Science.gov

Sample records for serendipitous backyard hybridization

  1. Backyard Taxonomy.

    ERIC Educational Resources Information Center

    Gotsch, Margaret; Harris, Shannon

    1990-01-01

    Described is a backyard activity that can be used to introduce children to the divisions of the plant and animal kingdoms in their local environment. Preparation, procedures and followup are discussed. Background information on taxonomy and two activity cards are provided. (CW)

  2. Serendipitous Stencil Prints

    ERIC Educational Resources Information Center

    Tam, Jeff

    2008-01-01

    Printing, stamping, and rubbings are enjoyed by all ages, and the image-making capabilities of this media are endless and very spontaneous. In printmaking, images can be repeated, overlapped, inked in various colors, cut up, reassembled, and manipulated. Students find these methods to be engaging and serendipitous. This lesson, designed for eighth…

  3. Backyard Infrared Trapping

    ERIC Educational Resources Information Center

    Gibbons, Thomas C.

    2014-01-01

    In this time of concern over climate change due to the atmospheric greenhouse effect, teachers often choose to extend relevant classroom work by the use of physical models to test statements. Here we describe an activity in which inexpensive backyard models made from cardboard boxes covered with various household transparent materials allow…

  4. Backyard Conservation: Bringing Conservation from the Countryside to Your Backyard.

    ERIC Educational Resources Information Center

    Wildlife Habitat Council, Silver Spring, MD.

    This guide highlights 10 conservation activities, adapted from farms and ranches, that can be used in the backyard. Each activity provides background information and instructions on how to complete the activity. The activities concern: (1) tree planting; (2) wildlife habitat; (3) backyard ponds; (4) nutrient management; (5) terracing; (6) water…

  5. Backyard Infrared Trapping

    NASA Astrophysics Data System (ADS)

    Gibbons, Thomas C.

    2014-12-01

    In this time of concern over climate change due to the atmospheric greenhouse effect,1 teachers often choose to extend relevant classroom work by the use of physical models to test statements. Here we describe an activity in which inexpensive backyard models made from cardboard boxes covered with various household transparent materials allow students to explore how transmission of visible and infrared light can affect the temperature.2 Our basic setup is shown schematically in Fig. 1, in which a black-lined box with a thermometer in contact with the bottom is covered with transparent (to visible light) household materials.

  6. Freud, Poetry and Serendipitous Parapraxes.

    ERIC Educational Resources Information Center

    de Chumaceiro, Cora L. Diaz

    1996-01-01

    Discusses an overlooked example in everyday life of serendipitous parapraxes in the recall of poetry presented by Freud in 1907. Notes that its principles are applicable to clinical and educational research and practice, taking into account contemporary transference-countertransference dynamics. (SR)

  7. Representation of Serendipitous Scientific Data

    NASA Technical Reports Server (NTRS)

    James, Mark

    2006-01-01

    A computer program defines and implements an innovative kind of data structure than can be used for representing information derived from serendipitous discoveries made via collection of scientific data on long exploratory spacecraft missions. Data structures capable of collecting any kind of data can easily be implemented in advance, but the task of designing a fixed and efficient data structure suitable for processing raw data into useful information and taking advantage of serendipitous scientific discovery is becoming increasingly difficult as missions go deeper into space. The present software eases the task by enabling definition of arbitrarily complex data structures that can adapt at run time as raw data are transformed into other types of information. This software runs on a variety of computers, and can be distributed in either source code or binary code form. It must be run in conjunction with any one of a number of Lisp compilers that are available commercially or as shareware. It has no specific memory requirements and depends upon the other software with which it is used. This program is implemented as a library that is called by, and becomes folded into, the other software with which it is used.

  8. Epidemiologic characterization of Colorado backyard bird flocks.

    PubMed

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had < 50 birds); consist primarily of layer chickens (85.49% of flocks), show chickens (32.18% of flocks), and waterfowl (34.07% of flocks); and are primarily owned for food (meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds. PMID:22856180

  9. Zoonotic Public Health Hazards in Backyard Chickens.

    PubMed

    Pohjola, L; Nykäsenoja, S; Kivistö, R; Soveri, T; Huovilainen, A; Hänninen, M L; Fredriksson-Ahomaa, M

    2016-08-01

    Backyard poultry has become increasingly popular in industrialized countries. In addition to keeping chickens for eggs and meat, owners often treat the birds as pets. However, several pathogenic enteric bacteria have the potential for zoonotic transmission from poultry to humans but very little is known about the occurrence of zoonotic pathogens in backyard flocks. The occurrence and the antimicrobial resistance of Salmonella enterica, Campylobacter spp., Listeria monocytogenes and enteropathogenic Yersinia spp. was studied in 51 voluntary backyard chicken farms in Finland during October 2012 and January 2013. Campylobacter isolates were further characterized by pulsed-field gel electrophoresis (PFGE), and the occurrence of ESBL/AmpC-producing E. coli was investigated. The findings from this study indicate that backyard chickens are a reservoir of Campylobacter jejuni strains and a potential source of C. jejuni infection for humans. Backyard chickens can also carry L. monocytogenes, although their role as a primary reservoir is questionable. Campylobacter coli, Yersinia pseudotuberculosis and Salmonella enterica were only found sporadically in the faecal and environmental samples of backyard poultry in Finland. No Yersinia enterocolitica carrying the virulence plasmid was isolated. All pathogens were highly susceptible to most of the antimicrobials studied. Only a few AmpC- and no ESBL-producing E. coli were found. PMID:26752227

  10. Cataclysmic Variables in the Backyard

    NASA Astrophysics Data System (ADS)

    Patterson, J.

    2012-06-01

    (Abstract only) The last decade has seen plummeting prices and significant advances in CCD-camera and smart-telescope technology, reaching all the way to the humblest of telescopes. There are now thousands of well-equipped amateur astronomers interested in using their telescopes for research, and many hundreds already doing so in coordinated campaigns. Variable star science has benefited tremendously. Since it's always dark and always clear somewhere, coordinated photometry can accumulate nearly 24-hour coverage - and since the observers own their telescopes, very long campaigns are feasible, with little worry about weather. I'll describe one network of observers, the Center for Backyard Astrophysics (CBA). The telescope apertures are 20-50 cm, enabling good signal-to-noise and time resolution down to V=18. We organize campaigns of time-series photometry of cataclysmic variables (novae, dwarf novae, magnetic variables, some X-ray binaries) - and routinely achieve thousand-hour campaigns with no significant aliasing, since the telescopes are distributed around the world. This enables sensitive searches for periodic signals, extending even to long time scales (months). We now produce most of the world's supply of accretion-disk precession periods, and keep close watch on all the other clocks in cataclysmic variables (orbit, white-dwarf rotation and pulsation, and quasiperiodic oscillations).

  11. Cataclysmic Variables in the Backyard

    NASA Astrophysics Data System (ADS)

    Patterson, Joseph

    2011-05-01

    The last decade has seen plummeting prices and significant advances in CCD-camera and smart-telescope technology, reaching all the way to the humblest of telescopes. There are now thousands of well-equipped amateur astronomers interested in using their telescopes for research, and many hundreds already doing so in coordinated campaigns. Variable star science has benefited tremendously. Since it's always dark and always clear somewhere, coordinated photometry can accumulate nearly 24-hour coverage... and since the observers own their telescopes, very long campaigns are feasible, with little worry about weather. I'll describe one network of observers, the Center for Backyard Astrophysics (CBA). The telescope apertures are 20-50 cm, enabling good signal-to-noise and time resolution down to V=18. We organize campaigns of time-series photometry of cataclysmic variables (novae, dwarf novae, magnetic variables, some X-ray binaries) - and routinely achieve thousand-hour campaigns with no significant aliasing, since the telescopes are distributed around the world. This enables sensitive searches for periodic signals, extending even to long time scales (months). We now produce most of the world's supply of accretion-disk precession periods, and keep close watch on all the other clocks in cataclysmic variables (orbit, white-dwarf rotation and pulsation, and quasiperiodic oscillations).

  12. EXURBAN BACKYARDS: HOTSPOTS FOR ECOSYSTEM SERVICES?

    EPA Science Inventory

    The broad goal of this research is to identify ecosystem services provided by exurban residential landscapes and make inferences about practices that may mitigate negative environmental impacts of sprawl. Because of the more private nature of backyards, it is hypothesized t...

  13. Screening for Salmonella in backyard chickens.

    PubMed

    Manning, Johanna; Gole, Vaibhav; Chousalkar, Kapil

    2015-06-15

    Salmonellosis is a significant zoonotic disease which has a considerable economic impact on the egg layer industry. There is limited information about the prevalence of Salmonella spp. in backyard chickens. The current study was conducted to determine the prevalence of Salmonella in backyard chickens, and the associated virulence of any serovars identified. Hundred and fifteen pooled samples from 30 backyard flocks in South Australia were screened. Four flocks tested positive for Salmonella spp. The overall Salmonella isolation rate in the current study was 10.4%. The estimated prevalence at individual bird level was 0.02% (95% CI 0.025-0.975). The serovars isolated were Salmonella Agona, Salmonella subsp 2 ser 21:z10:z6 (Wandsbek) and Salmonella Bovismorbificans. All Salmonella isolates tested positive for the prgH, orfL and spiC genes. The Salmonella subsp 2 ser 21:z10:z6 (Wandsbek) had the most antibiotic resistance, being resistant to ampicillin and cephalothin and having intermediate resistance to florphenicol. All of the Salmonella Agona had intermediate resistance to the ampicillin, while the Salmonella Bovismorbificans were susceptible to all antibiotics tested. With the increased interest of keeping backyard chickens, the current study highlights the zoonotic risk from Salmonella spp. associated with home flocks. PMID:25899620

  14. Cherenkov radiation as a serendipitous phenomenon

    NASA Astrophysics Data System (ADS)

    Kadmensky, S. G.

    2015-05-01

    A brief account is given of P A Cherenkov's Voronezh years, a period during which the future Nobel laureate in physics attended school (in the village of Novaya Chigla near Voronezh) and studied at Voronezh State University. The history of the serendipitous discovery of the radiation which was to be named after him is described and its importance for modern science is discussed. Possible modern approaches are considered to explain — without using the concept of 'cold nuclear synthesis' — some other unexpected experimental results on the nonthermonuclear fusion of light nuclei stimulated by electron beams and by laser and gamma radiations.

  15. The NuSTAR Serendipitous Survey

    NASA Astrophysics Data System (ADS)

    Lansbury, George B.; NuSTAR

    2015-01-01

    A great breakthrough in studying the cosmic X-ray background (CXB) population is the Nuclear Spectroscopic Telescope Array (NuSTAR), the first focusing X-ray observatory with high sensitivity at > 10 keV. Here we present results from the NuSTAR serendipitous survey, the largest area (~7 deg2) component of the NuSTAR extragalactic survey programme. The source statistics are relatively good for a high energy X-ray survey, with ~150 detections and ~100 spectroscopically identified sources to-date. Studying the X-ray emission at > 10 keV, where X-rays from the central black hole are relatively unabsorbed, allows intrinsic properties such as column densities and luminosities to be well constrained. The X-ray analysis is supplemented by broad-band UV to mid-IR spectral energy distribution (SED) analyses. The dominant source population sampled by the NuSTAR serendipitous survey is quasars with L(10-40)keV > 1044 erg/s. This population is broadly similar to the population of nearby high-energy selected AGNs sampled by Swift/BAT, but scaled up in luminosity and mass.

  16. 45 CFR 674.7 - Exception for serendipitous finds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ANTARCTIC METEORITES § 674.7 Exception for serendipitous finds. A person who makes a serendipitous discovery of a meteorite in Antarctica which could not have been reasonably anticipated, may collect the meteorite for scientific research purposes, provided that the meteorite is collected in the manner...

  17. 45 CFR 674.7 - Exception for serendipitous finds.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ANTARCTIC METEORITES § 674.7 Exception for serendipitous finds. A person who makes a serendipitous discovery of a meteorite in Antarctica which could not have been reasonably anticipated, may collect the meteorite for scientific research purposes, provided that the meteorite is collected in the manner...

  18. 45 CFR 674.7 - Exception for serendipitous finds.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ANTARCTIC METEORITES § 674.7 Exception for serendipitous finds. A person who makes a serendipitous discovery of a meteorite in Antarctica which could not have been reasonably anticipated, may collect the meteorite for scientific research purposes, provided that the meteorite is collected in the manner...

  19. The Cosmic Web in Our Own Backyard

    NASA Astrophysics Data System (ADS)

    Ibata, Rodrigo A.; Lewis, Geraint F.

    2008-01-01

    On the largest scales, matter is strung out on an intricate pattern known as the cosmic web. The tendrils of this web should reach right into our own cosmic backyard, lacing the Galactic halo with lumps of dark matter. The search for these lumps, lit up by stars that formed within them, is a major astronomical endeavor, although it has failed to find the huge expected population. Is this a dark matter crisis, or does it provide clues to the complexities of gas physics in the early universe? New technologies in the coming decade will reveal the answer.

  20. The cosmic web in our own backyard.

    PubMed

    Ibata, Rodrigo A; Lewis, Geraint F

    2008-01-01

    On the largest scales, matter is strung out on an intricate pattern known as the cosmic web. The tendrils of this web should reach right into our own cosmic backyard, lacing the Galactic halo with lumps of dark matter. The search for these lumps, lit up by stars that formed within them, is a major astronomical endeavor, although it has failed to find the huge expected population. Is this a dark matter crisis, or does it provide clues to the complexities of gas physics in the early universe? New technologies in the coming decade will reveal the answer. PMID:18174430

  1. Serendipitous asteroid observations by OSIRIS/Rosetta

    NASA Astrophysics Data System (ADS)

    Carry, B.; Berthier, J.; Vachier, F.; Küppers, M.

    2012-09-01

    In recent years, many efforts have been undertaken to extract the astrometry, photometry, and colors of Solar System Small Bodies from large surveys and widefield camera, such as the SDSS Moving Object Catalog [2] or EuroNear [3]. Since 2006, the IMCCE provides a service, called SkyBoT [1], that list all the Solar System Objects in a given field of view for a given epoch. Such a tool is of high interest for any data mining purpose of large archives. We will present an extension of SkyBoT from ground-based to space-based geometries. As a demonstration, we will present our search for serendipitously observed asteroids in the data archive of the OSIRIS instrument on-board the ESA Rosetta mission.

  2. Spark, an application based on Serendipitous Knowledge Discovery.

    PubMed

    Workman, T Elizabeth; Fiszman, Marcelo; Cairelli, Michael J; Nahl, Diane; Rindflesch, Thomas C

    2016-04-01

    Findings from information-seeking behavior research can inform application development. In this report we provide a system description of Spark, an application based on findings from Serendipitous Knowledge Discovery studies and data structures known as semantic predications. Background information and the previously published IF-SKD model (outlining Serendipitous Knowledge Discovery in online environments) illustrate the potential use of information-seeking behavior in application design. A detailed overview of the Spark system illustrates how methodologies in design and retrieval functionality enable production of semantic predication graphs tailored to evoke Serendipitous Knowledge Discovery in users. PMID:26732995

  3. Hybrid organic-inorganic chlorozincate and a molecular zinc complex involving the in situ formed imidazo[1,5-a]pyridinium cation: serendipitous oxidative cyclization, structures and photophysical properties.

    PubMed

    Buvaylo, Elena A; Kokozay, Vladimir N; Linnik, Rostyslav P; Vassilyeva, Olga Yu; Skelton, Brian W

    2015-08-14

    Two novel compounds, the organic-inorganic hybrid [L](2)[ZnCl(4)] (1) and the coordination complex LZnCl(3) (2), where L is the 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridinium cation, were prepared using the oxidative condensation-cyclization of 2-pyridinecarbaldehyde and CH(3)NH(2)·HCl in methanol in the presence of Zn(2+) cations. The metal-free interaction of the organic components afforded the salt [L][Cl]·1.5H(2)O (3). The use of methylamine hydrochloride instead of its aqueous solution is believed to be responsible for the cyclocondensation with the formation of L instead of the expected Schiff base ligand. Compounds 1-3 have been obtained as single crystals and characterized by elemental analysis, IR, NMR spectroscopy, and single-crystal X-ray diffraction techniques. The structure of 1 is described as layers of cations and anions stacked along the c-axis, with the minimum ZnZn distance being 8.435 Å inside a layer. In the crystal lattice of 3, the cations are arranged in stacks propagating along the a-axis; the 1D H-bonding polymer built of chloride ions and water molecules runs parallel to a column of stacked cations. The organic cations in salts 1 and 3 show various patterns of π-π stacking. The discrete molecular structure of 2 shows coordination of a Zn atom to the N(pyridyl) atom, which enables one of the chloride atoms attached to the metal centre to interact with a π-system of the positively charged imidazolium ring. Numerous C-HCl contacts in a 1-3 are seen as space-filling van der Waals interactions of minor importance in determining crystal packing. The (1)H NMR studies suggest that the Zn-N coordination found in the solid-state structure of 2 is not retained in dmso, and 1, 2 and 3 are completely dissociated in solution. The emission spectra of 1 and 2 (λ(max) = 455 and 445 nm, respectively) exhibit red-shifts of fluorescence wavelength when compared to 3 and differ in the shapes and maxima of the emission as well as in relative

  4. Serendipitous findings while researching oxygen free radicals.

    PubMed

    Floyd, Robert A

    2009-04-15

    This review is based on the honor of receiving the Discovery Award from the Society of Free Radical Biology and Medicine. The review is reflective and presents our thinking that led to experiments that yielded novel observations. Critical questioning of our understanding of oxygen free radicals in biomedical problems led us to use and develop more direct and extremely sensitive methods. This included nitrone free radical spin trapping and HPLC-electrochemical detection. This technology led to the pioneering use of salicylate to trap hydroxyl free radicals and show increased flux in ischemia/reperfused brain regions and also to first sensitively detect 8-hydroxyl-2-deoxyguanosine in oxidatively damaged DNA and help assess its role in cancer development. We demonstrated that methylene blue (MB) photoinduces formation of 8-hydroxyguanine in DNA and RNA and discovered that MB sensitively photoinactivates RNA viruses, including HIV and the West Nile virus. Studies in experimental stroke led us serendipitously to discover that alpha-phenyl-tert-butylnitrone (PBN) was neuroprotective if given after the stroke. This led to extensive commercial development of NXY-059, a PBN derivative, for the treatment of stroke. More recently we discovered that PBN nitrones have potent anti-cancer activity and are active in preventing hearing loss caused by acute acoustical trauma. PMID:19439210

  5. The Madagascar Bloom: A serendipitous study

    NASA Astrophysics Data System (ADS)

    Srokosz, M. A.; Quartly, G. D.

    2013-01-01

    The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon, and ends. It has been observed and studied using satellite ocean color observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made serendipitously on a cruise in February 2005. These show clearly for the first time the simultaneous existence of a deep chlorophyll maximum at ~70-110 m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature [seen in Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite ocean color data]. The observations also show the modulation of the biological signature at the surface by the eddy field but not of the deep chlorophyll maximum. Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. The surface bloom seen in the SeaWiFS data is confined to the shallow (~30 m) mixed layer. It is hypothesized that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

  6. The Madagascar Bloom - a serendipitous study

    NASA Astrophysics Data System (ADS)

    Srokosz, M. A.; Quartly, G.

    2012-12-01

    The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar, exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon and ends. It has been observed and studied using satellite ocean colour observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made on a cruise in February 2005 serendipitously. These show clearly for the first time the existence of both a deep chlorophyll maximum at ~70-110m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature (seen in SeaWiFS satellite ocean colour data). The observations also show the modulation of biological signature at the surface by the eddy field, but not apparently of the deep chlorophyll maximum. In situ observations indicate that Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. In addition, SeaSoar Optical Plankton Counter (OPC), temperature and salinity data suggest that the surface bloom seen in the SeaWiFS data is confined to the shallow (~30m) mixed layer. It is hypothesised that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

  7. The prepared mind. [Serendipitous discovery of demulsifier

    SciTech Connect

    Thompson, N.E.S. )

    1994-09-01

    Products derived from the work of scientists with serendipity, or an imagined faculty for making fluke discoveries by looking for one thing and finding another, include the well-known examples of Teflon, penicillin, X-rays, Velcro, nylon, saccharin, and Nutrasweet. This dream of every scientist came true for the author in the discovery of a dithiocarbamate compound that could be used as a water-clarifying agent for oil fields that produce water. The new agent enables oil companies to discharge water produced in offshore drilling facilities without upsetting the clarity of the aquatic environment. The EPA limit for oil in discharged water is 48 ppm. Failure to maintain this limit will result in shutdown of the platform. The alternative is to pipe the produced water to onshore facilities for treatment before discharge, which costs a good bit more. The serendipitous discovery of the dithiocarbamate compound discussed here as a unique water-clarifying agent has also led to important fundamental advances. The new agent allows producers to use existing water treatment equipment and remain in compliance with the latest limits on oil content. This compound has made it more economical to operate offshore oil and gas production facilities in the Gulf of Mexico and the North Sea.

  8. ChaMP Serendipitous Galaxy Cluster Survey

    SciTech Connect

    Barkhouse, Wayne A.; Green, P.J.; Vikhlinin, A.; Kim, D.-W.; Perley, D.; Cameron, R.; Silverman, J.; Mossman, A.; Burenin, R.; Jannuzi, B.T.; Kim, M.; Smith, M.G.; Smith, R.C.; Tananbaum, H.; Wilkes, B.J.; /Harvard-Smithsonian Ctr. Astrophys. /UC, Berkeley, Astron. Dept. /SLAC /Garching, Max Planck Inst., MPE /Moscow, Space Res. Inst. /NOAO, Tucson /Cerro-Tololo InterAmerican Obs.

    2006-04-03

    We present a survey of serendipitous extended X-ray sources and optical cluster candidates from the Chandra Multi-wavelength Project (ChaMP). Our main goal is to make an unbiased comparison of X-ray and optical cluster detection methods. In 130 archival Chandra pointings covering 13 square degrees, we use a wavelet decomposition technique to detect 55 extended sources, of which 6 are nearby single galaxies. Our X-ray cluster catalog reaches a typical flux limit of about {approx} 10{sup -14} erg s{sup -1} cm{sup -2}, with a median cluster core radius of 21''. For 56 of the 130 X-ray fields, we use the ChaMP's deep NOAO/4m MOSAIC g', r', and i' imaging to independently detect cluster candidates using a Voronoi tessellation and percolation (VTP) method. Red-sequence filtering decreases the galaxy fore/background contamination and provides photometric redshifts to z {approx} 0.7. From the overlapping 6.1 square degree X-ray/optical imaging, we find 115 optical clusters (of which 11% are in the X-ray catalog) and 28 X-ray clusters (of which 46% are in the optical VTP catalog). The median redshift of the 13 X-ray/optical clusters is 0.41, and their median X-ray luminosity (0.5-2 keV) is L{sub X} = (2.65 {+-} 0.19) x 10{sup 43} ergs s{sup -1}. The clusters in our sample that are only detected in our optical data are poorer on average ({approx} 4{sigma}) than the X-ray/optically matched clusters, which may partially explain the difference in the detection fractions.

  9. The BMW-Chandra Serendipitous Source Catalog

    NASA Astrophysics Data System (ADS)

    Romano, P.; Campana, S.; Mignani, R. P.; Moretti, A.; Mottini, M.; Panzera, M. R.; Tagliaferri, G.

    2004-08-01

    We present the BMW-Chandra source catalog drawn from all Chandra ACIS-I pointed observations with an exposure time in excess of 10 ks public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by Lazzati et al. (1999) and Campana et al. (1999), which can characterize point-like as well as extended sources, we identified 21325 sources. Among them, 16758 are serendipitous, i.e. not associated with the targets of the pointings, and do not require a non-automated analysis. This makes our catalog the largest compilation of Chandra sources to date. The 0.5--10 keV absorption corrected fluxes of these sources range from ˜ 3× 10-16 to 9×10-12 erg cm-2 s-1 with a median of 7× 10-15 erg cm-2 s-1. The catalog consists of count rates and relative errors in three energy bands (total, 0.5--7 keV; soft, 0.5--2 keV; and hard band, 2--7 keV), and source positions relative to the highest signal-to-noise detection among the three bands. The wavelet algorithm also provides an estimate of the extension of the source which we refined with a σ -clipping method. We report on the main properties of the sources in our catalog, such as sky coverage ( ˜ 8 deg2 at a limiting flux of ˜ 10-13 erg cm-2 s-1) and cosmological log N--log S for a subset at high Galactic latitude (∣ b ∣ > 20o) for a flux as low as ˜ 1.5 × 10-15 erg cm-2 s-1. Support for this work was provided by the Italian MIUR.

  10. Egg residue considerations during the treatment of backyard poultry.

    PubMed

    Marmulak, Tara; Tell, Lisa A; Gehring, Ronette; Baynes, Ronald E; Vickroy, Thomas W; Riviere, Jim E

    2015-12-15

    The purpose of this digest was to provide US veterinarians guidance on the responsible treatment of backyard poultry flocks. The treatment of backyard poultry can be a daunting task for veterinarians because only limited resources are available; however, it is likely to become an increasingly common task owing to the increasing popularity of backyard poultry throughout the United States, especially in urban and suburban areas. Although backyard poultry flock owners may consider their birds pets, the FDA considers them food-producing animals, and veterinarians should follow all regulations that pertain to food-producing animals when administering or prescribing drugs to those birds. The lack of FDA-approved drugs for use in laying hens frequently necessitates the use of drugs in an extralabel manner in backyard poultry. Unfortunately, information regarding the depletion of drug residues in eggs from hens treated with various drugs in an extralabel manner is sparse or lacking, and veterinarians need to be cognizant of this issue, especially when the eggs from treated hens are intended for human consumption. PMID:26642132

  11. The WWW Cabinet of Curiosities: A Serendipitous Research Tool

    ERIC Educational Resources Information Center

    Arnold, Josie

    2012-01-01

    This paper proposes that the WWW is able to be fruitfully understood as a research tool when we utilise the metaphor of the cabinet of curiosities, the wunderkammer. It unpeels some of the research attributes of the metaphor as it reveals the multiplicity of connectivity on the web that provides serendipitous interactions between unexpected…

  12. 45 CFR 674.7 - Exception for serendipitous finds.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Exception for serendipitous finds. 674.7 Section 674.7 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... meteorite for scientific research purposes, provided that the meteorite is collected in the manner...

  13. 45 CFR 674.7 - Exception for serendipitous finds.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Exception for serendipitous finds. 674.7 Section 674.7 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION... meteorite for scientific research purposes, provided that the meteorite is collected in the manner...

  14. View of walkway between backyards of Buildings No. 12 on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of walkway between backyards of Buildings No. 12 on left and Building No. 10 on right. Building No. 11 at rear. Looking south - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  15. View of walkway between backyards of Buildings No. 10 and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of walkway between backyards of Buildings No. 10 and 12. Building No. 19 at rear. Looking north - Easter Hill Village, Bordered by South Twenty-sixth Street, South Twenty-eighth Street, Hinkley Avenue, Foothill Avenue & Corto Square, Richmond, Contra Costa County, CA

  16. Nature in Your Backyard: Simple Activities for Children.

    ERIC Educational Resources Information Center

    Lang, Susan S.; And Others

    This illustrated book presents the natural world that exists right outside the door through a series of projects, experiments, and activities that are simple enough for young children to do. Activities are divided into six sections: (1) Insects and Worms; (2) Birds; (3) Backyard Animals; (4) Seeds; (5) Plant Magic; and (6) Soil, Air, and Water.…

  17. VIEW FROM THE BACKYARDS OF THE RESIDENCES ON THE SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM THE BACKYARDS OF THE RESIDENCES ON THE SOUTH SIDE OF BIRCH CIRCLE SHOWING CAMP H.M. SMITH RECREATIONAL FACILITIES ON THE LEFT, CLOTHESLINES TO THE RIGHT. VIEW FACING WEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  18. VIEW OF BACKYARD AREA BEHIND FACILITIES 529 (BIRCH CIRCLE) AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF BACKYARD AREA BEHIND FACILITIES 529 (BIRCH CIRCLE) AND 606 (CEDAR DRIVE). VIEW FACING SOUTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  19. The Swift-XRT imaging Performances and Serendipitous Survey

    NASA Technical Reports Server (NTRS)

    Moretti, A.; Perri, M.; Capalbi, M.; Abbey, A.F.; Angelini, L.; Beardmore, A.; Burrows, D.N.; Campana, S.; Chincaini, G.; Citterio, O.; Cusumano, G.; Evans, P.A.; Giommi, P.; Godet, O.; Guidorzi, C.; Grupe, D.; Hill, J.E.; Kennea, J.A.; La Parola, V.; Mangano, V.; Mineo, T.; Morris, D.C.; Nousek, J.A.; Osborne, J.P.; Page, K.L.

    2007-01-01

    We are exploiting thc Swift X-ray Telescope (XRT) deepest GR.B follow-up observations to study the cosmic X-Ray Background (XRB) population in the 0.2-10 keV energy band. We present some preliminary results of a serendipitous survey performed on 221 fields observed with exposure longer than 10 ks. We show that the XRT is a profitable instrument for surveys and that it is particularly suitable for the search and observation of ext,ended objects like clusters of galaxies. We used the brightest serendipitous sources and the longest observations to test. the XRT optics performance and the background characteristics all over the field of view, in different energy bands during the first 2.5 years of fully operational missions.

  20. Serendipitous Offline Learning in a Neuromorphic Robot

    PubMed Central

    Stewart, Terrence C.; Kleinhans, Ashley; Mundy, Andrew; Conradt, Jörg

    2016-01-01

    We demonstrate a hybrid neuromorphic learning paradigm that learns complex sensorimotor mappings based on a small set of hard-coded reflex behaviors. A mobile robot is first controlled by a basic set of reflexive hand-designed behaviors. All sensor data is provided via a spike-based silicon retina camera (eDVS), and all control is implemented via spiking neurons simulated on neuromorphic hardware (SpiNNaker). Given this control system, the robot is capable of simple obstacle avoidance and random exploration. To train the robot to perform more complex tasks, we observe the robot and find instances where the robot accidentally performs the desired action. Data recorded from the robot during these times is then used to update the neural control system, increasing the likelihood of the robot performing that task in the future, given a similar sensor state. As an example application of this general-purpose method of training, we demonstrate the robot learning to respond to novel sensory stimuli (a mirror) by turning right if it is present at an intersection, and otherwise turning left. In general, this system can learn arbitrary relations between sensory input and motor behavior. PMID:26913002

  1. Serendipitous Offline Learning in a Neuromorphic Robot.

    PubMed

    Stewart, Terrence C; Kleinhans, Ashley; Mundy, Andrew; Conradt, Jörg

    2016-01-01

    We demonstrate a hybrid neuromorphic learning paradigm that learns complex sensorimotor mappings based on a small set of hard-coded reflex behaviors. A mobile robot is first controlled by a basic set of reflexive hand-designed behaviors. All sensor data is provided via a spike-based silicon retina camera (eDVS), and all control is implemented via spiking neurons simulated on neuromorphic hardware (SpiNNaker). Given this control system, the robot is capable of simple obstacle avoidance and random exploration. To train the robot to perform more complex tasks, we observe the robot and find instances where the robot accidentally performs the desired action. Data recorded from the robot during these times is then used to update the neural control system, increasing the likelihood of the robot performing that task in the future, given a similar sensor state. As an example application of this general-purpose method of training, we demonstrate the robot learning to respond to novel sensory stimuli (a mirror) by turning right if it is present at an intersection, and otherwise turning left. In general, this system can learn arbitrary relations between sensory input and motor behavior. PMID:26913002

  2. The XMM-Newton serendipitous ultraviolet source survey catalogue

    NASA Astrophysics Data System (ADS)

    Page, M. J.; Brindle, C.; Talavera, A.; Still, M.; Rosen, S. R.; Yershov, V. N.; Ziaeepour, H.; Mason, K. O.; Cropper, M. S.; Breeveld, A. A.; Loiseau, N.; Mignani, R.; Smith, A.; Murdin, P.

    2012-10-01

    The XMM-Newton Serendipitous Ultraviolet Source Survey (XMM-SUSS) is a catalogue of ultraviolet (UV) sources detected serendipitously by the Optical Monitor (XMM-OM) on board the XMM-Newton observatory. The catalogue contains UV-detected sources collected from 2417 XMM-OM observations in one to six broad-band UV and optical filters, made between 2000 February 24 and 2007 March 29. The primary contents of the catalogue are source positions, magnitudes and fluxes in one to six passbands, and these are accompanied by profile diagnostics and variability statistics. XMM-SUSS is populated by 753 578 UV source detections above a 3σ signal-to-noise ratio threshold limit which relate to 624 049 unique objects. Taking account of substantial overlaps between observations, the net sky area covered is 29-54 deg2, depending on UV filter. The magnitude distributions peak at mAB = 20.2, 20.9 and 21.2 in UVW2 (λeff = 2120 Å), UVM2 (λeff = 2310 Å) and UVW1 (λeff = 2910 Å), respectively. More than 10 per cent of the sources have been visited more than once using the same filter during XMM-Newton operation, and >20 per cent of sources are observed more than once per filter during an individual visit. Consequently, the scope for science based on temporal source variability on time-scales of hours to years is broad. By comparison with other astrophysical catalogues we test the accuracy of the source measurements and define the nature of the serendipitous UV XMM-OM source sample. The distributions of source colours in the UV and optical filters are shown together with the expected loci of stars and galaxies, and indicate that sources which are detected in multiple UV bands are predominantly star-forming galaxies and stars of type G or earlier.

  3. Lead exposure from backyard chicken eggs: a public health risk?

    PubMed

    Bautista, Adrienne C; Puschner, Birgit; Poppenga, Robert H

    2014-09-01

    Although the USA has made significant strides in reducing lead exposure, new and emerging sources are raising cause for public concern. Recent reports of finding lead in eggs from chickens raised in urban gardens has highlighted the need to consider the potential health risks of consuming eggs from backyard chickens. Following the detection of 0.33 μg/g lead in the edible portion of eggs submitted for lead analysis from a backyard chicken owner, further investigation was conducted to determine the source and extent of lead exposure in the flock. Several birds, almost two dozen eggs, and environmental samples were submitted to the California Animal Health and Food Safety Laboratory for further testing. Lead was detected in the blood, liver, kidney, and bone at varying concentrations in all birds but was not detected in the muscle tissue. All egg shells contained detectable amounts of lead, while only a little over half of the edible portion of the eggs contained lead. The detected concentrations in the edible portion approached or exceeded the recommended threshold of lead consumption per day that should not be exceeded by young children if a child consumed one average-sized egg. Peeling paint from a wooded structure adjacent to the flock's coop was the likely lead source containing 3,700 μg/g lead. Thus, removal of the chickens from the source and periodic testing of eggs for lead were recommended. This case illustrates the need for consumers and health care workers to be aware of potential sources for lead exposure such as backyard chickens. PMID:24943230

  4. Prevalence and differentiation of diseases in Maryland backyard flocks.

    PubMed

    Madsen, Jennifer M; Zimmermann, Nickolas G; Timmons, Jennifer; Tablante, Nathaniel L

    2013-09-01

    Several epidemiologic surveillance studies have implicated backyard flocks as a reservoir for poultry diseases; however, much debate still exists over the risk these small flocks pose. To evaluate this concern, the prevalence of Newcastle disease (ND), infectious laryngotracheitis (ILT), Mycoplasma gallisepticum (MG), and Salmonella was determined in 39 Maryland backyard flocks. Serum, tracheal, and cloacal swabs were randomly collected from 262 birds throughout nine counties in Maryland. Through PCR and ELISA analysis, disease prevalence and seroprevalence were determined in flocks, respectively, for the following: ND (0%, 23%); ILT (26%, 77%); MG (3%, 13%); and Salmonella (0%, not done). Vaccine status could not be accurately confirmed. Premise positives were further differentiated and identified by partial nucleotide sequencing. Screening of the 10 ILT premise positives showed that most were live attenuated vaccines: eight matched a tissue culture origin vaccine, one matched a chicken embryo origin (CEO) vaccine, and one was CEO related. The single MG-positive flock, also positive for the CEO-related sequence, was identified as the infectious S6 strain. The prevalence rates for these economically important poultry diseases ranged from none to relatively low, with the vast majority of sampled flocks presenting no clinical signs. PMID:24283123

  5. IRAS serendipitous survey observations of Pluto and Charon

    NASA Technical Reports Server (NTRS)

    Sykes, Mark V.; Cutri, Roc M.; Lebofsky, Larry A.; Binzel, Richard P.

    1987-01-01

    On Aug. 16, 1983, the Infrared Astronomical Satellite made two separate pointed observations of Pluto and its moon Charon. Because of the small angular displacement of the system between the times of measurement, the Pluto-Charon system was identified as a source in the Serendipitous Survey (SSC 14029+0518). Detections were made at 60 and 100 micrometers with color-corrected flux densities of 581 + or - 58 and 721 + or - 123 millijanskys, respectively. Pluto is best described as having a dark equatorial band, and brighter polar caps of methane ice extending to + or - 45 deg latitude, at most. An upper limit of approximately 9 meter-amagats is placed on the column abundance of a methane atmosphere on Pluto, which is comparable to recent upper limits based on independent ground-based spectroscopy.

  6. Campylobacter infections in children exposed to infected backyard poultry in Egypt.

    PubMed

    El-Tras, W F; Holt, H R; Tayel, A A; El-Kady, N N

    2015-01-01

    Campylobacteriosis is a zoonotic disease which has a worldwide public health impact. The disease is endemic in Egypt; however, the epidemiology in animals and humans has not been fully characterized. The objective of this study was to compare the risk of Campylobacter faecal carriage in children exposed to Campylobacter-infected vs. non-infected backyard poultry and to identify risk factors for a backyard being classified as infected. A total of 103 households which owned backyard poultry were sampled from a rural community in Egypt. Within these households 379 poultry and 106 children were tested for C. jejuni and C. coli; 23·5% and 5·5% of poultry were positive for C. jejuni and C. coli, respectively. In the studied households; 12·3% of children were positive for C. jejuni, and 2·8% were positive for C. coli. Using logistic regression, households with poultry positive for C. jejuni had 3·86 (95% confidence interval 1·0-15·0) times the odds of having children positive for C. jejuni compared to those housed with poultry which all tested negative. Backyard poultry may present a transmission route of C. jejuni to children. Backyards with poor cleaning and disinfection, wet litter and manure disposed of within the backyard had increased odds of being positive for C. jejuni. Enhancing biosecurity and management in poultry backyards may reduce the risk of the disease. PMID:24774694

  7. Raising chickens in city backyards: the public health role.

    PubMed

    Pollock, S L; Stephen, C; Skuridina, N; Kosatsky, T

    2012-06-01

    There is increasing interest in raising chickens in urban settings across North America. Current regulations on backyard chickens vary by jurisdiction due to concerns about perceived health threats. Proposed negative impacts on public health and community well-being include infectious diseases acquired through rearing practices or consumption of eggs, inappropriate waste management, interaction with pests and predators and nuisance factors such as noise and odour. Proposed benefits are derived largely from the human-animal bond and from feelings of autonomy over food selection. The importance or validity of claims of positive and negative effects cannot be supported by literature specific to the urban agriculture context. Public health practitioners might approach this issue in a manner analogous to concerns over keeping domestic pets. PMID:22083301

  8. The Calar Alto Serendipitous Asteroid Discovery and Observation program --- CASADO

    NASA Astrophysics Data System (ADS)

    Hellmich, S.; Debschütz, L.; Hafemeister, L.; Gerull, O.; Proffe, G.; Mottola, S.; Hahn, G.

    2014-07-01

    In the past years much effort was put into programs for asteroid discovery. Large-scale programs like LINEAR[1] and Catalina Sky Survey were introduced and powerful telescopes like Pan-STARRS[3] were built only for the purpose of finding asteroids, to name just a few. Thus, the rate of asteroid discoveries literally exploded. Although by far the largest number of observations is done by the big surveys also smaller observation programs can provide valuable data. Telescopes, whether they hunt asteroids or do other tasks, image them all the time. By searching the images for serendipitously observed asteroids one can contribute to refine orbits of already known asteroids, find new objects and sometimes even determine basic physical properties which are unknown for most of the known asteroids. In October 2012 we started CASADO, a program for secondary usage of the data collected within a long term observation program carried out at the 1.23m telescope at Calar Alto. The telescope is equipped with a 4k by 4k CCD covering a field of view of about 22 by 22 arcmin. We use the telescope for 100 nights per year mainly for photometric observations of Jupiter Trojans[4] but also main-belt objects, satellites of Jupiter and comets are sometimes observed. In a typical observation campaign, we focus on about 15 to 20 minor bodies of which we repetitively observe 10 to 15 during a single night. To search the fields for serendipitously-observed objects we implemented a semi-automated software which performs the astrometric calibration, searches the images for moving objects, identifies already known asteroids and prepares MPC reports. By calculating preliminary orbital elements for the newly-discovered objects using OpenOrb[2] we are also able to compute ephemeris and reliably link the observations of these objects over multiple nights. Not only do we process the images of ongoing campaigns, but also went back in time to July 2011. While the astrometry of the objects which have

  9. Serendipitous Observations of Asteroids by the K2 Mission

    NASA Astrophysics Data System (ADS)

    Barentsen, Geert

    2015-11-01

    The K2 mission is using the unique assets of the Kepler space telescope to perform long-baseline, high-cadence, high-precision photometry of targets selected by the community. Unlike the original Kepler mission, the loss of two reaction wheels requires K2 to point near the ecliptic plane. As a result, thousands of faint asteroids can be seen to pass through the target pixel masks that are downlinked to earth after each ~75-day observing campaign. I will show how these serendipitous observations of asteroids can be used to obtain lightcurves for faint (V>18) objects which are otherwise challenging to target from the ground. In particular, I will demonstrate that the data are well-suited to identify small asteroids with rotation periods near or below the ~2 hour "spin barrier". I will also highlight the K2 data of other solar system bodies, including the comets, trans-Neptunian objects and Jupiter trojans for which dedicated pixel masks have been (or will be) downlinked. Owing to its ecliptic pointing and 1.4-meter diameter mirror, K2 is offering unique time-series photometry of small solar system bodies at a precision which is unlikely to be rivaled by the future, smaller-aperture photometric missions such as TESS and PLATO.

  10. Shaken, not stirred: a serendipitous study of ants and earthquakes.

    PubMed

    Lighton, John R B; Duncan, Frances D

    2005-08-01

    There is anecdotal evidence for profound behavioral changes prior to and during earthquakes in many organisms, including arthropods such as ants. Behavioral or physiological analysis has often, in light of these reports, been proposed as a means of earthquake prediction. We report here a serendipitous study of the effect of the powerful Landers earthquake in the Mojave Desert, USA (Richter magnitude 7.4) on ant trail dynamics and aerobic catabolism in the desert harvester ant Messor pergandei. We monitored trail traffic rates to and from the colony, trail speed, worker mass distributions, rates of aerobic catabolism and temperature at ant height before and during the earthquake, and for 3 days after the earthquake. Contrary to anecdotal reports of earthquake effects on ant behavior, the Landers earthquake had no effect on any measured aspect of the physiology or behavior of M. pergandei. We conclude that anecdotal accounts of the effects of earthquakes or their precursors on insect behavior should be interpreted with caution. PMID:16081608

  11. The BMW-Chandra survey. Serendipitous Source Catalogue

    NASA Astrophysics Data System (ADS)

    Romano, P.; Mignani, R. P.; Campana, S.; Moretti, A.; Panzera, M. R.; Tagliaferri, G.; Mottini, M.

    2009-07-01

    We present the BMW-Chandra source catalogue derived from Chandra ACIS-I observations (exposure time > 10ks) public as of March 2003 by using a wavelet detection algorithm (Lazzati et al. 1999; Campana et al. 1999). The catalogue contains a total of 21325 sources, 16758 of which are serendipitous. Our sky coverage in the soft band (0.5-2keV, S/N=3) is ~ 8 deg2 for FX ≥ 10-13 erg cm-2 s-1, and ~ 2 deg2 for FX ≥ 10-15 erg cm-2 s-1. The catalogue contains information on positions, count rates (and errors) in three energy bands (total, 0.5-7keV; soft, 0.5-2keV; and hard, 2-7keV), and in four additional energy bands, SB1 (0.5-1keV), SB2 (1-2keV), HB1 (2-4keV), and HB2 (4-7keV), as well as information on the source extension, and cross-matches with the FIRST, IRAS, 2MASS, and GSC-2 catalogues.

  12. Serendipitous results of a pilot study: precaution indicated.

    PubMed

    Heifetz, S B; Proskin, H M

    1995-01-01

    A pilot study was conducted to estimate sample size for a clinical trial in a F area. In 1992, 98 children 14 years of age living in Fall River, MA were examined for dental caries: Fall River was fluoridated in 1973. Residence histories showed that 74% lived there from birth (B), 12% were residents from kindergarten or 1st grade (K1) and 14% moved into the community at a later time (LT). Findings on caries prevalence showed an inverse relation between DMFS and initial age of residence; mean DMFS was 3.00 for Group B, 5.33 for Group K1 and 6.93 for Group LT. A one-way ANOVA indicated significant differences among the groups (p=0.05). Because residence from birth or from early life can be considered a proxy for systemic fluoride exposure, and because controversy currently surrounds the issue of topical versus systemic benefits in explaining the mechanism of action of fluoride, the results appeared to have importance. However, internal analyses of the data comparing surface-specific (pit and fissure) results among the groups for early erupting teeth with varying systemic exposure to fluoridated water and for late erupting teeth, all with appreciable systemic exposure, showed comparable relative differences in DMFS scores. Lack of internal validity, therefore, discounted a conclusion from overall results of the role of systemic fluorides in providing decay preventive benefits. If there is any conclusion that can be drawn it is that serendipitous escapades with data from a pilot study, if not rigorously analyzed and cautiously interpreted, tend to further muddy the waters (fluoridated in this case) on controversial issues and should best be avoided. PMID:8694985

  13. Not in whose backyard Minority population concentrations and noxious facility sites

    SciTech Connect

    Nieves, L.A.

    1992-01-01

    The NIMBY (not in may backyard) syndrome has become the nemesis of facility siting efforts in the USA. Given people's reluctance to live near noxious facilities, in whose backyard are such facilities located This study employs US county-level data to examine relative concentrations of minorities living near noxious facilities. Facility types analyzed include electric generating plants, manufacturing plants, Superfund sites, and radioactive waste disposal sites. While this study does not address which cam first, the minority population concentration or the noxious facilities, it documents their current degree of association.

  14. Not in whose backyard? Minority population concentrations and noxious facility sites

    SciTech Connect

    Nieves, L.A.

    1992-04-01

    The NIMBY (not in may backyard) syndrome has become the nemesis of facility siting efforts in the USA. Given people`s reluctance to live near noxious facilities, in whose backyard are such facilities located? This study employs US county-level data to examine relative concentrations of minorities living near noxious facilities. Facility types analyzed include electric generating plants, manufacturing plants, Superfund sites, and radioactive waste disposal sites. While this study does not address which cam first, the minority population concentration or the noxious facilities, it documents their current degree of association.

  15. An Examination of the NIMBY Syndrome: Why Not in My Backyard?

    ERIC Educational Resources Information Center

    Halstead, John M.; And Others

    1993-01-01

    According to 308 responses from households in 3 New Hampshire towns, those who held "Not in My Backyard" (NIMBY) beliefs about waste management facilities were primarily motivated by child health concerns. Those willing to host a recycling center or who believed recycling was a fad were less likely to have NIMBY attitudes. (SK)

  16. Science Is for the Birds: Promoting Standards-Based Learning through Backyard Birdwatching.

    ERIC Educational Resources Information Center

    Coverdale, Gregory A.

    2003-01-01

    Explains forest fragmentation, the destruction of physical habitats for animals such as birds and points out the importance of studies on habitat and biodiversity. Introduces project ideas for songbird populations and their habitats which can be conducted in backyards or schoolyards. (YDS)

  17. Risk factors for infectious diseases in backyard poultry farms in the Poyang Lake area, China.

    PubMed

    Wang, Yong; Jiang, Zhiben; Jin, Zhenyu; Tan, Hua; Xu, Bing

    2013-01-01

    Emergence and transmission of infectious diseases have an enormous impact on the poultry industry and present a serious threat to the health of humans and wild birds. Noncommercial poultry operations, such as backyard poultry facilities in China, are potential sources of virus exchange between commercial poultry and wild birds. It is particularly critical in wetland areas where backyard poultry have close contact with commercial poultry and migratory birds, therefore increasing the risk of contracting infectious diseases. To evaluate the transmission risks, a cross-sectional study was undertaken in the Poyang Lake area, China, involving 309 residents in the backyard poultry farms in three counties (Region A, B, and C) of Jiangxi Province. We examined the backyard poultry population, poultry species, presence of poultry deaths from infectious diseases, food sources, and biosecurity practices. Region B ranked highest for biosecurity while region C ranked lowest. The risks of infectious diseases were assessed by adjusted odds ratio based on multivariate logistic regression analysis. Potential risk factors in the three regions of the study site were compared. In Region A, significant factor was contact of poultry with wild birds (OR: 6.573, 95% CI: 2.148-20.115, P=0.001). In Region B, the most significant factor was contact of poultry with neighboring backyard waterfowls (OR: 3.967, 95% CI: 1.555-10.122, P=0.004). In Region C, significant factors were poultry purchase from local live bird markets (OR: 3.740, 95% CI: 1.243-11.255, P=0.019), and contact of poultry with wild birds (OR: 3.379, 95% CI: 1.058-10.791, P=0.040). In summary, backyard poultry was significantly affected by neighboring commercial poultry and close contact with wild birds. The results are expected to improve our understanding of the transmission risks of infectious diseases in a typical backyard poultry environment in rural China, and address the need to improve local farming practices and take

  18. How backyard poultry flocks influence the effort required to curtail avian influenza epidemics in commercial poultry flocks

    PubMed Central

    Smith, G.; Dunipace, S.

    2011-01-01

    This paper summarizes the evidence that the contribution of backyard poultry flocks to the on-going transmission dynamics of an avian influenza epidemic in commercial flocks is modest at best. Nevertheless, while disease control strategies need not involve the backyard flocks, an analysis of the contribution of each element of the next generation matrix to the basic reproduction number indicates that models which ignores the contribution of backyard flocks in estimating the effort required of strategies focused one host type (eg commercial flocks only) necessarily underestimate the level of effort to an extent that may matter to policy makers. PMID:21624777

  19. Search for serendipitous Oort cloud object occultation in X-rays

    NASA Astrophysics Data System (ADS)

    Shang, Jie-Rou; Liu, Chih-Yuan; Chang, Hsiang-Kuang

    2015-08-01

    Serendipitous occultation search is a way to study small objects in the outer Solar system like trans-Neptunian objects (TNOs) by extracting and analyzing the diffraction pattern in the occultation lights. There are already some reported detections in both optical and X-ray bands in this kind of search. Except for KBOs, this method also has the potential to extend the search to a distance as far away as the Oort cloud region (beyond a few thousands AU). As the distance is larger, a shorter wavelength is needed to have a smaller Fresnel scale, with which occultation may be more easily detected. Here we introduce the serendipitous occultation method we used in searching Oort cloud objects occultation, and present the results of using Rossi X-ray Timing Explorer/Proportional Counter Array data of Sco X-1 taken from 1996 February to 2012 January.

  20. Search for serendipitous Oort cloud object occultation in X-rays

    NASA Astrophysics Data System (ADS)

    Shang, J.-R.; Liu, C.-Y.; Chang, H.-K.; Chen, K.-T.

    2015-10-01

    The existence of Oort cloud objects remains a hypothesis since proposed more than half a century ago. Here we report the results of search for serendipitous occultation events caused by Oort Cloud Objects (OCOs) using Rossi X-ray Timing Explorer/Proportional Counter Array (RXTE/PCA) data of Sco X-1 taken from 1996 February to 2012 January. We also investigate the dependence of detection efficiency on OCO size to better define the sensible size range of our approach.

  1. The development of a model for artificial insemination by backyard pig farmers in Thailand.

    PubMed

    Visalvethaya, Weethima; Tantasuparuk, Wichai; Techakumphu, Mongkol

    2011-04-01

    The aim of this study was to develop and evaluate a model of artificial insemination (AI) technology transferable to backyard pig farmers for strengthening pig productivity in rural areas in Thailand. An AI center, criteria and process for farmer selection, an AI training program, AI practice in pigs, and a backyard farmer network were created as a model. Five hundred and thirty-one farrowing records from 307 sows were analyzed. Farrowing rates (FR), total number of piglets born (TB), and number of piglets born alive (BA) were studied. AI has led to better results in FR, TB, and BA than natural mating (P < 0.05). Demographic factors such as sex and age of farmers only had significant effects on FR (P < 0.05), while educational levels and farmers' AI experience had significant effects on TB and BA (P < 0.05). Model factors such as type of training, semen delivery systems, and semen storage time did not have significant effects on FR, TB, and BA. In conclusion, using this model, we found that backyard farmers could be trained in AI techniques in order to achieve equally good results as experienced technicians. Male farmers within working age or older, with a high school education or higher are the recommended target groups for implementing this model. Strong cooperation with clear responsibilities of all stakeholders could create a good network of backyard pig farmers. Therefore, the implementation of AI techniques in pig production can be applied to the target group with an aim towards a sustainable, self-sufficient community. PMID:21174229

  2. Prevalence and some risk factors associated with trichinellosis in backyard pig farms in Zaria, Nigeria.

    PubMed

    Momoh, Halimat Asabe; Bello, Mohammed; Inabo, Helen; Wada, Yusuf; Adole, Enechojo Bernadette; Madaiki, Blessed Dauda; Aregbe, Elizabeth Adenike

    2013-06-01

    The aim of this study was to determine the presence of trichinellosis in backyard-farmed pigs and the risk factors associated with the infection in Zaria, Kaduna State. Serum samples were collected from 120 pigs selected at random from 50 small backyard farms, and the presence of Trichinella spp. antibodies was determined using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. Data on farm management practices from the farms were obtained through the use of a structured questionnaire. The overall seroprevalence of Trichinella spp.-specific antibodies was 40 % (48/120) by ELISA. All the extensive farms sampled had at least one Trichinella-positive animal. The age and sex of the animals were not significantly (p>0.05) associated with the infection; however, the management systems, presence of rodents, rodent control, and access to dead pigs showed significant (p<0.05) association with Trichinella spp.-infected pigs on the farm. In conclusion, there was a high prevalence of antibodies to trichinellosis in backyard raised pigs in Zaria, and intensive pig farming with the adoption of proper biosecurity measures is advocated to prevent the transmission and spread of trichinellosis. PMID:23264057

  3. Prospects of improved classical swine fever control in backyard pigs through oral vaccination.

    PubMed

    Dietze, Klaas; Milicevic, Vesna; Depner, Klaus

    2013-01-01

    Success in controlling classical swine fever (CSF) in regions with high proportions of pigs kept in small scale and low-biosecurity production systems, often referred to as backyard production, tends to be hampered by the lack of control strategies properly addressing the peculiarities of this epidemiologically important subpopulation. Under many circumstances the commonly practiced parenteral immunisation using live attenuated C-strain vaccine shows limitations concerning outreach of services and overall vaccination coverage in the backyard pig population. It is therefore proposed to stronger consider oral vaccine baits, as used for CSF control in wild boar, to complement the set of tools for CSF control in domestic pigs. First field results confirm the feasibility of its practical implementation. Next to the increased flexibility in the delivery to the end user, this non-invasive method comes along with the advantage of reducing the need for direct animal contact and biosecurity-relevant interventions that might cause the spread of diseases through vaccination campaigns entailing external personnel entering farm premises. In combination with epidemiological methods suitable for this production sector like e.g. participatory epidemiology, adapted CSF control strategies can better support the needs of small scale farmers and ultimately contribute to household food security for a large number of stakeholders that will have backyard pig production as a reality for decades to come. PMID:24511822

  4. Backyard chicken flocks pose a disease risk for neotropic birds in Costa Rica.

    PubMed

    Hernandez-Divers, Sonia M; Villegas, Pedro; Jimenez, Carlos; Hernandez-Divers, Stephen J; Garcia, Maricarmen; Riblet, Sylva M; Carroll, C Ron; O'Connor, Barry M; Webb, Julie L; Yabsley, Michael J; Williams, Susan M; Sanchez, Susan

    2008-12-01

    Pathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the United States, as well as potential economic losses for resource-poor farmers. Free-roaming backyard chickens are commonly kept in shade-grown coffee plantations, habitats that attract large numbers of wild birds. The husbandry and pathogen prevalence of backyard chicken flocks in San Luis, Costa Rica, were investigated. Based on serologic evidence, Newcastle disease virus, infectious laryngotracheitis virus, infectious bronchitis virus, chicken anemia virus, and infectious bursal disease virus, as well as both Mycoplasma gallisepticum and Mycoplasma synoviae, appear to be significant diseases of this population, and thus, we consider these backyard chickens potential reservoirs for these diseases. There was no evidence of avian influenza. Interviews, clinical examinations, and microscopic examination of tissues led us to believe that poxvirus is also a significant cause of morbidity and mortality in these chickens. We found that Escherichia coli isolates were resistant against tilmicosin, tetracycline, ampicillin, amoxicillin with clavulanic acid, ticarcillin, and cephalothin, and contained genes considered responsible for conferring tetracycline resistance. Additionally, although production was not measured, we suspect that husbandry and lack of preventative medicine are directly related to the diseases reported, all of which negatively affect production. PMID:19166045

  5. Avian influenza H5N1 virus infections in vaccinated commercial and backyard poultry in Egypt.

    PubMed

    Hafez, M H; Arafa, A; Abdelwhab, E M; Selim, A; Khoulosy, S G; Hassan, M K; Aly, M M

    2010-08-01

    In this paper, we describe results from a high-pathogenic H5N1 avian influenza virus (AIV) surveillance program in previously H5-vaccinated commercial and family-backyard poultry flocks that was conducted from 2007 to 2008 by the Egyptian National Laboratory for Veterinary Quality Control on Poultry Production. The real-time reverse transcription PCR assay was used to detect the influenza A virus matrix gene and detection of the H5 and N1 subtypes was accomplished using a commercially available kit real-time reverse transcription PCR assay. The virus was detected in 35/3,610 (0.97%) and 27/8,682 (0.31%) of examined commercial poultry farms and 246/816 (30%) and 89/1,723 (5.2%) of backyard flocks in 2007 and 2008, respectively. Positive flocks were identified throughout the year, with the highest frequencies occurring during the winter months. Anti-H5 serum antibody titers in selected commercial poultry ranged from <2 (negative) to 9.6 log(2) when determined in the hemagglutination inhibition test using a H5 AIV antigen. In conclusion, despite the nationwide vaccination strategy of poultry in Egypt to combat H5N1 AIV, continuous circulation of the virus in vaccinated commercial and backyard poultry was reported and the efficacy of the vaccination using a challenge model with the current circulating field virus should be revised. PMID:20634514

  6. Sero-survey of Avian Influenza in backyard poultry and wild bird species in Iran-2014.

    PubMed

    Fallah Mehrabadi, M H; Bahonar, A R; Vasfi Marandi, M; Sadrzadeh, A; Tehrani, F; Salman, M D

    2016-06-01

    In almost all villages in Iran backyard birds, especially chickens, are kept for egg and meat production. AI H9N2 subtype is endemic in Iran. Therefore, estimation of AI prevalence among these birds is important to determine the risk of transmission of infection to commercial farms. The aim of this study was to estimate subclinical infections or previous exposure to H5, H7, and H9 subtypes and to identify potentially important determinants of prevalence of this infectious at premises level in backyard poultry, bird gardens, zoos, and wild bird markets in Iran. A survey was conducted using a cross-sectional design throughout the entire country. A total of 329 villages, seven bird gardens, three zoos and five wild bird markets were included. In each village four families that kept birds were included in the collection of biological samples and background information. The Enzyme-Linked Immunosorbent Assay (ELISA) was used as the screening test and all ELISA-positive samples were examined with the HI test to differentiate H5, H7, and H9. Among the bird gardens, eight of 15 premises (53.3%) were positive in both the ELISA test and HI for H9N2. Testing of samples collected in the villages revealed that 296 out of 329 villages (90%) had positive ELISA tests and also HI tests for H9. The HI-H9 mean titers in positive units were significantly higher than negative units (P<.001). This study revealed no significant statistical differences between risk variables in seropositive and seronegative bird gardens in the case of H9 (P>.05). The results of this study showed that among the risk variables, mountainous area was a protective factor and lack of hygienic disposal of dead birds was a risk factor for AI; this was also observed in rural poultry. The high sero-prevalence of influenza H9N2 in rural domestic poultry indicates that the disease is endemic. It is necessary to include backyard poultry in any surveillance system and control strategy due to the existence of AIV in

  7. VizieR Online Data Catalog: Swift/UVOT Serendipitous Source Catalog (Yershov, 2015)

    NASA Astrophysics Data System (ADS)

    Yershov, V. N.

    2015-11-01

    The first version of the Swift UVOT serendipitous source catalogue (UVOTSSC) provides positions and magnitudes, as well as errors and upper limits of confirmed sources for observations taken from start of operations in 2005 until October 1st of 2010. The first version of the Swift UVOT Serendipitous Source Catalogue (UVOTSSC) has been produced by processing the image data obtained from the Swift Ultraviolet and Optical Telescope (UVOT) from the beginning of the mission (2005) until 1st of October of 2010. The data processing was performed at the Mullard Space Science Laboratory (MSSL, University College London, U.K.) using Swift FTOOLS from NASA's High Energy Astrophysics Software (HEASoft-6.11), with some customising of the UVOT packages in order to get more complete source detection and properly apply quality flags to those sources that were detected within the UVOT image artefacts. The total number of observations with 17'x17' images used for version 1 of the catalogue is 23,059, giving 6,200,016 sources in total, of which 2,027,265 have multiple entries in the source table because they have been detected in more than one observation. Some sources were only observed in one filter. The total number of entries in the source table is 13,860,568. The S/N ratio for all sources exceeds 5 for at least one UVOT filter, the rest of the filters having a S/N greater than 3. (3 data files).

  8. Serendipitous Chandra X-ray Spectroscopy of GALEX Nearby Young-Star Survey (GALNYSS) Candidates

    NASA Astrophysics Data System (ADS)

    Kastner, Joel H.; Baum, N.; Principe, D.; Rodriguez, D.

    2014-01-01

    More than 2000 candidate young (age 10-100 Myr) low-mass stars within ~100 pc of Earth have been identified by the Galex Nearby Young-Star Survey (GALNYSS), via the combination of ultraviolet (Galex) and near-IR (WISE and 2MASS) photometry and kinematic data. Among these candidates, we find more than a dozen objects for which serendipitous archival Chandra X-ray observations are available. The spectral types for these objects, if stellar, range from early- to mid-M. Hence, this serendipitously observed subsample affords the opportunity to study the X-ray emission characteristics of young stars at the low-mass end of the stellar mass spectrum. We present preliminary results of spectral analysis, including estimates of plasma temperature, intervening absorption, and intrinsic X-ray luminosities, for these Chandra X-ray counterparts to GALNYSS candidates. These results will be used both to confirm young, late-type star status and to investigate the evolution of magnetic (coronal) activity in stars whose masses potentially range from a few tenths of a solar mass down to near the H-burning limit. This work is supported by NASA Astrophysics Data Analysis Program award NNX12AH37G to RIT and UCLA and Chilean FONDECYT grant 3130520 to Universidad de Chile.

  9. Squamous Cell Carcinoma of the Oropharynx and Esophagus with Pulmonary Metastasis in a Backyard Laying Hen.

    PubMed

    Laura, Nordio; Marta, Vascellari; Giacomo, Berto; Luca, Bano

    2016-09-01

    A backyard laying hen exhibiting muscular atrophy, dyspnea, and absence of egg production was analyzed for diagnostic insights. Gross findings revealed the presence of a large ulcerated mass with irregular edges involving the caudal part of the oropharynx and the cranial part of the esophagus, occluding the lumen of the esophagus and compressing the trachea. Small nodular lesions were detected also in the lungs. Histologically, both esophageal and pulmonary masses were characterized by nests of pleomorphic epithelial cells with squamous differentiation. The diagnosis was of squamous cell carcinoma of the esophagus with the uncommon feature of pulmonary metastasis. PMID:27610733

  10. Backyard chickens in the United States: a survey of flock owners.

    PubMed

    Elkhoraibi, C; Blatchford, R A; Pitesky, M E; Mench, J A

    2014-11-01

    Although it has become increasingly popular to keep backyard chickens in the United States, few studies have provided information about these flocks. An online survey of backyard chicken owners was conducted, advertised through Master Gardeners' websites, social platforms, and other sites. The survey had 56 questions about flock history, husbandry, health care, and owner attitudes and demographics. Surveys received (n = 1,487) came almost equally from urban, suburban, and rural areas. Most (71%) respondents owned fewer than 10 chickens and had kept chickens for less than 5 yr (70%). Major reasons for keeping chickens were as food for home use (95%), gardening partners (63%), pets (57%), or a combination of these. Rural respondents had larger flocks (P ≤ 0.001) and were more likely to keep chickens as a source of income or for show (P ≤ 0.001) than urban and suburban respondents. Owners thought that eggs/meat from their chickens were more nutritious (86%), safer to consume (84%), and tasted better (95%) than store-bought products, and also that the health and welfare of their chickens was better (95%) than on commercial farms. The majority (59%) indicated no flock health problems in the last 12 mo. However, there was a lack of awareness about some poultry health conditions. Many knew either little or nothing about exotic Newcastle or Marek's disease, and most (61%) did not vaccinate against Marek's. Respondents wanted to learn more about various flock management topics, especially how to detect (64%) and treat (66%) health problems. The Internet was the main source of information (87%) used by backyard flock owners, followed by books/magazines (62%) and feed stores (40%). Minimizing predation was the most cited challenge (49%), followed by providing adequate feed at low cost (28%), dealing with soil management (25%), and complying with zoning regulations (23%). The evidence obtained from this survey will help to determine what information and resources are

  11. Observations of basic diagnostic profile patterns seen in some common disorders of backyard poultry species.

    PubMed

    Speer, B L

    1999-09-01

    Poultry species--chickens, ducks, geese--are becoming increasingly popular as pets. As such, requests for accurate diagnoses and treatment are being received by the veterinary community from the public. Unlike the food animal and production-oriented aspects of poultry medicine, success with these pet birds is contingent on preserving the human-pet bird bond, as defined by the individual client. This article presents some of this author's observations in diagnostic profiles on some selected disorders of backyard poultry. PMID:11229050

  12. Evaluation of egg production after adoption of biosecurity strategies by backyard poultry farmers in West Bengal

    PubMed Central

    Samanta, I.; Joardar, S. N.; Ganguli, D.; Das, P. K.; Sarkar, U.

    2015-01-01

    Aim: On the basis of identified source of major bacterial infections at four agro-climatic zones in West Bengal the cost-effective biosecurity strategy was formulated for backyard poultry farmers. The aim of the present study was to assess the adoption. So, the study was aimed to detect the adoption level of the formulated biosecurity strategy to mitigate the Salmonella and Escherichia coliweek post-hatch period chicks were contamination level in the sources and its correlation with egg production in West Bengal. Materials and Methods: A questionnaire was prepared querying regarding the biosecurity measures presently followed by the farmers, if any and egg production of their birds. Subsequent to the interview the formulated biosecurity strategy was conveyed. After 3 months, the interview with the same questionnaire was conducted to the same farmers to detect their adoption level. Results: The change in practices were noted in certain parameters which differs significantly (p<0.01 or p<0.05). As a consequence, the average egg production/flock was increased in 3 months after adoption of the strategy (618.2±37.77/flock) in comparison to last 3 months average before adoption of the strategy (495.3±30.00/flock) which also differs significantly (p<0.01). Conclusion: The present study detected the implementation of the biosecurity strategy in backyard poultry farming in West Bengal can substantially benefit the farmers in terms of increased egg production. PMID:27047068

  13. Putative Human and Avian Risk Factors for Avian Influenza Virus Infections in Backyard Poultry in Egypt

    PubMed Central

    Sheta, Basma M.; Fuller, Trevon L.; Larison, Brenda; Njabo, Kevin Y.; Ahmed, Ahmed Samy; Harrigan, Ryan; Chasar, Anthony; Aziz, Soad Abdel; Khidr, Abdel-Aziz A.; Elbokl, Mohamed M.; Habbak, Lotfy Z.; Smith, Thomas B.

    2014-01-01

    Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n=1,084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010–2012. Cloacal and tracheal swabs and serum samples from domestic (n=1242)and wild birds (n=807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n=306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n = 51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F = 15.7, p< 0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F= 29.5, p< 0.0001). PMID:24315038

  14. Prevalence of gastro-intestinal parasites of backyard chickens (Gallus domesticus) in and around Shimoga.

    PubMed

    Javaregowda, Ananda K; Kavitha Rani, B; Revanna, Suresh Patel; Udupa, Ganesh

    2016-09-01

    The present study was conducted for 1 year from March 2010 to February 2011 to identify gastro-intestinal parasites of backyard chickens and to estimate its prevalence in and around Shimoga, a malnad region of Karnataka. A total of 250 gastro-intestinal tracts were collected from backyard chickens for the detection of gastrointestinal parasites. Among the 250 birds screened, 183 (73.2 %) were found positive for gastrointestinal parasites by gross examination of gastrointestinal tract. Out of 183 positive cases, 94 (51.36 %) were found positive for cestodes, includes 73 (77.6 %) Raillietina tetragona, 12 (12.8 %) Raillietina echinobothrida and 9 (9.6 %) Raillietina cesticillus. Whereas, 53 (28.96 %) were found harbouring nematode parasites includes 33 (62.3 %) had Ascaridia galli, 12 (22.6 %) had Heterakis gallinarum and 8 (15.1 %) had both A. galli and H. gallinarum infection. The remaining 36 (19.67 %) had mixed infections of both cestode and nematode parasites. The microscopic examination of the gut contents and faecal samples showed presence of coccidian oocysts and eggs of A. galli, H. gallinarum and Capillaria spp. respectively. PMID:27605824

  15. Molecular identification of Salmonella Infantis isolated from backyard chickens and detection of their resistance genesby PCR

    PubMed Central

    Ghoddusi, A; Nayeri Fasaei, B; Karimi, V; Ashrafi Tamai, I; Moulana, Z; Zahraei Salehi, T

    2015-01-01

    This study aims at molecular identification of Salmonella Infantis isolated from backyard chickens and the detection of their antibiotic resistance genes. A total of 46 Salmonella-suspected samples isolated from backyard chickens of northern Iran were collected. Serotyping was done by the traditional method and then confirmed by PCR. Antimicrobial susceptibility of the isolates against 13 antimicrobial agents was determined by the standard disk diffusion method. There were 44 samples identified as Salmonella. Serotyping results showed that all 44 isolates belonged to serogroup C1 and serovar Infantis. The most resistance observed was to tetracycline and doxycycline (100%), chloramphenicol (79%) and florfenicol (72%). The floR, catI, tetA and tetG genes were used for the detection of florfenicol chloramphenicol and tetracycline resistance. In order to identify the phenotypic resistance in strains which showed resistance genes by PCR, colony PCR and culture on plates each containing antibiotic was performed simultaneously. All the Salmonella Infantis resistant to florfenicol and chloramphenicol harbored floR and catI. None of the Salmonella resistant to tetracycline carried tetA or tetG. The result of colony PCR and culture in antibiotic medium confirmed the results of PCR and indicated phenotypic resistance in these samples. PMID:27175192

  16. Molecular detection of infectious bronchitis and avian metapneumoviruses in Oman backyard poultry.

    PubMed

    Al-Shekaili, Thunai; Baylis, Matthew; Ganapathy, Kannan

    2015-04-01

    Infectious bronchitis virus (IBV) and avian metapneumovirus (aMPV) are economically important viral pathogens infecting chickens globally. Identification of endemic IBV and aMPV strains promotes better control of both diseases and prevents production losses. Orophrayngeal swab samples were taken from 2317 birds within 243 different backyard flocks in Oman. Swabs from each flock were examined by RT-PCR using part-S1 and G gene primers for IBV and aMPV respectively. Thirty-nine chicken flocks were positive for IBV. Thirty two of these were genotyped and they were closely related to 793/B, M41, D274, IS/1494/06 and IS/885/00. 793/B-like IBV was also found in one turkey and one duck flock. Five flocks were positive for aMPV subtype B. Though no disease was witnessed at the time of sampling, identified viruses including variant IBV strains, may still pose a threat for both backyard and commercial poultry in Oman. PMID:25613085

  17. Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt.

    PubMed

    Sheta, Basma M; Fuller, Trevon L; Larison, Brenda; Njabo, Kevin Y; Ahmed, Ahmed Samy; Harrigan, Ryan; Chasar, Anthony; Abdel Aziz, Soad; Khidr, Abdel-Aziz A; Elbokl, Mohamed M; Habbak, Lotfy Z; Smith, Thomas B

    2014-01-10

    Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n=1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010-2012. Cloacal and tracheal swabs and serum samples from domestic (n=1242) and wild birds (n=807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n=306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n=51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F=15.7, p<0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F=29.5, p<0.0001). PMID:24315038

  18. "Regime of Truth" as a Serendipitous Event: An Essay Concerning the Relationship between Research Data and the Generation of Ideas.

    ERIC Educational Resources Information Center

    Garratt, Dean

    1998-01-01

    Argues that realist researchers regard serendipitous events in research with suspicion, resulting in the lack of analysis of the role of serendipity in the generation of research ideas. Analyzes the significance and impact of serendipity in the process of a case study. Deliberates the problematic nature of constructing research stories. (DSK)

  19. Serendipitous discovery and X-ray structure of a human phosphate binding apolipoprotein.

    PubMed

    Morales, Renaud; Berna, Anne; Carpentier, Philippe; Contreras-Martel, Carlos; Renault, Frédérique; Nicodeme, Murielle; Chesne-Seck, Marie-Laure; Bernier, François; Dupuy, Jérôme; Schaeffer, Christine; Diemer, Hélène; Van-Dorsselaer, Alain; Fontecilla-Camps, Juan C; Masson, Patrick; Rochu, Daniel; Chabriere, Eric

    2006-03-01

    We report the serendipitous discovery of a human plasma phosphate binding protein (HPBP). This 38 kDa protein is copurified with the enzyme paraoxonase. Its X-ray structure is similar to the prokaryotic phosphate solute binding proteins (SBPs) associated with ATP binding cassette transmembrane transporters, though phosphate-SBPs have never been characterized or predicted from nucleic acid databases in eukaryotes. However, HPBP belongs to the family of ubiquitous eukaryotic proteins named DING, meaning that phosphate-SBPs are also widespread in eukaryotes. The systematic absence of complete genes for eukaryotic phosphate-SBP from databases is intriguing, but the astonishing 90% sequence conservation between genes belonging to evolutionary distant species suggests that the corresponding proteins play an important function. HPBP is the only known transporter capable of binding phosphate ions in human plasma and may become a new predictor of or a potential therapeutic agent for phosphate-related diseases such as atherosclerosis. PMID:16531243

  20. OMCat: Catalogue of Serendipitous Sources Detected with the XMM-Newton Optical Monitor

    NASA Technical Reports Server (NTRS)

    Kuntz, K. D.; Harrus, Ilana; McGlynn, Thomas A.; Mushotsky, Richard F.; Snowden, Steven L.

    2007-01-01

    The Optical Monitor Catalogue of serendipitous sources (OMCat) contains entries for every source detected in the publically available XMM-Newton Optical Monitor (OM) images taken in either the imaging or "fast" modes. Since the OM records data simultaneously with the X-ray telescopes on XMM-Newton, it typically produces images in one or more near-UV/optical bands for every pointing of the observatory. As of the beginning of 2006, the public archive had covered roughly 0.5% of the sky in 2950 fields. The OMCat is not dominated by sources previously undetected at other wavelengths; the bulk of objects have optical counterparts. However, the OMCat can be used to extend optical or X-ray spectral energy distributions for known objects into the ultraviolet, to study at higher angular resolution objects detected with GALEX, or to find high-Galactic-latitude objects of interest for UV spectroscopy.

  1. Serendipitous Meta-Transcriptomics: The Fungal Community of Norway Spruce (Picea abies).

    PubMed

    Delhomme, Nicolas; Sundström, Görel; Zamani, Neda; Lantz, Henrik; Lin, Yao-Cheng; Hvidsten, Torgeir R; Höppner, Marc P; Jern, Patric; Van de Peer, Yves; Lundeberg, Joakim; Grabherr, Manfred G; Street, Nathaniel R

    2015-01-01

    After performing de novo transcript assembly of >1 billion RNA-Sequencing reads obtained from 22 samples of different Norway spruce (Picea abies) tissues that were not surface sterilized, we found that assembled sequences captured a mix of plant, lichen, and fungal transcripts. The latter were likely expressed by endophytic and epiphytic symbionts, indicating that these organisms were present, alive, and metabolically active. Here, we show that these serendipitously sequenced transcripts need not be considered merely as contamination, as is common, but that they provide insight into the plant's phyllosphere. Notably, we could classify these transcripts as originating predominantly from Dothideomycetes and Leotiomycetes species, with functional annotation of gene families indicating active growth and metabolism, with particular regards to glucose intake and processing, as well as gene regulation. PMID:26413905

  2. Search for serendipitous TNO occultation events in X-rays with Athena

    NASA Astrophysics Data System (ADS)

    Chang, Hsiang-Kuang; Liu, Chih-Yuan; Shang, Jie-Rou

    2015-09-01

    Trans-Neptunian Objects (TNOs), which include Kuiper Belt Objects (KBOs) and yet-to-discover Oort Cloud Objects, are an important population of members of the solar system. Its population properties, such as size distribution, carry information imprinted during the early epoch of the solar system formation. TNOs smaller than about ten kilometers are not directly observable. Their existence, however, may be detected through occultation events of background targets that they cause. Search for such serendipitous occultation events have been conducted in optical and X-ray bands. Since the Fresnel scale is about 30 times smaller in X-rays, using X-ray occultation events one may explore TNOs smaller than that can be done in optical bands. Here I will report X-ray sources suitable for such a study with Athena observations. The estimated Athena detection rate of occultation events, based on different model assumptions of TNO size distribution, will also be presented.

  3. Emissions of polychlorinated dibenzodioxins and dibenzofurans and polychlorinated biphenyls from uncontrolled burning of garden and domestic waste (backyard burning).

    PubMed

    Hedman, Björn; Näslund, Morgan; Nilsson, Calle; Marklund, Stellan

    2005-11-15

    To assess emissions of dioxins (chlorinated dibenzodioxins and dibenzofurans) and PCB from uncontrolled domestic combustion of waste ("backyard burning"), test combustions in barrels and open fires were monitored. The waste fuels used were garden waste, paper, paper and plastic packaging, refuse-derived fuel (RDF), PVC, and electronic scrap. Combustions including PVC and electronic scrap emitted several orders of magnitude more dioxins than the other waste fuels. Emissions from the other fuels had considerable variations, but the levels were difficult to relate to waste composition. Emission factors of PCDD/F and PCB from the backyard burning ranged from 2.2 to 13 000 ng (WHO-TEQ)/kg. The levels found in ash usually were less than 5% of the total. For assessment of total emissions of dioxins and PCB from backyard burning of low and moderately contaminated wastes, an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested. These figures implythat combusting waste in the backyard could contribute substantially to total emissions, even if the amounts of fuel involved are equivalent to just a few tenths of a percent of the amounts combusted in municipal waste incinerators. PMID:16323778

  4. Using Implementation and Program Theory to Examine Communication Strategies in National Wildlife Federation's Backyard Wildlife Habitat Program

    ERIC Educational Resources Information Center

    Palmer, Dain; Dann, Shari L.

    2004-01-01

    Our evaluative approach used implementation theory and program theory, adapted from Weiss (1998) to examine communication processes and results for a national wildlife habitat stewardship education program. Using a mail survey of 1427 participants certified in National Wildlife Federation's (NWF) Backyard Wildlife Habitat (BWH) program and a study…

  5. Likelihood of mated females of Anastrepha suspensa (Diptera: Tephritidae) entering an area from infested grapefruits discarded onto backyard compost piles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Backyard composting of infested fruit is a pathway for entry of exotic fruit flies. Experimentally infested grapefruits were discarded onto forty compost pile replicates. Males and possibly-mated females emerged from 43% (17) of the piles. From this experiment, based on the number of fruit discar...

  6. Non-experimental validation of ethnoveterinary plants and indigenous knowledge used for backyard pigs and chickens in Trinidad and Tobago.

    PubMed

    Lans, C; Georges, K; Brown, G

    2007-06-01

    This paper presents the findings of an exploratory study on ethnoveterinary medicines used for backyard pigs and backyard chickens in Trinidad and Tobago. Research data was collected from 1995 to September 2000. Six plants are used for backyard pigs. Crushed leaves of immortelle (Erythrina pallida, E. micropteryx) are used to remove dead piglets from the uterus. Leaf decoctions of bois canôt (Cecropia peltata) and bamboo (Bambusa vulgaris) are used for labour pains or leaves are fed as a postpartum cleanser. Boiled green papaya fruit (Carica papaya) is fed to pigs to induce milk let-down. The leaves and flowers of male papaya plants (Carica papaya) are fed to deworm pigs. Sour orange juice (Citrus aurantium) is given to pigs to produce lean meat, and coffee grounds are used for scours. Eyebright and plantain leaves (Plantago major) are used for eye injuries of backyard chickens. Worm grass (Chenopodium ambrosioides) and cotton bush (Gossypium species) are used as anthelmintics. Aloe gel (Aloe vera) is used for internal injuries and the yellow sap from the cut Aloe vera leaf or the juice of Citrus limonia is used to purge the birds. A literature review revealed few toxicity concerns and the potential usefulness of the plants. PMID:17944308

  7. BACKYARD COMPOSTING OF INFESTED FRUIT: A POTENTIAL PATHWAY FOR INTRODUCTION OF ANASTREPHA FRUIT FLIES (DIPTERA: TEPHRITIDAE) INTO FLORIDA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disposal of infested fruit directly into the environment is a potential pathway for pest introduction. This study estimated the likelihood of exotic fruit flies entering south Florida through backyard composting. Grapefruits infested with Caribbean fruit fly larvae, Anastrepha suspensa (Loew), wer...

  8. Serendipitous EUV sources detected during the first year of the Extreme Ultraviolet Explorer right angle program

    NASA Technical Reports Server (NTRS)

    Mcdonald, K.; Craig, N.; Sirk, M. M.; Drake, J. J.; Fruscione, A.; Vallerga, J. V.; Malina, R. F.

    1994-01-01

    We report the detection of 114 extreme ultraviolet (EUV; 58 - 740 A) sources, of which 99 are new serendipitous sources, based on observations made with the imaging telescopes on board the Extreme Ultraviolet Explorer (EUVE) during the Right Angle Program (RAP). These data were obtained using the survey scanners and the Deep Survey instrument during the first year of the spectroscopic guest observer phase of the mission, from January 1993 to January 1994. The data set consists of 162 discrete pointings whose exposure times are typically two orders of magnitude longer than the average exposure times during the EUVE all-sky survey. Based on these results, we can expect that EUVE will serendipitously detect approximately 100 new EUV sources per year, or about one new EUV source per 10 sq deg, during the guest observer phase of the EUVE mission. New EUVE sources of note include one B star and three extragalactic objects. The B star (HR 2875, EUVE J0729 - 38.7) is detected in both the Lexan/B (approximately 100 A) and Al/Ti/C (approximately 200 A) bandpasses, and the detection is shown not to be a result of UV leaks. We suggest that we are detecting EUV and/or soft x rays from a companion to the B star. Three sources, EUVE J2132+10.1, EUVE J2343-14.9, and EUVE J2359-30.6 are identified as the active galactic nuclei MKN 1513, MS2340.9-1511, and 1H2354-315, respectively.

  9. Serendipitous EUV sources detected during the first year of the Extreme Ultraviolet Explorer right angle program

    NASA Astrophysics Data System (ADS)

    McDonald, K.; Craig, N.; Sirk, M. M.; Drake, J. J.; Fruscione, A.; Vallerga, J. V.; Malina, R. F.

    1994-11-01

    We report the detection of 114 extreme ultraviolet (EUV; 58 - 740 A) sources, of which 99 are new serendipitous sources, based on observations made with the imaging telescopes on board the Extreme Ultraviolet Explorer (EUVE) during the Right Angle Program (RAP). These data were obtained using the survey scanners and the Deep Survey instrument during the first year of the spectroscopic guest observer phase of the mission, from January 1993 to January 1994. The data set consists of 162 discrete pointings whose exposure times are typically two orders of magnitude longer than the average exposure times during the EUVE all-sky survey. Based on these results, we can expect that EUVE will serendipitously detect approximately 100 new EUV sources per year, or about one new EUV source per 10 sq deg, during the guest observer phase of the EUVE mission. New EUVE sources of note include one B star and three extragalactic objects. The B star (HR 2875, EUVE J0729 - 38.7) is detected in both the Lexan/B (approximately 100 A) and Al/Ti/C (approximately 200 A) bandpasses, and the detection is shown not to be a result of UV leaks. We suggest that we are detecting EUV and/or soft x rays from a companion to the B star. Three sources, EUVE J2132+10.1, EUVE J2343-14.9, and EUVE J2359-30.6 are identified as the active galactic nuclei MKN 1513, MS2340.9-1511, and 1H2354-315, respectively.

  10. Backyard Biodiversity.

    ERIC Educational Resources Information Center

    Thompson, Sarah S.

    2002-01-01

    Describes a field trip experience for the Earth Odyssey project for elementary school students focusing on biodiversity. Introduces the concept of diversity, field work, species richness, and the connection between animals and their habitat. (YDS)

  11. Backyard Ecology.

    ERIC Educational Resources Information Center

    Elser, Monica; Musheno, Birgit; Saltz, Charlene

    2003-01-01

    Describes the Ecology Explorers, the community education component of Arizona State University's Central Arizona Phoenix Long-Term Ecological Research project, which offers teacher internship programs that link university researchers, K-12 teachers, and students in studying urban ecology. Explains that student neighborhoods are dynamic ecosystems…

  12. Backyard Teas.

    ERIC Educational Resources Information Center

    Young, Darrell D.

    1996-01-01

    Describes plants commonly found in residential areas that can be used for making tea: chicory, chickweed, red clover, goldenrod, gill-over-the-ground, pineapple weed, plantain, self-heal, sheep sorrel, and wild strawberry. Includes proper plant name, areas where the plant grows, identifying plant features, what part is used in making tea, and tea…

  13. Revelations in our own backyard: Chandra’s unique Galactic Center discoveries

    PubMed Central

    Markoff, Sera

    2010-01-01

    Before the launch of Chandra, our Galactic Center supermassive black hole, Sgr A*, had never been positively identified outside the radio bands. A great deal has changed in the past decade, starting with the discovery that our own backyard harbors a very weak, yet clearly active, galactic nucleus. I will review how this revelation has been a boon for accretion studies around black holes in general and has helped us place our own Galaxy in context within the active galactic nuclei (AGN) zoology. Chandra’s exquisite resolution has also unveiled entirely new populations of faint sources and transients, as well as regions of extreme gas dynamics and hints of prior, more typical AGN-like activity in our Galactic Center. PMID:20368467

  14. Characterization of backyard poultry production systems and disease risk in the central zone of Chile.

    PubMed

    Hamilton-West, C; Rojas, H; Pinto, J; Orozco, J; Hervé-Claude, L P; Urcelay, S

    2012-08-01

    Backyard poultry production systems (BPS) are an important and widespread form of poultry production. There is a common perception that biosecurity standards in BPS are generally poor and BPS are usually associated with animal diseases and zoonoses. In this study BPS were identified in the vicinity of six wetlands, having these a higher risk of presenting and introducing avian diseases such as HPAI and Newcastle disease, as defined by the national veterinary services, in to Chile's main poultry production area. BPS were characterized through a field questionnaire and the main areas covered by the survey were BPS structure, biosecurity and value chain. The BPS identified in this study share most characteristics on biosecurity, poultry management and product commercialization, but it was possible to identify a certain degree of variation within and among the study sites. BPS in Chile are similar to those in other regions, with a relatively small flock size (average 37 birds), a low level of biosecurity measures and lack of poultry disease management. Management findings include that most farmers used mixed/partial confinement, with low or no biosecurity and disease control measures in place. Eggs were the main output and were used mainly for home consumption or sale at local markets. Sick birds' treatment with drugs approved for other species or for human use could represent a risk to human health, owing to the possible presence of drug residues in poultry products. Despite the different structures of the poultry sector worldwide, BPS can play a major role in disease maintenance and spread because its management conditions characteristics and the lack of animal health services adapted to these production systems. This should be an alert message to the veterinary authorities to improve coverage of veterinary assistance and surveillance activities in backyard poultry production. PMID:21752410

  15. Ensemble spectral variability study of Active Galactic Nuclei from the XMM-Newton serendipitous source catalogue

    NASA Astrophysics Data System (ADS)

    Serafinelli, R.; Vagnetti, F.; Middei, R.

    2016-02-01

    The variability of the X-Ray spectra of active galactic nuclei (AGN) usually includes a change of the spectral slope. This has been investigated for a small sample of local AGNs by Sobolewska and Papadakis [1], who found that slope variations are well correlated with flux variations, and that the spectra are typically steeper in the bright phase (softer when brighter behaviour). Not much information is available for the spectral variability of high-luminosity AGNs and quasars. In order to investigate this phenomenon, we use data from the XMM-Newton Serendipitous Source Catalogue, Data Release 5, which contains X- Ray observations for a large number of active galactic nuclei in a wide luminosity and redshift range, for several different epochs. This allows to perform an ensemble analysis of the spectral variability for a large sample of quasars. We quantify the spectral variability through the spectral variability parameter β, defined by Trevese and Vagnetti [2] as the ratio between the change in spectral slope and the corresponding logarithmic flux variation. We find that the spectral variability of quasars has a softer when brighter behaviour, similarly to local AGNs.

  16. A serendipitous all sky survey for bright objects in the outer solar system

    SciTech Connect

    Brown, M. E.; Drake, A. J.; Djorgovski, S. G.; Graham, M. J.; Mahabal, A.; Donalek, C.; Bannister, M. T.; Schmidt, B. P.; McNaught, R.; Larson, S.; Christensen, E.; Beshore, E.

    2015-02-01

    We use seven year's worth of observations from the Catalina Sky Survey and the Siding Spring Survey covering most of the northern and southern hemisphere at galactic latitudes higher than 20° to search for serendipitously imaged moving objects in the outer solar system. These slowly moving objects would appear as stationary transients in these fast cadence asteroids surveys, so we develop methods to discover objects in the outer solar system using individual observations spaced by months, rather than spaced by hours, as is typically done. While we independently discover eight known bright objects in the outer solar system, the faintest having V=19.8±0.1, no new objects are discovered. We find that the survey is nearly 100% efficient at detecting objects beyond 25 AU for V≲19.1 (V≲18.6 in the southern hemisphere) and that the probability that there is one or more remaining outer solar system object of this brightness left to be discovered in the unsurveyed regions of the galactic plane is approximately 32%.

  17. Novel route to chaetomellic acid A and analogues: serendipitous discovery of a more competent FTase inhibitor.

    PubMed

    Bellesia, Franco; Choi, Seoung-ryoung; Felluga, Fulvia; Fiscaletti, Giuliano; Ghelfi, Franco; Menziani, Maria Cristina; Parsons, Andrew F; Poulter, C Dale; Roncaglia, Fabrizio; Sabbatini, Massimo; Spinelli, Domenico

    2013-01-01

    A new practical route to chaetomellic acid A (ACA), based on the copper catalysed radical cyclization (RC) of (Z)-3-(2,2-dichloropropanoyl)-2-pentadecylidene-1,3-thiazinane, is described. Remarkably, the process entailed: (i) a one-pot preparation of the intermediate N-α-perchloroacyl-2-(Z)-alkyliden-1,3-thiazinanes starting from N-(3-hydroxypropyl)palmitamide, (ii) a two step smooth transformation of the RC products into ACA and (iii) only one intermediate chromatographic purification step. The method offers a versatile approach to the preparation of ACA analogues, through the synthesis of an intermediate maleic anhydride with a vinylic group at the end of the aliphatic tail, a function that can be transformed through a thiol-ene coupling. Serendipitously, the disodium salt of 2-(9-(butylthio)nonyl)-3-methylmaleic acid, that we prepared as a representative sulfurated ACA analogue, was a more competent FTase inhibitor than ACA. This behaviour was analysed by a molecular docking study. PMID:23182215

  18. Novel route to chaetomellic acid A and analogues: serendipitous discovery of a more competent FTase inhibitor

    PubMed Central

    Bellesia, Franco; Choi, Seoung-ryoung; Felluga, Fulvia; Fiscaletti, Giuliano; Ghelfi, Franco; Menziani, Maria Cristina; Parsons, Andrew F.; Poulter, C. Dale; Roncaglia, Fabrizio; Sabbatini, Massimo; Spinelli, Domenico

    2013-01-01

    A new practical route to chaetomellic acid A (ACA), based on the copper catalysed radical cyclization (RC) of (Z)-3-(2,2-dichloropropanoyl)-2-pentadecylidene-1,3-thiazinane, is described. Remarkably, the process entailed: i) a one-pot preparation of the intermediate N-α-perchloroacyl-2-(Z)-alkyliden-1,3-thiazinanes starting from N-(3-hydroxypropyl)palmitamide, ii) a two step smooth transformation of the RC products into ACA and iii) only one intermediate chromatographic purification step. The method offers a versatile approach to the preparation of ACA analogues, through the synthesis of an intermediate maleic anhydride with a vinylic group at the end of the aliphatic tail, a function that can be transformed through a thiol-ene coupling. Serendipitously, the disodium salt of 2-(9-(butylthio)nonyl)-3-methylmaleic acid, that we prepared as a representative sulfurated ACA analogue, was a more competent FTase inhibitor than ACA. This behaviour was analysed by a molecular docking study. PMID:23182215

  19. 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

  20. Versatility of azide in serendipitous assembly of copper(II) magnetic polyclusters.

    PubMed

    Mukherjee, Sandip; Mukherjee, Partha Sarathi

    2013-11-19

    Engineering at the molecular level is one of the most exciting new developments for the generation of functional materials. However, the concept of designing polynuclear extended structures from bottom up is still not mature. Although progress has been made with secondary building units (SBUs) in metal organic frameworks (MOFs), the control seems to be just an illusion when it comes to bridging ligands such as the azide ion. When we say that the azido ligand is versatile in its bridging capabilities, what we mean is that it would be difficult to predict or control its bridging properties. However, this kind of serendipity is not always bad news. For example, scientists have shown that the azido ligand can mediate magnetic exchanges between paramagnetic metals in a predictable fashion (usually depending upon the bonding geometries). Therefore, it is a well-respected ligand in polynuclear assemblies. Serendipitous assemblies offer new magnetic structures that we may not otherwise even think about synthesizing. The azido ligand forms a variety of complexes with copper(II) using different blocking amines or pyridine based ligands. Its structural nature changes upon changing the substitution on amine, as well as the amount of blocking ligand. In principle, if we take any of these complexes and provide more coordination sites to the bridging azido ligands by removing a fraction of the blocking ligands, we can get new complexes with intricate structural networks and therefore different magnetic properties with the same components as used for the parent complex. In this Account, we mainly discuss the development of a number of new topological and magnetic exchange systems synthesized using this concept. Not all of these new complexes can be grouped according to their basic building structures or even by the ratio of the metal to blocking ligand. Therefore, we divided the discussion by the nuclearity of the basic building structures. Some of the complexes with the same

  1. Attempt of Serendipitous Science During the Mojave Volatile Prospector Field Expedition

    NASA Technical Reports Server (NTRS)

    Roush, T. L.; Colaprete, A.; Heldmann, J.; Lim, D. S. S.; Cook, A.; Elphic, R.; Deans, M.; Fluckiger, L.; Fritzler, E.; Hunt, David

    2015-01-01

    On 23 October a partial solar eclipse occurred across parts of the southwest United States between approximately 21:09 and 23:40 (UT), with maximum obscuration, 36%, occurring at 22:29 (UT). During 21-26 October 2014 the Mojave Volatile Prospector (MVP) field expedition deployed and operated the NASA Ames Krex2 rover in the Mojave desert west of Baker, California (Fig. 1, bottom). The MVP field expedition primary goal was to characterize the surface and sub-surface soil moisture properties within desert alluvial fans, and as a secondary goal to provide mission operations simulations of the Resource Prospector (RP) mission to a Lunar pole. The partial solar eclipse provided an opportunity during MVP operations to address serendipitous science. Science instruments on Krex2 included a neutron spectrometer, a near-infrared spectrometer with associated imaging camera, and an independent camera coupled with software to characterize the surface textures of the areas encountered. All of these devices are focused upon the surface and as a result are downward looking. In addition to these science instruments, two hazard cameras are mounted on Krex2. The chief device used to monitor the partial solar eclipse was the engineering development unit of the Near-Infrared Volatile Spectrometer System (NIRVSS) near-infrared spectrometer. This device uses two separate fiber optic fed Hadamard transform spectrometers. The short-wave and long-wave spectrometers measure the 1600-2400 and 2300-3400 nm wavelength regions with resolutions of 10 and 13 nm, respectively. Data are obtained approximately every 8 seconds. The NIRVSS stares in the opposite direction as the front Krex2.

  2. On the Serendipitous Discovery of a Li-rich Giant in the Globular Cluster NGC 362

    NASA Astrophysics Data System (ADS)

    D'Orazi, Valentina; Gratton, Raffaele G.; Angelou, George C.; Bragaglia, Angela; Carretta, Eugenio; Lattanzio, John C.; Lucatello, Sara; Momany, Yazan; Sollima, Antonio

    2015-03-01

    We have serendipitously identified the first lithium-rich giant star located close to the red giant branch bump in a globular cluster. Through intermediate-resolution FLAMES spectra we derived a lithium abundance of A(Li) = 2.55 (assuming local thermodynamical equilibrium), which is extremely high considering the star’s evolutionary stage. Kinematic and photometric analysis confirm the object as a member of the globular cluster NGC 362. This is the fourth Li-rich giant discovered in a globular cluster, but is the only one known to exist at a luminosity close to the bump magnitude. The three previous detections are clearly more evolved, located close to, or beyond, the tip of their red giant branch. Our observations are able to discard the accretion of planets/brown dwarfs, as well as an enhanced mass-loss mechanism as a formation channel for this rare object. While the star sits just above the cluster bump luminosity, its temperature places it toward the blue side of the giant branch in the color-magnitude diagram. We require further dedicated observations to unambiguously identify the star as a red giant: we are currently unable to confirm whether Li production has occurred at the bump of the luminosity function or if the star is on the pre-zero-age horizontal branch. The latter scenario provides the opportunity for the star to have synthesized Li rapidly during the core helium flash or gradually during its red giant branch ascent via some extra mixing process. Based on observations taken with ESO telescopes under program 094.D-0363(A).

  3. Ensemble X-ray variability of active galactic nuclei from serendipitous source catalogues

    NASA Astrophysics Data System (ADS)

    Vagnetti, F.; Turriziani, S.; Trevese, D.

    2011-12-01

    Context. The X-ray variability of the active galactic nuclei (AGN) has been most often investigated with studies of individual, nearby sources, and only a few ensemble analyses have been applied to large samples in wide ranges of luminosity and redshift. Aims: We aim to determine the ensemble variability properties of two serendipitously selected AGN samples extracted from the catalogues of XMM-Newton and Swift, with redshift between ~0.2 and ~4.5, and X-ray luminosities, in the 0.5-4.5 keV band, between ~1043 erg/s and ~1046 erg/s. Methods: We used the structure function (SF), which operates in the time domain, and allows for an ensemble analysis even when only a few observations are available for individual sources and the power spectral density (PSD) cannot be derived. The SF is also more appropriate than fractional variability and excess variance, because these parameters are biased by the duration of the monitoring time interval in the rest-frame, and therefore by cosmological time dilation. Results: We find statistically consistent results for the two samples, with the SF described by a power law of the time lag, approximately as SF ∝ τ0.1. We do not find evidence of the break in the SF, at variance with the case of lower luminosity AGNs. We confirm a strong anti-correlation of the variability with X-ray luminosity, accompanied by a change of the slope of the SF. We find evidence in support of a weak, intrinsic, average increase of X-ray variability with redshift. Conclusions: The change of amplitude and slope of the SF with X-ray luminosity provides new constraints on both single oscillator models and multiple subunit models of variability. Tables 1 and 2 are available in electronic form at http://www.aanda.org

  4. A Serendipitous Line Survey of Titan in the 1.3mm Band

    NASA Astrophysics Data System (ADS)

    Gurwell, Mark A.; Butler, B. J.; Moullet, A.

    2012-10-01

    The millimeter and submillimeter bands are rich in rotational transitions from many molecular species detected and/or expected in the atmosphere of Titan. The lines are typically well-separated, and their line shapes, governed by both pressure broadening in the low- to mid-stratosphere and thermal broadening at higher altitudes, can be used to determine vertical abundance profiles given sufficient spectral resolution. This quantity of spectral lines have made Titan a popular target for millimeter and submillimeter radiotelescopes, which have reported detections of many nitriles along with CO (e.g. Muhleman et al 1984; Marten et al 1988; Tanguy et al 1990; Hidayat et al 1995; Gurwell & Muhleman 1995; Hidayat et al 1997; Marten et al 2002; Gurwell 2004; etc). The submillimeter bands are also covered by instruments on Cassini (CIRS) and Herschel (HIFI,SPIRE). The Submillimeter Array has been in operation for nearly 9 years, and during that time has observed Titan several times as a science target. In addition, Titan is utilized at the SMA as a primary standard for flux calibration in the 1.3mm, 1.1mm and 870 micron transmission windows. While each observation used for flux calibration is typically only 10-20 minutes in length, there have been many such observations during the SMA's operation. Thus, while in many small chunks, this SMA calibration data represents a sizable investment of telescope time, and presents an opportunity for use in a serendipitous line survey. This presentation will describe some initial results from an archival project to locate, calibrate, and combine data from multiple SMA observations of Titan, starting in the 1.3mm band. This will include, to our knowledge, the first reported detections in the millimeter bands of vibrationally excited HC3N (v7=1 and v7=2) and also CH3C2H as well as ongoing searches for HC5N and C2H3CN, and isotopic ratios in HC3N and CH3CN.

  5. Searching for highly obscured AGNs in the XMM-Newton serendipitous source catalog

    NASA Astrophysics Data System (ADS)

    Corral, A.; Georgantopoulos, I.; Watson, M. G.; Rosen, S. R.; Koulouridis, E.; Page, K. L.; Ranalli, P.; Lanzuisi, G.; Mountrichas, G.; Akylas, A.; Stewart, G. C.; Pye, J. P.

    2014-09-01

    The majority of active galactic nuclei (AGNs) are obscured by large amounts of absorbing material that makes them invisible at many wavelengths. X-rays, given their penetrating power, provide the most secure way for finding these AGNs. The XMM-Newton serendipitous source catalog, of which 3XMM-DR4 is the latest version, is the largest catalog of X-ray sources ever produced; it contains about half a million detections. These sources are mostly AGNs. We have derived X-ray spectral fits for very many 3XMM-DR4 sources (≳114 000 observations, corresponding to ~77 000 unique sources), which contain more than 50 source photons per detector. Here, we use a subsample of ≃1000 AGNs in the footprint of the SDSS area (covering 120 deg2) with available spectroscopic redshifts. We searched for highly obscured AGNs by applying an automated selection technique based on X-ray spectral analysis that is capable of efficiently selecting AGNs. The selection is based on the presence of either a) flat rest-frame spectra from a simple power-law fit; b) flat observed spectra from an absorbed power-law fit; c) an absorption turnover, indicative of a high rest-frame column density; or d) the presence of an Fe Kα line with a large equivalent width (>500 eV). We found 81 highly obscured candidate sources. Subsequent detailed manual spectral fits revealed that 28 of them are heavily absorbed by column densities higher than 1023 cm-2. Of these 28 AGNs, 15 are candidate Compton-thick AGNs on the basis of either a high column density, consistent within the 90% confidence level with NH> 1024 cm-2, or a large equivalent width (>500 eV) of the Fe Kα line. Another six are associated with near-Compton-thick AGNs with column densities of ~ 5 × 1023 cm-2. A combination of selection criteria a) and c) for low-quality spectra, and a) and d) for medium- to high-quality spectra, pinpoint highly absorbed AGNs with an efficiency of 80%. Table 4 is available in electronic form at http://www.aanda.org

  6. The Brera multi-scale wavelet Chandra survey. I. Serendipitous source catalogue

    NASA Astrophysics Data System (ADS)

    Romano, P.; Campana, S.; Mignani, R. P.; Moretti, A.; Mottini, M.; Panzera, M. R.; Tagliaferri, G.

    2008-09-01

    We present the BMW-Chandra source catalogue drawn from essentially all Chandra ACIS-I pointed observations with an exposure time in excess of 10 ks public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by Lazzati et al. (1999) and Campana et al. (1999), which can characterise both point-like and extended sources, we identified 21 325 sources. Among them, 16 758 are serendipitous, i.e. not associated with the targets of the pointings, and do not require a non-automated analysis. This makes our catalogue the largest compilation of Chandra sources to date. The 0.5-10 keV absorption corrected fluxes of these sources range from ˜3× 10-16 to 9×10-12 erg cm-2 s-1 with a median of 7× 10-15 erg cm-2 s-1. The catalogue consists of count rates and relative errors in three energy bands (total, 0.5-7 keV; soft, 0.5-2 keV; and hard, 2-7 keV), and source positions relative to the highest signal-to-noise detection among the three bands. The wavelet algorithm also provides an estimate of the extension of the source. We include information drawn from the headers of the original files, as well, and extracted source counts in four additional energy bands, SB1 (0.5-1 keV), SB2 (1-2 keV), HB1 (2-4 keV), and HB2 (4-7 keV). We computed the sky coverage for the full catalogue and for a subset at high Galactic latitude (mid b mid > 20°). The complete catalogue provides a sky coverage in the soft band (0.5-2 keV, S/N =3) of 8 deg2 at a limiting flux of ˜10-13 erg cm-2 s-1, and 2 deg2 at a limiting flux of ˜10-15 erg cm-2 s-1. Furthermore, we present the results of the cross-match with existing catalogues at different wavelengths (FIRST, IRAS, 2MASS, GSC2, and ChaMP). The total numbers of matches with the FIRST, IRASPSC, 2MASS, and GSC2 catalogues obtained after a closest-distance selection are 13, 87, 6700, and 4485, respectively. The catalogue is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130

  7. Avian influenza seroprevalence and biosecurity risk factors in Maryland backyard poultry: a cross-sectional study.

    PubMed

    Madsen, Jennifer M; Zimmermann, Nickolas G; Timmons, Jennifer; Tablante, Nathaniel L

    2013-01-01

    Major implications on a country's economy, food source, and public health. With recent concern over the highly pathogenic avian influenza outbreaks around the world, government agencies are carefully monitoring and inspecting live bird markets, commercial flocks, and migratory bird populations. However, there remains limited surveillance of non-commercial poultry. Therefore, a cross-sectional study was conducted in backyard poultry flocks using a convenience sampling method across three regions of Maryland from July 2011 to August 2011. The objective of this study was to develop a better understanding of the ecology and epidemiology of avian influenza by investigating the prevalence and seroprevalence in this potentially vulnerable population and by evaluating biosecurity risk factors associated with positive findings. Serum, tracheal, and cloacal swabs were randomly collected from 262 birds among 39 registered premises. Analysis indicated bird and flock seroprevalence as 4.2% (11/262) and 23.1% (9/39), respectively. Based on RT-qPCR analysis, none of the samples were found to be positive for AI RNA and evidence of AI hemagglutinin subtypes H5, H7, or H9 were not detected. Although no statistically significant biosecurity associations were identified (p≤0.05), AI seroprevalence was positively associated with exposure to waterfowl, pest control, and location. AI seropositive flocks exposed to waterfowl were 3.14 times as likely to be AI seropositive than those not exposed (p = 0.15). AI seropositive flocks that did not use pest control were 2.5 times as likely to be AI seropositive compared to those that did and AI seropositive flocks located in the Northern region of Maryland were 2.8 times as likely to be AI seropositive than those that were located elsewhere. PMID:23437257

  8. Assessment of the bioaccumulation of metals to chicken eggs from residential backyards.

    PubMed

    Grace, Emily J; MacFarlane, Geoff R

    2016-09-01

    Soil in urban areas contains the residues of past land-uses and practices. Urban farming (keeping chickens, vegetable gardening) requires soil disturbance and can increase exposure of residents to these contaminants. We measured the level of lead, arsenic, cadmium, copper and zinc contaminants in soil and eggs from 26 backyard chicken coops across the Lower Hunter, NSW Australia. We compared the levels of metals in soil to Health Investigation Levels and metals in home-grown eggs to the levels in commercial eggs tested in this study or published by Food Standards Australia New Zealand. The levels of arsenic, cadmium, copper and zinc were low, both in soil and in home-grown eggs and were comparable to commercial eggs tested in this study. The Health Investigation Level for lead in soil (300mglead/kg soil) was exceeded at 7 of the 26 sites. The level of lead in home-grown eggs was generally higher than in commercial eggs. The reference health standard for meat (including chicken), fruit and vegetables of 0.1mglead/kg produce was exceeded in home-grown eggs from 7 of the 26 sites. There was a significant relationship between the lead level in eggs and the lead level in soil accessible to chickens. As soil lead increased, concentrations of lead in eggs tended to increase. No relationship was detected between the lead level in feed and in eggs. We recommend strategies to reduce ingestion of soil by chickens thereby reducing metal contamination in home-grown eggs. PMID:27135588

  9. Seroprevalence of Salmonella and Mycoplasma infection in backyard chickens in the state of Entre Rios in Argentina.

    PubMed

    Xavier, J; Pascal, D; Crespo, E; Schell, H L; Trinidad, J A; Bueno, D J

    2011-04-01

    The present work was conducted to study the seroprevalence of Salmonella, Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS) infection in backyard chickens located in Entre Ríos, Argentina, over 3 periods of time. A total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of Entre Ríos from January to May 2003 (first period), December 2004 to April 2005 (second period), and October 2006 to May 2007 (third period). The prevalence of family farms testing seropositive for Salmonella averaged 23.9, 15.9, and 28.6% during the first, second, and third period, respectively. The highest prevalence of Salmonella-seropositive farms recorded (66.7%) was on farms from Concordia county, and the lowest prevalence (0%) was on farms from La Paz county. In contrast, the prevalence of family farms seropositive for MG averaged 32.8, 55.1, and 76.2% during the first, second, and third periods, respectively. The highest prevalence of MG-seropositive farms (100%) was found in the counties of Victoria and Tala, and the lowest prevalence (8.7%) was found on farms on Colón county. The prevalence of family farms seropositive for MS averaged 68.6 and 100% during the first and second periods, respectively. The highest prevalence of MS-seropositive farms (100%) was on farms in 85% of the counties tested, and the lowest prevalence (21.7%) was on farms from Colón county. Salmonella, MG, and MS infection are present at high levels in backyard chicken farms, and this presents a high risk to commercial poultry production in Entre Ríos, the state with the highest chicken population and density in Argentina. PMID:21406358

  10. Sero-surveillance and risk factors for avian influenza and Newcastle disease virus in backyard poultry in Oman.

    PubMed

    Shekaili, Thunai Al; Clough, Helen; Ganapathy, Kannan; Baylis, Matthew

    2015-11-01

    Avian Influenza (AI) and Newcastle disease (ND) are the most important reportable poultry diseases worldwide. Low pathogenic AI (H9N2) and ND viruses are known to have been circulating in the Middle East, including in Oman, for many decades. However, detailed information on the occurrence of these pathogens is almost completely lacking in Oman. As backyard poultry are not vaccinated against either virus in Oman, this sector is likely to be the most affected poultry production sector for both diseases. Here, in the first survey of AI and ND viruses in backyard poultry in Oman, we report high flock-level seroprevalences of both viruses. Serum and oropharyngeal swabs were taken from 2350 birds in 243 backyard flocks from all regions and governorates of Oman. Information was recorded on location, type of bird and housing type for each sampled farm. Individual bird serum samples were tested using commercial indirect antibody detection ELISA kits. Pooled oropharyngeal samples from each flock were inoculated onto FTA cards and tested by RT-PCR. Samples came from chickens (90.5%), turkeys (2.1%), ducks (6.2%), guinea fowl (0.8%) and geese (0.4%). The bird-level seroprevalence of antibody to AI and ND viruses was 37.5% and 42.1% respectively, and at the flock level it was 84% and 90% respectively. There were statistically significant differences between some different regions of Oman in the seroprevalence of both viruses. Flock-level NDV seropositivity in chickens was significantly associated with AIV seropositivity, and marginally negatively associated with flock size. AIV seropositivity in chickens was marginally negatively associated with altitude. All oropharyngeal samples were negative for both viruses by RT-PCR, consistent with a short duration of infection. This study demonstrates that eight or nine out of ten backyard poultry flocks in Oman are exposed to AI and ND viruses, and may present a risk for infection for the commercial poultry sector in Oman, or wild birds

  11. Chewing lice (Phthiraptera) on chickens (Gallus gallus) from small backyard flocks in the eastern part of the Czech Republic.

    PubMed

    Sychra, O; Harmat, P; Literák, I

    2008-04-15

    One hundred and sixty chickens (Gallus gallus) from 31 small, private backyard flocks in the eastern part of the Czech Republic were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera). At least one species of chewing lice was found on every bird examined. Seven species of chewing lice were identified in all; they had the following prevalences and mean intensities: Goniocotes gallinae (100%; 110 lice), Menopon gallinae (88%; 50), Menacanthus stramineus (48%; 17), Lipeurus caponis (35%; 12), Menacanthus cornutus (12%; 9), Cuclotogaster heterographus (1%; 4) and Goniocotes microthorax (1%; 3). Just two birds from a single flock were heavily infested with the ischnoceran species G. gallinae. PMID:18280661

  12. Exploration of the Kuiper Belt by serendipitous occultations using Ultraphot and MeFos instruments

    NASA Astrophysics Data System (ADS)

    Roques, F.; Guinouard, I.; Doressoundiram, A.; Felenbok, P.; Boissel, Y.; Sicardy, B.

    2008-09-01

    The exploration of the Kuiper Belt is possible using serendipitous stellar occultations [1]. We conducted observations with a multi-photometer instrument at the Pic du Midi Bernard-Lyot 2-m telescope, with Ultracam at the William-Herschel Telescope (WHT) and ESO's Very Large Telescope (VLT) [2]. We detected three events. We also worked on the possibility to use the ESO guiding cameras. Tests were done on ESO's 3.6-m, 2.2-m and NTT telescopes. An Australian team [3] used the fibers spectrograph 6df in straight-through mode on the UK Schmidt telescope (UKST) with the approach of the French analysis. These observations demonstrate that a multi-fibers instrument coupled with fast acquisition is the best tool for exploring the small object population in the Outer Solar System. The optimal configuration for recording several targets simultaneously is the coupling of a fiber set on a large field, with a camera in fast photometry mode. The Paris Observatory team has pushed forward a plan in two steps : (1) The first step is to upgrade MEFOS[5], a 29 fibers spectrograph which has equipped the ESO 3.6-m telescope during 100 nights in 1993. The project is to design a new fiber link and to replace the spectrograph with a fast camera and mount it on the 1.93-m telescope at Observatoire de Haute Provence (South of France). This will provide at very short term a multi image fibre photometric instrument, at very low cost, in the Northern hemisphere. (2) The second step is to build a dedicated instrument, UltraPhot, for the UT2 unit of ESO's Very Large Telescope. This project will provide, also at short term, a very performant instrument for multi-object fast photometry in the Southern hemisphere. The association of fast photometry with a multi-fiber instrument and a 8-meters telescope provides a unique possibility to perform fast precise photometry on several targets in a large field. UltraPhot would use the same fiber positioning system as for FLAMES, a multi-object spectrograph

  13. Virulence repertoire, characterization, and antibiotic resistance pattern analysis of Escherichia coli isolated from backyard layers and their environment in India.

    PubMed

    Samanta, Indranil; Joardar, Siddhartha N; Das, Pradip K; Das, Palas; Sar, Tapas K; Dutta, Tapan K; Bandyopadhyay, Samiran; Batabyal, Subhasis; Isore, Devi P

    2014-03-01

    This study was undertaken to observe the prevalence, serogroup, avian pathogenic Escherichia coli (APEC)-associated virulence gene, randomly amplified polymorphic DNA (RAPD) pattern, and antibiotic resistance genes of E. coli in backyard layers and their environment in India. From the 360 samples of healthy layers and their environment, 272 (75.5%) E. coli were isolated. The majority (28.67%) of them were untypeable. Among the studied virulence genes (papC, tsh, iucC, astA), 52 (14.32%) isolates were found to possess astA, including the isolates from the drinking water of the birds (4/272, 1.47%). These strains belonged to 18 different serogroups. Most of the isolates were typeable by RAPD and they produced different patterns. Phenotypic resistance of the isolates was most frequently observed to erythromycin (95.83%), chloramphenicol (87.52%), and cotrimoxazole (78.26%). None of the isolates was found to possess extended-spectrum beta-lactamases (bla(TEM), bla(SHV), bla(CTX-M) or quinolone resistance (qnrA) genes by PCR. The present study was the first attempt in India to assess APEC distribution in backyard poultry production. PMID:24758111

  14. Comparative possession of Shiga toxin, intimin, enterohaemolysin and major extended spectrum beta lactamase (ESBL) genes in Escherichia coli isolated from backyard and farmed poultry.

    PubMed

    Samanta, I; Joardar, S N; Das, P K; Sar, T K

    2015-01-01

    The present work was conducted to compare the occurrence of Escherichia coli possessing virulence and ESBL genes in backyard and farmed poultry. Three hundred and sixty samples from the poultry kept in backyard system and 120 samples from the farmed birds were collected from West Bengal, India. Among the E. coli isolates of backyard poultry (O2, O10, O25, O55, O60, O106, UT), none of them possessed any of the Shiga toxin genes and eight E. coli isolates (8/272; 2.9%) harboured eaeA gene alone. Whereas among the E. coli isolated from the farmed poultry (O17, O20, O22, O102, O114, O119, rough, UT), four isolates (4/78, 5.1%) harboured stx 1/stx 2 gene and 11 isolates (11/78, 14.1%) possessed eaeA gene. None of the E. coli isolates from the backyard poultry harboured any studied ESBL gene. Whereas 29.4% of E. coli isolates from the farmed poultry were found to possess the ESBL genes. PMID:27175158

  15. Comparative possession of Shiga toxin, intimin, enterohaemolysin and major extended spectrum beta lactamase (ESBL) genes in Escherichia coli isolated from backyard and farmed poultry

    PubMed Central

    Samanta, I.; Joardar, S. N.; Das, P. K.; Sar, T. K.

    2015-01-01

    The present work was conducted to compare the occurrence of Escherichia coli possessing virulence and ESBL genes in backyard and farmed poultry. Three hundred and sixty samples from the poultry kept in backyard system and 120 samples from the farmed birds were collected from West Bengal, India. Among the E. coli isolates of backyard poultry (O2, O10, O25, O55, O60, O106, UT), none of them possessed any of the Shiga toxin genes and eight E. coli isolates (8/272; 2.9%) harboured eaeA gene alone. Whereas among the E. coli isolated from the farmed poultry (O17, O20, O22, O102, O114, O119, rough, UT), four isolates (4/78, 5.1%) harboured stx1/stx2 gene and 11 isolates (11/78, 14.1%) possessed eaeA gene. None of the E. coli isolates from the backyard poultry harboured any studied ESBL gene. Whereas 29.4% of E. coli isolates from the farmed poultry were found to possess the ESBL genes. PMID:27175158

  16. Development of a low-dose fast-dissolving tablet formulation of Newcastle disease vaccine for low-cost backyard poultry immunisation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The immunization of backyard poultry in rural and peri-urban areas worldwide is critical for providing adequate nutrition and income for small farmers and for ensuring global food security. A vaccine presentation for flocks of 30 to 50 birds that is stable at ambient temperatures could make it affor...

  17. The Impact of Densification by Means of Informal Shacks in the Backyards of Low-Cost Houses on the Environment and Service Delivery in Cape Town, South Africa

    PubMed Central

    Govender, Thashlin; Barnes, Jo M.; Pieper, Clarissa H.

    2011-01-01

    This paper investigates the state-sponsored low cost housing provided to previously disadvantaged communities in the City of Cape Town. The strain imposed on municipal services by informal densification of unofficial backyard shacks was found to create unintended public health risks. Four subsidized low-cost housing communities were selected within the City of Cape Town in this cross-sectional survey. Data was obtained from 1080 persons with a response rate of 100%. Illegal electrical connections to backyard shacks that are made of flimsy materials posed increased fire risks. A high proportion of main house owners did not pay for water but sold water to backyard dwellers. The design of state-subsidised houses and the unplanned housing in the backyard added enormous pressure on the existing municipal infrastructure and the environment. Municipal water and sewerage systems and solid waste disposal cannot cope with the increased population density and poor sanitation behaviour of the inhabitants of these settlements. The low-cost housing program in South Africa requires improved management and prudent policies to cope with the densification of state-funded low-cost housing settlements. PMID:21695092

  18. A serendipitous discovery that in situ proteolysis is essential for the crystallization of yeast CPSF-100 (Ydh1p)

    SciTech Connect

    Mandel, Corey R.; Gebauer, Damara; Zhang, Hailong; Tong, Liang

    2006-10-01

    Proteolysis in situ by a protease secreted by a contaminating fungus is essential for the crystallization of yeast CPSF-100. The cleavage and polyadenylation specificity factor (CPSF) complex is required for the cleavage and polyadenylation of the 3′-end of messenger RNA precursors in eukaryotes. During structural studies of the 100 kDa subunit (CPSF-100, Ydh1p) of the yeast CPSF complex, it was serendipitously discovered that a solution that is infected by a fungus (subsequently identified as Penicillium) is crucial for the crystallization of this protein. Further analyses suggest that the protein has undergone partial proteolysis during crystallization, resulting in the deletion of an internal segment of about 200 highly charged and hydrophilic residues, very likely catalyzed by a protease secreted by the fungus. With the removal of this segment, yeast CPSF-100 (Ydh1p) has greatly reduced solubility and can be crystallized in the presence of a minute amount of precipitant.

  19. A Serendipitous Discover that in situ Proteolysis is Essential for the Crystallization of Yeast CPSF-100 (Ydh1p)

    SciTech Connect

    Mandel,C.; Gebauer, D.; Zhang, H.; Tong, L.

    2006-01-01

    The cleavage and polyadenylation specificity factor (CPSF) complex is required for the cleavage and polyadenylation of the 3'-end of messenger RNA precursors in eukaryotes. During structural studies of the 100 kDa subunit (CPSF-100, Ydh1p) of the yeast CPSF complex, it was serendipitously discovered that a solution that is infected by a fungus (subsequently identified as Penicillium) is crucial for the crystallization of this protein. Further analyses suggest that the protein has undergone partial proteolysis during crystallization, resulting in the deletion of an internal segment of about 200 highly charged and hydrophilic residues, very likely catalyzed by a protease secreted by the fungus. With the removal of this segment, yeast CPSF-100 (Ydh1p) has greatly reduced solubility and can be crystallized in the presence of a minute amount of precipitant.

  20. A novel oxy-oxonia(azonia)-cope reaction: serendipitous discovery and its application to the synthesis of macrocyclic musks.

    PubMed

    Zou, Yue; Zhou, Lijun; Ding, Changming; Wang, Quanrui; Kraft, Philip; Goeke, Andreas

    2014-10-01

    This brief review, including new experimental results, is the summary of a talk at the GDCh conference 'flavors & fragrances 2013' in Leipzig, Germany, 11th-13th September, 2013. Musk odorants are indispensable in perfumery to lend sensuality to fine fragrances, a nourishing effect to cosmetics, and a comforting feeling to laundry. We have recently found serendipitously a new oxy-oxonia-Cope rearrangement. In this account, we review the background of oxonia-sigmatropic rearrangements and the discovery of this novel reaction. Special attention is focused on the versatile lactone and lactam formation reactions via [n+4] ring enlargement and the macrocyclization in the synthesis of new macrocyclic musks. The synthesized structures provide new insights into the structure-odor relationships of musks. PMID:25329787

  1. Prevalence of ectoparasites in free-range backyard chickens, domestic pigeons (Columba livia domestica) and turkeys of Kermanshah province, west of Iran.

    PubMed

    Rezaei, Farid; Hashemnia, Mohammad; Chalechale, Abdolali; Seidi, Shahin; Gholizadeh, Maryam

    2016-06-01

    This study was carried out on free-range backyard chickens, domestic pigeons (Columba livia domestica) and turkeys from May 2012 to April 2013 to determine the prevalence and identify the species of ectoparasites in Kermanshah province, west of Iran. Of the total of 600 free-range backyard chickens (185 ♂ and 415 ♀), 700 domestic pigeons (278 ♂ and 422 ♀) and 150 turkeys (53 ♂ and 97 ♀), 389 (64.83 %), 608 (86.85 %) and 54 (36 %) were infected with one or more parasites respectively. Eleven ectoparasites species including five of lice (50.16 % Menacanthus stramineus, 13.66 % Menopon gallinae, 4.83 % Cuclotogaster heterographus, 5.16 % Goniocotes gallinae, 2.33 % Goniodes gigas), three of mites (26.33 % Dermanyssus gallinae, 8.5 % Ornithonyssus bursa, 7 % Cnemidocoptes mutans), one of tick (78.66 % Argas persicus) and two of flea (12.33 % Echidnophaga gallinacea, 2 % Pulex irritans) were found in the backyard chickens. The domestic pigeons were infected with six species of parasites including: Columbicola columbae (61.7 %), M. gallinae (10.43 %), M. stramineus (9 %), D. gallinae (8.28 %), Argas reflexus (74.14 %) and Pseudolynchia canariensis (27.7 %). The ectoparasites species recorded in turkeys were M. gallinae (14 %), M. stramineus (8 %), D. gallinae (12.66 %), C. mutans (6 %), A. persicus (24.66 %) and E. gallinacean (6 %). This is the first survey to determine the prevalence and identify the species of ectoparasites among free-range backyard chicken, domestic pigeons and turkeys in Kermanshah province. The high prevalence rate of ectoparasites in free-range backyard chickens and domestic pigeons indicates that parasitic infection is a common problem in this area. PMID:27413319

  2. Beyond the NIMBY (not-in-my-backyard) impasse II: Public participation in an age of distrust

    SciTech Connect

    Peelle, E.

    1988-01-01

    With the intensification of not-in-my-backyard (NIMBY) responses to both nuclear and chemical waste management and facility siting, we revisit public participation goals, processes, mechanisms and results to evaluate the uses and limits of public participation for achieving legitimate siting decisions. The deepening loss of trust of the American public in most institutions jeopardizes all preemptive nuclear and hazardous waste facility siting decisions, and carefully structured public participation efforts including some form of power sharing offer the best hope of devising legitimate and durable decisions. We review the key factors in the general siting milieu as well as the thickets of public participation-public involvement. Outcomes of six public participation (PP) case studies are presented and analyzed for problems as well as common factors contributing to their success or failure. The uses as well as the limits of PP in complex nuclear and hazardous waste management and siting processes are considered. 38 refs., 1 tab.

  3. Concurrent Fowlpox and Candidiasis Diseases in Backyard Chickens with Unusual Pox Lesions in the Bursa of Fabricius.

    PubMed

    Ogasawara, Fusae; Yamamoto, Yu; Sato, Yasuo; Fukunari, Kazuhiro; Murata, Ken-Ichi; Yaegashi, Gakuji; Goto, Makiko; Murakami, Ryukoh

    2016-09-01

    Concurrent fowlpox and candidiasis diseases occurred in a backyard chicken flock. Four deceased chickens (one Nagoya breed and three white silkie chickens) were examined for diagnosis. At necropsy, white curd-like plaques were observed in the crop. Fungal elements that stained positive for Candida albicans with immunohistochemistry were distributed throughout the tongue, choanal mucosa, esophagus, and crop. Typical fowlpox lesions, composed of proliferating epithelial cells with ballooning degeneration and viral intracytoplasmic inclusions, were observed in the conjunctiva, nasal mucosa, and skin around the cloaca. Interestingly, hyperplastic interfollicular epithelium with rare virus inclusions was observed in the bursa of Fabricius (BF). Some bursal follicles were replaced by proliferating epithelial cells. These proliferating cells immunohistochemically stained positive for cytokeratin. PCR and subsequent genetic sequencing detected the C. albicans gene in the crop, and fowlpox virus genes in the BF. These results indicate that this outbreak was a rare presentation of fowlpox in spontaneously infected chickens, with unusual pox lesions in the BF. PMID:27610735

  4. Stockmanship Competence and Its Relation to Productivity and Economic Profitability: The Context of Backyard Goat Production in the Philippines

    PubMed Central

    Alcedo, M. J.; Ito, K.; Maeda, K.

    2015-01-01

    A stockperson has a significant influence on the productivity and welfare of his animals depending on his stockmanship competence. In this study, stockmanship competence (SC) is defined as the capacity of the stockperson to ensure the welfare of his animals by providing his animals’ needs. The study was conducted to evaluate the SC of backyard goat raisers and examine its relationship to goat productivity and economic profitability. There were 101 respondents for this study who have all undertaken farmer livestock school on integrated goat management (FLS-IGM). Interview was conducted in Region I, Philippines on September 3 to 30, 2012 and March 4 to 17, 2013. Data on SC, goat productivity and farmer’s income were gathered. Questions regarding SC were formulated based on the Philippine Recommendations for Goat Production and from other scientific literature. Housing, feeding, breeding and health and husbandry management were the indicators used in computing stockmanship competence index score (SCIS). Pearson correlation using Statistical Package for Social Science (SPSS) was carried out to analyse the relationship between SCIS, productivity and income. Based from the results of the study, a majority of the respondents raised native and upgraded goats. The computed mean SCIS before and after undergoing FLS-IGM were 38.52% and 75.81% respectively, a percentage difference of 65.23%. Both index scores resulted in significant differences in productivity and income. The median mature weight and mortality rate of goats before FLS-IGM was 14 kg and 30% respectively. After FLS-IGM, median mature weight was 19 kg and mortality rate decreased from 30% to 11.11%. Likewise, fewer goat diseases were observed by farmers who were able to undergo FLS-IGM. With regard to income, there was a 127.34% difference on the median net income derived by farmers. Result implies that improved SC could lead not only to increased productivity and income of backyard goat raisers but also to

  5. Detection of T- and B-cell Target Antigens of Fowlpox Virus Isolated from Backyard Chickens in India.

    PubMed

    Roy, Bithi; Joardar, Siddhartha N; Samanta, Indranil; Das, Pradip K; Alam, Sk Sahanawaz; Nandi, Sudip

    2015-06-01

    With the aim of assessing the antigenic characteristics of a circulating pool of fowlpox virus (FPV) that exists in the backyard poultry system in India, one of the field isolates generated was characterized by in vitro immunologic techniques. FPV was isolated from clinically positive fowlpox cases (n  =  10) from the Jhargram (West Midnapur district) and Kakdwip (South 24 Pargana district) areas of West Bengal State, India. Initially, FPV-specific PCR was performed for confirmation of the samples. Isolation of FPV was done using embryonated chicken eggs and the choreoallantoic membrane route. Subsequently, FPV antigen was prepared from chicken embryo fibroblast cell culture-adapted field isolate. Biologic transmission of FPV was performed in Rhode Island red chickens experimentally to assess humoral and cell-mediated immune (CMI) responses. High level of anti-FPV antibodies were observed in test birds as assessed by indirect ELISA. Seroreactive polypeptides (B-cell antigens) of FPV antigen with molecular weights of 44.5, 66.5, 75, 90.5, and 99 kDa were detected by western blot analysis. Significant increases in CMI responses were observed in inoculated chickens as assessed by lymphocyte proliferation assay, cytotoxicity assay, and T-cell immunoblotting. The predominant T-cell antigen of FPV detected had a molecular weight of 66.5 kDa. The present study revealed the antigenic characteristics of FPV that exists in backyard poultry system in West Bengal for the first time, thus exploring the rationality of designing future T- and B-cell vaccines against fowlpox. PMID:26473675

  6. Seroprevalence of Newcastle disease and other infectious diseases in backyard chickens at markets in Eastern Shewa zone, Ethiopia.

    PubMed

    Chaka, H; Goutard, F; Bisschop, S P R; Thompson, P N

    2012-04-01

    This study was conducted to estimate the seroprevalence of Newcastle disease (ND), Pasteurella multocida (PM) infection, Mycoplasma gallisepticum (MG) infection, and infectious bursal disease (IBD) and to assess the level of concurrent seropositivity during the dry and wet seasons of the year 2010. In total, 234 and 216 sera were collected during the dry and wet seasons, respectively, from unvaccinated backyard chickens at 4 live poultry markets in 2 woredas (districts) of Eastern Shewa zone, Ethiopia, and were tested using commercial ELISA kits. The overall seroprevalence of ND, PM, MG, and IBD was 5.9, 66.2, 57.7, and 91.9%, respectively, during the dry season, and 6.0, 63.4, 78.7, and 96.3%, respectively, during the wet season. The seroprevalence of MG was higher (P < 0.001) during the wet season than during the dry season and higher (P = 0.002) in Adami-Tulu-Jido-Kombolcha woreda (74%) than in Ada'a woreda (60%). Area and season had no significant effect on the seroprevalence of ND, IBD, and PM, indicating the widespread presence of those pathogens throughout the year in the study area. Of all the chickens tested, 85.6% had antibodies concurrently to more than one of the pathogens investigated. Birds were concurrently seropositive to more diseases during the wet season (median = 3) than during the dry season (median = 2; P = 0.002). As serology is not able to distinguish between strains, further studies are warranted to better understand the circulating strains, their interactions, and their economic effect on backyard poultry production in Ethiopia. PMID:22399725

  7. Social network analysis used to assess the relationship between the spread of avian influenza and movement patterns of backyard chickens in Ratchaburi, Thailand.

    PubMed

    Poolkhet, Chaithep; Chairatanayuth, Pornsri; Thongratsakul, Sukanya; Kasemsuwan, Suwicha; Rukkwamsuk, Theera

    2013-08-01

    In this study, we describe the movement and trading patterns of the backyard chicken in Ratchaburi, Thailand by using social network analysis with egocentric approach. From questionnaire results, we found that there is a close relationship between chicken owners' houses and fresh markets, and we concluded that this relationship needs attention from authorities to prevent future outbreaks of avian flu. Control measures should be applied over pathways to prevent and control highly pathogenic avian influenza subtype H5N1 in the backyard farming system. Results of our study may be useful to relevant authorities and researchers seeking to understand how H5N1 spreads in Ratchaburi. This may reflect on the spread of H5N1 throughout Thailand. PMID:23528640

  8. Prevalence of parasites and associated risk factors in domestic pigeons (Columba livia domestica) and free-range backyard chickens of Sistan region, east of Iran.

    PubMed

    Radfar, Mohammad Hossein; Khedri, Javad; Adinehbeigi, Keivan; Nabavi, Reza; Rahmani, Khatereh

    2012-10-01

    This study was carried out on free-range backyard chickens and domestic pigeons (Columba livia domestica) from December 2010 to November 2011 to determine the prevalence, intensity and species of internal and external parasites in Sistan region, east of Iran. Of the total of 59 (27 males and 32 females) free-range backyard chickens and 46 (26 males and 20 females) domestic pigeons inspected, 55 (93.22 %) and 39 (84.78 %) were infected respectively. Ten species of free-range backyard chickens parasites were collected from alimentary canals, body, head and neck, comprising of 3 species of nematodes, 4 species of cestodes and 3 species of ectoparasites as follows: Ascaridia galli (16.94 %), Heterakis gallinarum (23.72 %), Subulura brumpti (67.79 %), Raillietina tetragona (35.59 %), Raillietina echinobothrida (27.11 %), Raillietina cesticillus (15.25 %), Choanotaenia infundibulum (40.67 %), Argas persicus (16.94 %), Menopen gallinae (55.93 %) and Menacanthus stramineus (33.89 %). The domestic pigeons were infected with seven species of parasites including 2 species of nematodes, 2 species of cestodes and 3 species of ectoparasites as follows: Ascaridia colombae (15.21 %), Hadjelia truncata (17.39 %), Raillietina tetragona (26.08 %), Raillietina echinobothrida (28.26 %), Argas reflexus (13.04 %), Menopen gallinae (32.60 %), Columbicola Columba (41.30 %). This is the first survey to determine the prevalence and intensity of parasites among free-range backyard chicken and domestic pigeon species in Sistan region. PMID:24082532

  9. Facts are the enemy of truth-reflections on serendipitous discovery and unforeseen developments in asymmetric catalysis.

    PubMed

    Noyori, Ryoji

    2013-01-01

    As Louis Pasteur said, "Chance favors only a prepared mind." Serendipitous events reorienting the pathway of science often occur through the actions of dedicated individuals with unique cultural and educational backgrounds, an original sense of values, and firm principles. Science is the fountainhead of human knowledge and possesses an indispensable cultural value. Science-based technologies and the innovations derived from them are the foundation of the civilized society in which we live today. All scientific endeavors begin with observations, or facts. However, the real goal of research activity is to convert accumulated knowledge to something with new technological, economic, or social value. Innovation is an essential aspect to assure the continued survival of humanity. And often, as my half-century of research reflects, the act of turning facts into values is facilitated by dialogue. Thus, to acquire the necessary combined wisdom, scientists must have ongoing conversations with the societies they serve, as well as with their counterparts in other nations. PMID:23203605

  10. Serendipitous Discovery of a Projected Pair of QSOs Separated by 4.5 arcsec on the Sky

    NASA Astrophysics Data System (ADS)

    Heintz, K. E.; Fynbo, J. P. U.; Krogager, J.-K.; Vestergaard, M.; Møller, P.; Arabsalmani, M.; Geier, S.; Noterdaeme, P.; Ledoux, C.; Saturni, F. G.; Venemans, B.

    2016-07-01

    We present the serendipitous discovery of a projected pair of quasi-stellar objects (QSOs) with an angular separation of Δθ = 4.50 arcsec. The redshifts of the two QSOs are widely different: one, our program target, is a QSO with a spectrum consistent with being a narrow line Seyfert 1 active galactic nucleus at z = 2.05. For this target we detect Lyα, C iv, and C iii]. The other QSO, which by chance was included on the spectroscopic slit, is a Type 1 QSO at a redshift of z = 1.68, for which we detect C iv, C iii], and Mg ii. We compare this system to previously detected projected QSO pairs and find that only about a dozen previously known pairs have smaller angular separation. Based on observations made with the Nordic Optical Telescope, on the island of La Palma jointly operated by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.

  11. Serendipitous Discovery of an Extended X-Ray Jet without a Radio Counterpart in a High-redshift Quasar

    NASA Astrophysics Data System (ADS)

    Simionescu, A.; Stawarz, Ł.; Ichinohe, Y.; Cheung, C. C.; Jamrozy, M.; Siemiginowska, A.; Hagino, K.; Gandhi, P.; Werner, N.

    2016-01-01

    A recent Chandra observation of the nearby galaxy cluster Abell 585 has led to the discovery of an extended X-ray jet associated with the high-redshift background quasar B3 0727+409, a luminous radio source at redshift z = 2.5. This is one of only few examples of high-redshift X-ray jets known to date. It has a clear extension of about 12″, corresponding to a projected length of ∼100 kpc, with a possible hot spot located 35″ from the quasar. The archival high resolution Very Large Array maps surprisingly reveal no extended jet emission, except for one knot about 1.″4 from the quasar. The high X-ray to radio luminosity ratio for this source appears consistent with the \\propto {(1+z)}4 amplification expected from the inverse Compton radiative model. This serendipitous discovery may signal the existence of an entire population of similar systems with bright X-ray and faint radio jets at high redshift, a selection bias that must be accounted for when drawing any conclusions about the redshift evolution of jet properties and indeed about the cosmological evolution of supermassive black holes and active galactic nuclei in general.

  12. A NEW SAMPLE OF BURIED ACTIVE GALACTIC NUCLEI SELECTED FROM THE SECOND XMM-NEWTON SERENDIPITOUS SOURCE CATALOGUE

    SciTech Connect

    Noguchi, Kazuhisa; Terashima, Yuichi; Awaki, Hisamitsu

    2009-11-01

    We present the results of X-ray spectral analysis of 22 active galactic nuclei (AGNs) with a small scattering fraction selected from the Second XMM-Newton Serendipitous Source Catalogue using hardness ratios. They are candidates of buried AGNs, since a scattering fraction, which is a fraction of scattered emission by the circumnuclear photoionized gas with respect to direct emission, can be used to estimate the size of the opening part of an obscuring torus. Their X-ray spectra are modeled by a combination of a power law with a photon index of 1.5-2 absorbed by a column density of approx10{sup 23-24} cm{sup -2}, an unabsorbed power law, narrow Gaussian lines, and some additional soft components. We find that scattering fractions of 20 among 22 objects are less than a typical value (approx3%) for Seyfert 2s observed so far. In particular, those of eight objects are smaller than 0.5%, which are in the range for buried AGNs found in recent hard X-ray surveys. Moreover, [O III] lambda5007 luminosities at given X-ray luminosities for some objects are smaller than those for Seyfert 2s previously known. This fact could be interpreted as a smaller size of optical narrow emission-line regions produced in the opening direction of the obscuring torus. These results indicate that they are strong candidates for the AGN buried in a very geometrically thick torus.

  13. "Not in (or under) my backyard": Geographic proximity and public acceptance of carbon capture and storage facilities.

    PubMed

    Krause, Rachel M; Carley, Sanya R; Warren, David C; Rupp, John A; Graham, John D

    2014-03-01

    Carbon capture and storage (CCS) is an innovative technical approach to mitigate the problem of climate change by capturing carbon dioxide emissions and injecting them underground for permanent geological storage. CCS has been perceived both positively, as an innovative approach to facilitate a more environmentally benign use of fossil fuels while also generating local economic benefits, and negatively, as a technology that prolongs the use of carbon-intensive energy sources and burdens local communities with prohibitive costs and ecological and human health risks. This article extends existing research on the "not in my backyard" (NIMBY) phenomenon in a direction that explores the public acceptance of CCS. We utilize survey data collected from 1,001 residents of the coal-intensive U.S. state of Indiana. Over 80% of respondents express support for the general use of CCS technology. However, 20% of these initial supporters exhibit a NIMBY-like reaction and switch to opposition as a CCS facility is proposed close to their communities. Respondents' worldviews, their beliefs about the local economic benefits that CCS will generate, and their concerns about its safety have the greatest impact on increasing or decreasing the acceptance of nearby facilities. These results lend valuable insights into the perceived risks associated with CCS technology and the possibilities for its public acceptance at both a national and local scale. They may be extended further to provide initial insights into likely public reactions to other technologies that share a similar underground dimension, such as hydraulic fracturing. PMID:24117789

  14. CHARACTERIZATION OF A SAMPLE OF INTERMEDIATE-TYPE AGNs. I. SPECTROSCOPIC PROPERTIES AND SERENDIPITOUS DISCOVERY OF NEW DUAL AGNs

    SciTech Connect

    Benitez, Erika; Cruz-Gonzalez, Irene; Martinez, Benoni; Jimenez-Bailon, Elena; Mendez-Abreu, Jairo; Lopez-Martin, Luis; Fuentes-Carrera, Isaura; Leon-Tavares, Jonathan; Chavushyan, Vahram H.

    2013-01-20

    A sample of 10 nearby intermediate-type active galactic nuclei (AGNs) drawn from the Sloan Digital Sky Survey is presented. The aim of this work is to provide estimations of the black hole (BH) mass for the sample galaxies from the dynamics of the broad-line region. For this purpose, a detailed spectroscopic analysis of the objects was done. Using Baldwin-Phillips-Terlevich diagnostic diagrams, we have carefully classified the objects as true intermediate-type AGNs and found that 80%{sup +7.2%} {sub -17.3%} are composite AGNs. The BH mass estimated for the sample is within 6.54 {+-} 0.16 < log M {sub BH} < 7.81 {+-} 0.14. Profile analysis shows that five objects (J120655.63+501737.1, J121607.08+504930.0, J141238.14+391836.5, J143031.18+524225.8, and J162952.88+242638.3) have narrow double-peaked emission lines in both the red (H{alpha}, [N II] {lambda}{lambda}6548,6583 and [S II] {lambda}{lambda}6716, 6731) and the blue (H{beta} and [O III] {lambda}{lambda}4959, 5007) regions of the spectra, with velocity differences ({Delta}V) between the double peaks within 114 km s{sup -1} < {Delta}V < 256 km s{sup -1}. Two of them, J121607.08+504930.0 and J141238.14+391836.5, are candidates for dual AGNs since their double-peaked emission lines are dominated by AGN activity. In searches of dual AGNs, type 1, type II, and intermediate-type AGNs should be carefully separated, due to the high serendipitous number of narrow double-peaked sources (50% {+-} 14.4%) found in our sample.

  15. A survey of stellar X-ray flares from the XMM-Newton serendipitous source catalogue: HIPPARCOS-Tycho cool stars

    NASA Astrophysics Data System (ADS)

    Pye, J. P.; Rosen, S.; Fyfe, D.; Schröder, A. C.

    2015-09-01

    Context. The X-ray emission from flares on cool (i.e. spectral-type F-M) stars is indicative of very energetic, transient phenomena, associated with energy release via magnetic reconnection. Aims: We present a uniform, large-scale survey of X-ray flare emission. The XMM-Newton Serendipitous Source Catalogue and its associated data products provide an excellent basis for a comprehensive and sensitive survey of stellar flares - both from targeted active stars and from those observed serendipitously in the half-degree diameter field-of-view of each observation. Methods: The 2XMM Catalogue and the associated time-series ("light-curve") data products have been used as the basis for a survey of X-ray flares from cool stars in the Hipparcos-Tycho-2 catalogue. In addition, we have generated and analysed spectrally-resolved (i.e. hardness-ratio), X-ray light-curves. Where available, we have compared XMM OM UV/optical data with the X-ray light-curves. Results: Our sample contains ~130 flares with well-observed profiles; they originate from ~70 stars. The flares range in duration from ~103 to ~104 s, have peak X-ray fluxes from ~10-13 to ~10-11erg cm-2 s-1, peak X-ray luminosities from ~1029 to ~1032erg s-1, and X-ray energy output from ~1032 to ~1035 erg. Most of the ~30 serendipitously-observed stars have little previously reported information. The hardness-ratio plots clearly illustrate the spectral (and hence inferred temperature) variations characteristic of many flares, and provide an easily accessible overview of the data. We present flare frequency distributions from both target and serendipitous observations. The latter provide an unbiased (with respect to stellar activity) study of flare energetics; in addition, they allow us to predict numbers of stellar flares that may be detected in future X-ray wide-field surveys. The serendipitous sample demonstrates the need for care when calculating flaring rates, especially when normalising the number of flares to a total

  16. The Chandra Multi-Wavelength Project (ChaMP): A Serendipitous X-Ray Survey Using Chandra Archival Data

    NASA Technical Reports Server (NTRS)

    Wilkes, Belinda; Lavoie, Anthony R. (Technical Monitor)

    2000-01-01

    The launch of the Chandra X-ray Observatory in July 2000 opened a new era in X-ray astronomy. Its unprecedented, < 1" spatial resolution and low background is providing views of the X-ray sky 10-100 times fainter than previously possible. We have begun to carry out a serendipitous survey of the X-ray sky using Chandra archival data to flux limits covering the range between those reached by current satellites and those of the small area Chandra deep surveys. We estimate the survey will cover about 8 sq.deg. per year to X-ray fluxes (2-10 keV) in the range 10(exp -13) - 6(exp -16) erg cm2/s and include about 3000 sources per year, roughly two thirds of which are expected to be active galactic nuclei (AGN). Optical imaging of the ChaMP fields is underway at NOAO and SAO telescopes using g',r',z' colors with which we will be able to classify the X-ray sources into object types and, in some cases, estimate their redshifts. We are also planning to obtain optical spectroscopy of a well-defined subset to allow confirmation of classification and redshift determination. All X-ray and optical results and supporting optical data will be place in the ChaMP archive within a year of the completion of our data analysis. Over the five years of Chandra operations, ChaMP will provide both a major resource for Chandra observers and a key research tool for the study of the cosmic X-ray background and the individual source populations which comprise it. ChaMP promises profoundly new science return on a number of key questions at the current frontier of many areas of astronomy including solving the spectral paradox by resolving the CXRB, locating and studying high redshift clusters and so constraining cosmological parameters, defining the true, possibly absorbed, population of quasars and studying coronal emission from late-type stars as their cores become fully convective. The current status and initial results from the ChaMP will be presented.

  17. The Serendipitous Doodle

    ERIC Educational Resources Information Center

    Schulman, Dorothy

    1978-01-01

    Serendipity is the gift of finding valuable or agreeable things not sought for and a doodle is an aimless, unconscious, automatic drawing. Here they are combined in order to create imaginative designs. Briefly discusses five principles of design. (Author/RK)

  18. Serendipity Is Not Serendipitous.

    ERIC Educational Resources Information Center

    Krumboltz, John D.

    1998-01-01

    Unplanned events affect everyone's career. Counselors should give up the unfounded assumption that career decisions are the logical outcome of a "true reasoning" process and broaden their view. Counselors should teach clients that unplanned events are a normal part of career development and how to generate unplanned events. (EMK)

  19. The Serendipitous Research Process

    ERIC Educational Resources Information Center

    Nutefall, Jennifer E.; Ryder, Phyllis Mentzell

    2010-01-01

    This article presents the results of an exploratory study asking faculty in the first-year writing program and instruction librarians about their research process focusing on results specifically related to serendipity. Steps to prepare for serendipity are highlighted as well as a model for incorporating serendipity into a first-year writing…

  20. Henri Becquerel: serendipitous brilliance

    NASA Astrophysics Data System (ADS)

    Margaritondo, Giorgio

    2008-06-01

    Serendipity has always been an attendant to great science. Arno Penzias and Robert Wilson discovered the cosmic background radiation after first mistaking it for the effect of pigeon droppings on their microwave antenna. US spy satellites detected gamma-ray bursts when surveying the sky for evidence of secret Soviet nuclear tests during the Cold War. Satyendra Bose arrived at Bose-Einstein statistics only after discovering that a mathematical error explained the experimental data concerning the photoelectric effect. In the words of science-fiction writer Isaac Asimov, "The most exciting phrase in science is not 'Eureka!', but rather, 'That's funny...'.

  1. Development of a low-dose fast-dissolving tablet formulation of Newcastle disease vaccine for low-cost backyard poultry immunisation.

    PubMed

    Lal, M; Zhu, C; McClurkan, C; Koelle, D M; Miller, P; Afonso, C; Donadeu, M; Dungu, B; Chen, D

    2014-05-17

    The immunisation of backyard poultry is critical for maintaining healthy flocks to provide nutrition and income for low-resource farmers worldwide. A vaccine presentation for flocks of less than 50 birds could make it more affordable and accessible, increasing uptake and impact. Fast-dissolving tablets (FDT) of Newcastle disease virus (NDV) vaccine were produced by freeze drying the LaSota NDV strain combined with excipients into tablets containing a small number of doses and packaged in polymer blister sheets. The NDV-FDT vaccine maintained virus stability for more than six months at 4°C, based on plaque assay and egg infectivity dose data. Stability was further confirmed in a challenge study, where the tablet vaccine elicited a strong immune response and provided 100 per cent protection to vaccinated chickens infected with a virulent strain of NDV. The vaccine tablet can be diluted in water (no needle or syringe required) and administered either in drinking water or with a dropper via an intraocular and/or intransal route. Results indicate that FDTs containing a small number of doses are a feasible presentation for backyard poultry farmers. The compact packaging of the FDTs will also provide cost savings in storing and distributing the vaccine in the cold chain. PMID:24591479

  2. Genomic and biological characterization of a velogenic Newcastle disease virus isolated from a healthy backyard poultry flock in 2010

    PubMed Central

    2012-01-01

    Background Newcastle disease virus (NDV) causes severe and economically important disease in poultry around the globe. None of NDV strains in Pakistan have been completely characterized and the role of rural poultry in harbouring NDV is unclear. Since they have a very important role for long-term circulation of the virus, samples were collected from apparently healthy backyard poultry (BYP) flocks. These samples were biologically analyzed using mean death time (MDT) and intracerebral pathogenicity index (ICPI), whereas genotypically characterized by the real-time PCRs coupled with sequencing of the complete genome. Findings Despite of being non-pathogenic for BYP, the isolate exhibited MDT of 49.6 h in embryonated chicken eggs and an ICPI value of 1.5. The F gene based real-time PCR was positive, whereas M-gene based was negative due to substantial changes in the probe-binding site. The entire genome of the isolate was found to be 15192 nucleotides long and encodes for six genes with an order of 3'-NP-P-M-F-HN-L-5'. The F protein cleavage site, an indicative of pathogenicity, was 112RRQKRF117. Complete genome comparison indicated that the RNA dependent RNA polymerase gene was the most and the phosphoprotein was least conserved gene, among all the genes. The isolate showed an Y526Q substitution in the HN protein, which determines neuraminidase receptor binding and fusion activity of NDV. Phylogenetic analysis, based on F and HN genes, classified this isolate into genotype VII, a predominant genotype responsible for ND outbreaks in Asian countries. However, it clustered well apart from other isolates in this genotype to be considered a new subgenotype (VII-f). Conclusions These results revealed that this isolate was similar to virulent strains of NDV and was avirulent in BYP either due to resistance of local breeds or due to other factors such as substantial mutations in the HN protein. Furthermore, we have characterized the first isolate of NDV, which could act as

  3. A hidden pygmy devil from the Philippines: Arulenus miae sp. nov.-a new species serendipitously discovered in an amateur Facebook post
    (Tetrigidae: Discotettiginae).

    PubMed

    Skejo, Josip; Caballero, Joy Honezza S

    2016-01-01

    Arulenus miae Skejo & Caballero sp. nov. is described from Buknidon and Davao, Mindanao, the Philippines. The species was serendipitously found in an amateur photo posted in Orthoptera Facebook group by Leif Gabrielsen. Holotype and paratype are deposited in Nederlands Centrum voor Biodiversiteit in Leiden, the Netherlands. Detailed comparison with Arulenus validispinus Stål, 1877 is given. A new diagnosis of the genus and A. validispinus is given. The paper is part of the revision of the subfamily Discotettiginae. This study provides a good example of how social networks can be used as a modern tool of discovering biodiversity if the regulations of the International Code of the Zoological Nomenclature are followed. A brief insight into habitat and ecology of this rainforest and mountainous species is presented. PMID:27395882

  4. Transiting Exoplanet Survey Satellite (TESS) Community Observer Program including the Science Enhancement Option Box (SEO Box) - 12 TB On-board Flash Memory for Serendipitous Science

    NASA Astrophysics Data System (ADS)

    Schingler, Robert; Villasenor, J. N.; Ricker, G. R.; Latham, D. W.; Vanderspek, R. K.; Ennico, K. A.; Lewis, B. S.; Bakos, G.; Brown, T. M.; Burgasser, A. J.; Charbonneau, D.; Clampin, M.; Deming, L. D.; Doty, J. P.; Dunham, E. W.; Elliot, J. L.; Holman, M. J.; Ida, S.; Jenkins, J. M.; Jernigan, J. G.; Kawai, N.; Laughlin, G. P.; Lissauer, J. J.; Martel, F.; Sasselov, D. D.; Seager, S.; Torres, G.; Udry, S.; Winn, J. N.; Worden, S. P.

    2010-01-01

    The Transiting Exoplanet Survey Satellite (TESS) will perform an all-sky survey in a low-inclination, low-Earth orbit. TESS's 144 GB of raw data collected each orbit will be stacked, cleaned, cut, compressed and downloaded. The Community Observer Program is a Science Enhancement Option (SEO) that takes advantage of the low-radiation environment, technology advances in flash memory, and the vast amount of astronomical data collected by TESS. The Community Observer Program requires the addition of a 12 TB "SEO Box” inside the TESS Bus. The hardware can be built using low-cost Commercial Off-The-Shelf (COTS) components and fits within TESS's margins while accommodating GSFC gold rules. The SEO Box collects and stores a duplicate of the TESS camera data at a "raw” stage ( 4.3 GB/orbit, after stacking and cleaning) and makes them available for on-board processing. The sheer amount of onboard storage provided by the SEO Box allows the stacking and storing of several months of data, allowing the investigator to probe deeper in time prior to a given event. Additionally, with computation power and data in standard formats, investigators can utilize data-mining techniques to investigate serendipitous phenomenon, including pulsating stars, eclipsing binaries, supernovae or other transient phenomena. The Community Observer Program enables ad-hoc teams of citizen scientists to propose, test, refine and rank algorithms for on-board analysis to support serendipitous science. Combining "best practices” of online collaboration, with careful moderation and community management, enables this `crowd sourced’ participatory exploration with a minimal risk and impact on the core TESS Team. This system provides a powerful and independent tool opening a wide range of opportunity for science enhancement and secondary science. Support for this work has been provided by NASA, the Kavli Foundation, Google, and the Smithsonian Institution.

  5. The Backyard Connection.

    ERIC Educational Resources Information Center

    Rentz, Mark

    1997-01-01

    Research on Arizona State University's intensive English program indicates that the majority of students learned about it through family, relatives, or friends in the local community, not through its extensive overseas recruiting techniques or electronic technology. Local recruiting strategies include local English media features and advertising,…

  6. The Backyard Naturalist.

    ERIC Educational Resources Information Center

    Tufts, Craig

    Many wildlife enthusiasts are aware of the need for planting certain flowers, shrubs, and trees to attract animals. Some arrange their yards to provide for food, water, cover, and areas for animals to bear and raise their young. These include city dwellers who create mini-refuges in tiny urban plots and suburbanites who design elaborate…

  7. Danger in the Backyard

    ERIC Educational Resources Information Center

    Crummond, A. H., Jr.

    1969-01-01

    Describes plant tissues that naturally contain substances poisonous to human beings if taken in large amounts. Some of these toxic materials are found in vegetables and fruits, as well as plants we normally don't eat such as yew. Also notes that plants recently sprayed with pesticides are harmful. (BR)

  8. Growing Backyard Textiles

    ERIC Educational Resources Information Center

    Nelson, Eleanor Hall

    1975-01-01

    For those involved in creative work with textiles, the degree of control possible in texture, finish, and color of fiber by growing and processing one's own (perhaps with students' help) can make the experience rewarding. The author describes the processes for flax and nettles and gives tips on necessary equipment. (Author/AJ)

  9. Flare Hybrids

    NASA Astrophysics Data System (ADS)

    Tomczak, M.; Dubieniecki, P.

    2015-12-01

    On the basis of the Solar Maximum Mission observations, Švestka ( Solar Phys. 121, 399, 1989) introduced a new class of flares, the so-called flare hybrids. When they start, they look like typical compact flares (phase 1), but later on, they look like flares with arcades of magnetic loops (phase 2). We summarize the characteristic features of flare hybrids in soft and hard X-rays as well as in the extreme ultraviolet; these features allow us to distinguish flare hybrids from other flares. In this article, additional energy release or long plasma cooling timescales are suggested as possible causes of phase 2. We estimate the frequency of flare hybrids, and study the magnetic configurations favorable for flare hybrid occurrence. Flare hybrids appear to be quite frequent, and the difference between the lengths of magnetic loops in the two interacting loop systems seem to be a crucial parameter for determining their characteristics.

  10. The Swift serendipitous survey in deep XRT GRB fields (SwiftFT). I. The X-ray catalog and number counts

    NASA Astrophysics Data System (ADS)

    Puccetti, S.; Capalbi, M.; Giommi, P.; Perri, M.; Stratta, G.; Angelini, L.; Burrows, D. N.; Campana, S.; Chincarini, G.; Cusumano, G.; Gehrels, N.; Moretti, A.; Nousek, J.; Osborne, J. P.; Tagliaferri, G.

    2011-04-01

    Aims: An accurate census of the active galactic nuclei (AGN) is a key step in investigating the nature of the correlation between the growth and evolution of super massive black holes and galaxy evolution. X-ray surveys provide one of the most efficient ways of selecting AGN. Methods: We searched for X-ray serendipitous sources in over 370 Swift-XRT fields centered on gamma ray bursts detected between 2004 and 2008 and observed with total exposures ranging from 10 ks to over 1 Ms. This defines the Swift Serendipitous Survey in deep XRT GRB fields, which is quite broad compared to existing surveys (~33 square degrees) and medium depth, with a faintest flux limit of 7.2 × 10-16 erg cm-2 s-1 in the 0.5 to 2 keV energy range (4.8 × 10-15 erg cm-2 s-1 at 50% completeness). The survey has a high degree of uniformity thanks to the stable point spread function and small vignetting correction factors of the XRT, moreover is completely random on the sky as GRBs explode in totally unrelated parts of the sky. Results: In this paper we present the sample and the X-ray number counts of the high Galactic-latitude sample, estimated with high statistics over a wide flux range (i.e., 7.2 × 10-16 ÷ ~ 5 × 10-13 erg cm-2 s-1 in the 0.5-2 keV band and 3.4 × 10-15 ÷ ~ 6 × 10-13 erg cm-2 s-1 in the 2-10 keV band). We detect 9387 point-like sources with a detection Poisson probability threshold of ≤ 2 × 10-5, in at least one of the three energy bands considered (i.e. 0.3-3 keV, 2-10 keV, and 0.3-10 keV), for the total sample, while 7071 point-like sources are found at high Galactic-latitudes (i.e. |b| ≥ 20 deg). The large number of detected sources resulting from the combination of large area and deep flux limits make this survey a new important tool for investigating the evolution of AGN. In particular, the large area permits finding rare high-luminosity objects like QSO2, which are poorly sampled by other surveys, adding precious information for the luminosity function

  11. SERENDIPITOUS DISCOVERY OF A MASSIVE cD GALAXY AT z = 1.096: IMPLICATIONS FOR THE EARLY FORMATION AND LATE EVOLUTION OF cD GALAXIES

    SciTech Connect

    Liu, F. S.; Guo Yicheng; Koo, David C.; Trump, Jonathan R.; Barro, Guillermo; Yesuf, Hassen; Faber, S. M.; Cheung, Edmond; Cassata, P.; Koekemoer, A. M.; Grogin, Norman A.; Pentericci, L.; Castellano, M.; Mao, Shude; Xia, X. Y.; Hathi, Nimish P.; Huang, Kuang-Han; Kocevski, Dale; McGrath, Elizabeth J.; and others

    2013-06-01

    We have made a serendipitous discovery of a massive ({approx}5 Multiplication-Sign 10{sup 11} M{sub Sun }) cD galaxy at z = 1.096 in a candidate-rich cluster in the Hubble Ultra Deep Field (HUDF) area of GOODS-South. This brightest cluster galaxy (BCG) is the most distant cD galaxy confirmed to date. Ultra-deep HST/WFC3 images reveal an extended envelope starting from {approx}10 kpc and reaching {approx}70 kpc in radius along the semimajor axis. The spectral energy distributions indicate that both its inner component and outer envelope are composed of an old, passively evolving (specific star formation rate <10{sup -4} Gyr{sup -1}) stellar population. The cD galaxy lies on the same mass-size relation as the bulk of quiescent galaxies at similar redshifts. The cD galaxy has a higher stellar mass surface density ({approx}M{sub *}/R{sub 50}{sup 2}) but a similar velocity dispersion ({approx}{radical}(M{sub *}/R{sub 50})) to those of more massive, nearby cDs. If the cD galaxy is one of the progenitors of today's more massive cDs, its size (R{sub 50}) and stellar mass have had to increase on average by factors of 3.4 {+-} 1.1 and 3.3 {+-} 1.3 over the past {approx}8 Gyr, respectively. Such increases in size and stellar mass without being accompanied by significant increases in velocity dispersion are consistent with evolutionary scenarios driven by both major and minor dissipationless (dry) mergers. If such cD envelopes originate from dry mergers, our discovery of even one example proves that some BCGs entered the dry merger phase at epochs earlier than z = 1. Our data match theoretical models which predict that the continuance of dry mergers at z < 1 can result in structures similar to those of massive cD galaxies seen today. Moreover, our discovery is a surprise given that the extreme depth of the HUDF is essential to reveal such an extended cD envelope at z > 1 and, yet, the HUDF covers only a minuscule region of sky ({approx}3.1 Multiplication-Sign 10{sup -8

  12. SERENDIPITOUS DETECTION OF X-RAY EMISSION FROM THE HOT BORN-AGAIN CENTRAL STAR OF THE PLANETARY NEBULA K 1-16

    SciTech Connect

    Montez, Rodolfo Jr.; Kastner, Joel H. E-mail: jhk@cis.rit.edu

    2013-03-20

    We report the serendipitous detection of point-like X-ray emission from the hot, PG1159-type central star of the planetary nebula (CSPN) K 1-16 by the XMM-Newton and Chandra X-Ray Observatories. The CSPN lies superimposed on a galaxy cluster that includes an X-ray-bright quasar, but we have successfully isolated the CSPN X-ray emission from the strong diffuse background contributed by the quasar and intracluster gas. We have modeled the XMM-Newton and Chandra X-ray data, taking advantage of the contrasting detection efficiencies of the two observatories to better constrain the low-energy spectral response of Chandra's Advanced CCD Imaging Spectrometer. We find that the CSPN X-ray spectrum is well characterized by the combination of a non-local thermodynamic equilibrium model atmosphere with T{sub *} {approx} 135 kK and a carbon-rich, optically thin thermal plasma with T{sub X} {approx} 1 MK. These results for X-ray emission from the K 1-16 CSPN, combined with those obtained for other PG1159-type objects, lend support to the 'born-again' scenario for Wolf-Rayet and PG1159 CSPNe, wherein a late helium shell flash dredges up carbon-rich intershell material and ejects this material into the circumstellar environment.

  13. The Low-Mass X-Ray Binary X1832-330 in the Globular Cluster NGC 6652: A Serendipitous ASCA Observation

    NASA Technical Reports Server (NTRS)

    Mukai, Koji; Smale, Alan P.

    1999-01-01

    The Low Mass X-ray Binary (LMXB) X1832-330 in NGC 6652 is one of about 10 bright X-ray sources to have been discovered in Globular Clusters. We report on a serendipitous ASCA observation of this Globular Cluster LMXB, during which a Type I burst was detected and the persistent, non-burst emission of the source was at its brightest level recorded to date. No orbital modulation was detected, which argues against a high inclination for the X1832-330 system. The spectrum of the persistent emission can be fit with a power law plus a partial covering absorber, although other models are not ruled out. Our time-resolved spectral analysis through the burst shows, for the first time, clear evidence for spectral cooling from kT = 2.4 +/- 0.6 keV to kT = 1.0 +/- 0.1 keV during the decay. The measured peak flux during the burst is approximately 10% of the Eddington luminosity for a 1.4 Solar Mass neutron star. These are characteristic of a Type I burst, in the context of the relatively low quiescent luminosity of X1832-330.

  14. Stellarator hybrids

    SciTech Connect

    Furth, H.P.; Ludescher, C.

    1984-08-01

    The present paper briefly reviews the subject of tokamak-stellarator and pinch-stellarator hybrids, and points to two interesting new possibilities: compact-torus-stellarators and mirror-stellarators.

  15. Modeling the dynamics of backyard chicken flows in traditional trade networks in Thailand: implications for surveillance and control of avian influenza.

    PubMed

    Wiratsudakul, Anuwat; Paul, Mathilde Cécile; Bicout, Dominique Joseph; Tiensin, Thanawat; Triampo, Wannapong; Chalvet-Monfray, Karine

    2014-06-01

    In Southeast Asia, traditional poultry marketing chains have been threatened by epidemics caused by the highly pathogenic avian influenza H5N1 (HPAI H5N1) virus. In Thailand, the trade of live backyard chickens is based on the activities of traders buying chickens from villages and supplying urban markets with chicken meat. This study aims to quantify the flows of chickens traded during a 1-year period in a province of Thailand. A compartmental stochastic dynamic model was constructed to illustrate trade flows of live chickens from villages to slaughterhouses. Live poultry movements present important temporal variations with increased activities during the 15 days preceding the Chinese New Year and, to a lesser extent, other festivals (Qingming Festival, Thai New Year, Hungry Ghost Festival, and International New Year). The average distance of poultry movements ranges from 4 to 25 km, defining a spatial scale for the risk of avian influenza that spread through traditional poultry marketing chains. Some characteristics of traditional poultry networks in Thailand, such as overlapping chicken supply zones, may facilitate disease diffusion over longer distances through combined expansion and relocation processes. This information may be of use in tailoring avian influenza and other emerging infectious poultry disease surveillance and control programs provided that the cost-effectiveness of such scenarios is also evaluated in further studies. PMID:24668078

  16. Antibody response and risk factors for seropositivity in backyard poultry following mass vaccination against highly pathogenic avian influenza and Newcastle disease in Indonesia.

    PubMed

    McLAWS, M; Priyono, W; Bett, B; Al-Qamar, S; Claassen, I; Widiastuti, T; Poole, J; Schoonman, L; Jost, C; Mariner, J

    2015-06-01

    A large-scale mass vaccination campaign was carried out in Java, Indonesia in an attempt to control outbreaks of highly pathogenic avian influenza (HPAI) in backyard flocks and commercial smallholder poultry. Sero-monitoring was conducted in mass vaccination and control areas to assess the proportion of the target population with antibodies against HPAI and Newcastle disease (ND). There were four rounds of vaccination, and samples were collected after each round resulting in a total of 27 293 samples. Sampling was performed irrespective of vaccination status. In the mass vaccination areas, 20-45% of poultry sampled had a positive titre to H5 after each round of vaccination, compared to 2-3% in the control group. In the HPAI + ND vaccination group, 12-25% of the population had positive ND titres, compared to 5-13% in the areas without ND vaccination. The level of seropositivity varied by district, age of the bird, and species (ducks vs. chickens). PMID:25316261

  17. Optimizing early detection of avian influenza H5N1 in backyard and free-range poultry production systems in Thailand.

    PubMed

    Goutard, Flavie L; Paul, Mathilde; Tavornpanich, Saraya; Houisse, Ivan; Chanachai, Karoon; Thanapongtharm, Weerapong; Cameron, Angus; Stärk, Katharina D C; Roger, François

    2012-07-01

    For infectious diseases such as highly pathogenic avian influenza caused by the H5N1 virus (A/H5N1 HP), early warning system is essential. Evaluating the sensitivity of surveillance is a necessary step in ensuring an efficient and sustainable system. Stochastic scenario tree modeling was used here to assess the sensitivity of the A/H5N1 HP surveillance system in backyard and free-grazing duck farms in Thailand. The whole surveillance system for disease detection was modeled with all components and the sensitivity of each component and of the overall system was estimated. Scenarios were tested according to selection of high-risk areas, inclusion of components and sampling procedure, were tested. Nationwide passive surveillance (SSC1) and risk-based clinical X-ray (SSC2) showed a similar sensitivity level, with a median sensitivity ratio of 0.96 (95% CI 0.40-15.00). They both provide higher sensitivity than the X-ray laboratory component (SSC3). With the current surveillance design, the sensitivity of detection of the overall surveillance system when the three components are implemented, was equal to 100% for a farm level prevalence of 0.05% and 82% (95% CI 71-89%) for a level of infection of 3 farms. Findings from this study illustrate the usefulness of scenario-tree modeling to document freedom from diseases in developing countries. PMID:22296731

  18. THE SERENDIPITOUS OBSERVATION OF A GRAVITATIONALLY LENSED GALAXY AT z = 0.9057 FROM THE BLANCO COSMOLOGY SURVEY: THE ELLIOT ARC

    SciTech Connect

    Buckley-Geer, E. J.; Lin, H.; Drabek, E. R.; Allam, S. S.; Tucker, D. L.; Frieman, J. A.; Armstrong, R.; Barkhouse, W. A.; Bertin, E.; Brodwin, M.; Desai, S.; Ngeow, C.-C.; Hansen, S. M.; High, F. W.; Mohr, J. J.; Zenteno, A.; Lin, Y.-T.; Rest, A.; Smith, R. C.; Song, J.

    2011-11-20

    We report on the serendipitous discovery in the Blanco Cosmology Survey (BCS) imaging data of a z = 0.9057 galaxy that is being strongly lensed by a massive galaxy cluster at a redshift of z = 0.3838. The lens (BCS J2352-5452) was discovered while examining i- and z-band images being acquired in 2006 October during a BCS observing run. Follow-up spectroscopic observations with the Gemini Multi-Object Spectrograph instrument on the Gemini-South 8 m telescope confirmed the lensing nature of this system. Using weak-plus-strong lensing, velocity dispersion, cluster richness N{sub 200}, and fitting to a Navarro-Frenk-White (NFW) cluster mass density profile, we have made three independent estimates of the mass M{sub 200} which are all very consistent with each other. The combination of the results from the three methods gives M{sub 200} = (5.1 {+-} 1.3) Multiplication-Sign 10{sup 14} M{sub Sun }, which is fully consistent with the individual measurements. The final NFW concentration c{sub 200} from the combined fit is c{sub 200} = 5.4{sup +1.4}{sub -1.1}. We have compared our measurements of M{sub 200} and c{sub 200} with predictions for (1) clusters from {Lambda}CDM simulations, (2) lensing-selected clusters from simulations, and (3) a real sample of cluster lenses. We find that we are most compatible with the predictions for {Lambda}CDM simulations for lensing clusters, and we see no evidence based on this one system for an increased concentration compared to {Lambda}CDM. Finally, using the flux measured from the [O II]3727 line we have determined the star formation rate of the source galaxy and find it to be rather modest given the assumed lens magnification.

  19. The serendipitous observation of a gravitationally lensed galaxy at z = 0.9057 from the Blanco Cosmology Survey: the Elliot Arc

    DOE PAGESBeta

    Buckley-Geer, E. J.; Lin, H.; Drabek, E. R.; Allam, S. S.; Tucker, D. L.; Armstrong, R.; Barkhouse, W. A.; Bertin, E.; Brodwin, M.; Desai, S.; et al

    2011-11-03

    We report on the serendipitous discovery in the Blanco Cosmology Survey (BCS) imaging data of a z = 0.9057 galaxy that is being strongly lensed by a massive galaxy cluster at a redshift of z = 0.3838. The lens (BCS J2352-5452) was discovered while examining i- and z-band images being acquired in October 2006 during a BCS observing run. Follow-up spectroscopic observations with the GMOS instrument on the Gemini South 8m telescope confirmed the lensing nature of this system. Using weak plus strong lensing, velocity dispersion, cluster richness N200, and fitting to an NFW cluster mass density profile, we havemore » made three independent estimates of the mass M200 which are all very consistent with each other. The combination of the results from the three methods gives M200 = (5.1 x 1.3) x 1014 circle_dot, which is fully consistent with the individual measurements. The final NFW concentration c200 from the combined fit is c200 = 5.4-1.1+1.4. We have compared our measurements of M200 and c200 with predictions for (a) clusters from λCDM simulations, (b) lensing selected clusters from simulations, and (c) a real sample of cluster lenses. We find that we are most compatible with the predictions for λCDM simulations for lensing clusters, and we see no evidence based on this one system for an increased concentration compared to λCDM. Finally, using the flux measured from the [OII]3727 line we have determined the star formation rate (SFR) of the source galaxy and find it to be rather modest given the assumed lens magnification.« less

  20. The serendipitous observation of a gravitationally lensed galaxy at z = 0.9057 from the Blanco Cosmology Survey: the Elliot Arc

    SciTech Connect

    Buckley-Geer, E. J.; Lin, H.; Drabek, E. R.; Allam, S. S.; Tucker, D. L.; Armstrong, R.; Barkhouse, W. A.; Bertin, E.; Brodwin, M.; Desai, S.; Frieman, J. A.; Hansen, S. M.; High, F. W.; Mohr, J. J.; Lin, Y. -T.; Ngeow, C. -C.; Rest, A.; Smith, R. C.; Song, J.; Zenteno, A.

    2011-11-03

    We report on the serendipitous discovery in the Blanco Cosmology Survey (BCS) imaging data of a z = 0.9057 galaxy that is being strongly lensed by a massive galaxy cluster at a redshift of z = 0.3838. The lens (BCS J2352-5452) was discovered while examining i- and z-band images being acquired in October 2006 during a BCS observing run. Follow-up spectroscopic observations with the GMOS instrument on the Gemini South 8m telescope confirmed the lensing nature of this system. Using weak plus strong lensing, velocity dispersion, cluster richness N200, and fitting to an NFW cluster mass density profile, we have made three independent estimates of the mass M200 which are all very consistent with each other. The combination of the results from the three methods gives M200 = (5.1 x 1.3) x 1014 circle_dot, which is fully consistent with the individual measurements. The final NFW concentration c200 from the combined fit is c200 = 5.4-1.1+1.4. We have compared our measurements of M200 and c200 with predictions for (a) clusters from λCDM simulations, (b) lensing selected clusters from simulations, and (c) a real sample of cluster lenses. We find that we are most compatible with the predictions for λCDM simulations for lensing clusters, and we see no evidence based on this one system for an increased concentration compared to λCDM. Finally, using the flux measured from the [OII]3727 line we have determined the star formation rate (SFR) of the source galaxy and find it to be rather modest given the assumed lens magnification.

  1. The "serendipitous brain": Low expectancy and timing uncertainty of conscious events improve awareness of unconscious ones (evidence from the Attentional Blink).

    PubMed

    Lasaponara, Stefano; Dragone, Alessio; Lecce, Francesca; Di Russo, Francesco; Doricchi, Fabrizio

    2015-10-01

    To anticipate upcoming sensory events, the brain picks-up and exploits statistical regularities in the sensory environment. However, it is untested whether cumulated predictive knowledge about consciously seen stimuli improves the access to awareness of stimuli that usually go unseen. To explore this issue, we exploited the Attentional Blink (AB) effect, where conscious processing of a first visual target (T1) hinders detection of early following targets (T2). We report that timing uncertainty and low expectancy about the occurrence of consciously seen T2s presented outside the AB period, improve detection of early and otherwise often unseen T2s presented inside the AB. Recording of high-resolution Event Related Potentials (ERPs) and the study of their intracranial sources showed that the brain achieves this improvement by initially amplifying and extending the pre-conscious storage of T2s' traces signalled by the N2 wave originating in the extra-striate cortex. This enhancement in the N2 wave is followed by specific changes in the latency and amplitude of later components in the P3 wave (P3a and P3b), signalling access of the sensory trace to the network of parietal and frontal areas modulating conscious processing. These findings show that the interaction between conscious and unconscious processing changes adaptively as a function of the probabilistic properties of the sensory environment and that the combination of an active attentional state with loose probabilistic and temporal expectancies on forthcoming conscious events favors the emergence to awareness of otherwise unnoticed visual events. This likely provides an insight on the attentional conditions that predispose an active observer to unexpected "serendipitous" findings. PMID:26142182

  2. Household-level risk factors for Newcastle disease seropositivity and incidence of Newcastle disease virus exposure in backyard chicken flocks in Eastern Shewa zone, Ethiopia.

    PubMed

    Chaka, Hassen; Goutard, Flavie; Roger, Francois; Bisschop, Shahn P R; Thompson, Peter N

    2013-05-01

    A cross-sectional study with repeated sampling was conducted to investigate potential risk factors for Newcastle disease (ND) seropositivity and for incidence of ND virus (NDV) exposure in household flocks of backyard chickens in Eastern Shewa zone, Ethiopia. Data were collected from 260 randomly selected households in 52 villages in Adami Tulu Jido Kombolcha and Ada'a woredas (districts) using a structured questionnaire, and serum samples from chickens were tested for NDV antibodies using a blocking enzyme-linked immunosorbent assay (ELISA). Sampling took place during September 2009 and the same households were again sampled in May 2010. Household-level seroprevalence and incidence of NDV exposure were estimated in various ways using serological results from the two samplings, flock dynamics, and farmers' reports of ND in their flocks. The risk factors were assessed using multivariable mixed-effects logistic regression models. Household-level seroprevalence at the two sampling times was 17.4% and 27.4%, respectively, and the estimated incidence of household-level NDV exposure during the intervening period ranged between 19.7% and 25.5%. At the first sampling, reduced frequency of cleaning of poultry waste was associated with increased odds of seropositivity (OR=4.78; 95% CI: 1.42, 16.11; P=0.01) while hatching at home vs. other sources (buying in replacement birds, receiving as gift or buying fertile eggs) was associated with lower odds of seropositivity, both at the first sampling (OR=0.30; 95% CI: 0.11, 0.82; P=0.02) and the second sampling (OR=0.23; 95% CI: 0.10, 0.52; P<0.001). The risk of NDV exposure was shown to be higher with larger flock size at the beginning of the observation period (OR=3.6; 95% CI: 1.25, 10.39; P=0.02). Using an open water source (pond or river) for poultry compared to closed sources (tap or borehole) was associated with increased risk of NDV exposure (OR=3.14; 95% CI: 1.12, 8.8; P=0.03). The use of a grain supplement (OR=0.14; 95% CI

  3. Prevalence and impact of gastrointestinal helminths on body weight gain in backyard chickens in subtropical and humid zone of Jammu, India.

    PubMed

    Katoch, R; Yadav, Anish; Godara, R; Khajuria, J K; Borkataki, S; Sodhi, S S

    2012-04-01

    Necropsy of gastrointestinal tract of 125 free-range chickens from a subtropical and humid zone of northwestern India revealed four nematode spp. (Ascaridia galli, Heterakis gallinarum, Capillaria spp. and Cheilospirura hamulosa) and four cestode spp. (Raillietina cesticillus, Raillietina echinobothrida, Raillietina tetragona and Amoebotaenia cuneata) The overall prevalence of the helminth parasites was 72.0%. Amongst various helminth species encountered in the region, A. galli emerged out as the most prevalent, followed by H. gallinarum, R. cesticillus and R. echinobothrida. The impact of helminthic infections on body weight gain in growing chickens was investigated. One hundred growing chickens, aged 40 days were randomly assigned to two groups (treated and untreated controls) of 50 birds each. The birds in treated group were given fenbendazole at 7.5 mg per kg body weight in drinking water, while the birds in other group served as untreated controls. At the end of the 90 days of the field trial, the mean body weight gain of untreated controls was 1232.2 ± 7.28 g (13.7 g/day) compared with 1617.6 ± 5.43 g (18.0 g/day) in the treated group. It was associated with a significantly (P < 0.05) higher mean worm burden (32.92 ± 6.12) in untreated controls than the treated group (2.46 ± 1.14). The prevalences of helminthic species and their impact on body weight gain in growing backyard chickens have been discussed. PMID:23543701

  4. Serological monitoring of backyard chickens in Central Macedonia-Greece can detect low transmission of West Nile virus in the absence of human neuroinvasive disease cases.

    PubMed

    Chaintoutis, Serafeim C; Gewehr, Sandra; Mourelatos, Spiros; Dovas, Chrysostomos I

    2016-11-01

    During 2010-13, West Nile virus (WNV) epidemics occurred in Greece with high numbers of human cases. In parallel, WNV serological surveillance utilizing domestic birds was applied mainly in Central Macedonia, as well as in other areas of the country, and allowed efficient detection of WNV activity during this period. The objective of the study was to evaluate the sensitivity of chicken-based WNV surveillance in periods of low-level virus transmission (2014-15) in a well-studied area, i.e. the epicenter of the 2010 WNV epidemic (Central Macedonia), which is considered endemic since then. WNV activity was monitored via determination of antiviral immune responses in juvenile backyard chickens. The birds were sampled twice per transmission period. WNV-specific antibodies were detected by ELISA in 2.8% out of 255 chickens sampled early in the 2014 transmission period (95% CI: 1-6%). Continued virus transmission was detected at the end of the period, as 4.2% out of 240 sampled chickens seroconverted to WNV (95% CI: 2-8%). Although 14 human neuroinvasive cases occurred in Greece during 2014, no such cases were reported in the study area. During the 2015 early warning period, antibodies against WNV were not detected in sampled chickens (n=250, 95% CI: 0-2%). However, humoral immune responses were detected in 6 out of 240 chicken sampled at the end of the transmission period (2.5%; 95% CI: 1-6%), indicating continued WNV activity. No human cases were reported in Greece during 2015. All samples were negative with real-time RT-PCR. Serological surveillance of chickens resulted in identification of areas with low WNV activity levels during 2014-15, and provided indications of its overwintering in Central Macedonia. The findings suggest that surveillance based on serological testing of domestic birds is sensitive and able to detect low-level of WNV enzootic transmission, in the absence of human cases. PMID:27469618

  5. Investigations into Outbreaks of Black Fly Attacks and Subsequent Avian Haemosporidians in Backyard-Type Poultry and Other Exposed Avian Species.

    PubMed

    Jones, Kelli; Johnson, Nora; Yang, Sharon; Stokes, John; Smith, Whitney; Wills, Robert; Goddard, Jerome; Varela-Stokes, Andrea

    2015-03-01

    In late spring of 2009 and 2010, there were reports of severe black fly (Simulium spp., shown in Fig. 1) outbreaks in various counties in Mississippi, especially those in and around the Mississippi River Delta. Complaints were of black flies attacking multiple species of backyard poultry and causing high morbidity and mortality in affected flocks. At several affected locations, black flies were readily observed swarming around and feeding on birds. A large number of these parasites were easily trapped on fly strips (Fig. 2). Multifocal to coalescing cutaneous hemorrhagic lesions, consistent with fly bites, were seen on the birds. Upon necropsy examination, a large number of black flies were also observed in the digestive tract (Fig. 3). Although black flies may cause disease directly, such as cardiopulmonary collapse and anaphylactoid reactions, detection of Leucocytozoon in blood smears (Fig. 4) of affected birds prompted further investigations of this protozoan as a cause of disease. Leucocytozoon spp. are known to be transmitted by black flies and may be associated with morbidity and mortality in birds such as poultry. From June 2009 through July 2012, the investigation included a total collection of 1068 individual blood samples, representing 371 individual premises in 89 counties/parishes across Mississippi (59), Alabama (10), Louisiana (4), and Tennessee (16). Of the 371 premises where blood samples were collected, 96 (26%) were either positive or highly suspected to be positive for Leucocytozoon spp. by blood smear analysis, and 5 (1.2%) were positive for Haemoproteus spp. by blood smear analysis. Attempts to diagnose Leucocytozoon spp. by PCR analysis and sequencing were complicated by coinfections with two closely related haemosporidians (Haemoproteus spp. and Plasmodium spp.). A novel technique involving flow cytometry was also explored. This study discusses the black fly field outbreak, the involvement of haemosporidians, molecular methods for detection

  6. Pasteurella multocida in backyard chickens in Upper Egypt: incidence with polymerase chain reaction analysis for capsule type, virulence in chicken embryos and antimicrobial resistance.

    PubMed

    Mohamed, Moemen A; Mohamed, Mohamed-Wael A; Ahmed, Ahmed I; Ibrahim, Awad A; Ahmed, Mohamed S

    2012-01-01

    The prevalence of Pasteurella multocida strains among 275 backyard chickens from different regions of Upper Egypt was studied. A total of 21 isolates of P. multocida were recovered in 21 out of 275 chickens tested (7.6%) and were confirmed using phenotypic characterisation. Somatic serotyping of the 21 isolates resulted in 12 isolates being classed as serotype A:1 (57.14%), 4 as serotype A:3 (19.05%) and 5 could not be typed (23.8%). Capsular typing, using multiplex polymerase chain reaction (PCR), demonstrated that 18 strains were capsular type A (85.7%), and 3 were type D (14.3%). The present findings suggest that a multiplex capsular PCR could be valuable for the rapid identification of P. multocida in cases of fowl cholera infection. A total of 5 isolates of P. multocida were selected to study their pathogenicity in embryonated chicken eggs instead of conducting a study in mature chickens. The results showed a variation in pathogenicity between the strains tested, namely: serotype A:1 strains caused 80% mortality, in contrast to 20% mortality by type D strains. Pathological findings included severe congestion of the entire embryo, haemorrhaging of the skin, feather follicles and toe, and ecchymotic haemorrhages on the liver of the inoculated embryos. The observations in this study indicate that P. multocida serogroup A could be highly pathogenic for mature chickens and therefore might be a cause of considerable economic losses in commercial production. A total of 10 isolates were subjected to antimicrobial susceptibility to determine the minimal inhibitory concentration of 7 antimicrobials. All isolates were susceptible to ciprofloxacin, florfenicol, streptomycin and sulphamethoxazol with trimethoprim and with varying degrees of sensitivity to the other agents. PMID:22485004

  7. VizieR Online Data Catalog: XMM-Newton Serendipitous Source Catalogue 3XMM-DR4 (XMM-SSC, 2013)

    NASA Astrophysics Data System (ADS)

    Xmm-Newton Survey Science Centre, Consortium

    2013-10-01

    The 3XMM-DR4 catalogue is the third generation catalog of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory, and has been created by the XMM-Newton Survey Science Centre (SSC) on behalf of ESA. The catalog has 2474 more observations and about 178,000 (50%) more detections than the preceding 2XMMi-DR3 catalog, which was made public in April 2010. The history of the versions can be summarized as: ---------------------------------------------------- Name DR# Designation Year Cat. #Sources ---------------------------------------------------- 2XMMp 0 2XMMp-DR0 2006 2XMM 1 2XMM-DR1 2007 IX/39 191870 2XMMi 2 2XMMi-DR2 2008 IX/40 221012 2XMMi-DR3 3 2XMMi-DR3 2010 IX/41 262902 3XMM-DR4 4 3XMM 2013 IX/44 372728 ---------------------------------------------------- The production and content of the 3XMM catalogue is described in the the 3XMM-DR4 User Guide at http://xmmssc-www.star.le.ac.uk/Catalogue/3XMM-DR4/UserGuide_xmmcat.html The "slim" version of the catalogue (file "xmm3r4s.dat") contains one row per unique source, while the the main catalogue has one row per detection. This slim version includes 44 columns, essentially those containing information about the unique sources, while the full catalogue (file "xmm3r4.fit") describes all detections with 318 columns. The slim version also contains a column with links to the LEDAS summary pages. In the case of sources with multiple detections the summary page of the best detection is selected (i.e., the detection with the largest exposure time, summed over all cameras), and the summary page gives cross-links to the other detections. A separate file "summary.dat" contains the key details about the observations used in the construction of the 3XMM-DR4 catalogue. (3 data files).

  8. The 8 O'Clock Arc: A Serendipitous Discovery of a Strongly Lensed Lyman Break Galaxy in the SDSS DR4 Imaging Data

    SciTech Connect

    Allam, Sahar S.; Tucker, Douglas L.; Lin, Huan; Diehl, H.Thomas; Annis, James; Buckley-Geer, Elizabeth J.; Frieman, Joshua A.; /Fermilab /Chicago U., Astron. Astrophys. Ctr.

    2006-11-01

    We report on the serendipitous discovery of the brightest Lyman Break Galaxy (LBG) currently known, a galaxy at z = 2.73 that is being strongly lensed by the z = 0.38 Luminous Red Galaxy (LRG) SDSS J002240.91+143110.4. The arc of this gravitational lens system, which we have dubbed the ''8 o'clock arc'' due to its time of discovery, was initially identified in the imaging data of the Sloan Digital Sky Survey Data Release 4 (SDSS DR4); followup observations on the Astrophysical Research Consortium (ARC) 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this system and led to the identification of the arc's spectrum as that of an LBG. The arc has a spectrum and a redshift remarkably similar to those of the previous record-holder for brightest LBG (MS 1512-cB58, a.k.a ''cB58''), but, with an estimated total magnitude of (g,r,i) = (20.0,19.2,19.0) and surface brightness of ({mu}{sub g}, {mu}{sub r}, {mu}{sub i}) = (23.3, 22.5, 22.3) mag arcsec{sup -2}, the 8 o'clock arc is thrice as bright. The 8 o'clock arc, which consists of three lensed images of the LBG, is 162{sup o}(9.6'') long and has a length-to-width ratio of 6:1. A fourth image of the LBG--a counter-image--can also be identified in the ARC 3.5m g-band images. A simple lens model for the system assuming a singular isothermal ellipsoid potential yields an Einstein radius of {theta}{sub Ein} = 2.91'' {+-} 0.14'', a total mass for the lensing LRG (within the 10.6 {+-} 0.5 h{sup -1} kpc enclosed by the lensed images) of 1.04 x 10{sup 12} h{sup -1} M{sub {circle_dot}}, and a magnification factor for the LBG of 12.3{sub -3.6}{sup +15}. The LBG itself is intrinsically quite luminous ({approx} 6 x L{sub *}) and shows indications of massive recent star formation, perhaps as high as 160 h{sup -1} M{sub {circle_dot}} yr{sup -1}.

  9. VizieR Online Data Catalog: XMM-Newton Serendipitous Source Catalogue 3XMM-DR5 (XMM-SSC, 2016)

    NASA Astrophysics Data System (ADS)

    Rosen, S. R.; Webb, N. A.; Watson; M. G.; Ballet, J.; Barret, D.; Braito, V.; Carrera, F. J.; Ceballos, M. T.; Coriat, M.; Della Ceca, R.; Denkinson, G.; Esquej, P.; Farrell, S. A.; Freyberg, M.; Grise, F.; Guillout, P.; Heil, L.; Law-Green, D.; Lamer, G.; Lin, D.; Martino, R.; Michel, L.; Motch, C.; Nebot Gomez-Moran, A.; Page, C. G.; Page, K.; Page, M.; Pakull, M. W.; Pye, J.; Read, A.; Rodriguez, P.; Sakano, M.; Saxton, R.; Schwope, A.; Scott, A. E.; Sturm, R.; Traulsen, I.; Yershov, V.; Zolotukhin, I.

    2016-02-01

    The 3XMM-DR5 catalogue is the third generation catalog of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory, and has been created by the XMM-Newton Survey Science Centre (SSC) on behalf of ESA. The catalog has 354 more observations and 34701 more detections than the preceding 3XMM-DR4 catalog, which was made public in July 2013. The history of the versions can be summarized as: ---------------------------------------------------- Name DR# Designation Year Cat. #Sources ---------------------------------------------------- 2XMMp 0 2XMMp-DR0 2006 2XMM 1 2XMM-DR1 2007 IX/39 191870 2XMMi 2 2XMMi-DR2 2008 IX/40 221012 2XMMi-DR3 3 2XMMi-DR3 2010 IX/41 262902 3XMM-DR4 4 3XMM 2013 IX/44 372728 3XMM-DR5 5 3XMM 2016 IX/46 396910 ---------------------------------------------------- The production and content of the 3XMM catalogue is described in the the 3XMM-DR4 User Guide at http://xmmssc.irap.omp.eu/Catalogue/3XMM-DR5/3XMM-DR5CatalogueUser_Guide.html The "slim" version of the catalogue (file "xmm3r5s.dat") contains one row per unique source, while the the main catalogue has one row per detection. This slim version includes 44 columns, essentially those containing information about the unique sources, while the full catalogue (file "xmm3r5.fit") describes all detections with 323 columns. The slim version also contains a column with links to the summary pages in the IRAP catalogue archive. In the case of sources with multiple detections the summary page of the best detection is selected (i.e., the detection with the largest exposure time, summed over all cameras), and the summary page gives cross-links to the other detections. A separate file "summary.dat" contains the key details about the observations used in the construction of the 3XMM-DR5 catalogue. (3 data files).

  10. Serendipitous discovery of peritoneal mesothelioma

    PubMed Central

    Jaster, Adam

    2016-01-01

    We present the case of a 64-year-old patient with a history of Birt-Hogg-Dube syndrome, polycystic kidney disease treated with renal transplantation in May 2013, and multiple types of skin cancers, including malignant melanoma. He presented for lymphoscintigraphy for sentinel lymph node identification of the melanoma. Subsequent biopsy of the right axillary sentinel lymph node yielded a diagnosis of epithelial type malignant mesothelioma without a known primary tumor. Follow-up positron emission tomography with 2-deoxy-2-(fluorine-18)fluoro-D-glucose integrated with computed tomography (F-18 FDG PET/CT) demonstrated several suspicious hypermetabolic abdominal masses that were later confirmed to be epithelial-type mesothelioma via percutaneous biopsy. PMID:27034564

  11. Hybrid microelectronic technology

    NASA Astrophysics Data System (ADS)

    Moran, P.

    Various areas of hybrid microelectronic technology are discussed. The topics addressed include: basic thick film processing, thick film pastes and substrates, add-on components and attachment methods, thin film processing, and design of thick film hybrid circuits. Also considered are: packaging hybrid circuits, automating the production of hybrid circuits, application of hybrid techniques, customer's view of hybrid technology, and quality control and assurance in hybrid circuit production.

  12. Hybrid Gear

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  13. ) Hybrid Composite

    NASA Astrophysics Data System (ADS)

    Show, Bijay Kumar; Mondal, Dipak Kumar; Maity, Joydeep

    2014-12-01

    In this research work, the dry sliding wear behavior of 6351 Al-(4 vol.% SiC + 4 vol.% Al2O3) hybrid composite was investigated at low sliding speed (1 m/s) against a hardened EN 31 disk at different loads. In general, the wear mechanism involved adhesion (along with associated subsurface cracking and delamination) and microcutting abrasion at lower load. While at higher load, abrasive wear involving microcutting and microploughing along with adherent oxide formation was observed. The overall wear rate increased with increasing normal load. The massive particle clusters as well as individual reinforcement particles were found to stand tall to resist abrasive wear. Besides, at higher load, the generation of adherent nodular tribo-oxide through nucleation and epitaxial growth on existing Al2O3 particles lowered down the wear rate. Accordingly, at any normal load, 6351 Al-(4 vol.% SiC + 4 vol.% Al2O3) hybrid composite exhibited superior wear resistance (lower overall wear rate) than the reported wear resistance of monolithic 6351 Al alloy.

  14. Hybrid Simulator

    Energy Science and Technology Software Center (ESTSC)

    2005-10-15

    HybSim (short for Hybrid Simulator) is a flexible, easy to use screening tool that allows the user to quanti the technical and economic benefits of installing a village hybrid generating system and simulates systems with any combination of —Diesel generator sets —Photovoltaic arrays -Wind Turbines and -Battery energy storage systems Most village systems (or small population sites such as villages, remote military bases, small communities, independent or isolated buildings or centers) depend on diesel generationmore » systems for their source of energy. HybSim allows the user to determine other "sources" of energy that can greatly reduce the dollar to kilo-watt hour ratio. Supported by the DOE, Energy Storage Program, HybSim was initially developed to help analyze the benefits of energy storage systems in Alaskan villages. Soon after its development, other sources of energy were added providing the user with a greater range of analysis opportunities and providing the village with potentially added savings. In addition to village systems, HybSim has generated interest for use from military institutions in energy provisions and USAID for international village analysis.« less

  15. Hybridized tetraquarks

    NASA Astrophysics Data System (ADS)

    Esposito, A.; Pilloni, A.; Polosa, A. D.

    2016-07-01

    We propose a new interpretation of the neutral and charged X , Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules but rather a manifestation of the interplay between the two. While meson molecules need a negative or zero binding energy, its counterpart for h-tetraquarks is required to be positive. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs0 π± channel by the D0 Collaboration and the negative result presented subsequently by the LHCb Collaboration are understood in this scheme, together with a considerable portion of available data on X , Z particles. Considerations on a state with the same quantum numbers as the X (5568) are also made.

  16. The Wildlife in Your Backyard.

    ERIC Educational Resources Information Center

    VanDruff, Larry

    1979-01-01

    Urban environments often provide wildlife habitat. In addition to such open areas as parks and cemeteries, and such natural areas as may exist along rivers and streams, manmade structures may approximate habitat sought by some species and may attract wildlife. Actions to attract wildlife in the urban setting are suggested. (RE)

  17. Attracting Birds to Your Backyard.

    ERIC Educational Resources Information Center

    Joyce, Brian

    1994-01-01

    Discusses methods for drawing birds to outdoor education areas, including the use of wild and native vegetation. Lists specific garden plants suitable for attracting birds in each season. Includes a guide to commercial bird seed and instructions for building homemade birdfeeders and nestboxes. (LZ)

  18. Starting in Your Own Backyard

    ERIC Educational Resources Information Center

    Adams, Jane

    2006-01-01

    Kilkhampton Junior and Infants School is a rural primary school of 83 children aged 4-11 years, situated on the Atlantic Highway (A39) just inside Cornwall and close to the coast, beaches and walks. In this article, the author describes the school's work beyond the classroom as part of the National Trust Guardianship Scheme.

  19. Backyard Astronomy: Observing Moon Phases.

    ERIC Educational Resources Information Center

    Brandou, Bob

    1997-01-01

    Presents an activity involving the observation of moon phases that can provide a one-on-one learning experience and stimulate interaction between a child and an adult family member. This activity can also be initiated by teachers and outcomes can be integrated into the classroom science curriculum. (JRH)

  20. Invite Wildlife to Your Backyard

    ERIC Educational Resources Information Center

    Thomas, Jack Ward; And Others

    1973-01-01

    A step-by-step plan to create a wildlife habitat around one's home is depicted. Three stages, covering 30 to 40 years from initial planting, will provide food, water, cover, and reproductive areas for a large variety of plant and animal life. (BL)

  1. The limitations of a feed/water based heat-stable vaccine delivery system forNnewcastle disease-control strategies for backyard poultry flocks in sub-Saharan Africa.

    PubMed

    Oakeley, R D

    2000-12-01

    Backyard poultry are a major contributor to egg and meat consumption in sub-Saharan Africa and an important source of income for many rural producers. Production throughout Africa is severely constrained by continuing outbreaks of Newcastle disease. The livestock-service sector lacks the resources and infrastructure to control Newcastle disease in extensive flocks without the active participation of producers. The development of 'heat-stable' Newcastle disease vaccines offers a potential solution. Trials over the last two decades have examined the effectiveness of heat-stable vaccines in both controlling Newcastle disease and in involving the rural community in control strategies. Constraints highlighted include the reliability of the vaccines using alternative delivery methods and the capacity of rural communities to apply those methods. The search for appropriate Newcastle disease-control strategies in extensive poultry systems should focus on policies and methodologies that incorporate the wider concerns and priorities of extensive producers. PMID:11087958

  2. Hybrid mimics and hybrid vigor in Arabidopsis

    PubMed Central

    Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

    2015-01-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378

  3. Hybrid rocket propulsion

    NASA Technical Reports Server (NTRS)

    Holzman, Allen L.

    1993-01-01

    Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

  4. Hybridization and hybrid speciation under global change.

    PubMed

    Vallejo-Marín, Mario; Hiscock, Simon J

    2016-09-01

    Contents 1170 I. 1170 II. 1172 III. 1175 IV. 1180 V. 1183 1184 References 1184 SUMMARY: An unintended consequence of global change is an increase in opportunities for hybridization among previously isolated lineages. Here we illustrate how global change can facilitate the breakdown of reproductive barriers and the formation of hybrids, drawing on the flora of the British Isles for insight. Although global change may ameliorate some of the barriers preventing hybrid establishment, for example by providing new ecological niches for hybrids, it will have limited effects on environment-independent post-zygotic barriers. For example, genic incompatibilities and differences in chromosome numbers and structure within hybrid genomes are unlikely to be affected by global change. We thus speculate that global change will have a larger effect on eroding pre-zygotic barriers (eco-geographical isolation and phenology) than post-zygotic barriers, shifting the relative importance of these two classes of reproductive barriers from what is usually seen in naturally produced hybrids where pre-zygotic barriers are the largest contributors to reproductive isolation. Although the long-term fate of neo-hybrids is still to be determined, the massive impact of global change on the dynamics and distribution of biodiversity generates an unprecedented opportunity to study large numbers of unpredicted, and often replicated, hybridization 'experiments', allowing us to peer into the birth and death of evolutionary lineages. PMID:27214560

  5. From hybrid swarms to swarms of hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The introgression of modern humans (Homo sapiens) with Neanderthals 40,000 YBP after a half-million years of separation, may have led to the best example of a hybrid swarm on earth. Modern trade and transportation in support of the human hybrids has continued to introduce additional species, genotyp...

  6. Mesoscale hybrid calibration artifact

    DOEpatents

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  7. Homoploid hybrid expectations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Homoploid hybrid speciation occurs when a stable, fertile, and reproductively isolated lineage results from hybridization between two distinct species without a change in ploidy level. Reproductive isolation between a homoploid hybrid species and its parents is generally attained via chromosomal re...

  8. Hybrid quantum information processing

    SciTech Connect

    Furusawa, Akira

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  9. Hybrid rocket instability

    NASA Technical Reports Server (NTRS)

    Greiner, B.; Frederick, R. A., Jr.

    1993-01-01

    The paper provides a brief review of theoretical and experimental studies concerned with hybrid rocket instability. The instabilities discussed include atomization and mixing instabilities, chuffing instabilities, pressure coupled combustion instabilities, and vortex shedding. It is emphasized that the future use of hybrid motor systems as viable design alternatives will depend on a better understanding of hybrid instability.

  10. Hybrid rocket instability

    NASA Astrophysics Data System (ADS)

    Greiner, B.; Frederick, R. A., Jr.

    1993-06-01

    The paper provides a brief review of theoretical and experimental studies concerned with hybrid rocket instability. The instabilities discussed include atomization and mixing instabilities, chuffing instabilities, pressure coupled combustion instabilities, and vortex shedding. It is emphasized that the future use of hybrid motor systems as viable design alternatives will depend on a better understanding of hybrid instability.

  11. Hybrid armature projectile

    DOEpatents

    Hawke, R.S.; Asay, J.R.; Hall, C.A.; Konrad, C.H.; Sauve, G.L.; Shahinpoor, M.; Susoeff, A.R.

    1993-03-02

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasma blowby.

  12. Hybrid armature projectile

    DOEpatents

    Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

    1993-01-01

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

  13. Hybridization and extinction.

    PubMed

    Todesco, Marco; Pascual, Mariana A; Owens, Gregory L; Ostevik, Katherine L; Moyers, Brook T; Hübner, Sariel; Heredia, Sylvia M; Hahn, Min A; Caseys, Celine; Bock, Dan G; Rieseberg, Loren H

    2016-08-01

    Hybridization may drive rare taxa to extinction through genetic swamping, where the rare form is replaced by hybrids, or by demographic swamping, where population growth rates are reduced due to the wasteful production of maladaptive hybrids. Conversely, hybridization may rescue the viability of small, inbred populations. Understanding the factors that contribute to destructive versus constructive outcomes of hybridization is key to managing conservation concerns. Here, we survey the literature for studies of hybridization and extinction to identify the ecological, evolutionary, and genetic factors that critically affect extinction risk through hybridization. We find that while extinction risk is highly situation dependent, genetic swamping is much more frequent than demographic swamping. In addition, human involvement is associated with increased risk and high reproductive isolation with reduced risk. Although climate change is predicted to increase the risk of hybridization-induced extinction, we find little empirical support for this prediction. Similarly, theoretical and experimental studies imply that genetic rescue through hybridization may be equally or more probable than demographic swamping, but our literature survey failed to support this claim. We conclude that halting the introduction of hybridization-prone exotics and restoring mature and diverse habitats that are resistant to hybrid establishment should be management priorities. PMID:27468307

  14. An epidemiologic simulation model of the spread and control of highly pathogenic avian influenza (H5N1) among commercial and backyard poultry flocks in South Carolina, United States.

    PubMed

    Patyk, Kelly A; Helm, Julie; Martin, Michael K; Forde-Folle, Kimberly N; Olea-Popelka, Francisco J; Hokanson, John E; Fingerlin, Tasha; Reeves, Aaron

    2013-07-01

    Epidemiologic simulation modeling of highly pathogenic avian influenza (HPAI) outbreaks provides a useful conceptual framework with which to estimate the consequences of HPAI outbreaks and to evaluate disease control strategies. The purposes of this study were to establish detailed and informed input parameters for an epidemiologic simulation model of the H5N1 strain of HPAI among commercial and backyard poultry in the state of South Carolina in the United States using a highly realistic representation of this poultry population; to estimate the consequences of an outbreak of HPAI in this population with a model constructed from these parameters; and to briefly evaluate the sensitivity of model outcomes to several parameters. Parameters describing disease state durations; disease transmission via direct contact, indirect contact, and local-area spread; and disease detection, surveillance, and control were established through consultation with subject matter experts, a review of the current literature, and the use of several computational tools. The stochastic model constructed from these parameters produced simulated outbreaks ranging from 2 to 111 days in duration (median 25 days), during which 1 to 514 flocks were infected (median 28 flocks). Model results were particularly sensitive to the rate of indirect contact that occurs among flocks. The baseline model established in this study can be used in the future to evaluate various control strategies, as a tool for emergency preparedness and response planning, and to assess the costs associated with disease control and the economic consequences of a disease outbreak. PMID:23398856

  15. Hybrid radiator cooling system

    DOEpatents

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  16. Managing hybrid marketing systems.

    PubMed

    Moriarty, R T; Moran, U

    1990-01-01

    As competition increases and costs become critical, companies that once went to market only one way are adding new channels and using new methods - creating hybrid marketing systems. These hybrid marketing systems hold the promise of greater coverage and reduced costs. But they are also hard to manage; they inevitably raise questions of conflict and control: conflict because marketing units compete for customers; control because new indirect channels are less subject to management authority. Hard as they are to manage, however, hybrid marketing systems promise to become the dominant design, replacing the "purebred" channel strategy in all kinds of businesses. The trick to managing the hybrid is to analyze tasks and channels within and across a marketing system. A map - the hybrid grid - can help managers make sense of their hybrid system. What the chart reveals is that channels are not the basic building blocks of a marketing system; marketing tasks are. The hybrid grid forces managers to consider various combinations of channels and tasks that will optimize both cost and coverage. Managing conflict is also an important element of a successful hybrid system. Managers should first acknowledge the inevitability of conflict. Then they should move to bound it by creating guidelines that spell out which customers to serve through which methods. Finally, a marketing and sales productivity (MSP) system, consisting of a central marketing database, can act as the central nervous system of a hybrid marketing system, helping managers create customized channels and service for specific customer segments. PMID:10107959

  17. Hybridization facilitates evolutionary rescue

    PubMed Central

    Stelkens, Rike B; Brockhurst, Michael A; Hurst, Gregory D D; Greig, Duncan

    2014-01-01

    The resilience of populations to rapid environmental degradation is a major concern for biodiversity conservation. When environments deteriorate to lethal levels, species must evolve to adapt to the new conditions to avoid extinction. Here, we test the hypothesis that evolutionary rescue may be enabled by hybridization, because hybridization increases genetic variability. Using experimental evolution, we show that interspecific hybrid populations of Saccharomyces yeast adapt to grow in more highly degraded environments than intraspecific and parental crosses, resulting in survival rates far exceeding those of their ancestors. We conclude that hybridization can increase evolutionary responsiveness and that taxa able to exchange genes with distant relatives may better survive rapid environmental change. PMID:25558281

  18. From hybrid swarms to swarms of hybrids

    USGS Publications Warehouse

    Stohlgren, Thomas J.; Szalanski, Allen L; Gaskin, John F.; Young, Nicholas E.; West, Amanda; Jarnevich, Catherine S.; Tripodi, Amber

    2015-01-01

    Science has shown that the introgression or hybridization of modern humans (Homo sapiens) with Neanderthals up to 40,000 YBP may have led to the swarm of modern humans on earth. However, there is little doubt that modern trade and transportation in support of the humans has continued to introduce additional species, genotypes, and hybrids to every country on the globe. We assessed the utility of species distributions modeling of genotypes to assess the risk of current and future invaders. We evaluated 93 locations of the genus Tamarix for which genetic data were available. Maxent models of habitat suitability showed that the hybrid, T. ramosissima x T. chinensis, was slightly greater than the parent taxa (AUCs > 0.83). General linear models of Africanized honey bees, a hybrid cross of Tanzanian Apis mellifera scutellata and a variety of European honey bee including A. m. ligustica, showed that the Africanized bees (AUC = 0.81) may be displacing European honey bees (AUC > 0.76) over large areas of the southwestern U.S. More important, Maxent modeling of sub-populations (A1 and A26 mitotypes based on mDNA) could be accurately modeled (AUC > 0.9), and they responded differently to environmental drivers. This suggests that rapid evolutionary change may be underway in the Africanized bees, allowing the bees to spread into new areas and extending their total range. Protecting native species and ecosystems may benefit from risk maps of harmful invasive species, hybrids, and genotypes.

  19. Hybrid baryons [alpha].

    SciTech Connect

    Page, P. R.

    2002-01-01

    The authors review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modeled by both the bag and flux tube models. The low lying hybrid baryon is N 1/2{sup +} with a mass of 1.5 - 1.8 GeV. Hybrid baryons can be produced in the glue rich processes of diffractive {gamma}N and {pi}N production, {Psi} decays and p{bar p} annihilation. We review the current status of research on three quarks with a gluonic excitation, called a hybrid baryon. The excitation is not an orbital or radial excitation between the quarks. Hybrid baryons have also been reviewed elsewhere. The Mercedes-Benz logl in Figure 1 indicates two possible views of the confining interaction of three quarks, an essential issue in the study of hybrid baryons. In the logo the three points where the Y shape meets the boundary circle should be identified with the three quarks. There are two possibilities fo rthe interaction of the quarks: (1) a pairwise interaction of the quarks represented by the circle, or (2) a Y shaped interaction between the quarks, represented by the Y-shape in the logo.

  20. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A 10,000-pound thrust hybrid rocket motor is tested at Stennis Space Center's E-1 test facility. A hybrid rocket motor is a cross between a solid rocket and a liquid-fueled engine. It uses environmentally safe solid fuel and liquid oxygen.

  1. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  2. Hybrid rocket performance

    NASA Astrophysics Data System (ADS)

    Frederick, Robert A., Jr.

    1992-12-01

    A hybrid rocket is a system consisting of a solid fuel grain and a gaseous or liquid oxidizer. Figure 1 shows three popular hybrid propulsion cycles that are under current consideration. NASA MSFC has teamed with industry to test two hybrid propulsion systems that will allow scaling to motors of potential interest for Titan and Atlas systems, as well as encompassing the range of interest for SEI lunar ascent stages and National Launch System Cargo Transfer Vehicle (NLS CTV) and NLS deorbit systems. Hybrid systems also offer advantages as moderate-cost, environmentally acceptable propulsion system. The objective of this work was to recommend a performance prediction methodology for hybrid rocket motors. The scope included completion of: a literature review, a general methodology, and a simplified performance model.

  3. Hybrid rocket performance

    NASA Technical Reports Server (NTRS)

    Frederick, Robert A., Jr.

    1992-01-01

    A hybrid rocket is a system consisting of a solid fuel grain and a gaseous or liquid oxidizer. Figure 1 shows three popular hybrid propulsion cycles that are under current consideration. NASA MSFC has teamed with industry to test two hybrid propulsion systems that will allow scaling to motors of potential interest for Titan and Atlas systems, as well as encompassing the range of interest for SEI lunar ascent stages and National Launch System Cargo Transfer Vehicle (NLS CTV) and NLS deorbit systems. Hybrid systems also offer advantages as moderate-cost, environmentally acceptable propulsion system. The objective of this work was to recommend a performance prediction methodology for hybrid rocket motors. The scope included completion of: a literature review, a general methodology, and a simplified performance model.

  4. Hybrid baryons in QCD

    SciTech Connect

    Dudek, Jozef J.; Edwards, Robert G.

    2012-03-21

    In this study, we present the first comprehensive study of hybrid baryons using lattice QCD methods. Using a large basis of composite QCD interpolating fields we extract an extensive spectrum of baryon states and isolate those of hybrid character using their relatively large overlap onto operators which sample gluonic excitations. We consider the spectrum of Nucleon and Delta states at several quark masses finding a set of positive parity hybrid baryons with quantum numbers $N_{1/2^+},\\,N_{1/2^+},\\,N_{3/2^+},\\, N_{3/2^+},\\,N_{5/2^+},\\,$ and $\\Delta_{1/2^+},\\, \\Delta_{3/2^+}$ at an energy scale above the first band of `conventional' excited positive parity baryons. This pattern of states is compatible with a color octet gluonic excitation having $J^{P}=1^{+}$ as previously reported in the hybrid meson sector and with a comparable energy scale for the excitation, suggesting a common bound-state construction for hybrid mesons and baryons.

  5. Hybrid propulsion technology program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  6. Hybrid vigour in dogs?

    PubMed

    Nicholas, Frank W; Arnott, Elizabeth R; McGreevy, Paul D

    2016-08-01

    Evidence from other species justifies the hypotheses that useful hybrid vigour occurs in dogs and that it can be exploited for improved health, welfare and fitness for purpose. Unfortunately, most of the relevant published canine studies do not provide estimates of actual hybrid vigour because of inadequate specification of the parentage of mixed-bred dogs. To our knowledge, only three published studies have shed any light on actual hybrid vigour in dogs. There are two reports of actual hybrid vigour between Labrador and Golden retrievers, the first ranging from +2.5% to -6.0% for components of a standardised applied-stimulus behavioural test, and the second being at least +12.4% for chance of graduating as a guide dog. The third study provides a minimum estimate of negative actual hybrid vigour: crossbreds between Labrador retrievers and poodles had a higher prevalence of multifocal retinal dysplasia than the average prevalence in their purebred parent breeds. The lack of estimates of actual hybrid vigour can be overcome by including the exact nature of the cross (e.g. F1, F2 or backcross) and their purebred parental breeds in the specification of mixed-bred dogs. Even if only F1 crossbreds can be categorised, this change would enable researchers to conduct substantial investigations to determine whether hybrid vigour has any utility for dog breeding. PMID:27387730

  7. Functional Hybrid Materials

    NASA Astrophysics Data System (ADS)

    Gómez-Romero, Pedro; Sanchez, Clément

    2004-04-01

    Functional Hybrid Materials consist of both organic and inorganic components, assembled for the purpose of generating desirable properties and functionalities. The aim is twofold: to bring out or enhance advantageous chemical, electrochemical, magnetic or electronic characteristics and at the same time to reduce or wholly suppress undesirable properties or effects. Another target is the creation of entirely new material behavior. The vast number of hybrid material components available has opened up a wide and diversified field of fascinating research. In this book, a team of highly renowned experts gives an in-depth overview, illustrating the superiority of well-designed hybrid materials and their potential applications.

  8. Hybrid matrix fiber composites

    DOEpatents

    Deteresa, Steven J.; Lyon, Richard E.; Groves, Scott E.

    2003-07-15

    Hybrid matrix fiber composites having enhanced compressive performance as well as enhanced stiffness, toughness and durability suitable for compression-critical applications. The methods for producing the fiber composites using matrix hybridization. The hybrid matrix fiber composites include two chemically or physically bonded matrix materials, whereas the first matrix materials are used to impregnate multi-filament fibers formed into ribbons and the second matrix material is placed around and between the fiber ribbons that are impregnated with the first matrix material and both matrix materials are cured and solidified.

  9. Artificial mismatch hybridization

    DOEpatents

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  10. Hybrid electric vehicles TOPTEC

    SciTech Connect

    1994-06-21

    This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.

  11. Towers of hybrid mesons

    SciTech Connect

    Semay, Claude; Buisseret, Fabien; Silvestre-Brac, Bernard

    2009-05-01

    A hybrid meson is a quark-antiquark pair in which, contrary to ordinary mesons, the gluon field is in an excited state. In the framework of constituent models, the interaction potential is assumed to be the energy of an excited string. An approximate, but accurate, analytical solution of the Schroedinger equation with such a potential is presented. When applied to hybrid charmonia and bottomonia, towers of states are predicted in which the masses are a linear function of a harmonic oscillator band number for the quark-antiquark pair. Such a formula could be a reliable guide for the experimental detection of heavy hybrid mesons.

  12. Hybrid Rocket Motor Test

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Stennis Space Center conducts a test on a hybrid rocket motor fed by a liquid oxygen turbopump. The test occurred at the E-1 test facility. The test was believed to be the first of its kind in the world.

  13. Hybrid rocket combustion study

    NASA Astrophysics Data System (ADS)

    Strand, L. D.; Ray, R. L.; Cohen, N. S.

    1993-06-01

    The objectives of this study of 'pure' or 'classic' hybrids are to (1) extend our understanding of the boundary layer combustion process and the critical engineering parameters that define this process, (2) develop an up-to-date hybrid fuel combustion model, and (3) apply the model to correlate the regression rate and scaling properties of potential fuel candidates. Tests were carried out with a hybrid slab window motor, using several diagnostic techniques, over a range of motor pressure and oxidizer mass flux conditions. The results basically confirmed turbulent boundary layer heat and mass transfer as the rate limiting process for hybrid fuel decomposition and combustion. The measured fuel regression rates showed good agreement with the analytical model predictions. The results of model scaling calculations to Shuttle SRM size conditions are presented.

  14. Hybrid adsorptive membrane reactor

    DOEpatents

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  15. Hybrid rocket combustion study

    NASA Technical Reports Server (NTRS)

    Strand, L. D.; Ray, R. L.; Cohen, N. S.

    1993-01-01

    The objectives of this study of 'pure' or 'classic' hybrids are to (1) extend our understanding of the boundary layer combustion process and the critical engineering parameters that define this process, (2) develop an up-to-date hybrid fuel combustion model, and (3) apply the model to correlate the regression rate and scaling properties of potential fuel candidates. Tests were carried out with a hybrid slab window motor, using several diagnostic techniques, over a range of motor pressure and oxidizer mass flux conditions. The results basically confirmed turbulent boundary layer heat and mass transfer as the rate limiting process for hybrid fuel decomposition and combustion. The measured fuel regression rates showed good agreement with the analytical model predictions. The results of model scaling calculations to Shuttle SRM size conditions are presented.

  16. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  17. Plum and plum hybrids.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-six plum and plum hybrid cultivars are briefly described for the Fruit and Nut Register 45. This register is made to keep the plum industry and researchers up to date on the latest cultivars released....

  18. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  19. Hybrid image processing

    NASA Technical Reports Server (NTRS)

    Juday, Richard D.

    1990-01-01

    Partly-digital, partly-optical 'hybrid' image processing attempts to use the properties of each domain to synergistic advantage: while Fourier optics furnishes speed, digital processing allows the use of much greater algorithmic complexity. The video-rate image-coordinate transformation used is a critical technology for real-time hybrid image-pattern recognition. Attention is given to the separation of pose variables, image registration, and both single- and multiple-frame registration.

  20. Systems for hybrid cars

    NASA Astrophysics Data System (ADS)

    Bitsche, Otmar; Gutmann, Guenter

    Not only sharp competition but also legislation are pushing development of hybrid drive trains. Based on conventional internal combustion engine (ICE) vehicles, these drive trains offer a wide range of benefits from reduced fuel consumption and emission to multifaceted performance improvements. Hybrid electric drive trains may also facilitate the introduction of fuel cells (FC). The battery is the key component for all hybrid drive trains, as it dominates cost and performance issues. The selection of the right battery technology for the specific automotive application is an important task with an impact on costs of development and use. Safety, power, and high cycle life are a must for all hybrid applications. The greatest pressure to reduce cost is in soft hybrids, where lead-acid embedded in a considerate management presents the cheapest solution, with a considerable improvement in performance needed. From mild to full hybridization, an improvement in specific power makes higher costs more acceptable, provided that the battery's service life is equivalent to the vehicle's lifetime. Today, this is proven for the nickel-metal hydride system. Lithium ion batteries, which make use of a multiple safety concept, and with some development anticipated, provide even better prospects in terms of performance and costs. Also, their scalability permits their application in battery electric vehicles—the basis for better performance and enhanced user acceptance. Development targets for the batteries are discussed with a focus on system aspects such as electrical and thermal management and safety.

  1. Serendipitous discoveries in nonlocal gravity theory

    NASA Astrophysics Data System (ADS)

    Barvinsky, A. O.

    2012-05-01

    We present a class of generally covariant nonlocal gravity models which have a flat-space general relativistic limit and also possess a stable de Sitter or anti-de Sitter (AdS) background with an arbitrary value of its cosmological constant. The nonlocal action of the theory is formulated in the Euclidean signature spacetime and is understood as an approximation to the quantum effective action (generating functional of one-particle irreducible diagrams) originating from fundamental quantum gravity theory. Using the known relation between the Schwinger-Keldysh technique for quantum expectation values and the Euclidean quantum field theory we derive from this action the causal effective equations of motion for mean value of the metric field in the physical Lorentzian-signature spacetime. Thus we show that the (A)dS background of the theory carries as free propagating modes massless gravitons having two polarizations identical to those of the Einstein theory with a cosmological term. The on-shell action of the theory is vanishing both for the flat-space and (A)dS backgrounds which play the role of stable vacua underlying, respectively, the ultraviolet and infrared phases of the theory. We also obtain linearized gravitational potentials of compact matter sources and show that in the infrared (A)dS phase their effective gravitational coupling Geff can be essentially different from the Newton gravitational constant GN of the short-distance general relativistic phase. When Geff≫GN the (A)dS phase can be regarded as a strongly coupled infrared modification of Einstein theory not only describing the dark energy mechanism of cosmic acceleration but also simulating the dark matter phenomenon by enhanced gravitational attraction at long distances.

  2. Serendipitous SEU hardening of resistive load SRAMs

    SciTech Connect

    Koga, R.; Kirshman, J.F.; Pinkerton, S.D.; Hansel, S.J.; Crawford, K.B.; Crain, W.R.

    1996-06-01

    High and low resistive load versions of Micron Technology`s MT5C1008C (128K {times} 8) and MT5C2561C (256K {times} 1) SRAMs were tested for SEU vulnerability. Contrary to computer simulation results, SEU susceptibility decreased with increasing resistive load. A substantially larger number of multiple-bit errors were observed for the low resistive load SRAMs, which also exhibited a 1 {r_arrow} 0 to 0 {r_arrow} 1 bit error ratio close to unity; in contrast, the high resistive load devices displayed a pronounced error bit polarity effect. Two distinct upset mechanisms are proposed to account for these observations.

  3. The BMW-Chandra Serendipitous Source Catalogue

    NASA Astrophysics Data System (ADS)

    Romano, P.; Campana, S.; Mignani, R. P.; Moretti, A.; Panzera, M. R.; Tagliaferri, G.

    We present the BMW-Chandra Source Catalogue drawn from all Chandra ACIS-I pointed observations with an exposure time in excess of 10 ks public as of March 2003 (136 observations). Using the wavelet detection algorithm developed by \\citep{Lazzatiea99} and \\citep{Campanaea99}, which can characterize point-like as well as extended sources, we identified 21325 sources which were visually inspected and verified. Among them, 16758 are not associated with the targets of the pointings and are considered certain; they have a 0.5-10 keV absorption corrected flux distribution median of ˜ 7 × 10-15 erg cm-2 s-1. The catalogue consists of source positions, count rates, extensions and relative errors in three energy bands (total, 0.5-7 keV; soft, 0.5-2 keV; and hard band, 2-7 keV), as well as the additional information drawn from the headers of the original files. We also extracted source counts in four additional energy bands, (0.5-1.0 keV, 1.0-2.0 keV, 2.0-4.0 keV and 4.0-7.0 keV). We compute the sky coverage in the soft and hard bands. The complete catalogue provides a sky coverage in the soft band (0.5-2 keV, S/N =3) of ˜ 8 deg2 at a limiting flux of ˜ 10-13 erg cm-2 s-1, and ˜ 2 deg2 at a limiting flux of ˜ 10-15 erg cm-2 s-1. http://www.merate.mi.astro.it/~xanadu/BMC/bmc_home.html

  4. Hybrid Propulsion Demonstration Program 250K Hybrid Motor

    NASA Technical Reports Server (NTRS)

    Story, George; Zoladz, Tom; Arves, Joe; Kearney, Darren; Abel, Terry; Park, O.

    2003-01-01

    The Hybrid Propulsion Demonstration Program (HPDP) program was formed to mature hybrid propulsion technology to a readiness level sufficient to enable commercialization for various space launch applications. The goal of the HPDP was to develop and test a 250,000 pound vacuum thrust hybrid booster in order to demonstrate hybrid propulsion technology and enable manufacturing of large hybrid boosters for current and future space launch vehicles. The HPDP has successfully conducted four tests of the 250,000 pound thrust hybrid rocket motor at NASA's Stennis Space Center. This paper documents the test series.

  5. Hybrid baryons in QCD

    DOE PAGESBeta

    Dudek, Jozef J.; Edwards, Robert G.

    2012-03-21

    In this study, we present the first comprehensive study of hybrid baryons using lattice QCD methods. Using a large basis of composite QCD interpolating fields we extract an extensive spectrum of baryon states and isolate those of hybrid character using their relatively large overlap onto operators which sample gluonic excitations. We consider the spectrum of Nucleon and Delta states at several quark masses finding a set of positive parity hybrid baryons with quantum numbersmore » $$N_{1/2^+},\\,N_{1/2^+},\\,N_{3/2^+},\\, N_{3/2^+},\\,N_{5/2^+},\\,$$ and $$\\Delta_{1/2^+},\\, \\Delta_{3/2^+}$$ at an energy scale above the first band of `conventional' excited positive parity baryons. This pattern of states is compatible with a color octet gluonic excitation having $$J^{P}=1^{+}$$ as previously reported in the hybrid meson sector and with a comparable energy scale for the excitation, suggesting a common bound-state construction for hybrid mesons and baryons.« less

  6. Research on Hybrid Vehicle Drivetrain

    NASA Astrophysics Data System (ADS)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  7. Hybridization schemes for clusters

    NASA Astrophysics Data System (ADS)

    Wales, David J.

    The concept of an optimum hybridization scheme for cluster compounds is developed with particular reference to electron counting. The prediction of electron counts for clusters and the interpretation of the bonding is shown to depend critically upon the presumed hybridization pattern of the cluster vertex atoms. This fact has not been properly appreciated in previous work, particularly in applications of Stone's tensor surface harmonic (TSH) theory, but is found to be a useful tool when dealt with directly. A quantitative definition is suggested for the optimum cluster hybridization pattern based directly upon the ease of interpretation of the molecular orbitals, and results are given for a range of species. The relationship of this scheme to the detailed cluster geometry is described using Löwdin's partitioned perturbation theory, and the success and range of application of TSH theory are discussed.

  8. Ames Hybrid Combustion Facility

    NASA Technical Reports Server (NTRS)

    Zilliac, Greg; Karabeyoglu, Mustafa A.; Cantwell, Brian; Hunt, Rusty; DeZilwa, Shane; Shoffstall, Mike; Soderman, Paul T.; Bencze, Daniel P. (Technical Monitor)

    2003-01-01

    The report summarizes the design, fabrication, safety features, environmental impact, and operation of the Ames Hybrid-Fuel Combustion Facility (HCF). The facility is used in conducting research into the scalability and combustion processes of advanced paraffin-based hybrid fuels for the purpose of assessing their applicability to practical rocket systems. The facility was designed to deliver gaseous oxygen at rates between 0.5 and 16.0 kg/sec to a combustion chamber operating at pressures ranging from 300 to 900. The required run times were of the order of 10 to 20 sec. The facility proved to be robust and reliable and has been used to generate a database of regression-rate measurements of paraffin at oxygen mass flux levels comparable to those of moderate-sized hybrid rocket motors.

  9. Hybridization in geese: a review.

    PubMed

    Ottenburghs, Jente; van Hooft, Pim; van Wieren, Sipke E; Ydenberg, Ronald C; Prins, Herbert H T

    2016-01-01

    The high incidence of hybridization in waterfowl (ducks, geese and swans) makes this bird group an excellent study system to answer questions related to the evolution and maintenance of species boundaries. However, knowledge on waterfowl hybridization is biased towards ducks, with a large knowledge gap in geese. In this review, we assemble the available information on hybrid geese by focusing on three main themes: (1) incidence and frequency, (2) behavioural mechanisms leading to hybridization, and (3) hybrid fertility. Hybridization in geese is common on a species-level, but rare on a per-individual level. An overview of the different behavioural mechanisms indicates that forced extra-pair copulations and interspecific nest parasisitm can both lead to hybridization. Other sources of hybrids include hybridization in captivity and vagrant geese, which may both lead to a scarcity of conspecifics. The different mechanisms are not mutually exclusive and it is currently not possible to discriminate between the different mechanisms without quantitative data. Most hybrid geese are fertile; only in crosses between distantly related species do female hybrids become sterile. This fertility pattern, which is in line with Haldane's Rule, may facilitate interspecific gene flow between closely related species. The knowledge on hybrid geese should be used, in combination with the information available on hybridization in ducks, to study the process of avian speciation. PMID:27182276

  10. Smart hybrid rotary damper

    NASA Astrophysics Data System (ADS)

    Yang, C. S. Walter; DesRoches, Reginald

    2014-03-01

    This paper develops a smart hybrid rotary damper using a re-centering smart shape memory alloy (SMA) material as well as conventional energy-dissipating metallic plates that are easy to be replaced. The ends of the SMA and steel plates are inserted in the hinge. When the damper rotates, all the plates bend, providing energy dissipating and recentering characteristics. Such smart hybrid rotary dampers can be installed in structures to mitigate structural responses and to re-center automatically. The damaged energy-dissipating plates can be easily replaced promptly after an external excitation, reducing repair time and costs. An OpenSEES model of a smart hybrid rotary was established and calibrated to reproduce the realistic behavior measured from a full-scale experimental test. Furthermore, the seismic performance of a 3-story moment resisting model building with smart hybrid rotary dampers designed for downtown Los Angeles was also evaluated in the OpenSEES structural analysis software. Such a smart moment resisting frame exhibits perfect residual roof displacement, 0.006", extremely smaller than 18.04" for the conventional moment resisting frame subjected to a 2500 year return period ground motion for the downtown LA area (an amplified factor of 1.15 on Kobe earthquake). The smart hybrid rotary dampers are also applied into an eccentric braced steel frame, which combines a moment frame system and a bracing system. The results illustrate that adding smart hybrid rotaries in this braced system not only completely restores the building after an external excitation, but also significantly reduces peak interstory drifts.

  11. Hybrid nonlocality distillation

    NASA Astrophysics Data System (ADS)

    Wu, Keng-Shuo; Hsu, Li-Yi

    2013-08-01

    In this Letter, we introduce the notion of hybrid nonlocality distillation, in which different nonlocal boxes are exploited for nonlocality distillation. Here, we quantify the nonlocality using the violation degree of either the Clauser-Horne-Shimony-Holt inequality or the I3322 inequality. Our study shows that hybrid nonlocality distillation can outperform nonlocality distillation using copies of single nonlocal boxes. In particular, more nonlocality of undistillable boxes can be activated with the assistance of distillable boxes. Equivalently, distillable boxes can achieve more nonlocality with the assistance of undistillable boxes.

  12. Diagnostics for hybrid reactors

    NASA Astrophysics Data System (ADS)

    Orsitto, Francesco Paolo

    2012-06-01

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  13. Hybridized polymer matrix composite

    NASA Technical Reports Server (NTRS)

    Stern, B. A.; Visser, T.

    1981-01-01

    Under certain conditions of combined fire and impact, graphite fibers are released to the atmosphere by graphite fiber composites. The retention of graphite fibers in these situations is investigated. Hybrid combinations of graphite tape and cloth, glass cloth, and resin additives are studied with resin systems. Polyimide resins form the most resistant composites and resins based on simple novolac epoxies the least resistant of those tested. Great improvement in the containment of the fibers is obtained in using graphite/glass hybrids, and nearly complete prevention of individual fiber release is made possible by the use of resin additives.

  14. Diagnostics for hybrid reactors

    SciTech Connect

    Orsitto, Francesco Paolo

    2012-06-19

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  15. Hybrid network intrusion detection

    NASA Astrophysics Data System (ADS)

    Tahmoush, David

    2014-05-01

    We report on a machine learning classifier that can be used to discover the patterns hidden within large networking data flows. It utilizes an existing intrusion detection system (IDS) as an oracle to learn a faster, less resource intensive normalcy classifier as a front-end to a hybrid network IDS. This system has the capability to recognize new attacks that are similar to known attack signatures. It is also more highly scalable and distributable than the signature-based IDS. The new hybrid design also allows distributed updates and retraining of the normalcy classifier to stay up-to-date with current threats.

  16. A Mathematical Approach to Hybridization

    ERIC Educational Resources Information Center

    Matthews, P. S. C.; Thompson, J. J.

    1975-01-01

    Presents an approach to hybridization which exploits the similarities between the algebra of wave functions and vectors. This method will account satisfactorily for the number of orbitals formed when applied to hybrids involving the s and p orbitals. (GS)

  17. Hybrid polarization control

    NASA Astrophysics Data System (ADS)

    Gray, George R.; Ibragimov, Edem; Sluz, Joseph; Sova, Raymond

    2005-05-01

    We demonstrate a novel method of polarization control that combines rotatable waveplates (angle control) and variable retarders (retardance control). Such a "hybrid" polarization controller performs far better than conventional controllers, allowing nearly perfect arbitrary-to-arbitrary polarization transformations. We show theoretically that the two control parameters augment one another because they tend to result in orthogonal movements on the Poincaré sphere.

  18. Nuclear hybrid energy infrastructure

    SciTech Connect

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  19. Rethinking Resources and Hybridity

    ERIC Educational Resources Information Center

    Gonsalves, Allison J.; Seiler, Gale; Salter, Dana E.

    2011-01-01

    This review explores Alfred Schademan's "What does playing cards have to do with science? A resource-rich view of African American young men" by examining how he uses two key concepts--hybridity and resources--to propose an approach to science education that counters enduring deficit notions associated with this population. Our response to…

  20. Hybrid Imaging in Oncology.

    PubMed

    Fatima, Nosheen; Zaman, Maseeh uz; Gnanasegaran, Gopinath; Zaman, Unaiza; Shahid, Wajeeha; Zaman, Areeba; Tahseen, Rabia

    2015-01-01

    In oncology various imaging modalities play a crucial role in diagnosis, staging, restaging, treatment monitoring and follow up of various cancers. Stand-alone morphological imaging like computerized tomography (CT) and magnetic resonance imaging (MRI) provide a high magnitude of anatomical details about the tumor but are relatively dumb about tumor physiology. Stand-alone functional imaging like positron emission tomography (PET) and single photon emission tomography (SPECT) are rich in functional information but provide little insight into tumor morphology. Introduction of first hybrid modality PET/CT is the one of the most successful stories of current century which has revolutionized patient care in oncology due to its high diagnostic accuracy. Spurred on by this success, more hybrid imaging modalities like SPECT/CT and PET/MR were introduced. It is the time to explore the potential applications of the existing hybrid modalities, developing and implementing standardized imaging protocols and train users in nuclear medicine and radiology. In this review we discuss three existing hybrid modalities with emphasis on their technical aspects and clinical applications in oncology. PMID:26320423

  1. Improved hybrid rocket fuel

    NASA Technical Reports Server (NTRS)

    Dean, David L.

    1995-01-01

    McDonnell Douglas Aerospace, as part of its Independent R&D, has initiated development of a clean burning, high performance hybrid fuel for consideration as an alternative to the solid rocket thrust augmentation currently utilized by American space launch systems including Atlas, Delta, Pegasus, Space Shuttle, and Titan. It could also be used in single stage to orbit or as the only propulsion system in a new launch vehicle. Compared to solid propellants based on aluminum and ammonium perchlorate, this fuel is more environmentally benign in that it totally eliminates hydrogen chloride and aluminum oxide by products, producing only water, hydrogen, nitrogen, carbon oxides, and trace amounts of nitrogen oxides. Compared to other hybrid fuel formulations under development, this fuel is cheaper, denser, and faster burning. The specific impulse of this fuel is comparable to other hybrid fuels and is between that of solids and liquids. The fuel also requires less oxygen than similar hybrid fuels to produce maximum specific impulse, thus reducing oxygen delivery system requirements.

  2. HYBRID RECEPTOR MODELS

    EPA Science Inventory

    A hybrid receptor model is a specified mathematical procedure which uses not only the ambient species concentration measurements that form the input data for a pure receptor model, but in addition source emission rates or atmospheric dispersion or transformation information chara...

  3. Hybridized polymer matrix composites

    NASA Technical Reports Server (NTRS)

    House, E. E.; Hoggatt, J. T.; Symonds, W. A.

    1980-01-01

    The extent to which graphite fibers are released from resin matrix composites that are exposed to fire and impact conditions was determined. Laboratory simulations of those conditions that could exist in the event of an aircraft crash and burn situation were evaluated. The effectiveness of various hybridizing concepts in preventing this release of graphite fibers were also evaluated. The baseline (i.e., unhybridized) laminates examined were prepared from commercially available graphite/epoxy, graphite/polyimide, and graphite/phenolic materials. Hybridizing concepts investigated included resin fillers, laminate coatings, resin blending, and mechanical interlocking of the graphite reinforcement. The baseline and hybridized laminates' mechanical properties, before and after isothermal and humidity aging, were also compared. It was found that a small amount of graphite fiber was released from the graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that several hybrid concepts eliminated this fiber release. Isothermal and humidity aging did not appear to alter the fiber release tendencies.

  4. Hybrid Anisotropic Micromesh

    NASA Astrophysics Data System (ADS)

    Gutzov, S.; Danchova, N.; Tsekov, R.; Barreno, I.; Ruiz del Portal, X.; Ulbikas, J.

    2015-10-01

    A new hybrid woven micromesh containing metal and polyester wires with a 2D porosity of about 30% has been created. The anisotropic microcomposite is developed as a new material with wide applications in thermal and electrical engineering. The mesh material is carefully characterized using electron microscopy, fluorescence microscopy, chemical analysis, thermal conductivity measurements and differential scanning calorimetry.

  5. Electric and hybrid vehicles

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Report characterizes state-of-the-art electric and hybrid (combined electric and heat engine) vehicles. Performance data for representative number of these vehicles were obtained from track and dynamometer tests. User experience information was obtained from fleet operators and individual owners of electric vehicles. Data on performance and physical characteristics of large number of vehicles were obtained from manufacturers and available literature.

  6. Hybridization of biomedical circuitry

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.

    1978-01-01

    The design and fabrication of low power hybrid circuits to perform vital signs monitoring are reported. The circuits consist of: (1) clock; (2) ECG amplifier and cardiotachometer signal conditioner; (3) impedance pneumobraph and respiration rate processor; (4) hear/breath rate processor; (5) temperature monitor; and (6) LCD display.

  7. Hybrid Solar GHP Simulator

    Energy Science and Technology Software Center (ESTSC)

    2012-12-11

    This project provides an easy-to-use, menu-driven, software tool for designing hybrid solar-geothermal heat pump systems (GHP) for both heating- and cooling-dominated buildings. No such design tool currently exists. In heating-dominated buildings, the design approach takes advantage of glazed solar collectors to effectively balance the annual thermal loads on the ground with renewable solar energy. In cooling-dominated climates, the design approach takes advantage of relatively low-cost, unglazed solar collectors as the heat rejecting component. The primarymore » benefit of hybrid GHPs is the reduced initial cost of the ground heat exchanger (GHX). Furthermore, solar thermal collectors can be used to balance the ground loads over the annual cycle, thus making the GHX fully sustainable; in heating-dominated buildings, the hybrid energy source (i.e., solar) is renewable, in contrast to a typical fossil fuel boiler or electric resistance as the hybrid component; in cooling-dominated buildings, use of unglazed solar collectors as a heat rejecter allows for passive heat rejection, in contrast to a cooling tower that consumes a significant amount of energy to operate, and hybrid GHPs can expand the market by allowing reduced GHX footprint in both heating- and cooling-dominated climates. The design tool allows for the straight-forward design of innovative GHP systems that currently pose a significant design challenge. The project lays the foundations for proper and reliable design of hybrid GHP systems, overcoming a series of difficult and cumbersome steps without the use of a system simulation approach, and without an automated optimization scheme. As new technologies and design concepts emerge, sophisticated design tools and methodologies must accompany them and be made usable for practitioners. Lack of reliable design tools results in reluctance of practitioners to implement more complex systems. A menu-driven software tool for the design of hybrid solar GHP systems

  8. Hybridization and introgression in two ecologically dissimilar Fundulus hybrid zones.

    PubMed

    Schaefer, Jacob; Duvernell, David; Campbell, Dave Cooper

    2016-05-01

    Hybridization and introgression appear more common in rapidly evolving groups, suggesting an important role in the evolutionary process. Detailed studies of how extrinsic or intrinsic forces regulate hybridization and introgression have the potential for broadening our understanding of mechanisms generating diversity. Species in the Fundulus notatus species complex have broad overlapping ranges and occur in replicated hybrid zones along predictable stream gradients. Typical hybrid zone structure has Fundulus olivaceus in headwaters, F. notatus downstream, and hybrid zones near confluences or abrupt shifts in habitat. Rarely, the typical upstream-downstream orientation is reversed raising questions as to how hybrid zones are formed and maintained. We used next-generation sequencing data to study hybridization and introgression in hybrid zones in neighboring drainages that differ in orientation (typical and reversed). We predicted extrinsic forces linked to stream gradients would result in noticeable differences between the two. Contrary to predictions, the data indicate the hybrid zones are remarkably similar. We used individual-based simulations to explore the potential role of intrinsic and extrinsic forces in generating and maintaining typical and reversed hybrid zones. Simulation results were consistent with reversed hybrid zones being formed from stochastic processes combined with strong intrinsic forces and weak extrinsic forces. PMID:27062071

  9. Hybrid Interventions in Limb Salvage

    PubMed Central

    Huynh, Tam T.T.; Bechara, Carlos F.

    2013-01-01

    Hybrid interventions have become an integral part of our strategy for limb salvage in patients with multilevel arterial occlusive disease. In this article, we describe the commonly used hybrid interventions and review their indications and outcomes. Iliac stenting and femoral endarterectomy are the two most frequently performed procedures in hybrid cases. Short- and long-term outcomes of hybrid interventions are at least comparable to conventional endovascular and surgical revascularization procedures. Hybrid revascularization offers the efficiency and convenience of a single-stage revascularization. PMID:23805341

  10. Backyard bolides: finding a buried impact crater.

    NASA Astrophysics Data System (ADS)

    Poag, C. W.

    1998-10-01

    The author reports the scientific activities that led to his discovery of a huge submerged impact crater in Chesapeake Bay, some 140 km east of Atlantic City, New Jersey. This crater, buried under 350 m of sediment is 80 km wide and almost 1 km deep. Microfossil evidence shows that the crater is approximately 35 million years old. The author futher identified 14 small secondary craters with diamters of 0.4 to 0.5 km diameter within 60 km of the primary crater. These were caused by the impact of huge blocks of material ejected by the primary impact event. In addition, the author identified an intermediate-size primary crater (19 km diameter) in Toms Canyon, some 300 km from the Chesapeake crater and, again from microfossil evidence, identical in age.

  11. The World Is Our Big Backyard!

    ERIC Educational Resources Information Center

    Wenze, Gloria T.; Fryer, Christine

    2010-01-01

    Sustainability is a contemporary term that calls attention to climate change and dwindling natural resources. Concerned about the urgency of sustainability and the long-range impact that non-sustainable efforts could have on the environment, and convinced that sustainable concepts could be taught to young children, the authors introduced an…

  12. Citizen Science in Your Own Backyard

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James; Guyton, John; Williams, Michael

    2012-01-01

    When does a scientific mentality begin, and why? Vertebrate paleontologist Edward Drinker Cope (1840-1897), known for Cope's Rule--that organisms of a species tend to get larger over time--recorded observations of "Ichthyosaurus," an extinct marine reptile, at the tender age of 6. He was obviously an inquisitive child. What about students of…

  13. Renewable Energy - Growing Opportunities in our Backyard

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Economic growth requires energy. Historically the United States has met this demand for energy by utilizing nonrenewable fossil fuels. Economic and environmental concerns at local, regional, and international levels are shifting attention to cleaner alternatives which are sustainable and renewable...

  14. Achieving Self-Reliance: Backyard Energy Lessons.

    ERIC Educational Resources Information Center

    Cook, Stephen

    Appropriate technology (the process most appropriate for local cultural, economic, and social conditions) is geared toward projects which: are small in scale, decentralized, and energy efficient; use local materials, labor, and ingenuity; are not capital-intensive; and maximize the use of renewable energy resources. Descriptions of such projects…

  15. Bug City: House and Backyard Insects [Videotape].

    ERIC Educational Resources Information Center

    1998

    "Bug City" is a video series created to help children learn about insects and other small critters. All aspects of bug life are touched upon including body structure, food, habitat, life cycle, mating habits, camouflage, mutualism (symbiosis), adaptations, social behavior, and more. Each program features dramatic microscopic photography, fun…

  16. Rethinking resources and hybridity

    NASA Astrophysics Data System (ADS)

    Gonsalves, Allison J.; Seiler, Gale; Salter, Dana E.

    2011-06-01

    This review explores Alfred Schademan's "What does playing cards have to do with science? A resource-rich view of African American young men" by examining how he uses two key concepts—hybridity and resources—to propose an approach to science education that counters enduring deficit notions associated with this population. Our response to Schademan's work expands upon his definition of hybridity and its purpose in the science classroom and highlights the tensions inherent in the appropriation of student resources in classroom spaces. This conversation points also to the need for research analyses and pedagogical approaches that simultaneously valorize student resources, allow student opportunities to learn the dominant codes, and provide teacher and student opportunities to transform them. Carol Lee's notion of "cultural modeling" is discussed as a possible framing device to facilitate this kind of research.

  17. Pulsed hybrid field emitter

    DOEpatents

    Sampayan, Stephen E.

    1998-01-01

    A hybrid emitter exploits the electric field created by a rapidly depoled ferroelectric material. Combining the emission properties of a planar thin film diamond emitter with a ferroelectric alleviates the present technological problems associated with both types of emitters and provides a robust, extremely long life, high current density cathode of the type required by emerging microwave power generation, accelerator technology and display applications. This new hybrid emitter is easy to fabricate and not susceptible to the same failures which plague microstructure field emitter technology. Local electrode geometries and electric field are determined independently from those for optimum transport and brightness preservation. Due to the large amount of surface charge created on the ferroelectric, the emitted electrons have significant energy, thus eliminating the requirement for specialized phosphors in emissive flat-panel displays.

  18. Pulsed hybrid field emitter

    DOEpatents

    Sampayan, S.E.

    1998-03-03

    A hybrid emitter exploits the electric field created by a rapidly depoled ferroelectric material. Combining the emission properties of a planar thin film diamond emitter with a ferroelectric alleviates the present technological problems associated with both types of emitters and provides a robust, extremely long life, high current density cathode of the type required by emerging microwave power generation, accelerator technology and display applications. This new hybrid emitter is easy to fabricate and not susceptible to the same failures which plague microstructure field emitter technology. Local electrode geometries and electric field are determined independently from those for optimum transport and brightness preservation. Due to the large amount of surface charge created on the ferroelectric, the emitted electrons have significant energy, thus eliminating the requirement for specialized phosphors in emissive flat-panel displays. 11 figs.

  19. Hybridized polymer matrix composites

    NASA Technical Reports Server (NTRS)

    London, A.

    1981-01-01

    Design approaches and materials are described from which are fabricated pyrostatic graphite/epoxy (Gr/Ep) laminates that show improved retention of graphite particulates when subjected to burning. Sixteen hybridized plus two standard Gr/Ep laminates were designed, fabricated, and tested in an effort to eliminate the release of carbon (graphite) fiber particles from burned/burning, mechanically disturbed samples. The term pyrostatic is defined as meaning mechanically intact in the presence of fire. Graphite particulate retentive laminates were constructed whose constituent materials, cost of fabrication, and physical and mechanical properties were not significantly different from existing Gr/Ep composites. All but one laminate (a Celion graphite/bis-maleimide polyimide) were based on an off-the-shelf Gr/Ep, the AS-1/3501-5A system. Of the 16 candidates studied, four thin (10-ply) and four thick (50-ply) hybridized composites are recommended.

  20. Hybrid plasma modeling.

    SciTech Connect

    Hopkins, Matthew Morgan; DeChant, Lawrence Justin.; Piekos, Edward Stanley; Pointon, Timothy David

    2009-02-01

    This report summarizes the work completed during FY2007 and FY2008 for the LDRD project ''Hybrid Plasma Modeling''. The goal of this project was to develop hybrid methods to model plasmas across the non-continuum-to-continuum collisionality spectrum. The primary methodology to span these regimes was to couple a kinetic method (e.g., Particle-In-Cell) in the non-continuum regions to a continuum PDE-based method (e.g., finite differences) in continuum regions. The interface between the two would be adjusted dynamically ased on statistical sampling of the kinetic results. Although originally a three-year project, it became clear during the second year (FY2008) that there were not sufficient resources to complete the project and it was terminated mid-year.

  1. Hybrid superconducting magnetic suspensions

    SciTech Connect

    Tixador, P.; Hiebel, P.; Brunet, Y.

    1996-07-01

    Superconductors, especially high T{sub c} ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms of forces and stiffnesses. The design of the magnet bearing plays an important part. The superconducting magnetic bearing participates less in levitation but must provide a high stabilizing stiffness. This is achieved by the magnet configuration, a good material in term of critical current density and field cooling. A hybrid superconducting suspension for a flywheel is presented. This system consists of a magnet thrust bearing stabilized by superconductors interacting with an alternating polarity magnet structure. First tests and results are reported. Superconducting materials are magnetically melt-textured YBaCuO.

  2. Sneutrino Hybrid Inflation

    SciTech Connect

    Antusch, Stefan

    2006-11-28

    We review the scenario of sneutrino hybrid inflation, where one of the singlet sneutrinos, the superpartners of the right-handed neutrinos, plays the role of the inflaton. In a minimal model of sneutrino hybrid inflation, the spectral index is given by ns {approx_equal} 1 + 2{gamma}. With {gamma} = 0.025 {+-} 0.01 constrained by WMAP, a running spectral index vertical bar dns/dlnk vertical bar << vertical bar{gamma}vertical bnd a tensor-to-scalar ratio r << {gamma}2 are predicted. Small neutrino masses arise from the seesaw mechanism, with heavy masses for the singlet (s)neutrinos generated by the vacuum expectation value of the waterfall field after inflation. The baryon asymmetry of the universe can be explained by non-thermal leptogenesis via sneutrino inflaton decay, with low reheat temperature TRH {approx_equal} 106 GeV.

  3. Hybrid Neurofibroma-Schwannoma.

    PubMed

    Hussain, Namath S; Specht, Charles S; Frauenhoffer, Elizabeth; Glantz, Michael; Harbaugh, Kimberly

    2016-01-01

    Neurofibromas and schwannomas are common lesions that may be idiopathic or may occur in association with neural crest genetic syndromes such as neurofibromatosis type 1, neurofibromatosis type 2, and schwannomatosis. A hybrid tumor that contains pathological characteristics of both neurofibroma and schwannoma has been described as a rare entity. We present the clinical, radiographic, and pathological findings of such a case. PMID:27158577

  4. Hybrid undulator numerical optimization

    SciTech Connect

    Hairetdinov, A.H.; Zukov, A.A.

    1995-12-31

    3D properties of the hybrid undulator scheme arc studied numerically using PANDIRA code. It is shown that there exist two well defined sets of undulator parameters which provide either maximum on-axis field amplitude or minimal higher harmonics amplitude of the basic undulator field. Thus the alternative between higher field amplitude or pure sinusoidal field exists. The behavior of the undulator field amplitude and harmonics structure for a large set of (undulator gap)/(undulator wavelength) values is demonstrated.

  5. Fibonacci-Pell Hybridities

    ERIC Educational Resources Information Center

    Koshy, Thomas; Gao, Zhenguang

    2012-01-01

    We develop a recurrence satisfied by the Fibonacci and Pell families. We then use it to find explicit formulae and generating functions for the hybrids "F[subscript n]P[subscript n]", "L[subscript n]P[subscript n]", "F[subscript n]Q[subscript n]" and "L[subscript n]Q[subscript n]", where "F[subscript n]", "L[subscript n]", "P[subscript n]" and…

  6. Hybrid electroluminescent devices

    DOEpatents

    Shiang, Joseph John; Duggal, Anil Raj; Michael, Joseph Darryl

    2010-08-03

    A hybrid electroluminescent (EL) device comprises at least one inorganic diode element and at least one organic EL element that are electrically connected in series. The absolute value of the breakdown voltage of the inorganic diode element is greater than the absolute value of the maximum reverse bias voltage across the series. The inorganic diode element can be a power diode, a Schottky barrier diode, or a light-emitting diode.

  7. Cold Hybrid Star Properties

    SciTech Connect

    Moshfegh, H. R.; Darehmoradi, M.; Mojarrad, M. Ghazanfari

    2011-10-28

    Properties of neutron stars with quark core are investigated. The equation of state of hadronic matter is calculated using Myers and Swiatecki two nucleon interaction within Thomas-Fermi semiclassical approximation (TF). For quark matter we employ The MIT bag model with constant and density dependent bag parameter. With use of the obtained equation of states we have calculated mass-radius relation of such hybrid stars.

  8. Hybrid knowledge systems

    NASA Technical Reports Server (NTRS)

    Subrahmanian, V. S.

    1994-01-01

    An architecture called hybrid knowledge system (HKS) is described that can be used to interoperate between a specification of the control laws describing a physical system, a collection of databases, knowledge bases and/or other data structures reflecting information about the world in which the physical system controlled resides, observations (e.g. sensor information) from the external world, and actions that must be taken in response to external observations.

  9. Hybrid Neurofibroma-Schwannoma

    PubMed Central

    Specht, Charles S; Frauenhoffer, Elizabeth; Glantz, Michael; Harbaugh, Kimberly

    2016-01-01

    Neurofibromas and schwannomas are common lesions that may be idiopathic or may occur in association with neural crest genetic syndromes such as neurofibromatosis type 1, neurofibromatosis type 2, and schwannomatosis. A hybrid tumor that contains pathological characteristics of both neurofibroma and schwannoma has been described as a rare entity. We present the clinical, radiographic, and pathological findings of such a case. PMID:27158577

  10. Printed hybrid systems

    NASA Astrophysics Data System (ADS)

    Karioja, Pentti; Mäkinen, Jukka-Tapani; Keränen, Kimmo; Aikio, Janne; Alajoki, Teemu; Jaakola, Tuomo; Koponen, Matti; Keränen, Antti; Heikkinen, Mikko; Tuomikoski, Markus; Suhonen, Riikka; Hakalahti, Leena; Kopola, Pälvi; Hast, Jukka; Liedert, Ralf; Hiltunen, Jussi; Masuda, Noriyuki; Kemppainen, Antti; Rönkä, Kari; Korhonen, Raimo

    2012-04-01

    This paper presents research activities carried out at VTT Technical Research Centre of Finland in the field of hybrid integration of optics, electronics and mechanics. Main focus area in our research is the manufacturing of electronic modules and product structures with printed electronics, film-over-molding and polymer sheet lamination technologies and the goal is in the next generation of smart systems utilizing monolithic polymer packages. The combination of manufacturing technologies such as roll-to-roll -printing, injection molding and traditional component assembly is called Printed Hybrid Systems (PHS). Several demonstrator structures have been made, which show the potential of polymer packaging technology. One demonstrator example is a laminated structure with embedded LED chips. Element thickness is only 0.3mm and the flexible stack of foils can be bent in two directions after assembly process and was shaped curved using heat and pressure. The combination of printed flexible circuit boards and injection molding has also been demonstrated with several functional modules. The demonstrators illustrate the potential of origami electronics, which can be cut and folded to 3D shapes. It shows that several manufacturing process steps can be eliminated by Printed Hybrid Systems technology. The main benefits of this combination are small size, ruggedness and conformality. The devices are ideally suited for medical applications as the sensitive electronic components are well protected inside the plastic and the structures can be cleaned easily due to the fact that they have no joints or seams that can accumulate dirt or bacteria.

  11. Asymmetric Hybrid Nanoparticles

    SciTech Connect

    Chumanov, George

    2015-11-05

    Hybrid Nanoparticles (AHNs) are rationally-designed multifunctional nanostructures and novel building blocks for the next generation of advanced materials and devices. Nanoscale materials attract considerable interest because of their unusual properties and potential for practical applications. Most of the activity in this field is focused on the synthesis of homogeneous nanoparticles from metals, metal oxides, semiconductors, and polymers. It is well recognized that properties of nanoparticles can be further enhanced if they are made as hybrid structures. This program is concerned with the synthesis, characterization, and application of such hybrid structures termed AHNs. AHNs are composed of a homogeneous core and several caps of different materials deposited on its surface (Fig. 1). Combined properties of the core and the caps as well as new properties that arise from core-cap and cap-cap interactions render AHNs multifunctional. In addition, specific chemical reactivity of the caps enables directional self-assembly of AHNs into complex architectures that are not possible with only spherical nanoparticles.

  12. Hybrid Propulsion Technology Program

    NASA Technical Reports Server (NTRS)

    Jensen, G. E.; Holzman, A. L.

    1990-01-01

    Future launch systems of the United States will require improvements in booster safety, reliability, and cost. In order to increase payload capabilities, performance improvements are also desirable. The hybrid rocket motor (HRM) offers the potential for improvements in all of these areas. The designs are presented for two sizes of hybrid boosters, a large 4.57 m (180 in.) diameter booster duplicating the Advanced Solid Rocket Motor (ASRM) vacuum thrust-time profile and smaller 2.44 m (96 in.), one-quater thrust level booster. The large booster would be used in tandem, while eight small boosters would be used to achieve the same total thrust. These preliminary designs were generated as part of the NASA Hybrid Propulsion Technology Program. This program is the first phase of an eventual three-phaes program culminating in the demonstration of a large subscale engine. The initial trade and sizing studies resulted in preferred motor diameters, operating pressures, nozzle geometry, and fuel grain systems for both the large and small boosters. The data were then used for specific performance predictions in terms of payload and the definition and selection of the requirements for the major components: the oxidizer feed system, nozzle, and thrust vector system. All of the parametric studies were performed using realistic fuel regression models based upon specific experimental data.

  13. Hybrid X-pinches

    SciTech Connect

    Shelkovenko, T. A.; Pikuz, S. A.; Mishin, S. A.; Mingaleev, A. R.; Tilikin, I. N.; Knapp, P. F.; Cahill, A. D.; Hoyt, C. L.; Hammer, D. A.

    2012-05-15

    Results from experimental studies of a hybrid X-pinch with an initial configuration in the form of a high-current diode with conical tungsten electrodes spaced by 1-2 mm and connected to one another with 20- to 100-{mu}m-diameter wires are presented. The experiments were carried out at four facilities with a current amplitude from 200 to 1000 kA and front duration from 45 to 200 ns. It is shown that, in spite of their simpler configuration, hybrid X-pinches with a short rise time of the current pulse (50-100 ns) are highly competitive with standard X-pinches in the generated soft X-ray power and the formation of a single hot spot in them is much more stable, while hard X-ray emission is almost absent. The possibility of using hybrid X-pinches as soft X-ray sources for point projection X-ray imaging of plasma objects is considered.

  14. Hybrid2 - The hybrid power system simulation model

    SciTech Connect

    Baring-Gould, E.I.; Green, H.J.; Dijk, V.A.P. van; Manwell, J.F.

    1996-12-31

    There is a large-scale need and desire for energy in remote communities, especially in the developing world; however the lack of a user friendly, flexible performance prediction model for hybrid power systems incorporating renewables hindered the analysis of hybrids as options to conventional solutions. A user friendly model was needed with the versatility to simulate the many system locations, widely varying hardware configurations, and differing control options for potential hybrid power systems. To meet these ends, researchers from the National Renewable Energy Laboratory (NREL) and the University of Massachusetts (UMass) developed the Hybrid2 software. This paper provides an overview of the capabilities, features, and functionality of the Hybrid2 code, discusses its validation and future plans. Model availability and technical support provided to Hybrid2 users are also discussed. 12 refs., 3 figs., 4 tabs.

  15. KIC 9533489: a genuine γ Doradus - δ Scuti Kepler hybrid pulsator with transit events

    NASA Astrophysics Data System (ADS)

    Bognár, Zs.; Lampens, P.; Frémat, Y.; Southworth, J.; Sódor, Á.; De Cat, P.; Isaacson, H. T.; Marcy, G. W.; Ciardi, D. R.; Gilliland, R. L.; Martín-Fernández, P.

    2015-09-01

    Context. Several hundred candidate hybrid pulsators of type A-F have been identified from space-based observations. Their large number allows both statistical analyses and detailed investigations of individual stars. This offers the opportunity to study the full interior of the genuine hybrids, in which both low radial order p- and high-order g-modes are self-excited at the same time. However, a few other physical processes can also be responsible for the observed hybrid nature, related to binarity or to surface inhomogeneities. The finding that most δ Scuti stars also show long-period light variations represents a real challenge for theory. Aims: We aim at determining the pulsation frequencies of KIC 9533489, to search for regular patterns and spacings among them, and to investigate the stability of the frequencies and the amplitudes. An additional goal is to study the serendipitously detected transit events: is KIC 9533489 the host star? What are the limitations on the physical parameters of the involved bodies? Methods: We performed a Fourier analysis of all the available Kepler light curves. We investigated the frequency and period spacings and determined the stellar physical parameters from spectroscopic observations. We also modelled the transit events. Results: The Fourier analysis of the Kepler light curves revealed 55 significant frequencies clustered into two groups, which are separated by a gap between 15 and 27 d-1. The light variations are dominated by the beating of two dominant frequencies located at around 4 d-1. The amplitudes of these two frequencies show a monotonic long-term trend. The frequency spacing analysis revealed two possibilities: the pulsator is either a highly inclined moderate rotator (v ≈ 70 km s-1, i> 70°) or a fast rotator (v ≈ 200 km s-1) with i ≈ 20°. The transit analysis disclosed that the transit events that occur with a ≈197 d period may be caused by a 1.6 RJup body orbiting a fainter star, which would be spatially

  16. Solar thermal electric hybridization issues

    SciTech Connect

    Williams, T A; Bohn, M S; Price, H W

    1994-10-01

    Solar thermal electric systems have an advantage over many other renewable energy technologies because the former use heat as an intermediate energy carrier. This is an advantage as it allows for a relatively simple method of hybridization by using heat from fossil-fuel. Hybridization of solar thermal electric systems is a topic that has recently generated significant interest and controversy and has led to many diverse opinions. This paper discusses many of the issues associated with hybridization of solar thermal electric systems such as what role hybridization should play; how it should be implemented; what are the efficiency, environmental, and cost implications; what solar fraction is appropriate; how hybrid systems compete with solar-only systems; and how hybridization can impact commercialization efforts for solar thermal electric systems.

  17. The XMM-Newton serendipitous survey. VII. The third XMM-Newton serendipitous source catalogue

    NASA Astrophysics Data System (ADS)

    Rosen, S. R.; Webb, N. A.; Watson, M. G.; Ballet, J.; Barret, D.; Braito, V.; Carrera, F. J.; Ceballos, M. T.; Coriat, M.; Della Ceca, R.; Denkinson, G.; Esquej, P.; Farrell, S. A.; Freyberg, M.; Grisé, F.; Guillout, P.; Heil, L.; Koliopanos, F.; Law-Green, D.; Lamer, G.; Lin, D.; Martino, R.; Michel, L.; Motch, C.; Nebot Gomez-Moran, A.; Page, C. G.; Page, K.; Page, M.; Pakull, M. W.; Pye, J.; Read, A.; Rodriguez, P.; Sakano, M.; Saxton, R.; Schwope, A.; Scott, A. E.; Sturm, R.; Traulsen, I.; Yershov, V.; Zolotukhin, I.

    2016-05-01

    Context. Thanks to the large collecting area (3 ×~1500 cm2 at 1.5 keV) and wide field of view (30' across in full field mode) of the X-ray cameras on board the European Space Agency X-ray observatory XMM-Newton, each individual pointing can result in the detection of up to several hundred X-ray sources, most of which are newly discovered objects. Since XMM-Newton has now been in orbit for more than 15 yr, hundreds of thousands of sources have been detected. Aims: Recently, many improvements in the XMM-Newton data reduction algorithms have been made. These include enhanced source characterisation and reduced spurious source detections, refined astrometric precision of sources, greater net sensitivity for source detection, and the extraction of spectra and time series for fainter sources, both with better signal-to-noise. Thanks to these enhancements, the quality of the catalogue products has been much improved over earlier catalogues. Furthermore, almost 50% more observations are in the public domain compared to 2XMMi-DR3, allowing the XMM-Newton Survey Science Centre to produce a much larger and better quality X-ray source catalogue. Methods: The XMM-Newton Survey Science Centre has developed a pipeline to reduce the XMM-Newton data automatically. Using the latest version of this pipeline, along with better calibration, a new version of the catalogue has been produced, using XMM-Newton X-ray observations made public on or before 2013 December 31. Manual screening of all of the X-ray detections ensures the highest data quality. This catalogue is known as 3XMM. Results: In the latest release of the 3XMM catalogue, 3XMM-DR5, there are 565 962 X-ray detections comprising 396 910 unique X-ray sources. Spectra and lightcurves are provided for the 133 000 brightest sources. For all detections, the positions on the sky, a measure of the quality of the detection, and an evaluation of the X-ray variability is provided, along with the fluxes and count rates in 7 X-ray energy bands, the total 0.2-12 keV band counts, and four hardness ratios. With the aim of identifying the detections, a cross correlation with 228 catalogues of sources detected in all wavebands is also provided for each X-ray detection. Conclusions: 3XMM-DR5 is the largest X-ray source catalogue ever produced. Thanks to the large array of data products associated with each detection and each source, it is an excellent resource for finding new and extreme objects. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.The catalogue is available at http://cdsarc.u-strasbg.fr/viz-bin/VizieR?-meta.foot&-source=IX/46

  18. Hybrid solar lighting systems and components

    DOEpatents

    Muhs, Jeffrey D.; Earl, Dennis D.; Beshears, David L.; Maxey, Lonnie C.; Jordan, John K.; Lind, Randall F.

    2007-06-12

    A hybrid solar lighting system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates each component.

  19. Hybrid solar lighting distribution systems and components

    DOEpatents

    Muhs, Jeffrey D.; Earl, Dennis D.; Beshears, David L.; Maxey, Lonnie C.; Jordan, John K.; Lind, Randall F.

    2011-07-05

    A hybrid solar lighting distribution system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates all components.

  20. Global trends in hybrid imaging.

    PubMed

    Hricak, Hedvig; Choi, Byung Ihn; Scott, Andrew M; Sugimura, Kazuro; Muellner, Ada; von Schulthess, Gustav K; Reiser, Maximilian F; Graham, Michael M; Dunnick, N Reed; Larson, Steven M

    2010-11-01

    At the 2009 Scientific Assembly and Annual Meeting of the Radiological Society of North America, a special session was devoted to global trends in hybrid imaging. This article expands on the key points of the session, focusing primarily on positron emission tomography/computed tomography. Global trends in hybrid imaging equipment acquisition, usage, and image interpretation practices are reviewed, and emerging requirements for training and clinical privileging are discussed. Also considered are the current benefits of hybrid imaging for patient care and workflow and the potential of hybrid imaging for advancing drug development and personalized medicine. PMID:20829539

  1. Colloidal thermoresponsive gel forming hybrids.

    PubMed

    Liu, Ruixue; Tirelli, Nicola; Cellesi, Francesco; Saunders, Brian R

    2010-09-15

    Colloidal hybrids comprise organic and inorganic components and are attracting considerable attention in the literature. Recently, we reported hybrid anisotropic microsheets that formed thermoresponsive gels in polymer solutions [Liu et al., Langmuir, 25, 490, 2009]. Here, we investigate the composition and properties of these hybrid colloids themselves in detail for the first time. Three different cationic PNIPAm (N-isopropylacrylamide) graft copolymers and two inorganic nanoparticle types (laponite and Ludox silica) were used to prepare a range of hybrids. Anisotropic microsheets only formed when laponite particles were added to the copolymer implying directed self-assembly. Aqueous dispersions of the microsheets spontaneously formed gels at room temperature and these gels were thermoresponsive. They represent a new class of gel forming colloid and are termed thermoresponsive gel forming hybrids. The compositions of the hybrids were determined from thermogravimetric analysis and those that gave gel forming behaviour identified. Variable-temperature rheology experiments showed that the elasticity of the gels increased linearly with temperature. The reversibility of the thermally-triggered changes in gel elasticity was investigated. The concentration dependence of the rheology data was well described by elastic percolation scaling theory and the data could be collapsed onto a master curve. The concentration exponent for the elastic modulus was 2.5. The strong attractive interactions that exist between the dispersed gel forming hybrids was demonstrated by the formation of stable thermoresponsive hybrid hydrogels through casting of hybrid dispersions. PMID:20561633

  2. Hybridized Graphene Materials

    NASA Astrophysics Data System (ADS)

    Robinson, Jeremy

    2015-03-01

    Graphene's high-quality structure and properties continue to motivate intensive research to mold it into the electronic material of the future. Analogous to other electronic materials, however, defects are a tool to engineer graphene's properties and tune its response to various stimuli. In this talk I discuss our efforts to engineer and manipulate defects in hybrid graphene materials for applications ranging from sensing to nanomechanical structures. First, I will present our results using chemically modified graphene to not only improve chemical sensing, but also achieve new functionality for electronic systems. In particular, we hybridize graphene via the addition of fluorine atoms and show the subsequent formation of nanoribbons and tunnel barriers exploiting property changes from the fluorine adsorbates. Second, I will present results on the electronic hybridization of stacked graphene layers, where the moiré pattern formed by the relative twist between layers is responsible for new properties of the bilayer system. Defects specific to this system include rotational disorder, strain, and chemical doping. These defects modify, but do not destroy the strong interlayer coupling. Finally, I will present results on the influence of chemistry and defects on the properties of graphene nanomechanical systems. By measuring the response of high-quality nanomehcanical resonators, we can extract relevant mechanical properties including tension, yield strength, resilience, and modulus as a function of defect introduction. This work is carried out in collaboration with M. Zalalutdinov, P.E. Sheehan, W.-K. Lee, T. Reinecke, S.W. Schmucker, J.C. Culbertson, and A.L. Friedman at Naval Research Laboratory, and T. Ohta, T.E. Beechem and B. Diaconescu at Sandia National Laboratories.

  3. Hybrid receiver study

    NASA Technical Reports Server (NTRS)

    Stone, M. S.; Mcadam, P. L.; Saunders, O. W.

    1977-01-01

    The results are presented of a 4 month study to design a hybrid analog/digital receiver for outer planet mission probe communication links. The scope of this study includes functional design of the receiver; comparisons between analog and digital processing; hardware tradeoffs for key components including frequency generators, A/D converters, and digital processors; development and simulation of the processing algorithms for acquisition, tracking, and demodulation; and detailed design of the receiver in order to determine its size, weight, power, reliability, and radiation hardness. In addition, an evaluation was made of the receiver's capabilities to perform accurate measurement of signal strength and frequency for radio science missions.

  4. Hybrid power semiconductor

    NASA Technical Reports Server (NTRS)

    Chen, D. Y.

    1985-01-01

    The voltage rating of a bipolar transistor may be greatly extended while at the same time reducing its switching time by operating it in conjunction with FETs in a hybrid circuit. One FET is used to drive the bipolar transistor while the other FET is connected in series with the transistor and an inductive load. Both FETs are turned on or off by a single drive signal of load power, the second FET upon ceasing conductions, rendering one power electrode of the bipolar transistor open. Means are provided to dissipate currents which flow after the bipolar transistor is rendered nonconducting.

  5. Hybrid Terrain Database

    NASA Technical Reports Server (NTRS)

    Arthur, Trey

    2006-01-01

    A prototype hybrid terrain database is being developed in conjunction with other databases and with hardware and software that constitute subsystems of aerospace cockpit display systems (known in the art as synthetic vision systems) that generate images to increase pilots' situation awareness and eliminate poor visibility as a cause of aviation accidents. The basic idea is to provide a clear view of the world around an aircraft by displaying computer-generated imagery derived from an onboard database of terrain, obstacle, and airport information.

  6. Robust hybrid mass damper

    NASA Astrophysics Data System (ADS)

    Collette, C.; Chesné, S.

    2016-08-01

    In this paper, the design of a hybrid mass damper (HMD) is proposed for the reduction of the resonant vibration amplitude of a multiple degree-of-freedom structure. HMD includes both passive and active elements. Combining these elements the system is fail-safe and its performances are comparable to usual purely active systems. The control law is a revisited direct velocity feedback. Two zeros are added to the controller to interact with the poles of the plant. The developed control law presents the particularity to be simple and hyperstable. The proposed HMD is compared to other classical control approaches for similar purpose in term of vibration attenuation, power consumption and stroke.

  7. Cryogenic Hybrid Magnetic Bearing

    NASA Technical Reports Server (NTRS)

    Meeks, Crawford R.; Dirusso, Eliseo; Brown, Gerald V.

    1994-01-01

    Cryogenic hybrid magnetic bearing is example of class of magnetic bearings in which permanent magnets and electromagnets used to suspend shafts. Electromagnets provide active control of position of shaft. Bearing operates at temperatures from -320 degrees F (-196 degrees C) to 650 degrees F (343 degrees C); designed for possible use in rocket-engine turbopumps, where effects of cryogenic environment and fluid severely limit lubrication of conventional ball bearings. This and similar bearings also suitable for terrestrial rotating machinery; for example, gas-turbine engines, high-vacuum pumps, canned pumps, precise gimbals that suspend sensors, and pumps that handle corrosive or gritty fluids.

  8. Competitive hybridization models

    NASA Astrophysics Data System (ADS)

    Cherepinsky, Vera; Hashmi, Ghazala; Mishra, Bud

    2010-11-01

    Microarray technology, in its simplest form, allows one to gather abundance data for target DNA molecules, associated with genomes or gene-expressions, and relies on hybridizing the target to many short probe oligonucleotides arrayed on a surface. While for such multiplexed reactions conditions are optimized to make the most of each individual probe-target interaction, subsequent analysis of these experiments is based on the implicit assumption that a given experiment yields the same result regardless of whether it was conducted in isolation or in parallel with many others. It has been discussed in the literature that this assumption is frequently false, and its validity depends on the types of probes and their interactions with each other. We present a detailed physical model of hybridization as a means of understanding probe interactions in a multiplexed reaction. Ultimately, the model can be derived from a system of ordinary differential equations (ODE’s) describing kinetic mass action with conservation-of-mass equations completing the system. We examine pairwise probe interactions in detail and present a model of “competition” between the probes for the target—especially, when the target is effectively in short supply. These effects are shown to be predictable from the affinity constants for each of the four probe sequences involved, namely, the match and mismatch sequences for both probes. These affinity constants are calculated from the thermodynamic parameters such as the free energy of hybridization, which are in turn computed according to the nearest neighbor (NN) model for each probe and target sequence. Simulations based on the competitive hybridization model explain the observed variability in the signal of a given probe when measured in parallel with different groupings of other probes or individually. The results of the simulations can be used for experiment design and pooling strategies, based on which probes have been shown to have a strong

  9. The Hybrid Advantage: Graduate Student Perspectives of Hybrid Education Courses

    ERIC Educational Resources Information Center

    Hall, Sarah; Villareal, Donna

    2015-01-01

    Hybrid courses combine online and face-to-face learning environments. To organize and teach hybrid courses, instructors must understand the uses of multiple online learning tools and face-toface classroom activities to promote and monitor the progress of students. The purpose of this phenomenological study was to explore the perspectives of…

  10. Hybrid vehicle potential assessment. Volume 7: Hybrid vehicle review

    NASA Technical Reports Server (NTRS)

    Leschly, K. O.

    1979-01-01

    Review of hybrid vehicles built during the past ten years or planned to be built in the near future is presented. An attempt is made to classify and analyze these vehicles to get an overall picture of their key characteristics. The review includes onroad hybrid passenger cars, trucks, vans, and buses.

  11. Phoxonic Hybrid Superlattice.

    PubMed

    Alonso-Redondo, Elena; Huesmann, Hannah; El Boudouti, El-Houssaine; Tremel, Wolfgang; Djafari-Rouhani, Bahram; Butt, Hans-Juergen; Fytas, George

    2015-06-17

    We studied experimentally and theoretically the direction-dependent elastic and electromagnetic wave propagation in a supported film of hybrid PMMA (poly[methyl-methacrylate])-TiO2 superlattice (SL). In the direction normal to the layers, this one-dimensional periodic structure opens propagation band gaps for both hypersonic (GHz) phonons and near-UV photons. The high mismatch of elastic and optical impedance results in a large dual phoxonic band gap. The presence of defects inherent to the spin-coating fabrication technique is sensitively manifested in the band gap region. Utilizing Brillouin light scattering, phonon propagation along the layers was observed to be distinctly different from propagation normal to them and can, under certain conditions (SL thickness and substrate elasticity), reveal the nanomechanical properties of the constituent layers. Besides the first realization of unidirectional phoxonic behavior, hybrid (soft-hard) periodic materials are a promising simple platform for opto-acoustic interactions and applications such as filters and Bragg mirrors. PMID:25855860

  12. New smooth hybrid inflation

    SciTech Connect

    Lazarides, George; Vamvasakis, Achilleas

    2007-10-15

    We consider the extension of the supersymmetric Pati-Salam model which solves the b-quark mass problem of supersymmetric grand unified models with exact Yukawa unification and universal boundary conditions and leads to the so-called new shifted hybrid inflationary scenario. We show that this model can also lead to a new version of smooth hybrid inflation based only on renormalizable interactions provided that a particular parameter of its superpotential is somewhat small. The potential possesses valleys of minima with classical inclination, which can be used as inflationary paths. The model is consistent with the fitting of the three-year Wilkinson microwave anisotropy probe data by the standard power-law cosmological model with cold dark matter and a cosmological constant. In particular, the spectral index turns out to be adequately small so that it is compatible with the data. Moreover, the Pati-Salam gauge group is broken to the standard model gauge group during inflation and, thus, no monopoles are formed at the end of inflation. Supergravity corrections based on a nonminimal Kaehler potential with a convenient choice of a sign keep the spectral index comfortably within the allowed range without generating maxima and minima of the potential on the inflationary path. So, unnatural restrictions on the initial conditions for inflation can be avoided.

  13. Hybrid Turbine Electric Vehicle

    NASA Technical Reports Server (NTRS)

    Viterna, Larry A.

    1997-01-01

    Hybrid electric power trains may revolutionize today's ground passenger vehicles by significantly improving fuel economy and decreasing emissions. The NASA Lewis Research Center is working with industry, universities, and Government to develop and demonstrate a hybrid electric vehicle. Our partners include Bowling Green State University, the Cleveland Regional Transit Authority, Lincoln Electric Motor Division, the State of Ohio's Department of Development, and Teledyne Ryan Aeronautical. The vehicle will be a heavy class urban transit bus offering double the fuel economy of today's buses and emissions that are reduced to 1/10th of the Environmental Protection Agency's standards. At the heart of the vehicle's drive train is a natural-gas-fueled engine. Initially, a small automotive engine will be tested as a baseline. This will be followed by the introduction of an advanced gas turbine developed from an aircraft jet engine. The engine turns a high-speed generator, producing electricity. Power from both the generator and an onboard energy storage system is then provided to a variable-speed electric motor attached to the rear drive axle. An intelligent power-control system determines the most efficient operation of the engine and energy storage system.

  14. Arabidopsis hybrid speciation processes

    PubMed Central

    Schmickl, Roswitha; Koch, Marcus A.

    2011-01-01

    The genus Arabidopsis provides a unique opportunity to study fundamental biological questions in plant sciences using the diploid model species Arabidopsis thaliana and Arabidopsis lyrata. However, only a few studies have focused on introgression and hybrid speciation in Arabidopsis, although polyploidy is a common phenomenon within this genus. More recently, there is growing evidence of significant gene flow between the various Arabidopsis species. So far, we know Arabidopsis suecica and Arabidopsis kamchatica as fully stabilized allopolyploid species. Both species evolved during Pleistocene glaciation and deglaciation cycles in Fennoscandinavia and the amphi-Beringian region, respectively. These hybrid studies were conducted either on a phylogeographic scale or reconstructed experimentally in the laboratory. In our study we focus at a regional and population level. Our research area is located in the foothills of the eastern Austrian Alps, where two Arabidopsis species, Arabidopsis arenosa and A. lyrata ssp. petraea, are sympatrically distributed. Our hypothesis of genetic introgression, migration, and adaptation to the changing environment during the Pleistocene has been confirmed: We observed significant, mainly unidirectional gene flow between the two species, which has given rise to the tetraploid A. lyrata. This cytotype was able to escape from the narrow ecological niche occupied by diploid A. lyrata ssp. petraea on limestone outcrops by migrating northward into siliceous areas, leaving behind a trail of genetic differentiation. PMID:21825128

  15. Electric/Hybrid Vehicle Simulation

    NASA Technical Reports Server (NTRS)

    Slusser, R. A.; Chapman, C. P.; Brennand, J. P.

    1985-01-01

    ELVEC computer program provides vehicle designer with simulation tool for detailed studies of electric and hybrid vehicle performance and cost. ELVEC simulates performance of user-specified electric or hybrid vehicle under user specified driving schedule profile or operating schedule. ELVEC performs vehicle design and life cycle cost analysis.

  16. Hybrid spread spectrum radio system

    DOEpatents

    Smith, Stephen F [London, TN; Dress, William B [Camas, WA

    2010-02-09

    Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

  17. Electric-hybrid-vehicle simulation

    NASA Astrophysics Data System (ADS)

    Pasma, D. C.

    The simulation of electric hybrid vehicles is to be performed using experimental data to model propulsion system components. The performance of an existing ac propulsion system will be used as the baseline for comparative purposes. Hybrid components to be evaluated include electrically and mechanically driven flywheels, and an elastomeric regenerative braking system.

  18. Expanding Discourse Repertoires with Hybridity

    ERIC Educational Resources Information Center

    Kelly, Gregory J.

    2012-01-01

    In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally…

  19. Hybrid Power Management

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis

    2005-01-01

    An engineering discipline denoted as hybrid power management (HPM) has emerged from continuing efforts to increase energy efficiency and reliability of hybrid power systems. HPM is oriented toward integration of diverse electric energy-generating, energy-storing, and energy-consuming devices in optimal configurations for both terrestrial and outer-space applications. The basic concepts of HPM are potentially applicable at power levels ranging from nanowatts to megawatts. Potential applications include terrestrial power-generation, terrestrial transportation, biotechnology, and outer-space power systems. Instances of this discipline at prior stages of development were reported (though not explicitly labeled as HPM) in three prior NASA Tech Briefs articles: "Ultracapacitors Store Energy in a Hybrid Electric Vehicle"(LEW-16876), Vol. 24, No. 4 (April 2000), page 63; "Photovoltaic Power Station With Ultracapacitors for Storage" (LEW-17177), Vol. 27, No. 8 (August 2003), page 38; and "Flasher Powered by Photovoltaic Cells and Ultracapacitors" (LEW-17246), Vol. 24, No. 10 (October 2003), page 37. As the titles of the cited articles indicate, the use of ultracapacitors as energy-storage devices lies at the heart of HPM. An ultracapacitor is an electrochemical energy-storage device, but unlike in a conventional rechargeable electrochemical cell or battery, chemical reactions do not take place during operation. Instead, energy is stored electrostatically at an electrode/electrolyte interface. The capacitance per unit volume of an ultracapacitor is much greater than that of a conventional capacitor because its electrodes have much greater surface area per unit volume and the separation between the electrodes is much smaller. Power-control circuits for ultracapacitors can be simpler than those for batteries, for two reasons: (1) Because of the absence of chemical reactions, charge and discharge currents can be greater than those in batteries, limited only by the electrical

  20. Molecular evidence for hybridization in Colias (Lepidoptera: Pieridae): are Colias hybrids really hybrids?

    PubMed

    Dwyer, Heather E; Jasieniuk, Marie; Okada, Miki; Shapiro, Arthur M

    2015-07-01

    Gene flow and hybridization among species dramatically affect our understanding of the species as a biological unit, species relationships, and species adaptations. In North American Colias eurytheme and Colias eriphyle, there has been historical debate over the extent of hybridization occurring and the identity of phenotypically intermediate individuals as genetic hybrids. This study assesses the population structure of these two species to measure the extent of hybridization and the genetic identity of phenotypic intermediates as hybrids. Amplified fragment length polymorphism (AFLP) marker analysis was performed on 378 specimens collected from northern California and Nevada. Population structure was inferred using a Bayesian/Markov chain Monte Carlo method, which probabilistically assigns individuals to genetic clusters. Three genetic clusters provided the best fit for the data. C. eurytheme individuals were primarily assigned to two closely related clusters, and C. eriphyle individuals were mostly assigned to a third, more distantly related cluster. There appeared to be significant hybridization between the two species. Individuals of intermediate phenotype (putative hybrids) were found to be genetically indistinguishable from C. eriphyle, indicating that previous work based on the assumption that these intermediate forms are hybrids may warrant reconsideration. PMID:26306172

  1. Molecular evidence for hybridization in Colias (Lepidoptera: Pieridae): are Colias hybrids really hybrids?

    PubMed Central

    Dwyer, Heather E; Jasieniuk, Marie; Okada, Miki; Shapiro, Arthur M

    2015-01-01

    Gene flow and hybridization among species dramatically affect our understanding of the species as a biological unit, species relationships, and species adaptations. In North American Colias eurytheme and Colias eriphyle, there has been historical debate over the extent of hybridization occurring and the identity of phenotypically intermediate individuals as genetic hybrids. This study assesses the population structure of these two species to measure the extent of hybridization and the genetic identity of phenotypic intermediates as hybrids. Amplified fragment length polymorphism (AFLP) marker analysis was performed on 378 specimens collected from northern California and Nevada. Population structure was inferred using a Bayesian/Markov chain Monte Carlo method, which probabilistically assigns individuals to genetic clusters. Three genetic clusters provided the best fit for the data. C. eurytheme individuals were primarily assigned to two closely related clusters, and C. eriphyle individuals were mostly assigned to a third, more distantly related cluster. There appeared to be significant hybridization between the two species. Individuals of intermediate phenotype (putative hybrids) were found to be genetically indistinguishable from C. eriphyle, indicating that previous work based on the assumption that these intermediate forms are hybrids may warrant reconsideration. PMID:26306172

  2. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Stanley Miller; Rich Gebert; William Swanson

    1999-11-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses. The AHPC is currently being tested at the 2.7-MW scale at the Big Stone power station.

  3. Hybrid Electric Transit Bus

    NASA Technical Reports Server (NTRS)

    Viterna, Larry A.

    1997-01-01

    A government, industry, and university cooperative is developing an advanced hybrid electric city transit bus. Goals of this effort include doubling the fuel economy compared to current buses and reducing emissions to one-tenth of current EPA standards. Unique aspects of the vehicle's power system include the use of ultra-capacitors as an energy storage system, and a planned natural gas fueled turbogenerator developed from a small jet engine. Power from both the generator and energy storage system is provided to a variable speed electric motor attached to the rear axle. At over 15000 kg gross weight, this is the largest vehicle of its kind ever built using ultra-capacitor energy storage. This paper describes the overall power system architecture, the evolution of the control strategy, and its performance over industry standard drive cycles.

  4. Hybridized polymer matrix composites

    NASA Technical Reports Server (NTRS)

    Henshaw, J.

    1983-01-01

    Methods of improving the fire resistance of graphite epoxy composite laminates were investigated with the objective of reducing the volume of loose graphite fibers disseminated into the airstream as the result of a high intensity aircraft fuel fire. Improvements were sought by modifying the standard graphite epoxy systems without significantly negating their structural effectiveness. The modifications consisted primarily of an addition of a third constituent material such as glass fibers, glass flakes, carbon black in a glassy resin. These additions were designed to encourage coalescense of the graphite fibers and thereby reduce their aerodynamic float characteristics. A total of 38 fire tests were conducted on thin (1.0 mm) and thick (6.0 mm) hybrid panels.

  5. Hybrid powertrain controller

    DOEpatents

    Jankovic, Miroslava; Powell, Barry Kay

    2000-12-26

    A hybrid powertrain for a vehicle comprising a diesel engine and an electric motor in a parallel arrangement with a multiple ratio transmission located on the torque output side of the diesel engine, final drive gearing connecting drivably the output shaft of transmission to traction wheels of the vehicle, and an electric motor drivably coupled to the final drive gearing. A powertrain controller schedules fuel delivered to the diesel engine and effects a split of the total power available, a portion of the power being delivered by the diesel and the balance of the power being delivered by the motor. A shifting schedule for the multiple ratio transmission makes it possible for establishing a proportional relationship between accelerator pedal movement and torque desired at the wheels. The control strategy for the powertrain maintains drivability of the vehicle that resembles drivability of a conventional spark ignition vehicle engine powertrain while achieving improved fuel efficiency and low exhaust gas emissions.

  6. Hybrid powertrain system

    DOEpatents

    Grillo, Ricardo C.; O'Neil, Walter K.; Preston, David M.

    2005-09-20

    A hybrid powertrain system is provided that includes a first prime mover having a rotational output, a second prime mover having a rotational output, and a transmission having a main shaft supporting at least two main shaft gears thereon. The transmission includes a first independent countershaft drivingly connected to the first prime mover and including at least one ratio gear supported thereon that meshes with a respective main shaft gear. A second independent countershaft is drivingly connected to the second prime mover and includes at least one ratio gear supported thereon that meshes with a respective main shaft gear. The ratio gears on the first and second countershafts cooperate with the main shaft gears to provide at least one gear ratio between the first and second countershafts and the main shaft. A shift control mechanism selectively engages and disengages the first and second countershafts for rotation with the main shaft.

  7. Hybrid Heat Exchangers

    NASA Technical Reports Server (NTRS)

    Tu, Jianping Gene; Shih, Wei

    2010-01-01

    A hybrid light-weight heat exchanger concept has been developed that uses high-conductivity carbon-carbon (C-C) composites as the heat-transfer fins and uses conventional high-temperature metals, such as Inconel, nickel, and titanium as the parting sheets to meet leakage and structural requirements. In order to maximize thermal conductivity, the majority of carbon fiber is aligned in the fin direction resulting in 300 W/m.K or higher conductivity in the fin directions. As a result of this fiber orientation, the coefficient of thermal expansion (CTE) of the C-C composite in both non-fiber directions matches well with the CTE of various high-temperature metal alloys. This allows the joining of fins and parting sheets by using high-temperature braze alloys.

  8. Recognition Using Hybrid Classifiers.

    PubMed

    Osadchy, Margarita; Keren, Daniel; Raviv, Dolev

    2016-04-01

    A canonical problem in computer vision is category recognition (e.g., find all instances of human faces, cars etc., in an image). Typically, the input for training a binary classifier is a relatively small sample of positive examples, and a huge sample of negative examples, which can be very diverse, consisting of images from a large number of categories. The difficulty of the problem sharply increases with the dimension and size of the negative example set. We propose to alleviate this problem by applying a "hybrid" classifier, which replaces the negative samples by a prior, and then finds a hyperplane which separates the positive samples from this prior. The method is extended to kernel space and to an ensemble-based approach. The resulting binary classifiers achieve an identical or better classification rate than SVM, while requiring far smaller memory and lower computational complexity to train and apply. PMID:26959677

  9. Hybrid Natural Inflation

    NASA Astrophysics Data System (ADS)

    Ross, Graham G.; Germán, Gabriel; Vázquez, J. Alberto

    2016-05-01

    We construct two simple effective field theory versions of Hybrid Natural Inflation (HNI) that illustrate the range of its phenomenological implications. The resulting inflationary sector potential, V = Δ4(1 + acos( ϕ/f)), arises naturally, with the inflaton field a pseudo-Nambu-Goldstone boson. The end of inflation is triggered by a waterfall field and the conditions for this to happen are determined. Also of interest is the fact that the slow-roll parameter ɛ (and hence the tensor r) is a non-monotonic function of the field with a maximum where observables take universal values that determines the maximum possible tensor to scalar ratio r. In one of the models the inflationary scale can be as low as the electroweak scale. We explore in detail the associated HNI phenomenology, taking account of the constraints from Black Hole production, and perform a detailed fit to the Planck 2015 temperature and polarisation data.

  10. Hybrid community energy systems.

    SciTech Connect

    Jody, B. J.; Daniels, E. J.; Karvelas, D. E.; Energy Systems

    2000-01-01

    The availability of efficient, economical, and reliable energy supplies can help attract industry and commercial businesses to a municipality or a region. Efficient use of energy can also improve the air quality and reduce pollution. Therefore, municipalities should explore and encourage the development and implementation of efficient energy systems. Integrated hybrid energy systems can be designed to meet the total energy requirements of large and small communities. These systems can yield significant energy and cost savings when compared with independent systems serving individual units or when compared with the conventional practice of buying power from a utility and producing thermal energy on-site. To maximize energy and cost savings, the design engineer should look beyond the conventional when designing such systems.

  11. Hybrid vehicle control

    SciTech Connect

    Shallvari, Iva; Velnati, Sashidhar; DeGroot, Kenneth P.

    2015-07-28

    A method and apparatus for heating a catalytic converter's catalyst to an efficient operating temperature in a hybrid electric vehicle when the vehicle is in a charge limited mode such as e.g., the charge depleting mode or when the vehicle's high voltage battery is otherwise charge limited. The method and apparatus determine whether a high voltage battery of the vehicle is incapable of accepting a first amount of charge associated with a first procedure to warm-up the catalyst. If it is determined that the high voltage battery is incapable of accepting the first amount of charge, a second procedure with an acceptable amount of charge is performed to warm-up the catalyst.

  12. Hybrid Systems Diagnosis

    NASA Technical Reports Server (NTRS)

    McIlraith, Sheila; Biswas, Gautam; Clancy, Dan; Gupta, Vineet

    2005-01-01

    This paper reports on an on-going Project to investigate techniques to diagnose complex dynamical systems that are modeled as hybrid systems. In particular, we examine continuous systems with embedded supervisory controllers that experience abrupt, partial or full failure of component devices. We cast the diagnosis problem as a model selection problem. To reduce the space of potential models under consideration, we exploit techniques from qualitative reasoning to conjecture an initial set of qualitative candidate diagnoses, which induce a smaller set of models. We refine these diagnoses using parameter estimation and model fitting techniques. As a motivating case study, we have examined the problem of diagnosing NASA's Sprint AERCam, a small spherical robotic camera unit with 12 thrusters that enable both linear and rotational motion.

  13. Hybrid Filter Membrane

    NASA Technical Reports Server (NTRS)

    Laicer, Castro; Rasimick, Brian; Green, Zachary

    2012-01-01

    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  14. Hybrid multitarget tracking system

    NASA Astrophysics Data System (ADS)

    Subramanian, Aswinikumar; Hassebrook, Laurence G.; Ghosal, Sugata; Kim, Michael

    1992-11-01

    A common function for human being is to detect the movement of an object against a stationary background and then to lock on to and trace its motion. This natural process becomes very tedious in industrial or military environments where the database of images to be searched is huge or where the function is to be repeated continuously. Thus automation can assist people carrying out such tasks. This is the case in security systems, military reconnaissance, military targeting, aircraft tracking, assembly line manufacturing systems, and quality control. We present a hybrid system to do such tasks. The technique is simulated on computer using numerical algorithms and is successful under many situations. For implementation an ideal system using optical components is presented. This hybrid system employs three main subsystems which are combined in such a way as to compensate for each other's drawbacks yet enhance each other's virtues. The first system is a velocity correlation system which correlates two adjacent frames in a sequence of image frames. The resultant velocity correlations are searched to find the potential velocity profiles at which an object may be moving. These velocity profiles are then processed by the multi-frame mean subsystem which performs a geometric (or arithmetic mean) operation on the image frames. These frames are displaced by the selected velocity profiles and thereby aligning the object in the given frames for detection. Algorithms have been developed and tested to perform this technique on selected databases. Also algorithms to synthesize test images have been developed and the results are presented.

  15. Antibacterial Biomimetic Hybrid Films

    PubMed Central

    Ferrer, M. Carme Coll; Hickok, Noreen J.; Eckmann, David M.; Composto, Russell J.

    2012-01-01

    In this work, we present a novel method to prepare a hybrid coating based on dextran grafted to a substrate and embedded with silver nanoparticles (Ag NPs). First, the Ag NPs are synthesized in situ in the presence of oxidized dextran in solution. Second, the oxidized dextran is exposed to an amine functionalized surface resulting in the simultaneous grafting of dextran and the trapping of Ag NPs within the layer. The NP loading is controlled by the concentration of silver nitrate, which is 2 mM (DEX-Ag2) and 5 mM (DEX-Ag5). The dried film thickness increases with silver nitrate concentration from 2 nm for dextran to 7 nm and 12 nm for DEX-Ag2 and DEX-Ag5, respectively. The grafted dextran film displays features with a diameter and height of ~ 50 nm and 2 nm, respectively. For the DEX-Ag2 and DEX-Ag5, the dextran features as well as individual Ag NPs (~ 5 nm) and aggregates of Ag NPs are observed. Larger and more irregular aggregates are observed for DEX-Ag5. Overall, the Ag NPs are embedded in the dextran film as suggested by AFM and UVO studies. In terms of its antimicrobial activity, DEX-Ag2 resists bacterial adhesion to a greater extent than DEX-Ag5, which in turn is better than dextran and silicon. Because these antibacterial hybrid coatings can be grafted to a variety of surfaces, many biomedical applications can be envisioned, ranging from coating implants to catheters. PMID:23807896

  16. Nonminimally coupled hybrid inflation

    SciTech Connect

    Koh, Seoktae; Minamitsuji, Masato

    2011-02-15

    We discuss the hybrid inflation model where the inflaton field is nonminimally coupled to gravity. In the Jordan frame, the potential contains {phi}{sup 4} term as well as terms in the original hybrid inflation model. In our model, inflation can be classified into the type (I) and the type (II). In the type (I), inflation is terminated by the tachyonic instability of the waterfall field, while in the type (II) by the violation of slow-roll conditions. In our model, the reheating takes place only at the true minimum and even in the case (II) finally the tachyonic instability occurs after the termination of inflation. For a negative nonminimal coupling, inflation takes place in the vacuum-dominated region, in the large field region, or near the local minimum/maximum. Inflation in the vacuum-dominated region becomes either the type (I) or (II), resulting in a blue or red spectrum of the curvature perturbations, respectively. Inflation around the local maximum can be either the type (I) or the type (II), which results in the red spectrum of the curvature perturbations, while around the local minimum it must be the type (I), which results in the blue spectrum. In the large field region, to terminate inflation, potential in the Einstein frame must be positively tilted, always resulting in the red spectrum. We then numerically solve the equations of motion to investigate the whole dynamics of inflaton and confirm that the spectrum of curvature perturbations changes from red to blue ones as scales become smaller.

  17. Ball Aerospace Hybrid Space Cryocoolers

    NASA Astrophysics Data System (ADS)

    Gully, W.; Glaister, D. S.; Hendershott, P.; Kotsubo, V.; Lock, J. S.; Marquardt, E.

    2008-03-01

    This paper describes the design, development, testing, and performance at Ball Aerospace of a long-life hybrid (combination of Stirling and Joule-Thomson [J-T] thermodynamic cycles) space cryocooler. Hybrid coolers are synergistic combinations of two thermodynamic cycles that combine advantages of each cycle to yield overall improved performance. Hybrid cooler performance advantages include: 1) load leveling of large heat loads; 2) remote cryogenic cooling with very low to negligible induced vibration and jitter; 3) very low redundant (off state) cooler penalties; 4) high power efficiency, especially at low temperatures; and 5) simplified system integration with capability to cross gimbals and no need for thermal straps or switches. Ball Aerospace is currently developing several different hybrid cooler systems. The 35 K hybrid cooler provides 2.0 W at 35 K and 8.5 W at 85 K with an emphasis on load leveling of high transient heat loads and remote, low vibration cooling. The 10 K hybrid cooler provides 200 mW at 10 K, 700 mW at 15 K, and 10.7 W at 85 K with an emphasis on power efficiency. In addition, Ball Aerospace built and tested a complete hybrid cooler that met the requirements of the JWST Mid-Infrared Instrument (MIRI) cooler including providing 80 mW at 6 K and 100 mW at 18 K for a total system (28 V) power of 310 W.

  18. Hybridization increases invasive knotweed success

    PubMed Central

    Parepa, Madalin; Fischer, Markus; Krebs, Christine; Bossdorf, Oliver

    2014-01-01

    Hybridization is one of the fundamental mechanisms by which rapid evolution can occur in exotic species. If hybrids show increased vigour, this could significantly contribute to invasion success. Here, we compared the success of the two invasive knotweeds, Fallopia japonica and F. sachalinensis, and their hybrid, F. × bohemica, in competing against experimental communities of native plants. Using plant material from multiple clones of each taxon collected across a latitudinal gradient in Central Europe, we found that knotweed hybrids performed significantly better in competition with a native community and that they more strongly reduced the growth of the native plants. One of the parental species, F. sachalinensis, regenerated significantly less well from rhizomes, and this difference disappeared if activated carbon was added to the substrate, which suggests allelopathic inhibition of F. sachalinensis regeneration by native plants. We found substantial within-taxon variation in competitive success in all knotweed taxa, but variation was generally greatest in the hybrid. Interestingly, there was also significant variation within the genetically uniform F. japonica, possibly reflecting epigenetic differences. Our study shows that invasive knotweed hybrids are indeed more competitive than their parents and that hybridization increased the invasiveness of the exotic knotweed complex. PMID:24665343

  19. Hybrid deorbit motor design feasibility

    NASA Technical Reports Server (NTRS)

    Hastings, Joseph H.

    1993-01-01

    This paper addresses the feasibility of using a hybrid rocket motor to deorbit the large booster stage of the proposed NLS. A hybrid motor was of interest because it could utilize the residual low pressure Gox from the boosters main engine Lox tank. The resulting study determines that the concept would be feasible and should be given further consideration. Also, a preliminary design for a deorbit motor was proposed which would weigh much less than an equivalent hypergolic system. The hybrid deorbit concept and design has the potential of yielding a simpler cost effective system that could also be applicable to future launch systems with similar missions.

  20. Hybrid deorbit motor design feasibility

    NASA Astrophysics Data System (ADS)

    Hastings, Joseph H.

    1993-06-01

    This paper addresses the feasibility of using a hybrid rocket motor to deorbit the large booster stage of the proposed NLS. A hybrid motor was of interest because it could utilize the residual low pressure Gox from the boosters main engine Lox tank. The resulting study determines that the concept would be feasible and should be given further consideration. Also, a preliminary design for a deorbit motor was proposed which would weigh much less than an equivalent hypergolic system. The hybrid deorbit concept and design has the potential of yielding a simpler cost effective system that could also be applicable to future launch systems with similar missions.

  1. Hybrid Vehicle Program. Final report

    SciTech Connect

    1984-06-01

    This report summarizes the activities on the Hybrid Vehicle Program. The program objectives and the vehicle specifications are reviewed. The Hybrid Vehicle has been designed so that maximum use can be made of existing production components with a minimum compromise to program goals. The program status as of the February 9-10 Hardware Test Review is presented, and discussions of the vehicle subsystem, the hybrid propulsion subsystem, the battery subsystem, and the test mule programs are included. Other program aspects included are quality assurance and support equipment. 16 references, 132 figures, 47 tables.

  2. Hybrid Bearing Prognostic Test Rig

    NASA Technical Reports Server (NTRS)

    Dempsey, Paula J.; Certo, Joseph M.; Handschuh, Robert F.; Dimofte, Florin

    2005-01-01

    The NASA Glenn Research Center has developed a new Hybrid Bearing Prognostic Test Rig to evaluate the performance of sensors and algorithms in predicting failures of rolling element bearings for aeronautics and space applications. The failure progression of both conventional and hybrid (ceramic rolling elements, metal races) bearings can be tested from fault initiation to total failure. The effects of different lubricants on bearing life can also be evaluated. Test conditions monitored and recorded during the test include load, oil temperature, vibration, and oil debris. New diagnostic research instrumentation will also be evaluated for hybrid bearing damage detection. This paper summarizes the capabilities of this new test rig.

  3. Nanofluidic mixing via hybrid surface

    SciTech Connect

    Ye, Ziran; Li, Shunbo; Zhou, Bingpu; Hui, Yu Sanna; Shen, Rong; Wen, Weijia

    2014-10-20

    We report the design and fabrication of the nanofluidic mixer comprising hybrid hydrophobic/hydrophilic micro-patterns on the top and bottom walls of the nanochannel. The unique feature of such mixer is that, without any geometric structure inside the nanochannel, the mixing can be realized solely by the hybrid surfaces. Besides, the mixing length in nanomixer has been significantly shortened comparing to micromixer. We attribute the mixing achievement to be caused by the convection and chaotic flows of two fluids along the hybrid surface due to the large surface-to-volume ratio of the nanochannel.

  4. Triplex in-situ hybridization

    DOEpatents

    Fresco, Jacques R.; Johnson, Marion D.

    2002-01-01

    Disclosed are methods for detecting in situ the presence of a target sequence in a substantially double-stranded nucleic acid segment, which comprises: a) contacting in situ under conditions suitable for hybridization a substantially double-stranded nucleic acid segment with a detectable third strand, said third strand being capable of hybridizing to at least a portion of the target sequence to form a triple-stranded structure, if said target sequence is present; and b) detecting whether hybridization between the third strand and the target sequence has occured.

  5. Hybrid codes: Methods and applications

    SciTech Connect

    Winske, D. ); Omidi, N. )

    1991-01-01

    In this chapter we discuss hybrid'' algorithms used in the study of low frequency electromagnetic phenomena, where one or more ion species are treated kinetically via standard PIC methods used in particle codes and the electrons are treated as a single charge neutralizing massless fluid. Other types of hybrid models are possible, as discussed in Winske and Quest, but hybrid codes with particle ions and massless fluid electrons have become the most common for simulating space plasma physics phenomena in the last decade, as we discuss in this paper.

  6. Hybrid Rocket Propulsion for Sounding Rocket Applications

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A discussion of the H-225K hybrid rocket motor, produced by the American Rocket Company, is given. The H-225K motor is presented in terms of the following topics: (1) hybrid rocket fundamentals; (2) hybrid characteristics; and (3) hybrid advantages.

  7. Hybrid Inflatable Pressure Vessel

    NASA Technical Reports Server (NTRS)

    Raboin, Jasen; Valle, Gerard D.; Edeen, Gregg; DeLaFuente, Horacio M.; Schneider, William C.; Spexarth, Gary R.; Johnson, Christopher J.; Pandya, Shalini

    2004-01-01

    Figure 1 shows a prototype of a large pressure vessel under development for eventual use as a habitable module for long spaceflight (e.g., for transporting humans to Mars). The vessel is a hybrid that comprises an inflatable shell attached to a rigid central structural core. The inflatable shell is, itself, a hybrid that comprises (1) a pressure bladder restrained against expansion by (2) a web of straps made from high-strength polymeric fabrics. On Earth, pressure vessels like this could be used, for example, as portable habitats that could be set up quickly in remote locations, portable hyperbaric chambers for treatment of decompression sickness, or flotation devices for offshore platforms. In addition, some aspects of the design of the fabric straps could be adapted to such other items as lifting straps, parachute straps, and automotive safety belts. Figure 2 depicts selected aspects of the design of a vessel of this type with a toroidal configuration. The bladder serves as an impermeable layer to keep air within the pressure vessel and, for this purpose, is sealed to the central structural core. The web includes longitudinal and circumferential straps. To help maintain the proper shape upon inflation after storage, longitudinal and circumferential straps are indexed together at several of their intersections. Because the web is not required to provide a pressure seal and the bladder is not required to sustain structural loads, the bladder and the web can be optimized for their respective functions. Thus, the bladder can be sealed directly to the rigid core without having to include the web in the seal substructure, and the web can be designed for strength. The ends of the longitudinal straps are attached to the ends of the rigid structural core by means of clevises. Each clevis pin is surrounded by a roller, around which a longitudinal strap is wrapped to form a lap seam with itself. The roller is of a large diameter chosen to reduce bending of the fibers in

  8. Hybrid 10 Clinical Trial

    PubMed Central

    Gantz, Bruce J.; Hansen, Marlan R.; Turner, Christopher W.; Oleson, Jacob J.; Reiss, Lina A.; Parkinson, Aaron J.

    2010-01-01

    Acoustic plus electric (electric-acoustic) speech processing has been successful in highlighting the important role of articulation information in consonant recognition in those adults that have profound high-frequency hearing loss at frequencies greater than 1500 Hz and less than 60% discrimination scores. Eighty-seven subjects were enrolled in an adult Hybrid multicenter Food and Drug Administration clinical trial. Immediate hearing preservation was accomplished in 85/87 subjects. Over time (3 months to 5 years), some hearing preservation was maintained in 91% of the group. Combined electric-acoustic processing enabled most of this group of volunteers to gain improved speech understanding, compared to their preoperative hearing, with bilateral hearing aids. Most have preservation of low-frequency acoustic hearing within 15 dB of their preoperative pure tone levels. Those with greater losses (> 30 dB) also benefited from the combination of electric-acoustic speech processing. Postoperatively, in the electric-acoustic processing condition, loss of low-frequency hearing did not correlate with improvements in speech perception scores in quiet. Sixteen subjects were identified as poor performers in that they did not achieve a significant improvement through electric-acoustic processing. A multiple regression analysis determined that 91% of the variance in the poorly performing group can be explained by the preoperative speech recognition score and duration of deafness. Signal-to-noise ratios for speech understanding in noise improved more than 9 dB in some individuals in the electric-acoustic processing condition. The relation between speech understanding in noise thresholds and residual low-frequency acoustic hearing is significant (r = 0.62; p < 0.05). The data suggest that, in general, the advantages gained for speech recognition in noise by preserving residual hearing exist, unless the hearing loss approaches profound levels. Preservation of residual low

  9. Real and Hybrid Atomic Orbitals.

    ERIC Educational Resources Information Center

    Cook, D. B.; Fowler, P. W.

    1981-01-01

    Demonstrates that the Schrodinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. (Author/SK)

  10. A hybrid Brayton engine concept

    NASA Technical Reports Server (NTRS)

    Six, L. D.; Elkins, R.

    1980-01-01

    A first generation open cycle Brayton engine concept for use in full scale solar module testing was defined. The concept extended to include solar/fossil hybrid capability. The combustion system defined for hybrid operation consists of a wide range combustor liner, a single airblast atomizer, an ignitor and a high-voltage ignition unit. Wide range combustor operation would be achieved through combining pilot and primary zones. The hybrid control mode and the solar only control mode are both based on the concept of maintaining constant turbine inlet temperature and varying the engine speed for part-power operation. In addition, the hybrid control concept will allow the operator to set a minimum thermal power input to the engine by setting a corresponding minimum engine speed. When the solar thermal power input falls below this minimum, fossil fuel would be utilized to augment the solar thermal power input.

  11. Optical signal processing: Hybrid success

    NASA Astrophysics Data System (ADS)

    Hayden, Michael

    2007-03-01

    Despite two decades of work geared towards improving the nonlinear optical properties of organic molecules, practical organic light modulators have not yet reached the market in large numbers. New organic-inorganic hybrid approaches may revolutionize the field.

  12. Optimizing hybrid spreading in metapopulations.

    PubMed

    Zhang, Changwang; Zhou, Shi; Miller, Joel C; Cox, Ingemar J; Chain, Benjamin M

    2015-01-01

    Epidemic spreading phenomena are ubiquitous in nature and society. Examples include the spreading of diseases, information, and computer viruses. Epidemics can spread by local spreading, where infected nodes can only infect a limited set of direct target nodes and global spreading, where an infected node can infect every other node. In reality, many epidemics spread using a hybrid mixture of both types of spreading. In this study we develop a theoretical framework for studying hybrid epidemics, and examine the optimum balance between spreading mechanisms in terms of achieving the maximum outbreak size. We show the existence of critically hybrid epidemics where neither spreading mechanism alone can cause a noticeable spread but a combination of the two spreading mechanisms would produce an enormous outbreak. Our results provide new strategies for maximising beneficial epidemics and estimating the worst outcome of damaging hybrid epidemics. PMID:25923411

  13. Optimizing Hybrid Spreading in Metapopulations

    PubMed Central

    Zhang, Changwang; Zhou, Shi; Miller, Joel C.; Cox, Ingemar J.; Chain, Benjamin M.

    2015-01-01

    Epidemic spreading phenomena are ubiquitous in nature and society. Examples include the spreading of diseases, information, and computer viruses. Epidemics can spread by local spreading, where infected nodes can only infect a limited set of direct target nodes and global spreading, where an infected node can infect every other node. In reality, many epidemics spread using a hybrid mixture of both types of spreading. In this study we develop a theoretical framework for studying hybrid epidemics, and examine the optimum balance between spreading mechanisms in terms of achieving the maximum outbreak size. We show the existence of critically hybrid epidemics where neither spreading mechanism alone can cause a noticeable spread but a combination of the two spreading mechanisms would produce an enormous outbreak. Our results provide new strategies for maximising beneficial epidemics and estimating the worst outcome of damaging hybrid epidemics. PMID:25923411

  14. Hybrid-Vehicle Transmission System

    NASA Technical Reports Server (NTRS)

    Lupo, G.; Dotti, G.

    1985-01-01

    Continuously-variable transmission system for hybrid vehicles couples internal-combustion engine and electric motor section, either individually or in parallel, to power vehicle wheels during steering and braking.

  15. Hybrid Fuel Cell Technology Overview

    SciTech Connect

    None available

    2001-05-31

    For the purpose of this STI product and unless otherwise stated, hybrid fuel cell systems are power generation systems in which a high temperature fuel cell is combined with another power generating technology. The resulting system exhibits a synergism in which the combination performs with an efficiency far greater than can be provided by either system alone. Hybrid fuel cell designs under development include fuel cell with gas turbine, fuel cell with reciprocating (piston) engine, and designs that combine different fuel cell technologies. Hybrid systems have been extensively analyzed and studied over the past five years by the Department of Energy (DOE), industry, and others. These efforts have revealed that this combination is capable of providing remarkably high efficiencies. This attribute, combined with an inherent low level of pollutant emission, suggests that hybrid systems are likely to serve as the next generation of advanced power generation systems.

  16. Damage of hybrid composite laminates

    NASA Astrophysics Data System (ADS)

    Haery, Haleh A.; Kim, Ho Sung

    2013-08-01

    Hybrid laminates consisting of woven glass fabric/epoxy composite plies and woven carbon fabric/epoxy composite plies are studied for fatigue damage and residual strength. A theoretical framework based on the systems approach is proposed as a guide to deal with the complexity involving uncertainties and a large number of variables in the hybrid composite system. A relative damage sensitivity factor expression was developed for quantitative comparisons between non-hybrid and hybrid composites. Hypotheses derived from the theoretical framework were tested and verified. The first hypothesis was that the difference between two different sets of properties produces shear stress in interface between carbon fibre reinforced plastics (CRP) and glass fibre reinforced plastics (GRP), and eventually become a source for CRP/GRP interfacial delamination or longitudinal cracking. The second hypothesis was that inter-fibre bundle delamination occurs more severely to CRP sub-system than GRP sub-system.

  17. A hybrid base isolation system

    SciTech Connect

    Hart, G.C.; Lobo, R.F.; Srinivasan, M.; Asher, J.W.

    1995-12-01

    This paper proposes a new analysis procedure for hybrid base isolation buildings when considering the displacement response of a base isolated building to wind loads. The system is considered hybrid because of the presence of viscous dampers in the building above the isolator level. The proposed analysis approach incorporates a detailed site specific wind study combined with a dynamic nonlinear analysis of the building response.

  18. Real and hybrid atomic orbitals

    NASA Astrophysics Data System (ADS)

    Cook, D. B.; Fowler, P. W.

    1981-09-01

    It is shown that the Schrödinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. Thus the real and hybrid atomic orbitals have as sound a pedigree as the more familiar complex orbitals based on the separation of the Schrödinger equation in spherical polar coordinates.

  19. Forced Oscillations for Hybrid Systems

    NASA Astrophysics Data System (ADS)

    Cheshankov, B.

    2009-11-01

    The hybrid system in the paper means a mechanical system which consists from two parts with different structure—a part with distributed parameters and a part with discrete parameters. More concrete the forced longitudinal oscillations of a rod connected with a simple oscillator are considered. The oscillations of the separate parts of the system are very well known. It turned out that the oscillations of this hybrid system propose some difficulties when investigating. The paper proposes an approach to overcome these difficulties.

  20. Hybrid particles and associated methods

    DOEpatents

    Fox, Robert V; Rodriguez, Rene; Pak, Joshua J; Sun, Chivin

    2015-02-10

    Hybrid particles that comprise a coating surrounding a chalcopyrite material, the coating comprising a metal, a semiconductive material, or a polymer; a core comprising a chalcopyrite material and a shell comprising a functionalized chalcopyrite material, the shell enveloping the core; or a reaction product of a chalcopyrite material and at least one of a reagent, heat, and radiation. Methods of forming the hybrid particles are also disclosed.

  1. Hybrid superconductor magnet bearings

    SciTech Connect

    Chu, W.

    1995-04-01

    Hybrid superconductor magnet bearings (HSMB`s) utilize high temperature superconductors (HTS`s) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS`s, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, the authors present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  2. Hybrid superconductor magnet bearings

    NASA Astrophysics Data System (ADS)

    Chu, Wei-Kan

    1995-04-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  3. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Stanley J. Miller; Grant L. Schelkoph; Grant E. Dunham

    2000-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and recollection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hour parametric tests and 100-hour proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency.

  4. Hybrid Power Management (HPM)

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2007-01-01

    The NASA Glenn Research Center s Avionics, Power and Communications Branch of the Engineering and Systems Division initiated the Hybrid Power Management (HPM) Program for the GRC Technology Transfer and Partnership Office. HPM is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors and fuel cells. HPM has extremely wide potential. Applications include power generation, transportation systems, biotechnology systems, and space power systems. HPM has the potential to significantly alleviate global energy concerns, improve the environment, and stimulate the economy. One of the unique power devices being utilized by HPM for energy storage is the ultracapacitor. An ultracapacitor is an electrochemical energy storage device, which has extremely high volumetric capacitance energy due to high surface area electrodes, and very small electrode separation. Ultracapacitors are a reliable, long life, maintenance free, energy storage system. This flexible operating system can be applied to all power systems to significantly improve system efficiency, reliability, and performance. There are many existing and conceptual applications of HPM.

  5. Hybrid power source

    DOEpatents

    Singh, Harmohan N.

    2012-06-05

    A hybrid power system is comprised of a high energy density element such as a fuel-cell and high power density elements such as a supercapacitor banks. A DC/DC converter electrically connected to the fuel cell and converting the energy level of the energy supplied by the fuel cell. A first switch is electrically connected to the DC/DC converter. First and second supercapacitors are electrically connected to the first switch and a second switch. A controller is connected to the first switch and the second switch, monitoring charge levels of the supercapacitors and controls the switching in response to the charge levels. A load is electrically connected to the second switch. The first switch connects the DC/DC converter to the first supercapacitor when the second switch connects the second supercapacitor to the load. The first switch connects the DC/DC converter to the second supercapacitor when the second switch connects the first supercapacitor to the load.

  6. Hybrid superconductor magnet bearings

    NASA Technical Reports Server (NTRS)

    Chu, Wei-Kan

    1995-01-01

    Hybrid superconductor magnet bearings (HSMB's) utilize high temperature superconductors (HTS's) together with permanent magnets to form a frictionless interface between relatively rotating parts. They are low mass, stable, and do not incur expenditure of energy during normal operation. There is no direct physical contact between rotor and stator, and hence there is no wear and tear. However, just as any other applications of HTS's, it requires a very cold temperature to function. Whereas this might be perceived as a disadvantage on earth, it is of no great concern in space or on the moon. To astronomers, the moon is an excellent site for an observatory, but the cold and dusty vacuum environment on the moon precludes the use of mechanical bearings on the telescope mounts. Furthermore, drive mechanisms with very fine steps, and hence bearings with extremely low friction are needed to track a star from the moon, because the moon rotates very slowly. All aspects considered, the HSMB is about the only candidate that fits in naturally. Here, we present a design for one such bearing, capable of supporting a telescope that weighs about 3 lbs on Earth.

  7. Metallographic in situ hybridization.

    PubMed

    Powell, Richard D; Pettay, James D; Powell, William C; Roche, Patrick C; Grogan, Thomas M; Hainfeld, James F; Tubbs, Raymond R

    2007-08-01

    Metallographic methods, in which a target is visualized using a probe or antibody that deposits metal selectively at its binding site, offers many advantages for bright-field in situ hybridization (ISH) detection as well as for other labeling and detection methods. Autometallographically enhanced gold labeling procedures have demonstrated higher sensitivity than conventional enzyme chromogens. Enzyme metallography, a novel procedure in which an enzymatic probe is used to deposit metal directly from solution, has been used to develop bright-field ISH methods for HER2 gene determination in breast cancer and other biopsy specimens. It provides the highest level of sensitivity and resolution, both for visualizing endogenous gene copies in nonamplified tissues and for resolving multiple gene copies to allow copy enumeration in amplified tissues without the need for oil immersion or fluorescence optics. An automated enzyme metallography procedure, silver ISH, has been developed for use in slide-staining instruments. Metallographic staining also provides excellent results for immunohistochemistry and may be combined with other staining procedures for the simultaneous detection of more than one gene or combinations of genes and proteins. PMID:17640553

  8. Hybrid Arrays for Chemical Sensing

    NASA Astrophysics Data System (ADS)

    Kramer, Kirsten E.; Rose-Pehrsson, Susan L.; Johnson, Kevin J.; Minor, Christian P.

    In recent years, multisensory approaches to environment monitoring for chemical detection as well as other forms of situational awareness have become increasingly popular. A hybrid sensor is a multimodal system that incorporates several sensing elements and thus produces data that are multivariate in nature and may be significantly increased in complexity compared to data provided by single-sensor systems. Though a hybrid sensor is itself an array, hybrid sensors are often organized into more complex sensing systems through an assortment of network topologies. Part of the reason for the shift to hybrid sensors is due to advancements in sensor technology and computational power available for processing larger amounts of data. There is also ample evidence to support the claim that a multivariate analytical approach is generally superior to univariate measurements because it provides additional redundant and complementary information (Hall, D. L.; Linas, J., Eds., Handbook of Multisensor Data Fusion, CRC, Boca Raton, FL, 2001). However, the benefits of a multisensory approach are not automatically achieved. Interpretation of data from hybrid arrays of sensors requires the analyst to develop an application-specific methodology to optimally fuse the disparate sources of data generated by the hybrid array into useful information characterizing the sample or environment being observed. Consequently, multivariate data analysis techniques such as those employed in the field of chemometrics have become more important in analyzing sensor array data. Depending on the nature of the acquired data, a number of chemometric algorithms may prove useful in the analysis and interpretation of data from hybrid sensor arrays. It is important to note, however, that the challenges posed by the analysis of hybrid sensor array data are not unique to the field of chemical sensing. Applications in electrical and process engineering, remote sensing, medicine, and of course, artificial

  9. Fiber reinforced hybrid phenolic foam

    NASA Astrophysics Data System (ADS)

    Desai, Amit

    Hybrid composites in recent times have been developed by using more than one type of fiber reinforcement to bestow synergistic properties of the chosen filler and matrix and also facilitating the design of materials with specific properties matched to end use. However, the studies for hybrid foams have been very limited because of problems related to fiber dispersion in matrix, non uniform mixing due to presence of more than one filler and partially cured foams. An effective approach to synthesize hybrid phenolic foam has been proposed and investigated here. Hybrid composite phenolic foams were reinforced with chopped glass and aramid fibers in varied proportions. On assessing mechanical properties in compression and shear several interesting facts surfaced but overall hybrid phenolic foams exhibited a more graceful failure, greater resistance to cracking and were significantly stiffer and stronger than foams with only glass and aramid fibers. The optimum fiber ratio for the reinforced hybrid phenolic foam system was found to be 1:1 ratio of glass to aramid fibers. Also, the properties of hybrid foam were found to deviate from rule of mixture (ROM) and thus the existing theories of fiber reinforcement fell short in explaining their complex behavior. In an attempt to describe and predict mechanical behavior of hybrid foams a statistical design tool using analysis of variance technique was employed. The utilization of a statistical model for predicting foam properties was found to be an appropriate tool that affords a global perspective of the influence of process variables such as fiber weight fraction, fiber length etc. on foam properties (elastic modulus and strength). Similar approach could be extended to study other fiber composite foam systems such as polyurethane, epoxy etc. and doing so will reduce the number of experimental iterations needed to optimize foam properties and identify critical process variables. Diffusivity, accelerated aging and flammability

  10. Hybridization in a warmer world

    PubMed Central

    Chunco, Amanda J

    2014-01-01

    Climate change is profoundly affecting the evolutionary trajectory of individual species and ecological communities, in part through the creation of novel species assemblages. How climate change will influence competitive interactions has been an active area of research. Far less attention, however, has been given to altered reproductive interactions. Yet, reproductive interactions between formerly isolated species are inevitable as populations shift geographically and temporally as a result of climate change, potentially resulting in introgression, speciation, or even extinction. The susceptibility of hybridization rates to anthropogenic disturbance was first recognized in the 1930s. To date, work on anthropogenically mediated hybridization has focused primarily on either physical habitat disturbance or species invasion. Here, I review recent literature on hybridization to identify how ecological responses to climate change will increase the likelihood of hybridization via the dissolution of species barriers maintained by habitat, time, or behavior. Using this literature, I identify several cases where novel hybrid zones have recently formed, likely as a result of changing climate. Future research should focus on identifying areas and taxonomic groups where reproductive species interactions are most likely to be influenced by climate change. Furthermore, a better understanding of the evolutionary consequences of climate-mediated secondary contact is urgently needed. Paradoxically, hybridization is both a major conservation concern and an important source of novel genetic and phenotypic variation. Hybridization may therefore both contribute to increasing rates of extinction and stimulate the creation of novel phenotypes that will speed adaptation to novel climates. Predicting which result will occur following secondary contact will be an important contribution to conservation for many species. PMID:24963394

  11. Fission fusion hybrids- recent progress

    NASA Astrophysics Data System (ADS)

    Kotschenreuther, M.; Valanju, P.; Mahajan, S.; Covele, B.

    2012-03-01

    Fission-fusion hybrids enjoy unique advantages for addressing long standing societal acceptability issues of nuclear fission power, and can do this at a much lower level of technical development than a competitive fusion power plant- so it could be a nearer term application. For waste incineration, hybrids can burn intransigent transuranic residues (with the long lived biohazard) from light water reactors (LWRs) with far fewer hybrid reactors than a comparable system within the realm of fission alone. For fuel production, hybrids can produce fuel for ˜4 times as many LWRs with NO fuel reprocessing. For both waste incineration or fuel production, the most severe kind of nuclear accident- runaway criticality- can be excluded, unlike either fast reactors or typical accelerator based reactors. The proliferation risks for hybrid fuel production are, we strongly believe, far less than any other fuel production method, including today's gas centrifuges. US Thorium reserves could supply the entire US electricity supply for centuries. The centerpiece of the fuel cycle is a high power density Compact Fusion Neutron Source (major+minor radius ˜ 2.5-3.5 m), which is made feasible by the super-X divertor.

  12. Hybrid metrology implementation: server approach

    NASA Astrophysics Data System (ADS)

    Osorio, Carmen; Timoney, Padraig; Vaid, Alok; Elia, Alex; Kang, Charles; Bozdog, Cornel; Yellai, Naren; Grubner, Eyal; Ikegami, Toru; Ikeno, Masahiko

    2015-03-01

    Hybrid metrology (HM) is the practice of combining measurements from multiple toolset types in order to enable or improve metrology for advanced structures. HM is implemented in two phases: Phase-1 includes readiness of the infrastructure to transfer processed data from the first toolset to the second. Phase-2 infrastructure allows simultaneous transfer and optimization of raw data between toolsets such as spectra, images, traces - co-optimization. We discuss the extension of Phase-1 to include direct high-bandwidth communication between toolsets using a hybrid server, enabling seamless fab deployment and further laying the groundwork for Phase-2 high volume manufacturing (HVM) implementation. An example of the communication protocol shows the information that can be used by the hybrid server, differentiating its capabilities from that of a host-based approach. We demonstrate qualification and production implementation of the hybrid server approach using CD-SEM and OCD toolsets for complex 20nm and 14nm applications. Finally we discuss the roadmap for Phase-2 HM implementation through use of the hybrid server.

  13. Intercalated hybrid graphite fiber composite

    NASA Technical Reports Server (NTRS)

    Gaier, James R. (Inventor)

    1993-01-01

    The invention is directed to a highly conductive lightweight hybrid material and methods of producing the same. The hybrid composite is obtained by weaving strands of a high strength carbon or graphite fiber into a fabric-like structure, depositing a layer of carbon onto the structure, heat treating the structure to graphitize the carbon layer, and intercalating the graphitic carbon layer structure. A laminate composite material useful for protection against lightning strikes comprises at least one layer of the hybrid material over at least one layer of high strength carbon or graphite fibers. The composite material of the present invention is compatible with matrix compounds, has a coefficient of thermal expansion which is the same as underlying fiber layers, and is resistant to galvanic corrosion in addition to being highly conductive. These materials are useful in the aerospace industry, in particular as lightning strike protection for airplanes.

  14. Additive Manufacturing of Hybrid Circuits

    NASA Astrophysics Data System (ADS)

    Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.

    2016-07-01

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  15. Genomic Networks of Hybrid Sterility

    PubMed Central

    Turner, Leslie M.; White, Michael A.; Tautz, Diethard; Payseur, Bret A.

    2014-01-01

    Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci (“Dobzhansky-Muller incompatibilities”). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven ‘hotspots,’ seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL—but not cis eQTL—were substantially lower when mapping was restricted to a ‘fertile’ subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is

  16. Helping HAN for hybrid rockets

    NASA Astrophysics Data System (ADS)

    Ramohalli, Kumar; Dowler, Warren

    1995-01-01

    Hydroxyl amine nitrate (HAN) is a powerful oxidizer for hybrid rocket flight motors. Miscible with water up to 95% by mass, it also has high density and has been extensively characterized for materials compatibility, safety, transportation, storage and handling. Before any serious attempt to use the proposed oxidizer in hybrids, though, the usual performance figures must first be obtained. The simplest are time-independent, equilibrium rocket performance numbers that include chamber temperature, temperature at the nozzle throat, and key species in the exhaust. These numbers must be followed by several other important performance evaluation, including burning rates, pressure dependence, susceptibility to instabilities and temperature sensitivity.

  17. Charge-qubit-atom hybrid

    NASA Astrophysics Data System (ADS)

    Yu, Deshui; Valado, María Martínez; Hufnagel, Christoph; Kwek, Leong Chuan; Amico, Luigi; Dumke, Rainer

    2016-04-01

    We investigate a hybrid system of a superconducting charge qubit interacting directly with a single neutral atom via electric dipole coupling. Interfacing of the macroscopic superconducting circuit with the microscopic atomic system is accomplished by varying the gate capacitance of the charge qubit. To achieve a strong interaction, we employ two Rydberg states with an electric-dipole-allowed transition, which alters the polarizability of the dielectric medium of the gate capacitor. Sweeping the gate voltage with different rates leads to a precise control of hybrid quantum states. Furthermore, we show a possible implementation of a universal two-qubit gate.

  18. PSEUDOVECTOR MESONS, HYBRIDS AND GLUEBALLS

    SciTech Connect

    L. BURAKOVSKY; P. PAGE

    2000-06-01

    The authors consider glueball-(hybrid) meson mixing for the low-lying four pseudovector states. The h{sub 1}{prime}(1380) decays dominantly to K*K with some presence in {rho}{pi} and {omega}{eta}. The newly observed h{sub 1}(1600) has a D- to S-wave width ratio to {omega}{eta} which makes its interpretation as a conventional meson unlikely. They predict the decay pattern of the isopartner conventional or hybrid meson b{sub 1}(1650). A notably narrow s{bar s} partner h{sub 1}{prime}(1810) is predicted.

  19. Heavy gravitino in hybrid inflation

    SciTech Connect

    Kawasaki, Masahiro; Kitajima, Naoya; Nakayama, Kazunori; Yanagida, Tsutomu T. E-mail: nk610@icrr.u-tokyo.ac.jp E-mail: tsutomu.tyanagida@ipmu.jp

    2013-06-01

    It is known that supersymmetric hybrid inflation model may require severe tunings on the initial condition for large gravitino mass of order 100 - 1000 TeV due to the constant term in the superpotential. We propose a modified hybrid inflation model, where the constant term is suppressed during inflation and generated after inflation by replacing a constant term with dynamical field. In this modified model, successful inflation consistent with large gravitino mass takes place without severe tunings on the initial condition. Constraint from cosmic strings is also relaxed.

  20. Hybrid biotic/abiotic nanofactory

    NASA Astrophysics Data System (ADS)

    Choi, H.-J.; Montemagno, C. D.

    2006-03-01

    In vitro biochemical synthesis is considered a major challenge in replicating cellular functions in engineered systems. Presented is the first nanosized hybrid factory where biochemical reactions take place resulting in the production of biomolecules. A cellular ATP synthesis process is reconstructed in vitro within a bubble architecture using engineered artificial organelles. This is the first introduction of biochemical synthesis from a multiprotein polymersome system and the demonstration of complex proteins' stable functionality in an artificial structure. This hybrid system is expected to have wide application in a number of fields ranging from the in vitro investigation of cellular metabolism to the synthesis of a new class of functional materials.

  1. Optical Hybrid Quantum Information Processing

    NASA Astrophysics Data System (ADS)

    Takeda, Shuntaro; Furusawa, Akira

    Historically, two complementary approaches to optical quantum information processing have been pursued: qubits and continuous-variables, each exploiting either particle or wave nature of light. However, both approaches have pros and cons. In recent years, there has been a significant progress in combining both approaches with a view to realizing hybrid protocols that overcome the current limitations. In this chapter, we first review the development of the two approaches with a special focus on quantum teleportation and its applications. We then introduce our recent research progress in realizing quantum teleportation by a hybrid scheme, and mention its future applications to universal and fault-tolerant quantum information processing.

  2. Hybrid combustion with metallized fuels

    NASA Technical Reports Server (NTRS)

    Yi, Jianwen; Wygle, Brian S.; Bates, Ronald W.; Jones, Michael D.; Ramohalli, Kumar

    1993-01-01

    A chemical method of adding certain catalysts to improve the degradation process of a solid fuel is discussed. Thermogravimetric (TGA) analysis used to study the fundamental degradation behavior of a typical hybrid fuel (HTPB) shows that high surface temperatures increase the degradation rate. Fuels were tested in a laboratory-scale experimental hybrid rocket and their behavior was compared to a baseline behavior of HTPB fuel regression rates. It was found that a small amount of metal powder added to the fuel can significantly increase the regression rates.

  3. Anisotropic flow in transport + hydrodynamics hybrid approaches

    NASA Astrophysics Data System (ADS)

    Petersen, Hannah

    2014-12-01

    This contribution to the focus issue covers anisotropic flow in hybrid approaches. The historical development of hybrid approaches and their impact on the interpretation of flow measurements is reviewed. The major ingredients of a hybrid approach and the transition criteria between transport and hydrodynamics are discussed. The results for anisotropic flow in (event-by-event) hybrid approaches are presented. Some hybrid approaches rely on hadronic transport for the late stages for the reaction (so called afterburner) and others employ transport approaches for the early non-equilibrium evolution. In addition, there are ‘full’ hybrid calculations where a fluid evolution is dynamically embedded in a transport simulation. After demonstrating the success of hybrid approaches at high Relativistic Heavy Ion Collider and Large Hadron Collider energies, existing hybrid caluclations for collective flow observables at lower beam energies are discussed and remaining challenges outlined.

  4. Hybrid power management system and method

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J. (Inventor)

    2007-01-01

    A system and method for hybrid power management. The system includes photovoltaic cells, ultracapacitors, and pulse generators. In one embodiment, the hybrid power management system is used to provide power for a highway safety flasher.

  5. Hybrid Power Management System and Method

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J. (Inventor)

    2008-01-01

    A system and method for hybrid power management. The system includes photovoltaic cells, ultracapacitors, and pulse generators. In one embodiment, the hybrid power management system is used to provide power for a highway safety flasher.

  6. Field errors in hybrid insertion devices

    SciTech Connect

    Schlueter, R.D.

    1995-02-01

    Hybrid magnet theory as applied to the error analyses used in the design of Advanced Light Source (ALS) insertion devices is reviewed. Sources of field errors in hybrid insertion devices are discussed.

  7. High Temperature Hybrid Elastomers

    NASA Astrophysics Data System (ADS)

    Drake, Kerry Anthony

    Conventional high temperature elastomers are produced by chain polymerization of olefinic or fluorinated olefinic monomers. Ultimate thermal stabilities are limited by backbone bond strengths, lower thermal stability of cross-link sites relative to backbone bonds, and depolymerization or "unzipping" at high temperatures. In order to develop elastomers with enhanced thermal stability, hybrid thermally cross-linkable polymers that consisted only of organic-inorganic and aromatic bonds were synthesized and evaluated. The addition of phenylethynyl or phenylacetylinic functional groups to these polymers resulted in conversion of the polymers into high temperature elastomers when cross-linked by thermal curing. Polyphenyoxydiphenylsilanes were synthesized via several different condensation reactions. Results of these synthetic reactions, which utilized both hydroquinone and biphenol as monomers, were systematically evaluated to determine the optimal synthetic conditions for subsequent endcapping reactions. It was determined that dichlorodiphenylsilane condensations with biphenol in toluene or THF were best suited for this work. Use of excess dichlorodiphenylsilane yielded polymers of appropriate molecular weights with terminal reactive chlorosilane groups that could be utilized for coupling with phenylethynyl reagents in a subsequent reaction. Two new synthetic routes were developed to endcap biphenoxysilanes with ethynyl containing substituents, to yield polymers with cross-linkable end groups. Endcapping by lithiumphenylacetylide and 4[(4-fluorophenylethynyl))phenol yielded two new polymers that could be thermally cross-linked on heating above 300 °C. Successful endcapping was verified chemically by 13C NMR, FTIR and Raman analysis. Exothermic peaks consistent with ethynyl curing reactions were observed in endcapped polymers by DSC. A new diacetylinic polymer was prepared through reaction of 4,4'-buta-1,3-diyne-1,4-diyldiphenol and dichlorodiphenylsilane. This

  8. Actuated Hybrid Mirror Telescope

    NASA Technical Reports Server (NTRS)

    Hickey, Gregory; Redding, David; Lowman, Andrew; Cohen, David; Ohara, Catherine

    2005-01-01

    The figure depicts the planned Actuated Hybrid Mirror Telescope (AHMT), which is intended to demonstrate a new approach to the design and construction of wide-aperture spaceborne telescopes for astronomy and Earth science. This technology is also appropriate for Earth-based telescopes. The new approach can be broadly summarized as using advanced lightweight mirrors that can be manufactured rapidly at relatively low cost. More specifically, it is planned to use precise replicated metallic nanolaminate mirrors to obtain the required high-quality optical finishes. Lightweight, dimensionally stable silicon carbide (SiC) structures will support the nanolaminate mirrors in the required surface figures. To enable diffraction- limited telescope performance, errors in surface figures will be corrected by use of mirror-shape-control actuators that will be energized, as needed, by a wave-front-sensing and control system. The concepts of nanolaminate materials and mirrors made from nanolaminate materials were discussed in several previous NASA Tech Briefs articles. Nanolaminates constitute a relatively new class of materials that can approach theoretical limits of stiffness and strength. Nanolaminate mirrors are synthesized by magnetron sputter deposition of metallic alloys and/or compounds on optically precise master surfaces to obtain optical-quality reflector surfaces backed by thin shell structures. As an integral part of the deposition process, a layer of gold that will constitute the reflective surface layer is deposited first, eliminating the need for a subsequent and separate reflective-coating process. The crystallographic textures of the nanolaminate will be controlled to optimize the performance of the mirror. The entire deposition process for making a nanolaminate mirror takes less than 100 hours, regardless of the mirror diameter. Each nanolaminate mirror will be bonded to its lightweight SiC supporting structure. The lightweight nanolaminate mirrors and Si

  9. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  10. Hybrid quantum information processing

    NASA Astrophysics Data System (ADS)

    Furusawa, Akira

    2013-03-01

    the other hand, the fidelity of CV QIP is not so high because perfect fidelity needs infinite energy, which comes from the infinite dimensionality of CV QIP. To overcome the difficulty, ``hybrid'' approach is proposed. In this approach, qubits are used as inputs for CV QIP. It is possible because qubits can be regarded as a special case of CVs. So, we can circumvent the infinite dimensionality problem of CV QIP by using qubits as the inputs. The basic example is qubit teleportation with a CV teleporter, where the qubit is a so-called ``dual-rail'' qubit with a single photon; c0 | 1 , 0 > +c1 | 0 , 1 > . We recently succeeded in creating time-bin qubits with single photons, and now we are working on the teleportation experiment with the technology developed for teleportation of highly nonclassical wave packets of light.

  11. The Hybrid Automobile and the Atkinson Cycle

    ERIC Educational Resources Information Center

    Feldman, Bernard J.

    2008-01-01

    The hybrid automobile is a strikingly new automobile technology with a number of new technological features that dramatically improve energy efficiency. This paper will briefly describe how hybrid automobiles work; what are these new technological features; why the Toyota Prius hybrid internal combustion engine operates on the Atkinson cycle…

  12. Sativa by falcata alfalfa hybrid variety trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has demonstrated that alfalfa (Medicago sativa L.) subsp. sativa by subsp. falcata hybrids showed heterosis. Limited work has been done examining these hybrids in a sward situation. The objective of this study was to produce sativa by falcata hybrids using Dairyland Seed Company’...

  13. Hybrid Doctoral Program: Innovative Practices and Partnerships

    ERIC Educational Resources Information Center

    Alvich, Dori; Manning, JoAnn; McCormick, Kathy; Campbell, Robert

    2012-01-01

    This paper reflects on how one mid-Atlantic University innovatively incorporated technology into the development of a hybrid doctoral program in educational leadership. The paper describes a hybrid doctoral degree program using a rigorous design; challenges of reworking a traditional syllabus of record to a hybrid doctoral program; the perceptions…

  14. Hybrid Computation at Louisiana State University.

    ERIC Educational Resources Information Center

    Corripio, Armando B.

    Hybrid computation facilities have been in operation at Louisiana State University since the spring of 1969. In part, they consist of an Electronics Associates, Inc. (EAI) Model 680 analog computer, an EAI Model 693 interface, and a Xerox Data Systems (XDS) Sigma 5 digital computer. The hybrid laboratory is used in a course on hybrid computation…

  15. Hybrid Cars Now, Fuel Cell Cars Later

    NASA Astrophysics Data System (ADS)

    Demirdöven, Nurettin; Deutch, John

    2004-08-01

    We compare the energy efficiency of hybrid and fuel cell vehicles as well as conventional internal combustion engines. Our analysis indicates that fuel cell vehicles using hydrogen from fossil fuels offer no significant energy efficiency advantage over hybrid vehicles operating in an urban drive cycle. We conclude that priority should be placed on hybrid vehicles by industry and government.

  16. 40 CFR 1036.525 - Hybrid engines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in CO2 emissions resulting from the power take-off operation as described in 40 CFR 1037.525. Use..., the rechargeable energy storage system (RESS) and the power electronics between the hybrid electric... part and/or 40 CFR part 1065. If you test hybrid engines using the SET, deactivate the hybrid...

  17. Using Hybrid Modeling to Develop Innovative Activities

    ERIC Educational Resources Information Center

    Lichtman, Brenda; Avans, Diana

    2005-01-01

    This article describes a hybrid activities model that physical educators can use with students in grades four and above to create virtually a limitless array of novel games. A brief introduction to the basic theory is followed by descriptions of some hybrid games. Hybrid games are typically the result of merging two traditional sports or other…

  18. 1997 hybrid electric vehicle specifications

    SciTech Connect

    Sluder, S.; Larsen, R.; Duoba, M.

    1996-10-01

    The US DOE sponsors Advanced Vehicle Technology competitions to help educate the public and advance new vehicle technologies. For several years, DOE has provided financial and technical support for the American Tour de Sol. This event showcases electric and hybrid electric vehicles in a road rally across portions of the northeastern United States. The specifications contained in this technical memorandum apply to vehicles that will be entered in the 1997 American Tour de Sol. However, the specifications were prepared to be general enough for use by other teams and individuals interested in developing hybrid electric vehicles. The purpose of the specifications is to ensure that the vehicles developed do not present a safety hazard to the teams that build and drive them or to the judges, sponsors, or public who attend the competitions. The specifications are by no means the definitive sources of information on constructing hybrid electric vehicles - as electric and hybrid vehicles technologies advance, so will the standards and practices for their construction. In some cases, the new standards and practices will make portions of these specifications obsolete.

  19. Hybrid origin of Audubon's warbler.

    PubMed

    Brelsford, Alan; Milá, Borja; Irwin, Darren E

    2011-06-01

    Several animal species have recently been shown to have hybrid origins, but no avian examples have been documented with molecular evidence. We investigate whether the Audubon's warbler (Dendroica auduboni), one of four visually distinct species in the yellow-rumped warbler complex, has originated through hybridization between two other species in this group, the myrtle warbler (D. coronata) and black-fronted warbler (D. nigrifrons). Analysis of nuclear amplified fragment length polymorphism (AFLP) and sequence markers shows that Audubon's warblers are genetically intermediate and carry a mixture of alleles otherwise found only in one or the other of their putative parental species. Audubon's warblers also carry two deeply divergent mitochondrial DNA lineages, each shared with only one putative parental form. Broad clines between Audubon's and black-fronted warblers in AFLP markers call into question the validity of these two forms as full species; nevertheless, our results suggest that the Audubon's warbler probably originated through hybridization between two long-diverged species. It is likely that more cases of avian species of hybrid origin will be revealed by surveys of variation in nuclear DNA and other traits. PMID:21435063

  20. Mandible shape in hybrid mice.

    PubMed

    Renaud, Sabrina; Alibert, Paul; Auffray, Jean-Christophe

    2009-09-01

    Hybridisation between closely related species is frequently seen as retarding evolutionary divergence and can also promote it by creating novel phenotypes due to new genetic combinations and developmental interactions. We therefore investigated how hybridisation affects the shape of the mouse mandible, a well-known feature in evo-devo studies. Parental groups corresponded to two strains of the European mouse sub-species Mus musculus domesticus and Mus musculus musculus. Parents and hybrids were bred in controlled conditions. The mandibles of F(1) hybrids are mostly intermediate between parental phenotypes as expected for a complex multigenic character. Nevertheless, a transgressive effect as well as an increased phenotypic variance characterise the hybrids. This suggests that hybridisation between the two subspecies could lead to a higher phenotypic variance due to complex interactions among the parental genomes including non-additive genetic effects. The major direction of variance is conserved, however, among hybrids and parent groups. Hybridisation may thus play a role in the production of original transgressive phenotypes occurring following pre-existing patterns of variance. PMID:19504055

  1. Magneto-Acoustic Hybrid Nanomotor.

    PubMed

    Li, Jinxing; Li, Tianlong; Xu, Tailin; Kiristi, Melek; Liu, Wenjuan; Wu, Zhiguang; Wang, Joseph

    2015-07-01

    Efficient and controlled nanoscale propulsion in harsh environments requires careful design and manufacturing of nanomachines, which can harvest and translate the propelling forces with high spatial and time resolution. Here we report a new class of artificial nanomachine, named magneto-acoustic hybrid nanomotor, which displays efficient propulsion in the presence of either magnetic or acoustic fields without adding any chemical fuel. These fuel-free hybrid nanomotors, which comprise a magnetic helical structure and a concave nanorod end, are synthesized using a template-assisted electrochemical deposition process followed by segment-selective chemical etching. Dynamic switching of the propulsion mode with reversal of the movement direction and digital speed regulation are demonstrated on a single nanovehicle. These hybrid nanomotors exhibit a diverse biomimetic collective behavior, including stable aggregation, swarm motion, and swarm vortex, triggered in response to different field inputs. Such adaptive hybrid operation and controlled collective behavior hold considerable promise for designing smart nanovehicles that autonomously reconfigure their operation mode according to their mission or in response to changes in their surrounding environment or in their own performance, thus holding considerable promise for diverse practical biomedical applications of fuel-free nanomachines. PMID:26077325

  2. Intensive production of hybrid catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Economic analysis by others shows clearly that under certain fish price-feed price combinations, intensively aerated ponds are not only an alternative, but are the profit-maximizing technology. We have raised hybrid catfish at stocking rates of 20,000/acre with aeration rates up to 10 hp/acre, produ...

  3. The threat of hybrid Phytophthoras

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The majority of invasive plant pathogens have resulted from the introduction of exotic organisms. However, another mechanism for invasiveness results from hybridization between species. This phenomenon has been documented in plants and animals, but its role in plant pathology has only recently been ...

  4. Expanding discourse repertoires with hybridity

    NASA Astrophysics Data System (ADS)

    Kelly, Gregory J.

    2012-09-01

    In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally dynamic." The hybrid discourse practices are described as involving the dynamic interplay of at least three key elements: "the lamination of multiple cultural frames, the shifting relations between people and their discourse, and the shifting power relations between and among people." Each of these elements requires a respective unit of analysis and are often mutually reinforcing. The authors present a theoretically cogent argument for the study of hybrid discourse practices and identify the potential such discourses may have for science education. This theoretical development leads to an analysis of spoken and written discourse around a set of educational events concerning the investigation of owl pellets by two fifth grade students, their classmates, and teacher. Two discourse segments are presented and analyzed by the authors in detail. The first is a discourse analysis of the dissection of the owl pellet by two students, Kyle and Max. The second analysis examines the science report of these same two students. In this article, I pose a number of questions about the study with the hope that by doing so I expand the conversation around the insightful analysis presented.

  5. Hybrid origins of cultivated potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wild and cultivated potatoes, Solanum section Petota, is taxonomically difficult, partly because of interspecific hybridization at both the diploid and polyploid levels. The taxonomy of cultivated potatoes is particularly controversial. With DNA sequence data of the GBSSI (waxy) gene we here infer r...

  6. Hybrid temperature-monitoring circuit

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.; Steffen, D. A.; Sturm, R. E.

    1979-01-01

    Hybrid circuit developed for use in hand-held vital signs monitor converts resistance of thermistor probe to 3 1/2 digit BCD (binary-coded-decimal) temperature readout. If used alone circuit can form 'stand alone' temperature monitor or can transmit temperature data via telemetry to data acquisition systems.

  7. Widely tunable hybrid semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Koh, Ping-Chiek; Plumb, Richard G. S.

    1999-04-01

    A new hybrid design tunable semiconductor laser, with a wide tuning range, a narrow linewidth, simple tuning/control algorithms, low variations in output power across its tuning range and simple fabrication, is introduced. This hybrid laser consists of a large spot reflective amplifier (LS-RA) coupled to a Lithium Niobate Acousto-Optic Filter (AOF), giving wavelength selective feedback. The LS-RA waveguide is angled by 10 degrees to the coupling facet, but is normal to the other facet, giving reflectivities of 5 X 10-5 and 3 X 10-1 respectively. This amplifier structure allows maximum coupling to the AOF without stringent alignment tolerance. THe AOF consists of a 2-stage acoustic TE/TM converter with a high TE reflectivity coating at the end. A propagating surface acoustic wave is employed to phase-match the TE and TM modes of a specific wavelength, achieving a narrow-band feedback into the LS-RA. Output power and wavelength of the hybrid laser are controlled by the LS-RA current and RF drive frequency of the AOF respectively. Simulations using a Time-Domain Model and initial experiments have shown that the hybrid laser have a wide tuning range, narrow linewidth, SMSR >= 30 dB and low power variations across its tuning range.

  8. Hybrid respiration-signal conditioner

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.; Steffen, D. A.; Sturm, R. E.

    1979-01-01

    Hybrid impedance-pneumograph and respiration-rate signal conditioner element of hand-held vital signs monitor measures changes in impedance of chest during breathing cycle and generates analog respiration signal as output along with synchronous square wave that can be monitored by breath-rate processor.

  9. Models for asymmetric hybrid brane

    NASA Astrophysics Data System (ADS)

    Bazeia, D.; Marques, M. A.; Menezes, R.

    2015-10-01

    We deal with relativistic models described by a single real scalar field, searching for topological structures that behave asymmetrically, connecting minima with a distinct profile. We use such features to build a new braneworld scenario, in which the source scalar field contributes to generate asymmetric hybrid brane.

  10. Iterative framework radiation hybrid mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Building comprehensive radiation hybrid maps for large sets of markers is a computationally expensive process, since the basic mapping problem is equivalent to the traveling salesman problem. The mapping problem is also susceptible to noise, and as a result, it is often beneficial to remove markers ...

  11. Photocarcinogenesis in Xiphophorus hybrid models.

    PubMed

    Mitchell, David L; Nairn, Rodney S

    2006-01-01

    The poeciliid fish genus Xiphophorus provides important models for investigating the etiology and genetics of sunlight-induced melanoma. Interspecific hybrids generated among platyfish and swordtails have been used as genetic tumor models, particularly for cutaneous malignant melanoma (CMM), for more than 6 decades. Oncogene and tumor suppressor gene involvement in a variety of spontaneous and carcinogen-induced tumors has been and continues to be extensively studied. Select hybrids develop melanoma spontaneously or after acute or chronic exposure to ultraviolet radiation. Many scientists believe that the etiology of CMM and particularly its initiation is different from other types of sunlight-induced skin cancers, and may involve free radical chemistry rather than the direct absorption of UVB by DNA. Xiphophorus offers a unique platform to scrutinize this question and determine the types of DNA damage that are involved, the solar wavelength ranges that are important, and the role of DNA repair genes in early tumorigenesis. The diverse photochemical and photobiological responses observed in the different Xiphophorus species and interspecies hybrids suggest that heritable traits governing DNA damage induction and repair may be involved in the susceptibility of Xiphophorus hybrids to melanomagenesis. PMID:18377212

  12. Transient combustion in hybrid rockets

    NASA Astrophysics Data System (ADS)

    Karabeyoglu, Mustafa Arif

    1998-09-01

    Hybrid rockets regained interest recently as an alternative chemical propulsion system due to their advantages over the solid and liquid systems that are currently in use. Development efforts on hybrids revealed two important problem areas: (1) low frequency instabilities and (2) slow transient response. Both of these are closely related to the transient behavior which is a poorly understood aspect of hybrid operation. This thesis is mainly involved with a theoretical study of transient combustion in hybrid rockets. We follow the methodology of identifying and modeling the subsystems of the motor such as the thermal lags in the solid, boundary layer combustion and chamber gasdynamics from a dynamic point of view. We begin with the thermal lag in the solid which yield the regression rate for any given wall heat flux variation. Interesting phenomena such as overshooting during throttling and the amplification and phase lead regions in the frequency domain are discovered. Later we develop a quasi-steady transient hybrid combustion model supported with time delays for the boundary layer processes. This is integrated with the thermal lag system to obtain the thermal combustion (TC) coupled response. The TC coupled system with positive delays generated low frequency instabilities. The scaling of the instabilities are in good agreement with actual motor test data. Finally, we formulate a gasdynamic model for the hybrid chamber which successfully resolves the filling/emptying and longitudinal acoustic behavior of the motor. The TC coupled system is later integrated to the gasdynamic model to obtain the overall response (TCG coupled system) of gaseous oxidizer motors with stiff feed systems. Low frequency instabilities were also encountered for the TCG coupled system. Apart from the transient investigations, the regression rate behavior of liquefying hybrid propellants such as solid cryogenic materials are also studied. The theory is based on the possibility of enhancement

  13. Shape Memory Composite Hybrid Hinge

    NASA Technical Reports Server (NTRS)

    Fang, Houfei; Im, Eastwood; Lin, John; Scarborough, Stephen

    2012-01-01

    There are two conventional types of hinges for in-space deployment applications. The first type is mechanically deploying hinges. A typical mechanically deploying hinge is usually composed of several tens of components. It is complicated, heavy, and bulky. More components imply higher deployment failure probability. Due to the existence of relatively moving components among a mechanically deploying hinge, it unavoidably has microdynamic problems. The second type of conventional hinge relies on strain energy for deployment. A tape-spring hinge is a typical strain energy hinge. A fundamental problem of a strain energy hinge is that its deployment dynamic is uncontrollable. Usually, its deployment is associated with a large impact, which is unacceptable for many space applications. Some damping technologies have been experimented with to reduce the impact, but they increased the risks of an unsuccessful deployment. Coalescing strain energy components with shape memory composite (SMC) components to form a hybrid hinge is the solution. SMCs are well suited for deployable structures. A SMC is created from a high-performance fiber and a shape memory polymer resin. When the resin is heated to above its glass transition temperature, the composite becomes flexible and can be folded or packed. Once cooled to below the glass transition temperature, the composite remains in the packed state. When the structure is ready to be deployed, the SMC component is reheated to above the glass transition temperature, and it returns to its as-fabricated shape. A hybrid hinge is composed of two strain energy flanges (also called tape-springs) and one SMC tube. Two folding lines are placed on the SMC tube to avoid excessive strain on the SMC during folding. Two adapters are used to connect the hybrid hinge to its adjacent structural components. While the SMC tube is heated to above its glass transition temperature, a hybrid hinge can be folded and stays at folded status after the temperature

  14. A hybrid air conditioner driven by a hybrid solar collector

    NASA Astrophysics Data System (ADS)

    Al-Alili, Ali

    The objective of this thesis is to search for an efficient way of utilizing solar energy in air conditioning applications. The current solar Air Conditioners (A/C)s suffer from low Coefficient of Performance (COP) and performance degradation in hot and humid climates. By investigating the possible ways of utilizing solar energy in air conditioning applications, the bottlenecks in these approaches were identified. That resulted in proposing a novel system whose subsystem synergy led to a COP higher than unity. The proposed system was found to maintain indoor comfort at a higher COP compared to the most common solar A/Cs, especially under very hot and humid climate conditions. The novelty of the proposed A/C is to use a concentrating photovoltaic/thermal collector, which outputs thermal and electrical energy simultaneously, to drive a hybrid A/C. The performance of the hybrid A/C, which consists of a desiccant wheel, an enthalpy wheel, and a vapor compression cycle (VCC), was investigated experimentally. This work also explored the use of a new type of desiccant material, which can be regenerated with a low temperature heat source. The experimental results showed that the hybrid A/C is more effective than the standalone VCC in maintaining the indoor conditions within the comfort zone. Using the experimental data, the COP of the hybrid A/C driven by a hybrid solar collector was found to be at least double that of the current solar A/Cs. The innovative integration of its subsystems allows each subsystem to do what it can do best. That leads to lower energy consumption which helps reduce the peak electrical loads on electric utilities and reduces the consumer operating cost since less energy is purchased during the on peak periods and less solar collector area is needed. In order for the proposed A/C to become a real alternative to conventional systems, its performance and total cost were optimized using the experimentally validated model. The results showed that for an

  15. Bounded hybrid superiority in an avian hybrid zone: effects of mate, diet, and habitat choice.

    PubMed

    Good, T P; Ellis, J C; Annett, C A; Pierotti, R

    2000-10-01

    There has been considerable debate in the study of hybrid zones as to whether hybrids may be superior to parental types within the area of contact (bounded hybrid superiority). In birds, naturally occurring hybridization is relatively common, and hybridization within this group always involves mate choice. If hybrids are superior, females choosing heterospecific mates should be expected to show higher fitness under the conditions prevalent in the hybrid zone. Hybrid superiority under these circumstances would reduce reinforcement and thereby help to maintain the hybrid zone. To examine this issue, we studied reproductive performances of hybrids and parental species of gulls (Larus occidentalis and Larus glaucescens) at two colonies within a linear hybrid zone along the west coast of the United States. This hybrid zone contains predominantly gulls of intermediate phenotype. Previous studies indicated that hybrids were superior to one or both parental types, but provided no data on possible mechanisms that underlie this hybrid superiority. Using a hybrid index designed specifically for these species, we identified to phenotype more than 300 individuals associated with nests, including both individual males and females within 73 pairs in the central portion of the hybrid zone and 74 pairs in the northern portion of the hybrid zone. There was little evidence of assortative mating, and what little there was resulted solely because of pairings within intergrades. In the central hybrid zone, females paired with hybrid males produced larger clutches and hatched and fledged more chicks compared with females paired to western gull males. This was a result of heavy predation on eggs in sand habitat, where male western gulls established territories. In contrast, many hybrid males established territories in vegetated cover that was less vulnerable to predation. In the northern part of the hybrid zone, clutch size did not differ among pair categories, however, there were

  16. Reutilization of previously hybridized slides for fluorescence in situ hybridization

    SciTech Connect

    Epstein, L.; DeVries, S.; Waldman, F.M.

    1995-12-01

    Application of fluorescence in situ hybridization (FISH) to clinical material is sometimes limited by sample size. In addition, heterogeneity among slides prepared from a single sample may lead to variation in FISH analyses. Reutilization of material for repeated FISH analyses would help to alleviate these problems. We have developed a simple procedure for repeated FISH analyses with directly conjugated probes. Previously hybridized probes are removed by incubation in denaturing solution, and slides can then be rehybridized without residual signals remaining. Several cycles of this procedure allow a full complement of chromosomal loci to be analyzed on the same population of cells. Advantages of this protocol include gaining more cytogenetic information from small samples and eliminating the problem of intratumorvariability. 5 refs., 4 figs.

  17. Hybridization of a sigma-delta-based CMOS hybrid detector

    NASA Astrophysics Data System (ADS)

    Kolb, K. E.; Stoffel, N. C.; Douglas, B.; Maloney, C. W.; Raisanen, A. D.; Ashe, B.; Figer, D. F.; Tamagawa, T.; Halpern, B.; Ignjatovic, Zeljko

    2010-07-01

    The Rochester Imaging Detector Laboratory, University of Rochester, Infotonics Technology Center, and Jet Process Corporation developed a hybrid silicon detector with an on-chip sigma-delta (ΣΔ) ADC. This paper describes the process and reports the results of developing a fabrication process to robustly produce high-quality bump bonds to hybridize a back-illuminated detector with its ΣΔ ADC. The design utilizes aluminum pads on both the readout circuit and the photodiode array with interconnecting indium bumps between them. The development of the bump bonding process is discussed, including specific material choices, interim process structures, and final functionality. Results include measurements of bond integrity, cross-wafer uniformity of indium bumps, and effects of process parameters on the final product. Future plans for improving the bump bonding process are summarized.

  18. Towards stable silicon nanoarray hybrid solar cells

    PubMed Central

    He, W. W.; Wu, K. J.; Wang, K.; Shi, T. F.; Wu, L.; Li, S. X.; Teng, D. Y.; Ye, C. H.

    2014-01-01

    Silicon nanoarray hybrid solar cells benefit from the ease of fabrication and the cost-effectiveness of the hybrid structure, and represent a new research focus towards the utilization of solar energy. However, hybrid solar cells composed of both inorganic and organic components suffer from the notorious stability issue, which has to be tackled before the hybrid solar cells could become a viable alternative for harvesting solar energy. Here we show that Si nanoarray/PEDOT:PSS hybrid solar cells with improved stability can be fabricated via eliminating the water inclusion in the initial formation of the heterojunction between Si nanoarray and PEDOT:PSS. The Si nanoarray hybrid solar cells are stable against rapid degradation in the atmosphere environment for several months without encapsulation. This finding paves the way towards the real-world applications of Si nanoarray hybrid solar cells. PMID:24430057

  19. Hybrid methods for cybersecurity analysis :

    SciTech Connect

    Davis, Warren Leon,; Dunlavy, Daniel M.

    2014-01-01

    Early 2010 saw a signi cant change in adversarial techniques aimed at network intrusion: a shift from malware delivered via email attachments toward the use of hidden, embedded hyperlinks to initiate sequences of downloads and interactions with web sites and network servers containing malicious software. Enterprise security groups were well poised and experienced in defending the former attacks, but the new types of attacks were larger in number, more challenging to detect, dynamic in nature, and required the development of new technologies and analytic capabilities. The Hybrid LDRD project was aimed at delivering new capabilities in large-scale data modeling and analysis to enterprise security operators and analysts and understanding the challenges of detection and prevention of emerging cybersecurity threats. Leveraging previous LDRD research e orts and capabilities in large-scale relational data analysis, large-scale discrete data analysis and visualization, and streaming data analysis, new modeling and analysis capabilities were quickly brought to bear on the problems in email phishing and spear phishing attacks in the Sandia enterprise security operational groups at the onset of the Hybrid project. As part of this project, a software development and deployment framework was created within the security analyst work ow tool sets to facilitate the delivery and testing of new capabilities as they became available, and machine learning algorithms were developed to address the challenge of dynamic threats. Furthermore, researchers from the Hybrid project were embedded in the security analyst groups for almost a full year, engaged in daily operational activities and routines, creating an atmosphere of trust and collaboration between the researchers and security personnel. The Hybrid project has altered the way that research ideas can be incorporated into the production environments of Sandias enterprise security groups, reducing time to deployment from months and

  20. Atom-Light Hybrid Interferometer.

    PubMed

    Chen, Bing; Qiu, Cheng; Chen, Shuying; Guo, Jinxian; Chen, L Q; Ou, Z Y; Zhang, Weiping

    2015-07-24

    A new type of hybrid atom-light interferometer is demonstrated with atomic Raman amplification processes replacing the beam splitting elements in a traditional interferometer. This nonconventional interferometer involves correlated optical and atomic waves in the two arms. The correlation between atoms and light developed with the Raman process makes this interferometer different from conventional interferometers with linear beam splitters. It is observed that the high-contrast interference fringes are sensitive to the optical phase via a path change as well as the atomic phase via a magnetic field change. This new atom-light correlated hybrid interferometer is a sensitive probe of the atomic internal state and should find wide applications in precision measurement and quantum control with atoms and photons. PMID:26252684

  1. Hybrid optomechanics for Quantum Technologies

    NASA Astrophysics Data System (ADS)

    Rogers, B.; Lo Gullo, N.; De Chiara, G.; Palma, G. M.; Paternostro, M.

    2014-06-01

    We review the physics of hybrid optomechanical systems consisting of a mechanical oscillator interacting with both a radiation mode and an additional matterlike system. We concentrate on the cases embodied by either a single or a multi-atom system (a Bose-Einstein condensate, in particular) and discuss a wide range of physical effects, from passive mechanical cooling to the set-up of multipartite entanglement, from optomechanical nonlocality to the achievement of non-classical states of a single mechanical mode. The reviewed material showcases the viability of hybridised cavity optomechanical systems as basic building blocks for quantum communication networks and quantum state-engineering devices, possibly empowered by the use of quantum and optimal control techniques. The results that we discuss are instrumental to the promotion of hybrid optomechanical devices as promising experimental platforms for the study of nonclassicality at the genuine mesoscopic level.

  2. Hybrid chirped pulse amplification system

    DOEpatents

    Barty, Christopher P.; Jovanovic, Igor

    2005-03-29

    A hybrid chirped pulse amplification system wherein a short-pulse oscillator generates an oscillator pulse. The oscillator pulse is stretched to produce a stretched oscillator seed pulse. A pump laser generates a pump laser pulse. The stretched oscillator seed pulse and the pump laser pulse are directed into an optical parametric amplifier producing an optical parametric amplifier output amplified signal pulse and an optical parametric amplifier output unconverted pump pulse. The optical parametric amplifier output amplified signal pulse and the optical parametric amplifier output laser pulse are directed into a laser amplifier producing a laser amplifier output pulse. The laser amplifier output pulse is compressed to produce a recompressed hybrid chirped pulse amplification pulse.

  3. Planar slot coupled microwave hybrid

    DOEpatents

    Petter, Jeffrey K.

    1991-01-01

    A symmetrical 180.degree. microwave hybrid is constructed by opening a slot line in a ground plane below a conducting strip disposed on a dielectric substrate, creating a slot coupled conductor. Difference signals propagating on the slot coupled conductor are isolated on the slot line leaving sum signals to propagate on the microstrip. The difference signal is coupled from the slot line onto a second microstrip line for transmission to a desired location. The microstrip branches in a symmetrical fashion to provide the input/output ports of the 180.degree. hybrid. The symmetry of the device provides for balance and isolation between sum and difference signals, and provides an advantageous balance between the power handling capabilities and the bandwidth of the device.

  4. Nanorice: a new hybrid nanostructure

    NASA Astrophysics Data System (ADS)

    Nordlander, P.; Brandl, D.; Le, F.; Wang, H.; Halas, N. J.

    2006-03-01

    The plasmon hybridization method [1] is applied to nanorice, a new metallic nanostructure which combines the properties of two popular tunable plasmonic nanoparticle geometries: nanorods and nanoshells. The particle consists of a prolate spheroidal dielectric core and a thin metallic shell, bearing a remarkable resemblance to a rice grain. The nanorice particle shows far greater geometric tunability of the optical resonance, larger local field intensity enhancements and far greater sensitivity as a surface plasmon resonance (SPR) nanosensor than any previously reported dielectric-metal nanostructure. The tunability of the nanorice particle arises from the interaction of primitive plasmons associated with the inner and outer surfaces of the shell. The results from plasmon hybridization are compared to FDTD simulations. [1] E. Prodan and P. Nordlander, J. Chem. Phys. 120(2004)5444-5454

  5. Protein-inorganic hybrid nanoflowers

    NASA Astrophysics Data System (ADS)

    Ge, Jun; Lei, Jiandu; Zare, Richard N.

    2012-07-01

    Flower-shaped inorganic nanocrystals have been used for applications in catalysis and analytical science, but so far there have been no reports of `nanoflowers' made of organic components. Here, we report a method for creating hybrid organic-inorganic nanoflowers using copper (II) ions as the inorganic component and various proteins as the organic component. The protein molecules form complexes with the copper ions, and these complexes become nucleation sites for primary crystals of copper phosphate. Interaction between the protein and copper ions then leads to the growth of micrometre-sized particles that have nanoscale features and that are shaped like flower petals. When an enzyme is used as the protein component of the hybrid nanoflower, it exhibits enhanced enzymatic activity and stability compared with the free enzyme. This is attributed to the high surface area and confinement of the enzymes in the nanoflowers.

  6. Hybrid sugarbeets - fuel from fodder

    SciTech Connect

    Yarris, L.

    1980-05-01

    Plant geneticists at Utah University are exploring the possibility of developing a hybrid sugarbeet especially bred for use in making alcohol fuel. They are aiming at increasing sugar quantity in the beet without having to worry about the quality factors that affect sugar crystallization. A cross between European fodder beets and U.S. sugarbeets which would be resistant to curly top virus disease is envisaged.

  7. Active and Passive Hybrid Sensor

    NASA Technical Reports Server (NTRS)

    Carswell, James R.

    2010-01-01

    A hybrid ocean wind sensor (HOWS) can map ocean vector wind in low to hurricane-level winds, and non-precipitating and precipitating conditions. It can acquire active and passive measurements through a single aperture at two wavelengths, two polarizations, and multiple incidence angles. Its low profile, compact geometry, and low power consumption permits installation on air craft platforms, including high-altitude unmanned aerial vehicles (UAVs).

  8. Hybrid optical acoustic seafloor mapping

    NASA Astrophysics Data System (ADS)

    Inglis, Gabrielle

    The oceanographic research and industrial communities have a persistent demand for detailed three dimensional sea floor maps which convey both shape and texture. Such data products are used for archeology, geology, ship inspection, biology, and habitat classification. There are a variety of sensing modalities and processing techniques available to produce these maps and each have their own potential benefits and related challenges. Multibeam sonar and stereo vision are such two sensors with complementary strengths making them ideally suited for data fusion. Data fusion approaches however, have seen only limited application to underwater mapping and there are no established methods for creating hybrid, 3D reconstructions from two underwater sensing modalities. This thesis develops a processing pipeline to synthesize hybrid maps from multi-modal survey data. It is helpful to think of this processing pipeline as having two distinct phases: Navigation Refinement and Map Construction. This thesis extends existing work in underwater navigation refinement by incorporating methods which increase measurement consistency between both multibeam and camera. The result is a self consistent 3D point cloud comprised of camera and multibeam measurements. In map construction phase, a subset of the multi-modal point cloud retaining the best characteristics of each sensor is selected to be part of the final map. To quantify the desired traits of a map several characteristics of a useful map are distilled into specific criteria. The different ways that hybrid maps can address these criteria provides justification for producing them as an alternative to current methodologies. The processing pipeline implements multi-modal data fusion and outlier rejection with emphasis on different aspects of map fidelity. The resulting point cloud is evaluated in terms of how well it addresses the map criteria. The final hybrid maps retain the strengths of both sensors and show significant improvement

  9. Hybrid Power Management Program Continued

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2002-01-01

    Hybrid Power Management (HPM) is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors and photovoltaics. HPM has extremely wide potential with applications including power-generation, transportation, biotechnology, and space power systems. It may significantly alleviate global energy concerns, improve the environment, and stimulate the economy.

  10. Complex Hybrid Inflation and Baryogenesis

    SciTech Connect

    Delepine, David; Martinez, Carlos; Urena-Lopez, L. Arturo

    2007-04-20

    We propose a hybrid inflation model with a complex waterfall field which contains an interaction term that breaks the U(1) global symmetry associated with the waterfall field charge. We show that the asymmetric evolution of the real and imaginary parts of the complex field during the phase transition at the end of inflation translates into a charge asymmetry. The latter strongly depends on the vacuum expectation value of the waterfall field, which is well constrained by diverse cosmological observations.

  11. Electroactive functional hybrid layered nanocomposites

    SciTech Connect

    Destri, Giovanni Li; Torrisi, Vanna; Marletta, Giovanni

    2012-07-11

    Two methodologies to build new nanostructured hybrid layered nanocomposites are presented. The first one involves the preparation of hybrid metal/polymer nanolayers (NLs) by combining two monolayer preparation techniques: Horizontal Precipitation Langmuir Blodgett method (HP-ML), for copolymer monolayers and sputter deposition technique, for Au NLs deposition. The second methodology is aimed to prepare regular arrays of nanopores, with diameter ranging between 40-100 nm, in ultra-thin films of electroactive polymers, to obtain embedded regular arrays of nanopores filled by a further electroactive organic component. The produced hybrid MLs have been characterized by means of X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and Grazing Incidence X-ray Diffraction (GI-XRD). In the first case, current-voltage (I-V) measurements demonstrate that the multilayers exhibit a bipolar conduction behaviour (electrons and holes carriers), with a peculiar transition in the nature of the majority carriers (from holes to electrons) above a threshold number of bilayers. In the second case, it is found that the degree of pore filling, as well as the polymer crystallinity can be easily modulated, prompting the tuning of the photoresponse of the nanocomposites.

  12. Electroactive functional hybrid layered nanocomposites

    NASA Astrophysics Data System (ADS)

    Destri, Giovanni Li; Torrisi, Vanna; Marletta, Giovanni

    2012-07-01

    Two methodologies to build new nanostructured hybrid layered nanocomposites are presented. The first one involves the preparation of hybrid metal/polymer nanolayers (NLs) by combining two monolayer preparation techniques: Horizontal Precipitation Langmuir Blodgett method (HP-ML), for copolymer monolayers and sputter deposition technique, for Au NLs deposition. The second methodology is aimed to prepare regular arrays of nanopores, with diameter ranging between 40-100 nm, in ultra-thin films of electroactive polymers, to obtain embedded regular arrays of nanopores filled by a further electroactive organic component. The produced hybrid MLs have been characterized by means of X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and Grazing Incidence X-ray Diffraction (GI-XRD). In the first case, current-voltage (I-V) measurements demonstrate that the multilayers exhibit a bipolar conduction behaviour (electrons and holes carriers), with a peculiar transition in the nature of the majority carriers (from holes to electrons) above a threshold number of bilayers. In the second case, it is found that the degree of pore filling, as well as the polymer crystallinity can be easily modulated, prompting the tuning of the photoresponse of the nanocomposites.

  13. Standard-smooth hybrid inflation

    SciTech Connect

    Lazarides, George; Vamvasakis, Achilleas

    2007-12-15

    We consider the extended supersymmetric Pati-Salam model which, for {mu}>0 and universal boundary conditions, succeeds to yield experimentally acceptable b-quark masses by moderately violating Yukawa unification. It is known that this model can lead to new shifted or new smooth hybrid inflation. We show that a successful two-stage inflationary scenario can be realized within this model based only on renormalizable superpotential interactions. The cosmological scales exit the horizon during the first stage of inflation, which is of the standard hybrid type and takes place along the trivial flat direction with the inflaton driven by radiative corrections. Spectral indices compatible with the recent data can be achieved in global supersymmetry or minimal supergravity by restricting the number of e-foldings of our present horizon during the first inflationary stage. The additional e-foldings needed for solving the horizon and flatness problems are naturally provided by a second stage of inflation, which occurs mainly along the built-in new smooth hybrid inflationary path appearing right after the destabilization of the trivial flat direction at its critical point. Monopoles are formed at the end of the first stage of inflation and are, subsequently, diluted by the second stage of inflation to become utterly negligible in the present universe for almost all (for all) the allowed values of the parameters in the case of global supersymmetry (minimal supergravity)

  14. Electric and hybrid vehicles program

    NASA Astrophysics Data System (ADS)

    1990-04-01

    This thirteenth annual report on the implementation of the Electric and Hybrid Vehicle Research, Development and Demonstration Act of 1976 (Public Law 94-413), referred to as the Act, complies with the reporting requirements established in section 14 of the Act. In addition to informing Congress of the progress and plans of the Department of Energy's Electric and Hybrid Vehicles Program, this report is intended to serve as a communication link between the Department and all of the public and private interests involved in making the program a success. During FY 1989, significant progress was made in this program. There has been continuing interest shown by both the automobile manufacturers and supply sectors of our economy in electric and hybrid vehicles. The three major domestic automobile manufacturers all are devoting some effort towards electric vehicles. Their participation includes cost-shared contracts with Department of Energy and the Electric Power Research Institute as well as independently funded activities. Research and development efforts in batteries and propulsion components continue to achieve significant progress in providing industry with technology that will result in vehicles that will be more economically competitive.

  15. Additive manufacturing of hybrid circuits

    DOE PAGESBeta

    Bell, Nelson S.; Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David M.; Hirschfeld, Deidre; Hall, Aaron Christopher

    2016-03-26

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects.more » Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. As a result, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.« less

  16. Gravity localization on hybrid branes

    NASA Astrophysics Data System (ADS)

    Veras, D. F. S.; Cruz, W. T.; Maluf, R. V.; Almeida, C. A. S.

    2016-03-01

    This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behavior is manifested when the extra dimension is outside the compact domain, where the energy density is non-trivial, instead of asymptotically as in the usual thick brane models. The zero mode is trapped in the brane, as required. The massive modes, although not localized in the brane, have important phenomenological implications such as corrections to the Newton's law. We study such corrections in the usual thick domain wall and in the hybrid brane scenarios. By means of suitable numerical methods, we attain the mass spectrum for the graviton and the corresponding wavefunctions. The spectra possess the usual linearly increasing behavior from the Kaluza-Klein theories. Further, we show that the 4D gravitational force is slightly increased at short distances. The first eigenstate contributes highly for the correction to the Newton's law. The subsequent normalized solutions have diminishing contributions. Moreover, we find out that the phenomenology of the hybrid brane is not different from the usual thick domain wall. The use of numerical techniques for solving the equations of the massive modes is useful for matching possible phenomenological measurements in the gravitational law as a probe to warped extra dimensions.

  17. Quantifying hybridization in realistic time.

    PubMed

    Collins, Joshua; Linz, Simone; Semple, Charles

    2011-10-01

    Recently, numerous practical and theoretical studies in evolutionary biology aim at calculating the extent to which reticulation-for example, horizontal gene transfer, hybridization, or recombination-has influenced the evolution for a set of present-day species. It has been shown that inferring the minimum number of hybridization events that is needed to simultaneously explain the evolutionary history for a set of trees is an NP-hard and also fixed-parameter tractable problem. In this article, we give a new fixed-parameter algorithm for computing the minimum number of hybridization events for when two rooted binary phylogenetic trees are given. This newly developed algorithm is based on interleaving-a technique using repeated kernelization steps that are applied throughout the exhaustive search part of a fixed-parameter algorithm. To show that our algorithm runs efficiently to be applicable to a wide range of practical problem instances, we apply it to a grass data set and highlight the significant improvements in terms of running times in comparison to an algorithm that has previously been implemented. PMID:21210735

  18. Flight Testing of Hybrid Powered Vehicles

    NASA Technical Reports Server (NTRS)

    Story, George; Arves, Joe

    2006-01-01

    Hybrid Rocket powered vehicles have had a limited number of flights. Most recently in 2004, Scaled Composites had a successful orbital trajectory that put a private vehicle twice to over 62 miles high, the edge of space to win the X-Prize. This endeavor man rates a hybrid system. Hybrids have also been used in a number of one time launch attempts - SET-1, HYSR, HPDP. Hybrids have also been developed for use and flown in target drones. This chapter discusses various flight-test programs that have been conducted, hybrid vehicles that are in development, other hybrid vehicles that have been proposed and some strap-on applications have also been examined.

  19. Synergistic hybrid organic-inorganic aerogels.

    PubMed

    Wang, Xiao; Jana, Sadhan C

    2013-07-10

    A class of inorganic-organic hybrid mesoporous aerogel structure was synthesized by growing gel in a gel. In Type 1, silica gels were grown inside the macropores of thermoreversible syndiotactic polystyrene (sPS) gel, while Type 2 hybrid aerogels were obtained by thermoreversible gelation of sPS chains in the mesopores of preformed silica gel. The hybrid gels were converted into aerogels by exchanging the solvent with liquid carbon dioxide followed by supercritical drying. The hybrid aerogels presented cocontinuous networks of pearl-necklace silica particles and crystalline strands of sPS and exhibited the "petal effect" due to the presence of superhydrophobic sPS and hygroscopic silica. The compressive modulus and compressive strain show large enhancements over sPS and silica aerogels indicating synergy, although Type 1 hybrid aerogels were found to be more robust. The hybrid aerogels showed fast absorption and high absorption capacity for a representative hydrocarbon liquid. PMID:23773123

  20. Model-Based Prognostics of Hybrid Systems

    NASA Technical Reports Server (NTRS)

    Daigle, Matthew; Roychoudhury, Indranil; Bregon, Anibal

    2015-01-01

    Model-based prognostics has become a popular approach to solving the prognostics problem. However, almost all work has focused on prognostics of systems with continuous dynamics. In this paper, we extend the model-based prognostics framework to hybrid systems models that combine both continuous and discrete dynamics. In general, most systems are hybrid in nature, including those that combine physical processes with software. We generalize the model-based prognostics formulation to hybrid systems, and describe the challenges involved. We present a general approach for modeling hybrid systems, and overview methods for solving estimation and prediction in hybrid systems. As a case study, we consider the problem of conflict (i.e., loss of separation) prediction in the National Airspace System, in which the aircraft models are hybrid dynamical systems.

  1. Hybrid and Plug-in Electric Vehicles

    SciTech Connect

    2014-05-20

    Hybrid and plug-in electric vehicles use electricity either as their primary fuel or to improve the efficiency of conventional vehicle designs. This new generation of vehicles, often called electric drive vehicles, can be divided into three categories: hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles(PHEVs), and all-electric vehicles (EVs). Together, they have great potential to reduce U.S. petroleum use.

  2. Vertebrate Cells Express Protozoan Antigen after Hybridization

    NASA Astrophysics Data System (ADS)

    Crane, Mark St. J.; Dvorak, James A.

    1980-04-01

    Epimastigotes, the invertebrate host stage of Trypanosoma cruzi, the protozoan parasite causing Chagas' disease in man, were fused with vertebrate cells by using polyethylene glycol. Hybrid cells were selected on the basis of T. cruzi DNA complementation of biochemical deficiencies in the vertebrate cells. Some clones of the hybrid cells expressed T. cruzi-specific antigen. It might be possible to use selected antigens obtained from the hybrids as vaccines for immunodiagnosis or for elucidation of the pathogenesis of Chagas' disease.

  3. Hybrid evolutionary programming for heavily constrained problems.

    PubMed

    Myung, H; Kim, J H

    1996-01-01

    A hybrid of evolutionary programming (EP) and a deterministic optimization procedure is applied to a series of non-linear and quadratic optimization problems. The hybrid scheme is compared with other existing schemes such as EP alone, two-phase (TP) optimization, and EP with a non-stationary penalty function (NS-EP). The results indicate that the hybrid method can outperform the other methods when addressing heavily constrained optimization problems in terms of computational efficiency and solution accuracy. PMID:8833746

  4. Parallel Hybrid Vehicle Optimal Storage System

    NASA Technical Reports Server (NTRS)

    Bloomfield, Aaron P.

    2009-01-01

    A paper reports the results of a Hybrid Diesel Vehicle Project focused on a parallel hybrid configuration suitable for diesel-powered, medium-sized, commercial vehicles commonly used for parcel delivery and shuttle buses, as the missions of these types of vehicles require frequent stops. During these stops, electric hybridization can effectively recover the vehicle's kinetic energy during the deceleration, store it onboard, and then use that energy to assist in the subsequent acceleration.

  5. A genomic perspective on hybridization and speciation

    PubMed Central

    Payseur, Bret A.; Rieseberg, Loren H.

    2016-01-01

    Hybridization among diverging lineages is common in nature. Genomic data provide a special opportunity to characterize the history of hybridization and the genetic basis of speciation. We review existing methods and empirical studies to identify recent advances in the genomics of hybridization, as well as issues that need to be addressed. Notable progress has been made in the development of methods for detecting hybridization and inferring individual ancestries. However, few approaches reconstruct the magnitude and timing of gene flow, estimate the fitness of hybrids or incorporate knowledge of recombination rate. Empirical studies indicate that the genomic consequences of hybridization are complex, including a highly heterogeneous landscape of differentiation. Inferred characteristics of hybridization differ substantially among species groups. Loci showing unusual patterns – which may contribute to reproductive barriers – are usually scattered throughout the genome, with potential enrichment in sex chromosomes and regions of reduced recombination. We caution against the growing trend of interpreting genomic variation in summary statistics across genomes as evidence of differential gene flow. We argue that converting genomic patterns into useful inferences about hybridization will ultimately require models and methods that directly incorporate key ingredients of speciation, including the dynamic nature of gene flow, selection acting in hybrid populations and recombination rate variation. PMID:26836441

  6. On Hybrid and mixed finite element methods

    NASA Technical Reports Server (NTRS)

    Pian, T. H. H.

    1981-01-01

    Three versions of the assumed stress hybrid model in finite element methods and the corresponding variational principles for the formulation are presented. Examples of rank deficiency for stiffness matrices by the hybrid stress model are given and their corresponding kinematic deformation modes are identified. A discussion of the derivation of general semi-Loof elements for plates and shells by the hybrid stress method is given. It is shown that the equilibrium model by Fraeijs de Veubeke can be derived by the approach of the hybrid stress model as a special case of semi-Loof elements.

  7. Hybrid Multicomponent Hydrogels for Tissue Engineering

    PubMed Central

    Jia, Xinqiao; Kiick, Kristi L.

    2009-01-01

    Artificial ECMs that not only closely mimic the hybrid nature of the natural ECM but also provide tunable material properties and enhanced biological functions are attractive candidates for tissue engineering applications. This review summarizes recent advances in developing multicomponent hybrid hydrogels by integrating modular and heterogeneous building blocks into well-defined, multifunctional hydrogel composites. The individual building blocks can be chemically, morphologically, and functionally diverse, and the hybridization can occur at molecular level or microscopic scale. The modular nature of the designs, combined with the potential synergistic effects of the hybrid systems, has resulted in novel hydrogel matrices with robust structure and defined functions. PMID:19107720

  8. Organic/inorganic hybrid coatings for anticorrosion

    NASA Astrophysics Data System (ADS)

    He, Zhouying

    Compared to organic coatings, organic-inorganic hybrid coatings can potentially improve the anticorrosion performance. The organic phase provides the excellent mechaincal and barrier properties while the inorganic phase acts as an adhesion promoter and corrosion inhibitor. Despite that many studies on alkoxylsilane-based hybrid coatings have been developed and studied, their weatherability and anticorrosion performance has been rarely evaluated. On the other hand, organic-inorganic hybrid coatings based on mixed sol-gel precursors have received much less attention compared to alkoxylsilane-based hybrid coatings. In the first part, polyurethane hybrid coatings with a unique hybrid crosslinked structure as an improved unicoat were successfully prepared. The effect of polyesters on physical properties of the hybrid coatings was studied. Polyurethane coatings derived from cycloaliphatic polyester show comparable properties than those derived from the commercially viable aromatic polyester. Introducing the polysiloxane part into the polyurethane coatings enhanced the crosslinking density, Tg, mechanical properties, and general coating properties. The increased adhesion between the hybrid coating and the substrate make the hybrid coating a good candidate for anticorrosion application, which is shown by electrochemical impedance spectroscopy (EIS). The degradation mechanism of the polyurethane/polysiloxane hybrid coatings under various weathering conditions was shown to be the scission of the urethane and ester groups in the organic phase along with reorganizing and rearranging of the inorganic phase. The anticorrosion performance of the cycloaliphatic hybrid was much better than that of aromatic based hybrid under outdoor weathering based on visual observation and EIS analysis. Acid undercutting is an issue for TEOS based hybrid coating. In the second part, design of experiments (DOEs) was used to statistically investigate on the effect of sol-gel precursors. The

  9. Hybrid slab-microchannel gel electrophoresis system

    DOEpatents

    Balch, Joseph W.; Carrano, Anthony V.; Davidson, James C.; Koo, Jackson C.

    1998-01-01

    A hybrid slab-microchannel gel electrophoresis system. The hybrid system permits the fabrication of isolated microchannels for biomolecule separations without imposing the constraint of a totally sealed system. The hybrid system is reusable and ultimately much simpler and less costly to manufacture than a closed channel plate system. The hybrid system incorporates a microslab portion of the separation medium above the microchannels, thus at least substantially reducing the possibility of non-uniform field distribution and breakdown due to uncontrollable leakage. A microslab of the sieving matrix is built into the system by using plastic spacer materials and is used to uniformly couple the top plate with the bottom microchannel plate.

  10. Hybrid model for solidification and convection

    NASA Technical Reports Server (NTRS)

    Oldenburg, Curtis M.; Spera, Frank J.

    1992-01-01

    A hybrid model for continuum phase-change problems is presented. The hybrid model accounts for flow in regions of concentrated mush, dilute mush, and single-phase liquid. Scale analysis shows that, in dilute mush, the Blake-Kozeny-Carman relation may lead to inaccuracy in the continuum formulation for certain values of the Rayleigh and Darcy numbers. The hybrid model uses arctangent switching functions to switch on the Darcy flow and variable viscosity terms depending on the local value of the fraction solid. Two-dimensional example calculations suggest that the hybrid model more accurately accounts for transport in the dilute mush region.

  11. Hybrid dampers for active vibration control

    SciTech Connect

    Gordaninejad, F.; Ray, A.

    1994-12-31

    In the present investigation feasibility of using hybrid electrorheological (ER) fluid dampers for active vibration control is examined. Small-scale, three-electrode hybrid dampers were designed and built such that they have two separate compartments to contain a viscous oil and an ER fluid. The results were compared to those obtained using a three-electrode ER fluid damper. It was shown that the use of hybrid ER fluid damper can enhance the damping. It was also found that the bang-bang and linear proportional control algorithms have similar effects on the amplitude-time response obtained from hybrid and ER fluid dampers.

  12. Interploidy hybridization in sympatric zones: the formation of Epidendrum fulgens × E. puniceoluteum hybrids (Epidendroideae, Orchidaceae)

    PubMed Central

    Moraes, Ana P; Chinaglia, Mariana; Palma-Silva, Clarisse; Pinheiro, Fábio

    2013-01-01

    Interspecific hybridization is a primary cause of extensive morphological and chromosomal variation and plays an important role in plant species diversification. However, the role of interploidal hybridization in the formation of hybrid swarms is less clear. Epidendrum encompasses wide variation in chromosome number and lacks strong premating barriers, making the genus a good model for clarifying the role of chromosomes in postzygotic barriers in interploidal hybrids. In this sense, hybrids from the interploidal sympatric zone between E. fulgens (2n = 2x = 24) and E. puniceoluteum (2n = 4x = 56) were analyzed using cytogenetic techniques to elucidate the formation and establishment of interploidal hybrids. Hybrids were not a uniform group: two chromosome numbers were observed, with the variation being a consequence of severe hybrid meiotic abnormalities and backcrossing with E. puniceoluteum. The hybrids were triploids (2n = 3x = 38 and 40) and despite the occurrence of enormous meiotic problems associated with triploidy, the hybrids were able to backcross, producing successful hybrid individuals with broad ecological distributions. In spite of the nonpolyploidization of the hybrid, its formation is a long-term evolutionary process rather than a product of a recent disturbance, and considering other sympatric zones in Epidendrum, these events could be recurrent. PMID:24198942

  13. Hybrid laminar flow control study

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Hybrid laminar flow control (HLFC) in which leading edge suction is used in conjunction with wing pressure distribution tailoring to postpone boundary layer transition and reduce friction drag was examined. Airfoil design characteristics required for laminar flow control (LFC) were determined. The aerodynamic design of the HLFC wing for a 178 passenger commercial turbofan transport was developed, and a drag was estimated. Systems changes required to install HLFC were defined, and weights and fuel economy were estimated. The potential for 9% fuel reduction for a 3926-km (2120-nmi) mission is identified.

  14. Hybrid grapheme plasmonic waveguide modulators

    NASA Astrophysics Data System (ADS)

    Ansell, D.; Thackray, B. D.; Aznakayeva, D. E.; Thomas, P.; Auton, G. H.; Marshall, O. P.; Rodriguez, F. J.; Radko, I. P.; Han, Z.; Bozhevolnyi, S. I.; Grigorenko, A. N.

    2016-03-01

    The unique optical and electronic properties of graphene allow one to realize active optical devices. While several types of graphene-based photonic modulators have already been demonstrated, the potential of combining the versatility of graphene with sub-wavelength field confinement of plasmonic/metallic structures is not fully realized. Here we report fabrication and study of hybrid graphene-plasmonic modulators. We consider several types of modulators and identify the most promising one for light modulation at telecom and near-infrared. Our proof-of-concept results pave the way towards on-chip realization of efficient graphene-based active plasmonic waveguide devices for optical communications.

  15. Hybrid spread spectrum radio system

    DOEpatents

    Smith, Stephen F.; Dress, William B.

    2010-02-02

    Systems and methods are described for hybrid spread spectrum radio systems. A method includes modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control an amplification circuit that provides a gain to the signal. Another method includes: modulating a signal by utilizing a subset of bits from a pseudo-random code generator to control a fast hopping frequency synthesizer; and fast frequency hopping the signal with the fast hopping frequency synthesizer, wherein multiple frequency hops occur within a single data-bit time.

  16. Electric and Hybrid Vehicles Program

    NASA Astrophysics Data System (ADS)

    1994-08-01

    This program, in cooperation with industry, is conducting research, development, testing, and evaluation activities to develop the technologies that would lead to production and introduction of low-and zero-emission electric and hybrid vehicles into the Nation's transportation fleet. This annual report describes program activities in the areas of advanced battery, fuel cell, and propulsion systems development. Testing and evaluation of new technology in fleet site operations and laboratories are also provided. Also presented is status on incentives (CAFE, 1992 Energy Policy Act) and use of foreign components, and a listing of publications by DOE, national laboratories, and contractors.

  17. Serendipitous discovery of the faint solar twin Inti 1

    NASA Astrophysics Data System (ADS)

    Galarza, Jhon Yana; Meléndez, Jorge; Cohen, Judith G.

    2016-04-01

    Context. Solar twins are increasingly the subject of many studies owing to their wide range of applications from testing stellar evolution models to the calibration of fundamental observables; these stars are also of interest because high precision abundances could be achieved that are key to investigating the chemical anomalies imprinted by planet formation. Furthermore, the advent of photometric surveys with large telescopes motivates the identification of faint solar twins in order to set the zero point of fundamental calibrations. Aims: We intend to perform a detailed line-by-line differential analysis to verify whether 2MASS J23263267-0239363 (designated here as Inti 1) is indeed a solar twin. Methods: We determine the atmospheric parameters and differential abundances using high-resolution (R ≈ 50 000), high signal-to-noise (S/N ≈ 110-240 per pixel) Keck/HIRES spectra for our solar twin candidate, the previously known solar twin HD 45184, and the Sun (using reflected light from the asteroid Vesta). Results: For the bright solar twin HD 45184, we found Teff = 5864 ± 9 K, log g = 4.45 ± 0.03 dex, vt = 1.11 ± 0.02 km s-1, and [Fe/H] = 0.04 ± 0.01 dex, which are in good agreement with previous works. Our abundances are in excellent agreement with a recent high-precision work, with an element-to-element scatter of only 0.01 dex. The star Inti 1 has atmospheric parameters Teff = 5837 ± 11 K, log g = 4.42 ± 0.03 dex, vt = 1.04 ± 0.02 km s-1, and [Fe/H] = 0.07 ± 0.01 dex that are higher than solar. The age and mass of the solar twin HD 45184 (3 Gyr and 1.05 M⊙) and the faint solar twin Inti 1 (4 Gyr and 1.04 M⊙) were estimated using isochrones. The differential analysis shows that HD 45184 presents an abundance pattern that is similar to typical nearby solar twins; this means this star has an enhanced refractory relative to volatile elements, while Inti 1 has an abundance pattern closer to solar, albeit somewhat enhanced in refractories. The abundance pattern of HD 45184 and Inti 1 could be reproduced by adding ≈3.5 M⊕ and ≈1.5 M⊕ of Earth-like material to the convective zone of the Sun. Conclusions: The star Inti 1 is a faint solar twin, therefore, it could be used to calibrate the zero points of different photometric systems. The distant solar twin Inti 1 has an abundance pattern similar to the Sun with only a minor enhancement in the refractory elements. It would be important to analyze other distant solar twins to verify whether they share the Sun's abundance pattern or if they are enhanced in refractories, as is the case in the majority of nearby solar twins. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.

  18. The serendipitous origin of chordate secretin peptide family members

    PubMed Central

    2010-01-01

    Background The secretin family is a pleotropic group of brain-gut peptides with affinity for class 2 G-protein coupled receptors (secretin family GPCRs) proposed to have emerged early in the metazoan radiation via gene or genome duplications. In human, 10 members exist and sequence and functional homologues and ligand-receptor pairs have been characterised in representatives of most vertebrate classes. Secretin-like family GPCR homologues have also been isolated in non-vertebrate genomes however their corresponding ligands have not been convincingly identified and their evolution remains enigmatic. Results In silico sequence comparisons failed to retrieve a non-vertebrate (porifera, cnidaria, protostome and early deuterostome) secretin family homologue. In contrast, secretin family members were identified in lamprey, several teleosts and tetrapods and comparative studies revealed that sequence and structure is in general maintained. Sequence comparisons and phylogenetic analysis revealed that PACAP, VIP and GCG are the most highly conserved members and two major peptide subfamilies exist; i) PACAP-like which includes PACAP, PRP, VIP, PH, GHRH, SCT and ii) GCG-like which includes GCG, GLP1, GLP2 and GIP. Conserved regions flanking secretin family members were established by comparative analysis of the Takifugu, Xenopus, chicken and human genomes and gene homologues were identified in nematode, Drosophila and Ciona genomes but no gene linkage occurred. However, in Drosophila and nematode genes which flank vertebrate secretin family members were identified in the same chromosome. Conclusions Receptors of the secretin-like family GPCRs are present in protostomes but no sequence homologues of the vertebrate cognate ligands have been identified. It has not been possible to determine when the ligands evolved but it seems likely that it was after the protostome-deuterostome divergence from an exon that was part of an existing gene or gene fragment by rounds of gene/genome duplication. The duplicate exon under different evolutionary pressures originated the chordate PACAP-like and GCG-like subfamily groups. This event occurred after the emergence of the metazoan secretin GPCRs and led to the establishment of novel peptide-receptor interactions that contributed to the generation of novel physiological functions in the chordate lineage. PMID:20459630

  19. Missing Links: A Serendipitous Journey into Teaching Styles.

    ERIC Educational Resources Information Center

    Worfel, Paul

    This paper documents the journey of a researcher into the teacher effectiveness movement and efforts to find missing links to show the correlations between teacher behavior and student learning. The paper also considers how the forces within education tend to consume embryonic ideas in teacher education, rather than nurture them in an effort to…

  20. Creating Decent Prisons: A Serendipitous Finding about Prison Hospice

    ERIC Educational Resources Information Center

    Wright, Kevin N.; Bronstein, Laura

    2007-01-01

    Limited research has been conducted on the creation or impact of "decent" prisons, institutions where prisoners are treated with care and respect. This study set out to explore organizational factors associated with locating hospice programs into prison settings. Yet, the research produced unexpected findings about the contribution of hospice to…

  1. Serendipitous discovery of the faint solar twin Inti 1

    NASA Astrophysics Data System (ADS)

    Galarza, Jhon Yana; Meléndez, Jorge; Cohen, Judith G.

    2016-05-01

    Context. Solar twins are increasingly the subject of many studies owing to their wide range of applications from testing stellar evolution models to the calibration of fundamental observables; these stars are also of interest because high precision abundances could be achieved that are key to investigating the chemical anomalies imprinted by planet formation. Furthermore, the advent of photometric surveys with large telescopes motivates the identification of faint solar twins in order to set the zero point of fundamental calibrations. Aims: We intend to perform a detailed line-by-line differential analysis to verify whether 2MASS J23263267-0239363 (designated here as Inti 1) is indeed a solar twin. Methods: We determine the atmospheric parameters and differential abundances using high-resolution (R ≈ 50 000), high signal-to-noise (S/N ≈ 110-240 per pixel) Keck/HIRES spectra for our solar twin candidate, the previously known solar twin HD 45184, and the Sun (using reflected light from the asteroid Vesta). Results: For the bright solar twin HD 45184, we found Teff = 5864 ± 9 K, log g = 4.45 ± 0.03 dex, vt = 1.11 ± 0.02 km s-1, and [Fe/H] = 0.04 ± 0.01 dex, which are in good agreement with previous works. Our abundances are in excellent agreement with a recent high-precision work, with an element-to-element scatter of only 0.01 dex. The star Inti 1 has atmospheric parameters Teff = 5837 ± 11 K, log g = 4.42 ± 0.03 dex, vt = 1.04 ± 0.02 km s-1, and [Fe/H] = 0.07 ± 0.01 dex that are higher than solar. The age and mass of the solar twin HD 45184 (3 Gyr and 1.05 M⊙) and the faint solar twin Inti 1 (4 Gyr and 1.04 M⊙) were estimated using isochrones. The differential analysis shows that HD 45184 presents an abundance pattern that is similar to typical nearby solar twins; this means this star has an enhanced refractory relative to volatile elements, while Inti 1 has an abundance pattern closer to solar, albeit somewhat enhanced in refractories. The abundance pattern of HD 45184 and Inti 1 could be reproduced by adding ≈3.5 M⊕ and ≈1.5 M⊕ of Earth-like material to the convective zone of the Sun. Conclusions: The star Inti 1 is a faint solar twin, therefore, it could be used to calibrate the zero points of different photometric systems. The distant solar twin Inti 1 has an abundance pattern similar to the Sun with only a minor enhancement in the refractory elements. It would be important to analyze other distant solar twins to verify whether they share the Sun's abundance pattern or if they are enhanced in refractories, as is the case in the majority of nearby solar twins. The data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation.

  2. Serendipitous Policy Implications from Class-Size-Initiated Inquiry: IAQ?

    ERIC Educational Resources Information Center

    Achilles, C. M.; Prout, Jean; Finn, J. D.; Bobbett, Gordon C.

    The level of carbon dioxide in a classroom can have a significant negative effect on teaching and learning. Carbon dioxide (CO2) level is affected by class size and time of day. Six urban schools were studied to characterize the effects of these three factors on different class sizes. Carbon monoxide, CO2, temperature, and relative humidity…

  3. Serendipitous images of methanol in Comet Levy (1900 XX)

    NASA Technical Reports Server (NTRS)

    Hoban, Susan

    1993-01-01

    Reuter's (1992) model of the IR fluorescence of methanol is used to retrieve a methanol production rate of 3 +/- 1 x 10 exp 26/s and an abundance relative to water of about 0.1 percent. It is argued that calibration is of paramount importance and that a near-simultaneous spectrum is necessary for achieving a reliable estimate of the continuum underlying the emission feature.

  4. Kit for detecting nucleic acid sequences using competitive hybridization probes

    DOEpatents

    Lucas, Joe N.; Straume, Tore; Bogen, Kenneth T.

    2001-01-01

    A kit is provided for detecting a target nucleic acid sequence in a sample, the kit comprising: a first hybridization probe which includes a nucleic acid sequence that is sufficiently complementary to selectively hybridize to a first portion of the target sequence, the first hybridization probe including a first complexing agent for forming a binding pair with a second complexing agent; and a second hybridization probe which includes a nucleic acid sequence that is sufficiently complementary to selectively hybridize to a second portion of the target sequence to which the first hybridization probe does not selectively hybridize, the second hybridization probe including a detectable marker; a third hybridization probe which includes a nucleic acid sequence that is sufficiently complementary to selectively hybridize to a first portion of the target sequence, the third hybridization probe including the same detectable marker as the second hybridization probe; and a fourth hybridization probe which includes a nucleic acid sequence that is sufficiently complementary to selectively hybridize to a second portion of the target sequence to which the third hybridization probe does not selectively hybridize, the fourth hybridization probe including the first complexing agent for forming a binding pair with the second complexing agent; wherein the first and second hybridization probes are capable of simultaneously hybridizing to the target sequence and the third and fourth hybridization probes are capable of simultaneously hybridizing to the target sequence, the detectable marker is not present on the first or fourth hybridization probes and the first, second, third, and fourth hybridization probes each include a competitive nucleic acid sequence which is sufficiently complementary to a third portion of the target sequence that the competitive sequences of the first, second, third, and fourth hybridization probes compete with each other to hybridize to the third portion of the

  5. COMPARISON OF COMPARATIVE GENOMIC HYBRIDIZATIONS TECHNOLOGIES ACROSS MICROARRAY PLATFORMS

    EPA Science Inventory

    Comparative Genomic Hybridization (CGH) measures DNA copy number differences between a reference genome and a test genome. The DNA samples are differentially labeled and hybridized to an immobilized substrate. In early CGH experiments, the DNA targets were hybridized to metaphase...

  6. Quantum technologies with hybrid systems

    PubMed Central

    Kurizki, Gershon; Bertet, Patrice; Kubo, Yuimaru; Mølmer, Klaus; Petrosyan, David; Rabl, Peter; Schmiedmayer, Jörg

    2015-01-01

    An extensively pursued current direction of research in physics aims at the development of practical technologies that exploit the effects of quantum mechanics. As part of this ongoing effort, devices for quantum information processing, secure communication, and high-precision sensing are being implemented with diverse systems, ranging from photons, atoms, and spins to mesoscopic superconducting and nanomechanical structures. Their physical properties make some of these systems better suited than others for specific tasks; thus, photons are well suited for transmitting quantum information, weakly interacting spins can serve as long-lived quantum memories, and superconducting elements can rapidly process information encoded in their quantum states. A central goal of the envisaged quantum technologies is to develop devices that can simultaneously perform several of these tasks, namely, reliably store, process, and transmit quantum information. Hybrid quantum systems composed of different physical components with complementary functionalities may provide precisely such multitasking capabilities. This article reviews some of the driving theoretical ideas and first experimental realizations of hybrid quantum systems and the opportunities and challenges they present and offers a glance at the near- and long-term perspectives of this fascinating and rapidly expanding field. PMID:25737558

  7. Silica-Ceria Hybrid Nanostructures

    SciTech Connect

    Munusamy, Prabhakaran; Sanghavi, Shail P.; Nachimuthu, Ponnusamy; Baer, Donald R.; Thevuthasan, Suntharampillai

    2012-04-25

    A new hybrid material system that consists of ceria attached silica nanoparticles has been developed. Because of the versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and versatile properties of silica and antioxidant properties of ceria nanoparticles, this material system is ideally suited for biomedical applications. The silica particles of size ~50nm were synthesized by the Stöber synthesis method and ceria nanoparticles of size ~2-3nm was attached to the silica surface using a hetrocoagulation method. The presence of silanol groups on the surface of silica particles mediated homogenous nucleation of ceria which were attached to silica surface by Si-O-Ce bonding. The formations of silica-ceria hybrid nanostructures were characterized by X-photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM). The HRTEM image confirms the formation of individual crystallites of ceria nanoparticles attached to the silica surface. The XPS analysis indicates that ceria nanoparticles are chemically bonded to surface of silica and possess mixture of +3 and +4 chemical states.

  8. Hybrid regional air pollution models

    SciTech Connect

    Drake, R.L.

    1980-03-01

    This discussion deals with a family of air quality models for predicting and analyzing the fine particulate loading in the atmosphere, for assessing the extent and degree of visibility impairment, and for determining the potential of pollutants for increasing the acidity of soils and water. The major horizontal scales of interest are from 400km to 2000km; and the time scales may vary from several hours, to days, weeks, and a few months or years, depending on the EPA regulations being addressed. First the role air quality models play in the general family of atmospheric simulation models is described. Then, the characteristics of a well-designed, comprehensive air quality model are discussed. Following this, the specific objectives of this workshop are outlined, and their modeling implications are summarized. There are significant modeling differences produced by the choice of the coordinate system, whether it be the fixed Eulerian system, the moving Lagrangian system, or some hybrid of the two. These three systems are briefly discussed, and a list of hybrid models that are currently in use are given. Finally, the PNL regional transport model is outlined and a number of research needs are listed.

  9. RHO—Radiation Hybrid Ordering

    PubMed Central

    Ben-Dor, Amir; Chor, Benny; Pelleg, Dan

    2000-01-01

    Radiation hybrid (RH) mapping is a somatic cell technique that is used for ordering markers along a chromosome and estimating the physical distances between them. With the advent of this mapping technique, analyzing the experimental data is becoming a challenging and demanding computational task. In this paper we present the software package RHO (radiation hybrid ordering). The package implements a number of heuristics that attempt to order genomic markers along a chromosome, given as input the results of an RH experiment. The heuristics are based on reducing an appropriate optimization problem to the traveling salesman problem (TSP). The reduced optimization problem is either the nonparametric obligate chromosome breaks (OCBs) or the parametric maximum likelihood estimation (MLE). We tested our package on both simulated and publicly available RH data. For synthetic RH data, the reconstructed markers' permutation is very close to the original permutation, even with fairly high error rates. For real data we used the framework markers' data from the Whitehead Institute maps. For most of the chromosomes (18 out of 23), there is a perfect agreement or nearly perfect agreement (reversal of chromosome arm or arms) between our maps and the Whitehead framework maps. For the remaining five chromosomes, our maps improve on the Whitehead framework maps with respect to both optimization criteria, having higher likelihood and fewer breakpoints. For three chromosomes, the results differ significantly (lod score >1.75), with chromosome 2 having the largest improvement (lod score 3.776). PMID:10720577

  10. Electric and hybrid vehicles program

    NASA Astrophysics Data System (ADS)

    1992-05-01

    The Department of Energy's (DOE) Electric and Hybrid Vehicles (EHV) Program is conducting research, development, testing, and evaluation activities to encourage the use of electricity and alternative fuels for transportation. This program supports the expanded DOE involvement as recommended in the National Energy Strategy. The transportation sector is the single largest user of petroleum; it consumed 63 percent of all petroleum used in the United States last year. Only a small fraction (5 percent) of electricity is generated from petroleum. Electric vehicles, which are themselves virtually pollution-free, could play a key role in helping to reduce both urban pollution and our dependence on petroleum imports. The program's goals are to develop, in cooperation with industry, the technology that will lead to the production and introduction of pollution-free electric vehicles into the Nation's transportation fleet and substitute domestic sources of energy for petroleum-based fuels. This report describes progress achieved in developing electric and hybrid vehicle technologies, beginning with highlights of recent accomplishments in FY-91. Detailed descriptions are provided of program activities during FY-91 in the areas of battery, fuel-cell, and propulsion system development, and testing and evaluation of new technology in fleet site operations and in laboratories. In accordance with the reporting requirements of the Act, this annual report contains a status report on incentives and use of foreign components and concludes with a list of publications resulting from the DOE program.

  11. Coherent control in hybrid materials

    NASA Astrophysics Data System (ADS)

    Tian, Chao; Sukharev, Maxim; Malinovskaya, Svetlana

    2013-05-01

    A quickly growing field of hybrid materials is emerging on the base of latest advancements in nanoplasmonic science. Here one merges plasmonics with atomic and molecular physics considering systems comprised of quantum emitters and metal nano-structures. Such systems exhibit a wide variety of new phenomena. It has long been realized that quantum control could be successfully applied to optically active nano-systems. In this paper we explore the ideas of stimulated Raman adiabatic passage (STIRAP) applied to ensembles of atoms optically coupled to plasmonic systems. We demonstrate the implementation of STIRAP as a tool to control scattering, reflection, and transmission properties of hybrid systems. As an example we consider a core-shell silver nanowire with resonantly coupled layer of three-level atoms. A self-consistent model of Maxwell-Liouville-von Neumann equations is implemented that allows taking into account the collective effects between atoms. We show that both linear and nonlinear optical properties of atomic ensembles may be controlled by coupling to plasmonic nano-structures. The work is partially supported by NSF.

  12. Comparative genomic hybridization: an overview.

    PubMed Central

    Houldsworth, J.; Chaganti, R. S.

    1994-01-01

    Comparative genomic hybridization (CGH) is a newly described molecular-cytogenetic assay that globally assays for chromosomal gains and losses in a genomic complement. In this assay, normal human metaphase chromosomes are competitively hybridized with two differentially labeled genomic DNAs (test and reference), which upon fluorescence microscopy, reveal the chromosomal locations of copy number changes in DNA sequences between the two complements. Application of CGH to DNAs extracted from fresh frozen specimens and cell lines of various tumor types has revealed a number of recurring chromosomal gains and losses that were undetected by traditional cytogenetic analysis. Few previously known sites were found to be in higher copy number, or lost by CGH, while many novel amplified regions were identified. These regions warrant further molecular genetic studies aimed at isolating the perturbed genes. Since CGH can also be performed on DNA extracted from formalin-fixed paraffin-embedded archived tumor specimens with few modifications, gains and losses of genetic material can be determined for specimens that would otherwise be unanalyzable. Prospective and retrospective application of CGH to tumor specimens would permit correlative studies to be performed, possibly identifying diagnostic and prognostic indicators of disease. CGH may also have a future role in detection and identification of chromosomal abnormalities in prenatal diagnosis and in dysmorphic anomalies. Images Figure 1 Figure 2 PMID:7992829

  13. Compressible generalized hybrid Monte Carlo

    NASA Astrophysics Data System (ADS)

    Fang, Youhan; Sanz-Serna, J. M.; Skeel, Robert D.

    2014-05-01

    One of the most demanding calculations is to generate random samples from a specified probability distribution (usually with an unknown normalizing prefactor) in a high-dimensional configuration space. One often has to resort to using a Markov chain Monte Carlo method, which converges only in the limit to the prescribed distribution. Such methods typically inch through configuration space step by step, with acceptance of a step based on a Metropolis(-Hastings) criterion. An acceptance rate of 100% is possible in principle by embedding configuration space in a higher dimensional phase space and using ordinary differential equations. In practice, numerical integrators must be used, lowering the acceptance rate. This is the essence of hybrid Monte Carlo methods. Presented is a general framework for constructing such methods under relaxed conditions: the only geometric property needed is (weakened) reversibility; volume preservation is not needed. The possibilities are illustrated by deriving a couple of explicit hybrid Monte Carlo methods, one based on barrier-lowering variable-metric dynamics and another based on isokinetic dynamics.

  14. Coupling hybrid inflation to moduli

    NASA Astrophysics Data System (ADS)

    Brax, Philippe; van de Bruck, Carsten; Davis, Anne-Christine; Davis, Stephen C.

    2006-09-01

    Hybrid inflation can be realized in low energy effective string theory, as described using supergravity. We find that the coupling of moduli to F-term hybrid inflation in supergravity leads to a slope and a curvature for the inflaton potential. The epsi and η parameters receive contributions at tree and one loop level which are not compatible with slow roll inflation. Furthermore the coupling to the moduli sector can even prevent inflation from ending at all. We show that introducing shift symmetries in the inflationary sector and taking the moduli sector to be no-scale removes most of these problems. If the moduli fields are fixed during inflation, as is usually assumed, it appears that viable slow roll inflation can then be obtained with just one fine-tuning of the moduli sector parameters. However, we show this is not a reasonable assumption, and that the small variation of the moduli fields during inflation gives a significant contribution to the effective inflaton potential. This typically implies that ηap-6, although it may be possible to obtain smaller values with heavy fine-tuning.

  15. Hybrid and Electric Advanced Vehicle Systems Simulation

    NASA Technical Reports Server (NTRS)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  16. Computer code for intraply hybrid composite design

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Sinclair, J. H.

    1981-01-01

    A computer program is described for intraply hybrid composite design (INHYD). The program includes several composite micromechanics theories, intraply hybrid composite theories, and a hygrothermomechanical theory. These theories provide INHYD with considerable flexibility and capability which the user can exercise through several available options. Key features and capabilities of INHYD are illustrated through selected samples.

  17. Hybrid Compounding in New Zealand English

    ERIC Educational Resources Information Center

    Degani, Marta; Onysko, Alexander

    2010-01-01

    This study investigates hybrid compound formation of Maori and English terms in present day New Zealand English (NZE). On the background of Maori and English language contact, the phenomenon of hybrid compounding emerges as a process that, on the one hand, symbolizes the vitality of the Maori element in NZE and, on the other hand, marks the…

  18. Flavor evaluation of fresh tangerine hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report describes on-going research on the quality evaluation of tangerines from the CREC breeding program begun in 2006-2007. Twelve of the 43 tangerine hybrids evaluated in 2007 were selected for re-evaluation in 2008, with 9 named commercial cultivars as references, and 8 new hybrids. Fruit w...

  19. The Federal electric and hybrid vehicle program

    NASA Technical Reports Server (NTRS)

    Schwartz, H. J.

    1980-01-01

    The commercial development and use of electric and hybrid vehicles is discussed with respect to its application as a possible alternative transportation system. A market demonstration is described that seeks to place 10,000 electric hybrid vehicles into public and private sector demonstrations.

  20. High power battery systems for hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Corson, Donald W.

    Pure electric and hybrid vehicles have differing demands on the battery system of a vehicle. This results in correspondingly different demands on the battery management of a hybrid vehicle. Examples show the differing usage patterns. The consequences for the battery cells and the battery management are discussed. The importance of good thermal management is underlined.

  1. First-Generation Hybrid Compact Compton Imager

    SciTech Connect

    Cunningham, M; Burks, M; Chivers, D; Cork, C; Fabris, L; Gunter, D; Krings, T; Lange, D; Hull, E; Mihailescu, L; Nelson, K; Niedermayr, T; Protic, D; Valentine, J; Vetter, K; Wright, D

    2005-11-07

    At Lawrence Livermore National Laboratory, we are pursuing the development of a gamma-ray imaging system using the Compton effect. We have built our first generation hybrid Compton imaging system, and we have conducted initial calibration and image measurements using this system. In this paper, we present the details of the hybrid Compton imaging system and initial calibration and image measurements.

  2. The Hybridization of Social Science Knowledge.

    ERIC Educational Resources Information Center

    Dogan, Mattei

    1996-01-01

    Describes the growth of science as a twofold process: (1) the fragmentation of formal disciplines; and (2) a recombination of the specialties resulting from this fragmentation. Discusses the division of disciplines into specialized subfields that has led to the development of hybrid specialties, and maintains that the concept of hybridization is…

  3. NETL's Hybrid Performance, or Hyper, facility

    SciTech Connect

    2013-06-12

    NETL's Hybrid Performance, or Hyper, facility is a one-of-a-kind laboratory built to develop control strategies for the reliable operation of fuel cell/turbine hybrids and enable the simulation, design, and implementation of commercial equipment. The Hyper facility provides a unique opportunity for researchers to explore issues related to coupling fuel cell and gas turbine technologies.

  4. California State University, Northridge: Hybrid Lab Courses

    ERIC Educational Resources Information Center

    EDUCAUSE, 2014

    2014-01-01

    California State University, Northridge's Hybrid Lab course model targets high failure rate, multisection, gateway courses in which prerequisite knowledge is a key to success. The Hybrid Lab course model components incorporate interventions and practices that have proven successful at CSUN and other campuses in supporting students, particularly…

  5. 75 FR 81456 - Hybrid Retirement Plans; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ... were published in the Federal Register on Tuesday, October 19, 2010 (75 FR 64123) providing guidance relating to certain provisions of the Internal Revenue Code that apply to hybrid defined benefit pension... Internal Revenue Service 26 CFR Part 1 RIN 1545-BG36 Hybrid Retirement Plans; Correction AGENCY:...

  6. Sweet Corn Hybrid Disease Nursery - 2009

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report summarizes the reactions of 387 sweet corn hybrids to Stewart’s wilt, common rust, maize dwarf mosaic virus, Southern leaf blight, and Northern leaf blight based on their performance in the University of Illinois sweet corn disease nursery in 2009. The reactions of these hybrids to three...

  7. Evaluating the Pedagogical Potential of Hybrid Models

    ERIC Educational Resources Information Center

    Levin, Tzur; Levin, Ilya

    2013-01-01

    The paper examines how the use of hybrid models--that consist of the interacting continuous and discrete processes--may assist in teaching system thinking. We report an experiment in which undergraduate students were asked to choose between a hybrid and a continuous solution for a number of control problems. A correlation has been found between…

  8. 40 CFR 1036.525 - Hybrid engines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... part and/or 40 CFR part 1065. If you test hybrid engines using the SET, deactivate the hybrid features... state of charge constraints. (1) Map the engine as specified in 40 CFR 1065.510. This requires separate... in CO2 emissions resulting from the power take-off operation as described in 40 CFR 1037.525....

  9. Benefits of Hybrid Classes in Community Colleges

    ERIC Educational Resources Information Center

    Barker, Joel

    2015-01-01

    This article discusses hybrid courses and their impact on educational facilities, their students, and instructors. Instructors now have over ten years of data related to hybrid courses and by trial and error have devised different strategies to plan and execute lesson plans via partly online forums. Programs are in place that give students the…

  10. NETL's Hybrid Performance, or Hyper, facility

    ScienceCinema

    None

    2014-06-26

    NETL's Hybrid Performance, or Hyper, facility is a one-of-a-kind laboratory built to develop control strategies for the reliable operation of fuel cell/turbine hybrids and enable the simulation, design, and implementation of commercial equipment. The Hyper facility provides a unique opportunity for researchers to explore issues related to coupling fuel cell and gas turbine technologies.

  11. Sweet Corn Hybrid Disease Nursery - 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report summarizes the reactions of 439 sweet corn hybrids to Stewart’s wilt, common rust, maize dwarf mosaic virus, Southern leaf blight, and Northern leaf blight based on their performance in the University of Illinois sweet corn disease nursery in 2010. The reactions of these hybrids to two h...

  12. Computer code for intraply hybrid composite design

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Sinclair, J. H.

    1981-01-01

    A computer program has been developed and is described herein for intraply hybrid composite design (INHYD). The program includes several composite micromechanics theories, intraply hybrid composite theories and a hygrothermomechanical theory. These theories provide INHYD with considerable flexibility and capability which the user can exercise through several available options. Key features and capabilities of INHYD are illustrated through selected samples.

  13. Design guidelines for hybrid microcircuits; organic adhesives for hybrid microcircuits

    NASA Technical Reports Server (NTRS)

    Perkins, K. L.; Licari, J. J.

    1975-01-01

    The properties of organic adhesives were studied to acquire an adequate information base to generate a guideline document for the selection of adhesives for use in high reliability hybrid microcircuits. Specific areas covered include: (1) alternate methods for determining the outgassing of cured adhesives; (2) effects of long term aging at 150C on the electrical properties of conductive adhesives; (3) effects of shelf life age on adhesive characteristics; (4) bond strengths of electrically conductive adhesives on thick film gold metallization, (5) a copper filled adhesive; (6) effects of products outgassed from cured adhesives on device electrical parameters; (7) metal migration from electrically conductive adhesives; and (8) ionic content of electrically insulative adhesives. The tests performed during these investigations are described, and the results obtained are discussed in detail.

  14. Silicon nanocrystal-noble metal hybrid nanoparticles.

    PubMed

    Sugimoto, H; Fujii, M; Imakita, K

    2016-06-01

    We report a novel and facile self-limiting synthesis route of silicon nanocrystal (Si NC)-based colloidally stable semiconductor-metal (gold, silver and platinum) hybrid nanoparticles (NPs). For the formation of hybrid NPs, we employ ligand-free colloidal Si NCs with heavily boron (B) and phosphorus (P) doped shells. By simply mixing B and P codoped colloidal Si NCs with metal salts, hybrid NPs consisting of metal cores and Si NC shells are spontaneously formed. We demonstrate the synthesis of highly uniform and size controllable hybrid NPs. It is shown that codoped Si NCs act as a reducing agent for metal salts and also as a protecting layer to stop metal NP growth. The process is thus self-limiting. The development of a variety of Si NC-based hybrid NPs is a promising first step for the design of biocompatible multifunctional NPs with broad material choices for biosensing, bioimaging and solar energy conversion. PMID:27121127

  15. Space and power efficient hybrid counters array

    DOEpatents

    Gara, Alan G.; Salapura, Valentina

    2009-05-12

    A hybrid counter array device for counting events. The hybrid counter array includes a first counter portion comprising N counter devices, each counter device for receiving signals representing occurrences of events from an event source and providing a first count value corresponding to a lower order bits of the hybrid counter array. The hybrid counter array includes a second counter portion comprising a memory array device having N addressable memory locations in correspondence with the N counter devices, each addressable memory location for storing a second count value representing higher order bits of the hybrid counter array. A control device monitors each of the N counter devices of the first counter portion and initiates updating a value of a corresponding second count value stored at the corresponding addressable memory location in the second counter portion. Thus, a combination of the first and second count values provide an instantaneous measure of number of events received.

  16. Space and power efficient hybrid counters array

    DOEpatents

    Gara, Alan G.; Salapura, Valentina

    2010-03-30

    A hybrid counter array device for counting events. The hybrid counter array includes a first counter portion comprising N counter devices, each counter device for receiving signals representing occurrences of events from an event source and providing a first count value corresponding to a lower order bits of the hybrid counter array. The hybrid counter array includes a second counter portion comprising a memory array device having N addressable memory locations in correspondence with the N counter devices, each addressable memory location for storing a second count value representing higher order bits of the hybrid counter array. A control device monitors each of the N counter devices of the first counter portion and initiates updating a value of a corresponding second count value stored at the corresponding addressable memory location in the second counter portion. Thus, a combination of the first and second count values provide an instantaneous measure of number of events received.

  17. Flexural performance of woven hybrid composites

    NASA Astrophysics Data System (ADS)

    Maslinda, A. B.; Majid, M. S. Abdul; Dan-mallam, Y.; Mazawati, M.

    2016-07-01

    This paper describes the experimental investigation of the flexural performance of natural fiber reinforced polymer composites. Hybrid composites consist of interwoven kenaf/jute and kenaf/hemp fibers was prepared by infusion process using epoxy as polymer matrix. Woven kenaf, jute and hemp composites were also prepared for comparison. Both woven and hybrid composites were subjected to three point flexural test. From the result, bending resistance of hybrid kenaf/jute and kenaf/hemp composites was higher compared to their individual fiber. Hybridization with high strength fiber such as kenaf enhanced the capability of jute and hemp fibers to withstand bending load. Interlocking between yarns in woven fabric make pull out fibers nearly impossible and increase the flexural performance of the hybrid composites.

  18. Evaluation of a Hybrid Elastic EVA Glove

    NASA Technical Reports Server (NTRS)

    Korona, F. Adam; Akin, David

    2002-01-01

    The hybrid elastic design is based upon an American Society for Engineering Education (ASEE) glove designed by at the Space Systems Laboratory (SSL) in 1985. This design uses an elastic restraint layer instead of convolute joints to achieve greater dexterity and mobility during EVA (extravehicular activity). Two pilot studies and a main study were conducted using the hybrid elastic glove and 4000-series EMU (extravehicular activity unit) glove. Data on dexterity performance, joint range of motion, grip strength and perceived exertion was assessed for the EMU and hybrid elastic gloves with correlations to a barehanded condition. During this study, 30 test subjects performed multiple test sessions using a hybrid elastic glove and a 4000- series shuttle glove in a 4.3psid pressure environment. Test results to date indicate that the hybrid elastic glove performance is approximately similar to the performance of the 4000-series glove.

  19. Coumarin hybrids as novel therapeutic agents.

    PubMed

    Sandhu, Sonali; Bansal, Yogita; Silakari, Om; Bansal, Gulshan

    2014-08-01

    Naturally occurring coumarins, having wide spectrum of activities such as antioxidant, anti-inflammatory, anticancer, MAO-B inhibitory and antimicrobial, are frequently used by the researchers to develop novel synthetic and semisynthetic coumarin based therapeutic agents. Many of these agents are hybrid molecules, which are designed through concept of molecular hybridization and have shown multiple pharmacological activities. This multifunctional attribute of these hybrid compounds makes them potential drug candidates for the treatment of multifactorial diseases such as cancer, Alzheimer's disease, metabolic syndromes, AIDS, malaria, and cardiovascular diseases. The present review compiles research reports on development of different coumarin hybrids, classify these on the basis of their therapeutic uses and propose structure-activity relationships. It is intended to help medicinal chemist in designing and synthesizing novel and potent hybrid compounds for the treatment of different disorders. PMID:24934993

  20. Mechanical property characterization of intraply hybrid composites

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Lark, R. F.; Sinclair, J. H.

    1979-01-01

    An investigation of the mechanical properties of intraply hybrids made from graphite fiber/epoxy matrix hybridized with secondary S-glass or Kevlar 49 fiber composites is presented. The specimen stress-strain behavior was determined, showing that mechanical properties of intraply hybrid composites can be measured with available methods such as the ten-degree off-axis test for intralaminar shear, and conventional tests for tensile, flexure, and Izod impact properties. The results also showed that combinations of high modulus graphite/S-glass/epoxy matrix composites exist which yield intraply hybrid laminates with the best 'balanced' properties, and that the translation efficiency of mechanical properties from the constituent composites to intraply hybrids may be assessed with a simple equation.

  1. Ultra-thin microporous/hybrid materials

    DOEpatents

    Jiang, Ying-Bing; Cecchi, Joseph L.; Brinker, C. Jeffrey

    2012-05-29

    Ultra-thin hybrid and/or microporous materials and methods for their fabrication are provided. In one embodiment, the exemplary hybrid membranes can be formed including successive surface activation and reaction steps on a porous support that is patterned or non-patterned. The surface activation can be performed using remote plasma exposure to locally activate the exterior surfaces of porous support. Organic/inorganic hybrid precursors such as organometallic silane precursors can be condensed on the locally activated exterior surfaces, whereby ALD reactions can then take place between the condensed hybrid precursors and a reactant. Various embodiments can also include an intermittent replacement of ALD precursors during the membrane formation so as to enhance the hybrid molecular network of the membranes.

  2. Hybrid selection as a method of increasing mapping power for radiation hybrids.

    PubMed

    Jones, H B

    1996-08-01

    Radiation hybrids have become a widely used tool for physical mapping. A drawback of the technique is that large numbers of hybrids are required to construct robust, high-resolution maps. The information contained within a panel of radiation hybrids is limited by the frequency of retention of chromosomal fragments from the donor cell line. In almost all experiments to date, the retention frequency has been below the optimal level; therefore, many hybrids are needed to produce high-quality maps. Because of the labor-intensive nature of large-scale mapping projects, it is important to make panels as small as possible. One method that has been adopted is to produce initially a large number of hybrids that are all typed with a few loci. Those hybrids showing satisfactorily high retention are admitted to the final panel and the rest are discarded. In this way, a panel of radiation hybrids with higher than expected retention can be created. Methods for conducting such a selection regime are discussed. To investigate the potential advantages of selecting hybrids based on their retention frequency, simulations were run under a variety of conditions. As expected panels with high retention (40%) provided better mapping resources than panels with lower (20%) retention. Beginning with an initial panel of 200 hybrids, comparisons of a random sample of 100 hybrids and the set of those 100 hybrids showing the highest marker retention demonstrated that selection may not be always the best strategy despite the increase in mean retention it yields. The selection of hybrids containing large numbers of fragments leads to an overestimation of the frequency of radiation-induced breaks. When breaks occur with high frequency (for example, when high radiation doses are used), the selection of hybrids leads to a loss of linkage and hence an inability to order the markers. As such, the merits of screening hybrids depends on both the radiation dose and the desired map resolution. PMID:8858351

  3. Hybridization and Selective Release of DNA Microarrays

    SciTech Connect

    Beer, N R; Baker, B; Piggott, T; Maberry, S; Hara, C M; DeOtte, J; Benett, W; Mukerjee, E; Dzenitis, J; Wheeler, E K

    2011-11-29

    DNA microarrays contain sequence specific probes arrayed in distinct spots numbering from 10,000 to over 1,000,000, depending on the platform. This tremendous degree of multiplexing gives microarrays great potential for environmental background sampling, broad-spectrum clinical monitoring, and continuous biological threat detection. In practice, their use in these applications is not common due to limited information content, long processing times, and high cost. The work focused on characterizing the phenomena of microarray hybridization and selective release that will allow these limitations to be addressed. This will revolutionize the ways that microarrays can be used for LLNL's Global Security missions. The goals of this project were two-fold: automated faster hybridizations and selective release of hybridized features. The first study area involves hybridization kinetics and mass-transfer effects. the standard hybridization protocol uses an overnight incubation to achieve the best possible signal for any sample type, as well as for convenience in manual processing. There is potential to significantly shorten this time based on better understanding and control of the rate-limiting processes and knowledge of the progress of the hybridization. In the hybridization work, a custom microarray flow cell was used to manipulate the chemical and thermal environment of the array and autonomously image the changes over time during hybridization. The second study area is selective release. Microarrays easily generate hybridization patterns and signatures, but there is still an unmet need for methodologies enabling rapid and selective analysis of these patterns and signatures. Detailed analysis of individual spots by subsequent sequencing could potentially yield significant information for rapidly mutating and emerging (or deliberately engineered) pathogens. In the selective release work, optical energy deposition with coherent light quickly provides the thermal energy to

  4. Hybrid Composite Cryogenic Tank Structure

    NASA Technical Reports Server (NTRS)

    DeLay, Thomas

    2011-01-01

    A hybrid lightweight composite tank has been created using specially designed materials and manufacturing processes. The tank is produced by using a hybrid structure consisting of at least two reinforced composite material systems. The inner composite layer comprises a distinct fiber and resin matrix suitable for cryogenic use that is a braided-sleeve (and/or a filamentwound layer) aramid fiber preform that is placed on a removable mandrel (outfitted with metallic end fittings) and is infused (vacuum-assisted resin transfer molded) with a polyurethane resin matrix with a high ductility at low temperatures. This inner layer is allowed to cure and is encapsulated with a filamentwound outer composite layer of a distinct fiber resin system. Both inner and outer layer are in intimate contact, and can also be cured at the same time. The outer layer is a material that performs well for low temperature pressure vessels, and it can rely on the inner layer to act as a liner to contain the fluids. The outer layer can be a variety of materials, but the best embodiment may be the use of a continuous tow of carbon fiber (T-1000 carbon, or others), or other high-strength fibers combined with a high ductility epoxy resin matrix, or a polyurethane matrix, which performs well at low temperatures. After curing, the mandrel can be removed from the outer layer. While the hybrid structure is not limited to two particular materials, a preferred version of the tank has been demonstrated on an actual test tank article cycled at high pressures with liquid nitrogen and liquid hydrogen, and the best version is an inner layer of PBO (poly-pphenylenebenzobisoxazole) fibers with a polyurethane matrix and an outer layer of T-1000 carbon with a high elongation epoxy matrix suitable for cryogenic temperatures. A polyurethane matrix has also been used for the outer layer. The construction method is ideal because the fiber and resin of the inner layer has a high strain to failure at cryogenic

  5. Nanorice Particles: Hybrid Plasmonic Nanostructures

    NASA Technical Reports Server (NTRS)

    Wang, Hui (Inventor); Brandl, Daniel (Inventor); Le, Fei (Inventor); Nordlander, Peter (Inventor); Halas, Nancy J. (Inventor)

    2010-01-01

    A new hybrid nanoparticle, i.e., a nanorice particle, which combines the intense local fields of nanorods with the highly tunable plasmon resonances of nanoshells, is described herein. This geometry possesses far greater structural tunability than previous nanoparticle geometries, along with much larger local field enhancements and far greater sensitivity as a surface plasmon resonance (SPR) nanosensor than presently known dielectric-conductive material nanostructures. In an embodiment, a nanoparticle comprises a prolate spheroid-shaped core having a first aspect ratio. The nanoparticle also comprises at least one conductive shell surrounding said prolate spheroid-shaped core. The nanoparticle has a surface plasmon resonance sensitivity of at least 600 nm RIU(sup.-1). Methods of making the disclosed nanorice particles are also described herein.

  6. Hybrid inflation along waterfall trajectories

    SciTech Connect

    Clesse, Sebastien

    2011-03-15

    We identify a new inflationary regime for which more than 60 e-folds are generated classically during the waterfall phase occurring after the usual hybrid inflation. By performing a Bayesian Monte-Carlo-Markov-Chain analysis, this scenario is shown to take place in a large part of the parameter space of the model. When this occurs, the observable perturbation modes leave the Hubble radius during waterfall inflation. The power spectrum of adiabatic perturbations is red, possibly in agreement with CMB constraints. Particular attention has been given to study only the regions for which quantum backreactions do not affect the classical dynamics. Implications concerning the preheating and the absence of topological defects in our Universe are discussed.

  7. Optoplasmonics: hybridization in 3D

    NASA Astrophysics Data System (ADS)

    Rosa, L.; Gervinskas, G.; Žukauskas, A.; Malinauskas, M.; Brasselet, E.; Juodkazis, S.

    2013-12-01

    Femtosecond laser fabrication has been used to make hybrid refractive and di ractive micro-optical elements in photo-polymer SZ2080. For applications in micro- uidics, axicon lenses were fabricated (both single and arrays), for generation of light intensity patterns extending through the entire depth of a typically tens-of-micrometers deep channel. Further hybridisation of an axicon with a plasmonic slot is fabricated and demonstrated nu- merically. Spiralling chiral grooves were inscribed into a 100-nm-thick gold coating sputtered over polymerized micro-axicon lenses, using a focused ion beam. This demonstrates possibility of hybridisation between optical and plasmonic 3D micro-optical elements. Numerical modelling of optical performance by 3D-FDTD method is presented.

  8. Hybrid Multifoil Aerogel Thermal Insulation

    NASA Technical Reports Server (NTRS)

    Sakamoto, Jeffrey; Paik, Jong-Ah; Jones, Steven; Nesmith, Bill

    2008-01-01

    This innovation blends the merits of multifoil insulation (MFI) with aerogel-based insulation to develop a highly versatile, ultra-low thermally conductive material called hybrid multifoil aerogel thermal insulation (HyMATI). The density of the opacified aerogel is 240 mg/cm3 and has thermal conductivity in the 20 mW/mK range in high vacuum and 25 mW/mK in 1 atmosphere of gas (such as argon) up to 800 C. It is stable up to 1,000 C. This is equal to commercially available high-temperature thermal insulation. The thermal conductivity of the aerogel is 36 percent lower compared to several commercially available insulations when tested in 1 atmosphere of argon gas up to 800 C.

  9. Engineering semiconductor hybrids for sensing

    NASA Astrophysics Data System (ADS)

    Gumbs, Godfrey; Iurov, Andrii; Huang, Danhong

    2016-06-01

    The effect of screening of the coulomb interaction between two layers of two-dimensional electrons, such as in graphene, by a highly doped semiconducting substrate is investigated. We employ the random-phase approximation to calculate the dispersion equation of this hybrid structure in order to determine the plasmon excitation spectrum. When an electric current is passed through a layer, the low-frequency plasmons in the layer may bifurcate into separate streams due to the current-driving effect. At a critical wave vector, determined by the separation between layers and their distance from the surface, their phase velocities may be in opposite directions and a surface plasmon instability leads to the emission of radiation. Applications to detectors and other electromagnetic devices exploiting nano-plasmonics are discussed.

  10. Hybrid Epithelioid Schwannoma/Perineurioma.

    PubMed

    Kacerovska, Denisa; Michal, Michal; Kazakov, Dmitry V

    2016-07-01

    We report a case of a 58-year-old who woman presented with a solitary slowly growing subcutaneous nodule covered by normally appearing skin on her left groin. Microscopically, the lesion was well circumscribed but unencapsulated, and showed biphasic cellular differentiation. One cell population was presented by small rounded (epithelioid) cells arranged singly, in small aggregates or short cords, whereas the second one was composed of cells with slender nuclei and delicate elongated bipolar cytoplasmic processes. On immunohistochemistry, the epithelioid component showed positive reaction for S-100 protein and negative for epithelial membrane antigen (EMA), thus compatible with schwannian differentiation and resembling epithelioid schwannoma. The other component showed a reverse immunophenotype being S-100 protein negative and EMA positive, thus corresponding to perineuriomatous differentiation. The clinicopathologic and immunohistochemical features of the lesion were compatible with hybrid epithelioid schwannoma/perineurioma, a rare morphological variant of peripheral nerve sheath tumors. PMID:26863063

  11. Stellarmak a hybrid stellarator: Spheromak

    SciTech Connect

    Hartman, C.W.

    1980-01-04

    This paper discusses hybridization of modified Stellarator-like transform windings (T-windings) with a Spheromak or Field-Reversed-Mirror configuration. This configuration, Stellarmak, retains the important topological advantage of the Spheromak or FRM of having no plasma linking conductors or blankets. The T-windings provide rotational transformation in toroidal angle of the outer poloidal field lines, in effect creating a reversed B/sub Toroidal/ Spheromak or adding average B/sub T/ to the FRM producing higher shear, increased limiting ..beta.., and possibly greater stability to kinks and tilt. The presence of field ripple in the toroidal direction may be sufficient to inhibit cancellation of directed ion current by electron drag to allow steady state operation with the toroidal as well as poloidal current maintained by neutral beams.

  12. Quantum photonics hybrid integration platform

    SciTech Connect

    Murray, E.; Floether, F. F.; Ellis, D. J. P.; Meany, T.; Bennett, A. J. Shields, A. J.; Lee, J. P.; Griffiths, J. P.; Jones, G. A. C.; Farrer, I.; Ritchie, D. A.

    2015-10-26

    Fundamental to integrated photonic quantum computing is an on-chip method for routing and modulating quantum light emission. We demonstrate a hybrid integration platform consisting of arbitrarily designed waveguide circuits and single-photon sources. InAs quantum dots (QD) embedded in GaAs are bonded to a SiON waveguide chip such that the QD emission is coupled to the waveguide mode. The waveguides are SiON core embedded in a SiO{sub 2} cladding. A tuneable Mach Zehnder interferometer (MZI) modulates the emission between two output ports and can act as a path-encoded qubit preparation device. The single-photon nature of the emission was verified using the on-chip MZI as a beamsplitter in a Hanbury Brown and Twiss measurement.

  13. Heterogeneous fuel for hybrid rocket

    NASA Technical Reports Server (NTRS)

    Stickler, David B. (Inventor)

    1996-01-01

    Heterogeneous fuel compositions suitable for use in hybrid rocket engines and solid-fuel ramjet engines, The compositions include mixtures of a continuous phase, which forms a solid matrix, and a dispersed phase permanently distributed therein. The dispersed phase or the matrix vaporizes (or melts) and disperses into the gas flow much more rapidly than the other, creating depressions, voids and bumps within and on the surface of the remaining bulk material that continuously roughen its surface, This effect substantially enhances heat transfer from the combusting gas flow to the fuel surface, producing a correspondingly high burning rate, The dispersed phase may include solid particles, entrained liquid droplets, or gas-phase voids having dimensions roughly similar to the displacement scale height of the gas-flow boundary layer generated during combustion.

  14. Acoustic metasurface with hybrid resonances.

    PubMed

    Ma, Guancong; Yang, Min; Xiao, Songwen; Yang, Zhiyu; Sheng, Ping

    2014-09-01

    An impedance-matched surface has the property that an incident wave generates no reflection. Here we demonstrate that by using a simple construction, an acoustically reflecting surface can acquire hybrid resonances and becomes impedance-matched to airborne sound at tunable frequencies, such that no reflection is generated. Each resonant cell of the metasurface is deep-subwavelength in all its spatial dimensions, with its thickness less than the peak absorption wavelength by two orders of magnitude. As there can be no transmission, the impedance-matched acoustic wave is hence either completely absorbed at one or multiple frequencies, or converted into other form(s) of energy, such as an electrical current. A high acoustic-electrical energy conversion efficiency of 23% is achieved. PMID:24880731

  15. Construction of radiation hybrid panels.

    PubMed

    Page, John E; Murphy, William J

    2008-01-01

    Whole-genome radiation hybrid (RH) mapping has proven to be a powerful tool for mapping genes and comparing genome architecture. We describe a protocol for constructing RH panels by rescuing irradiated fibroblast donor cells of any mammalian species by polyethylene glycol fusion to a thymidine kinase-deficient hamster cell line. Characterization and expansion of a panel of 90-100 cell lines can be used to map virtually any PCR-based marker that can be distinguished from the recipient hamster genome. The described procedure has been used successfully to create RH panels from diverse mammalian species such as macaques, elephants, alpacas, and armadillos, and may be applicable to nonmammalian vertebrates as well. PMID:18629660

  16. An IIR median hybrid filter

    NASA Technical Reports Server (NTRS)

    Bauer, Peter H.; Sartori, Michael A.; Bryden, Timothy M.

    1992-01-01

    A new class of nonlinear filters, the so-called class of multidirectional infinite impulse response median hybrid filters, is presented and analyzed. The input signal is processed twice using a linear shift-invariant infinite impulse response filtering module: once with normal causality and a second time with inverted causality. The final output of the MIMH filter is the median of the two-directional outputs and the original input signal. Thus, the MIMH filter is a concatenation of linear filtering and nonlinear filtering (a median filtering module). Because of this unique scheme, the MIMH filter possesses many desirable properties which are both proven and analyzed (including impulse removal, step preservation, and noise suppression). A comparison to other existing median type filters is also provided.

  17. Permutation on hybrid natural inflation

    NASA Astrophysics Data System (ADS)

    Carone, Christopher D.; Erlich, Joshua; Ramos, Raymundo; Sher, Marc

    2014-09-01

    We analyze a model of hybrid natural inflation based on the smallest non-Abelian discrete group S3. Leading invariant terms in the scalar potential have an accidental global symmetry that is spontaneously broken, providing a pseudo-Goldstone boson that is identified as the inflaton. The S3 symmetry restricts both the form of the inflaton potential and the couplings of the inflaton field to the waterfall fields responsible for the end of inflation. We identify viable points in the model parameter space. Although the power in tensor modes is small in most of the parameter space of the model, we identify parameter choices that yield potentially observable values of r without super-Planckian initial values of the inflaton field.

  18. Dark energy in hybrid inflation

    SciTech Connect

    Gong, Jinn-Ouk; Kim, Seongcheol

    2007-03-15

    The situation that a scalar field provides the source of the accelerated expansion of the Universe while rolling down its potential is common in both the simple models of the primordial inflation and the quintessence-based dark energy models. Motivated by this point, we address the possibility of causing the current acceleration via the primordial inflation using a simple model based on hybrid inflation. We trigger the onset of the motion of the quintessence field via the waterfall field, and find that the fate of the Universe depends on the true vacuum energy determined by choosing the parameters. We also briefly discuss the variation of the equation of state and the possible implementation of our scenario in supersymmetric theories.

  19. Sensitivity, Specificity, and the Hybridization Isotherms of DNA Chips

    PubMed Central

    Halperin, A.; Buhot, A.; Zhulina, E.B.

    2004-01-01

    Competitive hybridization, at the surface and in the bulk, lowers the sensitivity of DNA chips. Competitive surface hybridization occurs when different targets can hybridize with the same probe. Competitive bulk hybridization takes place when the targets can hybridize with free complementary chains in the solution. The effects of competitive hybridization on the thermodynamically attainable performance of DNA chips are quantified in terms of the hybridization isotherms of the spots. These relate the equilibrium degree of the hybridization to the bulk composition. The hybridization isotherm emerges as a Langmuir isotherm modified for electrostatic interactions within the probe layer. The sensitivity of the assay in equilibrium is directly related to the slope of the isotherm. A simpler description is possible, in terms of c50 values specifying the bulk composition corresponding to 50% hybridization at the surface. The effects of competitive hybridization are important for the quantitative analysis of DNA chip results, especially when used to study point mutations. PMID:14747310

  20. Hybrid electric vehicles in Europe and Japan

    SciTech Connect

    Wyczalek, F.A.

    1996-12-31

    Beginning in 1990, the major automotive passenger vehicle manufacturers once again reexamined the battery powered electric vehicle (EV). This intensive effort to reduce the battery EV to commercial practice focused attention on the key issue of limited vehicle range, resulting from the low energy density and high mass characteristics of batteries, in comparison to liquid hydrocarbon fuels. Consequently, by 1995, vehicle manufacturers turned their attention to hybrid electric vehicles (HEV). This redirection of EV effort is highlighted by the focus on experimental hybrid EV displayed at the 1995 Frankfurt Motor Show and the Tokyo Motor Show in Japan. In Europe the 56th IAA in Frankfurt included twelve or more EV designed for personnel transportation, and among them, two featured hybrid-electric (HEV) systems: the Peugeot turboelectric HEV, and the Opel Ermscher Selectra HEV. In Japan, at the 31st Tokyo Motor Show, among the twenty or more EV on display, seven were hybrid HEV by: Daihatsu, Mitsubishi, Toyota: and, the Suburu, Suzuki, and the Kia KEV4 parallel type HEV. This paper presents a comparative analysis of the key features of these hybrid propulsion systems. Among the conclusions, two issues are evident: one, the focus is on series-type hybrid systems, with the exception of the parallel Suburu and Suzuki HEV, and, two, the major manufacturers are turning to the hybrid concept in their search for solutions to two key EV Issues: limited driving range; and, heating and air conditioning, associated with the low energy density characteristic of batteries.