WorldWideScience

Sample records for wageningen barn reactor

  1. Arabidopsis in Wageningen

    NARCIS (Netherlands)

    Koornneef, M.

    2013-01-01

    Arabidopsis thaliana is the plant species that in the past 25 years has developed into the major model species in plant biology research. This was due to its properties such as short generation time, its small genome and its easiness to be transformed. Wageningen University has played an important r

  2. The Wageningen Rainfall Simulator

    NARCIS (Netherlands)

    Lassu, Tamas; Seeger, K.M.; Peters, P.D.; Keesstra, S.D.

    2015-01-01

    The set-up and characterisation of an indoor nozzle-type rainfall simulator (RS) at Wageningen University, the Netherlands, are presented. It is equipped with four Lechler nozzles (two nr. 460·788 and two nr. 461·008). The tilting irrigation plot is 6 m long and 2·5 m wide. An electrical pump

  3. Graanadventieven in en om Wageningen

    NARCIS (Netherlands)

    Jansen, M.T.; Muller, F.M.

    1963-01-01

    Het graan bestemd voor de vele pluimveebedrijven in de zuidelijke Gelderse Vallei en op een deel van de Veluwe wordt doorgaans per schip te Wageningen aangevoerd en, via het overslagbedrijf aldaar, losgestort per vrachtauto verder vervoerd. Geen wonder dat, als de omstandigheden gunstig zijn, bij de

  4. Samenwerking Wageningen UR met: Faculteit Diergeneeskunde Universiteit Utrecht

    NARCIS (Netherlands)

    Noorduyn, L.

    2008-01-01

    Wageningen UR werkt in haar onderzoeksprogramma’s samen met andere kennis - instellingen. Zo werkt Wageningen UR samen met de Universiteit van Utrecht bij het ontwikkelen van het welzijnsprogramma op het gebied van gezelschapsdieren

  5. Wageningen UR : the centre for the Biobased Economy

    NARCIS (Netherlands)

    Gennip, van E.; Toussaint, H.A.J.M.

    2011-01-01

    With its research and education, Wageningen UR has a central position in the Biobased Economy. Wageningen UR develops applications and solutions that combine technical innovation and social-economic value. Wageningen UR does this together with partners in the private sector, the public sector and

  6. Vrijetijdsbesteding te Wageningen 1971 [Ways of spending leisure time in Wageningen 1971

    NARCIS (Netherlands)

    Kloeze, te J.W.

    1971-01-01

    Watching television football game, other sport / reading books / going to pub, restaurant, dancing, disco bar, party, movies, performances ( theatre ) / making music / sports, hobbies / lack of recreation possibilities in Wageningen. Background variables: basic characteristics/ household characteris

  7. Vrijetijdsbesteding te Wageningen 1971 [Ways of spending leisure time in Wageningen 1971

    NARCIS (Netherlands)

    Kloeze, te J.W.

    2007-01-01

    Watching television football game, other sport / reading books / going to pub, restaurant, dancing, disco bar, party, movies, performances ( theatre ) / making music / sports, hobbies / lack of recreation possibilities in Wageningen. Background variables: basic characteristics/ household

  8. Report Open Course Programme Wageningen UR, 2010

    NARCIS (Netherlands)

    Hijweege, W.L.; Dorp, van M.

    2011-01-01

    Annually, the Wageningen UR open course programme for mid-career professionals provides some six hundred individuals with the opportunity to update their competencies and insights. EL&I co-finances this course programme with the aim to maintain close linkages with international policy priorities

  9. Summer field work in Utrecht and Wageningen

    NARCIS (Netherlands)

    Klemm, W.

    2013-01-01

    Fieldwork completed in summer 2013 for PhD research project "Green Infrastructure for climate-proof "Cities" Summer field work in Utrecht and Wageningen By Wiebke Klemm In summer 2013 I completed the fieldwork for my research 'Green infrastructure for climate-proof cities'. After I had investigated

  10. Interannual variability of global radiation at Wageningen

    Science.gov (United States)

    Kane, R. P.

    1997-11-01

    A spectral analysis of the 12-monthly running means of the global radiation ratio Krobserved at Wageningen (52°N, 6°E) showed significant QBO, QTO (Quasi-biennial and Quasi-triennial Oscillations) and higher periodicities, with the strongest peak at ca.22 years but none at the solar cycle (11 years). All these are probably due to similar periodicities in cloudiness.

  11. Kenniscentrum Wageningen: het gaat ervan komen. Samenvoeging LUW en onderzoekinstituten.

    NARCIS (Netherlands)

    Vries, de A.Ph.

    1997-01-01

    De samenvoeging van de Landbouwuniversiteit en de instituten van de Directie Landbouwkundig Onderzoek (DLO), enkele kleinere kennisinstellingen, alsmede delen van het praktijkonderzoek tot een Kenniscentrum Wageningen

  12. Wageningen Evaluating Programmes for Analytical Laboratories (WEPAL).

    Science.gov (United States)

    van Dijk, D; Houba, V J

    1999-03-01

    The paper describes three of the Wageningen Evaluating Programmes for Analytical Laboratories (WEPAL). These include the analyses of numerous compounds and elements and different parameters such as inorganic chemical composition, organic matter, polycyclic hydrocarbons (PAH), polychlorinated biphenyls (PCB), organochlorine pesticides, some herbicides, heavy metals, particle size, and so on in soil, sediment, compost, manure, and sludge. One programme includes the analysis of inorganic chemical composition, nutritional values, and selected vitamins and amino acids in plant samples. Finally, the paper describes how the results are reported and statistically evaluated.

  13. Climate Research Wageningen UR : Projects, researchers and expertise

    NARCIS (Netherlands)

    Loon-Steensma, van J.M.; Vellinga, P.; Remme, R.

    2009-01-01

    Wageningen UR focuses not only on the global climate system but also on regional and local climate phenomena, taking both scientific and social aspects into account in an integral way. Wageningen UR wants to play an effective role in the transition to a world that is both climate neutral and climate

  14. Samenwerking Wageningen UR met BayerCropScience

    NARCIS (Netherlands)

    Wijsmuller, J.

    2010-01-01

    Wageningen UR werkt in haar onderzoeksprogramma’s samen met andere kennisinstellingen. In dit artikel een nadere kennismaking meteen van deze partners: Bayer CropsScience. Bayer CropScience ontwikkelt bestrijdingsmiddelen voor de Nederlandse markt.

  15. Zorg rond zwangerschap, bevalling en kraambed in Wageningen 1979 [Care for pregnancy, delivery, childbed in city of Wageningen 1979

    NARCIS (Netherlands)

    Brouwer, M.

    1981-01-01

    Description of situation concerning care of pregnancy, childbirth and childbed in Wageningen, the Netherlands. Diagnosis of pregnancy / supervision of pregnancy ( zwangerschapsbegeleiding ) / place of delivery / maternity home / controls of pregnancy / gymnastics course for parents / evaluation of

  16. Zorg rond zwangerschap, bevalling en kraambed in Wageningen 1979 [Care for pregnancy, delivery, childbed in city of Wageningen 1979

    NARCIS (Netherlands)

    Brouwer, M.

    1979-01-01

    Description of situation concerning care of pregnancy, childbirth and childbed in Wageningen, the Netherlands. Diagnosis of pregnancy / supervision of pregnancy ( zwangerschapsbegeleiding ) / place of delivery / maternity home / controls of pregnancy / gymnastics course for parents / evaluation of p

  17. The 'Wageningen School' and the Counterintuituve Sublime

    Directory of Open Access Journals (Sweden)

    Paul Roncken

    2004-06-01

    Full Text Available Preponderance of the great, taming power of the small. Dealing with historic and indigenous culture-related design issues seems to trigger some weak aspects of garden and landscape architecture. This is especially the case in the Dutch "Wageningen School" landscape architecture that is firmly rooted in a causal description of natural and social relationships. Together with the increasing number and broadening interests of parties involved in a design trajectory, the traditional causality cannot handle the demand for more expressive aesthetics. It may lead to aesthetic ambiguity and even a crisis of the legitimation of identity and the identity of a design. But is it really necessary for a landscape architect to let go of the causal theorem in order to be flexible to the (subjective demands of clients and the public? Is there an alternative perspective on the relationship between causality and aesthetics that can have a firm grip on an insatiable discussion regarding identity and legitimation? And can this alternative expand the design language beside the current nostalgia that flourishes in historic and indigenous design issues? Odd as it may seem, the condition postmoderne as described by the French philosopher François Lyotard can make a difference regarding this discussion.

  18. Mor-barn samspillet

    DEFF Research Database (Denmark)

    Røhder, Katrine; Davidsen, Kirstine Agnete; Trier, Christopher Høier;

    2015-01-01

    Denne artikel beskæftiger sig med, hvordan risiko og modstandsdygtighed overføres fra forældre til barn, når mor lider af en alvorlig psykisk lidelse. Vi vil argumentere for, at det er helt centralt at undersøge forældre-barn relationen og det tidlige samspil, hvis man vil forstå spædbarnets...

  19. Analysis of journal usage by Wageningen UR staff members via article references

    NARCIS (Netherlands)

    Veller, van M.G.P.

    2013-01-01

    The research activities of Wageningen University and Research (or Wageningen UR) are concentrated around food and food production, living environment and health, lifestyle and livelihood. To facilitate the scientific information access of Wageningen UR staff members, the library strives to provide a

  20. Systems Approaches and Simulation in Curricular Programs: The Wageningen Experience.

    Science.gov (United States)

    van Dam, A. M.; And Others

    1997-01-01

    Wageningen Agricultural University's use of systems approaches and simulation for undergraduate, graduate, and postgraduate education suggests the following elements are necessary: (1) congruence between the aims/interests of teachers and participants; (2) appropriate course level; (3) applicability to relevant research fields; and (4) a range of…

  1. Initiative for Transformative Sustainability Education at Wageningen University, The Netherlands

    Science.gov (United States)

    Wals, Arjen E. J.

    2011-01-01

    In this article, the author talks about a student-initiated Initiative for Transformative Sustainability Education (ITSE) at Wageningen University in The Netherlands which has led to the development of an undergraduate minor called Sustainability-in-Action consisting of four interlinked courses. When formally approved, the minor will be offered…

  2. Progress Report Open Course Programme Wageningen UR, 2012

    NARCIS (Netherlands)

    Hijweege, W.L.

    2013-01-01

    Annually, the Wageningen UR open course programme for mid-career professionals provides some six hundred individuals with the opportunity to update their competencies and insights. The Ministry of Economic Affairs co-finances this course programme with the aim to maintain the courses’ close linkages

  3. Reactors

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1988-01-01

    This standard applies to the following types of reactors: shunt reactors, current-limiting reactors including neutral-earthing reactors, damping reactors, tuning (filter) reactors, earthing transformers (neutral couplers), arc-suppression reactors, smoothing reactors, with the exception of the following reactors: small reactors with a rating generally less than 2 kvar single-phase and 10 kvar three-phase, reactors for special purposes such as high-frequency line traps or reactors mounted on rolling stock.

  4. Det postmoderne barn

    DEFF Research Database (Denmark)

    Hansen, Ole Henrik

    2010-01-01

    Den nye psykologi fokuserer på dynamik og intersubjektivitet, mens den gamle var optaget af faser og udviklingstrin. Den postmoderne forståelse af det lille barn opfatter ikke faserne som aflåste, historiske sandheder, men som levende narrativer. Og så får det nye børnesyn indflydelse på Frode og...

  5. Klar til barn : Kundskabsoversigt

    DEFF Research Database (Denmark)

    Ertmann, Bo; Guldager, Else; Nørgaard-Nielsen, Sofie

    forældrene er i fare for at reagere voldeligt over for deres børn. Et af de aspekter, der adskiller Klar til barn fra andre lignende projekter i Danmark, er, at forældrekursernes udformning og indhold er baseret på en grundig research af internationale erfaringer med forældreuddannelsestilbud. Konceptet blev...

  6. Mit barn er anbragt

    DEFF Research Database (Denmark)

    Nissen Møller, Sanne; Skytte Aalborg Universitet, Marianne

    Anbringelse af etniske minoritetsbørn og -unge udgør en voksende opgave for kommunerne. I denne bog belyses gennem 11 personlige livshistorier de særlige problemer og dilemmaer, som etniske minoritetsforældre står i, når deres barn anbringes. Livshistorierne giver et indblik i, hvordan forældrene...

  7. Barn med Asperger syndrom

    OpenAIRE

    Ahlström, Hanna

    2003-01-01

    Det här examensarbetet handlar om barn med Asperger syndrom. Syftet med arbetet var att ta reda på vad Asperger syndrom är och hur man som lärare kan hjälpa dessa elever på bästa sätt. Jag är intresserad av elever som har det svårt och antar att jag någon gång under min tid som lärare kommer att stöta på dessa elever. Arbetet inleds med en teorigenomgång där jag främst går igenom de utmärkande dragen hos barn med Asperger syndrom. Där går jag också bl a igenom orsaker till Asperger och diagn...

  8. Gebiedsbranding van de KennisAs Ede-Wageningen. Een praktijkgeoriënteerd ontwerponderzoek

    NARCIS (Netherlands)

    Taylor, Pier

    2017-01-01

    textabstractThis essay discusses the proposed design for informational objects for the place branding of the Food Innovation Strip Ede-Wageningen. The Food Innovation Strip Ede-Wageningen is the knowledge center of the FoodValley Region, one of the regions taking part in the top sectors policy, deve

  9. Root characteristics of selected field crops: data from the Wageningen Rhizolab (1990-2002)

    NARCIS (Netherlands)

    Smit, A.L.; Groenwold, J.

    2005-01-01

    Since being built in 1990, the rhizotron facility in Wageningen, the Wageningen Rhizolab, has been used for experiments on crops (e.g. Alfalfa, Brussels sprouts, common velvet grass, field bean, fodder radish, leeks, lupins, maize, potato, beetroot, ryegrass, spinach, spring wheat, winter rye and wi

  10. Gebiedsbranding van de KennisAs Ede-Wageningen. Een praktijkgeoriënteerd ontwerponderzoek

    NARCIS (Netherlands)

    Taylor, Pier

    2017-01-01

    textabstractThis essay discusses the proposed design for informational objects for the place branding of the Food Innovation Strip Ede-Wageningen. The Food Innovation Strip Ede-Wageningen is the knowledge center of the FoodValley Region, one of the regions taking part in the top sectors policy, deve

  11. Gebiedsbranding van de KennisAs Ede-Wageningen. Een praktijkgeoriënteerd ontwerponderzoek

    NARCIS (Netherlands)

    Taylor, Pier

    2017-01-01

    textabstractThis essay discusses the proposed design for informational objects for the place branding of the Food Innovation Strip Ede-Wageningen. The Food Innovation Strip Ede-Wageningen is the knowledge center of the FoodValley Region, one of the regions taking part in the top sectors policy,

  12. Bibliometric analyses on repository contents for the evaluation of research at Wageningen UR

    NARCIS (Netherlands)

    Veller, van M.G.P.; Gerritsma, W.; Togt, van der P.L.; Leon, C.D.; Zeist, van C.M.

    2010-01-01

    Since the last two decennia, Wageningen UR Library has been involved in bibliometric analyses for the evaluation of scientific output of staff, chair groups and research institutes of Wageningen UR. In these advanced bibliometric analyses several indicator scores, such as the number of publications,

  13. Gebiedsbranding van de KennisAs Ede-Wageningen. Een praktijkgeoriënteerd ontwerponderzoek

    NARCIS (Netherlands)

    Taylor, Pier

    2017-01-01

    abstractThis essay discusses the proposed design for informational objects for the place branding of the Food Innovation Strip Ede-Wageningen. The Food Innovation Strip Ede-Wageningen is the knowledge center of the FoodValley Region, one of the regions taking part in the top sectors policy, develope

  14. Application of user statistics and additional data for collection management of Wageningen UR digital library

    NARCIS (Netherlands)

    Veller, van M.G.P.; Spikman, G.

    2010-01-01

    Good collection management is necessary to guarantee the quality, quantity and costs of the online journal collection of Wageningen University and Research Centre (Wageningen UR) Digital Library. Via quantitative research on both subscription prices and usage statistics (i.e. download data from vend

  15. Kennis van Wageningen UR bestemd voor AOC-onderwijs: Lespakket attentie: gewasresistentie!

    NARCIS (Netherlands)

    Anonymous,

    2010-01-01

    Binnen de succesvolle samenwerking tussen het cursusonderwijs van de AOC’s en het agrarische onderzoek van Wageningen UR is een nieuw lespakket samengesteld ten behoeve van het dag- en cursusonderwijs gewasbescherming (licentie verlengingsbijeenkomsten). Het lespakket is samengesteld door onderzoeke

  16. Wageningse eerstejaars studenten 1975 [First-year students at the University of Wageningen 1975

    NARCIS (Netherlands)

    Mussen, G.; Zee, van der J.

    1979-01-01

    Motivation for study ( scientific interest, occupational perspective, general education ) / other studies considered / future direction of study / perceived features of university of Wageningen / preferred occupations after study / educational purpose of first year / occupational perspectives.

  17. From Extension Science to Communication and Innovation Studies. New Theoretical Trends from Wageningen.

    Science.gov (United States)

    Heymann, F. V.

    1998-01-01

    Wageningen University's extension science program shifted from a positivist to a constructivist foundation. Participatory methodologies and interactive policies are being developed, and the program's name has been changed to Communication and Innovation Studies. (SK)

  18. Ondernemer leert liefst buiten de klas : Wageningen Universiteit brengt competenties in beeld : special toekomst

    NARCIS (Netherlands)

    Bruinse, H.; Verstegen, J.A.A.M.; Lans, T.

    2009-01-01

    Wetenschappers van Wageningen Universiteit onderzochten de competenties van een groep ondernemers uit de glastuinbouw. Ze bekeken hierbij hoe de ondernemer in de praktijk leert, dus buiten regeliere studie om

  19. Wageningen UR Unmanned Aerial Remote Sensing Facility - Overview of activities

    Science.gov (United States)

    Bartholomeus, Harm; Keesstra, Saskia; Kooistra, Lammert; Suomalainen, Juha; Mucher, Sander; Kramer, Henk; Franke, Jappe

    2016-04-01

    To support environmental management there is an increasing need for timely, accurate and detailed information on our land. Unmanned Aerial Systems (UAS) are increasingly used to monitor agricultural crop development, habitat quality or urban heat efficiency. An important reason is that UAS technology is maturing quickly while the flexible capabilities of UAS fill a gap between satellite based and ground based geo-sensing systems. In 2012, different groups within Wageningen University and Research Centre have established an Unmanned Airborne Remote Sensing Facility. The objective of this facility is threefold: a) To develop innovation in the field of remote sensing science by providing a platform for dedicated and high-quality experiments; b) To support high quality UAS services by providing calibration facilities and disseminating processing procedures to the UAS user community; and c) To promote and test the use of UAS in a broad range of application fields like habitat monitoring, precision agriculture and land degradation assessment. The facility is hosted by the Laboratory of Geo-Information Science and Remote Sensing (GRS) and the Department of Soil Physics and Land Management (SLM) of Wageningen University together with the team Earth Informatics (EI) of Alterra. The added value of the Unmanned Aerial Remote Sensing Facility is that compared to for example satellite based remote sensing more dedicated science experiments can be prepared. This includes for example higher frequent observations in time (e.g., diurnal observations), observations of an object under different observation angles for characterization of BRDF and flexibility in use of camera's and sensors types. In this way, laboratory type of set ups can be tested in a field situation and effects of up-scaling can be tested. In the last years we developed and implemented different camera systems (e.g. a hyperspectral pushbroom system, and multispectral frame cameras) which we operated in projects all

  20. Two-dimensional screening of the Wageningen chicken BAC library.

    Science.gov (United States)

    Crooijmans, R P; Vrebalov, J; Dijkhof, R J; van der Poel, J J; Groenen, M A

    2000-05-01

    We have constructed a Bacterial Artificial Chromosome (BAC) library that provides 5.5-fold redundant coverage of the chicken genome. The library was made by cloning partial HindIII-digested high-molecular-weight (HMW) DNA of a female White Leghorn chicken into the HindIII site of the vector pECBAC1. Several modifications of standard protocols were necessary to clone efficiently large partial HindIII DNA fragments. The library consists of 49,920 clones arranged in 130 384-well plates. An average insert size of 134 kb was estimated from the analysis of 152 randomly selected BAC clones. The average number of NotI restriction sites per clone was 0.77. After individual growth, DNA was isolated of the pooled clones of each 384-well plate, and subsequently DNA of each plate was isolated from the individual row and column pools. Screening of the Wageningen chicken BAC library was performed by two-dimensional PCR with 125 microsatellite markers. For 124 markers at least one BAC clone was obtained. FISH experiments of 108 BAC clones revealed chimerism in less than 1%. The number of different BAC clones per marker present in the BAC library was examined for 35 markers which resulted in a total of 167 different BAC clones. Per marker the number of BAC clones varied from 1 to 11, with an average of 4.77. The chicken BAC library constitutes an invaluable tool for positional cloning and for comparative mapping studies.

  1. Kansen voor vrouwelijk talent : over carrières en barrières van vrouwen bij Wageningen UR

    NARCIS (Netherlands)

    Lebbink, S.; Steuten, C.; Neefjes, M.

    2013-01-01

    Dit rapport inventariseert de situatie van de doorstroming van vrouwelijke wetenschappers aan Wageningen UR. Zo blijkt er binnen Wageningen University een dik glazen plafond te bestaan, te meten aan de doorstroom van de ene functieschaal naar de volgende. In dit rapport beschrijven we een aantal oor

  2. Gebiedsbranding van de KennisAs Ede-Wageningen. Een praktijkgeoriënteerd ontwerponderzoek

    OpenAIRE

    Taylor, Pier

    2017-01-01

    textabstractThis essay discusses the proposed design for informational objects for the place branding of the Food Innovation Strip Ede-Wageningen. The Food Innovation Strip Ede-Wageningen is the knowledge center of the FoodValley Region, one of the regions taking part in the top sectors policy, developed in 2011 by the Dutch government. The branding aims to convincingly convey that this region holds many companies, organizations and knowledge institutes working together towards sustainable in...

  3. Rodenticides in British barn owls.

    Science.gov (United States)

    Newton, I; Wyllie, I; Freestone, P

    1990-01-01

    Out of 145 Barn Owls found dead through accidents (66%), starvation (32%), shooting (2%) and poisoning (Owls for successive periods of 1, 3 and 6 days. All six owls fed on difenacoum-dosed mice survived all three treatments, in which up to an estimated 101.7 microg of difenacoum was consumed, and the coagulation times of their blood returned to near normal in less than 5-23 days. Four of the six owls fed on brodifacoum-dosed mice died 6-17 days after the 1-day treatment, but the survivors also survived the 3-day and 6-day treatments. Those that died had each eaten 3 mice, with a combined weight of about 105g and a total brodifacoum content of about 46.07 microg, which was equivalent to a dose of 0.150-0.182 mg kg(-1) of owl body weight. After death these owls had 0.63-1.25 micro g(-1) of brodifacoum in their livers. Blood from the survivors would not coagulate at 9 days post-treatment, but did so at 16 days in one bird and between 38 and 78 days in the other. It is concluded that: (1) Barn Owls in Britain are now widely exposed to second-generation rodenticides; (2) not all owls exposed to these chemicals are likely to receive a lethal dose; (3) brodifacoum is more toxic to owls than difenacoum; and (4) while there is yet no evidence that rodenticides have had any appreciable effect on Barn Owl populations in Britain, further monitoring of residue levels and population trends in desirable.

  4. Til forsvar for barns spontane lek

    Directory of Open Access Journals (Sweden)

    Einar Sundsdal

    2015-04-01

    Full Text Available Barndommens far, Jean-Jacques Rousseau (1712-1778, og senere, barnehagens grunnlegger, Friedrich Frøbel (1782-1852, var begge opptatt av barndom og barns mulighet til å tape tid. Dette ble betegnet som negativ pedagogikk og innebar blant annet at barn skulle fordrive tiden med det som passet for barn: lek. Barna skulle få holde på for seg selv, voksne skulle ikke bedrive undervisning, men la barn oppdage verden selv. Disse tankene har vært sentrale for vår moderne forestilling om barndom, og de har vært premissgivende for Barnekonvensjonen som slår fast at alle barn har rett til å leke. Også i dag har leken en sentral posisjon når vi snakker om barndom, men nå knyttes den til en forestilling om å vinne tid. Barn blir nå skjøvet fremover slik at de ikke skal kaste bort tiden - tape tiden - men utnytte den mest mulig effektivt med tanke på et fremtidig resultat. Denne logikken har bidratt til at FN i 2013 gikk ut og advarte om at barns rett til lek er truet. I denne artikkelen vil vi forfølge FNs forsvar for barns spontane lek. Vi vil gjøre dette blant annet ved å vise at lekens egenverdi står stadig sterkere innen en rekke forskningstradisjoner.

  5. Ontwikkelingen in de functiekwaliteit van vrouwelijke en mannelijke afgestudeerden van de Landbouwuniversiteit Wageningen

    NARCIS (Netherlands)

    Bos - Boers, M.

    1992-01-01

    This study reports on research into the causes of disparities in the quality of employment between female and male graduates of the Wageningen Agricultural University (WAU).

    The data were collected by the Career Centre of the Alumni Association (NILI-MPW), in a continuing research

  6. Ontwikkelingen in de functiekwaliteit van vrouwelijke en mannelijke afgestudeerden van de Landbouwuniversiteit Wageningen.

    NARCIS (Netherlands)

    Bos-Boers, M.

    1992-01-01

    This study reports on research into the causes of disparities in the quality of employment between female and male graduates of the Wageningen Agricultural University (WAU).The data were collected by the Career Centre of the Alumni Association (NILI-MPW), in a continuing research project conducted s

  7. Samenwerkingsproject van RIVM, TNO en Wageningen Universiteit / Gezondheidseffecten van groenten en fruit

    NARCIS (Netherlands)

    Hendriks, H.; Verhagen, H.; Büchner, F.; Duijnhoven, van F.J.B.; Witkamp, R.F.; Peppelenbos, H.; Woltering, E.J.

    2010-01-01

    In 2007 publiceerden Wageningen-UR, TNO en RIVM samen met ZonMW het rapport 'Wat gaan we eten?' Een van de aanbevelingen was om tot meer samenhang en afstemming in het onderzoek te komen. Sindsdien stemmen de drie kennisinstituten hun activiteiten voor de ministeries van VWS en LNV op elkaar af. Het

  8. Early senescence of rice and Drechslera oryzae in the Wageningen polder, Surinam

    NARCIS (Netherlands)

    Klomp, A.O.

    1977-01-01

    Rice is grown in monoculture in the Wageningen Polder, Surinam, South America, which comprises 10 000 ha of heavy clay soil. Fungal diseases caused appreciable losses of the rice crop in several years. Drechslera oryzae van Breda de Haan was found to be the major pathogen of rice. Its most conspicuo

  9. Implementing portal functionality at Wageningen UR Library : combining the old with the new

    NARCIS (Netherlands)

    Loman, M.E.; Gerritsma, W.

    2003-01-01

    Library Wageningen UR is a relatively small, but highly specialized academic library serving a population of about 5900 researchers and 4700 students in the life sciences. To better serve the needs of our users portal functionality has been introduced gradually to our Desktop Library. A beginning wa

  10. Wageningen University and Research centre : Your partner for sustainable development in the Arctic

    NARCIS (Netherlands)

    Bolman, B.C.; Koomen, A.J.; Valeeva, N.I.; Karman, C.C.

    2011-01-01

    This position paper explores new claims in the Arctic region. These claims are closely connected to new developments in the region such as climate change and the utilisation of natural resources. The aim of the paper is to illustrate how Wageningen University and Research centre contributes to susta

  11. The development of a research data policy at Wageningen University & Research: best practices as a framework

    NARCIS (Netherlands)

    Zeeland, van Hilde; Ringersma, J.

    2017-01-01

    The current case study describes the development of a Research Data Management policy at Wageningen University & Research, the Netherlands. To develop this policy, an analysis was carried out of existing frameworks and principles on data management (such as the FAIR principles), as well as of

  12. Innledningsartikkel til temanummer om Barn og rom

    Directory of Open Access Journals (Sweden)

    Ellen Beate Sandseter

    2015-07-01

    Full Text Available I lys av utviklingen av barnehagens posisjon i det norske samfunnet og debatten om effekter av barnehagens fysiske miljø og organisering, dannet en gruppe tverrfaglige og tverrinstitusjonelle barnehageforskere i 2004 forskningsnettverket Barn og Rom. Nettverkets mål har vært å "skape ny og forskningsbasert kunnskap om det fysiske miljøets betydning for barn, og samtidig være et forum for kunnskapsdeling, utvikling av felles forskningsprosjekter, formidling og publisering, samt internasjonalt samarbeid med andre aktører og forskningsgrupper". Forskningsnettverket opererer med en definisjon av "Barn og Rom" som i vid forstand omfatter hele det fysiske miljøet barn vokser opp i. Dette inkluderer ulike landskap, for eksempel byen og naturen, steder, bygninger, ute- og innerom, innredning, møbler, utstyr, installasjoner og lekeapparater. Likevel har nettverket hatt et særlig fokus på barnehagens fysiske miljø og dets betydning for barn, personalet og den pedagogiske virksomheten og hvordan miljøet forstås, organiseres, skapes og endres av personalet og barn i barnehagen. Dette temanummeret er et resultat av noen av nettverksmedlemmenes arbeid de siste årene og presenterer en stor bredde både i metodisk tilnærming så vel som tematisk tilnærming til temaet "Barn og rom".

  13. Reactor

    Science.gov (United States)

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  14. Behandlas barn olika? : Smärtskattning på barn efter skoliosoperation

    OpenAIRE

    Karlsson, Linda; Zetterlund, Martin

    2010-01-01

    Inledning: Postoperativ smärta hos barn är fortfarande ett problem trots förbättrade arbetsrutiner och smärtbehandling. Smärtskattning på barn och speciellt barn med kognitiva nedsättningar kräver att sjuksköterskorna har kunskap om tillgängliga smärtskattningsinstrument. På så vis ges alla barn möjlighet att smärtskattas. Syfte: Att undersöka hur ofta sjuksköterskor smärtskattar barn som opereras för skolios postoperativt. Design: En retrospektiv studie. Metod: Journalgranskningen genomförde...

  15. Aggressiv periodontitt hos barn og unge

    OpenAIRE

    Pham, Hong Tram Thi

    2006-01-01

    1999 International Classification Workshop (1) innførte begrepet aggressiv periodontitt (AgP) i det nye klassifikasjonssystemet for periodontitt. AgP inkluderer gruppene tidligere klassifisert som: Prepubertal periodontitt Juvenil periodontitt Raskt progredierende periodontitt Vår oppgave omhandler AgP hos barn og unge. Ifølge WHO’s definisjon, er barn personer mellom 0-18 år. Vi har derfor tatt for oss de 2 første av de 3 gruppene under definisjonen AgP, tidligere kalt...

  16. Methods to study everyday use of products in households: The Wageningen Mouthing Study as an example.

    Science.gov (United States)

    Steenbekkers, L P

    2001-04-01

    Several methods exist to study human behaviour in everyday life: e.g. an oral or written interview, measurement of physical variables and observation. All of them have their advantages and disadvantages, which are described in this paper. When a clear picture of actual human behaviour and information about an entire activity are required, for example to assess risks of exposure to chemical substances, it is best to use a combination of available methods. In this way the advantages of all methods can be combined. This was done in the Wageningen mouthing study of which some results are presented.

  17. The landscape of Wageningen as an inspiring teaching environment for future environmental scientists

    Science.gov (United States)

    Keesstra, Saskia; Sonneveld, Marthijn

    2013-04-01

    Practical field work is an essential component in training future soil scientists. This is facilitated when a wide variety of geological materials geomorphological phenomena and soil patterns are within reach. One of the leading universities in soil science in the Netherlands, Wageningen University, was founded some hundred years ago in the small city of Wageningen because of the rich variety of soils and landscapes in its vicinity. Being located in the central part of the Netherlands, its region is famous because here Late-Pleistocene and Late-Holocene deposits meet. Wageningen is located on the slope of an ice pushed ridge which dates from the Saalien ice age, bordering a glacial tongue basin The ridge is mainly composed of pushed coarse grained fluvial deposits. In the Weichselien ice age cover sands have been deposited on the sides of this ridge. During the Holocene the ridge was eroded on the southern side, where the river Rhine has cut into the older deposits and deposited mainly fine grained fluvial deposits. Peat formation took place in the lower parts of the basin. In addition this region has been inhabited by people, who have worked, and fertilized the soil, creating a thickened A-horizon in some locations around Wageningen. This geological setting has created a palette of different sedimentary deposits which serve as mother material for a variety of soil types like podzols, brown forest soils, , fluvial clay to loamy soils, plaggen soils and peat soils. In our education we frequently use the soils in the surrounding as a teaching environment for our students. They are send out to use all their senses and look, feel, hear and sometimes even taste the soils. They use these impressions to describe the soils and understand why the soils are on that specific place in the landscape where we find it. We feel students benefit from this playground in our backyard, because, even though students work more and more in an individual and virtual environment where they

  18. Overview of Uav Activities in Wageningen Unmanned Aerial Remote Sensing Facility

    Science.gov (United States)

    Suomalainen, J.; Anders, N.; Franke, J.; Bartholomeus, H.; Nolet, C.; van Puijenbroek, M.; Kramer, H.; Keesstra, S.; Mücher, S.; Kooistra, L.

    2015-08-01

    The WUR Unmanned Aerial Remote Sensing Facility (UARSF) (www.wageningenur.nl/uarsf) is a co-operation organization of different groups within Wageningen University and Research Centre to use UAVs in remote sensing applications. The facility was founded in 2012. Since then the facility has taken part in numerous of mapping campaigns exploiting UAVs with researchers with in WUR as well as external cooperating partners. In this paper/poster we present the facility, the UAV platforms, the camera systems, and demonstrate some highlights of our results.

  19. October 2008 monitoring results for Barnes, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2009-02-26

    The Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) operated a grain storage facility at Barnes, Kansas, during most of the interval 1949-1974. Carbon tetrachloride contamination was initially detected in 1986 in the town's public water supply wells. In 2006-2007, the CCC/USDA conducted a comprehensive targeted investigation at and near its former property in Barnes to characterize this contamination. Those results were reported previously (Argonne 2008a). In November 2007, the CCC/USDA began quarterly groundwater monitoring at Barnes. The monitoring is being conducted on behalf of the CCC/USDA by Argonne National Laboratory, in accord with the recommendations made in the report for the 2006-2007 targeted investigation (Argonne 2008a). The objective is to monitor the carbon tetrachloride contamination identified in the groundwater at Barnes. The sampling is presently conducted in a network of 28 individual monitoring wells (at 19 distinct locations), 2 public water supply wells, and 1 private well (Figure 1.1). The results of the 2006-2007 targeted investigation and the subsequent monitoring events in November 2007 (Argonne 2008b), March 2008 (Argonne 2008c), and July 2008 (Argonne 2008d) demonstrated the presence of carbon tetrachloride contamination in groundwater at levels exceeding the Kansas Department of Health and Environment (KDHE) Tier 2 risk-based screening level (RBSL) of 5.0 {micro}g/L for this compound. The contaminant plume appears to extend from the former CCC/USDA property northwestward, toward the Barnes public water supply wells. Information obtained during the 2006-2007 investigations indicates that at least one other potential source might have contributed to the groundwater contaminant plume (Argonne 2008a). The former agriculture building owned by the local school district, located immediately east of well PWS3, is also a potential source of the contamination. This current report presents the results of the

  20. Development of a journal recommendation tool based upon co-citation analysis of journals cited in Wageningen UR research articles

    NARCIS (Netherlands)

    Veller, van M.G.P.; Gerritsma, W.

    2015-01-01

    Wageningen UR Library has developed a tool based upon co-citation analysis to recommend alternative journals to researchers for a journal they look up in the tool. The journal recommendations can be tuned in such a way to include citation preferences for each of the five science groups that comprise

  1. How Wageningen University and Research Center managed to influence researchers publishing behaviour towards more quality, impact and visibility

    NARCIS (Netherlands)

    Fondermann, Philipp; Togt, van der P.L.

    2016-01-01

    Wageningen University and Research Center (WUR) is one of the most prestigious research institutions in the world in life sciences and improved significantly in several rankings over the last years. One of the `drivers` of this success story is a comprehensive quality management exercise based on Re

  2. Wageningen Urban Rainfall Experiment 2014 (WURex14): Experimental setup and preliminary results

    Science.gov (United States)

    van Leth, Thomas C.; Uijlenhoet, Remko; Overeem, Aart; Leijnse, Hidde; Hazenberg, Pieter; Berne, Alexis

    2016-04-01

    Microwave links from cellular communication networks have been shown to be able to provide valuable information concerning the space-time variability of rainfall. In particular over urban areas, where network densities are generally high, they have the potential to complement existing dedicated infrastructure to measure rainfall (gauges, radars). In addition, microwave links provide a great opportunity for ground-based rainfall measurement for those land surface areas of the world where gauges and radars are generally lacking. Such information is not only crucial for water management and agriculture, but also for instance for ground validation of space-borne rainfall estimates such as those provided by the GPM (Global Precipitation Measurement) mission. WURex14 is dedicated to address several errors and uncertainties associated with such quantitative precipitation estimates in detail. The core of the experiment is provided by three co-located microwave links installed between two major buildings on the Wageningen University campus, approximately 2 km apart: a 38 GHz commercial microwave link, provided by T-Mobile NL, and 26 GHz and 38 GHz (dual-polarization) research microwave links from RAL. Transmitting and receiving antennas have been attached to masts installed on the roofs of the two buildings, about 30 m above the ground. This setup has been complemented with a Scintec infrared Large-Aperture Scintillometer, installed over the same path, as well as 5 Parsivel optical disdrometers and an automated rain gauge positioned at several locations along the path. Temporal sampling of the received signals was performed at a rate of 20 Hz. The setup is being monitored by time-lapse cameras to assess the state of the antennas as well as the atmosphere. Finally, data is available from the KNMI weather radars and an automated weather station situated just outside Wageningen. The experiment has been active between August 2014 and December 2015. We give a global overview of

  3. Barn og unge i det nye medielandskapet

    OpenAIRE

    Basmadjian, Elias

    2014-01-01

    Denne masteroppgaven tar for seg hvordan den digitale utviklingen fører til utfordringer i samfunnet. Gjennom å drøfte begrepet mediedanning tar den for seg hvordan denne utviklingen fører til at dagens barn og unge som blir født inn og vokser opp i et samfunn som er grunnleggende annerledes enn for bare noen år siden. Ettersom tilgangen på digitale nyvinninger og sosiale medier er «allestedsnærværende» stiller dette også krav til deres evne til å forstå og bruke denne teknologien på en bærek...

  4. A survey of Italian compost dairy barns

    Directory of Open Access Journals (Sweden)

    Lorenzo Leso

    2013-12-01

    Full Text Available Compost-bedded pack barns (CBPB, generally known as compost dairy barns, are alternative housing systems for dairy cows. In these barns, the whole surface of the resting area is covered with a deepbedded pack that is frequently stirred in order to incorporate fresh manure into the pack and to enhance the evaporation of water. Experiences with CBPB for dairy cows are reported in literature from the US, Israel, the Netherlands and Austria. Potential advantages of these housing systems regard animal welfare and manure management. Since 2006, this housing system has been widely applied in Italy. However, there is still little scientific knowledge available about Italian CBPB. This study aims to describe the housing system, assess producers’ satisfaction and measure performance of dairy cows housed in CBPB. Ten commercial dairy farms in northern Italy were involved in the study. All pens in each farm were surveyed to determine the total available surface area, bedded area and pack depth. A questionnaire was submitted to each farm manager in order to investigate management practices, labour requirement, amount of bedding materials used and producers’ satisfaction. The temperature of the bedded pack was measured in summer and in winter. Data from the Italian Dairy Association were collected for each herd over a period of one year (from September 2011 to September 2012. In the barns involved in the study, the average total available area was 10.9 m2/cow and the average pack area was 6.7 m2/cow. The bedded pack was aerated 1.4 times per day.The most commonly used bedding material in these farms was dry sawdust. The consumption of bedding materials was 8.1 m3/cow per year. A tendency towards inverse correlation was found between the space per cow and the amount of bedding needed per cow (R2=0.395; P=0.051. Operations related to pack management required 4.1 hours of labour per cow per year. A direct relationship was found between the bedded area space

  5. Pulmonary effects of exposure to pig barn air

    Directory of Open Access Journals (Sweden)

    Singh Baljit

    2006-06-01

    Full Text Available Abstract Swine production has undergone rapid transformation from family owned operation to a large scale industrial enterprise. Since increasing number of pigs are reared on a large scale in confined buildings, some of the swine barn workers may be employed to work eight hours per day. Swine barn workers suffer from higher incidences of impaired air flow and lung inflammation, which is attributed to high intensity and interrupted exposures to pig barn air. The air in these barns contains gases, dust, microbes and endotoxin with endotoxin being the major suspect as the cause of lung dysfunction. This review attempts to describe the current state of knowledge of incidences and mechanisms of pulmonary dysfunction following exposure to the barn air.

  6. PhD-level education in Wageningen: the approach at graduate school Production Ecology and Resource Conservation

    Science.gov (United States)

    Temme, Arnaud; van de Vijver, Claudius; Jetten, Theo; Suselbeek, Lennart

    2016-04-01

    Wageningen University's PhD programme is organized by Graduate Schools that are defined based on topics. The C.T. de Wit Graduate School for Production Ecology and Resource Conservation (PE&RC) focussed on topics ranging from ecology and soil science to crop modelling. The Graduate School's offering of PhD courses comprises methodological courses, topical courses, skills courses and international on-site courses. All courses are characterized by a high degree of ownership by PhD candidates themselves. In many cases, candidates apply the skills that they learn on datasets from their own studies, during the course. This allows them to get hands-on experience while working towards their own results. The international on-site courses uniquely bring together Wageningen PhD candidates from a wide range of disciplines to jointly discuss and learn with local PhD candidates. Candidates also highly value the extensive attention for candidates' wellbeing during their time in Wageningen, for instance through PhD weekends.

  7. 22 Matt Barnes 再出发

    Institute of Scientific and Technical Information of China (English)

    Husky

    2008-01-01

    太阳队·前锋·201厘米·28岁上季成绩·6.7分·42.3%投篮·4.4篮板如果你是我们的忠实读者,就会发现巴恩斯(Matt Barnes)在过去13个月内已经第三度登上这个单元了。究竟,这位生涯单季平均得分从没超过10分的球员,有何值得我们一再报导的地方呢?

  8. Marknadsföring till barn : Etik och ansvar

    OpenAIRE

    Haire, Miranda

    2013-01-01

    Detta examensarbete handlar om marknadsföring till barn, samt etiken och ansvaret kring ämnet. Ansvaret ligger mestadels hos marknadsförarna och föräldrarna. Marknadsföring till barn bedöms strängare av juridiska bestämmelser än vanlig marknadsföring, eftersom att barn är mera mottagliga och inte har samma erfarenhet som vuxna. Syftet med detta examensarbete är att få fram allmänt om marknadsföring till barn, etiska frågeställningar, samhällsansvaret samt ansvaret hos marknadsförare, föräldra...

  9. The Wageningen Lowland Runoff Simulator (WALRUS: application to the Hupsel Brook catchment and Cabauw polder

    Directory of Open Access Journals (Sweden)

    C. C. Brauer

    2014-02-01

    Full Text Available The Wageningen Lowland Runoff Simulator (WALRUS is a new parametric (conceptual rainfall-runoff model which accounts explicitly for processes that are important in lowland areas, such as groundwater-unsaturated zone coupling, wetness-dependent flowroutes, groundwater–surface water feedbacks, and seepage and surface water supply (see companion paper by Brauer et al., 2014. Lowland catchments can be divided into slightly sloping, freely draining catchments and flat polders with controlled water levels. Here, we apply WALRUS to two contrasting Dutch catchments: the Hupsel Brook catchment and Cabauw polder. In both catchments, WALRUS performs well: Nash–Sutcliffe efficiencies obtained after calibration on one year of discharge observations are 0.87 for the Hupsel Brook catchment and 0.83 for the Cabauw polder, with values of 0.74 and 0.76 for validation. The model also performs well during floods and droughts and can forecast the effect of control operations. Through the dynamic division between quick and slow flowroutes controlled by a wetness index, temporal and spatial variability in groundwater depths can be accounted for, which results in adequate simulation of discharge peaks as well as low flows. The performance of WALRUS is most sensitive to the parameter controlling the wetness index and the groundwater reservoir constant, and to a lesser extent to the quickflow reservoir constant. The effects of these three parameters can be identified in the discharge time series, which indicates that the model is not overparameterised (parsimonious. Forcing uncertainty was found to have a larger effect on modelled discharge than parameter uncertainty and uncertainty in initial conditions.

  10. The Wageningen Lowland Runoff Simulator (WALRUS): application to the Hupsel Brook catchment and the Cabauw polder

    Science.gov (United States)

    Brauer, C. C.; Torfs, P. J. J. F.; Teuling, A. J.; Uijlenhoet, R.

    2014-10-01

    The Wageningen Lowland Runoff Simulator (WALRUS) is a new parametric (conceptual) rainfall-runoff model which accounts explicitly for processes that are important in lowland areas, such as groundwater-unsaturated zone coupling, wetness-dependent flowroutes, groundwater-surface water feedbacks, and seepage and surface water supply (see companion paper by Brauer et al., 2014). Lowland catchments can be divided into slightly sloping, freely draining catchments and flat polders with controlled water levels. Here, we apply WALRUS to two contrasting Dutch catchments: the Hupsel Brook catchment and the Cabauw polder. In both catchments, WALRUS performs well: Nash-Sutcliffe efficiencies obtained after calibration on 1 year of discharge observations are 0.87 for the Hupsel Brook catchment and 0.83 for the Cabauw polder, with values of 0.74 and 0.76 for validation. The model also performs well during floods and droughts and can forecast the effect of control operations. Through the dynamic division between quick and slow flowroutes controlled by a wetness index, temporal and spatial variability in groundwater depths can be accounted for, which results in adequate simulation of discharge peaks as well as low flows. The performance of WALRUS is most sensitive to the parameter controlling the wetness index and the groundwater reservoir constant, and to a lesser extent to the quickflow reservoir constant. The effects of these three parameters can be identified in the discharge time series, which indicates that the model is not overparameterised (parsimonious). Forcing uncertainty was found to have a larger effect on modelled discharge than parameter uncertainty and uncertainty in initial conditions.

  11. The Wageningen Lowland Runoff Simulator (WALRUS): application to the Hupsel Brook catchment and Cabauw polder

    Science.gov (United States)

    Brauer, C. C.; Torfs, P. J. J. F.; Teuling, A. J.; Uijlenhoet, R.

    2014-02-01

    The Wageningen Lowland Runoff Simulator (WALRUS) is a new parametric (conceptual) rainfall-runoff model which accounts explicitly for processes that are important in lowland areas, such as groundwater-unsaturated zone coupling, wetness-dependent flowroutes, groundwater-surface water feedbacks, and seepage and surface water supply (see companion paper by Brauer et al., 2014). Lowland catchments can be divided into slightly sloping, freely draining catchments and flat polders with controlled water levels. Here, we apply WALRUS to two contrasting Dutch catchments: the Hupsel Brook catchment and Cabauw polder. In both catchments, WALRUS performs well: Nash-Sutcliffe efficiencies obtained after calibration on one year of discharge observations are 0.87 for the Hupsel Brook catchment and 0.83 for the Cabauw polder, with values of 0.74 and 0.76 for validation. The model also performs well during floods and droughts and can forecast the effect of control operations. Through the dynamic division between quick and slow flowroutes controlled by a wetness index, temporal and spatial variability in groundwater depths can be accounted for, which results in adequate simulation of discharge peaks as well as low flows. The performance of WALRUS is most sensitive to the parameter controlling the wetness index and the groundwater reservoir constant, and to a lesser extent to the quickflow reservoir constant. The effects of these three parameters can be identified in the discharge time series, which indicates that the model is not overparameterised (parsimonious). Forcing uncertainty was found to have a larger effect on modelled discharge than parameter uncertainty and uncertainty in initial conditions.

  12. Efficient Evaluation of Massive Mellin--Barnes Integrals

    CERN Document Server

    Gluza, Janusz; Kosower, David A

    2016-01-01

    We show how to evaluate one-dimensional Minkowski-region Mellin-Barnes representations arising from massive loop integrals, by modifying the contours of integration. We implement an exact solution to the differential equation determining the contours of stationary phase. We also present several simple approximations to these contours. Our approach points the way to more efficient computations of massless and massive Mellin-Barnes integrals in both Euclidean and Minkowski regions.

  13. Delivery of Functionality in Complex Food Systems: Physically Inspired Approaches from Nanoscale to Microscale, Wageningen 18-21 October 2009.

    Science.gov (United States)

    van der Linden, Erik; Ubbink, Job; Duchateau, Guus

    2010-12-01

    The Wageningen Delivery of Functionality symposium covered all aspects involved with food structural design to arrive at high-quality foods which meet demanding customer expectations and regulatory requirements. The symposium integrated aspects from the structural organization of foods at molecular and supramolecular scales to dedicated techniques required to describe and visualize such structures, the gastro-intestinal events and how to model these in a laboratory setting, and finally the impact those food structures and ingredients have on the consumer's physiology and on the human perception. As an interdisciplinary platform, bringing together more than 160 researchers from academia and industry, the symposium meanwhile fulfills an important role in the food science community.

  14. Otoacoustic interrelationships of the barn owl

    Science.gov (United States)

    Bergevin, Christopher; Manley, Geoffrey A.; Köppl, Christine

    2015-12-01

    Significant debate still exists about the biophysical mechanisms at work in otoacoustic emission (OAE) generation and how such may differ between mammals and non-mammals given gross morphological differences (e.g., existence of basilar membrane traveling waves, degree of tectorial membrane coupling). To further elucidate general principles at work, we examined the barn owl for interrelationships between spontaneous emissions (SOAEs) and those evoked using a single tone (SFOAEs). First, most ears exhibited SOAEs as a stable periodic `rippling' whose peak-to-peak spacing was relatively constant (˜0.4 kHz). Some ears showed substantially larger narrowband peaks, although their statistical distributions were highly noisy. Second, significant interactions between a low-level tone and SOAE activity were observed via an interference pattern as the tone frequency was swept. Using a suppression paradigm to extract SFOAEs as the residual, the magnitude exhibited a stable pattern of peaks and valleys unique to each ear. Third, SFOAE phase exhibited significant accumulation as frequency was swept, with a phase-gradient delay of approximately 2 ms that was constant across frequency. The amount of SFOAE phase accumulation between adjacent SOAE peaks tended to cluster about an integral number of cycles, as previously observed for humans. Taken together, our data suggest that the principles underlying how active hair cells work together (e.g., entrainment, phase coherence) are shared between widely different inner ear morphologies, leading to the generation of OAEs with similar properties.

  15. Wageningen Urban Rainfall Experiment 2014 (WURex14): Experimental Setup and First Results

    Science.gov (United States)

    van Leth, Thomas; Uijlenhoet, Remko; Overeem, Aart; Leijnse, Hidde; Hazenberg, Pieter

    2015-04-01

    Microwave links from cellular communication networks have been shown to be able to provide valuable information concerning the space-time variability of rainfall. In particular over urban areas, where network densities are generally high, they have the potential to complement existing dedicated infrastructure to measure rainfall (gauges, radars). In addition, microwave links provide a great opportunity for ground-based rainfall measurement for those land surface areas of the world where gauges and radars are generally lacking, e.g. Africa, Latin America, and large parts of Asia. Such information is not only crucial for water management and agriculture, but also for instance for ground validation of space-borne rainfall estimates such as those provided by the recently launched core satellite of the GPM (Global Precipitation Measurement) mission. WURex14 is dedicated to address several errors and uncertainties associated with such quantitative precipitation estimates in detail. The core of the experiment is provided by two co-located microwave links installed between two major buildings on the Wageningen University campus, approximately 2 km apart: a 38 GHz commercial microwave link, kindly provided to us by T-Mobile NL, and a 38 GHz dual-polarization research microwave link from RAL. Transmitting and receiving antennas have been attached to masts installed on the roofs of the two buildings, about 30 m above the ground. This setup has been complemented with a Scintec infrared Large-Aperture Scintillometer, installed over the same path, as well as a Parsivel optical disdrometer, located close to the mast on the receiving end of the links. During the course of the experiment, a 26 GHz RAL research microwave link was added to the experimental setup. Temporal sampling of the received signals was performed at a rate of 20 Hz. In addition, two time-lapse cameras have been installed on either side of the path to monitor the wetness of the antennas as well as the state of

  16. Adaptation potential of naturally ventilated barns to high temperature extremes: The OptiBarn project

    Science.gov (United States)

    Menz, Christoph

    2016-04-01

    Climate change interferes with various aspects of the socio-economic system. One important aspect is its influence on animal husbandry, especially dairy faming. Dairy cows are usually kept in naturally ventilated barns (NVBs) which are particular vulnerable to extreme events due to their low adaptation capabilities. An effective adaptation to high outdoor temperatures for example, is only possible under certain wind and humidity conditions. High temperature extremes are expected to increase in number and strength under climate change. To assess the impact of this change on NVBs and dairy cows also the changes in wind and humidity needs to be considered. Hence we need to consider the multivariate structure of future temperature extremes. The OptiBarn project aims to develop sustainable adaptation strategies for dairy housings under climate change for Europe, by considering the multivariate structure of high temperature extremes. In a first step we identify various multivariate high temperature extremes for three core regions in Europe. With respect to dairy cows in NVBs we will focus on the wind and humidity field during high temperature events. In a second step we will use the CORDEX-EUR-11 ensemble to evaluate the capability of the RCMs to model such events and assess their future change potential. By transferring the outdoor conditions to indoor climate and animal wellbeing the results of this assessment can be used to develop technical, architectural and animal specific adaptation strategies for high temperature extremes.

  17. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  18. Spontaneous otoacoustic emissions in the barn owl.

    Science.gov (United States)

    Taschenberger, G; Manley, G A

    1997-08-01

    Spontaneous otoacoustic emissions (SOAE) were studied in a bird, the barn owl. They were found in 79% of the ears investigated, and each emitting ear generated on average 1.9 emissions. Their peak sound-pressure levels lay between -5.8 and 10.3 dB, and their centre frequencies between 2.3 and 10.5 kHz. The SOAE originated primarily in the upper quarter of the animal's hearing range, and derived from a specialized area previously described as being within an auditory fovea. Indeed, 93% of the emissions had centre frequencies above 7.5 kHz. The median of the frequency distances between neighbouring SOAE was 406 Hz (0.058 oct). The 3 dB bandwidth of the emissions depended on their amplitude above the noise: for SOAE whose level exceeded 10 dB above the noise floor, the 3 dB bandwidths ranged between 4.5 and 11.4 Hz. SOAE frequencies were temperature sensitive. Raising the temperature shifted the emissions to higher frequencies, and vice versa (the frequency shifted on average 0.039 oct/degrees C). External tones could suppress the level of SOAE, an effect that was highly tuned. For SOAE with frequencies between 2.5 and 10.5 kHz, the Q(10dB) values of 2 dB iso-suppression tuning curves (STC) varied from 1.07 to 10.40. The best thresholds of 2 dB STC were generally below 15 dB SPL.

  19. MBsums. A Mathematica package for the representation of Mellin-Barnes integrals by multiple sums

    Energy Technology Data Exchange (ETDEWEB)

    Ochman, Michal; Riemann, Tord

    2015-11-15

    Feynman integrals may be represented by the Mathematica package AMBRE and MB as multiple Mellin-Barnes integrals. With the Mathematica package MBsums we transform these Mellin-Barnes integrals into multiple sums.

  20. REDESIGN OF COMMONLY USED TOBACCO CURING BARNS IN ZIMBABWE FOR INCREASED ENERGY EFFICIENCY

    Directory of Open Access Journals (Sweden)

    SPECIAL MUSONI

    2013-03-01

    Full Text Available In Zimbabwe two types of barns are commonly used for tobacco curing, namely the traditional and Rocket barns. The traditional barn and the Rocket Barn loose 98.5% and 55.6% of the energy supplied respectively. The latter is 43.6% more thermally efficient than the traditional barn. There is, however, potential of increasing the energy efficiency of both barns. In this study, a design that incorporates structural changes to reduce heat loss as well as recovery of heat was developed. The design is a combination of commercially available components, and allows for ventilation heat re-use and increased heat transfer from furnace ducts to the drying chamber. The structure was found to be 54.7% more thermally efficient than the Rocket barn and 74.2% more efficient than the traditional barn. The new design needs to be field-tested so that it can be adopted by tobacco farmers.

  1. Barns psykosociala hälsa i skolmiljö

    OpenAIRE

    Nysand, Maria; Hannus, Martina; Jaakkola, Riina

    2010-01-01

    Vårt examensarbete ingår i ett delprojekt i KLUCK2 och syftar till att undersöka skolan som fysisk och psykosocial miljö. Ämnesområdet för examensarbetet är barns psyko-sociala hälsa i relation till mobbning, stress och trivsel i skolmiljö. Syftet med vår studie är att undersöka vad som uppmärksammas i ny forskning kring barns psykosociala hälsa och vilka faktorer som framkallar psykosocial ohälsa eller hälsa hos barn i skolan. Detta examensarbete genomförs som en litteraturstudie. Under...

  2. Design and Implementation of a Task/Resource Information System. Reported by the Planning Department of the Agricultural University of Wageningen.

    Science.gov (United States)

    van Bladeren, D.; And Others

    The University of Wageningen takes care of only one faculty with 80 departments and about 4000 students. The university has been growing rapidly in recent years with an increase of 25 percent in first year students each year. Because of this growth and because of various social developments, the University Board recognizes the need for a good data…

  3. Design and Implementation of a Task/Resource Information System. Reported by the Planning Department of the Agricultural University of Wageningen.

    Science.gov (United States)

    van Bladeren, D.; And Others

    The University of Wageningen takes care of only one faculty with 80 departments and about 4000 students. The university has been growing rapidly in recent years with an increase of 25 percent in first year students each year. Because of this growth and because of various social developments, the University Board recognizes the need for a good data…

  4. Design methodology for the robotic milking barn : modelling, simulation, validation and optimization

    NARCIS (Netherlands)

    Halachmi, I.

    1999-01-01

    The traditional barn design is a milking parlour oriented. To integrate a milking robot the barn should be redesigned according to the robotic milking concept. The entire system (barn design, feeding and cow-traffic routines, management practices) should encourage 'voluntary milking', i.e., it shoul

  5. Design methodology for the robotic milking barn : modelling, simulation, validation and optimization

    NARCIS (Netherlands)

    Halachmi, I.

    1999-01-01

    The traditional barn design is a milking parlour oriented. To integrate a milking robot the barn should be redesigned according to the robotic milking concept. The entire system (barn design, feeding and cow-traffic routines, management practices) should encourage 'voluntary milking', i.e.,

  6. The Wageningen Lowland Runoff Simulator (WALRUS): a lumped rainfall-runoff model for catchments with shallow groundwater

    Science.gov (United States)

    Brauer, C. C.; Teuling, A. J.; Torfs, P. J. J. F.; Uijlenhoet, R.

    2014-10-01

    We present the Wageningen Lowland Runoff Simulator (WALRUS), a novel rainfall-runoff model to fill the gap between complex, spatially distributed models which are often used in lowland catchments and simple, parametric (conceptual) models which have mostly been developed for sloping catchments. WALRUS explicitly accounts for processes that are important in lowland areas, notably (1) groundwater-unsaturated zone coupling, (2) wetness-dependent flow routes, (3) groundwater-surface water feedbacks and (4) seepage and surface water supply. WALRUS consists of a coupled groundwater-vadose zone reservoir, a quickflow reservoir and a surface water reservoir. WALRUS is suitable for operational use because it is computationally efficient and numerically stable (achieved with a flexible time step approach). In the open source model code default relations have been implemented, leaving only four parameters which require calibration. For research purposes, these defaults can easily be changed. Numerical experiments show that the implemented feedbacks have the desired effect on the system variables.

  7. Evaluating multiloop Feynman integrals by Mellin-Barnes representation

    CERN Document Server

    Smirnov, V A

    2004-01-01

    The status of analytical evaluation of double and triple box diagrams is characterized. The method of Mellin-Barnes representation as a tool to evaluate master integrals in these problems is advocated. New MB representations for massive on-shell double boxes with general powers of propagators are presented.

  8. Bedded pack barns for dairy cattle in the Netherlands

    NARCIS (Netherlands)

    Galama, P.J.; Boer, de H.C.; Dooren, van H.J.C.; Ouweltjes, W.; Poelarends, J.J.; Driehuis, F.

    2014-01-01

    The bedded pack barn offers good perspective on animal welfare, animal health and public perception, but has disadvantages in terms of mineral management (nitrogen losses and fertilising value) and the presence of TAS (Thermophilic Aerobic Spore formers). Bedded packs with compost have a too high am

  9. Barn music at St Donat's castle / Philip Gross

    Index Scriptorium Estoniae

    Gross, Philip, 1952-

    2011-01-01

    Muusikafestivalist "Vale of Glamorgan", mis oli 2010. a. pühendatud Arvo Pärdile. Eesti kammermuusikaansambli Resonabilis kavas oli ka festivali tellimusel valminud uelsi helilooja Gareth Peredur Churchilli "Vocable", mille teksti kirjutas Philip Gross. Festivalikontsertide muljeid leiab Grossi luuletsüklis "Barn music" (avaldatud samas ajakirjanumbris, lk. 42-43)

  10. Spatial and Nonspatial Escape Strategies in the Barnes Maze

    Science.gov (United States)

    Harrison, Fiona E.; Reiserer, Randall S.; Tomarken, Andrew J.; McDonald, Michael P.

    2006-01-01

    The Barnes maze is a spatial memory task that requires subjects to learn the position of a hole that can be used to escape the brightly lit, open surface of the maze. Two experiments assessed the relative importance of spatial (extra-maze) versus proximal visible cues in solving the maze. In Experiment 1, four groups of mice were trained either…

  11. Disinfection effectiveness of slightly acidic electrolysed water in swine barns.

    Science.gov (United States)

    Hao, X X; Li, B M; Zhang, Q; Lin, B Zh; Ge, L P; Wang, C Y; Cao, W

    2013-09-01

    To evaluate the disinfection effectiveness of slightly acidic electrolysed water (SAEW, pH 6·25-6·53), a new environmental friendly agent for inactivating micro-organisms adhered to the facility and aerosolized in the air of the swine barns and to explore the application of SAEW in livestock industries. Bacteria and fungi were isolated from the swine house air and treated by SAEW. The SAEW solution was flushed onto surfaces and sprayed within the whole swine barn. SAEW with an available chlorine concentration (ACC) of 300 mg l(-1) can inhibit isolated microbes completely. The usage of SAEW (300 mg l(-1) ) resulted in a significant (P reduced 59% of the airborne organisms in 30 min and kept the population of microbes at a reduced level for at least 8 h. SAEW treatment also reduced pathogens on surfaces (P reduce infections in swine barns. The results of this study provide information on the antimicrobial efficiency of SAEW on the airborne bacteria and fungi in swine barns. © 2013 The Society for Applied Microbiology.

  12. Barn music at St Donat's castle / Philip Gross

    Index Scriptorium Estoniae

    Gross, Philip, 1952-

    2011-01-01

    Muusikafestivalist "Vale of Glamorgan", mis oli 2010. a. pühendatud Arvo Pärdile. Eesti kammermuusikaansambli Resonabilis kavas oli ka festivali tellimusel valminud uelsi helilooja Gareth Peredur Churchilli "Vocable", mille teksti kirjutas Philip Gross. Festivalikontsertide muljeid leiab Grossi luuletsüklis "Barn music" (avaldatud samas ajakirjanumbris, lk. 42-43)

  13. John Dewey's Socially Instrumental Practice at the Barnes Foundation and the Role of "Transferred Values" in Aesthetic Experience

    Science.gov (United States)

    Johnson, Margaret Hess

    2012-01-01

    When Albert Barnes established an art education program at the Barnes Foundation in 1924, he asked John Dewey to become the first president and director of education. Barnes and Dewey enjoyed a sustained and fruitful relationship with regard to aesthetic experience and scientific theory as applied to education. Barnes and Dewey shared a serious…

  14. Aeroallergens in dairy barns near Cooperstown, New York and Rochester, Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, A.R.; Swanson, M.C.; Fernandez-Caldas, E.; Reed, C.E.; May, J.J.; Pratt, D.S. (Mayo Medical School, Rochester, MN (USA))

    1989-08-01

    We sampled atmospheric barn air using a volumetric air sampler in ten barns near Cooperstown, NY and six barns near Rochester, MN, and, with radioimmunoassays, measured allergens of Aspergillus fumigatus, Thermoactinomyces vulgaris, Micropolyspori faeni, short ragweed, rye grass group I pollen, Alternaria (Alt-1), Dermatophagoides sp. Lepidoglyphus destructor, common insect allergen, mouse urine, rat urine, and cattle epithelium. The most abundant allergen present was A. fumigatus followed by L. destructor. This study provides initial data on barn aerobiology and demonstrates for the first time the abundance of L. destructor allergens in North American dairy barns. More comprehensive study of barns, poultry houses, confinement houses for swine, and other agricultural environments from various geographic locations is needed to define the allergen levels to which millions of farm workers are exposed each day. While most of the allergens were expected, the presence of airborne allergens reactive with antisera to Dermatophagoides suggests indirectly that substantial amounts of pyroglyphid mites are present in some barns.

  15. Drinking and Cleaning Water Use in a Dairy Cow Barn

    Directory of Open Access Journals (Sweden)

    Michael Krauß

    2016-07-01

    Full Text Available Water is used in dairy farming for producing feed, watering the animals, and cleaning and disinfecting barns and equipment. The objective of this study was to investigate the drinking and cleaning water use in a dairy cow barn. The water use was measured on a well-managed commercial dairy farm in North-East Germany. Thirty-eight water meters were installed in a barn with 176 cows and two milking systems (an automatic milking system and a herringbone parlour. Their counts were logged hourly over 806 days. On average, the cows in the automatic milking system used 91.1 (SD 14.3 L drinking water per cow per day, while those in the herringbone parlour used 54.4 (SD 5.3 L per cow per day. The cows drink most of the water during the hours of (natural and artificial light in the barn. Previously published regression functions of drinking water intake of the cows were reviewed and a new regression function based on the ambient temperature and the milk yield was developed (drinking water intake (L per cow per day = −27.937 + 0.49 × mean temperature + 3.15 × milk yield (R2 = 0.67. The cleaning water demand had a mean of 28.6 (SD 14.8 L per cow per day in the automatic milking system, and a mean of 33.8 (SD 14.1 L per cow per day in the herringbone parlour. These findings show that the total technical water use in the barn makes only a minor contribution to water use in dairy farming compared with the water use for feed production.

  16. Barnes maze testing strategies with small and large rodent models.

    Science.gov (United States)

    Rosenfeld, Cheryl S; Ferguson, Sherry A

    2014-02-26

    Spatial learning and memory of laboratory rodents is often assessed via navigational ability in mazes, most popular of which are the water and dry-land (Barnes) mazes. Improved performance over sessions or trials is thought to reflect learning and memory of the escape cage/platform location. Considered less stressful than water mazes, the Barnes maze is a relatively simple design of a circular platform top with several holes equally spaced around the perimeter edge. All but one of the holes are false-bottomed or blind-ending, while one leads to an escape cage. Mildly aversive stimuli (e.g. bright overhead lights) provide motivation to locate the escape cage. Latency to locate the escape cage can be measured during the session; however, additional endpoints typically require video recording. From those video recordings, use of automated tracking software can generate a variety of endpoints that are similar to those produced in water mazes (e.g. distance traveled, velocity/speed, time spent in the correct quadrant, time spent moving/resting, and confirmation of latency). Type of search strategy (i.e. random, serial, or direct) can be categorized as well. Barnes maze construction and testing methodologies can differ for small rodents, such as mice, and large rodents, such as rats. For example, while extra-maze cues are effective for rats, smaller wild rodents may require intra-maze cues with a visual barrier around the maze. Appropriate stimuli must be identified which motivate the rodent to locate the escape cage. Both Barnes and water mazes can be time consuming as 4-7 test trials are typically required to detect improved learning and memory performance (e.g. shorter latencies or path lengths to locate the escape platform or cage) and/or differences between experimental groups. Even so, the Barnes maze is a widely employed behavioral assessment measuring spatial navigational abilities and their potential disruption by genetic, neurobehavioral manipulations, or drug

  17. Elevated frequency of abnormalities in barn swallows from Chernobyl.

    Science.gov (United States)

    Møller, A P; Mousseau, T A; de Lope, F; Saino, N

    2007-08-22

    Ever since the Chernobyl accident in 1986, that contaminated vast areas in surrounding countries with radiation, abnormalities and birth defects have been reported in human populations. Recently, several studies suggested that the elevated frequency of such abnormalities can be attributed to poverty and stress in affected human populations. Here, we present long-term results for a free-living population of barn swallows, Hirundo rustica, demonstrating the presence of 11 morphological abnormalities in populations around Chernobyl, but much less frequently in an uncontaminated Ukrainian control population and three more distant control populations. The presence of these abnormalities in barn swallows is associated with reduced viability. These findings demonstrate a link between morphological abnormalities and radiation in an animal population that cannot be attributed to poverty and stress. The most parsimonious hypothesis for abnormalities in animal and human populations alike is that the effects are caused by the same underlying cause, viz. radiation derived from the Chernobyl accident.

  18. Morphometry of auricular feathers of barn owls (Tyto alba).

    Science.gov (United States)

    Koch, U R; Wagner, H

    2002-02-01

    In all owl species, the facial plumage forms a parabolic dish, the facial ruff, which is most conspicuous in the the barn owl (Tyto alba). The center of the ruff is formed by auricular feathers. Such feathers are also found on the preaural flaps which cover the ear openings, and in the region of the beak. In this study, we compare the different types of auricular feathers of the barn owl with contour feathers from the neck. Auricular feathers are characterised by an open vane structure and fewer barbs as compared to contour feathers. Auricular feathers also have fewer distal and proximal barbules than contour feathers. The open vane of the auricular feather results from an acute angle between the barb and the basis of the barbules, and from the extension of the pennula parallel to the barbs. These reductions are differently expressed in the three different types of auricular feathers investigated here and correspond with their function (protecting the ruff from dust).

  19. Det raske og det syge nyfødte barn

    DEFF Research Database (Denmark)

    Peitersen, Birgit; Pedersen, Pernille; Pryds, Ole

    NEONATOLOGI er en lære- og håndbog om det raske og det syge nyfødte barn. Den henvender sig især til sundhedspersonale, der arbejder med nyfødte børn – herunder sygeplejersker, jordemødre og medicinske kandidater. I de første kapitler gennemgås almene emner som fosterets udvikling, muligheder...

  20. Mellin-Barnes Representation of the Topological String

    CERN Document Server

    Krefl, Daniel

    2015-01-01

    We invoke integrals of Mellin-Barnes type to analytically continue the Gopakumar-Vafa resummation of the topological string free energy in the string coupling constant, leading to additional non-perturbative terms. We also discuss in a similar manner the refined and Nekrasov-Shatashvili limit version thereof. The derivation is straight-forward and essentially boils down to taking residue. This allows us to confirm some related conjectures in the literature at tree-level.

  1. Annual Report of Monitoring at Barnes, Kansas, in 2012

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, Lorraine M. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-06-01

    Barnes, Kansas, is a small rural community (population approximately 150) located in Washington County, in north-central Kansas (Figure 1.1). Barnes is located in Section 9, Township 4 South, Range 5 East, at approximate latitude 39°43'0'' north and longitude 96°52'25'' west (USGS 1968). The city lies in a transition zone between the Flint Hills and the glaciated region. The area’s topography consists of gently sloping hills of Pleistocene loess (< 20 ft) overlying a shale unit and interbedded shale, limestone, and siltstone of the Permian Chase Group. Groundwater for the public water supply is obtained from wells PWS2 and PWS3 at reported depths of 155 ft and 160 ft, respectively, located in the northwestern portion of the city. The water is produced from the bedrock aquifer of the Chase Group. Section 2 summarizes the hydrogeologic conceptual site model. This report summarizes findings for groundwater inspection in Barnes.

  2. Temperature distribution of air source heat pump barn with different air flow

    Science.gov (United States)

    He, X.; Li, J. C.; Zhao, G. Q.

    2016-08-01

    There are two type of airflow form in tobacco barn, one is air rising, the other is air falling. They are different in the structure layout and working principle, which affect the tobacco barn in the distribution of temperature field and velocity distribution. In order to compare the temperature and air distribution of the two, thereby obtain a tobacco barn whose temperature field and velocity distribution are more uniform. Taking the air source heat pump tobacco barn as the investigated subject and establishing relevant mathematical model, the thermodynamics of the two type of curing barn was analysed and compared based on Fluent. Provide a reasonable evidence for chamber arrangement and selection of outlet for air source heat pump tobacco barn.

  3. EMDR-behandling  : Barns och ungdomars upplevelser en kvalitetssäkringsstudie 

    OpenAIRE

    Fredin, Ingela

    2005-01-01

    Föreliggande studie är dels ett led i att kvalitetssäkra EMDR (Eye Movement Desensitization and Reprocessing) som behandlingsmetod för barn och ungdomar och dels att utröna om behandlingen bidragit till ett förbättrat mående. EMDR som behandlingsmetod för barn och ungdomar har stöd i kontrollerade studier, men ytterligare forskning behövs. I den här studien deltog åtta barn och ungdomar med varierande diagnoser, vilka fått EMDR-behandling i barn- och ungdomspsykiatrisk öppenvård. Behandlingen...

  4. Compost bedded pack dairy barn management, performance, and producer satisfaction.

    Science.gov (United States)

    Black, R A; Taraba, J L; Day, G B; Damasceno, F A; Bewley, J M

    2013-01-01

    The objective of the research was to characterize herd performance, producer satisfaction and recommendations, and management practices used by compost bedded pack (CBP) managers in Kentucky (42 farms and 47 CBP facilities). Farms were visited between October 2010 and March 2011. A random selection of cows housed solely in the CBP were scored for locomotion and hygiene. Changes in monthly Dairy Herd Improvement Association performance records, including milk production, SCC, reproductive performance, and daily bulk-tank somatic cell count after moving into the CBP were analyzed using the MIXED procedure of SAS (SAS 9.3; SAS Institute Inc., Cary, NC). The GLM procedure of SAS (SAS 9.3) was used to develop models to describe CBP moisture, CBP temperature at 20.3 cm, and mean herd hygiene. Producers provided 9.0 ± 2.2 m2 of pack space per cow (n = 44). Barns constructed with an attached feed alley cost $1,051 ± 407 per cow (n = 40). Barns constructed without an attached feed alley cost $493 ± 196 per cow (n = 13). Kiln-dried shavings required 0.05 ± 0.04 m3 of bedding per cow per day (n = 15). Green shavings required 0.07 ± 0.06 m3 of bedding per cow per day (n = 12). The most-frequently cited benefits of the CBP included cow comfort (n = 28), cow cleanliness (n = 14), and the low-maintenance nature of the system (n = 10). Increased stirring frequency, stirring depth, and ambient temperature increased pack temperature, measured at 20.3 cm below the CBP surface. Increased stirring depth, pasture-adjusted space per cow, and drying rate decreased CBP moisture. Mean herd locomotion and hygiene scores were 1.5 ± 0.3 (n = 34) and 2.2 ± 0.4 (n = 34), respectively. Increased 20.3-cm depth CBP temperature and ambient temperatures improved mean herd hygiene. Bulk-tank somatic cell count decreased from the year before to the year after moving into the CBP barn (323,692 ± 7,301 vs. 252,859 ± 7,112 cells/mL, respectively) for farms using the CBP barn as the primary

  5. H Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The H Reactor was the first reactor to be built at Hanford after World War II.It became operational in October of 1949, and represented the fourth nuclear reactor on...

  6. The Wageningen Lowland Runoff Simulator (WALRUS): implementation and application to the freely draining Hupsel Brook catchment and controlled Cabauw polder

    Science.gov (United States)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2014-05-01

    Recently, we developed the Wageningen Lowland Runoff Simulator (WALRUS) to fill the gap between complex, spatially distributed models which are often used in lowland catchments and simple, parametric models which have mostly been developed for mountainous catchments. This parametric rainfall-runoff model can be used all over the world in both freely draining lowland catchments and polders with controlled water levels. Here, we present the model implementation, opportunities for practical application and experience from validation studies with data from two field sites. The open source model code is implemented in R and is set-up such that it can be used by both practitioners and researchers. For direct use by practitioners, defaults are implemented for relations between model variables and to compute initial conditions, leaving only four parameters which require calibration. For research purposes, the defaults can easily be changed. WALRUS is computationally efficient, which allows operational forecasting and uncertainty estimation by creating ensembles. An approach for flexible time steps increases numerical stability and makes model parameter values independent of time step size, which facilitates use of the model with the same parameter set for multi-year water balance studies as well as detailed analyses of individual flood peaks. We applied WALRUS to two contrasting Dutch catchments: the slightly sloping, freely draining Hupsel Brook catchment and the flat Cabauw polder with controlled water levels. In both catchments, WALRUS performs well during the years used for calibration and validation. The model also performs well during extremely wet periods (flash flood in the Hupsel Brook catchment in August 2010) and extremely dry periods (summer 1976) and can forecast the effect of control operations (changing weir elevations and surface water supply).

  7. Designing the optimal robotic milking barn by applying a queuing network approach

    NARCIS (Netherlands)

    Halachmi, I.; Adan, I.J.B.F.; Wald, van der J.; Beek, van P.; Heesterbeek, J.A.P.

    2003-01-01

    The design of various conventional dairy barns is based on centuries of experience, but there is hardly any experience with robotic milking barns (RMB). Furthermore, as each farmer has his own management practices, the optimal layout is `site dependent¿. A new universally applicable design methodolo

  8. Designing the optimal robotic milking barn, Part 1: Quantifying facility usage

    NARCIS (Netherlands)

    Halachmi, I.; Metz, J.H.M.; Maltz, E.; Dijkhuizen, A.A.; Speelman, L.

    2000-01-01

    The aim of this paper is to explore the stochastic nature of the usage of facilities in a robotic milking barn, independent of the barn layout. It presents experimental data obtained by monitoring 10 dairy cows over a period of 18 days. To minimize restrictions to the access of cows to the facilitie

  9. Unheralded Historian: Mary Sheldon Barnes and Primary Source Material in History Books

    Science.gov (United States)

    Chisholm, James A., Jr.

    2013-01-01

    In the latter part of the nineteenth century, Mary Sheldon Barnes emerged as a leading historical methods professor and history textbook author. Although men dominated the field, she wrote several articles and books alone or with her husband Earl Barnes about primary source materials and teaching. She lived during an era in United States history…

  10. Designing the optimal robotic milking barn, part 2: behaviour-based simulation

    NARCIS (Netherlands)

    Halachmi, I.

    2000-01-01

    Robotic milking affects factors that determine the barn layout, such as cow behaviour, farm routine, feeding procedure and management practices. As there is hardly any experience with robotic barns, and each farmer has his own management attitude, depending on his personality and local conditions; t

  11. Barnes Ice Cap South Dome Trilateration Net Survey Data 1970-1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Barnes Ice Cap data set contains survey measurements of a network of 43 stakes along a 10 km flow line on the northeast flank of the south dome of the Barnes Ice...

  12. Social interactions of dairy cows introduced postpartally to a separated barn section - pilot study

    DEFF Research Database (Denmark)

    Burow, Elke; Nielsen, Tine Rousing; Halekoh, Ulrich

    2009-01-01

    The hypothesis of reduced social activity of early lactating dairy cows when transferred postpartally to a separated barn section (S, group size 9.3 SD 2.1) vs. to a barn section of the main lactating herd (H, group size 130.1 SD 57.9) was tested. Social interactions of 12 cows in S and 14 cows i...

  13. Barns kommunikasjon med ulike typer kart - en progressiv tilnærming til kartlesing

    Directory of Open Access Journals (Sweden)

    Trine Bjerva

    2011-11-01

    Full Text Available Utgangspunktet for denne studien er en erkjennelse av hvor vanskelig det kan være for barn å samhandle med det symbolske kartet. Hovedmålet for prosjektet var å utvikle sikrere viten om hvordan barn kommuniserer med ulike typer kart. Det er utarbeidet en modell (Bjerva, Græsli, & Sigurjónsson, 2010 som viser hvordan vi kan utvikle ferdigheten kartlesing hos barn. Vi har undersøkt 106 barn i alderen 3 til 12 år om hvordan de mestrer direkte representasjoner (detaljfoto og perspektiv representasjoner (håndtegnet skråkart. Forskningsdesignet har en økologisk tilnærming hvor datainnsamlingen har foregått i terrenget. Resultatene indikerer at selv små barn mestrer antatt kompliserte oppgaver når de blir presentert for enkle hjelpemidler.

  14. New four-dimensional integrals by Mellin-Barnes transform

    CERN Document Server

    Allendes, Pedro; Kondrashuk, Igor; Cuello, Eduardo A Notte

    2009-01-01

    This paper is devoted to the calculation by Mellin-Barnes transform of a especial class of integrals. It contains double integrals in the position space in d = 4-2e dimensions, where e is parameter of dimensional regularization. These integrals contribute to the effective action of the N = 4 supersymmetric Yang-Mills theory. The integrand is a fraction in which the numerator is a logarithm of ratio of spacetime intervals, and the denominator is the product of powers of spacetime intervals. According to the method developed in the previous papers, in order to make use of the uniqueness technique for one of two integrations, we shift exponents in powers in the denominator of integrands by some multiples of e. As the next step, the second integration in the position space is done by Mellin-Barnes transform. For normalizing procedure, we reproduce first the known result obtained earlier by Gegenbauer polynomial technique. Then, we make another shift of exponents in powers in the denominator to create the logarith...

  15. Annual report of monitoring at Barnes, Kansas, in 2010.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M. (Environmental Science Division)

    2011-05-25

    The Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) operated a grain storage facility at Barnes, Kansas, in 1949-1974. Carbon tetrachloride contamination was initially detected in 1986 in the town's public water supply wells. In 2006-2007, the CCC/USDA conducted a comprehensive targeted investigation at and near its former property in Barnes to characterize this contamination. Those results were reported previously (Argonne 2008a). The results of that investigation indicated that carbon tetrachloride contamination is present in groundwater at low to moderate levels in the vicinity of the former CCC/USDA grain storage facility. Information obtained during the 2006-2007 investigation also indicated that at least one other potential source might have contributed to the groundwater contaminant plume (Argonne 2008a). The former agriculture building owned by the local school district, located immediately east of well PWS3, is also a potential source of the contamination. In November 2007, the CCC/USDA began periodic groundwater monitoring at Barnes. The monitoring is being conducted on behalf of the CCC/USDA by Argonne National Laboratory, under the direction of the Kansas Department of Health and Environment (KDHE). The objective is to monitor the carbon tetrachloride contamination identified in the groundwater at Barnes. Through 2010, sampling was conducted in a network of 28 individual monitoring wells (at 19 distinct locations), 2 public water supply wells, and 1 private well (Figure 1.1). The results of the 2006-2007 targeted investigation and the subsequent monitoring events (Argonne 2008a-d, 2009a,b, 2010) demonstrated the presence of carbon tetrachloride contamination in groundwater at levels exceeding the KDHE Tier 2 risk-based screening level (RBSL) of 5.0 {micro}g/L for this compound. The contaminant plume appears to extend from the former CCC/USDA property northwestward, toward the Barnes public water supply wells. Long

  16. The Wageningen Lowland Runoff Simulator (WALRUS): a Novel Open Source Rainfall-Runoff Model for Areas with Shallow Groundwater

    Science.gov (United States)

    Brauer, C.; Teuling, R.; Torfs, P.; Uijlenhoet, R.

    2014-12-01

    Recently, we developed the Wageningen Lowland Runoff Simulator (WALRUS) to fill the gap between complex, spatially distributed models which are often used in lowland regions and simple, parametric models which have mostly been developed for mountainous catchments. This parametric rainfall-runoff model can be used all over the world, both in freely draining lowland catchments and polders with controlled water levels. Here, we present the model implementation and our recent experience in training students and practitioners to use the model. WALRUS has several advantages that facilitate practical application. Firstly, WALRUS is computationally efficient, which allows for operational forecasting and uncertainty estimation by running ensembles. Secondly, the code is set-up such that it can be used by both practitioners and researchers. For direct use by practitioners, defaults are implemented for relations between model variables and for the computation of initial conditions based on discharge only, leaving only four parameters which require calibration. For research purposes, the defaults can easily be changed. Finally, an approach for flexible time steps increases numerical stability and makes model parameter values independent of time step size, which facilitates use of the model with the same parameter set for multi-year water balance studies as well as detailed analyses of individual flood peaks. The open source model code is currently implemented in R and compiled into a package. This package will be made available through the R CRAN server. A small massive open online course (MOOC) is being developed to give students, researchers and practitioners a step-by-step WALRUS-training. This course contains explanations about model elements and its advantages and limitations, as well as hands-on exercises to learn how to use WALRUS. All code, course, literature and examples will be collected on a dedicated website, which can be found via www

  17. The Wageningen Lowland Runoff Simulator (WALRUS): development of a novel parametric rainfall-runoff model using field experience

    Science.gov (United States)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2014-05-01

    We present the Wageningen Lowland Runoff Simulator (WALRUS), a novel rainfall-runoff model to fill the gap between complex, spatially distributed models for lowland catchments and simple, parametric models for mountainous catchments. From observations and experience from two Dutch field sites (the Hupsel Brook catchment and the Cabauw polder), we identified key processes for runoff generation in lowland catchments and important feedbacks between components in the hydrological system. We used this knowledge to design a parametric model which can be used all over the world in both freely draining lowland catchments and polders with controlled water levels. While using only four parameters which require calibration, WALRUS explicitly accounts for processes that are important in lowland areas: (1) Groundwater-unsaturated zone coupling: WALRUS contains one soil reservoir, which is divided effectively by the (dynamic) groundwater table into a groundwater zone and a vadose zone. The condition of this soil reservoir is described by two strongly dependent variables: the groundwater depth and the storage deficit (the effective thickness of empty pores). This implementation enables capillary rise when the top soil has dried through evapotranspiration. (2) Wetness-dependent flowroutes: The storage deficit determines the division of rain water between the soil reservoir (slow routes: infiltration, percolation and groundwater flow) and a quickflow reservoir (quick routes: drainpipe, macropore and overland flow). (3) Groundwater-surface water feedbacks: Surface water forms an explicit part of the model structure. Drainage depends on the difference between surface water level and groundwater level (rather than groundwater level alone), allowing for feedbacks and infiltration of surface water into the soil. (4) Seepage and surface water supply: Groundwater seepage and surface water supply or extraction (pumping) are added to or subtracted from the soil or surface water reservoir

  18. Barns Society as a Buffer Stock (Case in Nglaris Village Bener District Purworejo Regency)

    Science.gov (United States)

    Riptanti, E. W.; Qonita, A.; Suprapti

    2017-04-01

    Nglaris village is a mountainous area with most of its agricultural lands are used for growing annual crops, while only small agricultural areas are for growing rice. However, the post-harvest storage, in the form of barn society, can supply the people’s needs of rice. Article describes the function of barn society as a buffer for foods supply. Research design was exploratory research, aims to generate in-depth qualitative and contextual data. The technique applied in this research was a case study. The cost for barn society maintenance was collected from the joint venture between farmers united in the barn society group. The barn society has 20 tons capacity for unhulled rice. The farmers obtained the income from working during the harvest time and become a labour harvester to outside Nglaris or called “boro”. The farmer (field owner) gave natura wages (“bawon”). Bawon calculated based on the result of total harvested unhulled. Supply for buffer of foods in the dry season was at least 50% of the capacity barn society’s, so that it can secure the supplies of staple foods. The barn society is specifically advantageous during the dry season because each farmer could lend and should be returned within one year.

  19. Long-Term Evaluation of the Scintec Boundary-Layer Scintillometer and the Wageningen Large-Aperture Scintillometer: Implications for Scintillometer Users

    Science.gov (United States)

    Van Kesteren, B.; Beyrich, F.; Hartogensis, O. K.; Braam, M.

    2015-08-01

    We compare the structure parameter of the refractive index, , measured simultaneously with two large-aperture scintillometers: the WagLAS (Wageningen University, Wageningen, the Netherlands) and the BLS900 (Scintec, Rottenburg, Germany). A 3.5-year dataset shows a bias in of about 17 % between the instruments. Analysis of these data reveals firstly that the logarithmic amplifiers in the WagLAS exhibit a strong dependence on temperature, resulting in an overestimation of of up to 35 % for temperatures 0 . Secondly, high-pass filtering of the WagLAS and BLS900 intensity data artificially reduces for crosswinds 2 (error 25 and 5 % respectively). Thirdly, the BLS900 increasingly underestimates (up to 10-15 %) with increasing signal saturation. We demonstrate that Scintec's data processing relies too heavily on the assumption that the intensity data obey a log-normal distribution, which they do not in the case of saturation. Fourthly, both instruments ignore the dissipation range of the refractive-index spectrum, which leads to an overestimation of of up to 30 % for friction velocity 0.2 . Implications of these findings are discussed and placed into perspective for other scintillometer users. Furthermore, we present a tool for revealing saturation and other violations of Rytov theory for any given scintillometer type, including microwave scintillometers.

  20. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  1. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    1962-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  2. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  3. Improvement of directionality and sound-localization by internal ear coupling in barn owls

    DEFF Research Database (Denmark)

    Wagner, Hermann; Christensen-Dalsgaard, Jakob; Kettler, Lutz

    Mark Konishi was one of the first to quantify sound-localization capabilities in barn owls. He showed that frequencies between 3 and 10 kHz underlie precise sound localization in these birds, and that they derive spatial information from processing interaural time and interaural level differences....... However, despite intensive research during the last 40 years it is still unclear whether and how internal ear coupling contributes to sound localization in the barn owl. Here we investigated ear directionality in anesthetized birds with the help of laser vibrometry. Care was taken that anesthesia...... time difference in the low-frequency range, barn owls hesitate to approach prey or turn their heads when only low-frequency auditory information is present in a stimulus they receive. Thus, the barn-owl's sound localization system seems to be adapted to work best in frequency ranges where interaural...

  4. Et juridisk perspektiv på overgangen fra barn til voksen

    DEFF Research Database (Denmark)

    Dalmar, Pernille Lykke

    2014-01-01

    Med udgangspunkt i en case om en udsat ung, belyser kapitlet lovgivningens betydning for overgangen fra barn til voksen. Kapitlet belyser den juridiske pligt til at klare sig selv, når man fylder 18 år...

  5. Chicken barn climate and hazardous volatile compounds control using simple linear regression and PID

    Science.gov (United States)

    Abdullah, A. H.; Bakar, M. A. A.; Shukor, S. A. A.; Saad, F. S. A.; Kamis, M. S.; Mustafa, M. H.; Khalid, N. S.

    2016-07-01

    The hazardous volatile compounds from chicken manure in chicken barn are potentially to be a health threat to the farm animals and workers. Ammonia (NH3) and hydrogen sulphide (H2S) produced in chicken barn are influenced by climate changes. The Electronic Nose (e-nose) is used for the barn's air, temperature and humidity data sampling. Simple Linear Regression is used to identify the correlation between temperature-humidity, humidity-ammonia and ammonia-hydrogen sulphide. MATLAB Simulink software was used for the sample data analysis using PID controller. Results shows that the performance of PID controller using the Ziegler-Nichols technique can improve the system controller to control climate in chicken barn.

  6. Reliable low-cost devices for monitoring ammonia concentrations and emissions in naturally ventilated dairy barns.

    Science.gov (United States)

    Wang, Xiang; Ndegwa, Pius M; Joo, HungSoo; Neerackal, George M; Harrison, Joseph H; Stöckle, Claudio O; Liu, Heping

    2016-01-01

    This research investigated the use of two relatively cost-effective devices for determining NH3 concentrations in naturally ventilated (NV) dairy barns including an Ogawa passive sampler (Ogawa) and a passive flux sampler (PFS). These samplers were deployed adjacent to sampling ports of a photoacoustic infrared multigas spectroscope (INNOVA), in a NV dairy barn. A 3-day deployment period was deemed suitable for both passive samplers. The correlations between concentrations determined with the passive samplers and the INNOVA were statistically significant (r = 0.93 for Ogawa and 0.88 for PFS). Compared with reference measurements, Ogawa overestimated NH3 concentrations in the barn by ∼ 14%, while PFS underestimated NH3 concentrations by ∼ 41%. Barn NH3 emission factors per animal unit (20.6-21.2 g d(-1) AU(-1)) based on the two passive samplers, after calibration, were similar to those obtained with the reference method and were within the range of values reported in literature.

  7. Analysis of Temperature and Humidity Field in a New Bulk Tobacco Curing Barn Based on CFD

    Science.gov (United States)

    Bai, Zhipeng; Guo, Duoduo; Li, Shoucang; Hu, Yaohua

    2017-01-01

    A new structure bulk tobacco curing barn was presented. To study the temperature and humidity field in the new structure tobacco curing barn, a 3D transient computational fluid dynamics (CFD) model was developed using porous medium, species transport, κ-ε turbulence and discrete phase models. The CFD results demonstrated that (1) the temperature and relative humidity predictions were validated by the experimental results, and comparison of simulation results with experimental data showed a fairly close agreement; (2) the temperature of the bottom and inlet area was higher than the top and outlet area, and water vapor concentrated on the top and outlet area in the barn; (3) tobacco loading density and thickness of tobacco leaves had an explicit effect on the temperature distributions in the barn. PMID:28146128

  8. Reactor Neutrinos

    OpenAIRE

    Soo-Bong Kim; Thierry Lasserre; Yifang Wang

    2013-01-01

    We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very ...

  9. BOILING REACTORS

    Science.gov (United States)

    Untermyer, S.

    1962-04-10

    A boiling reactor having a reactivity which is reduced by an increase in the volume of vaporized coolant therein is described. In this system unvaporized liquid coolant is extracted from the reactor, heat is extracted therefrom, and it is returned to the reactor as sub-cooled liquid coolant. This reduces a portion of the coolant which includes vaporized coolant within the core assembly thereby enhancing the power output of the assembly and rendering the reactor substantially self-regulating. (AEC)

  10. Condition, Reproduction and Survival of Barn Swallows from Chernobyl

    National Research Council Canada - National Science Library

    A. P. Møller; T. A. Mousseau; G. Milinevsky; A. Peklo; E. Pysanets; T. Szép

    2005-01-01

    1. We investigated the relationship between radiation arising from the fall-out due to the explosion of the nuclear reactor at Chernobyl, Ukraine, and body condition, rate of reproduction and survival...

  11. Membrane reactor. Membrane reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shindo, Y.; Wakabayashi, K. (National Chemical Laboratory for Industry, Tsukuba (Japan))

    1990-08-05

    Many reaction examples were introduced of membrane reactor, to be on the point of forming a new region in the field of chemical technology. It is a reactor to exhibit excellent function, by its being installed with membrane therein, and is generally classified into catalyst function type and reaction promotion type. What firstly belongs to the former is stabilized zirconia, where oxygen, supplied to the cathodic side of membrane with voltage, impressed thereon, becomes O {sup 2 {minus}} to be diffused through the membrane and supplied, as variously activated oxygenous species, on the anodic side. Examples with many advantages can be given such as methane coupling, propylene oxidation, methanating reaction of carbon dioxide, etc. Apart, palladium film and naphion film also belong to the former. While examples of the latter comprise, among others, decomposition of hydrogen sulfide by porous glass film and dehydrogenation of cyclohexane or palladium alloy film, which are expected to be developed and materialized in the industry. 33 refs., 8 figs.

  12. Female barn owls (Tyto alba) advertise good genes.

    Science.gov (United States)

    Roulin, A; Jungi, T W; Pfister, H; Dijkstra, C

    2000-05-07

    The good genes hypothesis of sexual selection postulates that ornamentation signals superior genetic quality to potential mates. Support for this hypothesis comes from studies on male ornamentation only, while it remains to be shown that female ornamentation may signal genetic quality as well. Female barn owls (Tyto alba) display more black spots on their plumage than males. The expression of this plumage trait has a genetic basis and it has been suggested that males prefer to mate with females displaying more black spots. Given the role of parasites in the evolution of sexually selected traits and of the immune system in parasite resistance, we hypothesize that the extent of female plumage 'spottiness' reflects immunological defence. We assessed the genetic variation in specific antibody production against a non-pathogenic antigen among cross-fostered nestlings and studied its covariation with the plumage spottiness of genetic parents. The magnitude of the antibody response was positively correlated with the plumage spottiness of the genetic mother but not of the genetic father. Our study thereby provides the first experimental support, to our knowledge, for the hypothesis that female ornamentation signals genetic quality.

  13. Rehabilitation of farmhouses and barns: limits of salt content

    Science.gov (United States)

    De Clercq, Hilde; Godts, Sebastiaan

    2016-09-01

    The rehabilitation of historic buildings is a practice that aims to turn a historic property into a state of contemporary comfort for private or commercial use, while preserving its historic, architectural and cultural value, respecting items of authenticity, compatibility and sustainability. What once was a modest use of locally fired brick and mortar has become the subject of ambitious rehabilitation campaigns conforming to the rules of comfort and hygiene of the twenty-first century. A pre-investigation concerning the diagnosis of damage phenomena and the risk assessment of interventions is a crucial aspect for the success of a restoration campaign. The question of "How to optimally preserve a monument within its current conditions" is replaced by "How can a monument optimally perform in the conditions suited to the assigned rehabilitation project". Today historic farms and their surroundings, after being abandoned for several decades, are the subject of different types of private or commercial rehabilitation projects. An example of such a project is the farm "Hof De Pleyne" in Loppem (West-Flanders, Belgium). The project intended to integrate a restaurant kitchen into the former animal barn. The limits of salt content with respect to the desired rehabilitation facilities while respecting safety regulations are presented.

  14. Analysis of thermal characteristics of electrical wiring for load groups in cattle barns.

    Science.gov (United States)

    Kim, Doo Hyun; Yoo, Sang-Ok; Kim, Sung Chul; Hwang, Dong Kyu

    2015-01-01

    The purpose of the current study is to analyze the thermal characteristics of electrical wirings depending on the number of operating load by connecting four types of electrical wirings that are selected by surveying the conditions for the electric fans, automatic waterers and halogen warm lamps that were installed in cattle barns in different years. The conditions of 64 cattle barns were surveyed and an experimental test was conducted at a cattle barn. The condition-survey covered inappropriate design, construction and misuse of electrical facility, including electrical wiring mostly used, and the mode of load current was evaluated. The survey showed that the mode of load current increased as the installation year of the fans, waterers and halogen lamps became older. Accordingly, the cattle barn manager needed to increase the capacity of the circuit breaker, which promoted the degradation of insulation of the electrical wires' sheath and increased possibility for electrical fires in the long-run. The test showed that the saturation temperature of the wire insulated sheath increased depending on the installation year of the load groups, in case of VCTFK and VFF electric wires, therefore, requiring their careful usage in the cattle barns.

  15. Directional hearing in the barn owl (Tyto alba).

    Science.gov (United States)

    Coles, R B; Guppy, A

    1988-05-01

    The acoustical properties of the external ear of the barn owl (Tyto alba) were studied by measuring sound pressure in the ear canal and outer ear cavity. Under normal conditions, pressure amplification by the external ear reaches about 20 dB between 3-9 kHz but decreases sharply above 10 kHz. The acoustic gain curve of the outer ear cavity alone is close to that of a finite-length exponential horn between 1.2-13 kHz with maximum gain reaching 20 dB between 5-9 kHz. Pressure gain by the facial ruff produces a maximum of 12 dB between 5-8 kHz and decreases rapidly above 9 kHz. The directional sensitivity of the external ear was obtained from pressure measurements in the ear canal. Directivity of the major lobe is explained, to a first approximation, by the sound diffraction properties of a circular aperture. Aperture size is based on the average radius (30 mm) of the open face of the ruff. Above 5 kHz, the external ear becomes highly directional and there is a 26 degree disparity in elevation between the acoustic axis of the left and right ear. In azimuth, directivity patterns are relocated closer to the midline as frequency increases and the acoustic axis moves at a rate of 20 degree/octave between 2-13 kHz. Movement of the axis can be explained, to a first approximation, by the acoustical diffraction properties of an obliquely truncated horn, due to the asymmetrical shape of the outer ear cavity. The directional sensitivity of the barn owl ear was studied by recording cochlear microphonic (CM) potentials from the round window membrane. Between 3-9 kHz, CM directivity patterns are clearly different to the directivity patterns of the external ear; CM directionality is abruptly lost above 10 kHz. Above 5 kHz, CM directivity patterns are characterized by an elongated major lobe containing the CM axis, forming a tilted band of high amplitude but low directionality (CM axial plane), closely bordered by minima or nulls. The highest directionality is found in the CM

  16. Characterization of Staphylococcus xylosus isolated from broiler chicken barn bioaerosol.

    Science.gov (United States)

    Vela, Javier; Hildebrandt, Kelsie; Metcalfe, Andrew; Rempel, Heidi; Bittman, Shabtai; Topp, Edward; Diarra, Moussa

    2012-12-01

    In this study we isolated and characterized Staphylococcus xylosus, a coagulase-negative staphylococcal species considered as commensal and one of the prevalent staphylococcal species found in poultry bioaerosol. Isolates were obtained using air samplers and selective phenylethyl alcohol agar for gram-positive bacteria during 35-d periods at different times of the day. A total of 200 colonies were recovered and after basic biochemical tests were performed, presumptive staphylococci were subsequently identified by API Staph strips. A total of 153 (76.5%) staphylococci were found, among which 84 were S. xylosus (46 and 38 isolated inside and outside, respectively). Biofilm formation was observed in 86.9% of S. xylosus isolates, whereas 79.8% of them showed hemolytic activity. There was a strong correlation (92.5%) between biofilm formation and hemolytic activity. All 84 S. xylosus isolates were susceptible to amikacin, ampicillin/sulbactam, chloramphenicol, ciprofloxacin, gentamycin, kanamycin, linezolid, trimethoprim/sulfamethoxazole, and vancomycin. Resistance to nalidixic acid (86.9%), novobiocin (85.7%), penicillin (70.2%), lincomycin (46.4%), oxacillin (42.9%), ampicillin (27.4%), tetracycline (21.4%), erythromycin (11.9%), bacitracin (10.7%), and streptomycin (2.4%) was observed among the isolates. Resistance to tetracycline, lincomycin, erythromycin, and β-lactam antibiotics was occasionally linked to the tetK, linA, ermB, and blaZ genes, respectively. Random amplification of polymorphic DNA results showed similarity of 15 to 99% between isolates collected outside and inside the barn, indicating genetic diversity of these isolates. Our study indicates that characterization of poultry bioaerosol coagulase-negative staphylococcal species such as S. xylosus is necessary for assessing their safety status for both poultry and humans.

  17. Memory Revisited in Julian Barnes's The Sense of an Ending

    Directory of Open Access Journals (Sweden)

    Maricel Oró Piqueras

    2014-02-01

    Full Text Available An accumulation of years brings with it an accumulation of experiences. The revision of such experiences usually becomes more recurrent after retirement, a transition time from one period of life to another and, as such, a time in which we, human beings, have a tendency to take stock of our lives. This is actually one of the main issues present in Julian Barnes's last novel The Sense of an Ending (2011. When the main protagonist, a retired man quite comfortable and contented with his present life, receives an unexpected inheritance from the mother of a girlfriend from his university years, he is forced to track down a part of his life that he had left at the back of his mind a long time ago. As he explains his story, the protagonist and narrator of the novel raises a number of questions related to the quality and function of memory as one gets into old age. He experiments the unreliability of memory and questions to what extent memory is constructed through the remembered emotions that invaded him over that episode of his life rather than through the events as they actually took place. On the other hand, the act of revisiting and revising that specific episode, brings with it feelings of guilt and remorse as the protagonist realises that his past acts were not as noble as he remembered them to be. However, these acts are part of the past and they cannot be changed; thus, another question that the novel raises is how to account for those actions of which one does not feel proud and, more importantly, how to manage those bad memories as one gets older

  18. Multifunctional reactors

    NARCIS (Netherlands)

    Westerterp, K.R.

    1992-01-01

    Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much

  19. Low frequency eardrum directionality in the barn owl induced by sound transmission through the interaural canal

    DEFF Research Database (Denmark)

    Kettler, Lutz; Christensen-Dalsgaard, Jakob; Larsen, Ole Næsbye

    2016-01-01

    The middle ears of birds are typically connected by interaural cavities that form a cranial canal. Eardrums coupled in this manner may function as pressure difference receivers rather than pressure receivers. Hereby, the eardrum vibrations become inherently directional. The barn owl also has...... a large interaural canal, but its role in barn owl hearing and specifically in sound localization has been controversial so far. We discuss here existing data and the role of the interaural canal in this species and add a new dataset obtained by laser Doppler vibrometry in a free-field setting....... Significant sound transmission across the interaural canal occurred at low frequencies. The sound transmission induces considerable eardrum directionality in a narrow band from 1.5 to 3.5 kHz. This is below the frequency range used by the barn owl for locating prey, but may conceivably be used for locating...

  20. Low frequency eardrum directionality in the barn owl induced by sound transmission through the interaural canal.

    Science.gov (United States)

    Kettler, Lutz; Christensen-Dalsgaard, Jakob; Larsen, Ole Næsbye; Wagner, Hermann

    2016-10-01

    The middle ears of birds are typically connected by interaural cavities that form a cranial canal. Eardrums coupled in this manner may function as pressure difference receivers rather than pressure receivers. Hereby, the eardrum vibrations become inherently directional. The barn owl also has a large interaural canal, but its role in barn owl hearing and specifically in sound localization has been controversial so far. We discuss here existing data and the role of the interaural canal in this species and add a new dataset obtained by laser Doppler vibrometry in a free-field setting. Significant sound transmission across the interaural canal occurred at low frequencies. The sound transmission induces considerable eardrum directionality in a narrow band from 1.5 to 3.5 kHz. This is below the frequency range used by the barn owl for locating prey, but may conceivably be used for locating conspecific callers.

  1. Performance and carcass characteristics of finishing beef cattle managed in a bedded hoop-barn system.

    Science.gov (United States)

    Honeyman, M S; Busby, W D; Lonergan, S M; Johnson, A K; Maxwell, D L; Harmon, J D; Shouse, S C

    2010-08-01

    The use of bedded hoop barns in finishing systems for beef cattle has not been widely researched. In this management system, beef cattle are confined to hoop barns throughout finishing, and bedding is used to absorb animal waste, which results in minimal effluent. The objective of this study was to compare the performance and carcass characteristics of finishing beef steers (n = 1,428) managed in a bedded hoop-barn management system vs. an open-feedlot system with shelter. Six feeding trials were conducted over a 3-yr period. Three trials were conducted during summer-fall and 3 trials were conducted during winter-spring. Crossbred steers were allotted to 3 pens in the hoop-barn system and to 3 pens in the open-lot system (approximately 40 steers per pen in both facility systems). Stocking densities for the steers were 4.65 m(2) per steer in the hoop-barn system and 14.7 m(2) per steer in the open-lot system. The steers were begun on trial weighing 410 and 411 kg (SD = 21), were fed for 102.3 and 103.0 d (SD = 3.8), and were weighed off test at 595 and 602 kg (SD = 21) for the hoop-barn and open-lot systems, respectively. Steer performance measures consisted of ADG, DMI, and G:F. Carcass characteristics were HCW, fat thickness, LM area, KPH percentage, marbling score, USDA yield grade, and USDA quality grade. No year, season, or pen (management system) main effects, or season x management system and year x management system interactions were observed for any of the items measured related to cattle performance or carcass characteristics (P > 0.05). Final mud scores (a subjective evaluation of the amount of soil and manure adhering to the hair coat of the animals) were greater for the steers from the open-lot system compared with those from the hoop-barn system (P < 0.02), suggesting steers in the hoop-barn system carried less mud than steers from the open-lot system. Average daily cornstalk bedding use in the hoop-barn system was 2.3 kg/steer during summer-fall and 2

  2. Representation of spatial and spectro-temporal cues in the midbrain and forebrain of North American barn owls (Tyto furcata pratincola)

    OpenAIRE

    2015-01-01

    The barn owl is a crepuscular and nocturnal bird of prey that relies mainly on its acoustic system for the identification and localization of potential prey. The barn owl is able to localize even faint sounds in a natural environment precisely. Like mammals, barn owls use the interaural time difference (ITD) for the localization of the azimuthal sound source position. In the barn owl’s auditory system, ITD is processed in two separate pathways, the midbrain and forebrain pathways, which are b...

  3. The Strategy to Increase Women Farmer's Participation in the Program of Village Food Barn in East Java

    Science.gov (United States)

    Yuliatia, Yayuk; Iskaskar, Riyanti

    2016-01-01

    Food Barn Village Programme is one of the government's efforts in achieving household food security which includes four components. The purpose of this study was to develop a strategy to increase women's participation in the Food Barn Village Programme. This research was conducted in three villages in the district of Malang, namely: Village…

  4. Prey composition modulates exposure risk to anticoagulant rodenticides in a sentinel predator, the barn owl.

    Science.gov (United States)

    Geduhn, Anke; Esther, Alexandra; Schenke, Detlef; Gabriel, Doreen; Jacob, Jens

    2016-02-15

    Worldwide, small rodents are main prey items for many mammalian and avian predators. Some rodent species have pest potential and are managed with anticoagulant rodenticides (ARs). ARs are consumed by target and non-target small mammals and can lead to secondary exposure of predators. The development of appropriate risk mitigation strategies is important and requires detailed knowledge of AR residue pathways. From July 2011 to October 2013 we collected 2397 regurgitated barn owl (Tyto alba) pellets to analyze diet composition of owls on livestock farms in western Germany. 256 of them were fresh pellets that were collected during brodifacoum baiting. Fresh pellets and 742 liver samples of small mammals that were trapped during baiting in the same area were analyzed for residues of ARs. We calculated exposure risk of barn owls to ARs by comparing seasonal diet composition of owls with AR residue patterns in prey species. Risk was highest in autumn, when barn owls increasingly preyed on Apodemus that regularly showed AR residues, sometimes at high concentrations. The major prey species (Microtus spp.) that was consumed most frequently in summer had less potential to contribute to secondary poisoning of owls. There was no effect of AR application on prey composition. We rarely detected ARs in pellets (2 of 256 samples) but 13% of 38 prey individuals in barn owl nests were AR positive and substantiated the expected pathway. AR residues were present in 55% of 11 barn owl carcasses. Fluctuation in non-target small mammal abundance and differences in AR residue exposure patterns in prey species drives exposure risk for barn owls and probably other predators of small mammals. Exposure risk could be minimized through spatial and temporal adaption of AR applications (avoiding long baiting and non-target hot spots at farms) and through selective bait access for target animals.

  5. Trace metals in primary feathers of the Barn Owl (Tyto alba guttatus) in The Netherlands.

    Science.gov (United States)

    Denneman, W D; Douben, P E

    1993-01-01

    The number of Barn Owls in The Netherlands has been reduced substantially over the last few decades. Death as a result of poisoning seems unlikely, but the pathology of all bird species found dead in The Netherlands between 1975 and 1988 (n = 15 422) shows that 21% of all the birds were contaminated. However, the most important factor responsible for the decline in Barn Owl numbers in The Netherlands has not yet been established. As a part of a new national protection plan for the Barn Owl, the role of heavy metals has been investigated. Concentrations of heavy metals in the primary feathers of the Barn Owl varied according to their position in the wing; especially As, Sb, Fe and Zn whose concentrations depended on the place of the primary feather in the wing and the part of the vane which is used for the monitoring. The HS7 feather vane appears to provide a good estimate, even though the metal concentrations of this feather are always slightly lower than the concentrations in mixed samples of all ten primaries. It is recommended that they are used as a standard. Many factors affect metal concentrations. Increasing levels with age are found, presumably because metals are stored during growth at the end of the feathers as a method of reducing possible harmful effects. No significant correlations were found between the metal concentrations in the organs and those in the feather. Kidney and liver concentrations are always lower than the generally accepted levels for pathological damage of these organs. Even though metal concentrations in Barn Owl feathers are high compared with those reported for other birds in the Netherlands, it is concluded that Barn Owls are not adversely affected by current levels of heavy metal contamination in The Netherlands.

  6. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  7. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  8. Reactor Neutrinos

    Directory of Open Access Journals (Sweden)

    Soo-Bong Kim

    2013-01-01

    Full Text Available We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very recently the most precise determination of the neutrino mixing angle θ13. This paper provides an overview of the upcoming experiments and of the projects under development, including the determination of the neutrino mass hierarchy and the possible use of neutrinos for society, for nonproliferation of nuclear materials, and geophysics.

  9. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  10. Reactor Engineering

    Science.gov (United States)

    Lema, Juan M.; López, Carmen; Eibes, Gemma; Taboada-Puig, Roberto; Moreira, M. Teresa; Feijoo, Gumersindo

    In this chapter, the engineering aspects of processes catalyzed by peroxidases will be presented. In particular, a discussion of the existing technologies that utilize peroxidases for different purposes, such as the removal of recalcitrant compounds or the synthesis of polymers, is analyzed. In the first section, the essential variables controlling the process will be investigated, not only those that are common in any enzymatic system but also those specific to peroxidative reactions. Next, different reactor configurations and operational modes will be proposed, emphasizing their suitability and unsuitability for different systems. Finally, two specific reactors will be described in detail: enzymatic membrane reactors and biphasic reactors. These configurations are especially valuable for the treatment of xenobiotics with high and poor water solubility, respectively.

  11. Reactor Neutrinos

    OpenAIRE

    Lasserre, T.; Sobel, H.W.

    2005-01-01

    We review the status and the results of reactor neutrino experiments, that toe the cutting edge of neutrino research. Short baseline experiments have provided the measurement of the reactor neutrino spectrum, and are still searching for important phenomena such as the neutrino magnetic moment. They could open the door to the measurement of coherent neutrino scattering in a near future. Middle and long baseline oscillation experiments at Chooz and KamLAND have played a relevant role in neutrin...

  12. The barn owl wing: an inspiration for silent flight in the aviation industry?

    Science.gov (United States)

    Bachmann, Thomas; Mühlenbruch, Georg; Wagner, Hermann

    2011-04-01

    Barn owls are specialists in prey detection using acoustic information. The flight apparatus of this bird of prey is most efficiently adapted to the hunting behavior by reducing flight noise. An understanding of the underlying mechanisms owls make use of could help minimize the noise disturbances in airport or wind power plant neighborhood. Here, we characterize wings of barn owls in terms of an airfoil as a role model for studying silent flight. This characterization includes surface and edge specialization (serrations, fringes) evolved by the owl. Furthermore, we point towards possible adaptations of either noise suppression or air flow control that might be an inspiration for the construction of modern aircraft. Three-dimensional imaging techniques such as surface digitizing, computed tomography and confocal laser scanning microscopy were used to investigate the wings and feathers in high spatial resolution. We show that wings of barn owls are huge in relation to their body mass resulting in a very low wing loading which in turn enables a slow flight and an increased maneuverability. Profiles of the wing are highly cambered and anteriorly thickened, especially at the proximal wing, leading to high lift production during flight. However, wind tunnel experiments showed that the air flow tends to separate at such wing configurations, especially at low-speed flight. Barn owls compensated this problem by evolving surface and edge modifications that stabilize the air flow. A quantitative three-dimensionally characterization of some of these structures is presented.

  13. Non-planar Feynman diagrams and Mellin-Barnes representations with AMBRE 3.0

    Energy Technology Data Exchange (ETDEWEB)

    Dubovyk, Ievgen [Institute of Electrophysics and Radiation Technologies, Kharkiv (Ukraine); Gluza, Janusz [Univ. of Silesia, Katowice (Poland). Inst. of Physics; Riemann, Tord

    2016-04-15

    We introduce the Mellin-Barnes representation of general Feynman integrals and discuss their evaluation. The Mathematica package AMBRE has been recently extended in order to cover consistently non-planar Feynman integrals with two loops. Prospects for the near future are outlined. This write-up is an introduction to new results which have also been presented elsewhere.

  14. Mellem behovsorientering og regulering - diskurser om det omsorg for det lille barn

    DEFF Research Database (Denmark)

    Pedersen, Oline

    2013-01-01

    En artikel der på baggrund af feltarbejde i den danske sundhedsplejen søger at indfange, hvor diskursen om omsorg for det lille barn befinder sig i spændingsfeltet mellem at regulere barnet eller at følge dets signaler og behov....

  15. Estimation of nitrogen volatilisation in the bedded-pack of dairy cow barns

    Directory of Open Access Journals (Sweden)

    Antonello Cannas

    2010-01-01

    Full Text Available The objective of the study was to measure N volatilisation (NVOL from bedded-pack dairy cow barns. Feed intake, milk production, bedding material used and meteorological variables were monitored in 3 dairy farms near the town of Arborea (39°46’26” N, 08°34’53” E, 7 m a.s.l. during one month for each season from summer 2007 to spring 2008. NVOL was measured in the interval between excretion and removal of bedded-packs from barn floors. NVOL was measured using the N (nitrogen to P (phosphorus ratio marker method, considering P as an internal non-volatile marker in milk and manure. Nitrogen and P excretion was estimated by nutrient balance as intake minus N and P excreted in milk. NVOL coefficient and bad-pack temperature were almost constant among seasons. The annual mean NVOL in bedded-pack barns was equal to 38.8% of excreted N. Accounting also for the NVOL that occurred in the concrete floor of the feeding and walking areas of the barns, NVOL was 40.7% of N excreted.

  16. Animal welfare in cross-ventilated, compost-bedded pack, and naturally ventilated dairy barns in the upper Midwest.

    Science.gov (United States)

    Lobeck, K M; Endres, M I; Shane, E M; Godden, S M; Fetrow, J

    2011-11-01

    The objective of this cohort study was to investigate animal welfare in 2 newer dairy housing options in the upper Midwest, cross-ventilated freestall barns (CV) and compost-bedded-pack barns (CB), compared with conventional, naturally ventilated freestall barns (NV). The study was conducted on 18 commercial dairy farms, 6 of each housing type, in Minnesota and eastern South Dakota. The primary breed in all farms was Holstein; 1 CV and 1 NV herd had approximately 30% Jersey-Holstein crossbreds. All freestall herds used sand for bedding. Farms were visited 4 times (once in each season) between January and November 2008, and approximately 93% of all animals in each pen were visually scored on each visit. Outcome-based measurements of welfare (locomotion, hock lesions, body condition score, hygiene, respiration rates, mortality, and mastitis prevalence) were collected on each farm. Lameness prevalence (proportion of cows with locomotion score ≥3 on a 1 to 5 scale, where 1=normal and 5=severely lame) in CB barns (4.4%) was lower than that in NV (15.9%) and CV (13.1%) barns. Lameness prevalence was similar between CV and NV barns. Hock lesion prevalence (proportion of cows with a lesion score ≥2 on a 1 to 3 scale, where 1=normal, 2=hair loss, and 3=swelling) was lower in CB barns (3.8%) than in CV (31.2%) and NV barns (23.9%). Hygiene scores (1 to 5 scale, where 1=clean and 5=very dirty) were higher for CB (3.18) than CV (2.83) and NV (2.77) barns, with no differences between CV and NV barns. Body condition scores, respiration rates, mastitis prevalence, culling, and mortality rates did not differ among housing systems. The CV and NV barns were evaluated using the cow comfort index (proportion of cows lying down in a stall divided by all animals touching a stall) and the stall usage index (proportion of cows lying divided by all animals in the pen not eating). The CV barns tended to have greater cow comfort index (85.9%) than the NV barns (81.4%) and had greater

  17. Microsatellite markers characterized in the barn owl (Tyto alba) and of high utility in other owls (Strigiformes: AVES).

    Science.gov (United States)

    Klein, Akos; Horsburgh, Gavin J; Küpper, Clemens; Major, Agnes; Lee, Patricia L M; Hoffmann, Gyula; Mátics, Róbert; Dawson, Deborah A

    2009-11-01

    We have identified 15 polymorphic microsatellite loci for the barn owl (Tyto alba), five from testing published owl loci and 10 from testing non-owl loci, including loci known to be of high utility in passerines and shorebirds. All 15 loci were sequenced in barn owl, and new primer sets were designed for eight loci. The 15 polymorphic loci displayed two to 26 alleles in 56-58 barn owls. When tested in 10 other owl species (n = 1-6 individuals), between four and nine loci were polymorphic per species. These loci are suitable for studies of population structure and parentage in owls.

  18. On Barnes Beta Distributions and Applications to the Maximum Distribution of the 2D Gaussian Free Field

    Science.gov (United States)

    Ostrovsky, Dmitry

    2016-09-01

    A new family of Barnes beta distributions on (0, ∞) is introduced and its infinite divisibility, moment determinacy, scaling, and factorization properties are established. The Morris integral probability distribution is constructed from Barnes beta distributions of types (1, 0) and (2, 2), and its moment determinacy and involution invariance properties are established. For application, the maximum distributions of the 2D gaussian free field on the unit interval and circle with a non-random logarithmic potential are conjecturally related to the critical Selberg and Morris integral probability distributions, respectively, and expressed in terms of sums of Barnes beta distributions of types (1, 0) and (2, 2).

  19. Bioconversion reactor

    Science.gov (United States)

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  20. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  1. Semi-annual monitoring report for Barnes, Kansas, for July-December 2009.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2010-04-27

    The Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) operated a grain storage facility at Barnes, Kansas, during most of the interval 1949-1974. Carbon tetrachloride contamination was initially detected in 1986 in the town's public water supply wells. In 2006-2007, the CCC/USDA conducted a comprehensive targeted investigation at and near its former property in Barnes to characterize this contamination. Those results were reported previously (Argonne 2008a). In November 2007, the CCC/USDA began quarterly groundwater monitoring at Barnes. The monitoring is being conducted on behalf of the CCC/USDA by Argonne National Laboratory, in accord with the recommendations made in the report for the 2006-2007 targeted investigation (Argonne 2008a). The objective is to monitor the carbon tetrachloride contamination identified in the groundwater at Barnes. The sampling is presently conducted in a network of 28 individual monitoring wells (at 19 distinct locations), 2 public water supply wells, and 1 private well (Figure 1.1). The results of the 2006-2007 targeted investigation and the subsequent monitoring events (Argonne 2008a-d, 2009a,b) demonstrated the presence of carbon tetrachloride contamination in groundwater at levels exceeding the Kansas Department of Health and Environment (KDHE) Tier 2 risk-based screening level (RBSL) of 5.0 {micro}g/L for this compound. The contaminant plume appears to extend from the former CCC/USDA property northwestward, toward the Barnes public water supply wells. Information obtained during the 2006-2007 investigation indicates that at least one other potential source might have contributed to the groundwater contaminant plume (Argonne 2008a). The former agriculture building owned by the local school district, located immediately east of well PWS3, is also a potential source of the contamination. This current report presents the results of the seventh quarterly monitoring event, conducted in September

  2. Sex steroid hormones in barn swallow (Hirundo rustica) populations at a dioxin contaminated site in northeast Louisiana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study compares the gonadal sex steroid hormone levels (i.e., estradiol, total estrogen, and testosterone) in Louisiana barn swallows (Hirundo rustica) that were...

  3. Remaining Sites Verification Package for the 141-C Large Animal Barn and Biology Laboratory (Hog Barn), Waste Site Reclassification Form 2006-027

    Energy Technology Data Exchange (ETDEWEB)

    R. A. Carlson

    2006-05-24

    The 141-C waste site is a former large animal barn and biology laboratory within the 100-F Area experimental animal farm. Strontium-90, arsenic, and multiple polycyclic aromatic hydrocarbons were detected within residual demolition debris at concentrations exceeding cleanup criteria. The site has been remediated by removing approximately 900 bank cubic meters of soil and debris within the former building footprint to the Environmental Restoration Disposal Facility. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

  4. Avian pox virus infection in a common barn owl (Tyto alba in southern Brazil

    Directory of Open Access Journals (Sweden)

    Gilberto D. Vargas

    2011-07-01

    Full Text Available A young common barn owl (Tyto alba was referred to the Núcleo de Reabilitação da Fauna Silvestre (Nurfs, Federal University of Pelotas (UFPel, after been found in a barn of a brick factory in the urban area of Pelotas, Rio Grande do Sul, Brazil. The bird was apathic, weak and with crusty lesions in the featherless areas (eyes, beak, legs, and died soon after arrival at Nurfs. Necropsy and histopathological examination of the lesions were carried out. The hyperplasia and hypertrophy of the cutaneous lesions, several eosinophilic intracyto-plasmic inclusion bodies in epithelial cells (Bollinger bodies, as well as particles characteristic of poxvirus, observed by electronic microscopy, confirmed the infection by avian poxvirus, what highlights the importance of Tyto alba as carrier of the virus in the wild.

  5. Multimodal signalling in the North American barn swallow: a phenotype network approach

    Science.gov (United States)

    Wilkins, Matthew R.; Shizuka, Daizaburo; Joseph, Maxwell B.; Hubbard, Joanna K.; Safran, Rebecca J.

    2015-01-01

    Complex signals, involving multiple components within and across modalities, are common in animal communication. However, decomposing complex signals into traits and their interactions remains a fundamental challenge for studies of phenotype evolution. We apply a novel phenotype network approach for studying complex signal evolution in the North American barn swallow (Hirundo rustica erythrogaster). We integrate model testing with correlation-based phenotype networks to infer the contributions of female mate choice and male–male competition to the evolution of barn swallow communication. Overall, the best predictors of mate choice were distinct from those for competition, while moderate functional overlap suggests males and females use some of the same traits to assess potential mates and rivals. We interpret model results in the context of a network of traits, and suggest this approach allows researchers a more nuanced view of trait clustering patterns that informs new hypotheses about the evolution of communication systems. PMID:26423842

  6. Multimodal signalling in the North American barn swallow: a phenotype network approach.

    Science.gov (United States)

    Wilkins, Matthew R; Shizuka, Daizaburo; Joseph, Maxwell B; Hubbard, Joanna K; Safran, Rebecca J

    2015-10-01

    Complex signals, involving multiple components within and across modalities, are common in animal communication. However, decomposing complex signals into traits and their interactions remains a fundamental challenge for studies of phenotype evolution. We apply a novel phenotype network approach for studying complex signal evolution in the North American barn swallow (Hirundo rustica erythrogaster). We integrate model testing with correlation-based phenotype networks to infer the contributions of female mate choice and male-male competition to the evolution of barn swallow communication. Overall, the best predictors of mate choice were distinct from those for competition, while moderate functional overlap suggests males and females use some of the same traits to assess potential mates and rivals. We interpret model results in the context of a network of traits, and suggest this approach allows researchers a more nuanced view of trait clustering patterns that informs new hypotheses about the evolution of communication systems.

  7. Geographic variation in sexual selection and implications for speciation in the Barn Swallow

    Institute of Scientific and Technical Information of China (English)

    Elizabeth; SC; Scordato; Rebecca; J; Safran

    2015-01-01

    Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.

  8. Att stärka delaktigheten hos barn med autism på daghem : En litteraturstudie

    OpenAIRE

    Rikberg, Sofie

    2012-01-01

    Idag strävas det efter att barn med lindrigare former av autism så långt som möjligt skall integreras i daghem. På grund av de svårigheter som barnet med autism har löper det risk att bli utanför gemenskapen på daghemmet. Examensarbetet beskriver i form av en litteraturstudie beskriva hur de professionella kan stärka delaktigheten hos barn med autism på daghem och därmed främja möjligheterna till social inklusion. Frågeställningen är följande: Hur kan professionella forma verksamheten på dag...

  9. Geographic variation in sexual selection and implications for speciation in the Barn Swallow

    Institute of Scientific and Technical Information of China (English)

    Elizabeth SC Scordato; Rebecca J Safran

    2015-01-01

    Barn Swal ows (Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements. A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies. We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographical y. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.

  10. Improvement of directionality and sound-localization by internal ear coupling in barn owls

    DEFF Research Database (Denmark)

    Wagner, Hermann; Christensen-Dalsgaard, Jakob; Kettler, Lutz

    . However, despite intensive research during the last 40 years it is still unclear whether and how internal ear coupling contributes to sound localization in the barn owl. Here we investigated ear directionality in anesthetized birds with the help of laser vibrometry. Care was taken that anesthesia......Mark Konishi was one of the first to quantify sound-localization capabilities in barn owls. He showed that frequencies between 3 and 10 kHz underlie precise sound localization in these birds, and that they derive spatial information from processing interaural time and interaural level differences...... and the stapedius reflex did not influence the results. When analyzed in narrow frequency bands, the data demonstrated a certain amount of internal ear coupling in the low-frequnecy range (

  11. The Torments of Spring: Jake Barnes's Phantom Limb in The Sun Also Rises.

    Science.gov (United States)

    Anesko, Michael

    2015-01-01

    While critics recently have found The Sun Also Rises a fruitful text for reexamining issues of gender and sexuality in Hemingway's work, a significant aspect of Jake Barnes's genital wounding has been overlooked. At least from the time of the American Civil War, a diverse body of medical literature has documented the psychosomatic reality of phantom genitalia in traumatically injured men. Revisiting the novel from this perspective-imagining that Jake Barnes is haunted by a penile ghost-allows us to see this character as something more than a victim of disability. Instead, we might think of Jake's material self as figuratively masculine but accidentally transgendered: a body that others can desire and that still can choose, or not, to reciprocate sexual feeling.

  12. Compounding effects on nest-site dispersal of Barn Owls Tyto alba

    DEFF Research Database (Denmark)

    Huffeldt, Nicholas Per; Aggerholm, Iben Næs; Brandtberg, Nathia Hass

    2012-01-01

    Capsule Recovery distances of Barn Owls ringed as pulli are conditional on ringing date but not on population density. Aims To test whether ring recovery distances (proxy for natal dispersal distances) were conditional on population density and reproductive timing. Methods We used ringing data...... from 0 to 100 days after ringing, being stable thereafter, and was also impacted by brood size. Owls ringed very early or late in the breeding season were more likely to be recovered

  13. Performance and Health of Group-Housed Calves Kept in Igloo Calf Hutches and Calf Barn

    Directory of Open Access Journals (Sweden)

    Jerzy Wójcik*, Renata Pilarczyk, Anna Bilska, Ottfried Weiher1 and Peter Sanftleben1

    2013-04-01

    Full Text Available Group-reared calves are usually housed in common buildings, such as calf barns of all sorts; however, there are concerns about this practice due to problems such as an increased incidence of diseases and poor performance of the calves. Group calf rearing using igloo hutches may be a solution combining the benefits of individual and group housing systems. The aim of this study was to evaluate group-reared calves housed in Igloo-type hutches compared with those housed in common calf barns. The experiment was carried out on a large private dairy farm located in Vorpommern, Germany. A total of 90 Deutsche-Holstein bull calves were assigned to 2 treatment groups: the calf-barn group, with calves grouped in pens in a building, and the Igloo-hutch group, with calves housed in outdoor enclosures with an access to group igloo-style hutches. Calves entering the 84-day experiment were at an average age of about three weeks, with the mean initial body weight of about 50 kg. The calves housed in the group Igloo hutches attained higher daily weight gains compared to those housed in the calf barn (973 vs 721 g/day, consumed more solid feeds (concentrate, corn grain and maize silage: (1.79 vs 1.59 kg/day, and less milk replacer (5.51 vs 6.19 kg/day, had also a lower incidence of respiratory diseases (1.24 vs 3.57% with a shorter persistence of the illness.

  14. Archeological Testing at 32BA414, Lake Ashtabula, Barnes County, North Dakota.

    Science.gov (United States)

    1984-02-01

    and Block 1967:44). Thick glacial drift (as deep as 95 m) blankets Barnes County (Kelly and Block 1967:17). Glacial till is dense east of 32BA414 in the...many roots) North Wail Profile Sa1ndy LearN 10YR 312 SandY Loarn lOf 311 (fewrn oot*) Sandy Sit Lesrn lOY" 312 Toat Unit 6 Sand 16O1M 313 West Wall

  15. The double Mellin-Barnes type integrals and their applications to convolution theory

    CERN Document Server

    Hai, Nguyen Thanh

    1992-01-01

    This book presents new results in the theory of the double Mellin-Barnes integrals popularly known as the general H-function of two variables.A general integral convolution is constructed by the authors and it contains Laplace convolution as a particular case and possesses a factorization property for one-dimensional H-transform. Many examples of convolutions for classical integral transforms are obtained and they can be applied for the evaluation of series and integrals.

  16. Numerical integration of massive two-loop Mellin-Barnes integrals in Minkowskian regions

    Energy Technology Data Exchange (ETDEWEB)

    Dubovyk, Ievgen [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Gluza, Janusz [Uniwersytet Slaski, Katowice (Poland). Inst. Fizyki; Riemann, Tord [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Uniwersytet Slaski, Katowice (Poland). Inst. Fizyki; Usovitsch, Johann [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2016-07-15

    Mellin-Barnes (MB) techniques applied to integrals emerging in particle physics perturbative calculations are summarized. New versions of AMBRE packages which construct planar and nonplanar MB representations are shortly discussed. The numerical package MBnumerics.m is presented for the first time which is able to calculate with a high precision multidimensional MB integrals in Minkowskian regions. Examples are given for massive vertex integrals which include threshold effects and several scale parameters.

  17. Maps of ITD in the Nucleus Laminaris of the Barn Owl

    OpenAIRE

    Carr, Catherine; Shah, Sahil; Ashida, Go; McColgan, Thomas; Wagner, Hermann; Kuokkanen, Paula; Kempter, Richard; Köppl, Christine

    2013-01-01

    Axons from the nucleus magnocellularis (NM) and their targets in nucleus laminaris (NL) form the circuit responsible for encoding interaural time differences. In barn owls, NL receives bilateral inputs from NM such that axons from the ipsilateral NM enter NL dorsally, while contralateral axons enter from the ventral side. These afferents and their synapses on NL neurons generate a tone-induced local field potential, or neurophonic, that varies systematically with position in NL. From dorsal t...

  18. Mellin-Barnes representations of Feynman diagrams, linear systems of differential equations, and polynomial solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kalmykov, Mikhail Yu.; Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2012-05-15

    We argue that the Mellin-Barnes representations of Feynman diagrams can be used for obtaining linear systems of homogeneous differential equations for the original Feynman diagrams with arbitrary powers of propagators without recourse to the integration-by-parts technique. These systems of differential equation can be used (i) for the differential reductions to sets of basic functions and (ii) for counting the numbers of master-integrals.

  19. Female plumage spottiness signals parasite resistance in the barn owl (Tyto alba)

    OpenAIRE

    Roulin, A.; Riols, C; Dijkstra, C; Ducrest, A. L.

    2001-01-01

    The hypothesis that extravagant ornaments signal parasite resistance has received support in several species for ornamented males but more rarely for ornamented females. However, recent theories have proposed that females should often be under sexual selection, and therefore females may signal the heritable capacity to resist parasites. We investigated this hypothesis in the socially monogamous barn owl, Tyto alba, in which females exhibit on average more and larger black spots on the plumage...

  20. Breeding biology of the Barn Owl (Tyto alba) in the Lower Mainland of British Columbia

    Science.gov (United States)

    Lorraine A. Andrusiak; K. M. Cheng

    1997-01-01

    Breeding of the Barn Owl was studied from 1990-1992 in the Lower Mainland of British Columbia, the northern limit of the species' North American range. Over 3 years, mean clutch size was 6.5 ± 3.5, mean brood size at time of banding was 3.3 ± 2.0, and mean number of nestlings fledged was 2.6 ± 2.1. Clutch size ranged from 2 to 18 eggs....

  1. Evolutionary conservation of Kv3.1 in the barn owl Tyto alba.

    Science.gov (United States)

    Kullmann, Lars; Schlüter, Tina; Wagner, Hermann; Nothwang, Hans Gerd

    2013-01-01

    For prey capture in the dark, the barn owl Tyto alba has evolved into an auditory specialist with an exquisite capability of sound localization. Adaptations include asymmetrical ears, enlarged auditory processing centers, the utilization of minute interaural time differences, and phase locking along the entire hearing range up to 10 kHz. Adaptations on the molecular level have not yet been investigated. Here, we tested the hypothesis that divergence in the amino acid sequence of the voltage-gated K(+) channel Kv3.1 contributes to the accuracy and high firing rates of auditory neurons in the barn owl. We therefore cloned both splice variants of Kcnc1, the gene encoding Kv3.1. Both splice variants, Kcnc1a and Kcnc1b, encode amino acids identical to those of the chicken, an auditory generalist. Expression analyses confirmed neural-restricted expression of the channel. In summary, our data reveal strong evolutionary conservation of Kcnc1 in the barn owl and point to other genes involved in auditory specializations of this animal. The data also demonstrate the feasibility to address neuroethological questions in organisms with no reference genome by molecular approaches. This will open new avenues for neuroethologists working in these organisms.

  2. A Continent-Wide Migratory Divide in North American Breeding Barn Swallows (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Keith A Hobson

    Full Text Available Populations of most North American aerial insectivores have undergone steep population declines over the past 40 years but the relative importance of factors operating on breeding, wintering, or stopover sites remains unknown. We used archival light-level geolocators to track the phenology, movements and winter locations of barn swallows (Hirdundo rustica; n = 27 from populations across North America to determine their migratory connectivity. We identified an east-west continental migratory divide for barn swallows with birds from western regions (Washington State, USA (n = 8 and Saskatchewan, Canada (n = 5 traveling shorter distances to wintering areas ranging from Oregon to northern Colombia than eastern populations (Ontario (n = 3 and New Brunswick (n = 10, Canada which wintered in South America south of the Amazon basin. A single swallow from a stable population in Alabama shared a similar migration route to eastern barn swallows but wintered farther north in northeast Brazil indicating a potential leap frog pattern migratory among eastern birds. Six of 9 (67% birds from the two eastern populations and Alabama underwent a loop migration west of fall migration routes including around the Gulf of Mexico travelling a mean of 2,224 km and 722 km longer on spring migration, respectively. Longer migration distances, including the requirement to cross the Caribbean Sea and Gulf of Mexico and subsequent shorter sedentary wintering periods, may exacerbate declines for populations breeding in northeastern North America.

  3. Practical Encoders and Decoders for Euclidean Codes from Barnes-Wall Lattices

    CERN Document Server

    Harshan, J; Belfiore, Jean-Claude

    2012-01-01

    It is well known that dense lattice packings can be obtained via Construction $A$ from \\emph{binary} linear codes. In this paper, we propose an extension of Construction $A$ called Construction $A^\\prime$ to obtain Barnes-Wall lattices from linear codes over finite rings. To obtain the Barnes-Wall lattice $BW_{2^{m}}$ in $\\mathbb{C}^{2^{m}}$ for any $m \\geq 1$, we identify a linear code $\\mathcal{C}_{2^m}$ over a polynomial ring and then embed the linear code to a lattice constellation $\\mathcal{L}_{2^{m}}$ such that $BW_{2^{m}}$ can be obtained as $BW_{2^{m}} = (1+i)^{m}\\mathbb{Z}[i]^{2^{m}} \\oplus \\mathcal{L}_{2^{m}}$ where $i = \\sqrt{-1}$. We also show that $\\mathcal{L}_{2^{m}}$ has the cubic shaping property when $m$ is even. We highlight that Construction $A^\\prime$ provides a convenient technique for bit-labelling Barnes-Wall lattice constellations. We also employ the lattice constellation $\\mathcal{L}_{2^{m}}$ as a coded modulation scheme for AWGN channels. To encode the code, we use Construction $A^{\\...

  4. Time budgets of finishing bulls housed in an uninsulated barn or at pasture

    Directory of Open Access Journals (Sweden)

    Leena Tuomisto

    2015-10-01

    Full Text Available This study aimed at comparing the behaviour of finishing bulls raised in an uninsulated barn (UB and at pasture (PAS. In experiment 1, dairy bulls were housed in an uninsulated barn (two groups of five bulls, 32 m2/pen or at pasture (groups of four and five bulls, 5000 m2/paddock. In experiment 2, Hereford bulls were housed in an uninsulated barn (three groups of four or five bulls, 32 m2/pen or at pasture (three groups of five bulls, 5000 m2/paddock. There were no differences in drinking, social licking, butting, other social behaviour, self-licking or idling between the UB and PAS bulls. The UB bulls spent more time in lying, ruminating, oral explorative and manipulative behaviour and rubbing and less time foraging and walking than the PAS bulls. The UB bulls performed more social licking and oral manipulation of objects and less mounting than the PAS bulls. These differences resulted most probably from the different feeding regimes and different space allowances.

  5. Rainfall estimates for hydrological models: Comparing rain gauge, radar and microwave link data as input for the Wageningen Lowland Runoff Simulator (WALRUS)

    Science.gov (United States)

    Brauer, Claudia; Overeem, Aart; Uijlenhoet, Remko

    2015-04-01

    Several rainfall measurement techniques are available for hydrological applications, each with its own spatial and temporal resolution. We investigated the effect of differences in rainfall estimates on discharge simulations in a lowland catchment by forcing a novel rainfall-runoff model (WALRUS) with rainfall data from gauges, radars and microwave links. The hydrological model used for this analysis is the recently developed Wageningen Lowland Runoff Simulator (WALRUS). WALRUS is a rainfall-runoff model accounting for hydrological processes relevant to areas with shallow groundwater (e.g. groundwater-surface water feedback). Here, we used WALRUS for case studies in the Hupsel Brook catchment. We used two automatic rain gauges with hourly resolution, located inside the catchment (the base run) and 30 km northeast. Operational (real-time) and climatological (gauge-adjusted) C-band radar products and country-wide rainfall maps derived from microwave link data from a cellular telecommunication network were also used. Discharges simulated with these different inputs were compared to observations. Traditionally, the precipitation research community places emphasis on quantifying spatial errors and uncertainty, but for hydrological applications, temporal errors and uncertainty should be quantified as well. Its memory makes the hydrologic system sensitive to missed or badly timed rainfall events, but also emphasizes the effect of a bias in rainfall estimates. Systematic underestimation of rainfall by the uncorrected operational radar product leads to very dry model states and an increasing underestimation of discharge. Using the rain gauge 30 km northeast of the catchment yields good results for climatological studies, but not for forecasting individual floods. Simulating discharge using the maps derived from microwave link data and the gauge-adjusted radar product yields good results for both events and climatological studies. This indicates that these products can be

  6. Barn og fysisk aktivitet i barnehagen: Hvordan kan aktivitetsnivået dokumenteres?

    Directory of Open Access Journals (Sweden)

    Anne Stokke

    2014-12-01

    Full Text Available Abstract: We monitored the physical activity levels of 42 children during a regular day in kindergarten, using various instruments. This study will provide knowledge about children’s activity levels in kindergarten. It also discusses whether children’s activity levels can be adequately evaluated by the teachers or if there is a need for technical measurements. In addition, we compared the different instruments used to evaluate the children. The employees in the kindergarten were asked to answer a questionnaire about the children’s physical activity level during the day, and a student or a researcher observed and registered one child each. During the same day, activity levels were monitored using actigraphy (AC; Actigraf GT3X and continuous heart rate monitoring (HR; Team2 Polar ® in 14 children (six boys and eight girls, 38 and 47 months old, respectively. The researcher-observations defined the observed children as “moderately active”, and AC-data showed that all children had more than 60 minutes of moderate - or high - intensity activity. According to our comparisons, the use of HR to assess the activity in kindergartens is not recommended. On average, the questionnaires reported similar physical activity levels for the same child, although the evaluations varied between employees. When comparing one active and one inactive child, the different methods showed similar results. We conclude that professionals can see a child’s physical activity level when asked to reflect upon it.Sammendrag: Vi målte det fysiske aktivitetsnivået til 42 barn i løpet av en vanlig dag i barnehagen ved hjelp av ulike instrumenter. Denne studien vil gi kunnskap om barns fysiske aktivitet i barnehagen, og om barnas aktivitetsnivå kan bli tilstrekkelig evaluert av lærerne eller om det er behov for tekniske målinger. Videre har vi sammenlignet de ulike instrumentene brukt i observasjonen. De ansatte i barnehagen ble bedt om å svare på et sp

  7. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    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.

  8. D and DR Reactors

    Data.gov (United States)

    Federal Laboratory Consortium — The world's second full-scale nuclear reactor was the D Reactor at Hanford which was built in the early 1940's and went operational in December of 1944.D Reactor ran...

  9. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    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.

  10. Nuclear reactor neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Speaker, Daniel P; Neeley, Gary W; Inman, James B

    2017-09-12

    A nuclear reactor includes a reactor pressure vessel and a nuclear reactor core comprising fissile material disposed in a lower portion of the reactor pressure vessel. The lower portion of the reactor pressure vessel is disposed in a reactor cavity. An annular neutron stop is located at an elevation above the uppermost elevation of the nuclear reactor core. The annular neutron stop comprises neutron absorbing material filling an annular gap between the reactor pressure vessel and the wall of the reactor cavity. The annular neutron stop may comprise an outer neutron stop ring attached to the wall of the reactor cavity, and an inner neutron stop ring attached to the reactor pressure vessel. An excore instrument guide tube penetrates through the annular neutron stop, and a neutron plug comprising neutron absorbing material is disposed in the tube at the penetration through the neutron stop.

  11. The Binaural Interaction Component in Barn Owl (Tyto alba) Presents few Differences to Mammalian Data.

    Science.gov (United States)

    Palanca-Castan, Nicolas; Laumen, Geneviève; Reed, Darrin; Köppl, Christine

    2016-12-01

    The auditory brainstem response (ABR) is an evoked potential that reflects the responses to sound by brainstem neural centers. The binaural interaction component (BIC) is obtained by subtracting the sum of the monaural ABR responses from the binaural response. Its latency and amplitude change in response to variations in binaural cues. The BIC is thus thought to reflect the activity of binaural nuclei and is used to non-invasively test binaural processing. However, any conclusions are limited by a lack of knowledge of the relevant processes at the level of individual neurons. The aim of this study was to characterize the ABR and BIC in the barn owl, an animal where the ITD-processing neural circuits are known in great detail. We recorded ABR responses to chirps and to 1 and 4 kHz tones from anesthetized barn owls. General characteristics of the barn owl ABR were similar to those observed in other bird species. The most prominent peak of the BIC was associated with nucleus laminaris and is thus likely to reflect the known processes of ITD computation in this nucleus. However, the properties of the BIC were very similar to previously published mammalian data and did not reveal any specific diagnostic features. For example, the polarity of the BIC was negative, which indicates a smaller response to binaural stimulation than predicted by the sum of monaural responses. This is contrary to previous predictions for an excitatory-excitatory system such as nucleus laminaris. Similarly, the change in BIC latency with varying ITD was not distinguishable from mammalian data. Contrary to previous predictions, this behavior appears unrelated to the known underlying neural delay-line circuitry. In conclusion, the generation of the BIC is currently inadequately understood and common assumptions about the BIC need to be reconsidered when interpreting such measurements.

  12. Representation of interaural time difference in the central nucleus of the barn owl's inferior colliculus.

    Science.gov (United States)

    Wagner, H; Takahashi, T; Konishi, M

    1987-10-01

    This paper investigates the role of the central nucleus of the barn owl's inferior colliculus in determination of the sound-source azimuth. The central nucleus contains many neurons that are sensitive to interaural time difference (ITD), the cue for azimuth in the barn owl. The response of these neurons varies in a cyclic manner with the ITD of a tone or noise burst. Response maxima recur at integer multiples of the period of the stimulating tone, or, if the stimulus is noise, at integer multiples of the period corresponding to the neuron's best frequency. Such neurons can signal, by means of their relative spike rate, the phase difference between the sounds reaching the left and right ears. Since an interaural phase difference corresponds to more than one ITD, these neurons represent ITD ambiguously. We call this phenomenon phase ambiguity. The central nucleus is tonotopically organized and its neurons are narrowly tuned to frequency. Neurons in an array perpendicular to isofrequency laminae form a physiological and anatomical unit; only one ITD, the array-specific ITD, activates all neurons in an array at the same relative level. We, therefore, may say that, in the central nucleus, an ITD is conserved in an array of neurons. Array-specific ITDs are mapped and encompass the entire auditory space of the barn owl. Individual space-specific neurons of the external nucleus, which receive inputs from a wide range of frequency channels (Knudsen and Konishi, 1978), are selective for a unique ITD. Space-specific neurons do not show phase ambiguity when stimulated with noise (Takahashi and Konishi, 1986). Space-specific neurons receive inputs from arrays that are selective for the same ITD. The collective response of the neurons in an array may be the basis for the absence of phase ambiguity in space-specific neurons.

  13. Effect of scraping frequency in a freestall barn on volatile nitrogen loss from dairy manure.

    Science.gov (United States)

    Moreira, V R; Satter, L D

    2006-07-01

    The objective of this investigation was to evaluate the effect of scraping frequency (2x vs. 6x daily) on N volatilization from manure on the floor of a dairy free-stall barn. Three trials (crossover design) were conducted in the summers of 2001 and 2002, and in the winter of 2003. Nitrogen volatilization was estimated from the change in the N:P ratio in excreta at the time of excretion to the time when manure was scraped from the barn. Total N loss was considered a maximum estimate of NH3-N loss, because small amounts of nonammonia N may be volatilized. Nitrogen was determined after manure subsamples were lyophilized; P content was measured by direct current emission spectroscopy of ashed subsamples of manure. Lactating dairy cows were fed high-protein (18.5 to 19.3% crude protein), alfalfa-based diets. Average milk yield was 31.9 (SD = 7.4) kg/d. Scraping frequency had no effect on N loss in summer 2001. An average of 41% of excreted N, or 238 +/- 19.0 g of N/d per cow, was volatilized. For the trial in summer 2002, nitrogen volatilization was reduced from 50% of the excreted N with 2x to 46.7% with 6x, equivalent to 265 and 248 g of N lost/d per cow, respectively. Scraping had no effect on N volatilization during the winter trial. An average of 17.7% of excreted N was volatilized during the winter, equivalent to 109 +/- 11.0 g of N lost/d per cow. Scraping frequency of manure had little or no effect on N loss from manure in a freestall barn. Nitrogen loss during the winter was less than half of the loss during the summer.

  14. Reactor and method of operation

    Science.gov (United States)

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  15. ”Vissa barn älskar faktiskt sånna dära TV-reklamer” : - En övergripande studie om hur barn upplever och tolkar TV-reklam -

    OpenAIRE

    Norberg, Lotta

    2007-01-01

    ABSTRACT Titel: “Some kids really love those commercials” -A study of how children experience and construe commercials. (Vissa barn älskar faktiskt sånna dära TV-reklamer” – En övergripande studie om hur barn upplever och tolkar tv-reklam.) Number of pages: 40 Author: Lotta Norberg Tutor: Amelie Hössjer Course: Media and Communication Studies C Period: Autumn term 2007 University: Division of Media and Communication, Department of Information Science, Uppsala University Purpose/Aim: The aim o...

  16. Kortisonskepsis : En studie om holdninger til kortisonkrem blant foreldre av barn med atopisk eksem

    OpenAIRE

    Gustavsen, Hanne Engstrøm

    2010-01-01

    Bakgrunn: Kortisonkremer er en viktig del av behandlingen mot atopisk eksem. Mange foreldre er skeptiske til bruken av kortisonkremer, fordi de har lest eller hørt om bivirkninger. Pasienters og pårørendes holdninger til bruk av kortisonkrem kan påvirke gjennomføringen av behandlingen. Formål: Vi ønsket å undersøke holdninger til bruk av kortisonkrem blant foreldre og pårørende av barn med atopisk eksem. Vi ville også undersøke om det er en sammenheng mellom kunnskapsnivå om kortisonkreme...

  17. Contingency interim measure for the public water supply at Barnes, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2009-07-09

    This document presents a conceptual design for a contingency interim measure (IM) for treatment of the public water supply system at Barnes, Kansas, should this become necessary. The aquifer that serves the public water supply system at Barnes has been affected by trace to low concentrations of carbon tetrachloride and its degradation product, chloroform. Investigations conducted on behalf of the CCC/USDA by Argonne National Laboratory (Argonne 2008a) have demonstrated that groundwater at the Barnes site is contaminated with carbon tetrachloride at concentrations exceeding the Kansas Tier 2 risk-based screening level (RBSL) and the EPA maximum contaminant level (MCL) of 5.0 {micro}g/L for this compound. The Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) formerly operated a grain storage facility in Barnes, approximately 800 ft east-southeast of the public water supply wells. Carbon tetrachloride was used in the treatment of grain. Another potential source identified in an investigation conducted for the KDHE (PRC 1996) is the site of a former agriculture building owned by the local school district (USD 223). This building is located immediately east of well PWS3. The potential contingency IM options evaluated in this report include the treatment of groundwater at the public water supply wellheads and the provision of an alternate water supply via Washington County Rural Water District No.2 (RWD 2). This document was developed in accordance with KDHE Bureau of Environmental Remediation (BER) Policy No.BER-RS-029 (Revised) (KDHE 2006a), supplemented by guidance from the KDHE project manager. Upon the approval of this contingency IM conceptual design by the KDHE, the CCC/USDA will prepare a treatment system design document that will contain the following elements: (1) Description of the approved contingency IM treatment method; (2) Drawings and/or schematics provided by the contractor and/or manufacturer of the approved technology; (3) A

  18. Problemer med å måle eksponering for passiv røyking blant barn

    Directory of Open Access Journals (Sweden)

    Per Nafstad m.fl.

    2009-10-01

    Full Text Available  SAMMENDRAGVanligvis måles eksponering for passiv røyking blant barn ved spørreskjemaopplysninger omforeldres røykevaner. Etter hvert som det blir mer oppmerksomhet om helseeffekter av passivrøyking, vil det kunne påvirke hvordan foreldre røyker og dermed også barns eksponering. Medhenvisning til innsamlede data om røykeeksponering i en kohort av Oslo-barn og fra en studie avbarn ved to helsestasjoner, diskuteres noen av de metodeproblemene en står overfor når en skal måleeksponering for passiv røyking i epidemiologiske studier. I disse studiene er barns eksponering forpassiv røyking målt ved spørreskjemaopplysninger og ved måling av hårnikotin og kotinin i urin.Det konkluderes med at det er usikkerhet om nøyaktigheten av eksisterende metoder for måling avpassiv røyking. Dette og manglende kunnskap om faktisk eksponeringsnivå kan føre til feilaktigestimering av helseeffekter av passiv røyking i en barnebefolkning.Nafstad P, Botten G, Magnus P. Problems in measuring environmental tobacco smoke exposurein children. Nor J Epidemiol 1995; 5 (2: 141-144.ENGLISH SUMMARYUsually environmental tobacco smoke exposure among children is measuered by questionnaires,recording parental smoking. As the adverse health effects of environmental tobacco smoke exposureare getting more known among the public, this is likely to influence the parents' way of smoking andby that their children's actual exposure. With references to findings in a cohort study of Oslochildren and a study of children attending two of Oslo’s health centers, some methodologicalproblems when measuring environmental tobacco smoke exposure in epidemiological studies arediscussed. The exposure in these studies is measured in questionnaires to the parents and aschildren's hair nicotine concentration and urine cotinine concentration. Furthermore, the paperdiscusses how the uncertainty in actual levels of exposure may lead to false estimates for the totalhealth impact of

  19. Mammal prey of the Barn Owl (Tyto alba) in Parque Luro Reserve, La Pampa, Argentina

    OpenAIRE

    1994-01-01

    Abstract The diet of the barn owl was studied through the analysis of pellets obtained in various sites within the Parque Luro reserve, located in an area of xerophyte Caldén forests. The study of 1241 prey items revealed a high dominance of the cricetid rodents Calomys sp., Akodon molinae and Eligmodontia typus, followed by other 8 species of rodents, one species of marsupial and undetermined birds a...

  20. Infektioner hos barn i förskola- gör utevistelse skillnad?

    DEFF Research Database (Denmark)

    Blennow, Margareta; Söderström, Margareta

    2009-01-01

    Under åren i förskolan har barn många infektioner, framförallt luftvägsinfektioner. Det finns indikationer på att allt fler föräldrar efterfrågar förskolor där barnen är utomhus hela dagen. Gör det barnen friskare? Den vetenskapliga litteraturen på området är sparsam. Resultaten är inte entydiga ...

  1. Optimization of Apparatus Design and Behavioral Measures for the Assessment of Visuo-Spatial Learning and Memory of Mice on the Barnes Maze

    Science.gov (United States)

    O'Leary, Timothy P.; Brown, Richard E.

    2013-01-01

    We have previously shown that apparatus design can affect visual-spatial cue use and memory performance of mice on the Barnes maze. The present experiment extends these findings by determining the optimal behavioral measures and test procedure for analyzing visuo-spatial learning and memory in three different Barnes maze designs. Male and female…

  2. An additional field method to sex adult Barn Swallows during the non-breeding season in Zambia: white spot length in the outer tail feather

    NARCIS (Netherlands)

    Duijns, S.; Dijk, van J.G.B.; Kraus, R.H.S.; Kerlen-Matema, A.C.; Brink, van den B.; Hooft, van W.F.

    2011-01-01

    Adult Barn Swallows Hirundo rustica exhibit strong sexual size dimorphism in the length of the outermost tail feathers, which are longer in males compared with females. This trait is traditionally used to sex adult Barn Swallows in the field. However, due to the wear and breakage of the tips of the

  3. An automatic system for the detection of dairy cows lying behaviour in free-stall barns

    Directory of Open Access Journals (Sweden)

    Simona M.C. Porto

    2013-09-01

    Full Text Available In this paper, a method for the automatic detection of dairy cow lying behaviour in free-stall barns is proposed. A computer visionbased system (CVBS composed of a video-recording system and a cow lying behaviour detector based on the Viola Jones algorithm was developed. The CVBS performance was tested in a head-to-head free stall barn. Two classifiers were implemented in the software component of the CVBS to obtain the cow lying behaviour detector. The CVBS was validated by comparing its detection results with those generated from visual recognition. This comparison allowed the following accuracy indices to be calculated: the branching factor (BF, the miss factor (MF, the sensitivity, and the quality percentage (QP. The MF value of approximately 0.09 showed that the CVBS missed one cow every 11 well detected cows. Conversely, the BF value of approximately 0.08 indicated that one false positive was detected every 13 well detected cows. The high value of approximately 0.92 obtained for the sensitivity index and that obtained for QP of about 0.85 revealed the ability of the proposed system to detect cows lying in the stalls.

  4. Visual pop-out in barn owls: Human-like behavior in the avian brain.

    Science.gov (United States)

    Orlowski, Julius; Beissel, Christian; Rohn, Friederike; Adato, Yair; Wagner, Hermann; Ben-Shahar, Ohad

    2015-01-01

    Visual pop-out is a phenomenon by which the latency to detect a target in a scene is independent of the number of other elements, the distractors. Pop-out is an effective visual-search guidance that occurs typically when the target is distinct in one feature from the distractors, thus facilitating fast detection of predators or prey. However, apart from studies on primates, pop-out has been examined in few species and demonstrated thus far in rats, archer fish, and pigeons only. To fill this gap, here we study pop-out in barn owls. These birds are a unique model system for such exploration because their lack of eye movements dictates visual behavior dominated by head movements. Head saccades and interspersed fixation periods can therefore be tracked and analyzed with a head-mounted wireless microcamera--the OwlCam. Using this methodology we confronted two owls with scenes containing search arrays of one target among varying numbers (15-63) of similar looking distractors. We tested targets distinct either by orientation (Experiment 1) or luminance contrast (Experiment 2). Search time and the number of saccades until the target was fixated remained largely independent of the number of distractors in both experiments. This suggests that barn owls can exhibit pop-out during visual search, thus expanding the group of species and brain structures that can cope with this fundamental visual behavior. The utility of our automatic analysis method is further discussed for other species and scientific questions.

  5. Fitness loss and germline mutations in barn swallows breeding in Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Ellegren, Hans; Lindgren, Gabriella; Primmer, C.R. [Swedish Univ. of Agricultural Sciences, Animal Breeding and Genetics Dept., Uppsala (Sweden); Moeller, A.P. [Universite Pierre et Marie Curie. Lab. d`Ecologie, Paris, 75 (France)

    1997-10-09

    The severe nuclear accident at Chernobyl in 1986 resulted in the worst reported accidental exposure of radioactive material to free-living organisms. Short-term effects on human populations inhabiting polluted areas include increased incidence of thyroid cancer, infant leukaemia, and congenital malformations in newborns. Two recent studies have reported, although with some controversy, that germline mutation rates were increased in humans and voles living close to Chernobyl, but little is known about the viability of the organisms affected. Here we report an increased frequency of partial albinism, a morphological aberration associated with a loss of fitness, among barn swallows, Hirundo rustica, breeding close to Chernobyl. Heretability estimates indicate that mutations causing albinism were at least partly of germline origin. Furthermore, evidence for an increased germline mutation rate was obtained from segregation analysis at two hypervariable microsatellite loci, indicating that mutation events in barn swallows from Chernobyl were two- to tenfold higher than in birds from control areas in Ukraine and Italy. (author).

  6. Food Barn for The Village Community To Strengthen Community Empowerment Program

    Directory of Open Access Journals (Sweden)

    Maulidyah Indira Hasmarini

    2016-12-01

    Full Text Available This study aimed to assess the achievement level of community empowerment in realizing food security. The result was expected to reveal a model of community empowerment, particularly farmer community institution as an attempt to attain food security. Survey was employed as the research method that involved the farmers (farmer groups as the members of Food Barn for the Village Community (Lumbung Pangan Masyarakat Desa/LPMD. Technique of rapid rural appraisal was selected in the form of quantitative and qualitative analysis. Preliminary survey in study area was carried out to obtain the characteristic and status of food security; and to mapping the potential and role of Lumbung Pangan Masyarakat Desa in the process of community empowerment. Subsequently, study and analysis was done based on the survey. The results demonstrated the active role of stakeholders (A-B-G-C was significant in supporting the farmer institution (food barn. The economic and social aspects were also evidenced to have important role in enhancing the farmer community empowerment. This model is called social engine for rural community and local institution, particularly to attain the regional food security.

  7. Testosterone, plumage colouration and extra-pair paternity in male North-American barn swallows.

    Directory of Open Access Journals (Sweden)

    Cas Eikenaar

    Full Text Available In most monogamous bird species, circulating testosterone concentration in males is elevated around the social female's fertile period. Variation in elevated testosterone concentrations among males may have a considerable impact on fitness. For example, testosterone implants enhance behaviours important for social and extra-pair mate choice. However, little is known about the relationship between natural male testosterone concentration and sexual selection. To investigate this relationship we measured testosterone concentration and sexual signals (ventral plumage colour and tail length, and determined within and extra-pair fertilization success in male North American barn swallows (Hirundo rustica erythrogaster. Dark rusty coloured males had higher testosterone concentrations than drab males. Extra-pair paternity was common (42% and 31% of young in 2009 and 2010, respectively, but neither within- nor extra-pair fertilization success was related to male testosterone concentration. Dark rusty males were less often cuckolded, but did not have higher extra-pair or total fertilization success than drab males. Tail length did not affect within- or extra-pair fertilization success. Our findings suggest that, in North American barn swallows, male testosterone concentration does not play a significant direct role in female mate choice and sexual selection. Possibly plumage colour co-varies with a male behavioural trait, such as aggressiveness, that reduces the chance of cuckoldry. This could also explain why dark males have higher testosterone concentrations than drab males.

  8. Non-Perturbative Asymptotic Improvement of Perturbation Theory and Mellin-Barnes Representation

    Directory of Open Access Journals (Sweden)

    Samuel Friot

    2010-10-01

    Full Text Available Using a method mixing Mellin-Barnes representation and Borel resummation we show how to obtain hyperasymptotic expansions from the (divergent formal power series which follow from the perturbative evaluation of arbitrary ''N-point'' functions for the simple case of zero-dimensional φ4 field theory. This hyperasymptotic improvement appears from an iterative procedure, based on inverse factorial expansions, and gives birth to interwoven non-perturbative partial sums whose coefficients are related to the perturbative ones by an interesting resurgence phenomenon. It is a non-perturbative improvement in the sense that, for some optimal truncations of the partial sums, the remainder at a given hyperasymptotic level is exponentially suppressed compared to the remainder at the preceding hyperasymptotic level. The Mellin-Barnes representation allows our results to be automatically valid for a wide range of the phase of the complex coupling constant, including Stokes lines. A numerical analysis is performed to emphasize the improved accuracy that this method allows to reach compared to the usual perturbative approach, and the importance of hyperasymptotic optimal truncation schemes.

  9. The maintenance of phenotypic divergence through sexual selection: An experimental study in barn swallows Hirundo rustica.

    Science.gov (United States)

    Safran, Rebecca J; Vortman, Yoni; Jenkins, Brittany R; Hubbard, Joanna K; Wilkins, Matthew R; Bradley, Rachel J; Lotem, Arnon

    2016-09-01

    Previous studies have shown that sexual signals can rapidly diverge among closely related species. However, we lack experimental studies to demonstrate that differences in trait-associated reproductive performance maintain sexual trait differences between closely related populations, in support for a role of sexual selection in speciation. Populations of Northern Hemisphere distributed barn swallows Hirundo rustica are closely related, yet differ in two plumage-based traits: ventral color and length of the outermost tail feathers (streamers). Here we provide experimental evidence that manipulations of these traits result in different reproductive consequences in two subspecies of barn swallow: (H. r. erythrogaster in North America and H. r. transitiva in the East Mediterranean). Experimental results in Colorado, USA, demonstrate that males with (1) darkened ventral coloration and (2) shortened streamers gained paternity between two successive reproductive bouts. In contrast, exaggeration of both traits improved reproductive performance within H. r. transitiva in Israel: males with a combination treatment of darkened ventral coloration and elongated streamers gained paternity between two successive reproductive bouts. Collectively, these experimental results fill an important gap in our understanding for how divergent sexual selection maintains phenotype differentiation in closely related populations, an important aspect of the speciation process.

  10. Head-related transfer functions of the barn owl: measurement and neural responses.

    Science.gov (United States)

    Keller, C H; Hartung, K; Takahashi, T T

    1998-04-01

    Sounds arriving at the eardrum are filtered by the external ear and associated structures in a frequency and direction specific manner. When convolved with the appropriate filters and presented to human listeners through headphones, broadband noises can be precisely localized to the corresponding position outside of the head (reviewed in Blauert, 1997). Such a 'virtual auditory space' can be a potentially powerful tool for neurophysiological and behavioral work in other species as well. We are developing a virtual auditory space for the barn owl, Tyto alba, a highly successful auditory predator that has become a well-established model for hearing research. We recorded catalogues of head-related transfer functions (HRTFs) from the frontal hemisphere of 12 barn owls and compared virtual and free sound fields acoustically and by their evoked neuronal responses. The inner ca. 1 cm of the ear canal was found to contribute little to the directionality of the HRTFs. HRTFs were recorded by inserting probetube microphones to within about 1 or 2 mm of the eardrum. We recorded HRTFs at frequencies between 2 and 11 kHz, which includes the frequencies most useful to the owl for sound localization (3-9 kHz; Konishi, 1973). Spectra of virtual sounds were within +/- 1 dB of amplitude and +/- 10 degrees of phase of the spectra of free field sounds measured near to the eardrum. The spatial pattern of responses obtained from neurons in the inferior colliculus were almost indistinguishable in response to virtual and to free field stimulation.

  11. Better-surviving barn swallow mothers produce more and better-surviving sons.

    Science.gov (United States)

    Romano, Andrea; Costanzo, Alessandra; Caprioli, Manuela; Parolini, Marco; Ambrosini, Roberto; Rubolini, Diego; Saino, Nicola

    2016-05-01

    Sex allocation theory predicts that parents are selected to bias their progeny sex ratio (SR) toward the sex that will benefit the most from parental quality. Because parental quality may differentially affect survival of sons and daughters, a pivotal test of the adaptive value of SR adjustment is whether parents overproduce offspring of the sex that accrues larger fitness advantages from high parental quality. However, this crucial test of the long-term fitness consequences of sex allocation decisions has seldom been performed. In this study of the barn swallow (Hirundo rustica), we showed a positive correlation between the proportion of sons and maternal annual survival. We then experimentally demonstrated that this association did not depend on the differential costs of rearing offspring of either sex. Finally, we showed that maternal lifespan positively predicted lifespan of sons but not of daughters. Because in barn swallows lifespan is a strong determinant of lifetime reproductive success, the results suggest that mothers overproduce offspring of the sex that benefits the most from maternal quality. Hence, irrespective of mechanisms causing the SR bias and mother-son covariation in lifespan, we provide strong evidence that sex allocation decisions of mothers can highly impact on their lifetime fitness.

  12. The Jellyfish hunter--Jack Barnes: a pioneer medical toxinologist in Australia.

    Science.gov (United States)

    Pearn, John; Fenner, Peter

    2006-12-01

    Dr Jack Handyside Barnes (1922-1985) was one of the small and elite group of Pacific marine toxinologists whose work was characterised by an uncompromising rugged persona, a focussed resolve to solve challenging problems of human clinical envenomation, and who conducted curiosity-driven research under conditions of scientific isolation. He was a pioneering advocate for the preservation of marine heritage, particularly that of the Great Barrier Reef. A former military commando who later became a general medical practitioner with extensive surgical and obstetric skills, in 1947 he was appointed the Medical Superintendent of Thursday Island in the Torres Strait. Later (from January 1953), he worked indefatigably as a general medical practitioner in Cairns, in tropical North Australia. For four decades (1945-1985), Jack Barnes undertook detailed laboratory, clinical and field research into invertebrate envenomation, particularly medusan toxinology. In 1960 he discovered the species responsible for the Irukandji syndrome, a small carybdeid named Carukia barnesi in his honour. He invented the research technique for the extraction of venom from the world's most venomous creature, the Pacific box Jellyfish, Chironex fleckeri. By 1960, he had published taxonomic details of nematocyst structure and clinical envenomation details consequent upon stings by Physalia, Cyanea, Chironex, Chiropsalmus and Carukia. This paper is a précis of the chronology of his life, contributions and influence.

  13. Laboratory-scale investigation of UV treatment of ammonia for livestock and poultry barn exhaust applications.

    Science.gov (United States)

    Rockafellow, Erin M; Koziel, Jacek A; Jenks, William S

    2012-01-01

    The feasibility of using deep ultraviolet (UV) treatment for abatement of ammonia (NH(3)) in livestock and poultry barn exhaust air was examined in a series of laboratory-scale experiments. These experiments simulated moving exhaust air through an irradiation chamber with variables of UV wavelength and dose, NH(3) concentrations, humidity, and presence of hydrogen sulfide (H(2)S). Ammonia, initially at relevant barn exhaust concentrations in air, was substantially or completely reduced by irradiation with 185 nm light. Reactions were monitored using chemiluminescence detection, gas chromatography with mass spectrometry detection, and Fourier transform infrared spectrometry, of which the latter was found to be the most informative and flexible. Detected nitrogen-containing products included N(2)O, NH(4)NO(3), and HNO(3). It was presumed that atomic oxygen is the primary photochemical product that begins the oxidative cascade. The data show that removal of NH(3) is plausible, but they highlight concerns over pollution swapping due to formation of ozone and N(2)O.

  14. The impact of uropygial gland secretions on mechanically induced wearing of barn owl and pigeon body feathers

    Science.gov (United States)

    Ott, Benjamin; Müsse, Annika; Wagner, Hermann

    2016-04-01

    Bird feathers are remarkable structures light but yet durable providing insulation and the ability of flight. Owls are highly specialized birds of prey, widely known for their ability to y silently which is enabled by (micro-) structural specializations of the feathers. The barn owl replaces feathers less frequently in comparison to other same sized birds like pigeons, indicating a much better resistance against material fatigue of these delicate microstructures. We used axisymmetric drop shape analysis (ADSA) of water drop contact angles as a non-destructive method of characterizing wearing processes in feathers. We hypothesized that feathers become more wettable when worn. We also investigated the impact of ethanol treatment in order to remove fatty residues of the uropygial gland secretions, barn owls and pigeons use for preening, on ageing processes. Ethanol treatment resulted in a slight, but significant increase of water repellency in barn owl but not in pigeon flight feathers. Our preliminary data also suggest that the uropygial gland secretions decelerate the wearing process of the feather keratin. We observed this effect in both species, however, it was more distinct for barn owl uropygial gland secretions. The results of this study, obtained by contact angle measurements used as a non-destructive evaluation method of material fatigue, yield insights into the material fatigue of feathers and the decelerating effect of uropygial gland secretions on wear on the other hand.

  15. Reverse correlation analysis of auditory-nerve fiber responses to broadband noise in a bird, the barn owl.

    Science.gov (United States)

    Fontaine, Bertrand; Köppl, Christine; Peña, Jose L

    2015-02-01

    While the barn owl has been extensively used as a model for sound localization and temporal coding, less is known about the mechanisms at its sensory organ, the basilar papilla (homologous to the mammalian cochlea). In this paper, we characterize, for the first time in the avian system, the auditory nerve fiber responses to broadband noise using reverse correlation. We use the derived impulse responses to study the processing of sounds in the cochlea of the barn owl. We characterize the frequency tuning, phase, instantaneous frequency, and relationship to input level of impulse responses. We show that, even features as complex as the phase dependence on input level, can still be consistent with simple linear filtering. Where possible, we compare our results with mammalian data. We identify salient differences between the barn owl and mammals, e.g., a much smaller frequency glide slope and a bimodal impulse response for the barn owl, and discuss what they might indicate about cochlear mechanics. While important for research on the avian auditory system, the results from this paper also allow us to examine hypotheses put forward for the mammalian cochlea.

  16. Effect of average diurnal barn airspace temperatures on prediction of their development during the day

    Directory of Open Access Journals (Sweden)

    Gustav Chládek

    2011-01-01

    Full Text Available A year-round (i.e. 365 days experiment was performed at the Mendel University Training Farm in Žabčice, Czech Republic (GPS 49°0’51.967”N and 16°36’14.614”E, the altitude 179 m with the aim to quantify the effect of the variation of average diurnal barn airspace temperatures on prediction of their changes during the day. Barn airspace temperatures were monitored daily in one-hour intervals and the recorded values were used for calculations of average diurnal temperatures. These were classified into 7 categories (i.e. below 0 °C; 0.1 to 5 °C; 5.1 to 10 °C; 10.1 to 15 °C; 15.1 to 20 °C; 20.1 to 25 °C and above 25 °C. Regarding this classification system, all differences between temperatures measured at identical hours but within various limits were statistically highly significant. The statistical analysis involved also the calculation of the third degree polynomial regression equations, which enabled to characterise the relationship between the temperature and the hour of measurement within the aforementioned categories of diurnal temperatures. Individual equations were markedly different and ranged from y = − 0.0019x3 + 0.0596x2 − 0.3797x − 1.2169 (for temperatures below 0 °C to y = − 0.0108x3 + 0.3297x2 − 1.9367x + 24.3931 (for temperatures above 25 °C. Correlation coefficients (r and coefficients of determination (R2 of these regression equations were generally very high and ranged from 0.872 to 0.976 and from 0.760 to 0.953, respectively. Regarding high values of both coefficients it can be concluded that the calculated equations enable a good and reliable prediction of the diurnal development of barn airspace temperatures.

  17. AMBRE—a Mathematica package for the construction of Mellin Barnes representations for Feynman integrals

    Science.gov (United States)

    Gluza, J.; Kajda, K.; Riemann, T.

    2007-12-01

    The Mathematica toolkit AMBRE derives Mellin-Barnes (MB) representations for Feynman integrals in d=4-2ɛ dimensions. It may be applied for tadpoles as well as for multi-leg multi-loop scalar and tensor integrals. The package uses a loop-by-loop approach and aims at lowest dimensions of the final MB representations. The present version works fine for planar Feynman diagrams. The output may be further processed by the package MB for the determination of its singularity structure in ɛ. The AMBRE package contains various sample applications for Feynman integrals with up to six external particles and up to four loops. Program summaryProgram title:AMBRE Catalogue identifier:ADZR_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZR_v1_0.html Program obtainable from:CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions:standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.:21 387 No. of bytes in distributed program, including test data, etc.:100 004 Distribution format:tar.gz Programming language:MATHEMATICA v.5.0 and later versions Computer:all Operating system:all RAM:sufficient for a typical installation of MATHEMATICA Classification:5; 11.1 External routines:The examples in the package use: MB.m [M. Czakon, Comput. Phys. Commun. 175 (2006) 559 (CPC Cat. Id. ADYG)], for expansions in ɛ; CUBA [T. Hahn, Comput. Phys. Commun. 168 (2005) 78 (CPC Cat. Id. ADVH)], for numerical evaluation of multidimensional integrals; CERNlib [CERN Program Library, http://cernlib.web.cern.ch/cernlib/], for the implementation of Γ and Ψ functions in Fortran. Nature of problem:Derivation of a representation for a Feynman diagram with L loops and N internal lines in d dimensions by Mellin-Barnes integrals; the subsequent evaluation, after an analytical continuation in ɛ=(4-d)/2, has to be done with other packages. Solution method:Introduction of N Feynman parameters x

  18. Reactor Physics Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Raedt, C

    2000-07-01

    The Reactor Physics and Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis on reactor fuel. This expertise is applied within the Reactor Physics and MYRRHA Research Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments. Progress and achievements in 1999 in the following areas are reported on: (1) investigations on the use of military plutonium in commercial power reactors; (2) neutron and gamma calculations performed for BR-2 and for other reactors; (3) the updating of neutron and gamma cross-section libraries; (4) the implementation of reactor codes; (6) the management of the UNIX workstations; and (6) fuel cycle studies.

  19. Avian wing geometry and kinematics of a free-flying barn owl in flapping flight

    Science.gov (United States)

    Wolf, Thomas; Konrath, Robert

    2015-02-01

    This paper presents results of high-resolution three-dimensional wing shape measurements performed on free-flying barn owls in flapping flight. The applied measurement technique is introduced together with a moving camera set-up, allowing for an investigation of the free flapping flight of birds with high spatial and temporal resolution. Based on the three-dimensional surface data, a methodology for parameterizing the wing profile along with wing kinematics during flapping flight has been developed. This allowed a description of the spanwise varying kinematics and aerodynamic parameters (e.g. effective angles of attack, camber, thickness) of the wing in dependence on the flapping phase. The results are discussed in detail using the data of a single flight, whereas a comparison of some kinematic parameters obtained from different flights is given too.

  20. Independence of echo-threshold and echo-delay in the barn owl.

    Directory of Open Access Journals (Sweden)

    Brian S Nelson

    Full Text Available Despite their prevalence in nature, echoes are not perceived as events separate from the sounds arriving directly from an active source, until the echo's delay is long. We measured the head-saccades of barn owls and the responses of neurons in their auditory space-maps while presenting a long duration noise-burst and a simulated echo. Under this paradigm, there were two possible stimulus segments that could potentially signal the location of the echo. One was at the onset of the echo; the other, after the offset of the direct (leading sound, when only the echo was present. By lengthening the echo's duration, independently of its delay, spikes and saccades were evoked by the source of the echo even at delays that normally evoked saccades to only the direct source. An echo's location thus appears to be signaled by the neural response evoked after the offset of the direct sound.

  1. Personal Geographies: Poetic Lineage of American Poets Elizabeth Coatsworth and Kate Barnes

    Directory of Open Access Journals (Sweden)

    Ellen Maureen Taylor

    2016-12-01

    Full Text Available This paper examines the relationship between two 20th-century American poets, Elizabeth Coatsworth and her daughter, Kate Barnes. Both women mined their physical and personal geographies to create their work; both labored in the shadows of domineering literary husbands. Elizabeth’s early poetry is economical in language, following literary conventions shaped by Eastern poets and Imagists of her era. Kate’s work echoes her mother’s painterly eye, yet is informed by the feminist poetry of her generation. Their dynamic relationship as mother and daughter, both struggling with service to the prevailing Western patriarchy, duties of domestication and docility, also inform their writing. This paper draws from Coatsworth’s poems, essays, and memoir, and Barnes’ poems, interviews, and epistolary archives, which shed light on her relationship with her renowned mother.

  2. Cassia spectabilis (DC) Irwin et Barn: a promising traditional herb in health improvement.

    Science.gov (United States)

    Jothy, Subramanion L; Torey, Angeline; Darah, Ibrahim; Choong, Yee Siew; Saravanan, Dharmaraj; Chen, Yeng; Latha, Lachimanan Yoga; Deivanai, Subramanian; Sasidharan, Sreenivasan

    2012-08-29

    The genus Cassia, comprising about 600 species widely distributed worldwide is well known for its diverse biological and pharmacological properties. Cassia spectabilis (sin Senna spectabilis) (DC) Irwin et Barn (Fabaceae) is widely grown as an ornamental plant in tropical and subtropical areas. C. spectabilis has been commonly used in traditional medicine for many years. Information in the biomedical literature has indicated the presence of a variety of medicinally-important chemical constituents in C. spectabilis. Pharmacological studies by various groups of investigators have shown that C. spectabilis possesses significant biological activity, such as antibacterial, antibiofilm, antifungal and antioxidant properties. Beside this, toxicity studies of this plant have revealed no toxic effect on mice. In view of the immense medicinal importance of C. spectabilis, this review aimed at compiling all currently available information on C. spectabilis’s botany, phytochemistry, pharmacology, and mechanism of actions, toxicology and its ethnomedicinal uses.

  3. The GEMPAK Barnes interactive objective map analysis scheme. [General Meteorological Software Package

    Science.gov (United States)

    Koch, S. E.; Kocin, P. J.; Desjardins, M.

    1983-01-01

    The analysis scheme and meteorological applications of the GEMPAK data analysis and display software system developed by NASA are described. The program was devised to permit objective, versatile, and practical analysis of satellite meteorological data using a minicomputer and a display system with graphics capability. A data area can be selected within the data file for the globe, and data-sparse regions can be avoided. Distances between observations and the nearest observation points are calculated in order to avoid errors when determining synoptic weather conditions. The Barnes (1973) successive correction method is employed to restore the amplitude of small yet resolvable wavelengths suppressed in an initial filtering pass. The rms deviation is then calculated in relation to available measured data. Examples are provided of treatment of VISSR data from the GOES satellite and a study of the impact of incorrect cloud height data on synoptic weather field analysis.

  4. Monaural occlusion alters sound localization during a sensitive period in the barn owl.

    Science.gov (United States)

    Knudsen, E I; Esterly, S D; Knudsen, P F

    1984-04-01

    Sound localization was disrupted in young barn owls by chronically plugging one ear. Owls that were younger than 8 weeks of age at the time of ear plugging recovered normal localization accuracy while plugged, whereas those that were older than 8 weeks at the time of ear plugging did not. The end of the sensitive period for the adjustment of sound localization accuracy coincides with the maturation of the head and ears, suggesting that the exposure of the auditory system to stable, adult-like acoustic cues could play a role in bringing the sensitive period to a close. The results demonstrate that, early in development, associations between auditory cues and locations in space can be altered by experience.

  5. Commissural connections mediate inhibition for the computation of interaural level difference in the barn owl.

    Science.gov (United States)

    Takahashi, T T; Keller, C H

    1992-02-01

    In the barn owl (Tyto alba), the posterior nucleus of the ventral lateral lemniscus (VLVp) is the first site of binaural convergence in the pathway that processes interaural level difference (ILD), an important sound-localization cue. The neurons of VLVp are sensitive to ILD because of an excitatory input from the contralateral ear and an inhibitory input from the ipsilateral ear. A previously described projection from the contralateral cochlear nucleus, can account for the excitation. The present study addresses the source of the inhibitory input. We demonstrate with standard axonal transport methods that the left and right VLVps are interconnected via fibers of the commissure of Probst. We further show that the anesthetization of one VLVp renders ineffective the inhibition that is normally evoked by stimulation of the ipsilateral ear. Thus, one cochlear nucleus (driven by the ipsilateral ear) appears to provide inhibition to the ipsilateral VLVp by exciting commissurally-projecting inhibitory neurons in the contralateral VLVp.

  6. El museo y la enciclopedia: Lecturas cruzadas de Borges y Barnes

    Directory of Open Access Journals (Sweden)

    Leticia Moneta

    2014-01-01

    Full Text Available Taking in consideration the intertextual and biographical influence of the works of Jorge Luis Borges on the works of Julian Barnes, this article seeks to focus on certain borgian traces that speak of the status of literature in the present time. Starting with the image of the “museum and the encyclopedia” we can read Borges from a barnesian point of view and viceversa, while insisting in the relativity of any kind of order and classification. We shall start with the essential distrust that both authors show towards language. No one can deny that in the literary and critic landscape of our time Borges is a difficult character to overcome or ignore which we will use as a reading and writing mechanism.

  7. Attrition reactor system

    Science.gov (United States)

    Scott, Charles D.; Davison, Brian H.

    1993-01-01

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  8. Fan cooling of the resting area in a free stalls dairy barn.

    Science.gov (United States)

    Calegari, Ferdinando; Calamari, Luigi; Frazzi, Ermes

    2014-08-01

    This summer study evaluated the effect of providing additional fans (cooling) in the resting area within a free-stall dairy barn that had fans and sprinklers in the feeding area and paddock availability. Thirty cows were divided into two homogenous groups and kept in two pens: one had the resting area equipped with two fans (FAN) while no fans were added to the other resting area (CON). Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and milk pH traits were recorded. Time budgeting and the behaviour of the cows (time spent in the feeding area, standing and lying in other areas) were also recorded using digital video technology. Two slight-to-moderate heat waves were observed. During the hottest period the daily maximum temperature recorded was 33.5 °C and the daily maximum THI was 81.6. During this period, the BR and RT increased only slightly in both groups, with lower BR (n.s.) in FAN compared with CON. Milk yield was better maintained (n.s.) in FAN compared with CON during the hottest period. The FAN cows showed a greater (Pfree stalls (9.5 and 8.6 h/day in FAN and CON, respectively), whereas CON cows made greater (P<0.05) use of the paddock during evening and late evening hours. Consequently, the total daily lying time was 13.5 h/day in both groups. In conclusion, the results suggest that using fans in the resting area improves cow comfort, which increases use of the resting area. The lying time results also suggest that the benefits of providing ventilation in the resting area might be more evident in barns where there is no paddock.

  9. Coding of sound pressure level in the barn owl's auditory nerve.

    Science.gov (United States)

    Köppl, C; Yates, G

    1999-11-01

    Rate-intensity functions, i.e., the relation between discharge rate and sound pressure level, were recorded from single auditory nerve fibers in the barn owl. Differences in sound pressure level between the owl's two ears are known to be an important cue in sound localization. One objective was therefore to quantify the discharge rates of auditory nerve fibers, as a basis for higher-order processing of sound pressure level. The second aim was to investigate the rate-intensity functions for cues to the underlying cochlear mechanisms, using a model developed in mammals. Rate-intensity functions at the most sensitive frequency mostly showed a well-defined breakpoint between an initial steep segment and a progressively flattening segment. This shape has, in mammals, been convincingly traced to a compressive nonlinearity in the cochlear mechanics, which in turn is a reflection of the cochlear amplifier enhancing low-level stimuli. The similarity of the rate-intensity functions of the barn owl is thus further evidence for a similar mechanism in birds. An interesting difference from mammalian data was that this compressive nonlinearity was not shared among fibers of similar characteristic frequency, suggesting a different mechanism with a more locally differentiated operation than in mammals. In all fibers, the steepest change in discharge rate with rising sound pressure level occurred within 10-20 dB of their respective thresholds. Because the range of neural thresholds at any one characteristic frequency is small in the owl, auditory nerve fibers were collectively most sensitive for changes in sound pressure level within approximately 30 dB of the best thresholds. Fibers most sensitive to high frequencies (>6-7 kHz) showed a smaller increase of rate above spontaneous discharge rate than did lower-frequency fibers.

  10. Characterization of Prototheca zopfii Genotypes Isolated from Cases of Bovine Mastitis and Cow Barns in China.

    Science.gov (United States)

    Shahid, Muhammad; Ali, Tariq; Zhang, Limei; Hou, Rongguang; Zhang, Shiyao; Ding, Laidi; Han, Dandan; Deng, Zhaoju; Rahman, Abdur; Han, Bo

    2016-04-01

    Protothecal mastitis, caused mostly by Prototheca zopfii (P. zopfii), is increasing in dairy herds and is being reported globally. The present study was aimed at studying the epidemiology of mastitis and at molecular characterization of P. zopfii isolates from dairy herds and their surroundings in three provinces of China using microbiological, biochemical and molecular methods, and antibiotic susceptibility tests. Samples from milk (n = 620) of mastitic cows and their barns sources (n = 410) including feces, feed, bedding materials and drinking water were analyzed. Among other pathogens recovered from mastitic milk, 84 (13.5%) of the isolates were identified as P. zopfii. All of the P. zopfii isolates recovered from milk were recognized as genotype 2, whereas 58 (73.4%) and 21 (26.6%) isolates from environmental sources were found to be P. zopfii genotypes 1 and 2, respectively. The isolates were susceptible to some antibiotics and antifungal agents, including amikacin (78.1%), streptomycin (58.5%), gentamicin (17.8%), amphotericin B (68.6%) and nystatin (64.4%). Additionally, the two genotypes displayed versatile patterns of susceptibility to different antimicrobials agents. Phylogeny of the genotypes on the basis of 18S SSU rDNA and 28S SSU rDNA was also investigated. The isolates of the two genotypes separated into different clades, and no interrelationship was observed among these as shown by phylogenetic analysis. The genotype 1 isolates from cow barn sources were non-pathogenic and may not present any risk of mastitis. We conclude that P. zopfii genotype 2 might play an important role in bovine mastitis in China.

  11. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hiroto

    1995-02-07

    A reactor container of the present invention has a structure that the reactor container is entirely at the same temperature as that at the inlet of the reactor and, a hot pool is incorporated therein, and the reactor container has is entirely at the same temperature and has substantially uniform temperature follow-up property transiently. Namely, if the temperature at the inlet of the reactor core changes, the temperature of the entire reactor container changes following this change, but no great temperature gradient is caused in the axial direction and no great heat stresses due to axial temperature distribution is caused. Occurrence of thermal stresses caused by the axial temperature distribution can be suppressed to improve the reliability of the reactor container. In addition, since the laying of the reactor inlet pipelines over the inside of the reactor is eliminated, the reactor container is made compact and the heat shielding structures above the reactor and a protection structure of container walls are simplified. Further, secondary coolants are filled to the outside of the reactor container to simplify the shieldings. The combined effects described above can improve economical property and reliability. (N.H.).

  12. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  13. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  14. Morphometric characterisation of wing feathers of the barn owl Tyto alba pratincola and the pigeon Columba livia

    Directory of Open Access Journals (Sweden)

    Klaas Michael

    2007-11-01

    Full Text Available Abstract Background Owls are known for their silent flight. Even though there is some information available on the mechanisms that lead to a reduction of noise emission, neither the morphological basis, nor the biological mechanisms of the owl's silent flight are known. Therefore, we have initiated a systematic analysis of wing morphology in both a specialist, the barn owl, and a generalist, the pigeon. This report presents a comparison between the feathers of the barn owl and the pigeon and emphasise the specific characteristics of the owl's feathers on macroscopic and microscopic level. An understanding of the features and mechanisms underlying this silent flight might eventually be employed for aerodynamic purposes and lead to a new wing design in modern aircrafts. Results A variety of different feathers (six remiges and six coverts, taken from several specimen in either species, were investigated. Quantitative analysis of digital images and scanning electron microscopy were used for a morphometric characterisation. Although both species have comparable body weights, barn owl feathers were in general larger than pigeon feathers. For both species, the depth and the area of the outer vanes of the remiges were typically smaller than those of the inner vanes. This difference was more pronounced in the barn owl than in the pigeon. Owl feathers also had lesser radiates, longer pennula, and were more translucent than pigeon feathers. The two species achieved smooth edges and regular surfaces of the vanes by different construction principles: while the angles of attachment to the rachis and the length of the barbs was nearly constant for the barn owl, these parameters varied in the pigeon. We also present a quantitative description of several characteristic features of barn owl feathers, e.g., the serrations at the leading edge of the wing, the fringes at the edges of each feather, and the velvet-like dorsal surface. Conclusion The quantitative

  15. Starch gel and cellulose acetate electrophoretic analysis of allozyme frequencies in barn swallow (Hirundo rustica) populations at a dioxin contaminated site in northern Louisiana

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study compared the genetic variability of Louisiana barn swallows at a dioxin-contaminated wetland to two reference populations. Allozyme frequencies,...

  16. Spinning fluids reactor

    Science.gov (United States)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  17. Reactor Vessel Surveillance Program for Advanced Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyeong-Hoon; Kim, Tae-Wan; Lee, Gyu-Mahn; Kim, Jong-Wook; Park, Keun-Bae; Kim, Keung-Koo

    2008-10-15

    This report provides the design requirements of an integral type reactor vessel surveillance program for an integral type reactor in accordance with the requirements of Korean MEST (Ministry of Education, Science and Technology Development) Notice 2008-18. This report covers the requirements for the design of surveillance capsule assemblies including their test specimens, test block materials, handling tools, and monitors of the surveillance capsule neutron fluence and temperature. In addition, this report provides design requirements for the program for irradiation surveillance of reactor vessel materials, a layout of specimens and monitors in the surveillance capsule, procedures of installation and retrieval of the surveillance capsule assemblies, and the layout of the surveillance capsule assemblies in the reactor.

  18. A Stiff Man-Child Walking: Derrida’s Economy of Secrecy and Faulkner’s “Barn Burning”

    Directory of Open Access Journals (Sweden)

    Michael Wainwright

    2011-12-01

    Full Text Available Working from Jacques Derrida’s contentions about secrecy and authorial responsibility, and paying brief but specific attention to Charles Baudelaire’s “La fausse monnaie” (1869, as suggested by Derridean concerns over capitalist economics, this article studies the manner in which the inviolable and conditional secrets of William Faulkner’s “Barn Burning” (1938 reveal the poststructural tendencies avant la lettre of this leading American modernist.  While Faulkner scholars have focused on the ambivalent language and metaphors deployed in this short story, they have not formerly traced the manner in which “Barn Burning” incites a sense of deconstructive criticism, and have thereby failed to acknowledge Faulkner’s attendant authorial irresponsibility.  This article redresses this critical imbalance.

  19. Early auditory experience aligns the auditory map of space in the optic tectum of the barn owl.

    Science.gov (United States)

    Knudsen, E I

    1983-11-25

    Auditory and visual space are mapped in the optic tectum of the barn owl. Normally, these maps of space are in close mutual alignment. Ear plugs inserted unilaterally in young barn owls disrupted the binaural cues that constitute the basis of the auditory map. Yet when recordings were made from the tecta of these birds as adults, the auditory and visual maps were in register. When the ear plugs were removed from these adult birds and binaural balance was restored, the auditory maps were shifted substantially relative to the visual maps and relative to the physical borders of the tecta. These results demonstrate that the neural connectivity that gives rise to the auditory map of space in the optic tectum can be modified by experience in such a way that spatial alignment between sensory modalities is maintained.

  20. Effects of triticale-based diets on finishing pig performance and pork quality in deep-bedded hoop barns.

    Science.gov (United States)

    Sullivan, Zebblin M; Honeyman, Mark S; Gibson, Lance R; Prusa, Ken J

    2007-07-01

    Effects of triticale diets on pig performance and pork quality were evaluated in summer and winter. Diets were: corn-soy, 40% triticale, or 80% triticale. Pigs (72kg) were fed 49d. Loins were evaluated for meat and fat quality and sensory evaluation. Average daily gain decreased as triticale inclusion increased (Ptriticale had least gain:feed ratio (Ptriticale diet had smallest loin muscle area (PTriticale fed to pigs in hoop barns slightly decreased growth without compromising pork quality.

  1. Barn Owl pellets (Aves: Tyto furcata) reveal a higher mammalian richness in the Restinga de Jurubatiba National Park, Southeastern Brazil

    OpenAIRE

    2015-01-01

    The northern coast of the state of Rio de Janeiro harbors the largest coastal sandy plains (restingas) of southeastern Brazil, severely threatened due to recent human occupation. In this context, mammal inventories becomes urgent to support biodiversity conservation and management policies. This paper aims to update the knowledge on the mammalian species richness of Restinga de Jurubatiba National Park by analyzing pellets of the Barn owl Tyto furcata. The analyses of 4745 mammalian bone frag...

  2. Muscular Arrangement and Muscle Attachment Sites in the Cervical Region of the American Barn Owl (Tyto furcata pratincola)

    OpenAIRE

    2015-01-01

    Owls have the largest head rotation capability amongst vertebrates. Anatomical knowledge of the cervical region is needed to understand the mechanics of these extreme head movements. While data on the morphology of the cervical vertebrae of the barn owl have been provided, this study is aimed to provide an extensive description of the muscle arrangement and the attachment sites of the muscles on the owl's head-neck region. The major cervical muscles were identified by gross dissection of cada...

  3. DNA damage in barn swallows (Hirundo rustica) from the Chernobyl region detected by use of the comet assay.

    Science.gov (United States)

    Bonisoli-Alquati, Andrea; Voris, Andrew; Mousseau, Timothy A; Møller, Anders Pape; Saino, Nicola; Wyatt, Michael D

    2010-04-01

    We investigated levels of DNA damage in blood cells of barn swallows (Hirundo rustica) inhabiting the Chernobyl region to evaluate whether chronic exposure to low-level radioactive contamination continues to induce genetic damage in free-living populations of animals. Blood samples were obtained from barn swallows collected at sites with different background levels of radiation, including a relatively uncontaminated area. The extent of DNA damage was evaluated using the alkaline (pH=12.1) comet assay, a robust and sensitive electrophoresis-based technique widely employed in research ranging from biomonitoring to clinical studies. We found that levels of DNA damage, as indexed by the extent of DNA migration, were increased in barn swallows living in areas surrounding Chernobyl when compared to swallows sampled at low-level sites. The results we obtained are consistent with previous findings on this same species, which showed that swallows breeding in areas heavily contaminated with radionuclides have increased mutation rates, higher oxidative stress and incidence of morphological aberrations and tumors. Overall, these results indicate that chronic exposure to radioactive contaminants, even 20years after the accident at the Chernobyl nuclear power plant, continues to induce DNA damage in cells of free-living animals.

  4. Characterization of bioaerosols from dairy barns: reconstructing the puzzle of occupational respiratory diseases by using molecular approaches.

    Science.gov (United States)

    Blais Lecours, Pascale; Veillette, Marc; Marsolais, David; Duchaine, Caroline

    2012-05-01

    To understand the etiology of exposure-related diseases and to establish standards for reducing the risks associated with working in contaminated environments, the exact nature of the bioaerosol components must be defined. Molecular biology tools were used to evaluate airborne bacterial and, for the first time, archaeal content of dairy barns. Three air samplers were tested in each of the 13 barns sampled. Up to 10(6) archaeal and 10(8) bacterial 16S rRNA genes per m(3) of air were detected. Archaeal methanogens, mainly Methanobrevibacter species, were represented. Saccharopolyspora rectivirgula, the causative agent of farmer's lung, was quantified to up to 10(7) 16S rRNA genes per m(3) of air. In addition, a wide variety of bacterial agents were present in our air samples within the high airborne bioaerosol concentration range. Despite recommendations regarding hay preservation and baling conditions, farmers still develop an S. rectivirgula-specific humoral immune response, suggesting intense and continuous exposure. Our results demonstrate the complexity of bioaerosol components in dairy barns which could play a role in occupational respiratory diseases.

  5. Evolutionary divergence in sexual signals: Insights from within and among barn swallow populations

    Science.gov (United States)

    Wilkins, Matthew Reed

    A wealth of studies across diverse animal groups indicate the importance of sexual selection in shaping phenotypes within and across breeding populations. In recent decades, much research has focused on how divergent sexual selection pressures among populations may lead to speciation. For my first dissertation chapter, I performed a literature review on the causes and consequences of evolutionary divergence in acoustic signals and developed the acoustic window conceptual framework for understanding the contributions of selection, genetic drift, and evolutionary constraint to signal divergence. Further, I found that sexual selection explains acoustic differences between recently diverged populations of the best-studied taxa. However, the relative contributions of ecological selection, sexual selection, and drift to acoustic divergence have not typically been considered within the same study systems. The remainder of my dissertation used the Northern Hemisphere-distributed barn swallow ( Hirundo rustica) species complex as a model system to study sender-receiver dynamics, intra- and intersexual selection pressures, and visual and acoustic signal interactions at the local scale, and signal divergence across populations at the global scale. From song recordings taken across 19 sampling sites, spanning five of six described subspecies, I demonstrated considerable conservation in song structure. However, temporal traits were highly divergent across subspecies, and in particular, the speed of the terminal trill of songs. In a detailed study of the multimodal communication system of the barn swallow (including visual and acoustic traits), I demonstrated that males and females use different types of signals to mediate competition and mate choice. One of the only exceptions to this rule was trill rate, which was also implicated in song divergence across populations. In order to test the function of trill rate in communication, I performed a two-year playback study within the

  6. Auditory tuning for spatial cues in the barn owl basal ganglia.

    Science.gov (United States)

    Cohen, Y E; Knudsen, E I

    1994-07-01

    1. The basal ganglia are known to contribute to spatially guided behavior. In this study, we investigated the auditory response properties of neurons in the barn owl paleostriatum augmentum (PA), the homologue of the mammalian striatum. The data suggest that the barn owl PA is specialized to process spatial cues and, like the mammalian striatum, is involved in spatial behavior. 2. Single- and multiunit sites were recorded extracellularly in ketamine-anesthetized owls. Spatial receptive fields were measured with a free-field sound source, and tuning for frequency and interaural differences in timing (ITD) and level (ILD) was assessed using digitally synthesized dichotic stimuli. 3. Spatial receptive fields measured at nine multiunit sites were tuned to restricted regions of space: tuning widths at half-maximum response averaged 22 +/- 9.6 degrees (mean +/- SD) in azimuth and 54 +/- 22 degrees in elevation. 4. PA sites responded strongly to broadband sounds. When frequency tuning could be measured (n = 145/201 sites), tuning was broad, averaging 2.7 kHz at half-maximum response, and tended to be centered near the high end of the owl's audible range. The mean best frequency was 6.2 kHz. 5. All PA sites (n = 201) were selective for both ITD and ILD. ITD tuning curves typically exhibited a single, large "primary" peak and often smaller, "secondary" peaks at ITDs ipsilateral and/or contralateral to the primary peak. Three indices quantified the selectivity of PA sites for ITD. The first index, which was the percent difference between the minimum and maximum response as a function of ITD, averaged 100 +/- 29%. The second index, which represented the size of the largest secondary peak relative to that of the primary peak, averaged 49 +/- 23%. The third index, which was the width of the primary ITD peak at half-maximum response, averaged only 66 +/- 35 microseconds. 6. The majority (96%; n = 192/201) of PA sites were tuned to a single "best" value of ILD. The widths of ILD

  7. SNTP program reactor design

    Science.gov (United States)

    Walton, Lewis A.; Sapyta, Joseph J.

    1993-06-01

    The Space Nuclear Thermal Propulsion (SNTP) program is evaluating the feasibility of a particle bed reactor for a high-performance nuclear thermal rocket engine. Reactors operating between 500 MW and 2,000 MW will produce engine thrusts ranging from 20,000 pounds to 80,000 pounds. The optimum reactor arrangement depends on the power level desired and the intended application. The key components of the reactor have been developed and are being tested. Flow-to-power matching considerations dominate the thermal-hydraulic design of the reactor. Optimal propellant management during decay heat cooling requires a three-pronged approach. Adequate computational methods exist to perform the neutronics analysis of the reactor core. These methods have been benchmarked to critical experiment data.

  8. Hybrid reactors. [Fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  10. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Mitsuru

    1997-04-04

    An LMFBR type reactor comprises a plurality of reactor cores in a reactor container. Namely, a plurality of pot containing vessels are disposed in the reactor vessel and a plurality of reactor cores are formed in a state where an integrated-type fuel assembly is each inserted to a pot, and a coolant pipeline is connected to each of the pot containing-vessel to cool the reactor core respectively. When fuels are exchanged, the integrated-type fuel assembly is taken out together with the pot from the reactor vessel in a state where the integrated-type fuel assembly is immersed in the coolants in the pot as it is. Accordingly, coolants are supplied to each of the pot containing-vessel connected with the coolant pipeline and circulate while cooling the integrated-type fuel assembly for every pot. Then, when the fuels are exchanged, the integrated type fuel assembly is taken out to the outside of the reactor together with the pot by taking up the pot from the pot-containing vessel. Then, neutron economy is improved to thereby improve reactor power and the breeding ratio. (N.H.)

  11. INVAP's Research Reactor Designs

    Directory of Open Access Journals (Sweden)

    Eduardo Villarino

    2011-01-01

    Full Text Available INVAP, an Argentine company founded more than three decades ago, is today recognized as one of the leaders within the research reactor industry. INVAP has participated in several projects covering a wide range of facilities, designed in accordance with the requirements of our different clients. For complying with these requirements, INVAP developed special skills and capabilities to deal with different fuel assemblies, different core cooling systems, and different reactor layouts. This paper summarizes the general features and utilization of several INVAP research reactor designs, from subcritical and critical assemblies to high-power reactors.

  12. Multi purpose research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Raina, V.K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)]. E-mail: vkrain@magnum.barc.ernet.in; Sasidharan, K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sengupta, Samiran [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Singh, Tej [Research Reactor Services Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2006-04-15

    At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research and development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.

  13. Efficient Implementation of the Barnes-Hut Octree Algorithm for Monte Carlo Simulations of Charged Systems

    CERN Document Server

    Gan, Zecheng

    2013-01-01

    Computer simulation with Monte Carlo is an important tool to investigate the function and equilibrium properties of many systems with biological and soft matter materials solvable in solvents. The appropriate treatment of long-range electrostatic interaction is essential for these charged systems, but remains a challenging problem for large-scale simulations. We have developed an efficient Barnes-Hut treecode algorithm for electrostatic evaluation in Monte Carlo simulations of Coulomb many-body systems. The algorithm is based on a divide-and-conquer strategy and fast update of the octree data structure in each trial move through a local adjustment procedure. We test the accuracy of the tree algorithm, and use it to computer simulations of electric double layer near a spherical interface. It has been shown that the computational cost of the Monte Carlo method with treecode acceleration scales as $\\log N$ in each move. For a typical system with ten thousand particles, by using the new algorithm, the speed has b...

  14. “And all the windows, great and small”. Finestre in Nightwood di Djuna Barnes

    Directory of Open Access Journals (Sweden)

    Francesca Chiappini

    2015-01-01

    Full Text Available As a recurring subject and powerful symbol, the window dominates the female literary and artistic imagery of the twentieth century. It has been developed into mirror, photograph or painting, according to the writer’s needs, yet the basic shape of the frame is always retraceable. Among late modernist and postmodernist women writers, Djuna Barnes explores in detail the structural resources of this literary device. Although she already understands the potential of the frame in her early career as a journalist, she mostly challenges its extents of versatility in Nightwood (1936. Its crucial moments – either flashing epiphanies or missed catharsis – involve the physical presence of a window, which embodies a powerful narrative agent; more than mere symbol, it is active at several levels. Thematically, doors and windows, pictures and mirrors, play an important cohesive role. At a deeper stage of analysis, the structure of the novel itself is shored up by doors and windows, since the setting is essentially organized into indoors and outdoors scenes; windows and doors allow the characters to move between these two dimensions. On the metaphorical level, windows and doors represent a communicative channel; a room-door opening suggests the access to one’s inner life, whereas a shut window denies any chance of dialogue. However, all the characters seem to be too absorbed by their obsessions to realize such communicative potential, and rather meander uselessly in their mental frames.

  15. In vivo Recordings from Low-Frequency Nucleus Laminaris in the Barn Owl.

    Science.gov (United States)

    Palanca-Castan, Nicolas; Köppl, Christine

    2015-01-01

    Localization of sound sources relies on 2 main binaural cues: interaural time differences (ITD) and interaural level differences. ITD computing is first carried out in tonotopically organized areas of the brainstem nucleus laminaris (NL) in birds and the medial superior olive (MSO) in mammals. The specific way in which ITD are derived was long assumed to conform to a delay line model in which arrays of systematically arranged cells create a representation of auditory space, with different cells responding maximally to specific ITD. This model conforms in many details to the particular case of the high-frequency regions (above 3 kHz) in the barn owl NL. However, data from recent studies in mammals are not consistent with a delay line model. A new model has been suggested in which neurons are not topographically arranged with respect to ITD and coding occurs through assessment of the overall response of 2 large neuron populations – 1 in each brainstem hemisphere. Currently available data comprise mainly low-frequency (owl and compare it to data from other avian and mammalian studies. Our data are consistent with a delay line model, so differences between ITD processing systems are more likely to have originated through divergent evolution of different vertebrate groups.

  16. Hunting Increases Phosphorylation of Calcium/Calmodulin-Dependent Protein Kinase Type II in Adult Barn Owls

    Directory of Open Access Journals (Sweden)

    Grant S. Nichols

    2015-01-01

    Full Text Available Juvenile barn owls readily adapt to prismatic spectacles, whereas adult owls living under standard aviary conditions do not. We previously demonstrated that phosphorylation of the cyclic-AMP response element-binding protein (CREB provides a readout of the instructive signals that guide plasticity in juveniles. Here we investigated phosphorylation of calcium/calmodulin-dependent protein kinase II (pCaMKII in both juveniles and adults. In contrast to CREB, we found no differences in pCaMKII expression between prism-wearing and control juveniles within the external nucleus of the inferior colliculus (ICX, the major site of plasticity. For prism-wearing adults that hunted live mice and are capable of adaptation, expression of pCaMKII was increased relative to prism-wearing adults that fed passively on dead mice and are not capable of adaptation. This effect did not bear the hallmarks of instructive information: it was not localized to rostral ICX and did not exhibit a patchy distribution reflecting discrete bimodal stimuli. These data are consistent with a role for CaMKII as a permissive rather than an instructive factor. In addition, the paucity of pCaMKII expression in passively fed adults suggests that the permissive default setting is “off” in adults.

  17. Carotenoids, sexual signals and immune function in barn swallows from Chernobyl.

    Science.gov (United States)

    Camplani, A; Saino, N; Møller, A P

    1999-01-01

    Carotenoids have been hypothesized to facilitate immune function and act as free-radical scavengers, thereby minimizing the frequency of mutations. Populations of animals exposed to higher levels of free radicals are thus expected to demonstrate reduced sexual coloration if use of carotenoids for free-radical scavenging is traded against use for sexual signals. The intensity of carotenoid-based sexual coloration was compared among three populations of barn swallows Hirundo rustica differing in exposure to radioactive contamination. Lymphocyte and immunoglobulin concentrations were depressed, whereas the heterophil:lymphocyte ratio, an index of stress, was enhanced in Chernobyl swallows compared to controls. Spleen size was reduced in Chernobyl compared to that of two control populations. Sexual coloration varied significantly among populations, with the size of a secondary sexual character (the length of the outermost tail feathers) being positively related to coloration in the two control populations, but not in the Chernobyl population. Thus the positive covariation between coloration and sexual signalling disappeared in the population subject to intense radioactive contamination. These findings suggest that the reliable signalling function of secondary sexual characters breaks down under extreme environmental conditions, no longer providing reliable information about the health status of males. PMID:10406129

  18. Two-fold Mellin-Barnes transforms of Usyukina-Davydychev functions

    CERN Document Server

    Kniehl, Bernd; Notte-Cuello, Eduardo A; Ferrada, Ivan Parra; Rojas-Medar, Marko

    2013-01-01

    In our previous paper (Nucl.Phys.B 870 (2013) 243) we showed that multi-fold Mellin-Barnes (MB) transforms of the Usyukina-Davydychev (UD) functions may be reduced to two-fold MB transforms. The MB transforms were written there as polynomials of logarithms of ratios of squares of the external momenta with certain coefficients. We also showed that these coefficients have a combinatoric origin. In this paper we present an explicit formula for these coefficients. The procedure of recovering the coefficients is based on taking the double uni-form limit in certain series of smooth functions of two variables which is constructed according to a pre-determined iterative way. The result is obtained by using basic methods of mathematical analysis. We observe that the finiteness of the limit of this iterative chain of smooth functions should reflect itself in other mathematical constructions, too, since it is not related in any way to the explicit form of the MB transforms.

  19. Solution to Bethe-Salpeter equation via Mellin-Barnes transform

    CERN Document Server

    Allendes, Pedro; Kondrashuk, Igor; Cuello, Eduardo A Notte; Medar, Marko Rojas

    2012-01-01

    We consider Mellin-Barnes transform of triangle ladder-like scalar diagram in d=4 dimensions. It is shown how multi-fold MB transform of the momentum integral corresponding to any number of rungs is reduced to two-fold MB transform. For this purpose we use Belokurov-Usyukina reduction method for four-dimensional scalar integrals in the position space. The result is represented in terms of Euler psi-function and its derivatives. We derive new formulas for MB two-fold integration in the complex planes of two complex variables. We demonstrate that these formulas solve Bethe-Salpeter equation. We comment on further applications of solution to Bethe-Salpeter equation for vertices in N=4 supersymmetric Yang-Mills theory. We show that the recursive property of MB transforms observed in the present work for that kind of diagrams has nothing to do with quantum field theory, theory of integral transforms, or with theory of polylogarithms in general, but has an origin in a simple recursive property for smooth functions ...

  20. Two-fold Mellin-Barnes transforms of Usyukina-Davydychev functions

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Kondrashuk, Igor [Univ. del Bio Bio, Chillan (Chile). Dept. de Ciencias Basicas; Bielefeld Univ. (Germany). Fakultaet fuer Physik; Notte-Cuello, Eduardo A. [Univ. de La Serena (Chile). Dept. de Matematicas; Parra-Ferrada, Ivan [Univ. del Bio Bio, Chillan (Chile). Facultad de Educacion y Humanidades; Rojas-Medar, Marko [Univ. del Bio Bio, Chillan (Chile). Dept. de Ciencias Basicas

    2013-04-15

    In our previous paper (Nucl.Phys.B 870 (2013) 243) we showed that multi-fold Mellin-Barnes (MB) transforms of the Usyukina-Davydychev (UD) functions may be reduced to two-fold MB transforms. The MB transforms were written there as polynomials of logarithms of ratios of squares of the external momenta with certain coefficients. We also showed that these coefficients have a combinatoric origin. In this paper we present an explicit formula for these coefficients. The procedure of recovering the coefficients is based on taking the double uni-form limit in certain series of smooth functions of two variables which is constructed according to a pre-determined iterative way. The result is obtained by using basic methods of mathematical analysis. We observe that the finiteness of the limit of this iterative chain of smooth functions should reflect itself in other mathematical constructions, too, since it is not related in any way to the explicit form of the MB transforms.

  1. Two-fold Mellin–Barnes transforms of Usyukina–Davydychev functions

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd A., E-mail: kniehl@desy.de [II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Kondrashuk, Igor [Grupo de Matemática Aplicada, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Campus Fernando May, Casilla 447, Chillán (Chile); Fakultät für Physik, Universität Bielefeld, Universitätsstraße 25, 33615 Bielefeld (Germany); Notte-Cuello, Eduardo A. [Departamento de Matemáticas, Facultad de Ciencias, Universidad de La Serena, Av. Cisternas 1200, La Serena (Chile); Parra-Ferrada, Ivan [Carrera de Pedagogia en Matemática, Facultad de Educación y Humanidades, Universidad del Bío-Bío, Campus Castilla, Casilla 447, Chillán (Chile); Rojas-Medar, Marko [Grupo de Matemática Aplicada, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Campus Fernando May, Casilla 447, Chillán (Chile)

    2013-11-01

    In our previous paper (Allendes et al., 2013 [10]), we showed that multi-fold Mellin–Barnes (MB) transforms of Usyukina–Davydychev (UD) functions may be reduced to two-fold MB transforms. The MB transforms were written there as polynomials of logarithms of ratios of squares of the external momenta with certain coefficients. We also showed that these coefficients have a combinatoric origin. In this paper, we present an explicit formula for these coefficients. The procedure of recovering the coefficients is based on taking the double-uniform limit in certain series of smooth functions of two variables which is constructed according to a pre-determined iterative way. The result is obtained by using basic methods of mathematical analysis. We observe that the finiteness of the limit of this iterative chain of smooth functions should reflect itself in other mathematical constructions, too, since it is not related in any way to the explicit form of the MB transforms. This finite double-uniform limit is represented in terms of a differential operator with respect to an auxiliary parameter which acts on the integrand of a certain two-fold MB integral. To demonstrate that our result is compatible with original representations of UD functions, we reproduce the integrands of these original integral representations by applying this differential operator to the integrand of the simple integral representation of the scalar triangle four-dimensional integral J(1,1,1−ε)

  2. Solution to Bethe–Salpeter equation via Mellin–Barnes transform

    Energy Technology Data Exchange (ETDEWEB)

    Allendes, Pedro [Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción (Chile); Kniehl, Bernd A. [II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Kondrashuk, Igor, E-mail: igor.kondrashuk@gmail.com [Departamento de Ciencias Básicas, Universidad del Bío-Bío, Campus Fernando May, Casilla 447, Chillán (Chile); Notte-Cuello, Eduardo A. [Departamento de Matemáticas, Facultad de Ciencias, Universidad de La Serena, Av. Cisternas 1200, La Serena (Chile); Rojas-Medar, Marko [Departamento de Ciencias Básicas, Universidad del Bío-Bío, Campus Fernando May, Casilla 447, Chillán (Chile)

    2013-05-01

    We consider the Mellin–Barnes (MB) transform of the triangle ladder-like scalar diagram in d=4 dimensions. It is shown how the multi-fold MB transform of the momentum integral corresponding to an arbitrary number of rungs is reduced to the two-fold MB transform. For this purpose, we use the Belokurov–Usyukina reduction method for four-dimensional scalar integrals in position space. The result is represented in terms of the Euler ψ function and its derivatives. We derive new formulas for the MB two-fold integration in the complex planes of two complex variables. We demonstrate that these formulas solve the Bethe–Salpeter equation. We comment on further applications of the solution to the Bethe–Salpeter equation for the vertices in N=4 supersymmetric Yang–Mills theory. We show that the recursive property of the MB transforms observed in the present work for that kind of diagrams has nothing to do with quantum field theory, the theory of integral transforms, or the theory of polylogarithms in general, but has its origin in a simple recursive property of smooth functions, which may be shown by using basic methods of mathematical analysis.

  3. Prolonged maturation of cochlear function in the barn owl after hatching.

    Science.gov (United States)

    Köppl, Christine; Nickel, Regina

    2007-06-01

    Cochlear microphonics (CMs), which represent the electrical activity of hair cells, and compound action potentials (CAPs), which represent the activity of the auditory nerve, were recorded from the round window of the inner ear, in owlets aged between 5 and 97 days posthatching, i.e., from soon after hatching to beyond fledgling. At the earliest ages examined, animals showed very insensitive CM and virtually no CAP responses. Thus, hearing in barn owls develops entirely posthatching and the birds appear to be profoundly deaf well into the second week. Thresholds improved gradually after that and CMs reached their adult sensitivity at 5 weeks posthatching at all frequencies. Compound action potential responses appeared progressively later with increasing frequency. Adult neural sensitivity was achieved about 1 week later than for the CM responses at most frequencies, but took until 9-10 weeks posthatching at the highest frequencies (8-10 kHz). This indicates an apex-to-base maturation sequence of neural sensitivity within the cochlea, with a disproportionately long period to maturity for the most basal regions. Compound action potential amplitudes matured even later, at about 3 months posthatching, at all frequencies. This suggests a prolonged immaturity in the temporal synchrony of spiking in the auditory nerve.

  4. Influence of the facial ruff on the sound-receiving characteristics of the barn owl's ears.

    Science.gov (United States)

    von Campenhausen, Mark; Wagner, Hermann

    2006-10-01

    The barn owl, a nocturnal predator, derives its German name ("Schleiereule", direct English translation "veil owl") from the conspicuous ruff that covers the ear openings and gives the head a face-like appearance. The ruff is a specialization for the perception of sound. The densely-ramified reflector feathers forming the border of the ruff direct sound to the ear-openings. We studied the influence of the ruff on the behaviorally relevant sound-localization parameters interaural time difference (ITD) and interaural level difference (ILD). The directionality of the ear was much greater when the ruff was intact than when the reflector feathers were removed. With ruff intact, the distribution of ILDs was oblique and the maximum ITD occurred around 110 degrees of azimuth. When all head feathers were removed, the steepest ILD gradient was much closer to the horizontal axis and ITD was maximal at 90 degrees . Many effects were frequency specific. Thus, the ruff reflects some properties of the human pinna. However, by shifting the point where ITD becomes maximal beyond 90 degrees , the ruff also introduces a break of the front-back symmetry of ITD.

  5. Tuning Neuronal Hardware with Microsecond Precision: Sound Localization in the Barn Owl

    Science.gov (United States)

    van Hemmen, J. Leo

    1998-03-01

    In auditory and electrosensory neuronal systems, there seems to exist an unresolved paradox: They encode behaviorally relevant signals in the range of a few microseconds with neurons that are at least one order of magnitude slower. The barn owl's auditory system is a prominent example that may serve to provide a solution(W. Gerstner, R. Kempter, J.L. van Hemmen, and H. Wagner, Nature 383) (1996) 76--78 to the above paradox. First, neuronal output is much more accurate than the input, phprovided the presynaptic spikes arrive coherently on the average -- as they do in the adult animal. Second, this coherence in signal arrival times can be attained through unsupervised Hebbian learning (`tuning') during ontogenetic development. The learning rule governing the strength of a synapse is based on the precise timing of input as compared to output spikes. Third, the learning rule also selects the correct delays from two independent groups of input, for example, from the left and right ear and, thus, can explain the tuning to interaural time differences in the microsecond range that underlies sound localization. The relation to stochastic resonance is indicated.

  6. Misting and fan cooling of the rest area in a dairy barn

    Science.gov (United States)

    Calegari, Ferdinando; Calamari, Luigi; Frazzi, Ermes

    2012-03-01

    This summer study aimed to evaluate the effect on dairy cows, kept in a free stall barn equipped with fans and sprinklers in the feeding area, of the delivery rate of misters in a cooling system in rest areas with different bedding materials. Thirty cows were divided into two homogenous groups according to milk yield and kept in two pens: one had beds with sand (SAMM) while the other had straw (STLM). Each pen was equipped with 2 fans (Ø 70 cm, 0.50 kW) and 2 misters (delivery rate of 11.2 and 22.5 L/h in STLM and SAMM, respectively) in the rest area. Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and some milk traits were recorded. Behavioural routines of the cows (standing and lying) were also continuously recorded during the hotter days. During the trial, two mild-moderate heat waves were observed. During these hotter periods, the daily maximum temperature recorded in the rest areas was 28.9 in SAMM and 31.2 in STLM, and the daily maximum THI was 78.2 in SAMM and 81.5 in STLM. In these periods, the cows in SAMM compared with those in STLM showed lower BR ( P fans plus misters with mild wetting in rest areas with sand as bedding materials reduces heat stress and improves cow comfort.

  7. Solution to Bethe-Salpeter equation via Mellin-Barnes transform

    Energy Technology Data Exchange (ETDEWEB)

    Allendes, Pedro [Concepcion Univ. (Chile). Dept. de Fisica; Kniehl, Bernd [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Kondrashuk, Igor; Rojas Medar, Marko [Univ. del Bio-Bio, Chillan (Chile). Dept. de Ciencias Basicas; Notte Cuello, Eduardo A. [Univ. de La Serena (Chile). Facultad de Ciencias

    2012-06-15

    We consider Mellin-Barnes transform of triangle ladder-like scalar diagram in d=4 dimensions. It is shown how multi-fold MB transform of the momentum integral corresponding to any number of rungs is reduced to two-fold MB transform. For this purpose we use Belokurov-Usyukina reduction method for four-dimensional scalar integrals in the position space. The result is represented in terms of Euler {psi}-function and its derivatives. We derive new formulas for MB two-fold integration in the complex planes of two complex variables. We demonstrate that these formulas solve Bethe-Salpeter equation. We comment on further applications of solution to Bethe-Salpeter equation for vertices in N=4 supersymmetric Yang-Mills theory. We show that the recursive property of MB transforms observed in the present work for that kind of diagrams has nothing to do with quantum field theory, theory of integral transforms, or with theory of polylogarithms in general, but has an origin in a simple recursive property for smooth functions which can be shown by using basic methods of mathematical analysis.

  8. The differential hippocampal phosphoproteome of Apodemus sylvaticus paralleling spatial memory retrieval in the Barnes maze.

    Science.gov (United States)

    Li, Lin; Csaszar, Edina; Szodorai, Edit; Patil, Sudarshan; Pollak, Arnold; Lubec, Gert

    2014-05-01

    Protein phosphorylation is a well-known and well-documented mechanism in memory processes. Although a large series of protein kinases involved in memory processes have been reported, information on phosphoproteins is limited. It was therefore the aim of the study to determine a partial and differential phosphoproteome along with the corresponding network in hippocampus of a wild caught mouse strain with excellent performance in several paradigms of spatial memory. Apodemus sylvaticus mice were trained in the Barnes maze, a non-invasive test system for spatial memory and untrained mice served as controls. Animals were sacrificed 6h following memory retrieval, hippocampi were taken, proteins extracted and in-solution digestion was carried out with subsequent iTRAQ double labelling. Phosphopeptides were enriched by a TiO2-based method and semi-quantified using two fragmentation principles on the LTQ-orbitrap Velos. In hippocampi of trained animals phosphopeptide levels representing signalling, neuronal, synaptosomal, cytoskeletal and metabolism proteins were at least twofold reduced or increased. Furthermore, a network revealing a link to pathways of ubiquitination, the androgen receptor, small GTPase Rab5 and MAPK signaling as well as synucleins was constructed. This work is relevant for interpretation of previous work and the design of future studies on protein phosphorylation in spatial memory.

  9. A GPU accelerated Barnes-Hut tree code for FLASH4

    Science.gov (United States)

    Lukat, Gunther; Banerjee, Robi

    2016-05-01

    We present a GPU accelerated CUDA-C implementation of the Barnes Hut (BH) tree code for calculating the gravitational potential on octree adaptive meshes. The tree code algorithm is implemented within the FLASH4 adaptive mesh refinement (AMR) code framework and therefore fully MPI parallel. We describe the algorithm and present test results that demonstrate its accuracy and performance in comparison to the algorithms available in the current FLASH4 version. We use a MacLaurin spheroid to test the accuracy of our new implementation and use spherical, collapsing cloud cores with effective AMR to carry out performance tests also in comparison with previous gravity solvers. Depending on the setup and the GPU/CPU ratio, we find a speedup for the gravity unit of at least a factor of 3 and up to 60 in comparison to the gravity solvers implemented in the FLASH4 code. We find an overall speedup factor for full simulations of at least factor 1.6 up to a factor of 10.

  10. A GPU accelerated Barnes-Hut Tree Code for FLASH4

    CERN Document Server

    Lukat, Gunther

    2016-01-01

    We present a GPU accelerated CUDA-C implementation of the Barnes Hut (BH) tree code for calculating the gravita- tional potential on octree adaptive meshes. The tree code algorithm is implemented within the FLASH4 adaptive mesh refinement (AMR) code framework and therefore fully MPI parallel. We describe the algorithm and present test results that demonstrate its accuracy and performance in comparison to the algorithms available in the current FLASH4 version. We use a MacLaurin spheroid to test the accuracy of our new implementation and use spherical, collapsing cloud cores with effective AMR to carry out performance tests also in comparison with previous gravity solvers. Depending on the setup and the GPU/CPU ratio, we find a speedup for the gravity unit of at least a factor of 3 and up to 60 in comparison to the gravity solvers implemented in the FLASH4 code. We find an overall speedup factor for full simulations of at least factor 1.6 up to a factor of 10

  11. Quantitative genetics of migration syndromes: a study of two barn swallow populations.

    Science.gov (United States)

    Teplitsky, C; Mouawad, N G; Balbontin, J; De Lope, F; Møller, A P

    2011-09-01

    Migration is a complex trait although little is known about genetic correlations between traits involved in such migration syndromes. To assess the migratory responses to climate change, we need information on genetic constraints on evolutionary potential of arrival dates in migratory birds. Using two long-term data sets on barn swallows Hirundo rustica (from Spain and Denmark), we show for the first time in wild populations that spring arrival dates are phenotypically and genetically correlated with morphological and life history traits. In the Danish population, length of outermost tail feathers and wing length were negatively genetically correlated with arrival date. In the Spanish population, we found a negative genetic correlation between arrival date and time elapsed between arrival date and laying date, constraining response to selection that favours both early arrival and shorter delays. This results in a decreased rate of adaptation, not because of constraints on arrival date, but constraints on delay before breeding, that is, a trait that can be equally important in the context of climate change.

  12. A link between eumelanism and calcium physiology in the barn owl

    Science.gov (United States)

    Roulin, Alexandre; Dauwe, Tom; Blust, Ronny; Eens, Marcel; Beaud, Michel

    2006-09-01

    In many animals, melanin-based coloration is strongly heritable and is largely insensitive to the environment and body condition. According to the handicap principle, such a trait may not reveal individual quality because the production of different melanin-based colorations often entails similar costs. However, a recent study showed that the production of eumelanin pigments requires relatively large amounts of calcium, potentially implying that melanin-based coloration is associated with physiological processes requiring calcium. If this is the case, eumelanism may be traded-off against other metabolic processes that require the same elements. We used a correlative approach to examine, for the first time, this proposition in the barn owl, a species in which individuals vary in the amount, size, and blackness of eumelanic spots. For this purpose, we measured calcium concentration in the left humerus of 85 dead owls. Results showed that the humeri of heavily spotted individuals had a higher concentration of calcium. This suggests either that plumage spottiness signals the ability to absorb calcium from the diet for both eumelanin production and storage in bones, or that lightly spotted individuals use more calcium for metabolic processes at the expense of calcium storage in bones. Our study supports the idea that eumelanin-based coloration is associated with a number of physiological processes requiring calcium.

  13. Failing the duck test: Reply to Barbaro, Boutwell, Barnes, and Shackelford (2017).

    Science.gov (United States)

    Verhage, Marije L; Schuengel, Carlo; Fearon, R M Pasco; Madigan, Sheri; Oosterman, Mirjam; Cassibba, Rosalinda; Bakermans-Kranenburg, Marian J; van IJzendoorn, Marinus H

    2017-01-01

    In this reply, we respond to the critique by Barbaro, Boutwell, Barnes, and Shackelford (2017) in regard to our recent meta-analysis of intergenerational transmission of attachment (Verhage et al., 2016). Barbaro et al. (2017) claim that the influence of shared environment on attachment decreases with age, whereas unique environmental and genetic influences increase, which they felt was disregarded in our meta-analysis. Their criticisms, we argue, are based on a misunderstanding of the core tenets of attachment theory. Barbaro et al. (2017) unify parent-offspring attachment, attachment representations, and romantic-pair attachment under the same conceptual and empirical umbrella, even though these constructs serve different behavioral systems. We show that excluding the incompatible twin data on pair bonding from their analysis undercuts their argument. Statements about the role of the shared environment in attachment beyond early childhood are highly uncertain at this point. Importantly, even if the role of the shared environment were to wane with age, its effects may still be causally important in later childhood or adult outcomes, as either an indirect factor or as a factor influencing earlier developmental outcomes. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2001-04-01

    The activities of the Reactor Materials Research Department of the Belgian Nuclear Research Centre SCK-CEN in 2000 are summarised. The programmes within the department are focussed on studies concerning (1) fusion, in particular mechanical testing; (2) Irradiation Assisted Stress Corrosion Cracking (IASCC); (3) nuclear fuel; and (4) Reactor Pressure Vessel Steel (RPVS)

  15. Space Nuclear Reactor Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-06

    We needed to find a space reactor concept that could be attractive to NASA for flight and proven with a rapid turnaround, low-cost nuclear test. Heat-pipe-cooled reactors coupled to Stirling engines long identified as the easiest path to near-term, low-cost concept.

  16. Light water reactor program

    Energy Technology Data Exchange (ETDEWEB)

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  17. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  18. Nuclear reactor design

    CERN Document Server

    2014-01-01

    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  19. Mirror reactor surface study

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. L.; Damm, C. C.; Futch, A. H.; Hiskes, J. R.; Meisenheimer, R. G.; Moir, R. W.; Simonen, T. C.; Stallard, B. W.; Taylor, C. E.

    1976-09-01

    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included.

  20. In vitro production of tumor necrosis factor-alpha by human monocytes stimulated with lipopolysaccharide is positively correlated with increased blood monocytes after exposure to a swine barn.

    Science.gov (United States)

    Willson, P J; Khozani, T Talaei; Juurlink, B H J; Senthilselvan, A; Rennie, D C; Gerdts, V; Gawaziuk, J; Schneberger, D; Burch, Lauranell H; Dosman, J A

    2008-01-01

    Recently there has been interest in the air quality in and around intensive livestock production facilities, such as modern swine production barns, where agricultural workers and surrounding residents may be exposed to elevated levels of organic dusts. The health effects of these exposures are not completely understood. The study that is reported here is a component of a larger investigation of the relationships among the acute effects of high-concentration endotoxin exposure (swine barn dust), polymorphisms in the TLR4 gene, and respiratory outcomes following exposure to swine confinement buildings. The relationships among a mediator of acute lung inflammation, tumor necrosis factor alpha (TNF-alpha), and clinical responses to acute swine barn exposure were characterized. Analysis of the results showed that in vitro stimulation of human monocytes with as little as 1 ng/ml of lipopolysaccharide (LPS) produced a significant increase in the monocytes that produced TNF-alpha. Although the proportion of TNF-alpha-positive monocytes after in vitro stimulation with 1 ng/ml of LPS was not associated with gender or TLR4 genotype, it was positively associated with the concentration of monocytes in blood after barn exposure. Thus, these two responses to different forms of LPS exposure are significantly correlated, and more responsive monocytes in vitro indicate a forthcoming relative monocytosis, post barn exposure, which may initiate a cascade of chronic inflammation.

  1. Biobanken i Den norske mor og barn undersøkelsen

    Directory of Open Access Journals (Sweden)

    Kjersti S. Rønningen

    2009-10-01

    Full Text Available  Biobanker for langtidslagring av biologisk materiale blir en viktigere og viktigere del av epidemiologiske studier. I planleggingen av en biobank er det en rekke avgjørelser som må tas for å sikre best mulig oppslutning både med hensyn til å få inn så mange prøver som mulig og å oppnå best mulig prøvekvalitet både på kort og lang sikt. Den norske mor og barn undersøkelsen (MoBa skal inkludere 100 000 svangerskap og følge mor, far og barn i lang tid fremover. Innsamlingen av data startet i ett fylke i 1999, og omfatter i dag hele landet. Siden det tas blodprøver to ganger fra hver kvinne, blodprøve fra far og navlesnorsblod frabarna, betydde dette at Biobanken for MoBa måtte planlegges for å kunne motta og langtidslagre over 380 000 prøvesett. Ved Biobanken ved Nasjonalt folkehelseinstitutt lagres fullblod, plasma, urin, DNA og spesialrør til senere RNA isolering. Rekruttering til MoBa foregår ved 52 av landets sykehus. Prøvene sendes per post til Biobanken ved Folkehelseinstituttet for prosessering. Per januar 2006 er over 200 000 prøvesett lagret ved Biobanken. Denne artikkelen gir en kortfattet oversikt over oppbyggingen av Biobanken og logistikken knyttet til innsamlingen av biologisk materiale, fra blodet tappes til det er sikkert lagret og klart til å tas ut på et senere tidspunkt, kanskje mange år inn i fremtiden.The biobank in The Norwegian Mother and Child Cohort Study.Long term storage of biological material is becoming a critical component of many epidemiological studies. In designing specimen repositories, efforts need to be made to balance future needs for samples with logistical constraints necessary to process and store samples in a timely fashion. The Norwegian Mother and Child Cohort Study was started in 1999 and aims at including 100,000 pregnancies, and will follow mother, father and child for many years to come. The Biobank was faced with the challenge to receive and store over 380,000 biological

  2. Effects of biofilter media depth and moisture content on removal of gases from a swine barn.

    Science.gov (United States)

    Liu, Tongshuai; Dong, Hongmin; Zhu, Zhiping; Shang, Bin; Yin, Fubin; Zhang, Wanqin; Zhou, Tanlong

    2017-04-28

    Media depth (MD) and moisture content (MC) are two important factors that greatly influence biofilters performance. The purpose of this study was to investigate the combined effect of MC and MD on removing ammonia (NH3), hydrogen sulfide (H2S), and nitrous oxide (N2O) from swine barns. Biofiltration performance of different MDs and MCs combination based on the mixed medium of wood chips and compost were monitored. A 3×3 factorial design was adopted, which included three levels of the two factors (MC: 45%, 55%, and 67% (wet basis); MD: 0.17, 0.33, and 0.50 m). Results indicated that high MC and MD could improve NH3 removal efficiency, but increase outlet N2O concentration. When MC was 67%, the average NH3 removal efficiency of three MDs (0.17, 0.33, and, 0.50 m) ranged from 77.4% to 78.7%; and the range of average H2S removal efficiency dropped from 68.1%-90.0% (1-34 days of the test period) to 36.8%-63.7% (35-58 days of the test period); and the average outlet N2O concentration increased by 25.5%-60.1%. When MC was 55%, the average removal efficiency of NH3, H2S, and N2O for treatment with 0.33 m MD was 72.8%±5.9%, 70.9%±13.3%, and ?18.9%±8.1%, respectively; and the average removal efficiency of NH3, H2S, and N2O for treatment with 0.50 m MD was 77.7%±4.2%, 65.8%±13.7%, and ?24.5%±12.1%, respectively. When MC was 45%, the highest average NH3 reduction efficiency among three MDs was 60.7% for 0.5 m MD, and the average N2O removal efficiency for three MDs ranged from ?18.8% to ?12.7%. In addition, the pressure drop of 0.33 m MD was significantly lower than that of 0.50 m MD (P biofilters with three different media depths (0.17, 0.33, and 0.50 m) and three different media moisture contents (45%, 55%, and 67% (wet basis)) were compared to remove gases from a swine barn. Using wood chips and compost mixture as the biofilters media, combination of 0.33 m media depth and 55% media moisture content is recommended to obtain good reduction of NH3 and H2S, and

  3. Cooling systems of the resting area in free stall dairy barn.

    Science.gov (United States)

    Calegari, F; Calamari, L; Frazzi, E

    2016-04-01

    A study during the summer season evaluated the effect of different cooling systems on behavioral and productive responses of Italian Friesian dairy cows kept in an experimental-free stall barn located in the Po Valley in Italy. The study involved 30 lactating dairy cows subdivided into two groups kept in two pens with external hard court paddock in each free stall. The same cooling system was applied in the feeding area in both pens. A different cooling system in the resting area was applied to the two pens: in the pen SW, the resting area was equipped with fans and misters; in the other, there was simple ventilation (SV). Breathing rate, rectal temperature, milk yield, and milk characteristics (fat, protein, and somatic cell count) were measured. Behavioral activities (standing and lying cows in the different areas, as well as the animals in the feed bunk) were recorded. Mild to moderate heat waves during the trial were observed. On average, the breathing rate was numerically greater in SV compared with SW cows (60.2 and 55.8 breath/min, respectively), and mean rectal temperature remained below 39 °C in both groups during the trial (on average 38.7 and 38.8 °C in SV and SW, respectively. During the hotter periods of the trial, the time spent lying indoor in the free stall was greater in SW (11.8 h/day) than SV (10.7 h/day). Conversely, the time spent standing indoor without feeding was greater in SV (4.3 h/day) than SW (3.8 h/day). Milk yield was slightly better maintained during hotter period in SW compared with SV and somatic cell count was also slightly greater in the former. In conclusion, the adoption of the cooling system by means of evaporative cooling also in the resting area reduces the alteration of time budget caused by heat stress.

  4. Klatring i trær og hyttebygging: - om barns lek og lekesteder ute

    Directory of Open Access Journals (Sweden)

    Merete Lund Fasting

    2015-07-01

    Full Text Available Abstract: This article describes 10 year old children`s play in nature during school hours. However, my result does equally reflect on children in kindergarden as well. Observation and conversation was used as methods as well as pictures. The children’s play in the trees and building huts was conducted in groups, and their communication was nonverbal with each other and with the nature. However; the girls reveal that they enjoy their conversations while being in the tree. The children often play at the same place over and over. This is significant to the evolution of the play and the children’s communication with their places in nature.Sammendrag: Denne artikkelen omhandler 10 år gamle barns lek på natursteder i skoletida. Selv om studien omhandler 10 åringer så kan kunnskapen den frembringer også være viktig for å forstå barnehagebarns lek og tilknytning til sine lekesteder i barnehagen. Metodene som ble brukt for å undersøke barnas lek var observasjoner og samtaler med barna, i tillegg til fotografier. Barnas lek i trærne og i hyttebyggingen karakteriseres ved at de er flere sammen, og barna har en kroppslig dialog med hverandre og omgivelsene i leken. Barna snakker i liten grad sammen om leken og hvordan de skal leke; deres kommunikasjon er hovedsakelig nonverbal. Men når jentene sitter i treet forteller de meg at de liker å sitte og snakke. Barna leker på steder hvor de har vært mye før, og dette har en betydning for barnas lek og barnas kommunikasjon med deres steder.

  5. Eggshell bacterial load is related to antimicrobial properties of feathers lining barn swallow nests.

    Science.gov (United States)

    Peralta-Sánchez, Juan Manuel; Soler, Juan José; Martín-Platero, Antonio Manuel; Knight, Rob; Martínez-Bueno, Manuel; Møller, Anders Pape

    2014-02-01

    The use of feathers to line bird's nests has traditionally been interpreted as having a thermoregulatory function. Feather-degrading bacteria growing on feathers lining nests may have antimicrobial properties, which may provide an additional benefit to lining nests with feathers. We test the hypothesis that the production of antimicrobial substances by feather bacteria affects the microbiological environment of the nest, and therefore the bacterial density on eggshells and, indirectly, hatching success. These effects would be expected to differ between nests lined with pigmented and white feathers, because bacteria grow differently on feathers of different colors. We experimentally manipulated the composition of pigmented and unpigmented feathers in nests of the barn swallow (Hirundo rustica) and studied the antimicrobial properties against the keratin-degrading bacterium Bacillus licheniformis of bacteria isolated from feathers of each color. Analyzed feathers were collected at the end of the incubation period, and antimicrobial activity was defined as the proportion of bacteria from the feathers that produce antibacterial substances effective against B. licheniformis. Our experimental manipulation affected antimicrobial activity, which was higher in nests with only white feathers at the beginning of incubation. Moreover, white feathers showed higher antimicrobial activity than black ones. Interestingly, antimicrobial activity in feathers of one of the colors correlated negatively with bacterial density on feather of the opposite color. Finally, antimicrobial activity of white feathers was negatively related to eggshell bacterial load. These results suggest that antimicrobial properties of feathers in general and of white feathers in particular affect the bacterial environment in nests. This environment in turn affects the bacterial load on eggshells, which may affect hatching success.

  6. A trade-off between reproduction and feather growth in the barn swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    Full Text Available Physiological trade-offs mediated by limiting energy, resources or time constrain the simultaneous expression of major functions and can lead to the evolution of temporal separation between demanding activities. In birds, plumage renewal is a demanding activity, which accomplishes fundamental functions, such as allowing thermal insulation, aerodynamics and socio-sexual signaling. Feather renewal is a very expensive and disabling process, and molt is often partitioned from breeding and migration. However, trade-offs between feather renewal and breeding have been only sparsely studied. In barn swallows (Hirundo rustica breeding in Italy and undergoing molt during wintering in sub-Saharan Africa, we studied this trade-off by removing a tail feather from a large sample of individuals and analyzing growth bar width, reflecting feather growth rate, and length of the growing replacement feather in relation to the stage in the breeding cycle at removal and clutch size. Growth bar width of females and length of the growing replacement feather of both sexes were smaller when the original feather had been removed after clutch initiation. Importantly, in females both growth bar width and replacement feather length were negatively predicted by clutch size, and more strongly so for large clutches and when feather removal occurred immediately after clutch completion. Hence, we found strong, coherent evidence for a trade-off between reproduction, and laying effort in particular, and the ability to generate new feathers. These results support the hypothesis that the derived condition of molting during wintering in long-distance migrants is maintained by the costs of overlapping breeding and molt.

  7. Timing of molt of barn swallows is delayed in a rare Clock genotype

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    2013-02-01

    Full Text Available Photoperiodic responses are major factors entraining circannual life-cycles, functioning to adaptively synchronize annual routines to seasonal fluctuations in ecological conditions. Photoperiodism in physiology and behaviour is enforced by genes, including the vertebrate Clock orthologues, which are associated, for example, with phenology of migration in fish and breeding in birds. However, the role of Clock in photoperiodic plumage molt processes is unknown. We analyzed variation in molt schedules in relation to Clock genotype, using the long-distance migratory barn swallow (Hirundo rustica as a model and by identifying males and females using molecular sexing techniques. Consistently with previous studies, we found one very common (Q7 and two rare (Q6, Q8 variants of a functionally significant Clock polyglutamine repeat. Molt schedules of primary wing feathers of swallows during their wintering period in Nigeria differed among Clock genotypes: rare (1.1% Q7/Q8 heterozygotes had significantly delayed molt compared to the other genotypes. Molt schedules did not differ between males and females, and no differential association between molt and Clock in relation to sex emerged. The same rare Clock genotype that exhibited delayed breeding in Europe was here found to delay molt in Africa. Though based on a limited number of Q7/Q8 individuals from an otherwise very large sample, these novel results suggest that Clock is involved in the photoperiodic control of both molt and breeding, potentially also via reciprocal carry-over effects. If confirmed in species with higher Clock polymorphism, present results may have far-reaching consequences for the study of photoperiodic control of molt and expression of annual routines.

  8. The sensitive period for auditory localization in barn owls is limited by age, not by experience.

    Science.gov (United States)

    Knudsen, E I; Knudsen, P F

    1986-07-01

    Early in life, the barn owl passes through a sensitive period during which it can interpret and make use of abnormal auditory cues for accurate sound localization. This capacity is lost at about 8 weeks of age, just after the head and ears reach adult size (knudsen et al. 1984a). The end of the sensitive period could be triggered either by an age-dependent process or by the exposure of the auditory system to stable or adult-like cues. To distinguish between these alternatives, we subjected baby owls to constant abnormal cues (chronic monaural occlusion) or to frequently changing abnormal cues (alternating monaural occlusion) throughout the sensitive period. In the first group of animals (n = 2), one ear was plugged continuously until 73 or 79 d of age, respectively, and then the earplug was switched to the opposite ear. Although these animals adjusted sound localization accuracy during the initial chronic monaural occlusion, they could not localize sounds at all after the earplug was switched to the opposite ear, and they remained unable to localize sounds as long as the opposite ear remained occluded (7 and 27 weeks, respectively). When the second monaural occlusion was finally removed, both birds localized sounds with errors that were similar to the errors they exhibited immediately after removal of the first monaural occlusion. One bird that was 127-d-old at the time the second earplug was removed corrected its localization error; the other bird, 250-d-old when the second earplug was removed, did not.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Projections of the cochlear nuclei and nucleus laminaris to the inferior colliculus of the barn owl.

    Science.gov (United States)

    Takahashi, T T; Konishi, M

    1988-08-08

    The barn owl determines the directions from which sounds emanate by computing the interaural differences in the timing and intensity of sounds. These cues for sound localization are processed in independent channels originating at nucleus magnocellularis (NM) and nucleus angularis (NA), the cochlear nuclei. The cells of NM are specialized for encoding the phase of sounds in the ipsilateral ear. The cells of NA are specialized for encoding the intensity of sounds in the ipsilateral ear. NM projects solely, bilaterally, and tonotopically to nucleus laminaris (NL). NL and NA project to largely nonoverlapping zones in the central nucleus of the inferior colliculus (ICc), thus forming hodological subdivisions in which time and intensity information may be processed. The terminal field of NL occupies a discrete zone in the rostromedial portion of the contralateral ICc, which we have termed the "core" of ICc. The terminal field of NA surrounds the core of ICc and thus forms a "shell" around it. The projection from NL to the core conserves tonotopy. Low-frequency regions of NL project to the dorsal portions of the core whereas higher-frequency regions project to more ventral portions. This innervation pattern is consistent with earlier physiological studies of tonotopy. Physiological studies have also suggested that NL and the core of ICs contain a representation of the location of a sound source along the horizontal axis. Our data suggest that the projection from NL to the core preserves spatiotopy. Thus, the dorsal portion of NL on the left, which contains a representation of eccentric loci in the right hemifield, innervates the area of the right ICc core that represents eccentric right loci. The more ventral portion of the left NL, which represents loci close to the vertical meridian, innervates the more rostral portions of the right core, which also represents loci near the vertical meridian.

  10. Response of auditory units in the barn owl's inferior colliculus to continuously varying interaural phase differences.

    Science.gov (United States)

    Moiseff, A; Haresign, T

    1992-06-01

    1. We studied the response of single units in the central nucleus of the inferior colliculus (ICc) of the barn owl (Tyto alba) to continuously varying interaural phase differences (IPDs) and static IPDs. Interaural phase was varied in two ways: continuously, by delivering tones to each ear that varied by a few hertz (binaural beat, Fig. 1), and discretely, by delaying in fixed steps the phase of sound delivered to one ear relative to the other (static phase). Static presentations were repeated at several IPDs to characterize interaural phase sensitivity. 2. Units sensitive to IPDs responded to the binaural beat stimulus over a broad range of delta f(Fig. 4). We selected a 3-Hz delta f for most of our comparative measurements on the basis of constraints imposed by our stimulus generation system and because it allowed us to reduce the influence of responses to stimulus onset and offset (Fig. 3A). 3. Characteristic interaural time or phase sensitivity obtained by the use of the binaural beat stimulus were comparable with those obtained by the use of the static technique (Fig. 5; r2 = 0.93, Fig. 6). 4. The binaural beat stimulus facilitated the measurement of characteristic delay (CD) and characteristic phase (CP) of auditory units. We demonstrated that units in the owl's inferior colliculus (IC) include those that are maximally excited by specific IPDs (CP = 0 or 1.0) as well as those that are maximally suppressed by specific IPDs (CP = 0.5; Figs. 7 and 8). 5. The selectivity of units sensitive to IPD or interaural time difference (ITD) were weakly influenced by interaural intensity difference (IID).(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Sexual dimorphism in melanin pigmentation, feather coloration and its heritability in the barn swallow (Hirundo rustica).

    Science.gov (United States)

    Saino, Nicola; Romano, Maria; Rubolini, Diego; Teplitsky, Celine; Ambrosini, Roberto; Caprioli, Manuela; Canova, Luca; Wakamatsu, Kazumasa

    2013-01-01

    Melanin is the main pigment in animal coloration and considerable variation in the concentrations of the two melanin forms (pheo- and eumlanin) in pigmented tissues exists among populations and individuals. Melanin-based coloration is receiving increasing attention particularly in socio-sexual communication contexts because the melanocortin system has been hypothesized to provide a mechanistic basis for covariation between coloration and fitness traits. However, with few notable exceptions, little detailed information is available on inter-individual and inter-population variation in melanin pigmentation and on its environmental, genetic and ontogenetic components. Here, we investigate melanin-based coloration in an Italian population of a passerine bird, the barn swallow (Hirundo rustica rustica), its sex- and age-related variation, and heritability. The concentrations of eu- and pheomelanin in the throat (brown) and belly (white-to-brownish) feathers differed between sexes but not according to age. The relative concentration of either melanin (Pheo:Eu) differed between sexes in throat but not in belly feathers, and the concentrations in males compared to females were larger in belly than in throat feathers. There were weak correlations between the concentrations of melanins within as well as among plumage regions. Coloration of belly feathers was predicted by the concentration of both melanins whereas coloration of throat feathers was only predicted by pheomelanin in females. In addition, Pheo:Eu predicted coloration of throat feathers in females and that of belly feathers in males. Finally, we found high heritability of color of throat feathers. Melanization was found to differ from that recorded in Hirundo rustica rustica from Scotland or from H. r. erythrogaster from North America. Hence, present results show that pigmentation strategies vary in a complex manner according to sex and plumage region, and also among geographical populations, potentially

  12. Cooling systems of the resting area in free stall dairy barn

    Science.gov (United States)

    Calegari, F.; Calamari, L.; Frazzi, E.

    2016-04-01

    A study during the summer season evaluated the effect of different cooling systems on behavioral and productive responses of Italian Friesian dairy cows kept in an experimental-free stall barn located in the Po Valley in Italy. The study involved 30 lactating dairy cows subdivided into two groups kept in two pens with external hard court paddock in each free stall. The same cooling system was applied in the feeding area in both pens. A different cooling system in the resting area was applied to the two pens: in the pen SW, the resting area was equipped with fans and misters; in the other, there was simple ventilation (SV). Breathing rate, rectal temperature, milk yield, and milk characteristics (fat, protein, and somatic cell count) were measured. Behavioral activities (standing and lying cows in the different areas, as well as the animals in the feed bunk) were recorded. Mild to moderate heat waves during the trial were observed. On average, the breathing rate was numerically greater in SV compared with SW cows (60.2 and 55.8 breath/min, respectively), and mean rectal temperature remained below 39 °C in both groups during the trial (on average 38.7 and 38.8 °C in SV and SW, respectively. During the hotter periods of the trial, the time spent lying indoor in the free stall was greater in SW (11.8 h/day) than SV (10.7 h/day). Conversely, the time spent standing indoor without feeding was greater in SV (4.3 h/day) than SW (3.8 h/day). Milk yield was slightly better maintained during hotter period in SW compared with SV and somatic cell count was also slightly greater in the former. In conclusion, the adoption of the cooling system by means of evaporative cooling also in the resting area reduces the alteration of time budget caused by heat stress.

  13. Barn owl feathers as biomonitors of mercury: sources of variation in sampling procedures.

    Science.gov (United States)

    Roque, Inês; Lourenço, Rui; Marques, Ana; Coelho, João Pedro; Coelho, Cláudia; Pereira, Eduarda; Rabaça, João E; Roulin, Alexandre

    2016-04-01

    Given their central role in mercury (Hg) excretion and suitability as reservoirs, bird feathers are useful Hg biomonitors. Nevertheless, the interpretation of Hg concentrations is still questioned as a result of a poor knowledge of feather physiology and mechanisms affecting Hg deposition. Given the constraints of feather availability to ecotoxicological studies, we tested the effect of intra-individual differences in Hg concentrations according to feather type (body vs. flight feathers), position in the wing and size (mass and length) in order to understand how these factors could affect Hg estimates. We measured Hg concentration of 154 feathers from 28 un-moulted barn owls (Tyto alba), collected dead on roadsides. Median Hg concentration was 0.45 (0.076-4.5) mg kg(-1) in body feathers, 0.44 (0.040-4.9) mg kg(-1) in primary and 0.60 (0.042-4.7) mg kg(-1) in secondary feathers, and we found a poor effect of feather type on intra-individual Hg levels. We also found a negative effect of wing feather mass on Hg concentration but not of feather length and of its position in the wing. We hypothesize that differences in feather growth rate may be the main driver of between-feather differences in Hg concentrations, which can have implications in the interpretation of Hg concentrations in feathers. Finally, we recommend that, whenever possible, several feathers from the same individual should be analysed. The five innermost primaries have lowest mean deviations to both between-feather and intra-individual mean Hg concentration and thus should be selected under restrictive sampling scenarios.

  14. Effect of summer grazing on welfare of dairy cows reared in mountain tie-stall barns

    Directory of Open Access Journals (Sweden)

    Simonetta Dovier

    2010-09-01

    Full Text Available Traditional mountain farms have an important economic, social and environmental role. The Alps management system for dairy cows consists of animals kept indoors from autumn to spring, mostly in tie-stalls, and moved to mountain pasture in summer. The aim of our study was to assess the effect of mountain summer grazing on the welfare of dairy cows housed in tie-stall barns. Twenty-four farms were considered. In twelve of them, animals were reared in tie-stalls and moved to mountain pasture for three months in summer; they were visited three times: (i four weeks before grazing during the indoor period in the stall; (ii about three weeks after the start of grazing; and (iii in the stall, in autumn, at least three weeks after returning from grazing. The other twelve farms kept the animals in tie-stalls all year; they were visited once in autumn. Data were collected following a protocol that considers animal-based measures and structure information on the basis of Quality Welfare Consortium® indications. Data allowed the calculation of both the Animal Needs Index score (ANI 35L and an overall assessment of the cows’ welfare obtained from three general aspects: housing, animal’s physical condition, and animal’s behaviour. Summer grazing had a significant positive effect on injuries, lameness and animal’s rising duration but a negative effect on faeces consistency. Moreover, a reduction of tongue playing was observed. The ANI 35L and the overall assessment did not show significant differences linked to summer grazing, which tended to have a positive but temporary effect on animal behaviour.

  15. Slurry reactor design studies

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. (Bechtel Group, Inc., San Francisco, CA (USA)); Akgerman, A. (Texas A and M Univ., College Station, TX (USA)); Smith, J.M. (California Univ., Davis, CA (USA))

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  16. Natural selection in a postglacial range expansion: the case of the colour cline in the European barn owl.

    Science.gov (United States)

    Antoniazza, Sylvain; Kanitz, Ricardo; Neuenschwander, Samuel; Burri, Reto; Gaigher, Arnaud; Roulin, Alexandre; Goudet, Jérôme

    2014-11-01

    Gradients of variation--or clines--have always intrigued biologists. Classically, they have been interpreted as the outcomes of antagonistic interactions between selection and gene flow. Alternatively, clines may also establish neutrally with isolation by distance (IBD) or secondary contact between previously isolated populations. The relative importance of natural selection and these two neutral processes in the establishment of clinal variation can be tested by comparing genetic differentiation at neutral genetic markers and at the studied trait. A third neutral process, surfing of a newly arisen mutation during the colonization of a new habitat, is more difficult to test. Here, we designed a spatially explicit approximate Bayesian computation (ABC) simulation framework to evaluate whether the strong cline in the genetically based reddish coloration observed in the European barn owl (Tyto alba) arose as a by-product of a range expansion or whether selection has to be invoked to explain this colour cline, for which we have previously ruled out the actions of IBD or secondary contact. Using ABC simulations and genetic data on 390 individuals from 20 locations genotyped at 22 microsatellites loci, we first determined how barn owls colonized Europe after the last glaciation. Using these results in new simulations on the evolution of the colour phenotype, and assuming various genetic architectures for the colour trait, we demonstrate that the observed colour cline cannot be due to the surfing of a neutral mutation. Taking advantage of spatially explicit ABC, which proved to be a powerful method to disentangle the respective roles of selection and drift in range expansions, we conclude that the formation of the colour cline observed in the barn owl must be due to natural selection.

  17. Sexual Dimorphism and Population Differences in Structural Properties of Barn Swallow (Hirundo rustica Wing and Tail Feathers.

    Directory of Open Access Journals (Sweden)

    Péter L Pap

    Full Text Available Sexual selection and aerodynamic forces affecting structural properties of the flight feathers of birds are poorly understood. Here, we compared the structural features of the innermost primary wing feather (P1 and the sexually dimorphic outermost (Ta6 and monomorphic second outermost (Ta5 tail feathers of barn swallows (Hirundo rustica from a Romanian population to investigate how sexual selection and resistance to aerodynamic forces affect structural differences among these feathers. Furthermore, we compared structural properties of Ta6 of barn swallows from six European populations. Finally, we determined the relationship between feather growth bars width (GBW and the structural properties of tail feathers. The structure of P1 indicates strong resistance against aerodynamic forces, while the narrow rachis, low vane density and low bending stiffness of tail feathers suggest reduced resistance against airflow. The highly elongated Ta6 is characterized by structural modifications such as large rachis width and increased barbule density in relation to the less elongated Ta5, which can be explained by increased length and/or high aerodynamic forces acting at the leading tail edge. However, these changes in Ta6 structure do not allow for full compensation of elongation, as reflected by the reduced bending stiffness of Ta6. Ta6 elongation in males resulted in feathers with reduced resistance, as shown by the low barb density and reduced bending stiffness compared to females. The inconsistency in sexual dimorphism and in change in quality traits of Ta6 among six European populations shows that multiple factors may contribute to shaping population differences. In general, the difference in quality traits between tail feathers cannot be explained by the GBW of feathers. Our results show that the material and structural properties of wing and tail feathers of barn swallows change as a result of aerodynamic forces and sexual selection, although the

  18. Measurement of heat stress conditions at cow level and comparison to climate conditions at stationary locations inside a dairy barn.

    Science.gov (United States)

    Schüller, Laura K; Heuwieser, Wolfgang

    2016-08-01

    The objectives of this study were to examine heat stress conditions at cow level and to investigate the relationship to the climate conditions at 5 different stationary locations inside a dairy barn. In addition, we compared the climate conditions at cow level between primiparous and multiparous cows for a period of 1 week after regrouping. The temperature-humidity index (THI) differed significantly between all stationary loggers. The lowest THI was measured at the window logger in the experimental stall and the highest THI was measured at the central logger in the experimental stall. The THI at the mobile cow loggers was 2·33 THI points higher than at the stationary loggers. Furthermore, the mean daily THI was higher at the mobile cow loggers than at the stationary loggers on all experimental days. The THI in the experimental pen was 0·44 THI points lower when the experimental cow group was located inside the milking parlour. The THI measured at the mobile cow loggers was 1·63 THI points higher when the experimental cow group was located inside the milking parlour. However, there was no significant difference for all climate variables between primiparous and multiparous cows. These results indicate, there is a wide range of climate conditions inside a dairy barn and especially areas with a great distance to a fresh air supply have an increased risk for the occurrence of heat stress conditions. Furthermore, the heat stress conditions are even higher at cow level and cows not only influence their climatic environment, but also generate microclimates within different locations inside the barn. Therefore climate conditions should be obtained at cow level to evaluate the heat stress conditions that dairy cows are actually exposed to.

  19. Final work plan : targeted groundwater sampling and monitoring well installation for potential site reclassification at Barnes, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.

    2006-07-11

    This ''Work Plan'' outlines the scope of work for a targeted groundwater sampling investigation and monitoring well installation at Barnes, Kansas. This activity is being conducted at the request of the Kansas Department of Health and Environment (KDHE), in accordance with the intergovernmental agreement between the KDHE and the Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA). Data resulting from the proposed work will be used to determine the hydraulic gradient near the former CCC/USDA facility, delineate the downgradient carbon tetrachloride plume, and determine additional monitoring requirements at Barnes. The overall goal is to establish criteria for monitoring leading to potential site reclassification. The proposed work will be performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy (DOE). The Farm Service Agency of the USDA has entered into an interagency agreement with DOE, under which Argonne provides technical assistance with environmental site characterization and remediation at former CCC/USDA grain storage facilities. Argonne issued a ''Master Work Plan'' (Argonne 2002) to provide general guidance for all investigations at former CCC/USDA facilities in Kansas. The ''Master Work Plan'', approved by the KDHE, contains the materials common to investigations at all locations in Kansas. This document must be consulted for the complete details of plans for this work associated with the former CCC/USDA facility at Barnes.

  20. Clock gene variation is associated with breeding phenology and maybe under directional selection in the migratory barn swallow.

    Directory of Open Access Journals (Sweden)

    Manuela Caprioli

    Full Text Available BACKGROUND: In diverse taxa, photoperiodic responses that cause seasonal physiological and behavioural shifts are controlled by genes, including the vertebrate Clock orthologues, that encode for circadian oscillator mechanisms. While the genetic network behind circadian rhythms is well described, relatively few reports exist of the phenological consequences of and selection on Clock genes in the wild. Here, we investigated variation in breeding phenology in relation to Clock genetic diversity in a long-distance migratory bird, the barn swallow (Hirundo rustica. METHODOLOGY/PRINCIPAL FINDINGS: In a sample of 922 adult barn swallows from a single population breeding in Italy we found one very common (Q(7 and three rare (Q(5, Q(6, Q(8 length variants of a functionally significant polyglutamine repeat. Rare (2.9% Q(7/Q(8 heterozygous females, but not males, bred significantly later than common (91.5% Q(7/Q(7 females, consistent with the expectation that 'long' alleles cause late breeding, as observed in a resident population of another bird species. Because breeding date depends on arrival date from migration, present results suggest that the association between breeding date and Clock might be mediated by migration phenology. In addition, fecundity selection appears to be operating against Q(7/Q(8 because late migrating/breeding swallows have fewer clutches per season, and late breeding has additional negative selection effects via reduced offspring longevity. Genotype frequencies varied marginally non-significantly with age, as Q(7/Q(8 frequency showed a 4-fold reduction in old individuals. This result suggests negative viability selection against Q(7/Q(8, possibly mediated by costs of late breeding. CONCLUSIONS/SIGNIFICANCE: This is the first study of migratory birds showing an association between breeding phenology and Clock genotype and suggesting that negative selection occurs on a phenologically deviant genotype. Low polymorphism at Clock may

  1. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  2. Gas cooled fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-06-01

    Although most of the development work on fast breeder reactors has been devoted to the use of liquid metal cooling, interest has been expressed for a number of years in alternative breeder concepts using other coolants. One of a number of concepts in which interest has been retained is the Gas-Cooled Fast Reactor (GCFR). As presently envisioned, it would operate on the uranium-plutonium mixed oxide fuel cycle, similar to that used in the Liquid Metal Fast Breeder Reactor (LMFBR), and would use helium gas as the coolant.

  3. Microfluidic electrochemical reactors

    Science.gov (United States)

    Nuzzo, Ralph G [Champaign, IL; Mitrovski, Svetlana M [Urbana, IL

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  4. EVALUATION OF PERCEIVED QUALITY OF THE WEBSITE OF AN ONLINE BOOKSTORE: AN EMPIRICAL APPLICATION OF THE BARNES AND VIDGEN MODEL

    Directory of Open Access Journals (Sweden)

    Ueliton da Costa Leonidio

    2011-05-01

    Full Text Available This paper’s objective is to evaluate the perceived quality of the Website of an online bookstore using the Barnes and Vidgen Model. Implemented over the Internet, this empirical research collected data on the perceived quality of the Website, used to sell products and online services. The questionnaire used to gather the data was answered by a convenience sample of 213 respondents. The importance of quality attributes and the dimension of perceived quality were investigated. The results indicate that the three dimensions named Reliability, Usability and Information were the most noticeable.

  5. Effect of Applying Surplus Heat Sharing in Bulk Curing Barn%密集烤房余热共享应用效果研究

    Institute of Scientific and Technical Information of China (English)

    张丽英; 谢帮金; 杨启冰; 刘勇; 李立新; 齐飞

    2014-01-01

    通过比较余热共享密集烤房与无余热共享密集烤房在烘烤过程中能耗和鲜干比值的变化,研究了余热共享密集烤房的应用效果。结果表明:余热共享密集烤房的耗煤量、耗电量和鲜干比值均优于无余热共享密集烤房,有效地降低了烘烤成本。密集烤房通过余热共享,可以降低顶层烟叶烘烤后的含青度,提高顶层烟叶烘烤质量。%The effect of applying surplus heat sharing in bulk curing barn was studied by comparing the variation of energy consumption and ratio of dry weight to fresh weight in flue-curing process between bulk curing barn with surplus heat sharing and normal bulk curing barn. The results showed that in comparison normal bulk curing barn, the coal consumption, the power consumption and the ratio of dry weight to fresh weight of bulk curing barn with surplus heat sharing were all relatively better, thus reducing the curing cost effectively. Through surplus heat sharing, the bulk curing barn can reduce the green degree of top layer tobacco leaves after curing, thus improving the curing quality of top layer tobacco leaves.

  6. The effects of apparatus design and test procedure on learning and memory performance of C57BL/6J mice on the Barnes maze.

    Science.gov (United States)

    O'Leary, Timothy P; Brown, Richard E

    2012-01-30

    The Barnes maze is a visuo-spatial learning and memory test originally designed for use with rats, and later adapted for use with mice. The Barnes maze design and test procedure vary across studies using mice, but the effects of variation in Barnes maze design and test procedure on learning and memory in mice have not yet been investigated. Therefore the present experiment investigates whether test procedures, such as the number of habituation trials and parameters of the probe trial (correct zone size and trial length) influence learning and memory performance on three Barnes maze designs that differed in size and the presence of a wall with intra-maze visual cues. Performance was compared across the three mazes to determine how apparatus design influences visuo-spatial cue use. The number of habituation trials and parameters of the probe trial had small effects on learning and memory performance. Apparatus design, had little effect on acquisition performance but had a significant effect on memory performance. Mice on a maze with a small diameter, external wall and intra-maze visual cues had very poor visuo-spatial memory relative to mice tested on small and large diameter mazes without a wall or intra-maze visual cues. Assessment of visuo-spatial cue use indicated that mice do not rely on visuo-spatial cues to locate the escape hole on the small-diameter maze with a wall and intra-maze visual cues, but show reliable visuo-spatial cue use on small or large diameter mazes with no wall. These results indicate that apparatus design influences search strategy use and memory performance on the Barnes maze, and that including a wall around the edge of the Barnes maze decreases visuo-spatial cue use.

  7. Fusion Reactor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2002-04-01

    The objective of SCK-CEN's programme on fusion reactor materials is to contribute to the knowledge on the radiation-induced behaviour of fusion reactor materials and components as well as to help the international community in building the scientific and technical basis needed for the construction of the future reactor. Ongoing projects include: the study of the mechanical and chemical (corrosion) behaviour of structural materials under neutron irradiation and water coolant environment; the investigation of the characteristics of irradiated first wall material such as beryllium; investigations on the management of materials resulting from the dismantling of fusion reactors including waste disposal. Progress and achievements in these areas in 2001 are discussed.

  8. New reactor type proposed

    CERN Multimedia

    2003-01-01

    "Russian scientists at the Research Institute of Nuclear Power Engineering in Moscow are hoping to develop a new reactor that will use lead and bismuth as fuel instead of uranium and plutonium" (1/2 page).

  9. Reactor Neutrino Spectra

    CERN Document Server

    Hayes, A C

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these and their associated uncertainties are crucial for neutrino oscillation studies. The spectra used to-date have been determined by either conversion of measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that makeup the spectra using modern databases as input. The uncertainties in the subdominant corrections to beta-decay plague both methods, and we provide estimates of these uncertainties. Improving on current knowledge of the antineutrino spectra from reactors will require new experiments. Such experiments would also address the so-called reactor neutrino anomaly and the possible origin of the shoulder observed in the antineutrino spectra measured in recent high-statistics reactor neutrino experiments.

  10. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2001-04-01

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given.

  11. Future Reactor Experiments

    OpenAIRE

    He, Miao

    2013-01-01

    The measurement of the neutrino mixing angle $\\theta_{13}$ opens a gateway for the next generation experiments to measure the neutrino mass hierarchy and the leptonic CP-violating phase. Future reactor experiments will focus on mass hierarchy determination and the precision measurement of mixing parameters. Mass hierarchy can be determined from the disappearance of reactor electron antineutrinos based on the interference effect of two separated oscillation modes. Relative and absolute measure...

  12. Reactor Neutrino Experiments

    OpenAIRE

    Cao, Jun

    2007-01-01

    Precisely measuring $\\theta_{13}$ is one of the highest priority in neutrino oscillation study. Reactor experiments can cleanly determine $\\theta_{13}$. Past reactor neutrino experiments are reviewed and status of next precision $\\theta_{13}$ experiments are presented. Daya Bay is designed to measure $\\sin^22\\theta_{13}$ to better than 0.01 and Double Chooz and RENO are designed to measure it to 0.02-0.03. All are heading to full operation in 2010. Recent improvements in neutrino moment measu...

  13. Department of Reactor Technology

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included.......The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included....

  14. Helias reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Beidler, C.D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Grieger, G. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Harmeyer, E. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Kisslinger, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Karulin, N. [Nuclear Fusion Institute, Moscow (Russian Federation); Maurer, W. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany); Nuehrenberg, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Rau, F. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Sapper, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Wobig, H. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    1995-10-01

    The present status of Helias reactor studies is characterised by the identification and investigation of specific issues which result from the particular properties of this type of stellarator. On the technical side these are issues related to the coil system, while physics studies have concentrated on confinement, alpha-particle behaviour and ignition conditions. The usual assumptions have been made in those fields which are common to all toroidal fusion reactors: blanket and shield, refuelling and exhaust, safety and economic aspects. For blanket and shield sufficient space has been provided, a detailed concept will be developed in future. To date more emphasis has been placed on scoping and parameter studies as opposed to fixing a specific set of parameters and providing a detailed point study. One result of the Helias reactor studies is that physical dimensions are on the same order as those of tokamak reactors. However, it should be noticed that this comparison is difficult in view of the large spectrum of tokamak reactors ranging from a small reactor like Aries, to a large device such as SEAFP. The notion that the large aspect ratio of 10 or more in Helias configurations also leads to large reactors is misleading, since the large major radius of 22 m is compensated by the average plasma radius of 1.8 m and the average coil radius of 5 m. The plasma volume of 1400 m{sup 3} is about the same as the ITER reactor and the magnetic energy of the coil system is about the same or even slightly smaller than envisaged in ITER. (orig.)

  15. INVAP's Research Reactor Designs

    OpenAIRE

    Eduardo Villarino; Alicia Doval

    2011-01-01

    INVAP, an Argentine company founded more than three decades ago, is today recognized as one of the leaders within the research reactor industry. INVAP has participated in several projects covering a wide range of facilities, designed in accordance with the requirements of our different clients. For complying with these requirements, INVAP developed special skills and capabilities to deal with different fuel assemblies, different core cooling systems, and different reactor layouts. This paper ...

  16. Final report : results of the 2006-2007 investigation of potential contamination at the former CCC/USDA facility in Barnes, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2008-08-28

    The 2006-2007 investigation of carbon tetrachloride and chloroform contamination at Barnes, Kansas, was conducted at the request of the Kansas Department of Health and Environment (KDHE). The Environmental Science Division of Argonne National Laboratory implemented the investigation on behalf of the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The overall goal of the investigation was to establish criteria for monitoring leading to potential site reclassification. The investigation objectives were to (1) determine the hydraulic gradient near the former CCC/USDA facility, (2) delineate the downgradient carbon tetrachloride plume, and (3) design and implement an expanded monitoring network at Barnes (Argonne 2006a).

  17. The reactor antineutrino anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Haser, Julia; Buck, Christian; Lindner, Manfred [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2016-07-01

    Major discoveries were made in the past few years in the field of neutrino flavour oscillation. Nuclear reactors produce a clean and intense flux of electron antineutrinos and are thus an essential neutrino source for the determination of oscillation parameters. Most currently the reactor antineutrino experiments Double Chooz, Daya Bay and RENO have accomplished to measure θ{sub 13}, the smallest of the three-flavour mixing angles. In the course of these experiments two anomalies emerged: (1) the reanalysis of the reactor predictions revealed a deficit in experimentally observed antineutrino flux, known as the ''reactor antineutrino anomaly''. (2) The high precision of the latest generation of neutrino experiments resolved a spectral shape distortion relative to the expected energy spectra. Both puzzles are yet to be solved and triggered new experimental as well as theoretical studies, with the search for light sterile neutrinos as most popular explanation for the flux anomaly. This talk outlines the two reactor antineutrino anomalies. Discussing possible explanations for their occurrence, recent and upcoming efforts to solve the reactor puzzles are highlighted.

  18. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  19. Comparison of Aviary, Barn and Conventional Cage Raising of Chickens on Laying Performance and Egg Quality

    Directory of Open Access Journals (Sweden)

    M. Ahammed

    2014-08-01

    Full Text Available This study intended to compare the productive performance of three different layer raising systems; conventional cage (CC, barn (BR and aviary (AV. The AV is welfare bestowed housing that allows free locomotion for birds within the BR. The BR allows bird’s free locomotion inside BR but without multilevel structures. Both pullets and cockerels were housed together in both AV and BR, but only pullets in CC. Seventeen weeks old Lohmann Brown Lite (n = 800 pullets were housed in AV during this study. The same age layer pullets were simultaneously assigned to either at CC or BR to compare egg production performance with AV. The duration of experiment was 40 weeks (from 21st to 60th week. There were no remarkable differences in egg production, hen day egg production (HDEP and average egg weight among three rearing systems. First 20 weeks (phase-1 average HDEP (% of AV, CC, and BR were 85.9, 88.8, 87.1 and average egg weights (g were 57.5, 59.9, and 56.9 respectively. Those of the remaining 20 weeks (phase-2 were 87.1, 87.9, 85.5 and 64.2, 63.0 62.1, respectively. Daily feed intakes (122 g, 110 g, 125 g; feed conversion ratio (2.4, 2.1, 2.5 and daily egg mass (53.9 g, 54.4 g, 52.8 g data from AV, CC, and BR were not influenced significantly by the respective raising systems. Daily feed intake of layers in both AV (124 g and BR (127 g tended to be higher than that in CC (113 g during phase-2. Overall, exterior egg quality (dirty and cracked eggs in both phases was superior in BR compared with AV and CC, whereas CC generated intermediate results. This study indicated that the HDEP per se in AV and BR were not significantly different from that in CC. The study implied that the facility depreciation cost for AV and cost for increased feed intake in AV compared to CC are believed to be critical to evaluate the cost effectiveness of egg production in AV.

  20. Maps of ITD in the nucleus laminaris of the barn owl.

    Science.gov (United States)

    Carr, Catherine; Shah, Sahil; Ashida, Go; McColgan, Thomas; Wagner, Hermann; Kuokkanen, Paula T; Kempter, Richard; Köppl, Christine

    2013-01-01

    Axons from the nucleus magnocellularis (NM) and their targets in nucleus laminaris (NL) form the circuit responsible for encoding interaural time differences (ITDs). In barn owls, NL receives bilateral inputs from NM such that axons from the ipsilateral NM enter NL dorsally, while contralateral axons enter from the ventral side. These afferents and their synapses on NL neurons generate a tone-induced local field potential, or neurophonic, that varies systematically with position in NL. From dorsal to ventral within the nucleus, the best interaural time difference (ITD) of the neurophonic shifts from contralateral space to best ITDs around 0 µs. Earlier recordings suggested that in NL, iso-delay contours ran parallel to the dorsal and ventral borders of NL (Sullivan WE, Konishi M. Proc Natl Acad Sci U S A 83:8400-8404, 1986). This axis is orthogonal to that seen in chicken NL, where a single map of ITD runs from around 0 µs ITD medially to contralateral space laterally (Köppl C, Carr CE. Biol Cyber 98:541-559, 2008). Yet the trajectories of the NM axons are similar in owl and chicken (Seidl AH, Rubel EW, Harris DM, J Neurosci 30:70-80, 2010). We therefore used clicks to measure conduction time in NL and made lesions to mark the 0 µs iso-delay contour in multiple penetrations along an isofrequency slab. Iso-delay contours were not parallel to the dorsal and ventral borders of NL; instead the 0 µs iso-delay contour shifted systematically from a dorsal position in medial NL to a ventral position in lateral NL. Could different conduction delays account for the mediolateral shift in the representation of 0 µs ITD? We measured conduction delays using the neurophonic potential and developed a simple linear model of the delay-line conduction velocity. We then raised young owls with time-delaying earplugs in one ear (Gold JI, Knudsen EI, J Neurophysiol 82:2197-2209, 1999) to examine map plasticity.

  1. Neural maps of interaural time and intensity differences in the optic tectum of the barn owl.

    Science.gov (United States)

    Olsen, J F; Knudsen, E I; Esterly, S D

    1989-07-01

    This report describes the binaural basis of the auditory space map in the optic tectum of the barn owl (Tyto alba). Single units were recorded extracellularly in ketamine-anesthetized birds. Unit tuning for interaural differences in timing and intensity of wideband noise was measured using digitally synthesized sound presented through earphones. Spatial receptive fields of the same units were measured with a free field sound source. Auditory units in the optic tectum are sharply tuned for both the azimuth and the elevation of a free field sound source. To determine the binaural cues that could be responsible for this spatial tuning, we measured in the ear canals the amplitude and phase spectra produced by a free field noise source and calculated from these measurements the interaural differences in time and intensity associated with each of 178 locations throughout the frontal hemisphere. For all frequencies, interaural time differences (ITDs) varied systematically and most strongly with source azimuth. The pattern of variation of interaural intensity differences (IIDs) depended on frequency. For low frequencies (below 4 kHz) IID varied primarily with source azimuth, whereas for high frequencies (above 5 kHz) IID varied primarily with source elevation. Tectal units were tuned for interaural differences in both time and intensity of dichotic stimuli. Changing either parameter away from the best value for the unit decreased the unit's response. The tuning of units to either parameter was sharp: the width of ITD tuning curves, measured at 50% of the maximum response with IID held constant (50% tuning width), ranged from 18 to 82 microsecs. The 50% tuning widths of IID tuning curves, measured with ITD held constant, ranged from 8 to 37 dB. For most units, tuning for ITD was largely independent of IID, and vice versa. A few units exhibited systematic shifts of the best ITD with changes in IID (or shifts of the best IID with changes in ITD); for these units, a change in

  2. Sex-linked inheritance, genetic correlations and sexual dimorphism in three melanin-based colour traits in the barn owl.

    Science.gov (United States)

    Roulin, A; Jensen, H

    2015-03-01

    Theory states that genes on the sex chromosomes have stronger effects on sexual dimorphism than genes on the autosomes. Although empirical data are not necessarily consistent with this theory, this situation may prevail because the relative role of sex-linked and autosomally inherited genes on sexual dimorphism has rarely been evaluated. We estimated the quantitative genetics of three sexually dimorphic melanin-based traits in the barn owl (Tyto alba), in which females are on average darker reddish pheomelanic and display more and larger black eumelanic feather spots than males. The plumage traits with higher sex-linked inheritance showed lower heritability and genetic correlations, but contrary to prediction, these traits showed less pronounced sexual dimorphism. Strong offspring sexual dimorphism primarily resulted from daughters not expressing malelike melanin-based traits and from sons expressing femalelike traits to similar degrees as their sisters. We conclude that in the barn owl, polymorphism at autosomal genes rather than at sex-linked genes generate variation in sexual dimorphism in melanin-based traits.

  3. Muscular Arrangement and Muscle Attachment Sites in the Cervical Region of the American Barn Owl (Tyto furcata pratincola).

    Science.gov (United States)

    Boumans, Mark L L M; Krings, Markus; Wagner, Hermann

    2015-01-01

    Owls have the largest head rotation capability amongst vertebrates. Anatomical knowledge of the cervical region is needed to understand the mechanics of these extreme head movements. While data on the morphology of the cervical vertebrae of the barn owl have been provided, this study is aimed to provide an extensive description of the muscle arrangement and the attachment sites of the muscles on the owl's head-neck region. The major cervical muscles were identified by gross dissection of cadavers of the American barn owl (Tyto furcata pratincola), and their origin, courses, and insertion were traced. In the head-neck region nine superficial larger cervical muscles of the craniocervical, dorsal and ventral subsystems were selected for analysis, and the muscle attachment sites were illustrated in digital models of the skull and cervical vertebrae of the same species as well as visualised in a two-dimensional sketch. In addition, fibre orientation and lengths of the muscles and the nature (fleshy or tendinous) of the attachment sites were determined. Myological data from this study were combined with osteological data of the same species. This improved the anatomical description of the cervical region of this species. The myological description provided in this study is to our best knowledge the most detailed documentation of the cervical muscles in a strigiform species presented so far. Our results show useful information for researchers in the field of functional anatomy, biomechanical modelling and for evolutionary and comparative studies.

  4. Response properties of neurons in the core of the central nucleus of the inferior colliculus of the barn owl.

    Science.gov (United States)

    Wagner, Hermann; Mazer, James A; von Campenhausen, Mark

    2002-04-01

    The central nucleus of the inferior colliculus (ICC) is particularly important for the processing of interaural time differences (ITDs). In the barn owl, neuronal best frequencies in a subnucleus of the ICC, the ICCcore, span the animal's entire hearing range (approximately equal to 200-10 000 Hz). This means that low-frequency ITD-sensitive ICCcore neurons in the owl can be directly compared to ITD-sensitive mammalian ICC neurons with similar best frequencies as well as to the high-frequency ITD-sensitive neurons usually studied in owls. This report represents a first attempt to systematically describe important physiological properties of ICCcore neurons in the barn owl, with particular attention to the low-frequency region (owl's physiological ITD range. ITD tuning widths were inversely correlated with neuronal best frequency. None of the ICCcore neurons studied were sensitive to interaural level differences. Monaural inputs to ICCcore cells were typically binaurally balanced, i.e. they exhibited similar response thresholds, dynamic ranges, slopes and saturation levels, for both left and right ear monaural stimulation.

  5. Muscular Arrangement and Muscle Attachment Sites in the Cervical Region of the American Barn Owl (Tyto furcata pratincola.

    Directory of Open Access Journals (Sweden)

    Mark L L M Boumans

    Full Text Available Owls have the largest head rotation capability amongst vertebrates. Anatomical knowledge of the cervical region is needed to understand the mechanics of these extreme head movements. While data on the morphology of the cervical vertebrae of the barn owl have been provided, this study is aimed to provide an extensive description of the muscle arrangement and the attachment sites of the muscles on the owl's head-neck region. The major cervical muscles were identified by gross dissection of cadavers of the American barn owl (Tyto furcata pratincola, and their origin, courses, and insertion were traced. In the head-neck region nine superficial larger cervical muscles of the craniocervical, dorsal and ventral subsystems were selected for analysis, and the muscle attachment sites were illustrated in digital models of the skull and cervical vertebrae of the same species as well as visualised in a two-dimensional sketch. In addition, fibre orientation and lengths of the muscles and the nature (fleshy or tendinous of the attachment sites were determined. Myological data from this study were combined with osteological data of the same species. This improved the anatomical description of the cervical region of this species. The myological description provided in this study is to our best knowledge the most detailed documentation of the cervical muscles in a strigiform species presented so far. Our results show useful information for researchers in the field of functional anatomy, biomechanical modelling and for evolutionary and comparative studies.

  6. a Comparison of Laser Scanning and Structure from Motion as Applied to the Great Barn at Harmondsworth, UK

    Science.gov (United States)

    Andrews, D. P.; Bedford, J.; Bryan, P. G.

    2013-07-01

    The great barn at Harmondsworth near London Heathrow airport, United Kingdom (UK), was built in 1426-7 for the Bishop of Winchester. At 58 metres long and 11.4 metres wide, it is one of the largest ever known to have been built in the UK, and the largest intact medieval timber-framed barn in England. The barn is built almost entirely of oak, although the walls rest on a low masonry sill-wall. Internally the space is divided into a central "nave" with a lower aisle to each side, and is divided along its length into 12 bays. There are three doorways on the east side. For an entirely timber-framed barn, the fabric is exceptionally well preserved. Even the external weatherboarding may be partly original. Following years of neglect, however, there are a number of on-going structural and conservation problems, so in 2011 the barn was bought by English Heritage in order to allow these needs to be addressed. English Heritage is the government agency responsible for the historic sites and buildings in the care of the state of England and is also the UK government's lead advisor on the built heritage. As one of the first steps in the conservation process the English Heritage Geospatial Imaging and Imaging & Visualisation teams undertook a four-day campaign of survey data collection. This took the form of laser scanning of the interior and exterior of the barn plus the acquisition of photography of the exterior elevations to be used with structure from motion (SFM) software. A comparison of the results of these complimentary yet potentially competing technologies will be given, as well as an evaluation of when they can be successfully used together. This paper will describe the procedures and problems involved with collecting the survey data and its subsequent analysis. The laser scanning was undertaken using a FARO Focus 3D phase based instrument. Approximately 60 scans were acquired in order to provide as comprehensive as possible coverage given the site circumstances. A

  7. Barns deltakelse og tidlig innsats: et pedagogisk bidrag til forståelse av tidlig innsats i norske barnehager

    Directory of Open Access Journals (Sweden)

    Stine Vik

    2014-11-01

    Full Text Available Tidlig innsats har fått en betydelig posisjon i det pedagogisk arbeidet i norske barnehager de siste årene. Ifølge nasjonale styringsdokumenter som beskriver tidlig innsats er bruk av standardiserte programmer og kartlegging for å identifisere og forebygge vansker på et tidlig tidspunkt i barns liv en del av satsingen(KD, 2006, 2008. Det er imidlertid reist kritikk av denne utviklingen(Arnesen, 2012; Hausstätter 2009; Pettersvold & Østrem, 2012. Artikkelen drøfter hvordan tidlig innsats i barnehagen kan tolkes i samsvar med barns rett til medvirkning. Videre diskuteres utfordringer for implementering av programmer for tidlig innsats i norske barnehager.Early intervention has been given a significant position directing work in Norwegian kindergartens resent years. According to national policy documents for early intervention, standardized programs are posed to identify and prevent difficulties at an early stage in children’s lives (NOU, 2009; St.meld nr. 16 (2006-2007. However critique has been raised against directives given from the national level (in Arnesen, 2012; Haustätter, 2009; Pettersvoll & Østrem, 2012. This article argues that early intervention is in danger of becoming an instrumental mistake, as described by Skjervheim in the 60-70s, that does not take into consideration the ethical obligation of treating children as ends not only as means. To avoid the object-orientation children’s perspectives should be acknowledged in the processes of intervening early.

  8. Foraging at the edge of the world: low-altitude, high-speed manoeuvering in barn swallows.

    Science.gov (United States)

    Warrick, Douglas R; Hedrick, Tyson L; Biewener, Andrew A; Crandell, Kristen E; Tobalske, Bret W

    2016-09-26

    While prior studies of swallow manoeuvering have focused on slow-speed flight and obstacle avoidance in still air, swallows survive by foraging at high speeds in windy environments. Recent advances in field-portable, high-speed video systems, coupled with precise anemometry, permit measures of high-speed aerial performance of birds in a natural state. We undertook the present study to test: (i) the manner in which barn swallows (Hirundo rustica) may exploit wind dynamics and ground effect while foraging and (ii) the relative importance of flapping versus gliding for accomplishing high-speed manoeuvers. Using multi-camera videography synchronized with wind-velocity measurements, we tracked coursing manoeuvers in pursuit of prey. Wind speed averaged 1.3-2.0 m s(-1) across the atmospheric boundary layer, exhibiting a shear gradient greater than expected, with instantaneous speeds of 0.02-6.1 m s(-1) While barn swallows tended to flap throughout turns, they exhibited reduced wingbeat frequency, relying on glides and partial bounds during maximal manoeuvers. Further, the birds capitalized on the near-earth wind speed gradient to gain kinetic and potential energy during both flapping and gliding turns; providing evidence that such behaviour is not limited to large, fixed-wing soaring seabirds and that exploitation of wind gradients by small aerial insectivores may be a significant aspect of their aeroecology.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'.

  9. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    Energy Technology Data Exchange (ETDEWEB)

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  10. REACTOR GROUT THERMAL PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  11. Scaleable, High Efficiency Microchannel Sabatier Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A Microchannel Sabatier Reactor System (MSRS) consisting of cross connected arrays of isothermal or graded temperature reactors is proposed. The reactor array...

  12. Upper limit on the cross section for reactor antineutrinos changing 22Na decay rates

    CERN Document Server

    de Meijer, R J

    2014-01-01

    In this paper we present results of a long-term observation of the decay of 22Na in the presence of a nuclear fission reactor. The measurements were made outside the containment wall of and underneath the Koeberg nuclear power plant near Cape Town, South Africa. Antineutrino fluxes ranged from ~5*10^11 to 1.6*10^13 cm^-2 s^-1 during this period. We show that the coincidence summing technique provides a sensitive tool to measure a change in the total decay constant as well as the branching ratio between EC and beta+ decay of 22Na to the first excited state in 22Ne. We observe a relative change in count rate between reactor-ON and reactor-OFF equal to (-0.51+/-0.11)*10^-4. After evaluating possible systematic uncertainties we conclude that the effect is either due to a hidden instrumental cause or due to an interaction between antineutrinos and the 22Na nucleus. An upper limit of ~0.03 barn has been deduced for observing any change in the decay rate of 22Na due to antineutrino interactions.

  13. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Takeshi; Iida, Masaaki; Moriki, Yasuyuki

    1994-10-18

    A reactor core is divided into a plurality of coolants flowrate regions, and electromagnetic pumps exclusively used for each of the flowrate regions are disposed to distribute coolants flowrates in the reactor core. Further, the flowrate of each of the electromagnetic pumps is automatically controlled depending on signals from a temperature detector disposed at the exit of the reactor core, so that the flowrate of the region can be controlled optimally depending on the burning of reactor core fuels. Then, the electromagnetic pumps disposed for every divided region are controlled respectively, so that the coolants flowrate distribution suitable to each of the regions can be attained. Margin for fuel design is decreased, fuels are used effectively, as well as an operation efficiency can be improved. Moreover, since the electromagnetic pump has less flow resistance compared with a mechanical type pump, and flow resistance of the reactor core flowrate control mechanism is eliminated, greater circulating flowrate can be ensured after occurrence of accident in a natural convection using a buoyancy of coolants utilizable for after-heat removal as a driving force. (N.H.).

  14. Reactor Structural Materials: Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Chaouadi, R

    2000-07-01

    The objectives of SCK-CEN's R and D programme on Rector Pressure Vessel (RPV) Steels are:(1) to complete the fracture toughness data bank of various reactor pressure vessel steels by using precracked Charpy specimens that were tested statically as well as dynamically; (2) to implement the enhanced surveillance approach in a user-friendly software; (3) to improve the existing reconstitution technology by reducing the input energy (short cycle welding) and modifying the stud geometry. Progress and achievements in 1999 are reported.

  15. "Det är ett vanligt barn, även om det är lite speciellt" : Några förskollärares syn på begreppet barn i behov av särskilt stöd

    OpenAIRE

    Vuento, Noora; Waldenström, Inger

    2013-01-01

    Syftet med denna studie var att undersöka hur några förskollärare ser på begreppet barn i behov av särskilt stöd och vilka barn som omfattas av begreppet enligt dem. De forskningsfrågor vi ställde var hur förskollärare definierar begreppet barn i behov av särskilt stöd, hur förskollärare gör bedömningen av vilka barn som är i behov av särskilt stöd samt hur förskollärare tolkar förskolans uppdrag när det gäller barn i behov av särskilt stöd. För att undersöka dessa frågor använde vi oss av kv...

  16. Study of $ \\bar{p} $ and $ \\bar{n} $ annihilations at LEAR with OBELIX, a large acceptance and high resolution detector based on the Open Axial Field Spectrometer

    CERN Multimedia

    2002-01-01

    % PS201 Study of $\\bar{p}$ and $\\bar{n}$ annihilations at LEAR with OBELIX, a large acceptance and high resolution detector based on the Open Axial Field Spectrometer \\\\ \\\\OBELIX is designed to study exclusive final states of antiproton and antineutron annihilations at low energies with protons and nuclei. \\\\ \\\\The physics motivations of the experiment are:\\\\ \\\\\\begin{itemize} \\item (gg, ggg), hybrids ($ q \\bar{q} g $), multiquarks ($ q q \\bar{q} \\bar{q} $) and light mesons ($ q \\bar{q} $) produced in $ N \\bar{N} $ annihilations and study of their spectroscopy and decays. Also broad structures will be searched for by comparing identical decay modes in exclusive final states of the same type occuring from initial states with different angular momentum or isospin. \\item Study of the dynamics of $ N \\bar{N} $ interactions and of the dependence of the final and intermediate resonant states of annihilation upon the quantum numbers of the initial $ N \\bar{N} $ state (angular momentum: S and P-wave in $\\bar{p}p $ at...

  17. Tests of the Aversive Summation Hypothesis in Rats: Effects of Restraint Stress on Consummatory Successive Negative Contrast and Extinction in the Barnes Maze

    Science.gov (United States)

    Ortega, Leonardo A.; Prado-Rivera, Mayerli A.; Cardenas-Poveda, D. Carolina; McLinden, Kristina A.; Glueck, Amanda C.; Gutierrez, German; Lamprea, Marisol R.; Papini, Mauricio R.

    2013-01-01

    The present research explored the effects of restraint stress on two situations involving incentive downshift: consummatory successive negative contrast (cSNC) and extinction of escape behavior in the Barnes maze. First, Experiment 1 confirmed that the restraint stress procedure used in these experiments increased levels of circulating…

  18. Dairy barns and roll-over protection on farm tractors: work environment impacts on the adoption of roll-over protective structures.

    Science.gov (United States)

    Kelsey, T W; Dennis, J W; Jenkins, P L

    1994-04-01

    A mailed survey of one group of dairy farmers supports the informal perception that roll-over protective structure (ROPS)-equipped tractors are considered unusable for in-barn tasks. This attitude must be addressed in order to achieve greater use of safety equipment.

  19. Operation of Reactor

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    3.1 Annual Report of SPR Operation Chu Shaochu Having overseen by National Nuclear Safety Administration and specialists, the reactor restarted up successfully after Safety renovation on April 16, 1996. In August 1996 the normal operation of SPR was approved by the authorities of Naitonal Nuclear Safety Administration. 1 Operation status In 1996, the reactor operated safely for 40 d and the energy released was about 137.3 MW·d. The operation status of SPR is shown in table 1. The reactor started up to higher power (power more than 1 MW) and lower power (for physics experiments) 4 times and 14 times respectively. Measurement of control rod efficiency and other measurement tasks were 2 times and 5 times respectively.

  20. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  1. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  2. An Overview of Reactor Concepts, a Survey of Reactor Designs.

    Science.gov (United States)

    1985-02-01

    Public Affairs Office and is releasaole to the National Technical Information Services (NTIS). At NTIS, it will be available to the general public...Reactors that use deu- terium (heavy water) as a coolant can use natural uranium as a fuel. The * Canadian reactor, CANDU , utilizes this concept...reactor core at the top and discharged at the Dotton while the reactor is in operation. The discharged fuel can then b inspected to see if it can De used

  3. Oscillatory flow chemical reactors

    Directory of Open Access Journals (Sweden)

    Slavnić Danijela S.

    2014-01-01

    Full Text Available Global market competition, increase in energy and other production costs, demands for high quality products and reduction of waste are forcing pharmaceutical, fine chemicals and biochemical industries, to search for radical solutions. One of the most effective ways to improve the overall production (cost reduction and better control of reactions is a transition from batch to continuous processes. However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat and mass transfer and narrow residence time distribution. The oscillatory flow reactors (OFR are newer type of tube reactors which can offer solution by providing continuous operation with approximately plug flow pattern, low shear stress rates and enhanced mass and heat transfer. These benefits are the result of very good mixing in OFR achieved by vortex generation. OFR consists of cylindrical tube containing equally spaced orifice baffles. Fluid oscillations are superimposed on a net (laminar flow. Eddies are generated when oscillating fluid collides with baffles and passes through orifices. Generation and propagation of vortices create uniform mixing in each reactor cavity (between baffles, providing an overall flow pattern which is close to plug flow. Oscillations can be created by direct action of a piston or a diaphragm on fluid (or alternatively on baffles. This article provides an overview of oscillatory flow reactor technology, its operating principles and basic design and scale - up characteristics. Further, the article reviews the key research findings in heat and mass transfer, shear stress, residence time distribution in OFR, presenting their advantages over the conventional reactors. Finally, relevant process intensification examples from pharmaceutical, polymer and biofuels industries are presented.

  4. Perspectives on reactor safety

    Energy Technology Data Exchange (ETDEWEB)

    Haskin, F.E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Camp, A.L. [Sandia National Labs., Albuquerque, NM (United States)

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  5. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2002-04-01

    The activities of SCK-CEN's Reactor Materials Research Department for 2001 are summarised. The objectives of the department are: (1) to evaluate the integrity and behaviour of structural materials used in nuclear power industry; (2) to conduct research to unravel and understand the parameters that determine the material behaviour under or after irradiation; (3) to contribute to the interpretation, the modelling of the material behaviour and to develop and assess strategies for optimum life management of nuclear power plant components. The programmes within the department are focussed on studies concerning (1) Irradiation Assisted Stress Corrosion Cracking (IASCC); (2) nuclear fuel; and (3) Reactor Pressure Vessel Steel.

  6. Fusion Reactor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2000-07-01

    SCK-CEN's research and development programme on fusion reactor materials includes: (1) the study of the mechanical behaviour of structural materials under neutron irradiation (including steels, inconel, molybdenum, chromium); (2) the determination and modelling of the characteristics of irradiated first wall materials such as beryllium; (3) the detection of abrupt electrical degradation of insulating ceramics under high temperature and neutron irradiation; (4) the study of the dismantling and waste disposal strategy for fusion reactors.; (5) a feasibility study for the testing of blanket modules under neutron radiation. Main achievements in these topical areas in the year 1999 are summarised.

  7. Continuous measurement of reticuloruminal pH values in dairy cows during the transition period from barn to pasture feeding using an indwelling wireless data transmitting unit.

    Science.gov (United States)

    Gasteiner, J; Horn, M; Steinwidder, A

    2015-04-01

    This study was performed to investigate the effect of the transition from barn feeding to pasture on the pattern of reticuloruminal pH values in 8 multiparous dairy cows. A indwelling wireless data transmitting system for pH measurement was given to 8 multiparous cows orally. Reticuloruminal pH values were measured every 600 s over a period of 42 days. After 7 days of barn feeding (period 1), all of the animals were pastured with increasing grazing times from 2 to 7 h/day over 7 days (period 2). From day 15 to day 21 (period 3), the cows spent 7 h/day on pasture. Beginning on day 22, the animals had 20 h/day access to pasture (day and night grazing). To study reticuloruminal adaptation to pasture feeding, the phase of day and night grazing was subdivided into another 3 weekly periods (periods 4-6). Despite a mild transition period from barn feeding to pasture, significant effects on reticuloruminal pH values were observed. During barn feeding, the mean reticuloruminal pH value for all of the cows was 6.44 ± 0.14, and the pH values decreased significantly (p pH values increased again (pH 6.25 ± 0.22; pH 6.31 ± 0.17; pH 6.37 ± 0.16). Our results showed that the animals had significantly lowered reticuloruminal pH during the periods of feed transition from barn to pasture feeding. Despite these significant changes, the decrease was not harmful, as indicated by data of feed intake and milk production.

  8. High Flux Isotope Reactor (HFIR)

    Data.gov (United States)

    Federal Laboratory Consortium — The HFIR at Oak Ridge National Laboratory is a light-water cooled and moderated reactor that is the United States’ highest flux reactor-based neutron source. HFIR...

  9. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  10. Reactor operation safety information document

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  11. REACTOR FUEL ELEMENTS TESTING CONTAINER

    Science.gov (United States)

    Whitham, G.K.; Smith, R.R.

    1963-01-15

    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  12. Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. [eds.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  13. WATER BOILER REACTOR

    Science.gov (United States)

    King, L.D.P.

    1960-11-22

    As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.

  14. MULTISTAGE FLUIDIZED BED REACTOR

    Science.gov (United States)

    Jonke, A.A.; Graae, J.E.A.; Levitz, N.M.

    1959-11-01

    A multistage fluidized bed reactor is described in which each of a number of stages is arranged with respect to an associated baffle so that a fluidizing gas flows upward and a granular solid downward through the stages and baffles, whereas the granular solid stopsflowing downward when the flow of fluidizing gas is shut off.

  15. Fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  16. Integral Fast Reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.

    1986-01-01

    The Integral Fast Reactor (IFR) is an innovative LMR concept, being developed at Argonne National Laboratory, that fully exploits the inherent properties of liquid metal cooling and metallic fuel to achieve breakthroughs in economics and inherent safety. This paper describes key features and potential advantages of the IFR concept, technology development status, fuel cycle economics potential, and future development path.

  17. The First Reactor.

    Science.gov (United States)

    Department of Energy, Washington, DC.

    On December 2, 1942, in a racquet court underneath the West Stands of Stagg Field at the University of Chicago, a team of scientists led by Enrico Fermi created the first controlled, self-sustaining nuclear chain reaction. This updated and revised story of the first reactor (or "pile") is based on postwar interviews (as told to Corbin…

  18. Thermal Reactor Safety

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  19. Chromatographic and Related Reactors.

    Science.gov (United States)

    1988-01-07

    special information about effects of surface heteroge- neity in the methanation reaction. Studies of an efficient multicolumn assembly for measuring...of organic basic catalysts such as pyridine and 4-methylpicoline. It was demonstrated that the chromatographic reactor gave special information about...Programmed Reaction to obtain special information about surface heterogeneity in the methanation reaction. Advantages of stopped flow over steady state

  20. New concepts for shaftless recycle reactors

    Energy Technology Data Exchange (ETDEWEB)

    Berty, J.M.; Berty, I.J.

    1987-01-01

    Berty Reaction Engineers, Ltd. (BREL) is developing two new laboratory recycle reactors, the ROTOBERTY and the TURBOBERTY. These new reactors are basically improved versions of the original Berty reactor. To understand why the reactors have the features that they do, it is first necessary to briefly review laboratory reactors in general and specifically the original Berty reactor.

  1. Brazilian multipurpose reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The Brazilian Multipurpose Reactor (RMB) Project is an action of the Federal Government, through the Ministry of Science Technology and Innovation (MCTI) and has its execution under the responsibility of the Brazilian National Nuclear Energy Commission (CNEN). Within the CNEN, the project is coordinated by the Research and Development Directorate (DPD) and developed through research units of this board: Institute of Nuclear Energy Research (IPEN); Nuclear Engineering Institute (IEN); Centre for Development of Nuclear Technology (CDTN); Regional Center of Nuclear Sciences (CRCN-NE); and Institute of Radiation Protection and Dosimetry (IRD). The Navy Technological Center in Sao Paulo (CTMSP) and also the participation of other research centers, universities, laboratories and companies in the nuclear sector are important and strategic partnerships. The conceptual design and the safety analysis of the reactor and main facilities, related to nuclear and environmental licensing, are performed by technicians of the research units of DPD / CNEN. The basic design was contracted to engineering companies as INTERTHECNE from Brazil and INVAP from Argentine. The research units from DPD/CNEN are also responsible for the design verification on all engineering documents developed by the contracted companies. The construction and installation should be performed by specific national companies and international partnerships. The Nuclear Reactor RMB will be a open pool type reactor with maximum power of 30 MW and have the OPAL nuclear reactor of 20 MW, built in Australia and designed by INVAP, as reference. The RMB reactor core will have a 5x5 configuration, consisting of 23 elements fuels (EC) of U{sub 3}Si{sub 2} dispersion-type Al having a density of up to 3.5 gU/cm{sup 3} and enrichment of 19.75% by weight of {sup 23{sup 5}}U. Two positions will be available in the core for materials irradiation devices. The main objectives of the RMB Reactor and the other nuclear and radioactive

  2. Sex-related effects of an immune challenge on growth and begging behavior of barn swallow nestlings.

    Science.gov (United States)

    Romano, Andrea; Rubolini, Diego; Caprioli, Manuela; Boncoraglio, Giuseppe; Ambrosini, Roberto; Saino, Nicola

    2011-01-01

    Parent-offspring conflicts lead the offspring to evolve reliable signals of individual quality, including parasite burden, which may allow parents to adaptively modulate investment in the progeny. Sex-related variation in offspring reproductive value, however, may entail differential investment in sons and daughters. Here, we experimentally manipulated offspring condition in the barn swallow (Hirundo rustica) by subjecting nestlings to an immune challenge (injection with bacterial lipopolysaccharide, LPS) that simulates a bacterial infection, and assessed the effects on growth, feather quality, expression of morphological (gape coloration) and behavioral (posture) begging displays involved in parent-offspring communication, as well as on food allocation by parents. Compared to sham-injected controls, LPS-treated chicks suffered a depression of body mass and a reduction of palate color saturation. In addition, LPS treatment resulted in lower feather quality, with an increase in the occurrence of fault bars on wing feathers. The color of beak flanges, feather growth and the intensity of postural begging were affected by LPS treatment only in females, suggesting that chicks of either sex are differently susceptible to the immune challenge. However, irrespective of the effects of LPS, parents equally allocated food among control and challenged offspring both under normal food provisioning and after a short period of food deprivation of the chicks. These results indicate that bacterial infection and the associated immune response entail different costs to offspring of either sex, but a decrease in nestling conditions does not affect parental care allocation, possibly because the barn swallow adopts a brood-survival strategy. Finally, we showed that physiological stress induced by pathogens impairs plumage quality, a previously neglected major negative impact of bacterial infection which could severely affect fitness, particularly among long-distance migratory birds.

  3. Modeling Chemical Reactors I: Quiescent Reactors

    CERN Document Server

    Michoski, C E; Schmitz, P G

    2010-01-01

    We introduce a fully generalized quiescent chemical reactor system in arbitrary space $\\vdim =1,2$ or 3, with $n\\in\\mathbb{N}$ chemical constituents $\\alpha_{i}$, where the character of the numerical solution is strongly determined by the relative scaling between the local reactivity of species $\\alpha_{i}$ and the local functional diffusivity $\\mathscr{D}_{ij}(\\alpha)$ of the reaction mixture. We develop an operator time-splitting predictor multi-corrector RK--LDG scheme, and utilize $hp$-adaptivity relying only on the entropy $\\mathscr{S}_{\\mathfrak{R}}$ of the reactive system $\\mathfrak{R}$. This condition preserves these bounded nonlinear entropy functionals as a necessarily enforced stability condition on the coupled system. We apply this scheme to a number of application problems in chemical kinetics; including a difficult classical problem arising in nonequilibrium thermodynamics known as the Belousov-Zhabotinskii reaction where we utilize a concentration-dependent diffusivity tensor $\\mathscr{D}_{ij}(...

  4. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    Science.gov (United States)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  5. Reactor monitoring using antineutrino detectors

    Science.gov (United States)

    Bowden, N. S.

    2011-08-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactor as part of International Atomic Energy Agency (IAEA) and/or other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway worldwide.

  6. Reactor vessel support system. [LMFBR

    Science.gov (United States)

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  7. Methanogenesis in Thermophilic Biogas Reactors

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    1995-01-01

    Methanogenesis in thermophilic biogas reactors fed with different wastes is examined. The specific methanogenic activity with acetate or hydrogen as substrate reflected the organic loading of the specific reactor examined. Increasing the loading of thermophilic reactors stabilized the process...... as indicated by a lower concentration of volatile fatty acids in the effluent from the reactors. The specific methanogenic activity in a thermophilic pilot-plant biogas reactor fed with a mixture of cow and pig manure reflected the stability of the reactor. The numbers of methanogens counted by the most...... against Methanothrix soehngenii or Methanothrix CALS-I in any of the thermophilic biogas reactors examined. Studies using 2-14C-labeled acetate showed that at high concentrations (more than approx. 1 mM) acetate was metabolized via the aceticlastic pathway, transforming the methyl-group of acetate...

  8. Compact fusion reactors

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Fusion research is currently to a large extent focused on tokamak (ITER) and inertial confinement (NIF) research. In addition to these large international or national efforts there are private companies performing fusion research using much smaller devices than ITER or NIF. The attempt to achieve fusion energy production through relatively small and compact devices compared to tokamaks decreases the costs and building time of the reactors and this has allowed some private companies to enter the field, like EMC2, General Fusion, Helion Energy, Lawrenceville Plasma Physics and Lockheed Martin. Some of these companies are trying to demonstrate net energy production within the next few years. If they are successful their next step is to attempt to commercialize their technology. In this presentation an overview of compact fusion reactor concepts is given.

  9. MEANS FOR COOLING REACTORS

    Science.gov (United States)

    Wheeler, J.A.

    1957-11-01

    A design of a reactor is presented in which the fuel elements may be immersed in a liquid coolant when desired without the necessity of removing them from the reactor structure. The fuel elements, containing the fissionable material are in plate form and are disposed within spaced slots in a moderator material, such as graphite to form the core. Adjacent the core is a tank containing the liquid coolant. The fuel elements are mounted in spaced relationship on a rotatable shaft which is located between the core and the tank so that by rotation of the shaft the fuel elements may be either inserted in the slots in the core to sustain a chain reaction or immersed in the coolant.

  10. Integrated Microfluidic Reactors.

    Science.gov (United States)

    Lin, Wei-Yu; Wang, Yanju; Wang, Shutao; Tseng, Hsian-Rong

    2009-12-01

    Microfluidic reactors exhibit intrinsic advantages of reduced chemical consumption, safety, high surface-area-to-volume ratios, and improved control over mass and heat transfer superior to the macroscopic reaction setting. In contract to a continuous-flow microfluidic system composed of only a microchannel network, an integrated microfluidic system represents a scalable integration of a microchannel network with functional microfluidic modules, thus enabling the execution and automation of complicated chemical reactions in a single device. In this review, we summarize recent progresses on the development of integrated microfluidics-based chemical reactors for (i) parallel screening of in situ click chemistry libraries, (ii) multistep synthesis of radiolabeled imaging probes for positron emission tomography (PET), (iii) sequential preparation of individually addressable conducting polymer nanowire (CPNW), and (iv) solid-phase synthesis of DNA oligonucleotides. These proof-of-principle demonstrations validate the feasibility and set a solid foundation for exploring a broad application of the integrated microfluidic system.

  11. Reactor Neutrino Spectra

    OpenAIRE

    Hayes, A. C.; Vogel, Petr

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these spectra and their associated uncertainties is crucial for neutrino oscillation studies. The spectra used to date have been determined either by converting measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that make up the spectra, using modern databases as input. The uncertainties in the subdominant corrections to β-decay plague both methods, and we ...

  12. REACTOR MODERATOR STRUCTURE

    Science.gov (United States)

    Greenstreet, B.L.

    1963-12-31

    A system for maintaining the alignment of moderator block structures in reactors is presented. Integral restraining grids are placed between each layer of blocks in the moderator structure, at the top of the uppermost layer, and at the bottom of the lowermost layer. Slots are provided in the top and bottom surfaces of the moderator blocks so as to provide a keying action with the grids. The grids are maintained in alignment by vertical guiding members disposed about their peripheries. (AEC)

  13. BOILER-SUPERHEATED REACTOR

    Science.gov (United States)

    Heckman, T.P.

    1961-05-01

    A nuclear power reactor of the type in which a liquid moderator-coolant is transformed by nuclear heating into a vapor that may be used to drive a turbo- generator is described. The core of this reactor comprises a plurality of freely suspended tubular fuel elements, called fuel element trains, within which nonboiling pressurized liquid moderator-coolant is preheated and sprayed through orifices in the walls of the trains against the outer walls thereof to be converted into vapor. Passage of the vapor ovcr other unwetted portions of the outside of the fuel elements causes the steam to be superheated. The moderatorcoolant within the fuel elements remains in the liqUid state, and that between the fuel elements remains substantiaily in the vapor state. A unique liquid neutron-absorber control system is used. Advantages expected from the reactor design include reduced fuel element failure, increased stability of operation, direct response to power demand, and circulation of a minimum amount of liquid moderatorcoolant. (A.G.W.)

  14. The OPAL reactor

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.; Irwin, T. [Australian Nuclear Science and Technology Organisation, Sydney (Australia); Ordonez, J.P. [INVAP SE, Bariloche (Argentina)

    2007-07-01

    The project to provide a replacement for Australia's HIFAR reactor began with governmental approval in September 1997 and reached its latest milestone with the achievement of the first full power operation of the OPAL reactor in November 2006. OPAL is a pool-type reactor with a thermal power of 20 MW and a fuel enrichment maximum of 20 per cent. This has been a successful project for both ANSTO (Australian Nuclear Science and Technology Organisation) and the contractor INVAP SE. This project was characterised by extensive interaction with the project's stake-holders during project definition and the use of a performance-based turnkey contract which gave the contractor the maximum opportunity to optimise the design to achieve performance and cost effectiveness. The contactor provided significant in-house resources as well as capacity to manage an international team of suppliers and sub-contractors. A key contributor to the project's successful outcomes has been the development and maintenance of an excellent working relationship between ANSTO and INVAP project teams. Commissioning was undertaken in accordance with the IAEA recommended stages. This paper presents the approaches used to define the project requirements, to choose the supplier and to deliver the project. The main results of hot commissioning are reviewed and the problems encountered examined. Operational experience since hot commissioning is also reviewed.

  15. Nuclear research reactors in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Anna Paula Leite; Mesquita, Amir Zacarias, E-mail: aplc@cdtn.b, E-mail: amir@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The rising concerns about global warming and energy security have spurred a revival of interest in nuclear energy, giving birth to a 'nuclear power renaissance' in several countries in the world. Particularly in Brazil, in the recent years, the nuclear power renaissance can be seen in the actions that comprise its nuclear program, summarily the increase of the investments in nuclear research institutes and the government target to design and build the Brazilian Multipurpose research Reactor (BMR). In the last 50 years, Brazilian research reactors have been used for training, for producing radioisotopes to meet demands in industry and nuclear medicine, for miscellaneous irradiation services and for academic research. Moreover, the research reactors are used as laboratories to develop technologies in power reactors, which are evaluated today at around 450 worldwide. In this application, those reactors become more viable in relation to power reactors by the lowest cost, by the operation at low temperatures and, furthermore, by lower demand for nuclear fuel. In Brazil, four research reactors were installed: the IEA-R1 and the MB-01 reactors, both at the Instituto de Pesquisas Energeticas Nucleares (IPEN, Sao Paulo); the Argonauta, at the Instituto de Engenharia Nuclear (IEN, Rio de Janeiro) and the IPR-R1 TRIGA reactor, at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN, Belo Horizonte). The present paper intends to enumerate the characteristics of these reactors, their utilization and current academic research. Therefore, through this paper, we intend to collaborate on the BMR project. (author)

  16. Nuclear research reactors in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Anna Paula Leite; Mesquita, Amir Zacarias, E-mail: aplc@cdtn.b, E-mail: amir@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The rising concerns about global warming and energy security have spurred a revival of interest in nuclear energy, giving birth to a 'nuclear power renaissance' in several countries in the world. Particularly in Brazil, in the recent years, the nuclear power renaissance can be seen in the actions that comprise its nuclear program, summarily the increase of the investments in nuclear research institutes and the government target to design and build the Brazilian Multipurpose research Reactor (BMR). In the last 50 years, Brazilian research reactors have been used for training, for producing radioisotopes to meet demands in industry and nuclear medicine, for miscellaneous irradiation services and for academic research. Moreover, the research reactors are used as laboratories to develop technologies in power reactors, which are evaluated today at around 450 worldwide. In this application, those reactors become more viable in relation to power reactors by the lowest cost, by the operation at low temperatures and, furthermore, by lower demand for nuclear fuel. In Brazil, four research reactors were installed: the IEA-R1 and the MB-01 reactors, both at the Instituto de Pesquisas Energeticas Nucleares (IPEN, Sao Paulo); the Argonauta, at the Instituto de Engenharia Nuclear (IEN, Rio de Janeiro) and the IPR-R1 TRIGA reactor, at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN, Belo Horizonte). The present paper intends to enumerate the characteristics of these reactors, their utilization and current academic research. Therefore, through this paper, we intend to collaborate on the BMR project. (author)

  17. Modern embalming, circulation of fluids, and the voyage through the human arterial system: Carl L. Barnes and the culture of immortality in America.

    Science.gov (United States)

    Podgorny, Irina

    2011-01-01

    By considering the work of American embalmer, lawyer, and physician Carl Lewis Barnes (1872-1927), this paper analyzes the emergence of modern embalming in America. Barnes experimented with and exhibited the techniques by which embalming fluids travelled into the most remote cavities of the human body. In this sense, modem embalmers based their skills and methods on experimental medicine, turning the anatomy of blood vessels, physiology of circulation, and composition of blood into a circuit that allowed embalming fluids to move throughout the corpse. Embalmers in the late 19th century took ownership of the laws of hydrodynamics and the physiology of blood circulation to market their fluids and equipment, thus playing the role of physiologists of death, performing and demonstrating physiological experiments with dead bodies.

  18. Phylogenetic systematics of Barn Owl (Tyto alba (Scopoli, 1769 complex inferred from mitochondrial rDNA (16S rRNA taxonomic implication

    Directory of Open Access Journals (Sweden)

    Mansour Aliabadian

    2012-09-01

    Full Text Available The Barn owl, Tyto alba (Scopoli, 1769, occurs worldwide and shows a considerable amount of morphological and geographical variations, leading to the recognition of many subspecies throughout the world. Yet, no comprehensive study has not been done on this species. Data from mitochondrial gene (16S Ribosomal RNA (16S with 569 bp length were analyzed for 41 individuals around the world. Maximum likelihood (ML, maximum parsimony (MP and Bayesian analysis showed two distinct clades including alba clad (old world and furcata clad (new world. The amount of genetic variation within each of these clades ranged from 0.5-1.7 but variation between clades was 3.7. This data may suggest that Barn owls of the Old World may be a separate species from those of the New World.

  19. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic

  20. Barn owl (Tyto alba predation on small mammals and its role in the control of hantavirus natural reservoirs in a periurban area in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    L. Magrini

    Full Text Available The aim of this study was to inventory the species of small mammals in Uberlândia, Minas Gerais, Brazil, based on regurgitated pellets of the barn owl and to compare the frequency of rodent species in the diet and in the environment. Since in the region there is a high incidence of hantavirus infection, we also evaluate the importance of the barn owl in the control of rodents that transmit the hantavirus. Data on richness and relative abundance of rodents in the municipality were provided by the Centro de Controle de Zoonoses, from three half-yearly samplings with live traps. In total, 736 food items were found from the analysis of 214 pellets and fragments. Mammals corresponded to 86.0% of food items and were represented by one species of marsupial (Gracilinanus agilis and seven species of rodents, with Calomys tener (70.9% and Necromys lasiurus (6.7% being the most frequent. The proportion of rodent species in barn owl pellets differed from that observed in trap samplings, with Calomys expulsus, C. tener and Oligoryzomys nigripes being consumed more frequently than expected. Although restricted to a single place and based on few individuals, the present study allowed the inventory of eight species of small mammals in Uberlândia. The comparison of the relative frequencies of rodent species in the diet and in the environment indicated selectivity. The second most preyed upon species was N. lasiurus, the main hantavirus reservoir in the Cerrado biome. In this way, the barn owl might play an important role in the control of this rodent in the region, contributing to the avoidance of a higher number of cases of hantavirus infection.

  1. Hjertestop hos barn som følge af knapbatteri i øsofagus kompliceret med aorto-øsofageal fistel

    DEFF Research Database (Denmark)

    Mortensen, Anette; Hansen, Nikolaj Friis; Schiødt, Ole Mikael

    2009-01-01

    Indtagelse af knapbatteri kan medføre alvorlige komplikationer, såfremt det sidder i øsofagus. Denne kasuistik omhandler et tilfælde med et 14 måneder gammelt barn, der forblødte som følge af aorto-øsofagealfistel, der var forårsaget af et fastsiddende lithium-knapbatteri i øsofagus. Endvidere ge...

  2. Behavioral responses to frequency specific head related transfer functions as filtered by the facial ruff in the Barn owl (Tyto alba)

    OpenAIRE

    Hausmann, Elena Laura

    2010-01-01

    The barn owl is, due to its numerous morphological and neuronal adaptations to sound localization, a long-established model animal for the auditory system. Besides extensive research on the topic within the last decades, it is still unclear how direction- and frequency-dependent physical cues (interaural time differences (ITDs), level differences (ILDs) and monaural spectra) contribute to sound localization especially in the elevational plane. A further open question is to what extent frequen...

  3. Phylogenetic systematics of Barn Owl (Tyto alba (Scopoli, 1769)) complex inferred from mitochondrial rDNA (16S rRNA) taxonomic implication

    OpenAIRE

    2012-01-01

    The Barn owl, Tyto alba (Scopoli, 1769), occurs worldwide and shows a considerable amount of morphological and geographical variations, leading to the recognition of many subspecies throughout the world. Yet, no comprehensive study has not been done on this species. Data from mitochondrial gene (16S Ribosomal RNA (16S)) with 569 bp length were analyzed for 41 individuals around the world. Maximum likelihood (ML), maximum parsimony (MP) and Bayesian analysis showed two distinct clades includin...

  4. New reactors for laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Berty, J.M.

    1978-02-01

    Recent developments in design of laboratory and bench-scale reactors reflect mostly the developments in reaction engineering; that is the improved understanding of physical and chemical rate limiting processes, their interactions, and their effects on commercial-scale reactor performance. Whether a laboratory reactor is used to study the fundamentals of a commercial process or for pure scientific interest, it is important to know what physical or chemical process is limiting or influencing the rate and selectivity. To clarify this, a definition is required of the regime where physical influences exist, and study the intrinsic kinetics at conditions where physical processes do not affect the rate. Reactors are illustrated whose design was influenced by the above considerations. These reactors produce results which are independent of the reactors in which they were measured, and which can be scaled up with up-to-date reaction engineering techniques.

  5. Spiral-shaped disinfection reactors

    KAUST Repository

    Ghaffour, Noreddine

    2015-08-20

    This disclosure includes disinfection reactors and processes for the disinfection of water. Some disinfection reactors include a body that defines an inlet, an outlet, and a spiral flow path between the inlet and the outlet, in which the body is configured to receive water and a disinfectant at the inlet such that the water is exposed to the disinfectant as the water flows through the spiral flow path. Also disclosed are processes for disinfecting water in such disinfection reactors.

  6. Turning points in reactor design

    Energy Technology Data Exchange (ETDEWEB)

    Beckjord, E.S.

    1995-09-01

    This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems.

  7. Acceptability of reactors in space

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.

    1981-04-01

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it dies not appear that reactors add measurably to the risk associated with the Space Transportation System.

  8. Hydrogen Production in Fusion Reactors

    OpenAIRE

    Sudo, S.; Tomita, Y.; Yamaguchi, S.; Iiyoshi, A.; Momota, H; Motojima, O.; Okamoto, M.; Ohnishi, M.; Onozuka, M; Uenosono, C.

    1993-01-01

    As one of methods of innovative energy production in fusion reactors without having a conventional turbine-type generator, an efficient use of radiation produced in a fusion reactor with utilizing semiconductor and supplying clean fuel in a form of hydrogen gas are studied. Taking the candidates of reactors such as a toroidal system and an open system for application of the new concepts, the expected efficiency and a concept of plant system are investigated.

  9. Fast reactor programme in India

    Indian Academy of Sciences (India)

    P Chellapandi; P R Vasudeva Rao; Prabhat Kumar

    2015-09-01

    Role of fast breeder reactor (FBR) in the Indian context has been discussed with appropriate justification. The FBR programme since 1985 till 2030 is highlighted focussing on the current status and future direction of fast breeder test reactor (FBTR), prototype fast breeder reactor (PFBR) and FBR-1 and 2. Design and technological challenges of PFBR and design and safety targets with means to achieve the same are the major highlights of this paper.

  10. Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence.

    Science.gov (United States)

    Colihueque, Nelson; Gantz, Alberto; Rau, Jaime Ricardo; Parraguez, Margarita

    2015-01-01

    In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy.

  11. Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence

    Science.gov (United States)

    Colihueque, Nelson; Gantz, Alberto; Rau, Jaime Ricardo; Parraguez, Margarita

    2015-01-01

    Abstract In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy. PMID:26668551

  12. Low Variation in the Polymorphic Clock Gene Poly-Q Region Despite Population Genetic Structure across Barn Swallow (Hirundo rustica) Populations

    Science.gov (United States)

    Dor, Roi; Lovette, Irby J.; Safran, Rebecca J.; Billerman, Shawn M.; Huber, Gernot H.; Vortman, Yoni; Lotem, Arnon; McGowan, Andrew; Evans, Matthew R.; Cooper, Caren B.; Winkler, David W.

    2011-01-01

    Recent studies of several species have reported a latitudinal cline in the circadian clock gene, Clock, which influences rhythms in both physiology and behavior. Latitudinal variation in this gene may hence reflect local adaptation to seasonal variation. In some bird populations, there is also an among-individual association between Clock poly-Q genotype and clutch initiation date and incubation period. We examined Clock poly-Q allele variation in the Barn Swallow (Hirundo rustica), a species with a cosmopolitan geographic distribution and considerable variation in life-history traits that may be influenced by the circadian clock. We genotyped Barn Swallows from five populations (from three subspecies) and compared variation at the Clock locus to that at microsatellite loci and mitochondrial DNA (mtDNA). We found very low variation in the Clock poly-Q region, as >96% of individuals were homozygous, and the two other alleles at this locus were globally rare. Genetic differentiation based on the Clock poly-Q locus was not correlated with genetic differentiation based on either microsatellite loci or mtDNA sequences. Our results show that high diversity in Clock poly-Q is not general across avian species. The low Clock variation in the background of heterogeneity in microsatellite and mtDNA loci in Barn Swallows may be an outcome of stabilizing selection on the Clock locus. PMID:22216124

  13. Low variation in the polymorphic Clock gene poly-Q region despite population genetic structure across barn swallow (Hirundo rustica populations.

    Directory of Open Access Journals (Sweden)

    Roi Dor

    Full Text Available Recent studies of several species have reported a latitudinal cline in the circadian clock gene, Clock, which influences rhythms in both physiology and behavior. Latitudinal variation in this gene may hence reflect local adaptation to seasonal variation. In some bird populations, there is also an among-individual association between Clock poly-Q genotype and clutch initiation date and incubation period. We examined Clock poly-Q allele variation in the Barn Swallow (Hirundo rustica, a species with a cosmopolitan geographic distribution and considerable variation in life-history traits that may be influenced by the circadian clock. We genotyped Barn Swallows from five populations (from three subspecies and compared variation at the Clock locus to that at microsatellite loci and mitochondrial DNA (mtDNA. We found very low variation in the Clock poly-Q region, as >96% of individuals were homozygous, and the two other alleles at this locus were globally rare. Genetic differentiation based on the Clock poly-Q locus was not correlated with genetic differentiation based on either microsatellite loci or mtDNA sequences. Our results show that high diversity in Clock poly-Q is not general across avian species. The low Clock variation in the background of heterogeneity in microsatellite and mtDNA loci in Barn Swallows may be an outcome of stabilizing selection on the Clock locus.

  14. Early monaural occlusion alters the neural map of interaural level differences in the inferior colliculus of the barn owl.

    Science.gov (United States)

    Mogdans, J; Knudsen, E I

    1993-08-13

    Monaural occlusion during early life causes adaptive changes in the tuning of units in the owl's optic tectum to interaural level differences (ILD) that tend to align the auditory with the visual map of space. We investigated whether these changes could be due to experience-dependent plasticity occurring in the auditory pathway prior to the optic tectum. Units were recorded in the external nucleus of the inferior colliculus (ICx), which is a major source of auditory input to the optic tectum. The tuning of ICx units to ILD was measured in normal barn owls and in barn owls raised with one ear occluded. ILD tuning at each recording site was measured with dichotic noise bursts, presented at a constant average binaural level, 20 dB above threshold. The best ILD at each site was defined as the midpoint of the range of ILD values which elicited more than 50% of the maximum response. A physiological map of ILD was found in the ICx of normal owls: best ILDs changed systematically from right-ear-greater to left-ear-greater as the electrode progressed from dorsal to ventral. Best ILDs ranged from 13 dB right-ear-greater to 15 dB left-ear-greater and progressed at an average rate of 12 dB/mm. The representations of ILD were similar on both sides of the brain. In the ICx of owls raised with one ear occluded, the map of ILD was shifted in the adaptive direction: ILD tuning was shifted towards values favoring the non-occluded ear (the direction that would restore a normal space map). The average magnitude of the shift was on the order of 8-10 dB in each of 4 owls. In one owl, the mean shift in ILD tuning was almost identical on both sides of the brain. In another owl, the mean shift was much larger on the side ipsilateral to the occlusion than on the contralateral side. In both cases, the mean shifts measured in each ICx were comparable to the mean shifts measured in the optic tectum on the same sides of the brain. Thus, the adjustments in ILD tuning that have been observed in

  15. Neutrino Oscillation Studies with Reactors

    CERN Document Server

    Vogel, Petr; Zhang, Chao

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective, and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavors are quantum mechanical mixtures. Over the past several decades reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle $\\theta_{13}$. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  16. Accelerator based fusion reactor

    Science.gov (United States)

    Liu, Keh-Fei; Chao, Alexander Wu

    2017-08-01

    A feasibility study of fusion reactors based on accelerators is carried out. We consider a novel scheme where a beam from the accelerator hits the target plasma on the resonance of the fusion reaction and establish characteristic criteria for a workable reactor. We consider the reactions d+t\\to n+α,d+{{}3}{{H}\\text{e}}\\to p+α , and p+{{}11}B\\to 3α in this study. The critical temperature of the plasma is determined from overcoming the stopping power of the beam with the fusion energy gain. The needed plasma lifetime is determined from the width of the resonance, the beam velocity and the plasma density. We estimate the critical beam flux by balancing the energy of fusion production against the plasma thermo-energy and the loss due to stopping power for the case of an inert plasma. The product of critical flux and plasma lifetime is independent of plasma density and has a weak dependence on temperature. Even though the critical temperatures for these reactions are lower than those for the thermonuclear reactors, the critical flux is in the range of {{10}22}-{{10}24}~\\text{c}{{\\text{m}}-2}~{{\\text{s}}-1} for the plasma density {ρt}={{10}15}~\\text{c}{{\\text{m}}-3} in the case of an inert plasma. Several approaches to control the growth of the two-stream instability are discussed. We have also considered several scenarios for practical implementation which will require further studies. Finally, we consider the case where the injected beam at the resonance energy maintains the plasma temperature and prolongs its lifetime to reach a steady state. The equations for power balance and particle number conservation are given for this case.

  17. 天然气水暖集中供热密集烤房设备的研究%Study on the bulk curing barn with central water heating by natural gas

    Institute of Scientific and Technical Information of China (English)

    任杰; 孙福山; 刘治清; 徐世峰; 许建设; 沈始权

    2013-01-01

      针对我国烟叶烘烤设备对煤炭依赖度高、环境污染重、烘烤用工量大的问题,利用液化天然气(LNG)为气源,集成LNG 气化技术、水暖集中供热技术,设计建造了天然气水暖集中供热密集烤房,并进行了烘烤试验。结果表明:天然气水暖集中供热密集烤房升温准,控温稳,能够满足烤烟密集烘烤对温湿度的要求。虽然较燃煤密集烤房能耗成本有所增加,但改善了烤后烟叶的外观质量,提高了上等烟比例,减少了烘烤用工和大气污染物排放量。%In order to resolve the problems of the bulk curing barn which depended on coal, contaminated environment and needed much labor, the bulk curing barn with central water heating by natural gas (gas fired bulk curing barn) utilizing liquefied natural gas as gas source was designed and built using liquefied natural gas gasification technique and central water heating supply technique. Effects of the bulk curing barn with central water heating by natural gas were investigated. The results indicated that heating-up of the gas fired bulk curing barn was very quick and sensitive to meet the temperature and humidity requirements of tobacco flue-curing. The gas fired bulk curing barn improved the surface quality of cured tobacco leaves and increased the proportion of classy cured tobacco leaves. Employment and emission amount of atmospheric pollutant of the gas fired bulk curing barn were less than that of the coal fired bulk curing barn, but the final cost of the gas fired bulk curing barn was more than that of the coal fired bulk curing barn.

  18. Biparticle fluidized bed reactor

    Science.gov (United States)

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  19. FAST NEUTRONIC REACTOR

    Science.gov (United States)

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  20. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC (Nuclear Regulatory Commission) licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor.

  1. Fast Reactor Fuel Type and Reactor Safety Performance

    Energy Technology Data Exchange (ETDEWEB)

    R. Wigeland; J. Cahalan

    2009-09-01

    Fast Reactor Fuel Type and Reactor Safety Performance R. Wigeland , Idaho National Laboratory J. Cahalan, Argonne National Laboratory The sodium-cooled fast neutron reactor is currently being evaluated for the efficient transmutation of the highly-hazardous, long-lived, transuranic elements that are present in spent nuclear fuel. One of the fundamental choices that will be made is the selection of the fuel type for the fast reactor, whether oxide, metal, carbide, nitride, etc. It is likely that a decision on the fuel type will need to be made before many of the related technologies and facilities can be selected, from fuel fabrication to spent fuel reprocessing. A decision on fuel type should consider all impacts on the fast reactor system, including safety. Past work has demonstrated that the choice of fuel type may have a significant impact on the severity of consequences arising from accidents, especially for severe accidents of low probability. In this paper, the response of sodium-cooled fast reactors is discussed for both oxide and metal fuel types, highlighting the similarities and differences in reactor response and accident consequences. Any fast reactor facility must be designed to be able to successfully prevent, mitigate, or accommodate all consequences of potential events, including accidents. This is typically accomplished by using multiple barriers to the release of radiation, including the cladding on the fuel, the intact primary cooling system, and most visibly the reactor containment building. More recently, this has also included the use of ‘inherent safety’ concepts to reduce or eliminate the potential for serious damage in some cases. Past experience with oxide and metal fuel has demonstrated that both fuel types are suitable for use as fuel in a sodium-cooled fast reactor. However, safety analyses for these two fuel types have also shown that there can be substantial differences in accident consequences due to the neutronic and

  2. Reactor Physics Analysis Models for a CANDU Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok

    2007-10-15

    Canada deuterium uranium (CANDU) reactor physics analysis is typically performed in three steps. At first, macroscopic cross-sections of the reference lattice is produced by modeling the reference fuel channel. Secondly macroscopic cross-sections of reactivity devices in the reactor are generated. The macroscopic cross-sections of a reactivity device are calculated as incremental cross-sections by subtracting macroscopic cross-sections of a three-dimensional lattice without reactivity device from those of a three-dimensional lattice with a reactivity device. Using the macroscopic cross-sections of the reference lattice and incremental cross-sections of the reactivity devices, reactor physics calculations are performed. This report summarizes input data of typical CANDU reactor physics codes, which can be utilized for the future CANDU reactor physics analysis.

  3. Reactor Physics Analysis Models for a CANDU Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok

    2007-10-15

    Canada deuterium uranium (CANDU) reactor physics analysis is typically performed in three steps. At first, macroscopic cross-sections of the reference lattice is produced by modeling the reference fuel channel. Secondly macroscopic cross-sections of reactivity devices in the reactor are generated. The macroscopic cross-sections of a reactivity device are calculated as incremental cross-sections by subtracting macroscopic cross-sections of a three-dimensional lattice without reactivity device from those of a three-dimensional lattice with a reactivity device. Using the macroscopic cross-sections of the reference lattice and incremental cross-sections of the reactivity devices, reactor physics calculations are performed. This report summarizes input data of typical CANDU reactor physics codes, which can be utilized for the future CANDU reactor physics analysis.

  4. The Study Result of the Solar Energy Application on Bulk Curing Barn%密集烤房的太阳能改造与应用研究

    Institute of Scientific and Technical Information of China (English)

    汪炳华; 徐天养; 肖华; 向成高; 何兵; 江红甲; 党云波; 李润涛

    2011-01-01

    为在烤烟烘烤期间利用太阳能替代部分燃煤,以达到节能减排的目的,对现有的密集烤房进行太阳能改造,在屋顶加装太阳能加热室,吸收太阳能并加热太阳能加热室内空气,高温空气通过内循环管道与烤房的加热室、装烟室连通,提供辅助热源。太阳能循环风机由温差控制器控制。对改造的太阳能密集烤房进行烘烤效应研究,结果表明密集型烤房的太阳能改造简单易行,经济实用,节能效果明显;太阳能提供的热量可满足烟叶烘烤前期的需要,每千克干烟耗能比改造前降低20%~24%,烘烤烟叶质量与普通密集烤房所烤烟叶质量相当,社会效益与经济效益明显,在光照好的烟区具有一定的推广价值。%In order to achieve energy conservation and emission reduction,a combination of energy from solar and coal has been built up based on a bulk curing barn by installing a solar heat system on the top of a bulk curing barn roof which are comprised of a heat room with valve controlled by a fan,lighting and heating transformation sheet and automatic temperature monitor.This study was focused on how much effect of the solar heating system could be as a supplemental energy to curing process,It has been turned out that not only a significant energy reduction has been achieved,but this modification bulk curing barn were easily constructed and economical,the solar energy could supply all heating from the early stage of tobacco curing process.The modified solar curing barn could save 20%-24%coal consumption per kg drying leaf as the one from a bulk curing barn at achieving the equivalent leaf quality.It has shown an encouraging prospective of benefit for economy and society especially on emission reduction and worthwhile for those area with abundant solar resource to extend this technology.

  5. Importance of Farmland in Urbanized Areas as a Landscape Component for Barn Swallows ( Hirundo rustica) Nesting on Concrete Buildings

    Science.gov (United States)

    Osawa, Takeshi

    2015-05-01

    Urbanization is one of the key factors in the population declines of many species. Conversely, some species may favor urbanized areas. The barn swallow Hirundo rustica is well known to breed in urban areas of Japan, and uses both urban and farmland areas as habitat during the breeding season. Specifically, this species often nests on concrete buildings and feeds in surrounding farmland. Therefore, it was hypothesized that H. rustica is not strongly influenced by heavy urbanization and benefits from farmland areas, even if they are not near its nests. In this study, I evaluated the landscape components around H. rustica nests situated on concrete buildings, focusing on both urbanized and farmland areas. In particular, I explored the occurrence of H. rustica nests at train stations in the Kinki region of Japan. Assisted by 124 citizen scientists, I analyzed the landscape components around the train stations at multiple spatial scales. Results showed that the occurrence of H. rustica nests was negatively influenced by both urbanized land area and road density, whereas nest occurrence was positively influenced by farmland area and river density. These results suggest that H. rustica does not prefer urbanized areas overall, but can rather utilize urbanized areas primarily as nesting spots. Therefore, H. rustica cannot breed in heavily urbanized areas without feeding sites such as farmland or riparian areas.

  6. Expression of Multiple Sexual Signals by Fathers and Sons in the East-Mediterranean Barn Swallow: Are Advertising Strategies Heritable?

    Science.gov (United States)

    Vortman, Yoni; Safran, Rebecca J.; Reiner Brodetzki, Tali; Dor, Roi; Lotem, Arnon

    2015-01-01

    The level of expression of sexually selected traits is generally determined by genes, environment and their interaction. In species that use multiple sexual signals which may be costly to produce, investing in the expression of one sexual signal may limit the expression of the other, favoring the evolution of a strategy for resource allocation among signals. As a result, even when the expression of sexual signals is condition dependent, the relative level of expression of each signal may be heritable. We tested this hypothesis in the East-Mediterranean barn swallow (Hirundo rustica transitiva), in which males have been shown to express two uncorrelated sexual signals: red-brown ventral coloration, and long tail streamers. We show that variation in both signals may partially be explained by age, as well as by paternal origin (genetic father-son regressions), but that the strongest similarity between fathers and sons is the relative allocation towards one trait or the other (relative expression index), rather than the expression of the traits themselves. These results suggest that the expression of one signal is not independent of the other, and that genetic strategies for resource allocation among sexual signals may be selected for during the evolution of multiple sexual signals. PMID:25679206

  7. Expression of multiple sexual signals by fathers and sons in the East-Mediterranean barn swallow: are advertising strategies heritable?

    Directory of Open Access Journals (Sweden)

    Yoni Vortman

    Full Text Available The level of expression of sexually selected traits is generally determined by genes, environment and their interaction. In species that use multiple sexual signals which may be costly to produce, investing in the expression of one sexual signal may limit the expression of the other, favoring the evolution of a strategy for resource allocation among signals. As a result, even when the expression of sexual signals is condition dependent, the relative level of expression of each signal may be heritable. We tested this hypothesis in the East-Mediterranean barn swallow (Hirundo rustica transitiva, in which males have been shown to express two uncorrelated sexual signals: red-brown ventral coloration, and long tail streamers. We show that variation in both signals may partially be explained by age, as well as by paternal origin (genetic father-son regressions, but that the strongest similarity between fathers and sons is the relative allocation towards one trait or the other (relative expression index, rather than the expression of the traits themselves. These results suggest that the expression of one signal is not independent of the other, and that genetic strategies for resource allocation among sexual signals may be selected for during the evolution of multiple sexual signals.

  8. Migration phenology and breeding success are predicted by methylation of a photoperiodic gene in the barn swallow

    Science.gov (United States)

    Saino, Nicola; Ambrosini, Roberto; Albetti, Benedetta; Caprioli, Manuela; De Giorgio, Barbara; Gatti, Emanuele; Liechti, Felix; Parolini, Marco; Romano, Andrea; Romano, Maria; Scandolara, Chiara; Gianfranceschi, Luca; Bollati, Valentina; Rubolini, Diego

    2017-01-01

    Individuals often considerably differ in the timing of their life-cycle events, with major consequences for individual fitness, and, ultimately, for population dynamics. Phenological variation can arise from genetic effects but also from epigenetic modifications in DNA expression and translation. Here, we tested if CpG methylation at the poly-Q and 5′-UTR loci of the photoperiodic Clock gene predicted migration and breeding phenology of long-distance migratory barn swallows (Hirundo rustica) that were tracked year-round using light-level geolocators. Increasing methylation at Clock poly-Q was associated with earlier spring departure from the African wintering area, arrival date at the European breeding site, and breeding date. Higher methylation levels also predicted increased breeding success. Thus, we showed for the first time in any species that CpG methylation at a candidate gene may affect phenology and breeding performance. Methylation at Clock may be a candidate mechanism mediating phenological responses of migratory birds to ongoing climate change. PMID:28361883

  9. A critical period for the recovery of sound localization accuracy following monaural occlusion in the barn owl.

    Science.gov (United States)

    Knudsen, E I; Knudsen, P F; Esterly, S D

    1984-04-01

    We studied the ability of barn owls to recover accurate sound localization after being raised with one ear occluded. Most of the owls had ear plugs inserted before they reached adult size, and therefore they never experienced normal adult localization cues until their ear plugs were removed. Upon removal of their ear plugs, these owls exhibited large systematic sound localization errors. The rate at which they recovered accurate localization decreased with the age of the bird at the time of plug removal, and recovery essentially ceased when owls reached 38 to 42 weeks of age. We interpret this age as the end of a critical period for the consolidation of associations between auditory cues and locations in space. Owls that had experienced adult localization cues for a short period of time before ear plugging recovered normal accuracy rapidly, even if they remained plugged well past the end of the critical period. This suggests that a brief exposure to normal adult cues early in the critical period is sufficient to enable the recovery of localization accuracy much later in life.

  10. Cassia spectabilis (DC Irwin et Barn: A Promising Traditional Herb in Health Improvement

    Directory of Open Access Journals (Sweden)

    Subramanian Deivanai

    2012-08-01

    Full Text Available The genus Cassia, comprising about 600 species widely distributed worldwide is well known for its diverse biological and pharmacological properties. Cassia spectabilis (sin Senna spectabilis (DC Irwin et Barn (Fabaceae is widely grown as an ornamental plant in tropical and subtropical areas. C. spectabilis has been commonly used in traditional medicine for many years. Information in the biomedical literature has indicated the presence of a variety of medicinally-important chemical constituents in C. spectabilis. Pharmacological studies by various groups of investigators have shown that C. spectabilis possesses significant biological activity, such as antibacterial, antibiofilm, antifungal and antioxidant properties. Beside this, toxicity studies of this plant have revealed no toxic effect on mice. In view of the immense medicinal importance of C. spectabilis, this review aimed at compiling all currently available information on C. spectabilis’s botany, phytochemistry, pharmacology, and mechanism of actions, toxicology and its ethnomedicinal uses.

  11. Description of 44 biosecurity errors while entering and exiting poultry barns based on video surveillance in Quebec, Canada.

    Science.gov (United States)

    Racicot, Manon; Venne, Daniel; Durivage, André; Vaillancourt, Jean-Pierre

    2011-07-01

    The effectiveness of biosecurity measures depends largely on the consistency of their applications by all those involved in poultry production. Unfortunately, poor biosecurity compliance has been reported repeatedly in poultry, as well in all other major animal productions. As part of a larger study, we conducted an investigation on eight poultry farms in Quebec, Canada, to evaluate compliance of existing biosecurity measures using hidden cameras. The objectives were to evaluate and describe the application of biosecurity measures when entering and exiting poultry barns. A total of 44 different mistakes were observed from 883 visits done by 102 different individuals. On average, four errors were recorded per visit. The maximum number of errors made by one individual during one visit was 14. People observed over several visits made on average six different errors. Twenty-seven out of the 44 errors (61.4%) were related to area delimitation (clean versus contaminated), six to boots (13.6%), five to hand washing (11.4%), three to coveralls (6.8%) and three to logbooks (6.8%). The nature and frequency of errors suggest a lack of understanding of biosecurity principles. There is thus a need to improve biosecurity training by making educational material available to all poultry personnel demonstrating why and how to apply biosecurity measures.

  12. Migration phenology and breeding success are predicted by methylation of a photoperiodic gene in the barn swallow.

    Science.gov (United States)

    Saino, Nicola; Ambrosini, Roberto; Albetti, Benedetta; Caprioli, Manuela; De Giorgio, Barbara; Gatti, Emanuele; Liechti, Felix; Parolini, Marco; Romano, Andrea; Romano, Maria; Scandolara, Chiara; Gianfranceschi, Luca; Bollati, Valentina; Rubolini, Diego

    2017-03-31

    Individuals often considerably differ in the timing of their life-cycle events, with major consequences for individual fitness, and, ultimately, for population dynamics. Phenological variation can arise from genetic effects but also from epigenetic modifications in DNA expression and translation. Here, we tested if CpG methylation at the poly-Q and 5'-UTR loci of the photoperiodic Clock gene predicted migration and breeding phenology of long-distance migratory barn swallows (Hirundo rustica) that were tracked year-round using light-level geolocators. Increasing methylation at Clock poly-Q was associated with earlier spring departure from the African wintering area, arrival date at the European breeding site, and breeding date. Higher methylation levels also predicted increased breeding success. Thus, we showed for the first time in any species that CpG methylation at a candidate gene may affect phenology and breeding performance. Methylation at Clock may be a candidate mechanism mediating phenological responses of migratory birds to ongoing climate change.

  13. Effect of voluntary physical exercise and post-training epinephrine on acquisition of a spatial task in the barnes maze.

    Science.gov (United States)

    Jacotte-Simancas, Alejandra; Costa-Miserachs, David; Torras-Garcia, Meritxell; Coll-Andreu, Margalida; Portell-Cortés, Isabel

    2013-06-15

    A number of experiments have shown that physical exercise improves acquisition and retention for a variety of learning tasks in rodents. Most of these works have been conducted with tasks associated with a considerable level of stress, physical effort and/or food deprivation that might interact with exercise, thus hindering the interpretation of the results. On the other hand, it is well established that post-training epinephrine is able to facilitate memory consolidation, but only a few works have studied its effect on the process of acquisition. The present work was aimed at studying whether 17 days of voluntary physical exercise (running wheels) and/or post-training epinephrine (0.01 or 0.05 mg/kg) could improve the acquisition of a spatial task in the Barnes maze, and whether the combination of the two treatments have additive effects. Our results showed that exercise improved acquisition, and 0.01 mg/kg of epinephrine tended to enhance it, by reducing the distance needed to find the escape hole. The combination of both treatments failed to further improve the acquisition level. We concluded that both treatments exerted their effect on acquisition by enhancing the process of learning itself, and that exercise is able to improve acquisition even using tasks with a low level of stress and physical effort.

  14. Barnes-Evans relations for dwarfs with an application to the determination of distances to cataclysmic variables

    CERN Document Server

    Beuermann, K

    2006-01-01

    Barnes-Evans type relations provide an empirical relationship between the surface brightness of stars and their color. They are widely used for measuring the distances to stars of known radii, as the Roche-lobe filling secondaries in cataclysmic variables (CVs). The calibration of the surface brightness of field dwarfs of near-solar metalicity with spectral types A0 to L8 covers all secondary spectral types detectable in CVs and related objects and will aid in the measurement of their distances. The calibrations are based on the radii of field dwarfs measured by the Infrared Flux Method and by interferometry. Published photometry is used and homogenized to the Cousins Rc and Ic and the CIT JHK photometric systems. The narrow band surface brightness at 7500A is based on our own and published spectrophotometry. Care is taken to select the dwarfs for near-solar metalicity, appropriate to CVs, and to avoid errors caused by unrecognized binarity. Relations are provided for the surface brightness in V, Rc, Ic, J, H...

  15. Inferring the Skeletal Muscle Developmental Changes of Grazing and Barn-Fed Goats from Gene Expression Data.

    Science.gov (United States)

    Huang, Jinyu; Jiao, Jinzhen; Tan, Zhi-Liang; He, Zhixiong; Beauchemin, Karen A; Forster, Robert; Han, Xue-Feng; Tang, Shao-Xun; Kang, Jinghe; Zhou, Chuanshe

    2016-09-14

    Thirty-six Xiangdong black goats were used to investigate age-related mRNA and protein expression levels of some genes related to skeletal muscle structural proteins, MRFs and MEF2 family, and skeletal muscle fiber type and composition during skeletal muscle growth under grazing (G) and barn-fed (BF) feeding systems. Goats were slaughtered at six time points selected to reflect developmental changes of skeletal muscle during nonrumination (days 0, 7, and 14), transition (day 42), and rumination phases (days 56 and 70). It was observed that the number of type IIx in the longissimus dorsi was increased quickly while numbers of type IIa and IIb decreased slightly, indicating that these genes were coordinated during the rapid growth and development stages of skeletal muscle. No gene expression was affected (P > 0.05) by feeding system except Myf5 and Myf6. Protein expressions of MYOZ3 and MEF2C were affected (P nutrition or feeding regimen mainly influences the expression of skeletal muscle growth genes.

  16. Hvilket barn? Om barn, barndom og barnehage

    Directory of Open Access Journals (Sweden)

    Agnes Andenæs

    2012-01-01

    Full Text Available Title: What kind of a child? On children’s everyday life, Early Childhood Education, and psychological developmentAbstract: Public discussions about day care more or less explicitly refer to models about children’s development. My argument is that the field of Early Childhood Education does need understandings offered by the discipline of developmental psychology, but that the hegemonic ones strongly restrict ways of talking about what is going on at the day care institutions, and what day care means to the participants, included parents and other caretakers. A more context sensitive and meaning making oriented version of developmental psychology is presented, and empirical examples are used to demonstrate how this way of understanding children widens up ways of talking about day care: as an arena for children’s participation, as a link in parents’ chain of care for their child, and as a meeting point for diversity. Keywords: Developmental psychology; Day care; Everyday life; Parenthood; Chain of care; Social participation

  17. Chemical-vapor-deposition reactor

    Science.gov (United States)

    Chern, S.

    1979-01-01

    Reactor utilizes multiple stacked trays compactly arranged in paths of horizontally channeled reactant gas streams. Design allows faster and more efficient deposits of film on substrates, and reduces gas and energy consumption. Lack of dead spots that trap reactive gases reduces reactor purge time.

  18. Thermochemical reactor systems and methods

    Energy Technology Data Exchange (ETDEWEB)

    Lipinski, Wojciech; Davidson, Jane Holloway; Chase, Thomas Richard

    2016-11-29

    Thermochemical reactor systems that may be used to produce a fuel, and methods of using the thermochemical reactor systems, utilizing a reactive cylindrical element, an optional energy transfer cylindrical element, an inlet gas management system, and an outlet gas management system.

  19. Test reactor risk assessment methodology

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, R.H.; Rawlins, J.K.; Stewart, M.E.

    1976-04-01

    A methodology has been developed for the identification of accident initiating events and the fault modeling of systems, including common mode identification, as these methods are applied in overall test reactor risk assessment. The methods are exemplified by a determination of risks to a loss of primary coolant flow in the Engineering Test Reactor.

  20. Studies on a membrane reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, K.; Govind, R.

    1988-10-01

    Simulation is used to evaluate the performance of a catalytic reactor with permeable wall (membrane reactor) in shifting the equilibrium of three reversible reactions (cyclohexane dehydrogenation, hydrogen iodide decomposition, and propylene disproportionation). It is found that the preferred choice of cocurrernt or countercurrent operation is dependent on the physical properties and operating conditions. Methods of enhancing conversion are suggested and temperature effects are discussed.

  1. Thermochemical reactor systems and methods

    Science.gov (United States)

    Lipinski, Wojciech; Davidson, Jane Holloway; Chase, Thomas Richard

    2016-11-29

    Thermochemical reactor systems that may be used to produce a fuel, and methods of using the thermochemical reactor systems, utilizing a reactive cylindrical element, an optional energy transfer cylindrical element, an inlet gas management system, and an outlet gas management system.

  2. Brookhaven leak reactor to close

    CERN Multimedia

    MacIlwain, C

    1999-01-01

    The DOE has announced that the High Flux Beam Reactor at Brookhaven is to close for good. Though the news was not unexpected researchers were angry the decision had been taken before the review to assess the impact of reopening the reactor had been concluded (1 page).

  3. Metallic fuels for advanced reactors

    Science.gov (United States)

    Carmack, W. J.; Porter, D. L.; Chang, Y. I.; Hayes, S. L.; Meyer, M. K.; Burkes, D. E.; Lee, C. B.; Mizuno, T.; Delage, F.; Somers, J.

    2009-07-01

    In the framework of the Generation IV Sodium Fast Reactor Program, the Advanced Fuel Project has conducted an evaluation of the available fuel systems supporting future sodium cooled fast reactors. This paper presents an evaluation of metallic alloy fuels. Early US fast reactor developers originally favored metal alloy fuel due to its high fissile density and compatibility with sodium. The goal of fast reactor fuel development programs is to develop and qualify a nuclear fuel system that performs all of the functions of a conventional fast spectrum nuclear fuel while destroying recycled actinides. This will provide a mechanism for closure of the nuclear fuel cycle. Metal fuels are candidates for this application, based on documented performance of metallic fast reactor fuels and the early results of tests currently being conducted in US and international transmutation fuel development programs.

  4. A model of reactor kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.S.; Thompson, B.R.

    1988-09-01

    The analytical model of nuclear reactor transients, incorporating both mechanical and nuclear effects, simulates reactor kinetics. Linear analysis shows the stability borderline for small power perturbations. In a stable system, initial power disturbances die out with time. With an unstable combination of nuclear and mechanical characteristics, initial disturbances persist and may increase with time. With large instability, oscillations of great magnitude occur. Stability requirements set limits on the power density at which particular reactors can operate. The limiting power density depends largely on the product of two terms: the fraction of delayed neutrons and the frictional damping of vibratory motion in reactor core components. As the fraction of delayed neutrons is essentially fixed, mechanical damping largely determines the maximum power density. A computer program, based on the analytical model, calculates and plots reactor power as a nonlinear function of time in response to assigned values of mechanical and nuclear characteristics.

  5. Engineering reactors for catalytic reactions

    Indian Academy of Sciences (India)

    Vivek V Ranade

    2014-03-01

    Catalytic reactions are ubiquitous in chemical and allied industries. A homogeneous or heterogeneous catalyst which provides an alternative route of reaction with lower activation energy and better control on selectivity can make substantial impact on process viability and economics. Extensive studies have been conducted to establish sound basis for design and engineering of reactors for practising such catalytic reactions and for realizing improvements in reactor performance. In this article, application of recent (and not so recent) developments in engineering reactors for catalytic reactions is discussed. Some examples where performance enhancement was realized by catalyst design, appropriate choice of reactor, better injection and dispersion strategies and recent advances in process intensification/ multifunctional reactors are discussed to illustrate the approach.

  6. Unsteady processes in catalytic reactors

    Energy Technology Data Exchange (ETDEWEB)

    Matros, Yu.Sh.

    1985-01-01

    In recent years a realization has occurred that reaction and reactor dynamics must be considered when designing and operating catalytic reactors. In this book, the author has focussed on both the processes occurring on individual porous-catalyst particles as well as the phenomena displayed by collections of these particles in fixed-bed reactors. The major topics discussed include the effects of unsteady-state heat and mass transfer, the influence of inhomogeneities and stagnant regions in fixed beds, and reactor operation during forced cycling of operating conditions. Despite the title of the book, attention is also paid to the determination of the number and stability of fixed-bed steady states, with the aim of describing the possibility of controlling reactors at unstable steady states. However, this development is somewhat dated, given the recent literature on multiplicity phenomena and process control.

  7. Antineutrino Monitoring of Thorium Reactors

    CERN Document Server

    Akindele, Oluwatomi A; Norman, Eric B

    2015-01-01

    Various groups have demonstrated that antineutrino monitoring can be successful in assessing the plutonium content in water-cooled nuclear reactors for nonproliferation applications. New reactor designs and concepts incorporate nontraditional fuels types and chemistry. Understanding how these properties affect the antineutrino emission from a reactor can extend the applicability of antineutrino monitoring.Thorium molten salt reactors (MSR) breed U-233, that if diverted constitute an IAEA direct use material. The antineutrino spectrum from the fission of U-233 has been determined, the feasibility of detecting the diversion of a significant quantity, 8 kg of U-233, within the IAEA timeliness goal of 30 days has been evaluated. The antineutrino emission from a thorium reactor operating under normal conditions is compared to a diversion scenario at a 25 meter standoff by evaluating the daily antineutrino count rate and the energy spectrum of the detected antineutrinos. It was found that the diversion of a signifi...

  8. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards.

  9. University Reactor Conversion Lessons Learned Workshop for Purdue University Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Eric C. Woolstenhulme; Dana M. Hewit

    2008-09-01

    The Department of Energy’s Idaho National Laboratory, under its programmatic responsibility for managing the University Research Reactor Conversions, has completed the conversion of the reactor at Purdue University Reactor. With this work completed and in anticipation of other impending conversion projects, the INL convened and engaged the project participants in a structured discussion to capture the lessons learned. The lessons learned process has allowed us to capture gaps, opportunities, and good practices, drawing from the project team’s experiences. These lessons will be used to raise the standard of excellence, effectiveness, and efficiency in all future conversion projects.

  10. Interaktionens betydelse för barns lärande - en studie av barns möte med slöjd i förskolan

    Directory of Open Access Journals (Sweden)

    Eva Ahlskog-Björkman

    2014-06-01

    Full Text Available Syftet med den här artikeln är att diskutera på vilket sätt interaktion och socialt samspel har betydelse för hur barn i förskolan kan engageras i en lärandeprocess. Den empiriska studien utgörs av en  videofilmad episod över en vävaktivitet i förskola. Genom att använda videografisk observation kan mänsklig aktivitet beskrivas och av den anledningen används  videografi som metodologisk ansats. I studien analyseras på vilket sätt interaktionen mellan de som är närvarande, oberoende av barnens ålder, kan bidra till att stimulera den lärande aktiviteten. Barnens slöjdaktivitet beaktas ur ett sociokulturellt lärandeperspektiv. Ett centralt tema inom detta perspektiv är kommunikation där språket och redskapen står för de medierande faktorerna. Barnens kontakt med redskapen och deras upplevelser och erfarande av slöjdaktiviteten diskuteras i relation till den närmaste utvecklingszonen. Ytterligare beaktas den videofilmade sekvensen ur ett socialt perspektiv där barnpedagogens agerande gentemot barnen lyfts fram och diskuteras. Analys och tolkning av datamaterialet strävar efter att synliggöra mänsklig interaktion och dess betydelse för att motivera och engagera barnen i deras slöjdaktivitet.  

  11. Neutronic Reactor Shield

    Science.gov (United States)

    Fermi, Enrico; Zinn, Walter H.

    The argument of the present Patent is a radiation shield suitable for protection of personnel from both gamma rays and neutrons. Such a shield from dangerous radiations is achieved to the best by the combined action of a neutron slowing material (a moderator) and a neutron absorbing material. Hydrogen is particularly effective for this shield since it is a good absorber of slow neutrons and a good moderator of fast neutrons. The neutrons slowed down by hydrogen may, then, be absorbed by other materials such as boron, cadmium, gadolinium, samarium or steel. Steel is particularly convenient for the purpose, given its effectiveness in absorbing also the gamma rays from the reactor (both primary gamma rays and secondary ones produced by the moderation of neutrons). In particular, in the present Patent a shield is described, made of alternate layers of steel and Masonite (an hydrolized ligno-cellulose material). The object of the present Patent is not discussed in any other published paper.

  12. Neutrino Experiments at Reactors

    Science.gov (United States)

    Reines, F.; Gurr, H. S.; Jenkins, T. L.; Munsee, J. H.

    1968-09-09

    A description is given of the electron-antineutrino program using a large fission reactor. A search has been made for a neutral weak interaction via the reaction (electron antineutrino + d .> p + n + electron antineutrino), the reaction (electron antineutrino + d .> n + n + e{sup +}) has now been detected, and an effort is underway to observe the elastic scattering reaction (electron antineutrino + e{sup -} .> electron antineutrino + e{sup -}) as well as to measure more precisely the reaction (electron antineutrino + p .> n + e{sup+}). The upper limit on the elastic scattering reaction which we have obtained with our large composite NaI, plastic, liquid scintillation detector is now about 50 times the predicted value.

  13. Gereformeerde kerk te Wageningen 1970 [The Reformed church in Wageningen 1970

    NARCIS (Netherlands)

    Wemmenhove, B.

    1970-01-01

    Frequency of church attendance / membership of club, elders and deacons, church committee / opinion on cooperation with other religious denominations in religious services / discussions during service / holy communion / dropping afternoon service / political point of view in sermon / pastoral visits

  14. Gereformeerde kerk te Wageningen 1970 [The Reformed church in Wageningen 1970

    NARCIS (Netherlands)

    Wemmenhove, B.

    2007-01-01

    Frequency of church attendance / membership of club, elders and deacons, church committee / opinion on cooperation with other religious denominations in religious services / discussions during service / holy communion / dropping afternoon service / political point of view in sermon / pastoral visits

  15. Reactor service life extension program

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-12-31

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  16. Reactor service life extension program

    Energy Technology Data Exchange (ETDEWEB)

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-01-01

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  17. Assessment of torsatrons as reactors

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, J.F. (Oak Ridge National Lab., TN (United States)); Painter, S.L. (Australian National Univ., Canberra, ACT (Australia))

    1992-12-01

    Stellarators have significant operational advantages over tokamaks as ignited steady-state reactors because stellarators have no dangerous disruptions and no need for continuous current drive or power recirculated to the plasma, both easing the first wall, blanket, and shield design; less severe constraints on the plasma parameters and profiles; and better access for maintenance. This study shows that a reactor based on the torsatron configuration (a stellarator variant) could also have up to double the mass utilization efficiency (MUE) and a significantly lower cost of electricity (COE) than a conventional tokamak reactor (ARIES-I) for a range of assumptions. Torsatron reactors can have much smaller coil systems than tokamak reactors because the coils are closer to the plasma and they have a smaller cross section (higher average current density because of the lower magnetic field). The reactor optimization approach and the costing and component models are those used in the current stage of the ARIES-I tokamak reactor study. Typical reactor parameters for a 1-GW(e) Compact Torsatron reactor example are major radius R[sub 0] = 6.6-8.8 m, on-axis magnetic field B[sup 0] = 4.8-7.5 T, B[sub max] (on coils) = 16 T, MUE 140-210 kW(e)/tonne, and COE (in constant 1990 dollars) = 67-79 mill/kW(e)h. The results are relatively sensitive to assumptions on the level of confinement improvement and the blanket thickness under the inboard half of the helical windings but relatively insensitive to other assumptions.

  18. Investimento em unidades de cura para tabaco tipo Virginia = Investments in tobacco curing barn for Virginia variety

    Directory of Open Access Journals (Sweden)

    Ricardo Luiz Boettcher

    2017-01-01

    Full Text Available A fumicultura na região Sul do Brasil está fundamentada no sistema integrado de produção. Ao longo do processo produtivo, há a necessidade de utilização de unidades de cura e secagem (estufas, sendo um investimento oneroso ao produtor. Dois sistemas de estufas predominam e de funcionamento distintos, os de estufas convencionais (convecção natural do ar e com circulação forçada do ar. O sistema de circulação forçada é o modelo preferido pelos produtores que optam por fazer novos investimentos. A decisão em investir demanda criteriosa análise da viabilidade econômica por parte do produtor, para minimizar risco de endividamentos. O objetivo do trabalho foi determinar a viabilidade financeira de unidades de cura para tabaco nas modalidades de financiamento com juros de crédito rural e juros de crédito rural subvencionados. As ferramentas financeiras utilizadas foram Valor Presente Líquido [VPL], Taxa Interna de Retorno [TIR], payback simples e análise de sensibilidade do investimento em relação à variável produtividade (kg ha-1. Utilizando taxa mínima de atratividade [TMA] 7,16%, o investimento não apresenta viabilidade econômica nas duas modalidades de juros, considerando a produtividade média histórica, o modelo de estufa selecionado e prazo de amortização. A análise de sensibilidade confirmou a produtividade (kg ha-1 como fator determinante da viabilidade do projeto. O incremento de >10% na produtividade média, reverte o quadro e o projeto passa a ser economicamente viável nas duas modalidades de juros de amortização do investimento. = The tobacco production in the south of Brazil is based on the integrated production system. Along with this system, there is a need to use curing barn to cure and dry, bringing an expensive investment for farmers. Two distinct curing systems are predominant which are the conventional (convection and air force circulation system. The air force system is the preferred model by

  19. Safety of VVER-440 reactors

    CERN Document Server

    Slugen, Vladimir

    2011-01-01

    Safety of VVER-440 Reactors endeavours to promote an increase in the safety of VVER-440 nuclear reactors via the improvement of fission products limitation systems and the implementation of special non-destructive spectroscopic methods for materials testing. All theoretical and experimental studies performed the by author over the last 25 years have been undertaken with the aim of improving VVER-440 defence in depth, which is one of the most important principle for ensuring safety in nuclear power plants. Safety of VVER-440 Reactors is focused on the barrier system through which the safety pri

  20. Random processes in nuclear reactors

    CERN Document Server

    Williams, M M R

    1974-01-01

    Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

  1. Reactor neutrons in nuclear astrophysics

    Science.gov (United States)

    Reifarth, René; Glorius, Jan; Göbel, Kathrin; Heftrich, Tanja; Jentschel, Michael; Jurado, Beatriz; Käppeler, Franz; Köster, Ulli; Langer, Christoph; Litvinov, Yuri A.; Weigand, Mario

    2017-09-01

    The huge neutron fluxes offer the possibility to use research reactors to produce isotopes of interest, which can be investigated afterwards. An example is the half-lives of long-lived isotopes like 129I. A direct usage of reactor neutrons in the astrophysical energy regime is only possible, if the corresponding ions are not at rest in the laboratory frame. The combination of an ion storage ring with a reactor and a neutron guide could open the path to direct measurements of neutron-induced cross sections on short-lived radioactive isotopes in the astrophysically interesting energy regime.

  2. Concept for LEU Burst Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Steven Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimpland, Robert Herbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-07

    Design and performance of a proposed LEU burst reactor are sketched. Salient conclusions reached are the following: size would be ~1,500 kg or greater, depending on the size of the central cavity; internal stresses during burst require split rings for relief; the reactor would likely require multiple control and safety rods for fine control; the energy spectrum would be comparable to that of HEU machines; and burst yields and steady-state power levels will be significantly greater in an LEU reactor.

  3. Nuclear reactor downcomer flow deflector

    Energy Technology Data Exchange (ETDEWEB)

    Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

    2011-02-15

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  4. Fuel Fabrication and Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-02

    The uranium from the enrichment plant is still in the form of UF6. UF6 is not suitable for use in a reactor due to its highly corrosive chemistry as well as its phase diagram. UF6 is converted into UO2 fuel pellets, which are in turn placed in fuel rods and assemblies. Reactor designs are variable in moderators, coolants, fuel, performance etc.The dream of energy ‘too-cheap to meter’ is no more, and now the nuclear power industry is pushing ahead with advanced reactor designs.

  5. Longevity and lifetime reproductive success of barn swallow offspring are predicted by their hatching date and phenotypic quality.

    Science.gov (United States)

    Saino, Nicola; Romano, Maria; Ambrosini, Roberto; Rubolini, Diego; Boncoraglio, Giuseppe; Caprioli, Manuela; Romano, Andrea

    2012-09-01

    1. Longevity is a major determinant of individual differences in Darwinian fitness. Several studies have analyzed the stochastic, time-dependent causes of variation in longevity, but little information exists from free-ranging animal populations on the effects that environmental conditions and phenotype early in ontogeny have on duration of life. 2. In this long-term (1993-2011) study of a migratory, colonial, passerine bird, the barn swallow (Hirundo rustica), we analyzed longevity and, in a subsample of individuals, lifetime reproductive success (LRS) of the offspring that reached sexual maturity in relation to hatching date, which can affect the rearing environment through a seasonal deterioration in ecological conditions. Moreover, we analyzed the consequences of variation in body size and, for the first time in any species, of a major component of immunity on longevity, both by looking at absolute phenotypic values and at deviations from the brood mean. 3. Accelerated failure time models showed that individuals of both sexes that hatched early in any breeding season enjoyed larger longevity and larger LRS, indicating directional selection for early breeding. Both male and female offspring with large T cell-mediated immune response relative to their siblings and female nestlings that dominated the brood size/age hierarchy had larger longevity than their siblings of inferior phenotypic quality/age. Conversely, absolute phenotypic values did not predict longevity. 4. Frailty modelling disclosed marked spatial heterogeneity in longevity among colonies of origin, again stressing the impact of rearing conditions on longevity. 5. This study therefore reinforces the notion that perinatal environment and maternal decisions over timing and site of breeding, and position in the brood hierarchy can have marked effects on progeny life history that extend well into adulthood. In addition, it provides the first evidence from any bird population in the wild that immune

  6. Early-Life Telomere Dynamics Differ between the Sexes and Predict Growth in the Barn Swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Marco Parolini

    Full Text Available Telomeres are conserved DNA-protein structures at the termini of eukaryotic chromosomes which contribute to maintenance of genome integrity, and their shortening leads to cell senescence, with negative consequences for organismal functions. Because telomere erosion is influenced by extrinsic and endogenous factors, telomere dynamics may provide a mechanistic basis for evolutionary and physiological trade-offs. Yet, knowledge of fundamental aspects of telomere biology under natural selection regimes, including sex- and context-dependent variation in early-life, and the covariation between telomere dynamics and growth, is scant. In this study of barn swallows (Hirundo rustica we investigated the sex-dependent telomere erosion during nestling period, and the covariation between relative telomere length and body and plumage growth. Finally, we tested whether any covariation between growth traits and relative telomere length depends on the social environment, as influenced by sibling sex ratio. Relative telomere length declined on average over the period of nestling maximal growth rate (between 7 and 16 days of age and differently covaried with initial relative telomere length in either sex. The frequency distribution of changes in relative telomere length was bimodal, with most nestlings decreasing and some increasing relative telomere length, but none of the offspring traits predicted the a posteriori identified group to which individual nestlings belonged. Tail and wing length increased with relative telomere length, but more steeply in males than females, and this relationship held both at the within- and among-broods levels. Moreover, the increase in plumage phenotypic values was steeper when the sex ratio of an individual's siblings was female-biased. Our study provides evidence for telomere shortening during early life according to subtly different dynamics in either sex. Furthermore, it shows that the positive covariation between growth and

  7. Mammal prey of the Barn Owl (Tyto alba in Parque Luro Reserve, La Pampa, Argentina

    Directory of Open Access Journals (Sweden)

    Sergio Tiranti

    1994-05-01

    Full Text Available Abstract The diet of the barn owl was studied through the analysis of pellets obtained in various sites within the Parque Luro reserve, located in an area of xerophyte Caldén forests. The study of 1241 prey items revealed a high dominance of the cricetid rodents Calomys sp., Akodon molinae and Eligmodontia typus, followed by other 8 species of rodents, one species of marsupial and undetermined birds and anuran amphibians. For comparing the diets from a relatively undisturbed forested area (Parque Luro and a deforested site, two subcollections of pellets were analyzed. Differences in FNB values and in the prevalence and composition of prey assemblages were observed between these areas. Riassunto Mammiferi predati dal Barbagianni (Tyto alba nella Riserva Parque Luro, La Pampa, Argentina - La dieta del Barbagianni (Tyto alba è stata studiata attraverso l'analisi delle borre ottenute in varie località all'interno della riserva Parque Luro, situata in un'area con boschi xerofili a Prosopis caldenia. Lo studio di 1241 campioni ha rivelato un'elevata prevalenza di roditori cricetidi Calomys sp., Akodon molinae and Eligmodontia typus, seguiti da altre 8 specie di roditori, una specie di marsupiali e uccelli e anfibi anuri indeterminati. Per il confronto delle diete sono state analizzate due sub-raccolte di borre di rapaci provenienti da un'area boscata relativamente indisturbata e da un sito disboscato. In queste aree sono state osservate differenze nei valori della FNB e nella prevalenza e composizione delle prede.

  8. Measured and modelled tritium concentrations in freshwater Barnes mussels (Elliptio complanata) exposed to an abrupt increase in ambient tritium levels.

    Science.gov (United States)

    Yankovich, T L; Kim, S B; Baumgärtner, F; Galeriu, D; Melintescu, A; Miyamoto, K; Saito, M; Siclet, F; Davis, P

    2011-01-01

    To improve understanding of environmental tritium behaviour, the International Atomic Energy Agency (IAEA) included a Tritium and C-14 Working Group (WG) in its EMRAS (Environmental Modelling for Radiation Safety) program. One scenario considered by the WG involved the prediction of time-dependent tritium concentrations in freshwater mussels that were subjected to an abrupt increase in ambient tritium levels. The experimental data used in the scenario were obtained from a study in which freshwater Barnes mussels (Elliptio complanata) were transplanted from an area with background tritium concentrations to a small Canadian Shield lake that contains elevated tritium. The mussels were then sampled over 88 days, and concentrations of free-water tritium (HTO) and organically-bound tritium (OBT) were measured in the soft tissues to follow the build-up of tritium in the mussels over time. The HTO concentration in the mussels reached steady state with the concentration in lake water within one or two hours. Most models predicted a longer time (up to a few days) to equilibrium. All models under-predicted the OBT concentration in the mussels one hour after transplantation, but over-predicted the rate of OBT formation over the next 24h. Subsequent dynamics were not well modelled, although all participants predicted OBT concentrations that were within a factor of three of the observation at the end of the study period. The concentration at the final time point was over-predicted by all but one of the models. The relatively low observed concentration at this time was likely due to the loss of OBT by mussels during reproduction. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Influence of contralateral acoustic stimulation on distortion-product and spontaneous otoacoustic emissions in the barn owl.

    Science.gov (United States)

    Manley, G A; Taschenberger, G; Oeckinghaus, H

    1999-12-01

    The avian auditory papilla provides an interesting object on which to study efferent influences, because whereas a significant population of hair cells in birds is not afferently innervated, all hair cells are efferently innervated (Fischer, 1992, 1994a, b). Previous studies in mammals using contralateral sound to stimulate the efferent system demonstrated a general suppressive effect on spontaneous and click-evoked, as well as on distortion-product otoacoustic emissions (DPOAE). As little is known about the effects of contralateral stimulation on hearing in birds, we studied the effect of such stimuli (broadband noise, pure tones) on the amplitude of the DPOAE 2f(1)-f(2) and on spontaneous otoacoustic emissions (SOAE) in the barn owl, Tyto alba. For the DPOAE measurements, fixed primary-tone pairs [f(1)=8.875 kHz (ratio=1.2), f(1)=8.353 kHz (ratio=1.15) and f(1)=7.889 kHz (ratio=1.1)] were presented and the DPOAE measured in the presence and absence of continuous contralateral stimulation. The DPOAE often declined in amplitude but in some cases we observed DPOAE enhancement. The changes in amplitude were as large as 9 dB. The influence of the contralateral noise changed over time, however, and the effects of contralateral tones were frequency-dependent. SOAE were suppressed in amplitude and shifted in frequency by contralateral broadband noise. Control measurements in animals after middle-ear muscle resection showed that these phenomena were not attributable to the acoustic middle-ear reflex. The finding of DPOAE enhancement is interesting, because a type of efferent fiber that suppressed its discharge rate during stimulation has been described in birds (Kaiser and Manley, 1994).

  10. Chloroform extract of hog barn dust modulates skeletal muscle ryanodine receptor calcium-release channel (RyR1)

    Science.gov (United States)

    Tian, Chengju; Shao, Chun Hong; Fenster, Danielle S.; Mixan, Mark; Romberger, Debra J.; Toews, Myron L.

    2010-01-01

    Skeletal muscle weakness is a reported ailment in individuals working in commercial hog confinement facilities. To date, specific mechanisms responsible for this symptom remain undefined. The purpose of this study was to assess whether hog barn dust (HBD) contains components that are capable of binding to and modulating the activity of type 1 ryanodine receptor Ca2+-release channel (RyR1), a key regulator of skeletal muscle function. HBD collected from confinement facilities in Nebraska were extracted with chloroform, filtered, and rotary evaporated to dryness. Residues were resuspended in hexane-chloroform (20:1) and precipitates, referred to as HBDorg, were air-dried and studied further. In competition assays, HBDorg dose-dependently displaced [3H]ryanodine from binding sites on RyR1 with an IC50 of 1.5 ± 0.1 μg/ml (Ki = 0.4 ± 0.0 μg/ml). In single-channel assays using RyR1 reconstituted into a lipid bilayer, HBDorg exhibited three distinct dose-dependent effects: first it increased the open probability of RyR1 by increasing its gating frequency and dwell time in the open state, then it induced a state of reduced conductance (55% of maximum) that was more likely to occur and persist at positive holding potentials, and finally it irreversibly closed RyR1. In differentiated C2C12 myotubes, addition of HBD triggered a rise in intracellular Ca2+ that was blocked by pretreatment with ryanodine. Since persistent activation and/or closure of RyR1 results in skeletal muscle weakness, these new data suggest that HBD is responsible, at least in part, for the muscle ailment reported by hog confinement workers. PMID:20576841

  11. Nuclear reactor PBMR and cogeneration; Reactor nuclear PBMR y cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J. R.; Alonso V, G., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In recent years the nuclear reactor designs for the electricity generation have increased their costs, so that at the moment costs are managed of around the 5000 US D for installed kw, reason for which a big nuclear plant requires of investments of the order of billions of dollars, the designed reactors as modular of low power seek to lighten the initial investment of a big reactor dividing the power in parts and dividing in modules the components to lower the production costs, this way it can begin to build a module and finished this to build other, differing the long term investment, getting less risk therefore in the investment. On the other hand the reactors of low power can be very useful in regions where is difficult to have access to the electric net being able to take advantage of the thermal energy of the reactor to feed other processes like the water desalination or the vapor generation for the processes industry like the petrochemical, or even more the possible hydrogen production to be used as fuel. In this work the possibility to generate vapor of high quality for the petrochemical industry is described using a spheres bed reactor of high temperature. (Author)

  12. Breeder Reactors, Understanding the Atom Series.

    Science.gov (United States)

    Mitchell, Walter, III; Turner, Stanley E.

    The theory of breeder reactors in relationship to a discussion of fission is presented. Different kinds of reactors are characterized by the cooling fluids used, such as liquid metal, gas, and molten salt. The historical development of breeder reactors over the past twenty-five years includes specific examples of reactors. The location and a brief…

  13. Evolution of the tandem mirror reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, G.A.; Logan, B.G.

    1982-03-09

    We discuss the evolution of the tandem mirror reactor concept from the original conceptual reactor design (1977) through the first application of the thermal barrier concept to a reactor design (1979) to the beginning of the Mirror Advanced Reactor Study (1982).

  14. FASTER Test Reactor Preconceptual Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Belch, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, A. J. [Argonne National Lab. (ANL), Argonne, IL (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jin, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Mohamed, W. [Argonne National Lab. (ANL), Argonne, IL (United States); Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Passerini, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sumner, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Vilim, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hayes, S. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-03-31

    The FASTER test reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  15. FASTER test reactor preconceptual design report summary

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Belch, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jin, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Mohamed, W. [Argonne National Lab. (ANL), Argonne, IL (United States); Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Passerini, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sumner, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Vilim, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hayes, Steven [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-29

    The FASTER reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  16. ADAPTIVE CONTROL SYSTEM OF INDUSTRIAL REACTORS

    Directory of Open Access Journals (Sweden)

    Vyacheslav K. Mayevski

    2014-01-01

    Full Text Available This paper describes a mathematical model of an industrial chemical reactor for production of synthetic rubber. During reactor operation the model parameters vary considerably. To create a control algorithm performed transformation of mathematical model of the reactor in order to obtain a dependency that can be used to determine the model parameters are changing during reactor operation.

  17. Nuclear research reactors activities in INVAP

    Energy Technology Data Exchange (ETDEWEB)

    Ordonez, Juan Pablo [INVAP, Bariloche (Argentina)

    2013-07-01

    This presentation describes the different activities in the research reactor field that are being carried out by INVAP. INVAP is presently involved in the design of three new research reactors in three different countries. The RA-10 is a multipurpose reactor, in Argentina, planned as a replacement for the RA-3 reactor. INVAP was contracted by CNEA for carrying out the preliminary engineering for this reactor, and has recently been contracted by CNEA for the detailed engineering. CNEA groups are strongly involved in the design of this reactor. The RMB is a multipurpose reactor, planned by CNEN from Brazil. CNEN, through REDETEC, has contracted INVAP to carry out the preliminary engineering for this reactor. As the user requirements for RA-10 and RMB are very similar, an agreement was signed between Argentina and Brasil governments to cooperate in these two projects. The agreement included that both reactors would use the OPAL reactor in Australia, design and built by INVAP, as a reference reactor. INVAP has also designed the LPRR reactor for KACST in Saudi Arabia. The LPRR is a 30 kw reactor for educational purposes. KACST initially contracted INVAP for the engineering for this reactor and has recently signed the contract with INVAP for building the reactor. General details of these three reactors will be presented.

  18. Research on Improving the Capacity of Bulk Curing Barn%提高密集烤房烤能的研究

    Institute of Scientific and Technical Information of China (English)

    刘卫华; 董世峰; 宋子峰; 邱军; 肖鹏; 牛柱峰; 杨宏伟; 刘洪杰

    2011-01-01

    为提高密集烤房产能,达到减工降本、提高烘烤质量、增加烟农效益的目标,对10座3层密集烤房进行了"3改4"处理。结果表明,改造后同等大小的烤房装烟容量同比提高23.5%,烤能比改造前提高30%,干烟成本由改造前的1.94元/kg降至1.76元/kg,节能效果较为可观。烘烤时间增加了24 h,有力地促进了烟叶的后熟,提高了烟叶的品质,单位产量虽略有下降,但上等烟及中上等烟的比例均有较大提高,产值比改造前提高3.8%。%To improve the capacity of bulk curing barn and baking quality, we turned three-floor into four-floor bulk curing barns, which could cut down the cost and energy consumption. The results showed that, the capacity was 23.5% higher than before, the weight of flue-cured tobacco of one barn was 30% heavier than before. In terms of energy consumption, the cost of dry tobacco fell from 1.94 yuan/kg to 1.76 yuan/kg. Baking time extended,which promoted tobacco after-ripening, and improved the quality of tobacco. Though the output was less than before, the proportion of upper class and the mid-upper class, tobacco increased, Interest increased by 3.8%.

  19. 采运烤一体化烤房挂筐式烘烤烟叶的效应%Effects of Tobacco Harvesting Roast Integration Barn Basket Baking

    Institute of Scientific and Technical Information of China (English)

    刘久羽; 阚宏伟; 胡向丹; 张大斌; 孙建生; 邓泳; 张纪利

    2014-01-01

    In order to simplify the baking process of tobacco and reduce tobacco baking cost,the current widespread use of tobacco baking bulk curing barn was transformed and the tobacco harvesting roast basket type curing effect of hanging barn integration was studied in this paper.The results showed that logging roast integration barn basket baking could promote the transformation of tobacco inclusions and aroma precursors,promote the coordination of chemical composition,increase the content of neutral aroma substances and improve the proportion of high class leaf.it could save labor quantity 8.45,reduce baked cost 659.01 Yuan when baked fresh tobacco 4000 kg,and net income increased 939.01 Yuan each 600 kg dry tobacco.%为简化烟叶烘烤工作环节和降低烟叶烘烤成本,利用目前烟叶烘烤普遍使用的密集烤房进行改造,研究了烟叶采运烤一体化烤房的挂筐式烘烤效应。结果表明:采运烤一体化烤房挂筐式烘烤能够促进烟叶内含物和香气前体物质的转化,促进化学成分的协调性及中性香气物质的含量,提高上等烟叶比例。采烤4000 kg 鲜烟可节约用工数量8.45个,烟叶采烤成本降低659.01元;烤后干烟叶(600 kg)纯收入增加939.01元。

  20. Circulating testosterone and feather-gene expression of receptors and metabolic enzymes in relation to melanin-based colouration in the barn owl.

    Science.gov (United States)

    Béziers, Paul; Ducrest, Anne-Lyse; Simon, Céline; Roulin, Alexandre

    2017-09-01

    Knowledge of how and why secondary sexual characters are associated with sex hormones is important to understand their signalling function. Such a link can occur if i) testosterone participates in the elaboration of sex-traits, ii) the display of an ornament triggers behavioural response in conspecifics that induce a rise in testosterone, or iii) genes implicated in the elaboration of a sex-trait pleiotropically regulate testosterone physiology. To evaluate the origin of the co-variation between melanism and testosterone, we measured this hormone and the expression of enzymes involved in its metabolism in feathers of barn owl (Tyto alba) nestlings at the time of melanogenesis and in adults outside the period of melanogenesis. Male nestlings displaying smaller black feather spots had higher levels of circulating testosterone, potentially suggesting that testosterone could block the production of eumelanin pigments, or that genes involved in the production of small spots pleiotropically regulate testosterone production. In contrast, the enzyme 5α-reductase, that metabolizes testosterone to DHT, was more expressed in feathers of reddish-brown than light-reddish nestlings. This is consistent with the hypothesis that testosterone might be involved in the expression of reddish-brown pheomelanic pigments. In breeding adults, male barn owls displaying smaller black spots had higher levels of circulating testosterone, whereas in females the opposite result was detected during the rearing period, but not during incubation. The observed sex- and age-specific co-variations between black spottiness and testosterone in nestling and adult barn owls may not result from testosterone-dependent melanogenesis, but from melanogenic genes pleiotropically regulating testosterone, or from colour-specific life history strategies that influence testosterone levels. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. The cervical spine of the American barn owl (Tyto furcata pratincola: I. Anatomy of the vertebrae and regionalization in their S-shaped arrangement.

    Directory of Open Access Journals (Sweden)

    Markus Krings

    Full Text Available BACKGROUND: Owls possess an extraordinary neck and head mobility. To understand this mobility it is necessary to have an anatomical description of cervical vertebrae with an emphasis on those criteria that are relevant for head positioning. No functional description specific to owls is available. METHODOLOGY/PRINCIPAL FINDINGS: X-ray films and micro-CT scans were recorded from American barn owls (Tyto furcata pratincola and used to obtain three-dimensional head movements and three-dimensional models of the 14 cervical vertebrae (C1-C14. The diameter of the vertebral canal, the zygapophyseal protrusion, the distance between joint centers, and the pitching angle were quantified. Whereas the first two variables are purely osteological characteristics of single vertebrae, the latter two take into account interactions between vertebrae. These variables change in characteristic ways from cranial to caudal. The vertebral canal is wide in the cranial and caudal neck regions, but narrow in the middle, where both the zygapophyseal protrusion and the distance between joint centers are large. Pitching angles are more negative in the cranial and caudal neck regions than in the middle region. Cluster analysis suggested a complex regionalization. Whereas the borders (C1 and C13/C14 formed stable clusters, the other cervical vertebrae were sorted into 4 or 5 additional clusters. The borders of the clusters were influenced by the variables analyzed. CONCLUSIONS/SIGNIFICANCE: A statistical analysis was used to evaluate the regionalization of the cervical spine in the barn owl. While earlier measurements have shown that there appear to be three regions of flexibility of the neck, our indicators suggest 3-7 regions. These many regions allow a high degree of flexibility, potentially facilitating the large head turns that barn owls are able to make. The cervical vertebral series of other species should also be investigated using statistical criteria to further

  2. The Cervical Spine of the American Barn Owl (Tyto furcata pratincola): I. Anatomy of the Vertebrae and Regionalization in Their S-Shaped Arrangement

    Science.gov (United States)

    Krings, Markus; Nyakatura, John A.; Fischer, Martin S.; Wagner, Hermann

    2014-01-01

    Background Owls possess an extraordinary neck and head mobility. To understand this mobility it is necessary to have an anatomical description of cervical vertebrae with an emphasis on those criteria that are relevant for head positioning. No functional description specific to owls is available. Methodology/Principal findings X-ray films and micro-CT scans were recorded from American barn owls (Tyto furcata pratincola) and used to obtain three-dimensional head movements and three-dimensional models of the 14 cervical vertebrae (C1−C14). The diameter of the vertebral canal, the zygapophyseal protrusion, the distance between joint centers, and the pitching angle were quantified. Whereas the first two variables are purely osteological characteristics of single vertebrae, the latter two take into account interactions between vertebrae. These variables change in characteristic ways from cranial to caudal. The vertebral canal is wide in the cranial and caudal neck regions, but narrow in the middle, where both the zygapophyseal protrusion and the distance between joint centers are large. Pitching angles are more negative in the cranial and caudal neck regions than in the middle region. Cluster analysis suggested a complex regionalization. Whereas the borders (C1 and C13/C14) formed stable clusters, the other cervical vertebrae were sorted into 4 or 5 additional clusters. The borders of the clusters were influenced by the variables analyzed. Conclusions/Significance A statistical analysis was used to evaluate the regionalization of the cervical spine in the barn owl. While earlier measurements have shown that there appear to be three regions of flexibility of the neck, our indicators suggest 3–7 regions. These many regions allow a high degree of flexibility, potentially facilitating the large head turns that barn owls are able to make. The cervical vertebral series of other species should also be investigated using statistical criteria to further characterize

  3. Optimization of apparatus design and behavioral measures for the assessment of visuo-spatial learning and memory of mice on the Barnes maze.

    Science.gov (United States)

    O'Leary, Timothy P; Brown, Richard E

    2013-01-15

    We have previously shown that apparatus design can affect visual-spatial cue use and memory performance of mice on the Barnes maze. The present experiment extends these findings by determining the optimal behavioral measures and test procedure for analyzing visuo-spatial learning and memory in three different Barnes maze designs. Male and female C57BL/6J mice were trained with a stable or random escape hole location and the sensitivities (statistical power) of four commonly used measures of learning and three measures of memory to detect differences between these training procedures were compared on each maze design. A maze design with a large diameter and no wall was optimal, because mice showed a reliable use of extra-maze visual cues, visuo-spatial search strategies, and spatial memory. A maze design with a small diameter, surrounding wall, and intra-maze visual cues was the least sensitive for determining visuo-spatial learning and memory, because mice showed little evidence of extra-maze cue use. Errors, distance traveled, and hole deviation scores were more sensitive measures of learning than latency to find the escape hole. Measures based on locating the escape hole (primary measures) were more sensitive than measures based on entering the escape hole (total measures). Measures of memory had similar levels of sensitivity on each maze. This experiment demonstrates that both apparatus design and the behavioral measures used as indicators of learning and memory can influence the ability of the Barnes maze to detect visuo-spatial learning and memory impairments in mice.

  4. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of the Phase 1 effort was to demonstrate the technical feasibility of the Advanced Carbothermal Electric (ACE) Reactor concept. Unlike...

  5. Thermal Analysis for Mobile Reactor

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Mobile reactor design in the paper is consisted of two grades of thermal electric conversion. The first grade is the thermionic conversion inside the core and the second grade is thermocouple conversion

  6. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop the Advanced Carbothermal Electric (ACE) reactor to efficiently extract oxygen from lunar regolith. Unlike state-of-the-art carbothermal...

  7. Teaching About Nature's Nuclear Reactors

    CERN Document Server

    Herndon, J M

    2005-01-01

    Naturally occurring nuclear reactors existed in uranium deposits on Earth long before Enrico Fermi built the first man-made nuclear reactor beneath Staggs Field in 1942. In the story of their discovery, there are important lessons to be learned about scientific inquiry and scientific discovery. Now, there is evidence to suggest that the Earth's magnetic field and Jupiter's atmospheric turbulence are driven by planetary-scale nuclear reactors. The subject of planetocentric nuclear fission reactors can be a jumping off point for stimulating classroom discussions about the nature and implications of planetary energy sources and about the geomagnetic field. But more importantly, the subject can help to bring into focus the importance of discussing, debating, and challenging current thinking in a variety of areas.

  8. Reactor containment research and development

    Energy Technology Data Exchange (ETDEWEB)

    Weil, N. A.

    1963-06-15

    An outline is given of containment concepts, sources and release rates of energy, responses of containment structures, effects of projectiles, and leakage rates of radioisotopes, with particular regard to major reactor accidents. (T.F.H.)

  9. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, L.R.; Hayes, D.W.; Hunter, C.H.; Marter, W.L.; Moyer, R.A.

    1989-12-01

    This volume is a reactor operation environmental information document for the Savannah River Plant. Topics include meteorology, surface hydrology, transport, environmental impacts, and radiation effects. 48 figs., 56 tabs. (KD)

  10. Advanced Catalytic Hydrogenation Retrofit Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Reinaldo M. Machado

    2002-08-15

    Industrial hydrogenation is often performed using a slurry catalyst in large stirred-tank reactors. These systems are inherently problematic in a number of areas, including industrial hygiene, process safety, environmental contamination, waste production, process operability and productivity. This program proposed the development of a practical replacement for the slurry catalysts using a novel fixed-bed monolith catalyst reactor, which could be retrofitted onto an existing stirred-tank reactor and would mitigate many of the minitations and problems associated with slurry catalysts. The full retrofit monolith system, consisting of a recirculation pump, gas/liquid ejector and monolith catalyst, is described as a monolith loop reactor or MLR. The MLR technology can reduce waste and increase raw material efficiency, which reduces the overall energy required to produce specialty and fine chemicals.

  11. Unique features of space reactors

    Science.gov (United States)

    Buden, David

    Space reactors are designed to meet a unique set of requirements; they must be sufficiently compact to be launched in a rocket to their operational location, operate for many years without maintenance and servicing, operate in extreme environments, and reject heat by radiation to space. To meet these restrictions, operating temperatures are much greater than in terrestrial power plants, and the reactors tend to have a fast neutron spectrum. Currently, a new generation of space reactor power plants is being developed. The major effort is in the SP-100 program, where the power plant is being designed for seven years of full power, and no maintenance operation at a reactor outlet operating temperature of 1350 K.

  12. Jules Horowitz Reactor, basic design

    Energy Technology Data Exchange (ETDEWEB)

    Bergamaschi, Y.; Bouilloux, Y.; Chantoin, P.; Guigon, B.; Bravo, X.; Germain, C.; Rommens, M.; Tremodeux, P

    2003-07-01

    Since the shutdown of the SILOE reactor in 1997, the OSIRIS reactor has ensured the needs regarding technological irradiation at CEA including those of its industrial partners and customers. The Jules Horowitz Reactor will replace it. It has the ambition to provide the necessary nuclear data and maintain a fission research capacity in Europe after 2010. This capacity should be service-oriented. It will be established in Cadarache. The Jules Horowitz reactor will also: - represent a significant step in term of performances and experimental capabilities, - be designed with a high flexibility, in order to satisfy the current demand from European industry, research and be able to accommodate future requirements, - reach a high level of safety, according to the best current practice. This paper will present the main functionalities and the design options resulting from the 'preliminary design' studies. (authors)

  13. Remaining Sites Verification Package for the 132-F-1, 141-F Chronic Feeding Sheep Barn, Waste Site Reclassification Form 2006-029

    Energy Technology Data Exchange (ETDEWEB)

    L. M. Dittmer

    2006-08-23

    The 132-F-1 site is the former location of the 141-F Chronic Feeding Sheep Barn that was part of the experimental animal farm at the 100-F Area. It was an L-shaped concrete block building with a concrete floor and concrete animal pens located both inside and outside the building. The 141-F Building was demolished in 1977 following relocation of animal research to the 300 Area. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

  14. Solid State Reactor Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas

  15. 密集烤房在烤烟生产中的优势及效益分析%Advantage and Benefit Analysis of Bulk Curing Barn in Production of Flue-cured Tobacco

    Institute of Scientific and Technical Information of China (English)

    罗元雄; 蔡坤伦; 龚德勇

    2012-01-01

    The article introduces the baking technologies and main operating points of bulk curing barn in the production of flue -cured tobacco. The bulk curing barn possesses the advantages of less labor cost, lower energy consumption, better quality, higher economic benefit and so on. The author puts forward the following suggestions: expediting the construction of bulk curing barn in Anlong county of Guizhou province, enhancing the study on the curing technologies of tobacco leaf, and gradually completing the operational mode of tobacco leaf specialization baking.%介绍了密集式烤房的烘烤工艺、操作要点比较优势和应用效益,提出了加快贵州安龙县密集烤房建设,加大对烟叶烘烤的技术工艺研究,逐步完善烟叶专业化烘烤运行模式的建议.

  16. Reactor antineutrinos and nuclear physics

    Science.gov (United States)

    Balantekin, A. B.

    2016-11-01

    Short-baseline reactor neutrino experiments successfully measured the neutrino parameters they set out to measure, but they also identified a shape distortion in the 5-7 MeV range as well as a reduction from the predicted value of the flux. Nuclear physics input into the calculations of reactor antineutrino spectra needs to be better refined if this anomaly is to be interpreted as due to sterile neutrino states.

  17. Microchannel Reactors for ISRU Applications

    Science.gov (United States)

    Carranza, Susana; Makel, Darby B.; Blizman, Brandon; Ward, Benjamin J.

    2005-02-01

    Affordable planning and execution of prolonged manned space missions depend upon the utilization of local resources and the waste products which are formed in manned spacecraft and surface bases. Successful in-situ resources utilization (ISRU) will require component technologies which provide optimal size, weight, volume, and power efficiency. Microchannel reactors enable the efficient chemical processing of in situ resources. The reactors can be designed for the processes that generate the most benefit for each mission. For instance, propellants (methane) can be produced from carbon dioxide from the Mars atmosphere using the Sabatier reaction and ethylene can be produced from the partial oxidation of methane. A system that synthesizes ethylene could be the precursor for systems to synthesize ethanol and polyethylene. Ethanol can be used as a nutrient for Astrobiology experiments, as well as the production of nutrients for human crew (e.g. sugars). Polyethylene can be used in the construction of habitats, tools, and replacement parts. This paper will present recent developments in miniature chemical reactors using advanced Micro Electro Mechanical Systems (MEMS) and microchannel technology to support ISRU of Mars and lunar missions. Among other applications, the technology has been demonstrated for the Sabatier process and for the partial oxidation of methane. Microchannel reactors were developed based on ceramic substrates as well as metal substrates. In both types of reactors, multiple layers coated with catalytic material are bonded, forming a monolithic structure. Such reactors are readily scalable with the incorporation of extra layers. In addition, this reactor structure minimizes pressure drop and catalyst settling, which are common problems in conventional packed bed reactors.

  18. The resonance absorption controlled reactor

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.

    1977-07-01

    In this report a new method of reactor control based on tho isotopic moderator composition variation is studied, taking as a reference a D{sub 2}O/H{sub 2}O system. With this method an spectacular increment in the burn-up degree and a sensible reduction of the conventional control system is obtained. An important part of this work has been the detailed analysis of the parameters affecting the neutron spectrum in a heterogeneous reactor. (Author) 50 refs.

  19. Calculation of reactor antineutrino spectra in TEXONO

    CERN Document Server

    Chen Dong Liang; Mao Ze Pu; Wong, T H

    2002-01-01

    In the low energy reactor antineutrino physics experiments, either for the researches of antineutrino oscillation and antineutrino reactions, or for the measurement of abnormal magnetic moment of antineutrino, the flux and the spectra of reactor antineutrino must be described accurately. The method of calculation of reactor antineutrino spectra was discussed in detail. Furthermore, based on the actual circumstances of NP2 reactors and the arrangement of detectors, the flux and the spectra of reactor antineutrino in TEXONO were worked out

  20. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iwashige, Kengo

    1996-06-21

    In an LMFBR type reactor, partitions are disposed to a coolant channel at positions lower than the free liquid level, and the width of the partitions is adapted to have a predetermined condition. Namely, when low temperature fluid overflowing the wall of the coolant channel, flows down and collided against the free liquid surface in the coolant channel, since the dropping speed thereof is reduced abruptly, large pressure waves are caused by kinetic force of the low temperature fluid. However, if appropriate numbers of partitions having an appropriate shape are formed, the dropping speed of the low temperature fluid is moderated to reduce the pressure waves. In addition, since the pressure waves are dispersed to the circumferential and lateral directions of the coolant flow channel respectively, the propagation of the pressure waves can be prevented effectively. Further, when the flow of the low temperature fluid is changed to the circumferential direction, for example, by earthquakes, since the partitions act as members resisting against the circumferential change of the low temperature fluid, the change of the direction can be suppressed. (N.H.)

  1. Reactor Simulator Testing

    Science.gov (United States)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise J.

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  2. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  3. Tritium management in fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Galloway, T.R.

    1978-05-01

    This is a review paper covering the key environmental and safety issues and how they have been handled in the various magnetic and inertial confinement concepts and reference designs. The issues treated include: tritium accident analyses, tritium process control, occupational safety, HTO formation rate from the gas-phase, disposal of tritium contaminated wastes, and environmental impact--each covering the Joint European Tokamak (J.E.T. experiment), Tokamak Fusion Test Reactor (TFTR), Russian T-20, The Next Step (TNS) designs by Westinghouse/ORNL and General Atomic/ANL, the ANL and ORNL EPR's, the G.A. Doublet Demonstration Reactor, the Italian Fintor-D and the ORNL Demo Studies. There are also the following full scale plant reference designs: UWMAK-III, LASL's Theta Pinch Reactor Design (RTPR), Mirror Fusion Reactor (MFR), Tandem Mirror Reactor (TMR), and the Mirror Hybrid Reactor (MHR). There are four laser device breakeven experiments, SHIVA-NOVA, LLL reference designs, ORNL Laser Fusion power plant, the German ''Saturn,'' and LLL's Laser Fusion EPR I and II.

  4. Innovative hybrid biological reactors using membranes; Reactores biologico hibrido innovadores utilizando membranas

    Energy Technology Data Exchange (ETDEWEB)

    Diez, R.; Esteban-Garcia, A. L.; Florio, L. de; Rodriguez-Hernandez, L.; Tejero, I.

    2011-07-01

    In this paper we present two lines of research on hybrid reactors including the use of membranes, although with different functions: RBPM, biofilm reactors and membranes filtration RBSOM, supported biofilm reactors and oxygen membranes. (Author) 14 refs.

  5. Establishment of licensing process for development reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Yune, Young Gill; Kim, Woong Sik (and others)

    2006-02-15

    A study on licensing processes for development reactors has been performed to prepare the licensing of development reactors developed in Korea. The contents and results of the study are summarized as follows. The licensing processes for nuclear reactors in Korea, U.S.A., Japan, France, U.K., Canada, and IAEA were surveyed and analyzed to obtain technical bases necessary for establishing licensing processes applicable to development reactors in Korea. Based on the technical bases obtained the above analysis, the purpose, power output, and design characteristics of development reactors were analyzed in detail. The analysis results suggested that development reactors should be classified as a new reactor category (called as 'development reactor') separated from the current reactor categories such as the research reactor and the power reactor. Therefore, it is proposed to establish a new reactor category classified as 'development reactor' for the development reactors. And licensing processes, including licensing technical requirements, licensing document requirements, and other regulatory requirements, were also proposed for the development reactors. In order to institutionalize the licensing processes developed in this study, it is necessary to revise the current laws. Therefore, draft provisions of Atomic Energy Act, Enforcement Decree of the Atomic Energy Act, and Enforcement Regulation of the Atomic Energy Act have been developed for the preparation of the future legalization of the licensing processes proposed for the development reactors. Conclusively, a proposal of licensing processes and draft provisions of laws have been developed for the development reactors. The results proposed in this study can be applied directly to the licensing of the future development reactors. Furthermore, they will also contribute to establishing successfully the licensing processes of the development reactors.

  6. Repairing liner of the reactor; Reparacion del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

  7. Reactor Simulator Testing

    Science.gov (United States)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise Jon

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz. Keywords: fission, space power, nuclear, liquid metal, NaK.

  8. Experience alters the spatial tuning of auditory units in the optic tectum during a sensitive period in the barn owl.

    Science.gov (United States)

    Knudsen, E I

    1985-11-01

    The auditory spatial tuning of bimodal (auditory-visual) units in the optic tectum of the barn owl was altered by raising animals with one ear occluded. Changes in spatial tuning were assessed by comparing the location of a unit's auditory best area with that of its visual receptive field. As shown previously, auditory best areas are aligned with visual receptive fields in the tecta of normal birds (Knudsen, E. I. (1982) J. Neurosci. 2: 1177-1194). It was demonstrated in this study that, when birds were raised with one ear occluded, best areas and visual receptive fields were aligned only as long as the earplug was in place. When the earplug was removed, best areas and visual receptive fields became misaligned, indicating that a change in auditory spatial tuning had taken place during the period of occlusion. However, in a bird that received an earplug as an adult, no such alterations in auditory spatial tuning were observed; even after 1 year of monaural occlusion, auditory best areas and visual receptive fields were misaligned so long as the earplug was in place, and were aligned when the earplug was removed. These results suggest that exposure to abnormal localization cues modifies the auditory spatial tuning of tectal units only during a restricted, sensitive period early in development. After the earplug was removed from a juvenile bird that had been raised with an occluded ear, the initial misalignment between auditory best areas and visual receptive fields decreased gradually over a period of weeks. In contrast, when earplugs were removed from two adult birds that had been raised with monaural occlusions, auditory-visual misalignments persisted for as long as measurements were made, which was up to 1 year after earplug removal. These data indicate that auditory cues become permanently associated with locations in visual space during a critical period which draws to a close at about the age when the animal reaches adulthood. Horseradish peroxidase was

  9. A percepção de valor dos ativos entre o mundo real e o virtual: o caso Barnes and Noble

    Directory of Open Access Journals (Sweden)

    Dalton Schmitt Jr

    2002-01-01

    Full Text Available Uma das questões de grande debate no mercado de investimentos gira em torno da diferença entre a valorização e a volatilidade de ativos relacionados a empresas do mundo real e empresas do mundo virtual (nova economia. O maior fluxo as informações, a incerteza e a inexistência de um modelo de negócio vencedor na nova economia têm ampliado essa discussão ao longo dos anos. O presente artigo tem como objetivo analisar a valorização de ativos de empresas desses dois mundos (real e virtual de mesmo foco de negócio e voltadas ao mesmo mercado em relação aos seus principais índices financeiros e performance. Estar-se-ão analisando dois negócios com mesmo fim de mercado mas que, por estarem com posicionamentos diferentes, apresentam características diferenciadas no que se refere a valorização de mercado e performance financeira. Visando desenvolver tal objetivo, o artigo analisará as empresa Barnes & Noble, tradicional varejista do segmento de livros no mercado norte-americano, e a sua subsidiária Barnes & Noble.com.

  10. Improvement of Drying Temperature Control Method in Tobacco-Flue-Cured Barn%烤烟烘烤房干温度控制方法的改进

    Institute of Scientific and Technical Information of China (English)

    李英俊; 金珖龙

    2011-01-01

    为了提高烤烟烘烤房的干温度精度和烤烟的烘烤质量,降低耗煤量,对往复推动式烟叶烘烤仪的干温度的控制方法进行了改进.通过利用模糊控制技术控制推煤电动机工作时间和停止工作时间,实现了根据烘烤工艺的要求对烤烟烘烤房的干温度进行实时监测的精确控制目标.%To improve the precision of drying temperature control of tobacco-flue-cured barn and the quality of flue-cured tobacco,and to reduce coal consumption for flue-cured tobacco,the drying temperature control method for the flue-cured tobacco apparatus with reciprocating transport function was improved.The working time and halting time of a coal-transport electric motor were controlled by fuzzy control technology,with the technology above the real-time of the accuracy control of the drying temperature of tobacco flue-cured barn was realized.

  11. Reactivity determination in accelerator driven reactors using reactor noise analysis

    Directory of Open Access Journals (Sweden)

    Kostić Ljiljana 1

    2002-01-01

    Full Text Available Feynman-alpha and Rossi-alpha methods are used in traditional nuclear reactors to determine the subcritical reactivity of a system. The methods are based on the measurement of the mean value, variance and the covariance of detector counts for different measurement times. Such methods attracted renewed attention recently with the advent of the so-called accelerator driven reactors (ADS proposed some time ago. The ADS systems, intended to be used either in energy generation or transuranium transmutation, will use a subcritical core with a strong spallation source. A spallation source has statistical properties that are different from those traditionally used by radioactive sources. In such reactors the monitoring of the subcritical reactivity is very important, and a statistical method, such as the Feynman-alpha method, is capable of resolving this problem.

  12. Thermonuclear Reflect AB-Reactor

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The author offers a new kind of thermonuclear reflect reactor. The remarkable feature of this new reactor is a three net AB reflector, which confines the high temperature plasma. The plasma loses part of its energy when it contacts with the net but this loss can be compensated by an additional permanent plasma heating. When the plasma is rarefied (has a small density), the heat flow to the AB reflector is not large and the temperature in the triple reflector net is lower than 2000 - 3000 K. This offered AB-reactor has significantly less power then the currently contemplated power reactors with magnetic or inertial confinement (hundreds-thousands of kW, not millions of kW). But it is enough for many vehicles and ships and particularly valuable for tunnelers, subs and space apparatus, where air to burn chemical fuel is at a premium or simply not available. The author has made a number of innovations in this reactor, researched its theory, developed methods of computation, made a sample computation of typical pr...

  13. Heterogeneous Transmutation Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Bays

    2007-09-01

    The threshold-fission (fertile) nature of Am-241 is used to destroy this minor actinide by capitalizing upon neutron capture instead of fission within a sodium fast reactor. This neutron-capture and its subsequent decay chain leads to the breeding of even neutron number plutonium isotopes. A slightly moderated target design is proposed for breeding plutonium in an axial blanket located above the active “fast reactor” driver fuel region. A parametric study on the core height and fuel pin diameter-to-pitch ratio is used to explore the reactor and fuel cycle aspects of this design. This study resulted in both non-flattened and flattened core geometries. Both of these designs demonstrated a high capacity for removing americium from the fuel cycle. A reactivity coefficient analysis revealed that this heterogeneous design will have comparable safety aspects to a homogeneous reactor of comparable size. A mass balance analysis revealed that the heterogeneous design may reduce the number of fast reactors needed to close the current once-through light water reactor fuel cycle.

  14. Entropy Production in Chemical Reactors

    Science.gov (United States)

    Kingston, Diego; Razzitte, Adrián C.

    2017-06-01

    We have analyzed entropy production in chemically reacting systems and extended previous results to the two limiting cases of ideal reactors, namely continuous stirred tank reactor (CSTR) and plug flow reactor (PFR). We have found upper and lower bounds for the entropy production in isothermal systems and given expressions for non-isothermal operation and analyzed the influence of pressure and temperature in entropy generation minimization in reactors with a fixed volume and production. We also give a graphical picture of entropy production in chemical reactions subject to constant volume, which allows us to easily assess different options. We show that by dividing a reactor into two smaller ones, operating at different temperatures, the entropy production is lowered, going as near as 48 % less in the case of a CSTR and PFR in series, and reaching 58 % with two CSTR. Finally, we study the optimal pressure and temperature for a single isothermal PFR, taking into account the irreversibility introduced by a compressor and a heat exchanger, decreasing the entropy generation by as much as 30 %.

  15. Simplifying Microbial Electrosynthesis Reactor Design

    Directory of Open Access Journals (Sweden)

    Cloelle G.S. Giddings

    2015-05-01

    Full Text Available Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata, which reduces carbon dioxide to acetate. In traditional ‘H-cell’ reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a poteniostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs.

  16. Hanford reactor and separations facility advantages

    Energy Technology Data Exchange (ETDEWEB)

    1963-06-27

    This document describes the advantages and limitations of Hanford production facilities. In addition to summarizing the technical parameters of the reactors and separations plants and their mechanical features, the unique aspects of these facilities to the production of special materials in which the Commission may be interested have been discussed. As the primary difference between the B-C-D-DR-F-H reactors and the K reactors and the K reactors is in the number and length of process channels. This report is addressed primarily to the 2000-tube reactors. K reactor characteristics are within the range of lattice and flexibility parameters described.

  17. Imaging Fukushima Daiichi reactors with muons

    Directory of Open Access Journals (Sweden)

    Haruo Miyadera

    2013-05-01

    Full Text Available A study of imaging the Fukushima Daiichi reactors with cosmic-ray muons to assess the damage to the reactors is presented. Muon scattering imaging has high sensitivity for detecting uranium fuel and debris even through thick concrete walls and a reactor pressure vessel. Technical demonstrations using a reactor mockup, detector radiation test at Fukushima Daiichi, and simulation studies have been carried out. These studies establish feasibility for the reactor imaging. A few months of measurement will reveal the spatial distribution of the reactor fuel. The muon scattering technique would be the best and probably the only way for Fukushima Daiichi to make this determination in the near future.

  18. Fast breeder reactors an engineering introduction

    CERN Document Server

    Judd, A M

    1981-01-01

    Fast Breeder Reactors: An Engineering Introduction is an introductory text to fast breeder reactors and covers topics ranging from reactor physics and design to engineering and safety considerations. Reactor fuels, coolant circuits, steam plants, and control systems are also discussed. This book is comprised of five chapters and opens with a brief summary of the history of fast reactors, with emphasis on international and the prospect of making accessible enormous reserves of energy. The next chapter deals with the physics of fast reactors and considers calculation methods, flux distribution,

  19. A tubular focused sonochemistry reactor

    Institute of Scientific and Technical Information of China (English)

    ZHOU GuangPing; LIANG ZhaoFeng; LI ZhengZhong; ZHANG YiHui

    2007-01-01

    This paper presents a new sonochemistry reactor, which consists of a cylindrical tube with a certain length and piezoelectric transducers at tube's end with the longitudinal vibration. The tube can effectively transform the longitudinal vibration into the radial vibration and thereby generates ultrasound. Furthermore, ultrasound can be focused to form high-intensity ultrasonic field inside tube. The reactor boasts of simple structure and its whole vessel wall can radiate ultrasound so that the electroacoustic transfer efficiency is high. The focused ultrasonic field provides good condition for sonochemical reaction. The length of the reactor can be up to 2 meters, and liquids can pass through it continuously, so it can be widely applied in liquid processing such as sonochemistry.

  20. A compact Tokamak transmutation reactor

    Institute of Scientific and Technical Information of China (English)

    QiuLi-Jian; XiaoBing-Jia

    1997-01-01

    The low aspect ration tokamak is proposed for the driver of a transmutation reactor.The main parameters of the reactor core,neutronic analysis of the blanket are given>the neutron wall loading can be lowered from the magnitude order of 1 MW/m2 to 0.5MW/m2 which is much easier to reach in the near future,and the transmutation efficiency (fission/absorption ratio)is raised further.The blanket power density is about 200MW/m3 which is not difficult to deal with.The key components such as diverter and center conductor post are also designed and compared with conventional TOkamak,Finally,by comparison with the other drivers such as FBR,PWR and accelerator,it can be anticipated that the low aspect ratio transmutation reactor would be one way of fusion energy applications in the near future.