and ion cyclotron frequencies to their respective collision frequencies, plasma-atom and ionization frequencies, the evolution of the plasma potential and density in the flow region is investigated. The variation of the dust charge profile is shown to be a sensitive function of plasma parameters. (author)

  9. Mercury's plasma belt: hybrid simulations results compared to in-situ measurements

    Science.gov (United States)

    Hercik, D.; Travnicek, P. M.; Schriver, D.; Hellinger, P.

    2012-12-01

    The presence of plasma belt and trapped particles region in the Mercury's inner magnetosphere has been questionable due to small dimensions of the magnetosphere of Mercury compared to Earth, where these regions are formed. Numerical simulations of the solar wind interaction with Mercury's magnetic field suggested that such a structure could be found also in the vicinity of Mercury. These results has been recently confirmed also by MESSENGER observations. Here we present more detailed analysis of the plasma belt structure and quasi-trapped particle population characteristics and behaviour under different orientations of the interplanetary magnetic field.The plasma belt region is constantly supplied with solar wind protons via magnetospheric flanks and tail current sheet region. Protons inside the plasma belt region are quasi-trapped in the magnetic field of Mercury and perform westward drift along the planet. This region is well separated by a magnetic shell and has higher average temperatures and lower bulk proton current densities than surrounding area. On the day side the population exhibits loss cone distribution function matching the theoretical loss cone angle. Simulations results are also compared to in-situ measurements acquired by MESSENGER MAG and FIPS instruments.

  10. Dynacore Final Report , Plasma Physics prototype

    NARCIS (Netherlands)

    Lourens, W.

    2000-01-01

    The generation and behaviour of plasma in a fusion device and its interaction with sur-rounding materials is studied by observing several phenomena that will accompany a plasma discharge. These phenomena are recorded by means of so called Diagnostics. These are instruments that comprise complex

  11. The plasma universe

    International Nuclear Information System (INIS)

    Faelthammar, C.G.

    1989-12-01

    The term 'Plasma Universe', coined by Hannes Alfven, emphasices the fact that plasma phenomena discovered in the laboratory and in accessible regions of space. must be important also in the rest of the universe, which consists almost entirely of matter in the plasma state. Relevant aspect of this concept will be discussed. They include the response of the plasma to electric currents, the support of magnetic-field aligned electric fields, violation of the frozen-field condition, rapid release of magnetically stored energy, acceleration of charged particles, chemical separation, and filamentary and cellular structures. (authors)

  12. A synchronous surround increases the motion strength gain of motion.

    Science.gov (United States)

    Linares, Daniel; Nishida, Shin'ya

    2013-11-12

    Coherent motion detection is greatly enhanced by the synchronous presentation of a static surround (Linares, Motoyoshi, & Nishida, 2012). To further understand this contextual enhancement, here we measured the sensitivity to discriminate motion strength for several pedestal strengths with and without a surround. We found that the surround improved discrimination of low and medium motion strengths, but did not improve or even impaired discrimination of high motion strengths. We used motion strength discriminability to estimate the perceptual response function assuming additive noise and found that the surround increased the motion strength gain, rather than the response gain. Given that eye and body movements continuously introduce transients in the retinal image, it is possible that this strength gain occurs in natural vision.

  13. Surrounding Moving Obstacle Detection for Autonomous Driving Using Stereo Vision

    Directory of Open Access Journals (Sweden)

    Hao Sun

    2013-06-01

    Full Text Available Detection and tracking surrounding moving obstacles such as vehicles and pedestrians are crucial for the safety of mobile robotics and autonomous vehicles. This is especially the case in urban driving scenarios. This paper presents a novel framework for surrounding moving obstacles detection using binocular stereo vision. The contributions of our work are threefold. Firstly, a multiview feature matching scheme is presented for simultaneous stereo correspondence and motion correspondence searching. Secondly, the multiview geometry constraint derived from the relative camera positions in pairs of consecutive stereo views is exploited for surrounding moving obstacles detection. Thirdly, an adaptive particle filter is proposed for tracking of multiple moving obstacles in surrounding areas. Experimental results from real-world driving sequences demonstrate the effectiveness and robustness of the proposed framework.

  14. Contamination of nebulisers and surrounding air at the bedside of ...

    African Journals Online (AJOL)

    An air sampler was used to collect air samples from the surrounding bedside environment. .... individualised resealable plastic bags and stored upside down in a cooler .... conventional and mesh technology nebulisers used at home by adults.

  15. Glow phenomenon surrounding the vertical stabilizer and OMS pods

    Science.gov (United States)

    1994-01-01

    This 35mm frame, photographed as the Space Shuttle Columbia was orbiting Earth during a 'night' pass, documents the glow phenomenon surrounding the vertical stabilizer and the Orbital Maneuvering System (OMS) pods of the spacecraft.

  16. Plasma Brightenings in a Failed Solar Filament Eruption

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.; Ding, M. D., E-mail: yingli@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210023 (China)

    2017-03-20

    Failed filament eruptions are solar eruptions that are not associated with coronal mass ejections. In a failed filament eruption, the filament materials usually show some ascending and falling motions as well as generating bright EUV emissions. Here we report a failed filament eruption (SOL2016-07-22) that occurred in a quiet-Sun region observed by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory . In this event, the filament spreads out but gets confined by the surrounding magnetic field. When interacting with the ambient magnetic field, the filament material brightens up and flows along the magnetic field lines through the corona to the chromosphere. We find that some materials slide down along the lifting magnetic structure containing the filament and impact the chromosphere, and through kinetic energy dissipation, cause two ribbon-like brightenings in a wide temperature range. There is evidence suggesting that magnetic reconnection occurs between the filament magnetic structure and the surrounding magnetic fields where filament plasma is heated to coronal temperatures. In addition, thread-like brightenings show up on top of the erupting magnetic fields at low temperatures, which might be produced by an energy imbalance from a fast drop of radiative cooling due to plasma rarefaction. Thus, this single event of a failed filament eruption shows the existence of a variety of plasma brightenings that may be caused by completely different heating mechanisms.

  17. Simulations and observations of plasma depletion, ion composition, and airglow emissions in two auroral ionospheric depletion experiments

    International Nuclear Information System (INIS)

    Yau, A.W.; Whalen, B.A.; Harris, F.R.; Gattinger, R.L.; Pongratz, M.B.; Bernhardt, P.A.

    1985-01-01

    In an ionospheric depletion experiment where chemically reactive vapors such as H 2 O and CO 2 are injected into the O + dominant F region to accelerate the plasma recombination rate and to reduce the plasma density, the ion composition in the depleted region is modified, and photometric emissions are produced. We compare in situ ion composition, density, and photometric measurements from two ionospheric depletion experiments with predictions from chemical modeling. The two injections, Waterhole I and III, were part of an auroral perturbation experiment and occurred in different ambient conditions. In both injections a core region of greater than fivefold plasma depletion was observed over roughly-equal5-km diameter within seconds of the injection, surrounded by an outer region of less drastic and slower depletion. In Waterhole I the plasma density was depleted tenfold over a 30-km diamter region after 2 min. The ambient O + density was drastically reduced, and the molecular O + 2 abundance was enhanced fivehold in the depletion region. OH airglow emission associated with the depletion was observed with a peak emission intensity of roughly-equal1 kR. In Waterhole III the ambient density was a decade lower, and the plasma depletion was less drastic, being twofold over 30 km after 2 min. The airglow emissions were also much less intense and below measurement sensitivity (30 R for the OH 306.4-nm emission; 50 R for the 630.0-nm emission)

  18. Monitoring program of surrounding of the NPP SE-EBO

    International Nuclear Information System (INIS)

    Dobis, L.; Kostial, J.

    1997-01-01

    The paper dealt with monitoring program of radiation control of surrounding of the NPP Bohunice, which has the aim: (1) to ensure the control of influence of work of the NPP Bohunice on the environment in their surrounding; (2) to ensure the back-ground for regular brief of control and supervisory organs about condition of the environment in surrounding of the NPP Bohunice; (3) to maintain the expected technical level of control of the NPP Bohunice and to exploit optimally the technical means; (4) to solicit permanently the data about the radioactivity of environment in surrounding of the NPP Bohunice for forming of files of the data; (5) to exploit purposefully the technical equipment, technical workers and to maintain their in permanent emergency and technical eligibility for the case of the breakdown; (6) to obtain permanently the files of the values for qualification of the reference levels. This program of monitoring includes the radiation control of surrounding of the NPP Bohunice, in the time of normal work of power-station's blocks, inclusively of all types of trouble-shooting and repairer works in surrounding of the NPP Bohunice, up to distance 20 km from power-station. The monitoring includes: outlets from the NPP Bohunice, monitoring of radiation characteristics in surrounding of the NPP Bohunice, (aerosols, fall-outs, soil), the links of food chains: (grass and fodder, milk, agriculture products), hydrosphere in surrounding (surface waters, drink water, bores of radiation control in complex of the NPP Bohunice, components of the hydrosphere), measurement of radiation from external sources (measurement of the dose rates, measurement of the doses [sk

  19. Chromatic induction from surrounding stimuli under perceptual suppression.

    Science.gov (United States)

    Horiuchi, Koji; Kuriki, Ichiro; Tokunaga, Rumi; Matsumiya, Kazumichi; Shioiri, Satoshi

    2014-11-01

    The appearance of colors can be affected by their spatiotemporal context. The shift in color appearance according to the surrounding colors is called color induction or chromatic induction; in particular, the shift in opponent color of the surround is called chromatic contrast. To investigate whether chromatic induction occurs even when the chromatic surround is imperceptible, we measured chromatic induction during interocular suppression. A multicolor or uniform color field was presented as the surround stimulus, and a colored continuous flash suppression (CFS) stimulus was presented to the dominant eye of each subject. The subjects were asked to report the appearance of the test field only when the stationary surround stimulus is invisible by interocular suppression with CFS. The resulting shifts in color appearance due to chromatic induction were significant even under the conditions of interocular suppression for all surround stimuli. The magnitude of chromatic induction differed with the surround conditions, and this difference was preserved regardless of the viewing conditions. The chromatic induction effect was reduced by CFS, in proportion to the magnitude of chromatic induction under natural (i.e., no-CFS) viewing conditions. According to an analysis with linear model fitting, we revealed the presence of at least two kinds of subprocesses for chromatic induction that reside at higher and lower levels than the site of interocular suppression. One mechanism yields different degrees of chromatic induction based on the complexity of the surround, which is unaffected by interocular suppression, while the other mechanism changes its output with interocular suppression acting as a gain control. Our results imply that the total chromatic induction effect is achieved via a linear summation of outputs from mechanisms that reside at different levels of visual processing.

  20. Plasma and current structures in dynamical pinches

    International Nuclear Information System (INIS)

    Butov, I.Ya.; Matveev, Yu.V.

    1981-01-01

    Dynamics of plasma layers and current structure in aZ-pinch device has been experimentally investigated. It is found that shaping of a main current envelope is ended with its explosion-like expansion, the pinch decaying after compression to separated current filaments. It is also shown that filling of a region outside the pinch with plasma and currents alternating in directions occurs owing to interaction of current loops (inductions) formed in a magnetic piston during its compression with reflected shock wave. Current circulating in the loops sometimes exceeds 1.5-2 times the current of discharge circuit. The phenomena noted appear during development of superheat instability and can be realized, for example, in theta-pinches, plasma focuses, tokamaks. The experiments were carried out at the Dynamic Zeta-pinch device at an energy reserse of up to 15 kJ (V 0 =24 kV) in a capacitor bank. Half-period of the discharge current is 9 μs; Isub(max)=3.5x10sup(5) A. Back current guide surrounding a china chamber of 28 cm diameter and 50 cm length is made in the form of a hollow cylinder. Initial chamber vacuum is 10 -6 torr [ru

  1. Plasma turbulence

    International Nuclear Information System (INIS)

    Horton, W.

    1998-07-01

    The origin of plasma turbulence from currents and spatial gradients in plasmas is described and shown to lead to the dominant transport mechanism in many plasma regimes. A wide variety of turbulent transport mechanism exists in plasmas. In this survey the authors summarize some of the universally observed plasma transport rates

  2. Plasma-based radar cross section reduction

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generatio...

  3. Optical plasma torch electron bunch generation in plasma wakefield accelerators

    Directory of Open Access Journals (Sweden)

    G. Wittig

    2015-08-01

    Full Text Available A novel, flexible method of witness electron bunch generation in plasma wakefield accelerators is described. A quasistationary plasma region is ignited by a focused laser pulse prior to the arrival of the plasma wave. This localized, shapeable optical plasma torch causes a strong distortion of the plasma blowout during passage of the electron driver bunch, leading to collective alteration of plasma electron trajectories and to controlled injection. This optically steered injection is more flexible and faster when compared to hydrodynamically controlled gas density transition injection methods.

  4. On the stability of localized drift modes in the boundary layers of high density gas insulated plasmas

    International Nuclear Information System (INIS)

    Ohlsson, D.

    1977-11-01

    Gas blanket systems are of interest for mainly two reasons. First, plasma wall interaction effects are expected to be considerably reduced due to the presence of the surrounding neutral gas. Consequently the impurity radiation due to impurities originating from plasma wall interaction processes is probably eliminated to a large extent. Second, the fueling of a future thermonuclear reactor can take place in a natural way in gas blanket systems in the sense that neutrals can diffuse inwards at a suitable rate to replace burnt fuel under certain conditions. In this analysis we consider certain stability aspects of plasmas surrounded by neutral gas. In particular we consider the stability of localized collisional drift modes, in the cool partially ionized boundary regions. In these regions large pressure gradients are expected due to plasma neutral gas interaction effects. It is concluded that stability is possible within certain parameter ranges due to the presence of several stabilizing effects associated with finite Larmor radius and viscosity effects and coupling between dissipative effects directly or indirectly connected with plasma neutral gas interaction processes

  5. Forest Fragments Surrounded by Sugar Cane Are More Inhospitable to Terrestrial Amphibian Abundance Than Fragments Surrounded by Pasture

    Directory of Open Access Journals (Sweden)

    Paula Eveline Ribeiro D’Anunciação

    2013-01-01

    Full Text Available In recent years, there has been increasing interest in matrix-type influence on forest fragments. Terrestrial amphibians are good bioindicators for this kind of research because of low vagility and high philopatry. This study compared richness, abundance, and species composition of terrestrial amphibians through pitfall traps in two sets of semideciduous seasonal forest fragments in southeastern Brazil, according to the predominant surrounding matrix (sugar cane and pasture. There were no differences in richness, but fragments surrounded by sugar cane had the lowest abundance of amphibians, whereas fragments surrounded by pastures had greater abundance. The most abundant species, Rhinella ornata, showed no biometric differences between fragment groups but like many other amphibians sampled showed very low numbers of individuals in fragments dominated by sugar cane fields. Our data indicate that the sugar cane matrix negatively influences the community of amphibians present in fragments surrounded by this type of land use.

  6. Plasma properties

    International Nuclear Information System (INIS)

    Weitzner, H.

    1990-06-01

    This paper discusses the following topics: MHD plasma activity: equilibrium, stability and transport; statistical analysis; transport studies; edge physics studies; wave propagation analysis; basic plasma physics and fluid dynamics; space plasma; and numerical methods

  7. Dynacore Final Report , Plasma Physics prototype

    OpenAIRE

    Lourens, W.

    2000-01-01

    The generation and behaviour of plasma in a fusion device and its interaction with sur-rounding materials is studied by observing several phenomena that will accompany a plasma discharge. These phenomena are recorded by means of so called Diagnostics. These are instruments that comprise complex electronic equipment, coupled to various sensors. The generation of the plasma is also governed by electronic systems that control different parameters of the fusion device, the Tokamak, and of auxilia...

  8. Plasma accelerators

    International Nuclear Information System (INIS)

    Bingham, R.; Angelis, U. de; Johnston, T.W.

    1991-01-01

    Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating gradients. Starting with the plasma beat wave accelerator (PBWA) and laser wakefield accelerator (LWFA) schemes and the plasma wakefield accelerator (PWFA) steady progress has been made in theory, simulations and experiments. Computations are presented for the study of LWFA. (author)

  9. Presheath profiles in simulated tokamak edge plasmas

    International Nuclear Information System (INIS)

    LaBombard, B.; Conn, R.W.; Hirooka, Y.; Lehmer, R.; Leung, W.K.; Nygren, R.E.; Ra, Y.; Tynan, G.

    1988-04-01

    The PISCES plasma surface interaction facility at UCLA generates plasmas with characteristics similar to those found in the edge plasmas of tokamaks. Steady state magnetized plasmas produced by this device are used to study plasma-wall interaction phenomena which are relevant to tokamak devices. We report here progress on some detailed investigations of the presheath region that extends from a wall surface into these /open quotes/simulated tokamak/close quotes/ edge plasma discharges along magnetic field lines

  10. Active but inoperable thrombin is accumulated in a plasma protein layer surrounding Streptococcus pyogenes

    NARCIS (Netherlands)

    Naudin, Clément; Hurley, Sinead M.; Malmström, Erik; Plug, Tom; Shannon, Oonagh; Meijers, Joost C. M.; Mörgelin, Matthias; Björck, Lars; Herwald, Heiko

    2015-01-01

    Activation of thrombin is a critical determinant in many physiological and pathological processes including haemostasis and inflammation. Under physiological conditions many of these functions are involved in wound healing or eradication of an invading pathogen. However, when activated systemically,

  11. Communication and surrounding of Asco and Vandellos II nuclear power plants

    International Nuclear Information System (INIS)

    2004-01-01

    The Asco and Vandellos-II power plants have always been integrated into the regions where they are located, and they take an active part in the development of surrounding towns through quality employment provided by our facilities, social and cultural support and aid to development promoted by regional councils. Communication to media is a corporate priority defined in our strategic plant, to ensure openness, rigour and punctuality. We also attend to the visitors who want to learn more about our facilities in the visitor center, and we have agreements with agrarian institutions in the area so that students can de practical training in the farms we own for agricultural production. (Author)

  12. Involvement of high plasma corticosterone status and activation of brain regional serotonin metabolism in long-term erythrosine-induced rearing motor hyper activity in young adult male rats.

    Science.gov (United States)

    Dalal, Arindam; Poddar, Mrinal K

    2010-07-01

    Long-term consumption of artificial food color(s) can induce behavioral hyperactivity in human and experimental animals, but no neurobiochemical mechanism is defined. This study investigates the role of brain regional serotonin metabolism including its turnover, MAO-A activity, and plasma corticosterone status in relation to behavioral disturbances due to an artificial food color, erythrosine. Long-term (15 or 30 consecutive days) erythrosine administration with higher dosage (10 or 100 mg/kg/day, p.o.) produced optimal hyperactive state in exploratory behavior (rearing motor activity) after 2 h of last erythrosine administration, in young adult male albino rats. Erythrosine-induced stimulation in brain regional (medulla-pons, hypothalamus, hippocampus, and corpus striatum) serotonin metabolism (measuring steady state levels of 5-HT and 5-HIAA, MAO-A activity), including its turnover (pargyline-induced 5-HT accumulation and 5-HIAA declination rate), as well as plasma corticosterone were also observed depending on dosage(s) and duration(s) of erythrosine administration under similar experimental conditions. The lower dosage of erythrosine (1 mg/kg/day, p.o.) under similar conditions did not affect either of the above. These findings suggests (a) the induction as well as optimal effect of long-term erythrosine (artificial food color) on behavioral hyperactivity in parallel with increase in 5-HT level in brain regions, (b) the activation of brain regional serotonin biosynthesis in accordance with plasma corticosterone status under such behavioral hyperactivity, and (c) a possible inhibitory influence of the enhanced glucocorticoids-serotonin interaction on erythrosine-induced rearing motor hyperactivity in young adult mammals.

  13. Assessment of land degradation and its spatial and temporal variation in Beijing surrounding area

    Science.gov (United States)

    Li, Shuang; Dong, Suocheng; Zhang, Xiaojun; Zhiqiang, Gao

    2005-08-01

    The indulgence in willful persecution of sandstorm had made great attention of many countries around the world. Chinese government and the Chinese academy of science going with some other countries have devoted a large amount of vigor to study the crucial environment problem. Due to the main source areas of sandstorm all located in the arid and semi-arid regions where there have great area, hard natural condition and bad traffic condition, it's very difficult to accomplish source area and the reason of sandstorm. For this destination, a international cooperation organization has been established to clarify the occur mechanism, transfer process and the following environment impact of sandstorm. The organization includes many researchers come form USA, Japan, Korea, and so on. Beijing surrounding area is one of the main sandstorm sources in recent years. In order to understand fully of the sandstorm form and development, we analyzed the land use degradation of Beijing surrounding area during the last ten years. 71 scenes Landsat TM/ETM, 611 scenes DRG and DEM data had been processed in our study. This paper made a detail describe of using Landsat image data and high resolution DEM data to construe the soil erosion and vegetation degenerate. The result shows that the irrational human activities and land use style are the main factors of land use degradation. In case of Beijing surrounding area, the land degradation directly impacted the frequency and intensity of sand & dust storm in Northern China. The case study region of Beijing surrounding area includes 51 counties that belong to three provinces and autonomous regions.

  14. Investigation into the behavior of metal-argon polyatomic ions (MAr+) in the extraction region of inductively coupled plasma-mass spectrometry

    International Nuclear Information System (INIS)

    Ebert, Chris H.; Witte, Travis M.; Houk, R.S.

    2012-01-01

    The abundances of metal-argon polyatomic ions (MAr + ) are determined in inductively coupled plasma-mass spectrometry (ICP-MS). The ratios of MAr + abundance to that for M + ions are measured experimentally. These ratios are compared to expected values, calculated for typical plasma conditions using spectroscopic data. For all metals studied (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn), the measured ratios are significantly lower than the calculated ratios. Increasing the plasma potential (and thereby increasing the ion kinetic energy) by means of a homemade guard electrode with a wide gap further reduces the MAr + /M + ratio. Implementing a skimmer cone designed for high transmission of light ions increases the MAr + abundance. Considering this evidence, the scarcity of MAr + ions is attributed to collision induced dissociation (CID), likely due to a shock wave at the tip of or in the throat of the skimmer cone. - Highlights: ► MAr + ions are less abundant in the mass spectrum than expected from the ICP. ► Increasing the plasma potential reduces their abundance further. ► The extraction lens voltage does not greatly affect the MAr + abundances. ► The weakly-bound MAr + ions are probably dissociated by collisions during extraction.

  15. Placental vascular responses are dependent on surrounding tissue

    DEFF Research Database (Denmark)

    Brøgger, Torbjørn Halle

    -depth understanding of the mechanism regulating blood flow and perfusion is necessary if we are to come up with new ideas for intervention and treatment. Method: From fresh born placentas stem villi arteries were carefully dissected. The artery branches were divided. The surrounding tissue was removed from one end...... and was left untouched in the other end. Then using wire myography they were investigated in terms of contractility and sensitivity to physiological relevant human-like agonists. Results: Sensitivity to PGF2α, Tx-analog, 5-HT and endothelin-1 was significantly lower in arteries with intact surrounding tissue...... compared to arteries stripped of the tissue. The maximal force development was also significantly lower in arteries with surrounding tissue, when they were depolarized high extracellular [K+] or stimulated with PGF2α or endotheline-1. Conclusion: The perivascular tissue significantly alters stem villi...

  16. Placental vascular responses are dependent on surrounding tissue

    DEFF Research Database (Denmark)

    Brøgger, Torbjørn Halle

    . Materials and methods. From fresh born placentas, stem villi arteries were carefully dissected. The artery branches were divided. The surrounding tissue was removed from one end and was left untouched in the other end.Then, using wire myography, they were investigated in terms of contractility...... and sensitivity to physiological relevant human-like agonists. Results. Sensitivity to PGF2α, Tx-analog, 5-HT and endothelin-1 was significantly lower in arteries with intact surrounding tissue compared to arteries stripped of the tissue. The maximal force development was also significantly lower in arteries...... with surrounding tissue when they were depolarized high extracellular [K+] or stimulated with PGF2α or endotheline-1. Conclusion. The perivascular tissue significantly alters stem villi arteries' sensitivity and force development in a suppressive way. This implicates a new aspect of blood flow regulation...

  17. Second regional plasmapheresis conference and workshop for Southeast Asia (SEA) on the immunomodulatory role of plasma exchange in central and peripheral nervous system disorders, Kuala Lumpur, Malaysia, 9th December 2017.

    Science.gov (United States)

    Viswanathan, Shanthi; Hung, Stefanie Kar Yan; Goyal, Vinay; Apiwattanakul, Metha; Thirugnanam, Umapathi N; Abdullah, Suhailah; Aye, Seinn Mya Mya; Ohnmar, Ohnmar; Si, Le Tri; Keosodsay, Saysavath; Estiasari, Riwanti; Khalife, Najib; Hiew, Fu Liong

    2018-04-06

    In December 2017, 79 delegates attended the 2nd regional plasmapheresis conference and workshop for Southeast Asia (SEA) on the immunomodulatory role of plasma exchange in central and peripheral nervous system disorders in Kuala Lumpur, Malaysia. This meeting featured 6 plenary lectures, interactive sessions dedicated for experience sharing, case presentations, and a practical session for paramedics. Clinical experts and researchers from 7 SEA countries and India shared experience and challenges in treating autoimmune neurological disorders. While the spectrum of diseases and neurology practice remained largely similar, there was great disparities in accessibility of therapeutic plasma exchange (TPE) within SEA countries and between urban or rural settings. Costs, human resources, and healthcare policies are common challenges in providing sustainable TPE services. Novel techniques and innovative ideas in performing TPE were explored. A working consortium comprising of key opinion leaders was proposed to improve standards of TPE and enhance future research. © 2018 Wiley Periodicals, Inc.

  18. Mini-cavity plasma core reactors for dual-mode space nuclear power/propulsion systems

    International Nuclear Information System (INIS)

    Chow, S.

    1976-01-01

    A mini-cavity plasma core reactor is investigated for potential use in a dual-mode space power and propulsion system. In the propulsive mode, hydrogen propellant is injected radially inward through the reactor solid regions and into the cavity. The propellant is heated by both solid driver fuel elements surrounding the cavity and uranium plasma before it is exhausted out the nozzle. The propellant only removes a fraction of the driver power, the remainder is transferred by a coolant fluid to a power conversion system, which incorporates a radiator for heat rejection. In the power generation mode, the plasma and propellant flows are shut off, and the driver elements supply thermal power to the power conversion system, which generates electricity for primary electric propulsion purposes

  19. On the macroscopic oscillation and deformation of the plasma in SPICA

    International Nuclear Information System (INIS)

    Mimura, M.; Kooijman, W.; Oomens, A.A.M.

    1976-10-01

    By using a set of pick-up coils positioned around the minor circumference of the discharge tube, the stability behaviour of the screw-pinch plasma in SPICA is studied. The data-processing system, AD-converters combined with a conputer, enables us to treat a large number of signals. The signals from the pick-up coils are transferred to the computer and are expanded into a Fourier series. The m = 1 cosine oscillation in the rise phase suggests a screw-pinch model in which a plasma core is surrounded by a current layer and a vacuum region. An m = 2 deformation is found to correlate with the decay rate of the plasma current

  20. Interaction of a laser-breakdown plasma with a charged metallic target

    International Nuclear Information System (INIS)

    Vasil'ev, B.I.; Grasyuk, A.Z.; Dyad'kin, A.P.; Sukhanov, A.N.

    1981-01-01

    A study was made of the influence of a laser plasma on the potential of an insulated conducting target. It was discovered that the target potential changed stepwise on illumination with a high-power TEA CO 2 laser. A step, ΔU, in the target potential was observed and the dependences of ΔU on the initial potential, laser radiation energy density, and geometrical dimensions of the illuminated region were determined. There was an optimal pressure of the surrounding air for which ΔU had the maximum value. The dependence of ΔU on the pressure was determined, when illuminating a target in air and in nitrogen. The temporal characteristics of the variation in ΔU were correlated with the time variation of the visible and ultraviolet luminescence from the plasma. A mechanism was proposed to explain the potential step accompanying the interaction of a laser-produced plasma with a charged metallic target

  1. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A method is described for electron beam heating of a high-density plasma to drive a fast liner. An annular or solid relativistic electron beam is used to heat a plasma to kilovolt temperatures through streaming instabilities in the plasma. Energy deposited in the plasma then converges on a fast liner to explosively or ablatively drive the liner to implosion. (U.K.)

  2. Plasma Modes

    Science.gov (United States)

    Dubin, D. H. E.

    This chapter explores several aspects of the linear electrostatic normal modes of oscillation for a single-species non-neutral plasma in a Penning trap. Linearized fluid equations of motion are developed, assuming the plasma is cold but collisionless, which allow derivation of the cold plasma dielectric tensor and the electrostatic wave equation. Upper hybrid and magnetized plasma waves in an infinite uniform plasma are described. The effect of the plasma surface in a bounded plasma system is considered, and the properties of surface plasma waves are characterized. The normal modes of a cylindrical plasma column are discussed, and finally, modes of spheroidal plasmas, and finite temperature effects on the modes, are briefly described.

  3. Magnetosheath jets: MMS observations of internal structures and jet interactions with ambient plasma

    Science.gov (United States)

    Plaschke, F.; Karlsson, T.; Hietala, H.; Archer, M. O.; Voros, Z.; Nakamura, R.; Magnes, W.; Baumjohann, W.; Torbert, R. B.; Russell, C. T.; Giles, B. L.

    2017-12-01

    The dayside magnetosheath downstream of the quasi-parallel bow shock is commonly permeated by high-speed jets. Under low IMF cone angle conditions, large scale jets alone (with cross-sectional diameters of over 2 Earth radii) have been found to impact the subsolar magnetopause once every 6 minutes - smaller scale jets occurring much more frequently. The consequences of jet impacts on the magnetopause can be significant: they may trigger local reconnection and waves, alter radiation belt electron drift paths, disturb the geomagnetic field, and potentially generate diffuse throat aurora at the dayside ionosphere. Although some basic statistical properties of jets are well-established, their internal structure and interactions with the surrounding magnetosheath plasma are rather unknown. We present Magnetospheric Multiscale (MMS) observations which reveal a rich jet-internal structure of high-amplitude plasma moment and magnetic field variations and associated currents. These variations/structures are generally found to be in thermal and magnetic pressure balance; they mostly (but not always) convect with the plasma flow. Small velocity differences between plasma and structures are revealed via four-spacecraft timing analysis. Inside a jet core region, where the plasma velocity maximizes, structures are found to propagate forward (i.e., with the jet), whereas backward propagation is found outside that core region. Although super-magnetosonic flows are detected by MMS in the spacecraft frame of reference, no fast shock is seen as the jet plasma is sub-magnetosonic with respect to the ambient magnetosheath plasma. Instead, the fast jet plasma pushes ambient magnetosheath plasma ahead of the jet out of the way, possibly generating anomalous sunward flows in the vicinity, and modifies the magnetic field aligning it with the direction of jet propagation.

  4. Analysis of the geomorphology surrounding the Chang'e-3 landing site

    International Nuclear Information System (INIS)

    Li Chun-Lai; Mu Ling-Li; Zou Xiao-Duan; Liu Jian-Jun; Ren Xin; Zeng Xing-Guo; Yang Yi-Man; Zhang Zhou-Bin; Liu Yu-Xuan; Zuo Wei; Li Han

    2014-01-01

    Chang'e-3 (CE-3) landed on the Mare Imbrium basin in the east part of Sinus Iridum (19.51°W, 44.12°N), which was China's first soft landing on the Moon and it started collecting data on the lunar surface environment. To better understand the environment of this region, this paper utilizes the available high-resolution topography data, image data and geological data to carry out a detailed analysis and research on the area surrounding the landing site (Sinus Iridum and 45 km×70 km of the landing area) as well as on the topography, landform, geology and lunar dust of the area surrounding the landing site. A general topographic analysis of the surrounding area is based on a digital elevation model and digital elevation model data acquired by Chang'e-2 that have high resolution; the geology analysis is based on lunar geological data published by USGS; the study on topographic factors and distribution of craters and rocks in the surrounding area covering 4 km×4 km or even smaller is based on images from the CE-3 landing camera and images from the topographic camera; an analysis is done of the effect of the CE-3 engine plume on the lunar surface by comparing images before and after the landing using data from the landing camera. A comprehensive analysis of the results shows that the landing site and its surrounding area are identified as typical lunar mare with flat topography. They are suitable for maneuvers by the rover, and are rich in geological phenomena and scientific targets, making it an ideal site for exploration

  5. Analysis of the geomorphology surrounding the Chang'e-3 landing site

    Science.gov (United States)

    Li, Chun-Lai; Mu, Ling-Li; Zou, Xiao-Duan; Liu, Jian-Jun; Ren, Xin; Zeng, Xing-Guo; Yang, Yi-Man; Zhang, Zhou-Bin; Liu, Yu-Xuan; Zuo, Wei; Li, Han

    2014-12-01

    Chang'e-3 (CE-3) landed on the Mare Imbrium basin in the east part of Sinus Iridum (19.51°W, 44.12°N), which was China's first soft landing on the Moon and it started collecting data on the lunar surface environment. To better understand the environment of this region, this paper utilizes the available high-resolution topography data, image data and geological data to carry out a detailed analysis and research on the area surrounding the landing site (Sinus Iridum and 45 km×70 km of the landing area) as well as on the topography, landform, geology and lunar dust of the area surrounding the landing site. A general topographic analysis of the surrounding area is based on a digital elevation model and digital elevation model data acquired by Chang'e-2 that have high resolution; the geology analysis is based on lunar geological data published by USGS; the study on topographic factors and distribution of craters and rocks in the surrounding area covering 4 km×4 km or even smaller is based on images from the CE-3 landing camera and images from the topographic camera; an analysis is done of the effect of the CE-3 engine plume on the lunar surface by comparing images before and after the landing using data from the landing camera. A comprehensive analysis of the results shows that the landing site and its surrounding area are identified as typical lunar mare with flat topography. They are suitable for maneuvers by the rover, and are rich in geological phenomena and scientific targets, making it an ideal site for exploration.

  6. Fiscal 1998 achievement report on regional consortium research and development project. Venture business fostering regional consortium in its 2nd year--Creation of key industries (Development of multi-purpose high-precision plasma process); 1998 nendo tamokuteki koseido netsu plasma process no kaihatsu seika hokokusho. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Research and development is conducted of a new material process using thermal plasma for manufacturing new ceramics efficiently and for forming a high-quality spray-deposited ceramic coating high in melting point. In the development of devices, addition of an insulation convergence section enables the construction of a plasma jet generator which operates with stability across a range from atmospheric pressure through 10{sup -1} Torr and exhibits high thermal efficiency of approximately 70%. In the study of basic matters, the thermal plasma process is experimented for its optimization and the interaction between thermal plasma and injected materials is elucidated. In the development of a technology for manufacturing high-quality sprayed coatings, optimum plasma spraying conditions are established for each grain size of alumina/titania composite materials, with the rate of one component to the other taken into consideration. The optimum plasma spraying conditions are determined after examining the state of fused powder recovered after plasma spraying, porosity, the rate of coating adhesion, etc. It is found that coatings formed by high-power thermal plasma application are attributable to the vapor-solid process and, thanks to the finding, a crystal orientation control technology is developed for such coatings. (NEDO)

  7. Ornitocenosis of the Sursky pond and its close the surroundings

    International Nuclear Information System (INIS)

    Lacko, J.; Ambrus, B.; Fupso, A.

    2013-01-01

    The paper focuses on the qualitative-quantitative research of fishpond bird community of the Sursky and its surroundings as well as on analysis of seasonal population dynamics of the avifauna as well as on placing the determined species into environmental groups and guilds. Another object is the comparison of our results with recent work focused on research of bird communities on this site.

  8. Review of Ordered Anarchy: Jasay and his Surroundings

    Directory of Open Access Journals (Sweden)

    Aschwin de Wolf

    2009-02-01

    Full Text Available Anthony de Jasay is among the most important social thinkers of our time. His oeuvre offers a sustained critique of government and its defenders. In the book Ordered Anarchy: Jasay and His Surroundings, colleagues and friends pay tribute to the man in the form of an inspiring collection of essays.

  9. Neutron spectrum in small iron pile surrounded by lead reflector

    International Nuclear Information System (INIS)

    Kimura, Itsuro; Hayashi, S.A.; Kobayashi, Katsuhei; Matsumura, Tetsuo; Nishihara, Hiroshi.

    1978-01-01

    In order to save the quantity of sample material, a possibility to assess group constants of a reactor material through measurement and analysis of neutron spectrum in a small sample pile surrounded by a reflector of heavy moderator, was investigated. As the sample and the reflector, we chose iron and lead, respectively. Although the time dispersion in moderation of neutrons was considerably prolonged by the lead reflector, this hardly interferes with the assessment of group constants. Theoretical calculation revealed that both the neutron flux spectrum and the sensitivity coefficient of group constants in an iron sphere, 35 cm in diameter surrounded by the lead reflector, 25 cm thick, were close to those of the bare iron sphere, 108 cm in diameter. The neutron spectra in a small iron pile surrounded by a lead reflector were experimentally obtained by the time-of-flight method with an electron linear accelerator and the result was compared with the predicted values. It could be confirmed that a small sample pile surrounded by a reflector, such as lead, was as useful as a much larger bulk pile for the assessment of group constants of a reactor material. (auth.)

  10. Linking disadvantaged housing areas to the surrounding city

    DEFF Research Database (Denmark)

    Stender, Marie

    Several disadvantaged social housing areas in Denmark are currently undergo-ing thorough physical refurbishments, aiming to integrate them better with the surrounding city. The ambition is to attract new users and residents by opening up the borders of the area and establish attractive, new...

  11. The bird species of pandam wildlife park and the surrounding ...

    African Journals Online (AJOL)

    The effect of time of day as well as vegetation variables on bird species diversity in the park and surrounding farmlands was also conducted. 10 transects in each study site were surveyed twice between during the dry season and vegetation variables (trees, fingers, finger-rings two- hand, grazing, farming, canopy cover, ...

  12. Experiences during the decontamination process of areas surrounding to Fukushima

    International Nuclear Information System (INIS)

    Molina, G.

    2014-10-01

    In this work the experience gained during the decontamination of areas surrounding to Fukushima NPP, rugged during the earthquake and tsunami in 2011 and caused the contamination with fission products in these areas is described. Actions taken by the Japanese government are reported and some of the techniques used, the intervention levels and the progress made and disposal techniques considered are presented. (Author)

  13. Traditional Indian customs surrounding birth A review | Chalmers ...

    African Journals Online (AJOL)

    Since 1960, only a few studies have been made of traditional custOIns surrounding birth in Indian culture. Very few of these have described customs followed by Indians in South Africa. A review of these publications is presented here. Customs described include religious, social and psychological aspects of behaviour in ...

  14. Diagnostic significance of DNA and antibodies against capsid antigens of anti-Epstein–Barr virus antibodies levels in blood plasma of nasopharyngeal carcinoma patients from non-endemic region

    Directory of Open Access Journals (Sweden)

    V. E. Gurtsevich

    2015-01-01

    Full Text Available Epstein–Barr virus (EBV, a representative of the herpesvirus family, is the etiological agent for a number of benign and malignant human neoplasms. Among the latter, the nasopharyngeal carcinoma (NPC occupies a special place. In NPC development EBV plays a key role stimulating the progression of the pathological process from precancerous lesions to the cancer development. For most NPC patients, elevated levels of humoral IgG and IgA antibodies against capsid and early EBV antigens are characteristic and their antibody titers rise to high levels long before the diagnosis of cancer. Using this phenomenon, virus-specific antibodies are used for many years as markers for NPC screening, especially in cases of undiagnosed primary lesion. In recent years, in endemic for NPC regions (South China, South-East Asia a great attention has been paid to the use of quantitative determination of EBV DNA copies in the blood plasma of patients with NPC as a method of early cancer detection and monitoring.The aim of this study was to compare clinical significance of EBV DNA and humoral antibodies levels in blood plasma of NPC patients in non-endemic region, Russia. The results obtained indicate that both markers DNA / EBV and IgA antibodies against capsid EBV antigens can be successfully used for diagnosis of NPC in non-endemic region. However, in comparison with the virus-specific antibody titers, the viral DNA levels in the patients plasma are more sensitive and specific as NPC marker reflecting the efficacy of the therapy, and the state of remission or relapse.

  15. Observation of plasma hole in a rotating plasma

    International Nuclear Information System (INIS)

    Nagaoka, Kenichi; Ishihara, Tatsuzo; Okamoto, Atsushi; Yoshimura, Shinji; Tanaka, Masayoshi Y.

    2001-01-01

    Plasma hole, a cylindrical density cavity, formed in a rotating plasma has been investigated experimentally. The plasma hole is characterized by large aspect ratio (length/radius ≥ 30), steep boundary layer between the hole and the ambient plasma (10 ion Larmor radius), and extremely high positive potential (130 V). The flow velocity field associated with plasma hole structure has been measured, and is found to have interesting features: (1) plasma rotates in azimuthal direction at a maximum velocity of order of ion sound speed, (2) plasma flows radially inward across the magnetic field line, (3) there present an axial flow reversal between core and peripheral region. It is found that the flow pattern of the plasma hole is very similar to the that of well-developed typhoon with core. (author)

  16. Linear antenna microwave plasma CVD diamond deposition at the edge of no-growth region of C-H-O ternary diagram

    Czech Academy of Sciences Publication Activity Database

    Potocký, Štěpán; Babchenko, Oleg; Hruška, Karel; Kromka, Alexander

    2012-01-01

    Roč. 249, č. 12 (2012), s. 2612-2615 ISSN 0370-1972 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA ČR GAP205/12/0908 Institutional research plan: CEZ:AV0Z10100521 Keywords : C-H-O phase diagram * nanocrystalline diamond * plasma enhanced CVD * Raman spectroscopy * SEM Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.489, year: 2012

  17. Research on plasma core reactors

    International Nuclear Information System (INIS)

    Jarvis, G.A.; Barton, D.M.; Helmick, H.H.; Bernard, W.; White, R.H.

    1977-01-01

    Experiments and theoretical studies are being conducted for NASA on critical assemblies with 1-m-diam by 1-m-long low-density cores surrounded by a thick beryllium reflector. These assemblies make extensive use of existing nuclear propulsion reactor components, facilities, and instrumentation. Due to excessive porosity in the reflector, the initial critical mass was 19 kg U(93.2). Addition of a 17-cm-thick by 89-cm-diam beryllium flux trap in the cavity reduced the critical mass to 7 kg when all the uranium was in the zone just outside the flux trap. A mockup aluminum UF 6 container was placed inside the flux trap and fueled with uranium-graphite elements. Fission distributions and reactivity worths of fuel and structural materials were measured. Finally, an 85,000-cm 3 aluminum canister in the central region was fueled with UF 6 gas and fission density distributions determined. These results will be used to guide the design of a prototype plasma core reactor which will test energy removal by optical radiation

  18. A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome

    OpenAIRE

    Moaddel, Ruin; Venkata, Swarajya Lakshmi Vattem; Tanga, Mary J.; Bupp, James E.; Green, Carol E.; Iyer, Lalitha; Furimsky, Anna; Goldberg, Michael E.; Torjman, Marc C.; Wainer, Irving W.

    2010-01-01

    A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in Complex Regional Pain Syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)-and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric ...

  19. Vasculature surrounding a nodule: A novel lung cancer biomarker.

    Science.gov (United States)

    Wang, Xiaohua; Leader, Joseph K; Wang, Renwei; Wilson, David; Herman, James; Yuan, Jian-Min; Pu, Jiantao

    2017-12-01

    To investigate whether the vessels surrounding a nodule depicted on non-contrast, low-dose computed tomography (LDCT) can discriminate benign and malignant screen detected nodules. We collected a dataset consisting of LDCT scans acquired on 100 subjects from the Pittsburgh Lung Screening study (PLuSS). Fifty subjects were diagnosed with lung cancer and 50 subjects had suspicious nodules later proven benign. For the lung cancer cases, the location of the malignant nodule in the LDCT scans was known; while for the benign cases, the largest nodule in the LDCT scan was used in the analysis. A computer algorithm was developed to identify surrounding vessels and quantify the number and volume of vessels that were connected or near the nodule. A nonparametric receiver operating characteristic (ROC) analysis was performed based on a single nodule per subject to assess the discriminability of the surrounding vessels to provide a lung cancer diagnosis. Odds ratio (OR) were computed to determine the probability of a nodule being lung cancer based on the vessel features. The areas under the ROC curves (AUCs) for vessel count and vessel volume were 0.722 (95% CI=0.616-0.811, plung cancer group 9.7 (±9.6) compared to the non-lung cancer group 4.0 (±4.3) CONCLUSION: Our preliminary results showed that malignant nodules are often surrounded by more vessels compared to benign nodules, suggesting that the surrounding vessel characteristics could serve as lung cancer biomarker for indeterminate nodules detected during LDCT lung cancer screening using only the information collected during the initial visit. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. The influence of nitrogen entrainment on argon plasmas created by the 'Torche à Injection Axiale' (TIA)

    NARCIS (Netherlands)

    Jonkers, J.; Hartgers, A.; Selen, L.J.M.; Mullen, van der J.J.A.M.; Schram, D.C.

    1999-01-01

    When a plasma is sustained in the open air, nitrogen will diffuse into the plasma. Especially for plasmas sustained by the `Torche à Injection Axiale' (TIA) this appears to be the case, since this turbulent jet draws gases from the surroundings. In the argon plasma the entrained nitrogen is probably

  1. Dynamics of magnetospheric plasmas

    International Nuclear Information System (INIS)

    Horwitz, J.L.

    1985-01-01

    The dynamical behavior of the magnetospheric plasmas which control the electrostatic charging of spacecraft is the result of the complex interaction of a variety of production, loss, transport, and energization mechanisms in the magnetosphere. This paper is intended to provide the spacecraft engineer with a foundation in the basic morphology and controlling processes pertaining to magnetospheric plasma dynamics in the inner magnetosphere, including the synchronous orbit region. 32 references

  2. High-frequency plasma oscillations

    Energy Technology Data Exchange (ETDEWEB)

    Akhiezer, A I; Fainberg, Y B; Sitenko, A G; Stepanov, K; Kurilko, V; Gorbatenko, M; Kirochkin, U [Academy of Sciences of the Ukrainian SSR (USSR)

    1958-07-01

    It is well known that the electrical conductivity of a plasma, the ion-electron equilibration time, and the time required to heat the electron component of the plasma all increase greatly with increasing temperature. Consequently, the usual method of Joule heating a plasma may be difficult to apply in the region of high temperatures (> 10{sup 6}K), especially if the plasma current alone, without any additional measures, is used to generate magnetic fields for the confinement of the plasma. Therefore, it is of interest to study methods of plasma heating that do not directly use Joule heat, especially methods by which energy is directly supplied to the ion component during the time between collisions. Some of these methods make use of ionic resonance as well as other resonance phenomena which can occur in plasma in an external magnetic field. This paper deals with certain aspects of the theory of high-frequency plasma oscillations.

  3. Report of the results of the fiscal 1997 regional consortium R and D project. Regional consortium energy field / Development of the plasma use surface treatment process by in-situ control (first fiscal year); 1997 nendo chiiki consortium kenkyu kaihatsu jigyo. Chiiki consortium energy bun`ya / in-situ seigyo ni yoru plasma riyo hyohi shori process no kaihatsu (daiichi nendo) seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The paper described the fiscal 1997 result of the development. To know of in-plasma phenomena such as carburization and nitriding, a basic plasma experimental device was fabricated for quantitative measurement of reaction activity species. For the study of reaction control between plasma and substrate, a rotary analyzer type ellipsometer was fabricated as a method to detect composition and thickness of the deposit on the substrate surface. For He gas cooling after carburization and hardening, basic specifications for He gas refining/circulating system were confirmed. For perfect non-hazardous processing of exhaust gas from plasma carburization furnace, conducted was the thermodynamic computation of the process. Priority in order of the functions to be possessed as specifications for basic design of mini plant is plasma carburization, He gas cooling, and in-situ measurement. To make the most of the plasma use surface treatment as substitutes for expensive alloy elements, sliding parts/die-cast mold raw materials were carburized to measure the hardness. The Cr carbide coating technology by plasma CVD is also under study as an application example except carburization. 47 refs., 59 figs., 31 tabs.

  4. Fiscal 1999 regional consortium R and D project. Report of R and D results on regional consortium energy (R and D of hybrid pulse plasma coating (HPPC) system - 2nd year); 1999 nendo hybrid gata pulse plasma coating (HPPC) system no kenkyu kaihatsu seika hokokusho. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    A surface reforming system was developed which enables DLC or ceramic films to be uniformly and adhesively coated on the surfaces of objects such as metallic dies and tools of complicated shape, which used to be impossible by a conventional dry coating. This paper describes the fiscal 1999 results. The technologies consist of pulse introduction of gaseous materials, pulse generation of plasma, application of negative high-voltage pulse, the HPPC (hybrid pulse plasma coating) system of advanced hybrid control, etc. Technologies were developed for 1 Hz pulse on/off introduction of methane and toluene gas, with the film forming experiment carried out. The density of Ar plasma formed by RF was measured by a Langmuir probe method. High densities of plasma were successfully achieved by a magnetic field. In the experiment of applying a negative pulse voltage to a model metallic die, it was possible to apply up to 14 kV pulse voltage. Elucidated was a plasma chemical phenomenon at the time of pulse gas introduction and pulse plasma formation, using a quadrupole mass spectrometer capable of measuring ion types in plasma, with the control conditions optimized. (NEDO)

  5. Transport barriers in plasmas

    International Nuclear Information System (INIS)

    Caldas, I L; Szezech, J D Jr; Kroetz, T; Marcus, F A; Roberto, M; Viana, R L; Lopes, S R

    2012-01-01

    We discuss the creation of transport barriers in magnetically confined plasmas with non monotonic equilibrium radial profiles. These barriers reduce the transport in the shearless region (i.e., where the twist condition does not hold). For the chaotic motion of particles in an equilibrium electric field with a nonmonotonic radial profile, perturbed by electrostatic waves, we show that a nontwist transport barrier can be created in the plasma by modifying the electric field radial profile. We also show non twist barriers in chaotic magnetic field line transport in the plasma near to the tokamak wall with resonant modes due to electric currents in external coils.

  6. Computing in plasma physics

    International Nuclear Information System (INIS)

    Nuehrenberg, J.

    1986-01-01

    These proceedings contain the articles presented at the named conference. These concern numerical methods for astrophysical plasmas, the numerical simulation of reversed-field pinch dynamics, methods for numerical simulation of ideal MHD stability of axisymmetric plasmas, calculations of the resistive internal m=1 mode in tokamaks, parallel computing and multitasking, particle simulation methods in plasma physics, 2-D Lagrangian studies of symmetry and stability of laser fusion targets, computing of rf heating and current drive in tokamaks, three-dimensional free boundary calculations using a spectral Green's function method, as well as the calculation of three-dimensional MHD equilibria with islands and stochastic regions. See hints under the relevant topics. (HSI)

  7. Regional Hippocampal Atrophy and Higher Levels of Plasma Amyloid-Beta Are Associated With Subjective Memory Complaints in Nondemented Elderly Subjects

    DEFF Research Database (Denmark)

    Cantero, Jose L; Iglesias, Juan E.; Van Leemput, Koen

    2016-01-01

    Background: Evidence suggests a link between the presence of subjective memory complaints (SMC) and lower volume of the hippocampus, one of the first regions to show neuropathological lesions in Alzheimer's disease. However, it remains unknown whether this pattern of hippocampal atrophy is region...

  8. Dynamic identification of plasma magnetic contour in fusion machines

    International Nuclear Information System (INIS)

    Bettini, P.; Trevisan, F.; Cavinato, M.

    2005-01-01

    The paper presents a method to identify the plasma magnetic contour in fusion machines, when eddy currents are present in the conducting structures surrounding the plasma. The approach presented is based on the integration of an electromagnetic model of the plasma with a lumped parameters model of the conducting structures around the plasma. This approach has been validated against experimental data from RFX, a reversed field pinch machine. (author)

  9. Plasma centrifuges

    International Nuclear Information System (INIS)

    Karchevskij, A.I.; Potanin, E.P.

    2000-01-01

    The review of the most important studies on the isotope separation processes in the rotating plasma is presented. The device is described and the characteristics of operation of the pulse plasma centrifuges with weakly and strongly ionized plasma as well as the stationary plasma centrifuges with the medium weak ionization and devices, applying the stationary vacuum arc with the high ionization rate and the stationary beam-plasma discharge with complete ionization, are presented. The possible mechanisms of the isotope separation in plasma centrifuges are considered. The specific energy consumption for isotope separation in these devices is discussed [ru

  10. Plasma astrophysics

    CERN Document Server

    Kaplan, S A; ter Haar, D

    2013-01-01

    Plasma Astrophysics is a translation from the Russian language; the topics discussed are based on lectures given by V.N. Tsytovich at several universities. The book describes the physics of the various phenomena and their mathematical formulation connected with plasma astrophysics. This book also explains the theory of the interaction of fast particles plasma, their radiation activities, as well as the plasma behavior when exposed to a very strong magnetic field. The text describes the nature of collective plasma processes and of plasma turbulence. One author explains the method of elementary

  11. Plasma waves

    CERN Document Server

    Swanson, DG

    1989-01-01

    Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th

  12. On- and off-axis spectral emission features from laser-produced gas breakdown plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Harilal, S. S.; Skrodzki, P. J.; Miloshevsky, A.; Brumfield, B. E.; Phillips, M. C.; Miloshevsky, G.

    2017-06-01

    Laser-heated gas breakdown plasmas or sparks emit profoundly in the ultraviolet and visible region of the electromagnetic spectrum with contributions from ionic, atomic, and molecular species. Laser created kernels expand into a cold ambient with high velocities during its early lifetime followed by confinement of the plasma kernel and eventually collapse. However, the plasma kernels produced during laser breakdown of gases are also capable of exciting and ionizing the surrounding ambient medium. Two mechanisms can be responsible for excitation and ionization of surrounding ambient: viz. photoexcitation and ionization by intense ultraviolet emission from the sparks produced during the early times of its creation and/or heating by strong shocks generated by the kernel during its expansion into the ambient. In this study, an investigation is made on the spectral features of on- and off-axis emission features of laser-induced plasma breakdown kernels generated in atmospheric pressure conditions with an aim to elucidate the mechanisms leading to ambient excitation and emission. Pulses from an Nd:YAG laser emitting at 1064 nm with 6 ns pulse duration are used to generate plasma kernels. Laser sparks were generated in air, argon, and helium gases to provide different physical properties of expansion dynamics and plasma chemistry considering the differences in laser absorption properties, mass density and speciation. Point shadowgraphy and time-resolved imaging were used to evaluate the shock wave and spark self-emission morphology at early and late times while space and time resolved spectroscopy is used for evaluating the emission features as well as for inferring plasma fundaments at on- and off-axis. Structure and dynamics of the plasma kernel obtained using imaging techniques are also compared to numerical simulations using computational fluid dynamics code. The emission from the kernel showed that spectral features from ions, atoms and molecules are separated in

  13. Plasma mid-regional pro-adrenomedullin levels are inversely associated with anxiety but unrelated to depression: Results from the observational DIAST-CHF study in patients with cardiovascular risk factors.

    Science.gov (United States)

    Meyer, Thomas; Herrmann-Lingen, Christoph; Chavanon, Mira-Lynn; Pieske, Burkert; Wachter, Rolf; Edelmann, Frank

    2015-12-01

    It has been postulated that patients with heart failure have a high risk of ventricular arrhythmias and sudden cardiac death resulting from anxiety-induced autonomic arousal. In the prospective and multicenter DIAST-CHF (Diagnostic Trial on Prevalence and Clinical Course of Diastolic Dysfunction and Heart Failure) study, we therefore, tested the hypothesis that adrenomedullin (ADM), a well-established predictor for cardiovascular outcome, is associated with self-rated anxiety symptoms in patients at risk of suffering from or actually with overt heart failure. Study participants with risk factors for diastolic dysfunction were requested to complete the Hospital Anxiety and Depression Scale (HADS), and plasma mid-regional pro-adrenomedullin (MR-proADM) concentrations were measured. In bivariate analysis, we found significantly lower plasma MR-proADM levels in patients with elevated HADS-anxiety scores above the clinically relevant cut-off level of ≥11 (n=118, 536pmol/l, interquartile range [IQR] 449-626) as compared to non-anxious study participants (n=1,292, 573pmol/l, IQR 486-702, p=0.001). A set of multivariate models adjusted for potential confounders confirmed the negative association between self-rated anxiety symptoms and plasma MR-proADM. In similar models, no significant association was detected between HADS-depression scores and MR-proADM. The inverse relationship between plasma MR-proADM and anxiety observed in patients with cardiovascular risk factors supports a previous experimental study using a mutant mouse line with a brain-specific loss of ADM expression which displayed hyperactive and over-anxious behavior. Further experimental and clinical studies are warranted to test the hypothesis that also in humans ADM acts as a neuromodulator with anxiolytic properties. Copyright © 2015. Published by Elsevier Ltd.

  14. Miniature Coaxial Plasma injector Diagnostics by Beam Plasma Interaction

    International Nuclear Information System (INIS)

    El-Tayeb, H.; El-Gamal, H.

    2003-01-01

    A miniature coaxial gun has been used to study the interaction between plasma beam and low density plasma formed in glow discharge. The peak discharge current flow between the coaxial electrodes was 5.25 kA as a single pulse with pulse width of 60 mu. Investigations are carried out with argon gas at pressure 0.4 Torr. The plasma stream ejected from the coaxial discharge propagates in the neutral argon atoms with mean velocity of 1.2x10 5 cm/s. The plasma stream temperature and density were 4.2 eV and 2.4x10 13 cm -3 respectively. An argon negative glow has been used as base plasma where its electron temperature and density were 2.2 eV and 6.2x10 7 cm -3 respectively. When the plasma stream propagates through the negative glow discharge region its velocity decreased to 8.8 x 10 4 cm/s and also the plasma electron temperature decreased to 3.1 eV, while the stream density remained the same. An excited wave appeared on the electric probe having frequency equal to the plasma frequency of the plasma under consideration. Simulation of the problem showed that this method could be applied for plasma diagnostics within the region of investigation. Those further studies for high temperature, dense, and magnetized plasma will be considered

  15. Replication analysis of genetic association of the NCAN-CILP2 region with plasma lipid levels and non-alcoholic fatty liver disease in Asian and Pacific ethnic groups.

    Science.gov (United States)

    Boonvisut, Supichaya; Nakayama, Kazuhiro; Makishima, Saho; Watanabe, Kazuhisa; Miyashita, Hiroshi; Lkhagvasuren, Munkhtulga; Kagawa, Yasuo; Iwamoto, Sadahiko

    2016-01-13

    The Neurocan-cartilage intermediate layer protein 2 (NCAN-CILP2) region forms a tight linkage disequilibrium (LD) block and is associated with plasma lipid levels and non-alcoholic fatty liver disease (NAFLD) in individuals of European descent but not in the Malay and Japanese ethnic groups. Recent genome-wide resequence studies identified a missense single-nucleotide polymorphism (SNP) (rs58542926) of the transmembrane 6 superfamily member 2 (TM6SF2) gene in the NCAN-CILP2 region related to hepatic triglyceride content. This study aims to analyze the influences of SNPs in this region on NAFLD and plasma lipid levels in the Asian and Pacific ethnic groups and to reveal the reasons behind positive and negative genetic associations dependent on ethnicity. Samples and characteristic data were collected from 3,013 Japanese, 119 Palauan, 947 Mongolian, 212 Thai and 401 Chinese people. Hepatic sonography data was obtained from the Japanese individuals. Genotyping data of five SNPs, rs58542926, rs735273, rs1009136, rs1858999, and rs16996148, were used to verify the effect on serum lipid levels by multiple linear regression, and the association with NAFLD in the Japanese population was examined by logistic regression analysis. rs58542926 showed significant association with the plasma triglyceride (TG) level in Japanese (P = 0.0009, effect size = 9.5 (± 3.25) mg/dl/allele) and Thai (P = 0.0008, effect size = 31.6 (± 11.7) mg/dl/allele) study subjects. In Mongolian individuals, there was a significant association of rs58542926 with total cholesterol level (P = 0.0003, 11.7 (± 3.2) mg/dl/allele) but not with TG level. In multiple comparisons in Chinese individuals, rs58542926 was weakly (P = 0.022) associated with TG levels, although the threshold for statistical significance was not reached. In Palauan individuals, there was no significant association with the studied SNPs. rs58542926 also showed significant association with Japanese NAFLD. The minor allele (t) increased

  16. Mechanical Characteristics Analysis of Surrounding Rock on Anchor Bar Reinforcement

    Science.gov (United States)

    Gu, Shuan-cheng; Zhou, Pan; Huang, Rong-bin

    2018-03-01

    Through the homogenization method, the composite of rock and anchor bar is considered as the equivalent material of continuous, homogeneous, isotropic and strength parameter enhancement, which is defined as reinforcement body. On the basis of elasticity, the composite and the reinforcement are analyzed, Based on strengthening theory of surrounding rock and displacement equivalent conditions, the expression of reinforcement body strength parameters and mechanical parameters is deduced. The example calculation shows that the theoretical results are close to the results of the Jia-mei Gao[9], however, closer to the results of FLAC3D numerical simulation, it is proved that the model and surrounding rock reinforcement body theory are reasonable. the model is easy to analyze and calculate, provides a new way for determining reasonable bolt support parameters, can also provides reference for the stability analysis of underground cavern bolting support.

  17. Plasma fractionation for blood products: isolation and purification of coagulating factors, albumin and immunoglobulin

    International Nuclear Information System (INIS)

    Siti Najila Mohd Janib; Shaharuddin Mohd; Wan Hamirul Bahrin Wan Kamal

    2005-01-01

    Approximately 12 million liters of human plasma are fractionated world-wide annually. However, with the market for clotting factors and other haemoderivatives steadily increasing from year to year, the amount processed will also increase correspondingly to keep up with the demand. In Malaysia, part of the need for the blood products are obtained commercially but a major portion of the requirement involves sending the plasma collected by the National Blood Centre to Australia for processing. Following purification and isolation of the blood products, they are sent back to Malaysia for local consumption. As yet there are no plasma fractionation plants in the South East Asia region, it would be advantageous to establish a local fractionation plant as it would be able to cater for local demands of the haemoderivatives and thus reduces the cost of importing these products. Besides, this facility will be able to provide contract fractionation services to the surrounding region. Early work in MINT has started in trying to purify plasma obtained from rats. Purification of the plasma was performed by using Sephadex G-25 column. Short term objective of this project is to develop the technique of extraction, fractionation and purification of blood products such as albumin, globulin and clotting factors (Factor VIII and Factor IX). The long term emphasis will be to scale up the production facility to a pilot plant stage and eventually to a national fractionation and purification plant. (Author)

  18. Advection of long lived density blobs in the turbulent state of a simple magnetized torus plasma

    International Nuclear Information System (INIS)

    Barni, R; Riccardi, C

    2009-01-01

    The turbulent regime of a simple magnetized toroidal plasma column has been studied in the plasma device Thorello. The detection and the study of the spatio-temporal evolution of structures have been performed by means of conditional sampling techniques as well as other statistical tools. As a result the evidence of plasma blob formation and expulsion from the edge of the main plasma column has been obtained. The relation between structure phenomenology and statistical characteristics of the turbulent regime has been investigated. The motion of the density structures in the edge region of our device does not look ballistic but rather driven by the overall potential profile established in the turbulent state. Potential fluctuations are strongly anti-correlated with density structures, located in the same position and somewhat more extended. They provide a shallow potential well with a flat bottom and quite sharp edges surrounding and co-moving with the blobs. Blob lifetime exceeds the residence time associated with the overall E x B drift field. Then such persistent structures provide a means for a net convection of the charged particles to the limiter, across the magnetic field and beyond the edge region of the plasma.

  19. Diversity of vascular plants of Piestany and surroundings (presentation)

    International Nuclear Information System (INIS)

    Penzesova, A.; Galusova, T.

    2013-01-01

    In this presentation is a summary of the results of floristic research aimed at determining diversity of vascular plants of Piestany and its surroundings. Plant taxa we determined using the designation keys. We have compiled a list of plant species occurring in the monitored area, we evaluated the selected botanical-phytogeographical characteristics of flora, we've put together a list of local protected, endangered and rare species and a list of local invasive and expansive species according to sources. (Authors)

  20. Methods of Assessing Noise Nuisance of Real Estate Surroundings

    Directory of Open Access Journals (Sweden)

    Szopińska Kinga

    2016-03-01

    Full Text Available Testing what factors create the market value of real estate is key information when preparing property valuations as well as other opinions and professional evaluations on the basis of which court verdicts or administrative decisions are made. One of the factors influencing the value of some real estate is the level of noise present in the surroundings, which can lead to the occurrence of noise nuisance negatively affecting social relations.

  1. The characteristics of cerebral meningiomas and surrounding tissues on dynamic CT

    International Nuclear Information System (INIS)

    Jinkins, J.R.; Sener, R.N.

    1991-01-01

    Dynamic CT was utilized to evaluate 11 patients with histologically benign meningiomas. While it was found that all demonstrated macroscopic neovascularity, subtle differences in the dynamic perfusion curves were identified both between different meningiomas and from region to region within the same tumor. Other than basic anatomic differences, these changes may reflect intratumoral ischemia and hypothetically herald cystic/necrotic alteration within the neoplasm. The dynamic calculations over the surrounding brain showed areas of gross hyper- and hypoperfused cerebral cortex, and hypoperfused white matter in regions of peritumoral edema. These latter findings are of uncertain clinical importance. The dynamic examination also confirmed cases of dural venous sinus invasion and calvarial permeation by tumor. In addition, the dynamic series showed macroscopic neovascularity in one case with a completely negative selective cerebral arteriogram. It is felt that certain cases which have previously been evaluated by static CT may benefit from further study utilizing the dynamic method. (orig.)

  2. EDITORIAL: 80 Years of Plasma 80 Years of Plasma

    Science.gov (United States)

    Franklin, R. N.; Braithwaite, N. St J.

    2009-02-01

    Irving Langmuir proposed the term 'plasma' in a paper in 1928 (Proc. Natl Acad. Sci. USA 14 627-637) to describe a 'region containing balanced charges of ions and electrons'. There does not appear to be any record of the thinking behind this proposal, so it is difficult to be definitive. One idea is that since the Greek word 'plasma' was used to describe a mouldable fluid, 'neon' lighting, with its almost limitless ability to provide colourful shapes, provided the inspiration. Another relates to the prior medical use in relation to blood with its variety of different 'corpuscles' and that the essential description of the positive column required one to recognize at least the role of the separate species of electrons, ions and gas atoms. Tonks, when questioned thirty years later, was inclined to the latter idea, but it is unlikely that we shall ever know for certain. (See postscript added December 2008.) Forty years ago most of the interest in terrestrial plasmas was centred on fusion and the prospect of thus solving the world's energy problems; the quest continues. However, since then a whole new industry has developed. It emerged in the 1970s as an imaginative way to remove the photoresist layers used in patterning semiconductor wafers. Slowly but steadily, plasma-based 'dry' processes began to displace the traditional wet chemistry processes of cleaning, etching and depositing by which the first generation of integrated circuits had been made. Plasma technology offered higher yields while accommodating the complexity of ever-shrinking feature size, driving the microelectronic revolution for almost four decades. Langmuir certainly ushered in an exciting branch of physics when he introduced the term plasma. We have included as Appendix I a condensed CV for Irving Langmuir to show, amongst other things, the early influences on his subsequent life. An interlude in Paris gave him a taste of the wider world of Europe. His subsequent schooling in the United States led

  3. Numerical Simulation on Zonal Disintegration in Deep Surrounding Rock Mass

    Directory of Open Access Journals (Sweden)

    Xuguang Chen

    2014-01-01

    Full Text Available Zonal disintegration have been discovered in many underground tunnels with the increasing of embedded depth. The formation mechanism of such phenomenon is difficult to explain under the framework of traditional rock mechanics, and the fractured shape and forming conditions are unclear. The numerical simulation was carried out to research the generating condition and forming process of zonal disintegration. Via comparing the results with the geomechanical model test, the zonal disintegration phenomenon was confirmed and its mechanism is revealed. It is found to be the result of circular fracture which develops within surrounding rock mass under the high geostress. The fractured shape of zonal disintegration was determined, and the radii of the fractured zones were found to fulfill the relationship of geometric progression. The numerical results were in accordance with the model test findings. The mechanism of the zonal disintegration was revealed by theoretical analysis based on fracture mechanics. The fractured zones are reportedly circular and concentric to the cavern. Each fracture zone ruptured at the elastic-plastic boundary of the surrounding rocks and then coalesced into the circular form. The geometric progression ratio was found to be related to the mechanical parameters and the ground stress of the surrounding rocks.

  4. Numerical simulation on zonal disintegration in deep surrounding rock mass.

    Science.gov (United States)

    Chen, Xuguang; Wang, Yuan; Mei, Yu; Zhang, Xin

    2014-01-01

    Zonal disintegration have been discovered in many underground tunnels with the increasing of embedded depth. The formation mechanism of such phenomenon is difficult to explain under the framework of traditional rock mechanics, and the fractured shape and forming conditions are unclear. The numerical simulation was carried out to research the generating condition and forming process of zonal disintegration. Via comparing the results with the geomechanical model test, the zonal disintegration phenomenon was confirmed and its mechanism is revealed. It is found to be the result of circular fracture which develops within surrounding rock mass under the high geostress. The fractured shape of zonal disintegration was determined, and the radii of the fractured zones were found to fulfill the relationship of geometric progression. The numerical results were in accordance with the model test findings. The mechanism of the zonal disintegration was revealed by theoretical analysis based on fracture mechanics. The fractured zones are reportedly circular and concentric to the cavern. Each fracture zone ruptured at the elastic-plastic boundary of the surrounding rocks and then coalesced into the circular form. The geometric progression ratio was found to be related to the mechanical parameters and the ground stress of the surrounding rocks.

  5. Tissue reaction surrounding miniscrews for orthodontic anchorage: An animal experiment

    Directory of Open Access Journals (Sweden)

    Stephanie Shih-Hsuan Chen

    2012-03-01

    Results and conclusions: (1 Tissue surrounding roots damaged by a miniscrew showed a significant inflammatory response. (2 Root resorption was occasionally observed after 3 weeks following insertion of a miniscrew even if the miniscrew was not in direct contact with the root. (3 Root repair was noted with a cementoblast lining along the resorption surface at as early as 3 weeks after miniscrew insertion. Alveolar bone filled in the lesion when the root damage was large so that the contour of the alveolar bone followed that of the damaged root, with the width of the periodontal ligament space being maintained. (4 Stable miniscrews were mainly those which did not contact adjacent roots, and for which the surrounding tissue showed only a small inflammatory response with some extent of direct bone contact around the miniscrew. On the contrary, most of the failed miniscrews were those which had direct contact with adjacent roots, and which exhibited severe tissue inflammation and were covered by thick layers of soft tissue. Failure was detected 3 weeks after insertion. Surprisingly, the epithelial lining surrounding the miniscrews might not have spontaneously resolved 6 weeks after screw removal. Persistent infection in the sinus tract was noted, and this would require attention.

  6. Transport processes in space plasmas

    International Nuclear Information System (INIS)

    Birn, J.; Elphic, R.C.; Feldman, W.C.

    1997-01-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project represents a comprehensive research effort to study plasma and field transport processes relevant for solar-terrestrial interaction, involving the solar wind and imbedded magnetic field and plasma structures, the bow shock of the Earth's magnetosphere and associated waves, the Earth's magnetopause with imbedded flux rope structures and their connection with the Earth, plasma flow in the Earth's magnetotail, and ionospheric beam/wave interactions. The focus of the work was on the interaction between plasma and magnetic and electric fields in the regions where different plasma populations exist adjacent to or superposed on each other. These are the regions of particularly dynamic plasma behavior, important for plasma and energy transport and rapid energy releases. The research addressed questions about how this interaction takes place, what waves, instabilities, and particle/field interactions are involved, how the penetration of plasma and energy through characteristic boundaries takes place, and how the characteristic properties of the plasmas and fields of the different populations influence each other on different spatial and temporal scales. These topics were investigated through combining efforts in the analysis of plasma and field data obtained through space missions with theory and computer simulations of the plasma behavior

  7. Study of aerosol sample interaction with dc plasma in the presence of oscillating magnetic field

    International Nuclear Information System (INIS)

    Stoiljkovic, M.M.; Pavlovic, M.S.; Savovic, J.; Kuzmanovic, M.; Marinkovic, M.

    2005-01-01

    Oscillating magnetic field was used to study the efficiency of the aerosol sample introduction into the dc plasma. At atmospheric plasmas, the effect of magnetic field is reduced to Lorentz forces on the current carrying plasma, which produces motion of the plasma. The motion velocity of dc plasma caused by oscillating magnetic field was correlated to spectral emission enhancement of analytes introduced as aerosols. Emission enhancement is the consequence of the reduced barrier to introduction of analyte species and aerosol particles into the hot plasma region. Two hypotheses described in the literature for the origin of the barrier are considered: (i) barrier induced by temperature field is based upon the thermophoretic forces on the aerosol particles when their radius is comparable to the molecular free path in the surrounding gas and (ii) barrier induced by radial electric field, recently described, that originates from gradients of charged particles in radial direction. Correlation between ionization energy of the analyte atoms with experimental emission enhancement obtained by the use of oscillating magnetic field indicates that mechanism (ii) based upon the radial electric field is predominant. The ultimate emission enhancement and possible analytical advantage is discussed

  8. Dependency of plasmon resonance sensitivity of colloidal gold nanoparticles on the identity of surrounding ionic media

    Science.gov (United States)

    Mehrdel, B.; Aziz, A. Abdul

    2018-03-01

    The plasmon resonance sensitivity of gold nanoparticles (AuNPs) in sodium chloride (NaCl) liquid in near-infrared to the visible spectral region was investigated. The correlation between NaCl concentration and refractive index was analyzed using concentration dependency and Lorenz-Lorenz methods. The first derivative method was applied to the measured absorption spectra to quantitatively evaluate the plasmon resonance sensitivity. To understand the influence of the identity of the surrounding medium on the plasmon resonance sensitivity, experiments were repeated by replacing NaCl with sodium hydroxide (NaOH), followed by phosphate buffered saline (PBS). Experimental results showed that NaCl is the most effective ionic surrounding medium, which gives prominent plasmon resonance response. AuNPs size can have a significant influence on the plasmon resonance sensitivity. For tiny AuNPs (∼10 nm AuNPs), the plasmon resonance is insensitive to the identity of the surrounding medium due to their low cross-section value.

  9. Logistics system as an effort of integration in the Mandalika Special Economic Zone and its surroundings

    Science.gov (United States)

    Suheri, T.; Melinda, W. G.

    2018-05-01

    Indonesia as one of the maritime countries with its territory in the form of an archipelago. A SEZ with an integrated logistics system is very influential on the value of tourism, especially marine tourism. The creation of logistics activities in the Mandalika SEZ as a tourism area formed from the export and import of products as a form of tourism promotion will attract many domestic and foreign tourists. The importance of a logistics system for both people and goods can support the investment system in the area of Mandalika SEZ. The logistics system can provide agglomeration of facilities and infrastructure to support tourist activities in terms of cargo distribution both locally and globally. Mandalika SEZ requires an integrated logistics system to improve national competitiveness in the form of physical system support such as commodity availability and city/regional infrastructure as well as non-physical infrastructure such as service providers and regulation in order to be sustainable. The logistics system also plays a strategic role in synchronizing and harmonizing progress between economies and between regions in order to avoid an imbalance with the surrounding area. This study aims to find out the performance of the existing logistics systems in the Mandalika area and its surrounding areas in order to formulate policies to integrate the logistics systems within and outside the region. This research used content analysis methodology.

  10. Comparison of the common spatial interpolation methods used to analyze potentially toxic elements surrounding mining regions.

    Science.gov (United States)

    Ding, Qian; Wang, Yong; Zhuang, Dafang

    2018-04-15

    The appropriate spatial interpolation methods must be selected to analyze the spatial distributions of Potentially Toxic Elements (PTEs), which is a precondition for evaluating PTE pollution. The accuracy and effect of different spatial interpolation methods, which include inverse distance weighting interpolation (IDW) (power = 1, 2, 3), radial basis function interpolation (RBF) (basis function: thin-plate spline (TPS), spline with tension (ST), completely regularized spline (CRS), multiquadric (MQ) and inverse multiquadric (IMQ)) and ordinary kriging interpolation (OK) (semivariogram model: spherical, exponential, gaussian and linear), were compared using 166 unevenly distributed soil PTE samples (As, Pb, Cu and Zn) in the Suxian District, Chenzhou City, Hunan Province as the study subject. The reasons for the accuracy differences of the interpolation methods and the uncertainties of the interpolation results are discussed, then several suggestions for improving the interpolation accuracy are proposed, and the direction of pollution control is determined. The results of this study are as follows: (i) RBF-ST and OK (exponential) are the optimal interpolation methods for As and Cu, and the optimal interpolation method for Pb and Zn is RBF-IMQ. (ii) The interpolation uncertainty is positively correlated with the PTE concentration, and higher uncertainties are primarily distributed around mines, which is related to the strong spatial variability of PTE concentrations caused by human interference. (iii) The interpolation accuracy can be improved by increasing the sample size around the mines, introducing auxiliary variables in the case of incomplete sampling and adopting the partition prediction method. (iv) It is necessary to strengthen the prevention and control of As and Pb pollution, particularly in the central and northern areas. The results of this study can provide an effective reference for the optimization of interpolation methods and parameters for unevenly distributed soil PTE data in mining areas. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Particulate matter (PM 10 ) in Istanbul: Origin, source areas and potential impact on surrounding regions

    Science.gov (United States)

    Koçak, M.; Theodosi, C.; Zarmpas, P.; Im, U.; Bougiatioti, A.; Yenigun, O.; Mihalopoulos, N.

    2011-12-01

    Water-soluble ions (Cl -, NO3-, SO42-, CO4-, Na +, NH4+, K +, Mg 2+,Ca 2+), water soluble organic carbon (WSOC), organic and elemental carbon (OC, EC) and trace metals (Al, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb) were measured in aerosol PM 10 samples above the megacity of Istanbul between November 2007 and June 2009. Source apportionment analysis using Positive Matrix Factorization (PMF) indicates that approximately 80% of the PM 10 is anthropogenic in origin (secondary, refuse incineration, fuel oil and solid fuel combustion and traffic). Crustal and sea salt account for 10.2 and 7.5% of the observed mass, respectively. In general, anthropogenic (except secondary) aerosol shows higher concentrations and contributions in winter. Mean concentration and contribution of crustal source is found to be more important during the transitional period due to mineral dust transport from North Africa. During the sampling period, 42 events exceeding the limit value of 50 μg m -3 are identified. A significant percentage (91%; n = 38) of these exceedances is attributed to anthropogenic sources. Potential Source Contribution Function analysis highlights that Istanbul is affected from distant sources from Balkans and Western Europe during winter and from Eastern Europe during summer. On the other hand, Istanbul sources influence western Black Sea and Eastern Europe during winter and Aegean and Levantine Sea during summer.

  12. New radiochronological data on the Franceville basin and the surrounding region

    International Nuclear Information System (INIS)

    Weber, F.; Bonhomme, M.

    1975-01-01

    After a brief presentation of the Francevillian series, the radiochronological data obtained some years ago are discussed, account being taken of possible connections of the series with the intrusive N'Goutou complex on one hand and the metamorphic Ogooue system on the other. If the syenitic N'Goutou intrusion is contemporary with the deposition of the sediments, the age given by the Rb-Sr isochrone of the Franceville basin (1740 or 1800 million years depending on the constants used), which cannot be distinguished from that of the syenites, agrees - within the margin of the analytical errors - with the age of the sedimentation. If, on the other hand, the syenitic intrusion is later, a greater age - possibly of the order of 2000 million years - can be envisaged for the deposition of the sediments. This would be confirmed if it were proved that the Franceville basin merges without any major discordance into the metamorphic Ogooue system, acquiring increasing metamorphism towards the north-west, and if it were demonstrated that a substantial magmatic event subsequently modified the apparent age of the series. The new measurements presented in the paper were performed at Strasbourg by the K-Ar method. The following samples were analysed: veined dolerites which cut through the Franceville basin and the base; a syenite from an intrusive complex in the Chaillu Massif; pelites from the Oklo deposit; a pelite sample obtained by drilling from the extreme base of the series. The dolerites have rather widely differing apparent ages which probably reflect a deposition about 850 million years ago and, in some cases, a more or less complete loss of radiogenic argon due to rearrangement of the fractures in the course of Mayombian folding about 500 million years ago. The Chaillu syenite has an apparent age of 2200 million years, which may be regarded as the latest date for its actual deposition. Thus, these different intrusions are not related in age with the syenitic N'Goutou complex. Whatever their stratigraphic level, the pelitic samples from the Franceville basin have apparent ages consistent with those found previously (1700-1800 million years). On the other hand, two samples from the wall of one of the reaction zones have lost (almost completely in one case) radiogenic argon. This is due to recent effects on the reaction zones of meteoric water circulation in the cracks

  13. Plasma device

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A method is described of providing electron beam heating of a high-density plasma to drive a fast liner to implode a structured microsphere. An annular relativistic electron beam is used to heat an annular plasma to kilovolt temperatures through streaming instabilities in the plasma. Energy deposited in the annular plasma then converges on a fast liner to explosively or ablatively drive the liner to convergence to implode the structured microsphere. (U.K.)

  14. Presence of VIM-Positive Pseudomonas Species in Chickens and Their Surrounding Environment.

    Science.gov (United States)

    Zhang, Rongmin; Liu, Zhihai; Li, Jiyun; Lei, Lei; Yin, Wenjuan; Li, Mei; Wu, Congming; Walsh, Timothy R; Wang, Yang; Wang, Shaolin; Wu, Yongning

    2017-07-01

    Metallo-β-lactamase gene bla VIM was identified on the chromosome of four Pseudomonas sp. isolates from a chicken farm, including one Pseudomonas aeruginosa isolate from a swallow ( Yanornis martini ), one Pseudomonas putida isolate from a fly, and two P. putida isolates from chickens. The four isolates shared two variants of bla VIM -carrying genomic contexts that resemble the corresponding regions of clinical metallo-β-lactamase-producing Pseudomonas spp. Our study suggests that the surveillance of carbapenemase-producing bacteria in livestock and their surrounding environment is urgently needed. Copyright © 2017 American Society for Microbiology.

  15. Plasma source ion implantation

    International Nuclear Information System (INIS)

    Conrad, J.R.; Forest, C.

    1986-01-01

    The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

  16. Merging and Splitting of Plasma Spheroids in a Dusty Plasma

    Science.gov (United States)

    Mikikian, Maxime; Tawidian, Hagop; Lecas, Thomas

    2012-12-01

    Dust particle growth in a plasma is a strongly disturbing phenomenon for the plasma equilibrium. It can induce many different types of low-frequency instabilities that can be experimentally observed, especially using high-speed imaging. A spectacular case has been observed in a krypton plasma where a huge density of dust particles is grown by material sputtering. The instability consists of well-defined regions of enhanced optical emission that emerge from the electrode vicinity and propagate towards the discharge center. These plasma spheroids have complex motions resulting from their mutual interaction that can also lead to the merging of two plasma spheroids into a single one. The reverse situation is also observed with the splitting of a plasma spheroid into two parts. These results are presented for the first time and reveal new behaviors in dusty plasmas.

  17. Plasma Simulation Program

    Energy Technology Data Exchange (ETDEWEB)

    Greenwald, Martin

    2011-10-04

    Many others in the fusion energy and advanced scientific computing communities participated in the development of this plan. The core planning team is grateful for their important contributions. This summary is meant as a quick overview the Fusion Simulation Program's (FSP's) purpose and intentions. There are several additional documents referenced within this one and all are supplemental or flow down from this Program Plan. The overall science goal of the DOE Office of Fusion Energy Sciences (FES) Fusion Simulation Program (FSP) is to develop predictive simulation capability for magnetically confined fusion plasmas at an unprecedented level of integration and fidelity. This will directly support and enable effective U.S. participation in International Thermonuclear Experimental Reactor (ITER) research and the overall mission of delivering practical fusion energy. The FSP will address a rich set of scientific issues together with experimental programs, producing validated integrated physics results. This is very well aligned with the mission of the ITER Organization to coordinate with its members the integrated modeling and control of fusion plasmas, including benchmarking and validation activities. [1]. Initial FSP research will focus on two critical Integrated Science Application (ISA) areas: ISA1, the plasma edge; and ISA2, whole device modeling (WDM) including disruption avoidance. The first of these problems involves the narrow plasma boundary layer and its complex interactions with the plasma core and the surrounding material wall. The second requires development of a computationally tractable, but comprehensive model that describes all equilibrium and dynamic processes at a sufficient level of detail to provide useful prediction of the temporal evolution of fusion plasma experiments. The initial driver for the whole device model will be prediction and avoidance of discharge-terminating disruptions, especially at high performance, which are a

  18. Lipid domains in intact fiber-cell plasma membranes isolated from cortical and nuclear regions of human eye lenses of donors from different age groups.

    Science.gov (United States)

    Raguz, Marija; Mainali, Laxman; O'Brien, William J; Subczynski, Witold K

    2015-03-01

    The results reported here clearly document changes in the properties and the organization of fiber-cell membrane lipids that occur with age, based on electron paramagnetic resonance (EPR) analysis of lens membranes of clear lenses from donors of age groups from 0 to 20, 21 to 40, and 61 to 80 years. The physical properties, including profiles of the alkyl chain order, fluidity, hydrophobicity, and oxygen transport parameter, were investigated using EPR spin-labeling methods, which also provide an opportunity to discriminate coexisting lipid domains and to evaluate the relative amounts of lipids in these domains. Fiber-cell membranes were found to contain three distinct lipid environments: bulk lipid domain, which appears minimally affected by membrane proteins, and two domains that appear due to the presence of membrane proteins, namely boundary and trapped lipid domains. In nuclear membranes the amount of boundary and trapped phospholipids as well as the amount of cholesterol in trapped lipid domains increased with the donors' age and was greater than that in cortical membranes. The difference between the amounts of lipids in domains uniquely formed due to the presence of membrane proteins in nuclear and cortical membranes increased with the donors' age. It was also shown that cholesterol was to a large degree excluded from trapped lipid domains in cortical membranes. It is evident that the rigidity of nuclear membranes was greater than that of cortical membranes for all age groups. The amount of lipids in domains of low oxygen permeability, mainly in trapped lipid domains, were greater in nuclear than cortical membranes and increased with the age of donors. These results indicate that the nuclear fiber cell plasma membranes were less permeable to oxygen than cortical membranes and become less permeable to oxygen with age. In clear lenses, age-related changes in the lens lipid and protein composition and organization appear to occur in ways that increase fiber

  19. Regionalism, Regionalization and Regional Development

    Directory of Open Access Journals (Sweden)

    Liviu C. Andrei

    2016-03-01

    Full Text Available Sustained development is a concept associating other concepts, in its turn, in the EU practice, e.g. regionalism, regionalizing and afferent policies, here including structural policies. This below text, dedicated to integration concepts, will limit on the other hand to regionalizing, otherwise an aspect typical to Europe and to the EU. On the other hand, two aspects come up to strengthen this field of ideas, i.e. the region (al-regionalism-(regional development triplet has either its own history or precise individual outline of terms.

  20. Dusty plasmas

    International Nuclear Information System (INIS)

    Jones, M.E.; Winske, D.; Keinigs, R.; Lemons, D.

    1996-01-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project has been to develop a fundamental understanding of dusty plasmas at the Laboratory. While dusty plasmas are found in space in galactic clouds, planetary rings, and cometary tails, and as contaminants in plasma enhanced fabrication of microelectronics, many of their properties are only partially understood. Our work has involved both theoretical analysis and self-consistent plasma simulations to understand basic properties of dusty plasmas related to equilibrium, stability, and transport. Such an understanding can improve the control and elimination of plasma dust in industrial applications and may be important in the study of planetary rings and comet dust tails. We have applied our techniques to the study of charging, dynamics, and coagulation of contaminants in plasma processing reactors for industrial etching and deposition processes and to instabilities in planetary rings and other space plasma environments. The work performed in this project has application to plasma kinetics, transport, and other classical elementary processes in plasmas as well as to plasma waves, oscillations, and instabilities

  1. Plasma chromatography

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    This book examines the fundamental theory and various applications of ion mobility spectroscopy. Plasma chromatography developed from research on the diffusion and mobility of ions. Topics considered include instrument design and description (e.g., performance, spectral interpretation, sample handling, mass spectrometry), the role of ion mobility in plasma chromatography (e.g., kinetic theory of ion transport), atmospheric pressure ionization (e.g., rate equations), the characterization of isomers by plasma chromatography (e.g., molecular ion characteristics, polynuclear aromatics), plasma chromatography as a gas chromatographic detection method (e.g., qualitative analysis, continuous mobility monitoring, quantitative analysis), the analysis of toxic vapors by plasma chromatography (e.g., plasma chromatograph calibration, instrument control and data processing), the analysis of semiconductor devices and microelectronic packages by plasma chromatography/mass spectroscopy (e.g., analysis of organic surface contaminants, analysis of water in sealed electronic packages), and instrument design and automation (hardware, software)

  2. Experimental observation of nonlinear behaviour in a helium plasma discharge in the presence of a nonuniform magnetic field

    International Nuclear Information System (INIS)

    Toma, M.; Sanduloviciu, M.

    1994-01-01

    The nonlinear behaviour in an electrical discharge plasma due to the action of an external nonuniform magnetic field is presented. The discharge geometry and the magnetic field configuration ('inverse' cylindrical magnetron discharge) were so chosen that there is a possibility to control the net electron flux in a certain region of a positive electrode. The plasma discharge nonlinearity manifested in the profile of the current-voltage, current-magnetic field and current-gas pressure characteristics by the appearance of the anomalous negative resistance, in the bistability and hysteresis and also in the periodical and chaotic variation of the discharge current. The profile of the current variation vs control discharge parameters was related to the appearance of a space charge structure in the shape of nearly spherical bulges, delimited from the surrounding plasma by a double layer. (Author)

  3. Blooming Trees: Substructures and Surrounding Groups of Galaxy Clusters

    Science.gov (United States)

    Yu, Heng; Diaferio, Antonaldo; Serra, Ana Laura; Baldi, Marco

    2018-06-01

    We develop the Blooming Tree Algorithm, a new technique that uses spectroscopic redshift data alone to identify the substructures and the surrounding groups of galaxy clusters, along with their member galaxies. Based on the estimated binding energy of galaxy pairs, the algorithm builds a binary tree that hierarchically arranges all of the galaxies in the field of view. The algorithm searches for buds, corresponding to gravitational potential minima on the binary tree branches; for each bud, the algorithm combines the number of galaxies, their velocity dispersion, and their average pairwise distance into a parameter that discriminates between the buds that do not correspond to any substructure or group, and thus eventually die, and the buds that correspond to substructures and groups, and thus bloom into the identified structures. We test our new algorithm with a sample of 300 mock redshift surveys of clusters in different dynamical states; the clusters are extracted from a large cosmological N-body simulation of a ΛCDM model. We limit our analysis to substructures and surrounding groups identified in the simulation with mass larger than 1013 h ‑1 M ⊙. With mock redshift surveys with 200 galaxies within 6 h ‑1 Mpc from the cluster center, the technique recovers 80% of the real substructures and 60% of the surrounding groups; in 57% of the identified structures, at least 60% of the member galaxies of the substructures and groups belong to the same real structure. These results improve by roughly a factor of two the performance of the best substructure identification algorithm currently available, the σ plateau algorithm, and suggest that our Blooming Tree Algorithm can be an invaluable tool for detecting substructures of galaxy clusters and investigating their complex dynamics.

  4. Isoperimetric inequalities in surround system and space science

    OpenAIRE

    JiaJin Wen; Jun Yuan; ShanHe Wu

    2016-01-01

    Abstract By means of the algebraic, analysis, convex geometry, computer, and inequality theories we establish the following isoperimetric inequality in the centered 2-surround system S ( 2 ) { P , Γ , l } $S^{(2)} \\{P,\\varGamma ,l \\}$ : ( 1 | Γ | ∮ Γ r ¯ P p ) 1 / p ⩽ | Γ | 4 π sin l π | Γ | [ csc l π | Γ | + cot 2 l π | Γ | ln ( tan l π | Γ | + sec l π | Γ | ) ] , ∀ p ⩽ − 2 . $$\\begin{aligned}& \\biggl(\\frac{1}{|\\varGamma |} \\oint_{\\varGamma }\\bar{r}_{P}^{p} \\biggr)^{1/p}\\leqslant\\frac{|\\varG...

  5. Induced radioactivity in a 4 MW target and its surroundings

    CERN Document Server

    Agosteo, Stefano; Otto, Thomas; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump was performed by the Monte Carlo hadronic cascade code FLUKA. The aim was both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation.

  6. Diversity of vascular plants of Piestany and surroundings

    International Nuclear Information System (INIS)

    Penzesova, A.; Galusova, T.

    2013-01-01

    In the present work is a summary of the results of floristic research aimed at determining diversity of vascular plants of Piestany and its surroundings. Plant taxa we determined using the designation keys. We have compiled a list of plant species occurring in the monitored area, we evaluated the selected botanical-phytogeographical characteristics of flora, we've put together a list of local protected, endangered and rare species and a list of local invasive and expansive species according to sources. (Authors)

  7. One Japanese case on taxation surrounding foreign trust

    OpenAIRE

    SUZUKI, Yuya

    2015-01-01

    Taxation surrounding trust at cross-border situation is paid attention to byworldwide basis. Japan is not exception. According to recent Japanesejurisprudence, where a trust had been established in accordance with State law ofNew Jersey, the U.S., it was disputed whether or not the act settling that trust fellwithin “shintaku koui (an act of trust)” and one of the related members, who had beena minor child at that time, fell within “jyueki sha (beneficiary)” under JapaneseInheritance Tax Act....

  8. Metastability in Magnetically Confined Plasmas

    International Nuclear Information System (INIS)

    Fong, B.H.; Cowley, S.C.; Hurricane, O.A.

    1999-01-01

    The parameter space of magnetically confined plasmas near marginal instability for interchange-type modes is divided into three regions according to qualitative stability properties. Region I is linearly stable though nonlinearly unstable to large excitations. Region II is linearly unstable, nonlinearly stable to small excitations, and nonlinearly unstable to large excitations. Region III is linearly and nonlinearly unstable. For an equilibrium evolving through marginal stability, region III and therefore explosive instability are inevitably encountered. copyright 1999 The American Physical Society

  9. A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome.

    Science.gov (United States)

    Moaddel, Ruin; Venkata, Swarajya Lakshmi Vattem; Tanga, Mary J; Bupp, James E; Green, Carol E; Iyer, Lalitha; Furimsky, Anna; Goldberg, Michael E; Torjman, Marc C; Wainer, Irving W

    2010-10-15

    A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in complex regional pain syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)- and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric metabolites hydroxynorketamine, (2S,6S)-/(2R,6R)-HNK and two hydroxyketamines, (2S,6S)-HKet and (2S,6R)-Hket. In this method, (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK and the diastereomeric hydroxyl-metabolites were separated and quantified using a C(18) stationary phase and the relative enantiomeric concentrations of (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK were determined using an AGP-CSP. The analysis of the results of microsomal incubations of (R)- and (S)-Ket and a plasma and urine sample from a CRPS patient indicated the presence of 10 additional compounds and glucuronides. The data from the analysis of the patient sample also demonstrated that a series of HNK metabolites were the primary metabolites in plasma and (R)- and (S)-DHNK were the major metabolites found in urine. The results suggest that norKet is the initial, but not the primary metabolite and that downstream norKet metabolites play a role in (R,S)-Ket-related pain relief in CRPS patients. Published by Elsevier B.V.

  10. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    International Nuclear Information System (INIS)

    Thode, L.E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region are described. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises dt, dd, hydrogen boron or similar thermonuclear gas at a density of 1017 to 1020 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 mev, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner

  11. Regional Ocean Modeling System (ROMS): Samoa

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 7-day, 3-hourly forecast for the region surrounding the islands of Samoa at approximately 3-km resolution. While considerable...

  12. Regional Ocean Modeling System (ROMS): Guam

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 6-day, 3-hourly forecast for the region surrounding Guam at approximately 2-km resolution. While considerable effort has been...

  13. Regional Ocean Modeling System (ROMS): Oahu

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 7-day, 3-hourly forecast for the region surrounding the island of Oahu at approximately 1-km resolution. While considerable...

  14. Regional Ocean Modeling System (ROMS): CNMI

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Regional Ocean Modeling System (ROMS) 7-day, 3-hourly forecast for the region surrounding the Commonwealth of the Northern Mariana Islands (CNMI) at approximately...

  15. The Impact of Temperatures on the Stability of Rocks Surrounding a Single Fracture

    Science.gov (United States)

    Zhang, Yan; Li, Ning; Dai, Jun

    2018-05-01

    Research on the influence of temperature and the accompanying stress on the stability of the rocks surrounding an underground tunnel has become ever more important. This paper constructs a geometric model of a single-fracture tunnel by combining a high-temperature underground tunnel as the object of study with an example that uses a high-temperature tunnel segment in the water diversion tunnel of a hydropower station in Xinjiang. Based on the relevant theoretical analysis, with the consideration of different working conditions, a numerical experimental analysis was conducted to determine the two-dimensional transient temperature field distribution of the tunnel rock mass by using a numerical analysis software. The experimental data was consistent with the measured data. The calculated results show the following: a. when the temperature difference is greater, the stress concentration is higher near the fracture of the surrounding rock; b. the degree of the stress concentration in the crack tip region is not positively correlated to the distance, and there is a sensitive region where the stress varies.

  16. Cortical Surround Interactions and Perceptual Salience via Natural Scene Statistics.

    Directory of Open Access Journals (Sweden)

    Ruben Coen-Cagli

    Full Text Available Spatial context in images induces perceptual phenomena associated with salience and modulates the responses of neurons in primary visual cortex (V1. However, the computational and ecological principles underlying contextual effects are incompletely understood. We introduce a model of natural images that includes grouping and segmentation of neighboring features based on their joint statistics, and we interpret the firing rates of V1 neurons as performing optimal recognition in this model. We show that this leads to a substantial generalization of divisive normalization, a computation that is ubiquitous in many neural areas and systems. A main novelty in our model is that the influence of the context on a target stimulus is determined by their degree of statistical dependence. We optimized the parameters of the model on natural image patches, and then simulated neural and perceptual responses on stimuli used in classical experiments. The model reproduces some rich and complex response patterns observed in V1, such as the contrast dependence, orientation tuning and spatial asymmetry of surround suppression, while also allowing for surround facilitation under conditions of weak stimulation. It also mimics the perceptual salience produced by simple displays, and leads to readily testable predictions. Our results provide a principled account of orientation-based contextual modulation in early vision and its sensitivity to the homogeneity and spatial arrangement of inputs, and lends statistical support to the theory that V1 computes visual salience.

  17. Effectively Communicating the Uncertainties Surrounding Ebola Virus Transmission.

    Directory of Open Access Journals (Sweden)

    Andy Kilianski

    2015-10-01

    Full Text Available The current Ebola virus outbreak has highlighted the uncertainties surrounding many aspects of Ebola virus virology, including routes of transmission. The scientific community played a leading role during the outbreak-potentially, the largest of its kind-as many of the questions surrounding ebolaviruses have only been interrogated in the laboratory. Scientists provided an invaluable resource for clinicians, public health officials, policy makers, and the lay public in understanding the progress of Ebola virus disease and the continuing outbreak. Not all of the scientific communication, however, was accurate or effective. There were multiple instances of published articles during the height of the outbreak containing potentially misleading scientific language that spurred media overreaction and potentially jeopardized preparedness and policy decisions at critical points. Here, we use articles declaring the potential for airborne transmission of Ebola virus as a case study in the inaccurate reporting of basic science, and we provide recommendations for improving the communication about unknown aspects of disease during public health crises.

  18. Effectively Communicating the Uncertainties Surrounding Ebola Virus Transmission.

    Science.gov (United States)

    Kilianski, Andy; Evans, Nicholas G

    2015-10-01

    The current Ebola virus outbreak has highlighted the uncertainties surrounding many aspects of Ebola virus virology, including routes of transmission. The scientific community played a leading role during the outbreak-potentially, the largest of its kind-as many of the questions surrounding ebolaviruses have only been interrogated in the laboratory. Scientists provided an invaluable resource for clinicians, public health officials, policy makers, and the lay public in understanding the progress of Ebola virus disease and the continuing outbreak. Not all of the scientific communication, however, was accurate or effective. There were multiple instances of published articles during the height of the outbreak containing potentially misleading scientific language that spurred media overreaction and potentially jeopardized preparedness and policy decisions at critical points. Here, we use articles declaring the potential for airborne transmission of Ebola virus as a case study in the inaccurate reporting of basic science, and we provide recommendations for improving the communication about unknown aspects of disease during public health crises.

  19. REMOTE SENSING EFFICIENCY FOR URBAN ANALYSIS OF MECCA AND SURROUNDS

    Directory of Open Access Journals (Sweden)

    A. Imam

    2016-06-01

    Full Text Available Situated in the southwest of Saudi Arabia, Mecca is considered the spiritual capital of one and a half billion worldwide Muslims. The city is visited by millions of pilgrims every year. It has undergone significant changes in land cover (LC since the government first embarked on a series of ambitious development projects 20 years ago to accommodate the growing number of pilgrims and citizens. The main objective of our study is to detect, identify, analyze and measure the evolving land cover and urban morphology composition from multi-temporal satellite images. To characterize the morphological change during a period of twenty years, four satellite images, acquired in 1998 by Landsat TM and in 2003, 2008 and 2013 by Landsat ETM+, were classified into five main categories: Urban, Street, Soil and Vegetation. In addition, DEM has been extracted and included as Mountain. Change detection (CD analysis is applied using post-classification comparison and GIS. As part of the study, morphological index, such as, Entropy is included for better understanding of urban structures behaviour. Mecca and its surroundings show a noticeable increase in urban and vegetation cover. Urban cover (UC changes were divided into five radial directions: Northeast, Southeast, Southwest, East, and Northwest. These changes are influenced by mountain ranges surrounding the city and the highways. These revelations can play a significant role towards future planning and development activities, which may further promote urban growth.

  20. Remote Sensing Efficiency for Urban Analysis of Mecca and Surrounds

    Science.gov (United States)

    Imam, Ayman; Alhaddad, Bahaa; Roca, Josep

    2016-06-01

    Situated in the southwest of Saudi Arabia, Mecca is considered the spiritual capital of one and a half billion worldwide Muslims. The city is visited by millions of pilgrims every year. It has undergone significant changes in land cover (LC) since the government first embarked on a series of ambitious development projects 20 years ago to accommodate the growing number of pilgrims and citizens. The main objective of our study is to detect, identify, analyze and measure the evolving land cover and urban morphology composition from multi-temporal satellite images. To characterize the morphological change during a period of twenty years, four satellite images, acquired in 1998 by Landsat TM and in 2003, 2008 and 2013 by Landsat ETM+, were classified into five main categories: Urban, Street, Soil and Vegetation. In addition, DEM has been extracted and included as Mountain. Change detection (CD) analysis is applied using post-classification comparison and GIS. As part of the study, morphological index, such as, Entropy is included for better understanding of urban structures behaviour. Mecca and its surroundings show a noticeable increase in urban and vegetation cover. Urban cover (UC) changes were divided into five radial directions: Northeast, Southeast, Southwest, East, and Northwest. These changes are influenced by mountain ranges surrounding the city and the highways. These revelations can play a significant role towards future planning and development activities, which may further promote urban growth.

  1. MRI of normal pituitary glands and their surrounding structures

    International Nuclear Information System (INIS)

    Sato, Yoshiyuki

    1991-01-01

    Normal MRI appearances of the pituitary glands and their surrounding structures were evaluated in 332 patients without sellar and parasellar diseases. The height of the pituitary gland was maximum at 10-19 years of age reflecting hormonal activity. The width of the pituitary gland decreased, while that of the cavernous sinus increased with aging. This is probably due to atherosclerotic change of the internal carotid artery. Females younger than 30 years of age tended to show a convex upper surface of the pituitary gland and the displacement of the pituitary stalk was common after 50 years of age. Almost all of the anterior lobe of the pituitary gland showed isointensity relative to the pons or cerebral cortex and the majority (85.1%) of the posterior lobe showed hyperintensity. However, the anterior lobe in 2 newborns showed hyperintensity similar to the normal posterior lobe in adults. The posterior lobe was located off the midline in 19.1% of the subjects. One case of pars intermedia cyst was discovered among 14 subjects who were administered Gd-DTPA. The dural membrane between the pituitary gland and cavernous sinus was recognizable only in 8.6% on the right side and 7.5% on the left side. Primary empty sella was identified in 4.5%. Knowledge of the above normal ranges and variations of the pituitary gland and its surrounding structures is important in diagnosing sellar and parasellar lesions. (author) 52 refs

  2. Study of Interaction between Supersonic Flow and Rods Surrounded by Porous Cavity

    Institute of Scientific and Technical Information of China (English)

    Minoru YAGA; Kenji YAMAMOTO; Piotr DOERFFER; Kenyu OYAKAWA

    2006-01-01

    In this paper,some preliminary calculations and the experiments were performed to figure out the flow field,in which some rods were normally inserted into the main flow surrounded by a porous cavity.As a result,it is found that the starting shock wave severely interacts with the rods,the bow shock wave,its reflections,and the porous wall,which are numerically well predicted at some conditions.Moreover,inserting the rods makes the pressure on the upper wall in the porous region increase when the main flow in the porous region is completely supersonic.The calculations also suggest that three rods cause the widest suction area.

  3. Earthquake hypocenter relocation using double difference method in East Java and surrounding areas

    International Nuclear Information System (INIS)

    C, Aprilia Puspita; Nugraha, Andri Dian; Puspito, Nanang T

    2015-01-01

    Determination of precise hypocenter location is very important in order to provide information about subsurface fault plane and for seismic hazard analysis. In this study, we have relocated hypocenter earthquakes in Eastern part of Java and surrounding areas from local earthquake data catalog compiled by Meteorological, Climatological, and Geophysical Agency of Indonesia (MCGA) in time period 2009-2012 by using the double-difference method. The results show that after relocation processes, there are significantly changes in position and orientation of earthquake hypocenter which is correlated with the geological setting in this region. We observed indication of double seismic zone at depths of 70-120 km within the subducting slab in south of eastern part of Java region. Our results will provide useful information for advance seismological studies and seismic hazard analysis in this study

  4. Physical geography of the Nete basin and surroundings; Fysische geografie van het Netebekken en omgeving

    Energy Technology Data Exchange (ETDEWEB)

    Beerten, K.

    2011-05-15

    The report briefly describes the main features of the physical geography of the Nete basin (Campine region, Belgium) and its immediate surroundings. First, an integrated overview of the topography, morphology and hydrography is given. This overview serves as the basis for the assessment of the morphological stability of the region and also explains the relationship between the topography and the hydrology. Furthermore, special attention is paid to soil science including a quantitative survey of some soil characteristics data. Another part of this report deals with erosion processes caused by water and wind action, and the (potential) impact on the morphology. Finally, the palaeogeographical evolution during the Quaternary is discussed. This evolution shows that the environment is stable over 10 000 years or more in the current and similar climatic conditions. Altering climatic conditions, notably glacial-interglacial periods, have impacted erosion with periods of strong erosion.

  5. Earthquake hypocenter relocation using double difference method in East Java and surrounding areas

    Energy Technology Data Exchange (ETDEWEB)

    C, Aprilia Puspita [Geophysical Engineering Program, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung (Indonesia); Meteorological, Climatological, and Geophysical Agency (MCGA) of Indonesian, Jakarta (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Geophysical Engineering Program, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung (Indonesia); Puspito, Nanang T [Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung (Indonesia)

    2015-04-24

    Determination of precise hypocenter location is very important in order to provide information about subsurface fault plane and for seismic hazard analysis. In this study, we have relocated hypocenter earthquakes in Eastern part of Java and surrounding areas from local earthquake data catalog compiled by Meteorological, Climatological, and Geophysical Agency of Indonesia (MCGA) in time period 2009-2012 by using the double-difference method. The results show that after relocation processes, there are significantly changes in position and orientation of earthquake hypocenter which is correlated with the geological setting in this region. We observed indication of double seismic zone at depths of 70-120 km within the subducting slab in south of eastern part of Java region. Our results will provide useful information for advance seismological studies and seismic hazard analysis in this study.

  6. Modeling of cylindrical surrounding gate MOSFETs including the fringing field effects

    International Nuclear Information System (INIS)

    Gupta, Santosh K.; Baishya, Srimanta

    2013-01-01

    A physically based analytical model for surface potential and threshold voltage including the fringing gate capacitances in cylindrical surround gate (CSG) MOSFETs has been developed. Based on this a subthreshold drain current model has also been derived. This model first computes the charge induced in the drain/source region due to the fringing capacitances and considers an effective charge distribution in the cylindrically extended source/drain region for the development of a simple and compact model. The fringing gate capacitances taken into account are outer fringe capacitance, inner fringe capacitance, overlap capacitance, and sidewall capacitance. The model has been verified with the data extracted from 3D TCAD simulations of CSG MOSFETs and was found to be working satisfactorily. (semiconductor devices)

  7. FY 2000 report on the results of the regional consortium R and D project - Regional consortium energy R and D. Third year report. R and D of a hybrid pulse plasma coating (HPPC) system; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo - chiiki consortium energy kenkyu kaihatsu. Hybrid gata pulse plasma coating (HPPC) system no kenkyu kaihatsu (dai 3 nendo) seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The development was proceeded with of the surface reforming technology system in which plasma CVD technology and PSII (plasma source ion implantation) technology are connected. HPPC forms DLC (diamond like carbon) layers excellent in adhesion and ceramic layers on the surface of work pieces such as complicatedly shaped dies and tools/sliding parts. Element technologies are the raw material gas pulse introducing technology for efficiently introducing raw materials into the reaction container in a state of gas, high density plasma formation technology and pulse plasma formation technology, minus pulse voltage application technology for vertically implanting various ions on the surface of complicatedly shaped work pieces, and advanced hybrid control technology enabling the control of ion species/implantation amount/layer formation speed. In FY 2000, using the prototype of the HPPC system, studies were made of the development of the DLC layer process and the low temperature DLC layer process, and development and commercialization of technology to improve throwing power, etc. (NEDO)

  8. Electromagnetic separator of plasma

    International Nuclear Information System (INIS)

    Gasilin, V.V.; Nezovibatko, Yu.N.; Poklepach, G.S.; Shvets, O.M.; Taran, V.S.; Tereshin, V.I.

    2005-01-01

    The progress in the widespread utilization of the PVD methods is determined in many respects by the plasma quality and, therefore, the necessity of an application of plasma separators, in particular magnetic separators. One needs to note that traditional magnetic separators have a number of problems their using, namely their unwieldiness, the presence of the isolated cameras and so on. We have proposed, manufactured and investigated the simple separator of plasma that doesn't require using additional cameras. As a source of metallic plasma the standard cathode vaporizer in the installation 'BULAT 6' was in use. Plasma stream from the cathode flowed through the not protected by isolation spiral solenoid. The solenoid input (from the cathode side) was under floating potential. The solenoid output was connected to the autonomous power supply system. The solenoid was prepared with stride winding and 90 degree turn. The solenoid current was 20-90 A and the solenoid voltage with respect to the vessel (earth) was +15 V. In this case drifting charged particles could freely fly out from the interior solenoid region to its boundary. The glow of the turned flow of plasma was observed during the supplying of the cathode and the solenoid. Plasma flow was separated from the coils and extended along the axis of solenoid. One can assume that this device ensures radial electric with respect to the bulk of plasma (the diameter of the bulk of plasma is comparable with the cathode diameter), the toroidal magnetic field, produced by solenoid, was of an order of 20 Oe. Magnetic field strength was sufficient for the magnetization of electrons, but it was rather small for magnetizing the ions and charged micro-droplets. The experiments carried out with aluminum cathode on the deposition of coatings at the stainless steel substrate have shown the high effectiveness of this separator operation. Coatings without droplets were obtained also on the glass substrate with HF- displacement

  9. Cytoplasmic movement profiles of mouse surrounding nucleolus and not-surrounding nucleolus antral oocytes during meiotic resumption.

    Science.gov (United States)

    Bui, Thi Thu Hien; Belli, Martina; Fassina, Lorenzo; Vigone, Giulia; Merico, Valeria; Garagna, Silvia; Zuccotti, Maurizio

    2017-05-01

    Full-grown mouse antral oocytes are classified as surrounding nucleolus (SN) or not-surrounding nucleolus (NSN), depending on the respective presence or absence of a ring of Hoechst-positive chromatin surrounding the nucleolus. In culture, both types of oocytes resume meiosis and reach the metaphase II (MII) stage, but following insemination, NSN oocytes arrest at the two-cell stage whereas SN oocytes may develop to term. By coupling time-lapse bright-field microscopy with image analysis based on particle image velocimetry, we provide the first systematic measure of the changes to the cytoplasmic movement velocity (CMV) occurring during the germinal vesicle-to-MII (GV-to-MII) transition of these two types of oocytes. Compared to SN oocytes, NSN oocytes display a delayed GV-to-MII transition, which can be mostly explained by retarded germinal vesicle break down and first polar body extrusion. SN and NSN oocytes also exhibit significantly different CMV profiles at four main time-lapse intervals, although this difference was not predictive of SN or NSN oocyte origin because of the high variability in CMV. When CMV profile was analyzed through a trained artificial neural network, however, each single SN or NSN oocyte was blindly identified with a probability of 92.2% and 88.7%, respectively. Thus, the CMV profile recorded during meiotic resumption may be exploited as a cytological signature for the non-invasive assessment of the oocyte developmental potential, and could be informative for the analysis of the GV-to-MII transition of oocytes of other species. © 2017 Wiley Periodicals, Inc.

  10. The interaction of a flowing plasma with a dipole magnetic field: measurements and modelling of a diamagnetic cavity relevant to spacecraft protection

    International Nuclear Information System (INIS)

    Bamford, R; Bradford, J; Bingham, R; Gargate, L; Hapgood, M; Stamper, R; Gibson, K J; Thornton, A J; Silva, L O; Fonseca, R A; Norberg, C; Todd, T

    2008-01-01

    Here we describe a new experiment to test the shielding concept of a dipole-like magnetic field and plasma, surrounding a spacecraft forming a 'mini magnetosphere'. Initial laboratory experiments have been conducted to determine the effectiveness of a magnetized plasma barrier to be able to expel an impacting, low beta, supersonic flowing energetic plasma representing the solar wind. Optical and Langmuir probe data of the plasma density, the plasma flow velocity and the intensity of the dipole field clearly show the creation of a narrow transport barrier region and diamagnetic cavity virtually devoid of energetic plasma particles. This demonstrates the potential viability of being able to create a small 'hole' in a solar wind plasma, of the order of the ion Larmor orbit width, in which an inhabited spacecraft could reside in relative safety. The experimental results have been quantitatively compared with a 3D particle-in-cell 'hybrid' code simulation that uses kinetic ions and fluid electrons, showing good qualitative agreement and excellent quantitative agreement. Together the results demonstrate the pivotal role of particle kinetics in determining generic plasma transport barriers.

  11. Overview of geologic and geohydrologic conditions at the Finnsjoen site and its surroundings

    International Nuclear Information System (INIS)

    Ahlbom, K.; Tiren, S.

    1991-01-01

    The geologic and tectonic conditions of the Finnsjoen site and its surroundings have been studied on several scales ranging from regional to site scale. The Finnsjoen study is situated within a 50 square km shear lens. This lens is a part of a regional, c.20-30 km wide, WNW trending shear belt that was developed 1600-1800 million years ago. The final repository for reactor waste at Forsmark is also situated within this shear belt. The Finnsjoen Rock Block, bounded by regional and semi-regional fracture zones, constitute the main part of the Finnsjoen site. The size of the block is about 6 square km. A northeasterly trending fracture zone, Zone 1, divides this block into two lower order blocks, the northern and the southern block. In general, interpreted fracture zones, as well as the rock mass in general, are far better known in the northern Finnsjoen block compared to the southern block. This is due to extensive and detailed investigations of a gently dipping fracture zone, Zone 2, in the northern block. A tectonic model including 14 fracture zones is suggested for the Finnsjoen site and its surroundings. These zones have mainly been interpreted from lineament maps and to some extent from borehole measurements. The lack of borehole data implies that many of interpreted fracture zones, especially in the southern block outside the Finnsjoen site, should be regarded as tentative. The good general knowledge of the geologic and geohydrologic conditions in the northern Finnsjoen block, and possible stagnant groundwater conditions below Zone 2, makes the northern block the most suitable location for the generic repository at the Finnsjoen site. (authors)

  12. Plasma physics

    CERN Document Server

    Drummond, James E

    1961-01-01

    A historic snapshot of the field of plasma physics, this fifty-year-old volume offers an edited collection of papers by pioneering experts in the field. In addition to assisting students in their understanding of the foundations of classical plasma physics, it provides a source of historic context for modern physicists. Highly successful upon its initial publication, this book was the standard text on plasma physics throughout the 1960s and 70s.Hailed by Science magazine as a ""well executed venture,"" the three-part treatment ranges from basic plasma theory to magnetohydrodynamics and microwa

  13. MAPPING THE SURROUNDINGS AS A REQUIREMENT FOR AUTONOMOUS DRIVING

    Directory of Open Access Journals (Sweden)

    M. Steininger

    2016-11-01

    Full Text Available Motivated by the hype around driverless cars and the challenges of the sensor integration and data processing, this paper presents a model for using a XBox One Microsoft Kinect stereo camera as sensor for mapping the surroundings. Today, the recognition of the environment of the car is mostly done by a mix of sensors like LiDAR, RADAR and cameras. In the case of the outdoor delivery challenge Robotour 2016 with model cars in scale 1:5, it is our goal to solve the task with one camera only. To this end, a three-stage approach was developed. The test results show that our approach can detect and locate objects at a range of up to eight meters in order to incorporate them as barriers in the navigation process.

  14. Natural occurring radioactivity in Palmyra and its surrounding

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Shwekani, R.; Raja, G.; Hushari, M.; Al-Hent, R.; Issa, M.

    2006-06-01

    In this work, the natural radiation background has been carried out for Palmyra city and its surroundings area. The study has covered gamma radiation measurements, indoor radon gas concentration and radionuclides levels in environmental samples (soil, water, plat). The results showed that indoor radon gas concentrations and radiation exposure rates are within the background levels. Also, the results showed that there is no artificial radiation in the area and there is no correlation between the natural radiation levels and the reported cancer cases. Therefore, the reported cancer cases in this area may be due to non-radiation cases, which must be investigated, or they are within the natural levels in Syria unless accurate statistics proves the opposite. (author)

  15. Precision Security: Integrating Video Surveillance with Surrounding Environment Changes

    Directory of Open Access Journals (Sweden)

    Wenfeng Wang

    2018-01-01

    Full Text Available Video surveillance plays a vital role in maintaining the social security although, until now, large uncertainty still exists in danger understanding and recognition, which can be partly attributed to intractable environment changes in the backgrounds. This article presents a brain-inspired computing of attention value of surrounding environment changes (EC with a processes-based cognition model by introducing a ratio value λ of EC-implications within considered periods. Theoretical models for computation of warning level of EC-implications to the universal video recognition efficiency (quantified as time cost of implication-ratio variations from λk to λk+1, k=1,2,… are further established. Imbedding proposed models into the online algorithms is suggested as a future research priority towards precision security for critical applications and, furthermore, schemes for a practical implementation of such integration are also preliminarily discussed.

  16. A Study of the Flow Field Surrounding Interacting Line Fires

    Directory of Open Access Journals (Sweden)

    Trevor Maynard

    2016-01-01

    Full Text Available The interaction of converging fires often leads to significant changes in fire behavior, including increased flame length, angle, and intensity. In this paper, the fluid mechanics of two adjacent line fires are studied both theoretically and experimentally. A simple potential flow model is used to explain the tilting of interacting flames towards each other, which results from a momentum imbalance triggered by fire geometry. The model was validated by measuring the velocity field surrounding stationary alcohol pool fires. The flow field was seeded with high-contrast colored smoke, and the motion of smoke structures was analyzed using a cross-correlation optical flow technique. The measured velocities and flame angles are found to compare reasonably with the predicted values, and an analogy between merging fires and wind-blown flames is proposed.

  17. Teacher Leadership: Everyday Practices Surrounding Work- Related Stress

    Directory of Open Access Journals (Sweden)

    Chiweshe Nigel

    2015-06-01

    Full Text Available This interpretivist study contributes to our scholarly understanding of how everyday practices surrounding work-related stress in education affect teacher leadership and successful learning outcomes. Insights are drawn from our long-standing engagement in the field where we observed how teaching staff, students, and management interacted. These observations were supplemented by in-depth interviews with 20 teaching staff. Our findings reveal competing demands and practices across the individual intrapersonal environment and the work related environment. There were three key themes that emerged in answer to the core research question: 1 the role of relational practices in managing teacher burnout, 2 the role of surveillance practices in education and 3 the role of assimilating practices in education. Drawing insights from these practices, we develop a conceptual framework that will help us to see relations at work anew, and develop a deeper understanding of ‘sickies’, motivation, learning outcomes and teacher leadership opportunities in education

  18. The surrounding tissue modifies the placental stem villous vascular responses

    DEFF Research Database (Denmark)

    Brøgger, Torbjørn; Forman, Axel; Aalkjær, Christian

    2014-01-01

    is available. In-depth understanding of the mechanisms involved in control of placental vascular tone are needed to develop new tissue targets for therapeutic intervention. Method: From fresh born placentas segments of stem villous arteries were carefully dissected. The artery branches were divided....... The surrounding trophoblast was removed from one end and left intact in the other, and the segment was divided to give two ring preparations, with or without trophoblast. The preparations were mounted in wire myographs and responses to vasoactive agents were compared. Results: pD2values for PGF2α, Tx-analog U...... or endotheline-1. These differences partly disappeared in the presence of L-NAME. Conclusion: The perivascular tissue significantly reduces sensitivity and force development of stem villous arteries, partly due to release of NO This represents a new mechanism for control of human stem villous artery tone....

  19. Quasars Probing Quasars: the Circumgalactic Medium Surrounding z ~ 2 Quasars

    Science.gov (United States)

    Lau, Marie; Quasars Probing Quasars survey

    2018-01-01

    Understanding the circumgalactic medium--the gaseous halo surrounding a galaxy, is an integral part to understanding galaxy evolution. The z ~ 2-3 universe is interesting as this is when the star formation rate and AGN activity peak. My thesis concludes the decade-long Quasars Probing Quasars survey designed for studying massive galaxy formation and quasar feedback. I use background quasar sightlines that pass close to foreground quasars to study the circumgalactic medium of quasar-host galaxies in absorption. My sample of 149 quasar pairs involve spectra taken with 17 different optical and near IR instruments. I present results on the statistical and physical properties of the circumgalactic medium. The circumgalactic medium is enriched even beyond the virial radius. The alpha/Fe abundance ratio is enhanced, suggesting enrichment from core-collapse supernovae. The cool gas mass within the virial radius is enough to fuel star formation for another Gyr, and may account for 1/3 of the baryonic budget of the galaxy halo. The ionization state increases with projected distance from the quasar, which implies the quasar does not dominate the ionizing radiation flux. However, detection of fluorescent Lyman-alpha emission and NV absorption imply these transverse absorbers are partially illuminated by the quasar. In one peculiar case, the absorbing clump has density >100 cm^-3 and sub-parsec size. The average absorption in the circumgalactic medium exhibits large velocity widths, and is asymmetric about the systemic redshift of the galaxies. The widths are consistent with gravitational motions and Hubble flow, and outflows are not required to explain them. The asymmetry can be explained if the ionizing radiation from the quasar is anisotropic or intermittent and the gas is not in inflow. My results pose challenges for cosmological hydrodynamic simulations to produce a substantial cool gas reservoir surrounding quasars, that is also enriched and shows extreme kinematics.

  20. Bridge between fusion plasma and plasma processing

    International Nuclear Information System (INIS)

    Ohno, Noriyasu; Takamura, Shuichi

    2008-01-01

    In the present review, relationship between fusion plasma and processing plasma is discussed. From boundary-plasma studies in fusion devices new applications such as high-density plasma sources, erosion of graphite in a hydrogen plasma, formation of helium bubbles in high-melting-point metals and the use of toroidal plasmas for plasma processing are emerging. The authors would like to discuss a possibility of knowledge transfer from fusion plasmas to processing plasmas. (T. Ikehata)