WorldWideScience

Sample records for avian field guide

  1. Avian survey and field guide for Osan Air Base, Korea.

    Energy Technology Data Exchange (ETDEWEB)

    Levenson, J.

    2006-12-05

    This report summarizes the results of the avian surveys conducted at Osan Air Base (AB). This ongoing survey is conducted to comply with requirements of the Environmental Governing Standards (EGS) for the Republic of Korea, the Integrated Natural Resources Management Plan (INRMP) for Osan AB, and the 51st Fighter Wing's Bird Aircraft Strike Hazard (BASH) Plan. One hundred ten bird species representing 35 families were identified and recorded. Seven species are designated as Natural Monuments, and their protection is accorded by the Korean Ministry of Culture and Tourism. Three species appear on the Korean Association for Conservation of Nature's (KACN's) list of Reserved Wild Species and are protected by the Korean Ministry of Environment. Combined, ten different species are Republic of Korea (ROK)-protected. The primary objective of the avian survey at Osan AB was to determine what species of birds are present on the airfield and their respective habitat requirements during the critical seasons of the year. This requirement is specified in Annex J.14.c of the 51st Fighter BASH Plan 91-212 (51 FW OPLAN 91-212). The second objective was to initiate surveys to determine what bird species are present on Osan AB throughout the year and from the survey results, determine if threatened, endangered, or other Korean-listed bird species are present on Osan AB. This overall census satisfies Criterion 13-3.e of the EGS for Korea. The final objective was to formulate management strategies within Osan AB's operational requirements to protect and enhance habitats of known threatened, endangered, and ROK-protected species in accordance with EGS Criterion 13-3.a that are also favorable for the reproduction of indigenous species in accordance with the EGS Criterion 13-3.h.

  2. Avian Field guide and checklist for Kunsan Air Base, Korea.

    Energy Technology Data Exchange (ETDEWEB)

    Levenson, J. B.; Environmental Assessment

    2005-11-15

    This report summarizes the results of the avian surveys conducted at Kunsan Air Base (AB). This on-going survey is conducted to comply with requirements of the Environmental Governing Standards (EGS) for the Republic of Korea, the Integrated Natural Resources Management Plan (INRMP) for Kunsan AB, and the 8th Fighter Wing's Bird Aircraft Strike Hazard (BASH) Plan. One hundred sixteen bird species representing 34 families were identified and recorded. Seven species are designated as Cultural Property Monuments, and their protection is accorded by the Korean Ministry of Culture and Tourism. Six species appear on the Korean Association for Conservation of Nature's(KACN's) list of Reserved Wild Species and are protected by the Korean Ministry of Environment. Combined, only ten different species are Republic of Korea (ROK)-protected because the Eurasian Spoonbill, Peregrine Falcon, and Eurasian Oystercatcher are listed by both agencies. The primary objective of the avian survey at Kunsan AB was to determine what species of birds are present on the airfield and their respective habitat requirements during the critical seasons of the year. This requirement is specified in Annex C.4.a.(1-4) of the 8th Fighter Wing BASH Plan(8FWOPLAN 91-202). The second objective was to initiate surveys to determine what bird species are present on Kunsan AB throughout the year, and from the survey results determine if threatened, endangered, or other Korean-listed bird species are present on Kunsan AB. This overall census satisfies Criterion 13-3.e of the EGS for Korea. The final objective was to formulate management strategies within Kunsan AB's operational requirements to protect and enhance habitats of known threatened, endangered, and ROK-protected species in accordance with EGS Criterion 13-3.a and also that are favorable for the reproduction of indigenous species in accordance with the EGS Criterion 13-3.h.

  3. Field guide to illumination

    CERN Document Server

    Arecchi, Angelo V; Koshel, R John

    2007-01-01

    The content in this Field Guide starts with traditional illumination in imaging systems, followed by the recent advances in computer-aided design of high-efficiency nonimaging illumination optics, along with the modern source models that support these techniques. Sections on the illumination of visual displays are included as well as some important topics on architectural illumination.

  4. Next-Generation Field Guides

    OpenAIRE

    Ellison, Aaron M.; Farnsworth, Elizabeth Jean; Chu, Miyoko; Kress, W. John; Neill, Amanda K.; Best, Jason H.; Pickering, John; Stevenson, Robert D.; Courtney, Gregory W.; VanDyk, John K.

    2013-01-01

    To conserve species, we must first identify them. Field researchers, land managers, educators, and citizen scientists need up-to-date and accessible tools to identify organisms, organize data, and share observations. Emerging technologies complement traditional, book-form field guides by providing users with a wealth of multimedia data. We review technical innovations of next-generation field guides, including Web-based and stand-alone applications, interactive multiple-access keys, visual-re...

  5. Field guide to nonlinear optics

    CERN Document Server

    Powers, Peter E

    2013-01-01

    Optomechanics is a field of mechanics that addresses the specific design challenges associated with optical systems. This [i]Field Guide [/i]describes how to mount optical components, as well as how to analyze a given design. It is intended for practicing optical and mechanical engineers whose work requires knowledge in both optics and mechanics. This Field Guide is designed for those looking for a condensed and concise source of key concepts, equations, and techniques for nonlinear optics. Topics covered include technologically important effects, recent developments in nonlinear optics

  6. New librarianship field guide

    CERN Document Server

    Lankes, R David

    2016-01-01

    This book offers a guide for librarians who see their profession as a chance to make a positive difference in their communities -- librarians who recognize that it is no longer enough to stand behind a desk waiting to serve. R. David Lankes, author of "The Atlas of New Librarianship," reminds librarians of their mission: to improve society by facilitating knowledge creation in their communities. In this book, he provides tools, arguments, resources, and ideas for fulfilling this mission. Librarians will be prepared to become radical positive change agents in their communities, and other readers will learn to understand libraries in a new way. The librarians of Ferguson, Missouri, famously became positive change agents in August 2014 when they opened library doors when schools were closed because of civil unrest after the shooting of an unarmed teen by police. Working with other local organizations, they provided children and their parents a space for learning, lunch, and peace. But other libraries serve othe...

  7. Field guide to adaptive optics

    CERN Document Server

    Tyson, Robert K

    2004-01-01

    ""...These field guides will be immensely useful to all scientists and engineers who wish to brush up on authentic definitions, equations, and tables of data in optics. And the format is really user friendly! I...wonder now how I ever got along in optics without this ready reference....a real winner!"" --Dr. Leno S. Pedrotti, Center for Occupational Research and Development (CORD) Third in the Field Guide Series, this is a summary of the methods for determining the requirements of an adaptive optics system, the performance of the system, and the requirements for the components of th

  8. Map of the Anlage fields in the avian unincubated blastoderm.

    Science.gov (United States)

    Callebaut, M; van Nueten, E; Bortier, H; Harrisson, F; van Nassauw, L

    1996-12-01

    By excision at different sites of rectangular fragments from unincubated chicken blastoderms and replacement by isotopic fragments from unincubated quail blastoderms, we could make the first complete map of the Anlage fields in the freshly laid avian blastoderm. All the Anlage fields (Fig. 11) are found in the upper layer (UL) of the caudal half of the area centralis (bordered by the Rauber-Koller's sickle). In the UL of the area marginalis, peripheral to Rauber-Koller's sickle, neither gastrulation nor neurulation phenomena could be observed. Similar heterotopic replacement experiments indicate that before incubation, the different parts of the UL of the area centralis are still uncommitted or reversibly committed. The Anlage fields of chordamesoblast and definitive endoderm (gut endoderm) in unincubated avian blastoderms appeared to be disposed caudally in the caudal half of the area centralis. As far as we know we are the first to demonstrate that the Anlage field of the definitive gut endoderm (which is derived from the upper layer: Hunt, 1937; Vakaet, 1962b) is localized in the most caudal upper layer part of the area centralis just centrally to the Rauber-Koller's sickle. The Anlage field of the neural plate is localized in the upper layer over the more cranial endophyll. The Anlage of the brain is shield-shaped, whilst the other Anlage fields are sickle-shaped, parallel with the Rauber-Koller's sickle. Their general hemicircular disposition and form still seem to reflect (together with the Rauber-Koller's sickle) the original ooplasmic radial symmetry (Callebaut, 1972) combined with the eccentricity of the deep layer components, which was observed during early symmetrization by gravitational orientation of the egg yolk (Callebaut, 1993a,b). The Rauber-Koller's sickle might be homologous with the vegetal dorsalizing cells or centre of Nieuwkoop (1973) in amphibian blastulas.

  9. Field guide to geometrical optics

    CERN Document Server

    Greivenkamp, John E

    2004-01-01

    This Field Guide derives from the treatment of geometrical optics that has evolved from both the undergraduate and graduate programs at the Optical Sciences Center at the University of Arizona. The development is both rigorous and complete, and it features a consistent notation and sign convention. This volume covers Gaussian imagery, paraxial optics, first-order optical system design, system examples, illumination, chromatic effects, and an introduction to aberrations. The appendices provide supplemental material on radiometry and photometry, the human eye, and several other topics.

  10. Pest Management Guide: Field Crops, 2014

    OpenAIRE

    Herbert, D. Ames (David Ames), 1949-

    2014-01-01

    This 2014 Virginia Pest Management Guide provides the latest recommendations for regulations and basic information, livestock, disease and nematode management in field crops, insects, weeds control, and plant regulators.

  11. A field guide to digital color

    CERN Document Server

    Stone, Maureen

    2013-01-01

    Maureen Stone's field guide to digital color presents a survey of digital color with special emphasis on those fields important for computer graphics. The book provides the foundation for understanding color and its applications, discusses color media and color management and the use of color in computer graphics, including color design and selection. The book provides a guide for anyone who wants to understand and apply digital color. An annotated bibliography provides in-depth references for further study on each topic.

  12. Pulsed field gel electrophoresis a practical guide

    CERN Document Server

    Birren, Bruce

    1993-01-01

    Pulsed Field Gel Electrophoresis: A Practical Guide is the first laboratory manual to describe the theory and practice of this technique. Based on the authors' experience developing pulsed field gel instruments and teaching procedures, this book provides everything a researcher or student needs to know in order to understand and carry out pulsed field gel experiments. Clear, well-tested protocols assume only that users have a basic familiarity with molecular biology. Thorough coverage of useful data, theory, and applications ensures that this book is also a lasting resource for more adv

  13. Empirical trials of plant field guides.

    Science.gov (United States)

    Hawthorne, W D; Cable, S; Marshall, C A M

    2014-06-01

    We designed 3 image-based field guides to tropical forest plant species in Ghana, Grenada, and Cameroon and tested them with 1095 local residents and 20 botanists in the United Kingdom. We compared users' identification accuracy with different image formats, including drawings, specimen photos, living plant photos, and paintings. We compared users' accuracy with the guides to their accuracy with only their prior knowledge of the flora. We asked respondents to score each format for usability, beauty, and how much they would pay for it. Prior knowledge of plant names was generally low (photos. Botanists in the United Kingdom accurately identified 82-93% of the same Cameroonian species; identification was most accurate with specimens. In Grenada, users accurately identified 74-82% of plants; drawings yielded significantly less accurate identifications than paintings and photos of living plants. In Ghana, users accurately identified 85% of plants. Digital color photos of living plants ranked high for beauty, usability, and what users would pay. Black and white drawings ranked low. Our results show the potential and limitations of the use of field guides and nonspecialists to identify plants, for example, in conservation applications. We recommend authors of plant field guides use the cheapest or easiest illustration format because image type had limited bearing on accuracy; match the type of illustration to the most likely use of the guide for slight improvements in accuracy; avoid black and white formats unless the audience is experienced at interpreting illustrations or keeping costs low is imperative; discourage false-positive identifications, which were common; and encourage users to ask an expert or use a herbarium for groups that are difficult to identify.

  14. SharePoint 2010 Field Guide

    CERN Document Server

    Mann, Steven; Gazmuri, Pablo; Caravajal, Steve; Wheeler, Christina

    2012-01-01

    Hands-on solutions for common SharePoint 2010 challenges Aimed at the more than 100 million licensed SharePoint 2010 users, this indispensable field guide addresses an abundance of common SharePoint 2010 problems and offers proven solutions. A team of authors encourages you to customize SharePoint beyond the out-of-the-box functionality so that you can build more complex solutions to these challenges. You?ll discover intricate details and specific full-scale solutions that you can then implement to your own SharePoint 2010 solutions.Tackles a variety of SharePoint 2010 problems ranging from si

  15. Intrinsic Properties Guide Proximal Abducens and Oculomotor Nerve Outgrowth in Avian Embryos

    OpenAIRE

    Lance-Jones, Cynthia; Shah, Veeral; Noden, Drew M; Sours, Emily

    2012-01-01

    Proper movement of the vertebrate eye requires the formation of precisely patterned axonal connections linking cranial somatic motoneurons, located at defined positions in the ventral midbrain and hindbrain, with extraocular muscles. The aim of this research was to assess the relative contributions of intrinsic, population-specific properties and extrinsic, outgrowth site-specific cues during the early stages of abducens and oculomotor nerve development in avian embryos. This was accomplished...

  16. Field Guides Made Easy. 4-H Leader's Guide L-5-21.

    Science.gov (United States)

    Phillips, Diane Held; Krasny, Marianne E.

    This illustrated leader's guide describes activities for teaching children to use field guides to identify trees and birds. Background information for leaders explains the two types of field guides, those that use a series of steps in what is called a key to identify things in nature, such as trees, and those that use groupings based on…

  17. Malware Forensics Field Guide for Windows Systems Digital Forensics Field Guides

    CERN Document Server

    Malin, Cameron H; Aquilina, James M

    2010-01-01

    Dissecting the dark side of the Internet with its infectious worms, botnets, rootkits, and Trojan horse programs (known as malware) is a treaterous condition for any forensic investigator or analyst. Written by information security experts with real-world investigative experience, Malware Forensics Field Guide for Windows Systems is a "tool" with checklists for specific tasks, case studies of difficult situations, and expert analyst tips. *A condensed hand-held guide complete with on-the-job tasks and checklists *Specific for Windows-based systems, the largest running OS in the world

  18. Relativistic Two-fluid Simulations of Guide Field Magnetic Reconnection

    CERN Document Server

    Zenitani, Seiji; Klimas, Alex

    2009-01-01

    The nonlinear evolution of relativistic magnetic reconnection in sheared magnetic configuration (with a guide field) is investigated by using two-dimensional relativistic two-fluid simulations. Relativistic guide field reconnection features the charge separation and the guide field compression in and around the outflow channel. As the guide field increases, the composition of the outgoing energy changes from enthalpy-dominated to Poynting-dominated. The inertial effects of the two-fluid model play an important role to sustain magnetic reconnection. Implications for the single fluid magnetohydrodynamic approach and the physics models of relativistic reconnection are briefly addressed.

  19. Field Hockey; Lacrosse, June 1976-June 1978. NAGWS Guide.

    Science.gov (United States)

    Nixon, Linda K., Ed.; Hess, Eleanor Kay, Ed.

    This guide for field hockey and lacrosse is one in a series of guides for 22 sports published by the National Association for Girls and Women in Sport (NAGWS). Guides contain information on NAGWS-approved playing rules, officials' ratings, articles on teaching, coaching and organization, regulations governing national championships,…

  20. Recovery Based Nanowire Field-Effect Transistor Detection of Pathogenic Avian Influenza DNA

    Science.gov (United States)

    Lin, Chih-Heng; Chu, Chia-Jung; Teng, Kang-Ning; Su, Yi-Jr; Chen, Chii-Dong; Tsai, Li-Chu; Yang, Yuh-Shyong

    2012-02-01

    Fast and accurate diagnosis is critical in infectious disease surveillance and management. We proposed a DNA recovery system that can easily be adapted to DNA chip or DNA biosensor for fast identification and confirmation of target DNA. This method was based on the re-hybridization of DNA target with a recovery DNA to free the DNA probe. Functionalized silicon nanowire field-effect transistor (SiNW FET) was demonstrated to monitor such specific DNA-DNA interaction using high pathogenic strain virus hemagglutinin 1 (H1) DNA of avian influenza (AI) as target. Specific electric changes were observed in real-time for AI virus DNA sensing and device recovery when nanowire surface of SiNW FET was modified with complementary captured DNA probe. The recovery based SiNW FET biosensor can be further developed for fast identification and further confirmation of a variety of influenza virus strains and other infectious diseases.

  1. Coordinated Eph-ephrin signaling guides migration and axon targeting in the avian auditory system

    Directory of Open Access Journals (Sweden)

    Allen-Sharpley Michelle R

    2012-08-01

    Full Text Available Abstract Background In the avian sound localization circuit, nucleus magnocellularis (NM projects bilaterally to nucleus laminaris (NL, with ipsilateral and contralateral NM axon branches directed to dorsal and ventral NL dendrites, respectively. We previously showed that the Eph receptor EphB2 is expressed in NL neuropil and NM axons during development. Here we tested whether EphB2 contributes to NM-NL circuit formation. Results We found that misexpression of EphB2 in embryonic NM precursors significantly increased the number of axon targeting errors from NM to contralateral NL in a cell-autonomous manner when forward signaling was impaired. We also tested the effects of inhibiting forward signaling of different Eph receptor subclasses by injecting soluble unclustered Fc-fusion proteins at stages when NM axons are approaching their NL target. Again we found an increase in axon targeting errors compared to controls when forward signaling was impaired, an effect that was significantly increased when both Eph receptor subclasses were inhibited together. In addition to axon targeting errors, we also observed morphological abnormalities of the auditory nuclei when EphB2 forward signaling was increased by E2 transfection, and when Eph-ephrin forward signaling was inhibited by E6-E8 injection of Eph receptor fusion proteins. Conclusions These data suggest that EphB signaling has distinct functions in axon guidance and morphogenesis. The results provide evidence that multiple Eph receptors work synergistically in the formation of precise auditory circuitry.

  2. Investigating poultry trade patterns to guide avian influenza surveillance and control: a case study in Vietnam.

    Science.gov (United States)

    Fournié, Guillaume; Tripodi, Astrid; Nguyen, Thi Thanh Thuy; Nguyen, Van Trong; Tran, Trong Tung; Bisson, Andrew; Pfeiffer, Dirk U; Newman, Scott H

    2016-01-01

    Live bird markets are often the focus of surveillance activities monitoring avian influenza viruses (AIV) circulating in poultry. However, in order to ensure a high sensitivity of virus detection and effectiveness of management actions, poultry management practices features influencing AIV dynamics need to be accounted for in the design of surveillance programmes. In order to address this knowledge gap, a cross-sectional survey was conducted through interviews with 791 traders in 18 Vietnamese live bird markets. Markets greatly differed according to the sources from which poultry was obtained, and their connections to other markets through the movements of their traders. These features, which could be informed based on indicators that are easy to measure, suggest that markets could be used as sentinels for monitoring virus strains circulating in specific segments of the poultry production sector. AIV spread within markets was modelled. Due to the high turn-over of poultry, viral amplification was likely to be minimal in most of the largest markets. However, due to the large number of birds being introduced each day, and challenges related to cleaning and disinfection, environmental accumulation of viruses at markets may take place, posing a threat to the poultry production sector and to public health. PMID:27405887

  3. Investigating poultry trade patterns to guide avian influenza surveillance and control: a case study in Vietnam

    Science.gov (United States)

    Fournié, Guillaume; Tripodi, Astrid; Nguyen, Thi Thanh Thuy; Nguyen, Van Trong; Tran, Trong Tung; Bisson, Andrew; Pfeiffer, Dirk U.; Newman, Scott H.

    2016-01-01

    Live bird markets are often the focus of surveillance activities monitoring avian influenza viruses (AIV) circulating in poultry. However, in order to ensure a high sensitivity of virus detection and effectiveness of management actions, poultry management practices features influencing AIV dynamics need to be accounted for in the design of surveillance programmes. In order to address this knowledge gap, a cross-sectional survey was conducted through interviews with 791 traders in 18 Vietnamese live bird markets. Markets greatly differed according to the sources from which poultry was obtained, and their connections to other markets through the movements of their traders. These features, which could be informed based on indicators that are easy to measure, suggest that markets could be used as sentinels for monitoring virus strains circulating in specific segments of the poultry production sector. AIV spread within markets was modelled. Due to the high turn-over of poultry, viral amplification was likely to be minimal in most of the largest markets. However, due to the large number of birds being introduced each day, and challenges related to cleaning and disinfection, environmental accumulation of viruses at markets may take place, posing a threat to the poultry production sector and to public health. PMID:27405887

  4. Field Investigation on the Prevalence of Avian Influenza Virus Infection in Some Localities in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abdullah N. Alkhalaf

    2010-07-01

    Full Text Available The objective of this study was to find out prevalence and types of avian influenza virus (AIV among broilers, native chickens, ducks and pigeons in Saudi Arabia. Field investigation was carried out in four localities including Al-Qassim, Hail, Al-Jouf and Northern Border regions. Serum sample, tracheal and cloacal swabs were collected from broilers (n=1561, layers (n=988, ducks (n=329 and pigeons (n=450 from these localities and tested for three different avian influenza viruses (H9, H5 and H3 using Enzyme linked immunosorbent (ELISA test, hamagglutination inhibition (HI test and polymerase chain reaction (PCR. All tested samples were negative for H5 and H3 viruses. In contrast, all positive results were found to be for H9 AI virus using PCR, ELISA and HI test. Chicken sera tested by ELISA for AIV revealed the highest positive samples in Northern Border regions (45.71%, followed by Al-Jouf (29.65%, Al-Qassim (23.98% and Hial (20.94% with non-significant difference (χ2=5.983; P=0.112. HI test carried out on duck sera revealed 35.90% prevalence of antibodies against AIV. PCR amplification resulted in 34.28 and 21.36% positive samples in ducks and chickens, respectively. The highest (45.71% PCR positive chicken samples were from Northern Border regions, followed by Al-Jouf (24.13%, Al-Qassim (19.30% and Hail (16.69% with significant difference (χ2=7.620; P=0.055. All tested pigeons samples were negative for the three virus serotypes included in the study.

  5. Intrinsic properties guide proximal abducens and oculomotor nerve outgrowth in avian embryos.

    Science.gov (United States)

    Lance-Jones, Cynthia; Shah, Veeral; Noden, Drew M; Sours, Emily

    2012-02-01

    Proper movement of the vertebrate eye requires the formation of precisely patterned axonal connections linking cranial somatic motoneurons, located at defined positions in the ventral midbrain and hindbrain, with extraocular muscles. The aim of this research was to assess the relative contributions of intrinsic, population-specific properties and extrinsic, outgrowth site-specific cues during the early stages of abducens and oculomotor nerve development in avian embryos. This was accomplished by surgically transposing midbrain and caudal hindbrain segments, which had been pre-labeled by electroporation with an EGFP construct. Graft-derived EGFP+ oculomotor axons entering a hindbrain microenvironment often mimicked an abducens initial pathway and coursed cranially. Similarly, some EGFP+ abducens axons entering a midbrain microenvironment mimicked an oculomotor initial pathway and coursed ventrally. Many but not all of these axons subsequently projected to extraocular muscles that they would not normally innervate. Strikingly, EGFP+ axons also took initial paths atypical for their new location. Upon exiting from a hindbrain position, most EGFP+ oculomotor axons actually coursed ventrally and joined host branchiomotor nerves, whose neurons share molecular features with oculomotor neurons. Similarly, upon exiting from a midbrain position, some EGFP+ abducens axons turned caudally, elongated parallel to the brainstem, and contacted the lateral rectus muscle, their originally correct target. These data reveal an interplay between intrinsic properties that are unique to oculomotor and abducens populations and shared ability to recognize and respond to extrinsic directional cues. The former play a prominent role in initial pathway choices, whereas the latter appear more instructive during subsequent directional choices. PMID:21739615

  6. Magnetic Field Analysis of Plasma Guide in Galathea Trimyx

    Directory of Open Access Journals (Sweden)

    Jin Xianji

    2016-01-01

    Full Text Available You Galathea Trimyx is a kind of small size, multipole magnetic confinement devices in controlled thermonuclear fusion. Plasma guide is one of important part in Galathea Trimyx which is responsible for transporting fast and slow plasma bunches ejected from plasma gun. The distribution and uniformity of magnetic field in completed plasma guide is analyzed in detail, including in x -axis direction and in z-axis direction. On the basis, the motion of plasma in the guide is discussed.

  7. Magnetic Field Analysis of Plasma Guide in Galathea Trimyx

    OpenAIRE

    Jin Xianji; Tong Weiming; Zhou Tianyi

    2016-01-01

    You Galathea Trimyx is a kind of small size, multipole magnetic confinement devices in controlled thermonuclear fusion. Plasma guide is one of important part in Galathea Trimyx which is responsible for transporting fast and slow plasma bunches ejected from plasma gun. The distribution and uniformity of magnetic field in completed plasma guide is analyzed in detail, including in x -axis direction and in z-axis direction. On the basis, the motion of plasma in the guide is discussed.

  8. A Guided Inquiry Activity for Teaching Ligand Field Theory

    Science.gov (United States)

    Johnson, Brian J.; Graham, Kate J.

    2015-01-01

    This paper will describe a guided inquiry activity for teaching ligand field theory. Previous research suggests the guided inquiry approach is highly effective for student learning. This activity familiarizes students with the key concepts of molecular orbital theory applied to coordination complexes. Students will learn to identify factors that…

  9. Effect of Guiding Magnetic Field on Weibel Instability

    Institute of Scientific and Technical Information of China (English)

    LI Ji-Wei; PEI Wen-Bing

    2005-01-01

    @@ We derive a linear dispersion relation in the presence of a constant uniform guiding magnetic field parallel to the beam velocity direction, which shows a strong background magnetic field suppresses or even stabilizes the Weibel instability produced by two counter streams in electron-ion plasmas. The simulation results are in good agreement with the analytical ones. Also observed in the simulations are the suppression of electrostatic field, a higher level of saturation of self-generated magnetic field, and the apparent difference in phase space compared with those in the absence of guiding magnetic field.

  10. Field guide to fishes of the chesapeake bay

    CERN Document Server

    Murdy, Edward O.

    2013-01-01

    The only comprehensive field guide to the Chesapeake’s fishes, this book is an indispensable resource for both anglers and students of the Bay. Vivid illustrations by Val Kells complement the expertise of researchers Edward O. Murdy and John A. Musick. They describe fishes that inhabit waters ranging from low-salinity estuaries to the point where the Bay meets the Atlantic Ocean. Key features of this field guide include• full-color illustrations of more than 200 species• text that is presented adjacent to illustrations for easy reference• detailed descriptions of physical characteristics, range, occurrence in the Bay, reproduction, diet, and statistics from fisheries research• spot illustrations that highlight critical features of certain fish• illustrations of juveniles when they look different from adults• appendices that include identification keys Formatted as a compact field guide for students, scientists, researchers, and fishermen, Field Guide to Fishes of the Chesapeake Bay should be a ...

  11. Field Hockey-Lacrosse Guide. June 1974-June 1976.

    Science.gov (United States)

    Ramser, Frances, Ed.; Bixler, Agnes, Ed.

    This guide is a collection of essays by various authors on field hockey and lacrosse. There is a separate section for each sport. The topics covered in the field hockey section include half-time coaching, visual aids, umpiring techniques and ratings, goalkeeper training, experimental field hockey rules, and the code of rules for the game of hockey…

  12. Observing the sun a pocket field guide

    CERN Document Server

    Jenkins, Jamey L

    2013-01-01

    A comprehensive solar observing guide for use at the telescope by amateur astronomers at all three levels: beginning, intermediate, and advanced. Users will find invaluable information for identifying features through photos, charts, diagrams in a logical, orderly fashion and then interpreting the observations. Because the Sun is a dynamic celestial body in constant flux, astronomers rarely know for certain what awaits them at the eyepiece. All features of the Sun are transient and sometimes rather fleeting. Given the number of features and the complex life cycles of some solar features, it can be a challenging hobby, and this guide provides all of the guidance necessary to inform observers about the sights and events unfolding before their eyes on the most active and powerful member of our Solar System.

  13. Field Guide to Meteors and Meteorites

    CERN Document Server

    Norton, O. Richard

    2008-01-01

    Imagine the unique experience of being the very first person to hold a newly-found meteorite in your hand – a rock from space, older than Earth! "Weekend meteorite hunting" with magnets and metal detectors is becoming ever more popular as a pastime, but of course you can’t just walk around and pick up meteorites in the same way that you can pick up seashells on the beach. Those fragments that survived the intense heat of re-entry tend to disguise themselves as natural rocks over time, and it takes a trained eye – along with the information in this book – to recognize them. Just as amateur astronomers are familiar with the telescopes and accessories needed to study a celestial object, amateur meteoriticists have to use equipment ranging from simple hand lenses to microscopes to study a specimen, to identify its type and origins. Equipment and techniques are covered in detail here of course, along with a complete and fully illustrated guide to what you might find and where you might find it. In fact, th...

  14. Avian Plasmodium infection in field-collected mosquitoes during 2012-2013 in Tarlac, Philippines.

    Science.gov (United States)

    Chen, Tien-Huang; Aure, Wilfredo E; Cruz, Estrella Irlandez; Malbas, Fedelino F; Teng, Hwa-Jen; Lu, Liang-Chen; Kim, Kyeong Soon; Tsuda, Yoshio; Shu, Pei-Yun

    2015-12-01

    Global warming threatens to increase the spread and prevalence of mosquito-transmitted diseases. Certain pathogens may be carried by migratory birds and transmitted to local mosquito populations. Mosquitoes were collected in the northern Philippines during bird migration seasons to detect avian malaria parasites as well as for the identification of potential vector species and the estimation of infections among local mosquito populations. We used the nested PCR to detect the avian malaria species. Culex vishnui (47.6%) was the most abundant species collected and Cx. tritaeniorhynchus (13.8%) was the second most abundant. Avian Plasmodium parasites were found in eight mosquito species, for which the infection rates were between 0.5% and 6.2%. The six Plasmodium genetic lineages found in this study included P. juxtanucleare -GALLUS02, Tacy7 (Donana04), CXBIT01, Plasmodium species LIN2 New Zealand, and two unclassified lineages. The potential mosquito vectors for avian Plasmodium parasites in the Philippines were Cq. crassipes, Cx. fuscocephala, Cx. quinquefasciatus, Cx. sitiens, Cx. vishnui, and Ma. Uniformis; two major genetic lineages, P. juxtanucleare and Tacy7, were identified.

  15. The Norwegian Sphagna: a field colour guide

    OpenAIRE

    Flatberg, Kjell I.

    2002-01-01

    Colour plates illustrate fifty-four Sphagnum taxa, 50 species and 4 subspecies. This constitues all the known peat mosses from Norway including arctic Svalbard. Macroscopic keys to sections and species within the different sections are presented. These keys used in combination with the colour plates and a hand lens should in most cases enable the correct determination of the Norwegian peat mosses in the field.

  16. The wireshark field guide analyzing and troubleshooting network traffic

    CERN Document Server

    Shimonski, Robert

    2013-01-01

    The Wireshark Field Guide provides hackers, pen testers, and network administrators with practical guidance on capturing and interactively browsing computer network traffic. Wireshark is the world's foremost network protocol analyzer, with a rich feature set that includes deep inspection of hundreds of protocols, live capture, offline analysis and many other features. The Wireshark Field Guide covers the installation, configuration and use of this powerful multi-platform tool. The book give readers the hands-on skills to be more productive with Wireshark as they drill

  17. On guided versus deflected fields in controlled-source electromagnetics

    Science.gov (United States)

    Swidinsky, Andrei

    2015-06-01

    The detection of electrically resistive targets in applied geophysics is of interest to the hydrocarbon, mining and geotechnical industries. Elongated thin resistive bodies have been extensively studied in the context of offshore hydrocarbon exploration. Such targets guide electromagnetic fields in a process which superficially resembles seismic refraction. On the other hand, compact resistive bodies deflect current in a process which has more similarities to diffraction and scattering. The response of a real geological structure is a non-trivial combination of these elements-guiding along the target and deflection around its edges. In this note the electromagnetic responses of two end-member models are compared: a resistive layer, which guides the electromagnetic signal, and a resistive cylinder, which deflects the fields. Results show that the response of a finite resistive target tends to saturate at a much lower resistivity than a resistive layer, under identical survey configurations. Furthermore, while the guided electromagnetic fields generated by a buried resistive layer contain both anomalous horizontal and vertical components, the process of electromagnetic deflection from a buried resistive cylinder creates mainly anomalous vertical fields. Finally, the transmitter orientation with respect to the position of a finite body is an important survey parameter: when the distance to the target is much less than the host skin depth, a transmitter pointing towards the resistive cylinder will produce a stronger signal than a transmitter oriented azimuthally with respect to the cylinder surface. The opposite situation is observed when the distance to the target is greater than the host skin depth.

  18. A field guide for well site geologists: Cable tool drilling

    International Nuclear Information System (INIS)

    This field is intended for use by Pacific Northwest Laboratory well site geologists who are responsible for data collection during the drilling and construction of monitoring wells on the Hanford Site. This guide presents standardized methods for geologic sample collection and description, and well construction documentation. 5 refs., 5 figs., 2 tabs

  19. A field ornithologist’s guide to genomics: Practical considerations for ecology and conservation

    Science.gov (United States)

    Oyler-McCance, Sara J.; Oh, Kevin; Langin, Kathryn; Aldridge, Cameron L.

    2016-01-01

    Vast improvements in sequencing technology have made it practical to simultaneously sequence millions of nucleotides distributed across the genome, opening the door for genomic studies in virtually any species. Ornithological research stands to benefit in three substantial ways. First, genomic methods enhance our ability to parse and simultaneously analyze both neutral and non-neutral genomic regions, thus providing insight into adaptive evolution and divergence. Second, the sheer quantity of sequence data generated by current sequencing platforms allows increased precision and resolution in analyses. Third, high-throughput sequencing can benefit applications that focus on a small number of loci that are otherwise prohibitively expensive, time-consuming, and technically difficult using traditional sequencing methods. These advances have improved our ability to understand evolutionary processes like speciation and local adaptation, but they also offer many practical applications in the fields of population ecology, migration tracking, conservation planning, diet analyses, and disease ecology. This review provides a guide for field ornithologists interested in incorporating genomic approaches into their research program, with an emphasis on techniques related to ecology and conservation. We present a general overview of contemporary genomic approaches and methods, as well as important considerations when selecting a genomic technique. We also discuss research questions that are likely to benefit from utilizing high-throughput sequencing instruments, highlighting select examples from recent avian studies.

  20. Relativistic Hamiltonian Guiding Centre Drift Orbits in General Perturbed Fields

    International Nuclear Information System (INIS)

    Full text: A relativistic extension to the Hamiltonian/Lagrangian theory of guiding centre orbit drift motion is performed, including full electromagnetic perturbed fields in anisotropic pressure 3D equilibria with nested magnetic flux surfaces. First establishing a set of canonical Boozer coordinates, the guiding centre particle radial drift motion and parallel gyroradius evolution are then derived. The resulting equations of motion a particularly relevant to investigate hot particles in confined plasmas and address the problem of runaway electrons in devices such as ITER. (author)

  1. Three-Dimensional Modeling of Guide-Field Magnetic Reconnection

    Science.gov (United States)

    Hesse, Michael

    2005-01-01

    The dissipation mechanism of guide field magnetic reconnection remains a subject of intense scientific interest. On one hand, one set of recent studies have shown that particle inertia-based processes, which include thermal and bulk inertial effects, provide the reconnection electric field in the diffusion region. On the other hand, a second set of studies emphasizes the role of wave-particle interactions in providing anomalous resistivity in the diffusion region. In this presentation, we analyze three-dimensional PIC simulations of guide-field magnetic reconnection. Specific emphasis will be on the question whether thermal-inertia processes, mediated by the electron pressure tensor, remain a viable dissipation mechanism in fully three-dimensional systems.

  2. Avian influenza

    Science.gov (United States)

    Bird flu; H5N1; H5N2; H5N8; H7N9; Avian influenza A (HPAI) H5 ... The first avian influenza in humans was reported in Hong Kong in 1997. It was called avian influenza (H5N1). The outbreak was linked ...

  3. GUIDING OF PLASMA BY ELECTRIC FIELD AND MAGNETIC FIELD

    Institute of Scientific and Technical Information of China (English)

    ZHANG TAO; HOU JUN-DA; TANG BAO-YIN; P. K. CHU; I. G. BROWN

    2001-01-01

    The relationship between the transported ion current and the cathodic arc current is determined in a vacuum arc plasma source equipped with a curved magnetic filter. Our results suggest that the outer and inner walls of the duct interact with the plasma independently. The duct magnetic field is a critical factor of the plasma output. The duct transport efficiency is to maximize at a value of bias plate voltage in the range +10 V to +20 V, and independent (within our limit of measurement) of the magnetic field strength in the duct. The plasma flux is composed of two components:a diffusion flux in the transverse direction due to particle collisions, and a drift flux due to the ion inertia. The inner wall of the magnetic duct sees only the diffusion flux while the outer wall receives both fluxes. Thus, applying a positive potential to the outer duct wall can reflect the ions and increase the output current. Our experimental data also show that biasing both sides of the duct is more effective than biasing the outer wall alone.

  4. A Field Guide for Science Writers - The Official Guide of the National Association of Science Writers

    Science.gov (United States)

    Blum, Deborah; Knudson, Mary; Marantz Henig, Robin

    2005-09-01

    This is the official text for the National Association of Science Writers. In the eight years since the publication of the first edition of A Field Guide for Science Writing, much about the world has changed. Some of the leading issues in today's political marketplace - embryonic stem cell research, global warming, health care reform, space exploration, genetic privacy, germ warfare - are informed by scientific ideas. Never has it been more crucial for the lay public to be scientifically literate. That's where science writers come in. And that's why it's time for an update to the Field Guide, already a staple of science writing graduate programs across the country. The academic community has recently recognized how important it is for writers to become more sophisticated, knowledgeable, and skeptical about what they write. More than 50 institutions now offer training in science writing. In addition mid-career fellowships for science writers are growing, giving journalists the chance to return to major universities for specialized training. We applaud these developments, and hope to be part of them with this new edition of the Field Guide. In A Field Guide for Science Writers, 2nd Edition, the editors have assembled contributions from a collections of experienced journalists who are every bit as stellar as the group that contributed to the first edition. In the end, what we have are essays written by the very best in the science writing profession. These wonderful writers have written not only about style, but about content, too. These leaders in the profession describe how they work their way through the information glut to find the gems worth writing about. We also have chapters that provide the tools every good science writer needs: how to use statistics, how to weigh the merits of conflicting studies in scientific literature, how to report about risk. And, ultimately, how to write.

  5. Sweet reason a field guide to modern logic

    CERN Document Server

    Henle, James M; Tymoczko, Thomas; Altreuter, Emily

    2011-01-01

    Sweet Reason: A Field Guide to Modern Logic, 2nd Edition offers an innovative, friendly, and effective introduction to logic. It integrates formal first order, modal, and non-classical logic with natural language reasoning, analytical writing, critical thinking, set theory, and the philosophy of logic and mathematics.An innovative introduction to the field of logic designed to entertain as it informsIntegrates formal first order, modal, and non-classical logic with natural language reasoning, analytical writing, critical thinking, set theory, and the philosophy of

  6. Localized Electron Heating by Strong Guide-Field Magnetic Reconnection

    Science.gov (United States)

    Guo, Xuehan; Sugawara, Takumichi; Inomoto, Michiaki; Yamasaki, Kotaro; Ono, Yasushi; UTST Team

    2015-11-01

    Localized electron heating of magnetic reconnection was studied under strong guide-field (typically Bt 15Bp) using two merging spherical tokamak plasmas in Univ. Tokyo Spherical Tokamak (UTST) experiment. Our new slide-type two-dimensional Thomson scattering system documented for the first time the electron heating localized around the X-point. The region of high electron temperature, which is perpendicular to the magnetic field, was found to have a round shape with radius of 2 [cm]. Also, it was localized around the X-point and does not agree with that of energy dissipation term Et .jt . When we include a guide-field effect term Bt / (Bp + αBt) for Et .jt where α =√{ (vin2 +vout2) /v∥2 } , the energy dissipation area becomes localized around the X-point, suggesting that the electrons are accelerated by the reconnection electric field parallel to the magnetic field and thermalized around the X-point. This work was supported by JSPS A3 Foresight Program ``Innovative Tokamak Plasma Startup and Current Drive in Spherical Torus,'' a Grant-in-Aid from the Japan Society for the Promotion of Science (JSPS) Fellows 15J03758.

  7. Earth magnetism a guided tour through magnetic fields

    CERN Document Server

    Campbell, Wallace H

    2001-01-01

    An introductory guide to global magnetic field properties, Earth Magnetism addresses, in non-technical prose, many of the frequently asked questions about Earth''s magnetic field. Magnetism surrounds and penetrates our Earth in ways basic science courses can rarely address. It affects navigation, communication, and even the growth of crystals. As we observe and experience an 11-year solar maximum, we may witness spectacular satellite-destroying solar storms as they interact with our magnetic field. Written by an acknowledged expert in the field, this book will enrich courses in earth science, atmospheric science, geology, meteorology, geomagnetism, and geophysics. Contains nearly 200 original illustrations and eight pages of full-color plates.* Largely mathematics-free and with a wide breadth of material suitable for general readers* Integrates material from geomagnetism, paleomagnetism, and solar-terrestrial space physics.* Features nearly 200 original illustrations and 4 pages of colour plates

  8. MR image-guided portal verification for brain treatment field

    International Nuclear Information System (INIS)

    Purpose: To investigate a method for the generation of digitally reconstructed radiographs directly from MR images (DRR-MRI) to guide a computerized portal verification procedure. Methods and Materials: Several major steps were developed to perform an MR image-guided portal verification procedure. Initially, a wavelet-based multiresolution adaptive thresholding method was used to segment the skin slice-by-slice in MR brain axial images. Some selected anatomical structures, such as target volume and critical organs, were then manually identified and were reassigned to relatively higher intensities. Interslice information was interpolated with a directional method to achieve comparable display resolution in three dimensions. Next, a ray-tracing method was used to generate a DRR-MRI image at the planned treatment position, and the ray tracing was simply performed on summation of voxels along the ray. The skin and its relative positions were also projected to the DRR-MRI and were used to guide the search of similar features in the portal image. A Canny edge detector was used to enhance the brain contour in both portal and simulation images. The skin in the brain portal image was then extracted using a knowledge-based searching technique. Finally, a Chamfer matching technique was used to correlate features between DRR-MRI and portal image. Results: The MR image-guided portal verification method was evaluated using a brain phantom case and a clinical patient case. Both DRR-CT and DRR-MRI were generated using CT and MR phantom images with the same beam orientation and then compared. The matching result indicated that the maximum deviation of internal structures was less than 1 mm. The segmented results for brain MR slice images indicated that a wavelet-based image segmentation technique provided a reasonable estimation for the brain skin. For the clinical patient case with a given portal field, the MR image-guided verification method provided an excellent match between

  9. Efficient Injection of Electron Beams into Magnetic Guide Fields

    International Nuclear Information System (INIS)

    Preliminary experimental and modeling study of injection and transport of high current electron beams in current-neutralized background gas has been performed. Initial analysis of the results indicates that high current triaxial ring diode operates very reproducibly in the pinch mode. High current density beam can be injected efficiently into the drift region, using azimuthal guide field with reduced intensity near the injection region. This was shown to improve the effectiveness of capturing the beam for the transport. The transport length was insufficient to measure losses, such as would arise from scattering with the background gas

  10. Efficient Injection of Electron Beams into Magnetic Guide Fields

    Energy Technology Data Exchange (ETDEWEB)

    Chorny, V.; Cooperstein, G.; Dubyna, V.; Frolov, O.; Harper-Slaboszewicz, V.; Hinshelwood, D.; Schneider, R.; Solovyov, V.; Tsepilov, H.; Vitkovitsky, I.; Ware, K,

    1999-06-08

    Preliminary experimental and modeling study of injection and transport of high current electron beams in current-neutralized background gas has been performed. Initial analysis of the results indicates that high current triaxial ring diode operates very reproducibly in the pinch mode. High current density beam can be injected efficiently into the drift region, using azimuthal guide field with reduced intensity near the injection region. This was shown to improve the effectiveness of capturing the beam for the transport. The transport length was insufficient to measure losses, such as would arise from scattering with the background gas.

  11. Field Guide to Nonindigenous Marine Fishes of Florida

    OpenAIRE

    Schofield, Pamela J.; Morris, Jr., J. Glenn; Akins, Lad

    2009-01-01

    The purpose of this field guide is to provide information on nonindigenous (i.e., non-native) fishes that have been observed in Florida’s marine waters. Introductions of non-native marine fishes into Florida’s waters could be intentional or unintentional, and are likely from a variety of sources, including aquarium releases, escape from aquaculture, loss due to extreme weather events (e.g., flooding from hurricanes), and possibly transfer with ballast water or hull-fouling. Presently the lion...

  12. Turbulent transport in 2D collisionless guide field reconnection

    CERN Document Server

    Muñoz, P A; Kilian, P

    2016-01-01

    Transport in collisionless plasmas is usually called anomalous, being due to the interaction between the particles and the self-generated turbulence by their collective interactions. Because of its relevance for astrophysical and space plasmas, we explore the excitation of turbulence in current sheets prone to component- or guide-field reconnection, a process not well understood, yet. We analyze the anomalous transport properties by using 2.5D Particle-in-Cell (PiC) code simulations. We split off the mean, slow variation (in contrast to the fast turbulent fluctuations) of the macroscopic observables and determine the main transport terms of the generalized Ohm's law. We verify our findings by comparing with the independently determined slowing-down rate of the macroscopic currents and with the transport terms obtained by the first order correlations of the turbulent fluctuations. We find that the turbulence is most intense in the "low density" separatrix region of guide-field reconnection. It is excited by st...

  13. A Simple Field Guides to Identify Fire Effects on Soils

    Science.gov (United States)

    Robichaud, Peter

    2016-04-01

    Following wildfires post fire assessment personnel or teams assess immediate post-fire watershed conditions. These assessment teams must determine threats from flooding, soil erosion, and instability in a relatively short time period. Various tools and guides have been developed to assist in that process. A soil burn severity map is often the first step in the rapid assessment process. It enables BAER teams to prioritize field reviews and locate burned areas that may pose a risk to critical values within or downstream of the burned area. Five field parameters are easily determined in the field 1) remaining ground cover and characteristic, 2) ash color and depth, 3) soil structure, 4) fine roots, and 5) soil water repellency. All parameters are visual identified except water repellency which can be determined by the Water Drop Penetration Time (WDPT) test or Mini-Disk Infiltrometer (MDI). Often times the MDI test takes less time, is less subjective, and provides a relative infiltration rate which the WDPT test does not. The MDI test results are often put into "degree of soil water repellency" categories (strong, weak, and none). These field procedures that indicate the fire effects on the soil conditions help assessment teams consistently interpret, field validate and map soil burn severity.

  14. Specific detection of H5N1 avian influenza A virus in field specimens by a one-step RT-PCR assay

    Directory of Open Access Journals (Sweden)

    Gupta Sanjay

    2006-03-01

    Full Text Available Abstract Background Continuous outbreaks of the highly pathogenic H5N1 avian influenza A in Asia has resulted in an urgent effort to improve current diagnostics to aid containment of the virus and lower the threat of a influenza pandemic. We report here the development of a PCR-based assay that is highly specific for the H5N1 avian influenza A virus. Methods A one-step reverse-transcription PCR assay was developed to detect the H5N1 avian influenza A virus. The specificity of the assay was shown by testing sub-types of influenza A virus and other viral and bacterial pathogens; and on field samples. Results Validation on 145 field specimens from Vietnam and Malaysia showed that the assay was specific without cross reactivity to a number of other infuenza strains as well as human respiratory related pathogens. Detection was 100% from allantoic fluid in H5N1 positive samples, suggesting it to be a reliable sampling source for accurate detection. Conclusion The assay developed from this study indicates that the primers are specific for the H5N1 influenza virus. As shown by the field tested results, this assay would be highly useful as a diagnostic tool to help identify and control influenza epidemics.

  15. Avian influenza

    Science.gov (United States)

    ... avian influenza A in Asia, Africa, Europe, Indonesia, Vietnam, the Pacific, and the near East. Hundreds of ... to detect abnormal breath sounds) Chest x-ray Culture from the nose or throat A method or ...

  16. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,Avian Research provides a unique opportunity to publish high quality contents that will be internationally accessible to any reader at no cost.

  17. Avian Flu

    Energy Technology Data Exchange (ETDEWEB)

    Eckburg, Paul

    2006-11-06

    Since 2003, a severe form of H5N1 avian influenza has rapidly spread throughout Asia and Europe, infecting over 200 humans in 10 countries. The spread of H5N1 virus from person-to-person has been rare, thus preventing the emergence of a widespread pandemic. However, this ongoing epidemic continues to pose an important public health threat. Avian flu and its pandemic potential in humans will be discussed.

  18. Avian Flu

    International Nuclear Information System (INIS)

    Since 2003, a severe form of H5N1 avian influenza has rapidly spread throughout Asia and Europe, infecting over 200 humans in 10 countries. The spread of H5N1 virus from person-to-person has been rare, thus preventing the emergence of a widespread pandemic. However, this ongoing epidemic continues to pose an important public health threat. Avian flu and its pandemic potential in humans will be discussed.

  19. A Field Guide to Outdoor Learning in Powell County, Biome Descriptions, Field Activities, Field Sites.

    Science.gov (United States)

    Powell County High School, Deer Lodge, MT.

    Serving as a guide to the outdoor areas of Powell County, Montana, and the surrounding area, this resource book is useful for teachers who wish to explore the out-of-doors with their students, particularly those interested in nature studies. Its aim is to produce a citizenry that is knowledgeable concerning the biophysical environment and its…

  20. Analysis of viral protein-2 encoding gene of avian encephalomyelitis virus from field specimens in Central Java region, Indonesia

    Directory of Open Access Journals (Sweden)

    Aris Haryanto

    2016-01-01

    Full Text Available Aim: Avian encephalomyelitis (AE is a viral disease which can infect various types of poultry, especially chicken. In Indonesia, the incidence of AE infection in chicken has been reported since 2009, the AE incidence tends to increase from year to year. The objective of this study was to analyze viral protein 2 (VP-2 encoding gene of AE virus (AEV from various species of birds in field specimen by reverse transcription polymerase chain reaction (RT-PCR amplification using specific nucleotides primer for confirmation of AE diagnosis. Materials and Methods: A total of 13 AEV samples are isolated from various species of poultry which are serologically diagnosed infected by AEV from some areas in central Java, Indonesia. Research stage consists of virus samples collection from field specimens, extraction of AEV RNA, amplification of VP-2 protein encoding gene by RT-PCR, separation of RT-PCR product by agarose gel electrophoresis, DNA sequencing and data analysis. Results: Amplification products of the VP-2 encoding gene of AEV by RT-PCR methods of various types of poultry from field specimens showed a positive results on sample code 499/4/12 which generated DNA fragment in the size of 619 bp. Sensitivity test of RT-PCR amplification showed that the minimum concentration of RNA template is 127.75 ng/μl. The multiple alignments of DNA sequencing product indicated that positive sample with code 499/4/12 has 92% nucleotide homology compared with AEV with accession number AV1775/07 and 85% nucleotide homology with accession number ZCHP2/0912695 from Genbank database. Analysis of VP-2 gene sequence showed that it found 46 nucleotides difference between isolate 499/4/12 compared with accession number AV1775/07 and 93 nucleotides different with accession number ZCHP2/0912695. Conclusions: Analyses of the VP-2 encoding gene of AEV with RT-PCR method from 13 samples from field specimen generated the DNA fragment in the size of 619 bp from one sample with

  1. Nonlinear evolution of electron shear flow instabilities in the presence of an external guide magnetic field

    CERN Document Server

    Jain, Neeraj

    2016-01-01

    The dissipation mechanism by which the magnetic field reconnects in the presence of an external (guide) magnetic field in the direction of the main current is not well understood. In thin electron current sheets (ECS) (thickness ~ an electron inertial length) formed in collisionless magnetic reconnection, electron shear flow instabilities (ESFI) are potential candidates for providing an anomalous dissipation mechanism which can break the frozen-in condition of the magnetic field affecting the structure and rate of reconnection. We investigate the evolution of ESFI in guide field magnetic reconnection. The properties of the resulting plasma turbulence and their dependence on the strength of the guide field are studied. Utilizing 3-D electron-magnetohydrodynamic simulations of ECS we show that, unlike the case of ECS self-consistently embedded in anti-parallel magnetic fields, the evolution of thin ECS in the presence of a guide field (equal to the asymptotic value of the reconnecting magnetic field or larger) ...

  2. On the Electron Agyrotropy during Rapid Asymmetric Magnetic Island Coalescence in Presence of a Guide Field

    CERN Document Server

    Cazzola, Emanuele; Goldman, Martin V; Newman, David L; Markidis, Stefano; Lapenta, Giovanni

    2016-01-01

    We present an analysis of the properties of the electron velocity distribution during island coalescence in asymmetric reconnection with and without guide field. In a previous study, three main domains were identified, in the case without guide field, as X-, D- and M-regions featuring different reconnection evolutions {Cazzola et al. 2015). These regions are also identified here in the case with guide field. We study the departure from isotropic and gyrotropic behavior by means of different robust detection algorithms proposed in the literature. While in the case without guide field these metrics show an overall agreement, when the guide field is present a discrepancy in the agyrotropy within some relevant regions is observed, such as at the separatrices and inside magnetic islands. Moreover, in light of the new observations from the Multiscale MagnetoSpheric mission, an analysis of the electron velocity phase-space in these domains is presented.

  3. Avian Influenza

    OpenAIRE

    Tsung-Zu Wu; Li-Min Huang

    2005-01-01

    Influenza is an old disease but remains vital nowadays. Three types of influenza viruses,namely A, B, C, have been identified; among them influenza A virus has pandemic potential.The first outbreak of human illness due to avian influenza virus (H5N1) occurred in1997 in Hong Kong with a mortality of 30%. The most recent outbreak of the avian influenzaepidemic has been going on in Asian countries since 2003. As of March 2005, 44 incidentalhuman infections and 32 deaths have been documented. Hum...

  4. Study on propagation properties of laser guiding EMP in a finite magnetic field

    International Nuclear Information System (INIS)

    The geometric model of laser plasma channel (LPC) guiding electromagnetic pulse (EMP) in a finite electromagnetic field is created; when LPC is in lossy gas the propagation properties of the normal modes of LPC guiding EMP are studied; and then the wave equation of longitudinal electormagnetic field and the relationship between transverse and longitudinal electromagnetic field in anisotropic medium are derived under the generalized cylindrical coordinate system. By applying the boundary conditions of electromagnetic fields, the strict characteristic equation of mode propagation for LPC guiding EMP is deduced, and the effects of plasma parameters, surrounding material and external magnetic field on propagation are discussed. The results show that the propagation properties of magnetized LPC guiding EMP are easy to be controlled compared with those without external magnetic field or an infinite external magnetic field applied. (authors)

  5. Tridimensional to bidimensional transition in magnetohydrodynamic turbulence with guiding field and kinetic helicity injection

    CERN Document Server

    Sujovolsky, N E

    2016-01-01

    We study the transition in dimensionality of a three-dimensional magnetohydrodynamic flow forced only mechanically, when the strength of a magnetic guiding field is gradually increased. We use numerical simulations to consider cases in which the mechanical forcing injects (or not) helicity in the flow. As the guiding field is increased, the strength of the magnetic field fluctuations decrease as a power law of the guiding field intensity. We show that for strong enough guiding fields, the helical magnetohydrodynamic flow can become almost two-dimensional. In this case, the mechanical energy can undergo a process compatible with an inverse cascade, being transferred preferentially towards scales larger than the forcing scale. The presence of helicity changes the spectral scaling of the small magnetic field fluctuations, and affects the statistics of the velocity field and of the velocity gradients. Moreover, at small scales the dynamics of the flow becomes dominated by a direct cascade of helicity, which can b...

  6. Variation-Aware Design of Custom Integrated Circuits A Hands-on Field Guide A Hands-on Field Guide

    CERN Document Server

    McConaghy, Trent; Dyck, Jeffrey; Gupta, Amit

    2013-01-01

    This book targets custom IC designers who are encountering variation issues in their designs, especially for modern process nodes at 45nm and below, such as statistical process variations, environmental variations, and layout effects.  The authors have created a field guide to show how to handle variation proactively, and to understand the benefits of doing so. Readers facing variation challenges in their memory, standard cell, analog/RF, and custom digital designs will find easy-to-read, pragmatic solutions.   Reviews the most important concepts in variation-aware design, including types of variables and variation, useful variation-aware design terminology, and an overview and comparison of high-level design flows. Describes and compares a suite of approaches and flows for PVT corner-driven design and verification. Presents Fast PVT, a novel, confidence-driven global optimization technique for PVT corner extraction and verification that is both rapid and reliable. Presents a visually-oriented overview of ...

  7. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  8. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>Aims and Scope Avian Research is an open access,peer-reviewed journal publishing high quality research and review articles on all aspects of ornithology from all over the world.It aims to report the latest and most significant progress in ornithology and to encourage exchange of ideas among international ornithologists.As an Open Access journal,

  9. The Scaling of Electron Acceleration in Magnetic Reconnection with a Guide Field

    CERN Document Server

    Dahlin, J T; Swisdak, M

    2016-01-01

    Kinetic simulations of two-dimensional collisionless magnetic reconnection with a guide field reveal disparate behavior in the weak and strong guide field regimes. In systems where the guide field is smaller than the reconnecting component, the dominant electron accelerator is a Fermi-type mechanism that preferentially energizes the most energetic particles. In the strong guide field regime, however, the field-line contraction that drives Fermi reflection becomes weak. Instead, parallel electric fields ($E_\\parallel$) are primarily responsible for driving electron heating but are ineffective in driving the energetic component of the spectrum. This is due to the the weaker energy scaling of acceleration by $E_\\parallel$ compared with Fermi reflection. These results have important implications for understanding electron acceleration in solar flares and reconnection-driven dissipation in astrophysical turbulence.

  10. Suppressing decoherence of spin waves in a warm atomic vapor by applying a guiding magnetic field

    International Nuclear Information System (INIS)

    We report an experimental and theoretical investigation to extend lifetimes of light storages by applying guiding magnetic fields in a room-temperature atomic vapor. The storages are based on dynamic electromagnetically induced transparency. Retrieval efficiencies versus storage time are experimentally measured for different strengths of the guiding magnetic fields. The measured results show that the 1/e storage times are ∼6 μs and ∼59 μs for the guiding field B0z = 0 and B0z = 93 mG, respectively. Physical processes causing decoherence in an atomic ensemble have been discussed and analyzed. A theory model which is used to evaluate the decoherence caused by fluctuations of transverse magnetic fields is developed. Based on this evaluation, the fact that storage lifetimes can be increased by applying guiding magnetic fields is well explained. (paper)

  11. The Onset of Ion Heating During Magnetic Reconnection with a Strong Guide Field

    CERN Document Server

    Drake, J F

    2014-01-01

    The onset of the acceleration of ions during magnetic reconnection is explored via particle-in-cell simulations in the limit of a strong ambient guide field that self-consistently and simultaneously follow the motions of protons and $\\alpha$ particles. Heating parallel to the local magnetic field during reconnection with a guide field is strongly reduced compared with the reconnection of anti-parallel magnetic fields. The dominant heating of thermal ions during guide field reconnection results from pickup behavior of ions during their entry into reconnection exhausts and dominantly produces heating perpendicular rather than parallel to the local magnetic field. Pickup behavior requires that the ion transit time across the exhaust boundary (with a transverse scale of the order of the ion sound Larmor radius) be short compared with the ion cyclotron period. This translates into a threshold in the strength of reconnecting magnetic field that favors the heating of ions with high mass-to-charge. A simulation with ...

  12. Electronic Field Guides and User Communities in the Eco-informatics Revolution

    Directory of Open Access Journals (Sweden)

    Robert Morris

    2003-07-01

    Full Text Available The recognition that taxonomy is central to the conservation of biodiversity has reestablished the critical role of taxonomy in biology. However, many of the tools taxonomists produce for the identification and characterization of species, e.g., dichotomous keys, have been difficult to use and largely ignored by the general public in favor of field guides, which are essentially browsable picture guides. We review the role of field guides in species identification and discuss the application of a host of digital technologies to produce user-friendly tools for identification that are likely to greatly enhance species identification in the field by nonspecialists. We suggest that wider adoption of the citizen science model and the use of electronic field guides will enhance public understanding and participation in biodiversity monitoring.

  13. Illustrated field guide to the Lahontan Valley wetlands flora, Churchill County, Nevada

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The illustrated field guide to wetland and adjacent upland (transitional) plants has been designed to aid the layperson in identification of the more common species...

  14. Simulation of the relativistic backward wave oscillator with a sinusoidal guiding magnetic field

    Institute of Scientific and Technical Information of China (English)

    MA Qiao-Sheng; FAN Zhi-Kai; ZHOU Chuan-Ming

    2009-01-01

    A simulation is carried out to investigate a relativistic backward wave oscillator (RBWO) with a sinusoidal guiding magnetic field. In the numerical simulation, a microwave output power of 1.33 GW at 9.57 GHz microwave frequency with 33% conversion efficiency is achieved. It is a significant attempt which is helpful for developing a practical high power microwave (HPM) source guided by a permanent magnetic field.

  15. Mode field expansion in index-guiding microstructured optical fibers

    Science.gov (United States)

    Sharma, Dinesh Kumar; Sharma, Anurag

    2013-05-01

    The mode-field expander (MFE) is a microstructured optical fiber (MOF) based device that enlarges the modal field distribution and can couple light from large mode area (LMA) fibers into small core fibers or vice-versa and other optical waveguides. Using our earlier developed analytical field model, we studied the mode-field expansion in MOFs having triangular lattice, and low-loss splicing of MOFs to standard single-mode fibers (SMFs), based on the controlled all airhole collapse method, which leads to an optimum mode-field match at the joint interface of the MOF-SMF. Comparisons with available experimental and simulation results have also been included.

  16. Micro-instabilities and anomalous transport effects in collisionless guide field reconnection

    Science.gov (United States)

    Munoz Sepulveda, Patricio Alejandro; Büchner, Jörg; Kilian, Patrick

    2016-07-01

    It is often the case that magnetic reconnection takes place in collisionless plasmas with a current aligned guide magnetic field, such as in the Solar corona. The general characteristics of this process have been exhaustively analyzed with theory and numerical simulations, under different approximations, since some time ago. However, some consequences and properties of the secondary instabilities arising spontaneously -other than tearing instability-, and their dependence on the guide field strength, have not been completely understood yet. For this sake, we use the results of fully kinetic 2D PIC numerical simulations of guide field reconnection. By using a mean field approach for the Generalized Ohm's law that explains the balance of the reconnected electric field, we find that some of the cross-streaming and gradient driven instabilities -in the guide field case- produce an additional anomalous transport term. The latter can be interpreted as a result of the enhanced correlated electromagnetic fluctuations, leading to a slow down of the current carriers and kinetic scale turbulence. We characterize these processes on dependence on the guide field strength, and explore the causal relation with the source of free energy driving the mentioned instabilities. Finally, we show the main consequences that a fully 3D approach have on all those phenomena in contrast to the reduced 2D description.

  17. Avian influenza

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2006-06-01

    Full Text Available Avian influenza, or “bird flu”, is a contagious disease of animals which crossed the species barrier to infect humans and gave a quite impact on public health in the world since 2004, especially due to the threat of pandemic situation. Until 1st March 2006, laboratory-confirmed human cases have been reported in seven countries: Cambodia, Indonesia, Thailand, Viet Nam, China, Iraq and Turkey with a total of 174 cases and 94 dead (54.02%. Indonesia has 27 cases, 20 were dead (74.07%. AI cases in Indonesia are more in male (62.5% and all have a symptom of fever. An influenza pandemic is a rare but recurrent event. An influenza pandemic happens when a new subtype emerges that has not previously circulated in humans. For this reason, avian H5N1 is a strain with pandemic potential, since it might ultimately adapt into a strain that is contagious among humans. Impact of the pandemic could include high rates of illness and worker absenteeism are expected, and these will contribute to social and economic disruption. Historically, the number of deaths during a pandemic has varied greatly. Death rates are largely determined by four factors: the number of people who become infected, the virulence of the virus, the underlying characteristics and vulnerability of affected populations, and the effectiveness of preventive measures. Accurate predictions of mortality cannot be made before the pandemic virus emerges and begins to spread. (Med J Indones 2006; 15:125-8Keywords: Avian Influenza, Pandemic

  18. Field Guide to Marine Ecology of Kenyan Coast.

    OpenAIRE

    2000-01-01

    This guide introduces you to a model of Kenyan coast: from sandy shore across a lagoon of shallow water with sea grass and coral garden, out to the flinging reef where the waves break and the coral rises like a wall from the depths of the ocean. The beach and lagoon are in a marine park where shells, plants, fish and other marine life is protected. In the marine ecosystem here there are 6 habitats, which have their own plants and animals that adapted to the particular environment.

  19. Avian Influenza

    OpenAIRE

    Tjandra Y. Aditama

    2008-01-01

    Avian influenza, or “bird flu”, is a contagious disease of animals which crossed the species barrier to infect humans and gave a quite impact on public health in the world since 2004, especially due to the threat of pandemic situation. Until 1st March 2006, laboratory-confirmed human cases have been reported in seven countries: Cambodia, Indonesia, Thailand, Viet Nam, China, Iraq and Turkey with a total of 174 cases and 94 dead (54.02%). Indonesia has 27 cases, 20 were dead (74.07%). AI cases...

  20. Avian influenza virus in pregnancy.

    Science.gov (United States)

    Liu, Shelan; Sha, Jianping; Yu, Zhao; Hu, Yan; Chan, Ta-Chien; Wang, Xiaoxiao; Pan, Hao; Cheng, Wei; Mao, Shenghua; Zhang, Run Ju; Chen, Enfu

    2016-07-01

    The unprecedented epizootic of avian influenza viruses, such as H5N1, H5N6, H7N1 and H10N8, has continued to cause disease in humans in recent years. In 2013, another novel influenza A (H7N9) virus emerged in China, and 30% of those patients died. Pregnant women are particularly susceptible to avian influenza and are more likely to develop severe complications and to die, especially when infection occurs in the middle and late trimesters. Viremia is believed to occur infrequently, and thus vertical transmission induced by avian influenza appears to be rare. However, avian influenza increases the risk of adverse pregnancy outcomes, including spontaneous abortion, preterm birth and fatal distress. This review summarises 39 cases of pregnant women and their fetuses from different countries dating back to 1997, including 11, 15 and 13 infections with H7N9, H5N1 and the 2009 pandemic influenza (H1N1), respectively. We analysed the epidemic features, following the geographical, population and pregnancy trimester distributions; underlying diseases; exposure history; medical timelines; human-to-human transmission; pathogenicity and vertical transmission; antivirus treatments; maternal severity and mortality and pregnancy outcome. The common experiences reported in different countries and areas suggest that early identification and treatment are imperative. In the future, vigilant virologic and epidemiologic surveillance systems should be developed to monitor avian influenza viruses during pregnancy. Furthermore, extensive study on the immune mechanisms should be conducted, as this will guide safe, rational immunomodulatory treatment among this high-risk population. Most importantly, we should develop a universal avian influenza virus vaccine to prevent outbreaks of the different subtypes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27187752

  1. Geologic field-trip guide to Lassen Volcanic National Park and vicinity, California

    Science.gov (United States)

    Muffler, L. J. Patrick; Clynne, Michael A.

    2015-07-22

    This geologic field-trip guide provides an overview of Quaternary volcanism in and around Lassen Volcanic National Park in northern California. The guide begins with a comprehensive overview of the geologic framework and the stratigraphic terminology of the Lassen region, based primarily on the “Geologic map of Lassen Volcanic National Park and vicinity” (Clynne and Muffler, 2010). The geologic overview is then followed by detailed road logs describing the volcanic features that can readily be seen in the park and its periphery. Twenty-one designated stops provide detailed explanations of important volcanic features. The guide also includes mileage logs along the highways leading into the park from the major nearby communities. The field-trip guide is intended to be a flexible document that can be adapted to the needs of a visitor approaching the park from any direction.

  2. Quantum field theory a tourist guide for mathematicians

    CERN Document Server

    Folland, Gerald B

    2008-01-01

    Quantum field theory has been a great success for physics, but it is difficult for mathematicians to learn because it is mathematically incomplete. Folland, who is a mathematician, has spent considerable time digesting the physical theory and sorting out the mathematical issues in it. Fortunately for mathematicians, Folland is a gifted expositor. The purpose of this book is to present the elements of quantum field theory, with the goal of understanding the behavior of elementary particles rather than building formal mathematical structures, in a form that will be comprehensible to mathematicians. Rigorous definitions and arguments are presented as far as they are available, but the text proceeds on a more informal level when necessary, with due care in identifying the difficulties. The book begins with a review of classical physics and quantum mechanics, then proceeds through the construction of free quantum fields to the perturbation-theoretic development of interacting field theory and renormalization theor...

  3. Moonwalk with Your Eyes A Pocket Field Guide

    CERN Document Server

    Plotner, Tammy

    2010-01-01

    Are you ready to take a quarter of a million mile journey with just your eyes? Then welcome to "Moon Walk with Your Eyes"! We often take the beauty of our nearest astronomical neighbor for granted. How often do we really stop to think about why it looks the way it does or what a closer look will reveal? In this book, written in easy-to-understand language by one backyard astronomer to another, we'll explore the Moon night by night, as it goes through a full cycle. Every lunar day has something new to learn! And along your journey, you will be reading about the history, mystery, poetry, and legends that are associated with our Moon. Charts will help guide you to specific lunar features, as well as annotated photographic maps that pinpoint important or unusual craters. You'll soon learn to identify major features at just a glance and be able to create your own world-class images. You'll have right at hand the times and dates for every lunar day, phase, and eclipse for years to come. Imagine yourself at the tele...

  4. The Beginner's Guide to Interactive Virtual Field Trips

    Science.gov (United States)

    Zanetis, Jan

    2010-01-01

    For students, field trips can be the best of both worlds: a welcome and exciting break from day-to-day classroom activities and a memorable, real-world experience that will solidify the curriculum in their minds. Unfortunately, the most desirable trips--those to far-away, enticing destinations--have long been inaccessible to all but a select few,…

  5. Prediction and near-field observation of skull-guided acoustic waves

    OpenAIRE

    Estrada, Héctor; Rebling, Johannes; Razansky, Daniel

    2016-01-01

    Ultrasound waves propagating in water or soft biological tissue are strongly reflected when encountering the skull, which limits the use of ultrasound-based techniques in transcranial imaging and therapeutic applications. Current knowledge on the acoustic properties of the cranial bone is restricted to far-field observations, leaving its near-field properties unexplored. We report on the existence of skull-guided acoustic waves, which was herein confirmed by near-field measurements of optoaco...

  6. A Visual Astronomer's Photographic Guide to the Deep Sky A Pocket Field Guide

    CERN Document Server

    Rumistrzewicz, Stefan

    2010-01-01

    How many times have you ‘found’ a deep sky object (DSO), ticked it off the list, and moved on, or used the ‘Tour’ function on your GO-TO ‘scope and said, ‘Oh that’s a just a smudge’ or ‘Can’t see it – I’ll move on to the next one.’ If this has happened to you, then this book is for you. It will challenge you to go back to the ‘smudge’ and really look. Can you see the faint wisp or the detail in the southeastern corner? Can you see the small cluster within the cluster? Try to classify the open cluster for yourself. Compare it to the ‘accepted’ Trumpler classification. Whether you have a GO-TO ‘scope or not, this book gets you to rediscover one of the great things that got you into this hobby in the first place – looking through the eyepiece of a telescope. So pack away the DSLR, CCD camera, the guide ‘scope, and laptop and open your pencil case! You’re in for some fun!

  7. The Deep Change Field Guide A Personal Course to Discovering the Leader Within

    CERN Document Server

    Quinn, Robert E

    2012-01-01

    How to realize your own leadership potential Based on the bestselling book, Deep Change, The Deep Change Field Guide takes readers through the introspective journey of personal transformation. The field guide streamlines, updates, and augments the content of the original book into an interactive self-teaching course that helps readers learn how to become powerful agents of change. Learning tools include reflection questions, film assignments, and action plans that help readers think about the concepts in terms of their own situations, and identify actions to embody the concepts in their lives.

  8. Linux malware incident response an excerpt from malware forensic field guide for Linux systems

    CERN Document Server

    Malin, Cameron H; Aquilina, James M

    2013-01-01

    Linux Malware Incident Response is a ""first look"" at the Malware Forensics Field Guide for Linux Systems, exhibiting the first steps in investigating Linux-based incidents. The Syngress Digital Forensics Field Guides series includes companions for any digital and computer forensic investigator and analyst. Each book is a ""toolkit"" with checklists for specific tasks, case studies of difficult situations, and expert analyst tips. This compendium of tools for computer forensics analysts and investigators is presented in a succinct outline format with cross-references to suppleme

  9. A Field Evaluation of the Time-of-Detection Method to Estimate Population Size and Density for Aural Avian Point Counts

    Directory of Open Access Journals (Sweden)

    Mathew W. Alldredge

    2007-12-01

    Full Text Available The time-of-detection method for aural avian point counts is a new method of estimating abundance, allowing for uncertain probability of detection. The method has been specifically designed to allow for variation in singing rates of birds. It involves dividing the time interval of the point count into several subintervals and recording the detection history of the subintervals when each bird sings. The method can be viewed as generating data equivalent to closed capture–recapture information. The method is different from the distance and multiple-observer methods in that it is not required that all the birds sing during the point count. As this method is new and there is some concern as to how well individual birds can be followed, we carried out a field test of the method using simulated known populations of singing birds, using a laptop computer to send signals to audio stations distributed around a point. The system mimics actual aural avian point counts, but also allows us to know the size and spatial distribution of the populations we are sampling. Fifty 8-min point counts (broken into four 2-min intervals using eight species of birds were simulated. Singing rate of an individual bird of a species was simulated following a Markovian process (singing bouts followed by periods of silence, which we felt was more realistic than a truly random process. The main emphasis of our paper is to compare results from species singing at (high and low homogenous rates per interval with those singing at (high and low heterogeneous rates. Population size was estimated accurately for the species simulated, with a high homogeneous probability of singing. Populations of simulated species with lower but homogeneous singing probabilities were somewhat underestimated. Populations of species simulated with heterogeneous singing probabilities were substantially underestimated. Underestimation was caused by both the very low detection probabilities of all distant

  10. Near-to-far field transformations for radiative and guided waves

    CERN Document Server

    Yang, Jianji; Lalanne, Philippe

    2015-01-01

    Light emitters or scatterers embedded in stratified media may couple energy to both free space and guided modes of the stratified structure. For a thorough analysis of such structures, it is important to evaluate the angular intensity distribution of both the free-space-propagative and guided waves. In this work, we propose an original method based on Lorentz-reciprocity theorem and on the computation of the near-field around the emitters or scatterers, to efficiently calculate the free-space and guided radiation diagrams with a high accuracy. We also provide an open-source code that may be used with virtually any Maxwells solver. The numerical tool may help to engineer various devices, such as light-emitting diodes or nanoantennas to achieve directional and efficient radiative spontaneous decays in free space and guided optics.

  11. A Novel Electrostatic Guiding Scheme for Cold Polar Molecules in Weak-Field-Seeking States

    Institute of Scientific and Technical Information of China (English)

    DENG Lian-Zhong; XIA Yong; YIN Jian-Ping

    2005-01-01

    @@ We propose a novel electrostatic guiding scheme for cold polar molecules in weak-field-seeking states using a single charged wire half embanked in a ceramic substrate (i.e., a chip) and a homogeneous bias electric field, which is produced by a capacitor composed of two large parallel metal plates. We calculate the spatial distribution of the electrostatic fields generated by the combination of the charged wire and the plate capacitor and the corresponding trapping potentials for CO molecules, and analyse the relationships between the electric field and the parameters of the charged-wire layout. Our study shows that the proposed scheme with a single charged-wire can be used to guide cold polar molecules in the weak-field-seeking states, and has some potential applications in construction of various molecule-optical elements.

  12. On the Electron Diffusion Region in Asymmetric Reconnection with a Guide Magnetic Field

    Science.gov (United States)

    Hesse, Michael; Liu, Yi-Hsin; Chen, Li-Jen; Bessho, Naoki; Kuznetsova, Masha; Birn, Joachim; Burch, James L.

    2016-01-01

    Particle-in-cell simulations in a 2.5-D geometry and analytical theory are employed to study the electron diffusion region in asymmetric reconnection with a guide magnetic field. The analysis presented here demonstrates that similar to the case without guide field, in-plane flow stagnation and null of the in-plane magnetic field are well separated. In addition, it is shown that the electric field at the local magnetic X point is again dominated by inertial effects, whereas it remains dominated by nongyrotropic pressure effects at the in-plane flow stagnation point. A comparison between local electron Larmor radii and the magnetic gradient scale lengths predicts that distribution should become nongyrotropic in a region enveloping both field reversal and flow stagnation points. This prediction is verified by an analysis of modeled electron distributions, which show clear evidence of mixing in the critical region.

  13. Field detection of avian influenza virus in wild birds: evaluation of a portable rRT-PCR system and freeze-dried reagents

    Science.gov (United States)

    Takekawa, John Y.; Iverson, Samuel A.; Schultz, Annie K.; Hill, Nichola J.; Cardona, Carol J.; Boyce, Walter M.; Dudley, Joseph P.

    2010-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAIV) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds is often conducted in remote regions, but results are often delayed because of limited local analytical capabilities, difficulties with sample transportation and permitting, or problems keeping samples cold in the field. In response to these challenges, the performance of a portable real-time, reverse transcriptase-polymerase chain reaction (rRT-PCR) unit (RAPID(Registered), Idaho Technologies, Salt Lake City, UT) that employed lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies) was compared to virus isolation combined with real-time RT-PCR conducted in a laboratory. This study included both field and experimental-based sampling. Field samples were collected from migratory shorebirds captured in northern California, while experimental samples were prepared by spiking fecal material with an H6N2 AIV isolate. Results indicated that the portable rRT-PCR unit had equivalent specificity to virus isolation with no false positives, but sensitivity was compromised at low viral titers. Use of portable rRT-PCR with lyophilized reagents may expedite surveillance results, paving the way to a better understanding of wild bird involvement in HPAIV H5N1 transmission.

  14. Avian respiratory system disorders

    Science.gov (United States)

    Olsen, G.H.

    1989-01-01

    Diagnosing and treating respiratory diseases in avian species requires a basic knowledge about the anatomy and physiology of this system in birds. Differences between mammalian and avian respiratory system function, diagnosis, and treatment are highlighted.

  15. Avian Influenza in Birds

    Science.gov (United States)

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza in Birds Language: English Español Recommend on ...

  16. Avian Influenza (Bird Flu)

    Science.gov (United States)

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... this? Submit Button Past Newsletters Information on Avian Influenza Language: English Español Recommend on Facebook Tweet ...

  17. The Six-Inch Lunar Atlas A Pocket Field Guide

    CERN Document Server

    Spain, Don

    2009-01-01

    The Six-Inch Lunar Atlas has been designed specifically for use in the field by lunar observers so it’s perfect for fitting into an observer’s pocket! The author’s own lunar photographs were taken with a 6-inch (150mm) telescope and CCD camera, and closely match the visual appearance of the Moon when viewed through 3-inch to 8-inch telescopes. Each picture is shown oriented "as the Moon really is" when viewed from the northern hemisphere, and is supplemented by exquisite computer sketches that list the main features. Two separate computer sketches are provided to go with each photograph, one oriented to appear as seen through an SCT telescope (e.g. the Meade and Celestron ranges), the other oriented for Newtonian and refracting telescopes. Observers using the various types telescopes will find it extremely helpful to identify lunar features as the human brain is very poor at making "mirror-image" visual translations.

  18. Field trip guide to the Valles Caldera and its geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Goff, F.E.; Bolivar, S.L.

    1983-12-01

    This field trip guide has been compiled from extensive field trips led at Los Alamos National Laboratory during the past six years. The original version of this guide was designed to augment a workshop on the Valles Caldera for the Continental Scientific Drilling Program (CSDP). This workshop was held at Los Alamos, New Mexico, 5-7 October 1982. More stops were added to this guide to display the volcanic and geothermal features at the Valles Caldera. The trip covers about 90 miles (one way) and takes two days to complete; however, those who wish to compress the trip into one day are advised to use the designated stops listed in the Introduction. Valles Caldera and vicinity comprise both one of the most exciting geothermal areas in the United States and one of the best preserved Quaternary caldera complexes in the world.

  19. Field trip guide to selected outcrops, Arbuckle Mountains, Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-11-17

    The Arbuckle Mountains, named for Brigadier General Matthew Arbuckle, are located in south-central Oklahoma. The formations that comprise the Arbuckle Mountains have been extensively studied for hydrocarbon source rock and reservoir rock characteristics that can be applied to the subsurface in the adjacent Anadarko and Ardmore basins. Numerous reports and guidebooks have been written concerning the Arbuckle Mountains. A few important general publications are provided in the list of selected references. The purpose of this handout is to provide general information on the geology of the Arbuckle Mountains and specific information on the four field trip stops, adapted from the literature. The four stops were at: (1) Sooner Rock and Sand Quarry; (2) Woodford Shale; (3) Hunton Anticline and Hunton Quarry; and (4) Tar Sands of Sulfur Area. As part of this report, two papers are included for more detail: Paleomagnetic dating of basinal fluid migration, base-metal mineralization, and hydrocarbon maturation in the Arbuckle Mountains, Oklahoma and Laminated black shale-bedded chert cyclicity in the Woodford Formation, southern Oklahoma.

  20. The Mechanisms of Electron Acceleration During Multiple X Line Magnetic Reconnection with a Guide Field

    CERN Document Server

    Wang, Huanyu; Huang, Can; Wang, Shui

    2016-01-01

    The interactions between magnetic islands are considered to play an important role in electron acceleration during magnetic reconnection. In this paper, two-dimensional (2-D) particle-in-cell (PIC) simulations are performed to study electron acceleration during multiple X line reconnection with a guide field. The electrons remain almost magnetized, and we can then analyze the contributions of the parallel electric field, Fermi and betatron mechanisms to electron acceleration during the evolution of magnetic reconnection by comparing with a guide-center theory. The results show that with the proceeding of magnetic reconnection, two magnetic islands are formed in the simulation domain. The electrons are accelerated by both the parallel electric field in the vicinity of the X lines and Fermi mechanism due to the contraction of the two magnetic islands. Then the two magnetic islands begin to merge into one, and in such a process electrons can be accelerated by the parallel electric field and betatron mechanisms. ...

  1. Operation of Wastewater Treatment Plants: A Field Study Training Program. Volume III, Instructor's Guide. Second Edition.

    Science.gov (United States)

    California State Univ., Sacramento. Dept. of Civil Engineering.

    The objective of this instructor's guide is to help provide students with knowledge and skills for employment in the field of wastewater treatment. Included in each chapter outline are: (1) objectives, (2) instructional approach, (3) answers to the objective test in the student's text, and (4) an explanation of these answers. The material…

  2. Operation of Wastewater Treatment Plants: A Field Study Training Program. Volume II, Instructor's Guide. Second Edition.

    Science.gov (United States)

    California State Univ., Sacramento. Dept. of Civil Engineering.

    The objective of this instructor's guide is to help provide students with knowledge and skills for employment in the field of wastewater treatment. Included in each chapter outline are: (1) objectives, (2) instructional approach, (3) answers to the objective test in the student's text, and (4) an explanation of these answers. The material…

  3. Operation of Wastewater Treatment Plants: A Field Study Training Program. Volume I, Instructor's Guide. Second Edition.

    Science.gov (United States)

    California State Univ., Sacramento. Dept. of Civil Engineering.

    The objective of this instructor's guide is to help provide students with knowledge and skills for employment in the field of wastewater treatment. Included in each chapter outline are: (1) objectives, (2) instructional approach, (3) answers to the objective test in the student's text, and (4) an explanation of these answers. The material…

  4. Quarry Quest. A Field Trip Guide to the Indiana Limestone District, Monroe and Lawrence Counties, Indiana.

    Science.gov (United States)

    Shewmaker, Sherman N.

    This guide provides information for planning a field trip to the Indiana Limestone District. This district, located in Monroe and Lawrence Counties, Indiana, is responsible for material that has dominated the building-limestone market in the United States for nearly a century. A few of the many well-known buildings using Indiana limestone are the…

  5. Electron beam guiding by external magnetic fields in imploded fuel plasma

    Science.gov (United States)

    Johzaki, T.; Sentoku, Y.; Nagatomo, H.; Sunahara, A.; Sakagami, H.; Fujioka, S.; Shiraga, H.; Endo, T.; FIREX project Group

    2016-05-01

    For enhancing the core heating efficiency in fast ignition laser fusion, we proposed the fast electron beam by externally-applied the kilo-tesla (kT) class longitudinal magnetic field. We evaluated the imploded core and the magnetic field profiles formed through the implosion dynamics by resistive MHD radiation hydro code. Using those profiles, the guiding effect was evaluated by fast electron transport simulations, which shows that in addition to the feasible field configuration (moderate mirror ratio), the kT-class magnetic field is required at the fast electron generation point. In this case, the significant enhancement in heating efficiency is expected.

  6. Revision of the IOC/ITST Post-Tsunami Field Guide (Invited)

    Science.gov (United States)

    Dengler, L. A.; IOC/ITST Core Working Group on the Post-Tsunami Field Guide

    2010-12-01

    A small international working group of tsunami researchers met at the AGU Meeting of the Americas in August 2010 to update and revise the Intergovernmental Oceanographic Coimmission (IOC) Manual & Guides no. 37 “Post-Tsunami Field Guide”. The original guide was published by the IOC in 1998. The developments in the tsunami field and the expansion of tsunami science into disciplines not originally covered in the 1998 document led the IOC Tsunami Unit to convene a working group to update and accommodate new areas not covered in the original document. Recent tsunami disasters indicated the necessity of assessing comprehensive social factors such as resilience and vulnerability and measuring the impacts on the environment and ecosystem. The revised guide attempts to balance the needs of the scientific community to measure perishable data in the immediate aftermath of a tsunami event and the individual/community/governmental issues involved with response and recovery. The guide will also incorporate lessons learned from the IOC/ITST coordination of the response to the recent tsunamis in Samoa and Chile. A draft of the revised skeleton of the guide will be presented at the meeting and members of the tsunami research community will be invited to comment.

  7. Construction of Specialty Guide Field Coils Using an Industrial Robotic Arm

    Science.gov (United States)

    Berry, William; Crawford, Christopher; Fugal, Mario; Martin, Elise; Wagner, Daniel; Milburn, Robert

    2011-10-01

    Many contemporary nuclear physics experiments require precise control of the magnetic field within key regions of the experimental apparatus. The nEDM experiment, for instance, requires uniform guide fields (produced by guide field coils) to transport neutron spin polarization from the polarizer to the measurement cell. Guide field coils in general are subject to tight geometrical constraints, and must not produce any external fields which would affect the results of the experiment. In order to produce a satisfactory coil in light of these constraints, a systematic design technique is needed. We introduce the magnetic scalar potential technique, which calculates the exact coil windings required on a specified boundary to produce any desired field distribution inside that satisfies Maxwell's equations. Realizing the designs produced by this technique introduces an additional difficulty: winding many turns according to the exact calculated paths. This is addressed by ``printing'' our coils onto a copper-plated G10 form using a calibrated robot arm and spindle, resulting in a 3-d printed circuit board. To correct for deviations in the actual shape of the form, we use a laser displacement sensor to capture the actual geometry as input into the calculation of the windings. Supported in part by NSF grant PHY-0855584.

  8. THE MECHANISMS OF ELECTRON ACCELERATION DURING MULTIPLE X LINE MAGNETIC RECONNECTION WITH A GUIDE FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huanyu; Lu, Quanming; Huang, Can; Wang, Shui, E-mail: qmlu@ustc.edu.cn [CAS Key Lab of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China)

    2016-04-20

    The interactions between magnetic islands are considered to play an important role in electron acceleration during magnetic reconnection. In this paper, two-dimensional particle-in-cell simulations are performed to study electron acceleration during multiple X line reconnection with a guide field. Because the electrons remain almost magnetized, we can analyze the contributions of the parallel electric field, Fermi, and betatron mechanisms to electron acceleration during the evolution of magnetic reconnection through comparison with a guide-center theory. The results show that with the magnetic reconnection proceeding, two magnetic islands are formed in the simulation domain. Next, the electrons are accelerated by both the parallel electric field in the vicinity of the X lines and the Fermi mechanism due to the contraction of the two magnetic islands. Then, the two magnetic islands begin to merge into one, and, in such a process, the electrons can be accelerated by both the parallel electric field and betatron mechanisms. During the betatron acceleration, the electrons are locally accelerated in the regions where the magnetic field is piled up by the high-speed flow from the X line. At last, when the coalescence of the two islands into one big island finishes, the electrons can be further accelerated by the Fermi mechanism because of the contraction of the big island. With the increase of the guide field, the contributions of the Fermi and betatron mechanisms to electron acceleration become less and less important. When the guide field is sufficiently large, the contributions of the Fermi and betatron mechanisms are almost negligible.

  9. Guiding Neutral Atoms with Two Current-Carrying Wires and a Vertical Bias Field on the Atom Chip

    Institute of Scientific and Technical Information of China (English)

    KE Min; YAN Bo; LI Xiao-Lin; WANG Yu-Zhu

    2008-01-01

    @@ We demonstrate the guiding of neutral atoms with two parallel microfabricated current-carrying wires on the atom chip and a verticai magnetic bias field.The atoms are guided along a magnetic field minimum parallel to the current-carrying wires and confined in the other two directions.We describe in detail how the precooled atoms are efficiently loaded into the two-wire guide.

  10. Prediction and near-field observation of skull-guided acoustic waves

    CERN Document Server

    Estrada, Héctor; Razansky, Daniel

    2016-01-01

    Ultrasound waves propagating in water or soft biological tissue are strongly reflected when encountering the skull, which limits the use of ultrasound-based techniques in transcranial imaging and therapeutic applications. Current knowledge on the acoustic properties of the cranial bone is restricted to far-field observations, leaving its near-field properties unexplored. We report on the existence of skull-guided acoustic waves, which was herein confirmed by near-field measurements of optoacoustically-induced responses in ex-vivo murine skulls immersed in water. Dispersion of the guided waves was found to reasonably agree with the prediction of a multilayered flat plate model. It is generally anticipated that our findings may facilitate and broaden the application of ultrasound-mediated techniques in brain diagnostics and therapy.

  11. Cancellation properties in Hall magnetohydrodynamics with a strong guide magnetic field.

    Science.gov (United States)

    Martin, L N; De Vita, G; Sorriso-Valvo, L; Dmitruk, P; Nigro, G; Primavera, L; Carbone, V

    2013-12-01

    We present a signed measure analysis of compressible Hall magnetohydrodynamic turbulence with an external guide field. Signed measure analysis allows us to characterize the scaling behavior of the sign-oscillating flow structures and their geometrical properties (fractal dimensions of structures). A reduced numerical model, valid when a strong guide magnetic field is present, is used here. In order to discuss the effect of the Hall term, different values for the ion skin depth are considered in the simulations. Results show that as the Hall term is increased, the fractal dimension of the current and vorticity sheets decreases. This observation, together with previous analysis of the same fields, provides a comprehensive description of the effect of the Hall force on the formation of structures. Two main processes are identified, namely, the widening and unraveling of the sheets. PMID:24483577

  12. 3D MHD Simulations of Laser Plasma Guiding in Curved Magnetic Field

    Science.gov (United States)

    Roupassov, S.; Rankin, R.; Tsui, Y.; Capjack, C.; Fedosejevs, R.

    1999-11-01

    The guiding and confinement of laser produced plasma in a curved magnetic field has been investigated numerically. These studies were motivated by experiments on pulsed laser deposition of diamond-like films [1] in which a 1kG magnetic field in a curved solenoid geometry was utilized to steer a carbon plasma around a curved trajectory and thus to separate it from unwanted macroparticles produced by the laser ablation. The purpose of the modeling was to characterize the plasma dynamics during the propagation through the magnetic guide field and to investigate the effect of different magnetic field configurations. A 3D curvilinear ADI code developed on the basis of an existing Cartesian code [2] was employed to simulate the underlying resistive one-fluid MHD model. Issues such as large regions of low background density and nonreflective boundary conditions were addressed. Results of the simulations in a curved guide field will be presented and compared to experimental results. [1] Y.Y. Tsui, D. Vick and R. Fedosejevs, Appl. Phys. Lett. 70 (15), pp. 1953-57, 1997. [2] R. Rankin, and I. Voronkov, in "High Performance Computing Systems and Applications", pp. 59-69, Kluwer AP, 1998.

  13. Field guide to geologic excursions in southwestern Utah and adjacent areas of Arizona and Nevada

    Science.gov (United States)

    Lund, William R.; Lund, William R.

    2002-01-01

    This field guide contains road logs for field trips planned in conjunction with the 2002 Rocky Mountain Section meeting of the Geological Society of America held at Southern Utah University in Cedar City, Utah. There are a total of eight field trips, covering various locations and topics in southwestern Utah and adjacent areas of Arizona and Nevada. In addition, the field guide contains a road log for a set of Geological Engineering Field Camp Exercises run annually by the University of Missouri at Rolla in and around Cedar City. Two of the field trips address structural aspects of the geology in southwestern Utah and northwestern Arizona; two trips deal with ground water in the region; and along with the Field Camp Exercises, one trip, to the Grand Staircase, is designed specifically for educators. The remaining trips examine the volcanology and mineral resources of a large area in and around the Tusher Mountains in Utah; marine and brackish water strata in the Grand Staircase-Escalante National Monument; and the Pine Valley Mountains, which are cored by what may be the largest known laccolith in the world. The "Three Corners" area of Utah, Arizona, and Nevada is home to truly world-class geology, and I am confident that all of the 2002 Rocky Mountain Section meeting attendees will find a field trip suited to their interests.

  14. Self-Guided Field Explorations: Integrating Earth Science into Students' Lives

    Science.gov (United States)

    Kirkby, K. C.; Kirkby, S.

    2013-12-01

    Self-guided field explorations are a simple way to transform an earth science class into a more pedagogically effective experience. Previous experience demonstrated that self-guided student explorations of museum and aquarium exhibits were both extremely popular and remarkably effective. That success led our program to test an expansion of the concept to include self-guided student explorations in outdoor field settings. Preliminary assessment indicates these self-guided field explorations are nearly as popular with students as the museum and aquarium explorations and are as pedagogically effective. Student gains on post-instruction assessment match or exceed those seen in instructor-assisted, hands-on, small group laboratory activities and completely eclipse gains achieved by traditional lecture instruction. As importantly, self-guided field explorations provide a way to integrate field experiences into large enrollment courses where the sheer scale of class trips makes them logistically impossible. This expands course breadth, integrating new topics that could not be as effectively covered by the original class structure. Our introductory program assessed two models of self-guided field explorations. A walking/cycling exploration of the Saint Anthony Falls area, a mile from campus, focuses on the intersections of geological processes with human history. Students explore the geology behind the waterfalls' evolution as well as its subsequent social and economic impacts on human history. A second exploration focuses on the campus area geology, including its building stones as well as its landscape evolution. In both explorations, the goal was to integrate geology with the students' broader understanding of the world they live in. Although the explorations' creation requires a significant commitment, once developed, self-guided explorations are surprisingly low maintenance. These explorations provide a model of a simple, highly effective pedagogical tool that is

  15. Vaccine Efficacy Against a New Avian Influenza (H9N2) Field Isolate from the Middle East (Serology and Challenge Studies).

    Science.gov (United States)

    Gharaibeh, Saad; Amareen, Shadi

    2016-05-01

    Avian influenza subtype H9N2 is endemic in many countries in the Middle East. The reported prevalence of infection was variable between countries and ranged from 28.7% in Tunisia to 71% in Jordan. Several commercial killed whole-virus vaccine products are used as monovalent or bivalent mixed with Newcastle disease virus. Recently, we have noticed that many of the vaccinated broiler flocks did not show a production advantage over nonvaccinated flocks in the field. A new avian influenza field virus (H9N2) was isolated from these vaccinated and infected broiler flocks in 2013. This virus had 89.1% similarity of its hemagglutinin (HA) gene to the classical virus used for manufacturing the classical vaccine. Inactivated autogenous vaccine was manufactured from this new field isolate to investigate its serological response and protection in specific-pathogen-free (SPF) and breeder-male chickens compared to the classical vaccine. Oropharyngeal virus shedding of vaccinated breeder-male chickens was evaluated at 3, 9, 10, and 14 days postchallenge (DPC). Percentage of chickens shedding the virus at 3 DPC was 64%, 50%, and 64% in the classical vaccine group, autogenous vaccine group, and the control challenged group, respectively. At 7 DPC percentage of virus shedding was 42%, 7%, and 64% in the classical vaccine group, autogenous vaccine group, and the control challenged group, respectively. At 10 DPC only 9% of classical vaccine group was shedding the virus and there was no virus shedding in any of the groups at 14 DPC. There was statistical significance difference (P < 0.05) in shedding only at 7 DPC between the autogenous vaccine group and the other two groups. At 42 days of age (14 DPC), average body weight was 2.720, 2.745, 2.290, and 2.760 kg for the classical vaccine group, autogenous vaccine group, control challenged group, and control unchallenged group, respectively. Only the control challenged group had significantly (P < 0.05) lower average body weight. In

  16. Rapid diagnosis of avian influenza virus in wild birds: Use of a portable rRT-PCR and freeze-dried reagents in the field

    Science.gov (United States)

    Takekawa, J.Y.; Hill, N.J.; Schultz, A.K.; Iverson, S.A.; Cardona, C.J.; Boyce, W.M.; Dudley, J.P.

    2011-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

  17. Natural guide-star processing for wide-field laser-assisted AO systems

    CERN Document Server

    Correia, Carlos M; Conan, Jean-Marc; Petit, Cyril; Sauvage, Jean-Francois; Fusco, Thierry; Vernet, Joel D R; Thatte, Niranjan

    2016-01-01

    Sky-coverage in laser-assisted AO observations largely depends on the system's capability to guide on the faintest natural guide-stars possible. Here we give an up-to-date status of our natural guide-star processing tailored to the European-ELT's visible and near-infrared (0.47 to 2.45 {\\mu}m) integral field spectrograph - Harmoni. We tour the processing of both the isoplanatic and anisoplanatic tilt modes using the spatio-angular approach whereby the wave-front is estimated directly in the pupil plane avoiding a cumbersome explicit layered estimation on the 35-layer profiles we're currently using. Taking the case of Harmoni, we cover the choice of wave-front sensors, the number and field location of guide-stars, the optimised algorithms to beat down angular anisoplanatism and the performance obtained with different temporal controllers under split high-order/low-order tomography or joint tomography. We consider both atmospheric and far greater telescope wind buffeting disturbances. In addition we provide the...

  18. Field guide on reduction and disposal of waste from oil refineries and marketing installations

    Energy Technology Data Exchange (ETDEWEB)

    Dando, D.A.J.; Bossand, B.; Lilie, R.H.; Ooms, A.C.; Sutherland, H.

    1990-07-01

    The field guide has been written primarily for those in the oil refining and marketing industry who have responsibility for the management of waste and its disposal. It should also provide useful information to the authorities who exercise legal control over these activities. It lists the types of wastes commonly encountered in the industry and highlights techniques for minimizing the quantities generated. Guidance is given on the methods of pre-treatment and disposal, together with information on how to select and monitor waste facilities and contractors, to ensure a high quality and safe disposal operation. Information is also provided on documentation and labelling of waste cargoes, and reference is made to legislation and sources of additional information. While use of the field guide cannot guarantee a problem-free operation, it will minimize the risks involved in disposal of waste materials from oil industry installations.

  19. The double-gradient magnetic instability: Stabilizing effect of the guide field

    Energy Technology Data Exchange (ETDEWEB)

    Korovinskiy, D. B., E-mail: daniil.korovinskiy@gmail.com; Semenov, V. S.; Ivanova, V. V. [Saint Petersburg State University, 198504, Ulyanovskaya 1, Petrodvoretz (Russian Federation); Divin, A. V. [Saint Petersburg State University, 198504, Ulyanovskaya 1, Petrodvoretz (Russian Federation); Swedish Institute of Space Physics, SE-751 21 Uppsala (Sweden); Erkaev, N. V. [Institute of Computational Modelling, Russian Academy of Sciences, Siberian Branch, 660036 Krasnoyarsk (Russian Federation); Siberian Federal University, 660041 Krasnoyarsk (Russian Federation); Artemyev, A. V. [Space Research Institute RAS, Profsoyuznaya 84/32, Moscow 117997 (Russian Federation); Ivanov, I. B. [Saint Petersburg State University, 198504, Ulyanovskaya 1, Petrodvoretz (Russian Federation); Theoretical Physics Division, Petersburg Nuclear Physics Institute, 188300 Gatchina (Russian Federation); Lapenta, G. [Centrum voor Plasma-Astrofysica, Departement Wiskunde, Katholieke Universiteit Leuven, B-3001 Leuven (Belgium); Markidis, S. [PDC Center for High Performance Computing, KTH Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Biernat, H. K. [Space Research Institute, Austrian Academy of Sciences, 8042 Graz (Austria); Institute of Physics, University of Graz, 8010 Graz (Austria)

    2015-01-15

    The role of the dawn-dusk magnetic field component in stabilizing of the magnetotail flapping oscillations is investigated in the double-gradient model framework (Erkaev et al., Phys. Rev. Lett. 99, 235003 (2007)), extended for the magnetotail-like configurations with non-zero guide field B{sub y}. Contribution of the guide field is examined both analytically and by means of linearized 2-dimensional (2D) and non-linear 3-dimensional (3D) MHD modeling. All three approaches demonstrate the same properties of the instability: stabilization of current sheet oscillations for short wavelength modes, appearing of the typical (fastest growing) wavelength λ{sub peak} of the order of the current sheet width, decrease of the peak growth rate with increasing B{sub y} value, and total decay of the mode for B{sub y}∼0.5 in the lobe magnetic field units. Analytical solution and 2D numerical simulations claim also the shift of λ{sub peak} toward the longer wavelengths with increasing guide field. This result is barely visible in 3D simulations. It may be accounted for the specific background magnetic configuration, the pattern of tail-like equilibrium provided by approximated solution of the conventional Grad-Shafranov equation. The configuration demonstrates drastically changing radius of curvature of magnetic field lines, R{sub c}. This, in turn, favors the “double-gradient” mode (λ > R{sub c}) in one part of the sheet and classical “ballooning” instability (λ < R{sub c}) in another part, which may result in generation of a “combined” unstable mode.

  20. Standard guide for data fields for computerized transfer of digital radiological examination data

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This guide provides a listing and description of the fields that are recommended for inclusion in a digital radiological examination data base to facilitate the transfer of such data. This guide sets guidelines for the format of data fields for computerized transfer of digital image files obtained from radiographic, radioscopic, computed radiographic, or other radiological examination systems. The field listing includes those fields regarded as necessary for inclusion in the data base: (1) regardless of the radiological examination method (as indicated by Footnote C in Table 1), (2) for radioscopic examination (as indicated by Footnote E in Table 1), and (3) for radiographic examination (as indicated by Footnote D in Table 1). In addition, other optional fields are listed as a reminder of the types of information that may be useful for additional understanding of the data or applicable to a limited number of applications. 1.2 It is recognized that organizations may have in place an internal format for the...

  1. Two-dimensional behavior of three-dimensional magnetohydrodynamic flow with a strong guiding field.

    Science.gov (United States)

    Alexakis, Alexandros

    2011-11-01

    The magnetohydrodynamic (MHD) equations in the presence of a guiding magnetic field are investigated by means of direct numerical simulations. The basis of the investigation consists of nine runs forced at the small scales. The results demonstrate that for a large enough uniform magnetic field the large scale flow behaves as a two-dimensional (2D) (non-MHD) fluid exhibiting an inverse cascade of energy in the direction perpendicular to the magnetic field, while the small scales behave like a three-dimensional (3D) MHD fluid cascading the energy forwards. The amplitude of the inverse cascade is sensitive to the magnetic field amplitude, the domain size, the forcing mechanism, and the forcing scale. All these dependences are demonstrated by the varying parameters of the simulations. Furthermore, in the case that the system is forced anisotropically in the small parallel scales an inverse cascade in the parallel direction is observed that is feeding the 2D modes k(//)=0.

  2. Experiments on the effects of global force balance and local reconnection physics on magnetic reconnection with a guide field

    Science.gov (United States)

    Fox, W.; Sciortino, F.; Yoo, J.; Jara-Almonte, J.; Na, B.; Ji, H.; Yamada, M.

    2015-11-01

    In many plasma environments ranging from astrophysics to fusion, magnetic reconnection occurs with a finite guide field ranging from a fraction to many times the upstream reconnecting component. Theory and simulation yields a range of predictions of scaling of the rate of reconnection with guide field. Recent experiments on the Magnetic Reconnection Experiment observed a systematic decrease in reconnection rates with increasing guide field. Here we present a new set of experimental results on MRX with a controlled applied guide magnetic field ranging from 0 to approximately 3 times the upstream reconnection field, where we observe both global and local processes which affect the reconnection rate in the guide field regime. First, we observe and quantify the effects of global force balance, in particular global back pressure due to pileup of magnetic field in the downstream, which decreases the outflow of plasma from the current sheet and hence the reconnection rate. Second, we study the role of electron pressure in the generalized Ohm's law in the guide field regime and its role in setting the reconnection rate.

  3. Guided resonances on lithium niobate for extremely small electric field detection investigated by accurate sensitivity analysis.

    Science.gov (United States)

    Qiu, Wentao; Ndao, Abdoulaye; Lu, Huihui; Bernal, Maria-Pilar; Baida, Fadi Issam

    2016-09-01

    We present a theoretical study of guided resonances (GR) on a thin film lithium niobate rectangular lattice photonic crystal by band diagram calculations and 3D Finite Difference Time Domain (FDTD) transmission investigations which cover a broad range of parameters. A photonic crystal with an active zone as small as 13μm×13μm×0.7μm can be easily designed to obtain a resonance Q value in the order of 1000. These resonances are then employed in electric field (E-field) sensing applications exploiting the electro optic (EO) effect of lithium niobate. A local field factor that is calculated locally for each FDTD cell is proposed to accurately estimate the sensitivity of GR based E-field sensor. The local field factor allows well agreement between simulations and reported experimental data therefore providing a valuable method in optimizing the GR structure to obtain high sensitivities. When these resonances are associated with sub-picometer optical spectrum analyzer and high field enhancement antenna design, an E-field probe with a sensitivity of 50 μV/m could be achieved. The results of our simulations could be also exploited in other EO based applications such as EEG (Electroencephalography) or ECG (Electrocardiography) probe and E-field frequency detector with an 'invisible' probe to the field being detected etc. PMID:27607627

  4. Attomolar detection of influenza A virus hemagglutinin human H1 and avian H5 using glycan-blotted field effect transistor biosensor.

    Science.gov (United States)

    Hideshima, Sho; Hinou, Hiroshi; Ebihara, Daisuke; Sato, Ryosuke; Kuroiwa, Shigeki; Nakanishi, Takuya; Nishimura, Shin-Ichiro; Osaka, Tetsuya

    2013-06-18

    Influenza virus, through cell invasion and propagation with the interaction between hemagglutinin (HA) present on its surface and glycans on the host cell, causes a rapidly spreading infection throughout the world. In the present investigation, we succeeded for the first time in the attomolar-level sensing and discrimination of influenza A viral HA molecules H1 and H5 by using a glycan-immobilized field effect transistor (FET) biosensor. The small ligand glycans immobilized on the FET device, which make effective use of the charge-detectable region for FET-based detection in terms of Debye length, gave an advantage in the highly sensitive detection of the proteins. Two kinds of trisaccharides receptors terminating in sialic acid-α2,6-galactose (6'-sialyllactose) and in sialic acid-α2,3-galactose (3'-sialyllactose) were conjugated directly with the SiO2 surface of FET devices by a simple glycoblotting method using the self-assembled monolayer (SAM) of aminooxy terminated silane-coupling reagent, 3-aminooxypropyltriethoxysilane. Furthermore, it was demonstrated that the FETs with densely immobilized glycans, which possess the high capture ability by achieving the glycoside cluster effect, clearly distinguish HA molecules between their subtypes H1 (human) and H5 (avian) at the attomolar level, while the conventional method based on HA antibodies achieves only picomolar-level detection. Our findings indicate that the glycan-immobilized FET is a promising device to detect various pathogenic bacteria and viruses through glycan-protein interaction found ubiquitously in many infectious diseases. PMID:23675869

  5. Sub-solar Magnetopause Observation and Simulation of a Tripolar Guide-Magnetic Field Perturbation

    Science.gov (United States)

    Eriksson, S.; Cassak, P.; Retino, A.; Mozer, F.

    2015-12-01

    The Polar satellite recorded two reconnection exhausts within 6 min on 1 April 2001 at a rather symmetric sub-solar magnetopause that displayed different out-of-plane signatures for similar solar wind conditions. The first case was reported by Mozer et al. [2002] and displayed a bipolar guide field supporting a quadrupole Hall field consistent with a single X-line. The second case, however, shows the first known example of a tripolar guide-field perturbation at Earth's magnetopause reminiscent of the types of solar wind exhausts that Eriksson et al. [2014; 2015] have reported to be in agreement with multiple X-lines. A dedicated particle-in-cell simulation is performed for the prevailing conditions across the magnetopause. We propose an explanation in terms of asymmetric Hall magnetic fields due to a presence of a magnetic island between two X-lines, and discuss how higher resolution MMS observations can be used to further study this problem at the magnetopause.

  6. Image-guided spinal injection procedures in open high-field MRI with vertical field orientation: feasibility and technical features

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, F.; Walter, T.; Wonneberger, U.; Wagner, M.; Hermann, K.G.; Hamm, B.; Teichgraeber, U. [Charite, Humboldt-Universitaet zu Berlin, Department of Radiology, Berlin (Germany); Chopra, S. [Charite-Universitaetsmedizin Berlin, Campus Virchow Klinikum, Department of General, Visceral, and Transplantation Surgery, Berlin (Germany); Wichlas, F. [Charite-Universitaetsmedizin Berlin, Campus Virchow Klinikum, Center for Musculoskeletal Surgery, Berlin (Germany)

    2010-02-15

    We prospectively evaluated the feasibility and technical features of MR-guided lumbosacral injection procedures in open high-field MRI at 1.0 T. In a CuSO{sub 4}.5H{sub 2}O phantom and five human cadaveric spines, fluoroscopy sequences (proton-density-weighted turbo spin-echo (PDw TSE), T1w TSE, T2w TSE; balanced steady-state free precession (bSSFP), T1w gradient echo (GE), T2w GE) were evaluated using two MRI-compatible 20-G Chiba-type needles. Artefacts were analysed by varying needle orientation to B{sub 0}, frequency-encoding direction and slice orientation. Image quality was described using the contrast-to-noise ratio (CNR). Subsequently, a total of 183 MR-guided nerve root (107), facet (53) and sacroiliac joint (23) injections were performed in 53 patients. In vitro, PDw TSE sequence yielded the best needle-tissue contrasts (CNR = 45, 18, 15, 9, and 8 for needle vs. fat, muscle, root, bone and sclerosis, respectively) and optimal artefact sizes (width and tip shift less than 5 mm). In vivo, PDw TSE sequence was sufficient in all cases. The acquisition time of 2 s facilitated near-real-time MRI guidance. Drug delivery was technically successful in 100% (107/107), 87% (46/53) and 87% (20/23) of nerve root, facet and sacroiliac joint injections, respectively. No major complications occurred. The mean procedure time was 29 min (range 19-67 min). MR-guided spinal injections in open high-field MRI are feasible and accurate using fast TSE sequence designs. (orig.)

  7. Comparative genomics reveals insights into avian genome evolution and adaptation

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Cai; Li, Qiye;

    2014-01-01

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, ...

  8. Microwave generation from an axially extracted virtual cathode oscillator with a guide magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kostov, K.G.; Nikolov, N.A. (Department of General Physics, Sofia University, Sofia 1126 (Bulgaria))

    1994-04-01

    The operation of a virtual cathode oscillator (vircator) with strong axial magnetic field has been experimentally studied. Depending on the cathode--anode gap and cathode diameter, the operating voltage varies from 200 kV up to 480 kV with 2--7 kA diode current. Microwave emission is produced by the oscillating virtual cathode. The central microwave frequency follows the beam plasma frequency. It varies by 11.5 GHz up to 22 GHz, depending on the current density. The oscillation frequency does not depend on the guide magnetic field magnitude. A maximal output power of 15[plus minus]5 MW in asymmetric transverse magnetic (TM) modes is achieved by the axially extracted vircator. Variation of the magnetic field intensity in a range of 0--40 kG has an insignificant effect upon the emitted microwave power. An electron beam power to microwave power conversion efficiency of approximately 1% is obtained.

  9. Microwave generation from an axially extracted virtual cathode oscillator with a guide magnetic field

    International Nuclear Information System (INIS)

    The operation of a virtual cathode oscillator (vircator) with strong axial magnetic field has been experimentally studied. Depending on the cathode--anode gap and cathode diameter, the operating voltage varies from 200 kV up to 480 kV with 2--7 kA diode current. Microwave emission is produced by the oscillating virtual cathode. The central microwave frequency follows the beam plasma frequency. It varies by 11.5 GHz up to 22 GHz, depending on the current density. The oscillation frequency does not depend on the guide magnetic field magnitude. A maximal output power of 15±5 MW in asymmetric transverse magnetic (TM) modes is achieved by the axially extracted vircator. Variation of the magnetic field intensity in a range of 0--40 kG has an insignificant effect upon the emitted microwave power. An electron beam power to microwave power conversion efficiency of approximately 1% is obtained

  10. A new approach for field instrumentation in grouted rock bolt monitoring using guided ultrasonic waves

    Science.gov (United States)

    Zou, D. H.; Cui, Y.

    2011-11-01

    A rock bolt installed in the field for ground support has only one short exposed end on the rock surface. This condition has posed challenges in field instrumentation. In this paper, a new approach for field monitoring of grouted rock bolts using guided ultrasonic waves is proposed with the receiving transducer on the grout surface near the exposed end of the bolt. The effects of the receiver location are studied with numerical modeling. A location correction factor is introduced to correlate the amplitude ratio along the bolt and that on the grout surface. Experiments are conducted to verify the modeling results. This research indicates that it is practically possible to receive meaningful signals with the receiver on the grout surface and that with the recorded data the attenuation and wave velocity of guided waves in grouted rock bolts can be determined with reasonable accuracy. The proper receiver location is found to be 27 to 32 mm from the bolt center for the test condition.

  11. New Edition of the UNESCO-IOC International Tsunami Survey Team (ITST) Post-Tsunami Survey Field Guide

    Science.gov (United States)

    Dengler, L.; Dominey-Howes, D.; Yamamoto, M.; Borrero, J. C.; Dunbar, P. K.; Fritz, H. M.; Imamura, F.; Kong, L. S.; Koshimura, S.; McAdoo, B. G.; Satake, K.; Yalciner, A. C.; Yulianto, E.

    2011-12-01

    A subcommittee of the IUGG International Tsunami Commission was convened in 2010 to revise and update the 1998 UNESCO-IOC Post-Tsunami Survey Field Guide. The revised Guide addresses the developments in the tsunami field since 1998, the need to accommodate vastly increased amounts of data, and to incorporate disciplines that were not covered in the original guide. The Guide also advocates a systems-approach to assessing tsunami impacts that examines the full range of physical, environmental, and socio-economic effects and their interrelationship, bringing tsunami research efforts into a closer alignment with the UN International Strategy for Disaster Reduction (UNISDR). This Field Guide is intended to provide a flexible framework to facilitate the acquisition of critical data in the immediate aftermath of significant tsunamis and to balance the needs of international researchers with those of communities and agencies involved with response and recovery. It will be of use to a variety of people and organizations who may either participate in, assist in coordination, or host post-tsunami field surveys. It is hoped that this Guide will promote pre-event planning in countries at risk of tsunamis to reduce the stresses of developing organizational logistics in the post-emergency response phase and make the process of conducting an ITST easier and more productive for both participating researchers and host country organizations. A complete draft of the Guide will be presented at the meeting and members of the tsunami community invited to comment.

  12. Spectral and variational principles of electromagnetic field excitation in wave guides

    Energy Technology Data Exchange (ETDEWEB)

    Yahalom, Asher [College of Judea and Samaria, Ariel 44284 (Israel)]. E-mail: asya@yosh.ac.il; Pinhasi, Yosef [College of Judea and Samaria, Ariel 44284 (Israel); Lurie, Yuri [College of Judea and Samaria, Ariel 44284 (Israel)

    2005-08-29

    Possible variational principles for excitation of an electromagnetic field in a wave guide are discussed. Our emphasis is not on the calculation of the modal shapes, which is common in previous art, but rather on the calculation of modal amplitude evolution, which are important in electron devices such as free electron lasers and gyrotrons. Variational principles have considerable importance in theoretical physics and are used among other things to derive numerical solution schemes, conservation laws via the Noether theorem and correct boundary conditions for the derived equations including the important effects of the backward waves amplitudes.

  13. Spectral and variational principles of electromagnetic field excitation in wave guides [rapid communication

    Science.gov (United States)

    Yahalom, Asher; Pinhasi, Yosef; Lurie, Yuri

    2005-08-01

    Possible variational principles for excitation of an electromagnetic field in a wave guide are discussed. Our emphasis is not on the calculation of the modal shapes, which is common in previous art, but rather on the calculation of modal amplitude evolution, which are important in electron devices such as free electron lasers and gyrotrons. Variational principles have considerable importance in theoretical physics and are used among other things to derive numerical solution schemes, conservation laws via the Noether theorem and correct boundary conditions for the derived equations including the important effects of the backward waves amplitudes.

  14. Magnetic-field-induced dose effects in MR-guided radiotherapy systems: dependence on the magnetic field strength.

    Science.gov (United States)

    Raaijmakers, A J E; Raaymakers, B W; Lagendijk, J J W

    2008-02-21

    Several institutes are currently working on the development of a radiotherapy treatment system with online MR imaging (MRI) modality. The main difference between their designs is the magnetic field strength of the MRI system. While we have chosen a 1.5 Tesla (T) magnetic field strength, the Cross Cancer Institute in Edmonton will be using a 0.2 T MRI scanner and the company Viewray aims to use 0.3 T. The magnetic field strength will affect the severity of magnetic field dose effects, such as the electron return effect (ERE): considerable dose increase at tissue air boundaries due to returning electrons. This paper has investigated how the ERE dose increase depends on the magnetic field strength. Therefore, four situations where the ERE occurs have been simulated: ERE at the distal side of the beam, the lateral ERE, ERE in cylindrical air cavities and ERE in the lungs. The magnetic field comparison values were 0.2, 0.75, 1.5 and 3 T. Results show that, in general, magnetic field dose effects are reduced at lower magnetic field strengths. At the distal side, the ERE dose increase is largest for B = 0.75 T and depends on the irradiation field size for B = 0.2 T. The lateral ERE is strongest for B = 3 T but shows no effect for B = 0.2 T. Around cylindrical air cavities, dose inhomogeneities disappear if the radius of the cavity becomes small relative to the in-air radius of the secondary electron trajectories. At larger cavities (r > 1 cm), dose inhomogeneities exist for all magnetic field strengths. In water-lung-water phantoms, the ERE dose increase takes place at the water-lung transition and the dose decreases at the lung-water transition, but these effects are minimal for B = 0.2 T. These results will contribute to evaluating the trade-off between magnetic field dose effects and image quality of MR-guided radiotherapy systems.

  15. Magnetic-field-induced dose effects in MR-guided radiotherapy systems: dependence on the magnetic field strength

    International Nuclear Information System (INIS)

    Several institutes are currently working on the development of a radiotherapy treatment system with online MR imaging (MRI) modality. The main difference between their designs is the magnetic field strength of the MRI system. While we have chosen a 1.5 Tesla (T) magnetic field strength, the Cross Cancer Institute in Edmonton will be using a 0.2 T MRI scanner and the company Viewray aims to use 0.3 T. The magnetic field strength will affect the severity of magnetic field dose effects, such as the electron return effect (ERE): considerable dose increase at tissue air boundaries due to returning electrons. This paper has investigated how the ERE dose increase depends on the magnetic field strength. Therefore, four situations where the ERE occurs have been simulated: ERE at the distal side of the beam, the lateral ERE, ERE in cylindrical air cavities and ERE in the lungs. The magnetic field comparison values were 0.2, 0.75, 1.5 and 3 T. Results show that, in general, magnetic field dose effects are reduced at lower magnetic field strengths. At the distal side, the ERE dose increase is largest for B = 0.75 T and depends on the irradiation field size for B = 0.2 T. The lateral ERE is strongest for B = 3 T but shows no effect for B = 0.2 T. Around cylindrical air cavities, dose inhomogeneities disappear if the radius of the cavity becomes small relative to the in-air radius of the secondary electron trajectories. At larger cavities (r > 1 cm), dose inhomogeneities exist for all magnetic field strengths. In water-lung-water phantoms, the ERE dose increase takes place at the water-lung transition and the dose decreases at the lung-water transition, but these effects are minimal for B = 0.2 T. These results will contribute to evaluating the trade-off between magnetic field dose effects and image quality of MR-guided radiotherapy systems

  16. Exposure of workers to the risks related to electromagnetic fields. Guide for risk assessment

    International Nuclear Information System (INIS)

    This guide aims at helping companies to prevent risks related to worker exposure to electromagnetic fields, and at simplifying the assessment approach. After some generalities of electromagnetic fields (notions of electromagnetic spectrum, electric, magnetic and electromagnetic fields, wavelength and frequency, reactive near- or far-field area, work environment), this report describes the effect of an exposure with respect to frequencies (under 100 khz, over 10 MHz, between 100 khz and 10 MHz), recalls the regulation in occupational environment. It presents some generalities on exposure sources, and methods and ways for a simplified risk assessment (equipment inventory and characterization, CE-labelled equipment). It addresses various aspects of a deepened risk assessment: the exposure assessment (emitted field measurement, workstation analysis, maximum exposure, determination of exposure action level or VDA), the indirect effects (contact with a metallic object within the field, projection of ferromagnetic objects, initiation of firing electric devices, fires and explosions), and workers with specific risks (those bearing active implants or passive ferromagnetic implants, pregnant women). The last part addresses actions aimed at reducing the exposure. Eight industrial applications are more particularly addressed and discussed at the end of each chapter: induction-based devices (welding, fusion, heating, surface treatment, so on), magnetizers and demagnetizers, magneto-scopic devices, magnetic resonance imagery devices, electrolytic cells, heating or welding devices based on dielectric losses, and microwave ovens

  17. Gyrokinetic and kinetic particle-in-cell simulations of guide-field reconnection. I. Macroscopic effects of the electron flows

    International Nuclear Information System (INIS)

    In this work, we compare gyrokinetic (GK) with fully kinetic Particle-in-Cell (PIC) simulations of magnetic reconnection in the limit of strong guide field. In particular, we analyze the limits of applicability of the GK plasma model compared to a fully kinetic description of force free current sheets for finite guide fields (bg). Here, we report the first part of an extended comparison, focusing on the macroscopic effects of the electron flows. For a low beta plasma (βi = 0.01), it is shown that both plasma models develop magnetic reconnection with similar features in the secondary magnetic islands if a sufficiently high guide field (bg ≳ 30) is imposed in the kinetic PIC simulations. Outside of these regions, in the separatrices close to the X points, the convergence between both plasma descriptions is less restrictive (bg ≳ 5). Kinetic PIC simulations using guide fields bg ≲ 30 reveal secondary magnetic islands with a core magnetic field and less energetic flows inside of them in comparison to the GK or kinetic PIC runs with stronger guide fields. We find that these processes are mostly due to an initial shear flow absent in the GK initialization and negligible in the kinetic PIC high guide field regime, in addition to fast outflows on the order of the ion thermal speed that violate the GK ordering. Since secondary magnetic islands appear after the reconnection peak time, a kinetic PIC/GK comparison is more accurate in the linear phase of magnetic reconnection. For a high beta plasma (βi = 1.0) where reconnection rates and fluctuations levels are reduced, similar processes happen in the secondary magnetic islands in the fully kinetic description, but requiring much lower guide fields (bg ≲ 3)

  18. Gyrokinetic and kinetic particle-in-cell simulations of guide-field reconnection

    Science.gov (United States)

    Munoz Sepulveda, Patricio Alejandro; Büchner, Jörg; Kilian, Patrick; Told, Daniel; Jenko, Frank

    2016-07-01

    Fully kinetic Particle-in-Cell (PIC) simulations of (strong) guide-field reconnection can be computationally very demanding, due to the intrinsic stability and accuracy conditions required by this numerical method. One convenient approach to circumvent this issue is using gyrokinetic theory, an approximation of the Vlasov-Maxwell equations for strongly magnetized plasmas that eliminates the fast gyromotion, and thus reduces the computational cost. Although previous works have started to compare the features of reconnection between both approaches, a complete understanding of the differences is far from being complete. This knowledge is essential to discern the limitations of the gyrokinetic simulations of magnetic reconnection when applied to scenarios with moderate guide fields, such as the Solar corona, in contrast to most of the fusion/laboratory plasmas. We extend a previous work by our group, focused in the differences in the macroscopic flows, by analyzing the heating processes and non-thermal features developed by reconnection between both plasma approximations. We relate these processes by identifying some high-frequency cross-streaming instabilities appearing only in the fully kinetic approach. We characterize the effects of these phenonema such as anisotropic electron heating, beam formation and turbulence under different parameter regimes. And finally, we identify the conditions under which these instabilities tends to become negligible in the fully kinetic model, and thus a comparison with gyrokinetic theory becomes more reliable.

  19. A proposal to pulse the Bevatron/Bevalac main guide field magnet with SCR power supplies

    International Nuclear Information System (INIS)

    The Bevatron/Bevalac Main Guide Field Power Supply was originally designed to provide a 15,250 Volt DC. at sign 8400 Ampere peak magnet pulse. Protons were accelerated to 6.2 Gev. The 128 Megawatt (MW) pulse required two large motor-generator (MG) sets with 67 ton flywheels to store 680 Megajoules of energy. Ignitron rectifiers are used to rectify the generator outputs. Acceleration of heavy ions results in an operating schedule with a broad range of peak fields. The maximum field of 12.5 kilogauss requires a peak pulse of 80 MW. Acceleration of ions to 1.0 kilogauss requires an 8 MW peak pulse. One MG set can provide pulses below 45 MW. Peak pulses of less than 15 MW are now a large block of the operating schedule. A proposal has been made to replace the existing MG system with eight SCR power supplies for low field operation. The SCR supplies will be powered directly from the Lawrence Berkeley Laboratory's 12.3 KV. power distribution system. This paper describes the many advantages of the plan. 4 refs., 3 figs., 3 tabs

  20. Editorial: Avian Research

    Institute of Scientific and Technical Information of China (English)

    Yong; Wang; Guangmei; Zheng

    2014-01-01

    <正>Welcome to Avian Research!This new journal is a continuation and enhancement of Chinese Birds,which has been and continues to be sponsored by the China Ornithological Society and Beijing Forestry University.In the four years since its inception,the original journal—the only one in China focusing on avian research—has published over 130 manuscripts,with authors from all continents across the world,garnering global respect in

  1. Avian influenza – Review

    OpenAIRE

    Öner, Ahmet Faik

    2007-01-01

    Recent spread of avian influenza A H5N1 virus to poultry and wild birds has increased the threat of human infections with H5N1 virus worldwide In this review the epidemiology virolgy clinical and laboratory characteristics and management of avian influenza is described The virus has demonsrated considerable pandemic potential and is the most likely candidate of next pandemic threat For pandemic preparedness stockpiling antiviral agents and vaccination are the most important intervention measu...

  2. Avian influenza virus risk assessment in falconry

    OpenAIRE

    Lüschow Dörte; Lierz Peter; Jansen Andreas; Harder Timm; Hafez Hafez; Kohls Andrea; Schweiger Brunhilde; Lierz Michael

    2011-01-01

    Abstract Background There is a continuing threat of human infections with avian influenza viruses (AIV). In this regard falconers might be a potential risk group because they have close contact to their hunting birds (raptors such as falcons and hawks) as well as their avian prey such as gulls and ducks. Both (hunting birds and prey birds) seem to be highly susceptible to some AIV strains, especially H5N1. We therefore conducted a field study to investigate AIV infections in falconers, their ...

  3. Development and testing of an image-guided FT-IR instrument for field spectroscopy

    Science.gov (United States)

    Dai, Xiaobing; Liu, Xiangyan; Liu, Li

    2015-09-01

    Standoff detection, identification and quantification of chemicals require sensitive spectrometers with calibration capabilities. We have developed a compact novel instrument that can not only provide imaging capability, bust also one that provides spectral capability of the field of view (FOV) center under the image-guided. The system employs a Fourier transform infrared (FT-IR) spectrometer, coupled with chalcogenide glass optical fiber, and a specially designed infrared optic lens. A special kit provided by Bruker Optics is connected on the spectrometer to focus the infrared beam from the lens at the entry of the fiber. Its spectral range covers the infrared band from 1850cm-1 to 5000cm-1 and its spectral resolution could be chosen among six selected values 1, 2, 4, 8, 16, 32cm-1. This paper will address the issues of image-guided spectroscopy and will show how an instrument designed for specifically imaging applications can dramatically improve the performance of the system and quality of the data acquired. The benefit of these technologies in spectroscopy can be demonstrated with a system optimally designed for detecting spectral characteristics of moving targets.

  4. Three Questions to Guide Study and Practice in the Information Systems Field

    Directory of Open Access Journals (Sweden)

    JuanQiong Gou

    2014-09-01

    Full Text Available Gaining an understanding of Information Systems and improving IS education has become a serious issue for the IS discipline. Prior to undertaking Management Information Systems (MIS in an MBA course, students sometimes cannot clearly explain exactly what information systems are and what they should do in practice. This paper begins by considering the various influences on the MIS curriculum and some of the conventional approaches to curriculum design, selection and organisation of teaching materials. It then offers an alternative approach by presenting a three question framework for understanding and explaining the IS field. From this basis the paper argues that these three questions can be used to guide the study, teaching and practice of MIS.

  5. Physical processes of driven magnetic reconnection in collisionless plasmas: Zero guide field case

    Science.gov (United States)

    Cheng, C. Z.; Inoue, S.; Ono, Y.; Horiuchi, R.

    2015-10-01

    The key physical processes of the electron and ion dynamics, the structure of the electric and magnetic fields, and how particles gain energy in the driven magnetic reconnection in collisionless plasmas for the zero guide field case are presented. The key kinetic physics is the decoupling of electron and ion dynamics around the magnetic reconnection region, where the magnetic field is reversed and the electron and ion orbits are meandering, and around the separatrix region, where electrons move mainly along the field line and ions move mainly across the field line. The decoupling of the electron and ion dynamics causes charge separation to produce a pair of in-plane bipolar converging electrostatic electric field ( E→ e s ) pointing toward the neutral sheet in the magnetic field reversal region and the monopolar E→ e s around the separatrix region. A pair of electron jets emanating from the reconnection current layer generate the quadrupole out-of-plane magnetic field, which causes the parallel electric field ( E→ || ) from E→ i n d to accelerate particles along the magnetic field. We explain the electron and ion dynamics and their velocity distributions and flow structures during the time-dependent driven reconnection as they move from the upstream to the downstream. In particular, we address the following key physics issues: (1) the decoupling of electron and ion dynamics due to meandering orbits around the field reversal region and the generation of a pair of converging bipolar electrostatic electric field ( E→ e s ) around the reconnection region; (2) the slowdown of electron and ion inflow velocities due to acceleration/deceleration of electrons and ions by E→ e s as they move across the neutral sheet; (3) how the reconnection current layer is enhanced and how the orbit meandering particles are accelerated inside the reconnection region by E→ i n d ; (4) why the electron outflow velocity from the reconnection region reaches super-Alfvenic speed

  6. Image use in field guides and identification keys: review and recommendations

    OpenAIRE

    Leggett, Roxanne; Kirchoff, Bruce K.

    2011-01-01

    Background and aims Although illustrations have played an important role in identification keys and guides since the 18th century, their use has varied widely. Some keys lack all illustrations, while others are heavily illustrated. Even within illustrated guides, the way in which images are used varies considerably. Here, we review image use in paper and electronic guides, and establish a set of best practices for image use in illustrated keys and guides. Scope Our review covers image use in ...

  7. Environmental protection appraisals: a suggested guide for US Department of Energy field organization. Revision 1

    International Nuclear Information System (INIS)

    This manual has been prepared to assist DOE field organizations in conducting environmental protection appraisals of activities at DOE operating-level facilities. Its primary use will be by DOE operations offices in their appraisal of facilities operating under the authority of the Atomic Energy Act. However, the manual can also be used by other DOE field organizations. This manual is organized in modules that parallel those in the internal environmental audit checklist. It is assumed that the contractor is using the guide previously described (Internal Environmental Protection Audits) and that operations office staff members will have the opportunity to review or be cognizant of the contractor's completed internal audit, and other material generated within the facility, in preparation for the appraisal. This manual was developed to facilitate the appraisal process by providing operations office staff with a choice of modules that can be used independently or as a unit. The manual gives guidelines for reviewing information submitted to the operations office before the site visit and for conducting an on-site operating-level appraisal

  8. MR-guided breast radiotherapy: feasibility and magnetic-field impact on skin dose

    Science.gov (United States)

    van Heijst, Tristan C. F.; den Hartogh, Mariska D.; Lagendijk, Jan J. W.; Desirée van den Bongard, H. J. G.; van Asselen, Bram

    2013-09-01

    The UMC Utrecht MRI/linac (MRL) design provides image guidance with high soft-tissue contrast, directly during radiotherapy (RT). Breast cancer patients are a potential group to benefit from better guidance in the MRL. However, due to the electron return effect, the skin dose can be increased in presence of a magnetic field. Since large skin areas are generally involved in breast RT, the purpose of this study is to investigate the effects on the skin dose, for whole-breast irradiation (WBI) and accelerated partial-breast irradiation (APBI). In ten patients with early-stage breast cancer, targets and organs at risk (OARs) were delineated on postoperative CT scans co-registered with MRI. The OARs included the skin, comprising the first 5 mm of ipsilateral-breast tissue, plus extensions. Three intensity-modulated RT techniques were considered (2× WBI, 1× APBI). Individual beam geometries were used for all patients. Specially developed MRL treatment-planning software was used. Acceptable plans were generated for 0 T, 0.35 T and 1.5 T, using a class solution. The skin dose was augmented in WBI in the presence of a magnetic field, which is a potential drawback, whereas in APBI the induced effects were negligible. This opens possibilities for developing MR-guided partial-breast treatments in the MRL.

  9. Guiding of relativistic electron beams in dense matter by longitudinally imposed strong magnetic fields

    CERN Document Server

    Bailly-Grandvaux, M; Bellei, C; Forestier-Colleoni, P; Fujioka, S; Giuffrida, L; Honrubia, J J; Batani, D; Bouillaud, R; Chevrot, M; Cross, J E; Crowston, R; Dorard, S; Dubois, J -L; Ehret, M; Gregori, G; Hulin, S; Kojima, S; Loyez, E; Marques, J -R; Morace, A; Nicolai, Ph; Roth, M; Sakata, S; Schaumann, G; Serres, F; Servel, J; Tikhonchuk, V T; Woolsey, N; Zhang, Z

    2016-01-01

    High-energy-density flows through dense matter are needed for effective progress in the production of laser-driven intense sources of energetic particles and radiation, in driving matter to extreme temperatures creating state regimes relevant for planetary or stellar science as yet inaccessible at the laboratory scale, or in achieving high-gain laser-driven thermonuclear fusion. When interacting at the surface of dense (opaque) targets, intense lasers accelerate relativistic electron beams which transport a significant fraction of the laser energy into the target depth. However, the overall laser-to-target coupling efficiency is impaired by the large divergence of the electron beam, intrinsic to the laser-plasma interaction. By imposing a longitudinal 600T laser-driven magnetic-field, our experimental results show guided >10MA-current of MeV-electrons in solid matter. Due to the applied magnetic field, the transported energy-density and the peak background electron temperature at the 60micron-thick targets re...

  10. Evidence of magnetic field switch-off in Particle In Cell simulations of collisionless magnetic reconnection with guide field

    Science.gov (United States)

    Innocenti, M. E.; Goldman, M. V.; Newman, D. L.; Markidis, S.; Lapenta, G.

    2015-12-01

    The long term evolution of large domain Particle In Cell simulations of collisionless magnetic reconnection is investigated following observations that show two possible outcomes for collisionless reconnection: towards a Petschek-like configuration (Gosling 2007) or towards multiple X points (Eriksson et al. 2014). In the simulations presented here and described in [Innocenti2015*], a mixed scenario develops. At earlier time, plasmoids are emitted, disrupting the formation of Petschek-like structures. Later, an almost stationary monster plasmoid forms, preventing the emission of other plasmoids. A situation reminding of Petschek's switch-off then ensues. Switch-off is obtained through a slow shock / rotational discontinuity (SS/RD) compound structure, with the rotation discontinuity downstreamthe slow shock. Two external slow shocks located in correspondence of the separatrices reduce the in plane tangential component of the magnetic field, but not to zero. Two transitions reminding of rotational discontinuities in the internal part of the exhausts then perform the final switch-off. Both the slow shocks and the rotational discontinuities are characterized as such through the analysis of their Rankine-Hugoniot jump conditions. A moderate guide field is used to suppress the development of the firehose instability in the exhaust that prevented switch off in [Liu2012]. Compound SS/RD structures, with the RD located downstream the SS, have been observed in both the solar wind and the magnetosphere in Wind and Geotail data respectively [Whang1998, Whang2004]. Ion trajectiories across the SS/RD structure are followed and the kinetic origin of the SS/RD structure is investigated. * Innocenti, Goldman, Newman, Markidis, Lapenta, Evidence of magnetic field switch-off in collisionless magnetic reconnection, accepted in Astrophysical Journal Letters, 2015 Acknowledgements: NERSC, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of

  11. Report on field surveys of dragonflies in Hainan, China, and preparation of a field guide to the Odonata of the island

    OpenAIRE

    Reels , Graham

    2010-01-01

    In early 2007, I was invited by Dr. Michael Lau, Head of the China Programme of Kadoorie Farm & Botanic Garden (KFBG), to write a simple guide to the Odo nata of Hainan, China. KFBG is a Hong Kong-based conservation charity orga- nization, with strong links to tropical southern China, and is conducting a project to produce a series of basic fauna and flora field guides for Hainan Island, to be published in English and Chinese, but primarily aimed at older schoolchildren in China. I previously...

  12. Hebbian Plasticity Guides Maturation of Glutamate Receptor Fields In Vivo

    Directory of Open Access Journals (Sweden)

    Dmitrij Ljaschenko

    2013-05-01

    Full Text Available Synaptic plasticity shapes the development of functional neural circuits and provides a basis for cellular models of learning and memory. Hebbian plasticity describes an activity-dependent change in synaptic strength that is input-specific and depends on correlated pre- and postsynaptic activity. Although it is recognized that synaptic activity and synapse development are intimately linked, our mechanistic understanding of the coupling is far from complete. Using Channelrhodopsin-2 to evoke activity in vivo, we investigated synaptic plasticity at the glutamatergic Drosophila neuromuscular junction. Remarkably, correlated pre- and postsynaptic stimulation increased postsynaptic sensitivity by promoting synapse-specific recruitment of GluR-IIA-type glutamate receptor subunits into postsynaptic receptor fields. Conversely, GluR-IIA was rapidly removed from synapses whose activity failed to evoke substantial postsynaptic depolarization. Uniting these results with developmental GluR-IIA dynamics provides a comprehensive physiological concept of how Hebbian plasticity guides synaptic maturation and sparse transmitter release controls the stabilization of the molecular composition of individual synapses.

  13. Hebbian plasticity guides maturation of glutamate receptor fields in vivo.

    Science.gov (United States)

    Ljaschenko, Dmitrij; Ehmann, Nadine; Kittel, Robert J

    2013-05-30

    Synaptic plasticity shapes the development of functional neural circuits and provides a basis for cellular models of learning and memory. Hebbian plasticity describes an activity-dependent change in synaptic strength that is input-specific and depends on correlated pre- and postsynaptic activity. Although it is recognized that synaptic activity and synapse development are intimately linked, our mechanistic understanding of the coupling is far from complete. Using Channelrhodopsin-2 to evoke activity in vivo, we investigated synaptic plasticity at the glutamatergic Drosophila neuromuscular junction. Remarkably, correlated pre- and postsynaptic stimulation increased postsynaptic sensitivity by promoting synapse-specific recruitment of GluR-IIA-type glutamate receptor subunits into postsynaptic receptor fields. Conversely, GluR-IIA was rapidly removed from synapses whose activity failed to evoke substantial postsynaptic depolarization. Uniting these results with developmental GluR-IIA dynamics provides a comprehensive physiological concept of how Hebbian plasticity guides synaptic maturation and sparse transmitter release controls the stabilization of the molecular composition of individual synapses.

  14. Gyrokinetic simulations of 2D magnetic reconnection turbulence in guide fields

    Science.gov (United States)

    Terry, P. W.; Pueschel, M. J.; Jenko, F.; Zweibel, E.; Zhdankin, V.; Told, D.

    2012-10-01

    Following the analyses in [M.J. Pueschel et al., Phys. Plasmas 18, 112102 (2011)], a study of turbulence in driven reconnection is commenced, with a sinusoidal current sheet providing the drive through a Krook-type operator in a bi-periodic box. Simulations with the Gene code cover all relevant physical parameters, allowing for encompassing comparisons with expectations from linear simulations. A central observed feature are coherent circular current structures which may be identified as plasmoids. These objects move randomly in the plane perpendicular to the guide field, and may either disappear again after some time or instead merge with one another---the setup can thus be described as turbulence driven by reconnection, but simultaneously creating its own reconnection. Such merger events are associated with large bursts in the heating rate jE, and display strong non-Maxwellian components of the distribution function in parallel velocity space. The plasmoid energetics are studied, as are their ability to produce populations of fast particles. Statistics of such populations are used to facilitate direct comparisons with astrophysical scenarios of energetic particle production.

  15. Role of Electron Inertia and Reconnection Dynamics in a Stressed X-point Collapse with a Guide-Field

    CERN Document Server

    von der Pahlen, Jan Graf

    2016-01-01

    In previous simulations of collisionless 2D magnetic reconnection it was consistently found that the term in the generalised Ohm's law that breaks the frozen-in condition is the divergence of the electron pressure tensor's non-gyrotropic components. A fully relativistic particle-in-cell (PIC) code was used to model $X$-point collapse with a guide-field in two and three spatial dimensions. We show that in a 2D $X$-point collapse with a guide-field close to the strength of the in-plane field, the increased induced shear flows along the diffusion region lead to a new reconnection regime in which electron inertial terms play a dominant role at the $X$-point. This transition is marked by the emergence of a magnetic island - and hence a second reconnection site - as well as electron flow vortices moving along the current sheet. The reconnection electric field at the $X$-point is shown to exceed all lower guide-field cases for a brief period, indicating a strong burst in reconnection. By extending the simulation to ...

  16. Avian influenza (fowl plague)

    Science.gov (United States)

    Avian influenza (AI) viruses infect domestic poultry and wild birds. In domestic poultry, AI viruses are typically of low pathogenicity (LP) causing subclinical infections, respiratory disease or drops in egg production. However, a few AI viruses cause severe systemic disease with high mortality; ...

  17. Guiding-centre transformation of the radiation-reaction force in a non-uniform magnetic field

    Science.gov (United States)

    Hirvijoki, E.; Decker, J.; Brizard, A. J.; Embréus, O.

    2015-10-01

    > In this paper, we present the guiding-centre transformation of the radiation-reaction force of a classical point charge travelling in a non-uniform magnetic field. The transformation is valid as long as the gyroradius of the charged particles is much smaller than the magnetic field non-uniformity length scale, so that the guiding-centre Lie-transform method is applicable. Elimination of the gyromotion time scale from the radiation-reaction force is obtained with the Poisson-bracket formalism originally introduced by Brizard (Phys. Plasmas, vol. 11, 2004, 4429-4438), where it was used to eliminate the fast gyromotion from the Fokker-Planck collision operator. The formalism presented here is applicable to the motion of charged particles in planetary magnetic fields as well as in magnetic confinement fusion plasmas, where the corresponding so-called synchrotron radiation can be detected. Applications of the guiding-centre radiation-reaction force include tracing of charged particle orbits in complex magnetic fields as well as the kinetic description of plasma when the loss of energy and momentum due to radiation plays an important role, e.g. for runaway-electron dynamics in tokamaks.

  18. Numerical Simulation of Flow Field in Flow-guide Tank of China Advanced Research Reactor

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The flow-guide tank of China advanced research reactor (CARR) is located at the top of the reactor vessel and connected with the inlet coolant pipe. It acts as a reactor inlet coolant distributor and plays an important role in reducing the flow-induced vibration of the internal components of the reactor core. Several designs of the flow-guide tank have been proposed, however, the final design option has to be made after detailed investigation of the velocity profile within the flow-guide tank for each configuration.

  19. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Español Recommend on Facebook Tweet ... A Viruses Avian Influenza A Virus Infections in Humans Although avian influenza A viruses usually do not ...

  20. Field estimation of soil water content. A practical guide to methods, instrumentation and sensor technology

    International Nuclear Information System (INIS)

    During a period of five years, an international group of soil water instrumentation experts were contracted by the International Atomic Energy Agency to carry out a range of comparative assessments of soil water sensing methods under laboratory and field conditions. The detailed results of those studies are published elsewhere. Most of the devices examined worked well some of the time, but most also performed poorly in some circumstances. The group was also aware that the choice of a water measurement technology is often made for economic, convenience and other reasons, and that there was a need to be able to obtain the best results from any device used. The choice of a technology is sometimes not made by the ultimate user, or even if it is, the main constraint may be financial rather than technical. Thus, this guide is presented in a way that allows the user to obtain the best performance from any instrument, while also providing guidance as to which instruments perform best under given circumstances. That said, this expert group of the IAEA reached several important conclusions: (1) the field calibrated neutron moisture meter (NMM) remains the most accurate and precise method for soil profile water content determination in the field, and is the only indirect method capable of providing accurate soil water balance data for studies of crop water use, water use efficiency, irrigation efficiency and irrigation water use efficiency, with a minimum number of access tubes; (2) those electromagnetic sensors known as capacitance sensors exhibit much more variability in the field than either the NMM or direct soil water measurements, and they are not recommended for soil water balance studies for this reason (impractically large numbers of access tubes and sensors are required) and because they are rendered inaccurate by changes in soil bulk electrical conductivity (including temperature effects) that often occur in irrigated soils, particularly those containing

  1. Evaluation of Guiding Device for Downstream Fish Migration with in-Field Particle Tracking Velocimetry and CFD

    Directory of Open Access Journals (Sweden)

    Staffan Lundstrom

    2015-01-01

    Full Text Available The performance of a fish guiding device located just upstream a hydropower plant is scrutinized. The device is designed to redirect surface orientated down-stream migrating fish (smolts away from the turbines towards a spillway that act as a relatively safe fishway. Particles are added up-stream the device and the fraction particles going to the spillway is measured. A two-frame Particle Tracking Velocimetry algorithm is used to derive the velocity field of the water. The experimental results are compared to simulations with CFD. If the smolts move passively as the particles used in the study the guiding device works very well and some modifications may optimize its performance. In-field Particle Tracking Velocimetry is a suitable technique for the current case and the results compare well with numerical simulations.

  2. Guiding center orbit following calculation of edge particle and heat transport in stochastic magnetic field

    OpenAIRE

    Chang, C C; Nishimura, Y; Cheng, C.Z.

    2013-01-01

    Particle and heat transport in tokamak edge is investigated by guiding center orbit following calculation. The guiding center equation is solved for both electrons and ions in the presence of magnetic perturbation. It is suggested that the remnants of the magnetic islands play a role in characterizing the radial transport. The transport coefficient is estimated which also demonstrate local structure in the vicinity of magnetic islands.

  3. Avian mortalities due to transmission line collisions: a review of current estimates and field methods with an emphasis on applications to the Canadian electric network

    Directory of Open Access Journals (Sweden)

    Sébastien Rioux

    2013-12-01

    Full Text Available Birds are vulnerable to collisions with human-made fixed structures. Despite ongoing development and increases in infrastructure, we have few estimates of the magnitude of collision mortality. We reviewed the existing literature on avian mortality associated with transmission lines and derived an initial estimate for Canada. Estimating mortality from collisions with power lines is challenging due to the lack of studies, especially from sites within Canada, and due to uncertainty about the magnitude of detection biases. Detection of bird collisions with transmission lines varies due to habitat type, species size, and scavenging rates. In addition, birds can be crippled by the impact and subsequently die, although crippling rates are poorly known and rarely incorporated into estimates. We used existing data to derive a range of estimates of avian mortality associated with collisions with transmission lines in Canada by incorporating detection, scavenging, and crippling biases. There are 231,966 km of transmission lines across Canada, mostly in the boreal forest. Mortality estimates ranged from 1 million to 229.5 million birds per year, depending on the bias corrections applied. We consider our most realistic estimate, taking into account variation in risk across Canada, to range from 2.5 million to 25.6 million birds killed per year. Data from multiple studies across Canada and the northern U.S. indicate that the most vulnerable bird groups are (1 waterfowl, (2 grebes, (3 shorebirds, and (4 cranes, which is consistent with other studies. Populations of several groups that are vulnerable to collisions are increasing across Canada (e.g., waterfowl, raptors, which suggests that collision mortality, at current levels, is not limiting population growth. However, there may be impacts on other declining species, such as shorebirds and some species at risk, including Alberta’s Trumpeter Swans (Cygnus buccinator and western Canada’s endangered Whooping

  4. An overview on avian influenza

    OpenAIRE

    Nelson Rodrigo da Silva Martins

    2012-01-01

    Avian influenza (AI) is considered an exotic disease in the Brazilian poultry industry, according to the National Avian Health Program (PNSA), with permanent monitoring of domestic, exotic and native avian species. Brazil presents privileged environmental conditions of reduced risk. In addition, all commercial poultry and conservation holdings are registered in state or national inventories and geographically located (GPS) for health control. Poultry health standards are adopted for the confo...

  5. Avian influenza viruses in humans.

    OpenAIRE

    Malik Peiris, J S

    2009-01-01

    Past pandemics arose from low pathogenic avian influenza (LPAI) viruses. In more recent times, highly pathogenic avian influenza (HPAI) H5N1, LPAI H9N2 and both HPAI and LPAI H7 viruses have repeatedly caused zoonotic disease in humans. Such infections did not lead to sustained human-to-human transmission. Experimental infection of human volunteers and seroepidemiological studies suggest that avian influenza viruses of other subtypes may also infect humans. Viruses of the H7 subtype appear to...

  6. SEKILAS TENTANG AVIAN INFLUENZA (AI)

    OpenAIRE

    Fauziah Elytha

    2011-01-01

    Fluburung atau Avian Influenza (AI) adalah penyakit zoonosis fatal dan menular serta dapat menginfeksi semua jenis burung, manusia, babi, kuda dan anjing, Virus Avian Influenza tipe A (hewan) dari keluarga Drthomyxoviridae telah menyerang manusia dan menyebabkan banyak korban meninggal dunia. Saat ini avian Influenza telah menjadi masalah kesehatan global yang sangat serius, termasuk di Indonesia. Sejak Juli 2005 Sampai 12 April 2006 telah ditemukan 479 kasus kumulatif dan dicurigai flu burun...

  7. Non-Maxwellian electron distribution functions due to self-generated turbulence in collisionless guide-field reconnection

    CERN Document Server

    Muñoz, P A

    2016-01-01

    Non-Maxwellian electron velocity space distribution functions (EVDF) are useful signatures of plasma conditions and non-local consequences of collisionless magnetic reconnection. In the past, the evolution of the EVDFs was investigated mainly for antiparallel or weak-guide-field reconnection. The shape of EVDFs is, however, not well known yet for oblique (or component-) reconnection in dependence on a finite guide magnetic field component perpendicular to the reconnection plane. In view of the multi-spacecraft mission MMS, we derive the non-Maxwellian features of EVDFs formed by collisionless magnetic reconnection starting from very weak ($b_g\\approx0$) up to very strong ($b_g=8$) guide-field strengths $b_g$, taking into account the feedback of the self-generated turbulence. For this sake, we carry out 2.5D fully-kinetic Particle-in-Cell (PiC) simulations using the ACRONYM code. We obtained anisotropic EVDFs and the distribution of electron beams propagating along the separatrices as well as in the exhaust re...

  8. The effect of guide-field and boundary conditions on collisionless magnetic reconnection in a stressed X-point collapse

    CERN Document Server

    von der Pahlen, J Graf

    2014-01-01

    Works of D. Tsiklauri, T. Haruki, Phys. of Plasmas, 15, 102902 (2008) and D. Tsiklauri and T. Haruki, Phys. of Plasmas, 14, 112905, (2007) are extended by inclusion of the out-of-plane magnetic (guide) field. In particular, magnetic reconnection during collisionless, stressed $X$-point collapse for varying out-of-plane guide-fields is studied using a kinetic, 2.5D, fully electromagnetic, relativistic particle-in-cell numerical code. Cases for both open and closed boundary conditions are investigated, where magnetic flux and particles are lost and conserved respectively. It is found that reconnection rates and out-of-plane currents in the $X$-point increase more rapidly and peak sooner in the closed boundary case, but higher values are reached in the open boundary case. The normalized reconnection rate is fast: 0.10-0.25. In the open boundary case an increase of guide-field yields later onsets in the reconnection peak rates, while in the closed boundary case initial peak rates occur sooner but are suppressed. ...

  9. BIRD FLU (AVIAN INFLUENZA)

    OpenAIRE

    Ali ACAR; Bulent BESIRBELLIOÐLU

    2005-01-01

    Avian influenza (bird flu) is a contagious disease of animals caused by influenza A viruses. These flu viruses occur naturally among birds. Actually, humans are not infected by bird flu viruses.. However, during an outbreak of bird flu among poultry, there is a possible risk to people who have contact infect birds or surface that have been contaminated with excreations from infected birds. Symptoms of bird flu in humans have ranged from typical flu-like symptoms to eye infections, pneumonia, ...

  10. The avian haemophili.

    OpenAIRE

    Blackall, P. J.

    1989-01-01

    There are four currently recognized taxa to accommodate the avian haemophili: Haemophilus paragallinarum, Pasteurella avium, Pasteurella volantium, and Pasteurella species A (the last three being formerly united as Haemophilus avium). A range of other taxa has also been recognized, but they have been neither named nor assigned to a genus. All of these various taxa, legitimate and otherwise, have the common characteristic of requiring V factor, but not X factor, for in vitro growth. Several re...

  11. Avian psychology and communication.

    OpenAIRE

    Rowe, Candy; Skelhorn, John

    2004-01-01

    The evolution of animal communication is a complex issue and one that attracts much research and debate. 'Receiver psychology' has been highlighted as a potential selective force, and we review how avian psychological processes and biases can influence the evolution and design of signals as well as the progress that has been made in testing these ideas in behavioural studies. Interestingly, although birds are a focal group for experimental psychologists and behavioural ecologists alike, the i...

  12. Sensitivity and entanglement in the avian chemical compass

    Science.gov (United States)

    Zhang, Yiteng; Berman, Gennady P.; Kais, Sabre

    2014-10-01

    The radical pair mechanism can help to explain avian orientation and navigation. Some evidence indicates that the intensity of external magnetic fields plays an important role in avian navigation. In this paper, using a two-stage model, we demonstrate that birds could reasonably detect the directions of geomagnetic fields and gradients of these fields using a yield-based chemical compass that is sensitive enough for navigation. Also, we find that the lifetime of entanglement in this proposed compass is angle dependent and long enough to allow adequate electron transfer between molecules.

  13. Sensitivity and Entanglement in the Avian Chemical Compass

    CERN Document Server

    Zhang, Yiteng; Kais, Sabre

    2014-01-01

    The Radical Pair Mechanism can help to explain avian orientation and navigation. Some evidence indicates that the intensity of external magnetic fields plays an important role in avian navigation. In this paper, based on a two-stage strategy, we demonstrate that birds could reasonably detect the directions of geomagnetic fields and gradients of these fields using a yield-based chemical compass that is sensitive enough for navigation. Also, we find that the lifetime of entanglement in this proposed compass is angle-dependent and long enough to allow adequate electron transfer between molecules.

  14. Grid attacks avian flu

    CERN Multimedia

    2006-01-01

    During April, a collaboration of Asian and European laboratories analysed 300,000 possible drug components against the avian flu virus H5N1 using the EGEE Grid infrastructure. Schematic presentation of the avian flu virus.The distribution of the EGEE sites in the world on which the avian flu scan was performed. The goal was to find potential compounds that can inhibit the activities of an enzyme on the surface of the influenza virus, the so-called neuraminidase, subtype N1. Using the Grid to identify the most promising leads for biological tests could speed up the development process for drugs against the influenza virus. Co-ordinated by CERN and funded by the European Commission, the EGEE project (Enabling Grids for E-sciencE) aims to set up a worldwide grid infrastructure for science. The challenge of the in silico drug discovery application is to identify those molecules which can dock on the active sites of the virus in order to inhibit its action. To study the impact of small scale mutations on drug r...

  15. Experimental study of flow field in interference area between impeller and guide vane of axial flow pump

    Institute of Scientific and Technical Information of China (English)

    张华; 施卫东; 陈斌; 曹卫东; 张启华

    2014-01-01

    Axial flow pump is a kind of typical pumps with rotor-stator interaction, thus the measurement of the flow field between impeller and guide vane would facilitate the study of the internal rotor-stator interaction mechanism. Through a structural modifi-cation of a traditional axial flow pump, the requirements of particle image velocimetry (PIV) measurement are met. Under the condition of opt.0.8Q , the axial vortex is identified between impeller hub and guide vane hub, which is developed into the main flow and to affect the movement when the relative positions of impeller and guide vane at different flow rates are the same. Besides, the development and the dissipation of the tip leakage and the passage vortex in impeller passages are mainly responsible for the difference of the flow field close to the outer rim. As the flow rate decreases, the distribution of the meridional velocities at the impeller outlet becomes more non-uniform and the radial velocity component keeps increasing. The PIV measurement results under the condition of opt.1.0Q indicate that the flow separation and the trailing vortex at the trailing edge of a blade are likely to result in a velocity sudden change in this area, which would dramatically destroy the continuity of the flow field. Moreover, the radial direction of the flow between impeller and guide vane on the measurement plane does not always point from hub to rim. For a certain position, the direction is just from rim to hub, as is affected by the location of the intersection line of the shooting section and the impeller blade on the impeller as well as the angle between the intersection line and the rotating shaft.

  16. INVESTIGATION OF VISCOUS FLOW FIELD AROUND AN APPENDED REVOLUTION BODY WITH GUIDE VANE PROPELLER

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A RANS solver is presented to numerically simulate the viscous wake of an appended revolution body with guide vane propeller at the Reynolds number 107. The k-ε turbulence model together with wall function is used. The resulting finite difference equations are solved by SIMPLEC and ADI. The technique of rising up the bottom surface is presented to overcome radial contraction problem in Cartesian coordinate system. The three-dimensional body forces are separately adopted to model the affection of the guide vane and propeller. The detailed flow characteristics,especially the counter-swirl component generated by the guide vane in the propeller inflow, are numerically seized successfully. Compared with the experimental data, The computational axial velocity on the propeller disk plane comes up to engineering requirement.

  17. Field Testing Competency-Based Vocational Education Student Learning Guides Developed at Ridge Vocational-Technical Center. From August 1, 1981 to June 30, 1982. Final Report.

    Science.gov (United States)

    Andreyka, Robert E.

    This project's main objective was to field test competency-based vocational education (CBVE) student learning guides developed during 1979-1981 at Ridge Vocational-Technical Center (RVTC) (Florida). The learning guides were for six programs: clerical occupations, cosmetology, heavy duty truck/bus mechanics, industrial electricity, masonry, and…

  18. Avian influenza: Vaccination and control

    Science.gov (United States)

    Avian influenza (AI) is a viral disease of poultry that remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Strategies to control avian influenza (AI) virus are developed to prevent, manage or eradicate the virus from the country, re...

  19. Echolocation Reconsidered: Using Spatial Variations in the Ambient Sound Field To Guide Locomotion.

    Science.gov (United States)

    Ashmead, Daniel H.; Wall, Robert S.; Eaton, Susan B.; Ebinger, Kiara A.; Snook-Hill, Mary-Maureen; And Others

    1998-01-01

    Presents an acoustical model and evidence from four experiments that children with visual impairments use the buildup of low-frequency sound along walls to guide locomotion. The model differs from the concept of echolocation by emphasizing sound that is ambient, rather than self-produced, and of low frequency. (Author/CR)

  20. Concrete in the Field-II; Instructor's Guide; Pilot Program Edition.

    Science.gov (United States)

    Portland Cement Association, Cleveland, OH.

    This guide, prepared for a 2-year course in junior colleges and technical institutes, is designed to be a national program to train persons for employment as technicians in the cement and concrete industries. Included are 48 session outlines divided into six units of study. Each unit contains objectives, outline, related information, and…

  1. Field Guide to Northeastern Ferns. New York State Museum Bulletin Number 444.

    Science.gov (United States)

    Ogden, Eugene C.

    This guide was developed for use by individuals with little or no botanical training who wish to identify native ferns of New York, New England, New Jersey, and Pennsylvania. A random access key, developed by the author, provides multiple pathways for identification of 60 species in 29 genera of ferns. (CS)

  2. A field guide to the Silurian Echinodermata of the British Isles: Part 1 - Eleutherozoa and Rhombifera

    NARCIS (Netherlands)

    Lewis, D.N.; Donovan, S.K.; Crabb, P.; Gladwell, D.J.

    2007-01-01

    The Palaeozoic echinoderms of the British Isles are most diverse in the Silurian and Lower Carboniferous. This guide discusses and illustrates members of all major groups of echinoderms, apart from the crinoids, from the Silurian of these islands. Groups considered include the echinoids (five taxa),

  3. Strategies for Change: A Field Guide to Social Marketing for School Health Professionals

    Science.gov (United States)

    American School Health Association (NJ3), 2004

    2004-01-01

    Strategies for Change outlines how to use social marketing strategies to influence change in the health programs in a building, district or community. Authors describe how to develop a strategy to influence district administrators, school board members, colleagues and parents. This step-by-step guide leads through the process for developing,…

  4. Preparation of the narrow size distribution USPIO in mesoporous silica for magnetic field guided drug delivery and release

    Energy Technology Data Exchange (ETDEWEB)

    Zapotoczny, B., E-mail: bartlomiej.zapotoczny@o2.pl [Institute of Physics, University of Zielona Góra, ul. Szafrana 4a, 65-069 Zielona Góra (Poland); Guskos, N., E-mail: ngouskos@phys.uoa.gr [Department of Solid State Physics, University of Athens, Panepistimiopolis 15 784 (Greece); Institute of Physics, West Pomeranian University of Technology, Al. Piastów 17, 70-310 Szczecin (Poland); Kozioł, J.J., E-mail: j.koziol@wnb.uz.zgora.pl [Faculty of Biological Sciences, University of Zielona Góra, ul. Szafrana 1, 65-516 Zielona Góra (Poland); Dudek, M.R., E-mail: M.Dudek@if.uz.zgora.pl [Institute of Physics, University of Zielona Góra, ul. Szafrana 4a, 65-069 Zielona Góra (Poland)

    2015-01-15

    Ultra-small superparamagnetic iron oxides (USPIO) with an average diameter of 2 nm were synthesized in mesoporous silica using the method of co-precipitation of Fe{sup 2+} and Fe{sup 3+} ions in aqueous solution directly in the silica nanopores. Two types of the silica material, hexagonal phase MCM-41 and mesoporous silica spheres (MSS), were used. The resulting magnetically modified silica samples show high-quality superparamagnetic properties which persist also at low temperatures near 2 K. Their magnetization saturation in an applied external magnetic field exceeds 15 emu/g. The magnetically modified silica samples were studied with the help of the ferromagnetic resonance (FMR), SQUID-magnetometry, X-ray diffraction (XRD), dynamic light scattering (DLS) and TEM/EDX microscopy. The studies were complemented by confirming the possibility of drug release by the modified silica samples where the standard fluorescent dye was used as an example. The prepared material is suggested to be considered for magnetic field guided drug delivery and release. - Highlights: • Magnetically modified silica material for magnetic field guided drug delivery is suggested. • Ultra-small iron oxides (USPIO) in mesoporous silica MCM-41 and MSS are synthesized. • USPIO@MCM-41 and USPIO@MSS are superparamagnetic even in temperature of 2 K. • Their magnetization saturation in an applied external magnetic field exceeds 15 emu/g. • The average size of the synthesized USPIO is 2 nm.

  5. INFX GUIDE: DEPARTMENT OF ENERGY BILATERAL AGREEMENTS FOR COOPERATION IN THE FIELD OF RADIOACTIVE WASTE MANAGEMENT (INFX: INTERNATIONAL INFORMATION EXCHANGE)

    Energy Technology Data Exchange (ETDEWEB)

    Harman, K. M.; Lakey, L. T.; Leigh, I. W.; Jeffs, A. G.

    1985-07-01

    As the U. S. Department of Energy (DOE) and DOE contractors have increased the magnitude and scope of their cooperative activities with other nations in the nuclear fuel cycle and waste management field, a need has developed for ready sources of information concerning foreign waste management programs, DOE technology exchange policies, bilateral fuel cycle and waste management agreements and plans and activities to implement those agreements. The INFX (International InLormation E~change) Guide is one of a series of documents that have been prepared to provide that information. The INFX Guide has been compiled under the charter of PNL's International Support Office (IPSO) to maintain for DOE a center to collect, organize, evaluate and disseminate information on foreign and international radioactive waste management programs. Because the information in this document is constantly subject to change, the document is assembled in loose-leaf form to accommodate frequent updates.

  6. A Guided Mode View on Near-Field Scanning Optical Microscopy Measurements of Optical Magnetic Fields with Slit Probes

    OpenAIRE

    Stoffer, Remco; Hammer, Manfred; Ivanova, O. V.; Hoekstra, Hugo J.W.M.

    2010-01-01

    Recent Near-field Scanning Optical Microscopy (NSOM) experiments with slit metal coated probes claim to measure the out-of-plane optical magnetic field around a dielectric sample waveguide [1]. The observations can also be explained by mode overlap calculations.

  7. 1978 Insect Pest Management Guide: Field and Forage Crops. Circular 899.

    Science.gov (United States)

    Illinois Univ., Urbana. Cooperative Extension Service.

    This circular lists suggested uses of insecticides for the control of field crop pests. Suggestions are given for selection, dosage and application of insecticides to control pests in field corn, alfalfa and clover, small grains, soybeans and grain sorghum. (CS)

  8. Field Hockey-Lacrosse Guide with Official Rules. June 1972 - June 1974.

    Science.gov (United States)

    Thornburg, Mary Lou, Ed.; Pitts, Jackie, Ed.

    Rules for women's field hockey and lacrosse from June 1972 to June 1974 are discussed. Standards in sports for girls and women are detailed as is the Division for Girls and Women's Sports (DGWS) statement of beliefs. Specific articles on field hockey techniques, skills, services available through the United States Field Hockey Association, rules,…

  9. Antigenic characterization of avian influenza H9 subtype isolated from desi and zoo birds

    Directory of Open Access Journals (Sweden)

    Farrukh Saleem

    2011-08-01

    Full Text Available Avian influenza is a viral infection which affects mainly the respiratory system of birds. The H9N2 considered as low pathogenic avian influenza (LPAI virus and continuously circulating in poultry flocks causing enormous economic losses to poultry industry of Pakistan. As these viruses have RNA genome and their RNA polymerase enzyme lacks proof reading activity which resulted in spontaneous mutation in surface glycoproteins (HA and NA and reassortment of their genomic segments results in escape from host immune response produced by the vaccine. Efforts made for the isolation and identification of avian influenza virus from live desi and zoo birds of Lahore and performed antigenic characterization. The local vaccines although gives a little bit less titer when we raise the antisera against these vaccines but their antisera have more interaction with the local H9 subtype antigen so it gives better protective immune response. Infected chicken antisera are more reactive as compare to rabbit antisera. This shows that our isolates have highest similarity with the currently circulating viruses. These results guided us to devise a new control strategy against avian influenza viral infections. The antigenic characterization of these avian influenza isolates helped us to see the antigenic differences between the isolates of this study and H9 subtype avian influenza viruses used in vaccines. Therefore, this study clearly suggests that a new local H9 subtype avian influenza virus should be used as vaccinal candidate every year for the effective control of influenza viral infections of poultry.

  10. Avian Influenza Infection Dynamics in Minor Avian Species

    OpenAIRE

    Bertran Dols, Kateri

    2013-01-01

    Avian influenza (AI) has become one of the most important challenges that ever emerged from animal reservoirs. The constant outbreaks detected worldwide in domestic and wild bird species are of concern to the economics of the poultry industry, wildlife conservation, and animal and public health. Susceptibility to AI viruses (AIVs) varies deeply among avian species, as well as their possible role as sentinels, intermediate hosts or reservoirs. To date, several experimental studies and natural ...

  11. Analysis of the dependence of the guided mode field distribution on the silica bridges in hollow-core Bragg fibers

    DEFF Research Database (Denmark)

    Selleri, S.; Poli, F.; Foroni, M.;

    2007-01-01

    The guiding properties of fabricated air-silica Bragg fibers with different geometric characteristics have been numerically investigated through a modal solver based on the finite element method. The method has been used to compute the dispersion curves, the loss spectra and the field distribution...... of the modes sustained by the Bragg fibers under investigation. In particular, the silica bridge influence on the fundamental mode has been analyzed, by considering structures with different cross sections, that is an ideal Bragg fiber, without the silica nonosupports, a squared air-hole one and...... responsible of the loss peaks in the fiber transmission spectra, also experimentally measured. Surface modes are mainly localized in the regions of the cladding where the bridge supports join the cladding rings, forming silica islands where the field can focuses....

  12. Field and laboratory guide to freshwater cyanobacteria harmful algal blooms for Native American and Alaska Native communities

    Science.gov (United States)

    Rosen, Barry H.; Ann St. Amand

    2015-01-01

    Cyanobacteria can produce toxins and form harmful algal blooms. The Native American and Alaska Native communities that are dependent on subsistence fishing have an increased risk of exposure to these cyanotoxins. It is important to recognize the presence of an algal bloom in a waterbody and to distinguish a potentially toxic harmful algal bloom from a non-toxic bloom. This guide provides field images that show cyanobacteria blooms, some of which can be toxin producers, as well as other non-toxic algae blooms and floating plants that might be confused with algae. After recognition of a potential toxin-producing cyanobacterial bloom in the field, the type(s) of cyanobacteria present needs to be identified. Species identification, which requires microscopic examination, may help distinguish a toxin-producer from a non-toxin producer. This guide also provides microscopic images of the common cyanobacteria that are known to produce toxins, as well as images of algae that form blooms but do not produce toxins.

  13. On reduction of transient process duration in a relativistic Cherenkov microwave oscillator without a guiding magnetic field

    Science.gov (United States)

    Tot'meninov, E. M.; Klimov, A. I.

    2016-06-01

    Coupling impedance Z 0 of a continuous relativistic electron beam with the fundamental harmonic of the TM01 wave slowed down to the speed of light in a slow-wave structure (SWS) based on a hollow corrugated waveguide is estimated analytically and using the program based on the scattering matrix method. It is shown that Z 0 in relativistic Cherenkov microwave oscillators without a guiding magnetic field realized in earlier experiments with the given type of interaction amounts to about 6-7 Ω, which is several times higher than the coupled impedances averaged over the SWS cross section for-1 and +1 spatial harmonics of the operating wave and can be increased in future to values exceeding 10 Ω due to a decrease in the average SWS diameter in admissible limits. In numerical simulation using the KARAT code, the possibility of reduction of the time of stabilization of oscillations of the Cherenkov microwave oscillator without a guiding magnetic field by 1.5 times is demonstrated.

  14. Influenza pandemics and avian flu

    OpenAIRE

    2005-01-01

    Douglas Fleming is general practitioner in a large suburban practice in Birmingham. In this article he seeks to clarify clinical issues relating to potential pandemics of influenza, including avian influenza

  15. Field Guide to Rock Weathering. Earth Science Curriculum Project Pamphlet Series PS-1.

    Science.gov (United States)

    Boyer, Robert E.

    Highlighted are the effects of weathering through field investigations of the environment, both natural rocks, and the urban environment's pavements, buildings, and cemeteries. Both physical weathering and chemical weathering are discussed. Questions are presented for post-field trip discussion. References and a glossary are provided. (Author/RE)

  16. The Avian Development Facility

    Science.gov (United States)

    2003-01-01

    The Avian Development Facility (ADF) supports 36 eggs in two carousels, one of which rotates to provide a 1-g control for comparing to eggs grown in microgravity. The ADF was designed to incubate up to 36 Japanese quail eggs, 18 in microgravity and 18 in artificial gravity. The two sets of eggs were exposed to otherwise identical conditions, the first time this is been accomplished in space. Eggs are preserved at intervals to provide snapshots of their development for later analysis. Quails incubate in just 15 days, so they are an ideal species to be studied within the duration of space shuttle missions. Further, several investigators can use the same specimens to address different questions. The ADF originated in NASA's Shuttle Student Involvement program in the 1980s and was developed under the NASA Small Business Irnovation Research program. In late 2001, the ADF made its first flight and carried eggs used in two investigations.

  17. BIRD FLU (AVIAN INFLUENZA

    Directory of Open Access Journals (Sweden)

    Ali ACAR

    2005-12-01

    Full Text Available Avian influenza (bird flu is a contagious disease of animals caused by influenza A viruses. These flu viruses occur naturally among birds. Actually, humans are not infected by bird flu viruses.. However, during an outbreak of bird flu among poultry, there is a possible risk to people who have contact infect birds or surface that have been contaminated with excreations from infected birds. Symptoms of bird flu in humans have ranged from typical flu-like symptoms to eye infections, pneumonia, severe respiratory diseases and other severe and life-threatening complications. In such situation, people should avoid contact with infected birds or contaminated surface, and should be careful when handling and cooking poultry. [TAF Prev Med Bull 2005; 4(6.000: 345-353

  18. Low Speed Avian Maneuvering Flight

    OpenAIRE

    Ros, Ivo

    2013-01-01

    Low speed avian maneuvering flight is an ecologically crucial behavior that has contributed to the explosive diversification of several avian taxa by allowing access to complex spatial environments. Negotiating a sharp aerial turn requires finely tuned interactions between an animal's sensory-motor system and its environment. My thesis work focuses on how aerodynamic forces, wing and body dynamics, and sensory feedback interact during aerial turning in the pigeon (Columba livea).

  19. Avian influenza : a review article

    OpenAIRE

    A. Yalda; EMADI H; M. Haji Abdolbaghi

    2006-01-01

    The purpose of this paper is to provides general information about avian influenza (bird flu) and specific information about one type of bird flu, called avian influenza A (H5N1), that has caused infections in birds in Asia and Europe and in human in Asia. The main materials in this report are based on the World Health Organization (WHO) , world organization for animal health (OIE) , food and agriculture organization of the united nations (FAO) information and recommendations and review of th...

  20. Measurement and Definitions of Obesity In Childhood and Adolescence: A field guide for the uninitiated

    Directory of Open Access Journals (Sweden)

    Sweeting Helen N

    2007-10-01

    Full Text Available Abstract This paper aims to guide readers embarking on the complex literature in respect of childhood and adolescent obesity. It opens with a discussion of definitions of 'obesity' based on overall fat levels and the significance of fat distribution. This is followed by simple descriptions of the various techniques used to measure fat, including density-based, scanning, bioelectrical impedance and anthropometric methods. The paper then turns to 'overweight' and the measurement of weight in relation to height, particularly via body mass index (BMI. While it is a relatively simple measure and a valuable tool, BMI has several disadvantages, which are described. These include a lack of consensus on which values should be used to define 'overweight' or 'obese', with the result that the literature contains a confusing multiplicity of child and adolescent obesity rates.

  1. Thromboelastography in Selected Avian Species.

    Science.gov (United States)

    Strindberg, Sophie; Nielsen, Tenna W; Ribeiro, Ângela M; Wiinberg, Bo; Kristensen, Annemarie T; Bertelsen, Mads F

    2015-12-01

    Currently available assay methods and reagents are not optimized for evaluating avian hemostasis; therefore, assessing avian coagulopathies is challenging. Recently, thromboelastography (TEG), which measures the viscoelastic properties of blood, has been used clinically in mammalian species to diagnose and characterize hemostatic disorders. To evaluate TEG in healthy individuals of 6 avian species, we modified existing mammalian TEG protocols to allow analysis of citrated, avian whole-blood samples collected from scarlet ibis (Eudocimus ruber) (n = 13), American flamingos ( Phoenicopterus ruber ) (n = 13), helmeted Guinea fowl ( Numida meleagris ) (n = 12), Amazon parrots (Amazona species) (n = 9), Humboldt penguins ( Spheniscus humboldti ) (n = 6), and domestic chickens (n = 16). Activated partial thromboplastin time, prothrombin time, and fibrinogen were measured as a means of comparison. Regardless of the mode of activation, clot formation in the species studied was markedly delayed compared with mammals. Because of prolonged reaction time (14.7-52.7 minutes) with kaolin and diluted tissue factor, undiluted human tissue factor was used in all avian samples because it provided the shortest reaction time. Species differed significantly in reaction time (P = .007), clotting rate (P < .001), rate of clot formation (α angle; P < .001), and maximum amplitude (P < .001) values, indicating that species-specific reference intervals are necessary. Based on these results, TEG with specific reference intervals could prove useful in evaluating avian hemostatic disorders. PMID:26771317

  2. Toward real-time endoscopically-guided robotic navigation based on a 3D virtual surgical field model

    Science.gov (United States)

    Gong, Yuanzheng; Hu, Danying; Hannaford, Blake; Seibel, Eric J.

    2015-03-01

    The challenge is to accurately guide the surgical tool within the three-dimensional (3D) surgical field for roboticallyassisted operations such as tumor margin removal from a debulked brain tumor cavity. The proposed technique is 3D image-guided surgical navigation based on matching intraoperative video frames to a 3D virtual model of the surgical field. A small laser-scanning endoscopic camera was attached to a mock minimally-invasive surgical tool that was manipulated toward a region of interest (residual tumor) within a phantom of a debulked brain tumor. Video frames from the endoscope provided features that were matched to the 3D virtual model, which were reconstructed earlier by raster scanning over the surgical field. Camera pose (position and orientation) is recovered by implementing a constrained bundle adjustment algorithm. Navigational error during the approach to fluorescence target (residual tumor) is determined by comparing the calculated camera pose to the measured camera pose using a micro-positioning stage. From these preliminary results, computation efficiency of the algorithm in MATLAB code is near real-time (2.5 sec for each estimation of pose), which can be improved by implementation in C++. Error analysis produced 3-mm distance error and 2.5 degree of orientation error on average. The sources of these errors come from 1) inaccuracy of the 3D virtual model, generated on a calibrated RAVEN robotic platform with stereo tracking; 2) inaccuracy of endoscope intrinsic parameters, such as focal length; and 3) any endoscopic image distortion from scanning irregularities. This work demonstrates feasibility of micro-camera 3D guidance of a robotic surgical tool.

  3. Variational Symplectic Integrator for Long-Time Simulations of the Guiding-Center Motion of Charged Particles in General Magnetic Fields

    Energy Technology Data Exchange (ETDEWEB)

    H. Qin and X. Guan

    2008-02-11

    A variational symplectic integrator for the guiding-center motion of charged particles in general magnetic fields is developed for long-time simulation studies of magnetized plasmas. Instead of discretizing the differential equations of the guiding-center motion, the action of the guiding-center motion is discretized and minimized to obtain the iteration rules for advancing the dynamics. The variational symplectic integrator conserves exactly a discrete Lagrangian symplectic structure, and has better numerical properties over long integration time, compared with standard integrators, such as the standard and variable time-step fourth order Runge-Kutta methods.

  4. Variational Symplectic Integrator for Long-Time Simulations of the Guiding-Center Motion of Charged Particles in General Magnetic Fields

    International Nuclear Information System (INIS)

    A variational symplectic integrator for the guiding-center motion of charged particles in general magnetic fields is developed for long-time simulation studies of magnetized plasmas. Instead of discretizing the differential equations of the guiding-center motion, the action of the guiding-center motion is discretized and minimized to obtain the iteration rules for advancing the dynamics. The variational symplectic integrator conserves exactly a discrete Lagrangian symplectic structure, and has better numerical properties over long integration time, compared with standard integrators, such as the standard and variable time-step fourth order Runge-Kutta methods.

  5. Conceptual design and sample preparation of electrode covered single glass macro-capillaries for studying the effect of an external electric field on particle guiding

    Energy Technology Data Exchange (ETDEWEB)

    Wartak, A. [Institute of Applied Physics, TU Wien, A-1040 Vienna (Austria); Bereczky, R.J., E-mail: bereczky.reka@atomki.mta.hu [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), H-4026 Debrecen, P.O. Box 51 (Hungary); Kowarik, G. [Institute of Applied Physics, TU Wien, A-1040 Vienna (Austria); Tőkési, K. [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), H-4026 Debrecen, P.O. Box 51 (Hungary); Aumayr, F. [Institute of Applied Physics, TU Wien, A-1040 Vienna (Austria)

    2015-07-01

    We present the design and construction of a macroscopic glass capillary covered by electrodes on the outside. With these new capillary targets it will be possible to study the influence of an external electric field on the process of guiding of charged particles through a capillary. The new degrees of freedoms will contribute to both a better fundamental understanding of the guiding phenomenon but might also be of use in practical applications.

  6. Enhancing isolation of antenna arrays by simultaneously blocking and guiding magnetic field lines using magnetic metamaterials

    Science.gov (United States)

    Liu, Zhaotang; Wang, Jiafu; Qu, Shaobo; Zhang, Jieqiu; Ma, Hua; Xu, Zhuo; Zhang, Anxue

    2016-10-01

    In this article, we propose to enhance the isolation of antenna arrays by manipulating the near-field magnetic coupling between adjacent antennas using magnetic metamaterials (MMs). Due to the artificially designed negative or large permeability, MMs can concentrate or block the magnetic field lines where they are located, which allows us to tune the near-field magnetic coupling strengths between antennas. MMs can play a two-fold role in enhancing antenna isolation. On one hand, the magnetic fields can be blocked in gaps between adjacent antennas using MMs with negative permeability; on the other hand, the magnetic fields can be pulled towards the borders of the antenna array using MMs with large permeability. As an example, we demonstrated a four-element patch antenna array with split-ring resonators (SRR) integrated in the substrate. The measured results show that the isolation can be enhanced by more than 10 dB with the integration of SRRs, even if the gap between antennas is only about 0.082λ. This work provides an effective alternative to the design of high-isolation antenna arrays.

  7. Acid Rain: A Resource Guide for Classroom, Laboratory, Field, and Debate Topics.

    Science.gov (United States)

    Stoss, Frederick W.

    1987-01-01

    Provides a partially annotated bibliography of journals and book chapters which deal with acid rain. Includes selections which provide background information, ideas for introducing acid rain into science or social studies curricula, inventories of audio-visual aids, and non-print media to supplement classroom, laboratory, and field instruction.…

  8. Religious Studies: The Shaping of a Field and a Guide to Reference Resources.

    Science.gov (United States)

    Lippy, Charles H.

    1992-01-01

    Discusses the development of religious studies as an academic discipline. Examines the work of leading thinkers in the field, including anthropologists Sir James Fraser and Edward Burnett Taylor, sociologist Max Weber, and psychologist Erik Erikson. Identifies some of the many reference works that deal with religious studies. (SG)

  9. A Guide to Field Studies for the Coastal Environment. Project CAPE Teaching Module.

    Science.gov (United States)

    Barker, Wells J.

    Twenty-five coastal field study investigations, comprising this supplement to a junior high school earth science curriculum, are designed to help students obtain a fuller understanding of: (1) their coastal environment, (2) some of the problems which confront it, (3) the interrelationships between the land and the surrounding bodies of water, and…

  10. SU-E-P-14: Dosimetric Effects of Magnetic Field in MRI-Guided Radiation Therapy Delivery for Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G; Currey, A; Li, X [Medical College of Wisconsin, Milwaukee, WI (United States)

    2015-06-15

    Purpose: MRI-guided radiation therapy (RT) delivery would be beneficial for breast irradiation. The electron return effect due to the presence of a transverse magnetic field (TMF) may cause dosimetric issues on dose on skin and at the lung-tissue interface. The purpose of this study is to investigate these issues. Methods: IMRT plans with tangential beams and VMAT plans with 200 degree arcs to cover ipsilateral breast were generated for 10 randomly selected breast cancer cases using a research planning system (Monaco, Elekta) utilizing Monte Carlo dose calculation with or without a TMF of 1.5 T. Plans were optimized to deliver uniform dose to the whole breast with an exclusion of 5 mm tissue under the skin (PTV-EVAL). All four plans for each patient were re-scaled to have the same PTV-EVAL volume to receive the same prescription dose. The skin is defined as the first 5 mm of ipsilateral-breast tissue, plus extensions in the surrounding region. Results: The presence of 1.5 T TMF resulted in (1)increased skin dose, with the mean and maximum skin dose increase of 5% and 9%, respectively; (2) similar dose homogeneity within the PTV-EVAL; (3) the slightly improved (3%) dose homogeneity in the whole breast; (4) Averages of 9 and 16% increases in V5 and V20, respectively, for ipsilateral lung; and (5) increased the mean heart dose by 34%. VMAT plans don’t improve whole breast dose uniformity as compared that to the tangential plans. Conclusion: The presence of transverse magnetic field in MRI-guided RT delivery for whole breast irradiation can Result in slightly improved dose homogeneity in the whole breast, increased dose to the ipsilateral lung, heart, and skin. Plan optimization with additional specific dose volume constraints may eliminate/reduce these dose increases. This work is partially supported by Elekta Inc.

  11. Quantum Zeno Effect Underpinning the Radical-Ion-Pair Mechanism of Avian Magnetoreception

    CERN Document Server

    Kominis, I K

    2008-01-01

    The intricate biochemical processes underlying avian magnetoreception, the sensory ability of migratory birds to navigate using earths magnetic field, have been narrowed down to spin-dependent recombination of radical-ion pairs to be found in avian species retinal proteins. The avian magnetic field detection is governed by the interplay between magnetic interactions of the radicals unpaired electrons and the radicals recombination dynamics. Critical to this mechanism is the long lifetime of the radical-pair spin coherence, so that the weak geomagnetic field will have a chance to signal its presence. It is here shown that a fundamental quantum phenomenon, the quantum Zeno effect, is at the basis of the radical-ion-pair magnetoreception mechanism. The quantum Zeno effect naturally leads to long spin coherence lifetimes, without any constraints on the systems physical parameters, ensuring the robustness of this sensory mechanism. Basic experimental observations regarding avian magnetic sensitivity are seamlessly...

  12. Avian mycoplasmosis update

    Directory of Open Access Journals (Sweden)

    ER Nascimento

    2005-03-01

    Full Text Available Avian mycoplasmas occur in a variety of bird species. The most important mycoplasmas for chickens and turkeys are Mycoplasma gallisepticum (MG, M. synoviae (MS, and M. meleagridis. Besides, M. iowe (MI is an emerging pathogen in turkeys, but of little concern for chickens. Mycoplasmas are bacteria that lack cell wall and belong to the class Mollicutes. Although they have been considered extracellular agents, scientists admit nowadays that some of them are obligatory intracellular microorganisms, whereas all other mycoplasmas are considered facultative intracellular organisms. Their pathogenic mechanism for disease include adherence to host target cells, mediation of apoptosis, innocent bystander damage to host cell due to intimate membrane contact, molecular (antigen mimicry that may lead to tolerance, and mitotic effect for B and/or T lymphocytes, which could lead to suppressed T-cell function and/or production of cytotoxic T cell, besides mycoplasma by-products, such as hydrogen peroxide and superoxide radicals. Moreover, mycoplasma ability to stimulate macrophages, monocytes, T-helper cells and NK cells, results in the production of substances, such as tumor necrosing factor (TNF-alpha, interleukin (IL-1, 2, 6 and interferon (a, b, g. The major clinical signs seen in avian mycoplasmosis are coughing, sneezing, snicks, respiratory rales, ocular and nasal discharge, decreased feed intake and egg production, increased mortality, poor hatchability, and, primarily in turkeys, swelling of the infraorbital sinus(es. Nevertheless, chronic and unapparent infections are most common and more threatening. Mycoplasmas are transmitted horizontally, from bird to bird, and vertically, from dam to offspring through the eggs. Losses attributed to mycoplasmosis, mainly MG and MS infections, result from decreased egg production and egg quality, poor hatchability (high rate of embryonic mortality and culling of day-old birds, poor feed efficiency, increase in

  13. Field guide to research on seven roles of women: focussed biographies.

    OpenAIRE

    Oppong C; Church K

    1981-01-01

    ILO pub-wep pub. Working paper presenting a classification scheme for the social roles of women, intended to assist field workers in data collecting and data analysis relevant to the understanding of a range of demographic aspects and employment issues - suggests a framework of role behaviour (incl. Homemaker, parent, occupation, kinship and community role, etc.), And considers role strain, mental stress, expectations and conflict. Bibliography p. 52..

  14. An overview on avian influenza

    Directory of Open Access Journals (Sweden)

    Nelson Rodrigo da Silva Martins

    2012-06-01

    Full Text Available Avian influenza (AI is considered an exotic disease in the Brazilian poultry industry, according to the National Avian Health Program (PNSA, with permanent monitoring of domestic, exotic and native avian species. Brazil presents privileged environmental conditions of reduced risk. In addition, all commercial poultry and conservation holdings are registered in state or national inventories and geographically located (GPS for health control. Poultry health standards are adopted for the conformity to the international market, mostly for the intensified poultry destined for exportation, but also for companion exotic and native conservation facilities. Guidelines for monitoring and the diagnosis of AI are published by the PNSA and follow the standards proposed by the international health code (World Organization for Animal Health, Organization International des Epizooties - OIE and insure the free of status for avian influenza virus (AIV of LPAIV-low pathogenicity AIV and HPAIV-high pathogenicity AIV. In addition, the infections by mesogenic and velogenic Newcastle disease virus, Mycoplasma gallisepticum, M. synoviae and M. meleagridis, Salmonella enteric subspecies enterica serovar Gallinarum biovars Gallinarum and Pullorum are eradicated from reproduction. Controlled infections by S.enterica subspecies enterica serovars Enteritidis and Typhimurium are monitored for breeders. The vaccination of chickens in ovo or at hatch against Marek's disease is mandatory. Broiler production is an indoor activity, confinement which insures biosecurity, with safe distances from the potential AIV reservoir avian species. Worldwide HPAIV H5N1 notifications to the OIE, in March 2011, included 51 countries.

  15. The Avian Proghrelin System

    Directory of Open Access Journals (Sweden)

    Mark P. Richards

    2010-01-01

    Full Text Available To understand how the proghrelin system functions in regulating growth hormone release and food intake as well as defining its pleiotropic roles in such diverse physiological processes as energy homeostasis, gastrointestinal tract function and reproduction require detailed knowledge of the structure and function of the components that comprise this system. These include the preproghrelin gene that encodes the proghrelin precursor protein from which two peptide hormones, ghrelin and obestatin, are derived and the cognate receptors that bind proghrelin-derived peptides to mediate their physiological actions in different tissues. Also key to the functioning of this system is the posttranslational processing of the proghrelin precursor protein and the individual peptides derived from it. While this system has been intensively studied in a variety of animal species and humans over the last decade, there has been considerably less investigation of the avian proghrelin system which exhibits some unique differences compared to mammals. This review summarizes what is currently known about the proghrelin system in birds and offers new insights into the nature and function of this important endocrine system. Such information facilitates cross-species comparisons and contributes to our understanding of the evolution of the proghrelin system.

  16. Avian infectious laryngotracheitis.

    Science.gov (United States)

    Bagust, T J; Jones, R C; Guy, J S

    2000-08-01

    Avian infectious laryngotracheitis (ILT) herpesvirus continues to cause sporadic cases of respiratory disease in chickens world-wide. Sources of transmission of ILT infection are three-fold, namely: chickens with acute upper respiratory tract disease, latently infected 'carrier' fowls which excrete infectious laryngotracheitis virus (ILTV) when stressed, and all fomites (inanimate articles as well as the personnel in contact with infected chickens). Infectious laryngotracheitis virus infectivity can persist for weeks to months in tracheal mucus or carcasses. Rigorous site biosecurity is therefore critical in ILT disease control. Furthermore, while current (modified live) ILT vaccines can offer good protection, the strains of ILTV used in vaccines can also produce latent infections, as well as ILT disease following bird-to-bird spread. The regional nature of reservoirs of ILTV-infected flocks will tend to interact unfavourably with widely varying ILT control practices in the poultry industry, so as to periodically result in sporadic and unexpected outbreaks of ILT in intensive poultry industry populations. Precautions for trade-related movements of chickens of all ages must therefore include an accurate knowledge of the ILT infection status, both of the donor and recipient flocks. PMID:10935275

  17. Radon as a guide to geothermal exploration. The case of Chipilapa geothermal field in El Salvador

    International Nuclear Information System (INIS)

    During the months September 1990 until January 1991 was realized in Chipilapa Geothermal field a Radon study utilizing nitrocelullose films as detector. The concentration of average Radon obtained was 125 pCi/l with a standard deviation of 51. As natural background of Radon concentration in the study area was establish a value of 50 pCi/l so it permitted to determine as an anomaly those ones concentrations upper than 100 pCi/l. The obtained results show interest zone the central and southwest of Chipilapa area, so also at east of Cuyanausul fault and along Agua Shuca fault. (Author)

  18. Diversity and Distribution of Avian Fauna of Swat, Khyber Pakhtunkhwa, Pakistan

    OpenAIRE

    Amir Jan Pathan; Shahroz Khan; Naveed Akhtar; Kausar Saeed

    2014-01-01

    This survey was conducted from January 2013 to December 2013 to explore the avian fauna of Swat valley and to find out the major threats to the avian fauna of the area as it was neglected for years. Direct and indirect methods were used in the study by visiting the field and by interviewing the local peoples and hunters about the current and past status of the avian fauna of the area. During the current study direct and indirect methods were used. A total of 138 species were recorded belongin...

  19. Guide to Mining Law and other important legal fields for training, further education and practice. 7. rev. ed.

    International Nuclear Information System (INIS)

    The focus of the latest edition is on the Federal Act on Mining which came into force on January 1st, 1982. The publication of the guide to mining law has been scheduled for this very moment, thus presenting the opportunity to obtain a general view of the new law. The text of the Federal Act on Mining, given in the annex, will make this task easier. The 7th edition, too, gives a description of other legal fields which are important to the mining industry, including relevant legal texts. The laws governing labour, social affairs and the environment are treated. Until recently neither a comprehensive description of environmental law from the viewpoint of the mining industry was available, nor a compilation of relevant excerpts. An overview of constitutional law and administrative law is the first in line in order to facilitate the user's approach to all other legal fields. Six graphical representations serve the better understanding of relationships in law. (orig./HP)

  20. Quantum Field Theory as a Problem of Resummation (Short guide to using summability methods)

    CERN Document Server

    Moroz, A V

    1992-01-01

    Thesis includes review on the large order behaviour of perturbation theory in quantum mechanical and field theory models; generalization of the Borel summability and strong asymptotic conditions to various (including horn-shaped) regions; discussion of analytic aspects of perturbation theory; examples which demonstrate differences between the Borel summability and generalized one; application to the Rayleigh-Schr\\"{o}dinger perturbation theory and to the definition of the operator valued functions. The new summability methods converges in the whole Mittag-Leffeler star of an analytical function and as such is useful for localization of singularities in the complex plane. Their position can be calculated even analytically provided large order behaviour of the Taylor series is known. Method can be implemented numerically as well.

  1. Trapping atoms in the evanescent field of laser written wave guides

    CERN Document Server

    Jukic, Dario; Walther, P; Szameit, A; Pohl, T; Götte, J B

    2016-01-01

    We analyze evanescent fields of laser written waveguides and show that they can be used to trap atoms close to the surface of an integrated optical atom chip. In contrast to subwavelength nanofibres it is generally not possible to create a stable trapping potential using only the fundamental modes. This is why we create a stable trapping potential by using two different laser colors, such that the waveguide supports two modes for the blue detuned laser, while for the red detuned light the waveguide has only a single mode. In particular, we study such a two-color trap for Cesium atoms, and calculate both the potential and losses for the set of parameters that are within experimental reach. We also optimize system parameters in order to minimize trap losses due to photon scattering and tunneling to the surface.

  2. Neuroethics 1995–2012. A Bibliometric Analysis of the Guiding Themes of an Emerging Research Field

    Science.gov (United States)

    Leefmann, Jon; Levallois, Clement; Hildt, Elisabeth

    2016-01-01

    In bioethics, the first decade of the twenty-first century was characterized by the emergence of interest in the ethical, legal, and social aspects of neuroscience research. At the same time an ongoing extension of the topics and phenomena addressed by neuroscientists was observed alongside its rise as one of the leading disciplines in the biomedical science. One of these phenomena addressed by neuroscientists and moral psychologists was the neural processes involved in moral decision-making. Today both strands of research are often addressed under the label of neuroethics. To understand this development we recalled literature from 1995 to 2012 stored in the Mainz Neuroethics Database (i) to investigate the quantitative development of scientific publications in neuroethics; (ii) to explore changes in the topics of neuroethics research within the defined time interval; (iii) to illustrate the interdependence of different research topics within the neuroethics literature; (iv) to show the development of the distribution of neuroethics research on peer-reviewed journals; and (v) to display the academic background and affiliations of neuroethics researchers. Our analysis exposes that there has been a demonstrative increase of neuroethics research while the issues addressed under this label had mostly been present before the establishment of the field. We show that the research on the ethical, legal and social aspects of neuroscience research is hardly related to neuroscience research on moral decision-making and that the academic backgrounds and affiliations of many neuroethics researchers speak for a very close entanglement of neuroscience and neuroethics. As our article suggests that after more than one decade there still is no dominant agenda for the future of neuroethics research, it calls for more reflection about the theoretical underpinnings and prospects to establish neuroethics as a marked-off research field distinct from neuroscience and the diverse branches

  3. Avian Influenza infection in Human

    OpenAIRE

    Mohan M; Trevor Francis Fernandez and Feroz Mohammed.M.S.

    2008-01-01

    Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds.All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe dise...

  4. The Radical Pair Mechanism and the Avian Chemical Compass: Quantum Coherence and Entanglement

    CERN Document Server

    Zhang, Yiteng; Kais, Sabre

    2015-01-01

    We review the spin radical pair mechanism which is a promising explanation of avian navigation. This mechanism is based on the dependence of product yields on (1) the hyperfine interaction involving electron spins and neighboring nuclear spins and (2) the intensity and orientation of the geomagnetic field. One surprising result is that even at ambient conditions quantum entanglement of electron spins can play an important role in avian magnetoreception. This review describes the general scheme of chemical reactions involving radical pairs generated from singlet and triplet precursors; the spin dynamics of the radical pairs; and the magnetic field dependence of product yields caused by the radical pair mechanism. The main part of the review includes a description of the chemical compass in birds. We review: the general properties of the avian compass; the basic scheme of the radical pair mechanism; the reaction kinetics in cryptochrome; quantum coherence and entanglement in the avian compass; and the effects o...

  5. Avian reproductive physiology

    Science.gov (United States)

    Gee, G.F.; Gibbons, Edward F.; Durrant, Barbara S.; Demarest, Jack

    1995-01-01

    Knowledge of the many physiological factors associated with egg production , fertility, incubation, and brooding in nondomestic birds is limited. Science knows even less about reproduction in most of the 238 endangered or threatened birds. This discussion uses studies of nondomestic and, when necessary, domestic birds to describe physiological control of reproduction. Studies of the few nondomestic avian species show large variation in physiological control of reproduction. Aviculturists, in order to successfully propagate an endangered bird, must understand the bird's reproductive peculiarities. First, investigators can do studies with carefully chosen surrogate species, but eventually they need to confirm the results in the target endangered bird. Studies of reproduction in nondomestic birds increased in the last decade. Still, scientists need to do more comparative studies to understand the mechanisms that control reproduction in birds. New technologies are making it possible to study reproductive physiology of nondomestic species in less limiting ways. These technologies include telemetry to collect information without inducing stress on captives (Howey et al., 1987; Klugman, 1987), new tests for most of the humoral factors associated with reproduction, and the skill to collect small samples and manipulate birds without disrupting the physiological mechanisms (Bercovitz et al., 1985). Managers are using knowledge from these studies to improve propagation in zoological parks, private and public propagation facilities, and research institutions. Researchers need to study the control of ovulation, egg formation, and oviposition in the species of nondomestic birds that lay very few eggs in a season, hold eggs in the oviduct for longer intervals, or differ in other ways from the more thoroughly studied domestic birds. Other techniques that would enhance propagation for nondomestlc birds include tissue culture of cloned embryonic cells, cryopreservation of embryos

  6. A Guide to Precision Calculations in Dyson's Hierarchical Scalar Field Theory

    CERN Document Server

    Godina, J J; Oktay, M B; Niermann, S M

    1998-01-01

    The goal of this article is to provide a practical method to calculate, in a scalar theory, accurate numerical values of the renormalized quantities which could be used to test any kind of approximate calculation. We use finite truncations of the Fourier transform of the recursion formula for Dyson's hierarchical model in the symmetric phase to perform high-precision calculations of the unsubtracted Green's functions at zero momentum in dimension 3, 4, and 5. We use the well-known correspondence between statistical mechanics and field theory in which the large cut-off limit is obtained by letting beta reach a critical value beta_c (with up to 16 significant digits in our actual calculations). We show that the round-off errors on the magnetic susceptibility grow like (beta_c -beta)^{-1} near criticality. We show that the systematic errors (finite truncations and volume) can be controlled with an exponential precision and reduced to a level lower than the numerical errors. We justify the use of the truncation f...

  7. Guide to precision calculations in Dyson close-quote s hierarchical scalar field theory

    International Nuclear Information System (INIS)

    The goal of this article is to provide a practical method to calculate, in a scalar theory, accurate numerical values of the renormalized quantities which could be used to test any kind of approximate calculation. We use finite truncations of the Fourier transform of the recursion formula for Dyson close-quote s hierarchical model in the symmetric phase to perform high-precision calculations of the unsubtracted Green close-quote s functions at zero momentum in dimension 3, 4, and 5. We use the well-known correspondence between statistical mechanics and field theory in which the large cutoff limit is obtained by letting β reach a critical value βc (with up to 16 significant digits in our actual calculations). We show that the round-off errors on the magnetic susceptibility grow like (βc-β)-1 near criticality. We show that the systematic errors (finite truncations and volume) can be controlled with an exponential precision and reduced to a level lower than the numerical errors. We justify the use of the truncation for calculations of the high-temperature expansion. We calculate the dimensionless renormalized coupling constant corresponding to the 4-point function and show that when β→βc, this quantity tends to a fixed value which can be determined accurately when D=3 (hyperscaling holds), and goes to zero like [Ln(βc-β)]-1 when D=4. copyright 1998 The American Physical Society

  8. Molecular characterization of Indonesia avian influenza virus

    Directory of Open Access Journals (Sweden)

    N.L.P.I. Dharmayanti

    2005-06-01

    Full Text Available Avian influenza outbreaks in poultry have been reported in Java island since August 2003. A total of 14 isolates of avian influenza virus has been isolated from October 2003 to October 2004. The viruses have been identified as HPAI H5N1 subtype. All of them were characterized further at genetic level and also for their pathogenicity. Phylogenetic analysis showed all of the avian influenza virus isolates were closely related to avian influenza virus from China (A/Duck/China/E319-2/03(H5N1. Molecular basis of pathogenicity in HA cleavage site indicated that the isolates of avian influenza virus have multiple basic amino acid (B-X-B-R indicating that all of the isolates representing virulent avian influenza virus (highly pathogenic avian influenza virus.

  9. Protection of avian influenza (AI vaccines for poultry against infection of field isolates A/Chicken/West Java/Smi-Pat/2006 and A/Chicken/West Java/Smi-Mae/2008 under laboratory condition

    Directory of Open Access Journals (Sweden)

    Risa Indriani

    2011-06-01

    Full Text Available The aim of this research was to study level of protection of avian influenza (AI commercial vaccines available in Indonesia (subtipe H5N1, H5N2 and H5N9 against infection of HPAI field isolates of A/Chicken/West Java/Smi-Pat/2006 and A/Chicken/West Java/Smi-Mae/2008. There were 7 commercial vaccines used in this study, the each vaccines were injected in to 3 weeks old of layer chichickenen intramuscularly. At 3 weeks after vaccination, ten chichickenens from each group were challenged separately with the A/Chicken/West Java/Smi-Pat/2006 and A/Chicken/West Java/Smi-Mae/2008 isolates intranasaly with dose 106 ELD50 per 0,1 ml per chicken. Ten unvaccinated chicken were included in the challenge test as control. The study demonstrate that the AI vaccines with subtipe H5N1 protected chicken (100% against virus of A/Chicken/West Java/Smi-Pat/2006 and 90-100% against virus A/Chicken/West Java/Smi-Mae/2008. Viral shedding were not seen by 2 days post challenge. The AI vaccines with subtipe H5N2 protected chicken at 20-30% against virus of A/Chicken/West Java/Smi-Pat/2006 and protected chicken at 70-100% against virus of A/Chicken/West Java/Smi-Mae/2008. Viral shedding still detected at 8 days post challenge. The AI vaccines AI with subtipe H5N9 did not protect chicken (0% against virus A/Chicken/West Java/Smi-Pat/2006 and protected chicken at 50% against virus A/Chicken/West Java/Smi-Mae/2008. Viral shedding still detected by 8 days post challenge. This study concluded that AI vaccines with subtipe H5N1 are better than other AI subtipe vaccines in preventing HPAI virus A/Chicken/West Java/Smi-Pat/2006 dan A/Chicken/West Java/Smi-Mae/2008 infections under laboratory condition.

  10. Design, Development and Preliminary Student Evaluation of Virtual Field Guides as aids to teaching and learning in the Earth sciences

    Science.gov (United States)

    Stott, Tim

    2010-05-01

    In Universities the benefits of teaching and learning through fieldwork has been brought under closer examination in recent years (e.g. Andrews et al., 2003) and the notion of supporting fieldwork in the Geography, Earth and Environmental Science (GEES) disciplines has been gathering momentum over the past decade as evidenced by conferences on ‘Supporting fieldwork using information technology' (Maskall et al., 2007) and a Higher Education Academy GEES Virtual Fieldwork Conference at University of Worcester (May 2007). Virtual environments and e-learning resources have been shown to help students become active rather than passive learners by appealing to their multi-sensory learning ability with interactive media (Fletcher et al., 2002; 2007). Research on glacial and fluvial processes has been conducted since 2003 by Liverpool John Moores University (LJMU) staff, sometimes in collaboration with other Universities, at field sites in the French Alps, Swiss Alps and Cariboo Mountains in British Columbia. A virtual field guide (VFG) (www.virtualalps.co.uk) has been developed which uses maps, site photos, panorama movies, video clips, a google earth tour, student exercises using hydrological and glacial datasets collected in the field and revision exercises. A preliminary evaluation of this learning resource has been carried out with two groups of LJMU students and an article written (Stott et al. 2009a). The Ingleton Waterfalls VFG (http://www.ljmu.ac.uk/BIE/ingleton/) was developed by LJMU staff to meet the needs of Foundation degree and undergraduate students. A workshop was presented at the Earth Science Teachers Association 2008 Annual Conference at LJMU, and a subsequent article written (Stott et al. 2009b). The final section of this presentation will summarise some staff perspectives and raises some questions and issues concerned with development and accessibility of VFGs in the light of new developments of a ‘semantic web' at LJMU (Carmichael, 2009). Andrews

  11. Influenza vaccines for avian species

    Science.gov (United States)

    Beginning in Southeast Asia, in 2003, a multi-national epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity an...

  12. OFFLU Network on Avian Influenza

    OpenAIRE

    Edwards, Steven

    2006-01-01

    OFFLU is the name of the network of avian influenza expertise inaugurated jointly in 2005 by the Food and Agriculture Organization of the United Nations and the World Organisation for Animal Health. Achievements and constraints to date and plans for the future are described.

  13. Avian influenza: the political economy of disease control in Cambodia.

    Science.gov (United States)

    Ear, Sophal

    2011-01-01

    Abstract In the wake of avian flu outbreaks in 2004, Cambodia received $45 million in commitments from international donors to help combat the spread of animal and human influenza, particularly avian influenza (H5N1). How countries leverage foreign aid to address the specific needs of donors and the endemic needs of the nation is a complex and nuanced issue throughout the developing world. Cambodia is a particularly compelling study in pandemic preparedness and the management of avian influenza because of its multilayered network of competing local, national, and global needs, and because the level of aid in Cambodia represents approximately $2.65 million per human case-a disproportionately high number when compared with neighbors Vietnam and Indonesia. This paper examines how the Cambodian government has made use of animal and human influenza funds to protect (or fail to protect) its citizens and the global community. It asks how effective donor and government responses were to combating avian influenza in Cambodia, and what improvements could be made at the local and international level to help prepare for and respond to future outbreaks. Based on original interviews, a field survey of policy stakeholders, and detailed examination of Cambodia's health infrastructure and policies, the findings illustrate that while pandemic preparedness has shown improvements since 2004, new outbreaks and human fatalities accelerated in 2011, and more work needs to be done to align the specific goals of funders with the endemic needs of developing nations. PMID:22702421

  14. Avian influenza: the political economy of disease control in Cambodia.

    Science.gov (United States)

    Ear, Sophal

    2011-01-01

    Abstract In the wake of avian flu outbreaks in 2004, Cambodia received $45 million in commitments from international donors to help combat the spread of animal and human influenza, particularly avian influenza (H5N1). How countries leverage foreign aid to address the specific needs of donors and the endemic needs of the nation is a complex and nuanced issue throughout the developing world. Cambodia is a particularly compelling study in pandemic preparedness and the management of avian influenza because of its multilayered network of competing local, national, and global needs, and because the level of aid in Cambodia represents approximately $2.65 million per human case-a disproportionately high number when compared with neighbors Vietnam and Indonesia. This paper examines how the Cambodian government has made use of animal and human influenza funds to protect (or fail to protect) its citizens and the global community. It asks how effective donor and government responses were to combating avian influenza in Cambodia, and what improvements could be made at the local and international level to help prepare for and respond to future outbreaks. Based on original interviews, a field survey of policy stakeholders, and detailed examination of Cambodia's health infrastructure and policies, the findings illustrate that while pandemic preparedness has shown improvements since 2004, new outbreaks and human fatalities accelerated in 2011, and more work needs to be done to align the specific goals of funders with the endemic needs of developing nations.

  15. Optically encoded nanoprobes using single walled carbon nanotube as the building scaffold for magnetic field guided cell imaging.

    Science.gov (United States)

    Wang, Hong; Wang, Zhuyuan; Ye, Minglang; Zong, Shenfei; Li, Mingyue; Chen, Peng; Ma, Xueqin; Cui, Yiping

    2014-02-01

    We construct a novel fluorescent, surface enhanced Raman scattering (SERS) encoded and magnetic nanoprobe for live cell imaging. To fabricate this nanoprobe, single walled carbon nanotube (SWNT) is used as the building scaffold while gold nanoparticles (Au NPs), superparamagnetic iron oxide nanoparticles (SPIONs) and quantum dots (QDs) are employed as the building blocks. Here, Au NPs serve as the SERS substrate and QDs act as the fluorescent agent. Au NPs and SPIONs are first adsorbed on the SWNT via electrostatic interactions. Then a silica layer is coated on the SWNT. Finally, QDs are attached on the silica shell. With such a structure, various optical signals can be readily encoded to the nanoprobe simply by using different Raman molecules and QDs with different emission wavelengths. Experimental results show that the as-prepared nanoprobe exhibits well fluorescence and SERS performance. Furthermore, in vitro experiments demonstrate that the nanoprobe can fulfill magnetic field guided fluorescence and SERS dual mode imaging of live cells. As a fascinating optical encoding material and a multifunctional nanoplatform, the presented nanoprobe holds genuine potential in future biosensing applications.

  16. The Radical Pair Mechanism and the Avian Chemical Compass: Quantum Coherence and Entanglement

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yiteng [Purdue Univ., West Lafayette, IN (United States); Kais, Sabre [Purdue Univ., West Lafayette, IN (United States); Berman, Gennady Petrovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-02

    We review the spin radical pair mechanism which is a promising explanation of avian navigation. This mechanism is based on the dependence of product yields on 1) the hyperfine interaction involving electron spins and neighboring nuclear spins and 2) the intensity and orientation of the geomagnetic field. One surprising result is that even at ambient conditions quantum entanglement of electron spins can play an important role in avian magnetoreception. This review describes the general scheme of chemical reactions involving radical pairs generated from singlet and triplet precursors; the spin dynamics of the radical pairs; and the magnetic field dependence of product yields caused by the radical pair mechanism. The main part of the review includes a description of the chemical compass in birds. We review: the general properties of the avian compass; the basic scheme of the radical pair mechanism; the reaction kinetics in cryptochrome; quantum coherence and entanglement in the avian compass; and the effects of noise. We believe that the quantum avian compass can play an important role in avian navigation and can also provide the foundation for a new generation of sensitive and selective magnetic-sensing nano-devices.

  17. Transfection by DNAs of avian erythroblastosis virus and avian myelocytomatosis virus strain MC29.

    OpenAIRE

    Copeland, N G; Cooper, G M

    1980-01-01

    Chicken embryo fibroblasts and NIH 3T3 mouse cells were transformable by DNAs of chicken cells infected with avian myelocytomatosis virus strain MC29 or with avian erythroblastosis virus. Transfection of chicken cells appeared to require replication of MC29 or avian erythroblastosis virus in the presence of a nontransforming helper virus. In contrast, NIH 3T3 cells transformed by MC29 or avian erythroblastosis virus DNA contained only replication-defective transforming virus genomes.

  18. Quantum coherence and sensitivity of avian magnetoreception

    CERN Document Server

    Bandyopadhyay, Jayendra N; Kaszlikowski, Dagomir

    2012-01-01

    Migratory birds and other species have the ability to navigate by sensing the geomagnetic field. Recent experiments indicate that the essential process in the navigation takes place in bird's eye and uses chemical reaction involving molecular ions with unpaired electron spins (radical pair). Sensing is achieved via geomagnetic-dependent dynamics of the spins of the unpaired electrons. Here we utilize the results of all behavioral experiments conducted on European Robins to argue that the average life-time of the radical pair is of the order of a microsecond and therefore agrees with experimental estimations of this parameter for cryptochrome --- a pigment believed to form the radical pairs. We also found a reasonable parameter regime where sensitivity of the avian compass is enhanced by environmental noise, showing that long coherence time is not required for navigation and may even spoil it.

  19. Preliminary research on overmoded high-power millimeter-wave Cerenkov generator with dual-cavity reflector in low guiding magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Hu; Wu, Ping [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an, Shaanxi 710024 (China); Chen, Changhua; Ning, Hui; Tan, Weibing; Teng, Yan; Shi, Yanchao; Song, Zhimin; Cao, Yibing; Du, Zhaoyu [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an, Shaanxi 710024 (China)

    2015-12-15

    This paper presents preliminary research on a V-band overmoded Cerenkov generator with dual-cavity reflector operating in a low guiding magnetic field. It is found that the fluctuation of the electron envelope in the low guiding magnetic field can be predicted using an equivalent coaxial model of a foilless diode, and a dual-cavity reflector based on the model matching method can provide strong reflection at the front end of the overmoded structures so that any microwave power that leaks into the diode region can be effectively suppressed. Numerical simulations indicate that the control of the beam envelope and the use of the dual-cavity reflector ease generator operation in the low guiding magnetic field. In the experimental research, the fluctuation of the annular electron beam with the outer radius of 7.5 mm measures approximately 0.7 mm, which is in good agreement with the theoretical results. The disturbance caused by power leaking from the overmoded slow wave structure is eliminated by the dual-cavity reflector. With accurate fabrication and assembly processes, an operating frequency of 61.6 GHz is attained by the fifth harmonic heterodyne method, and the output power is measured to be approximately 123 MW by the far-field measurement method at a diode voltage of 445 kV, a beam current of 4.45 kA, and under a guiding magnetic field of 1.45 T. The output mode is measured using an array of neon flash bulbs, and the pulse shortening phenomenon is both observed and analyzed.

  20. Preliminary research on overmoded high-power millimeter-wave Cerenkov generator with dual-cavity reflector in low guiding magnetic field

    International Nuclear Information System (INIS)

    This paper presents preliminary research on a V-band overmoded Cerenkov generator with dual-cavity reflector operating in a low guiding magnetic field. It is found that the fluctuation of the electron envelope in the low guiding magnetic field can be predicted using an equivalent coaxial model of a foilless diode, and a dual-cavity reflector based on the model matching method can provide strong reflection at the front end of the overmoded structures so that any microwave power that leaks into the diode region can be effectively suppressed. Numerical simulations indicate that the control of the beam envelope and the use of the dual-cavity reflector ease generator operation in the low guiding magnetic field. In the experimental research, the fluctuation of the annular electron beam with the outer radius of 7.5 mm measures approximately 0.7 mm, which is in good agreement with the theoretical results. The disturbance caused by power leaking from the overmoded slow wave structure is eliminated by the dual-cavity reflector. With accurate fabrication and assembly processes, an operating frequency of 61.6 GHz is attained by the fifth harmonic heterodyne method, and the output power is measured to be approximately 123 MW by the far-field measurement method at a diode voltage of 445 kV, a beam current of 4.45 kA, and under a guiding magnetic field of 1.45 T. The output mode is measured using an array of neon flash bulbs, and the pulse shortening phenomenon is both observed and analyzed

  1. Molecular characterization of Indonesia avian influenza virus

    OpenAIRE

    N.L.P.I Dharmayanti; R Damayanti; R Indriani; A Wiyono; R.M.A Adjid

    2005-01-01

    Avian influenza outbreaks in poultry have been reported in Java island since August 2003. A total of 14 isolates of avian influenza virus has been isolated from October 2003 to October 2004. The viruses have been identified as HPAI H5N1 subtype. All of them were characterized further at genetic level and also for their pathogenicity. Phylogenetic analysis showed all of the avian influenza virus isolates were closely related to avian influenza virus from China (A/Duck/China/E319-2/03(H5N1). Mo...

  2. Avian Influenza infection in Human

    Directory of Open Access Journals (Sweden)

    Mohan. M

    2008-08-01

    Full Text Available Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds.All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in humans. There is no evidence, to date that efficient human to human transmission of H5N1 strain has occurred and very often. Efficient transmission among humans is a key property of pandemic strains and a property that the avian H5N1 and H9N2 viruses apparently lacked. The biological and molecular basis for effective aerosol transmission among humans is not known. The virus can improve its transmissibility among humans via two principal mechanisms. The first is a “reassortment” event, in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig.Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread. The second mechanism is a more gradual process of adaptive mutation, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early. As the number of human infections grows, the risk increases that a new virus subtype could emerge, triggering an influenza pandemic. Humans as well as swine must now be considered a potential mixing vessel for the generation of such a virus. This link between widespread infection in poultry and increased risk of human

  3. Climate change and avian influenza

    OpenAIRE

    Gilbert, Marius; Slingenbergh, Jan; Xiao, Xiangming

    2008-01-01

    This paper discusses impacts of climate change on the ecology of avian influenza viruses (AI viruses), which presumably co-evolved with migratory water birds, with virus also persisting outside the host in subarctic water bodies. Climate change would almost certainly alter bird migration, influence the AI virus transmission cycle and directly affect virus survival outside the host. The joint, net effects of these changes are rather unpredictable, but it is likely that AI virus circulation in ...

  4. Gender determination of avian embryo

    Science.gov (United States)

    Daum, Keith A.; Atkinson, David A.

    2002-01-01

    Disclosed is a method for gender determination of avian embryos. During the embryo incubation process, the outer hard shells of eggs are drilled and samples of allantoic fluid are removed. The allantoic fluids are directly introduced into an ion mobility spectrometer (IMS) for analysis. The resulting spectra contain the relevant marker peaks in the positive or negative mode which correlate with unique mobilities which are sex-specific. This way, the gender of the embryo can be determined.

  5. Simulating Avian Wingbeats and Wakes

    OpenAIRE

    Parslew, Ben

    2012-01-01

    Analytical models of avian flight have previously been used to predict mechanical and metabolic power consumption during cruise. These models are limited, in that they neglect details of wing kinematics, and model power by assuming a fixed or rotary wing (actuator disk) weight support mechanism. Theoretical methods that incorporate wing kinematics potentially offer more accurate predictions of power consumption by calculating instantaneous aerodynamic loads on the wing. However, the success o...

  6. Using EGEE against avian flu

    CERN Multimedia

    2006-01-01

    During April 2006 avian flu was spreading across the world with the potential of turning into a pandemic, a drug to treat the deadly H5N1 strain was needed. Such a task required the huge processing power provided by EGEE, which analysed 300 000 possible drug components for their suitability. This map shows the network of computer centres and their activity during this time.

  7. Gigawatt-class microwave generation from a novel Ku-band coaxial transit-time oscillator with low guiding magnetic field

    Science.gov (United States)

    Ling, Junpu; Zhang, Jiande; He, Juntao; Jiang, Tao; Song, Lili

    2016-10-01

    A non-uniform buncher and a depth-tunable collector have been proposed to improve the power capacity and conversion efficiency of the coaxial foilless transit-time oscillator (TTO) in our previous work. Recently, our Ku-band coaxial TTO with low guiding magnetic field is improved by employing them, and the related experimental investigations are carried out on the TORCH-01 accelerator. It is shown that the non-uniform buncher plays a key role in the enhancement of microwave pulse duration. The influences of the collector's depth on characteristics of the device indicate that the conversion efficiency can be improved by optimizing the collector's depth in the experiments. With the diode voltage 460 kV, the beam current 8.7 kA, and the guiding magnetic field of 0.6 T, a radiation power of 1 GW with the conversion efficiency of 25% at 14.3 GHz is generated by our improved TTO. The output pulse duration is 26 ns and no obvious pulse shortening is observed. The experimental results demonstrate the abilities of this improved Ku-band device to generate gigawatt-class Ku-band microwave with low guiding magnetic field.

  8. The effect of guide-field and boundary conditions on the features and signatures of collisionless magnetic reconnection in a stressed X-point collapse

    Science.gov (United States)

    Graf von der Pahlen, J.; Tsiklauri, D.

    2015-12-01

    Magnetic X-point collapse is investigated using a 2.5D fully relativistic particle-in-cell simulation, with varying strengths of guide-field as well as open and closed boundary conditions. In the zero guide-field case we discover a new signature of Hall-reconnection in the out-of-plane magnetic field, namely an octupolar pattern, as opposed to the well-studied quadrupolar out-of-plane field of reconnection. The emergence of the octupolar components was found to be caused by ion currents and is a general feature of X-point collapse. In a comparative study of tearing-mode reconnection, signatures of octupolar components are found only in the out-flow region. It is argued that space-craft observations of magnetic fields at reconnection sites may be used accordingly to identify the type of reconnection [1][2]. Further, initial oscillatory reconnection is observed, prior to reconnection onset, generating electro-magnetic waves at the upper-hybrid frequency, matching solar flare progenitor emission. When applying a guide-field, in both open and closed boundary conditions, thinner dissipation regions are obtained and the onset of reconnection is increasingly delayed. Investigations with open boundary conditions show that, for guide-fields close to the strength of the in-plane field, shear flows emerge, leading to the formation of electron flow vortices and magnetic islands [3]. Asymmetries in the components of the generalised Ohm's law across the dissipation region are observed. Extended in 3D geometry, it is shown that locations of magnetic islands and vortices are not constant along the height of the current-sheet. Vortices formed on opposite sites of the current-sheet travel in opposite directions along it, leading to a criss-cross vortex pattern. Possible instabilities resulting from this specific structure formation are to be investigated [4].[1] J. Graf von der Pahlen and D. Tsiklauri, Phys. Plasmas 21, 060705 (2014), [2] J. Graf von der Pahlen and D. Tsiklauri

  9. Chemical compass for avian magnetoreception as a quantum coherent device

    CERN Document Server

    Cai, Jianming

    2013-01-01

    It is known that more than 50 species use the Earth's magnetic field for orientation and navigation. Intensive studies particularly behavior experiments with birds provide support for a chemical compass based on magnetically sensitive free radical reactions as a source of this sense. However, the fundamental question of whether and how quantum coherence plays an essential role in such a chemical compass model of avian magnetoreception yet remains controversial. Here, we show that the essence of the chemical compass model can be understood in analogy to a quantum interferometer exploiting quantum coherence. Within the framework of quantum metrology, we quantify quantum coherence and demonstrate that it is a resource for chemical magnetoreception. Our results allow us to understand and predict how various factors can affect the performance of a chemical compass from the unique perspective of quantum coherence assisted metrology. This represents a crucial step to affirm avian magnetoreception as an example of qu...

  10. Avian rotavirus enteritis - an updated review.

    Science.gov (United States)

    Dhama, Kuldeep; Saminathan, Mani; Karthik, Kumaragurubaran; Tiwari, Ruchi; Shabbir, Muhammad Zubair; Kumar, Naveen; Malik, Yashpal Singh; Singh, Raj Kumar

    2015-01-01

    Rotaviruses (RVs) are among the leading causes of enteritis and diarrhea in a number of mammalian and avian species, and impose colossal loss to livestock and poultry industry globally. Subsequent to detection of rotavirus in mammalian hosts in 1973, avian rotavirus (AvRV) was first reported in turkey poults in USA during 1977 and since then RVs of group A (RVA), D (RVD), F (RVF) and G (RVG) have been identified around the globe. Besides RVA, other AvRV groups (RVD, RVF and RVG) may also contribute to disease. However, their significance has yet to be unraveled. Under field conditions, co-infection of AvRVs occurs with other infectious agents such as astroviruses, enteroviruses, reoviruses, paramyxovirus, adenovirus, Salmonella, Escherichia coli, cryptosporidium and Eimeria species prospering severity of disease outcome. Birds surviving to RV disease predominantly succumb to secondary bacterial infections, mostly E. coli and Salmonella spp. Recent developments in molecular tools including state-of-the-art diagnostics and vaccine development have led to advances in our understanding towards AvRVs. Development of new generation vaccines using immunogenic antigens of AvRV has to be explored and given due importance. Till now, no effective vaccines are available. Although specific as well as sensitive approaches are available to identify and characterize AvRVs, there is still need to have point-of-care detection assays to review disease burden, contemplate new directions for adopting vaccination and follow improvements in public health measures. This review discusses AvRVs, their epidemiology, pathology and pathogenesis, immunity, recent trends in diagnostics, vaccines, therapeutics as well as appropriate prevention and control strategies.

  11. Monte Carlo study of the impact of a magnetic field on the dose distribution in MRI-guided HDR brachytherapy using Ir-192

    Science.gov (United States)

    Beld, E.; Seevinck, P. R.; Lagendijk, J. J. W.; Viergever, M. A.; Moerland, M. A.

    2016-09-01

    In the process of developing a robotic MRI-guided high-dose-rate (HDR) prostate brachytherapy treatment, the influence of the MRI scanner’s magnetic field on the dose distribution needs to be investigated. A magnetic field causes a deflection of electrons in the plane perpendicular to the magnetic field, and it leads to less lateral scattering along the direction parallel with the magnetic field. Monte Carlo simulations were carried out to determine the influence of the magnetic field on the electron behavior and on the total dose distribution around an Ir-192 source. Furthermore, the influence of air pockets being present near the source was studied. The Monte Carlo package Geant4 was utilized for the simulations. The simulated geometries consisted of a simplified point source inside a water phantom. Magnetic field strengths of 0 T, 1.5 T, 3 T, and 7 T were considered. The simulation results demonstrated that the dose distribution was nearly unaffected by the magnetic field for all investigated magnetic field strengths. Evidence was found that, from a dose perspective, the HDR prostate brachytherapy treatment using Ir-192 can be performed safely inside the MRI scanner. No need was found to account for the magnetic field during treatment planning. Nevertheless, the presence of air pockets in close vicinity to the source, particularly along the direction parallel with the magnetic field, appeared to be an important point for consideration.

  12. Avian influenza and the poultry trade

    OpenAIRE

    Nicita, Alessandro

    2008-01-01

    Because of high mortality rates, high rates of contagion, and the possibility of cross-species infection to mammals including humans, high pathogenic avian influenza is a major concern both to consumers and producers of poultry. The implications of the avian influenza for international poultry markets are large and include the loss of consumer confidence, loss of competitiveness, loss of m...

  13. Atypical Avian Influenza (H5N1)

    OpenAIRE

    Apisarnthanarak, Anucha; Kitphati, Rungrueng; Thongphubeth, Kanokporn; Patoomanunt, Prisana; Anthanont, Pimjai; Auwanit, Wattana; Thawatsupha, Pranee; Chittaganpitch, Malinee; Saeng-Aroon, Siriphan; Waicharoen, Sunthareeya; Apisarnthanarak, Piyaporn; Storch, Gregory A.; Mundy, Linda M.; Fraser, Victoria J.

    2004-01-01

    We report the first case of avian influenza in a patient with fever and diarrhea but no respiratory symptoms. Avian influenza should be included in the differential diagnosis for patients with predominantly gastrointestinal symptoms, particularly if they have a history of exposure to poultry.

  14. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2011-05-03

    ... (76 FR 4046-4056, Docket No. APHIS-2006-0074) an interim rule that amended the regulations governing... Inspection Service 9 CFR Parts 93, 94, and 95 RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal... products from regions where any subtype of highly pathogenic avian influenza is considered to exist....

  15. Mechanisms of avian songs and calls

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye

    2008-01-01

    The avian vocal organ, the syrinx, is a specialized structure located rather inaccessibly in an air sac close to the heart where the trachea bifurcates into the two primary bronchi. The syrinx of different avian taxa varies so much in position and morphology that it has been used for taxonomy. It...

  16. Electron acceleration in the inverse free electron laser with a helical wiggler by axial magnetic field and ion-channel guiding

    Institute of Scientific and Technical Information of China (English)

    Reza Khazaeinezhad; Mahdi Esmaeilzadeh

    2012-01-01

    Electron acceleration in the inverse free electron laser (IFEL) with a helical wiggler in the presence of ion-channel guiding and axial magnetic field is investigated in this article.The effects of tapering wiggler amplitude and axial magnetic field are calculated for the electron acceleration.In free electron lasers,electron beams lose energy through radiation while in IFEL electron beams gain energy from the laser.The equation of electron motion and the equation of energy exchange between a single electron and electromagnetic waves are derived and then solved numerically using the fourth order Runge-Kutta method.The tapering effects of a wiggler magnetic field on electron acceleration are investigated and the results show that the electron acceleration increases in the case of a tapered wiggler magnetic field with a proper taper constant.

  17. Molecular patterns of avian influenza A viruses

    Institute of Scientific and Technical Information of China (English)

    KOU Zheng; LEI FuMin; WANG ShengYue; ZHOU YanHong; LI TianXian

    2008-01-01

    Avian influenza A viruses could get across the species barrier and be fatal to humans. Highly patho-genic avian influenza H5N1 virus was an example. The mechanism of interspecies transmission is not clear as yet. In this research, the protein sequences of 237 influenza A viruses with different subtypes were transformed into pseudo-signals. The energy features were extracted by the method of wavelet packet decomposition and used for virus classification by the method of hierarchical clustering. The clustering results showed that five patterns existed in avian influenza A viruses, which associated with the phenotype of interspecies transmission, and that avian viruses with patterns C and E could across species barrier and those with patterns A, B and D might not have the abilities. The results could be used to construct an early warning system to predict the transmissibility of avian influenza A viruses to humans.

  18. Avian use of introduced plants: ornithologist records illuminate interspecific associations and research needs.

    Science.gov (United States)

    Aslan, Clare E; Rejmánek, Marcel

    2010-06-01

    Introduced species have the potential to impact processes central to the organization of ecological communities. Although hundreds of nonnative plant species have naturalized in the United States, only a small percentage of these have been studied in their new biotic communities. Their interactions with resident (native and introduced) bird species remain largely unexplored. As a group, citizen scientists such as ornithologists possess a wide range of experiences. They may offer insights into the prevalence and form of bird interactions with nonnative plants on a broad geographic scale. We surveyed 173 ornithologists from four U.S. states, asking them to report observations of bird interactions with nonnative plants. The primary goal of the survey was to obtain information useful in guiding future empirical research. In all, 1143 unique bird-plant interactions were reported, involving 99 plant taxa and 168 bird species. Forty-seven percent of reported interactions concerned potential dispersal (feeding on seeds or fruits). Remaining "habitat interactions" involved bird use of plants for nesting, perching, woodpecking, gleaning, and other activities. We utilized detrended correspondence analysis to ordinate birds with respect to the plants they reportedly utilize. Results illuminate the new guilds formed by these interactions. We assessed the existing level of knowledge about invasiveness of those plants reported most often in feeding interactions, identifying information gaps for biological invasions research priority. To exemplify the usefulness of citizen science data, we utilized survey results to guide field research on invasiveness in some of these plant species and observed both qualitatively and quantitatively strong agreement between survey reports and our empirical data. Questionnaire reports are therefore heuristically informative for the fields of both avian ecology and invasion biology. PMID:20597286

  19. Physiologically driven avian vocal synthesizer

    Science.gov (United States)

    Sitt, Jacobo D.; Arneodo, Ezequiel M.; Goller, Franz; Mindlin, Gabriel B.

    2010-03-01

    In this work, we build an electronic syrinx, i.e., a programmable electronic device capable of integrating biomechanical model equations for the avian vocal organ in order to synthesize song. This vocal prosthesis is controlled by the bird’s neural instructions to respiratory and the syringeal motor systems, thus opening great potential for studying motor control and its modification by sensory feedback mechanisms. Furthermore, a well-functioning subject-controlled vocal prosthesis can lay the foundation for similar devices in humans and thus provide directly health-related data and procedures.

  20. Avian Influenza Virus: The Threat of A Pandemic

    OpenAIRE

    Shih-Cheng Chang; Yi-Ying Cheng; Shin-Ru Shih

    2006-01-01

    The 1918 influenza A virus pandemic caused a death toll of 40~50 million. Currently,because of the widespread dissemination of the avian influenza virus (H5N1), there is a highrisk of another pandemic. Avian species are the natural hosts for numerous subtypes ofinfluenza A viruses; however, the highly pathogenic avian influenza virus (HPAI) is not onlyextremely lethal to domestic avian species but also can infect humans and cause death. Thisreview discusses why the avian influenza virus is co...

  1. Giving Students Control over Their Learning; from Self-guided Museum Visits and Field Trips to Using Scanning Technology to Link Content to Earth Samples

    Science.gov (United States)

    Kirkby, K. C.; Phipps, M.

    2011-12-01

    While it may seem counterintuitive, sometimes stepping back is one of the more effective pedagogical approaches instructors can make. On museum visits, an instructor's presence fundamentally alters students' experiences and can curtail student learning by limiting questions or discouraging students from exploring their own interests. Students often rely on the instructor and become passive observers, rather than engaged learners. As an alternative to instructor-led visits, self-guided student explorations of museum exhibits proved to be both popular and pedagogically effective. On pre-instruction and post-instruction surveys, these ungraded, self-guided explorations match or exceed the efficacy of traditional graded lab instruction and completely eclipse gains normally achieved by traditional lecture instruction. In addition, these explorations achieve the remarkable goal of integrating undergraduate earth science instruction into students' social lives. Based on the success of the self-guided museum explorations, this fall saw the debut of an attempt to expand this concept to field experiences. A self-guided student field exploration of Saint Anthony Falls focuses on the intersections of geological processes with human history. Students explore the waterfalls' evolution, its early interpretation by 18th and 19th century Dakota and Euro-America societies, and its subsequent social and economic impacts on Upper Midwest societies. Self-guided explorations allow students to explore field settings on their own or with friends and family in a more relaxed manner. At the same time, these explorations give students control over, and responsibility for, their own learning - a powerful pedagogical approach. Student control over their learning is also the goal of an initiative to use scanning technologies, such as linear bar codes, 2D barcodes and radio-frequency identification (RFID), to revolutionize sample identification and study. Scanning technology allows students to

  2. Enhancement of a Virtual Geology Field Guide of Georgia Initiative Using Gigapan© and ArcGIS Online's Story Map

    Science.gov (United States)

    Mobasher, K.; Turk, H. J.; Witherspoon, W.; Tate, L.; Hoynes, J.

    2015-12-01

    A GIS geology geodatabase of Georgia was developed using ArcGIS 10.2. The geodatabase for each physiographic provinces of Georgia contains fields designed to store information regarding geologic features. Using ArcGIS online, the virtual field guide is created which provides an interactive learning experience for students to allow in real time photography, description, mapping and sharing their observations with the instructor and peers. Gigapan© facilitates visualizing geologic features at different scales with high resolutions and in their larger surrounding context. The classroom applications of the Gigapan© are limitless when teaching students the entire range of geologic structures from showcasing crystalline structures of minerals to understanding the geological processes responsible for formation of an entire mountain range. The addition of the Story Map enhances the virtual experience when you want to present a geo-located story point narrative featuring images or videos. The virtual field component and supplementary Gigapan© imagery coupled with Story Map added significantly to the detailed realism of virtual field guide further allowing students to more fully understand geological concepts at various scales. These technologies peaked students interest and facilitated their learning and preparation to function more effectively in the geosciences by developing better observations and new skills. These technologies facilitated increased student engagement in the geosciences by sharing, enhancing and transferring lecture information to actual field knowledge and experiences. This enhanced interactive learning experience not only begins to allow students to understand and recognize geologic features in the field but also increased their collaboration, enthusiasm and interest in the discipline. The increased interest and collaboration occurred as students assisted in populating a geologic geodatabase of Georgia.

  3. Aerodynamic Loss Co-Relations and Flow- Field Investigations of a Transonic Film- Cooled Nozzle Guide Vane

    OpenAIRE

    Leung, Pak Wing

    2015-01-01

    Over the last two decades, most developed countries have reached a consensus that greener energy production is necessary for the world, due to the climate changes and limited fossil fuel resources. More efficient turbine is desirable and can be archived by higher turbine-inlet temperature (TIT). However, it is difficult for nozzle guide vane (NGV), which is the first stage after combustion chamber, to withstand a very high temperature. Thus, cooling methods such as film cooling have to be imp...

  4. Avian influenza: an osteopathic component to treatment

    OpenAIRE

    Hruby, Raymond J; Hoffman, Keasha N

    2007-01-01

    Avian influenza is an infection caused by the H5N1 virus. The infection is highly contagious among birds, and only a few known cases of human avian influenza have been documented. However, healthcare experts around the world are concerned that mutation or genetic exchange with more commonly transmitted human influenza viruses could result in a pandemic of avian influenza. Their concern remains in spite of the fact that the first United States vaccine against the H5N1 virus was recently approv...

  5. Landscape attributes driving avian influenza virus circulation in the Lake Alaotra region of Madagascar

    Directory of Open Access Journals (Sweden)

    Laure Guerrini

    2014-05-01

    Full Text Available While the spatial pattern of the highly pathogenic avian influenza H5N1 virus has been studied throughout Southeast Asia, little is known on the spatial risk factors for avian influenza in Africa. In the present paper, we combined serological data from poultry and remotely sensed environmental factors in the Lake Alaotra region of Madagascar to explore for any association between avian influenza and landscape variables. Serological data from cross-sectional surveys carried out on poultry in 2008 and 2009 were examined together with a Landsat 7 satellite image analysed using supervised classification. The dominant landscape features in a 1-km buffer around farmhouses and distance to the closest water body were extracted. A total of 1,038 individual bird blood samples emanating from 241 flocks were analysed, and the association between avian influenza seroprevalence and these landcape variables was quantified using logistic regression models. No evidence of the presence of H5 or H7 avian influenza subtypes was found, suggesting that only low pathogenic avian influenza (LPAI circulated. Three predominant land cover classes were identified around the poultry farms: grassland savannah, rice paddy fields and wetlands. A significant negative relationship was found between LPAI seroprevalence and distance to the closest body of water. We also found that LPAI seroprevalence was higher in farms characterised by predominant wetlands or rice landscapes than in those surrounded by dry savannah. Results from this study suggest that if highly pathogenic avian influenza H5N1 virus were introduced in Madagascar, the environmental conditions that prevail in Lake Alaotra region may allow the virus to spread and persist.

  6. Mercury risk to avian piscivores across western United States and Canada

    Science.gov (United States)

    Jackson, Allyson K.; Evers, David C.; Eagles-Smith, Collin A.; Ackerman, Josh; Willacker, James J.; Elliott, John E.; Lepak, Jesse M; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west limits the distribution of avian piscivore species, complicating broad comparisons across the region. Mercury risk to avian piscivores was evaluated across the western United States and Canada using a suite of avian piscivore species representing a variety of foraging strategies that together occur broadly across the region. Prey fish Hg concentrations were size-adjusted to the preferred size class of the diet for each avian piscivore (Bald Eagle = 36 cm, Osprey = 30 cm, Common and Yellow-billed Loon = 15 cm, Western and Clark's Grebe = 6 cm, and Belted Kingfisher = 5 cm) across each species breeding range. Using a combination of field and lab-based studies on Hg effect in a variety of species, wet weight blood estimates were grouped into five relative risk categories including: background ( 3 μg/g). These risk categories were used to estimate potential mercury risk to avian piscivores across the west at a 1 degree-by-1 degree grid cell resolution. Avian piscivores foraging on larger-sized fish generally were at a higher relative risk to Hg. Habitats with a relatively high risk included wetland complexes (e.g., prairie pothole in Saskatchewan), river deltas (e.g., San Francisco Bay, Puget Sound, Columbia River), and arid lands (Great Basin and central Arizona). These results indicate that more intensive avian piscivore sampling is needed across Western North America to generate a more robust assessment of exposure risk.

  7. Magnetic resonance-guided upper abdominal biopsies in a high-field wide-bore 3-T MRI system: feasibility, handling, and needle artefacts

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Jens-Peter; Langner, Soenke; Hegenscheid, Katrin; Hosten, Norbert; Puls, Ralf [Ernst Moritz Arndt University of Greifswald, Department of Radiology, Greifswald (Germany); Evert, Matthias [Ernst Moritz Arndt University of Greifswald, Department of Pathology, Greifswald (Germany); Kickhefel, Antje [Siemens Healthcare, Erlangen (Germany)

    2010-10-15

    To investigate the feasibility and handling of abdominal MRI-guided biopsies in a 3-T MRI system. Over a 1-year period, 50 biopsies were obtained in 47 patients with tumours of the upper abdominal organs guided by 3-T MRI with a large-bore diameter of 70 cm. Lesions in liver (47), spleen (1) and kidney (2) were biopsied with a coaxial technique using a 16-G biopsy needle guided by a T1-weighted three-dimensional gradient recalled echo volumetric interpolated breath-hold examination (T1w-3D-GRE-VIBE) sequence. Sensitivity, specificity, accuracy, complication rate, interventional complexity, room/intervention time and needle artefacts were determined. A sensitivity of 0.93, specificity of 1.0 and accuracy of 0.94 were observed. Three patients required a rebiopsy. There was a minor complications rate of 13.6%, and no major complications were observed. Histopathology revealed 38 malignant lesions, and 3-month follow-up confirmed 9 benign lesions. Mean lesion diameter was 3.4 {+-} 3.1 cm (50% being smaller than 2 cm). Mean needle tract length was 10.8 {+-} 3.3 cm. Median room time was 42.0 {+-} 19.8 min and intervention time 9.3 {+-} 8.1 min. Needle artefact size was about 9-fold greater for perpendicular access versus access parallel to the main magnetic field. Biopsies of the upper abdomen can be performed with great technical success and easy handling because of the large-bore diameter. The MRI-guided biopsy needle had an acceptable susceptibility artefact at 3 T. However future research must aim to reduce the susceptibility effects of the biopsy systems. (orig.)

  8. Avian magnetoreception: elaborate iron mineral containing dendrites in the upper beak seem to be a common feature of birds.

    Directory of Open Access Journals (Sweden)

    Gerald Falkenberg

    Full Text Available The magnetic field sensors enabling birds to extract orientational information from the Earth's magnetic field have remained enigmatic. Our previously published results from homing pigeons have made us suggest that the iron containing sensory dendrites in the inner dermal lining of the upper beak are a candidate structure for such an avian magnetometer system. Here we show that similar structures occur in two species of migratory birds (garden warbler, Sylvia borin and European robin, Erithacus rubecula and a non-migratory bird, the domestic chicken (Gallus gallus. In all these bird species, histological data have revealed dendrites of similar shape and size, all containing iron minerals within distinct subcellular compartments of nervous terminals of the median branch of the Nervus ophthalmicus. We also used microscopic X-ray absorption spectroscopy analyses to identify the involved iron minerals to be almost completely Fe III-oxides. Magnetite (Fe II/III may also occur in these structures, but not as a major Fe constituent. Our data suggest that this complex dendritic system in the beak is a common feature of birds, and that it may form an essential sensory basis for the evolution of at least certain types of magnetic field guided behavior.

  9. Relativistic Guiding Center Equations

    Energy Technology Data Exchange (ETDEWEB)

    White, R. B. [PPPL; Gobbin, M. [Euratom-ENEA Association

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  10. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2012-06-12

    ... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056... Register on May 3, 2011 (76 FR 24793, Docket No. APHIS-2006-0074), we reopened the comment period for...

  11. Montana 2006 Avian Influenza Surveillance Project Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During the summer of 2006, the U.S. Department of Agriculture (USDA) and the U.S. Fish and Wildlife Service (USFWS) initiated a nationwide avian influenza...

  12. Avian Habitat Data; Seward Peninsula, Alaska, 2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data product contains avian habitat data collected on the Seward Peninsula, Alaska, USA, during 21 May – 10 June 2012. We conducted replicated 10-min surveys...

  13. Clipping the wings of avian influenza

    OpenAIRE

    2012-01-01

    Up to now, the threat of avian influenza has been lessened by effective animal husbandry methods. However, the public health community is trying to ensure enough measures are in place to prevent a possible pandemic. Jane Parry reports.

  14. Avian models in teratology and developmental toxicology.

    Science.gov (United States)

    Smith, Susan M; Flentke, George R; Garic, Ana

    2012-01-01

    The avian embryo is a long-standing model for developmental biology research. It also has proven utility for toxicology research both in ovo and in explant culture. Like mammals, avian embryos have an allantois and their developmental pathways are highly conserved with those of mammals, thus avian models have biomedical relevance. Fertile eggs are inexpensive and the embryo develops rapidly, allowing for high-throughput. The chick genome is sequenced and significant molecular resources are available for study, including the ability for genetic manipulation. The absence of a placenta permits the direct study of an agent's embryotoxic effects. Here, we present protocols for using avian embryos in toxicology research, including egg husbandry and hatch, toxicant delivery, and assessment of proliferation, apoptosis, and cardiac structure and function.

  15. Avian protection plan : Lostwood National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Lostwood National Wildlife Refuge (LNWR) initiated this Avian Protection Plan (APP) in 2003 to protect birds from potential electrocution hazards on the...

  16. Field Trip Guide to Serpentinite, Silica-Carbonate Alteration, and Related Hydrothermal Activity in the Clear Lake Region, California

    Energy Technology Data Exchange (ETDEWEB)

    Fraser Goff; George Guthrie

    1999-06-01

    This guide is designed to familiarize scientists with the geology, structure, alteration, and fluids typical of California serpentinites for purposes of carbon dioxide sequestration (Lackner et al., 1995). Goff et al. (1997) and Goff and Lackner (1998) describe the geology and geochemistry of some of the serpentinites from this area. Mechanisms of silica-carbonate alteration were outlined by Barnes et al. (1973). Donnelly-Nolan et al. (1993) most recently reviewed relations between regional hydrothermal alteration and Quarternary volcanic activity. Stanley et al. (1998) summarized geophysical characteristics of the region.

  17. THE PROPERTIES OF GUIDED ELECTROMAGNETIC FIELD MODES ON THE GaAs-BASED FIBER GLASS AND LASERS

    Directory of Open Access Journals (Sweden)

    Mustafa TEMİZ

    1999-03-01

    Full Text Available On the lasers or fiber optic communication electromagnetic waves are transmitted by confining and guiding between special layer's or fiber glass respectively. It is desired that electric and magnetic waves are in the active region of the lasers and in the core of the fiber glass. It is obtained by making more larger the of refractive index of the regions. On this work, the behavior and varying of the electric and magnetic waves and the effects on the electromagnetic waves in the fiber glass and lasers are investigated.

  18. Estimation of permeability tensor and dielectric permittivity of ferrites using a wave guide method under a dc magnetic field

    Directory of Open Access Journals (Sweden)

    Tsiachristos I.

    2014-07-01

    Full Text Available Using a vector network analyzer equipped with a calibrated rectangular wave guide the electric permittivity and the element of the magnetic permeability tensor for Y3Fe5O12, ZnFe2O4 and NiFe2O4 are measured. The electric permittivity can be estimated from the body resonances (d = nλ/2 if a sufficient long sample is used. The estimation of the magnetic permeability tensors’ parameters can be estimated comparing the experimental results with computer simulations using the magnetic properties of the materials as derived from the magnetic measurements.

  19. A review of avian probiotics.

    Science.gov (United States)

    Smith, Jeanne Marie

    2014-06-01

    Probiotics have been used in poultry for decades and have become common in the pet bird industry. Desirable characteristics of probiotic organisms are that they are nonpathogenic, have the ability to adhere to intestinal epithelial cells, have the ability to colonize and reproduce in the host, have the ability to be host-specific, survive transit through the gastrointestinal tract and exposure to stomach acid and bile, produce metabolites that inhibit or kill pathogenic bacteria, modulate gastrointestinal immune responses, and survive processing and storage. Purported benefits in birds are disease prevention and promotion of growth. Recommendations for use in avian species are for periodic use to replenish normal flora, use after antibiotic therapy to reestablish normal flora, and use during periods of stress to counter effects of immunosuppression. PMID:25115036

  20. Three-Dimensional MHD Magnetic Reconnection Simulations with Finite Guide Field: Proposal of the Shock-Evoking Positive-Feedback Model

    CERN Document Server

    Wang, Shuoyang; Isobe, Hiroaki

    2015-01-01

    Using a three-dimensional magnetohydrodynamic model, we simulate the magnetic reconnection in a single current sheet. We assume a finite guide field, a random perturbation on the velocity field and uniform resistivity. Our model enhances the reconnection rate relative to the classical Sweet-Parker model in the same configuration. The efficiency of magnetic energy conversion is increased by interactions between the multiple tearing layers coexisting in the global current sheet. This interaction, which forms a positive-feedback system, arises from coupling of the inflow and outflow regions in different layers across the current sheet. The coupling accelerates the elementary reconnection events, thereby enhancing the global reconnection rate. The reconnection establishes flux tubes along each tearing layer. Slow-mode shocks gradually form along the outer boundaries of these tubes, further accelerating the magnetic energy conversion.Such positive-feedback system is absent in two-dimensional simulation, three-dime...

  1. Oseltamivir in human avian influenza infection

    OpenAIRE

    Smith, James R.

    2010-01-01

    Avian influenza A viruses continue to cause disease outbreaks in humans, and extrapulmonary infection is characteristic. In vitro studies demonstrate the activity of oseltamivir against avian viruses of the H5, H7 and H9 subtypes. In animal models of lethal infection, oseltamivir treatment and prophylaxis limit viral replication and improve survival. Outcomes are influenced by the virulence of the viral strain, dosage regimen and treatment delay; it is also critical for the compound to act sy...

  2. Avian influenza: an emerging pandemic threat.

    Science.gov (United States)

    Jin, Xian Wen; Mossad, Sherif B

    2005-12-01

    While we are facing the threat of an emerging pandemic from the current avian flu outbreak in Asia, we have learned important traits of the virus responsible for the 1918 Spanish influenza pandemic that made it so deadly. By using stockpiled antiviral drugs effectively and developing an effective vaccine, we can be in a better position than ever to mitigate the global impact of an avian influenza pandemic. PMID:16392727

  3. Optimal usage of cone beam computed tomography system with different field of views in image guided radiotherapy (IGRT

    Directory of Open Access Journals (Sweden)

    Narayana Venkata Naga Madhusudhana Sresty

    2015-09-01

    Full Text Available Purpose: To find methods for optimal usage of XVI (X-ray volume imaging system in Elekta synergy linear accelerator with different field of views for same lesion in order to minimize patient dose due to imaging.Methods: 20 scans of 2 individual patients with ca sigmoid colon and ca lung were used in this study. Kilo voltage collimators with medium field of view were used as per the preset information. Images were reconstructed for another collimator with small field of view. The set up errors were evaluated with XVI software. Shift results of both methods were compared. Results: Variation in treatment set up errors with M20 and S20 collimators were ≤ 0.2 mm in translational and 0.30 in rotational shifts. Results showed almost equal translational and rotational shifts in both medium and small field of views with different collimators in all the scans. Visualization of target and surrounding structures were good enough and sufficient for XVI auto matching.Conclusion: Imaging with small field of view results less patient dose compared with medium or large field of views. It is Suggestible to use collimators with small field of view wherever possible. In this study, collimators with small field of view were sufficient for both patients though the preset information indicated medium field of view. But, it always depends on the area required for matching purpose. So, individual selection is important than preset information in the XVI system.

  4. Avian Distribution and Habitat, Published in 2010, 1:12000 (1in=1000ft) scale, GaDNR/Wildlife Resources Division.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Avian Distribution and Habitat dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Field Observation information as of 2010....

  5. Ecology and conservation biology of avian malaria

    Science.gov (United States)

    LaPointe, Dennis A.; Atkinson, Carter T.; Samuel, Michael D.

    2012-01-01

    Avian malaria is a worldwide mosquito-borne disease caused by Plasmodium parasites. These parasites occur in many avian species but primarily affect passerine birds that have not evolved with the parasite. Host pathogenicity, fitness, and population impacts are poorly understood. In contrast to continental species, introduced avian malaria poses a substantial threat to naive birds on Hawaii, the Galapagos, and other archipelagoes. In Hawaii, transmission is maintained by susceptible native birds, competence and abundance of mosquitoes, and a disease reservoir of chronically infected native birds. Although vector habitat and avian communities determine the geographic distribution of disease, climate drives transmission patterns ranging from continuous high infection in warm lowland forests, seasonal infection in midelevation forests, and disease-free refugia in cool high-elevation forests. Global warming is expected to increase the occurrence, distribution, and intensity of avian malaria across this elevational gradient and threaten high-elevation refugia, which is the key to survival of many susceptible Hawaiian birds. Increased temperatures may have already increased global avian malaria prevalence and contributed to an emergence of disease in New Zealand.

  6. Native Americans: Subject Guide.

    Science.gov (United States)

    Bonanni, Mimmo; Etter, Patricia A.

    This annotated subject guide lists reference material that deals with Native Americans and is available in the Arizona State University Libraries. Entries were published 1933-98, but mostly in the 1980s-90s. The guide is not comprehensive, but rather a selective list of resources useful for researching a topic in a variety of fields. The guide…

  7. Medical Assisting Program Guide.

    Science.gov (United States)

    Georgia Univ., Athens. Dept. of Vocational Education.

    This guide presents the standard curriculum for technical institutes in Georgia. The curriculum addresses the minimum competencies for a medical assisting program. The program guide is designed to relate primarily to the development of those skills needed by individuals in the medical assisting field, such as medical law and ethics, typing,…

  8. Tuning the Field Trip: Audio-Guided Tours as a Replacement for 1-Day Excursions in Human Geography

    Science.gov (United States)

    Wissmann, Torsten

    2013-01-01

    Educators are experiencing difficulties with 1-day field trips in human geography. Instead of teaching students how to apply theory in the field and learn to "sense" geography in everyday life, many excursions have degraded into tourist-like events where lecturers try to motivate rather passive students against a noisy urban backdrop.…

  9. Field Trip to the Moon. LRO/LCROSS Edition. Informal Educator's Guide. EG-2008-09-48-MSFC

    Science.gov (United States)

    National Aeronautics and Space Administration (NASA), 2007

    2007-01-01

    Field Trip to the Moon uses an inquiry-based learning approach that fosters team building and introduces participants to careers in science and engineering. The program components include the Field Trip to the Moon DVD [not included here], Lunar Reconnaissance Orbiter (LRO)/Lunar Crater Observation and Sensing Satellite (LCROSS) Activities, and…

  10. Avian magnetic compass can be tuned to anomalously low magnetic intensities.

    Science.gov (United States)

    Winklhofer, Michael; Dylda, Evelyn; Thalau, Peter; Wiltschko, Wolfgang; Wiltschko, Roswitha

    2013-07-22

    The avian magnetic compass works in a fairly narrow functional window around the intensity of the local geomagnetic field, but adjusts to intensities outside this range when birds experience these new intensities for a certain time. In the past, the geomagnetic field has often been much weaker than at present. To find out whether birds can obtain directional information from a weak magnetic field, we studied spontaneous orientation preferences of migratory robins in a 4 µT field (i.e. a field of less than 10 per cent of the local intensity of 47 µT). Birds can adjust to this low intensity: they turned out to be disoriented under 4 µT after a pre-exposure time of 8 h to 4 µT, but were able to orient in this field after a total exposure time of 17 h. This demonstrates a considerable plasticity of the avian magnetic compass. Orientation in the 4 µT field was not affected by local anaesthesia of the upper beak, but was disrupted by a radiofrequency magnetic field of 1.315 MHz, 480 nT, suggesting that a radical-pair mechanism still provides the directional information in the low magnetic field. This is in agreement with the idea that the avian magnetic compass may have developed already in the Mesozoic in the common ancestor of modern birds.

  11. Dermoscopy-guided reflectance confocal microscopy of skin using high-NA objective lens with integrated wide-field color camera

    Science.gov (United States)

    Dickensheets, David L.; Kreitinger, Seth; Peterson, Gary; Heger, Michael; Rajadhyaksha, Milind

    2016-02-01

    Reflectance Confocal Microscopy, or RCM, is being increasingly used to guide diagnosis of skin lesions. The combination of widefield dermoscopy (WFD) with RCM is highly sensitive (~90%) and specific (~ 90%) for noninvasively detecting melanocytic and non-melanocytic skin lesions. The combined WFD and RCM approach is being implemented on patients to triage lesions into benign (with no biopsy) versus suspicious (followed by biopsy and pathology). Currently, however, WFD and RCM imaging are performed with separate instruments, while using an adhesive ring attached to the skin to sequentially image the same region and co-register the images. The latest small handheld RCM instruments offer no provision yet for a co-registered wide-field image. This paper describes an innovative solution that integrates an ultra-miniature dermoscopy camera into the RCM objective lens, providing simultaneous wide-field color images of the skin surface and RCM images of the subsurface cellular structure. The objective lens (0.9 NA) includes a hyperhemisphere lens and an ultra-miniature CMOS color camera, commanding a 4 mm wide dermoscopy view of the skin surface. The camera obscures the central portion of the aperture of the objective lens, but the resulting annular aperture provides excellent RCM optical sectioning and resolution. Preliminary testing on healthy volunteers showed the feasibility of combined WFD and RCM imaging to concurrently show the skin surface in wide-field and the underlying microscopic cellular-level detail. The paper describes this unique integrated dermoscopic WFD/RCM lens, and shows representative images. The potential for dermoscopy-guided RCM for skin cancer diagnosis is discussed.

  12. Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

    Science.gov (United States)

    Coates, Peter S.; Casazza, Michael L.; Halstead, Brian J.; Fleskes, Joseph P.; Laughlin, James A.

    2011-01-01

    Radar systems designed to detect avian activity at airfields are useful in understanding factors that influence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfield was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was first explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24-hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coefficients) averaged across models and a relatively simple calculation for safety officers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fit. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refine these inference models and improve our understanding of factors that influence avian activity, which is necessary to inform

  13. EPA QUICK REFERENCE GUIDES

    Science.gov (United States)

    EPA Quick Reference Guides are compilations of information on chemical and biological terrorist agents. The information is presented in consistent format and includes agent characteristics, release scenarios, health and safety data, real-time field detection, effect levels, samp...

  14. Magnetic microscopy guide

    OpenAIRE

    Harald Brune

    2005-01-01

    Magnetic Microscopy of Nanostructures is an excellent introduction for newcomers and, for those working in the field, can be used as a guide before seeking more up-to-date literature, saysHarald Brune.

  15. Avian Point Count Locations - Dahomey NWR 2007-2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Map depicts locations of avian point counts conducted on Dahomey in 2007 and 2008. Actual point count data are contained in the avian knowledge network database

  16. Avian Influenza A (H7N9) Virus

    Science.gov (United States)

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A (H7N9) Virus Language: English Español Recommend ...

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

    Science.gov (United States)

    Stoffer, Philip W.; Messina, Paula

    2002-01-01

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

  18. Back-calculation method shows that within-flock transmission of highly pathogenic avian influenza (H7N7) virus in the Netherlands is not influenced by housing risk factors

    NARCIS (Netherlands)

    Bos, M.E.H.; Nielen, M.; Koch, G.; Bouma, A.; Jong, de M.C.M.; Stegeman, J.A.

    2009-01-01

    To optimize control of an avian influenza outbreak knowledge of within-flock transmission is needed. This study used field data to estimate the transmission rate parameter (ß) and the influence of risk factors on within-flock transmission of highly pathogenic avian influenza (HPAI) H7N7 virus in the

  19. Geology of the Greenwater Range, and the dawn of Death Valley, California—Field guide for the Death Valley Natural History Conference, 2013

    Science.gov (United States)

    Calzia, J.P.; Rämö, O.T.; Jachens, Robert; Smith, Eugene; Knott, Jeffrey

    2016-05-02

    Much has been written about the age and formation of Death Valley, but that is one—if not the last—chapter in the fascinating geologic history of this area. Igneous and sedimentary rocks in the Greenwater Range, one mountain range east of Death Valley, tell an earlier story that overlaps with the formation of Death Valley proper. This early story has been told by scientists who have studied these rocks for many years and continue to do so. This field guide was prepared for the first Death Valley Natural History Conference and provides an overview of the geology of the Greenwater Range and the early history (10–0 Ma) of Death Valley.

  20. Geology of the Greenwater Range, and the dawn of Death Valley, California—Field guide for the Death Valley Natural History Conference, 2013

    Science.gov (United States)

    Calzia, J.P.; Rämö, O.T.; Jachens, Robert; Smith, Eugene; Knott, Jeffrey

    2016-01-01

    Much has been written about the age and formation of Death Valley, but that is one—if not the last—chapter in the fascinating geologic history of this area. Igneous and sedimentary rocks in the Greenwater Range, one mountain range east of Death Valley, tell an earlier story that overlaps with the formation of Death Valley proper. This early story has been told by scientists who have studied these rocks for many years and continue to do so. This field guide was prepared for the first Death Valley Natural History Conference and provides an overview of the geology of the Greenwater Range and the early history (10–0 Ma) of Death Valley.

  1. 6th Regional Symposium of the International Fossil Algae Associaton, Milano, July 1-5, 2009. Abstracts and Field trip guide-book.

    Directory of Open Access Journals (Sweden)

    Francesca Benzoni

    2009-10-01

    Full Text Available The 6th Regional Symposium of the IFAA held in Milano, from 1 to 5 July 2009, follows the 5th Regional meeting in Ferrara (2005 and the 9th International Symposium held in Zagreb (2007. The Symposium was jointly organized by the University of Milano-Bicocca, Department of Geological Sciences and Geotechnologies, and by the University of Genova, Dip.Te.Ris. Geologists and paleontologists of the University of Genova have been studying coralline-rich outcrops of the Tertiary Piedmont Basin since the end of the XIX Century (G. Rovereto, M. Airoldi, S. Conti, V.I. Mastrorilli, producing the scientific descriptions of dozens of new species, the types of which are housed in the Genova Dip.Te.Ris.This volume represetn the abstract book and the field trip guide book edited for the symposium.

  2. Proceedings of National Avian-Wind Power Planning Meeting IV

    Energy Technology Data Exchange (ETDEWEB)

    NWCC Avian Subcommittee

    2001-05-01

    OAK-B135 The purpose of the fourth meeting was to (1) share research and update research conducted on avian wind interactions (2) identify questions and issues related to the research results, (3) develop conclusions about some avian/wind power issues, and (4) identify questions and issues for future avian research.

  3. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, William [Brooks Engineering, Vacaville, CA (United States); Basso, Thomas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Coddington, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-10-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  4. Incorporating ecology and social system into formal hypotheses to guide field studies of color vision in primates.

    Science.gov (United States)

    Bunce, John A

    2015-05-01

    The X-linked gene polymorphism responsible for the variable color vision of most Neotropical monkeys and some lemurs is thought to be maintained by balancing selection, such that trichromats have an advantage over dichromats for some ecologically important task(s). However, evidence for such an advantage in wild primate populations is equivocal. The purpose of this study is to refine a hypothesis for a trichromat advantage by tailoring it to the ecology of territorial primates with female natal dispersal, such that dispersing trichromatic females have a foraging and, by extension, survival advantage over dichromats. I then examine the most practical way to test this hypothesis using field data. Indirect evidence in support of the hypothesis may take the form of differences in genotype frequencies among life stages and differences in disperser food item encounter rates. A deterministic evolutionary matrix population model and a stochastic model of food patch encounter rates are constructed to investigate the magnitude of such differences and the likelihood of statistical detection using field data. Results suggest that, although the sampling effort required to detect the hypothesized genotype frequency differences is impractical, a field study of reasonable scope may be able to detect differences in disperser foraging rates. This study demonstrates the utility of incorporating socioecological details into formal hypotheses during the planning stages of field studies of primate color vision. PMID:25690845

  5. Dynamic and static control of the optical phase of guided p-polarized light for near-field focusing at large angles of incidence

    CERN Document Server

    Huang, Danhong; Wellems, L David; Mozer, Henry; Gumbs, Godfrey; Cardimona, D A; Maradudin, A A

    2013-01-01

    Both dynamic and static approaches are proposed and investigated for controlling the optical phase of a p-polarized light wave that is guided through a surface-patterned metallic structure with subwavelength features. For dynamic control, field-induced transparency (FIT) from photo-excited electrons in a slit-embedded atomic system show up within a narrow frequency window for modulating the intensity of focused transmitted light in the near-field region. Based on the electromagnetic coupling, this is facilitated by surface plasmons between the two FIT-atom embedded slits. For static control, the role of surface curvature is obtained for focused transmitted light passing through a Gaussian-shaped metallic microlens embedded with a linear array of slits, in addition to a negative light-refraction pattern, which is associated with higher-diffraction modes of light, under a large angle of incidence in the near-field region. Most interesting, however, this anomalous negative light-refraction pattern becomes suppre...

  6. Time-resolved electric field measurements during and after the initialization of a kHz plasma jet—from streamers to guided streamers

    Science.gov (United States)

    Slikboer, Elmar; Guaitella, Olivier; Sobota, Ana

    2016-06-01

    This work presents the investigation of a 30 kHz operated atmospheric pressure plasma jet impinging a dielectric BSO-crystal, allowing time-resolved electric field measurements based on the Pockels effect. Observations indicate that from the time the voltage is applied, the plasma first develops through unstable branching before a stable periodic behavior is established. This initialization of the plasma jet suggests the importance of the build-up of leftover ionization, which creates a preferred pathway for the streamer-like discharges. After initialization the time and spatially resolved electric field of guided ionization waves induced in the crystal is obtained, showing a highly periodic charging and discharging at the surface of the crystal. When the ionization wave arrives at the crystal charge is deposited and constant electric fields are generated for approximately 14 μs. Then a (back) discharge will remove the deposited charge at the surface, related to the moment when the applied voltage changes polarity and it agrees with imaging reported on in other literature.

  7. The Use of Satellite Imagery to Guide Field Plot Sampling Scheme for Biomass Estimation in Ghanaian Forest

    Science.gov (United States)

    Sah, B. P.; Hämäläinen, J. M.; Sah, A. K.; Honji, K.; Foli, E. G.; Awudi, C.

    2012-07-01

    Accurate and reliable estimation of biomass in tropical forest has been a challenging task because a large proportion of forests are difficult to access or inaccessible. So, for effective implementation of REDD+ and fair benefit sharing, the proper designing of field plot sampling schemes plays a significant role in achieving robust biomass estimation. The existing forest inventory protocols using various field plot sampling schemes, including FAO's regular grid concept of sampling for land cover inventory at national level, are time and human resource intensive. Wall to wall LiDAR scanning is, however, a better approach to assess biomass with high precision and spatial resolution even though this approach suffers from high costs. Considering the above, in this study a sampling design based on a LiDAR strips sampling scheme has been devised for Ghanaian forests to support field plot sampling. Using Top-of-Atmosphere (TOA) reflectance value of satellite data, Land Use classification was carried out in accordance with IPCC definitions and the resulting classes were further stratified, incorporating existing GIS data of ecological zones in the study area. Employing this result, LiDAR sampling strips were allocated using systematic sampling techniques. The resulting LiDAR strips represented all forest categories, as well as other Land Use classes, with their distribution adequately representing the areal share of each category. In this way, out of at total area of 15,153km2 of the study area, LiDAR scanning was required for only 770 km2 (sampling intensity being 5.1%). We conclude that this systematic LiDAR sampling design is likely to adequately cover variation in above-ground biomass densities and serve as sufficient a-priori data, together with the Land Use classification produced, for designing efficient field plot sampling over the seven ecological zones.

  8. On the structure of guide magnetic field in the inertia-driven magnetic reconnection with the presence of shear flow

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinpour, M.; Mohammadi, M. A. [Department of Plasma Physics, Faculty of Physics, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2013-11-15

    The effect of equilibrium shear flow on the structure of out-of-plane magnetic field is analytically investigated in the two-fluid magnetohydrodynamic (MHD) regimes of the collisionless tearing instability, where the electron inertia breaks the frozen-in condition. Our scaling analysis reveals that the Alfvénic and sub-Alfvénic shear flows cannot significantly modify the linear regimes of applicability. In addition, we show that the structure of out-of-plane magnetic field can either be quadrupolar or non-quadrupolar in Hall-MHD regimes. In particular, both types of structures can dominate at β < 1 (β is the ratio of plasma kinetic pressure to the pressure in the magnetic field) depending on the value of the normalized ion inertial skin depth. This conclusion, however, is in contradiction to the claim presented by Rogers et al. [J. Geophys. Res. 108, A3 (2003)], which states that the quadrupolar structure cannot appear at β < 1. The reasons of this disagreement are discussed in our study.

  9. Target volume delineation and field setup. A practical guide for conformal and intensity-modulated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nancy Y. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States). Radiation Oncology; Lu, Jiade J. (eds.) [National Univ. Health System, Singapore (Singapore). Dept. of Radiation Oncology; National Univ. of Singapore (Singapore). Dept. of Medicine

    2013-03-01

    Practical handbook on selection and delineation of tumor volumes and fields for conformal radiation therapy, including IMRT. Helpful format facilitating use on a step-by-step basis in daily practice. Designed to ensure accurate coverage of commonly encountered tumors along their routes of spread. This handbook is designed to enable radiation oncologists to appropriately and confidently delineate tumor volumes/fields for conformal radiation therapy, including intensity-modulated radiation therapy (IMRT), in patients with commonly encountered cancers. The orientation of this handbook is entirely practical, in that the focus is on the illustration of clinical target volume (CTV) delineation for each major malignancy. Each chapter provides guidelines and concise knowledge on CTV selection for a particular disease, explains how the anatomy of lymphatic drainage shapes the selection of the target volume, and presents detailed illustrations of volumes, slice by slice, on planning CT images. While the emphasis is on target volume delineation for three-dimensional conformal therapy and IMRT, information is also provided on conventional radiation therapy field setup and planning for certain malignancies for which IMRT is not currently suitable.

  10. Draft Genome Sequences of Two Avian Pathogenic Escherichia coli Strains of Clinical Importance, E44 and E51

    DEFF Research Database (Denmark)

    Ronco, Troels; Stegger, Marc; Andersen, Paal S;

    2016-01-01

    Avian pathogenic Escherichia coli strains have remarkable impacts on animal welfare and the production economy in the poultry industry worldwide. Here, we present the draft genomes of two isolates from chickens (E44 and E51) obtained from field outbreaks and subsequently investigated for their po......Avian pathogenic Escherichia coli strains have remarkable impacts on animal welfare and the production economy in the poultry industry worldwide. Here, we present the draft genomes of two isolates from chickens (E44 and E51) obtained from field outbreaks and subsequently investigated...

  11. Avian influenza surveillance of wild birds

    Science.gov (United States)

    Slota, Paul

    2007-01-01

    The President's National Strategy for Pandemic Influenza directs federal agencies to expand the surveillance of United States domestic livestock and wildlife to ensure early warning of hightly pathogenic avian influenza (HPAI) in the U.S. The immediate concern is a potential introduction of HPAI H5N1 virus into the U.S. The presidential directive resulted in the U.S. Interagency Strategic Plan for Early Detection of H5N1 Highly Pathogenic Avian Influenza in Wild Migratory Birds (referred to as the Wild Bird Surveillance Plan or the Plan).

  12. Composting for Avian Influenza Virus Elimination

    OpenAIRE

    Elving, Josefine; Emmoth, Eva; Albihn, Ann; Vinnerås, Björn; Ottoson, Jakob

    2012-01-01

    Effective sanitization is important in viral epizootic outbreaks to avoid further spread of the pathogen. This study examined thermal inactivation as a sanitizing treatment for manure inoculated with highly pathogenic avian influenza virus H7N1 and bacteriophages MS2 and ϕ6. Rapid inactivation of highly pathogenic avian influenza virus H7N1 was achieved at both mesophilic (35°C) and thermophilic (45 and 55°C) temperatures. Similar inactivation rates were observed for bacteriophage ϕ6, while b...

  13. Avian Influenza: Should China Be Alarmed?

    OpenAIRE

    Su, Zhaoliang; Xu, Huaxi; Chen, Jianguo

    2007-01-01

    Avian influenza has emerged as one of the primary public health concern of the 21st century. Influenza strain H5N1 is capable of incidentally infecting humans and other mammals. Since their reemergence in 2003, highly pathogenic avian influenza A (H5N1) viruses have been transmitted from poultry to humans (by direct or indirect contact with infected birds) in several provinces of Mainland China, which has resulted in 22 cases of human infection and has created repercussions for the Chinese ec...

  14. Thermal emissivity of avian eggshells.

    Science.gov (United States)

    Björn, Lars Olof; Bengtson, Sven-Axel; Li, Shaoshan; Hecker, Christoph; Ullah, Saleem; Roos, Arne; Nilsson, Annica M

    2016-04-01

    The hypothesis has been tested that evolution has resulted in lower thermal emissivity of eggs of birds breeding openly in cold climates than of eggs of birds that nest under protective covering or in warmer climates. Directional thermal emissivity has been estimated from directional-hemispherical reflectance spectra. Due to several methodological difficulties the absolute emissivity is not accurately determined, but differences between species are obvious. Most notably, small waders of the genus Calidris, breeding in cold climates on the tundra, and in most cases with uniparental nest attendance, have low directional emissivity of their eggshells, about 0.92 when integration is carried out for wavelengths up to 16μm. Species belonging to Galloanserinae have the highest directional emissivity, about 0.96, of their eggs. No differences due to climate or breeding conditions were found within this group. Eggs of most other birds tested possess intermediate emissivity, but the values for Pica pica and Corvus corone cornix are as low as for Calidris. Large species-dependent differences in spectral reflectance were found at specific wavelengths. For instance, at 4.259μm the directional-hemispherical reflectance for galliforms range from 0.05 to 0.09, while for Fratercula arctica and Fulmarus glacialis it is about 0.3. The reflection peaks at 6.5 and 11.3μm due to calcite are differentially attenuated in different species. In conclusion, the hypothesis that evolution has resulted in lower thermal emissivity of bird eggs being exposed in cold climates is not supported by our results. The emissivity is not clearly related to nesting habits or climate, and it is unlikely that the small differences observed are ecologically important. The spectral differences between eggs that nevertheless exist should be taken into account when using infrared thermometers for estimating the surface temperature of avian eggs.

  15. Thermal emissivity of avian eggshells.

    Science.gov (United States)

    Björn, Lars Olof; Bengtson, Sven-Axel; Li, Shaoshan; Hecker, Christoph; Ullah, Saleem; Roos, Arne; Nilsson, Annica M

    2016-04-01

    The hypothesis has been tested that evolution has resulted in lower thermal emissivity of eggs of birds breeding openly in cold climates than of eggs of birds that nest under protective covering or in warmer climates. Directional thermal emissivity has been estimated from directional-hemispherical reflectance spectra. Due to several methodological difficulties the absolute emissivity is not accurately determined, but differences between species are obvious. Most notably, small waders of the genus Calidris, breeding in cold climates on the tundra, and in most cases with uniparental nest attendance, have low directional emissivity of their eggshells, about 0.92 when integration is carried out for wavelengths up to 16μm. Species belonging to Galloanserinae have the highest directional emissivity, about 0.96, of their eggs. No differences due to climate or breeding conditions were found within this group. Eggs of most other birds tested possess intermediate emissivity, but the values for Pica pica and Corvus corone cornix are as low as for Calidris. Large species-dependent differences in spectral reflectance were found at specific wavelengths. For instance, at 4.259μm the directional-hemispherical reflectance for galliforms range from 0.05 to 0.09, while for Fratercula arctica and Fulmarus glacialis it is about 0.3. The reflection peaks at 6.5 and 11.3μm due to calcite are differentially attenuated in different species. In conclusion, the hypothesis that evolution has resulted in lower thermal emissivity of bird eggs being exposed in cold climates is not supported by our results. The emissivity is not clearly related to nesting habits or climate, and it is unlikely that the small differences observed are ecologically important. The spectral differences between eggs that nevertheless exist should be taken into account when using infrared thermometers for estimating the surface temperature of avian eggs. PMID:27033033

  16. Economic effects of avian influenza on egg producers in Turkey

    Directory of Open Access Journals (Sweden)

    V Demircan

    2009-09-01

    Full Text Available This study determined the economic effects of avian influenza on the egg-production sector of Afyon Province, Turkey. Economic indicators were compared before and during the avian influenza outbreak. A questionnaire was conducted with 75 poultry farmers. Farms were divided into three groups according to their size. The profitability of the three farm size groups was compared during two study periods: before and during the avian influenza outbreak. The results indicate that, as compared to previous levels, farms experienced significantly reduced incomes during the avian influenza episode. While net income and profit margin were found to be negative in all three farm groups during the avian influenza period, only group I showed economic loss prior to avian influenza. Average net income per group was -19,576.14, -39,810.11, and -112,035.33 YTL respectively during the avian influenza outbreak, compared with prior incomes of -5,665.51, 8,422.92, and 16,3873.71 YTL (1 USD=1.43 YTL. The profit margin per egg during avian influenza was -0.029, -0.016, -0.010 YTL in group I, II, III, respectively, as compared to -0.007, 0.003, and 0.014 YTL/egg before avian influenza. It was found that, whereas larger farms were more profitable than small farms prior to the avian influenza period, larger farms suffered greater economic losses than small farms during avian influenza outbreak in the participating farms.

  17. Integral Field Spectroscopy of High-Redshift Star Forming Galaxies with Laser Guided Adaptive Optics: Evidence for Dispersion-Dominated Kinematics

    CERN Document Server

    Law, David R; Erb, Dawn K; Larkin, James E; Pettini, Max; Shapley, Alice E; Wright, Shelley A

    2007-01-01

    We present early results from an ongoing study of the kinematic structure of star-forming galaxies at redshift z ~ 2 - 3 using integral-field spectroscopy of rest-frame optical nebular emission lines in combination with Keck laser guide star adaptive optics (LGSAO). We show kinematic maps of 3 target galaxies Q1623-BX453, Q0449-BX93, and DSF2237a-C2 located at redshifts z = 2.1820, 2.0067, and 3.3172 respectively, each of which is well-resolved with a PSF measuring approximately 0.11 - 0.15 arcsec (~ 900 - 1200 pc at z ~ 2-3) after cosmetic smoothing. Neither galaxy at z ~ 2 exhibits substantial kinematic structure on scales >~ 30 km/s; both are instead consistent with largely dispersion-dominated velocity fields with sigma ~ 80 km/s along any given line of sight into the galaxy. In contrast, DSF2237a-C2 presents a well-resolved gradient in velocity over a distance of ~ 4 kpc with peak-to-peak amplitude of 140 km/s. It is unlikely that DSF2237a-C2 represents a dynamically cold rotating disk of ionized gas as ...

  18. Recent advances in the study of avian malaria: an overview with an emphasis on the distribution of Plasmodium spp in Brazil

    Directory of Open Access Journals (Sweden)

    Érika Martins Braga

    2011-08-01

    Full Text Available Avian malaria parasites (Plasmodium have a worldwide distribution except for Antarctica. They are transmitted exclusively by mosquito vectors (Diptera: Culicidae and are of particular interest to health care research due to their phylogenetic relationship with human plasmodia and their ability to cause avian malaria, which is frequently lethal in non-adapted avian hosts. However, different features of avian Plasmodium spp, including their taxonomy and aspects of their life-history traits, need to be examined in more detail. Over the last 10 years, ecologists, evolutionary biologists and wildlife researchers have recognized the importance of studying avian malaria parasites and other related haemosporidians, which are the largest group of the order Haemosporida by number of species. These studies have included understanding the ecological, behavioral and evolutionary aspects that arise in this wildlife host-parasite system. Molecular tools have provided new and exiting opportunities for such research. This review discusses several emerging topics related to the current research of avian Plasmodium spp and some related avian haemosporidians. We also summarize some important discoveries in this field and emphasize the value of using both polymerase chain reaction-based and microscopy-based methods in parallel for wildlife studies. We will focus on the genus Plasmodium, with an emphasis on the distribution and pathogenicity of these parasites in wild birds in Brazil.

  19. A Multi-Year Study of Mosquito Feeding Patterns on Avian Hosts in a Southeastern Focus of Eastern Equine Encephalitis Virus

    OpenAIRE

    Laura K Estep; Christopher J W McClure; BURKETT-CADENA, NATHAN D.; Hassan, Hassan K.; Hicks, Tyler L.; Thomas R Unnasch; Hill, Geoffrey E.

    2011-01-01

    Eastern equine encephalitis virus (EEEV) is a mosquito-borne pathogen that cycles in birds but also causes severe disease in humans and horses. We examined patterns of avian host use by vectors of EEEV in Alabama from 2001 to 2009 using blood-meal analysis of field-collected mosquitoes and avian abundance surveys. The northern cardinal (Cardinalis cardinalis) was the only preferred host (fed on significantly more than expected based on abundance) of Culiseta melanura, the enzootic vector of E...

  20. Practical aspects of vaccination of poultry against avian influenza virus.

    Science.gov (United States)

    Spackman, Erica; Pantin-Jackwood, Mary J

    2014-12-01

    Although little has changed in vaccine technology for avian influenza virus (AIV) in the past 20 years, the approach to vaccination of poultry (chickens, turkeys and ducks) for avian influenza has evolved as highly pathogenic AIV has become endemic in several regions of the world. Vaccination for low pathogenicity AIV is also becoming routine in regions where there is a high level of field challenge. In contrast, some countries will not use vaccination at all and some will only use it on an emergency basis during eradication efforts (i.e. stamping-out). There are pros and cons to each approach and, since every outbreak situation is different, no one method will work equally well in all situations. Numerous practical aspects must be considered when developing an AIV control program with vaccination as a component, such as: (1) the goals of vaccination must be defined; (2) the population to be vaccinated must be clearly identified; (3) there must be a plan to obtain and administer good quality vaccine in a timely manner and to achieve adequate coverage with the available resources; (4) risk factors for vaccine failure should be mitigated as much as possible; and, most importantly, (5) biosecurity must be maintained as much as possible, if not enhanced, during the vaccination period.

  1. Avian pox in a red-tailed hawk (Buteo jamaicensis)

    Energy Technology Data Exchange (ETDEWEB)

    Fitzner, R.E.; Miller, R.A. Pierce, C.A.; Rowe, S.E.

    1985-07-01

    Avian pox has been reported in at least 60 species of birds belonging to 20 different families. However, poxvirus infection in birds of prey is apparently uncommon. On 18 May 1981, an adult male red-tailed hawk was found on the US Department of Energy's Arid Land Ecology Reserve in Benton County, Washington. The bird was incapable of flight and was extremely thin. Nodular proliferations were noted on both feet and cutaneous scab-like lesions around the beak and eyes. The bird was killed in the field and submitted promptly to the diagnostic laboratory for necropsy. This report of pox infection in a free-living adult red-tailed hawk represents one of the few such cases reported in the US. The potential for spread of the virus to other hawks may occur particularly during the nesting season when an infected adult could conceivably pass the virus to a mate and nestlings by direct contact or fomites. Little is known of the natural of avian pox infection in birds of prey. In other birds it is generally considered mild and self-limiting; however, eye lesions resulting in impaired vision may lead to starvation.

  2. Avian response to bottomland hardwood reforestation: the first 10 years

    Science.gov (United States)

    Twedt, D.J.; Wilson, R.R.; Henne-Kerr, J.L.; Grosshuesch, D.A.

    2002-01-01

    Bttomland hardwood forests were planted on agricultural fields in Mississippi and Louisiana using either predominantly Quercus species (oaks) or Populus deltoides (eastern cottonwood). We assessed avian colonization of these reforested sites between 2 and 10 years after planting. Rapid vertical growth of cottonwoods (circa 2 - 3 m / yr) resulted in sites with forest structure that supported greater species richness of breeding birds, increased Shannon diversity indices, and supported greater territory densities than on sites planted with slower-growing oak species. Grassland birds (Spiza americana [Dickcissel], and Sturnella magna [Eastern Meadowlark]) were indicative of species breeding on oak-dominated reforestation # 10 years old. Agelaius phoeniceus (Red-winged Blackbird) and Colinus virginianus (Northern Bobwhite) characterized cottonwood reforestation # 4 years old, whereas 14 species of shrub-scrub birds (e.g., Passerina cyanea [Indigo Bunting]) and early-successional forest birds (e.g., Vireo gilvus [Warbling Vireo]) typified cottonwood reforestation 5 to 9 years after planting. Rates of daily nest survival did not differ between reforestation strategies. Nest parasitism increased markedly in older cottonwood stands, but was overwhelmed by predation as a cause of nest failure. Based on Partners in Flight prioritization scores and territory densities, the value of cottonwood reforestation for avian conservation was significantly greater than that of oak reforestation during their first 10 years. Because of benefits conferred on breeding birds, we recommend reforestation of bottomland hardwoods include a high proportion of fast-growing, early successional species such as cottonwood.

  3. Electron bunch acceleration in an inverse free-electron laser with a helical magnetic wiggler and axial guide field

    International Nuclear Information System (INIS)

    Electron bunch acceleration by a laser pulse having Gaussian radial and temporal profiles of intensity has been studied numerically in a static helical magnetic wiggler in vacuum. The main electron bunch parameters for simulations are 10 MeV initial energy with 0.1% longitudinal energy spread, 1 mm mrad rms transverse emittance, and 3x1012 cm-3 density. It is shown that the radial Gaussian profile can decrease the acceleration gradient compared with that of the plane-wave approximation due to the reduction of electron-pulse interaction area. In order to collimate electron bunch and overcome the decreasing of the acceleration gradient, an external axial magnetic field is used. The importance of the electron initial phase with respect to laser pulse is considered, and some appropriate values are found. Finally, acceleration of a femtosecond (fs) microbunch with an optimum appropriate initial phase is considered, which leads to a nearly monoenergetic microbunch and an acceleration gradient of about ≅0.2 GeV/m

  4. Fossil avian eggshell preserves ancient DNA

    DEFF Research Database (Denmark)

    Oskam, Charlotte L; Haile, James; McLay, Emma;

    2010-01-01

    Owing to exceptional biomolecule preservation, fossil avian eggshell has been used extensively in geochronology and palaeodietary studies. Here, we show, to our knowledge, for the first time that fossil eggshell is a previously unrecognized source of ancient DNA (aDNA). We describe the successful...

  5. Website for avian flu information and bioinformatics

    Institute of Scientific and Technical Information of China (English)

    GAO; George; Fu

    2009-01-01

    Highly pathogenic influenza A virus H5N1 has spread out worldwide and raised the public concerns. This increased the output of influenza virus sequence data as well as the research publication and other reports. In order to fight against H5N1 avian flu in a comprehensive way, we designed and started to set up the Website for Avian Flu Information (http://www.avian-flu.info) from 2004. Other than the influenza virus database available, the website is aiming to integrate diversified information for both researchers and the public. From 2004 to 2009, we collected information from all aspects, i.e. reports of outbreaks, scientific publications and editorials, policies for prevention, medicines and vaccines, clinic and diagnosis. Except for publications, all information is in Chinese. Till April 15, 2009, the cumulative news entries had been over 2000 and research papers were approaching 5000. By using the curated data from Influenza Virus Resource, we have set up an influenza virus sequence database and a bioinformatic platform, providing the basic functions for the sequence analysis of influenza virus. We will focus on the collection of experimental data and results as well as the integration of the data from the geological information system and avian influenza epidemiology.

  6. Website for avian flu information and bioinformatics

    Institute of Scientific and Technical Information of China (English)

    LIU Di; LIU Quan-He; WU Lin-Huan; LIU Bin; WU Jun; LAO Yi-Mei; LI Xiao-Jing; GAO George Fu; MA Jun-Cai

    2009-01-01

    Highly pathogenic influenza A virus H5N1 has spread out worldwide and raised the public concerns. This increased the output of influenza virus sequence data as well as the research publication and other reports. In order to fight against H5N1 avian flu in a comprehensive way, we designed and started to set up the Website for Avian Flu Information (http://www.avian-flu.info) from 2004. Other than the influenza virus database available, the website is aiming to integrate diversified information for both researchers and the public. From 2004 to 2009, we collected information from all aspects, i.e. reports of outbreaks, scientific publications and editorials, policies for prevention, medicines and vaccines, clinic and diagnosis. Except for publications, all information is in Chinese. Till April 15, 2009, the cumulative news entries had been over 2000 and research papers were approaching 5000. By using the curated data from Influenza Virus Resource, we have set up an influenza virus sequence database and a bioin-formatic platform, providing the basic functions for the sequence analysis of influenza virus. We will focus on the collection of experimental data and results as well as the integration of the data from the geological information system and avian influenza epidemiology.

  7. Avian Disease & Oncology Lab (ADOL) Research Update

    Science.gov (United States)

    Employing Genomics, Epigenetics, and Immunogenetics to Control Diseases Induced by Avian Tumor Viruses - Gene expression is a major factor accounting for phenotypic variation. Taking advantage of allele-specific expression (ASE) screens, we found the use of genetic markers was superior to traditiona...

  8. Measuring Steroid Hormones in Avian Eggs

    NARCIS (Netherlands)

    Engelhardt, Nikolaus von; Groothuis, Ton G.G.

    2005-01-01

    Avian eggs contain substantial levels of various hormones of maternal origin and have recently received a lot of interest, mainly from behavioral ecologists. These studies strongly depend on the measurement of egg hormone levels, but the method of measuring these levels has received little attention

  9. Avian pox in Magellanic Penguins (Spheniscus magellanicus).

    Science.gov (United States)

    Kane, Olivia J; Uhart, Marcela M; Rago, Virginia; Pereda, Ariel J; Smith, Jeffrey R; Van Buren, Amy; Clark, J Alan; Boersma, P Dee

    2012-07-01

    Avian pox is an enveloped double-stranded DNA virus that is mechanically transmitted via arthropod vectors or mucosal membrane contact with infectious particles or birds. Magellanic Penguins (Spheniscus magellanicus) from two colonies (Punta Tombo and Cabo Dos Bahías) in Argentina showed sporadic, nonepidemic signs of avian pox during five and two of 29 breeding seasons (1982-2010), respectively. In Magellanic Penguins, avian pox expresses externally as wart-like lesions around the beak, flippers, cloaca, feet, and eyes. Fleas (Parapsyllus longicornis) are the most likely arthropod vectors at these colonies. Three chicks with cutaneous pox-like lesions were positive for Avipoxvirus and revealed phylogenetic proximity with an Avipoxvirus found in Black-browed Albatross (Thalassarche melanophrys) from the Falkland Islands in 1987. This proximity suggests a long-term circulation of seabird Avipoxviruses in the southwest Atlantic. Avian pox outbreaks in these colonies primarily affected chicks, often resulted in death, and were not associated with handling, rainfall, or temperature. PMID:22740548

  10. Avian Influenza Risk Perception, Europe and Asia

    OpenAIRE

    de Zwart, Onno; Veldhuijzen, Irene K; Elam, Gillian; Aro, Arja R; Abraham, Thomas; Bishop, George D.; Richardus, Jan Hendrik; Brug, Johannes

    2007-01-01

    During autumn 2005, we conducted 3,436 interviews in European and Asian countries. We found risk perceptions of avian influenza to be at an intermediate level and beliefs of efficacy to be slightly lower. Risk perceptions were higher in Asia than Europe; efficacy beliefs were lower in Europe than Asia.

  11. Avian Influenza Outbreaks in Chickens, Bangladesh

    OpenAIRE

    Paritosh K Biswas; Christensen, Jens P.; Ahmed, Syed S.U.; Barua, Himel; Das, Ashutosh; Rahman, Mohammed H.; Giasuddin, Mohammad; Hannan, Abu S. M. A.; Habib, Mohammad A.; Ahad, Abdul; Rahman, Abu S.M.S.; Faruque, Rayhan; Nitish C Debnath

    2008-01-01

    To determine the epidemiology of outbreaks of avian influenza A virus (subtypes H5N1, H9N2) in chickens in Bangladesh, we conducted surveys and examined virus isolates. The outbreak began in backyard chickens. Probable sources of infection included egg trays and vehicles from local live bird markets and larger live bird markets.

  12. Serological diagnosis of avian influenza in poultry

    DEFF Research Database (Denmark)

    Comin, Arianna; Toft, Nils; Stegeman, Arjan;

    2013-01-01

    Background The serological diagnosis of avian influenza (AI) can be performed using different methods, yet the haemagglutination inhibition (HI) test is considered the gold standard' for AI antibody subtyping. Although alternative diagnostic assays have been developed, in most cases, their accuracy...

  13. Evolutionary dynamics of human and avian metapneumoviruses

    NARCIS (Netherlands)

    M.T. de Graaf (Marieke); A.D.M.E. Osterhaus (Ab); R.A.M. Fouchier (Ron); E.C. Holmes (Edward)

    2008-01-01

    textabstractHuman (HMPV) and avian (AMPV) metapneumoviruses are closely related viruses that cause respiratory tract illnesses in humans and birds, respectively. Although HMPV was first discovered in 2001, retrospective studies have shown that HMPV has been circulating in humans for at least 50 year

  14. Are we ready for the avian flu?

    Science.gov (United States)

    Huff, Charlotte

    2006-01-01

    It may be tempting to dismiss headlines about a potential avian flu pandemic as "the sky is falling" sensationalism, but experts continue to warn that the disease is likely to show up here in the not-too-distant future. What must hospitals do to prepare for a sudden influx of patients and other huge demands such a crisis would create? PMID:16485802

  15. Experimental induced avian E. coli salpingitis

    DEFF Research Database (Denmark)

    Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth;

    2016-01-01

    manifestations or from the cloacae of a healthy chicken. The virulence potential of the strains were evaluated in an avian experimental model for ascending infections, and experiments were conducted in both layers and broiler breeders. The clinical outcome of infection was highly depending on the challenge...

  16. CCNA Wireless Study Guide

    CERN Document Server

    Lammle, Todd

    2010-01-01

    A complete guide to the CCNA Wireless exam by leading networking authority Todd Lammle. The CCNA Wireless certification is the most respected entry-level certification in this rapidly growing field. Todd Lammle is the undisputed authority on networking, and this book focuses exclusively on the skills covered in this Cisco certification exam. The CCNA Wireless Study Guide joins the popular Sybex study guide family and helps network administrators advance their careers with a highly desirable certification.: The CCNA Wireless certification is the most respected entry-level wireless certification

  17. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  18. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    International Nuclear Information System (INIS)

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  19. Field-trip guide to the geology of the Lexington Reservoir and Loma Prieta areas in the Santa Cruz Mountains, Santa Clara and Santa Cruz counties, California

    Science.gov (United States)

    Stoffer, Philip W.; Messina, Paula

    2002-01-01

    This guide contains a road log and five stop descriptions for a field trip in the southern Santa Cruz Mountains. The trip officially begins at the boat dock parking area on Alma Bridge Road near the dam of Lexington Reservoir. Stop 1 involves a walk up the Limekiln Trail to examine a large landslide in serpentinite that frequently takes out the trail. Stop 2 is at Miller Point picnic area along the shore of the reservoir where exposures of massive, fractured graywacke sandstone are capped with terrace gravel deposits. Stop 3 is along Highland Way in the Santa Cruz Mountains where large landslides have occasionally force the closure of the road. Stop 4A-C are several closely spaced outcrop areas along Loma Prieta Avenue and Summit-Mt. Madonna Road in the Loma Prieta summit area. A walk to scenic vista points provide opportunity to discuss the evolution of regional landscape along the crest of the Sierra Azul. In addition, a variety of rock types are exposed in the Stop 4 area along a series of road cuts, including Cretaceous age conglomerate, turbidites (consisting of interbedded sandstone and shale), and fossiliferous mudstone. Stop 5 involves returning to the boat dock parking area to examine geology and the placement of the Lexington Dam in the Los Gatos Creek canyon.

  20. Science for avian conservation: priorities for the new millennium

    Science.gov (United States)

    Ruth, J.M.; Petit, D.R.; Sauer, J.R.; Samuel, M.D.; Johnson, F.A.; Fornwall, M.D.; Korschgen, C.E.; Bennett, J.P.

    2003-01-01

    together 51 scientists from USGS, as well as scientists and conservationists from other agencies and organizations actively participating in NABCI. As the lead federal agency involved in bird conservation research, USGS has a clear legislative mandate to provide scientific information upon which future management plans and actions will be built. This article summarizes key issues and recommendations that arose from that workshop. The principal goal of the workshop was to guide USGS in defining its role, assessing capabilities, and directing future agency planning in support of bird conservation. A major component was to identify key areas of research needed in this new era of bird conservation science. Although tailored to the mission of USGS, workshop recommendations visualize a bold direction for future avian conservation science in which research and monitoring work in tandem with management to increase our understanding of avian populations and the processes that affect them. The USGS is a science agency whose role is to provide objective scientific information to management agencies and therefore is not directly involved in high-level resource policy-making or on-the-ground management decision making. Nevertheless, it is important to note that effective policy decision making must integrate the best available science with political and economic realities to achieve successful avian conservationa??an important subject acknowledged in the workshop, but largely beyond its scope of discussion. Williams (2003) questions regarding how scientific information can be effectively communicated to decision makers and incorporated into natural resource policy. Without an aggressive vision and the willingness of researchers, managers, and policy makers to implement it, conservation of North American birds is likely to proceed without the full benefit of scientific investigation. These recommendations represent the principal conclusions drawn by workshop participants and d

  1. Mechanisms of transmission and spread of H5N1 high pathogenicity avian influenza virus in birds and mammals

    Science.gov (United States)

    The Eurasian-African H5N1 high pathogenicity avian influenza (HPAI) virus has crossed multiple species barriers to infect poultry, captive and wild birds, carnivorous mammals and humans. The specific transmission mechanisms are unclear in most cases, but experimental studies and field data sug...

  2. Draft Genome Sequences of Two Avian Pathogenic Escherichia coli Strains of Clinical Importance, E44 and E51.

    Science.gov (United States)

    Ronco, Troels; Stegger, Marc; Andersen, Paal S; Pedersen, Karl; Li, Lili; Thøfner, Ida C N; Olsen, Rikke H

    2016-01-01

    Avian pathogenic Escherichia coli strains have remarkable impacts on animal welfare and the production economy in the poultry industry worldwide. Here, we present the draft genomes of two isolates from chickens (E44 and E51) obtained from field outbreaks and subsequently investigated for their potential for use in autogenous vaccines for broiler breeders.

  3. A Robust New Method for Analzing Community Change and an Example using 83 years of Avian Response to Forest Succession

    Science.gov (United States)

    This manuscript describes a novel statistical analysis technique developed by the authors for use in combining survey data carried out under different field protocols. We apply the technique to 83 years of survey data on avian songbird populations in northern lower Michigan to de...

  4. Mathematics Curriculum Guide for Spanish-Speaking Students, Levels E, F. Field Test. Working Draft = Guia didactica de matematicas, Niveles E, F. Edicion Experimental.

    Science.gov (United States)

    Chicago Board of Education, IL. Dept. of Curriculum.

    The curriculum guide for mathematics instruction in the bilingual education program of the Chicago public schools is designed to assist teachers in the instruction of limited-English-speaking students in their native language. The guide outlines, for each of two levels, lessons on absolute and relative values of numbers, whole number operations,…

  5. Analyses of Temperature Field and Deflection of Steam Turbine IP Inlet Flow Guide%汽轮机中压进汽导流环温度场及变形分析

    Institute of Scientific and Technical Information of China (English)

    王林

    2014-01-01

    IP inlet flow guide is one of the key components in steam turbine,analyses of temperature field and deflection are important when flow guide of steam turbine is designed.Aim at a 600MW sub-critical steam turbine flow guide,a finite element model is developed,methods for calculating the heat transfer coefficients of flow guide surfaces different regions are described,the finite element thermal and structural analyses are performed on the flow guide.Detailed temperature and deflection distributions are determined during the steady operating conditions.The results show that radial temperature gradient is principal,radial deflection of flow guide foot is 1.611 3mm,radial deflection of flow guide with seal is 2.063 6 mm.The used analytic methods can be applied for temperature field and deflection analyses of sub-critical,supercritical and ultra-supercritical steam turbine flow guide,a basis for the bolting analysis and the cooling structural design of steam turbine flow guide is provided.%中压进汽导流环是汽轮机中的关键部件,在设计过程中必须分析其温度场及变形。针对某亚临界600MW汽轮机导流环,建立了有限元模型,介绍了导流环表面不同区域的传热系数计算方法,用有限元法分析了导流环的温度场和变形,得出了在稳态运行工况的详细温度和变形分布。结果表明,导流环温度梯度以径向为主,导流环的最下部径向变形为1.6113mm,导流环安装汽封处径向变形为2.0636mm。所采用的分析方法可以用于分析亚临界、超临界和超超临界汽轮机导流环的温度场和变形,为导流环螺栓分析和冷却结构设计打下基础。

  6. Morphometric Analysis of the Sternum in Avian Species

    OpenAIRE

    DÜZLER, Ayhan; Özgel, Özcan; DURSUN, Nejdet

    2006-01-01

    The anatomy of the sternum in avian species differs according to their movement and particularly flight capability, as well as species and habitat. Various studies aimed at the examination and measurement of the sternum in avian species have been carried out. However, to the authors' knowledge, no study on the correlation between sternal measurements and movement style has been published previously. In this study, the sternums of certain avian species including the red falcon (Buteo rufi...

  7. Multiple Control Strategies for Prevention of Avian Influenza Pandemic

    OpenAIRE

    Roman Ullah; Gul Zaman; Saeed Islam

    2014-01-01

    We present the prevention of avian influenza pandemic by adjusting multiple control functions in the human-to-human transmittable avian influenza model. First we show the existence of the optimal control problem; then by using both analytical and numerical techniques, we investigate the cost-effective control effects for the prevention of transmission of disease. To do this, we use three control functions, the effort to reduce the number of contacts with human infected with mutant avian influ...

  8. Avian influenza infections in birds – a moving target

    OpenAIRE

    Capua, Ilaria; Alexander, Dennis J.

    2006-01-01

    Avian influenza (AI) is a complex infection of birds, of which the ecology and epidemiology have undergone substantial changes over the last decade. Avian influenza viruses infecting poultry can be divided into two groups. The very virulent viruses cause highly pathogenic avian influenza (HPAI), with flock mortality as high as 100%. These viruses have been restricted to subtypes H5 and H7, although not all H5 and H7 viruses cause HPAI. All other viruses cause a milder, primarily respiratory, ...

  9. Walkthrough screening evaluation field guide

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) has a large inventory of existing facilities. Many of these facilities were not designed and constructed to current natural phenomena hazard (NPH) criteria. The NPH events include earthquakes, extreme winds and tornadoes, and floods. DOE Order 5480.28 establishes policy and requirements for NPH mitigation for DOE facilities. DOE is conducting a multiyear project to develop evaluation guidelines for assessing the condition and determining the need for upgrades at DOE facilities. One element of the NPH evaluation guidelines' development involves the existing systems and components at DOE facilities. This effort is described in detail in a cited reference. In the interim period prior to availability of the final guidelines, DOE facilities are encouraged to implement an NPH walk through screening evaluation process by which systems and components that need attention can be rapidly identified. Guidelines for conducting the walk through screening evaluations are contained herein. The result of the NPH walk through screening evaluation should be a prioritized list of systems and components that need further action. Simple and inexpensive fixes for items identified in the walk through as marginal or inadequate should be implemented without further study. By implementing an NPH walk through screening evaluation, DOE facilities may realize significant reduction in risk from NPH in the short term

  10. Avian influenza virus and free-ranging wild birds

    Science.gov (United States)

    Dierauf, Leslie A.; Karesh, W.B.; Ip, Hon S.; Gilardi, K.V.; Fischer, John R.

    2006-01-01

    Recent media and news reports and other information implicate wild birds in the spread of highly pathogenic avian influenza in Asia and Eastern Europe. Although there is little information concerning highly pathogenic avian influenza viruses in wild birds, scientists have amassed a large amount of data on low-pathogenicity avian influenza viruses during decades of research with wild birds. This knowledge can provide sound guidance to veterinarians, public health professionals, the general public, government agencies, and other entities with concerns about avian influenza.

  11. Avian use of Norris Hill Wind Resource Area, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Harmata, A.; Podruzny, K.; Zelenak, J. [Montana State Univ., Bozeman, MT (United States). Biology Dept.

    1998-07-01

    This document presents results of a study of avian use and mortality in and near a proposed wind resource area in southwestern Montana. Data collected in autumn 1995 through summer 1996 represented preconstruction condition; it was compiled, analyzed, and presented in a format such that comparison with post-construction data would be possible. The primary emphasis of the study was recording avian migration in and near the wind resource area using state-of-the-art marine surveillance radar. Avian use and mortality were investigated during the breeding season by employing traditional avian sampling methods, radiotelemetry, radar, and direct visual observation. 61 figs., 34 tabs.

  12. Seasonal change in the avian hippocampus.

    Science.gov (United States)

    Sherry, David F; MacDougall-Shackleton, Scott A

    2015-04-01

    The hippocampus plays an important role in cognitive processes, including memory and spatial orientation, in birds. The hippocampus undergoes seasonal change in food-storing birds and brood parasites, there are changes in the hippocampus during breeding, and further changes occur in some species in association with migration. In food-storing birds, seasonal change in the hippocampus occurs in fall and winter when the cognitively demanding behaviour of caching and retrieving food occurs. The timing of annual change in the hippocampus of food-storing birds is quite variable, however, and appears not to be under photoperiod control. A variety of factors, including cognitive performance, exercise, and stress may all influence seasonal change in the avian hippocampus. The causal processes underlying seasonal change in the avian hippocampus have not been extensively examined and the more fully described hormonal influences on the mammalian hippocampus may provide hypotheses for investigating the control of hippocampal seasonality in birds.

  13. Applications of thermal imaging in avian science

    OpenAIRE

    McCafferty, D. J.

    2013-01-01

    Thermal imaging, or infrared thermography, has been used in avian science since the 1960s. More than 30 species of birds, ranging in size from passerines to ratites, have been studied using this technology. The main strength of this technique is that it is a non-invasive and non-contact method of measuring surface temperature. Its limitations and measurement errors are well understood and suitable protocols have been developed for a variety of experimental settings. Thermal imaging has been u...

  14. Avian influenza and poultry workers, Peru, 2006

    OpenAIRE

    Ortiz, Ernesto J.; Tadeusz J Kochel; Capuano, Ana W; Setterquist, Sharon F.; Gray, Gregory C.

    2007-01-01

    Background  Currently numerous countries in Asia, Africa and Europe are encountering highly pathogenic avian influenza (AI) infections in poultry and humans. In the Americas, home of the world’s largest poultry exporters, contingency plans are being developed and evaluated in preparation for the arrival of these viral strains. Objectives  With this cross‐sectional study, to our knowledge the first in its kind in Central or South America, we sought to learn whether Peruvian poultry workers had...

  15. Prevalence of avian influenza and host ecology

    OpenAIRE

    Garamszegi, László Zsolt; Møller, Anders Pape

    2007-01-01

    Waterfowl and shorebirds are common reservoirs of the low pathogenic subtypes of avian influenza (LPAI), which are easily transmitted to poultry and become highly pathogenic. As the risk of virus transmission depends on the prevalence of LPAI in host-reservoir systems, there is an urgent need for understanding how host ecology, life history and behaviour can affect virus prevalence in the wild. To test for the most important ecological correlates of LPAI virus prevalence at the interspecific ...

  16. Aerosolized avian influenza virus by laboratory manipulations

    OpenAIRE

    Li Zhiping; Li Jinsong; Zhang Yandong; Li Lin; Ma Limin; Li Dan; Gao Feng; Xia Zhiping

    2012-01-01

    Abstract Background Avian H5N1 influenza viruses present a challenge in the laboratory environment, as they are difficult to collect from the air due to their small size and relatively low concentration. In an effort to generate effective methods of H5N1 air removal and ensure the safety of laboratory personnel, this study was designed to investigate the characteristics of aerosolized H5N1 produced by laboratory manipulations during research studies. Results Normal laboratory procedures used ...

  17. Control of Avian Influenza in Poultry

    OpenAIRE

    Capua, Ilaria; Marangon, Stefano

    2006-01-01

    Avian influenza, listed by the World Organization for Animal Health (OIE), has become a disease of great importance for animal and human health. Several aspects of the disease lack scientific information, which has hampered the management of some recent crises. Millions of animals have died, and concern is growing over the loss of human lives and management of the pandemic potential. On the basis of data generated in recent outbreaks and in light of new OIE regulations and maintenance of anim...

  18. Avian influenza: The tip of the iceberg

    OpenAIRE

    Balkhy Hanan

    2008-01-01

    For some years now, we have been living with the fear of an impending pandemic of avian influenza (AI). Despite the recognition, in 1996, of the global threat posed by the highly pathogenic H5N1 influenza virus found in farmed geese in Guangdong Province, China, planning for the anticipated epidemic remains woefully inadequate; this is especially true in developing countries such as Saudi Arabia. These deficiencies became obvious in 1997, with the outbreak of AI in the live animal markets in...

  19. Avian influenza: Myth or mass murder?

    OpenAIRE

    Carol Louie

    2005-01-01

    The purpose of the present article was to determine whether avian influenza (AI) is capable of causing a pandemic. Using research from a variety of medical journals, books and texts, the present paper evaluates the probability of the AI virus becoming sufficiently virulent to pose a global threat. Previous influenza A pandemics from the past century are reviewed, focusing on the mortality rate and the qualities of the virus that distinguish it from other viruses. Each of the influenza A virus...

  20. Evaluation of Antiviral Compounds Against Avian Influenza

    OpenAIRE

    Call, Evan W.

    1991-01-01

    Tests in vitro for antiviral activity against avian influenza viruses, A/Turkey/Sanpete/85 (H6N8) and A/Turkey/Sanpete/86 (H10N9), isolated in Sanpete County, Utah, utilized known antiviral agents, amantadine•HCl (adamantanamine hydrochloride) and ribavirin (1-β-D ribofuranosyl-1,2,4-triazole-3-carboxamide). The testing involved evaluation of seven drug concentrations. Maximum tolerated dose, minimum inhibitory concentration and therapeutic indexes were determined for each drug used. Both dru...

  1. Avian influenza: genetic evolution under vaccination pressure

    OpenAIRE

    Nava Gerardo M; Lucio Eduardo; Rodríguez-Ropón Andrea; Méndez Sara T; Vázquez Lourdes; Escorcia Magdalena

    2008-01-01

    Abstract Antigenic drift of avian influenza viruses (AIVs) has been observed in chickens after extended vaccination program, similar to those observed with human influenza viruses. To evaluate the evolutionary properties of endemic AIV under high vaccination pressure (around 2 billion doses used in the last 12 years), we performed a pilot phylogenic analysis of the hemagglutinin (HA) gene of AIVs isolated from 1994 to 2006. This study demonstrates that Mexican low pathogenicity (LP) H5N2-AIVs...

  2. Avian Influenza: Mixed Infections and Missing Viruses

    OpenAIRE

    Wentworth, David E.; Dugan, Vivien G.; Xudong Lin; Seth Schobel; Magdalena Plancarte; Kelly, Terra R.; Lindsay, LeAnn L.; Boyce, Walter M.

    2013-01-01

    A high prevalence and diversity of avian influenza (AI) viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA) gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined ...

  3. Avian cytokines in health and disease

    Directory of Open Access Journals (Sweden)

    Wigley P

    2003-01-01

    Full Text Available Cytokines are proteins secreted by cells that play an important role in the activation and regulation of other cells and tissues during inflammation and immune responses. Although well described in several mammalian species, the role of cytokines and other related proteins is poorly understood in avian species. Recent advances in avian genetics and immunology have begun to allow the exploration of cytokines in health and disease. Cytokines may be classified in a number of ways, but may be conveniently arranged into four broad groups on the basis of their function. Proinflammatory cytokines such as interleukin-6 and interleukin-1beta play a role in mediating inflammation during disease or injury. Th1 cytokines, including interleukin-12 and interferon-gamma, are involved in the induction of cell-mediated immunity, whereas Th2 cytokines such as interleukin-4 are involved in the induction of humoral immunity. The final group Th3 or Tr cytokines play a role in regulation of immunity. The role of various cytokines in infectious and non-infectious diseases of chickens and turkeys is now being investigated. Although there are only a few reliable ELISAs or bioassays developed for avian cytokines, the use of molecular techniques, and in particular quantitative RT-PCR (Taqman has allowed investigation of cytokine responses in a number of diseases including salmonellosis, coccidiosis and autoimmune thyroiditis. In addition the use of recombinant cytokines as therapeutic agents or as vaccine adjuvants is now being explored.

  4. Toward a Rapid Synthesis of Field and Desktop Data for Classifying Streams in the Pacific Northwest: Guiding the Sampling and Management of Salmonid Habitat

    Science.gov (United States)

    Kasprak, A.; Wheaton, J. M.; Bouwes, N.; Weber, N. P.; Trahan, N. C.; Jordan, C. E.

    2012-12-01

    River managers often seek to understand habitat availability and quality for riverine organisms within the physical template provided by their landscape. Yet the large amount of natural heterogeneity in landscapes gives rise to stream systems which are highly variable over small spatial scales, potentially complicating site selection for surveying aquatic habitat while simultaneously making a simple, wide-reaching management strategy elusive. This is particularly true in the rugged John Day River Basin of northern Oregon, where efforts as part of the Columbia Habitat Monitoring Program to conduct site-based surveys of physical habitat for endangered steelhead salmon (Oncorhynchus mykiss) are underway. As a complete understanding of the type and distribution of habitat available to these fish would require visits to all streams in the basin (impractical due to its large size), here we develop an approach for classifying channel types which combines remote desktop GIS analyses with rapid field-based stream and landscape surveys. At the core of this method, we build off of the River Styles Framework, an open-ended and process-based approach for classifying streams and informing management decisions. This framework is combined with on-the-ground fluvial audits, which aim to quickly and continuously map sediment dynamics and channel behavior along selected channels. Validation of this classification method is completed by on-the-ground stream surveys using a digital iPad platform and by rapid small aircraft overflights to confirm or refine predictions. We further compare this method with existing channel classification approaches for the region (e.g. Beechie, Montgomery and Buffington). The results of this study will help guide both the refinement of site stratification and selection for salmonid habitat monitoring within the basin, and will be vital in designing and prioritizing restoration and management strategies tailored to the distribution of river styles found

  5. Guided labworks

    DEFF Research Database (Denmark)

    Jacobsen, Lærke Bang

    For the last 40 years physics education research has shown poor learning outcomes of guided labs. Still this is found to be a very used teaching method in the upper secodary schools. This study explains the teacher's choice of guided labs throught the concept of redesign as obstacle dislodgement...

  6. Base-Matics. Teacher's Guide.

    Science.gov (United States)

    Frame, Laurence

    This teacher's guide contains the following sections: Teacher Objectives; Student Objectives; Teacher Aid Suggestions; Objectives Overview; Teacher's Guide; Drawing Page; American League Team Addresses; National League Team Addresses; Student Activities; Baseball Field Dimensions; Age Problems; Statistics from a Newspaper; Time Problems; Height…

  7. 适用于小视场星敏感器的导航星表构建方法%Guide star selection method for star tracker with thin field of view

    Institute of Scientific and Technical Information of China (English)

    崔祥祥; 王宏力; 陆敬辉; 乔兴; 邓长智; 张勇; 赵爱罡

    2015-01-01

    Guide star selection is a crucial part of star tracker design. For thin field-of-view star tracker, guide star catalog "holes" are common as stars are not evenly distributed. To optimize the guide star selection for star tracker with thin field of view, the selection method based on spherical spiral points was modified. Building a new guide star catalog by increasing the number and changing the positions of spherical spiral points, which was usually adopted, was abandoned. Some new stars which can effectively decrease guide star catalog "holes" into the guide star catalog were proposed. The weights to measure stars’ ability of decreasing guide star catalog "holes" were constructed and the adding star process was carried out on the order of the weights descending. And the new star added into guide star catalog was required far away from the guide stars to keep the guide stars even. Simulations expressed that the modified method got less and evener guide stars than the original method with similar guide star catalog"holes", which shows the superiority of the modified method.%导航星表构建是星敏感器设计阶段的重要工作。对于小视场,受限于恒星分布规律,易出现导航星表“空洞”问题。为解决小视场条件下均匀完备导航星表构建问题,对基于球面螺旋基准点的导航星表构建方法进行了改进:摒弃了原方法通过改变球面螺旋基准点数量和位置重新构建导航星表的思路,转而通过增选部分恒星来达到减少星表“空洞”的目的。设立了描述恒星消除星表“空洞”能力的权值,并以该权值递减顺序开展恒星增选;同时,设计了增选恒星距离阈值条件以保持增选后导航星表的均匀性。仿真表明,在4º圆形视场条件下,相对于原方法,文中方法得到的导航星表,总星数减少708颗,均匀性指标提高约44%,而星表“空洞”变化较小,显示了较好的性能。

  8. Teacher's Guide for Earthworms.

    Science.gov (United States)

    Bruno, Merle S.; And Others

    This teacher's guide on earthworms includes four major sections: (1) introduction, (2) caring for earthworms in the classroom, (3) classroom activities, and (4) the appendix. The introduction includes information concerning grade level, scheduling, materials, obtaining earthworms, field study, classroom clean-up, and records. Caring for earthworms…

  9. Environmental Horticulture Program Guide.

    Science.gov (United States)

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide contains the standard environmental horticulture curriculum for technical institutes in Georgia. The curriculum encompasses the minimum competencies required for entry-level workers in the environmental horticulture field. The general information section contains the following: purpose and objectives; program description,…

  10. HBR guides

    CERN Document Server

    Duarte, Nancy; Dillon, Karen

    2015-01-01

    Master your most pressing professional challenges with this seven-volume set that collects the smartest best practices from leading experts all in one place. "HBR Guide to Better Business Writing" and "HBR Guide to Persuasive Presentations" help you perfect your communication skills; "HBR Guide to Managing Up and Across" and "HBR Guide to Office Politics" show you how to build the best professional relationships; "HBR Guide to Finance Basics for Managers" is the one book you'll ever need to teach you about the numbers; "HBR Guide to Project Management" addresses tough questions such as how to manage stakeholder expectations and how to manage uncertainty in a complex project; and "HBR Guide to Getting the Right Work Done" goes beyond basic productivity tips to teach you how to prioritize and focus on your work. This specially priced set of the most popular books in the series makes a perfect gift for aspiring leaders looking for trusted advice. Arm yourself with the advice you need to succeed on the job, from ...

  11. Ontogeny of avian thermoregulation from a neural point of view

    NARCIS (Netherlands)

    Baarendse, P.J.J.; Debonne, M.; Decuypere, M.P.; Kemp, B.; Brand, van den H.

    2007-01-01

    The ontogeny of thermoregulation differs among (avian) species, but in all species both neural and endocrinological processes are involved. In this review the neural processes in ontogeny of thermoregulation during the prenatal and early postnatal phase are discussed. Only in a few avian species (ch

  12. Avian Influenza Viruses in Water Birds, Africa 1

    OpenAIRE

    Gaidet, Nicolas; Dodman, Tim; Caron, Alexandre; Balança, Gilles; Desvaux, Stephanie; Goutard, Flavie; Cattoli, Giovanni; Lamarque, François; Hagemeijer, Ward; Monicat, François

    2007-01-01

    We report the first large-scale surveillance of avian influenza viruses in water birds conducted in Africa. This study shows evidence of avian influenza viruses in wild birds, both Eurasian and Afro-tropical species, in several major wetlands of Africa.

  13. Genetic differences between avian and human isolates of Candida dubliniensis.

    LENUS (Irish Health Repository)

    McManus, Brenda A

    2009-09-01

    When Candida dubliniensis isolates obtained from seabird excrement and from humans in Ireland were compared by using multilocus sequence typing, 13 of 14 avian isolates were genetically distinct from human isolates. The remaining avian isolate was indistinguishable from a human isolate, suggesting that transmission may occur between humans and birds.

  14. China's Cool Handling of Avian Flu

    Institute of Scientific and Technical Information of China (English)

    LIWUZHOU

    2004-01-01

    ON January 27, 2004,the China National Avian Flu Reference Lab confirmed that in Dingdang Town, Long'an County,Guangxi Zhuang Autonomous Region a duck had died of the highly pathogenic H5N1 avian influenza. In contrast to the SARS epidemic last year, this occurrence has been handled coolly and efficiently by the Chinese government and people in general.

  15. Molecular cloning and functional characterization of avian interleukin-19

    Science.gov (United States)

    The present study describes the cloning and functional characterization of avian interleukin (IL)-19, a cytokine that, in mammals, alters the balance of Th1 and Th2 cells in favor of the Th2 phenotype. The full-length avian IL-19 gene, located on chromosome 26, was amplified from LPS-stimulated chi...

  16. Avian magnetoreception model realized by coupling a magnetite-based mechanism with a radical-pair-based mechanism

    Institute of Scientific and Technical Information of China (English)

    Lü Yan; Song Tao

    2013-01-01

    Many animal species have been proven to use the geomagnetic field for their navigation,but the biophysical mechanism of magnetoreception has remained enigmatic.In this paper,we present a special biophysical model that consists of magnetite-based and radical-pair-based mechanisms for avian magnetoreception.The amplitude of the resultant magnetic field around the magnetic particles corresponds to the geomagnetic field direction and affects the yield of singlet/triplet state products in the radical-pair reactions.Therefore,in the proposed model,the singlet/triplet state product yields are related to the geomagnetic field information for orientational detection.The resultant magnetic fields corresponding to two materials with different magnetic properties are analyzed under different geomagnetic field directions.The results show that ferromagnetic particles in organisms can provide more significant changes in singlet state products than superparamagnetic particles,and the period of variation for the singlet state products with an included angle in the geomagnetic field is approximately 180° when the magnetic particles are ferromagnetic materials,consistent with the experimental results obtained from the avian magnetic compass.Further,the calculated results of the singlet state products in a reception plane show that the proposed model can explain the avian magnetoreception mechanism with an inclination compass.

  17. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    Science.gov (United States)

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  18. Infection of Avian Pox Virus in Oriental Turtle-Doves

    Directory of Open Access Journals (Sweden)

    Kyung-Yeon Eo1, Young-Hoan Kim2, Kwang-Hyun Cho3, Jong-Sik Jang4, Tae-Hwan Kim5, Dongmi Kwak5 and Oh-Deog Kwon5*

    2011-10-01

    Full Text Available Three Oriental Turtle-doves (Streptopelia orientalis exhibiting lethargy, dyspnea, poor physical condition, and poor flight endurance, were rescued and referred to the Animal Health Center, Seoul Zoo, Korea. The doves had wart-like lesions on the legs and head. All of them died the following day after arrival, with the exception of one that survived for 6 days. Diphtheritic membranes on the tongue and oral mucosa were apparent at necropsy. Avian pox virus infection was suspected based on the proliferative skin lesions and oral diphtheritic lesions. Infection of the avian pox virus was confirmed by PCR using primers specific to the 4b core protein gene of avian pox virus. All cases were diagnosed with avian pox virus infection. This is believed to be the first description on natural infection of avian pox in Oriental Turtle-doves in Korea.

  19. Avian influenza virus infection in people occupied in poultry fields in Guangzhou city%广州市禽类从业人群禽流感病毒感染特征分析

    Institute of Scientific and Technical Information of China (English)

    柳洋; 王鸣; 鲁恩洁; 王玉林; 狄飚; 李铁钢; 周勇; 杨丽莉; 许晓茵; 傅传喜

    2009-01-01

    目的 应用血清流行病学调查广州市禽类从业人群感染禽流感病毒H5N1、H9N2、H7N7的状况,分析其感染特征.方法 采集广州市与禽类接触相关的职业人群血清,包括农贸市场活禽零售与非禽类零售人群、企业化家禽养殖与农村家禽散养人群、活禽批发市场人群、野生鸟驯养人群、生猪屠宰人群以及一般人群,用血凝抑制试验、中和抗体试验检测H5、H9、H7 IgG抗体;使用logistic回归分析、χ~2检验分析感染率分布.结果 2881名调查对象中检测出4例H5抗体阳性(0.14%);146例H9抗体阳性(5.07%),其中以活禽零售人群H9感染率最高(14.96%),企业化家禽养殖人群为8.90%,活禽批发人群为6.69%,野生鸟驯养人群为3.75%,生猪养殖人群为2.40%,非禽类零售人群为2.21%,农村家禽散养人群为1.77%,一般人群为2.30%.而1926名禽类从业人群中H7抗体均为阴性.结论 人群中H5感染率较低,而H9感染率较高,未检测到H7感染;活禽零售、家禽批发、企业化家禽养殖等职业具有较高感染禽流感病毒的风险,其中以活禽零售感染风险最高,且接触家禽时间越长感染风险越高.%Objective To conduct serological investigation on H5N1/H9N2/H7N7 infection among people occupied in poultry fields. Methods Serum samples were collected from people working in live poultry and none-poultry retailing food markets, poultry wholesaling, large-scale poultry breading factories and in small-scale farms, wide birds breeding, swine slaughtering houses and from normal population. Antibodies of H5, H9 and H7 with hemagglutination inhibition and neutralization tests were tested and analyzed. Logistic regression and χ~2 test were used. Results Among 2881 samples, 4 were positive to H5-Ab(0.14%), 146 were positive to H9-Ab (5.07%) and the prevalence of H9 among people from live poultry retailing (14.96%) was the highest. Prevalence rates of H9 were as follows: 8.90% in people working in

  20. Medication Guide

    Science.gov (United States)

    ... Size Small Text Medium Text Large Text Contrast Dark on Light Light on Dark Donate Search Menu Donate What is Glaucoma? Care ... Low Vision Resources Medication Guide Resources on the Web » See All Articles Help the Cause Glaucoma affects ...

  1. Cost comparison of low-field (0.23 T) MRI-guided laser ablation and surgery in the treatment of osteoid osteoma

    Energy Technology Data Exchange (ETDEWEB)

    Ronkainen, J.; Blanco Sequeiros, R.; Tervonen, O. [Oulu University Hospital, Department of Radiology, P.O. Box 50, Oulu (Finland)

    2006-12-15

    The purpose of this study was to analyze the costs of magnetic resonance imaging (MRI)-guided laser ablation and to compare them with the costs of surgery in the treatment of osteoid osteoma. Seven patients with osteoid osteoma were treated with MRI-guided interstitial laser ablation during 1 year. The reference material consisted of six patients whose osteoid osteoma was treated surgically by either superficial or deep excision with metallic fixation. The costs were analyzed by using activity-based cost accounting. The mean cost of the MRI-guided laser ablation was 2,392 euros and of the excision of superficially located osteoid osteoma 1,807 euros. The cost of excision of deeply located osteoma with metallic fixation was considerably higher (4,996 euros). This was due to the higher material, personnel, and ward costs. The cost of MRI-guided laser ablation of osteoid osteoma was higher than the cost of surgical excision of a superficial osteoma but considerably lower than the cost of excision of a deeply located osteoma where metallic fixation was needed. When the number and mean cost of sick days or days of restricted weight bearing were also included, the cost of MRI-guided laser ablation was lower than the costs of either superficial or deep excision. (orig.)

  2. Molecular diagnostics of Avian influenza virus

    Directory of Open Access Journals (Sweden)

    Petrović Tamaš

    2006-01-01

    direct sequencing of the PCR product. The possibility of typization using molecular methods is based on the big difference at the amino acid and nucleotide levels between different HA subtypes (from 20- 74%, while the differences between strains of the same HA subtype are relatively small (0- 9%. The basic advantage in the detection and typization of influenza viruses using the RTPCR method is that it saves time. Namely, it can be performed directly from the samples taken in the field, and the result can be obtained within the same day, contrary to conventional methods that take 7 to 10 days. The obtained PCR product can also be sequenced immediately, which can provide an answer to the possible virulent potential of the isolate and its further spreading. The establishment of changes in the HA gene sequence can provide us with the information about the direction of the development of the genetic drift. The paper will describe in detail the possibilities for the implementation of molecular methods in diagnostics and typization, in fact, in the molecular epizootiology of avian influenza.

  3. Whole brain radiotherapy plus simultaneous in-field boost with image guided intensity-modulated radiotherapy for brain metastases of non-small cell lung cancer

    International Nuclear Information System (INIS)

    Whole brain radiotherapy (WBRT) plus sequential focal radiation boost is a commonly used therapeutic strategy for patients with brain metastases. However, recent reports on WBRT plus simultaneous in-field boost (SIB) also showed promising outcomes. The objective of present study is to retrospectively evaluate the efficacy and toxicities of WBRT plus SIB with image guided intensity-modulated radiotherapy (IG-IMRT) for inoperable brain metastases of NSCLC. Twenty-nine NSCLC patients with 87 inoperable brain metastases were included in this retrospective study. All patients received WBRT at a dose of 40 Gy/20 f, and SIB boost with IG-IMRT at a dose of 20 Gy/5 f concurrent with WBRT in the fourth week. Prior to each fraction of IG-IMRT boost, on-line positioning verification and correction were used to ensure that the set-up errors were within 2 mm by cone beam computed tomography in all patients. The one-year intracranial control rate, local brain failure rate, and distant brain failure rate were 62.9%, 13.8%, and 19.2%, respectively. The two-year intracranial control rate, local brain failure rate, and distant brain failure rate were 42.5%, 30.9%, and 36.4%, respectively. Both median intracranial progression-free survival and median survival were 10 months. Six-month, one-year, and two-year survival rates were 65.5%, 41.4%, and 13.8%, corresponding to 62.1%, 41.4%, and 10.3% of intracranial progression-free survival rates. Patients with Score Index for Radiosurgery in Brain Metastases (SIR) >5, number of intracranial lesions <3, and history of EGFR-TKI treatment had better survival. Three lesions (3.45%) demonstrated radiation necrosis after radiotherapy. Grades 2 and 3 cognitive impairment with grade 2 radiation leukoencephalopathy were observed in 4 (13.8%) and 4 (13.8%) patients. No dosimetric parameters were found to be associated with these late toxicities. Patients received EGFR-TKI treatment had higher incidence of grades 2–3 cognitive impairment with grade

  4. On the Electron Dynamics during Rapid Asymmetric Magnetic Island Coalescence: Insights on the Electrons Agyrotropy with the Presence of a Guide Field

    Science.gov (United States)

    Cazzola, Emanuele; Lapenta, Giovanni; Innocenti, Maria Elena; Goldman, Martin; Newman, David; Markidis, Stefano

    2016-04-01

    The work presents a fully kinetic analysis of the electrons dynamics during rapid island coalescence in asymmetric magnetic reconnection, especially focused on the comparison between the case with and with no initial guide field. Formation and growth of the islands are caused by an intentionally unstable initial configuration across the current sheet with the same asymmetric profiles as those traditionally proposed in the literature (e.g. Pritchett, 2008). Particular attentions is given to the different evolution of the presumed reconnection sites. Three main regions are eventually identified, named by X-, D- and M-regions, which describe, respectively, the regions featuring a traditional reconnection event, those showing an opposite behavior with respect to the former and the reconnection regions occurring between two magnetic islands (Cazzola et al., 2015). Further analysis is mainly addressed to evaluate both the electrons departure from the isotropic and gyrotropic behavior. Whether the first quantity has been clearly established and confirmed by observations, the latter has always appeared of difficult interpretation, and an ultimate accepted method on how to render it from PIC simulations still seems far to be achieved. In light of the upcoming data from the freshly launched MMS NASA mission, outcomes from some of the main techniques to spot agyrotropic regions are here compared to highligh the presence of possible relevant differences (Scudder and Daughton, 2008; Swisdak, 2015). References [1] P. Pritchett, "Collisionless magnetic reconnection in an asymmetric current sheet," Journal of Geophysical Research: Space Physics (1978-2012), vol. 113, no. A6, 2008. [2] E. Cazzola, M. E. Innocenti, S. Markidis, M. V. Goldman, D. L. Newman, and G. Lapenta, "On the electron dynamics during island coalescence in asymmetric magnetic reconnection," Physics of Plasmas (1994-present), vol. 22, no. 9, p. 092901, 2015. [3] J. Scudder and W. Daughton, "Illuminating electron

  5. Comparison of two treatment strategies for irradiation of regional lymph nodes in patients with breast cancer: Lymph flow guided portals versus standard radiation fields

    Science.gov (United States)

    Novikov, Sergey Nikolaevich; Kanaev, Sergey Vasilevich; Semiglazov, Vladimir Fedorovich; Jukova, Ludmila Alekseevna; Krzhivitckiy, Pavel Ivanovich

    2014-01-01

    Aim and Background Radiotherapy being an essential part of breast cancer treatment, we evaluate various radiotherapy strategies in patients with breast cancer. Materials and methods Lymph node (LN) scintigraphy was performed in 172 primary patients with BC. LN visualization started 30–360 min after intratumoral injection of 75–150 MBq of 99mTc-nanocolloids. Our standard recommendation for postoperative radiotherapy in patients with LN invasion by BC were as follows: for patients with external localization of tumour – breast + axillary (Ax) + sub-supraclavicular (SSCL) regions; with internal localization – all above + internal mammary nodes (IM). Proposed strategy of lymph flow guided radiotherapy is based on the assumption that only regions that contain ‘hot’ LNs must be included in a treatment volume. Results Among 110 patients with external localization of BC, Ax LNs were visualized in all cases and in 62 patients it was the only region with ‘hot’ LN. Twenty-three patients (20.9%) had drainage to Ax + SSCL, 12 (10.9%) – Ax + IM, 13 (11.8%) – Ax + SSCL + IM regions. After the visualization of lymph flow patterns, standard treatment volume was changed in 87/110 cases (79.1%): in 56.4%, reduced, in 22.7%, enlarged or changed. In 62 patients with tumours in internal quadrants, we revealed the following patterns of lymph-flow: only to the Ax region in 23 (37.1%); Ax + IM, 13 (21%); Ax + SSCL, 15 (24.2%); Ax + IM + ISSCL, 11 (17.7%) cases. After lymph-flow visualization, the standard irradiation volume was reduced in 53/62 (85.5%) cases. Conclusion Visualization of an individual lymph flow pattern from BC can be used for the optimization of standard fields used for irradiation of regional LNs. PMID:25535581

  6. Short-term effects of avian predation variation on population size and local survival of the multimammate rat, Mastomys natalensis (Rodentia, Muridae)

    DEFF Research Database (Denmark)

    Gulck, T. van; Stocks, R.; Verhagen, Ron;

    1998-01-01

    The influence of avian predation on population size and local survival of Mastomys natalensis rats in Tanzania was studied in a capture-recapture study over a six month period on experimental fields with decreased, controlled and increased predation pressure. Bird observations indicated...... was not true but this might be due to the small size of the experimental fields. Analysis of weekly collected raptor pellets, over a 15 month period, showed an overrepresentation of M. natalensis as prey and a strong positive correlation between the density of M. natalensis and the avian predation intensity....

  7. Quantum limit for avian magnetoreception: How sensitive can a chemical compass be?

    CERN Document Server

    Cai, Jianming; Plenio, Martin B

    2011-01-01

    The chemical compass model, based on radical pair reactions, is a fascinating idea to explain avian magnetoreception. At present, questions concerning the key ingredients responsible for the high sensitivity of a chemical compass and the possible role of quantum coherence and decoherence remain unsolved. Here, we investigate the optimized hyperfine coupling for a chemical compass in order to achieve the best magnetic field sensitivity. We demonstrate that its magnetic sensitivity limit can be further extended by simple quantum control and may benefit from additional decoherence. The present results also provide routes towards the design a biomimetic weak magnetic field sensor.

  8. Mapping and modelling of Angola's avian diversity

    OpenAIRE

    Monteiro, Miguel José Ascensão Freire Parada

    2014-01-01

    Mestrado em Gestão e Conservação de Recursos Naturais - Instituto Superior de Agronomia / Universidade de Évora Angola harbours one of the richest and most diverse avifaunas in Africa, due to its vast number of biomas and ecosystems. However, mainly due to the Portuguese Colonial war (1961-1974) and Angolan civil war (1974-2002), the country’s avian diversity and distribution is still poorly known. One way to increase the scientific knowledge of Angolan ornithology is by studyi...

  9. Avian artificial insemination and semen preservation

    Science.gov (United States)

    Gee, G.F.

    1983-01-01

    Summary: Artificial insemination is a practical propagation tool that has been successful with a variety of birds. Cooperative, massage, and electroejaculation and modifications of these three basic methods of semen collection are described for a variety of birds. Semen color and consistency and sperm number, moti!ity, and morphology, as discussed, are useful indicators of semen quality, but the most reliable test of semen quality is the production of fertile eggs. Successful cryogenic preservation of avian semen with DMSO or glycerol as the cryoprotectant has been possible. Although the methods for preservation require special equipment, use of frozen semen requires only simple insemination supplies

  10. Avian influenza risk perception, Hong Kong

    OpenAIRE

    Fielding, Richard; Lam, Wendy W.T.; Ho, Ella Y.Y.; Lam, Tai Hing; Hedley, Anthony J.; Leung, Gabriel M

    2005-01-01

    A telephone survey of 986 Hong Kong households determined exposure and risk perception of avian influenza from live chicken sales. Householders bought 38,370,000 live chickens; 11% touched them when buying, generating 4,220,000 exposures annually; 36% (95% confidence interval [CI] 33%–39%) perceived this as risky, 9% (7%–11%) estimated >50% likelihood of resultant sickness, whereas 46% (43%–49%) said friends worried about such sickness. Recent China travel (adjusted odds ratio 0.35; CI 0.13–0...

  11. Current genomic editing approaches in avian transgenesis.

    Science.gov (United States)

    Park, Tae Sub; Kang, Kyung Soo; Han, Jae Yong

    2013-09-01

    The chicken was domesticated from Red Jungle Fowl over 8000years ago and became one of the major food sources worldwide. At present, the poultry industry is one of the largest industrial animal stocks in the world, and its economic scale is expanding significantly with increasing consumption. Additionally, since Aristotle used chicken eggs as a model to provide remarkable insights into how life begins, chickens have been used as invaluable and powerful experimental materials for studying embryo development, immune systems, biomedical processes, and hormonal regulation. Combined with advancements in efficient transgenic technology, avian models have become even more important than would have been expected.

  12. Diversity and Distribution of Avian Fauna of Swat, Khyber Pakhtunkhwa, Pakistan

    Directory of Open Access Journals (Sweden)

    Amir Jan Pathan

    2014-01-01

    Full Text Available This survey was conducted from January 2013 to December 2013 to explore the avian fauna of Swat valley and to find out the major threats to the avian fauna of the area as it was neglected for years. Direct and indirect methods were used in the study by visiting the field and by interviewing the local peoples and hunters about the current and past status of the avian fauna of the area. During the current study direct and indirect methods were used. A total of 138 species were recorded belonging to 13 orders and 48 families. The order Passeriformes were recorded much in number that were 31 species. Most of the birds were migratory and few were resident. The fauna was very rich due to the flora of the area and also due to less hunting. Orders Anseriformes, Apodiformes, Charadriiformes, Columbiformes, Pelecaniformes, Phoenicopteriformes, and Psittaciformes were found migratory and orders Ciconiiformes, Coraciiformes, Galliformes, and Piciformes were found resident while some members of Gruiformes and Passeriformes were found migratory and some resident.

  13. The case for infrasound as the long-range map cue in avian navigation

    Science.gov (United States)

    Hagstrum, J.T.

    2007-01-01

    Of the various 'map' and 'compass' components of Kramer's avian navigational model, the long-range map component is the least well understood. In this paper atmospheric infrasounds are proposed as the elusive longrange cues constituting the avian navigational map. Although infrasounds were considered a viable candidate for the avian map in the 1970s, and pigeons in the laboratory were found to detect sounds at surprisingly low frequencies (0.05 Hz), other tests appeared to support either of the currently favored olfactory or magnetic maps. Neither of these hypotheses, however, is able to explain the full set of observations, and the field has been at an impasse for several decades. To begin, brief descriptions of infrasonic waves and their passage through the atmosphere are given, followed by accounts of previously unexplained release results. These examples include 'release-site biases' which are deviations of departing pigeons from the homeward bearing, an annual variation in homing performance observed only in Europe, difficulties orienting over lakes and above temperature inversions, and the mysterious disruption of several pigeon races. All of these irregularities can be consistently explained by the deflection or masking of infrasonic cues by atmospheric conditions or by other infrasonic sources (microbaroms, sonic booms), respectively. A source of continuous geographic infrasound generated by atmosphere-coupled microseisms is also proposed. In conclusion, several suggestions are made toward resolving some of the conflicting experimental data with the pigeons' possible use of infrasonic cues.

  14. Antigenic mapping of an H9N2 avian influenza virus reveals two discrete antigenic sites and a novel mechanism of immune escape

    Science.gov (United States)

    Peacock, Thomas; Reddy, Kolli; James, Joe; Adamiak, Beata; Barclay, Wendy; Shelton, Holly; Iqbal, Munir

    2016-01-01

    H9N2 avian influenza virus is a major cause of poultry production loss across Asia leading to the wide use of vaccines. Efficacy of vaccines is often compromised due to the rapid emergence of antigenic variants. To improve the effectiveness of vaccines in the field, a better understanding of the antigenic epitopes of the major antigen, hemagglutinin, is required. To address this, a panel of nine monoclonal antibodies were generated against a contemporary Pakistani H9N2 isolate, which represents a major Asian H9N2 viral lineage. Antibodies were characterized in detail and used to select a total of 26 unique ‘escape’ mutants with substitutions across nine different amino acid residues in hemagglutinin including seven that have not been described as antigenic determinants for H9N2 viruses before. Competition assays and structural mapping revealed two novel, discrete antigenic sites “H9-A” and “H9-B”. Additionally, a second subset of escape mutants contained amino acid deletions within the hemagglutinin receptor binding site. This constitutes a novel method of escape for group 1 hemagglutinins and could represent an alternative means for H9N2 viruses to overcome vaccine induced immunity. These results will guide surveillance efforts for arising antigenic variants as well as evidence based vaccine seed selection and vaccine design. PMID:26738561

  15. Curriculum Guide for Spanish Language Arts, Elementary Level F. Field Test = Guia para la ensenanza de las artes del lenguaje espanol, nivel elemental primario F. Edicion experimental.

    Science.gov (United States)

    Chicago Board of Education, IL. Dept. of Curriculum.

    The curriculum guide for teachers of Spanish language arts for native Spanish-speaking primary students in the Chicago public schools' bilingual education program is introduced by a section outlining the program and defining the areas to be emphasized in the program: word attack, comprehension skills, study skills, and literature appreciation.…

  16. Mathematics Curriculum Guide for Spanish-Speaking Students, Levels A, B, C, D, Field Test. Working Draft = Guia didactica de Matematicas, Niveles A, B, C, D. Edicion Experimental.

    Science.gov (United States)

    Chicago Board of Education, IL. Dept. of Curriculum.

    The introductory level curriculum guide for bilingual education for Spanish-speaking children in the Chicago public schools is divided into four difficulty levels and is designed to facilitate acquisition of mathematical concepts by presenting them in the children's native language. At each level, the concepts covered include the meaning of…

  17. Avian cytokines - the natural approach to therapeutics.

    Science.gov (United States)

    Lowenthal, J W; Lambrecht, B; van den Berg, T P; Andrew, M E; Strom, A D; Bean, A G

    2000-01-01

    While the effective use of antibiotics for the control of human disease has saved countless lives and has increased life expectancy over the past few decades, there are concerns arising from their usage in livestock. The use of antibiotic feed additives in food production animals has been linked to the emergence in the food chain of multiple drug-resistant bacteria that appear impervious to even the most powerful antimicrobial agents. Furthermore, the use of chemical antimicrobials has led to concerns involving environmental contamination and unwanted residues in food products. The imminent banning of antibiotic usage in livestock feed has intensified the search for environmentally-friendly alternative methods to control disease. Cytokines, as natural mediators and regulators of the immune response, offer exciting new alternatives to conventional chemical-based therapeutics. The utilisation of cytokines is becoming more feasible, particularly in poultry, with the recent cloning of a number of avian cytokine genes. Chickens offer an attractive small animal model system with which to study the effectiveness of cytokine therapy in the control of disease in intensive livestock. In this report we will review the status of avian cytokines and focus on our recent studies involving the therapeutic potential of chicken interferon gamma (ChIFN-gamma) as a vaccine adjuvant and a growth promoter. PMID:10717298

  18. Avian Bornaviruses in North American Gulls.

    Science.gov (United States)

    Guo, Jianhua; Tizard, Ian; Baroch, John; Shivaprasad, H L; Payne, Susan L

    2015-07-01

    Avian bornaviruses, recently described members of the family Bornaviridae, have been isolated from captive parrots and passerines as well as wild waterfowl in which they may cause lethal neurologic disease. We report detection of avian bornavirus RNA in the brains of apparently healthy gulls. We tested 439 gull brain samples from 18 states, primarily in the northeastern US, using a reverse-transcriptase PCR assay with primers designed to detect a conserved region of the bornavirus M gene. Nine birds yielded a PCR product of appropriate size. Sequencing of PCR products indicated that the virus was closely related to aquatic bird bornavirus 1 (ABBV-1). Viral RNA was detected in Herring Gulls (Larus argentatus), Ring-billed Gulls (Larus delawarensis), and Laughing Gulls (Leucophaeus atricilla). Eight of the nine positive birds came from the New York/New Jersey area. One positive Herring Gull came from New Hampshire. Histopathologic examination of one well-preserved brain from a Herring Gull from Union County New Jersey, showed a lymphocytic encephalitis similar to that observed in bornavirus-infected parrots and geese. Bornavirus N protein was confirmed in two Herring Gull brains by immunohistochemistry. Thus ABBV-1 can infect gulls and cause encephalitic brain lesions similar to those observed in other birds.

  19. Avian colibacillosis: still many black holes.

    Science.gov (United States)

    Guabiraba, Rodrigo; Schouler, Catherine

    2015-08-01

    Avian pathogenic Escherichia coli (APEC) strains cause severe respiratory and systemic diseases, threatening food security and avian welfare worldwide. Intensification of poultry production and the quick expansion of free-range production systems will increase the incidence of colibacillosis through greater exposure of birds to pathogens and stress. Therapy is mainly based on antibiotherapy and current vaccines have poor efficacy. Serotyping remains the most frequently used diagnostic method, only allowing the identification of a limited number of APEC strains. Several studies have demonstrated that the most common virulence factors studied in APEC are all rarely present in the same isolate, showing that APEC strains constitute a heterogeneous group. Different isolates may harbor different associations of virulence factors, each one able to induce colibacillosis. Despite its economical relevance, pathogenesis of colibacillosis is poorly understood. Our knowledge on the host response to APEC is based on very descriptive studies, mostly restricted to bacteriological and histopathological analysis of infected organs such as lungs. Furthermore, only a small number of APEC isolates have been used in experimental studies. In the present review, we discuss current knowledge on APEC diversity and virulence, including host response to infection and the associated inflammatory response with a focus on pulmonary colibacillosis. PMID:26204893

  20. Studying avian encephalization with geometric morphometrics.

    Science.gov (United States)

    Marugán-Lobón, Jesús; Watanabe, Akinobu; Kawabe, Soichiro

    2016-08-01

    Encephalization is a core concept in comparative neurobiology, aiming to quantify the neurological capacity of organisms. For measuring encephalization, many studies have employed relative brain sizes corrected for expected allometric scaling to body size. Here we highlight the utility of a multivariate geometric morphometric (GM) approach for visualizing and analyzing neuroanatomical shape variation associated with encephalization. GM readily allows the statistical evaluation of covariates, such as size, and many software tools exist for visualizing their effects on shape. Thus far, however, studies using GM have not attempted to translate the meaning of encephalization to shape data. As such, we tested the statistical relationship between size and encephalization quotients (EQs) to brain shape utilizing a broad interspecific sample of avian endocranial data. Although statistically significant, the analyses indicate that allometry accounts for <10% of total neuroanatomical shape variation. Notably, we find that EQs, despite being corrected for allometric scaling based on size, contain size-related neuroanatomical shape changes. In addition, much of what is traditionally considered encephalization comprises clade-specific trends in relative forebrain expansion, particularly driven by landbirds. EQs, therefore, fail to capture 90% of the total neuroanatomical variation after correcting for allometry and shared phylogenetic history. Moving forward, GM techniques provide crucial tools for investigating key drivers of this vast, largely unexplored aspect of avian brain morphology. PMID:27112986

  1. Collapsing avian community on a Hawaiian island

    Science.gov (United States)

    Paxton, Eben H.; Camp, Richard J.; Gorresen, P. Marcos; Crampton, Lisa H.; Leonard, David L.; VanderWerf, Eric A.

    2016-01-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing. PMID:27617287

  2. Avian Bornaviruses in North American Gulls.

    Science.gov (United States)

    Guo, Jianhua; Tizard, Ian; Baroch, John; Shivaprasad, H L; Payne, Susan L

    2015-07-01

    Avian bornaviruses, recently described members of the family Bornaviridae, have been isolated from captive parrots and passerines as well as wild waterfowl in which they may cause lethal neurologic disease. We report detection of avian bornavirus RNA in the brains of apparently healthy gulls. We tested 439 gull brain samples from 18 states, primarily in the northeastern US, using a reverse-transcriptase PCR assay with primers designed to detect a conserved region of the bornavirus M gene. Nine birds yielded a PCR product of appropriate size. Sequencing of PCR products indicated that the virus was closely related to aquatic bird bornavirus 1 (ABBV-1). Viral RNA was detected in Herring Gulls (Larus argentatus), Ring-billed Gulls (Larus delawarensis), and Laughing Gulls (Leucophaeus atricilla). Eight of the nine positive birds came from the New York/New Jersey area. One positive Herring Gull came from New Hampshire. Histopathologic examination of one well-preserved brain from a Herring Gull from Union County New Jersey, showed a lymphocytic encephalitis similar to that observed in bornavirus-infected parrots and geese. Bornavirus N protein was confirmed in two Herring Gull brains by immunohistochemistry. Thus ABBV-1 can infect gulls and cause encephalitic brain lesions similar to those observed in other birds. PMID:25973630

  3. Collapsing avian community on a Hawaiian island.

    Science.gov (United States)

    Paxton, Eben H; Camp, Richard J; Gorresen, P Marcos; Crampton, Lisa H; Leonard, David L; VanderWerf, Eric A

    2016-09-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua'i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species' ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua'i represents an early warning for the forest bird communities on the Maui and Hawai'i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing. PMID:27617287

  4. Collapsing avian community on a Hawaiian island

    Science.gov (United States)

    Paxton, Eben; Camp, Richard J.; Gorresen, P. Marcos; Crampton, Lisa H.; Leonard, David L.; VanderWerf, Eric

    2016-01-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing.

  5. Avian colibacillosis: still many black holes.

    Science.gov (United States)

    Guabiraba, Rodrigo; Schouler, Catherine

    2015-08-01

    Avian pathogenic Escherichia coli (APEC) strains cause severe respiratory and systemic diseases, threatening food security and avian welfare worldwide. Intensification of poultry production and the quick expansion of free-range production systems will increase the incidence of colibacillosis through greater exposure of birds to pathogens and stress. Therapy is mainly based on antibiotherapy and current vaccines have poor efficacy. Serotyping remains the most frequently used diagnostic method, only allowing the identification of a limited number of APEC strains. Several studies have demonstrated that the most common virulence factors studied in APEC are all rarely present in the same isolate, showing that APEC strains constitute a heterogeneous group. Different isolates may harbor different associations of virulence factors, each one able to induce colibacillosis. Despite its economical relevance, pathogenesis of colibacillosis is poorly understood. Our knowledge on the host response to APEC is based on very descriptive studies, mostly restricted to bacteriological and histopathological analysis of infected organs such as lungs. Furthermore, only a small number of APEC isolates have been used in experimental studies. In the present review, we discuss current knowledge on APEC diversity and virulence, including host response to infection and the associated inflammatory response with a focus on pulmonary colibacillosis.

  6. Avian malaria: a new lease of life for an old experimental model to study the evolutionary ecology of Plasmodium.

    Science.gov (United States)

    Pigeault, Romain; Vézilier, Julien; Cornet, Stéphane; Zélé, Flore; Nicot, Antoine; Perret, Philippe; Gandon, Sylvain; Rivero, Ana

    2015-08-19

    Avian malaria has historically played an important role as a model in the study of human malaria, being a stimulus for the development of medical parasitology. Avian malaria has recently come back to the research scene as a unique animal model to understand the ecology and evolution of the disease, both in the field and in the laboratory. Avian malaria is highly prevalent in birds and mosquitoes around the world and is amenable to laboratory experimentation at each stage of the parasite's life cycle. Here, we take stock of 5 years of experimental laboratory research carried out using Plasmodium relictum SGS1, the most prevalent avian malaria lineage in Europe, and its natural vector, the mosquito Culex pipiens. For this purpose, we compile and analyse data obtained in our laboratory in 14 different experiments. We provide statistical relationships between different infection-related parameters, including parasitaemia, gametocytaemia, host morbidity (anaemia) and transmission rates to mosquitoes. This analysis provides a wide-ranging picture of the within-host and between-host parameters that may bear on malaria transmission and epidemiology. PMID:26150666

  7. Risk Mapping of Highly Pathogenic Avian Influenza Distribution and Spread

    Directory of Open Access Journals (Sweden)

    Richard A. J. Williams

    2008-12-01

    Full Text Available The rapid emergence and spread of highly pathogenic H5N1 avian influenza begs effective and accurate mapping of current knowledge and future risk of infection. Methods for such mapping, however, are rudimentary, and few good examples exist for use as templates for risk-mapping efforts. We review the transmission cycle of avian influenza viruses, and identify points on which risk-mapping can focus. We provide examples from the literature and from our work that illustrate mapping risk based on (1 avian influenza case occurrences, (2 poultry distributions and movements, and (3 migratory bird movements.

  8. Replication of avian influenza A viruses in mammals.

    OpenAIRE

    Hinshaw, V S; Webster, R. G.; Easterday, B C; Bean, W J

    1981-01-01

    The recent appearance of an avian influenza A virus in seals suggests that viruses are transmitted from birds to mammals in nature. To examine this possibility, avian viruses of different antigenic subtypes were evaluated for their ability to replicate in three mammals-pigs, ferrets, and cats. In each of these mammals, avian strains replicated to high titers in the respiratory tract (10(5) to 10(7) 50% egg infective doses per ml of nasal wash), with peak titers at 2 to 4 days post-inoculation...

  9. AN EPIZOOTIC OF EMERGING NOVEL AVIAN POX IN CARRION CROWS (CORVUS CORONE) AND LARGE-BILLED CROWS (CORVUS MACRORHYNCHOS) IN JAPAN.

    Science.gov (United States)

    Fukui, Daisuke; Nakamura, Makiko; Yamaguchi, Tsuyoshi; Takenaka, Makiko; Murakami, Mami; Yanai, Tokuma; Fukushi, Hideto; Yanagida, Kazumi; Bando, Gen; Matsuno, Keita; Nagano, Masashi; Tsubota, Toshio

    2016-04-28

    In 2006-10, an epizootic of emerging avian pox occurred in Carrion Crows ( Corvus corone ) and Large-billed Crows ( Corvus macrorhynchos ), leading to mortality of juvenile crows in Hokkaido, the northernmost island of Japan. We diagnosed 27 crows with proliferative skin lesions (19 carcasses and eight biopsied cases [one in zoo captivity]) as avian pox clinically, histopathologically by detection of Avipoxvirus-specific 4b core protein (P4b) gene, and epidemiologically. The fatal cases demonstrated intensively severe infection and aggressive lesions with secondary bacterial infection. Since the first identification of avian pox in Sapporo, Japan, in 2006, the frequency of mortality events has increased, peaking in 2007-08. Mortalities have subsequently occurred in other areas, suggesting disease expansion. In Sapporo, prevalence of avian pox evaluated by field censuses during 2007-12 was 17.6% (6.6-27.2%), peaked during 2007-08 and 2008-09, and then decreased. All diseased crows were juveniles, except for one adult. The number of crows assembling in the winter roosts had been stable for >10 yr; however, it declined in 2007-08, decreased by about 50% in 2008-09, and recovered to the previous level in 2009-10, correlated with the avian pox outbreak. Thus, avian pox probably contributed to the unusual crow population decline. All P4b sequences detected in six specimens in Sapporo were identical and different from any previously reported sequences. The sequence detected in the zoo-kept crow was distinct from any reported clades, and interspecies transmission was suspected. This report demonstrates an emerging novel avian pox in the Japanese avifauna and in global populations of Carrion Crows and Large-billed Crows. Longitudinal monitoring is needed to evaluate its impact on the crow population. PMID:26967129

  10. The Helper Activities of Different Avian Viruses for Propagation of Recombinant Avian Adeno-Associated Virus

    Institute of Scientific and Technical Information of China (English)

    WANG An-ping; SUN Huai-chang; WANG Jian-ye; WANG Yong-juan; YUAN Wei-feng

    2007-01-01

    To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus (rAAAV), AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein (GFP) gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast (CEF) or chicken embryonic liver (CEL) cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek's disease virus (MDV), avian adenovirus, chicken embryo lethal orphan (CELO) virus or infectious bursal disease virus (IBDV). Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein (gfp) expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.

  11. The avian fossil record in Insular Southeast Asia and its implications for avian biogeography and palaeoecology

    Directory of Open Access Journals (Sweden)

    Hanneke J.M. Meijer

    2014-03-01

    Full Text Available Excavations and studies of existing collections during the last decades have significantly increased the abundance as well as the diversity of the avian fossil record for Insular Southeast Asia. The avian fossil record covers the Eocene through the Holocene, with the majority of bird fossils Pleistocene in age. Fossil bird skeletal remains represent at least 63 species in 54 genera and 27 families, and two ichnospecies are represented by fossil footprints. Birds of prey, owls and swiftlets are common elements. Extinctions seem to have been few, suggesting continuity of avian lineages since at least the Late Pleistocene, although some shifts in species ranges have occurred in response to climatic change. Similarities between the Late Pleistocene avifaunas of Flores and Java suggest a dispersal route across southern Sundaland. Late Pleistocene assemblages of Niah Cave (Borneo and Liang Bua (Flores support the rainforest refugium hypothesis in Southeast Asia as they indicate the persistence of forest cover, at least locally, throughout the Late Pleistocene and Holocene.

  12. The 3rd International Symposium on Avian Brood Parasitism

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Council of Norway, and China Ornithological Society (COS).

  13. Region 6 Avian Health Program FY2011 Annual Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report describes activities and fund allocations of the Region 6 Avian Health Program in FY2011. Activities include morbidity and mortality monitoring, disease...

  14. Transmission of Avian Influenza A Viruses Between Animals and People

    Science.gov (United States)

    ... Newsletters Transmission of Avian Influenza A Viruses Between Animals and People Language: English Español Recommend on ... Compartir Influenza A viruses have infected many different animals, including ducks, chickens, pigs, whales, horses, and seals. ...

  15. The avian tectorial membrane: Why is it tapered?

    CERN Document Server

    Iwasa, Kuni H

    2015-01-01

    While the mammalian- and the avian inner ears have well defined tonotopic organizations as well as hair cells specialized for motile and sensing roles, the structural organization of the avian ear is different from its mammalian cochlear counterpart. Presumably this difference stems from the difference in the way motile hair cells function. Short hair cells, whose role is considered analogous to mammalian outer hair cells, presumably depends on their hair bundles, and not motility of their cell body, in providing the motile elements of the cochlear amplifier. This report focuses on the role of the avian tectorial membrane, specifically by addressing the question, "Why is the avian tectorial membrane tapered from the neural to the abneural direction?"

  16. Migratory Bird Avian Influenza Sampling; Yukon Kuskokwim Delta, Alaska, 2015

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data set containing avian influenza sampling information for spring and summer waterbirds on the Yukon Kuskokwim Delta, 2015. Data contains sample ID, species...

  17. Avian populations and habitat use in interior Alaska taiga

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Avian community structure, habitat occupancy levels, and species habitat use patterns were examined in the woody habitats of interior Alaska taiga. Some birds...

  18. Avian Point Transect Survey; Seward Peninsula, Alaska, 2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data product contains avian point-transect survey data and habitat data collected on the Seward Peninsula, Alaska, USA, during 21 May – 10 June 2012. We...

  19. Historical review of avian botulism at Stillwater Wildlife Management Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to review historical information on avian botulism at Stillwater Wildlife Management Area. This report includes incidental reports of...

  20. Avian influenza surveillance sample collection and shipment protocol

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Instructions for mortality collection and shipment of avian influenza (AI) live bird surveillance sample collections. AI sample collections will include...

  1. Artist conception of the Avian Development Facility

    Science.gov (United States)

    2003-01-01

    The Avian Development Facility (ADF) supports 36 eggs in two carousels, one of which rotates to provide a 1-g control for comparing to eggs grown in microgravity. The ADF was designed to incubate up to 36 Japanese quail eggs, 18 in microgravity and 18 in artificial gravity. The two sets of eggs were exposed to otherwise identical conditions, the first time this is been accomplished in space. Eggs are preserved at intervals to provide snapshots of their development for later analysis. Quails incubate in just 15 days, so they are an ideal species to be studied within the duration of space shuttle missions. Further, several investigators can use the same specimens to address different questions. The ADF originated in NASA's Shuttle Student Involvement program in the 1980s and was developed under the NASA Small Business Irnovation Research program. In late 2001, the ADF made its first flight and carried eggs used in two investigations.

  2. 禽流感病%Avian Influenza

    Institute of Scientific and Technical Information of China (English)

    周先志

    1999-01-01

    @@ 禽流感病(avian influenza)是由甲型流感病毒引起的一种禽类疾病综合征.1997年5月,我国香港特别行政区1例3岁儿童死于不明原因的多器官功能衰竭,同年8月经美国疾病预防和控制中心以及WHO荷兰鹿特丹国家流感中心鉴定为禽甲型流感病毒H5N1[A(H5N1)]引起的人类流感[1~3].这是世界上首次证实A(H5N1)感染人类,因而引起医学界的广泛关注.

  3. 禽流感%Avian influenza

    Institute of Scientific and Technical Information of China (English)

    范学工; 龙云铸

    2005-01-01

    禽流感(avian influenza)是禽类流行性感冒的简称,是由甲型流感病毒株的某些亚型引起的急性呼吸道传染病。通常情况下,禽流感病毒并不感染人类,但自1997年禽甲型流感病毒H5N1感染人类之后,相继有H9N2、H7N7.亚型感染人类和H5N1再次感染人类的报道,引起了世人的广泛关注。

  4. Infrasound and the avian navigational map

    Science.gov (United States)

    Hagstrum, J.T.

    2001-01-01

    Birds can accurately navigate over hundreds to thousands of kilometres, and use celestial and magnetic compass senses to orient their flight. How birds determine their location in order to select the correct homeward bearing (map sense) remains controversial, and has been attributed to their olfactory or magnetic senses. Pigeons can hear infrasound down to 0??05 Hz, and an acoustic avian map is proposed consisting of infrasonic cues radiated from steep-sided topographic features. The source of these infrasonic signals is microseisms continuously generated by interfering oceanic waves. Atmospheric processes affecting the infrasonic map cues can explain perplexing experimental results from pigeon releases. Moreover, four recent disrupted pigeon races in Europe and the north-eastern USA intersected infrasonic shock waves from the Concorde supersonic transport. Having an acoustic map might also allow clock-shifted birds to test their homeward progress and select between their magnetic and solar compasses.

  5. Seroprevalence of avian pneumovirus in Minnesota turkeys.

    Science.gov (United States)

    Goyal, Sagar M; Lauer, Dale; Friendshuh, Keith; Halvorson, David A

    2003-01-01

    Avian pneumovirus (APV) causes respiratory tract infection in turkeys and was first seen in the United States in Colorado in late 1996. In early 1997, the disease was recognized in Minnesota and caused estimated losses of up to 15 million dollars per year. This virus has not been reported in the other turkey producing states. We here report the seroprevalence of APV in Minnesota from August 1998 to July 2002. The average rate of seroprevalence has been 36.3% (range = 14.2%-64.8%). A seasonal bias was observed, with peak incidences in the fall and spring. A higher rate of seropositivity was observed in counties with the highest concentration of turkeys.

  6. A glossary for avian conservation biology

    Science.gov (United States)

    Koford, Rolf R.; Dunning, J.B., Jr.; Ribic, C.A.; Finch, D.M.

    1994-01-01

    This glossary provides standard definitions for many of the terms used in avian conservation biology. We compiled these definitions to assist communication among researchers, managers, and others involved in the Neotropical Migratory Bird Conservation Program, also known as Partners in Flight. We used existing glossaries and recent literature to prepare this glossary. The cited sources were not necessarily the first ones to use the terms. Many definitions were taken verbatim from the cited source material. Others were modified slightly to clarify the meaning. Definitions that were modified to a greater extent are indicated as being adapted from the originals. Terms that have been used in more than one way by different authors are listed with numbered alternative definitions if the definitions differ substantially.

  7. Avian ecology of arid habitats in Namibia / Henriette Cornelia Potgieter

    OpenAIRE

    Potgieter, Henriette Cornelia

    2015-01-01

    Examination of bird assemblages along an environmental gradient which encompasses both climate and habitat change is needed if we are to better understand the potential effects of these changes for avians and the ecological process that depend upon them. Climate change is predicted to have a significant impact on deserts and desert margins, resulting in distributional shifts of entire ecosystems and new community associations. This study explores the probable responses of avian communities to...

  8. The role of the avian hippocampus in spatial memory.

    OpenAIRE

    Macphail E. M.

    2002-01-01

    Avian hippocampal function is surveyed, using data drawn from three areas: conventional laboratory paradigms, pigeon navigation, and food-storing. Damage to the avian hippocampus disrupts performance in laboratory tasks that tap spatial learning and memory, and also disrupts both pigeon homing and cache recovery by food-storing birds. Further evidence of hippocampal involvement in food-storing is provided by the fact that the hippocampus of food-storing birds is ...

  9. Avian-like breathing mechanics in maniraptoran dinosaurs

    OpenAIRE

    Codd, Jonathan R.; Phillip L. Manning; Mark A Norell; Perry, Steven F.

    2007-01-01

    In 1868 Thomas Huxley first proposed that dinosaurs were the direct ancestors of birds and subsequent analyses have identified a suite of ‘avian’ characteristics in theropod dinosaurs. Ossified uncinate processes are found in most species of extant birds and also occur in extinct non-avian maniraptoran dinosaurs. Their presence in these dinosaurs represents another morphological character linking them to Aves, and further supports the presence of an avian-like air-sac respiratory system in th...

  10. Predicting power-optimal kinematics of avian wings

    OpenAIRE

    Parslew, Ben

    2015-01-01

    A theoretical model of avian flight is developed which simulates wing motion through a class of methods known as predictive simulation. This approach uses numerical optimization to predict power-optimal kinematics of avian wings in hover, cruise, climb and descent. The wing dynamics capture both aerodynamic and inertial loads. The model is used to simulate the flight of the pigeon, Columba livia, and the results are compared with previous experimental measurements. In cruise, the model uneart...

  11. Low-pathogenic avian influenza viruses in wild house mice.

    Directory of Open Access Journals (Sweden)

    Susan A Shriner

    Full Text Available BACKGROUND: Avian influenza viruses are known to productively infect a number of mammal species, several of which are commonly found on or near poultry and gamebird farms. While control of rodent species is often used to limit avian influenza virus transmission within and among outbreak sites, few studies have investigated the potential role of these species in outbreak dynamics. METHODOLOGY/PRINCIPAL FINDINGS: We trapped and sampled synanthropic mammals on a gamebird farm in Idaho, USA that had recently experienced a low pathogenic avian influenza outbreak. Six of six house mice (Mus musculus caught on the outbreak farm were presumptively positive for antibodies to type A influenza. Consequently, we experimentally infected groups of naïve wild-caught house mice with five different low pathogenic avian influenza viruses that included three viruses derived from wild birds and two viruses derived from chickens. Virus replication was efficient in house mice inoculated with viruses derived from wild birds and more moderate for chicken-derived viruses. Mean titers (EID(50 equivalents/mL across all lung samples from seven days of sampling (three mice/day ranged from 10(3.89 (H3N6 to 10(5.06 (H4N6 for the wild bird viruses and 10(2.08 (H6N2 to 10(2.85 (H4N8 for the chicken-derived viruses. Interestingly, multiple regression models indicated differential replication between sexes, with significantly (p<0.05 higher concentrations of avian influenza RNA found in females compared with males. CONCLUSIONS/SIGNIFICANCE: Avian influenza viruses replicated efficiently in wild-caught house mice without adaptation, indicating mice may be a risk pathway for movement of avian influenza viruses on poultry and gamebird farms. Differential virus replication between males and females warrants further investigation to determine the generality of this result in avian influenza disease dynamics.

  12. Surveillance of wild birds for avian influenza virus

    OpenAIRE

    Hoye, B.; Munster, V.J.; Nishiura, H.M.; Klaassen, M.; Fouchier, R. A. M.

    2010-01-01

    Recent demand for increased understanding of avian infl uenza virus in its natural hosts, together with the development of high-throughput diagnostics, has heralded a new era in wildlife disease surveillance. However, survey design, sampling, and interpretation in the context of host populations still present major challenges. We critically reviewed current surveillance to distill a series of considerations pertinent to avian infl uenza virus surveillance in wild birds, including consideratio...

  13. Detecting emerging transmissibility of avian influenza virus in human households

    OpenAIRE

    van Boven, M.; Koopmans, M.; Du Ry van Beest Holle, M.; Meijer, Adam; Klinkenberg, D.; Donnelly, C. A.; Heesterbeek, J A P

    2007-01-01

    Accumulating infections of highly pathogenic H5N1 avian influenza in humans underlines the need to track the ability of these viruses to spread among humans. A human-transmissible avian influenza virus is expected to cause clusters of infections in humans living in close contact. Therefore, epidemiological analysis of infection clusters in human households is of key importance. Infection clusters may arise from transmission events from (i) the animal reservoir, (ii) humans who were infected b...

  14. Avian bornavirus in the urine of infected birds

    OpenAIRE

    Heatley, J. Jill; Villalobos, de, Leonor Cristina

    2012-01-01

    J Jill Heatley,1 Alice R Villalobos21Zoological Medicine, 2Department of Nutrition & Food Science, Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, College Station, TX, USAAbstract: Avian bornavirus (ABV) causes proventricular dilatation disease in multiple avian species. In severe clinical disease, the virus, while primarily neurotropic, can be detected in many organs, including the kidneys. We postulated that ABV could be shed by the kidneys and ...

  15. Identifying avian sources of faecal contamination using sterol analysis.

    Science.gov (United States)

    Devane, Megan L; Wood, David; Chappell, Andrew; Robson, Beth; Webster-Brown, Jenny; Gilpin, Brent J

    2015-10-01

    Discrimination of the source of faecal pollution in water bodies is an important step in the assessment and mitigation of public health risk. One tool for faecal source tracking is the analysis of faecal sterols which are present in faeces of animals in a range of distinctive ratios. Published ratios are able to discriminate between human and herbivore mammal faecal inputs but are of less value for identifying pollution from wildfowl, which can be a common cause of elevated bacterial indicators in rivers and streams. In this study, the sterol profiles of 50 avian-derived faecal specimens (seagulls, ducks and chickens) were examined alongside those of 57 ruminant faeces and previously published sterol profiles of human wastewater, chicken effluent and animal meatwork effluent. Two novel sterol ratios were identified as specific to avian faecal scats, which, when incorporated into a decision tree with human and herbivore mammal indicative ratios, were able to identify sterols from avian-polluted waterways. For samples where the sterol profile was not consistent with herbivore mammal or human pollution, avian pollution is indicated when the ratio of 24-ethylcholestanol/(24-ethylcholestanol + 24-ethylcoprostanol + 24-ethylepicoprostanol) is ≥0.4 (avian ratio 1) and the ratio of cholestanol/(cholestanol + coprostanol + epicoprostanol) is ≥0.5 (avian ratio 2). When avian pollution is indicated, further confirmation by targeted PCR specific markers can be employed if greater confidence in the pollution source is required. A 66% concordance between sterol ratios and current avian PCR markers was achieved when 56 water samples from polluted waterways were analysed.

  16. Avian influenza in Croatia - Current status

    International Nuclear Information System (INIS)

    Full text: Wild birds can carry a wide range of viral and other zoonotic agents, which may be transmitted to humans. From October 2005 to March 2006 HPAI H5N1 virus was isolated from wild birds (mute swans, black-headed gulls and a mallard duck) in Croatia at five locations. After isolation of H5N1 virus at 2006 from mallard duck near City of Zagreb (capital of Croatia) Department of Poultry Diseases with Clinic at the Faculty of Veterinary Medicine, has conducted monitoring of avian viruses that could endanger human health. Samples (999 pharyngeal and cloacal swabs) from 23 wild bird species were taken. After year 2006 Croatia has regular monitoring for avian influenza in wild birds and poultry (especially in the backyard flocks). During 2007 (6,928 wild birds and 18,000 blood samples from poultry) and 2008 (2,486 wild birds; 20,000 blood samples and 1,500 cloacal swabs from poultry) were taken. Isolation was performed with classical virus detection method by inoculation of 10 day old chicken embryos, and molecular methods by conventional PCR and Real Time PCR (M gene, H5, H7 and N1 genes), and serological methods by antibody detection from blood samples (inhibition hemagglutination and ELISA). All samples were HPAI virus negative but investigators from the Poultry Centre of the Croatian Veterinary Institute isolated from wild birds LPAI viruses: H2N3, H3N8, H5N3 and H10N7. The results obtained by these investigations and monitoring revealed the need for permanent monitoring of wild bird's health status, especially the water birds species. Vaccination against AI is never practiced in Croatia. Quick and accurate detection of wild migratory birds infected with the H5N1 virus prevented the spread of the virus to the domestic poultry in Croatia which would have had enormous consequences. (author)

  17. Early warning: Avian flu and nuclear science

    International Nuclear Information System (INIS)

    Avian flu has spread to 51 countries, 36 this year alone, many of which are densely populated and deprived. The joint FAO/IAEA programme is working on the rapid detection of emerging diseases, including bird flu, and using nuclear and radiation techniques in the process. The problems are serious and challenging, but nuclear technologies may offer a solution. For most developing countries, TAD (transboundary animal diseases) detection is still vital. The bottleneck is their inability to rapidly detect the virus and to determine early enough whether it is H5N1 or another subtype, so that authorities can take appropriate control measures. Serious efforts are focused on the early detection of the agents. Timely recognition of such viral infections would prevent the spread of the diseases to large animal populations in huge geographic areas. Thus, the development of novel, powerful diagnostic nuclear and nuclear-related assays is a crucial issue today in veterinary research and animal health care. Molecular virology offers a range of new methods, which are able to accelerate and improve the diagnosis of infectious diseases in animals and in man. The molecular detection assays, like the polymerase chain reaction (PCR) technologies, provide possibilities for a very rapid diagnosis. The detection of viruses can be completed within hours or hopefully even within minutes with a sensitivity level of less than one pathogenic organism. Molecular approaches have contributed significantly to the rapid detection of well-established, as well as newly emerging, infectious agents such as Nipah and Hendra viruses or corona viruses in the SARS scenario and the detection and molecular characterisation of the highly pathogenic avian influenza H5N1 subtype that threatens the world today. The nucleic acid amplification assays, although they were at first expensive and cumbersome, have become relatively cheap and user-friendly tools in the diagnostic laboratories

  18. Avian magnetic compass: Its functional properties and physical basis

    Directory of Open Access Journals (Sweden)

    Roswitha WILTSCHKO, Wolfgang WILTSCHKO

    2010-06-01

    Full Text Available The avian magnetic compass was analyzed in bird species of three different orders – Passeriforms, Columbiforms and Galliforms – and in three different behavioral contexts, namely migratory orientation, homing and directional conditioning. The respective findings indicate similar functional properties: it is an inclination compass that works only within a functional window around the ambient magnetic field intensity; it tends to be lateralized in favor of the right eye, and it is wavelength-dependent, requiring light from the short-wavelength range of the spectrum. The underlying physical mechanisms have been identified as radical pair processes, spin-chemical reactions in specialized photopigments. The iron-based receptors in the upper beak do not seem to be involved. The existence of the same type of magnetic compass in only very distantly related bird species suggests that it may have been present already in the common ancestors of all modern birds, where it evolved as an all-purpose compass mechanism for orientation within the home range [Current Zoology 56 (3: 265–276, 2010].

  19. Estradiol selectively enhances auditory function in avian forebrain neurons.

    Science.gov (United States)

    Caras, Melissa L; O'Brien, Matthew; Brenowitz, Eliot A; Rubel, Edwin W

    2012-12-01

    Sex steroids modulate vertebrate sensory processing, but the impact of circulating hormone levels on forebrain function remains unclear. We tested the hypothesis that circulating sex steroids modulate single-unit responses in the avian telencephalic auditory nucleus, field L. We mimicked breeding or nonbreeding conditions by manipulating plasma 17β-estradiol levels in wild-caught female Gambel's white-crowned sparrows (Zonotrichia leucophrys gambelii). Extracellular responses of single neurons to tones and conspecific songs presented over a range of intensities revealed that estradiol selectively enhanced auditory function in cells that exhibited monotonic rate level functions to pure tones. In these cells, estradiol treatment increased spontaneous and maximum evoked firing rates, increased pure tone response strengths and sensitivity, and expanded the range of intensities over which conspecific song stimuli elicited significant responses. Estradiol did not significantly alter the sensitivity or dynamic ranges of cells that exhibited non-monotonic rate level functions. Notably, there was a robust correlation between plasma estradiol concentrations in individual birds and physiological response properties in monotonic, but not non-monotonic neurons. These findings demonstrate that functionally distinct classes of anatomically overlapping forebrain neurons are differentially regulated by sex steroid hormones in a dose-dependent manner.

  20. Pasteurella multocida from outbreaks of avian cholera in wild and captive birds in Denmark

    DEFF Research Database (Denmark)

    Pedersen, Karl; Dietz, Hans-Henrik; Jørgensen, J.C.;

    2003-01-01

    An outbreak of avian cholera was observed among wild birds in a few localities in Denmark in 2001. The highest mortalities were among breeding ciders (Somateria mollissima) and gulls (Larus spp.). Pulsed-field gel electrophoresis (PFGE) was conducted using ApaI and SmaI as restriction enzymes...... and restriction enzyme analysis (REA) using HpaII. The Pasteurella multocida subsp. multocida strain isolated from birds in this outbreak was indistinguishable from a strain that caused outbreaks in 1996 and 2003. Most isolates from domestic poultry had other PFGE patterns but some were indistinguishable from...

  1. Avian Distribution and Habitat, Colonial Bird Data; The annual colonial nesting bird count is conducted by the RIDEM Division of Fish and Wildlife, Published in 2004, 1:12000 (1in=1000ft) scale, State of Rhode Island and Providence Plantations.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Avian Distribution and Habitat dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Field Survey/GPS information as of 2004. It...

  2. Avian Distribution and Habitat, Radiotagged migrating bats will be detected at automated receiving stations deployed around Lake Erie and in southern Ontario. Bat movements will be identified by the sequential order of towers on which they are detected., Published in 2015-2017, Not Applicable scale, Pennsylvania Coastal Resources Management Program.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Avian Distribution and Habitat dataset, published at Not Applicable scale, was produced all or in part from Field Observation information as of 2015-2017. It...

  3. Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

    Directory of Open Access Journals (Sweden)

    Sanhong Liu

    2015-01-01

    Full Text Available Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza.

  4. Avian Antimicrobial Host Defense Peptides: From Biology to Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Guolong Zhang

    2014-02-01

    Full Text Available Host defense peptides (HDPs are an important first line of defense with antimicrobial and immunomoduatory properties. Because they act on the microbial membranes or host immune cells, HDPs pose a low risk of triggering microbial resistance and therefore, are being actively investigated as a novel class of antimicrobials and vaccine adjuvants. Cathelicidins and β-defensins are two major families of HDPs in avian species. More than a dozen HDPs exist in birds, with the genes in each HDP family clustered in a single chromosomal segment, apparently as a result of gene duplication and diversification. In contrast to their mammalian counterparts that adopt various spatial conformations, mature avian cathelicidins are mostly α-helical. Avian β-defensins, on the other hand, adopt triple-stranded β-sheet structures similar to their mammalian relatives. Besides classical β-defensins, a group of avian-specific β-defensin-related peptides, namely ovodefensins, exist with a different six-cysteine motif. Like their mammalian counterparts, avian cathelicidins and defensins are derived from either myeloid or epithelial origin expressed in a majority of tissues with broad-spectrum antibacterial and immune regulatory activities. Structure-function relationship studies with several avian HDPs have led to identification of the peptide analogs with potential for use as antimicrobials and vaccine adjuvants. Dietary modulation of endogenous HDP synthesis has also emerged as a promising alternative approach to disease control and prevention in chickens.

  5. Lack of evidence of endogenous avian leukosis virus and endogenous avian retrovirus transmission to measles, mumps, and rubella vaccine recipients.

    OpenAIRE

    Hussain, A. I.; V. Shanmugam; Switzer, W. M.; Tsang, S. X.; Fadly, A.; Thea, D.; Helfand, R; Bellini, W J; Folks, T M; Heneine, W

    2001-01-01

    The identification of endogenous avian leukosis virus (ALV) and endogenous avian retrovirus (EAV) in chick cell-derived measles and mumps vaccines in current use has raised concern about transmission of these retroviruses to vaccine recipients. We used serologic and molecular methods to analyze specimens from 206 recipients of measles, mumps, and rubella (MMR) vaccine for evidence of infection with ALV and EAV. A Western blot assay for detecting antibodies to endogenous ALV was developed and ...

  6. The chicken as a natural model for extraintestinal infections caused by avian pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Antão, Esther-Maria; Glodde, Susanne; Li, Ganwu; Sharifi, Reza; Homeier, Timo; Laturnus, Claudia; Diehl, Ines; Bethe, Astrid; Philipp, Hans-C; Preisinger, Rudolf; Wieler, Lothar H; Ewers, Christa

    2008-01-01

    E. coli infections in avian species have become an economic threat to the poultry industry worldwide. Several factors have been associated with the virulence of E. coli in avian hosts, but no specific virulence gene has been identified as being entirely responsible for the pathogenicity of avian pathogenic E. coli (APEC). Needless to say, the chicken would serve as the best model organism for unravelling the pathogenic mechanisms of APEC, an extraintestinal pathogen. Five-week-old white leghorn SPF chickens were infected intra-tracheally with a well characterized APEC field strain IMT5155 (O2:K1:H5) using different doses corresponding to the respective models of infection established, that is, the lung colonization model allowing re-isolation of bacteria only from the lung but not from other internal organs, and the systemic infection model. These two models represent the crucial steps in the pathogenesis of APEC infections, including the colonization of the lung epithelium and the spread of bacteria throughout the bloodstream. The read-out system includes a clinical score, pathomorphological changes and bacterial load determination. The lung colonization model has been established and described for the first time in this study, in addition to a comprehensive account of a systemic infection model which enables the study of severe extraintestinal pathogenic E. coli (ExPEC) infections. These in vivo models enable the application of various molecular approaches to study host-pathogen interactions more closely. The most important application of such genetic manipulation techniques is the identification of genes required for extraintestinal virulence, as well as host genes involved in immunity in vivo. The knowledge obtained from these studies serves the dual purpose of shedding light on the nature of virulence itself, as well as providing a route for rational attenuation of the pathogen for vaccine construction, a measure by which extraintestinal infections, including

  7. Avian influenza viruses - new causative a gents of human infections

    Directory of Open Access Journals (Sweden)

    Hrnjaković-Cvjetković Ivana

    2006-01-01

    Full Text Available Introduction. Influenza A viruses can infect humans, some mammals and especially birds. Subtypes of human influenza A viruses: ACH1N1, ACH2N2 and A(H3N2 have caused pandemics. Avian influenza viruses vary owing to their 15 hemagglutinins (H and 9 neuraminidases (N. Human cases of avian influenza A In the Netherlands in 2003, there were 83 human cases of influenza A (H7N7. In 1997, 18 cases of H5N1 influenza A, of whom 6 died, were found among residents of Hong Kong. In 2004, 34 human cases (23 deaths were reported in Viet Nam and Thailand. H5N1 virus-infected patients presented with fever and respiratory symptoms. Complications included respiratory distress syndrome, renal failure, liver dysfunction and hematologic disorders. Since 1999, 7 cases of human influenza H9N2 infection have been identified in China and Hong Kong. The importance of human infection with avian influenza viruses. H5N1 virus can directly infect humans. Genetic reassortment of human and avian influenza viruses may occur in humans co infected with current human A(HIN1 or A(H3N2 subtypes and avian influenza viruses. The result would be a new influenza virus with pandemic potential. All genes of H5Nl viruses isolated from humans are of avian origin. Prevention and control. The reassortant virus containing H and N from avian and the remaining proteins from human influenza viruses will probably be used as a vaccine strain. The most important control measures are rapid destruction of all infected or exposed birds and rigorous disinfection of farms. Individuals exposed to suspected animals should receive prophylactic treatment with antivirals and annual vaccination. .

  8. Access to health information may improve behavior in preventing Avian influenza among women

    OpenAIRE

    Ajeng T. Endarti; Shamsul A. Shah

    2011-01-01

    Background: Improving human behavior toward Avian influenza may lessen the chance to be infected by Avian influenza. This study aimed to identify several factors influencing behavior in the community.Method: A cross-sectional study was conducted in July 2008. Behavior regarding Avian influenza was measured by scoring the variables of knowledge, attitude, and practice. Subjects were obtained from the sub district of Limo, in Depok, West Java, which was considered a high risk area for Avian inf...

  9. Risks of avian influenza transmission in areas of intensive free-ranging duck production with wild waterfowl

    Science.gov (United States)

    Cappelle, Julien; Zhao, Delong; Gilbert, Marius; Newman, Scott H.; Takekawa, John Y.; Gaidet, Nicolas; Prosser, Diann J.; Liu, Ying; Li, Peng; Shu, Yuelong; Xiao, Xiangming

    2014-01-01

    For decades, southern China has been considered to be an important source for emerging influenza viruses since key hosts live together in high densities in areas with intensive agriculture. However, the underlying conditions of emergence and spread of avian influenza viruses (AIV) have not been studied in detail, particularly the complex spatiotemporal interplay of viral transmission between wild and domestic ducks, two major actors of AIV epidemiology. In this synthesis, we examine the risks of avian influenza spread in Poyang Lake, an area of intensive free-ranging duck production and large numbers of wild waterfowl. Our synthesis shows that farming of free-grazing domestic ducks is intensive in this area and synchronized with wild duck migration. The presence of juvenile domestic ducks in harvested paddy fields prior to the arrival and departure of migrant ducks in the same fields may amplify the risk of AIV circulation and facilitate the transmission between wild and domestic populations. We provide evidence associating wild ducks migration with the spread of H5N1 in the spring of 2008 from southern China to South Korea, Russia, and Japan, supported by documented wild duck movements and phylogenetic analyses of highly pathogenic avian influenza H5N1 sequences. We suggest that prevention measures based on a modification of agricultural practices may be implemented in these areas to reduce the intensity of AIV transmission between wild and domestic ducks. This would require involving all local stakeholders to discuss feasible and acceptable solutions.

  10. Avian Predation on Juvenile Salmonids in the Lower Columbia River: 1997 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Roby, Daniel D.; Craig, David P.; Collis, Ken; Adamany, Stephanie L.

    1998-09-01

    The authors initiated a field study in 1997 to assess the impacts of fish-eating colonial waterbirds (i.e., terns, cormorants, and gulls) on the survival of juvenile salmonids in the lower Columbia River. Here the authors present results from the 1998 breeding season, the second field season of work on this project. The research objectives in 1998 were to: (1) determine the location, size, nesting chronology, nesting success, and population trajectories of breeding colonies of fish-eating birds in the lower Columbia River; (2) determine diet composition of fish-eating birds, including taxonomic composition and energy content of various prey types; (3) estimate forage fish consumption rates, with special emphasis on juvenile salmonids, by breeding adults and their young; (4) determine the relative vulnerabilit2048 different groups of juvenile salmonids to bird predation; (5) identify foraging range, foraging strategies, and habitat utilization by piscivorous waterbirds; and (6) test the feasibility of various alternative methods for managing avian predation on juvenile salmonids and develop recommendations to reduce avian predation, if warranted by the results.

  11. Avian Predation on Juvenile Salmonids in the Lower Columbia River: 1998 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Collis, Ken; Adamany, Stephanie; Roby, Daniel D.; Craig, David P.; Lyons, Donald E.

    2000-04-01

    The authors initiated a field study in 1997 to assess the impacts of fish-eating colonial waterbirds (i.e., terns, cormorants, and gulls) on the survival of juvenile salmonids in the lower Columbia River. Here the authors present results from the 1998 breeding season, the second field season of work on this project. The research objectives in 1998 were to: (1) determine the location, size, nesting chronology, nesting success, and population trajectories of breeding colonies of fish-eating birds in the lower Columbia River; (2) determine diet composition of fish-eating birds, including taxonomic composition and energy content of various prey types; (3) estimate forage fish consumption rates, with special emphasis on juvenile salmonids, by breeding adults and their young; (4) determine the relative vulnerability of different groups of juvenile salmonids to bird predation; (5) identify foraging range, foraging strategies, and habitat utilization by piscivorous waterbirds; and (6) test the feasibility of various alternative methods for managing avian predation on juvenile salmonids and develop recommendations to reduce avian predation, if warranted by the results.

  12. A pmp genes-based PCR as a valuable tool for the diagnosis of avian chlamydiosis.

    Science.gov (United States)

    Laroucau, Karine; Trichereau, Alain; Vorimore, Fabien; Mahé, Anne-Marie

    2007-03-31

    In a previous study we described the use of a new set of PCR primers (CpsiA/CpsiB) specific of the conserved pmp-family genes of Chlamydophila abortus as an efficient tool for the detection of these bacteria in ruminants including also preliminary results on avian strains. In this work, the use of this set of primers was extended to representative strains of the six major avian serovars (serovars A-F) and to field isolates of C. psittaci. For all the studied representative strains, using purified genomic DNA as a template, CpsiA/CpsiB primers allowed, as observed for C. abortus, a minimal 10-fold PCR signal increase compared to the one observed with ompA specific primers. In comparison to primers targeting the 16S-23S rRNA intergenic spacer, similar or increased sensitivity was observed depending on the strain. All the field isolates were amplified with CpsiA/CpsiB primers. On clinical samples, our primers are the best among those tested for detection of C. psittaci by simple conventional PCR. RFLP experiments performed using PCR fragments amplified with the CpsiA/CpsiB primers gave promising results demonstrating that these primers may provide an interesting tool for molecular typing when the bacterium cannot be grown from pathological samples.

  13. Avian predation on juvenile salmonids in the Lower Columbia River; 1998 annual report

    International Nuclear Information System (INIS)

    The authors initiated a field study in 1997 to assess the impacts of fish-eating colonial waterbirds (i.e., terns, cormorants, and gulls) on the survival of juvenile salmonids in the lower Columbia River. Here the authors present results from the 1998 breeding season, the second field season of work on this project. The research objectives in 1998 were to: (1) determine the location, size, nesting chronology, nesting success, and population trajectories of breeding colonies of fish-eating birds in the lower Columbia River; (2) determine diet composition of fish-eating birds, including taxonomic composition and energy content of various prey types; (3) estimate forage fish consumption rates, with special emphasis on juvenile salmonids, by breeding adults and their young; (4) determine the relative vulnerability of different groups of juvenile salmonids to bird predation; (5) identify foraging range, foraging strategies, and habitat utilization by piscivorous waterbirds; and (6) test the feasibility of various alternative methods for managing avian predation on juvenile salmonids and develop recommendations to reduce avian predation, if warranted by the results

  14. Planning and executing a vaccination campaign against avian influenza.

    Science.gov (United States)

    Marangon, S; Cristalli, A; Busani, L

    2007-01-01

    Vaccination against avian influenza infection caused by H5 or H7 virus subtypes has been used on several occasions in recent years to control and in some cases eradicate the disease. In order to contain avian influenza infection effectively, immunization should be combined with a coordinated set of control and monitoring measures. The outcome of an immunization campaign depends on the territorial strategy; whereas the capacity of the veterinary services in developed countries permits enforcement of strategies aimed at eradicating avian influenza, many countries currently affected by highly pathogenic avian influenza (HPAI) H5N1 viruses have a limited veterinary infrastructure and a limited capacity to respond to such epidemics. In these countries, resources are still insufficient to conduct adequate surveillance for identification and reaction to avian influenza outbreaks when they occur. When properly applied in this scenario, immunization can reduce mortality and production losses. In the long term, immunization might also decrease the prevalence of infection to levels at which stamping-out and surveillance can be applied. Countries should adapt their immunization programmes to local conditions in order to guarantee their efficacy and sustainability. In the initial emergency phase, human resources can be mobilized, with reliance on personal responsibility and motivation, thus compensating for potential shortcomings in organization. A more appropriate allocation of resources must be pursued in the long term, remembering that biosecurity is the main component of an exit strategy and must always be improved.

  15. Avian influenza survey in migrating waterfowl in Sonora, Mexico.

    Science.gov (United States)

    Montalvo-Corral, M; López-Robles, G; Hernández, J

    2011-02-01

    A two-year survey was carried out on the occurrence of avian influenza in migrating birds in two estuaries of the Mexican state of Sonora, which is located within the Pacific flyway. Cloacal and oropharyngeal swabs were collected from 1262 birds, including 20 aquatic bird species from the Moroncarit and Tobari estuaries in Sonora, Mexico. Samples were tested for type A influenza (M), H5 Eurasian and North American subtypes (H5EA and H5NA respectively) and the H7 North American subtype (H7NA). Gene detection was determined by one-step real-time reverse transcription polymerase chain reaction (RRT-PCR). The results revealed that neither the highly pathogenic avian influenza virus H5 of Eurasian lineage nor H7NA were detected. The overall prevalence of avian influenza type A (M-positive) in the sampled birds was 3.6% with the vast majority in dabbling ducks (Anas species). Samples from two birds, one from a Redhead (Aythya americana) and another from a Northern Shoveler (Anas clypeata), were positive for the low-pathogenic H5 avian influenza virus of North American lineage. These findings represented documented evidence of the occurrence of avian influenza in wintering birds in the Mexican wetlands. This type of study contributes to the understanding of how viruses spread to new regions of North America and highlights the importance of surveillance for the early detection and control of potentially pathogenic strains, which could affect animal and human health.

  16. Next generation sequencing technologies: tool to study avian virus diversity.

    Science.gov (United States)

    Kapgate, S S; Barbuddhe, S B; Kumanan, K

    2015-03-01

    Increased globalisation, climatic changes and wildlife-livestock interface led to emergence of novel viral pathogens or zoonoses that have become serious concern to avian, animal and human health. High biodiversity and bird migration facilitate spread of the pathogen and provide reservoirs for emerging infectious diseases. Current classical diagnostic methods designed to be virus-specific or aim to be limited to group of viral agents, hinder identifying of novel viruses or viral variants. Recently developed approaches of next-generation sequencing (NGS) provide culture-independent methods that are useful for understanding viral diversity and discovery of novel virus, thereby enabling a better diagnosis and disease control. This review discusses the different possible steps of a NGS study utilizing sequence-independent amplification, high-throughput sequencing and bioinformatics approaches to identify novel avian viruses and their diversity. NGS lead to the identification of a wide range of new viruses such as picobirnavirus, picornavirus, orthoreovirus and avian gamma coronavirus associated with fulminating disease in guinea fowl and is also used in describing viral diversity among avian species. The review also briefly discusses areas of viral-host interaction and disease associated causalities with newly identified avian viruses. PMID:25790045

  17. Detecting emerging transmissibility of avian influenza virus in human households.

    Directory of Open Access Journals (Sweden)

    Michiel van Boven

    2007-07-01

    Full Text Available Accumulating infections of highly pathogenic H5N1 avian influenza in humans underlines the need to track the ability of these viruses to spread among humans. A human-transmissible avian influenza virus is expected to cause clusters of infections in humans living in close contact. Therefore, epidemiological analysis of infection clusters in human households is of key importance. Infection clusters may arise from transmission events from (i the animal reservoir, (ii humans who were infected by animals (primary human-to-human transmission, or (iii humans who were infected by humans (secondary human-to-human transmission. Here we propose a method of analysing household infection data to detect changes in the transmissibility of avian influenza viruses in humans at an early stage. The method is applied to an outbreak of H7N7 avian influenza virus in The Netherlands that was the cause of more than 30 human-to-human transmission events. The analyses indicate that secondary human-to-human transmission is plausible for the Dutch household infection data. Based on the estimates of the within-household transmission parameters, we evaluate the effectiveness of antiviral prophylaxis, and conclude that it is unlikely that all household infections can be prevented with current antiviral drugs. We discuss the applicability of our method for the detection of emerging human-to-human transmission of avian influenza viruses in particular, and for the analysis of within-household infection data in general.

  18. Evaluation of Amplified Fragment Length Polymorphism for Differentiation of Avian Mycoplasma Species

    OpenAIRE

    Hong, Y; Garcia, M.; Levisohn, S; Lysnyansky, I.; Leiting, V.; Savelkoul, P. H. M.; Kleven, S. H.

    2005-01-01

    Amplified fragment length polymorphism (AFLP) was used for typing avian mycoplasma species. Forty-four avian mycoplasma strains were successfully typed into eight distinct groups, with each representing a different species. Homology of AFLP patterns of 35% or less was used as a cutoff value to differentiate avian mycoplasma strains into different species.

  19. H5N1 Avian Flu (H5N1 Bird Flu)

    Science.gov (United States)

    ... Swine Flu H5N1 - Avian/Bird Flu H5N1 Avian Flu - H5N1 Bird Flu H5N1 is a highly pathogenic avian (bird) flu ... WhiteHouse.gov USA.gov GobiernoUSA.gov BusinessUSA.gov Flu Basics Symptoms (CDC) Prevention (CDC) Treatment (CDC) Vaccination ( ...

  20. Avian Blood-Vessel Formation in Space

    Science.gov (United States)

    Lelkes, Peter I.

    1999-01-01

    Based on previous studies, we hypothesized that the developmental anomalies observed in the past might be related to or caused by delayed or improper vascular development. The objective of our research is to test the hypothesis that exposure to microgravity during space flight cause delayed or improper vascular development during embryogenesis. The effects of microgravity on the time course and extent of avian blood-vessel formation are assessed using two models, one for angiogenesis and one for vasculogenesis. The methodological approach is dictated by the constraints of the tissue preservation method used in space. Thus, both in the chorioallantoic membrane (CAM) and in the adrenal, we will evaluate microscopically the vascular architecture and immunostain endothelial cells with specific antibodies (anti- vWF and QH1). The extent of ECM protein deposition will be assessed by immunohistochemistry and correlated with the degree of vascularization, using computer-based image analysis. Also, the cellular source for ECM proteins will be assessed by in situ hybridization.

  1. Scaling of avian primary feather length.

    Directory of Open Access Journals (Sweden)

    Robert L Nudds

    Full Text Available The evolution of the avian wing has long fascinated biologists, yet almost no work includes the length of primary feathers in consideration of overall wing length variation. Here we show that the length of the longest primary feather (f(prim contributing to overall wing length scales with negative allometry against total arm (ta = humerus+ulna+manus. The scaling exponent varied slightly, although not significantly so, depending on whether a species level analysis was used or phylogeny was controlled for using independent contrasts: f(prim is proportional to ta(0.78-0.82. The scaling exponent was not significantly different from that predicted (0.86 by earlier work. It appears that there is a general trend for the primary feathers of birds to contribute proportionally less, and ta proportionally more, to overall wingspan as this dimension increases. Wingspan in birds is constrained close to mass (M(1/3 because of optimisation for lift production, which limits opportunities for exterior morphological change. Within the wing, variations in underlying bone and feather lengths nevertheless may, in altering the joint positions, permit a range of different flight styles by facilitating variation in upstroke kinematics.

  2. Research progress in avian dispersal behavior

    Institute of Scientific and Technical Information of China (English)

    Yang LIU; Zhengwang ZHANG

    2008-01-01

    Dispersal, defined as a linear spreading move-ment of individuals away from others of the population is a fundamental characteristic of organisms in nature. Dispersal is a central concept in ecological, behavioral and evolutionary studies, driven by different forces such as avoidance of inbreeding depression, density-dependent competition and the need to change breeding locations. By effective dispersal, organisms can enlarge their geo-graphic range and adjust the dynamic, sex ratio and gen-etic compositions of a population. Birds are one of the groups that are studied intensively by human beings. Due to their diurnal habits, diverse life history strategies and complex movement, birds are also ideal models for the study of dispersal behaviors. Certain topics of avian dispersal including sex-biased, asymmetric dispersal caused by differences in body conditions, dispersal pro-cesses, habitat selection and long distance dispersal are discussed here. Bird-ringing or marking, radio-telemetry and genetic markers are useful tools widely applied in dispersal studies. There are three major challenges regard-ing theoretical study and methodology research of dis-persal: (1) improvement in research methodology is needed, (2) more in-depth theoretical research is neces-sary, and (3) application of theoretical research into the conservation efforts for threatened birds and the manage-ment of their habitats should be carried out immediately.

  3. Comparison of lead residues among avian bones

    International Nuclear Information System (INIS)

    To determine if significant differences exist in lead (Pb) accumulation in different bones, especially those most often used for bone-Pb studies in wildlife, we compared Pb concentrations in radius, ulna, humerus, femur, and tibia of Common Eider (Somateria mollissima); and radius/ulna (combined), femur, and tibia of American Woodcock (Scolopax minor). There were no significant differences in bone-Pb concentrations among woodcock bones over a wide range of Pb concentrations (3-311 μg/g). In eider, where bone-Pb concentrations were low (<10 μg/g), leg bones had significantly higher Pb concentrations (approximately 30-40%) than wing bones from the same individuals. The variation among individual birds was greater than the variation among different bones within a bird. Based on our findings, we conclude that one type of bone may be substituted for another in bone-Pb studies although the same bone type should be analyzed for all birds within a study, whenever possible. - Variability in Pb concentrations among avian bones

  4. Worldwide phylogenetic relationship of avian poxviruses

    Science.gov (United States)

    Gyuranecz, Miklós; Foster, Jeffrey T.; Dán, Ádám; Ip, Hon S.; Egstad, Kristina F.; Parker, Patricia G.; Higashiguchi, Jenni M.; Skinner, Michael A.; Höfle, Ursula; Kreizinger, Zsuzsa; Dorrestein, Gerry M.; Solt, Szabolcs; Sós, Endre; Kim, Young Jun; Uhart, Marcela; Pereda, Ariel; González-Hein, Gisela; Hidalgo, Hector; Blanco, Juan-Manuel; Erdélyi, Károly

    2013-01-01

    Poxvirus infections have been found in 230 species of wild and domestic birds worldwide in both terrestrial and marine environments. This ubiquity raises the question of how infection has been transmitted and globally dispersed. We present a comprehensive global phylogeny of 111 novel poxvirus isolates in addition to all available sequences from GenBank. Phylogenetic analysis of Avipoxvirus genus has traditionally relied on one gene region (4b core protein). In this study we have expanded the analyses to include a second locus (DNA polymerase gene), allowing for a more robust phylogenetic framework, finer genetic resolution within specific groups and the detection of potential recombination. Our phylogenetic results reveal several major features of avipoxvirus evolution and ecology and propose an updated avipoxvirus taxonomy, including three novel subclades. The characterization of poxviruses from 57 species of birds in this study extends the current knowledge of their host range and provides the first evidence of the phylogenetic effect of genetic recombination of avipoxviruses. The repeated occurrence of avian family or order-specific grouping within certain clades (e.g. starling poxvirus, falcon poxvirus, raptor poxvirus, etc.) indicates a marked role of host adaptation, while the sharing of poxvirus species within prey-predator systems emphasizes the capacity for cross-species infection and limited host adaptation. Our study provides a broad and comprehensive phylogenetic analysis of the Avipoxvirus genus, an ecologically and environmentally important viral group, to formulate a genome sequencing strategy that will clarify avipoxvirus taxonomy.

  5. What's missing from avian global diversification analyses?

    Science.gov (United States)

    Reddy, Sushma

    2014-08-01

    The accumulation of vast numbers of molecular phylogenetic studies has contributed to huge knowledge gains in the evolutionary history of birds. This permits subsequent analyses of avian diversity, such as how and why diversification varies across the globe and among taxonomic groups. However, available genetic data for these meta-analyses are unevenly distributed across different geographic regions and taxonomic groups. To comprehend the impact of this variation on the interpretation of global diversity patterns, I examined the availability of genetic data for possible biases in geographic and taxonomic sampling of birds. I identified three main disparities of sampling that are geographically associated with latitude (temperate, tropical), hemispheres (East, West), and range size. Tropical regions, which host the vast majority of species, are substantially less studied. Moreover, Eastern regions, such as the Old World Tropics and Australasia, stand out as being disproportionately undersampled, with up to half of communities not being represented in recent studies. In terms of taxonomic discrepancies, a majority of genetically undersampled clades are exclusively found in tropical regions. My analysis identifies several disparities in the key regions of interest of global diversity analyses. Differential sampling can have considerable impacts on these global comparisons and call into question recent interpretations of latitudinal or hemispheric differences of diversification rates. Moreover, this review pinpoints understudied regions whose biota are in critical need of modern systematic analyses.

  6. Multi-scale occupancy approach to estimate Toxoplasma gondii prevalence and detection probability in tissues: an application and guide for field sampling.

    Science.gov (United States)

    Elmore, Stacey A; Huyvaert, Kathryn P; Bailey, Larissa L; Iqbal, Asma; Su, Chunlei; Dixon, Brent R; Alisauskas, Ray T; Gajadhar, Alvin A; Jenkins, Emily J

    2016-08-01

    Increasingly, birds are recognised as important hosts for the ubiquitous parasite Toxoplasma gondii, although little experimental evidence exists to determine which tissues should be tested to maximise the detection probability of T. gondii. Also, Arctic-nesting geese are suspected to be important sources of T. gondii in terrestrial Arctic ecosystems, but the parasite has not previously been reported in the tissues of these geese. Using a domestic goose model, we applied a multi-scale occupancy framework to demonstrate that the probability of detection of T. gondii was highest in the brain (0.689, 95% confidence interval=0.486, 0.839) and the heart (0.809, 95% confidence interval=0.693, 0.888). Inoculated geese had an estimated T. gondii infection probability of 0.849, (95% confidence interval=0.643, 0.946), highlighting uncertainty in the system, even under experimental conditions. Guided by these results, we tested the brains and hearts of wild Ross's Geese (Chen rossii, n=50) and Lesser Snow Geese (Chen caerulescens, n=50) from Karrak Lake, Nunavut, Canada. We detected 51 suspected positive tissue samples from 33 wild geese using real-time PCR with melt-curve analysis. The wild goose prevalence estimates generated by our multi-scale occupancy analysis were higher than the naïve estimates of prevalence, indicating that multiple PCR repetitions on the same organs and testing more than one organ could improve T. gondii detection. Genetic characterisation revealed Type III T. gondii alleles in six wild geese and Sarcocystis spp. in 25 samples. Our study demonstrates that Arctic nesting geese are capable of harbouring T. gondii in their tissues and could transport the parasite from their southern overwintering grounds into the Arctic region. We demonstrate how a multi-scale occupancy framework can be used in a domestic animal model to guide resource-limited sample collection and tissue analysis in wildlife. Secondly, we confirm the value of traditional occupancy in

  7. Transport of polar molecules by an alternating gradient guide

    OpenAIRE

    Wall, T. E.; Armitage, S; Hudson, J. J.; Sauer, B. E.; Dyne, J. M.; Hinds, E. A.; Tarbutt, M.R.

    2009-01-01

    An alternating gradient electric guide provides a way to transport a wide variety of polar molecules, including those in high-field seeking states. We investigate the motion of polar molecules in such a guide by measuring the transmission of CaF molecules in their high-field seeking ground state, with the guide operating at a variety of switching frequencies and voltages. We model the guide using analytical and numerical techniques and compare the predictions of these models to the experiment...

  8. Postmortem procedure and diagnostic avian pathology

    Directory of Open Access Journals (Sweden)

    A. Bello

    2012-11-01

    Full Text Available This review paper will highlight the basic systematic procedures involve from submission of carcass for the investigation of disease to diagnosis and will serve as a guide to veterinarians (anatomist and pathologist on postmortem proceedures in clinical practice.

  9. Examining the Spectral Separability of Prosopis glandulosa from Co-Existent Species Using Field Spectral Measurement and Guided Regularized Random Forest

    Directory of Open Access Journals (Sweden)

    Nyasha Mureriwa

    2016-02-01

    Full Text Available The invasive taxa of Prosopis is rated the world’s top 100 unwanted species, and a lack of spatial data about the invasion dynamics has made the current control and monitoring methods unsuccessful. This study thus tests the use of in situ spectroscopy data with a newly-developed algorithm, guided regularized random forest (GRRF, to spectrally discriminate Prosopis from coexistent acacia species (Acacia karroo, Acacia mellifera and Ziziphus mucronata in the arid environment of South Africa. Results show that GRRF was able to reduce the high dimensionality of the spectroscopy data and select key wavelengths (n = 11 for discriminating amongst the species. These wavelengths are located at 356.3 nm, 468.5 nm, 531.1 nm, 665.2 nm, 1262.3 nm, 1354.1 nm, 1361.7 nm, 1376.9 nm, 1407.1 nm, 1410.9 nm and 1414.6 nm. The use of these selected wavelengths increases the overall classification accuracy from 79.19% and a Kappa value of 0.7201 when using all wavelengths to 88.59% and a Kappa of 0.8524 when the selected wavelengths were used. Based on our relatively high accuracies and ease of use, it is worth considering the GRRF method for reducing the high dimensionality of spectroscopy data. However, this assertion should receive considerable additional testing and comparison before it is accepted as a substitute for reliable high dimensionality reduction.

  10. Using models to guide field experiments: a priori predictions for the CO2 response of a nutrient- and water-limited native Eucalypt woodland.

    Science.gov (United States)

    Medlyn, Belinda E; De Kauwe, Martin G; Zaehle, Sönke; Walker, Anthony P; Duursma, Remko A; Luus, Kristina; Mishurov, Mikhail; Pak, Bernard; Smith, Benjamin; Wang, Ying-Ping; Yang, Xiaojuan; Crous, Kristine Y; Drake, John E; Gimeno, Teresa E; Macdonald, Catriona A; Norby, Richard J; Power, Sally A; Tjoelker, Mark G; Ellsworth, David S

    2016-08-01

    The response of terrestrial ecosystems to rising atmospheric CO2 concentration (Ca ), particularly under nutrient-limited conditions, is a major uncertainty in Earth System models. The Eucalyptus Free-Air CO2 Enrichment (EucFACE) experiment, recently established in a nutrient- and water-limited woodland presents a unique opportunity to address this uncertainty, but can best do so if key model uncertainties have been identified in advance. We applied seven vegetation models, which have previously been comprehensively assessed against earlier forest FACE experiments, to simulate a priori possible outcomes from EucFACE. Our goals were to provide quantitative projections against which to evaluate data as they are collected, and to identify key measurements that should be made in the experiment to allow discrimination among alternative model assumptions in a postexperiment model intercomparison. Simulated responses of annual net primary productivity (NPP) to elevated Ca ranged from 0.5 to 25% across models. The simulated reduction of NPP during a low-rainfall year also varied widely, from 24 to 70%. Key processes where assumptions caused disagreement among models included nutrient limitations to growth; feedbacks to nutrient uptake; autotrophic respiration; and the impact of low soil moisture availability on plant processes. Knowledge of the causes of variation among models is now guiding data collection in the experiment, with the expectation that the experimental data can optimally inform future model improvements. PMID:26946185

  11. Dynamics of Vector-Host Interactions in Avian Communities in Four Eastern Equine Encephalitis Virus Foci in the Northeastern U.S.

    Directory of Open Access Journals (Sweden)

    Goudarz Molaei

    2016-01-01

    Full Text Available Eastern equine encephalitis (EEE virus (Togaviridae, Alphavirus is a highly pathogenic mosquito-borne zoonosis that is responsible for occasional outbreaks of severe disease in humans and equines, resulting in high mortality and neurological impairment in most survivors. In the past, human disease outbreaks in the northeastern U.S. have occurred intermittently with no apparent pattern; however, during the last decade we have witnessed recurring annual emergence where EEE virus activity had been historically rare, and expansion into northern New England where the virus had been previously unknown. In the northeastern U.S., EEE virus is maintained in an enzootic cycle involving the ornithophagic mosquito, Culiseta melanura, and wild passerine (perching birds in freshwater hardwood swamps. However, the identity of key avian species that serve as principal virus reservoir and amplification hosts has not been established. The efficiency with which pathogen transmission occurs within an avian community is largely determined by the relative reservoir competence of each species and by ecological factors that influence contact rates between these avian hosts and mosquito vectors.Contacts between vector mosquitoes and potential avian hosts may be directly quantified by analyzing the blood meal contents of field-collected specimens. We used PCR-based molecular methods and direct sequencing of the mitochondrial cytochrome b gene for profiling of blood meals in Cs. melanura, in an effort to quantify its feeding behavior on specific vertebrate hosts, and to infer epidemiologic implications in four historic EEE virus foci in the northeastern U.S. Avian point count surveys were conducted to determine spatiotemporal host community composition. Of 1,127 blood meals successfully identified to species level, >99% of blood meals were from 65 avian hosts in 27 families and 11 orders, and only seven were from mammalian hosts representing three species. We developed an

  12. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards: November 2012 - October 2013

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, W.

    2015-02-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  13. Unix Application Migration Guide

    CERN Document Server

    Microsoft. Redmond

    2003-01-01

    Drawing on the experience of Microsoft consultants working in the field, as well as external organizations that have migrated from UNIX to Microsoft® Windows®, this guide offers practical, prescriptive guidance on the issues you are likely to face when porting existing UNIX applications to the Windows operating system environment. Senior IT decision makers, network managers, and operations managers will get real-world guidance and best practices on planning and implementation issues to understand the different methods through which migration or co-existence can be accomplished. Also detailing

  14. Optimized polypeptide for a subunit vaccine against avian reovirus.

    Science.gov (United States)

    Goldenberg, Dana; Lublin, Avishai; Rosenbluth, Ezra; Heller, E Dan; Pitcovski, Jacob

    2016-06-01

    Avian reovirus (ARV) is a disease-causing agent. The disease is prevented by vaccination with a genotype-specific vaccine while many variants of ARV exist in the field worldwide. Production of new attenuated vaccines is a long-term process and in the case of fast-mutating viruses, an impractical one. In the era of molecular biology, vaccines may be produced by using only the relevant protein for induction of neutralizing antibodies, enabling fast adjustment to the emergence of new genetic strains. Sigma C (SC) protein of ARV is a homotrimer that facilitates host-cell attachment and induce the production and secretion of neutralizing antibodies. The aim of this study was to identify the region of SC that will elicit a protective immune response. Full-length (residues 1-326) and two partial fragments of SC (residues 122-326 and 192-326) were produced in Escherichia coli. The SC fragment of residues 122-326 include the globular head, shaft and hinge domains, while eliminating intra-capsular region. This fragment induces significantly higher levels of anti-ARV antibodies than the shorter fragment or full length SC, which neutralized embryos infection by the virulent strain to a higher extent compared with the antibodies produced in response to the whole virus vaccine. Residues 122-326 fragment is assumed to be folded correctly, exposing linear as well as conformational epitopes that are identical to those of the native protein, while possibly excluding suppressor sequences. The results of this study may serve for the development of a recombinant subunit vaccine for ARV. PMID:27155492

  15. Low field permanent magnet MRI guided focused ultrasound system for tumor ablation%低场永磁MRI导引聚焦超声肿瘤消融系统的研究

    Institute of Scientific and Technical Information of China (English)

    李大为

    2014-01-01

    This paper discusses a low field permanent magnet MRI guided HIFU system which made up the two sys-tems of MRI and HIFU into a whole system. The MRI magnet was designed to U-shaped, so that HIFU treatment head could be placed above the opening of the MRI magnet. The magnetic compatibility, fast magnetic resonance im-aging, temperature measurement by MRI, phased array transducers, HIFU treatment method etc are also discussed. The result shows that guided by low field permanent magnet MRI, the system could achieve all the designed functions. The advantages of the system are that the positioning image is much clearer than that of the ultrasound scanner of pre-vious generation, and improves the practicability greatly.%研究了低场永磁磁共振(Magnetic Resonance Imaging, MRI)导引的高强度聚焦超声(High Intensity Focused Ul-trasound, HIFU)系统,使两者融合为一体。把磁共振的磁体设计为U字形,这样HIFU治疗头就可以放置于磁共振开口的上方;同时,在磁兼容、磁共振的快速成像、磁共振的测温、相控阵换能器、HIFU的治疗计划等方面做了一些研究。研究结果表明,在低场永磁的磁共振导引下,可以实现系统的所有设计功能,系统定位的图像比上一代 B 超导引的HIFU清晰,提高了实用性。

  16. Low field permanent magnet MRI guided focused ultrasound system for tumor ablation%低场永磁MRI导引聚焦超声肿瘤消融系统的研究

    Institute of Scientific and Technical Information of China (English)

    李大为

    2014-01-01

    研究了低场永磁磁共振(Magnetic Resonance Imaging, MRI)导引的高强度聚焦超声(High Intensity Focused Ul-trasound, HIFU)系统,使两者融合为一体。把磁共振的磁体设计为U字形,这样HIFU治疗头就可以放置于磁共振开口的上方;同时,在磁兼容、磁共振的快速成像、磁共振的测温、相控阵换能器、HIFU的治疗计划等方面做了一些研究。研究结果表明,在低场永磁的磁共振导引下,可以实现系统的所有设计功能,系统定位的图像比上一代 B 超导引的HIFU清晰,提高了实用性。%This paper discusses a low field permanent magnet MRI guided HIFU system which made up the two sys-tems of MRI and HIFU into a whole system. The MRI magnet was designed to U-shaped, so that HIFU treatment head could be placed above the opening of the MRI magnet. The magnetic compatibility, fast magnetic resonance im-aging, temperature measurement by MRI, phased array transducers, HIFU treatment method etc are also discussed. The result shows that guided by low field permanent magnet MRI, the system could achieve all the designed functions. The advantages of the system are that the positioning image is much clearer than that of the ultrasound scanner of pre-vious generation, and improves the practicability greatly.

  17. The Evaluation of Guiding Private Capital into Urban Infrastructure Construction Field Policy%民间资本进入城镇基础设施建设领域政策评估

    Institute of Scientific and Technical Information of China (English)

    翁辰宇

    2012-01-01

    我国民间资本具有极大的存量。近年来,国家出台一系列政策积极引导民间资本进入城镇基础设施建设领域,因此政策评估的重点是考察其目标的实现程度和对社会的影响。费希尔政策评估框架有效整合了事实和价值两个层面的评估,以该模式为框架对民间资本投资城镇基础设施建设政策做出多层次的评估,不仅有助于分析政策的各种效果和意义,也为推进我国公共政策评估提供了新的思路。%China has a great amount of private capital,and in recent years,governments stage a series of policies actively to guide private capital into urban infrastructure construction field, thus the target achieving degree and social influence is the key of policy eval- uation. The Frank Fisher policy evaluating framework effectively integrates the fact and value evaluation. We use this framework to make multi-level evaluating of guiding private capital into urban infrastructure construction field pohcy ,not only contribute to analyzing all sorts of effect and significance, but also provides a new concept to promoting public policy evaluation efficiency.

  18. Antigenic properties of avian hepatitis E virus capsid protein.

    Science.gov (United States)

    Zhao, Qin; Syed, Shahid Faraz; Zhou, En-Min

    2015-10-22

    Avian hepatitis E virus (HEV) is the main causative agent of big liver and spleen disease and hepatitis-splenomegaly syndrome in chickens, and is genetically and antigenically related to mammalian HEVs. HEV capsid protein contains immunodominant epitopes and induces a protective humoral immune response. A better understanding of the antigenic composition of this protein is critically important for the development of effective vaccine and sensitive and specific serological assays. To date, six linear antigenic domains (I-VI) have been characterized in avian HEV capsid protein and analyzed for their applications in the serological diagnosis and vaccine design. Domains I and V induce strong immune response in chickens and are common to avian, human, and swine HEVs, indicating that the shared epitopes hampering differential diagnosis of avian HEV infection. Domains III and IV are not immunodominant and elicit a weak immune response. Domain VI, located in the N-terminal region of the capsid protein, can also trigger an intense immune response, but the anti-domain VI antibodies are transient. The protection analysis showed that the truncated capsid protein containing the C-terminal 268 amino acid residues expressed by the bacterial system can provide protective immunity against avian HEV infection in chickens. However, the synthetic peptides incorporating the different linear antigenic domains (I-VI) and epitopes are non-protective. The antigenic composition of avian HEV capsid protein is altogether complex. To develop an effective vaccine and accurate serological diagnostic methods, more conformational antigenic domains or epitopes are to be characterized in detail. PMID:26340899

  19. Absence of avian pox in wild turkeys in central Mississippi.

    Science.gov (United States)

    Couvillion, C E; Stacey, L M; Hurst, G A

    1991-07-01

    Eastern wild turkeys (Meleagris gallopavo silvestris) (n = 1,023), obtained during winter, spring, and summer from 1983 to 1988 on Tallahala Wildlife Management Area (TWMA) (Jasper County, Mississippi, USA) were examined for avian pox lesions. Domestic turkey poults (n = 152) maintained on the area for 1 to 2 wk periods from 1987 to 1989 also were examined. Neither wild nor domestic birds showed gross evidence of pox virus infection. This study indicated that avian pox was not endemic in wild turkeys at TWMA.

  20. Emergence of Fatal Avian Influenza in New England Harbor Seals

    OpenAIRE

    Anthony, S. J.; St. Leger, J. A.; Pugliares, K.; Ip, H S; Chan, J. M.; Carpenter, Z. W.; Navarrete-Macias, I.; Sanchez-Leon, M.; Saliki, J T; Pedersen, J; Karesh, W; Daszak, P; Rabadan, R.; Rowles, T.; Lipkin, W. I.

    2012-01-01

    ABSTRACT From September to December 2011, 162 New England harbor seals died in an outbreak of pneumonia. Sequence analysis of postmortem samples revealed the presence of an avian H3N8 influenza A virus, similar to a virus circulating in North American waterfowl since at least 2002 but with mutations that indicate recent adaption to mammalian hosts. These include a D701N mutation in the viral PB2 protein, previously reported in highly pathogenic H5N1 avian influenza viruses infecting people. L...

  1. Avian Influenza: a global threat needing a global solution

    OpenAIRE

    Koh GCH; Wong TY; Cheong SK; Koh DSQ

    2008-01-01

    Abstract There have been three influenza pandemics since the 1900s, of which the 1919–1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI) is endemic in Asia as a result of unre...

  2. The challenges of avian influenza virus: mechanism, epidemiology and control

    Institute of Scientific and Technical Information of China (English)

    George F. GAO; Pang-Chui SHAW

    2009-01-01

    @@ Early 2009, eight human infection cases of H5N1 highly pathogenic avian influenza (HPAI) virus, with 5 death cases, were reported in China. This again made the world alert on a possible pandemic worldwide, probably caused by avian-origin influenza virus. Again H5N1 is in the spotlight of the world, not only for the scientists but also for the ordinary people. How much do we know about this virus? Where will this virus go and where did it come? Can we avoid a possible pandemic of influenza? Will the human beings conquer this devastating agent? Obviously we can list more questions than we know the answers.

  3. Microbes of the avian cecum: types present and substrates utilized.

    Science.gov (United States)

    Mead, G C

    1989-01-01

    This paper discusses the types and properties of microorganisms found in avian ceca, with special reference to the chicken. Microbial activity in the cecum is primarily fermentative, but there has been little evidence of cellulose fermentation, and the predominant bacterial types are relatively inactive against other high-molecular-weight compounds of dietary origin. In all avian species examined, the consistent presence of large populations of uric acid-degrading bacteria supports the view that microbial populations in the ceca permit reabsorption of water and possibly nonprotein nitrogen from the backflow of urine. These capabilities may be of particular importance to wild birds under conditions of water and food deprivation.

  4. Electronic Technology. Post Secondary Curriculum Guide.

    Science.gov (United States)

    Sappe, Hoyt; And Others

    This curriculum guide provides a model for a postsecondary electronic technology program. It is divided into 10 sections. Section 1 overviews the philosophy, purpose, and goals for vocational education in Georgia. Contents of section 2 include a definition of the guide's purpose and program objective. Section 3 describes the occupational field,…

  5. Multimode interferometer for guided matter waves.

    Science.gov (United States)

    Andersson, Erika; Calarco, Tommaso; Folman, Ron; Andersson, Mauritz; Hessmo, Björn; Schmiedmayer, Jörg

    2002-03-11

    Atoms can be trapped and guided with electromagnetic fields, using nanofabricated structures. We describe the fundamental features of an interferometer for guided matter waves, built of two combined Y-shaped beam splitters. We find that such a device is expected to exhibit high contrast fringes even in a multimode regime, analogous to a white light interferometer.

  6. Avian Influenza: Myth or Mass Murder?

    Directory of Open Access Journals (Sweden)

    Carol Louie

    2005-01-01

    Full Text Available The purpose of the present article was to determine whether avian influenza (AI is capable of causing a pandemic. Using research from a variety of medical journals, books and texts, the present paper evaluates the probability of the AI virus becoming sufficiently virulent to pose a global threat. Previous influenza A pandemics from the past century are reviewed, focusing on the mortality rate and the qualities of the virus that distinguish it from other viruses. Each of the influenza A viruses reviewed were classified as pandemic because they met three key criteria: first, the viruses were highly pathogenic within the human population; second, the viruses were easily transmissible from person to person; and finally, the viruses were novel, such that a large proportion of the population was susceptible to infection. Information about the H5N1 subtype of AI has also been critically assessed. Evidence suggests that this AI subtype is both novel and highly pathogenic. The mortality rate from epidemics in Thailand in 2004 was as high as 66%. Clearly, this virus is aggressive. It causes a high death rate, proving that humans have a low immunity to the disease. To date, there has been little evidence to suggest that AI can spread among humans. There have been cases where the virus has transferred from birds to humans, in settings such as farms or open markets with live animal vending. If AI were to undergo a genetic reassortment that allowed itself to transmit easily from person to person, then a serious pandemic could ensue, resulting in high morbidity and mortality. Experts at the World Health Organization and the United States Centers for Disease Control and Prevention agree that AI has the potential to undergo an antigenic shift, thus triggering the next pandemic.

  7. Role of estrogen in avian osteoporosis.

    Science.gov (United States)

    Beck, M M; Hansen, K K

    2004-02-01

    One of the difficulties associated with commercial layer production is the development of osteoporosis in hens late in the production cycle. In light of this fact and because of hens' unique requirements for Ca, many studies have focused on the regulation of Ca and the role of estrogen in this process. The time course of estrogen synthesis over the productive life of hens has been well documented; increased circulating estrogen accompanies the onset of sexual maturity while decreases signal a decline in egg production prior to a molt. Numbers of estrogen receptors decrease with age in numerous tissues. The parallel changes in calcium-regulating proteins, primarily Calbindin D28K, and in the ability of duodenal cells to transport Ca, are thought to occur as a result of the changes in estrogen, and are also reversible by the molt process. In addition to the traditional model of estrogen action, evidence now exists for a possible nongenomic action of estrogen via membrane-bound receptors, demonstrated by extremely rapid surges of ionized Ca in chicken granulosa cells in response to 17beta-estradiol. Estrogen receptors have also been discovered in duodenal tissue, and tamoxifen, which binds to the estrogen receptor, has been shown to cause a rapid increase in Ca transport in the duodenum. In addition, recent evidence also suggests that mineralization of bone per se may not explain entirely the etiology of osteoporosis in the hen but that changes in the collagen matrix may contribute through decreases in bone elasticity. Taken together, these studies suggest that changes in estrogen synthesis and estrogen receptor populations may underlie the age-related changes in avian bone. As with postmenopausal women, dietary Ca and vitamin D are of limited benefit as remedies for osteoporosis in the hen. PMID:14979570

  8. The Numerical Computation of Coupled Problem for the Electromagnetic and Thermal Field within the Hardening Processes of Valve Guides Through Electromagnetic Induction

    Directory of Open Access Journals (Sweden)

    ARION Mircea

    2012-10-01

    Full Text Available This paper presents the numerical modeling of the coupled electromagnetic and thermal field question within the induction hardening of inner cylindrical surface. In order to solve the coupled field problem accomplished into induction equipments during hardening processes, the numerical computation has been performed in two-dimension (2D using the finite element methods (F.E.M.. Theobtained results provide usefull information regarding the halffinished product heating during hardening process, the over heating of thin layers, the geometrical configuration of the inductor as well as the technological requirements correlated with electricalparameters which represents an active tool to setup the induction heating equipment in order to get the best results during hardening process.

  9. An Extended action for the effective field theory of dark energy: a stability analysis and a complete guide to the mapping at the basis of EFTCAMB

    OpenAIRE

    Frusciante, Noemi; Papadomanolakis, Georgios; Silvestri, Alessandra

    2016-01-01

    We present a generalization of the effective field theory (EFT) formalism for dark energy and modified gravity models to include operators with higher order spatial derivatives. This allows the extension of the EFT framework to a wider class of gravity theories such as Horava gravity. We present the corresponding extended action, both in the EFT and the Arnowitt-Deser-Misner (ADM) formalism, and proceed to work out a convenient mapping between the two, providing a self contained and general p...

  10. Emergency Medical Services Program Guide.

    Science.gov (United States)

    Georgia Univ., Athens. Dept. of Vocational Education.

    This program guide contains the standard emergency medical services curriculum for technical institutes in Georgia. The curriculum encompasses the minimum competencies required for entry-level workers in the emergency medical services field, and includes job skills in six emergency medical services divisions outlined in the national curriculum:…

  11. Inactivated vaccine with adjuvants consisting of pattern recognition receptor agonists confers protection against avian influenza viruses in chickens.

    Science.gov (United States)

    Tang, Yinghua; Lu, Jihu; Wu, Peipei; Liu, Zhenxing; Tian, Zhen; Zha, Guofei; Chen, Hui; Wang, Qiaochu; Wang, Qiaoxiu; Hou, Fengxiang; Kang, Sang-Moo; Hou, Jibo

    2014-08-01

    Use of adjuvant containing pathogen pattern recognition receptor agonists is one of the effective strategies to enhance the efficacy of licensed vaccines. In this study, we investigated the efficacy of avian influenza vaccines containing an adjuvant (CVCVA5) which was composed of polyriboinosinic polyribocytidylic, resiquimod, imiquimod, muramyl dipeptide and levomisole. Avian influenza vaccines adjuvanted with CVCVA5 were found to induce significantly higher titers of hemagglutiniton inhibition antibodies (P≤0.01) than those of commercial vaccines at 2-, 3- and 4-week post vaccination in both specific pathogen free (SPF) chickens and field application. Furthermore, virus shedding was reduced in SPF chickens immunized with H9-CVCVA5 vaccine after H9 subtype heterologous virus challenge. The ratios of both CD3(+)CD4(+) and CD3(+)CD8(+) lymphocytes were slowly elevated in chickens immunized with H9-CVCVA5 vaccine. Lymphocytes adoptive transfer study indicates that CD8(+) T lymphocyte subpopulation might have contributed to improved protection against heterologous virus challenge. Results of this study suggest that the adjuvant CVCVA5 was capable of enhancing the potency of existing avian influenza vaccines by increasing humoral and cellular immune response.

  12. Flocking and self-defense: experiments and simulations of avian mobbing

    Science.gov (United States)

    Kane, Suzanne Amador

    2011-03-01

    We have performed motion capture studies in the field of avian mobbing, in which flocks of prey birds harass predatory birds. Our empirical studies cover both field observations of mobbing occurring in mid-air, where both predator and prey are in flight, and an experimental system using actual prey birds and simulated predator ``perch and wait'' strategies. To model our results and establish the effectiveness of mobbing flight paths at minimizing risk of capture while optimizing predator harassment, we have performed computer simulations using the actual measured trajectories of mobbing prey birds combined with model predator trajectories. To accurately simulate predator motion, we also measured raptor acceleration and flight dynamics, well as prey-pursuit strategies. These experiments and theoretical studies were all performed with undergraduate research assistants in a liberal arts college setting. This work illustrates how biological physics provides undergraduate research projects well-suited to the abilities of physics majors with interdisciplinary science interests and diverse backgrounds.

  13. Multivalent HA DNA vaccination protects against highly pathogenic H5N1 avian influenza infection in chickens and mice.

    Directory of Open Access Journals (Sweden)

    Srinivas Rao

    Full Text Available BACKGROUND: Sustained outbreaks of highly pathogenic avian influenza (HPAI H5N1 in avian species increase the risk of reassortment and adaptation to humans. The ability to contain its spread in chickens would reduce this threat and help maintain the capacity for egg-based vaccine production. While vaccines offer the potential to control avian disease, a major concern of current vaccines is their potency and inability to protect against evolving avian influenza viruses. METHODOLOGY / PRINCIPAL FINDINGS: The ability of DNA vaccines encoding hemagglutinin (HA proteins from different HPAI H5N1 serotypes was evaluated for its ability to elicit neutralizing antibodies and to protect against homologous and heterologous HPAI H5N1 strain challenge in mice and chickens after DNA immunization by needle and syringe or with a pressure injection device. These vaccines elicited antibodies that neutralized multiple strains of HPAI H5N1 when given in combinations containing up to 10 HAs. The response was dose-dependent, and breadth was determined by the choice of the influenza virus HA in the vaccine. Monovalent and trivalent HA vaccines were tested first in mice and conferred protection against lethal H5N1 A/Vietnam/1203/2004 challenge 68 weeks after vaccination. In chickens, protection was observed against heterologous strains of HPAI H5N1 after vaccination with a trivalent H5 serotype DNA vaccine with doses as low as 5 microg DNA given twice either by intramuscular needle injection or with a needle-free device. CONCLUSIONS/SIGNIFICANCE: DNA vaccines offer a generic approach to influenza virus immunization applicable to multiple animal species. In addition, the ability to substitute plasmids encoding different strains enables rapid adaptation of the vaccine to newly evolving field isolates.

  14. High resolution micro-XRF maps of iron oxides inside sensory dendrites of putative avian magnetoreceptors

    Energy Technology Data Exchange (ETDEWEB)

    Falkenberg, G; Fleissner, G E; Fleissner, G U E; Schuchardt, K [Institute of Cell Biology and Neurosciences, Goethe-University Frankfurt a. M. (Germany); Kuehbacher, M [Department of Molecular Trace Element Research in the Life Sciences, Helmholtz Centre Berlin for Materials and Energy, Berlin (Germany); Chalmin, E [ID21 ESRF, Grenoble (France); Janssens, K, E-mail: gerald.falkenberg@desy.d [Department of Chemistry, University Antwerp (Belgium)

    2009-09-01

    Iron mineral containing sensory dendrites in the inner lining of the upper beak of homing pigeons and various bird species are the first candidate structures for an avian magnetic field receptor. A new concept of magnetoreception is based on detailed ultra-structural optical and electron microscopy analyses in combination with synchrotron radiation microscopic X-ray fluorescence analysis (micro-XRF) and microscopic X-ray absorption near edge structures (micro-XANES). Several behavioral experiments and first mathematical simulations affirm our avian magnetoreceptor model. The iron minerals inside the dendrites are housed in three different subcellular compartments (bullets, platelets, vesicles), which could be clearly resolved and identified by electron microscopy on ultrathin sections. Micro-XRF and micro-XANES data obtained at HASYLAB beamline L added information about the elemental distribution and Fe speciation, but are averaged over the complete dendrite due to limited spatial resolution. Here we present recently performed micro-XRF maps with sub-micrometer resolution (ESRF ID21), which reveal for the first time subcellular structural information from almost bulk-like dendrite sample material. Due to the thickness of 30 {mu}m the microarchitecture of the dendrites can be considered as undisturbed and artefacts introduced by sectioning might be widely reduced.

  15. Honest signaling and oxidative stress: the special case of avian acoustic communication

    Directory of Open Access Journals (Sweden)

    Stefania eCasagrande

    2016-05-01

    Full Text Available Much research on animal communication has addressed how costs or constraints determined by the oxidative status of an individual can assure the honesty of visual signals, such as sexually selected color ornaments. However, acoustic communication has been largely overlooked in this respect. Here, we describe the few available studies that have considered the role of oxidative status in mediating vocal behavior in adult and nestling birds. Further, we discuss the theoretical principles of how the honesty of avian acoustic signals may be maintained by an organism’s oxidative status. We here distinguish between studies that considered songs and begging calls as indicators of oxidative status and studies where vocalizations were assumed to be the source of oxidative costs. We outline experimental and methodological issues related to the study of bird vocalizations and oxidative stress and describe opportunities for future work in this field of research. Investigating the interactions between acoustic signals and redox state may help address some unresolved questions in avian vocalization, thereby increasing our understanding of the evolutionary pressures shaping animal communication. Finally, we argue that it will be important to extend this line of research beyond birds and include other taxa as well.

  16. A model for avian magnetoreception by coupling magnetite-based mechanism with radical-pair-based mechanism

    CERN Document Server

    Lu, Yan

    2012-01-01

    Many species of animals have been testified to use the geomagnetic field for their navigation, but the biophysical mechanism of magnetoreception has remained enigmatic. This paper presents a biophysical model consisting of magnetite-based mechanism and radical-pair-based mechanism for the avian magnetoreception. The amplitude of resultant magnetic field outside the magnetic particles correspond to the geomagnetic field direction and effect the yield of singlet/triplet state products in the radical pair reactions, therefore the yield of singlet/triplet state products can connect with the geomagnetic field information for orientational detection by the proposed model. The resultant magnetic fields corresponds to two materials with different magnetic properties were analysed under different directions of the geomagnetic field. The results shown that the ferromagnetic particles in organisms could provide more significant change of singlet state products than that of superparamagnetic particles, and the period of ...

  17. U.S. Geological Survey science strategy for highly pathogenic avian influenza in wildlife and the environment (2016–2020)

    Science.gov (United States)

    Harris, M. Camille; Pearce, John M.; Prosser, Diann J.; White, C. LeAnn; Miles, A. Keith; Sleeman, Jonathan M.; Brand, Christopher J.; Cronin, James P.; De La Cruz, Susan; Densmore, Christine L.; Doyle, Thomas W.; Dusek, Robert J.; Fleskes, Joseph P.; Flint, Paul L.; Guala, Gerald F.; Hall, Jeffrey S.; Hubbard, Laura E.; Hunt, Randall J.; Ip, Hon S.; Katz, Rachel A.; Laurent, Kevin W.; Miller, Mark P.; Munn, Mark D.; Ramey, Andy M.; Richards, Kevin D.; Russell, Robin E.; Stokdyk, Joel P.; Takekawa, John Y.; Walsh, Daniel P.

    2016-08-18

    IntroductionThrough the Science Strategy for Highly Pathogenic Avian Influenza (HPAI) in Wildlife and the Environment, the USGS will assess avian influenza (AI) dynamics in an ecological context to inform decisions made by resource managers and policymakers from the local to national level. Through collection of unbiased scientific information on the ecology of AI viruses and wildlife hosts in a changing world, the U.S. Geological Survey (USGS) will enhance the development of AI forecasting tools and ensure this information is integrated with a quality decision process for managing HPAI.The overall goal of this USGS Science Strategy for HPAI in Wildlife and the Environment goes beyond document­ing the occurrence and distribution of AI viruses in wild birds. The USGS aims to understand the epidemiological processes and environmental factors that influence HPAI distribution and describe the mechanisms of transmission between wild birds and poultry. USGS scientists developed a conceptual model describing the process linking HPAI dispersal in wild waterfowl to the outbreaks in poul­try. This strategy focuses on five long-term science goals, which include:Science Goal 1—Augment the National HPAI Surveillance Plan;Science Goal 2—Determine mechanisms of HPAI disease spread in wildlife and the environment;Science Goal 3—Characterize HPAI viruses circulating in wildlife;Science Goal 4—Understand implications of avian ecol­ogy on HPAI spread; andScience Goal 5—Develop HPAI forecasting and decision-making tools.These goals will help define and describe the processes outlined in the conceptual model with the ultimate goal of facilitating biosecurity and minimizing transfer of diseases across the wildlife-poultry interface. The first four science goals are focused on scientific discovery and the fifth goal is application-based. Decision analyses in the fifth goal will guide prioritization of proposed actions in the first four goals.

  18. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Science.gov (United States)

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella... established by conducting five replicate titrations on a sample of the bacterial vaccine used. Only...

  19. Highly pathogenic avian influenza virus among wild birds in Mongolia

    Science.gov (United States)

    The central Asian country of Mongolia supports large populations of migratory water birds that migrate across much of Asia where highly pathogenic avian influenza (HPAI) virus subtype H5N1 is endemic. This, together with the near absence of domestic poultry, makes Mongolia an ideal location to unde...

  20. Scare of Avian Flu Revisits India: A Bumpy Road Ahead

    Directory of Open Access Journals (Sweden)

    Rajnish Kumar Rai

    2008-04-01

    Full Text Available With the threat of an avian flu pandemic once again looming over eastern India, issues regarding patents and affordability and accessibility of drugs have taken center stage. The key priority of India should be to remain prepared to address the public health crisis effectively, by stockpiling the drug tamiflu so that it can be easily distributed and administered to the needy.India had been confronted with a serious threat of avian flu in 2005-06, but past experience shows that, despite having some of the broadest and most comprehensive compulsory patent licensing laws, India's policymaking elite shied away from fully exploiting these legal 'flexibilities.' Fortunately, the danger of avian flu did not turn into a substantial public health crisis that year. Under this backdrop, this paper explores various ‘flexibilities’ available in the Indian patent law and suggests short term and long term strategies to effectively tackle the impending danger of an avian flu pandemic, and similar public health crises in future. This paper will discuss potential areas of conflict between the indigenous generic drug firms and the multi-national companies with respect to TRIPS compliance in the event that these flexibilities are exploited. This paper also highlights the administrative constraints and the economic viability of the compulsory licensing system. Finally, this paper shows how political will is often more critical than having well documented provisions in statute books to respond to such situations effectively.