WorldWideScience

Sample records for avian igy-fc fragment

  1. Landscape fragmentation affects responses of avian communities to climate change.

    Science.gov (United States)

    Jarzyna, Marta A; Porter, William F; Maurer, Brian A; Zuckerberg, Benjamin; Finley, Andrew O

    2015-08-01

    Forecasting the consequences of climate change is contingent upon our understanding of the relationship between biodiversity patterns and climatic variability. While the impacts of climate change on individual species have been well-documented, there is a paucity of studies on climate-mediated changes in community dynamics. Our objectives were to investigate the relationship between temporal turnover in avian biodiversity and changes in climatic conditions and to assess the role of landscape fragmentation in affecting this relationship. We hypothesized that community turnover would be highest in regions experiencing the most pronounced changes in climate and that these patterns would be reduced in human-dominated landscapes. To test this hypothesis, we quantified temporal turnover in avian communities over a 20-year period using data from the New York State Breeding Atlases collected during 1980-1985 and 2000-2005. We applied Bayesian spatially varying intercept models to evaluate the relationship between temporal turnover and temporal trends in climatic conditions and landscape fragmentation. We found that models including interaction terms between climate change and landscape fragmentation were superior to models without the interaction terms, suggesting that the relationship between avian community turnover and changes in climatic conditions was affected by the level of landscape fragmentation. Specifically, we found weaker associations between temporal turnover and climatic change in regions with prevalent habitat fragmentation. We suggest that avian communities in fragmented landscapes are more robust to climate change than communities found in contiguous habitats because they are comprised of species with wider thermal niches and thus are less susceptible to shifts in climatic variability. We conclude that highly fragmented regions are likely to undergo less pronounced changes in composition and structure of faunal communities as a result of climate change

  2. Complementary seed dispersal by three avian frugivores in a fragmented Afromontane forest

    NARCIS (Netherlands)

    Lehouck, V.; Spanhove, T.; Demeter, S.; Groot, N.E.; Lens, L.

    2009-01-01

    Questions To what extent does species-specific variation in gut passage time (GPT), habitat use and mobility of three key avian frugivores synergistically affect the distribution of Xymalos monospora seeds within and among isolated forest fragments? Location Three fragments of a severely fragmented

  3. Matrix intensification alters avian functional group composition in adjacent rainforest fragments.

    Directory of Open Access Journals (Sweden)

    Justus P Deikumah

    Full Text Available Conversion of farmland land-use matrices to surface mining is an increasing threat to the habitat quality of forest remnants and their constituent biota, with consequences for ecosystem functionality. We evaluated the effects of matrix type on bird community composition and the abundance and evenness within avian functional groups in south-west Ghana. We hypothesized that surface mining near remnants may result in a shift in functional composition of avifaunal communities, potentially disrupting ecological processes within tropical forest ecosystems. Matrix intensification and proximity to the remnant edge strongly influenced the abundance of members of several functional guilds. Obligate frugivores, strict terrestrial insectivores, lower and upper strata birds, and insect gleaners were most negatively affected by adjacent mining matrices, suggesting certain ecosystem processes such as seed dispersal may be disrupted by landscape change in this region. Evenness of these functional guilds was also lower in remnants adjacent to surface mining, regardless of the distance from remnant edge, with the exception of strict terrestrial insectivores. These shifts suggest matrix intensification can influence avian functional group composition and related ecosystem-level processes in adjacent forest remnants. The management of matrix habitat quality near and within mine concessions is important for improving efforts to preserveavian biodiversity in landscapes undergoing intensification such as through increased surface mining.

  4. An Immunosensor Based on Antibody Binding Fragments Attached to Gold Nanoparticles for the Detection of Peptides Derived from Avian Influenza Hemagglutinin H5

    Directory of Open Access Journals (Sweden)

    Urszula Jarocka

    2014-08-01

    Full Text Available This paper concerns the development of an immunosensor for detection of peptides derived from avian influenza hemagglutinin H5. Its preparation consists of successive gold electrode modification steps: (i modification with 1,6-hexanedithiol and gold colloidal nanoparticles; (ii immobilization of antibody-binding fragments (Fab’ of anti-hemagglutinin H5 monoclonal antibodies Mab 6-9-1 via S-Au covalent bonds; and (iii covering the remaining free space on the electrode surfaces with bovine serum albumin. The interactions between Fab’ fragments and hemagglutinin (HA variants have been explored with electrochemical impedance spectroscopy (EIS in the presence of [Fe(CN6]3−/4− as an electroactive marker. The immunosensor was able to recognize three different His-tagged variants of recombinant hemagglutinin from H5N1 viruses: H1 subunit (17–340 residues of A/swan/Poland/305-135V08/2006, the long HA (17–530 residues A/Bar-headed Goose/Qinghai/12/2005 and H1 subunit (1–345 residues of A/Vietnam/1194/2004. The strongest response has been observed for the long variant with detection limit of 2.2 pg/mL and dynamic range from 4.0 to 20.0 pg/mL.

  5. Molecular analysis of hemagglutinin-1 fragment of avian influenza H5N1 viruses isolated from chicken farms in Indonesia from 2008 to 2010.

    Science.gov (United States)

    Mahardika, Gusti N; Jonas, Melina; Murwijati, Theresia; Fitria, Nur; Suartha, I Nyoman; Suartini, I Gusti A A; Wibawan, I Wayan Teguh

    2016-04-15

    Highly pathogenic avian influenza virus of subtype H5N1 (AIV-H5N1) has been circulating in Indonesia since 2003. To understand the genetic diversity of these viruses, and to predict vaccine efficacy, the hemaglutinin-1 (HA-1) fragment of viruses isolated from chicken farms in Indonesia from 2008 to 2010 was sequenced and analyzed. The effects of these molecular changes were investigated in challenge experiments and HI assays of homologous and heterologous strains. Molecular analysis showed that these AIV-H5N1 isolates had evolved into three distinct sub-lineages from an ancestor circulating since 2003. Although no significant positive selection of residues was detected, 12 negatively selected sites were identified (p<0.05). Moreover, four sites showed evidence of significant episodic diversifying selection. The findings indicated complete protectivity and high HI titers with homologous strains, compared with protectivity ranging from 40 to 100% and lower HI titers with heterologous strains resulting from polymorphisms at antigenic sites. Our findings provide valuable insight into the molecular evolution of AIV and have important implications for vaccine efficacy and future vaccination strategies.

  6. Avian cardiology.

    Science.gov (United States)

    Strunk, Anneliese; Wilson, G Heather

    2003-01-01

    The field of avian cardiology is continually expanding. Although a great deal of the current knowledge base has been derived from poultry data, research and clinical reports involving companion avian species have been published. This article will present avian cardiovascular anatomy and physiology, history and physical examination considerations in the avian cardiac disease patient, specific diagnostic tools, cardiovascular disease processes, and current therapeutic modalities.

  7. 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.

  8. Identification of Avian Leukosis Virus Using Polymerase Chain Reaction and Restriction Fragment Length Polymorphism(PCR/RFLP)%PCR/RFLP鉴别禽白血病病毒

    Institute of Scientific and Technical Information of China (English)

    刘公平; 刘福安; 赵振芬

    2001-01-01

    用PCR方法从禽白血病病毒(avian leukosis virus,ALV)亚群毒株RAV-1、RAV-2感染或未感染的SPF鸡胚成纤维细胞(CEF)分别扩增出1.2 kb基因片段。RAV-1囊膜基因可被BglⅡ分为2条相近的600 bp片段,RAV-2囊膜基因被BamHⅠ分为2条约600 bp片段,对照组基因片段(内源性病毒)不被BglⅡ和BamHⅠ切割。结果显示,ALV囊膜基因的PCR/RFLP可用于诊断禽白血病和鉴别不同的ALV毒株。

  9. Avian Wings

    Science.gov (United States)

    Liu, Tianshu; Kuykendoll, K.; Rhew, R.; Jones, S.

    2004-01-01

    This paper describes the avian wing geometry (Seagull, Merganser, Teal and Owl) extracted from non-contact surface measurements using a three-dimensional laser scanner. The geometric quantities, including the camber line and thickness distribution of airfoil, wing planform, chord distribution, and twist distribution, are given in convenient analytical expressions. Thus, the avian wing surfaces can be generated and the wing kinematics can be simulated. The aerodynamic characteristics of avian airfoils in steady inviscid flows are briefly discussed. The avian wing kinematics is recovered from videos of three level-flying birds (Crane, Seagull and Goose) based on a two-jointed arm model. A flapping seagull wing in the 3D physical space is re-constructed from the extracted wing geometry and kinematics.

  10. Avian influenza

    Science.gov (United States)

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

  11. Avian Influenza

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a letter from a professor at Clemson University about waterfowl that had been tested for avian influenza at Santee National Wildlife Refuge

  12. Avian hematology.

    Science.gov (United States)

    Jones, Michael P

    2015-01-01

    Avian veterinarians often rely heavily on the results of various diagnostic tests, including hematology results. As such, cellular identification and evaluation of the cellular response are invaluable tools that help veterinarians understand the health or condition of their patient, as well as to monitor severity and clinical progression of disease and response to treatment. Therefore, it is important to thoroughly understand how to identify and evaluate changes in the avian erythron and leukon, as well as to interpret normal and abnormal results.

  13. Avian Flu

    Energy Technology Data Exchange (ETDEWEB)

    Eckburg, Paul

    2006-11-06

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

  14. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

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

  15. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

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

  16. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

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

  17. Avian diversity in five fragments of Atlantic Rainforest at Usina São José, Igarassu, Northern Pernambuco State, Brazil

    Directory of Open Access Journals (Sweden)

    Ana Carolina Borges Lins e Silva

    2007-12-01

    Full Text Available In northeastern Brazil, most well-preserved Atlantic Rainforest fragments are situated within privately-owned lands or sugarcane properties, mainly in the states of Alagoas and Pernambuco. On the lands of São José Sugar Mill (USJ, in Igarassu (Pernambuco, there are 106 forest patches totaling 6,660ha, surrounded by sugarcane fields. The main goal of this study was to determine the species richness in five forest remnants within the USJ property. We completed 77 hours of observation and recording of bird voices, using binoculars and a tape recorder with a unidirectional microphone. A total of 184 bird species were registered, among which 15 were under risk of extinction, (e.g. Cercomacra laeta sabinoi, Pyriglena leuconota pernambucensis and Myrmeciza rufi cauda soror. Some species that were observed and collected in the same region in the 1940s, such as Ramphastos vitellinus, Pteroglossus aracari and Lipaugus vociferans, were not registered during the study period.

  18. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

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

  19. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

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

  20. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

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

  1. Avian Research

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

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

  2. Avian Influenza in Birds

    Science.gov (United States)

    ... this? Submit Button Past Newsletters Avian Influenza in Birds Language: English Español Recommend on Facebook Tweet ... illness. Top of Page Avian Influenza in Wild Birds Avian influenza A viruses have been isolated from ...

  3. 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

  4. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... files Questions & answers Features Multimedia Contacts Avian and other zoonotic influenza Fact sheet Updated November 2016 Key ... A(H3) subtypes. Clinical features of avian and other zoonotic influenza infections in humans Avian and other ...

  5. Avian Chlamydiosis Zoonotic Disease.

    Science.gov (United States)

    Szymańska-Czerwińska, Monika; Niemczuk, Krzysztof

    2016-01-01

    This review presents recent data about avian chlamydiosis. Chlamydia psittaci has been considered to be the main causative agent of chlamydiosis in birds; however, two new Chlamydia species have been detected recently-C. gallinacea in breeding birds and C. avium in wild birds. We discuss the zoonotic potential of avian Chlamydia species.

  6. Quantum fragmentation

    CERN Document Server

    Peschanski, R

    1993-01-01

    Phenomenological and theoretical aspects of fragmentation for elementary particles (resp. nuclei) are discussed. It is shown that some concepts of classical fragmentation remain relevant in a microscopic framework, exhibiting non-trivial properties of quantum relativistic field theory (resp. lattice percolation). Email contact: pesch@amoco.saclay.cea.fr

  7. Editorial: Avian Research

    Institute of Scientific and Technical Information of China (English)

    Yong; Wang; Guangmei; Zheng

    2014-01-01

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

  8. Lesions of the avian pancreas.

    Science.gov (United States)

    Schmidt, Robert E; Reavill, Drury R

    2014-01-01

    Although not well described, occasional reports of avian exocrine and endocrine pancreatic disease are available. This article describes the lesions associated with common diseases of the avian pancreas reported in the literature and/or seen by the authors.

  9. Magma Fragmentation

    Science.gov (United States)

    Gonnermann, Helge M.

    2015-05-01

    Magma fragmentation is the breakup of a continuous volume of molten rock into discrete pieces, called pyroclasts. Because magma contains bubbles of compressible magmatic volatiles, decompression of low-viscosity magma leads to rapid expansion. The magma is torn into fragments, as it is stretched into hydrodynamically unstable sheets and filaments. If the magma is highly viscous, resistance to bubble growth will instead lead to excess gas pressure and the magma will deform viscoelastically by fracturing like a glassy solid, resulting in the formation of a violently expanding gas-pyroclast mixture. In either case, fragmentation represents the conversion of potential energy into the surface energy of the newly created fragments and the kinetic energy of the expanding gas-pyroclast mixture. If magma comes into contact with external water, the conversion of thermal energy will vaporize water and quench magma at the melt-water interface, thus creating dynamic stresses that cause fragmentation and the release of kinetic energy. Lastly, shear deformation of highly viscous magma may cause brittle fractures and release seismic energy.

  10. Fragmented Authoritarianism or Integrated Fragmentation

    DEFF Research Database (Denmark)

    Brødsgaard, Kjeld Erik

    of these business leaders prompts the question of whether we are seeing the development of distinct interest groups that could challenge Party and state authority and create a fragmented polity. However, through the nomenklatura system the Party has an important instrument of control to wield over business groups....... Through this system the Party controls the appointment and promotion of the heads of the most important state-owned enterprises. The nomenklatura system also enables the Party to rotate leaders in big business from a position as CEO in one company to a similar position in another state-owned company...... and the Party-state, I suggest the notion of integrated fragmentation....

  11. Avian influenza control strategies

    Science.gov (United States)

    Control strategies for avian influenza in poultry vary depending on whether the goal is prevention, management, or eradication. Components used in control programs include: 1) education which includes communication, public awareness, and behavioral change, 2) changes to production and marketing sys...

  12. Avian influenza virus

    Science.gov (United States)

    Avian influenza (AI) is caused by type A influenza virus, a member of the Orthomyxoviridae family. AI viruses are serologically categorized into 16 hemagglutinin (H1-H16) and 9 neuraminidase (N1-N9) subtypes. All subtypes have been identified in birds. Infections by AI viruses have been reported in ...

  13. Bespoke Fragments

    DEFF Research Database (Denmark)

    Kruse Aagaard, Anders

    2016-01-01

    The Ph.D. -project Bespoke Fragments seeks to explore and utilise the space emerging between the potentials of digital drawing and fabrication and the field of materials and their properties and capacities. Within this span, the project is situated in a shuttling between the virtual and the actual......, the emergence of virtual space is no longer limited to the computer's digital world, but extends into the materials' world. Creation and uncertainty are allowed as virtual parameters in both the digital and reality. Based on this notion the project suggests utilising that exact potential to develop...

  14. BIRD FLU (AVIAN INFLUENZA)

    OpenAIRE

    Ali ACAR; Bulent BESIRBELLIOÐLU

    2005-01-01

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

  15. Framing Fragmentation

    DEFF Research Database (Denmark)

    Bundgaard, Charlotte

    2009-01-01

    , contain distinctive architectural traits, not only based on rational repetition, but also supporting composition and montage as dynamic concepts. Prefab architecture is an architecture of fragmentation, individualization and changeability, and this sets up new challenges for the architect. This paper...... tries to develop a strategy for the architect dealing with industrially based architecture; a strategy which exploits architectural potentials in industrial building, which recognizes the rules of mass production and which redefines the architect’s position among the agents of building. If recent...... developments within the construction sector imply a marginalized role for the architect, this strategy suggests a strong repositioning. In Danish building practice the construction industry is increasingly organized within terms like ”systemized prefab delivery” and ”digital building”. The building is divided...

  16. 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...

  17. Koyukuk NWR 1985 avian checklist

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An avian checklist survey was conducted within the boundaries of the Koyukuk National Wildlife Refuge and Kaiyuh Flats unit of the Innoko National Wildlife Refuge...

  18. Koyukuk NWR 1986 avian checklist

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An avian checklist survey was conducted within the boundaries of the Koyukuk National Wildlife Refuge and Kaiyuh Flats unit of the Innoko National Wildlife Refuge in...

  19. Simulating avian wingbeat kinematics.

    Science.gov (United States)

    Parslew, Ben; Crowther, William J

    2010-12-01

    Inverse dynamics methods are used to simulate avian wingbeats in varying flight conditions. A geometrically scalable multi-segment bird model is constructed, and optimisation techniques are employed to determine segment motions that generate desired aerodynamic force coefficients with minimal mechanical power output. The results show that wingbeat kinematics vary gradually with changes in cruise speed, which is consistent with experimental data. Optimised solutions for cruising flight of the pigeon suggest that upstroke wing retraction is used as a method of saving energy. Analysis of the aerodynamic force coefficient variation in high and low speed cruise leads to the proposal that a suitable gait metric should include both thrust and lift generation during each half-stroke.

  20. Avian host defense peptides.

    Science.gov (United States)

    Cuperus, Tryntsje; Coorens, Maarten; van Dijk, Albert; Haagsman, Henk P

    2013-11-01

    Host defense peptides (HDPs) are important effector molecules of the innate immune system of vertebrates. These antimicrobial peptides are also present in invertebrates, plants and fungi. HDPs display broad-spectrum antimicrobial activities and fulfill an important role in the first line of defense of many organisms. It is becoming increasingly clear that in the animal kingdom the functions of HDPs are not confined to direct antimicrobial actions. Research in mammals has indicated that HDPs have many immunomodulatory functions and are also involved in other physiological processes ranging from development to wound healing. During the past five years our knowledge about avian HDPs has increased considerably. This review addresses our current knowledge on the evolution, regulation and biological functions of HDPs of birds.

  1. BIRD FLU (AVIAN INFLUENZA

    Directory of Open Access Journals (Sweden)

    Ali ACAR

    2005-12-01

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

  2. Protection of chickens against avian hepatitis E virus (avian HEV) infection by immunization with recombinant avian HEV capsid protein.

    Science.gov (United States)

    Guo, H; Zhou, E M; Sun, Z F; Meng, X J

    2007-04-12

    Avian hepatitis E virus (avian HEV) is an emerging virus associated with hepatitis-splenomegaly syndrome in chickens in North America. Avian HEV is genetically and antigenically related to human HEV, the causative agent of hepatitis E in humans. In the lack of a practical animal model, avian HEV infection in chickens has been used as a model to study human HEV replication and pathogenesis. A 32 kDa recombinant ORF2 capsid protein of avian HEV expressed in Escherichia coli was found having similar antigenic structure as that of human HEV containing major neutralizing epitopes. To determine if the capsid protein of avian HEV can be used as a vaccine, 20 chickens were immunized with purified avian HEV recombinant protein with aluminum as adjuvant and another 20 chickens were mock immunized with KLH precipitated in aluminum as controls. Both groups of chickens were subsequently challenged with avian HEV. All the tested mock-immunized control chickens developed typical avian HEV infection characterized by viremia, fecal virus shedding and seroconversion to avian HEV antibodies. Gross hepatic lesions were also found in portion of these chickens. In contrast, none of the tested chickens immunized with avian HEV capsid protein had detectable viremia, fecal virus shedding or observable gross hepatitis lesions. The results from this study suggested that immunization of chickens with avian HEV recombinant ORF2 capsid protein with aluminum as adjuvant can induce protective immunity against avian HEV infection. Chickens are a useful small animal model to study anti-HEV immunity and pathogenesis.

  3. 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...

  4. Markov Chain Estimation of Avian Seasonal Fecundity

    Science.gov (United States)

    To explore the consequences of modeling decisions on inference about avian seasonal fecundity we generalize previous Markov chain (MC) models of avian nest success to formulate two different MC models of avian seasonal fecundity that represent two different ways to model renestin...

  5. 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.

  6. 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.

  7. Effect of fragmentation on the Costa Rican dry forest avifauna

    Science.gov (United States)

    Barrantes, Gilbert; Ocampo, Diego; Ramírez-Fernández, José D.

    2016-01-01

    Deforestation and changes in land use have reduced the tropical dry forest to isolated forest patches in northwestern Costa Rica. We examined the effect of patch area and length of the dry season on nestedness of the entire avian community, forest fragment assemblages, and species occupancy across fragments for the entire native avifauna, and for a subset of forest dependent species. Species richness was independent of both fragment area and distance between fragments. Similarity in bird community composition between patches was related to habitat structure; fragments with similar forest structure have more similar avian assemblages. Size of forest patches influenced nestedness of the bird community and species occupancy, but not nestedness of assemblages across patches in northwestern Costa Rican avifauna. Forest dependent species (species that require large tracts of mature forest) and assemblages of these species were nested within patches ordered by a gradient of seasonality, and only occupancy of species was nested by area of patches. Thus, forest patches with a shorter dry season include more forest dependent species. PMID:27672498

  8. 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

  9. Molecular characterization of Indonesia avian influenza virus

    Directory of Open Access Journals (Sweden)

    N.L.P.I. Dharmayanti

    2005-06-01

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

  10. It is not just AIV: From avian to swine-origin influenza virus

    Institute of Scientific and Technical Information of China (English)

    GAO George F; SUN YePing

    2010-01-01

    @@ In March and early April 2009, a new swine-origin influenza A (H1N1) virus (S-OIV) emerged in Mexico and the United States.The virus spreads worldwide by human-to-human transmission.Within a few weeks, it reached a pandemic level.The virus is a novel reassorment virus.It contains gene fragments of influenza virus of swine, avian and human emerged from a triple reassortant virus circulating in North American swine.The source triple-reassortant itself comprised genes derived from avian (PB2 and PA), human H3N2 (PB1) and classical swine (HA, NP and NS) lineages.In contrast, the NA and M gene segments have their origin in the Eurasian avian-like swine H1N1 lineage (Figure 1).

  11. Immunogenetics and resistance to avian malaria in Hawaiian honeycreepers (Drepanidinae)

    Science.gov (United States)

    Jarvi, Susan I.; Atkinson, Carter T.; Fleischer, Robert C.

    2001-01-01

    Although a number of factors have contributed to the decline and extinction of Hawai‘i’s endemic terrestrial avifauna, introduced avian malaria (Plasmodium relicturn) is probably the single most important factor preventing recovery of these birds in low-elevation habitats. Continued decline in numbers, fragmentation of populations, and extinction of species that are still relatively common will likely continue without new, aggressive approaches to managing avian disease. Methods of intervention in the disease cycle such as chemotherapy and vaccine development are not feasible because of efficient immune-evasion strategies evolved by the parasite, technical difficulties associated with treating wild avian populations, and increased risk of selection for more virulent strains of the parasite. We are investigating the natural evolution of disease resistance in some low-elevation native bird populations, particularly Hawai‘i ‘Amakihi (Hemignathus virens), to perfect genetic methods for identifying individuals with a greater immunological capacity to survive malarial infection. We are focusing on genetic analyses of the major histocompatibility complex, due to its critical role in both humoral and cell-mediated immune responses. In the parasite, we are evaluating conserved ribosomal genes as well as variable genes encoding cell-surface molecules as a first step in developing a better understanding of the complex interactions between malarial parasites and the avian immune system. A goal is to provide population managers with new criteria for maintaining long-term population stability for threatened species through the development of methods for evaluating and maintaining genetic diversity in small populations at loci important in immunological responsiveness to pathogens.

  12. Evolution of Avian Tumor Viruses

    Science.gov (United States)

    Virus-induced neoplastic diseases of poultry, namely Marek’s disease (MD), induced by a herpesvirus, and the avian leukosis and reticuloendotheliosis induced by retroviruses, can cause significant economic losses from tumor mortality as well as poor performance. Successful control of MD is and has ...

  13. Avian Paramyxovirus: A Brief Review.

    Science.gov (United States)

    Gogoi, P; Ganar, K; Kumar, S

    2017-02-01

    Avian paramyxoviruses (APMVs) have been reported from a wide variety of avian species around the world. Avian paramyxoviruses are economically significant because of the huge mortality and morbidity associated with it. Twelve different serotypes of APMV have been reported till date. Avian paramyxoviruses belong to the family Paramyxoviridae under genus Avulavirus. Newcastle disease virus (APMV-1) is the most characterized members among the APMV serotypes. Complete genome sequence of all twelve APMV serotypes has been published recently. In recent years, APMV-1 has attracted the virologists for its oncolytic activity and its use as a vaccine vector for both animals and humans. The recombinant APMV-based vaccine offers a pertinent choice for the construction of live attenuated vaccine due to its minimum recombination frequency, modular nature of transcription and lack of DNA phase during its replication. Although insufficient data are available regarding other APMV serotypes, our understanding about the APMV biology is expanding rapidly because of the availability of modern molecular biology tools and high-throughput complete genome sequencing.

  14. Subtype Identification of Avian Influenza Virus on DNA Microarray

    Institute of Scientific and Technical Information of China (English)

    WANG Xiu-rong; YU Kang-zhen; DENG Guo-hua; SHI Rui; LIU Li-ling; QIAO Chuan-ling; BAO Hong-mei; KONG Xian-gang; CHEN Hua-lan

    2005-01-01

    We have developed a rapid microarray-based assay for the reliable detection of H5, H7 and H9 subtypes of avian influenza virus (AIV). The strains used in the experiment were A/Goose/Guangdong/1/96 (H5N1), A/African starling/983/79 (H7N1) and A/Turkey/Wiscosin/1/66 (H9N2). The capture DNAs clones which encoding approximate 500-bp avian influenza virus gene fragments obtained by RT-PCR, were spotted on a slide-bound microarray. Cy5-1abeled fluorescent cDNAs,which generated from virus RNA during reverse transcription were hybridized to these capture DNAs. These capture DNAs contained multiple fragments of the hemagglutinin and matrix protein genes of AIV respectively, for subtyping and typing AIV. The arrays were scanned to determine the probe binding sites. The hybridization pattern agreed approximately with the known grid location of each target. The results show that DNA microarray technology provides a useful diagnostic method for AIV.

  15. Ground squirrel shooting and potential lead exposure in breeding avian scavengers

    Science.gov (United States)

    Herring, Garth; Eagles-Smith, Collin A.; Wagner, Mason T.

    2016-01-01

    Recreational ground squirrel shooting is a popular activity throughout the western United States and serves as a tool for managing ground squirrel populations in agricultural regions. Belding’s ground squirrels (Spermophilus beldingi) are routinely shot in California, Nevada, and Oregon across habitats that overlap with breeding avian scavengers. Ground squirrels shot with lead (Pb)-based bullets may pose a risk to avian scavengers if they consume carcasses containing Pb fragments. To assess the potential risk to breeding avian scavengers we developed a model to estimate the number, mass, and distribution of Pb fragments in shot ground squirrels using radiographic images. Eighty percent of shot carcasses contained detectible Pb fragments with an average of 38.6 mg of Pb fragments. Seven percent of all carcasses contained Pb fragment masses exceeding a lethal dose for a model raptor nestling (e.g. American kestrel Falco sparverius). Bullet type did not influence the number of fragments in shot ground squirrels, but did influence the mass of fragments retained. Belding’s ground squirrels shot with .17 Super Mag and unknown ammunition types contained over 28 and 17 times more mass of Pb fragments than those shot with .22 solid and .22 hollow point bullets, respectively. Ground squirrel body mass was positively correlated with both the number and mass of Pb fragments in carcasses, increasing on average by 76% and 56% respectively across the range of carcass masses. Although the mass of Pb retained in ground squirrel carcasses was small relative to the original bullet mass, avian scavenger nestlings that frequently consume shot ground squirrels may be at risk for Pb-induced effects (e.g., physiology, growth, or survival). Using modeling efforts we found that if nestling golden eagles (Aquila chrysaetos), red-tailed hawks (Buteo jamaicensis), and Swainson’s hawks (B. swainsoni) consumed shot ground squirrels proportionately to the nestling’s mass, energy needs

  16. Avian disease at the Salton Sea

    Science.gov (United States)

    Friend, M.

    2002-01-01

    A review of existing records and the scientific literature was conducted for occurrences of avian diseases affecting free-ranging avifauna within the Salton Sea ecosystem. The period for evaluation was 1907 through 1999. Records of the U.S. Department of Agriculture, Bureau of Biological Survey and the scientific literature were the data sources for the period of 1907a??1939. The narrative reports of the U.S. Fish and Wildlife Service's Sonny Bono National Wildlife Refuge Complex and the epizootic database of the U.S. Geological Survey's National Wildlife Health Center were the primary data sources for the remainder of the evaluation. The pattern of avian disease at the Salton Sea has changed greatly over time. Relative to past decades, there was a greater frequency of major outbreaks of avian disease at the Salton Sea during the 1990s than in previous decades, a greater variety of disease agents causing epizootics, and apparent chronic increases in the attrition of birds from disease. Avian mortality was high for about a decade beginning during the mid-1920s, diminished substantially by the 1940s and was at low to moderate levels until the 1990s when it reached the highest levels reported. Avian botulism (Clostridium botulinum type C) was the only major cause of avian disease until 1979 when the first major epizootic of avian cholera (Pasteurella multocidia) was documented. Waterfowl and shorebirds were the primary species affected by avian botulism. A broader spectrum of species have been killed by avian cholera but waterfowl have suffered the greatest losses. Avian cholera reappeared in 1983 and has joined avian botulism as a recurring cause of avian mortality. In 1989, avian salmonellosis (Salmonella typhimurium) was first diagnosed as a major cause of avian disease within the Salton Sea ecosystem and has since reappeared several times, primarily among cattle egrets (Bubulcus ibis). The largest loss from a single epizootic occurred in 1992, when an estimated

  17. Mechanisms in Impact Fragmentation

    OpenAIRE

    Wittel, Falk K.; Carmona, Humberto A.; Kun, Ferenc; Herrmann, Hans J.

    2015-01-01

    The brittle fragmentation of spheres is studied numerically by a 3D Discrete Element Model. Large scale computer simulations are performed with models that consist of agglomerates of many spherical particles, interconnected by beam-truss elements. We focus on a detailed description of the fragmentation process and study several fragmentation mechanisms involved. The evolution of meridional cracks is studied in detail. These cracks are found to initiate in the inside of the specimen with quasi...

  18. DNA fragmentation in apoptosis

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Cleavage of chromosomal DNA into oligonucleosomal size fragments is an integral part of apoptosis. Elegant biochemical work identified the DNA fragmentation factor (DFF) as a major apoptotic endonuclease for DNA fragmentation in vitro. Genetic studies in mice support the importance of DFF in DNA fragmentation and possibly in apoptosis in vivo. Recent work also suggests the existence of additional endonucleases for DNA degradation. Understanding the roles of individual endonucleases in apoptosis, and how they might coordinate to degrade DNA in different tissues during normal development and homeostasis, as well as in various diseased states, will be a major research focus in the near future.

  19. 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

  20. Avian malaria in New Zealand.

    Science.gov (United States)

    Schoener, E R; Banda, M; Howe, L; Castro, I C; Alley, M R

    2014-07-01

    Avian malaria parasites of the genus Plasmodium have the ability to cause morbidity and mortality in naïve hosts, and their impact on the native biodiversity is potentially serious. Over the last decade, avian malaria has aroused increasing interest as an emerging disease in New Zealand with some endemic avian species, such as the endangered mohua (Mohua ochrocephala), thought to be particularly susceptible. To date, avian malaria parasites have been found in 35 different bird species in New Zealand and have been diagnosed as causing death in threatened species such as dotterel (Charadrius obscurus), South Island saddleback (Philesturnus carunculatus carunculatus), mohua, hihi (Notiomystis cincta) and two species of kiwi (Apteryx spp.). Introduced blackbirds (Turdus merula) have been found to be carriers of at least three strains of Plasmodium spp. and because they are very commonly infected, they are likely sources of infection for many of New Zealand's endemic birds. The spread and abundance of introduced and endemic mosquitoes as the result of climate change is also likely to be an important factor in the high prevalence of infection in some regions and at certain times of the year. Although still limited, there is a growing understanding of the ecology and epidemiology of Plasmodium spp. in New Zealand. Molecular biology has played an important part in this process and has markedly improved our understanding of the taxonomy of the genus Plasmodium. This review presents our current state of knowledge, discusses the possible infection and disease outcomes, the implications for host behaviour and reproduction, methods of diagnosis of infection, and the possible vectors for transmission of the disease in New Zealand.

  1. 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.

  2. Gender determination of avian embryo

    Science.gov (United States)

    Daum, Keith A.; Atkinson, David A.

    2002-01-01

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

  3. Avian zoonoses – a review

    Directory of Open Access Journals (Sweden)

    Kozdruń Wojciech

    2015-06-01

    Full Text Available Birds are one of the most interesting and most colourful groups of animals, but they can also be a source of zoonotic factors dangerous for humans. This paper describes the threats to human health from contact with birds. The most vulnerable occupational groups associated with birds are veterinarians, owners of poultry farms, breeders of ornamental birds, zoo personnel, and poultry slaughterhouse workers. Ornithosis is the most dangerous zoonosis of the avian bacterial diseases. Among other hazardous bacterial factors, Salmonella and Campylobacter are responsible for gastrointestinal diseases. Avian influenza is the most dangerous of the viral diseases. It should be noted, however, that avian influenza is a disease of birds, not humans. The recent threat which has appeared is infection with West Nile virus. The results of serological examinations of birds and humans indicate that the virus exists in our ecosystem. Allergic alveolitis connected with the pigeon tick and the Dermanyssus gallinae mite also merits mention. In any case, where people have contact with birds or their droppings and secretions, special precautions should be taken. This way the negative effects of birds on human health can be minimised or eliminated

  4. 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...

  5. String fragmentation; La fragmentation des cordes

    Energy Technology Data Exchange (ETDEWEB)

    Drescher, H.J.; Werner, K. [Laboratoire de Physique Subatomique et des Technologies Associees - SUBATECH, Centre National de la Recherche Scientifique, 44 - Nantes (France)

    1997-10-01

    The classical string model is used in VENUS as a fragmentation model. For the soft domain simple 2-parton strings were sufficient, whereas for higher energies up to LHC, the perturbative regime of the QCD gives additional soft gluons, which are mapped on the string as so called kinks, energy singularities between the leading partons. The kinky string model is chosen to handle fragmentation of these strings by application of the Lorentz invariant area law. The `kinky strings` model, corresponding to the perturbative gluons coming from pQCD, takes into consideration this effect by treating the partons and gluons on the same footing. The decay law is always the Artru-Menessier area law which is the most realistic since it is invariant to the Lorentz and gauge transformations. For low mass strings a manipulation of the rupture point is necessary if the string corresponds already to an elementary particle determined by the mass and the flavor content. By means of the fragmentation model it will be possible to simulate the data from future experiments at LHC and RHIC 3 refs.

  6. Molecular patterns of avian influenza A viruses

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

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

  7. Analysis of Avian Hepatitis E Virus from Chickens, China

    OpenAIRE

    Zhao, Qin; Zhou, En Min; Dong, Shi Wei; Qiu, Hong Kai; Zhang, Lu; Hu, Shou Bin; Zhao, Fei Fei; Jiang, Shi Jin; Sun, Ya Ni

    2010-01-01

    Avian hepatitis E virus (HEV) has been identified in chickens; however, only 4 complete or near-complete genomic sequences have been reported. We found that the near-complete genomic sequence of avian HEV in chickens from China shared the highest identity (98.3%) with avian HEV from Europe and belonged to avian HEV genotype 3.

  8. Analysis of avian hepatitis E virus from chickens, China.

    Science.gov (United States)

    Zhao, Qin; Zhou, En Min; Dong, Shi Wei; Qiu, Hong Kai; Zhang, Lu; Hu, Shou Bin; Zhao, Fei Fei; Jiang, Shi Jin; Sun, Ya Ni

    2010-09-01

    Avian hepatitis E virus (HEV) has been identified in chickens; however, only 4 complete or near-complete genomic sequences have been reported. We found that the near-complete genomic sequence of avian HEV in chickens from China shared the highest identity (98.3%) with avian HEV from Europe and belonged to avian HEV genotype 3.

  9. Landscape matrix mediates occupancy dynamics of Neotropical avian insectivores

    Science.gov (United States)

    Kennedy, Christina M.; Campbell Grant, Evan H.; Neel, Maile C.; Fagan, William F.; Marpa, Peter P.

    2011-01-01

    In addition to patch-level attributes (i.e., area and isolation), the nature of land cover between habitat patches (the matrix) may drive colonization and extinction dynamics in fragmented landscapes. Despite a long-standing recognition of matrix effects in fragmented systems, an understanding of the relative impacts of different types of land cover on patterns and dynamics of species occurrence remains limited. We employed multi-season occupancy models to determine the relative influence of patch area, patch isolation, within-patch vegetation structure, and landscape matrix on occupancy dynamics of nine Neotropical nsectivorous birds in 99 forest patches embedded in four matrix types (agriculture, suburban evelopment, bauxite mining, and forest) in central Jamaica. We found that within-patch vegetation structure and the matrix type between patches were more important than patch area and patch isolation in determining local colonization and local extinction probabilities, and that the effects of patch area, isolation, and vegetation structure on occupancy dynamics tended to be matrix and species dependent. Across the avian community, the landscape matrix influenced local extinction more than local colonization, indicating that extinction processes, rather than movement, likely drive interspecific differences in occupancy dynamics. These findings lend crucial empirical support to the hypothesis that species occupancy dynamics in fragmented systems may depend greatly upon the landscape context.

  10. Embedded Fragments Registry (EFR)

    Data.gov (United States)

    Department of Veterans Affairs — In 2009, the Department of Defense estimated that approximately 40,000 service members who served in OEF/OIF may have embedded fragment wounds as the result of small...

  11. Fragmented Work Stories

    DEFF Research Database (Denmark)

    Humle, Didde Maria; Reff Pedersen, Anne

    2015-01-01

    Following a strand of narrative studies pointing to the living conditions of storytelling and the micro-level implications of working within fragmented narrative perspectives, this article contributes to narrative research on work stories by focusing on how meaning is created from fragmented...... by exploring how different types of fragmentation create meanings. This is done by studying the work stories of job and personnel consultants and by drawing on the results of a narrative, ethnographic study of a consultancy. The analysis demonstrates how work stories are social practices negotiated, retold...... stories. We argue that meaning by story making is not always created by coherence and causality; meaning is created by different types of fragmentation: discontinuities, tensions and editing. The objective of this article is to develop and advance antenarrative practice analysis of work stories...

  12. Fragmentation in Biaxial Tension

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, G H; Archbold, G C; Hurricane, O A; Miller, P L

    2006-06-13

    We have carried out an experiment that places a ductile stainless steel in a state of biaxial tension at a high rate of strain. The loading of the ductile metal spherical cap is performed by the detonation of a high explosive layer with a conforming geometry to expand the metal radially outwards. Simulations of the loading and expansion of the metal predict strain rates that compare well with experimental observations. A high percentage of the HE loaded material was recovered through a soft capture process and characterization of the recovered fragments provided high quality data, including uniform strain prior to failure and fragment size. These data were used with a modified fragmentation model to determine a fragmentation energy.

  13. Fragmentation Main Model

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The fragmentation model combines patch size and patch continuity with diversity of vegetation types per patch and rarity of vegetation types per patch. A patch was...

  14. Physiologically driven avian vocal synthesizer

    Science.gov (United States)

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

    2010-03-01

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

  15. Thermodynamics of fragment binding.

    Science.gov (United States)

    Ferenczy, György G; Keserű, György M

    2012-04-23

    The ligand binding pockets of proteins have preponderance of hydrophobic amino acids and are typically within the apolar interior of the protein; nevertheless, they are able to bind low complexity, polar, water-soluble fragments. In order to understand this phenomenon, we analyzed high resolution X-ray data of protein-ligand complexes from the Protein Data Bank and found that fragments bind to proteins with two near optimal geometry H-bonds on average. The linear extent of the fragment binding site was found not to be larger than 10 Å, and the H-bonding region was found to be restricted to about 5 Å on average. The number of conserved H-bonds in proteins cocrystallized with multiple different fragments is also near to 2. These fragment binding sites that are able to form limited number of strong H-bonds in a hydrophobic environment are identified as hot spots. An estimate of the free-energy gain of H-bond formation versus apolar desolvation supports that fragment sized compounds need H-bonds to achieve detectable binding. This suggests that fragment binding is mostly enthalpic that is in line with their observed binding thermodynamics documented in Isothermal Titration Calorimetry (ITC) data sets and gives a thermodynamic rationale for fragment based approaches. The binding of larger compounds tends to more rely on apolar desolvation with a corresponding increase of the entropy content of their binding free-energy. These findings explain the reported size-dependence of maximal available affinity and ligand efficiency both behaving differently in the small molecule region featured by strong H-bond formation and in the larger molecule region featured by apolar desolvation.

  16. The Development of Pathogenicity of Avian Influenza Virus Isolated from Indonesia

    Directory of Open Access Journals (Sweden)

    Michael Haryadi Wibowo

    2015-11-01

    Full Text Available Highly pathogenic avian infl uenza outbreak in Indonesia has been reported in various poultry due toH5N1 subtype. The presence of multiple basic amino acids within the cleavage site of HA glycoprotein hasbeen identifi ed to be associated with the pathogenicity of avian infl uenza virus. The study was retrospectivestudy which was designed to characterize the cleavage site and fusion site region of haemagglutinin gene ofAIV isolated from various poultry in 2003 to 2013. Isolation, Identifi cation and propagation were carried outto collect viral stock. For virus detection, reverse transcriptase PCR (RT-PCR method on H5 and N1 genefragment was performed. All of RT-PCR HA gene positive products were sequenced for further nucleotideanalysis and to determine the nucleotide composition at the targeted fragment. The results are all AIV isolateswere identifi ed as H5N1 subtype. The sequence analyses revealed some motives of basic amino acid motivethat were classifi ed as highly pathogenic avian infl uenza virus. Further analyses on fusion domain of all AIVisolated during the period 2003 to 2013 showed conserved amino acid.Keywords: avian infl uenza, haemagglutinin, cleavage site, basic amino acid, fusion site

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

    Science.gov (United States)

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

    1996-12-01

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

  18. 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.

  19. Long-term demographic consequences of habitat fragmentation to a tropical understory bird community

    Science.gov (United States)

    Korfanta, N.M.; Newmark, W.D.; Kauffman, M.J.

    2012-01-01

    Tropical deforestation continues to cause population declines and local extinctions in centers of avian diversity and endemism. Although local species extinctions stem from reductions in demographic rates, little is known about how habitat fragmentation influences survival of tropical bird populations or the relative importance of survival and fecundity in ultimately shaping communities. We analyzed 22 years of mark-recapture data to assess how fragmentation influenced apparent survival, recruitment, and realized population growth rate within 22 forest understory bird species in the Usambara Mountains, Tanzania. This represents the first such effort, in either tropical or temperate systems, to characterize the effect of deforestation on avian survival across such a broad suite of species. Long-term demographic analysis of this suite of species experiencing the same fragmented environment revealed considerable variability in species' responses to fragmentation, in addition to general patterns that emerged from comparison among species. Across the understory bird community as a whole, we found significantly lower apparent survival and realized population growth rate in small fragments relative to large, demonstrating fragmentation effects to demographic rates long after habitat loss. Demographic rates were depressed across five feeding guilds, suggesting that fragmentation sensitivity was not limited to insectivores. Seniority analyses, together with a positive effect of fragmentation on recruitment, indicated that depressed apparent survival was the primary driver of population declines and observed extinctions. We also found a landscape effect, with lower vital rates in one mountain range relative to another, suggesting that fragmentation effects may add to other large-scale drivers of population decline. Overall, realized population growth rate (λ) estimates were < 1 for most species, suggesting that future population persistence even within large forest

  20. Emerging and reemerging diseases of avian wildlife

    Science.gov (United States)

    Pello, Susan J.; Olsen, Glenn H.

    2013-01-01

    Of the many important avian wildlife diseases, aspergillosis, West Nile virus, avipoxvirus, Wellfleet Bay virus, avian influenza, and inclusion body disease of cranes are covered in this article. Wellfleet Bay virus, first identified in 2010, is considered an emerging disease. Avian influenza and West Nile virus have recently been in the public eye because of their zoonotic potential and links to wildlife. Several diseases labeled as reemerging are included because of recent outbreaks or, more importantly, recent research in areas such as genomics, which shed light on the mechanisms whereby these adaptable, persistent pathogens continue to spread and thrive.

  1. AVIAN POXVIRUS INFECTION IN A FLAMINGO (PHOENICOPTERUS RUBER) OF THE LISBON ZOO.

    Science.gov (United States)

    Henriques, Ana M; Fagulha, Teresa; Duarte, Margarida; Ramos, Fernanda; Barros, Sílvia C; Luís, Tiago; Bernardino, Rui; Fernandes, Teresa L; Lapão, Narciso; da Silva, José Ferreira; Fevereiro, Miguel

    2016-03-01

    Avian poxviruses (APV) are very large viruses spread worldwide in a variety of hosts. They are responsible for a disease usually referred to as pox, mainly characterized by nodular lesions on feather-free regions of the body. On May 2010, a young American flamingo (Phoenicopterus ruber) of the Lisbon Zoo (Portugal) developed a nodular lesion suggestive of poxvirus infection on its right foot. Avipoxvirus was isolated from the lesion and a fragment of the P4b-encoding gene was amplified by polymerase chain reaction. The nucleotide sequence of the amplicon was determined and analyzed. A close relationship (100% identity) was observed between the flamingo poxvirus and isolates from great bustard (Hungary 2005), house sparrow (Morocco 2009), MacQueen's bustard (Morocco 2011), and Houbara bustard (Morocco 2010 and 2011), suggesting interspecies transmission as a possible source of infection. To strengthen the investigation, the 5' and 3' ends of genes cnpv186 and cnpv 187, respectively, were also analyzed. The cnpv186-187 fragment exhibited 100% identity with MacQueen's bustard and Houbara bustard isolates, both from Morocco 2011. Phylogenetic analyses based in both fragments grouped the flamingo isolate consistently within clade B2 of canarypox. However, the phylogenetic relationships among the different representatives of avian poxviruses were more comprehensive in the tree based on the concatenated coding sequences of the cnpv186-187 fragment, rather than on the P4b-coding gene. The clearer displacement and distribution of the isolates regarding their host species in this last tree suggests the potential usefulness of this genomic region to refine avian poxvirus classification.

  2. Molecular detection of avian pox virus from nodular skin and mucosal fibrinonecrotic lesions of Iranian backyard poultry.

    Science.gov (United States)

    Gholami-Ahangaran, Majid; Zia-Jahromi, Noosha; Namjoo, Abdolrasul

    2014-02-01

    In recent years, some outbreaks of skin lesions suspected to be avian pox were observed in the backyard poultry in different parts of western areas in Iran. Consequently, 328 backyard poultries with suspected signs of avian pox virus infection were sampled. All birds showed nodular lesions on unfeathered head skin and/or fibronecrotic lesions on mucus membrane of the oral cavity and upper respiratory tract. For histopathological analysis, the sections of tissue samples from cutaneous lesions of examined birds were stained with H&E method. For PCR, after DNA extraction a 578-bp fragment of avian pox virus from 4b core protein gene was amplified. Results showed 217 and 265 out of 328 (66.1 and 80.7%, respectively) samples were positive for avian pox virus on histopathological and PCR examination, respectively. In this study, the samples that had intracytoplasmic inclusion bodies on pathologic examination were PCR positive. This study revealed that PCR is a valuable tool for identification of an avian pox virus and that the frequency of pox infection in backyard poultry in western areas of Iran is high.

  3. Fluctuations of fragment observables

    CERN Document Server

    Gulminelli, F

    2006-01-01

    This contribution presents a review of our present theoretical as well as experimental knowledge of different fluctuation observables relevant to nuclear multifragmentation. The possible connection between the presence of a fluctuation peak and the occurrence of a phase transition or a critical phenomenon is critically analyzed. Many different phenomena can lead both to the creation and to the suppression of a fluctuation peak. In particular, the role of constraints due to conservation laws and to data sorting is shown to be essential. From the experimental point of view, a comparison of the available fragmentation data reveals that there is a good agreement between different data sets of basic fluctuation observables, if the fragmenting source is of comparable size. This compatibility suggests that the fragmentation process is largely independent of the reaction mechanism (central versus peripheral collisions, symmetric versus asymmetric systems, light ions versus heavy ion induced reactions). Configurationa...

  4. Fragments of Time

    DEFF Research Database (Denmark)

    Christiansen, Steen Ledet

    Time travel films necessarily fragment linear narratives, as scenes are revisited with differences from the first time we saw it. Popular films such as Back to the Future mine comedy from these visitations, but there are many different approaches. One extreme is Chris Marker's La Jetée - a film...... made almost completely of still images, recounting the end of the world. These stills can be viewed as fragments that have survived the end of the world and now provide the only access to the events that occured. Shane Carruth's Primer has a different approach to time travel, the narrative diegesis...

  5. IMPACT fragmentation model developments

    Science.gov (United States)

    Sorge, Marlon E.; Mains, Deanna L.

    2016-09-01

    The IMPACT fragmentation model has been used by The Aerospace Corporation for more than 25 years to analyze orbital altitude explosions and hypervelocity collisions. The model is semi-empirical, combining mass, energy and momentum conservation laws with empirically derived relationships for fragment characteristics such as number, mass, area-to-mass ratio, and spreading velocity as well as event energy distribution. Model results are used for several types of analysis including assessment of short-term risks to satellites from orbital altitude fragmentations, prediction of the long-term evolution of the orbital debris environment and forensic assessments of breakup events. A new version of IMPACT, version 6, has been completed and incorporates a number of advancements enabled by a multi-year long effort to characterize more than 11,000 debris fragments from more than three dozen historical on-orbit breakup events. These events involved a wide range of causes, energies, and fragmenting objects. Special focus was placed on the explosion model, as the majority of events examined were explosions. Revisions were made to the mass distribution used for explosion events, increasing the number of smaller fragments generated. The algorithm for modeling upper stage large fragment generation was updated. A momentum conserving asymmetric spreading velocity distribution algorithm was implemented to better represent sub-catastrophic events. An approach was developed for modeling sub-catastrophic explosions, those where the majority of the parent object remains intact, based on estimated event energy. Finally, significant modifications were made to the area-to-mass ratio distribution to incorporate the tendencies of different materials to fragment into different shapes. This ability enabled better matches between the observed area-to-mass ratios and those generated by the model. It also opened up additional possibilities for post-event analysis of breakups. The paper will discuss

  6. Effects of habitat on avian productivity in abandoned pecan orchards in southern Georgia

    Science.gov (United States)

    Patnode, K.A.; White, D.H.

    1992-01-01

    Daily survival rates (DSRs) of nests, eggs and nestlings were determined for Mourning Doves (Zenaida macroura), Northern Cardinals (Cardinalis cardinalis), Brown Thrashers (Toxostoma rufum) and Northern Mockingbirds (Mimus polyglottos) occupying abandoned pecan orchards in a highly fragmented and intensively farmed area of southern Georgia. The effects of nest placement parameters, seasonal factors and habitat disruptions on DSRs for all species combined were statistically analyzed. Egg and nestling DSRs varied significantly by month of nesting, percent cover, vegetative form and position of nest in substrate. Causes of nest failure (no fledglings produced) in order of decreasing importance were predation by small mammals/snakes, avian predation, predation by large mammals, and abandonment. Results provide further evidence that the importance of nest placement and habitat disruptions in nesting success is influenced by foraging strategies of the predator community. Site-specific predator/habitat complexes may be a more appropriate criterion than habitat conditions alone for evaluating avian nesting habitat

  7. PCR-based detection of an emerging avian pneumovirus in US turkey flocks.

    Science.gov (United States)

    Dar, A M; Tune, K; Munir, S; Panigrahy, B; Goyal, S M; Kapur, V

    2001-05-01

    Avian pneumovirus (APV) or turkey rhinotracheitis virus (TRTV) is an important respiratory pathogen of domesticated poultry in many countries in Europe, Africa, and Asia. Until recently, the United States was considered free of APV. In late 1996, an atypical upper respiratory tract infection appeared in turkey flocks in Colorado and shortly thereafter in turkey flocks in Minnesota. An avian pneumovirus (APV-US) that was serologically distinct from the previously described TRTV was isolated as the primary cause of the new syndrome. The nucleotide sequence of a fragment of the APV-US fusion gene was determined and used to develop a polymerase chain reaction-based assay that specifically detects APV-US viral nucleic acid sequences in RNA extracts of tracheal swabs and turbinate homogenates. The assay is highly sensitive in that it can detect <0.01 TCID50 of APV. The availability of this assay enables the rapid and accurate determination of APV-US in infected poultry flocks.

  8. Towards the routine application of nucleic acid technology for avian disease diagnosis.

    Science.gov (United States)

    Cavanagh, D; Mawditt, K; Shaw, K; Britton, P; Naylor, C

    1997-01-01

    The use of nucleic acid technology (polymerase chain reaction, probing, restriction fragment analysis and nucleotide sequencing) in the study of avian diseases has largely been confined to fundamental analysis and retrospective studies. More recently these approaches have been applied to diagnosis and what one might call real-time epidemiological studies on chickens and turkeys. At the heart of these approaches is the identification and characterisation of pathogens based on their genetic material, RNA or DNA. Among the objectives has been the detection of pathogens quickly combined with the simultaneous identification of serotype, subtype or genotype. Nucleic acid sequencing also gives a degree of characterisation unmatched by other approaches. In this paper we describe the use of nucleic acid technology for the diagnosis and epidemiology of infectious bronchitis virus, turkey rhinotracheitis virus (avian pneumovirus) and Newcastle disease virus.

  9. Montana 2006 Avian Influenza Surveillance Project Report

    Data.gov (United States)

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

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

    Data.gov (United States)

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

  11. Avian models in teratology and developmental toxicology.

    Science.gov (United States)

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

    2012-01-01

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

  12. Avian protection plan : Lostwood National Wildlife Refuge

    Data.gov (United States)

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

  13. Immunizing Canada geese against avian cholera

    Science.gov (United States)

    Price, J.I.

    1985-01-01

    A small flock of captive giant Canada geese were vaccinated with the experimental bac- terin in Nebraska to test its efficacy under field conditions. Only 2 of 157 vaccinates died from avian cholera during an annual spring die-off.

  14. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into ... Virus (CVV) for a Highly Pathogenic Avian Influenza (Bird Flu) Virus ” for more information on this process. ...

  15. Cell killing by avian leukosis viruses.

    OpenAIRE

    Weller, S K; Temin, H M

    1981-01-01

    Infection of chicken cells with a cytopathic avian leukosis virus resulted in the detachment of killed cells from the culture dish. The detached, dead cells contained more unintegrated viral DNA than the attached cells. These results confirm the hypothesis that cell killing after infection with a cytopathic avian leukosis virus is associated with accumulation of large amounts of unintegrated viral DNA. No accumulation of large amounts of integrated viral DNA was found in cells infected with c...

  16. Report of the Avian Development Working Group

    Science.gov (United States)

    Fallon, J. F.

    1985-01-01

    The anteroposterior axis of the avian embryo is established before it is laid. Baer's rule states that the cephalic end of the avian embryo will be away from the observer when the pointed end of the shell is on the observer's right. There are experimental data available which indicate gravity has a role in the establishment of the anteroposterior axis while the egg is in the uterus; this results in Baer's rule. The influence of gravity on egg development is studied.

  17. Picking Up (On) Fragments

    NARCIS (Netherlands)

    Ellis, Phil

    2015-01-01

    abstractThis article discusses the implications for archival and media archaeological research and reenactment artwork relating to a recent arts practice project: reenacttv: 30 lines / 60 seconds. It proposes that archival material is unstable but has traces and fragments that are full of creative p

  18. Fragments of the Past

    Directory of Open Access Journals (Sweden)

    Peter Szende

    2016-10-01

    Full Text Available With travel being made more accessible throughout the decades, the hospitality industry constantly evolved their practices as society and technology progressed. Hotels looked for news ways up service their customers, which led to the invention of the Servidor in 1918. Once revolutionary innovations have gone extinct, merely becoming fragments of the past.

  19. 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.

  20. 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

  1. 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.

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

    Data.gov (United States)

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

  3. Determination and analysis of the complete genomic sequence of avian hepatitis E virus (avian HEV) and attempts to infect rhesus monkeys with avian HEV.

    Science.gov (United States)

    Huang, F F; Sun, Z F; Emerson, S U; Purcell, R H; Shivaprasad, H L; Pierson, F W; Toth, T E; Meng, X J

    2004-06-01

    Avian hepatitis E virus (avian HEV), recently identified from a chicken with hepatitis-splenomegaly syndrome in the United States, is genetically and antigenically related to human and swine HEVs. In this study, sequencing of the genome was completed and an attempt was made to infect rhesus monkeys with avian HEV. The full-length genome of avian HEV, excluding the poly(A) tail, is 6654 bp in length, which is about 600 bp shorter than that of human and swine HEVs. Similar to human and swine HEV genomes, the avian HEV genome consists of a short 5' non-coding region (NCR) followed by three partially overlapping open reading frames (ORFs) and a 3'NCR. Avian HEV shares about 50 % nucleotide sequence identity over the complete genome, 48-51 % identity in ORF1, 46-48 % identity in ORF2 and only 29-34 % identity in ORF3 with human and swine HEV strains. Significant genetic variations such as deletions and insertions, particularly in ORF1 of avian HEV, were observed. However, motifs in the putative functional domains of ORF1, such as the helicase and methyltransferase, were relatively conserved between avian HEV and mammalian HEVs, supporting the conclusion that avian HEV is a member of the genus Hepevirus. Phylogenetic analysis revealed that avian HEV represents a branch distinct from human and swine HEVs. Swine HEV infects non-human primates and possibly humans and thus may be zoonotic. An attempt was made to determine whether avian HEV also infects across species by experimentally inoculating two rhesus monkeys with avian HEV. Evidence of virus infection was not observed in the inoculated monkeys as there was no seroconversion, viraemia, faecal virus shedding or serum liver enzyme elevation. The results from this study confirmed that avian HEV is related to, but distinct from, human and swine HEVs; however, unlike swine HEV, avian HEV is probably not transmissible to non-human primates.

  4. CFTR mediated chloride secretion in the avian renal proximal tubule.

    Science.gov (United States)

    Laverty, Gary; Anttila, Ashley; Carty, Jenava; Reddy, Varudhini; Yum, Jamie; Arnason, Sighvatur S

    2012-01-01

    In primary cell cultures of the avian (Gallus gallus) renal proximal tubule parathyroid hormone and cAMP activation generate a Cl(-)-dependent short circuit current (I(SC)) response, consistent with net transepithelial Cl(-) secretion. In this study we investigated the expression and physiological function of the Na-K-2Cl (NKCC) transporter and CFTR chloride channel, both associated with Cl(-) secretion in a variety of tissues, in these proximal tubule cells. Using both RT-PCR and immunoblotting approaches, we showed that NKCC and CFTR are expressed, both in proximal tubule primary cultures and in a proximal tubule fraction of non-cultured (native tissue) fragments. We also used electrophysiological methods to assess the functional contribution of NKCC and CFTR to forskolin-activated I(SC) responses in filter grown cultured monolayers. Bumetanide (10 μM), a specific blocker of NKCC, inhibited forskolin activated I(SC) by about 40%, suggesting that basolateral uptake of Cl(-) is partially mediated by NKCC transport. In monolayers permeabilized on the basolateral side with nystatin, forskolin activated an apical Cl(-) conductance, manifested as bidirectional diffusion currents in the presence of oppositely directed Cl(-) gradients. Under these conditions the apical conductance appeared to show some bias towards apical-to-basolateral Cl(-) current. Two selective CFTR blockers, CFTR Inhibitor 172 and GlyH-101 (both at 20 μM) inhibited the forskolin activated diffusion currents by 38-68%, with GlyH-101 having a greater effect. These data support the conclusion that avian renal proximal tubules utilize an apical CFTR Cl(-) channel to mediate cAMP-activated Cl(-) secretion.

  5. 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.

  6. 9 CFR 113.325 - Avian Encephalomyelitis Vaccine.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Avian Encephalomyelitis Vaccine. 113... REQUIREMENTS Live Virus Vaccines § 113.325 Avian Encephalomyelitis Vaccine. Avian Encephalomyelitis Vaccine... vaccine production. All serials shall be prepared from the first through the fifth passage from the...

  7. Heavy meson fragmentation at LHC

    Directory of Open Access Journals (Sweden)

    M. A. Gomshi Nobary

    2003-06-01

    Full Text Available   Large Hadron Collider (LHC at CERN will provide excellent opportunity to study the production and decay of heavy mesons and baryons with high statistics. We aim at the heavy mesons in this work and calculate their fragmentation functions consistent with this machine and present their total fragmentation probabilities and average fragmentation parameters.

  8. Picking Up (On Fragments

    Directory of Open Access Journals (Sweden)

    Phil Ellis

    2015-09-01

    Full Text Available This article discusses the implications for archival and media archaeological research and reenactment artwork relating to a recent arts practice project: reenacttv: 30 lines / 60 seconds. It proposes that archival material is unstable but has traces and fragments that are full of creative potential to re-think and re-examine past media historical events through a media archaeological approach to reenactment. The article contains images and links to videos from the final reenactment artworks as well as from rehearsals in Vienna and Bradford.

  9. An Archeology of Fragments

    Directory of Open Access Journals (Sweden)

    Gerald L. Bruns

    2014-10-01

    Full Text Available This is a short (fragmentary history of fragmentary writing from the German Romantics (F. W. Schlegel, Friedrich Hölderlin to modern and contemporary concrete or visual poetry. Such writing is (often deliberately a critique of the logic of subsumption that tries to assimilate whatever is singular and irreducible into totalities of various categorical or systematic sorts. Arguably, the fragment (parataxis is the distinctive feature of literary Modernism, which is a rejection, not of what precedes it, but of what Max Weber called “the rationalization of the world” (or Modernity whose aim is to keep everything, including all that is written, under surveillance and control.

  10. Evidence of genotypes 1 and 3 of avian hepatitis E virus in wild birds.

    Science.gov (United States)

    Zhang, Xinquan; Bilic, Ivana; Troxler, Salome; Hess, Michael

    2017-01-15

    Although the presence of four genotypes of avian hepatitis E virus (HEV) in chickens has been demonstrated, its natural host range is still barely known. In this study, swab samples from 626 wild birds originating from 62 bird species were investigated for HEV detection by molecular methods. The aim was to explore the cross-species infection of avian HEV and to compare the genetic diversity between strains infecting chicken and wild birds. In total, 8 positive samples from 4 different bird species (song thrush, little owl, feral pigeon and common buzzard) were identified and further confirmed by partial sequencing of ORF3. Based on a 237bp fragment of the capsid gene retrieved from 5 samples, phylogenetic analysis revealed the presence of avian HEV genotypes 1 and 3 in wild birds. The wild bird isolates shared 82.7-84.8% and 85.7-100% nucleotide sequence identity, respectively, to chicken isolates from the corresponding genotype. For two of the genotype 1 samples (14-2901 and 14-2906), from feral pigeons, genotype assignment could be also confirmed by phylogenetic analysis based on partial nucleotide sequence of the helicase gene. For the first time, the appearance of genotype 1 in Europe was detected, which together with close genetic relationship between HEVs present in chickens and wild birds indicates cross-species transmission.

  11. Using amplified fragment length polymorphism analysis to differentiate isolates of Pasteurella multocida serotype 1

    Science.gov (United States)

    Blehert, D.S.; Jefferson, K.L.; Heisey, D.M.; Samuel, M.D.; Berlowski, B.M.; Shadduck, D.J.

    2008-01-01

    Avian cholera, an infectious disease caused by the bacterium Pasteurella multocida, kills thousands of North American wild waterfowl annually. Pasteurella multocida serotype 1 isolates cultured during a laboratory challenge study of Mallards (Anas platyrhynchos) and collected from wild birds and environmental samples during avian cholera outbreaks were characterized using amplified fragment length polymorphism (AFLP) analysis, a whole-genome DNA fingerprinting technique. Comparison of the AFLP profiles of 53 isolates from the laboratory challenge demonstrated that P. multocida underwent genetic changes during a 3-mo period. Analysis of 120 P. multocida serotype 1 isolates collected from wild birds and environmental samples revealed that isolates were distinguishable from one another based on regional and temporal genetic characteristics. Thus, AFLP analysis had the ability to distinguish P. multocida isolates of the same serotype by detecting spatiotemporal genetic changes and provides a tool to advance the study of avian cholera epidemiology. Further application of AFLP technology to the examination of wild bird avian cholera outbreaks may facilitate more effective management of this disease by providing the potential to investigate correlations between virulence and P. multocida genotypes, to identify affiliations between bird species and bacterial genotypes, and to elucidate the role of specific bird species in disease transmission. ?? Wildlife Disease Association 2008.

  12. Thermal emissivity of avian eggshells.

    Science.gov (United States)

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

    2016-04-01

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

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

    Directory of Open Access Journals (Sweden)

    V Demircan

    2009-09-01

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

  14. Detection and subtyping (H5 and H7) of avian type A influenza virus by reverse transcription-PCR and PCR-ELISA

    DEFF Research Database (Denmark)

    Munch, M.; Nielsen, L.P.; Handberg, Kurt;

    2001-01-01

    Avian influenza virus infections are a major cause of morbidity and rapid identification of the virus has important clinical, economical and epidemiological implications. We have developed a one-tube Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) for the rapid diagnosis of avian influenza...... A. A panel of reference influenza strains from various hosts including avian species, human, swine and horse were evaluated in a one tube RT-PCR using primers designed for the amplification of a 218 bp fragment of the NP gene. The PCR products were detected by PCR-ELISA by use of an internal...... catching probe confirming the NP influenza A origin. The PCR-ELISA was about 100 times more sensitive than detection of PCR products by agarose gel electrophoresis. RT-PCR and detection by PCR-ELISA is comparable in sensitivity to virus propagation in eggs. We also designed primers for the detection...

  15. The Serendipity of Fragmentation

    DEFF Research Database (Denmark)

    Leixnering, Stephan; Meyer, Renate E.

    Reform approaches in the public sector led to significant changes in the sector’s design. Especially NPM-inspired reform measures which had largely aimed at organizational disaggregation created pluriform landscapes of public sector organizations (PSOs). Following a core public governance principle......, it was the central government’s task to coordinate, steer and control the newly emerged decentralized organizations. This raises questions about the overall design of the public sector at present. Our paper engages with the prevalent public governance phenomenon of fragmentation from a design perspective in order...... insights in how structures and relations were formally designed. Second, we interviewed top officials and executives who performed key tasks in the coordination and management of the city’s autonomous units....

  16. Stone fragmentation by ultrasound

    Indian Academy of Sciences (India)

    S K Shrivastava; Kailash

    2004-08-01

    The presence of kidney stone in the kidney causes discomfort to patients. Hence, removal of such stones is important which is commonly done these days, non-destructively, with lithotripters without surgery. Commercially, lithotripters like extra-corporeal shock wave lithotripters (ESWL) made by Siemens etc are in routine use. These methods are very cumbersome and expensive. Treatment of the patients also takes comparatively more time because of more number of sittings. Some delicate nerves and fibres in the surrounding areas of the stones present in the kidney are also damaged by high ultrasonic intensity used in such systems. In the present work, enhancement of the kidney stone fragmentation by using ultrasound is studied. The cavitation bubbles are found to implode faster, with more disintegration efficiency of the lithotripters, which give better treatment to the patients.

  17. Integration and Validation of Avian Radars (IVAR)

    Science.gov (United States)

    2011-08-01

    operations; 1-year visual census; multiple eBirdRad radars; fiber- optic wired LAN (planned) NAS Patuxent River, MD X B X Medium-sized air station...introduced a multibeam avian radar antenna that purports to double the beam width (from 4° to 8°), while at the same time increasing the precision of the

  18. Avian influenza virus and Newcastle disease virus

    Science.gov (United States)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) severely impact poultry egg production. Decreased egg yield and hatchability, as well as misshapen eggs, are often observed during infection with AIV and NDV, even with low-virulence strains or in vaccinated flocks. Data suggest that in...

  19. 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...

  20. Measuring steroid hormones in avian eggs

    NARCIS (Netherlands)

    Von Engelhardt, N; Groothuis, TGG; 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 attention

  1. 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...

  2. 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...

  3. Measuring Steroid Hormones in Avian Eggs

    NARCIS (Netherlands)

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

    2005-01-01

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

  4. Website for avian flu information and bioinformatics

    Institute of Scientific and Technical Information of China (English)

    GAO; George; Fu

    2009-01-01

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

  5. [Avian influenza and oseltamivir; a retrospective view

    NARCIS (Netherlands)

    Galama, J.M.D.

    2003-01-01

    The outbreak of avian influenza A due to an H7N7 virus in Dutch poultry farms turned out to have public-health effects for those who were involved in the management of the epidemic and who were thus extensively exposed to contaminated excreta and dust. An outbreak-management team (OMT) of experts in

  6. Website for avian flu information and bioinformatics

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

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

  7. CONTROL OF FRAGMENTATION BY BLASTING

    Directory of Open Access Journals (Sweden)

    Branko Božić

    1998-12-01

    Full Text Available The degree of fragmentation influences the economy of the excavation operations. Characteristics of blasted rock such as fragment size, volume and mass are fundamental variables effecting the economics of a mining operation and are in effect the basis for evaluating the quality of a blast. The properties of fragmentation, such as size and shape, are very important information for the optimization of production. Three factors control the fragment size distribution: the rock structure, the quantity of explosive and its distribution within the rock mass. Over the last decade there have been considerable advances in our ability to measure and analyze blasting performance. These can now be combined with the continuing growth in computing power to develop a more effective description of rock fragmentation for use by future blasting practitioners. The paper describes a view of the fragmentation problem by blasting and the need for a new generation of engineering tools to guide the design and implementation of blasting operations.

  8. Thermodynamical string fragmentation

    Science.gov (United States)

    Fischer, Nadine; Sjöstrand, Torbjörn

    2017-01-01

    The observation of heavy-ion-like behaviour in pp collisions at the LHC suggests that more physics mechanisms are at play than traditionally assumed. The introduction e.g. of quark-gluon plasma or colour rope formation can describe several of the observations, but as of yet there is no established paradigm. In this article we study a few possible modifications to the Pythia event generator, which describes a wealth of data but fails for a number of recent observations. Firstly, we present a new model for generating the transverse momentum of hadrons during the string fragmentation process, inspired by thermodynamics, where heavier hadrons naturally are suppressed in rate but obtain a higher average transverse momentum. Secondly, close-packing of strings is taken into account by making the temperature or string tension environment-dependent. Thirdly, a simple model for hadron rescattering is added. The effect of these modifications is studied, individually and taken together, and compared with data mainly from the LHC. While some improvements can be noted, it turns out to be nontrivial to obtain effects as big as required, and further work is called for.

  9. Thermodynamical String Fragmentation

    CERN Document Server

    Fischer, Nadine

    2016-01-01

    The observation of heavy-ion-like behaviour in pp collisions at the LHC suggests that more physics mechanisms are at play than traditionally assumed. The introduction e.g. of quark-gluon plasma or colour rope formation can describe several of the observations, but as of yet there is no established paradigm. In this article we study a few possible modifications to the Pythia event generator, which describes a wealth of data but fails for a number of recent observations. Firstly, we present a new model for generating the transverse momentum of hadrons during the string fragmentation process, inspired by thermodynamics, where heavier hadrons naturally are suppressed in rate but obtain a higher average transverse momentum. Secondly, close-packing of strings is taken into account by making the temperature or string tension environment-dependent. Thirdly, a simple model for hadron rescattering is added. The effect of these modifications is studied, individually and taken together, and compared with data mainly from...

  10. Fragmentation Considered Poisonous

    CERN Document Server

    Herzberg, Amir

    2012-01-01

    We present practical poisoning and name-server block- ing attacks on standard DNS resolvers, by off-path, spoofing adversaries. Our attacks exploit large DNS responses that cause IP fragmentation; such long re- sponses are increasingly common, mainly due to the use of DNSSEC. In common scenarios, where DNSSEC is partially or incorrectly deployed, our poisoning attacks allow 'com- plete' domain hijacking. When DNSSEC is fully de- ployed, attacker can force use of fake name server; we show exploits of this allowing off-path traffic analy- sis and covert channel. When using NSEC3 opt-out, attacker can also create fake subdomains, circumvent- ing same origin restrictions. Our attacks circumvent resolver-side defenses, e.g., port randomisation, IP ran- domisation and query randomisation. The (new) name server (NS) blocking attacks force re- solver to use specific name server. This attack allows Degradation of Service, traffic-analysis and covert chan- nel, and also facilitates DNS poisoning. We validated the attac...

  11. [Isolation and identification of avian leukosis virus-B from layer chickens infected with avian leukosis virus-J].

    Science.gov (United States)

    Liu, Gong-Zhen; Zhang, Hong-Hai; Liu, Qing; Qiu, Bo; Wang, Feng; Wang, Xiao-Wei; Chen, Hong-Bo; Cheng, Zi-Qiang

    2009-11-01

    Two strains of Avian leukosis virus subgroup B (ALV-B) were isolated for the first time in China Hy-line White on the cultured DF-1 cells which were inoculated tissue samples from by an ELISA assay, a histopathology examination and a PCR-based diagnosis. The results from the ELISA assay indicated that the positive rate of serum antibodies to ALV-B and ALV-J virus were 16.3% (15/92) and 13% (12/92), respectively. The histopathological examination indicated that two types of tumor cells existed at same focus in liver and spleen, which mainly were myelocytoma cells and lymphosarcoma cells. The PCR-based diagnosis were performed as follows: the cellular DNA was extracted from the inoculated DF-1 cells; the specific fragments of 1100 bp and 924 bp were obtained by a PCR system with the diagnostic primers of ALV-B and ALV-J; and the PCR results for ALV-A, MDV and REV were all negative. Then, the amplified fragments of the two ALV-B stains were partially sequenced and shown an identity of 92.8%,94.7% with the prototype strain of ALV-B (RSV Schmidt-ruppin B). The identities of two ALV-J strains with the prototype strain HPRS-103 at 96.9%, 91.5%; The identities of two ALV-J strains with the American prototype strain at 85.9%, 81.5%. Our study had shown that ALV-B was isolated for the first time from the ALV-J infected commercial layer flocks in China. It also indicated that the chance of genetic recombination among various subgroups of ALV was increased.

  12. An Algebra for Program Fragments

    DEFF Research Database (Denmark)

    Kristensen, Bent Bruun; Madsen, Ole Lehrmann; Møller-Pedersen, Birger

    1985-01-01

    Program fragments are described either by strings in the concrete syntax or by constructor applications in the abstract syntax. By defining conversions between these forms, both may be intermixed. Program fragments are constructed by terminal and nonterminal symbols from the grammar and by variab...

  13. Complete axiomatizations for XPath fragments

    NARCIS (Netherlands)

    ten Cate, B.; Litak, T.; Marx, M.

    2010-01-01

    We provide complete axiomatizations for several fragments of Core XPath, the navigational core of XPath 1.0 introduced by Gottlob, Koch and Pichler. A complete axiomatization for a given fragment is a set of equivalences from which every other valid equivalence is derivable; equivalences can be thou

  14. Deteksi Antibodi Serum Terhadap Virus Avian influenza pada Ayam Buras

    Directory of Open Access Journals (Sweden)

    Darmawi Darmawi

    2012-04-01

    Full Text Available Detection on Serum Antibodies of Native Chickens to Avian influenza Virus ABSTRACT.  An important approach of controlling against Avian Influenza should be determined to detect the antibody titres of bird flu caused by Influenza virus H5N1 in Indonesia. The aim of the present study was to detect the antibodies to Avian Influenza in serum of native chickens. This study utilized 123 serum samples collected from the axilaris vein (left or right of native chickens. Antibody titres were examined using Hemaglutination Inhibition (HI. The result showed that indication of natural infection by Avian Influenza (H5N1 in native chickens, as shown that out of 123 serum samples, 16 (13,01% were tested positive by HI, while only 10 (8,13% were tested protective to Avian influenza infection. Based on the results we obtained, a conclusion that natural infection by Avian influenza virus stimulated variety level of formation antibody titres in native chickens.

  15. Isolation of recombinant phage antibodies targeting the hemagglutinin cleavage site of highly pathogenic avian influenza virus.

    Directory of Open Access Journals (Sweden)

    Jinhua Dong

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 viruses, which have emerged in poultry and other wildlife worldwide, contain a characteristic multi-basic cleavage site (CS in the hemagglutinin protein (HA. Because this arginine-rich CS is unique among influenza virus subtypes, antibodies against this site have the potential to specifically diagnose pathogenic H5N1. By immunizing mice with the CS peptide and screening a phage display library, we isolated four antibody Fab fragment clones that specifically bind the antigen peptide and several HPAI H5N1 HA proteins in different clades. The soluble Fab fragments expressed in Escherichia coli bound the CS peptide and the H5N1 HA protein with nanomolar affinity. In an immunofluorescence assay, these Fab fragments stained cells infected with HPAI H5N1 but not those infected with a less virulent strain. Lastly, all the Fab clones could detect the CS peptide and H5N1 HA protein by open sandwich ELISA. Thus, these recombinant Fab fragments will be useful novel reagents for the rapid and specific detection of HPAI H5N1 virus.

  16. 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.

  17. Avian influenza virus and free-ranging wild birds

    Science.gov (United States)

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

    2006-01-01

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

  18. 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.

  19. Avian Interferons and Their Antiviral Effectors

    OpenAIRE

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of I...

  20. The avian fossil record in Insular Southeast Asia and its implications for avian biogeography and palaeoecology.

    Science.gov (United States)

    Meijer, Hanneke J M

    2014-01-01

    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.

  1. Seroprevalence of avian hepatitis E virus and avian leucosis virus subgroup J in chicken flocks with hepatitis syndrome, China

    OpenAIRE

    Sun, Yani; Du, Taofeng; Liu, Baoyuan; Syed, Shahid Faraz; Chen, Yiyang; Li, Huixia; Wang, Xinjie; Zhang, Gaiping; Zhou, En-Min; Zhao, Qin

    2016-01-01

    Background From 2014 to 2015 in China, many broiler breeder and layer hen flocks exhibited a decrease in egg production and some chickens developed hepatitis syndrome including hepatomegaly, hepatic necrosis and hemorrhage. Avian hepatitis E virus (HEV) and avian leucosis virus subgroup J (ALV-J) both cause decreasing in egg production, hepatomegaly and hepatic hemorrhage in broiler breeder and layer hens. In the study, the seroprevalence of avian HEV and ALV-J in these flocks emerging the di...

  2. Driven fragmentation of granular gases.

    Science.gov (United States)

    Cruz Hidalgo, Raúl; Pagonabarraga, Ignacio

    2008-06-01

    The dynamics of homogeneously heated granular gases which fragment due to particle collisions is analyzed. We introduce a kinetic model which accounts for correlations induced at the grain collisions and analyze both the kinetics and relevant distribution functions these systems develop. The work combines analytical and numerical studies based on direct simulation Monte Carlo calculations. A broad family of fragmentation probabilities is considered, and its implications for the system kinetics are discussed. We show that generically these driven materials evolve asymptotically into a dynamical scaling regime. If the fragmentation probability tends to a constant, the grain number diverges at a finite time, leading to a shattering singularity. If the fragmentation probability vanishes, then the number of grains grows monotonously as a power law. We consider different homogeneous thermostats and show that the kinetics of these systems depends weakly on both the grain inelasticity and driving. We observe that fragmentation plays a relevant role in the shape of the velocity distribution of the particles. When the fragmentation is driven by local stochastic events, the long velocity tail is essentially exponential independently of the heating frequency and the breaking rule. However, for a Lowe-Andersen thermostat, numerical evidence strongly supports the conjecture that the scaled velocity distribution follows a generalized exponential behavior f(c) approximately exp(-cn) , with n approximately 1.2 , regarding less the fragmentation mechanisms.

  3. Avian Interferons and Their Antiviral Effectors

    Science.gov (United States)

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of IFNs have been genetically characterized in most avian species with available annotated genomes. Intriguingly, chickens are capable of mounting potent innate immune responses upon various stimuli in the absence of essential components of IFN pathways including retinoic acid-inducible gene I, IFN regulatory factor 3 (IRF3), and possibility IRF9. Understanding these unique properties of the chicken IFN system would propose valuable targets for the development of potential therapeutics for a broader range of viruses of both veterinary and zoonotic importance. This review outlines recent developments in the roles of avian IFNs and ISGs against viruses and highlights important areas of research toward our understanding of the antiviral functions of IFN effectors against viral infections in birds. PMID:28197148

  4. Avian cytokines in health and disease

    Directory of Open Access Journals (Sweden)

    P Wigley

    2003-04-01

    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.

  5. Avian Interferons and Their Antiviral Effectors.

    Science.gov (United States)

    Santhakumar, Diwakar; Rubbenstroth, Dennis; Martinez-Sobrido, Luis; Munir, Muhammad

    2017-01-01

    Interferon (IFN) responses, mediated by a myriad of IFN-stimulated genes (ISGs), are the most profound innate immune responses against viruses. Cumulatively, these IFN effectors establish a multilayered antiviral state to safeguard the host against invading viral pathogens. Considerable genetic and functional characterizations of mammalian IFNs and their effectors have been made, and our understanding on the avian IFNs has started to expand. Similar to mammalian counterparts, three types of IFNs have been genetically characterized in most avian species with available annotated genomes. Intriguingly, chickens are capable of mounting potent innate immune responses upon various stimuli in the absence of essential components of IFN pathways including retinoic acid-inducible gene I, IFN regulatory factor 3 (IRF3), and possibility IRF9. Understanding these unique properties of the chicken IFN system would propose valuable targets for the development of potential therapeutics for a broader range of viruses of both veterinary and zoonotic importance. This review outlines recent developments in the roles of avian IFNs and ISGs against viruses and highlights important areas of research toward our understanding of the antiviral functions of IFN effectors against viral infections in birds.

  6. Responses of seed-dispersing birds to amount of rainforest in the landscape around fragments.

    Science.gov (United States)

    Moran, Cath; Catterall, Carla P

    2014-04-01

    Habitat loss and fragmentation alter the composition of bird assemblages in rainforest. Because birds are major seed dispersers in rainforests, fragmentation-induced changes to frugivorous bird assemblages are also likely to alter the ecological processes of seed dispersal and forest regeneration, but the specific nature of these changes is poorly understood. We assessed the influence of fragment size and landscape forest cover on the abundance, species composition, and functional properties of the avian seed disperser community in an extensively cleared, former rainforest landscape of subtropical Australia. Bird surveys of fixed time and area in 25 rainforest fragments (1-139 ha in size across a 1800 km(2) region) provided bird assemblage data which were coupled with prior knowledge of bird species' particular roles in seed dispersal to give measurements of seven different attributes of the seed disperser assemblage. We used multimodel regression to assess how patch size and surrounding forest cover (within 200 m, 1000 m, and 5000 m radii) influenced variation in the abundance of individual bird species and of functional groups based on bird species' responses to fragmentation and their roles in seed dispersal. Surrounding forest cover, specifically rainforest cover, generally had a greater effect on frugivorous bird assemblages than fragment size. Amount of rainforest cover within 200 m of fragments was the main factor positively associated with abundances of frugivorous birds that are both fragmentation sensitive and important seed dispersers. Our results suggest a high proportion of local rainforest cover is required for the persistence of seed-dispersing birds and the maintenance of seed dispersal processes. Thus, even small rainforest fragments can function as important parts of habitat networks for seed-dispersing birds, whether or not they are physically connected by vegetation.

  7. The spectroscopy of fission fragments

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, W.R. [Department of Physics and Astronomy, University of Manchester, Manchester, M13 9PL (United Kingdom); Collaboration: La Direction des Sciences de la Matiere du CEA (FR); Le Fonds National de la Recherche Scientifique de Belgique (BE)

    1998-12-31

    High-resolution measurements on {gamma} rays from fission fragments have provided a rich source of information, unobtainable at the moment in any other way, on the spectroscopy of neutron-rich nuclei. In recent years important data have been obtained on the yrast- and near yrast-structure of neutron-rich fission fragments. We discuss the scope of measurements which can be made on prompt gamma rays from secondary fission fragments, the techniques used in the experiments and some results recently obtained. (author) 24 refs., 8 figs., 1 tab.

  8. Role of the key mutation in the selective binding of avian and human influenza hemagglutinin to sialosides revealed by quantum-mechanical calculations.

    Science.gov (United States)

    Sawada, Toshihiko; Fedorov, Dmitri G; Kitaura, Kazuo

    2010-12-01

    The selective binding between avian and human influenza A viral hemagglutinins (HA) subtype H3 and Neu5Acα2-3 and α2-6Gal (avian α2-3, human α2-6) is qualitatively rationalized by the fragment molecular orbital (FMO) method. We suggest a general model of analyzing protein-ligand interactions based on the electrostatic, polarization, dispersion, and desolvation components obtained from quantum-mechanical calculations at the MP2/6-31G(d) level with the polarizable continuum model of solvation. The favorable avian H3 (A/duck/Ukraine/1963)-avian α2-3 binding arises from the hydrophilic interaction between Gal-4 OH and side-chain NH(2)CO on Gln226, which is supported by the intermolecular hydrogen-bond network to the 1-COO group on Neu5Ac moiety. A substitution of Gln226Leu in the avian H3 HA1 domain increases the binding affinity to human α2-6 due to the Leu226···human α2-6 dispersion with a small entropic penalty during the complex formation. The remarkable human H3 (A/Aichi/2/1968)-human α2-6 binding is not governed by the Ser228-OH···OH-9 Neu5Ac hydrogen bond. These fragment-based chemical aspects can help design monovalent inhibitors of the influenza viral HA-sialoside binding and the simulation studies on the viral HAs-human α2-6 binding.

  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. 9 CFR 113.326 - Avian Pox Vaccine.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Avian Pox Vaccine. 113.326 Section 113... Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus... this section shall be used for preparing the production seed virus for vaccine production. All...

  11. 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.

  12. 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, ...

  13. Putative Novel Genotype of Avian Hepatitis E Virus, Hungary, 2010

    OpenAIRE

    Bányai, Krisztián; Tóth, Ádám György; Ivanics, Éva; Glávits, Róbert; Szentpáli-Gavallér, Katalin; Dán, Ádám

    2012-01-01

    To explore the genetic diversity of avian hepatitis E virus strains, we characterized the near-complete genome of a strain detected in 2010 in Hungary, uncovering moderate genome sequence similarity with reference strains. Public health implications related to consumption of eggs or meat contaminated by avian hepatitis E virus, or to poultry handling, require thorough investigation.

  14. Putative novel genotype of avian hepatitis E virus, Hungary, 2010.

    Science.gov (United States)

    Bányai, Krisztián; Tóth, Ádám György; Ivanics, Éva; Glávits, Róbert; Szentpáli-Gavallér, Katalin; Dán, Ádám

    2012-08-01

    To explore the genetic diversity of avian hepatitis E virus strains, we characterized the near-complete genome of a strain detected in 2010 in Hungary, uncovering moderate genome sequence similarity with reference strains. Public health implications related to consumption of eggs or meat contaminated by avian hepatitis E virus, or to poultry handling, require thorough investigation.

  15. China's Cool Handling of Avian Flu

    Institute of Scientific and Technical Information of China (English)

    LIWUZHOU

    2004-01-01

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

  16. Avian Influenza Viruses in Water Birds, Africa 1

    OpenAIRE

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

    2007-01-01

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

  17. Poultry-handling Practices during Avian Influenza Outbreak, Thailand

    OpenAIRE

    Sonja J Olsen; Laosiritaworn, Yongjua; Pattanasin, Sarika; Prapasiri, Prabda; Scott F Dowell

    2005-01-01

    With poultry outbreaks of avian influenza H5N1 continuing in Thailand, preventing human infection remains a priority. We surveyed residents of rural Thailand regarding avian influenza knowledge, attitudes, and practices. Results suggest that public education campaigns have been effective in reaching those at greatest risk, although some high-risk behavior continues.

  18. 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.

  19. Exploring the avian gut microbiota: current trends and future directions.

    Science.gov (United States)

    Waite, David W; Taylor, Michael W

    2015-01-01

    Birds represent a diverse and evolutionarily successful lineage, occupying a wide range of niches throughout the world. Like all vertebrates, avians harbor diverse communities of microorganisms within their guts, which collectively fulfill crucial roles in providing the host with nutrition and protection from pathogens. Across the field of avian microbiology knowledge is extremely uneven, with several species accounting for an overwhelming majority of all microbiological investigations. These include agriculturally important birds, such as chickens and turkeys, as well as birds of evolutionary or conservation interest. In our previous study we attempted the first meta-analysis of the avian gut microbiota, using 16S rRNA gene sequences obtained from a range of publicly available data sets. We have now extended our analysis to explore the microbiology of several key species in detail, to consider the avian microbiota within the context of what is known about other vertebrates, and to identify key areas of interest in avian microbiology for future study.

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

    Directory of Open Access Journals (Sweden)

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

    2011-10-01

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

  1. Identification of a novel B-cell epitope specific for avian leukosis virus subgroup J gp85 protein.

    Science.gov (United States)

    Li, Xiaofei; Zhu, Haibo; Wang, Qi; Sun, Jiashan; Gao, Yanni; Qi, Xiaole; Wang, Yongqiang; Gao, Honglei; Gao, Yulong; Wang, Xiaomei

    2015-04-01

    Avian leukosis virus subgroup J (ALV-J) is an avian oncogenic retrovirus that has caused severe economic losses in China. Gp85 protein is the main envelope protein and the most variable structural protein of ALV-J. It is also involved in virus neutralization. In this study, a specific monoclonal antibody, 4A3, was produced against the ALV-J gp85 protein. Immunofluorescence assays showed that 4A3 could react with different strains of ALV-J, including the British prototype isolate HPRS103, the American strains, an early Chinese broiler isolate, and layer isolates. A linear epitope on the gp85 protein was identified using a series of partially overlapping fragments spanning the gp85-encoding gene and subjecting them to western blot analysis. The results indicated that (134)AEAELRDFI(142) was the minimal linear epitope that could be recognized by mAb 4A3. Enzyme-linked immunosorbent assay (ELISA) revealed that chicken anti-ALV-J sera and mouse anti-ALV-J gp85 sera could also recognize the minimal linear epitope. Alignment analysis of amino acid sequences indicated that the epitope was highly conserved among 34 ALV-J strains. Furthermore, the epitope was not conserved among subgroup A and B of avian leukosis virus (ALV). Taken together, the mAb and the identified epitope may provide valuable tools for the development of new diagnostic methods for ALV-J.

  2. Avian-specific real-time PCR assay for authenticity control in farm animal feeds and pet foods.

    Science.gov (United States)

    Pegels, Nicolette; González, Isabel; García, Teresa; Martín, Rosario

    2014-01-01

    A highly sensitive TaqMan real-time PCR assay targeting the mitochondrial 12S rRNA gene was developed for detection of an avian-specific DNA fragment (68bp) in farm animal and pet feeds. The specificity of the assay was verified against a wide representation of animal and plant species. Applicability assessment of the avian real-time PCR was conducted through representative analysis of two types of compound feeds: industrial farm animal feeds (n=60) subjected to extreme temperatures, and commercial dog and cat feeds (n=210). Results obtained demonstrated the suitability of the real-time PCR assay to detect the presence of low percentages of highly processed avian material in the feed samples analysed. Although quantification results were well reproducible under the experimental conditions tested, an accurate estimation of the target content in feeds is impossible in practice. Nevertheless, the method may be useful as an alternative tool for traceability purposes within the framework of feed control.

  3. Richness, composition and trophic groups of an avian community in the Pernambuco Endemism Centre, Alagoas, Brazil.

    Science.gov (United States)

    Toledo-Lima, Guilherme S; Macario, Phoeve; Lyra-Neves, Rachel M de; Teixeira, Bruno P; Lima, Luiz A F de; Sugliano, Gabriel O S; Telino-Júnior, Wallace R

    2014-09-01

    In northeastern Brazil, the reduction of the natural forest cover to a series of small, isolated fragments has had negative consequences for the local avian fauna, in particular, a loss of the more specialized species, while the populations of some generalists have tended to increase. The present study focuses on the composition and trophic groups of a bird community on a farm in the northeastern Brazilian state of Alagoas. Monthly surveys were conducted between November 2008 and October 2009, based on mist-netting and systematic observations. Overall, 112 species were recorded, of which 76 were associated with the two forest fragments surveyed, while all the others were observed exclusively in the surrounding matrix of pasture and orchards. The bird community presented a predominance of insectivorous species, followed by omnivores. However, specialized trunk-creeping and understory insectivores accounted for only around 15% of the species in this feeding category. The reduced diversity of other guilds and species with more specialized diets, and the complete absence of sensitive species such as large parrots and raptors, reflects the severe fragmentation and degradation of the local forests, which has greatly reduced the availability of dietary resources and breeding sites.

  4. Richness, composition and trophic groups of an avian community in the Pernambuco Endemism Centre, Alagoas, Brazil

    Directory of Open Access Journals (Sweden)

    GUILHERME S. TOLEDO-LIMA

    2014-09-01

    Full Text Available In northeastern Brazil, the reduction of the natural forest cover to a series of small, isolated fragments has had negative consequences for the local avian fauna, in particular, a loss of the more specialized species, while the populations of some generalists have tended to increase. The present study focuses on the composition and trophic groups of a bird community on a farm in the northeastern Brazilian state of Alagoas. Monthly surveys were conducted between November 2008 and October 2009, based on mist-netting and systematic observations. Overall, 112 species were recorded, of which 76 were associated with the two forest fragments surveyed, while all the others were observed exclusively in the surrounding matrix of pasture and orchards. The bird community presented a predominance of insectivorous species, followed by omnivores. However, specialized trunk-creeping and understory insectivores accounted for only around 15% of the species in this feeding category. The reduced diversity of other guilds and species with more specialized diets, and the complete absence of sensitive species such as large parrots and raptors, reflects the severe fragmentation and degradation of the local forests, which has greatly reduced the availability of dietary resources and breeding sites.

  5. An optimized polymerase chain reaction assay to identify avian virus vaccine contamination with Chicken anemia virus.

    Science.gov (United States)

    Amer, Haitham M; Elzahed, Hanan M; Elabiare, Elham A; Badawy, Ahmed A; Yousef, Ausama A

    2011-01-01

    The use of embryonating chicken eggs in preparation of avian virus vaccines is the principle cause for contamination with Chicken anemia virus (CAV). Identification of CAV in contaminated vaccines relies on the expensive, tedious, and time-consuming practice of virus isolation in lymphoblastoid cell lines. The experience of the last 2 decades indicates that polymerase chain reaction is extending to replace most of the classic methods for detection of infectious agents. In the present report, a simple, rapid, and accurate polymerase chain reaction method for detection of CAV in poultry vaccines is described. Oligonucleotide primers homologous to highly conserved sequences of the VP1 gene were used to amplify a fragment of 676 bp. The developed assay was specific for detecting CAV from different sources, with no cross reactivity with many avian viruses. No inter- and intra-assay variations were observed. The analytical sensitivity of the test was high enough to detect 5 TCID(50) (50% tissue culture infective dose) of the virus per reaction; however, different factors related to the vaccine matrix showed considerable effects on the detection limit. In conclusion, this method may represent a suitable alternative to virus isolation for identification of CAV contamination of poultry virus vaccines.

  6. Endogenous avian leukosis viral loci in the Red Jungle Fowl genome assembly.

    Science.gov (United States)

    Benkel, Bernhard; Rutherford, Katherine

    2014-12-01

    The current build (galGal4) of the genome of the ancestor of the modern chicken, the Red Jungle Fowl, contains a single endogenous avian leukosis viral element (ALVE) on chromosome 1 (designated RSV-LTR; family ERVK). The assembly shows the ALVE provirus juxtaposed with a member of a second family of avian endogenous retroviruses (designated GGERV20; family ERVL); however, the status of the 3' end of the ALVE element as well as its flanking region remain unclear due to a gap in the reference genome sequence. In this study, we filled the gap in the assembly using a combination of long-range PCR (LR-PCR) and a short contig present in the unassembled portion of the reference genome database. Our results demonstrate that the ALVE element (ALVE-JFevB) is inserted into the putative envelope region of a GGERV20 element, roughly 1 kbp from its 3' end, and that ALVE-JFevB is complete, and depending on its expression status, potentially capable of directing the production of virus. Moreover, the unassembled portion of the genome database contains junction fragments for a second, previously characterized endogenous proviral element, ALVE-6.

  7. A pmp genes-based PCR as a valuable tool for the diagnosis of avian chlamydiosis.

    Science.gov (United States)

    Laroucau, Karine; Trichereau, Alain; Vorimore, Fabien; Mahé, Anne-Marie

    2007-03-31

    In a previous study we described the use of a new set of PCR primers (CpsiA/CpsiB) specific of the conserved pmp-family genes of Chlamydophila abortus as an efficient tool for the detection of these bacteria in ruminants including also preliminary results on avian strains. In this work, the use of this set of primers was extended to representative strains of the six major avian serovars (serovars A-F) and to field isolates of C. psittaci. For all the studied representative strains, using purified genomic DNA as a template, CpsiA/CpsiB primers allowed, as observed for C. abortus, a minimal 10-fold PCR signal increase compared to the one observed with ompA specific primers. In comparison to primers targeting the 16S-23S rRNA intergenic spacer, similar or increased sensitivity was observed depending on the strain. All the field isolates were amplified with CpsiA/CpsiB primers. On clinical samples, our primers are the best among those tested for detection of C. psittaci by simple conventional PCR. RFLP experiments performed using PCR fragments amplified with the CpsiA/CpsiB primers gave promising results demonstrating that these primers may provide an interesting tool for molecular typing when the bacterium cannot be grown from pathological samples.

  8. 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.

  9. 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

  10. Avian artificial insemination and semen preservation

    Science.gov (United States)

    Gee, G.F.; Risser, Arthur C.; Todd, Frank S.

    1983-01-01

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

  11. Meiotic silencing and fragmentation of the male germline restricted chromosome in zebra finch.

    Science.gov (United States)

    Schoenmakers, Sam; Wassenaar, Evelyne; Laven, Joop S E; Grootegoed, J Anton; Baarends, Willy M

    2010-06-01

    During male meiotic prophase in mammals, X and Y are in a largely unsynapsed configuration, which is thought to trigger meiotic sex chromosome inactivation (MSCI). In avian species, females are ZW, and males ZZ. Although Z and W in chicken oocytes show complete, largely heterologous synapsis, they too undergo MSCI, albeit only transiently. The W chromosome is already inactive in early meiotic prophase, and inactive chromatin marks may spread on to the Z upon synapsis. Mammalian MSCI is considered as a specialised form of the general meiotic silencing mechanism, named meiotic silencing of unsynapsed chromatin (MSUC). Herein, we studied the avian form of MSUC, by analysing the behaviour of the peculiar germline restricted chromosome (GRC) that is present as a single copy in zebra finch spermatocytes. In the female germline, this chromosome is present in two copies, which normally synapse and recombine. In contrast, during male meiosis, the single GRC is always eliminated. We found that the GRC in the male germline is silenced from early leptotene onwards, similar to the W chromosome in avian oocytes. The GRC remains largely unsynapsed throughout meiotic prophase I, although patches of SYCP1 staining indicate that part of the GRC may self-synapse. In addition, the GRC is largely devoid of meiotic double strand breaks. We observed a lack of the inner centromere protein INCENP on the GRC and elimination of the GRC following metaphase I. Subsequently, the GRC forms a micronucleus in which the DNA is fragmented. We conclude that in contrast to MSUC in mammals, meiotic silencing of this single chromosome in the avian germline occurs prior to, and independent of DNA double strand breaks and chromosome pairing, hence we have named this phenomenon meiotic silencing prior to synapsis (MSPS).

  12. Nuclear energy release from fragmentation

    CERN Document Server

    Li, Cheng; Tsang, M B; Zhang, Feng-Shou

    2015-01-01

    Nuclear energy released by splitting Uranium and Thorium isotopes into two, three, four, up to eight fragments with nearly equal size are studied. We found that the energy released come from equally splitting the $^{235,238}$U and $^{230,232}$Th nuclei into to three fragments is largest. The statistical multifragmentation model is employed to calculate the probability of different breakup channels for the excited nuclei. Weighing the the probability distributions of fragments multiplicity at different excitation energies for the $^{238}$U nucleus, we found that an excitation energy between 1.2 and 2 MeV/u is optimal for the $^{235}$U, $^{238}$U, $^{230}$Th and $^{232}$Th nuclei to release nuclear energy of about 0.7-0.75 MeV/u.

  13. RIA Fragmentation Line Beam Dumps

    Energy Technology Data Exchange (ETDEWEB)

    Stein, W

    2003-08-08

    The Rare Isotope Accelerator project involves generating heavy-element ion beams for use in a fragmentation target line to produce beams for physics research. The main beam, after passing through the fragmentation target, may be dumped into a beam dump located in the vacuum cavity of the first dipole magnet. For a dump beam power of 100 kW, cooling is required to avoid excessive high temperatures. The proposed dump design involves rotating cylinders to spread out the energy deposition and turbulent subcooled water flow through internal water cooling passages to obtain high, nonboiling, cooling rates.

  14. Transversity and dihadron fragmentation functions

    CERN Document Server

    Bacchetta, A; Bacchetta, Alessandro; Radici, Marco

    2005-01-01

    The observation of the quark transversity distribution requires another soft object sensitive to the quark's transverse spin. Dihadron fragmentation functions represent a convenient tool to analyze partonic spin, which can influence the angular distribution of the two hadrons. In particular, the so-called interference fragmentation functions can be used to probe transversity both in semi-inclusive deep inelastic scattering as well as proton-proton collisions. We discuss two single-spin asymmetries sensitive to transversity in the these two processes, at leading twist and leading order in alpha_S.

  15. Phenomenology of Dihadron Fragmentation Function

    CERN Document Server

    Courtoy, A

    2016-01-01

    We report on the phenomenological results obtained through Dihadron Fragmentation Functions related processes. In 2015, an update on the fitting techniques for the Dihadron Fragmentation Functions has led to an improved extraction of the transversity PDF and, as a consequence, the nucleon tensor charge. We discuss the impact of the determination of the latter on search for physics Beyond the Standard Model, focusing on the error treatment. We also comment on the future of the extraction of the subleading-twist PDF $e(x)$ from JLab soon-to-be-released Beam Spin Asymmetry data.

  16. 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.

  17. Avian Bornaviruses in North American Gulls.

    Science.gov (United States)

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

    2015-07-01

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

  18. 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.

  19. Collapsing avian community on a Hawaiian island

    Science.gov (United States)

    Paxton, Eben; Camp, Richard J.; Gorresen, P. Marcos; Crampton, Lisa H.; Leonard, David L.; VanderWerf, Eric

    2016-01-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing.

  20. A thermodynamic theory of dynamic fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Yew, Ching H. [Texas Univ., Austin, TX (United States); Taylor, P.A. [Sandia National Labs., Albuquerque, NM (United States)

    1993-08-01

    We present a theory of dynamic fragmentation of brittle materials based on thermodynamic arguments. We recover the expressions for average fragment size and number as originally derived by Grady. We extend the previous work by obtaining descriptions of fragment size distribution and compressibility change due to the fragmentation process. The size distribution is assumed to be proportional to the spectral power of the strain history and a sample distribution is presented for a fragmentation process corresponding to a constant rate strain history. The description of compressibility change should be useful in computational studies of fragmentation. These results should provide insight into the process of fragmentation of brittle materials from hypervelocity impact.

  1. The Fragmentation of Literary Theory

    Science.gov (United States)

    Howard, Jennifer

    2005-01-01

    Syllabi from some 20 colleges and universities were reviewed with prominent English and literature departments and a discussion was held with a number of professors who teach literary theory. It is suggested that devolution and fragmentation of theory might be a survival strategy, an adaptation to the new realties of academic institutions.

  2. Fragmented nature : consequences for biodiversity

    NARCIS (Netherlands)

    Olff, Han; Ritchie, Mark E.

    2002-01-01

    We discuss how fragmentation of resources and habitat operate differently on species diversity across spatial scales, ranging from positive effects on local species coexistence to negative effect on intermediate spatial scales, to again positive effects on large spatial and temporal scales. Species

  3. Fragmented nature: consequences for biodiversity

    NARCIS (Netherlands)

    Olff, H.; Ritchie, M.E.

    2002-01-01

    We discuss how fragmentation of resources and habitat operate differently on species diversity across spatial scales, ranging from positive effects on local species coexistence to negative effect on intermediate spatial scales, to again positive effects on large spatial and temporal scales. Species

  4. Nuclear energy release from fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Cheng [The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Souza, S.R. [Instituto de Física, Universidade Federal do Rio de Janeiro Cidade Universitária, Caixa Postal 68528, 21945-970 Rio de Janeiro (Brazil); Tsang, M.B. [The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); National Superconducting Cyclotron Laboratory and Physics and Astronomy Department, Michigan State University, East Lansing, MI 48824 (United States); Zhang, Feng-Shou, E-mail: fszhang@bnu.edu.cn [The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000 (China)

    2016-08-15

    It is well known that binary fission occurs with positive energy gain. In this article we examine the energetics of splitting uranium and thorium isotopes into various numbers of fragments (from two to eight) with nearly equal size. We find that the energy released by splitting {sup 230,232}Th and {sup 235,238}U into three equal size fragments is largest. The statistical multifragmentation model (SMM) is applied to calculate the probability of different breakup channels for excited nuclei. By weighing the probability distributions of fragment multiplicity at different excitation energies, we find the peaks of energy release for {sup 230,232}Th and {sup 235,238}U are around 0.7–0.75 MeV/u at excitation energy between 1.2 and 2 MeV/u in the primary breakup process. Taking into account the secondary de-excitation processes of primary fragments with the GEMINI code, these energy peaks fall to about 0.45 MeV/u.

  5. Nuclear energy release from fragmentation

    Science.gov (United States)

    Li, Cheng; Souza, S. R.; Tsang, M. B.; Zhang, Feng-Shou

    2016-08-01

    It is well known that binary fission occurs with positive energy gain. In this article we examine the energetics of splitting uranium and thorium isotopes into various numbers of fragments (from two to eight) with nearly equal size. We find that the energy released by splitting 230,232Th and 235,238U into three equal size fragments is largest. The statistical multifragmentation model (SMM) is applied to calculate the probability of different breakup channels for excited nuclei. By weighing the probability distributions of fragment multiplicity at different excitation energies, we find the peaks of energy release for 230,232Th and 235,238U are around 0.7-0.75 MeV/u at excitation energy between 1.2 and 2 MeV/u in the primary breakup process. Taking into account the secondary de-excitation processes of primary fragments with the GEMINI code, these energy peaks fall to about 0.45 MeV/u.

  6. The VERDI fission fragment spectrometer

    Directory of Open Access Journals (Sweden)

    Frégeau M.O.

    2013-12-01

    Full Text Available The VERDI time-of-flight spectrometer is dedicated to measurements of fission product yields and of prompt neutron emission data. Pre-neutron fission-fragment masses will be determined by the double time-of-flight (TOF technique. For this purpose an excellent time resolution is required. The time of flight of the fragments will be measured by electrostatic mirrors located near the target and the time signal coming from silicon detectors located at 50 cm on both sides of the target. This configuration, where the stop detector will provide us simultaneously with the kinetic energy of the fragment and timing information, significantly limits energy straggling in comparison to legacy experimental setup where a thin foil was usually used as a stop detector. In order to improve timing resolution, neutron transmutation doped silicon will be used. The high resistivity homogeneity of this material should significantly improve resolution in comparison to standard silicon detectors. Post-neutron fission fragment masses are obtained form the time-of-flight and the energy signal in the silicon detector. As an intermediary step a diamond detector will also be used as start detector located very close to the target. Previous tests have shown that poly-crystalline chemical vapour deposition (pCVD diamonds provides a coincidence time resolution of 150 ps not allowing complete separation between very low-energy fission fragments, alpha particles and noise. New results from using artificial single-crystal diamonds (sCVD show similar time resolution as from pCVD diamonds but also sufficiently good energy resolution.

  7. 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.

  8. The Helper Activities of Different Avian Viruses for Propagation of Recombinant Avian Adeno-Associated Virus

    Institute of Scientific and Technical Information of China (English)

    WANG An-ping; SUN Huai-chang; WANG Jian-ye; WANG Yong-juan; YUAN Wei-feng

    2007-01-01

    To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus (rAAAV), AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein (GFP) gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast (CEF) or chicken embryonic liver (CEL) cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek's disease virus (MDV), avian adenovirus, chicken embryo lethal orphan (CELO) virus or infectious bursal disease virus (IBDV). Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein (gfp) expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.

  9. Secondary structural analysis of the mRNA regions encoding the hemagglutinin cleavage site basic amino acids of the avian influenza virus H5N1 subtype samples

    Institute of Scientific and Technical Information of China (English)

    ZHANG SuXia; WANG Xin; CHEN XueFeng; CAO Huai; ZHANG Wen; LIU CiQuan

    2008-01-01

    Here we report the codon bias and the mRNA secondary structural features of the hemagglutinin (HA) cleavage site basic amino acid regions of avian influenza virus H5N1 subtypes. We have developed a dynamic extended folding strategy to predict RNA secondary structure with RNAstructure 4.1 program in an iterative extension process. Statistical analysis of the sequences showed that the HA cleavage site basic amino acids favor the adenine-rich codons, and the corresponding mRNA fragments are mainly in the folding states of single-stranded loops. Our sequential and structural analyses showed that to prevent and control these highly pathogenic viruses, that is, to inhibit the gene expression of avian influenza virus H5N1 subtypes, we should consider the single-stranded loop regions of the HA cleavage site-coding sequences as the targets of RNA interference.

  10. Efficient and accurate fragmentation methods.

    Science.gov (United States)

    Pruitt, Spencer R; Bertoni, Colleen; Brorsen, Kurt R; Gordon, Mark S

    2014-09-16

    Conspectus Three novel fragmentation methods that are available in the electronic structure program GAMESS (general atomic and molecular electronic structure system) are discussed in this Account. The fragment molecular orbital (FMO) method can be combined with any electronic structure method to perform accurate calculations on large molecular species with no reliance on capping atoms or empirical parameters. The FMO method is highly scalable and can take advantage of massively parallel computer systems. For example, the method has been shown to scale nearly linearly on up to 131 000 processor cores for calculations on large water clusters. There have been many applications of the FMO method to large molecular clusters, to biomolecules (e.g., proteins), and to materials that are used as heterogeneous catalysts. The effective fragment potential (EFP) method is a model potential approach that is fully derived from first principles and has no empirically fitted parameters. Consequently, an EFP can be generated for any molecule by a simple preparatory GAMESS calculation. The EFP method provides accurate descriptions of all types of intermolecular interactions, including Coulombic interactions, polarization/induction, exchange repulsion, dispersion, and charge transfer. The EFP method has been applied successfully to the study of liquid water, π-stacking in substituted benzenes and in DNA base pairs, solvent effects on positive and negative ions, electronic spectra and dynamics, non-adiabatic phenomena in electronic excited states, and nonlinear excited state properties. The effective fragment molecular orbital (EFMO) method is a merger of the FMO and EFP methods, in which interfragment interactions are described by the EFP potential, rather than the less accurate electrostatic potential. The use of EFP in this manner facilitates the use of a smaller value for the distance cut-off (Rcut). Rcut determines the distance at which EFP interactions replace fully quantum

  11. The avian tectorial membrane: Why is it tapered?

    CERN Document Server

    Iwasa, Kuni H

    2015-01-01

    While the mammalian- and the avian inner ears have well defined tonotopic organizations as well as hair cells specialized for motile and sensing roles, the structural organization of the avian ear is different from its mammalian cochlear counterpart. Presumably this difference stems from the difference in the way motile hair cells function. Short hair cells, whose role is considered analogous to mammalian outer hair cells, presumably depends on their hair bundles, and not motility of their cell body, in providing the motile elements of the cochlear amplifier. This report focuses on the role of the avian tectorial membrane, specifically by addressing the question, "Why is the avian tectorial membrane tapered from the neural to the abneural direction?"

  12. Historical review of avian botulism at Stillwater Wildlife Management Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to review historical information on avian botulism at Stillwater Wildlife Management Area. This report includes incidental reports of...

  13. Region 6 Avian Health Program FY2011 Annual Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report describes activities and fund allocations of the Region 6 Avian Health Program in FY2011. Activities include morbidity and mortality monitoring, disease...

  14. Avian influenza surveillance sample collection and shipment protocol

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Instructions for mortality collection and shipment of avian influenza (AI) live bird surveillance sample collections. AI sample collections will include...

  15. Markov Chain Estimation of Avian Seasonal Fecundity, Presentation

    Science.gov (United States)

    Avian seasonal fecundity is of interest from evolutionary, ecological, and conservation perspectives. However, direct estimation of seasonal fecundity is difficult, especially with multibrooded birds, and models representing the renesting and quitting processes are usually requi...

  16. Avian Point Transect Survey; Seward Peninsula, Alaska, 2012

    Data.gov (United States)

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

  17. The 3rd International Symposium on Avian Brood Parasitism

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    正Invited participants on the 3rd International Symposium on Avian Brood Parasitism, sponsored by Hainan Normal University (HNU), China, Norwegian University of Science and Technology (NTNU), Norway, the Research Council of Norway, and China Ornithological Society (COS).

  18. Migratory Bird Avian Influenza Sampling; Yukon Kuskokwim Delta, Alaska, 2015

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data set containing avian influenza sampling information for spring and summer waterbirds on the Yukon Kuskokwim Delta, 2015. Data contains sample ID, species common...

  19. Avian populations and habitat use in interior Alaska taiga

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Avian community structure, habitat occupancy levels, and species habitat use patterns were examined in the woody habitats of interior Alaska taiga. Some birds...

  20. Avian Flu (H7N9) in China

    Science.gov (United States)

    ... Mobile Apps RSS Feeds Avian Flu (H7N9) in China Recommend on Facebook Tweet Share Compartir Warning - Level ... of H7N9 have been reported outside of mainland China but most of these infections have occurred among ...

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

    Science.gov (United States)

    ... their saliva, mucous and feces. Human infections with bird flu viruses can happen when enough virus gets into ... Virus (CVV) for a Highly Pathogenic Avian Influenza (Bird Flu) Virus ” for more information on this process. ...

  2. 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.

  3. Brachyspira pilosicoli-induced avian intestinal spirochaetosis

    Directory of Open Access Journals (Sweden)

    Caroline I. Le Roy

    2015-12-01

    Full Text Available Avian intestinal spirochaetosis (AIS is a common disease occurring in poultry that can be caused by Brachyspira pilosicoli, a Gram-negative bacterium of the order Spirochaetes. During AIS, this opportunistic pathogen colonises the lower gastrointestinal (GI tract of poultry (principally, the ileum, caeca, and colon, which can cause symptoms such as diarrhoea, reduced growth rate, and reduced egg production and quality. Due to the large increase of bacterial resistance to antibiotic treatment, the European Union banned in 2006 the prophylactic use of antibiotics as growth promoters in livestock. Consequently, the number of outbreaks of AIS has dramatically increased in the UK resulting in significant economic losses. This review summarises the current knowledge about AIS infection caused by B. pilosicoli and discusses various treatments and prevention strategies to control AIS.

  4. 禽流感%Avian influenza

    Institute of Scientific and Technical Information of China (English)

    范学工; 龙云铸

    2005-01-01

    禽流感(avian influenza)是禽类流行性感冒的简称,是由甲型流感病毒株的某些亚型引起的急性呼吸道传染病。通常情况下,禽流感病毒并不感染人类,但自1997年禽甲型流感病毒H5N1感染人类之后,相继有H9N2、H7N7.亚型感染人类和H5N1再次感染人类的报道,引起了世人的广泛关注。

  5. 禽流感病%Avian Influenza

    Institute of Scientific and Technical Information of China (English)

    周先志

    1999-01-01

    @@ 禽流感病(avian influenza)是由甲型流感病毒引起的一种禽类疾病综合征.1997年5月,我国香港特别行政区1例3岁儿童死于不明原因的多器官功能衰竭,同年8月经美国疾病预防和控制中心以及WHO荷兰鹿特丹国家流感中心鉴定为禽甲型流感病毒H5N1[A(H5N1)]引起的人类流感[1~3].这是世界上首次证实A(H5N1)感染人类,因而引起医学界的广泛关注.

  6. Ribonucleoprotein of avian infectious bronchitis virus.

    Science.gov (United States)

    Davies, H A; Dourmashkin, R R; Macnaughton, M R

    1981-03-01

    The ribonucleoprotein (RNP) of avian infectious bronchitis virus (IBV) was examined by electron microscopy after shadowing with carbon/platinum. Linear RNP strands up to 6.7 microns in length, from three IVB strains, were sensitive to both pancreatic RNase and to proteases. These strands were obtained from spontaneously disrupted complete particles but not from disrupted incomplete particles that lacked RNP. They were also released from Nonidet P40-disrupted particles and could be isolated on sucrose density gradients at a density of 1.27 g/ml. In some cases, helical RNP complexes associated with virus particles were observed that were similar to RNPs of human coronavirus strain 229E and mouse hepatitis virus strain 3.

  7. Seroprevalence of avian pneumovirus in Minnesota turkeys.

    Science.gov (United States)

    Goyal, Sagar M; Lauer, Dale; Friendshuh, Keith; Halvorson, David A

    2003-01-01

    Avian pneumovirus (APV) causes respiratory tract infection in turkeys and was first seen in the United States in Colorado in late 1996. In early 1997, the disease was recognized in Minnesota and caused estimated losses of up to 15 million dollars per year. This virus has not been reported in the other turkey producing states. We here report the seroprevalence of APV in Minnesota from August 1998 to July 2002. The average rate of seroprevalence has been 36.3% (range = 14.2%-64.8%). A seasonal bias was observed, with peak incidences in the fall and spring. A higher rate of seropositivity was observed in counties with the highest concentration of turkeys.

  8. Identifying avian sources of faecal contamination using sterol analysis.

    Science.gov (United States)

    Devane, Megan L; Wood, David; Chappell, Andrew; Robson, Beth; Webster-Brown, Jenny; Gilpin, Brent J

    2015-10-01

    Discrimination of the source of faecal pollution in water bodies is an important step in the assessment and mitigation of public health risk. One tool for faecal source tracking is the analysis of faecal sterols which are present in faeces of animals in a range of distinctive ratios. Published ratios are able to discriminate between human and herbivore mammal faecal inputs but are of less value for identifying pollution from wildfowl, which can be a common cause of elevated bacterial indicators in rivers and streams. In this study, the sterol profiles of 50 avian-derived faecal specimens (seagulls, ducks and chickens) were examined alongside those of 57 ruminant faeces and previously published sterol profiles of human wastewater, chicken effluent and animal meatwork effluent. Two novel sterol ratios were identified as specific to avian faecal scats, which, when incorporated into a decision tree with human and herbivore mammal indicative ratios, were able to identify sterols from avian-polluted waterways. For samples where the sterol profile was not consistent with herbivore mammal or human pollution, avian pollution is indicated when the ratio of 24-ethylcholestanol/(24-ethylcholestanol + 24-ethylcoprostanol + 24-ethylepicoprostanol) is ≥0.4 (avian ratio 1) and the ratio of cholestanol/(cholestanol + coprostanol + epicoprostanol) is ≥0.5 (avian ratio 2). When avian pollution is indicated, further confirmation by targeted PCR specific markers can be employed if greater confidence in the pollution source is required. A 66% concordance between sterol ratios and current avian PCR markers was achieved when 56 water samples from polluted waterways were analysed.

  9. Fragmentation in filamentary molecular clouds

    CERN Document Server

    Contreras, Yanett; Rathborne, Jill M; Sanhueza, Patricio

    2015-01-01

    Recent surveys of dust continuum emission at sub-mm wavelengths have shown that filamentary molecular clouds are ubiquitous along the Galactic plane. These structures are inhomogeneous, with over-densities that are sometimes associated with infrared emission and active of star formation. To investigate the connection between filaments and star formation, requires an understanding of the processes that lead to the fragmentation of filaments and a determination of the physical properties of the over-densities (clumps). In this paper, we present a multi-wavelength study of five filamentary molecular clouds, containing several clumps in different evolutionary stages of star formation. We analyse the fragmentation of the filaments and derive the physical properties of their clumps. We find that the clumps in all filaments have a characteristic spacing consistent with the prediction of the `sausage' instability theory, regardless of the complex morphology of the filaments or their evolutionary stage. We also find t...

  10. Fragment correlations from NAUTILUS multidetector

    Energy Technology Data Exchange (ETDEWEB)

    Bizard, G. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire

    1995-12-31

    It is shown on a few examples how heavy fragment correlations, induced either by conservation laws or by Coulomb interaction can bring physical information on nuclear reactions. All the experimental data discussed have been obtained at GANIL using the NAUTILUS gaseous multi detectors DELF and XYZT, which - due to their good spatial and time resolution and their large solid angle coverage - have proved to be efficient tools for multifragment correlation studies. Different reactions of Ar, Kr, Xe, and Pb beams on Au targets are discussed. It is shown that velocity and angular correlations between fragments provide a powerful clock to scrutinize the details of the hot nuclei decay history. (K.A.). 18 refs., 6 figs.

  11. Fragment separator momentum compression schemes

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, Laura, E-mail: bandura@anl.gov [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); National Superconducting Cyclotron Lab, Michigan State University, 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Erdelyi, Bela [Argonne National Laboratory, Argonne, IL 60439 (United States); Northern Illinois University, DeKalb, IL 60115 (United States); Hausmann, Marc [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Kubo, Toshiyuki [RIKEN Nishina Center, RIKEN, Wako (Japan); Nolen, Jerry [Argonne National Laboratory, Argonne, IL 60439 (United States); Portillo, Mauricio [Facility for Rare Isotope Beams (FRIB), 1 Cyclotron, East Lansing, MI 48824-1321 (United States); Sherrill, Bradley M. [National Superconducting Cyclotron Lab, Michigan State University, 1 Cyclotron, East Lansing, MI 48824-1321 (United States)

    2011-07-21

    We present a scheme to use a fragment separator and profiled energy degraders to transfer longitudinal phase space into transverse phase space while maintaining achromatic beam transport. The first order beam optics theory of the method is presented and the consequent enlargement of the transverse phase space is discussed. An interesting consequence of the technique is that the first order mass resolving power of the system is determined by the first dispersive section up to the energy degrader, independent of whether or not momentum compression is used. The fragment separator at the Facility for Rare Isotope Beams is a specific application of this technique and is described along with simulations by the code COSY INFINITY.

  12. Fragment separator momentum compression schemes.

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, L.; Erdelyi, B.; Hausmann, M.; Kubo, T.; Nolen, J.; Portillo, M.; Sherrill, B.M. (Physics); (MSU); (Northern Illinois Univ.); (RIKEN)

    2011-07-21

    We present a scheme to use a fragment separator and profiled energy degraders to transfer longitudinal phase space into transverse phase space while maintaining achromatic beam transport. The first order beam optics theory of the method is presented and the consequent enlargement of the transverse phase space is discussed. An interesting consequence of the technique is that the first order mass resolving power of the system is determined by the first dispersive section up to the energy degrader, independent of whether or not momentum compression is used. The fragment separator at the Facility for Rare Isotope Beams is a specific application of this technique and is described along with simulations by the code COSY INFINITY.

  13. Asymmetry effects in fragment production

    Science.gov (United States)

    Kaur, Manpreet; Kaur, Varinderjit

    2016-05-01

    The production of different fragments has been studied by taking into account the mass asymmetry of the reaction and employing the momentum dependent interactions. Two different set of asymmetric reactions have been analyzed while keeping Atotal fixed using soft momentum dependent equation of state. Our results indicate that the impact of momentum dependent interactions is different in lighter projectile systems as compared to heavier ones. The comparative analysis of IQMD simulations with the experimental data in case of heavier projectile and lighter target system for the reaction of 197Au+27Al (η = 0.7) at E = 600 MeV/nucleon shows that with the inclusion of MDI we are able, upto some extent, to reproduce the experimental universality of rise and fall of intermediate mass fragments (IMFs).

  14. Avian rotavirus enteritis - an updated review.

    Science.gov (United States)

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

    2015-01-01

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

  15. History of highly pathogenic avian influenza.

    Science.gov (United States)

    Alexander, D J; Brown, I H

    2009-04-01

    The most widely quoted date for the beginning of the recorded history of avian influenza (AI) is 1878, when researchers first differentiated a disease of poultry (initially known as fowl plague but later renamed highly pathogenic avian influenza) from other diseases with high mortality rates. Current evidence indicates that highly pathogenic AI (HPAI) viruses arise through mutation after low pathogenicity AI viruses of H5 or H7 subtype are introduced into poultry. Between 1877 and 1958, a number of epizootics of HPAI occurred in most parts of the world. From 1959 to 1995, the emergence of HPAI viruses was recorded on 15 occasions, but losses were minimal. In contrast, between 1996 and 2008, HPAI viruses emerged at least 11 times and four of these outbreaks involved many millions of birds. Events during this recent period are overshadowed by the current epizootic of HPAI due to an H5N1 virus that has spread throughout Asia and into Europe and Africa, affecting over 60 countries and causing the loss of hundreds of millions of birds. All sectors of the poultry population have been affected, but free-range commercial ducks, village poultry, live bird markets and fighting cocks seem especially significant in the spread of the virus. The role of wild birds has been extensively debated but it is likely that both wild birds and domestic poultry are responsible for its spread. Even without these H5N1 outbreaks, the period 1995 to 2008 will be considered significant in the history of HPAI because of the vast numbers of birds that died or were culled in three of the other ten epizootics during this time.

  16. The fragmentation of Kosmos 2163

    Science.gov (United States)

    1992-01-01

    On 6 Dec. 1991 Kosmos 2163, a maneuverable Soviet spacecraft which had been in orbit for 58 days, experienced a major breakup at an altitude of approximately 210 km. Although numerous pieces of debris were created, the fragments decayed rapidly leaving no long-term impact on the near-Earth environment. The assessed cause of the event is the deliberate detonation of an explosive device. Details of this event are presented.

  17. Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

    Directory of Open Access Journals (Sweden)

    Sanhong Liu

    2015-01-01

    Full Text Available Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza.

  18. Avian Antimicrobial Host Defense Peptides: From Biology to Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Guolong Zhang

    2014-02-01

    Full Text Available Host defense peptides (HDPs are an important first line of defense with antimicrobial and immunomoduatory properties. Because they act on the microbial membranes or host immune cells, HDPs pose a low risk of triggering microbial resistance and therefore, are being actively investigated as a novel class of antimicrobials and vaccine adjuvants. Cathelicidins and β-defensins are two major families of HDPs in avian species. More than a dozen HDPs exist in birds, with the genes in each HDP family clustered in a single chromosomal segment, apparently as a result of gene duplication and diversification. In contrast to their mammalian counterparts that adopt various spatial conformations, mature avian cathelicidins are mostly α-helical. Avian β-defensins, on the other hand, adopt triple-stranded β-sheet structures similar to their mammalian relatives. Besides classical β-defensins, a group of avian-specific β-defensin-related peptides, namely ovodefensins, exist with a different six-cysteine motif. Like their mammalian counterparts, avian cathelicidins and defensins are derived from either myeloid or epithelial origin expressed in a majority of tissues with broad-spectrum antibacterial and immune regulatory activities. Structure-function relationship studies with several avian HDPs have led to identification of the peptide analogs with potential for use as antimicrobials and vaccine adjuvants. Dietary modulation of endogenous HDP synthesis has also emerged as a promising alternative approach to disease control and prevention in chickens.

  19. Residual Fragments after Percutaneous Nephrolithotomy

    Directory of Open Access Journals (Sweden)

    Kaan Özdedeli

    2012-09-01

    Full Text Available Clinically insignificant residual fragments (CIRFs are described as asymptomatic, noninfectious and nonobstructive stone fragments (≤4 mm remaining in the urinary system after the last session of any intervention (ESWL, URS or PCNL for urinary stones. Their insignificance is questionable since CIRFs could eventually become significant, as their presence may result in recurrent stone growth and they may cause pain and infection due to urinary obstruction. They may become the source of persistent infections and a significant portion of the patients will have a stone-related event, requiring auxilliary interventions. CT seems to be the ultimate choice of assessment. Although there is no concensus about the timing, recent data suggests that it may be performed one month after the procedure. However, imaging can be done in the immediate postoperative period, if there are no tubes blurring the assessment. There is some evidence indicating that selective medical therapy may have an impact on decreasing stone formation rates. Retrograde intrarenal surgery, with its minimally invasive nature, seems to be the best way to deal with residual fragments.

  20. Fragmentation measurement using image processing

    Directory of Open Access Journals (Sweden)

    Farhang Sereshki

    2016-12-01

    Full Text Available In this research, first of all, the existing problems in fragmentation measurement are reviewed for the sake of its fast and reliable evaluation. Then, the available methods used for evaluation of blast results are mentioned. The produced errors especially in recognizing the rock fragments in computer-aided methods, and also, the importance of determination of their sizes in the image analysis methods are described. After reviewing the previous work done, an algorithm is proposed for the automated determination of rock particles’ boundary in the Matlab software. This method can determinate automatically the particles boundary in the minimum time. The results of proposed method are compared with those of Split Desktop and GoldSize software in two automated and manual states. Comparing the curves extracted from different methods reveals that the proposed approach is accurately applicable in measuring the size distribution of laboratory samples, while the manual determination of boundaries in the conventional software is very time-consuming, and the results of automated netting of fragments are very different with the real value due to the error in separation of the objects.

  1. Avian hepatitis E virus, vaccines and methods of protecting against avian hepatitis-splenomegaly syndrome and mammalian hepatitis E

    OpenAIRE

    2009-01-01

    The present invention relates to a novel isolated avian hepatitis E virus having a nucleotide sequence set forth in SEQ ID NO:1 or its complementary strand. The invention further concerns immunogenic compositions comprising this new virus or recombinant products such as the nucleic acid and vaccines that protect an avian or mammalian species from viral infection or hepatitis-splenomegaly syndrome caused by the hepatitis E virus. Also included in the scope of the invention is a method for prop...

  2. Augmenting Tractable Fragments of Abstract Argumentation

    CERN Document Server

    Ordyniak, Sebastian

    2011-01-01

    We present a new and compelling approach to the efficient solution of important computational problems that arise in the context of abstract argumentation. Our approach makes known algorithms defined for restricted fragments generally applicable, at a computational cost that scales with the distance from the fragment. Thus, in a certain sense, we gradually augment tractable fragments. Surprisingly, it turns out that some tractable fragments admit such an augmentation and that others do not. More specifically, we show that the problems of credulous and skeptical acceptance are fixed-parameter tractable when parameterized by the distance from the fragment of acyclic argumentation frameworks. Other tractable fragments such as the fragments of symmetrical and bipartite frameworks seem to prohibit an augmentation: the acceptance problems are already intractable for frameworks at distance 1 from the fragments. For our study we use a broad setting and consider several different semantics. For the algorithmic results...

  3. Self-organized criticality in fragmenting

    DEFF Research Database (Denmark)

    Oddershede, L.; Dimon, P.; Bohr, J.

    1993-01-01

    The measured mass distributions of fragments from 26 fractured objects of gypsum, soap, stearic paraffin, and potato show evidence of obeying scaling laws; this suggests the possibility of self-organized criticality in fragmenting. The probability of finding a fragment scales inversely to a power...

  4. Energy-loss distributions of fission fragments

    Energy Technology Data Exchange (ETDEWEB)

    Demidovich, N.N.; Nakhutin, I.E.; Shatunov, V.G.

    1976-03-05

    The f-f coincidence method was used to investigate the change in the form of the energy-loss distributions of Cf/sup 252/ fission fragments in air, down to fragment energies approx.0.8 MeV. A theoretical model is considered for the estimate of the mean-squared deviations of the fragment energy-loss distributions. (AIP)

  5. Manipulation of male attractiveness induces rapid changes in avian maternal yolk androgen deposition

    NARCIS (Netherlands)

    Kingma, Sjouke A.; Komdeur, Jan; Vedder, Oscar; Engelhardt, Nikolaus von; Korsten, Peter; Groothuis, Ton G.G.

    2009-01-01

    Avian eggs contain maternal androgens that may adjust offspring development to environmental conditions. We review evidence and functional explanations for the relationship between androgen concentrations in avian eggs and male attractiveness. Experimental studies in captive birds show generally pos

  6. [Detection and description of avian hepatitis E virus isolated in China--a review].

    Science.gov (United States)

    Zhao, Qin; Sun, Yani; Zhou, Enmin

    2012-03-04

    Avian hepatitis E virus (HEV), a member of Hepeviridae family, is genetically and antigenically related with human and swine HEV in the family. Since its discovery, avian HEV infection has been investigated in many countries from serology and molecular epidemiology studies. At present, five complete or near complete genomes of avian HEV isolates were reported in GenBank and were divided into three genotypes. The complete genome of avian HEV contains 3 ORFs of which ORF2 gene encodes capsid protein containing the primary epitopes of viral particles and is target gene for serodiagnostic antigen and vaccine candidate. Because avian HEV infection has significant impact on the poultry industry and potential zoonotic transmission, the researches on avian HEV have been given much attention. We here give a broad review of the research update on the aetiology, pathogenesis and the antigenicity of capsid protein of avian HEV based on identification of Chinese avian HEV isolate.

  7. Highly pathogenic avian influenza (HPAI) contingency plan for Rocky Mountain Arsenal NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Disease contingency plan to reduce avian mortality from highly pathogenic avian influenza (HAPI) outbreaks at Rocky Mountain Arsenal National Wildlife Refuge. This...

  8. Isoscaling of projectile-like fragments

    Institute of Scientific and Technical Information of China (English)

    Zhong Chen; Chen Jin-Hui; Guo Wei; Ma Chun-Wang; Ma Guo-Liang; Su Qian-Min; Yan Ting-Zhi; Zuo Jia-Xu; Ma Yu-Gang; Fang De-Qing; Cai Xiang-Zhou; Chen Jin-Gen; Shen Wen-Qing; Tian Wen-Dong; Wang Kun; Wei Yi-Bin

    2006-01-01

    In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragments has been discussed. The isoscaling parameters α andβ have been extracted respectively, for hot fragments before evaporation and cold fragments after evaporation. It looks that the evaporation has stronger effect on α than β. For cold fragments,a monotonic increase of α and |β| with the increase of Z and N is observed. The relation between isoscaling parameter and the change of isospin content is discussed.

  9. Triggered fragmentation in gravitationally unstable discs: forming fragments at small radii

    Directory of Open Access Journals (Sweden)

    Meru Farzana

    2013-04-01

    Full Text Available We carry out three dimensional radiation hydrodynamical simulations of gravitationally unstable discs using to explore the movement of mass in a disc following its fragmentation. Compared to a more quiescent state before it fragments, the radial velocity of the gas increases by up to a factor of ≈ 2 – 3 after fragmentation. While the mass movement occurs both inwards and outwards, the inwards motion can cause the inner spirals to be suciently dense that they may become unstable and potentially fragment. Consequently, the dynamical behaviour of fragmented discs may cause subsequent fragmentation at smaller radii after an initial fragment has formed in the outer disc.

  10. Impact of numerical models on fragmentation processes

    Science.gov (United States)

    Renouf, Mathieu; Gezahengn, Belien; Abbas, Micheline; Bourgeois, Florent

    2013-06-01

    Simulated fragmentation process in granular assemblies is a challenging problem which date back the beginning of the 90'. If first approaches have focus on the fragmentation on a single particle, with the development of robust, fast numerical method is is possible today to simulated such process in a large collection of particles. But the question of the fragmentation problem is still open: should the fragmentation be done dynamically (one particle becoming two fragments) and according which criterion or should the fragment paths be defined initially and which is the impact of the discretization and the model of fragments? The present contribution proposes to investigate the second aspect i.e. the impact of fragment modeling on the fragmentation processes. First to perform such an analysis, the geometry of fragments (disks/sphere or polygon/polyhedra), their behavior (rigid/deformable) and the law governing their interactions are investigated. Then such model will be used in a grinding application where the evolution of fragments and impact on the behavior of the whole packing are investigate.

  11. Dihadron Fragmentation Functions and Transversity

    Directory of Open Access Journals (Sweden)

    Radici Marco

    2015-01-01

    Full Text Available We present preliminary results for an updated extraction of the transversity parton distribution based on the analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets in collinear factorization. Data for proton and deuteron targets by HERMES and COMPASS allow for a flavor separation of the valence components of transversity, while di-hadron fragmentation functions are taken from the semi-inclusive production of two pion pairs in back-to-back jets in e+e− annihilation. The latter data from Belle have been reanalyzed using the replica method and a more realistic estimate of the uncertainties on the chiral-odd interference fragmentation function has been obtained. After encoding this piece of information into the deep-inelastic scattering cross section, the transversity has been re-extracted by using the most recent and more precise COMPASS data for proton target. This picture represents the current most realistic estimate of the uncertainties on our knowledge of transversity. The preliminary results indicate that the valence up component seems smaller and with a narrower error band than in previous extraction.

  12. Dihadron Fragmentation Functions and Transversity

    CERN Document Server

    Radici, Marco; Bacchetta, Alessandro

    2014-01-01

    We present preliminary results for an updated extraction of the transversity parton distribution based on the analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets in collinear factorization. Data for proton and deuteron targets by HERMES and COMPASS allow for a flavor separation of the valence components of transversity, while di-hadron fragmentation functions are taken from the semi-inclusive production of two pion pairs in back-to-back jets in $e^+ e^-$ annihilation. The latter data from Belle have been reanalyzed using the replica method and a more realistic estimate of the uncertainties on the chiral-odd interference fragmentation function has been obtained. After encoding this piece of information into the deep-inelastic scattering cross section, the transversity has been re-extracted by using the most recent and more precise COMPASS data for proton target. This picture represents the current most realistic estimate of the uncertainties on our knowledge of tran...

  13. The formation of planets by disc fragmentation

    Directory of Open Access Journals (Sweden)

    Stamatellos Dimitris

    2013-04-01

    Full Text Available I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar discs may fragment, if they are massive enough and can cool fast enough, but most of the objects that form by fragmentation are brown dwarfs. It may be possible that planets also form, if the mass growth of a proto-fragment is stopped (e.g. if this fragment is ejected from the disc, or suppressed and even reversed (e.g by tidal stripping. I will discuss if it is possible to distinguish whether a planet has formed by disc fragmentation or core accretion, and mention of a few examples of observed exoplanets that are suggestive of formation by disc fragmentation.

  14. Reframing landscape fragmentation's effects on ecosystem services.

    Science.gov (United States)

    Mitchell, Matthew G E; Suarez-Castro, Andrés F; Martinez-Harms, Maria; Maron, Martine; McAlpine, Clive; Gaston, Kevin J; Johansen, Kasper; Rhodes, Jonathan R

    2015-04-01

    Landscape structure and fragmentation have important effects on ecosystem services, with a common assumption being that fragmentation reduces service provision. This is based on fragmentation's expected effects on ecosystem service supply, but ignores how fragmentation influences the flow of services to people. Here we develop a new conceptual framework that explicitly considers the links between landscape fragmentation, the supply of services, and the flow of services to people. We argue that fragmentation's effects on ecosystem service flow can be positive or negative, and use our framework to construct testable hypotheses about the effects of fragmentation on final ecosystem service provision. Empirical efforts to apply and test this framework are critical to improving landscape management for multiple ecosystem services.

  15. Development and application of an RT-PCR test for detecting avian nephritis virus.

    Science.gov (United States)

    Todd, D; Trudgett, J; McNeilly, F; McBride, N; Donnelly, B; Smyth, V J; Jewhurst, H L; Adair, B M

    2010-06-01

    The development of a reverse transcriptase-polymerase chain reaction (RT-PCR) test for detecting avian nephritis virus (ANV) is described. Primers, which amplified a fragment of 182 base pairs (bp), were located in the conserved 3' untranslated region (UTR) of the genome. The limit of detection of the test was estimated to be approximately 18 viral copies using a 10-fold dilution series of in vitro transcribed RNA. Positive signals were produced with representative ANV samples, some of which were not detected by previously described RT-PCR tests for detecting ANV, but other avian astroviruses including chicken astrovirus isolates and duck hepatitis virus types 2 and 3 tested negative. When applied to gut content samples from UK, German and US broiler flocks with enteritis/growth problems, ANVs were detected by RT-PCR in 82/82 (100%) samples. ANVs were also detected in 80/96 (83%) pooled gut content samples from longitudinal surveys of four broiler flocks displaying below-average performance. Whereas all samples collected on day 0 from the surveys were negative for ANV, all samples collected at days 4/5, 7, 10, 14, 21 and 28 tested positive. Sequence determinations performed with amplicons produced with 14 field samples confirmed the ANV specificity of the test, while comparative and phylogenetic analyses based on 109-nucleotide 3'-UTR sequences demonstrated that the majority of ANVs investigated were more closely related to the serotype 2 ANV (accession number AB 046864) than to the serotype 1 ANV (accession number NC 003790).

  16. 76 FR 67017 - Notice to Manufacturers of Airport Avian Radar Systems

    Science.gov (United States)

    2011-10-28

    ... Federal Aviation Administration Notice to Manufacturers of Airport Avian Radar Systems AGENCY: Federal Aviation Administration (FAA), U.S. DOT. ACTION: Notice to Manufacturers of Airport Avian Radar Systems... waivers to foreign manufacturers of airport avian radar systems that meet the requirements of FAA...

  17. 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...

  18. Planning and executing a vaccination campaign against avian influenza.

    Science.gov (United States)

    Marangon, S; Cristalli, A; Busani, L

    2007-01-01

    Vaccination against avian influenza infection caused by H5 or H7 virus subtypes has been used on several occasions in recent years to control and in some cases eradicate the disease. In order to contain avian influenza infection effectively, immunization should be combined with a coordinated set of control and monitoring measures. The outcome of an immunization campaign depends on the territorial strategy; whereas the capacity of the veterinary services in developed countries permits enforcement of strategies aimed at eradicating avian influenza, many countries currently affected by highly pathogenic avian influenza (HPAI) H5N1 viruses have a limited veterinary infrastructure and a limited capacity to respond to such epidemics. In these countries, resources are still insufficient to conduct adequate surveillance for identification and reaction to avian influenza outbreaks when they occur. When properly applied in this scenario, immunization can reduce mortality and production losses. In the long term, immunization might also decrease the prevalence of infection to levels at which stamping-out and surveillance can be applied. Countries should adapt their immunization programmes to local conditions in order to guarantee their efficacy and sustainability. In the initial emergency phase, human resources can be mobilized, with reliance on personal responsibility and motivation, thus compensating for potential shortcomings in organization. A more appropriate allocation of resources must be pursued in the long term, remembering that biosecurity is the main component of an exit strategy and must always be improved.

  19. Avian influenza survey in migrating waterfowl in Sonora, Mexico.

    Science.gov (United States)

    Montalvo-Corral, M; López-Robles, G; Hernández, J

    2011-02-01

    A two-year survey was carried out on the occurrence of avian influenza in migrating birds in two estuaries of the Mexican state of Sonora, which is located within the Pacific flyway. Cloacal and oropharyngeal swabs were collected from 1262 birds, including 20 aquatic bird species from the Moroncarit and Tobari estuaries in Sonora, Mexico. Samples were tested for type A influenza (M), H5 Eurasian and North American subtypes (H5EA and H5NA respectively) and the H7 North American subtype (H7NA). Gene detection was determined by one-step real-time reverse transcription polymerase chain reaction (RRT-PCR). The results revealed that neither the highly pathogenic avian influenza virus H5 of Eurasian lineage nor H7NA were detected. The overall prevalence of avian influenza type A (M-positive) in the sampled birds was 3.6% with the vast majority in dabbling ducks (Anas species). Samples from two birds, one from a Redhead (Aythya americana) and another from a Northern Shoveler (Anas clypeata), were positive for the low-pathogenic H5 avian influenza virus of North American lineage. These findings represented documented evidence of the occurrence of avian influenza in wintering birds in the Mexican wetlands. This type of study contributes to the understanding of how viruses spread to new regions of North America and highlights the importance of surveillance for the early detection and control of potentially pathogenic strains, which could affect animal and human health.

  20. 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.

  1. Exploring the avian gut microbiota: current trends and future directions

    Directory of Open Access Journals (Sweden)

    David William Waite

    2015-07-01

    Full Text Available Birds represent a diverse and evolutionarily successful lineage, occupying a wide range of niches throughout the world. Like all vertebrates, avians harbour diverse communities of microorganisms within their guts, which collectively fulfil crucial roles in providing the host with nutrition and protection from pathogens. Across the field of avian microbiology knowledge is extremely uneven, with several species accounting for an overwhelming majority of all microbiological investigations. These include agriculturally important birds, such as chickens and turkeys, as well as birds of evolutionary or conservation interest. In our previous study we attempted the first meta-analysis of the avian gut microbiota, using 16S rRNA gene sequences obtained from a range of publicly available data sets. We have now extended our analysis to explore the microbiology of several key species in detail, to consider the avian microbiota within the context of what is known about other vertebrates, and to identify key areas of interest in avian microbiology for future study.

  2. Research progress in avian dispersal behavior

    Institute of Scientific and Technical Information of China (English)

    Yang LIU; Zhengwang ZHANG

    2008-01-01

    Dispersal, defined as a linear spreading move-ment of individuals away from others of the population is a fundamental characteristic of organisms in nature. Dispersal is a central concept in ecological, behavioral and evolutionary studies, driven by different forces such as avoidance of inbreeding depression, density-dependent competition and the need to change breeding locations. By effective dispersal, organisms can enlarge their geo-graphic range and adjust the dynamic, sex ratio and gen-etic compositions of a population. Birds are one of the groups that are studied intensively by human beings. Due to their diurnal habits, diverse life history strategies and complex movement, birds are also ideal models for the study of dispersal behaviors. Certain topics of avian dispersal including sex-biased, asymmetric dispersal caused by differences in body conditions, dispersal pro-cesses, habitat selection and long distance dispersal are discussed here. Bird-ringing or marking, radio-telemetry and genetic markers are useful tools widely applied in dispersal studies. There are three major challenges regard-ing theoretical study and methodology research of dis-persal: (1) improvement in research methodology is needed, (2) more in-depth theoretical research is neces-sary, and (3) application of theoretical research into the conservation efforts for threatened birds and the manage-ment of their habitats should be carried out immediately.

  3. 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.

  4. Avian Influenza: Mixed Infections and Missing Viruses

    Directory of Open Access Journals (Sweden)

    David E. Wentworth

    2013-08-01

    Full Text Available A high prevalence and diversity of avian influenza (AI viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  5. What's missing from avian global diversification analyses?

    Science.gov (United States)

    Reddy, Sushma

    2014-08-01

    The accumulation of vast numbers of molecular phylogenetic studies has contributed to huge knowledge gains in the evolutionary history of birds. This permits subsequent analyses of avian diversity, such as how and why diversification varies across the globe and among taxonomic groups. However, available genetic data for these meta-analyses are unevenly distributed across different geographic regions and taxonomic groups. To comprehend the impact of this variation on the interpretation of global diversity patterns, I examined the availability of genetic data for possible biases in geographic and taxonomic sampling of birds. I identified three main disparities of sampling that are geographically associated with latitude (temperate, tropical), hemispheres (East, West), and range size. Tropical regions, which host the vast majority of species, are substantially less studied. Moreover, Eastern regions, such as the Old World Tropics and Australasia, stand out as being disproportionately undersampled, with up to half of communities not being represented in recent studies. In terms of taxonomic discrepancies, a majority of genetically undersampled clades are exclusively found in tropical regions. My analysis identifies several disparities in the key regions of interest of global diversity analyses. Differential sampling can have considerable impacts on these global comparisons and call into question recent interpretations of latitudinal or hemispheric differences of diversification rates. Moreover, this review pinpoints understudied regions whose biota are in critical need of modern systematic analyses.

  6. Avian influenza: mixed infections and missing viruses.

    Science.gov (United States)

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

    2013-08-05

    A high prevalence and diversity of avian influenza (AI) viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA) gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes) were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.

  7. Molecular characteristics and pathogenicity of an avian leukosis virus isolated from avian neurofibrosarcoma.

    Science.gov (United States)

    Ochi, Akihiro; Ochiai, Kenji; Nakamura, Sayuri; Kobara, Akiko; Sunden, Yuji; Umemura, Takashi

    2012-03-01

    Peripheral nerve sheath tumors (PNSTs) are rare in chickens and their etiology remains to be elucidated. In this study, a naturally occurring PNST in a Japanese native fowl (Gallus gallus domesticus) was pathologically examined and the strain of avian leukosis virus (ALV) isolated from the neoplasm was characterized by molecular biological analysis. The fowl presented with a firm subcutaneous mass in the neck. The mass, connected to the adjacent spinal cord (C9-14), was microscopically composed of highly cellular tissue of spindle cells arranged in interlacing bundles, streams, and palisading patterns with Verocay bodies and less cellular tissue with abundant collagen. Immunohistochemically, neoplastic cells were divided into two types: perineurial cells positive for vimentin, glucose transporter 1 (GLUT1), and claudin1; and Schwann cells positive for vimentin, occasionally positive for S-100 alpha/beta but negative for GLUT1. Based on these findings, a diagnosis of neurofibrosarcoma was made. The complete nucleotide sequence of an ALV strain, CTS_5371, isolated from the neoplasm was determined and phylogenetic analysis indicated that the strain was a novel recombinant virus from avian leukosis/sarcoma viruses previously reported. Additionally, experimental infection revealed that CTS_5371 induced the proliferation of Schwann cells and perineurial cells. These results suggest that this ALV strain has the ability to induce PNSTs in chickens.

  8. Evidence of widespread infection of avian hepatitis E virus (avian HEV) in chickens from Spain.

    Science.gov (United States)

    Peralta, Bibiana; Biarnés, Mar; Ordóñez, Germán; Porta, Ramón; Martín, Marga; Mateu, Enric; Pina, Sonia; Meng, Xiang-Jin

    2009-05-28

    In the present work, 262 serum samples and 29 faeces pools from chickens coming from 29 healthy flocks were analysed by RT-PCR for detection of avian HEV and by ELISA using an aHEV derived antigen for detection of anti-HEV IgG. Additionally, other 300 randomly selected serum samples were also analysed by RT-PCR. Seven serum samples were positive to RNA detection. Sequence analysis of both the helicase and the capsid genes revealed that the Spanish isolates were clustered together and close related to those strains from the United States isolated from farms with HSS. On the serology study, 26/29 flocks had at least one positive animal (89.7%) and chickens older than 40 weeks were found to have higher seropositivities compared to the rest of age groups. Within positive farms, the proportion of positive animals ranged from 20% to 80%. This is the first report of aHEV sequences in chickens from Europe. Further studies are needed to elucidate the clinical significance of avian HEV infections in Europe.

  9. The avian and mammalian host range of highly pathogenic avian H5N1 influenza.

    Science.gov (United States)

    Kaplan, Bryan S; Webby, Richard J

    2013-12-05

    Highly pathogenic H5N1 influenza viruses have been isolated from a number of avian and mammalian species. Despite intensive control measures the number of human and animal cases continues to increase. A more complete understanding of susceptible species and of contributing environmental and molecular factors is crucial if we are to slow the rate of new cases. H5N1 is currently endemic in domestic poultry in only a handful of countries with sporadic and unpredictable spread to other countries. Close contact of terrestrial bird or mammalian species with infected poultry/waterfowl or their biological products is the major route for interspecies transmission. Intra-species transmission of H5N1 in mammals, including humans, has taken place on a limited scale though it remains to be seen if this will change; recent laboratory studies suggest that it is indeed possible. Here we review the avian and mammalian species that are naturally susceptible to H5N1 infection and the molecular factors associated with its expanded host range.

  10. Identification of B-cell epitopes in the capsid protein of avian hepatitis E virus (avian HEV) that are common to human and swine HEVs or unique to avian HEV.

    Science.gov (United States)

    Guo, H; Zhou, E-M; Sun, Z F; Meng, X-J; Halbur, P G

    2006-01-01

    Avian hepatitis E virus (avian HEV) was recently discovered in chickens from the USA that had hepatitis-splenomegaly (HS) syndrome. The complete genomic sequence of avian HEV shares about 50 % nucleotide sequence identity with those of human and swine HEVs. The open reading frame 2 (ORF2) protein of avian HEV has been shown to cross-react with human and swine HEV ORF2 proteins, but the B-cell epitopes in the avian HEV ORF2 protein have not been identified. Nine synthetic peptides from the predicted four antigenic domains of the avian HEV ORF2 protein were synthesized and corresponding rabbit anti-peptide antisera were generated. Using recombinant ORF2 proteins, convalescent pig and chicken antisera, peptides and anti-peptide rabbit sera, at least one epitope at the C terminus of domain II (possibly between aa 477-492) that is unique to avian HEV, one epitope in domain I (aa 389-410) that is common to avian, human and swine HEVs, and one or more epitopes in domain IV (aa 583-600) that are shared between avian and human HEVs were identified. Despite the sequence difference in ORF2 proteins between avian and mammalian HEVs and similar ORF2 sequence between human and swine HEV ORF2 proteins, rabbit antiserum against peptide 6 (aa 389-399) recognized only human HEV ORF2 protein, suggesting complexity of the ORF2 antigenicity. The identification of these B-cell epitopes in avian HEV ORF2 protein may be useful for vaccine design and may lead to future development of immunoassays for differential diagnosis of avian, swine and human HEV infections.

  11. Natural Infection with Avian Hepatitis E Virus and Marek's Disease Virus in Brown Layer Chickens in China.

    Science.gov (United States)

    Yang, Shuqing; Wang, Liyuan; Sun, Shuhong

    2016-09-01

    In the present study, avian hepatitis E virus (HEV) and serotype-1 strains of Marek's disease virus (MDV-1) were detected from a flock of 27-wk-old brown layer hens in China, accompanied by an average daily mortality of 0.44%. Postmortem examination of 25 sick hens and five apparently healthy hens selected randomly from the flock showed significant pathologic changes consistent with hepatitis-splenomegaly syndrome (HSS), including hepatomegaly, peritoneal fluid, and hepatic subcapsular hemorrhages. Microscopic examination of these livers showed multifocal necrotizing hepatitis and mild lymphocytic infiltration. These liver samples were investigated for HEV by reverse-transcription PCR. The overall detection rate of HEV RNA in samples of sick chickens was about 56% (14/25), while in samples from apparently healthy hens, it was 80% (4/5). Sequencing analysis of three 242-base-pair fragments of the helicase gene revealed 95.5% to 97.9% nucleotide identity compared with published avian HEV genotype 3, whereas identities demonstrated only 77.3% to 86.0% similarity when compared with genotypes 1, 2, and 4. Unexpectedly, the MDV meq gene was detected in livers from both apparently healthy chickens (2/5) and sick chickens (12/25) by PCR analysis. The meq gene (396 base pairs) was determined to belong to MDV-1 by further sequencing. The co-infection rate of avian HEV and MDV in this flock was 30% (9/30). This is the first report of dual infection of a nonenvelope RNA virus (HEV) with a herpesvirus (MDV) in chickens in China.

  12. Single chain Fab (scFab fragment

    Directory of Open Access Journals (Sweden)

    Brenneis Mariam

    2007-03-01

    Full Text Available Abstract Background The connection of the variable part of the heavy chain (VH and and the variable part of the light chain (VL by a peptide linker to form a consecutive polypeptide chain (single chain antibody, scFv was a breakthrough for the functional production of antibody fragments in Escherichia coli. Being double the size of fragment variable (Fv fragments and requiring assembly of two independent polypeptide chains, functional Fab fragments are usually produced with significantly lower yields in E. coli. An antibody design combining stability and assay compatibility of the fragment antigen binding (Fab with high level bacterial expression of single chain Fv fragments would be desirable. The desired antibody fragment should be both suitable for expression as soluble antibody in E. coli and antibody phage display. Results Here, we demonstrate that the introduction of a polypeptide linker between the fragment difficult (Fd and the light chain (LC, resulting in the formation of a single chain Fab fragment (scFab, can lead to improved production of functional molecules. We tested the impact of various linker designs and modifications of the constant regions on both phage display efficiency and the yield of soluble antibody fragments. A scFab variant without cysteins (scFabΔC connecting the constant part 1 of the heavy chain (CH1 and the constant part of the light chain (CL were best suited for phage display and production of soluble antibody fragments. Beside the expression system E. coli, the new antibody format was also expressed in Pichia pastoris. Monovalent and divalent fragments (DiFabodies as well as multimers were characterised. Conclusion A new antibody design offers the generation of bivalent Fab derivates for antibody phage display and production of soluble antibody fragments. This antibody format is of particular value for high throughput proteome binder generation projects, due to the avidity effect and the possible use of

  13. Nonlinear Inflaton Fragmentation after Preheating

    CERN Document Server

    Felder, G N; Felder, Gary N.; Kofman, Lev

    2007-01-01

    We consider the nonlinear dynamics of inflaton fragmentation during and after preheating in the simplest model of chaotic inflation. While the earlier regime of parametric resonant particle production and the later turbulent regime of interacting fields evolving towards equilibrium are well identified and understood, the short intermediate stage of violent nonlinear dynamics remains less explored. Lattice simulations of fully nonlinear preheating dynamics show specific features of this intermediate stage: occupation numbers of the scalar particles are peaked, scalar fields become significantly non-gaussian and the field dynamics become chaotic and irreversible. Visualization of the field dynamics in configuration space reveals that nonlinear interactions generate non-gaussian inflaton inhomogeneities with very fast growing amplitudes. The peaks of the inflaton inhomogeneities coincide with the peaks of the scalar field(s) produced by parametric resonance. When the inflaton peaks reach their maxima, they stop ...

  14. Fluid fragmentation from hospital toilets

    CERN Document Server

    Traverso, G; Lu, C -C; Maa, R; Langer, R; Bourouiba, L

    2013-01-01

    Hospital-acquired infections represent significant health and financial burdens to society. Clostridium difficile (C. difficile) is a particularly challenging bacteria with the potential to cause severe diarrhea and death. One mode of transmission for C. difficile, as well as other pathogens, which has received little attention is the potential air contamination by pathogen-bearing droplets emanating from toilets. In the fluid dynamics video submitted to the APS DFD Gallery of Fluid Motion 2013, we present flow visualizations via high-speed recordings showing the capture of the product of the fluid fragmentation generated by hospital toilet high-pressure flushes. Important quantities of both large and small droplets are observed. We illustrate how high-pressure flushes and cleaning products currently used in hospital toilets result in aggravating, rather than alleviating, the suspension and recirculation of tenacious airborne pathogen-bearing droplets.

  15. Fragmentation in Carbon Therapy Beams

    CERN Document Server

    Charara, Y M

    2010-01-01

    The state of the art Monte Carlo code HETC-HEDS was used to simulate spallation products, secondary neutron, and secondary proton production in A-150 Tissue Equivalent Plastic phantoms to investigate fragmentation of carbon therapy beams. For a 356 MeV/Nucleon carbon ion beam, production of charged particles heavier than protons was 0.24 spallation products per incident carbon ion with atomic numbers ranging from 1 through 5 (hydrogen to boron). In addition, there were 4.73 neutrons and 2.95 protons produced per incident carbon ion. Furthermore, as the incident energy increases, the neutron production rate increases at a rate of 20% per 10 MeV/nucleon. Secondary protons were created at a rate between 2.62-2.87 per carbon ion, while spallation products were created at a rate between 0.20-0.24 per carbon ion.

  16. Avians as a model system of vascular development.

    Science.gov (United States)

    Bressan, Michael; Mikawa, Takashi

    2015-01-01

    For more than 2,000 years, philosophers and scientists have turned to the avian embryo with questions of how life begins (Aristotle and Peck Generations of Animals. Loeb Classics, vol. XIII. Harvard University Press, Cambridge, 1943; Needham, A history of embryology. Abelard-Schuman, New York, 1959). Then, as now, the unique accessibility of the embryo both in terms of acquisition of eggs from domesticated fowl and ease at which the embryo can be visualized by simply opening the shell has made avians an appealing and powerful model system for the study of development. Thus, as the field of embryology has evolved through observational, comparative, and experimental embryology into its current iteration as the cellular and molecular biology of development, avians have remained a useful and practical system of study.

  17. Avian influenza surveillance in backyard poultry of Argentina.

    Science.gov (United States)

    Buscaglia, C; Espinosa, C; Terrera, M V; De Benedetti, R

    2007-03-01

    Avian influenza (AI) is an exotic disease in Argentina. A surveillance program for AI was conducted in backyard poultry during 1998-2005 in two regions: 1) region A, which included the avian population in the provinces that border Brazil, Bolivia, and Paraguay, and 2) region B, which included the rest of the provinces of the country. More than 8000 serum samples were tested for antibodies by enzyme-linked immunosorbent assay and/or agar gel immunodiffusion tests, and more than 18,000 tracheal and cloacal swabs were tested for virus by isolation in embryonated specific-pathogen-free eggs. This study was part of the AI prevention program in Argentina, which includes other avian populations such as commercial poultry and all the controls for importation and exportation of live birds. The results from backyard poultry were negative for AI.

  18. Protecting poultry workers from exposure to avian influenza viruses.

    Science.gov (United States)

    MacMahon, Kathleen L; Delaney, Lisa J; Kullman, Greg; Gibbins, John D; Decker, John; Kiefer, Max J

    2008-01-01

    Emerging zoonotic diseases are of increasing regional and global importance. Preventing occupational exposure to zoonotic diseases protects workers as well as their families, communities, and the public health. Workers can be protected from zoonotic diseases most effectively by preventing and controlling diseases in animals, reducing workplace exposures, and educating workers. Certain avian influenza viruses are potential zoonotic disease agents that may be transmitted from infected birds to humans. Poultry workers are at risk of becoming infected with these viruses if they are exposed to infected birds or virus-contaminated materials or environments. Critical components of worker protection include educating employers and training poultry workers about occupational exposure to avian influenza viruses. Other recommendations for protecting poultry workers include the use of good hygiene and work practices, personal protective clothing and equipment, vaccination for seasonal influenza viruses, antiviral medication, and medical surveillance. Current recommendations for protecting poultry workers from exposure to avian influenza viruses are summarized in this article.

  19. Antigenic properties of avian hepatitis E virus capsid protein.

    Science.gov (United States)

    Zhao, Qin; Syed, Shahid Faraz; Zhou, En-Min

    2015-10-22

    Avian hepatitis E virus (HEV) is the main causative agent of big liver and spleen disease and hepatitis-splenomegaly syndrome in chickens, and is genetically and antigenically related to mammalian HEVs. HEV capsid protein contains immunodominant epitopes and induces a protective humoral immune response. A better understanding of the antigenic composition of this protein is critically important for the development of effective vaccine and sensitive and specific serological assays. To date, six linear antigenic domains (I-VI) have been characterized in avian HEV capsid protein and analyzed for their applications in the serological diagnosis and vaccine design. Domains I and V induce strong immune response in chickens and are common to avian, human, and swine HEVs, indicating that the shared epitopes hampering differential diagnosis of avian HEV infection. Domains III and IV are not immunodominant and elicit a weak immune response. Domain VI, located in the N-terminal region of the capsid protein, can also trigger an intense immune response, but the anti-domain VI antibodies are transient. The protection analysis showed that the truncated capsid protein containing the C-terminal 268 amino acid residues expressed by the bacterial system can provide protective immunity against avian HEV infection in chickens. However, the synthetic peptides incorporating the different linear antigenic domains (I-VI) and epitopes are non-protective. The antigenic composition of avian HEV capsid protein is altogether complex. To develop an effective vaccine and accurate serological diagnostic methods, more conformational antigenic domains or epitopes are to be characterized in detail.

  20. Absence of avian pox in wild turkeys in central Mississippi.

    Science.gov (United States)

    Couvillion, C E; Stacey, L M; Hurst, G A

    1991-07-01

    Eastern wild turkeys (Meleagris gallopavo silvestris) (n = 1,023), obtained during winter, spring, and summer from 1983 to 1988 on Tallahala Wildlife Management Area (TWMA) (Jasper County, Mississippi, USA) were examined for avian pox lesions. Domestic turkey poults (n = 152) maintained on the area for 1 to 2 wk periods from 1987 to 1989 also were examined. Neither wild nor domestic birds showed gross evidence of pox virus infection. This study indicated that avian pox was not endemic in wild turkeys at TWMA.

  1. A simplified method for extracting androgens from avian egg yolks

    Science.gov (United States)

    Kozlowski, C.P.; Bauman, J.E.; Hahn, D.C.

    2009-01-01

    Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl.

  2. Comparative genomic data of the Avian Phylogenomics Project

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Bo; Li, Cai;

    2014-01-01

    , which include 38 newly sequenced avian genomes plus previously released or simultaneously released genomes of Chicken, Zebra finch, Turkey, Pigeon, Peregrine falcon, Duck, Budgerigar, Adelie penguin, Emperor penguin and the Medium Ground Finch. We hope that this resource will serve future efforts...... in an average N50 scaffold size of about 50 kb. Repetitive elements comprised 4%-22% of the bird genomes. The assembled scaffolds allowed the homology-based annotation of 13,000 ~ 17000 protein coding genes in each avian genome relative to chicken, zebra finch and human, as well as comparative and sequence...

  3. Teaching avian patients and caregivers in the examination room.

    Science.gov (United States)

    Cook, Ellen K

    2012-09-01

    Client education and patient well-being should be primary goals and responsibilities for practicing avian veterinarians. Time is limited in the normal clinical appointment setting. However, this opportunity can still be used to introduce clients to the basics of training with positive reinforcement. These methods build a healthy relationship of trust between caregivers and their birds. Within the allotted appointment time, it is possible to teach clients how to train a simple behavior. This article outlines and demonstrates how training avian patients is successfully applied in a typical clinical practice.

  4. Sensitivity and entanglement in the avian chemical compass

    Science.gov (United States)

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

    2014-10-01

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

  5. Sensitivity and Entanglement in the Avian Chemical Compass

    CERN Document Server

    Zhang, Yiteng; Kais, Sabre

    2014-01-01

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

  6. The challenges of avian influenza virus: mechanism, epidemiology and control

    Institute of Scientific and Technical Information of China (English)

    George F. GAO; Pang-Chui SHAW

    2009-01-01

    @@ Early 2009, eight human infection cases of H5N1 highly pathogenic avian influenza (HPAI) virus, with 5 death cases, were reported in China. This again made the world alert on a possible pandemic worldwide, probably caused by avian-origin influenza virus. Again H5N1 is in the spotlight of the world, not only for the scientists but also for the ordinary people. How much do we know about this virus? Where will this virus go and where did it come? Can we avoid a possible pandemic of influenza? Will the human beings conquer this devastating agent? Obviously we can list more questions than we know the answers.

  7. 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.

  8. Microbes of the avian cecum: types present and substrates utilized.

    Science.gov (United States)

    Mead, G C

    1989-01-01

    This paper discusses the types and properties of microorganisms found in avian ceca, with special reference to the chicken. Microbial activity in the cecum is primarily fermentative, but there has been little evidence of cellulose fermentation, and the predominant bacterial types are relatively inactive against other high-molecular-weight compounds of dietary origin. In all avian species examined, the consistent presence of large populations of uric acid-degrading bacteria supports the view that microbial populations in the ceca permit reabsorption of water and possibly nonprotein nitrogen from the backflow of urine. These capabilities may be of particular importance to wild birds under conditions of water and food deprivation.

  9. Construction of an infectious cDNA clone of avian hepatitis E virus (avian HEV) recovered from a clinically healthy chicken in the United States and characterization of its pathogenicity in specific-pathogen-free chickens

    OpenAIRE

    Kwon, Hyuk Moo; LeRoith, Tanya; Pudupakam, R. S.; Pierson, F. William; Huang, Yao-Wei; Dryman, Barbara A.; Meng, Xiang-Jin

    2010-01-01

    A genetically distinct strain of avian hepatitis E virus (avian HEV-VA strain) was isolated from a healthy chicken in Virginia, and thus it is important to characterize and compare its pathogenicity with the prototype strain (avian HEV-prototype) isolated from a diseased chicken. Here we first constructed an infectious clone of the avian HEV-VA strain. Capped RNA transcripts from the avian HEV-VA clone were replication-competent after transfection of LMH chicken liver cells. Chickens inoculat...

  10. Coal char fragmentation during pulverized coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L.

    1995-07-01

    A series of investigations of coal and char fragmentation during pulverized coal combustion is reported for a suite of coals ranging in rank from lignite to low-volatile (lv) bituminous coal under combustion conditions similar to those found in commercial-scale boilers. Experimental measurements are described that utilize identical particle sizing characteristics to determine initial and final size distributions. Mechanistic interpretation of the data suggest that coal fragmentation is an insignificant event and that char fragmentation is controlled by char structure. Chars forming cenospheres fragment more extensively than solid chars. Among the chars that fragment, large particles produce more fine material than small particles. In all cases, coal and char fragmentation are seen to be sufficiently minor as to be relatively insignificant factors influencing fly ash size distribution, particle loading, and char burnout.

  11. 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.

  12. 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.

  13. Generation and characterization of chicken-sourced single-chain variable fragments (scFvs) against porcine interferon-gamma (pIFN-γ).

    Science.gov (United States)

    Chen, Hong-Xiu; He, Fan; Sun, Yuan; Luo, Yuzi; Qiu, Hua-Ji; Zhang, Xiao-Ying; Sutton, Brian J

    2015-01-01

    Development of chicken-sourced antibodies offers an alternative strategy for the development of highly specific antibodies against mammalian proteins with conserved epitopes due to the phylogenetic distance between avian and mammalian species. In this study, the single-chain variable fragments (scFvs) against porcine interferon-gamma was screened and characterized from a hyperimmunized chicken phage display library. The expressed soluble scFvs exhibited highly specific recognition of porcine interferon-gamma in ELISA, Western blot, and immunofluorescence staining assays. Results of the current study indicate that it is possible to develop scFv IgY antibodies to a mammalian interferon by using Biopanning technology. Furthermore, it also confirms that monoclonal avian IgY antibody technique could be applied as a promising tool to produce immunoglobulin molecules with high specificity and affinity towards conserved mammalian epitopes or antigens.

  14. A Note on Convex Renorming and Fragmentability

    Indian Academy of Sciences (India)

    A K Mirmostafaee

    2005-05-01

    Using the game approach to fragmentability, we give new and simpler proofs of the following known results: (a) If the Banach space admits an equivalent Kadec norm, then its weak topology is fragmented by a metric which is stronger than the norm topology. (b) If the Banach space admits an equivalent rotund norm, then its weak topology is fragmented by a metric. (c) If the Banach space is weakly locally uniformly rotund, then its weak topology is fragmented by a metric which is stronger than the norm topology.

  15. Heterogeneity and Seroprevalence of a Newly Identified Avian Hepatitis E Virus from Chickens in the United States

    OpenAIRE

    Huang, F. F.; Haqshenas, G.; Shivaprasad, H L; Guenette, D. K.; Woolcock, P. R.; Larsen, C. T.; Pierson, F.W.; F Elvinger; Toth, T. E.; Meng, X. J.

    2002-01-01

    We recently identified and characterized a novel virus, designated avian hepatitis E virus (avian HEV), from chickens with hepatitis-splenomegaly syndrome (HS syndrome) in the United States. Avian HEV is genetically related to but distinct from human and swine HEVs. To determine the extent of genetic variation and the seroprevalence of avian HEV infection in chicken flocks, we genetically identified and characterized 11 additional avian HEV isolates from chickens with HS syndrome and assessed...

  16. Entomological study on transmission of avian malaria parasites in a zoological garden in Japan: bloodmeal identification and detection of avian malaria parasite DNA from blood-fed mosquitoes.

    Science.gov (United States)

    Ejiri, Hiroko; Sato, Yukita; Kim, Kyeong-Soon; Hara, Tatsuko; Tsuda, Yoshio; Imura, Takayuki; Murata, Koichi; Yukawa, Masayoshi

    2011-05-01

    Several species of captive and wild birds have been found to be infected with various avian blood protozoa in Japan. We investigated the prevalence and transmission of avian malaria parasite and determined the bloodmeal hosts of mosquitoes collected in a zoological garden in Tokyo, Japan, by using the polymerase chain reaction. In total, 310 unfed and 140 blood-fed mosquitoes of seven species were collected by using sweep nets and CDC traps. Bloodmeal identification indicated that mosquitoes had fed on 17 avian and five mammalian species, including captive animals. The results of avian malaria parasite detection from mosquitoes with avian bloodmeals indicated that Culex pipiens pallens Coquillet is a main vector of avian Plasmodium in the current study site and that some captive and wild birds could be infected with avian malaria parasites. Furthermore, the distances between the collection site of blood-fed mosquitoes and the locations of their blood-source captive animals were estimated. Most females with fresh bloodmeals were found within 40 m of caged animals, whereas half-gravid and gravid females were found between 10 and 350 m from caged host animals. We demonstrated that blood-fed mosquitoes can provide useful information regarding the mosquito vector species of avian malaria parasites and allows for noninvasive detection of the presence of avian malaria parasites in bird populations.

  17. Gene duplication and fragmentation in the zebra finch major histocompatibility complex

    Directory of Open Access Journals (Sweden)

    Burt David W

    2010-04-01

    Full Text Available Abstract Background Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. Results The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. Conclusion The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving

  18. Exclusion of polymeric immunoglobulins and selective immunoglobulin Y transport that recognizes its Fc region in avian ovarian follicles.

    Science.gov (United States)

    Kitaguchi, Kohji; Osada, Kenichi; Horio, Fumihiko; Murai, Atsushi

    2008-02-15

    In avian species, blood immunoglobulin (Ig) Y, the equivalent to mammalian IgG, is selectively incorporated into ovarian follicles, but other classes, IgA and IgM, are much less abundant in the follicles. Several mammalian Igs, including IgG and IgA, are also incorporated into ovarian follicles when administered to birds. To clarify the Ig structure required for incorporation into ovarian follicles, Ig uptakes were determined after the intravenous injection of chicken and human Igs. Three chicken Igs (cIgY, cIgA and cIgM) and two human IgAs (monomeric hIgA and polymeric hIgA) were labeled with digoxigenin, and their uptakes into quail (Coturnix japonica) egg yolks were determined by ELISA and SDS-PAGE. The uptake of cIgY was the highest among the three cIgs (22% of injected cIgY was recovered from egg yolks). Chicken IgA was efficiently incorporated into egg yolk when it formed a monomeric state. Pentameric IgM was untransportable into egg yolk. We also found that the uptake of monomeric hIgA was much more efficient than that of polymeric hIgA. These results suggest that the retention of the monomeric form contributes to the efficient transport of Igs into ovarian follicles. On the other hand, Ig uptakes among monomeric Igs nevertheless differed; for example, a time-course analysis showed that the rate of monomeric cIgY uptake was approximately eight times faster than that of monomeric hIgA. The injection of cIgY fragments Fc, Fab and F(ab')(2) resulted in the largest uptake of Fc fragment, with the same level as that of cIgY. These results suggest the presence of a selective IgY transport system that recognizes its Fc region in avian ovarian follicles.

  19. High-Yield Expression of M2e Peptide of Avian Influenza Virus H5N1 in Transgenic Duckweed Plants.

    Science.gov (United States)

    Firsov, Aleksey; Tarasenko, Irina; Mitiouchkina, Tatiana; Ismailova, Natalya; Shaloiko, Lyubov; Vainstein, Alexander; Dolgov, Sergey

    2015-07-01

    Avian influenza is a major viral disease in poultry. Antigenic variation of this virus hinders vaccine development. However, the extracellular domain of the virus-encoded M2 protein (peptide M2e) is nearly invariant in all influenza A strains, enabling the development of a broad-range vaccine against them. Antigen expression in transgenic plants is becoming a popular alternative to classical expression methods. Here we expressed M2e from avian influenza virus A/chicken/Kurgan/5/2005(H5N1) in nuclear-transformed duckweed plants for further development of avian influenza vaccine. The N-terminal fragment of M2, including M2e, was selected for expression. The M2e DNA sequence fused in-frame to the 5' end of β-glucuronidase was cloned into pBI121 under the control of CaMV 35S promoter. The resulting plasmid was successfully used for duckweed transformation, and western analysis with anti-β-glucuronidase and anti-M2e antibodies confirmed accumulation of the target protein (M130) in 17 independent transgenic lines. Quantitative ELISA of crude protein extracts from these lines showed M130-β-glucuronidase accumulation ranging from 0.09-0.97 mg/g FW (0.12-1.96 % of total soluble protein), equivalent to yields of up to 40 μg M2e/g plant FW. This relatively high yield holds promise for the development of a duckweed-based expression system to produce an edible vaccine against avian influenza.

  20. Governmental Fragmentation in Metropolitan Detroit

    Directory of Open Access Journals (Sweden)

    Davis, Kristal D.

    2012-01-01

    Full Text Available At its population peak in the 1950’s, Detroit, Michigan was inhabited by almost two million residents and served as the car capital of the country. Today, however, the population has dropped by more than fifty percent. With the loss of Detroit residents to surrounding cities and counties, the wedge between Detroit and the suburbs has grown wider. Detroit, once considered the crown jewel of the state of Michigan, is now treated as an immovable stain by its surrounding municipalities. What this means for the metro Detroit area is a high level of governmental fragmentation, preventing economic opportunities for both the city and its suburbs. This is especially unfortunate for the economy of the metro Detroit area because of the current economic crisis in the state of Michigan. With the state’s long tradition of home rule and pride in autonomous, municipal decision-making, municipalities in the metro Detroit area might better realize economic opportunities and the relief they can bring to their own local economies by not only collaborating with the city of Detroit, but with neighboring cities as well.

  1. Free-grazing ducks and highly pathogenic avian influenza, Thailand

    NARCIS (Netherlands)

    Gilbert, Marius; Chaitaweesup, P.; Parakamawongsa, T.; Premashthira, S.; Tiensin, T.; Kalpravidh, W.; Wagner, H.; Slingenbergh, J.

    2006-01-01

    Thailand has recently had 3 epidemic waves of highly pathogenic avian influenza (HPAI); virus was again detected in July 2005. Risk factors need to be identified to better understand disease ecology and assist HPAI surveillance and detection. This study analyzed the spatial distribution of HPAI outb

  2. 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.

  3. Migratory birds reinforce local circulation of avian influenza viruses

    NARCIS (Netherlands)

    Verhagen, J.H.G.; Van Dijk, J.G.B.; Vuong, O.; Lexmond, P.; Klaassen, M.R.J.; Fouchier, R.A.M

    2014-01-01

    Migratory and resident hosts have been hypothesized to fulfil distinct roles in infectious disease dynamics. However, the contribution of resident and migratory hosts to wildlife infectious disease epidemiology, including that of low pathogenic avian influenza virus (LPAIV) in wild birds, has largel

  4. Migratory birds reinforce local circulation of avian influenza viruses

    NARCIS (Netherlands)

    J.H. Verhagen (Josanne); J.G.B. Dijk (Jacintha); O. Vuong (Spronken); T.M. Bestebroer (Theo); P. Lexmond (Pascal); M. Klaassen (Marcel); R.A.M. Fouchier (Ron)

    2014-01-01

    textabstractMigratory and resident hosts have been hypothesized to fulfil distinct roles in infectious disease dynamics. However, the contribution of resident and migratory hosts to wildlife infectious disease epidemiology, including that of low pathogenic avian influenza virus (LPAIV) in wild birds

  5. Investigating Maternal Hormones in Avian Eggs : Measurement, Manipulation, and Interpretation

    NARCIS (Netherlands)

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

    2005-01-01

    The last decade has witnessed a surge in studies on steroid hormones of maternal origin present in avian eggs and affecting offspring development. The value of such studies for the understanding of maternal effects and individual differentiation is endorsed and a series of methodological and concept

  6. Investigating maternal hormones in avian eggs : Measurement, manipulation, and interpretation

    NARCIS (Netherlands)

    Groothuis, TGG; Von Engelhardt, N; Bauchinger, U; Goymann, W; JenniEiermann, S

    2005-01-01

    The last decade has witnessed a surge in studies on steroid hormones of maternal origin present in avian eggs and affecting offspring development. The value of such studies for the understanding of maternal effects and individual differentiation is endorsed and a series of methodological and concept

  7. Scare of Avian Flu Revisits India: A Bumpy Road Ahead

    Directory of Open Access Journals (Sweden)

    Rajnish Kumar Rai

    2008-04-01

    Full Text Available With the threat of an avian flu pandemic once again looming over eastern India, issues regarding patents and affordability and accessibility of drugs have taken center stage. The key priority of India should be to remain prepared to address the public health crisis effectively, by stockpiling the drug tamiflu so that it can be easily distributed and administered to the needy.India had been confronted with a serious threat of avian flu in 2005-06, but past experience shows that, despite having some of the broadest and most comprehensive compulsory patent licensing laws, India's policymaking elite shied away from fully exploiting these legal 'flexibilities.' Fortunately, the danger of avian flu did not turn into a substantial public health crisis that year. Under this backdrop, this paper explores various ‘flexibilities’ available in the Indian patent law and suggests short term and long term strategies to effectively tackle the impending danger of an avian flu pandemic, and similar public health crises in future. This paper will discuss potential areas of conflict between the indigenous generic drug firms and the multi-national companies with respect to TRIPS compliance in the event that these flexibilities are exploited. This paper also highlights the administrative constraints and the economic viability of the compulsory licensing system. Finally, this paper shows how political will is often more critical than having well documented provisions in statute books to respond to such situations effectively.

  8. Avian Influenza A (H7N9) Virus

    Science.gov (United States)

    ... this? Submit Button Past Newsletters Avian Influenza A (H7N9) Virus Language: English Español Recommend on Facebook ... Fourth Epidemic — China, September 2015–August 2016." H7N9 Outbreak Characterization H7N9 infections in people and poultry ...

  9. Rapidly expanding range of highly pathogenic avian influenza viruses

    Science.gov (United States)

    The recent introduction of highly pathogenic avian influenza virus (HPAIV) H5N8 into Europe and North America poses significant risks to poultry industries and wildlife populations and warrants continued and heightened vigilance. First discovered in South Korean poultry and wild birds in early 2014...

  10. Developmental imaging: the avian embryo hatches to the challenge.

    Science.gov (United States)

    Kulesa, Paul M; McKinney, Mary C; McLennan, Rebecca

    2013-06-01

    The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair.

  11. Avian Hepatitis E Virus Infection in Organic Layers.

    Science.gov (United States)

    Crespo, Rocio; Opriessnig, Tanja; Uzal, Francisco; Gerber, Priscilla F

    2015-09-01

    Between 2012 and 2014, 141 chickens from 10 organic layer flocks with a history of severe drop in egg production (up to 40%) and slight increased mortality (up to 1% per week) were submitted to the Avian Health and Food Safety Laboratory (Puyallup, WA). At necropsy, the most common finding was pinpoint white foci on the liver and regressed ova without any other remarkable lesions. Histologically, there was multifocal mild-to-severe acute necrotizing hepatitis present. No significant bacteria were recovered from liver samples, and tests for mycotoxins were negative. Twenty-six serum samples from four affected flocks tested were positive for avian hepatitis E virus (HEV) immunoglobulin Y antibodies. Avian HEV RNA was detected in 10 livers of chickens from two different affected flocks. The avian HEV was characterized by sequencing and determined to belong to genotype 2. The diagnosis of a clinical manifest HEV was based solely on the demonstration of specific viral RNA and the absence of other causative agents in samples from flocks, as the clinical sings and pathologic lesions were atypical.

  12. Low frequency of paleoviral infiltration across the avian phylogeny

    DEFF Research Database (Denmark)

    Cui, Jie; Zhao, Wei; Huang, Zhiyong

    2014-01-01

    of endogenous viral element evolution.Results: Through a systematic screening of the genomes of 48 species sampled across the avian phylogeny we reveal that birds harbor a limited number of endogenous viral elements compared to mammals, with only five viral families observed: Retroviridae, Hepadnaviridae...

  13. First characterization of avian influenza viruses from Greenland 2014

    DEFF Research Database (Denmark)

    Hartby, Christina Marie; Krog, Jesper Schak; Ravn Merkel, Flemming;

    2016-01-01

    In late February 2014, unusually high numbers of wild birds, thick-billed murre (Uria lomvia), were found dead at the coast of South Greenland. To investigate the cause of death, 45 birds were submitted for laboratory examinations in Denmark. Avian influenza viruses (AIVs) with subtypes H11N2...

  14. Cell culture based production of avian influenza vaccines

    NARCIS (Netherlands)

    Wielink, van R.

    2012-01-01

    Vaccination of poultry can be used as a tool to control outbreaks of avian influenza, including that of highly pathogenic H5 and H7 strains. Influenza vaccines are traditionally produced in embryonated chicken eggs. Continuous cell lines have been suggested as an alternative substrate to produce inf

  15. Pathogenicity of highly pathogenic avian influenza virus in mammals

    NARCIS (Netherlands)

    E. de Wit (Emmie); Y. Kawaoka (Yoshihiro); M.D. de Jong (Menno); R.A.M. Fouchier (Ron)

    2008-01-01

    textabstractIn recent years, there has been an increase in outbreaks of highly pathogenic avian influenza (HPAI) in poultry. Occasionally, these outbreaks have resulted in transmission of influenza viruses to humans and other mammals, with symptoms ranging from conjunctivitis to pneumonia and death.

  16. Avian dendritic cells: Phenotype and ontogeny in lymphoid organs.

    Science.gov (United States)

    Nagy, Nándor; Bódi, Ildikó; Oláh, Imre

    2016-05-01

    Dendritic cells (DC) are critically important accessory cells in the innate and adaptive immune systems. Avian DCs were originally identified in primary and secondary lymphoid organs by their typical morphology, displaying long cell processes with cytoplasmic granules. Several subtypes are known. Bursal secretory dendritic cells (BSDC) are elongated cells which express vimentin intermediate filaments, MHC II molecules, macrophage colony-stimulating factor 1 receptor (CSF1R), and produce 74.3+ secretory granules. Avian follicular dendritic cells (FDC) highly resemble BSDC, express the CD83, 74.3 and CSF1R molecules, and present antigen in germinal centers. Thymic dendritic cells (TDC), which express 74.3 and CD83, are concentrated in thymic medulla while interdigitating DC are found in T cell-rich areas of secondary lymphoid organs. Avian Langerhans cells are a specialized 74.3-/MHC II+ cell population found in stratified squamous epithelium and are capable of differentiating into 74.3+ migratory DCs. During organogenesis hematopoietic precursors of DC colonize the developing lymphoid organ primordia prior to immigration of lymphoid precursor cells. This review summarizes our current understanding of the ontogeny, cytoarchitecture, and immunophenotype of avian DC, and offers an antibody panel for the in vitro and in vivo identification of these heterogeneous cell types.

  17. Rapidly expanding range of highly pathogenic avian influenza viruses

    Science.gov (United States)

    Hall, Jeffrey S.; Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.

  18. Avian Metapneumovirus Molecular Biology and Development of Genetically Engineered Vaccines

    Science.gov (United States)

    Avian metapneumovirus (aMPV) is an economically important pathogen of turkeys with a worldwide distribution. aMPV is a member of the genus Metapneumovirus within the subfamily Pneumovirinae of the family Paramyxoviridae. The genome of aMPV is a non-segmented, single-stranded, negative-sense RNA of 1...

  19. Conjunctiva-associated lymphoid tissue in avian mucosal immunity

    NARCIS (Netherlands)

    Ginkel, van F.W.; Gulley, S.L.; Lammers, A.; Hoerr, F.J.; Gurjar, R.; Toro, H.

    2012-01-01

    Conjunctiva-associated lymphoid tissue’s (CALT) role in generating avian mucosal adaptive immunity was measured by analyzing cellular composition, expression of the polymeric immunoglobulin receptor (pIgR), and production of cytokines and antibodies in chickens ocular exposed to a replication-defici

  20. Duck Hunters’ Perceptions of Risk for Avian Influenza, Georgia, USA

    OpenAIRE

    Dishman, Hope; Stallknecht, David; Cole, Dana

    2010-01-01

    To determine duck hunters’ risk for highly pathogenic avian influenza, we surveyed duck hunters in Georgia, USA, during 2007–2008, about their knowledge, attitudes, and practices. We found they engage in several practices that could expose them to the virus. Exposures and awareness were highest for those who had hunted >10 years.

  1. Duck hunters' perceptions of risk for avian influenza, Georgia, USA.

    Science.gov (United States)

    Dishman, Hope; Stallknecht, David; Cole, Dana

    2010-08-01

    To determine duck hunters'risk for highly pathogenic avian influenza, we surveyed duck hunters in Georgia, USA, during 2007-2008, about their knowledge, attitudes, and practices. We found they engage in several practices that could expose them to the virus. Exposures and awareness were highest for those who had hunted >10 years.

  2. Biochemical characterization of the small hydrophobic protein of avian metapneumovirus

    Science.gov (United States)

    Avian metapneumovirus (aMPV) is a paramyxovirus that has three membrane-associate proteins: glycoprotein (G), fusion (F), and small hydrophobic (SH) proteins. Among them, the SH protein is a small type II integral membrane protein that is incorporated into virions and is only present in certain para...

  3. Avian influenza and pandemic influenza preparedness in Hong Kong.

    Science.gov (United States)

    Lam, Ping Yan

    2008-06-01

    Avian influenza A H5N1 continues to be a major threat to global public health as it is a likely candidate for the next influenza pandemic. To protect public health and avert potential disruption to the economy, the Hong Kong Special Administrative Region Government has committed substantial effort in preparedness for avian and pandemic influenza. Public health infrastructures for emerging infectious diseases have been developed to enhance command, control and coordination of emergency response. Strategies against avian and pandemic influenza are formulated to reduce opportunities for human infection, detect pandemic influenza timely, and enhance emergency preparedness and response capacity. Key components of the pandemic response include strengthening disease surveillance systems, updating legislation on infectious disease prevention and control, enhancing traveller health measures, building surge capacity, maintaining adequate pharmaceutical stockpiles, and ensuring business continuity during crisis. Challenges from avian and pandemic influenza are not to be underestimated. Implementing quarantine and social distancing measures to contain or mitigate the spread of pandemic influenza is problematic in a highly urbanised city like Hong Kong as they involved complex operational and ethical issues. Sustaining effective risk communication campaigns during interpandemic times is another challenge. Being a member of the global village, Hong Kong is committed to contributing its share of efforts and collaborating with health authorities internationally in combating our common public health enemy.

  4. Indirect transmission of highly pathogenic avian influenza in chickens

    NARCIS (Netherlands)

    Spekreijse, D.

    2013-01-01

    Highly Pathogenic Avian Influenza (HPAI), also known bird flu, is a serious infectious disease of chickens causing high mortality in flocks and economic damage for farmers. The control strategy to control an outbreak of HPAI in the Netherlands will include culling of infected flocks and depopulation

  5. Vaccines and vaccination for avian influenza in poultry

    Science.gov (United States)

    Avian influenza (AI) vaccines have been developed and used to protect poultry and other birds in various countries of the world. Protection is principally mediated by an immune response to the subtype-specific hemagglutinin (HA) protein. AI vaccines prevent clinical signs of disease, death, egg pr...

  6. Fish on avian lampbrush chromosomes produces higher resolution gene mapping

    NARCIS (Netherlands)

    Galkina, S.A.; Deryusheva, S.; Fillon, V.; Vignal, A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Rodionov, A.V.; Gaginskaya, E.

    2006-01-01

    Giant lampbrush chromosomes, which are characteristic of the diplotene stage of prophase I during avian oogenesis, represent a very promising system for precise physical gene mapping. We applied 35 chicken BAC and 4 PAC clones to both mitotic metaphase chromosomes and meiotic lampbrush chromosomes o

  7. 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....

  8. Application of in-situ hybridization for the detection and identification of avian malaria parasites in paraffin wax-embedded tissues from captive penguins.

    Science.gov (United States)

    Dinhopl, Nora; Mostegl, Meike M; Richter, Barbara; Nedorost, Nora; Maderner, Anton; Fragner, Karin; Weissenböck, Herbert

    2011-06-01

    In captive penguins, avian malaria due to Plasmodium parasites is a well-recognized disease problem as these protozoa may cause severe losses among valuable collections of zoo birds. In blood films from naturally infected birds, identification and differentiation of malaria parasites based on morphological criteria are difficult because parasitaemia is frequently light and blood stages, which are necessary for identification of parasites, are often absent. Post-mortem diagnosis by histological examination of tissue samples is sometimes inconclusive due to the difficulties in differentiating protozoal tissue stages from fragmented nuclei in necrotic tissue. The diagnosis of avian malaria would be facilitated by a technique with the ability to specifically identify developmental stages of Plasmodium in tissue samples. Thus, a chromogenic in-situ hybridization (ISH) procedure with a digoxigenin-labelled probe, targeting a fragment of the 18S rRNA, was developed for the detection of Plasmodium parasites in paraffin wax-embedded tissues. This method was validated in comparison with traditional techniques (histology, polymerase chain reaction), on various tissues from 48 captive penguins that died at the zoological garden Schönbrunn, Vienna, Austria. Meronts of Plasmodium gave clear signals and were easily identified using ISH. Potential cross-reactivity of the probe was ruled out by the negative outcome of the ISH against a number of protozoa and fungi. Thus, ISH proved to be a powerful, specific and sensitive tool for unambiguous detection of Plasmodium parasites in paraffin wax-embedded tissue samples.

  9. Pollen and gene flow in fragmented habitats

    NARCIS (Netherlands)

    Kwak, Manja M.; Velterop, Odilia; van Andel, Jelte

    1998-01-01

    . Habitat fragmentation affects both plants and pollinators. Habitat fragmentation leads to changes in species richness, population number and size, density, and shape, thus to changes in the spatial arrangement of flowers. These changes influence the amount of food for flower-visiting insects and t

  10. Baculovirus display of functional antibody Fab fragments.

    Science.gov (United States)

    Takada, Shinya; Ogawa, Takafumi; Matsui, Kazusa; Suzuki, Tasuku; Katsuda, Tomohisa; Yamaji, Hideki

    2015-08-01

    The generation of a recombinant baculovirus that displays antibody Fab fragments on the surface was investigated. A recombinant baculovirus was engineered so that the heavy chain (Hc; Fd fragment) of a mouse Fab fragment was expressed as a fusion to the N-terminus of baculovirus gp64, while the light chain of the Fab fragment was simultaneously expressed as a secretory protein. Following infection of Sf9 insect cells with the recombinant baculovirus, the culture supernatant was analyzed by enzyme-linked immunosorbent assay using antigen-coated microplates and either an anti-mouse IgG or an anti-gp64 antibody. A relatively strong signal was obtained in each case, showing antigen-binding activity in the culture supernatant. In western blot analysis of the culture supernatant using the anti-gp64 antibody, specific protein bands were detected at an electrophoretic mobility that coincided with the molecular weight of the Hc-gp64 fusion protein as well as that of gp64. Flow cytometry using a fluorescein isothiocyanate-conjugated antibody specific to mouse IgG successfully detected the Fab fragments on the surface of the Sf9 cells. These results suggest that immunologically functional antibody Fab fragments can be displayed on the surface of baculovirus particles, and that a fluorescence-activated cell sorter with a fluorescence-labeled antigen can isolate baculoviruses displaying specific Fab fragments. This successful baculovirus display of antibody Fab fragments may offer a novel approach for the efficient selection of specific antibodies.

  11. The Family Circle: A Study in Fragmentation

    Science.gov (United States)

    Bronfenbrenner, Urie

    1976-01-01

    Presents data describing the fragmentation of the family, suggests causes for the fragmentation, and offers suggestions for reversing the trend. The suggestions focus on day care, part-time employment practices, enhancing the position of women, and work and responsibility. (IRT)

  12. Modelling distribution functions and fragmentation functions

    CERN Document Server

    Rodrigues, J; Mulders, P J

    1995-01-01

    We present examples for the calculation of the distribution and fragmentation functions using the representation in terms of non-local matrix elements of quark field operators. As specific examples, we use a simple spectator model to estimate the leading twist quark distribution functions and the fragmentation functions for a quark into a nucleon or a pion.

  13. First principles approach to ionicity of fragments

    Science.gov (United States)

    Pilania, Ghanshyam; Liu, Xiang-Yang; Valone, Steven M.

    2015-02-01

    We develop a first principles approach towards the ionicity of fragments. In contrast to the bond ionicity, the fragment ionicity refers to an electronic property of the constituents of a larger system, which may vary from a single atom to a functional group or a unit cell to a crystal. The fragment ionicity is quantitatively defined in terms of the coefficients of contributing charge states in a superposition of valence configurations of the system. Utilizing the constrained density functional theory-based computations, a practical method to compute the fragment ionicity from valence electron charge densities, suitably decomposed according to the Fragment Hamiltonian (FH) model prescription for those electron densities, is presented for the first time. The adopted approach is illustrated using BeO, MgO and CaO diatomic molecules as simple examples. The results are compared and discussed with respect to the bond ionicity scales of Phillips and Pauling.

  14. The politics of municipal fragmentation in Ghana

    Directory of Open Access Journals (Sweden)

    Abdulai Kuyini Mohammed

    2015-06-01

    Full Text Available The scholarly debate over the rival merits of local government consolidation and fragmentation is an old but enduring one. However, in this debate very little attention has been focused on the political dimension of council amalgamation and fragmentation – yet political considerations play a central role in both the formulation and outcomes of de-concentration policy. The purpose of this article is to fill a gap in the literature by examining local government fragmentation in Ghana from 1988 to 2014. The article does this by identifying the key players and analysing their interests and gains, as well as the tensions arising from the fragmentation exercise. The implications from the Ghanaian case for more general theories of fragmentation are drawn out.

  15. CLP-based protein fragment assembly

    CERN Document Server

    Palu', Alessandro Dal; Fogolari, Federico; Pontelli, Enrico; 10.1017/S1471068410000372

    2010-01-01

    The paper investigates a novel approach, based on Constraint Logic Programming (CLP), to predict the 3D conformation of a protein via fragments assembly. The fragments are extracted by a preprocessor-also developed for this work- from a database of known protein structures that clusters and classifies the fragments according to similarity and frequency. The problem of assembling fragments into a complete conformation is mapped to a constraint solving problem and solved using CLP. The constraint-based model uses a medium discretization degree Ca-side chain centroid protein model that offers efficiency and a good approximation for space filling. The approach adapts existing energy models to the protein representation used and applies a large neighboring search strategy. The results shows the feasibility and efficiency of the method. The declarative nature of the solution allows to include future extensions, e.g., different size fragments for better accuracy.

  16. Inhibiting avian influenza virus shedding using a novel RNAi antiviral vector technology: proof of concept in an avian cell model.

    Science.gov (United States)

    Linke, Lyndsey M; Wilusz, Jeffrey; Pabilonia, Kristy L; Fruehauf, Johannes; Magnuson, Roberta; Olea-Popelka, Francisco; Triantis, Joni; Landolt, Gabriele; Salman, Mo

    2016-03-01

    Influenza A viruses pose significant health and economic threats to humans and animals. Outbreaks of avian influenza virus (AIV) are a liability to the poultry industry and increase the risk for transmission to humans. There are limitations to using the AIV vaccine in poultry, creating barriers to controlling outbreaks and a need for alternative effective control measures. Application of RNA interference (RNAi) techniques hold potential; however, the delivery of RNAi-mediating agents is a well-known obstacle to harnessing its clinical application. We introduce a novel antiviral approach using bacterial vectors that target avian mucosal epithelial cells and deliver (small interfering RNA) siRNAs against two AIV genes, nucleoprotein (NP) and polymerase acidic protein (PA). Using a red fluorescent reporter, we first demonstrated vector delivery and intracellular expression in avian epithelial cells. Subsequently, we demonstrated significant reductions in AIV shedding when applying these anti-AIV vectors prophylactically. These antiviral vectors provided up to a 10,000-fold reduction in viral titers shed, demonstrating in vitro proof-of-concept for using these novel anti-AIV vectors to inhibit AIV shedding. Our results indicate this siRNA vector technology could represent a scalable and clinically applicable antiviral technology for avian and human influenza and a prototype for RNAi-based vectors against other viruses.

  17. The avian influenza H9N2 at avian-human interface: A possible risk for the future pandemics

    Directory of Open Access Journals (Sweden)

    Shaghayegh RahimiRad

    2016-01-01

    Full Text Available The avian influenza subtype H9N2 is considered a low pathogenic virus which is endemic in domestic poultry of a majority of Asian countries. Many reports of seropositivity in occupationally poultry-exposed workers and a number of confirmed human infections with an H9N2 subtype of avian influenza have been documented up to now. Recently, the human infections with both H7N9 and H10N8 viruses highlighted that H9N2 has a great potential for taking a part in the emergence of new human-infecting viruses. This review aimed at discussing the great potential of H9N2 virus which is circulating at avian-human interface, for cross-species transmission, contribution in the production of new reassortants and emergence of new pandemic subtypes. An intensified surveillance is needed for controlling the future risks which would be created by H9N2 circulation at avian-human interfaces.

  18. Avian communities in baylands and artificial salt evaporation ponds of the San Francisco Bay estuary

    Science.gov (United States)

    Takekawa, J.Y.; Lu, C.T.; Pratt, R.T.

    2001-01-01

    San Francisco Bay wetlands, seasonal and tidal marshes between the historic low and high tide lines, are now highly fragmented because of development during the past 150 years. Artificial salt pond systems in the Bay are hypersaline and typically support simple assemblages of algae and invertebrates. In order to establish the value of salt ponds for migratory waterbirds, we used datasets to conduct a meta-analysis of avian communities in the baylands and salt ponds of San Pablo Bay. Fifty-three species of waterbirds in the salt ponds represented six foraging guilds: surface feeders, shallow probers, deep probers, dabblers, diving benthivores and piscivores. The total number of species and the Shannon-Weiner diversity index was higher in baylands than in salt ponds during all four seasons. However, overall bird density (number/ha) was higher in salt ponds compared with baylands in the winter and spring, primarily because of large concentrations of benthivores. Cessation of salt production in 1993 and subsequent reduction in water depth resulted in a decline of some diving duck populations that used the salt ponds.

  19. Exact Solutions of Fragmentation Equations with General Fragmentation Rates and Separable Particles Distribution Kernels

    Directory of Open Access Journals (Sweden)

    S. C. Oukouomi Noutchie

    2014-01-01

    Full Text Available We make use of Laplace transform techniques and the method of characteristics to solve fragmentation equations explicitly. Our result is a breakthrough in the analysis of pure fragmentation equations as this is the first instance where an exact solution is provided for the fragmentation evolution equation with general fragmentation rates. This paper is the key for resolving most of the open problems in fragmentation theory including “shattering” and the sudden appearance of infinitely many particles in some systems with initial finite particles number.

  20. Genetic data from avian influenza and avian paramyxoviruses generated by the European network of excellence (EPIZONE) between 2006 and 2011—Review and recommendations for surveillance

    DEFF Research Database (Denmark)

    Dundon, William G.; Heidari, Alireza; Fusaro, Alice

    2012-01-01

    Since 2006, the members of the molecular epidemiological working group of the European “EPIZONE” network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation...

  1. Improved chemical shift based fragment selection for CS-Rosetta using Rosetta3 fragment picker

    Energy Technology Data Exchange (ETDEWEB)

    Vernon, Robert [Hospital for Sick Children, Program in Molecular Structure and Function (Canada); Shen, Yang [National Institutes of Health, Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases (United States); Baker, David [University of Washington, Department of Biochemistry (United States); Lange, Oliver F., E-mail: oliver.lange@tum.de [Technische Universitaet Muenchen, Department Chemie, Biomolecular NMR and Munich Center for Integrated Protein Science (Germany)

    2013-10-15

    A new fragment picker has been developed for CS-Rosetta that combines beneficial features of the original fragment picker, MFR, used with CS-Rosetta, and the fragment picker, NNMake, that was used for purely sequence based fragment selection in the context of ROSETTA de-novo structure prediction. Additionally, the new fragment picker has reduced sensitivity to outliers and other difficult to match data points rendering the protocol more robust and less likely to introduce bias towards wrong conformations in cases where data is bad, missing or inconclusive. The fragment picker protocol gives significant improvements on 6 of 23 CS-Rosetta targets. An independent benchmark on 39 protein targets, whose NMR data sets were published only after protocol optimization had been finished, also show significantly improved performance for the new fragment picker (van der Schot et al. in J Biomol NMR, 2013)

  2. Virtual fragment screening: an exploration of various docking and scoring protocols for fragments using Glide

    Science.gov (United States)

    Kawatkar, Sameer; Wang, Hongming; Czerminski, Ryszard; Joseph-McCarthy, Diane

    2009-08-01

    Fragment-based drug discovery approaches allow for a greater coverage of chemical space and generally produce high efficiency ligands. As such, virtual and experimental fragment screening are increasingly being coupled in an effort to identify new leads for specific therapeutic targets. Fragment docking is employed to create target-focussed subset of compounds for testing along side generic fragment libraries. The utility of the program Glide with various scoring schemes for fragment docking is discussed. Fragment docking results for two test cases, prostaglandin D2 synthase and DNA ligase, are presented and compared to experimental screening data. Self-docking, cross-docking, and enrichment studies are performed. For the enrichment runs, experimental data exists indicating that the docking decoys in fact do not inhibit the corresponding enzyme being examined. Results indicate that even for difficult test cases fragment docking can yield enrichments significantly better than random.

  3. Decomposition and fragmentation principles in computational chemistry

    Science.gov (United States)

    Mezey, Paul G.

    2015-12-01

    A common approach to the mathematical modeling of various objects and processes is the subdivision of the problem into smaller, (and, as hoped), more easily understandable entities. By modeling these smaller entities, which are often fragments of the whole, and eventually re-combining these smaller fragment models into a model of the whole, one may expect that a reasonably reliable modeling approach for the complete problem may be obtained. One crucial aspect of such an approach is the level of complexity of the interrelations between the fragments. If the interrelations are weak and relatively simple, than the fragmentation approach may succeed and provide satisfactory results. However, as often happens, the interrelations are complex and not well understood, and then the fragmentation approach may face difficulties and even fail. One field where the interrelations between potential fragments is strong, yet the fragment-based approach has proven to be successful, is the modelling of both small and large molecules, providing valuable lessons for some fields not directly linked to chemistry.

  4. Changes in avian disease and mosquito vector prevalence; A 15-year perceptive and assessment of future risk: Hakalau National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Mosquito-borne avian disease, avian malaria and avian pox, is a major limiting factor for Hawaiian forest birds. While native bird communities at Hakalau Forest NWR...

  5. New information on photon fragmentation functions

    CERN Document Server

    Klasen, M

    2014-01-01

    Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of the prompt photons produced simultaneously in hard collisions of quarks and gluons, mostly through their fragmentation. In this Letter, we demonstrate that PHENIX data on photons produced in proton-proton collisions with low transverse momenta allow to extract new information on this fragmentation process. In particular, these data favor one parameterization (BFG II) over the two other frequently used photon fragmentation functions (BFG I and GRV NLO).

  6. HETC-3STEP included fragmentation process

    Energy Technology Data Exchange (ETDEWEB)

    Shigyo, Nobuhiro; Iga, Kiminori; Ishibashi, Kenji [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering

    1997-03-01

    High Energy Transport Code (HETC) based on the cascade-evaporation model is modified to calculate the fragmentation cross section. For the cascade process, nucleon-nucleon cross sections are used for collision computation; effective in-medium-corrected cross sections are adopted instead of the original free-nucleon collision. The exciton model is adopted for improvement of backward nucleon-emission cross section for low-energy nucleon-incident events. The fragmentation reaction is incorporated into the original HETC as a subroutine set by the use of the systematics of the reaction. The modified HETC (HETC-3STEP/FRG) reproduces experimental fragment yields to a reasonable degree. (author)

  7. Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, Wallace P.; Johnson, Gregory D.; Strickland, Dale M.; Young, Jr., David P.; Sernka, Karyn J.; Good, Rhett E.

    2001-08-01

    It has been estimated that from 100 million to well over 1 billion birds are killed annually in the United States due to collisions with human-made structures, including vehicles, buildings and windows, powerlines, communication towers, and wind turbines. Although wind energy is generally considered environmentally friendly (because it generates electricity without emitting air pollutants or greenhouse gases), the potential for avian fatalities has delayed and even significantly contributed to blocking the development of some windplants in the U.S. Given the importance of developing a viable renewable source of energy, the objective of this paper is to put the issue of avian mortality associated with windpower into perspective with other sources of avian collision mortality across the U.S. The purpose of this paper is to provide a detailed summary of the mortality data collected at windplants and put avian collision mortality associated with windpower development into perspective with other significant sources of avian collision mortality across the United States. We provide a summary of data collected at many of the U.S. windplants and provide annual bird fatality estimates and projections for all wind turbines in the U.S. For comparison, we also review studies of avian collision mortality from other major human-made structures and report annual bird fatality estimates for these sources. Other sources also significantly contribute to overall avian mortality. For example, the National Audubon Society estimates avian mortality due to house cats at 100 million birds per year. Pesticide use, oil spills, disease, etc., are other significant sources of unintended avian mortality. Due to funding constraints, the scope of this paper is limited to examining only avian mortality resulting from collisions with human-made obstacles.

  8. Detection of evolutionarily distinct avian influenza a viruses in antarctica.

    Science.gov (United States)

    Hurt, Aeron C; Vijaykrishna, Dhanasekaran; Butler, Jeffrey; Baas, Chantal; Maurer-Stroh, Sebastian; Silva-de-la-Fuente, M Carolina; Medina-Vogel, Gonzalo; Olsen, Bjorn; Kelso, Anne; Barr, Ian G; González-Acuña, Daniel

    2014-05-06

    ABSTRACT Distinct lineages of avian influenza viruses (AIVs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. Virtually nothing is known from the Antarctic. Using virus culture, molecular analysis, full genome sequencing, and serology of samples from Adélie penguins in Antarctica, we confirmed infection by H11N2 subtype AIVs. Their genetic segments were distinct from all known contemporary influenza viruses, including South American AIVs, suggesting spatial separation from other lineages. Only in the matrix and polymerase acidic gene phylogenies did the Antarctic sequences form a sister relationship to South American AIVs, whereas distant phylogenetic relationships were evident in all other gene segments. Interestingly, their neuraminidase genes formed a distant relationship to all avian and human influenza lineages, and the polymerase basic 1 and polymerase acidic formed a sister relationship to the equine H3N8 influenza virus lineage that emerged during 1963 and whose avian origins were previously unknown. We also estimated that each gene segment had diverged for 49 to 80 years from its most closely related sequences, highlighting a significant gap in our AIV knowledge in the region. We also show that the receptor binding properties of the H11N2 viruses are predominantly avian and that they were unable to replicate efficiently in experimentally inoculated ferrets, suggesting their continuous evolution in avian hosts. These findings add substantially to our understanding of both the ecology and the intra- and intercontinental movement of Antarctic AIVs and highlight the potential risk of an incursion of highly pathogenic AIVs into this fragile environment. IMPORTANCE Avian influenza viruses (AIVs) are typically maintained and spread by migratory birds, resulting in the existence of distinctly different viruses around the world. However, AIVs have not previously been detected in Antarctica. In this study, we

  9. Construction of an infectious cDNA clone of avian hepatitis E virus (avian HEV) recovered from a clinically healthy chicken in the United States and characterization of its pathogenicity in specific-pathogen-free chickens.

    Science.gov (United States)

    Kwon, Hyuk Moo; LeRoith, Tanya; Pudupakam, R S; Pierson, F William; Huang, Yao-Wei; Dryman, Barbara A; Meng, Xiang-Jin

    2011-01-27

    A genetically distinct strain of avian hepatitis E virus (avian HEV-VA strain) was isolated from a healthy chicken in Virginia, and thus it is important to characterize and compare its pathogenicity with the prototype strain (avian HEV-prototype) isolated from a diseased chicken. Here we first constructed an infectious clone of the avian HEV-VA strain. Capped RNA transcripts from the avian HEV-VA clone were replication-competent after transfection of LMH chicken liver cells. Chickens inoculated intrahepatically with RNA transcripts of avian HEV-VA clone developed active infection as evidenced by fecal virus shedding, viremia, and seroconversion. To characterize the pathogenicity, RNA transcripts of both avian HEV-VA and avian HEV-prototype clones were intrahepatically inoculated into the livers of chickens. Avian HEV RNA was detected in feces, serum and bile samples from 10/10 avian HEV-VA-inoculated and 9/9 avian HEV-prototype-inoculated chickens although seroconversion occurred only in some chickens during the experimental period. The histopathological lesion scores were lower for avian HEV-VA group than avian HEV-prototype group in the liver at 3 and 5 weeks post-inoculation (wpi) and in the spleen at 3 wpi, although the differences were not statistically significant. The liver/body weight ratio, indicative of liver enlargement, of both avian HEV-VA and avian HEV-prototype groups were significantly higher than that of the control group at 5 wpi. Overall, the avian HEV-VA strain still induces histological liver lesions even though it was isolated from a healthy chicken. The results also showed that intrahepatic inoculation of chickens with RNA transcripts of avian HEV infectious clone may serve as an alternative for live virus in animal pathogenicity studies.

  10. Microsatellite typing of Aspergillus flavus from clinical and environmental avian isolates

    OpenAIRE

    2013-01-01

    Aspergillosis is one of the most common causes of death in captive birds. Aspergillus fumigatus accounts for approximately 95 % of aspergillosis cases and Aspergillus flavus is the second most frequent organism associated with avian infections. In the present study, the fungi were grown from avian clinical samples (post-mortem lung material) and environmental samples (eggs, food and litter). Microsatellite markers were used to type seven clinical avian isolates and 22 environmental isolates o...

  11. Avian Colibacillosis and Salmonellosis: A Closer Look at Epidemiology, Pathogenesis, Diagnosis, Control and Public Health Concerns

    OpenAIRE

    2010-01-01

    Avian colibacillosis and salmonellosis are considered to be the major bacterial diseases in the poultry industry world-wide. Colibacillosis and salmonellosis are the most common avian diseases that are communicable to humans. This article provides the vital information on the epidemiology, pathogenesis, diagnosis, control and public health concerns of avian colibacillosis and salmonellosis. A better understanding of the information addressed in this review article will assist the poultry rese...

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

    OpenAIRE

    Kominis, I. K.

    2008-01-01

    The intricate biochemical processes underlying avian magnetoreception, the sensory ability of migratory birds to navigate using earths magnetic field, have been narrowed down to spin-dependent recombination of radical-ion pairs to be found in avian species retinal proteins. The avian magnetic field detection is governed by the interplay between magnetic interactions of the radicals unpaired electrons and the radicals recombination dynamics. Critical to this mechanism is the long lifetime of t...

  13. Energy efficiency of consecutive fragmentation processes

    CERN Document Server

    Fontbona, Joaquin; Martinez, Servet

    2010-01-01

    We present a ?rst study on the energy required to reduce a unit mass fragment by consecutively using several devices, as it happens in the mining industry. Two devices are considered, which we represent as different stochastic fragmentation processes. Following the self-similar energy model introduced by Bertoin and Martinez, we compute the average energy required to attain a size x with this two-device procedure. We then asymptotically compare, as x goes to 0 or 1, its energy requirement with that of individual fragmentation processes. In particular, we show that for certain range of parameters of the fragmentation processes and of their energy cost-functions, the consecutive use of two devices can be asymptotically more efficient than using each of them separately, or conversely.

  14. The NJL Model for Quark Fragmentation Functions

    Energy Technology Data Exchange (ETDEWEB)

    T. Ito, W. Bentz, I. Cloet, A W Thomas, K. Yazaki

    2009-10-01

    A description of fragmentation functions which satisfy the momentum and isospin sum rules is presented in an effective quark theory. Concentrating on the pion fragmentation function, we first explain the reason why the elementary (lowest order) fragmentation process q → qπ is completely inadequate to describe the empirical data, although the “crossed” process π → qq describes the quark distribution functions in the pion reasonably well. Then, taking into account cascade-like processes in a modified jet-model approach, we show that the momentum and isospin sum rules can be satisfied naturally without introducing any ad-hoc parameters. We present numerical results for the Nambu-Jona-Lasinio model in the invariant mass regularization scheme, and compare the results with the empirical parametrizations. We argue that this NJL-jet model provides a very useful framework to calculate the fragmentation functions in an effective chiral quark theory.

  15. An improved algorithm for MFR fragment assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kontaxis, Georg, E-mail: georg.kontaxis@univie.ac.at [University of Vienna, Max F. Perutz Laboratories, Department of Structural and Computational Biology, Centre for Molecular Biology (Austria)

    2012-06-15

    A method for generating protein backbone models from backbone only NMR data is presented, which is based on molecular fragment replacement (MFR). In a first step, the PDB database is mined for homologous peptide fragments using experimental backbone-only data i.e. backbone chemical shifts (CS) and residual dipolar couplings (RDC). Second, this fragment library is refined against the experimental restraints. Finally, the fragments are assembled into a protein backbone fold using a rigid body docking algorithm using the RDCs as restraints. For improved performance, backbone nuclear Overhauser effects (NOEs) may be included at that stage. Compared to previous implementations of MFR-derived structure determination protocols this model-building algorithm offers improved stability and reliability. Furthermore, relative to CS-ROSETTA based methods, it provides faster performance and straightforward implementation with the option to easily include further types of restraints and additional energy terms.

  16. FOREST FRAGMENTATION AS AN ECONOMIC INDICATOR

    Science.gov (United States)

    Despite concern over the ecological consequences of conversion of land from natural cover to anthropogenic uses, there are few studies that show a quantitative relationship between fragmentation and economic factors. For the southside economic region of Virginia, we generated a ...

  17. Gravitational fragmentation of the Carina Flare supershell

    Science.gov (United States)

    Wünsch, Richard

    2015-03-01

    We study the gravitational fragmentation of a thick shell comparing the analytical theory to 3D hydrodynamic simulations and to observations of the Carina Flare supershell. We use both grid-based (AMR) and particle-based (SPH) codes to follow the idealised model of the fragmenting shell and found an excellent agreement between the two codes. Growth rates of fragments at different wavelength are well described by the pressure assisted gravitational instability (PAGI) - a new theory of the thick shell fragmentation. Using the APEX telescope we observe a part of the surface of the Carina Flare supershell (GSH287+04-17) in the 13CO(2-1) line. We apply a new clump-finding algorithm DENDROFIND to identify 50 clumps. We determine the clump mass function and we construct the minimum spanning tree connecting clumps positions to estimate the typical distance among clumps. We conclude that the observed masses and distances correspond well to the prediction of PAGI.

  18. Anthropogenic Fragmentation in the western United States

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — We evaluated the fragmentation of the western United States by anthropogenic features. The addition of roads, railroads, and power lines to wildlands, and the...

  19. Oscillating Filaments: I - Oscillation and Geometrical Fragmentation

    CERN Document Server

    Gritschneder, Matthias; Burkert, Andreas

    2016-01-01

    We study the stability of filaments in equilibrium between gravity and internal as well as external pressure using the grid based AMR-code RAMSES. A homogeneous, straight cylinder below a critical line mass is marginally stable. However, if the cylinder is bent, e.g. with a slight sinusoidal perturbation, an otherwise stable configuration starts to oscillate, is triggered into fragmentation and collapses. This previously unstudied behavior allows a filament to fragment at any given scale, as long as it has slight bends. We call this process `geometrical fragmentation'. In our realization the spacing between the cores matches the wavelength of the sinusoidal perturbation, whereas up to now, filaments were thought to be only fragmenting on the characteristical scale set by the mass-to-line ratio. Using first principles, we derive the oscillation period as well as the collapse timescale analytically. To enable a direct comparison with observations, we study the line-of-sight velocity for different inclinations. ...

  20. Successfully introduce maize DNA fragments into rice

    Institute of Scientific and Technical Information of China (English)

    WANGKaizhi

    1994-01-01

    The maize DNA fragments was successfully incorporated into rice by Associate Prof WAN Wenju's research team at Hunan Agricultural College, Changsha, China. The new gene transferring rice is named Genetic Engineered Rice (GER) line.

  1. Modified Empirical Parametrization of Fragmentation Cross Sections

    CERN Document Server

    Sümmerer, K

    2000-01-01

    New experimental data obtained mainly at the GSI/FRS facility allow to modify the empirical parametrization of fragmentation cross sections, EPAX. It will be shown that minor modifications of the parameters lead to a much better reproduction of measured cross sections. The most significant changes refer to the description of fragmentation yields close to the projectile and of the memory effect of neutron-deficient projectiles.

  2. Fragment Length of Circulating Tumor DNA.

    Directory of Open Access Journals (Sweden)

    Hunter R Underhill

    2016-07-01

    Full Text Available Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively. Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively. Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

  3. Fragment Length of Circulating Tumor DNA.

    Science.gov (United States)

    Underhill, Hunter R; Kitzman, Jacob O; Hellwig, Sabine; Welker, Noah C; Daza, Riza; Baker, Daniel N; Gligorich, Keith M; Rostomily, Robert C; Bronner, Mary P; Shendure, Jay

    2016-07-01

    Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA) may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively). Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively). Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

  4. Fragment-based approaches to enzyme inhibition

    OpenAIRE

    Ciulli, Alessio; Abell, Chris

    2007-01-01

    Fragment-based approaches have provided a new paradigm for small-molecule drug discovery. The methodology is complementary to high-throughput screening approaches, starting from fragments of low molecular complexity and high ligand efficiency, and building up to more potent inhibitors. The approach, which depends heavily on a number of biophysical techniques, is now being taken up by more groups in both industry and academia. This article describes key aspects of the process and highlights re...

  5. Avian hepatitis E virus identified in Russian chicken flocks exhibits high genetic divergence based on the ORF2 capsid gene.

    Science.gov (United States)

    Sprygin, A V; Nikonova, Z B; Zinyakov, N G

    2012-10-01

    A total of 79 liver samples from clinically sick and asymptomatic chickens were tested for avian hepatitis E virus (aHEV). Samples were received from 19 farms, five of which tested positive with primers targeting the ORF2 capsid gene. The phylogenetic analysis of a 242-base-pair fragment demonstrated that the Russian aHEV isolates share between 78.2 and 96.2% over the fragment sequenced, whereas the nucleotide sequence identities between the Russian isolates and the other representatives from GeneBank varied from 76.3 to 96.2%. The homology between the studied hepatitis E viruses and swine hepatitis E virus varied between 46.9 to 48.1%. The most divergent isolate aHEV16050 showed homology of 82.6% as compared with the strains in the dendrogram. The three positive hepatitis E virus samples (aHEV16279, aHEV16050 and aHEV18196) did not cluster with the European genotype 3 as expected due to the close location of Russia to Europe, nor did they with the other two genotypes, separating to a distinct branch. The aHEV16211 grouped together with European and Chinese isolates, and the aHEV18198 with Canadian ones.

  6. Avian Colibacillosis and Salmonellosis: A Closer Look at Epidemiology, Pathogenesis, Diagnosis, Control and Public Health Concerns

    Directory of Open Access Journals (Sweden)

    S. M. Lutful Kabir

    2010-01-01

    Full Text Available Avian colibacillosis and salmonellosis are considered to be the major bacterial diseases in the poultry industry world-wide. Colibacillosis and salmonellosis are the most common avian diseases that are communicable to humans. This article provides the vital information on the epidemiology, pathogenesis, diagnosis, control and public health concerns of avian colibacillosis and salmonellosis. A better understanding of the information addressed in this review article will assist the poultry researchers and the poultry industry in continuing to make progress in reducing and eliminating avian colibacillosis and salmonellosis from the poultry flocks, thereby reducing potential hazards to the public health posed by these bacterial diseases.

  7. Access to health information may improve behavior in preventing Avian influenza among women

    Directory of Open Access Journals (Sweden)

    Ajeng T. Endarti

    2011-02-01

    Full Text Available Background: Improving human behavior toward Avian influenza may lessen the chance to be infected by Avian influenza. This study aimed to identify several factors influencing behavior in the community.Method: A cross-sectional study was conducted in July 2008. Behavior regarding Avian influenza was measured by scoring the variables of knowledge, attitude, and practice. Subjects were obtained from the sub district of Limo, in Depok, West Java, which was considered a high risk area for Avian influenza. The heads of household as the sample unit were chosen by multi-stage sampling.Results: Among 387 subjects, 29.5% of them was had good behavior toward Avian influenza. The final model revealed that gender and access to health information were two dominant factors for good behavior in preventing Avian influenza. Compared with men, women had 67% higher risk to have good behavior [adjusted relative risk (RRa = 1.67; 95% confidence interval (CI = 0.92-3.04; P = 0.092]. Compared to those with no access to health information, subjects with access to health information had 3.4 fold increase to good behavior (RRa = 3.40; 95% CI =  0.84-13.76; P = 0.087.Conclusion: Acces to health information concerning Avian influenza was more effective among women in promoting good behavior toward preventing Avian influenza. (Med J Indones 2011; 20:56-61Keywords: avian influenza, behavior, gender, health promotion

  8. A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin

    Institute of Scientific and Technical Information of China (English)

    XU Xing; ZHAO Qi; NORELL Mark; SULLIVAN Corwin; HONE David; ERICKSON Gregory; WANG XiaoLin; HAN FengLu; GUO Yu

    2009-01-01

    Recent fossil discoveries have substantially reduced the morphological gap between non-avian and avian dinosaurs, yet avians including Archaeopteryx differ from non-avian theropods in their limb proportions. In particular, avians have proportionally longer and more robust forelimbs that are capable of supporting a large aerodynamic surface. Here we report on a new maniraptoran dinosaur, Anchiornis huxleyi gen. et sp. nov., based on a specimen collected from Iacustrine deposits of uncertain age in western Liaoning, China. With an estimated mass of 110 grams, Anchiornis is the smallest known non-avian theropod dinosaur. It exhibits some wrist features indicative of high mobility, presaging the wing-folding mechanisms seen in more derived birds and suggesting rapid evolution of the carpus. Otherwise, Anchiornis is intermediate in general morphology between non-avian and avian dinosaurs, particularly with regard to relative forelimb length and thickness, and represents a transitional step toward the avian condition. In contrast with some recent comprehensive phylogenetic analyses, our phylogenetic analysis incorporates subtle morphological variations and recovers a conventional result supporting the monophyly of Avialae.

  9. Immunodominant epitopes mapped by synthetic peptides on the capsid protein of avian hepatitis E virus are non-protective.

    Science.gov (United States)

    Guo, Hailong; Zhou, E M; Sun, Z F; Meng, X J

    2008-03-01

    Avian hepatitis E virus (avian HEV) was recently discovered in chickens with hepatitis-splenomegaly syndrome in the United States. The open reading frame 2 (ORF2) protein of avian HEV has been shown to cross-react with human and swine HEV ORF2 proteins, and immunodominant antigenic epitopes on avian HEV ORF2 protein were identified in the predicted antigenic domains by synthetic peptides. However, whether these epitopes are protective against avian HEV infection has not been investigated. In this study, groups of chickens were immunized with keyhole limpet hemocyanin (KLH)-conjugated peptides and recombinant avian HEV ORF2 antigen followed by challenge with avian HEV virus to assess the protective capacity of these peptides containing the epitopes. While avian HEV ORF2 protein showed complete protection against infection, viremia and fecal virus shedding were found in all peptide-immunized chickens. Using purified IgY from normal, anti-peptide, and anti-avian HEV ORF2 chicken sera, an in-vitro neutralization and in-vivo monitoring assay was performed to further evaluate the neutralizing ability of anti-peptide IgY. Results showed that none of the anti-peptide IgY can neutralize avian HEV in vitro, as viremia, fecal virus shedding, and seroconversion appeared similarly in chickens inoculated with avian HEV mixed with anti-peptide IgY and chickens inoculated with avian HEV mixed with normal IgY. As expected, chickens inoculated with the avian HEV and anti-avian HEV ORF2 IgY mixture did not show detectable avian HEV infection. Taken together, the results of this study demonstrated that immunodominant epitopes on avian HEV ORF2 protein identified by synthetic peptides are non-protective, suggesting protective neutralizing epitope on avian HEV ORF2 may not be linear as is human HEV.

  10. First principles approach to ionicity of fragments

    Energy Technology Data Exchange (ETDEWEB)

    Pilania, Ghanshyam, E-mail: gpilania@lanl.gov; Liu, Xiang-Yang; Valone, Steven M.

    2015-02-20

    Highlights: • A novel first principles approach towards the fragment ionicity. • Constrained DFT and valance charge density decomposition were employed. • Correct dissociation limit achieved for diatomics. • Ionicity is an input parameter for a new class of atomistic potentials. - Abstract: We develop a first principles approach towards the ionicity of fragments. In contrast to the bond ionicity, the fragment ionicity refers to an electronic property of the constituents of a larger system, which may vary from a single atom to a functional group or a unit cell to a crystal. The fragment ionicity is quantitatively defined in terms of the coefficients of contributing charge states in a superposition of valence configurations of the system. Utilizing the constrained density functional theory-based computations, a practical method to compute the fragment ionicity from valence electron charge densities, suitably decomposed according to the Fragment Hamiltonian (FH) model prescription for those electron densities, is presented for the first time. The adopted approach is illustrated using BeO, MgO and CaO diatomic molecules as simple examples. The results are compared and discussed with respect to the bond ionicity scales of Phillips and Pauling.

  11. Session: Avoiding, minimizing, and mitigating avian and bat impacts

    Energy Technology Data Exchange (ETDEWEB)

    Thelander, Carl; Kerlinger, Paul

    2004-09-01

    This session at the Wind Energy and Birds/Bats workshop consisted of two presentations followed by a discussion/question answer period. The session addressed a variety of questions related to avoiding, minimizing, and mitigating the avian and bat impacts of wind power development including: what has been learned from operating turbines and mitigating impacts where they are unavoidable, such as at Altamont Pass WRA, and should there be mitigation measures such as habitat creation or land conservation where impacts occur. Other impact minimization and mitigation approaches discussed included: location and siting evaluations; options for construction and operation of wind facilities; turbine lighting; and the physical alignment/orientation. Titles and authors of the presentations were: 'Bird Fatalities in the Altamont Pass Wind Resource Area: A Case Study, Part II' by Carl Thelander and 'Prevention and Mitigation of Avian Impacts at Wind Power Facilities' by Paul Kerlinger.

  12. Avian influenza in backyard poultry of the Mopti region, Mali.

    Science.gov (United States)

    Molia, Sophie; Traoré, Abdallah; Gil, Patricia; Hammoumi, Saliha; Lesceu, Stéphanie; Servan de Almeida, Renata; Albina, Emmanuel; Chevalier, Véronique

    2010-06-01

    This study reports the first evidence of circulation of avian influenza viruses (AIV) in domestic poultry in Mali. In the Mopti region, where AIV have already been isolated in migratory water birds, we sampled 223 backyard domestic birds potentially in contact with wild birds and found that 3.6% had tracheal or cloacal swabs positive by real-time reverse transcription PCR (rRT-PCR) for type A influenza viruses (IVA) and that 13.7% had sera positive by commercial ELISA test detecting antibodies against IVA. None of the birds positive by rRT-PCR for IVA was positive by rRT-PCR for H5 and H7 subtypes, and none showed any clinical signs therefore indicating the circulation of low pathogenic avian influenza. Unfortunately, no virus isolation was possible. Further studies are needed to assess the temporal evolution of AIV circulation in the Mopti region and its possible correlation with the presence of wild birds.

  13. Avian influenza vaccines against H5N1 'bird flu'.

    Science.gov (United States)

    Li, Chengjun; Bu, Zhigao; Chen, Hualan

    2014-03-01

    H5N1 avian influenza viruses (AIVs) have spread widely to more than 60 countries spanning three continents. To control the disease, vaccination of poultry is implemented in many of the affected countries, especially in those where H5N1 viruses have become enzootic in poultry and wild birds. Recently, considerable progress has been made toward the development of novel avian influenza (AI) vaccines, especially recombinant virus vector vaccines and DNA vaccines. Here, we will discuss the recent advances in vaccine development and use against H5N1 AIV in poultry. Understanding the properties of the available, novel vaccines will allow for the establishment of rational vaccination protocols, which in turn will help the effective control and prevention of H5N1 AI.

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

    CERN Document Server

    Cai, Jianming

    2013-01-01

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

  15. Role of phenotypic diversity in pathogenesis of avian mycoplasmosis.

    Science.gov (United States)

    Noormohammadi, Amir H

    2007-12-01

    The interactions between avian mycoplasmas and their host cells are far more complex than might be anticipated from their apparent structural and functional simplicity. Phenotypic diversity in the form of reversible phase variation, antigenic variation or size variation is an adaptive mechanism that enables avian mycoplasmas to survive in a hostile and highly evolved host. Despite significant similarities between major membrane antigens of Mycoplasma gallisepticum and Mycoplasma synoviae, the molecular mechanisms that mediate phenotypic variation in these two pathogens are completely different. Throughout the years, these mechanisms have evolved side by side with their host immune system and provided mycoplasmas the capacity to colonize, invade and persist in an intricate host. In this article, recent advances in the understanding of the molecular mechanisms of phenotypic variation are reviewed, and implications of such variation in pathogenesis of the disease and development of vaccines and diagnostic assays are outlined.

  16. 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...... and subjected to molecular investigation by sequencing and phylogenetic analysis of the 5.8S and ITS2 ribosomal DNA for species identification. Additionally, snail hosts belonging to the genus Radix were identified by sequencing and phylogenetic analysis of partial ITS2 ribosomal DNA. Three out of 499 snails...

  17. Mimicry and masquerade from the avian visual perspective

    Directory of Open Access Journals (Sweden)

    Mary Caswell STODDARD

    2012-08-01

    Full Text Available Several of the most celebrated examples of visual mimicry, like mimetic eggs laid by avian brood parasites and pala­table insects mimicking distasteful ones, involve signals directed at the eyes of birds. Despite this, studies of mimicry from the avian visual perspective have been rare, particularly with regard to defensive mimicry and masquerade. Defensive visual mimicry, which includes Batesian and Müllerian mimicry, occurs when organisms share a visual signal that functions to deter predators. Masquerade occurs when an organism mimics an inedible or uninteresting object, such as a leaf, stick, or pebble. In this paper, I present five case studies covering diverse examples of defensive mimicry and masquerade as seen by birds. The best-known cases of defensive visual mimicry typically come from insect prey, but birds themselves can exhibit defensive visual mimicry in an attempt to escape mobbing or dissuade avian predators. Using examples of defensive visual mimicry by both insects and birds, I show how quantitative models of avian color, luminance, and pattern vision can be used to enhance our understanding of mimicry in many systems and produce new hypotheses about the evolution and diversity of signals. Overall, I investigate examples of Batesian mimicry (1 and 2, Müllerian mimicry (3 and 4, and masquerade (5 as follows: 1 Polymorphic mimicry in African mocker swallowtail butterflies; 2 Cuckoos mimicking sparrowhawks; 3 Mimicry rings in Neotropical butterflies; 4 Plumage mimicry in toxic pitohuis; and 5 Dead leaf-mimicking butterflies and mantids [Current Zoology 58 (4: 630–648, 2012].

  18. The long view: 40 years of avian leukosis research.

    Science.gov (United States)

    Payne, L N; Nair, V

    2012-01-01

    The present review is aimed at the non-specialist reader and is one of a number being written on important diseases of poultry to celebrate the 40th anniversary of the birth of Avian Pathology, the journal of the World Veterinary Poultry Association. The diseases of the avian leukosis complex have a number of features of distinction. They were the first neoplastic diseases in any species to be shown, 100 years ago, to be transmissible and caused by viruses, and have consequently been studied extensively by biomedical scientists as models for the role of viruses in cancer. They also became, from around the 1920s, the major cause of mortality and economic loss to the developed poultry industry, and were studied by agricultural scientists searching to understand and control them. The remit of the review is to cover research carried out over the 40 years since 1971, when the journal was founded. In this review on avian leukosis, an introductory summary is given of knowledge acquired over the preceding 60 years. Subsequently a selection is provided of discoveries, both fundamental and more applied, that seem to us to be of particular importance and interest. Much of the work was carried out by biomedical scientists interested in cancer. Probably the most significant was the discovery in the avian retroviruses of oncogenes that cause leukosis and other tumours and of their origin from proto-oncogenes in normal cells. These oncogenes are involved in cancer in many species, including chickens and humans. Other work was performed by agricultural scientists interested in poultry disease. Interests of the two groups have overlapped, particularly as a result of a shift of emphasis to molecular biology research.

  19. Avian hepatitis E virus in chickens, Taiwan, 2013.

    Science.gov (United States)

    Hsu, Ingrid W-Y; Tsai, Hsiang-Jung

    2014-01-01

    A previously unidentified strain of avian hepatitis E virus (aHEV) is now endemic among chickens in Taiwan. Analysis showed that the virus is 81.5%-86.5% similar to other aHEVs. In Taiwan, aHEV infection has been reported in chickens without aHEV exposure, suggesting transmission from asymptomatic cases or repeated introduction through an unknown common source(s).

  20. Embryonic development period and the prevalence of avian blood parasites.

    OpenAIRE

    Ricklefs, R E

    1992-01-01

    Variation in prevalence of avian hematozoa is related to taxonomic affiliation at the level of the family or subfamily but not of the genus within families. Prevalence is comparatively insensitive to the influences of habitat and season; however, temperate species have higher incidences of infection than tropical species belonging to the same families. Among taxa of nonraptorial altricial landbirds, hematozoan prevalence is inversely related to the length of the incubation period but shows li...

  1. Evolution of the avian β-defensin and cathelicidin genes

    OpenAIRE

    Cheng, Yuanyuan; Prickett, Michael Dennis; Gutowska, Maria; Kuo, Richard; Belov, Katherine; Burt, David W.

    2015-01-01

    Background β-defensins and cathelicidins are two families of cationic antimicrobial peptides (AMPs) with a broad range of antimicrobial activities that are key components of the innate immune system. Due to their important roles in host defense against rapidly evolving pathogens, the two gene families provide an ideal system for studying adaptive gene evolution. In this study we performed phylogenetic and selection analyses on β-defensins and cathelicidins from 53 avian species representing 3...

  2. Presence of avian pneumovirus subtypes A and B in Japan.

    Science.gov (United States)

    Mase, Masaji; Yamaguchi, Shigeo; Tsukamoto, Kenji; Imada, Tadao; Imai, Kunitoshi; Nakamura, Kikuyasu

    2003-01-01

    Four avian pneumovirus (APV) isolates from chickens clinically diagnosed with swollen head syndrome were genetically characterized as to the subtypes of the virus in Japan. The results of reverse transcriptase-polymerase chain reactions based on subtype-specific primers and direct sequence analysis of G genes indicated subtypes A and B but not C or D of APV were present in Japan. Several routes or sources are conceivable for APV to invade into Japan.

  3. Neurobehavioral teratogenicity of perfluorinated alkyls in an avian model

    OpenAIRE

    Pinkas, Adi; Slotkin, Theodore A.; Brick-Turin, Yael; Van der Zee, Eddy A.; Yanai, Joseph

    2010-01-01

    Perfluorinated alkyls are widely-used agents that accumulate in ecosystems and organisms because of their slow rate of degradation. There is increasing concern that these agents may be developmental neurotoxicants and the present study was designed to develop an avian model for the neurobehavioral teratogenicity of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Fertilized chicken eggs were injected with 5 or 10 mg/kg of either compound on incubation day 0. On the day of h...

  4. Mimicry and masquerade from the avian visual perspective

    Institute of Scientific and Technical Information of China (English)

    Mary Caswell STODDARD

    2012-01-01

    Several of the most celebrated examples of visual mimicry,like mimetic eggs laid by avian brood parasites and palatable insects mimicking distasteful ones,involve signals directed at the eyes of birds.Despite this,studies of mimicry from the avian visual perspective have been rare,particularly with regard to defensive mimicry and masquerade.Defensive visual mimicry,which includes Batesian and Müllerian mimicry,occurs when organisms share a visual signal that functions to deter predators.Masquerade occurs when an organism mimics an inedible or uninteresting object,such as a leaf,stick,or pebble.In this paper,I present five case studies covering diverse examples of defensive mimicry and masquerade as seen by birds.The best-known cases of defensive visual mimicry typically come from insect prey,but birds themselves can exhibit defensive visual mimicry in an attempt to escape mobbing or dissuade avian predators.Using examples of defensive visual mimicry by both insects and birds,I show how quantitative models of avian color,luminance,and pattern vision can be used to enhance our understanding of mimicry in many systems and produce new hypotheses about the evolution and diversity of signals.Overall,I investigate examples of Batesian mimicry (1 and 2),Müllerian mimicry (3 and 4),and masquerade (5) as follows:1) Polymorphic mimicry in African mocker swallowtail butterflies; 2) Cuckoos mimicking sparrowhawks; 3) Mimicry rings in Neotropical butterflies; 4) Plumage mimicry in toxic pitohuis; and 5) Dead leaf-mimicking butterflies and mantids.

  5. Recombination in Avian Gamma-Coronavirus Infectious Bronchitis Virus

    OpenAIRE

    2011-01-01

    Recombination in the family Coronaviridae has been well documented and is thought to be a contributing factor in the emergence and evolution of different coronaviral genotypes as well as different species of coronavirus. However, there are limited data available on the frequency and extent of recombination in coronaviruses in nature and particularly for the avian gamma-coronaviruses where only recently the emergence of a turkey coronavirus has been attributed solely to recombination. In this ...

  6. Fragment library design: using cheminformatics and expert chemists to fill gaps in existing fragment libraries.

    Science.gov (United States)

    Kutchukian, Peter S; So, Sung-Sau; Fischer, Christian; Waller, Chris L

    2015-01-01

    Fragment based screening (FBS) has emerged as a mainstream lead discovery strategy in academia, biotechnology start-ups, and large pharma. As a prerequisite of FBS, a structurally diverse library of fragments is desirable in order to identify chemical matter that will interact with the range of diverse target classes that are prosecuted in contemporary screening campaigns. In addition, it is also desirable to offer synthetically amenable starting points to increase the probability of a successful fragment evolution through medicinal chemistry. Herein we describe a method to identify biologically relevant chemical substructures that are missing from an existing fragment library (chemical gaps), and organize these chemical gaps hierarchically so that medicinal chemists can efficiently navigate the prioritized chemical space and subsequently select purchasable fragments for inclusion in an enhanced fragment library.

  7. Implications of promiscuous Pim-1 kinase fragment inhibitor hydrophobic interactions for fragment-based drug design.

    Science.gov (United States)

    Good, Andrew C; Liu, Jinyu; Hirth, Bradford; Asmussen, Gary; Xiang, Yibin; Biemann, Hans-Peter; Bishop, Kimberly A; Fremgen, Trisha; Fitzgerald, Maria; Gladysheva, Tatiana; Jain, Annuradha; Jancsics, Katherine; Metz, Markus; Papoulis, Andrew; Skerlj, Renato; Stepp, J David; Wei, Ronnie R

    2012-03-22

    We have studied the subtleties of fragment docking and binding using data generated in a Pim-1 kinase inhibitor program. Crystallographic and docking data analyses have been undertaken using inhibitor complexes derived from an in-house surface plasmon resonance (SPR) fragment screen, a virtual needle screen, and a de novo designed fragment inhibitor hybrid. These investigations highlight that fragments that do not fill their binding pocket can exhibit promiscuous hydrophobic interactions due to the lack of steric constraints imposed on them by the boundaries of said pocket. As a result, docking modes that disagree with an observed crystal structure but maintain key crystallographically observed hydrogen bonds still have potential value in ligand design and optimization. This observation runs counter to the lore in fragment-based drug design that all fragment elaboration must be based on the parent crystal structure alone.

  8. Force-velocity properties of two avian hindlimb muscles.

    Science.gov (United States)

    Nelson, Frank E; Gabaldón, Annette M; Roberts, Thomas J

    2004-04-01

    Recent work has provided measurements of power output in avian skeletal muscles during running and flying, but little is known about the contractile properties of avian skeletal muscle. We used an in situ preparation to characterize the force-velocity properties of two hind limb muscles, the lateral gastrocnemius (LG) and peroneus longus (PL), in Wild Turkeys (Meleagris gallopavo). A servomotor measured shortening velocity for at least six different loads over the plateau region of the length-tension curve. The Hill equation was fit to the data to determine maximum shortening velocity and peak instantaneous power. Maximum unloaded shortening velocity was 13.0+/-1.6 L s(-1) for the LG muscle and 14.8+/-1.0 L s(-1) for the PL muscle (mean+/-S.E.M.). These velocities are within the range of values published for reptilian and mammalian muscles. Values recorded for maximum isometric force per cross-sectional area, 271+/-28 kPa for the LG and 257+/-30.5 kPa for the PL, and peak instantaneous power output, 341.7+/-36.4 W kg(-1) for the LG and 319.4+/-42.5 W kg(-1) for the PL, were also within the range of published values for vertebrate muscle. The force-velocity properties of turkey LG and PL muscle do not reveal any extreme differences in the mechanical potential between avian and other vertebrate muscle.

  9. Avian bornavirus in the urine of infected birds

    Directory of Open Access Journals (Sweden)

    Villalobos AR

    2012-06-01

    Full Text Available J Jill Heatley,1 Alice R Villalobos21Zoological Medicine, 2Department of Nutrition & Food Science, Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, College Station, TX, USAAbstract: Avian bornavirus (ABV causes proventricular dilatation disease in multiple avian species. In severe clinical disease, the virus, while primarily neurotropic, can be detected in many organs, including the kidneys. We postulated that ABV could be shed by the kidneys and found in the urine of infected birds. Immunohistochemical staining demonstrated viral N and P proteins of ABV within the renal tubules. We adapted a nonsurgical method of urine collection for use in parrots known to be shedding ABV in their droppings. We obtained urine without feces, and results were compared with swabs of fresh voided feces. Reverse transcription–polymerase chain reaction assay performed on these paired samples from five birds indicated that ABV was shed in quantity in the urine of infected birds, and a single sample was urine-positive and fecal-negative. We suggest that urine sampling may be a superior sample for detection of birds shedding ABV, and advocate that additional birds, known to be shedding or infected with ABV, should be investigated via this method.Keywords: avian bornavirus, Psittaciformes, parrot, urine, proventricular dilatation disease

  10. Avian conservation practices strengthen ecosystem services in California vineyards.

    Science.gov (United States)

    Jedlicka, Julie A; Greenberg, Russell; Letourneau, Deborah K

    2011-01-01

    Insectivorous Western Bluebirds (Sialia mexicana) occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua) were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services.

  11. Avian conservation practices strengthen ecosystem services in California vineyards.

    Directory of Open Access Journals (Sweden)

    Julie A Jedlicka

    Full Text Available Insectivorous Western Bluebirds (Sialia mexicana occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services.

  12. Review of avian mortality studies at concentrating solar power plants

    Science.gov (United States)

    Ho, Clifford K.

    2016-05-01

    This paper reviews past and current avian mortality studies at concentrating solar power (CSP) plants and facilities including Solar One in California, the Solar Energy Development Center in Israel, Ivanpah Solar Electric Generating System in California, Crescent Dunes in Nevada, and Gemasolar in Spain. Findings indicate that the leading causes of bird deaths at CSP plants are from collisions (primarily with reflective surfaces; i.e., heliostats) and singeing caused by concentrated solar flux. Safe irradiance levels for birds have been reported to range between 4 and 50 kW/m2. Above these levels, singeing and irreversible damage to the feathers can occur. Despite observations of large numbers of "streamers" in concentrated flux regions and reports that suggest these streamers indicate complete vaporization of birds, analyses in this paper show that complete vaporization of birds is highly improbable, and the observed streamers are likely due to insects flying into the concentrated flux. The levelized avian mortality rate during the first year of operation at Ivanpah was estimated to be 0.7 - 3.5 fatalities per GWh, which is less than the levelized avian mortality reported for fossil fuel plants but greater than that for nuclear and wind power plants. Mitigation measures include acoustic, visual, tactile, and chemosensory deterrents to keep birds away from the plant, and heliostat aiming strategies that reduce the solar flux during standby.

  13. Avian Influenza: a global threat needing a global solution.

    Science.gov (United States)

    Koh, Gch; Wong, Ty; Cheong, Sk; Koh, Dsq

    2008-11-13

    There have been three influenza pandemics since the 1900s, of which the 1919-1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI) is endemic in Asia as a result of unregulated poultry rearing in rural areas. Such birds often live in close proximity to humans and this increases the chance of genetic re-assortment between avian and human influenza viruses which may produce a mutant strain that is easily transmitted between humans. Once this happens, a global pandemic is likely. Unlike SARS, a person with influenza infection is contagious before the onset of case-defining symptoms which limits the effectiveness of case isolation as a control strategy. Researchers have shown that carefully orchestrated of public health measures could potentially limit the spread of an AI pandemic if implemented soon after the first cases appear. To successfully contain and control an AI pandemic, both national and global strategies are needed. National strategies include source surveillance and control, adequate stockpiles of anti-viral agents, timely production of flu vaccines and healthcare system readiness. Global strategies such as early integrated response, curbing the disease outbreak at source, utilization of global resources, continuing research and open communication are also critical.

  14. Dinosaurian growth patterns and rapid avian growth rates.

    Science.gov (United States)

    Erickson, G M; Rogers, K C; Yerby, S A

    2001-07-26

    Did dinosaurs grow in a manner similar to extant reptiles, mammals or birds, or were they unique? Are rapid avian growth rates an innovation unique to birds, or were they inherited from dinosaurian precursors? We quantified growth rates for a group of dinosaurs spanning the phylogenetic and size diversity for the clade and used regression analysis to characterize the results. Here we show that dinosaurs exhibited sigmoidal growth curves similar to those of other vertebrates, but had unique growth rates with respect to body mass. All dinosaurs grew at accelerated rates relative to the primitive condition seen in extant reptiles. Small dinosaurs grew at moderately rapid rates, similar to those of marsupials, but large species attained rates comparable to those of eutherian mammals and precocial birds. Growth in giant sauropods was similar to that of whales of comparable size. Non-avian dinosaurs did not attain rates like those of altricial birds. Avian growth rates were attained in a stepwise fashion after birds diverged from theropod ancestors in the Jurassic period.

  15. 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 (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.

  16. The cuticle modulates ultraviolet reflectance of avian eggshells

    Directory of Open Access Journals (Sweden)

    Daphne C. Fecheyr-Lippens

    2015-07-01

    Full Text Available Avian eggshells are variedly coloured, yet only two pigments, biliverdin and protoporphyrin IX, are known to contribute to the dramatic diversity of their colours. By contrast, the contributions of structural or other chemical components of the eggshell are poorly understood. For example, unpigmented eggshells, which appear white to the human eye, vary in their ultraviolet (UV reflectance, which may be detectable by birds. We investigated the proximate mechanisms for the variation in UV-reflectance of unpigmented bird eggshells using spectrophotometry, electron microscopy, chemical analyses, and experimental manipulations. We specifically tested how UV-reflectance is affected by the eggshell cuticle, the outermost layer of most avian eggshells. The chemical dissolution of the outer eggshell layers, including the cuticle, increased UV-reflectance for only eggshells that contained a cuticle. Our findings demonstrate that the outer eggshell layers, including the cuticle, absorb UV-light, probably because they contain higher levels of organic components and other chemicals, such as calcium phosphates, compared to the predominantly calcite-based eggshell matrix. These data highlight the need to examine factors other than the known pigments in studies of avian eggshell colour.

  17. Clinical features of avian influenza in Egyptian patients.

    Science.gov (United States)

    Ashour, Maamoun Mohamad; Khatab, Adel Mahmoud; El-Folly, Runia Fouad; Amer, Wegdan Ahmad Fouad

    2012-08-01

    The clinical manifestations associated with H5N1 infection in humans range from asymptomatic infection to mild upper respiratory illness, severe pneumonia, and multiple organ failure. The ratio of symptomatic cases to asymptomatic cases is not known, because it is not possible to precisely define the number of asymptomatic cases. A total of 97 cases suffering from avian flu were suspected based on history taking, demographic data, clinical manifestations, laboratory and radiological investigations. The followings were done for all cases; complete blood picture (differential leucocytic count), coagulation profile, renal and liver function tests. H5N1 influenza virus was diagnosed thorough PCR technique. Changes in arterial blood gases and repeated chest X-rays were reported frequently. All patients were given specific antiviral therapy (oseltamivir). The study described the clinical picture and laboratory results of 81 confirmed avian influenza human cases in an Egyptian hospital (Abassia chest hospital), and reviewed the avian influenza current situation covering from March 2006 to June 2009 with very high pick in the first half of 2009. The significant apparent symptoms were fever as initial and main symptom (93.75%), followed by shortness of breathing (73%), cough (66.6%), muscle & joint pain (60%) and sore throat (40%).

  18. Active surveillance for avian influenza virus, Egypt, 2010-2012.

    Science.gov (United States)

    Kayali, Ghazi; Kandeil, Ahmed; El-Shesheny, Rabeh; Kayed, Ahmed S; Gomaa, Mokhtar M; Maatouq, Asmaa M; Shehata, Mahmoud M; Moatasim, Yassmin; Bagato, Ola; Cai, Zhipeng; Rubrum, Adam; Kutkat, Mohamed A; McKenzie, Pamela P; Webster, Robert G; Webby, Richard J; Ali, Mohamed A

    2014-04-01

    Continuous circulation of influenza A(H5N1) virus among poultry in Egypt has created an epicenter in which the viruses evolve into newer subclades and continue to cause disease in humans. To detect influenza viruses in Egypt, since 2009 we have actively surveyed various regions and poultry production sectors. From August 2010 through January 2013, >11,000 swab samples were collected; 10% were positive by matrix gene reverse transcription PCR. During this period, subtype H9N2 viruses emerged, cocirculated with subtype H5N1 viruses, and frequently co-infected the same avian host. Genetic and antigenic analyses of viruses revealed that influenza A(H5N1) clade 2.2.1 viruses are dominant and that all subtype H9N2 viruses are G1-like. Cocirculation of different subtypes poses concern for potential reassortment. Avian influenza continues to threaten public and animal health in Egypt, and continuous surveillance for avian influenza virus is needed.

  19. Secondary cartilage revealed in a non-avian dinosaur embryo.

    Directory of Open Access Journals (Sweden)

    Alida M Bailleul

    Full Text Available The skull and jaws of extant birds possess secondary cartilage, a tissue that arises after bone formation during embryonic development at articulations, ligamentous and muscular insertions. Using histological analysis, we discovered secondary cartilage in a non-avian dinosaur embryo, Hypacrosaurus stebingeri (Ornithischia, Lambeosaurinae. This finding extends our previous report of secondary cartilage in post-hatching specimens of the same dinosaur species. It provides the first information on the ontogeny of avian and dinosaurian secondary cartilages, and further stresses their developmental similarities. Secondary cartilage was found in an embryonic dentary within a tooth socket where it is hypothesized to have arisen due to mechanical stresses generated during tooth formation. Two patterns were discerned: secondary cartilage is more restricted in location in this Hypacrosaurus embryo, than it is in Hypacrosaurus post-hatchlings; secondary cartilage occurs at far more sites in bird embryos and nestlings than in Hypacrosaurus. This suggests an increase in the number of sites of secondary cartilage during the evolution of birds. We hypothesize that secondary cartilage provided advantages in the fine manipulation of food and was selected over other types of tissues/articulations during the evolution of the highly specialized avian beak from the jaws of their dinosaurian ancestors.

  20. Avian cathelicidins: paradigms for the development of anti-infectives.

    Science.gov (United States)

    van Dijk, A; Molhoek, E M; Bikker, F J; Yu, P-L; Veldhuizen, E J A; Haagsman, H P

    2011-11-21

    The broad-spectrum defense system based on host defense peptides (HDPs) is evolutionary very old and many invertebrates rely on this system for protection from bacterial infections. However, in vertebrates the system remained important in spite of the superposition of a very sophisticated adaptive immune system. The cathelicidins comprise a major group of HDPs in mammals. About six years ago it was first described that cathelicidins are also present in birds. Here we review the properties and biological activities of the recently discovered avian cathelicidins and their potential to be used as a paradigm for the development of anti-infectives. Like the mammalian cathelicidins, avian cathelicidins exert direct antimicrobial activities but can also selectively boost host immune responses by regulation of cytokine production and recruitment of immune cells. In addition, it was found that chicken cathelicidins bind endotoxins and dampen the endotoxin-mediated inflammatory response. Molecular dissection has allowed identification of different structural elements involved in bacterial killing and immunomodulation. These studies have enabled the design of small HDP-based antibiotics with specific functions, i.e. having primarily immunomodulatory or antimicrobial activities. Since the immunomodulatory effects may, to a certain degree, be species-specific, we hypothesize that poultry-specific antibiotics can be developed based on avian cathelicidins.

  1. Characterization of avian influenza H5N1 virosome

    Directory of Open Access Journals (Sweden)

    Chatchai Sarachai

    2014-04-01

    Full Text Available The purpose of this study was to prepare and characterize virosome containing envelope proteins of the avian influenza (H5N1 virus. The virosome was prepared by the solubilization of virus with octaethyleneglycol mono (n-dodecyl ether (C12E8 followed by detergent removal with SM2 Bio-Beads. Biochemical analysis by SDS-PAGE and western blotting, indicated that avian influenza H5N1 virosome had similar characteristics to the parent virus and contained both the hemagglutinin (HA, 60-75 kDa and neuraminidase (NA, 220 kDa protein, with preserved biological activity, such as hemagglutination activity. The virosome structure was analyzed by negative stained transmission electron microscope (TEM demonstrated that the spherical shapes of vesicles with surface glycoprotein spikes were harbored. In conclusion, the biophysical properties of the virosome were similar to the parent virus, and the use of octaethyleneglycol mono (n-dodecyl ether to solubilize viral membrane, followed by removal of detergent using polymer beads adsorption (Bio-Beads SM2 was the preferable method for obtaining avian influenza virosome. The outcome of this study might be useful for further development veterinary virus vaccines.

  2. Invariant Object Recognition Based on Extended Fragments

    Directory of Open Access Journals (Sweden)

    Evgeniy eBart

    2012-08-01

    Full Text Available Visual appearance of natural objects is profoundly affected by viewing conditions such as viewpoint and illumination. Human subjects can nevertheless compensate well for variations in these viewing conditions. The strategies that the visual system uses to accomplish this are largely unclear. Previous computational studies have suggested that in principle, certain types of object fragments (rather than whole objects can be used for invariant recognition. However, whether the human visual system is actually capable of using this strategy remains unknown. Here, we show that human observers can achieve illumination invariance by using object fragments that carry the relevant information. To determine this, we have used novel, but naturalistic, 3-D visual objects called ‘digital embryos’. Using novel instances of whole embryos, not fragments, we trained subjects to recognize individual embryos across illuminations. We then tested the illumination-invariant object recognition performance of subjects using fragments. We found that the performance was strongly correlated with the mutual information (MI of the fragments, provided that MI value took variations in illumination into consideration. This correlation was not attributable to any systematic differences in task difficulty between different fragments. These results reveal two important principles of invariant object recognition. First, the subjects can achieve invariance at least in part by compensating for the changes in the appearance of small local features, rather than of whole objects. Second, the subjects do not always rely on generic or pre-existing invariance of features (i.e., features whose appearance remains largely unchanged by variations in illumination, and are capable of using learning to compensate for appearance changes when necessary. These psychophysical results closely fit the predictions of earlier computational studies of fragment-based invariant object recognition.

  3. Okazaki fragment maturation: nucleases take centre stage

    Institute of Scientific and Technical Information of China (English)

    Li Zheng; Binghui Shen

    2011-01-01

    Completion of lagging strand DNA synthesis requires processing of up to 50 million Okazaki fragments per cell cycle in mammalian cells. Even in yeast, the Okazaki fragment maturation happens approximately a million times during a singte round of DNA replication. Therefore, efficient processing of Okazaki fragments is vital for DNA replication and cell proliferation. During this process,primase-synthesized RNA/DNA primers are removed, and Okazaki fragments are joined into an intact lagging strand DNA. The processing of RNA/DNA primers requires a group of structure-specific nucleases typified by flap endonuclease 1 (FEN1). Here, we summarize the distinct roles of these nucleases in different pathways for removal of RNA/DNA primers. Recent findings reveal that Okazaki fragment maturation is highly coordinated. The dynamic interactions of polymerase δ, FEN1 and DNA ligase I with proliferating cell nuclear antigen allow these enzymes to act sequentially during Okazaki fragment maturation. Such protein-protein interactions may be regulated by post-translational modifications. We also discuss studies using mutant mouse models that suggest two distinct cancer etiological mechanisms arising from defects in different steps of Okazaki fragment maturation.Mutations that affect the efficiency of RNA primer removal may result in accumulation of unligated nicks and DNA double-strand breaks. These DNA strand breaks can cause varying forms of chromosome aberrations, contributing to development of cancer that associates with aneuploidy and gross chromosomal rearrangement. On the other hand, mutations that impair editing out of polymerase o incorporation errors result in cancer displaying a strong mutator phenotype.

  4. Nonlinear dynamical model and response of avian cranial kinesis.

    Science.gov (United States)

    Meekangvan, Preeda; A Barhorst, Alan; Burton, Thomas D; Chatterjee, Sankar; Schovanec, Lawrence

    2006-05-01

    All modern birds have kinetic skulls in which the upper bill can move relative to the braincase, but the biomechanics and motion dynamics of cranial kinesis in birds are poorly understood. In this paper, we model the dynamics of avian cranial kinesis, such as prokinesis and proximal rhynchokinesis in which the upper jaw pivots around the nasal-frontal (N-F) hinge. The purpose of this paper is to present to the biological community an approach that demonstrates the application of sophisticated predictive mathematical modeling tools to avian kinesis. The generality of the method, however, is applicable to the advanced study of the biomechanics of other skeletal systems. The paper begins with a review of the relevant biological literature as well as the essential morphology of avian kinesis, especially the mechanical coupling of the upper and lower jaw by the postorbital ligament. A planar model of the described bird jaw morphology is then developed that maintains the closed kinematic topology of the avian jaw mechanism. We then develop the full nonlinear equations of motion with the assumption that the M. protractor pterygoideus and M. depressor mandibulae act on the quadrate as a pure torque, and the nasal frontal hinge is elastic with damping. The mechanism is shown to be a single degree of freedom device due to the holonomic constraints present in the quadrate-jugal bar-upper jaw-braincase-quadrate kinematic chain as well as the quadrate-lower jaw-postorbital ligament-braincase-quadrate kinematic chain. The full equations are verified via simulation and animation using the parameters of a Grey Heron (Ardea cinerea). Next we develop a simplified analytical model of the equations by power series expansion. We demonstrate that this model reproduces the dynamics of the full model to a high degree of fidelity. We proceed to use the harmonic balance technique to develop the frequency response characteristics of the jaw mechanism. It is shown that this avian cranial

  5. Replication and adaptive mutations of low pathogenic avian influenza viruses in tracheal organ cultures of different avian species.

    Directory of Open Access Journals (Sweden)

    Henning Petersen

    Full Text Available Transmission of avian influenza viruses (AIV between different avian species may require genome mutations that allow efficient virus replication in a new species and could increase virulence. To study the role of domestic poultry in the evolution of AIV we compared replication of low pathogenic (LP AIV of subtypes H9N2, H7N7 and H6N8 in tracheal organ cultures (TOC and primary embryo fibroblast cultures of chicken, turkey, Pekin duck and homing pigeon. Virus strain-dependent and avian species-related differences between LPAIV were observed in growth kinetics and induction of ciliostasis in TOC. In particular, our data demonstrate high susceptibility to LPAIV of turkey TOC contrasted with low susceptibility of homing pigeon TOC. Serial virus passages in the cells of heterologous host species resulted in adaptive mutations in the AIV genome, especially in the receptor-binding site and protease cleavage site of the hemagglutinin. Our data highlight differences in susceptibility of different birds to AIV viruses and emphasizes potential role of poultry in the emergence of new virus variants.

  6. Different intracellular distribution of avian reovirus core protein sigmaA in cells of avian and mammalian origin

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez-Iglesias, Lorena; Lostale-Seijo, Irene; Martinez-Costas, Jose [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain); Benavente, Javier, E-mail: franciscojavier.benavente@usc.es [Departamento de Bioquimica y Biologia Molecular, Facultad de Farmacia, y Centro Singular de Investigacion en Quimica Biologica y Materiales Moleculares (CIQUS), Universidad de Santiago de Compostela, 15782-Santiago de Compostela (Spain)

    2012-10-25

    A comparative analysis of the intracellular distribution of avian reovirus (ARV) core protein sigmaA in cells of avian and mammalian origin revealed that, whereas the viral protein accumulates in the cytoplasm and nucleolus of avian cells, most sigmaA concentrates in the nucleoplasm of mammalian cells in tight association with the insoluble nuclear matrix fraction. Our results further showed that sigmaA becomes arrested in the nucleoplasm of mammalian cells via association with mammalian cell-specific factors and that this association prevents nucleolar targeting. Inhibition of RNA polymerase II activity, but not of RNA polymerase I activity, in infected mammalian cells induces nucleus-to-cytoplasm sigmaA translocation through a CRM1- and RanGTP-dependent mechanism, yet a heterokaryon assay suggests that sigmaA does not shuttle between the nucleus and cytoplasm. The scarcity of sigmaA in cytoplasmic viral factories of infected mammalian cells could be one of the factors contributing to limited ARV replication in mammalian cells.

  7. Serological prevalence, genetic identification, and characterization of the first strains of avian hepatitis E virus from chickens in Korea.

    Science.gov (United States)

    Kwon, Hyuk Moo; Sung, Haan Woo; Meng, Xiang-Jin

    2012-10-01

    Avian hepatitis E virus (avian HEV) is associated with hepatitis-splenomegaly (HS) syndrome or big liver and spleen disease in chickens. At least three genotypes of avian HEV have been identified from chickens worldwide. A total of 297 serum samples collected from chickens in 35 flocks in Korea were tested for avian HEV antibody with an enzyme-linked immunosorbent assay. The results showed that approximately 57 % of chicken flocks and 28 % of chickens from Korea were positive for antibodies to avian HEV. Thirteen pooled fecal samples from chickens were tested for avian HEV RNA by RT-PCR, and three fecal samples were positive. The partial helicase and capsid genes of the Korean avian HEV isolates were determined, and sequence analyses revealed that the Korean avian HEV isolates were clustered together and closely related to the genotype 1 avian HEV from Australia. The complete genomic sequence of a Korean avian HEV strain HH-F9 from a broiler breeder was determined, and shown to be 6,653 nt in length, excluding the poly (A) tail, which is 1 nt shorter than the prototype avian HEV from chicken with HS syndrome in the United States. Compared to the full-length sequences of other 5 known avian HEV strains worldwide, the Korean avian HEV shared approximately 83-97 % nucleotide sequence identity. The finding that Korean avian HEV belongs to genotype 1 avian HEV which was previously identified only from chickens in Australia has significant implication in understanding the global epidemiology of avian HEV.

  8. Correlation measurements of fission-fragment properties

    Directory of Open Access Journals (Sweden)

    Oberstedt A.

    2010-10-01

    Full Text Available For the development of future nuclear fission applications and for a responsible handling of nuclear waste the a-priori assessment of the fission-fragments’ heat production and toxicity is a fundamental necessity. The success of an indispensable modelling of the fission process strongly depends on a good understanding of the particular mechanism of scission, the mass fragmentation and partition of excitation energy. Experimental observables are fission-fragment properties like mass- and energy-distributions, and the prompt neutron as well as γ-ray multiplicities and emission spectra. The latter quantities should preferably be known as a function of fragment mass and excitation energy. Those data are highly demanded as published by the OECD-NEA in its high priority data request list. With the construction of the double (v, E spectrometer VERDI we aim at measuring pre- and post-neutron masses directly and simultaneously to avoid prompt neutron corrections. From the simultaneous measurement of pre- and post-neutron fission-fragment data the prompt neutron multiplicity may then be inferred fully correlated with fragment mass yield and total kinetic energy. Using an ultra-fast fission event trigger spectral prompt fission γ-ray measurements may be performed. For that purpose recently developed lanthanum-halide detectors, with excellent timing characteristics, were coupled to the VERDI spectrometer allowing for a very good discrimination of fission γ-rays and prompt neutrons due to their different time-of-flight.

  9. Global-Scale Patterns of Forest Fragmentation

    Directory of Open Access Journals (Sweden)

    Kurt Riitters

    2000-12-01

    Full Text Available We report an analysis of forest fragmentation based on 1-km resolution land-cover maps for the globe. Measurements in analysis windows from 81 km 2 (9 x 9 pixels, "small" scale to 59,049 km 2 (243 x 243 pixels, "large" scale were used to characterize the fragmentation around each forested pixel. We identified six categories of fragmentation (interior, perforated, edge, transitional, patch, and undetermined from the amount of forest and its occurrence as adjacent forest pixels. Interior forest exists only at relatively small scales; at larger scales, forests are dominated by edge and patch conditions. At the smallest scale, there were significant differences in fragmentation among continents; within continents, there were significant differences among individual forest types. Tropical rain forest fragmentation was most severe in North America and least severe in Europe-Asia. Forest types with a high percentage of perforated conditions were mainly in North America (five types and Europe-Asia (four types, in both temperate and subtropical regions. Transitional and patch conditions were most common in 11 forest types, of which only a few would be considered as "naturally patchy" (e.g., dry woodland. The five forest types with the highest percentage of interior conditions were in North America; in decreasing order, they were cool rain forest, coniferous, conifer boreal, cool mixed, and cool broadleaf.

  10. Rock fragmentation control in opencast blasting

    Directory of Open Access Journals (Sweden)

    P.K. Singh

    2016-04-01

    Full Text Available The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A high-speed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

  11. 9 CFR 146.14 - Diagnostic surveillance program for H5/H7 low pathogenic avian influenza.

    Science.gov (United States)

    2010-01-01

    .../H7 low pathogenic avian influenza. 146.14 Section 146.14 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...

  12. 75 FR 69046 - Notice of Determination of the High Pathogenic Avian Influenza Subtype H5N1 Status of Czech...

    Science.gov (United States)

    2010-11-10

    ... Pathogenic Avian Influenza Subtype H5N1 Status of Czech Republic and Sweden AGENCY: Animal and Plant Health... the highly pathogenic avian influenza (HPAI) subtype H5N1 status of the Czech Republic and Sweden... status of the Czech Republic and Sweden relative to highly pathogenic avian influenza (HPAI) subtype...

  13. New information on photon fragmentation functions

    Science.gov (United States)

    Klasen, Michael; König, Florian

    2014-08-01

    Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of the prompt photons produced simultaneously in hard collisions of quarks and gluons, mostly through their fragmentation. In this paper, we demonstrate that PHENIX data on photons produced in proton-proton collisions with low transverse momenta allow to extract new information on this fragmentation process. While existing data do not yet convincingly favor one parameterization (BFG II) over the two other frequently used photon fragmentation functions (BFG I and GRV NLO), the data sets recorded by PHENIX and STAR at BNL RHIC in 2013 with tenfold higher statistics should allow for such an analysis.

  14. New information on photon fragmentation functions

    Energy Technology Data Exchange (ETDEWEB)

    Klasen, Michael; Koenig, Florian [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Theoretische Physik, Muenster (Germany)

    2014-08-15

    Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of the prompt photons produced simultaneously in hard collisions of quarks and gluons, mostly through their fragmentation. In this paper, we demonstrate that PHENIX data on photons produced in proton-proton collisions with low transverse momenta allow one to extract new information on this fragmentation process. While existing data do not yet convincingly favor one parameterization (BFG II) over the two other frequently used photon fragmentation functions (BFG I and GRV NLO), the data sets recorded by PHENIX and STAR at BNL RHIC in 2013 with tenfold higher statistics should allow for such an analysis. (orig.)

  15. Fragmentation of colliding planetesimals with water content

    CERN Document Server

    Maindl, Thomas I; Schäfer, Christoph; Speith, Roland

    2014-01-01

    We investigate the outcome of collisions of Ceres-sized planetesimals composed of a rocky core and a shell of water ice. These collisions are not only relevant for explaining the formation of planetary embryos in early planetary systems, but also provide insight into the formation of asteroid families and possible water transport via colliding small bodies. Earlier studies show characteristic collision velocities exceeding the bodies' mutual escape velocity which - along with the distribution of the impact angles - cover the collision outcome regimes 'partial accretion', 'erosion', and 'hit-and-run' leading to different expected fragmentation scenarios. Existing collision simulations use bodies composed of strengthless material; we study the distribution of fragments and their water contents considering the full elasto-plastic continuum mechanics equations also including brittle failure and fragmentation.

  16. Flow angle from intermediate mass fragment measurements

    Energy Technology Data Exchange (ETDEWEB)

    Rami, F.; Crochet, P.; Dona, R.; De Schauenburg, B.; Wagner, P.; Alard, J.P.; Andronic, A.; Basrak, Z.; Bastid, N.; Belyaev, I.; Bendarag, A.; Berek, G.; Best, D.; Caplar, R.; Devismes, A.; Dupieux, P.; Dzelalija, M.; Eskef, M.; Fodor, Z.; Gobbi, A.; Grishkin, Y.; Herrmann, N.; Hildenbrand, K.D.; Hong, B.; Kecskemeti, J.; Kirejczyk, M.; Korolija, M.; Kotte, R.; Lebedev, A.; Leifels, Y.; Merlitz, H.; Mohren, S.; Moisa, D.; Neubert, W.; Pelte, D.; Petrovici, M.; Pinkenburg, C.; Plettner, C.; Reisdorf, W.; Schuell, D.; Seres, Z.; Sikora, B.; Simion, V.; Siwek-Wilczynska, K.; Stoicea, G.; Stockmeir, M.; Vasiliev, M.; Wisniewski, K.; Wohlfarth, D.; Yushmanov, I.; Zhilin, A

    1999-02-15

    Directed sideward flow of light charged particles and intermediate mass fragments was measured in different symmetric reactions at bombarding energies from 90 to 800 A MeV. The flow parameter is found to increase with the charge of the detected fragment up to Z = 3-4 and then turns into saturation for heavier fragments. Guided by simple simulations of an anisotropic expanding thermal source, we show that the value at saturation can provide a good estimate of the flow angle, {theta}{sub flow}, in the participant region. It is found that {theta}{sub flow} depends strongly on the impact parameter. The excitation function of {theta}{sub flow} reveals striking deviations from the ideal hydrodynamical scaling. The data exhibit a steep rise of {theta}{sub flow} to a maximum at around 250 - 400 A MeV, followed by a moderate decrease as the bombarding energy increases further.

  17. Antiproton Induced Fission and Fragmentation of Nuclei

    CERN Multimedia

    2002-01-01

    The annihilation of slow antiprotons with nuclei results in a large highly localized energy deposition primarily on the nuclear surface. \\\\ \\\\ The study of antiproton induced fission and fragmentation processes is expected to yield new information on special nuclear matter states, unexplored fission modes, multifragmentation of nuclei, and intranuclear cascades.\\\\ \\\\ In order to investigate the antiproton-nucleus interaction and the processes following the antiproton annihilation at the nucleus, we propose the following experiments: \\item A)~Measurement of several fragments from fission and from multifragmentation in coincidence with particle spectra, especially neutrons and kaons. \\item B)~Precise spectra of $\\pi$, K, n, p, d and t with time-of-flight techniques. \\item C)~Installation of the Berlin 4$\\pi$ neutron detector with a 4$\\pi$ Si detector placed inside for fragments and charged particles. This yields neutron multiplicity distributions and consequently distributions of thermal excitation energies and...

  18. Fragmentation of methane molecules by antiproton impact

    Science.gov (United States)

    Salehzadeh, Arash; Kirchner, Tom

    2016-09-01

    Extending previous work for proton impact, we have investigated the fragmentation of methane molecules due to collisions with antiprotons in the 25 keV to 5 MeV impact energy range. The multi-center nature of the problem is addressed by using a spectral representation of the molecular Hartree-Fock-level Hamiltonian and a single-center expansion of the initially populated molecular orbitals. The two-center basis generator method (TC-BGM) is used for orbital propagation. Electron-removal cross sections obtained from the TC-BGM solutions are complemented with a dynamical decay-route fragmentation model to calculate cross sections for the production of fragment ions. Good agreement with the available experimental data is observed for CH4+,CH3+,CH2+and CH+. Work supported by NSERC, Canada.

  19. Fragmentation of Kozai–Lidov Disks

    Science.gov (United States)

    Fu, Wen; Lubow, Stephen H.; Martin, Rebecca G.

    2017-02-01

    We analyze the gravitational instability (GI) of a locally isothermal inclined disk around one component of a binary system. Such a disk can undergo global Kozai–Lidov (KL) cycles if the initial disk tilt is above the critical KL angle (of about 40◦). During these cycles, an initially circular disk exchanges its inclination for eccentricity, and vice versa. Self-gravity may suppress the cycles under some circumstances. However, with hydrodynamic simulations that include self-gravity, we show that for a sufficiently high initial disk tilts and for certain disk masses, disks can undergo KL oscillations and fragment due to GI, even when the Toomre Q value for an equivalent undisturbed disk is well within the stable regime (Q> 2). We suggest that KL triggered disk fragmentation provides a mechanism for the efficient formation of giant planets in binary systems and may enhance the fragmentation of disks in massive black hole binaries.

  20. Current status and future needs in diagnostics and vaccines for high pathogenicity avian influenza

    Science.gov (United States)

    Since 1959, 31 epizootics of high pathogenicity avian influenza (HPAI) have occurred in birds. Rapid detection and accurate identification of HPAI has been critical to controlling such epizootics in poultry. Specific paradigms for the detection and diagnosis of avian influenza virus (AIV) in poultry...

  1. Diffferential innate responses of chickens and ducks to low pathogenic avian influenza virus

    NARCIS (Netherlands)

    Cornelissen, J.B.W.J.; Post, J.; Peeters, B.P.H.; Vervelde, L.; Rebel, J.M.J.

    2012-01-01

    Ducks and chickens are hosts of avian influenza virus, each with distinctive responses to infection. To understand these differences, we characterized the innate immune response to low pathogenicity avian influenza virus H7N1 infection in chickens and ducks. Viral RNA was detected in the lungs of ch

  2. Rational design of avian metapneumovirus live attenuated vaccines by inhibiting viral messenger RNA cap methyltransferase

    Science.gov (United States)

    Avian metapneumovirus (aMPV), also known as avian pneumovirus or turkey rhinotracheitis, is a non-segmented negative-sense RNA virus belonging to the family of Paramyxoviridae, the subfamily Pneumovirinae, and the genus Metapneumovirus. aMPV is the causative agent of respiratory tract infection and ...

  3. Modelling the Innate Immune Response against Avian Influenza Virus in Chicken

    NARCIS (Netherlands)

    Hagenaars, T J; Fischer, E A J; Jansen, C A; Rebel, J M J; Spekreijse, D; Vervelde, L; Backer, J A; de Jong, M C M; Koets, A P

    2016-01-01

    At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load, interferon-α, -β

  4. Modelling the innate immune response against avian influenza virus in chicken

    NARCIS (Netherlands)

    Hagenaars, T.J.; Fischer, E.A.J.; Jansen, C.A.; Rebel, J.M.J.; Spekreijse, D.; Vervelde, L.; Backer, J.A.; Jong, de M.C.M.; Koets, A.P.

    2016-01-01

    At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load, interferon-α,

  5. Human Infection with Avian Influenza A(H7N9) Virus - China

    Science.gov (United States)

    ... Biorisk reduction Human infection with avian influenza A(H7N9) virus – China Disease outbreak news 18 January 2017 ... laboratory-confirmed human infection with avian influenza A(H7N9) virus and on 12 January 2017, the Health ...

  6. Phylogenetics and pathogenesis of early avian influenza viruses (H5N2), Nigeria

    Science.gov (United States)

    Prior to the first officially recognized outbreaks of highly pathogenic avian influenza (HPAI) in poultry in Nigeria, in February 2006, an effort based at the poultry diagnostic clinic of the University of Ibadan Veterinary Teaching Hospital, was underway to isolate avian influenza viruses from sick...

  7. Susceptibility of swine to H5 and H7 low pathogenic avian influenza viruses

    Science.gov (United States)

    The ability of pigs to become infected with low pathogenic avian influenza (LPAI) viruses from an avian reservoir, and then generate mammalian adaptable influenza A viruses (IAVs) is difficult to determine. Yet, it is an important link to understanding any relationship between LPAI virus ecology and...

  8. Chicken dendritic cells are susceptible to highly pathogenic avian influenza viruses which induce strong cytokine responses

    NARCIS (Netherlands)

    Vervelde, L.; Reemens, S.S.; Haarlem, van D.A.; Post, J.; Claassen, E.A.W.; Rebel, J.M.J.; Jansen, C.A.

    2013-01-01

    Infection with highly pathogenic avian influenza (HPAI) in birds and mammals is associated with severe pathology and increased mortality. We hypothesize that in contrast to low pathogenicity avian influenza (LPAI) infection, HPAI infection of chicken dendritic cells (DC) induces a cytokine deregulat

  9. Comparative susceptibility of waterfowl and gulls to highly pathogenic avian influenza H5N1 virus

    Science.gov (United States)

    Wild avian species in the Orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shorebirds) have traditionally been considered the natural reservoirs for avian influenza viruses (AIV) and morbidity or mortality is rarely associated with AIV infection in these hosts. However, ...

  10. Pathogenesis of avian influenza A (H5N1) viruses in pigs

    Science.gov (United States)

    Background. Genetic reassortment of avian influenza H5N1 viruses with currently circulating human influenza A strains is one possibility that could lead to efficient human-to-human transmissibility. Domestic pigs which are susceptible to infection with both human and avian influenza A viruses are o...

  11. Current developments in avian influenza vaccines, including safety of vaccinated birds as food.

    Science.gov (United States)

    Swayne, D E; Suarez, D L

    2007-01-01

    Until recently, most vaccines against avian influenza were based on oil-emulsified inactivated low- or high-pathogenicity viruses. Now, recombinant fowl pox and avian paramyxovirus type 1 vaccines with avian influenza H5 gene inserts (+ or - N1 gene insert) are available and licensed. New technologies might overcome existing limitations to make available vaccines that can be grown in tissue culture systems for more rapid production; provide optimized protection, as a result of closer genetic relations to field viruses; allow mass administration by aerosol, in drinking-water or in ovo; and allow easier strategies for identifying infected birds within vaccinated populations (DIVA). The technologies include avian influenza viruses with partial gene deletions, avian influenza-Newcastle disease virus chimeras, vectored vaccines such as adenoviruses and Marek's disease virus, and subunit vaccines. These new methods should be licensed only after their purity, safety, efficacy and potency against avian influenza viruses have been demonstrated, and, for live vectored vaccines, restriction of viral transmission to unvaccinated birds. Use of vaccines in countries affected by highly pathogenic avian influenza will not only protect poultry but will provide additional safety for consumers. Experimental studies have shown that birds vaccinated against avian influenza have no virus in meat and minimal amounts in eggs after HPAI virus challenge, and that replication and shedding from their respiratory and alimentary tracts is greatly reduced.

  12. Infection of children with avian-human reassortant influenza virus from pigs in Europe

    NARCIS (Netherlands)

    E.C.J. Claas (Eric); Y. Kawaoka (Yoshihiro); J.C. de Jong (Jan); N. Masurel (Nic); R.G. Webster (Robert)

    1994-01-01

    textabstractPigs have been proposed to act as the intermediate hosts in the generation of pandemic human influenza strains by reassortment of genes from avian and human influenza virus strains. The circulation of avian-like H1N1 influenza viruses in European pigs since 1979 and the detection of huma

  13. Risk Perceptions for Avian Influenza Virus Infection among Poultry Workers, China

    OpenAIRE

    Yu, Qi; Liu, Linqing; Pu, Juan; Zhao, Jingyi; Sun, Yipeng; Shen, Guangnian; Wei, Haitao; Zhu, Junjie; Zheng, Ruifeng; Xiong, Dongyan; Liu, Xiaodong; Liu, Jinhua

    2013-01-01

    To determine risk for avian influenza virus infection, we conducted serologic surveillance for H5 and H9 subtypes among poultry workers in Beijing, China, 2009–2010, and assessed workers’ understanding of avian influenza. We found that poultry workers had considerable risk for infection with H9 subtypes. Increasing their knowledge could prevent future infections.

  14. Personal Protective Equipment and Risk for Avian Influenza (H7N3)

    OpenAIRE

    Morgan, Oliver; Kuhne, Mirjam; Nair, Pat; Verlander, Neville Q.; Preece, Richard; McDougal, Marianne; Zambon, Maria; Reacher, Mark

    2009-01-01

    An outbreak of avian influenza (H7N3) among poultry resulted in laboratory-confirmed disease in 1 of 103 exposed persons. Incomplete use of personal protective equipment (PPE) was associated with conjunctivitis and influenza-like symptoms. Rigorous use of PPE by persons managing avian influenza outbreaks may reduce exposure to potentially hazardous infected poultry materials.

  15. Evolutionary Analysis of Inter-Farm Transmission Dynamics in a Highly Pathogenic Avian Influenza Epidemic

    NARCIS (Netherlands)

    Bataille, A.; Meer, van der F.; Stegeman, A.; Koch, G.

    2011-01-01

    Phylogenetic studies have largely contributed to better understand the emergence, spread and evolution of highly pathogenic avian influenza during epidemics, but sampling of genetic data has never been detailed enough to allow mapping of the spatiotemporal spread of avian influenza viruses during a

  16. Improved Empirical Parametrization of Fragmentation Cross Sections

    CERN Document Server

    Sümmerer, Klaus

    2012-01-01

    A new version is proposed for the universal empirical formula, EPAX, which describes fragmentation cross sections in high-energy heavy-ion reactions. The new version, EPAX 3, can be shown to yield cross sections that are in better agreement with experimental data for the most neutron-rich fragments than the previous version. At the same time, the very good agreement of EPAX 2 with data on the neutron-deficient side has been largely maintained. Comparison with measured cross sections show that the bulk of the data is reproduced within a factor of about 2, for cross sections down to the pico-barn range.

  17. Computer Model Of Fragmentation Of Atomic Nuclei

    Science.gov (United States)

    Wilson, John W.; Townsend, Lawrence W.; Tripathi, Ram K.; Norbury, John W.; KHAN FERDOUS; Badavi, Francis F.

    1995-01-01

    High Charge and Energy Semiempirical Nuclear Fragmentation Model (HZEFRG1) computer program developed to be computationally efficient, user-friendly, physics-based program for generating data bases on fragmentation of atomic nuclei. Data bases generated used in calculations pertaining to such radiation-transport applications as shielding against radiation in outer space, radiation dosimetry in outer space, cancer therapy in laboratories with beams of heavy ions, and simulation studies for designing detectors for experiments in nuclear physics. Provides cross sections for production of individual elements and isotopes in breakups of high-energy heavy ions by combined nuclear and Coulomb fields of interacting nuclei. Written in ANSI FORTRAN 77.

  18. Angular Momentum Population in Projectile Fragmentation

    Science.gov (United States)

    Podolyák, Zs.; Gladnishki, K. A.; Gerl, J.; Hellström, M.; Kopatch, Y.; Mandal, S.; Górska, M.; Regan, P. H.; Wollersheim, H. J.; Schmidt, K.-H.; Gsi-Isomer Collaboration

    2004-02-01

    Isomeric states in neutron-deficient nuclei around A ≈190 have been identified following the projectile fragmentation of a relativistic energy 238U beam. The deduced isomeric ratios are compared with a model based on the abrasion-ablation description. The experimental isomeric ratios are lower by a factor of ≈2 than the calculated ones assuming the `sharp cutoff' approximation. The observation of the previously reported isomeric Iπ=43/2- state in 215Ra represents the current record for the highest discrete spin state observed following a projectile fragmentation reaction.

  19. Parton Propagation and Fragmentation in QCD Matter

    Energy Technology Data Exchange (ETDEWEB)

    Alberto Accardi, Francois Arleo, William Brooks, David D' Enterria, Valeria Muccifora

    2009-12-01

    We review recent progress in the study of parton propagation, interaction and fragmentation in both cold and hot strongly interacting matter. Experimental highlights on high-energy hadron production in deep inelastic lepton-nucleus scattering, proton-nucleus and heavy-ion collisions, as well as Drell-Yan processes in hadron-nucleus collisions are presented. The existing theoretical frameworks for describing the in-medium interaction of energetic partons and the space-time evolution of their fragmentation into hadrons are discussed and confronted to experimental data. We conclude with a list of theoretical and experimental open issues, and a brief description of future relevant experiments and facilities.

  20. Radio Frequency Fragment Separator at NSCL

    Science.gov (United States)

    Bazin, D.; Andreev, V.; Becerril, A.; Doléans, M.; Mantica, P. F.; Ottarson, J.; Schatz, H.; Stoker, J. B.; Vincent, J.

    2009-07-01

    A new device has been designed and built at NSCL which provides additional filtering of radioactive beams produced via projectile fragmentation. The Radio Frequency Fragment Separator (RFFS) uses the time micro structure of the beams accelerated by the cyclotrons to deflect particles according to their time-of-flight, in effect producing a phase filtering. The transverse RF (Radio Frequency) electric field of the RFFS has superior filtering performance compared to other electrostatic devices, such as Wien filters. Such filtering is critical for radioactive beams produced on the neutron-deficient side of the valley of stability, where strong contamination occurs at intermediate energies from 50 to 200 MeV/u.

  1. Limit theorems for fragmentation processes with immigration

    CERN Document Server

    Knobloch, Robert

    2012-01-01

    In this paper we extend two limit theorems which were recently obtained for fragmentation processes to such processes with immigration. More precisely, in the setting with immigration we consider a limit theorem for the process counted with a random characteristic as well as the asymptotic behaviour of an empirical measure associated with the stopping line corresponding to the first blocks, in their respective line of descent, that are smaller than a given size. In addition, we determine the asymptotic decay rate of the size of the largest block in a homogeneous fragmentation process with immigration. The techniques used to proves these results are based on submartingale arguments.

  2. Radio Frequency Fragment Separator at NSCL

    Energy Technology Data Exchange (ETDEWEB)

    Bazin, D. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States)], E-mail: bazin@nscl.msu.edu; Andreev, V. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Becerril, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States); Doleans, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Mantica, P.F. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Ottarson, J. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Schatz, H. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States); Stoker, J.B. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States); Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Vincent, J. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824-1321 (United States)

    2009-07-21

    A new device has been designed and built at NSCL which provides additional filtering of radioactive beams produced via projectile fragmentation. The Radio Frequency Fragment Separator (RFFS) uses the time micro structure of the beams accelerated by the cyclotrons to deflect particles according to their time-of-flight, in effect producing a phase filtering. The transverse RF (Radio Frequency) electric field of the RFFS has superior filtering performance compared to other electrostatic devices, such as Wien filters. Such filtering is critical for radioactive beams produced on the neutron-deficient side of the valley of stability, where strong contamination occurs at intermediate energies from 50 to 200 MeV/u.

  3. Parton-to-Pion Fragmentation Reloaded

    CERN Document Server

    de Florian, D; Epele, M; Hernandez-Pinto, R J; Stratmann, M

    2014-01-01

    We present a new, comprehensive global analysis of parton-to-pion fragmentation functions at next-to-leading order accuracy in QCD. The obtained results are based on the latest experimental information on single-inclusive pion production in electron-positron annihilation, lepton-nucleon deep-inelastic scattering, and proton-proton collisions. An excellent description of all data sets is achieved, and the remaining uncertainties in parton-to-pion fragmentation functions are estimated based on the Hessian method. Extensive comparisons to the results from our previous global analysis are performed.

  4. Eigenmodes of decay and discrete fragmentation processes

    CERN Document Server

    Giraud, B G; Giraud, B G; Peschanski, R

    1994-01-01

    Linear rate equations are used to describe the cascading decay of an initial heavy cluster into fragments. This representation is based upon a triangular matrix of transition rates. We expand the state vector of mass multiplicities, which describes the process, into the biorthonormal basis of eigenmodes provided by the triangular matrix. When the transition rates have a scaling property in terms of mass ratios at binary fragmentation vertices, we obtain solvable models with explicit mathematical properties for the eigenmodes. A suitable continuous limit provides an interpolation between the solvable models. It gives a general relationship between the decay products and the elementary transition rates.

  5. Dissipative fragmentation in a phase space approach

    Energy Technology Data Exchange (ETDEWEB)

    Adorno, A.; Di Toro, M.; Bonasera, A.; Gregoire, C.; Gulminelli, F.

    Semi-classical approaches have evidenced the role of one and two-body dissipation in nucleus-nucleus collisions. On the other hand, a substantial energy dissipation and some angular momentum transfer have been observed at moderate energy where a fragmentation process is the dominant reaction mechanism. In order to analyse main features of these reactions, we developed a phenomenological model taking into account phase space constraints. The transition between deep inelastic collisions and abrasion-like fragmentation is described and a general agreement with available data is found.

  6. Growth patterns in brooding dinosaurs reveals the timing of sexual maturity in non-avian dinosaurs and genesis of the avian condition.

    Science.gov (United States)

    Erickson, Gregory M; Curry Rogers, Kristina; Varricchio, David J; Norell, Mark A; Xu, Xing

    2007-10-22

    The timing of sexual maturation in non-avian dinosaurs is not known. In extant squamates and crocodilians it occurs in conjunction with the initial slowing of growth rates as adult size is approached. In birds (living dinosaurs) on the other hand, reproductive activity begins well after somatic maturity. Here we used growth line counts and spacing in all of the known brooding non-avian dinosaurs to determine the stages of development when they perished. It was revealed that sexual maturation occurred well before full adult size was reached-the primitive reptilian condition. In this sense, the life history and physiology of non-avian dinosaurs was not like that of modern birds. Palaeobiological ramifications of these findings include the potential to deduce reproductive lifespan, fecundity and reproductive population sizes in non-avian dinosaurs, as well as aid in the identification of secondary sexual characteristics.

  7. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    WANG HongLiang; JIANG ChengYu

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly patho-genic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effec-tive therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  8. Experimental quantum simulation of Avian Compass in a nuclear magnetic resonance system

    Science.gov (United States)

    Pearson, Jason; Feng, GuanRu; Zheng, Chao; Long, GuiLu

    2016-12-01

    Avian magnetoreception is the capacity for avians to sense the direction of the Earth's magnetic field. Discovered more than forty years ago, it has attracted intensive studies over the years. One promising model for describing this capacity in avians is the widely used reference-and-probe model where radical pairs within the eyes of bird combines to form singlet and triplet quantum states. The yield depends on the angle between the Earth's magnetic field and the molecules' axis, hence the relative value of yield of the singlet state or triplet state enables avians to sense the direction. Here we report the experimental demonstration of avian magnetoreception in a nuclear magnetic resonance quantum information processor. It is shown clearly from the experiment that the yield of the singlet state attains maximum when it is normal to the Earth's magnetic field, and the experimental results agree with theory very well.

  9. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly pathogenic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effective therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  10. Surveillance of avian influenza viruses in Papua New Guinean poultry, June 2011 to April 2012.

    Science.gov (United States)

    Jonduo, Marinjho; Wong, Sook-San; Kapo, Nime; Ominipi, Paskalis; Abdad, Mohammad; Siba, Peter; McKenzie, Pamela; Webby, Richard; Horwood, Paul

    2013-01-01

    We investigated the circulation of avian influenza viruses in poultry populations throughout Papua New Guinea to assess the risk to the poultry industry and human health. Oropharyngeal swabs, cloacal swabs and serum were collected from 537 poultry from 14 provinces of Papua New Guinea over an 11-month period (June 2011 through April 2012). Virological and serological investigations were undertaken to determine the prevalence of avian influenza viruses. Neither influenza A viruses nor antibodies were detected in any of the samples. This study demonstrated that avian influenza viruses were not circulating at detectable levels in poultry populations in Papua New Guinea during the sampling period. However, avian influenza remains a significant risk to Papua New Guinea due to the close proximity of countries having previously reported highly pathogenic avian influenza viruses and the low biosecurity precautions associated with the rearing of most poultry populations in the country.

  11. Estimating the Effects of Habitat and Biological Interactions in an Avian Community.

    Directory of Open Access Journals (Sweden)

    Robert M Dorazio

    Full Text Available We used repeated sightings of individual birds encountered in community-level surveys to investigate the relative roles of habitat and biological interactions in determining the distribution and abundance of each species. To analyze these data, we developed a multispecies N-mixture model that allowed estimation of both positive and negative correlations between abundances of different species while also estimating the effects of habitat and the effects of errors in detection of each species. Using a combination of single- and multispecies N-mixture modeling, we examined for each species whether our measures of habitat were sufficient to account for the variation in encounter histories of individual birds or whether other habitat variables or interactions with other species needed to be considered. In the community that we studied, habitat appeared to be more influential than biological interactions in determining the distribution and abundance of most avian species. Our results lend support to the hypothesis that abundances of forest specialists are negatively affected by forest fragmentation. Our results also suggest that many species were associated with particular types of vegetation as measured by structural attributes of the forests. The abundances of 6 of the 73 species observed in our study were strongly correlated. These species included large birds (American Crow (Corvus brachyrhynchos and Red-winged Blackbird (Agelaius phoeniceus that forage on the ground in open habitats and small birds (Red-eyed Vireo (Vireo olivaceus, House Wren (Troglodytes aedon, Hooded Warbler (Setophaga citrina, and Prairie Warbler (Setophaga discolor that are associated with dense shrub cover. Species abundances were positively correlated within each size group and negatively correlated between groups. Except for the American Crow, which preys on eggs and nestlings of small song birds, none of the other 5 species is known to display direct interactions, so we

  12. [A(H5N1) and A(H7N9) avian influenza: the H7N9 avian influenza outbreak of 2013].

    Science.gov (United States)

    Wang, Quan; Yao, Kai-Hu

    2013-06-01

    influenza virus can infect humans and cause disease. The clinical presentation of human infection is usually mild, but the infection caused by A(H5N1) avian influenza virus occurring initially in Hongkong in 1997 or the A(H7N9) virus isolated first at the beginning of this year in China is severe and characterized by high mortality. The mortality rate of adolescents and children caused by H5N1 avian influenza is lower than that of adults and the younger the child the lower the mortality rate. A few pediatric H7N9 avian influenza cases recovered soon after treatment. A child was determined to be a H7N9 avian influenza virus carrier. These findings suggested that the pediatric H7N9 avian influenza infection was mild. It is very important to start anti-virus treatment with oseltamivir as early as possible in cases of avian influenza infection is considered. Combined therapy, including respiratory and circulatory support and inhibiting immunological reaction, is emphasized in the treatment of severe cases.

  13. The relationship between sperm viability and DNA fragmentation rates

    OpenAIRE

    Mary K. Samplaski; Dimitromanolakis, Apostolos; Lo, Kirk C; Grober, Ethan D.; Mullen, Brendan; Garbens, Alaina; Jarvi, Keith A

    2015-01-01

    Background In humans, sperm DNA fragmentation rates have been correlated with sperm viability rates. Reduced sperm viability is associated with high sperm DNA fragmentation, while conversely high sperm viability is associated with low rates of sperm DNA fragmentation. Both elevated DNA fragmentation rates and poor viability are correlated with impaired male fertility, with a DNA fragmentation rate of > 30% indicating subfertility. We postulated that in some men, the sperm viability assay coul...

  14. VARIATION OF NON-CODING REGION AND CODING REGION OF 5’-TERMINAL CRNA OF POLYMERASE BASIC 1 OF AVIAN INFLUENZA VIRUS SUBTYPE H5N1

    Directory of Open Access Journals (Sweden)

    Gusti Ayu Yuniati Kencana

    2009-03-01

    Full Text Available The sequence of the Non-Coding Region (NCR and Coding Region (CR of 5’-terminal cRNA of thepolymerase basic 1 (PB1 gene as a major factor for the species adaptation of avian influenza virussubtype H5N1 (AIV H5N1 has been analysed. The information could be a virological signal for theemergence of a new strain with pandemic potential. Total RNA from twenty six (26 avian influenzasubtype H5N1 isolates were amplified using reverse-transcriptase-polymerase chain reaction (RT-PCRwith a universal forward primer for influenza virus and specifically designed backward primers. Fifteen(15 PB1 gene fragments could be amplified. RT-PCR products were sequenced and analyzed using Mega4software. The length of NCR of PB1 gene was found to be 24 bases and mostly shows conserved sequence,with an exception of Dk/Badung/2006 isolate which has C-7T substitution. A/T composition of PB1 NCRwas 54,2%, while the Dk/Badung/2006 isolate was 58,3%. Species and geographical specificity could not befound in the genetic distance, the amino acid polymorphism, as well as the phylogenetic analysis of t

  15. Avian Influenza: a global threat needing a global solution

    Directory of Open Access Journals (Sweden)

    Koh GCH

    2008-11-01

    Full Text Available Abstract There have been three influenza pandemics since the 1900s, of which the 1919–1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI is endemic in Asia as a result of unregulated poultry rearing in rural areas. Such birds often live in close proximity to humans and this increases the chance of genetic re-assortment between avian and human influenza viruses which may produce a mutant strain that is easily transmitted between humans. Once this happens, a global pandemic is likely. Unlike SARS, a person with influenza infection is contagious before the onset of case-defining symptoms which limits the effectiveness of case isolation as a control strategy. Researchers have shown that carefully orchestrated of public health measures could potentially limit the spread of an AI pandemic if implemented soon after the first cases appear. To successfully contain and control an AI pandemic, both national and global strategies are needed. National strategies include source surveillance and control, adequate stockpiles of anti-viral agents, timely production of flu vaccines and healthcare system readiness. Global strategies such as early integrated response, curbing the disease outbreak at source, utilization of global resources, continuing research and open communication are also critical.

  16. Risky Zoographies: The Limits of Place in Avian Flu Management

    Directory of Open Access Journals (Sweden)

    Natalie Porter

    2012-11-01

    Full Text Available Global anxieties about avian influenza stem from a growing recognition that highly-virulent, highly-mobile disease vectors infiltrate human spaces in ways that are difficult to perceive, and even more difficult to manage. This article analyses a participatory health intervention in Việt Nam to explore how avian influenza threats challenge long-held understandings of animals’ place in the environment and society. In this intervention, poultry farmers collaborated with health workers to illustrate maps of avian flu risks in their communities. Participant-observation of the risk-mapping exercises shows that health workers treated poultry as commodities, and located these animals in environments that could be transformed and dominated by humans. However, these maps did not sufficiently represent the physical and social landscapes where humans and poultry coexist in Việt Nam. As such, farmers located poultry in environments dominated by risky nonhuman forces such as winds, waterways, and other organisms. I argue that these divergent risk maps demonstrate how ecological factors, interpersonal networks, and global market dynamics combine to engender a variety of interspecies relationships, which in turn shape the location of disease risks in space. I develop the term risky zoographies to signal the emergence of competing descriptions of animals and their habitats in zoonotic disease contexts. This concept suggests that as wild animals, livestock products, and microbial pathogens continue to globalise, place-based health interventions that limit animals to particular locales are proving inadequate. Risky zoographies signal the inextricability of nonhuman animals from human spaces, and reveal interspecies interactions that transect and transcend environments.

  17. Antimicrobial resistance of bacterial strains isolated from avian cellulitis

    Directory of Open Access Journals (Sweden)

    MM Santos

    2014-03-01

    Full Text Available Avian cellulitis is an inflammatory process in the subcutaneous tissue, mainly located in the abdomen and thighs. This problem is commonly observed in poultry at slaughter and it is considered one of the major causes of condemnation of carcasses in Brazil. The aim of this study was to perform the microbial isolation of lesions of avian cellulitis from a processing plant located in the State of Goiás in order to analyze antimicrobial resistance by antibiogram test and to detect resistance genes by polymerase chain reaction. A total of 25 samples of avian cellulitis lesions were analyzed, from which 30 bacterial strains were isolated. There were eleven (44% strains of Escherichia coli, nine (36% strains of Staphylococcus epidermidis, seven (28% strains of Proteus mirabilis and three (12% strains of Manheimiahaemolytica. The antibiogram test showed that all strains were resistant to at least one antimicrobial. The gene of antimicrobial resistance tetB was detected in E. coli, S. epidermidis and P. mirabilis strains, and was the most frequently observed gene. The gene of antimicrobial resistance Sul1 was detected in all bacterial species, while tetA was found in E. coli and S. epidermidis strains, SHV in E. coli strains, S. epidermidis and P. mirabilis,and cat1 in one P. mirabilis strain. The results suggest a potential public health hazard due to the ability of these microorganisms to transmit antimicrobial resistancegenes to other microorganisms present in the intestinal tract of humans and animals, which may affect clinical-medical usage of these drugs.

  18. MicroRNA expression profiles in avian haemopoietic cells

    Directory of Open Access Journals (Sweden)

    Yongxiu eYao

    2013-08-01

    Full Text Available MicroRNAs (miRNAs are small, abundant, non-coding RNAs that modulate gene expression by interfering with translation or stability of mRNA transcripts in a sequence-specific manner. A total of 734 precursor and 996 mature miRNAs have so far been identified in the chicken genome. A number of these miRNAs are expressed in a cell type-specific manner, and understanding their function requires detailed examination of their expression in different cell types. We carried out deep sequencing of small RNA populations isolated from stimulated or transformed avian haemopoietic cell lines to determine the changes in the expression profiles of these important regulatory molecules during these biological events. There were significant changes in the expression of a number of miRNAs, including miR-155, in chicken B cells stimulated with CD40 ligand. Similarly, avian leukosis virus (ALV-transformed DT40 cells also showed changes in miRNA expression in relation to the naïve cells. Embryonic stem cell line BP25 demonstrated a distinct cluster of upregulated miRNAs, many of which were shown previously to be involved in embryonic stem cell development. Finally, chicken macrophage cell line HD11 showed changes in miRNA profiles, some of which are thought to be related to the transformation by v-myc transduced by the virus. This work represents the first publication of a catalog of microRNA expression in a range of important avian cells and provides insights into the potential roles of miRNAs in the hematopoietic lineages of cells in a model non-mammalian species.

  19. Oscillating Filaments. I. Oscillation and Geometrical Fragmentation

    Science.gov (United States)

    Gritschneder, Matthias; Heigl, Stefan; Burkert, Andreas

    2017-01-01

    We study the stability of filaments in equilibrium between gravity and internal as well as external pressure using the grid-based AMR code RAMSES. A homogeneous, straight cylinder below a critical line mass is marginally stable. However, if the cylinder is bent, such as with a slight sinusoidal perturbation, an otherwise stable configuration starts to oscillate, is triggered into fragmentation, and collapses. This previously unstudied behavior allows a filament to fragment at any given scale, as long as it has slight bends. We call this process “geometrical fragmentation.” In our realization, the spacing between the cores matches the wavelength of the sinusoidal perturbation, whereas up to now, filaments were thought to be only fragmenting on the characteristic scale set by the mass-to-line ratio. Using first principles, we derive the oscillation period as well as the collapse timescale analytically. To enable a direct comparison with observations, we study the line-of-sight velocity for different inclinations. We show that the overall oscillation pattern can hide the infall signature of cores.

  20. Distribution and Causes of Global Forest Fragmentation

    Directory of Open Access Journals (Sweden)

    K. Bruce Jones

    2003-12-01

    Full Text Available Because human land uses tend to expand over time, forests that share a high proportion of their borders with anthropogenic uses are at higher risk of further degradation than forests that share a high proportion of their borders with non-forest, natural land cover (e.g., wetland. Using 1-km advanced very high resolution radiometer (AVHRR satellite-based land cover, we present a method to separate forest fragmentation into natural and anthropogenic components, and report results for all inhabited continents summarized by World Wildlife Fund biomes. Globally, over half of the temperate broadleaf and mixed forest biome and nearly one quarter of the tropical rainforest biome have been fragmented or removed by humans, as opposed to only 4% of the boreal forest. Overall, Europe had the most human-caused fragmentation and South America the least. This method may allow for improved risk assessments and better targeting for protection and remediation by identifying areas with high amounts of human-caused fragmentation.

  1. Element Distribution and Multiplicity of Heavy Fragments

    CERN Multimedia

    2002-01-01

    This experiment will measure the energy and angular distribution of heavy fragments produced in the reactions of |1|2C on several targets between |2|7Al and |2|3|8U at 86~MeV/u. The systematic investigation of a highly excited interaction region (fireball) by means of a clean N and Z identification of heavy tar fragments, may result in a better understanding of temperature concept and of the degree of equilibration of the local interaction region with respect to the total system. For this investigation a large-area position sensitive ionization chamber of 50~msr solid angle in conjunction with a time-of-flight telescope consisting of parallel-plate detectors will be used. \\\\ \\\\ In order to get information on the transverse momentum transfer and the inelasticity of the collision, the energy of the PROJECTILE-FRAGMENTS will be measured at forward angles with a plastic scintillator hodoscope. In addition to this inclusive measurement correlations between heavy fragments will be investigated by means of three pos...

  2. Metagenome Fragment Classification Using -Mer Frequency Profiles

    Directory of Open Access Journals (Sweden)

    Gail Rosen

    2008-01-01

    Full Text Available A vast amount of microbial sequencing data is being generated through large-scale projects in ecology, agriculture, and human health. Efficient high-throughput methods are needed to analyze the mass amounts of metagenomic data, all DNA present in an environmental sample. A major obstacle in metagenomics is the inability to obtain accuracy using technology that yields short reads. We construct the unique -mer frequency profiles of 635 microbial genomes publicly available as of February 2008. These profiles are used to train a naive Bayes classifier (NBC that can be used to identify the genome of any fragment. We show that our method is comparable to BLAST for small 25 bp fragments but does not have the ambiguity of BLAST's tied top scores. We demonstrate that this approach is scalable to identify any fragment from hundreds of genomes. It also performs quite well at the strain, species, and genera levels and achieves strain resolution despite classifying ubiquitous genomic fragments (gene and nongene regions. Cross-validation analysis demonstrates that species-accuracy achieves 90% for highly-represented species containing an average of 8 strains. We demonstrate that such a tool can be used on the Sargasso Sea dataset, and our analysis shows that NBC can be further enhanced.

  3. Modelling of the PELE fragmentation dynamics

    NARCIS (Netherlands)

    Verreault, J.

    2014-01-01

    The Penetrator with Enhanced Lateral Effect (PELE) is a type of explosive-free projectile that undergoes radial fragmentation upon an impact with a target plate. This type of projectile is composed of a brittle cylindrical shell (the jacket) filled in its core with a material characterized with a la

  4. Inclusion: The Unifying Thread for Fragmented Metaphors

    Science.gov (United States)

    Doyle, Lynn H.

    2004-01-01

    The fabric of educational leadership is changing. Murphy (2001) has suggested three new metaphors for educational leaders: moral stewards, builders of communities, and educators for school improvement. However, shifting priorities and contradictions between these metaphors could result in fragmentation within the field. This article discusses…

  5. Water cluster fragmentation probed by pickup experiments

    Science.gov (United States)

    Huang, Chuanfu; Kresin, Vitaly V.; Pysanenko, Andriy; Fárník, Michal

    2016-09-01

    Electron ionization is a common tool for the mass spectrometry of atomic and molecular clusters. Any cluster can be ionized efficiently by sufficiently energetic electrons, but concomitant fragmentation can seriously obstruct the goal of size-resolved detection. We present a new general method to assess the original neutral population of the cluster beam. Clusters undergo a sticking collision with a molecule from a crossed beam, and the velocities of neat and doped cluster ion peaks are measured and compared. By making use of longitudinal momentum conservation, one can reconstruct the sizes of the neutral precursors. Here this method is applied to H2O and D2O clusters in the detected ion size range of 3-10. It is found that water clusters do fragment significantly upon electron impact: the deduced neutral precursor size is ˜3-5 times larger than the observed cluster ions. This conclusion agrees with beam size characterization by another experimental technique: photoionization after Na-doping. Abundant post-ionization fragmentation of water clusters must therefore be an important factor in the interpretation of experimental data; interestingly, there is at present no detailed microscopic understanding of the underlying fragmentation dynamics.

  6. Computations in Fragments of Intuitionistic Propositional Logic

    NARCIS (Netherlands)

    Jongh, Dick de; Hendriks, Lex; Renardel de Lavalette, Gerard R.

    1991-01-01

    This article is a report on research in progress into the structure of finite diagrams of intuitionistic propositional logic with the aid of automated reasoning systems for larger calculations. A fragment of a propositional logic is the set of formulae built up from a finite number of propositional

  7. DFT STUDIES OF DP-3 AMYLOSE FRAGMENTS

    Science.gov (United States)

    This study extends our work on mono- and disaccharides to structures with three glucose residues by two alpha-[1-4] bridges, denoted herein as DP-3's. DFT optimization studies of DP-3 fragments have been carried out at the B3LYP/6-311++G** level of theory. Different hydroxymethyl conformations (gg...

  8. Conformational studies of cellulosic fragments by DFT

    Science.gov (United States)

    The study of cellulosic fragments by DFTr is a continuation of our efforts to produce quality structural data that will be valuable to those working in the field of cellulose structure and enzymatic degradation. Using a reduced basis set and density functional DFTr (B3LYP), optimization of cellulosi...

  9. Brownian shape motion: Fission fragment mass distributions

    Directory of Open Access Journals (Sweden)

    Sierk Arnold J.

    2012-02-01

    Full Text Available It was recently shown that remarkably accurate fission-fragment mass distributions can be obtained by treating the nuclear shape evolution as a Brownian walk on previously calculated five-dimensional potential-energy surfaces; the current status of this novel method is described here.

  10. Fragmentation of a Jet with Small Radius

    CERN Document Server

    Dai, Lin; Leibovich, Adam K

    2016-01-01

    In this paper we consider the fragmentation of a parton into a jet with small jet radius $R$. Perturbatively, logarithms of $R$ can appear, which for narrow jets can lead to large corrections. Using soft-collinear effective theory (SCET), we introduce the jet fragmentation function (JFF), which describes the fragmentation of a parton into a jet. We discuss how these objects are related to the standard jet functions. Calculating the JFF to next-to-leading order, we show that these objects satisfy the standard DGLAP evolution equations, with a natural scale that depends upon $R$. By using standard renormalization group evolution, we can therefore resum logarithms of $R$. We further use SCET to prove a factorization theorem where the JFFs naturally appear, for the fragmentation of a hadron within a jet with small $R$. Finally, we also show how this formalism can be used to resum the ratio of jet radii for a subjet to be emitted from within a fat jet.

  11. Searching Fragment Spaces with feature trees.

    Science.gov (United States)

    Lessel, Uta; Wellenzohn, Bernd; Lilienthal, Markus; Claussen, Holger

    2009-02-01

    Virtual combinatorial chemistry easily produces billions of compounds, for which conventional virtual screening cannot be performed even with the fastest methods available. An efficient solution for such a scenario is the generation of Fragment Spaces, which encode huge numbers of virtual compounds by their fragments/reagents and rules of how to combine them. Similarity-based searches can be performed in such spaces without ever fully enumerating all virtual products. Here we describe the generation of a huge Fragment Space encoding about 5 * 10(11) compounds based on established in-house synthesis protocols for combinatorial libraries, i.e., we encode practically evaluated combinatorial chemistry protocols in a machine readable form, rendering them accessible to in silico search methods. We show how such searches in this Fragment Space can be integrated as a first step in an overall workflow. It reduces the extremely huge number of virtual products by several orders of magnitude so that the resulting list of molecules becomes more manageable for further more elaborated and time-consuming analysis steps. Results of a case study are presented and discussed, which lead to some general conclusions for an efficient expansion of the chemical space to be screened in pharmaceutical companies.

  12. Fragmentation characteristics analysis of sandstone fragments based on impact rockburst test

    Institute of Scientific and Technical Information of China (English)

    Dongqiao Liu; Dejian Li; Fei Zhao; Chengchao Wang

    2014-01-01

    Impact rockburst test on sandstone samples with a central hole is carried out under true triaxial static loads and vertical dynamic load conditions, and rock fragments after the test are collected. The fragments of sandstone generated from strain rockburst test and uniaxial compression test are also collected. The fragments are weighed and the length, width and thickness of each piece of fragments are measured respectively. The fragment quantities with coarse, medium, fine and micro grains in different size ranges, mass and particles distributions are also analyzed. Then, the fractal dimension of fragments is calculated by the methods of size-frequency, mass-frequency and length-to-thickness ratio-frequency. It is found that the crushing degree of impact rockburst fragments is higher, accompanied with blocky character-istics observably. The mass percentage of small grains, including fine and micro grains, in impact rock-burst test is higher than those in strain rockburst test and uniaxial compression test. Energy dissipation from rockburst tests is more than that from uniaxial compression test, as the quantity of micro grains generated does.

  13. Avian radioecology on a nuclear power station site. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Levy, C.K.; Maletskos, C.J.; Youngstrom, K.A.

    1975-01-01

    A summary of a six-year avian radioecology study at the site of a nuclear power plant in Massachusetts is reported. A completed historical summary is followed by a description of mathematical models developed to calculate the effects on bird body burdens of various changes in environmental radionuclide levels. Examples are presented. Radionuclide metabolism studies in which acute doses of /sup 131/I and /sup 137/Cs were administered to four species of wild birds are presented. Radionuclides were administered both intravenously and orally; no apparent differences in uptake or elimination rates were observed between the two methods.

  14. USGS role and response to highly pathogenic avian influenza

    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

  15. Avian influenza biosecurity: a key for animal and human protection

    Directory of Open Access Journals (Sweden)

    Nikolas Charisis

    2008-12-01

    Full Text Available Modern biosecurity methods have provided the best way of preventing the spread of a communicable disease since people realised that human and animal contact can transmit exotic diseases. The avian influenza virus is readily transmitted through animal vectors and inanimate matter and incurs heavy losses to the poultry industry. Biosecurity measures include the prevention of vaccination of flocks in an endemic area and the isolation of farms from the surrounding world (villages, other farms, fields, etc.. Veterinary services work in liaison with owners to implement national quarantine and vaccination measures for the benefit of farmers and the industry and for protection of public health.

  16. Avian influenza a (H5N1): A preliminary review

    OpenAIRE

    Padhi S.; Panigrahi P; Mahapatra A; Mahapatra S

    2004-01-01

    Humanity has been at the receiving end of many viral diseases since ages. Sudden emergence and re-emergence of new viral diseases in human beings has surprised the medical scientists from time to time. "Avian influenza" or "Bird flu" by H5N1 epidemics is one such surprise. Although many aspects about this disease are clear, there are some dark areas regarding vaccine development that need to be further explored and understood, so as to effectively contain the spread of this disease. The prese...

  17. Avian influenza a (H5N1: A preliminary review

    Directory of Open Access Journals (Sweden)

    Padhi S

    2004-01-01

    Full Text Available Humanity has been at the receiving end of many viral diseases since ages. Sudden emergence and re-emergence of new viral diseases in human beings has surprised the medical scientists from time to time. "Avian influenza" or "Bird flu" by H5N1 epidemics is one such surprise. Although many aspects about this disease are clear, there are some dark areas regarding vaccine development that need to be further explored and understood, so as to effectively contain the spread of this disease. The present article details out almost everything known about this interesting disease along with the review of the recent literature.

  18. The Spectrum of Satellite Breakup and Fragmentation

    Science.gov (United States)

    Finkleman, D.

    The objective of this paper is to expose the spectrum of satellite breakup physics and is implications for debris production and observables. Satellite response to the debris environment generally emphasizes small scale hypervelocity impact or the interaction of intense, coherent radiation with satellite surfaces or internals. There are empirical correlations of fragment size distributions based on arena tests and extremely rare observations of breakups in space. Klinkrad describes well research on material response to hypervelocity impact such as the ballistic limit for various materials and shielding walls. Smirnov, et. al., report well the phenomenology of breakups under the influence of nonuniform internal loading of monolithic bodies, such as pressurized tanks. They set forth the transformation of elastic energy into fragment kinetic energy. They establish a sound physical framework for bounding the number of fragments. We took advantage of these works in our previous papers. There is not much research into the response of nonuniform structures to hypervelocity collisions with similarly massive and complex objects. This work generally employs complex hydrodynamic and finite element computation that is not well suited to real time, operational assessment of the consequences of such encounters. We hope to diminish the void between the extremes of microscopic impact and complex hydrocodes. Our previous reports employed the framework established by Chobotov and Spencer, fundamentally equilibrium, Newtonian approach. We now explore the spectrum of interactions and debris evolutions possible with realistic combinations of these theories. The spectrum encompasses Newtonian, semi-elastic energy and momentum transfer through little or no momentum exchange and from virtually all of the mass of the colliders being involved through fractional mass involvement. We observe that the more Newtonian outcomes do not agree well with sparse observations of the few collisions that

  19. A decadal view of magma fragmentation

    Science.gov (United States)

    Cashman, K. V.; Rust, A.

    2010-12-01

    Although the past decade has seen fundamental advances in studies of explosive volcanism, the disruption to air traffic caused by the 2010 eruption of Eyjafjallajökull, Iceland, highlights the need for improved understanding of magmatic fragmentation in general, and of fine ash generation in particular. To develop a theoretical basis for predicting the fine ash content of eruptive plumes, we need to understand not only fragmentation mechanisms but also the dependence of those mechanisms on conditions of magma ascent and degassing. Experimental and analytical approaches to this problem include experimental studies of vesiculation and permeability development in silicic melts, quantitative textural studies of pyroclasts to constrain conditions that reduce fragmentation efficiency (that is, allow vesicular clasts to be preserved), direct experiments on fragmentation in both natural and analog materials, and determination of total grain size distributions (TGSDs) of pyroclastic deposits. Experiments on silicic melts have demonstrated that very high supersaturations (overpressures ΔP) may be achieved in silicic melts prior to homogeneous bubble nucleation, and that the high bubble number densities of silicic pumice require not only homogeneous nucleation but also nucleation of a mixed H2O-CO2 gas phase. In most pumice and scoria clasts, resulting vesicle populations form power law size distributions; power law exponents >3 in silicic tephras indicate that small vesicles comprise most of the vesicle volume (consistent with rapid late-stage vesiculation at high ΔP), while exponents 60-70%) and show no dependence on either melt composition or mass eruption rate; this suggests that melt porosity is more important than either decompression rate or magma rheology for clast preservation. These pyroclasts also have uniformly high permeabilities, high pore connectivity, and simple porous pathways, all of which suggest that ease of gas escape also contributed to clast

  20. Public Health and Epidemiological Considerations For Avian Influenza Risk Mapping and Risk Assessment

    Directory of Open Access Journals (Sweden)

    Joseph P. Dudley

    2008-12-01

    Full Text Available Avian influenza viruses are now widely recognized as important threats to agricultural biosecurity and public health, and as the potential source for pandemic human influenza viruses. Human infections with avian influenza viruses have been reported from Asia (H5N1, H5N2, H9N2, Africa (H5N1, H10N7, Europe (H7N7, H7N3, H7N2, and North America (H7N3, H7N2, H11N9. Direct and indirect public health risks from avian influenzas are not restricted to the highly pathogenic H5N1 "bird flu" virus, and include low pathogenic as well as high pathogenic strains of other avian influenza virus subtypes, e.g., H1N1, H7N2, H7N3, H7N7, and H9N2. Research has shown that the 1918 Spanish Flu pandemic was caused by an H1N1 influenza virus of avian origins, and during the past decade, fatal human disease and human-to-human transmission has been confirmed among persons infected with H5N1 and H7N7 avian influenza viruses. Our ability to accurately assess and map the potential economic and public health risks associated with avian influenza outbreaks is currently constrained by uncertainties regarding key aspects of the ecology and epidemiology of avian influenza viruses in birds and humans, and the mechanisms by which highly pathogenic avian influenza viruses are transmitted between and among wild birds, domestic poultry, mammals, and humans. Key factors needing further investigation from a risk management perspective include identification of the driving forces behind the emergence and persistence of highly pathogenic avian influenza viruses within poultry populations, and a comprehensive understanding of the mechanisms regulating transmission of highly pathogenic avian influenza viruses between industrial poultry farms and backyard poultry flocks. More information is needed regarding the extent to which migratory bird populations to contribute to the transnational and transcontinental spread of highly pathogenic avian influenza viruses, and the potential for wild bird

  1. The role of the legal and illegal trade of live birds and avian products in the spread of avian influenza.

    Science.gov (United States)

    van den Berg, T

    2009-04-01

    The panzootic of the H5N1 strain of highly pathogenic avian influenza has become an international crisis. All parts of the world are now considered at risk due to trade globalisation, with the worldwide movement of animals, products and humans, and because of the possible spread of the virus through the migration of wild birds. The risk of introducing notifiable avian influenza (NAI) through trade depends on several factors, including the disease status of the exporting country and the type of products. The highest risk occurs in the trade of live birds. It is important to assess and manage these risks to ensure that global trade does not result in the dissemination of NAI. However, it is also important that the risk of infection is not used as an unjustified trade barrier. The role of the regulatory authorities is thus to facilitate the safe trade of animal products according to international guidelines. Nevertheless, the balance between acceptable risk and safe trade is difficult to achieve. Since the movements of poultry and birds are sometimes difficult to trace, the signature or 'identity card' of each isolated virus can be very informative. Indeed, sequencing the genes of H5N1 and other avian influenza viruses has assisted greatly in establishing links and highlighting differences between isolates from different countries and tracing the possible source of introduction. Recent examples from Asia, Europe and Africa, supported by H5N1 molecular fingerprinting, have demonstrated that the sources of introduction can be many and no route should be underestimated.

  2. C-Terminal Amino Acids 471-507 of Avian Hepatitis E Virus Capsid Protein Are Crucial for Binding to Avian and Human Cells.

    Science.gov (United States)

    Zhang, Xinquan; Bilic, Ivana; Marek, Ana; Glösmann, Martin; Hess, Michael

    2016-01-01

    The infection of chickens with avian Hepatitis E virus (avian HEV) can be asymptomatic or induces clinical signs characterized by increased mortality and decreased egg production in adult birds. Due to the lack of an efficient cell culture system for avian HEV, the interaction between virus and host cells is still barely understood. In this study, four truncated avian HEV capsid proteins (ORF2-1 - ORF2-4) with an identical 338aa deletion at the N-terminus and gradual deletions from 0, 42, 99 and 136aa at the C-terminus, respectively, were expressed and used to map the possible binding site within avian HEV capsid protein. Results from the binding assay showed that three truncated capsid proteins attached to avian LMH cells, but did not penetrate into cells. However, the shortest construct, ORF2-4, lost the capability of binding to cells suggesting that the presence of amino acids 471 to 507 of the capsid protein is crucial for the attachment. The construct ORF2-3 (aa339-507) was used to study the potential binding of avian HEV capsid protein to human and other avian species. It could be demonstrated that ORF2-3 was capable of binding to QT-35 cells from Japanese quail and human HepG2 cells but failed to bind to P815 cells. Additionally, chicken serum raised against ORF2-3 successfully blocked the binding to LMH cells. Treatment with heparin sodium salt or sodium chlorate significantly reduced binding of ORF2-3 to LMH cells. However, heparinase II treatment of LMH cells had no effect on binding of the ORF2-3 construct, suggesting a possible distinct attachment mechanism of avian as compared to human HEV. For the first time, interactions between avian HEV capsid protein and host cells were investigated demonstrating that aa471 to 507 of the capsid protein are needed to facilitate interaction with different kind of cells from different species.

  3. Spreading Of Avian Flu On Duck And Its Impact On Social Economy: Lesson Learnt From Avian Flu Cases On Chicken

    OpenAIRE

    Nyak Ilham

    2013-01-01

    Bird flu disease that attacks duck dismissed the notion of duck immune to bird flu disease. Learning from the experience of bird flu disease that attacks poultry in the year of 2004-2005, necessary to measure the spread of disease prevention bird flu in ducks. This paper aims to describe the business and trade patterns of duck associated with the spread of avian influenza and predict the socio-economic impact of bird flu on duck farms in Indonesia. Duck rearing patterns mostly are in the e...

  4. Avian evolution: from Darwin's finches to a new way of thinking about avian forebrain organization and behavioural capabilities.

    Science.gov (United States)

    Reiner, Anton

    2009-02-23

    The study of birds, especially the Galapagos finches, was important to Darwin in the development of the theory of evolution by natural selection. Birds have also been at the centre of a recent reformulation in understanding cerebral evolution and the substrates for higher cognition. While it was once thought that birds possess a simple cerebrum and were thus limited to instinctive behaviours, it is now clear that birds possess a well-developed cerebrum that looks very different from the mammalian cerebrum but can support a cognitive ability that for some avian species rivals that in primates.

  5. Electrochemical DNA Biosensor Based on a Tetrahedral Nanostructure Probe for the Detection of Avian Influenza A (H7N9) Virus.

    Science.gov (United States)

    Dong, Shibiao; Zhao, Rongtao; Zhu, Jiangong; Lu, Xiao; Li, Yang; Qiu, Shaofu; Jia, Leili; Jiao, Xiong; Song, Shiping; Fan, Chunhai; Hao, RongZhang; Song, HongBin

    2015-04-29

    A DNA tetrahedral nanostructure-based electrochemical biosensor was developed to detect avian influenza A (H7N9) virus through recognizing a fragment of the hemagglutinin gene sequence. The DNA tetrahedral probe was immobilized onto a gold electrode surface based on self-assembly between three thiolated nucleotide sequences and a longer nucleotide sequence containing complementary DNA to hybridize with the target single-stranded (ss)DNA. The captured target sequence was hybridized with a biotinylated-ssDNA oligonucleotide as a detection probe, and then avidin-horseradish peroxidase was introduced to produce an amperometric signal through the interaction with 3,3',5,5'-tetramethylbenzidine substrate. The target ssDNA was obtained by asymmetric polymerase chain reaction (PCR) of the cDNA template, reversely transcribed from the viral lysate of influenza A (H7N9) virus in throat swabs. The results showed that this electrochemical biosensor could specifically recognize the target DNA fragment of influenza A (H7N9) virus from other types of influenza viruses, such as influenza A (H1N1) and (H3N2) viruses, and even from single-base mismatches of oligonucleotides. Its detection limit could reach a magnitude of 100 fM for target nucleotide sequences. Moreover, the cycle number of the asymmetric PCR could be reduced below three with the electrochemical biosensor still distinguishing the target sequence from the negative control. To the best of our knowledge, this is the first report of the detection of target DNA from clinical samples using a tetrahedral DNA probe functionalized electrochemical biosensor. It displays that the DNA tetrahedra has a great potential application as a probe of the electrochemical biosensor to detect avian influenza A (H7N9) virus and other pathogens at the gene level, which will potentially aid the prevention and control of the disease caused by such pathogens.

  6. Disentangling the drivers of reduced long-distance seed dispersal by birds in an experimentally fragmented landscape.

    Science.gov (United States)

    Uriarte, María; Anciães, Marina; da Silva, Mariana T B; Rubim, Paulo; Johnson, Erik; Bruna, Emilio M

    2011-04-01

    Seed dispersal is a crucial component of plant population dynamics. Human landscape modifications, such as habitat destruction and fragmentation, can alter the abundance of fruiting plants and animal dispersers, foraging rates, vector movement, and the composition of the disperser community, all of which can singly or in concert affect seed dispersal. Here, we quantify and tease apart the effects of landscape configuration, namely, fragmentation of primary forest and the composition of the surrounding forest matrix, on individual components of seed dispersal of Heliconia acuminata, an Amazonian understory herb. First we identified the effects of landscape configuration on the abundance of fruiting plants and six bird disperser species. Although highly variable in space and time, densities of fruiting plants were similar in continuous forest and fragments. However, the two largest-bodied avian dispersers were less common or absent in small fragments. Second, we determined whether fragmentation affected foraging rates. Fruit removal rates were similar and very high across the landscape, suggesting that Heliconia fruits are a key resource for small frugivores in this landscape. Third, we used radiotelemetry and statistical models to quantify how landscape configuration influences vector movement patterns. Bird dispersers flew farther and faster, and perched longer in primary relative to secondary forests. One species also altered its movement direction in response to habitat boundaries between primary and secondary forests. Finally, we parameterized a simulation model linking data on fruit density and disperser abundance and behavior with empirical estimates of seed retention times to generate seed dispersal patterns in two hypothetical landscapes. Despite clear changes in bird movement in response to landscape configuration, our simulations demonstrate that these differences had negligible effects on dispersal distances. However, small fragments had reduced densities

  7. Assessment of missile hazards: identification of reference fragmentation patterns.

    Science.gov (United States)

    Gubinelli, Gianfilippo; Cozzani, Valerio

    2009-04-30

    Industrial accidents involving fragment projection were investigated. The analysis of fracture mechanics fundamentals allowed the exploration of the relations between the fracture characteristics and the final event leading to equipment collapse. Reference fragmentation patterns were defined on the basis of the geometrical characteristics of the categories of process vessels that are more frequently involved in fragmentation accidents. Primary scenarios leading to fragment projection were correlated to specific fragmentation patterns. A database reporting a detailed analysis of more than 140 vessel fragmentation events provided the data needed to support and validate the approach. The available data also allowed the calculation of the expected probability of fragment projection following vessel fragmentation, and the probability of the alternative fragmentation patterns with respect to the different accidental scenarios, based on the observed frequencies over the available data set.

  8. PREFIX-BASED LABELING ANNOTATION FOR EFFECTIVE XML FRAGMENTATION

    Directory of Open Access Journals (Sweden)

    Kok-Leong Koong

    2015-05-01

    Full Text Available XML is gradually employed as a standard of data exchange in web environment since its inception in the 90s until present. It serves as a data exchange between systems and other applications. Meanwhile the data volume has grown substantially in the web and thus effective methods of storing and retrieving these data is essential. One recommended way is physically or virtually fragments the large chunk of data and distributes the fragments into different nodes. Fragmentation design of XML document contains of two parts: fragmentation operation and fragmentation method. The three fragmentation operations are Horizontal, Vertical and Hybrid. It determines how the XML should be fragmented. This paper aims to give an overview on the fragmentation design consideration and subsequently, propose a fragmentation technique using number addressing.

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

    Directory of Open Access Journals (Sweden)

    Farrukh Saleem

    2011-08-01

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

  10. Large-scale avian influenza surveillance in wild birds throughout the United States.

    Science.gov (United States)

    Bevins, Sarah N; Pedersen, Kerri; Lutman, Mark W; Baroch, John A; Schmit, Brandon S; Kohler, Dennis; Gidlewski, Thomas; Nolte, Dale L; Swafford, Seth R; DeLiberto, Thomas J

    2014-01-01

    Avian influenza is a viral disease that primarily infects wild and domestic birds, but it also can be transmitted to a variety of mammals. In 2006, the United States of America Departments of Agriculture and Interior designed a large-scale, interagency surveillance effort that sought to determine if highly pathogenic avian influenza viruses were present in wild bird populations within the United States of America. This program, combined with the Canadian and Mexican surveillance programs, represented the largest, coordinated wildlife disease surveillance program ever implemented. Here we analyze data from 197,885 samples that were collected from over 200 wild bird species. While the initial motivation for surveillance focused on highly pathogenic avian influenza, the scale of the data provided unprecedented information on the ecology of avian influenza viruses in the United States, avian influenza virus host associations, and avian influenza prevalence in wild birds over time. Ultimately, significant advances in our knowledge of avian influenza will depend on both large-scale surveillance efforts and on focused research studies.

  11. Large-scale avian influenza surveillance in wild birds throughout the United States.

    Directory of Open Access Journals (Sweden)

    Sarah N Bevins

    Full Text Available Avian influenza is a viral disease that primarily infects wild and domestic birds, but it also can be transmitted to a variety of mammals. In 2006, the United States of America Departments of Agriculture and Interior designed a large-scale, interagency surveillance effort that sought to determine if highly pathogenic avian influenza viruses were present in wild bird populations within the United States of America. This program, combined with the Canadian and Mexican surveillance programs, represented the largest, coordinated wildlife disease surveillance program ever implemented. Here we analyze data from 197,885 samples that were collected from over 200 wild bird species. While the initial motivation for surveillance focused on highly pathogenic avian influenza, the scale of the data provided unprecedented information on the ecology of avian influenza viruses in the United States, avian influenza virus host associations, and avian influenza prevalence in wild birds over time. Ultimately, significant advances in our knowledge of avian influenza will depend on both large-scale surveillance efforts and on focused research studies.

  12. Multi-species patterns of avian cholera mortality in Nebraska's rainwater basin

    Science.gov (United States)

    Blanchong, Julie A.; Samuel, M.D.; Mack, G.

    2006-01-01

    Nebraska's Rainwater Basin (RWB) is a key spring migration area for millions of waterfowl and other avian species. Avian cholera has been endemic in the RWB since the 1970s and in some years tens of thousands of waterfowl have died from the disease. We evaluated patterns of avian cholera mortality in waterfowl species using the RWB during the last quarter of the 20th century. Mortality patterns changed between the years before (1976 - 1988) and coincident with (1989 - 1999) the dramatic increases in lesser snow goose abundance and mortality. Lesser snow geese (Chen caerulescens caerulescens) have commonly been associated with mortality events in the RWB and are known to carry virulent strains of Pasteurella multocida, the agent causing avian cholera. Lesser snow geese appeared to be the species most affected by avian cholera during 1989 - 1999; however, mortality in several other waterfowl species was positively correlated with lesser snow goose mortality. Coincident with increased lesser snow goose mortality, spring avian cholera outbreaks were detected earlier and ended earlier compared to 1976 - 1988. Dense concentrations of lesser snow geese may facilitate intraspecific disease transmission through bird-to-bird contact and wetland contamination. Rates of interspecific avian cholera transmission within the waterfowl community, however, are difficult to determine.

  13. Avian malaria, ecological host traits and mosquito abundance in southeastern Amazonia.

    Science.gov (United States)

    Fecchio, Alan; Ellis, Vincenzo A; Bell, Jeffrey A; Andretti, Christian B; D'Horta, Fernando M; Silva, Allan M; Tkach, Vasyl V; Weckstein, Jason D

    2017-03-27

    Avian malaria is a vector transmitted disease caused by Plasmodium and recent studies suggest that variation in its prevalence across avian hosts is correlated with a variety of ecological traits. Here we examine the relationship between prevalence and diversity of Plasmodium lineages in southeastern Amazonia and: (1) host ecological traits (nest location, nest type, flocking behaviour and diet); (2) density and diversity of avian hosts; (3) abundance and diversity of mosquitoes; and (4) season. We used molecular methods to detect Plasmodium in blood samples from 675 individual birds of 120 species. Based on cytochrome b sequences, we recovered 89 lineages of Plasmodium from 136 infected individuals sampled across seven localities. Plasmodium prevalence was homogeneous over time (dry season and flooding season) and space, but heterogeneous among 51 avian host species. Variation in prevalence among bird species was not explained by avian ecological traits, density of avian hosts, or mosquito abundance. However, Plasmodium lineage diversity was positively correlated with mosquito abundance. Interestingly, our results suggest that avian host traits are less important determinants of Plasmodium prevalence and diversity in southeastern Amazonia than in other regions in which they have been investigated.

  14. HIERARCHICAL FRAGMENTATION OF THE ORION MOLECULAR FILAMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Satoko; Ho, Paul T. P.; Su, Yu-Nung [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China); Teixeira, Paula S. [Institut fuer Astrophysik, Universitaet Wien, Tuerkenschanzstrasse 17, A-1180, Wien (Austria); Zapata, Luis A., E-mail: satoko_t@asiaa.sinica.edu.tw [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, Morelia, Michoacan 58090 (Mexico)

    2013-01-20

    We present a high angular resolution map of the 850 {mu}m continuum emission of the Orion Molecular Cloud-3 (OMC 3) obtained with the Submillimeter Array (SMA); the map is a mosaic of 85 pointings covering an approximate area of 6.'5 Multiplication-Sign 2.'0 (0.88 Multiplication-Sign 0.27 pc). We detect 12 spatially resolved continuum sources, each with an H{sub 2} mass between 0.3-5.7 M {sub Sun} and a projected source size between 1400-8200 AU. All the detected sources are on the filamentary main ridge (n{sub H{sub 2}}{>=}10{sup 6} cm{sup -3}), and analysis based on the Jeans theorem suggests that they are most likely gravitationally unstable. Comparison of multi-wavelength data sets indicates that of the continuum sources, 6/12 (50%) are associated with molecular outflows, 8/12 (67%) are associated with infrared sources, and 3/12 (25%) are associated with ionized jets. The evolutionary status of these sources ranges from prestellar cores to protostar phase, confirming that OMC-3 is an active region with ongoing embedded star formation. We detect quasi-periodical separations between the OMC-3 sources of Almost-Equal-To 17''/0.035 pc. This spatial distribution is part of a large hierarchical structure that also includes fragmentation scales of giant molecular cloud ( Almost-Equal-To 35 pc), large-scale clumps ( Almost-Equal-To 1.3 pc), and small-scale clumps ( Almost-Equal-To 0.3 pc), suggesting that hierarchical fragmentation operates within the Orion A molecular cloud. The fragmentation spacings are roughly consistent with the thermal fragmentation length in large-scale clumps, while for small-scale cores it is smaller than the local fragmentation length. These smaller spacings observed with the SMA can be explained by either a helical magnetic field, cloud rotation, or/and global filament collapse. Finally, possible evidence for sequential fragmentation is suggested in the northern part of the OMC-3 filament.

  15. Identification of Diarrheagenic Escherichia coli Strains from Avian Organic Fertilizers

    Directory of Open Access Journals (Sweden)

    Juan Puño-Sarmiento

    2014-08-01

    Full Text Available The Brazilian poultry industry generates large amounts of organic waste, such as chicken litter, which is often used in agriculture. Among the bacteria present in organic fertilizer are members of the Enterobacteriaceae family. The objective of this study was to detect the presence of diarrheagenic Escherichia coli (DEC strains in avian organic fertilizer, and assess the potential damage they can cause in humans due to antimicrobial resistance. The presence of DEC pathotypes and phylogenetic groups were detected by multiplex-PCR. Phenotypic assays, such as tests for adhesion, cytotoxicity activity, biofilm formation and especially antimicrobial susceptibility, were performed. Fifteen DEC strains from 64 E. coli were isolated. Among these, four strains were classified as enteropathogenic (EPEC; 6.2%, three strains as Shiga toxin-producing (STEC; 4.7%, 10 strains as enteroaggregative (EAEC; 12.5%, but two of these harbored the eaeA gene too. The low number of isolated strains was most likely due to the composting process, which reduces the number of microorganisms. These strains were able to adhere to HEp-2 and HeLa cells and produce Shiga-toxins and biofilms; in addition, some of the strains showed antimicrobial resistance, which indicates a risk of the transfer of resistance genes to human E. coli. These results showed that DEC strains isolated from avian organic fertilizers can cause human infections.

  16. Neural correlates of executive control in the avian brain.

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    Jonas Rose

    2005-06-01

    Full Text Available Executive control, the ability to plan one's behaviour to achieve a goal, is a hallmark of frontal lobe function in humans and other primates. In the current study we report neural correlates of executive control in the avian nidopallium caudolaterale, a region analogous to the mammalian prefrontal cortex. Homing pigeons (Columba livia performed a working memory task in which cues instructed them whether stimuli should be remembered or forgotten. When instructed to remember, many neurons showed sustained activation throughout the memory period. When instructed to forget, the sustained activation was abolished. Consistent with the neural data, the behavioural data showed that memory performance was high after instructions to remember, and dropped to chance after instructions to forget. Our findings indicate that neurons in the avian nidopallium caudolaterale participate in one of the core forms of executive control, the control of what should be remembered and what should be forgotten. This form of executive control is fundamental not only to working memory, but also to all cognition.

  17. 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.

  18. mcr-1 identified in Avian Pathogenic Escherichia coli (APEC)

    Science.gov (United States)

    Lima Barbieri, Nicolle; Nielsen, Daniel W.; Wannemuehler, Yvonne; Cavender, Tia; Hussein, Ashraf; Yan, Shi-gan; Nolan, Lisa K.; Logue, Catherine M.

    2017-01-01

    Antimicrobial resistance associated with colistin has emerged as a significant concern worldwide threatening the use of one of the most important antimicrobials for treating human disease. Here, we examined a collection (n = 980) of Avian Pathogenic Escherichia coli (APEC) isolated from poultry with colibacillosis from the US and internationally for the presence of mcr-1 and mcr-2, genes known to encode colistin resistance. Included in the analysis was an additional set of avian fecal E. coli (AFEC) (n = 220) isolates from healthy birds for comparative analysis. The mcr-1 gene was detected in a total of 12 isolates recovered from diseased production birds from China and Egypt. No mcr genes were detected in the healthy fecal isolates. The full mcr-1 gene from positive isolates was sequenced using specifically designed primers and were compared with sequences currently described in NCBI. mcr-1 positive isolates were also assessed for phenotypic colistin resistance and extended spectrum beta lactam phenotypes and genotypes. This study has identified mcr-1 in APEC isolates dating back to at least 2010 and suggests that animal husbandry practices could result in a potential source of resistance to the human food chain in countries where application of colistin in animal health is practiced. PMID:28264015

  19. Brain size as a driver of avian escape strategy.

    Science.gov (United States)

    Samia, Diogo S M; Pape Møller, Anders; Blumstein, Daniel T

    2015-07-03

    After detecting an approaching predator, animals make a decision when to flee. Prey will initiate flight soon after detecting a predator so as to minimize attentional costs related to on-going monitoring of the whereabouts of the predator. Such costs may compete with foraging and other maintenance activities and hence be larger than the costs of immediate flight. The drivers of interspecific variation in escape strategy are poorly known. Here we investigated the morphological, life history and natural history traits that correlate with variation in avian escape strategy across a sample of 96 species of birds. Brain mass, body size, habitat structure and group size were the main predictors of escape strategy. The direction of the effect of these traits was consistent with selection for a reduction of monitoring costs. Therefore, attentional costs depend on relative brain size, which determines the ability to monitor the whereabouts of potential predators and the difficulty of this task as reflected by habitat and social complexity. Thus brain size, and the cognitive functions associated with it, constitute a general framework for explaining the effects of body size, habitat structure and sociality identified as determinants of avian escape strategy.

  20. Avian influenza infection alters fecal odor in mallards.

    Directory of Open Access Journals (Sweden)

    Bruce A Kimball

    Full Text Available Changes in body odor are known to be a consequence of many diseases. Much of the published work on disease-related and body odor changes has involved parasites and certain cancers. Much less studied have been viral diseases, possibly due to an absence of good animal model systems. Here we studied possible alteration of fecal odors in animals infected with avian influenza viruses (AIV. In a behavioral study, inbred C57BL/6 mice were trained in a standard Y-maze to discriminate odors emanating from feces collected from mallard ducks (Anas platyrhynchos infected with low-pathogenic avian influenza virus compared to fecal odors from non-infected controls. Mice could discriminate odors from non-infected compared to infected individual ducks on the basis of fecal odors when feces from post-infection periods were paired with feces from pre-infection periods. Prompted by this indication of odor change, fecal samples were subjected to dynamic headspace and solvent extraction analyses employing gas chromatography/mass spectrometry to identify chemical markers indicative of AIV infection. Chemical analyses indicated that AIV infection was associated with a marked increase of acetoin (3-hydroxy-2-butanone in feces. These experiments demonstrate that information regarding viral infection exists via volatile metabolites present in feces. Further, they suggest that odor changes following virus infection could play a role in regulating behavior of conspecifics exposed to infected individuals.

  1. 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.

  2. Identification of diarrheagenic Escherichia coli strains from avian organic fertilizers.

    Science.gov (United States)

    Puño-Sarmiento, Juan; Gazal, Luis Eduardo; Medeiros, Leonardo P; Nishio, Erick K; Kobayashi, Renata K T; Nakazato, Gerson

    2014-08-28

    The Brazilian poultry industry generates large amounts of organic waste, such as chicken litter, which is often used in agriculture. Among the bacteria present in organic fertilizer are members of the Enterobacteriaceae family. The objective of this study was to detect the presence of diarrheagenic Escherichia coli (DEC) strains in avian organic fertilizer, and assess the potential damage they can cause in humans due to antimicrobial resistance. The presence of DEC pathotypes and phylogenetic groups were detected by multiplex-PCR. Phenotypic assays, such as tests for adhesion, cytotoxicity activity, biofilm formation and especially antimicrobial susceptibility, were performed. Fifteen DEC strains from 64 E. coli were isolated. Among these, four strains were classified as enteropathogenic (EPEC; 6.2%), three strains as Shiga toxin-producing (STEC; 4.7%), 10 strains as enteroaggregative (EAEC; 12.5%), but two of these harbored the eaeA gene too. The low number of isolated strains was most likely due to the composting process, which reduces the number of microorganisms. These strains were able to adhere to HEp-2 and HeLa cells and produce Shiga-toxins and biofilms; in addition, some of the strains showed antimicrobial resistance, which indicates a risk of the transfer of resistance genes to human E. coli. These results showed that DEC strains isolated from avian organic fertilizers can cause human infections.

  3. The motor origins of human and avian song structure.

    Science.gov (United States)

    Tierney, Adam T; Russo, Frank A; Patel, Aniruddh D

    2011-09-13

    Human song exhibits great structural diversity, yet certain aspects of melodic shape (how pitch is patterned over time) are widespread. These include a predominance of arch-shaped and descending melodic contours in musical phrases, a tendency for phrase-final notes to be relatively long, and a bias toward small pitch movements between adjacent notes in a melody [Huron D (2006) Sweet Anticipation: Music and the Psychology of Expectation (MIT Press, Cambridge, MA)]. What is the origin of these features? We hypothesize that they stem from motor constraints on song production (i.e., the energetic efficiency of their underlying motor actions) rather than being innately specified. One prediction of this hypothesis is that any animals subject to similar motor constraints on song will exhibit similar melodic shapes, no matter how distantly related those animals are to humans. Conversely, animals who do not share similar motor constraints on song will not exhibit convergent melodic shapes. Birds provide an ideal case for testing these predictions, because their peripheral mechanisms of song production have both notable similarities and differences from human vocal mechanisms [Riede T, Goller F (2010) Brain Lang 115:69-80]. We use these similarities and differences to make specific predictions about shared and distinct features of human and avian song structure and find that these predictions are confirmed by empirical analysis of diverse human and avian song samples.

  4. Economic epidemiology of avian influenza on smallholder poultry farms.

    Science.gov (United States)

    Boni, Maciej F; Galvani, Alison P; Wickelgren, Abraham L; Malani, Anup

    2013-12-01

    Highly pathogenic avian influenza (HPAI) is often controlled through culling of poultry. Compensating farmers for culled chickens or ducks facilitates effective culling and control of HPAI. However, ensuing price shifts can create incentives that alter the disease dynamics of HPAI. Farmers control certain aspects of the dynamics by setting a farm size, implementing infection control measures, and determining the age at which poultry are sent to market. Their decisions can be influenced by the market price of poultry which can, in turn, be set by policy makers during an HPAI outbreak. Here, we integrate these economic considerations into an epidemiological model in which epidemiological parameters are determined by an outside agent (the farmer) to maximize profit from poultry sales. Our model exhibits a diversity of behaviors which are sensitive to (i) the ability to identify infected poultry, (ii) the average price of infected poultry, (iii) the basic reproductive number of avian influenza, (iv) the effect of culling on the market price of poultry, (v) the effect of market price on farm size, and (vi) the effect of poultry density on disease transmission. We find that under certain market and epidemiological conditions, culling can increase farm size and the total number of HPAI infections. Our model helps to inform the optimization of public health outcomes that best weigh the balance between public health risk and beneficial economic outcomes for farmers.

  5. Novel Picornavirus Associated with Avian Keratin Disorder in Alaskan Birds

    Directory of Open Access Journals (Sweden)

    Maxine Zylberberg

    2016-07-01

    Full Text Available Avian keratin disorder (AKD, characterized by debilitating overgrowth of the avian beak, was first documented in black-capped chickadees (Poecile atricapillus in Alaska. Subsequently, similar deformities have appeared in numerous species across continents. Despite the widespread distribution of this emerging pathology, the cause of AKD remains elusive. As a result, it is unknown whether suspected cases of AKD in the afflicted species are causally linked, and the impacts of this pathology at the population and community levels are difficult to evaluate. We applied unbiased, metagenomic next-generation sequencing to search for candidate pathogens in birds affected with AKD. We identified and sequenced the complete coding region of a novel picornavirus, which we are calling poecivirus. Subsequent screening of 19 AKD-affected black-capped chickadees and 9 control individuals for the presence of poecivirus revealed that 19/19 (100% AKD-affected individuals were positive, while only 2/9 (22% control individuals were infected with poecivirus. Two northwestern crows (Corvus caurinus and two red-breasted nuthatches (Sitta canadensis with AKD-consistent pathology also tested positive for poecivirus. We suggest that poecivirus is a candidate etiological agent of AKD.

  6. Molecular diversity of avian schistosomes in Danish freshwater snails.

    Science.gov (United States)

    Christiansen, Anne Ø; Olsen, Annette; Buchmann, Kurt; Kania, Per W; Nejsum, Peter; Vennervald, Birgitte J

    2016-03-01

    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 and subjected to molecular investigation by sequencing and phylogenetic analysis of the 5.8S and ITS2 ribosomal DNA for species identification. Additionally, snail hosts belonging to the genus Radix were identified by sequencing and phylogenetic analysis of partial ITS2 ribosomal DNA. Three out of 499 snails shed different species of Trichobilharzia cercariae: Trichobilharzia szidati was isolated from L. stagnalis, Trichobilharzia franki from Radix auricularia and Trichobilharzia regenti from Radix peregra. In the light of the public health risk represented by bird schistosomes, these findings are of concern and, particularly, the presence of the potentially neuro-pathogenic species, T. regenti, in Danish freshwaters calls for attention.

  7. THE AVIAN FLU IMPACT ON THE ROMANIAN POULTRY MARKET

    Directory of Open Access Journals (Sweden)

    Silvius Stanciu

    2015-05-01

    Full Text Available Poultry meat represents one of the most dynamic branches of the local meat production. The poultry sector represents a good quality protein source, at an acceptable price as compared to other animal production domains. There has been an ascending evolution of the sector after the year 2000, although there appeared a series of discontinuities that affected agricultural production, mainly on a short-term basis. The Avian Flu led to 190 million euros’ worth losses at the level of Romanian national economy. Low consumption due to the impact was a short-term consequence, being rapidly amortized by the Romanian producers. The lack of some business continuity insurance measures can further affect the poultry meat sector, which does not have the necessary robustness needed in case of larger shocks. The following article proposes an analysis of the Avian Flu crisis economic effects on the Romanian meat sector, and it is part of a general framework of research regarding the Romanian food chain resilience to critical situations.

  8. Species formation by host shifting in avian malaria parasites.

    Science.gov (United States)

    Ricklefs, Robert E; Outlaw, Diana C; Svensson-Coelho, Maria; Medeiros, Matthew C I; Ellis, Vincenzo A; Latta, Steven

    2014-10-14

    The malaria parasites (Apicomplexa: Haemosporida) of birds are believed to have diversified across the avian host phylogeny well after the origin of most major host lineages. Although many symbionts with direct transmission codiversify with their hosts, mechanisms of species formation in vector-borne parasites, including the role of host shifting, are poorly understood. Here, we examine the hosts of sister lineages in a phylogeny of 181 putative species of malaria parasites of New World terrestrial birds to determine the role of shifts between host taxa in the formation of new parasite species. We find that host shifting, often across host genera and families, is the rule. Sympatric speciation by host shifting would require local reproductive isolation as a prerequisite to divergent selection, but this mechanism is not supported by the generalized host-biting behavior of most vectors of avian malaria parasites. Instead, the geographic distribution of individual parasite lineages in diverse hosts suggests that species formation is predominantly allopatric and involves host expansion followed by local host-pathogen coevolution and secondary sympatry, resulting in local shifting of parasite lineages across hosts.

  9. Fragmentation of massive dense cores down to ≲ 1000 AU: Relation between fragmentation and density structure

    Energy Technology Data Exchange (ETDEWEB)

    Palau, Aina; Girart, Josep M. [Institut de Ciències de l' Espai (CSIC-IEEC), Campus UAB-Facultat de Ciències, Torre C5-parell 2, E-08193 Bellaterra, Catalunya (Spain); Estalella, Robert [Departament d' Astronomia i Meteorologia (IEEC-UB), Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès, 1, E-08028 Barcelona (Spain); Fuente, Asunción [Observatorio Astronómico Nacional, P.O. Box 112, E-28803 Alcalá de Henares, Madrid (Spain); Fontani, Francesco; Sánchez-Monge, Álvaro [Osservatorio Astrofisico di Arcetri, INAF, Lago E. Fermi 5, I-50125 Firenze (Italy); Commerçon, Benoit; Hennebelle, Patrick [Laboratoire de Radioastronomie, UMR CNRS 8112, École Normale Supérieure et Observatoire de Paris, 24 rue Lhomond, F-75231 Paris Cedex 05 (France); Busquet, Gemma [INAF-Istituto di Astrofisica e Planetologia Spaziali, Area di Recerca di Tor Vergata, Via Fosso Cavaliere 100, I-00133 Roma (Italy); Bontemps, Sylvain [Université de Bordeaux, LAB, UMR 5804, F-33270 Floirac (France); Zapata, Luis A. [Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090 Morelia, Michoacán (Mexico); Zhang, Qizhou [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Di Francesco, James, E-mail: palau@ieec.uab.es [Department of Physics and Astronomy, University of Victoria, P.O. Box 355, STN CSC, Victoria, BC, V8W 3P6 (Canada)

    2014-04-10

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 μm (or 1.2 mm in two cases) and the spectral energy distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. Even though the estimated fragmentation level is strictly speaking a lower limit, its relative value is significant and several trends could be explored with our data. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered the effects of rotational-to-gravitational energy ratio, non-thermal velocity dispersion, and turbulence mode on the density structure of the cores, and found that compressive turbulence seems to yield higher central densities. Finally, a possible explanation for the origin of cores with concentrated density profiles, which are the cores showing no fragmentation, could be related with a strong magnetic field, consistent with the outcome of radiation magnetohydrodynamic simulations.

  10. Assessment of Fragmentation Performance of Blast-enhanced Explosive Fragmentation Munitions

    Science.gov (United States)

    2010-10-01

    aluminized blast-enhanced PAX-Al composition. The experimental assessment of the fragmentation performance of tested charges was accomplished using...charges, rapid expansion of high pressure detonation products results in high-strain high-strain-rate dilation of the hardened steel shell, which...eventually ruptures generating a “spray” of high-velocity steel fragments. Defining the longitudinal axis of the munition as the polar axis z, the

  11. A cross-sectional study of avian influenza in one district of Guangzhou, 2013.

    Directory of Open Access Journals (Sweden)

    Haiming Zhang

    Full Text Available Since Feb, 2013, more than 100 human beings had been infected with novel H7N9 avian influenza virus. As of May 2013, several H7N9 viruses had been found in retail live bird markets (LBMs in Guangdong province of southern China where several human cases were confirmed later. However, the real avian influenza virus infection status especially H7N9 in Guangzhou remains unclear. Therefore, a cross-sectional study of avian influenza in commercial poultry farms, the wholesale LBM and retail LBMs in one district of Guangzhou was conducted from October to November, 2013. A total of 1505 cloacal and environmental samples from 52 commercial poultry farms, 1 wholesale LBM and 18 retail LBMs were collected and detected using real-time RT-PCR for type A, H7, H7N9 and H9 subtype avian influenza virus, respectively. Of all the flocks randomly sampled, 6 farms, 12 vendors of the wholesale LBM and 18 retail LBMs were type A avian influenza virus positive with 0, 3 and 11 positive for H9, respectively. The pooled prevalence and individual prevalence of type A avian influenza virus were 33.9% and 7.9% which for H9 subtype was 7.6% and 1.6%, respectively. None was H7 and H7N9 subtype virus positive. Different prevalence and prevalence ratio were found in different poultry species with partridges having the highest prevalence for both type A and H9 subtype avian influenza virus. Our results suggest that LBM may have a higher risk for sustaining and transmission of avian influenza virus than commercial poultry farms. The present study also indicates that different species may play different roles in the evolution and transmission of avian influenza virus. Therefore, risk-based surveillance and management measures should be conducted in future in this area.

  12. Subclinical avian hepatitis E virus infection in layer flocks in the United States.

    Science.gov (United States)

    Gerber, Priscilla F; Trampel, Darrell W; Willinghan, Eric M; Billam, Padma; Meng, Xiang-Jin; Opriessnig, Tanja

    2015-12-01

    The objective of this study was to determine patterns of avian HEV infection in naturally infected chicken farms. A total of 310 serum samples and 62 pooled fecal samples were collected from 62 chicken flocks on seven commercial in-line egg farms in the Midwestern United States and tested for avian HEV circulation. Serum samples were tested for the presence of anti-avian HEV IgY antibodies by a fluorescent microbead immunoassay (FMIA) which was developed for this study. The FMIA was validated using archived samples of chickens with known exposure (n = 96) and compared to the results obtained with an enzyme-linked immunosorbent assay (ELISA) based on the same capture antigen. There was an overall substantial agreement between the two assays (κ = 0.63) with earlier detection of positive chickens by the FMIA (P = 0.04). On the seven farms investigated, the overall prevalence of anti-avian HEV IgY antibodies in serum samples from commercial chickens was 44.8% (20-82% per farm). Fecal samples were tested for avian HEV RNA by a nested reverse-transcriptase PCR. The overall detection rate of avian HEV RNA in fecal samples was 62.9% (0-100% per farm). Sequencing analyses of partial helicase and capsid genes showed that different avian HEV genotype 2 strains were circulating within a farm. However, no correlation was found between avian HEV RNA detection and egg production, egg weight or mortality. In conclusion, avian HEV infection is widespread among clinically healthy laying hens in the United States.

  13. Identification of two neutralization epitopes on the capsid protein of avian hepatitis E virus.

    Science.gov (United States)

    Zhou, E-M; Guo, H; Huang, F F; Sun, Z F; Meng, X J

    2008-02-01

    Avian hepatitis E virus (avian HEV) is genetically and antigenically related to human HEV, the causative agent of hepatitis E. To identify the neutralizing epitopes on the capsid (ORF2) protein of avian HEV, four mAbs (7B2, 1E11, 10A2 and 5G10) against recombinant avian HEV ORF2 protein were generated. mAbs 7B2, 1E11 and 10A2 blocked each other for binding to avian HEV ORF2 protein in a competitive ELISA, whereas 5G10 did not block the other mAbs, suggesting that 7B2, 1E11 and 10A2 recognize the same or overlapping epitopes and 5G10 recognizes a different one. The epitopes recognized by 7B2, 1E11 and 10A2, and by 5G10 were mapped by Western blotting between aa 513 and 570, and between aa 476 and 513, respectively. mAbs 1E11, 10A2 and 5G10 were shown to bind to avian HEV particles in vitro, although only 5G10 reacted to viral antigens in transfected LMH cells. To assess the neutralizing activities of the mAbs, avian HEV was incubated in vitro with each mAb before inoculation into specific-pathogen-free chickens. Both viraemia and faecal virus shedding were delayed in chickens inoculated with the mixtures of avian HEV and 1E11, 10A2 or 5G10, suggesting that these three mAbs partially neutralize avian HEV.

  14. A cross-sectional study of avian influenza in one district of Guangzhou, 2013.

    Science.gov (United States)

    Zhang, Haiming; Peng, Cong; Duan, Xiaodong; Shen, Dan; Lan, Guanghua; Xiao, Wutao; Tan, Hai; Wang, Ling; Hou, Jialei; Zhu, Jiancui; He, Riwen; Zhang, Haibing; Zheng, Lilan; Yang, Jianyu; Zhang, Zhen; Zhou, Zhiwei; Li, Wenhua; Hu, Mailing; Zhong, Jinhui; Chen, Yuhua

    2014-01-01

    Since Feb, 2013, more than 100 human beings had been infected with novel H7N9 avian influenza virus. As of May 2013, several H7N9 viruses had been found in retail live bird markets (LBMs) in Guangdong province of southern China where several human cases were confirmed later. However, the real avian influenza virus infection status especially H7N9 in Guangzhou remains unclear. Therefore, a cross-sectional study of avian influenza in commercial poultry farms, the wholesale LBM and retail LBMs in one district of Guangzhou was conducted from October to November, 2013. A total of 1505 cloacal and environmental samples from 52 commercial poultry farms, 1 wholesale LBM and 18 retail LBMs were collected and detected using real-time RT-PCR for type A, H7, H7N9 and H9 subtype avian influenza virus, respectively. Of all the flocks randomly sampled, 6 farms, 12 vendors of the wholesale LBM and 18 retail LBMs were type A avian influenza virus positive with 0, 3 and 11 positive for H9, respectively. The pooled prevalence and individual prevalence of type A avian influenza virus were 33.9% and 7.9% which for H9 subtype was 7.6% and 1.6%, respectively. None was H7 and H7N9 subtype virus positive. Different prevalence and prevalence ratio were found in different poultry species with partridges having the highest prevalence for both type A and H9 subtype avian influenza virus. Our results suggest that LBM may have a higher risk for sustaining and transmission of avian influenza virus than commercial poultry farms. The present study also indicates that different species may play different roles in the evolution and transmission of avian influenza virus. Therefore, risk-based surveillance and management measures should be conducted in future in this area.

  15. Fragmentation of massive dense cores down to ~1000 AU: Relation between fragmentation and density structure

    CERN Document Server

    Palau, Aina; Girart, J M; Fuente, A; Fontani, F; Commercon, B; Busquet, G; Bontemps, S; Sanchez-Monge, A; Zapata, L A; Zhang, Q; Hennebelle, P; Di Francesco, J

    2014-01-01

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 micron (or 1.2 mm in two cases) and the Spectral Energy Distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered th...

  16. Detecting Cortex Fragments During Bacterial Spore Germination.

    Science.gov (United States)

    Francis, Michael B; Sorg, Joseph A

    2016-06-25

    The process of endospore germination in Clostridium difficile, and other Clostridia, increasingly is being found to differ from the model spore-forming bacterium, Bacillus subtilis. Germination is triggered by small molecule germinants and occurs without the need for macromolecular synthesis. Though differences exist between the mechanisms of spore germination in species of Bacillus and Clostridium, a common requirement is the hydrolysis of the peptidoglycan-like cortex which allows the spore core to swell and rehydrate. After rehydration, metabolism can begin and this, eventually, leads to outgrowth of a vegetative cell. The detection of hydrolyzed cortex fragments during spore germination can be difficult and the modifications to the previously described assays can be confusing or difficult to reproduce. Thus, based on our recent report using this assay, we detail a step-by-step protocol for the colorimetric detection of cortex fragments during bacterial spore germination.

  17. HCH for Checking Containment of XPath Fragment

    Institute of Scientific and Technical Information of China (English)

    Jian-Hua Feng; Yu-Guo Liao; Yong Zhang

    2007-01-01

    XPath is ubiquitous in XML applications for navigating XML trees and selecting a set of element nodes. In XPath query processing, one of the most important issues is how to efficiently check containment relationship between two XPath expressions. To get out of the intricacy and complexity caused by numerous XPath features, we investigate this issue on a frequently used fragment of XPath expressions that consists of node tests, the child axis (/), the descendant axis (//), branches ([]) and label wildcards (*). Prior work has shown that homomorphism technology can be used for containment checking. However, homomorphism is the sufficient but not necessary condition for containment. For special classes of this fragment, the homomorphism algorithm returns false negatives. To address this problem, this paper proposes two containment techniques, conditioned homomorphism and hidden conditioned homomorphism, and then presents sound algorithms for checking containment. Experimental results confirm the practicability and efficiency of the proposed algorithms.

  18. Avian bornavirus in free-ranging waterfowl in North America and Europe

    DEFF Research Database (Denmark)

    Brinkmann, Jesper; Thomsen, Anders F.; Bertelsen, Mads Frost;

    The first avian bornavirus (ABV) was identified in 2008 by researchers investigating the cause of proventricular dilation disease in psittacine birds 3,4. A distinctly separate genotype (ABV-CG) was discovered in 2009 in association with neurological disease in free-ranging Canada geese (Branta...... was identified in mallard ducks (Anas platyrhynchos) 2. In order to determine whether avian bornavirus was present in European waterfowl, the brains of 333 hunter killed geese in Denmark were examined by real time RT-PCR for the presence of avian bornavirus; seven birds (2.1%) were positive. Sequences were 98...

  19. Genome characterisation of the newly discovered avian influenza A H5N7 virus subtype combination

    DEFF Research Database (Denmark)

    Bragstad, K.; Jørgensen, Poul Henrik; Handberg, K.J.;

    2007-01-01

    In Denmark, in 2003, a previously unknown subtype combination of avian influenza A virus, H5N7 (A/Mallard/Denmark/64650/03), was isolated from a flock of 12,000 mallards. The H5N7 subtype combination might be a reassortant between recent European avian influenza A H5, H7, and a third subtype....../Duck/Hong Kong/3096/99 (H6N2) and A/WDk/ST/1737/2000 (H6N8), respectively. All genes of the H5N7 strain were of avian origin, and no further evidence of pathogenicity to humans has been found....

  20. Inhomogeneous Fragmentation of the Rolling Tachyon

    OpenAIRE

    Felder, Gary N; Kofman, Lev

    2004-01-01

    Dirac-Born-Infeld type effective actions reproduce many aspects of string theory classical tachyon dynamics of unstable Dp-branes. The inhomogeneous tachyon field rolling from the top of its potential forms topological defects of lower codimensions. In between them, as we show, the tachyon energy density fragments into a p-dimensional web-like high density network evolving with time. We present an analytic asymptotic series solution of the non-linear equations for the inhomogeneous tachyon an...