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. Avian foods, foraging and habitat conservation in world rice fields

    Science.gov (United States)

    Stafford, J.D.; Kaminski, R.M.; Reinecke, K.J.

    2010-01-01

    Worldwide, rice (Oryza sativa) agriculture typically involves seasonal flooding and soil tillage, which provides a variety of microhabitats and potential food for birds. Water management in rice fields creates conditions ranging from saturated mud flats to shallow (water, thereby attracting different guilds of birds. Grain not collected during harvest (i.e. waste rice) is typically the most abundant potential food of birds in rice fields, with estimates of seed mass from North America ranging from 66672 kg/ha. Although initially abundant after harvest, waste rice availability can be temporally limited. Few abundance estimates for other foods, such as vertebrate prey or forage vegetation, exist for rice fields. Outside North America, Europe and Japan, little is known about abundance and importance of any avian food in rice fields. Currently, flooding rice fields after harvest is the best known management practice to attract and benefit birds. Studies from North America indicate specific agricultural practices (e.g. burning stubble) may increase use and improve access to food resources. Evaluating and implementing management practices that are ecologically sustainable, increase food for birds and are agronomically beneficial should be global priorities to integrate rice production and avian conservation. Finally, land area devoted to rice agriculture appears to be stable in the USA, declining in China, and largely unquantified in many regions. Monitoring trends in riceland area may provide information to guide avian conservation planning in rice-agriculture ecosystems.

  4. Moving Field Guides

    Science.gov (United States)

    Cassie Meador; Mark Twery; Meagan. Leatherbury

    2011-01-01

    The Moving Field Guides (MFG) project is a creative take on site interpretation. Moving Field Guides provide an example of how scientific and artistic endeavors work in parallel. Both begin with keen observations that produce information that must be analyzed, understood, and interpreted. That interpretation then needs to be communicated to others to complete the...

  5. 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...

  6. 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

  7. Avian Respiratory Coinfection and Impact on Avian Influenza Pathogenicity in Domestic Poultry: Field and Experimental Findings.

    Science.gov (United States)

    Samy, Ahmed; Naguib, Mahmoud M

    2018-02-24

    The avian respiratory system hosts a wide range of commensal and potential pathogenic bacteria and/or viruses that interact with each other. Such interactions could be either synergistic or antagonistic, which subsequently determines the severity of the disease complex. The intensive rearing methods of poultry are responsible for the marked increase in avian respiratory diseases worldwide. The interaction between avian influenza with other pathogens can guarantee the continuous existence of other avian pathogens, which represents a global concern. A better understanding of the impact of the interaction between avian influenza virus and other avian respiratory pathogens provides a better insight into the respiratory disease complex in poultry and can lead to improved intervention strategies aimed at controlling virus spread.

  8. Field avian metapneumovirus evolution avoiding vaccine induced immunity.

    Science.gov (United States)

    Catelli, Elena; Lupini, Caterina; Cecchinato, Mattia; Ricchizzi, Enrico; Brown, Paul; Naylor, Clive J

    2010-01-22

    Live avian metapneumovirus (AMPV) vaccines have largely brought turkey rhinotracheitis (TRT) under control in Europe but unexplained outbreaks still occur. Italian AMPV longitudinal farm studies showed that subtype B AMPVs were frequently detected in turkeys some considerable period after subtype B vaccination. Sequencing showed these to be unrelated to the previously applied vaccine. Sequencing of the entire genome of a typical later isolate showed numerous SH and G protein gene differences when compared to both a 1987 Italian field isolate and the vaccine in common use. Experimental challenge of vaccinated birds with recent virus showed that protection was inferior to that seen after challenge with the earlier 1987 isolate. Field virus had changed in key antigenic regions allowing replication and leading to disease in well vaccinated birds.

  9. Tripolar electric field Structure in guide field magnetic reconnection

    OpenAIRE

    S. Fu; S. Huang; M. Zhou; B. Ni; X. Deng

    2018-01-01

    It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection). In this paper, we performed 2.5-D electromagnetic full particle simulation to study the electric field structures in magnetic reconnection under different initial guide fields (Bg). Once the amplit...

  10. 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.

  11. Tripolar electric field Structure in guide field magnetic reconnection

    Science.gov (United States)

    Fu, Song; Huang, Shiyong; Zhou, Meng; Ni, Binbin; Deng, Xiaohua

    2018-03-01

    It has been shown that the guide field substantially modifies the structure of the reconnection layer. For instance, the Hall magnetic and electric fields are distorted in guide field reconnection compared to reconnection without guide fields (i.e., anti-parallel reconnection). In this paper, we performed 2.5-D electromagnetic full particle simulation to study the electric field structures in magnetic reconnection under different initial guide fields (Bg). Once the amplitude of a guide field exceeds 0.3 times the asymptotic magnetic field B0, the traditional bipolar Hall electric field is clearly replaced by a tripolar electric field, which consists of a newly emerged electric field and the bipolar Hall electric field. The newly emerged electric field is a convective electric field about one ion inertial length away from the neutral sheet. It arises from the disappearance of the Hall electric field due to the substantial modification of the magnetic field and electric current by the imposed guide field. The peak magnitude of this new electric field increases linearly with the increment of guide field strength. Possible applications of these results to space observations are also discussed.

  12. 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.

  13. Periodic updating of avian influenza vaccines is necessary to maintain effectiveness in the field

    Science.gov (United States)

    The impact of avian influenza on poultry production is undeniable. Field outbreaks of H5N1 HPAI have occurred in vaccinated flocks from both failure of the vaccines (i.e. vaccine efficacy) and failure in administration or immune response of the target species (i.e. vaccination effectiveness). Antige...

  14. Time to Spread Your Wings: A Review of the Avian Ancient DNA Field

    Directory of Open Access Journals (Sweden)

    Alicia Grealy

    2017-07-01

    Full Text Available Ancient DNA (aDNA has the ability to inform the evolutionary history of both extant and extinct taxa; however, the use of aDNA in the study of avian evolution is lacking in comparison to other vertebrates, despite birds being one of the most species-rich vertebrate classes. Here, we review the field of “avian ancient DNA” by summarising the past three decades of literature on this topic. Most studies over this time have used avian aDNA to reconstruct phylogenetic relationships and clarify taxonomy based on the sequencing of a few mitochondrial loci, but recent studies are moving toward using a comparative genomics approach to address developmental and functional questions. Applying aDNA analysis with more practical outcomes in mind (such as managing conservation is another increasingly popular trend among studies that utilise avian aDNA, but the majority of these have yet to influence management policy. We find that while there have been advances in extracting aDNA from a variety of avian substrates including eggshell, feathers, and coprolites, there is a bias in the temporal focus; the majority of the ca. 150 studies reviewed here obtained aDNA from late Holocene (100–1000 yBP material, with few studies investigating Pleistocene-aged material. In addition, we identify and discuss several other issues within the field that require future attention. With more than one quarter of Holocene bird extinctions occurring in the last several hundred years, it is more important than ever to understand the mechanisms driving the evolution and extinction of bird species through the use of aDNA.

  15. Night sky a falcon field guide

    CERN Document Server

    Nigro, Nicholas

    2012-01-01

    Night Sky: A Falcon Field Guide covers both summer and winter constellations, planets, and stars found in the northern hemisphere. Conveniently sized to fit in a pocket and featuring detailed photographs, this informative guide makes it easy to identify objects in the night sky even from one's own backyard. From information on optimal weather conditions, preferred viewing locations, and how to use key tools of the trade, this handbook will help you adeptly navigate to and fro the vast and dynamic nighttime skies, and you'll fast recognize that the night sky's the limit.

  16. 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

  17. 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 (<22%). With a few exceptions, identification accuracy did not differ significantly among image formats. In Cameroon, users identifying sterile Cola species achieved 46-56% accuracy across formats; identification was most accurate with living plant 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

  18. Modeling approaches in avian conservation and the role of field biologists

    Science.gov (United States)

    Beissinger, Steven R.; Walters, J.R.; Catanzaro, D.G.; Smith, Kimberly G.; Dunning, J.B.; Haig, Susan M.; Noon, Barry; Stith, Bradley M.

    2006-01-01

    This review grew out of our realization that models play an increasingly important role in conservation but are rarely used in the research of most avian biologists. Modelers are creating models that are more complex and mechanistic and that can incorporate more of the knowledge acquired by field biologists. Such models require field biologists to provide more specific information, larger sample sizes, and sometimes new kinds of data, such as habitat-specific demography and dispersal information. Field biologists need to support model development by testing key model assumptions and validating models. The best conservation decisions will occur where cooperative interaction enables field biologists, modelers, statisticians, and managers to contribute effectively. We begin by discussing the general form of ecological models—heuristic or mechanistic, "scientific" or statistical—and then highlight the structure, strengths, weaknesses, and applications of six types of models commonly used in avian conservation: (1) deterministic single-population matrix models, (2) stochastic population viability analysis (PVA) models for single populations, (3) metapopulation models, (4) spatially explicit models, (5) genetic models, and (6) species distribution models. We end by considering their unique attributes, determining whether the assumptions that underlie the structure are valid, and testing the ability of the model to predict the future correctly.

  19. 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

  20. A guide to safe field operations

    Science.gov (United States)

    Yobbi, D.K.; Yorke, T.H.; Mycyk, R.T.

    1996-01-01

    Most functions of the U.S. Geological Survey (USGS), Water Resources Division (WRD) require employees to participate in numerous field activities ranging from routine meetings with cooperators, other federal and public officials, and private citizens to potentially hazardous assignments, such as making flood measurements and scuba diving to service underwater instruments. It is paramount that each employee be aware of safety procedures and operational policies of the WRD to ensure that (1) their activities avoid or minimize personal injury to the employee, coworkers, or anyone in the vicinity of the field activity, and (2) their conduct does not infringe on the personal or property rights of any individual or organization. The purpose of the guide is to familiarize employees with the operational and safety procedures expected to be followed by each employee as a representative of the WRD. It is also intended as a training tool for all new employees and a document to be reviewed by each employee before undertaking a field assignment. It includes general procedures that are standard and applicable to all field operations, such as communication, vehicle operation, and adequate preparation for anticipated weather conditions. It also includes a discussion of specific procedures and safety considerations for most of the routine field assignments undertaken by hydrologists and hydrologic technicians of the WRD. The guide is not intended to be a technical handbook outlining step-by-step procedures for performing specific tasks or a comprehensive discussion of every possible activity that may be undertaken by a USGS employee. Employees are referred to the Techniques for Water-Resources Investigations (TWRI) series for specific technical procedures and to the U.S. Geological Survey Safety and Environmental Health Handbook 445-1-H (USGS, August 1989), USGS Occupational Hazards and Safety Procedures Handbook 445-2-H (December 1993), the WRD notebook on Safety Policy and

  1. Avian Biotechnology.

    Science.gov (United States)

    Nakamura, Yoshiaki

    2017-01-01

    Primordial germ cells (PGCs) generate new individuals through differentiation, maturation and fertilization. This means that the manipulation of PGCs is directly linked to the manipulation of individuals, making PGCs attractive target cells in the animal biotechnology field. A unique biological property of avian PGCs is that they circulate temporarily in the vasculature during early development, and this allows us to access and manipulate avian germ lines. Following the development of a technique for transplantation, PGCs have become central to avian biotechnology, in contrast to the use of embryo manipulation and subsequent transfer to foster mothers, as in mammalian biotechnology. Today, avian PGC transplantation combined with recent advanced manipulation techniques, including cell purification, cryopreservation, depletion, and long-term culture in vitro, have enabled the establishment of genetically modified poultry lines and ex-situ conservation of poultry genetic resources. This chapter introduces the principles, history, and procedures of producing avian germline chimeras by transplantation of PGCs, and the current status of avian germline modification as well as germplasm cryopreservation. Other fundamental avian reproductive technologies are described, including artificial insemination and embryo culture, and perspectives of industrial applications in agriculture and pharmacy are considered, including poultry productivity improvement, egg modification, disease resistance impairment and poultry gene "pharming" as well as gene banking.

  2. 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

  3. Interplanetary Magnetic Field Guiding Relativistic Particles

    Science.gov (United States)

    Masson, S.; Demoulin, P.; Dasso, S.; Klein, K. L.

    2011-01-01

    The origin and the propagation of relativistic solar particles (0.5 to few Ge V) in the interplanetary medium remains a debated topic. These relativistic particles, detected at the Earth by neutron monitors have been previously accelerated close to the Sun and are guided by the interplanetary magnetic field (IMF) lines, connecting the acceleration site and the Earth. Usually, the nominal Parker spiral is considered for ensuring the magnetic connection to the Earth. However, in most GLEs the IMF is highly disturbed, and the active regions associated to the GLEs are not always located close to the solar footprint of the nominal Parker spiral. A possible explanation is that relativistic particles are propagating in transient magnetic structures, such as Interplanetary Coronal Mass Ejections (ICMEs). In order to check this interpretation, we studied in detail the interplanetary medium where the particles propagate for 10 GLEs of the last solar cycle. Using the magnetic field and the plasma parameter measurements (ACE/MAG and ACE/SWEPAM), we found widely different IMF configurations. In an independent approach we develop and apply an improved method of the velocity dispersion analysis to energetic protons measured by SoHO/ERNE. We determined the effective path length and the solar release time of protons from these data and also combined them with the neutron monitor data. We found that in most of the GLEs, protons propagate in transient magnetic structures. Moreover, the comparison between the interplanetary magnetic structure and the interplanetary length suggest that the timing of particle arrival at Earth is dominantly determined by the type of IMF in which high energetic particles are propagating. Finally we find that these energetic protons are not significantly scattered during their transport to Earth.

  4. [A case of human highly pathogenic avian influenza in Shenzhen, China: application of field epidemiological study].

    Science.gov (United States)

    Zhang, Shun-Xiang; Cheng, Jin-Quan; Ma, Han-Wu; He, Jian-Fan; Cheng, Xiao-Wen; Jiang, Li-Juan; Mou, Jin; Wu, Chun-Li; Lv, Xing; Zhang, Shao-Hua; Zhang, Ya-De; Wu, Yong-Sheng; Wang, Xin

    2008-03-01

    Based on analyzing the characteristics of a case with human avian influenza and the effects of field epidemiological study. An emergency-response-system was started up to follow the probable human Highly Pathogenic Avian Influenza case initially detected by the "Undefined Pneumonia Surveillance System of Shenzhen". Public health professionals administered several epidemiologic investigations and giving all the contacts of the patient with a 7-day-long medical observation for temporally related influenza-like illness. Reverse transcriptase-polymerase chain reaction (RT-PCR) with primers for H5 and N1 was applied to test respiratory tract samples and/or throat swabs of the patient and all his contacts specific for the hemagglutinin gene of influenza A H5N1. Activities and strategies such as media response,notification in the public, communications with multiple related sectors, social participation and information exchange with Hong Kong were involved in field control and management. The patient was a male, 31 years old,with an occupation as a truck driver in a factory,and had been residing in Shenzhen for 7 years. Started with an influenza-like syndrome, the patient received treatment on the 4th day of the onset, from a clinic and on the 6th day from a regular hospital. On the 8th day of the disease course, he was confirmed by Shenzhen Center for Disease Control and Prevention as human avian flu case and was then transferred to Intensive Care Unit (ICU). On the 83rd day of commence, the patients was healed and released from the hospital. The patient had no significant exposure to sick poultry or poultry that died from the illness before the onset of the disease. The patient and five family members lived together, but no family member was affected and no contact showed positive results for H5N1. A small food market with live poultry, which was under formal supervision and before illness the patient once visited, located near his apartment. Totally, 35 swabs from live

  5. 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.

  6. Molecular Characterization and Cluster Analysis of Field Isolates of Avian Infectious Laryngotracheitis Virus from Argentina

    Directory of Open Access Journals (Sweden)

    María I. Craig

    2017-12-01

    Full Text Available Avian infectious laryngotracheitis (ILT is a worldwide infectious disease that causes important economic losses in the poultry industry. Although it is known that ILT virus (ILTV is present in Argentina, there is no information about the circulating strains. With the aim to characterize them, seven different genomic regions (thymidine kinase, glycoproteins D, G, B, C, and J, and infected cell polypeptide 4 were partially sequenced and compared between field samples. The gJ sequence resulted to be the most informative segment, it allowed the differentiation among field sample strains, and also, between wild and vaccine viruses. Specific changes in selected nucleotidic positions led to the definition of five distinct haplotypes. Tests for detection of clustering were run to test the null hypothesis that ILTV haplotypes were randomly distributed in time in Argentina and in space in the most densely populated poultry region of this country, Entre Rios. From this study, it was possible to identify a 46 km radius cluster in which higher proportions of haplotypes 4 and 5 were observed, next to a provincial route in Entre Rios and a significant decline of haplotype 5 between 2009 and 2011. Results here provide an update on the molecular epidemiology of ILT in Argentina, including data on specific genome segments that may be used for rapid characterization of the virus in the field. Ultimately, results will contribute to the surveillance of ILT in the country.

  7. Interaction between laser-produced plasma and guiding magnetic field

    International Nuclear Information System (INIS)

    Hasegawa, Jun; Takahashi, Kazumasa; Ikeda, Shunsuke; Nakajima, Mitsuo; Horioka, Kazuhiko

    2013-01-01

    Transportation properties of laser-produced plasma through a guiding magnetic field were examined. A drifting dense plasma produced by a KrF laser was injected into an axisymmetric magnetic field induced by permanent ring magnets. The plasma ion flux in the guiding magnetic field was measured by a Faraday cup at various distances from the laser target. Numerical analyses based on a collective focusing model were performed to simulate plasma particle trajectories and then compared with the experimental results. (author)

  8. Influence of a guide field on collisionless driven reconnection

    International Nuclear Information System (INIS)

    Horiuchi, Ritoku; Usami, Shunsuke; Ohtani, Hiroaki

    2014-01-01

    The influence of a guide field on collisionless driven reconnection is investigated by means of two-dimensional electromagnetic particle simulation in an open system. In a quasi-steady state when reconnection electric field evolves fully, a current layer evolves locally in a narrow kinetic region and its scale decreases in proportion to an electron meandering scale as the guide field is intensified. Here, the meandering scale stands for an average spatial scale of nongyrotropic motions in the vicinity of the reconnection point. Force terms associated with off-diagonal components of electron and ion pressure tensors, which are originating from nongyrotropic motions of charged particles, becomes dominant at the reconnection point and sustain the reconnection electric field even when the guide field is strong. It is also found that thermalization of both ions and electrons is suppressed by the guide field. For the weak guide field, an electron nonthermal component is significantly created through a fast outburst from the kinetic region, while for the strong guide field, an ion nonthermal component is generated through the acceleration by an in-plane electric field near the magnetic separatrix. (author)

  9. Healthy Water Healthy People Field Monitoring Guide

    Science.gov (United States)

    Project WET Foundation, 2003

    2003-01-01

    This 100-page manual serves as a technical reference for the "Healthy Water, Healthy People Water Quality Educators Guide" and the "Healthy Water Healthy People Testing Kits". Yielding in-depth information about ten water quality parameters, it answers questions about water quality testing using technical overviews, data interpretation guidelines,…

  10. 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…

  11. 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 ...

  12. Field guide to terahertz sources, detectors, and optics

    CERN Document Server

    O'Sullivan, Créidhe

    2012-01-01

    This SPIE Field Guide provides readers with a concise description of the quasi-optical techniques used to design THz systems, as well as the basic principles of operation of the most common THz components in use today.

  13. 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

  14. 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.

  15. Field guide to forest plants of northern Idaho

    Science.gov (United States)

    Patricia A. Patterson; Kenneth E. Neiman; Jonalea K. Tonn

    1985-01-01

    This field guide -- designed for use by people with minimal botanical training -- is an identification aid for nearly 200 plant species having ecological indicator value in northern Idaho forest habitat types. It contains line drawings, simplified taxonomic descriptions , characteristics tables, conspectuses, and keys. It emphasizes characteristics useful for field...

  16. 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...

  17. 76 FR 66032 - Availability of an Environmental Assessment for Field Testing Avian Influenza-Marek's Disease...

    Science.gov (United States)

    2011-10-25

    ... Avian Influenza-Marek's Disease Vaccine, H5 Subtype, Serotype 3, Live Marek's Disease Vector AGENCY...-Marek's Disease Vaccine, H5 Subtype, Serotype 3, Live Marek's Disease Vector. The environmental... notice unless new substantial issues bearing on the effects of this action are brought to our attention...

  18. Avian influenza vaccine development: Application technology platforms, field use and predictors of protection

    Science.gov (United States)

    Vaccines against avian influenza (AI) began over 100 years ago as experimentally produced products, but commercial application did not occur until: 1) a reliable method was developed to grow and titer the virus (i.e. embryonating chicken eggs), 2) an efficient and predictable method was developed to...

  19. 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. © 2015 The Society for Vector Ecology.

  20. 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

  1. A field guide to geophysics in archaeology

    CERN Document Server

    Oswin, John

    2009-01-01

    Geophysics operations in archaeology have become well known through exposure on television. However, the technique is presented as the action of specialists and something of a mystery, where people walk about with strange contraptions, and results appear from a computer. This is not the case, however. Some scientific knowledge is needed in order to understand how the machines work and what they detect but otherwise it is only necessary to know how to handle the instruments, how to survey a field and how to interpret the computer results. This book provides all the relevant information. It explains geophysics operations in archaeology, describes the science that gives the soil properties to measure and the means by which the instruments make their measurements. Dr John Oswin is in charge of the geophysics operation of the Bath and Camerton Archaeological Society and his work has recently been the subject of a television programme. He has taught many students how to use geophysical equipment.

  2. Effects of the reconnection electric field on crescent electron distribution functions in asymmetric guide field reconnection

    Science.gov (United States)

    Bessho, N.; Chen, L. J.; Hesse, M.; Wang, S.

    2017-12-01

    In asymmetric reconnection with a guide field in the Earth's magnetopause, electron motion in the electron diffusion region (EDR) is largely affected by the guide field, the Hall electric field, and the reconnection electric field. The electron motion in the EDR is neither simple gyration around the guide field nor simple meandering motion across the current sheet. The combined meandering motion and gyration has essential effects on particle acceleration by the in-plane Hall electric field (existing only in the magnetospheric side) and the out-of-plane reconnection electric field. We analyze electron motion and crescent-shaped electron distribution functions in the EDR in asymmetric guide field reconnection, and perform 2-D particle-in-cell (PIC) simulations to elucidate the effect of reconnection electric field on electron distribution functions. Recently, we have analytically expressed the acceleration effect due to the reconnection electric field on electron crescent distribution functions in asymmetric reconnection without a guide field (Bessho et al., Phys. Plasmas, 24, 072903, 2017). We extend the theory to asymmetric guide field reconnection, and predict the crescent bulge in distribution functions. Assuming 1D approximation of field variations in the EDR, we derive the time period of oscillatory electron motion (meandering + gyration) in the EDR. The time period is expressed as a hybrid of the meandering period and the gyro period. Due to the guide field, electrons not only oscillate along crescent-shaped trajectories in the velocity plane perpendicular to the antiparallel magnetic fields, but also move along parabolic trajectories in the velocity plane coplanar with magnetic field. The trajectory in the velocity space gradually shifts to the acceleration direction by the reconnection electric field as multiple bounces continue. Due to the guide field, electron distributions for meandering particles are bounded by two paraboloids (or hyperboloids) in the

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

    International Nuclear Information System (INIS)

    Last, G.V.; Liikala, T.L.

    1987-12-01

    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

  4. Field guide for Ontario Hydro shipments involving radioactive material

    International Nuclear Information System (INIS)

    Howe, W.

    1987-09-01

    This field guide consists of two parts. Part I deals with the packages used by Ontario Hydro for shipment of its radioactive materials. Highly radioactive material must be transported in rugged containers which will survive a severe transportation accident. These containers are known at Type B Packages. Each container used by Ontario Hydro for shipments of highly radioactive material has been allotted a single page in this field guide with specific information for quick reference. Each package identification card includes a description of the package and contents and the required safety marking. Photographs of both the container and the vehicle as well as a cross-sectional diagram will assist Ontario Hydro personnel as well as emergency response personnel in quick identification of containers and contents. Containers used for transportation of material will low levels of radioactivity are also briefly discussed. These containers could fail in the event of an accident but the radioactivity is limited to low levels. Part I of this field guide also summarizes general emergency response instructions which are applicable to any transportation accident involving a package with radioactive material. Part II of this field guide provides information about the requirements which must be met by Ontario Hydro prior to any shipment of radioactive material in Ontario

  5. Book Review Field Guide to the Birds of Macaronesia: Azores ...

    African Journals Online (AJOL)

    Book Review Field Guide to the Birds of Macaronesia: Azores, Madeira, Canary Islands, Cape Verde By Eduardo Garcia-del-Rey (2011). Ricardo Jorge Lopes. Abstract. Lynx Edicions, Montseny, 8, E-08193 Bellaterra, Barcelona, Spain 342 pages, including 150 colour plates and >230 detailed distribution maps, hardcover

  6. 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.

  7. 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.

  8. Automated particulate sampler field test model operations guide

    Energy Technology Data Exchange (ETDEWEB)

    Bowyer, S.M.; Miley, H.S.

    1996-10-01

    The Automated Particulate Sampler Field Test Model Operations Guide is a collection of documents which provides a complete picture of the Automated Particulate Sampler (APS) and the Field Test in which it was evaluated. The Pacific Northwest National Laboratory (PNNL) Automated Particulate Sampler was developed for the purpose of radionuclide particulate monitoring for use under the Comprehensive Test Ban Treaty (CTBT). Its design was directed by anticipated requirements of small size, low power consumption, low noise level, fully automatic operation, and most predominantly the sensitivity requirements of the Conference on Disarmament Working Paper 224 (CDWP224). This guide is intended to serve as both a reference document for the APS and to provide detailed instructions on how to operate the sampler. This document provides a complete description of the APS Field Test Model and all the activity related to its evaluation and progression.

  9. Electromagnetic dissipation during asymmetric reconnection with a moderate guide field

    Science.gov (United States)

    Genestreti, Kevin; Burch, James; Cassak, Paul; Torbert, Roy; Phan, Tai; Ergun, Robert; Giles, Barbara; Russell, Chris; Wang, Shan; Akhavan-Tafti, Mojtaba; Varsani, Ali

    2017-04-01

    We calculate the work done on the plasma by the electromagnetic (EM) field, ⃗Jṡ⃗E', and analyze the related electron currents and electric fields, focusing on a single asymmetric guide field electron diffusion region (EDR) event observed by MMS on 8 December 2015. For this event, each of the four MMS spacecraft observed dissipation of EM energy at the in-plane magnetic null point, though large-scale generation/dissipation was observed inconsistently on the magnetospheric side of the boundary. The current at the null was carried by a beam-like population of magnetosheath electrons traveling anti-parallel to the guide field, whereas the current on the Earthward side of the boundary was carried by crescent-shaped electron distributions. We also analyze the terms in Ohm's law, finding a large residual electric field throughout the EDR, inertial and pressure divergence fields at the null, and pressure divergence fields at the magnetosphere-side EDR. Our analysis of the terms in Ohm's law suggests that the EDR had significant three-dimensional structure.

  10. Three dimensional density cavities in guide field collisionless magnetic reconnection

    Science.gov (United States)

    Markidis, S.; Lapenta, G.; Divin, A.; Goldman, M.; Newman, D.; Andersson, L.

    2012-03-01

    Particle-in-cell simulations of collisionless magnetic reconnection with a guide field reveal for the first time the three dimensional features of the low density regions along the magnetic reconnection separatrices, the so-called cavities. It is found that structures with further lower density develop within the cavities. Because their appearance is similar to the rib shape, these formations are here called low density ribs. Their location remains approximately fixed in time and their density progressively decreases, as electron currents along the cavities evacuate them. They develop along the magnetic field lines and are supported by a strong perpendicular electric field that oscillates in space. In addition, bipolar parallel electric field structures form as isolated spheres between the cavities and the outflow plasma, along the direction of the low density ribs and of magnetic field lines.

  11. Feasibility of MRI guided proton therapy: magnetic field dose effects

    International Nuclear Information System (INIS)

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

    2008-01-01

    Many methods exist to improve treatment outcome in radiotherapy. Two of these are image-guided radiotherapy (IGRT) and proton therapy. IGRT aims at a more precise delivery of the radiation, while proton therapy is able to achieve more conformal dose distributions. In order to maximally exploit the sharp dose gradients from proton therapy it has to be combined with soft-tissue based IGRT. MRI-guided photon therapy (currently under development) offers unequalled soft-tissue contrast and real-time image guidance. A hybrid MRI proton therapy system would combine these advantages with the advantageous dose steering capacity of proton therapy. This paper addresses a first technical feasibility issue of this concept, namely the impact of a 0.5 T magnetic field on the dose distribution from a 90 MeV proton beam. In contrast to photon therapy, for MR-guided proton therapy the impact of the magnetic field on the dose distribution is very small. At tissue-air interfaces no effect of the magnetic field on the dose distribution can be detected. This is due to the low-energy of the secondary electrons released by the heavy protons.

  12. Endogenous electric fields as guiding cue for cell migration.

    Science.gov (United States)

    Funk, Richard H W

    2015-01-01

    This review covers two topics: (1) "membrane potential of low magnitude and related electric fields (bioelectricity)" and (2) "cell migration under the guiding cue of electric fields (EF)."Membrane potentials for this "bioelectricity" arise from the segregation of charges by special molecular machines (pumps, transporters, ion channels) situated within the plasma membrane of each cell type (including eukaryotic non-neural animal cells). The arising patterns of ion gradients direct many cell- and molecular biological processes such as embryogenesis, wound healing, regeneration. Furthermore, EF are important as guiding cues for cell migration and are often overriding chemical or topographic cues. In osteoblasts, for instance, the directional information of EF is captured by charged transporters on the cell membrane and transferred into signaling mechanisms that modulate the cytoskeleton and motor proteins. This results in a persistent directional migration along an EF guiding cue. As an outlook, we discuss questions concerning the fluctuation of EF and the frequencies and mapping of the "electric" interior of the cell. Another exciting topic for further research is the modeling of field concepts for such distant, non-chemical cellular interactions.

  13. A Field Guide to Constructivism in the College Science Classroom: Four Essential Criteria and a Guide to Their Usage

    Science.gov (United States)

    Hartle, R. Todd; Baviskar, Sandhya; Smith, Rosemary

    2012-01-01

    This field guide provides four essential criteria for constructivism as well as a guide for using these criteria to identify and assess the level of constructivism being used in an educational experience. The criteria include: 1) prior knowledge, 2) cognitive dissonance, 3) application with feedback, and 4) metacognition. This guide provides…

  14. Avian anemia's

    Directory of Open Access Journals (Sweden)

    Raukar Jelena

    2005-01-01

    Full Text Available This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematological parameters for every single avian species.

  15. 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

  16. First Report of Avian Metapneumovirus Subtype B Field Strain in a Romanian Broiler Flock During an Outbreak of Respiratory Disease.

    Science.gov (United States)

    Franzo, Giovanni; Tucciarone, Claudia Maria; Enache, Mirel; Bejan, Violeta; Ramon, Gema; Koutoulis, Konstantinos C; Cecchinato, Mattia

    2017-06-01

    Avian metapneumovirus (aMPV) represents one of the most prevalent diseases of turkey, especially in combination with other pathogens, and its frequency is also increasing among chickens. Despite this evidence, epidemiologic data are poor and scattered, severely preventing control of the disease even in highly developed areas such as Europe. In the present study, the detection and characterization of an aMPV subtype B strain circulating in a vaccinated but symptomatic Romanian broiler flock is reported for the first time. The phylogenetic analysis based on the partial G gene sequence demonstrates the close relationship of the Romanian virus with a group of recently emerged Italian field strains for which vaccine-induced protection was experimentally proven to be partial. These preliminary results allow us to hypothesize the spreading of vaccine-escaping aMPV subtype B strains through Europe and, consequently, dictate the carrying out of a more systematic survey to confirm this theory and enforce adequate countermeasures.

  17. Efficient Injection of Electron Beams into Magnetic Guide Fields

    International Nuclear Information System (INIS)

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

    1999-01-01

    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

  18. Practical guide to organic field effect transistor circuit design

    CERN Document Server

    Sou, Antony

    2016-01-01

    The field of organic electronics spans a very wide range of disciplines from physics and chemistry to hardware and software engineering. This makes the field of organic circuit design a daunting prospect full of intimidating complexities, yet to be exploited to its true potential. Small focussed research groups also find it difficult to move beyond their usual boundaries and create systems-on-foil that are comparable with the established silicon world.This book has been written to address these issues, intended for two main audiences; firstly, physics or materials researchers who have thus far designed circuits using only basic drawing software; and secondly, experienced silicon CMOS VLSI design engineers who are already knowledgeable in the design of full custom transistor level circuits but are not familiar with organic devices or thin film transistor (TFT) devices.In guiding the reader through the disparate and broad subject matters, a concise text has been written covering the physics and chemistry of the...

  19. Teach Like a Champion Field Guide: A Practical Resource to Make the 49 Techniques Your Own

    Science.gov (United States)

    Lemov, Doug

    2012-01-01

    In his acclaimed book "Teach Like a Champion", Doug Lemov shared 49 essential techniques used by excellent teachers. In his companion Field Guide, he further explores those techniques in a practical guide. With the "Teach Like a Champion Field Guide", teachers will have an indispensable resource that complements their classroom application of…

  20. Avian anemia's

    OpenAIRE

    Raukar Jelena

    2005-01-01

    This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematologica...

  1. Cone-guided fast ignition with no imposed magnetic fields

    Directory of Open Access Journals (Sweden)

    Strozzi D.

    2013-11-01

    Full Text Available Simulations are presented of ignition-scale fast ignition targets with the integrated Zuma-Hydra PIC-hydrodynamic capability. We consider a spherical DT fuel assembly with a carbon cone, and an artificially-collimated fast electron source. We study the role of E and B fields and the fast electron energy spectrum. For mono-energetic 1.5 MeV fast electrons, without E and B fields, ignition can be achieved with fast electron energy Efig = 30kJ. This is 3.5× the minimal deposited ignition energy of 8.7 kJ for our fuel density of 450 g/cm3. Including E and B fields with the resistive Ohm's law E = ηJb gives Efig = 20kJ, while using the full Ohm's law gives Efig > 40 kJ. This is due to magnetic self-guiding in the former case, and ∇n ×∇T magnetic fields in the latter. Using a realistic, quasi two-temperature energy spectrum derived from PIC laser-plasma simulations increases Efig to (102, 81, 162 kJ for (no E/B, E = ηJb, full Ohm's law. Such electrons are too energetic to stop in the optimal hot spot depth.

  2. Guides to . . . Histories of . . . Who Delineates the Field? On Reading ...

    African Journals Online (AJOL)

    The question in the title above is prompted by my being invited to review the recently published 251-page Columbia Guide to South African Literature in English since 1945 (2010), by Gareth Cornwell, Dirk Klopper and Craig MacKenzie. It is a guide that follows closely on another guide, the A–Z of. African Writers: A Guide to ...

  3. Turbulent transport in 2D collisionless guide field reconnection

    Science.gov (United States)

    Muñoz, P. A.; Büchner, J.; Kilian, P.

    2017-02-01

    Transport in hot and dilute, i.e., collisionless, astrophysical and space, plasmas is called "anomalous." This transport is due to the interaction between the particles and the self-generated turbulence by their collective interactions. The anomalous transport has very different and not well known properties compared to the transport due to binary collisions, dominant in colder and denser plasmas. 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. This configuration is typical for stellar coronae, and it is created in the laboratory for which a 2.5D geometry applies. In our analysis, in addition to the immediate vicinity of the X-line, we also include regions outside and near the separatrices. We analyze the anomalous transport properties by using 2.5D Particle-in-Cell 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 (due to a net momentum transfer from particles to waves) 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 streaming instabilities, is mainly electrostatic and "patchy" in space, and so is the associated anomalous transport. Parts of the energy exchange between turbulence and particles are reversible and quasi-periodic. The remaining irreversible anomalous resistivity can be parametrized by an effective collision rate ranging from the local ion-cyclotron to the lower-hybrid frequency. The contributions to the parallel and the perpendicular (to the magnetic

  4. Scales of guide field reconnection at the hydrogen mass ratio

    International Nuclear Information System (INIS)

    Lapenta, G.; Markidis, S.; Divin, A.; Goldman, M.; Newman, D.

    2010-01-01

    We analyze the signatures of component reconnection for a Harris current sheet with a guide field using the physical mass ratio of hydrogen. The study uses the fully kinetic particle in cell code IPIC3D to investigate the scaling with mass ratio of the following three main component reconnection features: electron density cavities along the separatrices, channels of fast electron flow within the cavities, and electron phase space holes due to the Buneman instability in the electron high speed channels. The width and strength of the electron holes and of the electron cavities are studied up the mass ratio proper of hydrogen, considering the effect of the simulation box size, and of the boundary conditions. The results compare favorably with the existing data from the Cluster and Themis missions and provide quantitative predictions for realistic conditions to be encountered by the planned magnetospheric multiscale mission.

  5. Neural field model of memory-guided search.

    Science.gov (United States)

    Kilpatrick, Zachary P; Poll, Daniel B

    2017-12-01

    Many organisms can remember locations they have previously visited during a search. Visual search experiments have shown exploration is guided away from these locations, reducing redundancies in the search path before finding a hidden target. We develop and analyze a two-layer neural field model that encodes positional information during a search task. A position-encoding layer sustains a bump attractor corresponding to the searching agent's current location, and search is modeled by velocity input that propagates the bump. A memory layer sustains persistent activity bounded by a wave front, whose edges expand in response to excitatory input from the position layer. Search can then be biased in response to remembered locations, influencing velocity inputs to the position layer. Asymptotic techniques are used to reduce the dynamics of our model to a low-dimensional system of equations that track the bump position and front boundary. Performance is compared for different target-finding tasks.

  6. Geologic field-trip guide to Long Valley Caldera, California

    Science.gov (United States)

    Hildreth, Wes; Fierstein, Judy

    2017-07-26

    This guide to the geology of Long Valley Caldera is presented in four parts: (1) An overview of the volcanic geology; (2) a chronological summary of the principal geologic events; (3) a road log with directions and descriptions for 38 field-trip stops; and (4) a summary of the geophysical unrest since 1978 and discussion of its causes. The sequence of stops is arranged as a four-day excursion for the quadrennial General Assembly of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI), centered in Portland, Oregon, in August 2017. Most stops, however, are written freestanding, with directions that allow each one to be visited independently, in any order selected.

  7. Neural field model of memory-guided search

    Science.gov (United States)

    Kilpatrick, Zachary P.; Poll, Daniel B.

    2017-12-01

    Many organisms can remember locations they have previously visited during a search. Visual search experiments have shown exploration is guided away from these locations, reducing redundancies in the search path before finding a hidden target. We develop and analyze a two-layer neural field model that encodes positional information during a search task. A position-encoding layer sustains a bump attractor corresponding to the searching agent's current location, and search is modeled by velocity input that propagates the bump. A memory layer sustains persistent activity bounded by a wave front, whose edges expand in response to excitatory input from the position layer. Search can then be biased in response to remembered locations, influencing velocity inputs to the position layer. Asymptotic techniques are used to reduce the dynamics of our model to a low-dimensional system of equations that track the bump position and front boundary. Performance is compared for different target-finding tasks.

  8. Scales of guide field reconnection at the hydrogen mass ratio

    Science.gov (United States)

    Lapenta, G.; Markidis, S.; Divin, A.; Goldman, M.; Newman, D.

    2010-08-01

    We analyze the signatures of component reconnection for a Harris current sheet with a guide field using the physical mass ratio of hydrogen. The study uses the fully kinetic particle in cell code IPIC3D to investigate the scaling with mass ratio of the following three main component reconnection features: electron density cavities along the separatrices, channels of fast electron flow within the cavities, and electron phase space holes due to the Buneman instability in the electron high speed channels. The width and strength of the electron holes and of the electron cavities are studied up the mass ratio proper of hydrogen, considering the effect of the simulation box size, and of the boundary conditions. The results compare favorably with the existing data from the Cluster and Themis missions and provide quantitative predictions for realistic conditions to be encountered by the planned magnetospheric multiscale mission.

  9. Avian Metapneumoviruses

    Science.gov (United States)

    Avian metapneumovirus (aMPV) is an economically important virus that is the primary causal agent of turkey rhinotracheitis (TRT), also known as avian rhinotracheitis (ART). The virus causes an acute highly contagious infection of the upper respiratory tract in turkeys and was first isolated from tur...

  10. Miller Creek Demonstration Forest ecology activities - a teachers supplement to the field guide

    Science.gov (United States)

    Bill Schustrom; Reed Kuennen; Raymond C. Shearer

    1998-01-01

    Miller Creek, on the Flathead National Forest in northwestern Montana, is a demonstration forest, showing up to 30 years of forest change. This teachers supplement to the educational field guide (Miller Creek Demonstration Forest - a forest born of fire: a field guide; Gen. Tech. Rep. RMRS-GTR-7, 1998) outlines eight field and classroom activities that teach students a...

  11. Longitudinal field studies of avian metapneumovirus and turkey hemorrhagic enteritis virus in turkeys suffering from colibacillosis associated mortality.

    Science.gov (United States)

    Giovanardi, Davide; Lupini, Caterina; Pesente, Patrizia; Rossi, Giulia; Ortali, Giovanni; Catelli, Elena

    2014-06-01

    The aim of this study was to evaluate if the exposure to Avian metapneumovirus (aMPV) and/or to Turkey hemorrhagic enteritis virus (THEV) was significant for the induction of episodes of colibacillosis in aMPV and THEV vaccinated turkeys. Colibacillosis-associated mortality was recorded and longitudinal virological studies performed in three consecutive turkey flocks reared in the same farm. aMPV and THEV diagnostic swabs and blood samples were made once a week up to 14 weeks of age. Swabs were processed by molecular techniques for viruses detection and antibody titres were evaluated. Field subtype B aMPVs were detected in all flocks at different ages of life always associated with respiratory signs and increase of colibacillosis-associated mortality. THEV has been consistently detected in all flocks since the 9th week of age. Vaccination with a single dose of the THEV commercial inactivated vaccine available in Italy seems does not protect the birds from the infection. Sequence comparison of the hexon protein of one of the THEV strains detected, and strains isolated worldwide, revealed high similarity between them. These results are consistent with the notion that the hexon protein, being the major antigenic component of the virus, is highly conserved between the strains. Results showed that field aMPV infection is directly correlated to colibacillosis-associated mortality. Less clear appears the role of THEV because the endemicity of aMPV makes difficult to evaluate its role in predisposing colibacillosis in absence of aMPV. It would be interesting to further investigate this issue through experimental trials in secure isolation conditions.

  12. 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

  13. Electron cyclotron maser instability (ECMI in strong magnetic guide field reconnection

    Directory of Open Access Journals (Sweden)

    R. A. Treumann

    2017-08-01

    Full Text Available The ECMI model of electromagnetic radiation from electron holes is shown to be applicable to spontaneous magnetic reconnection. We apply it to reconnection in strong current-aligned magnetic guide fields. Such guide fields participate only passively in reconnection, which occurs in the antiparallel components to both sides of the guide-field-aligned current sheets with current carried by kinetic Alfvén waves. Reconnection generates long (the order of hundreds of electron inertial scales electron exhaust regions at the reconnection site X point, which are extended perpendicular to the current and the guide fields. Exhausts contain a strongly density-depleted hot electron component and have properties similar to electron holes. Exhaust electron momentum space distributions are highly deformed, exhibiting steep gradients transverse to both the reconnecting and guide fields. Such properties suggest application of the ECMI mechanism with the fundamental ECMI X-mode emission beneath the nonrelativistic guide field cyclotron frequency in localized source regions. An outline of the mechanism and its prospects is given. Potential applications are the kilometric radiation (AKR in auroral physics, solar radio emissions during flares, planetary emissions and astrophysical scenarios (radiation from stars and compact objects involving the presence of strong magnetic fields and field-aligned currents. Drift of the exhausts along the guide field maps the local field and plasma properties. Escape of radiation from the exhaust and radiation source region still poses a problem. The mechanism can be studied in 2-D particle simulations of strong guide field reconnection which favours 2-D, mapping the deformation of the electron distribution perpendicular to the guide field, and using it in the numerical calculation of the ECMI growth rate. The mechanism suggests also that reconnection in general may become a source of the ECMI with or without guide fields. This is

  14. Electron cyclotron maser instability (ECMI) in strong magnetic guide field reconnection

    Science.gov (United States)

    Treumann, Rudolf A.; Baumjohann, Wolfgang

    2017-08-01

    The ECMI model of electromagnetic radiation from electron holes is shown to be applicable to spontaneous magnetic reconnection. We apply it to reconnection in strong current-aligned magnetic guide fields. Such guide fields participate only passively in reconnection, which occurs in the antiparallel components to both sides of the guide-field-aligned current sheets with current carried by kinetic Alfvén waves. Reconnection generates long (the order of hundreds of electron inertial scales) electron exhaust regions at the reconnection site X point, which are extended perpendicular to the current and the guide fields. Exhausts contain a strongly density-depleted hot electron component and have properties similar to electron holes. Exhaust electron momentum space distributions are highly deformed, exhibiting steep gradients transverse to both the reconnecting and guide fields. Such properties suggest application of the ECMI mechanism with the fundamental ECMI X-mode emission beneath the nonrelativistic guide field cyclotron frequency in localized source regions. An outline of the mechanism and its prospects is given. Potential applications are the kilometric radiation (AKR) in auroral physics, solar radio emissions during flares, planetary emissions and astrophysical scenarios (radiation from stars and compact objects) involving the presence of strong magnetic fields and field-aligned currents. Drift of the exhausts along the guide field maps the local field and plasma properties. Escape of radiation from the exhaust and radiation source region still poses a problem. The mechanism can be studied in 2-D particle simulations of strong guide field reconnection which favours 2-D, mapping the deformation of the electron distribution perpendicular to the guide field, and using it in the numerical calculation of the ECMI growth rate. The mechanism suggests also that reconnection in general may become a source of the ECMI with or without guide fields. This is of particular

  15. Avian influenza

    Science.gov (United States)

    ... develop flu-like symptoms within 10 days of handling infected birds or being in an area with ... your provider if you become sick after you return from your trip. Current information regarding avian flu ...

  16. Avian Flu

    International Nuclear Information System (INIS)

    Eckburg, Paul

    2006-01-01

    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.

  17. Book review: Peeters, H. 2007. Field guide to owls of California and the West

    Science.gov (United States)

    Eric D. Forsman

    2010-01-01

    Field Guide to Owls of California and the West. Written primarily for nonprofessionals,this little field guide is a treasure trove of published and unpublished information on the natural history and distribution of owls in the western United States. It covers just about everything you could want to know about owls, from why they take dust baths, to facultative...

  18. 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 ...

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

    International Nuclear Information System (INIS)

    Xia Xinren; Yin Chengyou

    2009-01-01

    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)

  20. Field effectiveness of highly pathogenic avian influenza H5N1 vaccination in commercial layers in Indonesia.

    Directory of Open Access Journals (Sweden)

    Simson Tarigan

    Full Text Available Although vaccination of poultry for control of highly pathogenic avian influenza virus (HPAIV H5N1 has been practiced during the last decade in several countries, its effectiveness under field conditions remains largely unquantified. Effective HPAI vaccination is however essential in preventing incursions, silent infections and generation of new H5N1 antigenic variants. The objective of this study was to asses the level and duration of vaccine induced immunity in commercial layers in Indonesia. Titres of H5N1 haemagglutination inhibition (HI antibodies were followed in individual birds from sixteen flocks, age 18-68 week old (wo. The study revealed that H5N1 vaccination had highly variable outcome, including vaccination failures, and was largely ineffective in providing long lasting protective immunity. Flocks were vaccinated with seven different vaccines, administer at various times that could be grouped into three regimes: In regime A, flocks (n = 8 were vaccinated two or three times before 19 wo; in regime B (n = 2, two times before and once after 19 wo; and in regime C (n = 6 three to four times before and two to three times after 19 wo. HI titres in regime C birds were significantly higher during the entire observation period in comparison to titres of regime A or B birds, which also differed significantly from each other. The HI titres of individual birds in each flock differed significantly from birds in other flocks, indicating that the effectiveness of field vaccination was highly variable and farm related. Protective HI titres of >4log2, were present in the majority of flocks at 18 wo, declined thereafter at variable rate and only two regime C flocks had protective HI titres at 68 wo. Laboratory challenge with HPAIV H5N1 of birds from regime A and C flocks confirmed that protective immunity differed significantly between flocks vaccinated by these two regimes. The study revealed that effectiveness of the currently applied H5N1

  1. Nonlinear instability of thin current sheets in antiparallel and guided magnetic fields

    Science.gov (United States)

    Silin, I.; Büchner, J.

    2003-09-01

    The influence of a current-aligned guide magnetic field on the nonlinear resonant instability of thin current sheets is investigated by means of three-dimensional Vlasov-code simulations. Similarly to the zero-guide field case, the pressure gradient excites lower-hybrid-drift (LHD) waves at the current sheet edges. However, since the LHD waves are excited perpendicular to the local magnetic field they propagate obliquely to the current direction. As a result, the number of resonant particles, i.e., the drift-resonance efficiency, decreases with increasing guide field strength. Hence, the driving of global current sheet kink/sausage instabilities becomes less efficient.

  2. Nonlinear instability of thin current sheets in antiparallel and guided magnetic fields

    International Nuclear Information System (INIS)

    Silin, I.; Buechner, J.

    2003-01-01

    The influence of a current-aligned guide magnetic field on the nonlinear resonant instability of thin current sheets is investigated by means of three-dimensional Vlasov-code simulations. Similarly to the zero-guide field case, the pressure gradient excites lower-hybrid-drift (LHD) waves at the current sheet edges. However, since the LHD waves are excited perpendicular to the local magnetic field they propagate obliquely to the current direction. As a result, the number of resonant particles, i.e., the drift-resonance efficiency, decreases with increasing guide field strength. Hence, the driving of global current sheet kink/sausage instabilities becomes less efficient

  3. Effects of a Guide Field on the Larmor Electric Field and Upstream Electron Temperature Anisotropy in Collisionless Asymmetric Magnetic Reconnection

    Energy Technology Data Exchange (ETDEWEB)

    Ek-In, Surapat; Ruffolo, David [Department of Physics, Faculty of Science, Mahidol University, Bangkok (Thailand); Malakit, Kittipat [Department of Physics, Faculty of Science and Techonology, Thammasat University, Pathum Thani (Thailand); Shay, Michael A. [Department of Physics and Astronomy, University of Delaware, Newark, DE (United States); Cassak, Paul A., E-mail: kmalakit@gmail.com [Department of Physics and Astronomy, West Virginia University, Morgantown, WV (United States)

    2017-08-20

    We perform the first study of the properties of the Larmor electric field (LEF) in collisionless asymmetric magnetic reconnection in the presence of an out-of-plane (guide) magnetic field for different sets of representative upstream parameters at Earth’s dayside magnetopause with an ion temperature greater than the electron temperature (the ion-to-electron temperature ratio fixed at 2) using two-dimensional particle-in-cell simulations. We show that the LEF does persist in the presence of a guide field. We study how the LEF thickness and strength change as a function of guide field and the magnetospheric temperature and reconnecting magnetic field strength. We find that the thickness of the LEF structure decreases, while its magnitude increases when a guide field is added to the reconnecting magnetic field. The added guide field makes the Larmor radius smaller, so the scaling with the magnetospheric ion Larmor radius is similar to that reported for the case without a guide field. Note, however, that the physics causing the LEF is not well understood, so future work in other parameter regimes is needed to fully predict the LEF for arbitrary conditions. We also find that a previously reported upstream electron temperature anisotropy arises in the vicinity of the LEF region both with and without a guide field. We argue that the generation of the anisotropy is linked to the existence of the LEF. The LEF can be used in combination with the electron temperature anisotropy as a signature to effectively identify dayside reconnection sites in observations.

  4. Avian influenza

    DEFF Research Database (Denmark)

    EFSA Panel on Animal Health and Welfare; More, Simon; Bicout, Dominique

    2017-01-01

    Previous introductions of highly pathogenic avian influenza virus (HPAIV) to the EU were most likely via migratory wild birds. A mathematical model has been developed which indicated that virus amplification and spread may take place when wild bird populations of sufficient size within EU become...... infected. Low pathogenic avian influenza virus (LPAIV) may reach similar maximum prevalence levels in wild bird populations to HPAIV but the risk of LPAIV infection of a poultry holding was estimated to be lower than that of HPAIV. Only few non-wild bird pathways were identified having a non...

  5. ON MULTIPLE RECONNECTION X-LINES AND TRIPOLAR PERTURBATIONS OF STRONG GUIDE MAGNETIC FIELDS

    International Nuclear Information System (INIS)

    Eriksson, S.; Gosling, J. T.; Lapenta, G.; Newman, D. L.; Goldman, M. V.; Phan, T. D.; Lavraud, B.; Khotyaintsev, Yu. V.; Carr, C. M.; Markidis, S.

    2015-01-01

    We report new multi-spacecraft Cluster observations of tripolar guide magnetic field perturbations at a solar wind reconnection exhaust in the presence of a guide field B M   which is almost four times as strong as the reversing field B L . The novel tripolar field consists of two narrow regions of depressed B M , with an observed 7%–14% ΔB M magnitude relative to the external field, which are found adjacent to a wide region of enhanced B M within the exhaust. A stronger reversing field is associated with each B M depression. A kinetic reconnection simulation for realistic solar wind conditions and the observed strong guide field reveals that tripolar magnetic fields preferentially form across current sheets in the presence of multiple X-lines as magnetic islands approach one another and merge into fewer and larger islands. The simulated ΔB M /ΔX N over the normal width ΔX N between a B M minimum and the edge of the external region agree with the normalized values observed by Cluster. We propose that a tripolar guide field perturbation may be used to identify candidate regions containing multiple X-lines and interacting magnetic islands at individual solar wind current sheets with a strong guide field

  6. Experimental verification of the role of electron pressure in fast magnetic reconnection with a guide field

    Science.gov (United States)

    Fox, W.

    2017-10-01

    Magnetic reconnection enables explosive conversion of magnetic field energy to plasma kinetic energy in space and laboratory plasmas. In many reconnecting plasmas in space, solar, and laboratory plasmas, reconnection proceeds in the presence of a finite guide field (GF) such that the magnetic field lines meet at an angle less than 180°, and in magnetic fusion devices the guide field can be the largest component of the field. We report detailed laboratory observations of the structure of reconnection current sheets in a two-fluid plasma regime with a guide magnetic field. We observe and quantitatively analyze the quadrupolar electron pressure variation in the ion-diffusion region, as originally predicted by extended magnetohydrodynamics simulations. The projection of the electron pressure gradient parallel to the magnetic field contributes significantly to balancing the parallel electric field, and the results demonstrate how parallel and perpendicular force balance are coupled in guide field reconnection and confirm basic theoretical models of the importance of electron pressure gradients for obtaining fast magnetic reconnection. I discuss connections to observations of reconnection with finite guide field by spacecraft missions, and implications for two-fluid reconnection in magnetic fusion devices.

  7. Suitability for field service in 4 breeds of guide dogs

    NARCIS (Netherlands)

    Ennik, E.; Liinamo, A.E.; Leighton, E.; Arendonk, van J.A.M.

    2006-01-01

    This study examines the relative importance of a longer than normal 4-month training period, or being ¿passed back¿ from the original training class to join a class in which dogs are at an earlier stage of their training, on the overall probability that a dog entering guide dog training will

  8. Interaction between Gaming and Multistage Guiding Strategies on Students' Field Trip Mobile Learning Performance and Motivation

    Science.gov (United States)

    Chen, Chih-Hung; Liu, Guan-Zhi; Hwang, Gwo-Jen

    2016-01-01

    In this study, an integrated gaming and multistage guiding approach was proposed for conducting in-field mobile learning activities. A mobile learning system was developed based on the proposed approach. To investigate the interaction between the gaming and guiding strategies on students' learning performance and motivation, a 2 × 2 experiment was…

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

    Directory of Open Access Journals (Sweden)

    R. D. Stevenson

    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.

  10. Book Review Helm Field Guides — Birds of Chile including the ...

    African Journals Online (AJOL)

    Book Review Helm Field Guides — Birds of Chile including the Antarctic Peninsula, the Falkland Islands and South Georgia by Albaro Jaramillo with illustrations by Peter Burke and David Beadle (2003)

  11. 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.

  12. Avian Influenza.

    Science.gov (United States)

    Zeitlin, Gary Adam; Maslow, Melanie Jane

    2005-05-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur.

  13. Avian cholera

    Science.gov (United States)

    Friend, Milton

    1999-01-01

    Avian cholera is a contagious disease resulting from infection by the bacterium Pasteurella multocida. Several subspecies of bacteria have been proposed for P. multocida, and at least 16 different P. multocida serotypes or characteristics of antigens in bacterial cells that differentiate bacterial variants from each other have been recognized. The serotypes are further differentiated by other methods, including DNA fingerprinting. These evaluations are useful for studying the ecology of avian cholera (Fig. 7.1), because different serotypes are generally found in poultry and free-ranging migratory birds. These evaluations also show that different P. multocida serotypes are found in wild birds in the eastern United States than those that are found in the birds in the rest of the Nation (Fig. 7.2).

  14. 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...

  15. Standard Guide for Conducting Corrosion Tests in Field Applications

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This guide covers procedures for conducting corrosion tests in plant equipment or systems under operating conditions to evaluate the corrosion resistance of engineering materials. It does not cover electrochemical methods for determining corrosion rates. 1.1.1 While intended primarily for immersion tests, general guidelines provided can be applicable for exposure of test specimens in plant atmospheres, provided that placement and orientation of the test specimens is non-restrictive to air circulation. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. See also 10.4.2.

  16. Tridimensional to bidimensional transition in magnetohydrodynamic turbulence with a guide field and kinetic helicity injection

    Science.gov (United States)

    Sujovolsky, N. E.; Mininni, P. D.

    2016-09-01

    We study the transition in dimensionality of a three-dimensional magnetohydrodynamic flow forced only mechanically when the strength of a magnetic guide 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 guide field is increased, the strength of the magnetic field fluctuations decreases as a power law of the guide field intensity. We show that for strong enough guide 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 be used to derive scaling laws for the velocity field.

  17. Ultra High Field MRI-Guided Deep Brain Stimulation.

    Science.gov (United States)

    Forstmann, Birte U; Isaacs, Bethany R; Temel, Yasin

    2017-10-01

    Deep brain stimulation (DBS) is a neurosurgical treatment for neurological disorders often planned with 1.5-T or 3-T MRI. The clinical efficacy of DBS can be improved using ultrahigh-field (UHF) MRI for planning by increasing the level of precision required for an individualized approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Laser-guided energetic discharges over large air gaps by electric-field enhanced plasma filaments

    OpenAIRE

    Th?berge, Francis; Daigle, Jean-Fran?ois; Kieffer, Jean-Claude; Vidal, Fran?ois; Ch?teauneuf?, Marc

    2017-01-01

    Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electr...

  19. 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...

  20. 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

  1. Field guide to Muddy Formation outcrops, Crook County, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Rawn-Schatzinger, V.

    1993-11-01

    The objectives of this research program are to (1) determine the reservoir characteristics and production problems of shoreline barrier reservoirs; and (2) develop methods and methodologies to effectively characterize shoreline bamer reservoirs to predict flow patterns of injected and produced fluids. Two reservoirs were selected for detailed reservoir characterization studies -- Bell Creek field, Carter County, Montana that produces from the Lower Cretaceous (Albian-Cenomanian) Muddy Formation, and Patrick Draw field, Sweetwater County, Wyoming that produces from the Upper Cretaceous (Campanian) Almond Formation of the Mesaverde Group. An important component of the research project was to use information from outcrop exposures of the producing formations to study the spatial variations of reservoir properties and the degree to which outcrop information can be used in the construction of reservoir models. This report contains the data and analyses collected from outcrop exposures of the Muddy Formation, located in Crook County, Wyoming, 40 miles south of Bell Creek oil field. The outcrop data set contains permeability, porosity, petrographic, grain size and geologic data from 1-inch-diameter core plugs chilled from the outcrop face, as well as geological descriptions and sedimentological interpretations of the outcrop exposures. The outcrop data set provides information about facies characteristics and geometries and the spatial distribution of permeability and porosity on interwell scales. Appendices within this report include a micropaleontological analyses of selected outcrop samples, an annotated bibliography of papers on the Muddy Formation in the Powder River Basin, and over 950 permeability and porosity values measured from 1-inch-diameter core plugs drilled from the outcrop. All data contained in this resort are available in electronic format upon request. The core plugs drilled from the outcrop are available for measurement.

  2. Kinetic physics in exhausts formed by guide field reconnection within the magnetosheath, as observed by MMS

    Science.gov (United States)

    Mistry, R.; Eastwood, J. P.; Phan, T.; Cassak, P.; Shay, M. A.; Haggerty, C. C.; Oieroset, M.; Goldman, M. V.; Giles, B. L.; Gershman, D. J.; Paterson, W. R.; Russell, C. T.; Lindqvist, P. A.; Ergun, R.; Torbert, R. B.; Burch, J. L.; Zhao, C.; Strangeway, R. J.

    2016-12-01

    MMS has allowed, for the first time, particle observations of reconnection to be made on ion and electron scales. These extremely high resolution measurements can be used to investigate the kinetic physics of reconnection that are known to be essential to the dissipation mechanisms at play in the diffusion region. Kinetic effects, however, are not limited to the diffusion region, and both simulations and observations have shown that kinetic processes can occur in the exhaust region downstream of the reconnection site. Whilst the primary targets of MMS are reconnection at the magnetopause and magnetotail, excursions of the spacecraft into the magnetosheath allow for observations in the less frequently accessible reconnection regime of symmetric reconnection with large guide fields. Here we present MMS observations of magnetosheath reconnection exhausts made approximately 75 ion inertial lengths downstream of the X-line. These exhausts are observed in the magnetosheath-proper, and as such have relatively symmetric inflow conditions. Furthermore, these exhausts have guide fields of a strength comparable to that of the reconnecting magnetic field. We use high resolution MMS observations of these events to study the effects of guide fields on the exhausts that form in symmetric reconnection. We find that non-uniform electron heating which occurs near the X-line in the presence of a guide field persists downstream, at least to the distance of these observations. Additionally, the electron velocity is resolved below the ion kinetic scale, where it is highly disrupted compared to the case of anti-parallel reconnection, with narrow field-aligned electron flows towards the X-line. These flows result in the generation of Hall currents and magnetic fields within the exhaust region itself, allowing Hall effects to persist beyond the ion diffusion region. The effects of the guide field on counter-streaming ion beams within the exhaust are also presented, as well as brief periods

  3. Investigation of the free electron laser with a guide magnetic field

    International Nuclear Information System (INIS)

    Kwan, T.; Dawson, J.M.

    1979-01-01

    The free electron laser with a static guide magnetic field has been investigated theoretically and by computer simulation using a fully relativistic electromagnetic particle code which has one spatial and three velocity dimensions. By passing a relativistic electron beam through a helical magnetic field, high frequency electromagnetic radiation is generated by its coupling to the negative energy electrostatic beam modes through the helical magnetic field. In the regime of strong guide field where Ω/sub c/e/γ>>k 0 v/sub 0z/, the dispersion relation is obtained by using a fluid model for the electron beam and the growth rates are solved for numerically. Reasonable agreement between the theory and the simulations has been obtained. It was found that the growth rate increases linearly with magnetic ripple strength but decreases with the strength of the guide field. In addition, the growth rates also increase slightly with the beam energy. For a reasonably strong guide field (e.g., Ω/sub c/e=6.0ω/sub p/e), the growth rate can be on the order of 0.1ω/sub p/e and the efficiency of radiation production has been found to be as high as 16%. However, the efficiency decreases with the strength of the guide field. A theory for the saturation level is developed which relates the efficiency to the continued growth of the electromagnetic wave after the onset of trapping by the electrostatic field. It is found that the growth continues for about one bounce time and the observed saturation levels are reasonably well explained

  4. 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

  5. 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

  6. Simulation and experimental study on transportation of dual-beam guided by confining magnetic-field

    International Nuclear Information System (INIS)

    Bai Xianchen; Zhang Jiande; Yang Jianhua

    2008-01-01

    Using external longitudinal magnetic-field to guide dual-beam out of the dual-shift tubes is a key step for the practicality of synchronizing dual-beam produced by a single accelerator. On the basis of the simulation of the confining magnetic-field for the solid dual-beam, the experiment of magnetic-field guiding annular dual-beam was presented. When the diode voltage was 380 kV, dual-beam currents of 5.10 kA and 4.92 kA were obtained. The experimental results indicate that the designed magnetic-field system could confine the annular dual-beam effectively, and the critical confining magnetic-field is about 0.5 T. (authors)

  7. Experimental verification of the role of electron pressure in fast magnetic reconnection with a guide field

    International Nuclear Information System (INIS)

    Fox, W.; Sciortino, F.; Stechow, A. von; Jara-Almonte, J.

    2017-01-01

    We report detailed laboratory observations of the structure of a reconnection current sheet in a two-fluid plasma regime with a guide magnetic field. We observe and quantitatively analyze the quadrupolar electron pressure variation in the ion-diffusion region, as originally predicted by extended magnetohydrodynamics simulations. The projection of the electron pressure gradient parallel to the magnetic field contributes significantly to balancing the parallel electric field, and the resulting cross-field electron jets in the reconnection layer are diamagnetic in origin. Furthermore, these results demonstrate how parallel and perpendicular force balance are coupled in guide field reconnection and confirm basic theoretical models of the importance of electron pressure gradients for obtaining fast magnetic reconnection.

  8. 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.

  9. 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.

  10. Geologic guide to the island of Hawaii: A field guide for comparative planetary geology

    Science.gov (United States)

    Greeley, R. (Editor)

    1974-01-01

    With geological data available for all inner planets except Venus, we are entering an era of true comparative planetary geology, when knowledge of the differences and similarities for classes of structures (e.g., shield volcanoes) will lead to a better understanding of general geological processes, regardless of planet. Thus, it is imperative that planetologists, particularly those involved in geological mapping and surface feature analysis for terrestrial planets, be familiar with volcanic terrain in terms of its origin, structure, and morphology. One means of gaining this experience is through field trips in volcanic terrains - hence, the Planetology Conference in Hawaii. In addition, discussions with volcanologists at the conference provide an important basis for establishing communications between the two fields that will facilitate comparative studies as more data become available.

  11. 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.

  12. 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.

  13. Field Test of the World Health Organization Multi-Professional Patient Safety Curriculum Guide

    Science.gov (United States)

    Farley, Donna; Zheng, Hao; Rousi, Eirini; Leotsakos, Agnès

    2015-01-01

    Introduction Although the importance of training in patient safety has been acknowledged for over a decade, it remains under-utilized and under-valued in most countries. WHO developed the Multi-professional Patient Safety Curriculum Guide to provide schools with the requirements and tools for incorporating patient safety in education. It was field tested with 12 participating schools across the six WHO regions, to assess its effectiveness for teaching patient safety to undergraduate and graduate students in a global variety of settings. Methods The evaluation used a combined prospective/retrospective design to generate formative information on the experiences of working with the Guide and summative information on the impacts of the Guide. Using stakeholder interviews and student surveys, data were gathered from each participating school at three times: the start of the field test (baseline), soon after each school started teaching, and soon after each school finished teaching. Results Stakeholders interviewed were strongly positive about the Guide, noting that it emphasized universally important patient safety topics, was culturally appropriate for their countries, and gave credibility and created a focus on patient safety at their schools. Student perceptions and attitudes regarding patient safety improved substantially during the field test, and their knowledge of the topics they were taught doubled, from 10.7% to 20.8% of correct answers on the student survey. Discussion This evaluation documented the effectiveness of the Curriculum Guide, for both ease of use by schools and its impacts on improving the patient safety knowledge of healthcare students. WHO should be well positioned to refine the contents of the Guide and move forward in encouraging broader use of the Guide globally for teaching patient safety. PMID:26406893

  14. Field Test of the World Health Organization Multi-Professional Patient Safety Curriculum Guide.

    Science.gov (United States)

    Farley, Donna; Zheng, Hao; Rousi, Eirini; Leotsakos, Agnès

    2015-01-01

    Although the importance of training in patient safety has been acknowledged for over a decade, it remains under-utilized and under-valued in most countries. WHO developed the Multi-professional Patient Safety Curriculum Guide to provide schools with the requirements and tools for incorporating patient safety in education. It was field tested with 12 participating schools across the six WHO regions, to assess its effectiveness for teaching patient safety to undergraduate and graduate students in a global variety of settings. The evaluation used a combined prospective/retrospective design to generate formative information on the experiences of working with the Guide and summative information on the impacts of the Guide. Using stakeholder interviews and student surveys, data were gathered from each participating school at three times: the start of the field test (baseline), soon after each school started teaching, and soon after each school finished teaching. Stakeholders interviewed were strongly positive about the Guide, noting that it emphasized universally important patient safety topics, was culturally appropriate for their countries, and gave credibility and created a focus on patient safety at their schools. Student perceptions and attitudes regarding patient safety improved substantially during the field test, and their knowledge of the topics they were taught doubled, from 10.7% to 20.8% of correct answers on the student survey. This evaluation documented the effectiveness of the Curriculum Guide, for both ease of use by schools and its impacts on improving the patient safety knowledge of healthcare students. WHO should be well positioned to refine the contents of the Guide and move forward in encouraging broader use of the Guide globally for teaching patient safety.

  15. 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.

  16. Magnetospheric Multiscale Observations of the Electron Diffusion Region of Large Guide Field Magnetic Reconnection

    Science.gov (United States)

    Eriksson, S.; Wilder, F. D.; Ergun, R. E.; Schwartz, S. J.; Cassak, P. A.; Burch, J. L.; Chen, Li-Jen; Torbert, R. B.; Phan, T. D.; Lavraud, B.; hide

    2016-01-01

    We report observations from the Magnetospheric Multiscale (MMS) satellites of a large guide field magnetic reconnection event. The observations suggest that two of the four MMS spacecraft sampled the electron diffusion region, whereas the other two spacecraft detected the exhaust jet from the event. The guide magnetic field amplitude is approximately 4 times that of the reconnecting field. The event is accompanied by a significant parallel electric field (E(sub parallel lines) that is larger than predicted by simulations. The high-speed (approximately 300 km/s) crossing of the electron diffusion region limited the data set to one complete electron distribution inside of the electron diffusion region, which shows significant parallel heating. The data suggest that E(sub parallel lines) is balanced by a combination of electron inertia and a parallel gradient of the gyrotropic electron pressure.

  17. Management and techniques for riparian restorations: roads field guide, vol. I

    Science.gov (United States)

    Roads/Riparian Restoration Team

    2002-01-01

    Improperly constructed or maintained roads near riparian and wetland areas may degrade these valuable sites. Degradation affects many aspects of the riparian and wetland ecosystems. This field guide presents information in a practical, user friendly format to help resource managers and professionals. Well-documented evaluation and monitoring strategies are critical in...

  18. Management and techniques for riparian restorations: roads field guide, vol. II

    Science.gov (United States)

    Roads/Riparian Restoration Team

    2002-01-01

    Improperly constructed or maintained roads near riparian and wetland areas may degrade these valuable sites. Degradation affects many aspects of the riparian and wetland ecosystems. This field guide presents information in a practical, user friendly format to help resource managers and professionals. Well-documented evaluation and monitoring strategies are critical in...

  19. Field Guide for Studying Classroom Events and Their Cultural Context. Indigenous Mathematics Project. Working Paper 4.

    Science.gov (United States)

    Levin, Paula; And Others

    This field guide was used as a basis for documenting classroom events at five community school sites in Papua New Guinea, as part of the Indigenous Mathematics Project in its ongoing research into primary mathematics learning. Methodology for evaluating the appropriateness of curriculum form and content is described and specific sections focus on…

  20. Trees of Laos and Vietnam: a field guide to 100 economically or ecologically important species

    NARCIS (Netherlands)

    Sam, Hoang Van; Nanthavong, Khamseng; Keßler, P.J.A.

    2004-01-01

    This field guide to 100 economically or ecologically important tree species from Laos and Vietnam enables the user to identify the included taxa with user-friendly keys. It includes scientific names, botanical descriptions of families, genera, and species. Specific information on distribution,

  1. A wave guide model of lightning currents and their electromagnetic field

    Science.gov (United States)

    Volland, H.

    1980-01-01

    Lightning channels are considered as resonant wave guides in which only standing resonant wave modes can be excited. Two types of discharging currents develop. Type 1 is an aperiodic wave; type 2 is a damped oscillation. The electromagnetic radiation field of both types of currents is calculated and compared with the observation.

  2. A guiding vector field algorithm for path following control of nonholonomic mobile robots

    NARCIS (Netherlands)

    Kapitaniuk, Iurii; Proskurnikov, Anton; Cao, Ming

    2018-01-01

    In this paper we propose an algorithm for path following control of the nonholonomic mobile robot based on the idea of the guiding vector field (GVF). The desired path may be an arbitrary smooth curve in its implicit form, that is, a level set of a predefined smooth function. Using this function and

  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. 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…

  5. 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…

  6. Field guide for the identification of snags and logs in the interior Columbia River basin.

    Science.gov (United States)

    Catherine G. Parks; Evelyn L. Bull; Torolf R. Torgersen

    1997-01-01

    This field guide contains descriptions and color photographs of snags and logs of 10 coniferous and 3 deciduous tree species found in the interior Columbia River basin. Methods arc described to distinguish among the different species when various amounts of branches, cones, and bark arc missing. Wildlife use of the different species of snags and logs are listed. Snags...

  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. Geologic field-trip guide to Medicine Lake Volcano, northern California, including Lava Beds National Monument

    Science.gov (United States)

    Donnelly-Nolan, Julie M.; Grove, Timothy L.

    2017-08-17

    Medicine Lake volcano is among the very best places in the United States to see and walk on a variety of well-exposed young lava flows that range in composition from basalt to rhyolite. This field-trip guide to the volcano and to Lava Beds National Monument, which occupies part of the north flank, directs visitors to a wide range of lava flow compositions and volcanic phenomena, many of them well exposed and Holocene in age. The writing of the guide was prompted by a field trip to the California Cascades Arc organized in conjunction with the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial meeting in Portland, Oregon, in August of 2017. This report is one of a group of three guides describing the three major volcanic centers of the southern Cascades Volcanic Arc. The guides describing the Mount Shasta and Lassen Volcanic Center parts of the trip share an introduction, written as an overview to the IAVCEI field trip. However, this guide to Medicine Lake volcano has descriptions of many more stops than are included in the 2017 field trip. The 23 stops described here feature a range of compositions and volcanic phenomena. Many other stops are possible and some have been previously described, but these 23 have been selected to highlight the variety of volcanic phenomena at this rear-arc center, the range of compositions, and for the practical reason that they are readily accessible. Open ground cracks, various vent features, tuffs, lava-tube caves, evidence for glaciation, and lava flows that contain inclusions and show visible evidence of compositional zonation are described and visited along the route.

  9. Apps for Angiosperms: The Usability of Mobile Computers and Printed Field Guides for UK Wild Flower and Winter Tree Identification

    Science.gov (United States)

    Stagg, Bethan C.; Donkin, Maria E.

    2017-01-01

    We investigated usability of mobile computers and field guide books with adult botanical novices, for the identification of wildflowers and deciduous trees in winter. Identification accuracy was significantly higher for wildflowers using a mobile computer app than field guide books but significantly lower for deciduous trees. User preference…

  10. Avian respiratory system disorders

    Science.gov (United States)

    Olsen, Glenn 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.

  11. Avian Influenza (Bird Flu)

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Subtypes Transmission of Avian Influenza A Viruses Between Animals and People Related Links Research Glossary of Influenza (Flu) Terms ...

  12. Safety and efficacy of an aroA-deleted live vaccine against avian colibacillosis in a multicentre field trial in broilers in Morocco.

    Science.gov (United States)

    Mombarg, Mark; Bouzoubaa, Khalid; Andrews, Stuart; Vanimisetti, Hima Bindu; Rodenberg, Jeff; Karaca, Kemal

    2014-01-01

    The safety and efficacy of an aroA-deleted live vaccine against avian colibacillosis (Poulvac(®) E. coli) was evaluated in broilers in a multicentre field trial. The trial sites consisted of 18 paired bird houses (randomly assigned to either the vaccination or the control treatment groups) located in 15 farms in three different regions of Morocco. A field dose of vaccine was administered on day of hatch by the spray route. Both clinical and performance parameters were compared between vaccinated and control groups, in which the experimental unit was defined as the individual bird house. No adverse reactions attributable to the vaccine were observed throughout the study. Non-inferiority of the vaccinated bird houses versus the control houses during a 2-week period post vaccination was statistically demonstrated for mortality and average daily weight gain. Vaccine efficacy was confirmed based on significant differences between vaccinated and unvaccinated groups measured for the full duration of the trial, including colibacillosis-like lesions observed at slaughter (1.7 versus 3.5%; P = 0.0054), total mortality (9.3 versus 10.3%; P = 0.0203), average daily weight gain (47.8 versus 46.2 g/day; P = 0.0006), average number of antibiotic treatment days (0.5 versus 2.0; P = 0.0008) and percentage of the birds that was marketed (90.0 versus 89.0%; P = 0.0309). In conclusion, the vaccine was demonstrated to be both safe and efficacious under field conditions.

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

    2011-08-02

    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

  14. 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, John 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

  15. Field-trip guides to selected volcanoes and volcanic landscapes of the western United States

    Science.gov (United States)

    ,

    2017-06-23

    The North American Cordillera is home to a greater diversity of volcanic provinces than any comparably sized region in the world. The interplay between changing plate-margin interactions, tectonic complexity, intra-crustal magma differentiation, and mantle melting have resulted in a wealth of volcanic landscapes.  Field trips in this guide book collection (published as USGS Scientific Investigations Report 2017–5022) visit many of these landscapes, including (1) active subduction-related arc volcanoes in the Cascade Range; (2) flood basalts of the Columbia Plateau; (3) bimodal volcanism of the Snake River Plain-Yellowstone volcanic system; (4) some of the world’s largest known ignimbrites from southern Utah, central Colorado, and northern Nevada; (5) extension-related volcanism in the Rio Grande Rift and Basin and Range Province; and (6) the eastern Sierra Nevada featuring Long Valley Caldera and the iconic Bishop Tuff.  Some of the field trips focus on volcanic eruptive and emplacement processes, calling attention to the fact that the western United States provides opportunities to examine a wide range of volcanological phenomena at many scales.The 2017 Scientific Assembly of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) in Portland, Oregon, was the impetus to update field guides for many of the volcanoes in the Cascades Arc, as well as publish new guides for numerous volcanic provinces and features of the North American Cordillera. This collection of guidebooks summarizes decades of advances in understanding of magmatic and tectonic processes of volcanic western North America. These field guides are intended for future generations of scientists and the general public as introductions to these fascinating areas; the hope is that the general public will be enticed toward further exploration and that scientists will pursue further field-based research.

  16. Laser-guided energetic discharges over large air gaps by electric-field enhanced plasma filaments.

    Science.gov (United States)

    Théberge, Francis; Daigle, Jean-François; Kieffer, Jean-Claude; Vidal, François; Châteauneuf, Marc

    2017-01-05

    Recent works on plasma channels produced during the propagation of ultrashort and intense laser pulses in air demonstrated the guiding of electric discharges along the laser path. However, the short plasma lifetime limits the length of the laser-guided discharge. In this paper, the conductivity and lifetime of long plasma channels produced by ultrashort laser pulses is enhanced efficiently over many orders of magnitude by the electric field of a hybrid AC-DC high-voltage source. The AC electric pulse from a Tesla coil allowed to stimulate and maintain the highly conductive channel during few milliseconds in order to guide a subsequent 500 times more energetic discharge from a 30-kV DC source. This DC discharge was laser-guided over an air gap length of two metres, which is more than two orders of magnitude longer than the expected natural discharge length. Long plasma channel induced by laser pulses and stimulated by an external high-voltage source opens the way for wireless and efficient transportation of energetic current pulses over long air gaps and potentially for guiding lightning.

  17. Avian Influenza in Birds

    Science.gov (United States)

    ... However, some ducks can be infected without any signs of illness. Top of Page Avian Influenza in Wild Birds Avian influenza A viruses have ... hours. Some ducks can be infected without any signs of illness. Avian influenza outbreaks are of concern in domesticated birds for ...

  18. Avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

  19. Moral, welfare and recreation : a financial management guide for the field activity comptroller.

    OpenAIRE

    Wenn, Patrick R.

    1992-01-01

    Approved for public release; distribution is unlimited. The focus of the thesis is to identify the functions and responsibilities of the Navy field activity comptroller, and to develop a comprehensive financial management guide of the Morale, Welfare and Recreation program. Specifically, the thesis examines the role of the comptroller in the distribution, management and budgeting of MWR funds, determines MWR comptroller requirements and offers useful-and practical recommendations to effect...

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

    Science.gov (United States)

    Estrada, Héctor; Rebling, Johannes; Razansky, Daniel

    2017-06-01

    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 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. We observed a skull-guided wave propagation over a lateral distance of at least 3 mm, with a half-decay length in the direction perpendicular to the skull ranging from 35 to 300 μm at 6 and 0.5 MHz, respectively. Propagation losses are mostly attributed to the heterogenous acoustic properties of the skull. It is generally anticipated that our findings may facilitate and broaden the application of ultrasound-mediated techniques in brain diagnostics and therapy.

  1. 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.

  2. Energy flux due to electromagnetic fluctuations during guide field magnetic reconnection

    International Nuclear Information System (INIS)

    Kuwahata, Akihiro; Inomoto, Michiaki; Ono, Yasushi; Yanai, Ryoma

    2016-01-01

    Large electromagnetic fluctuations inside the current sheet and large reconnection electric fields are observed during fast magnetic reconnection in the presence of a guide field. The fluctuations transport 2.5% of the dissipated magnetic energy from the reconnection region. Although the energy gains of the ions and electrons are approximately 60% and 12%, respectively, of the dissipated magnetic energy after the fast reconnection, the energy of fluctuations is not comparable to their energy gains. The fluctuations do not directly contribute to the energy conversion but might cause the fast reconnection leading to the rapid release of magnetic energy. (author)

  3. Impact of field number and beam angle on functional image-guided lung cancer radiotherapy planning

    Science.gov (United States)

    Tahir, Bilal A.; Bragg, Chris M.; Wild, Jim M.; Swinscoe, James A.; Lawless, Sarah E.; Hart, Kerry A.; Hatton, Matthew Q.; Ireland, Rob H.

    2017-09-01

    To investigate the effect of beam angles and field number on functionally-guided intensity modulated radiotherapy (IMRT) normal lung avoidance treatment plans that incorporate hyperpolarised helium-3 magnetic resonance imaging (3He MRI) ventilation data. Eight non-small cell lung cancer patients had pre-treatment 3He MRI that was registered to inspiration breath-hold radiotherapy planning computed tomography. IMRT plans that minimised the volume of total lung receiving  ⩾20 Gy (V20) were compared with plans that minimised 3He MRI defined functional lung receiving  ⩾20 Gy (fV20). Coplanar IMRT plans using 5-field manually optimised beam angles and 9-field equidistant plans were also evaluated. For each pair of plans, the Wilcoxon signed ranks test was used to compare fV20 and the percentage of planning target volume (PTV) receiving 90% of the prescription dose (PTV90). Incorporation of 3He MRI led to median reductions in fV20 of 1.3% (range: 0.2-9.3% p  =  0.04) and 0.2% (range: 0 to 4.1%; p  =  0.012) for 5- and 9-field arrangements, respectively. There was no clinically significant difference in target coverage. Functionally-guided IMRT plans incorporating hyperpolarised 3He MRI information can reduce the dose received by ventilated lung without comprising PTV coverage. The effect was greater for optimised beam angles rather than uniformly spaced fields.

  4. 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...

  5. Field-trip guide to a volcanic transect of the Pacific Northwest

    Science.gov (United States)

    Geist, Dennis; Wolff, John; Harpp, Karen

    2017-08-01

    The Pacific Northwest region of the United States provides world-class and historically important examples of a wide variety of volcanic features. This guide is designed to give a broad overview of the region’s diverse volcanism rather than focusing on the results of detailed studies; the reader should consult the reference list for more detailed information on each of the sites, and we have done our best to recognize previous field trip leaders who have written the pioneering guides. This trip derives from one offered as a component of the joint University of Idaho- Washington State University volcanology class taught from 1995 through 2014, and it borrows in theme from the classic field guide of Johnston and Donnelly-Nolan (1981). For readers interested in using this field guide as an educational tool, we have included an appendix with supplemental references to resources that provide useful background information on relevant topics, as well as a few suggestions for field-based exercises that could be useful when bringing students to these locations in the future. The 4-day trip begins with an examination of lava flow structures of the Columbia River Basalt, enormous lava fields that were emplaced during one of the largest eruptive episodes in Earth’s recent history. On the second day, the trip turns to the High Lava Plains, a bimodal volcanic province that transgressed from southeast to northwest from the Miocene through the Holocene, at the northern margin of the Basin and Range Province. This volcanic field provides excellent examples of welded ignimbrite, silicic lavas and domes, monogenetic basaltic lava fields, and hydrovolcanic features. The third day is devoted to a circumnavigation of Crater Lake, the result of one of the world’s best-documented caldera-forming eruptions. The caldera walls also expose the anatomy of Mount Mazama, a stratovolcano of the Cascade Range. The last day is spent at Newberry Volcano, a back-arc shield volcano topped by a

  6. Painful shoulder? Remote clinical management of a Field Guide with shoulder pain and loss of shoulder function in Antarctica

    Directory of Open Access Journals (Sweden)

    Gareth Jones

    2017-06-01

    Full Text Available We report the case of a female Field Guide based at the British Antarctic Survey’s Rothera Science Research Station on Adelaide Island, Antarctica who independently contacted a physiotherapist specialising in climbing related injuries (GJ located in the UK. for a second opinion. The Field Guide was experiencing significant work difficulties due to shoulder pain and subsequent loss of function particularly in overhead activities. The case raises important issues about the medical management of Field Guides operating in extreme environments and remote locations

  7. Italian field survey reveals a high diffusion of avian metapneumovirus subtype B in layers and weaknesses in the vaccination strategy applied.

    Science.gov (United States)

    Cecchinato, Mattia; Lupini, Caterina; Ricchizzi, Enrico; Falchieri, Marco; Meini, Amelio; Jones, Richard C; Catelli, Elena

    2012-12-01

    The current information on the prevalence of avian metapneumovirus (aMPV) infection in layers is fragmentary and its true impact on egg production often remains unknown or unclear. In order to draw an epidemiologic picture of aMPV presence in layer flocks in Italy, a survey was performed on 19 flocks of pullets and layers based on longitudinal studies or sporadic samplings. aMPV was detected by reverse transcription (RT)-PCR, and blood samples were collected for serology by aMPV ELISA. Occurrences of respiratory signs and a drop in egg production were recorded. Possible involvement of infectious bronchitis (IB) and egg drop syndrome (EDS) viruses that could have caused loss of egg production we ruled out for IB virus by RT-PCR, and EDS virus was ruled out by hemagglutination-inhibition (HI). Only subtype B of aMPV was found in both pullet and layer farms. Surveys of pullets showed that most groups became infected prior to the onset of lay without showing clear respiratory signs. At the point of lay, these groups were serologically positive to aMPV. In two layer flocks, egg drops were observed and could be strongly linked to the presence of aMPV infection. Results were correlated with aMPV vaccination programs applied to the birds in three flocks on the same farm. Only a vaccination program which included two live and one killed vaccines gave complete protection from aMPV infection to the birds, while a single live vaccine application was not efficacious. The current study gives an inside view of field aMPV diffusion in Italy and its control in layers.

  8. Hamiltonian field description of two-dimensional vortex fluids and guiding center plasmas

    International Nuclear Information System (INIS)

    Morrison, P.J.

    1981-03-01

    The equations that describe the motion of two-dimensional vortex fluids and guiding center plasmas are shown to possess underlying field Hamiltonian structure. A Poisson bracket which is given in terms of the vorticity, the physical although noncanonical dynamical variable, casts these equations into Heisenberg form. The Hamiltonian density is the kinetic energy density of the fluid. The well-known conserved quantities are seen to be in involution with respect to this Poisson bracket. Expanding the vorticity in terms of a Fourier-Dirac series transforms the field description given here into the usual canonical equations for discrete vortex motion. A Clebsch potential representation of the vorticity transforms the noncanonical field description into a canonical description

  9. Overview for geologic field-trip guides to volcanoes of the Cascades Arc in northern California

    Science.gov (United States)

    Muffler, L. J. Patrick; Donnelly-Nolan, Julie M.; Grove, Timothy L.; Clynne, Michael A.; Christiansen, Robert L.; Calvert, Andrew T.; Ryan-Davis, Juliet

    2017-08-15

    The California Cascades field trip is a loop beginning and ending in Portland, Oregon. The route of day 1 goes eastward across the Cascades just south of Mount Hood, travels south along the east side of the Cascades for an overview of the central Oregon volcanoes (including Three Sisters and Newberry Volcano), and ends at Klamath Falls, Oregon. Day 2 and much of day 3 focus on Medicine Lake Volcano. The latter part of day 3 consists of a drive south across the Pit River into the Hat Creek Valley and then clockwise around Lassen Volcanic Center to the town of Chester, California. Day 4 goes from south to north across Lassen Volcanic Center, ending at Burney, California. Day 5 and the first part of day 6 follow a clockwise route around Mount Shasta. The trip returns to Portland on the latter part of day 6, west of the Cascades through the Klamath Mountains and the Willamette Valley. Each of the three sections of this guidebook addresses one of the major volcanic regions: Lassen Volcanic Center (a volcanic field that spans the volcanic arc), Mount Shasta (a fore-arc stratocone), and Medicine Lake Volcano (a rear-arc, shield-shaped edifice). Each section of the guide provides (1) an overview of the extensive field and laboratory studies, (2) an introduction to the literature, and (3) directions to the most important and accessible field localities. The field-trip sections contain far more stops than can possibly be visited in the actual 6-day 2017 IAVCEI excursion from Portland. We have included extra stops in order to provide a field-trip guide that will have lasting utility for those who may have more time or may want to emphasize one particular volcanic area.

  10. CAROLINE MANIAQUE-BENTON, WITH MEREDITH GAGLIO (ed.: WHOLE EARTH FIELD GUIDE

    Directory of Open Access Journals (Sweden)

    Laurent Baridon

    2016-05-01

    Full Text Available RESUMEN The Whole Earth Field Guide edited by Caroline Maniaque-Benton with Meredith Gaglio, is a selection of texts cited as « suggested reading » in the Stewart Brand's Whole Earth Catalog published around 1970. Precisely documented, a substantial introduction gives to the reader fascinating informations about this publication and its founder. This catalog was a cultural touchstone for million of readers looking for informations about self construction, yurt design, juicers, underground radio, but also about Buckminster Fuller, Victor Papanek, Lewis Mumford, Paul Ehrlich, Frei Otto, Ant Farm, Marshal McLuhan, Robert Crumb... and many others.

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

    International Nuclear Information System (INIS)

    De Seze, Rene; Courtin, Claude; Gruet, Pierre; Becker, Thierry; Demaret, Philippe; Donati, Patrice; Ganem, Yael; Moureaux, Patrick; Bisseriex, Christian; Bonnet, Christian; Cabaret, Philippe; Castro, Helene; Laurent, Pierre; Le Berre, Guy; Marteau, Emmanuel; Tirlemont, Stephane

    2013-01-01

    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

  12. Motion of guiding center drift atoms in the electric and magnetic field of a Penning trap

    International Nuclear Information System (INIS)

    Kuzmin, S.G.; O'Neil, T.M.

    2005-01-01

    The ApparaTus for High precision Experiment on Neutral Antimatter and antihydrogen TRAP collaborations have produced antihydrogen atoms by recombination in a cryogenic antiproton-positron plasma. This paper discusses the motion of the weakly bound atoms in the electric and magnetic field of the plasma and trap. The effective electric field in the moving frame of the atom polarizes the atom, and then gradients in the field exert a force on the atom. An approximate equation of motion for the atom center of mass is obtained by averaging over the rapid internal dynamics of the atom. The only remnant of the atom internal dynamics that enters this equation is the polarizability for the atom. This coefficient is evaluated for the weakly bound and strongly magnetized (guiding center drift) atoms understood to be produced in the antihydrogen experiments. Application of the approximate equation of motion shows that the atoms can be trapped radially in the large space charge field near the edge of the positron column. Also, an example is presented for which there is full three-dimensional trapping, not just radial trapping. Even untrapped atoms follow curved trajectories, and such trajectories are discussed for the important class of atoms that reach a field ionization diagnostic. Finally, the critical field for ionization is determined as an upper bound on the range of applicability of the theory

  13. On guided circumferential waves in soft electroactive tubes under radially inhomogeneous biasing fields

    Science.gov (United States)

    Wu, Bin; Su, Yipin; Chen, Weiqiu; Zhang, Chuanzeng

    2017-02-01

    Soft electroactive (EA) tube actuators and many other cylindrical devices have been proposed recently in literature, which show great advantages over those made from conventional hard solid materials. However, their practical applications may be limited because these soft EA devices are prone to various failure modes. In this paper, we present an analysis of the guided circumferential elastic waves in soft EA tube actuators, which has potential applications in the in-situ nondestructive evaluation (NDE) or online structural health monitoring (SHM) to detect structural defects or fatigue cracks in soft EA tube actuators and in the self-sensing of soft EA tube actuators based on the concept of guided circumferential elastic waves. Both circumferential SH and Lamb-type waves in an incompressible soft EA cylindrical tube under inhomogeneous biasing fields are considered. The biasing fields, induced by the application of an electric voltage difference to the electrodes on the inner and outer cylindrical surfaces of the EA tube in addition to an axial pre-stretch, are inhomogeneous in the radial direction. Dorfmann and Ogden's theory of nonlinear electroelasticity and the associated linear theory for small incremental motion constitute the basis of our analysis. By means of the state-space formalism for the incremental wave motion along with the approximate laminate technique, dispersion relations are derived in a particularly efficient way. For a neo-Hookean ideal dielectric model, the proposed approach is first validated numerically. Numerical examples are then given to show that the guided circumferential wave propagation characteristics are significantly affected by the inhomogeneous biasing fields and the geometrical parameters. Some particular phenomena such as the frequency veering and the nonlinear dependence of the phase velocity on the radial electric voltage are discussed. Our numerical findings demonstrate that it is feasible to use guided circumferential

  14. Self-guiding of high-intensity laser pulses for laser wake field acceleration

    International Nuclear Information System (INIS)

    Umstader, D.; Liu, X.

    1992-01-01

    A means of self-guiding an ultrashort and high-intensity laser pulse is demonstrated both experimentally and numerically. Its relevance to the laser wake field accelerator concept is discussed. Self-focusing and multiple foci formation are observed when a high peak power (P>100 GW), 1 μm, subpicosecond laser is focused onto various gases (air or hydrogen). It appears to result from the combined effects of self-focusing by the gas, and de-focusing both by diffraction and the plasma formed in the central high-intensity region. Quasi-stationary computer simulations show the same multiple foci behavior as the experiments. The results suggest much larger nonlinear electronic susceptibilities of a gas near or undergoing ionization in the high field of the laser pulse. Although self-guiding of a laser beam by this mechanism appears to significantly extend its high-intensity focal region, small-scale self-focusing due to beam non-uniformity is currently a limitation

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

    International Nuclear Information System (INIS)

    Frias, B.; Alonso, J.; Dwinell, R.; Lothrop, F.

    1989-01-01

    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

  16. A practical guide to in vivo proton magnetic resonance spectroscopy at high magnetic fields.

    Science.gov (United States)

    Xin, Lijing; Tkáč, Ivan

    2017-07-15

    Localized proton magnetic resonance spectroscopy ( 1 H-MRS) is a noninvasive tool for measuring in vivo neurochemical information in animal and human brains. With the increase of magnetic field strength, whereas localized 1 H-MRS benefits from higher sensitivity and spectral dispersion, it is challenged by increased spatial inhomogeneity of the B 0 and B 1 fields, larger chemical shift displacement error, and shortened T 2 relaxation times of metabolites. Advanced localized 1 H-MRS methodologies developed for high magnetic fields have shown promising results and allow the measurement of neurochemical profiles with up to 19 brain metabolites, including less-abundant metabolites, such as glutathione, glycine, γ-aminobutyric acid and ascorbate. To provide a practical guide for conducting in vivo 1 H-MRS studies at high magnetic field strength, we reviewed various essential technical aspects from data acquisition (hardware requirements, B 1 and B 0 inhomogeneity, water suppression, localization sequences and acquisition strategies) to data processing (frequency and phase correction, spectral quality control, spectral fitting and concentration referencing). Additionally, we proposed guidelines for choosing the most appropriate data acquisition and processing approaches to maximize the achievable neurochemical information. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Notes from the field: Highly pathogenic avian influenza A (H7N3) virus infection in two poultry workers--Jalisco, Mexico, July 2012.

    Science.gov (United States)

    2012-09-14

    During June-August 2012, Mexico's National Service for Health, Safety, and Food Quality reported outbreaks of highly pathogenic avian influenza (HPAI) A (H7N3) virus in poultry on farms throughout the state of Jalisco. This report describes two cases of conjunctivitis without fever or respiratory symptoms caused by HPAI A (H7N3) virus infection in humans associated with exposure to infected poultry.

  18. Overview for geologic field-trip guides to Mount Mazama, Crater Lake Caldera, and Newberry Volcano, Oregon

    Science.gov (United States)

    Bacon, Charles R.; Donnelly-Nolan, Julie M.; Jensen, Robert A.; Wright, Heather M.

    2017-08-16

    These field-trip guides were written for the occasion of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial scientific assembly in Portland, Oregon, in August 2017. The guide to Mount Mazama and Crater Lake caldera is an updated and expanded version of the guide (Bacon, 1989) for part of an earlier IAVCEI trip to the southern Cascade Range. The guide to Newberry Volcano describes the stops included in the 2017 field trip. Crater Lake and Newberry are the two best-preserved and most recent calderas in the Cascades Volcanic Arc. Although located in different settings in the arc, with Crater Lake on the arc axis and Newberry in the rear-arc, both volcanoes are located at the intersection of the arc and the northwest corner region of the extensional Basin and Range Province.

  19. Student representation of magnetic field concepts in learning by guided inquiry

    International Nuclear Information System (INIS)

    Fatmaryanti, Siska Desy; Suparmi; Sarwanto; Ashadi

    2017-01-01

    The purpose of this study was to determine the change of student’s representation after the intervention of learning by guided inquiry. The population in this research were all students who took a fundamental physics course, consisted of 28 students academic year 2016, Department of Physics Education, Faculty of Teacher Training and Education, University of Muhammadiyah Purworejo. This study employed a quasi-experimental design with group pre-test and post-test. The result of the research showed that the average of students representation of magnetic field before implementation of guided inquiry was 28,6 % and after implementation was 71,4%. It means that the student’s ability of multi-representation increase. Moreover, the number of students who is able to write and draw based on experiment data increased from 10,7% to 21,4 %. It was also showed that the number of student with no answer decreased from 28,5% to 10,7%. (paper)

  20. Compensated Row-Column Ultrasound Imaging System Using Multilayered Edge Guided Stochastically Fully Connected Random Fields.

    Science.gov (United States)

    Ben Daya, Ibrahim; Chen, Albert I H; Shafiee, Mohammad Javad; Wong, Alexander; Yeow, John T W

    2017-09-06

    The row-column method received a lot of attention for 3-D ultrasound imaging. By reducing the number of connections required to address the 2-D array and therefore reducing the amount of data to handle, this addressing method allows for real time 3-D imaging. Row-column still has its limitations: the issues of sparsity, speckle noise inherent to ultrasound, the spatially varying point spread function, and the ghosting artifacts inherent to the row-column method must all be taken into account when building a reconstruction framework. In this research, we build on a previously published system and propose an edge-guided, compensated row-column ultrasound imaging system that incorporates multilayered edge-guided stochastically fully connected conditional random fields to address the limitations of the row-column method. Tests carried out on simulated and real row-column ultrasound images show the effectiveness of our proposed system over other published systems. Visual assessment show our proposed system's potential at preserving edges and reducing speckle. Quantitative analysis shows that our proposed system outperforms previously published systems when evaluated with metrics such as Peak Signal-to-Noise Ratio, Coefficient of Correlation, and Effective Number of Looks. These results show the potential of our proposed system as an effective tool for enhancing 3-D row-column imaging.

  1. Depolarization per bounce of ultracold neutrons in collision with material guides within varying ambient magnetic holding fields

    Science.gov (United States)

    Dearmitt, Damien; Chakrabarty, Sanjay; Holley, A. T.

    2017-09-01

    Material depolarization of `ultracold' neutrons (UCN), neutrons with energies of 100 neV, is studied to understand and control systematic effects in experiments where polarized UCN interact with materials, such as polarized beta-decay experiments. A number of `PPM Depol' experiments have been performed by the Los Alamos National Lab UCN team to test the probability of depolarization per bounce of UCN within material test guides. In one of these experiments, different guides were mounted within a varying ambient longitudinal holding field adjustable from 10G to 260G, which allowed the measurement to be repeated with different holding field strengths. Following analysis of the data from this experiment, Monte Carlo simulations were used to investigate systematic effects associated with poorly-constrained properties of the experiment, such as guide specularity and guide loss per bounce, and the UCN energy spectrum. The method of analysis as well as extracted depolarization probabilities per bounce for copper guides of various surface preparations and stainless steel guides, all as a function of holding field strength, will be presented. Comparisons between simulations and data will also be used to discuss systematic effects present in the analysis. Supported by NSF Grant 1553861.

  2. Effect of Guide Field in Localization of Whistler Wave and Turbulent Spectrum in Magnetic Reconnection Sites

    Science.gov (United States)

    Pathak, N.; Sharma, R. P.; Uma, R.

    2017-12-01

    Whistler waves have ample of observations in the magnetosphere near the dayside magnetopause. Also, the role of whistler waves is well established in the context of magnetic reconnection as well as turbulence generation. In the present work, we examine the combined effect of guide field and nonlinearity in the development of turbulence in magnetic reconnection sites. We have derived the dynamical equation of 3D whistler wave propagating through Harris sheet assuming that background number density and background field are perturbed. The nonlinear dynamical equation is then solved numerically using pseudo spectral method and finite difference method. Simulation results represent the nonlinear evolution of X-O field line in the presence of nonlinearity, which causes the generation of turbulence. When the system reaches quasi steady state, we have evaluated power spectrum in magnetopause and it shows two different scaling having k-3/2 at larger saclesand k-3 at smaller scales. Energy distribution at smaller scales leads to the formation of thermal tail of energetic particles. The energy of these electrons is also calculated and comes out to be in the order of 100 keV.

  3. Impact of compressibility and a guide field on Fermi acceleration during magnetic island coalescence

    Science.gov (United States)

    Montag, Peter; Egedal, Jan; Lichko, Emily; Wetherton, Blake

    2017-10-01

    Previous work has shown that Fermi acceleration can be an effective heating mechanism during magnetic island coalescence, where electrons may undergo repeated reflections as the magnetic field lines contract. This energization has the potential to account for the power-law distributions of particle energy inferred from observations of solar flares. Here, we develop a generalized framework for the analysis of Fermi acceleration that can incorporate the effects of compressibility and non-uniformity along field lines, which have commonly been neglected in previous treatments of the problem. Applying this framework to the simplified case of the uniform flux tube allows us to find both the power-law scaling of the distribution function and the rate at which the power-law behavior develops. We find that a guide magnetic field of order unity effectively suppresses the development of power-law distributions. The work was supported by NASA Grant No. NNX14AC68G, NSF GEM Grant No. 1405166, NSF Award 1404166, and NASA Award NNX15AJ73G.

  4. Field dose radiation determination by active learning with Gaussian Process for autonomous robot guiding

    International Nuclear Information System (INIS)

    Freitas Naiff, Danilo de; Silveira, Paulo R.; Pereira, Claudio M.N.A.

    2017-01-01

    This article proposes an approach for determination of radiation dose pro le in a radiation-susceptible environment, aiming to guide an autonomous robot in acting on those environments, reducing the human exposure to dangerous amount of dose. The approach consists of an active learning method based on information entropy reduction, using log-normally warped Gaussian Process (GP) as surrogate model, resulting in non-linear online regression with sequential measurements. Experiments with simulated radiation dose fields of varying complexity were made, and results showed that the approach was effective in reconstruct the eld with high accuracy, through relatively few measurements. The technique was also shown some robustness in presence measurement noise, present in real measurements, by assuming Gaussian noise. (author)

  5. Field dose radiation determination by active learning with Gaussian Process for autonomous robot guiding

    Energy Technology Data Exchange (ETDEWEB)

    Freitas Naiff, Danilo de; Silveira, Paulo R.; Pereira, Claudio M.N.A., E-mail: danilonai1992@poli.ufrj.br, E-mail: paulo@lmp.ufrj.br, E-mail: cmnap@ien.gov.br [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil); Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-11-01

    This article proposes an approach for determination of radiation dose pro le in a radiation-susceptible environment, aiming to guide an autonomous robot in acting on those environments, reducing the human exposure to dangerous amount of dose. The approach consists of an active learning method based on information entropy reduction, using log-normally warped Gaussian Process (GP) as surrogate model, resulting in non-linear online regression with sequential measurements. Experiments with simulated radiation dose fields of varying complexity were made, and results showed that the approach was effective in reconstruct the eld with high accuracy, through relatively few measurements. The technique was also shown some robustness in presence measurement noise, present in real measurements, by assuming Gaussian noise. (author)

  6. The IEEE guide to writing in the engineering and technical fields

    CERN Document Server

    Kmiec, David

    2017-01-01

    This book introduces students and practicing engineers to all the components of writing in the workplace. It teaches readers how considerations of audience and purpose govern the structure of their documents within particular work settings. The IEEE Guide to Writing in the Engineering and Technical Fields is broken up into two sections: "Writing in Engineering Organizations" and "What Can You Do With Writing?" The first section helps readers approach their writing in a logical and persuasive way as well as analyze their purpose for writing. The second section demonstrates how to distinguish rhetorical situations and the generic forms to inform, train, persuade, and collaborate. The emergence of the global workplace has brought with it an increasingly important role for effective technical communication. Engineers more often need to work in cross-functional teams with people in different disciplines, in different countries, and in different parts of the world. Engineers must know how to communicate in a rapid...

  7. Field evaluation of unlighted overhead guide signs using older drivers : executive summary report.

    Science.gov (United States)

    2003-08-01

    Problem: In the preceding Unlighted Overhead Guide : Sign Feasibility Study, it was determined that : the lighting of overhead guide signs on : freeways could be eliminated if white : microprismatic Type VII or Type IX legends : were used on green be...

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

    International Nuclear Information System (INIS)

    Barisas, S.; Polich, J.; Surles, T.; Habegger, L.; Anderson, D.; Opelka, J.; Frangos, T.

    1985-03-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Barisas, S.; Polich, J.; Surles, T.; Habegger, L.; Anderson, D.; Opelka, J.; Frangos, T.

    1985-03-01

    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.

  10. Field-trip guide to the geologic highlights of Newberry Volcano, Oregon

    Science.gov (United States)

    Jensen, Robert A.; Donnelly-Nolan, Julie M.

    2017-08-09

    Newberry Volcano and its surrounding lavas cover about 3,000 square kilometers (km2) in central Oregon. This massive, shield-shaped, composite volcano is located in the rear of the Cascades Volcanic Arc, ~60 km east of the Cascade Range crest. The volcano overlaps the northwestern corner of the Basin and Range tectonic province, known locally as the High Lava Plains, and is strongly influenced by the east-west extensional environment. Lava compositions range from basalt to rhyolite. Eruptions began about half a million years ago and built a broad composite edifice that has generated more than one caldera collapse event. At the center of the volcano is the 6- by 8-km caldera, created ~75,000 years ago when a major explosive eruption of compositionally zoned tephra led to caldera collapse, leaving the massive shield shape visible today. The volcano hosts Newberry National Volcanic Monument, which encompasses the caldera and much of the northwest rift zone where mafic eruptions occurred about 7,000 years ago. These young lava flows erupted after the volcano was mantled by the informally named Mazama ash, a blanket of volcanic ash generated by the eruption that created Crater Lake about 7,700 years ago. This field trip guide takes the visitor to a variety of easily accessible geologic sites in Newberry National Volcanic Monument, including the youngest and most spectacular lava flows. The selected sites offer an overview of the geologic story of Newberry Volcano and feature a broad range of lava compositions. Newberry’s most recent eruption took place about 1,300 years ago in the center of the caldera and produced tephra and lava of rhyolitic composition. A significant mafic eruptive event occurred about 7,000 years ago along the northwest rift zone. This event produced lavas ranging in composition from basalt to andesite, which erupted over a distance of 35 km from south of the caldera to Lava Butte where erupted lava flowed west to temporarily block the Deschutes

  11. DIVA vaccination strategies for avian influenza virus.

    Science.gov (United States)

    Suarez, David L

    2012-12-01

    Vaccination for both low pathogenicity avian influenza and highly pathogenic avian influenza is commonly used by countries that have become endemic for avian influenza virus, but stamping-out policies are still common for countries with recently introduced disease. Stamping-out policies of euthanatizing infected and at-risk flocks has been an effective control tool, but it comes at a high social and economic cost. Efforts to identify alternative ways to respond to outbreaks without widespread stamping out has become a goal for organizations like the World Organisation for Animal Health. A major issue with vaccination for avian influenza is trade considerations because countries that vaccinate are often considered to be endemic for the disease and they typically lose their export markets. Primarily as a tool to promote trade, the concept of DIVA (differentiate infected from vaccinated animals) has been considered for avian influenza, but the goal for trade is to differentiate vaccinated and not-infected from vaccinated and infected animals because trading partners are unwilling to accept infected birds. Several different strategies have been investigated for a DIVA strategy, but each has advantages and disadvantages. A review of current knowledge on the research and implementation of the DIVA strategy will be discussed with possible ways to implement this strategy in the field. The increased desire for a workable DIVA strategy may lead to one of these ideas moving from the experimental to the practical.

  12. Proton beam deflection in MRI fields: Implications for MRI-guided proton therapy.

    Science.gov (United States)

    Oborn, B M; Dowdell, S; Metcalfe, P E; Crozier, S; Mohan, R; Keall, P J

    2015-05-01

    This paper investigates, via magnetic modeling and Monte Carlo simulation, the ability to deliver proton beams to the treatment zone inside a split-bore MRI-guided proton therapy system. Field maps from a split-bore 1 T MRI-Linac system are used as input to geant4 Monte Carlo simulations which model the trajectory of proton beams during their paths to the isocenter of the treatment area. Both inline (along the MRI bore) and perpendicular (through the split-bore gap) orientations are simulated. Monoenergetic parallel and diverging beams of energy 90, 195, and 300 MeV starting from 1.5 and 5 m above isocenter are modeled. A phase space file detailing a 2D calibration pattern is used to set the particle starting positions, and their spatial location as they cross isocenter is recorded. No beam scattering, collimation, or modulation of the proton beams is modeled. In the inline orientation, the radial symmetry of the solenoidal style fringe field acts to rotate the protons around the beam's central axis. For protons starting at 1.5 m from isocenter, this rotation is 19° (90 MeV) and 9.8° (300 MeV). A minor focusing toward the beam's central axis is also seen, but only significant, i.e., 2 mm shift at 150 mm off-axis, for 90 MeV protons. For the perpendicular orientation, the main MRI field and near fringe field act as the strongest to deflect the protons in a consistent direction. When starting from 1.5 m above isocenter shifts of 135 mm (90 MeV) and 65 mm (300 MeV) were observed. Further to this, off-axis protons are slightly deflected toward or away from the central axis in the direction perpendicular to the main deflection direction. This leads to a distortion of the phase space pattern, not just a shift. This distortion increases from zero at the central axis to 10 mm (90 MeV) and 5 mm (300 MeV) for a proton 150 mm off-axis. In both orientations, there is a small but subtle difference in the deflection and distortion pattern between protons fired parallel to the

  13. MR-guided liver tumor ablation employing open high-field 1.0T MRI for image-guided brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Ricke, Jens; Thormann, Markus; Ludewig, Matthias; Jungnickel, Kerstin; Grosser, Oliver; Wybranski, Christian; Fischbach, Frank [Universitaetsklinikum Magdeburg AoeR, Klinik fuer Radiologie und Nuklearmedizin, Magdeburg (Germany); Peters, Nils; Hass, Peter [Universitaetsklinikum Magdeburg AoeR, Klinik fuer Strahlentherapie, Magdeburg (Germany); Bunke, Juergen [Philips Healthcare, Hamburg (Germany)

    2010-08-15

    To determine the feasibility and safety of image-guided brachytherapy employing a modified open high-field MR system. This is a follow-up study of a development project enabling technologies for interventional use of 1.0T open MRI. Modifications included coils and in-bore visualization, fluoroscopic sequences and user interfaces. We recruited 104 patients with 224 liver malignancies to receive MR-guided brachytherapy. Interventions were performed >20 min after Gd-EOB-DTPA. We recorded interventional parameters including the intervention time (from acquisition of the first scout until the final sequence for brachytherapy treatment planning). Two reviewers assessed MR-fluoroscopic images in comparison to plain CT as used in CT intervention, applying a rating scale of 1-10. Statistical analysis included Friedman and Kendall's W tests. We employed freehand puncture with interactive dynamic imaging for navigation. Technical success rate was 218 complete ablations in 224 tumours (97%). The median intervention time was 61 min. We recorded no adverse events related to the use of MRI. No major complications occurred. The rate of minor complications was 4%. Local control at 3 months was 96%. Superiority of MR-fluoroscopic, Gd-EOB-DTPA-enhanced images over plain CT was highly significant (P < 0.001). MR-guided brachytherapy employing open high-field MRI is feasible and safe. (orig.)

  14. Book Review - Field Estimation of Soil Water Content: A Practical Guide to Methods, Instrumentation and Sensor Technology

    Science.gov (United States)

    Field Estimation of Soil Water Content delves into the workings of a number of devices that measure soil water content. The authors aimed the book as a guide to help readers find the soil water measuring devices that perform best under given circumstances; then they give readers information on how t...

  15. Dynamic Instructional Leadership to Support Student Learning and Development: The Field Guide to Comer Schools in Action

    Science.gov (United States)

    Joyner, Edward T., Ed.; Ben-Avie, Michael, Ed.; Comer, James P., Ed.

    2004-01-01

    Schools are the only universally accessible institutions where there are enough adults to provide continuous support for children's growth, development, and success in life. Using the process pioneered by renowned child psychiatrist Dr. James P. Comer and his colleagues at the Yale School Development Program (SDP), this unique field guide offers…

  16. A field guide for forest indicator plants, sensitive plants, and noxious weeds of the Shoshone National Forest, Wyoming

    Science.gov (United States)

    Kent E. Houston; Walter J. Hartung; Carol J. Hartung

    2001-01-01

    This field guide was designed for people with minimal botanical training. It is an identification aid to plant species that have ecological indicator value, are on sensitive species lists, or are considered noxious weeds. It contains illustrations and simplified taxonomic descriptions.

  17. Relationships among vegetation structure, canopy composition, and avian richness patterns across an aspen-conifer forest gradient

    Science.gov (United States)

    Charles E. Swift; Kerri T. Vierling; Andrew T. Hudak; Lee A. Vierling

    2017-01-01

    Ecologists have a long-term interest in understanding the relative influence of vegetation composition and vegetation structure on avian diversity. LiDAR remote sensing is useful in studying local patterns of avian diversity because it characterizes fine-scale vegetation structure across broad extents. We used LiDAR, aerial and satellite imagery, and avian field data...

  18. Geologic field-trip guide to Mount Shasta Volcano, northern California

    Science.gov (United States)

    Christiansen, Robert L.; Calvert, Andrew T.; Grove, Timothy L.

    2017-08-18

    off, in a field of high-alumina olivine tholeiite lavas (HAOTs, referred to elsewhere in this guide as low-potassium olivine tholeiites, LKOTs). It proceeds around the southern, western, and northern flanks of Mount Shasta and onto a part of the arc axis. The stops feature elements of the Mount Shasta area in an approximately chronological order, from oldest to youngest.

  19. Field-trip guide to Mount Hood, Oregon, highlighting eruptive history and hazards

    Science.gov (United States)

    Scott, William E.; Gardner, Cynthia A.

    2017-06-22

    This guidebook describes stops of interest for a geological field trip around Mount Hood volcano. It was developed for the 2017 International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Scientific Assembly in Portland, Oregon. The intent of this guidebook and accompanying contributions is to provide an overview of Mount Hood, including its chief geologic processes, magmatic system, eruptive history, local tectonics, and hazards, by visiting a variety of readily accessible localities. We also describe coeval, largely monogenetic, volcanoes in the region. Accompanying the field-trip guidebook are separately authored contributions that discuss in detail the Mount Hood magmatic system and its products and behavior (Kent and Koleszar, this volume); Mount Hood earthquakes and their relation to regional tectonics and the volcanic system (Thelen and Moran, this volume); and young surface faults cutting the broader Mount Hood area whose extent has come to light after acquisition of regional light detection and ranging coverage (Madin and others, this volume).The trip makes an approximately 175-mile (280-kilometer) clockwise loop around Mount Hood, starting and ending in Portland. The route heads east on Interstate 84 through the Columbia River Gorge National Scenic Area. The guidebook points out only a few conspicuous features of note in the gorge, but many other guides to the gorge are available. The route continues south on the Mount Hood National Scenic Byway on Oregon Route 35 following Hood River, and returns to Portland on U.S. Highway 26 following Sandy River. The route traverses rocks as old as the early Miocene Eagle Creek Formation and overlying Columbia River Basalt Group of middle Miocene age, but chiefly lava flows and clastic products of arc volcanism of late Miocene to Holocene age.

  20. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... outbreaks in poultry have seriously impacted livelihoods, the economy and international trade in affected countries. Other avian influenza A( ... outbreaks in poultry have seriously impacted livelihoods, the economy and international trade in affected countries. Other avian influenza A( ...

  1. Genetic applications in avian conservation

    Science.gov (United States)

    Haig, Susan M.; Bronaugh, Whitcomb M.; Crowhurst, Rachel S.; D'Elia, Jesse; Eagles-Smith, Collin A.; Epps, Clinton W.; Knaus, Brian; Miller, Mark P.; Moses, Michael L.; Oyler-McCance, Sara; Robinson, W. Douglas; Sidlauskas, Brian

    2011-01-01

    A fundamental need in conserving species and their habitats is defining distinct entities that range from individuals to species to ecosystems and beyond (Table 1; Ryder 1986, Moritz 1994, Mayden and Wood 1995, Haig and Avise 1996, Hazevoet 1996, Palumbi and Cipriano 1998, Hebert et al. 2004, Mace 2004, Wheeler et al. 2004, Armstrong and Ball 2005, Baker 2008, Ellis et al. 2010, Winker and Haig 2010). Rapid progression in this interdisciplinary field continues at an exponential rate; thus, periodic updates on theory, techniques, and applications are important for informing practitioners and consumers of genetic information. Here, we outline conservation topics for which genetic information can be helpful, provide examples of where genetic techniques have been used best in avian conservation, and point to current technical bottlenecks that prevent better use of genomics to resolve conservation issues related to birds. We hope this review will provide geneticists and avian ecologists with a mutually beneficial dialogue on how this integrated field can solve current and future problems.

  2. MiDAS Field Guide – a Comprehensive Online Source of Information About the Microbes of Activated Sludge

    DEFF Research Database (Denmark)

    Nierychlo, Marta; McIlroy, Simon Jon; Saunders, Aaron Marc

    their morphology, diversity, physiology and distribution. It has proven very useful for studies of key processes such as nitrification/denitrification, biological phosphorus removalas well as investigations of poor flocculation and settling (bulking). Currently we are continuing our efforts to establish universal...... guide to the microbes of activated sludge by comparing microbial community composition in 32 WWTPs located worldwide. This will facilitate a better understanding of the ecology of the ecosystem of activated sludge. Reference: McIlroy et al. MiDAS: the field guide to the microbes of activated sludge...

  3. Geologic field trip guide to Mount Mazama and Crater Lake Caldera, Oregon

    Science.gov (United States)

    Bacon, Charles R.; Wright, Heather M.

    2017-08-08

    geologic research at Crater Lake have been incorporated not only in scientific investigations elsewhere, but also in the practical evaluation of local hazards (Bacon and others, 1997b) and geothermal resources (Bacon and Nathenson, 1996). The 1:24,000-scale geologic map of Mount Mazama and Crater Lake caldera (Bacon, 2008) is unusual because it portrays bedrock (outcrop), surficial, and lake floor geology. Caldera wall geology is depicted in detail on the accompanying geologic panoramas, and bedrock geology is shown in a 1:50,000-scale geologic map. This field guide supersedes earlier geology guides of Crater Lake (Bacon, 1987, 1989).

  4. Energization and Transport in 3D Kinetic Simulations of MMS Magnetopause Reconnection Site Encounters with Varying Guide Fields

    Science.gov (United States)

    Le, A.; Daughton, W. S.; Ohia, O.; Chen, L. J.; Liu, Y. H.

    2017-12-01

    We present 3D fully kinetic simulations of asymmetric reconnection with plasma parameters matching MMS magnetopause diffusion region crossings with varying guide fields of 0.1 [Burch et al., Science (2016)], 0.4 [Chen et al. JGR (2017)], and 1 [Burch and Phan, GRL (2016] of the reconnecting sheath field. Strong diamagnetic drifts across the magnetopause current sheet drive lower-hybrid drift instabilities (LHDI) over a range of wavelengths [Daughton, PoP (2003); Roytershteyn et al., PRL (2012)] that develop into a turbulent state. Magnetic field tracing diagnostics are employed to characterize the turbulent magnetic geometry and to evaluate the global reconnection rate. The contributions to Ohm's law are evaluated field line by field line, including time-averaged diagnostics that allow the quantification of anomalous resistivity and viscosity. We examine how fluctuating electric fields and chaotic magnetic field lines contribute to particle mixing across the separatrix, and we characterize the accelerated electron distributions that form under varying magnetic shear or guide field. The LHDI turbulence is found to strongly enhance transport and parallel electron heating in 3D compared to 2D, particularly along the magnetospheric separatrix [Le et al., GRL (2017)]. The PIC simulation results are compared to MMS observations.

  5. 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...... this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits....

  6. Invasive Plants Field and Reference Guide: An Ecological Perspective of Plant Invaders of Forests and Woodlands

    Science.gov (United States)

    Cynthia Huebner; Cassandra Olson; Heather Smith

    2005-01-01

    There are many field guides available about invasive plants and their identification. The purpose of this particular field guide is to give a scientific synthesis of what is known about the behavior of such species in managed, disturbed, and pristine forested systems in addition to key information for accurate identifi...

  7. Light Field Compression with Disparity Guided Sparse Coding based on Structural Key Views.

    Science.gov (United States)

    Chen, Jie; Hou, Junhui; Chau, Lap-Pui

    2017-09-08

    Recent imaging technologies are rapidly evolving for sampling richer and more immersive representations of the 3D world. One of the emerging technologies is light field (LF) cameras based on micro-lens arrays. To record the directional information of the light rays, a much larger storage space and transmission bandwidth are required by a LF image as compared with a conventional 2D image of similar spatial dimension. Hence, the compression of LF data becomes a vital part of its application. In this paper, we propose a LF codec with disparity guided Sparse Coding over a learned perspective-shifted LF dictionary based on selected Structural Key Views (SC-SKV). The sparse coding is based on a limited number of optimally selected SKVs; yet the entire LF can be recovered from the coding coefficients. By keeping the approximation identical between encoder and decoder, only the residuals of the non-key views, disparity map and the SKVs need to be compressed into the bit stream. An optimized SKV selection method is proposed such that most LF spatial information can be preserved. To achieve optimum dictionary efficiency, the LF is divided into several coding regions, over which the reconstruction works individually. Experiments and comparisons have been carried out over benchmark LF dataset, which show that the proposed SC-SKV codec produces convincing compression results in terms of both rate-distortion performance and visual quality compared with JEM (Joint Exploration Model): with 37.9% BD-rate reduction and 1.17 dB BD-PSNR improvement achieved on average, especially with up to 6 dB improvement for low bit rate scenarios.

  8. 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

  9. Nonlinear theory of a free electron laser with a helical wiggler and an axial guide magnetic field

    Directory of Open Access Journals (Sweden)

    N. S. Ginzburg

    2013-09-01

    Full Text Available A 1D nonlinear theory of a free electron laser (FEL with a helical wiggler and an axial guide magnetic field is developed based on averaged equations of the electron motion. By averaging we separated two different cases of the e-beam/rf-wave interaction. The first one corresponds to the traditional wiggler synchronism (resonance of rf wave with the electrons moving along stationary helical trajectories. The second one corresponds to combination resonances distinguishing by excitation of oscillation of the electrons near the stationary helical trajectory. Comparative analysis of the FEL operation in different regimes has been studied under the traditional wiggler synchronism condition. It was shown that FELs operated far from cyclotron resonance (including a reversed guide field orientation possess low sensitivity to the initial velocity spread in the driving beam resulting in high electron efficiency. In contrast, under the weak guide field (the gyrofrequency is less than the bounce frequency of a conventional orientation, the FEL efficiency is restricted by a significant increase in the transverse velocity of the electrons during the interaction with the rf wave that results in violation of the synchronism conditions and is accompanied by electron current losses. An additional mechanism of FEL efficiency enhancement under the conventional guide field orientation in the conditions when the gyrofrequency is higher than the bounce frequency, based on the dependence of the effective mass of the oscillating electrons on their energy, was demonstrated. Results of the theoretical analysis are compared with the results of experimental studies of FEL oscillators. The specific features of energy extraction from the electron beam under condition of an abnormal Doppler effect in the case of the combination resonance are described. This regime is beneficial to increase radiation frequency keeping wiggler period and electron energies.

  10. Field estimation of the flock-level diagnostic specificity of an enzyme-linked immunosorbent assay for Avian metapneumovirus antibodies in turkeys.

    Science.gov (United States)

    Muñoz-Zanzi, Claudia; Trampel, Darrell; Hanson, Tim; Harrison, Kristen; Goyal, Sagar; Cortinas, Roberto; Lauer, Dale

    2009-03-01

    Routine serologic testing for Avian metapneumovirus (AMPV) infection of turkey flocks at slaughter is currently being used to monitor changes in the occurrence of AMPV infection in endemic areas and can also be used to detect the emergence of infection in currently unaffected areas. Because of the costs associated with false-positive results, particularly in areas that are free of AMPV infection, there is a need to obtain improved estimates of flock-level specificity (SP). The objective of this study was to estimate flock-level SP of a program to monitor AMPV infection in turkey flocks at processing using a standard enzyme-linked immunosorbent assay (ELISA). A study was carried out in which 37 AMPV-free flocks from 7 Midwest operations were followed serologically. Six percent, 3%, and 0.2% of total samples tested AMPV positive at 8 weeks, 12 weeks, and at processing, respectively. Overall, flock-level SP increased as the cutoff increased and as age increased. Flock-level SP at processing was 97%, if a cutoff of 1 was used (the flock was classified as positive if at least 1 sample tested positive), and 100%, if any other cutoff was used. Administration of antibiotics (P = 0.02) and vaccination for Bordetella avium (P = 0.08) were positively associated with the probability of (false) positive test results. These findings suggest possible cross-reactions with other infections and highlight the need to consider variable diagnostic performance depending on farm conditions.

  11. Optimum Tilt Angle of Flow Guide in Steam Turbine Exhaust Hood Considering the Effect of Last Stage Flow Field

    Science.gov (United States)

    CAO, Lihua; LIN, Aqiang; LI, Yong; XIAO, Bin

    2017-07-01

    Heat transfer and vacuum in condenser are influenced by the aerodynamic performance of steam turbine exhaust hood. The current research on exhaust hood is mainly focused on analyzing flow loss and optimal design of its structure without consideration of the wet steam condensing flow and the exhaust hood coupled with the front and rear parts. To better understand the aerodynamic performance influenced by the tilt angle of flow guide inside a diffuser, taking a 600 MW steam turbine as an example, a numerical simulator CFX is adopted to solve compressible three-dimensional (3D) Reynolds time-averaged N-S equations and standard k- ɛ turbulence model. And the exhaust hood flow field influenced by different tilt angles of flow guide is investigated with consideration of the wet steam condensing flow and the exhaust hood coupled with the last stage blades and the condenser throat. The result shows that the total pressure loss coefficient and the static pressure recovery coefficient of exhaust hood change regularly and monotonously with the gradual increase of tilt angle of flow guide. When the tilt angle of flow guide is within the range of 30° to 40°, the static pressure recovery coefficient is in the range of 15.27% to 17.03% and the total pressure loss coefficient drops to approximately 51%, the aerodynamic performance of exhaust hood is significantly improved. And the effective enthalpy drop in steam turbine increases by 0.228% to 0.274%. It is feasible to obtain a reasonable title angle of flow guide by the method of coupling the last stage and the condenser throat to exhaust hood in combination of the wet steam model, which provides a practical guidance to flow guide transformation and optimal design in exhaust hood.

  12. Status of Avian Research at the National Renewable Energy Laboratory

    International Nuclear Information System (INIS)

    Sinclair, K.

    2001-01-01

    As the use of wind energy expands across the United States, concerns about the impacts of commercial wind farms on bird and bat populations are frequently raised. Two primary areas of concern are (1) possible litigation resulting from the killing of even one bird if it is protected by the Migratory Bird Treaty Act, the Endangered Species Act, or both; and (2) the effect of avian mortality on bird populations. To properly address these concerns, the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) supports scientifically based avian/wind power interaction research. In this paper I describe NREL's field-based research projects and summarize the status of the research. I also summarize NREL's other research activities, including lab-based vision research to increase the visibility of moving turbine blades and avian acoustic research, as well as our collaborative efforts with the National Wind Coordinating Committee's Avian Subcommittee

  13. Field guide to the woody plants of Taita hills, Kenya | Thijs | Journal ...

    African Journals Online (AJOL)

    , a list with endemic plant species, the multiple benefits the forests provide, additional references and a manual to use this guide. The second part contains identification keys that allow the reader to find the correct scientific name based on ...

  14. 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)

  15. Solar Energy Education. Home economics: teacher's guide. Field test edition. [Includes glossary

    Energy Technology Data Exchange (ETDEWEB)

    1981-06-01

    An instructional aid is provided for home economics teachers who wish to integrate the subject of solar energy into their classroom activities. This teacher's guide was produced along with the student activities book for home economics by the US Department of Energy Solar Energy Education. A glossary of solar energy terms is included. (BCS)

  16. 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),

  17. 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, finally......, a rounded air-hole one, which better describes the real fiber transverse section. Results have shown.the presence of anti-crossing points in the effective index curves associated with the transition of the guided mode to a surface mode. Moreover, it has been verified that these surface modes are responsible...

  18. 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.

  19. 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)

  20. 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...

  1. Field Guide to Layered Rocks. Earth Science Curriculum Project Pamphlet Series PS-3.

    Science.gov (United States)

    Freeman, Tom

    Presented is the study of sequences of rock layers as the basis for historical geology. Also considered is the influence of rock layers on the appearance of the landscape. Specific relevant laws of geology are presented. Preparation for a field trip is discussed. An example field trip is discussed and field techniques and projects are reviewed.…

  2. Cranial radiotherapy guided by computed tomography with or without fields conformation in pediatric

    International Nuclear Information System (INIS)

    Fernandez, Diego; Caussa, Lucas; Murina, Patricia; Zunino, Silvia

    2007-01-01

    Many malignancies in children can be cured by radiotherapy, acute toxicity and the significant effect of delayed treatment are worrying for the patient, family and society. Therefore, the end of the pediatric radiotherapy is to maintain or improve the cure rate of cancer, diminishing the aftermath of treatment. The goal of this study is to measure differences in doses to the healthy tissue of the central nervous system with two radiotherapy techniques, both guided by computed tomography [es

  3. species diversity of dry season avian fauna in kano, nigeria 418

    African Journals Online (AJOL)

    userpc

    frequency of birds seen. However, the Zoological garden in particular, had significant effect on frequencies of birds (P<0.05). Key Words: Avian, Birds, Diversity, Kano, Nigeria. INTRODUCTION. The general purpose of most avian field studies is to estimate how many species of a given taxon or group of taxa occur in an area.

  4. Avian influenza surveillance and diagnosis

    Science.gov (United States)

    Rapid detection and accurate identification of low (LPAI) and high pathogenicity avian influenza (HPAI) is critical to controlling infections and disease in poultry. Test selection and algorithms for the detection and diagnosis of avian influenza virus (AIV) in poultry may vary somewhat among differ...

  5. Avian and human metapneumovirus.

    Science.gov (United States)

    Broor, Shobha; Bharaj, Preeti

    2007-04-01

    Pneumovirus infection remains a significant problem for both human and veterinary medicine. Both avian pneumovirus (aMPV, Turkey rhinotracheitis virus) and human metapneumovirus (hMPV) are pathogens of birds and humans, which are associated with respiratory tract infections. Based on their different genomic organization and low level of nucleotide (nt) and amino acid (aa) identity with paramyxoviruses in the genus Pneumovirus, aMPV and hMPV have been classified into a new genus referred to as Metapneumovirus. The advancement of our understanding of pneumovirus biology and pathogenesis of pneumovirus disease in specific natural hosts can provide us with strategies for vaccine formulations and combined antiviral and immunomodulatory therapies.

  6. Coherent and incoherent radiation from free-electron lasers with an axial guide field

    OpenAIRE

    Freund, Henry P.; Sprangle, P.; Dillenburg, Darcy; Jornada, Eda Homrich da; Liberman, Bernardo; Schneider, Ruth de Souza

    1981-01-01

    The spontaneous and induced emission from a free-electron laser is treated for the case in which an axial magnetic field is imposed in addition to the helical, axially periodic wiggler magnetic field. The classes of possible single-particle trajectories in this configuration are discussed, and the results are applied to a calculation of the incoherent radiation from a beam of relativistic electrons in the system. The coherent radiation is treated by solving the Vlasov-Maxwell equations for th...

  7. Avian influenza in birds and mammals.

    Science.gov (United States)

    Cardona, Carol J; Xing, Zheng; Sandrock, Christian E; Davis, Cristina E

    2009-07-01

    The disease syndromes caused by avian influenza viruses are highly variable depending on the host species infected, its susceptibility and response to infection and the virulence of the infecting viral strain. Although avian influenza viruses have a broad host range in general, it is rare for an individual strain or subtype to infect more than one species. The H5N1 highly pathogenic avian influenza virus (HPAIV) lineages of viruses that descended from A/goose/Guandong/96 (H5N1 HPAIV) are unusual in the diversity of species they have infected worldwide. Although the species affected by H5N1 HPAI in the field and those that have been experimentally studied are diverse, their associated disease syndromes are remarkably similar across species. In some species, multi-organ failure and death are rapid and no signs of the disease are observed. Most prominently in this category are chickens and other avian species of the order Galliformes. In other species, neurologic signs develop resulting in the death of the host. This is what has been reported in domestic cats (Carnivora), geese (Anseriformes), ratites (Struthioniformes), pigeons inoculated with high doses (Columbiformes) and ducks infected with H5N1 HPAIV isolated since 2002 (Anseriformes). In some other species, the disease is more prolonged and although multi-organ failure and death are the eventual outcomes, the signs of disease are more extensive. Predominantly, these species include humans (Primates) and the laboratory models of human disease, the ferret (Carnivora), mouse (Rodentia) and cynamologous macaques (Primates). Finally, some species are more resistant to infection with H5N1 HPAIV and show few or no signs of disease. These species include pigeons in some studies (Columbiformes), ducks inoculated with pre-2002 isolates (Anseriformes), and pigs (Artiodactyla).

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

    NARCIS (Netherlands)

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

    2016-01-01

    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

  9. 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.

  10. Electric-Field-Guided Precision Manipulation of Catalytic Nanomotors for Cargo Delivery and Powering Nanoelectromechanical Devices.

    Science.gov (United States)

    Guo, Jianhe; Gallegos, Jeremie June; Tom, Ashley Robyn; Fan, Donglei

    2018-02-27

    We report a controllable and precision approach in manipulating catalytic nanomotors by strategically applied electric (E-) fields in three dimensions (3-D). With the high controllability, the catalytic nanomotors have demonstrated versatility in capturing, delivering, and releasing of cargos to designated locations as well as in situ integration with nanomechanical devices (NEMS) to chemically power the actuation. With combined AC and DC E-fields, catalytic nanomotors can be accurately aligned by the AC E-fields and effectively change their speeds instantly by the DC E-fields. Within the 3-D orthogonal microelectrode sets, the in-plane transport of catalytic nanomotors can be swiftly turned on and off, and these catalytic nanomotors can also move in the vertical direction. The interplaying nanoforces that govern the propulsion and alignment are investigated. The modeling of catalytic nanomotors proposed in previous works has been confirmed quantitatively here. Finally, the prowess of the precision manipulation of catalytic nanomotors by E-fields is demonstrated in two applications: the capture, transport, and release of cargos to prepatterned microdocks, and the assembly of catalytic nanomotors on NEMS to power the continuous rotation. The concepts and approaches reported in this work could further advance applications of catalytic nanomotors, e.g., for assembling and powering nanomachines, nanorobots, and complex NEMS devices.

  11. Avian Primordial Germ Cells.

    Science.gov (United States)

    Tagami, Takahiro; Miyahara, Daichi; Nakamura, Yoshiaki

    2017-01-01

    Germ cells transmit genetic information to the next generation through gametogenesis. Primordial germ cells (PGCs) are the first germ-cell population established during development, and are the common origins of both oocytes and spermatogonia. Unlike in other species, PGCs in birds undergo blood circulation to migrate toward the genital ridge, and are one of the major biological properties of avian PGCs. Germ cells enter meiosis and arrest at prophase I during embryogenesis in females, whereas in males they enter mitotic arrest during embryogenesis and enter meiosis only after birth. In chicken, gonadal sex differentiation occurs as early as embryonic day 6, but meiotic initiation of female germ cells starts from a relatively late stage (embryonic day 15.5). Retinoic acid controls meiotic entry in developing chicken gonads through the expressions of retinaldehyde dehydrogenase 2, a major retinoic acid synthesizing enzyme, and cytochrome P450 family 26, subfamily B member 1, a major retinoic acid-degrading enzyme. The other major biological property of avian PGCs is that they can be propagated in vitro for the long term, and this technique is useful for investigating proliferation mechanisms. The main factor involved in chicken PGC proliferation is fibroblast growth factor 2, which activates the signaling of MEK/ERK and thus promotes the cell cycle and anti-apoptosis. Furthermore, the activation of PI3K/Akt signaling is indispensable for the proliferation and survival of chicken PGCs.

  12. 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.…

  13. 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)

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

    International Nuclear Information System (INIS)

    Qin, H.; Guan, X.

    2008-01-01

    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.

  15. A practical guide to manuscript writing with particular relevance to the field of pediatric hospital medicine.

    Science.gov (United States)

    Teufel, Ronald J; Andrews, Anne L; Williams, Derek J

    2014-11-01

    Publishing manuscripts in peer-reviewed journals, such as Hospital Pediatrics, is critical for both the academic development of practitioners in pediatric hospital medicine and the scientific advancement of our field. Understanding the purpose of scientific writing and developing a structured approach to the writing process is essential. Doing so will improve the clarity of your work and likely the ease at which your research is published and disseminated throughout the scientific community. The purposes of this article are to detail the structure of a scientific manuscript, to highlight specific writing strategies, and to provide writing tips that may help or hinder publication. Our ultimate goal is to advance the field of pediatric hospital medicine and its growing membership by promoting the dissemination of high-quality research. Copyright © 2014 by the American Academy of Pediatrics.

  16. Percutaneous image-guided cryoablation: current applications and results in the oncologic field.

    Science.gov (United States)

    Cazzato, Roberto Luigi; Garnon, Julien; Ramamurthy, Nitin; Koch, Guillaume; Tsoumakidou, Georgia; Caudrelier, Jean; Arrigoni, Francesco; Zugaro, Luigi; Barile, Antonio; Masciocchi, Carlo; Gangi, Afshin

    2016-12-01

    Percutaneous imaging-guided cryoablation (PICA) is a recently developed technique, which applies extreme hypothermia to destroy tumours under close imaging surveillance. It is minimally invasive, safe, repeatable, and does not interrupt or compromise other oncologic therapies. It presents several advantages over more established heat-based thermal ablation techniques (e.g. radiofrequency ablation; RFA) including intrinsic analgesic properties, superior monitoring capability on multi-modal imaging, ability to treat larger tumours, and preservation of tissue collagenous architecture. There has been a recent large increase in reports evaluating the utility of PICA in a wide range of patients and tumours, but systematic analysis of the literature is challenging due to the rapid pace of change and predominance of extensively heterogeneous level III studies. The precise onco-therapeutic role of PICA has not been established. This narrative review outlines the available evidence for PICA in a range of tumours. Current indications include curative therapy of small T1a renal tumours; curative/palliative therapy of small primary/secondary lung tumours where RFA is unsuitable; palliation of painful bone metastases; and urologic treatment of organ-confined prostate cancer. There is growing evidence to support its use for small hepatic tumours, and encouraging results have been obtained for breast tumours, extra-abdominal desmoid tumours, and management of higher-stage tumours and oligometastatic disease. However, the overall evidence base is weak, effectively restricting PICA to cases where standard therapy and RFA are unsuitable. As the technique and evidence continue to mature, the benefits of this emerging technique will hopefully become more widely available to cancer patients in the future.

  17. The anatomy and physiology of the avian endocrine system.

    Science.gov (United States)

    Ritchie, Midge; Pilny, Anthony A

    2008-01-01

    The endocrine system of birds is comparable to that of mammals, although there are many unique aspects to consider when studying the anatomy, physiology, and biochemistry. Avian endocrinology is a field of veterinary medicine that is unfamiliar to many practitioners; however, it is important to have a comprehensive understanding when evaluating companion birds in clinical practice. This article covers the anatomy and physiology of the normal avian, and readers are referred to other articles for a more detailed explanation of altered physiology and pathology.

  18. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... consultations Fact sheets Fact files Questions & answers Features Multimedia Contacts Influenza (Avian and other zoonotic) Fact sheet ... respiratory tract infection (fever and cough), early sputum production and rapid progression to severe pneumonia, sepsis with ...

  19. Genome Modification Technologies and Their Applications in Avian Species

    Directory of Open Access Journals (Sweden)

    Hong Jo Lee

    2017-10-01

    Full Text Available The rapid development of genome modification technology has provided many great benefits in diverse areas of research and industry. Genome modification technologies have also been actively used in a variety of research areas and fields of industry in avian species. Transgenic technologies such as lentiviral systems and piggyBac transposition have been used to produce transgenic birds for diverse purposes. In recent years, newly developed programmable genome editing tools such as transcription activator-like effector nuclease (TALEN and clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated protein 9 (CRISPR/Cas9 have also been successfully adopted in avian systems with primordial germ cell (PGC-mediated genome modification. These genome modification technologies are expected to be applied to practical uses beyond system development itself. The technologies could be used to enhance economic traits in poultry such as acquiring a disease resistance or producing functional proteins in eggs. Furthermore, novel avian models of human diseases or embryonic development could also be established for research purposes. In this review, we discuss diverse genome modification technologies used in avian species, and future applications of avian biotechnology.

  20. Adaptive optics for fluorescence wide-field microscopy using spectrally independent guide star and markers.

    Science.gov (United States)

    Vermeulen, Pierre; Muro, Eleonora; Pons, Thomas; Loriette, Vincent; Fragola, Alexandra

    2011-07-01

    We describe the implementation and use of an adaptive optics loop in the imaging path of a commercial wide field microscope. We show that it is possible to maintain the optical performances of the original microscope when imaging through aberrant biological samples. The sources used for illuminating the adaptive optics loop are spectrally independent, in excitation and emission, from the sample, so they do not appear in the final image, and their use does not contribute to the sample bleaching. Results are compared with equivalent images obtained with an identical microscope devoid of adaptive optics system.

  1. A field map guided approach to non-rigid registration of brain EPI to structural MRI

    Science.gov (United States)

    Gholipour, Ali; Kehtarnavaz, Nasser; Briggs, Richard W.; Gopinath, Kaundinya S.

    2007-03-01

    It is known that along the phase encoding direction the effect of magnetic field inhomogeneity causes significant spatial distortions in fast functional MRI Echo Planar Imaging (EPI). In this work, our previously developed distortion correction technique via a non-rigid registration of EPI to anatomical MRI is improved by adding information from field maps to achieve a more accurate and efficient registration. Local deformation models are used in regions of distortion artifacts instead of using a global non-rigid transformation. The use of local deformations not only enhances the efficiency of the non-rigid registration by reducing the number of deformation model parameters, but also provides constraints to avoid physically incorrect deformations in undistorted regions. The accuracy and reliability of the non-rigid registration technique is improved by using an additional high-resolution gradient echo EPI scan. In-vivo validation is performed by comparing the similarity of the low-resolution EPI to various structural MRI scans before and after applying the computed deformation models. Visual inspection of the images, as well as Mutual Information (MI) and Normalized Cross Correlation (NCC) comparisons, reveal improvements within the sub-voxel range in the moderately distorted areas but not in the signal loss regions.

  2. Geologic field-trip guide to the volcanic and hydrothermal landscape of the Yellowstone Plateau

    Science.gov (United States)

    Morgan Morzel, Lisa Ann; Shanks, W. C. Pat; Lowenstern, Jacob B.; Farrell, Jamie M.; Robinson, Joel E.

    2017-11-20

    Yellowstone National Park, a nearly 9,000 km2 (~3,468 mi2) area, was preserved in 1872 as the world’s first national park for its unique, extraordinary, and magnificent natural features. Rimmed by a crescent of older mountainous terrain, Yellowstone National Park has at its core the Quaternary Yellowstone Plateau, an undulating landscape shaped by forces of late Cenozoic explosive and effusive volcanism, on-going tectonism, glaciation, and hydrothermal activity. The Yellowstone Caldera is the centerpiece of the Yellowstone Plateau. The Yellowstone Plateau lies at the most northeastern front of the 17-Ma Yellowstone hot spot track, one of the few places on Earth where time-transgressive processes on continental crust can be observed in the volcanic and tectonic (faulting and uplift) record at the rate and direction predicted by plate motion. Over six days, this field trip presents an intensive overview into volcanism, tectonism, and hydrothermal activity on the Yellowstone Plateau (fig. 1). Field stops are linked directly to conceptual models related to monitoring of the various volcanic, geochemical, hydrothermal, and tectonic aspects of the greater Yellowstone system. Recent interest in young and possible future volcanism at Yellowstone as well as new discoveries and synthesis of previous studies, (for example, tomographic, deformation, gas, aeromagnetic, bathymetric, and seismic surveys), provide a framework in which to discuss volcanic, hydrothermal, and seismic activity in this dynamic region.

  3. Early Avian Research at the Savannah River Site: Historical Highlights and Possibilities for the Future

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, J.M.; Odum, E.P.

    2000-10-01

    Avian biology was a major component of early research and baseline surveys. The focus of research shifted and the SRS evolved from open fields to forest cover. In the early years avian species richness and abundance increased with successional age of the vegetation from old-field to forest. During the early years resident game birds increased. More recent studies will help to understand the role of habitat in local and regional extinctions. A variety of survey techniques is needed.

  4. Functional window of the avian compass.

    Science.gov (United States)

    Poonia, Vishvendra Singh; Kondabagil, Kiran; Saha, Dipankar; Ganguly, Swaroop

    2017-05-01

    The functional window is an experimentally observed property of the avian compass that refers to its selectivity around the geomagnetic-field strength. We show that the simple radical-pair model, using biologically feasible hyperfine parameters, can qualitatively explain the salient features of the avian compass as observed in behavioral experiments: its functional window, as well as disruption of the compass action by radio-frequency fields of specific frequencies. Further, we show that adjustment of the hyperfine parameters can tune the functional window, suggesting a possible mechanism for its observed adaptation to field variation. While these lend support to the radical-pair model, we find that in its simplest form-or even with minor augmentations-it cannot quantitatively explain the observed width of the functional window. This suggests deeper generalization of the model, possibly in terms of more nuclei or more subtle environmental interaction than has been considered hitherto. Finally, we examine a possible biological purpose for the functional window; even assuming evolutionary benefit from radical-pair magnetoreception, it seems likely that the functional window could be just a corollary thereof, imparting no additional advantage.

  5. 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

  6. 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

  7. Field guide to malformations of frogs and toads: with radiographic interpretations

    Science.gov (United States)

    Meteyer, Carol U.

    2000-01-01

    In 1995, students found numerous malformed frogs on a field trip to a Minnesota pond. Since that time, reports of malformed frogs have increased dramatically. Malformed frogs have now been reported in 44 states in 38 species of frogs, and 19 species of toads. Estimates as high as 60% of the newly metamorphosed frog populations have had malformations at some ponds (NARCAM, ’99). The wide geographic distribution of malformed frogs and the variety of malformations are a concern to resource managers, research scientists and public health officials. The potential for malformations to serve as a signal of ecosystem disruption, and the affect this potential disruption might have on other organisms that share those ecosystems, has not been resolved. Malformations represent an error that occurred early in development. The event that caused the developmental error is temporally distant from the malformation we see in the fully developed animal. Knowledge of normal developmental principles is necessary to design thoughtful investigations that will define the events involved in abnormal development in wild frog populations.Development begins at the time an egg is fertilized and progresses by chemical communication between cells and cell layers. This communication is programmed through gene expression. Malformations represent primary errors in development, errors in chemical communication or translation of genetic information. Deformations arise later in development and usually result from the influence of mechanical factors (such as amputation) that alter shape or anatomy of a structure that has developed normally. The occurrence and the type of malformations are influenced by the type of error or insult as well as the timing of the error (the developmental stage at which the error occurred). The appearance of the malformation can therefore provide clues that suggest when the error may have occurred. If the malformation is an incomplete organ, such as an incomplete limb, the

  8. Outcrop sampling - methodology and its relation to coal bed methane reservoir potential. Field guide notes

    Energy Technology Data Exchange (ETDEWEB)

    Marchioni, D.; Strobl, R. (Petro-Logic Services (Canada))

    1990-01-01

    The regional geology for the Highvale Mine in the Wabamun coal field in Alberta is described with reference to the potential of Pit 2 for production of coal bed methane. An overview of the entire Ardley coal zone is given to show the lateral continuity of seams and rock partings on a deposit scale. Regional tectonics and geologic controls on coal development are described. Coal quality variations between seams and the role of coal quality on gas content and reservoir behaviour are discussed. Coal seam logging by the Australian system and sampling to produce a standard coal seam profile as a basis for correlation and sampling are discussed. A core view of the seam is compared to the outcrop view provided by the highwall. The reservoir characteristics of a coalbed methane well in this type of deposit is considered. Coal seam logging and sampling in an outcrop is described with regard to the seam profile, lithotypes and their composition, pillar and channel samples, weathering, and coal cleat or jointing. 19 refs, 13 figs., 1 tab.

  9. Virtual cathode microwave generation using inhomogeneous magnetic field and wave guide wall configuration

    International Nuclear Information System (INIS)

    Thode, L.E.; Kwan, T.J.T.

    1984-01-01

    Microwave generation from a virtual cathode system is investigated using two-dimensional particle-in-cell simulation. In the typical virtual cathode geometry, the electron beam diode is separated from the output waveguide by a ground plane which is a thin foil or screen. By lowering the diode impedance sufficiently, it is possible to form a virtual cathode in the waveguide region a short distance from the ground plane. In this configuration two mechanisms can lead to microwave generation: 1) electron bunching due to reflection between the real and virtual cathode and 2) electron bunching due to virtual cathode oscillation. Both mechanisms are typically present, but it appears possible to make one mechanism dominant by adjusting the output waveguide radius. Although such a configuration might generate 1-10 GW output, electron deposition into the ground plane, waveguide wall, and output window causes breakdown. To overcome these disadvantages, the authors have investigated a configuration with no ground plane coupled with the use of an inhomogeneous external magnetic field and waveguide wall

  10. Electromagnetic tracking for US-guided interventions: standardized assessment of a new compact field generator.

    Science.gov (United States)

    Franz, A M; März, K; Hummel, J; Birkfellner, W; Bendl, R; Delorme, S; Schlemmer, H-P; Meinzer, H-P; Maier-Hein, L

    2012-11-01

    One of the main challenges related to electromagnetic tracking in the clinical setting is a placement of the field generator (FG) that optimizes the reliability and accuracy of sensor localization. Recently, a new mobile FG for the NDI Aurora(®) tracking system has been presented. This Compact FG is the first FG that can be attached directly to an ultrasound (US) probe. The purpose of this study was to assess the precision and accuracy of the Compact FG in the presence of nearby mounted US probes. Six different US probes were mounted onto the Compact FG by means of a custom-designed mounting adapter. To assess precision and accuracy of the Compact FG, we employed a standardized assessment protocol. Utilizing a specifically manufactured plate, we measured positional data on three levels of distances from the FG as well as rotational data. While some probes had negligible influence on tracking accuracy two probes increased the mean distance error up to 1.5 mm compared with a reference measurement of 0.5 mm. The jitter error consistently stayed below 0.2 mm in all cases. The mean relative error in orientation was found to be smaller than 3°. Attachment of an US probe to the Compact FG does not have a critical influence on tracking accuracy in most cases. Clinical benefit of this promising mobile FG must be shown in future studies.

  11. 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

  12. 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.

  13. 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

  14. Hubble Space Telescope Deep Field Lesson Package. Teacher's Guide, Grades 6-8. Amazing Space: Education On-Line from the Hubble Space Telescope.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    This lesson guide accompanies the Hubble Deep Field set of 10 lithographs and introduces 4 astronomy lesson plans for middle school students. Lessons include: (1) "How Many Objects Are There?"; (2) "Classifying and Identifying"; (3) "Estimating Distances in Space"; and (4) "Review and Assessment." Appendices…

  15. Focusing electrode and coaxial reflector used for reducing the guiding magnetic field of the Ku-band foilless transit-time oscillator.

    Science.gov (United States)

    Ling, Junpu; Zhang, Jiande; He, Juntao; Wang, Lei; Deng, Bingfang

    2014-08-01

    Based on the theoretical analysis of the intense relativistic electron beam propagation in the coaxial drift-tube, a focusing electrode and a coaxial reflector is proposed to lessen the demand of the coaxial Ku-band foilless transit-time oscillator (TTO) for the guiding magnetic field. Moreover, a Ku-band TTO with the focusing electrode and the coaxial reflector is designed and studied by particle in cell simulation. When the diode voltage is 390 kV, the beam current 7.8 kA, and the guiding magnetic field is only 0.3 T, the device can output 820 MW microwave pulse at 14.25 GHz by means of the simulation. However, for the device without them, the output power is only 320 MW. The primary experiments are also carried out. When the guiding magnetic field is 0.3 T, the output power of the device with the focusing electrode and the coaxial reflector is double that of the one without them. The simulation and experimental results prove that the focusing electrode and the coaxial reflector are effective on reducing the guiding magnetic field of the device.

  16. Avian influenza : a review article

    Directory of Open Access Journals (Sweden)

    A. Yalda

    2006-07-01

    Full Text Available 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 the published literature about avian influenza. Since December 2003, highly pathogenic H5N1 avian influenza viruses have swept through poultry populations across Asia and parts of Europe. The outbreaks are historically unprecedented in scale and geographical spread. Their economic impact on the agricultural sector of the affected countries has been large. Human cases, with an overall fatality rate around 50%, have also been reported and almost all human infections can be linked to contact with infected poultry. Influenza viruses are genetically unstable and their behaviour cannot be predicted so the risk of further human cases persists. The human health implications have now gained importance, both for illness and fatalities that have occurred following natural infection with avian viruses, and for the potential of generating a re-assortant virus that could give rise to the next human influenza pandemic.

  17. 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.

  18. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2012-06-12

    ... Avian Influenza AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule... importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056...

  19. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Science.gov (United States)

    2011-05-03

    ... 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. The... vaccinated for certain types of avian influenza, or that have moved through regions where any subtype of...

  20. 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. © 2013 Published by Elsevier B.V.

  1. Field trip guide to selected studies of the Southwest Mineral and Environmental Investigations Project in southeastern Arizona

    Science.gov (United States)

    Houser, B.B.; Gettings, M.E.; Bultman, M.W.; Gray, Floyd; Caruthers, K.R.; Hirschberg, D.M.

    1999-01-01

    The Southwest Mineral and Environmental Investigations Project is designed to address issues raised by rapid urban development in the basins of the southwestern U.S. These issues require objective geoscientific data that can be used by land managers and stakeholders to develop informed land and water use strategies. The project integrates new and existing geologic, geophysical, and geochemical data, and imagery to provide three-dimensional visualizations of the basins of southeastern Arizona. Emphasis is on developing better knowledge of the aquifer systems of both the basins and the ranges, on acquiring background and baseline information, and on determining the distribution of metals related to mineralization and the fate of these metals in surface and subsurface environments. The products of the project will be used in resolving issues of water quality and quantity, in understanding environmental impacts such as riparian ecosystem maintenace, and in evaluating mineral resources beneath and within the basins. The field trip highlights three topics and areas (figs. 1 and 2): (1) geology and geophysics of the upper San Pedro and upper Santa Cruz basins (M.E. Gettings, M. W. Bultman, and B.B. Houser), (2) geology, geophysics, and mineral resource potential of the San Rafael basin (M.W. Bultman), and (3) hydrology and aqueous geochemistry of the Red Mountain and Sonoita Creek drainage system (Floyd Gray). The trip guide, which begins and ends in Tucson, Arizona, also includes commentary on the cultural and mining history of the area.

  2. TU-H-BRA-02: The Physics of Magnetic Field Isolation in a Novel Compact Linear Accelerator Based MRI-Guided Radiation Therapy System

    International Nuclear Information System (INIS)

    Low, D; Mutic, S; Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J

    2016-01-01

    Purpose: To develop a method for isolating the MRI magnetic field from field-sensitive linear accelerator components at distances close to isocenter. Methods: A MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. In order to accomplish this, the magnetron, port circulator, radiofrequency waveguide, gun driver, and linear accelerator needed to be placed in locations with low magnetic fields. The system was also required to be compact, so moving these components far from the main magnetic field and isocenter was not an option. The magnetic field sensitive components (exclusive of the waveguide) were placed in coaxial steel sleeves that were electrically and mechanically isolated and whose thickness and placement were optimized using E&M modeling software. Six sets of sleeves were placed 60° apart, 85 cm from isocenter. The Faraday effect occurs when the direction of propagation is parallel to the magnetic RF field component, rotating the RF polarization, subsequently diminishing RF power. The Faraday effect was avoided by orienting the waveguides such that the magnetic field RF component was parallel to the magnetic field. Results: The magnetic field within the shields was measured to be less than 40 Gauss, significantly below the amount needed for the magnetron and port circulator. Additional mu-metal was employed to reduce the magnetic field at the linear accelerator to less than 1 Gauss. The orientation of the RF waveguides allowed the RT transport with minimal loss and reflection. Conclusion: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of creating low magnetic field environments for the magnetic-field sensitive components, has been solved. The measured magnetic fields are sufficiently small to enable system integration. This work supported by ViewRay, Inc.

  3. 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

  4. So You Are Doing Research! An Annotated Guide to Library Materials in Political Science and Related Fields. Third Edition.

    Science.gov (United States)

    Davis, Ollye G., Comp.

    The third edition of an annotated guide to library materials is designed and intended for students majoring in political science; however, it would also be useful for instructors and students in the other social science disciplines. This handbook is divided into two sections: General Reference Books in the Social Sciences, and Guides and…

  5. Status of Avian Research at the National Renewable Energy Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, K.

    2001-09-18

    As the use of wind energy expands across the United States, concerns about the impacts of commercial wind farms on bird and bat populations are frequently raised. Two primary areas of concern are (1) possible litigation resulting from the killing of even one bird if it is protected by the Migratory Bird Treaty Act, the Endangered Species Act, or both; and (2) the effect of avian mortality on bird populations. To properly address these concerns, the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) supports scientifically based avian/wind power interaction research. In this paper I describe NREL's field-based research projects and summarize the status of the research. I also summarize NREL's other research activities, including lab-based vision research to increase the visibility of moving turbine blades and avian acoustic research, as well as our collaborative efforts with the National Wind Coordinating Committee's Avian Subcommittee.

  6. 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.

  7. 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...

  8. Control strategies against avian influenza

    Science.gov (United States)

    Since 1959, 40 epizootics of high pathogenicity avian influenza (HPAI) have occurred (Figure 1). Thirty-five of these epizootic HPAI viruses were geographically-limited (mostly to single countries), involved farm-to-farm spread and were eradicated from poultry by stamping-out programs; i.e. the HPAI...

  9. Avian metapneumovirus in the USA

    Science.gov (United States)

    In the United States of America (USA), avian metapneumovirus (aMPV) causes an upper respiratory tract infection in turkeys; no outbreaks have been reported in commercial chicken flocks. Typical clinical signs of the disease in turkey poults include coughing, sneezing, nasal discharge, tracheal rale...

  10. Reverse genetics of avian metapneumoviruses

    Science.gov (United States)

    An overview of avian metapneumovirus (aMPV) infection in turkeys and development of a reverse genetics system for aMPV subgroup C (aMPV-C) virus will be presented. By using reverse genetics technology, we generated recombinant aMPV-C viruses containing a different length of glycoprotein (G) gene or...

  11. On the Electrons Dynamics during Rapid Island Coalescence in Asymmetric Magnetic Reconnection: Case With and With No Guide Field

    Science.gov (United States)

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

    2015-12-01

    We present a set of fully kinetic 2.5D simulations of electron dynamics during rapid magnetic islands coalescence in asymmetric conditions. Simulations are performed using the massively parallel fully kinetic implicit moment method code iPIC3D (Markidis et al. 2010). The domain is a double periodic box with two current sheets initially representing two different reconnection conditions with the same asymmetric ratio. In the upper sheet the conventional hyperbolic continuous functions for magnetic field and density are initialised across the layer (e.g. Pritchett 2008). In the lower layer the same asymmetric conditions are used the presence of an extremely steep gradient describing a pure tangential discontinuity.Cases with and without guide field are compared. While the upper layer shows the typical reconnection evolution of an asymmetric configuration, the lower layer very soon develops not-uniformly distributed multiple reconnection points which rapidly evolve in a series of magnetic islands. Quick islands coalescence follows. Even though the electrons dynamics during island merging has been studied in both symmetric and asymmetric conditions (e.g. Pritchett 2007, 2008b, Drake et al. 2006, Oka et al. 2010, Huang et al. 2014), these simulations show new interesting features such as the presence of three distinct regions, here named X, M and D, with very different properties. Regions X and M manifest typical signatures of ongoing reconnection, distinguishable thanks to the direct comparison with the outcomes of the upper layer. In particular, M-type regions are different because reconnection occurs between two merging islands in a vertical fashion with respect to the direction of the current sheets initially set. In contrast, regions D present a quite diverse features, not showing the typical signatures of a occurring reconnection. The present work is supported by the NASA MMS Grant NNX08AO84G. Additional support for the KULeuven team is provided by the European

  12. Field-trip guide to Columbia River flood basalts, associated rhyolites, and diverse post-plume volcanism in eastern Oregon

    Science.gov (United States)

    Ferns, Mark L.; Streck, Martin J.; McClaughry, Jason D.

    2017-08-09

    The Miocene Columbia River Basalt Group (CRBG) is the youngest and best preserved continental flood basalt province on Earth, linked in space and time with a compositionally diverse succession of volcanic rocks that partially record the apparent emergence and passage of the Yellowstone plume head through eastern Oregon during the late Cenozoic. This compositionally diverse suite of volcanic rocks are considered part of the La Grande-Owyhee eruptive axis (LOEA), an approximately 300-kilometer-long (185 mile), north-northwest-trending, middle Miocene to Pliocene volcanic belt located along the eastern margin of the Columbia River flood basalt province. Volcanic rocks erupted from and preserved within the LOEA form an important regional stratigraphic link between the (1) flood basalt-dominated Columbia Plateau on the north, (2) bimodal basalt-rhyolite vent complexes of the Owyhee Plateau on the south, (3) bimodal basalt-rhyolite and time-transgressive rhyolitic volcanic fields of the Snake River Plain-Yellowstone Plateau, and (4) the High Lava Plains of central Oregon.This field-trip guide describes a 4-day geologic excursion that will explore the stratigraphic and geochemical relationships among mafic rocks of the Columbia River Basalt Group and coeval and compositionally diverse volcanic rocks associated with the early “Yellowstone track” and High Lava Plains in eastern Oregon. Beginning in Portland, the Day 1 log traverses the Columbia River gorge eastward to Baker City, focusing on prominent outcrops that reveal a distal succession of laterally extensive, large-volume tholeiitic flood lavas of the Grande Ronde, Wanapum, and Saddle Mountains Basalt formations of the CRBG. These “great flows” are typical of the well-studied flood basalt-dominated Columbia Plateau, where interbedded silicic and calc-alkaline lavas are conspicuously absent. The latter part of Day 1 will highlight exposures of middle to late Miocene silicic ash-flow tuffs, rhyolite domes, and

  13. MR-guided breast biopsy and hook wire marking using a low-field (0.23 T) scanner with optical instrument tracking

    International Nuclear Information System (INIS)

    Blanco Sequeiros, Roberto; Reinikainen, Heli; Blanco Sequeiros, Andreas M.; Ojala, Risto; Paeaekkoe, Eija; Tervonen, Osmo; Vaara, Teuvo

    2007-01-01

    The purpose of this study was to evaluate the technical feasibility of MR-guided percutaneous breast biopsy (LCNB) and breast hook wire marking in a low-field (0.23 T) MRI system with optical instrument tracking. MR-guided core biopsy and/or hook wire marking was performed on 13 lesions observable at MR imaging only. Seven breast LCNBs and 10 hook wire markings were performed under MR guidance on 11 patients. The diagnosis was confirmed by excision biopsy or mastectomy in 12 lesions and with histopathological and cytological diagnosis and 12-month clinical follow-up in one lesion. All lesions seen in the high-field scanner were also successfully identified and targeted in the low-field scanner. The following procedures were typically technically successful. There were difficulties due to unsatisfactory functioning of some core biopsy guns. Detailed description of low-field MR guidance and optical tracking in breast biopsies is provided. The procedure seems accurate and safe and provides means to obtain a histological diagnosis of a breast lesion only seen with MRI. The low-field biopsy system is comparable to the high-field MRI system. MR-compatible biopsy guns need to be improved. (orig.)

  14. Understanding of and possible strategies to avian influenza outbreak.

    Science.gov (United States)

    Shen, Junkang; Zhang, Andy; Xu, Huifen; Sirois, Pierre; Zhang, Jia; Li, Kai; Xiao, Li

    2013-01-01

    Swine flu and avian flu outbreaks have occurred in recent years in addition to seasonal flu. As mortality rate records are not available at the early stage of an outbreak, two parameters may be useful to assess the viral virulence : 1. the time required for the first domestic case in a newly involved region, and 2. the doubling time of new infected cases. Viral virulence is one of the most important factors in guiding short term and immediate responses. Although routine surveillance and repeated vaccination are useful efforts, some novel strategies that may be relevant to prevent and control the spread of influenza among human beings and domestic animals are discussed.

  15. The avian egg exhibits general allometric invariances in mechanical design.

    Science.gov (United States)

    Juang, Jia-Yang; Chen, Pin-Yi; Yang, Da-Chang; Wu, Shang-Ping; Yen, An; Hsieh, Hsin-I

    2017-10-27

    The avian egg exhibits extraordinary diversity in size, shape and color, and has a key role in avian adaptive radiations. Despite extensive work, our understanding of the underlying principles that guide the "design" of the egg as a load-bearing structure remains incomplete, especially over broad taxonomic scales. Here we define a dimensionless number C, a function of egg weight, stiffness and dimensions, to quantify how stiff an egg is with respect to its weight after removing geometry-induced rigidity. We analyze eggs of 463 bird species in 36 orders across five orders of magnitude in body mass, and find that C number is nearly invariant for most species, including tiny hummingbirds and giant elephant birds. This invariance or "design guideline" dictates that evolutionary changes in shell thickness and Young's modulus, both contributing to shell stiffness, are constrained by changes in egg weight. Our analysis illuminates unique reproductive strategies of brood parasites, kiwis, and megapodes, and quantifies the loss of safety margin for contact incubation due to artificial selection and environmental toxins. Our approach provides a mechanistic framework for a better understanding of the mechanical design of the avian egg, and may provide clues to the evolutionary origin of contact incubation of amniote eggs.

  16. Plamonics for Biomolecular Sensors and THz Metamaterial Waveguides (Near and Far-Field Interfaces to DNA. Guided Nanostructures from RF to Lightwave: Exploiting the Spectrum)

    Science.gov (United States)

    2014-12-17

    Spectrum for MURI- UCI 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: In THz frequencies, the textured surfaces on a subwavelength scale can support...Near and Far-Field Interfaces to DNA.Guided Nanostructures from RF to Lightwave: Exploiting the Spectrum for MURI- UCI Report Title In THz...interferometer and, more particularly, a Mach-Zehnder Interferometer having a doubly-corrugated spoofed surface plasmon polariton waveguide. ARO & MURI ( UCI

  17. 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.

  18. Discontinuous finite element space-angle treatment of the first order linear Boltzmann transport equation with magnetic fields: Application to MRI-guided radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    St Aubin, J., E-mail: joel.st.aubin@albertahealthservices.ca [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2, Canada and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Keyvanloo, A. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, Edmonton, Alberta T6G 2M9 (Canada)

    2016-01-15

    Purpose: The advent of magnetic resonance imaging (MRI) guided radiotherapy systems demands the incorporation of the magnetic field into dose calculation algorithms of treatment planning systems. This is due to the fact that the Lorentz force of the magnetic field perturbs the path of the relativistic electrons, hence altering the dose deposited by them. Building on the previous work, the authors have developed a discontinuous finite element space-angle treatment of the linear Boltzmann transport equation to accurately account for the effects of magnetic fields on radiotherapy doses. Methods: The authors present a detailed description of their new formalism and compare its accuracy to GEANT4 Monte Carlo calculations for magnetic fields parallel and perpendicular to the radiation beam at field strengths of 0.5 and 3 T for an inhomogeneous 3D slab geometry phantom comprising water, bone, and air or lung. The accuracy of the authors’ new formalism was determined using a gamma analysis with a 2%/2 mm criterion. Results: Greater than 98.9% of all points analyzed passed the 2%/2 mm gamma criterion for the field strengths and orientations tested. The authors have benchmarked their new formalism against Monte Carlo in a challenging radiation transport problem with a high density material (bone) directly adjacent to a very low density material (dry air at STP) where the effects of the magnetic field dominate collisions. Conclusions: A discontinuous finite element space-angle approach has been proven to be an accurate method for solving the linear Boltzmann transport equation with magnetic fields for cases relevant to MRI guided radiotherapy. The authors have validated the accuracy of this novel technique against GEANT4, even in cases of strong magnetic field strengths and low density air.

  19. An Applied-Scientific Approach to Field Assessments - Try It Out - A Field Guide for Practitioners (Une approche scientifique des evaluations de terrain - Essayer le - Un guide de terrain a destination des praticiens)

    Science.gov (United States)

    2017-12-01

    Planning 11 2.3.1 Q3-1: What do I need to look for? 12 2.3.2 Q3-2: In which specific setting are you going to collect the data? 12 2.3.3 Q3-3: What data...than going for high level scientific rigor this guide aims to provide a practical method to improve assessment efforts that might be based on simple...problem owner and decision maker concerning direction and extends of the assessment. The Guide is based on scientific and operational experiences and

  20. Avian binocular vision: It's not just about what birds can see, it's also about what they can't.

    Directory of Open Access Journals (Sweden)

    Luke P Tyrrell

    Full Text Available With the exception of primates, most vertebrates have laterally placed eyes. Binocular vision in vertebrates has been implicated in several functions, including depth perception, contrast discrimination, etc. However, the blind area in front of the head that is proximal to the binocular visual field is often neglected. This anterior blind area is important when discussing the evolution of binocular vision because its relative length is inversely correlated with the width of the binocular field. Therefore, species with wider binocular fields also have shorter anterior blind areas and objects along the mid-sagittal plane can be imaged at closer distances. Additionally, the anterior blind area is of functional significance for birds because the beak falls within this blind area. We tested for the first time some specific predictions about the functional role of the anterior blind area in birds controlling for phylogenetic effects. We used published data on visual field configuration in 40 species of birds and measured beak and skull parameters from museum specimens. We found that birds with proportionally longer beaks have longer anterior blind areas and thus narrower binocular fields. This result suggests that the anterior blind area and beak visibility do play a role in shaping binocular fields, and that binocular field width is not solely determined by the need for stereoscopic vision. In visually guided foragers, the ability to see the beak-and how much of the beak can be seen-varies predictably with foraging habits. For example, fish- and insect-eating specialists can see more of their own beak than birds eating immobile food can. But in non-visually guided foragers, there is no consistent relationship between the beak and anterior blind area. We discuss different strategies-wide binocular fields, large eye movements, and long beaks-that minimize the potential negative effects of the anterior blind area. Overall, we argue that there is more to

  1. Evidence-Based Advances in Avian Medicine.

    Science.gov (United States)

    Summa, Noémie M; Guzman, David Sanchez-Migallon

    2017-09-01

    This article presents relevant advances in avian medicine and surgery over the past 5 years. New information has been published to improve clinical diagnosis in avian diseases. This article also describes new pharmacokinetic studies. Advances in the understanding and treatment of common avian disorders are presented in this article, as well. Although important progress has been made over the past years, there is still much research that needs to be done regarding the etiology, pathophysiology, diagnosis, and treatment of avian diseases and evidence-based information is still sparse in the literature. Copyright © 2017 Elsevier Inc. All rights reserved.

  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. 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.

  4. Gender determination of avian embryo

    Energy Technology Data Exchange (ETDEWEB)

    Daum, Keith A. (Idaho Falls, ID); Atkinson, David A. (Idaho Falls, ID)

    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. MMS Observations of Large Guide Field Symmetric Reconnection Between Colliding Reconnection Jets at the Center of a Magnetic Flux Rope at the Magnetopause

    Science.gov (United States)

    Oieroset, M.; Phan, T. D.; Haggerty, C.; Shay, M. A.; Eastwood, J. P.; Gershman, D. J.; Drake, J. F.; Fujimoto, M.; Ergun, R. E.; Mozer, F. S.; hide

    2016-01-01

    We report evidence for reconnection between colliding reconnection jets in a compressed current sheet at the center of a magnetic flux rope at Earth's magnetopause. The reconnection involved nearly symmetric Inflow boundary conditions with a strong guide field of two. The thin (2.5 ion-skin depth (d(sub i) width) current sheet (at approximately 12 d(sub i) downstream of the X line) was well resolved by MMS, which revealed large asymmetries in plasma and field structures in the exhaust. Ion perpendicular heating, electron parallel heating, and density compression occurred on one side of the exhaust, while ion parallel heating and density depression were shifted to the other side. The normal electric field and double out-of-plane (bifurcated) currents spanned almost the entire exhaust. These observations are in good agreement with a kinetic simulation for similar boundary conditions, demonstrating in new detail that the structure of large guide field symmetric reconnection is distinctly different from antiparallel reconnection.

  6. MiDAS Field Guide – a Comprehensive Online Source of Information About the Microbes of Activated Sludge

    DEFF Research Database (Denmark)

    Nierychlo, Marta; McIlroy, Simon Jon; Saunders, Aaron Marc

    activated sludge wastewater treatment systems, linking their identity with available information on their function and distribution. The guide includes the approx. 100 abundant genera that are present in most treatment plants (based on a survey of 25 full-scale Danish wastewater treatment plants ...

  7. Killing Fields: The Deadly Legacy of Landmines. Study Guide. Episode #738. America's Defense Monitor, Educational TV for the Classroom.

    Science.gov (United States)

    Center for Defense Information, Washington, DC.

    This program explores the dangers of landmines as "weapons of mass destruction in slow motion." These hidden killers have been called the "perfect soldier"--never sleeping and never missing--yet kill thousands of people each year, many innocent civilians. The study guide offers questions to use before viewing the video,…

  8. Pathogenesis of avian pneumovirus infection in turkeys.

    Science.gov (United States)

    Jirjis, F F; Noll, S L; Halvorson, D A; Nagaraja, K V; Shaw, D P

    2002-05-01

    Avian pneumovirus (APV) is the cause of a respiratory disease of turkeys characterized by coughing, ocular and nasal discharge, and swelling of the infraorbital sinuses. Sixty turkey poults were reared in isolation conditions. At 3 weeks of age, serum samples were collected and determined to be free of antibodies against APV, avian influenza, hemorrhagic enteritis, Newcastle disease, Mycoplasma gallisepticum, Mycoplasma synoviae, Mycoplasma meleagridis, Ornithobacterium rhinotracheale, and Bordetella avium. When the poults were 4 weeks old, they were inoculated with cell culture-propagated APV (APV/Minnesota/turkey/2a/97) via the conjunctival spaces and nostrils. After inoculation, four poults were euthanatized every 2 days for 14 days, and blood, swabs, and tissues were collected. Clinical signs consisting of nasal discharge, swelling of the infraorbital sinuses, and frothy ocular discharge were evident by 2 days postinoculation (PI) and persisted until day 12 PI. Mild inflammation of the mucosa of the nasal turbinates and infraorbital sinuses was present between days 2 and 10 PI. Mild inflammatory changes were seen in tracheas of poults euthanatized between days 4 and 10 PI. Antibody to APV was detected by day 7 PI. The virus was detected in tissue preparations and swabs of nasal turbinates and infraorbital sinuses by reverse transcription polymerase chain reaction, virus isolation, and immunohistochemical staining methods between days 2 and 10 PI. Virus was detected in tracheal tissue and swabs between days 2 and 6 PI using the same methods. In this experiment, turkey poults inoculated with tissue culture-propagated APV developed clinical signs similar to those seen in field cases associated with infection with this virus.

  9. 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.

  10. Simulation and measurement of log-periodic antenna and double ridged guide horn antenna for optimized field uniformity

    NARCIS (Netherlands)

    Mandaris, Dwi; Leferink, Frank

    2017-01-01

    Three basic types of antennas have been designed and simulated for field calibration, i.e. field homogeneity or uniformity, and power efficiency. The objective is to develop the best antenna in terms of field uniformity and power efficiency. Experiments have been performed according to IEC 61000-4-3

  11. Seasonality, distribution and taxonomic status of avian ...

    African Journals Online (AJOL)

    Description of a new species is based upon morphology of gametocyte development in the peripheral blood of the avian host. This does not distinguish between morphologically identical gametocytes from different avian host families, nor is species or family level a valid taxonomic character. Thus, Haemoproteus and ...

  12. 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...

  13. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  14. Avian Influenza Policy Analysis | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Governments in Southeast Asia have adopted a range of policies aimed at controlling the disease in animals, preventing its spread to humans and strengthening national preparedness for an avian influenza pandemic. The Asia Partnership for Avian Influenza Research (APAIR) brings together national research agencies ...

  15. MANAGING AVIAN FLU, CARCASS MANAGEMENT & BIOSOLIDS

    Science.gov (United States)

    The avian influenza virus is discussed with emphasis on the impact to poultry and possible movement of the highly pathogenic H5N 1 virus to humans. A review is made of the worldwide effects to date of the avian influenza viruses; methods for the viruses to enter recreational wate...

  16. Flora and Field Guide References Supporting All U.S. Army Corps of Engineers Wetland Regional Supplements

    Science.gov (United States)

    2011-11-01

    list is divided into the following categories: forbs, shrubs, trees, grasses and sedges, ferns, orchids, cacti and agave , and references and help...this list are broken down into groups: forbs, shrubs, trees, grasses and sedges, ferns, orchids, cacti and agave , and ref- erences and help guides. The... Agave Benson, L. 1982. The Cacti of the United States and Canada. Chicago, IL: Stanford University Press. Gentry, H. S. 1982. Agaves of the

  17. 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.

  18. Avian assemblages in the lower Missouri river floodplain

    Science.gov (United States)

    Thogmartin, W.E.; Gallagher, M.; Young, N.; Rohweder, J.J.; Durbian, F.; Knutson, M.G.

    2009-01-01

    Floodplain habitat provides important migration and breeding habitat for birds in the midwestern United States. However, few studies have examined how the avian assemblage changes with different stages of floodplain forest succession in the midwestern United States. In spring and summer from 2002 to 2004, we conducted 839 point counts in wet prairie/forbs fields, 547 point counts in early successional forests, and 434 point counts in mature forests to describe the migrating and breeding bird assemblage in the lower Missouri River floodplain. We recorded 131, 121, and 141 species in the three respective habitats, a number higher than most locations in the midwestern United States and comprising > 15% of all avian species in North America. Avian species diversity generally increased from west to east along the river, differed among land cover classes, but overlapped between seasons (migration and breeding) and years. Wet prairies were particularly important for conservation as there were 20 species of high conservation concern observed, including Dickcissels (Spiza americana). Important species for monitoring biotic integrity included the Northern Harrier (Circus cyaneus) and Bobolink (Dolichonyx oryzivorus) in wet prairie, Bell's Vireo (Vireo bellii) in early successional forest, and Northern Parula (Parula americana) and Prothonotary Warbler (Protonotaria citrea) in mature forest. ?? 2009, The Society of Wetland Scientists.

  19. 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.

  20. 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.

  1. Field-trip guide to the vents, dikes, stratigraphy, and structure of the Columbia River Basalt Group, eastern Oregon and southeastern Washington

    Science.gov (United States)

    Camp, Victor E; Reidel, Stephen P.; Ross, Martin E.; Brown, Richard J.; Self, Stephen

    2017-06-22

    The Columbia River Basalt Group covers an area of more than 210,000 km2 with an estimated volume of 210,000 km3. As the youngest continental flood-basalt province on Earth (16.7–5.5 Ma), it is well preserved, with a coherent and detailed stratigraphy exposed in the deep canyonlands of eastern Oregon and southeastern Washington. The Columbia River flood-basalt province is often cited as a model for the study of similar provinces worldwide.This field-trip guide explores the main source region of the Columbia River Basalt Group and is written for trip participants attending the 2017 International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Scientific Assembly in Portland, Oregon, USA. The first part of the guide provides an overview of the geologic features common in the Columbia River flood-basalt province and the stratigraphic terminology used in the Columbia River Basalt Group. The accompanying road log examines the stratigraphic evolution, eruption history, and structure of the province through a field examination of the lavas, dikes, and pyroclastic rocks of the Columbia River Basalt Group.

  2. Test of Shi et al. Method to Infer the Magnetic Reconnection Geometry from Spacecraft Data: MHD Simulation with Guide Field and Antiparallel Kinetic Simulation

    Science.gov (United States)

    Denton, R.; Sonnerup, B. U. O.; Swisdak, M.; Birn, J.; Drake, J. F.; Heese, M.

    2012-01-01

    When analyzing data from an array of spacecraft (such as Cluster or MMS) crossing a site of magnetic reconnection, it is desirable to be able to accurately determine the orientation of the reconnection site. If the reconnection is quasi-two dimensional, there are three key directions, the direction of maximum inhomogeneity (the direction across the reconnection site), the direction of the reconnecting component of the magnetic field, and the direction of rough invariance (the "out of plane" direction). Using simulated spacecraft observations of magnetic reconnection in the geomagnetic tail, we extend our previous tests of the direction-finding method developed by Shi et al. (2005) and the method to determine the structure velocity relative to the spacecraft Vstr. These methods require data from four proximate spacecraft. We add artificial noise and calibration errors to the simulation fields, and then use the perturbed gradient of the magnetic field B and perturbed time derivative dB/dt, as described by Denton et al. (2010). Three new simulations are examined: a weakly three-dimensional, i.e., quasi-two-dimensional, MHD simulation without a guide field, a quasi-two-dimensional MHD simulation with a guide field, and a two-dimensional full dynamics kinetic simulation with inherent noise so that the apparent minimum gradient was not exactly zero, even without added artificial errors. We also examined variations of the spacecraft trajectory for the kinetic simulation. The accuracy of the directions found varied depending on the simulation and spacecraft trajectory, but all the directions could be found within about 10 for all cases. Various aspects of the method were examined, including how to choose averaging intervals and the best intervals for determining the directions and velocity. For the kinetic simulation, we also investigated in detail how the errors in the inferred gradient directions from the unmodified Shi et al. method (using the unperturbed gradient

  3. Safety of High Speed Guided Ground Transportation Systems. Broadband Magnetic Fields : Their Possible Role in EMF Associated Bioeffects

    Science.gov (United States)

    1993-08-01

    This report reviews electric and magnetic field (EMF) exposures from electrical transportation systems, including : electrically powered rail and magnetic levitation (maglev). Material also covered includes research concerning : biological effects of...

  4. A one-and-a-quarter-dimensional transport code for field-reversed configuration studies: A user's guide for CFRX

    International Nuclear Information System (INIS)

    Hsiao, Ming-Yuan; Werley, K.A.; Ling, Kuok-Mee.

    1988-05-01

    A one-and-a-quarter-dimensional transport code, which includes radial as well as some two-dimensional effects for field-reversed configurations, is described. The set of transport equations is transformed to a set of new independent and dependent variables and is solved as a coupled initial-boundary value problem. The code simulation includes both the closed and open field regions. The axial effects incorporated include global axial force balance, axial losses in the open field region, and flux surface averaging over the closed field region. Input, output, and structure of the code are described in detail. A typical example of the code results is also given. 20 refs., 21 figs., 7 tabs

  5. Investigation of the 4D composite MR image distortion field associated with tumor motion for MR-guided radiotherapy.

    Science.gov (United States)

    Stanescu, T; Jaffray, D

    2016-03-01

    Magnetic resonance (MR) images are affected by geometric distortions due to the specifics of the MR scanner and patient anatomy. Quantifying the distortions associated with mobile tumors is particularly challenging due to real anatomical changes in the tumor's volume, shape, and relative location within the MR imaging volume. In this study, the authors investigate the 4D composite distortion field, which combines the effects of the susceptibility-induced and system-related distortion fields, experienced by mobile lung tumors. The susceptibility (χ) effects were numerically simulated for two specific scenarios: (a) a full motion cycle of a lung tumor due to breathing as depicted on ten phases of a 4D CBCT data set and (b) varying the tumor size and location in lung tissue via a synthetically generated sphere with variable diameter (4-80 mm). The χ simulation procedure relied on the segmentation and generation of 3D susceptibility (χ) masks and computation of the magnetic field by means of finite difference methods. A system-related distortion field, determined with a phantom and image processing algorithm, was used as a reference. The 4D composite distortion field was generated as the vector summation of the χ-induced and system-related fields. The analysis was performed for two orientations of the main magnetic field (B0), which correspond to several MRIgRT system configurations. Specifically, B0 was set along the z-axis as in the case of a cylindrical-bore scanner and in the (x,y)-plane as for a biplanar MR. Computations were also performed for a full revolution at 15° increments in the case of a rotating biplanar magnet. Histograms and metrics such as maximum, mean, and range were used to evaluate the characteristics of the 4D distortion field. The χ-induced field depends on the change in volume and shape of the moving tumor as well as the local surrounding anatomy. In the case of system-related distortions, the tumor experiences increased field

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

    OpenAIRE

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

    2012-01-01

    Please cite this paper as: Hall et al. (2012) Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00358.x. 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 l...

  7. Muscle co-contraction patterns in robot-mediated force field learning to guide specific muscle group training.

    Science.gov (United States)

    Pizzamiglio, Sara; Desowska, Adela; Shojaii, Pegah; Taga, Myriam; Turner, Duncan L

    2017-01-01

    Muscle co-contraction is a strategy of increasing movement accuracy and stability employed in dealing with force perturbation of movement. It is often seen in neuropathological populations. The direction of movement influences the pattern of co-contraction, but not all movements are easily achievable for populations with motor deficits. Manipulating the direction of the force instead, may be a promising rehabilitation protocol to train movement with use of a co-contraction reduction strategy. Force field learning paradigms provide a well described procedure to evoke and test muscle co-contraction. The aim of this study was to test the muscle co-contraction pattern in a wide range of arm muscles in different force-field directions utilising a robot-mediated force field learning paradigm of motor adaptation. Forty-two participants volunteered to participate in a study utilising robot-mediated force field motor adaptation paradigm with a clockwise or counter-clockwise force field. Kinematics and surface electromyography (EMG) of eight arm muscles were measured. Both muscle activation and co-contraction was earlier and stronger in flexors in the clockwise condition and in extensors in the counter-clockwise condition. Manipulating the force field direction leads to changes in the pattern of muscle co-contraction.

  8. 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.

  9. 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, Joshua T.; 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.

  10. 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.

  11. Student-guided field based investigations of microplastic contamination in urban waterways as a tool to introduce environmental science students to scientific inquiry

    Science.gov (United States)

    Pondell, C.

    2016-12-01

    Microplastic pollution is becoming an increasing concern in oceanographic and environmental studies, and offers an opportunity to engage undergraduate students in environmental research using a highly relevant field of investigation. For instance, a majority of environmental science majors not only know about the Great Pacific Garbage Patch, but can also list off several statistics about its size and impact on marine life. Building on this enthusiasm for understanding the impact of microplastics on the environment, a laboratory class was designed to introduce environmental science majors to the rigors of scientific investigation using microplastic pollution in urban waterways as the focus of their laboratory experience. Over a seven-week period, students worked in small groups to design an experiment, collect samples in the field, analyze the samples in the lab, and present their findings in a university-wide forum. Their research questions focused on developing a better understanding of the transportation and fate of microplastics in the urban waterways of Washington, D.C. This presentation will explore the benefits and challenges associated with a student guided field study for environmental science undergraduates, and will describe results and student feedback from their urban microplastic field study.

  12. Species diversity of dry season avian fauna in Kano, Nigeria | Ishaq ...

    African Journals Online (AJOL)

    The avian fauna in Nigeria and the rest of West Africa is fairly rich, especially during the rainy season when most of the birds are breeding. However, the frequency of species encounter in the field changes as the dry season progresses. The present study examined the diversity of birds during the three dry months following ...

  13. Recombinant viral-vectored vaccines for the control of avian influenza in poultry

    Science.gov (United States)

    Vaccination is a commonly used tool for the control of both low pathogenic and highly pathogenic avian influenza viruses. Traditionally inactivated adjuvanted vaccines made from a low pathogenic field strain has been used for vaccination, but advances in molecular biology has allowed a number of di...

  14. Maternal hormones as a tool to adjust offspring phenotype in avian species

    NARCIS (Netherlands)

    Groothuis, TGG; Muller, W; von Engelhardt, N; Carere, C; Eising, C; Groothuis, Ton G.G.

    Avian eggs contain substantial amounts of maternal hormones and so provide an excellent model to study hormone-mediated maternal effects. We review this new and rapidly evolving field, taking an ecological and evolutionary approach and focusing on effects and function of maternal androgens in

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

    Data.gov (United States)

    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...

  16. 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.

  17. Synthesis of regional wildlife and vegetation field studies to guide management of standing and down dead trees

    Science.gov (United States)

    Bruce G. Marcot; Janet L. Ohmann; Kim L. Mellen-McLean; Karen L. Waddell

    2010-01-01

    We used novel methods for combining information from wildlife and vegetation field studies to develop guidelines for managing dead wood for wildlife and biodiversity. The DecAID Decayed Wood Adviser presents data on wildlife use of standing and down dead trees (snags and down wood) and summaries of regional vegetation plot data depicting dead wood conditions, for...

  18. How to Use Value-Added Analysis to Improve Student Learning: A Field Guide for School and District Leaders

    Science.gov (United States)

    Kennedy, Kate; Peters, Mary; Thomas, Mike

    2012-01-01

    Value-added analysis is the most robust, statistically significant method available for helping educators quantify student progress over time. This powerful tool also reveals tangible strategies for improving instruction. Built around the work of Battelle for Kids, this book provides a field-tested continuous improvement model for using…

  19. A Consumer's Guide to Personnel Preparation Programs: The Training of Paraprofessionals in Special Education and Related Fields.

    Science.gov (United States)

    New Mexico Univ., Albuquerque.

    Described are 77 programs that have evolved to train teaching assistants, youth service aides, counselors, recreation aides, physical therapy assistants, child care workers, group home supervisors, interpreters, and other types of paraprofessionals for special education and related fields. Provided in an initial section is a brief analysis of…

  20. Avian endocrine responses to environmental pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Rattner, B.A.; Eroschenko, V.P.; Fox, G.A.; Fry, D.M.; Gorsline, J.

    1984-12-01

    Many environmental contaminants are hazardous to populations of wild birds. Chlorinated hydrocarbon pesticides and industrial pollutants are thought to be responsible for population declines of several species of predatory birds through eggshell thinning. Studies have demonstrated that these contaminants have estrogenic potency and may affect the functioning of the gonadal and thyroidal endocrine subsystems. Petroleum crude oil exerts toxicity externally, by oiling of plumage, and internally, by way of ingestion of oil while feeding or preening. Extensive ultrastructural damage to the inner zone of the adrenal, diminished adrenal responsiveness to adrenocorticotrophic hormone, and reduced corticosterone secretion rate suggest that low levels of plasma corticosterone reflect a direct effect of petroleum on the adrenal gland. Suppressive effects of oil on the ovary and decreases in circulating prolactin have been associated with impaired reproductive function. Large-scale field studies of free-living seabirds have confirmed some of the inhibitory effects of oil on reproduction that have been observed in laboratory studies. Organophosphorus insecticides, representing the most widely used class of pesticides in North America, have been shown to impair reproductive function, possibly by altering secretion of luteinizing hormone and progesterone. Relevant areas of future research on the effects of contaminants on avian endocrine function are discussed.

  1. Isolation of avian influenza virus in Texas.

    Science.gov (United States)

    Glass, S E; Naqi, S A; Grumbles, L C

    1981-01-01

    An avian influenza virus with surface antigens similar to those of fowl plague virus (Hav 1 Nav 2) was isolated in 1979 from 2 commercial turkey flocks in Central Texas. Two flocks in contact with these infected flocks developed clinical signs, gross lesions, and seroconversion but yielded no virus. This was the first recorded incidence of clinical avian influenza in Texas turkeys and only the second time that an agent with these surface antigens was isolated from turkeys in U.S.

  2. A Synthesis of Human-related Avian Mortality in Canada

    Directory of Open Access Journals (Sweden)

    Anna M. Calvert

    2013-12-01

    involved, potential for population-level effects, and the cumulative effects of mortality across the landscape. Effort is still required to improve these estimates, and to guide conservation efforts to minimize direct mortality caused by human activities on Canada's wild bird populations. As avian mortality represents only a portion of the overall impact to avifauna, indirect effects such as habitat fragmentation and alteration, site avoidance, disturbance, and related issues must also be carefully considered.

  3. Diversity of Multi-Drug Resistant Avian Pathogenic Escherichia coli (APEC) Causing Outbreaks of Colibacillosis in Broilers during 2012 in Spain

    OpenAIRE

    Sol?-Gin?s, Marc; Cameron-Veas, Karla; Badiola, Ignacio; Dolz, Roser; Maj?, Natalia; Dahbi, Ghizlane; Viso, Susana; Mora, Azucena; Blanco, Jorge; Piedra-Carrasco, Nuria; Gonz?lez-L?pez, Juan Jos?; Migura-Garcia, Lourdes

    2015-01-01

    Avian pathogenic Escherichia coli (APEC) are the major cause of colibacillosis in poultry production. In this study, a total of 22 E. coli isolated from colibacillosis field cases and 10 avian faecal E. coli (AFEC) were analysed. All strains were characterised phenotypically by susceptibility testing and molecular typing methods such as pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). The presence of 29 virulence genes associated to APEC and human extraintestina...

  4. 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.

  5. The North Sea field development guide. V.1: Northern North Sea. V.2: Southern North Sea. 6. ed.

    International Nuclear Information System (INIS)

    Anon.

    1996-08-01

    The 1997/8, sixth edition is the first to be divided into two volumes. Volume 1 covers the central and northern North Sea areas; volume 2 contains the southern North Sea as well as the Irish and German sectors. The pages are numbered consecutively over the two volumes, with page numbers greater than 702 contained in the second volume. There are three index sections. Main index. Arranged by national sector (UK, Norway etc.) Within each sector the entries are alphabetical by operator name. This index contains page numbers for the book entries: the other two index sections should be used with the main index to find the exact location of an entry; Index by field. If the reader knows a field name (e.g. Kittiwake) but not the operator or the national sector, this index will reference them; Index by installation. Each installation (''Fulmar SALM'', ''Togi'') is named, giving the operator, field and national sector where it is located. This index is also useful for locating particular kinds of installations, such as subsea completions; The book is intended to provide a factual overview of field development activity in the North Sea (a term loosely used to include the Irish Sea and the Baltic Sea). The aim is therefore to provide some background, specifications and history on every offshore installation in that area. Speculative or evaluative commentary is avoided where possible. No attempt has been made to forecast the form or probability of future developments, except in those few instances where announcements have been made by the oil company itself, and these are, clearly indicated. (UK)

  6. 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.

  7. Arsenic associated with historical gold mining in the Sierra Nevada foothills: Case study and field trip guide for Empire Mine State Historic Park, California

    Science.gov (United States)

    Alpers, Charles N.; Myers, Perry A; Millsap, Daniel; Regnier, Tamsen B; Bowell, Robert J.; Alpers, Charles N.; Jamieson, Heather E.; Nordstrom, D. Kirk; Majzlan, Juraj

    2014-01-01

    The Empire Mine, together with other mines in the Grass Valley mining district, produced at least 21.3 million troy ounces (663 tonnes) of gold (Au) during the 1850s through the 1950s, making it the most productive hardrock Au mining district in California history (Clark 1970). The Empire Mine State Historic Park (Empire Mine SHP or EMSHP), established in 1975, provides the public with an opportunity to see many well-preserved features of the historic mining and mineral processing operations (CDPR 2014a).A legacy of Au mining at Empire Mine and elsewhere is contamination of mine wastes and associated soils, surface waters, and groundwaters with arsenic (As), mercury (Hg), lead (Pb), and other metals. At EMSHP, As has been the principal contaminant of concern and the focus of extensive remediation efforts over the past several years by the State of California, Department of Parks and Recreation (DPR) and Newmont USA, Ltd. In addition, the site is the main focus of a multidisciplinary research project on As bioavailability and bioaccessibility led by the California Department of Toxic Substances Control (DTSC) and funded by the U.S. Environmental Protection Agency’s (USEPA’s) Brownfields Program.This chapter was prepared as a guide for a field trip to EMSHP held on June 14, 2014, in conjunction with a short course on “Environmental Geochemistry, Mineralogy, and Microbiology of Arsenic” held in Nevada City, California on June 15–16, 2014. This guide contains background information on geological setting, mining history, and environmental history at EMSHP and other historical Au mining districts in the Sierra Nevada, followed by descriptions of the field trip stops.

  8. Avian Species and Functional Diversity in Agricultural Landscapes: Does Landscape Heterogeneity Matter?

    Science.gov (United States)

    Lee, Myung-Bok; Martin, James A

    2017-01-01

    While the positive relationship between avian diversity and habitat heterogeneity is widely accepted, it is primarily based on observed species richness without accounting for imperfect detection. Other facets of diversity such as functional diversity are also rarely explored. We investigated the avian diversity-landscape heterogeneity relationship in agricultural landscapes by considering two aspects of diversity: taxonomic diversity (species richness) estimated from a multi-species dynamic occupancy model, and functional diversity (functional evenness [FEve] and divergence [FDiv]) based on traits of occurring species. We also assessed how agricultural lands enrolled in a conservation program managed on behalf of declining early successional bird species (hereafter CP38 fields, an agri-environment scheme) influenced avian diversity. We analyzed breeding bird data collected at CP38 fields in Mississippi, USA, during 2010-2012, and two principal components of environmental variables: a gradient of heterogeneity (Shannon's landscape diversity index) and of the amount of CP38 fields (percent cover of CP38 fields; CP38). FEve did not show significant responses to environmental variables, whereas FDiv responded positively to heterogeneity and negatively to CP38. However, most FDiv values did not significantly differ from random expectations along an environmental gradient. When there was a significant difference, FDiv was lower than that expected. Unlike functional diversity, species richness showed a clear pattern. Species richness increased with increasing landscape heterogeneity but decreased with increasing amounts of CP38 fields. Only one species responded negatively to heterogeneity and positively to CP38. Our results suggest that the relationships between avian diversity and landscape heterogeneity may vary depending on the aspect of diversity considered: strong positive effects of heterogeneity on taxonomic diversity, but weakly positive or non

  9. Mosquito age and avian malaria infection.

    Science.gov (United States)

    Pigeault, Romain; Nicot, Antoine; Gandon, Sylvain; Rivero, Ana

    2015-09-30

    The immune system of many insects wanes dramatically with age, leading to the general prediction that older insects should be more susceptible to infection than their younger counterparts. This prediction is however challenged by numerous studies showing that older insects are more resistant to a range of pathogens. The effect of age on susceptibility to infections is particularly relevant for mosquitoes given their role as vectors of malaria and other diseases. Despite this, the effect of mosquito age on Plasmodium susceptibility has been rarely explored, either experimentally or theoretically. Experiments were carried out using the avian malaria parasite Plasmodium relictum and its natural vector in the field, the mosquito Culex pipiens. Both innate immune responses (number and type of circulating haemocytes) and Plasmodium susceptibility (prevalence and burden) were quantified in seven- and 17-day old females. Whether immunity or Plasmodium susceptibility are modulated by the previous blood feeding history of the mosquito was also investigated. To ensure repeatability, two different experimental blocks were carried out several weeks apart. Haemocyte numbers decrease drastically as the mosquitoes age. Despite this, older mosquitoes are significantly more resistant to a Plasmodium infection than their younger counterparts. Crucially, however, the age effect is entirely reversed when old mosquitoes have taken one previous non-infected blood meal. The results agree with previous studies showing that older insects are often more resistant to infections than younger ones. These results suggest that structural and functional alterations in mosquito physiology with age may be more important than immunity in determining the probability of a Plasmodium infection in old mosquitoes. Possible explanations for why the effect is reversed in blood-fed mosquitoes are discussed. The reversal of the age effect in blood fed mosquitoes implies that age is unlikely to have a

  10. 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

  11. Avian cholera in Nebraska's Rainwater Basin

    Science.gov (United States)

    Windingstad, R.M.; Hurt, J.J.; Trout, A.K.; Cary, J.

    1984-01-01

    The first report of avian cholera in North America occurred in northwestern Texas in winter 1944 (Quortrup et al. 1946). In 1975, mortality from avian cholera occurred for the first time in waterfowl in the Rainwater Basin of Nebraska when an estimated 25,000 birds died (Zinkl et al. 1977). Avian cholera has continued to cause mortality in wild birds in specific areas of the Basin each spring since. Losses of waterfowl from avian cholera continue to be much greater in some of the wetlands in the western part of the Basin than in the east. Several wetlands in the west have consistently higher mortality and are most often the wetlands where initial mortality is noticed each spring (Figure 1). The establishment of this disease in Nebraska is of considerable concern because of the importance of the Rainwater Basin as a spring staging area for waterfowl migrating to their breeding grounds. The wetlands in this area are on a major migration route used by an estimated 5 to 9 million ducks and several hundred thousand geese. A large portion of the western mid-continental greater white-fronted goose (Anser albifrons) population stage in the Basin each spring. Occasionally, whooping cranes (Grus americana) use these wetlands during migration, and lesser sandhill cranes (Grus canadensis) staging on the nearby Platte River sometimes use wetlands where avian cholera occurs (Anonymous 1981). Our objectives were to determine whether certain water quality variables in the Rainwater Basin differed between areas of high and low avian cholera incidence. These results would then be used for laboratory studies involving the survivability of Pasteurella multocida, the causative bacterium of avian cholera. Those studies will be reported elsewhere.

  12. An ultra-high field strength MR image-guided robotic needle delivery system for in-bore small animal interventions.

    Science.gov (United States)

    Gravett, Matthew; Cepek, Jeremy; Fenster, Aaron

    2017-11-01

    The purpose of this study was to develop and validate an image-guided robotic needle delivery system for accurate and repeatable needle targeting procedures in mouse brains inside the 12 cm inner diameter gradient coil insert of a 9.4 T MR scanner. Many preclinical research techniques require the use of accurate needle deliveries to soft tissues, including brain tissue. Soft tissues are optimally visualized in MR images, which offer high-soft tissue contrast, as well as a range of unique imaging techniques, including functional, spectroscopy and thermal imaging, however, there are currently no solutions for delivering needles to small animal brains inside the bore of an ultra-high field MR scanner. This paper describes the mechatronic design, evaluation of MR compatibility, registration technique, mechanical calibration, the quantitative validation of the in-bore image-guided needle targeting accuracy and repeatability, and demonstrated the system's ability to deliver needles in situ. Our six degree-of-freedom, MR compatible, mechatronic system was designed to fit inside the bore of a 9.4 T MR scanner and is actuated using a combination of piezoelectric and hydraulic mechanisms. The MR compatibility and targeting accuracy of the needle delivery system are evaluated to ensure that the system is precisely calibrated to perform the needle targeting procedures. A semi-automated image registration is performed to link the robot coordinates to the MR coordinate system. Soft tissue targets can be accurately localized in MR images, followed by automatic alignment of the needle trajectory to the target. Intra-procedure visualization of the needle target location and the needle were confirmed through MR images after needle insertion. The effects of geometric distortions and signal noise were found to be below threshold that would have an impact on the accuracy of the system. The system was found to have negligible effect on the MR image signal noise and geometric distortion

  13. Prefrontal Neurons Represent Motion Signals from Across the Visual Field But for Memory-Guided Comparisons Depend on Neurons Providing These Signals.

    Science.gov (United States)

    Wimmer, Klaus; Spinelli, Philip; Pasternak, Tatiana

    2016-09-07

    Visual decisions often involve comparisons of sequential stimuli that can appear at any location in the visual field. The lateral prefrontal cortex (LPFC) in nonhuman primates, shown to play an important role in such comparisons, receives information about contralateral stimuli directly from sensory neurons in the same hemisphere, and about ipsilateral stimuli indirectly from neurons in the opposite hemisphere. This asymmetry of sensory inputs into the LPFC poses the question of whether and how its neurons incorporate sensory information arriving from the two hemispheres during memory-guided comparisons of visual motion. We found that, although responses of individual LPFC neurons to contralateral stimuli were stronger and emerged 40 ms earlier, they carried remarkably similar signals about motion direction in the two hemifields, with comparable direction selectivity and similar direction preferences. This similarity was also apparent around the time of the comparison between the current and remembered stimulus because both ipsilateral and contralateral responses showed similar signals reflecting the remembered direction. However, despite availability in the LPFC of motion information from across the visual field, these "comparison effects" required for the comparison stimuli to appear at the same retinal location. This strict dependence on spatial overlap of the comparison stimuli suggests participation of neurons with localized receptive fields in the comparison process. These results suggest that while LPFC incorporates many key aspects of the information arriving from sensory neurons residing in opposite hemispheres, it continues relying on the interactions with these neurons at the time of generating signals leading to successful perceptual decisions. Visual decisions often involve comparisons of sequential visual motion that can appear at any location in the visual field. We show that during such comparisons, the lateral prefrontal cortex (LPFC) contains

  14. Retrospective 5-year analysis of MR-guided biopsies in a low-field MR system; Retrospektive Analyse der 5-jahres-Ergebnisse von MRT-gesteuerten Biopsien im Niederfeldsystem

    Energy Technology Data Exchange (ETDEWEB)

    Zangos, Stephan; Mueller, C.; Mayer, F.; Naguib, N.N.; Nour-Eldin, N.E.A.; Herzog, C.; Hammerstingl, R.M.; Thalhammer, A.; Mack, M.G.; Vogl, T.J.; Eichler, K. [Inst. fuer Diagnostische und Interventionelle Radiologie, J.-W.-Goethe-Univ. Frankfurt (Germany); Hansmann, M.L. [Senckenbergisches Inst. fuer Pathologie, J.-W.-Goethe-Univ. Frankfurt (Germany)

    2009-07-15

    Purpose: The purpose of this study was to evaluate the safety and clinical value of MR-guided biopsies in an open 0.2 T low-field system. Materials and methods: A total of 322 patients with suspicious lesions of different body regions were biopsied in a low-field MRI system (0.2 T, Concerto, Siemens). The procedures were guided using T1-weighted Flash sequences (TR/TE = 100/9; 70 ). The lesions were repeatedly biopsied using the coaxial technique with a 15-gauge (diameter 2 mm) puncture needle. Complications and biopsy findings were analyzed retrospectively. Results: In all cases the biopsy procedures were successfully performed with MR guidance. In 298 patients diagnosis was able to be confirmed on the basis of the probes. The clinical follow-up showed that in 24 patients the lesions were missed by MR-guided biopsy. From this a sensitivity of 86%, a specificity of 87% and an accuracy of 93% were calculated. In two patients major complications were observed (morbidity rate 0.6%). Conclusion: MR-guided biopsy can be performed safely and precisely in a low-field MR system and are a supplement to US or CT-guided biopsies. (orig.)

  15. Avian Flu Epidemic 2003: Public health consequences. Executive summary

    NARCIS (Netherlands)

    Bosman A; Mulder YM; Leeuw JRJ de; Meijer A; Du Ry van Beest Holle M; Kamst RA; Velden PG van der; Conyn-van Spaendonck MAE; Koopmans MPG; Ruijten MWMM; Instituut voor Psychotrauma; CIE; MGO; LIS

    2004-01-01

    Executive summary Avian flu epidemic 2003: public health consequences.Risk factors, health, well-being, health care needs and preventive measures during the H7N7 avian flu outbreak control in the Netherlands.An estimated thousand people, possibly more have been infected with avian flu during the

  16. 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.

  17. Avian metapneumovirus subgroup C infection in chickens, China.

    Science.gov (United States)

    Wei, Li; Zhu, Shanshan; Yan, Xv; Wang, Jing; Zhang, Chunyan; Liu, Shuhang; She, Ruiping; Hu, Fengjiao; Quan, Rong; Liu, Jue

    2013-07-01

    Avian metapneumovirus causes acute respiratory tract infection and reductions in egg production in various avian species. We isolated and characterized an increasingly prevalent avian metapneumovirus subgroup C strain from meat-type commercial chickens with severe respiratory signs in China. Culling of infected flocks could lead to economic consequences.

  18. Avian Metapneumovirus Subgroup C Infection in Chickens, China

    OpenAIRE

    Wei, Li; Zhu, Shanshan; Yan, Xv; Wang, Jing; Zhang, Chunyan; Liu, Shuhang; She, Ruiping; Hu, Fengjiao; Quan, Rong; Liu, Jue

    2013-01-01

    Avian metapneumovirus causes acute respiratory tract infection and reductions in egg production in various avian species. We isolated and characterized an increasingly prevalent avian metapneumovirus subgroup C strain from meat-type commercial chickens with severe respiratory signs in China. Culling of infected flocks could lead to economic consequences.

  19. Deforestation and avian infectious diseases

    Science.gov (United States)

    Sehgal, R. N. M.

    2010-01-01

    In this time of unprecedented global change, infectious diseases will impact humans and wildlife in novel and unknown ways. Climate change, the introduction of invasive species, urbanization, agricultural practices and the loss of biodiversity have all been implicated in increasing the spread of infectious pathogens. In many regards, deforestation supersedes these other global events in terms of its immediate potential global effects in both tropical and temperate regions. The effects of deforestation on the spread of pathogens in birds are largely unknown. Birds harbor many of the same types of pathogens as humans and in addition can spread infectious agents to humans and other wildlife. It is thought that avifauna have gone extinct due to infectious diseases and many are presently threatened, especially endemic island birds. It is clear that habitat degradation can pose a direct threat to many bird species but it is uncertain how these alterations will affect disease transmission and susceptibility to disease. The migration and dispersal of birds can also change with habitat degradation, and thus expose populations to novel pathogens. Some recent work has shown that the results of landscape transformation can have confounding effects on avian malaria, other haemosporidian parasites and viruses. Now with advances in many technologies, including mathematical and computer modeling, genomics and satellite tracking, scientists have tools to further research the disease ecology of deforestation. This research will be imperative to help predict and prevent outbreaks that could affect avifauna, humans and other wildlife worldwide. PMID:20190120

  20. Deforestation and avian infectious diseases.

    Science.gov (United States)

    Sehgal, R N M

    2010-03-15

    In this time of unprecedented global change, infectious diseases will impact humans and wildlife in novel and unknown ways. Climate change, the introduction of invasive species, urbanization, agricultural practices and the loss of biodiversity have all been implicated in increasing the spread of infectious pathogens. In many regards, deforestation supersedes these other global events in terms of its immediate potential global effects in both tropical and temperate regions. The effects of deforestation on the spread of pathogens in birds are largely unknown. Birds harbor many of the same types of pathogens as humans and in addition can spread infectious agents to humans and other wildlife. It is thought that avifauna have gone extinct due to infectious diseases and many are presently threatened, especially endemic island birds. It is clear that habitat degradation can pose a direct threat to many bird species but it is uncertain how these alterations will affect disease transmission and susceptibility to disease. The migration and dispersal of birds can also change with habitat degradation, and thus expose populations to novel pathogens. Some recent work has shown that the results of landscape transformation can have confounding effects on avian malaria, other haemosporidian parasites and viruses. Now with advances in many technologies, including mathematical and computer modeling, genomics and satellite tracking, scientists have tools to further research the disease ecology of deforestation. This research will be imperative to help predict and prevent outbreaks that could affect avifauna, humans and other wildlife worldwide.

  1. Distal locking using an electromagnetic field-guided computer-based real-time system for orthopaedic trauma patients.

    Science.gov (United States)

    Langfitt, Maxwell K; Halvorson, Jason J; Scott, Aaron T; Smith, Beth P; Russell, Gregory B; Jinnah, Riyaz H; Miller, Anna N; Carroll, Eben A

    2013-07-01

    To compare the efficacy of distal interlocking during intramedullary nailing using a freehand technique versus an electromagnetic field real-time system (EFRTS). A prospective, randomized controlled trial. Level I academic trauma center. Patients older than 18 years who sustained a femoral or tibial shaft fracture amenable to antegrade intramedullary nailing were prospectively enrolled between August 2010 and November 2011. Exclusion criteria included injuries requiring retrograde nailing and open wounds near the location of the distal interlocks (distal third of the femur, knee, or distal tibia). Each patient had 2 distal interlocking screws placed: one using the freehand method and the other using EFRTS. Techniques were compared on procedural time and number of interlocking screw misses. Two time points were measured: time 1 (time to find perfect circles/time from wand placement to drill initiation) and time 2 (drill initiation until completion of interlocking placement). Twenty-four tibia and 24 femur fractures were studied. EFRTS proved faster at times 1 and 2 (P < 0.0001 and P < 0.0002) and total time (P < 0.0001). This difference was larger for junior residents, though reached statistical significance for senior residents. Senior residents were faster with the freehand technique compared with junior residents (P < 0.004), but the 2 were similar using EFRTS (P = 0.41). The number of misses was higher with free hand compared with EFRTS (P = 0.02). These results suggest that EFRTS is faster than the traditional freehand technique and results in fewer screw misses. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

  2. A field guide for the assessment of erosion, sediment transport, and deposition in incised channels of the southwestern United States

    Science.gov (United States)

    Parker, John T.C.

    2000-01-01

    Deeply incised channels, commonly called arroyos, are a typical feature of the dry alluvium-filled valleys of the southwestern United States. Unlike many geological processes that operate over millions of years, the formation of many miles of arroyos is one that took place in a little more than a century. Most arroyos in the region began to form in the late 19th century. Because dry landscapes change so quickly, they present society with special problems. Rapid expansion of channels by headcut migration, deepening, and widening causes loss of productive agricultural and commercial lands and threatens infrastructure such as roads, bridges, and buildings. High rates of sedimentation shorten the life of reservoirs, clog culverts, and fill stream channels to the extent that they can no longer contain streamflow within their banks. This report presents an explanation of erosional and depositional processes in desert landscapes, especially those characterized by incised channels, for the use of those who use, manage, and live on such lands. The basic principles of erosion, sediment transport, and deposition are presented including the formation of sediment, the forces that erode and transport it, the forces that resist its erosion and transport, and the conditions that cause it to be deposited. The peculiarities of sedimentation processes in the Southwest include the infrequent and variable precipitation, the geological setting, and the sparseness of vegetation. A classification system for incised channels that is intended for users who do not necessarily have a background in fluvial hydrology has been developed and is presented in this report. The classification system is intended to enable a user to classify a reach of channel quickly on the basis of field observations. The system is based on the shape and condition of channels and on the sedimentation processes that are predominantly responsible for those conditions. Because those processes are controlled by

  3. A field guide for selecting the most appropriate treatment in sagebrush and pinon-juniper ecosystems in the Great Basin: Evaluating resilience to disturbance and resistance to invasive annual grasses, and predicting vegetation response

    Science.gov (United States)

    Richard F. Miller; Jeanne C. Chambers; Mike Pellant

    2014-01-01

    This field guide identifies seven primary components that largely determine resilience to disturbance, as well as resistance to invasive grasses and plant succession following treatment of areas of concern. The primary components are (1) characteristics of the ecological site, (2) current vegetation prior to treatment, (3) disturbance history, (4) type, timing, and...

  4. A field guide for rapid assessment of post-wildfire recovery potential in sagebrush and pinon-juniper ecosystems in the Great Basin: Evaluating resilience to disturbance and resistance to invasive annual grasses and predicting vegetation response

    Science.gov (United States)

    Richard F. Miller; Jeanne C. Chambers; Mike Pellant

    2015-01-01

    This field guide provides a framework for rapidly evaluating post-fire resilience to disturbance, or recovery potential, and resistance to invasive annual grasses, and for determining the need and suitability of the burned area for seeding. The framework identifies six primary components that largely determine resilience to disturbance, resistance to invasive grasses,...

  5. Origin and evolution of avian microchromosomes.

    Science.gov (United States)

    Burt, D W

    2002-01-01

    The origin of avian microchromosomes has long been the subject of much speculation and debate. Microchromosomes are a universal characteristic of all avian species and many reptilian karyotypes. The typical avian karyotype contains about 40 pairs of chromosomes and usually 30 pairs of small to tiny microchromosomes. This characteristic karyotype probably evolved 100-250 million years ago. Once the microchromosomes were thought to be a non-essential component of the avian genome. Recent work has shown that even though these chromosomes represent only 25% of the genome; they encode 50% of the genes. Contrary to popular belief, microchromosomes are present in a wide range of vertebrate classes, spanning 400-450 million years of evolutionary history. In this paper, comparative gene mapping between the genomes of chicken, human, mouse and zebrafish, has been used to investigate the origin and evolution of avian microchromosomes during this period. This analysis reveals evidence for four ancient syntenies conserved in fish, birds and mammals for over 400 million years. More than half, if not all, microchromosomes may represent ancestral syntenies and at least ten avian microchromosomes are the product of chromosome fission. Birds have one of the smallest genomes of any terrestrial vertebrate. This is likely to be the product of an evolutionary process that minimizes the DNA content (mostly through the number of repeats) and maximizes the recombination rate of microchromosomes. Through this process the properties (GC content, DNA and repeat content, gene density and recombination rate) of microchromosomes and macrochromosomes have diverged to create distinct chromosome types. An ancestral genome for birds likely had a small genome, low in repeats and a karyotype with microchromosomes. A "Fission-Fusion Model" of microchromosome evolution based on chromosome rearrangement and minimization of repeat content is discussed. Copyright 2002 S. Karger AG, Basel

  6. Ribosomal RNA gene functioning in avian oogenesis.

    Science.gov (United States)

    Koshel, Elena; Galkina, Svetlana; Saifitdinova, Alsu; Dyomin, Alexandr; Deryusheva, Svetlana; Gaginskaya, Elena

    2016-12-01

    Despite long-term exploration into ribosomal RNA gene functioning during the oogenesis of various organisms, many intriguing problems remain unsolved. In this review, we describe nucleolus organizer region (NOR) activity in avian oocytes. Whereas oocytes from an adult avian ovary never reveal the formation of the nucleolus in the germinal vesicle (GV), an ovary from juvenile birds possesses both nucleolus-containing and non-nucleolus-containing oocytes. The evolutionary diversity of oocyte NOR functioning and the potential non-rRNA-related functions of the nucleolus in oocytes are also discussed.

  7. Quantification of Force and Torque Applied by a High-Field Magnetic Resonance Imaging System on an Ultrasonic Motor for MRI-Guided Robot-Assisted Interventions

    Directory of Open Access Journals (Sweden)

    Peyman Shokrollahi

    2017-09-01

    Full Text Available The risk of accidental dislodgement of robot-operated surgical mechanisms can lead to morbidity or mortality. The force and torque applied by a 3.0-tesla scanner on an ultrasonic motor are not fully known. The force and torque may displace the motor, which is not fully magnetic resonance imaging (MRI-compatible but can be safely used in MR environments. A suspension apparatus was designed to measure the angles of deflection and rotation applied to the motor by MR magnetic fields. Three orientations and two power states of the motor were assessed inside the MR bore. The displacement force and torque were measured at eight locations with respect to the bore. The displacement force on the motor from 10 cm outside the magnet bore to 20 cm inside the bore ranged from 3 to 7 gF. The experimental measurements are in agreement with the theoretical values. Running the motor altered the force by 1 gF. The force does not significantly change when the MRI scanner is on. Considerable displacement force is applied to the motor, and no deflection torque is observed. Quantified values can be used to solve dynamic equations for robotic mechanisms intended for MRI-guided operations.

  8. First patients treated with a 1.5 T MRI-Linac: clinical proof of concept of a high-precision, high-field MRI guided radiotherapy treatment

    Science.gov (United States)

    Raaymakers, B. W.; Jürgenliemk-Schulz, I. M.; Bol, G. H.; Glitzner, M.; Kotte, A. N. T. J.; van Asselen, B.; de Boer, J. C. J.; Bluemink, J. J.; Hackett, S. L.; Moerland, M. A.; Woodings, S. J.; Wolthaus, J. W. H.; van Zijp, H. M.; Philippens, M. E. P.; Tijssen, R.; Kok, J. G. M.; de Groot-van Breugel, E. N.; Kiekebosch, I.; Meijers, L. T. C.; Nomden, C. N.; Sikkes, G. G.; Doornaert, P. A. H.; Eppinga, W. S. C.; Kasperts, N.; Kerkmeijer, L. G. W.; Tersteeg, J. H. A.; Brown, K. J.; Pais, B.; Woodhead, P.; Lagendijk, J. J. W.

    2017-12-01

    The integration of 1.5 T MRI functionality with a radiotherapy linear accelerator (linac) has been pursued since 1999 by the UMC Utrecht in close collaboration with Elekta and Philips. The idea behind this integrated device is to offer unrivalled, online and real-time, soft-tissue visualization of the tumour and the surroundings for more precise radiation delivery. The proof of concept of this device was given in 2009 by demonstrating simultaneous irradiation and MR imaging on phantoms, since then the device has been further developed and commercialized by Elekta. The aim of this work is to demonstrate the clinical feasibility of online, high-precision, high-field MRI guidance of radiotherapy using the first clinical prototype MRI-Linac. Four patients with lumbar spine bone metastases were treated with a 3 or 5 beam step-and-shoot IMRT plan. The IMRT plan was created while the patient was on the treatment table and based on the online 1.5 T MR images; pre-treatment CT was deformably registered to the online MRI to obtain Hounsfield values. Bone metastases were chosen as the first site as these tumors can be clearly visualized on MRI and the surrounding spine bone can be detected on the integrated portal imager. This way the portal images served as an independent verification of the MRI based guidance to quantify the geometric precision of radiation delivery. Dosimetric accuracy was assessed post-treatment from phantom measurements with an ionization chamber and film. Absolute doses were found to be highly accurate, with deviations ranging from 0.0% to 1.7% in the isocenter. The geometrical, MRI based targeting as confirmed using portal images was better than 0.5 mm, ranging from 0.2 mm to 0.4 mm. In conclusion, high precision, high-field, 1.5 T MRI guided radiotherapy is clinically feasible.

  9. 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.

  10. 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.

  11. 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. Published by Elsevier Ltd.

  12. Remote Sensing Field Guide - Desert

    Science.gov (United States)

    1991-09-01

    kankar, kunkur, silcrete, gres polymorphe, porcellanite, sarsen, puddingstone, meulieres. SUMMARY ShEET - DESER ’ DURICRUSTS SPECIAL AND MINOR FEATURES...especially in Tunisia, Algeria, and in the coastal Namib Desert (Africa); in the Rajasthan Desert of west India; in various Middle Eastern deserts...Iran, and in crystalline rocks (granites and metamorphic rocks) in the southern coast- al Namib Desert of southwest Africa. All of these occurrences

  13. Walkthrough screening evaluation field guide

    International Nuclear Information System (INIS)

    Eder, S.J.; Eli, M.W.; Salmon, M.W.

    1993-11-01

    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

  14. Effects of drought on avian community structure

    Science.gov (United States)

    Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Curtis H. Flather; Patrick D. Culbert; Brian D. Wardlow; Volker C. Radeloff

    2010-01-01

    Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioural traits, what time periods and indicators of drought are most...

  15. 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...

  16. New Avian Hepadnavirus in Palaeognathous Bird, Germany

    NARCIS (Netherlands)

    Jo, Wendy K; Pfankuche, Vanessa M; Petersen, Henning; Frei, Samuel; Kummrow, Maya; Lorenzen, Stephan; Ludlow, Martin; Metzger, Julia; Baumgärtner, Wolfgang; Osterhaus, Albert; van der Vries, Erhard

    2017-01-01

    In 2015, we identified an avian hepatitis B virus associated with hepatitis in a group of captive elegant-crested tinamous (Eudromia elegans) in Germany. The full-length genome of this virus shares <76% sequence identity with other avihepadnaviruses. The virus may therefore be considered a new

  17. 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...

  18. Viral vectors for avian influenza vaccines

    Science.gov (United States)

    Prior to 2003, vaccines against avian influenza (AI) had limited, individual country or regional use in poultry. In late 2003, H5N1 high pathogenicity (HP) AI spread from China to multiple Southeast Asian countries, and to Europe during 2005 and Africa during 2006, challenging governments and all p...

  19. the Avian Park Service Learning Centre story

    African Journals Online (AJOL)

    The Ukwanda Centre for Rural Health (UCRH) opened in 2001, followed 10 years later by the establishment of the Ukwanda Rural Clinical School in one of the rural health districts of the Western Cape. This paper relates the journey of the Faculty with the underserviced community of Avian Park through the provision of ...

  20. Presumptive diagnosis of Avian encephalomyelitis in Japanese ...

    African Journals Online (AJOL)

    A report of Avian encephalomyelitis outbreak in two flocks of adult Japanese quail is presented. High mortalities, tremor, ataxia and lateral recumbency were the prominent clinical signs observed. Absence of gross pathology and microscopic lesions of gliosis, neuronal degeneration, meningitis, congested blood vessel with ...

  1. The genetics and evolution of avian migration

    NARCIS (Netherlands)

    Pulido, F.

    2007-01-01

    One of the characteristics of avian migration is its variability within and among species. Variation in migratory behavior, and in physiological and morphological adaptations to migration, is to a large extent due to genetic differences. Comparative studies suggest that migratory behavior has

  2. Solar activity affects avian timing of reproduction

    NARCIS (Netherlands)

    Visser, M.E.; Sanz, J.J.

    2009-01-01

    Avian timing of reproduction is strongly affected by ambient temperature. Here we show that there is an additional effect of sunspots on laying date, from five long-term population studies of great and blue tits (Parus major and Cyanistes caeruleus), demonstrating for the first time that solar

  3. Vocal communication in an avian hybrid zone

    NARCIS (Netherlands)

    Hartog, Paula Maria den

    2008-01-01

    Avian vocalizations function in mate attraction and territorial defence. Vocalizations can act as behavioural barriers and play an important role in speciation processes. Hybrid zones illustrate behavioural barriers are not always impermeable and provide a natural laboratory to examine the role of

  4. Fossil avian eggshell preserves ancient DNA

    DEFF Research Database (Denmark)

    Oskam, Charlotte L; Haile, James Seymour; 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. 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

  6. Measuring steroid hormones in avian eggs

    NARCIS (Netherlands)

    Von Engelhardt, Nikolaus; Groothuis, Ton G. G.; Bauchinger, U; Goymann, W; JenniEiermann, S

    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

  7. WE-G-BRB-08: TG-51 Calibration of First Commercial MRI-Guided IMRT System in the Presence of 0.35 Tesla Magnetic Field.

    Science.gov (United States)

    Goddu, S; Green, O Pechenaya; Mutic, S

    2012-06-01

    The first real-time-MRI-guided radiotherapy system has been installed in a clinic and it is being evaluated. Presence of magnetic field (MF) during radiation output calibration may have implications on ionization measurements and there is a possibility that standard calibration protocols may not be suitable for dose measurements for such devices. In this study, we evaluated whether a standard calibration protocol (AAPM- TG-51) is appropriate for absolute dose measurement in presence of MF. Treatment delivery of the ViewRay (VR) system is via three 15,000Ci Cobalt-60 heads positioned 120-degrees apart and all calibration measurements were done in the presence of 0.35T MF. Two ADCL- calibrated ionization-chambers (Exradin A12, A16) were used for TG-51 calibration. Chambers were positioned at 5-cm depth, (SSD=105cm: VR's isocenter), and the MLC leaves were shaped to a 10.5cm × 10.5 cm field size. Percent-depth-dose (PDD) measurements were performed for 5 and 10 cm depths. Individual output of each head was measured using the AAPM- TG51 protocol. Calibration accuracy for each head was subsequently verified by Radiological Physics Center (RPC) TLD measurements. Measured ion-recombination (Pion) and polarity (Ppol) correction factors were less-than 1.002 and 1.006, respectively. Measured PDDs agreed with BJR-25 within ±0.2%. Maximum dose rates for the reference field size at VR's isocenter for heads 1, 2 and 3 were 1.445±0.005, 1.446±0.107, 1.431±0.006 Gy/minute, respectively. Our calibrations agreed with RPC- TLD measurements within ±1.3%, ±2.6% and ±2.0% for treatment-heads 1, 2 and 3, respectively. At the time of calibration, mean activity of the Co-60 sources was 10,800Ci±0.1%. This study shows that the TG- 51 calibration is feasible in the presence of 0.35T MF and the measurement agreement is within the range of results obtainable for conventional treatment machines. Drs. Green, Goddu, and Mutic served as scientific consultants for ViewRay, Inc. Dr. Mutic

  8. 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,…

  9. Reconstruction of a bipolar magnetic signature in an earthward jet in the tail: Flux rope or 3D guide-field reconnection?

    Science.gov (United States)

    Hasegawa, H.; Nakamura, R.; Fujimoto, M.; Sergeev, V. A.; Lucek, E. A.; RèMe, H.; Khotyaintsev, Y.

    2007-11-01

    Southward-then-northward magnetic perturbations are often seen in the tail plasma sheet, along with earthward jets, but the generation mechanism of such bipolar Bz (magnetic flux rope created through multiple X-line reconnection, transient reconnection, or else) has been controversial. At ˜2313 UT on 13 August 2002, Cluster encountered a bipolar Bz at the leading edge of an earthward jet, with one of the four spacecraft in the middle of the current sheet. Application to this bipolar signature of Grad-Shafranov (GS) reconstruction, the technique for recovery of two-dimensional (2D) magnetohydrostatic structures, suggests that a flux rope with diameter of ˜2 RE was embedded in the jet. To investigate the validity of the GS results, the technique is applied to synthetic data from a three-dimensional (3D) MHD simulation, in which a bipolar Bz can be produced through localized (3D) reconnection in the presence of guide field By (Shirataka et al., 2006) without invoking multiple X-lines. A flux rope-type structure, which does not in fact exist in the simulation, is reconstructed but with a shape elongated in the jet direction. Unambiguous identification of a mechanism that leads to an observed bipolar Bz thus seems difficult based on the topological property in the GS maps. We however infer that a flux rope was responsible for the bipolar pulse in this particular Cluster event, because the recovered magnetic structure is roughly circular, suggesting a relaxed and minimum energy state. Our results also indicate that one has to be cautious about interpretation of some (e.g., force-free, or magnetohydrostatic) model-based results.

  10. 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

  11. Efficacy of an avian colibacillosis live vaccine for layer breeder in Japan

    OpenAIRE

    UOTANI, Yusuke; KITAHARA, Rie; IMAI, Takahiko; TSUTSUMI, Nobuyuki; SASAKAWA, Chihiro; NAGAI, Shinya; NAGANO, Tetsuji

    2017-01-01

    Colibacillosis is one of an economically significant disease in the poultry industry, especially for meat breed chickens. Recently it has become a serious problem for layer especially when the birds start laying and also at the later stage of laying. In Japan, the productivity of field laying hens improved when the ?crp avian colibacillosis live vaccine (?Gall N tect CBL?) was used. The survival rate and egg laying rate increased during almost all of the laying period when compared with the c...

  12. Avian infectious bronchitis virus in Brazil: a highly complex virus meets a highly susceptible host population

    Directory of Open Access Journals (Sweden)

    PE Brandão

    2010-06-01

    Full Text Available Infectious bronchitis (IB is a highly aggressive disease for poultry in terms of symptoms and economic losses, and the control of this disease is difficult if flocks are not protected against type-specific challenges by the Avian infectious bronchitis virus (IBV. This article summarizes data presented by the author at the Workshop on Infectious Bronchitis 2009 on IB and IBV, including future developments on the field.

  13. Effects of oil on avian reproduction: A review and discussion

    Science.gov (United States)

    Albers, P.H.; Rosie, Don; Barnes, Stephen N.

    1983-01-01

    Oil pollution is a highly visible form of environmental contamination that affects avian reproduction in a variety of ways. Plumage oiling causes widespread and locally severe mortality of adult birds. Egg oiling can be a serious hazard for bird embryos but only a few field observationons of this have been reported. Oil ingestion seldom kills birds directly but it causes sublethal change~ in the bodily functions and behavior of adults and nestlings. Studies of the effects of oil on avian reproduction have produced varied and, in ingestion studies, sometimes conflicting results because of inconsistent experimental design and the use of different test species and types of oil. Field experimentation with the sublethal effects of ingested oil on avian reproduction has been limited. Simulation modelling of seabird populations has shown that (l) an occasional decrease in survival of breeding adults will have a greater impact on seabird populations than an occasional decrease in reproductive success, and (2) populations of long-lived seabirds with low reproductive potential have great difficulty recovering from high one-time mortality when experiencing even small sustained annual decreases in either natality or breeding adult survival. The impact of oil-related decreases in survival or reproduction will be more noticeable at the local or colony level than at the regional or species level. Immigration, surplus breeders, and possible compensatory changes in natality and mortality resulting from population reductions usually prevent local population reductions from lasting very long (unless the species is rare or at the edge of its range). A study of west European seabird populations indicates that the natural annual mortality of the region greatly exceeds the annual mortality due to plumage oiling; effects of oil ingestion and egg oiling were not measured but were thought to be less than the mortality from plu~age oiling. Oil-related mortality, even if in addition to

  14. Neutron guide

    Science.gov (United States)

    Greene, Geoffrey L.

    1999-01-01

    A neutron guide in which lengths of cylindrical glass tubing have rectangular glass plates properly dimensioned to allow insertion into the cylindrical glass tubing so that a sealed geometrically precise polygonal cross-section is formed in the cylindrical glass tubing. The neutron guide provides easier alignment between adjacent sections than do the neutron guides of the prior art.

  15. Identification of high risk areas for avian influenza outbreaks in California using disease distribution models.

    Directory of Open Access Journals (Sweden)

    Jaber Belkhiria

    Full Text Available The coexistence of different types of poultry operations such as free range and backyard flocks, large commercial indoor farms and live bird markets, as well as the presence of many areas where wild and domestic birds co-exist, make California susceptible to avian influenza outbreaks. The 2014-2015 highly pathogenic Avian Influenza (HPAI outbreaks affecting California and other states in the United States have underscored the need for solutions to protect the US poultry industry against this devastating disease. We applied disease distribution models to predict where Avian influenza is likely to occur and the risk for HPAI outbreaks is highest. We used observations on the presence of Low Pathogenic Avian influenza virus (LPAI in waterfowl or water samples at 355 locations throughout the state and environmental variables relevant to the disease epidemiology. We used two algorithms, Random Forest and MaxEnt, and two data-sets Presence-Background and Presence-Absence data. The models performed well (AUCc > 0.7 for testing data, particularly those using Presence-Background data (AUCc > 0.85. Spatial predictions were similar between algorithms, but there were large differences between the predictions with Presence-Absence and Presence-Background data. Overall, predictors that contributed most to the models included land cover, distance to coast, and broiler farm density. Models successfully identified several counties as high-to-intermediate risk out of the 8 counties with observed outbreaks during the 2014-2015 HPAI epizootics. This study provides further insights into the spatial epidemiology of AI in California, and the high spatial resolution maps may be useful to guide risk-based surveillance and outreach efforts.

  16. 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

    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 conservation—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 do not

  17. 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 that the ......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...... that the placement of perches increased local hunting activity of at least the Black Shouldered Kite but there were no obvious effects on rodent population size or survival. In a single field where avian predation was prevented by covering the field with a net, an increase in survival was observed. The opposite...

  18. Avian brains: Insights from development, behaviors and evolution.

    Science.gov (United States)

    Nomura, Tadashi; Izawa, Ei-Ichi

    2017-05-01

    Birds are an extensively specialized animal group with unique anatomical, physiological and ecological characteristics. Sophisticated social behaviors and remarkable cognitive abilities are present in several avian lineages, driven by their enlarged brains and intricate neural networks. These unique traits could be a result of adaptive evolution under the wide range of environmental constraints; however, the intrinsic mechanisms of avian brain development and evolution remain unclear. Here, we introduce recent findings regarding developmental aspects of avian brain organization and neuronal networks for specific avian behaviors, which provide an insight into the link between the evolution of brain development and complex cognitive functions. © 2017 Japanese Society of Developmental Biologists.

  19. 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.

  20. Avian Circadian Organization: A Chorus of Clocks

    Science.gov (United States)

    Cassone, Vincent M

    2013-01-01

    In birds, biological clock function pervades all aspects of biology, controlling daily changes in sleep: wake, visual function, song, migratory patterns and orientation, as well as seasonal patterns of reproduction, song and migration. The molecular bases for circadian clocks are highly conserved, and it is likely the avian molecular mechanisms are similar to those expressed in mammals, including humans. The central pacemakers in the avian pineal gland, retinae and SCN dynamically interact to maintain stable phase relationships and then influence downstream rhythms through entrainment of peripheral oscillators in the brain controlling behavior and peripheral tissues. Birds represent an excellent model for the role played by biological clocks in human neurobiology; unlike most rodent models, they are diurnal, they exhibit cognitively complex social interactions, and their circadian clocks are more sensitive to the hormone melatonin than are those of nocturnal rodents. PMID:24157655

  1. Avian Radar - Is It Worth the Cost?

    Science.gov (United States)

    2012-06-01

    DC: The Federal Aviation Administration, in cooperation with the U.S. Department of Agriculture, Animal and Plant Health Inspection Service , Wildlife...Agriculture Animal and Plant Health Inspection Service Wildlife Services. York, D. L., Engeman, R. M., Cummings, J. L., Rossi, C. L., & Sinnett, D. R... Health Inspection Service , Wildlife Services. DOT/FAA/AR-09/61. (2010). Deployments of Avian Radars at Civil Airports. Springfield: National

  2. Common Avian Infection Plagued the Tyrant Dinosaurs

    Science.gov (United States)

    Wolff, Ewan D. S.; Salisbury, Steven W.; Horner, John R.; Varricchio, David J.

    2009-01-01

    Background Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name ‘Sue’) has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. Methodology/Principal Findings We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. Conclusions/Significance This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation. PMID:19789646

  3. Common avian infection plagued the tyrant dinosaurs.

    Directory of Open Access Journals (Sweden)

    Ewan D S Wolff

    Full Text Available BACKGROUND: Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue' has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. METHODOLOGY/PRINCIPAL FINDINGS: We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. CONCLUSIONS/SIGNIFICANCE: This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation.

  4. Common avian infection plagued the tyrant dinosaurs.

    Science.gov (United States)

    Wolff, Ewan D S; Salisbury, Steven W; Horner, John R; Varricchio, David J

    2009-09-30

    Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue') has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation.

  5. The Avian Transcriptome Response to Malaria Infection

    OpenAIRE

    Videvall, Elin; Cornwallis, Charlie K.; Palinauskas, Vaidas; Valki?nas, Gediminas; Hellgren, Olof

    2015-01-01

    Malaria parasites are highly virulent pathogens which infect a wide range of vertebrates. Despite their importance, the way different hosts control and suppress malaria infections remains poorly understood. With recent developments in next-generation sequencing techniques, however, it is now possible to quantify the response of the entire transcriptome to infections. We experimentally infected Eurasian siskins (Carduelis spinus) with avian malaria parasites (Plasmodium ashfordi), and used hig...

  6. Integration and Validation of Avian Radars (IVAR)

    Science.gov (United States)

    2011-07-01

    shape, density, gender ) is problematic; • Not suited to high-clutter environments (e.g., in forests, near buildings); • Health & safety issues...Fuca and the Saratoga Passage and within the rain shadow of the Olympic Mountains, NAS Whidbey Island offers high quality year round training...was to demonstrate that the digital avian radars being evaluated by the IVAR project can automatically discriminate the echoes of moving targets

  7. 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...

  8. Tracing the evolution of avian wing digits.

    Science.gov (United States)

    Xu, Xing; Mackem, Susan

    2013-06-17

    It is widely accepted that birds are a subgroup of dinosaurs, but there is an apparent conflict: modern birds have been thought to possess only the middle three fingers (digits II-III-IV) of an idealized five-digit tetrapod hand based on embryological data, but their Mesozoic tetanuran dinosaur ancestors are considered to have the first three digits (I-II-III) based on fossil evidence. How could such an evolutionary quirk arise? Various hypotheses have been proposed to resolve this paradox. Adding to the confusion, some recent developmental studies support a I-II-III designation for avian wing digits whereas some recent paleontological data are consistent with a II-III-IV identification of the Mesozoic tetanuran digits. A comprehensive analysis of both paleontological and developmental data suggests that the evolution of the avian wing digits may have been driven by homeotic transformations of digit identity, which are more likely to have occurred in a partial and piecemeal manner. Additionally, recent genetic studies in mouse models showing plausible mechanisms for central digit loss invite consideration of new alternative possibilities (I-II-IV or I-III-IV) for the homologies of avian wing digits. While much progress has been made, some advances point to the complexity of the problem and a final resolution to this ongoing debate demands additional work from both paleontological and developmental perspectives, which will surely yield new insights on mechanisms of evolutionary adaptation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. 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.

  10. Global phylogeographic limits of Hawaii's avian malaria

    Science.gov (United States)

    Beadell, J.S.; Ishtiaq, F.; Covas, R.; Melo, M.; Warren, B.H.; Atkinson, C.T.; Bensch, S.; Graves, G.R.; Jhala, Y.V.; Peirce, M.A.; Rahmani, A.R.; Fonseca, D.M.; Fleischer, R.C.

    2006-01-01

    The introduction of avian malaria (Plasmodium relictum) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite within a global ecological and evolutionary context. Using fragments of the parasite mitochondrial gene cytochrome b and the nuclear gene dihydrofolate reductase-thymidylate synthase obtained from a global survey of greater than 13 000 avian samples, we show that Hawaii's avian malaria, which can cause high mortality and is a major limiting factor for many species of native passerines, represents just one of the numerous lineages composing the morphological parasite species. The single parasite lineage detected in Hawaii exhibits a broad host distribution worldwide and is dominant on several other remote oceanic islands, including Bermuda and Moorea, French Polynesia. The rarity of this lineage in the continental New World and the restriction of closely related lineages to the Old World suggest limitations to the transmission of reproductively isolated parasite groups within the morphological species. ?? 2006 The Royal Society.

  11. Manual on brachytherapy. Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1996-01-01

    This publication is part of practical radiation safety manual series for different fields of application aimed primarily at persons handling radiation sources on a daily routine basis, which could at same time be used by the competent authorities, supporting their efforts in the radiation protection training of workers or medical assistance personnel or helping on-site management to set up local radiation protection rules. It is dedicated to brachytherapy: its application and procedures guides

  12. Efficacy of an avian colibacillosis live vaccine for layer breeder in Japan.

    Science.gov (United States)

    Uotani, Yusuke; Kitahara, Rie; Imai, Takahiko; Tsutsumi, Nobuyuki; Sasakawa, Chihiro; Nagai, Shinya; Nagano, Tetsuji

    2017-07-19

    Colibacillosis is one of an economically significant disease in the poultry industry, especially for meat breed chickens. Recently it has become a serious problem for layer especially when the birds start laying and also at the later stage of laying. In Japan, the productivity of field laying hens improved when the Δcrp avian colibacillosis live vaccine ("Gall N tect CBL") was used. The survival rate and egg laying rate increased during almost all of the laying period when compared with the control group. The improvement in productivity was clearly demonstrated by comparing the number of eggs laid per day. The use of an avian colibacillosis live vaccine proved to be cost-effective in laying hens.

  13. Characterisation and Identification of Avian Influenza Virus (AI

    Directory of Open Access Journals (Sweden)

    Dyah Ayu Hewajuli

    2008-06-01

    Full Text Available Avian Influenza is caused by Influenza A virus which is a member of Orthomyxoviridae family. Influenza A virus is enveloped single stranded RNA with eight-segmented, negative polarity and filament or oval form, 50 – 120 by 200 – 300 nm diameters. Influenza A viruses have been found to infect birds, human, pig, horse and sometimes in the other mammalian such as seal and whale. The viruses are divided into different subtypes based on the antigenic protein which covers the virus surface i.e. Haemaglutinin (HA and Neuraminidase (NA. In addition, the nomenclature of subtype virus is based on HA and NA i.e HxNx, for example H5N1, H9N2 and the others. According to pathogenic, it could be divided into two distinct groups, they are Highly Pathogenic Avian Influenza (HPAI and Low Pathogenic Avian Influenza (LPAI. The Avian Influenza viruses have been continuously occurred and spread out in some continents such us America, Europe, Africa and Asian countries. The outbreak of Avian Influenza caused high mortality on birds and it has been reported that in human case Avian Influenza subtype H5N1 virus has caused several deaths. To anticipate this condition, an effort to prevent the transmission of Avian Influenza is needed. These strategic attempts include biosecurity, depopulation, vaccination, control of virus movement, monitoring and evaluation. Laboratory diagnostic plays an important role for successful prevention, control and eradication programs of Avian Influenza. Recently, there are two diagnostic methods for Avian Influenza. They are conventional (virological diagnosis and molecular methods. The conventional method is usually used for initial diagnostic of Avian Influenza. The conventional method takes more time and more costly, whereas the molecular method is more effective than conventional method. Based on the available diagnostic technique, basically diagnostic of Avian Influenza is done by serology test, isolation and identification as well

  14. MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open high-field MRI scanner with respiratory gating

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ming; Huang, Jie; Xu, Yujun; He, Xiangmeng; Lue, Yubo; Liu, Qiang; Li, Chengli [Department of Interventional MRI, Shandong Medical Imaging Research Institute affiliated to Shandong University, Shandong Key Laboratory of Advanced Medical Imaging Technologies and Applications, Jinan, Shandong (China); Li, Lei [Qingdao Central Hospital, Department of Interventional Radiology, Qingdao, Shandong (China); Blanco Sequeiros, Roberto [Turku University Hospital, The South Western Finland Imaging Centre, Turku (Finland)

    2017-04-15

    To prospectively evaluate the feasibility, safety and accuracy of MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open MR scanner with respiratory gating. Sixty-five patients with 65 solitary pulmonary lesions underwent MR-guided percutaneous coaxial cutting needle biopsy using a 1.0-T open MR scanner with respiratory gating. Lesions were divided into two groups according to maximum lesion diameters: ≤2.0 cm (n = 31) and >2.0 cm (n = 34). The final diagnosis was established in surgery and subsequent histology. Diagnostic accuracy, sensitivity and specificity were compared between the groups using Fisher's exact test. Accuracy, sensitivity and specificity of MRI-guided percutaneous pulmonary biopsy in diagnosing malignancy were 96.9 %, 96.4 % and 100 %, respectively. Accuracy, sensitivity and specificity were 96.8 %, 96.3 % and 100 % for lesions 2.0 cm or smaller and 97.1 %, 96.4 % and 100 %, respectively, for lesions larger than 2.0 cm. There was no significant difference between the two groups (P > 0.05). Biopsy-induced complications encountered were pneumothorax in 12.3 % (8/65) and haemoptysis in 4.6 % (3/65). There were no serious complications. MRI-guided percutaneous biopsy using a 1.0-T open MR scanner with respiratory gating is an accurate and safe diagnostic technique in evaluation of pulmonary lesions. (orig.)

  15. Trying and Reflecting: Two Novice Teacher Educators' First Attempts at Guiding Pre-Service Teachers' Reflection on Literacy Field Experiences

    Science.gov (United States)

    Dennis, Danielle V.; Gelfuso, Andrea; Sweeney, Sherridon

    2018-01-01

    In Democracy and Education, Dewey aligns trying and undergoing as experience. Undergoing the consequences of trying by reflecting entails noticing and naming the details of the connections between the activity and the consequences. In this paper, we explore two novice teacher educators' first attempts at guiding pre-service teachers (PSTs)…

  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. 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.…

  18. 2 original article non-attenuation of highly pathogenic avian ...

    African Journals Online (AJOL)

    Dr Oboro VO

    Ularamu, H. G1., Ponman, S1 and Nwagbo, I2., 1 FAO Regional Laboratory for Avian Influenza and Newcastle. Disease (West and Central ... Avian influenza H5N1 represents one of the most researched viruses in laboratories world-wide in recent times with regards ..... Cayouette B. Kinetics of ultra- violet light inactivation of.

  19. High prevalence of avian malaria infection to avifauna at Cape ...

    African Journals Online (AJOL)

    This investigation was undertaken during January and February 2004, to determine the epidemiological risk of avian malaria infection to seabirds at the proposed marine animal rehabilitation complex, to be sited at Cape Receife. Despite low numbers of mosquitoes trapped, the incidence of avian malaria infections was ...

  20. 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.

  1. Avian fossils from the Early Miocene Moghra Formation of Egypt ...

    African Journals Online (AJOL)

    Avian remains from the Early Miocene (~17 Ma) Moghra Formation of Egypt include new records of 'waterbirds' (storks, herons, pelicans and allies) and a ratite. Only a single avian fossil has been previously reported from Wadi Moghra and, thus, additional knowledge of the avifauna complements previously documented ...

  2. Avian influenza, Newcastle and Gumboro disease antibodies and ...

    African Journals Online (AJOL)

    Studies on avian influenza and Newcastle disease focus on waterfowls, considered natural reservoirs of these viruses. This study surveyed avian influenza (AI), Gumboro and Newcastle disease antibodies and antigens in birds in live wild bird markets (LWBMs), live poultry markets (LPMs) and free flying in Kaduna State ...

  3. Flock-based surveillance for lowpathogenic avian influenza virus in ...

    African Journals Online (AJOL)

    Flock-based surveillance for lowpathogenic avian influenza virus in commercial breeders and layers, southwest Nigeria. ... African Journal of Infectious Diseases ... Background: Flock surveillance systems for avian influenza (AI) virus play a critical role in countries where vaccination is not practiced so as to establish the ...

  4. Avian nestling predation by endangered Mount Graham red squirrel

    Science.gov (United States)

    Claire A. Zugmeyer; John L. Koprowski

    2007-01-01

    Studies using artificial nests or remote cameras have documented avian predation by red squirrels (Tamiasciurus hudsonicus). Although several direct observations of avian predation events are known in the northern range of the red squirrel distribution, no accounts have been reported in the southern portion. We observed predation upon a hermit thrush...

  5. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ..., Killed Virus. 113.208 Section 113.208 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian Encephalomyelitis Vaccine, Killed Virus. Avian...

  6. Prevention and Treatment of Avian Influenza A Viruses in People

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  7. Avian Influenza A (H7N9) Virus

    Science.gov (United States)

    ... in People Spread of Bird Flu Viruses Between Animals and People Examples of Human Infections with Avian Influenza A ... Influenza A (H5N1) H5N1 in Birds and Other Animals H5N1 in People Public Health Threat of Highly Pathogenic Asian Avian ...

  8. Avian research in the U.S. Forest Service

    Science.gov (United States)

    Beatrice Van Horne

    2005-01-01

    Avian research in the Federal Government is in a crisis. Yes, there is a strong interest in avian research, as evidenced by the size and level of interest in this conference. But political parties increasingly see wildlife research as expendable. At the same time, the reaction to environment-friendly legislation of the 1970s and 1980s has been strong from both sides....

  9. 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...

  10. Socioeconomic Impacts of Avian Influenza on Small and Backyard ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    and compensation schemes are more difficult to enforce than in large commercial poultry farms. Moreover, small and backyard farmers have fewer reserves to cope with the financial impact of avian influenza and, possibly, greater motivation to circumvent government control measures. The Asian Partnership for Avian ...

  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

  12. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Science.gov (United States)

    2010-01-01

    ... Isolate. 113.70 Section 113.70 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or modified...

  13. Detection of avian nephritis virus and chicken astrovirus in Nigerian ...

    African Journals Online (AJOL)

    Avian nephritis virus (ANV) and chicken astrovirus (CAstV) are widely distributed in poultry flocks worldwide, causing growth retardation. However, these avian astroviruses have not been previously diagnosed in poultry species in Nigeria. Real-time reverse transcriptase-polymerase chain reaction (rRTPCR) and reverse ...

  14. Nanostructures for the development of vaccines against avian ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2018-01-12

    Jan 12, 2018 ... Photo: IDRC / Sven Torfinn. The impact of avian influenza. The livelihoods of smallholder farmers, who most frequently own poultry have been severely impacted by recent outbreaks of avian influenza (AI). The severity of the disease can range from mild to extremely severe cases with up to a 100% mortality ...

  15. 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...

  16. 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.

  17. Architectural Guide of Jordan

    DEFF Research Database (Denmark)

    2016-01-01

    Architectural and cultural guidebook for Jordan that also includes a view on the Syrian refugee situation, especially in the large UNHCR camp of Zaatari. The guide book is a preparatory study for a field trip our master studio undertook to the Hashemite Kingdom of Jordan in Fall 2016....

  18. 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,…

  19. Rust scoring guide

    NARCIS (Netherlands)

    Anonymous,

    1986-01-01

    This brief guide for identifying rust diseases of smaill grain cereals contains color photos depicting the growth stages of small grain cereal crops and provides instructions for recording rust severity and field response for stripe rust (Puccinia striiformis), stem rust (P. graminis), and leaf rust

  20. Rust scoring guide

    OpenAIRE

    Anonymous

    1986-01-01

    This brief guide for identifying rust diseases of smaill grain cereals contains color photos depicting the growth stages of small grain cereal crops and provides instructions for recording rust severity and field response for stripe rust (Puccinia striiformis), stem rust (P. graminis), and leaf rust (P. recondita).

  1. 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…

  2. Avian mycobacteriosis in companion birds: 20-year survey.

    Science.gov (United States)

    Manarolla, Giovanni; Liandris, Emmanouil; Pisoni, Giuliano; Sassera, Davide; Grilli, Guido; Gallazzi, Daniele; Sironi, Giuseppe; Moroni, Paolo; Piccinini, Renata; Rampin, Tiziana

    2009-02-02

    The causative agents of avian mycobacteriosis in pet birds are rarely identified. The aim of this study is to add information about the etiology of avian mycobacteriosis. The identification of mycobacterium species in 27 cases of avian mycobacteriosis in pet birds was investigated by polymerase chain reaction (PCR) and sequencing of a rRNA hypervariable region. Avian mycobacteriosis appeared to be an infrequent diagnosis. Interestingly, a few cases of avian mycobacteriosis were recorded in very young birds. The most commonly affected species were the canary (Serinus canarius), the Eurasian goldfinch (Carduelis carduelis) and the red siskin (Spinus cucullatus). All but one bird were infected with Mycobacterium genavense. Mycobacterium avium was identified only in one case.

  3. Assessing multiregion avian benefits from strategically targeted agricultural buffers.

    Science.gov (United States)

    Evans, Kristine O; Burger, L Wes; Riffell, Sam; Smith, Mark D

    2014-08-01

    Mounting evidence of wildlife population gains from targeted conservation practices has prompted the need to develop and evaluate practices that are integrated into production agriculture systems and targeted toward specific habitat objectives. However, effectiveness of targeted conservation actions across broader landscapes is poorly understood. We evaluated multiregion, multispecies avian densities on row-crop fields with native grass field margins (i.e., buffers) as part of the first U.S. agricultural conservation practice designed to support habitat and population recovery objectives of a national wildlife conservation initiative. We coordinated breeding season point transect surveys for 6 grassland bird species on 1151 row-crop fields with and without native grass buffers (9-37 m) in 14 U.S. states (10 ecoregions) from 2006 to 2011. In most regions, breeding season densities of 5 of 6 targeted bird species were greater in the 500-m surrounding survey points centered on fields with native grass buffers than in landscapes without buffers. Relative effect sizes were greatest for Northern Bobwhite (Colinus virginianus), Dickcissel (Spiza americana), and Field Sparrow (Spizella pusilla) in the Mississippi Alluvial Valley and Eastern Tallgrass Prairie regions. Other species (e.g., Eastern Meadowlark [Sturnella magna], Grasshopper Sparrow [Ammodramus savannarum]) exhibited inconsistent relative effect sizes. Bird densities on fields with and without buffers were greatest in the Central Mixed-grass Prairie region. Our results suggest that strategic use of conservation buffers in regions with the greatest potential for relative density increases in target species will elicit greater range-wide population response than diffuse, uninformed, and broadly distributed implementation of buffers. We recommend integrating multiple conservation practices in broader agricultural landscapes to maximize conservation effectiveness for a larger suite of species. © 2014 Society for

  4. assessment of the economic and social implications of the avian flu ...

    African Journals Online (AJOL)

    Admin

    2006-01-22

    Jan 22, 2006 ... KEYWORDS: Assessment, Economic, Social Implications, Avian Flu, Nigerian Poultry. INTRODUCTION. Avian flu is a highly infectious, contagious and zoonotic disease of man, poultry and other birds caused by the avian influenza type A virus, Emmanuel et.al. (2006). The avian influenza virus belongs to ...

  5. New USDA licensed avian influenza vaccine (rHVT-AI) for protection against H5 avian influenza and usage discussion

    Science.gov (United States)

    Recently, a new avian influenza vaccine was licensed by USDA for use in the United States for protection of commercial poultry. The vaccine is a recombinant herpes virus of turkeys expressing the hemagglutinin gene of an H5 subtype avian influenza virus belonging to the 2.2 clade of the H5N1 highly ...

  6. [Epidemiological perspectives on SARS and avian influenza].

    Science.gov (United States)

    del Rey Calero, Juan

    2004-01-01

    SARS is a respiratory infection caused by Coronavirus (Nidoviruses, RNA) from which 3 groups are known. Group 1 affects dogs, cats, pigs, and the human agent is 229 E. Group 2 affects bovines or rodents, and the human agent is OC43. And group 3 corresponds to the avian pathology.... The epidemics emerged on February 2003 in Guangdong, South China, due to consumption of exotic animals (Civeta, etc.), and it spread through interperson contagion to other regions in Asia, America and Europe. Incubation period is about 2-7 days. Transmission Of the virus is person-to person, but also by excretions and residual water. Basic reproductive rate is 2 to 4, and it is considered that 2.7 persons are infected from the initial case. In June 2003, SARS affected over 8,000 people and 774 were killed. Mortality approaches to 10%, and it is higher among older people rising up to 50% in those aged over 65 years. It is important to quickly establish action protocols regarding clinical, epidemiological and prevention aspects. Avian influenza is an infection caused by type A Influenza Orthomixovirus, in which migration birds and wild ducks are the main reservoir. Avian viruses correspond to H5, H7, H9. In 1997 it was observed that type AH5N1 jumped interspecies barrier and affected 18 humans, and 6 of them died. At the end of 2003 and in 2004 this type of poultry flu was described in Asia. FAO has emphasized that sacrifice of chicken in affected farms is the most effective measure to fight against the disease. It has also been established suppression of imports from these countries. There is no evidence on interperson contagion from chicken contagion, nor on food-borne contagion to humans.

  7. The avian transcriptome response to malaria infection.

    Science.gov (United States)

    Videvall, Elin; Cornwallis, Charlie K; Palinauskas, Vaidas; Valkiūnas, Gediminas; Hellgren, Olof

    2015-05-01

    Malaria parasites are highly virulent pathogens which infect a wide range of vertebrates. Despite their importance, the way different hosts control and suppress malaria infections remains poorly understood. With recent developments in next-generation sequencing techniques, however, it is now possible to quantify the response of the entire transcriptome to infections. We experimentally infected Eurasian siskins (Carduelis spinus) with avian malaria parasites (Plasmodium ashfordi), and used high-throughput RNA-sequencing to measure the avian transcriptome in blood collected before infection (day 0), during peak parasitemia (day 21 postinfection), and when parasitemia was decreasing (day 31). We found considerable differences in the transcriptomes of infected and uninfected individuals, with a large number of genes differentially expressed during both peak and decreasing parasitemia stages. These genes were overrepresented among functions involved in the immune system, stress response, cell death regulation, metabolism, and telomerase activity. Comparative analyses of the differentially expressed genes in our study to those found in other hosts of malaria (human and mouse) revealed a set of genes that are potentially involved in highly conserved evolutionary responses to malaria infection. By using RNA-sequencing we gained a more complete view of the host response, and were able to pinpoint not only well-documented host genes but also unannotated genes with clear significance during infection, such as microRNAs. This study shows how the avian blood transcriptome shifts in response to malaria infection, and we believe that it will facilitate further research into the diversity of molecular mechanisms that hosts utilize to fight malaria infections. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  8. The threshold of a stochastic avian-human influenza epidemic model with psychological effect

    Science.gov (United States)

    Zhang, Fengrong; Zhang, Xinhong

    2018-02-01

    In this paper, a stochastic avian-human influenza epidemic model with psychological effect in human population and saturation effect within avian population is investigated. This model describes the transmission of avian influenza among avian population and human population in random environments. For stochastic avian-only system, persistence in the mean and extinction of the infected avian population are studied. For the avian-human influenza epidemic system, sufficient conditions for the existence of an ergodic stationary distribution are obtained. Furthermore, a threshold of this stochastic model which determines the outcome of the disease is obtained. Finally, numerical simulations are given to support the theoretical results.

  9. 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. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. USGS highly pathogenic avian influenza research strategy

    Science.gov (United States)

    Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

    2015-09-09

    Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

  11. Avian influenza overview September–November 2017

    DEFF Research Database (Denmark)

    Brown, Ian; Kuiken, Thijs; Mulatti, Paolo

    2017-01-01

    the outbreaks, no transmission to humans has been identified in the EU. The report includes an update of the list of wild bird target species for passive surveillance activities that is based on reported AI-infected wild birds since 2006. The purpose of this list is to provide information on which bird species...... the continuing threat of this avian influenza virus to human health and possible introduction via migratory wild birds into Europe. Close monitoring is required of the situation in Africa with regards to HPAI of the subtypes A(H5N1) and A(H5N8), given the rapidity of the evolution and the uncertainty...

  12. Parathyroid hormone binding to cultured avian osteoclasts

    Energy Technology Data Exchange (ETDEWEB)

    Teti, A.; Rizzoli, R.; Zambonin Zallone, A. (Univ. of Bari (Italy))

    1991-02-14

    Parathyroid hormone (PTH) increases serum calcium concentration via a controversial cellular mechanism. We investigated whether PTH binds avian osteoclasts. Isolated hypocalcaemic hen osteoclasts were incubated with ({sup 125}I)--bovine PTH (1-84). Specific binding of the hormone to the cells, which reached the equilibrium within 60 min, was observed. Half maximal binding was reached by 10 min. Binding was competitively inhibited by increasing doses of unlabeled PTH, and was about 55% displaced by adding, at the equilibrium, 10(-6) M unlabeled PTH. Autoradiography demonstrated specific label on the osteoclast. The cellular mechanism activated by the hormone remains to be elucidated.

  13. Tissue interactions of avian viral attachment proteins

    OpenAIRE

    Ambepitiya Wickramasinghe, I.N.

    2015-01-01

    Viruses can infect a wide range of hosts; varying from bacteria and plants to animals and humans. While many viral infections may pass unnoticed, some are of major importance due to their implications on health and welfare of plants, animals and/or humans. In particular, viruses that can infect avian hosts have been studied intensively due the occurrence of the pandemics of highly pathogenic influenza A virus infection or “bird flu’’. Viral infections in domesticated birds can result in huge ...

  14. 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 ...

  15. In vitro antiviral activity of chestnut and quebracho woods extracts against avian reovirus and metapneumovirus.

    Science.gov (United States)

    Lupini, C; Cecchinato, M; Scagliarini, A; Graziani, R; Catelli, E

    2009-12-01

    Field evidences have suggested that a natural extract, containing tannins, could be effective against poultry enteric viral infections. Moreover previous studies have shown that vegetable tannins can have antiviral activity against human viruses. Based on this knowledge three different Chestnut (Castanea spp.) wood extracts and one Quebracho (Schinopsis spp.) wood extract, all containing tannins and currently used in the animal feed industry, were tested for in vitro antiviral activity against avian reovirus (ARV) and avian metapneumovirus (AMPV). The MTT assay was used to evaluate the 50% cytotoxic compounds concentration (CC(50)) on Vero cells. The antiviral properties were tested before and after the adsorption of the viruses to Vero cells. Antiviral activities were expressed as IC(50) (concentration required to inhibit 50% of viral cytopathic effect). CC(50)s of tested compounds were > 200 microg/ml. All compounds had an extracellular antiviral effect against both ARV and AMPV with IC(50) values ranging from 25 to 66 microg/ml. Quebracho extract had also evident intracellular anti-ARV activity (IC(50) 24 microg/ml). These preliminary results suggest that the examined vegetable extracts might be good candidates in the control of some avian virus infections. Nevertheless further in vivo experiments are required to confirm these findings.

  16. 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.

  17. Contribution of Avian Salmonella enterica Isolates to Human Salmonellosis Cases in Constantine (Algeria

    Directory of Open Access Journals (Sweden)

    Rachid Elgroud

    2015-01-01

    Full Text Available An epidemiological investigation was carried out on one hundred Salmonella isolates from broiler farms, slaughterhouses, and human patients in the Constantine region of Algeria, in order to explore the contribution of avian strains to human salmonellosis cases in this region over the same period of time. The isolates were characterized by phenotypic as well as genotypic methods. A large variety of antimicrobial resistance profiles was found among human isolates, while only seven profiles were found among avian isolates. Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR, Insertion Sequence 200-PCR (IS200-PCR, and Pulsed Field Gel Electrophoresis (PFGE resulted in the allocation of the isolates to 16, 20, and 34 different profiles, respectively. The 3 genotyping methods led to complementary results by underlining the clonality of some serovars with the diffusion and persistence of a single clone in the Constantine area as well as stressing the polymorphism present in isolates belonging to other serovars, indicating the diversity of potential reservoirs of nontyphoidal Salmonella. Altogether, our results seem to indicate that nontyphoidal avian Salmonella may play an important role in human salmonellosis in the Constantine region.

  18. Avian personalities: characterization and epigenesis.

    Science.gov (United States)

    Groothuis, Ton G G; Carere, Claudio

    2005-02-01

    The work presented here aims at understanding the nature, epigenesis and function of personality types (here called behavioral profiles) in birds, focusing on a wild bird species, the great tit (Parus major). Lines bidirectionally selected for exploration show a wide array of social and non-social behavioral differences, and also some differences in physiological parameters. Line differences in these characteristics and their relationships show significant temporal consistency. The results show a surprising similarity between the great tit and a rodent model, suggesting a fundamental principle in the organization of behavioral profiles. The nature of this principle and whether or not it is multi-dimensional is discussed. However, the similarity with a chicken model is less clear, which points to some caution for generalization. The epigenesis of great tit behavioral profiles is discussed. Selection experiments with replication and backcrosses reveal a strong genetic basis, and suggest an influence of maternal effects. Ontogenetic manipulations indicate strong developmental plasticity, suggesting adaptive adjustment to prevailing environmental circumstances. They also show that behavioral characteristics belonging to the same profile can become uncoupled. Finally, field data on several fitness parameters of the different personalities in wild great tits are summarized. These data suggest that variation in selection pressure in time and space and assortative mating are plausible mechanisms accounting for the maintenance of different behavioral profiles within the same population.

  19. Avian-like breathing mechanics in maniraptoran dinosaurs.

    Science.gov (United States)

    Codd, Jonathan R; Manning, Phillip L; Norell, Mark A; Perry, Steven F

    2008-01-22

    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 theropod dinosaurs, prior to the evolution of flight. Here we report a phylogenetic analysis of the presence of uncinate processes in Aves and non-avian maniraptoran dinosaurs indicating that these were homologous structures. Furthermore, recent work on Canada geese has demonstrated that uncinate processes are integral to the mechanics of avian ventilation, facilitating both inspiration and expiration. In extant birds, uncinate processes function to increase the mechanical advantage for movements of the ribs and sternum during respiration. Our study presents a mechanism whereby uncinate processes, in conjunction with lateral and ventral movements of the sternum and gastral basket, affected avian-like breathing mechanics in extinct non-avian maniraptoran dinosaurs.

  20. 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

    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.

  1. Developmental studies of avian brain organization.

    Science.gov (United States)

    Puelles, Luis

    2018-01-01

    Avian brain organization or brain Bauplan is identical with that of vertebrates in general. This essay visits avian studies that contained advances or discussions about brain organization, trying to explain critically what they contributed. In order to start from a specific background, the new prevailing paradigm as regards brain organization, the prosomeric model, is presented first. Next a brief historic survey is made of how ideas on this topic evolved from the start of modern neuromorphology at the end of the 19th century. Longitudinal zonal organization with or without transverse segmentation (neuromeres) was the first overall concept applied to the brain. The idea of neuromeric structure later decayed in favour of a columnar model. This emphasized functional correlations rather than causal developmental content, assimilating forebrain functions to hindbrain ones. Though it became prevalent in the post-world-war period of neuroscience, in the last decades of the 20th century advances in molecular biology allowed developmental genes to be mapped, and it became evident that gene expression patterns support the old neuromeric model rather than the columnar one. This was also corroborated by modern experimental approaches (fate-mapping and analysis of patterning).

  2. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. PATHOMORPHOLOGICAL AND HISTOPATHOLOGICAL CHANGES OF AVIAN CHLAMYDIOSIS

    Directory of Open Access Journals (Sweden)

    Edin Šatrović

    2013-01-01

    Full Text Available Avian chlamydiosis is an infectious disease of birds caused by gram-negative bacterium Chlamydophila psittaci. However, this disease can occure among other mammals including humans. Chlamydiosis often presents as an inapparent infection, especially in older birds. During stressful conditions (deficient diet, transportation, great population density in small spaces, etc. and comorbidity, however, the birds usually begin to either present with the clinical signs of chlamydiosis, or secrete many causative agents to the environment. Depending on the serotype of the causative agent, and the type and age of the host, the disease usually causes systemic disorders, and is often fatal. The affected birds present with lethargy, fever, typical yellow-green discharge from the eyes and nose, diarrhea, anorexia and the weight lost. Bearing capacity is reduced. Autopsy findings show hepatomegaly with necrotic foci, splenomegaly and fibrinous inflammation of the pericardium, peritoneum and air sacs. Pathohistological findings reveal elementary bodies in the intercellular space dyed red to reddish purple using the Gimenez technique.Key words: avian chlamydiosis, pathomorphological changes, histopathological changes

  4. 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. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Milestones in avian coccidiosis research: a review.

    Science.gov (United States)

    Chapman, H D

    2014-03-01

    This article describes some of the milestones in research concerned with protozoan parasites of the genus Eimeria that infect birds and cause the disease coccidiosis. The time period covered is from 1891, when oocysts were first found in the ceca of diseased chickens, to the present. Progress in our understanding has lagged behind that of other protozoan parasites such as Toxoplasma and Plasmodium despite the enormous importance of Eimeria to animal livestock production. Nevertheless, applied research by universities, government agencies, and private industry has resulted in the successful development of methods of control, research that continues today. The topics covered and the references provided are selective and include life cycles and biology, pathology, ultrastructure, biochemistry, immunity, genetics, host cell invasion, species identification, taxonomy, chemotherapy, vaccination, and literature concerned with avian coccidiosis. This review is primarily concerned with the avian species of Eimeria that infect poultry, but some important advances, principally in immunology, have been made using species that infect rodents and rabbits. These are included where appropriate.

  6. 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...

  7. Data base on avian mortality on man-made structures

    Energy Technology Data Exchange (ETDEWEB)

    Dailey, N. S.

    1978-01-01

    A computerized data base concerning avian mortality on man-made structures is available for searching at the Ecological Sciences Information Center of the Information Center Complex, Information Division, Oak Ridge National Laboratory. This data base, which contains entries from the available literature, provides information on avian mortality from either collision into or electrocution on man-made structures. Primary emphasis has been placed on avian collision with obstacles such as television and radio towers, airport ceilometers, transmission lines, and cooling towers. Other structures included in the studies are fences, glass walls and windows, lighthouses, telegraph and telephone wires, buildings, monuments, smokestacks, and water towers.

  8. Stopover ecology of Black-tailed Godwits Limosa limosa limosa in Portuguese rice fields : a guide on where to feed in winter

    NARCIS (Netherlands)

    Lourenco, Pedro M.; Piersma, Theunis

    Capsule Conservation management of rice fields may be necessary to guarantee the availability of high quality stopover habitats. Aims To analyse habitat selection and quantify the diet composition of birds. Methods Using water level and agricultural management of the fields as variables, habitat

  9. 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.

  10. Detection of H5 and H7 highly pathogenic avian influenza virus with lateral flow devices: performance with healthy, sick and dead chickens

    Science.gov (United States)

    Rapid detection of highly pathogenic avian influenza virus (HPAIV) in the field is critical for effective disease control and to differentiate it from other diseases, such as Newcastle disease. Lateral flow devices (LFD) are commercially available and provide a fast, highly specific, on-site test fo...

  11. Guide device

    International Nuclear Information System (INIS)

    Brammer, C.M. Jr.

    1977-01-01

    Disclosed is a fuel handling guide tube centering device for use in nuclear reactors during fuel assembly handling operations. The device comprises an outer ring secured to the flange of a nuclear reactor pressure vessel, a rotatable table rotatably coupled to the outer ring, and a plurality of openings through the table. Truncated locating cones are positioned in each of the openings in the table, and the locating cones center the guide tube during fuel handling operations. The openings in the table are located such that each fuel assembly in the nuclear core may be aligned with one of the openings by a suitable rotation of the table. The locating cones thereby provide alignment between the fuel handling mechanism located in the guide tube and the individual fuel assemblies of the cone. The need for a device to provide alignment is especially critical for floating nuclear power plants, where wave motion may exist during fuel handling operations. 5 claims, 4 figures

  12. Avian Models for Human Cognitive Neuroscience: A Proposal.

    Science.gov (United States)

    Clayton, Nicola S; Emery, Nathan J

    2015-06-17

    Research on avian cognitive neuroscience over the past two decades has revealed the avian brain to be a better model for understanding human cognition than previously thought, despite differences in the neuroarchitecture of avian and mammalian brains. The brain, behavior, and cognition of songbirds have provided an excellent model of human cognition in one domain, namely learning human language and the production of speech. There are other important behavioral candidates of avian cognition, however, notably the capacity of corvids to remember the past and plan for the future, as well as their ability to think about another's perspective, and physical reasoning. We review this work and assess the evidence that the corvid brain can support such a cognitive architecture. We propose potential applications of these behavioral paradigms for cognitive neuroscience, including recent work on single-cell recordings and neuroimaging in corvids. Finally, we discuss their impact on understanding human developmental cognition. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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...... the outbreak strain. Among 68 isolates from wild birds, only one PFGE and one REA pattern were demonstrated, whereas among 23 isolates from domestic poultry, 14 different SmaI, 12 different ApaI, and 10 different HpaII patterns were found. The results suggest that a P. multocida strain has survived during...

  14. Avian use of proposed KENETECH and CARES wind farm sites in Klickitat County, Washington. Appendix C to Washington Windplant No. 1 EIS. Technical report

    International Nuclear Information System (INIS)

    1995-01-01

    The Columbia Hills area above (north of) the Columbia River in Klickitat County, in southcentral Washington, is being considered for development of two wind power generation projects that could include the eventual placement of up to 436 wind turbines. The KENETECH Windpower Washington Windplant TM Number 1 project would include placing up to 345 KENETECH 33M-VS turbines, capable of producing up to 115 megawatts (MW), in 39 rows (strings) on a 5,110-hectare (12,630-acre) site. During scoping for these proposed developments, concerns were raised regarding the potential for avian mortality associated with wind farm development. Collision with wind turbine blade, towers, guy wires, and transmission lines, and electrocution from power lines have been identified as sources of avian mortality, particularly raptors, at existing wind farm facilities. To address these concerns, an avian study was conducted at the site in accordance with an avian study plan and protocol developed, with input from a national avian task force, state agencies (Washington Department of Fish and Wildlife [WDFW]), and federal agencies (USFWS). The study included four elements: (1) a winter raptor and waterfowl study, (2) spring migration and fall migration studies, (3) a summer resident study, and (4) a raptor breeding study. The study involved extensive field studies conducted by biologists experienced in identifying raptors and other birds

  15. 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].

  16. Resistance gene transfer during treatments for experimental avian colibacillosis.

    Science.gov (United States)

    Dheilly, Alexandra; Le Devendec, Laëtitia; Mourand, Gwenaëlle; Bouder, Axelle; Jouy, Eric; Kempf, Isabelle

    2012-01-01

    An experiment was conducted in animal facilities to compare the impacts of four avian colibacillosis treatments-oxytetracycline (OTC), trimethoprim-sulfadimethoxine (SXT), amoxicillin (AMX), or enrofloxacin (ENR)-on the susceptibility of Escherichia coli in broiler intestinal tracts. Birds were first orally inoculated with rifampin-resistant E. coli strains bearing plasmid genes conferring resistance to fluoroquinolones (qnr), cephalosporins (bla(CTX-M) or bla(FOX)), trimethoprim-sulfonamides, aminoglycosides, or tetracyclines. Feces samples were collected before, during, and after antimicrobial treatments. The susceptibilities of E. coli strains were studied, and resistance gene transfer was analyzed. An increase in the tetracycline-resistant E. coli population was observed only in OTC-treated birds, whereas multiresistant E. coli was detected in the dominant E. coli populations of SXT-, AMX-, or ENR-treated birds. Most multiresistant E. coli strains were susceptible to rifampin and exhibited various pulsed-field gel electrophoresis profiles, suggesting the transfer of one of the multiresistance plasmids from the inoculated strains to other E. coli strains in the intestinal tract. In conclusion, this study clearly illustrates how, in E. coli, "old" antimicrobials may coselect antimicrobial resistance to recent and critical molecules.

  17. 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.

  18. Avian Influenza spread and transmission dynamics

    Science.gov (United States)

    Bourouiba, Lydia; Gourley, Stephen A.; Liu, Rongsong; Takekawa, John Y.; Wu, Jianhong; Chen, Dongmei; Moulin, Bernard; Wu, Jianhong

    2015-01-01

    The spread of highly pathogenic avian influenza (HPAI) viruses of type A of subtype H5N1 has been a serious threat to global public health. Understanding the roles of various (migratory, wild, poultry) bird species in the transmission of these viruses is critical for designing and implementing effective control and intervention measures. Developing appropriate models and mathematical techniques to understand these roles and to evaluate the effectiveness of mitigation strategies have been a challenge. Recent development of the global health surveillance (especially satellite tracking and GIS techniques) and the mathematical theory of dynamical systems combined have gradually shown the promise of some cutting-edge methodologies and techniques in mathematical biology to meet this challenge.

  19. Mechanisms of avian songs and calls

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye

    2008-01-01

    . It consists of a skeletal framework, flexible membranes or soft tissue masses, labia, stretched between elements of this framework, and the syringeal muscles. Until a decade ago most of our knowledge about syringeal mechanics was based on such indirect evidence as electromyography, emitted sound, and anatomy....... The use of thin, flexible endoscopes has made direct observation of the syrinx possible in situ. The effects of direct muscle stimulation on the syringeal aperture have identified adductor and abductor muscles, confirming results from electromyographic studies. Endoscopic observations have revealed......-filming during sound production has revealed that sound pulses coincide with short duration formation of slots between the soft tissue masses forming a pneumatic valve, which suggests that the avian sound generating mechanism is a similar to that in the human larynx. Lately studies have revealed surprising...

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

    OpenAIRE

    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 (chicken, ducklings) the ontogeny of some important neural structures are described. In the early post hatching phase, peripheral and deep-body thermoreceptors are present and functional, even in altr...

  1. Will Wallace's Line Save Australia from Avian Influenza?

    Directory of Open Access Journals (Sweden)

    Hamish I. McCallum

    2008-12-01

    Full Text Available Australia is separated from the Asian faunal realm by Wallace's Line, across which there is relatively little avian migration. Although this does diminish the risk of high pathogenicity avian influenza of Asian origin arriving with migratory birds, the barrier is not complete. Migratory shorebirds, as well as a few landbirds, move through the region on annual migrations to and from Southeast Asia and destinations further north, although the frequency of infection of avian influenza in these groups is low. Nonetheless, high pathogenicity H5N1 has recently been recorded on the island of New Guinea in West Papua in domestic poultry. This event increases interest in the movements of birds between Wallacea in eastern Indonesia, New Guinea, and Australia, particularly by waterbirds. There are frequent but irregular movements of ducks, geese, and other waterbirds across Torres Strait between New Guinea and Australia, including movements to regions in which H5N1 has occurred in the recent past. Although the likelihood of avian influenza entering Australia via an avian vector is presumed to be low, the nature and extent of bird movements in this region is poorly known. There have been five recorded outbreaks of high pathogenicity avian influenza in Australian poultry flocks, all of the H7 subtype. To date, Australia is the only inhabited continent not to have recorded high pathogenicity avian influenza since 1997, and H5N1 has never been recorded. The ability to map risk from high pathogenicity avian influenza to Australia is hampered by the lack of quantitative data on the extent of bird movements between Australia and its northern neighbors. Recently developed techniques offer the promise to fill this knowledge gap.

  2. Spleen necrosis virus, an avian retrovirus, can infect primate cells.

    OpenAIRE

    Koo, H M; Brown, A M; Ron, Y; Dougherty, J P

    1991-01-01

    Spleen necrosis virus (SNV) is an avian retrovirus that can infect some mammalian cells such as dog cells as well as all avian cells tested to date. We were interested in testing whether SNV could also infect primate cells. For these experiments, we used HeLa and COS-7 cells. Initially, we determined whether the SNV long terminal repeat promoter was functional in HeLa and COS-7 cells. In transient transfection assays, the SNV promoter efficiently directed chloramphenicol acetyltransferase gen...

  3. MRI-guided periradicular nerve root infiltration therapy in low-field (0.23-T) MRI system using optical instrument tracking

    International Nuclear Information System (INIS)

    Sequeiros, Roberto Blanco; Ojala, Risto O.; Klemola, Rauli; Jyrkinen, Lasse; Tervonen, Osmo A.; Vaara, Teuvo J.

    2002-01-01

    The purpose of this study was to evaluate the feasibility of the MRI-guided periradicular nerve root infiltration therapy. Sixty-seven nerve root infiltrations under MRI guidance were done for 61 patients suffering from lumbosacral radicular pain. Informed consent was acquired from all patients. A 0.23-T open-MRI scanner with interventional tools (Outlook Proview, Philips Medical Systems, MR Technologies, Finland) was used. A surface coil was used in all cases. Nerve root infiltration was performed with MRI-compatible 20-G needle (Chiba type MReye, Cook, Bloomington, Ind.; or Manan type, MD Tech, Florida). The evaluation of clinical outcome was achieved with 6 months of clinical follow-up and questionnaire. The effect of nerve root infiltration to the radicular pain was graded: 1=good to excellent, i.e., no pain or not disturbing pain allowing normal physical activity at 3 months from the procedure; 2=temporary, i.e., temporary relief of pain; 3=no relief of pain; and 4=worsening of pain. As an adjunct to MRI-guided positioning of the needle the correct needle localization by the nerve root was confirmed with saline injection to nerve root channel and single-shot fast spin echo (SSFSE) imaging. The MRI guidance allowed adequate needle positioning in all but 1 case (98.5%). This failure was caused by degeneration-induced changes in anatomy. Of patients, 51.5% had good to excellent effect with regard to radicular pain from the procedure, 22.7% had temporary relief, 21.2% had no effect, and in 4.5% the pain worsened. Our results show that MRI guidance is accurate and safe in performing nerve root infiltration at lumbosacral area. The results of radicular pain relief from nerve root infiltration are comparable to CT or fluoroscopy studies on the subject. (orig.)

  4. Impacts of climate change on avian populations.

    Science.gov (United States)

    Jenouvrier, Stephanie

    2013-07-01

    This review focuses on the impacts of climate change on population dynamics. I introduce the MUP (Measuring, Understanding, and Predicting) approach, which provides a general framework where an enhanced understanding of climate-population processes, along with improved long-term data, are merged into coherent projections of future population responses to climate change. This approach can be applied to any species, but this review illustrates its benefit using birds as examples. Birds are one of the best-studied groups and a large number of studies have detected climate impacts on vital rates (i.e., life history traits, such as survival, maturation, or breeding, affecting changes in population size and composition) and population abundance. These studies reveal multifaceted effects of climate with direct, indirect, time-lagged, and nonlinear effects. However, few studies integrate these effects into a climate-dependent population model to understand the respective role of climate variables and their components (mean state, variability, extreme) on population dynamics. To quantify how populations cope with climate change impacts, I introduce a new universal variable: the 'population robustness to climate change.' The comparison of such robustness, along with prospective and retrospective analysis may help to identify the major climate threats and characteristics of threatened avian species. Finally, studies projecting avian population responses to future climate change predicted by IPCC-class climate models are rare. Population projections hinge on selecting a multiclimate model ensemble at the appropriate temporal and spatial scales and integrating both radiative forcing and internal variability in climate with fully specified uncertainties in both demographic and climate processes. © 2013 Blackwell Publishing Ltd.

  5. Ultrasonic guided waves in bone.

    Science.gov (United States)

    Moilanen, Petro

    2008-01-01

    Recent progress in quantitative ultrasound (QUS) has shown increasing interest toward measuring long bones by ultrasonic guided waves. This technology is widely used in the field of nondestructive testing and evaluation of different waveguide structures. Cortical bone provides such an elastic waveguide and its ability to sustain loading and resist fractures is known to be related to its mechanical properties at different length scales. Because guided waves could yield diverse characterizations of the bone's mechanical properties at the macroscopic level, the method of guided waves has a strong potential over the standardized bone densitometry as a tool for bone assessment. Despite this, development of guided wave methods is challenging, e.g., due to interferences and multiparametric inversion problems. This paper discusses the promises and challenges related to bone characterization by ultrasonic guided waves.

  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. 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.

  8. Localization of a sound source in in a guided medium and reverberating field. Contribution to a study on leak localization in the internal wall of containment of a nuclear reactor in the case of a severe reactor accident

    International Nuclear Information System (INIS)

    Thomann, F.

    1996-01-01

    Basic data necessary for the localization of a leak in the internal wall of the containment are presented by studying the sound generated by gas jets coming out of (leaking fissures) as well as propagation in a guided medium. The results acquired have led us to choose the simple intercorrelation method and the matched filed processing method, both of which are likely to adequately handle our problems. Whereas the intercorrelation method appears to be limited in scope when dealing in the guided medium, the matched field processing is suited to leak localization over a surface of approximately 1000 m 2 (for a total surface of 10 000 m 2 ). Preliminary studies on the leak signal and on replicated signals have led us to limit the frequency band to 2600 - 3000 Hz. We have succeeded in locating a leak situated in an ordinary position with a minimum amount of replicated signals and basic data. We have improved on the estimation of Bartlett and MVDE (minimum variance distortion less filter) rendering them even more effective. Afterwards, we considered the severe accident situation and showed that the system can be installed in situ. (author)

  9. Wiggler Effects on the Growth Rate of a Raman Free-electron Laser with Axial Magnetic Field or Ion-Channel Guiding

    CERN Document Server

    Maraghechi, Behrouz

    2004-01-01

    A relativistic theory for Raman backscattering in the beam frame of electrons is presented and is used to find the growth rate of a free-electron laser (FEL), in the Raman regime. A one dimensional helical wiggler and an axial magnetic field are considered. The effects of static self-electric and self-magnetic fields, induced by the steady-state charge density and currents of the non-neutral electron beam, are taken into account to find the steady-state trajectories. The wiggler effects on the linear dispersion relations of the space-charge wave and radiation are included in the analysis. A numerical computation is conducted to compare the growth rate of the excited waves with nonrelativistic treatment. It was found that self-field effects increase the growth rate in the group II orbits and decrease it in the group I orbits. However, the wiggler effects on growth rate are stronger and increase the growth rate on both group I and group II orbits. The discontinuity, due to the cyclotron resonance with the radia...

  10. Avian vocal mimicry: a unified conceptual framework.

    Science.gov (United States)

    Dalziell, Anastasia H; Welbergen, Justin A; Igic, Branislav; Magrath, Robert D

    2015-05-01

    Mimicry is a classical example of adaptive signal design. Here, we review the current state of research into vocal mimicry in birds. Avian vocal mimicry is a conspicuous and often spectacular form of animal communication, occurring in many distantly related species. However, the proximate and ultimate causes of vocal mimicry are poorly understood. In the first part of this review, we argue that progress has been impeded by conceptual confusion over what constitutes vocal mimicry. We propose a modified version of Vane-Wright's (1980) widely used definition of mimicry. According to our definition, a vocalisation is mimetic if the behaviour of the receiver changes after perceiving the acoustic resemblance between the mimic and the model, and the behavioural change confers a selective advantage on the mimic. Mimicry is therefore specifically a functional concept where the resemblance between heterospecific sounds is a target of selection. It is distinct from other forms of vocal resemblance including those that are the result of chance or common ancestry, and those that have emerged as a by-product of other processes such as ecological convergence and selection for large song-type repertoires. Thus, our definition provides a general and functionally coherent framework for determining what constitutes vocal mimicry, and takes account of the diversity of vocalisations that incorporate heterospecific sounds. In the second part we assess and revise hypotheses for the evolution of avian vocal mimicry in the light of our new definition. Most of the current evidence is anecdotal, but the diverse contexts and acoustic structures of putative vocal mimicry suggest that mimicry has multiple functions across and within species. There is strong experimental evidence that vocal mimicry can be deceptive, and can facilitate parasitic interactions. There is also increasing support for the use of vocal mimicry in predator defence, although the mechanisms are unclear. Less progress has

  11. 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.

  12. Antimicrobial Products Registered for Disinfection Use against Avian Influenza on Poultry Farms and Other Facilities

    Science.gov (United States)

    EPA registers disinfectants against Avian Influenza A. Although there are no antimicrobial products registered for the H5N2 subtype of Avian Influenza A virus, based on available scientific information these products will work against other HPAI strains.

  13. Field-trip guide for exploring pyroclastic density current deposits from the May 18, 1980, eruption of Mount St. Helens, Washington

    Science.gov (United States)

    Brand, Brittany D.; Pollock, Nicholas; Sarocchi, Damiano; Dufek, Josef; Clynne, Michael A.

    2017-07-05

    Pyroclastic density currents (PDCs) are one of the most dangerous phenomena associated with explosive volcanism. To help constrain damage potential, a combination of field studies, laboratory experiments, and numerical modeling are used to establish conditions that influence PDC dynamics and depositional processes, including runout distance. The objective of this field trip is to explore field relations that may constrain PDCs at the time of emplacement.The PDC deposits from the May 18, 1980, eruption of Mount St. Helens are well exposed along the steep flanks (10–30° slopes) and across the pumice plain (5–12° slopes) as far as 8 km north of the volcano. The pumice plain deposits represent deposition from a series of concentrated PDCs and are primarily thick (3–12 m), massive, and poorly sorted. In contrast, the steep east-flank deposits are stratified to cross-stratified, suggesting deposition from PDCs where turbulence strongly influenced transport and depositional processes.The PDCs that descended the west flank were largely nondepositional; they maintained a higher flow energy and carrying capacity than PDCs funneled through the main breach, as evidenced by the higher concentration of large blocks in their deposits. The PDC from the west flank collided with PDCs funneled through the breach at various points along the pumice plain. Evidence for flow collision will be explored and debated throughout the field trip.Evidence for substrate erosion and entrainment is found (1) along the steep eastern flank of the volcano, which has a higher degree of rough, irregular topography relative to the west flanks where PDCs were likely nonerosive, (2) where PDCs encountered debris-avalanche hummocks across the pumice plain, and (3) where PDCs eroded and entrained material deposited by PDCs produced during earlier phases of the eruption. Two features interpreted as large-scale (tens of meters wide) levees and a large (~200 m wide) channel scour-and-fill feature

  14. Avian predation on juvenile salmonids in the Lower Columbia River; 1998 annual report

    International Nuclear Information System (INIS)

    Collis, Ken; Adamany, Stephanie; Roby, Daniel D.; Craig, David P.; Lyons, Donald E.

    2000-01-01

    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

  15. 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.

  16. Field Campaign Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Voyles, J. W. [DOE ARM Climate Research Facility, Washington, DC (United States); Chapman, L. A. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-12-01

    This document establishes a common set of guidelines for the Atmospheric Radiation Measurement (ARM) Climate Research Facility for planning, executing, and closing out field campaigns. The steps that guide individual field campaigns are described in the Field Campaign Tracking System and are specifically tailored to meet the scope of each field campaign.

  17. Volumetric-modulated arc therapy (RapidArc) vs. conventional fixed-field intensity-modulated radiotherapy for {sup 18}F-FDG-PET-guided dose escalation in oropharyngeal cancer: A planning study

    Energy Technology Data Exchange (ETDEWEB)

    Teoh, May, E-mail: m.teoh@nhs.net [Department of Oncology, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Beveridge, Sabeena [Department of Medical Physics, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Wood, Katie; Whitaker, Stephen [Department of Oncology, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Adams, Elizabeth; Rickard, Donna; Jordan, Tom; Nisbet, Andrew [Department of Medical Physics, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); Clark, Catharine H. [Department of Medical Physics, St. Luke' s Cancer Centre, Royal Surrey County Hospital, Guildford, Surrey (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex (United Kingdom)

    2013-04-01

    Fluorine-18-fluorodeoxyglucose-positron emission tomography ({sup 18}F-FDG-PET)–guided focal dose escalation in oropharyngeal cancer may potentially improve local control. We evaluated the feasibility of this approach using volumetric-modulated arc therapy (RapidArc) and compared these plans with fixed-field intensity-modulated radiotherapy (IMRT) focal dose escalation plans. Materials and methods: An initial study of 20 patients compared RapidArc with fixed-field IMRT using standard dose prescriptions. From this cohort, 10 were included in a dose escalation planning study. Dose escalation was applied to {sup 18}F-FDG-PET–positive regions in the primary tumor at dose levels of 5% (DL1), 10% (DL2), and 15% (DL3) above standard radical dose (65 Gy in 30 fractions). Fixed-field IMRT and double-arc RapidArc plans were generated for each dataset. Dose-volume histograms were used for plan evaluation and comparison. The Paddick conformity index (CI{sub Paddick}) and monitor units (MU) for each plan were recorded and compared. Both IMRT and RapidArc produced clinically acceptable plans and achieved planning objectives for target volumes. Dose conformity was significantly better in the RapidArc plans, with lower CI{sub Paddick} scores in both primary (PTV1) and elective (PTV2) planning target volumes (largest difference in PTV1 at DL3; 0.81 ± 0.03 [RapidArc] vs. 0.77 ± 0.07 [IMRT], p = 0.04). Maximum dose constraints for spinal cord and brainstem were not exceeded in both RapidArc and IMRT plans, but mean doses were higher with RapidArc (by 2.7 ± 1 Gy for spinal cord and 1.9 ± 1 Gy for brainstem). Contralateral parotid mean dose was lower with RapidArc, which was statistically significant at DL1 (29.0 vs. 29.9 Gy, p = 0.01) and DL2 (29.3 vs. 30.3 Gy, p = 0.03). MU were reduced by 39.8–49.2% with RapidArc (largest difference at DL3, 641 ± 94 vs. 1261 ± 118, p < 0.01). {sup 18}F-FDG-PET–guided focal dose escalation in oropharyngeal cancer is feasible with Rapid

  18. Field-trip guide to mafic volcanism of the Cascade Range in Central Oregon—A volcanic, tectonic, hydrologic, and geomorphic journey

    Science.gov (United States)

    Deligne, Natalia I.; Mckay, Daniele; Conrey, Richard M.; Grant, Gordon E.; Johnson, Emily R.; O'Connor, Jim; Sweeney, Kristin

    2017-08-16

    The Cascade Range in central Oregon has been shaped by tectonics, volcanism, and hydrology, as well as geomorphic forces that include glaciations. As a result of the rich interplay between these forces, mafic volcanism here can have surprising manifestations, which include relatively large tephra footprints and extensive lava flows, as well as water shortages, transportation and agricultural disruption, and forest fires. Although the focus of this multidisciplinary field trip will be on mafic volcanism, we will also look at the hydrology, geomorphology, and ecology of the area, and we will examine how these elements both influence and are influenced by mafic volcanism. We will see mafic volcanic rocks at the Sand Mountain volcanic field and in the Santiam Pass area, at McKenzie Pass, and in the southern Bend region. In addition, this field trip will occur during a total solar eclipse, the first one visible in the United States in more than 25 years (and the first seen in the conterminous United States in more than 37 years).The Cascade Range is the result of subduction of the Juan de Fuca plate underneath the North American plate. This north-south-trending volcanic mountain range is immediately downwind of the Pacific Ocean, a huge source of moisture. As moisture is blown eastward from the Pacific on prevailing winds, it encounters the Cascade Range in Oregon, and the resulting orographic lift and corresponding rain shadow is one of the strongest precipitation gradients in the conterminous United States. We will see how the products of the volcanoes in the central Oregon Cascades have had a profound influence on groundwater flow and, thus, on the distribution of Pacific moisture. We will also see the influence that mafic volcanism has had on landscape evolution, vegetation development, and general hydrology.

  19. Multi-gradient echo MR thermometry for monitoring of the near-field area during MR-guided high intensity focused ultrasound heating.

    Science.gov (United States)

    Lam, Mie K; de Greef, Martijn; Bouwman, Job G; Moonen, Chrit T W; Viergever, Max A; Bartels, Lambertus W

    2015-10-07

    The multi-gradient echo MR thermometry (MGE MRT) method is proposed to use at the interface of the muscle and fat layers found in the abdominal wall, to monitor MR-HIFU heating. As MGE MRT uses fat as a reference, it is field-drift corrected. Relative temperature maps were reconstructed by subtracting absolute temperature maps. Because the absolute temperature maps are reconstructed of individual scans, MGE MRT provides the flexibility of interleaved mapping of temperature changes between two arbitrary time points. The method's performance was assessed in an ex vivo water bath experiment. An ex vivo HIFU experiment was performed to show the method's ability to monitor heating of consecutive HIFU sonications and to estimate cooling time constants, in the presence of field drift. The interleaved use between scans of a clinical protocol was demonstrated in vivo in a patient during a clinical uterine fibroid treatment. The relative temperature measurements were accurate (mean absolute error 0.3 °C) and provided excellent visualization of the heating of consecutive HIFU sonications. Maps were reconstructed of estimated cooling time constants and mean ROI values could be well explained by the applied heating pattern. Heating upon HIFU sonication and subsequent cooling could be observed in the in vivo demonstration.

  20. Community response to avian flu in Central Java, Indonesia.

    Science.gov (United States)

    Padmawati, Siwi; Nichter, Mark

    2008-04-01

    This pilot study suggests that it is more appropriate to think of avian flu as a bio-social and bio-political challenge for Indonesia than merely an epidemiological challenge involving a disease of zoonotic origin. Our examination of popular perceptions of avian flu in Central Java reveals important differences of opinion about which types of fowl are responsible for avian flu transmission and the degree of risk H5N1 poses to humans. The opinions of backyard farmers and commercial poultry farmers are motivated by different forms of practical logic and are differentially influenced by media accounts, government education programmes, foreign aid and rumours about who stands to profit from the disease. Rumours reflect collective anxieties about globalization, the agenda of big business and the trustworthiness of the national government. We also illustrate how a commodity chain analysis can assist in the identification of different stake-holders in the informal and formal poultry industries. The position of each stake-holder needs to be considered in any comprehensive investigation of avian flu. An economic analysis of the capital investment of stake-holders provides insight into how each responds to government directives about the reporting of dead chickens, vaccinating birds etc. Finally, we call for research on avian flu preparedness attentive to Indonesia's de-centralized form of political rule and the social organization of communities so that clear lines of communication and command can be established and mutual assistance mobilized.

  1. Persistence of Pasteurella multocida in wetlands following avian cholera outbreaks

    Science.gov (United States)

    Blanchong, Julie A.; Samuel, M.D.; Goldberg, Diana R.; Shadduck, D.J.; Lehr, M.A.

    2006-01-01

    Avian cholera, caused by Pasteurella multocida, affects waterbirds across North America and occurs worldwide among various avian species. Once an epizootic begins, contamination of the wetland environment likely facilitates the transmission of P. multocida to susceptible birds. To evaluate the ability of P. multocida serotype-1, the most common serotype associated with avian cholera in waterfowl in western and central North America, to persist in wetlands and to identify environmental factors associated with its persistence, we collected water and sediment samples from 23 wetlands during winters and springs of 1996a??99. These samples were collected during avian cholera outbreaks and for up to 13 wk following initial sampling. We recovered P. multocida from six wetlands that were sampled following the initial outbreaks, but no P. multocida was isolated later than 7 wk after the initial outbreak sampling. We found no significant relationship between the probability of recovery of P. multocida during resampling and the abundance of the bacterium recovered during initial sampling, the substrate from which isolates were collected, isolate virulence, or water quality conditions previously suggested to be related to the abundance or survival of P. multocida. Our results indicate that wetlands are unlikely to serve as a long-term reservoir for P. multocida because the bacterium does not persist in wetlands for long time periods following avian cholera outbreaks.

  2. 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.

  3. 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.

  4. An Outbreak Of Highly Pathogenic Avian Influenza (Hpai) In A Mixed ...

    African Journals Online (AJOL)

    An Outbreak Of Highly Pathogenic Avian Influenza (Hpai) In A Mixed Farm By The Introduction Of A Water Fowl. ... C A Meseko, A T Oladokun, B Shehu. Abstract. Avian influenza (AI) is caused by a range of Influenza type A viruses of high and low pathogenicity (Fauci, 2005). H5N1 Highly Pathogenic Avian Influenza (HPAI) ...

  5. The influence of vertical and horizontal habitat structure on nationwide patterns of avian biodiversity

    Science.gov (United States)

    Patrick D. Culbert; Volker C. Radeloff; Curtis H. Flather; Josef M. Kellndorfer; Chadwick D. Rittenhouse; Anna M. Pidgeon

    2013-01-01

    With limited resources for habitat conservation, the accurate identification of high-value avian habitat is crucial. Habitat structure affects avian biodiversity but is difficult to quantify over broad extents. Our goal was to identify which measures of vertical and horizontal habitat structure are most strongly related to patterns of avian biodiversity across the...

  6. 9 CFR 145.15 - Diagnostic surveillance program for low pathogenic avian influenza.

    Science.gov (United States)

    2010-01-01

    ... low pathogenic avian influenza. 145.15 Section 145.15 Animals and Animal Products ANIMAL AND PLANT... pathogenic avian influenza. (a) The Official State Agency must develop a diagnostic surveillance program for H5/H7 low pathogenic avian influenza for all poultry in the State. The exact provisions of the...

  7. Experimental induced avian E. coli salpingitis

    DEFF Research Database (Denmark)

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

    2016-01-01

    Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease manifesta......Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease...... 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......) had a distinct ability to cause disease. Results of the study shows major differences in virulence of different strains of E. coli in ascending infections; however, there was no indication of tissue-specific adaptation, since strains obtained from lesions unrelated to the reproductive system were...

  8. Comparison of lead residues among avian bones

    International Nuclear Information System (INIS)

    Ethier, A.L.M.; Braune, B.M.; Scheuhammer, A.M.; Bond, D.E.

    2007-01-01

    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

  9. Public health risk from avian influenza viruses.

    Science.gov (United States)

    Perdue, Michael L; Swayne, David E

    2005-09-01

    Since 1997, avian influenza (AI) virus infections in poultry have taken on new significance, with increasing numbers of cases involving bird-to-human transmission and the resulting production of clinically severe and fatal human infections. Such human infections have been sporadic and are caused by H7N7 and H5N1 high-pathogenicity (HP) and H9N2 low-pathogenicity (LP) AI viruses in Europe and Asia. These infections have raised the level of concern by human health agencies for the potential reassortment of influenza virus genes and generation of the next human pandemic influenza A virus. The presence of endemic infections by H5N1 HPAI viruses in poultry in several Asian countries indicates that these viruses will continue to contaminate the environment and be an exposure risk with human transmission and infection. Furthermore, the reports of mammalian infections with H5N1 AI viruses and, in particular, mammal-to-mammal transmission in humans and tigers are unprecedented. However, the subsequent risk for generating a pandemic human strain is unknown. More international funding from both human and animal health agencies for diagnosis or detection and control of AI in Asia is needed. Additional funding for research is needed to understand why and how these AI viruses infect humans and what pandemic risks they pose.

  10. Avian Metapneumovirus circulation in Italian broiler farms.

    Science.gov (United States)

    Tucciarone, Claudia Maria; Franzo, Giovanni; Lupini, Caterina; Alejo, Carolina Torres; Listorti, Valeria; Mescolini, Giulia; Brandão, Paulo Eduardo; Martini, Marco; Catelli, Elena; Cecchinato, Mattia

    2018-02-01

    With increasing frequency, avian Metapneumovirus (aMPV) is reported to induce respiratory signs in chickens. An adequate knowledge of current aMPV prevalence among Italian broilers is lacking, with little information available on its economical and health impact on the poultry industry. In order to collect preliminary data on the epidemiological context of aMPV in broiler flocks, a survey was performed in areas of Northern Italy with high poultry density from 2014 to 2016. Upper respiratory tract swabs were collected and processed by A and B subtype-specific multiplex real-time reverse transcription PCR (RT-PCR). Samples were also screened for infectious bronchitis virus (IBV) by generic RT-PCR and sequencing. Productive data and respiratory signs were detailed where possible. The high prevalence of aMPV was confirmed in broilers older than 26 d and also attested in IBV-negative farms. All aMPV detections belonged to subtype B. Italian strain genetic variability was evaluated by the partial attachment (G) gene sequencing of selected strains and compared with contemporary turkey strains and previously published aMPV references, revealing no host specificity and the progressive evolution of this virus in Italy. © 2017 Poultry Science Association Inc.

  11. 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.

  12. Review of Avian Influenza Outbreaks in South Korea from 1996 to 2014.

    Science.gov (United States)

    Mo, In-Pil; Bae, Yeon-Ji; Lee, Seung-Baek; Mo, Jong-Suk; Oh, Kwang-Hyun; Shin, Jeong-Hwa; Kang, Hyun-Mi; Lee, Youn-Jeong

    2016-05-01

    Since the first outbreak of low pathogenic avian influenza (LPAI) in 1996, outbreaks of LPAI have become more common in Korea, leading to the development of a nationwide mass vaccination program in 2007. In the case of highly pathogenic avian influenza (HPAI), four outbreaks took place in 2003-04, 2006-07, 2008, and 2010-11; a fifth outbreak began in 2014 and was ongoing at the time of this writing. The length of the four previous outbreaks varied, ranging from 42 days (2008) to 139 days (2010-11). The number of cases reported by farmers that were subsequently confirmed as HPAI also varied, from seven cases in 2006-07 to 53 in 2010-11. The number of farms affected by the outbreaks varied, from a low of 286 (2006-07) with depopulation of 6,473,000 birds, to a high of 1500 farms (2008) with depopulation of 10,200,000 birds. Government compensation for bird depopulation ranged from $253 million to $683 million in the five outbreaks. Despite the damage caused by the five HPAI outbreaks, efficient control strategies have yet to be established. Meanwhile, the situation in the field worsens. Analysis of the five HPAI outbreaks revealed horizontal farm-to-farm transmission as the main factor effecting major economic losses. However, horizontal transmission could not be efficiently prevented because of insufficient transparency within the poultry industry, especially within the duck industry, which is reluctant to report suspicious cases early. Moreover, the experiences and expertise garnered in previous outbreaks has yet to be effectively applied to the management of new outbreaks. Considering the magnitude of the economic damage caused by avian influenza and the increasing likelihood of its endemicity, careful and quantitative analysis of outbreaks and the establishment of control policies are urgently needed.

  13. Field-trip guide to subaqueous volcaniclastic facies in the Ancestral Cascades arc in southern Washington State—The Ohanapecosh Formation and Wildcat Creek beds

    Science.gov (United States)

    Jutzeler, Martin; McPhie, Jocelyn

    2017-06-27

    Partly situated in the idyllic Mount Rainier National Park, this field trip visits exceptional examples of Oligocene subaqueous volcaniclastic successions in continental basins adjacent to the Ancestral Cascades arc. The >800-m-thick Ohanapecosh Formation (32–26 Ma) and the >300-m-thick Wildcat Creek (27 Ma) beds record similar sedimentation processes from various volcanic sources. Both show evidence of below-wave-base deposition, and voluminous accumulation of volcaniclastic facies from subaqueous density currents and suspension settling. Eruption-fed facies include deposits from pyroclastic flows that crossed the shoreline, from tephra fallout over water, and from probable Surtseyan eruptions, whereas re-sedimented facies comprise subaqueous density currents and debris flow deposits.

  14. Development of stereotactically guided laser interstitial thermotherapy of breast cancer: in situ measurement and analysis of the temperature field in ex vivo and in vivo adipose tissue.

    Science.gov (United States)

    Milne, P J; Parel, J M; Manns, F; Denham, D B; Gonzalez-Cirre, X; Robinson, D S

    2000-01-01

    The size (0.5-1.0 cm) of early nonpalpable breast tumors currently detected by mammography and confirmed by stereotactic core biopsy is of the order of the penetration depth of near infrared photons in breast tissue. In principle, stereotactically biopsied tumors, therefore, could be safely and efficiently treated with laser thermotherapy. The aim of the current study is to confirm the controlled heating produced by clinically relevant power levels delivered with an interstitial laser fiber optic probe adapted for use with stereotactic mammography and biopsy procedures. Temperature increases and the resultant thermal field produced by the irradiation of ex vivo (porcine and human) and in vivo (porcine) tissue models appropriate to the treatment of human breast tissue by using cw Nd:YAG laser radiation delivered with a interstitial fiber optic probe with a quartz diffusing tip, were recorded with an array of fifteen 23-gauge needle thermocouple probes connected to a laboratory computer-based data acquisition system. By using a stepwise decreasing power cycle to avoid tissue charring, acceptably symmetric thermal fields of repeatable volumetric dimensions were obtained. Reproducible thermal gradients and predictable tissue necrosis without carbonization could be induced in a 3-cm-diameter region around the fiber probe during a single treatment lasting only 3 minutes. The time-dependences of the temperature rise of the thermocouples surrounding the LITT probe were quantitatively modeled with simple linear functions during the applied laser heating cycles. Analysis of our experimental results show that reproducible, symmetric and predictable volumetric temperature increases in time can be reliably produced by interstitial laser thermotherapy. Copyright 2000 Wiley-Liss, Inc.

  15. Mosquito blood-meal analysis for avian malaria study in wild bird communities: laboratory verification and application to Culex sasai (Diptera: Culicidae) collected in Tokyo, Japan.

    Science.gov (United States)

    Kim, Kyeong Soon; Tsuda, Yoshio; Sasaki, Toshinori; Kobayashi, Mutsuo; Hirota, Yoshikazu

    2009-10-01

    We conducted laboratory experiments to verify molecular techniques of avian malaria parasite detection distinguishing between an infected mosquito (oocysts on midgut wall) and infective mosquito (sporozoites in salivary glands) in parallel with blood-meal identification from individual blood-fed mosquitoes prior to application to field survey for avian malaria. Domestic fowl infected with Plasmodium gallinaceum was exposed to a vector and non-vector mosquito species, Aedes aegypti and Culex pipiens pallens, respectively, to compare the time course of polymerase chain reaction (PCR) detection for parasite between competent and refractory mosquitoes. DNA of the domestic fowl was detectable for at least 3 days after blood feeding. The PCR-based detection of P. gallinaceum from the abdomen and thorax of A. aegypti corresponded to the microscopic observation of oocysts and sporozoites. Therefore, this PCR-based method was considered useful as one of the criteria to assess developmental stages of Plasmodium spp. in mosquito species collected in the field. We applied the same PCR-based method to 21 blood-fed C. sasai mosquitoes collected in Rinshi-no-mori Park in urban Tokyo, Japan. Of 15 blood meals of C. sasai successfully identified, 86.7% were avian-derived, 13.3% were bovine-derived. Plasmodium DNA was amplified from the abdomen of three C. sasai specimens having an avian blood meal from the Great Tit (Parus major), Pale Thrush (Turdus pallidus), and Jungle Crow (Corvus macrorhynchos). This is the first field study on host-feeding habits of C. sasai in relation to the potential role as a vector for avian malaria parasites transmitted in the Japanese wild bird community.

  16. Field-trip guide to Mount St. Helens, Washington - An overview of the eruptive history and petrology, tephra deposits, 1980 pyroclastic density current deposits, and the crater

    Science.gov (United States)

    Pallister, John S.; Clynne, Michael A.; Wright, Heather M.; Van Eaton, Alexa R.; Vallance, James W.; Sherrod, David R.; Kokelaar, B. Peter

    2017-08-02

    This field trip will provide an introduction to several fascinating features of Mount St. Helens. The trip begins with a rigorous hike of about 15 km from the Johnston Ridge Observatory (9 km north-northeast of the crater vent), across the 1980 Pumice Plain, to Windy Ridge (3.6 km northeast of the crater vent) to examine features that document the dynamics and progressive emplacement of pyroclastic flows. The next day, we examine classic tephra outcrops of the past 3,900 years and observe changes in thickness and character of these deposits as we traverse their respective lobes. We examine clasts in the deposits and discuss how the petrology and geochemistry of Mount St. Helens deposits reveal the evolution of the magmatic system through time. We also investigate the stratigraphy of the 1980 blast deposit and review the chronology of this iconic eruption as we travel through the remains of the blown-down forest. The third day is another rigorous hike, about 13 km round trip, climbing from the base of Windy Ridge (elevation 1,240 m) to the front of the Crater Glacier (elevation 1,700 m). En route we examine basaltic andesite and basalt lava flows emplaced between 1,800 and 1,700 years before present, a heterolithologic flow deposit produced as the 1980 blast and debris avalanche interacted, debris-avalanche hummocks that are stranded on the north flank and in the crater mouth, and shattered dacite lava domes that were emplaced between 3,900 and 2,600 years before present. These domes underlie the northern part of the volcano. In addition, within the crater we traverse well-preserved pyroclastic-flow deposits that were emplaced on the crater floor during the summer of 1980, and a beautiful natural section through the 1980 deposits in the upper canyon of the Loowit River.Before plunging into the field-trip log, we provide an overview of Mount St. Helens geology, geochemistry, petrology, and volcanology as background. The volcano has been referred to as a

  17. New oligonucleotide microarray for rapid diagnosis of avian viral diseases.

    Science.gov (United States)

    Sultankulova, Kulyaisan T; Kozhabergenov, Nurlan S; Strochkov, Vitaliy M; Burashev, Yerbol D; Shorayeva, Kamshat A; Chervyakova, Olga V; Rametov, Nurkuisa M; Sandybayev, Nurlan T; Sansyzbay, Abylay R; Orynbayev, Mukhit B

    2017-04-05

    We developed a new oligonucleotide microarray comprising 16 identical subarrays for simultaneous rapid detection of avian viruses: avian influenza virus (AIV), Newcastle disease virus (NDV), infection bronchitis virus (IBV), and infectious bursal disease virus (IBDV) in single- and mixed-virus infections. The objective of the study was to develop an oligonucleotide microarray for rapid diagnosis of avian diseases that would be used in the course of mass analysis for routine epidemiological surveillance owing to its ability to test one specimen for several infections. The paper describes the technique for rapid and simultaneous diagnosis of avian diseases such as avian influenza, Newcastle disease, infectious bronchitis and infectious bursal disease with use of oligonucleotide microarray, conditions for hybridization of fluorescent-labelled viral cDNA on the microarray and its specificity tested with use of AIV, NDV, IBV, IBDV strains as well as biomaterials from poultry. Sensitivity and specificity of the developed microarray was evaluated with use of 122 specimens of biological material: 44 cloacal swabs from sick birds and 78 tissue specimens from dead wild and domestic birds, as well as with use of 15 AIV, NDV, IBV and IBDV strains, different in their origin, epidemiological and biological characteristics (RIBSP Microbial Collection). This microarray demonstrates high diagnostic sensitivity (99.16% within 95% CI limits 97.36-100%) and specificity (100%). Specificity of the developed technique was confirmed by direct sequencing of NP and M (AIV), VP2 (IBDV), S1 (IBV), NP (NDV) gene fragments. Diagnostic effectiveness of the developed DNA microarray is 99.18% and therefore it can be used in mass survey for specific detection of AIV, NDV, IBV and IBDV circulating in the region in the course of epidemiological surveillance. Rather simple method for rapid diagnosis of avian viral diseases that several times shortens duration of assay versus classical diagnostic

  18. User Guide ECOREA-RICE (version 1.0). Program for assessing the transfer of radionuclides released accidentally onto flooded rice-fields

    International Nuclear Information System (INIS)

    Keum, Dong Kwon; Lee, Han Soo; Choi, Hei Hu; Kang, Hee Seok; Lee, Chang Woo

    2004-05-01

    The computer code ECOREA-RICE is a dynamic compartment model that is specially designed for estimating the transfer of radionuclides deposited onto flooded rice-fields after an accidental release. The model consists of six independent compartments including rice-body, grain, surface water, root-zone soil, fixed soil and deep soil, and takes into account the transfer processes including radioactive decay, percolation, leaching, shoot-base absorption, root-uptake, weathering, translocation, fixation in soil by adsorption and desorption, and soil-mixing by plowing. The rate of the change of radioactivity in compartments is expressed by a set of the first order ordinary differential equations, which are solved by the fourth order Runge-Kutta algorithm. Input to the program includes the deposition date, transplanting date, ear emergence date, harvest date, soil data, the biomass data of rice-plant, and rate constants associated with transfer processes. Output includes the list of input data, the activity of radionuclides in compartment, the rate constant, and the transfer factor of rice-body and grain with time

  19. Performance of an elliptically tapered neutron guide

    International Nuclear Information System (INIS)

    Muehlbauer, Sebastian; Stadlbauer, Martin; Boeni, Peter; Schanzer, Christan; Stahn, Jochen; Filges, Uwe

    2006-01-01

    Supermirror coated neutron guides are used at all modern neutron sources for transporting neutrons over large distances. In order to reduce the transmission losses due to multiple internal reflection of neutrons, ballistic neutron guides with linear tapering have been proposed and realized. However, these systems suffer from an inhomogeneous illumination of the sample. Moreover, the flux decreases significantly with increasing distance from the exit of the neutron guide. We propose using elliptically tapered guides that provide a more homogeneous phase space at the sample position as well as a focusing at the sample. Moreover, the design of the guide system is simplified because ellipses are simply defined by their long and short axes. In order to prove the concept we have manufactured a doubly focusing guide and investigated its properties with neutrons. The experiments show that the predicted gains using the program package McStas are realized. We discuss several applications of elliptic guides in various fields of neutron physics

  20. Reprint of: Overview of avian toxicity studies for the Deepwater Horizon Natural Resource Damage Assessment

    Science.gov (United States)

    Bursian, Steven J.; Alexander, C.R.; Cacela, Dave; Cunningham, Fred L.; Dean, Karen M.; Dorr, Brian S.; Ellis, Christine K.; Godard-Codding, Céline A.J.; Guglielmo, Christopher G.; Hanson-Dorr, Katie C.; Harr, Kendall E.; Healy, Katherine A.; Hooper, Michael J.; Horak, Katherine E.; Isanhart, John P.; Kennedy, Lisa V.; Link., Jane E.; Maggini, Ivan; Moye, John K.; Perez, Christina R.; Pritsos, Chris A.; Shriner, Susan A.; Trust, Kinberly A.; Tuttle, Peter L.

    2017-01-01

    The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1–20 ml of artificially weathered Mississippi Canyon 252 oil kg bw-1 day-1 from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts

  1. Rapid guiding center calculations

    International Nuclear Information System (INIS)

    White, R.B.

    1995-04-01

    Premature loss of high energy particles, and in particular fusion alpha particles, is very deleterious in a fusion reactor. Because of this it is necessary to make long-time simulations, on the order of the alpha particle slowing down time, with a number of test particles sufficient to give predictions with reasonable statistical accuracy. Furthermore it is desirable to do this for a large number of equilibria with different characteristic magnetic field ripple, to best optimize engineering designs. In addition, modification of the particle distribution due to magnetohydrodynamic (MHD) modes such as the saw tooth mode present in the plasma can be important, and this effect requires additional simulation. Thus the large number of necessary simulations means any increase of computing speed in guiding center codes is an important improvement in predictive capability. Previous guiding center codes using numerical equilibria such as ORBIT evaluated the local field strength and ripple magnitude using Lagrangian interpolation on a grid. Evaluation of these quantities four times per time step (using a fourth order Runge-Kutta routine) constitutes the major computational effort of the code. In the present work the authors represent the field quantities through an expansion in terms of pseudo-cartesian coordinates formed from the magnetic coordinates. The simplicity of the representation gives four important advantages over previous methods

  2. 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.

  3. Magnetically induced behaviour of ferritin corpuscles in avian ears: can cuticulosomes function as magnetosomes?

    Science.gov (United States)

    Jandacka, Petr; Burda, Hynek; Pistora, Jaromir

    2015-01-01

    Magnetoreception is an enigmatic, poorly understood sensory ability, described mainly on the basis of behavioural studies in animals of diverse taxa. Recently, corpuscles containing superparamagnetic iron-storage protein ferritin were found in the inner ear hair cells of birds, a predominantly single ferritin corpuscle per cell. It was suggested that these corpuscles might represent magnetosomes and function as magnetosensors. Here we determine ferritin low-field paramagnetic susceptibility to estimate its magnetically induced intracellular behaviour. Physical simulations show that ferritin corpuscles cannot be deformed or rotate in weak geomagnetic fields, and thus cannot provide magnetoreception via deformation of the cuticular plate. Furthermore, we reached an alternative hypothesis that ferritin corpuscle in avian ears may function as an intracellular electromagnetic oscillator. Such an oscillator would generate additional cellular electric potential related to normal cell conditions. Though the phenomenon seems to be weak, this effect deserves further analyses. PMID:25551148

  4. Molecular diversity of avian schistosomes in Danish freshwater snails

    DEFF Research Database (Denmark)

    Christiansen, Anne Ø.; Olsen, Annette; Buchmann, Kurt

    2016-01-01

    Avian schistosomes are widespread parasites of snails and waterfowl and may cause cercarial dermatitis (swimmer's itch) in humans, a disease that is frequently reported in European countries. These parasites are known to occur in Denmark, but here, we applied a new approach using molecular tools...... to identify the parasites at species level. In order to do that, 499 pulmonate freshwater snails (Radix sp., Lymnaea stagnalis, Stagnicola sp. and Planorbarius corneus) were sampled from 12 lakes, ponds, and marshes in the greater Copenhagen area. Avian schistosome cercariae were identified by microscopy...

  5. Movements of Birds and Avian Influenza from Asia into Alaska

    OpenAIRE

    Winker, Kevin; McCracken, Kevin G.; Gibson, Daniel D.; Pruett, Christin L.; Meier, Rose; Huettmann, Falk; Wege, Michael; Kulikova, Irina V.; Zhuravlev, Yuri N.; Perdue, Michael L.; Spackman, Erica; Suarez, David L.; Swayne, David E.

    2007-01-01

    Asian-origin avian influenza (AI) viruses are spread in part by migratory birds. In Alaska, diverse avian hosts from Asia and the Americas overlap in a region of intercontinental avifaunal mixing. This region is hypothesized to be a zone of Asia-to-America virus transfer because birds there can mingle in waters contaminated by wild-bird?origin AI viruses. Our 7 years of AI virus surveillance among waterfowl and shorebirds in this region (1998?2004; 8,254 samples) showed remarkably low infecti...

  6. Avian influenza: The tip of the iceberg

    Directory of Open Access Journals (Sweden)

    Balkhy Hanan

    2008-01-01

    Full Text Available 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 Hong Kong that led to the transmission of infection to 18 humans with close contact with diseased birds; there were six reported deaths. [1] In 2003, with the reemergence of H5N1 (considered the most likely AI virus in the Republic of Korea and its subsequent spread to Thailand, Vietnam, Hong Kong and China. Many countries started aggressively making preparations to meet the threat. [2] The pressure for real action from governments has increased. Most developed countries have requested increased funding for the search for a more effective vaccine, for stockpiling possibly helpful antiviral drugs, and for intensifying domestic and global surveillance. [3] Most countries, however, continue to be inadequately prepared for such an epidemic, especially with regard to animal surveillance in the farm market and surveillance among migratory birds. Even now, most countries do not have the ability to detect disease among humans in the early stages of an outbreak nor do most hospitals comply with effective infection control measures that could curtail the spread of the virus in the early stages of an epidemic. In Saudi Arabia we are rapidly implementing many of these measures. [4

  7. Aerosolized avian influenza virus by laboratory manipulations

    Directory of Open Access Journals (Sweden)

    Li Zhiping

    2012-08-01

    Full Text Available 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 to process the influenza virus were carried out independently and the amount of virus polluting the on-site atmosphere was measured. In particular, zootomy, grinding, centrifugation, pipetting, magnetic stirring, egg inoculation, and experimental zoogenetic infection were performed. In addition, common accidents associated with each process were simulated, including breaking glass containers, syringe injection of influenza virus solution, and rupturing of centrifuge tubes. A micro-cluster sampling ambient air pollution collection device was used to collect air samples. The collected viruses were tested for activity by measuring their ability to induce hemagglutination with chicken red blood cells and to propagate in chicken embryos after direct inoculation, the latter being detected by reverse-transcription PCR and HA test. The results showed that the air samples from the normal centrifugal group and the negative-control group were negative, while all other groups were positive for H5N1. Conclusions Our findings suggest that there are numerous sources of aerosols in laboratory operations involving H5N1. Thus, laboratory personnel should be aware of the exposure risk that accompanies routine procedures involved in H5N1 processing and take proactive measures to prevent accidental infection and decrease the risk of virus aerosol leakage beyond the laboratory.

  8. 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.

  9. Avian influenza in Chile: a successful experience.

    Science.gov (United States)

    Max, Vanessa; Herrera, José; Moreira, Rubén; Rojas, Hernán

    2007-03-01

    Avian influenza (AI) was diagnosed in May 2002 for the first time in Chile and South America. The epidemic was caused by the highly pathogenic AI (HPAI) virus subtype H7N3 that emerged from a low pathogenic virus. The index farm was a broiler breeder, located in San Antonio, V Region, which at the time was a densely populated poultry area. Stamping of 465,000 breeders, in 27 sheds, was immediately conducted. Surveillance activities detected a second outbreak, 1 wk later, at a turkey breeding farm from the same company. The second farm was located 4 km from the index case. Only 25% of the sheds were infected, and 18,500 turkeys were destroyed. In both outbreaks, surveillance zones and across-country control measures were established: prediagnosis quarantine, depopulation, intensive surveillance, movement control, and increased biosecurity. Other measures included cleaning, disinfection, and controlling the farms with sentinels to detect the potential presence of the virus. Zoning procedures were implemented to allow the international trade of poultry products from unaffected areas. Positive serologic results to H5N2 virus also were detected in other poultry farms, but there was no evidence of clinical signs or virus isolation. Epidemiological investigation and laboratory confirmation determined that positive serology was related to a contaminated imported batch of vaccine against inclusion body hepatitis. All actions taken allowed the control of the epidemic, and within 7 mo, Chile was free of AI. Epidemic and control measures that prevented further spread are described in this article, which illustrates the importance of a combination of control measures during and after an outbreak of AI. This study is a good example of how veterinary services need to respond if their country is affected by HPAI.

  10. Diversity and distribution of avian haemosporidians in sub-Saharan Africa: an inter-regional biogeographic overview.

    Science.gov (United States)

    Outlaw, Diana C; Harvey, Johanna A; Drovetski, Sergei V; Voelker, Gary

    2017-04-01

    The diversity of avian malaria parasites is much greater than 20th century morphologists realized and virtually every study in this field in the last 15 years has uncovered previously undocumented diversity at multiple levels within the taxonomic hierarchy. Despite this explosion of knowledge, there remain vast sampling gaps, both geographically and host-taxonomically, which makes characterizing patterns of diversity extremely challenging. Here, we summarize the current state of knowledge of sub-Saharan African avian malaria parasite diversity, focusing on avian hosts endemic to Africa. The relative proportions of the parasite genera included here, Plasmodium, Haemoproteus (including Parahaemoproteus) and Leucocytozoon, varied between regions, in part due to habitat preferences of the insect vectors of these genera, and in part we believe due to sampling bias. Biogeographic regions of sub-Saharan Africa harbour about the same proportion of endemic to shared parasite lineages, but there appears to be no phylogenetic structuring across regions. Our results highlight the sampling problem that must be addressed if we are to have a detailed understanding of parasite diversity in Africa. Without broad sampling within and across regions and hosts, using both molecular tools and microscopy, conclusions about parasite diversity, host-parasite interactions or even transmission dynamics remain extremely limited.

  11. 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

  12. The same clade of Clostridium botulinum strains is causing avian botulism in southern and northern Europe.

    Science.gov (United States)

    Anza, Ibone; Skarin, Hanna; Vidal, Dolors; Lindberg, Anna; Båverud, Viveca; Mateo, Rafael

    2014-04-01

    Avian botulism is a paralytic disease caused by Clostridium botulinum-produced botulinum neurotoxins (BoNTs), most commonly of type C/D. It is a serious disease of waterbirds and poultry flocks in many countries in Europe. The objective of this study was to compare the genetic relatedness of avian C. botulinum strains isolated in Spain with strains isolated in Sweden using pulsed-field gel electrophoresis (PFGE). Fifteen strains were isolated from Spanish waterbirds using an immunomagnetic separation technique. Isolates were characterized by PCR, and all were identified as the genospecies Clostridium novyi sensu lato and eight harboured the gene coding for the BoNT type C/D. PFGE analysis of the strains revealed four highly similar pulsotypes, out of which two contained strains from both countries. It also showed that outbreaks in wild and domestic birds can be caused by the same strains. These results support a clonal spreading of the mosaic C. botulinum type C/D through Europe and give relevant information for future epidemiological studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Virulence-associated genes in avian pathogenic Escherichia coli from laying hens in Apulia, Southern Italy.

    Science.gov (United States)

    Circella, E; Pennelli, D; Tagliabue, S; Camarda, A

    2012-01-01

    1. Escherichia coli isolated from lesions (Avian Pathogenic E. coli - APEC) of layer hens affected by colibacillosis and from intestinal contents of clinically-healthy birds (Avian Faecal E. coli - AFEC) were serotyped. All the isolates were investigated for the presence of virulence genes to determine which genes were more closely related to those from lesions. 2. A number of different serogroups were detected, O78 being predominant among the isolates from colibacillosis. 3. E. coli isolated from lesions were not linked to a specific pathotype (set of common virulence genes). 4. The presence of the virulence genes, with the exception of astA, was associated more generally with APEC strains. 5. Statistically, genes such as cva/cvi, tsh, iss, irp2 and iucD were more related to isolates from colibacillosis. 6. It is suggested that the detection of these genes in a rapid and inexpensive test for field practitioners could provide useful information about the potential virulence of E. coli isolated in commercial layer flocks.

  14. Novel means of viral antigen identification: improved detection of avian influenza viruses by proximity ligation.

    Science.gov (United States)

    Schlingemann, Joerg; Leijon, Mikael; Yacoub, Alia; Schlingemann, Heidi; Zohari, Siamak; Matyi-Tóth, Anna; Kiss, István; Holmquist, Göran; Nordengrahn, Ann; Landegren, Ulf; Ekström, Björn; Belák, Sándor

    2010-01-01

    Recent outbreaks of avian influenza in different parts of the world have caused major economic losses for the poultry industry, affected wildlife seriously and present a significant threat even to human public health, due to the risk for zoonotic transmission. The ability to recognize avian influenza viruses (AIVs) early is of paramount importance to ensure that appropriate measures can be taken quickly to contain the outbreak. In this study, the performance of a proximity ligation assay (PLA) for the detection of AIV antigens in biological specimens was evaluated. It is shown that PLA: (i) as a novel principle of highly sensitive antigen detection is extending the arsenal of tools for the diagnosis of AIV; (ii) is very specific, nearly as sensitive as a commonly used reference real-time PCR assay, and four orders of magnitude more sensitive than a sandwich ELISA, utilizing the same antibody; (iii) avoids the necessity of nucleic acids extraction, which greatly facilitates high-throughput implementations; (iv) allows the use of inactivated samples, which safely can be transported from the field to diagnostic laboratories for further analysis. In summary, the results demonstrate that PLA is suited for rapid, accurate and early detection of AIV.

  15. High resolution micro-XRF maps of iron oxides inside sensory dendrites of putative avian magnetoreceptors

    International Nuclear Information System (INIS)

    Falkenberg, G; Fleissner, G E; Fleissner, G U E; Schuchardt, K; Kuehbacher, M; Chalmin, E; Janssens, K

    2009-01-01

    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 μm the microarchitecture of the dendrites can be considered as undisturbed and artefacts introduced by sectioning might be widely reduced.

  16. 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.

  17. 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 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.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.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.

  18. Sedimentology and reservoir heterogeneity of a valley-fill deposit-A field guide to the Dakota Sandstone of the San Rafael Swell, Utah

    Science.gov (United States)

    Kirschbaum, Mark A.; Schenk, Christopher J.

    2010-01-01

    different scales of fluid-flow compartmentalization present a challenge to hydrocarbon exploration targeting paleovalley deposits, and producing fields containing these types of reservoirs may have significant bypassed pay, especially where well spacing is large.

  19. Reanalysis of Wupus agilis (Early Cretaceous) of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks.

    Science.gov (United States)

    Xing, Lida; Buckley, Lisa G; McCrea, Richard T; Lockley, Martin G; Zhang, Jianping; Piñuela, Laura; Klein, Hendrik; Wang, Fengping

    2015-01-01

    Trace fossils provide the only records of Early Cretaceous birds from many parts of the world. The identification of traces from large avian track-makers is made difficult given their overall similarity in size and tridactyly in comparison with traces of small non-avian theropods. Reanalysis of Wupus agilis from the Early Cretaceous (Aptian-Albian) Jiaguan Formation, one of a small but growing number of known avian-pterosaur track assemblages, of southeast China determines that these are the traces of a large avian track-maker, analogous to extant herons. Wupus, originally identified as the trace of a small non-avian theropod track-maker, is therefore similar in both footprint and trackway characteristics to the Early Cretaceous (Albian) large avian trace Limiavipes curriei from western Canada, and Wupus is reassigned to the ichnofamily Limiavipedidae. The reanalysis of Wupus reveals that it and Limiavipes are distinct from similar traces of small to medium-sized non-avian theropods (Irenichnites, Columbosauripus, Magnoavipes) based on their relatively large footprint length to pace length ratio and higher mean footprint splay, and that Wupus shares enough characters with Limiavipes to be reassigned to the ichnofamily Limiavipedidae. The ability to discern traces of large avians from those of small non-avian theropods provides more data on the diversity of Early Cretaceous birds. This analysis reveals that, despite the current lack of body fossils, large wading birds were globally distributed in both Laurasia and Gondwana during the Early Cretaceous.

  20. Reanalysis of Wupus agilis (Early Cretaceous of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks.

    Directory of Open Access Journals (Sweden)

    Lida Xing

    Full Text Available Trace fossils provide the only records of Early Cretaceous birds from many parts of the world. The identification of traces from large avian track-makers is made difficult given their overall similarity in size and tridactyly in comparison with traces of small non-avian theropods. Reanalysis of Wupus agilis from the Early Cretaceous (Aptian-Albian Jiaguan Formation, one of a small but growing number of known avian-pterosaur track assemblages, of southeast China determines that these are the traces of a large avian track-maker, analogous to extant herons. Wupus, originally identified as the trace of a small non-avian theropod track-maker, is therefore similar in both footprint and trackway characteristics to the Early Cretaceous (Albian large avian trace Limiavipes curriei from western Canada, and Wupus is reassigned to the ichnofamily Limiavipedidae. The reanalysis of Wupus reveals that it and Limiavipes are distinct from similar traces of small to medium-sized non-avian theropods (Irenichnites, Columbosauripus, Magnoavipes based on their relatively large footprint length to pace length ratio and higher mean footprint splay, and that Wupus shares enough characters with Limiavipes to be reassigned to the ichnofamily Limiavipedidae. The ability to discern traces of large avians from those of small non-avian theropods provides more data on the diversity of Early Cretaceous birds. This analysis reveals that, despite the current lack of body fossils, large wading birds were globally distributed in both Laurasia and Gondwana during the Early Cretaceous.