WorldWideScience

Sample records for grip global hawk

  1. UAVSAR Global Hawk POLSAR Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Integrate the UAVSAR L-band radar to the Global Hawk UAV Bay 25 Provide long range (~ 9000 nmi) to enable data collection of distant areas of interest without...

  2. LVIS Integration onto Global Hawk Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Integrate LVIS lidar capability onto the Global Hawk (GH) to enable high altitude mapping of land, vegetation, and ice Provide operational capability and data...

  3. Global Hawk Systems Engineering. Case Study

    Science.gov (United States)

    2010-01-01

    as Aurora and Grob. Fourteen teams responded. The bids submitted covered a wide-range of size and performance for a $10 million UFP, causing the...Delos Reyes , 95th Air Base Wing Public Affairs, 1 December 2006 Roll Out of Firs Production Block 10 Global Hawk Systems Engineering Case Study...Delos Reyes , 95th DoD News Briefing, June 28, 1995 Air Base Wing Public Affairs, December 1, 2006 Edwards Test Production Global Hawk for Possible

  4. NASA Global Hawk: A New Tool for Earth Science Research

    Science.gov (United States)

    Hall, Phill

    2009-01-01

    This slide presentation reviews the Global Hawk, a unmanned aerial vehicle (UAV) that NASA plans to use for Earth Sciences research. The Global Hawk is the world's first fully autonomous high-altitude, long-endurance aircraft, and is capable of conducting long duration missions. Plans are being made for the use of the aircraft on missions in the Arctic, Pacific and Western Atlantic Oceans. There are slides showing the Global Hawk Operations Center (GHOC), Flight Control and Air Traffic Control Communications Architecture, and Payload Integration and Accommodations on the Global Hawk. The first science campaign, planned for a study of the Pacific Ocean, is reviewed.

  5. The High Altitude MMIC Sounding Radiometer on the GLOBAL HAWK: From Technology Development to Science Discovery

    Science.gov (United States)

    Brown, Shannon; Denning, Richard; Lambrigtsen, Bjorn; Lim, Boon; Tanabe, Jordan; Tanner, Alan

    2013-01-01

    This paper presents results from the High Altitude MMIC Sounding Radiometer (HAMSR) during three recent field campaigns on the Global Hawk Unmanned Ariel Vehicles (UAV), focusing on the enabling technology that led to unprecedented observations of significant weather phenomenon, such as thermodynamic evolution of the tropical cyclone core during rapid intensification and the high resolution three dimensional mapping of several atmospheric river events. HAMSR is a 25 channel cross-track scanning microwave sounder with channels near the 60 and 118 GHz oxygen lines and the 183 GHz water vapor line. HAMSR was originally designed and built at the Jet Propulsion Laboratory as a technology demonstrator in 1998. Subsequent to this, HAMSR participated in three NASA hurricane field campaigns, CAMEX-4, TCSP and NAMMA. Beginning in 2008, HAMSR was extensively upgraded to deploy on the NASA Global Hawk (GH) platform and serve as an asset to the NASA sub-orbital program. HAMSR has participated on the Global Hawk during the 2010 Genesis and Rapid Intensification (GRIP) campaign, the 2011 Winter Storms and Atmospheric Rivers (WISPAR) campaign and is currently participating in the NASA Ventures Hurricane and Severe Storm Sentinel (HS3) campaign (2011-2015).

  6. Global Hawk Pacific (GloPac) COA and Mission Coordination

    Science.gov (United States)

    Dillon, Mark; Hall, Philip

    2010-01-01

    This slide presentation reviews the science objectives of the Global Hawk unmanned aircraft system (UAS) in the Pacific region, shows examp le flight tracks, the satellite under-flight requirement, the flight planning, and the agencies coordination of the airspace required for the Certificate of Authorization (COA).

  7. HIWRAP Radar Development for High-Altitude Operation on the NASA Global Hawk and ER-2

    Science.gov (United States)

    Li, Lihua; Heymsfield, Gerlad; Careswell, James; Schaubert, Dan; Creticos, Justin

    2011-01-01

    high-altitudes using low peak power transmitters and pulse compression. The hardware will be described along with the methods and concepts for the system design. Finally, we will present recent preliminary results from flights on the NASA Global Hawk in support of the NASA Genesis and Rapid Intensification Processes (GRIP) field campaign, and on the NASA ER-2 as fixed nadir pointing mode for the NASA Global Precipitation Measurement (GPM) ground validation (GV) mission - Midlatitude Continental Convective Cloud Experiment (MC3E)

  8. Hawking radiation from the Schwarzschild black hole with a global monopole via gravitational anomaly

    Institute of Scientific and Technical Information of China (English)

    Peng Jun-Jin; Wu Shuang-Qing

    2008-01-01

    This paper derives the Hawking flux from the Schwarzschild black hole with a global monopole by using Robinson and Wilczek's method.Adopting a dimensional reduction technique, it can describe the effective quantum field in the (3+1)-dimensional global monopole background by an infinite collection of the (1+1)-dimensional maesless fields if neglecting the ingoing modes near the horizon, where the gravitational anomaly can be cancelled by the (1+1)-dimensional black body radiation at the Hawking temperature.

  9. NASA Airborne Science Network Communications Infrastructure for the Global Hawk UAS

    Science.gov (United States)

    Sorenson, C. E.; Sullivan, D.; van Gilst, D. P.

    2010-12-01

    This poster describes the network systems and protocols used for instrument interfaces, remote data access, visualization, and instrument control, for the NASA Global Hawk Unmanned Aircraft System. The Global Hawk's wide range required development of automated instrument status monitoring, low-bandwidth communication techniques for high latitudes, and other means. Live instrument data is incorporated into facility-provided web displays, delivered to experimenter ground stations, and accessed from GIS-enabled servers for external applications. Several of the systems incorporated in the Global Hawk Facility were developed as cross-platform projects for NASA Airborne Science, including the on-board data system, telemetry and data server, and the data display web application. Additionally, simple packet formats were developed with the IWGADTS standards group. As such, this infrastructure represents the first instance of the integrated core set of services which are planned to be provided on all the NASA Airborne Science platform aircraft, implementing a science mission support sensor web.

  10. The Role of the NASA Global Hawk Link Module as an Information Nexus For Atmospheric Mapping Missions

    Science.gov (United States)

    Sullivan, D. V.

    2015-01-01

    The Link Module described in this paper was developed for the NASA Uninhabited Aerial System (UAS) Global Hawk Pacific Mission (GloPAC) Airborne Science Campaign; four flights of 30 hour duration, supporting the Aura Validation Experiment (AVE). It was used again during the Genesis and Rapid Intensification Processes (GRIP) experiment, a NASA Earth Science field experiment to better understand how tropical storms form and develop into major hurricanes. In these missions, the Link Module negotiated all communication over the high bandwidth Ku satellite link, archived all the science data from onboard experiments in a spatially enabled database, routed command and control of the instruments from the Global Hawk Operations Center, and re-transmitted select data sets directly to experimenters control and analysis systems. The availability of aggregated information from collections of sensors, and remote control capabilities, in real-time, is revolutionizing the way Airborne Science is being conducted. The Link Module NG now being flown in support of the NASA Earth Venture missions, the Hurricane and Severe Storm Sentinel (HS3) mission, and Airborne Tropical Tropopause Experiment (A TTREX) mission, has advanced data fusion technologies that are further advancing the Scientific productivity, flexibility and robustness of these systems. On-the-fly traffic shaping has been developed to allow the high definition video, used for critical flight control segments, to dynamically allocate variable bandwidth on demand. Historically, the Link Module evolved from the instrument and communication interface controller used by NASA's Pathfinder and Pathfinder plus solar powered UAS's in the late 1990' s. It later was expanded for use in the AIRDAS four channel scanner flown on the NASA Altus UAS, and then again to a module in the AMS twelve channel multispectral scanner flying on the NASA (Predator-b) Ikhana UAS. The current system is the answer to the challenges imposed by extremely

  11. NASA Global Hawk Project Update and Future Plans: A New Tool for Earth Science Research

    Science.gov (United States)

    Naftel, Chris

    2009-01-01

    Science objectives include: First demonstration of the Global Hawk unmanned aircraft system (UAS) for NASA and NOAA Earth science research and applications; Validation of instruments on-board the Aura satellite; Exploration of trace gases, aerosols, and dynamics of remote upper Troposphere/lower Stratosphere regions; Sample polar vortex fragments and atmospheric rivers; Risk reduction for future missions that will study hurricanes and atmospheric rivers.

  12. High-Altitude MMIC Sounding Radiometer - From the IIP to the Global Hawk

    Science.gov (United States)

    Brown, Shannon; Denning, Richard; Lambrigtsen, Bjorn; Lim, Boon; Tanabe, Jordan; Tanner, Alan; Kangaslahti, Pekka; Gaier, Todd

    2011-01-01

    The HAMSR instrument is a 25 channel cross-track microwave sounder developed by the Jet Propulsion Laboratory under the IIP-98 program. The instrument was recently upgraded under the NASA AITT program in 2008 to deploy on the Global Hawk UAV. The instrument now has state-of-the-art radiometric performance and the capability to process and display both brightness temperature imagery and derived products in real time. The improved performance of the instrument is demonstrated through retrievals of temperature and water vapor.

  13. Oceanic Weather Decision Support for Unmanned Global Hawk Science Missions into Hurricanes with Tailored Satellite Derived Products

    Science.gov (United States)

    Feltz, Wayne; Griffin, Sarah; Velden, Christopher; Zipser, Ed; Cecil, Daniel; Braun, Scott

    2017-04-01

    The purpose of this presentation is to identify in-flight hazards to high-altitude aircraft, namely the Global Hawk. The Global Hawk was used during Septembers 2012-2016 as part of two NASA funded Hurricane Sentinel-3 field campaigns to over-fly hurricanes in the Atlantic Ocean. This talk identifies the cause of severe turbulence experienced over Hurricane Emily (2005) and how a combination of NOAA funded GOES-R algorithm derived cloud top heights/tropical overshooting tops using GOES-13/SEVIRI imager radiances, and lightning information are used to identify areas of potential turbulence for near real-time navigation decision support. Several examples will demonstrate how the Global Hawk pilots remotely received and used real-time satellite derived cloud and lightning detection information to keep the aircraft safely above clouds and avoid regions of potential turbulence.

  14. Global Hawk Dropsonde Observations of the Arctic Atmosphere from March 9-10, 2011

    Science.gov (United States)

    Intrieri, J. M.; Spackman, J. R.; Hughes, M. R.; Neiman, P. J.; Wick, G. A.; Hock, T.; Nghiem, S. V.; Hood, R. E.

    2011-12-01

    In February and March of 2011, the Global Hawk (GH) unmanned aircraft system (UAS) was deployed over the Pacific Ocean and the Arctic in science missions designed to improve our understanding of Pacific weather systems and the polar atmosphere. The missions were not only designed to improve our scientific understanding of atmospheric events in remote environments but to also evaluate the operational use of unmanned aircraft for investigating them. The 116-foot-wingspan Global Hawk, which can soar for 28 hours up to 65,000 feet, was remotely operated from its home at NASA Dryden Flight Research Center on the Edwards Air Force Base in southern California. The field campaign, called Winter Storms and Pacific Atmospheric Rivers (WISPAR), was conducted through a collaborative effort that included NOAA, NASA, and National Center for Atmospheric Research (NCAR). The main objective of the NOAA-led WISPAR campaign was to demonstrate the operational and research applications of a dropsonde system, developed for NOAA by NCAR, for the NASA Global Hawk unmanned aircraft. The dropsondes obtained high-resolution profiles of temperature, pressure, relative humidity, wind speed and direction from the stratosphere to the surface of the ocean, or as in the data presented here, sea ice. The WISPAR science missions targeted three areas of interest; atmospheric rivers (AR), Pacific winter storms, and the Arctic atmosphere. During the 25-hour flight on March 9 and 10, the GH released 35 sondes in the Arctic from just off the North Slope of Alaska to as far as 85° N latitude. En route to and from the Arctic, an additional 35 sondes were dropped in an AR off California and a winter storm off the west coast of Canada. Although the GH Arctic mission is interesting because it transected an unusually cold polar notable for record Arctic ozone loss, in this paper we will examine and present details of the dropsonde data focused primarily on the polar boundary layer to examine atmospheric

  15. Weather Avoidance Guidelines for NASA Global Hawk High-Altitude Unmanned Aircraft Systems (UAS)

    Science.gov (United States)

    Cecil, Daniel J.; Zipser, Edward J.; Velden, Chris S.; Monette, Sarah A.; Heymsfield, Gerald M.; Braun, Scott A.; Newman, Paul A.; Black, Peter G.; Black, Michael L.; Dunion, Jason P.

    2014-01-01

    The current Global Hawk flight rules would probably not have been effective in the single event of greatest concern (the Emily encounter). The cloud top had not reached 50,000 ft until minutes before the encounter. The TOT and lightning data would not have been available until near the overflight time since this was a rapidly growing cell. This case would have required a last-minute diversion when lightning became frequent. Avoiding such a cell probably requires continual monitoring of the forward camera and storm scope, whether or not cloud tops have been exceeding specific limits. However, the current overflight rules as strictly interpreted would have prohibited significant fractions of the successful Global Hawk overpasses of Karl and Matthew that proved not to be hazardous. Many other high altitude aircraft (ER-2 and Global Hawk) flights in NASA tropical cyclone field programs have successfully overflown deep convective clouds without incident.The convective cell that caused serious concern about the safety of the ER-2 in Emily was especially strong for a tropical cyclone environment, probably as strong or stronger than any that was overflown by the ER-2 in 20 previous flights over tropical cyclones. Specifically, what made that cell a safety concern was the magnitude of the vertical velocity of the updraft, at least 20 m/s (4000 ft/minute) at the time the ER-2 overflew it. Such a strong updraft can generate strong gravity waves at and above the tropopause, posing a potential danger to aircraft far above the maximum altitude of the updraft itself or its associated cloud top. Indeed, the ER-2 was probably at least 9000 ft above that cloud top. Cloud-top height, by itself, is not an especially good indicator of the intensity of convection and the likelihood of turbulence. Nor is overflying high cloud tops (i.e. > 50,000 ft) of particular concern unless there is other evidence of very strong convective updrafts beneath those tops in the path of the aircraft

  16. Hawking and Unruh Effects of a 5-Dimensional Minimal Gauged Supergravity Black Hole by a Global Embedding Approach

    Directory of Open Access Journals (Sweden)

    Li-Chun Zhang

    2013-03-01

    Full Text Available Using the new global embedding approach we investigate Unruh/Hawking temperature of the 5-dimensional minimal gauged supergravity black hole with double rotating parameters in a general (1 + 1 space-time. Our results verify that views of Banerjee and Majhi, and extend this approach to a higher dimension situation.

  17. Hawking Radiation from Horizons of Reissner-Nordstr6m de Sitter Black Hole with a Global Monopole via Anomalies

    Institute of Scientific and Technical Information of China (English)

    CHEN Shi-Wu; LIU Xiong-Wei; LIN Kai; ZENG Xiao-Xiong; YANG Shu-Zheng

    2008-01-01

    Hawking radiation from cosmological horizon and event horizon of the Reissner-Nordstrom de Sitter black hole with a global monopole is studied via a new method that was propounded by Robinson and Wilzek and elaborated by Banerjee and Kulkarni. The results show that the gauge current and energy-momentum tensor fluxes, which required keeping gauge covariance and general coordinate invaxiance at the quantum level in the effective field theory, axe exactly equivalent to those of Hawking radiation from the event horizon and the cosmological horizon, respectively.

  18. Global Hawk dropsonde observations of the Arctic atmosphere obtained during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign

    Science.gov (United States)

    Intrieri, J. M.; de Boer, G.; Shupe, M. D.; Spackman, J. R.; Wang, J.; Neiman, P. J.; Wick, G. A.; Hock, T. F.; Hood, R. E.

    2014-11-01

    In February and March of 2011, the Global Hawk unmanned aircraft system (UAS) was deployed over the Pacific Ocean and the Arctic during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign. The WISPAR science missions were designed to (1) mprove our understanding of Pacific weather systems and the polar atmosphere; (2) evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3) demonstrate operational and research applications of a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind information between the stratosphere and surface. The 35 m wingspan Global Hawk, which can soar for ~ 31 h at altitudes up to ~ 20 km, was remotely operated from NASA's Dryden Flight Research Center at Edwards Air Force Base (AFB) in California. During the 25 h polar flight on 9-10 March 2011, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude, marking the first UAS Arctic dropsonde mission of its kind. The polar flight transected an unusually cold polar vortex, notable for an associated record-level Arctic ozone loss, and documented polar boundary layer variations over a sizable ocean-ice lead feature. Comparison of dropsonde observations with atmospheric reanalyses reveal that, for this day, large-scale structures such as the polar vortex and air masses are captured by the reanalyses, while smaller-scale features, including low-level jets and inversion depths, are mischaracterized. The successful Arctic dropsonde deployment demonstrates the capability of the Global Hawk to conduct operations in harsh, remote regions. The limited comparison with other measurements and reanalyses highlights the potential value of Arctic atmospheric dropsonde observations where routine in situ measurements are practically nonexistent.

  19. Global Hawk dropsonde observations of the Arctic atmosphere during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign

    Science.gov (United States)

    Intrieri, J. M.; de Boer, G.; Shupe, M. D.; Spackman, J. R.; Wang, J.; Neiman, P. J.; Wick, G. A.; Hock, T. F.; Hood, R. E.

    2014-04-01

    In February and March of 2011, the Global Hawk unmanned aircraft system (UAS) was deployed over the Pacific Ocean and the Arctic during the WISPAR field campaign. The WISPAR science missions were designed to: (1) improve our understanding of Pacific weather systems and the polar atmosphere; (2) evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3) demonstrate operational and research applications of a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind information between the stratosphere and surface. The 35 m wingspan Global Hawk, which can soar for ~ 31 h at altitudes up to ~ 20 km, was remotely operated from NASA's Dryden Flight Research Center at Edwards AFB in California. During the 25 h polar flight on 9-10 March 2011, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude marking the first UAS Arctic dropsonde mission of its kind. The polar flight transected an unusually cold polar vortex, notable for an associated record-level Arctic ozone loss, and documented polar boundary layer variations over a sizable ocean-ice lead feature. Comparison of dropsonde observations with atmospheric reanalyses reveal that for this day, large-scale structures such as the polar vortex and air masses are captured by the reanalyses, while smaller-scale features, including low-level jets and inversion depths, are mischaracterized. The successful Arctic dropsonde deployment demonstrates the capability of the Global Hawk to conduct operations in harsh, remote regions. The limited comparison with other measurements and reanalyses highlights the value of Arctic atmospheric dropsonde observations where routine in situ measurements are practically non-existent.

  20. Global Hawk dropsonde observations of the Arctic atmosphere during the Winter Storms and Pacific Atmospheric Rivers (WISPAR field campaign

    Directory of Open Access Journals (Sweden)

    J. M. Intrieri

    2014-04-01

    Full Text Available In February and March of 2011, the Global Hawk unmanned aircraft system (UAS was deployed over the Pacific Ocean and the Arctic during the WISPAR field campaign. The WISPAR science missions were designed to: (1 improve our understanding of Pacific weather systems and the polar atmosphere; (2 evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3 demonstrate operational and research applications of a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind information between the stratosphere and surface. The 35 m wingspan Global Hawk, which can soar for ~ 31 h at altitudes up to ~ 20 km, was remotely operated from NASA's Dryden Flight Research Center at Edwards AFB in California. During the 25 h polar flight on 9–10 March 2011, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude marking the first UAS Arctic dropsonde mission of its kind. The polar flight transected an unusually cold polar vortex, notable for an associated record-level Arctic ozone loss, and documented polar boundary layer variations over a sizable ocean-ice lead feature. Comparison of dropsonde observations with atmospheric reanalyses reveal that for this day, large-scale structures such as the polar vortex and air masses are captured by the reanalyses, while smaller-scale features, including low-level jets and inversion depths, are mischaracterized. The successful Arctic dropsonde deployment demonstrates the capability of the Global Hawk to conduct operations in harsh, remote regions. The limited comparison with other measurements and reanalyses highlights the value of Arctic atmospheric dropsonde observations where routine in situ measurements are practically non-existent.

  1. Global Hawk dropsonde observations of the Arctic atmosphere obtained during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign

    OpenAIRE

    J. M. Intrieri; Boer, G.; Shupe, M. D.; J. R. Spackman; J. Wang; P. J. Neiman; Wick, G. A.; T. F. Hock; R. E. Hood

    2014-01-01

    In February and March of 2011, the Global Hawk unmanned aircraft system (UAS) was deployed over the Pacific Ocean and the Arctic during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign. The WISPAR science missions were designed to (1) mprove our understanding of Pacific weather systems and the polar atmosphere; (2) evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3) demonstrate operational and research applic...

  2. The Unique Capabilities of the Global Hawk Aircraft for the Study of Climate Changes

    Science.gov (United States)

    Cairo, F.; Carli, Bruno; Curry, Robert

    2009-01-01

    Due to unprecedented extent and flexibility of the coverage that is now attainable both in space and time, stratospheric unmanned aircraft, such as the Global Hawk (GH), offers new opportunities for the study of climate changes. The capability of performing long flights at altitudes close to the boundary conditions of radiative processes, and of following the diurnal variation of chemical species and clouds, make the GH competitive with LEO and geosynchronous satellites, and even capable of new observations that are not possible from satellites. This paper discusses how the GH can be used to make relevant advancements in most of the issues that are related to climate change studies, such as: Earth Radiation Budget, Water Cycle, Ecosystems and Upper Troposphere-Lower Stratosphere, as well as to the monitoring and control of Greenhouse Gases and Air Quality . Collaboration between NASA and Italian scientific institutions, within the framework of the US.-Italy Cooperation on Climate Change, is providing the opportunity to rapidly deploy new instruments on the GH and to possibly operate the aircraft from an Italian site in the Mediterranean area. From this area, which is considered highly vulnerable to climate change, meridional transects would allow the crossing of Polar and Sub Tropical Jets, as well as a complete crossing of the Inter Tropical Convergence Zone, while latitudinal ones would follow the influx from Asia and North America. Regions otherwise difficult to access, such as Central Africa and the Tibetan Plateau, could be reached and better investigated. An overview of these new opportunities will be given and discussed.

  3. High-Altitude MMIC Sounding Radiometer for the Global Hawk Unmanned Aerial Vehicle

    Science.gov (United States)

    Brown, Shannon T.; Lim, Boon H.; Tanner, Alan B.; Tanabe, Jordan M.; Kangaslahti, Pekka P.; Gaier, Todd C.; Soria, Mary M.; Lambrigtsen, Bjorn H.; Denning, Richard F.; Stachnik, Robert A.

    2012-01-01

    data files are accessed through an Ethernet port. The HAMSR data rate is relatively low at 75 kbps, allowing for real-time access over the Global Hawk high-data-rate downlink. Once on the ground, the raw data are unpacked and processed through two levels of processing. The Level 1 product contains geo-located, time-stamped, calibrated brightness temperatures for the Earth scan. These data are then input to a lD variational retrieval algorithm to produce temperature, water vapor, and cloud liquid water profiles, as well as several derived products such as potential temperature and relative humidity.

  4. New opportunities for the study of Mediterranean storms: the unique capabilities of the Global Hawk aircraft

    Science.gov (United States)

    Cairo, F.; Curry, R. E.; Carli, B.

    2009-09-01

    Airborne measurements have often played a pivotal role in unravelling critical processess and improving our understanding of the genesis and development of atmospheric disturbances. The availability of innovative aerial platforms now opens new perspectives for the scientific research. One of these platforms is the high altitude long endurance unmanned aircraft Global Hawk (GH), which has unique capabilities in terms of altitude, range of operation, diurnal coverage and flexibility. The GH has an endurance of 31 hrs, a service ceiling of 20000 m and can host a payload of 680 kg. Since it can operate at altitudes close to the boundary conditions of radiative processes, can follow the diurnal variation of aerosol and clouds, can rapidly deploy new instruments with space-time coverage comparable to space-borne ones, it is a platform which is at the same time complementary and competitive with satellites. In fact it combines the short time deployment of aircraft instruments with the global coverage of satellite instruments, while its flight altitude allows better spatial resolution than a satellite and its endurance provides a sufficiently broad overview at a scale relevant for sinoptic meteorology studies. NASA has recently acquired two of such unmanned high altitude aircraft to address a variety of Earth Science objectives, and Italy has a decade long experience of stratospheric in-situ and remote sensing science missions using the Russian M-55 "Geophysica" high altitude piloted aircraft. There is a common interest in a bilateral cooperative program in climate change science using the GH. The collaboration between NASA and Italian scientific institutions may offer the opportunity of deploying the GH over the Mediterranean Basin. The Mediterranean area is of particular interest under many respects. As instance, it would be of great interest to measure, when possible, the 3-dimensional structure and evolution of the aerosol content over the Mediterranean, with

  5. GRIPS Plan

    Energy Technology Data Exchange (ETDEWEB)

    1978-07-31

    The GRIPS (Geothermal Resources Impact Projection Study) Commission was established by a Joint Powers Agreement between the California Counties of Lake, Mendocino, Napa, and Sonoma. The objectives of GRIPS are primarily to develop and use a cooperative environmental data collection and use system including natural, social, and economic considerations to facilitate their independent decisions and those of State and Federal agencies related to the environmental effects of geothermal development. This GRIPS Plan was prepared from a wide range of studies, workshops, and staff analyses. The plan is presented in four parts: summary and introduction; environmental data status report; planned programs; and budget. (MHR)

  6. GRIPS bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1978-07-31

    This GRIPS (Geothermal Resources Impact Project Study) contains over 1700 references on a wide variety of subjects dealing directly or indirectly with geothermal development at the Geysers/Calistoga KGRA. (MHR)

  7. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  8. Hurricanes Karl and Tropical Storm Matthew Structure Observed by HIWRAP During GRIP

    Science.gov (United States)

    Heymsfield, G. M.; Guimond, S. R.; Tian, L.

    2012-12-01

    The dual-wavelength (Ku and Ka band) High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) flew for the first time on the Global Hawk during the 2010 Genesis and Rapid Intensification Processes (GRIP). HIWRAP is conical scanning and Doppler, and winds and reflectivity can be mapped within the swath below the Global Hawk. Two interesting cases from the HIWRAP flights were the rapid intensification of Hurricane Karl and the intensification of Tropical Storm Matthew. This presentation will highlight the precipitation and wind structure of these storms during their intensification as derived from the HIWRAP observations. If time permits and if available, highlights from HIWRAP observations from the Hurricane Severe Storm Sentinel (HS3) field campaign in September 2012 will be presented.

  9. Flash Detection Efficiencies of Long Range Lightning Detection Networks During GRIP

    Science.gov (United States)

    Mach, Douglas M.; Bateman, Monte G.; Blakeslee, Richard J.

    2012-01-01

    We flew our Lightning Instrument Package (LIP) on the NASA Global Hawk as a part of the Genesis and Rapid Intensification Processes (GRIP) field program. The GRIP program was a NASA Earth science field experiment during the months of August and September, 2010. During the program, the LIP detected lighting from 48 of the 213 of the storms overflown by the Global Hawk. The time and location of tagged LIP flashes can be used as a "ground truth" dataset for checking the detection efficiency of the various long or extended range ground-based lightning detection systems available during the GRIP program. The systems analyzed included Vaisala Long Range (LR), Vaisala GLD360, the World Wide Lightning Location Network (WWLLN), and the Earth Networks Total Lightning Network (ENTLN). The long term goal of our research is to help understand the advantages and limitations of these systems so that we can utilize them for both proxy data applications and cross sensor validation of the GOES-R Geostationary Lightning Mapper (GLM) sensor when it is launched in the 2015 timeframe.

  10. Hawking radiation of Dirac monopoles from the global monopole black hole with quantum gravity effects

    Science.gov (United States)

    Jusufi, Kimet; Apostolovska, Gordana

    2016-12-01

    In this paper we study the quantum tunneling of Dirac magnetic monopoles from the global monopole black hole under quantum gravity effects. We start from the modified Maxwell's equations and the Generalized Uncertainty Relation (GUP), to recover the GUP corrected temperature for the global monopole black hole by solving the modified Dirac equation via Hamilton-Jacobi method. Furthermore, we also include the quantum corrections beyond the semiclassical approximation, in particular, first we find the logarithmic corrections of GUP corrected entropy and finally we calculate the GUP corrected specific heat capacity. It is argued that the GUP effects may prevent a black hole from complete evaporation and leave remnants.

  11. 球形磁单极荷电黑洞的Hawking辐射%The Hawking Radiation of the Charged Black Hole with a Global Monopole

    Institute of Scientific and Technical Information of China (English)

    刘晶晶; 陈德友

    2008-01-01

    Applying Hamliton-Jacobi method, the tunneling characteristic of the charged black hole with a global monopole is investigated by taking the self-gravitational interaction as well as the energy conservation and charge conservation into account. The radiation spectrum deviates from the purely thermal one and the tunneling probability is related to the change of Bekenstein-Hawking entropy. The result satisfies an underlying unitary theory and gives a correction to the Hawking radiation.%利用Hamliton-Jacobi方法,考虑自引力作用及能量和电荷守恒研究了球形磁单极荷电黑洞的隧穿辐射特性,得到的隧穿辐射谱不再是纯热谱,其隧穿几率与Hawking熵有关,所得到结果满足幺正性原理且对Hawking辐射进行了修正.

  12. Electric Field Measurements During the Genesis and Rapid Intensification Processes (GRIP) Field Program

    Science.gov (United States)

    Bateman, Monte G.; Blakeslee, Richard J.; Mach, Douglas M.

    2010-01-01

    During the Genesis and Rapid Intensification Processes (GRIP) field program, a system of 6 electric field mills was flown on one of NASA's Global Hawk aircraft. We placed several mills on the aircraft to enable us to measure the vector electric field. We created a distributed, ethernet-connected system so that each sensor has its own embedded Linux system, complete with web server. This makes our current generation system fully "sensor web enabled." The Global Hawk has several unique qualities, but relevant to quality storm electric field measurements are high altitude (20 km) and long duration (20-30 hours) flights. There are several aircraft participating in the GRIP program, and coordinated measurements are happening. Lightning and electric field measurements will be used to study the relationships between lightning and other storm characteristics. It has been long understood that lightning can be used as a marker for strong convective activity. Past research and field programs suggest that lightning flash rate may serve as an indicator and precursor for rapid intensification change in tropical cyclones and hurricanes. We have the opportunity to sample hurricanes for many hours at a time and observe intensification (or de-intensification) periods. The electrical properties of hurricanes during such periods are not well known. American

  13. Stephen Hawking

    OpenAIRE

    Duque Escobar, Gonzalo

    2009-01-01

    Obra y vida de este connotado físico, cosmólogo y científico nacido en Oxford y sucesor de la Cátedra Lucasiana en Cambridge, reconocido como el más famoso de los físicos teóricos vivos hoy por su "Breve historia del tiempo", y como una figura legendaria por sus aportes logrados al integrar en una teoría la Relatividad General y la Mecánica Cuántica. Este documento se basa en un resumen del libro “Stephen Hawking para principiantes”, de McEvoy y Zárate, con algunos complementos de la bibliogr...

  14. Greenhouse Observations of the Stratosphere and Troposphere (GHOST): a novel shortwave infrared spectrometer developed for the Global Hawk unmanned aerial vehicle

    Science.gov (United States)

    Humpage, Neil; Boesch, Hartmut; Palmer, Paul; Parr-Burman, Phil; Vick, Andy; Bezawada, Naidu; Black, Martin; Born, Andy; Pearson, David; Strachan, Jonathan; Wells, Martyn

    2014-05-01

    The tropospheric distribution of greenhouse gases (GHGs) is dependent on surface flux variations, atmospheric chemistry and transport processes over a wide range of spatial and temporal scales. Errors in assumed atmospheric transport can adversely affect surface flux estimates inferred from surface, aircraft or satellite observations of greenhouse gas concentrations using inverse models. We present a novel, compact shortwave infrared spectrometer (GHOST) for installation on the NASA Global Hawk unmanned aerial vehicle to provide tropospheric column observations of CO2, CO, CH4, H2O and HDO over the ocean to address the need for large-scale, simultaneous, finely resolved measurements of key GHGs. These species cover a range of lifetimes and source processes, and measurements of their tropospheric columns will reflect the vertically integrated signal of their vertical and horizontal transport within the troposphere. The primary science objectives of GHOST are to: 1) provide observations which can be used to test atmospheric transport models; 2) validate satellite observations of GHG column observations over oceans, thus filling a critical gap in current validation capabilities; and 3) complement in-situ tropopause transition layer tracer observations from other instrumentation on board the Global Hawk to provide a link between upper and lower troposphere concentration measurements. The GHOST spectrometer system comprises a target acquisition module (TAM), a fibre slicer and feed system, and a multiple order spectrograph. The TAM design utilises a gimbal behind an optical dome, which is programmed to direct solar radiation reflected by the ocean surface into a fibre optic bundle. The fibre slicer and feed system then splits the light into the four spectral bands using order sorting filters. The fibres corresponding to each band are arranged with a small sideways offset to correctly centre each spectrum on the detector array. The spectrograph design is unique in that a

  15. Hawking's acting roles

    Science.gov (United States)

    Castell, Stephen

    2012-06-01

    In the wake of Stephen Hawking's appearance on the TV show The Big Bang Theory, last month's "Quanta" page (May p3), included a request: "If you think Hawking should appear in any other TV shows, then let us know".

  16. Domo-Grip: functional evaluation and rehabilitation using grip force.

    Science.gov (United States)

    Hewson, David J; Li, Ke; Frerejean, Alexis; Hogrel, Jean-Yves; Duchene, Jacques

    2010-01-01

    Grip force measurement is routinely used to identify pathologies, evaluate muscular function, and as part of rehabilitation. Grip force has also been shown to be a good indicator of the capacity of elderly to live independently owing to its strong relationship with clinical tests such as the Index of Activities of Daily Living. An autonomous, communicant grip-force measurement device is presented in this paper in order to perform grip-force evaluation at home. The Domo-Grip system consists of the Grip-Ball, the Grip-Box, and Grip-Soft. The Grip-Ball measures the pressure resulting from grip force, the Grip-Box serves as the communication hub, while Grip-Soft is an interactive software suite. The Domo-Grip system can be used as part of a home-based rehabilitation, and also for functional evaluation as part of an assessment of the capacity of elderly to live autonomously.

  17. Hawking, Stephen W (1942-)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    Cosmologist and theoretical astrophysicist, born in Oxford, England, where he studied physics at University College. Moved to Cambridge to take up research in general relativity and cosmology, became Lucasian professor (an appointment earlier held by ISAAC NEWTON, with whom Hawking has been compared). Hawking worked to develop a valid mathematical treatment of the `singularities' in the theor...

  18. Hawking Radiation of Charged and Magnetized Particles from the Global Monopole Black Hole with Quantum Gravity Effects

    CERN Document Server

    Jusufi, Kimet

    2016-01-01

    In this paper we study the quantum tunneling of charged and magnetized particles (magnetic monopoles) from the global monopole black hole by incorporating the quantum gravity effects. Starting from the modified Maxwell's equations and Generalized Uncertainty Relation (GUP), we recover the GUP corrected temperate for the global monopole black hole by solving the modified Dirac equation via Hamilton-Jacobi method. Furthermore, we also include the quantum corrections beyond the semiclassical approximation, in particular, first we find the logarithmic corrections of GUP corrected entropy and finally we calculate the GUP corrected specific heat capacity.

  19. Mapping Hawking into Unruh thermal properties

    OpenAIRE

    S. Deser; Levin, Orit

    1999-01-01

    By globally embedding curved spaces into higher dimensional flat ones, we show that Hawking thermal properties map into their Unruh equivalents: The relevant curved space detectors become Rindler ones, whose temperature and entropy reproduce the originals. Specific illustrations include Schwarzschild, Schwarzschild–(anti-)de Sitter, Reissner-Nordström, and Bañados-Teitelboim-Zanelli spaces.

  20. Hand grip strength

    DEFF Research Database (Denmark)

    Frederiksen, Henrik; Gaist, David; Petersen, Hans Christian

    2002-01-01

    in life is a major problem in terms of prevalence, morbidity, functional limitations, and quality of life. It is therefore of interest to find a phenotype reflecting physical functioning which has a relatively high heritability and which can be measured in large samples. Hand grip strength is known......-55%). A powerful design to detect genes associated with a phenotype is obtained using the extreme discordant and concordant sib pairs, of whom 28 and 77 dizygotic twin pairs, respectively, were found in this study. Hence grip strength is a suitable phenotype for identifying genetic variants of importance to mid...

  1. Perfect simulation of Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    This article concerns a perfect simulation algorithm for unmarked and marked Hawkes processes. The usual stratihtforward simulation algorithm suffers from edge effects, whereas our perfect simulation algorithm does not. By viewing Hawkes processes as Poisson cluster processes and using...

  2. Steven Hawking with Robert Aymar

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    Steven Hawking is seen meeting with CERN's Director-General, Robert Aymar. Hawking visited CERN between 24 September and 1 October 2006. During his stay he gave two lectures and toured the LHC, which may provide insights into Hawking's most famous area of study, black holes.

  3. Hawking radiation is corpuscular

    CERN Document Server

    Mück, Wolfgang

    2016-01-01

    The total number of Hawking quanta emitted during the evaporation of a Schwarzschild black hole is proportional to the square of the initial mass and proportional to the Bekenstein entropy. This simple, but seemingly unnoticed, fact is interpreted in terms of the recent discovery of black hole soft hair.

  4. Enter the Gripping Beast

    DEFF Research Database (Denmark)

    Sindbæk, Søren Michael

    2012-01-01

    of communities and their life world. Transcending technology, cultural dispositions and social relations, the study of innovations invites an actor-networks approach, which considers the heterogeneous nature of human-material relations. The archaeological record is potentially a rich source of evidence...... on innovations. Mostly, however, the time-resolution of archaeological data is too coarse-grained to allow us to grasp this potential to the full. In the period c. AD 790-850 a distinctly new artistic motif, the Gripping Beast, emerged in Scandinavia. A series of narrowly dated contexts provide anchor points...

  5. Fading Hawking Radiation

    CERN Document Server

    Sakalli, I; Pasaoglu, H

    2012-01-01

    In this study, we explore a particular type Hawking radiation which ends with zero temperature and entropy. The appropriate black holes for this purpose are the linear dilaton black holes. In addition to the black hole choice, a recent formalism in which the Parikh-Wilczek's tunneling formalism amalgamated with quantum corrections to all orders in \\hbar is considered. The adjustment of the coefficients of the quantum corrections plays a crucial role on this particular Hawking radiation. The obtained tunneling rate indicates that the radiation is not pure thermal anymore, and hence correlations of outgoing quanta are capable of carrying away information encoded within them. Finally, we show in detail that when the linear dilaton black hole completely evaporates through such a particular radiation, entropy of the radiation becomes identical with the entropy of the black hole, which corresponds to "no information loss".

  6. Canadian institute honours Hawking

    Science.gov (United States)

    Durrani, Matin

    2009-11-01

    The Perimeter Institute for Theoretical Physics in Waterloo, Canada, has announced that a major new extension to its campus will be known as the Stephen Hawking Centre. The extension, which is currently being built, is due to open in 2011 and will double the size of the institute. It will also provide a home for the institute's Masters students, the first of whom joined the Perimeter Institute this autumn as part of its Perimeter Scholars international programme.

  7. Hawking Radiation in Dispersive Media

    CERN Document Server

    Robertson, Scott James

    2011-01-01

    Hawking radiation, despite its presence in theoretical physics for over thirty years, remains elusive and undetected. It also suffers, in its original context of gravitational black holes, from conceptual difficulties. Of particular note is the trans-Planckian problem, which is concerned with the apparent origin of the radiation in absurdly high frequencies. In order to gain better theoretical understanding and, it is hoped, experimental verification of Hawking radiation, much study is being devoted to systems which model the spacetime geometry of black holes, and which, by analogy, are also thought to emit Hawking radiation. These analogue systems typically exhibit dispersion, which regularizes the wave behaviour at the horizon but does not lend itself well to analytic treatment, thus rendering Hawking's prediction less secure. A general analytic method for dealing with Hawking radiation in dispersive systems has proved difficult to find. This thesis presents new numerical and analytic results for Hawking em...

  8. Approximate simulation of Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    2006-01-01

    Hawkes processes are important in point process theory and its applications, and simulation of such processes are often needed for various statistical purposes. This article concerns a simulation algorithm for unmarked and marked Hawkes processes, exploiting that the process can be constructed...

  9. Perfect simulation of Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    2005-01-01

    Our objective is to construct a perfect simulation algorithm for unmarked and marked Hawkes processes. The usual straightforward simulation algorithm suffers from edge effects, whereas our perfect simulation algorithm does not. By viewing Hawkes processes as Poisson cluster processes and using...

  10. Chinese President Meets Stephen Hawking

    Institute of Scientific and Technical Information of China (English)

    Fu Shuqin

    2002-01-01

    @@ Chinese President Jiang Zemin met on August 19 with Stephen Hawking and other world-renown scientists, including Shing-tung Yau, Edward Witten, D.Gross, A. Strominger, et al., who were attending an international conference on string theory and Prof.Hawking had just given a public speech titled "Brane New World" in Beijing.

  11. Finding Relief from Allergy's Grip

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Finding Relief from Allergy's Grip Past Issues / Summer 2006 Table ... action for patients who have had inadequate symptom relief with antihistamines and topical nasal steroids. Through injection ...

  12. Hawking from Catalan

    CERN Document Server

    Fitzpatrick, A Liam; Walters, Matthew T; Wang, Junpu

    2015-01-01

    The Virasoro algebra determines all `graviton' matrix elements in AdS$_3$/CFT$_2$. We study the explicit exchange of any number of Virasoro gravitons between heavy and light CFT$_2$ operators at large central charge. These graviton exchanges can be written in terms of new on-shell tree diagrams, organized in a perturbative expansion in $h_H/c$, the heavy operator dimension divided by the central charge. The Virasoro vacuum conformal block, which is the sum of all the tree diagrams, obeys a differential recursion relation generalizing that of the Catalan numbers. We use this recursion relation to sum the on-shell diagrams to all orders, computing the Virasoro vacuum block. Extrapolating to large $h_H/c$ determines the Hawking temperature of a BTZ black hole in dual AdS$_3$ theories.

  13. Hawk and Handsaw

    Science.gov (United States)

    Usher, Peter D.

    2008-05-01

    In Shakespeare's Hamlet, Prince Hamlet states, "I am but mad north-north-west. When the wind is southerly, I know a hawk from a handsaw." This celebrated yet perennially baffling passage is readily understood in the context of the cosmic allegorical interpretation of the play (BAAS 28, 1305, 1996; Hamlet's Universe, 2006). The first direction points from Tycho Brahe's observatory on Hven to the fictional home of the geocentric Pyolemaic worldview at Elsinore, and the second from Hven to the home of Copernican heliocentricism at Wittenberg. The directions correspond to the two influences on Tycho's geo-heliocentric World model. Anyone at Elsinore who advocates the new organon of the New Philosophy is "mad," whereas sanity prevails at Wittenberg. "Hawk" refers to a bird of prey, the leonard, and to Leonard Digges, inventor of the world's first two-element telescope. "Handsaw" refers to the artistic tool necessary to sever the hands depicted in de Gheyn's two quasi-mirror-imaged portraits of Tycho at age 40, which show hands affixed to the wrong arms. Elsewhere in Hamlet, Shakespeare substantiates the New Astronomy through descriptions of planets and stars that could only have been determined telescopically. Therefore, the passage in question contrasts two modes of observing in the early modern era, viz. visual and telescopic. Shakespeare completed writing Hamlet in about 1601 and the Second Quarto appeared in 1604, so the first substantial account of astronomical telescopy is now over 400 years old. In addition, 432 years ago Thomas Digges published the first account of the New Astronomy in a popular almanac. These two means of presentation may seem odd by present standards, but contemporary culture was intolerant of 'natural magic,' and furthermore, it was prudent to minmize the risk of domestic persecution and threats from Continental armies and the European and Spanish Inquisitions.

  14. Development of the Hawk/Nike Hawk sounding rocket vehicles

    Science.gov (United States)

    Flowers, B. J.

    1976-01-01

    A new sounding rocket family, the Hawk and Nike-Hawk Vehicles, have been developed, flight tested and added to the NASA Sounding Rocket Vehicle Stable. The Hawk is a single-stage vehicle that will carry 35.6 cm diameter payloads weighing 45.5 kg to 91 kg to altitudes of 78 km to 56 km, respectively. The two-stage Nike-Hawk will carry payloads weighing 68 kg to 136 kg to altitudes of 118 km to 113 km, respectively. Both vehicles utilize the XM22E8 Hawk rocket motor which is available in large numbers as a surplus item from the U.S. Army. The Hawk fin and tail can hardware were designed in-house. The Nike tail can and fin hardware are surplus Nike-Ajax booster hardware. Development objectives were to provide a vehicle family with a larger diameter, larger volume payload capability than the Nike-Apache and Nike-Tomahawk vehicles at comparable cost. Both vehicles performed nominally in flight tests.

  15. Development of the Hawk/Nike Hawk sounding rocket vehicles

    Science.gov (United States)

    Flowers, B. J.

    1976-01-01

    A new sounding rocket family, the Hawk and Nike-Hawk Vehicles, have been developed, flight tested and added to the NASA Sounding Rocket Vehicle Stable. The Hawk is a single-stage vehicle that will carry 35.6 cm diameter payloads weighing 45.5 kg to 91 kg to altitudes of 78 km to 56 km, respectively. The two-stage Nike-Hawk will carry payloads weighing 68 kg to 136 kg to altitudes of 118 km to 113 km, respectively. Both vehicles utilize the XM22E8 Hawk rocket motor which is available in large numbers as a surplus item from the U.S. Army. The Hawk fin and tail can hardware were designed in-house. The Nike tail can and fin hardware are surplus Nike-Ajax booster hardware. Development objectives were to provide a vehicle family with a larger diameter, larger volume payload capability than the Nike-Apache and Nike-Tomahawk vehicles at comparable cost. Both vehicles performed nominally in flight tests.

  16. Swainson's Hawk - Monitoring [ds5

    Data.gov (United States)

    California Department of Resources — These data do not represent a complete census of Swainson's hawks in the Department of Fish and Game's Central Valley Central Sierra Region. Different sample blocks...

  17. Uninformed Hawking Radiation

    CERN Document Server

    Sakalli, I

    2014-01-01

    We show in detail that the Parikh-Wilczek tunneling method (PWTM), which was designed for resolving the information loss problem in Hawking radiation (HR)fails whenever the radiation occurs from an isothermal process. The PWTM aims to produce a non-thermal HR which adumbrates the resolution of the problem of unitarity in quantum mechanics (QM), and consequently the entropy (or information) conservation problem. The effectiveness of the method has been satisfactorily tested on numerous black holes (BHs). However, it has been shown that the isothermal HR, which results from the emission of the uncharged particles of the linear dilaton BH (LDBH) described in the Einstein-Maxwell-Dilaton (EMD) theory, the PWTM has vulnerability in having non-thermal radiation. In particular, we consider Painlev\\'{e}-Gullstrand coordinates (PGCs) and isotropic coordinates (ICs) in order to prove the aformentioned failure in the PWTM. While carrying out calculations in the ICs, we also highlight the effect of the refractive index o...

  18. Uninformed Hawking radiation

    Science.gov (United States)

    Sakalli, I.; Ovgun, A.

    2015-04-01

    We show in detail that the Parikh-Wilczek tunneling method (PWTM), which was designed for resolving the information loss problem in Hawking radiation (HR) fails whenever the radiation occurs from an isothermal process. The PWTM aims to produce a non-thermal HR which adumbrates the resolution of the problem of unitarity in quantum mechanics (QM), and consequently the entropy (or information) conservation problem. The effectiveness of the method has been satisfactorily tested on numerous black holes (BHs). However, it has been shown that the isothermal HR, which results from the emission of the uncharged particles of the linear dilaton BH (LDBH) described in the Einstein-Maxwell-Dilaton (EMD) theory, the PWTM has vulnerability in having non-thermal radiation. In particular, we consider Painlevé-Gullstrand coordinates (PGCs) and isotropic coordinates (ICs) in order to prove the aforementioned failure in the PWTM. While carrying out calculations in the ICs, we also highlight the effect of the refractive index on the null geodesics.

  19. Vacuum polarization and Hawking radiation

    Science.gov (United States)

    Rahmati, Shohreh

    Quantum gravity is one of the interesting fields in contemporary physics which is still in progress. The purpose of quantum gravity is to present a quantum description for spacetime at 10-33cm or find the 'quanta' of gravitational interaction.. At present, the most viable theory to describe gravitational interaction is general relativity which is a classical theory. Semi-classical quantum gravity or quantum field theory in curved spacetime is an approximation to a full quantum theory of gravity. This approximation considers gravity as a classical field and matter fields are quantized. One interesting phenomena in semi-classical quantum gravity is Hawking radiation. Hawking radiation was derived by Stephen Hawking as a thermal emission of particles from the black hole horizon. In this thesis we obtain the spectrum of Hawking radiation using a new method. Vacuum is defined as the possible lowest energy state which is filled with pairs of virtual particle-antiparticle. Vacuum polarization is a consequence of pair creation in the presence of an external field such as an electromagnetic or gravitational field. Vacuum polarization in the vicinity of a black hole horizon can be interpreted as the cause of the emission from black holes known as Hawking radiation. In this thesis we try to obtain the Hawking spectrum using this approach. We re-examine vacuum polarization of a scalar field in a quasi-local volume that includes the horizon. We study the interaction of a scalar field with the background gravitational field of the black hole in the desired quasi-local region. The quasi-local volume is a hollow cylinder enclosed by two membranes, one inside the horizon and one outside the horizon. The net rate of particle emission can be obtained as the difference of the vacuum polarization from the outer boundary and inner boundary of the cylinder. Thus we found a new method to derive Hawking emission which is unitary and well defined in quantum field theory.

  20. Hawk migration over White Marsh, Maryland

    Science.gov (United States)

    Hackman, C.D.; Henny, C.J.

    1971-01-01

    The average number of hawks observed per hour in autumn migration between 1951-1954 and 1958-1961 at White Marsh, Maryland, was compared. The counts indicated that the status of the ten species observed may be divided into three categories: (1) relatively stable species (red-tailed hawk), (2) declining species (sparrow hawk, red-shouldered hawk, osprey, marsh hawk, and broad-winged hawk), and (3) rapidly declining species (peregrine falcon, Cooper?s hawk, bald eagle, and sharp-shinned hawk). The findings from this study are in agreement with the available literature and the status of the populations appears to be related to the food habits of the species.

  1. Gripping System For Mechanical Testing Of Composites

    Science.gov (United States)

    Mackay, Rebecca A.; Nathal, Michael V.

    1994-01-01

    Specimens held without slippage, even at high temperatures. Improved gripping system designed to securely hold ends of specimen of composite material during creep or tensile test. Each grip includes pair of wedges having sharply corrugated gripping surfaces. Wedges held between two plates containing cavities sloped to accommodate wedges. Two such grips (one for each end) holds specimen in furnace connected to tensile test machine for creep measurements.

  2. Stephen Hawking: An Unfettered Mind

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, Kitty

    2012-02-23

    Kitty Ferguson, biographer of physicist Stephen Hawking, will give an informal, nontechnical talk about the experience of writing her two books about the celebrated cosmologist and also of helping Hawking edit his own “The Universe in a Nutshell”. Hawking thinks and works somewhat differently from others because he must work almost entirely in his head, and he has a practice of pulling the rug out from under his own discoveries and assertions. As he has approached his recent 70th birthday, he has devoted an increasing amount of his time in efforts to share his science and particularly the adventure of it with people without a science background and young people who may be scientists of the future. Ferguson will discuss Hawking’s place in the science community (he is not and has never claimed to be on par with Einstein), the unique contributions he is able to make, and what his legacy might be.

  3. Hawking radiation without transplanckian frequencies

    CERN Document Server

    Brout, R; Parentani, R; Spindel, P

    1995-01-01

    In a recent work, Unruh showed that Hawking radiation is unaffected by a truncation of free field theory at the Planck scale. His analysis was performed numerically and based on a hydrodynamical model. In this work, by analytical methods, the mathematical and physical origin of Unruh's result is revealed. An alternative truncation scheme which may be more appropriate for black hole physics is proposed and analyzed. In both schemes the thermal Hawking radiation remains unaffected even though transplanckian energies no longer appear. The universality of this result is explained by working in momentum space. In that representation, in the presence of a horizon, the d'Alembertian equation becomes a singular first order equation. In addition, the boundary conditions corresponding to vacuum before the black hole formed are that the in--modes contain positive momenta only. Both properties remain valid when the spectrum is truncated and they suffice to obtain Hawking radiation.

  4. Second order analysis for spatial Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Torrisi, Giovanni Luca

    We derive summary statistics for stationary Hawkes processes which can be considered as spatial versions of classical Hawkes processes. Particularly, we derive the intensity, the pair correlation function and the Bartlett spectrum. Our results for Gaussian fertility rates and the extension...... to marked Hawkes processes are discussed....

  5. HAWK-I Takes Off

    Science.gov (United States)

    2007-08-01

    New Wide Field Near-Infrared Imager for ESO's Very Large Telescope Europe's flagship ground-based astronomical facility, the ESO VLT, has been equipped with a new 'eye' to study the Universe. Working in the near-infrared, the new instrument - dubbed HAWK-I - covers about 1/10th the area of the Full Moon in a single exposure. It is uniquely suited to the discovery and study of faint objects, such as distant galaxies or small stars and planets. ESO PR Photo 36a/07 ESO PR Photo 36a/07 HAWK-I on the VLT After three years of hard work, HAWK-I (High Acuity, Wide field K-band Imaging) saw First Light on Yepun, Unit Telescope number 4 of ESO's VLT, on the night of 31 July to 1 August 2007. The first images obtained impressively demonstrate its potential. "HAWK-I is a credit to the instrument team at ESO who designed, built and commissioned it," said Catherine Cesarsky, ESO's Director General. "No doubt, HAWK-I will allow rapid progress in very diverse areas of modern astronomy by filling a niche of wide-field, well-sampled near-infrared imagers on 8-m class telescopes." "It's wonderful; the instrument's performance has been terrific," declared Jeff Pirard, the HAWK-I Project Manager. "We could not have hoped for a better start, and look forward to scientifically exciting and beautiful images in the years to come." During this first commissioning period all instrument functions were checked, confirming that the instrument performance is at the level expected. Different astronomical objects were observed to test different characteristics of the instrument. For example, during one period of good atmospheric stability, images were taken towards the central bulge of our Galaxy. Many thousands of stars were visible over the field and allowed the astronomers to obtain stellar images only 3.4 pixels (0.34 arcsecond) wide, uniformly over the whole field of view, confirming the excellent optical quality of HAWK-I. ESO PR Photo 36b/07 ESO PR Photo 36c/07 Nebula in Serpens (HAWK

  6. Evaluation of pliers' grip spans in the maximum gripping task and sub-maximum cutting task.

    Science.gov (United States)

    Kim, Dae-Min; Kong, Yong-Ku

    2016-12-01

    A total of 25 males participated to investigate the effects of the grip spans of pliers on the total grip force, individual finger forces and muscle activities in the maximum gripping task and wire-cutting tasks. In the maximum gripping task, results showed that the 50-mm grip span had significantly higher total grip strength than the other grip spans. In the cutting task, the 50-mm grip span also showed significantly higher grip strength than the 65-mm and 80-mm grip spans, whereas the muscle activities showed a higher value at 80-mm grip span. The ratios of cutting force to maximum grip strength were also investigated. Ratios of 30.3%, 31.3% and 41.3% were obtained by grip spans of 50-mm, 65-mm, and 80-mm, respectively. Thus, the 50-mm grip span for pliers might be recommended to provide maximum exertion in gripping tasks, as well as lower maximum-cutting force ratios in the cutting tasks.

  7. Hydraulically Driven Grips For Hot Tensile Specimens

    Science.gov (United States)

    Bird, R. Keith; Johnson, George W.

    1994-01-01

    Pair of grips for tensile and compressive test specimens operate at temperatures up to 1,500 degrees F. Grips include wedges holding specimen inside furnace, where heated to uniform temperature. Hydraulic pistons drive wedges, causing them to exert clamping force. Hydraulic pistons and hydraulic fluid remain outside furnace, at room temperature. Cooling water flows through parts of grips to reduce heat transferred to external components. Advantages over older devices for gripping specimens in high-temperature tests; no need to drill holes in specimens, maintains constant gripping force on specimens, and heated to same temperature as that of specimen without risk of heating hydraulic fluid and acuator components.

  8. Bayesian inference for Hawkes processes

    DEFF Research Database (Denmark)

    Rasmussen, Jakob Gulddahl

    The Hawkes process is a practically and theoretically important class of point processes, but parameter-estimation for such a process can pose various problems. In this paper we explore and compare two approaches to Bayesian inference. The first approach is based on the so-called conditional...

  9. Bayesian inference for Hawkes processes

    DEFF Research Database (Denmark)

    Rasmussen, Jakob Gulddahl

    2013-01-01

    The Hawkes process is a practically and theoretically important class of point processes, but parameter-estimation for such a process can pose various problems. In this paper we explore and compare two approaches to Bayesian inference. The first approach is based on the so-called conditional...

  10. Bayesian inference for Hawkes processes

    DEFF Research Database (Denmark)

    Rasmussen, Jakob Gulddahl

    The Hawkes process is a practically and theoretically important class of point processes, but parameter-estimation for such a process can pose various problems. In this paper we explore and compare two approaches to Bayesian inference. The first approach is based on the so-called conditional...

  11. Stephen Hawking's Universe. Teacher's Guide.

    Science.gov (United States)

    Thompson, Malcolm H.; Rameau, Jonathan D.

    This program guide is meant to help teachers assist their students in viewing the six-part public television series, "Stephen Hawking's Universe." The guide features program summaries that give background information and brief synopses of the programs; previewing activities that familiarize students with the subject; vocabulary that…

  12. Approximate simulation of Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    This article concerns a simulation algorithm for unmarked and marked Hawkes processes. The algorithm suffers from edge effects but is much faster than the perfect simulation algorithm introduced in our previous work. We derive various useful measures for the error committed when using the algorithm...

  13. Hawking Colloquium Packed CERN Auditoriums

    CERN Multimedia

    2006-01-01

    Stephen Hawking's week long visit to CERN included an 'exceptional CERN colloquium' which filled six auditoriums. Stephen Hawking during his visit to the ATLAS experiment. Stephen Hawking, Lucasian Professor of Cambridge University, visited the Theory Unit of the Physics Department from 24 September to 1 October 2006. As part of his visit, he gave two lectures in the main auditorium - a theoretical seminar on 'The Semi-Classical Birth of The Universe', attended by about 120 specialists; and a colloquium titled 'The Origin of The Universe'. As a key public figure in theoretical physics, his presence was eagerly awaited on both occasions. Those who wanted to attend the colloquium had to arrive early and be equipped with plenty of patience. An hour before it was due to begin, the 400 capacity of the main auditorium was already full. The lecture, simultaneously broadcast to five other fully packed CERN auditoriums, was attended by an estimated total of 850. Stephen Hawking attracted a large CERN crowd, filling ...

  14. Motor cortical function and the precision grip.

    Science.gov (United States)

    Geevasinga, Nimeshan; Menon, Parvathi; Kiernan, Matthew C; Vucic, Steve

    2014-12-01

    While task-dependent changes in motor cortical outputs have been previously reported, the issue of whether such changes are specific for complex hand tasks remains unresolved. The aim of the present study was to determine whether cortical inhibitory tone and cortical output were greater during precision grip and power grip. Motor cortex excitability was undertaken by using the transcranial magnetic stimulation threshold tracking technique in 15 healthy subjects. The motor-evoked potential (MEP) responses were recorded over the abductor pollicis brevis (APB), with the hand in the following positions: (1) rest, (2) precision grip and (3) power grip. The MEP amplitude (MEP amplitude REST 23.6 ± 3.3%; MEP amplitude PRECISION GRIP 35.2 ± 5.6%; MEP amplitude POWER GRIP 19.6 ± 3.4%, F = 2.4, P < 0.001) and stimulus-response gradient (SLOPEREST 0.06 ± 0.01; SLOPEPRCISION GRIP 0.15 ± 0.04; SLOPE POWER GRIP 0.07 ± 0.01, P < 0.05) were significantly increased during precision grip. Short interval intracortical inhibition (SICI) was significantly reduced during the precision grip (SICI REST 15.0 ± 2.3%; SICI PRECISION GRIP 9.7 ± 1.5%, SICI POWER GRIP 15.9 ± 2.7%, F = 2.6, P < 0.05). The present study suggests that changes in motor cortex excitability are specific for precision grip, with functional coupling of descending corticospinal pathways controlling thumb and finger movements potentially forming the basis of these cortical changes.

  15. Cuckoo-hawk mimicry? An experimental test.

    Science.gov (United States)

    Davies, N B; Welbergen, J A

    2008-08-07

    The similarity between many Old World parasitic cuckoos (Cuculinae) and Accipiter hawks, in size, shape and plumage, has been noted since ancient times. In particular, hawk-like underpart barring is more prevalent in parasitic than in non-parasitic cuckoos. Cuckoo-hawk resemblance may reflect convergent evolution of cryptic plumage that reduces detection by hosts and prey, or evolved mimicry of hawks by parasitic cuckoos, either for protection against hawk attacks or to facilitate brood parasitism by influencing host behaviour. Here, we provide the first evidence that some small birds respond to common cuckoos Cuculus canorus as if they were sparrowhawks Accipiter nisus. Great tits and blue tits were equally alarmed and reduced attendance at feeders during and after the presentation of mounted specimens of common cuckoos and sparrowhawks, but not in response to control presentations of collared doves or teal. Plumage manipulations revealed that the strong alarm response to cuckoos depended on their resemblance to hawks; cuckoos with barred underparts were treated like hawks, while those with unbarred underparts were treated like doves. However, barring was not the only feature inducing alarm because tits showed similarly strong alarm to barred and unbarred hawks, and little alarm to barred doves. These responses of tits, unsuitable as hosts and hence with no history of cuckoo parasitism, suggest that naive small birds can mistake cuckoos for hawks. Thus, any cuckoo-hawk discrimination by host species is likely to be an evolved response to brood parasitism.

  16. Hawking Radiation and Classical Tunneling

    CERN Document Server

    Tracy, Eugene R

    2015-01-01

    Acoustic waves in fluids undergoing the transition from sub- to supersonic flow satisfy governing equations similar to those for light waves in the immediate vicinity of a black hole event horizon. This acoustic analogy has been used by Unruh and others as a conceptual model for `Hawking radiation.' Here we use variational methods, originally introduced by Brizard for the study of linearized MHD, and ray phase space methods, to analyze linearized acoustics in the presence of background flows. The variational formulation endows the evolution equations with natural Hermitian and symplectic structures that prove useful for later analysis. We derive a $2\\times 2$ normal form governing the wave evolution in the vicinity of the `event horizon.' This shows that the acoustic model can be reduced locally (in ray phase space) to a standard (scalar) tunneling process weakly coupled to a unidirectional non-dispersive wave (the `incoming wave'). Given the normal form, the Hawking `thermal spectrum' can be derived by invok...

  17. Stephen Hawking returns to CERN

    CERN Multimedia

    2009-01-01

    Stephen Hawking visiting the CERN Control Centre.If you happened to pass through Building 4 during the first weeks of September, you might have noticed the name of Stephen Hawking on one of the doors on the second floor, which hosts most of CERN theorists’ offices. Three years after his last visit to CERN, Stephen Hawking gladly accepted the invitation from the University of Geneva to hold a public lecture on the occasion of its 450th anniversary and requested an office at CERN for the length of his stay. The "master of the Universe", as the Geneva University journal dubbed him, attracted over 4000 people to his lecture on "The Creation of the Universe" held on 15 September in the Main Auditorium of Uni Dufour. His more technical colloquium on the same subject at CERN a week earlier, was no less popular and quite "provocative" according to some of the physicists in the audience. With his repeated reference to the "non-need" for a "creating agent" for the Universe, mo...

  18. Examinations of factors influencing toe grip strength.

    Science.gov (United States)

    Soma, Masayuki; Murata, Shin; Kai, Yoshihiro; Nakae, Hideyuki; Satou, Yousuke; Murata, Jun; Miyazaki, Junya

    2016-11-01

    [Purpose] This study examined the relationship between toe grip strength and its associated factors by focusing on factors that were suggested to have a relationship with toe grip strength in previous studies, aiming to clarify the factors influencing the toe grip strength of healthy women. [Subjects and Methods] Twelve healthy young women were selected for this study. Their toe grip strength, angular changes in their ankle joint during toe grip, maximum voluntary contraction activities of the rectus femoris, biceps femoris, and tibialis anterior muscles, and the medial head of the gastrocnemius muscles were measured using electromyography. Their toe curl ability, foot-arch height ratio, and weight were also measured. [Results] Multiple regression analysis demonstrated that the predictors of toe grip strength in the resulting model were foot-arch height ratio and the percentage of integrated electromyography (%IEMG) of the tibialis anterior muscle, as the dependent variables. This reveals that women whose tibialis anterior muscle %IEMG values and foot-arch height ratio are high have greater %IEMG values have greater toe grip strength. [Conclusion] These findings suggest a significant relationship between foot-arch height ratio and toe grip strength, with a reciprocal interaction. These findings further indicate that the risk of falls by the elderly could be decreased if toe grip strength were enhanced, by increasing the height of a low foot-arch with the help of an inserted insole.

  19. Central Limit Theorem for Nonlinear Hawkes Processes

    CERN Document Server

    Zhu, Lingjiong

    2012-01-01

    Hawkes process is a self-exciting point process with clustering effect whose jump rate depends on its entire past history. It has wide applications in neuroscience, finance and many other fields. Linear Hawkes process has an immigration-birth representation and can be computed more or less explicitly. It has been extensively studied in the past and the limit theorems are well understood. On the contrary, nonlinear Hawkes process lacks the immigration-birth representation and is much harder to analyze. In this paper, we obtain a functional central limit theorem for nonlinear Hawkes process.

  20. Conference | From Newton to Hawking and beyond | 28 May

    CERN Multimedia

    2013-01-01

    From Newton to Hawking and beyond: Why disability equality is relevant to the world of particle physics, Dr Tom Shakespeare.    Tuesday, 28 May 2013 - 11.30 am - 1 pm Main Auditorium – Room 500-1-001 Conference organised by the CERN Diversity Programme English with French interpretation According to the recent world report on disability, 15% of the world’s population is disabled.  Among that group could be numbered famous physicists such as Isaac Newton and Paul Dirac, neither of whom could be classed as “neuro-typical”, and Stephen Hawking.  This presentation will provide some basic data about global disability, and the socially imposed barriers which disabled people face.  It will also include some stories about high achieving people with disabilities.  Finally, some practical suggestions will be offered on how to respect and include people with disabilities in the workplace. Tom Shakespeare is a social sci...

  1. Hawking Temperature of Acoustic Black Hole

    Indian Academy of Sciences (India)

    Zhi Kun Xie

    2014-09-01

    Using a new tortoise coordinate transformation, the Hawking radiation of the acoustic black hole was discussed by studying the Klein–Gordon equation of scalar particles in the curve space-time. It was found that the Hawking temperature is connected with time and position on the event horizon.

  2. Introducing Stephen Hawking a graphic guide

    CERN Document Server

    McEvoy, JP

    2014-01-01

    Stephen Hawking is the world-famous physicist. To the public he is a tragic figure - a brilliant scientist and author of the 9 million-copy-selling ""A Brief History of Time"", and yet confined to a wheelchair and almost completely paralysed. This guide explores Hawking's life, and the evolution of his work from his days as a student.

  3. The pair correlation function of spatial Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Torrisi, Giovanni Luca

    2007-01-01

    Spatial Hawkes processes can be considered as spatial versions of classical Hawkes processes. We derive the pair correlation function of stationary spatial Hawkes processes and discuss the connection to the Bartlett spectrum and other summary statistics. Particularly, results for Gaussian fertility...... rates and the extension to spatial Hawkes processes with random fertility rates are discussed....

  4. L'univers clos de Stephen Hawking.

    Science.gov (United States)

    Andrillat, H.

    Einstein had curved space, Hawking will curve time. Hawking's universe is a closed model, a 4-sphere, which encloses its own space and its own time. Nothing exists outside and without any time overlapping this 4-sphere, it cannot have a beginning, an evolution or an end. It only is. But such an absolute existence of this type of universe implies that its 3-dimensional sclices - which are our physical space - cannot have the same absolute state of being. Thus, they are necessarily transitory, with a beginning and an end, in time which is the 4th remaining dimension of the 4-sphere. Hawking absolute universe is the cause of time.

  5. Origin of Hawking Radiation: Firewall or Atmosphere?

    CERN Document Server

    Kim, Wontae

    2016-01-01

    The Unruh vacuum not admitting any outgoing flux at the horizon implies that the origin of the outgoing Hawking radiation would be the atmosphere of a near-horizon quantum region without resort to the firewall; however, the existence of the firewall of superplanckian excitations at the horizon might be supported by the infinite Tolman temperature of the infinitely blueshifted Hawking temperature at the horizon. Using an exactly soluble model, we show that the firewall necessarily emerges out of the Unruh vacuum such that the Tolman temperature in the Unruh vacuum is divergent in essence due to the infinitely blueshifted negative ingoing flux crossing the horizon rather than the outgoing flux. It is also shown that the outgoing Hawking radiation in the Unruh vacuum indeed originates from the atmosphere, not just at the horizon, which is of no relevance to the infinite blueshift. Consequently, we find that the firewall induced from the infinite Tolman temperature and the Hawking radiation coming from the atmosp...

  6. Comment on Hawking radiation and trapping horizons

    CERN Document Server

    Baier, Rudolf

    2015-01-01

    We consider dynamical black hole formation from a collapsing fluid described by a symmetric and flat FRW metric. Using the Hamilton-Jacobi method the local Hawking temperature for the formed trapping/apparent horizon is calculated. The local Hawking temperature depends on the tunneling path, which we take to be along a null direction $(\\Delta s=0)$. We find that the local Hawking temperature depends directly on the equation of state of the collapsing fluid. We argue that Hawking radiation by quantum tunnelling from future inner and future outer trapping horizons is possible. However, only radiation from a space-like dynamical horizon has a chance to be observed by an external observer. Some comparison to existing literature is made.

  7. Swainson's hawk observations Kern NWR 1991 - 1994

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document describes observations of Swainson's Hawks at Kern NWR and Wildwood Road. It also includes a brief discussion of management strategies to promote...

  8. Hawking radiation from quasilocal dynamical horizons

    Indian Academy of Sciences (India)

    Ayan Chatterjee

    2016-02-01

    In completely local settings, we establish that a dynamically evolving spherically symmetric black hole horizon can be assigned a Hawking temperature and with the emission of flux, radius of the horizon shrinks.

  9. Black Holes in Hawking's New Theory

    Institute of Scientific and Technical Information of China (English)

    Carolyn Johnson; 张凯华

    2004-01-01

    @@ Stephan Hawking, the physicist, says he was wrong about his long-held idea about black holes, backing off① a theory that had raised the possibility that the collapsed stars were swallowing information and sending it to alternate② universes.

  10. Hawking radiation from a collapsing quantum shell

    Science.gov (United States)

    Pullin, Jorge; Eyheralde, Rodrigo; Gambini, Rodolfo

    2017-01-01

    We study Hawking radiation from a collapsing shell with uncertainty in its position and momentum. We see there are deviations from the usual spectrum early on in the evolution, tending asymptotically to the usual spectrum plus small corrections.

  11. Hawking's Israel boycott sparks heated response

    Science.gov (United States)

    Dacey, James

    2013-06-01

    The controversial decision by Stephen Hawking to boycott a prominent conference in Jerusalem in protest against the policies of the Israeli government has provoked strong responses from academics and commentators.

  12. Amplifying the Hawking Signal in BECs

    Directory of Open Access Journals (Sweden)

    Roberto Balbinot

    2014-01-01

    Full Text Available We consider simple models of Bose-Einstein condensates to study analog pair-creation effects, namely, the Hawking effect from acoustic black holes and the dynamical Casimir effect in rapidly time-dependent backgrounds. We also focus on a proposal by Cornell to amplify the Hawking signal in density-density correlators by reducing the atoms’ interactions shortly before measurements are made.

  13. Ferruginous hawks on the Yakima Training Center

    Energy Technology Data Exchange (ETDEWEB)

    Mazaika, R.; Cadwell, L.L.

    1994-07-01

    Habitat quality for ferruginous hawks (Buteo regalis) is largely determined by availability of nest sites and adequate prey base. A limitation of one of these will limit the number of hawks in an area. In general, ferruginous hawks are adaptable to various nesting substrates and will nest in proximity to other closely related sympatric species (e.g., red-tailed hawk, Swainson`s hawk). This analysis focused on an assessment of prey base availability and habitat disturbance in the vicinity of historic nest sites and small mammal trap sites on the Yakima Training Center (YTC) in Washington State. The primary ground-disturbing activities on the YTC are associated with military training, fire, and grazing. In addition to the direct effect these activities can have on ferruginous hawks, indirect effects may result from changes in composition, density, and structure of vegetation that subsequently alter faunal population numbers and species diversity. A summary of results of small mammal trapping, population estimation, vegetative analysis and disturbance rating at seven trap sites during the time period of June through August of 1993 are presented.

  14. Hand-grip isometric strength in judo

    Directory of Open Access Journals (Sweden)

    Juan G Bonitch-Góngora

    2014-02-01

    Full Text Available The grip is an important technical and tactical aspect through which the judokas dominate the adversary, hindering the application of appropriate techniques and favoring their own attack. The judokas must have high levels of isometric force and endurance to this type of force on the gripping muscles of the forearms, as one of the key aspects for success. This article reviews the grip muscular strength and endurance profiles of judokas of different groups (gender, age and competitive level. In general, the peak isometric strength of elite judokas has not changed in the last 40 years and is similar to that reached by non-elite judokas or even registered in large populations. This indicate that the evaluation of the isometric hand grip endurance may be a more relevant parameter than the peak isometric force in judokas, as during the bouts the grip must be maintained for relatively long periods of time and the maximum force cannot be maintained for long. However there are few studies on the ability to resist successive isometric handgrip stress in judokas.

  15. Hawking radiation via tunneling from the spacetime of a spinning cosmic string black holes

    CERN Document Server

    Jusufi, Kimet

    2015-01-01

    In this paper, we study Hawking radiation as a massless particles tunneling process across the event horizon from the Schwarzschild and Reissner-Nordstr\\"om black holes pierced by an infinitely long spinning cosmic string and a global monopole. Applying the WKB approximation and using a generalized Painlev\\'e line element for stationary axisymmetric spacetimes, also by taking into account that the ADM mass of the black hole decreases due to the presence of topological defects, it is shown that the Hawking temperature remains unchanged for these black holes. The tunneling of charged massive particles from Reissner-Nordstr\\"om black holes is also studied, in both cases the tunneling rate is related to the change of the Bekenstein-Hawking entropy. The results extend the work of Parikh and Wilczek and are consistent with an underlying unitary theory.

  16. [Grip strength changes in familial amyloidotic polyneuropathy].

    Science.gov (United States)

    Tomás, Maria Teresa; Santa-Clara, Helena; Monteiro, Estela; Carolino, Elizabete; Freire, António; Barroso, Eduardo

    2010-01-01

    Familial amiloidotic polyneuropathy (FAP) is an autossomical and dominant neurodegenerative disease related with systemic deposition of amyloid fibre mainly on peripheral nervous system. Clinically, is translated by an autonomous sensitive-motor polyneuropathy with beginning nearly always in foot, involving subsequently the hands. Until now, the unique available treatment for FAP disease is liver transplantation requiring medication that negatively affect muscle metabolism and force production mechanism. To our knowledge there are no quantitative characterizations of peak force in FAP patients or any comparison with healthy people. This knowledge will be extremely important to verify clinical and functional evolution of this disease and eventually prescribe an effective rehabilitation program. The purpose of this study was to analyse and compare levels of hand grip strength (peak force and endurance) in FAP patients with (FAPTx) or without (FAPNTx) a liver transplant with a group of healthy people (GC). The total sample of individuals where two hundred and six, assigned in 3 groups: 59 patients PAFNTx (23 males, 36 female; age 35 ± 8 years); 90 patients PAFTx (53 males, 37 females; age 34 ± 8 years) e 62 healthy persons (GC) (30 males, 32 females; age 33 ± 9 years). Grip strength was assessed by a portable grip dynamometer E-link (Biometrics Ltd, UK). All measurements were taken on standardized positions with standardized orders. The value noted to peak force was classified according to American College of Sports Medicine norms for grip strength. The 3 groups are differents (p < 0,05) for weigth, body mass index (BMI) and grip strength in both hands and endurance for left hand. Negative correlations between age and grip strength were found for PAFNTx and PAFTx but not for GC. According to our results FAP patients have lower values for grip strength in both hands than healthy subjects and consequently a worse classification in ACSM norms. Most patients present

  17. Bekenstein-Hawking Entropy as Entanglement Entropy

    CERN Document Server

    Feng, Yu-Lei

    2015-01-01

    We show that the Bekenstein-Hawking entropy $S_{BH}$ should be treated as an entanglement entropy, provided that the formation and evaporation of a black hole can be described by quantum unitary evolutions. To confirm this statement, we derive statistical mechanics from quantum mechanics effectively by means of open quantum systems. Then a new definition of Boltzmann entropy for a quantum closed system is given to count microstates in a way consistent with the superposition principle. In particular, this new Boltzmann entropy is a constant that depends only on the dimension of the system's relevant Hilbert subspace. Based on this new definition, some kind of "detailed balance" condition is obtained to stabilize the thermal equilibrium between two macroscopic subsystems within a larger closed system. However, the required "detailed balance" condition between black hole and matter would be broken, if the Bekenstein-Hawking entropy was treated as Boltzmann entropy together with the Hawking temperature as thermal...

  18. Hawking radiation in the kappa-spacetime

    CERN Document Server

    Harikumar, E

    2016-01-01

    In this paper, we analyze the Hawking radiation of kappa-deformed Schwarzchild black hole and obtain the deformed Hawking temperature. For this, we first derive deformed metric for the kappa-spacetime, which in the generic case, is not a symmetric tensor and also has a momentum dependence. We show that the Schwarzchild metric obtained in the kappa-deformed spacetime has a dependence on energy. We use the fact that the deformed metric is conformally flat in the 1+1 dimensions, to solve the kappa-deformed Klein-Gordon equation in the background of the Schwarzchild metric. The method of Boguliobov coefficients is then used to calculate the thermal spectrum of kappa-deformed-Schwarzchild black hole and show that the Hawking temperature is modified by the non-commutativity of the kappa-spacetime.

  19. Hawking radiation without black hole entropy

    CERN Document Server

    Visser, M

    1998-01-01

    In this Letter I point out that Hawking radiation is a purely kinematic effect that is generic to Lorentzian geometries. Hawking radiation arises for any test field on any Lorentzian geometry containing an event horizon regardless of whether or not the Lorentzian geometry satisfies the dynamical Einstein equations of general relativity. On the other hand, the classical laws of black hole mechanics are intrinsically linked to the Einstein equations of general relativity (or their perturbative extension into either semiclassical quantum gravity or string-inspired scenarios). In particular, the laws of black hole thermodynamics, and the identification of the entropy of a black hole with its area, are inextricably linked with the dynamical equations satisfied by the Lorentzian geometry: entropy is proportional to area (plus corrections) if and only if the dynamical equations are the Einstein equations (plus corrections). It is quite possible to have Hawking radiation occur in physical situations in which the laws...

  20. Breeding ecology of ferruginous hawks, Swainson’s hawks, and northern harriers in south-central North Dakota : Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Project proposal for research survey to document the breeding ecology of ferruginous hawks, Swainson’s hawk, and northern harrier in Kulm Wetland Management District...

  1. Breeding ecology of ferruginous hawks, Swainson's hawks, and northern harriers in south-central North Dakota : Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Final report of research survey to document the breeding ecology of ferruginous hawks, Swainson’s hawk, and northern harrier in Kulm Wetland Management District...

  2. Breeding ecology of ferruginous hawks, Swainson's hawks, and northern harriers in south-central North Dakota : Final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Final report of research survey to document the breeding ecology of ferruginous hawks, Swainsons hawk, and northern harrier in Kulm Wetland Management District WMD...

  3. Evidence of hawking (falconry) from bird and mammal bones

    NARCIS (Netherlands)

    Prummel, W.

    1997-01-01

    This paper deals with the archaeozoological and archaeological evidence for hawking, or falconry. The methods and history of hawking in Europe are described, after which five types of evidence for hawking are discussed. These are illustrated with material from the Slavonic stronghold of Oldenburg in

  4. Evidence of hawking (falconry) from bird and mammal bones

    NARCIS (Netherlands)

    Prummel, W.

    1997-01-01

    This paper deals with the archaeozoological and archaeological evidence for hawking, or falconry. The methods and history of hawking in Europe are described, after which five types of evidence for hawking are discussed. These are illustrated with material from the Slavonic stronghold of Oldenburg in

  5. Temperature limit values for gripping cold surfaces

    NARCIS (Netherlands)

    Malchaire, J.; Geng, Q.; Den Hartog, E.; Havenith, G.; Holmer, I.; Piette, A.; Powell, S.L.; Rintamäki, H.; Rissanen, S.

    2002-01-01

    Objectives. At the request of the European Commission and in the framework of the European Machinery Directive, research was conducted jointly in five different laboratories to develop specifications for surface temperature limit values for the gripping and handling of cold items. Methods. Four

  6. Temperature limit values for gripping cold surfaces

    NARCIS (Netherlands)

    Malchaire, J.; Geng, Q.; Den Hartog, E.; Havenith, G.; Holmer, I.; Piette, A.; Powell, S.L.; Rintamäki, H.; Rissanen, S.

    2002-01-01

    Objectives. At the request of the European Commission and in the framework of the European Machinery Directive, research was conducted jointly in five different laboratories to develop specifications for surface temperature limit values for the gripping and handling of cold items. Methods. Four hund

  7. Grip-Pattern Recognition for Smart Guns

    NARCIS (Netherlands)

    Kauffman, J.A.; Bazen, A.M.; Gerez, S.H.; Veldhuis, R.N.J.

    2003-01-01

    This paper describes the design, implementation and evaluation of a user-verification system for a smart gun, which is based on grip-pattern recognition. An existing pressure sensor consisting of an array of 44 x 44 piezoresistive elements has been used. An interface has been developed to acquire pr

  8. The GRIP method for collaborative roadmapping workshops

    DEFF Research Database (Denmark)

    Piirainen, Kalle

    2015-01-01

    Technology roadmapping is a well-known tool for technology management, but practical advice for facilitating collaborative roadmapping workshops is relatively scarce. To cater for this need, we have designed a method for collaborative roadmapping, dubbed the GRIP method, for facilitating group work...

  9. Stephen Hawking and the universe a biography

    CERN Document Server

    Sztajnkrycer, Ben

    2012-01-01

    ABOUT THE BOOK Stephen William Hawking is arguably the most famous scientist since Albert Einstein. He is a theoretical physicist, applied mathematician, and cosmologist, but he is best known to non-scientists as the author of "A Brief History of Time," his best-selling book that unraveled the origins of the universe. His fame is so far-reaching that he has appeared on such popular entertainment as "Star Trek: The Next Generation" and "Late Night with Conan O'Brien." He has even been animated as a character on "The Simpsons." Hawking is also well known for being the longest-living survivor

  10. ANALYSIS OF POWER GRIP AND PINCH GRIP AMONG HEALTH CARE PROFESSIONALS

    Directory of Open Access Journals (Sweden)

    Zakariya M P

    2016-02-01

    Full Text Available Background: Grip and pinch strength are commonly employed indices of strength used in hand evaluations. Pinch grip and power grip strengths are used as indices of strength in hand therapy assessments. For all professions grip strength is an important criterion to be successful in their profession. Such phenomena may be explained by differences in nature of work, working environment, and objects workers handle. Method: 200 healthy subjects, satisfying the selection criteria were included and assessed with standardized procedure for power grip and pinch grip (lateral pinch, pad-pad, and tip-tip strength. They were divided in four groups, 50 group each according to profession i.e. medical surgeons, dentist, physiotherapists and nurses. Results: The mean power grip strength shows highly significant difference between medical vs. dental (p>0.01 and medical vs. physiotherapy group (p> 0.05 .The mean lateral pinch strength shows there is highly significant difference (p< 0.001 between dental vs. nursing profession and dental vs. physiotherapy group. No significant difference among other groups. The mean pad-pad pinch strength shows there is significant difference between dental vs. nursing (p< 0.05 and dental vs physiotherapy group (p< 0.05. The mean Tip-Tip pinch strength shows there is significant difference between dental vs nursing profession(p< 0.05 and dental vs. physiotherapy(p< 0.05. No significant different among other groups. Conclusion: Surgeons have highest power grip strength followed by Nursing, Physiotherapy and Dental professionals. Dentists have the maximum pinch strength in all three positions, followed by Surgeons, Nurses and Physiotherapists. Surgeons have maximum pinch strength next to Dentists.

  11. Registration of hand-grip pattern in smart gun

    NARCIS (Netherlands)

    Shang, X.; Veldhuis, R.N.J.

    2006-01-01

    Secure Grip1 focuses on the development of a hand-grip pattern recognition system, as part of a smart gun. It is intended for use by the police. We collected the hand-grip data from police officers in three sessions in a row with time intervals in between. If data for training and testing come from

  12. Effect of elbow flexion, forearm rotation and upper arm abduction on MVC grip and grip endurance time.

    Science.gov (United States)

    Farooq, Mohd; Khan, Abid Ali

    2012-01-01

    This experiment was designed to know the effect of upper limb postural deviations on grip strength and grip endurance time. A full factorial design of experiment, i.e., 3 (0°, 45°, 90° abduction angles of upper arm) × 3 (45°, 90°, 135° angles of elbow flexion) × 3 (0°, -60° prone, +60° supine angles of forearm rotation) was used to find the effect of 27 combinations of postures on maximum voluntary contraction (MVC) grip strength and grip endurance time. The results showed that none of the main factors were significant on MVC grip, although there was a change in MVC grip. Grip endurance time significantly decreased with an increase in upper arm abduction. Also, grip endurance significantly increased with the elbow flexion angle and decreased with forearm rotation from neutral. These data will help designers and engineers to improve the workplace and tools to reduce the risk of injuries.

  13. Variability of grip kinetics during adult signature writing.

    Directory of Open Access Journals (Sweden)

    Bassma Ghali

    Full Text Available Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20 adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of 1.2±0.4% in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.

  14. Variability of grip kinetics during adult signature writing.

    Science.gov (United States)

    Ghali, Bassma; Thalanki Anantha, Nayanashri; Chan, Jennifer; Chau, Tom

    2013-01-01

    Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20) adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image) was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC) of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height) or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of 1.2±0.4% in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.

  15. On the Mutual Information in Hawking Radiation

    CERN Document Server

    Iizuka, Norihiro

    2013-01-01

    We compute the mutual information of two Hawking particles emitted consecutively by an evaporating black hole. Following Page, we find that the mutual information is of order exp(-S) where S is the entropy of the black hole. We speculate on implications for black hole unitarity, in particular on a possible failure of locality at large distances.

  16. Hawking radiation conference, book of proceedings

    CERN Document Server

    Mersini-Houghton, Laura

    2016-01-01

    Proceedings of the 'Hawking Radiation' conference in Stockholm, Sweden 2015. It includes a link to the video recording of the conference and all the talks, discussions, and communications, that took place during the week of the conference . We hope the recorded discussions will be helpful, especially to the current and future young researchers and students.

  17. Stephen Hawking a life in science

    CERN Document Server

    White, Michael

    1992-01-01

    This biography of the author of "A Brief History of Time", pays particular attention to Hawking's considerable scientific achievement, as well as to the tragic progress of his illnesss and his extraordinary will to survive and to continue working despite major progressive handicap.

  18. Origin of Hawking radiation: firewall or atmosphere?

    Science.gov (United States)

    Kim, Wontae

    2017-02-01

    The Unruh vacuum not admitting any outgoing flux at the horizon implies that the origin of the outgoing Hawking radiation is the atmosphere of a near-horizon quantum region without resort to the firewall; however, the existence of the firewall of superplanckian excitations at the horizon can be supported by the infinite Tolman temperature at the horizon. In an exactly soluble model, we explicitly show that the firewall necessarily emerges out of the Unruh vacuum so that the Tolman temperature in the Unruh vacuum is divergent in essence due to the infinitely blueshifted negative ingoing flux crossing the horizon rather than the outgoing flux. We also show that the outgoing Hawking radiation in the Unruh vacuum indeed originates from the atmosphere, not just at the horizon, which is of no relevance to the infinite blueshift. Consequently, the firewall from the infinite Tolman temperature and the Hawking radiation from the atmosphere turn out to be compatible, once we waive the claim that the Hawking radiation in the Unruh vacuum originates from the infinitely blueshifted outgoing excitations at the horizon.

  19. Stephen Hawking, Black Holes and Quantum Theory

    Institute of Scientific and Technical Information of China (English)

    CatyWeaver; 朱汉昌

    2004-01-01

    Recently, the physicist Stephen Hawking(斯蒂芬·霍金)had an announcement that made news around the world. Mr. Hawking is the Lucasian.Professor of Mathematics at the University of Cambridge in England. He was in Ireland at the Seventeenth International Conference on General Relativity. This was his announcement: he has changed his mind about black holes.

  20. Krein Quantization Approach to Hawking Radiation

    CERN Document Server

    Pejhan, H

    2014-01-01

    We prove that in the context of Krein method, by applying the results of the accelerated-mirror to a black hole, one can recover the result obtained by Hawking for black hole radiation even considering the fact that vacuum expectation value of the energy-momentum tensor of the free theory is zero.

  1. On the stringy Hartle-Hawking state

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Israel, Roy [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel); Giveon, Amit [Racah Institute of Physics, The Hebrew University,Jerusalem, 91904 (Israel); Itzhaki, Nissan; Liram, Lior [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel)

    2016-03-03

    We argue that non-perturbative α{sup ′} stringy effects render the Hartle-Hawking state associated with the SL(2)/U(1) eternal black hole singular at the horizon. We discuss implications of this observation on firewalls in string theory.

  2. Optimal work-rest cycles for an isometric intermittent gripping task as a function of force, posture and grip span.

    Science.gov (United States)

    Eksioglu, Mahmut

    2006-02-10

    The aim of this study was to investigate the maximum acceptable contraction frequencies (i.e. work-rest cycles) for an isometric-intermittent handgrip task as a function of grip span, applied force and shoulder posture using psychophysical and physiological approaches. Twelve healthy males served as subjects. The three grip spans investigated were the optimal, 2 cm narrower than the optimal, and 2 cm wider than the optimal. The grip force levels studied were 15% and 30% of maximum voluntary grip force and the two shoulder postures were 25 degrees flexion and 30 degrees abduction. The psychophysical results indicate that subjects work faster with the narrower grip span at 15% of maximum voluntary grip force level in comparison to working with the optimal and the wider spans. However, when the task required 30% of maximum grip force level, the subjects worked faster with the optimal grip span. These findings were supported by the results of electromyography, heart rate, blood pressure and perceived discomfort. The study suggests that grip span of a tool is an important factor to be considered in predicting optimal work-rest cycles for hand grip tasks, and the optimum setting of grip span of the hand-tool depends on the required task force level. That is, the optimality is relative rather than absolute. In addition, it appears that weaker subjects can work at a higher rate than stronger ones at the same relative force level.

  3. ASSESSMENT OF GRIP FORCE CONTROL IN PATIENTS WITH MUSCULAR DYSTROPHY

    Directory of Open Access Journals (Sweden)

    Gregorij Kurillo

    2004-12-01

    Full Text Available Background. The majority of hand functionality tests are based on qualitative assessment which largely depends on the experience of the therapist. Computer-assisted methods can provide more objective and accurate measurements of the grip force and other parameters related to grasping.Methods. We analysed the grip force control in 12 patients with muscular dystrophy using the tracking system developed. The system consists of a grip-measuring device with endobjects assessing the force applied in different grips. The device was used as input to a tracking task where the patient applied the grip force according to the visual feedback from the computer screen. Each patient performed two tasks which consisted of tracking a ramp and sinus target.Results. We analysed the maximal grip force as assessed in the ramp task and the tracking accuracy of the sinus task. The results are compared among five different grips (cylindrical, lateral, palmar, pinch and spherical grip, applied with dominant and non-dominant hand. The results show no significant difference in tracking accuracy between the dominant and non-dominant hand.Conclusions. The results obtained in tracking the ramp target showed that the method could be used for the assessment of the muscle fatigue, providing quantitative information on muscle capacity. The results of the sinus-tracking task showed that the method can evaluate the grip force control in different types of grips, providing information on hand dexterity, muscle activation patterns or tremor.

  4. Bekenstein-Hawking entropy from Criticality

    CERN Document Server

    Bhattacharya, Swastik

    2014-01-01

    Vacuum Einstein equations when projected on to a black hole horizon is analogous to the dynamics of fluids. In this work we address the question, whether certain properties of semi-classical black holes could be holographically mapped into properties of (2 + 1)-dimensional fluid living on the horizon. In particular, we focus on the statistical mechanical description of the horizon-fluid that leads to Bekenstein-Hawking entropy. Within the paradigm of Landau mean field theory and existence of a condensate at a critical temperature, we explicitly show that Bekenstein-Hawking entropy and other features of black hole thermodynamics can be recovered from the statistical modelling of the fluid. We also show that a negative cosmological constant acts like an external magnetic field that induces order in the system leading to the appearance of a tri-critical point in the phase diagram.

  5. Live trapping of hawks and owls

    Science.gov (United States)

    Stewart, R.E.; Cope, J.B.; Robbins, C.S.

    1945-01-01

    1. Hawks of six species (80 individuals) and owls of five species (37 individuals) were trapped for banding from November 1, 1943, to. May 26,1944. 2. In general, pole traps proved better than hand-operated traps or automatic traps using live bait. 3. Verbail pole traps proved very efficient, and were much more humane than padded steel traps because they rarely injured a captured bird. 4: Unbaited Verbail traps took a variety of raptors, in rough proportion to their local abundance, although slightly more of beneficial species were caught than of harmful types. 5. Hawks and owls were retrapped more readily in Verbail traps than in other types tried. 6. The number of song birds caught in Verbail traps was negligible. 7. Crows and vultures were not taken in Verbail traps, but possibly could be caught with bait.

  6. A hawk is ready for flight

    Science.gov (United States)

    2000-01-01

    This Broad-Winged Hawk is ready for flight from its perch on a utility pole at Kennedy Space Center. This hawk's habitat is chiefly deciduous woodland, ranging from southern Canada south throughout the eastern United States, including a small area of Central Florida. It winters in tropical South America. The Center shares a boundary with the Merritt Island National Wildlife Refuge, a haven and habitat for more than 331 species of birds. The Refuge encompasses 92,000 acres that are also a habitat for 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  7. Hawking radiation and secularly growing loop corrections

    CERN Document Server

    Akhmedov, Emil T; Popov, Fedor K

    2016-01-01

    We study the expectation value of the energy momentum tensor during thin shell collapse for a massive, real, scalar field theory. At tree-level, we find thermal, Hawking-type, behaviour for the energy flux. Using the Schwinger-Keldysh technique, we calculate two-loop corrections to the tree-level correlation functions and show that they exhibit secular growth, suggesting the breakdown of the perturbation theory.

  8. Casimir Effect, Hawking Radiation and Trace Anomaly

    CERN Document Server

    Setare, M R

    2001-01-01

    The Casimir energy for massless scalar field of two parallel conductor, in two dimensional Schwarzchild black hole background, with Dirichlet boundary conditions is calculated by making use of general properties of renormalized stress tensor. We show that vacuum expectation value of stress tensor can be obtain by Casimir effect, trace anomaly and Hawking radiation. Four-dimensional of this problem, by this method, is under progress by this author.

  9. Entropy/information flux in Hawking radiation

    CERN Document Server

    Alonso-Serrano, Ana

    2015-01-01

    Blackbody radiation contains (on average) an entropy of $3.9\\pm2.5$ bits per photon. This applies not only to the proverbial case of "burning a lump of coal", but also to the Hawking radiation from both analogue black holes and general relativistic black holes. The flip side of this observation is the information budget: If the emission process is unitary, (as it certainly is for normal physical/chemical burning, and also for the Hawking emission from analogue black holes), then this entropy is exactly compensated by the "hidden information" in the correlations. We shall now extend this argument to the Hawking radiation from general relativistic black holes, (where previous discussion is both heated and inconclusive), demonstrating that the assumption of unitarity leads to a perfectly reasonable entropy/information budget without any hint of a "firewall". The assumption of unitarity instead has a different implication --- the horizon (if present) cannot be an *event* horizon, it must be an *apparent/trapping*...

  10. Hawking radiation a particle physics perspective

    CERN Document Server

    Visser, M

    1993-01-01

    It has recently become fashionable to regard black holes as elementary particles. By taking this suggestion seriously it is possible to cobble together an elementary particle physics based estimate for the decay rate $(\\hbox{black hole})_i \\to (\\hbox{black hole})_f + (\\hbox{massless quantum})$. This estimate of the spontaneous emission rate contains two free parameters which may be fixed by demanding that the high energy end of the spectrum of emitted quanta match a blackbody spectrum at the Hawking temperature. The calculation, though technically trivial, has important conceptual implications: (1) The existence of Hawking radiation from black holes is ultimately dependent only on the fact that massless quanta (and all other forms of matter) couple to gravity. (2) The thermal nature of the Hawking spectrum depends only on the fact that the number of internal states of a large mass black hole is enormous. (3) Remarkably, the resulting formula for the decay rate gives meaningful answers even when extrapolated t...

  11. Fatal pox infection in a rough-legged hawk

    Science.gov (United States)

    Pearson, G.L.; Pass, D.A.; Beggs, E.C.

    1975-01-01

    Natural pox infection occurred in a free-living rough-legged hawk (Buteo lagopus) in northeastern North Dakota. Gross, histological and electron microscopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (Buteo jamaicensis) but not in great horned owls (Bubo virginianus) following inoculation with case material. Death of the rough-legged hawk was attributed to starvation resulting from inability to capture prey and to blood loss from foot lesions.

  12. Electric Shock Injuries in a Harris's Hawk Population

    OpenAIRE

    Dwyer, James F.

    2006-01-01

    Electrocution may be an important agent of mortality in many raptor populations, and has been implicated as a contributing factor in the endangerment of some species. In Tucson, Arizona U.S.A. the electrocution of Harris's Hawks (Parabuteo unicinctus) was reported in both the 1980s and 1990s. The latter report also described Harris's Hawks that survived electric shock injuries. From February 2003-May 2004, I captured and examined wild Harris's Hawks in Tucson to investigate whether electric s...

  13. Proximal arm kinematics affect grip force-load force coordination

    OpenAIRE

    Vermillion, Billy C.; Lum, Peter S; Lee, Sang Wook

    2015-01-01

    During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct...

  14. Microspine Gripping Mechanism for Asteroid Capture

    Science.gov (United States)

    Merriam, Ezekiel G.; Berg, Andrew B.; Willig, Andrew; Parness, Aaron; Frey, Tim; Howell, Larry L.

    2016-01-01

    This paper details the development and early testing of a compliant suspension for a microspine gripper device for asteroid capture or micro-gravity percussive drilling. The microspine gripper architecture is reviewed, and a proposed microspine suspension design is presented and discussed. Prototyping methods are discussed, as well as testing methods and results. A path forward is identified from the results of the testing completed thus far. Key findings include: the microspine concept has been established as a valid architecture and the compliant suspension exhibits the desired stiffness characteristics for good gripping behavior. These developments will aid in developing the capability to grasp irregularly shaped boulders in micro-gravity.

  15. Notes on breeding sharp-shinned hawks and Cooper’s hawks in Barnwell County, South Carolina.

    Energy Technology Data Exchange (ETDEWEB)

    Vukovich, Mark; Kilgo, John, C.

    2009-07-01

    Abstract - Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooper’s Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned Hawk in Barnwell County, SC and the first report of Sharp-shinned Hawks preying upon Red-headed Woodpeckers. Thirteen of 93 (13.9 %) woodpeckers were killed by accipiters in the summers of 2006 and 2007. Large, contiguous forests managed for Picoides borealis (Red-cockaded Woodpeckers) may be used by breeding Sharp-shinned Hawks. The bright plumage, loud calls, and behavior of Red-headed Woodpeckers, particularly during the nestling stage, may make them conspicuous prey for accipiters.

  16. Analysis list: Grip1 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Grip1 Blood + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Grip1.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Grip1.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Gri...p1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Grip1.Blood.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Blood.gml ...

  17. Adaptive Human Control Gains During Precision Grip

    Directory of Open Access Journals (Sweden)

    Erik D. Engeberg

    2013-03-01

    Full Text Available Eight human test subjects attempted to track a desired position trajectory with an instrumented manipulandum (MN. The test subjects used the MN with three different levels of stiffness. A transfer function was developed to represent the human application of a precision grip from the data when the test subjects initially displaced the MN so as to learn the position mapping from the MN onto the display. Another transfer function was formed from the data of the remainder of the experiments, after significant displacement of the MN occurred. Both of these transfer functions accurately modelled the system dynamics for a portion of the experiments, but neither was accurate for the duration of the experiments because the human grip dynamics changed while learning the position mapping. Thus, an adaptive system model was developed to describe the learning process of the human test subjects as they displaced the MN in order to gain knowledge of the position mapping. The adaptive system model was subsequently validated following comparison with the human test subject data. An examination of the average absolute error between the position predicted by the adaptive model and the actual experimental data yielded an overall average error of 0.34mm for all three levels of stiffness.

  18. Forearm posture and grip effects during push and pull tasks.

    Science.gov (United States)

    Di Domizio, Jennifer; Keir, Peter J

    2010-03-01

    Direction of loading and performance of multiple tasks have been shown to elevate muscle activity in the upper extremity. The purpose of this study was to evaluate the effects of gripping on muscle activity and applied force during pushing and pulling tasks with three forearm postures. Twelve volunteers performed five hand-based tasks in supinated, neutral and pronated forearm postures with the elbow at 90 degrees and upper arm vertical. All tasks were performed with the right (dominant) hand and included hand grip alone, push and pull with and without hand grip. Surface EMG from eight upper extremity muscles, hand grip force, tri-axial push and pull forces and wrist angles were recorded during the 10 s trials. The addition of a pull force to hand grip elevated activity in all forearm muscles (all p push with grip tasks, forearm extensor muscle activity tended to increase when compared with grip only while flexor activity tended to decrease. Forearm extensor muscle activity was higher with the forearm pronated compared with neutral and supinated postures during most isolated grip tasks and push or pull with grip tasks (all p push and pull forces could act to assist in creating grip force, forearm muscle activity generally decreased. These results provide strategies for reducing forearm muscle loading in the workplace. STATEMENT OF RELEVANCE: Tools and tasks designed to take advantage of coupling grip with push or pull actions may be beneficial in reducing stress and injury in the muscles of the forearm. These factors should be considered in assessing the workplace in terms of acute and cumulative loading.

  19. UH-60M Black Hawk Helicopter (UH-60M Black Hawk)

    Science.gov (United States)

    2016-12-01

    Strategy, and the National Defense Strategy. The UH-60M Black Hawk is a digital networked platform with greater range and lift to support maneuver...Critical All All Survivability IR Signature N/A Existing Existing Existing Existing Aircraft Survivability Equipment N/A Existing Existing Existing

  20. Time dependence of Hawking radiation entropy

    Science.gov (United States)

    Page, Don N.

    2013-09-01

    If a black hole starts in a pure quantum state and evaporates completely by a unitary process, the von Neumann entropy of the Hawking radiation initially increases and then decreases back to zero when the black hole has disappeared. Here numerical results are given for an approximation to the time dependence of the radiation entropy under an assumption of fast scrambling, for large nonrotating black holes that emit essentially only photons and gravitons. The maximum of the von Neumann entropy then occurs after about 53.81% of the evaporation time, when the black hole has lost about 40.25% of its original Bekenstein-Hawking (BH) entropy (an upper bound for its von Neumann entropy) and then has a BH entropy that equals the entropy in the radiation, which is about 59.75% of the original BH entropy 4πM02, or about 7.509M02 ≈ 6.268 × 1076(M0/Msolar)2, using my 1976 calculations that the photon and graviton emission process into empty space gives about 1.4847 times the BH entropy loss of the black hole. Results are also given for black holes in initially impure states. If the black hole starts in a maximally mixed state, the von Neumann entropy of the Hawking radiation increases from zero up to a maximum of about 119.51% of the original BH entropy, or about 15.018M02 ≈ 1.254 × 1077(M0/Msolar)2, and then decreases back down to 4πM02 = 1.049 × 1077(M0/Msolar)2.

  1. Algorithm design for grip-pattern verification in smart gun

    NARCIS (Netherlands)

    Shang, X.; Veldhuis, R.N.J.; Bazen, A.M.; Ganzevoort, W.P.T.

    2005-01-01

    The Secure Grip project1 focuses on the development of a hand-grip pattern recognition system, as part of the smart gun. Its target customer is the police. To explore the authentication performance of this system, we collected data from a group of police officers, and made authentication simulations

  2. Biometric verification based on grip-pattern recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond; Bazen, Asker; Kauffman, Joost; Hartel, Pieter

    2004-01-01

    This paper describes the design, implementation and evaluation of a user-verification system for a smart gun, which is based on grip-pattern recognition. An existing pressure sensor consisting of an array of 44 £ 44 piezoresistive elements is used to measure the grip pattern. An interface has been d

  3. Biometric verification based on grip-pattern recognition

    NARCIS (Netherlands)

    Veldhuis, Raymond N.J.; Bazen, A.M.; Kauffman, J.A.; Hartel, Pieter H.; Delp, Edward J.; Wong, Ping W.

    This paper describes the design, implementation and evaluation of a user-verification system for a smart gun, which is based on grip-pattern recognition. An existing pressure sensor consisting of an array of 44 x 44 piezoresistive elements is used to measure the grip pattern. An interface has been

  4. Algorithm Design for Grip-Pattern Verification in Smart Gun

    NARCIS (Netherlands)

    Shang, X.; Veldhuis, Raymond N.J.; Bazen, A.M.; Ganzevoort, W.P.T.

    2005-01-01

    The Secure Grip project1 focuses on the development of a hand-grip pattern recognition system, as part of the smart gun. Its target customer is the police. To explore the authentication performance of this system, we collected data from a group of police officers, and made authentication simulations

  5. Grip-pattern recognition: Applied to a smart gun

    NARCIS (Netherlands)

    Shang, X.

    2008-01-01

    In our work the verification performance of a biometric recognition system based on grip patterns, as part of a smart gun for use by the police ocers, has been investigated. The biometric features are extracted from a two-dimensional pattern of the pressure, exerted on the grip of a gun by the hand

  6. Grip-pattern verification for a smart gun

    NARCIS (Netherlands)

    Shang, X.; Groenland, J.P.J.; Groenland, J.P.J.; Veldhuis, Raymond N.J.

    In the biometric verification system of a smart gun, the rightful user of the gun is recognized based on grip-pattern recognition. It was found that the verification performance of grip-pattern recognition degrades strongly when the data for training and testing the classifier, respectively, have

  7. Normative data on functional grip strength of elderly in Singapore.

    Science.gov (United States)

    Mat Jais, Ita Suzana; Chan, Kai Li; Loke, Mun Kitt Austin; Abdul Rahim, Saleem; Tay, Shian Chao

    2017-02-21

    Cross-sectional study for clinical measurement. Most daily tasks require individuals to exert grip strength with torque, which can be challenging for elderly as their strength diminishes with age. We postulate that to assess the functional capacity of an individual, it is important to evaluate the functional grip strength instead of the maximal static grip strength. The objective of this cross-sectional study is to establish normative data for the functional grip strength of elderly aged 60 years and older in the Singapore population. In this study, 233 healthy subjects aged 60 years and older were recruited. Using a custom-made hand strength measurement device, the following measurements were recorded: grip strength at neutral position, grip strength with resistive pronation torque, and grip strength with resistive supination torque. Grip strengths measured for both genders decreased by 13% and 16% for males and females respectively, when pronation torque was exerted, and with supination torque, the strength decreased by 18% and 17% for males and females respectively. Normative data for the elderly population in Singapore had been established. The findings from this study can complement the existing ergonomic hand data in designing better assistive tools to improve the independent living of elderly. NA. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  8. A quasiperiodic Gibbons-Hawking metric and spacetime foam

    CERN Document Server

    Nergiz, S; Nergiz, Serdar; Saclioglu, Cihan

    1995-01-01

    We present a quasiperiodic self-dual metric of the Gibbons--Hawking type with one gravitational instanton per spacetime cell. The solution, based on an adaptation of Weierstrassian \\zeta and \\sigma functions to three dimensions, conforms to a definition of spacetime foam given by Hawking.

  9. Hawking Radiation from Plane Symmetric Black Hole Covariant Anomaly

    Institute of Scientific and Technical Information of China (English)

    ZENG Xiao-Xiong; HAN Yi-Wen; YANG Shu-Zheng

    2009-01-01

    Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result shows that Hawking radiation from the non-spherical symmetric black holes also can be derived from the viewpoint of anomaly.

  10. Stephen Hawking%史蒂芬·霍金

    Institute of Scientific and Technical Information of China (English)

    李同良

    2006-01-01

    @@ Professor Stephen William Hawking was born on 8 January 1942 in Oxford, England, which is exactly 300 years after the death of Galileo1. From a very early age Hawking showed the qualities2 of a scientist. He was always inquisitive3 and liked to build models to see how things worked.

  11. Delayed response in the Hawk Dove game

    Science.gov (United States)

    Burridge, James; Gao, Yu; Mao, Yong

    2017-01-01

    We consider a group of agents playing the Hawk-Dove game. These agents have a finite memory of past interactions which they use to optimize their play. By both analytical and numerical approaches, we show that an instability occurs at a critical memory length, and we provide its characterization. We show also that when the game is stable, having a long memory is beneficial but that instability, which may be produced by excessively long memory, hands the advantage to those with shorter memories.

  12. Study on the collision-mechanical properties of tomatoes gripped by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-15

    Dec 15, 2009 ... The data of collision-mechanical property of tomatoes gripped by robot fingers are important for the gripping control of .... Figure 2a shows the process of robot fingers gripping tomato. ..... Drop test simulation of a sample.

  13. Improved Friction Joint With Self-Locking Grips

    DEFF Research Database (Denmark)

    Costache, Andrei; Glejbøl, Kristian; Sivebæk, Ion Marius

    2016-01-01

    Flexible risers are used in the oil industry to transport liquids and gas from the seafloorto extraction and production equipment at the sea surface. Ongoing research aims at using composite materials instead of steel, in order to reduce weight and increase stiffness. Ensuring an optimal load...... transfer between the composite and metal components is very important. This paper presents an improved method for anchoring a flat fiber reinforced tendon using a double grip system with self-locking grips. The novelty is the combination of new experimental results and finite element (FE) analysis...... to develop asuperior dry friction grip. Experimental results are carried using a dedicated test setup, through which the test parameters can be accurately controlled. The efficiency of the grip system during pullout is superior to results obtained with flat grips. Numerical results offer an in...

  14. The Hawking Corpuscular Cascading from the Backreacted Black Hole

    CERN Document Server

    Övgün, A

    2016-01-01

    Exciting peculiarities of the Planck scale physics have an immediate effect on the Hawking radiation (HR) from black hole (BH). In this paper, by using the tunneling formalism we determine the Hawking temperature for the vector particles from a backreacted black hole (BBH), which is constructed from the conformal scalar field surrounded by BTZ black hole. Then we extend our calculations for scalar particles with the effect of generalized uncertainty principle (GUP) to understand the effect of quantum gravity. Then we calculate an evaporation time of the BBH, total number of Hawking particles and its quantum corrections. We observe that the remnants in the black hole evaporation are occured and they affect the Hawking temperature of the BBH and also the total number of Hawking particles.

  15. Hawking radiation, the Stefan–Boltzmann law, and unitarization

    Energy Technology Data Exchange (ETDEWEB)

    Giddings, Steven B., E-mail: giddings@physics.ucsb.edu

    2016-03-10

    Where does Hawking radiation originate? A common picture is that it arises from excitations very near or at the horizon, and this viewpoint has supported the “firewall” argument and arguments for a key role for the UV-dependent entanglement entropy in describing the quantum mechanics of black holes. However, closer investigation of both the total emission rate and the stress tensor of Hawking radiation supports the statement that its source is a near-horizon quantum region, or “atmosphere,” whose radial extent is set by the horizon radius scale. This is potentially important, since Hawking radiation needs to be modified to restore unitarity, and a natural assumption is that the scales relevant to such modifications are comparable to those governing the Hawking radiation. Moreover, related discussion suggests a resolution to questions regarding extra energy flux in “nonviolent” scenarios, that does not spoil black hole thermodynamics as governed by the Bekenstein–Hawking entropy.

  16. Hawking radiation inside a Schwarzschild black hole

    CERN Document Server

    Hamilton, Andrew J S

    2016-01-01

    The boundary of any observer's spacetime is the boundary that divides what the observer can see from what they cannot see. The boundary of an observer's spacetime in the presence of a black hole is not the true (future event) horizon of the black hole, but rather the illusory horizon, the dimming, redshifting surface of the star that collapsed to the black hole long ago. The illusory horizon is the source of Hawking radiation seen by observers both outside and inside the true horizon. The perceived acceleration (gravity) on the illusory horizon sets the characteristic frequency scale of Hawking radiation, even if that acceleration varies dynamically, as it must do from the perspective of an infalling observer. The acceleration seen by a non-rotating free-faller both on the illusory horizon below and in the sky above is calculated for a Schwarzschild black hole. Remarkably, as an infaller approaches the singularity, the acceleration becomes isotropic, and diverging as a power law. The isotropic, power-law char...

  17. Plumage polymorphism and fitness in Swainson's hawks.

    Science.gov (United States)

    Briggs, C W; Collopy, M W; Woodbridge, B

    2011-10-01

    We examine the maintenance of a plumage polymorphism, variation in plumages among the same age and sex class within a population, in a population of Swainson's Hawks. We take advantage of 32 years of data to examine two prevalent hypotheses used to explain the persistence of morphs: apostatic selection and heterozygous advantage. We investigate differences in fitness among three morph classes of a melanistic trait in Swainson's Hawks: light (7% of the local breeding population), intermediate (57%) and dark (36%). Specifically, we examined morph differences in adult apparent survival, breeding success, annual number of fledglings produced, probability of offspring recruitment into the breeding population and lifetime reproductive success (LRS). If apostatic selection were a factor in maintaining morphs, we would expect that individuals with the least frequent morph would perform best in one or more of these fitness categories. Alternatively, if heterozygous advantage played a role in the maintenance of this polymorphism, we would expect heterozygotes (i.e. intermediate morphs) to have one or more increased rates in these categories. We found no difference in adult apparent survival between morph classes. Similarly, there were no differences in breeding success, nest productivity, LRS or probability of recruitment of offspring between parental morph. We conclude that neither apostatic selection nor heterozygous advantage appear to play a role in maintaining morphs in this population.

  18. A red-tailed hawk at KSC

    Science.gov (United States)

    2000-01-01

    At KSC, a red-tailed hawk waits on top of a utility pole for the slightest movement in the grass below. It feeds mostly on small rodents. Ranging in height from 18 inches to 25 inches, the species has a stocky build with a whitish breast and rust-colored tail. It has a high-pitched descending scream with a hoarse quality. The hawk inhabits mainly deciduous forest and adjacent open country from Alaska and Nova Scotia south to Panama. KSC shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  19. Hawking radiation as perceived by different observers

    CERN Document Server

    Barbado, Luis C; Garay, Luis J

    2011-01-01

    We use a method recently introduced in Barcel\\'o et al, arXiv:1011.5593 [gr-qc] to analyse Hawking radiation in a Schwarzschild black hole as perceived by different observers in the system. The method is based on the introduction of an "effective temperature" function that varies with time. First we introduce a non-stationary vacuum state for a quantum scalar field, which interpolates between the Boulware vacuum state at early times and the Unruh vacuum state at late times. In this way we mimic the process of switching on Hawking radiation in realistic collapse scenarios. Then, we analyse this vacuum state from the perspective of static observers at different radial positions, observers undergoing a free-fall trajectory from infinity, and observers standing at rest at a radial distance and then released to fall freely towards the horizon. The physical image that emerges from these analyses is rather rich and compelling. Among many other results, we find that generic freely-falling observes do not perceive vac...

  20. Time Dependence of Hawking Radiation Entropy

    CERN Document Server

    Page, Don N

    2013-01-01

    If a black hole starts in a pure quantum state and evaporates completely by a unitary process, the von Neumann entropy of the Hawking radiation initially increases and then decreases back to zero when the black hole has disappeared. Here numerical results are given for an approximation to the time dependence of the radiation entropy under an assumption of fast scrambling, for large nonrotating black holes that emit essentially only photons and gravitons. The maximum of the von Neumann entropy then occurs after about 53.81% of the evaporation time, when the black hole has lost about 40.25% of its original Bekenstein-Hawking (BH) entropy (an upper bound for its von Neumann entropy) and then has a BH entropy that equals the entropy in the radiation, which is about 59.75% of the original BH entropy 4 pi M_0^2, or about 7.509 M_0^2 \\approx 6.268\\times 10^{76}(M_0/M_\\odot)^2, using my 1976 calculations that the photon and graviton emission process into empty space gives about 1.4847 times the BH entropy loss of the...

  1. On the paradox of Hawking radiation in a maximally extended Schwarzschild solution

    CERN Document Server

    Ellis, George F R

    2013-01-01

    This paper considers the effect of Hawking radiation on an eternal black hole - that is. a maximally extended Schwarzschild solution. Symmetry considerations that hold independent of the details of the emission mechanism show there is an inconsistency in the claim that such a blackhole evaporates away in a finite time. In essence: because the external domain is static, there is an infinite time available for the process to take place, so whenever the evaporation process is claimed to come to completion, it should have happened earlier. The problem is identified to lie in the claim that the locus of emission of Hawking radiation lies just outside the globally defined event horizon. Rather, the emission domain must be mainly located inside the event horizon, so most of the Hawking radiation ends up at this singularity rather than at infinity and the black hole never evaporates away. This result supports a previous claim [arXiv:1310.4771] that astrophysical black holes do not evaporate.

  2. Proximal arm kinematics affect grip force-load force coordination.

    Science.gov (United States)

    Vermillion, Billy C; Lum, Peter S; Lee, Sang Wook

    2015-10-01

    During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct proximal kinematics (elbow/shoulder), but resulted in similar end-point (hand) trajectories. While temporal coordination of grip and load forces remained similar across the tasks, proximal kinematics significantly affected the grip force-to-load force ratio (P = 0.042), intrinsic finger muscle activation (P = 0.045), and flexor-extensor ratio (P muscles and the elbow joint cannot fully explain the observed changes, as task-related changes in intrinsic hand muscle activation were greater than in extrinsic hand muscles. Rather, between-task variation in grip force (highest during task 3) appears to contrast to that in shoulder joint velocity/acceleration (lowest during task 3). These results suggest that complex neural coupling between the distal and proximal upper extremity musculature may affect grip force control during movements, also indicated by task-related changes in intermuscular coherence of muscle pairs, including intrinsic finger muscles. Furthermore, examination of the fingertip force showed that the human motor system may attempt to reduce variability in task-relevant motor output (grip force-to-load force ratio), while allowing larger fluctuations in output less relevant to task goal (shear force-to-grip force ratio).

  3. Experimental vacuolar myelinopathy in red-tailed hawks.

    Science.gov (United States)

    Fischer, John R; Lewis-Weis, Lynn A; Tate, Cynthia M

    2003-04-01

    Avian vacuolar myelinopathy (AVM) was recognized in 1994 as a cause of wild bird mortality when 29 bald eagles (Haliaeetus leucocephalus) succumbed to the disease at DeGray Lake, Arkansas (USA). The cause of AVM and its source remain undetermined despite extensive diagnostic and research investigations. Two years later, when AVM killed 26 eagles in the same area in Arkansas, it became apparent that American coots (Fulica americana) had identical neurologic signs and lesions, and it was hypothesized that eagles acquired AVM via ingestion of affected coots. In order to test this hypothesis, we fed coot tissues (brain, liver, kidney, muscle, fat, and intestinal tract) to rehabilitated, non-releasable red-tailed hawks (Buteo jamaicensis). Five hawks received tissues from coots with AVM lesions, and one hawk received tissues from coots without brain lesions that had been collected at a site where AVM never has been documented. All hawks received 12-70 g/day (mean = 38 g) of coot tissues for 28 days. All six hawks remained clinically normal during the study. The birds were euthanatized on day 29 and microscopic lesions of AVM were found in all hawks that received tissues from affected coots, but not in the hawk that received tissues from unaffected coots. This marks the first time that AVM has been produced in birds under laboratory conditions and proves that birds of prey can acquire AVM via ingestion of tissues from affected coots.

  4. Hawking radiation from magnetized Kerr-Newman black hole

    Science.gov (United States)

    Rizwan, Muhammad; Saifullah, K.

    2016-12-01

    Hawking radiation of charged scalar and Dirac particles from the event horizon of magnetized Kerr-Newman black holes is studied using the Hamilton-Jacobi method and WKB approximation. This is done by calculating tunneling probabilities of these particles from the horizons of magnetized black holes. This method yields the Hawking temperature of magnetized Kerr-Newman black holes as well. It is interesting to note that while the tunneling probabilities depend upon the background magnetic field, the Hawking temperature is not affected by magnetization.

  5. Landauer Transport Model for Hawking Radiation from a Black Hole

    CERN Document Server

    Nation, P D; Nori, Franco

    2010-01-01

    We investigate the Hawking radiation energy and entropy flow rates from a black hole viewed as a one-dimensional (1D) Landauer transport process. The conformal symmetry in the near-horizon region leads directly to radiation rates that are identical to those of a single 1D quantum channel connected to a thermal reservoir at the Hawking temperature. The particle statistics independence of the 1D energy and entropy currents is applied to a black hole radiating into vacuum as well as one near thermal equilibrium with its environment. The Hawking radiation entropy production ratio is also examined.

  6. JPL Genesis and Rapid Intensification Processes (GRIP) Portal

    Science.gov (United States)

    Knosp, Brian W.; Li, P. Peggy; Vu, Quoc A.; Turk, Francis J.; Shen, Tsae-Pyng J.; Hristova-Veleva, Svetla M.; Licata, Stephen J.; Poulsen, William L.

    2012-01-01

    Satellite observations can play a very important role in airborne field campaigns, since they provide a comprehensive description of the environment that is essential for the experiment design, flight planning, and post-experiment scientific data analysis. In the past, it has been difficult to fully utilize data from multiple NASA satellites due to the large data volume, the complexity of accessing NASA s data in near-real-time (NRT), as well as the lack of software tools to interact with multi-sensor information. The JPL GRIP Portal is a Web portal that serves a comprehensive set of NRT observation data sets from NASA and NOAA satellites describing the atmospheric and oceanic environments related to the genesis and intensification of the tropical storms in the North Atlantic Ocean. Together with the model forecast data from four major global atmospheric models, this portal provides a useful tool for the scientists and forecasters in planning and monitoring the NASA GRIP field campaign during the 2010 Atlantic Ocean hurricane season. This portal uses the Google Earth plug-in to visualize various types of data sets, such as 2D maps, wind vectors, streamlines, 3D data sets presented at series of vertical cross-sections or pointwise vertical profiles, and hurricane best tracks and forecast tracks. Additionally, it allows users to overlap multiple data sets, change the opacity of each image layer, generate animations on the fly with selected data sets, and compare the observation data with the model forecast using two independent calendars. The portal also provides the capability to identify the geographic location of any point of interest. In addition to supporting the airborne mission planning, the NRT data and portal will serve as a very rich source of information during the post-field campaign analysis stage of the airborne experiment. By including a diverse set of satellite observations and model forecasts, it provides a good spatial and temporal context for the

  7. 英诗Hawk Roosting的主位结构及特点%The thematic structure features of Hawk Roosting

    Institute of Scientific and Technical Information of China (English)

    许耘

    2008-01-01

    一个句子或小句表达信息的起点是主位,围绕主位加以叙述发展的部分是叙位.主位传递的是已知信息,叙位传递的是新信息.在hawk roosting中,出现频率最高的主位是I,全诗虽没有出现一个点题的Hawk(鹰)字眼,但这个第一人称代词实际上指的就是Hawk.

  8. Nesting habitat relationships of sympatric Crested Caracaras, Red-tailed Hawks, and White-tailed Hawks in South Texas

    Science.gov (United States)

    Actkinson, M.A.; Kuvlesky, W.P.; Boal, C.W.; Brennan, L.A.; Hernandez, F.

    2007-01-01

    We quantified nesting-site habitats for sympatric White-tailed Hawks (Buteo albicaudatus) (n = 40), Red-tailed Hawks (B. jamaicensis) (n = 39), and Crested Caracaras (Caracara cheriway) (n = 24) in the Coastal Sand Plain of south Texas. White-tailed Hawks and Crested Caracara nest sites occurred in savannas, whereas Red-tailed Hawk nest sites occurred in woodlands on the edge of savannas. White-tailed Hawk nest sites were in shrubs and trees that were shorter (3.5 ?? 1.0 m) and had smaller canopy diameters (5.5 ?? 2.1 m) than those of Red-tailed Hawks (10.1 ?? 2.0 m, 13.7 ?? 5.8 m) and Crested Caracaras (5.6 ?? 1.7 m, 8.5 ?? 3.5 m). Red-tailed Hawk nest sites had higher woody densities (15.7 ?? 9.6 plants) and more woody cover (84 ?? 19%) than those of White-tailed Hawks (5.6 ?? 5.8 plants, 20 ?? 21%) and Crested Caracaras (9.9 ?? 6.7 plants, 55 ?? 34%). Crested Caracara nest sites were in dense, multi-branched shrubs composed of more living material (97 ?? 3%) than those of White-tailed (88 ?? 18%) and Red-tailed hawks (88 ?? 18%). Nest sites of White-tailed Hawks, Red-tailed Hawks, and Crested Caracaras were similar to random samples from the surrounding habitat indicating that preferred nesting habitat was available for each of these species at least within 60 m of active nest sites. Nest tree height, along with woody plant and native grass cover best discriminated nest sites among the three raptor species. There was no overlap at Red-tailed and White-tailed hawk nest sites in vegetation structure, while Crested Caracara nests were in habitat intermediate between the two other species. Partitioning of nesting habitat may be how these raptor species co-exist at the broader landscape scale of our study area in the Coastal Sand Plain of Texas.

  9. The Hawking temperature in the context of dark energy

    Science.gov (United States)

    Gangopadhyay, Debashis; Manna, Goutam

    2012-11-01

    An emergent-gravity metric incorporating k-essence scalar fields ϕ having a Born-Infeld-type Lagrangian is mapped into a metric whose structure is similar to that of a blackhole of large mass M that has swallowed a global monopole. However, here the field is not that of a monopole but rather that of a k-essence scalar field. If ϕemergent are the solutions of the emergent-gravity equations of motion under cosmological boundary conditions at ∞, then for r\\rightarrow \\infty the rescaled field \\frac {\\phi _{emergent}}{2GM-1} has exact correspondence with ϕ with ϕ(r,t) = ϕ1(r) + ϕ2(t). The Hawking temperature of this metric is T_{ emergent}= \\frac {\\hbar c^{3}}{8\\pi GM k_{B}}(1-K)^{2}\\equiv \\frac {\\hbar }{8\\pi GM k_{B}}(1-K)^{2} , taking the speed of light c = 1. Here K=\\dot \\phi _{2}^{2} is the kinetic energy of the k-essence field ϕ and K is always less than unity, kB is the Boltzmann constant. This is phenomenologically interesting in the context of Belgiorno et al.'s gravitational analogue experiment.

  10. The Hawking temperature in the context of dark energy

    CERN Document Server

    Gangopadhyay, Debashis

    2012-01-01

    An emergent gravity metric incorporating $k-$essence scalar fields $\\phi$ having a Born-Infeld type lagrangian is mapped into a metric whose structure is similar to that of a blackhole of large mass $M$ that has swallowed a global monopole. However, here the field is not that of a monopole but rather that of a $k-$essence scalar field. If $\\phi_{emergent}$ be solutions of the emergent gravity equations of motion under cosmological boundary conditions at $\\infty$, then for $r\\rightarrow\\infty$ the rescaled field $\\frac {\\phi_{emergent}}{2GM-1}$ has exact correspondence with $\\phi$ with $\\phi(r,t)=\\phi_{1}(r)+\\phi_{2}(t)$. The Hawking temperature of this metric is $T_{\\mathrm emergent}= \\frac{\\hbar c^{3}}{8\\pi GM k_{\\mathrm B}}(1-K)^{2}\\equiv \\frac{\\hbar}{8\\pi GM k_{\\mathrm B}}(1-K)^{2}$, taking the speed of light $c=1$. Here $K=\\dot\\phi_{2}^{2}$ is the kinetic energy of the $k-$essence field $\\phi$ and $K$ is always less than unity, $k_{\\mathrm B}$ is the Boltzmann constant. This is phenomenologically interest...

  11. The theory of Hawking radiation in laboratory analogues

    CERN Document Server

    Robertson, Scott

    2015-01-01

    Hawking radiation, despite being known to theoretical physics for nearly forty years, remains elusive and undetected. It also suffers, in its original context of gravitational black holes, from practical and conceptual difficulties. Of particular note is the trans-Planckian problem, which is concerned with the apparent origin of the radiation in absurdly high frequencies. In order to gain better theoretical understanding and, it is hoped, experimental verification of Hawking radiation, much study is being devoted to laboratory systems which use moving media to model the spacetime geometry of black holes, and which, by analogy, are also thought to emit Hawking radiation. These analogue systems typically exhibit dispersion, which regularizes the wave behaviour at the horizon at the cost of a more complicated theoretical framework. This tutorial serves as an introduction to Hawking radiation and its analogues, developing the moving medium analogy for black holes and demonstrating how dispersion can be incorporat...

  12. Rotating embedded black holes: Entropy and Hawking's radiation

    OpenAIRE

    2004-01-01

    In this paper we derive a class of rotating embedded black holes. Then we study Hawking's radiation effects on these embedded black holes. The surface gravity, entropy and angular velocity are given for each of these black holes.

  13. Influence of poisoned prey on foraging behavior of ferruginous hawks

    Science.gov (United States)

    Vyas, Nimish B.; Kuncir, Frank; Clinton, Criss C.

    2017-01-01

    We recorded 19 visits by ferruginous hawks (Buteo regalis) over 6 d at two black–tailed prairie dog (Cynomys ludovicianus) subcolonies poisoned with the rodenticide Rozol® Prairie Dog Bait (0.005% chlorophacinone active ingredient) and at an adjacent untreated subcolony. Before Rozol® application ferruginous hawks foraged in the untreated and treated subcolonies but after Rozol® application predation by ferruginous hawks was only observed in the treated subcolonies. We suggest that ferruginous hawks' preference for hunting in the treated subcolonies after Rozol® application was influenced by the availability of easy-to-capture prey, presumably due to Rozol® poisoning. The energetically beneficial behavior of favoring substandard prey may increase raptor encounters with rodenticide exposed animals if prey vulnerability has resulted from poisoning.

  14. GUP assisted Hawking radiation of rotating acoustic black holes

    Science.gov (United States)

    Sakalli, I.; Övgün, A.; Jusufi, K.

    2016-10-01

    Recent studies (Steinhauer in Nat. Phys. 10:864, 2014, Phys. Rev. D 92:024043, 2015) provide compelling evidences that Hawking radiation could be experimentally proven by using an analogue black hole. In this paper, taking this situation into account we study the quantum gravitational effects on the Hawking radiation of rotating acoustic black holes. For this purpose, we consider the generalized uncertainty principle (GUP) in the phenomenon of quantum tunneling. We firstly take the modified commutation relations into account to compute the GUP modified Hawking temperature when the massive scalar particles tunnel from this black hole. Then, we find a remarkably instructive expression for the GUP entropy to derive the quantum gravity corrected Hawking temperature of the rotating acoustic black hole.

  15. Stephen Hawking ja tema kuulsad kihlveod / Andi Hektor

    Index Scriptorium Estoniae

    Hektor, Andi, 1975-

    2010-01-01

    Ratastooli aheldatud füüsikaikoon Hawking armastab sõlmida kihlvedusid. Viimane kihlvedu, mis puudutab gravitatsioonilainete ja inflatsiooni olemasolu, on taas päevakorda tõusnud, sest eelmisel aastal alustas mõõtmisi Plancki satelliit

  16. GUP Assisted Hawking Radiation of Rotating Acoustic Black Holes

    CERN Document Server

    Sakalli, I; Jusufi, K

    2016-01-01

    Recent studies [J. Steinhauer, Nature Phys., $\\textbf{10}$, 864 (2014); Phys. Rev. D $\\textbf{92}$, 024043 (2015)] provide compelling evidences that Hawking radiation could be experimentally proven by using an analogue black hole. In this paper, taking this situation into account we study the quantum gravitational effects on the Hawking radiation of rotating acoustic black holes. For this purpose, we consider the generalized uncertainty principle (GUP) in the phenomenon of quantum tunneling. We firstly take the modified commutation relations into account to compute the GUP modified Hawking temperature when the massive scalar particles tunnel from this black hole. Then, we find a remarkably instructive expression for the GUP entropy to derive the quantum gravity corrected Hawking temperature of the rotating acoustic black hole.

  17. Hawking Temperature of an Arbitrarily Accelerating Black Hole

    Indian Academy of Sciences (India)

    Wei-Zhen Pan; Wei Liu

    2014-09-01

    Hawking temperature of an arbitrarily accelerating black hole with electric and magnetic charges are obtained based on the Klein–Gordon equation with a correct-dimension new tortoise coordinate transformation.

  18. End Point of Hawking Evaporation -- Case of Integrable Model

    CERN Document Server

    Hotta, M

    1994-01-01

    Quantum back reaction due to $N$ massless fields may be worked out to a considerable detail in a variant of integrable dilaton gravity model in two dimensions. It is shown that there exists a critical mass of collapsing object of order $\\hbar N \\times$ (cosmological constant)$^{1/2}$, above which the end point of Hawking evaporation is two disconnected remnants of infinite extent, each separated by a mouth from the outside region. Deep inside the mouth there is a universal flux of radiation in all directions, in a form different from Hawking radiation. Below the critical mass no remnant is left behind, implying complete Hawking evaporation or even showing no sign of Hawking radiation. Existence of infinitely many static states of quantum nature is also demonstrated in this model.

  19. Effect of syllable articulation on precision and power grip performance.

    Directory of Open Access Journals (Sweden)

    Lari Vainio

    Full Text Available The present study was motivated by a theory, which proposes that speech includes articulatory gestures that are connected to particular hand actions. We hypothesized that certain articulatory gestures would be more associated with the precision grip than with the power grip, and vice versa. In the study, the participants pronounced a syllable and performed simultaneously a precision or power grip that was theorized to be either congruent or incongruent with the syllable. Relatively fast precision grip responses were associated with articulatory gestures in which the tip of the tongue contacted the alveolar ridge ([te] or the aperture of the vocal tract remained small ([hi], as well as gestures that required lip protrusion ([pu]. In contrast, relatively fast power grip responses were associated with gestures that were produced by moving the back of the tongue against the velum ([ke] or in which the aperture of the vocal tract remained large ([hα]. In addition to demonstrating that certain articulatory gestures are systematically connected to different grip types, the study may shed some light on discussion concerning sound symbolism and evolution of speech.

  20. Sense and avoid technology for Global Hawk and Predator UAVs

    Science.gov (United States)

    McCalmont, John F.; Utt, James; Deschenes, Michael; Taylor, Michael J.

    2005-05-01

    The Sensors Directorate at the Air Force Research Laboratory (AFRL) along with Defense Research Associates, Inc. (DRA) conducted a flight demonstration of technology that could potentially satisfy the Federal Aviation Administration's (FAA) requirement for Unmanned Aerial Vehicles (UAVs) to sense and avoid local air traffic sufficient to provide an "...equivalent level of safety, comparable to see-and-avoid requirements for manned aircraft". This FAA requirement must be satisfied for autonomous UAV operation within the national airspace. The real-time on-board system passively detects approaching aircraft, both cooperative and non-cooperative, using imaging sensors operating in the visible/near infrared band and a passive moving target indicator algorithm. Detection range requirements for RQ-4 and MQ-9 UAVs were determined based on analysis of flight geometries, avoidance maneuver timelines, system latencies and human pilot performance. Flight data and UAV operating parameters were provided by the system program offices, prime contractors, and flight-test personnel. Flight demonstrations were conducted using a surrogate UAV (Aero Commander) and an intruder aircraft (Beech Bonanza). The system demonstrated target detection ranges out to 3 nautical miles in nose-to-nose scenarios and marginal visual meteorological conditions. (VMC) This paper will describe the sense and avoid requirements definition process and the system concept (sensors, algorithms, processor, and flight rest results) that has demonstrated the potential to satisfy the FAA sense and avoid requirements.

  1. Questioning the recent observation of quantum Hawking radiation

    CERN Document Server

    Leonhardt, Ulf

    2016-01-01

    A recent paper [J. Steinhauer, doi:10.1038/nphys3863, arXiv:1510.00621] has claimed the observation of quantum Hawking radiation and its entanglement in an analogue black hole. However, while the author has achieved an extraordinary experimental feat, the claims of the paper do not stand up to scrutiny: they are not sufficiently supported by evidence, are obtained with biased methods and violate hard theoretical bounds, which raises severe doubts on the observation of Hawking radiation.

  2. Non-thermal Hawking radiation from the Kerr black hole

    Institute of Scientific and Technical Information of China (English)

    HAN Yi-Wen; HAO Jia-Bo

    2009-01-01

    We present a short and direct derivation of Hawking radiation by using the Damour-Ruffini method, as taking into account the self-gravitational interaction from the Kerr black hole. It is found that the radiation is not exactly thermal, and because the derivation obeys conservation laws, the non-thermal Hawking radiation can carry information from the black hole. So it can be used to explain the black hole information paradox, and the process satisfies unitary.

  3. Hawking radiation of a uniformly accelerating black hole

    Institute of Scientific and Technical Information of China (English)

    Ren Jun; Cao Jiang-Ling; Zhao Zheng

    2006-01-01

    In this paper, we study the Hawking radiation via tunnelling from a uniformly accelerating black hole. Although the Bekenstein-Hawking entropy is proportional also to the area of the event horizon, the radius of it, rH, is a function of θ, which leads to the difficulties in the calculation of the emission rate. In order to overcome the mathematical difficulties, we propose a new technique to calculate the emission rate and the result obtained is reasonable.

  4. Street Hawking: Oppressing the Girl Child or Family Economic Supplement?

    Science.gov (United States)

    Umar, Fatima M.

    2009-01-01

    Street hawking in its simplest form is the selling of things along the roads and from one place to the other. In Nigeria this is done almost all the time by young children both males and females. The girl hawkers come to the cities in groups and then go in different directions of the city to hawk their goods. They remain in the city from the early…

  5. Hawking receives top US award at White House

    Science.gov (United States)

    Banks, Michael

    2009-09-01

    The Cambridge physicist Stephen Hawking has been awarded the highest US civilian honour - the presidential medal of freedom. At a ceremony at the White House last month, Hawking, together with 15 other recipients, received the 2009 award from President Barack Obama. The medal is given to individuals who make a contribution "to the security or national interests of the US, world peace, cultural or other significant public or private endeavours".

  6. Corrected Hawking Temperature in Snyder's Quantized Space-time

    Science.gov (United States)

    Ma, Meng-Sen; Liu, Fang; Zhao, Ren

    2015-06-01

    In the quantized space-time of Snyder, generalized uncertainty relation and commutativity are both included. In this paper we analyze the possible form for the corrected Hawking temperature and derive it from the both effects. It is shown that the corrected Hawking temperature has a form similar to the one of noncommutative geometry inspired Schwarzschild black hole, however with an requirement for the noncommutative parameter 𝜃 and the minimal length a.

  7. Anomaly Analysis of Hawking Radiation from Acoustic Black Hole

    CERN Document Server

    Kim, Wontae

    2007-01-01

    The Hawking radiation from the three dimensional rotating acoustic black hole is considered from the viewpoint of anomaly cancellation method initiated by Robinson and Wilczek. Quantum field near the horizon is effectively described by two dimensional charged field with a charge identified as the angular momentum m. The fluxes of charge and energy are obtained from the anomaly cancellation condition and regularity at the horizon, and are shown to match with those of the two dimensional black body radiation at the Hawking temperature.

  8. Equivalence of the Hawking temperature in conformal frames

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Glauber Tadaiesky [Universidade Federal Rural da Amazonia-Brazil, ICIBE-LASIC, Belem/PA (Brazil); Rodrigues, Manuel E. [Universidade Federal do Espirito Santo, Centro de Ciencias Exatas, Departamento de Fisica, Vitoria/ES (Brazil)

    2012-02-15

    The conformal invariance of the Hawking temperature, conjectured for the asymptotically flat and stationary black holes by Jacobson and Kang, is semiclassically evaluated for a simple particular case of symmetrical spherically and non-asymptotically flat black hole. By using the Bogoliubov coefficients, the metric euclideanization, the reflection coefficient and the gravitational anomaly, as methods of calculating the Hawking temperature, we find that it is invariant under a specific conformal transformation of the metric. We briefly discuss the results for each method. (orig.)

  9. Hélène Mialet, Hawking Incorporated. Stephen Hawking and the Anthropology of the Knowing subject

    OpenAIRE

    Popescu, Cristina

    2013-01-01

    Situé dans la tradition de recherche développée autour de la théorie de l’acteur-réseau (actor-network theory), le livre de Hélène Mialet choisit d’explorer la figure particulière du physicien anglais Stephen Hawking. À travers sept chapitres complémentaires, le lecteur découvre à la fois « Hawking l’individu » et « Hawking le génie en physique ». C’est une distinction qui ne paraît pas toute de suite évidente au non-initié, mais, nous allons le comprendre rapidement, le Hawking des médias, n...

  10. Grip op werkstress. Mindfulness ontstresst maatschappelijk werkers

    Directory of Open Access Journals (Sweden)

    Jen van Horen

    2014-03-01

    Full Text Available Taking control over work related stress. Mindfulness destresses social workersStress is a major social problem. Due to the increasing workload and the content of the work, social workers are at risk to develop stress (symptoms. The physical and psychological consequences of prolonged stress are serious. By living healthy, optimize working conditions and applying mindfulness, stress can be reduced. Mindfulness is an effective and useful way to reduce stress. It increases the resistance of workers against stress, improves brainfunctions and therefore has a positive effect on the performance. These effects are great, but they are still weakly methodologically substantiated. A pilot project within the youthcare though, was enthusiastically received and proves to be effective against stress symptoms. The exercises that are part of this pilot fit well with the needs of employees. For organizations mindfulnesstrainings are a time-and cost-effective way of structural stress prevention.Grip op werkstress. Mindfulness ontstresst maatschappelijk werkersStress is een omvangrijk maatschappelijk probleem. Door de toenemende werkdruk en de inhoud van het werk zijn maatschappelijk werkers een risicogroep om stress en stressklachten te ontwikkelen. De fysieke en psychische gevolgen die langdurige stress met zich meebrengt zijn ernstig. Door gezond te leven, de arbeidsomstandigheden te optimaliseren en mindfulness toe te passen kan stress terug worden gedrongen. Mindfulness is een effectieve en bruikbare manier om stress te verminderen. Het vergroot de weerbaarheid van werknemers tegen stress, het verbetert de hersenwerking en heeft daardoor een positief effect op het functioneren. Grote effecten dus, maar wel nog methodologisch zwak onderbouwd. Een pilot binnen de jeugdzorg op het gebied van mindfulness is enthousiast ontvangen en blijkt effectief tegen stressklachten. De oefeningen die onderdeel uitmaken van deze pilot sluiten goed aan bij de behoeften van

  11. Association of grip strength with cardiovascular risk markers.

    Science.gov (United States)

    Gubelmann, Cédric; Vollenweider, Peter; Marques-Vidal, Pedro

    2017-03-01

    Background Mechanisms underlying the association between grip strength and cardiovascular mortality are poorly understood. We aimed to assess the association of grip strength with a panel of cardiovascular risk markers. Design The study was based on a cross-sectional analysis of 3468 adults aged 50-75 years (1891 women) from a population-based sample in Lausanne, Switzerland. Methods Grip strength was measured using a hydraulic hand dynamometer. Cardiovascular risk markers included anthropometry, blood pressure, lipids, glucose, adiposity, inflammatory and other metabolic markers. Results In both genders, grip strength was negatively associated with fat mass (Pearson correlation coefficient: women: -0.170, men: -0.198), systolic blood pressure (women: -0.096, men: -0.074), fasting glucose (women: -0.048, men: -0.071), log-transformed leptin (women: -0.074, men: -0.065), log-transformed high-sensitivity C-reactive protein (women: -0.101, men: -0.079) and log-transformed homocysteine (women: -0.109, men: -0.060). In men, grip strength was also positively associated with diastolic blood pressure (0.068), total (0.106) and low density lipoprotein-cholesterol (0.082), and negatively associated with interleukin-6 (-0.071); in women, grip strength was negatively associated with triglycerides (-0.064) and uric acid (-0.059). After multivariate adjustment, grip strength was negatively associated with waist circumference (change per 5 kg increase in grip strength: -0.82 cm in women and -0.77 cm in men), fat mass (-0.56% in women; -0.27% in men) and high-sensitivity C-reactive protein (-6.8% in women; -3.2% in men) in both genders, and with body mass index (0.22 kg/m(2)) and leptin (-2.7%) in men. Conclusion Grip strength shows only moderate associations with cardiovascular risk markers. The effect of muscle strength as measured by grip strength on cardiovascular disease does not seem to be mediated by cardiovascular risk markers.

  12. Hawking Incorporated Stephen Hawking and the Anthropology of the Knowing Subject

    CERN Document Server

    Mialet, Hélène

    2012-01-01

    These days, the idea of the cyborg is less the stuff of science fiction and more a reality, as we are all, in one way or another, constantly connected, extended, wired, and dispersed in and through technology. One wonders where the individual, the person, the human, and the body are-or, alternatively, where they stop. These are the kinds of questions Hélène Mialet explores in this fascinating volume, as she focuses on a man who is permanently attached to assemblages of machines, devices, and collectivities of people: Stephen Hawking. Drawing on an extensive and in-depth series of interviews wi

  13. Bekenstein-Hawking Entropy and Strange Metals

    CERN Document Server

    Sachdev, Subir

    2015-01-01

    We examine models of fermions with infinite-range interactions which realize non-Fermi liquids with a continuously variable U(1) charge density $\\mathcal{Q}$, and a non-zero entropy density $\\mathcal{S}$ at vanishing temperature. Real time correlators of operators carrying U(1) charge $q$ at a low temperature $T$ are characterized by a $\\mathcal{Q}$-dependent frequency $\\omega_{\\mathcal{S}} = (q \\, T/\\hbar) (\\partial \\mathcal{S}/\\partial{\\mathcal{Q}})$ which determines a spectral asymmetry. We show that the correlators match precisely with those of the AdS$_2$ horizons of extremal charged black holes. On the black hole side, the matching requires $\\mathcal{S}$ to be equal to the Bekenstein-Hawking entropy density, and employs the laws of black hole thermodynamics which relate $(\\partial{\\mathcal{S}}/\\partial{\\mathcal{Q}})/(2 \\pi)$ to the electric field strength in AdS$_2$. The fermion model entropy is computed using the microscopic degrees of freedom of a UV complete theory without supersymmetry.

  14. Why Hawking Radiation Cannot Be Decoded

    CERN Document Server

    Ong, Yen Chin; Chen, Pisin

    2014-01-01

    One of the great difficulties in the theory of black hole evaporation is that the most decisive phenomena tend to occur when the black hole is extremely hot: that is, when the physics is most poorly understood. Fortunately, a crucial step in the Harlow-Hayden approach to the firewall paradox, concerning the time available for decoding of Hawking radiation emanating from charged AdS black holes, can be made to work without relying on the unknown physics of black holes with extremely high temperatures; in fact, it relies on the properties of cold black holes. Here we clarify this surprising point. The approach is based on ideas borrowed from applications of the AdS/CFT correspondence to the quark-gluon plasma. Firewalls aside, our work presents a detailed analysis of the thermodynamics and evolution of evaporating charged AdS black holes with flat event horizons. We show that, in one way or another, these black holes are always eventually destroyed in a time which, while long by normal standards, is short relat...

  15. Individual finger contribution in submaximal voluntary contraction of gripping.

    Science.gov (United States)

    Kong, Yong-Ku; Lee, Kyung-Sun; Kim, Dae-Min; Jung, Myung-Chul

    2011-11-01

    The objective of this study was to evaluate individual finger force and contribution to a gripping force, the difference between actual and expected finger forces and subjective discomfort rating at 10 different submaximal voluntary contraction (%MVC) levels (10-100% in 10 increments). Seventy-two participants randomly exerted gripping force with a multi-finger force measurement system. The individual finger force, gripping force and discomfort increased as %MVC levels increased. The middle and ring fingers exerted more force and contributed to a gripping force more than the index and little fingers due to their larger mass fractions of the digit flexor muscles. It was apparent at MVC; however, the index finger increased its contribution and exerted even more force than expected at more than 50% MVC. Subjective discomfort supported the results of the objective measures. This could explain the conflicting findings between index and ring fingers in previous finger contribution studies. STATEMENT OF RELEVANCE: Hand tool design is of special interest in ergonomics due to its association with musculoskeletal disorders in the hand. This study reveals a different contribution pattern of the fingers in submaximal voluntary contraction of gripping exertion.

  16. Gripping tool for the ITER upper port plug RH extraction/insertion

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Elena V., E-mail: elena.rosa@ciemat.es; Ríos, Luis, E-mail: luis.rios@ciemat.es

    2014-10-15

    Highlights: •The gripping tool is based on only one gripping point centred at the plug bottom. •The gripping tool should allow the relative displacement in the gripping point to absorb the misalignment between plug and tractor. •The gripping tool needs to withstand around 100/30 kN during the plug extraction/insertion. •The gripping tool should rely on visual control and it has to avoid force feed-back. •The comparison between the features of several gripping tool concepts is assessed. -- Abstract: The conceptual design of several gripping tools and their mechanical interfaces is being carried out for the ITER ECH UPP within the WP10-GOTRH programme. EFDA finances the GOT RH (Goal Oriented Training Programme for Remote Handling). The purpose of this paper is to introduce new concepts of gripping tools for the plug extraction/insertion in the upper port of ITER. All these gripping tools are designed according to IO input data and geometrical constraints. The gripping tools have to be able to extract/insert the plug in the scenario of maximum misalignment between the plug and the tractor. The paper also defines the functional requirements the gripping tools need to comply with. The requirements and input data are verified and validated through 3D simulation with Catia mock-ups of the gripping tools. The strengths and weaknesses of each gripping tool model are compared.

  17. Hawking radiation, the Stefan–Boltzmann law, and unitarization

    Directory of Open Access Journals (Sweden)

    Steven B. Giddings

    2016-03-01

    Full Text Available Where does Hawking radiation originate? A common picture is that it arises from excitations very near or at the horizon, and this viewpoint has supported the “firewall” argument and arguments for a key role for the UV-dependent entanglement entropy in describing the quantum mechanics of black holes. However, closer investigation of both the total emission rate and the stress tensor of Hawking radiation supports the statement that its source is a near-horizon quantum region, or “atmosphere,” whose radial extent is set by the horizon radius scale. This is potentially important, since Hawking radiation needs to be modified to restore unitarity, and a natural assumption is that the scales relevant to such modifications are comparable to those governing the Hawking radiation. Moreover, related discussion suggests a resolution to questions regarding extra energy flux in “nonviolent” scenarios, that does not spoil black hole thermodynamics as governed by the Bekenstein–Hawking entropy.

  18. Globalization

    Institute of Scientific and Technical Information of China (English)

    范玮丽

    2008-01-01

    This paper mainly talks about the currently hot topic-globalization. Firstly, it brings out the general trend about globalization and how to better understand its implication. Secondly, it largely focuses on how to deal with it properly, especially for international marketers. Then, facing with the overwhelming trend, it is time for us to think about seriously what has globalization brought to us. Last but not least, it summarized the author's personal view about the future of globalization and how should we go.

  19. Globalization

    Directory of Open Access Journals (Sweden)

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  20. Recent trends in counts of migrant hawks from northeastern North America

    Science.gov (United States)

    Titus, K.; Fuller, M.R.

    1990-01-01

    Using simple regression, pooled-sites route-regression, and nonparametric rank-trend analyses, we evaluated trends in counts of hawks migrating past 6 eastern hawk lookouts from 1972 to 1987. The indexing variable was the total count for a season. Bald eagle (Haliaeetus leucocephalus), peregrine falcon (Falco peregrinus), merlin (F. columbarius), osprey (Pandion haliaetus), and Cooper's hawk (Accipiter cooperii) counts increased using route-regression and nonparametric methods (P 0.10). We found no consistent trends (P > 0.10) in counts of sharp-shinned hawks (A. striatus), northern goshawks (A. gentilis) red-shouldered hawks (Buteo lineatus), red-tailed hawks (B. jamaicensis), rough-legged hawsk (B. lagopus), and American kestrels (F. sparverius). Broad-winged hawk (B. platypterus) counts declined (P hawks are a useful and economical method for detecting long-term trends in species across regions, particularly for species that otherwise cannot be easily surveyed.

  1. G×E Interaction Influences Trajectories of Hand Grip Strength

    DEFF Research Database (Denmark)

    Petersen, Inge; Pedersen, Nancy L; Rantanen, Taina;

    2016-01-01

    and Environment across Multiple Studies consortium. Growth curve parameters were estimated for same-sex pairs, aged 34-99 (N = 10,681). Fisher's test for mixture distribution of within-monozygotic twin-pair differences (N = 1724) was performed on growth curve parameters. We observed significant gene......-environment interaction on grip strength trajectories. Finally, we compared the variability of within-pair differences of growth curve parameters by APOE haplotypes. Though not statistically significant, the results suggested that APOE ɛ2ɛ2/ɛ2ɛ3 haplotypes might buffer environmental influences on grip strength...

  2. Study of Silicon Photomultipliers for the GRIPS Calorimeter Module

    Directory of Open Access Journals (Sweden)

    Alexei Ulyanov

    2013-01-01

    Full Text Available GRIPS is a proposed gamma-ray (200 keV to 80 MeV astronomy mission, which incorporates a pair-creation and Compton scattering telescope, along with X-ray and infrared telescopes. It will carry out a sensitive all-sky scanning survey, investigating phenomena such as gamma-ray bursts, blazars and core collapse supernovae. The main telescope is composed of a Si strip detector surroundedby a calorimeter with a fast scintillator material. We present the initial results of a study which considers the potential use of silicon photomultipliers in conjunction with the scintillator in the GRIPS calorimeter module.

  3. Hawking radiation of five-dimensional charged black holes with scalar fields

    Science.gov (United States)

    Miao, Yan-Gang; Xu, Zhen-Ming

    2017-09-01

    We investigate the Hawking radiation cascade from the five-dimensional charged black hole with a scalar field coupled to higher-order Euler densities in a conformally invariant manner. We give the semi-analytic calculation of greybody factors for the Hawking radiation. Our analysis shows that the Hawking radiation cascade from this five-dimensional black hole is extremely sparse. The charge enhances the sparsity of the Hawking radiation, while the conformally coupled scalar field reduces this sparsity.

  4. Hawking Temperature of a Static Black Hole in Harmonic Coordinates

    Science.gov (United States)

    He, Guan-Sheng; Lin, Wei-Bin

    2015-12-01

    Hawking radiation is usually studied in standard coordinates. In this paper, we calculate the Hawking temperature of a Schwarzschild black hole in harmonic coordinates, as well as that of a Reissner-Nordström black hole. The action of a scalar field near the event horizon can be formulated exactly without omitting some high-order terms. We show dimensional reduction for Hawking temperature is also valid for harmonic coordinates, and verify further that the results are independent on concrete coordinates. With the help of Lorentz transformation, our work might also serve as a basis to investigate the thermal radiation from a moving black hole. Supported in part by the Ph.D. Programs Foundation of Ministry of Education of China under Grant No. 20110184110016, the National Basic Research Program of China (973 Program) Grant No. 2013CB328904, and the Fundamental Research Funds for the Central Universities under Grant No. 2682014ZT32

  5. Hawking radiation of non-asymptotically flat rotating black holes

    Science.gov (United States)

    Sakalli, Izzet; Aslan, Onur Atilla

    2016-04-01

    We study the Hawking radiation of non-asymptotically flat rotating linear dilaton black holes, which are the solutions to the 4D Einstein-Maxwell-dilaton-axion action by using the semi-classical radiation spectrum method. Using scalar perturbations, we show that both angular and radial equations produce exact analytical solutions. Thus, we obtain a precise radiation spectrum for the rotating linear dilaton black hole. The high-frequency regime does not yield the standard Hawking temperature of this black hole computed from the surface gravity. However, we show in detail that the specific low-frequency band of the radiation spectrum allows for the original Hawking temperature of the rotating linear dilaton black hole. The computations are also exhibited graphically.

  6. Hawking Modes And The Optimal Jumbler: Lessons On Unitarity

    CERN Document Server

    Koohbor, Javad; Tavanfar, Alireza

    2015-01-01

    Based on an 'observer-centric methodology' which is conceptually and operationally most direct, we pinpoint the most basic origin of the spectral Planckianity of the asymptotic Hawking modes, which is generic to the conventional treatments of the evolving horizons. Analyzing spacetimes marked by the sole virtue of possessing causal horizons, we clarify in details how this spectral Planckianity is geometrically imposed on the exponentially-redshifted propagating Hawking modes through a 'holographically-illicit' 'jumbling mechanism' which is developed by an environment of the 'curvature modes' in the causal patch of the asymptotic observer. We verify that this mechanism is stable under broad variations of geometries, topologies and categories of the causal horizons, in all the Minkoswki, dS and AdS asymptotics. In the continuation, we elucidate the underlying microscopic physics of the actual phenomenon of the Hawking evaporation of causal horizons. The description is based on a novel holographic scheme of grav...

  7. Space Use by Swainson’s Hawk (Buteo swainsoni in the Natomas Basin, California

    Directory of Open Access Journals (Sweden)

    E. Fleishman

    2016-04-01

    Full Text Available We used satellite-based remote sensing to estimate home ranges for Swainson’s Hawk, a species listed as threatened in California (USA, on its breeding grounds in the Natomas Basin (northern Central Valley, California and to evaluate whether the species’ space-use intensity (statistically derived density of telemetry locations was associated with land cover, sex, reproductive success, or life stage of offspring. We differentiated seven classes of land cover—alfalfa, annually rotated irrigated crops, developed, grassland, orchard / vineyard, rice, and water. From 2011–2013, we fitted transmitters with global positioning systems to 23 adult Swainson’s Hawks. We recorded a minimum of six locations per day per bird from spring through early autumn of each year. We used a fixed, bivariate-normal kernel estimator to calculate a utilization distribution at 30-m resolution for each life stage of each individual within each year. We used a linear mixed model to estimate the associations between intensity of space use and land cover, sex, and reproductive status. The majority of adult Swainson’s Hawks traveled distances up to 8–10 km from the nest throughout the breeding season. Median seasonal home-range sizes in a given year ranged from 87–172 km2. The association between intensity of space use and grassland was 50–139% stronger, and the association between intensity of space use and alfalfa 23–59% stronger, than the associations between intensity of space use and any other land-cover type. Intensity of space use did not vary as a function of sex, reproductive status, or life stage. Given our results and additional knowledge of the species’ ecology, we suggest that reproductive success and, in turn, population-level recruitment may be associated equally if not more closely with availability of nesting sites than with the current distribution of land cover.

  8. Atherosclerosis and ischemic cardiomyopathy in a captive, adult red-tailed hawk (Buteo jamaicensis).

    Science.gov (United States)

    Shrubsole-Cockwill, Alana; Wojnarowicz, Chris; Parker, Dennilyn

    2008-09-01

    An adult, male, captive red-tailed hawk (Buteo jamaicensis) of at least 19 years of age presented in dorsal recumbency. The hawk was nonresponsive, and despite initial supportive care, died shortly after presentation. Gross postmortem revealed no abnormal findings. Histologic examination demonstrated atherosclerosis and ischemic cardiomyopathy. This is the first reported case of atherosclerosis in a red-tailed hawk.

  9. Toxoplasma gondii infections in red-tailed hawks inoculated orally with tissue cysts.

    Science.gov (United States)

    Lindsay, D S; Dubey, J P; Blagburn, B L

    1991-04-01

    The response to inoculation of Toxoplasma gondii tissue cysts was examined in 3 red-tailed hawks (Buteo jamaicensis). One hawk (hawk 1) was inoculated orally with 3.000 tissue cysts of the GT-1 isolate of T. gondii and 2 hawks (hawks 2 and 3) each were inoculated orally with 12,000 tissue cysts of a mixture of 8 isolates of T. gondii. None of the hawks developed clinical signs of toxoplasmosis. Serum antibodies were measured with the modified direct agglutination test using formalin-fixed tachyzoites. Hawk 1 had a titer of 1:40 prior to inoculation and did not have an increase in titer during the study. Hawks 2 and 3 had titers of 1:5 and 1:10, respectively, prior to inoculation, and both had increased titers (titers greater than or equal to 1:60) by 1 wk postinoculation and remained T. gondii antibody positive throughout the 10 wk of the study. Toxoplasma gondii was isolated from the heart and breast muscle of hawk 1. The biologic behavior of this T. gondii isolate was different from the 1 inoculated, and it probably represents a prior natural infection. Toxoplasma gondii was isolated from the brain, heart, breast muscle, and a mixture of gizzard and proventriculus from hawk 2 and from breast muscle of hawk 3. Toxoplasma gondii was not isolated from the eye, lung, liver, kidney, or spleen of any red-tailed hawk.

  10. A 38-year Summary of Raptor Banding at Hawk Ridge, Duluth, Minnesota, USA

    Science.gov (United States)

    Consistent banding of raptors at Hawk Ridge was initiated in 1972 and has continued for 38 years to the present. A total of 99,505 raptors or 2,619 per year have been banded at Hawk Ridge including 23 different species. The majority of birds banded were Sharp-shinned Hawks (Acci...

  11. Fairness and Reciprocity in the Hawk-Dove Game

    DEFF Research Database (Denmark)

    Poulsen, Anders; Neugebauer, Tibor; Schram, Arthur

    2002-01-01

    We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field.......We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field....

  12. Cyanide poisoning of a Cooper’s hawk (Accipiter cooperii)

    Science.gov (United States)

    Franson, J. Christian

    2017-01-01

    A Cooper’s hawk (Accipiter cooperii) was found dead in a ditch leading from a heap leach pad at a gold mine in Nevada. Observations at autopsy included an absence of external lesions, traces of subcutaneous and coronary fat, no food in the upper gastrointestinal tract, and no lesions in the viscera. Cyanide concentrations (µg/g ww) were 5.04 in blood, 3.88 in liver, and 1.79 in brain. No bacteria or viruses were isolated from tissues, and brain cholinesterase activity was within the normal range for a Cooper’s hawk.

  13. Tunnelling Effect and Hawking Radiation from a Vaidya Black Hole

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-Yi; ZHAO Zheng

    2006-01-01

    @@ We extend Parikh's study to the non-stationary black hole. As an example of the non-stationary black hole, we investigate the tunnelling effect and Hawking radiation from a Vaidya black hole whose Bondi mass is identical to its mass parameter. The Hawking radiation is considered as a tunnelling process across the event horizon and we calculate the tunnelling probability. It is found that the result is different from Parikh's study because drH/dv is the function of Bondi mass m(v).

  14. Hawking radiation with dispersion: the broadened horizon paradigm

    CERN Document Server

    Coutant, Antonin

    2014-01-01

    We study the spatial properties of the modes responsible for the Hawking effect in the presence of high frequency dispersion. Near the horizon, the modes are regularized on a small distance which only depends on the surface gravity and the scale of dispersion. The regularization explains why the spectrum is hardly affected by dispersion as long as the background geometry does not significantly vary over this composite length. For relevant frequencies, the regularization differs from the usual WKB resolution of wave singularity near a turning point. The latter only applies when the frequency is so high that the Hawking effect is negligible.

  15. Quantum Signature of Analog Hawking Radiation in Momentum Space.

    Science.gov (United States)

    Boiron, D; Fabbri, A; Larré, P-É; Pavloff, N; Westbrook, C I; Ziń, P

    2015-07-10

    We consider a sonic analog of a black hole realized in the one-dimensional flow of a Bose-Einstein condensate. Our theoretical analysis demonstrates that one- and two-body momentum distributions accessible by present-day experimental techniques provide clear direct evidence (i) of the occurrence of a sonic horizon, (ii) of the associated acoustic Hawking radiation, and (iii) of the quantum nature of the Hawking process. The signature of the quantum behavior persists even at temperatures larger than the chemical potential.

  16. Hawking radiation from gravity's rainbow via gravitational anomaly

    Institute of Scientific and Technical Information of China (English)

    Zeng Xiao-Xiong; Yang Shu-Zheng; Chen De-You

    2008-01-01

    Based on the anomaly cancellation method,initiated by Robinson and Wilczek,we investigates Hawking radiation from the modified Schwarzschild black hole from gravity's rainbow from the anomaly point of view.Unlike the general Schwarzschild space-time,the metric of this black hole depends on the energies of probes.The obtained result shows to restore the underlying general covariance at the quantum level in the effective field,the covariant compensating flux of energy-momentum tensor,which is related to the energies of the probes,should precisely equal to that of a (1+1)-dimensional blackbody at the Hawking temperature.

  17. Dirac Particles' Hawking Radiation from a Schwarzschild Black Hole

    Institute of Scientific and Technical Information of China (English)

    HE Xiao-Kai; LIU Wen-Biao

    2007-01-01

    @@ Considering energy conservation and the backreaction of particles to spacetime, we investigate the massless/massive Dirac particles' Hawking radiation from a Schwarzschild black hole. The exact expression of the emission rate near the horizon is obtained and the result indicates that Hawking radiation spectrum is not purely thermal. The result obtained is consistent with the results obtained before. It satisfies the underlying unitary theory and offers a possible mechanism to explain the information loss paradox. Whereas the improved Damour-Ruffini method is more concise and understandable.

  18. ACES: The ASCENDS CarbonHawk Experiment Simulator

    Science.gov (United States)

    Obland, M. D.; Prasad, N. S.; Harrison, F. W.; Browell, E. V.; Ismail, S.; Dobler, J. T.; Moore, B.; Zaccheo, T.; Campbell, J.; Chen, S.; Cleckner, C. S.; DiJoseph, M.; Little, A.; Notari, A.; Refaat, T. F.; Rosenbaum, D.; Vanek, M. D.; Bender, J.; Braun, M.; Chavez-Pirson, A.; Neal, M.; Rayner, P. J.; Rosiewicz, A.; Shure, M.; Welch, W.

    2012-12-01

    The ASCENDS CarbonHawk Experiment Simulator (ACES) is a NASA Langley Research Center project funded by NASA's Earth Science Technology Office (ESTO) Instrument Incubator Program (IIP) that seeks to advance technologies critical to measuring atmospheric column carbon dioxide (CO2) mixing ratios in support of the NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. The technologies being advanced are: (1) a high bandwidth detector, (2) a multi-aperture telescope assembly, (3) advanced algorithms for cloud and aerosol discrimination, and (4) high-efficiency, multiple-amplifier CO2 and O2 laser transmitters. The instrument architecture will be developed to operate on a high-altitude aircraft and will be directly scalable to meet the ASCENDS mission requirements. These technologies are viewed as critical towards developing an airborne simulator and eventual spaceborne instrument with lower size, mass, and power consumption, and improved performance. The detector effort will improve the existing detector subsystem by increasing its bandwidth to a goal of 5 MHz, reducing its overall mass from 18 lbs to stretching the duration of autonomous, service-free operation periods from 4 hrs to >24 hrs. The development goals are to permit higher laser modulation rates, which provides greater flexibility for implementing thin-cloud discrimination algorithms as well as improving range resolution and error reduction, and to enable long flights on a high-altitude unmanned aerial vehicle (UAV). The telescope development consists of a three-telescope design built for the constraints of the Global Hawk aircraft. This task addresses the ability of multiple smaller telescopes to provide equal or greater collection efficiency compared with a single larger telescope with a reduced impact on launch mass and cost. The telescope assembly also integrates fiber-coupled transmit collimators for all of the laser transmitters and fiber-coupled optical signal output

  19. Grip and Pinch Strength Norms for Michigan Workers

    Directory of Open Access Journals (Sweden)

    Joel M. Phillips M.S., OTRL

    2013-06-01

    Full Text Available The purpose of this study was to create a norm reference of current grip and pinch strength norms for working-age Michigan adults. This normative study included a convenience sample of 179 volunteers who were employees at car plants in South East Michigan or hospital sites in West Michigan. Participants’ ages ranged from between 20 and 62 years of age with a mean age of 49.15 years. There were 78 females (44% and 101 males (56%. Subjects were classified by gender and in the age categories of ages 20 to 49 years and ages 50-62 years. Grip and pinch strength norms were collected following the American Society of Hand Therapy protocol. The norms from these working adults were calculated with descriptive statistics for males and females in two age classifications: ages 20 to 49 and ages 50 to 62 years. Standard Errors (SE are better than the 1985 norms for both males and females ages 20 to 49 years. SEs are higher than the ages 20 to 49 years’ norms for the ages 50 to 62 years age categories in both males and females. These norms offer a point of comparison for clinicians to use for clients in Michigan who are ages 20 to 62 years and who have a goal to improve their grip strength. Clients’ grip and pinch strength could be compared to their age level or gender norms using the comparison for one standard deviation above, below, or at the means.

  20. Gripped by movies: From story-world to artifact absorption

    NARCIS (Netherlands)

    Doicaru, M.M.

    2016-01-01

    That movies are a great source of entertainment seems to be common sense. But how exactly movies manage to get large audiences absorbed, or what is their gripping tool is still a mystery. Research makes use of different concepts pointing to narrative absorption, but it is not clear how they differ f

  1. Soft shape-adaptive gripping device made from artificial muscle

    Science.gov (United States)

    Hamburg, E.; Vunder, V.; Johanson, U.; Kaasik, F.; Aabloo, A.

    2016-04-01

    We report on a multifunctional four-finger gripper for soft robotics, suitable for performing delicate manipulation tasks. The gripping device is comprised of separately driven gripping and lifting mechanisms, both made from a separate single piece of smart material - ionic capacitive laminate (ICL) also known as artificial muscle. Compared to other similar devices the relatively high force output of the ICL material allows one to construct a device able to grab and lift objects exceeding multiple times its own weight. Due to flexible design of ICL grips, the device is able to adapt the complex shapes of different objects and allows grasping single or multiple objects simultaneously without damage. The performance of the gripper is evaluated in two different configurations: a) the ultimate grasping strength of the gripping hand; and b) the maximum lifting force of the lifting actuator. The ICL is composed of three main layers: a porous membrane consisting of non-ionic polymer poly(vinylidene fluoride-co-hexafluoropropene) (PVdF-HFP), ionic liquid 1-ethyl-3-methylimidazolium trifluoromethane-sulfonate (EMITFS), and a reinforcing layer of woven fiberglass cloth. Both sides of the membrane are coated with a carbonaceous electrode. The electrodes are additionally covered with thin gold layers, serving as current collectors. Device made of this material operates silently, requires low driving voltage (<3 V), and is suitable for performing tasks in open air environment.

  2. Hand Grip Strength Vs. Sprint Effectiveness in Amputee Soccer Players

    Directory of Open Access Journals (Sweden)

    Wieczorek Marta

    2015-12-01

    Full Text Available Amputee soccer is one of the types of soccer designed for the disabled, especially those who have undergone amputations, as well as those with extremity dysfunction. The objective of the study was to find the relationship between hand grip strength and sprint time in amputee soccer players. Thirteen field amputee soccer players participated in the study. A SAEHAN hydraulic hand dynamometer manufactured by Jamar was used for hand grip strength measurements. The sprint running test was conducted over a distance of 30 m. The Fusion Smart Speed System was employed for running time measurements. No statistically significant relationships were found between hand grip strength of the left or right hand, and sprint times over 1, 5, 10, 15, 20, 25 and 30 m. Analysis of the running velocity curve of the subjects showed an interesting profile characterized by a 15 meter-long acceleration phase and a significant velocity increase over a distance of 20 – 25 m. The study suggests that there is no relationship between hand grip strength and sprint effectiveness in amputee soccer players. The specificity of locomotion with the use of elbow crutches among elite Polish amputee soccer players probably accounts for the profile of the sprint velocity curve. Extension of the acceleration phase in the sprint run and a velocity increase in the subsequent part of the run were observed.

  3. Effect of wrist position on young adults pinch grip control

    Directory of Open Access Journals (Sweden)

    Vanessa Luzia Barros de Andrade

    2015-12-01

    Full Text Available Pinch grip is used in a large number of handling activities that require precision and control of an object. The position of the upper arm joints affects the fingers force production in order to handle the object. This study aimed to verify the influence of the wrist position in the production of maximum strength and in the control fingers grip pinch submaximum strength control. Participants were 21 right handed adults (10 male, 18-26 years old. They made two attempts of maximum force production and eight attempts of submaximal force production (four at 20% and four at 40% of maximum strength for pinch grip in three wrist positions: neutral, flexion and extension. The results showed that the production of maximum strength is higher in neutral position compared to wrist flexion and extension and higher for men compared to women. In addition, there was a positive correlation between the length of the hand and the production of maximum strength. The results also indicated that the wrist position did not interfere in the submaximum force control during this task. However, participants showed more difficulty controlling 20% than 40% of maximum strength. The present study showed evidence that the motor units used to produce grip pinch maximum strength cross the wrist joint but those used for the 20% and 40% of maximum strength are present only in the fingers and hand.

  4. Are life history events of a northern breeding population of Cooper's Hawks influenced by changing climate?

    Science.gov (United States)

    Rosenfield, Robert N; Hardin, Madeline G; Bielefeldt, John; Keyel, Edward R

    2017-01-01

    Numerous studies have demonstrated earlier timing of spring migration and egg-laying in small passerines, but documentation of such responses to recent climate change in the life histories of higher trophic feeding birds such as raptors is relatively scarce. Raptors may be particularly susceptible to possible adverse effects of climate change due to their longer generation turnover times and lower reproductive capacity, which could lead to population declines because of an inability to match reproductive timing with optimal brood rearing conditions. Conversely adaptively favorable outcomes due to the influence of changing climate may occur. In general, birds that seasonally nest earlier typically have higher reproductive output compared to conspecifics that nest later in the season. Given the strong seasonal decline in reproductive output, and the heritability of nesting phenology, it is possible that nesting seasons would (adaptively) advance over time. Recent climate warming may release prior ecological constraints on birds that depend on food availability at the time of egg production, as do various raptors including Cooper's Hawks (Accipiter cooperii). Under this scenario, productivity, especially clutch size, might increase because it is likely that this reproductive demographic may be the most immediate response to the earlier seasonal presence of food resources. We demonstrated a statistically significant shift of about 4-5 days to an earlier timing of egg-hatching in spring across 36 years during 1980-2015 for a partially migratory population of Cooper's Hawks in Wisconsin, United States, which is consistent with a recent study that showed that Cooper's Hawks had advanced their timing of spring migration during 1979-2012. Both studies occurred in the Great Lakes region, an area that compared to global averages is experiencing earlier and increased warming particularly in the spring in Wisconsin. The nesting period did not lengthen. We suggest that the

  5. On the remote sensing of Hawking grey pulses

    OpenAIRE

    Rosu, H. C.

    1994-01-01

    This is a short note on the black hole remote-sensing problem, i.e., finding out `surface' temperature distributions of various types of small (micron-sized) black holes from the spectral measurements of their Hawking grey pulses. Chen's modified Moebius inverse transform is illustrated in this context

  6. Kas inimkond näeb aastat 2106? / Stephen Hawking

    Index Scriptorium Estoniae

    Hawking, Stephen W., 1942-

    2006-01-01

    Briti füüsik Stephen Hawking avas Yahoo! internetifoorumis debati, küsides foorumikasutajatelt: "Maailmas valitseb poliitiline, sotsiaalne ja ökoloogiline kaos - kuidas suudab inimkond järgmised sada aastat üle elada?". Kommenteerivad julgeolekuekspert Eerik-Niiles Kross, meditsiiniteaduste doktor Mari Järvelaid ja keskkonnaekspert Marek Strandberg

  7. Black Hawk. The Story of an American Indian.

    Science.gov (United States)

    Cunningham, Maggi

    Born in 1767, Black Hawk was the last great war leader of the Sauk Indians, who lived in the Rock River valley in Illinois. By age 25, he was a famed warrior and leader of his people who raided neighboring tribes until a period of peace and prosperity began about 1800. Various treaties of which the Sauk knew and understood very little deprived the…

  8. Kas inimkond näeb aastat 2106? / Stephen Hawking

    Index Scriptorium Estoniae

    Hawking, Stephen W., 1942-

    2006-01-01

    Briti füüsik Stephen Hawking avas Yahoo! internetifoorumis debati, küsides foorumikasutajatelt: "Maailmas valitseb poliitiline, sotsiaalne ja ökoloogiline kaos - kuidas suudab inimkond järgmised sada aastat üle elada?". Kommenteerivad julgeolekuekspert Eerik-Niiles Kross, meditsiiniteaduste doktor Mari Järvelaid ja keskkonnaekspert Marek Strandberg

  9. Hawking-Hayward quasi-local energy under conformal transformations

    CERN Document Server

    Prain, Angus; Faraoni, Valerio; Lapierre-Léonard, Marianne

    2015-01-01

    We derive a formula describing the transformation of the Hawking-Hayward quasi-local energy under a conformal rescaling of the spacetime metric. A known formula for the transformation of the Misner-Sharp-Hernandez mass is recovered as a special case.

  10. Hawking radiation via tunnelling from general stationary axisymmetric black holes

    Institute of Scientific and Technical Information of China (English)

    Zhang Jing-Yi; Fan Jun-Hui

    2007-01-01

    Hawking radiation is viewed as a tunnelling process. In this way the emission rates of massless particles and massive particles tunnelling across the event horizon of general stationary axisymmetric black holes are calculated,separately. The emission spectra of these two different kinds of outgoing particles have the same functional form and both are consistent with an underlying unitary theory.

  11. Comment on 'Hawking radiation from fluctuating black holes'

    NARCIS (Netherlands)

    Khavkine, I.

    2010-01-01

    Takahashi and Soda (2010 Class. Quantum Grav. 27 175008) have recently considered the effect (at lowest non-trivial order) of dynamical, quantized gravitational fluctuations on the spectrum of scalar Hawking radiation from a collapsing Schwarzschild black hole. However, due to an unfortunate choice

  12. Red-shouldered hawk nesting habitat preference in south Texas

    Science.gov (United States)

    Strobel, Bradley N.; Boal, Clint W.

    2010-01-01

    We examined nesting habitat preference by red-shouldered hawks Buteo lineatus using conditional logistic regression on characteristics measured at 27 occupied nest sites and 68 unused sites in 2005–2009 in south Texas. We measured vegetation characteristics of individual trees (nest trees and unused trees) and corresponding 0.04-ha plots. We evaluated the importance of tree and plot characteristics to nesting habitat selection by comparing a priori tree-specific and plot-specific models using Akaike's information criterion. Models with only plot variables carried 14% more weight than models with only center tree variables. The model-averaged odds ratios indicated red-shouldered hawks selected to nest in taller trees and in areas with higher average diameter at breast height than randomly available within the forest stand. Relative to randomly selected areas, each 1-m increase in nest tree height and 1-cm increase in the plot average diameter at breast height increased the probability of selection by 85% and 10%, respectively. Our results indicate that red-shouldered hawks select nesting habitat based on vegetation characteristics of individual trees as well as the 0.04-ha area surrounding the tree. Our results indicate forest management practices resulting in tall forest stands with large average diameter at breast height would benefit red-shouldered hawks in south Texas.

  13. Ambiguity of the equivalence principle and Hawking's temperature

    NARCIS (Netherlands)

    Hooft, G. 't

    1984-01-01

    There are two inequivalent ways in which the laws of physics in a gravitational field can be related to the laws in an inertial frame, when quantum mechanical effects are taken into account. This leads to an ambiguity in the derivation of Hawking's radiation temperature for a black hole: it could be

  14. Hawking Radiation via Tunnelling from Arbitrarily Dimensional Schwarzschild Black Holes

    Institute of Scientific and Technical Information of China (English)

    REN Jun; ZHAO Zheng; GAO Chang-Jun

    2005-01-01

    @@ We extend Parikh's recent work to the arbitrarily dimensional Schwarzschild black holes whose Arnowitt-DeserMisner (ADM) mass is identical to its mass parameter. We view Hawking radiation as a tunnelling process across the event horizon. From the tunnelling probability we also find a leading correction to the semiclassical emission rate. The result consists with an underlying unitary theory.

  15. Stephen Hawking bags big new 3m physics prize

    Science.gov (United States)

    Johnston, Hamish

    2013-01-01

    A massive 3m in prize money has gone to the British cosmologist Stephen Hawking for his work on black holes, quantum gravity and the early universe. The award is one of two "special fundamental physics prizes" from the Fundamental Physics Prize Foundation, which was set up earlier this year by the Russian physicist-turned-entrepreneur Yuri Milner.

  16. The Captivity Narrative as Propaganda in the Black Hawk War.

    Science.gov (United States)

    Fisher, Darlene E.

    1987-01-01

    Shows how captivity stories acted as propaganda against the American Indians in the nineteenth century. Gives excerpts from a captivity narrative portraying Indians in a negative way and demonstrates its use as propaganda during the time of the Black Hawk War. (AEM)

  17. On Hawking Radiation of 3D Rotating Hairy Black Holes

    CERN Document Server

    Belhaj, A; Moumni, H EL; Masmar, K; Sedra, M B

    2015-01-01

    We study the Hawking radiation of 3D rotating hairy black holes. More concretely, we compute the transition probability of a bosonic and fermionic particle in such backgrounds. Thew, we show that the transition probability is independent of the nature of the particle. It is observed that the charge of the scalar hair B and the rotation parameter a control such a probability.

  18. Hawking's singularity theorem for $C^{1,1}$-metrics

    CERN Document Server

    Kunzinger, Michael; Stojkovic, Milena; Vickers, James A

    2014-01-01

    We provide a detailed proof of Hawking's singularity theorem in the regularity class $C^{1,1}$, i.e., for spacetime metrics possessing locally Lipschitz continuous first derivatives. The proof uses recent results in $C^{1,1}$-causality theory and is based on regularisation techniques adapted to the causal structure.

  19. Kajian Kritis Terhadap Praanggapan Metafisis-Epistemologis Kosmologi Stephen Hawking

    OpenAIRE

    2008-01-01

    Tulisan ini pada dasarnya merupakan kajian filosofis terhadap suatu "kosmologi ilmiah".Dengan demikian terdapat dua pendekatan yang digunakan,yakni,pertama,hampiran filsafatilmu, terkait dengan aspek-aspek metodologis dari kosmologi ilmiah;dan kedua, hampirankosmologi filsafat, terkait dengan evaluasi kritis atas kosmologi Hawking dalam dimensikosmologi filsafati, terutama berkenaan dengan posisi yang diambinya terhadap unsur hakikipembangun realitas dan peran pengkosmos di dalamnya khususnya...

  20. Supplier Education--Deere & Company Partners with Black Hawk College.

    Science.gov (United States)

    Lundquist, Linda

    1997-01-01

    Describes the partnership between Deere & Company and Black Hawk College that provided a training program for John Deere suppliers, resulting in a cost-effective approach to upgrading supplier skills and improving Deere product quality. Lists benefits of supplier development and training. (YKH)

  1. The Javan Hawk-eagle : misconceptions about rareness and threat

    NARCIS (Netherlands)

    Balen, van S.; Nijman, V.; Prins, H.H.T.

    2000-01-01

    The Javan hawk-eagle (Spizaetus bartelsi) is a threatened raptor endemic to the densely populated island of Java. Historically very little is known about its biology. Recent surveys showed that the population size has been underestimated in the past. The breeding population is estimated to be

  2. Comparison of the breeding biology of sympatric red-tailed Hawks, White-tailed Hawks, and Crested Caracaras in south Texas

    Science.gov (United States)

    Actkinson, M.A.; Kuvlesky, W.P.; Boal, C.W.; Brennan, L.A.; Hernandez, F.

    2009-01-01

    We compared the breeding biology of sympatric nesting Red-tailed Hawks (Buteo jamaicensis), White-tailed Hawks (Buteo albicaudatus), and Crested Caracaras (Caracara cheriway) in south Texas during 2003 and 2004. We monitored 46 breeding attempts by Red-tailed Hawks, 56 by White-tailed Hawks, and 27 by Crested Caracaras. Observed nesting success was similar for Red-tailed Hawks (62%) and Crested Caracaras (61%), but lower for White-tailed Hawks (51%). Daily survival rates (0.99) were the same for all three species. Red-tailed Hawks and White-tailed Hawks both fledged 1.13 young per nesting pair and Crested Caracaras fledged 1.39 young per nesting pair. All three species nested earlier in 2004 than in 2003; in addition, the overall nesting density of these three species almost doubled from 2003 (1.45 pairs/km2) to 2004 (2.71 pairs/km2). Estimated productivity of all three species was within the ranges reported from other studies. Given extensive and progressive habitat alteration in some areas of south Texas, and the limited distributions of White-tailed Hawks and Crested Caracaras, the presence of large ranches managed for free-range cattle production and hunting leases likely provides important habitat and may be key areas for conservation of these two species. ?? 2009 The Raptor Research Foundation, Inc.

  3. Globalization

    DEFF Research Database (Denmark)

    Plum, Maja

    Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...

  4. Effects of hyperthyroidism on hand grip strength and function.

    Science.gov (United States)

    Erkol İnal, Esra; Çarlı, Alparslan Bayram; Çanak, Sultan; Aksu, Oğuzhan; Köroğlu, Banu Kale; Savaş, Serpil

    2015-01-01

    Hyperthyroidism is a pathologic condition in which the body is exposed to excessive amounts of circulating thyroid hormones. Skeletal muscle is one of the major target organs of thyroid hormones. We evaluated hand grip strength and function in patients with overt hyperthyroidism. Fifty-one patients newly diagnosed with hyperthyroidism and 44 healthy controls participated in this study. Age, height, weight, and dominant hand of all participants were recorded. The diagnosis of hyperthyroidism was confirmed by clinical examination and laboratory tests. Hand grip strength was tested at the dominant hand with a Jamar hand dynamometer. The grooved pegboard test (PGT) was used to evaluate hand dexterity. The Duruöz Hand Index (DHI) was used to assess hand function. No significant differences were found in terms of clinical and demographic findings between the patients with hyperthyroidism and healthy controls (p > 0.05). Significant differences were found between the patients with hyperthyroidism and healthy controls regarding PGT and DHI scores (p Hyperthyroidism seemed to affect hand dexterity and function more than hand grip strength and seemed to be associated with reduced physical function more than muscle strength. This may also indicate that patients with hyperthyroidism should be evaluated by multidisplinary modalities.

  5. GRIPS - Gamma-Ray Imaging, Polarimetry and Spectroscopy

    CERN Document Server

    Greiner, J; Aharonian, F; Ajello, M; Balasz, L G; Barbiellini, G; Bellazzini, R; Bishop, S; Bisnovatij-Kogan, G S; Boggs, S; Bykov, A; DiCocco, G; Diehl, R; Elsässer, D; Foley, S; Fransson, C; Gehrels, N; Hanlon, L; Hartmann, D; Hermsen, W; Hillebrandt, W; Hudec, R; Iyudin, A; Jose, J; Kadler, M; Kanbach, G; Klamra, W; Kiener, J; Klose, S; Kreykenbohm, I; Kuiper, L M; Kylafis, N; Labanti, C; Langanke, K; Langer, N; Larsson, S; Leibundgut, B; Laux, U; Longo, F; Maeda, K; Marcinkowski, R; Marisaldi, M; McBreen, B; McBreen, S; Meszaros, A; Nomoto, K; Pearce, M; Peer, A; Pian, E; Prantzos, N; Raffelt, G; Reimer, O; Rhode, W; Ryde, F; Schmidt, C; Silk, J; Shustov, B M; Strong, A; Tanvir, N; Thielemann, F -K; Tibolla, O; Tierney, D; Trümper, J; Varshalovich, D A; Wilms, J; Wrochna, G; Zdziarski, A; Zoglauer, A

    2011-01-01

    We propose to perform a continuously scanning all-sky survey from 200 keV to 80 MeV achieving a sensitivity which is better by a factor of 40 or more compared to the previous missions in this energy range. The Gamma-Ray Imaging, Polarimetry and Spectroscopy (GRIPS) mission addresses fundamental questions in ESA's Cosmic Vision plan. Among the major themes of the strategic plan, GRIPS has its focus on the evolving, violent Universe, exploring a unique energy window. We propose to investigate $\\gamma$-ray bursts and blazars, the mechanisms behind supernova explosions, nucleosynthesis and spallation, the enigmatic origin of positrons in our Galaxy, and the nature of radiation processes and particle acceleration in extreme cosmic sources including pulsars and magnetars. The natural energy scale for these non-thermal processes is of the order of MeV. Although they can be partially and indirectly studied using other methods, only the proposed GRIPS measurements will provide direct access to their primary photons. G...

  6. 3-minute Stephen Hawking. His life, theories and influence; Stephen Hawking im 3-Minuten-Takt. Sein Leben, sein Werk, sein Einfluss

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, Paul; Dixon, Gail

    2013-09-01

    3-minutes Stephen Hawking offers a compact introduction to life and work of this impressing scientist. This book is devided into three parts: Hawking's life, his theories, his influence. Each part offers fascinating reading material for one hour. The partial themes of this book are served up in practical 3-minute portions.

  7. Technology advancement for the ASCENDS mission using the ASCENDS CarbonHawk Experiment Simulator (ACES)

    Science.gov (United States)

    Obland, M. D.; Antill, C.; Browell, E. V.; Campbell, J. F.; CHEN, S.; Cleckner, C.; Dijoseph, M. S.; Harrison, F. W.; Ismail, S.; Lin, B.; Meadows, B. L.; Mills, C.; Nehrir, A. R.; Notari, A.; Prasad, N. S.; Kooi, S. A.; Vitullo, N.; Dobler, J. T.; Bender, J.; Blume, N.; Braun, M.; Horney, S.; McGregor, D.; Neal, M.; Shure, M.; Zaccheo, T.; Moore, B.; Crowell, S.; Rayner, P. J.; Welch, W.

    2013-12-01

    The ASCENDS CarbonHawk Experiment Simulator (ACES) is a NASA Langley Research Center project funded by NASA's Earth Science Technology Office that seeks to advance technologies critical to measuring atmospheric column carbon dioxide (CO2) mixing ratios in support of the NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. The technologies being advanced are: (1) multiple transmitter and telescope-aperture operations, (2) high-efficiency CO2 laser transmitters, (3) a high bandwidth detector and transimpedance amplifier (TIA), and (4) advanced algorithms for cloud and aerosol discrimination. The instrument architecture is being developed for ACES to operate on a high-altitude aircraft, and it will be directly scalable to meet the ASCENDS mission requirements. The above technologies are critical for developing an airborne simulator and spaceborne instrument with lower platform consumption of size, mass, and power, and with improved performance. This design employs several laser transmitters and telescope-apertures to demonstrate column CO2 retrievals with alignment of multiple laser beams in the far-field. ACES will transmit five laser beams: three from commercial lasers operating near 1.57-microns, and two from the Exelis atmospheric oxygen (O2) fiber laser amplifier system operating near 1.26-microns. The Master Oscillator Power Amplifier at 1.57-microns measures CO2 column concentrations using an Integrated-Path Differential Absorption (IPDA) lidar approach. O2 column amounts needed for calculating the CO2 mixing ratio will be retrieved using the Exelis laser system with a similar IPDA approach. The three aperture telescope design was built to meet the constraints of the Global Hawk high-altitude unmanned aerial vehicle (UAV). This assembly integrates fiber-coupled transmit collimators for all of the laser transmitters and fiber-coupled optical signals from the three telescopes to the aft optics and detector package. The detector

  8. Hawk-Eyes on Science and in Space

    Science.gov (United States)

    Durow, Lillie

    2017-08-01

    For more than ten years the successful and well received outreach programs, Hawk-Eyes On Science and Hawk-Eyes in Space, have brought the excitement of science demonstrations to Iowans of all ages. However, the creation of a successful, sustainable outreach program requires the coordination of many aspects. In many respects, the demonstrations and hands-on activities are of secondary importance when weighed against the problems of funding, transportation, staffing, etc. In addition to showing examples of demonstrations that we use, I will also focus on a few of the problems and some of the solutions that we have found while coordinating our long running outreach programs at the University of Iowa Department of Physics and Astronomy.

  9. Correction value to charged Bekenstein-Hawking black hole entropy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recently,based on the study of black hole Hawking radiation with the tunnel effect method,we found that the radiation spectrum of the black hole is not a strict pure thermal spectrum. It is a very interesting problem to determine how the departure of the black hole radiation spectrum from the pure thermal spectrum affects entropy. We calculate the partition function by the energy spectrum obtained using tunnel effect. Using the relation between the partition function and entropy,we derive the correction value to Bekenstein-Hawking entropy of the charged black hole. Fur-thermore,we obtain the conditions that various thermodynamic quantities must satisfy,when phase transition of the charged black hole occurs.

  10. Software requirements specification for the HAWK operating system

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, V.P.; Harris, D.L.; Borgman, C.R.; Davidson, G.S.

    1989-03-01

    This document represents the original requirements specification for the HAWK operating system. HAWK is the operating system for the SANDAC V, a real-time embedded multiprocessor based on the Motorola 68020 microprocessor. When the effort to create the operating system was first undertaken, it was clear that a careful specification of the requirements would be vital. Unfortunately, there were few models to work from since requirement documents for operating systems of any kind are seldom published. The final form of the requirements used a functional organization adapted from the IEEE Guide to Software Requirements Specifications (ANSI/IEEE Std 830-1984). Hopefully, this document will provide a historical case study from which others can benefit when faced with similar circumstances. 2 refs., 4 figs.

  11. Hawking Radiation of Linear Dilaton Black Holes in Various Theories

    CERN Document Server

    Pasaoglu, H

    2009-01-01

    Using the Damour-Ruffini-Sannan, the Parikh-Wilczek and the thin film brick-wall models, we investigate the Hawking radiation of uncharged massive particles from 4-dimensional linear dilaton black holes, which are the solutions to Einstein-Maxwell-Dilaton, Einstein-Yang-Mills-Dilaton and Einstein-Yang-Mills-Born-Infeld-Dilaton theories. Our results show that the tunneling rate is related to the change of Bekenstein-Hawking entropy. Contrary to the many studies in the literature, here the emission spectrum is precisely thermal. This implies that the derived emission spectrum is not consistent with the unitarity of the quantum theory, which would possibly lead to the information loss.

  12. Hawking-Moss Tunneling in Noncommutative Eternal Inflation

    CERN Document Server

    Cai, Yi-Fu

    2007-01-01

    The quantum behavior of noncommutative eternal inflation is quite different from the usual knowledge. Unlike the usual eternal inflation, the quantum fluctuation of noncommutative eternal inflation is suppressed by the Hubble parameter. Due to this, we need to reconsider many conceptions of eternal inflation. In this paper we study the Hawking-Moss tunneling in noncommutative eternal inflation using the stochastic approach. We obtain a brand-new form of the tunneling probability for this process and find that the Hawking-Moss tunneling is more unlikely to take place in the noncommutative case than in the usual one. We also conclude that the lifetime of a metastable de-Sitter (dS) vacuum in the noncommutative spacetime is longer than that in the commutative case.

  13. Toxicity of gentamicin in red-tailed hawks.

    Science.gov (United States)

    Bird, J E; Walser, M M; Duke, G E

    1983-07-01

    Gentamicin sulfate at dosage levels of 10 and 20 mg/kg of body weight was administered twice daily IV to red-tailed hawks. Clinical signs, water consumption, and changes in blood chemical values were monitored. Tissues were examined grossly and ultrastructurally, using light and electron microscopy. Clinical signs of weakness and apnea were attributed to gentamicin-induced neuromuscular blockade in the 20-mg/kg group. Serum values of aspartate transaminase, alanine transaminase, cholesterol, inorganic phosphorus, total protein, albumin, and uric acid increased in some birds. There was a decrease in periodic acid-Schiff staining of proximal tubular brush borders. Increased numbers of cytoplasmic lysosomes, many of which contained myelin figures, in renal epithelial cells were seen at the ultrastructural level. All birds given 20 mg/kg died. Both dosage levels were considered toxic in red-tailed hawks.

  14. Hawking radiation as perceived by different observers (ERE2011 proceedings)

    CERN Document Server

    Barbado, Luis C; Garay, Luis J

    2012-01-01

    We study the perception of Hawking radiation by different observers outside a black hole. The analysis is done in terms of an effective-temperature function that varies along the trajectory of each observer. The vacuum state of the radiation field is chosen to be non-stationary, so as to mimic the switching-on of Hawking radiation that would appear in a real black hole collapse. We analyse how this vacuum is perceived by observers staying at a fixed radius, by observers coming in free-fall from radial infinity at different times, and by observers in free-fall released from finite radial positions. Results found have a compelling physical interpretation. One main result, at first unexpected, is that in general free-falling observers do perceive particle emission by the black hole when crossing the event horizon. This happens because of a diverging Doppler shift at the event horizon.

  15. Black Hawk Down: Film Zwischen Reflektion und Konstruktion Gesellschaftlicher Wirklichkeit

    Science.gov (United States)

    Pötzsch, Holger

    2009-05-01

    BLACK HAWK DOWN: FILM BETWEEN THE REFLECTION AND CONSTRUCTION OF SOCIAL REALITY - In this article, Ridley Scott's film Black Hawk Down (USA 2001) is read in the context of contemporary theories concerning cultural memory (Jan and Aleida Assmann) and media culture (Douglas Kellner). It is argued that film (and representation in general) does not merely reflect a preceding reality; it also actively serves to construct it. It is shown how Scott's film privileges one particular perspective on an actual event and how this point of view is objectified and installed in the memory of Western media culture. What potential implications does an increased blurring of fact and fiction in the representation of war have? What are the consequences for political and pedagogical practice? What role can cultural studies play in these processes?

  16. Kajian Kritis Terhadap Praanggapan Metafisis-Epistemologis Kosmologi Stephen Hawking

    Directory of Open Access Journals (Sweden)

    Sindung Tjahyadi

    2008-10-01

    Full Text Available Tulisan ini pada dasarnya merupakan kajian filosofis terhadap suatu "kosmologi ilmiah".Dengan demikian terdapat dua pendekatan yang digunakan,yakni,pertama,hampiran filsafatilmu, terkait dengan aspek-aspek metodologis dari kosmologi ilmiah;dan kedua, hampirankosmologi filsafat, terkait dengan evaluasi kritis atas kosmologi Hawking dalam dimensikosmologi filsafati, terutama berkenaan dengan posisi yang diambinya terhadap unsur hakikipembangun realitas dan peran pengkosmos di dalamnya khususnya terkait dengan konsepruang-wakru, prinsip determinisme, dan hukum kekekalan energi.

  17. Steven Hawking to visit Texas A&M in spring

    CERN Multimedia

    Xavier, D

    2002-01-01

    Stephen Hawking will visit Texas A&M University from Feb. 24 to March 21 2003 to participate in the inaugural meeting of the George P. and Cynthia W. Mitchell Institute for Fundamental Physics. This institute will bring several of the world's top physicists to A&M for a month-long exploration of the latest ideas on topics ranging from superstrings to M-theory and supergravity (1/2 page).

  18. Trend detection in social networks using Hawkes processes

    OpenAIRE

    2015-01-01

    International audience; —We develop in this paper a trend detection algorithm , designed to find trendy topics being disseminated in a social network. We assume that the broadcasts of messages in the social network is governed by a self-exciting point process, namely a Hawkes process, which takes into consideration the real broadcasting times of messages and the interaction between users and topics. We formally define trendiness and derive trend indices for each topic being disseminated in th...

  19. Top scientists join Stephen Hawking at Perimeter Institute

    Science.gov (United States)

    Banks, Michael

    2009-03-01

    Nine leading researchers are to join Stephen Hawking as visiting fellows at the Perimeter Institute for Theoretical Physics in Ontario, Canada. The researchers, who include string theorists Leonard Susskind from Stanford University and Asoka Sen from the Harisch-Chandra Research Institute in India, will each spend a few months of the year at the institute as "distinguished research chairs". They will be joined by another 30 scientists to be announced at a later date.

  20. Modulated Hawking radiation and a nonviolent channel for information release

    Directory of Open Access Journals (Sweden)

    Steven B. Giddings

    2014-11-01

    Full Text Available Unitarization of black hole evaporation requires that quantum information escapes a black hole; an important question is to identify the mechanism or channel by which it does so. Accurate counting of black hole states via the Bekenstein–Hawking entropy would indicate this information should be encoded in radiation with average energy flux matching Hawking's. Information can be encoded with no change in net flux via fine-grained modulation of the Hawking radiation. In an approximate effective field theory description, couplings to the stress tensor of the black hole atmosphere that depend on the internal state of the black hole are a promising alternative for inducing such modulation. These can be picturesquely thought of as due to state-dependent metric fluctuations in the vicinity of the horizon. Such couplings offer the prospect of emitting information without extra energy flux, and can be shown to do so at linear order in the couplings, with motivation given for possible extension of this result to higher orders. The potential advantages of such couplings to the stress tensor thus extend beyond their universality, which is helpful in addressing constraints from black hole mining.

  1. Critical reflexivity in financial markets: a Hawkes process analysis

    Science.gov (United States)

    Hardiman, Stephen J.; Bercot, Nicolas; Bouchaud, Jean-Philippe

    2013-10-01

    We model the arrival of mid-price changes in the E-mini S&P futures contract as a self-exciting Hawkes process. Using several estimation methods, we find that the Hawkes kernel is power-law with a decay exponent close to -1.15 at short times, less than ≈ 103 s, and crosses over to a second power-law regime with a larger decay exponent ≈-1.45 for longer times scales in the range [ 103,106 ] seconds. More importantly, we find that the Hawkes kernel integrates to unity independently of the analysed period, from 1998 to 2011. This suggests that markets are and have always been close to criticality, challenging a recent study which indicates that reflexivity (endogeneity) has increased in recent years as a result of increased automation of trading. However, we note that the scale over which market events are correlated has decreased steadily over time with the emergence of higher frequency trading.

  2. The Hawking cascade from a black hole is extremely sparse

    CERN Document Server

    Gray, Finnian; Van-Brunt, Alexander; Visser, Matt

    2015-01-01

    The Hawking flux from a black hole, (at least as seen from large distances), is extremely sparse and thin, with the average time between emission of successive Hawking quanta being hundreds of times larger than the natural timescale set by the energies of the emitted quanta. Some aspects of this result have been known for over 30 years, but have been largely forgotten, possibly because authors focussed mainly on the late-time high-temperature regime. We shall instead focus on the early-stage low-temperature regime, and shall both quantify and significantly extend these observations in a number of different ways. First we shall identify several natural dimensionless figures of merit, and thereby compare the mean time between emission of successive Hawking quanta to several quite natural timescales that can be associated with the emitted quanta, demonstrating that ratios of 300 or more are typical for emission of photons or gravitons from a Schwarzschild black hole. Furthermore these ratios are independent of t...

  3. Scaling limits for Hawkes processes and application to financial statistics

    CERN Document Server

    Bacry, Emmanuel; Hoffmann, Marc; Muzy, Jean François

    2012-01-01

    We prove a law of large numbers and a functional central limit theorem for multivariate Hawkes processes observed over a time interval $[0,T]$ in the limit $T \\rightarrow \\infty$. We further exhibit the asymptotic behaviour of the covariation of the increments of the components of a multivariate Hawkes process, when the observations are imposed by a discrete scheme with mesh $\\Delta$ over $[0,T]$ up to some further time shift $\\tau$. The behaviour of this functional depends on the relative size of $\\Delta$ and $\\tau$ with respect to $T$ and enables to give a full account of the second-order structure. As an application, we develop our results in the context of financial statistics. We introduced in a previous work a microscopic stochastic model for the variations of a multivariate financial asset, based on Hawkes processes and that is confined to live on a tick grid. We derive and characterise the exact macroscopic diffusion limit of this model and show in particular its ability to reproduce important empiric...

  4. Hawking Radiation of Scalar and Vector Particles From 5D Myers-Perry Black Holes

    CERN Document Server

    Jusufi, Kimet

    2016-01-01

    In the present paper we explore the Hawking radiation as a quantum tunneling effect from a rotating 5 dimensional Myers-Perry (5D-MPBH) black hole with two independent angular momentum componentes. First, we investigate the Hawking temperature by considering the tunneling of massive scalar particles and spin-1 vector particles from the 5D-MPBH in the Painlev\\'e coordinates and then in the corotating frames. More specifically, we solve the Klein-Gordon and Proca equation by applying the WKB method and Hamilton-Jacobi equation in both cases. Finally, we recover the Hawking temperature and show that coordinates systems do not affect the Hawking temperature.

  5. Hawking Radiation of Scalar and Vector Particles from 5D Myers-Perry Black Holes

    Science.gov (United States)

    Jusufi, Kimet; Övgün, Ali

    2017-06-01

    In the present paper we explore the Hawking radiation as a quantum tunneling effect from a rotating 5 dimensional Myers-Perry black hole (5D-MPBH) with two independent angular momentum components. First, we investigate the Hawking temperature by considering the tunneling of massive scalar particles and spin-1 vector particles from the 5D-MPBH in the Painlevé coordinates and then in the corotating frames. More specifically, we solve the Klein-Gordon and Proca equations by applying the WKB method and Hamilton-Jacobi equation in both cases. Finally, we recover the Hawking temperature and show that coordinates systems do not affect the Hawking temperature.

  6. Hawking Radiation of Scalar and Vector Particles from 5D Myers-Perry Black Holes

    Science.gov (United States)

    Jusufi, Kimet; Övgün, Ali

    2017-02-01

    In the present paper we explore the Hawking radiation as a quantum tunneling effect from a rotating 5 dimensional Myers-Perry black hole (5D-MPBH) with two independent angular momentum components. First, we investigate the Hawking temperature by considering the tunneling of massive scalar particles and spin-1 vector particles from the 5D-MPBH in the Painlevé coordinates and then in the corotating frames. More specifically, we solve the Klein-Gordon and Proca equations by applying the WKB method and Hamilton-Jacobi equation in both cases. Finally, we recover the Hawking temperature and show that coordinates systems do not affect the Hawking temperature.

  7. Observation of quantum Hawking radiation and its entanglement in an analogue black hole

    Science.gov (United States)

    Steinhauer, Jeff

    2016-10-01

    We observe spontaneous Hawking radiation, stimulated by quantum vacuum fluctuations, emanating from an analogue black hole in an atomic Bose-Einstein condensate. Correlations are observed between the Hawking particles outside the black hole and the partner particles inside. These correlations indicate an approximately thermal distribution of Hawking radiation. We find that the high-energy pairs are entangled, while the low-energy pairs are not, within the reasonable assumption that excitations with different frequencies are not correlated. The entanglement verifies the quantum nature of the Hawking radiation. The results are consistent with a driven oscillation experiment and a numerical simulation.

  8. The Hawking evaporation process of rapidly-rotating black holes: an almost continuous cascade of gravitons

    Energy Technology Data Exchange (ETDEWEB)

    Hod, Shahar [The Ruppin Academic Center, Emek Hefer (Israel); The Hadassah Institute, Jerusalem (Israel)

    2015-07-15

    It is shown that rapidly-rotating Kerr black holes are characterized by the dimensionless ratio τ{sub gap}/τ{sub emission} = O(1), where τ{sub gap} is the average time gap between the emissions of successive Hawking quanta and τ{sub emission} is the characteristic timescale required for an individual Hawking quantum to be emitted from the black hole. This relation implies that the Hawking cascade from rapidly-rotating black holes has an almost continuous character. Our results correct some inaccurate claims that recently appeared in the literature regarding the nature of the Hawking black-hole evaporation process. (orig.)

  9. Hawking Radiation via Damour-Ruffini Method in Squashed Charged Rotating Kaluza-Klein Black Holes

    Science.gov (United States)

    Hu, Ji-Wan; Wu, Jing-He; Liu, Xian-Ming

    2017-02-01

    Using the Damour-Ruffini method, Hawking radiation of charged particles from squashed charged rotating five-dimensional Kaluza-Klein black holes is investigated extensively. Under the generalized tortoise coordinate transformation, Hawking temperature of the black holes is calculated by using charged scalar particles and Dirac fermions respectively. We find that the obtained Hawking temperature for charged Dirac fermions is the same as for charged scalar particles. What's more, the spectrum of Hawking radiation contains the information of the size of the extra dimension, which could provide insight for further investigation of large extra dimensions in the future.

  10. Brachial plexus injury in two red-tailed hawks (Buteo jamaicensis).

    Science.gov (United States)

    Shell, L; Richards, M; Saunders, G

    1993-01-01

    Two red-tailed hawks (Buteo jamaicensis), found near Deltaville, Virginia (USA), were evaluated because of inability to use a wing. Results of needle electromyographic studies of the affected wing muscles in both hawks were compatible with denervation. On euthanasia, one hawk had extensive axon and myelin loss with multifocal perivascular lymphocytic inflammation of its brachial plexus and radial nerve. Demyelination and axon loss in the dorsal white matter of the spinal cord on the affected side also were found at the origin of the brachial plexus. The other hawk's wing had not returned to functional status > 2 yr after injury.

  11. Information-carrying Hawking radiation and the number of microstate for a black hole

    CERN Document Server

    Cai, Qing-yu; You, Li

    2016-01-01

    We present a necessary and sufficient condition to falsify whether a Hawking radiation spectrum indicates unitary emission process or not from the perspective of information theory. With this condition, we show the precise values of Bekenstein-Hawking entropies for Schwarzschild black holes and Reissner-Nordstr\\"om black holes can be calculated by counting the microstates of their Hawking radiations. In particular, for the extremal Reissner-Nordstr\\"om black hole, its number of microstate and the corresponding entropy we obtain are found to be consistent with the string theory results. Our finding helps to refute the dispute about the Bekenstein-Hawking entropy of extremal black holes in the semiclassical limit.

  12. Effect of object width on precision grip force and finger posture.

    Science.gov (United States)

    Domalain, M; Vigouroux, L; Danion, F; Sevrez, V; Berton, E

    2008-09-01

    This study aimed to define the effect of object width on spontaneous grasp. Participants held objects of various masses (0.75 to 2.25 kg) and widths (3.5 to 9.5 cm) between thumb and index finger. Grip force, maximal grip force and corresponding finger postures were recorded using an embedded force sensor and an optoelectronic system, respectively. Results showed that index finger joints varied to accommodate the object width, whereas thumb posture remained constant across conditions. For a given object mass, grip force increased as a function of object width, although this result is not dictated by the laws of mechanics. Because maximal grip force also increased with object width, we hypothesise that participants maintain a constant ratio between grip force and their maximal grip force at each given width. Altogether we conclude that when the task consists in manipulating objects/tools, the optimal width is different than when maximal force exertions are required.

  13. Effects of Sensory Deficit on Phalanx Force Deviation During Power Grip Post Stroke.

    Science.gov (United States)

    Enders, Leah R; Seo, Na Jin

    2017-01-01

    The effect of sensory deficits on power grip force from individual phalanges was examined. The authors found that stroke survivors with sensory deficits (determined by the Semmes-Weinstein monofilament test) gripped with phalanx force directed more tangential to the object surface, than those without, although both groups had similar motor deficits (Chedoke-McMaster and Fugl-Meyer), grip strength, and skin friction. Altered grip force direction elevates risk of finger slippage against the object thus grip loss/object dropping, hindering activities of daily living. Altered grip force direction was associated with altered muscle activation patterns. In summary, the motor impairment level alone may not describe hand motor control in detail. Information about sensory deficits helps elucidate patients' hand motor control with functional relevance.

  14. Discrimination of handlebar grip samples by fourier transform infrared microspectroscopy analysis and statistics

    Directory of Open Access Journals (Sweden)

    Zeyu Lin

    2017-01-01

    Full Text Available In this paper, the authors presented a study on the discrimination of handlebar grip samples, to provide effective forensic science service for hit and run traffic cases. 50 bicycle handlebar grip samples, 49 electric bike handlebar grip samples, and 96 motorcycle handlebar grip samples have been randomly collected by the local police in Beijing (China. Fourier transform infrared microspectroscopy (FTIR was utilized as analytical technology. Then, target absorption selection, data pretreatment, and discrimination of linked samples and unlinked samples were chosen as three steps to improve the discrimination of FTIR spectrums collected from different handlebar grip samples. Principal component analysis and receiver operating characteristic curve were utilized to evaluate different data selection methods and different data pretreatment methods, respectively. It is possible to explore the evidential value of handlebar grip residue evidence through instrumental analysis and statistical treatments. It will provide a universal discrimination method for other forensic science samples as well.

  15. ANALYTICAL RESEARCH ON THE GRIP VARIATION OF TWO-AXLE CAR

    Directory of Open Access Journals (Sweden)

    Rosen IVANOV

    2016-12-01

    Full Text Available This paper presents a theoretical investigation on the decrease in grip coefficient of a car due to the car mass changes for three different running conditions- straightforward, motion in curve and braking. The grip of two types of cars - with forward and rear traction, equipped with three models of tires are studied. The results show a significant decrease of the grip coefficient in longitudinal and lateral directions.

  16. Control of Precision Grip Force in Lifting and Holding of Low-Mass Objects.

    Directory of Open Access Journals (Sweden)

    Yuichi Hiramatsu

    Full Text Available Few studies have investigated the control of grip force when manipulating an object with an extremely small mass using a precision grip, although some related information has been provided by studies conducted in an unusual microgravity environment. Grip-load force coordination was examined while healthy adults (N = 17 held a moveable instrumented apparatus with its mass changed between 6 g and 200 g in 14 steps, with its grip surface set as either sandpaper or rayon. Additional measurements of grip-force-dependent finger-surface contact area and finger skin indentation, as well as a test of weight discrimination, were also performed. For each surface condition, the static grip force was modulated in parallel with load force while holding the object of a mass above 30 g. For objects with mass smaller than 30 g, on the other hand, the parallel relationship was changed, resulting in a progressive increase in grip-to-load force (GF/LF ratio. The rayon had a higher GF/LF force ratio across all mass levels. The proportion of safety margin in the static grip force and normalized moment-to-moment variability of the static grip force were also elevated towards the lower end of the object mass for both surfaces. These findings indicate that the strategy of grip force control for holding objects with an extremely small mass differs from that with a mass above 30 g. The data for the contact area, skin indentation, and weight discrimination suggest that a decreased level of cutaneous feedback signals from the finger pads could have played some role in a cost function in efficient grip force control with low-mass objects. The elevated grip force variability associated with signal-dependent and internal noises, and anticipated inertial force on the held object due to acceleration of the arm and hand, could also have contributed to the cost function.

  17. Finger pad friction and its role in grip and touch

    Science.gov (United States)

    Adams, Michael J.; Johnson, Simon A.; Lefèvre, Philippe; Lévesque, Vincent; Hayward, Vincent; André, Thibaut; Thonnard, Jean-Louis

    2013-01-01

    Many aspects of both grip function and tactile perception depend on complex frictional interactions occurring in the contact zone of the finger pad, which is the subject of the current review. While it is well established that friction plays a crucial role in grip function, its exact contribution for discriminatory touch involving the sliding of a finger pad is more elusive. For texture discrimination, it is clear that vibrotaction plays an important role in the discriminatory mechanisms. Among other factors, friction impacts the nature of the vibrations generated by the relative movement of the fingertip skin against a probed object. Friction also has a major influence on the perceived tactile pleasantness of a surface. The contact mechanics of a finger pad is governed by the fingerprint ridges and the sweat that is exuded from pores located on these ridges. Counterintuitively, the coefficient of friction can increase by an order of magnitude in a period of tens of seconds when in contact with an impermeably smooth surface, such as glass. In contrast, the value will decrease for a porous surface, such as paper. The increase in friction is attributed to an occlusion mechanism and can be described by first-order kinetics. Surprisingly, the sensitivity of the coefficient of friction to the normal load and sliding velocity is comparatively of second order, yet these dependencies provide the main basis of theoretical models which, to-date, largely ignore the time evolution of the frictional dynamics. One well-known effect on taction is the possibility of inducing stick–slip if the friction decreases with increasing sliding velocity. Moreover, the initial slip of a finger pad occurs by the propagation of an annulus of failure from the perimeter of the contact zone and this phenomenon could be important in tactile perception and grip function. PMID:23256185

  18. Grip strength in healthy caucasian adults: reference values.

    Science.gov (United States)

    Günther, Christian M; Bürger, Alexander; Rickert, Markus; Crispin, Alexander; Schulz, Christoph U

    2008-04-01

    The aim of this study was to update reference data of handgrip strength for healthy adults of both genders spanning a wide age range and to analyze possible factors of influence. Intraindividual and interindividual variations of grip strength and their relation to several anthropometric factors were analyzed in a standardized manner for 769 healthy adults (women, n = 403; men, n = 366) aged between 20 years and 95 years. Measurements were done in neutral position of arm, forearm, and wrist on setting II of a Baseline digital hydraulic dynamometer (NexGen Ergonomics Inc. Quebec, Canada). Mean strength was about 41% less in women (right 29 kg; left 27 kg) than in men (right 49 kg; left 47 kg) resulting in a ratio of left to right hand slightly above .95 in both genders. During the course of life, hand strength develops comparably in both genders peaking at 35 years of age and decreasing continuously further on. Anthropometric variables such as forearm circumference and length, hand size, or body mass showed a positive correlation with grip strength. Body mass index, type of work, and hand dominance showed only a partial positive correlation or no correlation with grip strength. Gender and age, followed by parameters representing body length and obesity, were observed to have the highest predictive value for handgrip strength and were therefore entered into the generation of prediction equations. We recommend side adjustment of measured values for intraindividual comparison and inclusion of information regarding anthropometric characteristics, as well as using gender- and age-adjusted reference values, whereas hand dominance can be neglected. The regression equations we generated might prove to be useful for clinicians or for those who use normative values within software to provide more accurate predictions of strength scores for specific applications.

  19. GRIPS - Gamma-Ray Burst Investigation via Polarimetry and Spectroscopy

    CERN Document Server

    Greiner, J

    2008-01-01

    The primary scientific goal of the GRIPS mission is to revolutionize our understanding of the early universe using gamma-ray bursts. We propose a new generation gamma-ray observatory capable of unprecedented spectroscopy over a wide range of gamma-ray energies (200 keV--50 MeV) and of polarimetry (200--1000 keV). Secondary goals achievable by this mission include direct measurements of supernova interiors through gamma-rays from radioactive decays, nuclear astrophysics with massive stars and novae, and studies of particle acceleration near compact stars, interstellar shocks, and clusters of galaxies.

  20. GRIP Database original data - GRIPDB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us GRIPDB GRIP Database original data Data detail Data name GRIP Database original data DOI 10....18908/lsdba.nbdc01665-006 Description of data contents GRIP Database original data It consists of data table...s and sequences. Data file File name: gripdb_original_data.zip File URL: ftp://ftp.biosciencedbc.jp/archive/gripdb/LATEST/gripdb_orig...e Database Description Download License Update History of This Database Site Policy | Contact Us GRIP Database original data - GRIPDB | LSDB Archive ... ...inal_data.zip File size: 779 KB Simple search URL - Data

  1. Pencil grips, legibility, and speed of fourth-graders' writing in cursive.

    Science.gov (United States)

    Koziatek, Susan M; Powell, Nancy J

    2003-01-01

    The purpose of this research was to study how the speed and legibility of fourth-graders handwriting was affected by type of pencil grip on the Evaluation Tool of Children's Handwriting-Cursive. Ninety-five typically developing students and 6 students receiving special education services completed the Evaluation Tool of Children's Handwriting-Cursive (ETCH-C). Photographs were taken of their pencil grips while they wrote the alphabet. One-way ANOVAs were calculated to compare legibility rates and writing speeds by type of pencil grip. Ninety-nine of the students used one of four pencil grips including the dynamic tripod (38 students), the dynamic quadrupod (18), the lateral tripod (22), and the lateral quadrupod (21). One student used the four-finger pencil grip and one used the interdigital pencil grip. Mean cursive writing speeds were similar for all pencil grips except for the interdigital grasp. Speeds obtained were slower than recently published fourth-grade speeds ranging from a mean of 29.45 to 34.75 letters per minute. CONCLUSION. This study found the lateral quadrupod and four-finger pencil grips to be as functional as the dynamic tripod, lateral tripod, and dynamic quadrupod pencil grips. This study provides average handwriting speeds for fourth-grade students on the ETCH-C.

  2. Delayed grip relaxation and altered modulation of intracortical inhibition with aging

    Science.gov (United States)

    Motawar, Binal; Stinear, James W.; Lauer, Abigail W.; Ramakrishnan, V. Viswanathan; Seo, Na Jin

    2015-01-01

    Grip relaxation is a voluntary action that requires an increase in short-interval intracortical inhibition (SICI) in healthy young adults, rather than a simple termination of excitatory drive. The way aging affects this voluntary inhibitory action and timing of grip relaxation is currently unknown. The objective of this study was to examine aging-related delays in grip relaxation and SICI modulation for the flexor digitorum superficialis (FDS) muscle during grip relaxation. The main finding was that young adults increased SICI to relax their grips, whereas older adults did not increase SICI with a prolonged grip relaxation time (prelaxation time). A secondary experiment showed that both young and older adults did not change H reflex excitability during grip relaxation. Our data suggest that grip relaxation is mediated by increased cortical inhibitory output in young adults, and aging-related impairment in increasing cortical inhibitory output may hamper timely cessation of muscle activity. Our data also suggest a lesser role of the spinal circuits in grip muscle relaxation. This knowledge may contribute to understanding of aging-related movement deterioration and development of interventions for improving modulation of SICI to improve muscle relaxation and movement coordination. PMID:26686531

  3. Comparative study of maximum isometric grip strength in different sports

    Directory of Open Access Journals (Sweden)

    Noé Gomes Borges Junior

    2009-06-01

    Full Text Available The objective of this study was to compare maximum isometric grip strength (Fmaxbetween different sports and between the dominant (FmaxD and non-dominant (FmaxND hand. Twenty-nine male aikido (AI, jiujitsu (JJ, judo (JU and rowing (RO athletes and 21non-athletes (NA participated in the study. The hand strength test consisted of maintainingmaximum isometric grip strength for 10 seconds using a hand dynamometer. The position of the subjects was that suggested by the American Society of Hand Therapy. Factorial 2X5 ANOVA with Bonferroni correction, followed by a paired t test and Tukey test, was used for statistical analysis. The highest Fmax values were observed for the JJ group when using the dominant hand,followed by the JU, RO, AI and NA groups. Variation in Fmax could be attributed to handdominance (30.9%, sports modality (39.9% and the interaction between hand dominance andsport (21.3%. The present results demonstrated significant differences in Fmax between the JJ and AI groups and between the JJ and NA groups for both the dominant and non-dominant hand. Significant differences in Fmax between the dominant and non-dominant hand were only observed in the AI and NA groups. The results indicate that Fmax can be used for comparisonbetween different sports modalities, and to identify differences between the dominant and nondominanthand. Studies involving a larger number of subjects will permit the identification of differences between other modalities.

  4. Grip pressure measurements during activities of daily life

    Science.gov (United States)

    Sanford, Joe; Young, Carolyn; Popa, Dan; Bugnariu, Nicoleta; Patterson, Rita

    2014-06-01

    Research has expanded human-machine communication methods past direct programming and standard hand- held joystick control. Individual force sensors have been used as a simple means of providing environmental information to a robot and research has shown that more advanced sensitive skins can be viable input devices. These touch sensitive surfaces allow for additional modes of interaction between machines in open, undefined environments. These interactions include object detection for navigation and safety but can also be used for recognition of users command gestures by their machine partner. Key to successful implementation of these gestures is the understanding of varied strategies used for communication and interaction and the development of performance limits. Data of dominant hand grip forces was collected using a Tekscan Grip VersaTek Pressure Measurement System during opening of a door. Analysis of data from 10 male and female subjects is presented. The results of qualitative and quantitative analysis of these data show variability in hand configurations between users. Average data over the cohort is reported. These data will be used in future work to provide human metrology constraints and limits for use in simulation and design of new, physical human-robot interaction systems.

  5. Comparative study of millennials' (age 20-34 years) grip and lateral pinch with the norms.

    Science.gov (United States)

    Fain, Elizabeth; Weatherford, Cara

    Cross-sectional research design. Clinical practice continues to use normative data for grip and pinch measurements that were established in 1985. There is no updated norms despite different hand usage patterns in today's society. Measuring and comparing grip and pinch strengths with normative data is a valid method to determine hand function. This research was implemented to compare the grip and pinch measurements obtained from healthy millennials to the established norms and to describe hand usage patterns for millennials. Grip and lateral pinch measurements were obtained from a sample of 237 healthy millennials (ages 20-34 years). Strength scores were statistically lower that older normative data in all millennial grip strengths, with the exception of the women in the age group of 30-34 years. Specifically, this statistically significant trend was observed in all male grip strengths, as well as in women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). However, the lateral pinch data reflected was similar to the older norms with variances of 0.5-1 kg. Current data reflect statistically significant differences from the norms for all male grip measurements, as well as for women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). No statistical significance was observed in the independent-sample t tests for the lateral pinch in men of all age groups. Statistical significance was noted for lateral pinch for female age groups for the left hand (20-24 years) and for bilateral lateral pinches (30-34 years). IV. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  6. Hawking radiation of scalar particles from accelerating and rotating black holes

    Energy Technology Data Exchange (ETDEWEB)

    Gillani, Usman A.; Rehman, Mudassar; Saifullah, K., E-mail: mani_precious2001@yahoo.com, E-mail: mudassar051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

    2011-06-01

    Hawking radiation of uncharged and charged scalar particles from accelerating and rotating black holes is studied. We calculate the tunneling probabilities of these particles from the rotation and acceleration horizons of these black holes. Using this method we recover the correct Hawking temperature as well.

  7. Low prevalence of Trichomonas gallinae in urban and migratory Cooper's Hawks in northcentral North America

    Science.gov (United States)

    Rosenfield, Robert N.; Taft, Stephen J.; Stout, William E.; Driscoll, Timothy G.; Evans, David L.; Bozek, Michael A.

    2009-01-01

    Trichomoniasis is a digestive tract disease caused by ingestion of the protozoan Trichomonas gallinae. This disease can be a significant source of mortality. No deaths of nestlings could be attributed to trichomoniasis in Cooper's Hawks (Accipiter cooperii) breeding in urban and rural environs in Wisconsin, North Dakota, and British Columbia. We detected T. gallinae in four (5.2%) of 77 nestling Cooper's Hawks during 2006 and 2007 among 42 urban nests on new study areas in southeast Wisconsin and eastern North Dakota/western Minnesota. All four infected young fledged. We did not detect T. gallinae in 52 breeding adult Cooper's Hawks on two urban study sites, nor in 28 migrant hatching year (n  =  24) and adult (n  =  4) Cooper's Hawks at Hawk Ridge Nature Reserve, Duluth, Minnesota in 2006–2007. Overall, we detected T. gallinae in only 2.5% of 157 Cooper's Hawks in northcentral North America. These results suggest a low prevalence of T. gallinae in Cooper's Hawks in the northern part of this hawk's breeding range.

  8. Hawking radiation from Kerr-Newman de Sitter black hole via anomalies

    Institute of Scientific and Technical Information of China (English)

    Lin Kai; Yang Shu-Zheng; Zeng Xiao-Xiong

    2008-01-01

    In this paper, Hawking radiation from the Kerr-Newman de Sitter black hole is studied via gauge anomaly and gravitational anomaly. The obtained results of Hawking radiation from the event horizon and the cosmological horizon accord with those by other methods.

  9. Health evaluation of Galapagos Hawks (Buteo galapagoensis) on Santiago Island, Galapagos.

    Science.gov (United States)

    Deem, Sharon L; Rivera-Parra, Jose Luis; Parker, Patricia G

    2012-01-01

    Galapagos Hawks (Buteo galapagoensis), the only endemic, diurnal raptor species in Galapagos, are currently distributed on eight Galapagos Islands having been extirpated from three of the human-inhabited islands. In January 2009, we performed health assessments of 89 Galapagos Hawks on Santiago Island, Galapagos. Four of the 89 Galapagos Hawks (4%) evaluated had physical abnormalities. Blood parameters did not differ between males and females, except for aspartate transaminase values, which were significantly higher in females than males. No Galapagos Hawks tested positive for antibodies to avian encephalitis virus, Marek virus, and paramyxovirus-1 or to haemosporidian antigen. Chlamydophila psittaci antigen was detected in 2 of 86 Galapagos Hawks (2%), with 24 of 43 Galapagos Hawks (56%) antibody-positive for avian adenovirus-1 and 1 of 48 Galapagos Hawks (2%) antibody positive for Toxoplasma gondii. There were no significant differences in infectious disease results based on sex. This study contributes to the understanding of the health status of the Galapagos Hawk and to the establishment of baseline information for the species.

  10. Autumn raptor banding at hawk Ridge, Duluth, Minnesota USA, 1972-2009: An overview

    Science.gov (United States)

    This manuscript is targeted to a specialized audience: ornithologists who work specifically on raptors (hawks and owls). The goal of the paper is to describe the last 38 years of banding at Hawk Ridge Bird Observatory and to put out some preliminary results on species’ annual dy...

  11. Horsfield's hawk-cuckoo nestlings simulate multiple gapes for begging.

    Science.gov (United States)

    Tanaka, Keita D; Ueda, Keisuke

    2005-04-29

    Nestlings of some brood parasitic birds evict hosts' eggs and young soon after hatching, thereby avoiding discrimination by hosts while monopolizing parental care. Eviction carries a cost, however, because lone parasitic nestlings attract a reduced provisioning rate. Here we describe a form of visual signaling used by the evicting Horsfield's hawk-cuckoo (Cuculus fugax) to obtain sufficient food. The chick displays a gape-colored patch on the wing to the host parents as they deliver food, simulating the gaping display of more than one nestling.

  12. Hawking radiation from a five-dimensional Lovelock black hole

    CERN Document Server

    Saleh, Mahamat; Crepin, Kofane Timoleon

    2016-01-01

    We investigate Hawking radiation from a five-dimensional Lovelock black hole using the Hamilton-Jacobi method. The behavior of the rate of radiation is plotted for various values of the ultraviolet correction parameter and the cosmological constant. The results show that, owing to the ultraviolet correction and the presence of dark energy represented by the cosmological constant, the black hole radiates at a slower rate in comparison to the case without ultraviolet correction or cosmological constant. Moreover, the presence of the cosmological constant makes the effect of the ultraviolet correction on the black hole radiation negligible.

  13. Lorentz Invariance Violation and Modified Hawking Fermions Tunneling Radiation

    Directory of Open Access Journals (Sweden)

    Shu-Zheng Yang

    2016-01-01

    Full Text Available Recently the modified Dirac equation with Lorentz invariance violation has been proposed, which would be helpful to resolve some issues in quantum gravity theory and high energy physics. In this paper, the modified Dirac equation has been generalized in curved spacetime, and then fermion tunneling of black holes is researched under this correctional Dirac field theory. We also use semiclassical approximation method to get correctional Hamilton-Jacobi equation, so that the correctional Hawking temperature and correctional black hole’s entropy are derived.

  14. Perspectiva narrativa sobre HISTORIA DEL TIEMPO, de Stephen Hawking

    OpenAIRE

    García Landa, José Angel

    2011-01-01

    Reseña con resumen y comentario de HISTORIA DEL TIEMPO, de Stephen Hawking, sintetizando las tesis principales del libro y evaluándolas desde el punto de vista de una filosofía del tiempo (tanto cósmico como humano) informada por la teoría narrativa y la filosofía evolucionista. Cualquier historia o teoría del tiempo, por compleja que sea, ha de volverse más complicada una vez se tiene en cuenta el papel de las descripciones, modelos y teorías en tanto que instrumentos cognitivos históricamen...

  15. Diabetes mellitus in a red-tailed hawk (Buteo jamaicensis).

    Science.gov (United States)

    Wallner-Pendleton, E A; Rogers, D; Epple, A

    1993-09-01

    An adult, free-living female red-tailed hawk (Buteo jamaicensis) with clinical signs of generalized weakness, polyuria, and polydipsia, was killed and necropsied. An ante mortem serum sample taken from the bird contained 54.3 mmole/1 glucose, and large amounts of glucose were found in the urine. At necropsy, the pancreas was small, pale pink with multiple, round, approximately 0.5 mm white foci. Light and electron microscopic examination of the pancreas revealed markedly vacuolated islet cells. Histochemical examination of the tissue showed that the vacuolated cells were beta-cells. This is the first report of spontaneously occurring diabetes mellitus in a raptor.

  16. Kolmogorov-Sinai and Bekenstein-Hawking entropies

    CERN Document Server

    Ropotenko, K

    2007-01-01

    It is shown that instability of stringy matter near the event horizon of a black hole (the spreading effect) can be characterized by the Lyapunov exponents. For a homogeneous and isotropic horizon the (average) Lyapunov exponent coincides with the Kolmogorov-Sinai entropy of stringy matter. Due to identity of phase space volume of the string with the area of the horizon the relation between the Kolmogorov-Sinai and Bekenstein-Hawking entropies is established. The Kolmogorov-Sinai entropy measures the rate at which information about the string state is lost as the string spreads over the horizon.

  17. Bekenstein-Hawking Entropy as Topological Entanglement Entropy

    OpenAIRE

    McGough, Lauren; Verlinde, Herman

    2013-01-01

    Black holes in 2+1 dimensions enjoy long range topological interactions similar to those of non-abelian anyon excitations in a topologically ordered medium. Using this observation, we compute the topological entanglement entropy of BTZ black holes, via the established formula S_top = log(S^a_0), with S_b^a the modular S-matrix of the Virasoro characters chi_a(tau). We find a precise match with the Bekenstein-Hawking entropy. This result adds a new twist to the relationship between quantum ent...

  18. Caryospora uptoni and Frenkelia sp.-like coccidial infections in red-tailed hawks (Buteo borealis).

    Science.gov (United States)

    Lindsay, D S; Blagburn, B L

    1989-07-01

    The feces from 16 red-tailed hawks (Buteo borealis) were examined by fecal flotation for the presence of coccidial oocysts or sporocysts. Oocysts of Caryospora uptoni were found in five (31%), sporocysts of a Frenkelia sp.-like coccidium were found in eight (50%), and mixed infections with both species of coccidia were found in three (19%) red-tailed hawks. Neither oocysts nor sporocysts were found in six (38%) red-tailed hawks. Sexual stages of C. uptoni were found in the duodenum and jejunum of a naturally infected red-tailed hawk. Sexual stages were located in enterocytes on the distal three-fourths of the villi. This study shows that over 60% of red-tailed hawks may be passing coccidial oocysts/sporocysts in their feces and provides morphological information for diagnosing C. uptoni infections in histological sections.

  19. The Effect of Handedness on Grip Strength in Older Adults with Intellectual Disabilities

    Science.gov (United States)

    Oppewal, Alyt; Hilgenkamp, Thessa I. M.; van Wijck, Ruud; Evenhuis, Heleen M.

    2013-01-01

    Grip strength is an important predictor of several health outcomes in the general older population. Grip strength assessment is feasible and reliable in older adults with intellectual disabilities (ID), which makes it a valuable measurement for application in this population. The purpose of this study was to investigate the effect of handedness on…

  20. Children with flat feet have weaker toe grip strength than those having a normal arch

    Science.gov (United States)

    Tashiro, Yuto; Fukumoto, Takahiko; Uritani, Daisuke; Matsumoto, Daisuke; Nishiguchi, Shu; Fukutani, Naoto; Adachi, Daiki; Hotta, Takayuki; Morino, Saori; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Aoyama, Tomoki

    2015-01-01

    [Purpose] This study investigated the relationship between toe grip strength and foot posture in children. [Subjects and Methods] A total of 619 children participated in this study. The foot posture of the participants was measured using a foot printer and toe grip strength was measured using a toe grip dynamometer. Children were classified into 3 groups; flatfoot, normal, and high arch, according to Staheli’s arch index. The differences in demographic data and toe grip strength among each foot posture group were analyzed by analysis of variance. Additionally, toe grip strength differences were analyzed by analysis of covariance, adjusted to body mass index, age, and gender. [Results] The number of participants classified as flatfoot, normal, and high arch were 110 (17.8%), 468 (75.6%), and 41 (6.6%), respectively. The toe grip strength of flatfoot children was significantly lower than in normal children, as shown by both analysis of variance and analysis of covariance. [Conclusion] A significant difference was detected in toe grip strength between the low arch and normal foot groups. Therefore, it is suggested that training to increase toe grip strength during childhood may prevent the formation of flat feet or help in the development of arch. PMID:26696732

  1. Biomimetics approach for methods to release microobjects from the gripping tool

    DEFF Research Database (Denmark)

    Gegeckaite, Asta; Moon, Jack; Hansen, Hans Nørgaard

    2005-01-01

    In the micro scale, gripping devices are working in the different way. New forces, working in the micro scale, like van der Waals, surface tension and electrostatics are influencing the gripping process. Handling of micro or even nano sized objects can be easily in the nature. Different types of ...

  2. Getting a Grip on Numbers: Numerical Magnitude Priming in Object Grasping

    Science.gov (United States)

    Lindemann, Oliver; Abolafia, Juan M.; Girardi, Giovanna; Bekkering, Harold

    2007-01-01

    To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small numbers, whereas power grips were initiated…

  3. 16 CFR Figure 5 to Part 1512 - Typical Handbrake Actuator Showing Grip Dimension

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Typical Handbrake Actuator Showing Grip Dimension 5 Figure 5 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS... Actuator Showing Grip Dimension EC03OC91.072 ...

  4. Biomimetics approach for methods to release microobjects from the gripping tool

    DEFF Research Database (Denmark)

    Gegeckaite, Asta; Moon, Jack; Hansen, Hans Nørgaard

    2005-01-01

    In the micro scale, gripping devices are working in the different way. New forces, working in the micro scale, like van der Waals, surface tension and electrostatics are influencing the gripping process. Handling of micro or even nano sized objects can be easily in the nature. Different types of ...

  5. Hand grip strength in patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Jeong M

    2017-08-01

    Full Text Available Moa Jeong,1 Hyung Koo Kang,1 Pamela Song,2 Hye Kyeong Park,1 Hoon Jung,1 Sung-Soon Lee,1 Hyeon-Kyoung Koo1 1Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, 2Department of Neurology, Ilsan Paik Hospital, Inje University College of Medicine, Goyang, Republic of Korea Purpose: Hand grip strength (HGS is a simple way of predicting the risk of cardiovascular disease and all-cause mortality in the general population. However, the practical significance of grip strength in patients with COPD is uncertain. The aim of this study was to compare HGS between subjects with and without COPD and to evaluate its clinical relevance in patients with COPD by using a national survey.Methods: Data were collected from the Korean National Health and Nutrition Examination Survey. The study included 421 adults with COPD and 2,542 controls who completed questionnaires, spirometry, and a HGS test. HGS was compared between subjects with and without COPD, and the association between grip strength, lung function, and quality of life (QoL was evaluated.Results: The mean HGS was 33.3±9.1 kg in the COPD group and 29.9±9.5 kg in the non-COPD group; adjusted HGS was 30.9±0.33 kg and 30.9±0.11 kg, respectively (P=0.99. HGS was not related to forced vital capacity (β=0.04, P=0.70 or forced expiratory volume in 1 second (β=0.11, P=0.24 in multivariable analysis. HGS was independently associated with the EQ-5D index, but the relationship was stronger in the COPD group (β=0.30, P<0.001 than in the non-COPD group (β=0.21, P<0.001. The results were similar for each component of the EQ-5D, including mobility (β=-0.25, P<0.001, daily activity (β=-0.19, P=0.01, pain/discomfort (β=-0.32, P<0.001, and anxiety/depression (β=-0.16, P=0.01.Conclusion: HGS was not different between subjects with and without COPD, but was associated with QoL – including mobility, daily activity, pain/discomfort, and anxiety/depression – in patients with COPD. The

  6. TC81220F (HAWK) MPEG 2 system decoder LSI; MPEG2 system decoder LSI TC81220F (HAWK)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Satellite broadcasting, cable broadcasting, and ground wave broadcasting have been digitized gradually. In the video and audio data communication, the MPEG2 (Moving Picture Experts Group 2) technology for compression and extension is important. A system LSI that includes an MPEG2 decoder in a receiving set (Set Top Box) is required to each broadcasting. To deduce the system cost, Toshiba developed a TX3904 MCU (microcontroller) that controls the system, a transport processor that selects the packet-multiplexed data, and TC81220F (HAWK) that puts MPEG2 audio video decoders in one chip. (translated by NEDO)

  7. Force analysis of the rowing stroke employing two differing oar grips.

    Science.gov (United States)

    Bompa, T O; Hebbelinck, M; Van Gheluwe, B

    1985-06-01

    The velocity of the rowing boat appears to depend on the force which the athlete applies at the handle of the oar. Although force is generated by legs, upper body, and arms, the latter are the only limbs which actually transmit and apply the force against the oar. The force output of the arms seem to be a function of the forearm position used by the athlete while gripping the oar. The traditional gripping technique is with the forearms in pronation. This technique was never challenged or scientifically researched to see whatever a modified one might lead to better efficiency. Consequently, the purpose of this investigation was to analyze whether athletes' force output differed if the gripping technique was changed from pronation to a semiprone grip (one arm prone, the other semiprone). Under the specific conditions of this investigation it was demonstrated that the semiprone position was generating greater force output, thus being superior to the classical prone grip.

  8. Hawking radiation and classical tunneling: A ray phase space approach

    Science.gov (United States)

    Tracy, E. R.; Zhigunov, D.

    2016-01-01

    Acoustic waves in fluids undergoing the transition from sub- to supersonic flow satisfy governing equations similar to those for light waves in the immediate vicinity of a black hole event horizon. This acoustic analogy has been used by Unruh and others as a conceptual model for "Hawking radiation." Here, we use variational methods, originally introduced by Brizard for the study of linearized MHD, and ray phase space methods, to analyze linearized acoustics in the presence of background flows. The variational formulation endows the evolution equations with natural Hermitian and symplectic structures that prove useful for later analysis. We derive a 2 × 2 normal form governing the wave evolution in the vicinity of the "event horizon." This shows that the acoustic model can be reduced locally (in ray phase space) to a standard (scalar) tunneling process weakly coupled to a unidirectional non-dispersive wave (the "incoming wave"). Given the normal form, the Hawking "thermal spectrum" can be derived by invoking standard tunneling theory, but only by ignoring the coupling to the incoming wave. Deriving the normal form requires a novel extension of the modular ray-based theory used previously to study tunneling and mode conversion in plasmas. We also discuss how ray phase space methods can be used to change representation, which brings the problem into a form where the wave functions are less singular than in the usual formulation, a fact that might prove useful in numerical studies.

  9. Tunneling method for Hawking radiation in the Nariai case

    Science.gov (United States)

    Belgiorno, F.; Cacciatori, S. L.; Dalla Piazza, F.

    2017-08-01

    We revisit the tunneling picture for the Hawking effect in light of the charged Nariai manifold, because this general relativistic solution, which displays two horizons, provides the bonus to allow the knowledge of exact solutions of the field equations. We first perform a revisitation of the tunneling ansatz in the framework of particle creation in external fields à la Nikishov, which corroborates the interpretation of the semiclassical emission rate Γ_{emission} as the conditional probability rate for the creation of a couple of particles from the vacuum. Then, particle creation associated with the Hawking effect on the Nariai manifold is calculated in two ways. On the one hand, we apply the Hamilton-Jacobi formalism for tunneling, in the case of a charged scalar field on the given background. On the other hand, the knowledge of the exact solutions for the Klein-Gordon equations on Nariai manifold, and their analytic properties on the extended manifold, allow us a direct computation of the flux of particles leaving the horizon, and, as a consequence, we obtain a further corroboration of the semiclassical tunneling picture from the side of S-matrix formalism.

  10. Comparative morphology among northern populations of breeding Cooper's Hawks

    Science.gov (United States)

    Rosenfield, Robert N.; Rosenfield, Laura J.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William E.; Driscoll, Timothy G.; Bozek, Michael A.

    2010-01-01

    Few studies at a broad geographical scale have characterized intraspecific variation in morphology of woodland hawks in the genus Accipiter. From 1999 to 2007 we investigated morphological variation in large samples of live Cooper's Hawks (A. cooperii) nesting in four study areas: coniferous woodland around Victoria, British Columbia, Canada, isolated deciduous woodlands in short-grass prairies of northwestern North Dakota, towns and rural deciduous woodlands along the border of North Dakota and Minnesota, and urban and rural mixed deciduous and coniferous landscapes of Wisconsin. These sites span 2660 km across the northern part of the species' breeding range. We measured body mass (i.e., size), wing chord, tail length, tarsus diameter, hallux length, and culmen length of breeding adults, finding significant and clinal variation in body mass (or size). The smallest and most similar-sized birds occurred in British Columbia and western North Dakota, larger birds along the border between North Dakota and Minnesota, and the largest birds in Wisconsin. Several other characters varied significantly when mass was used as a covariate. Variation by study site in mean indices of sexual size dimorphism was negligible and not significant. We speculate that the morphological differences we found, in part, are the result of geographic isolation, where diets, migratory behavior, and structural characteristics of nesting habitats vary across landscape types.

  11. Modified Bekenstein-Hawking System in f( R) Gravity

    Science.gov (United States)

    Dutta, Jibitesh; Mitra, Saugata; Chetry, Binod

    2016-10-01

    The present work deals with four alternative formulation of Bekenstein system on event horizon in f( R) gravity. While thermodynamical laws holds in universe bounded by apparent horizon, these laws break down on event horizon. With alternative formulation of thermodynamical parameters (temperature and entropy), thermodynamical laws hold on event horizon in Einstein Gravity. With this motivation, we extend the idea of generalised Hawking temperature and modified Bekenstein entropy in homogeneous and isotropic model of universe on event horizon and examine whether thermodynamical laws hold in f(R) gravity. Specifically, we examine and compare validity of generalised second law of thermodynamics (GSLT) and thermodynamical equilibrium (TE) in four alternative modified Bekenstein scenarios. As Dark energy is a possible dominant candidate for matter in the univerese and Holographic Dark Energy (HDE) can give effective description of f(R) gravity, so matter in the universe is taken as in the form interacting HDE. In order to understand the complicated expressions, finally the above laws are examined from graphical representation using three Planck data sets and it is found that generalised/modified Hawking temperature has a crucial role in making perfect thermodynamical system.

  12. Nesting habitat and productivity of Swainson's Hawks in southeastern Arizona

    Science.gov (United States)

    Nishida, Catherine; Boal, Clint W.; DeStefano, Stephen; Hobbs, Royden J.

    2013-01-01

    We studied Swainson's Hawks (Buteo swainsoni) in southeastern Arizona to assess the status of the local breeding population. Nest success (≥1 young fledged) was 44.4% in 1999 with an average of 1.43 ± 0.09 (SE) young produced per successful pair. Productivity was similar in 2000, with 58.2% nesting success and 1.83 ± 0.09 fledglings per successful pair. Mesquite (Prosopis velutina) and cottonwood (Populus fremontii) accounted for >50% of 167 nest trees. Nest trees were taller than surrounding trees and random trees, and overall there was more vegetative cover at nest sites than random sites. This apparent requirement for cover around nest sites could be important for management of the species in Arizona. However, any need for cover at nest sites must be balanced with the need for open areas for foraging. Density of nesting Swainson's Hawks was higher in agriculture than in grasslands and desert scrub. Breeding pairs had similar success in agricultural and nonagricultural areas, but the effect of rapid and widespread land-use change on breeding distribution and productivity continues to be a concern throughout the range of the species.

  13. Effects of carpal tunnel syndrome on dexterous manipulation are grip type-dependent.

    Science.gov (United States)

    Zhang, Wei; Johnston, Jamie A; Ross, Mark A; Sanniec, Kyle; Gleason, Elizabeth A; Dueck, Amylou C; Santello, Marco

    2013-01-01

    Carpal tunnel syndrome (CTS) impairs sensation of a subset of digits. Although the effects of CTS on manipulation performed with CTS-affected digits have been studied using precision grip tasks, the extent to which CTS affects multi-digit force coordination has only recently been studied. Whole-hand manipulation studies have shown that CTS patients retain the ability to modulate multi-digit forces to object mass, mass distribution, and texture. However, CTS results in sensorimotor deficits relative to healthy controls, including significantly larger grip force and lower ability to balance the torques generated by the digits. Here we investigated the effects of CTS on multi-digit force modulation to object weight when manipulating an object with a variable number of fingers. We hypothesized that CTS patients would be able to modulate digit forces to object weight. However, as different grip types involve the exclusive use of CTS-affected digits ('uniform' grips) or a combination of CTS-affected and non-affected digits ('mixed' grips), we addressed the question of whether 'mixed' grips would reduce or worsen CTS-induced force coordination deficits. The former scenario would be due to adding digits with intact tactile feedback, whereas the latter scenario might occur due to a potentially greater challenge for the central nervous system of integrating 'noisy' and intact tactile feedback. CTS patients learned multi-digit force modulation to object weight regardless of grip type. Although controls exerted the same total grip force across all grip types, patients exerted significantly larger grip force than controls but only for manipulations with four and five digits. Importantly, this effect was due to CTS patients' inability to change the finger force distribution when adding the ring and little fingers. These findings suggest that CTS primarily challenges sensorimotor integration processes for dexterous manipulation underlying the coordination of CTS-affected and non

  14. Effects of carpal tunnel syndrome on dexterous manipulation are grip type-dependent.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available Carpal tunnel syndrome (CTS impairs sensation of a subset of digits. Although the effects of CTS on manipulation performed with CTS-affected digits have been studied using precision grip tasks, the extent to which CTS affects multi-digit force coordination has only recently been studied. Whole-hand manipulation studies have shown that CTS patients retain the ability to modulate multi-digit forces to object mass, mass distribution, and texture. However, CTS results in sensorimotor deficits relative to healthy controls, including significantly larger grip force and lower ability to balance the torques generated by the digits. Here we investigated the effects of CTS on multi-digit force modulation to object weight when manipulating an object with a variable number of fingers. We hypothesized that CTS patients would be able to modulate digit forces to object weight. However, as different grip types involve the exclusive use of CTS-affected digits ('uniform' grips or a combination of CTS-affected and non-affected digits ('mixed' grips, we addressed the question of whether 'mixed' grips would reduce or worsen CTS-induced force coordination deficits. The former scenario would be due to adding digits with intact tactile feedback, whereas the latter scenario might occur due to a potentially greater challenge for the central nervous system of integrating 'noisy' and intact tactile feedback. CTS patients learned multi-digit force modulation to object weight regardless of grip type. Although controls exerted the same total grip force across all grip types, patients exerted significantly larger grip force than controls but only for manipulations with four and five digits. Importantly, this effect was due to CTS patients' inability to change the finger force distribution when adding the ring and little fingers. These findings suggest that CTS primarily challenges sensorimotor integration processes for dexterous manipulation underlying the coordination of CTS

  15. Comparison of Infant Car Seat grip orientations and lift strategies.

    Science.gov (United States)

    Clamann, Michael; Zhu, Biwen; Beaver, Leah; Taylor, Kinley; Kaber, David

    2012-07-01

    The rear-facing Infant Car Seat (ICS) is designed to meet federal requirements for transporting children less than 1 year old. Typical use includes transfer in and out of a vehicle, which is shown to be a difficult lift. Despite the frequency of this lift, manufacturers provide little guidance for users. Review of relevant literature suggested an ICS featuring an angled handle, promoting a neutral wrist posture, would increase grip stability and decrease lifting effort. Popular press suggested a foot-in-car stance for the ICS lift would do the same. An experiment was conducted in which wrist deviations from neutral posture were recorded along with lifting muscle activation levels (multiple flexor muscles and biceps brachii) and overall perceived exertion for straight versus a new bent handle design and conventional stance versus foot-in-car. Foot position was examined to test the recommendations in the popular press. Surprisingly, wrist deviation was not significantly affected by the new bent handle design (due to compensatory behavior with the straight handle) but was related to foot placement (p=0.04). Results revealed the bent handle to significantly reduce flexor activation compared with the straight handle (p=0.0003); however, the level of biceps activation increased. Biceps activation also significantly increased for foot-in-car stance (p=0.035) but not flexor activation. In general, the bent handle enabled the user to lift the ICS with a steadier grip and less effort. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. Stephen Hawking's Community-Bound Voice A Functional Investigation of Self-Mentions in Stephen Hawking's Scientific Prose

    Directory of Open Access Journals (Sweden)

    Davud Kuhi

    2015-11-01

    Full Text Available Thanks to the development of the concept of metadiscourse, it is now widely acknowledged that academic/scientific writing is not only concerned with communicating purely propositional meanings: what is communicated through academic/scientific communication is seen to be intertwined with the negotiation of social and interpersonal meanings. While a large number of so called metadiscoursal resources contribute to the simultaneous negotiation of propositional and interpersonal meanings, the present study aimed at investigating the functions self-mention forms can fulfill in academic/scientific communication. Two of Stephen Hawking's scientific books were selected as the corpus of the research, and based on Tang and John's (1999 model, the constructed corpus was analyzed in terms of the functions self-mention forms can fulfill in academic/scientific writing. The findings revealed that from among the different roles identified by Tang and John, the representative role constituted the most frequent self-mention function in the corpus. The remarkably heavy presence of representative role in Hawking's scientific prose was interpreted as a further evidence for the claim that scientists are more likely to persuade readers of their ideas if they frame their messages in ways which appeal to appropriate community-recognized relationships.

  17. Hawking fluxes and anomalies in rotating regular black holes with a time-delay

    Science.gov (United States)

    Takeuchi, Shingo

    2016-11-01

    Based on the anomaly cancellation method we compute the Hawking fluxes (the Hawking thermal flux and the total flux of energy-momentum tensor) from a four-dimensional rotating regular black hole with a time-delay. To this purpose, in the three metrics proposed in [1], we try to perform the dimensional reduction in which the anomaly cancellation method is feasible at the near-horizon region in a general scalar field theory. As a result we can demonstrate that the dimensional reduction is possible in two of those metrics. Hence we perform the anomaly cancellation method and compute the Hawking fluxes in those two metrics. Our Hawking fluxes involve three effects: (1) quantum gravity effect regularizing the core of the black holes, (2) rotation of the black hole, (3) time-delay. Further in this paper toward the metric in which the dimensional could not be performed, we argue that it would be some problematic metric, and mention its cause. The Hawking fluxes we compute in this study could be considered to correspond to more realistic Hawking fluxes. Further what Hawking fluxes can be obtained from the anomaly cancellation method would be interesting in terms of the relation between a consistency of quantum field theories and black hole thermodynamics.

  18. Nesting ecology and behavior of Broad-winged Hawks in moist karst forests of Puerto Rico

    Science.gov (United States)

    Hengstenberg, D.W.; Vilella, F.J.

    2005-01-01

    The Puerto Rican Broad-winged Hawk (Buteo platypterus brunnescens) is an endemic and endangered subspecies inhabiting upland montane forests of Puerto Rico. The reproductive ecology, behavior, and nesting habitat of the Broad-winged Hawk were studied in Ri??o Abajo Forest, Puerto Rico, from 2001-02. We observed 158 courtship displays by Broad-winged Hawks. Also, we recorded 25 territorial interactions between resident Broad-winged Hawks and intruding Red-tailed Hawks (Buteo jamaicensis jamaicensis). Broad-winged Hawks displaced intruding Red-tailed Hawks from occupied territories (P = 0.009). Mayfield nest survival was 0.67 across breeding seasons (0.81 in 2001, N = 6; 0.51 in 2002, N = 4), and pairs averaged 1.1 young per nest (years combined). The birds nested in mixed species timber plantations and mature secondary forest. Nests were placed in the upper reaches of large trees emerging from the canopy. Nest tree DBH, understory stem density, and distance to karst cliff wall correctly classified (77.8%) nest sites. ?? 2005 The Raptor Research Foundation, Inc.

  19. Backreaction of Hawking radiation on a gravitationally collapsing star I: Black holes?

    Directory of Open Access Journals (Sweden)

    Laura Mersini-Houghton

    2014-11-01

    Full Text Available Particle creation leading to Hawking radiation is produced by the changing gravitational field of the collapsing star. The two main initial conditions in the far past placed on the quantum field from which particles arise, are the Hartle–Hawking vacuum and the Unruh vacuum. The former leads to a time-symmetric thermal bath of radiation, while the latter to a flux of radiation coming out of the collapsing star. The energy of Hawking radiation in the interior of the collapsing star is negative and equal in magnitude to its value at future infinity. This work investigates the backreaction of Hawking radiation on the interior of a gravitationally collapsing star, in a Hartle–Hawking initial vacuum. It shows that due to the negative energy Hawking radiation in the interior, the collapse of the star stops at a finite radius, before the singularity and the event horizon of a black hole have a chance to form. That is, the star bounces instead of collapsing to a black hole. A trapped surface near the last stage of the star's collapse to its minimum size may still exist temporarily. Its formation depends on the details of collapse. Results for the case of Hawking flux of radiation with the Unruh initial state, will be given in a companion paper II.

  20. Effects of kinesio tape compared with non-elastic tape on hand grip strength.

    Science.gov (United States)

    Kim, Ji Young; Kim, Seong Yeol

    2016-05-01

    [Purpose] Many assumptions have been made about taping and several studies have considered tape application methods; however, the true effect of taping on muscle strength remains unclear. Most previous studies compared application techniques using Kinesio tape (KT), but studies that compared muscle strength using non-elastic tape (NT) are limited. Moreover, no studies have applied KT and NT in the same way to assess grip strength in normal subjects. The purpose of this study was to evaluate the immediate effect of application of two tapes with different elastic properties on maximal grip strength in healthy adults. [Subjects and Methods] Twenty healthy adults were divided into two groups (KT and NT). Maximal grip strength was measured with a dynamometer. Forearm extensor muscles of the dominant hand were then taped and subjects were immediately asked to perform hand grip movement with maximum strength in the same standardized manner. [Results] In the KT group, maximal grip strength was significantly increased compared to the initial value; however, in the NT group, there was no significant difference in maximal grip strength. [Conclusion] This study suggests that only Kinesio tape can increase maximal grip strength immediately after application on the extensor region of the forearm.

  1. Using Hand Grip Force as a Correlate of Longitudinal Acceleration Comfort for Rapid Transit Trains.

    Science.gov (United States)

    Guo, Beiyuan; Gan, Weide; Fang, Weining

    2015-07-02

    Longitudinal acceleration comfort is one of the essential metrics used to evaluate the ride comfort of train. The aim of this study was to investigate the effectiveness of using hand grip force as a correlate of longitudinal acceleration comfort of rapid transit trains. In the paper, a motion simulation system was set up and a two-stage experiment was designed to investigate the role of the grip force on the longitudinal comfort of rapid transit trains. The results of the experiment show that the incremental grip force was linearly correlated with the longitudinal acceleration value, while the incremental grip force had no correlation with the direction of the longitudinal acceleration vector. The results also show that the effects of incremental grip force and acceleration duration on the longitudinal comfort of rapid transit trains were significant. Based on multiple regression analysis, a step function model was established to predict the longitudinal comfort of rapid transit trains using the incremental grip force and the acceleration duration. The feasibility and practicably of the model was verified by a field test. Furthermore, a comparative analysis shows that the motion simulation system and the grip force based model were valid to support the laboratory studies on the longitudinal comfort of rapid transit trains.

  2. Effects of kinesio tape compared with non-elastic tape on hand grip strength

    Science.gov (United States)

    Kim, Ji Young; Kim, Seong Yeol

    2016-01-01

    [Purpose] Many assumptions have been made about taping and several studies have considered tape application methods; however, the true effect of taping on muscle strength remains unclear. Most previous studies compared application techniques using Kinesio tape (KT), but studies that compared muscle strength using non-elastic tape (NT) are limited. Moreover, no studies have applied KT and NT in the same way to assess grip strength in normal subjects. The purpose of this study was to evaluate the immediate effect of application of two tapes with different elastic properties on maximal grip strength in healthy adults. [Subjects and Methods] Twenty healthy adults were divided into two groups (KT and NT). Maximal grip strength was measured with a dynamometer. Forearm extensor muscles of the dominant hand were then taped and subjects were immediately asked to perform hand grip movement with maximum strength in the same standardized manner. [Results] In the KT group, maximal grip strength was significantly increased compared to the initial value; however, in the NT group, there was no significant difference in maximal grip strength. [Conclusion] This study suggests that only Kinesio tape can increase maximal grip strength immediately after application on the extensor region of the forearm. PMID:27313372

  3. Covariant anomalies and Hawking radiation from Kaluza–Klein AdS black holes

    Indian Academy of Sciences (India)

    Chuan-Yi Bai

    2013-02-01

    In this paper, Hawking radiation is studied from four-dimensional (4D) Kaluza–Klein (KK) AdS black holes via the method of anomaly cancellation. The {|bf KK-AdS} black hole considered is a non-extremal charged rotating solution in the theory of 4D gauged supergravity. Its Hawking fluxes of electric charge, angular momentum and energy momentum tensor are derived here. Our results support the common view that Hawking radiation is the quantum effect arising at the event horizon.

  4. Hawking radiation of Schwarzschild-de Sitter black hole by Hamilton-Jacobi method

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, M. Atiqur, E-mail: atirubd@yahoo.com [Department of Applied Mathematics, Rajshahi University (Bangladesh); Hossain, M. Ilias, E-mail: ilias_math@yahoo.com [Department of Mathematics, Rajshahi University, Rajshahi, 6205 (Bangladesh)

    2012-05-30

    We investigate the Hawking radiation of Schwarzschild-de Sitter (SdS) black hole by massive particles tunneling method. We consider the spacetime background to be dynamical, incorporate the self-gravitation effect of the emitted particles and show that the tunneling rate is related to the change of Bekenstein-Hawking entropy and the derived emission spectrum deviates from the pure thermal spectrum when energy and angular momentum are conserved. Our result is also in accordance with Parikh and Wilczek's opinion and gives a correction to the Hawking radiation of SdS black hole.

  5. Hawking radiation of Kerr-de Sitter black holes using Hamilton-Jacobi method

    Science.gov (United States)

    Ibungochouba Singh, T.; Ablu Meitei, I.; Yugindro Singh, K.

    2013-05-01

    Hawking radiation of Kerr-de Sitter black hole is investigated using Hamilton-Jacobi method. When the well-behaved Painleve coordinate system and Eddington coordinate are used, we get the correct result of Bekenstein-Hawking entropy before and after radiation but a direct computation will lead to a wrong result via Hamilton-Jacobi method. Our results show that the tunneling probability is related to the change of Bekenstein-Hawking entropy and the derived emission spectrum deviates from the pure thermal but it is consistent with underlying unitary theory.

  6. Hawking radiation of Schwarzschild-de Sitter black hole by Hamilton-Jacobi method

    Science.gov (United States)

    Rahman, M. Atiqur; Hossain, M. Ilias

    2012-05-01

    We investigate the Hawking radiation of Schwarzschild-de Sitter (SdS) black hole by massive particles tunneling method. We consider the spacetime background to be dynamical, incorporate the self-gravitation effect of the emitted particles and show that the tunneling rate is related to the change of Bekenstein-Hawking entropy and the derived emission spectrum deviates from the pure thermal spectrum when energy and angular momentum are conserved. Our result is also in accordance with Parikh and Wilczek's opinion and gives a correction to the Hawking radiation of SdS black hole.

  7. Hawking Radiation of Schwarzschild-de Sitter Black Hole by Hamilton-Jacobi method

    CERN Document Server

    Rahman, M Atiqur; 10.1016/j.physletb.2012.04.049

    2012-01-01

    We investigate the Hawking radiation of Schwarzschild-de Sitter (SdS) black hole by massive particles tunneling method. We consider the spacetime background to be dynamical, incorporate the self-gravitation effect of the emitted particles and show that the tunneling rate is related to the change of Bekenstein-Hawking entropy and the derived emission spectrum deviates from the pure thermal spectrum when energy and angular momentum are conserved. Our result is also in accordance with Parikh and Wilczek\\rq s opinion and gives a correction to the Hawking radiation of SdS black hole.

  8. Kinetic measurements of hand motor impairments after mild to moderate stroke using grip control tasks.

    Science.gov (United States)

    Ye, Yu; Ma, Le; Yan, Tiebin; Liu, Huihua; Wei, Xijun; Song, Rong

    2014-05-11

    The aim of this study is to investigate quantitative outcome measurements of hand motor performance for subjects after mild to moderate stroke using grip control tasks and characterize abnormal flexion synergy of upper extremities after stroke. A customized dynamometer with force sensors was used to measure grip force and calculate rotation torque during the sub-maximal grip control tasks. The paretic and nonpartic sides of eleven subjects after stroke and the dominant sides of ten healthy persons were tested. Their maximal voluntary grip force was measured and used to set sub-maximal grip control tasks at three different target force levels. Force control ability was characterized by the maximal grip force, mean force percentage, coefficient of variation (CV), target deviation ratio (TDR), and rotation torque ratio (RTR). The motor impairments of subjects after stroke were also evaluated using the Fugl-Meyer assessment for upper extremity (FMA-UE) and Wolf Motor Function Test (WMFT). Maximal grip force of the paretic side was significantly reduced as compared to the nonparetic side and the healthy group, while the difference of maximal grip force between the nonparetic side and the healthy group was not significant. TDR and RTR increased for all three groups with increasing target force level. There were significant differences of CV, TDR and RTR between the paretic side and the healthy group at all the force levels. CV, TDR and RTR showed significant negative correlations with FMA-UE and WMFT at 50% of maximum grip force. This study designed a customized dynamometer together with an innovative measurement, RTR, to investigate the hand motor performance of subjects after mild to moderate stroke during force control tasks. And stroke-induced abnormal flexion synergy of wrist and finger muscles could be characterized by RTR. This study also identified a set of kinetic parameters which can be applied to quantitatively assess the hand motor function of subjects after

  9. Hand-grip strength cut points to screen older persons at risk for mobility limitation.

    Science.gov (United States)

    Sallinen, Janne; Stenholm, Sari; Rantanen, Taina; Heliövaara, Markku; Sainio, Päivi; Koskinen, Seppo

    2010-09-01

    To determine optimal hand-grip strength cut points for likelihood of mobility limitation in older people and to study whether these cut points differ according to body mass index (BMI). Cross-sectional analysis of data. Data collected in the Finnish population-based Health 2000 Survey. One thousand eighty-four men and 1,562 women aged 55 and older with complete data on anthropometry, hand-grip strength and self-reported mobility. Mobility limitation was defined as difficulty walking 0.5 km or climbing stairs. Receiver operating characteristic analysis was used to estimate hand-grip strength cut points for likelihood of mobility limitation. The overall hand-grip strength cut points for likelihood of mobility limitation were 37 kg (sensitivity 62%; specificity 76%) for men and 21 kg (sensitivity 67%; specificity 73%) for women. The effect of the interaction between hand-grip strength and BMI on mobility limitation was significant in men (P=.02), but no such interaction was observed in women (P=.16). In men, the most-optimal cutoff points were 33 kg (sensitivity 73%; specificity 79%) for normal-weight men, 39 kg (sensitivity 67%; specificity 71%) for overweight men, and 40 kg (sensitivity 57%; specificity 68%) for obese men. In women, BMI-specific hand-grip strength cutoff values was not markedly more accurate than the overall cutoff value. The hand-grip strength test is a useful tool to identify persons at risk of mobility limitation. In men, hand-grip strength cut points for mobility increased with BMI, whereas in women, only one hand-grip strength threshold was identified. © 2010, Copyright the Authors. Journal compilation © 2010, The American Geriatrics Society.

  10. Temporary threshold shift of vibratory sensation induced by a vibrating handle and its gripping force.

    Science.gov (United States)

    Nishiyama, K; Taoda, K; Yamashita, H; Watanabe, S

    1996-01-01

    This study examines the effect of the force with which a vibrating handle is gripped on the temporary threshold shift of vibratory sensation (TTSv) induced by hand-arm vibration. Six healthy subjects gripped a handle vibrating with a 1.3 octave-band vibration, with a central frequency of 200 Hz and an intensity of 39.2 m/s2. Exposure was for 1 min and 10 min, respectively. Gripping forces for the 1-min exposure were 5 N, 10 N, 40 N and 80 N, respectively, with 0 N push-pull force. Gripping forces for the 10-min exposure were the same as for the 1-min exposure but omitting 80 N. The vibratory sensation threshold at 125 Hz was measured before and after exposure of an exposed fingertip to vibration. The differences measured determine TTSv.t at time t. TTSv.t determines TTSv.0, that is, the temporary threshold shift of vibratory sensation immediately after exposure to vibration according to the estimate made on the basis of the preceding study. The same experimental conditions were repeated 3 times on different days in a soundproof and thermoregulated room. Our findings show that TTSv increases significantly with increasing gripping force. We also determined the quantitative relationships between TTSv.0 and gripping force as described by the equation TTSv.0 = exp(kf x F + Cf). where kt and Cf are constants and F is gripping force. This study revealed the importance of ergonomic design in reducing the force with which a vibrating handle is gripped to prevent an adverse effect of local vibration. The equation devised may help in the quantitative assessment of the effect of reduced gripping force.

  11. Immediate and Delayed Effects of Forearm Kinesio Taping on Grip Strength

    Science.gov (United States)

    Kouhzad Mohammadi, Hosein; Khademi Kalantari, Khosro; Naeimi, Sedighe Sadat; Pouretezad, Mohammad; Shokri, Esmaeil; Tafazoli, Mojdeh; Dastjerdi, Mahboobeh; Kardooni, Leila

    2014-01-01

    Background: Due to the fundamental role of gripping in most upper limb activities, grip strength promotion is a chief goal in the treatment of patients with upper limb musculoskeletal disorders. Kinesio taping is a novel and effective therapeutic technique believed to facilitate muscle contraction through stimulating mechanoreceptors and increasing the sensory feedback around the taped region. Objectives: The present study aimed to identify the best region (flexor, extensor and flexor/extensor regions) and time (immediate, 0.5, 1, 1.5, and 2 hours) of forearm Kinesio taping to obtain the maximum improvement in grip strength. Materials and Methods: In this longitudinal study, 40 healthy men and women (the mean age of 22.3 ± 2.19 years) were selected among students of Shahid Beheshti University of Medical Sciences, Tehran, Iran by simple, nonrandom sampling method. A dynamometer was used to measure grip strength immediately and every 30 minutes during the two hours after I-shaped application of tape (with 50% stretch) to the flexor, extensor, and flexor/extensor forearm muscles. Results: Grip strength was significantly increased in various muscle groups for males (P = 0.002) and females (P = 0.000) of the forearm and at different intervals for males (P = 0.000) and females (P = 0.000). Moreover, in both men and women, tape application to the extensor region provided greater grip strength compared to taping of the flexor and flexor/extensor regions (P = 0.000 for both). Furthermore, the maximum increase in grip strength were 0.5 (10.8% increase, P = 0.001) and 1.5 h (23.9% increase, P = 0.000) after taping in males and females, respectively. Conclusions: Taping the extensor region of forearm is recommended to achieve higher grip strength. Although grip strength increased at a slower pace in females than males, the final values were higher in women. PMID:25389492

  12. The imprint of the Hawking effect in subcritical flows

    CERN Document Server

    Coutant, Antonin

    2016-01-01

    We study the propagation of low frequency shallow water waves on a one dimensional flow of varying depth. When taking into account dispersive effects, the linear propagation of long wavelength modes on uneven bottoms excites new solutions of the dispersion relation which possess a much shorter wavelength. The peculiarity is that one of these new solutions has a negative energy. When the flow becomes supercritical, this mode has been shown to be responsible for the (classical) analog of the Hawking effect. For subcritical flows, the production of this mode has been observed numerically and experimentally, but the precise physics governing the scattering remained unclear. In this work, we provide an analytic treatment of this effect in subcritical flows. We analyze the scattering of low frequency waves using a new perturbative series, derived from a generalization of the Bremmer series. We show that the production of short wavelength modes is governed by a complex value of the position: a complex turning point....

  13. Tunneling method for Hawking radiation in the Nariai case

    CERN Document Server

    Belgiorno, F; Piazza, F Dalla

    2016-01-01

    Particle creation associated with the Hawking effect is calculated in the case of the charged Nariai solution, for the case both of the event horizon and of the cosmological horizon. We apply the Hamilton-Jacobi formalism, and, after a revisitation in the framework of particle creation in external fields {\\sl \\`a la} Nikishov, we consider in particular the case of a charged scalar field on the given background. Due to the knowledge of the exact solutions for the Klein-Gordon equations on Nariai manifold, and to their analytic properties on the extended manifold, we can corroborate the tunneling picture also by means of a direct computation of the flux of particles leaving the horizon.

  14. A silence black hole: Hawking radiation at the Hagedorn temperature

    CERN Document Server

    Lorente-Espin, O

    2008-01-01

    We compute semi-classically the Hawking emission for different types of black hole in type II string theory. In particular we analyze the thermal transition between NS5 branes and Little String Theory, finding compelling evidence for information recovering. We find that once the near horizon limit is taken the emission of a full family of models is exactly thermal even if back-reaction is taken into account. Consequently these theories are non-unitary and can not convey any information about the black hole internal states. It is argue that this behaviour matches the string theory expectations. We suggest a plausible reason for the vanishing of the jet-quenching parameter in such theories.

  15. Hawking Radiation from the Horowitz-Strominger Black Hole

    Institute of Scientific and Technical Information of China (English)

    FANG Heng-Zhong; HU Ya-Peng; ZHAO Zheng

    2005-01-01

    @@ When a black hole radiates particles, it losses energy and shrinks, the horizon contracts from its original radius to a new smaller radius. This leads to the separation between the initial and finalradii, which sets the barrier for the particles to tunnel. We develop the work of Parikh [Phys. Rev. Lett. 85 (2000) 5042; Gen. Rel. Gray.36 (2004) 2419] to a Horowitz-Strominger black hole, i.e. applying the Wentzel-Kramers-Brillouin approximation and semi-classical method to calculate the rate of the Hawking radiation. The result agrees with Γ~ e-2ImI =e△SBH. It is also proven that the energy spectrum deviates from exact thermality.

  16. The Hawking effect in dielectric media and the Hopfield model

    CERN Document Server

    Belgiorno, F; Piazza, F Dalla

    2014-01-01

    We consider the so-called Hopfield model for the electromagnetic field in a dielectric dispersive medium in a framework in which one allows a space-time dependence of microscopic parameters, aimed to a phenomenological description of a space-time varying dielectric perturbation induced by means of the Kerr effect. We discuss the analogue Hawking effect, by first analyzing the geometrical optics for the Hopfield model, and then by introducing a simplified model which has the bonus to avoid many difficulties which are involved in the full Hopfield model, still keeping the same dispersion relation. Amplitude calculations are indicated, and generalized Manley-Rowe identities are derived in a quantum scattering theory framework. Our main result is an analytical calculation of the spontaneous thermal emission in the single-branch case, which is provided non perturbatively for the first time in the framework of dielectric black holes. An universal mechanism for thermality between optical black holes and acoustic bla...

  17. Dark Spinors Hawking Radiation in String Theory Black Holes

    Directory of Open Access Journals (Sweden)

    R. T. Cavalcanti

    2016-01-01

    Full Text Available The Hawking radiation spectrum of Kerr-Sen axion-dilaton black holes is derived, in the context of dark spinors tunnelling across the horizon. Since a black hole has a well defined temperature, it should radiate in principle all the standard model particles, similar to a black body at that temperature. We investigate the tunnelling of mass dimension one spin-1/2 dark fermions, which are beyond the standard model and are prime candidates to the dark matter. Their interactions with the standard model matter and gauge fields are suppressed by at least one power of unification scale, being restricted just to the Higgs field and to the graviton likewise. The tunnelling method for the emission and absorption of mass dimension one particles across the event horizon of Kerr-Sen axion-dilaton black holes is shown here to provide further evidence for the universality of black hole radiation, further encompassing particles beyond the standard model.

  18. Is the Hawking Quasilocal Energy “Newtonian”?

    Directory of Open Access Journals (Sweden)

    Valerio Faraoni

    2015-11-01

    Full Text Available The Misner–Sharp–Hernandez mass defined in general relativity and in spherical symmetry has been recognized as having a Newtonian character in previous literature. In order to better understand this feature we relax spherical symmetry and we study the generalization of the Misner–Sharp–Hernandez mass to general spacetimes, i.e., the Hawking quasilocal mass. The latter is decomposed into a matter contribution and a contribution coming solely from the Weyl tensor. The Weyl tensor is then decomposed into an electric part (which has a Newtonian counterpart and a magnetic one (which does not, which further splits the quasilocal mass into “Newtonian” and “non-Newtonian” parts. Only the electric (Newtonian part contributes to the quasilocal mass.

  19. Chlamydiosis in a red-tailed hawk (Buteo jamaicensis).

    Science.gov (United States)

    Mirandé, L A; Howerth, E W; Poston, R P

    1992-04-01

    A red-tailed hawk (Buteo jamaicensis) with signs of respiratory distress and diarrhea was captured in the Manchac Wildlife Management Area, Louisiana (USA) and died the following day. At necropsy, the carcass was emaciated and there were splenomegaly, and fibrinous pericarditis, airsacculitis, and perihepatitis. Microscopically, there were fibrinous pericarditis and airsacculitis, myocardial necrosis, necrotizing hepatitis, splenic necrosis with reticuloendothelial cell hyperplasia, interstitial pneumonia and focal pancreatic necrosis. Intracytoplasmic chlamydial inclusion bodies were noticed in macrophages in the fibrinous exudate covering air sac and pericardium, and in spleen, liver, heart, lung, and pancreas. Schizonts compatible with a Sarcocystis sp.-like protozoon were present in the walls of air capillaries in the lung. A Chlamydia sp.-like organism was isolated in embryonating chicken eggs and cell culture and identified as C. psittaci with immunofluorescent staining.

  20. Modified Bekenstein-Hawking system in $f(R)$ gravity

    CERN Document Server

    Dutta, Jibitesh; Chetry, Binod

    2016-01-01

    The present work deals with four alternative formulation of Bekenstein system on event horizon in $f(R)$ gravity. While thermodynamical laws holds in universe bounded by apparent horizon, these laws break down on event horizon. With alternative formulation of thermodynamical parameters (temperature and entropy), thermodynamical laws hold on event horizon in Einstein Gravity. With this motivation, we extend the idea of generalised Hawking temperature and modified Bekenstein entropy in homogeneous and isotropic model of universe on event horizon and examine whether thermodynamical laws hold in f(R) gravity. Specifically, we examine and compare validity of generalised second law of thermodynamics (GSLT) and thermodynamical equilibrium (TE) in four alternative modified Bekenstein scenarios. As Dark energy is a possible dominant candidate for matter in the univerese and Holographic Dark Energy (HDE) can give effective description of f(R) gravity, so matter in the universe is taken as in the form interacting HDE. I...

  1. Comprehensive study of endurance for IAR-99 Hawk

    Directory of Open Access Journals (Sweden)

    Dorin LOZICI-BRINZEI

    2014-03-01

    Full Text Available The paper presents some methods of on-ground and in-flight calibration for strain gauges, intended to the development of complex programs which analyze the endurance phenomena for aerospace structures, with direct application to the IAR-99 Hawk. The strain gauges have the advantage of being sensitive to load and therefore to aerodynamic phenomena, thereby providing indications of the loads supported by the structure. The effects size of loads type phenomena caused by wind gusts or buffet can be measured only by strain gauges or accelerometres70 and they cannot be recorded by flight or fatigue parameters counters. The installation of a strain gauge is made using a pattern (its position and orientation are crucial and the strain gauge selected for installation should not be fragile or unstable. Routines should be established for periodic inspection of strain gauges and those which are defective should be replaced immediately.

  2. Extraction, purification and characterization of polysaccharides from Hawk tea.

    Science.gov (United States)

    Jia, Xuejing; Ding, Chunbang; Yuan, Shu; Zhang, Zhongwei; Chen, Yang'er; Du, Lei; Yuan, Ming

    2014-01-01

    In the present study, the extraction, purification and characterization of polysaccharides from Hawk mature leaf tea (HMP) were investigated. The optimal extraction parameters were obtained by using a Box-Behnken design as follows: extraction temperature 88.9 °C, extraction time 128.2 min and ratio of water to solid 11.4 mL/g. The crude HMP was sequentially purified by chromatography of DEAE-52, and two purified fractions, HMP-1 and HMP-2, were obtained. HMP-1 and HMP-2 were mainly composed of arabinose, galactose, glucose and mannose with the molecular weight of 133 and 100 kDa, respectively. For antioxidant activities in vitro, HMP-1 had strong 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity and ferric reducing activity power (FRAP). These results provide a scientific basis for the further use of polysaccharides from this traditional herb tea. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Towards a Hartle-Hawking state for loop quantum gravity

    CERN Document Server

    Dhandhukiya, Satya

    2016-01-01

    The Hartle-Hawking state is a proposal for a preferred initial state for quantum gravity, based on a path integral over all compact Euclidean four-geometries which have a given three-geometry as a boundary. The wave function constructed this way satisfies the (Lorentzian) Hamiltonian constraint of general relativity in ADM variables in a formal sense. In this article we mimic this procedure of constructing an initial state in terms of Ashtekar-Barbero variables, and observe that the wave function thus constructed does not satisfy the Lorentzian Hamiltonian constraint even in a formal sense. We also investigate this issue for the relativistic particle. We finally suggest a modification of the proposal that does satisfy the constraint at least in a formal sense and start to consider its implications in quantum cosmology.

  4. Correlations in Hawking radiation and the infall problem

    CERN Document Server

    Mathur, Samir D

    2011-01-01

    It is sometimes believed that small quantum gravity effects can encode information as `delicate correlations' in Hawking radiation, thus saving unitarity while maintaining a semiclassical horizon. A recently derived inequality showed that this belief is incorrect: one must have order unity corrections to low energy evolution at the horizon (i.e. fuzzballs) to remove entanglement between radiation and the hole. In this paper we take several models of `small corrections' and compute the entanglement entropy numerically; in each case this entanglement is seen to monotonically grow, in agreement with the general inequality. We also construct a model of `burning paper', where the entanglement is found to rise and then return to zero, in agreement with the general arguments of Page. We then note that the fuzzball structure of string microstates offers a version of `complementarity'. Low energy evolution is modified by order unity, resolving the information problem, while for high energy infalling modes ($E>> kT$) w...

  5. Hawking Radiation and Nonequilibrium Quantum Critical Current Noise

    Science.gov (United States)

    Sonner, Julian; Green, A. G.

    2012-08-01

    The dynamical scaling of quantum critical systems in thermal equilibrium may be inherited in the driven steady state, leading to universal out-of-equilibrium behavior. This attractive notion has been demonstrated in just a few cases. We demonstrate how holography—a mapping between the quantum critical system and a gravity dual—provides an illuminating perspective and new results. Nontrivial out-of-equilibrium universality is particularly apparent in current noise, which is dual to Hawking radiation in the gravitational system. We calculate this in a two-dimensional system driven by a strong in-plane electric field and deduce a universal scaling function interpolating between previously established equilibrium and far-from-equilibrium current noise. Since this applies at all fields, out-of-equilibrium experiments no longer require very high fields for comparison with theory.

  6. Anticipatory grip force between 1 and 3g

    Science.gov (United States)

    White, Olivier; Van Loon, ing.. Jack J. W. A.; Thonnard, Jean-Louis; Hermsdorfer, Joachim; Lefevre, Philippe

    One remarkable capacity of utilizing common tools appropriately as soon as we grasp them relies on the ability to determine in advance the grip force (GF) required to handle them in relation to their mechanical properties and the surrounding environment. This anticipatory strategy avoids the uncompressible delays in the feedback system. The predictive control of GF is made possible because the nervous system can learn, store and then select the internal representations of the dynamics of innumerable objects, known as internal models. Beside this flexibility, the nervous system's ability to learn different task dynamics is often limited in classical robotic experiments The environment itself can be profoundly modified in altered gravity or centrifugation. The few studies that investigated motor adaptation in such contexts did not consider the interaction between gravitational phases and even less the transitions across environments. Here, we tested subject's abilities to adapt to levels of gravitational fields generated by a human centrifuge. In Experiment 1, seven subjects performed 4 lifting trials in each gravitational phase (1 to 2.5g and then 2.5 to 1g by steps of 0.5g) with a 0.12 kg instrumented object. In Experiment 2, six subjects performed vertical oscillations of the object during transitions between 1 and 3g (0.5g steps, ascending and descending phases, profile repeated twice). We continuously measured GF, load force (LF) and ambient gravity. We hypothesized that participants were able to predictively adjust GF to the new environment. In Experiment 1, participants adjusted their GF proportionally to gravity and decreased GF across trials within a given gravitational environment. Preload phases decreased over time from 300ms to 50ms irrespective of gravity. We quantified the abilities of participants to switch across environments by subtracting GF recorded in the last trial in the current gravity level from GF during the first trial in the new environment

  7. High prevalence of Sarcocystis calchasi sporocysts in European Accipiter hawks.

    Science.gov (United States)

    Olias, Philipp; Olias, Lena; Krücken, Jürgen; Lierz, Michael; Gruber, Achim D

    2011-02-10

    The emerging Sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (Columba livia f. domestica). Experimental studies have identified the Northern goshawk (Accipiter g. gentilis) as final host. Phylogenetically closely related European sparrowhawks (Accipiter n. nisus) and wood pigeons (Columba palumbus) have been found to harbor genetically closely related Sarcocystis spp. However, data on the prevalence and potential interspecies occurrence of these parasites are lacking. Here, we report that European Accipiter hawks (Accipitrinae) are highly infected with S. calchasi, S. columbae and Sarcocystis sp. ex A. nisus in their small intestine. Thirty-one of 50 (62%) Northern goshawks necropsied during 1997-2008 were positive for S. calchasi in a newly established species-specific semi-nested PCR assay based on the first internal transcribed spacer region. Unexpectedly, 14 of 20 (71.4%) European sparrowhawks tested also positive. In addition, birds of both species were found to be infested with S. columbae and an, as yet, unnamed Sarcocystis sp. recently isolated from European sparrowhawks. These findings raise new questions about the host specificity of S. calchasi and its high virulence in domestic pigeons, since sparrowhawks only rarely prey on pigeons. Notably, isolated sporocysts from both infected Accipiter spp. measured 8 μm × 11.9 μm, precluding a preliminary identification of S. calchasi in feces of Accipiter hawks based on morphology alone. Importantly, three of four Northern goshawks used in falconry tested positive for S. calchasi. In conclusion, the results indicate that both European Accipter spp. in Germany serve as natural final hosts of S. calchasi and suggest that falconry and pigeon sport may serve as risk factors for the spread of this pathogen in domestic pigeons.

  8. Christopher Hawkes and the International Summer Courses of Ampurias

    Directory of Open Access Journals (Sweden)

    Margarita Díaz-Andreu

    2007-05-01

    Full Text Available This article aims to provide an initial analysis of the early connections between Christopher Hawkes and Spanish archaeology in the context of his participation in two of the international summer courses in Ampurias in 1947 and 1950. The documentation used for this article comes mainly from the Pericot Archive in the Library of Catalonia, in which there are 43 letters from Hawkes to Pericot between 1940 and 1975. In addition, other correspondence in the British Museum and in the Ministry of Foreign Affairs will be mentioned. This study forms part of a larger project of recovering the memory of twentieth-century British-Spanish relations, of which a first phase has centred on the assessment of Gordon Childe’s contacts with Spain (Díaz-Andreu 1998; forthcoming–a; forthcoming–b. As in Gordon Childe’s case, all memory of Hawkes’ visits, and indeed of his relationships with Spanish archaeologists, has since been lost. Unfortunately, this situation is not exceptional: most of the links between Spanish archaeologists and British and American archaeologists in the twenty years around the Spanish Civil War have dropped out of archaeological memory. To the names mentioned in a recent seminar (Gordon Childe, Edward Thurlow Leeds, Eoin MacWhite, Hubert Savory (Armada Pita 2006, many others could be added. As this article will show, however, there were many contacts and these help to explain some developments in the archaeological thinking and practice of the participants involved in these exchanges, as well as some events in the international organisation of archaeology.

  9. Public perceptions of a rip current hazard education program: "Break the Grip of the Rip!"

    Science.gov (United States)

    Houser, Chris; Trimble, Sarah; Brander, Robert; Brewster, B. Chris; Dusek, Greg; Jones, Deborah; Kuhn, John

    2017-07-01

    Rip currents pose a major global beach hazard; estimates of annual rip-current-related deaths in the United States alone range from 35 to 100 per year. Despite increased social research into beach-goer experience, little is known about levels of rip current knowledge within the general population. This study describes the results of an online survey to determine the extent of rip current knowledge across the United States, with the aim of improving and enhancing existing beach safety education material. Results suggest that the US-based Break the Grip of the Rip!® campaign has been successful in educating the public about rip current safety directly or indirectly, with the majority of respondents able to provide an accurate description of how to escape a rip current. However, the success of the campaign is limited by discrepancies between personal observations at the beach and rip forecasts that are broadcasted for a large area and time. It was the infrequent beach user that identified the largest discrepancies between the forecast and their observations. Since infrequent beach users also do not seek out lifeguards or take the same precautions as frequent beach users, it is argued that they are also at greatest risk of being caught in a dangerous situation. Results of this study suggest a need for the national campaign to provide greater focus on locally specific and verified rip forecasts and signage in coordination with lifeguards, but not at the expense of the successful national awareness program.

  10. Hawkes-diffusion process and the conditional probability of defaults in the Eurozone

    Science.gov (United States)

    Kim, Jungmu; Park, Yuen Jung; Ryu, Doojin

    2016-05-01

    This study examines market information embedded in the European sovereign CDS (credit default swap) market by analyzing the sovereign CDSs of 13 Eurozone countries from January 1, 2008, to February 29, 2012, which includes the recent Eurozone debt crisis period. We design the conditional probability of defaults for the CDS prices based on the Hawkes-diffusion process and obtain the theoretical prices of CDS indexes. To estimate the model parameters, we calibrate the model prices to empirical prices obtained from individual sovereign CDS term structure data. The estimated parameters clearly explain both cross-sectional and time-series data. Our empirical results show that the probability of a huge loss event sharply increased during the Eurozone debt crisis, indicating a contagion effect. Even countries with strong and stable economies, such as Germany and France, suffered from the contagion effect. We also find that the probability of small events is sensitive to the state of the economy, spiking several times due to the global financial crisis and the Greek government debt crisis.

  11. Delivery of Unmanned Aerial Vehicle Data

    Science.gov (United States)

    Ivancic, William D.; Sullivan, Donald V.

    2011-01-01

    To support much of NASA's Upper Atmosphere Research Program science, NASA has acquired two Global Hawk Unmanned Aerial Vehicles (UAVs). Two major missions are currently planned using the Global Hawk: the Global Hawk Pacific (GloPac) and the Genesis and Rapid Intensification Processes (GRIP) missions. This paper briefly describes GloPac and GRIP, the concept of operations and the resulting requirements and communication architectures. Also discussed are requirements for future missions that may use satellite systems and networks owned and operated by third parties.

  12. Higgs v Hawking: a battle of the heavyweights that has shaken the world of theoretical physics

    CERN Multimedia

    Connor, S

    2002-01-01

    Stephen Hawking was accused yesterday of receiving instant credibility because of his celebrity status. His accuser was Professor Peter Higgs, who predicted the existence of the elementary particle, the Higgs Boson, in the 1960s (1 page).

  13. Information-carrying Hawking radiation and the number of microstate for a black hole

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Qing-yu, E-mail: qycai@wipm.ac.cn [State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Sun, Chang-pu, E-mail: cpsun@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100084 (China); Collaborative Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); You, Li, E-mail: lyou@mail.tsinghua.edu.cn [State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2016-04-15

    We present a necessary and sufficient condition to falsify whether a Hawking radiation spectrum indicates unitary emission process or not from the perspective of information theory. With this condition, we show the precise values of Bekenstein–Hawking entropies for Schwarzschild black holes and Reissner–Nordström black holes can be calculated by counting the microstates of their Hawking radiations. In particular, for the extremal Reissner–Nordström black hole, its number of microstate and the corresponding entropy we obtain are found to be consistent with the string theory results. Our finding helps to refute the dispute about the Bekenstein–Hawking entropy of extremal black holes in the semiclassical limit.

  14. Non-Riemannian effective spacetime effects on Hawking radiation in superfluids

    CERN Document Server

    Garcia de Andrade, L C

    2005-01-01

    Riemannian effective spacetime description of Hawking radiation in $^{3}He-A$ superfluids is extended to non-Riemannian effective spacetime. An example is given of non-Riemannian effective geometry of the rotational motion of the superfluid vacuum around the vortex where the effective spacetime Cartan torsion can be associated to the Hawking giving rise to a physical interpretation of effective torsion recently introduced in the literature in the form of an acoustic torsion in superfluid $^{4}He$ (PRD-70(2004),064004). Curvature and torsion singularities of this $^{3}He-A$ fermionic superfluid are investigated. This Lense-Thirring effective metric, representing the superfluid vacuum in rotational motion, is shown not support Hawking radiation when the isotropic $^{4}He$ is restored at far distances from the vortex axis. Hawking radiation can be expressed also in topological solitons (moving domain walls) in fermionic superfluids in non-Riemannian (teleparallel) $(1+1)$ dimensional effective spacetime. A telep...

  15. Information-carrying Hawking radiation and the number of microstate for a black hole

    Directory of Open Access Journals (Sweden)

    Qing-yu Cai

    2016-04-01

    Full Text Available We present a necessary and sufficient condition to falsify whether a Hawking radiation spectrum indicates unitary emission process or not from the perspective of information theory. With this condition, we show the precise values of Bekenstein–Hawking entropies for Schwarzschild black holes and Reissner–Nordström black holes can be calculated by counting the microstates of their Hawking radiations. In particular, for the extremal Reissner–Nordström black hole, its number of microstate and the corresponding entropy we obtain are found to be consistent with the string theory results. Our finding helps to refute the dispute about the Bekenstein–Hawking entropy of extremal black holes in the semiclassical limit.

  16. The GUP effect on Hawking radiation of the 2 + 1 dimensional black hole

    Science.gov (United States)

    Gecim, Ganim; Sucu, Yusuf

    2017-10-01

    We investigate the Generalized Uncertainty Principle (GUP) effect on the Hawking radiation of the 2 + 1 dimensional Martinez-Zanelli black hole by using the Hamilton-Jacobi method. In this connection, we discuss the tunneling probabilities and Hawking temperature of the spin-1/2 and spin-0 particles for the black hole. Therefore, we use the modified Klein-Gordon and Dirac equations based on the GUP. Then, we observe that the Hawking temperature of the scalar and Dirac particles depend on not only the black hole properties, but also the properties of the tunneling particle, such as angular momentum, energy and mass. And, in this situation, we see that the tunneling probability and the Hawking radiation of the Dirac particle is different from that of the scalar particle.

  17. No Information Is Lost: a Revisit of Hawking Radiation as Tunneling

    CERN Document Server

    Zhang, Baocheng; Zhan, Ming-sheng; You, Li

    2009-01-01

    We revisit in detail the paradox of black hole information loss due to Hawking radiation as tunneling. We compute the amount of information encoded in correlations among Hawking radiations for a variety of black holes, including the Schwarzchild black hole, the Reissner-Nordstr\\"{o}m black hole, the Kerr black hole, and the Kerr-Newman black hole. The special cases of tunneling through a quantum horizon and geometrically non-commutative black holes are also considered. Within a phenomenological treatment based on the accepted emission probability spectrum from a black hole, we find that information is leaked out hidden in the correlations of Hawking radiation. The recovery of this previously unaccounted for information helps to conserve the total entropy of a system composed of a black hole plus its radiations. We thus conclude, irrespective of the microscopic picture for black hole collapsing, the associated radiation process: Hawking radiation as tunneling, must be a unitary process.

  18. Colorado Plateau Rapid Ecoregion Assessment Conservation Elements - Terrestrial Species: Ferruginous Hawk

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — This map shows the potential current distribution of Ferruginous Hawk, in the context of current and near-term terrestrial intactness and long-term potential for...

  19. Proposal for Red-shouldered Hawk inventory and monitoring Mississippi River- Year 2000

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a proposal to conduct Red-shouldered Hawk inventory and monitoring research along the Mississippi River. Objectives of the proposed study include: (1)...

  20. Hawking radiation of Reissner-Nordstrom-de Sitter black hole by Hamilton-Jacobi method

    CERN Document Server

    Hossain, M Ilias

    2013-01-01

    In Refs. (M. Atiqur Rahman, M. Ilias Hossain (2012) Phys. Lett. B {\\bf 712} 1), we have developed Hamilton-Jacobi method for dynamical spacetime and discussed Hawking radiation of Schwarzschild-de Sitter black hole by massive particle tunneling method. In this letter, we have investigated the hawking purely thermal and nonthermal radiations of Reissner-Nordstr\\"{o}m-de Sitter (RNdS) black hole. We have considered energy and angular momentum as conserved and shown that the tunneling rate is related to the change of Bekenstein-Hawking entropy and the derived emission spectrum deviates from the pure thermal spectrum. The results we have obtained for RNdS black hole is also in accordance with Parikh and Wilczek\\rq s opinion and recovered the new result for Hawking radiation of RNdS black hole.

  1. Comparative Studies on Bioactive Constituents in Hawk Tea Infusions with Different Maturity Degree and Their Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Ming Yuan

    2014-01-01

    Full Text Available Hawk tea (Litsea coreana var. lanuginose is a very popular herbal tea in the southwest of China. According to the maturity degree of raw materials, Hawk tea can usually be divided into three types: Hawk bud tea (HB, Hawk primary leaf tea (HP, and Hawk mature leaf tea (HM. In this study, some of the bioactive constituents and antioxidant properties of the three kinds of Hawk tea infusions were comparatively investigated. The results showed that the contents of total flavonoids, vitamin C, and carbohydrates in Hawk bud tea infusion (HBI were higher than those in Hawk primary leaf tea infusion (HPI and Hawk mature leaf tea infusion (HMI. HPI had higher contents of total polyphenols and exhibited better DPPH radical scavenging activity and ferric reducing activity power. HBI could provide more effective protection against erythrocyte hemolysis. As age is going from bud to mature leaf, the ability to inhibit the formation of low density lipoprotein (LDL conjugated diene and the loss of tryptophan fluorescence decreased. The bioactive constituents and antioxidant activities of Hawk tea infusions were significantly affected by the maturity degree of the raw material.

  2. Pathologic findings in red-tailed hawks (Buteo jamaicensis) and Cooper's hawks (Accipiter cooper) naturally infected with West Nile virus.

    Science.gov (United States)

    Wünschmann, Arno; Shivers, Jan; Bender, Jeff; Carroll, Larry; Fuller, Susan; Saggese, Miguel; van Wettere, Arnaud; Redig, Pat

    2004-09-01

    Carcasses of 13 red-tailed hawks (RTHAs) and 11 Cooper's hawks (COHAs) were tested for West Nile virus (WNV) using WNV-specific reverse transcriptase-polymerase chain reaction (RT-PCR) on fresh brain tissue and WNV-specific immunohistochemistry (IHC) on various organs. Ten COHAs (91%) and 11 RTHAs (85%) were positive for WNV RNA by RT-PCR. All 11 COHAs (100%) and 10 RTHAs (77%) were positive for WNV antigen by IHC. A triad of inflammatory lesions, including chronic lymphoplasmacytic and histiocytic encephalitis, endophthalmitis, and myocarditis, was common in both species. In COHAs, the heart (54%), cerebrum (50%), and eye (45%) were the organs that most commonly contained WNV antigen. The amount of WNV antigen was usually small. In RTHAs, the kidney (38%), cerebrum (38%), cerebellum (38%), and eye (36%) were the organs most commonly containing WNV antigen. Unlike COHAs, larger amounts of WNV antigen were present in the cerebrum of RTHAs. WNV antigen was detected in similar cell populations in both species, including neurons of brain, spinal cord, and retina, pigmented epithelial cells of the retina, epithelial cells of renal medullary tubules, cardiomyocytes, endothelial cells and smooth muscle cells of arteries, dendritic cells of splenic lymph follicles, exocrine pancreatic cells, adrenal cells, and keratinocytes of the skin. The study presents strong evidence that WNV can cause a chronic fatal disease in RTHAs and COHAs. The lesion distribution of WNV infection in both species is variable, but inflammatory lesions are common, and a triad of lesions including encephalitis, myocarditis, and endophthalmitis is indicative of WNV infection in both species.

  3. Gripping during climbing of arboreal snakes may be safe but not economical

    Science.gov (United States)

    Byrnes, Greg; Jayne, Bruce C.

    2014-01-01

    On the steep surfaces that are common in arboreal environments, many types of animals without claws or adhesive structures must use muscular force to generate sufficient normal force to prevent slipping and climb successfully. Unlike many limbed arboreal animals that have discrete gripping regions on the feet, the elongate bodies of snakes allow for considerable modulation of both the size and orientation of the gripping region. We quantified the gripping forces of snakes climbing a vertical cylinder to determine the extent to which their force production favoured economy or safety. Our sample included four boid species and one colubrid. Nearly all of the gripping forces that we observed for each snake exceeded our estimate of the minimum required, and snakes commonly produced more than three times the normal force required to support their body weight. This suggests that a large safety factor to avoid slipping and falling is more important than locomotor economy. PMID:25142200

  4. lateral asymmetry ш grip strength: utility of the ten per cent rule

    African Journals Online (AJOL)

    2001-11-01

    Nov 1, 2001 ... between strengths of dominant and non-dominant hands. Such discrepancy in ... methodological approaches in evaluation of grip strength, different .... Relations between stronger hand and hand preference. Stronger hand.

  5. Spherically Symmetric Static Solution for a Schwarzschild Black Hole with Its Hawking Radiation

    Institute of Scientific and Technical Information of China (English)

    HUANG Chao-Guang

    2000-01-01

    A black hole and its Hawking radiation may be in stable thermal equilibrium. In this letter, the static spherically symmetric numerical solution for a Schwarzschild black hole with its Hawking radiation are obtained. In the calculation, the equilibrium system is supposed to consist of a black hole, thermal radiation and a two-dimensional surface layer. The solutions obtained are compared with the York's back-reaction approach and the Zhao-Liu thermodynamic approach.

  6. Hawking temperature of Kerr-Newman-AdS black hole from tunneling

    CERN Document Server

    Ma, Zheng Ze

    2009-01-01

    Using the null-geodesic tunneling method of Parikh and Wilczek, we derive the Hawking temperature of a general four-dimensional rotating black hole. In order to eliminate the motion of $\\phi$ degree of freedom of a tunneling particle, we have chosen a reference system that is co-rotating with the black hole horizon. Then we give the explicit result for the Hawking temperature of the Kerr-Newman-AdS black hole from the tunneling approach.

  7. MIGRATION PATTERNS, USE OF STOPOVER AREAS, AND AUSTRAL SUMMER MOVEMENTS OF SWAINSON'S HAWKS.

    Science.gov (United States)

    Kochert, Michael N; Fuller, Mark R; Schueck, Linda S; Bond, Laura; Bechard, Marc J; Woodbridge, Brian; Holroyd, Geoff; Martell, Mark; Banasch, Ursula

    From 1995-1998, we tracked movements of adult Swainson's Hawks (Buteo swainsoni) using satellite telemetry to characterize migration, important stopover areas, and austral summer movements. We tagged 46 hawks from July - September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson's Hawks basically followed three routes south on a broad front, converged along the east coast of central Mexico, and followed a concentrated corridor to a communal austral summer area in central Argentina. North of 20° N, southward and northward tracks differed little for individuals from east of the Continental Divide but differed greatly (up to 1700 km) for individuals from west of the Continental Divide. Hawks left the breeding grounds mid-August to mid-October; departure dates did not differ by location, year, or sex. South migration lasted 42 to 98 days, and north migration took 51 to 82 days. On south migration, 36% of the Swainson's Hawks departed the nesting grounds nearly 3 weeks earlier than the other radio marked hawks and made stopovers 9.0 - 26.0 days long in seven separate areas, mainly in the southern Great Plains, southern Arizona and New Mexico, and north-central Mexico. The austral period lasted 76 to 128 days. All Swainson's Hawks used a core area in central Argentina within 23% of the 738800 km(2) austral summer range where they frequently moved long distances (up to 1600 km). Conservation of Swainson's Hawks must be an international effort that considers habitats used during nesting and non-nesting seasons including migration stopovers.

  8. Hawking radiation of spin-1 particles from a three-dimensional rotating hairy black hole

    Energy Technology Data Exchange (ETDEWEB)

    Sakalli, I.; Ovgun, A., E-mail: ali.ovgun@emu.edu.tr [Eastern Mediterranean University Famagusta, North Cyprus, Department of Physics (Turkey)

    2015-09-15

    We study the Hawking radiation of spin-1 particles (so-called vector particles) from a three-dimensional rotating black hole with scalar hair using a Hamilton–Jacobi ansatz. Using the Proca equation in the WKB approximation, we obtain the tunneling spectrum of vector particles. We recover the standard Hawking temperature corresponding to the emission of these particles from a rotating black hole with scalar hair.

  9. Black hole and hawking radiation by type-II Weyl fermions

    Science.gov (United States)

    Volovik, G. E.

    2016-11-01

    The type-II Weyl and type-II Dirac fermions may emerge behind the event horizon of black holes. Correspondingly, the black hole can be simulated by creation of the region with overtilted Weyl or Dirac cones. The filling of the electronic states inside the "black hole" is accompanied by Hawking radiation. The Hawking temperature in the Weyl semimetals can reach the room temperature, if the black hole region is sufficiently small, and thus the effective gravity at the horizon is large.

  10. Hawking radiation from the dilaton-(anti) de Sitter black hole via covariant anomaly

    Institute of Scientific and Technical Information of China (English)

    Han Yi-Wen; Bao Zhi-Qing; Hong Yun

    2009-01-01

    Adopting the anomaly cancellation method, initiated by Robinson and Wilczek recently, this paper discusses Hawking radiation from the dilaton-(anti) de Sitter black hole. To save the underlying gauge and general covariance, it introduces covariant fluxes of gauge and energy-momentum tensor to cancel the gauge and gravitational anomalies. The result shows that the introduced compensating fluxes are equivalent to those of a 2-dimensional blackbody radiation at Hawking temperature with appropriate chemical potential.

  11. Hawking effect of Dirac particles in non-stationary Kerr space-time

    Institute of Scientific and Technical Information of China (English)

    黎忠恒; 赵峥

    1995-01-01

    In the process of dealing with the Hawking effect of Dirac particles in the non-stationary Kerr space-time, a new universal method to define the generalized Tortoise coordinate transformation is given. By means of this coordinate transformation, one can discuss the properties of the dynamical equation of particles near event horizons, and get automatically the temperature of Hawking radiation using the method suggested by Damour and others, and thereby dodge the difficulties in calculating the renormalised energy-momentum tensor.

  12. Hawking Radiation of Spin-1 Particles From Three Dimensional Rotating Hairy Black Hole

    CERN Document Server

    Sakalli, I

    2015-01-01

    In the present article, we study the Hawking radiation (HR) of spin-1 particles -- so-called vector particles -- from a three dimensional (3D) rotating black hole with scalar hair (RBHWSH) using Hamilton-Jacobi (HJ) ansatz. Putting the Proca equation amalgamated with the WKB approximation in process, the tunneling spectrum of vector particles is obtained. We recover the standard Hawking temperature corresponding to the emission of these particles from RBHWSH.

  13. Hawking Radiation of Vector Particles via Tunneling From 4-Dimensional And 5-Dimensional Black Holes

    CERN Document Server

    Feng, Zhongwen; Zu, Xiaotao

    2016-01-01

    Using Proca equation and WKB approximation, we investigate Hawking radiation of vector particles via tunneling from 4-dimensional Kerr-de Sitter black hole and 5-dimensional Schwarzschild-Tangherlini black hole. The results show that the tunneling rates and Hawking temperatures are depended on the properties of spacetime (event horizon, mass and angular momentum). Besides, our results are the same as scalars and fermions tunneling from 4-dimensional Kerr-de Sitter black hole and 5-dimensional Schwarzschild-Tangherlini black hole.

  14. Black hole and Hawking radiation by type-II Weyl fermions

    CERN Document Server

    Volovik, G E

    2016-01-01

    The type-II Weyl and type-II Dirac fermions may emerge behind the event horizon of black holes. Correspondingly the black hole can be simulated by creation of the region with overtilted Weyl or Dirac cones. The filling of the electronic states inside the "black hole" is accompanied by Hawking radiation. The Hawking temperature in the Weyl semimetals can reach the room temperature, if the black hole region is sufficiently small, and thus the effective gravity at the horizon is large.

  15. The Trilinear Hamiltonian: A Zero Dimensional Model of Hawking Radiation from a Quantized Source

    OpenAIRE

    Nation, P. D.; Blencowe, M. P.

    2010-01-01

    We investigate a quantum parametric amplifier with dynamical pump mode, viewed as a zero-dimensional model of Hawking radiation from an evaporating black hole. The conditions are derived under which the spectrum of particles generated from vacuum fluctuations deviates from the thermal spectrum predicted for the conventional parametric amplifier. We find that significant deviations arise when the pump mode (black hole) has emitted nearly half of its initial energy into the signal (Hawking radi...

  16. Analogue Hawking Radiation in a dc-SQUID Array Transmission Line

    Science.gov (United States)

    Nation, P. D.; Blencowe, M. P.; Rimberg, A. J.; Buks, E.

    2009-08-01

    We propose the use of a superconducting transmission line formed from an array of direct-current superconducting quantum interference devices for investigating analogue Hawking radiation. Biasing the array with a space-time varying flux modifies the propagation velocity of the transmission line, leading to an effective metric with a horizon. Being a fundamentally quantum mechanical device, this setup allows for investigations of quantum effects such as backreaction and analogue space-time fluctuations on the Hawking process.

  17. Effect of Putting Grip on Eye and Head Movements During the Golf Putting Stroke

    Directory of Open Access Journals (Sweden)

    George K. Hung

    2003-01-01

    Full Text Available The objective of this article is to determine the effect of three different putting grips (conventional, cross-hand, and one-handed on variations in eye and head movements during the putting stroke. Seven volunteer novice players, ranging in age from 21 to 22 years, participated in the study. During each experimental session, the subject stood on a specially designed platform covered with artificial turf and putted golf balls towards a standard golf hole. The three different types of grips were tested at two distances: 3 and 9 ft. For each condition, 20 putts were attempted. For each putt, data were recorded over a 3-s interval at a sampling rate of 100 Hz. Eye movements were recorded using a helmet-mounted eye movement monitor. Head rotation about an imaginary axis through the top of the head and its center-of-rotation was measured by means of a potentiometer mounted on a fixed frame and coupled to the helmet. Putter-head motion was measured using a linear array of infrared phototransistors embedded in the platform. The standard deviation (STD, relative to the initial level was calculated for eye and head movements over the duration of the putt (i.e., from the beginning of the backstroke, through the forward stroke, to impact. The averaged STD for the attempted putts was calculated for each subject. Then, the averaged STDs and other data for the seven subjects were statistically compared across the three grip conditions. The STD of eye movements were greater (p < 0.1 for conventional than cross-hand (9 ft and one-handed (3 and 9 ft grips. Also, the STD of head movements were greater (p < 0.1; 3 ft for conventional than cross-hand and one-handed grips. Vestibulo-ocular responses associated with head rotations could be observed in many 9 ft and some 3 ft putts. The duration of the putt was significantly longer (p < 0.05; 3 and 9 ft for the one-handed than conventional and cross-hand grips. Finally, performance, or percentage putts made, was

  18. Adaptive grip force is modulated by subthalamic beta activity in Parkinson's disease patients

    Directory of Open Access Journals (Sweden)

    Lukas L. Imbach

    2015-01-01

    Conclusion: The time-locked suppression of beta oscillatory activity in the STN is in line with previous reports of beta ERD prior to voluntary movements. Our results show that the STN is involved in anticipatory grip force control in PD patients. The difference in the phasic beta ERD between the two tasks and the reduction of cortico-subthalamic synchronization suggests that qualitatively different neuronal network states are involved in different grip force control tasks.

  19. Improvement of handle grip using reverse engineering, CAE and Rapid Prototyping

    Directory of Open Access Journals (Sweden)

    Stoklasek Pavel

    2016-01-01

    Full Text Available The overwhelming majority of manual operations is even nowadays performed by using manual hand tools. These tools can be divided into 2 groups – hand tools designed for general use or a single-purpose hand tools for special operations. Tool described in this paper is used in assembling operation in the completion of electric motor. During the design of the existing tools the requirements for a functional part of the tool (lifespan, inability to damage the engine installation were fully considered, demands for ergonomic grip area, however, were not taken into account. Long-term use of incorrectly designed tool causes carpal tunnel syndrome, hand-arm vibration syndrome, diminished sensitivity or tingling in the fingers of workers. These difficulties can be reduced or entirely eliminated due to proper design of the grip of hand tool. Most authors focus on adjusting the grip for optimum ergonomics at individual types of grips (cylindrical, palmar, lateral, etc.. However, as already mentioned, there are tools for specific operations when the working area is limited by space or a specific type of load on the grip is needed. In some cases, it is often necessary to change the type of grip or combine different types of grips. This paper describes the design of an optimal grip of hand tool used for specific operation when assembling motors. Design of prototype mold and production of functional prototypes for ergonomics assessment directly in the workplace were realized. New design of handle should reduce the risk primarily of developing carpal tunnel in long-term use.

  20. Stephen Hawking, the Grand Design and the mass media communication: Philosophy, Science and Religion

    Directory of Open Access Journals (Sweden)

    Leandro Sequeiros

    2014-11-01

    Full Text Available The return of summer vacances 2010 coincide with the notice concerning the inminent publication of a provocative and scandalous book by the eminent Phisicist Stephen Hawking. The Grand Design came out on September 7 in EE.UU. and on 9 in United Kingdom. On November 15th, the Spanish edition have been issued. The Spanish newpapers have published some fragments, which apparently show Hawking intends to prove scientifically that God not exists. The communications media remark by different ways the scarce frangments of the text: «God is not necessary», «Hawking proves God not exists», «Creator God is a destroyed mith», «Hawking scientifically proves God not exists», «God expeled of the Universe»… We have tracked more than hundred web-pages in which the contents of Hawking book are comment. Rationalists and religious sectors have standed in the debate. But, what has Hawking really defended in The Grand Design?

  1. Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera.

    Science.gov (United States)

    Tan, K; Radloff, S E; Li, J J; Hepburn, H R; Yang, M X; Zhang, L J; Neumann, P

    2007-06-01

    The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.

  2. Pain-Suppressed Behaviors in the Red-tailed Hawk 1 (Buteo jamaicensis).

    Science.gov (United States)

    Mazor-Thomas, Jana E; Mann, Phyllis E; Karas, Alicia Z; Tseng, Flo

    2014-03-01

    Our ability to provide analgesia in wild and exotic patients is hampered by a lack of species-specific information on effective drugs and protocols. One contributing factor is the difficulty of applying data from traditional laboratory tests of nociception to clinical conditions frequently involving combinations of inflammatory, mechanical, and neuropathic pain. Pain-suppressed behaviors have become a valuable predictor of clinical utility in other species; in this study we extend this framework to red -tailed hawks in a wildlife hospital, in an attempt to develop a new, humane testing method for birds of prey. We scored six behaviors in hawks hospitalized either for orthopedic trauma or for non-painful conditions. These behaviors included: movement about the cage, grooming, head motions, foot shifts, beak clacks, and rouse. Movement, head motions, and beak clacks were all significantly reduced in hawks with recent orthopedic injury, but not in hawks with healed or minor injuries (Pred -tailed hawks with recent orthopedic trauma show consistent and marked red uctions in several normal maintenance behaviors. Head movements, reported for the first time in this study as a potential marker of pain in birds, in particular seem to be insensitive to sedative side effects of buprenorphine, while being a sensitive measu re of affective state in hawks with painful injuries. These behaviors can be scored humanely and with minimal expense, and should be considered for further research on pain and analgesia in avian species.

  3. Bee-hawking by the wasp, Vespa velutina, on the honeybees Apis cerana and A. mellifera

    Science.gov (United States)

    Tan, K.; Radloff, S. E.; Li, J. J.; Hepburn, H. R.; Yang, M. X.; Zhang, L. J.; Neumann, P.

    2007-06-01

    The vespine wasps, Vespa velutina, specialise in hawking honeybee foragers returning to their nests. We studied their behaviour in China using native Apis cerana and introduced A. mellifera colonies. When the wasps are hawking, A. cerana recruits threefold more guard bees to stave off predation than A. mellifera. The former also utilises wing shimmering as a visual pattern disruption mechanism, which is not shown by A. mellifera. A. cerana foragers halve the time of normal flight needed to dart into the nest entrance, while A. mellifera actually slows down in sashaying flight manoeuvres. V. velutina preferentially hawks A. mellifera foragers when both A. mellifera and A. cerana occur in the same apiary. The pace of wasp-hawking was highest in mid-summer but the frequency of hawking wasps was three times higher at A. mellifera colonies than at the A. cerana colonies. The wasps were taking A. mellifera foragers at a frequency eightfold greater than A. cerana foragers. The final hawking success rates of the wasps were about three times higher for A. mellifera foragers than for A. cerana. The relative success of native A. cerana over European A. mellifera in thwarting predation by the wasp V. velutina is interpreted as the result of co-evolution between the Asian wasp and honeybee, respectively.

  4. PICK1 interacts with ABP/GRIP to regulate AMPA receptor trafficking.

    Science.gov (United States)

    Lu, Wei; Ziff, Edward B

    2005-08-04

    PICK1 and ABP/GRIP bind to the AMPA receptor (AMPAR) GluR2 subunit C terminus. Transfer of the receptor from ABP/GRIP to PICK1, facilitated by GluR2 S880 phosphorylation, may initiate receptor trafficking. Here we report protein interactions that regulate these steps. The PICK1 BAR domain interacts intermolecularly with the ABP/GRIP linker II region and intramolecularly with the PICK1 PDZ domain. Binding of PKCalpha or GluR2 to the PICK1 PDZ domain disrupts the intramolecular interaction and facilitates the PICK1 BAR domain association with ABP/GRIP. Interference with the PICK1-ABP/GRIP interaction impairs S880 phosphorylation of GluR2 by PKC and decreases the constitutive surface expression of GluR2, the NMDA-induced endocytosis of GluR2, and recycling of internalized GluR2. We suggest that the PICK1 interaction with ABP/GRIP is a critical step in controlling GluR2 trafficking.

  5. Adductor pollicis muscle and hand grip strength: potential methods of nutritional assessment in outpatients with stroke

    Directory of Open Access Journals (Sweden)

    Débora Rocha Oliveira

    2010-12-01

    Full Text Available Objective: To evaluate and compare the effectiveness of different methods used for nutritional assessment of outpatients who had hemiplegic stroke. Methods: A cross-section study with adult and elderly patients of both genders enrolled in a rehabilitation center. The analyzed variables were anthropometric measurements, bioelectrical impedance, hand grip strength and thickness of the adductor pollicis muscle. The Pearson χ2 test was used to check the association between variables with a significance level of α = 5%. Results: When evaluating the association between indicators of muscle mass, it was observed that the hand grip strength in both genders was positively correlated with arm muscle circumference (p = 0.0196 and lean mass (p = 0.0002. Fat mass measured by the bioelectrical impedance method already showed a significant inverse relationship with the grip (r = -0.3879. The thickness of the adductor pollicis muscle showed significant association with lean mass (p = 0.0052 and hand grip (p = 0.0024. Conclusion: In this study, the hand grip strength and thickness of the adductor pollicis muscle were well correlated with measurements determined by anthropometry and bioimpedance. The results show the applicability of grip strength and thickness of the adductor pollicis muscle in clinical practice as nutritional assessment methods for this population, especially elderly patients, since they detect functional changes not captured by other parameters in the short term and are important for early identification of risk nutrition.

  6. [Isometric grip strength and social gerontological research: results and analytic potentials of SHARE and SOEP].

    Science.gov (United States)

    Hank, K; Jürges, H; Schupp, J; Wagner, G G

    2009-04-01

    This paper shows that the measurement of hand grip strength provides a non-invasive and reliable objective health indicator for social science research and is easy to collect in general population surveys. Grip strength is not only a useful complement of self-reported indicators of health, but it also exhibits a considerable predictive power with regard to a number of further relevant variables for social gerontological research, such as mortality risks. New data from the 2004 Survey of Health, Ageing and Retirement in Europe (SHARE) and the 2006 wave of the German Socio-Economic Panel Study (SOEP) allow insightful methodological and very first substantive cross-sectional analyses of grip strength in Germany. The focus of the present study is on the analysis of individuals aged 50 or older. The experience of both surveys when measuring grip strength is consistently positive, particularly with regard to the respondents' feedback. Major determinants of isometric grip strength are - beyond the individual's gender - age, body size and weight. A multivariate analysis also provides evidence for a clear positive association between various health indicators and grip strength.

  7. Control of grip force and vertical posture while holding an object and being perturbed.

    Science.gov (United States)

    Chen, Bing; Lee, Yun-Ju; Aruin, Alexander S

    2016-11-01

    We investigated motor control perspectives of coordinating maintenance of posture and application of grip force when holding an object and being perturbed. Ten subjects stood on the force platform holding an instrumented object in their dominant hand and were exposed to an external perturbation applied to their shoulders. Task demands were manipulated by positioning a slippery cap on top of the instrumented object. Grip force applied to the object, the object acceleration and the center of pressure (COP) were recorded and analyzed during the time intervals typical for the anticipatory (APA) and compensatory (CPA) components of postural control. Onsets of grip force were seen before the onsets of the COP displacement and initiation of movements of the handheld object during the APA phase of postural control, while the onsets of maximum grip force preceded the maximum COP displacement during the CPA phase. When the task demands increased by holding a handheld object with the slippery cap, subjects tended to generate grip force earlier and of a smaller magnitude; also, the COP displacement in the APA phase was smaller as compared to holding a handheld object only. The outcome provides a foundation for future studies of maintenance of vertical posture in people with impairments of balance and grip force control when holding an object and being perturbed.

  8. Hold, grasp, clutch or grab: consumer grip choices during food container opening.

    Science.gov (United States)

    Rowson, J; Yoxall, A

    2011-07-01

    Society is ageing and sadly that ageing leads to a host of issues, not least a society in which the majority are likely to have some loss of strength and dexterity. This can lead to complications in undertaking everyday tasks such as using transport, bathing or even handling and opening food. Packaging has to provide a multitude of services; to protect and preserve the product, to provide information to the consumer and not least to allow access to the contents. This access to packaging--or 'openability'--has become a significant issue for designers and manufacturers with the change in demographics as described above. Understanding the choices consumers make in how they manipulate packaging can help designers produce packaging that is more able to meet the requirements of modern society. Studies previously undertaken by the authors showed that consumers did use different grips when opening packaging and that certain grips were theoretically more comfortable and stronger than others. This paper outlines a further study whereby consumers were asked to apply the most common grips to a specially designed torque measuring device. Details were taken about the consumers: age, gender, occupation, hand size, plus their preferred grip choice for packaging of this type. The study showed that typically women chose a grip that maximised their opportunity of opening the closure and that this grip choice was more limited than that available for men. This has implications for inclusive design of many everyday products.

  9. Evaluation of total grip strength and individual finger forces on opposing (A-type) handles among Koreans.

    Science.gov (United States)

    Kong, Yong-Ku; Seo, Min-Tae; Kang, Hyun-Sung

    2014-01-01

    The present study evaluated the effect of grip span on finger forces and defined the best grip span for maximising total grip strength based on the finger forces and subjective discomfort in a static exertion. Five grip spans (45, 50, 55, 60 and 65 mm) of the opposing (A-type) handle shape were tested in this study to measure total grip strength and individual finger force among Korean population. A total of 30 males who participated in this study were asked to exert a maximum grip force with two repetitions, and to report the subjective discomfort experienced between exertions using the Borg's CR-10 scale. The highest grip strength was obtained at 45 mm and 50 mm grip spans. Results also showed that forces of all fingers, except for the middle finger force, significantly differed over the grip spans. The lowest subjective discomfort was observed in the 50 mm grip span. The results might be used as development guidelines for ergonomic opposing (A-type) hand tools for Korean population.

  10. Posture, Flexibility and Grip Strength in Horse Riders

    Directory of Open Access Journals (Sweden)

    Hobbs Sarah Jane

    2014-10-01

    Full Text Available Since the ability to train the horse to be ambidextrous is considered highly desirable, rider asymmetry is recognized as a negative trait. Acquired postural and functional asymmetry can originate from numerous anatomical regions, so it is difficult to suggest if any is developed due to riding. The aim of this study was therefore to assess symmetry of posture, strength and flexibility in a large population of riders and to determine whether typical traits exist due to riding. 127 right handed riders from the UK and USA were categorized according to years riding (in 20 year increments and their competition level (using affiliated test levels. Leg length, grip strength and spinal posture were measured and recorded by a physiotherapist. Standing and sitting posture and trunk flexibility were measured with 3-D motion capture technology. Right-left differences were explored in relation to years riding and rider competitive experience. Significant anatomical asymmetry was found for the difference in standing acromion process height for a competition level (-0.07±1.50 cm Intro/Prelim; 0.02±1.31 cm Novice; 0.43±1.27 cm Elementary+; p=0.048 and for sitting iliac crest height for years riding (-0.23±1.36 cm Intro/Prelim; 0.01±1.50 cm Novice; 0.86±0.41 cm Elementary+; p=0.021. For functional asymmetry, a significant interaction was found for lateral bending ROM for years riding x competition level (p=0.047. The demands on dressage riders competing at higher levels may predispose these riders to a higher risk of developing asymmetry and potentially chronic back pain rather than improving their symmetry

  11. Genetic influences on the development of grip strength in adolescence.

    Science.gov (United States)

    Isen, Joshua; McGue, Matt; Iacono, William

    2014-06-01

    Enhanced physical strength is a secondary sex characteristic in males. Sexual dimorphism in physical strength far exceeds sex differences in stature or total body mass, suggesting a legacy of intense sexual selection. Upper-body strength is a particularly promising marker of intrasexual competitiveness in young men. Consequently, it is assumed that sex-influenced gene expression contributes to the development of physical strength. It is unclear, however, whether the underlying sources of individual differences in strength development are comparable across sex. We obtained three measurements of hand-grip strength (HGS) over a six-year period spanning adolescence in male and female same-sex twins (N = 2,513). Biometrical latent growth models were used to partition the HGS variance at age 11 (intercept) and its growth over time (slope) into genetic and environmental components. Results demonstrated that variance around the intercept was highly heritable in both males and females (88% and 79%, respectively). In males, variance around the slope exceeded that of the intercept, while the reverse held for females. Additive genetic effects accounted for most (80%) of the variance around the slope in males, but were of less importance in females (heritability = 28%). Absolute genetic variance around the slope was nearly nine-fold higher in males. This striking disparity suggests that the developmental processes shaping HGS growth are different between the sexes. We propose that this might account for the sex-specific pattern of associations between HGS and external measures (e.g., digit ratio and physical aggression) typically reported in the literature. Our results underscore the role of endogenous androgenic influences in the development of physical strength.

  12. Posture, flexibility and grip strength in horse riders.

    Science.gov (United States)

    Hobbs, Sarah Jane; Baxter, Joanna; Broom, Louise; Rossell, Laura-Ann; Sinclair, Jonathan; Clayton, Hilary M

    2014-09-29

    Since the ability to train the horse to be ambidextrous is considered highly desirable, rider asymmetry is recognized as a negative trait. Acquired postural and functional asymmetry can originate from numerous anatomical regions, so it is difficult to suggest if any is developed due to riding. The aim of this study was therefore to assess symmetry of posture, strength and flexibility in a large population of riders and to determine whether typical traits exist due to riding. 127 right handed riders from the UK and USA were categorized according to years riding (in 20 year increments) and their competition level (using affiliated test levels). Leg length, grip strength and spinal posture were measured and recorded by a physiotherapist. Standing and sitting posture and trunk flexibility were measured with 3-D motion capture technology. Right-left differences were explored in relation to years riding and rider competitive experience. Significant anatomical asymmetry was found for the difference in standing acromion process height for a competition level (-0.07±1.50 cm Intro/Prelim; 0.02±1.31 cm Novice; 0.43±1.27 cm Elementary+; p=0.048) and for sitting iliac crest height for years riding (-0.23±1.36 cm Intro/Prelim; 0.01±1.50 cm Novice; 0.86±0.41 cm Elementary+; p=0.021). For functional asymmetry, a significant interaction was found for lateral bending ROM for years riding x competition level (p=0.047). The demands on dressage riders competing at higher levels may predispose these riders to a higher risk of developing asymmetry and potentially chronic back pain rather than improving their symmetry.

  13. Stable occupancy by breeding hawks (Buteo spp.) over 25 years on a privately managed bunchgrass prairie in northeastern Oregon, USA

    Science.gov (United States)

    Kennedy, Patricia L.; Bartuszevige, Anne M.; Houle, Marcy; Humphrey, Ann B.; Dugger, Katie M.; Williams, John

    2014-01-01

    Potential for large prairie remnants to provide habitat for grassland-obligate wildlife may be compromised by nonsustainable range-management practices. In 1979–1980, high nesting densities of 3 species of hawks in the genus Buteo—Ferruginous Hawk (Buteo regalis), Red-tailed Hawk (B. jamaicensis), and Swainson's Hawk (B. swainsoni)—were documented on the Zumwalt Prairie and surrounding agricultural areas (34,361 ha) in northeastern Oregon, USA. This area has been managed primarily as livestock summer range since it was homesteaded. Unlike in other prairie remnants, land management on the Zumwalt Prairie was consistent over the past several decades; thus, we predicted that territory occupancy of these 3 species would be stable. We also predicted that territory occupancy would be positively related to local availability of nesting structures within territories. We evaluated these hypotheses using a historical dataset, current survey and habitat data, and occupancy models. In support of our predictions, territory occupancy of all 3 species has not changed over the study period of ∼25 yr, which suggests that local range-management practices are not negatively affecting these taxa. Probability of Ferruginous Hawk occupancy increased with increasing area of aspen, an important nest structure for this species in grasslands. Probability of Swainson's Hawk occupancy increased with increasing area of large shrubs, and probability of Red-tailed Hawk occupancy was weakly associated with area of conifers. In the study area, large shrubs and conifers are commonly used as nesting structures by Swainson's Hawks and Red-tailed Hawks, respectively. Availability of these woody species is changing (increases in conifers and large shrubs, and decline in aspen) throughout the west, and these changes may result in declines in Ferruginous Hawk occupancy and increases in Swainson's Hawk and Red-tailed Hawk occupancy in the future.

  14. Theories of Everything and Hawking's Wave Function of the Universe

    CERN Document Server

    Hartle, J B

    2002-01-01

    If a cat, a cannonball, and an economics textbook are all dropped from the same height, they fall to the ground with exactly the same acceleration under the influence of gravity. This equality of gravitational accelerations of different things is one of the most accurately tested laws of physics. That law, however, tells us little about cats, cannonballs, or economics. This lecture expands on this theme to address the question of what features of our world are predicted by a fundamental ``theory of everything'' governing the regularities exhibited universally by all physical systems. This may consist of two parts: a dynamical law governing regularities in time (e.g superstring theory) and a law of cosmological initial condition governing mostly regularities in space (e.g. Hawking's no-boundary initial condition). The lecture concludes that: (1) ``A theory of everything'' is not a theory of everything in a quantum mechanical universe. (2) If the laws are short enough to be discoverable then they are probably t...

  15. Hawking radiation with dispersion versus breakdown of WKB

    CERN Document Server

    Schützhold, R

    2013-01-01

    Inspired by the condensed matter analogues of black holes (a.k.a. dumb holes), we study Hawking radiation in the presence of a modified dispersion relation which becomes super-luminal at large wave-numbers. In the usual stationary coordinates $(t,x)$, one can describe the asymptotic evolution of the wave-packets in WKB, but this WKB approximation breaks down in the vicinity of the horizon, thereby allowing for a mixing between initial and final creation and annihilation operators. Thus, one might be tempted to identify this point where WKB breaks down with the moment of particle creation. However, using different coordinates $(\\tau,U)$, we find that one can evolve the waves so that WKB in these coordinates is valid throughout this transition region -- which contradicts the above identification of the breakdown of WKB as the cause of the radiation. Instead, our analysis suggests that the tearing apart of the waves into two different asymptotic regions (inside and outside the horizon) is the major ingredient of...

  16. Search for QCD Hawking Radiation in Heavy Ion Collisions

    Science.gov (United States)

    Stiles, Laura; Murray, Michael

    2008-04-01

    A wide variety of measurements at RHIC, for example v2 and energy loss, suggest that the partonic matter created in heavy collisions thermalizes early. One possible mechanism for this is the creation of the QCD analogue to gravitational black holes [1]. Such objects have no memory of their creation and radiate with a characteristic temperature, T, that can depend only on their energy, charge, and angular momentum. This hypothesis is consistent with the growth of multiplicity with s in e+e- collisions and thermal temperature observed at LEP. For central heavy ion collisions the angular momentum of the system is approximately zero and the model predicts a universal dependence of the chemical freezeout temperature on the ratios of charge to transverse energy. To test this prediction against BRAHMS data, We have fitted data on π, K, p and p from central Au + Au collisions at several rapidities and energies, using the THERMUS code. The experimental dependence of the temperature on the ratio of charge to transverse energy will be compared to the Hawking radiation predictions. By comparing data sets at different energy, centrality and rapidity we can select systems with the same ratio of baryon number to energy but different rapidities. This may allow us to test for any effect of angular momentum on temperature. [1] P. Castorina, D. Kharzeev and H. Satz, Eur. Phys. J. C 52, 187 (2007)

  17. The three-body problem from Pythagoras to Hawking

    CERN Document Server

    Valtonen, Mauri; Kholshevnikov, Konstantin; Mylläri, Aleksandr; Orlov, Victor; Tanikawa, Kiyotaka

    2016-01-01

    This book, written for a general readership, reviews and explains the three-body problem in historical context reaching to latest developments in computational physics and gravitation theory. The three-body problem is one of the oldest problems in science and it is most relevant even in today’s physics and astronomy. The long history of the problem from Pythagoras to Hawking parallels the evolution of ideas about our physical universe, with a particular emphasis on understanding gravity and how it operates between astronomical bodies. The oldest astronomical three-body problem is the question how and when the moon and the sun line up with the earth to produce eclipses. Once the universal gravitation was discovered by Newton, it became immediately a problem to understand why these three-bodies form a stable system, in spite of the pull exerted from one to the other. In fact, it was a big question whether this system is stable at all in the long run. Leading mathematicians attacked this problem over more than...

  18. Permeable Surface Corrections for Ffowcs Williams and Hawkings Integrals

    Science.gov (United States)

    Lockard, David P.; Casper, Jay H.

    2005-01-01

    The acoustic prediction methodology discussed herein applies an acoustic analogy to calculate the sound generated by sources in an aerodynamic simulation. Sound is propagated from the computed flow field by integrating the Ffowcs Williams and Hawkings equation on a suitable control surface. Previous research suggests that, for some applications, the integration surface must be placed away from the solid surface to incorporate source contributions from within the flow volume. As such, the fluid mechanisms in the input flow field that contribute to the far-field noise are accounted for by their mathematical projection as a distribution of source terms on a permeable surface. The passage of nonacoustic disturbances through such an integration surface can result in significant error in an acoustic calculation. A correction for the error is derived in the frequency domain using a frozen gust assumption. The correction is found to work reasonably well in several test cases where the error is a small fraction of the actual radiated noise. However, satisfactory agreement has not been obtained between noise predictions using the solution from a three-dimensional, detached-eddy simulation of flow over a cylinder.

  19. Omega-deformed SYM on a Gibbons-Hawking Space

    CERN Document Server

    Dey, Anindya

    2014-01-01

    We study an $\\mathcal{N}=2$, pure $U(1)$ SYM theory on a Gibbons-Hawking space $\\Omega$-deformed using the $U(1)$ isometry. The resultant 3D theory, after an appropriate "Nekrasov-Witten" change of variables, is asymptotically equivalent to the undeformed theory at spatial infinity but differs from it as one approaches the NUT centers which are fixed points under the $U(1)$ action. The 3D theory may be recast in the form of a generalized hyperk\\"ahler sigma model introduced in \\cite{Dey:2014lja} where the target space is a one-parameter family of hyperk\\"ahler spaces. The hyperk\\"ahler fibers have a preferred complex structure which for the deformed theory depends on the parameter of $\\Omega$-deformation. The metric on the hyperk\\"ahler fiber can be reduced to a standard metric on $\\mathbb{C} \\times T^2$ with the modular parameter of the torus depending explicitly on the $\\Omega$-deformation parameter. The contribution of the NUT center to the sigma model path integral, expected to be a holomorphic section of...

  20. Normative Measurements of Grip and Pinch Strengths of 21st Century Korean Population

    Directory of Open Access Journals (Sweden)

    Jin Hee Shim

    2013-01-01

    Full Text Available BackgroundMeasuring grip and pinch strength is an important part of hand injury evaluation. Currently, there are no standardized values of normal grip and pinch strength among the Korean population, and lack of such data prevents objective evaluation of post-surgical recovery in strength. This study was designed to establish the normal values of grip and pinch strength among the healthy Korean population and to identify any dependent variables affecting grip and pinch strength.MethodsA cross-sectional study was carried out. The inclusion criterion was being a healthy Korean person without a previous history of hand trauma. The grip strength was measured using a Jamar dynamometer. Pulp and key pinch strength were measured with a hydraulic pinch gauge. Intra-individual and inter-individual variations in these variables were analyzed in a standardized statistical manner.ResultsThere were a total of 336 healthy participants between 13 and 77 years of age. As would be expected in any given population, the mean grip and pinch strength was greater in the right hand than the left. Male participants (137 showed mean strengths greater than female participants (199 when adjusted for age. Among the male participants, anthropometric variables correlated positively with grip strength, but no such correlations were identifiable in female participants in a statistically significant way.ConclusionsObjective measurements of hand strength are an important component of hand injury evaluation, and population-specific normative data are essential for clinical and research purposes. This study reports updated normative hand strengths of the South Korean population in the 21st century.

  1. Patterns and processes of diversification in a widespread and ecologically diverse avian group, the buteonine hawks (Aves, Accipitridae).

    Science.gov (United States)

    do Amaral, Fábio Raposo; Sheldon, Frederick H; Gamauf, Anita; Haring, Elisabeth; Riesing, Martin; Silveira, Luís F; Wajntal, Anita

    2009-12-01

    Buteonine hawks represent one of the most diverse groups in the Accipitridae, with 58 species distributed in a variety of habitats on almost all continents. Variations in migratory behavior, remarkable dispersal capability, and unusual diversity in Central and South America make buteonine hawks an excellent model for studies in avian evolution. To evaluate the history of their global radiation, we used an integrative approach that coupled estimation of the phylogeny using a large sequence database (based on 6411 bp of mitochondrial markers and one nuclear intron from 54 species), divergence time estimates, and ancestral state reconstructions. Our findings suggest that Neotropical buteonines resulted from a long evolutionary process that began in the Miocene and extended to the Pleistocene. Colonization of the Nearctic, and eventually the Old World, occurred from South America, promoted by the evolution of seasonal movements and development of land bridges. Migratory behavior evolved several times and may have contributed not only to colonization of the Holarctic, but also derivation of insular species. In the Neotropics, diversification of the buteonines included four disjunction events across the Andes. Adaptation of monophyletic taxa to wet environments occurred more than once, and some relationships indicate an evolutionary connection among mangroves, coastal and várzea environments. On the other hand, groups occupying the same biome, forest, or open vegetation habitats are not monophyletic. Refuges or sea-level changes or a combination of both was responsible for recent speciation in Amazonian taxa. In view of the lack of concordance between phylogeny and classification, we propose numerous taxonomic changes.

  2. AtGRIP protein locates to the secretory vesicles of trans Golgi-network in Arabidopsis root cap cells

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying; ZHANG Wei; ZHAO Lei; LI Yan

    2008-01-01

    GRIP domain proteins, locating to the trans-Golgi network, are thought to play an essential role in Golgi apparatus trafficking in yeast and animal cells. In the present study, AtGRIP cDNA was amplified by reverse transcriptase PCR from RNA isolated from Arabidopsis seedling. The GST fusion protein of AtGRIP was affinity-purified and its rabbit polyclonal antibody was obtained. Immuno-blotting with the purified anti-AtGRIP polyclonal antibody demonstrated that the molecular mass of AtGRIP protein is about 92 kD, and its expression is not tissue-specific in Arabidopsis. Immunoflourescent labeling and confocal microscopy revealed that the AtGRIP protein was co-localized with Golgi stacks in Arabidop-sis root cells. Immuno-gold labeling and electron microscopy observation showed that AtGRIP protein was mainly located to the membrane of the secretory vesicles of trans-Golgi network in Arabidopsis root cap cells. Taken together, these results indicate that the localization of GRIP domain proteins be-tween plants and animal cells are conserved. These results also suggest that the AtGRIP may be in-volved in regulating the formation or sorting of Golgi-associated vesicles in plant cells.

  3. Grip type and task goal modify reach-to-grasp performance in post-stroke hemiparesis

    Science.gov (United States)

    Schaefer, Sydney Y.; DeJong, Stacey L.; Cherry, Kendra M.; Lang, Catherine E.

    2011-01-01

    This study investigated whether grip type and/or task goal influenced reaching and grasping performance in post-stroke hemiparesis. Sixteen adults with post-stroke hemiparesis and twelve healthy adults reached to and grasped a cylindrical object using one of two grip types (3-finger or palmar) to achieve one of two task goals (hold or lift). Performance of the stroke group was characteristic of hemiparetic limb movement during reach-to-grasp, with more curved handpaths and slower velocities compared to the control group. These effects were present regardless of grip type or task goal. Other measures of reaching (reach time and reach velocity at object contact) and grasping (peak thumb-index finger aperture during the reach and peak grip force during the grasp) were differentially affected by grip type, task goal, or both, despite the presence of hemiparesis, providing new evidence that changes in motor patterns after stroke may occur to compensate for stroke-related motor impairment. PMID:22357103

  4. Grip pressure distributions and associated variability in golf: a two-club comparison.

    Science.gov (United States)

    Langlais, Sean M; Broker, Jeffrey P

    2014-06-01

    Teaching and playing professionals offer multiple theories concerning the manner in which forces should be applied to the handle of the club during the golf swing. This study extends recent research concerning grip pressures and forces in golf, with the purpose of exploring the similarities and differences between force profiles for a 7-iron and driver swung by proficient golfers. A secondary purpose was to further analyze the way that golfers use grip forces to manipulate the club. Grip forces were measured on eight low handicap golfers (USGA indexes 0 to 7) swinging their own 7-irons and drivers. In total, lead-hand and trail-hand grip forces were isolated as well as anatomically specific forces within the hands. Force profile variability across multiple swings for each golfer and between golfers characterized consistencies and important differences. Correlations between 7-iron and driver force profiles characterized force 'signatures.' The data highlight large fluctuations in grip forces during the swing. Marked differences between participants were observed, involving force magnitudes and phasing. Dominant forces arose primarily from the lead hand, specifically the last three fingers. Force profiles were highly repeatable across swings for a golfer (standard deviations high (r2 = 0.86). Notably, within swing force variability was greatest during club acceleration, but dramatically decreased at impact.

  5. Effects of Taping on Pain, Grip Strength and Wrist Extension Force in Patients with Tennis Elbow

    Science.gov (United States)

    Shamsoddini, Alireza; Hollisaz, Mohammad Taghi

    2013-01-01

    Background Tennis elbow (TE) is a common musculotendinous degenerative disorder of the extensor origin at the lateral humeral epicondyle. Different modes of treatment are used for management of tennis elbow. Objectives This study investigated the effect of the taping technique (TT) on pain, grip strength and wrist extension force in treatment of tennis elbow. Patients and Methods Thirty patients (16 men /14 women with a mean age of 32.2 years) with tennis elbow of their dominant arm participated in this study. Outcome measures were assessment of pain at the lateral aspect of the elbow, grip strength and wrist extension force before and five to ten minutes after application of elbow tape on the affected and unaffected arms. A Visual Analog Scale was used to assess pain. A dynamometer and a hand-held dynamometer were used for evaluation of grip strength and wrist extension force, respectively. Results Among the variables, significant differences were found in wrist extension forces between effected and unaffected arms (P = 0.02). Changes in grip strength showed statically significant improvements in the affected arm compared to the unaffected arm (P = 0.03). Also, in assessment of pain at the lateral epicondyle, the mean change between affected and unaffected arms was significant, with P = 0.001. Conclusions The taping technique, as applied in this study demonstrates an impressive effect on wrist extension force and grip strength of patients with TE. Elbow taping also reduces pain at the lateral aspect of the elbow in these patients. PMID:24350156

  6. Proposed technique for inguinal hernia repair with self-gripping mesh: avoiding fixation to undesired structures.

    Science.gov (United States)

    Porrero, J L; Cano-Valderrama, O; Castillo, M J; Alonso, M T

    2015-10-01

    Self-gripping meshes have been developed to avoid fixing sutures during inguinal hernia repair. Operative time is shorter when using a self-gripping mesh than with conventional Lichtenstein repair. However, these meshes can be difficult to handle because they fix to undesired structures. The aim of this report is to describe a new technique to avoid this problem. Inguinal hernia dissection is made as usual. Once dissection is finished, a Parietex ProGrip(®) (Covidien, Dublin, Ireland) flat sheet mesh is cut depending on the size needed. A small split is made between the lower and medium third of the mesh to mark where the split for the spermatic cord will be. Using this mark, the upper third of the mesh is folded over the medium third, hiding the microgrips that make this a self-gripping mesh. In this way, only the lower third of the mesh has the microgrips exposed and the mesh can be fixed to the pubic bone and inguinal ligament without fixation to undesired structures. Once the lower third of the mesh is fixed, the split for the spermatic cord is completed and the upper part of the mesh is passed below the spermatic cord. Then, the mesh is unfolded to expose the microgrips again and the medium and upper third of the mesh are descended to its final position. This proposed technique for inguinal hernia repair with self-gripping mesh makes the surgery easier, avoiding mesh fixation to undesired structures.

  7. Slip detection and grip adjustment using optical tracking in prosthetic hands.

    Science.gov (United States)

    Roberts, Luke; Singhal, Girish; Kaliki, Rahul

    2011-01-01

    We have designed a closed loop control system that adjusts the grasping force of a prosthetic hand based on the amount of object slip detected by an optical tracking sensor. The system was designed for the i-Limb (a multi-fingered prosthetic hand from Touch Bionics Inc.) and is comprised of an optical sensor embedded inside a silicone prosthetic glove and a control algorithm. In a proof of concept study to demonstrate the effectiveness of optical tracking in slip sensing, we record slip rate while increasing the weight held in the grasp of the hand and compare two cases: grip adjustment on and grip adjustment off. The average slip rate was found to be 0.314 slips/(s · oz) without grip adjustment and 0.0411 slips/(s · oz) with grip adjustment. This paper discusses the advantages of the optical approach in slip detection and presents the experiment and results utilizing the optical sensor and grip control algorithm.

  8. Productivity, mortality, and response to disturbance of nesting Swainson's hawks on the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Poole, L.D.; Marr, N.V.; McCorquodale, S.M.

    1988-03-01

    The objectives of this study were to characterize Swainson's hawk (Buteo swainson) use of the US Department of Energy (DOE) Hanford Site and to evaluate the potential for engineering and other human activities on the Hanford Site to negatively affect the nesting Swainson's hawk population. Activities associated with the Basalt Waste Isolation Project (BWIP) were used as the primary external stimuli in studying hawk responses to potential human disturbance. Parked and moving vehicles were the most common disturbance sources observed in Swainson's hawk territories. Hawks appeared to be sensitive to disturbance from pedestrians and slow-moving vehicles near nests. Novel stimuli were much more likely to evoke strong responses than were recurring events. Adult hawks reacted more frequently and vigorously than did juveniles. When disturbed, adult hawks usually flew toward the location of the disturbance; juvenile hawks usually flew away from disturbances. Human activity associated with BWIP may have had negative on one pair of nesting Swainson's hawks and may have precluded the use of an additional traditional nesting territory. Negative impacts to nesting Swainson's hawks from human activity could be minimized by confining activities to the non-nesting period or to distances greater than 2.2 km from nest sites. Tree groves and elevated perches, including utility poles, across the Hanford Site are probably critical to the success of nesting Swainson's hawks. Potential mitigation strategies associated with energy research and development activities on the Hanford Site could include provisions for maintenance and establishment of drought-tolerant trees and native vegetation. 22 refs., 5 figs., 3 tabs.

  9. Behavioral ecology of the Swainson's Hawk (Buteo swainsoni) in Washington

    Energy Technology Data Exchange (ETDEWEB)

    Fitzner, R.E.

    1980-12-01

    This study examines the breeding ecology and behavior of the Swainson's Hawk (Buteo swainsoni) on its breeding ground in southeastern Washington. Seasonal movements and distribution of the buteo are also described. The birds were observed from blinds, or filmed by Super-8mm time-lapse cameras, during courtship, nest building, egg laying, incubation, and nestling and post-fledging development. Food habits were examined during the nestling and post-fledging periods. Snakes, especially the abundant Western Yellow-bellied racers, were a prey staple, and insects became an important food source during the post-fledging period. It was apparent that Swainson's Hawks feed on smaller and more diverse prey than sympatric buteos (Red-tailed and Ferruginous Hawks), thus reducing competition with neighboring congenerics. Interactions with buteos and other raptor genera were observed, and nearest neighbor distances measured. Organochlorine pesticides in prey species consumed by Swainson's Hawks are concentrated from prey to predator through the food chain. The hawk pellets (regurgitated castings) would contain those concentrations and could easily be monitored without sacrificing any part of the food chain.

  10. Red-tailed Hawk movements and use of habitat in the Luquillo Mountains of Puerto Rico

    Science.gov (United States)

    Vilella, Francisco; Nimitz, Wyatt F.

    2012-01-01

    The Red-tailed Hawk (Buteo jamaicensis) is a top predator of upland ecosystems in the Greater Antilles. Little information exists on the ecology of the insular forms of this widely distributed species. We studied movements and resource use of the Red-tailed Hawk from 2000 to 2002 in the montane forests of northeastern Puerto Rico. We captured 32 and used 21 radio-marked Red-tailed Hawks to delineate home range, core area shifts, and macrohabitat use in the Luquillo Mountains. Red-tailed Hawks in the Luquillo Mountains frequently perched near the top of canopy emergent trees and were characterized by wide-ranging capabilities and extensive spatial overlap. Home range size averaged 5,022.6 6 832.1 ha (305–11,288 ha) and core areas averaged 564.8 6 90.7 ha (150–1,230 ha). This species had large mean weekly movements (3,286.2 6 348.5 m) and a preference for roadside habitats. Our findings suggest fragmentation of contiguous forest outside protected areas in Puerto Rico may benefit the Red-tailed Hawk

  11. Characterization of Sarcocystis from four species of hawks from Georgia, USA.

    Science.gov (United States)

    Yabsley, Michael J; Ellis, Angela E; Stallknecht, David E; Howerth, Elizabeth W

    2009-02-01

    During 2001 to 2004, 4 species of hawks (Buteo and Accipiter spp.) from Georgia were surveyed for Sarcocystis spp. infections by examining intestinal sections. In total, 159 of 238 (66.8%) hawks examined were infected with Sarcocystis spp. Samples from 10 birds were characterized by sequence analysis of a portion of the 18S rRNA gene (783 base pairs). Only 3 of the 10 sequences from the hawks were identical; the remainder differed by at least 1 nucleotide. Phylogenetic analysis failed to resolve the position of the hawk Sarcocystis species, but they were closely related several Sarcocystis species from raptors, rodents, and Sarcocystis neurona. The high genetic diversity of Sarcocystis suggests that more than 1 species infects these 4 hawk species; however, additional molecular or experimental work will be required to determine the speciation and diversity of parasites infecting these avian hosts. In addition to assisting with determining species richness of Sarcocystis in raptors, molecular analysis should be useful in the identification of potential intermediate hosts.

  12. Identifying habitat sinks: A case study of Cooper's hawks in an urban environment

    Science.gov (United States)

    Mannan, R.W.; Steidl, R.J.; Boal, C.W.

    2008-01-01

    We studied a population of Cooper's hawks (Accipiter cooperii) in Tucson, Arizona from 1994 to 2005. High rates of mortality of nestlings from an urban-related disease prompted speculation that the area represented an ecological trap and habitat sink for Cooper's hawks. In this paper, we used estimates of survival and productivity from 11years of monitoring to develop an estimate of the rate of population change, ??, for Cooper's hawks in the area. We used a Cormack-Jolly-Seber approach to estimate survival of breeding hawks, and a stochastic, stage-based matrix to estimate ??. Despite the urban-related disease, the estimate of ?? indicated that the area does not function as a habitat sink for Cooper's hawks (?? = 1.11 ?? 0.047; P = 0.0073 for the null of ?? 1). Because data required to reliably identify habitat sinks are extensive and difficult to acquire, we suggest that the concept of habitat sinks be applied cautiously until substantiated with reliable empirical evidence. ?? 2008 Springer Science+Business Media, LLC.

  13. “霍金难题”解读%Illumination of "Hawking Puzzle"

    Institute of Scientific and Technical Information of China (English)

    王伯鲁

    2012-01-01

    Hawking puzzle" has been a technical problem about the future of human race which was brought forward recently by well-known contemporary scientist Stephen Hawking. It has given a broad social impact on the globe. This article has illuminated Hawking puzzle from a philosophical point of view, valued and explained the meaning of Hawking asking. In my opinion, the difficulty of Hawking puzzle are not only to give a 100-year plan to ensure the sustainable development of human race, but also to push implementation effective on this plan.%"霍金难题"是当代著名科学家霍金近期提出的一个关于人类前途的技术性难题,产生了广泛的社会影响。从哲学视角解读霍金难题,评说霍金提问的时代意义,其难点不仅表现在不易从技术上给出一个确保人类持续发展的百年规划,而且还在于我们难于推进这一规划的有效实施。

  14. Red-shouldered hawk occupancy surveys in central Minnesota, USA

    Science.gov (United States)

    Henneman, C.; McLeod, M.A.; Andersen, D.E.

    2007-01-01

    Forest-dwelling raptors are often difficult to detect because many species occur at low density or are secretive. Broadcasting conspecific vocalizations can increase the probability of detecting forest-dwelling raptors and has been shown to be an effective method for locating raptors and assessing their relative abundance. Recent advances in statistical techniques based on presence-absence data use probabilistic arguments to derive probability of detection when it is <1 and to provide a model and likelihood-based method for estimating proportion of sites occupied. We used these maximum-likelihood models with data from red-shouldered hawk (Buteo lineatus) call-broadcast surveys conducted in central Minnesota, USA, in 1994-1995 and 2004-2005. Our objectives were to obtain estimates of occupancy and detection probability 1) over multiple sampling seasons (yr), 2) incorporating within-season time-specific detection probabilities, 3) with call type and breeding stage included as covariates in models of probability of detection, and 4) with different sampling strategies. We visited individual survey locations 2-9 times per year, and estimates of both probability of detection (range = 0.28-0.54) and site occupancy (range = 0.81-0.97) varied among years. Detection probability was affected by inclusion of a within-season time-specific covariate, call type, and breeding stage. In 2004 and 2005 we used survey results to assess the effect that number of sample locations, double sampling, and discontinued sampling had on parameter estimates. We found that estimates of probability of detection and proportion of sites occupied were similar across different sampling strategies, and we suggest ways to reduce sampling effort in a monitoring program.

  15. BOOK REVIEW: Meilensteine der Astronomie - Von Aristoteles bis Hawking

    Science.gov (United States)

    Duerbeck, H. W.; Hamel, J.

    2006-12-01

    A writer, more specific a writer on the history of astronomy, might from time to time look at the collected document folders with all the research material and reprints, and might wonder: has this been all? Especially at a time when recycling is in vogue? And, perhaps with a request or an invitation to submit something, he or she might consider re-using the material before its definitive disposal. Well, such are my feelings when I looked at Jurgen Hamel's new book Milestones of Astronomy - From Aristoteles to Hawking . A slight chance for survival of medium-sized publishers like Kosmos is to offer popular books, and a title must attract potential buyers: Aristoteles means the "old" times, and as concerns the "mad scientist" of modern times, Stephen Hawking has by now dethroned Einstein. In 1998, Hamel had published a Geschichte der Astronomie - Von den Anfangen bis zur Gegenwart (History of astronomy, from the beginnings to the present), which, of course, he could not simply copy. This time, he selected some stones from his research areas - milestones, touchstones, stumbling blocks in the long road of astronomical evolution - and put them between the covers of his new book. So let us look at these (mile)stones . The reader is informed about Aristoteles on 2 pages, but his medieval interpreter Johannes de Sacrobosco gets 8 pages! Copernicus' life and achievements are described on 9 pages, closely followed by his devotee and translator Rothmann with 8 pages; Copernicus' contemporary, Peter Apian, however, gets about 13! Bessel's and Herschel's lifes and works are described on well-deserved 13 and 15 pages, while the achievements of the two Lucasian professors, Isaac Newton and Stephen Hawking, are just outlined in a single paragraph! Thus, importance is sometimes inversely proportional to text length... But let us become serious now. Why should an active historian outline, for the hundreth time, the life of Copernicus, while there are so many interesting, and often

  16. Estimating thumb-index finger precision grip and manipulation potential in extant and fossil primates.

    Science.gov (United States)

    Feix, Thomas; Kivell, Tracy L; Pouydebat, Emmanuelle; Dollar, Aaron M

    2015-05-06

    Primates, and particularly humans, are characterized by superior manual dexterity compared with other mammals. However, drawing the biomechanical link between hand morphology/behaviour and functional capabilities in non-human primates and fossil taxa has been challenging. We present a kinematic model of thumb-index precision grip and manipulative movement based on bony hand morphology in a broad sample of extant primates and fossil hominins. The model reveals that both joint mobility and digit proportions (scaled to hand size) are critical for determining precision grip and manipulation potential, but that having either a long thumb or great joint mobility alone does not necessarily yield high precision manipulation. The results suggest even the oldest available fossil hominins may have shared comparable precision grip manipulation with modern humans. In particular, the predicted human-like precision manipulation of Australopithecus afarensis, approximately one million years before the first stone tools, supports controversial archaeological evidence of tool-use in this taxon.

  17. The Hawk-I UDS and GOODS Survey (HUGS): Survey design and deep K-band number counts

    NARCIS (Netherlands)

    Fontana, A.; Dunlop, J. S.; Paris, D.; Targett, T. A.; Boutsia, K.; Castellano, M.; Galametz, A.; Grazian, A.; McLure, R.; Merlin, E.; Pentericci, L.; Wuyts, S.; Almaini, O.; Caputi, K.; Chary, R. R.; Cirasuolo, M.; Conselice, C. J.; Cooray, A.; Daddi, E.; Dickinson, M.; Faber, S. M.; Fazio, G.; Ferguson, H. C.; Giallongo, E.; Giavalisco, M.; Grogin, N. A.; Hathi, N.; Koekemoer, A. M.; Koo, D. C.; Lucas, R. A.; Nonino, M.; Rix, H. W.; Renzini, A.; Rosario, D.; Santini, P.; Scarlata, C.; Sommariva, V.; Stark, D. P.; van der Wel, A.; Vanzella, E.; Wild, V.; Yan, H.; Zibetti, S.

    2014-01-01

    We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over the CANDELS UDS and GOO

  18. The Hawk-I UDS and GOODS Survey (HUGS) : Survey design and deep K-band number counts

    NARCIS (Netherlands)

    Fontana, A.; Dunlop, J. S.; Paris, D.; Targett, T. A.; Boutsia, K.; Castellano, M.; Galametz, A.; Grazian, A.; McLure, R.; Merlin, E.; Pentericci, L.; Wuyts, S.; Almaini, O.; Caputi, K.; Chary, R. -R.; Cirasuolo, M.; Conselice, C. J.; Cooray, A.; Daddi, E.; Dickinson, M.; Faber, S. M.; Fazio, G.; Ferguson, H. C.; Giallongo, E.; Giavalisco, M.; Grogin, N. A.; Hathi, N.; Koekemoer, A. M.; Koo, D. C.; Lucas, R. A.; Nonino, M.; Rix, H. W.; Renzini, A.; Rosario, D.; Santini, P.; Scarlata, C.; Sommariva, V.; Stark, D. P.; van der Wel, A.; Vanzella, E.; Wild, V.; Yan, H.; Zibetti, S.

    2014-01-01

    We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data (images and catalog) public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging in the K and Y bands over th

  19. Isolation of Erysipelothrix rhusiopathiae from a red-tailed hawk (Buteo jamaicensis) with a concurrent pox virus infection.

    Science.gov (United States)

    Pace, L W; Chengappa, M M; Greer, S; Alderson, C

    1987-10-01

    Erysipelothrix rhusiopathiae was isolated from the spleen, liver, lung, heart, kidney, and skin of a red-tailed hawk (Buteo jamaicensis) which had a concurrent avian pox virus infection. The hawk had been housed on a farm with domestic turkeys, providing a possible source of the E. rhusiopathiae.

  20. Breeding biology and nest-site selection of red-tailed hawks in an altered desert grassland

    Science.gov (United States)

    Hobbs, R.J.; DeStefano, S.; Halvorson, W.L.

    2006-01-01

    Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert grassland in southern Arizona. Our objectives were to determine what environmental characteristics influence Red-tailed Hawk habitat selection in mesquite-invaded desert grasslands and to evaluate the habitat quality of these grasslands for Red-tailed Hawks based on nesting density, nest success, and productivity. Red-tailed Hawks had 86% (95% C.I. = 73-99) nest success and 1.82 young per breeding pair (95% C.I. = 1.41-2.23). Nesting density was 0.15 (95% CI = 0.08-0.21) breeding pairs/km2 and the mean nearest-neighbor distance was 1.95 km (95% C.I. = 1.74-2.16). Red-tailed Hawks selected nest-sites with taller nest-trees and greater tree height and cover than were available at random. Mesquite trees in desert grasslands provide abundant potential nesting structures for Red-tailed Hawks. ?? 2006 The Raptor Research Foundation, Inc.

  1. Hawking-like radiation and the density matrix for an infalling observer during gravitational collapse

    CERN Document Server

    Saini, Anshul

    2016-01-01

    We study time-dependant Hawking-like radiation as seen by an infalling observer during gravitational collapse of a thin shell. We calculate the occupation number of particles whose frequencies are measured in the proper time of an infalling observer in Eddington-Finkelstein coordinates. We solve the equations for the whole process from the beginning of the collapse till the moment when the collapsing shell reaches zero radius. The radiation distribution is not thermal in the whole frequency regime, but it is approximately thermal for the wavelengths of the order of the Schwarzschild radius of the collapsing shell. After the Schwarzschild radius is crossed, the temperature increases without limits as the singularity is approached. We also calculate the density matrix associated with this radiation. It turns out that the off-diagonal correlation terms to the diagonal Hawking's leading order terms are very important. While the trace of the diagonal (Hawking's) density matrix squared decreases during the evolutio...

  2. Hawking versus Unruh effects, or the difficulty of slowly crossing a black hole horizon

    Energy Technology Data Exchange (ETDEWEB)

    Barbado, Luis C. [Quantenoptik, Quantennanophysik und Quanteninformation, Fakultät für Physik,Universität Wien, Boltzmanngasse 5, 1090 Wien (Austria); Departamento de Astronomía Extragaláctica, Instituto de Astrofísica de Andalucía (CSIC),Glorieta de la Astronomía s/n, 18008 Granada (Spain); Barceló, Carlos [Departamento de Astronomía Extragaláctica, Instituto de Astrofísica de Andalucía (CSIC),Glorieta de la Astronomía s/n, 18008 Granada (Spain); Garay, Luis J. [Departamento de Física Teórica II, Facultad de Ciencias Fśicas,Universidad Complutense de Madrid, Ciudad Universitaria,Plaza Ciencias 1, 28040 Madrid (Spain); Departamento de Química y Física Teóricas, Instituto de Estructura de la Materia (CSIC),Serrano 121, 28006 Madrid (Spain); Jannes, Gil [Departamento de Ciencias y Tecnología, Universidad Europea de Madrid,Calle Tajo s/n, 28670 Villaviciosa de Odón, Madrid (Spain)

    2016-10-28

    When analyzing the perception of Hawking radiation by different observers, the Hawking effect becomes mixed with the Unruh effect. The separation of both effects is not always clear in the literature. Here we propose an inconsistency-free interpretation of what constitutes a Hawking effect and what an Unruh effect. An appropriate interpretation is important in order to elucidate what sort of effects a detector might experience depending on its trajectory and the state of the quantum field. Under simplifying assumptions we introduce an analytic formula that separates these two effects. Armed with the previous interpretation we argue that for a free-falling detector to cross the horizon without experiencing high-energy effects, it is necessary that the horizon crossing is not attempted at low velocities.

  3. Hawking fluxes and Anomalies in the Rotating Regular Black Holes with the Time-Delay

    CERN Document Server

    Takeuchi, Shingo

    2016-01-01

    We are going to calculate the flow of the angular momentum and flux of the Hawking radiation in the rotating regular black hole with the time-delay proposed in arXiv:1510.08828, based on the anomaly cancellation. We first try to reduce the field theories to the infinite two-dimensional massless free models in which the anomaly cancellation method is possible, in the three metrics in arXiv:1510.08828. We demonstrate that the two of them can be reduced. We perform the calculation in these two metrics, and obtain the flow of the angular momentum and flux of the Hawking radiation in these two metrics. Our result involves the three effects:~the quantum gravity effect regularizing the gravity sources of the black holes, the black hole rotation, and the time-delay. Hence our result could be considered to correspond to a more realistic Hawking radiations.

  4. Hawking versus Unruh effects, or the difficulty of slowly crossing a black hole horizon

    CERN Document Server

    Barbado, Luis C; Garay, Luis J; Jannes, Gil

    2016-01-01

    When analyzing the perception of Hawking radiation by different observers, the Hawking effect becomes mixed with the Unruh effect. The separation of both effects is not always clear in the literature. Here we propose an inconsistency-free interpretation of what constitutes a Hawking effect and what an Unruh effect. An appropriate interpretation is important in order to elucidate what sort of effects a detector might experience depending on its trajectory and the state of the quantum field. Under simplifying assumptions we introduce an analytic formula that separates these two effects. Armed with the previous interpretation we argue that for a free-falling detector to cross the horizon without experiencing high-energy effects, it is necessary that the horizon crossing is not attempted at low velocities.

  5. A note on a perfect simulation algorithm for marked Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Rasmussen, Jakob Gulddahl

    2004-01-01

    The usual straightforward simulation algorithm for (marked or unmarked) Hawkes processes suffers from edge effect. In this note we describe a perfect simulation algorithm which is partly derived as in Brix and Kendall (2002) and partly using upper and lower processes as in the Propp-Wilson algori......The usual straightforward simulation algorithm for (marked or unmarked) Hawkes processes suffers from edge effect. In this note we describe a perfect simulation algorithm which is partly derived as in Brix and Kendall (2002) and partly using upper and lower processes as in the Propp......-Wilson algorithm (1996), or rather as in the dominated CFTP algorithm by Kendall and Moller (2000). Various monotonicity properties and approximations of the cumulative distribution function for the length of a so-called cluster in a marked Hawkes process play an important role....

  6. The Hawkes process with different excitation functions and its asymptotoc behavior

    DEFF Research Database (Denmark)

    Fierro, Raúl; Leiva, Víctor; Møller, Jesper

    The standard Hawkes process is constructed from a homogeneous Poisson process and using the same exciting function for dierent generations of offspring. We propose an extension of this process by considering different exciting functions. This consideration could be important to be taken into acco......The standard Hawkes process is constructed from a homogeneous Poisson process and using the same exciting function for dierent generations of offspring. We propose an extension of this process by considering different exciting functions. This consideration could be important to be taken...... into account in a number of fields; e.g. in seismology, where main shocks produce aftershocks with possibly different intensities. The main results are devoted to the asymptotic behavior of this extension of the Hawkes process. Indeed, a law of large numbers and a central limit theorem are stated...

  7. More on the conformal mapping of quasi-local masses: The Hawking-Hayward case

    CERN Document Server

    Hammad, Fayçal

    2016-01-01

    The conformal transformation of the Hawking-Hayward quasi-local mass is reexamined. It has been found recently that the conformal transformation of the latter exhibits the 'wrong' conformal factor compared to the way usual masses transform under conformal transformations of spacetime. We show, in analogy with what was found recently for the Misner-Sharp mass, that unlike the purely geometric definition of the Hawking-Hayward mass, the latter exhibits the 'right' conformal factor whenever expressed in terms of its material content via the field equations. The case of conformally invariant scalar-tensor theories of gravity is also examined. The equivalence between the Misner-Sharp mass and the Hawking-Hayward mass for spherically symmetric spacetimes manifests itself by giving identical peculiar behaviors under conformal transformations.

  8. Hawking versus Unruh effects, or the difficulty of slowly crossing a black hole horizon

    Science.gov (United States)

    Barbado, Luis C.; Barceló, Carlos; Garay, Luis J.; Jannes, Gil

    2016-10-01

    When analyzing the perception of Hawking radiation by different observers, the Hawking effect becomes mixed with the Unruh effect. The separation of both effects is not always clear in the literature. Here we propose an inconsistency-free interpretation of what constitutes a Hawking effect and what an Unruh effect. An appropriate interpretation is important in order to elucidate what sort of effects a detector might experience depending on its trajectory and the state of the quantum field. Under simplifying assumptions we introduce an analytic formula that separates these two effects. Armed with the previous interpretation we argue that for a free-falling detector to cross the horizon without experiencing high-energy effects, it is necessary that the horizon crossing is not attempted at low velocities.

  9. New Form of Kerr-Newman Solution and Its Hawking Radiation via Tunneling

    Institute of Scientific and Technical Information of China (English)

    JIANG Qing-Quan; WU Shuang-Qing; YANG Shu-Zheng; CHEN De-You

    2006-01-01

    Parikh-Wilzcek's recent work, which treats the Hawking radiation as semi-classical tunneling processfrom the event horizon of static Schwarzshild and Reissner-Nordstr(o)m black holes, indicates that the factually radiant spectrum deviates from the precisely thermal spectrum after taking the self-gravitation interaction into account. In this paper, we extend Parikh-Wilzcek's work to research the Hawking radiation via tunneling from new form of rotating Kerr-Newman solution and obtain a corrected radiant spectrum, which is related to the change of Bekenstein-Hawking entropy, and is not pure thermal, but is consistent with the underlying unitary theory. Meanwhile, we point out that the information conservation is only suitable for the reversible process and in highly unstable evaporating black hole (irreversible process) the information loss is possible.

  10. More on the conformal mapping of quasi-local masses: the Hawking-Hayward case

    Science.gov (United States)

    Hammad, Fayçal

    2016-12-01

    The conformal transformation of the Hawking-Hayward quasi-local mass is re-examined. It has been found recently that the conformal transformation of the latter exhibits the ‘wrong’ conformal factor compared to the way usual masses transform under conformal transformations of spacetime. We show, in analogy with what was found recently for the Misner-Sharp mass, that unlike the purely geometric definition of the Hawking-Hayward mass, the latter exhibits the ‘right’ conformal factor whenever expressed in terms of its material content via the field equations. The case of conformally invariant scalar-tensor theories of gravity is also examined. The equivalence between the Misner-Sharp mass and the Hawking-Hayward mass for spherically symmetric spacetimes manifests itself by giving identical peculiar behaviors under conformal transformations.

  11. Cardiomyopathy and right-sided congestive heart failure in a red-tailed hawk (Buteo jamaicensis).

    Science.gov (United States)

    Knafo, S Emmanuelle; Rapoport, Gregg; Williams, Jamie; Brainard, Benjamin; Driskell, Elizabeth; Uhl, Elizabeth; Crochik, Sonia; Divers, Stephen J

    2011-03-01

    A 15-year-old female red-tailed hawk (Buteo jamaicensis) was evaluated because of dyspnea, anorexia, and coelomic distension. Diagnostic imaging results confirmed severe coelomic effusion and revealed a markedly dilated right ventricle. The diagnosis was right-sided congestive heart failure. Results of measurements of vitamin E, selenium, lead, zinc, and cardiac troponin levels were normal or nondiagnostic. The hawk was treated with furosemide, antifungal and antimicrobial agents, and supplemental fluids and oxygen, but euthanasia was elected because of the poor prognosis and the practical difficulties associated with intensive case management. To our knowledge, this is the first described case of cardiomyopathy and congestive heart failure in a captive red-tailed hawk.

  12. Anomalies and Hawking fluxes from the black holes of topologically massive gravity

    CERN Document Server

    Porfyriadis, Achilleas P

    2009-01-01

    The anomaly cancelation method proposed by Wilczek et al. is applied to the black holes of topologically massive gravity (TMG) and topologically massive gravito-electrodynamics (TMGE). Thus the Hawking temperature and fluxes of the ACL and ACGL black holes are found. The Hawking temperatures obtained agree with the surface gravity formula. Both black holes are rotating and this gives rise to appropriate terms in the effective U(1) gauge field of the reduced (1+1)-dimensional theory. It is found that the terms in this U(1) gauge field correspond exactly to the correct angular velocities on the horizon of both black holes as well as the correct electrostatic potential of the ACGL black hole. So the results for the Hawking fluxes derived here from the anomaly cancelation method, are in complete agreement with the ones obtained from integrating the Planck distribution.

  13. Hawking radiation from astrophysical black holes to analogous systems in lab

    CERN Document Server

    Belgiorno, Francesco D

    2017-01-01

    The aim of this book is to provide the reader with a guide to Hawking radiation through a dual approach to the problem. In the first part of the book, we summarize some basic knowledge about black holes and quantum field theory in curved spacetime. In the second part, we present a survey of methods for deriving and studying Hawking radiation from astrophysical black holes, from the original calculation by S W Hawking to the most recent contributions involving gravitational anomalies and tunneling. In the third part, we introduce analogue gravity models, with particular attention to dielectric black hole systems, to which the studies of the present authors are devoted. The mutual interchange of knowledge between the aforementioned parts is addressed to render a more comprehensive picture of this very fascinating quantum phenomenon associated with black holes.

  14. Non-equilibrium Landauer transport model for Hawking radiation from a black hole

    Science.gov (United States)

    Nation, P. D.; Blencowe, M. P.; Nori, Franco

    2012-03-01

    We propose that the Hawking radiation energy and entropy flow rates from a black hole can be viewed as a one-dimensional (1D), non-equilibrium Landauer transport process. Support for this viewpoint comes from previous calculations invoking conformal symmetry in the near-horizon region, which give radiation rates that are identical to those of a single 1D quantum channel connected to a thermal reservoir at the Hawking temperature. The Landauer approach shows in a direct way the particle statistics independence of the energy and entropy fluxes of a black hole radiating into vacuum, as well as one near thermal equilibrium with its environment. As an application of the Landauer approach, we show that Hawking radiation gives a net entropy production that is 50% larger than that obtained assuming standard 3D emission into vacuum.

  15. The Trilinear Hamiltonian: A Zero Dimensional Model of Hawking Radiation from a Quantized Source

    CERN Document Server

    Nation, P D

    2010-01-01

    We investigate a quantum parametric amplifier with dynamical pump mode, viewed as a zero-dimensional model of Hawking radiation from an evaporating black hole. The conditions are derived under which the spectrum of particles generated from vacuum fluctuations deviates from the thermal spectrum predicted for the conventional parametric amplifier. We find that significant deviations arise when the pump mode (black hole) has emitted nearly half of its initial energy into the signal (Hawking radiation) and idler (in-falling particle) modes. As a model of black hole dynamics, this finding lends support to the view that late-time Hawking radiation contains information about the quantum state of the black hole and is entangled with the black hole's quantum gravitational degrees of freedom.

  16. The trilinear Hamiltonian: a zero-dimensional model of Hawking radiation from a quantized source

    Energy Technology Data Exchange (ETDEWEB)

    Nation, Paul D; Blencowe, Miles P, E-mail: paul.d.nation@dartmouth.ed [Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States)

    2010-09-15

    We investigate a quantum parametric amplifier with dynamical pump mode, viewed as a zero-dimensional model of Hawking radiation from an evaporating black hole. We derive the conditions under which the spectrum of particles generated from vacuum fluctuations deviates from the thermal spectrum predicted for the conventional parametric amplifier. We find that significant deviations arise when the pump mode (black hole) has emitted nearly half of its initial energy into the signal (Hawking radiation) and idler (in-falling particle) modes. As a model of black hole dynamics, this finding lends support to the view that late-time Hawking radiation contains information about the quantum state of the black hole and is entangled with the black hole's quantum gravitational degrees of freedom.

  17. Extraction of time and frequency features from grip force rates during dexterous manipulation.

    Science.gov (United States)

    Mojtahedi, Keivan; Fu, Qiushi; Santello, Marco

    2015-05-01

    The time course of grip force from object contact to onset of manipulation has been extensively studied to gain insight into the underlying control mechanisms. Of particular interest to the motor neuroscience and clinical communities is the phenomenon of bell-shaped grip force rate (GFR) that has been interpreted as indicative of feedforward force control. However, this feature has not been assessed quantitatively. Furthermore, the time course of grip force may contain additional features that could provide insight into sensorimotor control processes. In this study, we addressed these questions by validating and applying two computational approaches to extract features from GFR in humans: 1) fitting a Gaussian function to GFR and quantifying the goodness of the fit [root-mean-square error, (RMSE)]; and 2) continuous wavelet transform (CWT), where we assessed the correlation of the GFR signal with a Mexican Hat function. Experiment 1 consisted of a classic pseudorandomized presentation of object mass (light or heavy), where grip forces developed to lift a mass heavier than expected are known to exhibit corrective responses. For Experiment 2, we applied our two techniques to analyze grip force exerted for manipulating an inverted T-shaped object whose center of mass was changed across blocks of consecutive trials. For both experiments, subjects were asked to grasp the object at either predetermined or self-selected grasp locations ("constrained" and "unconstrained" task, respectively). Experiment 1 successfully validated the use of RMSE and CWT as they correctly distinguished trials with versus without force corrective responses. RMSE and CWT also revealed that grip force is characterized by more feedback-driven corrections when grasping at self-selected contact points. Future work will examine the application of our analytical approaches to a broader range of tasks, e.g., assessment of recovery of sensorimotor function following clinical intervention, interlimb

  18. Maximal intermittent handgrip strategy: design and evaluation of an exercise protocol and a grip tool.

    Science.gov (United States)

    Bentley, Danielle Christine; Thomas, Scott Gordon

    2016-01-01

    Handgrip (HG) exercise has been prescribed as a lifestyle intervention to successfully reduce resting blood pressure (BP) among heterogeneous groups of participants. Current HG protocols have limited accessibility due to complicated exercise prescriptions and sophisticated required equipment. Therefore, this research describes the design and evaluation of the maximal intermittent (MINT) HG exercise strategy, consisting of both a novel exercise protocol (32×5 seconds maximal grip squeezes separated by 5 seconds of rest between sets) and an original grip tool. This research was a multistep progressive design that included 51 postmenopausal women as participants in three separate research studies. Part 1 of this research focuses on the MINT exercise protocol. A literature-informed rationale for the design of the protocol is described. This includes exercise intensity, work-to-rest ratio, and total exercise duration with reference to the unique physiology (mechanoreflex and metaboreflex) of postmenopausal women. Subsequent experimental analyses of acute responses to the MINT protocol revealed that women produced 50% of their maximum grip force with moderate cardiovascular responses (increases of systolic BP: 41.6 mmHg, diastolic BP: 20.1 mmHg, heart rate: 35.1 bpm) that remained far below the thresholds of concern identified by the American College of Sports Medicine. Part 2 of this research describes the creation of a novel grip tool, beginning with a mixed-methods assessment of participant opinions regarding two distinct in-laboratory grip tools, leading to the creation of four prototype MINT tools. Structured focus groups revealed a strong preference for MINT prototype 1 for all tool design features, including color, shape, size, and foam grip. Collectively, the result of this multistep research is a novel HG exercise strategy with enhanced accessibility by being easy to understand and simple to execute. The long-term training effectiveness of MINT as an exercise

  19. Red-shouldered Hawk (Buteo lineatus) abundance and habitat in a reclaimed mine landscape

    Science.gov (United States)

    Balcerzak, M.J.; Wood, P.B.

    2003-01-01

    Fragmentation of the landscape by large-scale mining may affect Red-shouldered Hawk (Buteo lineatus) populations by reducing the amount of forested habitat available in a landscape and by creating fragmented forest parches surrounded by reclaimed mine lands. We examined habitat characteristics and relative abundance of Red-shouldered Hawks in reclaimed mine landscapes within four treatments: early-successional grassland habitat, mid-successional shrub/pole habitat, late-successional fragmented forest habitat, and late-successional intact forest habitat. We quantified microhabitat characteristics within an 11.3-m-radius plot centered on 156 vegetation plots throughout the four treatments. We surveyed 48 stations on and adjacent to three mines for Red-shouldered Hawks using standardized broadcast call techniques during February 2000-January 2001 and measured landscape characteristics within 1000-m buffer zones centered on each station from digitized aerial photographs. Mean abundance of Red-shouldered Hawks was significantly higher in the intact forest (x?? = 0.07 detections/ point, SE = 0.03) than the grassland (x?? = 0.01, SE = 0.01) treatment, but did not differ from the fragmented forest (x?? = 0.03, SE = 0.01) or shrub/pole (x?? = 0.03, SE = 0.01) treatments. Most microhabitat characteristics in both fragmented and intact forest differed from shrub/pole and grasslands. Amount of wetland was the most important characteristic determining presence of Red-shouldered Hawks in a forest-dominated landscape. More wetlands in the landscape may provide abundant amphibians and reptiles, which are important in the diet of Red-shouldered Hawks. ?? 2003 The Raptor Research Foundation, Inc.

  20. Buteo Nesting Ecology: Evaluating Nesting of Swainson’s Hawks in the Northern Great Plains

    Science.gov (United States)

    Inselman, Will M.; Datta, Shubham; Jenks, Jonathan A.; Jensen, Kent C.; Grovenburg, Troy W.

    2015-01-01

    Swainson’s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson’s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson’s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%–42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson’s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson’s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson’s hawks arriving to the breeding grounds. PMID:26327440

  1. Drag reduction by wing tip slots in a gliding Harris' hawk, Parabuteo unicinctus

    Science.gov (United States)

    Tucker

    1995-01-01

    The anterior-most primary feathers of many birds that soar over land bend upwards and separate vertically to form slotted wing tips during flight. The slots are thought to reduce aerodynamic drag, although drag reduction has never been demonstrated in living birds. Wing theory explains how the feathers that form the tip slots can reduce induced drag by spreading vorticity horizontally along the wing and by acting as winglets, which are used on aircraft to make wings non-planar and to spread vorticity vertically. This study uses the induced drag factor to measure the induced drag of a wing relative to that of a standard planar wing with the same span, lift and speed. An induced drag factor of less than 1 indicates that the wing is non-planar. The minimum drag of a Harris' hawk gliding freely in a wind tunnel was measured before and after removing the slots by clipping the tip feathers. The unclipped hawk had 70­90 % of the drag of the clipped hawk at speeds between 7.3 and 15.0 m s-1. At a wing span of 0.8 m, the unclipped hawk had a mean induced drag factor of 0.56, compared with the value of 1.10 assumed for the clipped hawk. A Monte Carlo simulation of error propagation and a sensitivity analysis to possible errors in measured and assumed values showed that the true mean value of the induced drag factor for the unclipped hawk was unlikely to be more than 0.93. These results for a living bird support the conclusions from a previous study of a feathered tip on a model wing in a wind tunnel: the feathers that form the slotted tips reduce induced drag by acting as winglets that make the wings non-planar and spread vorticity both horizontally and vertically.

  2. Corticomuscular coherence during hand gripping with DBS and medication in PD patients

    DEFF Research Database (Denmark)

    Sridharan, Kousik Sarathy; Højlund, Andreas; Johnsen, Erik Lisbjerg

    (MEG) from six PD patients performing hand gripping during DBS ON and medicated (levodopa, MED ON) conditions and from ten age-matched healthy controls. Participants performed isotonic contractions (hand gripping) with their right hand, and electromyography (EMG) was recorded from the extensor...... digitorum communis muscle with a belly-tendon montage. We calculated the mean-squared coherence between MEG and the rectified EMG signals. For each group and condition, we selected the maximum CMC value in the beta range (13-30 Hz) within the average of an a priori selection of nine left sensorimotor...

  3. Wear and Grip Loss Evaluation of High Chromium Welding Deposits Applied on Sugar Cane Rolls1

    OpenAIRE

    Diaz Millan, Sebastian; Rugbeño S.A.S; Aguilar Castro, Yesid; Escuela de Ingeniería de Materiales, Universidad del Valle, Cali, Colombia; Casanova García, Gonzalo Fernando; Escuela de Ingeniería Mecánica,Universidad del Valle, Cali, Colombia

    2015-01-01

    Wear on sugar cane rolls is an expensive maintenance problem for the sugar cane industry. Wear produces loss of sucrose extraction and loss of grip of the roll on the bagasse. This paper presents the evaluation of wear and loss of grip of hypoeutectic and hypereutectic high chromium welding deposits applied on ASTM A-36 steel and gray cast iron. A modified ASTM G-65 standard test was used. Wear was produced by the abrasive action of wet bagasse with three levels of mineral extraneous matter. ...

  4. The determination of the operating range of a twin-grip control yoke through biomechanical means

    Science.gov (United States)

    Gaertner, K. P.

    1978-01-01

    A twin-grip control yoke was designed as an ergonomic case study that allows dual axis control inputs, both axes being rotational. Inputs are effected by rotating the grips. How the handles were designed with respect to their shape and size and how the angular range of the control yoke in both rotational axes was evaluated. The control yoke which requires two-hand operation was tested to determine its operating range. The intention of this investigation was to find out the optimal form of the control yoke and the maximum permissible range in both rotating axes. In these experiments controls had no spring resistance.

  5. Analytical solutions in rotating linear dilaton black holes: Hawking radiation of charged massive scalar particles

    CERN Document Server

    Sakalli, I

    2016-01-01

    Hawking radiation of charged massive spin-0 particles are studied in the gravitational, electromagnetic, dilaton, and axion fields of rotating linear dilaton black holes. In this geometry, we separate the covariant Klein--Gordon equation into radial and angular parts and obtain the exact solutions of both the equations in terms of the confluent Heun functions. Using the radial solution, we analyze the behavior of the wave solutions near the event horizon of the rotating linear dilaton black hole and derive its Hawking radiation spectrum via the Damour--Ruffini--Sannan method.

  6. Hawking Radiation of Massive Vector Particles From Warped AdS$_{\\text{3}}$ Black Hole

    CERN Document Server

    Gursel, H

    2015-01-01

    Hawking radiation (HR) of massive vector particles from a rotating Warped Anti-de Sitter black hole in 2+1 dimensions (WAdS$_{\\text{3}}$BH) is studied in detail. The quantum tunneling approach with the Hamilton-Jacobi method (HJM) is applied in the Proca equation (PE), and we show that the radial function yields the tunneling rate of the outgoing particles. Comparing the result obtained with the Boltzmann factor, we satisfactorly reproduce the Hawking temperature (HT) of the WAdS$_{\\text{3}}$BH.

  7. A New Method to Study Hawking Radiation of Charged Particle from Stationary Axisymmetric Sen Black Hole

    Institute of Scientific and Technical Information of China (English)

    YANG Shu-Zheng; CHEN De-You

    2007-01-01

    @@ Taking the self-gravitation interaction and energy conservation, charge conservation and angular momentum conservation into account, we discuss the tunnelling characteristics of the charged particle from Sen black hole by the Hamilton-Jacobi method. The result shows that the tunnelling probability is related to the change of Bekenstein-Hawking entropy, and the actual radiation spectrum deviates from the pure thermal one, which is consistent with the result of Parikh and Wilczek and gives a new method to correct the Hawking pure thermal spectrum of Sen black hole.

  8. The Hawking radiation of the charged particle via tunnelling from the axisymmetric Sen black hole

    Institute of Scientific and Technical Information of China (English)

    Jiang Qing-Quan; Yang Shu-Zheng; Chen De-You

    2006-01-01

    Extending Parikh's semi-classical quantum tunnelling model, this paper has studied the Hawking radiation of the charged particle via tunnelling from the horizon of the axisymmetric Sen black hole. Different from the uncharged massless particle, the geodesies of the charged massive particle tunnelling from the horizon is not light-like. The derived result supports Parikh's opinion and provides a correct modification to Hawking strictly thermal spectrum developed by the fixed background space-time and not considering the energy conservation and the self-gravitation interaction.

  9. Open quantum system approach to the Gibbons-Hawking effect of de Sitter space-time.

    Science.gov (United States)

    Yu, Hongwei

    2011-02-11

    We analyze, in the paradigm of open quantum systems, the reduced dynamics of a freely falling two-level detector in de Sitter space-time in weak interaction with a reservoir of fluctuating quantized conformal scalar fields in the de Sitter-invariant vacuum. We find that the detector is asymptotically driven to a thermal state at the Gibbons-Hawking temperature, regardless of its initial state. Our discussion, therefore, shows that the Gibbons-Hawking effect of de Sitter space-time can be understood as a manifestation of thermalization phenomena that involves decoherence and dissipation in open quantum systems.

  10. Cavity Optical Pulse Extraction: ultra-short pulse generation as seeded Hawking radiation.

    Science.gov (United States)

    Eilenberger, Falk; Kabakova, Irina V; de Sterke, C Martijn; Eggleton, Benjamin J; Pertsch, Thomas

    2013-01-01

    We show that light trapped in an optical cavity can be extracted from that cavity in an ultrashort burst by means of a trigger pulse. We find a simple analytic description of this process and show that while the extracted pulse inherits its pulse length from that of the trigger pulse, its wavelength can be completely different. Cavity Optical Pulse Extraction is thus well suited for the development of ultrashort laser sources in new wavelength ranges. We discuss similarities between this process and the generation of Hawking radiation at the optical analogue of an event horizon with extremely high Hawking temperature. Our analytic predictions are confirmed by thorough numerical simulations.

  11. Integral method for the calculation of Hawking radiation in dispersive media. II. Asymmetric asymptotics.

    Science.gov (United States)

    Robertson, Scott

    2014-11-01

    Analog gravity experiments make feasible the realization of black hole space-times in a laboratory setting and the observational verification of Hawking radiation. Since such analog systems are typically dominated by dispersion, efficient techniques for calculating the predicted Hawking spectrum in the presence of strong dispersion are required. In the preceding paper, an integral method in Fourier space is proposed for stationary 1+1-dimensional backgrounds which are asymptotically symmetric. Here, this method is generalized to backgrounds which are different in the asymptotic regions to the left and right of the scattering region.

  12. Hawking radiation of charged Dirac particles in Vaidya-Bonner space-time

    Institute of Scientific and Technical Information of China (English)

    朱建阳; 张建华; 赵峥

    1995-01-01

    The dynamical properties of charged Dirac spinor particles in the Vaidya-Bonner space-time are investigated. The asymptotic solution to the radial part of the charged Dirac equation near the event horizon of the black hole is obtained. The Hawking temperature and the event horizon of the charged evaporating black hole, as well as the spectrum of the Hawking radiation of the Dirac particles, are exactly shown. Thereby, a new approach to the back-reaction of radiation from the non-stationary black holes is established.

  13. Correction to Hawking Radiation Characteristics of Stationary Demianski-Newman Black Hole

    Institute of Scientific and Technical Information of China (English)

    JIANG Qing-Quan; YANG Shu-Zheng

    2006-01-01

    The pure thermal spectrum in dragging coordinate system and the tunneling radiation characteristics across the event horizon for stationary Demianski-Newman black hole are researched. The result shows that the tunneling rate of the particle is relevant to Bekenstein-Hawking entropy, and the derived radiate spectrum is not strictly pure thermal,but is consistent with underlying unitary theory. Finally, we use the obtained results to reduce to stationary Kerr black hole and static Schwarzschild black hole, and find that only when ignoring the spectrum at higher energies is the tunneling radiation spectrum consistent with Hawking pure thermal one.

  14. Hawking Radiation of a Kaluza-Klein Black Hole Described by Landauer Transport Model

    Institute of Scientific and Technical Information of China (English)

    兰小刚; 韦联福

    2012-01-01

    We investigate the Hawking radiation of a Kaluza-Klein black hole by using one-dimensional(1D),non-equilibrium,Landauer transport model.The derived Hawking radiation temperature is in consistence with that obtained by using the usual anomaly method.With the Landauer transport model,we calculate the entropy flow out of the Kaluza-Klein black hole and the relevant entropy production rate.How these quantities depending on the physical parameters of the black hole is also discussed.

  15. Frenkelia sp.-like infection in the small intestine of a red-tailed hawk.

    Science.gov (United States)

    Lindsay, D S; Ambrus, S I; Blagburn, B L

    1987-10-01

    Developmental stages of a Frenkelia sp.-like coccidium were observed in tissue sections of the duodenum, jejunum, and ileum of a naturally infected red-tailed hawk (Buteo jamaicensis borealis) that died and was examined at necropsy. Developmental stages were located in the lamina propria of these tissues. Thirty sporulated sporocysts measured 11.1 X 8.1 microns in tissue sections. Four sporozoites were present in each sporulated sporocyst. The coccidial infection was not a contributing factor in the death of this red-tailed hawk.

  16. The loss of the entanglement between Hawking pairs due to a black hole singularity

    CERN Document Server

    Oshita, Naritaka

    2016-01-01

    We propose that the entanglement of Hawking pairs disappears due to redshift of the infalling mode in the vicinity of a black hole singularity. More concretely, the infalling mode is redshifted as it falls away from the horizon and decoheres, which makes the state of the Hawking pair separable, namely the entanglement is broken. This implies we no longer need to introduce the firewalls to avoid the firewall paradox. In other words, we do not need to abandon any of the fundamental principle, i.e., Einstein's equivalence principle, unitarity, and quantum field theory.

  17. Coordinates Used in Derivation of Hawking Radiation via Hamilton-Jacobi Method

    Science.gov (United States)

    Liu, Bo; He, Xiaokai; Liu, Wenbiao

    2009-05-01

    Coordinates used in derivation of Hawking radiation via Hamilton-Jacobi method are investigated more deeply. In the case of a 4-dimensional Schwarzschild black hole, a direct computation leads to a wrong result. In the meantime, making use of the isotropic coordinate or invariant radial distance, we can get the correct conclusion. More coordinates including Painleve and Eddington-Finkelstein are tried to calculate the semi-classical Hawking emission rate. The reason of the discrepancy between naive coordinate and well-behaved coordinates is also discussed.

  18. Tortoise Coordinates and Hawking Radiation in a Dynamical Spherically Symmetric Spacetime

    Institute of Scientific and Technical Information of China (English)

    YANG Jian; ZHAO Zheng; TIAN Gui-Hua; LIU Wen-Biao

    2009-01-01

    Hawking effect from dynamical spherical Vaidya black hole,Vaidya-Bonner black hole,and Vaidya-de Sitter black hole is investigated using the improved Damour-Ruffini method.After the new tortoise coordinate transformation in which the position τ of event horizon is an undetermined function and the temperature parameter κ is an undetermined constant,the Klein-Gordon equation can be written as the standard form at the event horizon,and both τ and κ can be determined automatically.Then extending the outgoing wave from outside to inside of the horizon analytically,the Hawking temperature can also be obtained automatically.

  19. Hawking radiation from the charged and magnetized BTZ black hole via covariant anomaly

    Institute of Scientific and Technical Information of China (English)

    Zeng Xiao-Xiong; Yang Shu-Zheng

    2009-01-01

    This paper discusses Hawking radiation from the charged and magnetized Bafiados-Teitelboim-Zanelli (BTZ) black hole from the viewpoint of anomaly, initiated by Robinson and Wilczek recently. It reconstructs the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge and gauge potential. It employs the covariant anomaly cancellation method to determine thecompensating fluxes of charge flow and energy-momentum tensor, which are shown to match with those of the 2- dimensional blackbody radiation at the Hawking temperature exactly.

  20. Remarks on Hawking radiation as tunneling from a uniformly accelerating black hole

    Indian Academy of Sciences (India)

    Xiao-Xiong Zeng; Jian-Song Hou; Shu-Zheng Yang

    2008-03-01

    Motivated by the Hamilton-Jacobi method of Angheben et al, we investigate the Hawking tunneling radiation from a uniformly accelerating rectilinear black hole for which the horizons and entropy are functions of . After several coordinate transformations, we conclude that when the self-gravitational interaction and energy conservation are taken into account, the actual radiation spectrum deviates from the thermal one and the tunneling rate is the function of though it is still related to the change of the Bekenstein-Hawking entropy.

  1. Grip strength and lower limb extension power in 19-72-year-old Danish men and women

    DEFF Research Database (Denmark)

    Aadahl, Mette; Beyer, Nina; Linneberg, Allan

    2011-01-01

    To assess muscular fitness by hand grip strength (HGS) and lower limb extension power (LEP) and to explore associations with age, leisure time physical activity (LTPA) and body composition.......To assess muscular fitness by hand grip strength (HGS) and lower limb extension power (LEP) and to explore associations with age, leisure time physical activity (LTPA) and body composition....

  2. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness

    DEFF Research Database (Denmark)

    Willems, Sara M; Wright, Daniel J.; Day, Felix R

    2017-01-01

    Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 1...

  3. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness

    NARCIS (Netherlands)

    Willems, Sara M.; Wright, D.J.; Day, Felix R.; Trajanoska, Katerina; Joshi, P.K.; Morris, John A.; Matteini, Amy M.; Garton, Fleur C.; Grarup, Niels; Oskolkov, Nikolay; Thalamuthu, Anbupalam; Mangino, Massimo; Liu, Jun; Demirkan, Ayse; Lek, Monkol; Xu, Liwen; Wang, Guan; Oldmeadow, Christopher; Gaulton, Kyle J.; Lotta, Luca A.; Miyamoto-Mikami, Eri; Rivas, Manuel A.; White, Tom; Loh, Po Ru; Aadahl, Mette; Amin, Najaf; Attia, John R.; Austin, Krista; Benyamin, Beben; Brage, Søren; Cheng, Yu Ching; Ciȩszczyk, Paweł; Derave, Wim; Eriksson, Karl Fredrik; Eynon, Nir; Linneberg, Allan; Lucia, Alejandro; Massidda, Myosotis; Mitchell, Braxton D.; Miyachi, Motohiko; Murakami, Haruka; Padmanabhan, Sandosh; Pandey, Ashutosh; Papadimitriou, Ioannis; Rajpal, Deepak K.; Sale, Craig; Schnurr, Theresia M.; Sessa, Francesco; Shrine, Nick; Tobin, Martin D.; Varley, Ian; Wain, Louise V.; Wray, Naomi R.; Lindgren, Cecilia M.; MacArthur, Daniel G.; Waterworth, Dawn M.; McCarthy, Mark I.; Pedersen, Oluf; Khaw, Kay Tee; Kiel, Douglas P.; Pitsiladis, Yannis; Fuku, Noriyuki; Franks, Paul W.; North, Kathryn N.; Duijn, Van C.M.; Mather, Karen A.; Hansen, Torben; Hansson, Ola; Spector, Tim D.; Murabito, Joanne M.; Richards, J.B.; Rivadeneira, Fernando; Langenberg, Claudia; Perry, John R.B.; Wareham, Nick J.; Scott, Robert A.; Oei, Ling; Zheng, Hou Feng; Forgetta, Vincenzo; Leong, Aaron; Ahmad, Omar S.; Laurin, Charles; Mokry, Lauren E.; Ross, Stephanie; Elks, Cathy E.; Bowden, Jack; Warrington, Nicole M.; Murray, Anna; Ruth, Katherine S.; Tsilidis, Konstantinos K.; Medina-Gómez, Carolina; Estrada, Karol; Bis, Joshua C.; Chasman, Daniel I.; Demissie, Serkalem; Enneman, Anke W.; Hsu, Yi Hsiang; Ingvarsson, Thorvaldur; Kähönen, Mika; Kammerer, Candace; Lacroix, Andrea Z.; Li, Guo; Liu, Ching Ti; Liu, Yongmei; Lorentzon, Mattias; Mägi, Reedik; Mihailov, Evelin; Milani, Lili; Moayyeri, Alireza; Nielson, Carrie M.; Sham, Pack Chung; Siggeirsdotir, Kristin; Sigurdsson, Gunnar; Stefansson, Kari; Trompet, Stella; Thorleifsson, Gudmar; Vandenput, Liesbeth; Velde, Van Der Nathalie; Viikari, Jorma; Xiao, Su Mei; Zhao, Jing Hua; Evans, Daniel S.; Cummings, Steven R.; Cauley, Jane; Duncan, Emma L.; Groot, De Lisette C.P.G.M.; Esko, Tonu; Gudnason, Vilmundar; Harris, Tamara B.; Jackson, Rebecca D.; Jukema, J.W.; Ikram, Arfan M.A.; Karasik, David; Kaptoge, Stephen; Kung, Annie Wai Chee; Lehtimäki, Terho; Lyytikäinen, Leo Pekka; Lips, Paul; Luben, Robert; Metspalu, Andres; Meurs, van Joyce B.; Minster, Ryan L.; Orwoll, Erick; Oei, Edwin; Psaty, Bruce M.; Raitakari, Olli T.; Ralston, Stuart W.; Ridker, Paul M.; Robbins, John A.; Smith, Albert V.; Styrkarsdottir, Unnur; Tranah, Gregory J.; Thorstensdottir, Unnur; Uitterlinden, Andre G.; Zmuda, Joseph; Zillikens, M.C.; Ntzani, Evangelia E.; Evangelou, Evangelos; Ioannidis, John P.A.; Evans, David M.; Ohlsson, Claes

    2017-01-01

    Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,

  4. Relationship between grip, pinch strengths and anthropometric variables, types of pitch throwing among Japanese high school baseball pitchers.

    Science.gov (United States)

    Tajika, Tsuyoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shitara, Hitoshi; Ichinose, Tsuyoshi; Shimoyama, Daisuke; Okura, Chisa; Kanazawa, Saeko; Nagai, Ayako; Takagishi, Kenji

    2015-03-01

    Grip and pinch strength are crucially important attributes and standard parameters related to the functional integrity of the hand. It seems significant to investigate normative data for grip and pinch strength of baseball players to evaluate their performance and condition. Nevertheless, few reports have explained the association between grip and pinch strength and anthropometric variables and types of pitch throwing for baseball pitchers. The aim of this study was to measure and evaluate clinical normative data for grip and tip, key, palmar pinch strength and to assess the relationship between these data and anthropometric variables and types of pitch throwing among Japanese high-school baseball pitchers. One hundred-thirty three healthy high school baseball pitchers were examined and had completed a self-administered questionnaire including items related to age, hand dominance, throwing ratio of type of pitch. A digital dynamometer was used to measure grip strength and a pinch gauge to measure tip, key and palmer pinch in both dominant and nondominant side. Body composition was measured by the multi frequency segmental body composition analyzer. Grip strength and tip and palmer pinch strength in dominant side were statistically greater than them in nondominant side (P types of pitches thrown and grip strength and tip, key, palmar pinch strength. Our result provides normative values and evidences for grip and pinch strengths in high school baseball pitchers.

  5. Age trajectories of grip strength: cross-sectional and longitudinal data among 8,342 Danes aged 46 to 102

    DEFF Research Database (Denmark)

    Frederiksen, Henrik; Hjelmborg, Jacob; Mortensen, Jakob

    2006-01-01

    with increasing age. Estimates were obtained by using full-information methods from large population-representative studies. Equations of expected grip strength, as well as tables with sex-, age-, and height-stratified reference data, provide an opportunity to include grip-strength measurement in clinical care...

  6. An investigation of the association between grip strength and hip and knee joint moments in older adults.

    Science.gov (United States)

    Samuel, Dinesh; Rowe, Philip

    2012-01-01

    Grip strength is a predictor of health outcomes but with differing rates of age-related decline in muscle strength, it is unclear whether handgrip is a reliable indicator of lower limb moments. This study investigated the relationship between grip strength and lower extremity moments in community-dwelling older adults. Eighty-two healthy volunteers aged 60-82 years (mean age 73.2 years) performed maximal voluntary contractions of knee and hip extensors and flexors at three positions and at neutral position for hip abductors and adductors using a custom-built dynamometer. Grip strength was measured using an electronic Jamar dynamometer. The relative reduction in muscle strength of 80s age category compared to 60-year-olds ranged from 14% for grip strength to 27% for hip abductors. Peak torque of flexors and extensors of the knee and hip joints were significantly correlated with grip strength and Pearson's correlation coefficients ranged from 0.56 to 0.78 with the highest correlations observed between knee moments and grip strength. "Good" correlation was found but only 31-60% of the variation in grip strength could be related to changes in joint torques. Hence the assumption that grip strength is an indicator of strength in the lower limb would seem unjustified in the healthy older adult.

  7. The cost-effectiveness of grip on challenging behaviour: an economic evaluation of a care programme for managing challenging behaviour

    NARCIS (Netherlands)

    Zwijsen, S.A.; Bosmans, J.E.; Gerritsen, D.L.; Pot, A.M.; Hertogh, C.M.; Smalbrugge, M.

    2016-01-01

    OBJECTIVE: The objective of the study was to evaluate the cost-effectiveness of implementing the Grip on Challenging Behaviour care programme (GRIP) on dementia special care units in comparison with usual care. METHODS: A stepped wedge design was used. Challenging behaviour and quality of life were

  8. Does grip strength on the unaffected side of patients with hemiparetic stroke reflect the strength of other ipsilateral muscles?

    Science.gov (United States)

    Takahashi, Jumpei; Nishiyama, Toru; Matsushima, Yoshimasa

    2017-01-01

    [Purpose] Grip strength is used as an indicator of overall body muscular strength. However, most studies on grip strength have been performed in healthy people, and no study has evaluated it in the unaffected side of patients with hemiparetic stroke. The purpose of this study was to determine if grip strength on the unaffected side of patients with hemiparetic stroke correlates with the strength of other ipsilateral musculature. [Subjects and Methods] The maximal strengths of the muscles on the unaffected side of 31 patients with hemiparetic stroke were measured, and correlation coefficients were calculated. [Results] The results revealed significant positive correlations between grip strength on the unaffected side and the strength of the other ipsilateral muscle groups, with relatively high correlations being observed for the upper extremity muscle groups. [Conclusion] This suggests that grip strength on the unaffected side of patients with hemiparetic stroke can be used as a simple way to estimate overall strength on that side.

  9. Differential roles for NSF and GRIP/ABP in AMPA receptor cycling.

    Science.gov (United States)

    Braithwaite, Steven P; Xia, Houhui; Malenka, Robert C

    2002-05-14

    alpha-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) stability and movement at synapses are important factors controlling synaptic strength. Here, we study the roles of proteins [N-ethylmaleimide-sensitive fusion protein (NSF), glutamate receptor AMPAR binding protein (ABP)-interacting protein (GRIP)/(ABP), and protein interacting with C-kinase-1 (PICK1) that interact with the GluR2 subunit in the control of the surface expression and cycling of AMPARs. Epitope-tagged GluR2 formed functional receptors that exhibited targeting to synaptic sites. Constructs in which binding to NSF, PDZ proteins (GRIP/ABP and PICK1), or GRIP/ABP alone was eliminated each exhibited normal surface targeting and constitutive cycling. The lack of NSF binding, however, resulted in receptors that were endocytosed to a greater extent than wild-type receptors in response to application of AMPA or N-methyl-d-aspartate (NMDA). Conversely, the behavior of the GluR2 mutants incapable of binding to GRIP/ABP suggests that these PDZ proteins play a role in the stabilization of an intracellular pool of AMPARs that have been internalized on stimulation, thus inhibiting their recycling to the synaptic membrane. These results provide further evidence for distinct functional roles of GluR2-interacting proteins in AMPAR trafficking.

  10. Weight-specific anticipatory coding of grip force in human dorsal premotor cortex

    DEFF Research Database (Denmark)

    van Nuenen, Bart F L; Kuhtz-Buschbeck, Johann; Schulz, Christian

    2012-01-01

    ). An additional pre-cue (S1) correctly predicted the weight in 75% of the trials. Participants were asked to use this prior information to prepare for the lift. In the sham condition, grip force showed a consistent undershoot, if the S1 incorrectly prompted the preparation of a light lift. Likewise, an S1...

  11. Eyes, Grip and Gesture as Objective Indicators of Intentions and Attention

    DEFF Research Database (Denmark)

    Mortensen, Ditte Hvas

    This poster abstract presents the first part of a study concerning the use of information about gaze, grip and gesture to create non-command interaction. The experiment reported here seeks to establish the occurrence of patterns in nonverbal communication,  which may be used in an activity aware...

  12. Facilitation of corticospinal tract excitability by transcranial direct current stimulation combined with voluntary grip exercise.

    Science.gov (United States)

    Kim, Gi-Wook; Ko, Myoung-Hwan

    2013-08-26

    Previous studies have established that transcranial direct current stimulation (tDCS) is a powerful technique for the deliberate manipulation of the activity of human cerebral cortex. Moreover, it has also been shown that the non-exhausted voluntary motor exercise increases the excitability of corticospinal tract. We conducted this study to define the facilitation effect following anodal tDCS combined with the voluntary grip exercise as compared with single use of tDCS or voluntary grip exercise. Our result showed that the combination of anodal tDCS with voluntary grip exercise produced a 2-fold increase in the amplitude of MEP as compared with single use of anodal tDCS or voluntary grip exercise. In conclusion, our result could indicate that the treatment outcomes of brain and neurorehabilitation using tDCS would be better when tDCS is combined with the appropriate method of voluntary exercise as compared with single use of tDCS. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Grip Force Control Is Dependent on Task Constraints in Children with and without Developmental Coordination Disorder

    Science.gov (United States)

    Law, Sui-Heung; Lo, Sing Kai; Chow, Susanna; Cheing, Gladys L.Y.

    2011-01-01

    Excessive grip force (GF) is often found in children with developmental coordination disorder (DCD). However, their GF control may vary when task constraints are imposed upon their motor performance. This study aimed to investigate how their GF control changes in response to task demands, and to examine their tactile sensitivity. Twenty-one…

  14. EFFECT OF ECCENTRIC EXERCISE PROGRAMME ON PAIN AND GRIP STRENGTH FOR SUBJECTS WITH MEDIAL EPICONDYLITIS

    Directory of Open Access Journals (Sweden)

    Mishra Prashant Akhilesh

    2014-04-01

    Full Text Available Background and Objective: Therapeutic eccentric exercise may provide both a structural and functional benefit during tendinopathy rehabilitation. The objective is to find the effect of eccentric exercises on improvement of pain and grip strength for subjects with Medial Epicondylitis. Method: Pre to post test experimental study design randomized thirty subjects with medial epicondylitis, 15 each into Group A and Group B. Group B subjects were treated with conventional therapy and Eccentric exercises. Group A subjects were treated with conventional therapy. Results: When means of post intervention were compared using Independent ‘t’ between groups there was no statistically significant difference in improvements obtained in VAS scores and grip strength. There was a statistically significant change in means of VAS score and Grip strength when means were analyzed by using Paired‘t’ test and Wilcoxon signed rank test within the groups with positive percentage of change. Conclusion: It is concluded that four weeks of Eccentric Exercise Programme combined with conventional therapy shown significant effect on improving pain and Grip strength, however the improvement obtained has no difference when compared with control conventional treatment for Subjects with Medial Epicondylitis.

  15. The effect of precision and power grips on activations in human auditory cortex

    Directory of Open Access Journals (Sweden)

    Patrik Alexander Wikman

    2015-10-01

    Full Text Available The neuroanatomical pathways interconnecting auditory and motor cortices play a key role in current models of human auditory cortex (AC. Evidently, auditory-motor interaction is important in speech and music production, but the significance of these cortical pathways in other auditory processing is not well known. We investigated the general effects of motor responding on AC activations to sounds during auditory and visual tasks. During all task blocks, subjects detected targets in the designated modality, reported the relative number of targets at the end of the block, and ignored the stimuli presented in the opposite modality. In each block, they were also instructed to respond to targets either using a precision grip, power grip, or to give no overt target responses. We found that motor responding strongly modulated AC activations. First, during both visual and auditory tasks, activations in widespread regions of AC decreased when subjects made precision and power grip responses to targets. Second, activations in AC were modulated by grip type during the auditory but not during the visual task. Further, the motor effects were distinct from the strong attention-related modulations in AC. These results are consistent with the idea that operations in AC are shaped by its connections with motor cortical regions.

  16. Precision grip in congenital and acquired hemiparesis: similarities in impairments and implications for neurorehabilitation - review

    Directory of Open Access Journals (Sweden)

    Yannick eBleyenheuft

    2014-06-01

    Full Text Available Background: Patients with congenital and acquired hemiparesis incur long-term functional deficits, among which the loss of prehension that may impact their functional independence. Identifying, understanding and comparing the underlying mechanisms of prehension impairments represent an opportunity to better adapt neurorehabilitationObjective: The present review aims to provide a better understanding of precision grip deficits in congenital and acquired hemiparesis and to determine whether the severity and type of fine motor control impairments depend on whether or not the lesions are congenital or acquired in adulthood. Methods: Using combinations of the following key words: fingertip force, grip force, precision grip, cerebral palsy, stroke, pubmed and Scopus databases were used to search studies from 1984 to 2013. Results: Individuals with both congenital and acquired hemiparesis were able to some extent to use anticipatory motor control in precision grip tasks, even if this control was impaired in the paretic hand. In both congenital or acquired hemiparesis, the ability to plan efficient anticipatory motor control when the less-affected hand is used provides a possibility to remediate impairments in anticipatory motor control of the paretic hand. Conclusion: Surprisingly we observed very few differences between the results of studies in children with congenital hemiplegia and stroke patients. We suggest that the underlying specific strategies of neurorehabilitation developed for each one could benefit the other.

  17. Getting a grip on numbers : Numerical magnitude priming in object grasping

    NARCIS (Netherlands)

    Lindemann, Oliver; Abolafia, Juan A.; Girardi, Giovanna; Bekkering, Harold

    2007-01-01

    To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small

  18. Frimand Needle Holder Reduces Suturing Time and Surgical Stress When Suturing in Palm Grip.

    Science.gov (United States)

    Frimand Rönnow, Carl-Fredrik; Jeppsson, Bengt; Thorlacius, Henrik

    2016-06-01

    Purpose The Frimand needle holder (FNH) was developed to facilitate palm grip suturing. In the present study, we wanted to examine the impact of the FNH compared with a conventional Hegar-styled needle holder (HSNH) on suture time and surgical stress. Methods Thirty-two surgeons were enrolled and they performed sets of 3 continuous sutures on a polyurethane pad with premarked insert and exit points and the time for suturing was measured. Surgical stress was quantified by having the surgeons to perform 10 release maneuvers with the FNH and the HSNH on a needle attached to a scale. The scale sent 5 values per second to a computer. The first measurement of each series was regarded as the starting weight and all subsequent measurements were either regarded as neutral, pressure or traction. The sum of these measurements represented total surgical stress. Results We found that all surgeons reduced their median suturing time by 16% when using FNH for palm grip suturing with no difference between junior and senior surgeons. Moreover, it was observed that FNH decreased median surgical stress by 62% for all surgeons performing palm grip suturing compared with a conventional HSNH. Conclusion We conclude that the FNH reduces suture time and surgical stress compared with HSNH when performing palm grip suturing. These findings warrant studies in surgical patients in order to evaluate the potential clinical impact of FNH.

  19. First flight of the Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) instrument

    CERN Document Server

    Duncan, Nicole; Shih, A Y; Hurford, G J; Bain, H M; Amman, M; Mochizuki, B A; Hoberman, J; Olson, J; Maruca, B A; Godbole, N M; Smith, D M; Sample, J; Kelley, N A; Zoglauer, A; Caspi, A; Kaufmann, P; Boggs, S; Lin, R P

    2016-01-01

    The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) is a balloon-borne telescope designed to study solar-flare particle acceleration and transport. We describe GRIPS's first Antarctic long-duration flight in Jan 2016 and report preliminary calibration and science results. Electron and ion dynamics, particle abundances and the ambient plasma conditions in solar flares can be understood by examining hard X-ray (HXR) and gamma-ray emission (20 keV to 10 MeV) with enhanced imaging, spectroscopy and polarimetry. GRIPS is specifically designed to answer questions including: What causes the spatial separation between energetic electrons producing HXRs and energetic ions producing gamma-ray lines? How anisotropic are the relativistic electrons, and why can they dominate in the corona? How do the compositions of accelerated and ambient material vary with space and time, and why? GRIPS's key technological improvements over the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) include 3D position-sensi...

  20. Grip Strength as a Marker of Hypertension and Diabetes in Healthy Weight Adults.

    Science.gov (United States)

    Mainous, Arch G; Tanner, Rebecca J; Anton, Stephen D; Jo, Ara

    2015-12-01

    Muscle strength may play a role in cardiometabolic disease. We examined the relationship between hand grip strength and diabetes and hypertension in a sample of healthy weight adults. In 2015, we analyzed the National Health and Nutrition Examination Survey 2011-2012 for adults aged ≥20 years with healthy BMIs (between 18.5 and Hypertension was based on measured blood pressure and reported hypertension diagnosis. Individuals with undiagnosed diabetes compared with individuals without diabetes had lower grip strength (51.9 vs 69.8, p=0.0001), as did individuals with diagnosed diabetes compared with individuals without diabetes (61.7 vs 69.8, p=0.008). Mean grip strength was lower among individuals with undiagnosed hypertension compared with individuals without hypertension (63.5 vs 71.5, p=0.008) as well as among individuals with diagnosed hypertension compared with those without hypertension (60.8 vs 71.5, phypertension (β=-6.6, p=0.004) and diagnosed hypertension (β=-4.27, p=0.04) compared with individuals without hypertension. Among healthy weight adults, combined grip strength is lower in individuals with diagnosed and undiagnosed diabetes and hypertension. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Measurement error in grip and pinch force measurements in patients with hand injuries.

    Science.gov (United States)

    Schreuders, Ton A R; Roebroeck, Marij E; Goumans, Janine; van Nieuwenhuijzen, Johan F; Stijnen, Theo H; Stam, Henk J

    2003-09-01

    There is limited documentation of measurement error of grip and pinch force evaluation methods. The purposes of this study were (1) to determine indexes of measurement error for intraexaminer and interexaminer measurements of grip and pinch force in patients with hand injuries and (2) to investigate whether the measurement error differs between measurements of the injured and noninjured hands and between experienced and inexperienced examiners. The subjects were a consecutive sample of 33 patients with hand injuries who were seen in the Department of Rehabilitation Medicine of Erasmus MC-University Medical Center Rotterdam in the Netherlands. Repeated measurements were taken of grip and pinch force, with a short break of 2 to 3 minutes between sessions. For the grip force in 2 handle positions (distance between handles of 4.6 and 7.2 cm, respectively), tip pinch (with the index finger on top and the thumb below, with the other fingers flexed) and key pinch force (with the thumb on top and the radial side of the index finger below) data were obtained on both hands of the subjects by an experienced examiner and an inexperienced examiner. Intraclass correlation coefficients (ICCs), standard errors of measurement (SEMs), and associated smallest detectable differences (SDDs) were calculated and compared with data from previous studies. The reliability of the measurements was expressed by ICCs between .82 and .97. For grip force measurements (in the second handle position) by the experienced examiner, an SDD of 61 N was found. For tip pinch and key pinch, these values were 12 N and 11 N, respectively. For measurements by the inexperienced examiner, SDDs of 56 N for grip force and 13 N and 18 N for tip pinch and key pinch were found. Based on the SEMs and SDDs, in individual patients only relatively large differences in grip and pinch force measurements can be adequately detected between consecutive measurements. Measurement error did not differ between injured and

  2. Addendum: Hawking Radiation of Photons in a Variable-mass Kerr Black Hole

    OpenAIRE

    S. Q. Wu; Cai, X

    2001-01-01

    Hawking evaporation of photons in a variable-mass Kerr space-time is investigated by using a method of the generalized tortoise coordinate transformation. The blackbody radiant spectrum of photons displays a new spin-rotation coupling effect obviously dependent on different helicity states of photons.

  3. Behavioural ecology, distribution and conservation of the Javan Hawk-eagle Spizaetus bartelsi Stresemann, 1924

    NARCIS (Netherlands)

    Sözer, Resit; Nijman, Vincent

    1995-01-01

    In the period December 1993 – January 1995 research on the behavioural ecology, distribution and conservation of the Javan Hawk-eagle Spizaetus bartelsi was carried out by R. Sözer and V. Nijman, under supervision of BirdLife International / PHPA – Indonesia Programme. This research was part of the

  4. Energy shift of H-atom electrons due to Gibbons-Hawking thermal bath

    CERN Document Server

    Pardy, Miroslav

    2016-01-01

    The electromagnetic shift of energy levels of H-atom electrons is determined by calculating an electron coupling to the Gibbons-Hawking electromagnetic field thermal bath. Energy shift of electrons in H-atom is determined in the framework of the non-relativistic quantum mechanics.

  5. Non-Thermal Corrections to Hawking Radiation Versus the Information Paradox

    CERN Document Server

    Dvali, Gia

    2015-01-01

    We provide a model-independent argument indicating that for a black hole of entropy N the non-thermal deviations from Hawking radiation, per each emission time, are of order 1/N, as opposed to exp(-N). This fact abolishes the standard a priory basis for the information paradox.

  6. Gravitational instantons of type $D_k$ and a generalization of the Gibbons-Hawking Ansatz

    CERN Document Server

    Ionas, Radu A

    2016-01-01

    We describe a quaternionic-based Ansatz generalizing the Gibbons-Hawking Ansatz to a class of hyperk\\"ahler metrics with hidden symmetries. We then apply it to obtain explicit expressions for gravitational instanton metrics of type $D_k$.

  7. Dynamics of the echolocation beam during prey pursuit in aerial hawking bats

    DEFF Research Database (Denmark)

    Jakobsen, Lasse; Olsen, Mads Nedergaard; Surlykke, Annemarie

    2015-01-01

    " than the vespertilionids, but ensonifying objects far ahead suggesting more clutter. Thus, beam broadening is not a fundamental property of the echolocation system. However, based on the results, we hypothesize that increased peripheral detection is crucial to all aerial hawking bats in the final...

  8. Hawking Radiation of Dirac Particles on Rindler Horizon to a Uniformly Accelerating Observer

    Institute of Scientific and Technical Information of China (English)

    ZHANGJinK-Yi

    2003-01-01

    Following the method of Damour and Ruffini, the Hawking radiation of Dirac particles on Rindler horison to a uniformly accelerating observer is studied this paper. The temperature on Rindler horizon surface and the thermal spectrum formula of Dirac particles are obtained. The result is discussed.

  9. Hawking Radiation of Dirac Particles on Rindler Horizon to a Uniformly Accelerating Observer

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jing-Yi

    2003-01-01

    Following the method of Damour and Ruffini, the Hawking radiation of Dirac particles on Rindler horizonto a uniformly accelerating observer is studied in this paper. The temperature on Rindler horizon surface and the thermalspectrum formula of Dirac particles are obtained. The result is discussed.

  10. Back reaction, the Hawking emission spectrum from the charged black hole

    Energy Technology Data Exchange (ETDEWEB)

    Xu Pingchuan; Wang Zhihong [Institute of Theoretical Physics, China West Normal University, Nanchong, Sichuan 637002 (China); Han Yan, E-mail: pcxu@163.com [College of Mathematic and Information, China West Normal University, Nanchong, Sichuan 637002 (China)

    2011-06-21

    The Hawking emission spectrum of the Schwarzschild-like black hole has been successfully described in the tunneling picture. In this paper, we develop the idea for the case of the charged black hole with back reaction. First, the most general, static spherically symmetric charged black hole, in the presence of back reaction, has been provided by solving the Einstein equations with a non-zero vacuum expectation value of the energy-momentum tensor (T{sub {mu}{nu}}({phi}, g{sub {mu}{nu}})). At the one-loop corrections, we also produce the modified expressions for the Hawking temperature and Bekenstein-Hawking entropy. It is found that the leading correction to the semiclassical entropy is logarithmic and next to the leading order is inverse of the horizon area, just as the expected well-known results. In particular, as our main focus in this paper, we show that the modified black hole still radiates with a perfect blackbody spectrum, only the temperature undergoing quantum corrections. Also, the Hawking fluxes of the electric current and energy-momentum tensor to include the effect of back reaction are obtained. The results are interestingly found sharing the same form as that from the point of anomaly.

  11. Organophosphate insecticide (famphur) topically applied to cattle kills magpies and hawks

    Science.gov (United States)

    Henny, C.J.; Blus, L.J.; Kolbe, E.J.; Fitzner, R.E.

    1985-01-01

    A systematic field study of a black-billed magpie (P. pica) population revealed that magpies and red-tailed hawks (B. jamaicensis) were killed by famphur (= famophos, Warbex) used as a pour-on to control cattle warbles (Hypoderma sp.). Magpie mortality began on treatment day and continued for more than 3 mo. (38 found death); mortality peaked between Day 5 an Day 13. Estimates of magpie density (based on transects) decreased in both the control and treatment areas, but the decrease was greater in the treatment area. A red-tailed hawk found dead on Day 10 had eaten a famphur-contaminated magpie. Another red-tailed hawk was found alive but immobilized, and a 3rd died outside the study area. Brain cholinesterse (ChE) activity was 70-92% depressed in all dead birds examined; famphur residues were detected in all 17 magpies and the 2 hawks analyzed. The amount of famphur obtained by the dead magpies was estimated at 5.2-6.1 mg/kg (based on residue concentrations in the gizzard), which was above the acute oral LD50 for several bird species. The cow hair portion (12%) of the pooled gizzard contents from 13 other dead magpies produced extremely high famphur residues (4600 ppm). The residues persisted on cattle hair for more than 90 days post-treatment. Magpie populations in the far western states declined between 1968 and 1979, which corresponds with widespread use of famphur, although other factors may be involved.

  12. Decreases in a Population of Red-Shouldered Hawks Nesting in Central Maryland

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This outlines the results of a 32 year nesting study of the Red-shouldered Hawk in central Maryland that adds 31 years of observations to an earlier long-term study....

  13. HawkEye: CubeSat SeaWiFS update

    Science.gov (United States)

    Schueler, Carl; Holmes, Alan

    2016-09-01

    The SeaHawk 3U CubeSat program is funded by the Gordon and Betty Moore Foundation of San Francisco, and managed by John Morrison of the University of North Carolina-Wilmington (UNC-W). Cloudland Instruments is developing HawkEye for SeaHawk. HawkEye is a multispectral ocean color imager of SeaWiFS quality with 120 meter nadir resolution from an orbit altitude of 540 km to provide observation of sub-mesoscale variability for insights into poorly understood mixing dynamics. 120 meter imagery improves ability, relative to SeaWiFS 1km resolution, to monitor fjords, estuaries, coral reefs and other near-shore environments where anthropogenic stresses are often most acute and where there are considerable security and commercial interests. The optics, filters, and arrays comprise a cube 10 cm on a side to fit a 3U CubeSat manufactured by ClydeSpace of Glasgow Scotland, and provide a 350 km swath cross-track.

  14. Evaluating the release of a large store from the BAE Hawk Mk120

    CSIR Research Space (South Africa)

    Jamison, Kevin

    2010-11-01

    Full Text Available The analysis of the release of a large store from the outboard pylon of the BAE Hawk Mk120 is described as a case study. The process adopted to address this challenge included using both the ARUV panel code and the CFD-FASTRAN Navier...

  15. Hawking radiation from Kerr-Newman-Kasuya black hole via quantum anomalies

    Institute of Scientific and Technical Information of China (English)

    He Tang-Mei; Fan Jun-Hui; Wang Yong-Jiu

    2008-01-01

    We have studied the Hawking radiation of the Kerr-Newman-Kasuya black hole via gauge and gravitational anomaly in the dragging coordinates. The fluxes of the electromagnetic current and the energy momentum tensor for each partial wave in two-dimensional field are obtained.

  16. 75 FR 6625 - Dixie National Forest, UT, Kitty Hawk Administrative Site Master Development Plan

    Science.gov (United States)

    2010-02-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Forest Service Dixie National Forest, UT, Kitty Hawk Administrative Site Master Development Plan AGENCY: Forest Service, USDA. ACTION: Notice of Intent to Prepare an Environmental Impact Statement. SUMMARY:...

  17. Are red-tailed hawks and great horned owls diurnal-nocturnal dietary counterparts?

    Science.gov (United States)

    Marti, C.D.; Kochert, Michael N.

    1995-01-01

    Red-tailed Hawks (Buteo jamaicensis) and Great Homed Owls (Bubo virginianus)are common in North America where they occupy a wide range of habitats, often sympatrically. The two species are similar in size and have been portrayed as ecological counterparts, eating the same prey by day and night. We tested the trophic similarity of the two species by comparing published dietary data from across the United States. Both species ate primarily mammals and birds, and mean proportions of those two prey types did not differ significantly between diets of the two raptors. Red-tailed Hawks ate significantly more reptiles, and Great Homed Owls significantly more invertebrates. Dietary diversity was not significantly different at the level of prey taxonomic class, and diet overlap between the two species averaged 91%. At the prey species level, dietary overlap averaged only 50%, and at that level Red-tailed Hawk dietary diversity was significantly greater than that of Great Horned Owls. Mean prey mass of Red-tailed Hawks was significantly greater than that of Great Homed Owls. Populations of the two species in the western United States differed trophically more than did eastern populations. We conclude that, although the two species are generalist predators, they take largely different prey species in the same localities resulting in distinctive trophic characteristics.

  18. Street hawking among in-school adolescents in a south-western town in Nigeria: pattern, determinants and effects on school performance.

    Science.gov (United States)

    Ijadunola, Macellina Y; Ojo, Temitope O; Babatunde, Adelekan; Olatunji, Gbajumo J; Owolabi, Gbolagade K; Adewale, Ibiyemi A; Ifedayo, Ibukun F; Friday, Ijuewe S

    2015-02-01

    Street hawking is the commonest form of child labor in Nigeria. Although street hawking is very pervasive, there is the increasing need to fully understand its pattern and effects on those involved in hawking particularly adolescents who combine schooling with hawking. In Nigeria, data on the effects of street hawking on in-school adolescents are generally scanty. Therefore, the present study was undertaken in Ife Central Local Government Area (LGA) of Osun State, Nigeria to assess the pattern, determinants of street hawking among in-school adolescents and its effect on school performance. A cross-sectional study of 435 adolescents (aged 10-19) attending public secondary schools was done. Data were collected using facilitated self-administered questionnaires alongside a review of class records. Appropriate statistical analysis including multiple regression was done. Results showed mean age of respondents to be 14.6±2.1 years with prevalence of street hawking at 37.2%. Early adolescents (10-13 years) were more likely to engage in street hawking compared to their counterparts in late adolescence (aged 17-19). Female adolescents and students of trading mothers were significantly more likely to engage in street hawking. Respondents engaged in street hawking were significantly more likely to have failed the last academic term examination. The findings from this study will be useful for stakeholders as they develop policies and programmes to address the challenge of street hawking among adolescent school goers.

  19. Effects of Taping on Pain, Grip Strength and Wrist Extension Force in Patients with Tennis Elbow

    Directory of Open Access Journals (Sweden)

    Alireza Shamsoddini

    2013-09-01

    Full Text Available Background: Tennis elbow (TE is a common musculotendinous degenerative disorder of the extensor origin at the lateral humeral epicondyle. Different modes of treatment are used for management of tennis elbow.Objectives: This study investigated the effect of the taping technique (TT on pain, grip strength and wrist extension force in treatment of tennis elbow.Patients and Methods: Thirty patients (16 men /14 women with a mean age of 32.2 years with tennis elbow of their dominant arm participated in this study. Outcome measures were assessment of pain at the lateral aspect of the elbow, grip strength and wrist extension force before and five to ten minutes after application of elbow tape on the affected and unaffected arms. A Visual Analog Scale was used to assess pain. A dynamometer and a hand-held dynamometer were used for evaluation of grip strength and wrist extension force, respectively.Results: Among the variables, significant differences were found in wrist extension forces between effected and unaffected arms (P = 0.02. Changes in grip strength showed statically significant improvements in the affected arm compared to the unaffected arm (P = 0.03. Also, in assessment of pain at the lateral epicondyle, the mean change between affected and unaffected arms was significant, with P = 0.001.Conclusions: The taping technique, as applied in this study demonstrates an impressive effect on wrist extension force and grip strength of patients with TE. Elbow taping also reduces pain at the lateral aspect of the elbow in these patients.

  20. Enhanced independence: experiences after regaining grip function in people with tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Carlsson, Gunnel; Fridén, Jan

    2013-01-01

    To explore how surgical reconstruction of grip affects everyday life for patients with tetraplegia, with special emphasis on patients perspective of their perceived changes. Qualitative method. Eleven people (aged 22-73) with tetraplegia who had undergone surgical reconstruction to restore grip function. Qualitative interviews were conducted 7-17 months after surgery and analysed using Grounded theory. The core concept describing the participants experienced gains after grip reconstructive surgery was "enhanced independence". It was associated with changes in both practical and psychological aspects of independence. Practical aspects identified were: "perform more activities", "smoother everyday life", "renewed ability to participate in social activities", "less dependence on assistance" and "less restricted by physical environment". Psychological aspects of independence included "regained privacy", "increased manageability", "regained identity", "recapture a part of the body" and "share positive experiences with relatives and friends". Encompassing all categories was the concept "self-efficacy in hand control". It was seen as a result included in the enhanced independency core but also as an important factor for the development of all the other categories. Participants in this study experienced enhanced independence after grip reconstructive surgery and rehabilitation. The enhanced independence included both practical and physical aspects and it influenced all domains using the International Classification of Function, Disability and Health model; body function and structure, activities, participation, personal factors and environmental factors. Implications for Rehabilitation Patients with tetraplegia experience grip reconstruction as a useful intervention, an enhanced independence, related to their improved hand control. The increased hand control impacted not only physical aspects but also practical and psychological aspects. It also influenced social and