WorldWideScience

Sample records for polar region upper

  1. A novel polarization interferometer for measuring upper atmospheric winds

    International Nuclear Information System (INIS)

    Ting-Kui, Mu; Chun-Min, Zhang

    2010-01-01

    A static polarization interferometer for measuring upper atmospheric winds is presented, based on two Savart plates with their optical axes perpendicular to each other. The principle and characteristics of the interferometer are described. The interferometer with a wide field of view can offer a stable benchmark optical path difference over a specified spectral region of 0.55–0.63 μm because there are no quarter wave plates. Since the instrument employs a straight line common-path configuration but without moving parts and slits, it is very compact, simple, inherently robust and has high throughput. The paper is limited to a theoretical analysis. (general)

  2. Upper Limit for Regional Sea Level Projections

    Science.gov (United States)

    Jevrejeva, Svetlana; Jackson, Luke; Riva, Riccardo; Grinsted, Aslak; Moore, John

    2016-04-01

    With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. With probabilistic approach we produce regional sea level projections taking into account large uncertainties associated with Greenland and Antarctica ice sheets contribution. We calculate the upper limit (as 95%) for regional sea level projections by 2100 with RCP8.5 scenario, suggesting that for the most coastlines upper limit will exceed the global upper limit of 1.8 m.

  3. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    Swift, D.L.

    1989-01-01

    During the report period significant progress on the quantitative understanding of regional upper airway deposition of airborne particle has been realized. Replicate models of the human upper airways obtained from post-mortem casting of the nasal, oral, pharyngeal, laryngeal and upper tracheal regions and in vivo magnetic resonance imaging (MRI) of the same regions of adults and children have been employed to determine the overall and local deposition characteristics of aerosols in the ultrafine (1--100 μm diameter) and fine (0.8--12 μm diameter) region. Studies have been carried out for both nasal and oral breathing during inspiratory and expiratory flow at constant flow rates representative of rest and states of exercise. The results of these investigations indicate that particles in the size range of ''unattached'' radon progeny (1--3 nm) are deposited in both the nasal and oral passages with high efficiency (60--80%) for both inspiration and expiration, with the nasal deposition being somewhat greater (5--10%) than oral deposition. The effect of flow rate on upper airway deposition for both pathways is not great; data analysis indicates that the deposition for all flow rates from 4--50 liters/minute can be grouped by plotting deposition vs Q- 1/8 , where Q is flow rate, a far weaker dependency than observed for inertial deposition. Diffusional transport is the primary mechanism of deposition, and size dependence can be accounted for by plotting, deposition percent vs D n where D is particle diffusion coefficient and n ranges from 0.5--0.66. 2 refs

  4. SeaWinds - Oceans, Land, Polar Regions

    Science.gov (United States)

    1999-01-01

    The SeaWinds scatterometer on the QuikScat satellite makes global radar measurements -- day and night, in clear sky and through clouds. The radar data over the oceans provide scientists and weather forecasters with information on surface wind speed and direction. Scientists also use the radar measurements directly to learn about changes in vegetation and ice extent over land and polar regions.This false-color image is based entirely on SeaWinds measurements obtained over oceans, land, and polar regions. Over the ocean, colors indicate wind speed with orange as the fastest wind speeds and blue as the slowest. White streamlines indicate the wind direction. The ocean winds in this image were measured by SeaWinds on September 20, 1999. The large storm in the Atlantic off the coast of Florida is Hurricane Gert. Tropical storm Harvey is evident as a high wind region in the Gulf of Mexico, while farther west in the Pacific is tropical storm Hilary. An extensive storm is also present in the South Atlantic Ocean near Antarctica.The land image was made from four days of SeaWinds data with the aid of a resolution enhancement algorithm developed by Dr. David Long at Brigham Young University. The lightest green areas correspond to the highest radar backscatter. Note the bright Amazon and Congo rainforests compared to the dark Sahara desert. The Amazon River is visible as a dark line running horizontally though the bright South American rain forest. Cities appear as bright spots on the images, especially in the U.S. and Europe.The image of Greenland and the north polar ice cap was generated from data acquired by SeaWinds on a single day. In the polar region portion of the image, white corresponds to the largest radar return, while purple is the lowest. The variations in color in Greenland and the polar ice cap reveal information about the ice and snow conditions present.NASA's Earth Science Enterprise is a long-term research and technology program designed to examine Earth

  5. PoSSUM: Polar Suborbital Science in the Upper Mesosphere

    Science.gov (United States)

    Reimuller, J. D.; Fritts, D. C.; Thomas, G. E.; Taylor, M. J.; Mitchell, S.; Lehmacher, G. A.; Watchorn, S. R.; Baumgarten, G.; Plane, J. M.

    2013-12-01

    Project PoSSUM (www.projectpossum.org) is a suborbital research project leveraging imaging and remote sensing techniques from Reusable Suborbital Launch Vehicles (rSLVs) to gather critical climate data through use of the PoSSUM Observatory and the PoSSUM Aeronomy Laboratory. An acronym for Polar Suborbital Science in the Upper Mesosphere, PoSSUM grew from the opportunity created by the Noctilucent Cloud Imagery and Tomography Experiment, selected by the NASA Flight Opportunities Program as Experiment 46-S in March 2012. This experiment will employ an rSLV (e.g. the XCOR Lynx Mark II) launched from a high-latitude spaceport (e.g. Eielson AFB, Alaska or Kiruna, Sweden) during a week-long deployment scheduled for July 2015 to address critical questions concerning noctilucent clouds (NLCs) through flights that transition the cloud layer where the clouds will be under direct illumination from the sun. The 2015 Project PoSSUM NLC campaign will use the unique capability of rSLVs to address key under-answered questions pertaining to NLCs. Specifically, PoSSUM will answer: 1) What are the small-scale dynamics of NLCs and what does this tell us about the energy and momentum deposition from the lower atmosphere? 2) What is the seasonal variability of NLCs, mesospheric dynamics, and temperatures? 3) Are structures observed in the OH layer coupled with NLC structures? 4) How do NLCs nucleate? and 5) What is the geometry of NLC particles and how do they stratify? Instrumentation will include video and still-frame visible cameras (PoSSUMCam), infrared cameras, a mesospheric temperatures experiment, a depolarization LiDAR, a mesospheric density and temperatures experiment (MCAT), a mesospheric winds experiment, and a meteoric smoke detector (MASS). The instrument suite used on PoSSUM will mature through subsequent campaigns to develop an integrated, modular laboratory (the ';PoSSUM Observatory') that will provide repeatable, low cost, in-situ NLC and aeronomy observations as well

  6. Anthropogenic Radionuglides in Marine Polar Regions

    Science.gov (United States)

    Holm, Elis

    The polar regions are important for the understanding of long range water and atmospheric transport of anthropogenic substances. Investigations show that atmospheric transport of anthropogenic radionuclides is the most important route of transport to the Antarctic while water transport plays a greater role for the Arctic. Fallout from nuclear detonation tests is the major source in the Antarctic while in the Arctic other sources, especially European reprocessing facilities, dominate for conservatively behaving rdionuclides such as 137Cs . The flux of 137Cs and 239+240Pu in the Antarctic is about 1/10 of that for the Arctic and the resulting concentrations in surface sea-water show the same ratio for the two areas. In the Antarctic concentration factors for 137Cs are higher than in the Arctic for similar species

  7. Electromagnetic energy deposition rate in the polar upper thermosphere derived from the EISCAT Svalbard radar and CUTLASS Finland radar observations

    Directory of Open Access Journals (Sweden)

    H. Fujiwara

    2007-11-01

    Full Text Available From simultaneous observations of the European incoherent scatter Svalbard radar (ESR and the Cooperative UK Twin Located Auroral Sounding System (CUTLASS Finland radar on 9 March 1999, we have derived the height distributions of the thermospheric heating rate at the F region height in association with electromagnetic energy inputs into the dayside polar cap/cusp region. The ESR and CUTLASS radar observations provide the ionospheric parameters with fine time-resolutions of a few minutes. Although the geomagnetic activity was rather moderate (Kp=3+~4, the electric field obtained from the ESR data sometimes shows values exceeding 40 mV/m. The estimated passive energy deposition rates are also larger than 150 W/kg in the upper thermosphere over the ESR site during the period of the enhanced electric field. In addition, enhancements of the Pedersen conductivity also contribute to heating the upper thermosphere, while there is only a small contribution for thermospheric heating from the direct particle heating due to soft particle precipitation in the dayside polar cap/cusp region. In the same period, the CUTLASS observations of the ion drift show the signature of poleward moving pulsed ionospheric flows with a recurrence rate of about 10–20 min. The estimated electromagnetic energy deposition rate shows the existence of the strong heat source in the dayside polar cap/cusp region of the upper thermosphere in association with the dayside magnetospheric phenomena of reconnections and flux transfer events.

  8. Electromagnetic energy deposition rate in the polar upper thermosphere derived from the EISCAT Svalbard radar and CUTLASS Finland radar observations

    Directory of Open Access Journals (Sweden)

    H. Fujiwara

    2007-11-01

    Full Text Available From simultaneous observations of the European incoherent scatter Svalbard radar (ESR and the Cooperative UK Twin Located Auroral Sounding System (CUTLASS Finland radar on 9 March 1999, we have derived the height distributions of the thermospheric heating rate at the F region height in association with electromagnetic energy inputs into the dayside polar cap/cusp region. The ESR and CUTLASS radar observations provide the ionospheric parameters with fine time-resolutions of a few minutes. Although the geomagnetic activity was rather moderate (Kp=3+~4, the electric field obtained from the ESR data sometimes shows values exceeding 40 mV/m. The estimated passive energy deposition rates are also larger than 150 W/kg in the upper thermosphere over the ESR site during the period of the enhanced electric field. In addition, enhancements of the Pedersen conductivity also contribute to heating the upper thermosphere, while there is only a small contribution for thermospheric heating from the direct particle heating due to soft particle precipitation in the dayside polar cap/cusp region. In the same period, the CUTLASS observations of the ion drift show the signature of poleward moving pulsed ionospheric flows with a recurrence rate of about 10–20 min. The estimated electromagnetic energy deposition rate shows the existence of the strong heat source in the dayside polar cap/cusp region of the upper thermosphere in association with the dayside magnetospheric phenomena of reconnections and flux transfer events.

  9. Environmental impact on the polar regions

    International Nuclear Information System (INIS)

    Jaffe, D.A.; Leighton, E.; Tumeo, M.A.

    1994-01-01

    The remote and frigid polar regions are no longer isolated from the activities, pollutants, and controversies that bedevil their more temperate neighbors, say three researchers at the University of Alaska in Fairbanks. For example, Daniel A. Jaffe, Elizabeth Leighton, and Mark A. Tumeo point to traces of DDT, PCBs, and heavy metals that routinely turn up in arctic marine mammals and to the ozone hole over the Antarctic. While similar in environmental makeup, the arctic and Antarctic are poles apart in their political structure and, thus, in their environmental exposure, the researchers note. The Antarctic is managed under a long-standing international treaty, while the arctic is sovereign territory to eight separate nations. The international treaty sets aside the Antarctic for peaceful scientific research within strict environmental boundaries. It bans both military activity and minerals extraction-the two activities that have caused the most damage in the arctic. The main threats to Antarctica's environment come from the intrusion of major scientific research operations and the growing tourism industry. On the other hand, the arctic suffered from the massive Cold War military buildup by both the United States and the former Soviet Union. The environmental residue from that buildup is only now being revealed, the authors say. Major oil and gas drilling and coal and metal-ore mining also have taken a huge environmental toll, they add

  10. An assessment of ten ocean reanalyses in the polar regions

    Science.gov (United States)

    Uotila, Petteri

    2017-04-01

    Ocean reanalysis (ORA) combines observations either statistically or with a hydrodynamical model, to reconstruct historical changes in the ocean. Global and regional ORA products are increasingly used in polar research, but their quality remains to be systematically assessed. To address this, the Polar ORA Intercomparison Project (PORA-IP) has been established following on from the ORA-IP project (Balmaseda et al. 2015, with other papers in a special issue of Climate Dynamics). The PORA-IP is constituted under the COST EOS initiative with plans to review reanalyses products in both the Arctic and Antarctic, and is endorsed by YOPP - the Year of Polar Prediction project. Currently, the PORA-IP team consists of 21 researchers from 15 institutes and universities. The ORA-IP products with polar physics, such as sea ice, have been updated where necessary and collected in a public database. In addition to model output, available observational polar climatologies are collected and used in the assessments. Due to the extensive variety of products, this database should become a valuable resource outside the PORA-IP community. For a comprehensive evaluation of the ten ORA products (CGLORSv5, ECDA3.1, GECCO2, Glorys2v4, GloSea5_GO5, MOVEG2i, ORAP5, SODA3.3.1, TOPAZ4 and UR025.4) in the Arctic and Southern Oceans several specific diagnostics are assessed. The PORA-IP diagnostics target the following topics: hydrography; heat, salinity and freshwater content; ocean transports and surface currents; mixed layer depth; sea-ice concentration and thickness; and snow thickness over sea ice. Based on these diagnostics, ORA product biases against observed data and their mutual spread are quantified, and possible reasons for discrepancies discussed. So far, we have identified product outliers and evaluated the multi-model mean. We have identified the importance of the atmospheric forcing, air-ocean coupling protocol and sea-ice data assimilation for the product performance. Moreover, we

  11. Adapting the HSV polarization-color mapping for regions with low irradiance and high polarization.

    Science.gov (United States)

    Scott Tyo, J; Ratliff, Bradley M; Alenin, Andrey S

    2016-10-15

    Many mappings from polarization into color have been developed so that polarization information can be displayed. One of the most common of these maps the angle of linear polarization into color hue and degree of linear polarization into color saturation, while preserving the irradiance information from the polarization data. While this strategy enjoys wide popularity, there is a large class of polarization images for which it is not ideal. It is common to have images where the strongest polarization signatures (in terms of degree of polarization) occur in regions of relatively low irradiance: either in shadow in reflective bands or in cold regions in emissive bands. Since the irradiance is low, the chromatic properties of the resulting images are generally not apparent. Here we present an alternate mapping that uses the statistics of the angle of polarization as a measure of confidence in the polarization signature, then amplifies the irradiance in regions of high confidence, and leaves it unchanged in regions of low confidence. Results are shown from an LWIR and a visible spectrum imager.

  12. Regionalization of the Upper Tana Basin of Kenya Using Stream ...

    African Journals Online (AJOL)

    Regionalization of the Upper Tana Basin of Kenya Using Stream Flow Records. ... river gauge stations in the basin using the empirical orthogonal function analysis ... the study basin to be grouped into four homogenous hydrological zones that ...

  13. Regional aerosol deposition in human upper airways

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D.L.

    1991-11-01

    During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po{sup 218} particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po{sup 218} particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po{sup 218} particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.

  14. Regional aerosol deposition in human upper airways

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D.L.

    1992-11-01

    Laboratory experimental studies were carried out to investigate the factors influencing the deposition of aerosols ranging in size from 1 nm to 10 [mu]m in the human nasal, oral, pharyngeal and laryngeal airways. These experimental studies were performed in replicate upper airway physical models and in human volunteer subjects. New replicate models of the oral passage of an infant, the oral passage of an adult at two openings and the combined nasal and oral airways of an adult were constructed during the period, adding to the existing models of adult, child and infant nasal and oral airways models. Deposition studies in the adult oral and adult nasal models were performed under simulated cyclic flow conditions with 1 nm particles to compare with previously measured constant flow studies. Similar studies with inertial particles (1--10 [mu]m diameter) were performed with the adult nasal model; in both instances, results with cyclic flow were similar to constant flow results using a simple average flow rate based on inspiratory volume and time of inspiration. Human subject studies were performed with particle sizes 5--20 nm for nasal inspiration; preliminary analysis shows good agreement with model studies at several representative flow rates. Nasal inspiratory inertial deposition of 1--4 [mu]m diameter particles was measured in several adults as a function of airway dimensions; dimensional changes of the valve area by decongestion did not produce concomitant deposition changes.

  15. Regional aerosol deposition in human upper airways

    International Nuclear Information System (INIS)

    Swift, D.L.

    1991-01-01

    During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po 218 particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po 218 particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po 218 particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig

  16. Hydrogen Distribution in the Lunar Polar Regions

    Science.gov (United States)

    Sanin, A. B.; Mitrofanov, I. G.; Litvak, M. L.; Bakhtin, B. N.; Bodnarik, J. G.; Boynton, W. V.; Chin, G.; Evans, L. G.; Harshmann, K.; Fedosov, F.; hide

    2016-01-01

    We present a method of conversion of the lunar neutron counting rate measured by the Lunar Reconnaissance Orbiter (LRO) Lunar Exploration Neutron Detector (LEND) instrument collimated neutron detectors, to water equivalent hydrogen (WEH) in the top approximately 1 m layer of lunar regolith. Polar maps of the Moon’s inferred hydrogen abundance are presented and discussed.

  17. A consistent definition of the Arctic polar vortex breakup in both the lower and upper stratosphere

    Science.gov (United States)

    Choi, W.; Seo, J.

    2014-12-01

    Breakup of the polar vortex is a dominant feature of the seasonal transition from winter to summer in the stratosphere, which significantly affects stratospheric O3 concentration and tropospheric weather. Previously several criteria for the vortex breakup have been suggested based on the potential vorticity (PV) and wind speed, however, those mainly have focused on the lower stratospheric vortex of which spatiotemporal evolution and decay are more continuous than those of the upper stratospheric vortex. To find a consistent criterion for the vortex breakup in both the lower and upper stratosphere, the present study defined a polar vortex breakup day as when PV gradient at the polar vortex edge becomes lower than that at the subtropical edge on the area equivalent latitude based on PV. With applying the new definition to the UK Met Office reanalysis data, the breakup days of the Arctic polar vortices on 18 isentropic levels from 450 K to 1300 K were calculated for the period of 1993-2005. In comparison with CH4, N2O and O3 measured by the ILAS and POAM II/III satellite instruments, the breakup days are well consistent with changes in the distribution of such tracers as well as their zonal standard deviations associated with the vortex structure breaking and irreversible mixing. The vortex breakup in the upper stratosphere occurs more or less a month prior to that in the middle and lower stratosphere while the stratospheric final warming events occurs simultaneously in the upper and lower stratosphere.

  18. Polarization images of the inner regions of Comet Halley

    International Nuclear Information System (INIS)

    Eaton, N.; Scarrott, S.M.; Warren-Smith, R.F.

    1988-01-01

    The present CCD polarimeter images of intensity and polarization within the near-nucleus regions of Comet Halley show the occurrence of dust jets on two days in January, 1986, which exhibit increased polarizations above the level of the surrounding coma. Three possible reasons for the enhanced polarization in the jets are considered, assuming that the polarization increase is due to dust grains: (1) the size distribution of the grains could be different from the surrounding coma; (2) the material of the grains could have a different refractive index; and (3) the ratio of dust to gas emission could be different in the jets. 13 references

  19. Advancing Environmental Prediction Capabilities for the Polar Regions and Beyond during The Year of Polar Prediction

    Science.gov (United States)

    Werner, Kirstin; Goessling, Helge; Hoke, Winfried; Kirchhoff, Katharina; Jung, Thomas

    2017-04-01

    Environmental changes in polar regions open up new opportunities for economic and societal operations such as vessel traffic related to scientific, fishery and tourism activities, and in the case of the Arctic also enhanced resource development. The availability of current and accurate weather and environmental information and forecasts will therefore play an increasingly important role in aiding risk reduction and safety management around the poles. The Year of Polar Prediction (YOPP) has been established by the World Meteorological Organization's World Weather Research Programme as the key activity of the ten-year Polar Prediction Project (PPP; see more on www.polarprediction.net). YOPP is an internationally coordinated initiative to significantly advance our environmental prediction capabilities for the polar regions and beyond, supporting improved weather and climate services. Scheduled to take place from mid-2017 to mid-2019, the YOPP core phase covers an extended period of intensive observing, modelling, prediction, verification, user-engagement and education activities in the Arctic and Antarctic, on a wide range of time scales from hours to seasons. The Year of Polar Prediction will entail periods of enhanced observational and modelling campaigns in both polar regions. With the purpose to close the gaps in the conventional polar observing systems in regions where the observation network is sparse, routine observations will be enhanced during Special Observing Periods for an extended period of time (several weeks) during YOPP. This will allow carrying out subsequent forecasting system experiments aimed at optimizing observing systems in the polar regions and providing insight into the impact of better polar observations on forecast skills in lower latitudes. With various activities and the involvement of a wide range of stakeholders, YOPP will contribute to the knowledge base needed to managing the opportunities and risks that come with polar climate change.

  20. Atmospheric Modeling of the Martian Polar Regions: CRISM EPF Coverage During the South Polar Spring Recession

    Science.gov (United States)

    Brown, A. J.; McGuire, P.; Wolff, M. J.

    2008-03-01

    We describe efforts to model dust and ice aerosols content and soils and icy surface reflectance in the Martian southern polar region during spring recession (Ls = 152-320) using CRISM emission phase function (EPF) observations.

  1. IS THE POLAR REGION DIFFERENT FROM THE QUIET REGION OF THE SUN?

    International Nuclear Information System (INIS)

    Ito, Hiroaki; Shiota, Daikou; Tokumaru, Munetoshi; Fujiki, Ken'ichi; Tsuneta, Saku

    2010-01-01

    Observations of the polar region of the Sun are critically important for understanding the solar dynamo and the acceleration of solar wind. We carried out precise magnetic observations on both the north polar region and the quiet Sun at the east limb with the spectropolarimeter of the Solar Optical Telescope aboard Hinode to characterize the polar region with respect to the quiet Sun. The average area and the total magnetic flux of the kilo-Gauss magnetic concentrations in the polar region appear to be larger than those of the quiet Sun. The magnetic field vectors classified as vertical in the quiet Sun have symmetric histograms around zero in the strengths, showing balanced positive and negative fluxes, while the histogram in the north polar region is clearly asymmetric, showing a predominance of the negative polarity. The total magnetic flux of the polar region is larger than that of the quiet Sun. In contrast, the histogram of the horizontal magnetic fields is exactly the same for both the polar region and the quiet Sun. This is consistent with the idea that a local dynamo process is responsible for the horizontal magnetic fields. A high-resolution potential field extrapolation shows that the majority of magnetic field lines from the kG-patches in the polar region are open with a fanning-out structure very low in the atmosphere, while in the quiet Sun, almost all the field lines are closed.

  2. Mapping Irrigation Potential in the Upper East Region of Ghana

    Science.gov (United States)

    Akomeah, E.; Odai, S. N.; Annor, F. O.; Adjei, K. A.; Barry, B.

    2009-04-01

    The Upper East Region together with the other two regions in Northern Ghana (Upper West and Northern Region) is seen as the locus of perennial food deficit (GPRS, 2003). Despite, the provision of over 200 small scale dams and various mechanisms aimed at poverty alleviation, the region is still plagued with poverty and yearly food shortages. To achieve food security and alleviate poverty in the region however, modernization of agriculture through irrigation is deemed inevitable. While it is true that considerable potential still exists for future expansion of irrigation, it cannot be refuted that water is becoming scarcer in the regions where the need for irrigation is most important, hence mapping the irrigation potential of the region will be the first step toward ensuring sound planning and sustainability of the irrigation developments. In this study, an attempt has been made to map out the irrigation potential of the Upper East Region. The river basin approach was used in assessing the irrigation potential. The catchments drained by The White Volta river, Red volta river, River Sissili and River Kulpawn were considered in the assessment. The irrigation potential for the sub basins was computed by combining information on gross irrigation water requirements for the selected cash crops, area of soil suitable for irrigation and available water resources. The capacity of 80%, 70%, 60% and 50% time of exceedance flow of the available surface water resources in the respective sub basins was estimated. The area that can be irrigated with this flow was computed with selected cropping pattern. Combining the results of the potential irrigable areas and the land use map of the respective sub basins, an irrigation potential map has been generated showing potential sites in the upper east region that can be brought under irrigation. Keywords: Irrigation potential, irrigation water requirement, land evaluation, dependable flow

  3. PERSPECTIVE: Snow matters in the polar regions

    Science.gov (United States)

    Sodeau, John

    2010-03-01

    Antarctica is not quite as chemically pristine as might sometimes be thought (Jones et al 2008). For example, as elsewhere, reduced sulfur species such as dimethylsulfide (DMS) are emitted from biogenic marine sources at the poles (Read et al 2008). Somewhat less well known is that inland (as opposed to coastal) field campaigns have also detected, within the Antarctic boundary layer (ABL), emissions containing unexpectedly high levels of diverse, oxidizing chemicals such as NOx, nitrate ions, formaldehyde, ozone and hydrogen peroxide (Honrath et al 1999, Hutterli et al 2004, Sumner and Shepson 1999). And then there are the halogen-containing compounds (Simpson et al 2007). The transformation of DMS to sulfate aerosols capable of acting as cloud condensation nuclei often proceeds via one main oxidized product of DMS, namely methanesulfonic acid (MSA). Two specific reactions have been well studied to date in this regard, namely DMS plus either OH or NO3 radicals. Corresponding reactions with halogen radicals, which also contribute to the oxidizing capacity of our atmosphere, have generally been considered to be of less importance. The reason for this view is that even though the reactivity of bromine- and iodine-containing radicals is much greater than that of OH, the halogens were thought to be relatively scarce in the polar atmosphere. However both BrO (and IO) have been detected in the Antarctic CHABLIS campaign, as discussed in depth in the Atmospheric Chemistry and Physics special issue of 2008, see Jones et al (2008). It was subsequently shown that calculated MSA production from the DMS/BrO reaction may be about an order of magnitude greater than when the OH radical was the oxidizing reactant. The recent analytical measurements by Antony et al (2010) of MSA, Br and NO3 found in snow along the Ingrid Christensen Coast of East Antarctica are important in the above field context. Hence it would appear that the concentrations of these ions in ice-cap sites are up

  4. People, soil and manioc interactions in the upper Amazon region

    NARCIS (Netherlands)

    Peña Venegas, C.P.

    2015-01-01

    Abstract

    Clara Patricia Peña Venegas (2015). People, soil and manioc interactions in the upper Amazon region. PhD thesis, Wageningen University, The Netherlands, with summaries in English and Dutch, 210 pp.

    The presence of anthropogenic soils, or Amazonian Dark

  5. Wildlife in the Upper Great Lakes Region: a community profile.

    Science.gov (United States)

    Janine M. Benyus; Richard R. Buech; Mark D. Nelson

    1992-01-01

    Wildlife habitat data from seven Great Lakes National Forests were combined into a wildlife-habitat matrix named NORTHWOODS. The composite NORTHWOODS data base is summarized. Multiple queries of NORTHWOODS were used to profile the wildlife community of the Upper Great Lakes region.

  6. CLIMATIC JUMP IN THE POLAR REGION (I)

    OpenAIRE

    ヤマモト, リョウザブロウ; イワシマ, タツヤ; ホシアイ, マコト; Ryozaburo, YAMAMOTO; Tatsuya, IWASHIMA; Makoto, HOSHIAI

    1987-01-01

    From the analysis of the climatic elements over Japan, we can detect the "climatic jumps" around the years 1920 and 1950,which is a new concept in the climatic diagnosis proposed by the present authors (R. YAMAMOTO et al. : J. Meteorol. Soc. Jpn., 63,1157,1985,64,273,1986). Taking account of several results which show the simultaneous occurrence of the climatic jumps of the surface air temperature, precipitation, etc., in the other regions by the other investigators, we may infer the "climati...

  7. Regional polarization sensitivity of articular cartilage by using polarization sensitive optical coherence tomography

    Science.gov (United States)

    Xie, Tuqiang; Guo, Shuguang; Chen, Zhongping; Peavy, George M.

    2007-02-01

    In this study, PS-OCT is used to image fresh bovine joints to investigate the orientation of collagen fibrils in relation to optical phase retardation to better understand the distribution of normal matrix orientation and articular cartilage birefringence in different regions of a whole joint. Understanding and mapping variations in matrix organization and orientation within the normal joint is an important issue in potential applications of PS-OCT for evaluation and diagnosis of degenerative joint disease (DJD). The experimental results demonstrate that articular cartilage is not polarization sensitive on the edge of the medial, but polarization sensitive on the lateral edge of the tibial plateau. The collagen orientation on the edge of the joint is different from the central areas of the joint. Normal articular cartilage demonstrates regional polarization sensitivity within joints that is important to understand in order to accurately assess cartilage health by PS-OCT.

  8. Mars: Stratigraphy of Western Highlands and Polar Regions

    Science.gov (United States)

    Tanaka, K. L.; Scott, D. H.; Tuesink, M. F.

    1985-01-01

    Geologic mapping and stratigraphic studies of Mars based on Viking images improved knowledge of the relative age and occurrence of geologic units on a global scale. Densities of geologic units or features during the Noarchian, Hesperian, and Amazonian periods are indicated for the North and South polar regions as well as the equatorial region of Mars. Cumulative counts of crater size frequencies for craters larger than 2 km in diameter on plateau units mapped in the western region of Mars counts indicate that the plateau terrain as a whole was thinly resurfaced during the Hesperian Period, and a large proportion of pre-existing craters less than 10 to 15 km in diameter was buried. The formation of northern plains, subpolar highlands, and both polar regions is also described.

  9. Stratigraphy of the south polar region of Ganymede

    Science.gov (United States)

    Dehon, R. A.

    1987-01-01

    A preliminary assessment is made of the stratigraphy and geology in the south polar region of the Jovian satellite, Ganymede. Geologic mapping is based on inspection of Voyager images and compilation on an airbrush base map at a scale of 1:5M. Illumination and resolution vary greatly in the region. Approximately half of the quadripole is beyond the terminator. Low angle illumination over a large part of the area precludes distinction of some units by albedo characteristics. Several types of grooved terrain and groove related terrain occur in the southern polar region. Grooves typically occur in straight to curvilinear sets or lanes. Bright lanes and grooved lanes intersect at high angles outlining polygons of dark cratered terrain. Groove sets exhibit a range of ages as shown by superposition or truncation and by crater superposition ages.

  10. Demographic characteristics of MS patients in Poland's upper Silesia region.

    Science.gov (United States)

    Pierzchala, Krystyna; Adamczyk-Sowa, Monika; Dobrakowski, Pawel; Kubicka-Baczyk, Katarzyna; Niedziela, Natalia; Sowa, Pawel

    2015-05-01

    In Poland, no national registry of MS patients has yet been introduced. So far, no demographic studies have been conducted in patients with MS in Upper Silesia. The aim of the present study was to evaluate, for the first time, a selected demographic and clinical parameters in MS patients from the Upper Silesia region and compare these characteristics with previously published data from other regions of Poland. 640 patients with clinically defined MS, were prospectively and randomly selected for the study. Social, socio-economic, and demographic data were obtained through a questionnaire study. All subjects performed a self-assessment of their health condition using EQ-5D and EQ-VAS version questionnaires. The ratio of women to men was 2.18. The average age of onset was 29.6 ± 11.1 years; the disease duration was 7.9 ± 4.5 years. The relapsing-remitting form of MS was diagnosed in 73.12%. In 71.25% the onset was monofocal and in 28.75% multifocal disease onset was observed. Among the studied population 339 (52.97%) patients were still employed. A mean EQ-VAS score of 66.11 ± 20.12 was calculated. Results from our study identify for the first time the demographic and clinical characteristics of the Upper Silesia MS population.

  11. Illumination Conditions of the Lunar Polar Regions Using LOLA Topography

    Science.gov (United States)

    Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.; Torrence, M. H.

    2011-01-01

    We use high-resolution altimetry data obtained by the Lunar Orbiter Laser Altimeter instrument onboard the Lunar Reconnaissance Orbiter to characterize present illumination conditions in the polar regions of the Moon. Compared to previous studies, both the spatial and temporal extent of the simulations are increased significantly, as well as the coverage (fill ratio) of the topographic maps used, thanks to the 28 Hz firing rate of the five-beam instrument. We determine the horizon elevation in a number of directions based on 240 m-resolution polar digital elevation models reaching down to 75 latitude. The illumination of both polar regions extending to 80 can be calculated for any geometry from those horizon longitudinal profiles. We validated our modeling with recent Lunar Reconnaissance Orbiter Wide-Angle Camera images. We assessed the extent of permanently shadowed regions (PSRs, defined as areas that never receive direct solar illumination), and obtained total areas generally larger than previous studies (12,866 and 16,055 km2, in the north and south respectively). We extended our direct illumination model to account for singly-scattered light, and found that every PSR does receive some amount of scattered light during the year. We conducted simulations over long periods (several 18.6-years lunar precession cycles) with a high temporal resolution (6 h), and identified the most illuminated locations in the vicinity of both poles. Because of the importance of those sites for exploration and engineering considerations, we characterized their illumination more precisely over the near future. Every year, a location near the Shackleton crater rim in the south polar region is sunlit continuously for 240 days, and its longest continuous period in total darkness is about 1.5 days. For some locations small height gains ( 10 m) can dramatically improve their average illumination and reduce the night duration, rendering some of those particularly attractive energy-wise as

  12. Lithofacies palaeogeography of the Upper Permian Changxing Stage in the Middle and Upper Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    He Youbin

    2013-04-01

    Full Text Available Based on the petrological study, according to single factor analysis and multifactor comprehensive mapping method, the quantitative lithofacies palaeogeography of the Upper Permian Changxing Stage of the Middle and Upper Yangtze Region was studied. The Changxing Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks; in addition, clastic and siliceous rocks occur with rare coals and pyroclastic rocks. Lithofacies can be divided into five types, including clastic rock assemblage, clastic rock–limestone assemblage, limestone assemblage, limestone–siliceous rock assemblage, and siliceous rock–clastic rock assemblage. Four fundamental ecological types and five fossil assemblages were recognized in the Changxing Stage. On the basis of the petrological and palaeoecological study, eight single factors were chosen including thickness, content of marine rocks, content of shallow water carbonate rocks, content of bioclasts with limemud matrix, content of bioclasts with sparry cement, distribution of reefs, content of thin bedded siliceous rocks and content of deep water sedimentary rocks. And eight single factor maps and one lithofacies paleogeographic map of the Changxing Stage were compiled. Paleoenvironments from west to east include an erosional area, fluvial plain, clastic platform, carbonate platform and reefs that developed there, slope and basin, low energy organic banks, and high energy organic banks. Sedimentary environments have an obvious control on the development of the source rocks, and the excellent source rocks are developed in the Dalong Formation. Changxing Stage reservoirs should be dominated by the reef and platform surrounding the Guangyuan–Liangping Basin rim area, and is the most favorable exploration area of the reef petroleum reservoirs of the Changxing Formation.

  13. Effects of the racket polar moment of inertia on dominant upper limb joint moments during tennis serve.

    Directory of Open Access Journals (Sweden)

    Isabelle Rogowski

    Full Text Available This study examined the effect of the polar moment of inertia of a tennis racket on upper limb loading in the serve. Eight amateur competition tennis players performed two sets of 10 serves using two rackets identical in mass, position of center of mass and moments of inertia other than the polar moment of inertia (0.00152 vs 0.00197 kg.m2. An eight-camera motion analysis system collected the 3D trajectories of 16 markers, located on the thorax, upper limbs and racket, from which shoulder, elbow and wrist net joint moments and powers were computed using inverse dynamics. During the cocking phase, increased racket polar moment of inertia was associated with significant increases in the peak shoulder extension and abduction moments, as well the peak elbow extension, valgus and supination moments. During the forward swing phase, peak wrist extension and radial deviation moments significantly increased with polar moment of inertia. During the follow-through phase, the peak shoulder adduction, elbow pronation and wrist external rotation moments displayed a significant inverse relationship with polar moment of inertia. During the forward swing, the magnitudes of negative joint power at the elbow and wrist were significantly larger when players served using the racket with a higher polar moment of inertia. Although a larger polar of inertia allows players to better tolerate off-center impacts, it also appears to place additional loads on the upper extremity when serving and may therefore increase injury risk in tennis players.

  14. Effects of the racket polar moment of inertia on dominant upper limb joint moments during tennis serve.

    Science.gov (United States)

    Rogowski, Isabelle; Creveaux, Thomas; Chèze, Laurence; Macé, Pierre; Dumas, Raphaël

    2014-01-01

    This study examined the effect of the polar moment of inertia of a tennis racket on upper limb loading in the serve. Eight amateur competition tennis players performed two sets of 10 serves using two rackets identical in mass, position of center of mass and moments of inertia other than the polar moment of inertia (0.00152 vs 0.00197 kg.m2). An eight-camera motion analysis system collected the 3D trajectories of 16 markers, located on the thorax, upper limbs and racket, from which shoulder, elbow and wrist net joint moments and powers were computed using inverse dynamics. During the cocking phase, increased racket polar moment of inertia was associated with significant increases in the peak shoulder extension and abduction moments, as well the peak elbow extension, valgus and supination moments. During the forward swing phase, peak wrist extension and radial deviation moments significantly increased with polar moment of inertia. During the follow-through phase, the peak shoulder adduction, elbow pronation and wrist external rotation moments displayed a significant inverse relationship with polar moment of inertia. During the forward swing, the magnitudes of negative joint power at the elbow and wrist were significantly larger when players served using the racket with a higher polar moment of inertia. Although a larger polar of inertia allows players to better tolerate off-center impacts, it also appears to place additional loads on the upper extremity when serving and may therefore increase injury risk in tennis players.

  15. At site and regional analysis of maximum annual and seasonal discharges and precipitation depths in the upper Hron region

    International Nuclear Information System (INIS)

    Kohnova, S.; Hlavcova, K.

    2004-01-01

    In this presentation authors deal with the regional analysis of maximum annual and seasonal discharges and precipitation depths in the upper Hron region (Slovak Republic). This work has two objectives: (1) At site and regional analysis of annual and seasonal maximum design discharges in the upper Hron region; (2) Analysis of annual and seasonal maximum design precipitations in the connection of extreme runoff condition in the upper Hron region

  16. Transient surface liquid in Titan's south polar region from Cassini

    Science.gov (United States)

    Hayes, A.G.; Aharonson, O.; Lunine, J.I.; Kirk, R.L.; Zebker, H.A.; Wye, L.C.; Lorenz, R.D.; Turtle, E.P.; Paillou, P.; Mitri, Giuseppe; Wall, S.D.; Stofan, E.R.; Mitchell, K.L.; Elachi, C.

    2011-01-01

    Cassini RADAR images of Titan's south polar region acquired during southern summer contain lake features which disappear between observations. These features show a tenfold increases in backscatter cross-section between images acquired one year apart, which is inconsistent with common scattering models without invoking temporal variability. The morphologic boundaries are transient, further supporting changes in lake level. These observations are consistent with the exposure of diffusely scattering lakebeds that were previously hidden by an attenuating liquid medium. We use a two-layer model to explain backscatter variations and estimate a drop in liquid depth of approximately 1-m-per-year. On larger scales, we observe shoreline recession between ISS and RADAR images of Ontario Lacus, the largest lake in Titan's south polar region. The recession, occurring between June 2005 and July 2009, is inversely proportional to slopes estimated from altimetric profiles and the exponential decay of near-shore backscatter, consistent with a uniform reduction of 4 ± 1.3 m in lake depth. Of the potential explanations for observed surface changes, we favor evaporation and infiltration. The disappearance of dark features and the recession of Ontario's shoreline represents volatile transport in an active methane-based hydrologic cycle. Observed loss rates are compared and shown to be consistent with available global circulation models. To date, no unambiguous changes in lake level have been observed between repeat images in the north polar region, although further investigation is warranted. These observations constrain volatile flux rates in Titan's hydrologic system and demonstrate that the surface plays an active role in its evolution. Constraining these seasonal changes represents the first step toward our understanding of longer climate cycles that may determine liquid distribution on Titan over orbital time periods.

  17. DVCS in the fragmentation region of polarized electron

    International Nuclear Information System (INIS)

    Akushevich, I.; Kuraev, E.A.; Nikolaev, N.N.

    2000-01-01

    For the kinematical region when a hard photon is emitted predominantly close to the direction of motion of a longitudinally polarized initial electron and relatively small momentum transfer to a proton we calculate the azimuthal asymmetry of a photon emission. It arises from the interference of the Bethe-Heitler amplitude and those which are described by a heavy photon impact factor. The azimuthal asymmetry does not decrease in the limit of infinite cms energy. The lowest order expression for the impact factor of a heavy photon is presented

  18. Cloud Statistics and Discrimination in the Polar Regions

    Science.gov (United States)

    Chan, M.; Comiso, J. C.

    2012-12-01

    Despite their important role in the climate system, cloud cover and their statistics are poorly known, especially in the polar regions, where clouds are difficult to discriminate from snow covered surfaces. The advent of the A-train, which included Aqua/MODIS, CALIPSO/CALIOP and CloudSat/CPR sensors has provided an opportunity to improve our ability to accurately characterize the cloud cover. MODIS provides global coverage at a relatively good temporal and spatial resolution while CALIOP and CPR provide limited nadir sampling but accurate characterization of the vertical structure and phase of the cloud cover. Over the polar regions, cloud detection from a passive sensors like MODIS is challenging because of the presence of cold and highly reflective surfaces such as snow, sea-ice, glaciers, and ice-sheet, which have surface signatures similar to those of clouds. On the other hand, active sensors such as CALIOP and CPR are not only very sensitive to the presence of clouds but can also provide information about its microphysical characteristics. However, these nadir-looking sensors have sparse spatial coverage and their global data can have data spatial gaps of up to 100 km. We developed a polar cloud detection system for MODIS that is trained using collocated data from CALIOP and CPR. In particular, we employ a machine learning system that reads the radiative profile observed by MODIS and determine whether the field of view is cloudy or clear. Results have shown that the improved cloud detection scheme performs better than typical cloud mask algorithms using a validation data set not used for training. A one-year data set was generated and results indicate that daytime cloud detection accuracies improved from 80.1% to 92.6% (over sea-ice) and 71.2% to 87.4% (over ice-sheet) with CALIOP data used as the baseline. Significant improvements are also observed during nighttime, where cloud detection accuracies increase by 19.8% (over sea-ice) and 11.6% (over ice

  19. Radiative Forcing from Emissivity Response in Polar Regions

    Science.gov (United States)

    Kuo, C.; Feldman, D.; Huang, X.; Flanner, M.; Chen, X.; Yang, P.; Kuo, C.

    2016-12-01

    A detailed assessment of the radiative balance and its controlling factors in polar regions is a critical prerequisite for understanding and predicting the polar amplification of climate change. Accordingly, we investigate the role of infrared surface emissivity in polar regions as a potential feedback mechanism following Feldman et al, 2014. In this work, we investigate the climatic response of the Community Earth System Model (CESM) with spectral emissivity values that are implemented in a physically consistent manner for non-vegetated surfaces. In a control model run where 1850 CO2 volume mixing ratio (vmr) is fixed, the updated spectral emissivity values are imposed for modified surface boundary conditions in the atmospheric model component. Climatic stability in the emergent globally averaged surface temperature is observed on decadal scales for an unforced (control) run. Analytic kernels representing the change in top of the atmosphere OLR given changes in emissivity are calculated on-line during the model runs, incorporating spatially and temporally varied humidity profiles impactful to transmission. Globally averaged kernels of the sensitivity of OLR to surface emissivity calculated for control and ramped CO2 runs exhibit temporal evolution with statistically significant differences in shape. Additionally, kernel and spectrally-averaged emissivity differences between monthly-averaged maps of control and ramped runs demonstrate a seasonal cycle. Similar to the treatment of cryosphere radiative forcing in Flanner et al, 2011, we define emissivity response as the product of the emissivity kernel and the change in month-to-month emissivity. At the end of 20th century, the 10-year emissivity forcing averaged at latitudes > 60°, is found to be negative (positive) in January (July), due to increasing (decreasing) sea-ice. These findings indicate that differences in surface emissivity between frozen and unfrozen surfaces decrease wintertime and increase summertime

  20. 40 CFR 81.55 - Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Northeast Pennsylvania-Upper Delaware... Designation of Air Quality Control Regions § 81.55 Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control Region. The Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control...

  1. Crust and upper mantle structure in the Caribbean region by group velocity tomography and regionalization

    International Nuclear Information System (INIS)

    O'Leary, Gonzalez; Alvarez, L.; Chimera, G.; Panza, G.F.

    2004-04-01

    An overview of the crust and upper mantle structure of the Central America and Caribbean region is presented as a result of the processing of more than 200 seismograms recorded by digital broadband stations from SSSN and GSN seismic networks. By FTAN analysis of the fundamental mode of the Rayleigh waves, group velocity dispersion curves are obtained in the period range from 10 s to 40 s; the error of these measurements varies from 0.06 and 0.10 km/s. From the dispersion curves, seven tomographic maps at different periods and with average spatial resolution of 500 km are obtained. Using the logical combinatorial classification techniques, eight main groups of dispersion curves are determined from the tomographic maps and eleven main regions, each one characterized by one kind of dispersion curves, are identified. The average dispersion curves obtained for each region are extended to 150 s by adding data from the tomographic study of and inverted using a non-linear procedure. As a result of the inversion process, a set of models of the S-wave velocity vs. depth in the crust and upper mantle are found. In six regions, we identify a typically oceanic crust and upper mantle structure, while in the other two the models are consistent with the presence of a continental structure. Two regions, located over the major geological zones of the accretionary crust of the Caribbean region, are characterized by a peculiar crust and upper mantle structure, indicating the presence of lithospheric roots reaching, at least, about 200 km of depth. (author)

  2. Preserving Geological Samples and Metadata from Polar Regions

    Science.gov (United States)

    Grunow, A.; Sjunneskog, C. M.

    2011-12-01

    The Office of Polar Programs at the National Science Foundation (NSF-OPP) has long recognized the value of preserving earth science collections due to the inherent logistical challenges and financial costs of collecting geological samples from Polar Regions. NSF-OPP established two national facilities to make Antarctic geological samples and drill cores openly and freely available for research. The Antarctic Marine Geology Research Facility (AMGRF) at Florida State University was established in 1963 and archives Antarctic marine sediment cores, dredge samples and smear slides along with ship logs. The United States Polar Rock Repository (USPRR) at Ohio State University was established in 2003 and archives polar rock samples, marine dredges, unconsolidated materials and terrestrial cores, along with associated materials such as field notes, maps, raw analytical data, paleomagnetic cores, thin sections, microfossil mounts, microslides and residues. The existence of the AMGRF and USPRR helps to minimize redundant sample collecting, lessen the environmental impact of doing polar field work, facilitates field logistics planning and complies with the data sharing requirement of the Antarctic Treaty. USPRR acquires collections through donations from institutions and scientists and then makes these samples available as no-cost loans for research, education and museum exhibits. The AMGRF acquires sediment cores from US based and international collaboration drilling projects in Antarctica. Destructive research techniques are allowed on the loaned samples and loan requests are accepted from any accredited scientific institution in the world. Currently, the USPRR has more than 22,000 cataloged rock samples available to scientists from around the world. All cataloged samples are relabeled with a USPRR number, weighed, photographed and measured for magnetic susceptibility. Many aspects of the sample metadata are included in the database, e.g. geographical location, sample

  3. Characterization of the Morphometry of Impact Craters Hosting Polar Deposits in Mercury's North Polar Region

    Science.gov (United States)

    Talpe Matthieu; Zuber, Maria T.; Yang, Di; Neumann, Gregory A.; Solomon, Sean C.; Mazarico, Erwan; Vilas, Faith

    2012-01-01

    Earth-based radar images of Mercury show radar-bright material inside impact craters near the planet s poles. A previous study indicated that the polar-deposit-hosting craters (PDCs) at Mercury s north pole are shallower than craters that lack such deposits. We use data acquired by the Mercury Laser Altimeter on the MESSENGER spacecraft during 11 months of orbital observations to revisit the depths of craters at high northern latitudes on Mercury. We measured the depth and diameter of 537 craters located poleward of 45 N, evaluated the slopes of the northern and southern walls of 30 PDCs, and assessed the floor roughness of 94 craters, including nine PDCs. We find that the PDCs appear to have a fresher crater morphology than the non-PDCs and that the radar-bright material has no detectable influence on crater depths, wall slopes, or floor roughness. The statistical similarity of crater depth-diameter relations for the PDC and non-PDC populations places an upper limit on the thickness of the radar-bright material (< 170 m for a crater 11 km in diameter) that can be refined by future detailed analysis. Results of the current study are consistent with the view that the radar-bright material constitutes a relatively thin layer emplaced preferentially in comparatively young craters.

  4. Unstable ductile fracture conditions in upper shelf region

    International Nuclear Information System (INIS)

    Nakano, Yoshifumi; Kubo, Takahiro

    1985-01-01

    The phenomenon of unstability of ductile fracture in the upper shelf region of a forged steel for nuclear reactor pressure vessels A508 Cl. 3 was studied with a large compliance apparatus, whose spring constants were 100, 170 and 230 kgf/mm, at the test temperatures of 100, 200 and 300 0 C and at the loading rates of 2, 20 and 200 mm/min in the crosshead speed. The main results obtained are as follows: (1) The fracture modes of the specimens consisted of (a) stable fracture, (b) unstable fracture which leads to a complete fracture rapidly and (c) quasiunstable fracture which does not lead to a complete fracture though a rapid extension of ductile crack takes place. (2) Side groove, high temperature or small spring constant made a ductile crack more unstable. (3) High temperature or large spring constant made the occurrence of quasiunstable fracture easier. (4) Quasiunstable ductile fracture took place before the maximum load, that is, at the J integral value of about 10 kgf/mm. The initiation of a microscopic ductile crack, therefore, seems to lead to quasiunstable fracture. (5) The concept that unstable ductile fracture takes place when Tsub(app) exceeds Tsub(mat) seems applicable only to the case in which unstable ductile fracture takes place after the maximum load has been exceeded. (author)

  5. Light in Condensed Matter in the Upper Atmosphere as the Origin of Homochirality: Circularly Polarized Light from Rydberg Matter

    Science.gov (United States)

    Holmlid, Leif

    2009-08-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  6. Light in condensed matter in the upper atmosphere as the origin of homochirality: circularly polarized light from Rydberg matter.

    Science.gov (United States)

    Holmlid, Leif

    2009-01-01

    Clouds of the condensed excited Rydberg matter (RM) exist in the atmospheres of comets and planetary bodies (most easily observed at Mercury and the Moon), where they surround the entire bodies. Vast such clouds are recently proposed to exist in the upper atmosphere of Earth (giving rise to the enormous features called noctilucent clouds, polar mesospheric clouds, and polar mesospheric summer radar echoes). It has been shown in experiments with RM that linearly polarized visible light scattered from an RM layer is transformed to circularly polarized light with a probability of approximately 50%. The circular Rydberg electrons in the magnetic field in the RM may be chiral scatterers. The magnetic and anisotropic RM medium acts as a circular polarizer probably by delaying one of the perpendicular components of the light wave. The delay process involved is called Rabi-flopping and gives delays of the order of femtoseconds. This strong effect thus gives intense circularly polarized visible and UV light within RM clouds. Amino acids and other chiral molecules will experience a strong interaction with this light field in the upper atmospheres of planets. The interaction will vary with the stereogenic conformation of the molecules and in all probability promote the survival of one enantiomer. Here, this strong effect is proposed to be the origin of homochirality. The formation of amino acids in the RM clouds is probably facilitated by the catalytic effect of RM.

  7. Cloud and surface textural features in polar regions

    Science.gov (United States)

    Welch, Ronald M.; Kuo, Kwo-Sen; Sengupta, Sailes K.

    1990-01-01

    The study examines the textural signatures of clouds, ice-covered mountains, solid and broken sea ice and floes, and open water. The textural features are computed from sum and difference histogram and gray-level difference vector statistics defined at various pixel displacement distances derived from Landsat multispectral scanner data. Polar cloudiness, snow-covered mountainous regions, solid sea ice, glaciers, and open water have distinguishable texture features. This suggests that textural measures can be successfully applied to the detection of clouds over snow-covered mountains, an ability of considerable importance for the modeling of snow-melt runoff. However, broken stratocumulus cloud decks and thin cirrus over broken sea ice remain difficult to distinguish texturally. It is concluded that even with high spatial resolution imagery, it may not be possible to distinguish broken stratocumulus and thin clouds from sea ice in the marginal ice zone using the visible channel textural features alone.

  8. Anthropogenic antibiotic resistance genes mobilization to the polar regions.

    Science.gov (United States)

    Hernández, Jorge; González-Acuña, Daniel

    2016-01-01

    Anthropogenic influences in the southern polar region have been rare, but lately microorganisms associated with humans have reached Antarctica, possibly from military bases, fishing boats, scientific expeditions, and/or ship-borne tourism. Studies of seawater in areas of human intervention and proximal to fresh penguin feces revealed the presence of Escherichia coli strains least resistant to antibiotics in penguins, whereas E. coli from seawater elsewhere showed resistance to one or more of the following antibiotics: ampicillin, tetracycline, streptomycin, and trim-sulfa. In seawater samples, bacteria were found carrying extended-spectrum β-lactamase (ESBL)-type CTX-M genes in which multilocus sequencing typing (MLST) showed different sequence types (STs), previously reported in humans. In the Arctic, on the contrary, people have been present for a long time, and the presence of antibiotic resistance genes (ARGs) appears to be much more wide-spread than was previously reported. Studies of E coli from Arctic birds (Bering Strait) revealed reduced susceptibility to antibiotics, but one globally spreading clone of E. coli genotype O25b-ST131, carrying genes of ESBL-type CTX-M, was identified. In the few years between sample collections in the same area, differences in resistance pattern were observed, with E. coli from birds showing resistance to a maximum of five different antibiotics. Presence of resistance-type ESBLs (TEM, SHV, and CTX-M) in E. coli and Klebsiella pneumoniae was also confirmed by specified PCR methods. MLST revealed that those bacteria carried STs that connect them to previously described strains in humans. In conclusion, bacteria previously related to humans could be found in relatively pristine environments, and presently human-associated, antibiotic-resistant bacteria have reached a high global level of distribution that they are now found even in the polar regions.

  9. Physics with polarized beams above GeV region

    International Nuclear Information System (INIS)

    Yokosawa, A.

    1980-01-01

    During the past several years many exciting and unexpected results have been observed in experiments with polarized beams. Those results are reviewed briefly. A new polarized beam line up to 600 GeV/c is also discussed. 4 figures

  10. Regional anesthesia procedures for shoulder and upper arm surgery upper extremity update--2005 to present.

    Science.gov (United States)

    Sripada, Ramprasad; Bowens, Clifford

    2012-01-01

    This review of the literature since 2005 assesses developments of RA techniques commonly used for shoulder surgery, and their effectiveness for postoperative analgesia. Advantages of regional techniques include site-specific anesthesia and decreased postoperative opioid use. For shoulder surgeries, the ISB provides effective analgesia with minimal complications, whereas the impacts of IA single-injections remain unclear. When combined with GA, ISB can be used in lower volumes and reducing the complications for shoulder and proximal upper extremity. USG ISB and SCB are both effective and safe for shoulder surgery with a low incidence of complications, especially PONS.53 When compared with intravenous patient-controlled opioid analgesia, a perineural LA infusion using a disposable pump with patient-controlled LA bolus function has led to better pain relief and functional recovery while decreasing the need for rescue analgesics and the number of adverse events after ambulatory orthopedic surgery. The most remarkable advance in RA in the past 5 years is the increased usage of USG. Although there are no large-scale prospective studies to show the safety, efficacy, and success and complication rates for USG blocks, USG RA theoretically could have less risk for neurologic symptoms, except for those induced by LA (less likely perineurally, much more likely intraneurally). The next "quantum leap" lies in reducing LA concentrations and augmenting anesthetic-analgesic effects with perineural additives (including clonidine, buprenorphine, and likely low-dose dexamethasone). Since 2005, perineural catheters have been an analgesic option that offers improved pain relief among other benefits, and are now being used at home. It is clear that patients benefit greatly from a single injection and continuous nerve block for postoperative pain management,but the financial and logistical aspects need to be resolved, not to mention the phrenic hemiparesis coin toss. Whether combined

  11. Tropospheric ozone variations in polar regions; Troposphaerische Ozonvariationen in Polarregionen

    Energy Technology Data Exchange (ETDEWEB)

    Wessel, S.

    1997-08-01

    An extensive analysis for the description of chemical and dynamical processes during tropospheric ozone minima in the Arctic and Antarctic was carried out in this work. One main task was the analysis of the source regions of tropospheric ozone destruction and the following transport of ozone depleted air masses to the measuring site. Furtheron the ozone destruction mechanism itself should be examined as well as the efficiency of heterogeneous reactions for the regeneration of non-reative bromine compounds, which seems to be necessary because bromine may be the key component in the destruction of tropospheric ozone in polar regions. (orig./KW) [Deutsch] In der vorliegenden Arbeit wurde eine umfangreiche Analyse zur Beschreibung der chemischen und dynamischen Prozesse waehrend troposphaerischer Ozonminima in der Arktis und Antarktis durchgefuehrt. Ziel war es, die Quellregion des Ozonabbaus sowie den ausloesenden ozonabbauenden Mechanismus zu benennen, die Effizienz heterogener Reaktionen zur Regenerierung nichtreaktiver Bromverbindungen waehrend des Ozonabbaus zu ermitteln und den Transport der ozonarmen Luftmassen zum Messort zu untersuchen. (orig./KW)

  12. Boundary layer polarization and voltage in the 14 MLT region

    Science.gov (United States)

    Lundin, R.; Yamauchi, M.; Woch, J.; Marklund, G.

    1995-05-01

    Viking midlatitude observations of ions and electrons in the postnoon auroral region show that field-aligned acceleration of electrons and ions with energies up to a few kiloelectron volts takes place. The characteristics of the upgoing ion beams and the local transverse electric field observed by Viking indicate that parallel ion acceleration is primarily due to a quasi-electrostatic field-aligned acceleration process below Viking altitudes, i.e., below 10,000-13,500 km. A good correlation is found between the maximum upgoing ion beam energy and the depth of the local potential well determined by the Viking electric field experiment within dayside 'ion inverted Vs.' The total transverse potential throughout the entire region near the ion inverted Vs. is generally much higher than the field-aligned potential and may reach well above 10 kV. However, the detailed mapping of the transverse potential out to the boundary layer, a fundamental issue which remains controversial, was not attempted here. An important finding in this study is the strong correlation between the maximum up going ion beam energy of dayside ion inverted Vs and the solar wind velocity. This suggests a direct coupling of the solar wind plasma dynamo/voltage generator to the region of field-aligned particle acceleration. The fact that the center of dayside ion inverted Vs coincide with convection reversals/flow stagnation and upward Birkeland currents on what appears to be closed field lines (Woch et al., 1993), suggests that field-aligned potential structures connect to the inner part of an MHD dyanmo in the low-latitude boundary layer. Thus the Viking observations substantiate the idea of a solar wind induced boundary layer polarization where negatively charged perturbations in the postnoon sector persistently develops along the magnetic field lines, establishing accelerating potential drops along the geomagnetic field lines in the 0.5-10 kV range.

  13. SYMPOSIUM ON REMOTE SENSING IN THE POLAR REGIONS

    Science.gov (United States)

    The Arctic Institute of North America long has been interested in encouraging full and specific attention to applications of remote sensing to polar...research problems. The major purpose of the symposium was to acquaint scientists and technicians concerned with remote sensing with some of the...special problems of the polar areas and, in turn, to acquaint polar scientists with the potential of the use of remote sensing . The Symposium therefore was

  14. The effect of nodalization and temperature of reactor upper region: Sensitivity analysis for APR-1400 LBLOCA

    International Nuclear Information System (INIS)

    Kang, Dong Gu

    2017-01-01

    Highlights: • The nodalization of APR-1400 was modified to reflect the characteristic of upper region temperature. • The effect of nodalization and temperature of reactor upper region on LBLOCA consequence was evaluated. • The modification of nodalization is an essential prerequisite in APR-1400 LBLOCA analysis. - Abstract: In best estimate (BE) calculation, the definition of system nodalization is important step influencing the prediction accuracy for specific thermal-hydraulic phenomena. The upper region of reactor is defined as the region of the upper guide structure (UGS) and upper dome. It has been assumed that the temperature of upper region is close to average temperature in most large break loss of coolant accident (LBLOCA) analysis cases. However, it was recently found that the temperature of upper region of APR-1400 reactor might be little lower than or similar to hot leg temperature through the review of detailed design data. In this study, the nodalization of APR-1400 was modified to reflect the characteristic of upper region temperature, and the effect of nodalization and temperature of reactor upper region on LBLOCA consequence was evaluated by sensitivity analysis including best estimate plus uncertainty (BEPU) calculation. In basecase calculation, in case of modified version, the peak cladding temperature (PCT) in blowdown phase became higher and the blowdown quenching (or cooling) was significantly deteriorated as compared to original case, and as a result, the cladding temperature in reflood phase became higher and the final quenching was also delayed. In addition, thermal-hydraulic parameters were compared and analyzed to investigate the effect of change of upper region on cladding temperature. In BEPU analysis, the 95 percentile PCT used in current regulatory practice was increased due to the modification of upper region nodalization, and it occurred in the reflood phase unlike original case.

  15. Polarization of photoneutrons from the threshold region of 208Pb

    International Nuclear Information System (INIS)

    Holt, R.J.; Jackson, H.E.

    1975-01-01

    In order to determine the parities of several resonances in 208 Pb, the polarization of photoneutrons from the 208 Pb(γ,n(pol)) 207 Pb reaction was measured. This represents the first measurement of the polarization of photoneutrons from resonances near threshold. The observations are tabulated. (SDF)

  16. Saturnian north polar region: a triangle inside the hexagon?

    Science.gov (United States)

    Kochemasov, Gennady G.

    2010-05-01

    The famous and "mysterious" stable hexagon structure around the North Pole of Saturn was earlier interpreted as projections of faces of a structural tetrahedron [1]. This "hidden" simplest Plato's polyhedron is a result of an interference of four fundamental (wave 1) warping waves having in any rotating celestial body four directions: orthogonal and diagonal. Origin of the warping waves in any celestial body is due to their movements in elliptical keplerian orbits with periodically changing accelerations. The structural tetrahedron is an intrinsic geometric feature marking the celestial bodies ubiquitous tectonic dichotomy as in a tetrahedron always there is an opposition of a face (expansion) and a vertex (contraction). In the saturnian case the tetrahedron shows a face at the north and a vertex at the south. Morphologically this is manifested by the hexagon and opposing it in the south a vertex. Blue and pink hues of the northern and southern hemispheres also underline the tectonic dichotomy. These geometric expressions are enforced by a subtle dark equilateral triangle appearing in the image PIA11682 also around the north pole and inside the hexagon (the triangle side is about 15000 km long). One angle of the triangle is clearly visible, another one just shows itself and the third one is barely distinguished. The sides of the triangle are not strait lines but slightly broken amidst lines what makes the triangle appear a bit hexagonal (spherical) and the angle is a bit bigger than 60 degrees of a classical equilateral triangle (~70 degrees). The central part of the triangle is not imaged (a black hole in the PIA11682). This image also confirms that the wide northern polar region is also densely "peppered" with bright cloudy more or less isometric spots on average 400 to 800 km across as in other latitudinal belts of Saturn [2, 3, 4]. Earlier they were observed in IR wavelengths, now they show themselves in visible wavelengths. Their origin and size were

  17. Some like it cold: microbial transformations of mercury in polar regions

    DEFF Research Database (Denmark)

    Barkay, Tamar; Kroer, Niels A.; Poulain, Alexandre J.

    2011-01-01

    The contamination of polar regions with mercury that is transported from lower latitudes as inorganic mercury has resulted in the accumulation of methylmercury (MeHg) in food chains, risking the health of humans and wildlife. While production of MeHg has been documented in polar marine and terres......The contamination of polar regions with mercury that is transported from lower latitudes as inorganic mercury has resulted in the accumulation of methylmercury (MeHg) in food chains, risking the health of humans and wildlife. While production of MeHg has been documented in polar marine...

  18. Protecting polar wilderness : Just a western philosophical idea or a useful concept for regulating human activities in the polar regions?

    NARCIS (Netherlands)

    Bastmeijer, Kees; Leary, D.; Koivurova, T.; Alfredsson, G.

    2009-01-01

    Governments involved in Arctic and Antarctic governance have been well aware of the increasing human pressure on the Polar Regions and particularly the last two decades many initiatives have been taken to protect the Arctic and Antarctic environment. But what values are to be protected? This paper

  19. Specialty Crop Profile: Blueberries for the Upper Piedmont and Mountain Regions

    OpenAIRE

    Bratsch, Tony

    2009-01-01

    Discusses blueberries as a small fruit crop for the upper Piedmont and mountain regions of Virginia. Provides information about best ways to plant the blueberries, mulching, irrigation, fertilization, pruning, harvesting and handling, marketing and more.

  20. New Data on Conodonts of the Upper Devonian of the Polar Urals (Ostantsovy Section, Malaya Usa River

    Directory of Open Access Journals (Sweden)

    M.A. Soboleva

    2016-09-01

    Full Text Available The main features of the Upper Devonian sediments on the right side of the Ostantsovy Creek (the left tributary of the Malaya Usa River in the eastern part of the Bielsko-Eletskaya structural formational belt on the western slope of the Polar Urals have been considered. The late Frasnian age of these sediments has been determined on the basis of conodonts (the linguiformis zone of the standard conodont scale. The transition from clastic and organic limestones with massive stromatoporoid forms to limestones with fused (reservoir stromatoporoid forms and Palmatolepis biofacies is indicative of the transgressive shift of the linguiformis phase. This transgressive level is an indirect expression of the Upper Kellwasser global event.

  1. Power spectra of mesospheric velocities in polar regions

    Science.gov (United States)

    Czechowsky, P.; Ruster, R.

    1985-01-01

    The mobile SOUSY radar was operated on Andoya in Northern Norway during the MAP/WINE campaign from November 1983 to February 1984 and for about two weeks in June 1984 to study the seasonal dependence of mesospheric structures and dynamics at polar latitudes. During the winter period, measurements were carried out on 57 days, primarily in coordination with the schedule of the rocket experiments. Echoes were detected in the troposphere and stratosphere up to 30 km and at mesospheric heights from about 50 to 90 km with a distinct maximum around noon. In summer, the radar system was operated continuously from 19th to the 28th of June 1984. Echoes occurred almost for 24 hours in the height range from 70 to 95 km showing no recognizable diurnal variation. Similar observations in polar latitudes were carried out for several years with the Poker Flat Radar in Alaska.

  2. Dayside and nightside contributions to the cross polar cap potential: placing an upper limit on a viscous-like interaction

    Directory of Open Access Journals (Sweden)

    S. E. Milan

    2004-11-01

    Full Text Available Observations of changes in size of the ionospheric polar cap allow the dayside and nightside reconnection rates to be quantified. From these it is straightforward to estimate the rate of antisunward transport of magnetic flux across the polar regions, quantified by the cross polar cap potential ΦPC. When correlated with upstream measurements of the north-south component of the IMF, ΦPC is found to increase for more negative Bz, as expected. However, we also find that ΦPC does not, on average, decrease to zero, even for strongly northward IMF. In the past this has been interpreted as evidence for a viscous interaction between the magnetosheath flow and the outer boundaries of the magnetosphere. In contrast, we show that this is the consequence of flows excited by tail reconnection, which is inherently uncorrelated with IMF Bz.

  3. Polarization Signatures of Kink Instabilities in the Blazar Emission Region from Relativistic Magnetohydrodynamic Simulations

    International Nuclear Information System (INIS)

    Zhang, Haocheng; Taylor, Greg; Li, Hui; Guo, Fan

    2017-01-01

    Kink instabilities are likely to occur in the current-carrying magnetized plasma jets. Recent observations of the blazar radiation and polarization signatures suggest that the blazar emission region may be considerably magnetized. While the kink instability has been studied with first-principle magnetohydrodynamic (MHD) simulations, the corresponding time-dependent radiation and polarization signatures have not been investigated. In this paper, we perform comprehensive polarization-dependent radiation modeling of the kink instability in the blazar emission region based on relativistic MHD (RMHD) simulations. We find that the kink instability may give rise to strong flares with polarization angle (PA) swings or weak flares with polarization fluctuations, depending on the initial magnetic topology and magnetization. These findings are consistent with observations. Compared with the shock model, the kink model generates polarization signatures that are in better agreement with the general polarization observations. Therefore, we suggest that kink instabilities may widely exist in the jet environment and provide an efficient way to convert the magnetic energy and produce multiwavelength flares and polarization variations.

  4. Polarization Signatures of Kink Instabilities in the Blazar Emission Region from Relativistic Magnetohydrodynamic Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Haocheng; Taylor, Greg [Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131 (United States); Li, Hui; Guo, Fan [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2017-02-01

    Kink instabilities are likely to occur in the current-carrying magnetized plasma jets. Recent observations of the blazar radiation and polarization signatures suggest that the blazar emission region may be considerably magnetized. While the kink instability has been studied with first-principle magnetohydrodynamic (MHD) simulations, the corresponding time-dependent radiation and polarization signatures have not been investigated. In this paper, we perform comprehensive polarization-dependent radiation modeling of the kink instability in the blazar emission region based on relativistic MHD (RMHD) simulations. We find that the kink instability may give rise to strong flares with polarization angle (PA) swings or weak flares with polarization fluctuations, depending on the initial magnetic topology and magnetization. These findings are consistent with observations. Compared with the shock model, the kink model generates polarization signatures that are in better agreement with the general polarization observations. Therefore, we suggest that kink instabilities may widely exist in the jet environment and provide an efficient way to convert the magnetic energy and produce multiwavelength flares and polarization variations.

  5. Adaptive polarization image fusion based on regional energy dynamic weighted average

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong-qiang; PAN Quan; ZHANG Hong-cai

    2005-01-01

    According to the principle of polarization imaging and the relation between Stokes parameters and the degree of linear polarization, there are much redundant and complementary information in polarized images. Since man-made objects and natural objects can be easily distinguished in images of degree of linear polarization and images of Stokes parameters contain rich detailed information of the scene, the clutters in the images can be removed efficiently while the detailed information can be maintained by combining these images. An algorithm of adaptive polarization image fusion based on regional energy dynamic weighted average is proposed in this paper to combine these images. Through an experiment and simulations,most clutters are removed by this algorithm. The fusion method is used for different light conditions in simulation, and the influence of lighting conditions on the fusion results is analyzed.

  6. Protists in the polar regions: comparing occurrence in the Arctic and Southern oceans using pyrosequencing

    Directory of Open Access Journals (Sweden)

    Christian Wolf

    2015-05-01

    Full Text Available In the ongoing discussion of the distribution of protists, whether they are globally distributed or endemic to one or both of the polar regions is the subject of heated debate. In this study, we compared next-generation sequencing data from the Arctic and the Southern oceans to reveal the extent of similarities and dissimilarities between the protist communities in the polar regions. We found a total overlap of operational taxonomic units (OTUs between the two regions of 11.2%. On closer inspection of different taxonomic groups, the overlap ranged between 5.5% (haptophytes and 14.5% (alveolates. Within the different groups, the proportion of OTUs occurring in both regions greatly differed between the polar regions. On the one hand, the overlap between these two regions is remarkable, given the geographical distance between them. On the other hand, one could expect a greater overlap of OTUs between these regions on account of the similar environmental conditions. The overlap suggests a connection between the polar regions for at least certain species or that the evolutionary divergence has been slow, relative to the timescales of isolation. The different proportions of common OTUs among the groups or regions may be a result of different life cycle strategies or environmental adaptations.

  7. Active Upper-atmosphere Chemistry and Dynamics from Polar Circulation Reversal on Titan

    Science.gov (United States)

    Teanby, Nicholas A.; Irwin, Patrick Gerard Joseph; Nixon, Conor A.; DeKok, Remco; Vinatier, Sandrine; Coustenis, Athena; Sefton-Nash, Elliot; Calcutt, Simon B.; Flasar, Michael F.

    2012-01-01

    Saturn's moon Titan has a nitrogen atmosphere comparable to Earth's, with a surface pressure of 1.4 bar. Numerical models reproduce the tropospheric conditions very well but have trouble explaining the observed middle-atmosphere temperatures, composition and winds. The top of the middle-atmosphere circulation has been thought to lie at an altitude of 450 to 500 kilometres, where there is a layer of haze that appears to be separated from the main haze deck. This 'detached' haze was previously explained as being due to the colocation of peak haze production and the limit of dynamical transport by the circulation's upper branch. Herewe report a build-up of trace gases over the south pole approximately two years after observing the 2009 post-equinox circulation reversal, from which we conclude that middle-atmosphere circulation must extend to an altitude of at least 600 kilometres. The primary drivers of this circulation are summer-hemisphere heating of haze by absorption of solar radiation and winter-hemisphere cooling due to infrared emission by haze and trace gases; our results therefore imply that these effects are important well into the thermosphere (altitudes higher than 500 kilometres). This requires both active upper-atmosphere chemistry, consistent with the detection of high-complexity molecules and ions at altitudes greater than 950 kilometres, and an alternative explanation for the detached haze, such as a transition in haze particle growth from monomers to fractal structures.

  8. NEAR-INFRARED POLARIZATION SOURCE CATALOG OF THE NORTHEASTERN REGIONS OF THE LARGE MAGELLANIC CLOUD

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jaeyeong; Pak, Soojong [School of Space Research, Kyung Hee University, 1 Seocheon-dong, Giheung-gu, Yongin, Gyeonggi-do 446-701 (Korea, Republic of); Jeong, Woong-Seob; Park, Won-Kee [Korea Astronomy and Space Science Institute, 776 Daedeok-daero, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); Tamura, Motohide, E-mail: jaeyeong@khu.ac.kr, E-mail: jeongws@kasi.re.kr [The University of Tokyo/National Astronomical Observatory of Japan/Astrobiology Center, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2016-01-15

    We present a near-infrared band-merged photometric and polarimetric catalog for the 39′ × 69′ fields in the northeastern part of the Large Magellanic Cloud (LMC), which were observed using SIRPOL, an imaging polarimeter of the InfraRed Survey Facility. This catalog lists 1858 sources brighter than 14 mag in the H band with a polarization signal-to-noise ratio greater than three in the J, H, or K{sub s} bands. Based on the relationship between the extinction and the polarization degree, we argue that the polarization mostly arises from dichroic extinctions caused by local interstellar dust in the LMC. This catalog allows us to map polarization structures to examine the global geometry of the local magnetic field, and to show a statistical analysis of the polarization of each field to understand its polarization properties. In the selected fields with coherent polarization position angles, we estimate magnetic field strengths in the range of 3−25 μG using the Chandrasekhar–Fermi method. This implies the presence of large-scale magnetic fields on a scale of around 100 parsecs. When comparing mid- and far-infrared dust emission maps, we confirmed that the polarization patterns are well aligned with molecular clouds around the star-forming regions.

  9. Analysis of aerosol optical depth evaluation in polar regions and associated uncertainties

    Directory of Open Access Journals (Sweden)

    P. Ortiz de Galisteo

    2008-04-01

    Full Text Available Some available processing algorithms used to calculate the aerosol optical depth from radiometric measurements were tested. The aim was to evaluate the associated uncertainties in polar regions due to the data processing, in order to adjust the methodology of the calculation and illustrate the importance of these error sources. The measurements were obtained during a sun photometer campaign in Ny-Ålesund within the framework of the POLAR-AOD project.

  10. Distribution of irregularities in the northern polar region determined from Hilat observations

    International Nuclear Information System (INIS)

    Macdougall, J.W.

    1990-01-01

    Three years' observations of the Hilat satellite from stations Sondre, Churchill, and Tromso have been used to study the distributions of scintillations over the northern polar region. Two regions showed enhancement. Region (1) was an enhancement of phase scintillations when the line of sight to the satellite lay along an L shell and the observing station was under the auroral oval. Region (2) is revealed most clearly by amplitude scintillations and maximizes in an annular region several degrees poleward of the auroral oval. Region (1) is most likely associated with large-scale 'blobs' of ionization in the auroral zone; region (2) appears to be due to km-scale irregularities generated in the polar cap. 17 refs

  11. Electric Mars: The first direct measurement of an upper limit for the Martian "polar wind" electric potential

    Science.gov (United States)

    Collinson, Glyn; Mitchell, David; Glocer, Alex; Grebowsky, Joseph; Peterson, W. K.; Connerney, Jack; Andersson, Laila; Espley, Jared; Mazelle, Christian; Sauvaud, Jean-André; Fedorov, Andrei; Ma, Yingjuan; Bougher, Steven; Lillis, Robert; Ergun, Robert; Jakosky, Bruce

    2015-11-01

    An important mechanism in the generation of polar wind outflow is the ambipolar electric potential which assists ions in overcoming gravity and is a key mechanism for Terrestrial ionospheric escape. At Mars, open field lines are not confined to the poles, and outflow of ionospheric electrons is observed far into the tail. It has thus been hypothesized that a similar electric potential may be present at Mars, contributing to global ionospheric loss. However, no direct measurements of this potential have been made. In this pilot study, we examine photoelectron spectra measured by the Solar Wind Electron Analyzer instrument on the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) Mars Scout to put an initial upper bound on the total potential drop in the ionosphere of Mars of Φ♂ ≾⊥ 2V , with the possibility of a further ≾4.5 V potential drop above this in the magnetotail. If the total potential drop was close to the upper limit, then strong outflows of major ionospheric species (H+, O+, and O2+) would be expected. However, if most of the potential drop is confined below the spacecraft, as expected by current theory, then such a potential would not be sufficient on its own to accelerate O2+ to escape velocities, but would be sufficient for lighter ions. However, any potential would contribute to atmospheric loss through the enhancement of Jeans escape.

  12. Polarization and infrared imaging of regions of star formation

    International Nuclear Information System (INIS)

    Moneti, A.

    1985-01-01

    Observational studies of two regions of star formation, the Taurus cloud and the BN-KL region of Orion, are presented. The magnetic field structure in the Taurus cloud was studied in order to investigate its possible role in the evolution of the cloud. It was found that the magnetic field is generally perpendicular to the elongated structures that make up the cloud, and it is deduced that the observed structure could be due to the effects of the magnetic field during the early stages of collapse. In addition, it was found that the magnetic field may have prevented the formation of massive stars by inhibiting the collapse of large cores, while not affecting the collapse of the small ones. Using a new near-infrared array camera, high resolution (1'') images of several young stars embedded in the cloud were obtained. Most of these sources have extended, spatially resolved circumstellar shells. High resolution images of the BN-KL region of Orion at four wavelengths between 1.65 and 4.7 μm were also obtained. At 1.65 μm a large trough is seen in the overall nebulosity; it is suggested that the observed trough is due to the doughnut of material around IRc2 as it obscures the background nebulosity

  13. O+ trough zones in the polar cap ionosphere-magnetosphere coupling region

    Science.gov (United States)

    Horwitz, James; Zeng, Wen; Jaafari, Fajer

    Regions of low-density troughs in O+ have been observed at 1 RE altitude in the polar cap ionosphere-magnetosphere region by the Thermal Ion Dynamics Experiment(TIDE) on the POLAR spacecraft. In this presentation, the UT Arlington Dynamic Fluid-Kinetic (DyFK) code is employed to investigate the formation of such O+ density troughs. We utilize convection paths of flux tubes in the high-latitude region as prescribed by an empirical convection model with solar wind inputs to track the evolution of ionospheric plasma transport and in particular O+ densities along these tubes with time/space. The flux tubes are subjected to auroral processes of precipitation and wave-driven ion heating when they pass through the auroral oval, which tends to elevate the plasma densities in these tubes. When the F-regions of such tubes traverse locations where the F-region is in darkness, recombination there causes the higher-altitude regions to drain and the densities to decline throughout. Owing to the varying effects of these processes, significant and low trough-like densities at higher altitudes developed along these flux tubes. The modeled densities near 6000 km altitudes will be compared with multiple POLAR passes featuring POLAR/TIDE-measured O+ densities for inside and outside of such trough regions.

  14. Papposphaera obpyramidalis (Haptophyta, Papposphaeraceae): New findings from both Polar Regions

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Egge, Jorun Karin; Heldal, Mikal

    2016-01-01

    Papposphaera obpyramidalis is reinvestigated based on additional high latitude sampling from the southern hemisphere. The material used here comprises better preserved transmission electron microscope (TEM) material including several cells with complete flagellation, as well as light microscopy (....... However, here we present also findings of the species from Arctic realms based on recent SEM surveys from the Svalbard region, indicating a bipolar distribution.......) of living material. The re-examination basically confirms the findings that were part of the species description but also adds details on, for example, nutritional mode and the presence of an underlayer of unmineralized scales. P. obpyramidalis has hitherto been considered confined to Antarctic waters...

  15. International conference on the role of the polar regions in global change: Proceedings. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.; Wilson, C.L.; Severin, B.A.B. [eds.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with the polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; and (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks, (6) paleoenvironmental studies; and, (7) aerosol and trace gases.

  16. International conference on the role of the polar regions in global change: Proceedings. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.; Wilson, C.L.; Severin, B.A.B. [eds.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks; (6) paleoenvironmental studies; and, (7) aerosols and trace gases.

  17. Regional effects of agricultural conservation practices on nutrient transport in the Upper Mississippi River Basin

    Science.gov (United States)

    Garcia, Ana Maria.; Alexander, Richard B.; Arnold, Jeffrey G.; Norfleet, Lee; White, Michael J.; Robertson, Dale M.; Schwarz, Gregory E.

    2016-01-01

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  18. Regional Effects of Agricultural Conservation Practices on Nutrient Transport in the Upper Mississippi River Basin.

    Science.gov (United States)

    García, Ana María; Alexander, Richard B; Arnold, Jeffrey G; Norfleet, Lee; White, Michael J; Robertson, Dale M; Schwarz, Gregory

    2016-07-05

    Despite progress in the implementation of conservation practices, related improvements in water quality have been challenging to measure in larger river systems. In this paper we quantify these downstream effects by applying the empirical U.S. Geological Survey water-quality model SPARROW to investigate whether spatial differences in conservation intensity were statistically correlated with variations in nutrient loads. In contrast to other forms of water quality data analysis, the application of SPARROW controls for confounding factors such as hydrologic variability, multiple sources and environmental processes. A measure of conservation intensity was derived from the USDA-CEAP regional assessment of the Upper Mississippi River and used as an explanatory variable in a model of the Upper Midwest. The spatial pattern of conservation intensity was negatively correlated (p = 0.003) with the total nitrogen loads in streams in the basin. Total phosphorus loads were weakly negatively correlated with conservation (p = 0.25). Regional nitrogen reductions were estimated to range from 5 to 34% and phosphorus reductions from 1 to 10% in major river basins of the Upper Mississippi region. The statistical associations between conservation and nutrient loads are consistent with hydrological and biogeochemical processes such as denitrification. The results provide empirical evidence at the regional scale that conservation practices have had a larger statistically detectable effect on nitrogen than on phosphorus loadings in streams and rivers of the Upper Mississippi Basin.

  19. Modeling polar cap F-region patches using time varying convection

    International Nuclear Information System (INIS)

    Sojka, J.J.; Bowline, M.D.; Schunk, R.W.; Decker, D.T.; Valladares, C.E.; Sheehan, R.; Anderson, D.N.; Heelis, R.A.

    1993-01-01

    Here the authors present the results of computerized simulations of the polar cap regions which were able to model the formation of polar cap patches. They used the Utah State University Time-Dependent Ionospheric Model (TDIM) and the Phillips Laboratory (PL) F-region models in this work. By allowing a time varying magnetospheric electric field in the models, they were able to generate the patches. This time varying field generates a convection in the ionosphere. This convection is similar to convective changes observed in the ionosphere at times of southward pointing interplanetary magnetic field, due to changes in the B y component of the IMF

  20. Studies of the polar MLT region using SATI airglow measurements

    Science.gov (United States)

    Cho, Youngmin

    To investigate atmospheric dynamics of the MLT (Mesosphere and Lower Thermosphere) region, a ground-based instrument called SATI (Spectral Airglow Temperature Imager) was developed at York University. The rotational temperatures and emission rates of the OH (6-2) Meinel band and the O2 (0-1) Atmospheric band have been measured in the MLT region by the SATI instrument at Resolute Bay (74.68°N, 94.90°W) since November, 2001, and at the King Sejong station (62.22°S, 58.75°W) since February, 2002. The MLT measurements are examined for periodic oscillations in the ambient temperature and airglow emission rate. A dominant and coherent 4-hr oscillation is seen in both the OH and O2 temperature and emission rate at Resolute Bay in November, 2001. Tidal variation with a 12 hour period is shown in hourly averaged temperatures of the season 2001--2002 and the season 2003--2004. In addition, planetary waves with periods of 3 and 4.5 days are also seen in a longer interval. The observations at high latitudes have revealed that temperatures and emission rates are higher around the winter solstice. MLT cooling events were found at Resolute Bay in December, 2001 and February, 2002. They are compared with the UKMO (UK Meteorological Office) stratospheric assimilated data, and the MLT coolings coincide in time with the stratospheric warmings. A consistent inverse relationship of the OH temperatures and temperatures at 0.316 hPa is presented in the comparison. In previous studies of wave perturbations, the background (mean) values were normally subtracted from the instantaneous signal, but in the present investigation this was not done, allowing the long-term relationship to be examined. A positive relationship of the temperature and emission rate is seen from the SATI measurements for both short and long-term variations, suggesting that similar dynamical processes are responsible for both. This relationship is supported by satellite data from the SABER (Sounding of the

  1. Initial Alignment for SINS Based on Pseudo-Earth Frame in Polar Regions.

    Science.gov (United States)

    Gao, Yanbin; Liu, Meng; Li, Guangchun; Guang, Xingxing

    2017-06-16

    An accurate initial alignment must be required for inertial navigation system (INS). The performance of initial alignment directly affects the following navigation accuracy. However, the rapid convergence of meridians and the small horizontalcomponent of rotation of Earth make the traditional alignment methods ineffective in polar regions. In this paper, from the perspective of global inertial navigation, a novel alignment algorithm based on pseudo-Earth frame and backward process is proposed to implement the initial alignment in polar regions. Considering that an accurate coarse alignment of azimuth is difficult to obtain in polar regions, the dynamic error modeling with large azimuth misalignment angle is designed. At the end of alignment phase, the strapdown attitude matrix relative to local geographic frame is obtained without influence of position errors and cumbersome computation. As a result, it would be more convenient to access the following polar navigation system. Then, it is also expected to unify the polar alignment algorithm as much as possible, thereby further unifying the form of external reference information. Finally, semi-physical static simulation and in-motion tests with large azimuth misalignment angle assisted by unscented Kalman filter (UKF) validate the effectiveness of the proposed method.

  2. Phytoremediation of disturbed lands in Polar Regions of Russia

    Science.gov (United States)

    Shamsutdinova, Evgeniya

    2017-04-01

    In the Northern regions the problem of restoration of disturbed lands as a result of anthropogenic activities is particularly acut. A large role for the success of native plants to take hold and re-establish themselves is to allow the natural process to work without human intervention. However observation shows that low reserves of available moisture, poor soil nutrients, exposure to wind and water erosion make impossible of a complete restoration of lands due to natural revegetation. One of the methods used to minimize the effect of these factors is the phytoremediation. Research on the Pelyatinskom gas condensate field in the Taimyr Dolgano-Nenets municipal district revealed the efficacy of biological remediation of awnless brome, wildrye siberian, red fescue and kentucky bluegrass. Geobotanical studies of the tailings fields in Yakutia showed that for the phytoremediation of tailings of alluvial deposits of diamonds slough grass can be successfully used, and on the dumps of coal deposits with a high degree of survival of the willow, poplar, larch, alder stand and pine. Development of technology for remediation of placer gold deposits of the Komsomol mine and Bilibino in Chukotka has shown the effectiveness of sowing common oat, wildrye and larch. The study of the experience of recultivation on objects of the "Transneft-Baltic" in the North-Western Federal district allowed us to select as the recommended mixtures of species: meadow fescue, cocksfoot, timothy grass, white and alsike clover and alfalfa. The multicomponent mixture of red fescue, awnless brome, meadow fescue, timothy grass, couch grass, kentucky bluegrass, beckman's grass were successfully used at the mine of the Bovanenkovo oil and gas condensate field. On the technological grounds of the complex pumping station in the Yamalo-Nenets Autonomous area willows were planted. Pine and willow trees were planted on quarry workings in the Northern taiga of Western Siberia land .Planting of pines has shown

  3. Application of NASA's Advanced Life Support Technologies in Polar Regions

    Science.gov (United States)

    Bubenheim, David L.

    1997-01-01

    The problems of obtaining adequate pure drinking water and disposing of liquid and solid waste in the U.S Arctic, a region where virtually all water is frozen solid for much of the year, has led to unsanitary solutions. Sanitation and a safe water supply are particularly problems in rural villages. These villages are without running water and use plastic buckets for toilets. The outbreak of diseases is believed to be partially attributable to exposure to human waste and lack of sanitation. Villages with the most frequent outbreaks of disease are those in which running water is difficult to obtain. Waste is emptied into open lagoons, rivers, or onto the sea coast. It does not degrade rapidly and in addition to affecting human health, can be harmful to the fragile ecology of the Arctic and the indigenous wildlife and fish populations. Current practices for waste management and sanitation pose serious human hazards as well as threaten the environment. NASA's unique knowledge of water/wastewater treatment systems for extreme environments, identified in the Congressional Office of Technology Assessment report entitled An Alaskan Challenge: Native Villagt Sanitation, may offer practical solutions addressing the issues of safe drinking water and effective sanitation practices in rural villages. NASA's advanced life support technologies are being combined with Arctic science and engineering knowledge to address the unique needs of the remote communities of Alaska through the Advanced Life Systems for Extreme Environments (ALSEE) project. ALSEE is a collaborative effort involving the NASA, the State of Alaska, the University of Alaska, the North Slope Borough of Alaska, Ilisagvik College in Barrow and the National Science Foundation (NSF). The focus is a major issue in the State of Alaska and other areas of the Circumpolar North; the health and welfare of its people, their lives and the subsistence lifestyle in remote communities, economic opportunity, and care for the

  4. Investigation of the dispersion of airborne pollutants in the Upper Rhine and Lake Constance region

    International Nuclear Information System (INIS)

    Fiedler, F.; Adrian, G.; Kohler, M.

    1991-01-01

    The aim of the project is to calculate the regional flow and propagation conditions using the expensive three-dimensional meteorological model, the ''Karlsruher Atmosphaerisches Mesoskaliges Modell'' (KAMM) in order to derive the immission and the deposition of the conducting substance of pollutant matter, i.e., sulphur dioxide. In this report, calculations of the flowing field are described for the region Upper Rhine - Lake of Constance''. In the last part, the concentration fields for SO 2 are calculated for the region for typical large-area atmospheric conditions with disclosure of sources. An appraising discussion of the results concludes this work. (orig.) [de

  5. 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.

  6. Tourniquet Deflation Prior to 20 Minutes in Upper Extremity Intravenous Regional Anesthesia.

    Science.gov (United States)

    Gurich, Richard W; Langan, Justin W; Teasdall, Robert J; Tanner, Stephanie L; Sanders, John L

    2018-03-01

    Bier blocks, or intravenous regional anesthesia (IVRA), are a method of anesthesia for upper extremity surgeries. This study reports our experience with tourniquet deflation prior to 20 minutes with upper extremity IVRA. This study was designed as a retrospective cohort analysis. Records, including intraoperative and immediate postoperative anesthesia notes, of 430 patients who underwent IVRA with an upper extremity Bier block and a corresponding tourniquet time of less than 20 minutes were reviewed. Patient demographics, procedure(s) performed, American Society of Anesthesiologists scores, volume of lidocaine used in Bier block, tourniquet time, and any complications were recorded. This cohort consisted of 127 males and 303 females. The 3 most common procedures performed were carpal tunnel release (315), trigger finger release (47), and excision of masses (34). The average tourniquet time for this cohort was 16 minutes (range, 9-19 minutes), and the average volume of lidocaine (0.5% plain) injected was 44 mL (range, 30-70 mL). A tourniquet time of 17 minutes or less was observed in 339 patients, and 170 patients had tourniquet times of 15 minutes or less. Five complications were recorded: intraoperative vomiting, mild postoperative nausea/vomiting, severe postoperative nausea and vomiting, and transient postoperative hypotension that responded to a fluid bolus. No major complications were observed in our cohort of upper extremity IVRA and tourniquet times of less than 20 minutes. Several variables play a role in the safety of upper extremity IVRA.

  7. Diversity and dispersal capacities of a terrestrial algal genus Klebsormidium (Streptophyta) in polar regions

    Czech Academy of Sciences Publication Activity Database

    Ryšánek, D.; Elster, Josef; Kováčik, L.; Škaloud, P.

    2016-01-01

    Roč. 92, č. 4 (2016), s. 1-9, č. článku fiw039. ISSN 0168-6496 Institutional support: RVO:67985939 Keywords : genetic diversity * Klebsormidium * phylogeography * polar regions Subject RIV: EH - Ecology , Behaviour Impact factor: 3.720, year: 2016

  8. Malaysia's EOC Strategy in Strengthening the Science Knowledge, Awareness and National Interest towards the Polar Regions

    Science.gov (United States)

    Shabudin, Ahmad Firdaus Ahmad; Said, Noor Azzah; Rahim, Rashidah Abdul; Ng, Theam Foo

    2016-01-01

    This study aims to examine Malaysia's involvement in the Polar Regions, in the context of education, outreach, and communication (EOC), and consequently, to determine the effectiveness of these initiatives. Using qualitative and quantitative research analyses, this study found that Malaysia's experiences in EOC can be used to increase public…

  9. Insights into bird wing evolution and digit specification from polarizing region fate maps.

    Science.gov (United States)

    Towers, Matthew; Signolet, Jason; Sherman, Adrian; Sang, Helen; Tickle, Cheryll

    2011-08-09

    The proposal that birds descended from theropod dinosaurs with digits 2, 3 and 4 was recently given support by short-term fate maps, suggesting that the chick wing polarizing region-a group that Sonic hedgehog-expressing cells-gives rise to digit 4. Here we show using long-term fate maps that Green fluorescent protein-expressing chick wing polarizing region grafts contribute only to soft tissues along the posterior margin of digit 4, supporting fossil data that birds descended from theropods that had digits 1, 2 and 3. In contrast, digit IV of the chick leg with four digits (I-IV) arises from the polarizing region. To determine how digit identity is specified over time, we inhibited Sonic hedgehog signalling. Fate maps show that polarizing region and adjacent cells are specified in parallel through a series of anterior to posterior digit fates-a process of digit specification that we suggest is involved in patterning all vertebrate limbs with more than three digits.

  10. Three-dimensional P velocity structure of the crust and upper mantle under Beijing region

    Energy Technology Data Exchange (ETDEWEB)

    Quan, A.; Liu, F.; Sun, Y.

    1980-04-01

    By use of the teleseismic P arrival times at 15 stations of the Beijing network for 120 events distributed over various azimuths, we studied the three-dimensional P velocity structure under the Beijing region. In calculating the theoretic travel time, we adopted the source parameters given in BISC, and used the J-B model as the standard model of earth. On inversion, we adopted singular value decomposition as a generalized inversion package, which can be used for solving very large over-determined systems of equations Gm = t without resorting to normal equations G/sup T/Gm = G/sup T/t. The results are that within the crust and upper mantle under the Beijing region there are clear lateral differences. In the results obtained by use of data from 1972 to 1975, it can be seen that there are three different zones of P-velocity. In the southeast Beijing region, P velocity is lower than that of the normal model by 10 to 14% within the crust, and by 8 to 9% within the upper mantle. The northwest Beijing region is a higher-velocity zone, within which the average P-velocity is faster than that of the normal model by about 9%. It disappears after entering into the upper mantle. The central part of this region is a normal zone. On the surface, the distribution of these P velocity variations corresponds approximately to the distribution of the over-burden. But in the deeper region, the distribution of velocity variation agrees with the distribution of seismicity. It is interesting to note that the hypocenters of several major earthquakes in this region, e.g., the Sanhe-Pinggu earthquake (1679, M = 8), the Shacheng earthquake (1730, M = 6-3/4) and the Tangshan earthquake (1976, M = 7.8), are all located very close to this boundary of these P-velocity variation zones.

  11. Regionalization of Crustal and Upper Mantle Q Structure in Eastern Eurasia Using Multiple Regional Waves

    National Research Council Canada - National Science Library

    Gaherty, James; Lerner-Lam, Arthur

    2007-01-01

    We have mapped lateral variations in seismic Q in eastern Eurasia, including continental China, central Asia, Mongolia and Siberia, using high-frequency regional phases Lg and Pn, as well as long-period Rayleigh waves...

  12. Magnetic Field Perturbations from Currents in the Dark Polar Regions During Quiet Geomagnetic Conditions

    DEFF Research Database (Denmark)

    Friis-Christensen, Eigil; Finlay, Chris; Hesse, M.

    2017-01-01

    In the day-side sunlit polar ionosphere the varying and IMF dependent convection creates strong ionospheric currents even during quiet geomagnetic conditions. Observations during such times are often excluded when using satellite data to model the internal geomagneticmain field. Observations from...... the night-side or local winter during quiet conditions are, however, also influenced by variations in the IMF. In this paper we briefly review the large scale features of the ionospheric currents in the polar regions with emphasis on the current distribution during undisturbed conditions. We examine...

  13. Study of the Effect of Active Regions on the Scattering Polarization in the Solar Corona

    Science.gov (United States)

    Derouich, M.; Badruddin

    2018-03-01

    The solar photospheric/chromospheric light exciting atoms/ions is not homogeneous because of the presence of active regions (ARs). The effect of ARs on the scattering polarization at the coronal level is an important ingredient for a realistic determination of the magnetic field. This effect is usually disregarded or mixed with other effects in the sense that the degree of its importance is not well known. The aim of this paper is to study the effect of atmospheric inhomogeneities on the coronal scattering polarization. We determined quantitatively the importance of the atmospheric inhomogeneities by using given geometries of solar ARs (plages and sunspots).

  14. Physics in the GeV region with polarized targets in electron storage rings

    International Nuclear Information System (INIS)

    Holt, R.J.

    1988-01-01

    There is evidence from the D(γ,p)n reaction that the meson-exchange model is failing in the GeV region. Surprisingly, it appears that the new (Dγ,p)n data favor the energy dependence of the nuclear chromodynamics model rather that of the meson-exchange model. Application of the polarization method to electron scattering studies is in its infancy, and it is potentially a very powerful technique. The internal target method coupled with laser-driven polarized targets should represent an important tool for nuclear physics

  15. SPURS: Salinity Processes in the Upper-Ocean Regional Study: THE NORTH ATLANTIC EXPERIMENT

    Science.gov (United States)

    Lindstrom, Eric; Bryan, Frank; Schmitt, Ray

    2015-01-01

    In this special issue of Oceanography, we explore the results of SPURS-1, the first part of the ocean process study Salinity Processes in the Upper-ocean Regional Study (SPURS). The experiment was conducted between August 2012 and October 2013 in the subtropical North Atlantic and was the first of two experiments (SPURS come in pairs!). SPURS-2 is planned for 20162017 in the tropical eastern Pacific Ocean.

  16. CryoSat Mission over Polar Region: Data quality status and product evolutions

    Science.gov (United States)

    Bouffard, J.; Parrinello, T.; Féménias, P.; Fornari, M.; Scagliola, M.; Baker, S.; Brockley, D.; Mannan, R.; Hall, A.; Webb, E.; Garcia-Mondéjar, A.; Roca, M.; Mantovani, P. L.

    2015-12-01

    Over the past 20 years, satellite radar altimetry has shown its ability to revolutionize our understanding of the ocean and climate. These advances were mainly limited to ice-free regions, leaving aside large portions of Polar Regions. Launched in 2010, the polar-orbiting CryoSat Satellite was designed to measure the changes in the thickness of polar sea ice and the elevation of the ice sheets and mountain glaciers. To reach this goal, the CryoSat products have to meet the highest performance, through constant improvements of the associated Instrument Processing Facility. Since April 2015, the CryoSat ice products are generated with the Baseline C; which represents a major processor upgrade. Several improvements have been implemented belong this new Baseline, such as SAR retracker optimized for Freeboard retrieval and a coarse slant correction, which is applied directly on the stack data in conjunction with the window delay alignment. The resulting waveforms show more power and the trailing edge is modified, leading to improved L2 geophysical parameters. This paper provides an overview of the CryoSat data characteristics, assessment and exploitation over Polar Regions. In this respect, new science-oriented diagnostics have been implemented to thoroughly understand the signatures within the altimeter signals over sea-ice and land ice areas, to validate the data and therefore propose potential way of improvements for next CryoSat processing Baselines.

  17. Some like it cold: microbial transformations of mercury in polar regions

    Directory of Open Access Journals (Sweden)

    Niels Kroer

    2011-12-01

    Full Text Available The contamination of polar regions with mercury that is transported from lower latitudes as inorganic mercury has resulted in the accumulation of methylmercury (MeHg in food chains, risking the health of humans and wildlife. While production of MeHg has been documented in polar marine and terrestrial environments, little is known about the responsible transformations and transport pathways and the processes that control them. We posit that as in temperate environments, microbial transformations play a key role in mercury geochemical cycling in polar regions by: (1 methylating mercury by one of four proposed pathways, some not previously described; (2 degrading MeHg by activities of mercury resistant and other bacteria; and (3 carrying out redox transformations that control the supply of the mercuric ion, the substrate of methylation reactions. Recent analyses have identified a high potential for mercury-resistant microbes that express the enzyme mercuric reductase to affect the production of gaseous elemental mercury when and where daylight is limited. The integration of microbially mediated processes in the paradigms that describe mercury geochemical cycling is therefore of high priority especially in light of concerns regarding the effect of global warming and permafrost thawing on input of MeHg to polar regions.

  18. Orientation of Birkeland current sheets in the dayside polar region and its relationship to the IMF

    International Nuclear Information System (INIS)

    Saflekos, N.A.; Potemra, T.A.

    1980-01-01

    Vector magnetic field observations made with the three-axes magnetometer on the Triad satellite have been used to study the orientation of magnetic disturbances in the dayside polar region. These measurements were all made over the southern polar region and recorded at McMurdo, Antarctica. These disturbances are transverse to the main geomagnetic field and may be interpreted as being caused by field-aligned Birkeland current sheets consistent with Maxwell's equations. The current sheets in the regions usually associated with the morning and afternoon auroral regions are most often aligned in the geomagnetic east-west direction. The amplitudes of these 'south auroral' currents are larger in the morning than in the afternoon when the interplanetary magnetic field (IMF) is directed toward the sun (B/sub y/ 0) and larger in the afternoon when the IMF is directed away (B/sub y/>0, B/sub x/ 0 the Birkeland current flow in the region of the southern cusp is predominantly away from the ionosphere in contrast to the downward flow into the northern cusp as determined earlier (e.g., McDiarmid et al., 1978b; Iijima et al., 1978). The cusp Birkeland current flow directions appear to reverse for B/sub y/>0 and B/sub x/<0. From a search of the Triad data set, some rare examples of magnetic disturbances with a large north-south (noon-midnight) component have been discovered in the polar cap near noon

  19. To the Extremes! A Teacher Research Experience Program in the Polar Regions

    Science.gov (United States)

    Warburton, J.; Bartholow, S.

    2014-12-01

    PolarTREC-Teachers and Researchers Exploring and Collaborating, a teacher professional development program, began with the International Polar Year in 2004 and continues today in the United States. In 2007, the National Science Foundation designated PolarTREC as potentially transformative, meaning that the "research results often do not fit within established models or theories and may initially be unexpected or difficult to interpret; their transformative nature and utility might not be recognized until years later." PolarTREC brings U.S. K-12 educators and polar researchers together through an innovative teacher research experience model. Teachers spend three to six weeks in remote arctic and Antarctic field camps. Since 2007, over 100 teachers have been placed in field experiences throughout the Arctic and Antarctic and with half of them participating in field experiences in Antarctica. During their experience, teachers become research team members filling a variety of roles on the team. They also fulfil a unique role of public outreach officer, conducting live presentations about their field site and research as well as journaling, answering questions, and posting photos. Evaluation data collected over the past eight years on program participants shows that PolarTREC has clearly achieved it goals and strongly suggests programs that link teachers and researchers can have the potential to transform the nature of science education. By giving teachers the content knowledge, pedagogical tools, confidence, understanding of science in the broader society, and experiences with scientific inquiry, participating teachers are using authentic scientific research in their classrooms. Not surprisingly this has also led to increases in student interest and knowledge about the Polar Regions. In this presentation, we will highlight the best practices of teacher research experiences as well as discuss why it is vital to have teachers and researchers work together to communicate

  20. Large mammals from the Upper Neopleistocene reference sections in the Tunka rift valley, southwestern Baikal Region

    Science.gov (United States)

    Shchetnikov, A. A.; Klementiev, A. M.; Filinov, I. A.; Semeney, E. Yu.

    2015-03-01

    This work presents the data on new finds of fossil macrotheriofauna in the reference sections of the Upper Neopleistocene sediments in the Tunka rift valley (southwestern Baikal Region). The osteological material of a number of Late Neopleistocene mammals including extinct species rare for the Baikal region such as Crocuta spelaea, Panthera spelaea, and Spirocerus kiakhtensis (?) was directly dated with a radiocarbon (AMS) method. The obtained 14C data (18000-35000 years) allow one to rejuvenate significantly the upper limit of the common age interval of habitat of these animals in southern part of Eastern Siberia. Cave hyena and spiral-horned antelope lived in the Tunka rift valley in the Baikal region in Late Kargino time (37-24 ka), and cave lion survived the maximum in the Sartan cryochron in the region (21-20 ka). The study of collected paleontological collections provides a basis for selection of independent Kargino (MIS 3) faunal assemblages to use them for regional biostratigraphic analysis of Pleistocene deposits. Radiocarbon age dating of samples allows one to attribute confidently all paleofaunal remains available to the second half of the Late Pleistocene.

  1. Local extirpations and regional declines of endemic upper beach invertebrates in southern California

    Science.gov (United States)

    Hubbard, D. M.; Dugan, J. E.; Schooler, N. K.; Viola, S. M.

    2014-10-01

    Along the world's highly valued and populous coastlines, the upper intertidal zones of sandy beach ecosystems and the biodiversity that these zones support are increasingly threatened by impacts of human activities, coastal development, erosion, and climate change. The upper zones of beaches typically support invertebrates with restricted distributions and dispersal, making them particularly vulnerable to habitat loss and fragmentation. We hypothesized that disproportionate loss or degradation of these zones in the last century has resulted in declines of upper shore macroinvertebrates in southern California. We identified a suite of potentially vulnerable endemic upper beach invertebrates with direct development, low dispersal and late reproduction. Based on the availability of printed sources and museum specimens, we investigated historical changes in distribution and abundance of two intertidal isopod species (Tylos punctatus, Alloniscus perconvexus) in southern California. Populations of these isopods have been extirpated at numerous historically occupied sites: T. punctatus from 16 sites (57% decrease), and A. perconvexus from 14 sites (64% decrease). During the same period, we found evidence of only five colonization events. In addition, the northern range limit of the southern species, T. punctatus, moved south by 31 km (8% of range on California mainland) since 1971. Abundances of T. punctatus have declined on the mainland coast; only three recently sampled populations had abundances >7000 individuals m-1. For A. perconvexus populations, abundances >100 individuals m-1 now appear to be limited to the northern part of the study area. Our results show that numerous local extirpations of isopod populations have resulted in regional declines and in greatly reduced population connectivity in several major littoral cells of southern California. Two of the six major littoral cells (Santa Barbara and Zuma) in the area currently support 74% of the remaining isopod

  2. Economic Polarization Across European Union Regions in the years 2007–2012 at NUTS 2 Level

    Directory of Open Access Journals (Sweden)

    Piętak Łukasz

    2016-12-01

    Full Text Available The aim of this paper is to study the economic polarization in countries of the EU at NUTS 2 level in the years 2007–2012. The studies have to decide on positive or negative verification of the hypothesis, which states that the economic crisis of 2008–2013 had an influence on rising economic polarization in EU countries. The method used in this article is an application of some measures of economic polarization and inequality of income distribution. The carried out research did not allow for the positive verification of the hypothesis. Only in a few countries did the economic crisis have an influence on a reduction of the middle class. In most cases the economic collapse did not play any role in the raising of the economic polarization index. The statistical data used in this paper was taken from the following databases: Statistical Yearbook of the Regions – Poland from 2009 to 2013 and Eurostat – Regional statistics by NUTS classification*.

  3. Cloud Masking and Surface Temperature Distribution in the Polar Regions Using AVHRR and other Satellite Data

    Science.gov (United States)

    Comiso, Joey C.

    1995-01-01

    Surface temperature is one of the key variables associated with weather and climate. Accurate measurements of surface air temperatures are routinely made in meteorological stations around the world. Also, satellite data have been used to produce synoptic global temperature distributions. However, not much attention has been paid on temperature distributions in the polar regions. In the polar regions, the number of stations is very sparse. Because of adverse weather conditions and general inaccessibility, surface field measurements are also limited. Furthermore, accurate retrievals from satellite data in the region have been difficult to make because of persistent cloudiness and ambiguities in the discrimination of clouds from snow or ice. Surface temperature observations are required in the polar regions for air-sea-ice interaction studies, especially in the calculation of heat, salinity, and humidity fluxes. They are also useful in identifying areas of melt or meltponding within the sea ice pack and the ice sheets and in the calculation of emissivities of these surfaces. Moreover, the polar regions are unique in that they are the sites of temperature extremes, the location of which is difficult to identify without a global monitoring system. Furthermore, the regions may provide an early signal to a potential climate change because such signal is expected to be amplified in the region due to feedback effects. In cloud free areas, the thermal channels from infrared systems provide surface temperatures at relatively good accuracies. Previous capabilities include the use of the Temperature Humidity Infrared Radiometer (THIR) onboard the Nimbus-7 satellite which was launched in 1978. Current capabilities include the use of the Advance Very High Resolution Radiometer (AVHRR) aboard NOAA satellites. Together, these two systems cover a span of 16 years of thermal infrared data. Techniques for retrieving surface temperatures with these sensors in the polar regions have

  4. Ultrasound-Guided Regional Anesthesia for Procedures of the Upper Extremity

    Directory of Open Access Journals (Sweden)

    Farheen Mirza

    2011-01-01

    Full Text Available Anesthesia options for upper extremity surgery include general and regional anesthesia. Brachial plexus blockade has several advantages including decreased hemodynamic instability, avoidance of airway instrumentation, and intra-, as well as post-operative analgesia. Prior to the availability of ultrasound the risks of complications and failure of regional anesthesia made general anesthesia a more desirable option for anesthesiologists inexperienced in the practice of regional anesthesia. Ultrasonography has revolutionized the practice of regional anesthesia. By visualizing needle entry throughout the procedure, the relationship between the anatomical structures and the needle can reduce the incidence of complications. In addition, direct visualization of the spread of local anesthesia around the nerves provides instant feedback regarding the likely success of the block. This review article outlines how ultrasound has improved the safety and success of brachial plexus blocks. The advantages that ultrasound guidance provides are only as good as the experience of the anesthesiologist performing the block. For example, in experienced hands, with real time needle visualization, a supraclavicular brachial plexus block has changed from an approach with the highest risk of pneumothorax to a block with minimal risks making it the ideal choice for most upper extremity surgeries.

  5. The Venus Emissivity Mapper - Investigating the Atmospheric Structure and Dynamics of Venus' Polar Region

    Science.gov (United States)

    Widemann, T.; Marcq, E.; Tsang, C.; Mueller, N. T.; Kappel, D.; Helbert, J.; Dyar, M. D.; Smrekar, S. E.

    2017-12-01

    Venus' climate evolution is driven by the energy balance of its global cloud layers. Venus displays the best-known case of polar vortices evolving in a fast-rotating atmosphere. Polar vortices are pervasive in the Solar System and may also be present in atmosphere-bearing exoplanets. While much progress has been made since the early suggestion that the Venus clouds are H2O-H2SO4 liquid droplets (Young 1973), several cloud parameters are still poorly constrained, particularly in the lower cloud layer and optically thicker polar regions. The average particle size is constant over most of the planet but increases toward the poles. This indicates that cloud formation processes are different at latitudes greater than 60°, possibly as a result of the different dynamical regimes that exist in the polar vortices (Carlson et al. 1993, Wilson et al. 2008, Barstow et al. 2012). Few wind measurements exist in the polar region due to unfavorable viewing geometry of currently available observations. Cloud-tracking data indicate circumpolar circulation close to solid-body rotation. E-W winds decrease to zero velocity close to the pole. N-S circulation is marginal, with extremely variable morphology and complex vorticity patterns (Sanchez-Lavega et al. 2008, Luz et al. 2011, Garate-Lopez et al. 2013). The Venus Emissivity Mapper (VEM; Helbert et al., 2016) proposed for NASA's Venus Origins Explorer (VOX) and the ESA M5/EnVision orbiters has the capability to better constrain the microphysics (vertical, horizontal, time dependence of particle size distribution, or/and composition) of the lower cloud particles in three spectral bands at 1.195, 1.310 and 1.510 μm at a spatial resolution of 10 km. Circular polar orbit geometry would provide an unprecedented study of both polar regions within the same mission. In addition, VEM's pushbroom method will allow short timescale cloud dynamics to be assessed, as well as local wind speeds, using repeated imagery at 90 minute intervals

  6. Polar Polygons

    Science.gov (United States)

    2005-01-01

    18 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark-outlined polygons on a frost-covered surface in the south polar region of Mars. In summer, this surface would not be bright and the polygons would not have dark outlines--these are a product of the presence of seasonal frost. Location near: 77.2oS, 204.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  7. Snow and Ice Applications of AVHRR in Polar Regions: Report of a Workshop

    Science.gov (United States)

    Steffen, K.; Bindschadler, R.; Casassa, G.; Comiso, J.; Eppler, D.; Fetterer, F.; Hawkins, J.; Key, J.; Rothrock, D.; Thomas, R.; hide

    1993-01-01

    The third symposium on Remote Sensing of Snow and Ice, organized by the International Glaciological Society, took place in Boulder, Colorado, 17-22 May 1992. As part of this meeting a total of 21 papers was presented on snow and ice applications of Advanced Very High Resolution Radiometer (AVHRR) satellite data in polar regions. Also during this meeting a NASA sponsored Workshop was held to review the status of polar surface measurements from AVHRR. In the following we have summarized the ideas and recommendations from the workshop, and the conclusions of relevant papers given during the regular symposium sessions. The seven topics discussed include cloud masking, ice surface temperature, narrow-band albedo, ice concentration, lead statistics, sea-ice motion and ice-sheet studies with specifics on applications, algorithms and accuracy, following recommendations for future improvements. In general, we can affirm the strong potential of AVHRR for studying sea ice and snow covered surfaces, and we highly recommend this satellite data set for long-term monitoring of polar process studies. However, progress is needed to reduce the uncertainty of the retrieved parameters for all of the above mentioned topics to make this data set useful for direct climate applications such as heat balance studies and others. Further, the acquisition and processing of polar AVHRR data must become better coordinated between receiving stations, data centers and funding agencies to guarantee a long-term commitment to the collection and distribution of high quality data.

  8. Regional contamination versus regional dietary differences: Understanding geographic variation in brominated and chlorinated contaminant levels in polar bears

    Science.gov (United States)

    McKinney, M.A.; Letcher, R.J.; Aars, Jon; Born, E.W.; Branigan, M.; Dietz, R.; Evans, T.J.; Gabrielsen, G.W.; Muir, D.C.G.; Peacock, E.; Sonne, C.

    2011-01-01

    The relative contribution of regional contamination versus dietary differences to geographic variation in polar bear (Ursus maritimus) contaminant levels is unknown. Dietary variation between Alaska Canada, East Greenland, and Svalbard subpopulations was assessed by muscle nitrogen and carbon stable isotope (?? 15N, ?? 13C) and adipose fatty acid (FA) signatures relative to their main prey (ringed seals). Western and southern Hudson Bay signatures were characterized by depleted ?? 15N and ??13C, lower proportions of C20 and C22 monounsaturated FAs and higher proportions of C18 and longer chain polyunsaturated FAs. East Greenland and Svalbard signatures were reversed relative to Hudson Bay. Alaskan ?? 2011 American Chemical Society.

  9. Multi-Polarization ASAR Backscattering from Herbaceous Wetlands in Poyang Lake Region, China

    Directory of Open Access Journals (Sweden)

    Huiyong Sang

    2014-05-01

    Full Text Available Wetlands are one of the most important ecosystems on Earth. There is an urgent need to quantify the biophysical parameters (e.g., plant height, aboveground biomass and map total remaining areas of wetlands in order to evaluate the ecological status of wetlands. In this study, Environmental Satellite/Advanced Synthetic Aperture Radar (ENVISAT/ASAR dual-polarization C-band data acquired in 2005 is tested to investigate radar backscattering mechanisms with the variation of hydrological conditions during the growing cycle of two types of herbaceous wetland species, which colonize lake borders with different elevation in Poyang Lake region, China. Phragmites communis (L. Trin. is semi-aquatic emergent vegetation with vertical stem and blade-like leaves, and the emergent Carex spp. has rhizome and long leaves. In this study, the potential of ASAR data in HH-, HV-, and VV-polarization in mapping different wetland types is examined, by observing their dynamic variations throughout the whole flooding cycle. The sensitivity of ASAR backscattering coefficients to vegetation parameters of plant height, fresh and dry biomass, and vegetation water content is also analyzed for Phragmites communis (L. Trin. and Carex spp. The research for Phragmites communis (L. Trin. shows that HH polarization is more sensitive to plant height and dry biomass than HV polarization. ASAR backscattering coefficients are relatively less sensitive to fresh biomass, especially in HV polarization. However, both are highly dependent on canopy water content. In contrast, the dependence of HH- and HV- backscattering from Carex community on vegetation parameters is poor, and the radar backscattering mechanism is controlled by ground water level.

  10. Lithofacies palaeogeography of the Late Permian Wujiaping Age in the Middle and Upper Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    Jin-Xiong Luo

    2014-10-01

    Full Text Available The lithofacies palaeogeography of the Late Permian Wujiaping Age in Middle and Upper Yangtze Region was studied based on petrography and the “single factor analysis and multifactor comprehensive mapping” method. The Upper Permian Wujiaping Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks and clastic rocks, with lesser amounts of siliceous rocks, pyroclastic rocks, volcanic rocks and coal. The rocks can be divided into three types, including clastic rock, clastic rock–limestone and limestone–siliceous rock, and four fundamental ecological types and four fossil assemblages are recognized in the Wujiaping Stage. Based on a petrological and palaeoecological study, six single factors were selected, namely, thickness (m, content (% of marine rocks, content (% of shallow water carbonate rocks, content (% of biograins with limemud, content (% of thin-bedded siliceous rocks and content (% of deep water sedimentary rocks. Six single factors maps of the Wujiaping Stage and one lithofacies palaeogeography map of the Wujiaping Age were composed. Palaeogeographic units from west to east include an eroded area, an alluvial plain, a clastic rock platform, a carbonate rock platform where biocrowds developed, a slope and a basin. In addition, a clastic rock platform exists in the southeast of the study area. Hydrocarbon source rock and reservoir conditions were preliminarily analyzed based on lithofacies palaeogeography. Sedimentary environments have obvious controls over the development of the resource rocks. With regard to the abundance of organic matter, the hydrocarbon potential of the coastal swamp environment is the best, followed by the basin environment and the carbonate rock platform. The gas reservoir types of the Wujiaping Stage can be classified as conventional and unconventional gas reservoirs, like coal bed gas and shale gas; all of them have well exploration prospects.

  11. Reconstruction of the mid-Hirnantian palaeotopography in the Upper Yangtze region, South China

    Directory of Open Access Journals (Sweden)

    Linna Zhang

    2014-12-01

    Full Text Available Reconstruction of the Hirnantian (Late Ordovician palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis was used to further observe the terrain changes along two given directions.The reconstructed palaeotopographic map shows a relatively flat and shallow epicontinental sea with three local depressions and a submarine high on the Upper Yangtze region during the Hirnantian. The water depth is mostly less than 60 m and the Yangtze Sea gradually deepens towards the north.

  12. Review of meningitis surveillance data, upper West Region, Ghana 2009-2013.

    Science.gov (United States)

    Nuoh, Robert Domo; Nyarko, Kofi Mensah; Nortey, Priscilla; Sackey, Samuel Oko; Lwanga, Noora Charles; Ameme, Donne Kofi; Nuolabong, Culbert; Abdulai, Marijanatu; Wurapa, Fredrick; Afari, Edwin

    2016-01-01

    The Upper West region of Ghana is within the meningitis belt. Analysis of long term surveillance data is necessary for understanding changes in the disease occurrence. We analyzed five years of surveillance data to describe by person, place and time and to determine trends in meningitis. Meningitis surveillance data from Ghana Health Service in the Upper West Region, from 2009 to 2013 were reviewed. Data was obtained from District-Health Information Management System and line list from the Disease Control Unit. Population figures (denominators) and rainfall data were also analyzed. Within the period 980 cases of meningitis were reported in the region, 507(52%) females and 473(48%) males. The mean age of cases was 20.1years and standard deviation 18.8 years with, 77.6 %( 761/980) cases occurring in persons aged under 30 years. Children under five years were 19.3% (190/980). Attack rates ranged from 6.1/100,000 population in the Daffiama-bussei-Issa-district to 47.5/100,000 in Jirapa. Overall case fatality rate of meningitis was 12.2% with 14deaths/100,000 population. Bacterial agents were isolated from 35% (245/702) of CSF. Majority were Streptococcus pneumonia 48.2 % ( 122/258), and N. meningitides Y/W 135 40.3% (102/258). Meningitis was found to be seasonal with peaks in the dry season. Meningitis in the region is seasonal, and showed a decreasing trend. Jirapa, Lawra, Nadowli and Wa West districts had the highest burden. Control effort of the disease should focus on vaccination against streptococcus pneumonia and N. meningitis W135 especially within crowded settlements such as boarding schools.

  13. Mechanisms of impact of greenhouse gases on the Earth's ozone layer in the Polar Regions

    Science.gov (United States)

    Zadorozhny, Alexander; Dyominov, Igor

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the atmosphere including aerosol physics is used to examine the impact of the greenhouse gases CO2, CH4, and N2O on the future long-term changes of the Earth's ozone layer, in particular on its expected recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circu-lation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the North to South Poles, as well as distribution of sulphate aerosol particles and polar strato-spheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abun-dance of the greenhouse gases on the long-term changes of the Earth's ozone layer in the Polar Regions, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2, essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weak-ness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification be-gins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard

  14. Galileo multispectral imaging of the north polar and eastern limb regions of the moon

    Science.gov (United States)

    Belton, M.J.S.; Greeley, R.; Greenberg, R.; McEwen, A.; Klaasen, K.P.; Head, J. W.; Pieters, C.; Neukum, G.; Chapman, C.R.; Geissler, P.; Heffernan, C.; Breneman, H.; Anger, C.; Carr, M.H.; Davies, M.E.; Fanale, F.P.; Gierasch, P.J.; Ingersoll, A.P.; Johnson, T.V.; Pilcher, C.B.; Thompson, W.R.; Veverka, J.; Sagan, C.

    1994-01-01

    Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.

  15. Diviner lunar radiometer observations of cold traps in the moon's south polar region

    Science.gov (United States)

    Paige, D.A.; Siegler, M.A.; Zhang, J.A.; Hayne, P.O.; Foote, E.J.; Bennett, K.A.; Vasavada, A.R.; Greenhagen, B.T.; Schofield, J.T.; McCleese, D.J.; Foote, M.C.; DeJong, E.; Bills, B.G.; Hartford, W.; Murray, B.C.; Allen, C.C.; Snook, K.; Soderblom, L.A.; Calcutt, S.; Taylor, F.W.; Bowles, N.E.; Bandfield, J.L.; Elphic, R.; Ghent, R.; Glotch, T.D.; Wyatt, M.B.; Lucey, P.G.

    2010-01-01

    Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species. The diverse mixture of water and high-volatility compounds detected in the LCROSS ejecta plume is strong evidence for the impact delivery and cold-trapping of volatiles derived from primitive outer solar system bodies.

  16. Analysis of chosen urban bioclimatic conditions in Upper Silesian Industrial Region, Poland

    Science.gov (United States)

    Zimnol, Jan

    2013-04-01

    Due to the increasing urbanization, people spend more and more time in cities. Because of that fact during the last century the human bioclimatological approach had an important influence on the applied urban bioclimatology. The aim of the study was to analyze chosen thermal bioclimatic conditions in urban area of Upper Silesian Industrial Region in connection with the atmospheric circulation and air masses. The study was focused on the thermal conditions that are important for the bioclimatological research on human thermal comfort. They were the basis for making study on how to show the influence of the air masses and circulations types on frequency and variability of the chosen bioclimate indexes. That research was based on data (2004 - 2008) acquired by the Silesian University (Faculty of Earth Sciences) meteorological station located in the city of Sosnowiec (50°17'N, 19°08'E, h=263 m a.s.l.). The temperature measurements were made automatically every 10 minutes on the 2 meters above the ground level. Previous research showed that the station is a good representation of the local urban climate conditions in Upper Silesian Industrial Region. In the study the following air temperatures were taken into consideration: average day temperature, maximum day temperature, minimum day temperature and the average air temperature at 12 UTC. They were associated with atmospheric circulation types and masses typical for the region. Using the data mentioned above I conducted a classification to divide days into following objective categories: cool, cold, comfortable, hot, warm and very hot in the seasonal depiction. The final stage of the work was to find the answer to the following question: "When and how do the strong air masses and air circulations types modify bioclimatic conditions in the study area?" Answer to that question together with further results of the research will be presented on my poster.

  17. Habitat capacity for cougar recolonization in the Upper Great Lakes region.

    Science.gov (United States)

    O Neil, Shawn T; Rahn, Kasey C; Bump, Joseph K

    2014-01-01

    Recent findings indicate that cougars (Puma concolor) are expanding their range into the midwestern United States. Confirmed reports of cougar in Michigan, Minnesota, and Wisconsin have increased dramatically in frequency during the last five years, leading to speculation that cougars may re-establish in the Upper Great Lakes (UGL) region, USA. Recent work showed favorable cougar habitat in northeastern Minnesota, suggesting that the northern forested regions of Michigan and Wisconsin may have similar potential. Recolonization of cougars in the UGL states would have important ecological, social, and political impacts that will require effective management. Using Geographic Information Systems (GIS), we extended a cougar habitat model to Michigan and Wisconsin and incorporated primary prey densities to estimate the capacity of the region to support cougars. Results suggest that approximately 39% (>58,000 km2) of the study area could support cougars, and that there is potential for a population of approximately 500 or more animals. An exploratory validation of this habitat model revealed strong association with 58 verified cougar locations occurring in the study area between 2008 and 2013. Spatially explicit information derived from this study could potentially lead to estimation of a viable population, delineation of possible cougar-human conflict areas, and the targeting of site locations for current monitoring. Understanding predator-prey interactions, interspecific competition, and human-wildlife relationships is becoming increasingly critical as top carnivores continue to recolonize the UGL region.

  18. Habitat capacity for cougar recolonization in the Upper Great Lakes region.

    Directory of Open Access Journals (Sweden)

    Shawn T O Neil

    Full Text Available BACKGROUND: Recent findings indicate that cougars (Puma concolor are expanding their range into the midwestern United States. Confirmed reports of cougar in Michigan, Minnesota, and Wisconsin have increased dramatically in frequency during the last five years, leading to speculation that cougars may re-establish in the Upper Great Lakes (UGL region, USA. Recent work showed favorable cougar habitat in northeastern Minnesota, suggesting that the northern forested regions of Michigan and Wisconsin may have similar potential. Recolonization of cougars in the UGL states would have important ecological, social, and political impacts that will require effective management. METHODOLOGY/PRINCIPAL FINDINGS: Using Geographic Information Systems (GIS, we extended a cougar habitat model to Michigan and Wisconsin and incorporated primary prey densities to estimate the capacity of the region to support cougars. Results suggest that approximately 39% (>58,000 km2 of the study area could support cougars, and that there is potential for a population of approximately 500 or more animals. An exploratory validation of this habitat model revealed strong association with 58 verified cougar locations occurring in the study area between 2008 and 2013. CONCLUSIONS/SIGNIFICANCE: Spatially explicit information derived from this study could potentially lead to estimation of a viable population, delineation of possible cougar-human conflict areas, and the targeting of site locations for current monitoring. Understanding predator-prey interactions, interspecific competition, and human-wildlife relationships is becoming increasingly critical as top carnivores continue to recolonize the UGL region.

  19. Dynamics of the polar mesopause and lower thermosphere region as observed in the night airglow emissions

    International Nuclear Information System (INIS)

    Myraboe, H.K.

    1988-02-01

    This work utilizes night airglow emissions to deduce temperatures, dynamics, energetics, transport and photochemistry of the polar 80-110 km atmospheric region. The morphological behaviour of the polar 80-110 km region as seen in the night airglow emissions is best described by quasi regular to regular variations in the temperature and in the intensities of the emissions with periods ranging from minutes to a few days. Temperature amplitudes are seen from a few degrees up to ±50 K. Intensity changes up to several hundred percent may occur. Gravity waves from below are generally found to be present in the region, being responsible for much of the short period variations. The long period variations are seen to be related to circulation changes in the lower atmosphere. Stratospheric warmings are generally associated by a cooling of the 80-110 km region by a ratio approximately twice as large in amplitude as the heating at the 10 mbar level. The semidiurnal tide is found to be dominant with a peak to peak amplitude of about 5 K, in contrast to model calculations. Effects from geomagnetic phenomena on the energetics and dynamics of the region are not seen and, if present, have to be small or rare as compared to the influence from below. There is a mesopause temperature maximum at winter solstice. Pronounced differences in the day to day and seasonal behaviour of the odd oxygen associated nightglows at the North and South Pole are found. This may indicate fundamental differences at the two poles in the winter mesopause region circulation and energetics

  20. Dynamics and Morphology of Saturn’s North Polar Region During Cassini’s Final Year

    Science.gov (United States)

    Blalock, John J.; Sayanagi, Kunio M.; Ingersoll, Andrew P.; Dyudina, Ulyana A.; Ewald, Shawn; McCabe, Ryan M.; Gunnarson, Jacob; Garland, Justin; Gallego, Angelina

    2017-10-01

    We present an analysis of Saturn’s north polar region utilizing Cassini ISS images captured in visible and near-infrared wavelengths during late 2016 and 2017, including images captured during Cassini’s Grand Finale orbits. To measure the wind field in the region, we utilize the two-dimensional correlation imaging velocimetry (CIV) technique. We also calculate the relative vorticity and divergence from the wind field. To detect changes in the dynamics, we compare measurements of the wind, relative vorticity, and divergence in 2012 and 2013 with those from 2016/2017. We also compare cloud reflectivity between 2012/2013 and 2016/2017 in images that show the north pole under similar illumination conditions. To detect changes in cloud reflectivity, we utilize a Minnaert correction to calculate the zonal mean reflectivity as a function of latitude. Furthermore, we compare the winds and cloud reflectivity at several wavelengths in order to look for changes occurring at different altitudes. Our results indicate that while the dynamics of the north polar region have remained relatively stable, there have been significant morphology changes that have resulted in dramatic color changes. We hypothesize that these changes are a result of the seasonal cycle and linked to the increased production of photochemical hazes in the atmosphere. Our work has been supported by NASA PATM NNX14AK07G, NSF AAG 1212216, and NASA NESSF NNX15AQ70H.

  1. High Frequency Backscatter from the Polar and Auroral E-Region Ionosphere

    Science.gov (United States)

    Forsythe, Victoriya V.

    The Earth's ionosphere contains collisional and partially-ionized plasma. The electric field, produced by the interaction between the Earth's magnetosphere and the solar wind, drives the plasma bulk motion, also known as convection, in the F-region of the ionosphere. It can also destabilize the plasma in the E-region, producing irregularities or waves. Intermediate-scale waves with wavelengths of hundreds of meters can cause scintillation and fading of the Global Navigation Satellite System (GNSS) signals, whereas the small-scale waves (lambda Network (SuperDARN). The theoretical part of this work focuses on symmetry properties of the general dispersion relation that describes wave propagation in the collisional plasma in the two-stream and gradient-drift instability regimes. The instability growth rate and phase velocity are examined under the presence of a background parallel electric field, whose influence is demonstrated to break the spatial symmetry of the wave propagation patterns. In the observational part of this thesis, a novel dual radar setup is used to examine E-region irregularities in the magnetic polar cap by probing the E-region along the same line from opposite directions. The phase velocity analysis together with raytracing simulations demonstrated that, in the polar cap, the radar backscatter is primarily controlled by the plasma density conditions. In particular, when the E-region layer is strong and stratified, the radar backscatter properties are controlled by the convection velocity, whereas for a tilted E-layer, the height and aspect angle conditions are more important. Finally, the fundamental dependence of the E-region irregularity phase velocity on the component of the plasma convection is investigated using two new SuperDARN radars at high southern latitudes where plasma convection estimates are accurately deduced from all SuperDARN radars in the southern hemisphere. Statistical analysis is presented showing that the predominance of the

  2. On the Topological Changes of Local Hurst Exponent in Polar Regions

    Science.gov (United States)

    Consolini, G.; De Michelis, P.

    2014-12-01

    Geomagnetic activity during magnetic substorms and storms is related to the dinamical and topological changes of the current systems flowing in the Earth's magnetosphere-ionosphere. This is particularly true in the case of polar regions where the enhancement of auroral electrojet current system is responsible for the observed geomagnetic perturbations. Here, using the DMA-technique we evaluate the local Hurst exponent (H"older exponent) for a set of 46 geomagnetic observatories, widely distributed in the northern hemisphere, during one of the most famous and strong geomagnetic storm, the Bastille event, and reconstruct a sequence of polar maps showing the dinamical changes of the topology of the local Hurst exponent with the geomagnetic activity level. The topological evolution of local Hurst exponent maps is discussed in relation to the dinamical changes of the current systems flowing in the polar ionosphere. G. Consolini has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant agreement no. 313038/STORM for this research.

  3. Optical polarization maps of star-forming regions in Perseus, Taurus, and Ophiuchus

    International Nuclear Information System (INIS)

    Goodman, A.A.; Bastien, P.; Menard, F.; Myers, P.C.

    1990-01-01

    New optical linear polarization maps are presented of the star-forming regions near L1506 in Taurus, L1755 in Ophiuchus, and the complex of dark cloud which extends from L1448 in B5 in Perseus. The former two show a well-defined peak magnetic field direction in the plane of the sky with a finite dispersion about that peak which is smaller than would be expected for a random distribution of field distributions. The dispersion in the position angle of filamentary clouds within these complexes implies that clouds which appear elongated on the plane of the sky are not all associated with a pattern of polarization vectors particularly parallel or perpendicular to their geometry. Instead, clouds tend to be oriented at the angle formed by their axis and the mean direction of the local large-scale field. For the dark cloud complex, a bimodal distribution of the polarization vector angle is taken to result from at least two distributions of gas along the line of sight which appear as a complex in projection. 55 refs

  4. Principles for the establishment of upper bounds to doses to individuals from global and regional sources

    International Nuclear Information System (INIS)

    1989-01-01

    The IAEA Safety Guide, Safety Series No. 77 (1986), Principles for Limiting Releases of Radioactive Effluents into the Environment, identifies the concept of upper bounds to individual dose. They are the fractions of the dose limit for members of the public allocated to the various different sources and practices which can give rise to individual exposure. This Guide is concerned with the contributions to individual dose which may arise from other sources in the same region and also from sources which are far away but which, because of the nature of the radionuclides involved, give rise to a global component of dose. Consideration is given to the need for control of such exposures and the means by which it could be achieved. The text may be seen as providing expansion of the guidance given in Safety Series No. 77. 24 refs

  5. 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

  6. Risk of contamination of wild berries from upper Orava region by cadmium

    Directory of Open Access Journals (Sweden)

    Stanislav Zupka

    2016-01-01

    Full Text Available The upper Orava region is located at the North Slovakia, near of potential sources of environmental contamination due by mining of coal, zinc and lead ores. The aim of the study was to evaluate the risk of consumption of wild forest fruit from Upper Orava region from the aspect of cadmium content. Ten sampling points were found by random search. From these points samples of soil, leaves and fruits of wild berries (9 samples of blueberries Vaccinium Myrtillus and 1 sample of strawberries Fragaria Vesca were collected. In soil samples the active soil reaction (pH/H2O ranged from 3.53 (strong acidity to 4.56 (extremly strong acidity, and the determined percentage of humus ranged from 1.66 (low humic soil to 4.90 (high humic soil.  In two soil samples the total content of cadmium determinated in soil extracts by aqua regia exceeded limit 0.70 mg.kg-1 given by the legislation in tne Slovak Republic. In three soil samples the determined content of cadmium mobile forms determined in soil extracts by NH4NO3 exceeded the limit 0.10 mg.kg-1. The content of Cd determined in leaves as well as in fruits was evaluated according to Food Codex of the Slovak Republic. Only in one sample of leaf samples the limit 1.00 mg.kg-1 was exceeded. The other leaf samples are safely when used as an ingredient in tea mixtures. On the other hand even in 7 fruit samples the limit 0.05 mg.kg-1 was exceeded. This fruit can pose a risk for the human organism when is directly consumed as well as may negatively affect the human health when is used as raw materials in the food industry. 

  7. Mediating Data and Building Community for Informed, Intelligent Decision Making for the Polar Regions

    Science.gov (United States)

    Pulsifer, P. L.; Stieglitz, M.

    2017-12-01

    Much has been written about the state of data and related systems for the polar regions, however work remains to be done to achieve an envisioned integrated and well-defined pan-Arctic observing and data network that enables access to high quality data, expertise and information in support of scientific understanding, stakeholder needs, and agency operations. In this paper we argue that priorities for establishing such a network are in the area of machine-enhanced data mediation and the human aspects of community building. The authors have engaged in a U.S.-based, multi-agency process with the goal of applying modern cyberinfrastructure to improve capabilities for integrating data. A particular case-study focuses on establishing a carbon budget for the Arctic region. This effort contributes to broader global efforts aimed at establishing an international observing and data network. Results are based on a series meetings, workshops, systems design activities, and publications. Analysis reveals that there are a large number of polar data resources interacting in a network that functions as a data ecosystem. Given the size and complexity of the network, achieving broad data discovery and access and meaningful data integration (i.e. developing a carbon budget) will require advanced techniques including machine learning, semantic mediation, and the use of highly connected virtual research environments. To achieve the aforementioned goal will require a community of engaged researchers, technologists, and stakeholders to establish requirements and the social and organizational context needed for effective machine-based approaches. The results imply that: i) the polar research and application community must be more aware of advances in technology; ii) funders must adopt a long-term, sustainable infrastructure approach to systems development; iii) the community must work together to enable interoperability; iv) we must recognize that the challenge is socio-technical and

  8. Characterization of cosmic rays and direction dependence in the Polar Region up to 88 km altitude

    Directory of Open Access Journals (Sweden)

    Zábori Balázs

    2016-01-01

    Full Text Available Aims: The sounding rocket experiment REM-RED was developed to operate on board the REXUS-17 rocket in order to measure the intensity of cosmic rays. The experiment was launched from the ESRANGE Space Center (68 °N, 21 °E on the 17th of March 2015 at the beginning of the most intense geomagnetic storm within the preceding 10 years. The experiment provided the opportunity to measure the intensity of cosmic rays in the Polar Region up to an altitude of 88 km above sea level. Methods: The experiment employed Geiger-Müller (GM counters oriented with their axes perpendicular to each other in order to measure the cosmic ray intensity during the flight of the rocket. This measurement setup allowed performing direction-sensitive measurements as well. During the ascent phase the rocket was spinning and hence stabilized along its longitudinal axis looking close to the zenith direction. This phase of the flight was used for studying the direction dependence of the charged particle component of the cosmic rays. Results: In comparison with earlier, similar rocket experiments performed with GM tubes at lower geomagnetic latitudes, significantly higher cosmic radiation flux was measured above 50 km. A non-isotropic behavior was found below 50 km and described in detail for the first time in the Polar Region. This behavior is in good agreement with the results of the TECHDOSE experiment that used the same type of GM tubes on board the BEXUS-14 stratospheric balloon.

  9. Thermal Stability of Frozen Volatiles in the North Polar Region of Mercury

    Science.gov (United States)

    Paige, David A.; Siegler, Matthew A.; Harmon, John K.; Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.; Solomon, Sean C.

    2012-01-01

    Earth-based radar observations have revealed the presence on Mercury of anomalously bright, depolarizing features that appear to be localized in the permanently shadowed regions of high-latitude impact craters [1]. Observations of similar radar signatures over a range of radar wavelengths implies that they correspond to deposits that are highly transparent at radar wavelengths and extend to depths of several meters below the surface [1]. Thermal models using idealized crater topographic profiles have predicted the thermal stability of surface and subsurface water ice at these same latitudes [2]. One of the major goals of the MESSENGER mission is to characterize the nature of radar-bright craters and presumed associated frozen volatile deposits at the poles of Mercury through complementary orbital observations by a suite of instruments [3]. Here we report on an examination of the thermal stability of water ice and other frozen volatiles in the north polar region of Mercury using topographic profiles obtained by the Mercury Laser Altimeter (MLA) instrument [4] in conjunction with a three-dimensional ray-tracing thermal model previously used to study the thermal environment of polar craters on the Moon [5].

  10. Pitch Angle Scattering of Upgoing Electron Beams in Jupiter's Polar Regions by Whistler Mode Waves

    Science.gov (United States)

    Elliott, S. S.; Gurnett, D. A.; Kurth, W. S.; Clark, G.; Mauk, B. H.; Bolton, S. J.; Connerney, J. E. P.; Levin, S. M.

    2018-02-01

    The Juno spacecraft's Jupiter Energetic-particle Detector Instrument has observed field-aligned, unidirectional (upgoing) electron beams throughout most of Jupiter's entire polar cap region. The Waves instrument detected intense broadband whistler mode emissions occurring in the same region. In this paper, we investigate the pitch angle scattering of the upgoing electron beams due to interactions with the whistler mode waves. Profiles of intensity versus pitch angle for electron beams ranging from 2.53 to 7.22 Jovian radii show inconsistencies with the expected adiabatic invariant motion of the electrons. It is believed that the observed whistler mode waves perturb the electron motion and scatter them away from the magnetic field line. The diffusion equation has been solved by using diffusion coefficients which depend on the magnetic intensity of the whistler mode waves.

  11. Three decades of BGR airborne geophysical surveys over the polar regions - a review

    Science.gov (United States)

    Damaske, Detlef

    2013-04-01

    The Federal Institute for Geosciences and Natural Resources (BGR) has been conducting geological polar research since 1979. A few years later BGR engaged in airborne geophysical projects. Investigation of the lithosphere of the continent and the continental margins was one of the key issues for BGR. Right from the beginning geophysical research was closely associated with the geological activities. The GANOVEX (German Antarctic North Victoria Land Expedition) program combined geological research with geophysical (mainly airborne) investigations. This proved to be a fruitful approach to many of the open questions regarding the tectonic development of the Ross Sea region. Aeromagnetic surveys evolved into a powerful tool for identifying geological structures and following them underneath the ice covered areas - not accessible to direct geological investigations. To achieve this aim it was essential to lay out these surveys with a relatively closely spaced line separation on the expense of covering large areas at the same time. Nevertheless, over many years of continues research areas of more than a just regional extent could be covered. This was, however, only possible through international collaboration. During the first years, working in the Ross Sea area, the cooperation with the US and Italian programs played a significant role, especially the GITARA (German-Italian Aeromagnetic Research in Antarctica) program has to be mentioned. GEOMAUD (Geoscientific Expedition to Dronning Maud Land) and the German-Australian joint venture PCMEGA (Prince Charles Mountains Expedition of Germany & Australia) expanded research activities to the East Antarctic shield area. In the International Polar Year (IPY), BGR played a leading role in the international project AGAP (Antarctica's GAmburtsev Province) as part of the main topic "Venture into Unknown Regions". AGAP was jointly conducted by the USA, Great Britain, Australia, China and Germany. While in the Ross Sea area even

  12. Polarization Properties and Magnetic Field Structures in the High-mass Star-forming Region W51 Observed with ALMA

    Science.gov (United States)

    Koch, Patrick M.; Tang, Ya-Wen; Ho, Paul T. P.; Yen, Hsi-Wei; Su, Yu-Nung; Takakuwa, Shigehisa

    2018-03-01

    We present the first ALMA dust polarization observations toward the high-mass star-forming regions W51 e2, e8, and W51 North in Band 6 (230 GHz) with a resolution of about 0\\buildrel{\\prime\\prime}\\over{.} 26 (∼5 mpc). Polarized emission in all three sources is clearly detected and resolved. Measured relative polarization levels are between 0.1% and 10%. While the absolute polarization shows complicated structures, the relative polarization displays the typical anticorrelation with Stokes I, although with a large scatter. Inferred magnetic (B) field morphologies are organized and connected. Detailed substructures are resolved, revealing new features such as comet-shaped B-field morphologies in satellite cores, symmetrically converging B-field zones, and possibly streamlined morphologies. The local B-field dispersion shows some anticorrelation with the relative polarization. Moreover, the lowest polarization percentages together with largest dispersions coincide with B-field convergence zones. We put forward \\sin ω , where ω is the measurable angle between a local B-field orientation and local gravity, as a measure of how effectively the B field can oppose gravity. Maps of \\sin ω for all three sources show organized structures that suggest a locally varying role of the B field, with some regions where gravity can largely act unaffectedly, possibly in a network of narrow magnetic channels, and other regions where the B field can work maximally against gravity.

  13. Vegetation Dynamics in the Upper Guinean Forest Region of West Africa from 2001 to 2015

    Directory of Open Access Journals (Sweden)

    Zhihua Liu

    2016-12-01

    Full Text Available The Upper Guinea Forest (UGF region of West Africa is one of the most climatically marginal and human-impacted tropical forest regions in the world. Research on the patterns and drivers of vegetation change is critical for developing strategies to sustain ecosystem services in the region and to understand how climate and land use change will affect other tropical forests around the globe. We compared six spectral indices calculated from the 2001–2015 MODIS optical-infrared reflectance data with manually-interpreted measurements of woody vegetation cover from high resolution imagery. The tasseled cap wetness (TCW index was found to have the strongest association with woody vegetation cover, whereas greenness indices, such as the enhanced vegetation index (EVI, had relatively weak associations with woody cover. Trends in woody vegetation cover measured with the TCW index were analyzed using Mann–Kendall statistics and were contrasted with trends in vegetation greenness measured with EVI. In the drier West Sudanian Savanna and Guinean Forest-Savanna Mosaic ecoregions, EVI trends were primarily positive, and TCW trends were primarily negative, suggesting that woody vegetation cover was decreasing, while herbaceous vegetation cover is increasing. In the wettest tropical forests in the Western Guinean Lowland Forest ecoregion, declining trends in both TCW and EVI were indicative of widespread forest degradation resulting from human activities. Across all ecoregions, declines in woody cover were less prevalent in protected areas where human activities were restricted. Multiple lines of evidence suggested that human land use and resource extraction, rather than climate trends or short-term climatic anomalies, were the predominant drivers of recent vegetation change in the UGF region of West Africa.

  14. SOLAR CYCLE VARIATIONS OF THE RADIO BRIGHTNESS OF THE SOLAR POLAR REGIONS AS OBSERVED BY THE NOBEYAMA RADIOHELIOGRAPH

    Energy Technology Data Exchange (ETDEWEB)

    Nitta, Nariaki V.; DeRosa, Marc L. [Lockheed Martin Advanced Technology Center, Dept/A021S, B/252, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Sun, Xudong; Hoeksema, J. Todd [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States)

    2014-01-10

    We have analyzed daily microwave images of the Sun at 17 GHz obtained with the Nobeyama Radioheliograph (NoRH) in order to study the solar cycle variations of the enhanced brightness in the polar regions. Unlike in previous works, the averaged brightness of the polar regions is obtained from individual images rather than from synoptic maps. We confirm that the brightness is anti-correlated with the solar cycle and that it has generally declined since solar cycle 22. Including images up to 2013 October, we find that the 17 GHz brightness temperature of the south polar region has decreased noticeably since 2012. This coincides with a significant decrease in the average magnetic field strength around the south pole, signaling the arrival of solar maximum conditions in the southern hemisphere more than a year after the northern hemisphere. We do not attribute the enhanced brightness of the polar regions at 17 GHz to the bright compact sources that occasionally appear in synthesized NoRH images. This is because they have no correspondence with small-scale bright regions in images from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory with a broad temperature coverage. Higher-quality radio images are needed to understand the relationship between microwave brightness and magnetic field strength in the polar regions.

  15. Average thermospheric wind patterns over the polar regions, as observed by CHAMP

    Directory of Open Access Journals (Sweden)

    H. Lühr

    2007-06-01

    Full Text Available Measurements of the CHAMP accelerometer are utilized to investigate the average thermospheric wind distribution in the polar regions at altitudes around 400 km. This study puts special emphasis on the seasonal differences in the wind patterns. For this purpose 131 days centered on the June solstice of 2003 are considered. Within that period CHAMP's orbit is precessing once through all local times. The cross-track wind estimates of all 2030 passes are used to construct mean wind vectors for 918 equal-area cells. These bin averages are presented in corrected geomagnetic coordinates. Both hemispheres are considered simultaneously providing summer and winter responses for the same prevailing geophysical conditions. The period under study is characterized by high magnetic activity (Kp=4− but moderate solar flux level (F10.7=124. Our analysis reveals clear wind features in the summer (Northern Hemisphere. Over the polar cap there is a fast day-to-night flow with mean speeds surpassing 600 m/s in the dawn sector. At auroral latitudes we find strong westward zonal winds on the dawn side. On the dusk side, however, an anti-cyclonic vortex is forming. The dawn/dusk asymmetry is attributed to the combined action of Coriolis and centrifugal forces. Along the auroral oval the sunward streaming plasma causes a stagnation of the day-to-night wind. This effect is particularly clear on the dusk side. On the dawn side it is evident only from midnight to 06:00 MLT. The winter (Southern Hemisphere reveals similar wind features, but they are less well ordered. The mean day-to-night wind over the polar cap is weaker by about 35%. Otherwise, the seasonal differences are mainly confined to the dayside (06:00–18:00 MLT. In addition, the larger offset between geographic and geomagnetic pole in the south also causes hemispheric differences of the thermospheric wind distribution.

  16. Average thermospheric wind patterns over the polar regions, as observed by CHAMP

    Directory of Open Access Journals (Sweden)

    H. Lühr

    2007-06-01

    Full Text Available Measurements of the CHAMP accelerometer are utilized to investigate the average thermospheric wind distribution in the polar regions at altitudes around 400 km. This study puts special emphasis on the seasonal differences in the wind patterns. For this purpose 131 days centered on the June solstice of 2003 are considered. Within that period CHAMP's orbit is precessing once through all local times. The cross-track wind estimates of all 2030 passes are used to construct mean wind vectors for 918 equal-area cells. These bin averages are presented in corrected geomagnetic coordinates. Both hemispheres are considered simultaneously providing summer and winter responses for the same prevailing geophysical conditions. The period under study is characterized by high magnetic activity (Kp=4− but moderate solar flux level (F10.7=124. Our analysis reveals clear wind features in the summer (Northern Hemisphere. Over the polar cap there is a fast day-to-night flow with mean speeds surpassing 600 m/s in the dawn sector. At auroral latitudes we find strong westward zonal winds on the dawn side. On the dusk side, however, an anti-cyclonic vortex is forming. The dawn/dusk asymmetry is attributed to the combined action of Coriolis and centrifugal forces. Along the auroral oval the sunward streaming plasma causes a stagnation of the day-to-night wind. This effect is particularly clear on the dusk side. On the dawn side it is evident only from midnight to 06:00 MLT. The winter (Southern Hemisphere reveals similar wind features, but they are less well ordered. The mean day-to-night wind over the polar cap is weaker by about 35%. Otherwise, the seasonal differences are mainly confined to the dayside (06:00–18:00 MLT. In addition, the larger offset between geographic and geomagnetic pole in the south also causes hemispheric differences of the thermospheric wind distribution.

  17. Bouncing continents: insights into the physics of the polar regions of the Earth from the POLENET project in the International Polar Year

    International Nuclear Information System (INIS)

    Reading, Anya M

    2008-01-01

    When ice sheets melt, and reduce the load on the surface of the Earth, the land areas beneath them bounce back up. New, accurate observations are needed to investigate this uplift and its implications effectively. This article provides a topical starting point for investigating some applications of physics applied to the polar regions of the Earth, and interaction between the solid Earth, ice and oceans

  18. Source-to-sink cycling of aeolian sediment in the north polar region of Mars

    Science.gov (United States)

    Ewing, R. C.; Kocurek, G.

    2012-12-01

    Aeolian sand dunes are prominent features on the landscapes of Earth, Mars, Venus and Titan and sedimentary deposits interpreted as aeolian in origin are found in the rock records of Earth and Mars. The widespread occurrence of aeolian dunes on the surface of these worlds and within their deep-time depositional records suggests that aeolian systems are and likely have been a default depositional environment for the Solar System. Within an aeolian source-to-sink context, we hypothesize that planet-specific boundary conditions strongly impact production, transport, accumulation and preservation of aeolian sediment, whereas dunes and dune-field patterns remain largely similar. This hypothesis is explored within the north polar region of Mars, which hosts the most extensive aeolian dune fields and aeolian sedimentary deposits yet recognized on Mars and appears to be a region of dynamic source-to-sink cycling of aeolian sediments. The Planum Boreum Cavi Unit rests beneath north polar ice cap of Mars and is composed of several hundred meters of niveo-aeolian dune cross-stratification. The overall architecture of the unit consists of sets of preserved dune topography with an upward increase in the abundance of ice. Dune sets are defined by stabilized, polygonally fractured bounding surfaces, erosional bounding surfaces and typical internal lee foresets made of sediment and ice. The accumulation of the Cavi Unit is interpreted as occurring through freezing and serves as an example of a cold temperature boundary condition on aeolian sediment accumulation. Preservation of the Cavi Unit arises because of deposition of the overlying ice cap and contrasts with preservation of aeolian sediment on Earth, which is largely driven by eustasy and tectonics. The Cavi Unit is thought to be one source of sediment for the north polar Olympia Undae Dune Field. The region of Olympia Undae near the Cavi Unit shows a reticulate dune field pattern composed of two sets of nearly orthogonal

  19. Polarized dependence of nonlinear susceptibility in a single layer graphene system in infrared region

    Energy Technology Data Exchange (ETDEWEB)

    Solookinejad, G., E-mail: ghsolooki@gmail.com

    2016-09-15

    In this study, the linear and nonlinear susceptibility of a single-layer graphene nanostructure driven by a weak probe light and an elliptical polarized coupling field is discussed theoretically. The Landau levels of graphene can be separated in infrared or terahertz regions under the strong magnetic field. Therefore, by using the density matrix formalism in quantum optic, the linear and nonlinear susceptibility of the medium can be derived. It is demonstrated that by adjusting the elliptical parameter, one can manipulate the linear and nonlinear absorption as well as Kerr nonlinearity of the medium. It is realized that the enhanced Kerr nonlinearity can be possible with zero linear absorption and nonlinear amplification at some values of elliptical parameter. Our results may be having potential applications in quantum information science based on Nano scales devices.

  20. 3 mm GMVA Observations of Total and Polarized Emission from Blazar and Radio Galaxy Core Regions

    Directory of Open Access Journals (Sweden)

    Carolina Casadio

    2017-10-01

    Full Text Available We present total and linearly polarized 3 mm Global mm-VLBI Array (GMVA; mm-VLBI: Very Long Baseline Interferometry observations at millimetre wavelengths images of a sample of blazars and radio galaxies from the VLBA-BU-BLAZAR 7 mm monitoring program designed to probe the innermost regions of active galactic nuclei (AGN jets and locate the sites of gamma-ray emission observed by the Fermi-LAT. The lower opacity at 3 mm and improved angular resolution—on the order of 50 microarcseconds—allow us to distinguish features in the jet not visible in the 7 mm VLBA data. We also compare two different methods used for the calibration of instrumental polarisation and we analyze the resulting images for some of the sources in the sample.

  1. The Polar Cusp

    International Nuclear Information System (INIS)

    Holtet, J.A.; Egeland, A.

    1985-01-01

    The upper atmosphere at high latitudes is often called the ''earth's window to outer space.'' Through various electrodynamic coupling processes, as well as direct transfer of particles, many of the geophysical effects displayed are direct manifestations of phenomena occurring in deep space. The high latitude ionosphere also exerts a feedback on the regions of the magnetosphere and atmosphere to which it is coupled. Of particular interest are the sections of the near space known as the Polar Cusp. A vast portion of the Earth's magnetic field envelope is electrically connected to these regions. This geometry results in a spatial mapping of the magnetospheric processes and a focusing on the ionosphere. In the Polar Cusps, the solar wind plasma also has direct access to the upper atmosphere

  2. Regional-scale controls on dissolved nitrous oxide in the Upper Mississippi River

    Science.gov (United States)

    Turner, P.A.; Griffis, T.J.; Baker, J.M.; Lee, X.; Crawford, John T.; Loken, Luke C.; Venterea, R.T.

    2016-01-01

    The U.S. Corn Belt is one of the most intensive agricultural regions of the world and is drained by the Upper Mississippi River (UMR), which forms one of the largest drainage basins in the U.S. While the effects of agricultural nitrate (NO3-) on water quality in the UMR have been well documented, its impact on the production of nitrous oxide (N2O) has not been reported. Using a novel equilibration technique, we present the largest data set of freshwater dissolved N2O concentrations (0.7 to 6 times saturation) and examine the controls on its variability over a 350 km reach of the UMR. Driven by a supersaturated water column, the UMR was an important atmospheric N2O source (+68 mg N2ONm-2 yr-1) that varies nonlinearly with the NO3-concentration. Our analyses indicated that a projected doubling of the NO3-concentration by 2050 would cause dissolved N2O concentrations and emissions to increase by about 40%.

  3. Study on 3-D velocity structure of crust and upper mantle in Sichuan-yunnan region, China

    Science.gov (United States)

    Wang, C.; Mooney, W.D.; Wang, X.; Wu, J.; Lou, H.; Wang, F.

    2002-01-01

    Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others appear the characteristic of tectonic boundary, indicating that the faults litely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the Sichuan-Yunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the Indian and the Asian plates. The crustal velocity in the Sichuan-Yunnan rhombic block generally shows normal.value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below.

  4. UPPER JURASSIC OUTCROPS ALONG THE CALDAS DA RAINHA DIAPIR, WEST CENTRAL PORTUGAL: A REGIONAL GEOHERITAGE OVERVIEW

    Directory of Open Access Journals (Sweden)

    JORGE DINIS

    2004-03-01

    Full Text Available The Mesozoic Portuguese geological heritage is very rich and varied, a legacy of the position in the western margin of Iberia and its relationship with the evolution of the North Atlantic, with an interesting tectonic history since the Late Triassic. Regarding the Upper Jurassic several connections can be established between the tectonics and the stratigraphic record in the area surrounding the Caldas da Rainha structure: the basement and salt pillow control on deposition; the beginning of a diapiric and magmatic cycle associated to the on-set of sea-floor and the exhumation of both Jurassic deposits and the core of their controlling diapirs. The nature of the outcrops and richness in sedimentary environments, related with the different phases of rifting, is a remarkable case for extensional basin studies. Geological sites can be of regional, national or international importance due to scientific, educational, economical, social or historical reasons. The present proposal can be considered as a model for the establishment of tourist/educational routes with a strong component in communication on Earth Sciences, integrating social and historical aspects at a regional level. The recognition of those sites as geoheritage may contribute to a more sustainable management, in particular because it allows the achievement of a critical dimension for the investment in human resources and marketing. In Portugal, recent legal evolution might be considered promising. Nevertheless, since implementation of the concept of protected site depends on the approval of detailed management programs, there are frequent delays, misinterpretations and disrespect of legislation. The strategy to be adopted must integrate conservation, scientific studies and science communication in projects with economic and social interest.

  5. Density heterogeneity of the upper mantle beneath Siberia from satellite gravity and a new regional crustal model

    DEFF Research Database (Denmark)

    Herceg, Matija; Thybo, Hans; Artemieva, Irina

    2013-01-01

    We present a new regional model for the density structure of the upper mantle below Siberia. The residual mantle gravity anomalies are based on gravity data derived from the GOCE gravity gradients and geopotential models, with crustal correction to the gravity field being calculated from a new...... on regional and global crustal models. We analyze how uncertainties and errors in the crustal model propagate from crustal densities to mantle residual gravity anomalies and the density model of the upper mantle. The new regional density model for the Siberian craton and the West Siberian Basin complements...... regional crustal model. This newly compiled database on the crustal seismic structure, complemented by additional constraints from petrological analysis of near-surface rocks and lower crustal xenoliths, allows for a high-resolution correction of the crustal effects as compared to previous studies based...

  6. A pilot application of regional scale risk assessment to the forestry management of the upper Grand Ronde watershed, Oregon

    Science.gov (United States)

    Suzanne M. Anderson; Wayne G. Landis

    2012-01-01

    An issue in forestry management has been the integration of a variety of different information into a threat analysis or risk assessment. In this instance, regional scale risk assessment was applied to the Upper Grande Ronde watershed in eastern Oregon to examine the potential of risk assessment for use in the management of broad landscapes. The site was a focus of...

  7. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  8. Versatality of supraclavicular flap in neck, face, and upper chest region coverage

    International Nuclear Information System (INIS)

    Almas, D.; Masood, T.; Dar, M.F.; Noman, B.

    2015-01-01

    The objective is to analyze the utility of the island supraclavicular flap in a region where skin graft cannot be used and free flap is not feasible. We assessed complications and functional outcomes. Study Design: Prospective descriptive study. Place and Duration of Study: The study was done at plastic and reconstructive surgery department CMH Rawalpindi during the period of 03 year from October 2011 to October 2014. Material and Patients: An island supraclavicular artery flap was used to reconstruct oncologic, and post burn neck contractures release defects. 30 patients were included in the study. Doppler probe was used to help with localization of vascular pedicle. All the patients with scarring in both shoulder regions, history of radiation to neck and undergoing radical neck dissection were excluded. Results: A total of 30 patients were included 20 (66.6%) male and 10 (33.3%) were female. Oncologicre section was followed by immediate reconstruction with island supraclavicular artery flap. Post burn contractures were released and covered by a pedicled supraclavicular artery flap. The recipient sites were neck, face, oral and upper chest region. The average harvest time was 1 and half hour. Donor site was closed primarily in 22 (73.3%) while 8 (26.6%) require skin grafting. Post burn contractures needed scar management with intralesional steroid, pressure garments and scar revision with Z-plasty in 4(13.3%) cases. 1 (3.3%) flap failed completely and the defect was covered with a skin graft. We had 01 (3.3%) mortality due to respiratory obstruction, despite adequate flap perfusion for 24 hours. Minor complications included, partial flap loss, seroma, and haematoma formation. In addition hypertrophied scar, spreading scar and keloid formation occurred at the donor site 18 (60%). Conclusion: Island supraclavicular artery flap with an easy learning curve is a reliable flap. It has a good colour and texture match with minimal donor site morbidity. It is an excellent

  9. ARCAD3-SAFARI coordinated study of auroral and polar F-region ionospheric irregularities

    International Nuclear Information System (INIS)

    Villain, J.P.; Hanuise, C.; Beghin, C.

    1985-01-01

    Simultaneous observations of F-region ionospheric irregularities have been performed with the SAFARI ground based HF radars and the ISOPROBE experiment on board the AUREOL-3 satellite. Among seven orbits during which the satellite trajectory was directly in the radar beam or in the vicinity, four of them have been analysed in detail. The spectral power of the electron density variations ΔNe/Ne has been calculated for wavelengths between 20 m and 1 km from the ISOPROBE high time resolution thermal plasma measurements. One spectrum is obtained every 1.2 sec., which corresponds to about 10 km along the satellite trajectory. The SAFARI experiment is a set of two HF coherent radars located at Lycksele (Sweden) and Oulu (Finland). These radars are sensitive to F-region ionospheric irregularities of 10 m wavelength in the polar and auroral ionosphere. The phase velocity of the irregularities obtained from the Doppler spectrum is related to the ambient plasma drift. The presence of echoes observed with the SAFARI radars is compared with the spectral power of the electron density variations deduced from the ISOPROBE in-situ measurements. A good agreement is found between the two sets of observations and a numerical value of the spectral power corresponding to detection of echoes by the radar is given. A synoptical view of the event is given and interpreted according to the existing theories on plasma irregularities

  10. Integrating multiscale polar active contours and region growing for microcalcifications segmentation in mammography

    International Nuclear Information System (INIS)

    Arikidis, N S; Karahaliou, A; Skiadopoulos, S; Panagiotakis, G; Costaridou, L; Likaki, E

    2009-01-01

    Morphology of individual microcalcifications is an important clinical factor in microcalcification clusters diagnosis. Accurate segmentation remains a difficult task due to microcalcifications small size, low contrast, fuzzy nature and low distinguishability from surrounding tissue. A novel application of active rays (polar transformed active contours) on B-spline wavelet representation is employed, to provide initial estimates of microcalcification boundary. Then, a region growing method is used with pixel aggregation constrained by the microcalcification boundary estimates, to obtain the final microcalcification boundary. The method was tested on dataset of 49 microcalcification clusters (30 benign, 19 malignant), originating from the DDSM database. An observer study was conducted to evaluate segmentation accuracy of the proposed method, on a 5-point rating scale (from 5:excellent to 1:very poor). The average accuracy rating was 3.98±0.81 when multiscale active rays were combined to region growing and 2.93±0.92 when combined to linear polynomial fitting, while the difference in rating of segmentation accuracy was statistically significant (p < 0.05).

  11. Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort Sea and neighboring regions, Alaska, 1910-2010

    Science.gov (United States)

    Durner, George M.; Fischbach, Anthony S.; Amstrup, Steven C.; Douglas, David C.

    2010-01-01

    This report presents data on the approximate locations and methods of discovery of 392 polar bear (Ursus maritimus) maternal dens found in the Beaufort Sea and neighboring regions between 1910 and 2010 that are archived by the U.S. Geological Survey, Alaska Science Center, Anchorage, Alaska. A description of data collection methods, biases associated with collection method, primary time periods, and spatial resolution are provided. Polar bears in the Beaufort Sea and nearby regions den on both the sea ice and on land. Standardized VHF surveys and satellite radio telemetry data provide a general understanding of where polar bears have denned in this region over the past 3 decades. Den observations made during other research activities and anecdotal reports from other government agencies, coastal residents, and industry personnel also are reported. Data on past polar bear maternal den locations are provided to inform the public and to provide information for natural resource agencies in planning activities to avoid or minimize interference with polar bear maternity dens.

  12. Using isotope techniques to assess groundwater resources in the upper Jezireh region

    International Nuclear Information System (INIS)

    Kattan, Z.; Abou Zakhem, B.; Al-Charideh, A.; Kadkoy, N

    2008-07-01

    This work discuses in details the hydrochemical and environmental isotopes ( 2 H, 3 H, 13 C, 14 C, 18 O and 34 S) characteristics of groundwaters resources in the Palaeogene aquifer in the Upper Syrian Jezireh Region in order to evaluate these resources in terms of recharge zones and water ages in such an aquifer system that undergone during the last decades to intensive exploitation as a consequence of sever pumping in both Syria and Turkey. The results show that the main recharge zones for the Palaeogene aquifer exists in Turkey within lands of more than 700 m.a.s.l, and effectively coincide well with the exposure of the Karstified Nummulitic limestone in Mardin uplift. The chemical and isotopic behaviors of groundwaters, together with the radiometric 14 C ages reflect the existence of three different groundwater groups: (1) the fresh and cold water, percolating in short and shallow flow paths, such as the case of the major cold springs in Ras Al-Ain and Ain El-Arous areas and most wells located in the vicinity of the Syrian-Turkish borders, for which the main replenishment processes were occurred after the palaeoclimatic humid conditions of the Holocene period, placed between 4.5-6 ka BP; (2) the brackish and thermal waters containing certain amounts of H 2 S gas, that percolate in longer and deeper flow paths, for which the main replenishment processes were occurred during the palaeoclimatic humid conditions of the Pleistocene time, placed at 9-18 ka BP; (3) the brackish and admixed thermal groundwaters with intermediate 14 C ages, which seem to be formed as a result of mixing between the previous two groups. (Authors)

  13. Spatial and socio-demographic determinants of contraceptive use in the Upper East region of Ghana.

    Science.gov (United States)

    Achana, Fabian Sebastian; Bawah, Ayaga A; Jackson, Elizabeth F; Welaga, Paul; Awine, Timothy; Asuo-Mante, Eric; Oduro, Abraham; Awoonor-Williams, John Koku; Phillips, James F

    2015-04-02

    This paper presents results of baseline data on the determinants of contraceptive use in 7 districts in northern Ghana where there is an ongoing integrated primary health care systems strengthening projectknown as the Ghana Essential Health Intervention Project (GEHIP). We used a household survey data conducted within 66 randomly sampled census enumeration areas in seven rural districts of the Upper East Region of northern Ghana where health systems strengthening interventions are currently ongoing in three of the districts with four of the districts serving as comparison districts. This survey was conducted prior to the introduction of interventions. Data was collected on various indices included geographic information systems (GIS) and contraceptive use. The data was analyzed using survey design techniques that accounts for correct variance estimation. Categorical variables were summarized as proportions and associations between these variables and contraceptive use tested using Chi-square test. Uni-variable and multivariable logistic regression techniques were used to assess the effects of the selected covariates on contraceptive use. All tests were deemed to be statistically significant at 5% level statistical significance. Results show that contraceptive use is generally low (about 13 per cent) and use is nearly evenly for spacing and stopping purposes. Factors associated with the use of contraceptives include exposure to integrated primary healthcare services, the level of education, and socioeconomic status, couple fertility preference, marital status, and parity. For instance, the odds of contraceptive use among 15-45 year old women who live 2 km or more from a CHPS compound is 0.74 compared to women who live less than 2 km from a CHPS compound (p-value = 0.035). The findings suggest that rapid scale up of the Community based Health Planning and Services (CHPS) program accompanied with improved door-to-door health services would kindle uptake of modern

  14. LINEAR POLARIZATION OF CLASS I METHANOL MASERS IN MASSIVE STAR-FORMING REGIONS

    International Nuclear Information System (INIS)

    Kang, Ji-hyun; Byun, Do-Young; Kim, Kee-Tae; Kim, Jongsoo; Lyo, A-Ran; Vlemmings, W. H. T.

    2016-01-01

    Class I methanol masers are found to be good tracers of the interaction between outflows from massive young stellar objects with their surrounding media. Although polarization observations of Class II methanol masers have been able to provide information about magnetic fields close to the central (proto)stars, polarization observations of Class I methanol masers are rare, especially at 44 and 95 GHz. We present the results of linear polarization observations of 39 Class I methanol maser sources at 44 and 95 GHz. These two lines are observed simultaneously with one of the 21 m Korean VLBI Network telescopes in single-dish mode. Approximately 60% of the observed sources have fractional polarizations of a few percent in at least one transition. This is the first reported detection of linear polarization of the 44 GHz methanol maser. The two maser transitions show similar polarization properties, indicating that they trace similar magnetic environments, although the fraction of the linear polarization is slightly higher at 95 GHz. We discuss the association between the directions of polarization angles and outflows. We also discuss some targets having different polarization properties at both lines, including DR21(OH) and G82.58+0.20, which show the 90° polarization angle flip at 44 GHz.

  15. On transient events in the upper atmosphere generated away of thunderstorm regions

    Science.gov (United States)

    Morozenko, V.; Garipov, G.; Khrenov, B.; Klimov, P.; Panasyuk, M.; Sharakin, S.; Zotov, M.

    2011-12-01

    Experimental data on transient events in UV and Red-IR ranges obtained in the MSU missions "Unversitetsky-Tatiana" (wavelengths 300-400 nm) and "Unversitetsky-Tatiana-2" (wavelengths 300-400 nm and 600-800 nm), published by Garipov et al, in 2010 at COSPAR session http://www.cospar2010.org, at TEPA conference http://www.aragats.am/Conferences/tepa2010 and in 2011 by Sadovnichy et al, Solar System Research, 45, #1, 3-29 (2011); Vedenkin et al, JETP, v. 140, issue 3(9), 1-11 (2011) demonstrated existence of transients at large distances (up to thousands km) away of cloud thunderstorm regions. Those "remote" transients are short (1-5 msec) and are less luminous than the transients above thunderstorm regions. The ratio of Red-IR to UV photon numbers in those transients indicates high altitude of their origin (~70 km). Important observation facts are also: 1. a change of the exponent in transient distribution on luminosity Q ("-1" for photon numbers Q=1020 -1023 to "-2" for Q>1023), 2. a change of global distribution of transient with their luminosity (transients with Q>1023 are concentrated in equatorial range above continents, while transients with low luminosity are distributed more uniformly), 3. a phenomenon of transient sequences in one satellite orbit which is close to geomagnetic meridian. In the present paper phenomenological features of transients are explained in assumption that the observed transients have to be divided in two classes: 1. transients related to local, lower in the atmosphere, lightning at distance not more than hundreds km from satellite detector field of view in the atmosphere and 2. transients generated by far away lightning. Local transients are luminous and presumably are events called "transient luminous events" (TLE). In distribution on luminosity those events have some threshold Q~1023 and their differential luminosity distribution is approximated by power law exponent "-2". Remote transients have to be considered separately. Their

  16. Invited review: climate change impacts in polar regions: lessons from Antarctic moss bank archives.

    Science.gov (United States)

    Royles, Jessica; Griffiths, Howard

    2015-03-01

    Mosses are the dominant plants in polar and boreal regions, areas which are experiencing rapid impacts of regional warming. Long-term monitoring programmes provide some records of the rate of recent climate change, but moss peat banks contain an unrivalled temporal record of past climate change on terrestrial plant Antarctic systems. We summarise the current understanding of climatic proxies and determinants of moss growth for contrasting continental and maritime Antarctic regions, as informed by 13C and 18O signals in organic material. Rates of moss accumulation are more than three times higher in the maritime Antarctic than continental Antarctica with growing season length being a critical determinant of growth rate, and high carbon isotope discrimination values reflecting optimal hydration conditions. Correlation plots of 13C and 18O values show that species (Chorisodontium aciphyllum / Polytrichum strictum) and growth form (hummock / bank) are the major determinants of measured isotope ratios. The interplay between moss growth form, photosynthetic physiology, water status and isotope composition are compared with developments of secondary proxies, such as chlorophyll fluorescence. These approaches provide a framework to consider the potential impact of climate change on terrestrial Antarctic habitats as well as having implications for future studies of temperate, boreal and Arctic peatlands. There are many urgent ecological and environmental problems in the Arctic related to mosses in a changing climate, but the geographical ranges of species and life-forms are difficult to track individually. Our goal was to translate what we have learned from the more simple systems in Antarctica, for application to Arctic habitats. © 2014 John Wiley & Sons Ltd.

  17. Geologic history of the polar regions of Mars based on Mars Global survey data. I. Noachian and Hesperian Periods

    Science.gov (United States)

    Tanaka, K.L.; Kolb, E.J.

    2001-01-01

    During the Noachian Period, the south polar region of Mars underwent intense cratering, construction of three groups of volcanoes, widespread contractional deformation, resurfacing of low areas, and local dissection of valley networks; no evidence for polar deposits, ice sheets, or glaciation is recognized. South polar Hesperian geology is broadly characterized by waning impacts, volcanism, and tectonism. Emplacement of the polar Dorsa Argentea Formation (DAF) occurred during the Hesperian Period. Mars Orbiter Laser Altimeter topographic data and Mars Orbiter Camera images elucidate stratigraphic, morphologic, and topographic relations, permitting the dividing of the DAF into eight members, which surround and underlie about half of the Amazonian south polar layered deposits. The lobate fronts and lack of typical volcanic-flow morphology of the six plains units indicate that they may be made up of debris flows. We think that these flows, tens of meters to 200 m thick, may have originated by the discharge of huge volumes of slurry fluidized by ground water or liquid CO2, perhaps triggered by local impacts, igneous activity, or basal melting beneath polar deposits. The cavi and rugged members include irregular depressions that penetrate the subsurface; some of the pits have raised rims. The depressions may have formed by collapse due to expulsion of subsurface material in which local explosive activity built up the raised rims. Further, smaller eruptions of volatile-rich material may have resulted in narrow, sinuous channel deposits within aggrading fine-grained unconsolidated material perhaps produced by gaseous discharge of subsurface volatiles; preferential erosion of the latter material could have produced the Dorsa Argentea-type ginuous ridges associated mainly with the DAF. Alternatively, the ridges may be eskers, but the lack of associated glacial and fluvial morphologies casts doubt on this interpretation. The knobby, degraded materials forming Scandia Colles

  18. Photoelectron reflection and scattering at Venus: an upper limit on the "polar wind" ambipolar electric field, and a new source of top-side ionospheric heating

    Science.gov (United States)

    Collinson, Glyn; Glocer, Alex; Grebowsky, Joe; Peterson, William; Frahm, Rudy; Moore, Thomas; Gilbert, Lin; Coates, Andrew

    2015-04-01

    An important mechanism in the generation of Earth's polar wind is the ambipolar potential generated by the outflow along open field lines of superthermal electrons. This ≈20V electric potential assists ions in overcoming the gravitational potential, and is a key mechanism for Terrestrial ionospheric escape. At Venus, except in rare circumstances, every field line is open, and a similar outflow of ionospheric electrons is observed. It is thus hypothesized that a similar electric potential may be present at Venus, contributing to global ionospheric loss. However, a very sensitive electric field instrument would be required to directly measure this potential, and no such instrument has yet been flown to Venus. In this pilot study, we examine photoelectron spectra measured by the ASPERA-ELS instrument on the Venus Express to put an initial upper bound on the total potential drop above 350km of Φ current understanding, a "polar wind" like ambipolar electric field may not be as important a mechanism for atmospheric escape as previously suspected. Additionally, we find our spectra are consistent with the scattering of photoelectrons, the heating from which which we hypothesize may act as a source of top-side ionospheric heating, and may play a role in influencing the scale height of the ionosphere.

  19. Cervical Epidural Anaesthesia for Radical Mastectomy and Chronic Regional Pain Syndrome of Upper Limb - A Case Report

    Directory of Open Access Journals (Sweden)

    Ashok Jadon

    2009-01-01

    Full Text Available A 47-yrs-female patient presented with carcinoma right breast, swelling and allodynia of right upper limb. radical mastectomy with axillary clearance and skin grafting was done under cervical epidural anaesthesia through 18G epidural catheter placed at C6/C7 level. Postoperative analgesia and rehabilitation of affected right upper limb was managed by continuous epidural infusion of 0.125% bupivacaine and 2.5 µg/ml -1 clonidine solution through epidu-ral catheter for 5 days and physiotherapy. This case report highlights the usefulness of cervical epidural analgesia in managing a complex situation of carcinoma breast with associated periarthitis of shoulder joint and chronic regional pain syndrome (CRPS of right upper limb.

  20. Studying the Representation Accuracy of the Earth's Gravity Field in the Polar Regions Based on the Global Geopotential Models

    Science.gov (United States)

    Koneshov, V. N.; Nepoklonov, V. B.

    2018-05-01

    The development of studies on estimating the accuracy of the Earth's modern global gravity models in terms of the spherical harmonics of the geopotential in the problematic regions of the world is discussed. The comparative analysis of the results of reconstructing quasi-geoid heights and gravity anomalies from the different models is carried out for two polar regions selected within a radius of 1000 km from the North and South poles. The analysis covers nine recently developed models, including six high-resolution models and three lower order models, including the Russian GAOP2012 model. It is shown that the modern models determine the quasi-geoid heights and gravity anomalies in the polar regions with errors of 5 to 10 to a few dozen cm and from 3 to 5 to a few dozen mGal, respectively, depending on the resolution. The accuracy of the models in the Arctic is several times higher than in the Antarctic. This is associated with the peculiarities of gravity anomalies in every particular region and with the fact that the polar part of the Antarctic has been comparatively less explored by the gravity methods than the polar Arctic.

  1. Atmospheric Modeling of the Martian Polar Regions: One Mars Year of CRISM EPF Observations of the South Pole

    Science.gov (United States)

    Brown, A. J.; Wolff, M. J.

    2009-03-01

    We have used CRISM Emission Phase Function gimballed observations to investigate atmospheric dust/ice opacity and surface albedo in the south polar region for the first Mars year of MRO operations. This covers the MY28 "dust event" and cap recession.

  2. Average Potential Temperature of the Upper Mantle and Excess Temperatures Beneath Regions of Active Upwelling

    Science.gov (United States)

    Putirka, K. D.

    2006-05-01

    The question as to whether any particular oceanic island is the result of a thermal mantle plume, is a question of whether volcanism is the result of passive upwelling, as at mid-ocean ridges, or active upwelling, driven by thermally buoyant material. When upwelling is passive, mantle temperatures reflect average or ambient upper mantle values. In contrast, sites of thermally driven active upwellings will have elevated (or excess) mantle temperatures, driven by some source of excess heat. Skeptics of the plume hypothesis suggest that the maximum temperatures at ocean islands are similar to maximum temperatures at mid-ocean ridges (Anderson, 2000; Green et al., 2001). Olivine-liquid thermometry, when applied to Hawaii, Iceland, and global MORB, belie this hypothesis. Olivine-liquid equilibria provide the most accurate means of estimating mantle temperatures, which are highly sensitive to the forsterite (Fo) contents of olivines, and the FeO content of coexisting liquids. Their application shows that mantle temperatures in the MORB source region are less than temperatures at both Hawaii and Iceland. The Siqueiros Transform may provide the most precise estimate of TpMORB because high MgO glass compositions there have been affected only by olivine fractionation, so primitive FeOliq is known; olivine thermometry yields TpSiqueiros = 1430 ±59°C. A global database of 22,000 MORB show that most MORB have slightly higher FeOliq than at Siqueiros, which translates to higher calculated mantle potential temperatures. If the values for Fomax (= 91.5) and KD (Fe-Mg)ol-liq (= 0.29) at Siqueiros apply globally, then upper mantle Tp is closer to 1485 ± 59°C. Averaging this global estimate with that recovered at Siqueiros yields TpMORB = 1458 ± 78°C, which is used to calculate plume excess temperatures, Te. The estimate for TpMORB defines the convective mantle geotherm, and is consistent with estimates from sea floor bathymetry and heat flow (Stein and Stein, 1992), and

  3. 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.

  4. GeoMapApp as a platform for visualizing marine data from Polar Regions

    Science.gov (United States)

    Nitsche, F. O.; Ryan, W. B.; Carbotte, S. M.; Ferrini, V.; Goodwillie, A. M.; O'hara, S. H.; Weissel, R.; McLain, K.; Chinhong, C.; Arko, R. A.; Chan, S.; Morton, J. J.; Pomeroy, D.

    2012-12-01

    To maximize the investment in expensive fieldwork the resulting data should be re-used as much as possible. In addition, unnecessary duplication of data collection effort should be avoided. This becomes even more important if access to field areas is as difficult and expensive as it is in Polar Regions. Making existing data discoverable in an easy to use platform is key to improve re-use and avoid duplication. A common obstacle is that use of existing data is often limited to specialists who know of the data existence and also have the right tools to view and analyze these data. GeoMapApp is a free, interactive, map based tool that allows users to discover, visualize, and analyze a large number of data sets. In addition to a global view, it provides polar map projections for displaying data in Arctic and Antarctic areas. Data that have currently been added to the system include Arctic swath bathymetry data collected from the USCG icebreaker Healy. These data are collected almost continuously including from cruises where bathymetry is not the main objective and for which existence of the acquired data may not be well known. In contrast, existence of seismic data from the Antarctic continental margin is well known in the seismic community. They are archived at and can be accessed through the Antarctic Seismic Data Library System (SDLS). Incorporating these data into GeoMapApp makes an even broader community aware of these data and the custom interface, which includes capabilities to visualize and explore these data, allows users without specific software or knowledge of the underlying data format to access the data. In addition to investigating these datasets, GeoMapApp provides links to the actual data sources to allow specialists the opportunity to re-use the original data. Important identification of data sources and data references are achieved on different levels. For access to the actual Antarctic seismic data GeoMapApp links to the SDLS site, where users have

  5. TADPOL: A 1.3 mm Survey of Dust Polarization in Star-forming Cores and Regions

    OpenAIRE

    Hull, Charles L. H.; Plambeck, Richard L.; Kwon, Woojin; Bower, Geoffrey C.; Carpenter, John M.; Crutcher, Richard M.; Fiege, Jason D.; Franzmann, Erica; Hakobian, Nicholas S.; Heiles, Carl; Houde, Martin; Hughes, A. Meredith; Lamb, James W.; Looney, Leslie W.; Marrone, Daniel P.

    2014-01-01

    We present λ 1.3 mm Combined Array for Research in Millimeter-wave Astronomy observations of dust polarization toward 30 star-forming cores and eight star-forming regions from the TADPOL survey. We show maps of all sources, and compare the ~2".5 resolution TADPOL maps with ~20" resolution polarization maps from single-dish submillimeter telescopes. Here we do not attempt to interpret the detailed B-field morphology of each object. Rather, we use average B-field orientations to derive conclusi...

  6. Observation of electron biteout regions below sporadic E layers at polar latitudes

    Directory of Open Access Journals (Sweden)

    G. A. Lehmacher

    2015-03-01

    Full Text Available The descent of a narrow sporadic E layer near 95 km altitude over Poker Flat Research Range in Alaska was observed with electron probes on two consecutive sounding rockets and with incoherent scatter radar during a 2 h period near magnetic midnight. A series of four trimethyl aluminum chemical releases demonstrated that the Es layer remained just slightly above the zonal wind node, which was slowly descending due to propagating long-period gravity waves. The location of the layer is consistent with the equilibrium position due to combined action of the wind shear and electric fields. Although the horizontal electric field could not be measured directly, we estimate that it was ~ 2 mV m−1 southward, consistent with modeling the vertical ion drift, and compatible with extremely quiet conditions. Both electron probes observed deep biteout regions just below the Es enhancements, which also descended with the sporadic layers. We discuss several possibilities for the cause of these depletions; one possibility is the presence of negatively charged, nanometer-sized mesospheric smoke particles. Such particles have recently been detected in the upper mesosphere, but not yet in immediate connection with sporadic E. Our observations of electron depletions suggest a new process associated with sporadic E.

  7. Geologic map of the upper Arkansas River valley region, north-central Colorado

    Science.gov (United States)

    Kellogg, Karl S.; Shroba, Ralph R.; Ruleman, Chester A.; Bohannon, Robert G.; McIntosh, William C.; Premo, Wayne R.; Cosca, Michael A.; Moscati, Richard J.; Brandt, Theodore R.

    2017-11-17

    This 1:50,000-scale U.S. Geological Survey geologic map represents a compilation of the most recent geologic studies of the upper Arkansas River valley between Leadville and Salida, Colorado. The valley is structurally controlled by an extensional fault system that forms part of the prominent northern Rio Grande rift, an intra-continental region of crustal extension. This report also incorporates new detailed geologic mapping of previously poorly understood areas within the map area and reinterprets previously studied areas. The mapped region extends into the Proterozoic metamorphic and intrusive rocks in the Sawatch Range west of the valley and the Mosquito Range to the east. Paleozoic rocks are preserved along the crest of the Mosquito Range, but most of them have been eroded from the Sawatch Range. Numerous new isotopic ages better constrain the timing of both Proterozoic intrusive events, Late Cretaceous to early Tertiary intrusive events, and Eocene and Miocene volcanic episodes, including widespread ignimbrite eruptions. The uranium-lead ages document extensive about 1,440-million years (Ma) granitic plutonism mostly north of Buena Vista that produced batholiths that intruded an older suite of about 1,760-Ma metamorphic rocks and about 1,700-Ma plutonic rocks. As a result of extension during the Neogene and possibly latest Paleogene, the graben underlying the valley is filled with thick basin-fill deposits (Dry Union Formation and older sediments), which occupy two sub-basins separated by a bedrock high near the town of Granite. The Dry Union Formation has undergone deep erosion since the late Miocene or early Pliocene. During the Pleistocene, ongoing steam incision by the Arkansas River and its major tributaries has been interrupted by periodic aggradation. From Leadville south to Salida as many as seven mapped alluvial depositional units, which range in age from early to late Pleistocene, record periodic aggradational events along these streams that are

  8. The Rock Art of Upper Tibet and Ladakh: Inner Asian cultural adaptation, regional differentiation and the Western Tibetan Plateau Style

    OpenAIRE

    Bruneau , Laurianne; Bellezza , John V.

    2013-01-01

    International audience; This paper examines common thematic and esthetic features discernable in the rock art of the western portion of the Tibetan plateau. This rock art is international in scope; it includes Ladakh (La-dwags) (under Indian jurisdiction), Tö (Stod) and the Changthang (Byang-thang) (under Chinese administration) hereinafter called Upper Tibet. This work sets out the relationship of this art to other regions of Inner Asia and defines what we call the 'Western Tibetan Plateau S...

  9. A New Lunar Topographic Map of the Moon by KAGUYA-LALT: The First Precise Topography of the Polar Regions

    Science.gov (United States)

    Araki, H.; Ishihara, Y.; Noda, H.; Goossens, S.; Tazawa, S.; Kawano, N.; Sasaki, S.; Oberst, J.

    2008-12-01

    The Japanese lunar explorer KAGUYA (SELENE) was launched successfully on September 14th, 2007. A laser altimeter (LALT) is on board the main orbiter of KAGUYA. The objectives of LALT are (1) determination of lunar global figure, (2) studies in internal structure and surface processes, (3) exploration of the lunar pole regions, and (4) reduction of lunar occultation data. LALT transmits laser pulses whose time width is about 20 nano-seconds and pulse interval is 1 second. Range accuracy is up to 5m. The range data are transformed to the topography of the moon with the aid of position and attitude data of the main orbiter. From the end of December 2007, LALT started continuous operation and a global topography map with unprecedented resolution was produced. Lunar mean radius is estimated as 1737.15±0.01 km and the COM-COF offset is 1.94 km based on the spherical harmonic model STM359_grid-02 derived from LALT topography. The amplitude of the power spectrum of STM359_grid-02 is larger than that of the previous model at L>30 degrees, which may reflect the process of basin formation and/or crustal evolution. In the polar regions where previous CLEMENTINE altimeter did not cover, many topographic features that were difficult to see on the imagery from spacecraft or ground based radar are discovered. The sunlit rate in the lunar polar regions is estimated by using the polar topographic map made from LALT topography. We found that i) the highest sunlit rate is 93~96 % in both polar regions and ii) the eternal shadow area is smaller than previous estimations. These results will be of great use for the planning of the lunar polar exploration in near future.

  10. First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)

    Energy Technology Data Exchange (ETDEWEB)

    Biselli, Angela; Burkert, Volker; Amaryan, Moscov; Amaryan, Moskov; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bedlinskiy, Ivan; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Blaszczyk, Lukasz; Bookwalter, Craig; Boyarinov, Sergey; Bosted, Peter; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crede, Volker; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Deur, Alexandre; Dhamija, Seema; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dzyubak, Oleksandr; Egiyan, Hovanes; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feuerbach, Robert; Fersch, Robert; Forest, Tony; Fradi, Ahmed; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hassall, Neil; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Kossov, Mikhail; Krahn, Zebulun; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Mirazita, Marco; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kil; Park, Seungkyung; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Weygand, Dennis; Williams, M.; Wolin, Elliott; Wood, Michael; Yegneswaran, Amrit; Yurov, Mikhail; Zana, Lorenzo; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen

    2008-10-01

    DOI: http://dx.doi.org/10.1103/PhysRevC.78.045204
    The exclusive channel polarized proton(polarized e,e prime p)pi0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the pi0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A_{1/2} and S_{1/2} for the Roper resonance N(1400)P11, and the N(1535)S11 and N(1520)D13 states.

  11. Regional patterns of major nonnative invasive plants and associated factors in upper Midwest forests

    Science.gov (United States)

    Zhaofei Fan; W. Keith Moser; Mark H. Hansen; Mark D. Nelson

    2013-01-01

    Nonnative invasive plants (IPs) are rapidly spreading into natural ecosystems (e.g., forests and grasslands). Potential threats of IP invasion into natural ecosystems include biodiversity loss, structural and environmental change, habitat degradation, and economic losses. The Upper Midwest of the United States encompasses the states of Illinois, Indiana, Iowa, Michigan...

  12. Centennial- to decadal-scale monsoon precipitation variations in the upper Hanjiang River region, China over the past 6650 years

    Science.gov (United States)

    Tan, Liangcheng; Cai, Yanjun; Cheng, Hai; Edwards, Lawrence R.; Gao, Yongli; Xu, Hai; Zhang, Haiwei; An, Zhisheng

    2018-01-01

    The upper Hanjiang River region is the recharge area of the middle route of South-to-North Water Transfer Project. The region is under construction of the Hanjiang-Weihe River Water Transfer Project in China. Monsoon precipitation variations in this region are critical to water resource and security of China. In this study, high-resolution monsoon precipitation variations were reconstructed in the upper Hanjiang River region over the past 6650 years from δ18O and δ13C records of four stalagmites in Xianglong cave. The long term increasing trend of stalagmite δ18O record since the middle Holocene is consistent with other speleothem records from monsoonal China. This trend follows the gradually decreasing Northern Hemisphere summer insolation, which indicates that solar insolation may control the orbital-scale East Asian summer monsoon (EASM) variations. Despite the declined EASM intensity since the middle Holocene, local precipitation may not have decreased remarkably, as revealed by the δ13C records. A series of centennial- to decadal-scale cyclicity was observed, with quasi-millennium-, quasi-century-, 57-, 36- and 22-year cycles by removing the long-term trend of stalagmite δ18O record. Increased monsoon precipitation during periods of 4390-3800 a BP, 3590-2960 a BP, 2050-1670 a BP and 1110-790 a BP had caused four super-floods in the upper reach of Hanjiang River. Dramatically dry climate existed in this region during the 5.0 ka and 2.8 ka events, coinciding with notable droughts in other regions of monsoonal China. Remarkably intensified and southward Westerly jet, together with weakened summer monsoon, may delay the onset of rainy seasons, resulting in synchronous decreasing of monsoon precipitation in China during the two events. During the 4.2 ka event and the Little Ice Age, the upper Hanjiang River region was wet, which was similar to the climate conditions in central and southern China, but was the opposite of drought observed in northern China. We

  13. Satellite and ground measurements of latitude distribution of upper ionosphere parameters in the region of the main trough of ionization

    International Nuclear Information System (INIS)

    Filippov, V.M.; Alekseev, V.N.; Afonin, V.V.

    1988-01-01

    Results of simultaneous complex measurements of subauroral ionosphere structure at observations of charged-particle precipitation at Interkosmos-19 satellite, electron concentration and temperature at Kosmos-900 satellite, ionosphere parameters and plasma convection at Zhigansk (L∼4) and Jakutsk (L∼3) stations and 630.0 mm line luminescence by scanning photometer at Zhigansk station, carried out on the 26 - 27.03.1979, are presented. It is found, that the through polar edge is formed by low-energy electron precipitations in diffuse auroral zone. It is confirmed by spatial coincidence of diffuse precipitations equatorial boundary, determined by satellite and ground optical measurements, with the ionization main through polar edge, determined by ground ionospherical observation and satellite measurements Ne at Kosmos-900 satellite. Results of these complex experiments show as well, that one of the main mechanisms of main ionospherical through formation may be plasma convection peculiarities within F region at subauroral zone widthes

  14. Reflectance of Mercury's Polar Regions: Calibration and Implications for Mercury's Volatiles

    Science.gov (United States)

    Neumann, G. A.; Sun, X.; Cao, A.; Deutsch, A. N.; Head, J. W.

    2018-05-01

    Calibration of laser altimeter reflectances under widely varying conditions is supported by laboratory data from an engineering simulator to address the distribution of volatile deposits in Mercury's polar cold traps.

  15. Newborn hearing screening: analysis and outcomes after 100,000 births in Upper-Normandy French region.

    Science.gov (United States)

    Caluraud, Sophie; Marcolla-Bouchetemblé, Aurore; de Barros, Angélique; Moreau-Lenoir, Florence; de Sevin, Emmanuel; Rerolle, Stéphane; Charrière, Elisabeth; Lecler-Scarcella, Véronique; Billet, François; Obstoy, Marie-Françoise; Amstutz-Montadert, Isabelle; Marie, Jean-Paul; Lerosey, Yannick

    2015-06-01

    Neonatal hearing impairment is a common disorder with a prevalence of 1 to 2‰ worldwide, with significant consequences on overall development when rehabilitated too late. New-born hearing screening has been implemented in the 1990s in most European countries and the USA. The Upper-Normandy region of France has been conducting a pilot program since 1999. The aim of this prospective study was to evaluate and critically analyse it. The Upper-Normandy universal new-born hearing screening program is performed in two steps. Between 1999 and 2004, first, we administered a Transient Evoked Oto Acoustic Emission (TEOAE) test was administered a few days after birth for healthy newborns without risk factors. For newborns admitted to a neonatal intensive care unit (NICU) or presenting risk factors, was administered an automated auditory brainstem response (AABR) test prior to discharge. Second, newborns who failed the initial hearing screening were retested as outpatients using TEOAE. Since 2004, infants who failed the initial screen were tested with AABR 3 to 4 weeks later as outpatients, providing an opportunity to compare the two protocols. Overall screening coverage in the Upper-Normandy region is 99.8%. First step coverage is 99.58% in well-infant nurseries and 97.09% in the NICU. The test-retest procedure during the first step and the use of AABR for the second resulted in higher follow-up rates and lower false positive rates. The Upper-Normandy region universal newborn hearing screening program facilitated diagnosis and rehabilitation of infants before age of 9 months, most notably when severe to profound hearing impairment was found. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Uranium minerals in Upper Carboniferous rocks in the Nowa Ruda region

    International Nuclear Information System (INIS)

    Bareja, E.

    1981-01-01

    Results of mineralogical studies on uranium in Upper Carboniferous rocks (Glinik Beds - Westphalian C - D and Ludwikowice Beds - Stephanian) in the vicinities of Nowa Ruda (Central Sudetic Depression) are presented. Uranium mineralization is here related to sandstones and polymictic conglomerates with clay and clay-carbonate cement. The major uranium-bearing horizon was found in middle part of the Glinik Beds, and some increase in uranium content - at the base of that unit. In the case of Stephanian rocks, points with uranium mineralization were found in various parts of the Ludwikowice Beds sequence: in basal conglomerate horizon and platy sandstones. Uranium minerals mainly occur in cement of sandstones and conglomerates. They were mainly identified as uranium blende and minerals of the sulfate group - zippeite and uranopilite. Mineralized uranium-bearing horizons display mineral paragenesis typical of Upper Carboniferous rocks of the Central Sudetic Depression: uranium blende, pyrite, chalcopyrite, sphalerite and galena. (author)

  17. UPPER JURASSIC OUTCROPS ALONG THE CALDAS DA RAINHA DIAPIR, WEST CENTRAL PORTUGAL: A REGIONAL GEOHERITAGE OVERVIEW

    OpenAIRE

    DINIS, JORGE; BERNARDES, CRISTINA

    2004-01-01

    The Mesozoic Portuguese geological heritage is very rich and varied, a legacy of the position in the western margin of Iberia and its relationship with the evolution of the North Atlantic, with an interesting tectonic history since the Late Triassic. Regarding the Upper Jurassic several connections can be established between the tectonics and the stratigraphic record in the area surrounding the Caldas da Rainha structure: the basement and salt pillow control on deposition; the beginning of a ...

  18. In Situ Atmospheric Pressure Measurements in the Martian Southern Polar Region: Mars Volatiles and Climate Surveyor Meteorology Package on the Mars Polar Lander

    Science.gov (United States)

    Harri, A.-M.; Polkko, J.; Siili, T.; Crisp, D.

    1998-01-01

    Pressure observations are crucial for the success of the Mars Volatiles and Climate Surveyor (MVACS) Meteorology (MET) package onboard the Mars Polar Lander (MPL), due for launch early next year. The spacecraft is expected to land in December 1999 (L(sub s) = 256 degrees) at a high southern latitude (74 degrees - 78 degrees S). The nominal period of operation is 90 sols but may last up to 210 sols. The MVACS/MET experiment will provide the first in situ observations of atmospheric pressure, temperature, wind, and humidity in the southern hemisphere of Mars and in the polar regions. The martian atmosphere goes through a large-scale atmospheric pressure cycle due to the annual condensation/sublimation of the atmospheric CO2. Pressure also exhibits short period variations associated with dust storms, tides, and other atmospheric events. A series of pressure measurements can hence provide us with information on the large-scale state and dynamics of the atmosphere, including the CO2 and dust cycles as well as local weather phenomena. The measurements can also shed light on the shorter time scale phenomena (e.g., passage of dust devils) and hence be important in contributing to our understanding of mixing and transport of heat, dust, and water vapor.

  19. TADPOL: A 1.3 mm SURVEY OF DUST POLARIZATION IN STAR-FORMING CORES AND REGIONS

    International Nuclear Information System (INIS)

    Hull, Charles L. H.; Plambeck, Richard L.; Bower, Geoffrey C.; Heiles, Carl; Kwon, Woojin; Carpenter, John M.; Lamb, James W.; Pillai, Thushara; Crutcher, Richard M.; Hakobian, Nicholas S.; Looney, Leslie W.; Fiege, Jason D.; Franzmann, Erica; Houde, Martin; Hughes, A. Meredith; Marrone, Daniel P.; Matthews, Brenda C.; Pound, Marc W.; Rahman, Nurur; Sandell, Göran

    2014-01-01

    We present λ 1.3 mm Combined Array for Research in Millimeter-wave Astronomy observations of dust polarization toward 30 star-forming cores and eight star-forming regions from the TADPOL survey. We show maps of all sources, and compare the ∼2.''5 resolution TADPOL maps with ∼20'' resolution polarization maps from single-dish submillimeter telescopes. Here we do not attempt to interpret the detailed B-field morphology of each object. Rather, we use average B-field orientations to derive conclusions in a statistical sense from the ensemble of sources, bearing in mind that these average orientations can be quite uncertain. We discuss three main findings. (1) A subset of the sources have consistent magnetic field (B-field) orientations between large (∼20'') and small (∼2.''5) scales. Those same sources also tend to have higher fractional polarizations than the sources with inconsistent large-to-small-scale fields. We interpret this to mean that in at least some cases B-fields play a role in regulating the infall of material all the way down to the ∼1000 AU scales of protostellar envelopes. (2) Outflows appear to be randomly aligned with B-fields; although, in sources with low polarization fractions there is a hint that outflows are preferentially perpendicular to small-scale B-fields, which suggests that in these sources the fields have been wrapped up by envelope rotation. (3) Finally, even at ∼2.''5 resolution we see the so-called polarization hole effect, where the fractional polarization drops significantly near the total intensity peak. All data are publicly available in the electronic edition of this article

  20. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    OpenAIRE

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-01-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that ...

  1. Brain region distribution and patterns of bioaccumulative perfluoroalkyl carboxylates and sulfonates in east greenland polar bears (Ursus maritimus).

    Science.gov (United States)

    Greaves, Alana K; Letcher, Robert J; Sonne, Christian; Dietz, Rune

    2013-03-01

    The present study investigated the comparative accumulation of perfluoroalkyl acids (PFAAs) in eight brain regions of polar bears (Ursus maritimus, n = 19) collected in 2006 from Scoresby Sound, East Greenland. The PFAAs studied were perfluoroalkyl carboxylates (PFCAs, C(6) -C(15) chain lengths) and sulfonates (C(4) , C(6) , C(8) , and C(10) chain lengths) as well as selected precursors including perfluorooctane sulfonamide. On a wet-weight basis, blood-brain barrier transport of PFAAs occurred for all brain regions, although inner regions of the brain closer to incoming blood flow (pons/medulla, thalamus, and hypothalamus) contained consistently higher PFAA concentrations compared to outer brain regions (cerebellum, striatum, and frontal, occipital, and temporal cortices). For pons/medulla, thalamus, and hypothalamus, the most concentrated PFAAs were perfluorooctane sulfonate (PFOS), ranging from 47 to 58 ng/g wet weight, and perfluorotridecanoic acid, ranging from 43 to 49 ng/g wet weight. However, PFOS and the longer-chain PFCAs (C(10) -C(15) ) were significantly (p  0.05) different among brain regions. The burden of the sum of PFCAs, perfluoroalkyl sulfonates, and perfluorooctane sulfonamide in the brain (average mass, 392 g) was estimated to be 46 µg. The present study demonstrates that both PFCAs and perfluoroalkyl sulfonates cross the blood-brain barrier in polar bears and that wet-weight concentrations are brain region-specific. Copyright © 2012 SETAC.

  2. The Great Solar Active Region NOAA 12192: Helicity Transport, Filament Formation, and Impact on the Polar Field

    Science.gov (United States)

    Petrie, Gordon; McMaken, Tyler C.

    2017-08-01

    The solar active region (AR), NOAA 12192, appeared in 2014 October as the largest AR in 24 years. Here we examine the counterintuitive nature of two diffusion-driven processes in the region: the role of helicity buildup in the formation of a major filament, and the relationship between the effects of supergranular diffusion and meridional flow on the AR and on the polar field. Quantitatively, calculations of current helicity and magnetic twist from Helioseismic and Magnetic Imager (HMI) vector magnetograms indicate that, though AR 12192 emerged with negative helicity, positive helicity from subsequent flux emergence, consistent with the hemispheric sign-preference of helicity, increased over time within large-scale, weak-field regions such as those near the polarity inversion line (PIL). Morphologically, Atmospheric Imaging Assembly observations of filament barbs, sigmoidal patterns, and bases of Fe xii stalks initially exhibited signatures of negative helicity, and the long filament that subsequently formed had a strong positive helicity consistent with the helicity buildup along the PIL. We find from full-disk HMI magnetograms that AR 12192's leading positive flux was initially closer to the equator but, owing either to the region’s magnetic surroundings or to its asymmetric flux density distribution, was transported poleward more quickly on average than its trailing negative flux, contrary to the canonical pattern of bipole flux transport. This behavior caused the AR to have a smaller effect on the polar fields than expected and enabled the formation of the very long neutral line where the filament formed.

  3. Acetylene C2H 2 retrievals from MIPAS data and regions of enhanced upper tropospheric concentrations in August 2003

    Directory of Open Access Journals (Sweden)

    V. P. Kanawade

    2011-10-01

    Full Text Available Acetylene (C2H2 volume mixing ratios (VMRs have been successfully retrieved from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS Level 1B radiances during August 2003, providing the first global map of such data and ratios to CO in the literature. The data presented here contain most information between 300 hPa and 100 hPa with systematic errors less than 10% at the upper levels. Random errors per point are less than 15% at lower levels and are closer to 30% at 100 hPa. Global distributions of the C2H2 and C2H2/CO ratio confirm significant features associated with both the Asian monsoon anticyclone and biomass burning for this important hydrocarbon in a characteristic summer month (August 2003, showing tight correlations regionally, particularly at lower to medium values, but globally emphasising the differences between sources and lifetimes of CO and C2H2. The correlations are seen to be particularly disturbed in the regions of highest C2H2 concentrations, indicating variability in the surface emissions or fast processing. A strong isolation of C2H2 within the Asian monsoon anticyclone is observed, evidencing convective transport into the upper troposphere, horizontal advection within the anticyclone at 200 hPa, distinct gradients at the westward edge of the vortex and formation of a secondary dynamical feature from the eastward extension of the anticyclone outflow over the Asian Pacific. Ratios of C2H2/CO are consistent with the evidence from the cross-sections that the C2H2 is uplifted rapidly in convection. Observations are presented of enhanced C2H2 associated with the injection from biomass burning into the upper troposphere and the outflow from Africa at 200 hPa into both the Atlantic and Indian Oceans. In the biomass burning regions, C2H2 and CO are well correlated, but the uplift is less marked and peaks at lower altitudes compared to the strong effects observed in the Asian monsoon anticyclone. Ratios of C2H2/CO

  4. Hydrologic Conditions that Influence Streamflow Losses in a Karst Region of the Upper Peace River, Polk County, Florida

    Science.gov (United States)

    Metz, P.A.; Lewelling, B.R.

    2009-01-01

    The upper Peace River from Bartow to Fort Meade, Florida, is described as a groundwater recharge area, reflecting a reversal from historical groundwater discharge patterns that existed prior to the 1950s. The upper Peace River channel and floodplain are characterized by extensive karst development, with numerous fractures, crevasses, and sinks that have been eroded in the near-surface and underlying carbonate bedrock. With the reversal in groundwater head gradients, river water is lost to the underlying groundwater system through these karst features. An investigation was conducted to evaluate the hydrologic conditions that influence streamflow losses in the karst region of the upper Peace River. The upper Peace River is located in a basin that has been altered substantially by phosphate mining and increases in groundwater use. These alterations have changed groundwater flow patterns and caused streamflow declines through time. Hydrologic factors that have had the greatest influence on streamflow declines in the upper Peace River include the lowering of the potentiometric surfaces of the intermediate aquifer system and Upper Floridan aquifer beneath the riverbed elevation due to below-average rainfall (droughts), increases in groundwater use, and the presence of numerous karst features in the low-water channel and floodplain that enhance the loss of streamflow. Seepage runs conducted along the upper Peace River, from Bartow to Fort Meade, indicate that the greatest streamflow losses occurred along an approximate 2-mile section of the river beginning about 1 mile south of the Peace River at Bartow gaging station. Along the low-water and floodplain channel of this 2-mile section, there are about 10 prominent karst features that influence streamflow losses. Losses from the individual karst features ranged from 0.22 to 16 cubic feet per second based on measurements made between 2002 and 2007. The largest measured flow loss for all the karst features was about 50 cubic

  5. Radio-continuum study of the supernova remnants in the large Magellanic Cloud: An SNR with a highly polarized breakout region: SNR J0455-6838

    Directory of Open Access Journals (Sweden)

    Crawford E.J.

    2008-01-01

    Full Text Available We present the results of new moderate resolution ATCA observations of SNR J0455-6838. We found that this SNR exhibits a mostly typical appearance with rather steep and curved α=-0.81±0.18 and D=43×31±1 pc. Regions of high polarization were detected, including unusually strong (~70% region corresponding to the northern breakout. Such a strong polarization in breakout regions has not been observed in any other SNR.

  6. Mineralogy and Iron Content of the Lunar Polar Regions Using the Kaguya Spectral Profiler and the Lunar Orbiter Laser Altimeter

    Science.gov (United States)

    Lemelin, M.; Lucey, P. G.; Trang, D.; Jha, K.

    2016-12-01

    The lunar polar regions are of high scientific interest, but the extreme lighting conditions have made quantitative analyses using reflectance spectra difficult; some regions are in permanent shadow, and flat surfaces are difficult to correct photometrically due to the extreme grazing incidence and low signal available. Thus, most mineral maps derived from visible and near infrared reflectance spectra have been constrained to within 50° in latitude. The mineralogy of the polar regions, or 44% of the lunar surface, is almost entirely unknown. A few studies have provided compositional analysis based on the spectral shape (where strong absorption bands were present) of lithologies dominated by one or two minerals. In this study, we take a novel approach and use strong signal and well-calibrated reflectance acquired by two different instruments, the Kaguya Spectra Profiler (SP) and the Lunar Orbiter Laser Altimeter (LOLA), in order to derive the first FeO and mineral maps of the polar regions at a spatial resolution of 1 km per pixel. We use reflectance ratios from SP and calibrated reflectance data from LOLA to derive the first polar maps of FeO, which are within 2 wt.% of the FeO measured by the Lunar Prospector Gamma-Ray spectrometer up to 85° in latitude. We then use the reflectance data from SP and Hapke radiative transfer model to compute the abundance of olivine, low-calcium pyroxene, high-calcium pyroxene and plagioclase, using FeO as a constraint. The radiative transfer model yields an error in mineral abundances of 9 wt.%. We use the mineral maps to study the composition of 27 central peaks and 5 basin rings in the polar regions, and relate their composition to their depth of origin in the lunar crust. We find that the central peaks and basin rings in Feldspathic Highlands Terrane are mostly anorthositic in composition, with modal plagioclase content ranging between 66 and 92 wt.%. The central peaks and basin rings in the South Pole-Aitken basin are noritic

  7. Assessment of multimodal freight bottlenecks and alleviation strategies for upper Midwest region.

    Science.gov (United States)

    2010-05-01

    The freight that passes through the Mississippi Valley Region is high volume and has a substantial impact on the economy of the : region. According to the BTS-sponsored Commodity Flow Survey, trucks carried almost 2.5 billion tons of freight across t...

  8. 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)

  9. Geologic framework of the regional ground-water flow system in the Upper Deschutes Basin, Oregon

    Science.gov (United States)

    Lite, Kenneth E.; Gannett, Marshall W.

    2002-12-10

    Ground water is increasingly relied upon to satisfy the needs of a growing population in the upper Deschutes Basin, Oregon. Hydrogeologic studies are being undertaken to aid in management of the ground-water resource. An understanding of the geologic factors influencing ground-water flow is basic to those investigations. The geology of the area has a direct effect on the occurrence and movement of ground water. The permeability and storage properties of rock material are influenced by the proportion, size, and degree of interconnection of open spaces the rocks contain. These properties are the result of primary geologic processes such as volcanism and sedimentation, as well as subsequent processes such as faulting, weathering, or hydrothermal alteration. The geologic landscape in the study area evolved during about 30 million years of volcanic activity related to a north-south trending volcanic arc, the current manifestation of which are today’s Cascade Range volcanoes.

  10. Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

    Science.gov (United States)

    Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

    2010-01-01

    Recent satellite lidar measurements of cloud properties spanning a period of 5 years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anticorrelation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice!free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7% and 10%, respectively, as year average sea ice extent has decreased by 5% 7%. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Because longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

  11. The Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

    Science.gov (United States)

    Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

    2010-01-01

    Recent satellite lidar measurements of cloud properties spanning a period of five years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anti-correlation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7 and 10 percent, respectively, as year average sea ice extent has decreased by 5 to 7 percent. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Since longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

  12. Impacts of using reformulated and oxygenated fuel blends on the regional air quality of the upper Rhine valley

    Directory of Open Access Journals (Sweden)

    J.-F. Vinuesa

    2006-01-01

    Full Text Available The effects of using three alternative gasoline fuel blends on regional air quality of the upper Rhine valley have been investigated. The first of the tested fuels is oxygenated by addition of ethyl-tertio-butyl ether (ETBE, the second is based on a reformulation of its composition and the third on is both oxygenated and reformulated. The upper Rhine valley is a very sensitive region for pollution episodes and several meteorological and air quality studies have already been performed. High temporal and spatial emission inventories are available allowing relevant and realistic modifications of the emission inventories. The calculation period, i.e., 11 May 1998, corresponds to a regional photochemical ozone pollution episode during which ozone concentrations exceeded several times the information threshold of the ozone directive of the European Union (180 μg m-3 as 1 hourly average. New emission inventories are set up using specific emission factors related to the alternative fuels by varying the fraction of gasoline passenger cars (from 50% to 100% using the three fuel blends. Then air quality modeling simulations are performed using these emission inventories over the upper Rhine valley. The impact of alternative fuels on regional air quality is evaluated by comparing these simulations with the one using a reference emission inventory, e.g., where no modifications of the fuel composition are included. The results are analyzed by focusing on peak levels and daily averaged concentrations. The use of the alternative fuels leads to general reductions of ozone and volatile organic compounds (VOC and increases of NOx levels. We found different behaviors related to the type of the area of concern i.e. rural or urban. The impacts on ozone are enhanced in urban areas where 15% reduction of the ozone peak and daily averaged concentrations can be reached. This behavior is similar for the NOx for which, in addition, an increase of the levels can be noted

  13. Determining the source region of auroral emissions in the prenoon oval using coordinated Polar BEAR UV-imaging and DMSP particle measurements

    Science.gov (United States)

    Newell, Patrick T.; Meng, CHING-I.; Huffman, Robert E.

    1992-01-01

    The Polar Beacon Experiment and Auroral Research (Polar BEAR) satellite included the capability for imaging the dayside auroral oval in full sunlight at several wavelengths. Particle observations from the DMSP F7 satellite during dayside auroral oval crossings are compared with approximately simultaneous Polar BEAR 1356-A images to determine the magnetospheric source region of the dayside auroral oval. The source region is determined from the DMSP particle data, according to recent work concerning the classification and identification of precipitation source regions. The close DMSP/Polar BEAR coincidences all occur when the former satellite is located between 0945 and 1000 MLT. Instances of auroral arcs mapping to each of several different regions, including the boundary plasma sheet, the low-latitude boundary layer, and the plasma mantle were found. It was determined that about half the time the most prominent auroral arcs are located at the interfaces between distinct plasma regions, at least at the local time studied here.

  14. NACP MCI: CO2 Emissions Inventory, Upper Midwest Region, USA., 2007

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides a bottom-up CO2 emissions inventory for the mid-continent region of the United States for the year 2007. The study was undertaken as...

  15. NACP MCI: CO2 Emissions Inventory, Upper Midwest Region, USA., 2007

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides a bottom-up CO2 emissions inventory for the mid-continent region of the United States for the year 2007. The study was undertaken as part of...

  16. A one stop website for sharing sea ice, ocean and ice sheet data over the polar regions

    Science.gov (United States)

    Chen, Z.; Cheng, X.; Liu, J.; Hui, F.; Ding, Y.

    2017-12-01

    The polar regions, including the Arctic and Antarctic, are changing rapidly. Our capabilities to remotely monitor the state of the polar regions are increasing greatly. Satellite and airborne technologies have been deployed and further improvements are underway. Meanwhile, various algorithms have been developed to retrieve important parameters to maximize the effectiveness of available remote sensing data. These technologies and algorithms promise to greatly increase our understanding of variations in sea ice, ocean and ice sheet. However, so much information is scattered out there. It is challenging to find exactly what you are looking for by just searching it through the network. Therefore, we try to establish a common platform to sharing some key parameters for the polar regions. A group of scientists from Beijing Normal University and University at Albany developed a website as a "one-stop shop" for the current state of the polar regions. The website provides real-time (or near real-time) key parameters derived from a variety of operational satellites in an understandable, accessible and credible way. Three types of parameter, which are sea ice, ocean and ice sheet respectively, are shown and available to be downloaded in the website. Several individual parameters are contained in a specific type of parameter. The parameters of sea ice include sea ice concentration, sea ice thickness, melt pond, sea ice leads and sea ice drift. The ocean parameters contain sea surface temperature and sea surface wind. Ice sheet balance, ice velocity and some other parameters are classified into the type of ice sheet parameter. Some parameters are well-calibrated and available to be obtained from other websites, such as sea ice concentration, sea ice thickness sea surface temperature. Since these parameters are retrieved from different sensors, such as SSMI, AMSR2 etc., data format, spatial resolution of the parameters are not unified. We collected and reprocessed these

  17. Vestas Pinaria Region: Original Basaltic Achondrite Material Derived from Mixing Upper and Lower Crust

    Science.gov (United States)

    Mcfadden, L. A.; Combe, Jean-Philippe; Ammannito, Eleonora; Frigeri, Alessandro; Stephan, Katrin; Longobardo, Andrea; Palomba, Ernesto; Tosi, Federico; Zambon, Francesca; Krohn, Katrin; hide

    2015-01-01

    Analysis of data from the Dawn mission shows that the Pinaria region of Vesta spanning a portion of the rim of the Rheasilvia basin is bright and anhydrous. Reflectance spectra, absorption band centers, and their variations, cover the range of pyroxenes from diogenite-rich to howardite and eucrite compositions, with no evidence of olivine in this region. By examining band centers and depths of the floor, walls and rims of six major craters in the region, we find a lane of diogenite-rich material next to howardite-eucrite material that does not follow the local topography. The source of this material is not clear and is probably ejecta from post-Rheasilvia impacts. Material of a howardite-eucrite composition originating from beyond the Rheasilvia basin is evident on the western edge of the region. Overall, the Pinaria region exposes the complete range of basaltic achondrite parent body material, with little evidence of contamination of non-basaltic achondrite material. With both high reflectance and low abundance of hydrated material, this region of Vesta may be considered the "Pinaria desert".

  18. Polarization-resolved degenerate four-wave mixing of CdS nanocrystals in a nonresonant region

    International Nuclear Information System (INIS)

    Ma, S.M.; Seo, J.T.; Yang, Q.; Creemore, L.; Battle, R.; Tabibi, B.; Yu, W.

    2006-01-01

    The third-order susceptibilities of various concentrations of TOPO-passivated CdS nanocrystals (NCs) with the size near the Bohr radius were investigated using polarization-resolved degenerate four-wave mixing (DFWM) in a nonresonant excitation region with 532 nm wavelength and 8 ns pulse width. The second hyperpolarizabilities left angle γ h xxxx right angle and left angle γ h xyyx right angle of the CdS NCs were ∝1.25 x 10 -42 m 5 /V 2 and ∝3.66 x 10 -43 m 5 /V 2 , respectively. The ratio (left angle γ h xyyx right angle / left angle γ h xxxx right angle) of the hyperpolarizabilities was ∝0.29 that indicated a large contribution of electronic polarization process to the third-order nonlinearity of CdS NCs. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Solving the Upper Valley's housing needs: how a coalition of public and private organizations joined forces to develop housing in a region with inadequate stock and prohibitive prices

    OpenAIRE

    Dan French

    2004-01-01

    Like many communities, New Hampshire and Vermont's Upper Valley region is facing a serious housing shortage. Dan French reveals how an innovative housing coalition is working to find solutions that provide housing and protect the area's quality of life.

  20. First ever in situ observations of Venus' polar upper atmosphere density using the tracking data of the Venus Express Atmospheric Drag Experiment (VExADE)

    Science.gov (United States)

    Rosenblatt, P.; Bruinsma, S. L.; Müller-Wodarg, I. C. F.; Häusler, B.; Svedhem, H.; Marty, J. C.

    2012-02-01

    On its highly elliptical 24 h orbit around Venus, the Venus Express (VEX) spacecraft briefly reaches a periapsis altitude of nominally 250 km. Recently, however, dedicated and intense radio tracking campaigns have taken place in August 2008, October 2009, February and April 2010, for which the periapsis altitude was lowered to the 186-176 km altitude range in order to be able to probe the upper atmosphere of Venus above the North Pole for the first time ever in situ. As the spacecraft experiences atmospheric drag, its trajectory is measurably perturbed during the periapsis pass, allowing us to infer total atmospheric mass density at the periapsis altitude. A Precise Orbit Determination (POD) of the VEX motion is performed through an iterative least-squares fitting process to the Doppler tracking data, acquired by the VEX radioscience experiment (VeRa). The drag acceleration is modelled using an initial atmospheric density model (VTS3 model, Hedin, A.E., Niemann, H.B., Kasprzak, W.T., Seiff, A. [1983]. J. Geophys. Res. 88, 73-83). A scale factor of the drag acceleration is estimated for each periapsis pass, which scales Hedin's density model in order to best fit the radio tracking data. Reliable density scale factors have been obtained for 10 passes mainly from the second (October 2009) and third (April 2010) VExADE campaigns, which indicate a lower density by a factor of about 1.8 than Hedin's model predicts. These first ever in situ polar density measurements at solar minimum have allowed us to construct a diffusive equilibrium density model for Venus' thermosphere, constrained in the lower thermosphere primarily by SPICAV-SOIR measurements and above 175 km by the VExADE drag measurements (Müller-Wodarg et al., in preparation). The preliminary results of the VExADE campaigns show that it is possible to obtain with the POD technique reliable estimates of Venus' upper atmosphere densities at an altitude of around 175 km. Future VExADE campaigns will benefit from

  1. Constraining the Depth of Polar Ice Deposits and Evolution of Cold Traps on Mercury with Small Craters in Permanently Shadowed Regions

    Science.gov (United States)

    Deutsch, Ariel N.; Head, James W.; Neumann, Gregory A.; Chabot, Nancy L.

    2017-01-01

    Earth-based radar observations revealed highly reflective deposits at the poles of Mercury [e.g., 1], which collocate with permanently shadowed regions (PSRs) detected from both imagery and altimetry by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft [e.g., 2]. MESSENGER also measured higher hydrogen concentrations at the north polar region, consistent with models for these deposits to be composed primarily of water ice [3]. Enigmatic to the characterization of ice deposits on Mercury is the thickness of these radar-bright features. A current minimum bound of several meters exists from the radar measurements, which show no drop in the radar cross section between 13- and 70-cm wavelength observations [4, 5]. A maximum thickness of 300 m is based on the lack of any statistically significant difference between the height of craters that host radar-bright deposits and those that do not [6]. More recently, this upper limit on the depth of a typical ice deposit has been lowered to approximately 150 m, in a study that found a mean excess thickness of 50 +/- 35 m of radar-bright deposits for 6 craters [7]. Refining such a constraint permits the derivation of a volumetric estimate of the total polar ice on Mercury, thus providing insight into possible sources of water ice on the planet. Here, we take a different approach to constrain the thickness of water-ice deposits. Permanently shadowed surfaces have been resolved in images acquired with the broadband filter on MESSENGER's wide-angle camera (WAC) using low levels of light scattered by crater walls and other topography [8]. These surfaces are not featureless and often host small craters (less than a few km in diameter). Here we utilize the presence of these small simple craters to constrain the thickness of the radar-bright ice deposits on Mercury. Specifically, we compare estimated depths made from depth-to-diameter ratios and depths from individual Mercury Laser Altimeter (MLA

  2. Does regional anesthesia influence early outcome of upper arm arteriovenous fistula?

    International Nuclear Information System (INIS)

    Mohamed A Elsharawy; Roshdi Al-metwalli

    2010-01-01

    To assess the effect of regional anesthesia on the outcome of elbow arteriovenous fistula (AVF), prospectively studied consecutive patients with end-stage renal disease referred for permanent vascular access to the Vascular Unit of King Fahd University Hospital between September 2004 and September 2007. The patients were divided into 2 groups: Group 1: patients who underwent the construction of the AVF under regional anesthesia and Group 2: patients who were operated under general anesthesia, indicated by their preferences or failure of regional anesthesia. Data including patient characteristics and type of AVF were recorded. The internal diameter of the vein and the artery and intra-operative blood flow were measured. The complications of both types of anesthesia were recorded. The patients were followed up for three months. Eighty four cases were recruited in this study. Complete brachial plexus block was achieved in 57 (68%) patients. Seven patients were converted to general anesthesia and 20 patients had AVF under general anesthesia from the start. There were no significant differences between the 2 groups with regard to basic characteristics or operative data. There were no instances of systemic toxicity, hematomas, or nerve injury from the regional block. No major complications were reported from the general anesthesia. There was no significant difference between both groups regarding early failure of AVF (Group 1, 14% vs. Group2; 11%. P= 0.80). No significant advantage of regional over general anesthesia in terms of early outcome of AVF was seen in this study (Author).

  3. Palms and Palm Communities in the Upper Ucayali River Valley - a Little-Known Region in the Amazon Basin

    DEFF Research Database (Denmark)

    Balslev, Henrik; Eiserhardt, Wolf L.; Kristiansen, Thea

    2010-01-01

    The Amazon region and its palms are inseparable. Palms make up such an important part of the rain forest ecosystem that it is impossible to imagine the Amazon basin without them. Palms are visible in the canopy and often fill up the forest understory. Palms – because of their edible fruits...... – are cornerstone species for the survival of many animals, and palms contribute substantially to forest inventories in which they are often among the ten most important families. Still, the palms and palm communities of some parts of the Amazon basin remain poorly studied and little known. We travelled to a little......-explored corner of the western Amazon basin, the upper Ucayali river valley. There, we encountered 56 different palms, 18 of which had not been registered for the region previously, and 21 of them were found 150–400 km beyond their previously known limits....

  4. The formation of multiple layers of ice particles in the polar summer mesopause region

    Directory of Open Access Journals (Sweden)

    H. Li

    2016-01-01

    Full Text Available This paper presents a two-dimensional theoretical model to study the formation process of multiple layers of small ice particles in the polar summer mesosphere as measured by rockets and associated with polar mesosphere summer echoes (PMSE. The proposed mechanism primarily takes into account the transport processes induced by gravity waves through collision coupling between the neutral atmosphere and the ice particles. Numerical solutions of the model indicate that the dynamic influence of wind variation induced by gravity waves can make a significant contribution to the vertical and horizontal transport of ice particles and ultimately transform them into thin multiple layers. Additionally, the pattern of the multiple layers at least partially depends on the vertical wavelength of the gravity wave, the ice particle size and the wind velocity. The results presented in this paper will be helpful to better understand the occurrence of multiple layers of PMSE as well as its variation process.

  5. [Examination of upper abdominal region in high spatial resolution diffusion-weighted imaging using 3-Tesla MRI].

    Science.gov (United States)

    Terada, Masaki; Matsushita, Hiroki; Oosugi, Masanori; Inoue, Kazuyasu; Yaegashi, Taku; Anma, Takeshi

    2009-03-20

    The advantage of the higher signal-to-noise ratio (SNR) of 3-Tesla magnetic resonance imaging (3-Tesla) has the possibility of contributing to the improvement of high spatial resolution without causing image deterioration. In this study, we compared SNR and the apparent diffusion coefficient (ADC) value with 3-Tesla as the condition in the diffusion-weighted image (DWI) parameter of the 1.5-Tesla magnetic resonance imaging (1.5-Tesla) and we examined the high spatial resolution images in the imaging method [respiratory-triggering (RT) method and breath free (BF) method] and artifact (motion and zebra) in the upper abdominal region of DWI at 3-Tesla. We have optimized scan parameters based on phantom and in vivo study. As a result, 3-Tesla was able to obtain about 1.5 times SNR in comparison with the 1.5-Tesla, ADC value had few differences. Moreover, the RT method was effective in correcting the influence of respiratory movement in comparison with the BF method, and image improvement by the effective acquisition of SNR and reduction of the artifact were provided. Thus, DWI of upper abdominal region was a useful sequence for the high spatial resolution in 3-Tesla.

  6. ROTATIONAL VARIABILITY OF EARTH'S POLAR REGIONS: IMPLICATIONS FOR DETECTING SNOWBALL PLANETS

    International Nuclear Information System (INIS)

    Cowan, Nicolas B.; Robinson, Tyler; Agol, Eric; Meadows, Victoria S.; Shields, Aomawa L.; Livengood, Timothy A.; Deming, Drake; A'Hearn, Michael F.; Wellnitz, Dennis D.; Charbonneau, David; Lisse, Carey M.; Seager, Sara

    2011-01-01

    We have obtained the first time-resolved, disk-integrated observations of Earth's poles with the Deep Impact spacecraft as part of the EPOXI mission of opportunity. These data mimic what we will see when we point next-generation space telescopes at nearby exoplanets. We use principal component analysis (PCA) and rotational light curve inversion to characterize color inhomogeneities and map their spatial distribution from these unusual vantage points, as a complement to the equatorial views presented by Cowan et al. in 2009. We also perform the same PCA on a suite of simulated rotational multi-band light curves from NASA's Virtual Planetary Laboratory three-dimensional spectral Earth model. This numerical experiment allows us to understand what sorts of surface features PCA can robustly identify. We find that the EPOXI polar observations have similar broadband colors as the equatorial Earth, but with 20%-30% greater apparent albedo. This is because the polar observations are most sensitive to mid-latitudes, which tend to be more cloudy than the equatorial latitudes emphasized by the original EPOXI Earth observations. The cloudiness of the mid-latitudes also manifests itself in the form of increased variability at short wavelengths in the polar observations and as a dominant gray eigencolor in the south polar observation. We construct a simple reflectance model for a snowball Earth. By construction, our model has a higher Bond albedo than the modern Earth; its surface albedo is so high that Rayleigh scattering does not noticeably affect its spectrum. The rotational color variations occur at short wavelengths due to the large contrast between glacier ice and bare land in those wavebands. Thus, we find that both the broadband colors and diurnal color variations of such a planet would be easily distinguishable from the modern-day Earth, regardless of viewing angle.

  7. The Austrian social festival Keep the Ball Rolling in a peripheral region of Upper Styria

    Directory of Open Access Journals (Sweden)

    Gstach Isabell

    2014-03-01

    Full Text Available The “Steirische Eisenstraße” is a region located in the province of Styria in Austria, which has been struggling with a massive shift in population and age structure for some time. In 2012/13 the Austrian social festival Keep the Ball Rolling is taking place in this region. Over a period of 18 months, the social festival is providing opportunities to think of their own environment. Consequently, they can develop and implement ideas for good cohabitation and put these into practice. The main focus of this article is the demographic presentation of the “Steirische Eisenstraße” region, according to population, employment and age structure. The introduction of the social festival is fundamental in initiating successful change processes.

  8. The Steens Mountain ( Oregon) geomagnetic polarity transition ( USA). 3. Its regional significance.

    Science.gov (United States)

    Mankinen, E.A.; Larson, E.E.; Gromme, C.S.; Prevot, M.; Coe, R.S.

    1987-01-01

    Study of the variations of direction and intensity of the geomagnetic field as recorded by the Miocene lava flows on Steens Mountain, SE Oregon, has resulted in a detailed description of total field behavior during a reversal in polarity. In addition to information about the polarity reversal itself, the detailed paleomagnetic record includes several thousand years of geomagnetic history preceding and following the polarity transition at 15.5 Ma. To test the feasibility of using this record as a means of correlation in this part of the western US, comparisons are made of reconnaissance and previously published paleomagnetic records obtained from what has been thought to be the Steens Basalt or rocks of equivalent age. Despite the fact that many of these earlier studies were not detailed and were not intended for correlation purposes, convincing similarities among some of the records are evident. The Steens Basalt paleomagnetic record does, indeed, have potential as a correlation tool during this time of widespread basaltic volcanism. Concludes that findings indicate no post-20 Ma differential rotation between S-E Washington and S-central Oregon, in contrast to previous interpretations. -from Authors

  9. Regional aerosol deposition in human upper airways. Progress report, March 1, 1992--February 28, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Swift, D.L.

    1992-11-01

    Laboratory experimental studies were carried out to investigate the factors influencing the deposition of aerosols ranging in size from 1 nm to 10 {mu}m in the human nasal, oral, pharyngeal and laryngeal airways. These experimental studies were performed in replicate upper airway physical models and in human volunteer subjects. New replicate models of the oral passage of an infant, the oral passage of an adult at two openings and the combined nasal and oral airways of an adult were constructed during the period, adding to the existing models of adult, child and infant nasal and oral airways models. Deposition studies in the adult oral and adult nasal models were performed under simulated cyclic flow conditions with 1 nm particles to compare with previously measured constant flow studies. Similar studies with inertial particles (1--10 {mu}m diameter) were performed with the adult nasal model; in both instances, results with cyclic flow were similar to constant flow results using a simple average flow rate based on inspiratory volume and time of inspiration. Human subject studies were performed with particle sizes 5--20 nm for nasal inspiration; preliminary analysis shows good agreement with model studies at several representative flow rates. Nasal inspiratory inertial deposition of 1--4 {mu}m diameter particles was measured in several adults as a function of airway dimensions; dimensional changes of the valve area by decongestion did not produce concomitant deposition changes.

  10. Looking Through the Ice: Searching for Past and Present Habitable Zones in the Martian North Polar Region Using MOLA DEMs

    Science.gov (United States)

    Payne, M. C.; Farmer, J. D.

    2002-12-01

    Hydrothermal systems have been acknowledged as important gateways to accessing a potential subsurface biology (extant or extinct) on Mars. Groundwater circulation, sustained for up to one billion years by large plutonic bodies (as modeled by previous authors), might well be capable of tapping into a deep subsurface biosphere and subsequently carrying members of microbial communities to the surface. Hence, future robotic missions with near surface drilling capabilities may be able to unearth cryopreserved biosignatures, or perhaps extant organisms, in the midst of the hydrothermal system itself. Digital Elevation Models (DEMs) constructed from Mars Orbiter Laser Altimeter (MOLA) data have proved to be a valuable tool in the search for potential habitable zones for extant and extinct life, and the detection of possible hydrothermal systems on Mars. When formatted for use in a Geographical Information Systems (GIS) software package such as ESRI's ArcView, MOLA data can be used to compose DEMs. Those DEMs can, in turn, be used to create contour maps, to allow profiling through features of interest, and to generate hillshaded views, which provide an image-like perspective of a selected area. Furthermore, DEMs eliminate many problems associated with photographic images such as over-/underexposure, poor focus, and albedo values too high or low for optimal observations. During this study, DEMs were used in the analysis of several regions north of 70° N latitude, in the Martian north polar cap and polar cap margin. The regions were selected during a Viking image survey that concentrated on the location of surface expressions of potential magma-ice interactions, and hence past or present hydrothermal activity. Specific features sought included individual volcanoes and volcanic fields, as well as pseudocrater fields, subglacial volcanic constructs (such as tuyas and tindar ridges), fluvial channels and outwash plains (indicative of j”kulhlaup flooding events), possible

  11. Mountains Under Pressure: Evaluating Ecosystem Services and Livelihoods in the Upper Himalayan Region of Nepal

    NARCIS (Netherlands)

    Bhusal, Jagat K.; Chapagain, Prem Sagar; Regmi, Santosh; Gurung, Praju; Zulkafli, Zed; Karpouzoglou, T.D.; Pandeya, Bhopal; Buytaert, Wouter; Clark, Julian

    2016-01-01

    Natural resource-based livelihoods in mountainous regions are subject to new types of development as well as climate related pressures and vulnerabilities. On one hand, the integrity of the mountainous landscape is under pressure from the melting of glaciers, changes in water availability, rainfall

  12. Probabilistic full waveform inversion based on tectonic regionalization - development and application to the Australian upper mantle

    NARCIS (Netherlands)

    Käufl, P.; Fichtner, A.; Igel, H.

    2013-01-01

    We present a first study to investigate the feasibility of a probabilistic 3-D full waveform inversion based on spectral-element simulations of seismic wave propagation and Monte Carlo exploration of the model space. Through a tectonic regionalization we reduce the dimension of the model space to

  13. Chemical characterization by GC-MS and phytotoxic potential of non-polar and polar fractions of seeds of Dioteryx odorata (Aubl. Willd. from Venezuelan regions

    Directory of Open Access Journals (Sweden)

    Alberto de J. Oliveros-Bastidas

    2013-01-01

    Full Text Available Dipteryx odorata (Aubl. Willd. is a tall arboreal species native to Central and Northern South America. This paper describes the chemical characterization and phytotoxic potential of polar and non-polar extracts from D. odorata seeds. Structural determinations were accomplished by chemical derivatization and analyzed by GC/MS. The chemical composition of the non-polar fraction (hexane and dichloromethane presented fatty acids as major constituent. Medium polar and polar fractions (ethyl acetate and ethanol: water contained carboxylic acid and high 6,7-Dyhidroxycoumarin-β-D-glucopyranoside content, not previously reported for seeds of D. odorata. Extracts showed a significant level of phytotoxic activity, correlated to the content of coumarin derivatives, predominantly in the polar fraction.

  14. The Great Solar Active Region NOAA 12192: Helicity Transport, Filament Formation, and Impact on the Polar Field

    Energy Technology Data Exchange (ETDEWEB)

    McMaken, Tyler C. [National Solar Observatory REU Program, 3665 Discovery Drive, 3rd Floor, Boulder, CO 80303 (United States); Petrie, Gordon J. D., E-mail: tmcmaken@gmail.com, E-mail: gpetrie@noao.edu [National Solar Observatory, 3665 Discovery Drive, 3rd Floor, Boulder, CO 80303 (United States)

    2017-05-10

    The solar active region (AR), NOAA 12192, appeared in 2014 October as the largest AR in 24 years. Here we examine the counterintuitive nature of two diffusion-driven processes in the region: the role of helicity buildup in the formation of a major filament, and the relationship between the effects of supergranular diffusion and meridional flow on the AR and on the polar field. Quantitatively, calculations of current helicity and magnetic twist from Helioseismic and Magnetic Imager (HMI) vector magnetograms indicate that, though AR 12192 emerged with negative helicity, positive helicity from subsequent flux emergence, consistent with the hemispheric sign-preference of helicity, increased over time within large-scale, weak-field regions such as those near the polarity inversion line (PIL). Morphologically, Atmospheric Imaging Assembly observations of filament barbs, sigmoidal patterns, and bases of Fe xii stalks initially exhibited signatures of negative helicity, and the long filament that subsequently formed had a strong positive helicity consistent with the helicity buildup along the PIL. We find from full-disk HMI magnetograms that AR 12192's leading positive flux was initially closer to the equator but, owing either to the region’s magnetic surroundings or to its asymmetric flux density distribution, was transported poleward more quickly on average than its trailing negative flux, contrary to the canonical pattern of bipole flux transport. This behavior caused the AR to have a smaller effect on the polar fields than expected and enabled the formation of the very long neutral line where the filament formed.

  15. Production of positive pions from polarized protons by linearly polarized photons in the energy region 300--420 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Get' man, V.A.; Gorbenko, V.G.; Grushin, V.F.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Luchanin, A.A.; Rubashkin, A.L.; Sanin, V.M.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.; Shalatskii, S.V.

    1980-10-01

    A technique for measurement of the polarization observables ..sigma.., P, and T for the reaction ..gamma..p..-->..n..pi../sup +/ in a doubly polarized experiment (polarized proton target + linearly polarized photon beam) is described. Measurements of the angular distributions of these observables in the range of pion emission angles 30--150/sup 0/ are presented for four photon energies from 300 to 420 MeV. Inclusion of the new experimental data in an energy-independent multipole analysis of photoproduction from protons permits a more reliable selection of solutions to be made.

  16. Structural Heterogeneities in Southeast Tibet: Implications for Regional Flow in the Lower Crust and Upper Mantle

    Directory of Open Access Journals (Sweden)

    Zhi Wang

    2012-01-01

    Full Text Available Our seismic study together with the MT analysis reveal a “R-shape” flow existing in both the lower crust and uppermost mantle, which suggests the crustal deformation along the deep, large sutures (such as the Longmen Shan fault and the Anninghe Fault under the southeastern Tibetan Plateau is maintained by dynamic pressure from the regional flow intermingled with the hot upwelling asthenosphere. The material in the lower crust and uppermost mantle flowing outward from the center of the plateau is buttressed by the old, strong lithosphere that underlies the Sichuan basin, pushing up on the crust above and maintaining steep orogenic belt through dynamic pressure. We therefore consider that the “R-shape” regional flow played a key role in the crustal deformation along the deep suture zones of the Bangong-Nujiang, the Longmen-Shan faults, and other local heavily faulted zones beneath the southeastern Tibetan Plateau.

  17. Adjoint tomography of the crust and upper mantle structure beneath the Kanto region using broadband seismograms

    KAUST Repository

    Miyoshi, Takayuki; Obayashi, Masayuki; Peter, Daniel; Tono, Yoko; Tsuboi, Seiji

    2017-01-01

    A three-dimensional seismic wave speed model in the Kanto region of Japan was developed using adjoint tomography for application in the effective reproduction of observed waveforms. Starting with a model based on previous travel time tomographic results, we inverted the waveforms obtained at seismic broadband stations from 140 local earthquakes in the Kanto region to obtain the P- and S-wave speeds Vp and Vs. Additionally, all centroid times of the source solutions were determined before the structural inversion. The synthetic displacements were calculated using the spectral-element method (SEM) in which the Kanto region was parameterized using 16 million grid points. The model parameters Vp and Vs were updated iteratively by Newton’s method using the misfit and Hessian kernels until the misfit between the observed and synthetic waveforms was minimized. Computations of the forward and adjoint simulations were conducted on the K computer in Japan. The optimized SEM code required a total of 6720 simulations using approximately 62,000 node hours to obtain the final model after 16 iterations. The proposed model reveals several anomalous areas with extremely low-Vs values in comparison with those of the initial model. These anomalies were found to correspond to geological features, earthquake sources, and volcanic regions with good data coverage and resolution. The synthetic waveforms obtained using the newly proposed model for the selected earthquakes showed better fit than the initial model to the observed waveforms in different period ranges within 5–30 s. This result indicates that the model can accurately predict actual waveforms.

  18. Adjoint tomography of the crust and upper mantle structure beneath the Kanto region using broadband seismograms

    KAUST Repository

    Miyoshi, Takayuki

    2017-10-04

    A three-dimensional seismic wave speed model in the Kanto region of Japan was developed using adjoint tomography for application in the effective reproduction of observed waveforms. Starting with a model based on previous travel time tomographic results, we inverted the waveforms obtained at seismic broadband stations from 140 local earthquakes in the Kanto region to obtain the P- and S-wave speeds Vp and Vs. Additionally, all centroid times of the source solutions were determined before the structural inversion. The synthetic displacements were calculated using the spectral-element method (SEM) in which the Kanto region was parameterized using 16 million grid points. The model parameters Vp and Vs were updated iteratively by Newton’s method using the misfit and Hessian kernels until the misfit between the observed and synthetic waveforms was minimized. Computations of the forward and adjoint simulations were conducted on the K computer in Japan. The optimized SEM code required a total of 6720 simulations using approximately 62,000 node hours to obtain the final model after 16 iterations. The proposed model reveals several anomalous areas with extremely low-Vs values in comparison with those of the initial model. These anomalies were found to correspond to geological features, earthquake sources, and volcanic regions with good data coverage and resolution. The synthetic waveforms obtained using the newly proposed model for the selected earthquakes showed better fit than the initial model to the observed waveforms in different period ranges within 5–30 s. This result indicates that the model can accurately predict actual waveforms.

  19. Microbiological and ecological responses to global environmental changes in polar regions (MERGE): An IPY core coordinating project

    Science.gov (United States)

    Naganuma, Takeshi; Wilmotte, Annick

    2009-11-01

    An integrated program, “Microbiological and ecological responses to global environmental changes in polar regions” (MERGE), was proposed in the International Polar Year (IPY) 2007-2008 and endorsed by the IPY committee as a coordinating proposal. MERGE hosts original proposals to the IPY and facilitates their funding. MERGE selected three key questions to produce scientific achievements. Prokaryotic and eukaryotic organisms in terrestrial, lacustrine, and supraglacial habitats were targeted according to diversity and biogeography; food webs and ecosystem evolution; and linkages between biological, chemical, and physical processes in the supraglacial biome. MERGE hosted 13 original and seven additional proposals, with two full proposals. It respected the priorities and achievements of the individual proposals and aimed to unify their significant results. Ideas and projects followed a bottom-up rather than a top-down approach. We intend to inform the MERGE community of the initial results and encourage ongoing collaboration. Scientists from non-polar regions have also participated and are encouraged to remain involved in MERGE. MERGE is formed by scientists from Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Egypt, Finland, France, Germany, Italy, Japan, Korea, Malaysia, New Zealand, Philippines, Poland, Russia, Spain, UK, Uruguay, USA, and Vietnam, and associates from Chile, Denmark, Netherlands, and Norway.

  20. Rapid climate variability during warm and cold periods in polar regions and Europe

    DEFF Research Database (Denmark)

    Masson-Delmotte, V.; Landais, A.; Combourieu-Nebout, N.

    2005-01-01

    Typical rapid climate events punctuating the last glacial period in Greenland, Europe and Antarctica are compared to two rapid events occurring under warmer conditions: (i) Dansgaard-Oeschger event 25, the first abrupt warming occurring during last glacial inception; (ii) 8.2 ka BP event, the only...... rapid cooling recorded during the Holocene in Greenland ice cores and in Ammersee, Germany. The rate of warming during previous warmer interglacial periods is estimated from polar ice cores to 1.5 °C per millennium, without abrupt changes. Climate change expected for the 21st century should however...

  1. Photoproduction of positive pions from polarized protons in the region of the first resonance

    Energy Technology Data Exchange (ETDEWEB)

    Get' man, V.A.; Gorbenko, V.G.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Kuz' menko, V.S.; Lukhanin, A.A.; Ranyuk, Y.N.; Rubashkin, A.L.; Sanin, V.M.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.; Shalatskii, S.V.; Grushin, V.F.

    1980-04-01

    A technique for measuring the T asymmetry for the process ..gamma..p ..-->.. n..pi../sup +/ using a polarized proton target and a quasimonochromatic beam of photons is described. The results of measuring T in the range of pion-emission angles theta(/sub ..pi../ = 3 to 150/sup 0/ at a photon energy of 340 MeV are presented and discussed. It is shown that the results obtained allow a more reliable selection of the solutions of the energy-independent multipole analysis.

  2. What About Sea Ice? People, animals, and climate change in the polar regions: An online resource for the International Polar Year and beyond

    Science.gov (United States)

    Renfrow, S.; Meier, W. N.; Wolfe, J.; Scott, D.; Leon, A.; Weaver, R.

    2005-12-01

    Decreasing Arctic sea ice has been one of the most noticeable changes on Earth over the past quarter-century. The years 2002 through 2005 have had much lower summer sea ice extents than the long-term (1979-2000). Reduced sea ice extent has a direct impact on Arctic wildlife and people, as well as ramifications for regional and global climate. Students, educators, and the general public want and need to have a better understanding of sea ice. Most of us are unfamiliar with sea ice: what it is, where it occurs, and how it affects global climate. The upcoming International Polar Year will provide an opportunity for the public to learn about sea ice. Here, we provide an overview of sea ice, the changes that the sea ice is undergoing, and information about the relation between sea ice and climate. The information presented here is condensed from the National Snow and Ice Data Center's new 'All About Sea Ice' Web site (http://www.nsidc.org/seaice/), a comprehensive resource of information for sea ice.

  3. Innovative optical spectrometers for ice core sciences and atmospheric monitoring at polar regions

    Science.gov (United States)

    Grilli, Roberto; Alemany, Olivier; Chappellaz, Jérôme; Desbois, Thibault; Faïn, Xavier; Kassi, Samir; Kerstel, Erik; Legrand, Michel; Marrocco, Nicola; Méjean, Guillaume; Preunkert, Suzanne; Romanini, Daniele; Triest, Jack; Ventrillard, Irene

    2015-04-01

    In this talk recent developments accomplished from a collaboration between the Laboratoire Interdisciplinaire de Physique (LIPhy) and the Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE) both in Grenoble (France), are discussed, covering atmospheric chemistry of high reactive species in polar regions and employing optical spectrometers for both in situ and laboratory measurements of glacial archives. In the framework of an ANR project, a transportable spectrometer based on the injection of a broadband frequency comb laser into a high-finesse optical cavity for the detection of IO, BrO, NO2 and H2CO has been realized.[1] The robust spectrometer provides shot-noise limited measurements for as long as 10 minutes, reaching detection limits of 0.04, 2, 10 and 200 ppt (2σ) for the four species, respectively. During the austral summer of 2011/12 the instrument has been used for monitoring, for the first time, NO2, IO and BrO at Dumont d'Urville Station at East of Antarctica. The measurements highlighted a different chemistry between East and West coast, with the halogen chemistry being promoted to the West and the OH and NOx chemistry on the East.[2] In the framework of a SUBGLACIOR project, an innovative drilling probe has been realized. The instrument is capable of retrieving in situ real-time vertical profiles of CH4 and δD of H2O trapped inside the ice sheet down to more than 3 km of depth within a single Antarctic season. The drilling probe containing an embedded OFCEAS (optical-feedback cavity-enhanced absorption spectroscopy) spectrometer will be extremely useful for (i) identify potential sites for investigating the oldest ice (aiming 1.5 Myrs BP records for resolving a major climate reorganization called the Mid-Pleistocene transition occurred around 1 Myrs ago) and (ii) providing direct access to past temperatures and climate cycles thanks to the vertical distribution of two key climatic signatures.[3] The spectrometer provides detection

  4. Complex regional pain syndrome type I in the upper extremity - how efficient physical therapy and rehabilitation are.

    Science.gov (United States)

    Zečević Luković, Tanja; Ristić, Branko; Jovanović, Zorica; Rančić, Nemanja; Ignjatović Ristić, Dragana; Cuković, Saša

    2012-08-01

    To evaluate the effects of early started combined therapy in Complex Regional Pain Syndrome-1 (CRPS-1) on the upper extremities. The study included 36 patients in the first stadium of CRPS-1 on the upper extremities The mean age of patients was 42.6±14.6, the majority of them (26 of 36) were females. The right side of the upper extremity was affected much more then the left side. They were treated by combined therapy including analgetics, electrotherapy, magneto therapy and kinesitherapy. The average length of observation was 172.1 days (from 90 to 250 days). The average length of treatment was 91.5±42.16 days. Intensity of pain, swelling of the extremity, the change in skin coloration and cutaneous manifestations were assessed three times, at the beginning of the treatment, after 6 weeks and at the end of the treatment. The pain was registered in all patients at visit 1 (average pain intensity was 5.70 ±1.44 on 100 mm visual analogue scale), and it was progressively decreased during the treatment from 3.60±1.22 at the second visit to 0.34±0.68 at the third visit. Vasodilatation was registered in 30 (83.33%) patients and skin temperature asymmetries was found in 21 (58.33%) patients. The difference of size was detected in 30 (83.33%) patients at the first visit compared to four (11.11%) patients at the end of the treatment. There were six (16.66%) patients without swelling at the beginning compared to 26 (72.22%) at the end of the treatment (p less than 0.000). Complete healing was achieved in 32 patients (88.88%). The carefully chosen physical agents in combination with analgesic and non-steroidal anti-inflammatory drugs may benefit in patients with CRPS-1 on the upper extremity if the treatment starts as soon as possible.

  5. Environmental changes and human work in the region of the Upper Paraná River floodplain: processes and interactions

    Directory of Open Access Journals (Sweden)

    EA. Tomanik

    Full Text Available The environment and society constitute a complex of elements and interactions. Thus, an understanding of the processes in which the environment and psychosocial elements are involved may not be gained from knowledge of just one isolated variable. Based on such premises, the present paper, which summarizes the results of a series of studies, adopts work relationships as its main focus, but in addition, it has two complementary objectives. One is to present some analyses on the interaction between human actions and the environmental changes that have been taking place in the region of the Upper Paraná River floodplain and in its boundaries. A secondary aim is to show how those two factors have been changing people's working and living conditions and the identity configuration of some of the human groups that live at that site.

  6. A changing world: Using nuclear techniques to investigate the impact of climate change on polar and mountainous regions

    International Nuclear Information System (INIS)

    Henriques, Sasha

    2015-01-01

    Nuclear techniques are being used in polar and mountainous regions to study climate change and its impact on the quality of land, water and ecosystems in order to better conserve and manage these resources. Researchers from around the world will be using data from 13 benchmark sites to draw conclusions about the effects of the rapidly changing climate on the Arctic, mountains and the western part of Antarctica, which have alarmed communities, environmentalists, scientists and policy makers. Between July 2015 and July 2016 they will be using isotopic and nuclear techniques, as well as geochemical and biological analytical methods from other scientific disciplines. This will enable them to track soil and water, to monitor the movement of soil and sediment and to assess the effects of melting permafrost on the atmosphere, as well as on the land, water and fragile ecosystems of mountainous and polar regions. The measurements follow numerous on-site tests carried out since November 2014 to perfect the sampling technique.

  7. Decadal oscillation of lakes and aquifers in the upper Great Lakes region of North America: hydroclimatic implications

    Science.gov (United States)

    Watras, C.J.; Read, J.S.; Holman, K.D.; Liu, Z.; Song, Y.-Y.; Watras, A.J.; Morgan, S.; Stanley, E.H.

    2014-01-01

    We report a unique hydrologic time-series which indicates that water levels in lakes and aquifers across the upper Great Lakes region of North America have been dominated by a climatically-driven, near-decadal oscillation for at least 70 years. The historical oscillation (~13y) is remarkably consistent among small seepage lakes, groundwater tables and the two largest Laurentian Great Lakes despite substantial differences in hydrology. Hydrologic analyses indicate that the oscillation has been governed primarily by changes in the net atmospheric flux of water (P-E) and stage-dependent outflow. The oscillation is hypothetically connected to large-scale atmospheric circulation patterns originating in the mid-latitude North Pacific that support the flux of moisture into the region from the Gulf of Mexico. Recent data indicate an apparent change in the historical oscillation characterized by a ~12y downward trend beginning in 1998. Record low water levels region-wide may mark the onset of a new hydroclimatic regime.

  8. Spatial gradients in freshwater fish diversity, abundance and current pattern in the Himalayan region of Upper Ganges Basin, India

    Directory of Open Access Journals (Sweden)

    AJEY KUMAR PATHAK

    2014-10-01

    Full Text Available Pathak AK, Sarkar UK, Singh SP. 2014. Spatial gradients in freshwater fish diversity, abundance and current pattern in the Himalayan region of Upper Ganges Basin, India. Biodiversitas 15: 186-194.The present study describes the analysis and mapping of the different measurements of freshwater fish biodiversity of the Upper Ganges basin in the Himalayan region using spatial interpolation methods of Geographical Information System. The diversity, richness and abundance of fishes for each sampling location were determined and Kriging interpolation was applied on each fisheries measurement to predict and produce semivariogram. The semivariogarms produced were cross validated and reclassified. The reclassified maps for richness, abundance and diversity of fishes, occurrence of cold water threatened fish and abundance of important genera like Tor, Schziothorax and species were produced. The result of the Kriging produced good results and overall error in the estimation process was found significant. The cross validation of semovariograms also provided a better result with the observed data sets. Moreover, weighted overlay analysis of the reclassified raster maps of richness and abundance of fishes produced the classified raster map at different evaluation scale (0-10 qualitatively describing the gradient of species richness and abundance compositely. Similarly, the classified raster map at same evaluation scale qualitatively describing the gradient of species abundance and diversity compositely was produced and published. Further, basin wise analysis between Alaknanda/Pindar and Ganga1 sub basins showed 0.745 disparities at 0.745 distances in 2 dimensional spaces. The richness, diversity and abundance of threatened fishes among the different sampling locations were not significant (p = 0.9.

  9. Maternal health care initiatives: Causes of morbidities and mortalities in two rural districts of Upper West Region, Ghana.

    Directory of Open Access Journals (Sweden)

    Joshua Sumankuuro

    Full Text Available Maternal and neonatal morbidities and mortalities have received much attention over the years in sub-Saharan Africa; yet addressing them remains a profound challenge, no more so than in the nation of Ghana. This study focuses on finding explanations to the conditions which lead to maternal and neonatal morbidities and mortalities in rural Ghana, particularly the Upper West Region.Mixed methods approach was adopted to investigate the medical and non-medical causes of maternal and neonatal morbidities and mortalities in two rural districts of the Upper West Region of Ghana. Survey questionnaires, in-depth interviews and focus group discussions were employed to collect data from: a 80 expectant mothers (who were in their second and third trimesters, excluding those in their ninth month, b 240 community residents and c 13 healthcare providers (2 district directors of health services, 8 heads of health facilities and 3 nurses.Morbidity and mortality during pregnancy is attributed to direct causes such urinary tract infection (48%, hypertensive disorders (4%, mental health conditions (7%, nausea (4% and indirect related sicknesses such as anaemia (11%, malaria, HIV/AIDS, oedema and hepatitis B (26%. Socioeconomic and cultural factors are identified as significant underlying causes of these complications and to morbidity and mortality during labour and the postnatal period. Birth asphyxia and traditional beliefs and practices were major causes of neonatal deaths.These findings provide focused targets and open a window of opportunity for the community-based health services run by Ghana Health Service to intensify health education and promotion programmes directed at reducing risky economic activities and other cultural beliefs and practices affecting maternal and neonatal morbidity and mortality.

  10. Renewable energy in the heating sector in Austria with particular reference to the region of Upper Austria

    International Nuclear Information System (INIS)

    Kranzl, Lukas; Kalt, Gerald; Müller, Andreas; Hummel, Marcus; Egger, Christiane; Öhlinger, Christine; Dell, Gerhard

    2013-01-01

    The heating sector has been neglected in energy policies for quite some time, especially on the European level. Only recently, with the implementation of the European directive 2009/28/EC the sector has gained higher attention. The objective of this paper is to provide an overview of the heat market in Austria and of the current status and future prospects of renewable energy in the heat sector (RES-H) up to 2030. Despite the growing energy demand, the share of renewable energy in the total energy demand for space heating and hot water increased from about 20% in 1970 to about 34% in 2008. This is mainly due to ambitious RES-H support instruments and regional policy targets. For example, the government of the region of Upper Austria has implemented a target of 100% RES-H share in the space heating and hot water sector until the year 2030. However, the National Renewable Energy Action Plan for 2020 foresees only moderate growth rates for RES-H compared to recent market growth and scenarios in literature. Due to the ambitious targets and support schemes of regional governments it seems likely that RES-H deployment could growstronger than stated in the action plan. - Highlights: ► Overview on Austrian heat sector and RES-H development. ► Growing RES-H market mainly due to regional promotion schemes. ► Austrian NREAP foresees only moderate growth of RES-H up to 2020. ► Targets and policies on the regional level might lead to stronger RES-H deployment

  11. Photofission of NAT Pt by monochromatic and polarized photons in the quasi-deuteron region

    International Nuclear Information System (INIS)

    Paiva, Eduardo de.

    1992-01-01

    The measurement of the Nat Pt photofission yield at 69 MeV of effective average energy of the incident photon is made using a polarized and monochromatic photon beam from the LADON system of the National Laboratory of Frascati, Italy, produced by inverse Compton scattering of laser light by high energy electrons of the ADONE Accelerator and using as fission track solid detector the Makrofol, being the developing made by usual procedure. The experimental value of the nuclear fissionability is compared to a theoretical value obtained following a model at two stages: in the first, the photon energy is absorbed by a neutron-proton pair inducing to the nucleus excitation, and in the second the nucleus de-excites due to the competition between nucleon evaporation and fission. The effect of fast nucleon emission during the first stage and the successive evaporation of neutrons in the second stage are considered. 40 refs, 12 figs, 9 tabs

  12. Seasonal and regional differentiation of bio-optical properties within the north polar Atlantic

    Science.gov (United States)

    Stramska, Malgorzata; Stramski, Dariusz; Kaczmarek, SłAwomir; Allison, David B.; Schwarz, Jill

    2006-08-01

    Using field data from the north polar Atlantic, we examined seasonal variability of the spectral absorption, a(λ), and backscattering, bb(λ), coefficients of surface waters in relation to phytoplankton pigments. For a given chlorophyll a concentration, the concentrations of accessory pigments were lower in spring than in summer. This effect contributed to lower chlorophyll-specific absorption of phytoplankton and total particulate matter in spring. The spring values of the green-to-blue band ratio of a(λ) were higher than the summer ratios. The blue-to-green ratios of bb(λ) were also higher in spring. The higher bb values and lower blue-to-green bb ratios in summer were likely associated with higher concentrations of detrital particles in summer compared to spring. Because the product of these band ratios of a and bb is a proxy for the blue-to-green ratio of remote-sensing reflectance, the performance of ocean color band-ratio algorithms for estimating pigments is significantly affected by seasonal shifts in the relationships between absorption, backscattering, and chlorophyll a. Our results suggest that the algorithm for the spring season would predict chlorophyll a that is higher by as much as a factor of 4-6 compared to that predicted from the summer algorithm. This indicates a need for a seasonal approach in the north polar Atlantic. However, we also found that a fairly good estimate of the particulate beam attenuation coefficient at 660 nm (a proxy for total particulate matter or particulate organic carbon concentration) can be obtained by applying a single blue-to-green band-ratio algorithm regardless of the season.

  13. Pion elastic scattering from polarized 13C in the energy region of the P33 resonance

    International Nuclear Information System (INIS)

    Yifen, Yen

    1992-08-01

    Asymmetries (A y ) and differential cross sections (dσ/dΩ) were measured for π + and π - elastic scattering using polarized and unpolarized 13 C targets. The experiment was done at the Los Alamos Meson Physics Facility with the pion beam from the Low Energy Pion channel. The scattered pions were detected with the Large Acceptance Spectrometer. The 13 C nuclei in 13 C-enriched 1-butanol were polarized by the dynamic nuclear polarilization method. Angular distributions of both A y and dσ/dΩ were measured below the P 33 resonance at the incident energy of 130 MeV for π + and π - , and above the resonance at 223 MeV for π + and at 226 MeV for π - . In addition, A y and dσ/dΩ were measured in a range of momentum transfers, 1.75 ≤ q ≤ 2.05 fm - , at several energies. At 130 MeV, the values of A y are significantly different from zero for π - scattering. For π + at 130 MeV and for both π - and π + at all other energies, the A y are mostly consistent with zero. Theoretical analyses were done using different nuclear structure models. The data were not reproduced by the presently available nuclear wave functions. It was found that the asymmetry is strongly sensitive to the quadrupole spin flip part of the transition. The data of this thesis complement measurements of the magnetic form factor from electron scattering. In attempts to fit both the asymmetry and the magnetic form factor, it was found that the pion asymmetry data are not reproduced by the wavefunctions which fit the magnetic form factor at low momentum transfers

  14. Sedimentology of the Essaouira Basin (Meskala Field) in context of regional sediment distribution patterns during upper Triassic pluvial events

    Science.gov (United States)

    Mader, Nadine K.; Redfern, Jonathan; El Ouataoui, Majid

    2017-06-01

    Upper Triassic continental clastics (TAGI: Trias Argilo-Greseux Inferieur) in the Essaouira Basin are largely restricted to the subsurface, which has limited analysis of the depositional environments and led to speculation on potential provenance of the fluvial systems. Facies analysis of core from the Meskala Field onshore Essaouira Basin is compared with tentatively time-equivalent deposits exposed in extensive outcrops in the Argana Valley, to propose a process orientated model for local versus regional sediment distribution patterns in the continuously evolving Moroccan Atlantic rift during Carnian to Norian times. The study aims to unravel the climatic overprint and improve the understanding of paleo-climatic variations along the Moroccan Atlantic margin to previously recognised Upper Triassic pluvial events. In the Essaouira Basin, four facies associations representing a progressive evolution from proximal to distal facies belts in a continental rift were established. Early ephemeral braided river systems are succeeded by a wet aeolian sandflat environment with a strong arid climatic overprint (FA1). This is followed by the onset of perennial fluvial deposits with extensive floodplain fines (FA2), accompanied by a distinct shift in fluvial style, suggesting increase in discharge and related humidity, either locally or in the catchment area. The fluvial facies transitions to a shallow lacustrine or playa lake delta environment (FA3), which exhibits cyclical abandonment. The delta is progressively overlain by a terminal playa with extensive, mottled mudstones (FA4), interpreted to present a return from cyclical humid-arid conditions to prevailing aridity in the basin. In terms of regional distribution and sediment source provenance, paleocurrent data from Carnian to Norian deposits (T5 to T8 member) in the Argana Valley suggest paleoflow focused towards the S and SW, not directed towards the Meskala area in the NW as previously suggested. A major depo

  15. Nuclear polarization and neutrons

    International Nuclear Information System (INIS)

    Glaettli, H.

    1985-01-01

    Different possibilities for the use of polarized nuclei in thermal neutron scattering on condensed matter are reviewed. Highly polarized nuclei are the starting point for studying dipolar magnetic order. Systematic measurement of spin-dependent scattering lengths is possible on samples with polarized nuclei. Highly polarized hydrogen should help to unravel complicated structures in chemistry and biology. The use of polarized proton targets as an energy-independent neutron polarizer in the thermal and epithermal region should be considered afresh. (author)

  16. Chronology and ancient feeding ecology of two upper Pleistocene megamammals from the Brazilian Intertropical Region

    Science.gov (United States)

    de Melo França, Lucas; Trindade Dantas, Mário André; Bocchiglieri, Adriana; Cherckinsky, Alexander; de Souza Ribeiro, Adauto; Bocherens, Hervé

    2014-09-01

    In Brazilian Intertropical Region (BIR) fossil remains of the giant ground sloth Eremotherium laurillardi (Lund, 1842) and of the proboscidean Notiomastodon platensis (Ameghino, 1888) are the most abundant among megaherbivores. However, the paleoecology of both species needs to be better understood to enlighten why these species disappear in the end of the Pleistocene, an issue that is still debated. During the last decades, the carbon and oxygen stable isotopes have been increasingly being used to obtain paleoecological information about extinct animals, although this information is in most cases dissociated from chronological data. Thus, the main objective of this study is to contribute to the knowledge about feeding ecology and chronology of E. laurillardi and N. platensis within BIR. For each fossil sample we performed stable isotopes analyses (δ13C/δ18O) and radiocarbon dating (14C with AMS). The results showed that N. platensis occurred between 12,125 and 19,594 cal yr BP and exhibited a grazer diet (δ13C = -1.1‰-1.3‰), while E. laurillardi lived between 11,084 and 27,690 cal yr BP, with a mixed feeder diet (C3/C4 plants; values ratio δ13C = -7.7‰ to -3.3‰). The δ18O values of N. platensis ranged between 2.20‰ and 3.60‰, while the values of E. laurillardi ranged between -3.10‰ and -1.10‰. Neither species did exhibit differences in its diet through time, which suggests that the vegetational composition of this locality did not vary in the late Pleistocene. Both species were living in an open environment, rich in herbaceous plants (C4 plants) and with tree and shrub with disjoint distribution, maybe similar to some parts of recent Caatinga, where they have partitioned the spatial and feeding niches.

  17. Extended high circular polarization in the Orion massive star forming region: implications for the origin of homochirality in the solar system.

    Science.gov (United States)

    Fukue, Tsubasa; Tamura, Motohide; Kandori, Ryo; Kusakabe, Nobuhiko; Hough, James H; Bailey, Jeremy; Whittet, Douglas C B; Lucas, Philip W; Nakajima, Yasushi; Hashimoto, Jun

    2010-06-01

    We present a wide-field (approximately 6' x 6') and deep near-infrared (K(s) band: 2.14 mum) circular polarization image in the Orion nebula, where massive stars and many low-mass stars are forming. Our results reveal that a high circular polarization region is spatially extended (approximately 0.4 pc) around the massive star-forming region, the BN/KL nebula. However, other regions, including the linearly polarized Orion bar, show no significant circular polarization. Most of the low-mass young stars do not show detectable extended structure in either linear or circular polarization, in contrast to the BN/KL nebula. If our solar system formed in a massive star-forming region and was irradiated by net circularly polarized radiation, then enantiomeric excesses could have been induced, through asymmetric photochemistry, in the parent bodies of the meteorites and subsequently delivered to Earth. These could then have played a role in the development of biological homochirality on Earth.

  18. Solar Lyman-Alpha Polarization Observation of the Chromosphere and Transition Region by the Sounding Rocket Experiment CLASP

    Science.gov (United States)

    Narukage, Noriyuki; Kano, Ryohei; Bando, Takamasa; Ishikawa, Ryoko; Kubo, Masahito; Katsukawa, Yukio; Ishikawa, Shinnosuke; Hara, Hiroshi; Suematsu, Yoshinori; Giono, Gabriel; hide

    2015-01-01

    We are planning an international rocket experiment Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is (2015 planned) that Lyman a line (Ly(alpha) line) polarization spectroscopic observations from the sun. The purpose of this experiment, detected with high accuracy of the linear polarization of the Ly(alpha) lines to 0.1% by using a Hanle effect is to measure the magnetic field of the chromosphere-transition layer directly. For polarization photometric accuracy achieved that approx. 0.1% required for CLASP, it is necessary to realize the monitoring device with a high throughput. On the other hand, Ly(alpha) line (vacuum ultraviolet rays) have a sensitive characteristics that is absorbed by the material. We therefore set the optical system of the reflection system (transmission only the wavelength plate), each of the mirrors, subjected to high efficiency of the multilayer coating in accordance with the role. Primary mirror diameter of CLASP is about 30 cm, the amount of heat about 30,000 J is about 5 minutes of observation time is coming mainly in the visible light to the telescope. In addition, total flux of the sun visible light overwhelmingly large and about 200 000 times the Ly(alpha) line wavelength region. Therefore, in terms of thermal management and 0.1% of the photometric measurement accuracy achieved telescope, elimination of the visible light is essential. We therefore, has a high reflectivity (> 50%) in Lya line, visible light is a multilayer coating be kept to a low reflectance (Science was achieved a high throughput as a device for a vacuum ultraviolet ray of the entire system less than 5% (CCD of QE is not included).

  19. The freshwater balance of polar regions in transient simulations from 1500 to 2100 AD using a comprehensive coupled climate model

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, Flavio; Raible, Christoph C.; Hofer, Dominik; Stocker, Thomas F. [University of Bern, Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, Bern (Switzerland)

    2012-07-15

    The ocean and sea ice in both polar regions are important reservoirs of freshwater within the climate system. While the response of these reservoirs to future climate change has been studied intensively, the sensitivity of the polar freshwater balance to natural forcing variations during preindustrial times has received less attention. Using an ensemble of transient simulations from 1500 to 2100 AD we put present-day and future states of the polar freshwater balance in the context of low frequency variability of the past five centuries. This is done by focusing on different multi-decadal periods of characteristic external forcing. In the Arctic, freshwater is shifted from the ocean to sea ice during the Maunder Minimum while the total amount of freshwater within the Arctic domain remains unchanged. In contrast, the subsequent Dalton Minimum does not leave an imprint on the slow-reacting reservoirs of the ocean and sea ice, but triggers a drop in the import of freshwater through the atmosphere. During the twentieth and twenty-first century the build-up of freshwater in the Arctic Ocean leads to a strengthening of the liquid export. The Arctic freshwater balance is shifted towards being a large source of freshwater to the North Atlantic ocean. The Antarctic freshwater cycle, on the other hand, appears to be insensitive to preindustrial variations in external forcing. In line with the rising temperature during the industrial era the freshwater budget becomes increasingly unbalanced and strengthens the high latitude's Southern Ocean as a source of liquid freshwater to lower latitude oceans. (orig.)

  20. Strategic Location and Territorial Integrity: The Role of Subsidiary Sites in the Classic Maya Kingdoms of the Upper Usumacinta Region

    Directory of Open Access Journals (Sweden)

    Armando Anaya Hernández

    2006-03-01

    Full Text Available The Upper Usumacinta region was the scene of an intense interaction between the different kingdoms of the Classic Maya Period. This interaction took the form of political and marriage alliances as well as warfare and is well attested in the inscribed monuments of the region, especially towards the Late Classic Period (c. AD 600-900. Through this interaction the Maya rulers would not only assert their claim to power but also ensure the boundaries of their kingdoms, with an eye to accruing a vaster domain. The definition of the political organisation and territorial extent of the Maya Lowland kingdoms is an issue that has attracted the attention of various scholars (Adams 1981; Adams and Jones 1981; Ball and Taschek 1991; Flannery 1972; Freidel 1981; Hammond 1974; 1981; Inomata and Aoyama 1996; Mathews 1988; 1991; Sanders 1981. Like these scholars, I have presented a model aimed at estimating the territorial extent of the kingdoms of the Upper Usumacinta region, taking into account the physical characteristics of the terrain (Anaya Hernández 2001. In this article I approach this issue again, focusing this time on the importance that the subsidiary centres located at strategic locations across the landscape had for the maintenance of the territorial integrity of the kingdoms of Pomoná and Piedras Negras. The political importance of these sites is reflected in the efforts that the kings of these polities went through to warrant the loyalty of the rulers of these secondary centres, as can be attested by the presence of a sculptured stela at the site of Panhalé, in the vicinity of Pomoná, and an inscribed wooden box found within the Redención del Campesino Valley that makes reference to a Piedras Negras ruler. To address this issue I took advantage of the capabilities that GIS offers to model movement across the physical setting in order to define the potential boundaries between the aforementioned kingdoms in the light of the available

  1. Regional paleohydrologic and paleoclimatic settings of wetland/lacustrine depositional systems in the Morrison Formation (Upper Jurassic), Western Interior, USA

    Science.gov (United States)

    Dunagan, S.P.; Turner, C.E.

    2004-01-01

    During deposition of the Upper Jurassic Morrison Formation, water that originated as precipitation in uplands to the west of the Western Interior depositional basin infiltrated regional aquifers that underlay the basin. This regional groundwater system delivered water into the otherwise dry continental interior basin where it discharged to form two major wetland/lacustrine successions. A freshwater carbonate wetland/lacustrine succession formed in the distal reaches of the basin, where regional groundwater discharged into the Denver-Julesburg Basin, which was a smaller structural basin within the more extensive Western Interior depositional basin. An alkaline-saline wetland/lacustrine complex (Lake T'oo'dichi') formed farther upstream, where shallower aquifers discharged into the San Juan/Paradox Basin, which was another small structural basin in the Western Interior depositional basin. These were both wetlands in the sense that groundwater was the major source of water. Input from surface and meteoric water was limited. In both basins, lacustrine conditions developed during episodes of increased input of surface water. Inclusion of wetlands in our interpretation of what had previously been considered largely lacustrine systems has important implications for paleohydrology and paleoclimatology. The distal carbonate wetland/lacustrine deposits are well developed in the Morrison Formation of east-central Colorado, occupying a stratigraphic interval that is equivalent to the "lower" Morrison but extends into the "upper" Morrison Formation. Sedimentologic, paleontologic, and isotopic evidence indicate that regional groundwater discharge maintained shallow, hydrologically open, well oxygenated, perennial carbonate wetlands and lakes despite the semi-arid climate. Wetland deposits include charophyte-rich wackestone and green mudstone. Lacustrine episodes, in which surface water input was significant, were times of carbonate and siliciclastic deposition in scarce deltaic

  2. High Resolution Topography of Polar Regions from Commercial Satellite Imagery, Petascale Computing and Open Source Software

    Science.gov (United States)

    Morin, Paul; Porter, Claire; Cloutier, Michael; Howat, Ian; Noh, Myoung-Jong; Willis, Michael; Kramer, WIlliam; Bauer, Greg; Bates, Brian; Williamson, Cathleen

    2017-04-01

    Surface topography is among the most fundamental data sets for geosciences, essential for disciplines ranging from glaciology to geodynamics. Two new projects are using sub-meter, commercial imagery licensed by the National Geospatial-Intelligence Agency and open source photogrammetry software to produce a time-tagged 2m posting elevation model of the Arctic and an 8m posting reference elevation model for the Antarctic. When complete, this publically available data will be at higher resolution than any elevation models that cover the entirety of the Western United States. These two polar projects are made possible due to three equally important factors: 1) open-source photogrammetry software, 2) petascale computing, and 3) sub-meter imagery licensed to the United States Government. Our talk will detail the technical challenges of using automated photogrammetry software; the rapid workflow evolution to allow DEM production; the task of deploying the workflow on one of the world's largest supercomputers; the trials of moving massive amounts of data, and the management strategies the team needed to solve in order to meet deadlines. Finally, we will discuss the implications of this type of collaboration for future multi-team use of leadership-class systems such as Blue Waters, and for further elevation mapping.

  3. Signatures of the high-altitude polar cusp and dayside auroral regions as seen by the Viking electric field experiment

    International Nuclear Information System (INIS)

    Marklund, G.T.; Blomberg, L.G.; Faelthammar, C.G.; Erlandson, R.E.; Potemra, T.A.

    1990-01-01

    Electric field and satellite potential observations along 42 Viking orbits in the high-altitude (2R E ) polar cusp and dayside auroral region have been examined. Within the cusp the plasma density usually reaches a maximum, and it is typically very homogeneous, in contrast to the irregular and lower density in the cleft and dayside auroral regions. The maxima in the plasma density are sometimes anticorrelated with the magnetic field strength, indicating a diamagnetic effect. The entire cusp and dayside auroral regions are characterized by irregular and burstlike electric fields, comprising field reversals on various scales (up to 3 min or 500 km), the larger scales, however, being rare in the cusp. Another common feature in these regions is the high correlation between mutually orthogonal components of the electric and magnetic fields, both for large-scale variations across spatial structures and for wave and pulsations in the ULF frequency range. The electric field signatures in the cusp (in the 1100-1300 MLT sector) are, however, characteristically different from the cleft and oval field signatures in that the electric field is usually less intense and less structured and not correlated with the substorm activity level

  4. Brain region-specific perfluoroalkylated sulfonate (PFSA) and carboxylic acid (PFCA) accumulation and neurochemical biomarker responses in east Greenland polar bears (Ursus maritimus)

    DEFF Research Database (Denmark)

    Pedersen, Kathrine Eggers; Basu, Niladri; Letcher, Robert J.

    2015-01-01

    to bioaccumulate in lipid rich tissues of the brain among other tissues such as liver, and can reach high concentrations in top predators including the polar bear. PFCA and PFSA bioaccummulation in the brain has the potential to pose neurotoxic effects and therefore we conducted a study to investigate...... if variations in neurochemical transmitter systems i.e. the cholinergic, glutaminergic, dopaminergic and GABAergic, could be related to brain-specific bioaccumulation of PFASs in East Greenland polar bears. Nine brain regions from nine polar bears were analyzed for enzyme activity (monoamine oxidase (MAO...... regions, whereas GS activity was positively correlated with PFASs primarily in occipital lobe. Results from the present study support the hypothesis that PFAS concentrations in polar bears from East Greenland have exceeded the threshold limits for neurochemical alterations. It is not known whether...

  5. Neutron polarization

    International Nuclear Information System (INIS)

    Firk, F.W.K.

    1976-01-01

    Some recent experiments involving polarized neutrons are discussed; they demonstrate how polarization studies provide information on fundamental aspects of nuclear structure that cannot be obtained from more traditional neutron studies. Until recently, neutron polarization studies tended to be limited either to very low energies or to restricted regions at higher energies, determined by the kinematics of favorable (p, vector n) and (d, vector n) reactions. With the advent of high intensity pulsed electron and proton accelerators and of beams of vector polarized deuterons, this is no longer the case. One has entered an era in which neutron polarization experiments are now being carried out, in a routine way, throughout the entire range from thermal energies to tens-of-MeV. The significance of neutron polarization studies is illustrated in discussions of a wide variety of experiments that include the measurement of T-invariance in the β-decay of polarized neutrons, a search for the effects of meson exchange currents in the photo-disintegration of the deuteron, the determination of quantum numbers of states in the fission of aligned 235 U and 237 Np induced by polarized neutrons, and the double- and triple-scattering of fast neutrons by light nuclei

  6. Relationship between geohydrology and Upper Pleistocene-Holocene evolution of the eastern region of the Province of Buenos Aires, Argentina

    Science.gov (United States)

    Capítulo, Leandro Rodrigues; Kruse, Eduardo E.

    2017-07-01

    The Upper Pleistocene-Holocene geological evolution, which is characterized by its landscape-forming energy and is related to geological and geomorphological complexity, has an impact on the groundwater dynamics of coastal aquifers. The geological configuration of a sector of the east coast of the Province of Buenos Aires was analyzed, as well as its connection with the geological and geomorphological history of the region during the Late Pleistocene and Holocene, and its influence on the regional and local geohydrological behaviour. This analysis was based on the application of the concept of hydrofacies. Boreholes were drilled and sampled (with depths of up to 40 m), and vertical electrical sounding, electrical tomography and pumping tests were undertaken. The description of the cutting samples by means of a stereo microscope, the interpretation of satellite images, and the construction of lithological and hydrogeological profiles and flow charts were carried out in the laboratory, and then integrated in a GIS. The identification of the lithological units and their distribution in the area allowed the construction of an evolutionary geological model for the Late Pleistocene and Holocene. Three aquifer units can be recognized: one of Late Pleistocene age (hydrofacies E) and the other two of Holocene age (hydrofacies A and C); their hydraulic connection depends on the occurrence and thickness variation of the aquitard units (hydrofacies B and D). The approach adopted allows the examination of the possibilities for groundwater exploitation and constitutes an applied conceptual framework to be taken into consideration when developing conceptual and numerical models at the local and regional scales.

  7. Regional and temporal variations in coding of hospital diagnoses referring to upper gastrointestinal and oesophageal bleeding in Germany

    Directory of Open Access Journals (Sweden)

    Garbe Edeltraut

    2011-08-01

    Full Text Available Abstract Background Health insurance claims data are increasingly used for health services research in Germany. Hospital diagnoses in these data are coded according to the International Classification of Diseases, German modification (ICD-10-GM. Due to the historical division into West and East Germany, different coding practices might persist in both former parts. Additionally, the introduction of Diagnosis Related Groups (DRGs in Germany in 2003/2004 might have changed the coding. The aim of this study was to investigate regional and temporal variations in coding of hospitalisation diagnoses in Germany. Methods We analysed hospitalisation diagnoses for oesophageal bleeding (OB and upper gastrointestinal bleeding (UGIB from the official German Hospital Statistics provided by the Federal Statistical Office. Bleeding diagnoses were classified as "specific" (origin of bleeding provided or "unspecific" (origin of bleeding not provided coding. We studied regional (former East versus West Germany differences in incidence of hospitalisations with specific or unspecific coding for OB and UGIB and temporal variations between 2000 and 2005. For each year, incidence ratios of hospitalisations for former East versus West Germany were estimated with log-linear regression models adjusting for age, gender and population density. Results Significant differences in specific and unspecific coding between East and West Germany and over time were found for both, OB and UGIB hospitalisation diagnoses, respectively. For example in 2002, incidence ratios of hospitalisations for East versus West Germany were 1.24 (95% CI 1.16-1.32 for specific and 0.67 (95% CI 0.60-0.74 for unspecific OB diagnoses and 1.43 (95% CI 1.36-1.51 for specific and 0.83 (95% CI 0.80-0.87 for unspecific UGIB. Regional differences nearly disappeared and time trends were less marked when using combined specific and unspecific diagnoses of OB or UGIB, respectively. Conclusions During the study

  8. Chemical cycling and deposition of atmospheric mercury in polar regions: review of recent measurements and comparison with models

    Directory of Open Access Journals (Sweden)

    H. Angot

    2016-08-01

    Full Text Available Mercury (Hg is a worldwide contaminant that can cause adverse health effects to wildlife and humans. While atmospheric modeling traces the link from emissions to deposition of Hg onto environmental surfaces, large uncertainties arise from our incomplete understanding of atmospheric processes (oxidation pathways, deposition, and re-emission. Atmospheric Hg reactivity is exacerbated in high latitudes and there is still much to be learned from polar regions in terms of atmospheric processes. This paper provides a synthesis of the atmospheric Hg monitoring data available in recent years (2011–2015 in the Arctic and in Antarctica along with a comparison of these observations with numerical simulations using four cutting-edge global models. The cycle of atmospheric Hg in the Arctic and in Antarctica presents both similarities and differences. Coastal sites in the two regions are both influenced by springtime atmospheric Hg depletion events and by summertime snowpack re-emission and oceanic evasion of Hg. The cycle of atmospheric Hg differs between the two regions primarily because of their different geography. While Arctic sites are significantly influenced by northern hemispheric Hg emissions especially in winter, coastal Antarctic sites are significantly influenced by the reactivity observed on the East Antarctic ice sheet due to katabatic winds. Based on the comparison of multi-model simulations with observations, this paper discusses whether the processes that affect atmospheric Hg seasonality and interannual variability are appropriately represented in the models and identifies research gaps in our understanding of the atmospheric Hg cycling in high latitudes.

  9. ARCAD3-SAFARI coordinated study of auroral and polar F-region ionospheric irregularities

    International Nuclear Information System (INIS)

    Villain, J.P.; Hanuise, C.

    1986-01-01

    Simultaneous observations of F-region ionospheric irregularities have been performed with the SAFARI ground-based HF radars and the ISOPROBE experiment on board the AUREOL-3 satellite. Among seven orbits during which the satellite trajectory was directly in the radar beam or in the vicinity, four of them have been analyzed in detail. The spectral power of the electron density variations ΔNsub(e)/Nsub(e) has been calculated for wavelengths between 20 m and 1 km from the isoprobe high time resolution thermal plasma measurements. One spectrum is obtained every 1.2 s, a time which corresponds to about 10 km along the satellite trajectory. The presence of echoes observed in the F-region with the SAFARI radars is compared with the spectral power of the electron density variations deduced from the ISOPROBE ''in situ'' measurements. A good agreement is found between the two sets of observations and a numerical value of the spectral power corresponding to detection of echoes by the radar is given. A synoptical view of the event is given and interpreted according to the existing theories of plasma irregularities

  10. Magnetic field configurations associated with polarity intrusion in a solar active region

    International Nuclear Information System (INIS)

    Low, B.C.

    1982-01-01

    This paper presents a new class of exact solutions describing the non-linear force-free-field above a spatially localized photospheric bipolar magnetic region. An essential feature is the variation in all three Cartesian directions and this could not be modelled adequately with previously known symmetric force-free fields. Sequences of force-free fields are constructed and analyzed to simulate the slow growth of a pair of spots on the photosphere. The acis connecting the spots executes roational motion, distorting the photospheric neutral line separating fluxes of opposite signs. We show directly from the analytic solutions that the resulting reversal of the positions of the spots relative to the background field is associated with (i) the creation of magnetic free energy, (ii) the severe shearing of localized low-lying loops in the vicinity where the photospheric transverse field aligns with the photospheric neutral line, and (iii) the emergence and disappearance of flux from the photosphere at these highly stressed regions. The model relates theoretically for the first time these different magnetic field features that have been suggested by observation and theoretical considerations to be flare precursors. A general formula, based on the virial theorem, is also given for the free energy of a force-free field, strictly in terms of the field value at the photosphere. This formula has obvious practical application. (orig.)

  11. Food as a social determinant of mental health among household heads in the Upper West Region of Ghana.

    Science.gov (United States)

    Atuoye, Kilian Nasung; Luginaah, Isaac

    2017-05-01

    According to the World Health Organization, mental distress and related illnesses are becoming leading causes of morbidity and mortality in developing countries. Despite the influence of food insecurity on mental health, empirical understanding of this relationship in sub-Saharan Africa, where incidence of food insecurity is relatively high, is almost non-existent. This study contributes to the literature by examining the association between food insecurity and mental health in the Upper West Region of Ghana. We used Ordinary Least Square (OLS) to analyze cross-sectional data collected on household heads (n = 1438) in 2014 using the Household Food Insecurity Access Scale and the DUKE Health Profile. The results show that heads of severely food insecure (β = 0.934, p ≤ 0.001) and moderately food secure households (β = 0.759, p ≤ 0.001) were more likely to report elevated mental distress compared to those from food secure households. We also found that female household heads were more likely to report elevated mental distress (β = 0.164, p ≤ 0.05) compared to their male counterparts. Our findings suggest the need to improve food security as a strategy targeted at improving overall mental health in the Ghanaian context. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Change in frozen soils and its effect on regional hydrology, upper Heihe basin, northeastern Qinghai-Tibetan Plateau

    Science.gov (United States)

    Gao, Bing; Yang, Dawen; Qin, Yue; Wang, Yuhan; Li, Hongyi; Zhang, Yanlin; Zhang, Tingjun

    2018-02-01

    Frozen ground has an important role in regional hydrological cycles and ecosystems, particularly on the Qinghai-Tibetan Plateau (QTP), which is characterized by high elevations and a dry climate. This study modified a distributed, physically based hydrological model and applied it to simulate long-term (1971-2013) changes in frozen ground its the effects on hydrology in the upper Heihe basin, northeastern QTP. The model was validated against data obtained from multiple ground-based observations. Based on model simulations, we analyzed spatio-temporal changes in frozen soils and their effects on hydrology. Our results show that the area with permafrost shrank by 8.8 % (approximately 500 km2), predominantly in areas with elevations between 3500 and 3900 m. The maximum depth of seasonally frozen ground decreased at a rate of approximately 0.032 m decade-1, and the active layer thickness over the permafrost increased by approximately 0.043 m decade-1. Runoff increased significantly during the cold season (November-March) due to an increase in liquid soil moisture caused by rising soil temperatures. Areas in which permafrost changed into seasonally frozen ground at high elevations showed especially large increases in runoff. Annual runoff increased due to increased precipitation, the base flow increased due to changes in frozen soils, and the actual evapotranspiration increased significantly due to increased precipitation and soil warming. The groundwater storage showed an increasing trend, indicating that a reduction in permafrost extent enhanced the groundwater recharge.

  13. Role of the Land Valuation Division in Property Rating by District Assemblies in Ghana's Upper East Region

    Directory of Open Access Journals (Sweden)

    Maxwell Kwotua Petio

    2013-05-01

    Full Text Available District Assemblies in Ghana are charged with the responsibility of developing their areas of jurisdiction mainly through internally mobilised revenue. As a consequence, the assemblies are empowered by various pieces of legislation to impose local taxes within their jurisdiction. The local taxes include property rates which are a form of tax that only the District Assemblies may levy. The study therefore looked at the levying of property rates in the Upper East Region and assessed the role and institutional capacity of the Land Valuation Division of the Lands Commission in the tax administration. Findings included limited coverage of the tax, use of flat rates due to absence of up-to-date property values, inadequate technical personnel and logistics for the Land Valuation Division (LVD and lack of political will to levy the rates fully. Relevant suggestions are made, such as the need to introduce mass valuation, widen the tax coverage, establish a fund for revaluation and revive the Valuation Training School, as well as provide requisite logistics for efficient performance of the LVD.

  14. Review of emergency obstetric care interventions in health facilities in the Upper East Region of Ghana: a questionnaire survey.

    Science.gov (United States)

    Kyei-Onanjiri, Minerva; Carolan-Olah, Mary; Awoonor-Williams, John Koku; McCann, Terence V

    2018-03-15

    Maternal morbidity and mortality is most prevalent in resource-poor settings such as sub-Saharan Africa and southern Asia. In sub-Saharan Africa, Ghana is one of the countries still facing particular challenges in reducing its maternal morbidity and mortality. Access to emergency obstetric care (EmOC) interventions has been identified as a means of improving maternal health outcomes. Assessing the range of interventions provided in health facilities is, therefore, important in determining capacity to treat obstetric emergencies. The aim of this study was to examine the availability of emergency obstetric care interventions in the Upper East Region of Ghana. A cross-sectional survey of 120 health facilities was undertaken. Status of emergency obstetric care was assessed through an interviewer administered questionnaire to directors/in-charge officers of maternity care units in selected facilities. Data were analysed using descriptive statistics. Eighty per cent of health facilities did not meet the criteria for provision of emergency obstetric care. Comparatively, private health facilities generally provided EmOC interventions less frequently than public health facilities. Other challenges identified include inadequate skill mix of maternity health personnel, poor referral processes, a lack of reliable communication systems and poor emergency transport systems. Multiple factors combine to limit women's access to a range of essential maternal health services. The availability of EmOC interventions was found to be low across the region; however, EmOC facilities could be increased by nearly one-third through modest investments in some existing facilities. Also, the key challenges identified in this study can be improved by enhancing pre-existing health system structures such as Community-based Health Planning and Services (CHPS), training more midwifery personnel, strengthening in-service training and implementation of referral audits as part of health service

  15. Simulation of river plume behaviors in a tropical region: Case study of the Upper Gulf of Thailand

    Science.gov (United States)

    Yu, Xiaojie; Guo, Xinyu; Morimoto, Akihiko; Buranapratheprat, Anukul

    2018-02-01

    River plumes are a general phenomenon in coastal regions. Most previous studies focus on river plumes in middle and high latitudes with few studies examining those in low latitude regions. Here, we apply a numerical model to the Upper Gulf of Thailand (UGoT) to examine a river plume in low latitudes. Consistent with observational data, the modeled plume has seasonal variation dependent on monsoon conditions. During southwesterly monsoons, the plume extends northeastward to the head of the gulf; during northeasterly monsoons, it extends southwestward to the mouth of the gulf. To examine the effects of latitude, wind and river discharge on the river plume, we designed several numerical experiments. Using a middle latitude for the UGoT, the bulge close to the river mouth becomes smaller, the downstream current flows closer to the coast, and the salinity in the northern UGoT becomes lower. The reduction in the size of the bulge is consistent with the relationship between the offshore distance of a bulge and the Coriolis parameter. Momentum balance of the coastal current is maintained by advection, the Coriolis force, pressure gradient and internal stresses in both low and middle latitudes, with the Coriolis force and pressure gradient enlarged in the middle latitude. The larger pressure gradient in the middle latitude is induced by more offshore freshwater flowing with the coastal current, which induces lower salinity. The influence of wind on the river plume not only has the advection effects of changing the surface current direction and increasing the surface current speed, but also decreases the current speed due to enhanced vertical mixing. Changes in river discharge influence stratification in the UGoT but have little effect on the behavior of the river plume.

  16. PoLAR Voices: Informing Adult Learners about the Science and Story of Climate Change in the Polar Regions Through Audio Podcast

    Science.gov (United States)

    Quinney, A.; Murray, M. S.; Gobroski, K. A.; Topp, R. M.; Pfirman, S. L.

    2015-12-01

    The resurgence of audio programming with the advent of podcasting in the early 2000s spawned a new medium for communicating advances in science, research, and technology. To capitalize on this informal educational outlet, the Arctic Institute of North America partnered with the International Arctic Research Center, the University of Alaska Fairbanks, and the UA Museum of the North to develop a podcast series called PoLAR Voices for the Polar Learning and Responding (PoLAR) Climate Change Education Partnership. PoLAR Voices is a public education initiative that uses creative storytelling and novel narrative structures to immerse the listener in an auditory depiction of climate change. The programs will feature the science and story of climate change, approaching topics from both the points of view of researchers and Arctic indigenous peoples. This approach will engage the listener in the holistic story of climate change, addressing both scientific and personal perspectives, resulting in a program that is at once educational, entertaining and accessible. Feedback is being collected at each stage of development to ensure the content and format of the program satisfies listener interests and preferences. Once complete, the series will be released on thepolarhub.org and on iTunes. Additionally, blanket distribution of the programs will be accomplished via radio broadcast in urban, rural and remote areas, and in multiple languages to increase distribution and enhance accessibility.

  17. DUST IN THE POLAR REGION AS A MAJOR CONTRIBUTOR TO THE INFRARED EMISSION OF ACTIVE GALACTIC NUCLEI

    Energy Technology Data Exchange (ETDEWEB)

    Hoenig, S. F.; Antonucci, R. [Department of Physics, University of California in Santa Barbara, Broida Hall, Santa Barbara, CA 93109 (United States); Kishimoto, M.; Tristram, K. R. W.; Asmus, D.; Weigelt, G. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany); Prieto, M. A. [Instituto de Astrofisica de Canarias, E-38200 La Laguna, Tenerife (Spain); Gandhi, P. [Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Burtscher, L. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrae, D-85748 Garching (Germany); Duschl, W. J., E-mail: shoenig@physics.ucsb.edu [Institut fuer Theoretische Physik und Astrophysik, Christian-Albrechts-Universitaet zu Kiel, Leibnizstr. 15, D-24098, Kiel (Germany)

    2013-07-10

    Dust around active galactic nuclei (AGNs) is distributed over a wide range of spatial scales and can be observed in the infrared (IR). It is generally assumed that the distribution on parsec scales forms a geometrically and optically thick entity in the equatorial plane around the accretion disk and broad-line region-dubbed {sup d}ust torus{sup -}that emits the bulk of the subarcsecond-scale IR emission and gives rise to orientation-dependent obscuration. However, recent IR interferometry studies with unprecedented position angle (P.A.) and baseline coverage on these small scales in two obscured (type 2) AGNs have revealed that the majority of the mid-IR emission in these objects is elongated in the polar direction. These observations are difficult to reconcile with the standard interpretation that most of the parsec-scale mid-IR emission in AGNs originate from the torus and challenges the justification of using simple torus models to model the broadband IR emission. Here, we report detailed interferometry observations of the unobscured (type 1) AGN in NGC 3783 that allow us to constrain the size, elongation, and direction of the mid-IR emission with high accuracy. The mid-IR emission is characterized by a strong elongation toward position angle P.A. -52 Degree-Sign , closely aligned with the polar axis (P.A. -45 Degree-Sign ). We determine half-light radii along the major and minor axes at 12.5 {mu}m of (20.0 {+-} 3.0) mas Multiplication-Sign (6.7 {+-} 1.0) mas or (4.23 {+-} 0.63) pc Multiplication-Sign (1.42 {+-} 0.21) pc, which corresponds to intrinsically scaled sizes of (69.4 {+-} 10.8) r{sub in} Multiplication-Sign (23.3 {+-} 3.5) r{sub in} for the inner dust radius of r{sub in} = 0.061 pc as inferred from near-IR reverberation mapping. This implies an axis ratio of 3:1, with about 60%-90% of the 8-13 {mu}m emission associated with the polar-elongated component. It is quite likely that the hot-dust emission as recently resolved by near-IR interferometry is

  18. Semi-automatic measures of activity in selected south polar regions of Mars using morphological image analysis

    Science.gov (United States)

    Aye, Klaus-Michael; Portyankina, Ganna; Pommerol, Antoine; Thomas, Nicolas

    The High Resolution Imaging Science Experiment (HiRISE) onboard Mars Reconnaissance Orbiter (MRO) has been used to monitor the seasonal evolution of several regions at high southern latitudes. Of particular interest have been jet-like activities that may result from the process described by Kieffer (2007), involving translucent CO2 ice. These jets are assumed to create fan-shaped ground features, as studied e.g. in Hansen et.al. (2010) and Portyankina et.al. (2010). In Thomas et.al. (2009), a small region of interest (ROI) inside the south polar Inca City region (81° S, 296° E) was defined for which the seasonal change of the number of fans was determined. This ROI was chosen for its strong visual variability in ground features. The mostly manual counting work showed, that the number of apparent fans increases monotonously for a considerable amount of time from the beginning of the spring time observations at Ls of 178° until approx. 230° , following the increase of available solar energy for the aforementioned processes of the Kieffer model. This fact indicates that the number of visual fan features can be used as an activity measure for the seasonal evolution of this area, in addition to commonly used evolution studies of surface reflectance. Motivated by these results, we would like to determine the fan count evolution for more south polar areas like Ithaca, Manhattan, Giza and others. To increase the reproducibility of the results by avoiding potential variability in fan shape recognition by human eye and to increase the production efficiency, efforts are being undertaken to automise the fan counting procedure. The techniques used, cleanly separated in different stages of the procedure, the difficulties for each stage and an overview of the tools used at each step will be presented. After showing a proof of concept in Aye et.al. (2010), for a ROI that is comparable to the one previously used for manual counting in Thomas et.al. (2009), we now will show

  19. Fungi occurring on forests injured by air pollutants in the Upper Silesia and Cracow industrial regions. Pt. 10. Mycoflora of dying young trees of Alnus incana

    Energy Technology Data Exchange (ETDEWEB)

    Domanski, S.; Kowalski, T.

    1987-01-01

    The results of a 10-year study on the mortality of Alnus incana in the Upper Silesia industrial region (Poland) are presented in this paper. Fungi which infected the trees at different stages of the disease were identified. The most common were: Cryptosphora suffusa, Hypoxylon fuscum, Peniophora cinerea, P. erikssonii, Pezicula cinnamomea, Tymipanis alnea, and Valsa diatrypa.

  20. Practices and constraints in Bambara Groundnut’s production, marketing and consumption in the Brong Ahafo and Upper East Regions of Ghana

    NARCIS (Netherlands)

    Berchie, J.N.; Adu-Dapaah, H.K.; Dankyi, A.A.; Plahar, W.A.; Nelson-Quartey, F.; Haleegoah, J.

    2010-01-01

    A study was undertaken to understand the practices and major constraints in bambara groundnut production, marketing and consumption in the Brong Ahafo (Transition) and Upper East (Guinea Savannah) Regions of Ghana. A total of 200 bambara producers, 33 marketers and 68 consumers were randomly chosen

  1. An unusual giant spiral arc in the polar cap region during the northward phase of a Coronal Mass Ejection

    Directory of Open Access Journals (Sweden)

    L. Rosenqvist

    2007-03-01

    Full Text Available The shock arrival of an Interplanetary Coronal Mass Ejection (ICME at ~09:50 UT on 22 November 1997 resulted in the development of an intense (Dst<−100 nT geomagnetic storm at Earth. In the early, quiet phase of the storm, in the sheath region of the ICME, an unusual large spiral structure (diameter of ~1000 km was observed at very high latitudes by the Polar UVI instrument. The evolution of this structure started as a polewardly displaced auroral bulge which further developed into the spiral structure spreading across a large part of the polar cap. This study attempts to examine the cause of the chain of events that resulted in the giant auroral spiral. During this period the interplanetary magnetic field (IMF was dominantly northward (Bz>25 nT with a strong duskward component (By>15 nT resulting in a highly twisted tail plasma sheet. Geotail was located at the equatorial dawnside magnetotail flank and observed accelerated plasma flows exceeding the solar wind bulk velocity by almost 60%. These flows are observed on the magnetosheath side of the magnetopause and the acceleration mechanism is proposed to be typical for strongly northward IMF. Identified candidates to the cause of the spiral structure include a By induced twisted magnetotail configuration, the development of magnetopause surface waves due to the enhanced pressure related to the accelerated magnetosheath flows aswell as the formation of additional magnetopause deformations due to external solar wind pressure changes. The uniqeness of the event indicate that most probably a combination of the above effects resulted in a very extreme tail topology. However, the data coverage is insufficient to fully investigate the physical mechanism behind the observations.

  2. Determining the source region of auroral emissions in the prenoon oval using coordinated Polar BEAR UV-imaging and DMSP particle measurements

    International Nuclear Information System (INIS)

    Newell, P.T.; Meng, C.I.; Huffman, R.E.

    1992-01-01

    The Polar Beacon Experiment and Auroral Research (Polar BEAR) satellite included the capability for imaging the dayside auroral oval in full sunlight at several wavelengths. The authors compare particle observations from the DMSP F7 satellite during dayside auroral oval crossings with approximately simultaneous Polar BEAR 1,356-angstrom images to determine the magnetospheric source region of the dayside auroral oval. The source region is determined from the Defense Meteorological Satellite Program (DMSP) particle data, according to recent work concerning the classification and identification of precipitation source regions. The close DMSP/Polar BEAR coincidences all occur when the former satellite is located between 0945 and 1,000 MLT. The authors found instances of auroral arcs mapping to each of several different regions, including the boundary plasma sheet, the low-latitude boundary layer, and the plasma mantle. However, the results indicate that about half the time the most prominent auroral arcs are located at the interfaces between distinct plasma regions, at least at the local time studied here

  3. Surface temperatures in the polar regions from Nimbus 7 temperature humidity infrared radiometer

    Science.gov (United States)

    Comiso, Josefino C.

    1994-01-01

    Monthly surface temperatures in the Arctic and Antarctic regions have been derived from the 11.5 micrometer thermal infrared channel of the Nimbus 7 temperature humidity infrared radiometer (THIR) for a whole year in 1979 and for a winter and a summer month from 1980 through 1985. The data set shows interannual variability and provides spatial details that allow identification of temperature patterns over sea ice and ice sheet surfaces. For example, the coldest spot in the southern hemisphere is observed to be consistently in the Antarctic plateau in the southern hemisphere, while that in the northern hemisphere is usually located in Greenland, or one of three other general areas: Siberia, the central Arctic, or the Canadian Archipelago. Also, in the southern hemisphere, the amplitude of the seasonal fluctuation of ice sheet temperatures is about 3 times that of sea ice, while in the northern hemisphere, the corresponding fluctuations for the two surfaces are about the same. The main sources of error in the retrieval are cloud and other atmospheric effects. These were minimized by first choosing the highest radiance value from the set of measurements during the day taken within a 30 km by 30 km grid of each daily map. Then the difference of daily maps was taken and where the difference is greater than a certain threshold (which in this case is 12 C), the data element is deleted. Overall, the monthly maps derived from the resulting daily maps are spatially and temporally consistent, are coherent with the topograph y of the Antarctic continent and the location of the sea ice edge, and are in qualitative agreement with climatological data. Quantitatively, THIR data are in good agreement with Antarctic ice sheet surface air temperature station data with a correlation coefficient of 0.997 and a standard deviation of 2.0 C. The absolute values are not as good over the sea ice edges, but a comparison with Russian 2-m drift station temperatures shows very high correlation

  4. Land cover in Upper Egypt assessed using regional and global land cover products derived from MODIS imagery.

    Science.gov (United States)

    Fuller, Douglas O; Parenti, Michael S; Gad, Adel M; Beier, John C

    2012-01-01

    Irrigation along the Nile River has resulted in dramatic changes in the biophysical environment of Upper Egypt. In this study we used a combination of MODIS 250 m NDVI data and Landsat imagery to identify areas that changed from 2001-2008 as a result of irrigation and water-level fluctuations in the Nile River and nearby water bodies. We used two different methods of time series analysis -- principal components (PCA) and harmonic decomposition (HD), applied to the MODIS 250 m NDVI images to derive simple three-class land cover maps and then assessed their accuracy using a set of reference polygons derived from 30 m Landsat 5 and 7 imagery. We analyzed our MODIS 250 m maps against a new MODIS global land cover product (MOD12Q1 collection 5) to assess whether regionally specific mapping approaches are superior to a standard global product. Results showed that the accuracy of the PCA-based product was greater than the accuracy of either the HD or MOD12Q1 products for the years 2001, 2003, and 2008. However, the accuracy of the PCA product was only slightly better than the MOD12Q1 for 2001 and 2003. Overall, the results suggest that our PCA-based approach produces a high level of user and producer accuracies, although the MOD12Q1 product also showed consistently high accuracy. Overlay of 2001-2008 PCA-based maps showed a net increase of 12 129 ha of irrigated vegetation, with the largest increase found from 2006-2008 around the Districts of Edfu and Kom Ombo. This result was unexpected in light of ambitious government plans to develop 336 000 ha of irrigated agriculture around the Toshka Lakes.

  5. Productivity of Stored Water in Some Selected Multiple Use Small Reservoirs in the Upper East Region of Ghana

    Science.gov (United States)

    Annor, F. O.; Yamoah-Antwi, D.; Odai, S. N.; Adjei, K. A.; van de Giesen, N. C.

    2009-04-01

    The Upper East Region (UER) of Ghana is a water stressed area with agriculture as the main occupation of the inhabitants. The importance of small reservoirs for the sustenance of the livelihood of the people in this part of the country during the dry season cannot be over emphasized. Most of these small reservoirs were constructed, in the 1960s, mainly with the aim of providing water for domestic use and livestock watering during the dry periods of the year. Over the years, however, these small reservoirs have been put to a variety of uses, some of which accelerate the depletion of the stored water. The reservoirs are therefore most times, unable to serve the purposes for which they were constructed. To address this situation, a study was conducted to determine the productivity of stored water in small reservoirs to better inform policy makers and water managers in the allocation of water especially in the dry season. Water productivity can be thought of as the output (product) that can be obtained per unit volume of water used or applied for either crop or livestock production. Data on crops and livestock were obtained through questionnaire administration, interviews, focus group discussions, physical measurements as well as field observations from nine reservoirs in the UER. The research findings show that donkeys have the highest productivity of about US90 followed by cattle with US70. These high productivity values are as a result of the variety of products and services rendered by donkeys and cattle. For crop, tomatoes have the highest productivity value compared with pepper and leafy vegetables. Despite the fact that donkeys had the highest productivity and hence priority over all uses, it is prudent to note that, inhabitants of the study area aside the sale of livestock for money (income) keep livestock for prestige. Therefore in the allocation of stored water in small multiple use reservoirs, the allocation criteria should consider the views, values and

  6. Identification of fish nursery areas in a free tributary of an impoundment region, upper Uruguay River, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Alves da Silva

    Full Text Available This study aims to determine the importance of different environments of the Ligeiro River (upper Uruguay River, Brazil in fish reproduction. For this purpose, three environments (sampling sites were selected: rapids, a pool, and the mouth of the Ligeiro River. Ichthyoplankton, zooplankton, and benthos were sampled six times per month from September, 2006 to March, 2007. Zooplankton and ichthyoplankton samples were collected early in the evening with plankton nets (64 µm and 500 µm, respectively. Benthos samples were also collected early in the evening with a Van Veen dredge. Local abiotic variables (temperature, dissolved oxygen, pH, electrical conductivity, water speed, alkalinity, water hardness, and water transparency were measured simultaneously with the biotic data sampling and were complemented by regional variables (water flow and precipitation. A total of 43,475 eggs and 2,269 larvae were captured. Of these larvae, 80.1% were in the pre-flexion and larval yolk stages. Digestive tract content showed that the greatest degree of repletion among the larvae in more advanced phases occurred in the pool environment. Water speed was the main characteristic used to differentiate the river's rapids and mouth from the pool. The abundance of zooplankton and benthos was not related to the distribution of densities among the different components of the ichthyoplankton. A greater abundance of eggs and larvae with yolk was found in the rapids and river mouth. Ordination analyses showed a connection between the advanced stage larvae and the pool environment. In conclusion, the rapids and river mouth of the Ligeiro River's are important locations for fish reproduction, particularly in regard to spawning and drifting of the ichthyoplankton's initial stages, whereas the pool represents a nursery place for larval growth.

  7. Hydrothermal dolomitization of the Bekhme formation (Upper Cretaceous), Zagros Basin, Kurdistan Region of Iraq: Record of oil migration and degradation

    Science.gov (United States)

    Mansurbeg, Howri; Morad, Daniel; Othman, Rushdy; Morad, Sadoon; Ceriani, Andrea; Al-Aasm, Ihsan; Kolo, Kamal; Spirov, Pavel; Proust, Jean Noel; Preat, Alain; Koyi, Hemin

    2016-07-01

    The common presence of oil seepages in dolostones is widespread in Cretaceous carbonate successions of the Kurdistan Region of Iraq. This integrated field, petrographic, chemical, stable C, O and Sr isotopes, and fluid inclusion study aims to link dolomitization to the origin and geochemical evolution of fluids and oil migration in the Upper Cretaceous Bekhme carbonates. Flux of hot basinal (hydrothermal) brines, which is suggested to have occurred during the Zagros Orogeny, resulted in dolomitization and cementation of vugs and fractures by coarse-crystalline saddle dolomite, equant calcite and anhydrite. The saddle dolomite and host dolostones have similar stable isotopic composition and formed prior to oil migration from hot (81-115 °C) basinal NaCl-MgCl2-H2O brines with salinities of 18-22 wt.% NaCl eq. The equant calcite cement, which surrounds and hence postdates saddle dolomite, has precipitated during oil migration from cooler (60-110 °C) NaCl-CaCl2-H2O brines (14-18 wt.% NaCl eq). The yellowish fluorescence color of oil inclusions in the equant calcite indicates that the oil had API gravity of 15-25° composition, which is lighter than present-day oil in the reservoirs (API of 10-17°). This difference in oil composition is attributed to oil degradation by the flux of meteoric water, which is evidenced by the low δ13C values (- 8.5‰ to - 3.9‰ VPDB) as well as by nil salinity and low temperature in fluid inclusions of late columnar calcite cement. This study demonstrates that linking fluid flux history and related diagenesis to the tectonic evolution of the basin provides important clues to the timing of oil migration, degradation and reservoir evolution.

  8. Investigation of Temperature Dynamics in Small and Shallow Reservoirs, Case Study: Lake Binaba, Upper East Region of Ghana

    Directory of Open Access Journals (Sweden)

    Ali Abbasi

    2016-03-01

    Full Text Available An unsteady fully three-dimensional model of Lake Binaba (a shallow small reservoir in semi-arid Upper East Region of Ghana has been developed to simulate its temperature dynamics. The model developed is built on the Reynolds Averaged Navier–Stokes (RANS equations, utilizing the Boussinesq approach. As the results of the model are significantly affected by the physical conditions on the boundaries, allocating appropriate boundary conditions, particularly over a water surface, is essential in simulating the lake’s thermal structure. The thermal effects of incoming short-wave radiation implemented as a heat source term in the temperature equation, while the heat fluxes at the free water surface, which depend on wind speed, air temperature, and atmospheric stability conditions are considered as temperature boundary condition. The model equations were solved using OpenFOAM CFD toolbox. As the flow is completely turbulent, which is affected by the complex boundary conditions, a new heat transfer solver and turbulence model were developed to investigate the spatial and temporal distribution of temperature in small and shallow inland water bodies using improved time-dependent boundary conditions. The computed temperature values were compared with four days of observed field data. Simulated and observed temperature profiles show reasonable agreement where the root mean square error (RMSE over the simulation period ranges from 0.11 to 0.44 °C in temporal temperature profiles with an average value of 0.33 °C. Results indicate that the model is able to simulate the flow variables and the temperature distribution in small inland water bodies with complex bathymetry.

  9. Parameterization of the middle and upper tropospheric water vapor from ATOVS observations over a tropical climate region

    Science.gov (United States)

    Makama, Ezekiel Kaura; Lim, Hwee San; Abdullah, Khiruddin

    2018-01-01

    Precipitable water vapor (PWV) is a highly variable, but important greenhouse gas that regulates the radiation budget of the earth. Its variability in time and space makes it difficult to quantify. Knowledge of its vertical distribution, in particular, is crucial for many reasons. In this study, empirical relationships between isobaric layers of PWV over Peninsular Malaysia are examined. Analysis of variance (ANOVA) technique on Advanced Television and Infrared Observation Satellite Operational Vertical Sounder (ATOVS) observations, from 2005 to 2011, has been used to propose a relationship of the form, W=α(WL)β for the middle (MW) and upper (UW) layers PWV. W is either MW or UW with α and β as regression coefficients, which are functions of latitude. Coefficients of determination (R2) and root mean square error (RMSE) of respective values between 0.75-0.86 and 1.65-2.38 mm, across the zones, were obtained for both the MW and UW predictions, with a mean bias (MB) below ±1 mm.The predicted and observed PWV presented a better agreement northerly. Initial predictability test for each model was done on two independent data sets: ATOVS (2012-2015), and radiosonde (2010-2011) at Penang, Kuantan and Sepang stations, with very good outcomes. The results of the tests revealed remarkable performances, when compared with two previously reported models. The inclusion of variable regression coefficients, and the utilization of satellite-derived data, which provide soundings of data-void regions between radiosonde networks, proved to have optimized the results.

  10. Assessing the Impact of Climate Change on Land-Water-Ecosystem Quality in Polar and Mountainous Regions: A New Interregional Project (INT5153)

    Energy Technology Data Exchange (ETDEWEB)

    Dercon, Gerd [Soil and Water Management and Crop Nutrition Subprogramme, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, IAEA, Seibersdorf (Austria); Gerardo-Abaya, Jane [Division for Asia and the Pacific Section 2, Department of Technical Cooperation, IAEA, Vienna (Austria); Mavlyudov, Bulat [Institute of Geography, Russian Academy of Sciences, Moscow (Russian Federation); others, and

    2014-07-15

    The INT5153 project aims to improve the understanding of the impact of climate change on fragile polar and mountainous ecosystems on both a local and global scale for their better management and conservation. Seven core and five related benchmark sites have been selected from different global regions for specific assessments of the impact of climate change with the following expected outcomes and outputs: Outcomes: • Improved understanding of the impact of climate change on the cryosphere in polar and mountainous ecosystems and its effects on landwater- ecosystem quality at both local and global scales. • Recommendations for improvement of regional policies for soil and agricultural water management, conservation, and environmental protection in polar and mountainous regions. Outputs: • Specific strategies to minimize the adverse effects of, and adapt to, reduced seasonal snow and glacier covered areas on land-water-ecosystem quality in polar and mountain regions across the world. • Enhanced interregional network of laboratories and institutions competent in the assessment of climate change impacts on the cryosphere and land-water-ecosystem quality, using isotopic and nuclear techniques. • Increased number of young scientists trained in the use of isotope and nuclear techniques to assess the impact of climate change on the cryosphere and land-water-ecosystem quality in polar and mountainous ecosystems. • Platform/database with global access for continuing work and monitoring of impact of climate change on fragile polar and mountainous ecosystems at local and global scales, as well as for communicating findings to policy makers and communities. • Improved understanding of the effects of climate change disseminated through appropriate publications, policy briefs, and through a dedicated internet platform. • Methodologies and protocols for investigations in specific ecosystems and conservation/adaptation measures for agriculture areas.

  11. Assessing the Impact of Climate Change on Land-Water-Ecosystem Quality in Polar and Mountainous Regions: A New Interregional Project (INT5153)

    International Nuclear Information System (INIS)

    Dercon, Gerd; Gerardo-Abaya, Jane; Mavlyudov, Bulat

    2014-01-01

    The INT5153 project aims to improve the understanding of the impact of climate change on fragile polar and mountainous ecosystems on both a local and global scale for their better management and conservation. Seven core and five related benchmark sites have been selected from different global regions for specific assessments of the impact of climate change with the following expected outcomes and outputs: Outcomes: • Improved understanding of the impact of climate change on the cryosphere in polar and mountainous ecosystems and its effects on landwater- ecosystem quality at both local and global scales. • Recommendations for improvement of regional policies for soil and agricultural water management, conservation, and environmental protection in polar and mountainous regions. Outputs: • Specific strategies to minimize the adverse effects of, and adapt to, reduced seasonal snow and glacier covered areas on land-water-ecosystem quality in polar and mountain regions across the world. • Enhanced interregional network of laboratories and institutions competent in the assessment of climate change impacts on the cryosphere and land-water-ecosystem quality, using isotopic and nuclear techniques. • Increased number of young scientists trained in the use of isotope and nuclear techniques to assess the impact of climate change on the cryosphere and land-water-ecosystem quality in polar and mountainous ecosystems. • Platform/database with global access for continuing work and monitoring of impact of climate change on fragile polar and mountainous ecosystems at local and global scales, as well as for communicating findings to policy makers and communities. • Improved understanding of the effects of climate change disseminated through appropriate publications, policy briefs, and through a dedicated internet platform. • Methodologies and protocols for investigations in specific ecosystems and conservation/adaptation measures for agriculture areas

  12. A P-wave velocity model of the upper crust of the Sannio region (Southern Apennines, Italy

    Directory of Open Access Journals (Sweden)

    M. Cocco

    1998-06-01

    Full Text Available This paper describes the results of a seismic refraction profile conducted in October 1992 in the Sannio region, Southern Italy, to obtain a detailed P-wave velocity model of the upper crust. The profile, 75 km long, extended parallel to the Apenninic chain in a region frequently damaged in historical time by strong earthquakes. Six shots were fired at five sites and recorded by a number of seismic stations ranging from 41 to 71 with a spacing of 1-2 km along the recording line. We used a two-dimensional raytracing technique to model travel times and amplitudes of first and second arrivals. The obtained P-wave velocity model has a shallow structure with strong lateral variations in the southern portion of the profile. Near surface sediments of the Tertiary age are characterized by seismic velocities in the 3.0-4.1 km/s range. In the northern part of the profile these deposits overlie a layer with a velocity of 4.8 km/s that has been interpreted as a Mesozoic sedimentary succession. A high velocity body, corresponding to the limestones of the Western Carbonate Platform with a velocity of 6 km/s, characterizes the southernmost part of the profile at shallow depths. At a depth of about 4 km the model becomes laterally homogeneous showing a continuous layer with a thickness in the 3-4 km range and a velocity of 6 km/s corresponding to the Meso-Cenozoic limestone succession of the Apulia Carbonate Platform. This platform appears to be layered, as indicated by an increase in seismic velocity from 6 to 6.7 km/s at depths in the 6-8 km range, that has been interpreted as a lithological transition from limestones to Triassic dolomites and anhydrites of the Burano formation. A lower P-wave velocity of about 5.0-5.5 km/s is hypothesized at the bottom of the Apulia Platform at depths ranging from 10 km down to 12.5 km; these low velocities could be related to Permo-Triassic siliciclastic deposits of the Verrucano sequence drilled at the bottom of the Apulia

  13. A vertical hydroclimatology of the Upper Indus Basin and initial insights to potential hydrological change in the region

    Science.gov (United States)

    Forsythe, Nathan; Kilsby, Chris G.; Fowler, Hayley J.; Archer, David R.

    2010-05-01

    The water resources of the Upper Indus Basin (UIB) are of the utmost importance to the economic wellbeing of Pakistan. The irrigated agriculture made possible by Indus river runoff underpins the food security for Pakistan's nearly 200 million people. Contributions from hydropower account for more than one fifth of peak installed electrical generating capacity in a country where widespread, prolonged load-shedding handicaps business activity and industrial development. Pakistan's further socio-economic development thus depends largely on optimisation of its precious water resources. Confident, accurate projections of future water resource availability and variability are urgent insights needed by development planners and infrastructure managers at all levels. Correctly projecting future hydrological conditions depends first and foremost on a thorough understanding of the underlying mechanisms and processes of present hydroclimatology. The vertical and horizontal spatial variations in key climate parameters (temperature, precipitation) govern the contributions of the various elevation zones and subcatchments comprising the UIB. Trends in this complex mountainous region are highly varied by season and parameter. Observed changes here often do not match general global trends or even necessarily those found in neighbouring regions. This study considers data from a variety sources in order to compose the most complete picture possible of the vertical hydroclimatology of the UIB. The study presents the observed climatology and trends for precipitation and temperature from local observations at long-record meteorological stations (Pakistan Meteorological Department). These data are compared to characterisations of additional water cycle parameters (humidity, cloud, snow cover and snow-water-equivalent) derived from local short-record automatic weather stations, the ECMWF ‘ERA' reanalysis projects and satellite based observations (AVHRR, MODIS, etc). The potential

  14. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON RHIC SPIN PHYSICS III AND IV, POLARIZED PARTONS AT HIGH Q2 REGION (VOLUME 31)

    International Nuclear Information System (INIS)

    BUNCE, G.; VIGDOR, S.

    2001-01-01

    International workshop on II Polarized Partons at High Q2 region 11 was held at the Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, Japan on October 13-14, 2000, as a satellite of the international conference ''SPIN 2000'' (Osaka, Japan, October 16-21,2000). This workshop was supported by RIKEN (The Institute of Physical and Chemical Research) and by Yukawa Institute. The scientific program was focused on the upcoming polarized collider RHIC. The workshop was also an annual meeting of RHIC Spin Collaboration (RSC). The number of participants was 55, including 28 foreign visitors and 8 foreign-resident Japanese participants, reflecting the international nature of the RHIC spin program. At the workshop there were 25 oral presentations in four sessions, (1) RHIC Spin Commissioning, (2) Polarized Partons, Present and Future, (3) New Ideas on Polarization Phenomena, (4) Strategy for the Coming Spin Running. In (1) the successful polarized proton commissioning and the readiness of the accelerator for the physics program impressed us. In (2) and (3) active discussions were made on the new structure function to be firstly measured at RHIC, and several new theoretical ideas were presented. In session (4) we have established a plan for the beam time requirement toward the first collision of polarized protons. These proceedings include the transparencies presented at the workshop. The discussion on ''Strategy for the Coming Spin Running'' was summarized by the chairman of the session, S. Vigdor and G. Bunce

  15. A brief report on the statistical study of net electric current in solar active regions with longitudinal fields of opposite polarity

    International Nuclear Information System (INIS)

    Gao Yu

    2013-01-01

    Dynamic processes occurring in solar active regions are dominated by the solar magnetic field. As of now, observations using a solar magnetograph have supplied us with the vector components of a solar photospheric magnetic field. The two transverse components of a photospheric magnetic field allow us to compute the amount of electric current. We found that the electric current in areas with positive (negative) polarity due to the longitudinal magnetic field have both positive and negative signs in an active region, however, the net current is found to be an order-of-magnitude less than the mean absolute magnitude and has a preferred sign. In particular, we have statistically found that there is a systematic net electric current from areas with negative (positive) polarity to areas with positive (negative) polarity in solar active regions in the northern (southern) hemisphere, but during the solar minimum this tendency is reversed over time at some latitudes. The result indicates that there is weak net electric current in areas of solar active regions with opposite polarity, thus providing further details about the hemispheric helicity rule found in a series of previous studies.

  16. Polarization of the microwave background in open universes

    International Nuclear Information System (INIS)

    Tolman, B.W.

    1985-01-01

    The polarization and anisotropy of the microwave background radiation in open universes with an expansion anisotropy, arising from either cosmological anisotropy or density inhomogeneities on large scales, are computed by a direct, or Monte Carlo, simulation of the problem. The simulation includes accurate numerical data for the ionization of matter during both the decoupling and the reheated eras. Besides the well-known result that the radiation anisotropy is distorted and focused by the spatial curvature into a single very small, intense spot, it is found that the scattering of this spot during the reheated epoch generates features in the polarization of the radiation which cover fully one-half of the sky. The radiation is polarized in a wide band encircling the spot, with the direction of polarization opposite that of the rest of the sky and at a level only slightly below present observed upper limits, given an expansion anisotropy also near its upper limit. This region of strong polarization is surrounded by an unpolarized band near the equator (where the spot is at a pole), while the rest of the sky is also polarized at a level near the upper limits. The amount of polarization is very sensitive to the amount of scattering, and thus to the reheating epoch; further, features in the polarization remain visible even for very long reheated epochs, whereas the intensity anisotropy is quickly damped out. The widths of the unusually polarized region and the spot are sensitive to the cosmological matter density. The extension of these results to the case of a spectrum of large-scale inhomogeneities is briefly discussed. The polarization of the microwaves thus provides an important and observationally accessible test of these cosmological models

  17. A study for a guide chart of lower and upper boundary regions to avoid the condensation-induced water hammer in a long horizontal pipe

    International Nuclear Information System (INIS)

    Lee, Byung Jin

    1995-02-01

    Effects of the key system parameters such as the pipe length, the pipe diameter, the feedwater temperature and the system pressure on the critical flow rates of both the upper and the lower boundaries have been examined for long horizontal pipes. The upper and lower critical flow rates are sensitive to the pipe diameter, the pipe length and the system pressure, but not to the feedwater temperature over the practical operating ranges. Guide charts of the CIWH region boundary have been developed to be used in the system design and operation to predict the operating conditions vulnerable to the CIWH. The charts illustrate a series of the operating ranges bounded by the lower and the upper limiting curves where the water hammer is very likely to occur. A design and operational procedure has also been provided to help the designer and the operator to avoid the CIWH

  18. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars

    Science.gov (United States)

    Ewing, Ryan C.; Peyret, Aymeric-Pierre B.; Kocurek, Gary; Bourke, Mary

    2010-08-01

    High-Resolution Imaging Science Experiment (HiRISE) imagery of the central Olympia Undae Dune Field in the north polar region of Mars shows a reticulate dune pattern consisting of two sets of nearly orthogonal dune crestlines, with apparent slipfaces on the primary crests, ubiquitous wind ripples, areas of coarse-grained wind ripples, and deflated interdune areas. Geomorphic evidence and dune field pattern analysis of dune crest length, spacing, defect density, and orientation indicates that the pattern is complex, representing two constructional generations of dunes. The oldest and best-organized generation forms the primary crestlines and is transverse to circumpolar easterly winds. Gross bed form-normal analysis of the younger pattern of crestlines indicates that it emerged with both circumpolar easterly winds and NE winds and is reworking the older pattern. Mapping of secondary flow fields over the dunes indicates that the most recent transporting winds were from the NE. The younger pattern appears to represent an influx of sediment to the dune field associated with the development of the Olympia Cavi reentrant, with NE katabatic winds channeling through the reentrant. A model of the pattern reformation based upon the reconstructed primary winds and resulting secondary flow fields shows that the development of the secondary pattern is controlled by the boundary condition of the older dune topography.

  19. The influence of IMF cone angle on invariant latitudes of polar region footprints of FACs in the magnetotail: Cluster observatio

    Science.gov (United States)

    Cheng, Z.; Shi, J.; Zhang, J.; Kistler, L. M.

    2017-12-01

    The influence of the interplanetary magnetic field (IMF) cone angle θ (the angle between the IMF direction and the Sun-Earth line) on the invariant latitudes (ILATs) of the footprints of the field-aligned currents (FACs) in the magnetotail has been investigated. We performed a statistic study of 542 FAC cases observed by the four Cluster spacecraft in the northern hemisphere. The results show that the large FAC (>10 nA/m2) cases occur at the low ILATs (60º, which implies the footprints of the large FACs mainly expand equatorward with large IMF cone angle. The equatorward boundary of the FAC footprints in the polar region decreases with the IMF cone angle especially when IMF Bz is positive. There is almost no correlation or a weak positive correlation of the poleward boundary and IMF cone angle no matter IMF is northward or southward. The equatorward boundary is more responsive to the IMF cone angle. Compared to the equatorward boundary, the center of the FAC projected location changes very little. This is the first time a correlation between FAC projected location and IMF cone angle has been determined.

  20. A polar-region-adaptable systematic bias collaborative measurement method for shipboard redundant rotational inertial navigation systems

    Science.gov (United States)

    Wang, Lin; Wu, Wenqi; Wei, Guo; Lian, Junxiang; Yu, Ruihang

    2018-05-01

    The shipboard redundant rotational inertial navigation system (RINS) configuration, including a dual-axis RINS and a single-axis RINS, can satisfy the demand of marine INSs of especially high reliability as well as achieving trade-off between position accuracy and cost. Generally, the dual-axis RINS is the master INS, and the single-axis RINS is the hot backup INS for high reliability purposes. An integrity monitoring system performs a fault detection function to ensure sailing safety. However, improving the accuracy of the backup INS in case of master INS failure has not been given enough attention. Without the aid of any external information, a systematic bias collaborative measurement method based on an augmented Kalman filter is proposed for the redundant RINSs. Estimates of inertial sensor biases can be used by the built-in integrity monitoring system to monitor the RINS running condition. On the other hand, a position error prediction model is designed for the single-axis RINS to estimate the systematic error caused by its azimuth gyro bias. After position error compensation, the position information provided by the single-axis RINS still remains highly accurate, even if the integrity monitoring system detects a dual-axis RINS fault. Moreover, use of a grid frame as a navigation frame makes the proposed method applicable in any area, including the polar regions. Semi-physical simulation and experiments including sea trials verify the validity of the method.

  1. Regional hardening of Upper Cretaceous Chalk in eastern England, UK: trace element and stable isotope patterns in the Upper Cenomanian and Turonian Chalk and their significance

    Science.gov (United States)

    Jeans, Christopher V.; Long, Dee; Hu, Xiu-Fang; Mortimore, Rory N.

    2014-12-01

    The regional hardening of the Late Cenomanian to Early Turonian Chalk of the Northern Province of eastern England has been investigated by examining the pattern of trace elements and stable carbon and oxygen isotopes in the bulk calcite of two extensive and stratigraphically adjacent units each 4 to 5 m thick of hard chalk in Lincolnshire and Yorkshire. These units are separated by a sequence, 0.3-1.3 m thick, of variegated marls and clayey marls. Modelling of the geochemistry of the hard chalk by comparison with the Standard Louth Chalk, combined with associated petrographic and geological evidence, indicates that (1) the hardening is due to the precipitation of a calcite cement, and (2) the regional and stratigraphical patterns of geochemical variation in the cement are largely independent of each other and have been maintained by the impermeable nature of the thin sequence of the clay-rich marls that separate them. Two phases of calcite cementation are recognised. The first phase was microbially influenced and did not lithify the chalk. It took place predominantly in oxic and suboxic conditions under considerable overpressure in which the Chalk pore fluids circulated within the units, driven by variations in compaction, temperature, pore fluid pressure and local tectonics. There is evidence in central and southern Lincolnshire of the loss of Sr and Mgenriched pore fluids to the south during an early part of this phase. The second phase of calcite precipitation was associated with the loss of overpressure in probably Late Cretaceous and in Cenozoic times as the result of fault movement in the basement penetrating the overlying Chalk and damaging the seal between the two chalk units. This greatly enhanced grain pressures, resulting in grain welding and pressure dissolution, causing lithification with the development of stylolites, marl seams, and brittle fractures. Associated with this loss of overpressure was the penetration of the chalk units by allochthonous

  2. Constraining controls on carbonate sequences with high-resolution chronostratigraphy: Upper Miocene, Cabo de Gata region, SE Spain

    Science.gov (United States)

    Montgomery, P.; Farr, M.R.; Franseen, E.K.; Goldstein, R.H.

    2001-01-01

    A high-resolution chronostratigraphy has been developed for Miocene shallow-water carbonate strata in the Cabo de Gata region of SE Spain for evaluation of local, regional and global factors that controlled platform architecture prior to and during the Messinian salinity crisis. Paleomagnetic data were collected from strata at three localities. Mean natural remanent magnetization (NRM) ranges between 1.53 ?? 10-8 and 5.2 ?? 10-3 Am2/kg. Incremental thermal and alternating field demagnetization isolated the characteristic remanent magnetization (ChRM). Rock magnetic studies show that the dominant magnetic mineral is magnetite, but mixtures of magnetite and hematite occur. A composite chronostratigraphy was derived from five stratigraphic sections. Regional stratigraphic data, biostratigraphic data, and an 40Ar/39Ar date of 8.5 ?? 0.1 Ma, for an interbedded volcanic flow, place the strata in geomagnetic polarity Chrons C4r to C3r. Sequence-stratigraphic and diagenetic evidence indicate a major unconformity at the base of depositional sequence (DS)3 that contains a prograding reef complex, suggesting that approximately 250 000 yr of record (Subchrons C3Br.2r to 3Br.1r) are missing near the Messinian-Tortonian boundary. Correlation to the GPTS shows that the studied strata represent five third- to fourth-order DSs. Basal units are temperate to subtropical ramps (DS1A, DS1B, DS2); these are overlain by subtropical to tropical reefal platforms (DS3), which are capped by subtropical to tropical cyclic carbonates (Terminal Carbonate Complex, TCC). Correlation of the Cabo de Gata record to the Melilla area of Morocco, and the Sorbas basin of Spain indicate that early - Late Tortonian ramp strata from these areas are partially time-equivalent. Similar strata are extensively developed in the Western Mediterranean and likely were influenced by a cool climate or influx of nutrients during an overall rise in global sea-level. After ramp deposition, a sequence boundary (SB3) in

  3. Early optical polarization of a gamma-ray burst afterglow.

    Science.gov (United States)

    Mundell, Carole G; Steele, Iain A; Smith, Robert J; Kobayashi, Shiho; Melandri, Andrea; Guidorzi, Cristiano; Gomboc, Andreja; Mottram, Chris J; Clarke, David; Monfardini, Alessandro; Carter, David; Bersier, David

    2007-03-30

    We report the optical polarization of a gamma-ray burst (GRB) afterglow, obtained 203 seconds after the initial burst of gamma-rays from GRB 060418, using a ring polarimeter on the robotic Liverpool Telescope. Our robust (2sigma) upper limit on the percentage of polarization, less than 8%, coincides with the fireball deceleration time at the onset of the afterglow. The combination of the rate of decay of the optical brightness and the low polarization at this critical time constrains standard models of GRB ejecta, ruling out the presence of a large-scale ordered magnetic field in the emitting region.

  4. Polarized BRDF measurement of steel E235B in the near-infrared region: Based on a self-designed instrument with absolute measuring method

    Science.gov (United States)

    Liu, Yanlei; Yu, Kun; Liu, Zilong; Zhao, Yuejin; Liu, Yufang

    2018-06-01

    The spectral bidirectional reflectance distribution (BRDF) offers a complete description of the optical properties of the opaque material. Numerous studies on BRDF have been conducted for its important role in scientific research and industrial production. However, most of these studies focus on the visible region and unpolarized BRDF, and the spectral polarized BRDF in the near-infrared region is rarely reported. In this letter, we propose an absolute method to measure the spectral BRDF in the near-infrared region, and the detailed derivation is presented. A self-designed instrument is set up for the absolute measurement of BRDF. The reliability of this method is verified by comparing the experimental data of the three metal (aluminum, silver and gold) mirrors with the reference data. The in-plane polarized BRDF of steel E235B are measured, and the influence of incident angle and roughness on the BRDF are discussed. The degree of linear polarization (DOLP) are determined based on the polarized BRDF. The results indicate that both the roughness and incident angle have distinct influence on the BRDF and DOLP.

  5. Comparison of sediment pollution in the rivers of the Hungarian Upper Tisza Region using non-destructive analytical techniques

    International Nuclear Information System (INIS)

    Osan, Janos; Toeroek, Szabina; Alfoeldy, Balint; Alsecz, Anita; Falkenberg, Gerald; Baik, Soo Yeun; Van Grieken, Rene

    2007-01-01

    The rivers in the Hungarian Upper Tisza Region are frequently polluted mainly due to mining activities in the catchment area. At the beginning of 2000, two major mining accidents occurred in the Romanian part of the catchment area due to the failure of a tailings dam releasing huge amounts of cyanide and heavy metals to the rivers. Surface sediment as well as water samples were collected at six sites in the years 2000-2003, from the northeast-Hungarian section of the Tisza, Szamos and Tur rivers. The sediment pollution of the rivers was compared based on measurements of bulk material and selected single particles, in order to relate the observed compositions and chemical states of metals to the possible sources and weathering of pollution. Non-destructive X-ray analytical methods were applied in order to obtain different kinds of information from the same samples or particles. In order to identify the pollution sources, their magnitude and fate, complementary analyses were carried out. Heterogeneous particulate samples were analyzed from a large geographical territory and a 4-year time period. Individual particles were analyzed only from the 'hot' samples that showed elevated concentrations of heavy metals. Particles that were classified as anthropogenic were finally analyzed to identify trace concentrations and chemical states of heavy metals. Although the Tisza river was affected by water pollution due to the two major mining accidents at the beginning of 2000, the concentration of heavy metals in sediments decreased to the mineral background level 1 year after the pollution event. In the tributaries Szamos and Tur, however, no significant decrease of the heavy metal concentrations was observed in the recent years, indicating a continuous pollution. Among the water suspended particles collected from river Tur, fibers of unknown origin were observed by electron microscopy; these particles were aluminosilicates enriched in Zn and Mn. Cd was also concentrated in

  6. Indoor radon measurement in some adobe houses in the Kassena Nankana area of the Upper East Region

    International Nuclear Information System (INIS)

    Quashie, F. K.

    2010-06-01

    Inhalation of radon and its daughter products is the major contributor to the total exposure of the population to natural radiation. The present study has measured radon gas concentration in some Adobe houses and the soil radon gas around these houses in the Kassena Nankana Area of the Upper East Region by using passive radon indoor dosimeter containing solid-state nuclear track detector (SSNTD) commercially known as LR - 115 (type II, pelliculable). Fifty (50) indoor radon dosimeters were placed in the various Adobe houses in the study area. Additionally, thirty (30) dosimeters were placed in the soil around some of the houses at a depth of 75 cm. Soil radon dosimeters were retrieved after two (2) weeks while the indoor radon dosimeters were retrieved after 78 to 82 days. The detectors were then chemically etched. The digital laser optic system and the spark counter coupled with microfiche reader were used in counting both the indoor and soil detectors respectively. Indoor radon concentration in the study area range from 35.28 Bq/m 3 to 244.22 Bq/m 3 . An active dosimeter known as the radon scout plus which gives instantaneous readings between 1 to 3 hours was also used in nineteen of the adobe houses in the study area and a total average radon concentration of 56.90 Bq/m3 was obtained. The soil radon concentration was also found to range from 2.12 kBq/m 3 to 15.03 kBq/m 3 . A good correlation was found to exist between the soil radon concentration and that of the indoor radon concentration with a correlation coefficient of about 0.61. The mean radon emanation coefficient of some fifteen (15) soil samples monitored was 0.46. The average annual effective dose was estimated to be about 1.66 mSv/y and that of the average annual effective dose using the equilibrium equivalent factor (F) was 1.00 mSv/y

  7. 40Ar/39Ar dates in the Central Cordillera of Colombia: Evidence for an upper triassic regional tecnomagmatic event

    International Nuclear Information System (INIS)

    Vinasco, C.J.; Cordani, U.G.; Vasconcelos, P

    2001-01-01

    The Coastal, Western, Central and the Eastern Cordilleras constitute four independent mountain ranges in the Northern Andes. The Coastal and Western Cordillera comprises allochthonous oceanic sequences of basic volcanic rocks and marine sediments of Cenozoic and Upper Cretaceous age (Aspden et al., 1987). The so-called Central Cordillera Polymetamorphic Complex (Restrepo and Toussaint, 1982), made up the pre-Mesozoic Central Cordillera basement, consists of low through high-grade metamorphic rocks intruded by Meso-Cenozoic batholiths. The Eastern Cordillera is a polydeformed continental mountain range consisting of Precambrian and Paleozoic metamorphic and igneous rocks overlain by Paleozoic to Mesozoic sedimentary covers. The northern part of the Central Cordillera has been described as a suspect terrain affected by several tectonometamorphic episodes. The most important of them have been always considered those related to the Hercynian orogeny, in Devonian and Carboniferous times, and those occurring at the beginning of the Andean Cycle in the Cretaceous (Restrepo and Toussaint, 1982). A possible Lower Paleozoic and even Precambrian age for the basement of the terrain has also been proposed. Although some indications of a Permo-Triassic event are already available, this period was not considered as of great importance for the geologic evolution of the region. The available radiometric dates in the 200-250 Ma interval, for the Central Cordillera, are as follows: 1. One K-Ar whole rock age for a Granulite of 251±21 Ma. (Restrepo et al, 1991) of the El Retiro group SE of Medellin. However, a K-Ar biotite age of 110±10 Ma. (Toussaint et al., 1978) was obtained for a migmatite rock associated with the same group. 2. A Sm/Nd garnet and whole rock age of 226±17 Ma in rocks associated to granulites, SE of Medellin, interpreted as metamorphic ages (Correa and Martins, 2001). 3. K-Ar biotite dates for the Puqui metamorphic complex, occurring north of Medellin, ranging

  8. Paleogeographic and paleo-oceanographic influences on carbon isotope signatures: Implications for global and regional correlation, Middle-Upper Jurassic of Saudi Arabia

    Science.gov (United States)

    Eltom, Hassan A.; Gonzalez, Luis A.; Hasiotis, Stephen T.; Rankey, Eugene C.; Cantrell, Dave L.

    2018-02-01

    Carbon isotope data (δ13C) can provide an essential means for refining paleogeographic and paleo-oceanographic reconstructions, and interpreting stratigraphic architecture within complex carbonate strata. Although the primary controls on global δ13C signatures of marine carbonates are well understood, understanding their latitudinal and regional variability is poor. To better constrain the nature and applications of δ13C stratigraphy, this study: 1) presents a new high-resolution δ13C stratigraphic curve from Middle to Upper Jurassic carbonates in the upper Tuwaiq Mountain, Hanifa, and lower Jubaila formations in central Saudi Arabia; 2) explores their latitudinal and regional variability; and 3) discusses their implications for stratigraphic correlations. Analysis of δ13C data identified six mappable units with distinct δ13C signatures (units 1-6) between up-dip and down-dip sections, and one unit (unit 7) that occurs only in the down-dip section of the study succession. δ13C data from the upper Tuwaiq Mountain Formation and the lower Hanifa Formation (units 1, 2), which represent Upper Callovian to Middle Oxfordian strata, and record two broad positive δ13C excursions. In the upper part of the Hanifa Formation (units 3-6, Early Oxfordian-Late Kimmeridgian), δ13C values decreased upward to unit 7, which showed a broad positive δ13C excursion. Isotopic data suggest similar δ13C trends between the southern margin of the Tethys Ocean (Arabian Plate; low latitude, represented by the study succession) and northern Tethys oceans (high latitude), despite variations in paleoclimatic, paleogeographic, and paleoceanographic conditions. Variations in the δ13C signal in this succession can be attributed to the burial of organic matter and marine circulation at the time of deposition. Our study uses δ13C signatures to provide independent data for chronostratigraphic constraints which help in stratigraphic correlations within heterogeneous carbonate successions.

  9. Evidence for Surface Water Ice in the Lunar Polar Regions Using Reflectance Measurements from the Lunar Orbiter Laser Altimeter and Temperature Measurements from the Diviner Lunar Radiometer Experiment

    Science.gov (United States)

    Fisher, Elizabeth A.; Lucey, Paul G.; Lemelin, Myriam; Greenhagen, Benjamin T.; Siegler, Matthew A.; Mazarico, Erwan; Aharonson, Oded; Williams, Jean-Pierre; Hayne, Paul O.; Neumann, Gregory A.; hide

    2017-01-01

    We find that the reflectance of the lunar surface within 5 deg of latitude of theSouth Pole increases rapidly with decreasing temperature, near approximately 110K, behavior consistent with the presence of surface water ice. The North polar region does not show this behavior, nor do South polar surfaces at latitudes more than 5 deg from the pole. This South pole reflectance anomaly persists when analysis is limited to surfaces with slopes less than 10 deg to eliminate false detection due to the brightening effect of mass wasting, and also when the very bright south polar crater Shackleton is excluded from the analysis. We also find that south polar regions of permanent shadow that have been reported to be generally brighter at 1064 nm do not show anomalous reflectance when their annual maximum surface temperatures are too high to preserve water ice. This distinction is not observed at the North Pole. The reflectance excursion on surfaces with maximum temperatures below 110K is superimposed on a general trend of increasing reflectance with decreasing maximum temperature that is present throughout the polar regions in the north and south; we attribute this trend to a temperature or illumination-dependent space weathering effect (e.g. Hemingway et al. 2015). We also find a sudden increase in reflectance with decreasing temperature superimposed on the general trend at 200K and possibly at 300K. This may indicate the presence of other volatiles such as sulfur or organics. We identified and mapped surfaces with reflectances so high as to be unlikely to be part of an ice-free population. In this south we find a similar distribution found by Hayne et al. 2015 based on UV properties. In the north a cluster of pixels near that pole may represent a limited frost exposure.

  10. Evidence for surface water ice in the lunar polar regions using reflectance measurements from the Lunar Orbiter Laser Altimeter and temperature measurements from the Diviner Lunar Radiometer Experiment

    Science.gov (United States)

    Fisher, Elizabeth A.; Lucey, Paul G.; Lemelin, Myriam; Greenhagen, Benjamin T.; Siegler, Matthew A.; Mazarico, Erwan; Aharonson, Oded; Williams, Jean-Pierre; Hayne, Paul O.; Neumann, Gregory A.; Paige, David A.; Smith, David E.; Zuber, Maria T.

    2017-08-01

    We find that the reflectance of the lunar surface within 5° of latitude of the South Pole increases rapidly with decreasing temperature, near ∼110 K, behavior consistent with the presence of surface water ice. The North polar region does not show this behavior, nor do South polar surfaces at latitudes more than 5° from the pole. This South pole reflectance anomaly persists when analysis is limited to surfaces with slopes less than 10° to eliminate false detection due to the brightening effect of mass wasting, and also when the very bright south polar crater Shackleton is excluded from the analysis. We also find that south polar regions of permanent shadow that have been reported to be generally brighter at 1064 nm do not show anomalous reflectance when their annual maximum surface temperatures are too high to preserve water ice. This distinction is not observed at the North Pole. The reflectance excursion on surfaces with maximum temperatures below 110 K is superimposed on a general trend of increasing reflectance with decreasing maximum temperature that is present throughout the polar regions in the north and south; we attribute this trend to a temperature or illumination-dependent space weathering effect (e.g. Hemingway et al., 2015). We also find a sudden increase in reflectance with decreasing temperature superimposed on the general trend at 200 K and possibly at 300 K. This may indicate the presence of other volatiles such as sulfur or organics. We identified and mapped surfaces with reflectances so high as to be unlikely to be part of an ice-free population. In this south we find a similar distribution found by Hayne et al. (2015) based on UV properties. In the north a cluster of pixels near that pole may represent a limited frost exposure.

  11. Features of ozone intraannual variability in polar regions based on ozone sounding data obtained at the Resolute and Amundsen-Scott stations

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, A.N.; Sitnov, S.A. (AN SSSR, Institut Fiziki Atmosfery, Moscow (USSR))

    1991-04-01

    Ozone sounding data obtained at the Resolute and Amundsen-Scott stations are used to analyze ozone intraannual variability in Southern and Northern polar regions. For the Arctic, in particular, features associated with winter stratospheric warmings, stratospheric-tropospheric exchange, and the isolated evolution of surface ozone are noted. Correlative connections between ozone and temperature making it possible to concretize ozone variability mechanisms are analyzed. 31 refs.

  12. Main factors controlling the sedimentation of high-quality shale in the Wufeng–Longmaxi Fm, Upper Yangtze region

    Directory of Open Access Journals (Sweden)

    Yuman Wang

    2017-09-01

    Full Text Available In this paper, the shale of Upper Ordovician Wufeng Fm–Lower Silurian Longmaxi Fm was taken as an example to reveal the distribution patterns and the main sedimentation controlling factors of high-quality shale in the Upper Yangtze region. This study was made from the aspects of plate movement, fluctuation of sea level, palaeo-productivity, deposition rate and paleogeographic environment, based on the field outcrop sections and drilling data of the southern Sichuan Basin, together with geochemical element testing and biostratigraphical analysis results. The following findings were obtained. First, the collision and joint of Yangtze Plate and its periphery plates and the intra-plate deformation were gentle in the early stage, strong in the late stage, gentle in northwest and strong in southeast, so the sedimentation center in the Upper Yangtze region migrated to the northwest and the closure of sea area in the southern Sichuan Basin changed from weak in early stages to strong in late stages. Second, at the turning period from Ordovician to Silurian, sea levels presented the cycle change of deep–shallow–deep–shallow. Due to the combination of high sea levels and a stable ocean basin in early stages, an extensive anoxic tectonic sedimentary space favorable for organic matters preservation was formed in the sea floor. Third, due to the effect of tectonic movements and sea closure, palaeo-productivity of sea areas in the southern Sichuan Basin presented a trend of being high in the early stage and low in the late stage, and the deposition rate was also low in the early stage and high in the late stage. And fourth, extensive deposition and distribution of shale rich in organic matters and silica was mainly controlled by a stable sea basin with a low subsidence rate, a relatively high sea level, semi-closed waters and low deposition rates. To sum up, the high-quality shale in the Upper Yangtze region is characterized by multiphase

  13. Polarized neutrons

    International Nuclear Information System (INIS)

    Williams, W.G.

    1988-01-01

    The book on 'polarized neutrons' is intended to inform researchers in condensed matter physics and chemistry of the diversity of scientific problems that can be investigated using polarized neutron beams. The contents include chapters on:- neutron polarizers and instrumentation, polarized neutron scattering, neutron polarization analysis experiments and precessing neutron polarization. (U.K.)

  14. Assessment of the Global and Regional Land Hydrosphere and Its Impact on the Balance of the Geophysical Excitation Function of Polar Motion

    Science.gov (United States)

    Wińska, Małgorzata; Nastula, Jolanta; Kołaczek, Barbara

    2016-02-01

    The impact of continental hydrological loading from land water, snow and ice on polar motion excitation, calculated as hydrological angular momentum (HAM), is difficult to estimate, and not as much is known about it as about atmospheric angular momentum (AAM) and oceanic angular momentum (OAM). In this paper, regional hydrological excitations to polar motion are investigated using monthly terrestrial water storage data derived from the Gravity Recovery and Climate Experiment (GRACE) mission and from the five models of land hydrology. The results show that the areas where the variance shows large variability are similar for the different models of land hydrology and for the GRACE data. Areas which have a small amplitude on the maps make an important contribution to the global hydrological excitation function of polar motion. The comparison of geodetic residuals and global hydrological excitation functions of polar motion shows that none of the hydrological excitation has enough energy to significantly improve the agreement between the observed geodetic excitation and geophysical ones.

  15. Discrimination of coastal wetland environments in the Amazon region based on multi-polarized L-band airborne Synthetic Aperture Radar imagery

    Science.gov (United States)

    Souza-Filho, Pedro Walfir M.; Paradella, Waldir R.; Rodrigues, Suzan W. P.; Costa, Francisco R.; Mura, José C.; Gonçalves, Fabrício D.

    2011-11-01

    This study assessed the use of multi-polarized L-band images for the identification of coastal wetland environments in the Amazon coast region of northern Brazil. Data were acquired with a SAR R99B sensor from the Amazon Surveillance System (SIVAM) on board a Brazilian Air Force jet. Flights took place in the framework of the 2005 MAPSAR simulation campaign, a German-Brazilian feasibility study focusing on a L-band SAR satellite. Information retrieval was based on the recognition of the interaction between a radar signal and shallow-water morphology in intertidal areas, coastal dunes, mangroves, marshes and the coastal plateau. Regarding the performance of polarizations, VV was superior for recognizing intertidal area morphology under low spring tide conditions; HH for mapping coastal environments covered with forest and scrub vegetation such as mangrove and vegetated dunes, and HV was suitable for distinguishing transition zones between mangroves and coastal plateau. The statistical results for the classification maps expressed by kappa index and general accuracy were 83.3% and 0.734 for the multi-polarized color composition (R-HH, G-HV, B-VV), 80.7% and 0.694% for HH, 79.7% and 0.673% for VV, and 77.9% and 0.645% for HV amplitude image. The results indicate that use of multi-polarized L-band SAR is a valuable source of information aiming at the identification and discrimination of distinct geomorphic targets in tropical wetlands.

  16. Identification of fish nursery areas in a free tributary of an impoundment region, upper Uruguay River, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Alves da Silva

    2012-01-01

    Full Text Available This study aims to determine the importance of different environments of the Ligeiro River (upper Uruguay River, Brazil in fish reproduction. For this purpose, three environments (sampling sites were selected: rapids, a pool, and the mouth of the Ligeiro River. Ichthyoplankton, zooplankton, and benthos were sampled six times per month from September, 2006 to March, 2007. Zooplankton and ichthyoplankton samples were collected early in the evening with plankton nets (64 µm and 500 µm, respectively. Benthos samples were also collected early in the evening with a Van Veen dredge. Local abiotic variables (temperature, dissolved oxygen, pH, electrical conductivity, water speed, alkalinity, water hardness, and water transparency were measured simultaneously with the biotic data sampling and were complemented by regional variables (water flow and precipitation. A total of 43,475 eggs and 2,269 larvae were captured. Of these larvae, 80.1% were in the pre-flexion and larval yolk stages. Digestive tract content showed that the greatest degree of repletion among the larvae in more advanced phases occurred in the pool environment. Water speed was the main characteristic used to differentiate the river's rapids and mouth from the pool. The abundance of zooplankton and benthos was not related to the distribution of densities among the different components of the ichthyoplankton. A greater abundance of eggs and larvae with yolk was found in the rapids and river mouth. Ordination analyses showed a connection between the advanced stage larvae and the pool environment. In conclusion, the rapids and river mouth of the Ligeiro River's are important locations for fish reproduction, particularly in regard to spawning and drifting of the ichthyoplankton's initial stages, whereas the pool represents a nursery place for larval growth.O presente estudo visa determinar a importância de diferentes ambientes do rio Ligeiro (alto rio Uruguai/Brasil na reprodução dos

  17. Tuning Stilbene Photochemistry by Fluorination: State Reordering Leads to Sudden Polarization near the Franck-Condon Region.

    Science.gov (United States)

    Ioffe, Ilya N; Quick, Martin; Quick, Michael T; Dobryakov, Alexander L; Richter, Celin; Granovsky, Alex A; Berndt, Falko; Mahrwald, Rainer; Ernsting, Nikolaus P; Kovalenko, Sergey A

    2017-10-25

    Spontaneous polarization of a nonpolar molecule upon photoexcitation (the sudden polarization effect) earlier discussed for 90°-twisted alkenes is observed and calculated for planar ring-fluorinated stilbenes, trans-2,3,5,6,2',3',5',6'-octofluorostilbene (tF2356) and trans-2,3,4,5,6,2',3',4',5',6'-decafluorostilbene (tF23456). Due to the fluorination, Franck-Condon states S 1 FC and S 2 FC are dominated by the quasi-degenerate HOMO-1 → LUMO and HOMO-2 → LUMO excitations, while their interaction gives rise to a symmetry-broken zwitterionic S 1 state. After optical excitation of tF2356, one observes an ultrafast (∼0.06 ps) evolution that reflects relaxation from initial nonpolar S 3 FC to long-lived (1.3 ns in n-hexane and 3.4 ns in acetonitrile) polar S 1 . The polarity of S 1 is evidenced by a solvatochromic shift of its fluorescence band. The experimental results provide a sensitive test for quantum-chemical calculations. In particular, our calculations agree with the experiment, and raise concerns about the applicability of the common TDDFT approach to relatively simple stilbenic systems.

  18. Comparing lightning polarity and cloud microphysical properties over regions of high ground flash density in South Africa

    CSIR Research Space (South Africa)

    Simpson, LA

    2011-09-01

    Full Text Available This study aims to find a correlation between lightning polarity and microphysical properties of a storm cloud, for events where large amounts of lightning damage have occured and/or there has been a reported lightning-related fatality....

  19. Regional diagenesis of sandstone in the Upper Jurassic Morrison Formation, San Juan Basin, New Mexico and Colorado

    International Nuclear Information System (INIS)

    Hansley, P.L.

    1990-01-01

    The author reports that early authigenic mineral assemblages and vitroclastic textures are very well preserved in upper sandstones of the Upper Jurassic Morrison Formation. The distributions of the authigenic minerals were controlled, in part, by chemical gradients in a large saline, alkaline lake (Lake T'oo'dichi) that existed in late Morrison time. Sandstones on lake margins were cemented by smectite and silica, whereas sandstones nearer the lake center, in which waters were most saline and alkaline, were cemented by zeolites. Diagenetic alterations in sandstones were promoted by alkaline interstitial waters that emanated from adjacent fine-grained, tuffaceous lake beds. Metastable phases that precipitated first were replaced relatively quickly by more stable, ordered phases in the geochemically favorable environment of the closed basin setting. Elevation of temperatures above the geothermal gradient was proved by the influx of warm, deep-basin waters that locally modified early diagenetic assemblages during burial diagenesis. In organic- (and commonly also uranium ore-) bearing sandstones located primarily in the southern part of the basin, complex diagenetic assemblages resulted from water/rock reactions involving soluble organic complexes

  20. New simple mathematical model to help evaluating the extent of the late-Quaternary valley glacier in the Upper Soča Region (NW Slovenia

    Directory of Open Access Journals (Sweden)

    Miloš Bavec

    2002-06-01

    Full Text Available A simple mathematical model was developed that enables an evaluation of a valley glacier extent independently of any geological data. Based on glaciological criteria and on quantitative analysis of the glacier’s accumulation-, and ablation-areas the modeloffers an opportunity for an independent test of paleoenvironmental interpretations that are traditionally based on (often vague and difficult-to-interpret geomorphological and sedimentological information. The model is presented here through a case study from theUpper Soča River Region.

  1. A Methology for Assessing the Regional Transportation Energy Demands of Different Spatial Residential Development Scenarios: a Case Study for the Upper Housatonic River Basin, Massachusetts

    Science.gov (United States)

    Oski, J. A.; Fabos, J. G.; Gross, M.

    1982-01-01

    A method is suggested whereby regional landscape planning efforts can be aided by the use of a geographic information system to determine sites for more energy efficient residential and mixed use developments within a study area. The location of land parcels suited for residential and mixed land use developments in the Upper Housatonic River Basin Study Area in Berkshire County, Massachusetts is described as well as the three development options. Significant steps in the procedure are discussed and the computation of the transportation energy requirement is elaborated.

  2. CT-guided stellate ganglion blockade vs. radiofrequency neurolysis in the management of refractory type I complex regional pain syndrome of the upper limb

    Energy Technology Data Exchange (ETDEWEB)

    Kastler, Adrian [University Hospital CHU Gabriel Montpied, Radiology Department, Clermont-Ferrand (France); Franche Comte University, I4S Laboratory-EA 4268-IFR 133, Besancon (France); CHU Clermont-Ferrand, Hopital Gabriel Montpied, Clermont-Ferrand (France); Aubry, Sebastien; Kastler, Bruno [University Hospital CHU Jean Minjoz, Radiology and Interventional Pain Unit, Besancon (France); Franche Comte University, I4S Laboratory-EA 4268-IFR 133, Besancon (France); Sailley, Nicolas; Michalakis, Demosthene [University Hospital CHU Jean Minjoz, Radiology and Interventional Pain Unit, Besancon (France); Siliman, Gaye [University Hospital CHU St Jacques, Clinical Investigation Center, Besancon (France); Gory, Guillaume [Franche Comte University, I4S Laboratory-EA 4268-IFR 133, Besancon (France); Lajoie, Jean-Louis [University Hospital CHU Jean Minjoz, Pain evaluation and Management Unit, Besancon (France)

    2013-05-15

    To describe and evaluate the feasibility and efficacy of CT-guided radiofrequency neurolysis (RFN) vs. local blockade of the stellate ganglion in the management of chronic refractory type I complex regional pain syndrome (CRPS) of the upper limb. Sixty-seven patients were included in this retrospective study between 2000 and 2011. All suffered from chronic upper limb type I CRPS refractory to conventional pain therapies. Thirty-three patients underwent stellate ganglion blockade and 34 benefited from radiofrequency neurolysis of the stellate ganglion. CT guidance was used in both groups. The procedure was considered effective when pain relief was {>=}50 %, lasting for at least 2 years. Thirty-nine women (58.2 %) and 28 men (41.8 %) with a mean age of 49.5 years were included in the study. Univariate analysis performed on the blockade and RFN groups showed a significantly (P < 0.0001) higher success rate in the RFN group (67.6 %, 23/34) compared with the blockade group (21.2 %, 7/33) with an odds ratio of 7.76. CT-guided radiofrequency neurolysis of the stellate ganglion is a safe and successful treatment of chronic refractory type I CRPS of the upper limb. It appears to be more effective than stellate ganglion blockade. (orig.)

  3. Recent changes in sediment redistribution in the upper parts of the fluvial system of European Russia: regional aspects

    Directory of Open Access Journals (Sweden)

    O. P. Yermolaev

    2015-03-01

    Full Text Available Quantitative assessments of soil loss from cultivated land and sediment redistribution along pathways from cultivated fields to river channels have been undertaken using a range of different methods and techniques, including erosion models, detailed studies of sediment redistribution in representative catchments, monitoring of gully head retreat and evaluation of sediment deposition in ponds and small reservoirs. Most of the sediment eroded from arable land is deposited between the lower portions of the cultivated slopes and the river channels. Less than 15% of the eroded sediment is delivered to the river channels. Sediment redistribution rates in the upper parts of the fluvial system have declined during the last 25 years in both the western and eastern parts of the Russian Plain, because of a major reduction of surface runoff during snowmelt and a reduction of the area of arable land in some parts of the study area.

  4. The chemical effects on the summertime ozone in the upper troposphere and lower stratosphere over the Tibetan Plateau and the South Asian monsoon region

    Science.gov (United States)

    Gu, Yixuan; Liao, Hong; Xu, Jianming; Zhou, Guangqiang

    2018-01-01

    We use the global three-dimensional Goddard Earth Observing System chemical transport model with the Universal tropospheric-stratospheric Chemistry eXtension mechanism to examine the contributions of the chemical processes to summertime O3 in the upper troposphere and lower stratosphere (UTLS) over the Tibetan Plateau and the South Asian monsoon region (TP/SASM). Simulated UTLS O3 concentrations are evaluated by comparisons with Microwave Limb Sounder products and net chemical production of O3 (NPO3) are evaluated by comparisons with model results in previous studies. Simulations show that the chemical processes lead to an increase in O3 concentration, which is opposite to the effect of O3 transport in the UTLS over the TP/SASM region throughout the boreal summer. NPO3 in UTLS over the TP/SASM region is the largest in summer. Elevated values (0.016-0.020 Tg year-1) of the seasonal mean NPO3 are simulated to locate at 100 hPa in the TP/SASM region, where the mixing ratios of O3 are low and those of O3 precursors (NO x , VOCs, and CO) are high. The high concentrations of O3 precursors (NO x , VOCs, and CO) together with the active photochemical reactions of NO2 in the UTLS over the TP/SASM region during summertime could be important reasons for the enhancement of {NP}_{{{O}3 }} over the studied region.

  5. ST5 Observations of the Imbalance of Region 1 and 2 Field-Aligned Currents and Its Implication to the Cross-Polar Cap Pedersen Currents

    Science.gov (United States)

    Le, Guan; Slavin, J. A.; Strangeway, Robert

    2011-01-01

    In this study, we use the in-situ magnetic field observations from Space Technology 5 mission to quantify the imbalance of Region 1 (R1) and Region 2 (R2) currents. During the three-month duration of the ST5 mission, geomagnetic conditions range from quiet to moderately active. We find that the R1 current intensity is consistently stronger than the R2 current intensity both for the dawnside and the duskside large-scale field-aligned current system. The net currents flowing into (out of) the ionosphere in the dawnside (duskside) are in the order of 5% of the total R1 currents. We also find that the net currents flowing into or out of the ionosphere are controlled by the solar wind-magnetosphere interaction in the same way as the field-aligned currents themselves are. Since the net currents due to the imbalance of the R1 and R2 currents require that their closure currents flow across the polar cap from dawn to dusk as Pedersen currents, our results indicate that the total amount of the cross-polar cap Pedersen currents is in the order of 0.1 MA. This study, although with a very limited dataset, is one of the first attempts to quantify the cross-polar cap Pedersen currents. Given the importance of the Joule heating due to Pedersen currents to the high-latitude ionospheric electrodynamics, quantifying the cross-polar cap Pedersen currents and associated Joule heating is needed for developing models of the magnetosphere-ionosphere coupling.

  6. The vectoral role of several blackfly species (Diptera: Simuliidae) in relation to human onchocerciasis in the Sierra Parima and Upper Orinoco regions of Venezuela.

    Science.gov (United States)

    Basáñez, M G; Yarzábal, L; Takaoka, H; Suzuki, H; Noda, S; Tada, I

    1988-12-01

    Experimental and natural infections with Onchocerca volvulus were studied in several anthropophilic blackfly species present in the endemic area of the Upper Orinoco region of Venezuela. When fed on four different Yanomami volunteers in the Sierra Parima, the total infection rate was 31.4% for Simulium guianense in comparison with 7.5% for S. limbatum. The proportion of ingested microfilariae that entered the thorax during the first 24 hours and completed development to the infective stage was also much lower in the latter than in the former species. There was no larval development of O. volvulus in S. antillarum, but one female harboured in its head six infective larvae of a zoonotic filaria. When S. oyapokense s.l. was fed on an infected volunteer in the Upper Orinoco most flies ingested few microfilariae, and further development reached only the L1 stage. Natural infection and infectivity rates for S. guianense in two localities of the Sierra Parima were 0.2-4.0% and 1.3-10.2%, respectively, more than 50% of the L3 larvae being in the head. The corresponding data for S. oyapockense s.l. in the Upper Orinoco were 0.1-0.5%, although the only L3 larva found did not correspond to O. volvulus. It is suggested that S. guianense is the main vector of onchocerciasis in the Sierra Parima and that S. limbatum could play a secondary role. Simulium oyapockense s.l. replaces them in the Upper Orinoco and may maintain a degree of transmission, but its epidemiological importance remains to be assessed.

  7. The Contribution of Water Ice Clouds to the Water Cycle in the North Polar Region of Mars: Preliminary Analysis

    Science.gov (United States)

    Bass, D. S.; Tamppari, L. K.

    2000-01-01

    While it has long been known that Mars' north residual polar cap and the Martian regolith are significant sources of atmospheric water vapor, the amount of water vapor observed in the northern spring season by the Viking Mars Atmospheric Water Detector instrument (MAWD) cannot be attributed to cap and regolith sources alone. Kahn suggested that ice hazes may be the mechanism by which additional water is supplied to the Martian atmosphere. Additionally, a significant decrease in atmospheric water vapor was observed in the late northern summer that could not be correlated with the return of the cold seasonal C02 ice. While the detection of water ice clouds on Mars indicate that water exists in Mars' atmosphere in several different phases, the extent to which water ice clouds play a role in moving water through the Martian atmosphere remains uncertain. Work by Bass et. al. suggested that the time dependence of water ice cap seasonal variability and the increase in atmospheric water vapor depended on the polar cap center reaching 200K, the night time saturation temperature. Additionally, they demonstrated that a decrease in atmospheric water vapor may be attributed to deposition of water ice onto the surface of the polar cap; temperatures were still too warm at this time in the summer for the deposition of carbon dioxide. However, whether water ice clouds contribute significantly to this variability is unknown. Additional information is contained in original extended abstract.

  8. Regional variations in upper mantle compressional velocities beneath southern California 1. Post-shock temperatures: Their experimental determination, calculation, and implications, 2.. Ph.D. Thesis

    Science.gov (United States)

    Raikes, S. A.

    1978-01-01

    The compressional velocity within the upper mantle beneath Southern California is investigated through observations of the dependence of teleseismic P-delays at all stations of the array on the distance and azimuth to the event. The variation of residuals with azimuth was found to be as large as 1.3 sec at a single station; the delays were stable as a function of time, and no evidence was found for temporal velocity variations related to seismic activity in the area. These delays were used in the construction of models for the upper mantle P-velocity structure to depths of 150 km, both by ray tracing and inversion techniques. The models exhibit considerable lateral heterogeneity including a region of low velocity beneath the Imperial Valley, and regions of increased velocity beneath the Sierra Nevada and much of the Transverse Ranges. The development is described of a technique for the experimental determination of post-shock temperatures, and its application to several metals and silicates shocked to pressures in the range 5 to 30 GPa. The technique utilizes an infra-red radiation detector to determine the brightness temperature of the free surface of the sample after the shock wave has passed through it.

  9. Transient Upper Crustal Tear Illuminated by the Chi Chi Earthquake: Results from Strain Inversions in the Luliao Region, Taiwan

    Science.gov (United States)

    Lamont, E. A.; Lewis, J.; Byrne, T. B.; Crespi, J. M.; Rau, R.

    2010-12-01

    Modeling of earthquake focal mechanisms and coseismic GPS data from an area at the southern tip of the 1999 Chi Chi rupture suggests the existence of an evolving upper plate tear. The earthquakes occur in what we refer to as the Luliao seismic zone and define a steeply northeast-dipping tabular volume that extends from the surface to approximately 11 km. We find that the focal mechanisms from the six-month period following the 1999 Chi-Chi Earthquake yield best-fitting strain tensors that suggest the dominance of strike-slip faulting. Our strain inversions, using a micropolar continuum model, reveal orogen-perpendicular (NW-SE) minimum stretching (i.e., shortening) and orogen-parallel (NE-SW) maximum stretching. Additionally, our inversions indicate plane strain with positive, non-zero relative vorticity values, suggestive of counter-clockwise (map view) block rotations. Published coseismic GPS data provide additional evidence that this tabular volume of crust is the locus of strike-slip faulting accompanied by block rotation. Preliminary 2D strain inversions for GPS stations that span the inverted focal mechanisms reveal negative (counterclockwise) rotation values and principal strain axes that are generally consistent with our focal mechanism inversions. We interpret our findings to reflect an accommodation zone that is activated by differential westward expansion of the foreland fold and thrust belt. In particular, this zone separates an area of greater westward propagation near Taichung from an area of lesser propagation to the south near Chiayi. Differential expansion of the orogen appears to be influenced by an eastward pointing, lower-plate promontory south of the Sanyi-Puli seismic zone. Unlike the Luliao events, the Sanyi-Puli seismic zone extends from the near surface to approximately 30 km and we have interpreted it as a reactivated continental margin fracture zone inherited from South China Sea rifting. The lower-plate promontory is coincident with the

  10. Detailed EXOSAT and optical observations of the intermediate polar 3A0729+103: discovery of two medium energy X-ray emission regions

    International Nuclear Information System (INIS)

    McHardy, I.M.; Pye, J.P.; Fairall, A.P.; Menzies, J.W.

    1987-01-01

    EXOSAT observations of the intermediate polar cataclysmic variable 3A0729+103 reveal a strong orbital modulation, with the 2-4KeV X-rays being significantly more modulated than the 4-6keV X-rays, indicative of photoelectric absorption. The 913 second modulation which is very prominent in the optical light curve, is weakly detected in the medium-energy X-ray light curve, confirming that it represents the white dwarf spin period. These observations are well explained by a combination of two sources of medium-energy X-ray emission. The presence of two emission regions is also clearly seen in the optical spectroscopy, particularly in the intensity of the He II4686 line which has two peaks during the orbit. The authors identify the two optical emission regions with the two X-ray emission regions. (author)

  11. Streamflow in the upper Mississippi river basin as simulated by SWAT driven by 20{sup th} century contemporary results of global climate models and NARCCAP regional climate models

    Energy Technology Data Exchange (ETDEWEB)

    Takle, Eugene S.; Jha, Manoj; Lu, Er; Arritt, Raymond W.; Gutowski, William J. [Iowa State Univ. Ames, IA (United States)

    2010-06-15

    We use Soil and Water Assessment Tool (SWAT) when driven by observations and results of climate models to evaluate hydrological quantities, including streamflow, in the Upper Mississippi River Basin (UMRB) for 1981-2003 in comparison to observed streamflow. Daily meteorological conditions used as input to SWAT are taken from (1) observations at weather stations in the basin, (2) daily meteorological conditions simulated by a collection of regional climate models (RCMs) driven by reanalysis boundary conditions, and (3) daily meteorological conditions simulated by a collection of global climate models (GCMs). Regional models used are those whose data are archived by the North American Regional Climate Change Assessment Program (NARCCAP). Results show that regional models correctly simulate the seasonal cycle of precipitation, temperature, and streamflow within the basin. Regional models also capture interannual extremes represented by the flood of 1993 and the dry conditions of 2000. The ensemble means of both the GCM-driven and RCM-driven simulations by SWAT capture both the timing and amplitude of the seasonal cycle of streamflow with neither demonstrating significant superiority at the basin level. (orig.)

  12. Simulation of Runoff Changes Caused by Cropland to Forest Conversion in the Upper Yangtze River Region, SW China

    Science.gov (United States)

    Yu, Pengtao; Wang, Yanhui; Coles, Neil; Xiong, Wei; Xu, Lihong

    2015-01-01

    The "Grain for Green Project" is a country-wide ecological program to converse marginal cropland to forest, which has been implemented in China since 2002. To quantify influence of this significant vegetation change, Guansihe Hydrological (GSH) Model, a validated physically-based distributed hydrological model, was applied to simulate runoff responses to land use change in the Guansihe watershed that is located in the upper reaches of the Yangtze River basin in Southwestern China with an area of only 21.1 km2. Runoff responses to two single rainfall events, 90 mm and 206 mm respectively, were simulated for 16 scenarios of cropland to forest conversion. The model simulations indicated that the total runoff generated after conversion to forest was strongly dependent on whether the land was initially used for dry croplands without standing water in fields or constructed (or walled) paddy fields. The simulated total runoff generated from the two rainfall events displayed limited variation for the conversion of dry croplands to forest, while it strongly decreased after paddy fields were converted to forest. The effect of paddy terraces on runoff generation was dependent on the rainfall characteristics and antecedent moisture (or saturation) conditions in the fields. The reduction in simulated runoff generated from intense rainfall events suggested that afforestation and terracing might be effective in managing runoff and had the potential to mitigate flooding in southwestern China. PMID:26192181

  13. Active monitoring with lichens in the Linz region (Upper Austria); Aktives Monitoring mit Flechten in der Landeshauptstadt Linz (Oberoesterreich, Oesterreich)

    Energy Technology Data Exchange (ETDEWEB)

    Heber, I; Heber, W; Tuerk, R

    1993-12-31

    A bio-monitoring project to asses air quality was run in the city of Linz (Upper Austria) between October 1990 and November 1991. The project used Hypogymnia physodes samples which were exposed according to VDI specifications (No. 3799). The climatic conditions of October 1990 resulted in a high atmospheric pollution load which caused almost all of the lichens exposed (82 plates) to die within four weeks. New samples were exposed in November 1990 and their damage rates indicated a clear zoning of emission input loads of the city of Linz in the period December 1990 to March 1991. (orig.) [Deutsch] In der Landeshauptstadt Linz (Oesterreich, Oberoesterreich) wurde im Zeitraum von Oktober 1990 bis November 1991 ein Biomonitoring-Projekt zur Bewertung der Luftguete durchgefuehrt. Dabei wurden Proben von Hypogymnia physodes entsprechend den Anleitungen des VDI (Nr. 3799) exponiert. Bereits waehrend des Oktober 1990 fuehrten die klimatischen Gegebenheiten zu einer hohen Belastung der Atmosphaere mit Schadstoffen, so dass fast alle exponierten Flechten (82 Tafeln) innerhalb von vier Wochen vollstaendig abstarben. Die im November 1990 neu exponierten Proben liessen fuer den Zeitraum Dezember 1990 bis Maerz 1991 bereits eine deutliche Zonierung der Immissionsbelastung in der Stadt Linz aufgrund der Schaedigungsraten der Flechten erkennen. (orig.)

  14. In vivo and in vitro changes in neurochemical parameters related to mercury concentrations from specific brain regions of polar bears (Ursus maritimus).

    Science.gov (United States)

    Krey, Anke; Kwan, Michael; Chan, Hing Man

    2014-11-01

    Mercury (Hg) has been detected in polar bear brain tissue, but its biological effects are not well known. Relationships between Hg concentrations and neurochemical enzyme activities and receptor binding were assessed in the cerebellum, frontal lobes, and occipital lobes of 24 polar bears collected from Nunavik (Northern Quebec), Canada. The concentration-response relationship was further studied with in vitro experiments using pooled brain homogenate of 12 randomly chosen bears. In environmentally exposed brain samples, there was no correlative relationship between Hg concentration and cholinesterase (ChE) activity or muscarinic acetylcholine receptor (mAChR) binding in any of the 3 brain regions. Monoamine oxidase (MAO) activity in the occipital lobe showed a negative correlative relationship with total Hg concentration. In vitro experiments, however, demonstrated that Hg (mercuric chloride and methylmercury chloride) can inhibit ChE and MAO activities and muscarinic mAChR binding. These results show that Hg can alter neurobiochemical parameters but the current environmental Hg exposure level does have an effect on the neurochemistry of polar bears from northern Canada. © 2014 SETAC.

  15. The influence of charge and the distribution of charge in the polar region of phospholipids on the activity of UDP-glucuronosyltransferase.

    Science.gov (United States)

    Zakim, D; Eibl, H

    1992-07-05

    Studies of the mechanism of lipid-induced regulation of the microsomal enzyme UDP-glucuronosyltransferase have been extended by examining the influence of charge within the polar region on the ability of lipids to activate delipidated pure enzyme. The effects of net negative charge, of charge separation in phosphocholine, and of the distribution of charge in the polar region of lipids were studied using the GT2p isoform isolated from pig liver. Prior experiments have shown that lipids with net negative charge inhibit the enzyme (Zakim, D., Cantor, M., and Eibl, H. (1988) J. Biol. Chem. 263, 5164-5169). The current experiments show that the extent of inhibition on a molar basis increases as the net negative charge increases from -1 to -2. The inhibitory effect of negatively charged lipids is on the functional state of the enzyme and is not due to electrostatic repulsion of negatively charged substrates of the enzyme. Although the inhibitory effect of net negative charge is removed when negative charge is balanced by a positive charge due to a quaternary nitrogen, neutrality of the polar region is not a sufficient condition for activation of the enzyme. In addition to a balance of charge between Pi and the quaternary nitrogen, the distance between the negative and positive charges and the orientation of the dipole created by them are critical for activation of GT2p. The negative and positive charges must be separated by the equivalent of three -CH2- groups for optimal activation by a lipid. Shortening this distance by one -CH2- unit leads to a lipid that is ineffective in activating the enzyme. Reversal of the orientation of the dipole in which the negative charge is on the polymethylene side of the lipid-water interface and the positive charge extends into water also produces a lipid that is not effective for activating GT2p. On the other hand, lipids with phosphoserine as the polar region, which has the "normal" P-N distance but carries a net negative charge, do

  16. Measurement of the vector np → dπ{sup 0}π{sup 0} reaction with polarized beam in the region of the d*(2380) resonance

    Energy Technology Data Exchange (ETDEWEB)

    Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Johansson, T.; Marciniewski, P.; Wolke, M.; Zlomanczuk, J. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Department of Nuclear Physics, Warsaw (Poland); Bardan, W.; Ciepal, I.; Czerwinski, E.; Jarczyk, L.; Kamys, B.; Khatri, G.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Rudy, Z.; Rundel, O.; Schaetti-Ozerianska, I.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J. [Jagiellonian University, Institute of Physics, Krakow (Poland); Bashkanov, M. [University of Edinburgh, James Clerk Maxwell Building, School of Physics and Astronomy, Edinburgh (United Kingdom); Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Bergmann, F.S.; Demmich, K.; Huesken, N.; Khoukaz, A.; Sitterberg, K.; Taeschner, A. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Berlowski, M.; Stepaniak, J. [National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Bhatt, H.; Varma, R. [Indian Institute of Technology Bombay, Department of Physics, Powai, Maharashtra (India); Bondar, A.; Kuzmin, A.; Shwartz, B. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Zurek, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Clement, H. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); University of Tuebingen, Kepler Center for Astro- and Particle Physics, Tuebingen (Germany); Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P. [Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Elektronik und Analytik, Juelich (Germany); Eyrich, W.; Zink, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Fedorets, P. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Foehl, K. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Goswami, A.; Roy, A. [Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (India); Grigoryev, K. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Petersburg Nuclear Physics Institute, High Energy Physics Division, Gatchina, Leningrad district (Russian Federation); Kirillov, D.A.; Piskunov, N.M. [Joint Institute for Nuclear Physics, Veksler and Baldin Laboratory of High Energiy Physics, Dubna, Moscow region (Russian Federation); Klos, B.; Stephan, E. [University of Silesia, August Chelkowski Institute of Physics, Katowice (Poland); Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A. [Polish Academy of Sciences, The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Kupsc, A.; Pszczel, D. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Lalwani, K. [Malaviya National Institute of Technology Jaipur, JLN Marg, Department of Physics, Jaipur, Rajasthan (India); Maier, R.; Stroeher, H. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, JARA-FAME, Juelich Aachen Research Alliance, Juelich (Germany); RWTH Aachen, Aachen (Germany); Perez del Rio, E. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Pyszniak, A. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Jagiellonian University, Institute of Physics, Krakow (PL); Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, JARA-FAME, Juelich Aachen Research Alliance, Juelich (DE); RWTH Aachen, Aachen (DE); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (DE); Sawant, S. [Indian Institute of Technology Bombay, Department of Physics, Powai, Maharashtra (IN); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Skorodko, T. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (DE); University of Tuebingen, Kepler Center for Astro- and Particle Physics, Tuebingen (DE); Tomsk State University, Department of Physics, Tomsk (RU); Sopov, V. [State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (RU); Yamamoto, A. [High Energy Accelerator Research Organisation KEK, Tsukuba, Ibaraki (JP); Zabierowski, J. [National Centre for Nuclear Research, Department of Astrophysics, Lodz (PL); Collaboration: WASA-at-COSY Collaboration

    2016-05-15

    We report on a high-statistics measurement of the most basic double-pionic fusion reaction vector np→dπ{sup 0}π{sup 0} over the energy region of the d*(2380) resonance by use of a polarized deuteron beam and observing the double fusion reaction in the quasifree scattering mode. The measurements were performed with the WASA detector setup at COSY. The data reveal substantial analyzing powers and confirm conclusions about the d* resonance obtained from unpolarized measurements. We also confirm the previous unpolarized data obtained under complementary kinematic conditions. (orig.)

  17. Quantitative controls on location and architecture of carbonate depositional sequences: upper miocene, cabo de gata region, se Spain

    Science.gov (United States)

    Franseen, E.K.; Goldstein, R.H.; Farr, M.R.

    1998-01-01

    Sequence stratigraphy, pinning-point relative sea-level curves, and magnetostratigraphy provide the quantitative data necessary to understand how rates of sea-level change and different substrate paleoslopes are dominant controls on accumulation rate, carbonate depositional sequence location, and internal architecture. Five third-order (1-10 my) and fourth-order (0.1-1.0 my) upper Miocene carbonate depositional sequences (DS1A, DS1B, DS2, DS3, TCC) formed with superimposed higher-frequency sea-level cycles in an archipelago setting in SE Spain. Overall, our study indicates when areas of high substrate slope (> 15??) are in shallow water, independent of climate, the location and internal architecture of carbonate deposits are not directly linked to sea-level position but, instead, are controlled by location of gently sloping substrates and processes of bypass. In contrast, if carbonate sediments are generated where substrates of low slope ( 15.6 cm/ky to ??? 2 cm/ky and overall relative sea level rose at rates of 17-21.4 cm/ky. Higher frequency sea-level rates were about 111 to more than 260 cm/ky, producing onlapping, fining- (deepening-) upward cycles. Decreasing accumulation rates resulted from decreasing surface area for shallow-water sediment production, drowning of shallow-water substrates, and complex sediment dispersal related to the archipelago setting. Typical systems tract and parasequence development should not be expected in "bypass ramp" settings; facies of onlapping strata do not track base level and are likely to be significantly different compared to onlapping strata associated with coastal onlap. Basal and upper DS2 reef megabreccias (indicating the transition from cool to warmer climatic conditions) were eroded from steep upslope positions and redeposited downslope onto areas of gentle substrate during rapid sea-level falls (> 22.7 cm/ky) of short duration. Such rapid sea-level falls and presence of steep slopes are not conducive to formation of

  18. Seismic Velocity Structure of the Pacific Upper Mantle in the NoMelt Region from Finite-Frequency Traveltime Tomography

    Science.gov (United States)

    Hung, S. H.; Lin, P. Y.; Gaherty, J. B.; Russell, J. B.; Jin, G.; Collins, J. A.; Lizarralde, D.; Evans, R. L.; Hirth, G.

    2017-12-01

    Surface wave dispersion and magnetotelluric survey from the NoMelt Experiment conducted on 70 Ma central Pacific seafloor revealed an electrically resistive, high shear wave velocity lid of 80 km thick underlain by a non-highly conductive, low-velocity layer [Sarafian et al., 2015; Lin et al., 2016]. The vertical structure of the upper mantle consistent with these observational constraints suggests a plausible convection scenario, where the seismically fast, dehydrated lithosphere preserving very strong fossil spreading fabric moves at a constant plate speed over the hydrated, melt-free athenospheric mantle with the presence of either pressure-driven return flow or thermally-driven small scale circulation. To explore 3-D variations in compressional shear wave velocities related to the lithospheric and asthenospheric mantle dynamics, we employ a multichannel cross correlation method to measure relative traveltime residuals based on the vertical P and traverse S waveforms filtered at 10-33 s from telseismic earthquakes at epicentral distance between 30 and 98 degrees. The obtained P and S residuals show on average peak-to-peak variations of ±0.5 s and ±1 s, respectively, across the NoMelt OBS array. Particularly, the P residuals for most of the events display an asymmetrical pattern with respect to an axis oriented nearly N-S to NE-SW through the array. Preliminary ray-based P tomography results reveal similar asymmetric variations in the uppermost 100 km mantle. To verify the resulting structural features, we will further perform both the P and S traveltime tomography and resolution tests based on a multiscale finite-frequency approach which properly takes into account both the 3D off-path sensitivities of the measured residuals and data-adaptive resolution of the model.

  19. Etiology and outcome in patients with upper gastrointestinal bleeding: Study on 4747 patients in the central region of Iran.

    Science.gov (United States)

    Minakari, Mohammad; Badihian, Shervin; Jalalpour, Pooyan; Sebghatollahi, Vahid

    2017-04-01

    Upper gastrointestinal bleeding (UGIB) is a threatening condition leading to urgent hospitalization. This study aims to investigate etiology and outcome in UGIB patients in Iran. Medical records of GIB patients admitted to Alzahra referral hospital (in Isfahan) during 2010-2015 were retrospectively reviewed for demographic data, comorbidities, history of smoking and taking non-steroidal anti-inflammatory drugs (NSAIDs), presenting symptoms, endoscopic findings, therapeutic endoscopy, blood products' infusion, surgical intervention, rebleeding, and mortality. A total of 4747 patients were enrolled in the study (69.2% men, mean age = 55.46 ± 21.98 years). Hematemesis was the most frequent presenting symptom (63.5%). Peptic ulcer (duodenal ulcer in most cases) was seen as the main reason for UGIB (42.4%). Rebleeding (present in 16.5% of patients) was found to be more frequent in patients with older age, presenting sign of hematochezia and hypotension, history of taking NSAIDs and smoking, presence of comorbidities, history of bleeding because of UGI tract neoplasm and esophageal varices, history of needing blood products' infusion, and history of therapeutic endoscopy or surgical intervention (P < 0.005). We found that mortality (5.5% in total) was also higher in the same group of patients that were seen to have a higher tendency for rebleeding (P < 0.005). Peptic ulcers are the most common cause of UGIB. Comorbidities, hemodynamic instability, high-risk endoscopic stigmata, history of smoking and taking NSAIDs, gastric and esophageal malignancies, may be important predisposing factors for rebleeding and mortality in patients with UGIB. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  20. Classification and Use of Natural and Anthropogenic Soils by Indigenous Communities of the Upper Amazon Region of Colombia

    OpenAIRE

    Peña-Venegas, C.P.; Stomph, T.J.; Verschoor, G.; Echeverri, J.A.; Struik, P.C.

    2016-01-01

    Outsiders often oversimplify Amazon soil use by assuming that abundantly available natural soils are poorly suited to agriculture and that sporadic anthropogenic soils are agriculturally productive. Local perceptions about the potentials and limitations of soils probably differ, but information on these perceptions is scarce. We therefore examined how four indigenous communities in the Middle Caquetá River region in the Colombian Amazon classify and use natural and anthropogenic soils. The st...

  1. Polarized particles in storage rings

    International Nuclear Information System (INIS)

    Derbenev, Ya.S.; Kondratenko, A.M.; Serednyakov, S.I.; Skrinskij, A.N.; Tumajkin, G.M.; Shatunov, Yu.M.

    1977-01-01

    Experiments with polarized beams on the VEPP-2M and SPEAK storage rings are described. Possible methods of producing polarized particle beams in storage rings as well as method of polarization monitoring are counted. Considered are the processes of radiation polarization of electrons and positrons. It is shown, that to preserve radiation polarization the introduction of regions with a strong sign-variable magnetic field is recommended. Methods of polarization measurement are counted. It is suggested for high energies to use dependence of synchrotron radiation power on transverse polarization of electrons and positrons. Examples of using polarizability of colliding beams in storage rings are presented

  2. Appearance and chronology of Textile ceramics in the Middle and Upper Volga region: critical comparison of conventional 14C-, AMS- and typological chronologies

    Directory of Open Access Journals (Sweden)

    Lavento Mika T.

    2015-06-01

    Full Text Available The article offers a comparison of three different methods of chronology construction – conventional 14C (radiocarbon dating, AMS (accelerator mass-spectrometry dating and the so called typological chronology – to date the textile ceramics of the Bronze – Early Iron Age in the Northern Coniferous Zone of Europe, from the Upper and Middle Volga and Kama Rivers to the Baltic region and Scandinavia. The Textile Ceramics Culture (also known as “Net”, “Pseudo-textile”, “Spun-and-speckled” is often associated with a Finnish-speaking community from the Bronze – beginning of the Iron Age. The earliest date of the Textile Ceramics sites on the Middle Oka River is presumably considered to be the 18 th century BC. Datings of the reference sites in the Middle Volga region were fixed within the 15 th – 8 th centuries BC. Comparing these data with the AMS chronology available for the materials from Finland and Estonia, the authors conclude that appearance of the Textile Ceramics was almost synchronous in the Volga and the Baltic regions, although chronology of the early tradition of the Textile Ceramics seems to be different in these areas. The results of yet a small number of AMS dates should be treated only as preliminary. However, AMS-dating seems to be the most efficient tool for further refining of the Textile Ceramics chronology over a vast territory, including in the Volga region.

  3. Their grass is greener but ours is sweeter - thoroughbred breeding and water management in the Upper Hunter region of New South Wales, Australia

    Energy Technology Data Exchange (ETDEWEB)

    McManus, P. [University of Sydney, Sydney, NSW (Australia). School for Geoscience

    2008-05-15

    The Upper Hunter region (in New South Wales (NSW) around Scone is reputed to be the second most significant thoroughbred breeding region in the world after the Bluegrass region of Kentucky. This article identifies the importance and cultural constructions of grass, and hence water, in the thoroughbred breeding industry in this region. Thoroughbred stud managers attempt to produce environments attractive to potential horse purchasers and owners with mares to be mated. These environments are constructed from perceptions of how a thoroughbred stud should appear, and from the physical conditions of specific locations. One perception is that the grass should be green. There are differing opinions in the thoroughbred breeding industry about the nutritional value of irrigated grasses, the role of these grasses in horse development and the associated access to, cost of and efficacy of water used for this purpose. The paper concludes that effective water management in this industry is only possible if various cultures of nature are understood, where necessary challenged, and subsequently included in policy and planning.

  4. Brain region-specific perfluoroalkylated sulfonate (PFSA) and carboxylic acid (PFCA) accumulation and neurochemical biomarker responses in east Greenland polar bears (Ursus maritimus).

    Science.gov (United States)

    Eggers Pedersen, Kathrine; Basu, Niladri; Letcher, Robert; Greaves, Alana K; Sonne, Christian; Dietz, Rune; Styrishave, Bjarne

    2015-04-01

    Perfluoroalkyl substances (PFASs) is a growing class of contaminants in the Arctic environment, and include the established perfluorinated sulfonates (PFSAs; especially perfluorooctane sulfonate (PFOS)) and carboxylic acids (PFCAs). PFSAs and PFCAs of varying chain length have been reported to bioaccumulate in lipid rich tissues of the brain among other tissues such as liver, and can reach high concentrations in top predators including the polar bear. PFCA and PFSA bioaccummulation in the brain has the potential to pose neurotoxic effects and therefore we conducted a study to investigate if variations in neurochemical transmitter systems i.e. the cholinergic, glutaminergic, dopaminergic and GABAergic, could be related to brain-specific bioaccumulation of PFASs in East Greenland polar bears. Nine brain regions from nine polar bears were analyzed for enzyme activity (monoamine oxidase (MAO), acetylcholinesterase (AChE) and glutamine synthetase (GS)) and receptor density (dopamine-2 (D2), muscarinic cholinergic (mAChR) and gamma-butyric acid type A (GABA-A)) along with PFSA and PFCA concentrations. Average brain ∑PFSA concentration was 25ng/g ww where PFOS accounted for 91%. Average ∑PFCA concentration was 88ng/g ww where PFUnDA, PFDoDA and PFTrDA combined accounted for 79%. The highest concentrations of PFASs were measured in brain stem, cerebellum and hippocampus. Correlative analyses were performed both across and within brain regions. Significant positive correlations were found between PFASs and MAO activity in occipital lobe (e.g. ∑PFCA; rp=0.83, p=0.041, n=6) and across brain regions (e.g. ∑PFCA; rp=0.47, p=0.001, ∑PFSA; rp=0.44, p>0.001; n=50). GABA-A receptor density was positively correlated with two PFASs across brain regions (PFOS; rp=0.33, p=0.02 and PFDoDA; rp=0.34, p=0.014; n=52). Significant negative correlations were found between mAChR density and PFASs in cerebellum (e.g. ∑PFCA; rp=-0.95, p=0.013, n=5) and across brain regions (e.g.

  5. The disappearance of Picea at the end of Upper Pleistocene in the Basque-Cantabrian region: climatic and anthropogenic factors

    International Nuclear Information System (INIS)

    Uzquiano, P.

    1995-01-01

    Charcoal analysis from archaeological sites in Cantabrian region (North of Spain) has yielded evidence of Picea charcoal in Late-Wurmian sediments. Taking into account the behaviour of this taxon in Quaternary climatic cycles, data suggest the presence of small localities of low-density populations near each catchment area of prehistoric settlements. The different function of each site and hunter-gatherers'logistical moves closer to the economic resources are responsible for the presence or absence of Picea, and for the disappearance of its last localities. (author). 16 refs., 4 figs

  6. Radionuclide content in the Upper Vistula River sediments in a coal mining region in Poland (east-central Europe)

    International Nuclear Information System (INIS)

    Jasinska, M.; Mietelski, J.W.; Pociask-Karteczka, J.

    1998-01-01

    Hard coal mining activity is one of the Technologically Enhanced Natural Radiation sources introduced more than a hundred years ago in the southern part of Poland. This study of radionuclides (K-40, Ra-226, Ra-228) in river sediments showed the principal factors determining the specific activity of radionuclides are distance from mines and sorption by clay particles in river sediments. The K-40 specific activity varies between 185 and 595 Bq/kg. The highest Ra-228 and Ra-226 specific activities, 280-610 and 205-415 Bq/kg, respectively, were detected in sediments of the Vistula in the vicinity of Silesia region. 7 refs., 1 fig., 3 tabs

  7. Trends and Variability of North Pacific Polar Lows

    Directory of Open Access Journals (Sweden)

    Fei Chen

    2013-01-01

    Full Text Available The 6-hourly 1948–2010 NCEP 1 reanalyses have been dynamically downscaled for the region of the North Pacific. With a detecting-and-tracking algorithm, the climatology of North Pacific Polar Lows has been constructed. This derived climatology is consistent with the limited observational evidence in terms of frequency and spatial distribution. The climatology exhibits strong year-to-year variability but weak decadal variability and a small positive trend. A canonical correlation analysis describes the conditioning of the formation of Polar Lows by characteristic seasonal mean flow regimes, which favor, or limit, cold air outbreaks and upper air troughs.

  8. A regional composite-face effect for species-specific recognition: Upper and lower halves play different roles in holistic processing of monkey faces.

    Science.gov (United States)

    Wang, Zhe; Quinn, Paul C; Jin, Haiyang; Sun, Yu-Hao P; Tanaka, James W; Pascalis, Olivier; Lee, Kang

    2018-04-25

    Using a composite-face paradigm, we examined the holistic processing induced by Asian faces, Caucasian faces, and monkey faces with human Asian participants in two experiments. In Experiment 1, participants were asked to judge whether the upper halves of two faces successively presented were the same or different. A composite-face effect was found for Asian faces and Caucasian faces, but not for monkey faces. In Experiment 2, participants were asked to judge whether the lower halves of the two faces successively presented were the same or different. A composite-face effect was found for monkey faces as well as for Asian faces and Caucasian faces. Collectively, these results reveal that own-species (i.e., own-race and other-race) faces engage holistic processing in both upper and lower halves of the face, but other-species (i.e., monkey) faces engage holistic processing only when participants are asked to match the lower halves of the face. The findings are discussed in the context of a region-based holistic processing account for the species-specific effect in face recognition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Analyzing power measurement of pp elastic scattering in the Coulomb-nuclear interference region with the 200-GeV/c polarized-proton beam at Fermilab

    International Nuclear Information System (INIS)

    Akchurin, N.; Langland, J.; Onel, Y.; Bonner, B.E.; Corcoran, M.D.; Cranshaw, J.; Nessi-Tedaldi, F.; Nessi, M.; Nguyen, C.; Roberts, J.B.; Skeens, J.; White, J.L.; Bravar, A.; Giacomich, R.; Penzo, A.; Schiavon, P.; Zanetti, A.; Bystricky, J.; Lehar, F.; de Lesquen, A.; van Rossum, L.; Cossairt, J.D.; Read, A.L.; Derevschikov, A.A.; Matulenko, Y.A.; Meschanin, A.P.; Nurushev, S.B.; Patalakha, D.I.; Rykov, V.L.; Solovyanov, V.L.; Vasiliev, A.N.; Grosnick, D.P.; Hill, D.A.; Laghai, M.; Lopiano, D.; Ohashi, Y.; Shima, T.; Spinka, H.; Stanek, R.W.; Underwood, D.G.; Yokosawa, A.; Funahashi, H.; Goto, Y.; Imai, K.; Itow, Y.; Makino, S.; Masaike, A.; Miyake, K.; Nagamine, T.; Saito, N.; Yamashita, S.; Iwatani, K.; Kuroda, K.; Michalowicz, A.; Luehring, F.C.; Miller, D.H.; Maki, T.; Pauletta, G.; Rappazzo, G.F.; Salvato, G.; Takashima, R.

    1993-01-01

    The analyzing power A N of proton-proton elastic scattering in the Coulomb-nuclear interference region has been measured using the 200-GeV/c Fermilab polarized proton beam. A theoretically predicted interference between the hadronic non-spin-flip amplitude and the electromagnetic spin-flip amplitude is shown for the first time to be present at high energies in the region of 1.5x10 -3 to 5.0x10 -2 (GeV/c) 2 four-momentum transfer squared, and our results are analyzed in connection with theoretical calculations. In addition, the role of possible contributions of the hadronic spin-flip amplitude is discussed

  10. Enhanced spin polarization of elastic electron scattering from alkaline-earth-metal atoms in Ramsauer-Townsend and low-lying shape resonance regions

    International Nuclear Information System (INIS)

    Yuan, J.; Zhang, Z.

    1993-01-01

    Spin polarizations (SP's) of elastic electron scattering from alkaline-earth-metal atoms in Ramsauer-Townsend (RT) and low-lying shape resonance (SR) regions are calculated using a relativistic method. The detailed SP distributions both with scattering angle and with electron energy are presented via the energy- and angle-dependent surfaces of SP parameters. It is shown that the SP effects of the collisions of electrons with Ca, Sr, and Ba atoms in the RT region are significant in a considerable area on the energy-angle plane and that the spin-orbit interaction is well increased around the low-lying p-wave SR states of Be and Mg and the d-wave SR states of Ca, Sr, and Ba

  11. A Habitat-based Wind-Wildlife Collision Model with Application to the Upper Great Plains Region

    Energy Technology Data Exchange (ETDEWEB)

    Forcey, Greg, M.

    2012-08-28

    Most previous studies on collision impacts at wind facilities have taken place at the site-specific level and have only examined small-scale influences on mortality. In this study, we examine landscape-level influences using a hierarchical spatial model combined with existing datasets and life history knowledge for: Horned Lark, Red-eyed Vireo, Mallard, American Avocet, Golden Eagle, Whooping Crane, red bat, silver-haired bat, and hoary bat. These species were modeled in the central United States within Bird Conservation Regions 11, 17, 18, and 19. For the bird species, we modeled bird abundance from existing datasets as a function of habitat variables known to be preferred by each species to develop a relative abundance prediction for each species. For bats, there are no existing abundance datasets so we identified preferred habitat in the landscape for each species and assumed that greater amounts of preferred habitat would equate to greater abundance of bats. The abundance predictions for bird and bats were modeled with additional exposure factors known to influence collisions such as visibility, wind, temperature, precipitation, topography, and behavior to form a final mapped output of predicted collision risk within the study region. We reviewed published mortality studies from wind farms in our study region and collected data on reported mortality of our focal species to compare to our modeled predictions. We performed a sensitivity analysis evaluating model performance of 6 different scenarios where habitat and exposure factors were weighted differently. We compared the model performance in each scenario by evaluating observed data vs. our model predictions using spearmans rank correlations. Horned Lark collision risk was predicted to be highest in the northwestern and west-central portions of the study region with lower risk predicted elsewhere. Red-eyed Vireo collision risk was predicted to be the highest in the eastern portions of the study region and in

  12. Classification and Use of Natural and Anthropogenic Soils by Indigenous Communities of the Upper Amazon Region of Colombia.

    Science.gov (United States)

    Peña-Venegas, C P; Stomph, T J; Verschoor, G; Echeverri, J A; Struik, P C

    Outsiders often oversimplify Amazon soil use by assuming that abundantly available natural soils are poorly suited to agriculture and that sporadic anthropogenic soils are agriculturally productive. Local perceptions about the potentials and limitations of soils probably differ, but information on these perceptions is scarce. We therefore examined how four indigenous communities in the Middle Caquetá River region in the Colombian Amazon classify and use natural and anthropogenic soils. The study was framed in ethnopedology: local classifications, preferences, rankings, and soil uses were recorded through interviews and field observations. These communities recognized nine soils varying in suitability for agriculture. They identified anthropogenic soils as most suitable for agriculture, but only one group used them predominantly for their swiddens. As these communities did not perceive soil nutrient status as limiting, they did not base crop-site selection on soil fertility or on the interplay between soil quality and performance of manioc genetic resources.

  13. Regional stratigraphy and its dependency on tectonic movements (case study: Upper Cretaceous and Paleogene stages in Western Siberia)

    International Nuclear Information System (INIS)

    Podobina, V

    2015-01-01

    Multiscale and divergent tectonic movements have been identified in Western Siberia of which first - order movements caused transgressions and regressions, as well as the partial formation of sediments. As a result of tectonic movement direction turn, no transgression was observed in the cross-sections of Campanian and Danian central section and in the Priabonian top section. During second-order tectonic movements and undirectional transgression insignificant bed thicknesses and channels were formed. Such movements could have included different tectonic activities within the western and eastern parts of the region limited by the Koltogorsk-Urengoy Rift. Third-order tectonic movement of moderate amplitude promoted either extension, contraction or even depth variations of the marine basin itself

  14. Upper mantle structure of shear-waves velocities and stratification of anisotropy in the Afar Hotspot region

    Science.gov (United States)

    Sicilia, D.; Montagner, J.-P.; Cara, M.; Stutzmann, E.; Debayle, E.; Lépine, J.-C.; Lévêque, J.-J.; Beucler, E.; Sebai, A.; Roult, G.; Ayele, A.; Sholan, J. M.

    2008-12-01

    The Afar area is one of the biggest continental hotspots active since about 30 Ma. It may be the surface expression of a mantle "plume" related to the African Superswell. Central Africa is also characterized by extensive intraplate volcanism. Around the same time (30 Ma), volcanic activity re-started in several regions of the African plate and hotspots such as Darfur, Tibesti, Hoggar and Mount Cameroon, characterized by a significant though modest volcanic production. The interactions of mantle upwelling with asthenosphere, lithosphere and crust remain unclear and seismic anisotropy might help in investigating these complex interactions. We used data from the global seismological permanent FDSN networks (GEOSCOPE, IRIS, MedNet, GEO- FON, etc.), from the temporary PASSCAL experiments in Tanzania and Saudi Arabia and a French deployment of 5 portable broadband stations surrounding the Afar Hotspot. A classical two-step tomographic inversion from surface waves performed in the Horn of Africa with selected Rayleigh wave and Love wave seismograms leads to a 3D-model of both S V velocities and azimuthal anisotropy, as well as radial SH/ SV anisotropy, with a lateral resolution of 500 km. The region is characterized by low shear-wave velocities beneath the Afar Hotspot, the Red Sea, the Gulf of Aden and East of the Tanzania Craton to 400 km depth. High velocities are present in the Eastern Arabia and the Tanzania Craton. The results of this study enable us to rule out a possible feeding of the Central Africa hotspots from the "Afar plume" above 150-200 km. The azimuthal anisotropy displays a complex pattern near the Afar Hotspot. Radial anisotropy, although poorly resolved laterally, exhibits S H slower than S V waves down to about 150 km depth, and a reverse pattern below. Both azimuthal and radial anisotropies show a stratification of anisotropy at depth, corresponding to different physical processes. These results suggest that the Afar hotspot has a different and

  15. Seismological observations at the Northern Andean region of Colombia: Evidence for a shallowly subducting Caribbean Slab and an extensional regime in the upper plate

    Science.gov (United States)

    Monsalve, G.; Cardona, A.; Yarce, J.; Alvira, D.; Poveda, E.

    2013-05-01

    A number of seismological observations, among which we can mention teleseismic travel time residuals, P to S receiver functions and Pn velocity quantification, suggest a clear distinction between the seismic structure of the crust and uppermost mantle between the plains on the Caribbean coast of Colombia and the mountains at the Northern Andean region. Absolute and relative travel time residuals indicate the presence of a seismically fast material in the upper mantle beneath northern Colombia; preliminary results of Pn studies show a region of relatively slow Pn velocities (between 7.8 and 7.9 km/s) underneath the Caribbean coast, contrasting with values greater than 8 km/s beneath the Central and Western cordilleras of Colombia, and the Pacific coast; receiver functions suggest a significantly thinner crust beneath the Caribbean coast, with a crustal thickness between 25 and 30 km, than beneath the Northern Andean zone at the cordilleras of Colombia, where it exceeds 40 km and reaches about 57 km at the location of Bogota. Besides the obviuos discrepancies that appear in response to different topography, we think that the seismological observations are a consequence of the presence of two very distinct slab segments beneath Colombia and contrasting behaviors of the upper plate, which correspond to Caribbean and Nazca subductions. Our seismic observations can be explained by a shallowly subducting Caribbean Plate, in the absence of an asthenospheric wedge, that steepens at about the location of the Bucaramanga nest, and a thinned continental crust that reflects an extensional component linked to oblique convergence of the Caribbean, which contrasts with the crustal thickening in the Andean Cordillera linked to crustal shortening and Nazca plate subuction. These new data are consistent with the idea of of a relatively warm Nazca slab of Neogene age which seems to have a relatively frontal convergence, and a colder, more buoyant Caribbean slab which represents an

  16. 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

  17. Suitability of selected bioindicators of atmospheric pollution in the industrialised region of Ostrava, Upper Silesia, Czech Republic.

    Science.gov (United States)

    Francová, Anna; Chrastný, Vladislav; Šillerová, Hana; Kocourková, Jana; Komárek, Michael

    2017-08-29

    This study is a continuation of our preceding research identifying suitable environmental samples for the tracing of atmospheric pollution in industrial areas. Three additional types of environmental samples were used to characterise contamination sources in the industrial area of Ostrava city, Czech Republic. The region is known for its extensive metallurgical and mining activities. Fingerprinting of stable Pb isotopes was applied to distinguish individual sources of anthropogenic Pb. A wide range of 206 Pb/ 207 Pb ratios was observed in the investigated samples: 206 Pb/ 207 Pb = 1.168-1.198 in mosses; 206 Pb/ 207 Pb = 1.167-1.215 in soils and 206 Pb/ 207 Pb = 1.158-1.184 in tree cores. Black and brown coal combustion, as well as metallurgical activities, is the two main sources of pollution in the area. Fossil fuel burning in industry and households seems to be a stronger source of Pb emissions than from the metallurgical industry. Concentration analyses of tree rings showed that a significant increase in As concentrations occurred between 1999 and 2016 (from 0.38 mg kg -1 to 13.8 mg kg -1 ). This shift corresponds to the use of brown coal from Bílina, Czech Republic, with an increased As concentration. The burning of low-quality fuels in households remains a problem in the area, as small ground sources have a greater influence on the air quality than do industrial sources.

  18. A Damping Grid Strapdown Inertial Navigation System Based on a Kalman Filter for Ships in Polar Regions.

    Science.gov (United States)

    Huang, Weiquan; Fang, Tao; Luo, Li; Zhao, Lin; Che, Fengzhu

    2017-07-03

    The grid strapdown inertial navigation system (SINS) used in polar navigation also includes three kinds of periodic oscillation errors as common SINS are based on a geographic coordinate system. Aiming ships which have the external information to conduct a system reset regularly, suppressing the Schuler periodic oscillation is an effective way to enhance navigation accuracy. The Kalman filter based on the grid SINS error model which applies to the ship is established in this paper. The errors of grid-level attitude angles can be accurately estimated when the external velocity contains constant error, and then correcting the errors of the grid-level attitude angles through feedback correction can effectively dampen the Schuler periodic oscillation. The simulation results show that with the aid of external reference velocity, the proposed external level damping algorithm based on the Kalman filter can suppress the Schuler periodic oscillation effectively. Compared with the traditional external level damping algorithm based on the damping network, the algorithm proposed in this paper can reduce the overshoot errors when the state of grid SINS is switched from the non-damping state to the damping state, and this effectively improves the navigation accuracy of the system.

  19. Snow nitrate photolysis in polar regions and the mid-latitudes: Impact on boundary layer chemistry and implications for ice core records

    Science.gov (United States)

    Zatko, Maria C.

    The formation and recycling of nitrogen oxides (NOx=NO+NO 2) associated with snow nitrate photolysis has important implications for air quality and the preservation of nitrate in ice core records. This dissertation examines snow nitrate photolysis in polar and mid-latitude regions using field and laboratory based observations combined with snow chemistry column models and a global chemical transport model to explore the impacts of snow nitrate photolysis on boundary layer chemistry and the preservation of nitrate in polar ice cores. Chapter 1 describes how a global chemical transport model is used to calculate the photolysis-driven flux and redistribution of nitrogen across Antarctica, and Chapter 2 presents similar work for Greenland. Snow-sourced NOx is most dependent on the quantum yield for nitrate photolysis as well as the concentration of photolabile nitrate and light-absorbing impurities (e.g., black carbon, dust, organics) in snow. Model-calculated fluxes of snow-sourced NOx are similar in magnitude in Antarctica (0.5--7.8x108 molec cm-2 s -1) and Greenland (0.1--6.4x108 molec cm-2 s-1) because both nitrate and light-absorbing impurity concentrations in snow are higher (by factors of 2 and 10, respectively) in Greenland. Snow nitrate photolysis influences boundary layer chemistry and ice-core nitrate preservation less in Greenland compared to Antarctica largely due to Greenland's proximity to NOx-source regions. Chapter 3 describes how a snow chemistry column model combined with chemistry and optical measurements from the Uintah Basin Winter Ozone Study (UBWOS) 2014 is used to calculate snow-sourced NOx in eastern Utah. Daily-averaged fluxes of snow-sourced NOx (2.9x10 7--1.3x108 molec cm-2 s-1) are similar in magnitude to polar snow-sourced NO x fluxes, but are only minor components of the Uintah Basin boundary layer NOx budget and can be neglected when developing ozone reduction strategies for the region. Chapter 4 presents chemical and optical

  20. Geological analysis and petrographic training Tarata in careers (Upper Paleozoic)-test paleoclimatic interpretation in the light of the glacial episode devono-carboniferous (Arlit region, northern Niger)

    International Nuclear Information System (INIS)

    El Hamet, Mai Ousmane

    1983-01-01

    I - Lower Carboniferous glacial Designed west of the Air (northern Niger), it consists mainly of coarse sandstone with few pebbles scattered or polygenic conglomerate matrix abundant silty-clay sandstone. The ice structures, such as eskers, kames and Pingo are very well represented, but are smaller. The glacial facies are characterized by rapid lateral variations and fall into a narrow submeridional. The small extension of these facies and the position of this region at about 50 degrees south latitude in the Carboniferous period Devono-lead to believe that these phenomena related to valley glaciers mountain, but not necessarily requiring very high altitude at this latitude. II - Formation of Tarat:1-Stratigraphy. The sedimentological and petrographic study of tarat in the quarries in the region SOMAIR Arlit shows that this training has three distinct lithostratigraphic units separated by erosive surfaces of discontinuities with a major tarat located between the middle and upper Tarat . Biostratigraphy made from pollen analysis and paleobotanical studies confirm that major lithologic discontinuity between the deposition of Lower Carboniferous and Upper Permian those with a gap in the Upper Carboniferous and Lower Permian, it will be specified by further studies.2-Paleoclimatology. The new observations in the same career and the existence of glacial phenomena mentioned above before submitting the formation of tarat, led to consider the latter assuming a palaeoenvironment periglacial hypothesis that, in light periglacial seems to reject. Indeed, many characters observed (solifluction, grooves and ridges possible, relatively fresh feldspar) can also be observed in temperate and cold at that time, the region was located approximately 40 degrees south latitude.3-Volcanism.The existence of volcanism contemporaneous with deposition of Tarat was highlighted on one hand with the study of elements vitroclastiques, other hand with the cluster analysis of zircon, the zirconium

  1. Comparison of muscle and joint pressure-pain thresholds in patients with complex regional pain syndrome and upper limb pain of other origin.

    Science.gov (United States)

    Mainka, Tina; Bischoff, Florian S; Baron, Ralf; Krumova, Elena K; Nicolas, Volkmar; Pennekamp, Werner; Treede, Rolf-Detlef; Vollert, Jan; Westermann, Andrea; Maier, Christoph

    2014-03-01

    Pain localized in the deep tissues occurs frequently in complex regional pain syndrome (CRPS). In addition, hyperalgesia to blunt pressure over muscles is common in CRPS, but it often appears in limb pain of other origin as well. Considering that 3-phase bone scintigraphy (TPBS) reveals periarticular enhanced bone metabolism in CRPS, joint-associated hyperalgesia to blunt pressure might be a more specific finding than hyperalgesia over muscles. In 34 patients with upper limb pain (18 CRPS, 16 non-CRPS; diagnosed in accordance to the Budapest criteria) and in 18 healthy controls, pressure-pain thresholds (PPT) were assessed bilaterally over the thenar (PPTThenar), the metacarpophalangeal (PPTMCP), and the proximal interphalangeal (PPTPIP) joints using a pressure algometer (Somedic, Sweden). Beforehand, all patients had received TPBS for diagnostic purposes independently of the study. Region-of-interest (ROI) ratios (mineralization phase) for the MCP and PIP, excluding fracture sites, were correlated with the PPT. In CRPS, all ROI ratios were significantly increased and all PPT of the affected hand were decreased compared to non-CRPS (PPTThenar: 243±150kPa vs 358±197kPa, PPTMCP: 80±67kPa vs 159±93kPa, PPTPIP: 80±56kPa vs 184±110kPa; PPain. Published by Elsevier B.V. All rights reserved.

  2. Wireless peripheral nerve stimulation for complex regional pain syndrome type I of the upper extremity: a case illustration introducing a novel technology.

    Science.gov (United States)

    Herschkowitz, Daniel; Kubias, Jana

    2018-04-13

    Complex regional pain syndrome (CRPS) is a debilitating painful disorder, cryptic in its pathophysiology and refractory condition with limited therapeutic options. Type I CRPS with its variable relationship to trauma has often no discernible fractures or nerve injuries and remains enigmatic in its response to conservative treatment as well as the other limited interventional therapies. Neuromodulation in the form of spinal cord and dorsal root ganglion stimulation (SCS, DRGS) has shown encouraging results, especially of causalgia or CRPS I of lower extremities. Upper extremity CRPS I is far more difficult. To report a case of upper extremity CRPS I treated by wireless peripheral nerve stimulation (WPNS) for its unique features and minimally invasive technique. The system does not involve implantation of battery or its connections. A 47 year old female patient presented with refractory CRPS I following a blunt trauma to her right forearm. As interventional treatment in the form of local anesthetics (Anesthesia of peripheral branches of radial nerve) and combined infusions of ketamine/lidocaine failed to provide any significant relief she opted for WPNS treatment. Based on the topographic distribution, two electrodes (Stimwave Leads: FR4A-RCV-A0 with tines, Generation 1 and FR4A-RCV-B0 with tines, Generation 1), were placed along the course of radial and median nerves under ultrasonography monitoring and guided by intraoperative stimulation. This procedure did not involve implantation of extension cables or the power source. At a frequency of 60 Hz and 300 μs the stimulation induced paresthesia along the distribution of the nerves. Therapeutic relief was observed with high frequency (HF) stimulation (HF 10 kHz/32 μs, 2.0 mA) reducing her pain from a visual analogue scale (VAS) score of 7-4 postoperatively. Three HF stimulations programs were provided at the time of discharge, as she improved in her sensory impairment to touch, pressure and temperature at her first

  3. Assessment of impact of mass movements on the upper Tayyah valley's bridge along Shear escarpment highway, Asir region (Saudi Arabia) using remote sensing data and field investigation

    Science.gov (United States)

    Youssef, A. M.; Al-Kathery, M.; Pradhan, B.

    2015-01-01

    Escarpment highways, roads and mountainous areas in Saudi Arabia are facing landslide hazards that are frequently occurring from time to time causing considerable damage to these areas. Shear escarpment highway is located in the north of the Abha city. It is the most important escarpment highway in the area, where all the light and heavy trucks and vehicle used it as the only corridor that connects the coastal areas in the western part of the Saudi Arabia with the Asir and Najran Regions. More than 10 000 heavy trucks and vehicles use this highway every day. In the upper portion of Tayyah valley of Shear escarpment highway, there are several landslide and erosion potential zones that affect the bridges between tunnel 7 and 8 along the Shear escarpment Highway. In this study, different types of landslides and erosion problems were considered to access their impacts on the upper Tayyah valley's bridge along Shear escarpment highway using remote sensing data and field investigation. These landslides and erosion problems have a negative impact on this section of the highway. Results indicate that the areas above the highway and bridge level between bridge 7 and 8 have different landslides including planar, circular, rockfall failures and debris flows. In addition, running water through the gullies cause different erosional (scour) features between and surrounding the bridge piles and culverts. A detailed landslides and erosion features map was created based on intensive field investigation (geological, geomorphological, and structural analysis), and interpretation of Landsat image 15 m and high resolution satellite image (QuickBird 0.61 m), shuttle radar topography mission (SRTM 90 m), geological and topographic maps. The landslides and erosion problems could exhibit serious problems that affect the stability of the bridge. Different mitigation and remediation strategies have been suggested to these critical sites to minimize and/or avoid these problems in the future.

  4. 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.

  5. 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...

  6. Plasma polarization spectroscopy. History and future prospects

    International Nuclear Information System (INIS)

    Fujimoto, Takashi

    2002-01-01

    An intuitive account is given of the polarized emission line of atoms and ions, both classically and quantum mechanically. Polarization is a result of the population imbalance among the magnetic sublevels, or of the alignment, in the upper level. The history of Plasma Polarization Spectroscopy (PPS) is reviewed. Various polarization phenomena are divided into three classes. For each of the classes, typical experiments undertaken so far are reviewed. The advantages, limitations, and challenges regarding PPS are discussed. (author)

  7. The impact of Faraday effects on polarized black hole images of Sagittarius A*.

    Science.gov (United States)

    Jiménez-Rosales, Alejandra; Dexter, Jason

    2018-05-01

    We study model images and polarization maps of Sagittarius A* at 230 GHz. We post-process GRMHD simulations and perform a fully relativistic radiative transfer calculation of the emitted synchrotron radiation to obtain polarized images for a range of mass accretion rates and electron temperatures. At low accretion rates, the polarization map traces the underlying toroidal magnetic field geometry. At high accretion rates, we find that Faraday rotation internal to the emission region can depolarize and scramble the map. We measure the net linear polarization fraction and find that high accretion rate "jet-disc" models are heavily depolarized and are therefore disfavoured. We show how Event Horizon Telescope measurements of the polarized "correlation length" over the image provide a model-independent upper limit on the strength of these Faraday effects, and constrain plasma properties like the electron temperature and magnetic field strength.

  8. Lifetime and production rate of NOx in the upper stratosphere and lower mesosphere in the polar spring/summer after the solar proton event in October–November 2003

    Directory of Open Access Journals (Sweden)

    F. Friederich

    2013-03-01

    Full Text Available We present altitude-dependent lifetimes of NOx, determined with MIPAS/ENVISAT (the Michelson Interferometer for Passive Atmospheric Sounding/the European Environment Satellite, for the Southern polar region after the solar proton event in October–November 2003. Between 50° S and 90° S and decreasing in altitude they range from about two days at 64 km to about 20 days at 44 km. The lifetimes are controlled by transport, mixing and photochemistry. We infer estimates of dynamical lifetimes by comparison of the observed decay to photochemical lifetimes calculated with the SLIMCAT 3-D Model. Photochemical loss contributes to the observed NOx depletion by 0.1% at 44 km, increasing with altitude to 45% at 64 km. In addition, we show the correlation of modelled ionization rates and observed NOx densities under consideration of the determined lifetimes of NOx, and calculate altitude-dependent effective production rates of NOx due to ionization. For that we compare ionization rates of the AIMOS data base with the MIPAS measurements from 15 October–31 December 2003. We derive effective NOx-production rates to be applied to the AIMOS ionization rates which range from about 0.2 NOx-molecules per ion pair at 44 km to 0.7 NOx-molecules per ion pair at 62 km. These effective production rates are considerably lower than predicted by box model simulations which could hint at an overestimation of the modelled ionization rates.

  9. South Polar Polygons

    Science.gov (United States)

    2005-01-01

    4 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a polgyon-cracked surface, into which deep, somewhat kidney-bean-shaped pits have formed. These are landscapes of the martian south polar residual cap. This view was captured during May 2005. Location near: 86.9oS, 5.1oW Image width: 1.5 km (0.9 mi) Illumination from: upper left Season Southern Spring

  10. Rare earth elements in fly ashes created during the coal burning process in certain coal-fired power plants operating in Poland - Upper Silesian Industrial Region

    International Nuclear Information System (INIS)

    Smolka-Danielowska, Danuta

    2010-01-01

    The subject of the study covered volatile ashes created during hard coal burning process in ash furnaces, in power plants operating in the Upper Silesian Industrial Region, Southern Poland. Coal-fired power plants are furnished with dust extracting devices, electro precipitators, with 99-99.6% combustion gas extracting efficiency. Activity concentrations ofTh-232, Ra-226, K-40, Ac-228, U-235 and U-238 were measured with gamma-ray spectrometer. Concentrations of selected rare soil elements (La, Ce, Nd, Sm, Y, Gd, Th, U) were analysed by means of instrumental neutron activation analysis (INAA). Mineral phases of individual ash particles were identified with the use of scanning electron microscope equipped with EDS attachment. Laser granulometric analyses were executed with the use of Analyssette analyser. The activity of the investigated fly-ash samples is several times higher than that of the bituminous coal samples; in the coal, the activities are: 226Ra - 85.4 Bq kg -1 , 40 K-689 Bq kg -1 , 232Th - 100.8 Bq kg -1 , 235U-13.5 Bq kg -1 , 238U-50 Bq kg -1 and 228Ac - 82.4 Bq kg -1 .

  11. A uranium-bearing coalificated wood remain from the Upper Carboniferous uranium ore deposit in the Baden-Baden region of the Black Forest

    International Nuclear Information System (INIS)

    Kirchheimer, F.

    1981-01-01

    From the 1973 discovered Upper Carboniferous uranium ore sandstone deposit in the Baden-Baden region (Black Forest) a uranium-bearing coalificated wood remain derived, probably the relic of a Cordaites-trunk. The chemical determinated whole uranium content of this amounts about to 40 wght.-%. Pitchblende of the collomorphic type is embedded in the vitrinite of the fossil and imitates the nearly destroyed former wood-structure. The aggregates of this mineral, surrounded by zones of contact, consist of at least two modifications of different reflectance and hardness. Radiometric analyses reveale a different disturbed radioactive equilibrium, which indicated partly loss and re-enrichment of the uranium-content in recent time. A part of the fossil is completely mineralized by pitchblende of high reflectance and associated galena. For this paragenesis the radiometric investigations proved an approached equilibrium of radioactive substances. Therefore it is to be estimated, that the pitchblende is not alterated substantially, in contrast to the embeddings in the vitrinite, rich in little reflecting and soft nasturanium. The inhomogenic mineralization of the highly coalificated fossil, also to recognise microscopically, is set in relation to the controverse genetic interpretation of the deposit. Final remarks are concerned to other uranium-enriched fossils, especially remains of bones of different origin and age. (orig.) [de

  12. Rare earth elements in fly ashes created during the coal burning process in certain coal-fired power plants operating in Poland - Upper Silesian Industrial Region.

    Science.gov (United States)

    Smolka-Danielowska, Danuta

    2010-11-01

    The subject of the study covered volatile ashes created during hard coal burning process in ash furnaces, in power plants operating in the Upper Silesian Industrial Region, Southern Poland. Coal-fired power plants are furnished with dust extracting devices, electro precipitators, with 99-99.6% combustion gas extracting efficiency. Activity concentrations ofTh-232, Ra-226, K-40, Ac-228, U-235 and U-238 were measured with gamma-ray spectrometer. Concentrations of selected rare soil elements (La, Ce, Nd, Sm, Y, Gd, Th, U) were analysed by means of instrumental neutron activation analysis (INAA). Mineral phases of individual ash particles were identified with the use of scanning electron microscope equipped with EDS attachment. Laser granulometric analyses were executed with the use of Analyssette analyser. The activity of the investigated fly-ash samples is several times higher than that of the bituminous coal samples; in the coal, the activities are: 226Ra - 85.4 Bq kg(-1), 40 K-689 Bq kg(-1), 232Th - 100.8 Bq kg(-1), 235U-13.5 Bq kg(-1), 238U-50 Bq kg(-1) and 228Ac - 82.4 Bq kg(-1).

  13. Complex Regional Pain Syndrome type I of the upper limb - treatment based on Stress Loading Program: a case study

    Directory of Open Access Journals (Sweden)

    Aline Sarturi Ponte

    2015-03-01

    Full Text Available The daily life of an individual suffering from Complex Regional Pain Syndrome type I (CPRS I becomes limited, because this syndrome causes signs and symptoms located in the affected limb, and may occur in other parts. From this premise, this study aims to present the contributions of Occupational Therapy and the Rehabilitation Stress Loading Program for a subject with CRPS I in the upper limb, attended by the Group of Pain from the University Hospital of Santa Maria (HUSM, Rio Grande do Sul state. This research is characterized as a case study, experimental, which deals with pre and post occupational therapy intervention. The instruments used for data collection were the protocols of Disabilities of the Arm, Shoulder and Hand (DASH, the International Classification of Disability, Functioning and Health (ICF, the Canadian Occupational Performance Measure (COPM, the Visual Analogue Scale, and goniometry (EVA. After assessment, the subject was exposed to the treatment of compressive active resistive exercises; after this treatment was completed, the subject was reassessed. It was observed that the treatment applied has contributed to the reduction of the pain and to the improvement in the Range of Motion (ROM of the subject. The use of the stress protocol and active compression contributed significantly to the reduction of pain, ADM gain and occupational performance improvement.

  14. Airborne differential absorption lidar for water vapour measurements in the upper troposphere and lower stratosphere in the spectral region around 940 nm

    Energy Technology Data Exchange (ETDEWEB)

    Poberaj, G.

    2000-07-01

    Two all-solid-state laser systems were developed and studied in detail to optimise their performance for an airborne water vapour differential absorption lidar (DIAL). Their special features are high average output powers and excellent spectral properties in the 940-nm spectral region relevant for monitoring very low water vapour contents in the upper troposphere and lower stratosphere. One system is an injection-seeded pulsed Ti:sapphire ring laser with a spectral bandwidth of 105 MHz and an average power of 1.1 W. The other system is an injection-seeded optical parametric oscillator (OPO) in a ring configuration. Using KTP as nonlinear crystal, a signal output with a spectral bandwidth of 140 MHz and an average power of 1.2 W was achieved. Both systems, the Ti:sapphire ring laser and the KTP OPO, possess spectral purity values higher than 99%. The pump source for these systems is a frequency doubled diode-pumped Nd:YAG laser operating at a repetition rate of 100 Hz. The KTP OPO system has been used as a transmitter in a new airborne water vapour DIAL instrument. For the first time, measurements of two-dimensional water vapour distributions with a high vertical (500 m) and horizontal (20 km) resolution across several potential vorticity streamers were performed. Very low water vapour mixing ratios (10-50 ppmv) and strong gradients were observed in the tropopause region. The sensitivity of the DIAL instrument in the centre of a stratospheric intrusion ranges from 3% in the near field to 12% in the far field (4 km). The first comparison experiments with in situ measuring instruments show a good agreement. Considerable differences are found between DIAL measurements and data obtained from the ECMWF operational analyses and a mesoscale numerical model. (orig.)

  15. Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region

    Directory of Open Access Journals (Sweden)

    S. Oyama

    Full Text Available The field-aligned neutral oscillations in the F-region (altitudes between 165 and 275 km were compared using data obtained simultaneously with two independent instruments: the European Incoherent Scatter (EISCAT UHF radar and a scanning Fabry-Perot interferometer (FPI. During the night of February 8, 1997, simultaneous observations with these instruments were conducted at Tromsø, Norway. Theoretically, the field-aligned neutral wind velocity can be obtained from the field-aligned ion velocity and by diffusion and ambipolar diffusion velocities. We thus derived field-aligned neutral wind velocities from the plasma velocities in EISCAT radar data. They were compared with those observed with the FPI (λ=630.0 nm, which are assumed to be weighted height averages of the actual neutral wind. The weighting function is the normalized height dependent emission rate. We used two model weighting functions to derive the neutral wind from EISCAT data. One was that the neutral wind velocity observed with the FPI is velocity integrated over the entire emission layer and multiplied by the theoretical normalized emission rate. The other was that the neutral wind velocity observed with the FPI corresponds to the velocity only around an altitude where the emission rate has a peak. Differences between the two methods were identified, but not completely clarified. However, the neutral wind velocities from both instruments had peak-to-peak correspondences at oscillation periods of about 10–40 min, shorter than that for the momentum transfer from ions to neutrals, but longer than from neutrals to ions. The synchronizing motions in the neutral wind velocities suggest that the momentum transfer from neutrals to ions was thought to be dominant for the observed field-aligned oscillations rather than the transfer from ions to neutrals. It is concluded that during the observation, the plasma oscillations observed with the EISCAT radar at different altitudes

  16. Productive structure and production relations between polarized region by Londrina and the rest of Paraná in 2006

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Moretto

    2015-07-01

    Full Text Available This article had as objective estimate the sector linkages and the overflowing of the production multiplier between the North of Parana and the Rest of Parana, using the interregional input-output matrix for 1995. The main results showed that a agriculture and food processing sectors stood out in the productive structure of North of Parana State, comparing to the Rest of Parana State, as disseminators of inter-sector relations b the industrial structure of the Rest of Parana presented more diversification as compared to the North Region, showing less dependence on agriculture and food processing sectors for its dynamic; c the overflowing effect of the production multiplier in the direction Rest of Parana-North of Parana was 4,9%, whereas in the direction North of Parana-Rest of Parana it was 12%, revealing a greater dependency of the productive process of the North of Parana vis-a-vis the Rest of Parana; d the Rest of Parana, although more diversified in its productive structure, showed more dependence on the North of Parana as for the answer to the input requirements of the food processing sectors when facing growth in its final demand.

  17. Microbial and viral-like rhodopsins present in coastal marine sediments from four polar and subpolar regions

    Energy Technology Data Exchange (ETDEWEB)

    López, José L.; Golemba, Marcelo; Hernández, Edgardo; Lozada, Mariana; Dionisi, Hebe; Jansson, Janet K.; Carroll, Jolynn; Lundgren, Leif; Sjöling, Sara; Mac Cormack, Walter P.; Sobecky, Patricia

    2016-11-03

    Rhodopsins are broadly distributed. In this work, we analyzed 23 metagenomes corresponding to marine sediment samples from four regions that share cold climate conditions (Norway; Sweden; Argentina and Antarctica). In order to investigate the genes evolution of viral rhodopsins, an initial set of 6224 bacterial rhodopsin sequences according to COG5524 were retrieved from the 23 metagenomes. After selection by the presence of transmembrane domains and alignment, 123 viral (51) and non-viral (72) sequences (>50 amino acids) were finally included in further analysis. Viral rhodopsin genes were homologs of Phaeocystis globosa virus and Organic lake Phycodnavirus. Non-viral microbial rhodopsin genes were ascribed to Bacteroidetes, Planctomycetes, Firmicutes, Actinobacteria, Cyanobacteria, Proteobacteria, Deinococcus-Thermus and Cryptophyta and Fungi. A rescreening using Blastp, using as queries the viral sequences previously described, retrieved 30 sequences (>100 amino acids). Phylogeographic analysis revealed a geographical clustering of the sequences affiliated to the viral group. This clustering was not observed for the microbial non-viral sequences. The phylogenetic reconstruction allowed us to propose the existence of a putative ancestor of viral rhodopsin genes related to Actinobacteria and Chloroflexi. This is the first report about the existence of a phylogeographic association of the viral rhodopsin sequences from marine sediments.

  18. Meteor radar observations of vertically propagating low-frequency inertia-gravity waves near the southern polar mesopause region

    Science.gov (United States)

    Song, I.-S.; Lee, C.; Kim, J.-H.; Jee, G.; Kim, Y.-H.; Choi, H.-J.; Chun, H.-Y.; Kim, Y. H.

    2017-04-01

    Vertically propagating low-frequency inertia-gravity waves (IGWs) are retrieved from meteor radar winds observed at King Sejong Station (KSS: 62.22°S, 58.78°W), Antarctica. IGW horizontal winds extracted from temporal band-pass filtering in regular time-height bins show the frequent occurrence of IGWs with the downward phase progression and the counterclockwise rotation of their horizontal wind vectors with time (i.e., upward energy propagation) near the mesopause region throughout the whole year of 2014. The vertical wavelengths of the observed IGWs roughly range from 14 km to more than 20 km, which is consistent with previous observational studies on the mesospheric IGWs over Antarctica. Stokes parameters and rotary spectra computed from the hodographs of the IGW horizontal wind components reveal that the intrinsic frequencies of the upward propagating IGWs are |f|-3|f| with seasonal variations of the relative predominance between |f|-2|f| and 2|f|-3|f|, where f is the Coriolis parameter at KSS. The hodograph analysis also indicates that the N-S propagation is dominant in austral summer, while the NE-SW propagation is pronounced in austral winter. The propagation direction is discussed in relation to the generation of IGWs due to dynamical imbalances occurring in the tropospheric and stratospheric jet flow systems. Ray tracing results indicate that the N-S propagation in summer may be due to the jet flow systems roughly north of KSS and the NE-SW propagation in winter may be either the SW propagation from the jet flow systems northeast of KSS or the NE propagation (around the South Pole) from the south of Australia and Southern Indian and Pacific Oceans.

  19. 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)

  20. Measurement of K/sub NN/, K/sub SS/, K/sub SL/, and K/sub LL/ in polarized np → polarized pn at 800 MeV in the CEX region

    International Nuclear Information System (INIS)

    Ransome, R.D.; Hollas, C.L.; Riley, P.J.

    1980-01-01

    The spin transfer parameters K/sub NN/, K/sub SS/, K/sub SL/, and K/sub LL/ have been measured for np elastic scattering at 800 MeV between 165 0 and 180 0 c.m. The parameters K/sub NN/ and K/sub LL/ are in good agreement with the quasi-free reaction polarized pd → polarized npp at 180 0

  1. Application of polarization ellipse technique for analysis of ULF magnetic fields from two distant stations in Koyna-Warna seismoactive region, West India

    Directory of Open Access Journals (Sweden)

    F. Dudkin

    2010-07-01

    Full Text Available A new approach is developed to find the source azimuth of the ultra low frequency (ULF electromagnetic (EM signals believed to be emanating from well defined seismic zone. The method is test applied on magnetic data procured from the seismoactive region of Koyna-Warna, known for prolonged reservoir triggered seismicity. Extremely low-noise, high-sensitivity LEMI-30 search coil magnetometers were used to measure simultaneously the vector magnetic field in the frequency range 0.001–32 Hz at two stations, the one located within and another ~100 km away from the seismic active zone. During the observation campaign extending from 15 March to 30 June 2006 two earthquakes (EQs of magnitude (ML>4 occurred, which are searched for the presence of precursory EM signals.

    Comparison of polarization ellipses (PE parameters formed by the magnetic field components at the measurement stations, in select frequency bands, allows discrimination of seismo-EM signals from the natural background ULF signals of magnetospheric/ionospheric origin. The magnetic field components corresponding to spectral bands dominated by seismo-EM fields define the PE plane which at any instant contains the source of the EM fields. Intersection lines of such defined PE planes for distant observation stations clutter in to the source region. Approximating the magnetic-dipole configuration for the source, the magnetic field components along the intersection lines suggest that azimuth of the EM source align in the NNW-SSE direction. This direction well coincides with the orientation of nodal plane of normal fault plane mechanism for the two largest EQs recorded during the campaign. More significantly the correspondence of this direction with the tectonic controlled trend in local seismicity, it has been surmised that high pressure fluid flow along the fault that facilitate EQs in the region may also be the source mechanism for EM fields by electrokinetic effect.

  2. Vacuum ultraviolet spectropolarimeter design for precise polarization measurements.

    Science.gov (United States)

    Narukage, Noriyuki; Auchère, Frédéric; Ishikawa, Ryohko; Kano, Ryouhei; Tsuneta, Saku; Winebarger, Amy R; Kobayashi, Ken

    2015-03-10

    Precise polarization measurements in the vacuum ultraviolet (VUV) region provide a new means for inferring weak magnetic fields in the upper atmosphere of the Sun and stars. We propose a VUV spectropolarimeter design ideally suited for this purpose. This design is proposed and adopted for the NASA-JAXA chromospheric lyman-alpha spectropolarimeter (CLASP), which will record the linear polarization (Stokes Q and U) of the hydrogen Lyman-α line (121.567 nm) profile. The expected degree of polarization is on the order of 0.1%. Our spectropolarimeter has two optically symmetric channels to simultaneously measure orthogonal linear polarization states with a single concave diffraction grating that serves both as the spectral dispersion element and beam splitter. This design has a minimal number of reflective components with a high VUV throughput. Consequently, these design features allow us to minimize the polarization errors caused by possible time variation of the VUV flux during the polarization modulation and by statistical photon noise.

  3. CMB polarization at large angular scales: Data analysis of the POLAR experiment

    International Nuclear Information System (INIS)

    O'Dell, Christopher W.; Keating, Brian G.; Oliveira-Costa, Angelica de; Tegmark, Max; Timbie, Peter T.

    2003-01-01

    The coming flood of cosmic microwave background (CMB) polarization experiments, spurred by the recent detection of CMB polarization by the DASI and WMAP instruments, will be confronted by many new analysis tasks specific to polarization. For the analysis of CMB polarization data sets, the devil is truly in the details. With this in mind, we present details of the data analysis for the POLAR experiment, which recently led to the tightest upper limits on the polarization of the cosmic microwave background radiation at large angular scales. We discuss the data selection process, map-making algorithms, offset removal, and likelihood analysis which were used to find upper limits on the polarization. Stated using the modern convention for reporting CMB Stokes parameters, these limits are 5.0 μK on both E- and B-type polarization at 95% confidence. Finally, we discuss simulations used to test our analysis techniques and to probe the fundamental limitations of the experiment

  4. Polarization developments

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist

  5. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ON RHIC SPIN PHYSICS III AND IV, POLARIZED PARTONS AT HIGH Q2 REGION, AUGUST 3, 2000 AT BNL, OCTOBER 14, 2000 AT KYOTO UNIVERSITY.

    Energy Technology Data Exchange (ETDEWEB)

    BUNCE, G.; VIGDOR, S.

    2001-03-15

    International workshop on II Polarized Partons at High Q2 region 11 was held at the Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto, Japan on October 13-14, 2000, as a satellite of the international conference ''SPIN 2000'' (Osaka, Japan, October 16-21,2000). This workshop was supported by RIKEN (The Institute of Physical and Chemical Research) and by Yukawa Institute. The scientific program was focused on the upcoming polarized collider RHIC. The workshop was also an annual meeting of RHIC Spin Collaboration (RSC). The number of participants was 55, including 28 foreign visitors and 8 foreign-resident Japanese participants, reflecting the international nature of the RHIC spin program. At the workshop there were 25 oral presentations in four sessions, (1) RHIC Spin Commissioning, (2) Polarized Partons, Present and Future, (3) New Ideas on Polarization Phenomena, (4) Strategy for the Coming Spin Running. In (1) the successful polarized proton commissioning and the readiness of the accelerator for the physics program impressed us. In (2) and (3) active discussions were made on the new structure function to be firstly measured at RHIC, and several new theoretical ideas were presented. In session (4) we have established a plan for the beam time requirement toward the first collision of polarized protons. These proceedings include the transparencies presented at the workshop. The discussion on ''Strategy for the Coming Spin Running'' was summarized by the chairman of the session, S. Vigdor and G. Bunce.

  6. Detecting Precontact Anthropogenic Microtopographic Features in a Forested Landscape with Lidar: A Case Study from the Upper Great Lakes Region, AD 1000-1600.

    Science.gov (United States)

    Howey, Meghan C L; Sullivan, Franklin B; Tallant, Jason; Kopple, Robert Vande; Palace, Michael W

    2016-01-01

    Forested settings present challenges for understanding the full extent of past human landscape modifications. Field-based archaeological reconnaissance in forests is low-efficiency and most remote sensing techniques are of limited utility, and together, this means many past sites and features in forests are unknown. Archaeologists have increasingly used light detection and ranging (lidar), a remote sensing tool that uses pulses of light to measure reflecting surfaces at high spatial resolution, to address these limitations. Archaeology studies using lidar have made significant progress identifying permanent structures built by large-scale complex agriculturalist societies. Largely unaccounted for, however, are numerous small and more practical modifications of landscapes by smaller-scale societies. Here we show these may also be detectable with lidar by identifying remnants of food storage pits (cache pits) created by mobile hunter-gatherers in the upper Great Lakes during Late Precontact (ca. AD 1000-1600) that now only exist as subtle microtopographic features. Years of intensive field survey identified 69 cache pit groups between two inland lakes in northern Michigan, almost all of which were located within ~500 m of a lakeshore. Applying a novel series of image processing techniques and statistical analyses to a high spatial resolution DTM we created from commercial-grade lidar, our detection routine identified 139 high potential cache pit clusters. These included most of the previously known clusters as well as several unknown clusters located >1500 m from either lakeshore, much further from lakeshores than all previously identified cultural sites. Food storage is understood to have emerged regionally as a risk-buffering strategy after AD 1000 but our results indicate the current record of hunter-gatherer cache pit food storage is markedly incomplete and this practice and its associated impact on the landscape may be greater than anticipated. Our study also

  7. Endocrine disrupting alkylphenolic chemicals and other contaminants in wastewater treatment plant effluents, urban streams, and fish in the Great Lakes and Upper Mississippi River Regions

    Science.gov (United States)

    Barber, Larry B.; Loyo-Rosales, Jorge E.; Rice, Clifford P.; Minarik, Thomas A.; Oskouie, Ali K.

    2015-01-01

    Urban streams are an integral part of the municipal water cycle and provide a point of discharge for wastewater treatment plant (WWTP) effluents, allowing additional attenuation through dilution and transformation processes, as well as a conduit for transporting contaminants to downstream water supplies. Domestic and commercial activities dispose of wastes down-the-drain, resulting in wastewater containing complex chemical mixtures that are only partially removed during treatment. A key issue associated with WWTP effluent discharge into streams is the potential to cause endocrine disruption in fish. This study provides a long-term (1999-2009) evaluation of the occurrence of alkylphenolic endocrine disrupting chemicals (EDCs) and other contaminants discharged from WWTPs into streams in the Great Lakes and Upper Mississippi River Regions (Indiana, Illinois, Michigan, Minnesota, and Ohio). The Greater Metropolitan Chicago Area Waterways, Illinois, were evaluated to determine contaminant concentrations in the major WWTP effluents and receiving streams, and assess the behavior of EDCs from their sources within the sewer collection system, through the major treatment unit processes at a WWTP, to their persistence and transport in the receiving stream. Water samples were analyzed for alkylphenolic EDCs and other contaminants, including 4-nonylphenol (NP), 4-nonylphenolpolyethoxylates (NPEO), 4-nonylphenolethoxycarboxylic acids (NPEC), 4-tert-octylphenol (OP), 4-tert-octylphenolpolyethoxylates (OPEO), bisphenol A, triclosan, ethylenediaminetetraacetic acid (EDTA), and trace elements. All of the compounds were detected in all of the WWTP effluents, with EDTA and NPEC having the greatest concentrations. The compounds also were detected in the WWTP effluent dominated rivers. Multiple fish species were collected from river and lake sites and analyzed for NP, NPEO, NPEC, OP, and OPEO. Whole-body fish tissue analysis indicated widespread occurrence of alkylphenolic compounds

  8. Inspecting the transformation of Roman settlements in the Upper Potenza Valley (Marche region across Late Antiquity and into the Early Medieval era

    Directory of Open Access Journals (Sweden)

    Francesca Carboni

    2015-12-01

    Full Text Available The following analysis shows the changes occurred in the settlement patterns in the upper Potenza river valley (MC, Marche region during the transition period between Late Antiquity and Early Middle Ages. This analysis is mainly based on the results of a geoarchaeological project, which has been carried out by a team from Ghent University since 2000. The review of the pottery collected during the fi eld survey has allowed for a better defined chronology of the last phase of occupation of the rural sites identifi ed in the sample zone, located within an intermediate basin between the Umbria-Marche Apennines and a lateral dorsal ridge, in areas dominated by the hilltops of Monte Primo and Monte Castel Santa Maria. For some of these sites, it is now possible to ascertain a continuity of life up to the end of the seventh century and further into the Middle Ages. La presente analisi illustra le trasformazioni delle modalità insediative avvenute nel periodo di transizione fra la tarda antichità e il medioevo nell’alta valle del fi ume Potenza (MC, Marche. Essa si basa sui risultati del progetto condotto con metodo geo-archeologico da un gruppo di ricerca dell’Università di Ghent, dal 2000. La revisione del materiale ceramico raccolto nel corso delle ricognizioni ha consentito di defi nire meglio le ultime fasi di occupazione dei siti rurali identifi cati nella zona campione in questione, posizionata all’interno del bacino intramontano posto fra l’Appennino umbro-marchigiano e una dorsale montuosa laterale, dominata dalle cime del Monte Primo e del Monte Santa Maria. Per alcuni di questi siti è stato, infatti, possibile accertare una continuità di occupazione estesa fi no al VII secolo e oltre, in età medievale.

  9. Endocrine disrupting alkylphenolic chemicals and other contaminants in wastewater treatment plant effluents, urban streams, and fish in the Great Lakes and Upper Mississippi River Regions.

    Science.gov (United States)

    Barber, Larry B; Loyo-Rosales, Jorge E; Rice, Clifford P; Minarik, Thomas A; Oskouie, Ali K

    2015-06-01

    Urban streams are an integral part of the municipal water cycle and provide a point of discharge for wastewater treatment plant (WWTP) effluents, allowing additional attenuation through dilution and transformation processes, as well as a conduit for transporting contaminants to downstream water supplies. Domestic and commercial activities dispose of wastes down-the-drain, resulting in wastewater containing complex chemical mixtures that are only partially removed during treatment. A key issue associated with WWTP effluent discharge into streams is the potential to cause endocrine disruption in fish. This study provides a long-term (1999-2009) evaluation of the occurrence of alkylphenolic endocrine disrupting chemicals (EDCs) and other contaminants discharged from WWTPs into streams in the Great Lakes and Upper Mississippi River Regions (Indiana, Illinois, Michigan, Minnesota, and Ohio). The Greater Metropolitan Chicago Area Waterways, Illinois, were evaluated to determine contaminant concentrations in the major WWTP effluents and receiving streams, and assess the behavior of EDCs from their sources within the sewer collection system, through the major treatment unit processes at a WWTP, to their persistence and transport in the receiving stream. Water samples were analyzed for alkylphenolic EDCs and other contaminants, including 4-nonylphenol (NP), 4-nonylphenolpolyethoxylates (NPEO), 4-nonylphenolethoxycarboxylic acids (NPEC), 4-tert-octylphenol (OP), 4-tert-octylphenolpolyethoxylates (OPEO), bisphenol A, triclosan, ethylenediaminetetraacetic acid (EDTA), and trace elements. All of the compounds were detected in all of the WWTP effluents, with EDTA and NPEC having the greatest concentrations. The compounds also were detected in the WWTP effluent dominated rivers. Multiple fish species were collected from river and lake sites and analyzed for NP, NPEO, NPEC, OP, and OPEO. Whole-body fish tissue analysis indicated widespread occurrence of alkylphenolic compounds

  10. Regional stratospheric warmings in the Pacific-Western Canada (PWC sector during winter 2004/2005: implications for temperatures, winds, chemical constituents and the characterization of the Polar vortex

    Directory of Open Access Journals (Sweden)

    A. H. Manson

    2008-11-01

    Full Text Available The vortex during winter 2004/2005 was interesting for several reasons. It has been described as "cold" stratospherically, with relatively strong westerly winds. Losses of ozone until the final warming in March were considerable, and comparable to the cold 1999–2000 winter. There were also modest warming events, indicated by peaks in 10 hPa zonal mean temperatures at high latitudes, near 1 January and 1 February. Events associated with a significant regional stratospheric warming in the Pacific-Western Canada (PWC sector then began and peaked toward the end of February, providing strong longitudinal variations in dynamical characteristics (Chshyolkova et al., 2007; hereafter C07. The associated disturbed vortex of 25 February was displaced from the pole and either elongated (upper or split into two cyclonic centres (lower.

    Observations from Microwave Limb Sounder (MLS on Aura are used here to study the thermal characteristics of the stratosphere in the Canadian-US (253° E and Scandinavian-Europe (16° E sectors. Undisturbed high latitude stratopause (55 km zonal mean temperatures during the mid-winter (December–February reached 270 K, warmer than empirical-models such as CIRA-86, suggesting that seasonal polar warming due to dynamical influences affects the high altitude stratosphere as well as the mesosphere. There were also significant stratopause differences between Scandinavia and Canada during the warming events of 1 January and 1 February, with higher temperatures near 275 K at 16° E. During the 25 February "PWC" event a warming occurred at low and middle stratospheric heights (10–30 km: 220 K at 253° E and the stratopause cooled; while over Scandinavia-Europe the stratosphere below ~30 km was relatively cold at 195 K and the stratopause became even warmer (>295 K and lower (~45 km. The zonal winds followed the associated temperature gradients so that the vertical and latitudinal gradients of the winds differed strongly

  11. Regional stratospheric warmings in the Pacific-Western Canada (PWC sector during winter 2004/2005: implications for temperatures, winds, chemical constituents and the characterization of the Polar vortex

    Directory of Open Access Journals (Sweden)

    A. H. Manson

    2008-11-01

    Full Text Available The vortex during winter 2004/2005 was interesting for several reasons. It has been described as "cold" stratospherically, with relatively strong westerly winds. Losses of ozone until the final warming in March were considerable, and comparable to the cold 1999–2000 winter. There were also modest warming events, indicated by peaks in 10 hPa zonal mean temperatures at high latitudes, near 1 January and 1 February. Events associated with a significant regional stratospheric warming in the Pacific-Western Canada (PWC sector then began and peaked toward the end of February, providing strong longitudinal variations in dynamical characteristics (Chshyolkova et al., 2007; hereafter C07. The associated disturbed vortex of 25 February was displaced from the pole and either elongated (upper or split into two cyclonic centres (lower. Observations from Microwave Limb Sounder (MLS on Aura are used here to study the thermal characteristics of the stratosphere in the Canadian-US (253° E and Scandinavian-Europe (16° E sectors. Undisturbed high latitude stratopause (55 km zonal mean temperatures during the mid-winter (December–February reached 270 K, warmer than empirical-models such as CIRA-86, suggesting that seasonal polar warming due to dynamical influences affects the high altitude stratosphere as well as the mesosphere. There were also significant stratopause differences between Scandinavia and Canada during the warming events of 1 January and 1 February, with higher temperatures near 275 K at 16° E. During the 25 February "PWC" event a warming occurred at low and middle stratospheric heights (10–30 km: 220 K at 253° E and the stratopause cooled; while over Scandinavia-Europe the stratosphere below ~30 km was relatively cold at 195 K and the stratopause became even warmer (>295 K and lower (~45 km. The zonal winds followed the associated temperature gradients so that the vertical and latitudinal gradients of the winds differed strongly between

  12. Occupational and environmental mercury exposure among small-scale gold miners in the Talensi-Nabdam District of Ghana's Upper East region.

    Science.gov (United States)

    Paruchuri, Yasaswi; Siuniak, Amanda; Johnson, Nicole; Levin, Elena; Mitchell, Katherine; Goodrich, Jaclyn M; Renne, Elisha P; Basu, Niladri

    2010-11-15

    Mercury use in small-scale gold mining is ubiquitous across Ghana but little is known about the extent to which such activities have contaminated community residents and miners. Here, occupational exposures to elemental mercury (via urine sampling) and dietary exposures to methylmercury (via hair sampling) were assessed among 120 participants recruited from a mining community located in the Talensi-Nabdam District of Ghana's Upper East region during summer 2009. More than one-fifth of the participants had moderately high levels of urinary mercury (>10μg/L) and 5% had urine mercury levels that exceeded the WHO guideline value of 50μg/L. When participants were stratified according to occupation, those active in the mining industry had the highest mercury levels. Specifically, individuals that burned amalgam had urine mercury levels (median: 43.8μg/L; mean ± SD: 171.1±296.5μg/L; n=5) significantly higher than median values measured in mechanical operators (11.6μg/L, n=4), concession managers/owners (5.6μg/L, n=11), excavators that blast and chisel ore (4.9μg/L, n=33), individuals that sift and grind crushed ore (2.2μg/L, n=47), support workers (0.5μg/L, n=14), and those with no role in the mining sector (2.5μg/L, n=6). There was a significant positive Spearman correlation between fish consumption and hair mercury levels (r=0.30) but not with urine mercury (r=0.18) though further studies are needed to document which types of fish are consumed as well as portion sizes. Given that 200,000 people in Ghana are involved in the small-scale gold mining industry and that the numbers are expected to grow in Ghana and many other regions of the world, elucidating mercury exposure pathways in such communities is important to help shape policies and behaviors that may minimize health risks. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Occupational and environmental mercury exposure among small-scale gold miners in the Talensi-Nabdam District of Ghana’s Upper East region

    Science.gov (United States)

    Paruchuri, Yasaswi; Siuniak, Amanda; Johnson, Nicole; Levin, Elena; Mitchell, Katherine; Goodrich, Jaclyn M.; Renne, Elisha P.; Basu, Niladri

    2014-01-01

    Mercury use in small-scale gold mining is ubiquitous across Ghana but little is known about the extent to which such activities have contaminated community residents and miners. Here, occupational exposures to elemental mercury (via urine sampling) and dietary exposures to methylmercury (via hair sampling) were assessed among 120 participants recruited from a mining community located in the Talensi-Nabdam District of Ghana’s Upper East region during summer 2009. More than one-fifth of the participants had moderately high levels of urinary mercury (>10 µg/L) and 5% had urine mercury levels that exceeded the WHO guideline value of 50 µg/L. When participants were stratified according to occupation, those active in the mining industry had the highest mercury levels. Specifically, individuals that burned amalgam had urine mercury levels (median: 43.8 µg/L; mean ± SD: 171.1 ± 296.5 µg/L; n=5) significantly higher than median values measured in mechanical operators (11.6 µg/L, n=4), concession managers/owners (5.6 µg/L, n=11), excavators that blast and chisel ore (4.9 µg/L, n=33), individuals that sift and grind crushed ore (2.2 µg/L, n=47), support workers (0.5 µg/L, n=14), and those with no role in the mining sector (2.5 µg/L, n=6). There was a significant positive spearman correlation between fish consumption and hair mercury levels (r = 0.30) but not with urine mercury (r = 0.18) though further studies are needed to document which types of fish are consumed as well as portion sizes. Given that 200,000 people in Ghana are involved in the small-scale gold mining industry and that the numbers are expected to grow in Ghana and many other regions of the world, elucidating mercury exposure pathways in such communities is important to help shape policies and behaviors that may minimize health risks. PMID:20875913

  14. Detection of polar vapours

    International Nuclear Information System (INIS)

    Blyth, D.A.

    1980-01-01

    Apparatus for monitoring for polar vapours in a gas consists of (i) a body member defining a passage through which a continuous stream of the gas passes; (ii) an ionising source associated with a region of the passage such that ionization of the gas stream takes place substantially only within the region and also any polar vapour molecules present therein will react with the gas formed to generate ion clusters; and (iii) an electrode for collecting ions carried by the gas stream, the electrode being positioned in the passage downstream of the region and separated from the region by a sufficient distance to ensure that no substantial number of the gas ions formed in said region remains in the gas stream at the collector electrode whilst ensuring that a substantial proportion of the ion clusters formed in the region does remain in the gas stream at the collector electrode. (author)

  15. On the relations between proton influx and D-region electron densities during the polar-cap absorption event of 28-29 October 2003

    Directory of Open Access Journals (Sweden)

    J. K. Hargreaves

    2005-11-01

    Full Text Available Observations by incoherent-scatter radar have been applied to explore relationships between the fluxes of incident protons and the resulting D-region electron densities during a polar-cap radio-absorption event. Using proton flux data from a GOES geosynchronous satellite, the energy band having the greatest influence at a selected height is estimated by a process of trial and error, and empirical relationships are defined. The height profiles of the effective recombination coefficient are determined for day and night, and the transition over the evening twilight is investigated for the height range 60-70 km.

    The results show that the day-night change is confined to heights below 80 km, night-time values at the lower levels being consistent with a balance between negative ions and electrons controlled by 3-body attachment and collisional detachment. The daytime results confirm that, contrary to the prediction of some chemical models, a square-law continuity equation may be strictly applied. It is confirmed that, as previously reported, the timing of the sunset change varies with altitude.

  16. On the relations between proton influx and D-region electron densities during the polar-cap absorption event of 28-29 October 2003

    Directory of Open Access Journals (Sweden)

    J. K. Hargreaves

    2005-11-01

    Full Text Available Observations by incoherent-scatter radar have been applied to explore relationships between the fluxes of incident protons and the resulting D-region electron densities during a polar-cap radio-absorption event. Using proton flux data from a GOES geosynchronous satellite, the energy band having the greatest influence at a selected height is estimated by a process of trial and error, and empirical relationships are defined. The height profiles of the effective recombination coefficient are determined for day and night, and the transition over the evening twilight is investigated for the height range 60-70 km. The results show that the day-night change is confined to heights below 80 km, night-time values at the lower levels being consistent with a balance between negative ions and electrons controlled by 3-body attachment and collisional detachment. The daytime results confirm that, contrary to the prediction of some chemical models, a square-law continuity equation may be strictly applied. It is confirmed that, as previously reported, the timing of the sunset change varies with altitude.

  17. Polarized Structure Function $\\sigma_{LT'}$ for $p({\\vec e},e'K^+)\\Lambda$ in the Nucleon Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Nasseripour, Rakhsha; Raue, Brian; Ambrozewicz, Pawel; Carman, Daniel; Amaryan, Moscov; Amaryan, Moskov; Anciant, Eric; Anghinolfi, Marco; Asavapibhop, Burin; Asryan, Gegham; Audit, Gerard; Auger, Thierry; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Beard, Kevin; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Casey, Liam; Cetina, Catalina; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Dennis, Lawrence; Deur, Alexandre; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dragovitsch, Peter; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girard, Pascal; Girod, Francois-Xavier; Goetz, John; Gothe, Ralf; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hu, Jicun; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Kim, Kui; Kim, Kyungmo; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; Lukashin, Konstantin; MacCormick, Marion; Manak, Joseph; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Peterson, Gerald; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Sayre, Donald; Schumacher, Reinhard; Serov, Vladimir; Shafi, Aziz; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Simionatto, Sebastio; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Taylor, Shawn; Tedeschi, David; Thoma, Ulrike; Thompson, Richard; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Wang,

    2008-06-01

    The first measurements of the polarized structure function $\\sigma_{LT'}$ for the reaction $p(\\vec e,e'K^+)\\Lambda$ in the nucleon resonance region are reported. Measurements are included from threshold up to $W$=2.05 GeV for central values of $Q^2$ of 0.65 and 1.00 GeV$^2$, and nearly the entire kaon center-of-mass angular range. $\\sigma_{LT'}$ is the imaginary part of the longitudinal-transverse response and is expected to be sensitive to interferences between competing intermediate s-channel resonances, as well as resonant and non-resonant processes. The results for $\\sigma_{LT'}$ are comparable in magnitude to previously reported results from CLAS for $\\sigma_{LT}$, the real part of the same response. An intriguing sign change in $\\sigma_{LT'}$ is observed in the high $Q^2$ data at $W\\approx 1.9$ GeV. Comparisons to several existing model predictions are shown.

  18. Atmospheric loss from the dayside open polar region and its dependence on geomagnetic activity: implications for atmospheric escape on evolutionary timescales

    Directory of Open Access Journals (Sweden)

    R. Slapak

    2017-06-01

    Full Text Available We have investigated the total O+ escape rate from the dayside open polar region and its dependence on geomagnetic activity, specifically Kp. Two different escape routes of magnetospheric plasma into the solar wind, the plasma mantle, and the high-latitude dayside magnetosheath have been investigated separately. The flux of O+ in the plasma mantle is sufficiently fast to subsequently escape further down the magnetotail passing the neutral point, and it is nearly 3 times larger than that in the dayside magnetosheath. The contribution from the plasma mantle route is estimated as  ∼ 3. 9 × 1024exp(0. 45 Kp [s−1] with a 1 to 2 order of magnitude range for a given geomagnetic activity condition. The extrapolation of this result, including escape via the dayside magnetosheath, indicates an average O+ escape of 3 × 1026 s−1 for the most extreme geomagnetic storms. Assuming that the range is mainly caused by the solar EUV level, which was also larger in the past, the average O+ escape could have reached 1027–28 s−1 a few billion years ago. Integration over time suggests a total oxygen escape from ancient times until the present roughly equal to the atmospheric oxygen content today.

  19. Spectro-polarimetric observation in UV with CLASP to probe the chromosphere and transition region

    Science.gov (United States)

    Kano, Ryouhei; Ishikawa, Ryohko; Winebarger, Amy R.; Auchère, Frédéric; Trujillo Bueno, Javier; Narukage, Noriyuki; Kobayashi, Ken; Bando, Takamasa; Katsukawa, Yukio; Kubo, Masahito; Ishikawa, Shin-Nosuke; Giono, Gabriel; Hara, Hirohisa; Suematsu, Yoshinori; Shimizu, Toshifumi; Sakao, Taro; Tsuneta, Saku; Ichimoto, Kiyoshi; Goto, Motoshi; Cirtain, Jonathan W.; De Pontieu, Bart; Casini, Roberto; Manso Sainz, Rafael; Asensio Ramos, Andres; Stepan, Jiri; Belluzzi, Luca; Carlsson, Mats

    2016-05-01

    The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a NASA sounding-rocket experiment that was performed in White Sands in the US on September 3, 2015. During its 5-minute ballistic flight, CLASP successfully made the first spectro-polarimetric observation in the Lyman-alpha line (121.57 nm) originating in the chromosphere and transition region. Since the Lyman-alpha polarization is sensitive to magnetic field of 10-100 G by the Hanle effect, we aim to infer the magnetic field information in such upper solar atmosphere with this experiment.The obtained CLASP data showed that the Lyman-alpha scattering polarization is about a few percent in the wings and the order of 0.1% in the core near the solar limb, as it had been theoretically predicted, and that both polarization signals have a conspicuous spatio-temporal variability. CLASP also observed another upper-chromospheric line, Si III (120.65 nm), whose critical field strength for the Hanle effect is 290 G, and showed a measurable scattering polarization of a few % in this line. The polarization properties of the Si III line could facilitate the interpretation of the scattering polarization observed in the Lyman-alpha line.In this presentation, we would like to show how the upper chromosphere and transition region are seen in the polarization of these UV lines and discuss the possible source of these complicated polarization signals.

  20. A discussion for the evolution model of Pb isotope of the upper mantle in western Yunnan and its interpretation to the lead isotopic compositions of the regional alkali-rich porphyries and their related rocks

    International Nuclear Information System (INIS)

    Wu Kaixing; Hu Ruizhong; Bi Xianwu; Zhang Qian; Peng Jiantang

    2003-01-01

    Thirty Pb isotope data of the upper mantle in the area of western Yunnan have the similar trends with the Stacey-Kramers' two stage model growth curves but apparently deviate from it on the lead isotope composition programs, which may suggest Pb isotope of the upper mantle in the area of western Yunnan might have two stage evolution history though not fit very well to the Stacey-Kramers' two stage model growth curves. In this paper, a two-stage growth curves which can better fit the Pb isotope data was constructed based on the lead isotope data of the upper mantle in western Yunnan and the principle that Stacey and Kramers constructed the two-stage model and a reasonable interpretation was given to the lead isotopic compositions of the regional alkali-rich porphyries and their related rocks using the model. (authors)

  1. Constraining the thickness of polar ice deposits on Mercury using the Mercury Laser Altimeter and small craters in permanently shadowed regions

    Science.gov (United States)

    Deutsch, Ariel N.; Head, James W.; Chabot, Nancy L.; Neumann, Gregory A.

    2018-05-01

    Radar-bright deposits at the poles of Mercury are located in permanently shadowed regions, which provide thermally stable environments for hosting and retaining water ice on the surface or in the near subsurface for geologic timescales. While the areal distribution of these radar-bright deposits is well characterized, their thickness, and thus their total mass and volume, remain poorly constrained. Here we derive thickness estimates for selected water-ice deposits using small, simple craters visible within the permanently shadowed, radar-bright deposits. We examine two endmember scenarios: in Case I, these craters predate the emplacement of the ice, and in Case II, these craters postdate the emplacement of the ice. In Case I, we find the difference between estimated depths of the original unfilled craters and the measured depths of the craters to find the estimated infill of material. The average estimated infilled material for 9 craters assumed to be overlain with water ice is ∼ 41-14+30 m, where 1-σ standard error of the mean is reported as uncertainty. Reported uncertainties are for statistical errors only. Additional systematic uncertainty may stem from georeferencing the images and topographic datasets, from the radial accuracy of the altimeter measurements, or from assumptions in our models including (1) ice is flat in the bowl-shaped crater and (2) there is negligible ice at the crater rims. In Case II, we derive crater excavation depths to investigate the thickness of the ice layer that may have been penetrated by the impact. While the absence of excavated regolith associated with the small craters observed suggests that impacts generally do not penetrate through the ice deposit, the spatial resolution and complex illumination geometry of images may limit the observations. Therefore, it is not possible to conclude whether the small craters in this study penetrate through the ice deposit, and thus Case II does not provide a constraint on the ice thickness

  2. Polarization holography

    DEFF Research Database (Denmark)

    Nikolova, L.; Ramanujam, P.S.

    Current research into holography is concerned with applications in optically storing, retrieving, and processing information. Polarization holography has many unique properties compared to conventional holography. It gives results in high efficiency, achromaticity, and special polarization...... properties. This books reviews the research carried out in this field over the last 15 years. The authors provide basic concepts in polarization and the propagation of light through anisotropic materials, before presenting a sound theoretical basis for polarization holography. The fabrication...... and characterization of azobenzene based materials, which remain the most efficient for the purpose, is described in detail. This is followed by a description of other materials that are used in polarization holography. An in-depth description of various applications, including display holography and optical storage...

  3. Unsustainability of water resources in the Upper Laja River Basin, Mexico: Social-hydrology interactions in a regional overexploited aquifer with increasing concentrations of fluoride, arsenic and sodium

    Science.gov (United States)

    Ortega, A.

    2013-05-01

    The Upper Laja River Basin, also known as the Independence Basin (IB), with an area of 7,000 km2 and a population near to 500,000 inhabitants is part of the regional Lerma-Chapala Basin in Central Mexico. Groundwater is the main source for drinking water supply, agriculture and industrial uses. Total groundwater extraction is in the order of 1,000 million of m3/a, through near to 3,000 wells in the basin, from which about 85% is for agriculture production, mainly for exportation. Historical hydrologic information in the basin showed the existence of numerous streams, rivers and lakes within the catchments in addition to thousands of springs in the discharge area. At present there is not permanent runoff in the main river and most of the springs and associated ecosystems have disappeared. Water table in the aquifer is between 100 and 200 m depth with decreasing rates between 2 m/a and 10 m/a, while 60 years ago water tables was near ground surface. Dissolved concentration of arsenic and fluoride in groundwater is increasing with time, causing severe health effects in rural villages and more recently in the main urban centers. Increasing concentration of sodium is affecting soil productivity and plant grow, where several hectares of land are been abandoned. There are several pieces of evidence that show the unsustainability of water resources in the IB creating complex social-hydrology interactions: Human actions are impairing the long-term renewability of freshwater stocks and flows. Basic water requirement are not been guaranteed to all inhabitants to maintain human health, neither to restore nor to maintain the remaining ecosystems. Water quality does not meet certain minimum standards in most of the basin. Water-planning and decision making are not democratic, the COTAS, a representation of water users is controlled by farmers with political power; therefore, limiting the participation of other parties and fostering direct participation of affected interests

  4. Polarization parameters. sigma. , T, and P for the reaction. gamma. p. -->. p. pi. /sup 0/ in the region of the first resonance

    Energy Technology Data Exchange (ETDEWEB)

    Belyaev, A.A.; Get' man, V.A.; Gorbenko, V.G.; Gushchin, V.A.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Lukhanin, A.A.; Rubashkin, A.L.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.

    1982-03-01

    We report an experimental study of the ..sigma.., T, and P parameters of the cross section for the reaction ..gamma..p..-->..p..pi../sup 0/ for photon energies 300, 320, 350, 380, 400, 420 MeV in the range of pion emission angles 60--135/sup 0/ c.m.s. The technique of a double polarization experiment with use of linearly polarized photons and a polarized proton target is described. The experimental results are compared with the predictions of theoretical analyses.

  5. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-09-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  6. Polar bears at risk

    Energy Technology Data Exchange (ETDEWEB)

    Norris, S.; Rosentrater, L.; Eid, P.M. [WWF International Arctic Programme, Oslo (Norway)

    2002-05-01

    Polar bears, the world's largest terrestrial carnivore, spend much of their lives on the arctic sea ice. This is where they hunt and move between feeding, denning, and resting areas. The world population, estimated at 22,000 bears, is made up of 20 relatively distinct populations varying in size from a few hundred to a few thousand animals. About 60 per cent of all polar bears are found in Canada. In general, the status of this species is stable, although there are pronounced differences between populations. Reductions in the extent and thickness of sea ice has lead the IUCN Polar Bear Specialist Group to describe climate change as one of the major threats facing polar bears today. Though the long-term effects of climate change will vary in different areas of the Arctic, impacts on the condition and reproductive success of polar bears and their prey are likely to be negative. Longer ice-free periods resulting from earlier break-up of sea ice in the spring and later formation in the fall is already impacting polar bears in the southern portions of their range. In Canada's Hudson Bay, for example, bears hunt on the ice through the winter and into early summer, after which the ice melts completely, forcing bears ashore to fast on stored fat until freeze-up in the fall. The time bears have on the ice to hunt and build up their body condition is cut short when the ice melts early. Studies from Hudson Bay show that for every week earlier that ice break-up occurs, bears will come ashore 10 kg lighter and in poorer condition. It is likely that populations of polar bears dividing their time between land and sea will be severely reduced and local extinctions may occur as greenhouse gas emissions continue to rise and sea ice melts. Expected changes in regional weather patterns will also impact polar bears. Rain in the late winter can cause maternity dens to collapse before females and cubs have departed, thus exposing occupants to the elements and to predators. Such

  7. Ionic polarization

    International Nuclear Information System (INIS)

    Mahan, G.D.

    1992-01-01

    Ferroelectricity occurs in many different kinds of materials. Many of the technologically important solids, which are ferroelectric, can be classified as ionic. Any microscopic theory of ferroelectricity must contain a description of local polarization forces. We have collaborated in the development of a theory of ionic polarization which is quite successful. Its basic assumption is that the polarization is derived from the properties of the individual ions. We have applied this theory successfully to diverse subjects as linear and nonlinear optical response, phonon dispersion, and piezoelectricity. We have developed numerical methods using the local Density approximation to calculate the multipole polarizabilities of ions when subject to various fields. We have also developed methods of calculating the nonlinear hyperpolarizability, and showed that it can be used to explain light scattering experiments. This paper elaborates on this polarization theory

  8. Review of polarized ammonium target

    International Nuclear Information System (INIS)

    Matsuda, Tatsuo

    1987-01-01

    Recently, ammonia (NH 3 ) and deutron ammonia (ND 3 ), instead of conventional alcohol substances, have been used more frequently as a polarized target substance for experiments of polarization at high energy regions. This article reviews major features of the polarized (deutron) ammonia targets. The dynamic nuclear polarization (DNT) method is widely used in high energy polarization experiments. While only a low polarization degree of hydrogen nucleus of 1.7 percent can be obtained by the Brute force method, DNP can produce polarization as high as ∼ 90 percent (2.5 T, ∼ 200 mK). In 1979, ammonia was irradiated with radiations to form NH 2 free radicals, resulting in the achievement of a high polarization degree of greater than 90 percent (hydrogen). Since then, ammonia and deutron ammonia have increasingly been replacing alcohols including butanol. Irradiation of a target substance with radiations destroys the structure of the substance, leading to a decrease in polarization degree. However, ammonia produces unpaired electrons as a result of irradiation, allowing it to be highly resistant to radiation. This report also present some study results, including observations on effects of radiation on the polarization degree of a target, effects of annealing, and polarization of 14 N. A process for producing an ammonia target is also described. (Nogami, K.)

  9. Polarization experiments

    International Nuclear Information System (INIS)

    Halzen, F.

    1977-02-01

    In a theoretical review of polarization experiments two important points are emphasized: (a) their versatility and their relevance to a large variety of aspects of hadron physics (tests of basic symmetries; a probe of strong interaction dynamics; a tool for hadron spectroscopy); (b) the wealth of experimental data on polarization parameters in pp and np scattering in the Regge language and in the diffraction language. (author)

  10. Change in the F region structure of a polar ionosphere at the change of the Y component sighn of the interplanetary magnetic field. Svalgaard-Mansurov effect in the ionosphere

    International Nuclear Information System (INIS)

    Gal'perin, Yu.I.; Zosimova, A.G.; Larina, T.N.; Mozhaev, A.M.; Osipov, N.K.; Ponomarev, Yu.N.

    1980-01-01

    Model calculations of the planetary picture of the polar ionosphere characteristics taking into account modern models of magnetospheric convection are carried out. The results of direct measurements of the lateral component of the convection rate in the day polar cusp region obtained by the ''Kosmos-184'' satellite in 1967 indicative of rotation of the zonal convection component direction with tha change of the Bsub(y) component sign of the interplanetary magnetic field (IMF). It is shown that the change of the IMF Bsub(y) sign and the following change of the convection picture in the polar cap must cause a quick (10 3 s) change of the planetary picture of the polar ionosphere characteristics in the F region peak and higher, i.e. ''the Svalgard-Mansurov ionospheric effect''. The amplitude of the variations and their character are defined by the relation of the solar and auroral ionization, and, therefore, they strongly depend on the universal time, season and auroral activity, that hampers comparison of the calculations with the experiment. The experimental data obtained from satellites and indicative of the reality of the described ionospheric Bsub(y) effect are presented. Thus, the data of many years on the ionospheric measurements from the Earth and satellites parallel with the magnetic measurements can be used to specify parameters describing the magnetospheric convection picture [ru

  11. Temperature oscillations in the upper thermocline region- A case study on internal waves off Kalpeni Island in the southern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Charyulu, R.J.K.; Sarma, Y.V.B.; Sarma, M.S.S.; Rao, L.V.G.

    characteristics of the temperature oscillations. The power spectra of temperature fluctuations at 11 depths in the upper thermocline from 80 to 100 m with 2 m interval, were computed for studying the short period internal waves. Power spectra density was higher...

  12. Optimal geophysical complex and methods for investigation of peleogene and upper cretaceous deposits in search and exploratory wells in the northern areas of Tumen region

    International Nuclear Information System (INIS)

    Nelepchenko, O.M.; Akhiyarov, V.Kh.

    1975-01-01

    A number of geophysical studies of the Paleogene and upper Cretaceous deposits in prospecting and exploration boreholes in the northern part of the Tyumen field are described. The studies include, besides the essential ones, neutron logging with thermal neutrons (NKT-50), infrared logging, and lateral logging

  13. Postradiation motor neuron syndrome of the upper cervical region - a manifestation of the combined effect of cranial irradiation and intrathecal chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tan, S.V.; Pye, I.F. (Leicester Royal Infirmary (United Kingdom))

    1991-05-01

    The authors present a brief case report of neurogenic amyotropy apparently resulting from damage to the anterior horn cells of the upper cervical cord and lower brainstem during cranial irradiation which occurred as part of the patient's treatment for acute leukaemia. (Author).

  14. Polarization measurement for internal polarized gaseous targets

    International Nuclear Information System (INIS)

    Ye Zhenyu; Ye Yunxiu; Lv Haijiang; Mao Yajun

    2004-01-01

    The authors present an introduction to internal polarized gaseous targets, polarization method, polarization measurement method and procedure. To get the total nuclear polarization of hydrogen atoms (including the polarization of the recombined hydrogen molecules) in the target cell, authors have measured the parameters relating to atomic polarization and polarized hydrogen atoms and molecules. The total polarization of the target during our measurement is P T =0.853 ± 0.036. (authors)

  15. Sources of polarized neutrons

    International Nuclear Information System (INIS)

    Walter, L.

    1983-01-01

    Various sources of polarized neutrons are reviewed. Monoenergetic source produced with unpolarized or polarized beams, white sources of polarized neutrons, production by transmissions through polarized hydrogen targets and polarized thermal neutronsare discussed, with appropriate applications included. (U.K.)

  16. The polar mesosphere

    International Nuclear Information System (INIS)

    Morris, Ray; Murphy, Damian

    2008-01-01

    The mesosphere region, which lies at the edge of space, contains the coldest layer of the Earth's atmosphere, with summer temperatures as low as minus 130 °C. In this extreme environment ice aerosol layers have appeared since the dawn of industrialization—whose existence may arguably be linked to human influence—on yet another layer of the Earth's fragile atmosphere. Ground-based and space-based experiments conducted in the Arctic and Antarctic during the International Polar Year (IPY) aim to address limitations in our knowledge and to advance our understanding of thermal and dynamical processes at play in the polar mesosphere

  17. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  18. Correlations of mesospheric winds with subtle motion of the Arctic polar vortex

    Directory of Open Access Journals (Sweden)

    Y. Bhattacharya

    2010-01-01

    Full Text Available This paper investigates the relationship between high latitude upper mesospheric winds and the state of the stratospheric polar vortex in the absence of major sudden stratospheric warmings. A ground based Michelson Interferometer stationed at Resolute Bay (74°43' N, 94°58' W in the Canadian High Arctic is used to measure mesopause region neutral winds using the hydroxyl (OH Meinel-band airglow emission (central altitude of ~85 km. These observed winds are compared to analysis winds in the upper stratosphere during November and December of 1995 and 1996; years characterized as cold, stable polar vortex periods. Correlation of mesopause wind speeds with those from the upper stratosphere is found to be significant for the 1996 season when the polar vortex is subtly displaced off its initial location by a strong Aleutian High. These mesopause winds are observed to lead stratospheric winds by approximately two days with increasing (decreasing mesospheric winds predictive of decreasing (increasing stratospheric winds. No statistically significant correlations are found for the 1995 season when there is no such displacement of the polar vortex.

  19. Degree of polarization and source counts of faint radio sources from Stacking Polarized intensity

    International Nuclear Information System (INIS)

    Stil, J. M.; George, S. J.; Keller, B. W.; Taylor, A. R.

    2014-01-01

    We present stacking polarized intensity as a means to study the polarization of sources that are too faint to be detected individually in surveys of polarized radio sources. Stacking offers not only high sensitivity to the median signal of a class of radio sources, but also avoids a detection threshold in polarized intensity, and therefore an arbitrary exclusion of sources with a low percentage of polarization. Correction for polarization bias is done through a Monte Carlo analysis and tested on a simulated survey. We show that the nonlinear relation between the real polarized signal and the detected signal requires knowledge of the shape of the distribution of fractional polarization, which we constrain using the ratio of the upper quartile to the lower quartile of the distribution of stacked polarized intensities. Stacking polarized intensity for NRAO VLA Sky Survey (NVSS) sources down to the detection limit in Stokes I, we find a gradual increase in median fractional polarization that is consistent with a trend that was noticed before for bright NVSS sources, but is much more gradual than found by previous deep surveys of radio polarization. Consequently, the polarized radio source counts derived from our stacking experiment predict fewer polarized radio sources for future surveys with the Square Kilometre Array and its pathfinders.

  20. Effectiveness of a specific manual approach to the suboccipital region in patients with chronic mechanical neck pain and rotation deficit in the upper cervical spine: study protocol for a randomized controlled trial.

    Science.gov (United States)

    González Rueda, Vanessa; López de Celis, Carlos; Barra López, Martín Eusebio; Carrasco Uribarren, Andoni; Castillo Tomás, Sara; Hidalgo García, Cesar

    2017-09-05

    Mechanical neck pain is a highly prevalent problem in primary healthcare settings. Many of these patients have restricted mobility of the cervical spine. Several manual techniques have been recommended for restoring cervical mobility, but their effectiveness in these patients is unknown. The aim of the present study is to compare the effectiveness of two types of specific techniques of the upper neck region: the pressure maintained suboccipital inhibition technique (PMSIT) and the translatory dorsal glide mobilization (TDGM) C0-C1 technique, as adjuncts to a protocolized physiotherapy treatment of the neck region in subjects with chronic mechanical neck pain and rotation deficit in the upper cervical spine. A randomized, prospective, double-blind (patient and evaluator) clinical trial. The participants (n = 78) will be randomly distributed into three groups. The Control Group will receive a protocolized treatment for 3 weeks, the Mobilization Group will receive the same protocolized treatment and 6 sessions (2 per week) of the TDGM C0-C1 technique, and the Pressure Group will receive the same protocolized treatment and 6 sessions (2 per week) of the PMSIT technique. The intensity of pain (VAS), neck disability (NDI), the cervical range of motion (CROM), headache intensity (HIT-6) and the rating of clinical change (GROC scale) will be measured. The measurements will be performed at baseline, post-treatment and 3 months after the end of treatment, by the same physiotherapist blinded to the group assigned to the subject. We believe that an approach including manual treatment to upper cervical dysfunction will be more effective in these patients. Furthermore, the PMSIT technique acts mostly on the musculature, while the TDGM technique acts on the joint. We expect to clarify which component is more effective in improving the upper cervical mobility. ClinicalTrials.gov NCT02832232 . Registered on July 13th, 2016.

  1. Polarized protons at RHIC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1990-12-01

    The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

  2. Features of the low-frequency polarization response in the region of the ferroelectric phase transition in multiferroic TbMnO.sub.3./sub.

    Czech Academy of Sciences Publication Activity Database

    Trepakov, Vladimír; Kvyatkovskii, O.E.; Savinov, Maxim; Dejneka, Alexandr; Wang, X.; Cheong, S.W.

    2016-01-01

    Roč. 58, č. 10 (2016), s. 2021-2026 ISSN 1063-7834 Institutional support: RVO:68378271 Keywords : low-frequency * polarization response * ferroelectric, phase * transition * multiferroic * TbMnO 3 Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 0.860, year: 2016

  3. Three-dimensional Radiative Transfer Simulations of the Scattering Polarization of the Hydrogen Lyalpha Line in a Magnetohydrodynamic Model of the Chromosphere-Corona Transition Region

    Czech Academy of Sciences Publication Activity Database

    Štěpán, Jiří; Trujillo Bueno, J.; Leenaarts, J.; Carlsson, M.

    2015-01-01

    Roč. 803, č. 2 (2015), 65/1-65/15 ISSN 0004-637X R&D Projects: GA ČR GPP209/12/P741 Grant - others:EU(XE) COST action MP1104 Institutional support: RVO:67985815 Keywords : polarization * radiative transfer * scattering Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.909, year: 2015

  4. Polarization study

    International Nuclear Information System (INIS)

    Nurushev, S.B.

    1989-01-01

    Brief review is presented of the high energy polarization study including experimental data and the theoretical descriptions. The mostimportant proposals at the biggest accelerators and the crucial technical developments are also listed which may become a main-line of spin physics. 35 refs.; 10 figs.; 4 tabs

  5. Polar Stratigraphy

    Science.gov (United States)

    1999-01-01

    These three images were taken on three different orbits over the north polar cap in April 1999. Each shows a different part of the same ice-free trough. The left and right images are separated by a distance of more than 100 kilometers (62 miles). Note the similar layers in each image.

  6. Recent advance in polar seismology: Global impact of the International Polar Year

    Science.gov (United States)

    Kanao, Masaki; Zhao, Dapeng; Wiens, Douglas A.; Stutzmann, Éléonore

    2015-03-01

    The most exciting initiative for the recent polar studies was the International Polar Year (IPY) in 2007-2008. The IPY has witnessed a growing community of seismologists who have made considerable efforts to acquire high-quality data in polar regions. It also provided an excellent opportunity to make significant advances in seismic instrumentation of the polar regions to achieve scientific targets involving global issues. Taking these aspects into account, we organize and publish a special issue in Polar Science on the recent advance in polar seismology and cryoseismology as fruitful achievements of the IPY.

  7. Pliocene geomagnetic polarity epochs

    Science.gov (United States)

    Dalrymple, G.B.; Cox, A.; Doell, Richard R.; Gromme, C.S.

    1967-01-01

    A paleomagnetic and K-Ar dating study of 44 upper Miocene and Pliocene volcanic units from the western United States suggests that the frequency of reversals of the earth's magnetic field during Pliocene time may have been comparable with that of the last 3.6 m.y. Although the data are too limited to permit the formal naming of any new polarity epochs or events, four polarity transitions have been identified: the W10 R/N boundary at 3.7 ?? 0.1 m.y., the A12 N/R boundary at 4.9 ?? 0.1 m.y., the W32 N/R boundary at 9.0 ?? 0.2m.y., and the W36 R/N boundary at 10.8 ?? 0.3 - 1.0 m.y. The loss of absolute resolution of K-Ar dating in older rocks indicates that the use of well defined stratigraphic successions to identify and date polarity transitions will be important in the study of Pliocene and older reversals. ?? 1967.

  8. Regional scheme for the connection to the grid of renewable energies: for the Hauts-de-France region, for the Nord-Pas-de-Calais region, for the Picardy region, the Alsace region, the Aquitaine region, the Auvergne region, the Lower-Normandy region, the Burgundy region, the Brittany region, the Centre-Val-de-Loire region, the Champagne-Ardennes region, the Franche-Comte region, the Upper Normandy region, the Ile-de-France region, the Languedoc-Roussillon region, the Lorraine region, the Midi-Pyrenees region, the Provence-Alps-Cote d'Azur region, the Pays-de-la-Loire region, the Poitou-Charentes region, the Rhone-Alps region. Technical and financial status of the scheme implementation

    International Nuclear Information System (INIS)

    2017-01-01

    This document gathers reports related to all French regions. Each one addresses the elaboration of the concerned regional scheme of connection of renewable energies to the distribution network (French acronym: S3REnR) which aims at anticipating and planning evolutions of electrical networks which are necessary for the integration of renewable energies. Illustrated by maps, tables and graphs, these reports propose indications of energy production locations, an identification of planned works, a presentation of the concerned region, of its existing grid and projects, an overview of the scheme content (initial status, results of consultations, adopted strategies, planned works), and an overview of the scheme implementation status

  9. Juno/JEDI observations of 0.01 to >10 MeV energetic ions in the Jovian auroral regions: Anticipating a source for polar X-ray emission

    Science.gov (United States)

    Haggerty, D. K.; Mauk, B. H.; Paranicas, C. P.; Clark, G.; Kollmann, P.; Rymer, A. M.; Bolton, S. J.; Connerney, J. E. P.; Levin, S. M.

    2017-07-01

    After a successful orbit insertion, the Juno spacecraft completed its first 53.5 day orbit and entered a very low altitude perijove with the full scientific payload operational for the first time on 27 August 2016. The Jupiter Energetic particle Detector Instrument measured ions and electrons over the auroral regions and through closest approach, with ions measured from 0.01 to >10 MeV, depending on species. This report focuses on the composition of the energetic ions observed during the first perijove of the Juno mission. Of particular interest are the ions that precipitate from the magnetosphere onto the polar atmosphere and ions that are accelerated locally by Jupiter's powerful auroral processes. We report preliminary findings on the spatial variations, species, including energy and pitch angle distributions throughout the prime science region during the first orbit of the Juno mission. The prime motivation for this work was to examine the heavy ions that are thought to be responsible for the observed polar X-rays. Jupiter Energetic particle Detector Instrument (JEDI) did observe precipitating heavy ions with energies >10 MeV, but for this perijove the intensities were far below those needed to account for previously observed polar X-ray emissions. During this survey we also found an unusual signal of ions between oxygen and sulfur. We include here a report on what appears to be a transitory observation of magnesium, or possibly sodium, at MeV energies through closest approach.

  10. Lunar true polar wander inferred from polar hydrogen.

    Science.gov (United States)

    Siegler, M A; Miller, R S; Keane, J T; Laneuville, M; Paige, D A; Matsuyama, I; Lawrence, D J; Crotts, A; Poston, M J

    2016-03-24

    The earliest dynamic and thermal history of the Moon is not well understood. The hydrogen content of deposits near the lunar poles may yield insight into this history, because these deposits (which are probably composed of water ice) survive only if they remain in permanent shadow. If the orientation of the Moon has changed, then the locations of the shadowed regions will also have changed. The polar hydrogen deposits have been mapped by orbiting neutron spectrometers, and their observed spatial distribution does not match the expected distribution of water ice inferred from present-day lunar temperatures. This finding is in contrast to the distribution of volatiles observed in similar thermal environments at Mercury's poles. Here we show that polar hydrogen preserves evidence that the spin axis of the Moon has shifted: the hydrogen deposits are antipodal and displaced equally from each pole along opposite longitudes. From the direction and magnitude of the inferred reorientation, and from analysis of the moments of inertia of the Moon, we hypothesize that this change in the spin axis, known as true polar wander, was caused by a low-density thermal anomaly beneath the Procellarum region. Radiogenic heating within this region resulted in the bulk of lunar mare volcanism and altered the density structure of the Moon, changing its moments of inertia. This resulted in true polar wander consistent with the observed remnant polar hydrogen. This thermal anomaly still exists and, in part, controls the current orientation of the Moon. The Procellarum region was most geologically active early in lunar history, which implies that polar wander initiated billions of years ago and that a large portion of the measured polar hydrogen is ancient, recording early delivery of water to the inner Solar System. Our hypothesis provides an explanation for the antipodal distribution of lunar polar hydrogen, and connects polar volatiles to the geologic and geophysical evolution of the Moon

  11. Microfacies, Depositional environment and Sequence Stratigraphy of Upper Carboniferous- Lower Permian rocks from Ozbak-Kuh region (Zaladou Section, East Central Iran

    Directory of Open Access Journals (Sweden)

    Ali Ahmadi

    2016-01-01

    Full Text Available Zaladou section is located in Ozbak-Kuh mountains in the nourthen part of Tabas block and consist of shale, limy sandstone, limestone and dolomite. Continous relationship of Upper Carboniferous and Lower Permian deposits, is quite evident in Zaladou section. The lower boundry of this section is located on the Absheni formation of Sardar Group with disconformity surface, and upper boundry’s is covered by disconformity surface and bauxite horizon of Bagh-e-Vang formation. According to the lithological Characters and microscopic studies, tidal flat, lagoon, bar, tidal inlet and open marine sub-environment are identified for Zaladou section. Results of this study show that Zaladou section was deposited in silisiclastic-carbonate mix homoclinal ramp in late Carboniferous and in carbonate homoclinal ramp in early Permian. Field study, microfacies and analysis through the sequence led to recognition of main sequence surface, such as: sequence boundry, maximum flooding surface, marine flooding surface, system tracts and two depositional sequences.

  12. Study of Jupiter polarization properties

    International Nuclear Information System (INIS)

    Bolkvadze, O.R.

    1980-01-01

    Investigations into polarization properties of the Jupiter reflected light were carried on at the Abastumani astrophysical observatory in 1967, 1968 and 1969 in the four spectral ranges: 4000, 4800, 5400 and 6600 A deg. Data on light polarization in different parts of the Jupiter visible disk are given. Curves of dependence of the planet light polarization degree on a phase angle are plotted. It is shown that in the central part of the visible planet disk the polarization degree is low. Atmosphere is in a stable state in this part of Jupiter. Mean radius of particles of a cloud layer is equal to 0.26μ, and optical thickness of overcloud atmosphere tau=0.05. Height of transition boundary of the cloud layer into overcloud gas atmosphere changes from year to year at the edges of the equatorial zone. Optical thickness of overcloud atmosphere changes also with changing height of a transient layer. The polar Jupiter regions possess a high degree of polarization which depends on a latitude. Polarization increases monotonously with the latitude and over polar regions accepts a maximum value [ru

  13. Sulfur mass loading of the atmosphere from volcanic eruptions: Calibration of the ice core record on basis of sulfate aerosol deposition in polar regions from the 1982 El Chichon eruption

    Science.gov (United States)

    Sigurdsson, Haraldur; Laj, Paolo

    1990-01-01

    Major volcanic eruptions disperse large quantities of sulfur compound throughout the Earth's atmosphere. The sulfuric acid aerosols resulting from such eruptions are scavenged by snow within the polar regions and appear in polar ice cores as elevated acidity layers. Glacio-chemical studies of ice cores can, thus, provide a record of past volcanism, as well as the means for understanding the fate of volcanic sulfur in the atmosphere. The primary objectives of this project are to study the chemistry and physical properties of volcanic fallout in a Greenland Ice Core in order to evaluate the impact of the volcanic gases on the atmospheric chemistry and the total atmospheric mass of volcanic aerosols emitted by major volcanic eruptions. We propose to compare the ice core record to other atmospheric records performed during the last 10 years to investigate transport and deposition of volcanic materials.

  14. Study on the impact of sudden stratosphere warming in the upper mesosphere-lower thermosphere regions using satellite and HF radar measurements [Conference paper

    CSIR Research Space (South Africa)

    Mbatha, N

    2009-07-01

    Full Text Available Neutral atmosphere (including the MLT) and ionosphere are linked by energy and momentum transfer. Thus, this whole region forms a coupled system in which influences that originates at one height or in one region can have profound influence elsewhere...

  15. Nuclear Energy Center: upper St. Lawrence region. Part I. Siting. Part II. Fort Drum surrogate site, description and impact assessment. Part III. Dispersed sites impact assessment and comparison with the NEC

    Energy Technology Data Exchange (ETDEWEB)

    Merry, P.A.; Luner, C.; Hong, S.W.; Canham, H.O.; Boggs, J.F.; McCool, T.P.

    1976-12-01

    This report is one of many supporting documents used by the Nuclear Regulatory commission in the preparation of the Nuclear Energy Center Site Survey (NECSS) mandated by Congress. While the overall study focuses on the feasibility and practicability of nuclear energy centers (NECs), this report is directed towards choosing a suitable surrogate site in the upper St. Lawrence region of New York State, assessing the probable impacts associated with construction and operation of the NEC, and comparing these impacts with those associated with small dispersed nuclear power stations. The upper St. Lawrence region is surveyed to identify a specific site that might be suitable for a surrogate NEC. Several assumptions about the basic design of an NEC are delineated, and a general overview of the characteristics of the region is given. The Fort Drum Military Reservation is chosen as a suitable surrogate site. Fort Drum and the surrounding area are described in terms of land use and population patterns, terrestrial and aquatic ecology, water use and quality, meteorology, institutional framework, and socioeconomic structure. The impacts associated with NEC development are assessed. Then the impacts associated with smaller dispersed nuclear power stations located throughout New York State are assessed and compared with the impacts associated with the NEC. Finally, the impacts due to development of the transmission line networks associated with the NEC and with the dispersed power stations are assessed and compared.

  16. Geologic framework for the assessment of undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic-Lower Cretaceous Cotton Valley Group, U.S. Gulf of Mexico region

    Science.gov (United States)

    Eoff, Jennifer D.; Dubiel, Russell F.; Pearson, Ofori N.; Whidden, Katherine J.

    2015-01-01

    The U.S. Geological Survey (USGS) is assessing the undiscovered oil and gas resources in sandstone reservoirs of the Upper Jurassic–Lower Cretaceous Cotton Valley Group in onshore areas and State waters of the U.S. Gulf of Mexico region. The assessment is based on geologic elements of a total petroleum system. Four assessment units (AUs) are defined based on characterization of hydrocarbon source and reservoir rocks, seals, traps, and the geohistory of the hydrocarbon products. Strata in each AU share similar stratigraphic, structural, and hydrocarbon-charge histories.

  17. Observation of atomic oxygen O(1S) green-line emission in the summer polar upper mesosphere associated with high-energy (≥30 keV) electron precipitation during high-speed solar wind streams

    Science.gov (United States)

    Lee, Young-Sook; Kwak, Young-Sil; Kim, Kyung-Chan; Solheim, Brian; Lee, Regina; Lee, Jaejin

    2017-01-01

    The auroral green-line emission at 557.7 nm wavelength as arising from the atomic oxygen O(1S → 1D) transition typically peaks at an altitude of 100 km specifically in the nightside oval, induced by auroral electrons within an energy range of 100 eV-30 keV. Intense aurora is known as being suppressed by sunlight in summer daytime but usually occurs in low electrical background conductivity. However, in the present study in summer (July) sunlit condition, enhancements of O(1S) emission rates observed by using the Wind Imaging Interferometer/UARS were frequently observed at low altitudes below 90 km, where ice particles are created initially as subvisible and detected as polar mesosphere summer echoes, emerging to be an optical phenomenon of polar mesospheric clouds. The intense O(1S) emission occurring in summer exceeds those occurring in the daytime in other seasons both in occurrence and in intensity, frequently accompanied by occurrences of supersonic neutral velocity (300-1500 m s-1). In the mesosphere, ion motion is controlled by electric field and the momentum is transferred to neutrals. The intense O(1S) emission is well associated with high-energy electron precipitation as observed during an event of high-speed solar wind streams. Meanwhile, since the minimum occurrences of O(1S) emission and supersonic velocity are maintained even in the low precipitation flux, the mechanism responsible is not only related to high-energy electron precipitation but also presumably to the local conditions, including the composition of meteoric-charged ice particles and charge separation expected in extremely low temperatures (<150 K).

  18. Some polarization features of solar microwave bursts

    Energy Technology Data Exchange (ETDEWEB)

    Uralov, A M; Nefed' ev, V P [AN SSSR, Irkutsk. Sibirskij Inst. Zemnogo Magnetizma Ionosfery i Rasprostraneniya Radiovoln

    1977-01-01

    Consequences of the thermal microwave burst model proposed earlier have been considered. According to the model the centimeter burst is generated at the heat propagation to the upper atmosphere. The polarization features of the burst are explained: a change of the polarization sign in a frequency range, a rapid change of the polarization sign in the development of a burst at a fixed frequency, a lack of time coincidence of the moments of the burst maximum of the polarization and of the total flux. From the model the consequences are obtained, which are still not confirmed by experiment. An ordinary-type wave prevails in the burst radiation, in the course of which the polarization degree falls on the ascending branch of bursts development. At the change of the polarization sign at the fixed frequency prior to the sign change an ordinary-type wave should be present in excess and later an extreordinary type wave.

  19. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Depression Wetlands in the Upper Des Plaines River Basin

    National Research Council Canada - National Science Library

    Lin, Jeff P

    2006-01-01

    .... The HGM approach is a collection of concepts and methods used to develop functional indices to assess the capacity of a particular wetland to perform functions relative to similar wetlands in a region...

  20. Promoting Diversity Through Polar Interdisciplinary Coordinated Education (Polar ICE)

    Science.gov (United States)

    McDonnell, J. D.; Hotaling, L. A.; Garza, C.; Van Dyk, P. B.; Hunter-thomson, K. I.; Middendorf, J.; Daniel, A.; Matsumoto, G. I.; Schofield, O.

    2017-12-01

    Polar Interdisciplinary Coordinated Education (ICE) is an education and outreach program designed to provide public access to the Antarctic and Arctic regions through polar data and interactions with the scientists. The program provides multi-faceted science communication training for early career scientists that consist of a face-to face workshop and opportunities to apply these skills. The key components of the scientist training workshop include cultural competency training, deconstructing/decoding science for non-expert audiences, the art of telling science stories, and networking with members of the education and outreach community and reflecting on communication skills. Scientists partner with educators to provide professional development for K-12 educators and support for student research symposia. Polar ICE has initiated a Polar Literacy initiative that provides both a grounding in big ideas in polar science and science communication training designed to underscore the importance of the Polar Regions to the public while promoting interdisciplinary collaborations between scientists and educators. Our ultimate objective is to promote STEM identity through professional development of scientists and educators while developing career awareness of STEM pathways in Polar science.

  1. Sustaining observations in the polar oceans.

    Science.gov (United States)

    Abrahamsen, E P

    2014-09-28

    Polar oceans present a unique set of challenges to sustained observations. Sea ice cover restricts navigation for ships and autonomous measurement platforms alike, and icebergs present a hazard to instruments deployed in the upper ocean and in shelf seas. However, the important role of the poles in the global ocean circulation provides ample justification for sustained observations in these regions, both to monitor the rapid changes taking place, and to better understand climate processes in these traditionally poorly sampled areas. In the past, the vast majority of polar measurements took place in the summer. In recent years, novel techniques such as miniature CTD (conductivity-temperature-depth) tags carried by seals have provided an explosion in year-round measurements in areas largely inaccessible to ships, and, as ice avoidance is added to autonomous profiling floats and gliders, these promise to provide further enhancements to observing systems. In addition, remote sensing provides vital information about changes taking place in sea ice cover at both poles. To make these observations sustainable into the future, improved international coordination and collaboration is necessary to gain optimum utilization of observing networks. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  2. Volume distribution for particles between 3.5 to 2000 μm in the upper 200 m region of the South Pacific Gyre

    Directory of Open Access Journals (Sweden)

    L. Stemmann

    2008-03-01

    border of the SPG to the ultra-oligotrophy of the center in the upper 200 m depth. We expect large particles to play a major role in the trophic interaction in the upper waters of the South Pacific Gyre.

  3. Non-volant mammals from the Upper Paraná River Basin: a data set from a critical region for conservation in Brazil.

    Science.gov (United States)

    Gonçalves, Fernando; Hannibal, Wellington; Godoi, Mauricio N; Martins, Fernando I; Oliveira, Roniel F; Figueiredo, Valquiria V; Casella, Janaina; de Sá, Érica F G G

    2018-02-01

    The data set represents the first attempt at a large-scale inventory of non-volant mammals, with potential applications to performing macroecological studies, developing conservation strategies, and undertaking population and community ecology research, but also to evaluate the ecological consequences of fragmentation and defaunation. Our objectives for compiling these data were to summarize information about inventories of non-volant mammals in the critically important area of the Upper Paraná River Basin by focusing on species richness and index of frequency of occurrence and to identify gaps in knowledge regarding non-volant mammal communities in order to guide future sampling efforts. The data set comprises studies on communities of non-volant mammals from 52 locations covering more than 1,000 km 2 and comprises portion of four Brazilian states in the Upper Paraná River Basin. We listed 81 species of non-volant mammals distributed among 58 genera, 22 families, and 9 orders. Rodentia (28 species) was the richest order, followed by Carnivora (17 spp.) and Didelphimorphia (15 spp.). The richest family was Cricetidae (20 spp.), followed by Didelphidae (15 spp.), and Dasypodidae and Felidae (six spp.). Considering national conservation status, one species are considered endangered and 16 vulnerable. Considering global conservation status, 7 species are considered vulnerable, 10 are considered near threatened, and 6 are data deficient. According to the index of frequency of occurrence, Myrmecophaga tridactyla was the most frequent species, occurring at 88.64% of all sites, while 25 species were considered very restricted, occurring in just 2.56% of all sites. In general, the non-volant mammal fauna was composed of mainly very restricted (VR, 25 species) and localized species (L, 25 species), which account for 61.7% of the known species, while 38.3% are restricted (R, 8 species), common (C, 16 species), and widespread (W, 7 species). Seven marsupials and five

  4. Analysis of spatial pattern Change of LU/LC over the upper Tarim River region since 1990 using remote sensing data

    Science.gov (United States)

    Bai, L. Y.; Feng, J. Z.; Ma, Y. X.; Ran, Q. Y.; Wang, K.; Zhao, Y.

    2017-02-01

    The upper reaches of Tarim River (URTR) is an important port of trade between China and central Asia. The development of the URTR is thus significant for the SREB initiative. The LU/LC data in the URTR from 1990 to 2015 were used to quantitatively explore the dynamics of LU/LC changes, and its driving force was discussed from two aspects of nature and human. Results showed that the unused land and grassland were the main land use types in this area, accounting for more than 79%. Compared with the data of 1990, the areas of woodland, water, farmland, and building land of 2015 increased with 3.24%, 6.53%, 10.57%, and 0.40%, respectively, and the areas of unused land and grassland decreased, which accounted for 53.25% and 26.01%, respectively. The increases of the woodland and farmland areas mainly is originated from grassland and unused land. The woodland increased sharply around 2000 due to the abundant water during the period between 1998 and 2000. Subsequently, part of the woodland was shifted into the farmland. The extension of building land wasn’t obvious, but showed a salient feature of population urbanization. It was essential that the LU/LC patterns of the URTR were deeply influenced by human farming and living activities.

  5. Spontaneous combustion of the Upper Paleocene Cerrejon Formation coal and generation of clinker in La Guajira Peninsula (Caribbean Region of Colombia)

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, J.A. [Carbones del Cerrejon Limited., Cl. 100 No. 19-54 piso 12, Bogota D.C. (Colombia); Candela, S.A. [ECOPETROL S.A. Edificio Principal Cr. 7 No. 37-65, Bogota D.C. (Colombia); Rios, C.A. [Escuela de Geologia, Universidad Industrial de Santander, Cr 27 Cl 9, Ciudad Universitaria, Bucaramanga (Colombia); Montes, C. [Smithsonian Tropical Research Institute, Roosvelt Ave., Tupper Building - 401, Balboa, Ancon, Panama (Panama); Uribe, C. [Tubos Moore S.A. Cll 99 No. 57-74, Bogota (Colombia)

    2009-12-01

    Clinker referred here as red and brick-looking burnt rocks found interbedded in the Upper Paleocene Cerrejon Formation is the result of spontaneous and natural combustion of coal seams in the recent geologic past. These rocks have been mapped, measured and characterized in the Cerrejon Coal Mine at La Guajira Peninsula (Colombia). These burnt rocks usually outcrop in irregular patterns as almost tabular bodies up to 100 m thick, thinning and pinching out below ground surface to depths up to 448 m. Mapping revealed that clinker is usually found near deformed zones, either faults or tight folds. Timing of spontaneous combustion seems to predate folding and faulting, but seems to postdate the development of the Cerrejon thrust fault and alluvial fan proceeding from the Perija Range. Clinker covers an area of around 2.9 x 10{sup 6} m{sup 2} with a volume of approximately 1.4 x 10{sup 8} m{sup 3}. The calculation of the amount of heat released through coal burning indicates that complete combustion of 6.4 Mt of 26.4 x 10{sup 6} J/kg coal would yield 17 x 10{sup 13} J. (author)

  6. Are antibiotics over-prescribed in Poland? Management of upper respiratory tract infections in primary health care region of Warszawa, Wola.

    Science.gov (United States)

    Windak, A; Tomasik, T; Jacobs, H M; de Melker, R A

    1996-10-01

    Concern about the increasing numbers of multiple resistant strains resulting from over- and misuse of antibiotics is growing world-wide. A questionnaire based on two cases related to respiratory tract infections for which antibiotic prescription was disputable was sent to primary care physicians in the health care district of Warszawa, Wola, Poland. The prescription percentage for both cases was high, with a large variety in choice of antibiotic therapy made by the doctors. This finding was striking when compared with the more restrictive prescription behaviour of Dutch general practitioners. Moreover, this high prescription percentage was combined with other abundant activities. In the case of the patient with acute tonsillitis, 53% of the primary care physicians would have ordered additional tests, 94% would have advised bed-rest and 9% would have referred. In the sinusitis case, these figures were 88, 74 and 54% respectively. No correlations were found between choice of antibiotics and characteristics of the physicians such as age, gender, experience with working in primary health care or degree of specialization. In conclusion, the results of this small pilot study indicate that Polish first-contact doctors have an inadequate prescription behaviour in cases with upper respiratory tract infections. Our results underline the need for courses in pharmacotherapy within the postgraduate education course in family medicine recently introduced in Poland.

  7. Modified Graded Motor Imagery for Complex Regional Pain Syndrome Type 1 of the Upper Extremity in the Acute Phase: A Patient Series

    Science.gov (United States)

    Lagueux, Emilie; Charest, Joelle; Lefrancois-Caron, Eve; Mauger, Marie-Eve; Mercier, Emilie; Savard, Kim; Tousignant-Laflamme, Yannick

    2012-01-01

    Complex regional pain syndrome (CRPS) is a pathologic condition in which the painful experience is disproportionate in time and intensity in comparison with the inciting event. At present, the pathophysiology of CRPS is not well understood. Several studies have indicated that cortical reorganization plays a role in the persistence of the symptoms.…

  8. Global Coupled Model Studies of The Jovian Upper Atmosphere In Response To Electron Precipitation and Ionospheric Convection Within The Auroral Region.

    Science.gov (United States)

    Millward, G. H.; Miller, S.; Aylward, A. D.

    The Jovian Ionospheric Model (JIM) is a global three-dimensional model of Jupiter's coupled ionosphere and thermosphere, developed at University College London. Re- cently, the model has been used to investigate the atmospheric response to electron precipitation within the high-latitude auroral region. A series of simulations have been performed in which the model atmosphere is subjected to monochromatic precipitat- ing electrons of varying number flux and initial energy and, in addition, to various degrees of ionospheric convection. The auroral ionospheric conductivity which re- sults is shown to be strongly non-linear with respect to the incoming electron energy, with a maximum observed for incident particles of initial energy 60 KeV. Electrons with higher energies penetrate the thermospheric region completely, whilst electrons of lower energy (say 10 keV) produce ionisation at higher levels in the atmosphere which are less less condusive to the creation of ionospheric conductivity. Studies of the thermospheric winds with the auroral region show that zonal winds (around the auroral oval) can attain values of around 70% of the driving zonal ion velocity. Also the results show that these large neutral winds are limited in vertical extent to the region of large ionospheric conductivity, tailing off markedly at altitudes above this. The latest results from this work will be presented, and the implications for Jovian magnetospheric-ionospheric coupling will be discussed.

  9. DISCOVERY OF POLARIZATION REVERBERATION IN NGC 4151

    Energy Technology Data Exchange (ETDEWEB)

    Gaskell, C. Martin; Shoji, Masatoshi [Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588-0111 (United States); Goosmann, Rene W. [Observatoire astronomique de Strasbourg, 11 rue de l' Universite, F-67000 Strasbourg (France); Merkulova, Nelly I.; Shakhovskoy, Nikolay M., E-mail: martin.gaskell@uv.cl, E-mail: mshoji@astro.as.utexas.edu, E-mail: rene.goosmann@astro.unistra.fr [Crimean Astrophysical Observatory, Nauchny, Crimea 98409 (Ukraine)

    2012-04-20

    Observations of the optical polarization of NGC 4151 in 1997-2003 show variations of an order of magnitude in the polarized flux while the polarization position angle remains constant. The amplitude of variability of the polarized flux is comparable to the amplitude of variability of the total U-band flux, except that the polarized flux follows the total flux with a lag of 8 {+-} 3 days. The time lag and the constancy of the position angle strongly favor a scattering origin for the variable polarization rather than a non-thermal synchrotron origin. The orientation of the position angle of the polarized flux (parallel to the radio axis) and the size of the lag imply that the polarization arises from electron scattering in a flattened region within the low-ionization component of the broad-line region. Polarization from dust scattering in the equatorial torus is ruled out as the source of the lag in polarized flux because it would produce a larger lag and, unless the half-opening angle of the torus is >53 Degree-Sign , the polarization would be perpendicular to the radio axis. We note a long-term change in the percentage of polarization at similar total flux levels, and this could be due either to changing non-axisymmetry in the optical continuum emission or a change in the number of scatterers on a timescale of years.

  10. FAINT LUMINESCENT RING OVER SATURN’S POLAR HEXAGON

    Energy Technology Data Exchange (ETDEWEB)

    Adriani, Alberto; D’Aversa, Emiliano; Oliva, Fabrizio; Filacchione, Gianrico [Institute of Space Astrophysics and Planetology of INAF, Via Fosso del Cavaliere 100, I-00133 Rome (Italy); Moriconi, Maria Luisa, E-mail: alberto.adriani@iaps.inaf.it [Institute of Atmospheric Sciences and Climate of CNR, Via Fosso del Cavaliere 100, I-00133 Rome (Italy)

    2015-07-20

    Springtime insolation is presently advancing across Saturn's north polar region. Early solar radiation scattered through the gaseous giant's atmosphere gives a unique opportunity to sound the atmospheric structure at its upper troposphere/lower stratosphere at high latitudes. Here, we report the detection of a tenuous bright structure in Saturn's northern polar cap corresponding to the hexagon equatorward boundary, observed by Cassini Visual and Infrared Mapping Spectrometer on 2013 June. The structure is spectrally characterized by an anomalously enhanced intensity in the 3610–3730 nm wavelength range and near 2500 nm, pertaining to relatively low opacity windows between strong methane absorption bands. Our first results suggest that a strong forward scattering by tropospheric clouds, higher in respect to the surrounding cloud deck, can be responsible for the enhanced intensity of the feature. This can be consistent with the atmospheric dynamics associated with the jet stream embedded in the polar hexagon. Further investigations at higher spectral resolution are needed to better assess the vertical distribution and microphysics of the clouds in this interesting region.

  11. Geomagnetic reversal in brunhes normal polarity epoch.

    Science.gov (United States)

    Smith, J D; Foster, J H

    1969-02-07

    The magnetic stratigraphly of seven cores of deep-sea sediment established the existence of a short interval of reversed polarity in the upper part of the Brunches epoch of normal polarity. The reversed zone in the cores correlates well with paleontological boundaries and is named the Blake event. Its boundaries are estimated to be 108,000 and 114,000 years ago +/- 10 percent.

  12. Polar pesticide contamination of an urban and peri-urban tropical watershed affected by agricultural activities (Yaoundé, Center Region, Cameroon).

    Science.gov (United States)

    Branchet, Perrine; Cadot, Emmanuelle; Fenet, Hélène; Sebag, David; Ngatcha, Benjamin Ngounou; Borrell-Estupina, Valérie; Ngoupayou, Jules Remy Ndam; Kengne, Ives; Braun, Jean-Jacques; Gonzalez, Catherine

    2018-04-18

    Urban agriculture is crucial to local populations, but the risk of it contaminating water has rarely been documented. The aim of this study was to assess pesticide contamination of surface waters from the Méfou watershed (Yaoundé, Cameroon) by 32 selected herbicides, fungicides, and insecticides (mainly polar) according to their local application, using both grab sampling and polar organic compounds integrative samplers (POCIS). Three sampling campaigns were conducted in the March/April and October/November 2015 and June/July 2016 rainy seasons in urban and peri-urban areas. The majority of the targeted compounds were detected. The quantification frequencies of eight pesticides were more than 20% with both POCIS and grab sampling, and that of diuron and atrazine reached 100%. Spatial differences in contamination were evidenced with higher contamination in urban than peri-urban rivers. In particular, diuron was identified as an urban contaminant of concern because its concentrations frequently exceeded the European water quality guideline of 0.200 μg/L in freshwater and may thus represent an ecological risk due to a risk quotient > 1 for algae observed in 94% of grab samples. This study raises concerns about the impacts of urban agriculture on the quality of water resources and to a larger extent on the health of the inhabitants of cities in developing countries. Graphical abstract ᅟ.

  13. Strategic Polarization.

    Science.gov (United States)

    Kalai, Adam; Kalai, Ehud

    2001-08-01

    In joint decision making, similarly minded people may take opposite positions. Consider the example of a marriage in which one spouse gives generously to charity while the other donates nothing. Such "polarization" may misrepresent what is, in actuality, a small discrepancy in preferences. It may be that the donating spouse would like to see 10% of their combined income go to charity each year, while the apparently frugal spouse would like to see 8% donated. A simple game-theoretic analysis suggests that the spouses will end up donating 10% and 0%, respectively. By generalizing this argument to a larger class of games, we provide strategic justification for polarization in many situations such as debates, shared living accommodations, and disciplining children. In some of these examples, an arbitrarily small disagreement in preferences leads to an arbitrarily large loss in utility for all participants. Such small disagreements may also destabilize what, from game-theoretic point of view, is a very stable equilibrium. Copyright 2001 Academic Press.

  14. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Depression Wetlands in the Upper Des Plaines River Basin

    Science.gov (United States)

    2006-05-01

    Wetlands and Coastal Ecology Branch; Dr. David J. Tazik, Chief, Eco- system Evaluation and Engineering Division; and Dr. Edwin A. Theriot, Direc- tor, EL...wetlands (Euliss and Mushet 1996, Azous and Horner 2001, Bhaduri et al. 1997) and nutrient loading into those wetlands. The overall LU score is...Euliss, N. H., and Mushet , D. M. (1996). “Water-level fluctuation in wetlands as a function of landscape condition in the prairie pothole region

  15. Regional development and regional policy

    OpenAIRE

    Šabić, Dejan; Vujadinović, Snežana

    2017-01-01

    Economic polarization is a process that is present at global, national and regional level. Economic activity is extremely spatially concentrated. Cities and developed regions use the agglomeration effect to attract labor and capital, thus achieving more favorable economic conditions than the agrarian region. Scientific research and European experiences over the past decades have contributed to the discrepancy among theorists about the causes and consequences of regional inequalities. Regional...

  16. Mid-Upper Arm Circumference Based Nutrition Programming: Evidence for a New Approach in Regions with High Burden of Acute Malnutrition

    Science.gov (United States)

    Goossens, Sylvie; Bekele, Yodit; Yun, Oliver; Harczi, Géza; Ouannes, Marie; Shepherd, Susan

    2012-01-01

    Background In therapeutic feeding programs (TFP), mid-upper arm circumference (MUAC) shows advantages over weight-for-height Z score (WHZ) and is recommended by the World Health Organization (WHO) as an independent criterion for screening children 6–59 months old. Here we report outcomes and treatment response from a TFP using MUAC ≤118 mm or oedema as sole admission criteria for severe acute malnutrition (SAM). Methods Patient data from September 2007 to March 2009 for children admitted by MUAC ≤118 mm or oedema to a Médecins Sans Frontières (MSF) TFP in Burkina Faso were retrospectively analyzed. Analysis included anthropometric measurements at admission and discharge, program outcomes and treatment response. Results Of 24,792 patient outcomes analyzed, nearly half (48.8%; n = 12,090) were admitted with MUAC 116–118 mm. Most patients (88.7%; n = 21,983) were 6–24 months old. At admission, 52.7% (n = 5,041) of those with MUAC 116–118 mm had a WHZ <−3 SD. At discharge, 89.1% (n = 22,094) recovered (15% weight gain or oedema resolution), 7.9% (n = 1,961) defaulted, 1.5% (n = 384) failed to respond to treatment, and 1.0% (n = 260) died. Average weight gain was 5.4 g/kg/day, and average MUAC gain was 0.42 mm/day. Patients with MUAC ≤114 mm at admission had higher average daily weight and MUAC gains at discharge compared to those admitted with MUAC 116–118 mm, but those in the latter category required longer lengths of stay to achieve recovery (P<0.001). Conclusion This analysis suggests that MUAC ≤118 mm as TFP admission criterion is a useful alternative to WHZ. Regarding treatment response, rates of weight and MUAC gain were acceptable. Applying 15% weight gain as discharge criterion resulted in longer lengths of stay for less malnourished children. Since MUAC gain parallels weight gain, it may be feasible to use MUAC as both an admission and discharge criterion. PMID:23189140

  17. Polarized secondary radioactive beams

    International Nuclear Information System (INIS)

    Zaika, N.I.

    1992-01-01

    Three methods of polarized radioactive nuclei beam production: a) a method nuclear interaction of the non-polarized or polarized charged projectiles with target nuclei; b) a method of polarization of stopped reaction radioactive products in a special polarized ion source with than following acceleration; c) a polarization of radioactive nuclei circulating in a storage ring are considered. Possible life times of the radioactive ions for these methods are determined. General schemes of the polarization method realizations and depolarization problems are discussed

  18. Serological evidence for Saint Louis encephalitis virus in free-ranging New World monkeys and horses within the upper Paraná River basin region, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Walfrido Kühl Svoboda

    2014-06-01

    Full Text Available Introduction Saint Louis encephalitis virus (SLEV primarily occurs in the Americas and produces disease predominantly in humans. This study investigated the serological presence of SLEV in nonhuman primates and horses from southern Brazil. Methods From June 2004 to December 2005, sera from 133 monkeys (Alouatta caraya, n=43; Sapajus nigritus, n=64; Sapajus cay, n=26 trap-captured at the Paraná River basin region and 23 blood samples from farm horses were obtained and used for the serological detection of a panel of 19 arboviruses. All samples were analyzed in a hemagglutination inhibition (HI assay; positive monkey samples were confirmed in a mouse neutralization test (MNT. Additionally, all blood samples were inoculated into C6/36 cell culture for viral isolation. Results Positive seroreactivity was only observed for SLEV. A prevalence of SLEV antibodies in sera was detected in Alouatta caraya (11.6%; 5/43, Sapajus nigritus (12.5%; 8/64, and S. cay (30.8%; 8/26 monkeys with the HI assay. Of the monkeys, 2.3% (1/42 of A. caraya, 6.3% 94/64 of S. nigritus, and 15.4% (4/26 of S. cay were positive for SLEV in the MNT. Additionally, SLEV antibodies were detected by HI in 39.1% (9/23 of the horses evaluated in this study. Arboviruses were not isolated from any blood sample. Conclusions These results confirmed the presence of SLEV in nonhuman primates and horses from southern Brazil. These findings most likely represent the first detection of this virus in nonhuman primates beyond the Amazon region. The detection of SLEV in animals within a geographical region distant from the Amazon basin suggests that there may be widespread and undiagnosed dissemination of this disease in Brazil.

  19. Kharlamova, N. F. Climate Changes over the 20th and 21st Centuries in the Upper Basin of the Ob and Irtysh Rivers (Altai Region)

    Science.gov (United States)

    Fedorovna, K. N., II

    2015-12-01

    The Russian climate is more sensitive to global warming than the climate in many other parts of the world. According to the Second Climate Change National Assessment, since the mid-1970s, the average temperature has been rising with rate of 0.43 ° C / 10 years, which is more than two times higher than the rate of global warming. In the Altai region, the rate of temperature change is higher than the average for Russia with an annual surface air temperature increase equal to 1.8°C the 20th century. The maximum value of this increase the past 50 years (1963-2013) was found in the intermountain basins of Altai (+ 2.6°C) mainly due to the winter and spring warming with changes in the summer season being considerably smaller. This warming is accompanied with negative tendencies in annual precipitation over the entire Altai Krai. The mountain ranges of Altai are called the "water tower" of Northern Eurasia. The northward flow of numerous rivers streaming down from these ranges in the Basin of the Ob and the Irtysh Rivers is formed by melting of Altai glaciers and snowfields. Since the middle of the 19th century the largest glaciers in the Altai have retreated by 1.5-2 km and the thickness of their tails decreased by 50-70 m. The reduction of mountain glaciers poses a threat of depletion of water flow to major agricultural regions downstream affecting human activity and even the drinking water availability. Permafrost in the Altai Mountains is actively degraded (thawing), which represents a danger for infrastructure (first of all for roads and pipelines) and increases risk of catastrophic events (landslides, mudflows). Continued warming could contribute to a significant reduction of water resources, biodiversity and other negative processes in the region.The reported study was partially supported by the Russian Foundation for Baseline Research (project No. 15-45-04450).

  20. Effect of ion entry acceptance conditions on the performance of a quadrupole mass spectrometer operated in upper and lower stability regions

    International Nuclear Information System (INIS)

    Turner, P.; Taylor, S.; Gibson, J.R.

    2005-01-01

    Computer simulation of ion motion in a quadrupole mass spectrometer has been used to examine the effect of initial ion conditions on performance when operated in the first and third zones of the Mathieu stability diagram. Commercial instruments frequently use round electrodes instead of the better-performing hyperbolic electrodes because the cost of manufacturing is lower. However, adverse features are seen when using round electrodes. Here further insight is provided and a possible method of correction is suggested. For the first time, ion origin for the first stability region for a round electrode quadrupole has been reported

  1. Polar crane

    International Nuclear Information System (INIS)

    Makosinski, S.

    1981-01-01

    In many applications polar cranes have to be repeatedly positioned with high accuracy. A guidance system is disclosed which has two pairs of guides. Each guide consists of two rollers carried by a sheave rotatable mounted on the crane bridge, the rollers being locatable one on each side of a guideway, e.g. the circular track on which the bridge runs. The pairs of guides are interconnected by respective rope loops which pass around and are locked to the respective pairs of sheaves in such a manner that movement of one guide results in equal movement of the other guide in a sense to maintain the repeatability of positioning of the centre of the bridge. A hydraulically-linked guide system is also described. (author)

  2. Comparisons of Upper Tropospheric Humidity Retrievals from TOVS and METEOSAT

    Science.gov (United States)

    Escoffier, C.; Bates, J.; Chedin, A.; Rossow, W. B.; Schmetz, J.

    1999-01-01

    Two different methods for retrieving Upper Tropospheric Humidities (UTH) from the TOVS (TIROS Operational Vertical Sounder) instruments aboard NOAA polar orbiting satellites are presented and compared. The first one, from the Environmental Technology Laboratory, computed by J. Bates and D. Jackson (hereafter BJ method), estimates UTH from a simplified radiative transfer analysis of the upper tropospheric infrared water vapor channel at wavelength measured by HIRS (6.3 micrometer). The second one results from a neural network analysis of the TOVS (HIRS and MSU) data developed at, the Laboratoire de Meteorologie Dynamique (hereafter the 3I (Improved Initialization Inversion) method). Although the two methods give very similar retrievals in temperate regions (30-60 N and S), an absolute bias up to 16% appears in the convective zone of the tropics. The two datasets have also been compared with UTH retrievals from infrared radiance measurements in the 6.3 micrometer channel from the geostationary satellite METEOSAT (hereafter MET method). The METEOSAT retrievals are systematically drier than the TOVS-based results by an absolute bias between 5 and 25%. Despite the biases, the spatial and temporal correlations are very good. The purpose of this study is to explain the deviations observed between the three datasets. The sensitivity of UTH to air temperature and humidity profiles is analysed as are the clouds effects. Overall, the comparison of the three retrievals gives an assessment of the current uncertainties in water vapor amounts in the upper troposphere as determined from NOAA and METEOSAT satellites.

  3. Associations between psychological stress and smoking, drinking, obesity, and high blood pressure in an upper middle-income country in the African region.

    Science.gov (United States)

    Chamik, Tanja; Viswanathan, Bharathi; Gedeon, Jude; Bovet, Pascal

    2018-02-01

    The direction and magnitude of the associations between cardiovascular risk factors (CVRFs) and psychological stress continue to be debated, and no data are available from surveys in the African region. In this study, we examine the associations between CVRFs and psychological stress in the Seychelles, a rapidly developing small island state in the African region. A survey was conducted in 1,240 adults aged 25-64 years representative of the Seychelles. Participants were asked to rank psychological stress that they had experienced during the past 12 months in four domains: work, social life, financial situation, and environment around home. CVRFs (high blood pressure, tobacco use, alcohol drinking, and obesity) were assessed using standard procedures. Psychological stress was associated with age, sex, and socioeconomic status. Overall, there were only few consistent associations between psychological stress and CVRFs, adjusting for age, sex, and socioeconomic status. Social stress was associated with smoking, drinking, and obesity, and there were marginal associations between stress at work and drinking, and between financial stress, and smoking and drinking. Psychological stress was not associated with high blood pressure. These findings suggest that psychological stress should be considered in cardiovascular disease prevention and control strategies. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Enriched and depleted characters of the Amnay Ophiolite upper crustal section and the regionally heterogeneous nature of the South China Sea mantle

    Science.gov (United States)

    Perez, Americus d. C.; Faustino-Eslava, Decibel V.; Yumul, Graciano P.; Dimalanta, Carla B.; Tamayo, Rodolfo A.; Yang, Tsanyao Frank; Zhou, Mei-Fu

    2013-03-01

    The volcanic section of the Middle Oligocene Amnay Ophiolite in Mindoro, Philippines has previously been shown to be of normalmid-oceanic ridge basalt (NMORB) composition. Here we report for the first time an enriched mantle component that is additionally recorded in this crustal section. New whole rock major and trace element data are presented for nine mafic volcanic rocks from a section of the ophiolite that has not been previously examined. These moderately evolved tholeiitic basalts were found to have resulted from the bulk mixing of ˜10% ocean island basalt components with depleted mantle. Drawing together various geochemical characteristics reported for different rock suites taken as representatives of the South China Sea crust, including the enriched MORB (EMORB) and NMORB of the East Taiwan Ophiolite, the NMORB from previous studies of the Amnay Ophiolite and the younger ocean floor eruptives of the Scarborough Seamount-Reed Bank region, a veined mantle model is proposed for the South China Sea mantle. The NMORB magmatic products are suggested to have been derived from the more depleted portions of the mantle whereas the ocean island basalt (OIB) and EMORB-type materials from the mixing of depleted and veined/enriched mantle regions.

  5. Geothermal development promotion survey report. No. 29. Upper reach region of Oita river; 1988-1990 chinetsu kaihatsu sokushin chosa hokokusho. No. 29 Oitagawa joryu chiiki

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-03-01

    The results of surveys conducted in the Oita river region, Oita Prefecture, in fiscal 1988-1989 are compiled in this report. Conducted were a geological/alteration zone survey, geochemical survey, electric prospecting (Schlumberger method), electromagnetic surveillance (simplified magnetotelluric method), electromagnetic surveillance (EMAP - Environmental Monitoring and Assessment Program method), heat flow rate survey, test boring, environmental impact survey, and so forth. Conclusions are mentioned below. It is inferred that the geothermal fluid results from groundwater originating in meteoric water, that the meteoric water takes many years to flow from the mountainous region into the ground where it is stored mainly in the Shonai stratum, that the stored water is warmed by heat from rocks in the neighborhood for development into a geothermal fluid, and that the geothermal fluid finally forms a hot spring water reservoir. Hot spring water reservoirs are found widely distributed in the basin of the Oita river. In view of the ground temperature distribution and the hot spring water geochemical temperature determined by structure boring, it is concluded that possibilities are quite low that there exists a high-temperature geothermal fluid usable for power generation. (NEDO)

  6. Spin asymmetries $A_1$ of the proton and the deuteron in the low $x$ and low $Q^2$ region from polarized high energy muon scattering

    CERN Document Server

    AUTHOR|(CDS)2067425; Arvidson, A; Badelek, B; Baum, G; Berglund, P; Betev, L; De Botton, N R; Bradamante, Franco; Bravar, A; Bültmann, S; Burtin, E; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Eichblatt, S; Fasching, D; Feinstein, F; Fernández, C; Frois, Bernard; Gallas, A; Garzón, J A; Gilly, H; Giorgi, M A; von Goeler, E; Görtz, S; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Haft, K; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kiselev, Yu F; Krämer, Dietrich; Kröger, W; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Litmaath, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Meyer, W T; Van Middelkoop, G; Miller, D; Miyachi, Y; Mori, K; Moromisato, J H; Nassalski, J P; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Pereira, H; Perrot-Kunne, F; Peshekhonov, V D; Piegaia, R; Pinsky, L; Platchkov, S K; Pló, M; Pose, D; Postma, H; Pretz, J; Puntaferro, R; Rädel, G; Reicherz, G; Roberts, J; Rodríguez, M; Rondio, Ewa; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Stiegler, U; Stuhrmann, H B; Tessarotto, F; Thers, D; Tlaczala, W; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Whitten, C; Willumeit, R; Windmolders, R; Wislicki, W; Witzmann, A; Zanetti, A M; Zaremba, K; Zhao, J

    1999-01-01

    We present the results of the spin asymmetries $A_1$ of the proton and the deuteron in the kinematic region extending down to $x=6\\cdot 10^{-5}$ and $Q^2=0.01$ GeV$^2$. The data were taken with a dedicated low $x$ trigger, which required hadron detection in addition to the scattered muon, so as to reduce the background at low $x$. The results complement our previous measurements and the two sets are consistent in the overlap region. No sig\\-ni\\-fi\\-cant spin effects are found in the newly explored region.

  7. Strontium and argon isotopic homogenization of pelitic sediments during low-grade regional metamorphism: the Pan-African Upper Damara Sequence of northern Namibia (South West Africa)

    International Nuclear Information System (INIS)

    Clauer, N.

    1979-01-01

    The fine mineral fractions 0 C and pressures up to 2 kbar. These events are dated at about 535 m.y. and 455 m.y. respectively (with lambda( 87 Rb) = 1.42 X 10 -11 yr -1 ). Anomalously high K-Ar ages on samples from specific stratigraphic horizons can be related to open system behaviour and K migration during the formation of stilpnomelane from ferromagnesian illites. This study shows that age dating of sedimentary rocks subjected to low-grade regional metamorphism can only yield meaningful results if the interpretation of isotopic analyses is based on a clear understanding of the mineralogical processes that led to the formation of these parageneses which characterize the rock unit dated. (Auth.)

  8. Causes of childhood blindness in Ghana: results from a blind school survey in Upper West Region, Ghana, and review of the literature.

    Science.gov (United States)

    Huh, Grace J; Simon, Judith; Grace Prakalapakorn, S

    2017-06-13

    Data on childhood blindness in Ghana are limited. The objectives of this study were to determine the major causes of childhood blindness and severe visual impairment (SVI) at Wa Methodist School for the Blind in Northern Ghana, and to compare our results to those published from other studies conducted in Ghana. In this retrospective study, data from an eye screening at Wa Methodist School in November 2014 were coded according to the World Health Organization/Prevention of Blindness standardized reporting methodology. Causes of blindness/SVI were categorized anatomically and etiologically, and were compared to previously published studies. Of 190 students screened, the major anatomical causes of blindness/SVI were corneal scar/phthisis bulbi (CS/PB) (n = 28, 15%) and optic atrophy (n = 23, 12%). The major etiological causes of blindness/SVI were unknown (n = 114, 60%). Eighty-three (44%) students became blind before age one year. Of four published blind school surveys conducted in Ghana, CS/PB was the most common anatomical cause of childhood blindness. Over time, the prevalence of CS/PB within blind schools decreased in the north and increased in the south. Measles-associated visual loss decreased from 52% in 1987 to 10% in 2014 at Wa Methodist School. In a blind school in northern Ghana, CS/PB was the major anatomical cause of childhood blindness/SVI. While CS/PB has been the most common anatomical cause of childhood blindness reported in Ghana, there may be regional changes in its prevalence over time. Being able to identify regional differences may guide future public health strategies to target specific causes.

  9. ON THE COMBINATION OF IMAGING-POLARIMETRY WITH SPECTROPOLARIMETRY OF UPPER SOLAR ATMOSPHERES DURING SOLAR ECLIPSES

    International Nuclear Information System (INIS)

    Qu, Z. Q.; Deng, L. H.; Dun, G. T.; Chang, L.; Zhang, X. Y.; Cheng, X. M.; Qu, Z. N.; Xue, Z. K.; Ma, L.; Allington-Smith, J.; Murray, G.

    2013-01-01

    We present results from imaging polarimetry (IP) of upper solar atmospheres during a total solar eclipse on 2012 November 13 and spectropolarimetry of an annular solar eclipse on 2010 January 15. This combination of techniques provides both the synoptic spatial distribution of polarization above the solar limb and spectral information on the physical mechanism producing the polarization. Using these techniques together we demonstrate that even in the transition region, the linear polarization increases with height and can exceed 20%. IP shows a relatively smooth background distribution in terms of the amplitude and direction modified by solar structures above the limb. A map of a new quantity that reflects direction departure from the background polarization supplies an effective technique to improve the contrast of this fine structure. Spectral polarimetry shows that the relative contribution to the integrated polarization over the observed passband from the spectral lines decreases with height while the contribution from the continuum increases as a general trend. We conclude that both imaging and spectral polarimetry obtained simultaneously over matched spatial and spectral domains will be fruitful for future eclipse observations

  10. Polarization of Coronal Forbidden Lines

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hao; Qu, Zhongquan [Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Landi Degl’Innocenti, Egidio, E-mail: sayahoro@ynao.ac.cn [Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 2, I-50125 Firenze (Italy)

    2017-03-20

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  11. The polarization of NGC 1068

    International Nuclear Information System (INIS)

    Bailey, Jeremy; Axon, D.J.; Hough, J.H.; Heathcote, S.R.

    1988-01-01

    Broad-band polarimetry of NGC 1068 over the wavelength range 0.36-4.8μm is presented, together with high-resolution spectropolarimetry of the Hβ, [O III] and Hα, [N II] regions of the spectrum. We recognize several different polarization components and conclude that they can all be accounted for by processes involving dust. Optical continuum polarization and broad features associated with the Balmer emission lines are due to scattering into the line of sight, of radiation from an obscured Seyfert I nucleus. We argue that the scattering is probably by dust in the narrow line region, but cannot exclude the possibility of electron scattering. (author)

  12. Tracking the Polar Front south of New Zealand using penguin dive data

    Science.gov (United States)

    Sokolov, Serguei; Rintoul, Stephen R.; Wienecke, Barbara

    2006-04-01

    Nearly 36,000 vertical temperature profiles collected by 15 king penguins are used to map oceanographic fronts south of New Zealand. There is good correspondence between Antarctic Circumpolar Current (ACC) front locations derived from temperatures sampled in the upper 150 m along the penguin tracks and front positions inferred using maps of sea surface height (SSH). Mesoscale features detected in the SSH maps from this eddy-rich region are also reproduced in the individual temperature sections based on dive data. The foraging strategy of Macquarie Island king penguins appears to be influenced strongly by oceanographic structure: almost all the penguin dives are confined to the region close to and between the northern and southern branches of the Polar Front. Surface chlorophyll distributions also reflect the influence of the ACC fronts, with the northern branch of the Polar Front marking a boundary between low surface chlorophyll to the north and elevated values to the south.

  13. Report on the inquiry into sale price fluctuations of gasoline and diesel fuel in the regions of Abitibi-Temiscamingue, Saguenay-Lac Saint Jean and the Upper Mauricie, October 1998 to 31 December 1999

    International Nuclear Information System (INIS)

    Lambert, L.; Dumais, M. A.

    2000-01-01

    An inquiry was initiated by the President of the Quebec Energy Board (Regie de l'energie) on October 7, 1999 to review the reasons for the wide fluctuations in the retail sale prices of gasoline and diesel fuel in the regions of Abitibi-Temiscamingue, Saguenay/Lac-Saint-Jean and the Upper Mauricie, although the Board has no jurisdiction over the prices charged for petroleum products or anti-competitive practices. Consequently, the inquiry confined itself to an analysis of the information pertaining to the structure and forces driving the petroleum products market, and an examination of price mechanisms and consumer reactions in these regions. The inquiry reviewed the relevant legislation and regulation, the social, economic and energy situations in the affected regions, and the structure and functioning of the market for gasoline and diesel fuel. The inquiry came to the conclusion that the price fluctuations during the period under review reflected the wholesale prices recorded at Montreal and Quebec, which are determined by national and international market forces over which Quebec has no significant control. Furthermore, the inquiry concluded that although market forces are present and functioning in the regions, there are relatively few outlets affiliated with major oil companies, and a large number of independent retail outlets with relatively small volumes of annual sales. They essentially set their own prices at a level that reflect their cost of operation. Appendices contain the Inquiry's mandate, a list of those who testified before the Inquiry, a map showing the geographic profile of the regions surveyed and a list of figures and tables. 18 tabs., 31 figs

  14. Discovery of Scattering Polarization in the Hydrogen Ly α Line of the Solar Disk Radiation

    International Nuclear Information System (INIS)

    Kano, R.; Narukage, N.; Ishikawa, R.; Bando, T.; Katsukawa, Y.; Kubo, M.; Giono, G.; Hara, H.; Suematsu, Y.; Bueno, J. Trujillo; Winebarger, A.; Kobayashi, K.; Auchère, F.; Ishikawa, S.; Shimizu, T.; Sakao, T.; Tsuneta, S.; Ichimoto, K.; Goto, M.; Belluzzi, L.

    2017-01-01

    There is a thin transition region (TR) in the solar atmosphere where the temperature rises from 10,000 K in the chromosphere to millions of degrees in the corona. Little is known about the mechanisms that dominate this enigmatic region other than the magnetic field plays a key role. The magnetism of the TR can only be detected by polarimetric measurements of a few ultraviolet (UV) spectral lines, the Ly α line of neutral hydrogen at 121.6 nm (the strongest line of the solar UV spectrum) being of particular interest given its sensitivity to the Hanle effect (the magnetic-field-induced modification of the scattering line polarization). We report the discovery of linear polarization produced by scattering processes in the Ly α line, obtained with the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) rocket experiment. The Stokes profiles observed by CLASP in quiet regions of the solar disk show that the Q / I and U / I linear polarization signals are of the order of 0.1% in the line core and up to a few percent in the nearby wings, and that both have conspicuous spatial variations with scales of ∼10 arcsec. These observations help constrain theoretical models of the chromosphere–corona TR and extrapolations of the magnetic field from photospheric magnetograms. In fact, the observed spatial variation from disk to limb of polarization at the line core and wings already challenge the predictions from three-dimensional magnetohydrodynamical models of the upper solar chromosphere.

  15. Discovery of Scattering Polarization in the Hydrogen Ly α Line of the Solar Disk Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kano, R.; Narukage, N.; Ishikawa, R.; Bando, T.; Katsukawa, Y.; Kubo, M.; Giono, G.; Hara, H.; Suematsu, Y. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Bueno, J. Trujillo [Instituto de Astrofísica de Canarias, La Laguna, Tenerife, E-38205 (Spain); Winebarger, A.; Kobayashi, K. [Marshall Space Flight Center, National Aeronautics and Space Administration (NASA), Huntsville, AL 35812 (United States); Auchère, F. [Institut d’Astrophysique Spatiale, Université Paris Sud, Batiment 121, F-91405 Orsay (France); Ishikawa, S.; Shimizu, T.; Sakao, T.; Tsuneta, S. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan); Ichimoto, K. [Hida Observatory, Kyoto University, Takayama, Gifu 506-1314 (Japan); Goto, M. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Belluzzi, L., E-mail: ryouhei.kano@nao.ac.jp [Istituto Ricerche Solari Locarno, CH-6605 Locarno Monti (Switzerland); and others

    2017-04-10

    There is a thin transition region (TR) in the solar atmosphere where the temperature rises from 10,000 K in the chromosphere to millions of degrees in the corona. Little is known about the mechanisms that dominate this enigmatic region other than the magnetic field plays a key role. The magnetism of the TR can only be detected by polarimetric measurements of a few ultraviolet (UV) spectral lines, the Ly α line of neutral hydrogen at 121.6 nm (the strongest line of the solar UV spectrum) being of particular interest given its sensitivity to the Hanle effect (the magnetic-field-induced modification of the scattering line polarization). We report the discovery of linear polarization produced by scattering processes in the Ly α line, obtained with the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) rocket experiment. The Stokes profiles observed by CLASP in quiet regions of the solar disk show that the Q / I and U / I linear polarization signals are of the order of 0.1% in the line core and up to a few percent in the nearby wings, and that both have conspicuous spatial variations with scales of ∼10 arcsec. These observations help constrain theoretical models of the chromosphere–corona TR and extrapolations of the magnetic field from photospheric magnetograms. In fact, the observed spatial variation from disk to limb of polarization at the line core and wings already challenge the predictions from three-dimensional magnetohydrodynamical models of the upper solar chromosphere.

  16. MAPPING THE POLARIZATION OF THE RADIO-LOUD Ly α NEBULA B3 J2330+3927

    Energy Technology Data Exchange (ETDEWEB)

    You, Chang; Zabludoff, Ann; Smith, Paul; Jannuzi, Buell [Steward Observatory, University of Arizona, 933 N Cherry Avenue, Tucson, AZ 85721 (United States); Yang, Yujin [Korea Astronomy and Space Science Institute, 776 Daedeokdae-ro, Yuseong-gu, Daejeon 34055 (Korea, Republic of); Kim, Eunchong; Lee, Myung Gyoon [Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 88226 (Korea, Republic of); Prescott, Moire K. M. [Department of Astronomy, New Mexico State University, 1320 Frenger Mall, Las Cruces, NM 88003 (United States); Matsuda, Yuichi, E-mail: yyang@kasi.re.kr [National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)

    2017-01-10

    Ly α nebulae, or “Ly α blobs,” are extended (up to ∼100 kpc), bright (L{sub Lyα}  ≳ 10{sup 43} erg s{sup −1}) clouds of Ly α emitting gas that tend to lie in overdense regions at z  ∼ 2–5. The origin of the Ly α emission remains unknown, but recent theoretical work suggests that measuring the polarization might discriminate among powering mechanisms. Here we present the first narrowband imaging polarimetry of a radio-loud Ly α nebula, B3 J2330+3927, at z = 3.09, with an embedded active galactic nucleus (AGN). The AGN lies near the blob’s Ly α emission peak, and its radio lobes align roughly with the blob’s major axis. With the SPOL polarimeter on the 6.5 m MMT telescope, we map the total (Ly α + continuum) polarization in a grid of circular apertures of a radius of 0.″6 (4.4 kpc), detecting a significant (>2 σ ) polarization fraction P {sub %} in nine apertures and achieving strong upper limits (as low as 2%) elsewhere. P{sub %} increases from <2% at ∼5 kpc from the blob center to 17% at ∼15–25 kpc. The detections are distributed asymmetrically, roughly along the nebula’s major axis. The polarization angles θ are mostly perpendicular to this axis. Comparing the Ly α flux to that of the continuum and conservatively assuming that the continuum is highly polarized (20%–100%) and aligned with the total polarization, we place lower limits on the polarization of the Ly α emission P{sub %,Lyα} ranging from no significant polarization at ∼5 kpc from the blob center to 3%–17% at 10–25 kpc. Like the total polarization, the Ly α polarization detections occur more often along the blob’s major axis.

  17. MAPPING THE POLARIZATION OF THE RADIO-LOUD Ly α NEBULA B3 J2330+3927

    International Nuclear Information System (INIS)

    You, Chang; Zabludoff, Ann; Smith, Paul; Jannuzi, Buell; Yang, Yujin; Kim, Eunchong; Lee, Myung Gyoon; Prescott, Moire K. M.; Matsuda, Yuichi

    2017-01-01

    Ly α nebulae, or “Ly α blobs,” are extended (up to ∼100 kpc), bright (L Lyα  ≳ 10 43 erg s −1 ) clouds of Ly α emitting gas that tend to lie in overdense regions at z  ∼ 2–5. The origin of the Ly α emission remains unknown, but recent theoretical work suggests that measuring the polarization might discriminate among powering mechanisms. Here we present the first narrowband imaging polarimetry of a radio-loud Ly α nebula, B3 J2330+3927, at z = 3.09, with an embedded active galactic nucleus (AGN). The AGN lies near the blob’s Ly α emission peak, and its radio lobes align roughly with the blob’s major axis. With the SPOL polarimeter on the 6.5 m MMT telescope, we map the total (Ly α + continuum) polarization in a grid of circular apertures of a radius of 0.″6 (4.4 kpc), detecting a significant (>2 σ ) polarization fraction P % in nine apertures and achieving strong upper limits (as low as 2%) elsewhere. P % increases from <2% at ∼5 kpc from the blob center to 17% at ∼15–25 kpc. The detections are distributed asymmetrically, roughly along the nebula’s major axis. The polarization angles θ are mostly perpendicular to this axis. Comparing the Ly α flux to that of the continuum and conservatively assuming that the continuum is highly polarized (20%–100%) and aligned with the total polarization, we place lower limits on the polarization of the Ly α emission P %,Lyα ranging from no significant polarization at ∼5 kpc from the blob center to 3%–17% at 10–25 kpc. Like the total polarization, the Ly α polarization detections occur more often along the blob’s major axis.

  18. Detecting and quantifying the extent of desertification and its impact in the semi-arid Sub-Saharan Africa: A case study of the Upper East Region, Ghana

    Science.gov (United States)

    Owusu, Alex B.

    The semi-arid Sub-Saharan region of Africa is in a state of permanent instability at a variety of spatio-temporal momentum. Efforts at sustaining and managing this fragile but all-important ecosystem and its processes require collecting, storing and analyzing multispatial and temporal data that are accurate and continuously updated in terms of changes (degradation), types and magnitude of change. Remote sensing techniques based on multispectral satellite-acquired data (AVHRR, Landsat TM and ETM+) have demonstrated an immense potential as a means to detect, quantify, monitor and map these changes. However, much of what satellite sensors can detect and capture, especially in the form of vegetation index (NDVI), do not tell the entire story about land degradation. This research used multispectral remote sensing data from three sensors (AVHRR, Landsat TM, and ETM+ and IKONOS) to detect and quantify the spatio-temporal land degradation (desertification) to validate the local observation and perception of desertification. The study also analyzes data on crop production in search of evidence proving or disproving degradation in the semi-arid sahel-sudan savannah transitional vegetation zone of the UER, Ghana. Multispectral satellite-acquired NDVI, from AVHRR, Landsat TM & ETM+, show that vegetation greenness is on the ascendancy, although there are pockets (localized degradation) signs of severe land degradation; field evidence suggests that the increasing NDVI is caused by vegetation succession where locally adapted horsetail grasses have been displaced by environmentally efficient, short-lived, quick maturing and dense grasses due to excessive burning, rapid population growth and inappropriate development policies. Local people's perceptions, supported by crop production data, suggest extensive land degradation. Other evidence includes food insecurity, diseases, rainfall variability and land extensification to marginal lands. Convergence of evidence suggests that

  19. Gemini long-slit observations of luminous obscured quasars: Further evidence for an upper limit on the size of the narrow-line region

    International Nuclear Information System (INIS)

    Hainline, Kevin N.; Hickox, Ryan C.; Greene, Jenny E.; Myers, Adam D.; Zakamska, Nadia L.; Liu, Guilin; Liu, Xin

    2014-01-01

    We examine the spatial extent of the narrow-line regions (NLRs) of a sample of 30 luminous obscured quasars at 0.4 < z < 0.7 observed with spatially resolved Gemini-N GMOS long-slit spectroscopy. Using the [O III] λ5007 emission feature, we estimate the size of the NLR using a cosmology-independent measurement: the radius where the surface brightness falls to 10 –15 erg s –1 cm –2 arcsec –2 . We then explore the effects of atmospheric seeing on NLR size measurements and conclude that direct measurements of the NLR size from observed profiles are too large by 0.1-0.2 dex on average, as compared to measurements made to best-fit Sérsic or Voigt profiles convolved with the seeing. These data, which span a full order of magnitude in IR luminosity (log (L 8 μm /erg s –1 ) = 44.4-45.4), also provide strong evidence that there is a flattening of the relationship between NLR size and active galactic nucleus luminosity at a seeing-corrected size of ∼7 kpc. The objects in this sample have high luminosities which place them in a previously under-explored portion of the size-luminosity relationship. These results support the existence of a maximal size of the NLR around luminous quasars; beyond this size, there is either not enough gas or the gas is over-ionized and does not produce enough [O III] λ5007 emission.

  20. In-flight performance of the polarization modulator in the CLASP rocket experiment

    Science.gov (United States)

    Ishikawa, Shin-nosuke; Shimizu, Toshifumi; Kano, Ryohei; Bando, Takamasa; Ishikawa, Ryoko; Giono, Gabriel; Beabout, Dyana L.; Beabout, Brent L.; Nakayama, Satoshi; Tajima, Takao

    2016-07-01

    We developed a polarization modulation unit (PMU), a motor system to rotate a waveplate continuously. In polarization measurements, the continuous rotating waveplate is an important element as well as a polarization analyzer to record the incident polarization in a time series of camera exposures. The control logic of PMU was originally developed for the next Japanese solar observation satellite SOLAR-C by the SOLAR-C working group. We applied this PMU for the Chromospheric Lyman-alpha SpectroPolarimeter (CLASP). CLASP is a sounding rocket experiment to observe the linear polarization of the Lyman-alpha emission (121.6 nm vacuum ultraviolet) from the upper chromosphere and transition region of the Sun with a high polarization sensitivity of 0.1 % for the first time and investigate their vector magnetic field by the Hanle effect. The driver circuit was developed to optimize the rotation for the CLASP waveplate (12.5 rotations per minute). Rotation non- uniformity of the waveplate causes error in the polarization degree (i.e. scale error) and crosstalk between Stokes components. We confirmed that PMU has superior rotation uniformity in the ground test and the scale error and crosstalk of Stokes Q and U are less than 0.01 %. After PMU was attached to the CLASP instrument, we performed vibration tests and confirmed all PMU functions performance including rotation uniformity did not change. CLASP was successfully launched on September 3, 2015, and PMU functioned well as designed. PMU achieved a good rotation uniformity, and the high precision polarization measurement of CLASP was successfully achieved.

  1. 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

  2. The Upper Atmosphere; Threshold of Space.

    Science.gov (United States)

    Bird, John

    This booklet contains illustrations of the upper atmosphere, describes some recent discoveries, and suggests future research questions. It contains many color photographs. Sections include: (1) "Where Does Space Begin?"; (2) "Importance of the Upper Atmosphere" (including neutral atmosphere, ionized regions, and balloon and investigations); (3)…

  3. Report of the polarization group

    International Nuclear Information System (INIS)

    Ford, W.; Kondo, K.; Martin, F.; Manning, G.; Miller, D.; Prescott, C.

    1975-01-01

    The use of longitudinal polarization in the reaction e + e - → μ + μ - was studied. Modifications of the magnetic insertion which could reduce synchrotron radiation by two or more were considered. In addition, a specific design is suggested which incorporates the optimized magnetic configuration; it is assumed that no particle detection is necessary near the interaction vertex and the synchrotron radiation is ''dumped'' up - and downstream. Also considered were vacuum chambers in which the synchrotron radiation is absorbed locally so that shielded regions are provided for detectors near the interaction vertex. A scheme for rotating the polarization outside the e