Science.gov

Sample records for avian igy-fc fragment

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

    PubMed

    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. Avian nest success in midwestern forests fragmented by agriculture

    USGS Publications Warehouse

    Knutson, M.G.; Friberg, M.A.; Niemi, G.J.; Newton, W.E.

    2004-01-01

    Knutson et al. (2004) report the results of an avian nest success study conducted to investigate how forest-bird nest success varied by nest location and type as well as by landscape context from 1996 to 1998 in an agricultural region of southwestern Minnesota, and southwestern Wisconsin, and northeastern Iowa. The authors found an overall Mayfield adjusted nest success of 48%, 82% for cavity-nesting species, and 42% for cup-nesting species. Common species varied from 23% for American Redstart (Setophaga ruticilla) to 43% for the Eastern Wood-Pewee (Contopus virens). Nest success was lowest for open-cup nesters, species that reject Brown-headed Cowbird (Molothrus ater) eggs, species that next near forest edges, and Neotropical migrants. These tendencies were consistent across the years of the study. Assessments of nest success considering surrounding landscape metrics indicated that forest area may not be a strong indicator of nest success in landscapes where all the available forests are fragmented.

  3. Avian nest success in midwestern forests fragmented by agriculture

    USGS Publications Warehouse

    Knutson, M.G.; Niemi, G.J.; Newton, W.E.; Friberg, M.A.

    2004-01-01

    We studied how forest-bird nest success varied by landscape context from 1996 to 1998 in an agricultural region of southeastern Minnesota, southwestern Wisconsin, and northeastern Iowa. Nest success was 48% for all nests, 82% for cavity-nesting species, and 42% for cup-nesting species. Mayfield-adjusted nest success for five common species ranged from 23% for the American Redstart (Setophaga ruticilla) to 43% for the Eastern Wood-Pewee (Contopus virens). Nest success was lowest for open-cup nesters, species that reject Brown-headed Cowbird (Molothrus ater) eggs, species that nest near forest edges, and Neo-tropical migrants. The proportion of forest core area in a 5-km radius around the plot had a weakly negative relationship with daily survival rate of nests for all species pooled and for medium or high canopy nesters, species associated with interior and edge habitats, open-cup nesters, and nests located between 75 and 199 m from an edge. The proportion of forest core area was positively related to daily survival rate only for ground and low nesters. Our findings are in contrast to a number of studies from the eastern United States reporting strong positive associations between forest area and nesting success. Supported models of habitat associations changed with the spatial scale of analysis and included variables not often considered in studies of forest birds, including the proportion of water, shrubs, and grasslands in the landscape. Forest area may not be a strong indicator of nest success in landscapes where all the available forests are fragmented.

  4. Does avian species richness in natural patch mosaics follow the forest fragmentation paradigm?

    USGS Publications Warehouse

    Pavlacky, D.C., Jr.; Anderson, S.H.

    2007-01-01

    As one approaches the north-eastern limit of pinyon (Pinus spp.) juniper (Juniperus spp.) vegetation on the Colorado Plateau, USA, woodland patches become increasingly disjunct, grading into sagebrush (Artemisia spp.)-dominated landscapes. Patterns of avian species richness in naturally heterogeneous forests may or may not respond to patch discontinuity in the same manner as bird assemblages in fragmented agricultural systems. We used observational data from naturally patchy woodlands and predictions derived from studies of human-modified agricultural forests to estimate the effects of patch area, shape, isolation and distance to contiguous woodland on avian species richness. We predicted that patterns of species richness in naturally patchy juniper woodlands would differ from those observed in fragmented agricultural systems. Our objectives were to (1) estimate the effect of naturally occurring patch structure on avian species richness with respect to habitat affinity and migratory strategy and (2) assess the concordance of the effects to predictions from agricultural forest systems. We used the analogy between populations and communities to estimate species richness, where species are treated as individuals in the application of traditional capture-recapture theory. Information-theoretic model selection showed that overall species richness was explained primarily by the species area relationship. There was some support for a model with greater complexity than the equilibrium theory of island biogeography where the isolation of large patches resulted in greater species richness. Species richness of woodland-dwelling birds was best explained by the equilibrium hypothesis with partial landscape complementation by open-country species in isolated patches. Species richness within specific migratory strategies showed concomitant increases and no shifts in species composition along the patch area gradient. Our results indicate that many patterns of species richness

  5. Matrix Intensification Alters Avian Functional Group Composition in Adjacent Rainforest Fragments

    PubMed Central

    Deikumah, Justus P.; McAlpine, Clive A.; Maron, Martine

    2013-01-01

    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. PMID:24058634

  6. Habitat Fragmentation and Ecological Traits Influence the Prevalence of Avian Blood Parasites in a Tropical Rainforest Landscape

    PubMed Central

    Laurance, Susan G. W.; Jones, Dean; Westcott, David; Mckeown, Adam; Harrington, Graham; Hilbert, David W.

    2013-01-01

    In the tropical rainforests of northern Australia, we investigated the effects of habitat fragmentation and ecological parameters on the prevalence of blood-borne parasites (Plasmodium and Haemoproteus) in bird communities. Using mist-nets on forest edges and interiors, we sampled bird communities across six study sites: 3 large fragments (20–85 ha) and 3 continuous-forest sites. From 335 mist-net captures, we recorded 28 bird species and screened 299 bird samples with PCR to amplify and detect target DNA. Of the 28 bird species sampled, 19 were infected with Plasmodium and/or Haemoproteus and 9 species were without infection. Over one third of screened birds (99 individuals) were positive for Haemoproteus and/or Plasmodium. In forest fragments, bird capture rates were significantly higher than in continuous forests, but bird species richness did not differ. Unexpectedly, we found that the prevalence of the dominant haemosporidian infection, Haemoproteus, was significantly higher in continuous forest than in habitat fragments. Further, we found that ecological traits such as diet, foraging height, habitat specialisation and distributional ranges were significantly associated with blood-borne infections. PMID:24124541

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

    PubMed

    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. PMID:27016757

  8. High throughput ranking of recombinant avian scFv antibody fragments from crude lysates using the Biacore A100.

    PubMed

    Leonard, Paul; Säfsten, Pär; Hearty, Stephen; McDonnell, Barry; Finlay, William; O'Kennedy, Richard

    2007-06-30

    Advances in molecular evolution strategies have made it possible to identify antibodies with exquisite specificities and also to fine-tune their biophysical properties for practically any specified application. Depending on the desired function, antibody/antigen interactions can be long-lived or short-lived and, therefore, particular attention is needed when seeking to identify antibodies with specific reaction-rate and affinity properties. Surface plasmon resonance (SPR) biosensors routinely generate sensitive and reliable kinetic data from antibody/antigen interactions for both therapeutic and diagnostic applications. However, many kinetic-based screening assays require rigorous sample preparation and purification prior to analysis. To ameliorate this problem, we developed a rapid and reliable assay for characterising recombinant scFv antibody fragments, directly from crude bacterial lysates. Ninety-six scFv antibodies derived from chickens immunised with C-reactive protein (CRP) were selected by phage display and evaluated using the Biacore A100 protein interaction array system. Antibodies were captured from crude bacterial extracts on the sensor chip surface and ranked based on the percentage of the complex left (% left) after dissociation in buffer. Kinetic rate constants (k(a) and k(d)) and affinity (K(D)) data were obtained for six clones that bound monomeric CRP across a broad affinity range (2.54 x 10(-8) to 3.53 x 10(-10) M). Using this assay format the A100 biosensor yielded high quality kinetic data, permitting the screening of nearly 400 antibody clones per day. PMID:17532001

  9. Mitochondrial restriction fragment length polymorphism (RFLP) and sequence variation among closely related avian species and the genetic characterization of hybrid Dendroica warblers.

    PubMed

    Lovette, I J; Bermingham, E; Rohwer, S; Wood, C

    1999-09-01

    To address several interconnected goals, we used mitochondrial DNA (mtDNA) sequences to explore evolutionary relationships among four potentially hybridizing taxa in a North American avian superspecies (Dendroica occidentalis, D. townsendi, D. virens, and D. nigrescens). We first compared the results of a previous restriction fragment length polymorphism (RFLP)-based study with 1453 nucleotides from the mitochondrial cytochrome oxidase subunit I (COI), ATP-synthase 6 (ATPase 6), and ATP-synthase 8 (ATPase 8) genes. Separate phylogenetic analyses of the RFLP and sequence data provided identical and well-supported hierarchical species-level reconstructions that grouped occidentalis and townsendi as sister taxa. We then explored several general features of mitochondrial evolution via a comparison of the RFLP and sequence data sets. Qualitative rate differences that seemed evident in highly autocorrelated comparisons of RFLP vs. sequence pairwise distances were not supported when autocorrelation was removed. We also noted a high variance in corresponding RFLP and sequence distances after the removal of autocorrelation effects. This variance suggests that caution should be used when combining RFLP and sequence-based data in studies that require the large-scale synthesis of divergence estimates drawn from sources employing different molecular techniques. Finally, we used our parallel RFLP and sequence data to design and validate a rapid and inexpensive polymerase chain reaction-RFLP (PCR-RFLP) protocol for determining species-specific mitochondrial haplotypes. This PCR-RFLP technique will be applied in ongoing studies of the occidentalis/townsendi hybrid zone, where the historic and geographical complexity of the interbreeding populations necessitates the genotyping of thousands of individual warblers. PMID:10564448

  10. Avian Astrovirus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian astroviruses comprise a diverse group of viruses affecting many avian species and causing enteritis, hepatitis and nephritis. To date, six different astroviruses have been identified in avian species based on the species of origin and viral genome characteristics: two turkey-origin astroviru...

  11. Avian influenza

    MedlinePlus

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

  12. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is a viral infection of birds that varies in severity from asymptomatic infections to mild respiratory and reproductive diseases to an acute, highly fatal systemic disease of chickens, turkeys, guinea fowls, and other avian species. Avian influenza viruses are divided into two ...

  13. Avian Metapneumoviruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  14. Avian Influenza

    MedlinePlus

    ... infectious viral disease of birds. Most avian influenza viruses do not infect humans; however some, such as ... often causing no apparent signs of illness. AI viruses can sometimes spread to domestic poultry and cause ...

  15. Avian Wings

    NASA Technical Reports Server (NTRS)

    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.

  16. Avian Flu

    SciTech Connect

    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.

  17. Avian botulism

    USGS Publications Warehouse

    Friend, Milton; Locke, Louis N.; Kennelly, James J.

    1985-01-01

    What is avian botulism? Avian botulism, or Western duck sickness, is one of the three most important disease problems of wild migratory birds. Each year, many birds are paralyzed or die after exposure to a toxin produced by the botulinum bacterium. Two of the seven toxin types that have been identifies cause mortality in wild birds; one of these types, type C, is most often associated with dieoffs of ducks, while type E primarily affects gulls and loons.

  18. Characterization of western European field isolates and vaccine strains of avian infectious laryngotracheitis virus by restriction fragment length polymorphism and sequence analysis.

    PubMed

    Neff, C; Sudler, C; Hoop, R K

    2008-06-01

    Infectious laryngotracheitis is a dramatic disease of the upper respiratory tract in poultry caused by a herpesvirus. In this study we investigated the characteristics of western European field isolates of infectious laryngotracheitis virus (ILTV) to gain more information on their diversity. The examined 104 isolates, collected from acute outbreaks during the last 35 years, originated from eight different countries: Switzerland (48), Germany (21), Sweden (14), the United Kingdom (9), Italy (5), Belgium (4), Austria (2), and Norway (1). Two vaccines, a chicken embryo origin product and a tissue culture origin product, were included in the survey. Polymerase chain reaction (PCR) was performed to amplify a 2.1-kb DNA fragment of ILTV using primers generated for the thymidine kinase (TK) gene. After digestion of the resulting PCR products by restriction endonuclease HaeIII, restriction fragment length polymorphism analysis was carried out. PCR amplicons of three field isolates and both vaccine strains were selected for sequencing. Here 98 field isolates showed the same cleavage pattern and were identical to both vaccine strains (clone 1). They differed from five Swiss isolates with identical cleavage pattern (clone 2) and one Swedish isolate (clone 3). The present study demonstrated that at least three clones of ILTV have been circulating in western Europe during the last 35 years. The 104 isolates analyzed showed a high genetic similarity regarding the TK gene, and a large majority of the field isolates (98/104) were genetically related to the vaccine strains. PMID:18646457

  19. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  20. AVIAN INFLUENZA

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. AVIAN IMMUNOTOXICOLOGY

    EPA Science Inventory

    Methods for studying the avian immune system have matured during the past two decades, with laboratory studies predominating in earlier years and field studies being conducted only in the past decade. One application has been to determine the potential for environmental contamina...

  2. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host for avian influenza virus (AIV) is in wild birds, including ducks, gulls, and shorebirds, where the virus causes primarily an enteric infection with little disease. However, AIV can infect a wide variety of host species, and with a certain level of adaptation for the aberrant host ...

  3. Avian Influenza.

    PubMed

    Zeitlin, Gary Adam; Maslow, Melanie Jane

    2005-05-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur. PMID:15847721

  4. Avian influenza.

    PubMed

    Zeitlin, Gary A; Maslow, Melanie J

    2006-03-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004 alone, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate over 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantines, and disinfection. To prepare for and prevent increased human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short, interfering RNAs and new vaccine strategies that use plasmid-based genetic systems offer promise, should a pandemic occur. PMID:16566867

  5. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  6. Other avian paramyxovirus infections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian paramyxovirus infections have been reported for chickens and turkeys in association with respiratory disease or drops in egg production. This book chapter provides general information on etiology, clinical signs, lesions, diagnosis, prevention and control of avian paramyxoviruses except Newca...

  7. Other avian paramyxoviruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian paramyxovirus infections have been reported for chickens and turkeys in association with respiratory disease or drops in egg production. This book chapter provides general information on etiology, clinical signs, lesions, diagnosis, prevention and control of avian paramyxoviruses except Newcas...

  8. Avian Influenza (Bird Flu)

    MedlinePlus

    ... this page: About CDC.gov . Avian Influenza H5 Viruses in the United States Updates and Publications Information ... Humans Examples of Human Infections with Avian Influenza Viruses Outbreaks Health Care and Laboratorian Guidance HPAI A ...

  9. Avian respiratory system disorders

    USGS Publications Warehouse

    Olsen, G.H.

    1989-01-01

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

  10. Avian Fact Sheet

    SciTech Connect

    NWCC Wildlife Work Group

    2004-12-01

    OAK-B135 After conducting four national research meetings, producing a document guiding research: Metrics and Methods for Determining or Monitoring Potential Impacts on Birds at Existing and Proposed Wind Energy Sites, 1999, and another paper, Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States, 2001, the subcommittee recognized a need to summarize in a short fact sheet what is known about avian-wind interaction and what questions remain. This fact sheet attempts to summarize in lay terms the result of extensive discussion about avian-wind interaction on land. This fact sheet does not address research conducted on offshore development. This fact sheet is not intended as a conclusion on the subject; rather, it is a summary as of Fall/Winter 2002.

  11. Avian Influenza in Birds

    MedlinePlus

    ... and even kill certain domesticated bird species including chickens, ducks, and turkeys. Infected birds can shed avian ... virus’ ability to cause disease and mortality in chickens in a laboratory setting [2.5 MB, 64 ...

  12. Global phylogeographic limits of Hawaii's avian malaria

    USGS Publications Warehouse

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

    2006-01-01

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

  13. Magma Fragmentation

    NASA Astrophysics Data System (ADS)

    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.

  14. The avian heterophil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heterophils play an indispensable role in the immune defense of the avian host. To accomplish this defense, heterophils use sophisticated mechanisms to both detect and destroy pathogenic microbes. Detection of pathogens through toll-like receptors (TLR), FC and complement receptors, and other path...

  15. Avian influenza: recent developments.

    PubMed

    Capua, Ilaria; Alexander, Dennis J

    2004-08-01

    This paper reviews the worldwide situation regarding avian influenza infections in poultry from 1997 to March 2004. The increase in the number of primary introductions and the scientific data available on the molecular basis of pathogenicity have generated concerns particularly for legislative purposes and for international trade. This has led to a new proposed definition of 'avian influenza' to extend all infections caused by H5 and H7 viruses regardless of their virulence as notifiable diseases, although this has encountered some difficulties in being approved. The paper also reviews the major outbreaks caused by viruses of the H5 or H7 subtype and the control measures applied. The zoonotic aspects of avian influenza, which until 1997 were considered to be of limited relevance in human medicine, are also discussed. 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 reassortant virus that could give rise to the next human influenza pandemic. PMID:15370036

  16. Avian influenza (fowl plague)

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  17. Avian dark cells

    NASA Technical Reports Server (NTRS)

    Hara, J.; Plymale, D. R.; Shepard, D. L.; Hara, H.; Garry, Robert F.; Yoshihara, T.; Zenner, Hans-Peter; Bolton, M.; Kalkeri, R.; Fermin, Cesar D.

    2002-01-01

    Dark cells (DCs) of mammalian and non-mammalian species help to maintain the homeostasis of the inner ear fluids in vivo. Although the avian cochlea is straight and the mammalian cochlea is coiled, no significant difference in the morphology and/or function of mammalian and avian DCs has been reported. The mammalian equivalent of avian DCs are marginal cells and are located in the stria vascularis along a bony sheet. Avian DCs hang free from the tegmentum vasculosum (TV) of the avian lagena between the perilymph and endolymph. Frame averaging was used to image the fluorescence emitted by several fluorochromes applied to freshly isolated dark cells (iDCs) from chickens (Gallus domesticus) inner ears. The viability of iDCs was monitored via trypan blue exclusion at each isolation step. Sodium Green, BCECF-AM, Rhodamine 123 and 9-anthroyl ouabain molecules were used to test iDC function. These fluorochromes label iDCs ionic transmembrane trafficking function, membrane electrogenic potentials and Na+/K+ ATPase pump's activity. Na+/K+ ATPase pump sites, were also evaluated by the p-nitrophenyl phosphatase reaction. These results suggest that iDCs remain viable for several hours after isolation without special culturing requirements and that the number and functional activity of Na+/K+ ATPase pumps in the iDCs were indistinguishable from in vivo DCs. Primary cultures of freshly iDCs were successfully maintained for 28 days in plastic dishes with RPMI 1640 culture medium. The preparation of iDCs overcomes the difficulty of DCs accessability in vivo and the unavoidable contamination that rupturing the inner ear microenvironments induces.

  18. Forest Fragmentation

    EPA Science Inventory

    This indicator describes forest fragmentation in the contiguous United States circa 2001. This information provides a broad, recent picture of the spatial pattern of the nation’s forests and the extent to which they are being broken into smaller patches and pierced or interspe...

  19. Avian flu: pandemic preparedness.

    PubMed

    Jan, Karen

    2007-01-01

    Pandemic influenza is unpredictable, and the risk of an avian flu outbreak is unclear. It is critical that home health providers, who may become overburdened quickly in the event of a pandemic outbreak, be prepared to ensure a sustainable healthcare response. This article offers information on strategies that may be used by home health providers to prepare for, prevent, and manage pandemic influenza. PMID:17984642

  20. Pathobiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus causes serious disease in a wide variety of birds and mammals. Its natural hosts are wild aquatic birds, in which most infections are unapparent. Avian Influenza (AI) viruses are classified into 16 hemagglutinin (H1-16) and nine neuraminidase (N1-9) subtypes. Each virus has on...

  1. Avian influenza prevention and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza is one of the most important diseases affecting the poultry industry around the world. Avian Influenza virus (AIV) has a broad host range in birds and mammals, although the natural reservoir is considered to be in wild birds where it typically causes an asymptomatic to mild infectio...

  2. Avian influenza: Vaccination and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Avian influenza vaccination and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Vaccination with high quality efficacious vaccines that are properly delivered can contribute to the control of avian AI outbreaks when used as part of a compr...

  4. Perturbative fragmentation

    SciTech Connect

    Kopeliovich, B. Z.; Pirner, H.-J.; Potashnikova, I. K.; Schmidt, Ivan; Tarasov, A. V.

    2008-03-01

    The Berger model of perturbative fragmentation of quarks to pions is improved by providing an absolute normalization and keeping all terms in a (1-z) expansion, which makes the calculation valid at all values of fractional pion momentum z. We also replace the nonrelativistic wave function of a loosely bound pion by the more realistic procedure of projecting to the light-cone pion wave function, which in turn is taken from well known models. The full calculation does not confirm the (1-z){sup 2} behavior of the fragmentation function (FF) predicted in [E. L. Berger, Z. Phys. C 4, 289 (1980); Phys. Lett. 89B, 241 (1980] for z>0.5, and only works at very large z>0.95, where it is in reasonable agreement with phenomenological FFs. Otherwise, we observe quite a different z-dependence which grossly underestimates data at smaller z. The disagreement is reduced after the addition of pions from decays of light vector mesons, but still remains considerable. The process dependent higher twist terms are also calculated exactly and found to be important at large z and/or p{sub T}.

  5. Avian influenza in Mexico.

    PubMed

    Villarreal, C

    2009-04-01

    The outbreak of highly pathogenic avian influenza (HPAI) H5N2 in Mexico in 1994 led to a clear increase in biosecurity measures and improvement of intensive poultry production systems. The control and eradication measures implemented were based on active surveillance, disease detection, depopulation of infected farms and prevention of possible contacts (identified by epidemiological investigations), improvement of biosecurity measures, and restriction of the movement of live birds, poultry products, by-products and infected material. In addition, Mexico introduced a massive vaccination programme, which resulted in the eradication of HPAI in a relatively short time in two affected areas that had a high density of commercial poultry. PMID:19618630

  6. Avian Soft Tissue Surgery.

    PubMed

    Guzman, David Sanchez-Migallon

    2016-01-01

    Basic surgical instrumentation for avian soft tissue surgery includes soft tissue retractors, microsurgical instrumentation, surgical loupes, and head-mounted lights. Hemostasis is fundamental during the surgical procedures. The indications, approach, and complications associated with soft tissue surgeries of the integumentary (digit constriction repair, feather cyst excision, cranial wound repair, sternal wound repair, uropygial gland excision), gastrointestinal (ingluviotomy, crop biopsy, crop burn repair, celiotomy, coelomic hernia and pseudohernia repair, proventriculotomy, ventriculotomy, enterotomy, intestinal resection and anastomosis, cloacoplasty, cloacopexy), respiratory (rhinolith removal, sinusotomy, tracheotomy, tracheal resection and anastomosis, tracheostomy, pneumonectomy) and reproductive (ovocentesis, ovariectomy, salpingohysterectomy, cesarean section, orchidectomy, vasectomy, phallectomy) systems are reviewed. PMID:26611927

  7. SARS/avian coronaviruses.

    PubMed

    Monceyron Jonassen, C

    2006-01-01

    In the hunt for the aetiology of the SARS outbreak in 2003, a newly developed virus DNA micro-array was successfully used to hybridise PCR products obtained by random amplification of nucleic acids extracted from a cell culture infected with material from a SARS patient. The SARS agent was found to hybridise with micro-array probes from both coronaviruses and astroviruses, but one of the coronavirus probes and the four astrovirus probes contained redundant sequences, spanning a highly conserved motif, named s2m, found at the 3' end of the genomes of almost all astroviruses, one picornavirus, and the poultry coronaviruses. The three other coronavirus probes, that hybridised with the SARS agent, were located in the replicase gene, and it could be concluded that the SARS agent was a novel coronavirus, harbouring s2m. The presence of this motif in different virus families is probably the result of recombinations between unrelated viruses, but its presence in both poultry and SARS coronaviruses could suggest a bird involvement in the history of the SARS coronavirus. A recent screening of wild birds for the presence of coronaviruses, using a pan-coronavirus RT-PCR, led to the identification of novel coronaviruses in the three species studied. Phylogenetic analyses performed on both replicase gene and nucleocapsid protein could not add support to a close relationship between avian and SARS coronaviruses, but all the novel avian coronaviruses were found to harbour s2m. The motif is inserted at a homologous place in avian and SARS coronavirus genomes, but in a somewhat different context for the SARS coronavirus. If the presence of s2m in these viruses is a result of two separate recombination events, this suggests that its particular position in these genomes is the only one that would not be deleterious for coronaviral replication, or that it is the result of a copy-choice recombination between coronaviruses, following an ancestral introduction in the coronavirus family by

  8. The Avian Development Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

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

  9. Avian psychology and communication.

    PubMed Central

    Rowe, Candy; Skelhorn, John

    2004-01-01

    The evolution of animal communication is a complex issue and one that attracts much research and debate. 'Receiver psychology' has been highlighted as a potential selective force, and we review how avian psychological processes and biases can influence the evolution and design of signals as well as the progress that has been made in testing these ideas in behavioural studies. Interestingly, although birds are a focal group for experimental psychologists and behavioural ecologists alike, the integration of theoretical ideas from psychology into studies of communication has been relatively slow. However, recent operant experiments are starting to address how birds perceive and respond to complex natural signals in an attempt to answer evolutionary problems in communication. This review outlines how a psychological approach to understanding communication is useful, and we hope that it stimulates further research addressing the role of psychological mechanisms in signal evolution. PMID:15306314

  10. Thromboelastography in Selected Avian Species.

    PubMed

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

    2015-12-01

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

  11. Evaluating the cell mediated immune response of avian species to avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The measurement of avian cellular immunity is critical to understanding the role and regulation of avian lymphocytes following avian influenza virus infection. Although the ability to measure avian T cell responses has steadily increased over the last few years, few studies have examined the role o...

  12. Avian Influenza A Virus Infections in Humans

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Españ ...

  13. Disappearance of insectivorous birds from tropical forest fragments

    PubMed Central

    Şekercioḡlu, Çaḡan H.; Ehrlich, Paul R.; Daily, Gretchen C.; Aygen, Deniz; Goehring, David; Sandí, Randi F.

    2002-01-01

    Determining the impact of forest disturbance and fragmentation on tropical biotas is a central goal of conservation biology. Among tropical forest birds, understory insectivores are particularly sensitive to habitat disturbance and fragmentation, despite their relatively small sizes and freedom from hunting pressure. Why these birds are especially vulnerable to fragmentation is not known. Our data indicate that the best determinant of the persistence of understory insectivorous birds in small fragments is the ability to disperse through deforested countryside habitats. This finding contradicts our initial hypothesis that the decline of insectivorous birds in forest fragments is caused by impoverished invertebrate prey base in fragments. Although we observed significantly fewer insectivorous birds in smaller fragments, extensive sampling of invertebrate communities (106,082 individuals) and avian diets (of 735 birds) revealed no important differences between large and small fragments. Neither habitat specificity nor drier fragment microclimates seemed critical. Bird species that were less affected by forest fragmentation were, in general, those that used the deforested countryside more, and we suggest that the key to their conservation will be found there. PMID:11782549

  14. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056... 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...

  15. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ... Inspection Service 9 CFR Parts 93, 94, and 95 RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal... products from regions where any subtype of highly pathogenic avian influenza is considered to exist. The... vaccinated for certain types of avian influenza, or that have moved through regions where any subtype...

  16. Markov Chain Estimation of Avian Seasonal Fecundity

    EPA Science Inventory

    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...

  17. A brief introduction to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is caused by a type A influenza virus isolated from and adapted to an avian host. This chapter covers the basic physicochemical aspects of AIV including; virus family and properties, subtype classification; basic molecular biology and genetics. The avian host range and ecology...

  18. Avian infectious laryngotracheitis.

    PubMed

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

    2000-08-01

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

  19. Avian influenza virus in pregnancy.

    PubMed

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

    2016-07-01

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

  20. Avian reproductive physiology

    USGS Publications Warehouse

    Gee, G.F.

    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

  1. Interspersion of sequences in avian myeloblastosis virus rna that rapidly hybridize with leukemic chicken cell DNA.

    PubMed Central

    Drohan, W N; Shoyab, M; Wall, R; Baluda, M A

    1975-01-01

    Liquid hybridization of progressively smaller fragments (35S, 27S, 15.5S, 12.5S, and 8S) of poly(A)-selected avian myeloblastosis virus RNA with excess DNA from leukemic chicken myeloblasts revealed that all sizes of RNA contained sequences complementary to both slowly and rapidly hybridizing cellular DNA sequences. Apparently, the RNA sequences which hybridize rapidly with excesses of cellular DNA are not restricted to any one region of the avian myeloblastosis virus 35S RNA. Instead, they appear to be randomly distributed over the entire 35S avian myeloblastosis virus RNA molecule with some positioned within 200 nucleotides of the poly(A) tract at the 3' end of the RNA. PMID:163372

  2. Reverse genetics of avian metapneumoviruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Avian metapneumovirus in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  5. Laser Cleaning of Avian Eggshell

    NASA Astrophysics Data System (ADS)

    Cornish, L.; Ball, A.; Russell, D.

    A low vacuum SEM was used to evaluate the effect of using an Nd:YAG laser as a non-contact technique for cleaning avian eggshells. The technique shows potential, since there are no obvious deleterious effects from cleaning, but further study is required to understand how the laser is interacting with the sample surface.

  6. Molecular characterization of avian astroviruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Astroviruses are frequently associated with enteric diseases in poultry, being isolated from cases of runting-stunting syndrome (RSS) of broiler chickens, poult enteritis complex (PEC) and poult enteritis mortality syndrome (PEMS) of turkeys. Currently, five types of avian astrovirus have been ident...

  7. Avian Influenza: Our current understanding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) has become one of the most important diseases of the poultry industry around the world. The virus has a broad host range in birds and mammals, although the natural reservoir is considered to be in wild birds where it typically causes an asymptomatic to mild infection. T...

  8. Influenza vaccines for avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  9. Genomic organization of the crested ibis MHC provides new insight into ancestral avian MHC structure

    PubMed Central

    Chen, Li-Cheng; Lan, Hong; Sun, Li; Deng, Yan-Li; Tang, Ke-Yi; Wan, Qiu-Hong

    2015-01-01

    The major histocompatibility complex (MHC) plays an important role in immune response. Avian MHCs are not well characterized, only reporting highly compact Galliformes MHCs and extensively fragmented zebra finch MHC. We report the first genomic structure of an endangered Pelecaniformes (crested ibis) MHC containing 54 genes in three regions spanning ~500 kb. In contrast to the loose BG (26 loci within 265 kb) and Class I (11 within 150) genomic structures, the Core Region is condensed (17 within 85). Furthermore, this Region exhibits a COL11A2 gene, followed by four tandem MHC class II αβ dyads retaining two suites of anciently duplicated “αβ” lineages. Thus, the crested ibis MHC structure is entirely different from the known avian MHC architectures but similar to that of mammalian MHCs, suggesting that the fundamental structure of ancestral avian class II MHCs should be “COL11A2-IIαβ1-IIαβ2.” The gene structures, residue characteristics, and expression levels of the five class I genes reveal inter-locus functional divergence. However, phylogenetic analysis indicates that these five genes generate a well-supported intra-species clade, showing evidence for recent duplications. Our analyses suggest dramatic structural variation among avian MHC lineages, help elucidate avian MHC evolution, and provide a foundation for future conservation studies. PMID:25608659

  10. Avian disease at the Salton Sea

    USGS Publications Warehouse

    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

  11. Selectable fragmentation warhead

    DOEpatents

    Bryan, Courtney S.; Paisley, Dennis L.; Montoya, Nelson I.; Stahl, David B.

    1993-01-01

    A selectable fragmentation warhead capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.

  12. Selectable fragmentation warhead

    SciTech Connect

    Bryan, C.S.; Paisley, D.L.; Montoya, N.I.; Stahl, D.B.

    1992-12-31

    This report discusses a selectable fragmentation warhead which is capable of producing a predetermined number of fragments from a metal plate, and accelerating the fragments toward a target. A first explosive located adjacent to the plate is detonated at selected number of points by laser-driven slapper detonators. In one embodiment, a smoother-disk and a second explosive, located adjacent to the first explosive, serve to increase acceleration of the fragments toward a target. The ability to produce a selected number of fragments allows for effective destruction of a chosen target.

  13. Gender determination of avian embryo

    DOEpatents

    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.

  14. Avian malaria in New Zealand.

    PubMed

    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. PMID:24313228

  15. Avian influenza: the Canadian experience.

    PubMed

    Pasick, J; Berhane, Y; Hooper-McGrevy, K

    2009-04-01

    Reports of sporadic avian influenza outbreaks involving domestic poultry date back to the 1960s. With the exception of A/turkey/Ontario/7732/1966 (H5N9), which was isolated from a turkey breeding establishment, all viruses characterised prior to 2004 fit the criteria of low pathogenic avian influenza (LPAI). Only in retrospect was A/turkey/Ontario/7732/1966 shown to meet the criteria of a highly pathogenic avian influenza (HPAI). In 2004, Canada reported its first case of HPAI to the World Organisation for Animal Health (OIE). The outbreak, which began in a broiler breeder farm in the Fraser Valley of British Columbia, involved an H7N3 LPAI virus which underwent a sudden virulence shift to HPAI. More than 17 million birds were culled and CAN$380 million in gross economic costs incurred before the outbreak was eventually brought under control. In its aftermath a number of changes were implemented to mitigate the impact of any future HPAI outbreaks. These changes involved various aspects of avian influenza detection and control, including self-quarantine, biosecurity, surveillance, and laboratory testing. In 2005, a national surveillance programme for influenza A viruses in wild birds was initiated. Results of this survey provided evidence for wild birds as the likely source of an H5N2 LPAI outbreak that occurred in domestic ducks in the Fraser Valley in the autumn of 2005. Wild birds were once again implicated in an H7N3 HPAI outbreak involving a broiler breeder operation in Saskatchewan in 2007. Fortunately, both of these outbreaks were limited in extent, a consequence of some of the changes implemented in response to the 2004 British Columbia outbreak. PMID:19618638

  16. Avian embryos in hypoxic environments.

    PubMed

    León-Velarde, F; Monge-C, C

    2004-08-12

    Avian embryos at high altitude do not benefit of the maternal protection against hypoxia as in mammals. Nevertheless, avian embryos are known to hatch successfully at altitudes between 4,000 and 6,500 m. This review considers some of the processes that bring about the outstanding modifications in the pressure differences between the environment and mitochondria of avian embryos in hypoxic environments. Among species, some maintain normal levels of oxygen consumption ( VO2) have a high oxygen carrying capacity, lower the air cell-arterial pressure difference ( PAO2 - PaO2 ) with a constant pH. Other species decrease VO2, increase only slightly the oxygen carrying capacity, have a higher PAO2 - PaO2 difference than sea-level embryos and lower the PCO2 and pH. High altitude embryos, and those exposed to hypoxia have an accelerated decline of erythrocyte ATP levels during development and an earlier stimulation of 2,3-BPG synthesis. A higher Bohr effect may ensure high tissue PO2 in the presence of the high-affinity hemoglobin. Independently of the strategy used, they serve together to promote suitable rates of development and successful hatching of high altitude birds in hypoxic environments. PMID:15288603

  17. Avian utilization of subsidence wetlands

    SciTech Connect

    Nawrot, J.R.; Conley, P.S.; Smout, C.L.

    1995-09-01

    Diverse and productive wetlands have resulted from coal mining in the midwest. The trend from surface to underground mining has increased the potential for subsidence. Planned subsidence of longwall mining areas provides increased opportunities for wetland habitat establishment. Planned subsidence over a 180 meter (590 foot) deep longwall mine in southern Illinois during 1984 to 1986 produced three subsidence wetlands totaling 15 hectares (38 acres). The resulting palustrine emergent wetlands enhanced habitat diversity within the surrounding palustrine forested unsubsided area. Habitat assessments and evaluations of avian utilization of the subsidence wetlands were conducted during February 1990 through October 1991. Avian utilization was greatest within the subsided wetlands. Fifty-three bird species representing seven foraging guilds utilized the subsidence wetlands. Wading/fishing, dabbling waterfowl, and insectivorous avian guilds dominated the subsidence wetlands. The subsidence wetlands represented ideal habitat for wood ducks and great blue herons which utilized snags adjacent to and within the wetlands for nesting (19 great blue heron nests produced 25 young). Dense cover and a rich supply of macroinvertebrates provide excellent brood habitat for wood ducks, while herpetofauna and ichthyofauna provided abundant forage in shallow water zones for great blue herons and other wetland wading birds. The diversity of game and non-game avifauna utilizing the subsidence areas demonstrated the unique value of these wetlands. Preplanned subsidence wetlands can help mitigate loss of wetland habitats in the midwest.

  18. Universality of fragment shapes.

    PubMed

    Domokos, Gábor; Kun, Ferenc; Sipos, András Árpád; Szabó, Tímea

    2015-01-01

    The shape of fragments generated by the breakup of solids is central to a wide variety of problems ranging from the geomorphic evolution of boulders to the accumulation of space debris orbiting Earth. Although the statistics of the mass of fragments has been found to show a universal scaling behavior, the comprehensive characterization of fragment shapes still remained a fundamental challenge. We performed a thorough experimental study of the problem fragmenting various types of materials by slowly proceeding weathering and by rapid breakup due to explosion and hammering. We demonstrate that the shape of fragments obeys an astonishing universality having the same generic evolution with the fragment size irrespective of materials details and loading conditions. There exists a cutoff size below which fragments have an isotropic shape, however, as the size increases an exponential convergence is obtained to a unique elongated form. We show that a discrete stochastic model of fragmentation reproduces both the size and shape of fragments tuning only a single parameter which strengthens the general validity of the scaling laws. The dependence of the probability of the crack plan orientation on the linear extension of fragments proved to be essential for the shape selection mechanism. PMID:25772300

  19. Universality of fragment shapes

    PubMed Central

    Domokos, Gábor; Kun, Ferenc; Sipos, András Árpád; Szabó, Tímea

    2015-01-01

    The shape of fragments generated by the breakup of solids is central to a wide variety of problems ranging from the geomorphic evolution of boulders to the accumulation of space debris orbiting Earth. Although the statistics of the mass of fragments has been found to show a universal scaling behavior, the comprehensive characterization of fragment shapes still remained a fundamental challenge. We performed a thorough experimental study of the problem fragmenting various types of materials by slowly proceeding weathering and by rapid breakup due to explosion and hammering. We demonstrate that the shape of fragments obeys an astonishing universality having the same generic evolution with the fragment size irrespective of materials details and loading conditions. There exists a cutoff size below which fragments have an isotropic shape, however, as the size increases an exponential convergence is obtained to a unique elongated form. We show that a discrete stochastic model of fragmentation reproduces both the size and shape of fragments tuning only a single parameter which strengthens the general validity of the scaling laws. The dependence of the probability of the crack plan orientation on the linear extension of fragments proved to be essential for the shape selection mechanism. PMID:25772300

  20. Universality of fragment shapes

    NASA Astrophysics Data System (ADS)

    Domokos, Gábor; Kun, Ferenc; Sipos, András Árpád; Szabó, Tímea

    2015-03-01

    The shape of fragments generated by the breakup of solids is central to a wide variety of problems ranging from the geomorphic evolution of boulders to the accumulation of space debris orbiting Earth. Although the statistics of the mass of fragments has been found to show a universal scaling behavior, the comprehensive characterization of fragment shapes still remained a fundamental challenge. We performed a thorough experimental study of the problem fragmenting various types of materials by slowly proceeding weathering and by rapid breakup due to explosion and hammering. We demonstrate that the shape of fragments obeys an astonishing universality having the same generic evolution with the fragment size irrespective of materials details and loading conditions. There exists a cutoff size below which fragments have an isotropic shape, however, as the size increases an exponential convergence is obtained to a unique elongated form. We show that a discrete stochastic model of fragmentation reproduces both the size and shape of fragments tuning only a single parameter which strengthens the general validity of the scaling laws. The dependence of the probability of the crack plan orientation on the linear extension of fragments proved to be essential for the shape selection mechanism.

  1. Fragmentation properties of metals

    SciTech Connect

    Grady, D.E.; Kipp, M.E.

    1996-06-01

    In the present study we are developing an experimental fracture material property test method specific to dynamic fragmentation. Spherical test samples of the metals of interest are subjected to controlled impulsive stress loads by acceleration to high velocities with a light-gas launcher facility and subsequent normal impact on thin plates. Motion, deformation and fragmentation of the test samples are diagnosed with multiple flash radiography methods. The impact plate materials are selected to be transparent to the x-ray method so that only test metal material is imaged. Through a systematic series of such tests, both strain-to-failure and fragmentation resistance properties are determined through this experimental method. Fragmentation property data for several steels, copper, aluminum, tantalum and titanium have been obtained to date. Aspects of the dynamic data have been analyzed with computational methods to achieve a better understanding of the processes leading to failure and fragmentation, and to test an existing computational fragmentation model.

  2. 76 FR 4046 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-24

    ...We are amending the regulations concerning the importation of animals and animal products to prohibit or restrict the importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza is considered to exist. We are also adding restrictions concerning importation of live poultry and birds that have been vaccinated for certain types of avian influenza,......

  3. The global nature of avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus is a global virus which knows no geographic boundaries, has no political agenda, and can infect poultry irrespective of their agricultural or anthropocentric production systems. Avian influenza viruses or evidence of their infection have been detected in poultry and wild birds...

  4. Biology and transmission of avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host and reservoir for avian influenza is in wild birds where the viral infection is typically asymptomatic. The virus primarily replicates in the enteric tract and transmission is thought to be primarily by fecal-oral transmission. Avian influenza can infect a broad host range, but fo...

  5. Avian influenza diagnostics and surveillance methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The clinical presentation of avian influenza (AI) varies by virus strain and host species. The clinical disease and lesions the virus produces in poultry are not pathognomonic for avian influenza; therefore, diagnosis of AI virus (AIV) infection requires a laboratory test. Detection of AIV infecti...

  6. Avian influenza biology and disease transmission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host and reservoir for avian influenza is in wild birds where the viral infection is typically asymptomatic. The virus primarily replicates in the enteric tract and transmission is thought to be primarily by fecal oral transmission. Avian influenza can infect a broad host range, but fo...

  7. Avian influenza: preparedness and response strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus is naturally found in wild birds, primarily waterfowl, but the virus may also be found in poultry. In the United States we have a strong passive and active surveillance program for avian influenza in poultry. This includes serologic testing on most flocks that go through the ...

  8. A brief introduction to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) causes a disease of high economic importance for poultry production worldwide. The earliest recorded cases of probable high pathogenicity AIV in poultry were reported in Italy in the 1870’s and avian influenza been recognized in domestic poultry through the modern era of ...

  9. DIVA vaccination strategies for avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccination for both low pathogenic and highly pathogenic avian influenza is commonly used for countries that have been endemic for avian influenza influenza virus, but stamping out policies are common for countries that are normally free of the disease. Stamping out policies of euthanizing infecte...

  10. MANAGING AVIAN FLU, CARCASS MANAGEMENT & BIOSOLIDS

    EPA Science Inventory

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

  11. Cryoconservation of avian gonads in Canada.

    PubMed

    Silversides, F G; Robertson, M C; Liu, J

    2013-10-01

    Avian genetic resources have declined dramatically over the past half century as the cost of maintaining populations has exceeded the perceived benefit of keeping them. Despite the early importance of poultry in the development of cryopreservation techniques, very little avian germplasm has been conserved. Cryopreservation and recovery of avian gonads preserve the W chromosome and overcome problems of freezing and recovering semen or conserving and manipulating embryonic cells, and the use of vitrification procedures for preserving gonads minimizes cellular damage. On the basis of research demonstrating the biological possibility of cryopreserving and transplanting avian gonads, 5,125 testicles and 2,667 ovaries from 10 populations of Japanese quail, 9 populations of chickens, and 1 population of Chilean tinamou were cryopreserved and sent to the Canadian Animal Genetic Resources program for long-term storage. These gonads represent 20 of the 33 distinct avian populations currently maintained at Canadian public institutions of agricultural research. PMID:24046407

  12. Optimized polypeptide for a subunit vaccine against avian reovirus.

    PubMed

    Goldenberg, Dana; Lublin, Avishai; Rosenbluth, Ezra; Heller, E Dan; Pitcovski, Jacob

    2016-06-01

    Avian reovirus (ARV) is a disease-causing agent. The disease is prevented by vaccination with a genotype-specific vaccine while many variants of ARV exist in the field worldwide. Production of new attenuated vaccines is a long-term process and in the case of fast-mutating viruses, an impractical one. In the era of molecular biology, vaccines may be produced by using only the relevant protein for induction of neutralizing antibodies, enabling fast adjustment to the emergence of new genetic strains. Sigma C (SC) protein of ARV is a homotrimer that facilitates host-cell attachment and induce the production and secretion of neutralizing antibodies. The aim of this study was to identify the region of SC that will elicit a protective immune response. Full-length (residues 1-326) and two partial fragments of SC (residues 122-326 and 192-326) were produced in Escherichia coli. The SC fragment of residues 122-326 include the globular head, shaft and hinge domains, while eliminating intra-capsular region. This fragment induces significantly higher levels of anti-ARV antibodies than the shorter fragment or full length SC, which neutralized embryos infection by the virulent strain to a higher extent compared with the antibodies produced in response to the whole virus vaccine. Residues 122-326 fragment is assumed to be folded correctly, exposing linear as well as conformational epitopes that are identical to those of the native protein, while possibly excluding suppressor sequences. The results of this study may serve for the development of a recombinant subunit vaccine for ARV. PMID:27155492

  13. Landscape matrix mediates occupancy dynamics of Neotropical avian insectivores

    USGS Publications Warehouse

    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.

  14. Influenza vaccines for avian species.

    PubMed

    Kapczynski, Darrell R; Swayne, David E

    2009-01-01

    Beginning in Southeast Asia in 2003, a multinational epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity and mortality in many bird species, was responsible for considerable economic losses via trade restrictions, and crossed species barriers (including its recovery from human cases). To date, these H5N1 HPAI viruses have been isolated in European, Middle Eastern, and African countries, and are considered endemic in many areas where regulatory control and different production sectors face substantial hurdles in controlling the spread of this disease. While control of avian influenza (AI) virus infections in wild bird populations may not be feasible at this point, control and eradiation of AI from commercial, semicommercial, zoo, pet, and village/backyard birds will be critical to preventing events that could lead to the emergence of epizootic influenza virus. Efficacious vaccines can help reduce disease, viral shedding, and transmission to susceptible cohorts. However, only when vaccines are used in a comprehensive program including biosecurity, education, culling, diagnostics and surveillance can control and eradication be considered achievable goals. In humans, protection against influenza is provided by vaccines that are chosen based on molecular, epidemiologic, and antigenic data. In poultry and other birds, AI vaccines are produced against a specific hemagglutinin subtype of AI, and use is decided by government and state agricultural authorities based on risk and economic considerations, including the potential for trade restrictions. In the current H5N1 HPAI epizootic, vaccines have been used in a variety of avian species as a part of an overall control program to aid in disease management and control. PMID:19768403

  15. Genomic Avenue to Avian Colisepticemia

    PubMed Central

    Huja, Sagi; Oren, Yaara; Trost, Eva; Brzuszkiewicz, Elzbieta; Biran, Dvora; Blom, Jochen; Goesmann, Alexander; Gottschalk, Gerhard; Hacker, Jörg

    2015-01-01

    ABSTRACT Here we present an extensive genomic and genetic analysis of Escherichia coli strains of serotype O78 that represent the major cause of avian colisepticemia, an invasive infection caused by avian pathogenic Escherichia coli (APEC) strains. It is associated with high mortality and morbidity, resulting in significant economic consequences for the poultry industry. To understand the genetic basis of the virulence of avian septicemic E. coli, we sequenced the entire genome of a clinical isolate of serotype O78—O78:H19 ST88 isolate 789 (O78-9)—and compared it with three publicly available APEC O78 sequences and one complete genome of APEC serotype O1 strain. Although there was a large variability in genome content between the APEC strains, several genes were conserved, which are potentially critical for colisepticemia. Some of these genes are present in multiple copies per genome or code for gene products with overlapping function, signifying their importance. A systematic deletion of each of these virulence-related genes identified three systems that are conserved in all septicemic strains examined and are critical for serum survival, a prerequisite for septicemia. These are the plasmid-encoded protein, the defective ETT2 (E. coli type 3 secretion system 2) type 3 secretion system ETT2sepsis, and iron uptake systems. Strain O78-9 is the only APEC O78 strain that also carried the regulon coding for yersiniabactin, the iron binding system of the Yersinia high-pathogenicity island. Interestingly, this system is the only one that cannot be complemented by other iron uptake systems under iron limitation and in serum. PMID:25587010

  16. Physiologically driven avian vocal synthesizer

    NASA Astrophysics Data System (ADS)

    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.

  17. Avian Risk and Fatality Protocol

    SciTech Connect

    Morrison, M. L.

    1998-11-12

    The protocol is designed to assist with the placement of wind power developments, and to document bird behavior and fatalities resulting from existing wind power developments. A standardized protocol will assist with comparing data among potential and existing development locations. Furthermore, this protocol is based on standard methods being used in other studies of bird behavior. The data collected will only be useful if observers follow each method carefully. In addition, the data collected using this protocol will likely be used by a permitting or other regulatory agency in evaluating the avian impacts at the site.

  18. Fragments and Coherence

    ERIC Educational Resources Information Center

    Watson, Anne

    2008-01-01

    Can teachers contact the inner coherence of mathematics while working in a context fragmented by always-new objectives, criteria, and initiatives? How, more importantly, can learners experience the inner coherence of mathematics while working in a context fragmented by testing, modular curricular, short-term learning objectives, and lessons that…

  19. Fluctuations in nuclear fragmentation

    SciTech Connect

    Aranda, A.; Dorso, C.O.; Furci, V.; Lopez, J.A.

    1995-12-01

    Heavy ion collisions can be used to study the thermodynamics of hot and dense nuclear matter only if the initial mass and energy fluctuations that lead to fragmentation are of thermal origin and survive the disassembly process. If this is the case, the observed fragment multiplicity should be directly related to those initial fluctuations and to the conditions of temperature and density causing them. The feasibility of this scenario is demonstrated with a molecular dynamics study of the evolution of mass and energy fluctuations, and fluctuations of the phase-space density. First, it is verified that the fluctuations leading to fragmentation are indeed early ones. Second, it is determined that different initial conditions of density and temperature can indeed produce varying final fragment multiplicities. The {rho}-{ital T} plane is mapped to the fragment multiplicity with good precision. This mapping should be easily reproducible with existing experimental data.

  20. Avian botulism and avian chlamydiosis in wild water birds, Benton Lake National Wildlife Refuge, Montana, USA

    USGS Publications Warehouse

    Docherty, Douglas E.; Franson, J. Christian; Brannian, Roger E.; Long, Renee R.; Radi, Craig A.; Krueger, David; Johnson, Robert F.

    2012-01-01

    In 1999, the U.S. Geological Survey (USGS) National Wildlife Health Center, Madison, Wisconsin, conducted a diagnostic investigation into a water bird mortality event involving intoxication with avian botulism type C and infection with avian chlamydiosis at the Benton Lake National Wildlife Refuge in Montana, USA. Of 24 carcasses necropsied, 11 had lesions consistent with avian chlamydiosis, including two that tested positive for infectious Chlamydophila psittaci, and 12 were positive for avian botulism type C. One bird tested positive for both avian botulism type C and C. psittaci. Of 61 apparently healthy water birds sampled and released, 13 had serologic evidence of C. psittaci infection and 7 were, at the time of capture, shedding infectious C. psittaci via the cloacal or oropharyngeal route. Since more routinely diagnosed disease conditions may mask avian chlamydiosis, these findings support the need for a comprehensive diagnostic investigation when determining the cause of a wildlife mortality event.

  1. Genetic Applications in Avian Conservation

    USGS Publications Warehouse

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

    2011-01-01

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

  2. Presence of avian bornavirus RNA and anti-avian bornavirus antibodies in apparently healthy macaws.

    PubMed

    De Kloet, Siwo R; Dorrestein, Gerry M

    2009-12-01

    Recently a novel avian bornavirus has been described that has been suggested to be the possible etiological agent for proventricular dilatation disease or macaw wasting disease. This article describes two macaws that shed avian bornaviral RNA sequences and demonstrated anti-avian bornavirus antibodies as revealed by reverse transcriptase polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blot, yet are free of outward clinical signs of the disease. PMID:20095158

  3. Opaque rock fragments

    SciTech Connect

    Abhijit, B.; Molinaroli, E.; Olsen, J.

    1987-05-01

    The authors describe a new, rare, but petrogenetically significant variety of rock fragments from Holocene detrital sediments. Approximately 50% of the opaque heavy mineral concentrates from Holocene siliciclastic sands are polymineralic-Fe-Ti oxide particles, i.e., they are opaque rock fragments. About 40% to 70% of these rock fragments show intergrowth of hm + il, mt + il, and mt + hm +/- il. Modal analysis of 23,282 opaque particles in 117 polished thin sections of granitic and metamorphic parent rocks and their daughter sands from semi-arid and humid climates show the following relative abundances. The data show that opaque rock fragments are more common in sands from igneous source rocks and that hm + il fragments are more durable. They assume that equilibrium conditions existed in parent rocks during the growth of these paired minerals, and that the Ti/Fe ratio did not change during oxidation of mt to hm. Geothermometric determinations using electron probe microanalysis of opaque rock fragments in sand samples from Lake Erie and the Adriatic Sea suggest that these rock fragments may have equilibrated at approximately 900/sup 0/ and 525/sup 0/C, respectively.

  4. Selectable fragmentation warhead

    SciTech Connect

    Bryan, C.S.; Paisley, D.L.; Montoya, N.I.; Stahl, D.B.

    1993-07-20

    A selectable fragmentation warhead is described comprising: a case having proximal and distal ends; a fragmenting plate mounted in said distal end of said casing; first explosive means cast adjacent to said fragmenting plate for creating a predetermined number of fragments from said fragmenting plate; three or more first laser-driven slapper detonators located adjacent to said first explosive means for detonating said first explosive means in a predetermined pattern; smoother-disk means located adjacent to said first means for accelerating said fragments; second explosive means cast adjacent to said smoother-disk means for further accelerating said fragments; at least one laser-driven slapper detonators located in said second explosive means; a laser located in said proximal end of said casing; optical fibers connecting said laser to said first and second laser-driven slapper detonators; and optical switch means located in series with said optical fibers connected to said plurality of first laser-driven slapper detonators for blocking or passing light from said laser to said plurality of first laser-driven slapper detonators.

  5. Stratification of gallstone fragments: the key to more effective fragmentation.

    PubMed

    Alderfer, J T; Laufer, I; Wisniewski, F; Malet, P F

    1992-04-01

    During previous experiments with in vitro fragmentation in a simulated gallbladder, we noticed that stone fragments tended to stratify with the dust and smaller fragments settled to the dependent portion, while the larger fragments settled on top. We reviewed the oral cholecystogram (OCG) of 10 patients examined 6 months following gallstone lithotripsy. In all cases with adequate visualization of stone fragments, the stratification phenomenon was observed. We hypothesized that adjusting the shock wave focus to target on these large fragments would improve the efficiency of fragmentation. To test this hypothesis, we fragmented three matched pairs of gallstones in vitro. For each pair, the stones were removed from the same gallbladder and the stone weights of the two stones were within 10%. The smaller member of each pair was fragmented using the "old method" with the focus on the fragment line. The larger stone was fragmented with the "new method" with the focus in the acoustic shadow deep to the echogenic line caused by the dust and small fragments in the dependent portion. The distribution of fragments was analyzed by passing the fragments through a series of filters. With the new method of targeting, the proportion of fragments less than 1.5 mm was doubled while the fragments greater than 5 mm were eliminated. The new method of targeting, taking into account the stratification of stone fragments, produces more effective fragmentation and should lead to more rapid clearance of fragments from the gallbladder. PMID:10149180

  6. Emerging and reemerging diseases of avian wildlife

    USGS Publications Warehouse

    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.

  7. An update on avian influenza in Mexico.

    PubMed

    Villarreal-Chávez, C; Rivera-Cruz, E

    2003-01-01

    The avian influenza high-pathogenicity virus was eradicated in poultry of Mexico in a relatively short period by the use of inactivated emulsified vaccine, enforcing biosecurity, and controlling movement of poultry and poultry products. Mexico maintains a permanent and reliable monitoring program for AI. H5N2 is the only avian influenza subtype identified. It is possible to control and eradicate the avian influenza low-pathogenicity virus mainly by controlled depopulation of positive poultry, reinforcing biosecurity, and the use of vaccines. PMID:14575101

  8. Emerging and reemerging diseases of avian wildlife.

    PubMed

    Pello, Susan J; Olsen, Glenn H

    2013-05-01

    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. PMID:23642867

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

    PubMed

    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. PMID:27010277

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

    PubMed

    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. PMID:24202734

  11. Fragment capture device

    DOEpatents

    Payne, Lloyd R.; Cole, David L.

    2010-03-30

    A fragment capture device for use in explosive containment. The device comprises an assembly of at least two rows of bars positioned to eliminate line-of-sight trajectories between the generation point of fragments and a surrounding containment vessel or asset. The device comprises an array of at least two rows of bars, wherein each row is staggered with respect to the adjacent row, and wherein a lateral dimension of each bar and a relative position of each bar in combination provides blockage of a straight-line passage of a solid fragment through the adjacent rows of bars, wherein a generation point of the solid fragment is located within a cavity at least partially enclosed by the array of bars.

  12. Fracture tooth fragment reattachment

    PubMed Central

    Maitin, Nitin; Maitin, Shipra Nangalia; Rastogi, Khushboo; Bhushan, Rajarshi

    2013-01-01

    Coronal fractures of the anterior teeth are a common form of dental trauma and its sequelae may impair the establishment and accomplishment of an adequate treatment plan. Among the various treatment options, reattachment of a crown fragment is a conservative treatment that should be considered for crown fractures of anterior teeth. This clinical case reports the management of two coronal tooth fracture cases that were successfully treated using tooth fragment reattachment using glass-fibre-reinforced composite post. PMID:23853012

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

    USGS Publications Warehouse

    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

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

    USGS Publications Warehouse

    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

  15. OBSERVATIONS ON THE AVIAN PARATYPHOID BACILLI.

    PubMed

    Mulsow, F W

    1919-07-01

    This investigator presents a detailed discussion of certain types of avian bacteria, which will be of interest to specialists. He notes some reactions not observed before and the agglutinative relations. PMID:18010130

  16. Are wetlands the reservoir for avian cholera?

    USGS Publications Warehouse

    Samuel, M.D.; Shadduck, D.J.; Goldberg, D.R.

    2004-01-01

    Wetlands have long been suspected to be an important reservoir for Pasteurella multocida and therefore the likely source of avian cholera outbreaks. During the fall of 1995a??98 we collected sediment and water samples from 44 wetlands where avian cholera epizootics occurred the previous winter or spring. We attempted to isolate P. multocida in sediment and surface water samples from 10 locations distributed throughout each wetland. We were not able to isolate P. multocida from any of the 440 water and 440 sediment samples collected from these wetlands. In contrast, during other investigations of avian cholera we isolated P. multocida from 20 of 44 wetlands, including 7% of the water and 4.5% of the sediment samples collected during or shortly following epizootic events. Our results indicate that wetlands are an unlikely reservoir for the bacteria that causes avian cholera.

  17. Avian Models in Teratology and Developmental Toxicology

    PubMed Central

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

    2015-01-01

    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. PMID:22669661

  18. Germline Modification and Engineering in Avian Species.

    PubMed

    Lee, Hong Jo; Lee, Hyung Chul; Han, Jae Yong

    2015-09-01

    Production of genome-edited animals using germline-competent cells and genetic modification tools has provided opportunities for investigation of biological mechanisms in various organisms. The recently reported programmed genome editing technology that can induce gene modification at a target locus in an efficient and precise manner facilitates establishment of animal models. In this regard, the demand for genome-edited avian species, which are some of the most suitable model animals due to their unique embryonic development, has also increased. Furthermore, germline chimera production through long-term culture of chicken primordial germ cells (PGCs) has facilitated research on production of genome-edited chickens. Thus, use of avian germline modification is promising for development of novel avian models for research of disease control and various biological mechanisms. Here, we discuss recent progress in genome modification technology in avian species and its applications and future strategies. PMID:26333275

  19. Germline Modification and Engineering in Avian Species

    PubMed Central

    Lee, Hong Jo; Lee, Hyung Chul; Han, Jae Yong

    2015-01-01

    Production of genome-edited animals using germline-competent cells and genetic modification tools has provided opportunities for investigation of biological mechanisms in various organisms. The recently reported programmed genome editing technology that can induce gene modification at a target locus in an efficient and precise manner facilitates establishment of animal models. In this regard, the demand for genome-edited avian species, which are some of the most suitable model animals due to their unique embryonic development, has also increased. Furthermore, germline chimera production through long-term culture of chicken primordial germ cells (PGCs) has facilitated research on production of genome-edited chickens. Thus, use of avian germline modification is promising for development of novel avian models for research of disease control and various biological mechanisms. Here, we discuss recent progress in genome modification technology in avian species and its applications and future strategies. PMID:26333275

  20. Ecological impacts of tropical forest fragmentation: how consistent are patterns in species richness and nestedness?

    PubMed Central

    Hill, Jane K.; Gray, Michael A.; Khen, Chey Vun; Benedick, Suzan; Tawatao, Noel; Hamer, Keith C.

    2011-01-01

    Large areas of tropical forest now exist as remnants scattered across agricultural landscapes, and so understanding the impacts of forest fragmentation is important for biodiversity conservation. We examined species richness and nestedness among tropical forest remnants in birds (meta-analysis of published studies) and insects (field data for fruit-feeding Lepidoptera (butterflies and moths) and ants). Species–area relationships were evident in all four taxa, and avian and insect assemblages in remnants typically were nested subsets of those in larger areas. Avian carnivores and nectarivores and predatory ants were more nested than other guilds, implying that the sequential loss of species was more predictable in these groups, and that fragmentation alters the trophic organization of communities. For butterflies, the ordering of fragments to achieve maximum nestedness was by fragment area, suggesting that differences among fragments were driven mainly by extinction. In contrast for moths, maximum nestedness was achieved by ordering species by wing length; species with longer wings (implying better dispersal) were more likely to occur at all sites, including low diversity sites, suggesting that differences among fragments were driven more strongly by colonization. Although all four taxa exhibited high levels of nestedness, patterns of species turnover were also idiosyncratic, and thus even species-poor sites contributed to landscape-scale biodiversity, particularly for insects. PMID:22006967

  1. Ecological impacts of tropical forest fragmentation: how consistent are patterns in species richness and nestedness?

    PubMed

    Hill, Jane K; Gray, Michael A; Khen, Chey Vun; Benedick, Suzan; Tawatao, Noel; Hamer, Keith C

    2011-11-27

    Large areas of tropical forest now exist as remnants scattered across agricultural landscapes, and so understanding the impacts of forest fragmentation is important for biodiversity conservation. We examined species richness and nestedness among tropical forest remnants in birds (meta-analysis of published studies) and insects (field data for fruit-feeding Lepidoptera (butterflies and moths) and ants). Species-area relationships were evident in all four taxa, and avian and insect assemblages in remnants typically were nested subsets of those in larger areas. Avian carnivores and nectarivores and predatory ants were more nested than other guilds, implying that the sequential loss of species was more predictable in these groups, and that fragmentation alters the trophic organization of communities. For butterflies, the ordering of fragments to achieve maximum nestedness was by fragment area, suggesting that differences among fragments were driven mainly by extinction. In contrast for moths, maximum nestedness was achieved by ordering species by wing length; species with longer wings (implying better dispersal) were more likely to occur at all sites, including low diversity sites, suggesting that differences among fragments were driven more strongly by colonization. Although all four taxa exhibited high levels of nestedness, patterns of species turnover were also idiosyncratic, and thus even species-poor sites contributed to landscape-scale biodiversity, particularly for insects. PMID:22006967

  2. Avian influenza: an emerging pandemic threat.

    PubMed

    Jin, Xian Wen; Mossad, Sherif B

    2005-12-01

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

  3. Report of the Avian Development Working Group

    NASA Technical Reports Server (NTRS)

    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.

  4. Avian study protocols and wind energy development

    SciTech Connect

    Fisher, K.

    1995-12-01

    This paper identifies the need to develop and use standardized avian study protocols to determine avian impacts at new and existing wind energy facilities. This will allow data collected from various sites to be correlated for better understanding wind energy related avian impacts. Factors contributing to an increased interest in wind energy facilities by electric utilities include: (1) Increased demand for electricity;(2) increased constraints on traditional electrical generating facilities (i.e. hydroelectric and nuclear power plants);(3) improved wind turbine technology. During the 1980`s generous tax credits spawned the development of wind energy facilities, known as wind farms, in California. Commercial scale wind farm proposals are being actively considered in states across the country - Washington, Oregon, Wyoming, Wisconsin, Texas, and Vermont to name a few. From the wind farms in California the unexpected issue of avian impacts, especially to birds-of-prey, or raptor, surfaced and continues to plague the wind industry. However, most of the avian studies did not followed a standardized protocol or methodology and, therefore, data is unavailable to analyze and compare impacts at different sites or with differing technologies and configurations. Effective mitigation can not be designed and applied until these differences are understood. The Bonneville Power Administration is using comparable avian study protocols to collect data for two environmental impact statements being prepared for two separate wind farm proposals. Similar protocol will be required for any other avian impact analysis performed by the agency on proposed or existing wind farms. The knowledge gained from these studies should contribute to a better understanding of avian interactions with wind energy facilities and the identification of effective mitigation measures.

  5. Avian influenza: an osteopathic component to treatment

    PubMed Central

    Hruby, Raymond J; Hoffman, Keasha N

    2007-01-01

    Avian influenza is an infection caused by the H5N1 virus. The infection is highly contagious among birds, and only a few known cases of human avian influenza have been documented. However, healthcare experts around the world are concerned that mutation or genetic exchange with more commonly transmitted human influenza viruses could result in a pandemic of avian influenza. Their concern remains in spite of the fact that the first United States vaccine against the H5N1 virus was recently approved. Under these circumstances the fear is that a pandemic of avian influenza could result in the kind of mortality that was seen with the Spanish influenza pandemic of 1918–1919, where the number of deaths was estimated to be as high as 40 million people. Retrospective data gathered by the American Osteopathic Association shortly after the 1918–1919 influenza pandemic have suggested that osteopathic physicians (DOs), using their distinctive osteopathic manipulative treatment (OMT) methods, observed significantly lower morbidity and mortality among their patients as compared to those treated by allopathic physicians (MDs) with standard medical care available at the time. In light of the limited prevention and treatment options available, it seems logical that a preparedness plan for the treatment of avian influenza should include these OMT procedures, provided by DOs and other healthcare workers capable of being trained to perform these therapeutic interventions. The purpose of this paper is to discuss the characteristics of avian influenza, describe the success of DOs during the 1918–1919 Spanish influenza pandemic, describe the evidence base for the inclusion of OMT as part of the preparedness plan for the treatment of avian influenza, and describe some of the specific OMT procedures that could be utilized as part of the treatment protocol for avian influenza patients. PMID:17620133

  6. A review of avian probiotics.

    PubMed

    Smith, Jeanne Marie

    2014-06-01

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

  7. Dual origin of avian lymphatics.

    PubMed

    Wilting, Jörg; Aref, Yama; Huang, Ruijin; Tomarev, Stanislav I; Schweigerer, Lothar; Christ, Bodo; Valasek, Petr; Papoutsi, Maria

    2006-04-01

    The earliest signs of the lymphatic vascular system are the lymph sacs, which develop adjacent to specific embryonic veins. It has been suggested that sprouts from the lymph sacs form the complete lymphatic vascular system. We have studied the origin of the jugular lymph sacs (JLS), the dermal lymphatics and the lymph hearts of avian embryos. In day 6.5 embryos, the JLS is an endothelial-lined sinusoidal structure. The lymphatic endothelial cells (LECs) stain (in the quail) positive for QH1 antibody and soybean agglutinin. As early as day 4, the anlagen of the JLS can be recognized by their Prox1 expression. Prox1 is found in the jugular section of the cardinal veins, and in scattered cells located in the dermatomes along the cranio-caudal axis and in the splanchnopleura. In the quail, such cells are positive for Prox1 and QH1. In the jugular region, the veins co-express the angiopoietin receptor Tie2. Quail-chick-chimera studies show that the peripheral parts of the JLS form by integration of cells from the paraxial mesoderm. Intra-venous application of DiI-conjugated acetylated low-density lipoprotein into day 4 embryos suggests a venous origin of the deep parts of the JLS. Superficial lymphatics are directly derived from the dermatomes, as shown by dermatome grafting. The lymph hearts in the lumbo-sacral region develop from a plexus of Prox1-positive lymphatic capillaries. Both LECs and muscle cells of the lymph hearts are of somitic origin. In sum, avian lymphatics are of dual origin. The deep parts of the lymph sacs are derived from adjacent veins, the superficial parts of the JLS and the dermal lymphatics from local lymphangioblasts. PMID:16457798

  8. Evolutionary origins of the avian brain.

    PubMed

    Balanoff, Amy M; Bever, Gabe S; Rowe, Timothy B; Norell, Mark A

    2013-09-01

    Features that were once considered exclusive to modern birds, such as feathers and a furcula, are now known to have first appeared in non-avian dinosaurs. However, relatively little is known of the early evolutionary history of the hyperinflated brain that distinguishes birds from other living reptiles and provides the important neurological capablities required by flight. Here we use high-resolution computed tomography to estimate and compare cranial volumes of extant birds, the early avialan Archaeopteryx lithographica, and a number of non-avian maniraptoran dinosaurs that are phylogenetically close to the origins of both Avialae and avian flight. Previous work established that avian cerebral expansion began early in theropod history and that the cranial cavity of Archaeopteryx was volumetrically intermediate between these early forms and modern birds. Our new data indicate that the relative size of the cranial cavity of Archaeopteryx is reflective of a more generalized maniraptoran volumetric signature and in several instances is actually smaller than that of other non-avian dinosaurs. Thus, bird-like encephalization indices evolved multiple times, supporting the conclusion that if Archaeopteryx had the neurological capabilities required of flight, so did at least some other non-avian maniraptorans. This is congruent with recent findings that avialans were not unique among maniraptorans in their ability to fly in some form. PMID:23903660

  9. Ecology and conservation biology of avian malaria.

    PubMed

    Lapointe, Dennis A; Atkinson, Carter T; Samuel, Michael D

    2012-02-01

    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. PMID:22320256

  10. Ecology and conservation biology of avian malaria

    USGS Publications Warehouse

    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.

  11. Avian influenza viruses and avian paramyxoviruses in wintering and breeding waterfowl populations in North Carolina, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although wild ducks are recognized reservoirs for avian influenza (AIV) and avian paramyxoviruses (APMV), information related to the prevalence of these viruses in breeding and migratory duck populations on North American wintering grounds is limited. Wintering (n=2,889) and resident breeding (n=524...

  12. Production of transgenic chickens using an avian retroviral vector

    SciTech Connect

    Kopchick, J.; Mills, E.; Rosenblum C.; Taylor, J.; Kelder, B.; Smith, J.; Chen, H.

    1987-05-01

    The authors efforts to insert genes into the chicken germ line are dependent upon the ability of exogenous avian retroviruses to infect chicken germ cells. They have used a transformation defective Schmidt Ruppin A strain of Rous Sarcoma Virus (RSV-SRA) in their initial experiments. The general protocol involved generating RSV-SRA viremic female chickens (Go), which shed exogenous virus via the oviduct. As the fertilized egg passes through the oviduct, embryonic cells are exposed to the virus. If the germ cell precursors are infected by the virus, offspring (G1) should be generated which are capable of passing the viral DNA to the next generation (G2). Fifteen viremic G1 males were selected for breeding and progeny testing. Since male chickens do not congenitally pass retroviruses through semen, production of viremic G2 offspring indicates germ line DNA transmission. This is confirmed by DNA analysis of the experimental chickens. Using a specific probe for exogenous retrovirus, they have detected the presence of RSV-SRA DNA in viremic chickens. Southern DNA analysis revealed junction fragments for RSV-SRA DNA in viremic G2 chickens, but not in non-viremic siblings. Furthermore, DNA isolated from various tissues of a viremic G2 chicken showed an identical DNA junction fragment pattern, indicating all tissues were derived from the same embryonic cell which contained integrated provirus. To date they have generated 50 transgenic chickens.

  13. High-Efficiency Ligation and Recombination of DNA Fragments by Vertebrate Cells

    NASA Astrophysics Data System (ADS)

    Miller, Cynthia K.; Temin, Howard M.

    1983-05-01

    DNA-mediated gene transfer (transfection) is used to introduce specific genes into vertebrate cells. Events soon after transfection were quantitatively analyzed by determining the infectivity of the DNA from an avian retrovirus and of mixtures of subgenomic fragments of this DNA. The limiting step of transfection with two DNA molecules is the uptake by a single cell of both DNA's in a biologically active state. Transfected cells mediate ligation and recombination of physically unlinked DNA's at nearly 100 percent efficiency.

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

    USGS Publications Warehouse

    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

  15. Heavy fragment radioactivities

    SciTech Connect

    Price, P.B.

    1987-12-10

    This recently discovered mode of radioactive decay, like alpha decay and spontaneous fission, is believed to involve tunneling through the deformation-energy barrier between a very heavy nucleus and two separated fragments the sum of whose masses is less than the mass of the parent nucleus. In all known cases the heavier of the two fragments is close to doubly magic /sup 208/Pb, and the lighter fragment has even Z. Four isotopes of Ra are known to emit /sup 14/C nuclei; several isotopes of U as well as /sup 230/Th and /sup 231/Pa emit Ne nuclei; and /sup 234/U exhibits four hadronic decay modes: alpha decay, spontaneous fission, Ne decay and Mg decay.

  16. Fragment screening: an introduction.

    PubMed

    Leach, Andrew R; Hann, Michael M; Burrows, Jeremy N; Griffen, Ed J

    2006-09-01

    There are clearly many different philosophies associated with adapting fragment screening into mainstream Drug Discovery Lead Generation strategies. Scientists at Astex, for instance, focus entirely on strategies involving use of X-ray crystallography and NMR. However, AstraZeneca uses a number of different fragment screening strategies. One approach is to screen a 2000 compound fragment set (with close to "lead-like" complexity) at 100 microM in parallel with every HTS such that the data are obtained on the entire screening collection at 10 microM plus the extra samples at 100 microM; this provides valuable compound potency data in a concentration range that is usually unexplored. The fragments are then screen-specific "privileged structures" that can be searched for in the rest of the HTS output and other databases as well as having synthesis follow-up. A typical workflow for a fragment screen within AstraZeneca is shown below (Figure 24) and highlights the desirability (particularly when screening >100 microM) for NMR and X-ray information to validate weak hits and give information on how to optimise them. In this chapter, we have provided an introduction to the theoretical and practical issues associated with the use of fragment methods and lead-likeness. Fragment-based approaches are still in an early stage of development and are just one of many interrelated techniques that are now used to identify novel lead compounds for drug development. Fragment based screening has some advantages, but like every other drug hunting strategy will not be universally applicable. There are in particular some practical challenges associated with fragment screening that relate to the generally lower level of potency that such compounds initially possess. Considerable synthetic effort has to be applied for post-fragment screening to build the sort of potency that would be expected to be found from a traditional HTS. However, if there are no low-hanging fruit in a screening

  17. Composition of cavity-nesting bird communities in montane aspen woodland fragments: The roles of landscape context and forest structure

    USGS Publications Warehouse

    Lawler, J.J.; Edwards, T.C., Jr.

    2002-01-01

    We compared cavity-nesting bird communities in aspen (Populus tremuloides) woodland fragments classified on the basis of vegetation structure (tree density) and landscape context (surrounding vegetation). We found very few cavity nesters in fragments predominantly surrounded by forests. Fragments adjacent to meadows contained more species and a greater abundance of cavity nesters. Species richness and abundance were higher in sparsely than in densely treed meadow fragments. Because secondary cavity nesters are often limited by cavity availability, we augmented natural cavities with nest boxes. Although only five boxes contained bird nests, these were all in sparse aspen fragments predominantly surrounded by meadows. However, we found 25 northern flying squirrel (Glaucomys sabrinus) nests in boxes, none of which were in sparse meadow fragments. In addition to high-lighting the importance of landscape context in avian and mammalian habitat relationships, our results suggest that predator or competitor interactions may help structure this cavity-nester community. ?? The Cooper Ornithological Society 2002.

  18. Activation of an Mg2+-dependent DNA endonuclease of avian myeloblastosis virus alpha beta DNA polymerase by in vitro proteolytic cleavage.

    PubMed Central

    Grandgenett, D P; Golomb, M; Vora, A C

    1980-01-01

    Partial chymotryptic digestion of purified avian myeloblastosis virus alpha beta DNA polymerase resulted in the activation of a Mg2+-dependent DNA endonuclease activity. Incubation of the polymerase-protease mixture in the presence of super-coiled DNA and Mg2+ permitted detection of the cleaved polymerase fragment possessing DNA nicking activity. Protease digestion conditions were established permitting selective cleavage of beta to alpha, which contained DNA polymerase and RNase H activity and to a family of polypeptides ranging in size from 30,000 to 34,000 daltons. These latter beta-unique fragments were purified by polyuridylate-Sepharose 4B chromatography and were shown to contain both DNA binding and DNA endonuclease activities. We have demonstrated that this group of polymerase fragments derived by chymotryptic digestion of alpha beta DNA polymerase is similar to the in vivo-isolated avian myeloblastosis virus p32pol in size, sequence, and DNA endonuclease activity. Images PMID:6154149

  19. Avian Influenza A (H7N9) Virus

    MedlinePlus

    ... this page: About CDC.gov . Avian Influenza H5 Viruses in the United States Updates and Publications Information ... Humans Examples of Human Infections with Avian Influenza Viruses Outbreaks Health Care and Laboratorian Guidance HPAI A ...

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

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Button Past Newsletters Prevention and Treatment of Avian Influenza A Viruses in People Language: English Español ...

  1. Avian cholera in Nebraska's Rainwater Basin

    USGS Publications Warehouse

    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. IMPACT fragmentation model developments

    NASA Astrophysics Data System (ADS)

    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

  3. Target fragmentation in radiobiology

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Cucinotta, Francis A.; Shinn, Judy L.; Townsend, Lawrence W.

    1993-01-01

    Nuclear reactions in biological systems produce low-energy fragments of the target nuclei seen as local high events of linear energy transfer (LET). A nuclear-reaction formalism is used to evaluate the nuclear-induced fields within biosystems and their effects within several biological models. On the basis of direct ionization interaction, one anticipates high-energy protons to have a quality factor and relative biological effectiveness (RBE) of unity. Target fragmentation contributions raise the effective quality factor of 10 GeV protons to 3.3 in reasonable agreement with RBE values for induced micronuclei in bean sprouts. Application of the Katz model indicates that the relative increase in RBE with decreasing exposure observed in cell survival experiments with 160 MeV protons is related solely to target fragmentation events. Target fragment contributions to lens opacity given an RBE of 1.4 for 2 GeV protons in agreement with the work of Lett and Cox. Predictions are made for the effective RBE for Harderian gland tumors induced by high-energy protons. An exposure model for lifetime cancer risk is derived from NCRP 98 risk tables, and protraction effects are examined for proton and helium ion exposures. The implications of dose rate enhancement effects on space radiation protection are considered.

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

    SciTech Connect

    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.

  5. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Pasteurella Multocida Vaccine, Avian... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or...

  6. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Pasteurella Multocida Vaccine, Avian... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or...

  7. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Pasteurella Multocida Vaccine, Avian... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or...

  8. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Pasteurella Multocida Vaccine, Avian... REQUIREMENTS Live Bacterial Vaccines § 113.70 Pasteurella Multocida Vaccine, Avian Isolate. Pasteurella Multocida Vaccine, Avian Isolate, shall be prepared as a desiccated live culture of an avirulent or...

  9. Avian Metapneumovirus Subgroup C Infection in Chickens, China

    PubMed Central

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

    2013-01-01

    Avian metapneumovirus causes acute respiratory tract infection and reductions in egg production in various avian species. We isolated and characterized an increasingly prevalent avian metapneumovirus subgroup C strain from meat-type commercial chickens with severe respiratory signs in China. Culling of infected flocks could lead to economic consequences. PMID:23763901

  10. The prevention and control of avian influenza: The avian influenza coordinated agriculture project1

    PubMed Central

    Cardona, C.; Slemons, R.; Perez, D.

    2015-01-01

    The Avian Influenza Coordinated Agriculture Project (AICAP) entitled “Prevention and Control of Avian Influenza in the US” strives to be a significant point of reference for the poultry industry and the general public in matters related to the biology, risks associated with, and the methods used to prevent and control avian influenza. To this end, AICAP has been remarkably successful in generating research data, publications through an extensive network of university- and agency-based researchers, and extending findings to stakeholders. An overview of the highlights of AICAP research is presented. PMID:19276431

  11. Generation of Avian Induced Pluripotent Stem Cells.

    PubMed

    Lu, Yangqing; West, Franklin D; Jordan, Brian J; Beckstead, Robert B; Jordan, Erin T; Stice, Steven L

    2015-01-01

    Avian species are among the most diverse vertebrates on our planet and significantly contribute to the balance of the ecology. They are also important food source and serve as a central animal model to decipher developmental biology and disease principles. Derivation of induced pluripotent stem cells (iPSCs) from avian species would enable conservation of genetic diversity as well as offer a valuable cell source that facilitates the use of avian models in many areas of basic and applied research. In this chapter, we describe methods used to successfully reprogram quail fibroblasts into iPSCs by using human transcription factors and the techniques critical to the characterization of their pluripotency. PMID:26621592

  12. The ubiquity of avian ultraviolet plumage reflectance.

    PubMed Central

    Eaton, Muir D; Lanyon, Scott M

    2003-01-01

    Although several bird species have been shown to reflect ultraviolet (UV) light from their plumages, the incidence of UV reflectance, and therefore the potential for UV or UV-enhanced signals, across the avian tree of life is not known. In this study, we collected reflectance data from the plumages of 312 bird species representing 142 families. Our results demonstrate that all avian families possess plumages that reflect significant amounts of UV light. The ubiquity of UV reflectance indicates that all studies of avian behaviour, ecology and evolution involving plumage coloration would benefit from consideration of plumage reflectance in the UV portion of the electromagnetic spectrum. Additionally, we demonstrate the existence of cryptic UV plumage patches and cryptic dimorphism among birds. PMID:12965000

  13. Avian influenza surveillance of wild birds

    USGS Publications Warehouse

    Slota, Paul

    2007-01-01

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

  14. Shielding and fragmentation studies.

    PubMed

    Zeitlin, C; Guetersloh, S; Heilbronn, L; Miller, J

    2005-01-01

    Radiation dosimetry for manned spaced missions depends on the ability to adequately describe the process of high-energy ion transport through many materials. Since the types of possible nuclear interactions are many and complex, transport models are used which depend upon a reliable source of experimental data. To expand the heavy ion database used in the models we have been measuring charge-changing cross sections and fragment production cross sections from heavy-ion interactions in various elementa targets. These include materials flown on space missions such as carbon and aluminium, as well as those important in radiation dosimetry such as hydrogen, nitrogen and water. Measuring heavy-ion fragmentation through these targets also gives us the ability to determine the effectiveness of new materials proposed for shielding such as graphite composites and polyethylene hybrids. Measurement without a target present gives an indication of the level of contamination of the primary beam, which is also important in radiobiology experiments. PMID:16604611

  15. Fragmentation of cancer cells

    NASA Astrophysics Data System (ADS)

    Vanapalli, Siva; Kamyabi, Nabiollah

    Tumor cells have to travel through blood capillaries to be able to metastasize and colonize in distant organs. Among the numerous cells that are shed by the primary tumor, very few survive in circulation. In vivo studies have shown that tumor cells can undergo breakup at microcapillary junctions affecting their survival. It is currently unclear what hydrodynamic and biomechanical factors contribute to fragmentation and moreover how different are the breakup dynamics of highly and weakly metastatic cells. In this study, we use microfluidics to investigate flow-induced breakup of prostate and breast cancer cells. We observe several different modes of breakup of cancer cells, which have striking similarities with breakup of viscous drops. We quantify the breakup time and find that highly metastatic cancer cells take longer to breakup than lowly metastatic cells suggesting that tumor cells may dynamically modify their deformability to avoid fragmentation. We also identify the role that cytoskeleton and membrane plays in the breakup process. Our study highlights the important role that tumor cell fragmentation plays in cancer metastasis. Cancer Prevention and Research Institute of Texas.

  16. Electroeluting DNA fragments.

    PubMed

    Zarzosa-Alvarez, Ana L; Sandoval-Cabrera, Antonio; Torres-Huerta, Ana L; Bermudez-Cruz, Rosa M

    2010-01-01

    Purified DNA fragments are used for different purposes in Molecular Biology and they can be prepared by several procedures. Most of them require a previous electrophoresis of the DNA fragments in order to separate the band of interest. Then, this band is excised out from an agarose or acrylamide gel and purified by using either: binding and elution from glass or silica particles, DEAE-cellulose membranes, "crush and soak method", electroelution or very often expensive commercial purification kits. Thus, selecting a method will depend mostly of what is available in the laboratory. The electroelution procedure allows one to purify very clean DNA to be used in a large number of applications (sequencing, radiolabeling, enzymatic restriction, enzymatic modification, cloning etc). This procedure consists in placing DNA band-containing agarose or acrylamide slices into sample wells of the electroeluter, then applying current will make the DNA fragment to leave the agarose and thus be trapped in a cushion salt to be recovered later by ethanol precipitation. PMID:20834225

  17. Fracture, failure, and fragmentation

    SciTech Connect

    Dienes, J.K.

    1984-01-01

    Though continuum descriptions of material behavior are useful for many kinds of problems, particularly those involving plastic flow, a more general approach is required when the failure is likely to involve growth and coalescence of a large number of fractures, as in fragmentation. Failures of this kind appear frequently in rapid dynamic processes such as those resulting from impacts and explosions, particularly in the formation of spall fragments. In the first part of this paper an approach to formulating constitutive relations that accounts for the opening, shear and growth of an ensemble of cracks is discussed. The approach also accounts for plastic flow accompanying fragmentation. The resulting constitutive relations have been incorporated into a Lagrangean computer program. In the second part of this paper a theoretical approach to coalescence is described. The simplest formulation makes use of a linear Liouville equation, with crack growth limited by the mean free path of cracks, assumed constant. This approach allows for an anisotropic distribution of cracks. An alternative approach is also described in which the decrease of the mean free path with increasing crack size is accounted for, but the crack distribution is assumed isotropic. A reduction of the governing Liouville equation to an ordinary differential equation of third order is possible, and the result can be used to determine how mean-free-path decreases with increasing crack size.

  18. Thermal emissivity of avian eggshells.

    PubMed

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

    2016-04-01

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

  19. Host Tissue and Glycan Binding Specificities of Avian Viral Attachment Proteins Using Novel Avian Tissue Microarrays

    PubMed Central

    Ambepitiya Wickramasinghe, Iresha N.; de Vries, Robert P.; Eggert, Amber M.; Wandee, Nantaporn; de Haan, Cornelis A. M.; Gröne, Andrea; Verheije, Monique H.

    2015-01-01

    The initial interaction between viral attachment proteins and the host cell is a critical determinant for the susceptibility of a host for a particular virus. To increase our understanding of avian pathogens and the susceptibility of poultry species, we developed novel avian tissue microarrays (TMAs). Tissue binding profiles of avian viral attachment proteins were studied by performing histochemistry on multi-species TMA, comprising of selected tissues from ten avian species, and single-species TMAs, grouping organ systems of each species together. The attachment pattern of the hemagglutinin protein was in line with the reported tropism of influenza virus H5N1, confirming the validity of TMAs in profiling the initial virus-host interaction. The previously believed chicken-specific coronavirus (CoV) M41 spike (S1) protein displayed a broad attachment pattern to respiratory tissues of various avian species, albeit with lower affinity than hemagglutinin, suggesting that other avian species might be susceptible for chicken CoV. When comparing tissue-specific binding patterns of various avian coronaviral S1 proteins on the single-species TMAs, chicken and partridge CoV S1 had predominant affinity for the trachea, while pigeon CoV S1 showed marked preference for lung of their respective hosts. Binding of all coronaviral S1 proteins was dependent on sialic acids; however, while chicken CoV S1 preferred sialic acids type I lactosamine (Gal(1-3)GlcNAc) over type II (Gal(1-4)GlcNAc), the fine glycan specificities of pigeon and partridge CoVs were different, as chicken CoV S1-specific sialylglycopolymers could not block their binding to tissues. Taken together, TMAs provide a novel platform in the field of infectious diseases to allow identification of binding specificities of viral attachment proteins and are helpful to gain insight into the susceptibility of host and organ for avian pathogens. PMID:26035584

  20. Molecular detection of the avian malaria parasite Plasmodium gallinaceum in Thailand.

    PubMed

    Pattaradilokrat, Sittiporn; Tiyamanee, Wisawa; Simpalipan, Phumin; Kaewthamasorn, Morakot; Saiwichai, Tawee; Li, Jian; Harnyuttanakorn, Pongchai

    2015-05-30

    Avian malaria is one of the most common veterinary problems in Southeast Asia. The standard molecular method for detection of the avian malaria parasite involves the phenol-chloroform extraction of parasite genomic (g)DNA followed by the amplification of parasite gDNA using polymerase chain reaction (PCR). However, the phenol-chloroform extraction method is time-consuming and requires large amounts of samples and toxic organic solvents, thereby limiting its applications for parasite detection in the field. This study aimed to compare the performance of chelex-100 resin and phenol/chloroform extraction methods for the extraction of Plasmodium gallinaceum gDNA from whole avian blood that had been dried on filter papers (a common field sampling method). The specificity and sensitivity of PCR assays for P. gallinaceum cytochrome B (cytb) and cytochrome oxidase subunit I (coxI) gene fragments (544 and 588bp, respectively) were determined, and found to be more sensitive with gDNA extracted by the chelex-100 resin method than with the phenol/chloroform method. These PCR assays were also performed to detect P. gallinaceum in 29 blood samples dried on filter papers from domestic chickens in a malaria endemic area, where the reliable identification of seven field isolates of P. gallinaceum was obtained with an accuracy of 100%. The analysis of cytb and coxI gene nucleotide sequences revealed the existence of at least two genetically distinct populations of P. gallinaceum in Thailand, both of which differed from the reference strain 8A of P. gallinaceum. In conclusion, the chelex-100 resin extraction method is a simple and sensitive method for isolating gDNA from whole avian blood dried on filter paper. Genomic DNA extracted by the chelex method could subsequently be applied for the PCR-based detection of P. gallinaceum and DNA sequencing. Our PCR assays provide a reliable diagnostic tool for molecular epidemiological studies of P. gallinaceum infections in domestic chickens

  1. Fragment-based lead design

    NASA Astrophysics Data System (ADS)

    Filz, O. A.; Poroikov, Vladimir V.

    2012-02-01

    State-of-the-art approaches to the fragment-based design of organic compounds with desired properties are considered. The review covers methods, which are used in different steps of the design, such as computational methods for fragment library design, experimental and computational methods for fragment discovery and methods for the generation of structures of organic compounds. Examples are given of drug candidates, which were constructed using the fragment-based approach. The bibliography includes 156 references.

  2. Transcriptional analysis of the innate immune response using the avian innate immunity microarray

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The avian innate immunity microarray (AIIM) is a genomics tool designed to study the transcriptional activity of the avian immune response (Cytogenet. Genome Res. 117:139-145, 2007). It is an avian cDNA microarray representing 4,959 avian genes spotted in triplicate. The AIIM contains 25 avian int...

  3. Crystallization of the C-terminal globular domain of avian reovirus fibre

    SciTech Connect

    Raaij, Mark J. van; Hermo Parrado, X. Lois; Guardado Calvo, Pablo; Fox, Gavin C.; Llamas-Saiz, Antonio L.; Costas, Celina; Martínez-Costas, José; Benavente, Javier

    2005-07-01

    Partial proteolysis of the avian reovirus cell-attachment protein σC yields a major homotrimeric C-terminal fragment that presumably contains the receptor-binding domain. This fragment has been crystallized in the presence and absence of zinc sulfate and cadmium sulfate. One of the crystal forms diffracts synchrotron X-rays to 2.2–2.3 Å. Avian reovirus fibre, a homotrimer of the σC protein, is responsible for primary host-cell attachment. Using the protease trypsin, a C-terminal σC fragment containing amino acids 156–326 has been generated which was subsequently purified and crystallized. Two different crystal forms were obtained, one grown in the absence of divalent cations and belonging to space group P6{sub 3}22 (unit-cell parameters a = 75.6, c = 243.1 Å) and one grown in the presence of either zinc or cadmium sulfate and belonging to space group P321 (unit-cell parameters a = 74.7, c = 74.5 Å and a = 73.1, c = 69.9 Å for the Zn{sup II}- and Cd{sup II}-grown crystals, respectively). The first crystal form diffracted synchrotron radiation to 3.0 Å resolution and the second form to 2.2–2.3 Å. Its closest related structure, the C-terminal fragment of mammalian reovirus fibre, has only 18% sequence identity and molecular-replacement attempts were unsuccessful. Therefore, a search is under way for suitable heavy-atom derivatives and attempts are being made to grow protein crystals containing selenomethionine instead of methionine.

  4. Avian Schistosomes and Outbreaks of Cercarial Dermatitis

    PubMed Central

    Mikeš, Libor; Lichtenbergová, Lucie; Skála, Vladimír; Soldánová, Miroslava; Brant, Sara Vanessa

    2015-01-01

    SUMMARY Cercarial dermatitis (swimmer's itch) is a condition caused by infective larvae (cercariae) of a species-rich group of mammalian and avian schistosomes. Over the last decade, it has been reported in areas that previously had few or no cases of dermatitis and is thus considered an emerging disease. It is obvious that avian schistosomes are responsible for the majority of reported dermatitis outbreaks around the world, and thus they are the primary focus of this review. Although they infect humans, they do not mature and usually die in the skin. Experimental infections of avian schistosomes in mice show that in previously exposed hosts, there is a strong skin immune reaction that kills the schistosome. However, penetration of larvae into naive mice can result in temporary migration from the skin. This is of particular interest because the worms are able to migrate to different organs, for example, the lungs in the case of visceral schistosomes and the central nervous system in the case of nasal schistosomes. The risk of such migration and accompanying disorders needs to be clarified for humans and animals of interest (e.g., dogs). Herein we compiled the most comprehensive review of the diversity, immunology, and epidemiology of avian schistosomes causing cercarial dermatitis. PMID:25567226

  5. Pathobiology of avian influenza in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic ducks are an important source of food and income in many parts of the world. The susceptibility of domestic ducks to avian influenza (AI) viruses varies depending on many factors, including the species and the age of the ducks, the virus strain, and management practices. Although wild wat...

  6. Avian paramyxoviruses in shorebirds and gulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian paramyxoviruses (APMV) consist of nine serotypes including APMV-1, or Newcastle disease virus (NDV). Although free-flying ducks and geese have been extensively monitored for APMV, limited information is available for species in the order Charadriiformes. From 2000 to 2005 we tested cloacal swa...

  7. Viral vectors for avian influenza vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. Oxygen radical production by avian leukocytes.

    PubMed

    Conlon, P; Smith, D; Gowlett, T

    1991-04-01

    Oxygen radical production by heterophils of red-tailed hawks and chickens, and by neutrophils of calves, was evaluated in a chemiluminescence microassay. Leukocytes were isolated by centrifugation of blood in capillary tubes and then challenged with opsonized zymosan in the presence of luminol. Avian heterophils produced significantly fewer oxygen radicals than did bovine neutrophils. PMID:1884301

  9. Rapid molecular diagnostic tools for avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An accurate and early diagnosis of a foreign animal disease is crucial for rapid control and eradication of an outbreak in a country previously free of the disease. Historically many animal diseases have been controlled based solely on clinical signs of disease. However with avian influenza virus ...

  10. Avian influenza vaccines and vaccination for poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines against avian influenza (AI) have had more limited use in poultry than vaccines against other poultry diseases such as Newcastle disease (ND) and infectious bronchitis, and have been used more commonly in the developing world. Over the past 40 years, AI vaccines have been primarily based o...

  11. An in depth view of avian sleep.

    PubMed

    Beckers, Gabriël J L; Rattenborg, Niels C

    2015-03-01

    Brain rhythms occurring during sleep are implicated in processing information acquired during wakefulness, but this phenomenon has almost exclusively been studied in mammals. In this review we discuss the potential value of utilizing birds to elucidate the functions and underlying mechanisms of such brain rhythms. Birds are of particular interest from a comparative perspective because even though neurons in the avian brain homologous to mammalian neocortical neurons are arranged in a nuclear, rather than a laminar manner, the avian brain generates mammalian-like sleep-states and associated brain rhythms. Nonetheless, until recently, this nuclear organization also posed technical challenges, as the standard surface EEG recording methods used to study the neocortex provide only a superficial view of the sleeping avian brain. The recent development of high-density multielectrode recording methods now provides access to sleep-related brain activity occurring deep in the avian brain. Finally, we discuss how intracerebral electrical imaging based on this technique can be used to elucidate the systems-level processing of hippocampal-dependent and imprinting memories in birds. PMID:25107492

  12. Avian influenza vaccines and therapies for poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines have been used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein. A variety of vaccines have been developed and tested under experimenta...

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

    PubMed

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

    2012-07-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. Patterns of avian nest predators and a brood parasite among restored riparian habitats in agricultural watersheds.

    PubMed

    Maul, Jonathan D; Smiley, Peter C; Cooper, Charles M

    2005-09-01

    In fragmented edge-dominated landscapes, nest predation and brood parasitism may reduce avian reproductive success and, ultimately, populations of some passerine species. In the fragmented agroecosystem of northwest Mississippi, placement of drop-pipe structures has been used as a restoration technique for abating gully erosion along stream banks. These actions have formed small herbaceous and woody habitat extensions into former agricultural lands. We quantified species relative abundances, species richness, and evenness of avian nest predators and a brood parasite within four categories of constructed habitat resulting from drop-pipe installation. Differences in the abundance of two nest predators, cotton mouse (Peromyscus gossypinus) and blue jay (Cyanocitta cristata), were observed among constructed habitats. However, relative abundances of other predators such as common grackle (Quiscalus quiscula), American crow (Corvus brachyrhynchos), and hispid cotton rat (Sigmodon hispidus), and the obligate brood parasite brown-headed cowbird (Molothrus ater) did not differ among four habitat categories. Although species richness, abundance, and evenness of potential nest predators were generally similar among the constructed habitats, predator species composition varied, suggesting that these habitats supported different predator communities. This difference is important because as each predator species is added to or deleted from the community, variation may occur in the framework of prey search methods, predator strategies, and potentially overall predation pressure. We suggest that land managers using drop-pipes as part of stream restoration projects allow for the development of the constructed habitat with the largest area and greatest vegetative structure. PMID:16160783

  16. Virtual fragment preparation for computational fragment-based drug design.

    PubMed

    Ludington, Jennifer L

    2015-01-01

    Fragment-based drug design (FBDD) has become an important component of the drug discovery process. The use of fragments can accelerate both the search for a hit molecule and the development of that hit into a lead molecule for clinical testing. In addition to experimental methodologies for FBDD such as NMR and X-ray Crystallography screens, computational techniques are playing an increasingly important role. The success of the computational simulations is due in large part to how the database of virtual fragments is prepared. In order to prepare the fragments appropriately it is necessary to understand how FBDD differs from other approaches and the issues inherent in building up molecules from smaller fragment pieces. The ultimate goal of these calculations is to link two or more simulated fragments into a molecule that has an experimental binding affinity consistent with the additive predicted binding affinities of the virtual fragments. Computationally predicting binding affinities is a complex process, with many opportunities for introducing error. Therefore, care should be taken with the fragment preparation procedure to avoid introducing additional inaccuracies.This chapter is focused on the preparation process used to create a virtual fragment database. Several key issues of fragment preparation which affect the accuracy of binding affinity predictions are discussed. The first issue is the selection of the two-dimensional atomic structure of the virtual fragment. Although the particular usage of the fragment can affect this choice (i.e., whether the fragment will be used for calibration, binding site characterization, hit identification, or lead optimization), general factors such as synthetic accessibility, size, and flexibility are major considerations in selecting the 2D structure. Other aspects of preparing the virtual fragments for simulation are the generation of three-dimensional conformations and the assignment of the associated atomic point charges

  17. Tube Fragmentation of Multiple Materials

    SciTech Connect

    Thornhill, T. F.; Chhabildas, L. C.; Vogler, T. J.

    2006-07-28

    In the current study we are developing an experimental fracture material property test method specific to dynamic fragmentation. This test method allows the study of fracture fragmentation in a reproducible laboratory environment under well-controlled loading conditions. Motion and fragmentation of the specimen are diagnosed using framing camera, VISAR and soft recovery methods. Fragmentation properties of several steels, nitinol, tungsten alloy, copper, aluminum, and titanium have been obtained to date. The values for fragmentation toughness, and failure threshold will be reported, as well as effects in these values as the material strain-rate is varied through changes in wall thickness and impact conditions.

  18. Tube fragmentation of multiple materials.

    SciTech Connect

    Thornhill, Tom Finley, III; Vogler, Tracy John; Chhabildas, Lalit Chandra

    2003-07-01

    In the current study we are developing an experimental fracture material property test method specific to dynamic fragmentation. This test method allows the study of fracture fragmentation in a reproducible laboratory environment under well-controlled loading conditions. Motion and fragmentation of the specimen are diagnosed using framing camera, VISAR and soft recovery methods. Fragmentation properties of several steels, nitinol, tungsten alloy, copper, aluminum, and titanium have been obtained to date. The values for fragmentation toughness, and failure threshold will be reported, as well as effects in these values as the material strain-rate is varied through changes in wall thickness and impact conditions.

  19. New Scalings in Nuclear Fragmentation

    SciTech Connect

    Bonnet, E.; Bougault, R.; Galichet, E.; Gagnon-Moisan, F.; Guinet, D.; Lautesse, P.; Marini, P.; Parlog, M.

    2010-10-01

    Fragment partitions of fragmenting hot nuclei produced in central and semiperipheral collisions have been compared in the excitation energy region 4-10 MeV per nucleon where radial collective expansion takes place. It is shown that, for a given total excitation energy per nucleon, the amount of radial collective energy fixes the mean fragment multiplicity. It is also shown that, at a given total excitation energy per nucleon, the different properties of fragment partitions are completely determined by the reduced fragment multiplicity (i.e., normalized to the source size). Freeze-out volumes seem to play a role in the scalings observed.

  20. A clinical survey of common avian infectious diseases in China.

    PubMed

    Zhuang, Qing-Ye; Wang, Su-Chun; Li, Jin-Ping; Liu, Dong; Liu, Shuo; Jiang, Wen-Ming; Chen, Ji-Ming

    2014-06-01

    Multiple common avian infectious diseases (CAIDs), namely, avian infectious diseases excluding highly pathogenic avian influenza and Newcastle disease, such as avian salmonellosis and coccidiosis, cause huge economic loss in poultry production and are of great significance in public health. However, they are usually not covered in the systems for reporting of animal diseases. Consequently, the distribution of CAIDs is not clear in many countries. Here, we report a clinical survey of CAIDs in China based on clinical diagnosis of eight veterinary clinics in 2011 and 2012. This survey provided the distribution data of viral, bacterial, and parasitic CAIDs in different types of avian flocks, seasons, and regions, data that are of great value in the research, prevention, and control of poultry diseases. This survey suggested that avian colibacillosis, infectious serositis in ducks caused by Riemerella anatipestifer, avian salmonellosis, fowl cholera, avian mycoplasmosis, avian aspergillosis, coccidiosis, low pathogenic avian influenza, infectious bronchitis, infectious bursal disease, and infectious laryngotracheitis are likely to be prevalent in the poultry in China. PMID:25055636

  1. Remote Sensing and Avian Biodiversity Patterns in the United States

    NASA Astrophysics Data System (ADS)

    Culbert, Patrick Davis

    Avian biodiversity is threatened, and in order to prioritize limited conservation resources and conduct effective conservation planning, a better understanding of avian species richness patterns is needed. In general, habitat structure, climatic stability, and sensed data to characterize these three drivers at a national scale, determine the influence and relative importance of these drivers of avian biodiversity, and produce nationwide, predictive maps of avian species richness for all birds, forest birds, grassland birds, shrubland birds, Neotropical migrants, short-distance migrants, and permanent residents. The quantification of habitat structure from remotely sensed data was a primary objective, including the evaluation of remotely sensed image texture and both horizontal and vertical vegetation structure, such as landscape composition and forest canopy height. These measures explained up to 70 percent of variability in avian species richness across the United States, and vertical and horizontal structure measures were complementary. I then developed models of avian species richness as a function of all three drivers of biodiversity. When modeling avian species richness at the scale of a North American Breeding Bird Survey route, all three factors had some explanatory power, but measures of habitat structure dominated, followed by productivity, then climatic stability. Models for specific avian guilds explained between 21 and 67 percent of the variability in avian species richness. Lastly, in order to generate a product useful to planners and resource managers, I produced a nationwide, 30-m spatial resolution map of predicted avian species richness for each of the seven avian guilds. My dissertation makes several technical, theoretical, and applied contributions to biodiversity conservation. The main technical contribution is the use of remotely sensed image texture over a nationwide extent. Theoretical contributions include the evaluation of the relative

  2. Scaling behavior of fragment shapes.

    PubMed

    Kun, F; Wittel, F K; Herrmann, H J; Kröplin, B H; Måløy, K J

    2006-01-20

    We present an experimental and theoretical study of the shape of fragments generated by explosive and impact loading of closed shells. Based on high speed imaging, we have determined the fragmentation mechanism of shells. Experiments have shown that the fragments vary from completely isotropic to highly anisotropic elongated shapes, depending on the microscopic cracking mechanism of the shell. Anisotropic fragments proved to have a self-affine character described by a scaling exponent. The distribution of fragment shapes exhibits a power-law decay. The robustness of the scaling laws is illustrated by a stochastic hierarchical model of fragmentation. Our results provide a possible improvement of the representation of fragment shapes in models of space debris. PMID:16486594

  3. Fragment oriented molecular shapes.

    PubMed

    Hain, Ethan; Camacho, Carlos J; Koes, David Ryan

    2016-05-01

    Molecular shape is an important concept in drug design and virtual screening. Shape similarity typically uses either alignment methods, which dynamically optimize molecular poses with respect to the query molecular shape, or feature vector methods, which are computationally less demanding but less accurate. The computational cost of alignment can be reduced by pre-aligning shapes, as is done with the Volumetric-Aligned Molecular Shapes (VAMS) method. Here, we introduce and evaluate fragment oriented molecular shapes (FOMS), where shapes are aligned based on molecular fragments. FOMS enables the use of shape constraints, a novel method for precisely specifying molecular shape queries that provides the ability to perform partial shape matching and supports search algorithms that function on an interactive time scale. When evaluated using the challenging Maximum Unbiased Validation dataset, shape constraints were able to extract significantly enriched subsets of compounds for the majority of targets, and FOMS matched or exceeded the performance of both VAMS and an optimizing alignment method of shape similarity search. PMID:27085751

  4. Avian demography in mosaic landscapes: modeling paradigm and preliminary results

    SciTech Connect

    Urban, D.L.; Shugart, H.H. Jr.

    1984-01-01

    We pursued a mechanistic explanation for the local extinction of some avian species from small and/or isolated patches in a habitat mosaic. A model was developed to simulate demographic processes of natality, dispersal, and mortality as these might occur in a mosaic of discrete habitat patches. These processes were adjusted to reflect life-history attributes that seem to confer sensitivity to habitat fragmentation. We used the model to explore the effects of restricted vagility and reduced natality resulting from biotic interactions for a hypothetical bird species. Restricted vagility resulted in local extinctions in small, isolated patches, but this effect was buffered by an available pool of surplus nonbreeders. Lower natality reduced this suplus so as to increase the frequency of local extinction, and allowed restricted vagility to play a more important role in affecting species distribution. Moderate levels of restricted vagility and reduced natality were synergistic in effect. In general, small patches in isolation tended to lose their populations permanently, large patches rarely suffered extinctions, but small and intermediate patches adjacent to other patches suffered extinctions and were recolonized repeatedly. The basic modeling approach can be expanded to include greater mechanistic detail, but implementation has been limited by a lack of appropriate data. Our preliminary results suggest which data are necessary to pursue a mechanistic, patch-scale understanding of species demography at the landscape scale. 17 references, 5 figures, 3 tables.

  5. Chapter 4 embedded metal fragments.

    PubMed

    Kalinich, John F; Vane, Elizabeth A; Centeno, Jose A; Gaitens, Joanna M; Squibb, Katherine S; McDiarmid, Melissa A; Kasper, Christine E

    2014-01-01

    The continued evolution of military munitions and armor on the battlefield, as well as the insurgent use of improvised explosive devices, has led to embedded fragment wounds containing metal and metal mixtures whose long-term toxicologic and carcinogenic properties are not as yet known. Advances in medical care have greatly increased the survival from these types of injuries. Standard surgical guidelines suggest leaving embedded fragments in place, thus individuals may carry these retained metal fragments for the rest of their lives. Nursing professionals will be at the forefront in caring for these wounded individuals, both immediately after the trauma and during the healing and rehabilitation process. Therefore, an understanding of the potential health effects of embedded metal fragment wounds is essential. This review will explore the history of embedded fragment wounds, current research in the field, and Department of Defense and Department of Veterans Affairs guidelines for the identification and long-term monitoring of individuals with embedded fragments. PMID:25222538

  6. Avian influenza virus and free-ranging wild birds

    USGS Publications Warehouse

    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.

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

    SciTech Connect

    Harmata, A.; Podruzny, K.; Zelenak, J.

    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.

  8. IDENTIFICATION OF AVIAN-SPECIFIC FECAL METAGENOMIC SEQUENCES USING GENOME FRAGMENT ENRICHMENTS

    EPA Science Inventory

    Sequence analysis of microbial genomes has provided biologists the opportunity to compare genetic differences between closely related microorganisms. While random sequencing has also been used to study natural microbial communities, metagenomic comparisons via sequencing analysis...

  9. Avian Influenza Virus and DIVA Strategies.

    PubMed

    Hasan, Noor Haliza; Ignjatovic, Jagoda; Peaston, Anne; Hemmatzadeh, Farhid

    2016-05-01

    Vaccination is becoming a more acceptable option in the effort to eradicate avian influenza viruses (AIV) from commercial poultry, especially in countries where AIV is endemic. The main concern surrounding this option has been the inability of the conventional serological tests to differentiate antibodies produced due to vaccination from antibodies produced in response to virus infection. In attempts to address this issue, at least six strategies have been formulated, aiming to differentiate infected from vaccinated animals (DIVA), namely (i) sentinel birds, (ii) subunit vaccine, (iii) heterologous neuraminidase (NA), (iv) nonstructural 1 (NS1) protein, (v) matrix 2 ectodomain (M2e) protein, and (vi) haemagglutinin subunit 2 (HA2) glycoprotein. This short review briefly discusses the strengths and limitations of these DIVA strategies, together with the feasibility and practicality of the options as a part of the surveillance program directed toward the eventual eradication of AIV from poultry in countries where highly pathogenic avian influenza is endemic. PMID:26900835

  10. Avian circadian organization: a chorus of clocks.

    PubMed

    Cassone, Vincent M

    2014-01-01

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

  11. Isolation and characterization of a gene involved in hemagglutination by an avian pathogenic Escherichia coli strain.

    PubMed Central

    Provence, D L; Curtiss, R

    1994-01-01

    In this article, we report the isolation and characterization of a gene that may be important in the adherence of avian pathogenic Escherichia coli to the avian respiratory tract. The E. coli strain HB101, which is unable to agglutinate chicken erythrocytes, was transduced with cosmid libraries from the avian pathogenic E. coli strain chi 7122. Enrichment of transductants that could agglutinate chicken erythrocytes yielded 19 colonies. These isolates contained cosmids that encompassed four nonoverlapping regions of the E. coli chromosome. Only one group of cosmids, represented by pYA3104, would cause E. coli CC118 to agglutinate chicken erythrocytes. A 10-kb fragment of this cosmid was subcloned in pACYC184. Transposon mutagenesis of this fragment with Tn5seq1 indicated that a contiguous 4.4-kb region of cloned DNA was required for hemagglutination. In vitro transcription/translation assays indicated that this 4.4-kb region of DNA encoded one protein of approximately 140 kDa. The nucleotide sequence of this region was determined and found to encode one open reading frame of 4,134 nucleotides that would encode a protein of 1,377 amino acids with a deduced molecular weight of 148,226. This gene confers on E. coli K-12 a temperature-sensitive hemagglutination phenotype that is best expressed when cells are grown at 26 degrees C, and we have designated this gene tsh and the deduced gene product Tsh. Insertional mutagenesis of the chromosomal tsh gene in chi 7122 had no effect on hemagglutination titers. The deduced protein was found to contain significant homology to the Haemophilus influenzae and Neisseria gonorrhoeae immunoglobulin A1 proteases. These data indicate that (i) a single gene isolated from the avian pathogenic E. coli strain chi 7122 will confer on E. coli K-12 a hemagglutination-positive phenotype, (ii) chi 7122 contains at least two distinct mechanisms to allow hemagglutination to occur, and (iii) the hemagglutinin Tsh has homology with a class of

  12. Expornitic of avian pox in a zoo.

    PubMed

    Ensley, P K; Anderson, M P; Costello, M L; Powell, H C; Cooper, R

    1978-11-01

    During a 6-week period at the San Diego Zoo, avian pox occurred in 9 pheasants representing 5 species. Lesions were limited to facial skin and consisted of epithelial cell hyperplasia, secondary inflammatory changes, and intracytoplasmic eosinophilic inclusion bodies which, by electron microscopy, were shown to contain pox virus. The disease was self-limiting in 7 pheasants, but 2 pheasants died. Free-ranging Indian red junglefowl were implicated as the source of the infection. PMID:216657

  13. The avian egg and the retina

    PubMed Central

    MALCOLM, J. E.

    1973-01-01

    A mathematical model for study of blood flow has been derived from the avian egg, utilizing the theories of crystallography and photosynthesis. The model is employed to explain the form of the eye and the function of the cells of the human retina, with special reference to colour vision and the pathology of migraine. ImagesFig. 1Fig. 4Fig. 5Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:4736600

  14. Common Avian Infection Plagued the Tyrant Dinosaurs

    PubMed Central

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

    2009-01-01

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

  15. Conservation planning and monitoring avian habitat

    USGS Publications Warehouse

    Twedt, D.J.; Loesch, C.R.

    2000-01-01

    Migratory bird conservation plans should not only develop population goals, they also should establish attainable objectives for optimizing avian habitats. Meeting population goals is of paramount importance, but progress toward established habitat objectives can generally be monitored more easily than can progress toward population goals. Additionally, local or regional habitat objectives can be attained regardless of perturbations to avian populations that occur outside the geographic area covered by conservation plans. Assessments of current avian habitats, obtained from remotely sensed data, and the historical distribution of habitats should be used in establishing habitat objectives. Habitat planning and monitoring are best conducted using a geographic information system. Habitat objectives are assigned to three categories: maintaining existing habitat, restoring habitat, and creating new or alternative habitat. Progress toward meeting habitat objectives can be monitored through geographic information systems by incorporating georeferenced information on public lands, private lands under conservation easements, corporate lands under prescribed management, habitat restoration areas, and private lands under alternative management to enhance wildlife values. We recommend that the area and distribution of habitats within the area covered by conservation plans be reassessed from remotely sensed imagery at intervals appropriate to detect predicted habitat changes.

  16. Cognitive ornithology: the evolution of avian intelligence

    PubMed Central

    Emery, Nathan J

    2005-01-01

    Comparative psychologists interested in the evolution of intelligence have focused their attention on social primates, whereas birds tend to be used as models of associative learning. However, corvids and parrots, which have forebrains relatively the same size as apes, live in complex social groups and have a long developmental period before becoming independent, have demonstrated ape-like intelligence. Although, ornithologists have documented thousands of hours observing birds in their natural habitat, they have focused their attention on avian behaviour and ecology, rather than intelligence. This review discusses recent studies of avian cognition contrasting two different approaches; the anthropocentric approach and the adaptive specialization approach. It is argued that the most productive method is to combine the two approaches. This is discussed with respects to recent investigations of two supposedly unique aspects of human cognition; episodic memory and theory of mind. In reviewing the evidence for avian intelligence, corvids and parrots appear to be cognitively superior to other birds and in many cases even apes. This suggests that complex cognition has evolved in species with very different brains through a process of convergent evolution rather than shared ancestry, although the notion that birds and mammals may share common neural connectivity patterns is discussed. PMID:16553307

  17. ["Avian pests" and their very long history].

    PubMed

    Blancou, Jean

    2006-01-01

    Avian influenza is a contagious disease of birds widely spread in wild fowl (namely ducks) and most feared in domestic birds, which may be infected with the highly pathogenic strains of the virus (HPAI). Some mammals, including human beings, may also be affected and die. Specific tools for the diagnosis of HPAI were not available before 1955, but since then more than 25 outbreaks were reported throughout the world, with an unusual incidence in Asia and Europe after 2003. However, before 1955 and since the Antiquity, numerous important outbreaks have been reported in Europe in domestic or wild birds, with high morbidity and mortality rates. Such outbreaks involved either poultry (including domestic geese or ducks) or wild birds (water fowl or land fowl). As far as the latter were concerned, some authors of the Middle-Ages attributed the large-scale deaths of birds to pitched battles between different avian species. Many details are given on the places and dates of these outbreaks, as well as on their epidemiological features. The author recalls the need for strengthening the surveillance and control of HPAI to minimize any risk of pandemic following a genetic re-assortment of avian and human influenza viruses. PMID:16869099

  18. [Contribution to the history of avian plagues].

    PubMed

    Blancou, Jean

    2006-01-01

    Avian influenza is a contagious disease of birds widely spread in wild fowl (namely ducks) and most feared in domestic birds, which may be infected with the highly pathogenic strains of the virus (HPAI). Some mammals, including human beings, may also be affected and die. Specific tools for the diagnosis of HPAI were not available before 1955, but since then more than 25 outbreaks were reported throughout the world, with an unusual incidence in Asia and Europe after 2003. However, before 1955 and since the Antiquity, numerous important outbreaks have been reported in Europe in domestic or wild birds, with high morbidity and mortality rates. Such outbreaks involved either poultry (including domestic geese or ducks) or wild birds (water fowl or land fowl). As far as the latter were concerned, some authors of the Middle-Ages attributed the large-scale deaths of birds to pitched battles between different avian species. Many details are given on the places and dates of these outbreaks, as well as on their epidemiological features. The author recalls the need for strengthening the surveillance and control of HPAI to minimize any risk of pandemic following a genetic re-assortment of avian and human influenza viruses. PMID:17575848

  19. Fragmentation pathways of polymer ions.

    PubMed

    Wesdemiotis, Chrys; Solak, Nilüfer; Polce, Michael J; Dabney, David E; Chaicharoen, Kittisak; Katzenmeyer, Bryan C

    2011-01-01

    Tandem mass spectrometry (MS/MS) is increasingly applied to synthetic polymers to characterize chain-end or in-chain substituents, distinguish isobaric and isomeric species, and determine macromolecular connectivities and architectures. For confident structural assignments, the fragmentation mechanisms of polymer ions must be understood, as they provide guidelines on how to deduce the desired information from the fragments observed in MS/MS spectra. This article reviews the fragmentation pathways of synthetic polymer ions that have been energized to decompose via collisionally activated dissociation (CAD), the most widely used activation method in polymer analysis. The compounds discussed encompass polystyrenes, poly(2-vinyl pyridine), polyacrylates, poly(vinyl acetate), aliphatic polyester copolymers, polyethers, and poly(dimethylsiloxane). For a number of these polymers, several substitution patterns and architectures are considered, and questions regarding the ionization agent and internal energy of the dissociating precursor ions are also addressed. Competing and consecutive dissociations are evaluated in terms of the structural insight they provide about the macromolecular structure. The fragmentation pathways of the diverse array of polymer ions examined fall into three categories, viz. (1) charge-directed fragmentations, (2) charge-remote rearrangements, and (3) charge-remote fragmentations via radical intermediates. Charge-remote processes predominate. Depending on the ionizing agent and the functional groups in the polymer, the incipient fragments arising by pathways (1)-(3) may form ion-molecule complexes that survive long enough to permit inter-fragment hydrogen atom, proton, or hydride transfers. PMID:20623599

  20. Fragment-based drug design.

    PubMed

    Feyfant, Eric; Cross, Jason B; Paris, Kevin; Tsao, Désirée H H

    2011-01-01

    Fragment-based drug design (FBDD), which is comprised of both fragment screening and the use of fragment hits to design leads, began more than 15 years ago and has been steadily gaining in popularity and utility. Its origin lies on the fact that the coverage of chemical space and the binding efficiency of hits are directly related to the size of the compounds screened. Nevertheless, FBDD still faces challenges, among them developing fragment screening libraries that ensure optimal coverage of chemical space, physical properties and chemical tractability. Fragment screening also requires sensitive assays, often biophysical in nature, to detect weak binders. In this chapter we will introduce the technologies used to address these challenges and outline the experimental advantages that make FBDD one of the most popular new hit-to-lead process. PMID:20981527

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

    PubMed

    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. PMID:24548306

  2. Pathogenesis and pathobiology of avian influenza virus infection in birds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) viruses vary in their ability to produce infection, disease and death in different bird species. Based on the pathobiological features in chickens, AI viruses are categorized as, low (LP) and high pathogenicity (HP). Typically, LPAI (low pathogenicity avian influenza) viruses ...

  3. THE MOLECULAR BIOLOGY OF AVIAN INFLUENZA VIRUS IN SHORT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is an important pathogen of poultry as it can cause severe economic losses through disease, including respiratory signs and mortality, and effects on trade. Avian influenza virus is classified as type A influenza, which is a member of the orthomyxoviridae family. Charact...

  4. 9 CFR 113.325 - Avian Encephalomyelitis Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.325 Avian Encephalomyelitis Vaccine. Avian Encephalomyelitis Vaccine shall be prepared from virus-bearing tissues or fluids from embryonated chicken eggs. Only Master...

  5. 9 CFR 113.325 - Avian Encephalomyelitis Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.325 Avian Encephalomyelitis Vaccine. Avian Encephalomyelitis Vaccine shall be prepared from virus-bearing tissues or fluids from embryonated chicken eggs. Only Master...

  6. 9 CFR 113.325 - Avian Encephalomyelitis Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.325 Avian Encephalomyelitis Vaccine. Avian Encephalomyelitis Vaccine shall be prepared from virus-bearing tissues or fluids from embryonated chicken eggs. Only Master...

  7. Rapid diagnostics for avian influenza -- Advances in testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of tools are available for the diagnosis of avian influenza virus. They can be generally divided into the serologic diagnostic tests and direct virus detection tests. The serologic tests are important primarily for active surveillance to assure our poultry flocks are free of avian influe...

  8. Sequencing of avian influenza virus genomes following random amplification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) is a significant disease of birds and a threat to humans. Recently, as a result of the emergence of Asian H5N1 viruses capable of zoonotic spread, wild and domestic bird surveillance for Avian Influenza viruses (AIV) has increased worldwide, requiring the development of fast a...

  9. Avian influenza in Indonesia: Observations of disease detection in poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic avian influenza, subtype H5N1, also known as highly pathogenic notifiable avian influenza (HPNAI), has spread throughout Indonesia since 2003. As of June 2007 there have been a total of 100 documented human cases in Indonesia, 80 of which have been fatal. Although efforts have be...

  10. Experimental vaccinations for avian influenza virus including DIVA approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 (HP) AIV has become endemic in several regions of the world. Vaccination f...

  13. A simple vitrification method for cryobanking avian testicular tissue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cryopreservation of testicular tissue is a promising method of preserving male reproductive potential for avian species. This study was conducted to assess whether a vitrification method can be used to preserve avian testicular tissue, using the Japanese quail (Coturnix japonica) as a model. A sim...

  14. Avian cholera and organochlorine residues in an American oystercatcher

    USGS Publications Warehouse

    Blus, L.J.; Locke, L.N.; Cromartie, E.

    1978-01-01

    Pasteurella multocida, the causative bacterium of avian cholera, was isolated from cultures of the liver and heart blood of a female, adult American oystercatcher (Haematopus palliatus) found dead on the Cape Romain National Wildlife Refuge, South Carolina, in May 1973. This is apparently the first record of avian cholera in the oystercatcher. Low levels of DDE were identified in tissues of the oystercatcher.

  15. Measurement of avian cytokines with real time RT-PCR following infection with avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both functional and molecular techniques have been employed to measure the production of cytokines following influenza infection. Historically, the use of functional or antibody based techniques were employed in mammalian immunology. In avian immunology, only a few commercial antibodies are availa...

  16. Susceptibility of avian species to north american H13 low pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

  17. Comparative susceptibility of avian species to low pathogenic avian influenza viruses of the H13 subtype

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

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

    USGS Publications Warehouse

    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. Immediate early responses of avian tracheal epithelial cells to infection with highly pathogenic avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic (HP) avian influenza viruses (AIV) present an on going threat to the U.S. poultry industry. In order to develop new AIV control strategies it is necessary to understand the underlying mechanism of viral infection. Because the early events of AIV infection can occur on tracheal ep...

  20. Immediate early responses of avian tracheal epithelial cells to infection with highly pathogenic avian invluenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic (HP) avian influenza viruses (AIV) present an ongoing threat to the world poultry industry. In order to develop new AIV control strategies it is necessary to understand the underlying mechanism of viral infection at mucosal respiratory sites. Chicken and duck tracheal epithelial ...

  1. Origin of the European avian-like swine influenza viruses.

    PubMed

    Krumbholz, Andi; Lange, Jeannette; Sauerbrei, Andreas; Groth, Marco; Platzer, Matthias; Kanrai, Pumaree; Pleschka, Stephan; Scholtissek, Christoph; Büttner, Mathias; Dürrwald, Ralf; Zell, Roland

    2014-11-01

    The avian-like swine influenza viruses emerged in 1979 in Belgium and Germany. Thereafter, they spread through many European swine-producing countries, replaced the circulating classical swine H1N1 influenza viruses, and became endemic. Serological and subsequent molecular data indicated an avian source, but details remained obscure due to a lack of relevant avian influenza virus sequence data. Here, the origin of the European avian-like swine influenza viruses was analysed using a collection of 16 European swine H1N1 influenza viruses sampled in 1979-1981 in Germany, the Netherlands, Belgium, Italy and France, as well as several contemporaneous avian influenza viruses of various serotypes. The phylogenetic trees suggested a triple reassortant with a unique genotype constellation. Time-resolved maximum clade credibility trees indicated times to the most recent common ancestors of 34-46 years (before 2008) depending on the RNA segment and the method of tree inference. PMID:25073465

  2. Proceedings: Avian Interactions with Utility Structures. International Workshop

    SciTech Connect

    Not Available

    1993-12-01

    The first international workshop on Avian Interactions with Utility Structures featured an exchange of information on the impact of utility structures on avian populations. EPRI cosponsored the workshop with the Avian Power Line Interaction Committee (APLIC), formed in 1988 and designed to share data and experience regarding avian interactions with utility structures. The workshop -- held September 13--16, 1992 in Miami-welcomed engineers, scientists, academic researchers, and representatives from conservation and special interest groups. Attendees from 10 countries presented 28 papers that provide a basis for understanding and establishing new research directions to reduce bird mortality due to collisions and electrocutions. Papers highlighted advances in technology and analysis tools, the geographic extent of the problem, and regulatory needs of utilities and other interested parties involved in preventing and mitigating avian/power line interaction problems.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Susceptibility of selected wild avian species to experimental infection with H5N1 high pathogenicity avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2002, H5N1 highly pathogenic avian influenza (HPAI) viruses have caused mortality in wide diversity of wild avian species but, to date, the role that different species play in the transmission and maintenance of H5N1 HPAI viruses is poorly understood. To begin to address these uncertainties a...

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

    PubMed

    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. PMID:25655260

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

    PubMed

    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. PMID:24001810

  7. Fragmentation Function in Thermofield Dynamics

    NASA Astrophysics Data System (ADS)

    Ladrem, M.; Chekerker, M.; Khanna, F. C.; Santana, A. E.

    2013-04-01

    The fragmentation function at high energy experiments is introduced by using thermofield dynamics (TFD), a real-time finite-temperature quantum field formalism. Due to the structure of TFD, the results at T = 0 and T ≠ 0 are split in a direct way. As an application, we consider the temperature effect on the fragmentation function of a hadron leading to quark-antiquark pairs. Using a definition of Wilson-loop in real-time, we find that the fragmentation function decreases in magnitude with an increase in the temperature.

  8. Velocity fluctuations of fission fragments

    NASA Astrophysics Data System (ADS)

    Llanes-Estrada, Felipe J.; Carmona, Belén Martínez; Martínez, Jose L. Muñoz

    2016-02-01

    We propose event by event velocity fluctuations of nuclear fission fragments as an additional interesting observable that gives access to the nuclear temperature in an independent way from spectral measurements and relates the diffusion and friction coefficients for the relative fragment coordinate in Kramers-like models (in which some aspects of fission can be understood as the diffusion of a collective variable through a potential barrier). We point out that neutron emission by the heavy fragments can be treated in effective theory if corrections to the velocity distribution are needed.

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

    PubMed

    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. PMID:25119733

  10. Newcastle disease and other avian paramyxoviruses.

    PubMed

    Alexander, D J

    2000-08-01

    Newcastle disease (ND), caused by avian paramyxovirus serotype 1 (APMV-1) viruses, is included in List A of the Office International des Epizooties. Historically, ND has been a devastating disease of poultry, and in many countries the disease remains one of the major problems affecting existing or developing poultry industries. Even in countries where ND may be considered to be controlled, an economic burden is still associated with vaccination and/or maintaining strict biosecurity measures. The variable nature of Newcastle disease virus strains in terms of virulence for poultry and the different susceptibilities of the different species of birds mean that for control and trade purposes, ND requires careful definition. Confirmatory diagnosis of ND requires the isolation and characterisation of the virus involved. Assessments of virulence conventionally require in vivo testing. However, in vitro genetic characterisation of viruses is being used increasingly now that the molecular basis of pathogenicity is more fully understood. Control of ND is by prevention of introduction and spread, good biosecurity practices and/or vaccination. Newcastle disease viruses may infect humans, usually causing transient conjunctivitis, but human-to-human spread has never been reported. Eight other serotypes of avian paramyxoviruses are recognised, namely: APMV-2 to APMV-9. Most of these serotypes appear to be present in natural reservoirs of specific feral avian species, although other host species are usually susceptible. Only APMV-2 and APMV-3 viruses have made a significant disease and economic impact on poultry production. Both types of viruses cause respiratory disease and egg production losses which may be severe when exacerbated by other infections or environmental stresses. No reports exist of natural infections of chickens with APMV-3 viruses. PMID:10935273

  11. The Avian Transcriptome Response to Malaria Infection

    PubMed Central

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

    2015-01-01

    Malaria parasites are highly virulent pathogens which infect a wide range of vertebrates. Despite their importance, the way different hosts control and suppress malaria infections remains poorly understood. With recent developments in next-generation sequencing techniques, however, it is now possible to quantify the response of the entire transcriptome to infections. We experimentally infected Eurasian siskins (Carduelis spinus) with avian malaria parasites (Plasmodium ashfordi), and used high-throughput RNA-sequencing to measure the avian transcriptome in blood collected before infection (day 0), during peak parasitemia (day 21 postinfection), and when parasitemia was decreasing (day 31). We found considerable differences in the transcriptomes of infected and uninfected individuals, with a large number of genes differentially expressed during both peak and decreasing parasitemia stages. These genes were overrepresented among functions involved in the immune system, stress response, cell death regulation, metabolism, and telomerase activity. Comparative analyses of the differentially expressed genes in our study to those found in other hosts of malaria (human and mouse) revealed a set of genes that are potentially involved in highly conserved evolutionary responses to malaria infection. By using RNA-sequencing we gained a more complete view of the host response, and were able to pinpoint not only well-documented host genes but also unannotated genes with clear significance during infection, such as microRNAs. This study shows how the avian blood transcriptome shifts in response to malaria infection, and we believe that it will facilitate further research into the diversity of molecular mechanisms that hosts utilize to fight malaria infections. PMID:25636457

  12. Avian genetics: A field and ecological approach

    SciTech Connect

    Cooke, F.; Buckley, P.A.

    1987-01-01

    The authors wanted to present the ecological/population approach they used in their own research, and a compendium of carefully referred chapters written by invited experts was essential. The book follows the historical evolution of work in avian genetics, proceeding from a discussion of Mendelian (i.e. classical) genes through quantitative genetics, chromosomal genetics, biochemical genetics, to extensive treatment of population genetics, and concluding with some examples of long-term studies. In this book concentration has been more on intra- than on inter-specific variation; in that sense the approach has been more genetic than evolutionary or taxonomic.

  13. Avian artificial insemination and semen preservation

    USGS Publications Warehouse

    Gee, G.F.

    1983-01-01

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

  14. USGS highly pathogenic avian influenza research strategy

    USGS Publications Warehouse

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

    2015-01-01

    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. Fragmentation of drying paint layers

    NASA Astrophysics Data System (ADS)

    Bakos, Katinka; Dombi, András; Járai-Szabó, Ferenc; Néda, Zoltán

    2013-11-01

    Fragmentation of thin layers of drying granular materials on a frictional surface are studied both by experiments and computer simulations. Besides a qualitative description of the fragmentation phenomenon, the dependence of the average fragment size as a function of the layer thickness is thoroughly investigated. Experiments are done using a special nail polish, which forms characteristic crack structures during drying. In order to control the layer thickness, we diluted the nail polish in acetone and evaporated in a controlled manner different volumes of this solution on glass surfaces. During the evaporation process we managed to get an instable paint layer, which formed cracks as it dried out. In order to understand the obtained structures a previously developed spring-block model was implemented in a three-dimensional version. The experimental and simulation results proved to be in excellent qualitative and quantitative agreement. An earlier suggested scaling relation between the average fragment size and the layer thickness is reconfirmed.

  16. (Natural fragmentation of exploding cylinders)

    SciTech Connect

    Grady, D.E.; Hightower, M.M.

    1990-01-01

    The natural fragmentation of a 4140 steel cylinder fully loaded with RX-35-AN insensitive high explosive is investigated through experiment and analysis. Methods of Taylor and Gurney are used to determine the fracture strain and kinematic state of the expanding cylinder. Energy methods based on mechanisms of both tension fracture and adiabatic shear fracture are used to calculate the circumferential fragmentation intensity. 9 refs., 5 figs.

  17. Recovery of avian metapneumovirus subgroup C from cDNA: cross-recognition of avian and human metapneumovirus support proteins.

    PubMed

    Govindarajan, Dhanasekaran; Buchholz, Ursula J; Samal, Siba K

    2006-06-01

    Avian metapneumovirus (AMPV) causes an acute respiratory disease in turkeys and is associated with "swollen head syndrome" in chickens, contributing to significant economic losses for the U.S. poultry industry. With a long-term goal of developing a better vaccine for controlling AMPV in the United States, we established a reverse genetics system to produce infectious AMPV of subgroup C entirely from cDNA. A cDNA clone encoding the entire 14,150-nucleotide genome of AMPV subgroup C strain Colorado (AMPV/CO) was generated by assembling five cDNA fragments between the T7 RNA polymerase promoter and the autocatalytic hepatitis delta virus ribozyme of a transcription plasmid, pBR 322. Transfection of this plasmid, along with the expression plasmids encoding the N, P, M2-1, and L proteins of AMPV/CO, into cells stably expressing T7 RNA polymerase resulted in the recovery of infectious AMPV/CO. Characterization of the recombinant AMPV/CO showed that its growth properties in tissue culture were similar to those of the parental virus. The potential of AMPV/CO to serve as a viral vector was also assessed by generating another recombinant virus, rAMPV/CO-GFP, that expressed the enhanced green fluorescent protein (GFP) as a foreign protein. Interestingly, GFP-expressing AMPV and GFP-expressing human metapneumovirus (HMPV) could be recovered using the support plasmids of either virus, denoting that the genome promoters are conserved between the two metapneumoviruses and can be cross-recognized by the polymerase complex proteins of either virus. These results indicate a close functional relationship between AMPV/CO and HMPV. PMID:16731918

  18. Fragmentation of hot classical drops

    SciTech Connect

    Vicentini, A.; Jacucci, G.; Pandharipande, V.R.

    1985-05-01

    Time evolution of hot drops of matter containing approx.230 or approx.130 particles is studied by classical molecular dynamics. Initially, the drops have uniform density and a sharp surface. The chosen initial conditions include three values of density and a range of temperatures wide enough to study the phenomena of evaporation, fragmentation, and total vaporization in a unified fashion. The average density and temperature of central matter is measured periodically to obtain trajectories of the evolution in the rho,T plane. These trajectories indicate that the matter expands almost adiabatically until it reaches the region of adiabatic instabilities. Density inhomogeneities develop in this region, but the matter fragments only if the expansion continues to average densities of less than one-fourth the liquid density, otherwise it recondenses into a single blob. The recondensed matter and fragments have very crooked surfaces. If the temperature is high enough, the expanding matter does not enter the region of adiabatic instabilities and totally vaporizes. For initial densities of the order of equilibrium density, matter does not fragment or develop large inhomogeneities in the region enclosed by the isothermal and adiabatic spinodals. Thus it appears unlikely that fragmentation of small drops (nuclei) can be used to study the isothermal critical region of gas-liquid phase transition. A detailed tabulation of the energies and number of monomers, dimers, light, and heavy fragments emitted in each event is presented.

  19. Population genetic structure of male black grouse (Tetrao tetrix L.) in fragmented vs. continuous landscapes.

    PubMed

    Caizergues, Alain; Rätti, Osmo; Helle, Pekka; Rotelli, Luca; Ellison, Laurence; Rasplus, Jean-Yves

    2003-09-01

    We investigated the association of habitat fragmentation with genetic structure of male black grouse Tetrao tetrix. Using 14 microsatellites, we compared the genetic differentiation of males among nine localities in continuous lowland habitats in Finland to the genetic differentiation among 14 localities in fragmented habitats in the Alps (France, Switzerland and Italy). In both areas, we found significant genetic differentiation. However, the average differentiation, measured as theta, was more than three times higher in the Alps than in Finland. The greater differentiation found in the Alps is probably due to the presence of mountain ridges rising above natural habitats of the species, which form barriers to gene flow, and to a higher influence of genetic drift resulting from lower effective sizes in highly fragmented habitats. The detection of isolation by distance in the Alps suggests that gene flow among populations does occur. The genetic variability measured as gene diversity HE and allelic richness A was lower in the Alps than in Finland. This could result from the higher fragmentation and/or from the fact that populations in the Alps are isolated from the main species range and have a lower effective size than in Finland. This study suggests that habitat fragmentation can affect genetic structure of avian species with relatively high dispersal propensities. PMID:12919469

  20. Pandemic Threat Posed by Avian Influenza A Viruses

    PubMed Central

    Horimoto, Taisuke; Kawaoka, Yoshihiro

    2001-01-01

    Influenza pandemics, defined as global outbreaks of the disease due to viruses with new antigenic subtypes, have exacted high death tolls from human populations. The last two pandemics were caused by hybrid viruses, or reassortants, that harbored a combination of avian and human viral genes. Avian influenza viruses are therefore key contributors to the emergence of human influenza pandemics. In 1997, an H5N1 influenza virus was directly transmitted from birds in live poultry markets in Hong Kong to humans. Eighteen people were infected in this outbreak, six of whom died. This avian virus exhibited high virulence in both avian and mammalian species, causing systemic infection in both chickens and mice. Subsequently, another avian virus with the H9N2 subtype was directly transmitted from birds to humans in Hong Kong. Interestingly, the genes encoding the internal proteins of the H9N2 virus are genetically highly related to those of the H5N1 virus, suggesting a unique property of these gene products. The identification of avian viruses in humans underscores the potential of these and similar strains to produce devastating influenza outbreaks in major population centers. Although highly pathogenic avian influenza viruses had been identified before the 1997 outbreak in Hong Kong, their devastating effects had been confined to poultry. With the Hong Kong outbreak, it became clear that the virulence potential of these viruses extended to humans. PMID:11148006

  1. Collapsing avian community on a Hawaiian island.

    PubMed

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

    2016-09-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua'i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species' ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua'i represents an early warning for the forest bird communities on the Maui and Hawai'i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing. PMID:27617287

  2. Studying avian encephalization with geometric morphometrics.

    PubMed

    Marugán-Lobón, Jesús; Watanabe, Akinobu; Kawabe, Soichiro

    2016-08-01

    Encephalization is a core concept in comparative neurobiology, aiming to quantify the neurological capacity of organisms. For measuring encephalization, many studies have employed relative brain sizes corrected for expected allometric scaling to body size. Here we highlight the utility of a multivariate geometric morphometric (GM) approach for visualizing and analyzing neuroanatomical shape variation associated with encephalization. GM readily allows the statistical evaluation of covariates, such as size, and many software tools exist for visualizing their effects on shape. Thus far, however, studies using GM have not attempted to translate the meaning of encephalization to shape data. As such, we tested the statistical relationship between size and encephalization quotients (EQs) to brain shape utilizing a broad interspecific sample of avian endocranial data. Although statistically significant, the analyses indicate that allometry accounts for <10% of total neuroanatomical shape variation. Notably, we find that EQs, despite being corrected for allometric scaling based on size, contain size-related neuroanatomical shape changes. In addition, much of what is traditionally considered encephalization comprises clade-specific trends in relative forebrain expansion, particularly driven by landbirds. EQs, therefore, fail to capture 90% of the total neuroanatomical variation after correcting for allometry and shared phylogenetic history. Moving forward, GM techniques provide crucial tools for investigating key drivers of this vast, largely unexplored aspect of avian brain morphology. PMID:27112986

  3. Avian Bornaviruses in North American Gulls.

    PubMed

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

    2015-07-01

    Avian bornaviruses, recently described members of the family Bornaviridae, have been isolated from captive parrots and passerines as well as wild waterfowl in which they may cause lethal neurologic disease. We report detection of avian bornavirus RNA in the brains of apparently healthy gulls. We tested 439 gull brain samples from 18 states, primarily in the northeastern US, using a reverse-transcriptase PCR assay with primers designed to detect a conserved region of the bornavirus M gene. Nine birds yielded a PCR product of appropriate size. Sequencing of PCR products indicated that the virus was closely related to aquatic bird bornavirus 1 (ABBV-1). Viral RNA was detected in Herring Gulls (Larus argentatus), Ring-billed Gulls (Larus delawarensis), and Laughing Gulls (Leucophaeus atricilla). Eight of the nine positive birds came from the New York/New Jersey area. One positive Herring Gull came from New Hampshire. Histopathologic examination of one well-preserved brain from a Herring Gull from Union County New Jersey, showed a lymphocytic encephalitis similar to that observed in bornavirus-infected parrots and geese. Bornavirus N protein was confirmed in two Herring Gull brains by immunohistochemistry. Thus ABBV-1 can infect gulls and cause encephalitic brain lesions similar to those observed in other birds. PMID:25973630

  4. Ecology of avian influenza virus in birds.

    PubMed

    Causey, Douglas; Edwards, Scott V

    2008-02-15

    Avian influenza A virus (an orthomyxovirus) is a zoonotic pathogen with a natural reservoir entirely in birds. The influenza virus genome is an 8-segment single-stranded RNA with high potential for in situ recombination. Two segments code for the hemagglutinin (H) and neuraminidase (N) antigens used for host-cell entry. At present, 16 H and 9 N subtypes are known, for a total of 144 possible different influenza subtypes, each with potentially different host susceptibility. With >10,000 species of birds found in nearly every terrestrial and aquatic habitat, there are few places on earth where birds cannot be found. The avian immune system differs from that of humans in several important features, including asynchronous B and T lymphocyte systems and a polymorphic multigene immune complex, but little is known about the immunogenetics of pathogenic response. Postbreeding dispersal and migration and a naturally high degree of environmental vagility mean that wild birds have the potential to be vectors that transmit highly pathogenic variants great distances from the original sources of infection. PMID:18269325

  5. Collapsing avian community on a Hawaiian island

    PubMed Central

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

    2016-01-01

    The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing. PMID:27617287

  6. Avian colibacillosis: still many black holes.

    PubMed

    Guabiraba, Rodrigo; Schouler, Catherine

    2015-08-01

    Avian pathogenic Escherichia coli (APEC) strains cause severe respiratory and systemic diseases, threatening food security and avian welfare worldwide. Intensification of poultry production and the quick expansion of free-range production systems will increase the incidence of colibacillosis through greater exposure of birds to pathogens and stress. Therapy is mainly based on antibiotherapy and current vaccines have poor efficacy. Serotyping remains the most frequently used diagnostic method, only allowing the identification of a limited number of APEC strains. Several studies have demonstrated that the most common virulence factors studied in APEC are all rarely present in the same isolate, showing that APEC strains constitute a heterogeneous group. Different isolates may harbor different associations of virulence factors, each one able to induce colibacillosis. Despite its economical relevance, pathogenesis of colibacillosis is poorly understood. Our knowledge on the host response to APEC is based on very descriptive studies, mostly restricted to bacteriological and histopathological analysis of infected organs such as lungs. Furthermore, only a small number of APEC isolates have been used in experimental studies. In the present review, we discuss current knowledge on APEC diversity and virulence, including host response to infection and the associated inflammatory response with a focus on pulmonary colibacillosis. PMID:26204893

  7. Fragmentation Pathways in the Uracil Radical Cation

    SciTech Connect

    Zhou, Congyi; Matsika, Spiridoula; Kotur, Marija; Weinacht, Thomas C.

    2012-08-24

    We investigate pathways for fragmentation in the uracil radical cation using ab initio electronic structure calculations. We focus on the main fragments produced in pump–probe dissociative ionization experiments. These are fragments with mass to charge ratios (m/z) of 69, 28, 41, and 42. Barriers to dissociation along the ground ionic surface are reported, which provide an estimate of the energetic requirements for the production of the main fragments. Finally, direct and sequential fragmentation mechanisms have been analyzed, and it is concluded that sequential fragmentation after production of fragment with m/z 69 is the dominant mechanism for the production of the smaller fragments.

  8. Avians as a Model System of Vascular Development

    PubMed Central

    Bressan, Michael; Mikawa, Takashi

    2015-01-01

    Summary For more then 2000 years philosophers and scientists have turned to the avian embryo with questions of how life begins (Aristotle; Needham, 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, have 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. PMID:25468608

  9. Fragmentation and ablation during entry

    SciTech Connect

    Canavan, G.H.

    1997-09-01

    This note discusses objects that both fragment and ablate during entry, using the results of previous reports to describe the velocity, pressure, and fragmentation of entering objects. It shows that the mechanisms used there to describe the breakup of non-ablating objects during deceleration remain valid for most ablating objects. It treats coupled fragmentation and ablation during entry, building on earlier models that separately discuss the entry of objects that are hard, whose high heat of ablation permits little erosion, and those who are strong whose strength prevents fragmentation, which are discussed in ``Radiation from Hard Objects,`` ``Deceleration and Radiation of Strong, Hard, Asteroids During Atmospheric Impact,`` and ``Meteor Signature Interpretation.`` This note provides a more detailed treatment of the further breakup and separation of fragments during descent. It replaces the constraint on mass per unit area used earlier to determine the altitude and magnitude of peak power radiation with a detailed analytic solution of deceleration. Model predictions are shown to be in agreement with the key features of numerical calculations of deceleration. The model equations are solved for the altitudes of maximum radiation, which agree with numerical integrations. The model is inverted analytically to infer object size and speed from measurements of peak power and altitude to provide a complete model for the approximate inversion of meteor data.

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

    PubMed Central

    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. PMID:24688871

  11. Shared epitopes of avian immunoglobulin light chains.

    PubMed

    Benčina, Mateja; Cizelj, Ivanka; Berčič, Rebeka Lucijana; Narat, Mojca; Benčina, Dušan; Dovč, Peter

    2014-04-15

    Like all jawed vertebrates, birds (Aves) also produce antibodies i.e. immunoglobulins (Igs) as a defence mechanism against pathogens. Their Igs are composed of two identical heavy (H) and light (L) chains which are of lambda isotype. The L chain consists of variable (VL), joining (JL) and constant (CL) region. Using enzyme immunoassays (EIA) and two monoclonal antibodies (mAbs) (3C10 and CH31) to chicken L chain, we analysed their cross-reactivity with sera from 33 avian species belonging to nine different orders. Among Galliformes tested, mAbs 3C10 and CH31 reacted with L chains of chicken, turkey, four genera of pheasants, tragopan and peafowl, but not with sera of grey partridge, quail and Japanese quail. Immunoglobulins of guinea-fowl reacted only with mAb 3C10. Both mAbs reacted also with the L chain of Eurasian griffon (order Falconiformes) and domestic sparrow (order Passeriformes). Sera from six other orders of Aves did not react with either of the two mAbs. EIA using mAbs 3C10 and CH31 enabled detection of antibodies to major avian pathogens in sera of chickens, turkeys, pheasants, peafowl, Eurasian griffon and guinea-fowl (only with mAb 3C10). The N-terminal amino acid sequence of pheasant L chain (19 residues) was identical to that of chicken. Sequences of genes encoding the L chain constant regions of pheasants, turkey and partridge were determined and deposited in the public database (GenBank accession numbers: FJ 649651, FJ 649652 and FJ 649653, respectively). Among them, amino acid sequence of pheasants is the most similar to that of chicken (97% similarity), whereas those of turkey and partridge have greater similarity to each other (89%) than to any other avian L chain sequence. The characteristic deletion of two amino acids which is present in the L chain constant region in Galliformes has been most likely introduced to their L chain after their divergence from Anseriformes. PMID:24603015

  12. Chemical ions affect survival of avian cholera organisms in pondwater

    USGS Publications Warehouse

    Price, J.I.; Yandell, B.S.; Porter, W.P.

    1992-01-01

    Avian cholera (Pasteurella multocida) is a major disease of wild waterfowl, but its epizootiology remains little understood. Consequently, we examined whether chemical ions affected survival of avian cholera organisms in water collected from the Nebraska Rainwater Basin where avian cholera is enzootic. We tested the response of P. multocida to ammonium (NH4), calcium (Ca), magnesium (Mg), nitrate (NO3), and ortho-phosphate (PO4) ions individually and in combination using a fractional factorial design divided into 4 blocks. High concentrations of Ca and Mg, singly or in combination, increased survival of P. multocida organisms (P < 0.001). We developed a survival index to predict whether or not specific ponds could be "problem" or "nonproblem" avian cholera sites based on concentrations of these ions in the water.

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

    SciTech Connect

    Sinclair, K.

    2001-09-18

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

  14. Development of reference antisera to enteric-origin avian viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent molecular surveys have revealed geographically distinct lineages of avian reovirus, rotavirus and astrovirus circulating in commercial poultry. To improve our understanding of enteric virus pathogenesis, specific immunological reagents are needed to detect viruses in histological samples. To ...

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

    PubMed Central

    Zhang, Guojie; Li, Cai; Li, Qiye; Li, Bo; Larkin, Denis M.; Lee, Chul; Storz, Jay F.; Antunes, Agostinho; Greenwold, Matthew J.; Meredith, Robert W.; Ödeen, Anders; Cui, Jie; Zhou, Qi; Xu, Luohao; Pan, Hailin; Wang, Zongji; Jin, Lijun; Zhang, Pei; Hu, Haofu; Yang, Wei; Hu, Jiang; Xiao, Jin; Yang, Zhikai; Liu, Yang; Xie, Qiaolin; Yu, Hao; Lian, Jinmin; Wen, Ping; Zhang, Fang; Li, Hui; Zeng, Yongli; Xiong, Zijun; Liu, Shiping; Zhou, Long; Huang, Zhiyong; An, Na; Wang, Jie; Zheng, Qiumei; Xiong, Yingqi; Wang, Guangbiao; Wang, Bo; Wang, Jingjing; Fan, Yu; da Fonseca, Rute R.; Alfaro-Núñez, Alonzo; Schubert, Mikkel; Orlando, Ludovic; Mourier, Tobias; Howard, Jason T.; Ganapathy, Ganeshkumar; Pfenning, Andreas; Whitney, Osceola; Rivas, Miriam V.; Hara, Erina; Smith, Julia; Farré, Marta; Narayan, Jitendra; Slavov, Gancho; Romanov, Michael N; Borges, Rui; Machado, João Paulo; Khan, Imran; Springer, Mark S.; Gatesy, John; Hoffmann, Federico G.; Opazo, Juan C.; Håstad, Olle; Sawyer, Roger H.; Kim, Heebal; Kim, Kyu-Won; Kim, Hyeon Jeong; Cho, Seoae; Li, Ning; Huang, Yinhua; Bruford, Michael W.; Zhan, Xiangjiang; Dixon, Andrew; Bertelsen, Mads F.; Derryberry, Elizabeth; Warren, Wesley; Wilson, Richard K; Li, Shengbin; Ray, David A.; Green, Richard E.; O’Brien, Stephen J.; Griffin, Darren; Johnson, Warren E.; Haussler, David; Ryder, Oliver A.; Willerslev, Eske; Graves, Gary R.; Alström, Per; Fjeldså, Jon; Mindell, David P.; Edwards, Scott V.; Braun, Edward L.; Rahbek, Carsten; Burt, David W.; Houde, Peter; Zhang, Yong; Yang, Huanming; Wang, Jian; Jarvis, Erich D.; Gilbert, M. Thomas P.; Wang, Jun

    2015-01-01

    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, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits. PMID:25504712

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

    NASA Astrophysics Data System (ADS)

    Iwasa, Kuni H.; Ricci, Anthony J.

    2015-12-01

    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?"

  17. Markov Chain Estimation of Avian Seasonal Fecundity, Presentation

    EPA Science Inventory

    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...

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

    PubMed

    Zhang, Guojie; Li, Cai; Li, Qiye; Li, Bo; Larkin, Denis M; Lee, Chul; Storz, Jay F; Antunes, Agostinho; Greenwold, Matthew J; Meredith, Robert W; Ödeen, Anders; Cui, Jie; Zhou, Qi; Xu, Luohao; Pan, Hailin; Wang, Zongji; Jin, Lijun; Zhang, Pei; Hu, Haofu; Yang, Wei; Hu, Jiang; Xiao, Jin; Yang, Zhikai; Liu, Yang; Xie, Qiaolin; Yu, Hao; Lian, Jinmin; Wen, Ping; Zhang, Fang; Li, Hui; Zeng, Yongli; Xiong, Zijun; Liu, Shiping; Zhou, Long; Huang, Zhiyong; An, Na; Wang, Jie; Zheng, Qiumei; Xiong, Yingqi; Wang, Guangbiao; Wang, Bo; Wang, Jingjing; Fan, Yu; da Fonseca, Rute R; Alfaro-Núñez, Alonzo; Schubert, Mikkel; Orlando, Ludovic; Mourier, Tobias; Howard, Jason T; Ganapathy, Ganeshkumar; Pfenning, Andreas; Whitney, Osceola; Rivas, Miriam V; Hara, Erina; Smith, Julia; Farré, Marta; Narayan, Jitendra; Slavov, Gancho; Romanov, Michael N; Borges, Rui; Machado, João Paulo; Khan, Imran; Springer, Mark S; Gatesy, John; Hoffmann, Federico G; Opazo, Juan C; Håstad, Olle; Sawyer, Roger H; Kim, Heebal; Kim, Kyu-Won; Kim, Hyeon Jeong; Cho, Seoae; Li, Ning; Huang, Yinhua; Bruford, Michael W; Zhan, Xiangjiang; Dixon, Andrew; Bertelsen, Mads F; Derryberry, Elizabeth; Warren, Wesley; Wilson, Richard K; Li, Shengbin; Ray, David A; Green, Richard E; O'Brien, Stephen J; Griffin, Darren; Johnson, Warren E; Haussler, David; Ryder, Oliver A; Willerslev, Eske; Graves, Gary R; Alström, Per; Fjeldså, Jon; Mindell, David P; Edwards, Scott V; Braun, Edward L; Rahbek, Carsten; Burt, David W; Houde, Peter; Zhang, Yong; Yang, Huanming; Wang, Jian; Jarvis, Erich D; Gilbert, M Thomas P; Wang, Jun

    2014-12-12

    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, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits. PMID:25504712

  19. Biological restorations using tooth fragments.

    PubMed

    Busato, A L; Loguercio, A D; Barbosa, A N; Sanseverino, M do C; Macedo, R P; Baldissera, R A

    1998-02-01

    A "biological" restoration technique using dental fragments and adhesive materials is described. These fragments were obtained from extracted human teeth which had been previously sterilized and stored in a tooth bank. The advantages are: the use of extracted teeth as restorative material, esthetics, and treatment cost. The positive sensation of having back the missing tooth was the most mentioned comment among patients. The disadvantages are: the difficulty of obtaining teeth with the needed characteristics, problems of making an indirect restoration, matching the original color, and the non-acceptance by some patients who consider it strange to have other people's teeth placed in their mouths. PMID:9823086

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

    PubMed

    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. PMID:26370196

  1. Artist conception of the Avian Development Facility

    NASA Technical Reports Server (NTRS)

    2003-01-01

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

  2. A glossary for avian conservation biology

    USGS Publications Warehouse

    Koford, Rolf R.; Dunning, J.B., Jr.; Ribic, C.A.; Finch, D.M.

    1994-01-01

    This glossary provides standard definitions for many of the terms used in avian conservation biology. We compiled these definitions to assist communication among researchers, managers, and others involved in the Neotropical Migratory Bird Conservation Program, also known as Partners in Flight. We used existing glossaries and recent literature to prepare this glossary. The cited sources were not necessarily the first ones to use the terms. Many definitions were taken verbatim from the cited source material. Others were modified slightly to clarify the meaning. Definitions that were modified to a greater extent are indicated as being adapted from the originals. Terms that have been used in more than one way by different authors are listed with numbered alternative definitions if the definitions differ substantially.

  3. Brachyspira pilosicoli-induced avian intestinal spirochaetosis

    PubMed Central

    Le Roy, Caroline I.; Mappley, Luke J.; La Ragione, Roberto M.; Woodward, Martin J.; Claus, Sandrine P.

    2015-01-01

    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. PMID:26679774

  4. Adaptation to nocturnality - learning from avian genomes.

    PubMed

    Le Duc, Diana; Schöneberg, Torsten

    2016-07-01

    The recent availability of multiple avian genomes has laid the foundation for a huge variety of comparative genomics analyses including scans for changes and signatures of selection that arose from adaptions to new ecological niches. Nocturnal adaptation in birds, unlike in mammals, is comparatively recent, a fact that makes birds good candidates for identifying early genetic changes that support adaptation to dim-light environments. In this review, we give examples of comparative genomics analyses that could shed light on mechanisms of adaptation to nocturnality. We present advantages and disadvantages of both "data-driven" and "hypothesis-driven" approaches that lead to the discovery of candidate genes and genetic changes promoting nocturnality. We anticipate that the accessibility of multiple genomes from the Genome 10K Project will allow a better understanding of evolutionary mechanisms and adaptation in general. PMID:27172298

  5. Infrasound and the avian navigational map

    USGS Publications Warehouse

    Hagstrum, J.T.

    2001-01-01

    Birds can accurately navigate over hundreds to thousands of kilometres, and use celestial and magnetic compass senses to orient their flight. How birds determine their location in order to select the correct homeward bearing (map sense) remains controversial, and has been attributed to their olfactory or magnetic senses. Pigeons can hear infrasound down to 0??05 Hz, and an acoustic avian map is proposed consisting of infrasonic cues radiated from steep-sided topographic features. The source of these infrasonic signals is microseisms continuously generated by interfering oceanic waves. Atmospheric processes affecting the infrasonic map cues can explain perplexing experimental results from pigeon releases. Moreover, four recent disrupted pigeon races in Europe and the north-eastern USA intersected infrasonic shock waves from the Concorde supersonic transport. Having an acoustic map might also allow clock-shifted birds to test their homeward progress and select between their magnetic and solar compasses.

  6. Avian ultraviolet/violet cones as magnetoreceptors

    PubMed Central

    Bischof, Hans-Joachim; Nießner, Christine; Peichl, Leo; Wiltschko, Wolfgang

    2011-01-01

    In a recent paper, we described the localization of cryptochrome 1a in the retina of domestic chickens, Gallus gallus, and European robins, Erithacus rubecula: Cryptochrome 1a was found exclusively along the membranes of the disks in the outer segments of the ultraviolet/violet single cones. Cryptochrome has been suggested to act as receptor molecule for the avian magnetic compass, which would mean that the UV/V cones have a double function: they mediate vision in the short-wavelength range and, at the same time, magnetic directional information. This has important implications and raises a number of questions, in particular, how the two types of input are separated. Here, we point out several possibilities how this could be achieved.  PMID:22446535

  7. Avian Influenza spread and transmission dynamics

    USGS Publications Warehouse

    Bourouiba, Lydia; Gourley, Stephen A.; Liu, Rongsong; Takekawa, John Y.; 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.

  8. Efficient statistical mapping of avian count data

    USGS Publications Warehouse

    Royle, J. Andrew; Wikle, C.K.

    2005-01-01

    We develop a spatial modeling framework for count data that is efficient to implement in high-dimensional prediction problems. We consider spectral parameterizations for the spatially varying mean of a Poisson model. The spectral parameterization of the spatial process is very computationally efficient, enabling effective estimation and prediction in large problems using Markov chain Monte Carlo techniques. We apply this model to creating avian relative abundance maps from North American Breeding Bird Survey (BBS) data. Variation in the ability of observers to count birds is modeled as spatially independent noise, resulting in over-dispersion relative to the Poisson assumption. This approach represents an improvement over existing approaches used for spatial modeling of BBS data which are either inefficient for continental scale modeling and prediction or fail to accommodate important distributional features of count data thus leading to inaccurate accounting of prediction uncertainty.

  9. Impacts of climate change on avian populations.

    PubMed

    Jenouvrier, Stephanie

    2013-07-01

    This review focuses on the impacts of climate change on population dynamics. I introduce the MUP (Measuring, Understanding, and Predicting) approach, which provides a general framework where an enhanced understanding of climate-population processes, along with improved long-term data, are merged into coherent projections of future population responses to climate change. This approach can be applied to any species, but this review illustrates its benefit using birds as examples. Birds are one of the best-studied groups and a large number of studies have detected climate impacts on vital rates (i.e., life history traits, such as survival, maturation, or breeding, affecting changes in population size and composition) and population abundance. These studies reveal multifaceted effects of climate with direct, indirect, time-lagged, and nonlinear effects. However, few studies integrate these effects into a climate-dependent population model to understand the respective role of climate variables and their components (mean state, variability, extreme) on population dynamics. To quantify how populations cope with climate change impacts, I introduce a new universal variable: the 'population robustness to climate change.' The comparison of such robustness, along with prospective and retrospective analysis may help to identify the major climate threats and characteristics of threatened avian species. Finally, studies projecting avian population responses to future climate change predicted by IPCC-class climate models are rare. Population projections hinge on selecting a multiclimate model ensemble at the appropriate temporal and spatial scales and integrating both radiative forcing and internal variability in climate with fully specified uncertainties in both demographic and climate processes. PMID:23505016

  10. Estimating avian population size using Bowden's estimator

    USGS Publications Warehouse

    Diefenbach, D.R.

    2009-01-01

    Avian researchers often uniquely mark birds, and multiple estimators could be used to estimate population size using individually identified birds. However, most estimators of population size require that all sightings of marked birds be uniquely identified, and many assume homogeneous detection probabilities. Bowden's estimator can incorporate sightings of marked birds that are not uniquely identified and relax assumptions required of other estimators. I used computer simulation to evaluate the performance of Bowden's estimator for situations likely to be encountered in bird studies. When the assumptions of the estimator were met, abundance and variance estimates and confidence-interval coverage were accurate. However, precision was poor for small population sizes (N ??? 50) unless a large percentage of the population was marked (>75%) and multiple (???8) sighting surveys were conducted. If additional birds are marked after sighting surveys begin, it is important to initially mark a large proportion of the population (pm ??? 0.5 if N ??? 100 or pm > 0.1 if N ??? 250) and minimize sightings in which birds are not uniquely identified; otherwise, most population estimates will be overestimated by >10%. Bowden's estimator can be useful for avian studies because birds can be resighted multiple times during a single survey, not all sightings of marked birds have to uniquely identify individuals, detection probabilities among birds can vary, and the complete study area does not have to be surveyed. I provide computer code for use with pilot data to design mark-resight surveys to meet desired precision for abundance estimates. ?? 2009 by The American Ornithologists' Union. All rights reserved.

  11. Avian rotavirus enteritis - an updated review.

    PubMed

    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. PMID:25917772

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

    PubMed Central

    Liu, Sanhong; Pang, Liuyong; Ruan, Shigui

    2015-01-01

    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. PMID:25861378

  13. Fusariotoxins in Avian Species: Toxicokinetics, Metabolism and Persistence in Tissues

    PubMed Central

    Guerre, Philippe

    2015-01-01

    Fusariotoxins are mycotoxins produced by different species of the genus Fusarium whose occurrence and toxicity vary considerably. Despite the fact avian species are highly exposed to fusariotoxins, the avian species are considered as resistant to their toxic effects, partly because of low absorption and rapid elimination, thereby reducing the risk of persistence of residues in tissues destined for human consumption. This review focuses on the main fusariotoxins deoxynivalenol, T-2 and HT-2 toxins, zearalenone and fumonisin B1 and B2. The key parameters used in the toxicokinetic studies are presented along with the factors responsible for their variations. Then, each toxin is analyzed separately. Results of studies conducted with radiolabelled toxins are compared with the more recent data obtained with HPLC/MS-MS detection. The metabolic pathways of deoxynivalenol, T-2 toxin, and zearalenone are described, with attention paid to the differences among the avian species. Although no metabolite of fumonisins has been reported in avian species, some differences in toxicokinetics have been observed. All the data reviewed suggest that the toxicokinetics of fusariotoxins in avian species differs from those in mammals, and that variations among the avian species themselves should be assessed. PMID:26110506

  14. Molecular cloning and comparison of avian preproghrelin genes.

    PubMed

    Yuan, Jing; Zhou, Jianjun; Hu, Xiaoxiang; Li, Ning

    2007-04-01

    We report cDNA sequences for the preproghrelin gene from goose, duck, and emu. This gene is involved in stimulating the release of growth hormone in mammals and may play a similar role in avian species. The complete coding sequence of avian preproghrelin encodes a 116 amino acid (aa) protein, which is organized into three parts: the N-terminal hydrophobic signal peptide, a 26 aa peptide for mature ghrelin, and a long C-terminal polypeptide. Domain/motif structures of preproghrelin protein are highly conserved among avian species. Although the avian and mammalian homologs are not highly similar for the whole 116 aa sequence, the identity of the highly conserved "active core" sequence and the n-octanoyl modification of the serine 3 residue avian ghrelin protein with its mammalian homologs implies conserved function of ghrelin protein during evolution. Information provided in this study will be useful in further studies to determine the role the preproghrelin gene plays in the regulation of growth hormone release and body weight gain in avian species. PMID:17347866

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

    PubMed Central

    Zhang, Guolong; Sunkara, Lakshmi T.

    2014-01-01

    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. PMID:24583933

  16. Nuclear energy release from fragmentation

    NASA Astrophysics Data System (ADS)

    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.

  17. Percolative fragmentation and spontaneous agglomeration

    SciTech Connect

    Hurt, R.; Davis, K.

    1999-03-01

    Captive particle imaging experiments were performed on over 200 coal and char particles in the pulverized size range from four coals of various rank at oxygen concentration from 3--19 mol% and at gas temperatures of about 1250 K. Despite wide variations in single-particle behavior, the data set reveals two clear trends that provide new information on the nature of char combustion. First, the low-rank coal chars are observed to maintain their high reactivity through the late stages of combustion, thus avoiding the near-extinction events and long burnout tails observed for bituminous coal chars. Secondly, percolative fragmentation in the late stages of combustion is a rare event under these conditions. Some particles reach a percolation threshold rate in combustion, but typically undergo spontaneous agglomeration rather than liberation of the incipient fragments. It is concluded that percolative fragmentation behavior in the pulverized size range is determined not only by solid-phase connectivity, but also by a real competition between disruptive and cohesive forces present at the time of formation of the colloidal-sized incipient fragments.

  18. Fission fragment driven neutron source

    DOEpatents

    Miller, Lowell G.; Young, Robert C.; Brugger, Robert M.

    1976-01-01

    Fissionable uranium formed into a foil is bombarded with thermal neutrons in the presence of deuterium-tritium gas. The resulting fission fragments impart energy to accelerate deuterium and tritium particles which in turn provide approximately 14 MeV neutrons by the reactions t(d,n).sup.4 He and d(t,n).sup.4 He.

  19. Economical technique for fragmentation testing

    NASA Technical Reports Server (NTRS)

    Smith, T. H., III; Snoke, B. A.

    1974-01-01

    Automatic rifle was modified for remote, single-shot use. To simulate statistically--determined fragment size from rocket-motor casing blunt-nosed bullet was made of same alloy. Cartridge was loaded with enough powder to make bullet reach target at same estimated velocity as shrapnel from rocket casing.

  20. Fragmentation in the First Galaxies

    NASA Astrophysics Data System (ADS)

    Safranek-Shrader, Chalence; Bromm, Volker; Milosavljević, Miloš

    2010-11-01

    Motivated by recent simulations of galaxy formation in which protogalaxies acquire their baryonic content through cold accretion, we study the gravitational fragmentation of cold streams flowing into a typical first galaxy. We use a one-zone hydrodynamical model to examine the thermal evolution of the gas flowing into a 108 M sun dark matter halo at redshift z = 10. The goal is to gain an understanding of the expected fragmentation mass scale and thus the characteristic mass of the first population of stars to form by shock fragmentation. Our model accurately describes the chemical and thermal evolution of the gas as we are specifically concerned with how the chemical abundances and initial conditions of the low-density, metal-enriched, cold accretion streams that pass an accretion shock alter the cooling properties and tendency to fragment in the post-shock gas. Cold accretion flows are not shock heated at the virial radius but instead flow along high-baryonic-density filaments of the cosmic web and penetrate deep into the host halo of the protogalaxy. In this physical regime, if molecular cooling is absent because of a strong Lyman-Werner background, we find there to be a sharp drop in the fragmentation mass at a metallicity of Z ~ 10-4 Z sun. If, however, H2 and HD molecules are present, they dominate the cooling at T < 104 K, and metallicity then has no effect on the fragmentation properties of the cold stream. For a solar abundance pattern of metallicity, O is the most effective metal coolant throughout the evolution, while for a pair instability supernova (PISN) metallicity yield, Si+ is the most effective coolant. PISN abundance patterns also exhibit a slightly smaller critical metallicity. Dust grains are not included in our chemical model, but we argue that their inclusion would not significantly alter the results. We also find that this physical scenario allows for the formation of stellar clusters and large, 104 M sun bound fragments, possibly the

  1. FRAGMENTATION IN THE FIRST GALAXIES

    SciTech Connect

    Safranek-Shrader, Chalence; Bromm, Volker; Milosavljevic, Milos

    2010-11-10

    Motivated by recent simulations of galaxy formation in which protogalaxies acquire their baryonic content through cold accretion, we study the gravitational fragmentation of cold streams flowing into a typical first galaxy. We use a one-zone hydrodynamical model to examine the thermal evolution of the gas flowing into a 10{sup 8} M{sub sun} dark matter halo at redshift z = 10. The goal is to gain an understanding of the expected fragmentation mass scale and thus the characteristic mass of the first population of stars to form by shock fragmentation. Our model accurately describes the chemical and thermal evolution of the gas as we are specifically concerned with how the chemical abundances and initial conditions of the low-density, metal-enriched, cold accretion streams that pass an accretion shock alter the cooling properties and tendency to fragment in the post-shock gas. Cold accretion flows are not shock heated at the virial radius but instead flow along high-baryonic-density filaments of the cosmic web and penetrate deep into the host halo of the protogalaxy. In this physical regime, if molecular cooling is absent because of a strong Lyman-Werner background, we find there to be a sharp drop in the fragmentation mass at a metallicity of Z {approx} 10{sup -4} Z{sub sun}. If, however, H{sub 2} and HD molecules are present, they dominate the cooling at T < 10{sup 4} K, and metallicity then has no effect on the fragmentation properties of the cold stream. For a solar abundance pattern of metallicity, O is the most effective metal coolant throughout the evolution, while for a pair instability supernova (PISN) metallicity yield, Si{sup +} is the most effective coolant. PISN abundance patterns also exhibit a slightly smaller critical metallicity. Dust grains are not included in our chemical model, but we argue that their inclusion would not significantly alter the results. We also find that this physical scenario allows for the formation of stellar clusters and large

  2. Fragments

    ERIC Educational Resources Information Center

    Moreira, Claudio

    2008-01-01

    This performance autoethnography shows the author's struggle in finding his place, scholarship, voice, and body, into the academic setting. Mixing together memories of his lived experience with sugar cane workers, notes, and leftovers of different fieldworks, plus 6 years of life as grad student at the University of Illinois, the author looks for…

  3. Energy production using fission fragment rockets

    NASA Astrophysics Data System (ADS)

    Chapline, G.; Matsuda, Y.

    1991-08-01

    Fission fragment rockets are nuclear reactors with a core consisting of thin fibers in a vacuum, and which use magnetic fields to extract the fission fragments from the reactor core. As an alternative to ordinary nuclear reactors, fission fragment rockets would have the following advantages: approximately twice the efficiency if the fission fragment energy can be directly converted into electricity; reduction of the buildup of a fission fragment inventory in the reactor could avoid a Chernobyl type disaster; and collection of the fission fragments outside the reactor could simplify the waste disposal problem.

  4. A Complete Molecular Diagnostic Procedure for Applications in Surveillance and Subtyping of Avian Influenza Virus

    PubMed Central

    Tseng, Chun-Hsien; Tsai, Hsiang-Jung; Chang, Chung-Ming

    2014-01-01

    Introduction. The following complete molecular diagnostic procedure we developed, based on real-time quantitative PCR and traditional PCR, is effective for avian influenza surveillance, virus subtyping, and viral genome sequencing. Method. This study provides a specific and sensitive step-by-step procedure for efficient avian influenza identification of 16 hemagglutinin and 9 neuraminidase avian influenza subtypes. Result and Conclusion. This diagnostic procedure may prove exceedingly useful for virological and ecological advancements in global avian influenza research. PMID:25057497

  5. Workflow Design Using Fragment Composition

    NASA Astrophysics Data System (ADS)

    Mosser, Sébastien; Blay-Fornarino, Mireille; France, Robert

    The Service-Oriented Architecture (Soa) paradigm supports the assembly of atomic services to create applications that implement complex business processes. Assembly can be accomplished by service orchestrations defined by Soa architects. The Adore method allows Soa architects to model complex orchestrations of services by composing models of smaller orchestrations called orchestration fragments. The Adore method can also be used to weave fragments that address new concerns into existing application models. In this paper we illustrate how the Adore method can be used to separate and compose process aspects in a Soa design of the Car Crash Crisis Management System. The paper also includes a discussion of the benefits and limitations of the Adore method.

  6. Fragmentation of the Chelyabinsk Fireball

    NASA Astrophysics Data System (ADS)

    Melosh, J.

    2013-12-01

    The most intense bolide since the 1908 Tunguska event occurred in the early morning hours of 15 February 2013 near the Russian town of Chelyabinsk. The impacting asteroid ranged between 17 and 20 m diameter with a mass of about 10,000 tons. Its estimated pre-atmospheric velocity was about 18.6 km/sec at a low angle of 20° from the horizontal. The resulting airburst occurred at an altitude of about 23 km and released an estimated total energy of about 440 kT (1.7 x 1015 J). The blast wave shattered windows on the ground over a wide area and collapsed the roof of a zinc factory. In spite of the size of the initital asteroid, only small fragments (a few kg, so far) have been recovered. The entry of an asteroid into Earth's atmosphere and its aerodynamic fragmentation and deceleration has been modeled by a number of authors over the past few decades. Full-featured numerical simulations are presently limited in their ability to simultaneously incorporate fragmentation, energy coupling between solid fragments and the atmosphere, and thermal radiation, but an approximate treatment of the fragmentation and dispersion of a large entering meteoroid called the 'pancake model' has achieved good fits to other observed events, including the Tunguska explosion, the 1947 Shikote-Alin fall and strewn fields from larger iron meteorite falls, such as the Henbury craters. Simulations using the pancake model can fit the overall observations of the Chelyabinsk event using an 18 m diameter asteroid of density 3000 kg/m3 following the observed trajectory and possessing an initial strength of about 7 MPa, which is relatively high for a stony meteoroid. This suggests that the asteroid was not a strengthless rubble pile, but in fact possessed considerable strength, compared to other stony meteorites of similar type. Aerodynamic breakup begins at an altitude of 31 km and the final airburst occurs at 22 km, releasing about 250 kT at this time. Subsequent to this airburst, large fragments

  7. Asymmetry effects in fragment production

    NASA Astrophysics Data System (ADS)

    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).

  8. Golgi fragmentation in Alzheimer's disease

    PubMed Central

    Joshi, Gunjan; Bekier, Michael E.; Wang, Yanzhuang

    2015-01-01

    The Golgi apparatus is an essential cellular organelle for post-translational modifications, sorting, and trafficking of membrane and secretory proteins. Proper functionality of the Golgi requires the formation of its unique cisternal-stacking morphology. The Golgi structure is disrupted in a variety of neurodegenerative diseases, suggesting a common mechanism and contribution of Golgi defects in neurodegenerative disorders. A recent study on Alzheimer's disease (AD) revealed that phosphorylation of the Golgi stacking protein GRASP65 disrupts its function in Golgi structure formation, resulting in Golgi fragmentation. Inhibiting GRASP65 phosphorylation restores the Golgi morphology from Aβ-induced fragmentation and reduces Aβ production. Perturbing Golgi structure and function in neurons may directly impact trafficking, processing, and sorting of a variety of proteins essential for synaptic and dendritic integrity. Therefore, Golgi defects may ultimately promote the development of AD. In the current review, we focus on the cellular impact of impaired Golgi morphology and its potential relationship to AD disease development. PMID:26441511

  9. Fragmentation of suddenly heated liquids

    SciTech Connect

    Blink, J.A.

    1985-03-01

    Fragmentation of free liquids in Inertial Confinement Fusion reactors could determine the upper bound on reactor pulse rate. The x-ray ablated materials must cool and recondense to allow driver beam propagation. The increased surface area caused by fragmentation will enhance the cooling and condensation rates. Relaxation from the suddenly heated state will move a liquid into the negative pressure region under the liquid-vapor P-V dome. The lithium equation of state was used to demonstrate that neutron-induced vaporization uses only a minor fraction of the added heat, much less than would be required to drive the expansion. A 77% expansion of the lithium is required before the rapid vaporization process of spinodal decomposition could begin, and nucleation and growth are too slow to contribute to the expansion.

  10. The fragmentation of Kosmos 2163

    NASA Technical Reports Server (NTRS)

    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.

  11. Telomere Restriction Fragment (TRF) Analysis

    PubMed Central

    Mender, Ilgen; Shay, Jerry W.

    2016-01-01

    While telomerase is expressed in ~90% of primary human tumors, most somatic tissue cells except transiently proliferating stem-like cells do not have detectable telomerase activity (Shay and Wright, 1996; Shay and Wright, 2001). Telomeres progressively shorten with each cell division in normal cells, including proliferating stem-like cells, due to the end replication (lagging strand synthesis) problem and other causes such as oxidative damage, therefore all somatic cells have limited cell proliferation capacity (Hayflick limit) (Hayflick and Moorhead, 1961; Olovnikov, 1973). The progressive telomere shortening eventually leads to growth arrest in normal cells, which is known as replicative senescence (Shay et al., 1991). Once telomerase is activated in cancer cells, telomere length is stabilized by the addition of TTAGGG repeats to the end of chromosomes, thus enabling the limitless continuation of cell division (Shay and Wright, 1996; Shay and Wright, 2001). Therefore, the link between aging and cancer can be partially explained by telomere biology. There are many rapid and convenient methods to study telomere biology such as Telomere Restriction Fragment (TRF), Telomere Repeat Amplification Protocol (TRAP) (Mender and Shay, 2015b) and Telomere dysfunction Induced Foci (TIF) analysis (Mender and Shay, 2015a). In this protocol paper we describe Telomere Restriction Fragment (TRF) analysis to determine average telomeric length of cells. Telomeric length can be indirectly measured by a technique called Telomere Restriction Fragment analysis (TRF). This technique is a modified Southern blot, which measures the heterogeneous range of telomere lengths in a cell population using the length distribution of the terminal restriction fragments (Harley et al., 1990; Ouellette et al., 2000). This method can be used in eukaryotic cells. The description below focuses on the measurement of human cancer cells telomere length. The principle of this method relies on the lack of

  12. Modeling of Fragmentation of Asteroids

    NASA Technical Reports Server (NTRS)

    Agrawal, Parul; Prabhu, Dinesh K.; Carlozzi, Alexander; Hart, Kenneth; Bryson, Katie; Sears, Derek

    2015-01-01

    The objective of this study is to understand fragmentation and fracture of a given asteroid and mechanisms of break-up. The focus of the present work is to develop modeling techniques for stony asteroids in 10m-100m range to answer two questions: 1) What is the role of material makeup of an asteroid in the stress distribution? 2)How is stress distribution altered in the presence of pre-existing defects?

  13. HCD Fragmentation of Glycated Peptides.

    PubMed

    Keilhauer, Eva C; Geyer, Philipp E; Mann, Matthias

    2016-08-01

    Protein glycation is a concentration-dependent nonenzymatic reaction of reducing sugars with amine groups of proteins to form early as well as advanced glycation (end-) products (AGEs). Glycation is a highly disease-relevant modification but is typically only studied on a few blood proteins. To complement our blood proteomics studies in diabetics, we here investigate protein glycation by higher energy collisional dissociation (HCD) fragmentation on Orbitrap mass spectrometers. We established parameters to most efficiently fragment and identify early glycation products on in vitro glycated model proteins. Retaining standard collision energies does not degrade performance if the most dominant neutral loss of H6O3 is included into the database search strategy. Glycation analysis of the entire HeLa proteome revealed an unexpected intracellular preponderance for arginine over lysine modification in early and advanced glycation (end-) products. Single-run analysis from 1 μL of undepleted and unenriched blood plasma identified 101 early glycation sites as well as numerous AGE sites on diverse plasma proteins. We conclude that HCD fragmentation is well-suited for analyzing glycated peptides and that the diabetic status of patients can be directly diagnosed from single-run plasma proteomics measurements. PMID:27425404

  14. H5N1 Avian Flu (H5N1 Bird Flu)

    MedlinePlus

    ... H5N1 - Avian/Bird Flu H5N1 Avian Flu - H5N1 Bird Flu H5N1 is a highly pathogenic avian (bird) flu virus that has caused serious outbreaks in ... been no reported infections with these viruses in birds, poultry, or people in the United States. You ...

  15. Scientific basis for use of vaccination as a strategy to control avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines have been used to control a variety of piscian, avian, and mammalian diseases. Commercial usage of vaccines against avian influenza (AI) began in 1979, in Minnesota to control H4 and H6 low pathogenicity avian influenza (LPAI) which was causing economically significant disease in turkey br...

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

    Federal Register 2010, 2011, 2012, 2013, 2014

    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. Influence of interspecific competition and landscape structure on spatial homogenization of avian assemblages.

    PubMed

    Robertson, Oliver J; McAlpine, Clive; House, Alan; Maron, Martine

    2013-01-01

    Human-induced biotic homogenization resulting from landscape change and increased competition from widespread generalists or 'winners', is widely recognized as a global threat to biodiversity. However, it remains unclear what aspects of landscape structure influence homogenization. This paper tests the importance of interspecific competition and landscape structure, for the spatial homogeneity of avian assemblages within a fragmented agricultural landscape of eastern Australia. We used field observations of the density of 128 diurnal bird species to calculate taxonomic and functional similarity among assemblages. We then examined whether taxonomic and functional similarity varied with patch type, the extent of woodland habitat, land-use intensity, habitat subdivision, and the presence of Manorina colonies (a competitive genus of honeyeaters). We found the presence of a Manorina colony was the most significant factor positively influencing both taxonomic and functional similarity of bird assemblages. Competition from members of this widespread genus of native honeyeater, rather than landscape structure, was the main cause of both taxonomic and functional homogenization. These species have not recently expanded their range, but rather have increased in density in response to agricultural landscape change. The negative impacts of Manorina honeyeaters on assemblage similarity were most pronounced in landscapes of moderate land-use intensity. We conclude that in these human-modified landscapes, increased competition from dominant native species, or 'winners', can result in homogeneous avian assemblages and the loss of specialist species. These interacting processes make biotic homogenization resulting from land-use change a global threat to biodiversity in modified agro-ecosystems. PMID:23724136

  18. Influence of Interspecific Competition and Landscape Structure on Spatial Homogenization of Avian Assemblages

    PubMed Central

    Robertson, Oliver J.; McAlpine, Clive; House, Alan; Maron, Martine

    2013-01-01

    Human-induced biotic homogenization resulting from landscape change and increased competition from widespread generalists or ‘winners’, is widely recognized as a global threat to biodiversity. However, it remains unclear what aspects of landscape structure influence homogenization. This paper tests the importance of interspecific competition and landscape structure, for the spatial homogeneity of avian assemblages within a fragmented agricultural landscape of eastern Australia. We used field observations of the density of 128 diurnal bird species to calculate taxonomic and functional similarity among assemblages. We then examined whether taxonomic and functional similarity varied with patch type, the extent of woodland habitat, land-use intensity, habitat subdivision, and the presence of Manorina colonies (a competitive genus of honeyeaters). We found the presence of a Manorina colony was the most significant factor positively influencing both taxonomic and functional similarity of bird assemblages. Competition from members of this widespread genus of native honeyeater, rather than landscape structure, was the main cause of both taxonomic and functional homogenization. These species have not recently expanded their range, but rather have increased in density in response to agricultural landscape change. The negative impacts of Manorina honeyeaters on assemblage similarity were most pronounced in landscapes of moderate land-use intensity. We conclude that in these human-modified landscapes, increased competition from dominant native species, or ‘winners’, can result in homogeneous avian assemblages and the loss of specialist species. These interacting processes make biotic homogenization resulting from land-use change a global threat to biodiversity in modified agro-ecosystems. PMID:23724136

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

    PubMed Central

    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. PMID:26191057

  20. Next generation sequencing technologies: tool to study avian virus diversity.

    PubMed

    Kapgate, S S; Barbuddhe, S B; Kumanan, K

    2015-03-01

    Increased globalisation, climatic changes and wildlife-livestock interface led to emergence of novel viral pathogens or zoonoses that have become serious concern to avian, animal and human health. High biodiversity and bird migration facilitate spread of the pathogen and provide reservoirs for emerging infectious diseases. Current classical diagnostic methods designed to be virus-specific or aim to be limited to group of viral agents, hinder identifying of novel viruses or viral variants. Recently developed approaches of next-generation sequencing (NGS) provide culture-independent methods that are useful for understanding viral diversity and discovery of novel virus, thereby enabling a better diagnosis and disease control. This review discusses the different possible steps of a NGS study utilizing sequence-independent amplification, high-throughput sequencing and bioinformatics approaches to identify novel avian viruses and their diversity. NGS lead to the identification of a wide range of new viruses such as picobirnavirus, picornavirus, orthoreovirus and avian gamma coronavirus associated with fulminating disease in guinea fowl and is also used in describing viral diversity among avian species. The review also briefly discusses areas of viral-host interaction and disease associated causalities with newly identified avian viruses. PMID:25790045

  1. Evidence of previous avian influenza infection among US turkey workers.

    PubMed

    Kayali, G; Ortiz, E J; Chorazy, M L; Gray, G C

    2010-06-01

    The threat of an influenza pandemic is looming, with new cases of sporadic avian influenza infections in man frequently reported. Exposure to diseased poultry is a leading risk factor for these infections. In this study, we used logistic regression to investigate serological evidence of previous infection with avian influenza subtypes H4, H5, H6, H7, H8, H9, H10, and H11 among 95 adults occupationally exposed to turkeys in the US Midwest and 82 unexposed controls. Our results indicate that farmers practising backyard, organic or free-ranging turkey production methods are at an increased risk of infection with avian influenza. Among these farmers, the adjusted odds ratios (ORs) for elevated microneutralization assay titres against avian H4, H5, H6, H9, and H10 influenza strains ranged between 3.9 (95% CI 1.2-12.8) and 15.3 (95% CI 2.0-115.2) when compared to non-exposed controls. The measured ORs were adjusted for antibody titres against human influenza viruses and other exposure variables. These data suggest that sometime in their lives, the workers had been exposed to low pathogenicity avian influenza viruses. These findings support calls for inclusion of agricultural workers in priority groups in pandemic influenza preparedness efforts. These data further support increasing surveillance and other preparedness efforts to include not only confinement poultry facilities, but more importantly, also small scale farms. PMID:19486492

  2. Radical-pair based avian magnetoreception

    NASA Astrophysics Data System (ADS)

    Procopio, Maria; Ritz, Thorsten

    2014-03-01

    Behavioural experiments suggest that migratory birds possess a magnetic compass sensor able to detect the direction of the geomagnetic. One hypothesis for the basis of this remarkable sensory ability is that the coherent quantum spin dynamics of photoinduced radical pair reactions transduces directional magnetic information from the geomagnetic field into changes of reaction yields, possibly involving the photoreceptor cryptochrome in the birds retina. The suggested radical-pair based avian magnetoreception has attracted attention in the field of quantum biology as an example of a biological sensor which might exploit quantum coherences for its biological function. Investigations on such a spin-based sensor have focussed on uncovering the design features for the design of a biomimetic magnetic field sensor. We study the effects of slow fluctuations in the nuclear spin environment on the directional signal. We quantitatively evaluate the robustness of signals under fluctuations on a timescale longer than the lifetime of a radical pair, utilizing two models of radical pairs. Our results suggest design principles for building a radical-pair based compass sensor that is both robust and highly directional sensitive.

  3. Fossil avian eggshell preserves ancient DNA

    PubMed Central

    Oskam, Charlotte L.; Haile, James; McLay, Emma; Rigby, Paul; Allentoft, Morten E.; Olsen, Maia E.; Bengtsson, Camilla; Miller, Gifford H.; Schwenninger, Jean-Luc; Jacomb, Chris; Walter, Richard; Baynes, Alexander; Dortch, Joe; Parker-Pearson, Michael; Gilbert, M. Thomas P.; Holdaway, Richard N.; Willerslev, Eske; Bunce, Michael

    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 isolation and amplification of DNA from fossil eggshell up to 19 ka old. aDNA was successfully characterized from eggshell obtained from New Zealand (extinct moa and ducks), Madagascar (extinct elephant birds) and Australia (emu and owl). Our data demonstrate excellent preservation of the nucleic acids, evidenced by retrieval of both mitochondrial and nuclear DNA from many of the samples. Using confocal microscopy and quantitative PCR, this study critically evaluates approaches to maximize DNA recovery from powdered eggshell. Our quantitative PCR experiments also demonstrate that moa eggshell has approximately 125 times lower bacterial load than bone, making it a highly suitable substrate for high-throughput sequencing approaches. Importantly, the preservation of DNA in Pleistocene eggshell from Australia and Holocene deposits from Madagascar indicates that eggshell is an excellent substrate for the long-term preservation of DNA in warmer climates. The successful recovery of DNA from this substrate has implications in a number of scientific disciplines; most notably archaeology and palaeontology, where genotypes and/or DNA-based species identifications can add significantly to our understanding of diets, environments, past biodiversity and evolutionary processes. PMID:20219731

  4. Avian leucocyte counting using the hemocytometer

    USGS Publications Warehouse

    Dein, F.J.; Wilson, A.; Fischer, D.; Langenberg, P.

    1994-01-01

    Automated methods for counting leucocytes in avian blood are not available because of the presence of nucleated erythrocytes and thrombocytes. Therefore, total white blood cell counts are performed by hand using a hemocytometer. The Natt and Herrick and the Unopette methods are the most common stain and diluent preparations for this procedure. Replicate hemocytometer counts using these two methods were performed on blood from four birds of different species. Cells present in each square of the hemocytometer were counted. Counting cells in the corner, side, or center hemocytometer squares produced statistically equivalent results; counting four squares per chamber provided a result similar to that obtained by counting nine squares; and the Unopette method was more precise for hemocytometer counting than was the Natt and Herrick method. The Unopette method is easier to learn and perform but is an indirect process, utilizing the differential count from a stained smear. The Natt and Herrick method is a direct total count, but cell identification is more difficult.

  5. Worldwide phylogenetic relationship of avian poxviruses

    USGS Publications Warehouse

    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.

  6. Avian endocrine responses to environmental pollutants

    SciTech Connect

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

    1984-12-01

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

  7. Avian Blood-Vessel Formation in Space

    NASA Technical Reports Server (NTRS)

    Lelkes, Peter I.

    1999-01-01

    Based on previous studies, we hypothesized that the developmental anomalies observed in the past might be related to or caused by delayed or improper vascular development. The objective of our research is to test the hypothesis that exposure to microgravity during space flight cause delayed or improper vascular development during embryogenesis. The effects of microgravity on the time course and extent of avian blood-vessel formation are assessed using two models, one for angiogenesis and one for vasculogenesis. The methodological approach is dictated by the constraints of the tissue preservation method used in space. Thus, both in the chorioallantoic membrane (CAM) and in the adrenal, we will evaluate microscopically the vascular architecture and immunostain endothelial cells with specific antibodies (anti- vWF and QH1). The extent of ECM protein deposition will be assessed by immunohistochemistry and correlated with the degree of vascularization, using computer-based image analysis. Also, the cellular source for ECM proteins will be assessed by in situ hybridization.

  8. Hemodynamic Patterning of the Avian Atrioventricular Valve

    PubMed Central

    Yalcin, Huseyin C.; Shekhar, Akshay; McQuinn, Tim C.; Butcher, Jonathan T.

    2011-01-01

    In this study, we develop an innovative approach to rigorously quantify the evolving hemodynamic environment of the atrioventricular (AV) canal of avian embryos. Ultrasound generated velocity profiles were imported into Micro-Computed Tomography generated anatomically precise cardiac geometries between Hamburger-Hamilton (HH) stages 17 and 30. Computational fluid dynamic simulations were then conducted and iterated until results mimicked in vivo observations. Blood flow in tubular hearts (HH17) was laminar with parallel streamlines, but strong vortices developed simultaneous with expansion of the cushions and septal walls. For all investigated stages, highest wall shear stresses (WSS) are localized to AV canal valve forming regions. Peak WSS increased from 19.34 dynes/cm2 at HH17 to 287.18 dynes/cm2 at HH30, but spatiotemporally averaged WSS became 3.62 dynes/cm2 for HH17 to 9.11 dynes/cm2 for HH30. Hemodynamic changes often preceded and correlated with morphological changes. These results establish a quantitative baseline supporting future hemodynamic analyses and interpretations. PMID:21181939

  9. Avian flu and possible human pandemic.

    PubMed

    Lahariya, Chandrakant; Sharma, A K; Pradhan, S K

    2006-04-01

    Avian flu is affecting the poultry animals world over since first outbreak in 1997 in Hong Kong and has resulted in 92 human deaths and culling of more than 150 million poultry animals in Asia and Europe. The loss to the economy has also been enormous. 13 new countries, including India, reported occurrence of the disease in poultry animals in February 2006 only, to the World Health Organisation. This rapid rate of spread of virus along with notoriety of the virus for frequent genetic re-assortment, which might enable H5N1 to infect human beings, threatens of possible influenza pandemic since the last pandemic in 1968. The human influenza caused by this subtype of the virus (H5N1) has high case fatality of 54% and majority of affected humans are between the age of 5 to 23 years. Lack of effective vaccine, poor knowledge about treatment, and with scarcity of public health measures in developing countries are major causes of concern. The real threat of impending pandemic can be avoided only if we act immediately on the basis of currently available source of information and apply scientific knowledge rationally for containment and prevention of bird flu and treat human cases promptly. PMID:16651670

  10. Worldwide Phylogenetic Relationship of Avian Poxviruses

    PubMed Central

    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 the Avipoxvirus genus has traditionally relied on one gene region (4b core protein). In this study we 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. PMID:23408635

  11. Avian endocrine responses to environmental pollutants

    USGS Publications Warehouse

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

    1984-01-01

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

  12. Serological survey of avian influenza virus infection in non-avian wildlife in Xinjiang, China.

    PubMed

    Wei, Yu-Rong; Yang, Xue-Yun; Li, Yuan-Guo; Wei, Jie; Ma, Wen-Ge; Ren, Zhi-Guang; Guo, Hui-Ling; Wang, Tie-Cheng; Mi, Xiao-Yun; Adili, Gulizhati; Miao, Shu-Kui; Shaha, Ayiqiaolifan; Gao, Yu-Wei; Huang, Jiong; Xia, Xian-Zhu

    2016-04-01

    We conducted a serological survey to detect antibodies against avian influenza virus (AIV) in Gazella subgutturosa, Canis lupus, Capreolus pygargus, Sus scrofa, Cervus elaphus, Capra ibex, Ovis ammon, Bos grunniens and Pseudois nayaur in Xinjiang, China. Two hundred forty-six sera collected from 2009 to 2013 were assayed for antibodies against H5, H7 and H9 AIVs using hemagglutination inhibition (HI) tests and a pan-influenza competitive ELISA. Across all tested wildlife species, 4.47 % harbored anti-AIV antibodies that were detected by the HI assay. The seroprevalence for each AIV subtype across all species evaluated was 0 % for H5 AIV, 0.81 % for H7 AIV, and 3.66 % for H9 AIV. H7-reactive antibodies were found in Canis lupus (9.09 %) and Ovis ammon (4.55 %). H9-reactive antibodies were found in Gazella subgutturosa (4.55 %), Canis lupus (27.27 %), Pseudois nayaur (23.08 %), and Ovis ammon (4.55 %). The pan-influenza competitive ELISA results closely corresponded to the cumulative prevalence of AIV exposure as measured by subtype-specific HI assays, suggesting that H7 and H9 AIV subtypes predominate in the wildlife species evaluated. These data provide evidence of prior infection with H7 and H9 AIVs in non-avian wildlife in Xinjiang, China. PMID:26733295

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

    PubMed Central

    Kaplan, Bryan S.; Webby, Richard J.

    2013-01-01

    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. PMID:24025480

  14. A relationship between avian carcasses and living invertebrates in the epizootiology of avian botulism

    USGS Publications Warehouse

    Duncan, R.M.; Jensen, Wayne I.

    1976-01-01

    A survey of the sources of Clostridium botulinum type C toxin possibly utilized as food by aquatic birds in an epizootic area of avian botulism in northern Utah showed that living aquatic and terrestrial invertebrates normally found in close association with dead, decomposing birds commonly carried the toxin. Of 461 samples associated with 21 species of avian carcasses, 198 were toxin-positive. Invertebrate species not normally scavengers of vertebrate tissues were less commonly and less highly toxic, particularly when captured 30 cm or more from a carcass; six of 237 samples of such aquatic invertebrates low-level toxin. Of the species tested, blow fly larvae (Calliphoridae) were the most consistently and highly toxic, although others, particularly adult and larval stages of several species of beetles (Coleoptera), contained toxin at levels probably significant in the epizootiology of the disease. An estimated 0.05 to 0.25 g of the most toxic fly larvae or 15 g of the most toxic beetles tested carried a mediam lethal dose for an adult mallard duck. Examination of stomach contents of aquatic birds dead of botulism showed that some had consumed invertebrates.

  15. Fragmentation of cosmic-string loops

    NASA Technical Reports Server (NTRS)

    York, Thomas

    1989-01-01

    The fragmentation of cosmic string loops is discussed, and the results of a simulation of this process are presented. The simulation can evolve any of a large class of loops essentially exactly, including allowing fragments that collide to join together. Such reconnection enhances the production of small fragments, but not drastically. With or without reconnections, the fragmentation process produces a collection of nonself-intersecting loops whose typical length is on the order of the persistence length of the initial loop.

  16. Comparison of calculations of fragment production

    SciTech Connect

    Canavan, G.H.

    1998-01-01

    This note compares estimates of fragment production rates in debris collisions through calculations performed with consistent debris distribution functions implicit in integrated collision frequencies provided by Attachment A. Differences between estimates of fragment production rates in space debris collisions are shown to be due primarily to different choices of the exponent in the fragment production function and the distinction between catastrophic and all collisions. Sensitivity to the fragment production parameter over the range of values consistent with experimental data is discussed.

  17. Bimodal Behavior of the Heaviest Fragment Distribution in Projectile Fragmentation

    SciTech Connect

    Bonnet, E.; Borderie, B.; Rivet, M. F.; Dayras, R.; Gagnon-Moisan, F.; Guinet, D.; Lautesse, P.; Parlog, M.; Rosato, E.; Vigilante, M.

    2009-08-14

    The charge distribution of the heaviest fragment detected in the decay of quasiprojectiles produced in intermediate energy heavy-ion collisions has been observed to be bimodal. This feature is expected as a generic signal of phase transition in nonextensive systems. In this Letter, we present new analyses of experimental data from Au on Au collisions at 60, 80, and 100 MeV/nucleon showing that bimodality is largely independent of the data selection procedure and of entrance channel effects. An estimate of the latent heat of the transition is extracted.

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

    PubMed

    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. PMID:27610734

  19. Interactive mechanism between avian infectious bronchitis S1 protein T cell peptide and avian MHC I molecule.

    PubMed

    Zhu, Feng-Zhu; Lu, Mei; Huang, Qing-Hua; Huang, Yan-Yan; Yang, Shao-Hua; Cui, Yan-Shun; Liu, Chang; Tan, Liugang; Kong, Zhengjie; Xu, Chuan-Tian

    2016-04-01

    This study aims to construct a 3D structure of the avian major histocompatibility complex (MHC)-β2M complex through homology modelling technology, perform molecular docking of the predicted infectious bronchitis virus (IBV) S1 protein potential epitope peptide Sp6 (NQFYIKLT) and the avian MHC-β2M complex, and demonstrate the interactive mechanism between Sp6 and MHC using molecular dynamical simulations. The peptide Sp6 and the non-related peptide NP89-97 (PKKTGGPIY) were used to stimulate in vitro recombinant plasmid (pCAGGS-S1) avian splenic lymphocytes. Flow cytometric results show that CD8(+) T lymphocytes reproduce stimulated by the Sp6 and the nonrelated peptide proliferate by 34.8% and 2.6%, respectively. Meanwhile, fluorescent quantitative PCR results show that the secretion of IFN-γ in avian splenic lymphocytes increases after Sp6 stimulation. These data suggest that Sp6 can induce the activated avian lymphocytes in vitro to produce CTL, which is the CTL epitope in IBV S1. PMID:26876645

  20. ABCD: a functional database for the avian brain.

    PubMed

    Schrott, Aniko; Kabai, Peter

    2008-01-30

    Here we present the first database developed for storing, retrieving and cross-referencing neuroscience information about the connectivity of the avian brain. The Avian Brain Circuitry Database (ABCD) contains entries about the new and old terminology of the areas and their hierarchy, data on connections between brain regions, as well as a functional keyword system linked to brain regions and connections. Data were collected from the primary literature and textbooks, and an online submission system was developed to facilitate further data collection directly from researchers. The database aims to help spread the results of avian connectivity studies, the recently revised nomenclature and also to provide data for brain network research. ABCD is freely available at http://www.behav.org/abcd. PMID:17889371

  1. International standards for the control of avian influenza.

    PubMed

    Pearson, J E

    2003-01-01

    The Office International des Epizooties (OIE) has developed international standards to reduce the risk of the spread of high-pathogenicity avian influenza though international trade. These standards include providing a definition of high-pathogenicity avian influenza (HPAI), procedures for prompt reporting of HPAI outbreaks, requirements that must be met for a country or zone to be defined as free of HPAI, requirements that should be met to import live birds and avian products into a HPAI-free country or zone, and the general provisions that countries should meet to reduce the risk of spread of HPAI through trade. The goal of these standards is to facilitate trade while minimizing the risk of the introduction of HPAI. PMID:14575096

  2. Avians as a model system of vascular development.

    PubMed

    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. PMID:25468608

  3. Predictive model of avian electrocution risk on overhead power lines.

    PubMed

    Dwyer, J F; Harness, R E; Donohue, K

    2014-02-01

    Electrocution on overhead power structures negatively affects avian populations in diverse ecosystems worldwide, contributes to the endangerment of raptor populations in Europe and Africa, and is a major driver of legal action against electric utilities in North America. We investigated factors associated with avian electrocutions so poles that are likely to electrocute a bird can be identified and retrofitted prior to causing avian mortality. We used historical data from southern California to identify patterns of avian electrocution by voltage, month, and year to identify species most often killed by electrocution in our study area and to develop a predictive model that compared poles where an avian electrocution was known to have occurred (electrocution poles) with poles where no known electrocution occurred (comparison poles). We chose variables that could be quantified by personnel with little training in ornithology or electric systems. Electrocutions were more common at distribution voltages (≤ 33 kV) and during breeding seasons and were more commonly reported after a retrofitting program began. Red-tailed Hawks (Buteo jamaicensis) (n = 265) and American Crows (Corvus brachyrhynchos) (n = 258) were the most commonly electrocuted species. In the predictive model, 4 of 14 candidate variables were required to distinguish electrocution poles from comparison poles: number of jumpers (short wires connecting energized equipment), number of primary conductors, presence of grounding, and presence of unforested unpaved areas as the dominant nearby land cover. When tested against a sample of poles not used to build the model, our model distributed poles relatively normally across electrocution-risk values and identified the average risk as higher for electrocution poles relative to comparison poles. Our model can be used to reduce avian electrocutions through proactive identification and targeting of high-risk poles for retrofitting. PMID:24033371

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

    PubMed

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

    2015-10-22

    Avian hepatitis E virus (HEV) is the main causative agent of big liver and spleen disease and hepatitis-splenomegaly syndrome in chickens, and is genetically and antigenically related to mammalian HEVs. HEV capsid protein contains immunodominant epitopes and induces a protective humoral immune response. A better understanding of the antigenic composition of this protein is critically important for the development of effective vaccine and sensitive and specific serological assays. To date, six linear antigenic domains (I-VI) have been characterized in avian HEV capsid protein and analyzed for their applications in the serological diagnosis and vaccine design. Domains I and V induce strong immune response in chickens and are common to avian, human, and swine HEVs, indicating that the shared epitopes hampering differential diagnosis of avian HEV infection. Domains III and IV are not immunodominant and elicit a weak immune response. Domain VI, located in the N-terminal region of the capsid protein, can also trigger an intense immune response, but the anti-domain VI antibodies are transient. The protection analysis showed that the truncated capsid protein containing the C-terminal 268 amino acid residues expressed by the bacterial system can provide protective immunity against avian HEV infection in chickens. However, the synthetic peptides incorporating the different linear antigenic domains (I-VI) and epitopes are non-protective. The antigenic composition of avian HEV capsid protein is altogether complex. To develop an effective vaccine and accurate serological diagnostic methods, more conformational antigenic domains or epitopes are to be characterized in detail. PMID:26340899

  5. Fragmentation methods in laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Jiang, Zhi X.; Whitehurst, Colin; King, Terence A.

    1991-07-01

    Following a series of opto-acoustic-mechanical and spectroscopic studies into the basic mechanisms of laser lithotripsy, a plasma-mediated opto-mechanical energy transfer model is presented. Laser energy, first absorbed by the calculi material at the surface and couples into the initiated plasma following ionization of vaporized material, is finally transformed into destructive mechanical energy via a shock wave induced by the impulsive expansion of the resulting plasma. This leads to the fragmentation of the calculi. The laser-plasma energy coupling gives a new definition for the fluence threshold to laser induced breakdown, which agrees with shock wave detection and analysis. A laser pulse shape with initial low intensity and sufficient fluence to vaporize a required amount of target material (lasting a few microsecond(s) ) and terminating in a short, intense pulse of about 1microsecond(s) or less, to couple most of the laser energy into the dense young plasma and so create high pressures, is required to produce optimum effect for laser lithotripsy. An opto-mechanical coupler has been designed which transfers the maximum laser energy into mechanically destructive energy, and successfully fragments various types of urinary and biliary calculi even including those calculi with poor surface absorptance, like pure white cystine. A solid state laser, Ho:YAG (2.1 micrometers wavelength and 150 microsecond(s) pulse width), has also been tested as an alternative to the flashlamp-excited dye laser. The underwater shock wave induced by this laser has been measured and has successfully fragmented calculi with poor absorptance in the visible region.

  6. Sample preparation for avian and porcine influenza virus cDNA amplification simplified: Boiling vs. conventional RNA extraction.

    PubMed

    Fereidouni, Sasan R; Starick, Elke; Ziller, Mario; Harder, Timm C; Unger, Hermann; Hamilton, Keith; Globig, Anja

    2015-09-01

    RNA extraction and purification is a fundamental step that allows for highly sensitive amplification of specific RNA targets in PCR applications. However, commercial extraction kits that are broadly used because of their robustness and high yield of purified RNA are expensive and labor-intensive. In this study, boiling in distilled water or a commercial lysis buffer of different sample matrices containing avian or porcine influenza viruses was tested as an alternative. Real-time PCR (RTqPCR) for nucleoprotein gene fragment was used as read out. Results were compared with freshly extracted RNA by use of a commercial extraction kit. Different batches of virus containing materials, including diluted virus positive allantoic fluid or cell culture supernatant, and avian faecal, cloacal or oropharyngeal swab samples were used in this study. Simple boiling of samples without any additional purification steps can be used as an alternative RNA preparation method to detect influenza A virus nucleoprotein RNA in oropharyngeal swab samples, allantoic fluid or cell-culture supernatant. The boiling method is not applicable for sample matrices containing faecal material. PMID:25929989

  7. Fission fragment excited laser system

    DOEpatents

    McArthur, David A.; Tollefsrud, Philip B.

    1976-01-01

    A laser system and method for exciting lasing action in a molecular gas lasing medium which includes cooling the lasing medium to a temperature below about 150 K and injecting fission fragments through the lasing medium so as to preferentially excite low lying vibrational levels of the medium and to cause population inversions therein. The cooled gas lasing medium should have a mass areal density of about 5 .times. 10.sup.-.sup.3 grams/square centimeter, relaxation times of greater than 50 microseconds, and a broad range of excitable vibrational levels which are excitable by molecular collisions.

  8. The fragmentation process at HERMES

    SciTech Connect

    Maiheu, B.

    2005-10-06

    In semi-inclusive deep-inelastic scattering one can study the fragmentation process of partons by extracting multiplicity distributions for the resulting hadrons. At the HERMES experiment a unique possibility exists to study this hadronization at a {radical}(s) of 7.2 GeV. Making full use of the hadron identification capabilities of a Ring Imaging Cerenkov (RICH) detector, we were able to extract charge-separated pion and kaon multiplicities. Significant effort was put reducing the model dependence of the result by tuning the used MC generator and using an unfolding method to correct for experimental inefficiencies and migration of events due to both radiative and detector smearing.

  9. Ternary fission of nuclei into comparable fragments

    SciTech Connect

    Karpeshin, F. F.

    2015-07-15

    The problem of nuclear fission into three comparable fragments is considered. A mechanism of true ternary fission is proposed. In contrast to sequential fission, where the three fragments arise upon two sequential events of binary fission, the mechanism in question relies on a scenario that originally involves fission into three fragments. This mechanism is driven by a hexadecapole deformation of the fissioning nucleus, in contrast to binary fission associated with quadrupole vibrations of the nuclear surface. The fragment-mass ratios are estimated. The dynamics of formation of collinear fragments and their subsequent motion in opposite directions is traced. The calculated probability of true ternary fission complies with observed values.

  10. Velocity distribution of fragments of catastrophic impacts

    NASA Technical Reports Server (NTRS)

    Takagi, Yasuhiko; Kato, Manabu; Mizutani, Hitoshi

    1992-01-01

    Three dimensional velocities of fragments produced by laboratory impact experiments were measured for basalts and pyrophyllites. The velocity distribution of fragments obtained shows that the velocity range of the major fragments is rather narrow, at most within a factor of 3 and that no clear dependence of velocity on the fragment mass is observed. The NonDimensional Impact Stress (NDIS) defined by Mizutani et al. (1990) is found to be an appropriate scaling parameter to describe the overall fragment velocity as well as the antipodal velocity.

  11. Coagulation and fragmentation with discrete mass loss

    NASA Astrophysics Data System (ADS)

    Blair, Pamela N.; Lamb, Wilson; Stewart, Iain W.

    2007-05-01

    A nonlinear integro-differential equation that models a coagulation and multiple fragmentation process in which discrete fragmentation mass loss can occur is examined using the theory of strongly continuous semigroups of operators. Under the assumptions that the coagulation kernel is bounded and the fragmentation rate function a satisfies a linear growth condition, global existence and uniqueness of solutions that lose mass in accordance with the model are established. In the case when no coagulation is present and the fragmentation process is governed by power-law kernels, an explicit formula is given for the substochastic semigroup associated with the resulting mass-loss fragmentation equation.

  12. Sequence conservation of an avian centromeric repeated DNA component.

    PubMed

    Madsen, C S; Brooks, J E; de Kloet, E; de Kloet, S R

    1994-06-01

    The approximately 190-bp centromeric repeat monomers of the spur-winged lapwing (Vanellus spinosus, Charadriidae), the Chilean flamingo (Phoenicopterus chilensis, Phoenicopteridae), the sarus crane (Grus antigone, Gruidae), parrots (Psittacidae), waterfowl (Anatidae), and the merlin (Falco columbarius, Falconidae) contain elements that are interspecifically highly variable, as well as elements (trinucleotides and higher order oligonucleotides) that are highly conserved in sequence and relative location within the repeat. Such conservation suggests that the centromeric repeats of these avian species have evolved from a common ancestral sequence that may date from very early stages of avian radiation. PMID:8034177

  13. Avian cholera in Southern Great Petrel (Macronectes giganteus) from Antarctica

    USGS Publications Warehouse

    Leotta, G.A.; Rivas, M.; Chinen, I.; Vigo, G.B.; Moredo, F.A.; Coria, N.; Wolcott, M.J.

    2003-01-01

    A southern giant petrel (Macronectes giganteus) was found dead at Potter Peninsula, King George Island, South Shetland, Antarctica. The adult male was discovered approximately 48 hr after death. Macroscopic and microscopic lesions were compatible with avian cholera and the bacterium Pasteurella multocida subsp. gallicida, serotype A1 was isolated from lung, heart, liver, pericardial sac, and air sacs. In addition, Escherichia coli was isolated from pericardial sac and air sacs. This is the first known report of avian cholera in a southern giant petrel in Antarctica.

  14. Sensitivity and entanglement in the avian chemical compass.

    PubMed

    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. PMID:25375523

  15. Sensitivity and entanglement in the avian chemical compass

    NASA Astrophysics Data System (ADS)

    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.

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

    USGS Publications Warehouse

    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.

  17. Novel Receptor Specificity of Avian Gammacoronaviruses That Cause Enteritis

    PubMed Central

    Ambepitiya Wickramasinghe, I. N.; de Vries, R. P.; Weerts, E. A. W. S.; van Beurden, S. J.; Peng, W.; McBride, R.; Ducatez, M.; Guy, J.; Brown, P.; Eterradossi, N.; Gröne, A.; Paulson, J. C.

    2015-01-01

    ABSTRACT Viruses exploit molecules on the target membrane as receptors for attachment and entry into host cells. Thus, receptor expression patterns can define viral tissue tropism and might to some extent predict the susceptibility of a host to a particular virus. Previously, others and we have shown that respiratory pathogens of the genus Gammacoronavirus, including chicken infectious bronchitis virus (IBV), require specific α2,3-linked sialylated glycans for attachment and entry. Here, we studied determinants of binding of enterotropic avian gammacoronaviruses, including turkey coronavirus (TCoV), guineafowl coronavirus (GfCoV), and quail coronavirus (QCoV), which are evolutionarily distant from respiratory avian coronaviruses based on the viral attachment protein spike (S1). We profiled the binding of recombinantly expressed S1 proteins of TCoV, GfCoV, and QCoV to tissues of their respective hosts. Protein histochemistry showed that the tissue binding specificity of S1 proteins of turkey, quail, and guineafowl CoVs was limited to intestinal tissues of each particular host, in accordance with the reported pathogenicity of these viruses in vivo. Glycan array analyses revealed that, in contrast to the S1 protein of IBV, S1 proteins of enteric gammacoronaviruses recognize a unique set of nonsialylated type 2 poly-N-acetyl-lactosamines. Lectin histochemistry as well as tissue binding patterns of TCoV S1 further indicated that these complex N-glycans are prominently expressed on the intestinal tract of various avian species. In conclusion, our data demonstrate not only that enteric gammacoronaviruses recognize a novel glycan receptor but also that enterotropism may be correlated with the high specificity of spike proteins for such glycans expressed in the intestines of the avian host. IMPORTANCE Avian coronaviruses are economically important viruses for the poultry industry. While infectious bronchitis virus (IBV), a respiratory pathogen of chickens, is rather well

  18. Heavy Ion Fragmentation Experiments at the Bevatron

    NASA Technical Reports Server (NTRS)

    Heckman, H. H.

    1975-01-01

    Fragmentation processes of heavy nuclei in matter using the heavy-ion capability of the Bevatron were studied. The purpose was to obtain the single particle inclusive spectra of secondary nuclei produced at 0 deg by the fragmentation of heavy ion beam projectiles. The process being examined is B+T yields F + anything, where B is the beam nucleus, T is the target nucleus, and F is the detected fragment. The fragments F are isotopically identified by experimental procedures involving magnetic analysis, energy loss and time-of-flight measurements. Attempts were also made to: (1) measure the total and partial production cross section for all isotopes, (2) test the applicability of high-energy multi-particle interaction theory to nuclear fragmentation, (3) apply the cross-section data and fragmentation probabilities to cosmic ray transport theory, and (4) search for systematic behavior of fragment production as a means to improve existing semi-empirical theories of cross sections.

  19. Avian influenza in Chile: a successful experience.

    PubMed

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

    2007-03-01

    Avian influenza (AI) was diagnosed in May 2002 for the first time in Chile and South America. The epidemic was caused by the highly pathogenic AI (HPAI) virus subtype H7N3 that emerged from a low pathogenic virus. The index farm was a broiler breeder, located in San Antonio, V Region, which at the time was a densely populated poultry area. Stamping of 465,000 breeders, in 27 sheds, was immediately conducted. Surveillance activities detected a second outbreak, 1 wk later, at a turkey breeding farm from the same company. The second farm was located 4 km from the index case. Only 25% of the sheds were infected, and 18,500 turkeys were destroyed. In both outbreaks, surveillance zones and across-country control measures were established: prediagnosis quarantine, depopulation, intensive surveillance, movement control, and increased biosecurity. Other measures included cleaning, disinfection, and controlling the farms with sentinels to detect the potential presence of the virus. Zoning procedures were implemented to allow the international trade of poultry products from unaffected areas. Positive serologic results to H5N2 virus also were detected in other poultry farms, but there was no evidence of clinical signs or virus isolation. Epidemiological investigation and laboratory confirmation determined that positive serology was related to a contaminated imported batch of vaccine against inclusion body hepatitis. All actions taken allowed the control of the epidemic, and within 7 mo, Chile was free of AI. Epidemic and control measures that prevented further spread are described in this article, which illustrates the importance of a combination of control measures during and after an outbreak of AI. This study is a good example of how veterinary services need to respond if their country is affected by HPAI. PMID:17494584

  20. Role of estrogen in avian osteoporosis.

    PubMed

    Beck, M M; Hansen, K K

    2004-02-01

    One of the difficulties associated with commercial layer production is the development of osteoporosis in hens late in the production cycle. In light of this fact and because of hens' unique requirements for Ca, many studies have focused on the regulation of Ca and the role of estrogen in this process. The time course of estrogen synthesis over the productive life of hens has been well documented; increased circulating estrogen accompanies the onset of sexual maturity while decreases signal a decline in egg production prior to a molt. Numbers of estrogen receptors decrease with age in numerous tissues. The parallel changes in calcium-regulating proteins, primarily Calbindin D28K, and in the ability of duodenal cells to transport Ca, are thought to occur as a result of the changes in estrogen, and are also reversible by the molt process. In addition to the traditional model of estrogen action, evidence now exists for a possible nongenomic action of estrogen via membrane-bound receptors, demonstrated by extremely rapid surges of ionized Ca in chicken granulosa cells in response to 17beta-estradiol. Estrogen receptors have also been discovered in duodenal tissue, and tamoxifen, which binds to the estrogen receptor, has been shown to cause a rapid increase in Ca transport in the duodenum. In addition, recent evidence also suggests that mineralization of bone per se may not explain entirely the etiology of osteoporosis in the hen but that changes in the collagen matrix may contribute through decreases in bone elasticity. Taken together, these studies suggest that changes in estrogen synthesis and estrogen receptor populations may underlie the age-related changes in avian bone. As with postmenopausal women, dietary Ca and vitamin D are of limited benefit as remedies for osteoporosis in the hen. PMID:14979570

  1. Avian influenza: Myth or mass murder?

    PubMed Central

    Louie, Carol

    2005-01-01

    The purpose of the present article was to determine whether avian influenza (AI) is capable of causing a pandemic. Using research from a variety of medical journals, books and texts, the present paper evaluates the probability of the AI virus becoming sufficiently virulent to pose a global threat. Previous influenza A pandemics from the past century are reviewed, focusing on the mortality rate and the qualities of the virus that distinguish it from other viruses. Each of the influenza A 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. PMID:18159544

  2. Habitat fragmentation reduces nest survival in an Afrotropical bird community in a biodiversity hotspot

    USGS Publications Warehouse

    Newmark, W.D.; Stanley, T.R.

    2011-01-01

    Ecologists have long hypothesized that fragmentation of tropical landscapes reduces avian nest success. However, this hypothesis has not been rigorously assessed because of the difficulty of finding large numbers of well-hidden nests in tropical forests. Here we report that in the East Usambara Mountains in Tanzania, which are part of the Eastern Arc Mountains, a global biodiversity hotspot, that daily nest survival rate and nest success for seven of eight common understory bird species that we examined over a single breeding season were significantly lower in fragmented than in continuous forest, with the odds of nest failure for these seven species ranging from 1.9 to 196.8 times higher in fragmented than continuous forest. Cup-shaped nests were particularly vulnerable in fragments. We then examined over six breeding seasons and 14 study sites in a multivariable survival analysis the influence of landscape structure and nest location on daily nest survival for 13 common species representing 1,272 nests and four nest types (plate, cup, dome, and pouch). Across species and nest types, area, distance of nest to edge, and nest height had a dominant influence on daily nest survival, with area being positively related to nest survival and distance of nest to edge and nest height being both positively and negatively associated with daily nest survival. Our results indicate that multiple environmental factors contribute to reduce nest survival within a tropical understory bird community in a fragmented landscape and that maintaining large continuous forest is important for enhancing nest survival for Afrotropical understory birds.

  3. Nonlinear inflaton fragmentation after preheating

    SciTech Connect

    Felder, Gary N.; Kofman, Lev

    2007-02-15

    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 nongaussian and the field dynamics become chaotic and irreversible. Visualization of the field dynamics in position space reveals that nonlinear interactions generate nongaussian 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 growing and begin to expand. The subsequent dynamics is determined by expansion and superposition of the scalar waves originating from the peaks. Multiple wave superposition results in phase mixing and turbulent wave dynamics. Thus, the short intermediate stage is defined by the formation, expansion and collision of bubblelike field inhomogeneities associated with the peaks of the original gaussian field. This process is qualitatively similar to the bubblelike inflaton fragmentation that occurs during tachyonic preheating after hybrid or new inflation.

  4. Fragmentation in filamentary molecular clouds

    NASA Astrophysics Data System (ADS)

    Contreras, Yanett; Garay, Guido; Rathborne, Jill M.; Sanhueza, Patricio

    2016-02-01

    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 overdensities 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 overdensities (clumps). In this paper, we present a multiwavelength 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 that most clumps have sufficient mass and density to form high-mass stars, supporting the idea that high-mass stars and clusters form within filaments.

  5. Structures of endothiapepsin-fragment complexes from crystallographic fragment screening using a novel, diverse and affordable 96-compound fragment library.

    PubMed

    Huschmann, Franziska U; Linnik, Janina; Sparta, Karine; Ühlein, Monika; Wang, Xiaojie; Metz, Alexander; Schiebel, Johannes; Heine, Andreas; Klebe, Gerhard; Weiss, Manfred S; Mueller, Uwe

    2016-05-01

    Crystallographic screening of the binding of small organic compounds (termed fragments) to proteins is increasingly important for medicinal chemistry-oriented drug discovery. To enable such experiments in a widespread manner, an affordable 96-compound library has been assembled for fragment screening in both academia and industry. The library is selected from already existing protein-ligand structures and is characterized by a broad ligand diversity, including buffer ingredients, carbohydrates, nucleotides, amino acids, peptide-like fragments and various drug-like organic compounds. When applied to the model protease endothiapepsin in a crystallographic screening experiment, a hit rate of nearly 10% was obtained. In comparison to other fragment libraries and considering that no pre-screening was performed, this hit rate is remarkably high. This demonstrates the general suitability of the selected compounds for an initial fragment-screening campaign. The library composition, experimental considerations and time requirements for a complete crystallographic fragment-screening campaign are discussed as well as the nine fully refined obtained endothiapepsin-fragment structures. While most of the fragments bind close to the catalytic centre of endothiapepsin in poses that have been observed previously, two fragments address new sites on the protein surface. ITC measurements show that the fragments bind to endothiapepsin with millimolar affinity. PMID:27139825

  6. Reanalysis of Wupus agilis (Early Cretaceous) of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks.

    PubMed

    Xing, Lida; Buckley, Lisa G; McCrea, Richard T; Lockley, Martin G; Zhang, Jianping; Piñuela, Laura; Klein, Hendrik; Wang, Fengping

    2015-01-01

    Trace fossils provide the only records of Early Cretaceous birds from many parts of the world. The identification of traces from large avian track-makers is made difficult given their overall similarity in size and tridactyly in comparison with traces of small non-avian theropods. Reanalysis of Wupus agilis from the Early Cretaceous (Aptian-Albian) Jiaguan Formation, one of a small but growing number of known avian-pterosaur track assemblages, of southeast China determines that these are the traces of a large avian track-maker, analogous to extant herons. Wupus, originally identified as the trace of a small non-avian theropod track-maker, is therefore similar in both footprint and trackway characteristics to the Early Cretaceous (Albian) large avian trace Limiavipes curriei from western Canada, and Wupus is reassigned to the ichnofamily Limiavipedidae. The reanalysis of Wupus reveals that it and Limiavipes are distinct from similar traces of small to medium-sized non-avian theropods (Irenichnites, Columbosauripus, Magnoavipes) based on their relatively large footprint length to pace length ratio and higher mean footprint splay, and that Wupus shares enough characters with Limiavipes to be reassigned to the ichnofamily Limiavipedidae. The ability to discern traces of large avians from those of small non-avian theropods provides more data on the diversity of Early Cretaceous birds. This analysis reveals that, despite the current lack of body fossils, large wading birds were globally distributed in both Laurasia and Gondwana during the Early Cretaceous. PMID:25993285

  7. Reanalysis of Wupus agilis (Early Cretaceous) of Chongqing, China as a Large Avian Trace: Differentiating between Large Bird and Small Non-Avian Theropod Tracks

    PubMed Central

    Xing, Lida; Buckley, Lisa G.; McCrea, Richard T.; Lockley, Martin G.; Zhang, Jianping; Piñuela, Laura; Klein, Hendrik; Wang, Fengping

    2015-01-01

    Trace fossils provide the only records of Early Cretaceous birds from many parts of the world. The identification of traces from large avian track-makers is made difficult given their overall similarity in size and tridactyly in comparison with traces of small non-avian theropods. Reanalysis of Wupus agilis from the Early Cretaceous (Aptian-Albian) Jiaguan Formation, one of a small but growing number of known avian-pterosaur track assemblages, of southeast China determines that these are the traces of a large avian track-maker, analogous to extant herons. Wupus, originally identified as the trace of a small non-avian theropod track-maker, is therefore similar in both footprint and trackway characteristics to the Early Cretaceous (Albian) large avian trace Limiavipes curriei from western Canada, and Wupus is reassigned to the ichnofamily Limiavipedidae. The reanalysis of Wupus reveals that it and Limiavipes are distinct from similar traces of small to medium-sized non-avian theropods (Irenichnites, Columbosauripus, Magnoavipes) based on their relatively large footprint length to pace length ratio and higher mean footprint splay, and that Wupus shares enough characters with Limiavipes to be reassigned to the ichnofamily Limiavipedidae. The ability to discern traces of large avians from those of small non-avian theropods provides more data on the diversity of Early Cretaceous birds. This analysis reveals that, despite the current lack of body fossils, large wading birds were globally distributed in both Laurasia and Gondwana during the Early Cretaceous. PMID:25993285

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

    PubMed

    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. PMID:25740321

  9. Permeable Gas Flow Influences Magma Fragmentation Speed.

    NASA Astrophysics Data System (ADS)

    Richard, D.; Scheu, B.; Spieler, O.; Dingwell, D.

    2008-12-01

    Highly viscous magmas undergo fragmentation in order to produce the pyroclastic deposits that we observe, but the mechanisms involved remain unclear. The overpressure required to initiate fragmentation depends on a number of physical parameters, such as the magma's vesicularity, permeability, tensile strength and textural properties. It is clear that these same parameters control also the speed at which a fragmentation front travels through magma when fragmentation occurs. Recent mathematical models of fragmentation processes consider most of these factors, but permeable gas flow has not yet been included in these models. However, it has been shown that permeable gas flow through a porous rock during a sudden decompression event increases the fragmentation threshold. Fragmentation experiments on natural samples from Bezymianny (Russia), Colima (Mexico), Krakatau (Indonesia) and Augustine (USA) volcanoes confirm these results and suggest in addition that high permeable flow rates may increase the speed of fragmentation. Permeability from the investigated samples ranges from as low as 5 x 10-14 to higher than 9 x 10- 12 m2 and open porosity ranges from 16 % to 48 %. Experiments were performed for each sample series at applied pressures up to 35 MPa. Our results indicate that the rate of increase of fragmentation speed is higher when the permeability is above 10-12 m2. We confirm that it is necessary to include the influence of permeable flow on fragmentation dynamics.

  10. Knowledge-based fragment binding prediction.

    PubMed

    Tang, Grace W; Altman, Russ B

    2014-04-01

    Target-based drug discovery must assess many drug-like compounds for potential activity. Focusing on low-molecular-weight compounds (fragments) can dramatically reduce the chemical search space. However, approaches for determining protein-fragment interactions have limitations. Experimental assays are time-consuming, expensive, and not always applicable. At the same time, computational approaches using physics-based methods have limited accuracy. With increasing high-resolution structural data for protein-ligand complexes, there is now an opportunity for data-driven approaches to fragment binding prediction. We present FragFEATURE, a machine learning approach to predict small molecule fragments preferred by a target protein structure. We first create a knowledge base of protein structural environments annotated with the small molecule substructures they bind. These substructures have low-molecular weight and serve as a proxy for fragments. FragFEATURE then compares the structural environments within a target protein to those in the knowledge base to retrieve statistically preferred fragments. It merges information across diverse ligands with shared substructures to generate predictions. Our results demonstrate FragFEATURE's ability to rediscover fragments corresponding to the ligand bound with 74% precision and 82% recall on average. For many protein targets, it identifies high scoring fragments that are substructures of known inhibitors. FragFEATURE thus predicts fragments that can serve as inputs to fragment-based drug design or serve as refinement criteria for creating target-specific compound libraries for experimental or computational screening. PMID:24762971

  11. Magma fragmentation speed: an experimental determination

    NASA Astrophysics Data System (ADS)

    Spieler, O.; Dingwell, D. B.; Alidibirov, M.

    2004-01-01

    The propagation speed of a fragmentation front, combined with the ascent velocity of magma is, in all likelihood, a controlling factor in the dynamics of explosive volcanic eruptions. Direct measurement of the 'fragmentation speed' in natural systems appears to be impossible at present. Fortunately, laboratory experiments can provide information on the propagation speed of the fragmentation front. Here we present the results of fragmentation speed determinations using a so-called 'fragmentation bomb'. These are, to the best of our knowledge, the first in situ fragmentation speed determinations performed on magma. Natural magma samples (Merapi basaltic andesite, Mount St. Helens dacite and Unzen dacite) have been investigated in the temperature range of 20-950°C and at pressures up to 25 MPa. Two techniques have been employed. Firstly, in experiments at 20°C, dynamic pressure transducers were placed above and below the magma samples and the fragmentation speed of the magma sample was derived from an analysis of the decompression curves. Secondly, at elevated temperatures, an alternative technique was introduced and successfully employed. This involved the severing via fragmentation of conducting wires placed within the samples at various heights. Fragmentation speeds are very low, falling in the range of 2-70 m/s and increasing with an increase in the magnitude of the decompression step responsible for the fragmentation. The first high-temperature determination seems consistent with low-temperature results. Implications for explosive volcanism are discussed briefly.

  12. Digital diffraction detection of protein markers for avian influenza.

    PubMed

    Im, Hyungsoon; Park, Yong Il; Pathania, Divya; Castro, Cesar M; Weissleder, Ralph; Lee, Hakho

    2016-04-12

    Rapid pathogen testing is expected to play a critical role in infection control and in limiting epidemics. Smartphones equipped with state-of-the-art computing and imaging technologies have emerged as new point-of-use (POU) sensing platforms. We herein report a new assay format for fast, sensitive and portable detection of avian influenza-associated antibodies. PMID:26980325

  13. Avian Encephalomyelitis in Layer Pullets Associated with Vaccination.

    PubMed

    Sentíes-Cué, C Gabriel; Gallardo, Rodrigo A; Reimers, Nancy; Bickford, Arthur A; Charlton, Bruce R; Shivaprasad, H L

    2016-06-01

    Avian encephalomyelitis (AE) was diagnosed in three flocks of leghorn layer pullets following AE vaccination. Ages of the birds were 11, 12, and 14 wk. The submissions came from three different companies located in two geographic areas of the Central Valley of California. The clinical signs included birds down on their legs, unilateral recumbency or sitting on their hocks, lethargy, reluctance to move, dehydration, unevenness in size, low weight, tremors of the head in a few birds, and mildly to moderately elevated mortality. The flocks had been vaccinated against fowl pox and AE with a combined product in the wing-web 2 wk prior to the onset of AE clinical signs. Histopathologic examination revealed lesions consistent with AE, including lymphocytic perivascular infiltration and neuronal central chromatolysis in the brain and spinal cord, as well as gliosis in the cerebellar molecular layer. The AE virus was detected by reverse-transcriptase PCR in the brain homogenate from three cases and peripheral nerves in one case. Additionally, the AE virus was isolated in specific-pathogen-free (SPF) embryonated eggs from brain tissue pool samples. Other avian viral infections capable of causing encephalitis, including avian paramyxoviruses, avian influenza virus (AIV), West Nile virus (WNV), eastern equine encephalitis virus (EEEV), and western equine encephalitis virus (WEEV), were ruled out by attempting virus isolation and molecular procedures. PMID:27309297

  14. Impact of host genes on resistance to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    H5N1 high pathogenicity avian influenza (HPAI) virus has caused massive outbreaks of infection and disease in poultry, significant numbers of infections in wild aquatic birds and some infections in mammals and humans in Asia, Europe and Africa. The primary intervention strategy in poultry within de...

  15. Pathobiology of avian influenza virus infections in wild birds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Individual avian Influenza (AI) viruses vary in their ability to produce infection, disease and death in different bird species. Based on the pathobiological features in chickens, AI viruses (AIV) are categorized as low pathogenicity (LPAI) or high pathogenicity (HPAI) viruses, and can be of any of...

  16. Rumor Surveillance and Avian Influenza H5N1

    PubMed Central

    Patel, Mahomed; Olowokure, Babatunde; Roces, Maria C.; Oshitani, Hitoshi

    2005-01-01

    We describe the enhanced rumor surveillance during the avian influenza H5N1 outbreak in 2004. The World Health Organization’s Western Pacific Regional Office identified 40 rumors; 9 were verified to be true. Rumor surveillance informed immediate public health action and prevented unnecessary and costly responses. PMID:15757567

  17. The changing ecology, epidemiology and pathobiology of avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-five epizootics of high pathogenicity avian influenza (HPAI) have occurred in the world since 1959. The largest of these outbreaks has been the H5N1 HPAI which has caused problems in poultry and some wild birds in over 60 countries of Asia, Europe and Africa since beginning in 1996. The H5N1 ...

  18. Avian influenza: worldwide situation and effectiveness of current vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 63 countries during the past 18 years. The majority of the recent outbreaks of H5N2 HPAI have occurred in Indonesia, Egypt, Vietnam, and Bangladesh, in decreasi...

  19. Opportunistic Pulmonary Bordetella hinzii Infection after Avian Exposure

    PubMed Central

    Dupin, Clarisse; Bénézit, François; Goret, Julien; Piau, Caroline; Jouneau, Stéphane; Guillot, Sophie; Mégraud, Francis; Kayal, Samer; Desrues, Benoit; Le Coustumier, Alain; Guiso, Nicole

    2015-01-01

    We report 2 cases of pulmonary Bordetella hinzii infection in immunodeficient patients. One of these rare cases demonstrated the potential transmission of the bacteria from an avian reservoir through occupational exposure and its persistence in humans. We establish bacteriologic management of these infections and suggest therapeutic options if needed. PMID:26584467

  20. Prevention and control of avian influenza in Asia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 62 countries during the past 15 years. For 2011-2012, 19 countries reported outbreaks of H5N1 in domestic poultry, wild birds or both. The majority of the outbr...

  1. Immunohistochemical staining of avian influenza viruses in tissues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunohistochemical methods are commonly used for studying the pathogenesis of avian influenza virus by allowing the identification of sites of replication of the virus in infected tissues and the correlation with the histopathological changes observed. In this chapter, the materials and methods fo...

  2. 9 CFR 113.326 - Avian Pox Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  3. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., 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....

  4. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., 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....

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

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., 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....

  6. 9 CFR 113.326 - Avian Pox Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  7. 9 CFR 113.326 - Avian Pox Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  8. 9 CFR 113.326 - Avian Pox Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  9. 9 CFR 113.326 - Avian Pox Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.326 Avian Pox Vaccine. Fowl Pox Vaccine and Pigeon Pox Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  10. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., 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....

  11. 9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    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....

  12. Designing and Presenting Avian Research to Facilitate Integration with Management

    SciTech Connect

    Moorman, C.E.

    2000-10-01

    The paper identifies communication gaps between managers and avian researchers. It is proposed to include managers in the design of studies. The distinction between applied and basic research is diminishing. Researchers should emphasize scale when viewing the results of their research. An example is provided through illustration of work at SRS.

  13. DETECTION OF AVIAN INFLUENZA VIRUS USING AN INTERFEROMETRIC BIOSENSOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An optical interferometric waveguide immunoassay for direct and label-less detection of avian influenza virus is described. The assay response is based on index of refraction changes that occur upon binding of virus particles to antigen (hemagglutinin) specific antibodies on the waveguide surface. ...

  14. Practical aspects of surveillance for avian influenza in poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The overall approach to surveillance for avian influenza virus (AIV) in poultry will vary depending on the situation, resources, and goals of a given surveillance program. However, the optimal methods for sample collection, transport, and handling are universal. Many practical questions have been ...

  15. Review of rapid molecular diagnostic tools for avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular diagnostics tests are commonly used to diagnose avian influenza virus (AIV) because they are sensitive, can be performed rapidly, with high throughput, and at a moderate cost. Molecular diagnostic tests have recently proven themselves to be invaluable in controlling disease outbreaks arou...

  16. Recent worldwide outbreaks of avian influenza and methods for control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-five epizootics of high pathogenicity avian influenza (HPAI) have occurred in the world since 1959. The largest of these outbreaks has been the H5N1 HPAI which has caused problems in poultry and other birds in 55 countries of Asia, Europe and Africa since 1996. These viruses have also cause...

  17. Rapidly Expanding Range of Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    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. PMID:26079209

  18. Highly pathogenic avian influenza virus among wild birds in Mongolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The central Asian country of Mongolia supports large populations of migratory water birds that migrate across much of Asia where highly pathogenic avian influenza (HPAI) virus subtype H5N1 is endemic. This, together with the near absence of domestic poultry, makes Mongolia an ideal location to unde...

  19. Thermal inactivation of avian influenza virus in liquid egg products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty eight percent of the 200 million cases of shelled eggs produced per year in the U.S. are processed as liquid egg product. The U.S. also exports internationally a large amount of egg products. Although the U.S. is normally free of avian influenza, concern about contamination of egg product wit...

  20. Avian Influenza Vaccine Technologies and Laboratory Methods for Assessing Protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines can be used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein and such protection is HA subtype specific. A variety of vaccines have been ...

  1. Avian influenza: Public health and food safety concerns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) is an asymptomatic infection or disease caused by Influenza virus A. AI viruses are species specific and rarely crosses the species barrier. However subtypes H5, H7 and H9 have caused sporadic infections in humans mostly as a result of direct contact with infected birds. H5N1 hi...

  2. Avian Bornavirus in Free-Ranging Psittacine Birds, Brazil

    PubMed Central

    Encinas-Nagel, Nuri; Enderlein, Dirk; Piepenbring, Anne; Herden, Christiane; Heffels-Redmann, Ursula; Felippe, Paulo A.N.; Arns, Clarice; Hafez, Hafez M.

    2014-01-01

    Avian bornavirus (ABV) has been identified as the cause of proventricular dilatation disease in birds, but the virus is also found in healthy birds. Most studies of ABV have focused on captive birds. We investigated 86 free-ranging psittacine birds in Brazil and found evidence for natural, long-term ABV infection. PMID:25417715

  3. Highly Pathogenic Avian Influenza: Intersecting Humans, Animals, and the Environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Eurasian-African H5N1 highly pathogenic avian influenza (HPAI) virus has caused an unprecedented epizootic affecting mainly poultry, but has crossed multiple species barriers to infect captive and wild birds, carnivorous mammals and humans. There is still great concern over the continued infecti...

  4. 9 CFR 113.31 - Detection of avian lymphoid leukosis.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Detection of avian lymphoid leukosis. 113.31 Section 113.31 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Standard Procedures §...

  5. 9 CFR 113.31 - Detection of avian lymphoid leukosis.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Detection of avian lymphoid leukosis. 113.31 Section 113.31 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Standard Procedures §...

  6. Movements of birds and avian influenza from Asia into Alaska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Asian-origin avian influenza (AI) virus is spread in part by migratory birds. We describe the extensive overlap of Asian and American bird vectors in Alaska as the ‘Beringian Crucible’. Seven years of AI surveillance among waterfowl and shorebirds in this region (1998-2004; 8,255 samples) show remar...

  7. SIMPLIFIED METHOD FOR EXTRACTING BOUND PESTICIDES FROM AVIAN SERUM

    EPA Science Inventory

    A simple solid-phase extraction (SPE) method was developed to extract organochlorine pesticides (OCs) and persistent organic pollutants (POPs) from avian serum. In this method, a 1-mL serum sample fortified with two levels of OCs or POPs was treated with 8M urea or 4M urea and 4...

  8. Newcastle disease virus detection and differentiation from avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Newcastle disease (ND) is a contagious and often fatal disease that affects over 250 bird species worldwide, and is caused by infection with virulent strains of avian paramyxovirus-1 (APMV-1) of the family Paramyxoviridae, genus Avulavirus. Infections of poultry with virulent strains of APMV-1 (New...

  9. Avian Influenza vaccine technologies and laboratory methods for assessing protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines can be used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein and such protection is HA subtype specific. A variety of vaccines have been ...

  10. Experimental vaccinations for avian influenza virus including DIVA approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We continue to improve our understanding of avian immunology and are gaining new technological tools that can be used for the immunization of domestic animals. With all these advances we still have to balance the protection that we receive from treatment (i.e vaccination) versus the cost to adminis...

  11. EFFECT OF ADULT MALLARD AGE ON AVIAN REPRODUCTIVE TESTS

    EPA Science Inventory

    The study was designed to determine the effect of using two different ages of mallard (Anas platyrhynchos) adults within the first breeding season on reproductive tests under standard Toxic Substances Control Act avian reproductive guidelines. The adult age groups were 7 and 11 m...

  12. Avian Influenza Vaccination of Poultry and Passive Case Reporting, Egypt

    PubMed Central

    Grosbois, Vladimir; Jobre, Yilma; Saad, Ahmed; El Nabi, Amira Abd; Galal, Shereen; Kalifa, Mohamed; El Kader, Soheir Abd; Dauphin, Gwenaëlle; Roger, François; Lubroth, Juan; Peyre, Marisa

    2012-01-01

    We investigated the influence of a mass poultry vaccination campaign on passive surveillance of highly pathogenic avian influenza subtype (H5N1) outbreaks among poultry in Egypt. Passive reporting dropped during the campaign, although probability of infection remained unchanged. Future poultry vaccination campaigns should consider this negative impact on reporting for adapting surveillance strategies. PMID:23171740

  13. Canada geese and the epidemiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canada geese (Branta canadensis) are numerous, highly visible, and widely distributed in both migratory and resident populations in North America; as a member of the Order Anseriformes, they are often suggested as a potential reservoir and source for avian influenza (AI) viruses. To further examine...

  14. Immunohistochemical staining of avian influenza virus in tissues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunohistochemical methods are commonly used for studying the pathogenesis of avian influenza (AI) virus by allowing the identification of sites of replication of the virus in infected tissues and the correlation with the histopathological changes observed. In this chapter, the materials and metho...

  15. The changing role of avian influenza on global health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) viruses are a diverse group divided into 144 different subtypes based on different combinations of the 16 hemagglutinin and 9 neuraminidase subtypes, and two different pathotypes (low [LP] and high pathogenicity [HP]). LPAI viruses are maintained in wild birds, and must be adapt...

  16. Rapidly expanding range of highly pathogenic avian influenza viruses

    USGS Publications Warehouse

    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.

  17. Avian influenza worldwide: current status and successful control tools

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 62 countries during the past 15 years. For 2010-2011, 20 countries reported outbreaks of H5N1 in domestic poultry (n = 11), wild birds (n = 4) or both (n=5). Th...

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

    PubMed

    Ear, Sophal

    2011-01-01

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

  19. Diversification and host switching in avian malaria parasites.

    PubMed Central

    Ricklefs, Robert E; Fallon, Sylvia M

    2002-01-01

    The switching of parasitic organisms to novel hosts, in which they may cause the emergence of new diseases, is of great concern to human health and the management of wild and domesticated populations of animals. We used a phylogenetic approach to develop a better statistical assessment of host switching in a large sample of vector-borne malaria parasites of birds (Plasmodium and Haemoproteus) over their history of parasite-host relations. Even with sparse sampling, the number of parasite lineages was almost equal to the number of avian hosts. We found that strongly supported sister lineages of parasites, averaging 1.2% sequence divergence, exhibited highly significant host and geographical fidelity. Event-based matching of host and parasite phylogenetic trees revealed significant cospeciation. However, the accumulated effects of host switching and long distance dispersal cause these signals to disappear before 4% sequence divergence is achieved. Mitochondrial DNA nucleotide substitution appears to occur about three times faster in hosts than in parasites, contrary to findings on other parasite-host systems. Using this mutual calibration, the phylogenies of the parasites and their hosts appear to be similar in age, suggesting that avian malaria parasites diversified along with their modern avian hosts. Although host switching has been a prominent feature over the evolutionary history of avian malaria parasites, it is infrequent and unpredictable on time scales germane to public health and wildlife management. PMID:12028770

  20. Characterization of monoclonal antibodies produced against Avian metapneumovirus Sybtype C

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monoclonal antibodies (MAbs) were prepared against avian metapneumovirus (aMPV) subtype C (aMPV/Minnesota/turkey/1a/97). Six MAbs were selected based on ELISA activities and characterized by isotyping, neutralization test, Western blot analysis, and immunohistochemistry (IHC) assay. The results show...

  1. Rapidly expanding range of highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. Conducting influenza virus pathogenesis studies in avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian infection studies with influenza A are an important means of assessing host susceptibility, viral pathogenesis, host responses to infection, mechanisms of transmission and viral pathotype. Complex systems and natural settings may also be explored with carefully designed infection studies. In ...

  3. 9 CFR 113.31 - Detection of avian lymphoid leukosis.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of avian lymphoid leukosis. 113.31 Section 113.31 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Standard Procedures §...

  4. 9 CFR 113.70 - Pasteurella Multocida Vaccine, Avian Isolate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pasteurella Multocida Vaccine, Avian Isolate. 113.70 Section 113.70 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Bacterial Vaccines §...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

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

    PubMed

    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. PMID:26751596

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. Innate resistance to avian influenza: Of MHC's and Mx proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is an economically important virus of poultry that has significant impact on global trade. Recently, increased attention to animal genomics has been applied to enhance innate resistance to infectious diseases in poultry. Two known contributors to innate resistance are the host m...

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

    PubMed

    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. PMID:18618061

  10. Avian influenza virus infection dynamics in shorebird hosts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using serial cross-sectional data from 2000-2008 and generalized linear models, we examined temporal trends of springtime avian influenza virus (AIV) prevalence and antibody prevalence in four Charadriiformes species at the Delaware Bay migratory stopover site. Prevalence of AIV in Ruddy Turnstones ...

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

    PubMed Central

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

    2011-01-01

    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. PMID:21711191

  12. Multiplex polymerase chain reaction for the detection and differentiation of avian influenza viruses and other poultry respiratory pathogens.

    PubMed

    Rashid, S; Naeem, K; Ahmed, Z; Saddique, N; Abbas, M A; Malik, S A

    2009-12-01

    A multiplex reverse transcription-PCR (mRT-PCR) was developed and standardized for the detection of type A influenza viruses, avian influenza virus (AIV) subtype H7, H9, and H5 hemagglutinin gene with simultaneous detection of 3 other poultry respiratory pathogens, Newcastle disease virus (NDV), infectious bronchitis virus (IBV), and infectious laryngotracheitis virus (ILTV). Seven sets of specific oligonucleotide primers were used in this study for the M gene of AIV and hemagglutinin gene of subtypes H7, H9, and H5 of AIV. Three sets of other specific oligonucleotide primers were used for the detection of avian respiratory pathogens other than AIV. The mRT-PCR DNA products were visualized by agarose gel electrophoresis and consisted of DNA fragments of 1,023 bp for M gene of AIV, 149 bp for IBV, 320 bp for NDV, and 647 bp for ILTV. The second set of primers used for m-RT-PCR of H7N3, H9N2, and H5N1 provided DNA products of 300 bp for H7, 456 bp for H5, and 808 bp for H9. The mRT-PCR products for the third format consisted of DNA fragments of 149 bp for IBV, 320 bp for NDV, 647 bp for ILTV, 300 bp for H7, 456 bp for H5, and 808 bp for H9. The sensitivity and specificity of mRT-PCR was determined and the test was found to be sensitive and specific for the detection of AIV and other poultry respiratory pathogens. In this present study, multiplex PCR technique has been developed to simultaneously detect and differentiate the 3 most important subtypes of AIV along with the 3 most common avian respiratory pathogens prevalent in poultry in Pakistan. Therefore, a mRT-PCR that can rapidly differentiate between these pathogens will be very important for the control of disease transmission in poultry and in humans, along with the identification of 3 of the most common respiratory pathogens often seen as mixed infections in poultry, and hence economic losses will be reduced in poultry. PMID:19903950

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

    PubMed Central

    2010-01-01

    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 chromosomal fission, gene

  14. Velocities of fragments from bursting gas reservoirs.

    NASA Technical Reports Server (NTRS)

    Taylor, D. E.; Price, C. F.

    1971-01-01

    A solution is obtained from a simplified approach for the problem of the motion of two fragments driven into a vacuum after rupture of a container filled with gas. Following rupture, the two container fragments are driven in opposite directions. From the separation developed between the moving fragments, the originally contained gas escapes to the vacuum, perpendicular to the direction of motion of the fragments, and with locally sonic velocity. The present solution removes two restrictions of an earlier similar approach: (1) the speed of the gas within the original volume (and consequently, by inference, that of the fragments) is small relative to the sonic escape velocity, and (2) the volume between the separating fragments while they are accelerating undergoes negligible change from the original volume.

  15. Fragmentation of interstellar clouds and star formation

    NASA Technical Reports Server (NTRS)

    Silk, J.

    1982-01-01

    The principal issues are addressed: the fragmentation of molecular clouds into units of stellar mass and the impact of star formation on molecular clouds. The observational evidence for fragmentation is summarized, and the gravitational instability described of a uniform spherical cloud collapsing from rest. The implications are considered of a finite pressure for the minimum fragment mass that is attainable in opacity-limited fragmentation. The role of magnetic fields is discussed in resolving the angular momentum problem and in making the collapse anisotropic, with notable consequences for fragmentation theory. Interactions between fragments are described, with emphasis on the effect of protostellar winds on the ambient cloud matter and on inhibiting further star formation. Such interactions are likely to have profound consequences for regulating the rate of star formation and on the energetics and dynamics of molecular clouds.

  16. Fragmentation of an axially impacted slender rod

    NASA Astrophysics Data System (ADS)

    Ji, W.; Waas, A. M.

    2010-02-01

    Motivated by experimental results on the dynamic buckling and fragmentation of a vertical column impacted by a falling mass, results from an analytical model for dynamic buckling which considers the dynamic interaction between the axial column deformation and the out-of-plane buckling displacements are used to interpret the fragmentation process and the resulting fragment lengths. It is shown that a critical time exists for the rod to undergo fragmentation. At this critical time, the rod deforms in a modulated pattern of waves, setting up the stage for the ensuing fragmentation as a result of induced large curvatures that exceed the critical bending strain of the rod material. The resulting fragment length distributions, which show two characteristics peaks at \\frac{\\lambda}{2} and \\frac{\\lambda}{4} , where λ is a characteristic half-wavelength, are found to compare favorably with the experimental results.

  17. Impact failure and fragmentation properties of metals

    SciTech Connect

    Grady, D.E.; Kipp, M.E.

    1998-03-01

    In the present study we describe the development of an experimental fracture material property test method specific to dynamic fragmentation. Spherical test samples of the metals of interest are subjected to controlled impulsive stress loads by acceleration to high velocities with a light-gas launcher facility and subsequent normal impact on thin plates. Motion, deformation and fragmentation of the test samples are diagnosed with multiple flash radiography methods. The impact plate materials are selected to be transparent to the x-ray method so that only test metal material is imaged. Through a systematic series of such tests both strain-to-failure and fragmentation resistance properties are determined through this experimental method. Fragmentation property data for several steels, copper, aluminum, tantalum and titanium have been obtained to date. Aspects of the dynamic data have been analyzed with computational methods to achieve a better understanding of the processes leading to failure and fragmentation, and to test an existing computational fragmentation model.

  18. Coal char fragmentation during pulverized coal combustion

    SciTech Connect

    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.

  19. Fragmentation statistics from Eulerian hydrocode calculations

    SciTech Connect

    Trucano, T.G.; Grady, D.E.; McGlaun, J.M.

    1989-01-01

    In this paper, we discuss a procedure for computing discrete fragmentation information for terminal ballistics events from the continuum data that emerges from two-dimensional Eulerian hydrocode simulations of these events. The present examples deal with the normal impact of lead cylinders on lead plates at velocities below 1600 m/s. In this regime, the resulting debris is almost exclusively solid lead fragments. We have experimental data of sufficient accuracy to evaluate the extraction of such fragmentation information from code simulations. The problem is interesting because the observed distribution of fragment size would require extreme subgrid resolution in the hydrocode if the statistics were computed directly. Our approach is different. We ask whether or not the general continuum description predicted by the code contains enough information to allow coupling of an analytic fragmentation theory that successfully predicts fragmentation statistics. We believe that this approach is valid, and discuss our current success in matching experimental data. 10 refs., 7 figs., 5 tabs.

  20. Detection of Evolutionarily Distinct Avian Influenza A Viruses in Antarctica

    PubMed Central

    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

    2014-01-01

    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. PMID:24803521

  1. Tooth fragment reattachment: An esthetic, biological restoration

    PubMed Central

    Choudhary, Ajay; Garg, Rakesh; Bhalla, Anindya; Khatri, Rohit Kumar

    2015-01-01

    Coronal fractures of the anterior teeth are a common form of dental trauma. If the original tooth fragment is retained following fracture, reattachment of the fractured fragment to the remaining tooth can provide better and long lasting esthetics, improved function, a positive psychological response, and is a faster and less complicated procedure. This paper reports on coronal tooth fracture case that was successfully treated using adhesive reattachment of fractured fragment and post placement. PMID:25810662

  2. Aggregation of β-amyloid fragments

    NASA Astrophysics Data System (ADS)

    Meinke, Jan H.; Hansmann, Ulrich H. E.

    2007-01-01

    The authors study the folding and aggregation of six chains of the β-amyloid fragment 16-22 using Monte Carlo simulations. While the isolated fragment prefers a helical form at room temperature, in the system of six interacting fragments one observes both parallel and antiparallel β sheets below a crossover temperature Tx≈420K. The antiparallel sheets have lower energy and are therefore more stable. Above the nucleation temperature the aggregate quickly dissolves into widely separated, weakly interacting chains.

  3. Complex fragment emission from hot compound nuclei

    SciTech Connect

    Moretto, L.G.

    1986-03-01

    The experimental evidence for compound nucleus emission of complex fragments at low energies is used to interpret the emission of the same fragments at higher energies. The resulting experimental picture is that of highly excited compound nuclei formed in incomplete fusion processes which decay statistically. In particular, complex fragments appear to be produced mostly through compound nucleus decay. In the appendix a geometric-kinematic theory for incomplete fusion and the associated momentum transfer is outlined. 10 refs., 19 figs.

  4. Cylinder Fragmentation Using Gas Gun Techniques

    NASA Astrophysics Data System (ADS)

    Thornhill, T. F.; Reinhart, W. D.; Chhabildas, L. C.; Grady, D. E.; Wilson, L. T.

    2002-07-01

    In this study an experimental technique for study of cylinder fracture fragmentation characteristics has been developed on a two-stage light gas gun. This test method allows the study of cylinder fracture fragmentation in a laboratory environment under well-controlled loading conditions. Application of this technique allows measure of failure strain, strain rates, expansion velocity, and fragmentation toughness. Results of several experiments on Aermet steel are presented.

  5. Evaluation of cytokine gene expression after avian influenza virus infection in avian cell lines and primary cell cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The innate immune responses elicited by avian influenza virus (AIV) infection has been studied by measuring cytokine gene expression by relative real time PCR (rRT-PCR) in vitro, using both cell lines and primary cell cultures. Continuous cell lines offer advantages over the use of primary cell cult...

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

    PubMed

    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. PMID:26910902

  7. Evaluation and optimization of avian embryos and cell culture methods for efficient isolation and propagation of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surveillance of wild bird populations for avian influenza viruses (AIV) contributes to our understanding of AIV evolution and ecology. Both real-time reverse transcriptase polymerase chain reaction (RRT-PCR) and virus isolation in embryonating chicken eggs (ECE) are standard methods for detecting A...

  8. The dihadron fragmentation function and its evolution

    SciTech Connect

    Majumder, Abhijit; Wang, Xin-Nian

    2004-02-24

    Dihadron fragmentation functions and their evolution arestudied in the process of e+e- annihilation. Under the collinearfactorization approximation and facilitated by the cut-vertex technique,the two hadron inclusive cross section at leading order (LO) is shown tofactorize into a short distance parton cross section and a long distancedihadron fragmentation function. We provide the definition of such adihadron fragmentation function in terms of parton matrix elements andderive its DGLAP evolution equation at leading log. The evolutionequation for the non-singlet quark fragmentation function is solvednumerically with a simple ansatz for the initial condition and resultsare presented for cases of physical interest.

  9. Isotope Labeling Study of Retinal Chromophore Fragmentation.

    PubMed

    Musbat, Lihi; Nihamkin, Maria; Ytzhak, Shany; Hirshfeld, Amiram; Friedman, Noga; Dilger, Jonathan M; Sheves, Mordechai; Toker, Yoni

    2016-04-28

    Previous studies have shown that the gas-phase fragmentation of the retinal chromophore after S0-S1 photoexcitation results in a prominent fragment of mass 248 which cannot be explained by the cleavage of any single bond along the polyene chain. It was therefore theorized that the fragmentation mechanism involves a series of isomerizations and cyclization processes, and two mechanisms for these processes were suggested. Here we used isotope labeling MS-MS to provide conclusive support for the fragmentation mechanism suggested by Coughlan et al. (J. Phys. Chem. Lett. 2014, 5, 3195). PMID:27046667

  10. Electron-impact-induced tryptophan molecule fragmentation

    NASA Astrophysics Data System (ADS)

    Tamuliene, Jelena; Romanova, Liudmila G.; Vukstich, Vasyl S.; Papp, Alexander V.; Snegursky, Alexander V.

    2015-01-01

    The fragmentation of a gas-phase tryptophan molecule by a low-energy (<70 eV) electron impact was studied both experimentally and theoretically. Various positively charged fragments were observed and analyzed. A special attention was paid to the energy characteristics of the ionic fragment yield. The geometrical parameters of the initial molecule rearrangement were also analyzed. The fragmentation observed was due to either a simple bond cleavage or more complex reactions involving molecular rearrangements. Contribution to the Topical Issue "Elementary Processes with Atoms and Molecules in Isolated and Aggregated States", edited by Friedrich Aumayr, Bratislav Marinkovic, Stefan Matejcik, John Tanis and Kurt H. Becker.

  11. Molecular energies from an incremental fragmentation method

    NASA Astrophysics Data System (ADS)

    Meitei, Oinam Romesh; Heßelmann, Andreas

    2016-02-01

    The systematic molecular fragmentation method by Collins and Deev [J. Chem. Phys. 125, 104104 (2006)] has been used to calculate total energies and relative conformational energies for a number of small and extended molecular systems. In contrast to the original approach by Collins, we have tested the accuracy of the fragmentation method by utilising an incremental scheme in which the energies at the lowest level of the fragmentation are calculated on an accurate quantum chemistry level while lower-cost methods are used to correct the low-level energies through a high-level fragmentation. In this work, the fragment energies at the lowest level of fragmentation were calculated using the random-phase approximation (RPA) and two recently developed extensions to the RPA while the incremental corrections at higher levels of the fragmentation were calculated using standard density functional theory (DFT) methods. The complete incremental fragmentation method has been shown to reproduce the supermolecule results with a very good accuracy, almost independent on the molecular type, size, or type of decomposition. The fragmentation method has also been used in conjunction with the DFT-SAPT (symmetry-adapted perturbation theory) method which enables a breakdown of the total nonbonding energy contributions into individual interaction energy terms. Finally, the potential problems of the method connected with the use of capping hydrogen atoms are analysed and two possible solutions are supplied.

  12. Characterization of a conserved extrachromosomal element isolated from the avian malarial parasite Plasmodium gallinaceum.

    PubMed Central

    Joseph, J T; Aldritt, S M; Unnasch, T; Puijalon, O; Wirth, D F

    1989-01-01

    We have identified a conserved, repeated, and highly transcribed DNA element from the avian malarial parasite Plasmodium gallinaceum. The element produced multiple transcripts in both zygotes and asexual blood stages of this parasite. It was found to be highly conserved in all of five malarial species tested and hybridized at reduced stringency to other members of the phylum Apicomplexa, including the genera Babesia, Eimeria, Toxoplasma, and Theileria. The copy number of the element was about 15, and it had a circularly permuted restriction map with a repeat unit length of about 6.2 kilobases. It could be separated from the main genomic DNA by using sucrose gradients and agarose gels, and it migrated separately from the recognized Plasmodium chromosomes on pulse-field gels. In the accompanying paper (S. M. Aldritt, J. T. Joseph, and D. F. Wirth, Mol. Cell. Biol. 9:3614-3620, 1989), evidence is presented that element contains the mitochondrial genes for the protein cytochrome b and a fragment of the large rRNA. We postulate that this element is an episome in the mitochondria of the obligate parasites belonging to the phylum Apicomplexa. Images PMID:2779561

  13. Retardation of cell growth by avian reovirus p17 through the activation of p53 pathway

    SciTech Connect

    Liu, H.-J.; Lin, P.-Y.; Lee, J.-W.; Hsu, H.-Y.; Shih, W.-L. . E-mail: shihwl@mail.tcu.edu.tw

    2005-10-21

    The second open reading frame of avian reovirus S1 gene segment encodes a 17 kDa non-structural protein, named p17. The biological role of p17 is fully unknown so far. Using trypan blue dye exclusion and MTT assay, we demonstrated that the ectopic expression of p17 results in the reduction of viable cell number and cell proliferation rate of Vero, BHK, 293, and HeLa cells. Measurement of LDH activity and DNA fragmentation analysis revealed that p17 expression did not cause cell death or apoptosis. These data indicated that the p17 possessed the growth retardation function. Semi-quantitative RT-PCR and Western blotting revealed that p17-expressing cells induced the expression of CDK inhibitor p21{sup cip1/waf1} in a time- and dose-dependent manner, but the transcripts of CDK inhibitor p15{sup INK4b}, p16{sup INK4a}, or p27{sup kip} were not altered. In the presence of p17, the p53 protein level and p53-driven reporter activity were elevated significantly. Dominant negative p53 alleviated the p21 accumulation, p53 activation, and growth inhibition effect induced by p17. Taken together, these studies revealed a possible intrinsic function of p17 in growth regulation through the activation of p53 and p21{sup cip1/waf1}.

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

    USGS Publications Warehouse

    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.

  15. Outbreak of H7N8 Low Pathogenic Avian Influenza in Commercial Turkeys with Spontaneous Mutation to Highly Pathogenic Avian Influenza.

    PubMed

    Killian, Mary Lea; Kim-Torchetti, Mia; Hines, Nichole; Yingst, Sam; DeLiberto, Thomas; Lee, Dong-Hun

    2016-01-01

    Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises. PMID:27313288

  16. Outbreak of H7N8 Low Pathogenic Avian Influenza in Commercial Turkeys with Spontaneous Mutation to Highly Pathogenic Avian Influenza

    PubMed Central

    Killian, Mary Lea; Hines, Nichole; Yingst, Sam; DeLiberto, Thomas; Lee, Dong-Hun

    2016-01-01

    Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises. PMID:27313288

  17. Comparative pathology of H5N1 highly pathogenic avian influenza virus infection in avian species in the Orders Anseriformes and Charadriiformes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirteen species of ducks, geese, swans and gulls present in the North American wild bird populations were inoculated intranasally with A/Whooper Swan/Mongolia/244/05 (H5N1) avian influenza virus to evaluate the range of viral shedding and pathology within these two avian orders. Based on mortality...

  18. Statistical theory of fragmentation processes

    SciTech Connect

    Dienes, J.K.

    1984-01-01

    The goal of the work reviewed here is a theory of material behavior accounting for the average deformation that results from the opening, shear, growth and coalescence of an ensemble of microcracks. A concomitant is the calculation of permeability from crack structure. The first part of this paper summarizes previous developments. In particular, the initial work on this problem made use of a linear Liouville equation to characterize the change in crack distribution resulting from crack growth and coalescence. Straightforward analytic solutions to this equation were possible because the mean free path of cracks was assumed constant. Though this assumption is useful for the early stages of crack growth, increasing crack size reduces the mean free path in the later stages of fragmentation. This problem is addressed in the second part of this paper. The governing (nonlinear) Liouville equation is derived therein, and it is shown that it can be reduced to an ordinary differential equation of third order involving only a single parameter, ..beta... This equation has now been solved numerically to determine the limiting value of the mean free path as a function of ..beta.., and the results are presented in graphical form. In the third part of this paper prospects for further developments are briefly discussed.

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

    SciTech Connect

    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.

  20. Sizing of DNA fragments by flow cytometry

    SciTech Connect

    Johnson, M.E.; Goodwin, P.M.; Ambrose, W.P.; Martin, J.C.; Marrone, B.L.; Jett, J.H.; Keller, R.A.

    1993-02-01

    Individual, stained DNA fragments were sized using a modified flow cytometer with high sensitivity fluorescence detection. The fluorescent intercalating dye ethidium homodimer was used to stain stoichiometrically lambda phage DNA and a Kpn I digest of lambda DNA. Stained, individual fragments of DNA were passed through a low average power, focused, mode-locked laser beam, and the fluorescence from each fragment was collected and quantified. Time-gated detection was used to discriminate against Raman scattering from the water solvent. The fluorescence burst from each fragment was related directly to its length, thus providing a means to size small quantities of kilobase lengths of DNA quickly. Improvements of several orders of magnitude in analysis time and sample size over current gel electrophoresis techniques were realized. Fragments of 17.1,29.9, and 48.5 thousand base pairs were well resolved, and were sized in 164 seconds. Less than one pg of DNA was required for analysis. We have demonstrated sizing of individual, stained DNA fragments with resolution approaching that of gel electrophoresis for moderately large fragments, but with significant reductions in the analysis time and the amount of sample required. Furthermore, system response is linear with DNA fragment length, in contrast to the logarithmic response in gel electrophoresis. There exists the potential to perform this sizing using relatively simple instrumentation, i.e. a continuous wave laser of low power and current mode detection.

  1. Sizing of DNA fragments by flow cytometry

    SciTech Connect

    Johnson, M.E.; Goodwin, P.M.; Ambrose, W.P.; Martin, J.C.; Marrone, B.L.; Jett, J.H.; Keller, R.A.

    1993-01-01

    Individual, stained DNA fragments were sized using a modified flow cytometer with high sensitivity fluorescence detection. The fluorescent intercalating dye ethidium homodimer was used to stain stoichiometrically lambda phage DNA and a Kpn I digest of lambda DNA. Stained, individual fragments of DNA were passed through a low average power, focused, mode-locked laser beam, and the fluorescence from each fragment was collected and quantified. Time-gated detection was used to discriminate against Raman scattering from the water solvent. The fluorescence burst from each fragment was related directly to its length, thus providing a means to size small quantities of kilobase lengths of DNA quickly. Improvements of several orders of magnitude in analysis time and sample size over current gel electrophoresis techniques were realized. Fragments of 17.1,29.9, and 48.5 thousand base pairs were well resolved, and were sized in 164 seconds. Less than one pg of DNA was required for analysis. We have demonstrated sizing of individual, stained DNA fragments with resolution approaching that of gel electrophoresis for moderately large fragments, but with significant reductions in the analysis time and the amount of sample required. Furthermore, system response is linear with DNA fragment length, in contrast to the logarithmic response in gel electrophoresis. There exists the potential to perform this sizing using relatively simple instrumentation, i.e. a continuous wave laser of low power and current mode detection.

  2. Waves in fragmented geomaterials with impact attenuation

    NASA Astrophysics Data System (ADS)

    Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Attenuation of waves in geomaterials, such as seismic waves is usually attributed to energy dissipation due to the presence of viscous fluid and/or viscous cement between the constituents. In fragmented geomaterials such as blocky rock mass there is another possible source of energy dissipation - impacting between the fragments. This can be characterised by the coefficient of restitution, which is the ratio between the rotational velocities after and before the impact. In particular, this manifests itself in the process of mutual rotations of the fragments/blocks, whereby in the process of oscillation different ends of the contacting faces of the fragments are impacting. During the rotational oscillations the energy dissipation is concentrated in the neutral position that is the one in which the relative rotation between two fragments is zero. We show that in a simple system of two fragments this dissipation is equivalent, in a long run, to the presence of viscous damper between the fragments (the Voigt model of visco-elasticity). Generalisation of this concept to the material consisting of many fragments leads to a Voigt model of wave propagation where the attenuation coefficient is proportional to the logarithm of restitution coefficient. The waves in such a medium show slight dispersion caused by damping and strong dependence of the attenuation on the wave frequency.

  3. Sizing of DNA fragments by flow cytometry

    NASA Astrophysics Data System (ADS)

    Johnson, Mitchell E.; Goodwin, Peter M.; Ambrose, W. Patrick; Martin, John C.; Marrone, Babetta L.; Jett, James H.; Keller, Richard A.

    1993-06-01

    Individual, stained DNA fragments were sized using a modified flow cytometer with high sensitivity fluorescence detection. The fluorescent intercalating dye ethidium homodimer was used to stain stoichiometrically lambda phage DNA and a Kpn I digest of lambda DNA. Stained, individual fragments of DNA were passed through a low average power, focused, mode-locked laser beam, and the fluorescence from each fragment was collected and quantified. Time-gated detection was used to discriminate against Raman scattering from the water solvent. The fluorescence burst from each fragment was related directly to its length, thus providing a means to size small quantities of kilobase lengths of DNA quickly. Improvements of several orders of magnitude in analysis time and sample size over current gel electrophoresis techniques were realized. Fragments of 17.1, 29.9, and 48.5 thousand base pairs were well resolved, and were sized in 164 seconds. Less than one pg of DNA was required for analysis.

  4. Linking avian communities and avian influenza ecology in southern Africa using epidemiological functional groups

    PubMed Central

    2012-01-01

    The ecology of pathogens, and particularly their emergence in multi-host systems, is complex. New approaches are needed to reduce superficial complexities to a level that still allows scientists to analyse underlying and more fundamental processes. One promising approach for simplification is to use an epidemiological-function classification to describe ecological diversity in a way that relates directly to pathogen dynamics. In this article, we develop and apply the epidemiological functional group (EFG) concept to explore the relationships between wild bird communities and avian influenza virus (AIV) in three ecosystems in southern Africa. Using a two year dataset that combined bird counts and bimonthly sampling for AIV, we allocated each bird species to a set of EFGs that captured two overarching epidemiological functions: the capacity of species to maintain AIV in the system, and their potential to introduce the virus. Comparing AIV prevalence between EFGs suggested that the hypothesis that anseriforms (ducks) and charadriiforms (waders) drive AIV epidemiology cannot entirely explain the high prevalence observed in some EFGs. If anseriforms do play an important role in AIV dynamics in each of the three ecosystems, the role of other species in the local maintenance of AIV cannot be ruled out. The EFG concept thus helped us to identify gaps in knowledge and to highlight understudied bird groups that might play a role in AIV epidemiology. In general, the use of EFGs has potential for generating a range of valuable insights in epidemiology, just as functional group approaches have done in ecology. PMID:23101696

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

    PubMed Central

    Lutful Kabir, S. M.

    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 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. PMID:20195435

  6. Response of avian communities to herbicide-induced vegetation changes

    USGS Publications Warehouse

    Morrison, M.L.; Meslow, E.C.

    1984-01-01

    The relationships between avian communities and herbicide modification of vegetation were analyzed on early-growth clear-cuts in western Oregon that had received phenoxy herbicide treatment 1 or 4 years previously. For both 1 and 4 years post-spray, vegetation development was greater in the third height interval (> 3.0 m) on untreated sites. All measures of vegetative diversity on untreated sites exceeded those on treated sites. Overall density and diversity of birds were similar between treated and untreated sites. Several bird species altered their foraging behavior on treated sites, i.e., birds using deciduous trees increased use of shrubs on treated sites. The primary effect of herbicide application was a reduction in the complexity of vegetation, a condition due primarity to the removal of deciduous trees. Small patches of deciduous trees scattered in clear-cuts treated with phenoxy herbicides can maintain an avian community similar to that on untreated sites.

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

    SciTech Connect

    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.

  8. Monitoring low density avian populations: An example using Mountain Plovers

    USGS Publications Warehouse

    Dreitz, V.J.; Lukacs, P.M.; Knopf, F.L.

    2006-01-01

    Declines in avian populations highlight a need for rigorous, broad-scale monitoring programs to document trends in avian populations that occur in low densities across expansive landscapes. Accounting for the spatial variation and variation in detection probability inherent to monitoring programs is thought to be effort-intensive and time-consuming. We determined the feasibility of the analytical method developed by Royle and Nichols (2003), which uses presence-absence (detection-non-detection) field data, to estimate abundance of Mountain Plovers (Charadrius montanus) per sampling unit in agricultural fields, grassland, and prairie dog habitat in eastern Colorado. Field methods were easy to implement and results suggest that the analytical method provides valuable insight into population patterning among habitats. Mountain Plover abundance was highest in prairie dog habitat, slightly lower in agricultural fields, and substantially lower in grassland. These results provided valuable insight to focus future research into Mountain Plover ecology and conservation. ?? The Cooper Ornithological Society 2006.

  9. State transitions and decoherence in the avian compass.

    PubMed

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

    2015-05-01

    The radical pair model has been successful in explaining behavioral characteristics of the geomagnetic compass believed to underlie the navigation capability of certain avian species. In this study, the spin dynamics of the radical pair model and decoherence therein are interpreted from a microscopic state transition point of view. This helps to elucidate the interplay between the hyperfine and Zeeman interactions that enables the avian compass and clarify the distinctive effects of nuclear and environmental decoherence on it. Three regimes have been identified for the strength of the hyperfine interaction with respect to that of the geomagnetic Zeeman. It is found that the compass is likely to function in the large hyperfine interaction regime. Using a quantum information theoretic quantifier of coherence, we find that nuclear decoherence induces new structure in the spin dynamics for intermediate hyperfine interaction strength. On the other hand, environmental decoherence-modeled by two different noise models-seems to disrupt the compass action. PMID:26066201

  10. Quantitation of avian RNA tumor virus reverse transcriptase by radioimmunoassay.

    PubMed Central

    Panet, A; Baltimore, D; Hanafusa, T

    1975-01-01

    A radioimmunoassay was developed that can detect and quantitate 3 ng or more of the avian RNA tumor virus reverse transcriptase. The assay detected no antigenic sites in Rous sarcoma virus alpha virions or in virions of a murine RNA tumor virus. About 70 molecules of reverse transcriptase were found per virion of avian myleloblastosis virus with this assay or with an assay based on antibody inhibition of enzymatic activity. The assay detected about 270 ng of enzyme per mg of cell protein in virus-producing cells; uninfected cells had much less antigenic material but contained some determinants able to displace radioactive antigen. No additional antigenic determinants on reverse transcriptase could be detected that were not found on the separated alpha subunit of the enzyme. Although sevenfold less sensitive than enzymatic activity as a measure of reverse transcriptase, the radioimmunoassay can detect antigen using small amounts of protein and in the presence of inhibtors. Images PMID:48558

  11. State transitions and decoherence in the avian compass

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

    The radical pair model has been successful in explaining behavioral characteristics of the geomagnetic compass believed to underlie the navigation capability of certain avian species. In this study, the spin dynamics of the radical pair model and decoherence therein are interpreted from a microscopic state transition point of view. This helps to elucidate the interplay between the hyperfine and Zeeman interactions that enables the avian compass and clarify the distinctive effects of nuclear and environmental decoherence on it. Three regimes have been identified for the strength of the hyperfine interaction with respect to that of the geomagnetic Zeeman. It is found that the compass is likely to function in the large hyperfine interaction regime. Using a quantum information theoretic quantifier of coherence, we find that nuclear decoherence induces new structure in the spin dynamics for intermediate hyperfine interaction strength. On the other hand, environmental decoherence—modeled by two different noise models—seems to disrupt the compass action.

  12. Avian pox in blue-fronted Amazon parrots.

    PubMed

    McDonald, S E; Lowenstine, L J; Ardans, A A

    1981-12-01

    During a 1-month period at a quarantine station, an epornitic of avian pox occurred in blue-fronted Amazon parrots (Amazona aestiva). Clinical signs included conjunctivitis, blepharitis, and varying degrees of anorexia and respiratory distress. Lesions included periocular ulcerations and scabs and necrotic plaques in the oral cavity. Histologically, the lesions consisted of epithelial hyperplasia, secondary inflammatory changes, and eosinophilic inclusions which, by electron microscopy, were shown to contain poxvirus. When chicken embryos were inoculated with material from eyelid scabs and pharyngeal plaques, lesions of avian pox developed on the chorioallantoic membrane. The death rate of infected birds was high because of secondary bacterial and fungal infections, but uncomplicated cases were usually self-limiting. Periocular lesions also developed in 2 other species of psittacine birds housed in the same facility. PMID:6276348

  13. Persistence of Highly Pathogenic Avian Influenza Viruses in Natural Ecosystems

    PubMed Central

    Feare, Chris J.; Renaud, François; Thomas, Frédéric; Gauthier-Clerc, Michel

    2010-01-01

    Understanding of ecologic factors favoring emergence and maintenance of highly pathogenic avian influenza (HPAI) viruses is limited. Although low pathogenic avian influenza viruses persist and evolve in wild populations, HPAI viruses evolve in domestic birds and cause economically serious epizootics that only occasionally infect wild populations. We propose that evolutionary ecology considerations can explain this apparent paradox. Host structure and transmission possibilities differ considerably between wild and domestic birds and are likely to be major determinants of virulence. Because viral fitness is highly dependent on host survival and dispersal in nature, virulent forms are unlikely to persist in wild populations if they kill hosts quickly or affect predation risk or migratory performance. Interhost transmission in water has evolved in low pathogenic influenza viruses in wild waterfowl populations. However, oropharyngeal shedding and transmission by aerosols appear more efficient for HPAI viruses among domestic birds. PMID:20587174

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

    PubMed

    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. PMID:24491922

  15. Missing Fragments: Detecting Cooperative Binding in Fragment-Based Drug Design

    PubMed Central

    2012-01-01

    The aim of fragment-based drug design (FBDD) is to identify molecular fragments that bind to alternate subsites within a given binding pocket leading to cooperative binding when linked. In this study, the binding of fragments to human phenylethanolamine N-methyltransferase is used to illustrate how (a) current protocols may fail to detect fragments that bind cooperatively, (b) theoretical approaches can be used to validate potential hits, and (c) apparent false positives obtained when screening against cocktails of fragments may in fact indicate promising leads. PMID:24900472

  16. Missing fragments: detecting cooperative binding in fragment-based drug design.

    PubMed

    Nair, Pramod C; Malde, Alpeshkumar K; Drinkwater, Nyssa; Mark, Alan E

    2012-04-12

    The aim of fragment-based drug design (FBDD) is to identify molecular fragments that bind to alternate subsites within a given binding pocket leading to cooperative binding when linked. In this study, the binding of fragments to human phenylethanolamine N-methyltransferase is used to illustrate how (a) current protocols may fail to detect fragments that bind cooperatively, (b) theoretical approaches can be used to validate potential hits, and (c) apparent false positives obtained when screening against cocktails of fragments may in fact indicate promising leads. PMID:24900472

  17. Avian Visual Behavior and the Organization of the Telencephalon

    PubMed Central

    Shimizu, Toru; Patton, Tadd B.; Husband, Scott A.

    2010-01-01

    Birds have excellent visual abilities that are comparable or superior to those of primates, but how the bird brain solves complex visual problems is poorly understood. More specifically, we lack knowledge about how such superb abilities are used in nature and how the brain, especially the telencephalon, is organized to process visual information. Here we review the results of several studies that examine the organization of the avian telencephalon and the relevance of visual abilities to avian social and reproductive behavior. Video playback and photographic stimuli show that birds can detect and evaluate subtle differences in local facial features of potential mates in a fashion similar to that of primates. These techniques have also revealed that birds do not attend well to global configural changes in the face, suggesting a fundamental difference between birds and primates in face perception. The telencephalon plays a major role in the visual and visuo-cognitive abilities of birds and primates, and anatomical data suggest that these animals may share similar organizational characteristics in the visual telencephalon. As is true in the primate cerebral cortex, different visual features are processed separately in the avian telencephalon where separate channels are organized in the anterior-posterior axis roughly parallel to the major laminae. Furthermore, the efferent projections from the primary visual telencephalon form an extensive column-like continuum involving the dorsolateral pallium and the lateral basal ganglia. Such a column-like organization may exist not only for vision, but for other sensory modalities and even for a continuum that links sensory and limbic areas of the avian brain. Behavioral and neural studies must be integrated in order to understand how birds have developed their amazing visual systems through 150 million years of evolution. PMID:20733296

  18. MHC haplotype involvement in avian resistance to an ectoparasite.

    PubMed

    Owen, Jeb P; Delany, Mary E; Mullens, Bradley A

    2008-10-01

    Research on immune function in evolutionary ecology has frequently focused on avian ectoparasites (e.g., mites and lice). However, host immunogenetics involved with bird resistance to ectoparasites has not been determined. The critical role of the major histocompatibility complex (MHC) in adaptive immunity and high genetic variation found within the MHC make this gene complex useful for exploring the immunogenetic basis for bird resistance to ectoparasites. The objective of this study was to determine if the avian MHC influenced resistance to a blood-feeding ectoparasite. Four congenic lines of chickens, differing only at the MHC, were comparatively infested with a cosmopolitan ectoparasite of birds-northern fowl mite (NFM)-which is also a serious pest species of poultry. Mite infestations were monitored over time and mite densities (weekly and maximum) were compared among lines. Chickens with the MHC haplotype B21 were relatively resistant to NFM, compared with birds in the B15 congenic line (P < 0.02). To test for similar effects in an outbred genetic background, a separate experiment was performed with 107 commercial chickens (white leghorn, W-36 strain) infested with NFM. Hens were genotyped using a MHC microsatellite marker (LEI0258) and associations between MHC haplotype and NFM density were tested. The highest peak NFM populations occurred more often on hens with the B15 haplotype versus the B21 haplotype (P = 0.012), which supported the results of the congenic study. These data indicate the avian MHC influences ectoparasite resistance, which is relevant to disease ecology and avian-ectoparasite interaction. PMID:18626638

  19. Nesting behaviour influences species-specific gas exchange across avian eggshells

    PubMed Central

    Portugal, Steven J.; Maurer, Golo; Thomas, Gavin H.; Hauber, Mark E.; Grim, Tomáš; Cassey, Phillip

    2014-01-01

    Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (GH2O) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell GH2O and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in GH2O has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between GH2O and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher GH2O than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher GH2O than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the GH2O are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher GH2O to overcome this constraint and still achieve optimal water

  20. Avian Conservation Practices Strengthen Ecosystem Services in California Vineyards

    PubMed Central

    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. PMID:22096555

  1. Emergence of fatal avian influenza in New England harbor seals

    USGS Publications Warehouse

    Anthony, S.J.; St. Leger, J. A.; Pugliares, K.; Ip, H.S.; Chan, J.M.; Carpenter, Z.W.; Navarrete-Macias, I.; Sanchez-Leon, M.; Saliki, J.T.; Pedersen, J.; Karesh, W.; Daszak, P.; Rabadan, R.; Rowles, T.; Lipkin, W.I.

    2012-01-01

    From September to December 2011, 162 New England harbor seals died in an outbreak of pneumonia. Sequence analysis of postmortem samples revealed the presence of an avian H3N8 influenza A virus, similar to a virus circulating in North American waterfowl since at least 2002 but with mutations that indicate recent adaption to mammalian hosts. These include a D701N mutation in the viral PB2 protein, previously reported in highly pathogenic H5N1 avian influenza viruses infecting people. Lectin staining and agglutination assays indicated the presence of the avian-preferred SAα-2,3 and mammalian SAα-2,6 receptors in seal respiratory tract, and the ability of the virus to agglutinate erythrocytes bearing either the SAα-2,3 or the SAα-2,6 receptor. The emergence of this A/harbor seal/Massachusetts/1/2011 virus may herald the appearance of an H3N8 influenza clade with potential for persistence and cross-species transmission.

  2. The cuticle modulates ultraviolet reflectance of avian eggshells

    PubMed Central

    Fecheyr-Lippens, Daphne C.; Igic, Branislav; D'Alba, Liliana; Hanley, Daniel; Verdes, Aida; Holford, Mande; Waterhouse, Geoffrey I. N.; Grim, Tomas; Hauber, Mark E.; Shawkey, Matthew D.

    2015-01-01

    ABSTRACT 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. PMID:25964661

  3. Avian ecosystem functions are influenced by small mammal ecosystem engineering

    PubMed Central

    2013-01-01

    Background Birds are important mobile link species that contribute to landscape-scale patterns by means of pollination, seed dispersal, and predation. Birds are often associated with habitats modified by small mammal ecosystem engineers. We investigated whether birds prefer to forage on degu (Octodon degus) runways by comparing their foraging effort across sites with a range of runway densities, including sites without runways. We measured granivory by granivorous and omnivorous birds at Rinconada de Maipú, central Chile. As a measure of potential bird foraging on insects, we sampled invertebrate prey richness and abundance across the same sites. We then quantified an index of plot-scale functional diversity due to avian foraging at the patch scale. Results We recorded that birds found food sources sooner and ate more at sites with higher densities of degu runways, cururo mounds, trees, and fewer shrubs. These sites also had higher invertebrate prey richness but lower invertebrate prey abundance. This implies that omnivorous birds, and possibly insectivorous birds, forage for invertebrates in the same plots with high degu runway densities where granivory takes place. In an exploratory analysis we also found that plot-scale functional diversity for four avian ecosystem functions were moderately to weakly correllated to expected ecosystem function outcomes at the plot scale. Conclusions Degu ecosystem engineering affects the behavior of avian mobile link species and is thus correlated with ecosystem functioning at relatively small spatial scales. PMID:24359802

  4. A simple vitrification method for cryobanking avian testicular tissue.

    PubMed

    Liu, J; Cheng, K M; Purdy, P H; Silversides, F G

    2012-12-01

    Cryopreservation of testicular tissue is a promising method of preserving male reproductive potential for avian species. This study was conducted to assess whether a vitrification method can be used to preserve avian testicular tissue, using the Japanese quail (Coturnix japonica) as a model. A simple vitrification method that included dimethyl sulphoxide, ethylene glycol, and sucrose as cryoprotective agents, and allowed the storage of tissue in a sealed macrotube was applied to the testicular tissue from 1-wk-old Japanese quail. The vitrified tissue was warmed at room temperature or at 40°C. After warming, tissue was implanted onto the chorioallantoic membrane of 8- to 9-d-old chicken embryos and the vascularization of the grafts was evaluated. When compared with fresh tissue, the tissue that had been warmed at 40°C showed no difference in vascularization. The tissue that had been warmed at room temperature was significantly less vascularized than the fresh tissue. Vitrification of testicular tissue and storage in macrotubes provide a promising model for preservation and recovery of male germplasm of avian species. PMID:23155032

  5. The Role of Environmental Transmission in Recurrent Avian Influenza Epidemics

    PubMed Central

    Breban, Romulus; Drake, John M.; Stallknecht, David E.; Rohani, Pejman

    2009-01-01

    Avian influenza virus (AIV) persists in North American wild waterfowl, exhibiting major outbreaks every 2–4 years. Attempts to explain the patterns of periodicity and persistence using simple direct transmission models are unsuccessful. Motivated by empirical evidence, we examine the contribution of an overlooked AIV transmission mode: environmental transmission. It is known that infectious birds shed large concentrations of virions in the environment, where virions may persist for a long time. We thus propose that, in addition to direct fecal/oral transmission, birds may become infected by ingesting virions that have long persisted in the environment. We design a new host–pathogen model that combines within-season transmission dynamics, between-season migration and reproduction, and environmental variation. Analysis of the model yields three major results. First, environmental transmission provides a persistence mechanism within small communities where epidemics cannot be sustained by direct transmission only (i.e., communities smaller than the critical community size). Second, environmental transmission offers a parsimonious explanation of the 2–4 year periodicity of avian influenza epidemics. Third, very low levels of environmental transmission (i.e., few cases per year) are sufficient for avian influenza to persist in populations where it would otherwise vanish. PMID:19360126

  6. The cuticle modulates ultraviolet reflectance of avian eggshells.

    PubMed

    Fecheyr-Lippens, Daphne C; Igic, Branislav; D'Alba, Liliana; Hanley, Daniel; Verdes, Aida; Holford, Mande; Waterhouse, Geoffrey I N; Grim, Tomas; Hauber, Mark E; Shawkey, Matthew D

    2015-01-01

    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. PMID:25964661

  7. Early Arterial Differentiation and Patterning in the Avian Embryo Model

    PubMed Central

    Garriock, Robert J; Mikawa, Takashi

    2011-01-01

    Of the many models to study vascular biology the avian embryo remains an informative and powerful model system that has provided important insights into endothelial cell recruitment, assembly and remodeling during development of the circulatory system. This review highlights several discoveries in the avian system that show how arterial patterning is regulated using the model of dorsal aortae development along the embryo midline during gastrulation and neurulation. These discoveries were made possible through spatially and temporally controlled gain-of-function experiments that provided direct evidence that BMP signaling plays a pivotal role in vascular recruitment, patterning and remodeling and that Notch-signaling recruits vascular precursor cells to the dorsal aortae. Importantly, BMP ligands are broadly expressed throughout embryos but BMP signaling activation region is spatially defined by precisely regulated expression of BMP antagonists. These discoveries provide insight into how signaling, both positive and negative, regulate vascular patterning. This review also illustrates similarities of early arterial patterning along the embryonic midline in amniotes both avian and mammalians including human, evolutionarily specialized from non-amniotes such as fish and frog. PMID:22020129

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

    PubMed Central

    Koh, GCH; Wong, TY; Cheong, SK; Koh, DSQ

    2008-01-01

    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. PMID:19014538

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

    NASA Astrophysics Data System (ADS)

    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.

  10. New Perspectives on the Ontogeny and Evolution of Avian Locomotion.

    PubMed

    Heers, Ashley M

    2016-09-01

    Close correspondence between form and function is a central tenet of natural selection. One of the most striking, textbook cases for form-function congruence is the evolution of flight and the body plan of birds: compared with other tetrapods, extant adult birds have highly modified integuments and skeletons, and it has traditionally been assumed that many of these modifications are adaptations or exaptations for flight. However, developing birds that lack many of the morphological signatures of flight capacity nevertheless use their developing wings for a variety of flapping behaviors, such as wing-assisted incline running and even brief flight. Immature birds thereby demonstrate that rudimentary "flight" apparatuses are more functional than traditional assumptions about form-function relationships would predict. Here, I review the ontogeny of avian locomotion, highlighting how the developmental acquisition of flight in extant birds can improve our understanding of form-function relationships in the avian body plan, and provide insight into the evolutionary origin of flight among extinct non-avian theropod dinosaurs. PMID:27371381

  11. Dinosaurian growth patterns and rapid avian growth rates.

    PubMed

    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. PMID:11473315

  12. Revised Nomenclature for Avian Telencephalon and Some Related Brainstem Nuclei

    PubMed Central

    REINER, ANTON; PERKEL, DAVID J.; BRUCE, LAURA L.; BUTLER, ANN B.; CSILLAG, ANDRÁS; KUENZEL, WAYNE; MEDINA, LORETA; PAXINOS, GEORGE; SHIMIZU, TORU; STRIEDTER, GEORG; WILD, MARTIN; BALL, GREGORY F.; DURAND, SARAH; GÜTÜRKÜN, ONUR; LEE, DIANE W.; MELLO, CLAUDIO V.; POWERS, ALICE; WHITE, STEPHANIE A.; HOUGH, GERALD; KUBIKOVA, LUBICA; SMULDERS, TOM V.; WADA, KAZUHIRO; DUGAS-FORD, JENNIFER; HUSBAND, SCOTT; YAMAMOTO, KEIKO; YU, JING; SIANG, CONNIE; JARVIS, ERICH D.

    2008-01-01

    The standard nomenclature that has been used for many telencephalic and related brainstem structures in birds is based on flawed assumptions of homology to mammals. In particular, the outdated terminology implies that most of the avian telencephalon is a hypertrophied basal ganglia, when it is now clear that most of the avian telencephalon is neurochemically, hodologically, and functionally comparable to the mammalian neocortex, claustrum, and pallial amygdala (all of which derive from the pallial sector of the developing telencephalon). Recognizing that this promotes misunderstanding of the functional organization of avian brains and their evolutionary relationship to mammalian brains, avian brain specialists began discussions to rectify this problem, culminating in the Avian Brain Nomenclature Forum held at Duke University in July 2002, which approved a new terminology for avian telencephalon and some allied brainstem cell groups. Details of this new terminology are presented here, as is a rationale for each name change and evidence for any homologies implied by the new names. Revisions for the brainstem focused on vocal control, catecholaminergic, cholinergic, and basal ganglia-related nuclei. For example, the Forum recognized that the hypoglossal nucleus had been incorrectly identified as the nucleus intermedius in the Karten and Hodos (1967) pigeon brain atlas, and what was identified as the hypoglossal nucleus in that atlas should instead be called the supraspinal nucleus. The locus ceruleus of this and other avian atlases was noted to consist of a caudal noradrenergic part homologous to the mammalian locus coeruleus and a rostral region corresponding to the mammalian A8 dopaminergic cell group. The midbrain dopaminergic cell group in birds known as the nucleus tegmenti pedunculopontinus pars compacta was recognized as homologous to the mammalian substantia nigra pars compacta and was renamed accordingly; a group of γ-aminobutyric acid (GABA)ergic neurons at

  13. Avian assemblages in the lower Missouri river floodplain

    USGS Publications Warehouse

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

    2009-01-01

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

  14. A PCR test for avian malaria in Hawaiian birds.

    PubMed

    Feldman, R A; Freed, L A; Cann, R L

    1995-12-01

    The decline of native Hawaiian forest birds since European contact is attributed to factors ranging from habitat destruction to interactions with introduced species. Remaining populations of Hawaiian honeycreepers (Fringillidae: Drepanidinae) are most abundant and diverse in high elevation refuges above the normal range of disease-carrying mosquitoes. Challenge experiments suggest that honeycreepers are highly susceptible to avian malaria (Plasmodium sp.) but resistance exists in some species. In order to detect low levels of malarial infection and quantify prevalence of Plasmodium in high elevation natural populations of Hawaiian birds, a polymerase chain reaction (PCR) based diagnostic test was developed that identifies rRNA genes of Plasmodium in avian blood samples. Quantitative competitive PCR (QC-PCR) experiments indicate that the detection limit of our test is an order of magnitude greater than that reported for human malaria DNA blot tests. Compared with standard histological methods, the PCR test detected a higher prevalence of diseased birds at mid-elevations. Malaria was detected in three species of native birds living in a high elevation wildlife refuge on the island of Hawaii and in four species from Maui. Our results show that avian malaria is more widespread in Hawaiian forests than previously thought, a finding that has important conservation implications for these threatened species. PMID:8564006

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

    USGS Publications Warehouse

    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 (<30 cm) water, thereby attracting different guilds of birds. Grain not collected during harvest (i.e. waste rice) is typically the most abundant potential food of birds in rice fields, with estimates of seed mass from North America ranging from 66672 kg/ha. Although initially abundant after harvest, waste rice availability can be temporally limited. Few abundance estimates for other foods, such as vertebrate prey or forage vegetation, exist for rice fields. Outside North America, Europe and Japan, little is known about abundance and importance of any avian food in rice fields. Currently, flooding rice fields after harvest is the best known management practice to attract and benefit birds. Studies from North America indicate specific agricultural practices (e.g. burning stubble) may increase use and improve access to food resources. Evaluating and implementing management practices that are ecologically sustainable, increase food for birds and are agronomically beneficial should be global priorities to integrate rice production and avian conservation. Finally, land area devoted to rice agriculture appears to be stable in the USA, declining in China, and largely unquantified in many regions. Monitoring trends in riceland area may provide information to guide avian conservation planning in rice-agriculture ecosystems.

  16. Protective roles of free avian respiratory macrophages in captive birds.

    PubMed

    Mutua, Mbuvi P; Muya, Shadrack; Gicheru, Muita M

    2016-01-01

    In the mammalian lung, respiratory macrophages provide front line defense against invading pathogens and particulate matter. In birds, respiratory macrophages are known as free avian respiratory macrophages (FARM) and a dearth of the cells in the avian lung has been purported to foreordain a weak first line of pulmonary defense, a condition associated with high mortality of domestic birds occasioned by respiratory inflictions. Avian pulmonary mechanisms including a three tiered aerodynamic filtration system, tight epithelial junctions and an efficient mucociliary escalator system have been known to supplement FARM protective roles. Current studies, however, report FARM to exhibit an exceptionally efficient phagocytic capacity and are effective in elimination of invading pathogens. In this review, we also report on effects of selective synthetic peroxisome proliferator activated receptor gamma (PPAR γ) agonists on non phlogistic phagocytic properties in the FARM. To develop effective therapeutic interventions targeting FARM in treatment and management of respiratory disease conditions in the poultry, further studies are required to fully understand the role of FARM in innate and adaptive immune responses. PMID:27306902

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

    PubMed

    Bailleul, Alida M; Hall, Brian K; Horner, John R

    2013-01-01

    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. PMID:23418610

  18. Secondary Cartilage Revealed in a Non-Avian Dinosaur Embryo

    PubMed Central

    Bailleul, Alida M.; Hall, Brian K.; Horner, John R.

    2013-01-01

    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. PMID:23418610

  19. Impact fragmentation of aluminum reactive materials

    NASA Astrophysics Data System (ADS)

    Hooper, Joseph P.

    2012-08-01

    We report the fragmentation of brittle, granular aluminum spheres following high velocity impact (0.5-2.0 km/s) on thin steel plates. These spheres, machined from isostatically pressed aluminum powder, represent a prototypical metallic reactive material. The fragments generated by the impacts are collected in a soft-catch apparatus and analyzed down to a length scale of 44μm. With increasing velocity, there is a transition from an exponential Poisson-process fragment distribution with a characteristic length scale to a power-law behavior indicative of scale-invariance. A normalized power-law distribution with a finite size cutoff is introduced and used to analyze the number and mass distributions of the recovered fragments. At high impact velocities, the power-law behavior dominates the distribution and the power-law exponent is identical to the universal value for brittle fragmentation discussed in recent works. The length scale at which the power-law behavior decays is consistent with the idea that the length of side microbranches or damage zones from primary cracks is governing this cutoff. The transition in fragment distribution at high strain-rates also implies a significant increase in small fragments that can rapidly combust in an ambient atmosphere.

  20. Heavy ion fragmentation experiments at the bevatron

    NASA Technical Reports Server (NTRS)

    Heckman, H. H.

    1976-01-01

    Collaborative research efforts to study the fragmentation processes of heavy nuclei in matter using heavy ion beams of the Bevatron/Bevalac are described. The goal of the program is to obtain the single particle inclusive spectra of secondary nuclei produced at 0 deg by the fragmentation of heavy ion beam projectiles. The process being examined is B+T yields F + anything, where B is the beam nucleus, T is the target nucleus, and F is the detected fragment. The fragments F are isotopically identified by experimental procedures involving magnetic analysis, energy loss and time-of-flight measurements. Effects were also made to: (a) study processes of heavy nuclei in matter, (b) measure the total and partial production cross section for all isotopes, (c) test the applicability of high energy multiparticle interaction theory to nuclear fragmentation, (d) apply the cross section data and fragmentation probabilities to cosmic ray transport theory, and (e) search for systematic behavior of fragment production as a means to improve existing semi-empirical theories of cross-sections.

  1. On Disciplinary Fragmentation and Scientific Progress

    PubMed Central

    Balietti, Stefano; Mäs, Michael; Helbing, Dirk

    2015-01-01

    Why are some scientific disciplines, such as sociology and psychology, more fragmented into conflicting schools of thought than other fields, such as physics and biology? Furthermore, why does high fragmentation tend to coincide with limited scientific progress? We analyzed a formal model where scientists seek to identify the correct answer to a research question. Each scientist is influenced by three forces: (i) signals received from the correct answer to the question; (ii) peer influence; and (iii) noise. We observed the emergence of different macroscopic patterns of collective exploration, and studied how the three forces affect the degree to which disciplines fall apart into divergent fragments, or so-called “schools of thought”. We conducted two simulation experiments where we tested (A) whether the three forces foster or hamper progress, and (B) whether disciplinary fragmentation causally affects scientific progress and vice versa. We found that fragmentation critically limits scientific progress. Strikingly, there is no effect in the opposite causal direction. What is more, our results shows that at the heart of the mechanisms driving scientific progress we find (i) social interactions, and (ii) peer disagreement. In fact, fragmentation is increased and progress limited if the simulated scientists are open to influence only by peers with very similar views, or when within-school diversity is lost. Finally, disciplines where the scientists received strong signals from the correct answer were less fragmented and experienced faster progress. We discuss model’s implications for the design of social institutions fostering interdisciplinarity and participation in science. PMID:25790025

  2. Anionic derivatives of uracil: fragmentation and reactivity.

    PubMed

    Cole, Callie A; Wang, Zhe-Chen; Snow, Theodore P; Bierbaum, Veronica M

    2014-09-01

    Uracil is an essential biomolecule for terrestrial life, yet its prebiotic formation mechanisms have proven elusive for decades. Meteorites have been shown to contain uracil and the interstellar abundance of aromatic species and nitrogen-containing molecules is well established, providing support for uracil's presence in the interstellar medium (ISM). The ion chemistry of uracil may provide clues to its prebiotic synthesis and role in the origin of life. The fragmentation of biomolecules provides valuable insights into their formation. Previous research focused primarily on the fragmentation and reactivity of cations derived from uracil. In this study, we explore deprotonated uracil-5-carboxylic acid and its anionic fragments to elucidate novel reagents of uracil formation and to characterize the reactivity of uracil's anionic derivatives. The structures of these fragments are identified through theoretical calculations, further fragmentation, experimental acidity bracketing, and reactivity with several detected and potential interstellar species (SO2, OCS, CS2, NO, N2O, CO, NH3, O2, and C2H4). Fragmentation is achieved through collision induced dissociation (CID) in a commercial ion trap mass spectrometer, and all reaction rate constants are measured using a modification of this instrument. Experimental data are supported by theoretical calculations at the B3LYP/6-311++G(d,p) level of theory. Lastly, the astrochemical implications of the observed fragmentation and reaction processes are discussed. PMID:25036757

  3. On disciplinary fragmentation and scientific progress.

    PubMed

    Balietti, Stefano; Mäs, Michael; Helbing, Dirk

    2015-01-01

    Why are some scientific disciplines, such as sociology and psychology, more fragmented into conflicting schools of thought than other fields, such as physics and biology? Furthermore, why does high fragmentation tend to coincide with limited scientific progress? We analyzed a formal model where scientists seek to identify the correct answer to a research question. Each scientist is influenced by three forces: (i) signals received from the correct answer to the question; (ii) peer influence; and (iii) noise. We observed the emergence of different macroscopic patterns of collective exploration, and studied how the three forces affect the degree to which disciplines fall apart into divergent fragments, or so-called "schools of thought". We conducted two simulation experiments where we tested (A) whether the three forces foster or hamper progress, and (B) whether disciplinary fragmentation causally affects scientific progress and vice versa. We found that fragmentation critically limits scientific progress. Strikingly, there is no effect in the opposite causal direction. What is more, our results shows that at the heart of the mechanisms driving scientific progress we find (i) social interactions, and (ii) peer disagreement. In fact, fragmentation is increased and progress limited if the simulated scientists are open to influence only by peers with very similar views, or when within-school diversity is lost. Finally, disciplines where the scientists received strong signals from the correct answer were less fragmented and experienced faster progress. We discuss model's implications for the design of social institutions fostering interdisciplinarity and participation in science. PMID:25790025

  4. A Stochastic Model of DNA Fragments Rejoining

    PubMed Central

    Li, Yongfeng; Qian, Hong; Wang, Ya; Cucinotta, Francis A.

    2012-01-01

    When cells are exposed to ionizing radiation, DNA damages in the form of single strand breaks (SSBs), double strand breaks (DSBs), base damage or their combinations are frequent events. It is known that the complexity and severity of DNA damage depends on the quality of radiation, and the microscopic dose deposited in small segments of DNA, which is often related to the linear transfer energy (LET) of the radiation. Experimental studies have suggested that under the same dose, high LET radiation induces more small DNA fragments than low-LET radiation, which affects Ku efficiently binding with DNA end and might be a main reason for high-LET radiation induced RBE [1] since DNA DSB is a major cause for radiation-induced cell death. In this work, we proposed a mathematical model of DNA fragments rejoining according to non-homologous end joining (NHEJ) mechanism. By conducting Gillespie's stochastic simulation, we found several factors that impact the efficiency of DNA fragments rejoining. Our results demonstrated that aberrant DNA damage repair can result predominantly from the occurrence of a spatial distribution of DSBs leading to short DNA fragments. Because of the low efficiency that short DNA fragments recruit repair protein and release the protein residue after fragments rejoining, Ku-dependent NHEJ is significantly interfered with short fragments. Overall, our work suggests that inhibiting the Ku-dependent NHEJ may significantly contribute to the increased efficiency for cell death and mutation observed for high LET radiation. PMID:23028515

  5. Introduction to fragment-based drug discovery.

    PubMed

    Erlanson, Daniel A

    2012-01-01

    Fragment-based drug discovery (FBDD) has emerged in the past decade as a powerful tool for discovering drug leads. The approach first identifies starting points: very small molecules (fragments) that are about half the size of typical drugs. These fragments are then expanded or linked together to generate drug leads. Although the origins of the technique date back some 30 years, it was only in the mid-1990s that experimental techniques became sufficiently sensitive and rapid for the concept to be become practical. Since that time, the field has exploded: FBDD has played a role in discovery of at least 18 drugs that have entered the clinic, and practitioners of FBDD can be found throughout the world in both academia and industry. Literally dozens of reviews have been published on various aspects of FBDD or on the field as a whole, as have three books (Jahnke and Erlanson, Fragment-based approaches in drug discovery, 2006; Zartler and Shapiro, Fragment-based drug discovery: a practical approach, 2008; Kuo, Fragment based drug design: tools, practical approaches, and examples, 2011). However, this chapter will assume that the reader is approaching the field with little prior knowledge. It will introduce some of the key concepts, set the stage for the chapters to follow, and demonstrate how X-ray crystallography plays a central role in fragment identification and advancement. PMID:21695633

  6. "Diabodies": small bivalent and bispecific antibody fragments.

    PubMed Central

    Holliger, P; Prospero, T; Winter, G

    1993-01-01

    Bivalent and bispecific antibodies and their fragments have immense potential for practical application. Here we describe the design of small antibody fragments with two antigen-binding sites. The fragments comprise a heavy-chain variable domain (VH) connected to a light-chain variable domain (VL) on the same polypeptide chain (VH-VL). By using a linker that is too short to allow pairing between the two domains on the same chain, the domains are forced to pair with the complementary domains of another chain and create two antigen-binding sites. As indicated by a computer graphic model of the dimers, the two pairs of domains can pack together with the antigen-binding sites pointing in opposite directions. The dimeric antibody fragments, or "diabodies," can be designed for bivalent or bispecific interactions. Starting from the monoclonal antibodies NQ11.7.22 (NQ11) and D1.3 directed against the hapten phenyloxazolone and hen egg lysozyme, respectively, we built bivalent fragments (VHNQ11-VLNQ11)2 and (VHD1.3-VLD1.3)2 and bispecific fragments VHNQ11-VLD1.3 and VHD1.3-VLNQ11. The fragments were expressed by secretion from bacteria and shown to bind specifically to the hapten and/or antigen. Those with 5- and 15-residue linkers had similar binding affinities to the parent antibodies, but a fragment with the VH domain joined directly to the VL domain was found to have slower dissociation kinetics and an improved affinity for hapten. Diabodies offer a ready means of constructing small bivalent and bispecific antibody fragments in bacteria. Images Fig. 1 Fig. 3 PMID:8341653

  7. Aggregation of beta-amyloid fragments.

    PubMed

    Meinke, Jan H; Hansmann, Ulrich H E

    2007-01-01

    The authors study the folding and aggregation of six chains of the beta-amyloid fragment 16-22 using Monte Carlo simulations. While the isolated fragment prefers a helical form at room temperature, in the system of six interacting fragments one observes both parallel and antiparallel beta sheets below a crossover temperature T(x) approximately equal to 420 K. The antiparallel sheets have lower energy and are therefore more stable. Above the nucleation temperature the aggregate quickly dissolves into widely separated, weakly interacting chains. PMID:17212510

  8. Simulation of collisional fragmentation with explosives

    NASA Technical Reports Server (NTRS)

    Housen, Kevin

    1993-01-01

    For practical reasons, experimental studies of collisional fragmentation must at times rely on explosives to fragment a target body. For example, Housen et al., described experiments in which spheres were fragmented in a pressurized atmosphere. Explosives were used because impacts could not be performed in the pressure chamber. Explosives can also be used to study targets much larger than those which can be disrupted by conventional light-gas guns, thereby allowing size- and rate-effects to be investigated. The purpose of this study is to determine the charge burial depth required to simulate various aspects of collisions.

  9. Bone fragments a body can make

    SciTech Connect

    Stout, S.D.; Ross, L.M. Jr. )

    1991-05-01

    Data obtained from various analytical techniques applied to a number of small bone fragments recovered from a crime scene were used to provide evidence for the occurrence of a fatality. Microscopic and histomorphometric analyses confirmed that the fragments were from a human skull. X-ray microanalysis of darkened areas on the bone fragments revealed a chemical signature that matched the chemical signature of a shotgun pellet recovered at the scene of the crime. The above findings supported the deoxyribonucleic acid (DNA) fingerprint evidence which, along with other evidence, was used to convict a man for the murder of his wife, even though her body was never recovered.

  10. The singular coagulation equation with multiple fragmentation

    NASA Astrophysics Data System (ADS)

    Saha, Jitraj; Kumar, Jitendra

    2015-06-01

    In this paper, we prove the global existence and uniqueness of the solutions to the initial-value problem for the coagulation-fragmentation equation with singular coagulation kernel and multiple fragmentation kernel. The solution obtained in this case also satisfies the mass conservation law. The proof is based on strong convergence methods applied to suitably chosen unbounded coagulation kernels having singularities in both the coordinate axes and satisfying certain growth conditions, which can possibly reach up to a quadratic growth at infinity, and the fragmentation kernel covers a very large class of unbounded functions.

  11. A general theory of turbulent fragmentation

    NASA Astrophysics Data System (ADS)

    Hopkins, Philip F.

    2013-04-01

    We develop an analytic framework to understand fragmentation in turbulent, self-gravitating media. In previous work, we showed how some properties of turbulence can be predicted by application of the excursion-set formalism. Here, we generalize this to understand fully time-dependent gravo-turbulent fragmentation and collapse. We show that turbulent systems are always gravitationally unstable in a probabilistic sense. The fragmentation mass spectrum, size-mass-density-linewidth relations of collapsing objects, their correlation functions and clustering, the range of spatial scales over which fragmentation occurs, and the time-dependent rate of collapse/fragmentation (as a function of size/mass) are analytically predictable. We show how these depend on bulk properties of turbulence; fragmentation is promoted at higher Mach numbers and shallower power spectra. We also generalize the model to properly include rotation, complicated gas equations of state, collapsing/expanding backgrounds, magnetic fields, intermittency and non-normal statistics (with inherently correlated fluctuations). This allows us to formally derive how fragmentation is suppressed with `stiffer' equations of state (e.g. higher polytropic index γ) or differently driven turbulence (solenoidal versus compressive). The suppression appears at an `effective sonic scale' where b {M}(R_s, ρ _crit[R_s])≈ 1, with ρcrit being the (scale-dependent) critical density for fragmentation. Gas becomes stable against collapse below this scale for γ > 4/3; however, fragmentation still occurs on larger scales. We show that the scale-free nature of turbulence and gravity generically drives mass spectra and correlation functions towards universal shapes (observed in a wide variety of astrophysical phenomena), with weak residual dependence on many properties of the media. We find that correlated fluctuations on different scales, non-Gaussian density distributions and intermittency have surprisingly small effects on

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

    PubMed

    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

  13. Replication and Adaptive Mutations of Low Pathogenic Avian Influenza Viruses in Tracheal Organ Cultures of Different Avian Species

    PubMed Central

    Petersen, Henning; Matrosovich, Mikhail; Pleschka, Stephan; Rautenschlein, Silke

    2012-01-01

    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. PMID:22912693

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

    SciTech Connect

    Vazquez-Iglesias, Lorena; Lostale-Seijo, Irene; Martinez-Costas, Jose; Benavente, Javier

    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.

  15. Adaptation of avian influenza A (H6N1) virus from avian to human receptor-binding preference.

    PubMed

    Wang, Fei; Qi, Jianxun; Bi, Yuhai; Zhang, Wei; Wang, Min; Zhang, Baorong; Wang, Ming; Liu, Jinhua; Yan, Jinghua; Shi, Yi; Gao, George F

    2015-06-12

    The receptor-binding specificity of influenza A viruses is a major determinant for the host tropism of the virus, which enables interspecies transmission. In 2013, the first human case of infection with avian influenza A (H6N1) virus was reported in Taiwan. To gather evidence concerning the epidemic potential of H6 subtype viruses, we performed comprehensive analysis of receptor-binding properties of Taiwan-isolated H6 HAs from 1972 to 2013. We propose that the receptor-binding properties of Taiwan-isolated H6 HAs have undergone three major stages: initially avian receptor-binding preference, secondarily obtaining human receptor-binding capacity, and recently human receptor-binding preference, which has been confirmed by receptor-binding assessment of three representative virus isolates. Mutagenesis work revealed that E190V and G228S substitutions are important to acquire the human receptor-binding capacity, and the P186L substitution could reduce the binding to avian receptor. Further structural analysis revealed how the P186L substitution in the receptor-binding site of HA determines the receptor-binding preference change. We conclude that the human-infecting H6N1 evolved into a human receptor preference. PMID:25940072

  16. An avian-only Filippov model incorporating culling of both susceptible and infected birds in combating avian influenza.

    PubMed

    Chong, Nyuk Sian; Dionne, Benoit; Smith, Robert

    2016-09-01

    Depopulation of birds has always been an effective method not only to control the transmission of avian influenza in bird populations but also to eliminate influenza viruses. We introduce a Filippov avian-only model with culling of susceptible and/or infected birds. For each susceptible threshold level [Formula: see text], we derive the phase portrait for the dynamical system as we vary the infected threshold level [Formula: see text], focusing on the existence of endemic states; the endemic states are represented by real equilibria, pseudoequilibria and pseudo-attractors. We show generically that all solutions of this model will approach one of the endemic states. Our results suggest that the spread of avian influenza in bird populations is tolerable if the trajectories converge to the equilibrium point that lies in the region below the threshold level [Formula: see text] or if they converge to one of the pseudoequilibria or a pseudo-attractor on the surface of discontinuity. However, we have to cull birds whenever the solution of this model converges to an equilibrium point that lies in the region above the threshold level [Formula: see text] in order to control the outbreak. Hence a good threshold policy is required to combat bird flu successfully and to prevent overkilling birds. PMID:26865385

  17. History of on-orbit satellite fragmentations

    NASA Technical Reports Server (NTRS)

    Johnson, N. L.; Gabbard, J. R.; Devere, G. T.; Johnson, E. E.

    1984-01-01

    The causes of on-orbit fragmentations are varied and may be intentional or accidental. The cause of many fragmentations remains unknown. While a few cases are currently under investigation as on-orbit collision candidates, man is directly responsible for the vast majority of artificial debris polluting the near-Earth space environment. It should be emphasized that the number of fragments listed with each event in this document represent only those debris officially cataloged by NORAD. Each known on-orbit satellite fragementation is described within this document in module format. Also listed are pertinent characteristics of each fragmentation event. Comments regarding the nature of the satellite and additional details of the events are given.

  18. FOREST FRAGMENTATION AS AN ECONOMIC INDICATOR

    EPA Science Inventory

    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 ...

  19. Dispersal and extinction in fragmented landscapes.

    PubMed Central

    Thomas, C D

    2000-01-01

    Evolutionary and population dynamics models suggest that the migration rate will affect the probability of survival in fragmented landscapes. Using data for butterfly species in the fragmented British landscape and in immediately adjoining areas of the European continent, this paper shows that species of intermediate mobility have declined most, followed by those of low mobility, whereas high-mobility species are generally surviving well. Compared to the more sedentary species, species of intermediate mobility require relatively large areas where they breed at slightly lower local densities. Intermediate mobility species have probably fared badly through a combination of metapopulation (extinction and colonization) dynamics and the mortality of migrating individuals which fail to find new habitats in fragmented landscapes. Habitat fragmentation is likely to result in the non-random extinction of populations and species characterized by different levels of dispersal, although the details are likely to depend on the taxa, habitats and regions considered. PMID:10687818

  20. The NJL Model for Quark Fragmentation Functions

    SciTech Connect

    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.