WorldWideScience

Sample records for sais precursores sobre

  1. Saied M Soliman

    Indian Academy of Sciences (India)

    Saied M Soliman. Articles written in Journal of Chemical Sciences. Volume 127 Issue 9 September 2015 pp 1547-1556. Molecular structure investigation and tautomerism aspects of ()-3-benzylideneindolin-2-one · Assem Barakat Abdullah Mohammed Al-Majid Mohammad Shahidul Islam M Ali Saied M Soliman ...

  2. Soomlase disainitud tool sai preemia

    Index Scriptorium Estoniae

    2005-01-01

    Isku OY disaineri Tapio Anttila loodud tool Haiku sai rahvusvahelisel disainikonkursil ADEX 2004 mööbli kategoorias Adex Silveri preemia. Mullu sai sama tool Chicago arhitektuuri- ja disainimuuseumi preemia Good Design Award

  3. "Viola" sai Jaapanis eripreemia

    Index Scriptorium Estoniae

    2000-01-01

    Eesti Joonisfilmi 3 filmi võistlesid Hiroshima rahvusvahelisel animafilmide festivalil : "Viola" : režissöör Priit Tender, "Armastuse võimalikkusest" : režissöör, stsenarist ja operaator Janno Põldma ja "Porgandite öö" : režissöör Priit Pärn. Neist "Viola" sai žürii eripreemia. Peapreemia sai Kanada "When the Day Breaks" : režissöörid Wendy Tilby ja Amanda Forbis

  4. Priit Tenderi film sai Dresdenis auhinna

    Index Scriptorium Estoniae

    2002-01-01

    Dresdeni 14. filmifestivali animafilmide kategoorias sai teise preemia Priit Tenderi joonisfilm "Mont Blanc". Peapreemia sai saksa režissööri Jonathan Hodgsoni film "Camouflage". Kolmas oli PÖFFi peaauhinna saanud Stepan Birjukovi "Sossedi". Osales ka Nukufilmis diplomitööna valminud Jelena Girlini "Guff"

  5. Animated Dreamsi grand prix' sai film dododest

    Index Scriptorium Estoniae

    2007-01-01

    Animafilmide festivali "Animated Dreams" (21.-25. XI kinos Sõprus) auhinnasaajad : peaauhinna sai LAV-i "Lugu sellest, kuidas" (autor The Blackheart Gang), Balti- ja Põhjamaade festivali auhinna sai Eesti "Kleit" (Mari-Liis Bassovskaja, Jelena Girlin)

  6. Development and validation of a stock addiction inventory (SAI).

    Science.gov (United States)

    Youn, HyunChul; Choi, Jung-Seok; Kim, Dai-Jin; Choi, Sam-Wook

    2016-01-01

    Investing in financial markets is promoted and protected by the government as an essential economic activity, but can turn into a gambling addiction problem. Until now, few scales have widely been used to identify gambling addicts in financial markets. This study aimed to develop a self-rating scale to distinguish them. In addition, the reliability and validity of the stock addiction inventory (SAI) were demonstrated. A set of questionnaires, including the SAI, south oaks gambling screen (SOGS), and DSM-5 diagnostic criteria, for gambling disorder was completed by 1005 participants. Factor analysis, internal consistency testing, t tests, analysis of variance, and partial correlation analysis were conducted to verify the reliability and validity of SAI. The factor analysis results showed the final SAI consisting of two factors and nine items. The internal consistency and concurrent validity of SAI were verified. The Cronbach's α for the total scale was 0.892, and the SAI and its factors were significantly correlated with SOGS. This study developed a specific scale for financial market investments or trading; this scale proved to be reliable and valid. Our scale expands the understanding of gambling addiction in financial markets and provides a diagnostic reference.

  7. Euroopa parimaks filmiks sai Michael Haneke "Valge lint" / Andres Laasik

    Index Scriptorium Estoniae

    Laasik, Andres, 1960-2016

    2009-01-01

    Euroopa Filmiakadeemia auhindadest: parima filmiauhinna sai Saksamaal Bochumis toimunud tseremoonial Michael Haneke "Valge lint", mille eest Haneke sai ka parima režissööri ja stsenaristi auhinna. Parimaks meesnäitlejaks pärjati Tahar Rahim ("Un Prophete"), parimaks naisnäitlejaks Kate Winslet ("The Reader"), publikupreemia sai Danny Boyle'i "Rentslimiljonär. Ka teistest võitjatest

  8. Simmul sai Anapas auhinna / Ilona Martson, Andres Laasik

    Index Scriptorium Estoniae

    Martson, Ilona, 1970-

    2002-01-01

    SRÜ ja Baltimaade 11. filmifestivalil Anapas sai parima meesnäitleja preemia Rain Simmul Nika osa eest Arvo Iho mängufilmis "Karu süda". Videoprogrammi grand prix sai Mikk Ranna animafilm "Sääsk ja hobune", samas märgiti ära ka Mark Soosaare "La Paloma"

  9. Jaak Kilmi "Inimkaamera" sai peaauhinna

    Index Scriptorium Estoniae

    2000-01-01

    Alternatiivfilmide festivalil "Pulss" sai peaauhinna Jaak Kilmi film "Inimkaamera", huumori eripreemia Andres Maimiku ja kollektiivi Suits filmid ja novaatorluse ning originaalsuse eest auhinnati kahte Asko Kase filmi

  10. Starman sai operaatoritest esimesena ISO-sertifikaadi

    Index Scriptorium Estoniae

    2005-01-01

    Eesti suurim kaabeltelevisioonioperaator Starman sai esimese Eesti kaabelleviettevõttena kvaliteedijuhtimissertifikaadi, mis ettevõtte klientidele tähendab kinnitust teenindusprotsesside heast tasemest

  11. Tanel Toom sai UNICA'l pronksi

    Index Scriptorium Estoniae

    2004-01-01

    66. ülemaailmsel mitteprofessionaalsete filmitegijate festivalil (World Festival of Non-professional Film Makers) Saksamaal Veitshöchheimis sai TPÜ III kursuse tudeng Tanel Toom oma filmiga "2.68" pronksmedali

  12. "Ird, K." sai Riias preemia

    Index Scriptorium Estoniae

    2011-01-01

    7. Balti teatrifestivalil Riias sai Tartu Uue Teatri juht Ivar Põllu auhinna lavastuse "Ird, K." kontseptsiooni ja helikujunduse eest ning näitleja Nero Urke Kaarel Irdi rolli eest. Von Krahli Teatri truppi hinnati aja ja ruumi loova käsitluse eest lavastuses "The End"

  13. Eesti lastefilm sai UNICEFi auhinna

    Index Scriptorium Estoniae

    2007-01-01

    A Film Eesti laste lühianimafilm (režissöörid Aina Järvine ja Meelis Arulepp) tunnistati parimaks haridus- ja sotsiaalteemaliseks filmiks 19.-22. aprillini Itaalias toimunud "Cartoons on the Bay" festivalil ja sai Pulcinella auhinna. Praegu luuakse selle filmi tegelastega telesarja

  14. Viin sai definitsiooni / Karina Loi

    Index Scriptorium Estoniae

    Loi, Karina

    2008-01-01

    17. dets. 2007 kiideti põllumajanduse ja kalanduse ministrite nõukogus heaks määrus piiritusjookide määratlemise, kirjeldamise, esitlemise ja märgistamise kohta ja viina definitsioon sai lõpliku kinnituse. Märgistamisreegleid tuleb järgida vastavalt ELi direktiivile 2000/13

  15. Aplicabilidade e eficiência de dois métodos de saneamento de paredes degradadas por umidade e sais a partir de uma revisão bibliográfica e de um estudo de caso

    OpenAIRE

    Ursula Gewehr

    2004-01-01

    Este estudo faz um levantamento das diversas origens da umidade e sais solúveis presentes em edificações, contribuindo para uma melhor avaliação das causas das manifestações patológicas originadas. Serão abordados, também, dois métodos de recuperação de paredes degradas pela umidade e sais, que são o sistema de revestimento de recuperação e a eletroosmose ativa. Para tanto, seguiram-se as sugestões feitas por Bianchin (1999) sobre um estudo de traços de argamassas de saneamento que obtiveram ...

  16. Eesti film metsaneenetsist sai Šveitsis auhinna

    Index Scriptorium Estoniae

    2003-01-01

    Sotsiaalantropoloogi ja etnoloogi Liivo Niglase dokumentaalfilm neenetsi kirjanikust, kes naasnud põhjapõdrakasvatuse juurde - "Jüri Vella maailm" - sai Šveitsi filmifestivalil "Visions du Reel" Maailma Loduskaitse Liidu auhinna

  17. Merkel Cell-Driven BDNF Signaling Specifies SAI Neuron Molecular and Electrophysiological Phenotypes.

    Science.gov (United States)

    Reed-Geaghan, Erin G; Wright, Margaret C; See, Lauren A; Adelman, Peter C; Lee, Kuan Hsien; Koerber, H Richard; Maricich, Stephen M

    2016-04-13

    The extent to which the skin instructs peripheral somatosensory neuron maturation is unknown. We studied this question in Merkel cell-neurite complexes, where slowly adapting type I (SAI) neurons innervate skin-derived Merkel cells. Transgenic mice lacking Merkel cells had normal dorsal root ganglion (DRG) neuron numbers, but fewer DRG neurons expressed the SAI markers TrkB, TrkC, and Ret. Merkel cell ablation also decreased downstream TrkB signaling in DRGs, and altered the expression of genes associated with SAI development and function. Skin- and Merkel cell-specific deletion of Bdnf during embryogenesis, but not postnatal Bdnf deletion or Ntf3 deletion, reproduced these results. Furthermore, prototypical SAI electrophysiological signatures were absent from skin regions where Bdnf was deleted in embryonic Merkel cells. We conclude that BDNF produced by Merkel cells during a precise embryonic period guides SAI neuron development, providing the first direct evidence that the skin instructs sensory neuron molecular and functional maturation. Peripheral sensory neurons show incredible phenotypic and functional diversity that is initiated early by cell-autonomous and local environmental factors found within the DRG. However, the contribution of target tissues to subsequent sensory neuron development remains unknown. We show that Merkel cells are required for the molecular and functional maturation of the SAI neurons that innervate them. We also show that this process is controlled by BDNF signaling. These findings provide new insights into the regulation of somatosensory neuron development and reveal a novel way in which Merkel cells participate in mechanosensation. Copyright © 2016 the authors 0270-6474/16/364362-15$15.00/0.

  18. SAI/EPRI Albedo Information Library

    International Nuclear Information System (INIS)

    Simmons, G.L.

    1979-03-01

    The SAI/EPRI Albedo Information Library (SAIL) is described. This description included the techniques used to develop the data and comparisons with albedo data. Albedo data are presented for Type 04 Concrete and Low Carbon Steel, the most common materials encountered in radiation streaming analysis. Applications of the SAIL data are presented and compared with experimental results

  19. Kaitseliidu kool sai hinnalise kingituse / Kaire Kozlov

    Index Scriptorium Estoniae

    Kozlov, Kaire

    2006-01-01

    Oma viiendat tegutsemisaastat tähistav Kaitseliidu kool sai sünnipäevakingiks kuueteistkümnest sülearvutist ning lisaseadmetest koosneva arvutiklassi, kinkijateks osaühing SmartLink ning Riigikaitse Edendamise Sihtasutus

  20. Jõgeva bussijaam sai liimpuidu kasutamise eripreemia

    Index Scriptorium Estoniae

    2009-01-01

    Konkursil Eesti Parim Puitehitis 2009 sai liimpuidu kasutamise eripreemia Jõgeva bussijaam, arhitektid Andres Lunge ja Mait Lauri firmast Lunge & Co OÜst. Peapreemia pälvis suvila Jõelähtmel, arhitekt Sten Ader büroost SKAD Arhitektid. Loetletud ka teisi auhinnalistele kohtadele tulnud töid

  1. OÜ Same sai tootearendustoetust / Riina Mägi

    Index Scriptorium Estoniae

    Mägi, Riina, 1957-

    2008-01-01

    Tabiveres põllu- ja teehooldusmasinaid tootev OÜ Same sai Ettevõtluse Arendamise Sihtasutuse kaudu üle poole miljoni krooni tootearendustoetust, mille abil töötab firma välja uue, senisest paindlikuma ja multifunktsionaalsema ketas-liivapuisturi

  2. Eesti lühifilm sai erootikapreemia

    Index Scriptorium Estoniae

    2005-01-01

    Itaalias Montecatini lühifilmide festivalil sai kategoorias "Eros in short films" parima filmi auhinna lühimängufilm "Ring" : stsenaristid : Andrus Tuisk, Urmas Lennuk, Kaur Kender : režissöör Andrus Tuisk : osades Lembit Ulfsak, Merle Palmiste ja Karl Annus : Tuisk Film - Parunid ja Vonid 2004

  3. Modelagem da intrusão da água de um rio com diferentes concentrações de sais

    Directory of Open Access Journals (Sweden)

    Gabriel C. Marino

    2015-01-01

    Full Text Available Para considerações de intrusão de água em meio subterrâneo a capilaridade, também entendida como força de sucção, é uma grandeza física que influencia a dinâmica do processo. Neste trabalho é apresentada uma investigação do comportamento do escoamento subterrâneo e as interações entre água doce e água salinizada na área de descarga de um rio. Objetivou-se realizar uma modelagem preditiva para identificar e representar o processo de intrusão das águas de um rio meio ao lençol freático comparando diferentes concentrações de sais nas águas do rio e águas subterrâneas. Como modelo conceitual foi definido um rio em região de descarga. A modelagem foi realizada no software SUTRA sendo o método de solução por elementos finitos. Observou-se a formação de uma camada de água doce sobre o lençol freático salinizado quando considerada intrusão de água doce. Para as considerações com intrusão de água salinizada foi identificada a formação de fingers. Os resultados do modelo possibilitaram identificar que a intrusão de água doce no lençol freático salinizado é dificultada pela presença de sais. A intrusão é mais difícil quanto maior a concentração de sais nas águas subterrâneas.

  4. Development of the safety analysis system - SAIS - application to the Kola nuclear power plant

    International Nuclear Information System (INIS)

    Balfanz, H.P.; Fuhrmann, C.; Neumann, L.; Rumpf, J.; Kubintsev, B.; Marakulin, I.; Shevelev, V.; Terekhov, I.

    1995-01-01

    The project was started in July 1991 and finished by the end of 1993. It was aimed at adapting SAIS to WWER-440/W213 plant design and operational procedures, demonstrating the possibilities of SAIS for safety evaluation and examining the system by plant personnel and a PSA team. The project covered -the use of data form as well as fault and event tree methods of SAIS, - a probabilistic assessment of the high pressure injection system in case of a small break loss-of-coolant accident, - a quantification of human error probabilities for operator actions to cool down the primary circuit in case of a small break loss-of-coolant accident when the high pressure injection system has failed and - a comparison of Russian and German operational procedures and safety documents used in the probabilistic analyses of the SAIS-Kola project. As a main result SAIS was found to be an appropriate tool to give assistance to the plant personnel on safety evaluation of the plant within the frame of reconstruction measures and on the establishment of a qualified reliability data collection system at Kola NPP. (orig./HP) [de

  5. Bi txitodun sai arrearen kabia Baztanen (Nafarroan

    Directory of Open Access Journals (Sweden)

    ELOSEGI ONANDIA, I., ELOSEGI IRURTIA, M.M.

    2010-01-01

    (Folin, 1893 saiak ehizatzeko leku egoki bezala agertzen bait da. Geroztik ordea, eta ia mende batez, ezezagun bilakatu da zientzialarientzat, 1971 urtean berriro ere bertan saiak kumatzen direla baieztatu zen arte. Urte horretatik aurrera hurbileko jarraipena egin zaio Itxusiko sai-arre koloniari.

  6. Viru Vesi sai ISO sertifikaadid / Külli Kriis

    Index Scriptorium Estoniae

    Kriis, Külli, 1961-

    2005-01-01

    Ilmunud ka: Severnoje Poberezhje 23. märts lk. 4. AS Viru Vesi sai Eestis teise vee-ettevõttena veevarustuse, kanalisatsiooni ning reoveepuhastuse teenuse pakkumise alal keskkonna- ja kvaliteedijuhtimissüsteemi sertifikaadid

  7. Eesti seosega film sai Rootsis neli auhinda

    Index Scriptorium Estoniae

    2005-01-01

    PÖFFi külalistena Rootsist Tallinna saabunud väliseestlased Andres Lokko ja Martin Luuk on stsenaristid rootsi režissööri Tomas Alfredsoni mängufilmile "Pruuni neli varjundit" ("Fyra nyanser av brunt"), mis sai äsja Rootsi Kuldse Põrnika filmiauhindade jagamisel neli auhinda

  8. "Kaali saladus" sai Ungaris preemia / Inge Pitsner

    Index Scriptorium Estoniae

    Pitsner, Inge

    2003-01-01

    Populaarteaduslik Eesti-Läti ühisfilm Kaali meteoriidiplahvatusest "Kaali saladus" : stsenarist ja režissöör Urmas E. Liiv : operaator Ago Ruus : produtsent Riho Västrik, sai teadusfilmide festivalil Szolnokis kolmanda koha. R. Västrik valmistab ette uut dokfilmi "Middendorffi jälgedes". Sama ka : Teleleht nr. 45, lk. 12

  9. Piilupart Donald sai tähe Hollywoodi kuulsuste alleel

    Index Scriptorium Estoniae

    2004-01-01

    Walt Disney joonistatud Piilupart ilmus ekraanile esmakordselt 1934. aastal joonisfilmis "Tark tibu". Nüüd sai ka tema Hollywoodi tähtede alleel oma staaritähe Miki-Hiire, Pluuto ja Daisy kõrvale

  10. Kuldse Palmioksa sai film iirlaste iseseisvusvõitlusest / Triin Tael

    Index Scriptorium Estoniae

    Tael, Triin

    2006-01-01

    Cannes'i filmifestivali võitjad. Kuldse Palmioksa võitis Ken Loachi mängufilm "Tuul, mis sasib odrapõldu" ("The Wind That Shakes the Barley"), Grand Prix' sai prantslase Bruno Dumonti film "Flandria" ("Flandres")

  11. Noor Eesti teadlane sai maineka Briti stipendiumi / Aive Sarjas

    Index Scriptorium Estoniae

    Sarjas, Aive

    2012-01-01

    Eesti Maaülikooli veterinaarmeditsiini ja loomakasvatuse instituudi doktorant Kristi Kernerist sai esimene inimene väljaspool Ühendkuningriiki, kelle loomade heaolu teemalist projekti autasustas Humane Slaughter Association prestiižsse Dorothy Sidley nimelise stipendiumiga

  12. Noormees sai Eesti Päevalehe abiga magistrikraadi / Piia Puuraid

    Index Scriptorium Estoniae

    Puuraid, Piia

    2013-01-01

    Eile sai magistrikraadi Marek Süld, kelle isa Mati Süld Eesti Päevalehest tasuta õpingud võitis. Eesti Päevaleht loosis 2010. aastal välja 13 tasuta Estonian Business Schooli bakalaureuse- või magistriprogrammi

  13. Pärnumaa väikesaar sai oma traktori / Silvi Kanoshina

    Index Scriptorium Estoniae

    Kanoshina, Silvi

    2005-01-01

    Ilmunud ka: Pärnu Postimees 10. sets, lk. 5. Tõstamaa vald ostis Manija saare rannaniitude korrastamiseks traktori, raha traktori ostmiseks sai vald Euroopa regionaalarengu fondist. Kaart: Manija saar

  14. CAMSHIFT Tracker Design Experiments With Intel OpenCV and SAI

    National Research Council Canada - National Science Library

    Francois, Alexandre R

    2004-01-01

    ... (including multi-modal) systems, must be specifically addressed. This report describes design and implementation experiments for CAMSHIFT-based tracking systems using Intel's Open Computer Vision library and SAI...

  15. "Detsembrikuumuse" helirežissöör sai Emmy

    Index Scriptorium Estoniae

    2008-01-01

    Hollywoodis töötav helirežissöör Solange S. Schwalbe sai septembris Los Angeleses toimunud 2007-2008 Creative Arts Primetime Emmys tseremoonial Emmy minisarja "John Adams" heliefektide eest. Tema meeskond helindas ka meie uue mängufilmi

  16. Avaliação dos Efeitos Toxicológicos e Ambientais de Nanopartículas de Sais de Prata

    Directory of Open Access Journals (Sweden)

    Francielle Tatiana Mathias

    2014-01-01

    Full Text Available As nanopartículas de sais de prata são compostos muito utilizados nas indústrias farmacêuticas e de cosméticos, além de seu uso hospitalar. Sua utilização, tanto em produtos comerciais como na medicina, e sua importante correlação com a saúde pública e meio ambiente despertaram grande interesse em ações diretas e indiretas sobre o ser humano. Particularmente as nanopartículas de sais de prata têm sido muito utilizadas como antimicrobianos na desinfecção de materiais hospitalares, desodorantes, materiais dentários, em próteses internas e cateteres intravenosos, e tem possibilitado a contaminação humana e ambiental. Seus efeitos, concentrações perigosas e valores aceitáveis como contaminante demandam estudos. Sua instabilidade frente a interações com outros produtos as torna de grande interesse em relação à contaminação e persistência no ambiente. Diversos trabalhos produzidos em nossos laboratórios demonstram a atividade desreguladora endócrina de vários produtos químicos contaminantes ambientais e prejudiciais à saúde humana. Deste modo buscou-se um levantamento das principais formas de uso, seus riscos e efeitos toxicológicos para a saúde pública e meio ambiente.

  17. Rapla kihelkonna auhinna sai Ilse Rahkema / Margus Mikomägi

    Index Scriptorium Estoniae

    Mikomägi, Margus, 1956-

    2009-01-01

    Rapla kihelkonna päeval 22. juulil sai Rapla kihelkonna auhinna Raikküla teadjanaine, koduloolane Ilse Rahkema. Kihelkonna auhind kujutab endast pronksist valmistatud Maarja Magdaleena kuju, mille autor on skulptor Tauno Kangro

  18. Adubos foliares quelatizados e sais na absorção de boro, manganês e zinco em laranjeira ?Pera?

    Directory of Open Access Journals (Sweden)

    Santos Carlos Henrique dos

    1999-01-01

    Full Text Available O presente trabalho teve como objetivo comparar a eficiência de formulações de adubos foliares quelatizados na absorção dos micronutrientes boro, manganês e zinco, com a aplicação convencional de sais em plantas de laranjeira ?Pera? (Citrus sinensis (L. Osbeck. Para tanto foi conduzido experimento nas dependências do Departamento de Ciência do Solo da Faculdade de Ciências Agronômicas UNESP/Campus de Botucatu, Estado de São Paulo. Utilizaram-se plantas de laranjeira ?Pera? (Citrus sinensis (L. Osbeck enxertadas sobre limoeiro ?Cravo? (Citrus limonia Osbeck, com 2 anos de idade, plantadas em caixas de 250 litros. Os adubos foliares utilizados foram: Grex Citros na dose de 1,0 mL L-1; Copas citros 2,0 mL L-1; Plantin Citros 1,0 mL L-1; Citrolino 2,0 mL L-1; Fertamin Citros 1,75 mL L-1; Yogen Citros 2,0 mL L-1; MS-2 1,0 mL L-1; Sais, Sais + 1,0 g L-1 de KCl e Sais substituindo o ZnSO4 pelo ZnCl2. O volume de aplicação, foi de 1 litro de calda planta-1. Em todos os tratamentos adicionou-se o espalhante adesivo do grupo químico dos alquifenoletoxilados a 0,03%. A amostragem das folhas foi realizada 30 dias após a aplicação dos tratamentos, coletando-se a 3a ou 4a folha de ramos vegetativos no início do florescimento, dos 4 quadrantes, localizados na região mediana da planta, totalizando 10 folhas por planta. A aplicação foliar de micronutrientes, favoreceu a absorção e resultou no aumento do teor foliar de Mn e Zn mas não de B, sendo que a presença de cloreto aumentou os teores de Zn na folhas de laranjeira ?Pera?, proporcionando maior absorção do que o sulfato e sulfato adicionado ao cloreto de potássio. Os resultados mostram, também, que os produtos quelatizados Yogen e MS-2, para as condições deste estudo, não foram eficientes como fontes fornecedoras de Mn.

  19. Doktorant sai loomade heaolu uurimise eest haruldase stipendiumi / Mari Aigro

    Index Scriptorium Estoniae

    Aigro, Mari

    2012-01-01

    Eesti Maaülikooli veterinaarmeditsiini ja loomakasvatuse instituudi doktorant Kristi Kernerist sai esimene inimene väljaspool Ühendkuningriiki, kelle loomade heaolu teemalist projekti autasustas Humane Slaughter Association prestiižsse Dorothy Sidley nimelise stipendiumiga

  20. USA juhtivpoliitik sai süüdistuse pettuses / Neeme Raud

    Index Scriptorium Estoniae

    Raud, Neeme, 1969-

    2005-01-01

    USA Kongressi vabariiklaste juht Tom DeLay astus ametist tagasi, kuna Texase osariigi Travise maakonna kohus esitas talle süüdistuse seotuse eest Texase valimiskampaania rahastamisskeemiga. Esindajatekoja uueks vabariiklaste juhiks sai Missouri osariigi kongresmen Roy Blunt

  1. Control and Autonomy—The SAIs in Norway, Denmark, and Germany as Watchdogs in an NPM-Era?

    DEFF Research Database (Denmark)

    Jantz, Bastian; Reichborn-Kjennerud, Kristin; Vrangbæk, Karsten

    2015-01-01

    on an evaluative role when judging NPM instruments. At the same time their emphasis on legality and compliance can be at odds with some of the operating principles in NPM. All in all the German SAI seems to be the most radical critic. This may be linked to the lack of openness of the German SAIs results that makes...... it more internally focused within a mindset of administrative accountability....

  2. Ahistajat tabada aidanud naine sai aumärgi / Agnes Kuus

    Index Scriptorium Estoniae

    Kuus, Agnes

    2005-01-01

    Justiitsministeerium tunnustas kodanikujulguse aumärgiga seitset inimest, kes on kaasa aidanud kurjategijate tabamisele, teiste seas sai aumärgi Ingrid Lepp, kes aitas politseil kinni püüda Pärnu rannas tegutsenud ahistaja. Vt. samas: Turvamees nabis kinni muukija; Noored jälitasid telefonivarast; Tõnu Timma; Gennadi Kulla; Rita Parel. Lisa: Autasu julgetele

  3. Karzai sai vähem kui kolmandiku küsitud rahast / Evelyn Kaldoja

    Index Scriptorium Estoniae

    Kaldoja, Evelyn, 1980-

    2008-01-01

    Pariisis toimuval Afganistani doonorite konverentsil 50 miljardit dollarit lisaraha nõutanud president Hamid Karzai sai esialgu 14 miljardit dollarit. Välisminister Urmas Paet lubas oma sõnavõtus, et Eesti suurendab oma abi

  4. Tejiendo vínculos: tres mecanismos socioadaptativos desplegados por el movimiento Sai Baba en Argentina

    Directory of Open Access Journals (Sweden)

    Rodolfo Puglisi

    2012-01-01

    Full Text Available Luego de presentar los caracteres fundamentales del armazón institucional de la Or - ganización Sri Sathya Sai Baba ( osss B , surgida en la India, y de bosquejar la historia del movimiento Sai Baba en Argentina, en este artículo presento las que denomino tres estrategias socioadaptativas puestas en juego por el movimiento para favorecer la acomodación de sus creencias al campo sociorreligioso argentino, es decir, examino cómo se tejen puentes simbólicos con el trasfondo cultural local a fin de lograr una identificación con los valores de la sociedad receptora.

  5. Establishing strategic alliance among hospitals through SAIS: a case study in Taiwan.

    Science.gov (United States)

    Hung, Won-Fu; Hwang, Hsin-Ginn; Liao, Chechen

    2005-01-01

    Due to a reformed healthcare insurance system and a gradually decreasing public affairs' budget by the government year by year, Central Taiwan Office (CTO), the Department of Health (DOH) in Taiwan, initiated a strategic alliance project of the hospitals subordinated to the DOH in November, 2001. This project was a five-year plan with an attempt to expand and develop three more strategic alliances covering the northern, southern and eastern regions of Taiwan respectively. Through a cooperative system, such an alliance allows the following: resource sharing, technique collaboration, marketing affiliations and so on. In order to decrease operation management costs and improve the quality of service at hospitals, the strategic alliance practice is supported by IS. We call this alignment the IS-enabled strategic alliance. All the IS-enabled functions are supported by the Strategic Alliance Information System (SAIS). In this article, the SAIS developed by the CTO of the DOH is introduced.

  6. Rain Simmul sai mehise näitleja auhinna / Lauri Kärk

    Index Scriptorium Estoniae

    Kärk, Lauri, 1954-

    2002-01-01

    Bakuu rahvusvaheline filmilmifestival "Ida-Lääs", kus Rain Simmul sai oma rolli eest Arvo Iho filmis "Karu süda" diplomi. Näidati ka Peeter Simmi mängufilmi "Head käed" ja Andres Maimiku - Jaak Kilmi tõsielufilmi "Isamaa ilu". "Karu süda" on saanud ka Jack Londoni nimelise parima stsenaariumiga filmi auhinna California filmifestivalil Wine Country

  7. Agar pronkssõduriga võitleja sai kanepisuitsetamise eest trahvi / Katrin Rohtla, Siim Randla

    Index Scriptorium Estoniae

    Rohtla, Katrin, 1966-

    2006-01-01

    Aktiivse pronkssõduri vastasena tuntust kogunud Isamaaliidu liige Kalev Rebane sai Läänemaal Peraküla rannas kanepi suitsetamise eest politseilt 9000 krooni trahvi. Isamaa ja Res Publica Liidu liikmed on teinud ettepaneku noormees erakonnast välja arvata. Lisa: Mille eest koostati protokoll?

  8. Hästi restaureeritud raekoda sai Euroopast kõrge tunnustuse / Askur Alas

    Index Scriptorium Estoniae

    Alas, Askur, 1973-

    2006-01-01

    Tallinna raekoda sai Euroopa Liidu ja Euroopa pärandkultuuri organisatsiooni Europa Nostra kultuuripärandi medali. Europa Nostra nõukogu liikme Karin Hallas-Murula sõnul arvestatakse auhindade jagamisel nii mälestise säilitamist kui ka kasutamist tänapäeval. Mainekas auhind on tunnustus Teddy Böcklerile, kellele raekoja restaureerimine oli elutööks. Lisatud Europa Nostra peapreemiad

  9. Robert Frazure mälestuspuu Sõpruse pargis sai graniitpotil tähistuse / Raivo Feldmann

    Index Scriptorium Estoniae

    Feldmann, Raivo

    2007-01-01

    Esimese USA suursaadiku sõjajärgses Eestis, Robert Frazure' mälestuspuu sai Sõpruse pargis tähise, vajaliku raha ettevõtmise heaks annetasid Ameerika Suursaatkonna töötajad, nende delegatsioon viibis Põltsamaal Sõpruse pargis toimunud üritusel

  10. Development of Safety Assessment Information System (SAIS)

    International Nuclear Information System (INIS)

    Park, Byung Shik; Lee, Kyung Jin; Lee, Byung Chul; Song, Tae Young; Lee, Chang Ho

    2007-01-01

    Many reports and documents about nuclear power plant safety analysis like a Periodic Safe Review (PSR), Periodic Safety Analysis (PSA) and Severe Accident Management Guideline (SAMG) come to be drawn up from KHNP. Since these are not arranged easy to look up, the systematic arrangement of data was necessary. The solution against hereupon is to store database, and it was developed with the name, SAIS, by FNC Tech. Co. together with NETEC KHNP. In this web program it is easy to manage (registration, search and statistics) data. And the authorized user can approach this system. This was developed, and was verified under the development environment of; - Web Server : Apache 2.2.5 - Program Language : PHP 5.2 - DBMS : Oracle 10g

  11. Development of Safety Assessment Information System (SAIS)

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Shik; Lee, Kyung Jin; Lee, Byung Chul [FNC Tech. Co. Ltd. SNU, Seoul (Korea, Republic of); Song, Tae Young; Lee, Chang Ho [KHNP, Daejeon (Korea, Republic of)

    2007-10-15

    Many reports and documents about nuclear power plant safety analysis like a Periodic Safe Review (PSR), Periodic Safety Analysis (PSA) and Severe Accident Management Guideline (SAMG) come to be drawn up from KHNP. Since these are not arranged easy to look up, the systematic arrangement of data was necessary. The solution against hereupon is to store database, and it was developed with the name, SAIS, by FNC Tech. Co. together with NETEC KHNP. In this web program it is easy to manage (registration, search and statistics) data. And the authorized user can approach this system. This was developed, and was verified under the development environment of; - Web Server : Apache 2.2.5 - Program Language : PHP 5.2 - DBMS : Oracle 10g.

  12. SAI Intelligent Systems Conference (IntelliSys) 2015

    CERN Document Server

    Kapoor, Supriya; Bhatia, Rahul

    2016-01-01

    This book is a remarkable collection of chapters covering a wider range of topics, including unsupervised text mining, anomaly and Intrusion Detection, Self-reconfiguring Robotics, application of Fuzzy Logic to development aid, Design and Optimization, Context-Aware Reasoning, DNA Sequence Assembly and Multilayer Perceptron Networks. The twenty-one chapters present extended results from the SAI Intelligent Systems Conference (IntelliSys) 2015 and have been selected based on high recommendations during IntelliSys 2015 review process. This book presents innovative research and development carried out presently in fields of knowledge representation and reasoning, machine learning, and particularly in intelligent systems in a more broad sense. It provides state - of - the - art intelligent methods and techniques for solving real world problems along with a vision of the future research.

  13. Presence of e-EDCs in surface water and effluents of pollution sources in Sai Gon and Dong Nai river basin

    Directory of Open Access Journals (Sweden)

    Tam Le Thi Minh

    2016-01-01

    Full Text Available This study aimed to assess the presence of estrogenic endocrine disrupting compounds (e-EDCs including estriol, bisphenol A (BPA, atrazine (ATZ, octylphenol, octylphenol diethoxylate, octylphenol triethoxylate, nonylphenol, Nonylphenol triethoxylate (NPE3, nonylphenol diethoxylate (NPE2 and 17β-estradiol in: (i Sai Gon and Dong Nai river waters which have been major raw water sources for drinking water supply for Ho Chi Minh City (HCMC and neighbouring provinces, and (ii water pollution sources located in their catchment basin. NPE3 and NPE2 were detected in most of the surface water samples. Concentrations of NPE3 were in a range of less than 5.9–235 ng L−1, whereas BPA was detected at significantly high concentrations in the dry season in canals in HCMC. In the upstream of Sai Gon and Dong Nai Rivers, ATZ concentrations were observed at water intake of water treatment plants served for HCMC water supply system. Similarly, high potential risk of NPE2 and NPE3 contamination at Phu Cuong Bridge near Hoa Phu water intake was identified. The significant correlation between NPE2, dissolved organic carbon and total nitrogen was found. Estrogenic equivalent or estrogenic activity of Sai Gon and Dong Nai Rivers was lower than those of the previous studies. Compared with other studies, e-EDCs of pollution in Sai Gon river basin were relatively low.

  14. First-line bevacizumab-based therapy in advanced non-squamous non-small-cell lung cancer : analysis of the Italian patients enrolled in the SAiL study.

    Science.gov (United States)

    Bearz, Alessandra; Passalacqua, Rodolfo; Alabiso, Oscar; Cinieri, Saverio; Gridelli, Cesare; Cravesana, Claudia; Crinò, Lucio

    2012-11-01

    First-line bevacizumab-based therapy has been shown to improve outcomes in patients with advanced non-squamous non-small-cell lung cancer (NSCLC). The recent international phase IV SAiL study (a Study of Avastin [bevacizumab] in combination with platinum-containing chemotherapy in patients with advanced or recurrent non-squamous cell Lung cancer) evaluated the safety and efficacy of bevacizumab combined with standard chemotherapy regimens in routine clinical practice. Here we report the results of a subanalysis of baseline characteristics and efficacy data for Italian patients enrolled in SAiL. In the SAiL study, patients with untreated locally advanced, metastatic or recurrent non-squamous NSCLC received bevacizumab (7.5 or 15 mg/kg) every 3 weeks plus chemotherapy for up to six cycles, followed by single-agent bevacizumab until disease progression. Efficacy was assessed in terms of time to disease progression (TTP) and overall survival (OS). The Italian intent-to-treat population comprised 215 patients from a SAiL population of 2212 patients. At baseline, Italian patients tended to have less advanced disease than the overall population. Thus, the proportion of patients at enrollment with tumour stage IIIb and IV was 23.7 and 76.3 %, respectively, for the Italian population versus 19.7 and 80.3 % for the whole SAiL population. In addition, a higher proportion of Italian patients had an Eastern Cooperative Oncology Group performance status of 0 (72.6 vs. 37.2 %) and the prevalence of co-morbid conditions was lower in Italian patients (59.5 % of Italian patients reported a co-morbid condition and 60.0 % were receiving non-oncological treatment compared with 73.3 and 73.4 %, respectively, of SAiL patients overall). The mean exposures to bevacizumab and to chemotherapy were comparable between the Italian patient group and overall patient population, although cisplatin doublets were more commonly employed in Italian patients whereas carboplatin doublets were more

  15. Kuidas sai kirjanik Mart Raud endale kirjanik Albert Kivikase maja? : [Tallinn, Vaarika 3] / Stepan Karja

    Index Scriptorium Estoniae

    Karja, Stepan

    1995-01-01

    Vastukaja : Raud, Valda; Raud, Anu. Vastuseks Stepan Karja artiklile 'Kuidas sai kirjanik Mart Raud endale kirjanik Albert Kivikase maja' // Postimees, 1995, 18.apr., lk.7 ; Rebane, Ilme. Alati on raske loobuda armsaks saanud elupaigast // Postimees, 1995, 25.mai, lk.6

  16. Environmental impact assessment of radionuclide and metal contamination at the former U site at Kadji Sai, Kyrgyzstan.

    Science.gov (United States)

    Lind, O C; Stegnar, P; Tolongutov, B; Rosseland, B O; Strømman, G; Uralbekov, B; Usubalieva, A; Solomatina, A; Gwynn, J P; Lespukh, E; Salbu, B

    2013-09-01

    During 1949-1967, a U mine, a coal-fired thermal power plant and a processing plant for the extraction of U from the produced ash were operated at the Kadji Sai U mining site in Tonsk district, Issyk-Kul County, Kyrgyzstan. The Kadji Sai U legacy site represents a source of contamination of the local environment by naturally occurring radionuclides and associated trace elements. To assess the environmental impact of radionuclides and trace metals at the site, field expeditions were performed in 2007 and 2008 by the Joint collaboration between Norway, Kazakhstan, Kyrgyzstan, Tajikistan (JNKKT) project and the NATO SfP RESCA project. In addition to in situ gamma and Rn dose rate measurements, sampling included at site fractionation of water and sampling of water, fish, sediment, soils and vegetation. The concentrations of radionuclides and trace metals in water from Issyk-Kul Lake were in general low, but surprisingly high for As. Uptake of U and As was also observed in fish from the lake with maximum bioconcentration factors for liver of 1.6 and 75, respectively. The concentrations of U in water within the Kadji Sai area varied from 0.01 to 0.05 mg/L, except for downstream from the mining area where U reached a factor of 10 higher, 0.2 mg/L. Uranium concentrations in the drinking water of Kadji Sai village were about the level recommended by the WHO for drinking water. The (234)U/(238)U activity ratio reflected equilibrium conditions in the mining pond, but far from equilibrium outside this area (reaching 2.3 for an artesian well). Uranium, As and Ni were mainly present as low molecular mass (LMM, less than 10 kDa) species in all samples, indicating that these elemental species are mobile and potentially bioavailable. The soils from the mining sites were enriched in U, As and trace metals. Hot spots with elevated radioactivity levels were easily detected in Kadji Sai and radioactive particles were observed. The presence of particles carrying significant amount of

  17. Environmental impact assessment of radionuclide and metal contamination at the former U site at Kadji Sai, Kyrgyzstan

    International Nuclear Information System (INIS)

    Lind, O.C.; Stegnar, P.; Tolongutov, B.; Rosseland, B.O.; Strømman, G.; Uralbekov, B.; Usubalieva, A.; Solomatina, A.; Gwynn, J.P.; Lespukh, E.; Salbu, B.

    2013-01-01

    During 1949–1967, a U mine, a coal-fired thermal power plant and a processing plant for the extraction of U from the produced ash were operated at the Kadji Sai U mining site in Tonsk district, Issyk-Kul County, Kyrgyzstan. The Kadji Sai U legacy site represents a source of contamination of the local environment by naturally occurring radionuclides and associated trace elements. To assess the environmental impact of radionuclides and trace metals at the site, field expeditions were performed in 2007 and 2008 by the Joint collaboration between Norway, Kazakhstan, Kyrgyzstan, Tajikistan (JNKKT) project and the NATO SfP RESCA project. In addition to in situ gamma and Rn dose rate measurements, sampling included at site fractionation of water and sampling of water, fish, sediment, soils and vegetation. The concentrations of radionuclides and trace metals in water from Issyk-Kul Lake were in general low, but surprisingly high for As. Uptake of U and As was also observed in fish from the lake with maximum bioconcentration factors for liver of 1.6 and 75, respectively. The concentrations of U in water within the Kadji Sai area varied from 0.01 to 0.05 mg/L, except for downstream from the mining area where U reached a factor of 10 higher, 0.2 mg/L. Uranium concentrations in the drinking water of Kadji Sai village were about the level recommended by the WHO for drinking water. The 234 U/ 238 U activity ratio reflected equilibrium conditions in the mining pond, but far from equilibrium outside this area (reaching 2.3 for an artesian well). Uranium, As and Ni were mainly present as low molecular mass (LMM, less than 10 kDa) species in all samples, indicating that these elemental species are mobile and potentially bioavailable. The soils from the mining sites were enriched in U, As and trace metals. Hot spots with elevated radioactivity levels were easily detected in Kadji Sai and radioactive particles were observed. The presence of particles carrying significant amount of

  18. Kärstna lõvikuju sai käpa jälle tagasi / Aivar Aotäht

    Index Scriptorium Estoniae

    Aotäht, Aivar, 1970-

    2007-01-01

    Kärstna Kabelimäel asuv malmist lõvikuju sai eelmisel aastal varastatu asemele uue käpa. Modelleeris skulptor Paul Uibopuu. Kunstimälestisena muinsuskaitse all olev lõvikuju pandi Kabelimäele 1844. aastal kindralleitnant Reinhold von Anrepi mälestuseks

  19. Force sensor in simulated skin and neural model mimic tactile SAI afferent spiking response to ramp and hold stimuli.

    Science.gov (United States)

    Kim, Elmer K; Wellnitz, Scott A; Bourdon, Sarah M; Lumpkin, Ellen A; Gerling, Gregory J

    2012-07-23

    The next generation of prosthetic limbs will restore sensory feedback to the nervous system by mimicking how skin mechanoreceptors, innervated by afferents, produce trains of action potentials in response to compressive stimuli. Prior work has addressed building sensors within skin substitutes for robotics, modeling skin mechanics and neural dynamics of mechanotransduction, and predicting response timing of action potentials for vibration. The effort here is unique because it accounts for skin elasticity by measuring force within simulated skin, utilizes few free model parameters for parsimony, and separates parameter fitting and model validation. Additionally, the ramp-and-hold, sustained stimuli used in this work capture the essential features of the everyday task of contacting and holding an object. This systems integration effort computationally replicates the neural firing behavior for a slowly adapting type I (SAI) afferent in its temporally varying response to both intensity and rate of indentation force by combining a physical force sensor, housed in a skin-like substrate, with a mathematical model of neuronal spiking, the leaky integrate-and-fire. Comparison experiments were then conducted using ramp-and-hold stimuli on both the spiking-sensor model and mouse SAI afferents. The model parameters were iteratively fit against recorded SAI interspike intervals (ISI) before validating the model to assess its performance. Model-predicted spike firing compares favorably with that observed for single SAI afferents. As indentation magnitude increases (1.2, 1.3, to 1.4 mm), mean ISI decreases from 98.81 ± 24.73, 54.52 ± 6.94, to 41.11 ± 6.11 ms. Moreover, as rate of ramp-up increases, ISI during ramp-up decreases from 21.85 ± 5.33, 19.98 ± 3.10, to 15.42 ± 2.41 ms. Considering first spikes, the predicted latencies exhibited a decreasing trend as stimulus rate increased, as is observed in afferent recordings. Finally, the SAI afferent's characteristic response

  20. MONITORAMENTO DE SAIS NA ÁGUA E NOS SOLOS IRRIGADOS DO PROJETO VEREDA GRANDE, PB

    Directory of Open Access Journals (Sweden)

    Ladilson de Souza Macêdo

    1998-04-01

    Full Text Available RESUMO Avaliaram-se a variabilidade temporal dos sais na água de irrigação e seus efeitos sobre os solos irrigados do Projeto Vereda Grande, em Boqueirão, PB, através de amostragem aleatória estratificada em três lotes de agricultores. Foram coletadas 66 amostras de solo e 33 de água, no período de janeiro de 1987 a dezembro de 1989, sendo que a água apresentou crescente risco de salinização ao longo do tempo, com elevados níveis de sódio e cloreto - 8,6 e 10,5 mmolc.L-1, respectivamente. A presença de solos Bruno Não Cálcico e Litólicos na área de captação do manancial impede a melhoria da qualidade da água, predispondo os solos irrigados à alcalinização. Dentre as lavouras exploradas pelos irrigantes, apenas as capineiras são moderadamente tolerantes à concentração salina na zona radicular. A presença significativa de bicarbonato (1 a 3,2 mmolc.L-1 na água restringe a prática da irrigação por aspersão devido, principalmente, às condições de alta evaporação, aridez do local e toxidez específica do sódio e cloreto em plantas sensíveis.

  1. Šampoonivõltsijast sai kardetud jäätmete töötleja / Mihkel Kärmas

    Index Scriptorium Estoniae

    Kärmas, Mihkel, 1974-

    2009-01-01

    OÜ Megonar omanik Ahto Laanemägi sai loa ladustada kuni 60 000 t tselluloositehase Estonian Cell jäätmeid Noonu külas Virumaal. Põllumajandusteadlane Valjo Masso on leidnud Estonian Celli jääkmudast ootamatuid keemilisi elemente, nt. raskmetalle. Austria labori hinnang Estonian Celli muda kohta

  2. SÍNTESIS IN SITU DE NANOPARTÍCULAS DE PLATA SOBRE FIBRAS DE FIQUE

    Directory of Open Access Journals (Sweden)

    Sergio Ovalle

    2014-07-01

    Full Text Available Se realizó la síntesis de un material nanocompuesto mediante la deposiciónin situ de nanopartículas (NPs de plata sobre fibras de Fique. La influencia de parámetros experimentales, como concentración del precursor, concentración del agente reductor y tiempos de inmersión de las fibras en la solución del precursor y del agente reductor, se evaluó en términos de recubrimiento, tamaño y dispersión del nanomaterial sobre la superficie. Los nanocompositos fueron caracterizados mediante espectroscopia de reflectancia difusa UV-Vis (RD, microscopía electrónica (FESEM y difracción de rayos X (DRX. El control de los parámetros experimentales mencionados permitió obtener un material que exhibe recubrimiento uniforme y completo de NPs sobre la superficie y tamaños promedio de NPs de 40 nm. 

  3. Safety and efficacy of first-line bevacizumab with chemotherapy in Asian patients with advanced nonsquamous NSCLC: results from the phase IV MO19390 (SAiL) study.

    Science.gov (United States)

    Tsai, Chun-Ming; Au, Joseph Siu-kie; Chang, Gee-Chen; Cheng, Ashley Chi-kin; Zhou, Caicun; Wu, Yi-long

    2011-06-01

    First-line treatment with bevacizumab combined with chemotherapy has been shown to improve outcomes in patients with advanced, nonsquamous non-small cell lung cancer (NSNSCLC) in phase III clinical trials. SAiL (MO19390), an open-label, multicenter, single-arm study, evaluated the safety and efficacy of first-line bevacizumab-based treatment in clinical practice. This report presents the results of a preplanned subanalysis of Asian patients enrolled in SAiL. Patients with untreated, locally advanced, metastatic or recurrent NSNSCLC received bevacizumab 7.5 or 15 mg/kg every 3 weeks plus chemotherapy for up to six cycles, followed by single-agent bevacizumab until disease progression. Eligibility criteria for SAiL permitted enrolment of a broad patient population. The primary end point was safety; secondary end points included time to disease progression and overall survival. The Asian intent-to-treat population comprised 314 of the 2212 patients enrolled in the SAiL trial. In the Asian subanalysis, patients received a median of nine cycles of bevacizumab, and the median follow-up was 16.4 months. The incidence of clinically significant adverse events (grade ≥3) of special interest was relatively low in this population (15.6% overall); proteinuria (7.6%), hypertension (4.8%), and bleeding (2.5%) were the most common. A total of five adverse events related to bevacizumab were reported as grade 5. Disease control rate was 94.1%, median time to disease progression was 8.3 months, and median overall survival was 18.9 months. The safety and efficacy of first-line bevacizumab-based treatment in Asian patients with advanced NSNSCLC is consistent with that demonstrated in phase III studies and in the overall SAiL population. There were no new safety signals.

  4. Estresse salino e uso de biofertilizantes como mitigadores dos sais nos componentes morfofisiológicos e de produção de glicófitas

    Directory of Open Access Journals (Sweden)

    José Lucínio de Oliveira Freire

    2016-06-01

    Full Text Available A salinidade elevada das águas de boa parte dos mananciais hídricos do semiárido do Nordeste brasileiro contribui para reduzir o potencial produtivo da maioria das culturas alimentícias e não alimentícias. O acúmulo de sais no solo, além de comprometer as propriedades físicas e quími­cas do meio edáfico, reduz o potencial osmótico da solução do solo, restringindo a disponibilidade de água, resultando em desbalanço nutricional e toxicidade, prejudicando os processos metabólicos e fisiológicos das plantas. O uso de condicionadores orgânicos do solo, como os biofertilizantes, vem sendo testado em glicófitas como ferramenta de ajustamento osmótico das plantas aos sais. Com isso, essa Revisão de Literatura objetivou relatar estudos que tratem do estresse salino e concatenar algumas experimentações com biofertilizantes utilizados para mitigarem os efeitos depressivos dos sais nos componentes morfofisiológicos e produtivos de plantas glicófitas.

  5. Efeito da qualidade da água de irrigação sobre os atributos físicos de um neossolo flúvico do Município de Quixeré, CE - Brasil

    Directory of Open Access Journals (Sweden)

    Raimundo Nonato de Assis Júnior

    2012-12-01

    Full Text Available A qualidade da água usada na irrigação é um fator decisivo para a produtividade dos cultivos e para a qualidade do solo no semiárido brasileiro. Foram avaliados os efeitos das concentrações salinas da água de duas fontes distintas (rio e poço raso sobre os atributos físicos: argila dispersa em água, grau de floculação, densidade e porosidade do solo, estabilidade e diâmetro médio ponderado de agregados estáveis em água de um Neossolo Flúvico Ta eutrófico, cultivado com a bananeira Musa sp. cv. Pacovan, durante os anos 2000/2001. A densidade do solo, a argila dispersa em água e o grau de floculação mostraram-se sensíveis aos incrementos de sais no solo irrigado com água da fonte poço. Os movimentos de contração e expansão do solo estudado, muito provavelmente, influenciaram as variações observadas na macroporosidade e estabilidade de agregados, pois as concentrações salinas das águas das duas fontes não foram suficientemente altas para alterar esses atributos físicos. O curto espaço de tempo em que o solo foi submetido à ação de agentes salinizadores pode ter diminuído e, ou, mascarado os efeitos dos sais sobre os processos de floculação e dispersão.

  6. Síntese e propriedades fotoluminescentes do óxido de cério dopado com magnésio

    Directory of Open Access Journals (Sweden)

    G. P. Casali

    2014-09-01

    Full Text Available Neste trabalho são investigadas as propriedades ópticas de fotoluminescência do óxido de cério dopado com magnésio na forma de pós para analisar a influência dos sais precursores dos íons de interesse sobre a morfologia e as propriedades ópticas e para avaliar as propriedades ópticas com excitação em diferentes comprimentos de onda na região do visível e ultravioleta. Os pós foram obtidos pelo método dos precursores poliméricos. A caracterização estrutural dos materiais obtidos foi feita por difração de raios X. A estrutura e a simetria dos materiais foram estudadas por espectrometria de espalhamento Raman. As curvas de transmissão foram avaliadas por espectroscopia eletrônica na região UV-Vis. As propriedades ópticas foram avaliadas por espectroscopia de fotoluminescência e a microestrutura por microscopia eletrônica de varredura

  7. Safety and efficacy of first-line bevacizumab combination therapy in Chinese population with advanced non-squamous NSCLC: data of subgroup analyses from MO19390 (SAiL) study.

    Science.gov (United States)

    Zhou, C C; Bai, C X; Guan, Z Z; Jiang, G L; Shi, Y K; Wang, M Z; Wu, Y L; Zhang, Y P; Zhu, Y Z

    2014-05-01

    Bevacizumab is a monoclonal antibody with high antitumor activity against malignant diseases. Previous studies have demonstrated the efficacy of first-line bevacizumab combination therapy in advanced, non-squamous non-small cell lung cancer (NS-NSCLC). SAiL (MO19390), an open-label, multicenter, single-arm study, evaluated the safety and efficacy of first-line bevacizumab-based treatment in clinical practice. This report presents the results of a subgroup analysis of Chinese patients enrolled in SAiL. Chemo-naive Chinese patients with locally advanced, metastatic or recurrent NSCLC were randomized to receive Bev 15 mg/kg every 3 weeks plus carboplatin + paclitaxel for maximum of six cycles, followed by single-agent bevacizumab until disease progression. The primary endpoint was safety. Secondary endpoints included time to progression and overall survival. The Chinese intent-to-treat (ITT) population consists of 198 Chinese patients, among whom 107 (54 %) were non-smokers and 90 (45.5 %) were female. The median cycle of bevacizumab administration was 10 and median duration of bevacizumab treatment was 29.5 weeks. Only eight cases of severe adverse events were observed in the study, which were deemed to be related to bevacizumab. The incidence of AEs over grade 3 in Chinese ITT patients was generally low (SAiL study. No new safety signals were reported.

  8. Effect of Gamma Irradiation to Yellow Flesh Watermelon cv. ''Huay Sai Thong''

    International Nuclear Information System (INIS)

    Puripunyavanich, Vichai

    2003-06-01

    Yellow flesh watermelon seeds cv. Huay Sai Thong was irradiated with gamma rays. The experiment has been shown LD 50 dose at 420 Gy and GR 50 dose at 480 Gy approximately. Seeds of watermelon irradiated at 200 and 400 Gy were sown to find out mutation characteristics. The growth rate of M 1 plants was lower than the normal one. In M 2 plants, some irradiated lines showed non-dark green stripe on surface of fruit. Genetic testing was done according to skin color on watermelon fruit. It was found that the normal stripe characteristic was dominant and non-stripe characteristic was recessive. The Short length vine characteristic was selected till M 7 generation. The two lines of non-stripe watermelon and two lines of normal-stripe watermelon were selected for short length vine characteristic

  9. Management of household waste on a farm in the municipality of Varre-Sai, RJ

    Directory of Open Access Journals (Sweden)

    Cristiano Peixoto Maciel

    2012-07-01

    Full Text Available The study presents a diagnostic about the waste generated in a rural property, proposes and develops actions to mitigate the wrong accommodation made by the residents of the property. To remediate the problems detected, partnerships were implemented with the Varre Sai city government, the owner of the property, and the farm residents. A task force to collect the waste was organized, earthworm containers were constructed, and lectures were given. The project also included an agreement with the local government to collect the waste and supply recipients to the nine families of sharecroppers. The domestic waste was correctly allocated as well as the organic waste derived from the crops.

  10. CARBÓN ACTIVADO: EFECTO DEL LAVADO CON ÁCIDO SULFÚRICO DEL PRECURSOR LIGNOCELULÓSICO, CUESCO DE PALMA AFRICANA, SOBRE LOS PROCESOS DE CARBONIZACIÓN Y ACTIVACIÓN.

    Directory of Open Access Journals (Sweden)

    Luisa Fernanda Navarrete

    2008-03-01

    Full Text Available Se realizan lavados controlados durante diferentes periodos de tiempo, 6 y 12 horas, con soluciones diluidas de ácido sulfúrico, 2, 5 y 10%, sobre el precursor lignocelulósico cuesco de palma africana, consiguiendo reducir en más del 50% el contenido de cenizas de dicho material, en las que los componentes inorgánicos, principalmente elementos como hierro y aluminio, influyen notablemente en lareacción de gasificación con CO2 durante la activación física.Se determinan las entalpías de inmersión en las muestras con mayor grado de activación con resultados que se encuentran entre el 2 y 10 J.g-1, y se comparan con los obtenidos para carbones activados resultantes de lavar el material de partida con agua en los mismos períodos de tiempo.

  11. Ionospheric earthquake precursors

    International Nuclear Information System (INIS)

    Bulachenko, A.L.; Oraevskij, V.N.; Pokhotelov, O.A.; Sorokin, V.N.; Strakhov, V.N.; Chmyrev, V.M.

    1996-01-01

    Results of experimental study on ionospheric earthquake precursors, program development on processes in the earthquake focus and physical mechanisms of formation of various type precursors are considered. Composition of experimental cosmic system for earthquake precursors monitoring is determined. 36 refs., 5 figs

  12. Effect of low-dose irradiation upon T cell subsets involved in the response of primed A/J mice to SaI cells

    International Nuclear Information System (INIS)

    Anderson, R.E.; Williams, W.L.; Tokuda, Sei

    1988-01-01

    A/Jax (A/J) mice primed to Sarcoma I (SaI) exhibit an augmented response in association with low-dose (0.15 Gy) irradiation. This phenomenon is best demonstrated in tumour neutralization (Winn assay) or cell transfer experiments utilizing mice depleted of thymus-derived (T) cells. It is particularly dependent upon the duration of priming and the growth characteristics of the tumour in the primary host. The importance of these two variables appears to relate to their influence upon the cell types responsible for the host response, and includes both an effector and a suppressor component. Radiation-induced inhibition of the suppressor component appears responsible for low-dose augmentation and results in injury to a T cell of the Lyt-1 - 2 + phenotype. In Winn assays employing equal numbers of immune spleen cells and SaI cells, the smallest tumours are associated with Lyt-1-positive (Lyt-1 + 2 - and Lyt-1 + 2 + ) cells and exposure to 0.15 Gy markedly inhibits their anti-SaI activity. Thus, even though the effect is in the opposite direction, both the effector and suppressor components of the anti-SaI response in A/J mice are exceedingly radiosensitive. (author)

  13. MO19390 (SAiL): bleeding events in a phase IV study of first-line bevacizumab with chemotherapy in patients with advanced non-squamous NSCLC.

    Science.gov (United States)

    Dansin, Eric; Cinieri, Saverio; Garrido, Pilar; Griesinger, Frank; Isla, Dolores; Koehler, Manfred; Kohlhaeufl, Martin

    2012-06-01

    The clinical benefit and safety profile associated with first-line bevacizumab with doublet chemotherapy in patients with advanced non-squamous non-small cell lung cancer (NSCLC) was established in two large phase III studies, E4599 and AVAiL. SAiL, a single-arm phase IV study, was conducted to evaluate bevacizumab with a range of first-line chemotherapy regimens in a routine oncology practice setting. This analysis of the SAiL data was undertaken to specifically evaluate bleeding adverse events (AEs) in this study, and to explore potential associations between bleeding and baseline patient and disease characteristics. In total, 2212 patients were evaluated. Bleeding AEs (any grade) occurred in 38.2% of patients (grade ≥ 3 bleeding AEs: 3.6%). Grade ≥ 3 pulmonary hemorrhage and central nervous system bleeding events were observed in 0.7% and 0.1% of patients, respectively. The incidence of grade ≥ 3 bleeding AEs was comparable across patient subgroups defined by central tumor location, tumor cavitation, histology, concomitant anticoagulation therapy and age. The majority (88.6%) of bleeding events resolved or improved, 10.2% persisted and 1.3% led to death; 10.2% of bleeding events required bevacizumab interruption or discontinuation. This analysis from the SAiL trial reaffirms a comparable incidence of clinically significant bleeding associated with first-line bevacizumab and chemotherapy as previous phase III studies in NSCLC patients despite less stringent first-line selection criteria. Grade ≥ 3 bleeding appears to be comparable when analyzed for patient and tumor characteristics, including tumor cavitation and concomitant anticoagulation therapy. Most bleeding events resolved or improved, and interruption/discontinuation of bevacizumab was infrequent in a standard oncology practice setting. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. Sensory analysis of fermented alcoholic beverages from jabuticaba produced in the city of Varre-Sai, RJ

    Directory of Open Access Journals (Sweden)

    Leticia Tinoco Gonçalves

    2014-08-01

    Full Text Available Jabuticaba (Myrciariasp is a fruit native to the Atlantic Forest, belonging to the Myrtaceae family, and commonly found in Brazil. It presents considerable economic potential because it can be consumed as raw fruit or processed food. In Varre-Sai, RJ, jabuticaba is strongly used in the industrialization of alcoholic beverages. The production of fermented alcoholic alternative is used to avoid waste, and make the most of the considerable nutritional value of the fruit. The content of anthocyanins in jabuticaba ranges from 310 and 315mg/100g, relatively high value compared to other fruits considered rich in antioxidants. Therefore, sensory analyses of jabuticaba alcoholic beverages produced in Varre-Sai can improve the quality of the product and potential sales. Given that the part of jabuticaba rich in phenolic compounds is the bark, the whole use of the fruit is the best alternative to take advantage of its benefits. Sensory analysis evaluated the acceptance of fermented alcoholic of Jabuticaba, in relation to its overall rating attributes, color, flavor and aroma, based on a 9-point hedonic scale, with ends named strongly disliked (1 and strongly liked (9; as well as purchase intention of tasters by a 5-point hedonic scale, with anchor points would certainly buy (5 and would not certainly buy (1. The results showed that the products had good acceptance and the fermented Sweet Tinto was rated best in all attributes, obtaining 90.18% frequency in the acceptance of hedonic scale, with respect to global acceptance. Even in the hypothetical situation of purchase, it received 74.5% of the votes in the good range of the scale. This shows that the alcoholic fermented beverages may be an alternative for the consumption of antioxidants, and that their production can improve the income of farmers as well as help avoid fruit wasting.

  15. Estudos sobre a toxicologia da ε-caprolactama

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Justo Bomfim

    2009-03-01

    Full Text Available A ε-caprolactama (CAP é um monômero precursor de polímeros denominados nylon 6. Esses polímeros destinam-se à produção de tapetes, vestuário e materiais plásticos tais como equipamentos, sistemas e componentes automotivos, conectores, além de embalagens plásticas. Resíduos de CAP podem migrar de embalagens plásticas de nylon 6 para os alimentos. Diante disso, foi de interesse realizar uma revisão dos efeitos relativos à exposição à CAP e o seu impacto sobre a saúde humana. Estudos epidemiológicos indicam a possibilidade da CAP causar inflamações oculares e cutâneas, além de irritações no sistema respiratório. Pode ocorrer ainda hipotensão, taquicardia, palpitações, rinorréia, ressecamento nasal, efeitos geniturinários e sobre a reprodução como distúrbios nas funções menstrual e ovariana, e complicações no parto; além de problemas neurológicos e hematológicos. Estudos com animais são consistentes com tais relatos. Os estudos de genotoxicidade in vitro e in vivo por via oral e intraperitoneal mostram em sua grande maioria, resultados negativos, bem como ausência de efeitos carcinogênicos em ratos e camundongos e sobre o desenvolvimento e reprodução em ratos e coelhos.ε -Caprolactam (CAP is a precursor monomer of nylon 6 polymers. Nylon 6 is used in the manufacture of carpets, clothes and plastic materials, such as equipment, systems and automotive components, connectors and plastic packaging. CAP residues can migrate from nylon 6 plastic packaging to foods. Given this fact, this review was realized concerning the effects of CAP exposure and its impact on human health. Epidemiological studies indicate that CAP could cause ocular, cutaneous and respiratory irritations, as well as hypotension, tachycardia, palpitations, rhinorrhea, nose dryness, neurological and blood problems, and genitourinary and reproductive effects, such as alterations in ovarian-menstrual functions and pregnancy

  16. Preparación de precursores de esteroides por métodos organocatalícos

    OpenAIRE

    Pérez López, César

    2013-01-01

    Las denominadas cetonas de Hajos-Parrish, en especial la que posee un resto etilo, son un intermedio de gran interés en la síntesis total de algunos esteroides de alto valor. La obtención de este compuesto con elevada enantioselectividad es objeto de estudio en este trabajo. Se presenta la puesta a punto de la síntesis del precursor tricarbonílico y una serie de estudios sobre el medio ideal de reacción para la ciclación enantioselectiva del compuesto, así como una serie de ensayos utilizando...

  17. Thermal evolution of nitrate precursors for processing of lanthanide perovskites

    Directory of Open Access Journals (Sweden)

    Kozhukharov, V. S.

    1998-12-01

    Full Text Available Studies on thermal decomposition of ceramic powder with a general formula of (La1-x Ba x (Co0.8 Fe0.2O3 have been achieved. Precursors as nitrate solutions with additive of EDTA as complexion agent are used for powder processing. The black powders obtained are dried and their thermal evolution up to 1000ºC has been investigated by Differential Thermal Analysis. The powders was analyzed by EDX and ICP- AES, as well. It was established that the powder compositions are very close to the nominal one. The resulting DTA, TA, TG and DTG curves are analyzed as function of the composition and heating rate applied. At polythermal scanning regime three regions the powder thermal evolution are discussed. The correlation dependence has been examined for both Sr- and Ba- doped multicomponent lanthanide samples. The multicomponent nature of the samples have been shown on the base of the thermal treatment applied and XRD phase control carried out.

    Se han realizado estudios sobre la descomposición térmica de polvos cerámicos de fórmula general (La1-x Ba x (Co0.8 Fe0.2O3. Se utilizaron como precursores soluciones de nitratos con EDTA como agente acomplejante. La evolución térmica del polvo negro obtenido se estudió hasta la temperatura de 1000 ºC por medio de análisis térmico diferencial. Los polvos se analizaron así mismo por EDX e ICP-A ES. Se estableció que la composición de los polvos esta muy próxima a la composición nominal. Se distingue tres regímenes en la evolución térmica. Se examina la dependencia con el contenido en lantanidas multicomponentes de pulsos con Sr y Ba. La naturaleza multicomponente se ha mostrado sobre la base del tratamiento térmico empleado y el análisis de las fases cristalinas.

  18. Precursors prior to type IIn supernova explosions are common: Precursor rates, properties, and correlations

    Energy Technology Data Exchange (ETDEWEB)

    Ofek, Eran O.; Steinbok, Aviram; Arcavi, Iair; Gal-Yam, Avishay; Tal, David; Ben-Ami, Sagi; Yaron, Ofer [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Shaviv, Nir J. [Racah Institute of Physics, The Hebrew University, 91904 Jerusalem (Israel); Kulkarni, Shrinivas R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Nugent, Peter E. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Kasliwal, Mansi M. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Cenko, S. Bradley [Astrophysics Science Division, NASA/Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Laher, Russ; Surace, Jason [Spitzer Science Center, California Institute of Technology, M/S 314-6, Pasadena, CA 91125 (United States); Bloom, Joshua S.; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Silverman, Jeffrey M. [Department of Astronomy, University of Texas, Austin, TX 78712 (United States)

    2014-07-10

    There is a growing number of Type IIn supernovae (SNe) which present an outburst prior to their presumably final explosion. These precursors may affect the SN display, and are likely related to poorly charted phenomena in the final stages of stellar evolution. By coadding Palomar Transient Factory (PTF) images taken prior to the explosion, here we present a search for precursors in a sample of 16 Type IIn SNe. We find five SNe IIn that likely have at least one possible precursor event (PTF 10bjb, SN 2010mc, PTF 10weh, SN 2011ht, and PTF 12cxj), three of which are reported here for the first time. For each SN we calculate the control time. We find that precursor events among SNe IIn are common: at the one-sided 99% confidence level, >50% of SNe IIn have at least one pre-explosion outburst that is brighter than 3 × 10{sup 7} L{sub ☉} taking place up to 1/3 yr prior to the SN explosion. The average rate of such precursor events during the year prior to the SN explosion is likely ≳ 1 yr{sup –1}, and fainter precursors are possibly even more common. Ignoring the two weakest precursors in our sample, the precursors rate we find is still on the order of one per year. We also find possible correlations between the integrated luminosity of the precursor and the SN total radiated energy, peak luminosity, and rise time. These correlations are expected if the precursors are mass-ejection events, and the early-time light curve of these SNe is powered by interaction of the SN shock and ejecta with optically thick circumstellar material.

  19. Mercury exposure in Munduruku Indians from the community of Sai Cinza, state of Para, Brazil

    International Nuclear Information System (INIS)

    Oliveira Santos, Elisabeth C. de; Maura de Jesus, Iracina; Camara, Volney e M.; Brabo, Edilson; Brito Loureiro, Edvaldo C.; Mascarenhas, Artur; Weirich, Judith; Ragio Luiz, Ronir; Cleary, David

    2002-01-01

    The objective of this cross-sectional study was to evaluate mercury exposure and health status among Munduruku Indians from the community of Sai inza, State of Para, Brazil. The population studied included 330 Indians, who submitted to a questionnaire, clinical exams, and collection of hair, blood, urine, and feces. Mercury was measured in hair and fish. Although no person was found to have overt mercury intoxication, the mean levels of mercury in hair were elevated (14.45 μg/g for children from 7 to 12 years ld, 15.70 μg/g for women between 14 and 44 years old, and 14.1 μg/g or the remaining population). Mercury levels in fish were below levels recommended by the World Health Organization, but rates of fish consumption ere high. These results place this indigenous population as a group under risk of mercury toxicity from the gold production

  20. ESTUDO ATRAVÉS DE RMN DE 13C NO ESTADO SÓLIDO SOBRE A SÍNTESE DE OXIDO DE GRAFITE UTILIZANDO DIFERENTES PRECURSORES GRAFÍTICOS

    Directory of Open Access Journals (Sweden)

    Mariana A. Vieira

    Full Text Available The influence of the structural and microstructural characteristics of graphitic precursors on the production of graphite oxide (GO is investigated in the present work. Six different graphitic precursors were used to produce GO following a modified Hummers method, namely: natural graphite, commercial lubricant graphite, milled graphite, graphite flakes, high-purity graphite and graphite recycled from Li-ion batteries. The products were characterized by X-ray diffraction (XRD, thermogravimetry, solid-state 13C nuclear magnetic resonance (NMR and scanning electron microscopy (SEM. 13C NMR spectra revealed the presence of epoxy, hydroxyl, carbonyl and lactol groups in the synthesized GOs. However, the oxidation degree of each product was found to be dependent on the average crystallite size (Lc and particle size of the graphitic precursors, with the best GO samples being produced from the milled graphite and the graphite recycled from ion-Li batteries. These results were rationalized in terms of the structural and microstructural differences among the graphitic precursors, as revealed by the XRD patterns and SEM images, evidencing the importance of the correct choice of the precursor aiming the achievement of a well-developed structure for the GO product.

  1. Meat flavor precursors and factors influencing flavor precursors--A systematic review.

    Science.gov (United States)

    Khan, Muhammad Issa; Jo, Cheorun; Tariq, Muhammad Rizwan

    2015-12-01

    Flavor is the sensory impression sensed by taste and smell buds and is a leading factor determining the meat quality and purchasing decision of the consumer. Meat flavor is characteristic of volatiles produced as a result of reactions of non-volatile components that are induced thermally. The water soluble compounds having low molecular weight and meat lipids are important precursors of cooked meat flavor. The Maillard reaction, lipid oxidation, and vitamin degradation are leading reactions during cooking which develop meat flavor from uncooked meat with little aroma and bloody taste. The pre-slaughter and postmortem factors like animal breed, sex, age, feed, aging and cooking conditions contribute to flavor development of cooked meat. The objective of this review is to highlight the flavor chemistry, meat flavor precursors and factors affecting meat flavor precursors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Pengaruh Kompetensi, Kompensasi, Dan Lingkungan Kerja Terhadap Kinerja Karyawan Melalui Motivasi Kerja Sebagai Variabel Intervening (Studi Kasus Pada Karyawan Bagian Produksi PT. Sai Apparel Industries Semarang)

    OpenAIRE

    Mudayana, Fansyuri Ilham; Suryoko, Sri

    2016-01-01

    Every company always requires its employees to provide the best contribution in the form of performance enhancement. However, the require is not enough if it is not supported by a performance boosters that provided by the company and employees themselves. The boosters are laborer competence, compensation, and good workplace which all of them will increase work motivation. Therefore, PT Sai Apparel Industries as one of the players in national textile industries, can use the result of this rese...

  3. The stream of precursors that colonizes the thymus proceeds selectively through the early T lineage precursor stage of T cell development

    Science.gov (United States)

    Benz, Claudia; Martins, Vera C.; Radtke, Freddy; Bleul, Conrad C.

    2008-01-01

    T cell development in the thymus depends on continuous colonization by hematopoietic precursors. Several distinct T cell precursors have been identified, but whether one or several independent precursor cell types maintain thymopoiesis is unclear. We have used thymus transplantation and an inducible lineage-tracing system to identify the intrathymic precursor cells among previously described thymus-homing progenitors that give rise to the T cell lineage in the thymus. Extrathymic precursors were not investigated in these studies. Both approaches show that the stream of T cell lineage precursor cells, when entering the thymus, selectively passes through the early T lineage precursor (ETP) stage. Immigrating precursor cells do not exhibit characteristics of double-negative (DN) 1c, DN1d, or DN1e stages, or of populations containing the common lymphoid precursor 2 (CLP-2) or the thymic equivalent of circulating T cell progenitors (CTPs). It remains possible that an unknown hematopoietic precursor cell or previously described extrathymic precursors with a CLP, CLP-2, or CTP phenotype feed into T cell development by circumventing known intrathymic T cell lineage progenitor cells. However, it is clear that of the known intrathymic precursors, only the ETP population contributes significant numbers of T lineage precursors to T cell development. PMID:18458114

  4. ESTUDIO DE LA PROTECCIÓN ANTICORROSIVA SOBRE ACERO DE BAJO CARBONO MEDIANTE TRATAMIENTO DE CONVERSIÓN QUÍMICA BASE CERIO COMO PREPARACIÓN DE SUPERFICIE

    OpenAIRE

    MATA GALLARDO, LUIS JAIME

    2014-01-01

    En este trabajo, se propone un tratamiento de conversión química base cerio sobre acero de bajo carbono para obtener un incremento en las propiedades de protección y ser utilizado como una preparación de superficie para un pintado posterior. El nitrato de cerio fue elegido como precursor y se utilizaron tres métodos para la obtención de películas sobre la superficie de acero al carbono. Las películas son formadas utilizando o no el H2O2, sin embargo, el papel del H2O2 es el de ...

  5. Ionic liquid and aqueous two-phase extraction based on salting-out coupled with high-performance liquid chromatography for the determination of seven rare ginsenosides in Xue-Sai-Tong injection.

    Science.gov (United States)

    Li, Lan-Jie; Jin, Yong-Ri; Wang, Xiao-Zhong; Liu, Ying; Wu, Qian; Shi, Xiao-Lei; Li, Xu-Wen

    2015-09-01

    A method of ionic liquid salt aqueous two-phase extraction coupled with high-performance liquid chromatography has been developed for the analysis of seven rare ginsenosides including Rg6 , F4 , 20(S)-Rg3 , 20(R)-Rg3 , Rk3 , Rk1 , and Rg5 in Xue-Sai-Tong injection. The injection was mixed with ionic liquid 1-butyl-3-methylimidazolium bromide aqueous solution, and a mixture was obtained. With the addition of sodium dodecyl sulfate and dipotassium phosphate into the mixture, the aqueous two-phase mixture was formed after ultrasonic treatment and centrifuged. Rare ginsenosides were extracted into the upper phase. To obtain a high extraction factors, various influences were considered systematically, such as the volume of ionic liquid, the category and amount of salts, the amount of sodium dodecyl sulfate, the pH value of system, and the time of ultrasonic treatment. Under the optimal condition, rare ginsenosides in Xue-Sai-Tong injection were enriched and detected, the recoveries of seven rare ginsenosides ranged from 90.05 to 112.55%, while relative standard deviations were lower than 2.50%. The developed method was reliable, rapid and sensitive for the determination of seven rare ginsenosides in the injections. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Preparation of superconductor precursor powders

    Science.gov (United States)

    Bhattacharya, Raghunath

    1998-01-01

    A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

  7. Toward a theory of precursors

    International Nuclear Information System (INIS)

    Freivogel, Ben; Giddings, Steven B.; Lippert, Matthew

    2002-01-01

    To better understand the possible breakdown of locality in quantum gravitational systems, we pursue the identity of precursors in the context of the anti-de Sitter/conformal field theory correspondence. Holography implies a breakdown of standard bulk locality which we expect to occur only at extremely high energy. We consider precursors that encode bulk information causally disconnected from the boundary and whose measurement involves nonlocal bulk processes. We construct a toy model of holography which encapsulates the expected properties of precursors and compare it with previous such discussions. If these precursors can be identified in the gauge theory, they are almost certainly Wilson loops, perhaps with decorations, but the relevant information is encoded in the high-energy sector of the theory and should not be observable by low energy measurements. This would be in accord with the locality bound, which serves as a criterion for situations where breakdown of bulk locality is expected

  8. The interrelationships of mathematical precursors in kindergarten.

    Science.gov (United States)

    Cirino, Paul T

    2011-04-01

    This study evaluated the interrelations among cognitive precursors across quantitative, linguistic, and spatial attention domains that have been implicated for math achievement in young children. The dimensionality of the quantity precursors was evaluated in 286 kindergarteners via latent variable techniques, and the contribution of precursors from each domain was established for small sums addition. Results showed a five-factor structure for the quantity precursors, with the major distinction being between nonsymbolic and symbolic tasks. The overall model demonstrated good fit and strong predictive power (R(2)=55%) for addition number combinations. Linguistic and spatial attention domains showed indirect relationships with outcomes, with their effects mediated by symbolic quantity measures. These results have implications for the measurement of mathematical precursors and yield promise for predicting future math performance. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Solid state {sup 13}C NMR study on the synthesis of graphite oxide from different graphitic precursors; Estudo atravéS de RMN de {sup 13}C no estado sólido sobre a síntese de oxido de grafite utilizando diferentes precursores grafíticos

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Mariana A.; Frasson, Carolina Maria R.; Costa, Tainara Luiza G.; Cipriano, Daniel F.; Schettino Junior, Miguel A.; Cunha, Alfredo G.; Freitas, Jair C.C., E-mail: marianaarpini@hotmail.com [Universidade Federal do Espírito Santo (UFES), Vitória, ES (Brazil). Lab. de Materiais Carbonosos e Cerâmicos

    2017-10-15

    The influence of the structural and microstructural characteristics of graphitic precursors on the production of graphite oxide (GO) is investigated in the present work. Six different graphitic precursors were used to produce GO following a modified Hummers method, namely: natural graphite, commercial lubricant graphite, milled graphite, graphite flakes, high-purity graphite and graphite recycled from Li-ion batteries. The products were characterized by X-ray diffraction (XRD), thermogravimetry, solid-state {sup 13}C nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM). {sup 13}C NMR spectra revealed the presence of epoxy, hydroxyl, carbonyl and lactol groups in the synthesized GOs. However, the oxidation degree of each product was found to be dependent on the average crystallite size (Lc) and particle size of the graphitic precursors, with the best GO samples being produced from the milled graphite and the graphite recycled from ion-Li batteries. These results were rationalized in terms of the structural and microstructural differences among the graphitic precursors, as revealed by the XRD patterns and SEM images, evidencing the importance of the correct choice of the precursor aiming the achievement of a well-developed structure for the GO product. (author)

  10. Preliminary Monitoring of Soil gas Radon in Potentially Active Faults, San Sai District, Chiang Mai Province, Thailand

    Science.gov (United States)

    Pondthai, P.; Udphuay, S.

    2013-05-01

    The magnitude of 5.1 Mw earthquake occurred in San Sai District, Chiang Mai Province, Thailand in December 2006 was considered an uncommon event due to the fact that there was no statistical record of such significant earthquake in the area. Therefore the earthquake might have been associated with a potentially active fault zone within the area. The objective of this study is to measure soil gas radon across this unknown fault zone within the Chiang Mai Basin, northern Thailand. Two profiles traversing the expected fault zone of soil gas radon measurements have been monitored, using TASTRAK solid state track nuclear detectors (SSNTDs). Radon signals from three periods of measurement show a distinctive consistent spatial distribution pattern. Anomalous radon areas along the profiles are connected to fault locations previously interpreted from other geophysical survey results. The increased radon signal changes from the radon background level with the signal-to-background ratio above 3 are considered anomalous. Such pattern of radon anomaly supports the existence of the faults. The radon measurement, therefore is a powerful technique in mapping active fault zone.

  11. Effects of cyclophosphamide and irradiation singly and in combination upon SaI growth in A/J mice

    International Nuclear Information System (INIS)

    Anderson, R.E.; Williams, W.L.; Tokuda, S.

    1987-01-01

    The effects of various doses of cyclophosphamide and low-dose (15 rads) radiation upon the size of tumors caused by 10(4) Sarcoma I (SaI) cells was determined. In intact A/Jax (A/J) recipients, the effect of the two agents singly and in combination was found to be dependent especially upon the dosage of cyclophosphamide and the time of its administration in relation to tumor inoculation. In cell transfer experiments to adult thymectomized, lethally irradiated, bone-marrow-restored (ATxXBM) mice, the effects of cyclophosphamide and irradiation appeared to be either overlapping (low dosages of cyclophosphamide) or additive (dosages of cyclophosphamide greater than or equal to 50 mg/kg), suggesting that the two agents exert their influence in dissimilar fashion, perhaps by injuring different cell types with the same basic function. The most pronounced conjoint effects are seen when low dosages of cyclophosphamide are given 3 days after the adoptive transfer of spleen cells from mice pretreated with low-dose irradiation. The implications of this observation with respect to immunotherapy are discussed

  12. The Sommerfeld precursor in photonic crystals

    NARCIS (Netherlands)

    Uitham, R; Hoenders, BJ

    2006-01-01

    We calculate the Sommerfeld precursor that results after transmission of a generic electromagnetic plane wave pulse with transverse electric polarization, through a one-dimensional rectangular N-layer photonic crystal with two slabs per layer. The shape of this precursor equals the shape of the

  13. Progress in molecular precursors for electronic materials

    Energy Technology Data Exchange (ETDEWEB)

    Buhro, W.E. [Washington Univ., St. Louis, MO (United States)

    1996-09-01

    Molecular-precursor chemistry provides an essential underpinning to all electronic-materials technologies, including photovoltaics and related areas of direct interest to the DOE. Materials synthesis and processing is a rapidly developing field in which advances in molecular precursors are playing a major role. This article surveys selected recent research examples that define the exciting current directions in molecular-precursor science. These directions include growth of increasingly complex structures and stoichiometries, surface-selective growth, kinetic growth of metastable materials, growth of size-controlled quantum dots and quantum-dot arrays, and growth at progressively lower temperatures. Continued progress in molecular-precursor chemistry will afford precise control over the crystal structures, nanostructures, and microstructures of electronic materials.

  14. Lessons learned on probabilistic methodology for precursor analyses

    Energy Technology Data Exchange (ETDEWEB)

    Babst, Siegfried [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Berlin (Germany); Wielenberg, Andreas; Gaenssmantel, Gerhard [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Garching (Germany)

    2016-11-15

    Based on its experience in precursor assessment of operating experience from German NPP and related international activities in the field, GRS has identified areas for enhancing probabilistic methodology. These are related to improving the completeness of PSA models, to insufficiencies in probabilistic assessment approaches, and to enhancements of precursor assessment methods. Three examples from the recent practice in precursor assessments illustrating relevant methodological insights are provided and discussed in more detail. Our experience reinforces the importance of having full scope, current PSA models up to Level 2 PSA and including hazard scenarios for precursor analysis. Our lessons learned include that PSA models should be regularly updated regarding CCF data and inclusion of newly discovered CCF mechanisms or groups. Moreover, precursor classification schemes should be extended to degradations and unavailabilities of the containment function. Finally, PSA and precursor assessments should put more emphasis on the consideration of passive provisions for safety, e. g. by sensitivity cases.

  15. Lessons learned on probabilistic methodology for precursor analyses

    International Nuclear Information System (INIS)

    Babst, Siegfried; Wielenberg, Andreas; Gaenssmantel, Gerhard

    2016-01-01

    Based on its experience in precursor assessment of operating experience from German NPP and related international activities in the field, GRS has identified areas for enhancing probabilistic methodology. These are related to improving the completeness of PSA models, to insufficiencies in probabilistic assessment approaches, and to enhancements of precursor assessment methods. Three examples from the recent practice in precursor assessments illustrating relevant methodological insights are provided and discussed in more detail. Our experience reinforces the importance of having full scope, current PSA models up to Level 2 PSA and including hazard scenarios for precursor analysis. Our lessons learned include that PSA models should be regularly updated regarding CCF data and inclusion of newly discovered CCF mechanisms or groups. Moreover, precursor classification schemes should be extended to degradations and unavailabilities of the containment function. Finally, PSA and precursor assessments should put more emphasis on the consideration of passive provisions for safety, e. g. by sensitivity cases.

  16. Sol-gel precursors and products thereof

    Science.gov (United States)

    Warren, Scott C.; DiSalvo, Jr., Francis J.; Weisner, Ulrich B.

    2017-02-14

    The present invention provides a generalizable single-source sol-gel precursor capable of introducing a wide range of functionalities to metal oxides such as silica. The sol-gel precursor facilitates a one-molecule, one-step approach to the synthesis of metal-silica hybrids with combinations of biological, catalytic, magnetic, and optical functionalities. The single-source precursor also provides a flexible route for simultaneously incorporating functional species of many different types. The ligands employed for functionalizing the metal oxides are derived from a library of amino acids, hydroxy acids, or peptides and a silicon alkoxide, allowing many biological functionalities to be built into silica hybrids. The ligands can coordinate with a wide range of metals via a carboxylic acid, thereby allowing direct incorporation of inorganic functionalities from across the periodic table. Using the single-source precursor a wide range of functionalized nanostructures such as monolith structures, mesostructures, multiple metal gradient mesostructures and Stober-type nanoparticles can be synthesized. ##STR00001##

  17. Precursor Mediated Synthesis of Nanostructured Silicas: From Precursor-Surfactant Ion Pairs to Structured Materials.

    Science.gov (United States)

    Hesemann, Peter; Nguyen, Thy Phung; Hankari, Samir El

    2014-04-11

    The synthesis of nanostructured anionic-surfactant-templated mesoporous silica (AMS) recently appeared as a new strategy for the formation of nanostructured silica based materials. This method is based on the use of anionic surfactants together with a co-structure-directing agent (CSDA), mostly a silylated ammonium precursor. The presence of this CSDA is necessary in order to create ionic interactions between template and silica forming phases and to ensure sufficient affinity between the two phases. This synthetic strategy was for the first time applied in view of the synthesis of surface functionalized silica bearing ammonium groups and was then extended on the formation of materials functionalized with anionic carboxylate and bifunctional amine-carboxylate groups. In the field of silica hybrid materials, the "anionic templating" strategy has recently been applied for the synthesis of silica hybrid materials from cationic precursors. Starting from di- or oligosilylated imidazolium and ammonium precursors, only template directed hydrolysis-polycondensation reactions involving complementary anionic surfactants allowed accessing structured ionosilica hybrid materials. The mechanistic particularity of this approach resides in the formation of precursor-surfactant ion pairs in the hydrolysis-polycondensation mixture. This review gives a systematic overview over the various types of materials accessed from this cooperative ionic templating approach and highlights the high potential of this original strategy for the formation of nanostructured silica based materials which appears as a complementary strategy to conventional soft templating approaches.

  18. Earthquakes: hydrogeochemical precursors

    Science.gov (United States)

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  19. Magnetic reconnection and precursor effect in coaxial discharge

    International Nuclear Information System (INIS)

    Masoud, M.M.; Soliman, H.M.; El-Khalafawy, T.A.

    1988-01-01

    A precursor pulse was observed ahead of the plasma sheath produced by a coaxial electrode discharge system. The velocity of the precursor pulse was 4x10 7 cmS -1 and the velocity of the plasma sheath was 6x10 6 cmS -1 . The precursor pulse was unaffected when an axial magnetic field of 6 K.G. was applied to the propagation chamber, while the plasma sheath velocity increased and downstream structure were changed. The precursor pulse was split, sometimes, into two or more peaks, had the same shape and structure of the original one. The rest gas was heated up to 20 e.V. when the precursor pulse was destructed. The precursor pulse propagation mechanism and parameters showed that it had a solitary wave structure and behaviour. A reversed magnetic field was detected, when the plasma sheath had diamagnetic properties, where magnetic reconnection took place. Magnetic reconnection was responsible for energy transfiguration and wave generation. This was due to acceleration mechanism of charged particles occurred by the induced electric field at the moment of magnetic reconnection. The detected induced electric field had a high field intensity and fast rise time pulse. Several instabilities were referred to magnetic reconnection and the precursor pulse observed was a result of such instabilities

  20. Mobilidade de cátions e correção da acidez de um Cambissolo em função da aplicação superficial de calcário combinado com sais de potássio Cation mobility and acidity decrease in a Haplumbrept due to surface liming combined with potassium fertilizers

    Directory of Open Access Journals (Sweden)

    Lisandra Pinto Della Flora

    2007-12-01

    Full Text Available A menor reatividade do calcário abaixo dos locais de aplicação deve-se principalmente à sua baixa solubilidade, ao aumento das cargas negativas nas camadas aplicadas devido ao aumento do pH e à pequena permanência dos ânions adicionados na solução do solo. O presente trabalho teve por objetivo avaliar o efeito da adição de ânions a partir de sais de K sobre a superfície do solo, no incremento da reatividade do calcário e na mobilidade de seus cátions em um Cambissolo Húmico. O experimento foi realizado em 2005, em solo com 360 g kg-1 de argila, 60 g kg-1 de matéria orgânica e pH 4,1. Foram utilizadas três doses de calcário dolomítico (0, 0,74 e 1,48 kg m-2, combinadas com 40 g m-2 de K, na forma de KCl ou de KNO3, e com uma testemunha sem K, todos incorporados no primeiro centímetro da coluna do solo. As unidades experimentais (colunas de PVC com 10 x 30 cm, contendo 1,5 kg de solo foram percoladas 21 vezes, a cada sete dias, com 300 mL de água destilada por semana, totalizando o equivalente a 800 mm de chuva. Os sais potássicos lixiviaram muito mais Ca e Mg do que o calcário. Na média dos três tratamentos de calagem, a adição dos sais aumentou a lixiviação total de Ca, Mg e K, respectivamente de 36 para 132 mg, de 5,8 para 26 mg e de 25 para 51 mg/coluna, relativamente ao tratamento sem adição de sal. Na ausência dos sais, a aplicação da maior dose de calcário dolomítico lixiviou apenas 5 mg de Ca e 1,2 mg/coluna de Mg, em relação ao tratamento sem calcário. A calagem superficial afetou o pH do solo e a concentração de Ca, Mg e Al trocável até a profundidade máxima de 5,0 cm, cujas alterações foram quase sempre proporcionais à dose aplicada, porém não foram influenciadas pela adição dos sais. A aplicação dos fertilizantes potássicos não influenciou a capacidade reativa do calcário aplicado na superfície do solo.The low reactivity of lime below the application layer is mainly due to its

  1. Enumeration of minimal stoichiometric precursor sets in metabolic networks.

    Science.gov (United States)

    Andrade, Ricardo; Wannagat, Martin; Klein, Cecilia C; Acuña, Vicente; Marchetti-Spaccamela, Alberto; Milreu, Paulo V; Stougie, Leen; Sagot, Marie-France

    2016-01-01

    What an organism needs at least from its environment to produce a set of metabolites, e.g. target(s) of interest and/or biomass, has been called a minimal precursor set. Early approaches to enumerate all minimal precursor sets took into account only the topology of the metabolic network (topological precursor sets). Due to cycles and the stoichiometric values of the reactions, it is often not possible to produce the target(s) from a topological precursor set in the sense that there is no feasible flux. Although considering the stoichiometry makes the problem harder, it enables to obtain biologically reasonable precursor sets that we call stoichiometric. Recently a method to enumerate all minimal stoichiometric precursor sets was proposed in the literature. The relationship between topological and stoichiometric precursor sets had however not yet been studied. Such relationship between topological and stoichiometric precursor sets is highlighted. We also present two algorithms that enumerate all minimal stoichiometric precursor sets. The first one is of theoretical interest only and is based on the above mentioned relationship. The second approach solves a series of mixed integer linear programming problems. We compared the computed minimal precursor sets to experimentally obtained growth media of several Escherichia coli strains using genome-scale metabolic networks. The results show that the second approach efficiently enumerates minimal precursor sets taking stoichiometry into account, and allows for broad in silico studies of strains or species interactions that may help to understand e.g. pathotype and niche-specific metabolic capabilities. sasita is written in Java, uses cplex as LP solver and can be downloaded together with all networks and input files used in this paper at http://www.sasita.gforge.inria.fr.

  2. Are any public-reported earthquake precursors valid?

    Directory of Open Access Journals (Sweden)

    N. E. Whitehead

    2004-01-01

    Full Text Available This article examines retrospective public-supplied precursor reports statistically, and confirms published hypotheses that some alleged precursors within 100km and within a day prior to the large 1995 Kobe and 1999 Izmit earthquakes, may be valid. The confirmations are mostly at the p<0.001 level of significance. Most significant were alleged meteorological and geophysical precursors, and less often, animal reports. The chi-squared test used, for the first time eliminates the distorting effects of psychological factors on the reports. However it also shows that correct reports are diluted with about the same number which are merely wishful thinking, and obtaining more reliable data would be logistically difficult. Some support is found for another published hypothesis in which other precursors occurred within the ten days prior to the earthquake.

  3. Precursor Mediated Synthesis of Nanostructured Silicas: From Precursor-Surfactant Ion Pairs to Structured Materials

    Directory of Open Access Journals (Sweden)

    Peter Hesemann

    2014-04-01

    Full Text Available The synthesis of nanostructured anionic-surfactant-templated mesoporous silica (AMS recently appeared as a new strategy for the formation of nanostructured silica based materials. This method is based on the use of anionic surfactants together with a co-structure-directing agent (CSDA, mostly a silylated ammonium precursor. The presence of this CSDA is necessary in order to create ionic interactions between template and silica forming phases and to ensure sufficient affinity between the two phases. This synthetic strategy was for the first time applied in view of the synthesis of surface functionalized silica bearing ammonium groups and was then extended on the formation of materials functionalized with anionic carboxylate and bifunctional amine-carboxylate groups. In the field of silica hybrid materials, the “anionic templating” strategy has recently been applied for the synthesis of silica hybrid materials from cationic precursors. Starting from di- or oligosilylated imidazolium and ammonium precursors, only template directed hydrolysis-polycondensation reactions involving complementary anionic surfactants allowed accessing structured ionosilica hybrid materials. The mechanistic particularity of this approach resides in the formation of precursor-surfactant ion pairs in the hydrolysis-polycondensation mixture. This review gives a systematic overview over the various types of materials accessed from this cooperative ionic templating approach and highlights the high potential of this original strategy for the formation of nanostructured silica based materials which appears as a complementary strategy to conventional soft templating approaches.

  4. Perfluoroalkyl Acids (PFAAs) and Selected Precursors in the Baltic Sea Environment: Do Precursors Play a Role in Food Web Accumulation of PFAAs?

    Science.gov (United States)

    Gebbink, Wouter A; Bignert, Anders; Berger, Urs

    2016-06-21

    The present study examined the presence of perfluoroalkyl acids (PFAAs) and selected precursors in the Baltic Sea abiotic environment and guillemot food web, and investigated the relative importance of precursors in food web accumulation of PFAAs. Sediment, water, zooplankton, herring, sprat, and guillemot eggs were analyzed for perfluoroalkane sulfonic acids (PFSAs; C4,6,8,10) and perfluoroalkyl carboxylic acids (PFCAs; C6-15) along with six perfluoro-octane sulfonic acid (PFOS) precursors and 11 polyfluoroalkyl phosphoric acid diesters (diPAPs). FOSA, FOSAA and its methyl and ethyl derivatives (Me- and EtFOSAA), and 6:2/6:2 diPAP were detected in sediment and water. While FOSA and the three FOSAAs were detected in all biota, a total of nine diPAPs were only detected in zooplankton. Concentrations of PFOS precursors and diPAPs exceeded PFOS and PFCA concentrations, respectively, in zooplankton, but not in fish and guillemot eggs. Although PFOS precursors were present at all trophic levels, they appear to play a minor role in food web accumulation of PFOS based on PFOS precursor/PFOS ratios and PFOS and FOSA isomer patterns. The PFCA pattern in fish could not be explained by the intake pattern based on PFCAs and analyzed precursors, that is, diPAPs. Exposure to additional precursors might therefore be a dominant exposure pathway compared to direct PFCA exposure for fish.

  5. Trending analysis of precursor events

    International Nuclear Information System (INIS)

    Watanabe, Norio

    1998-01-01

    The Accident Sequence Precursor (ASP) Program of United States Nuclear Regulatory Commission (U.S.NRC) identifies and categorizes operational events at nuclear power plants in terms of the potential for core damage. The ASP analysis has been performed on yearly basis and the results have been published in the annual reports. This paper describes the trends in initiating events and dominant sequences for 459 precursors identified in the ASP Program during the 1969-94 period and also discusses a comparison with dominant sequences predicted in the past Probabilistic Risk Assessment (PRA) studies. These trends were examined for three time periods, 1969-81, 1984-87 and 1988-94. Although the different models had been used in the ASP analyses for these three periods, the distribution of precursors by dominant sequences show similar trends to each other. For example, the sequences involving loss of both main and auxiliary feedwater were identified in many PWR events and those involving loss of both high and low coolant injection were found in many BWR events. Also, it was found that these dominant sequences were comparable to those determined to be dominant in the predictions by the past PRAs. As well, a list of the 459 precursors identified are provided in Appendix, indicating initiating event types, unavailable systems, dominant sequences, conditional core damage probabilities, and so on. (author)

  6. Report on Fukushima Daiichi NPP precursor events

    International Nuclear Information System (INIS)

    2014-01-01

    The main questions to be answered by this report were: The Fukushima Daiichi NPP accident, could it have been prevented? If there is a next severe accident, may it be prevented? To answer the first question, the report addressed several aspects. First, the report investigated whether precursors to the Fukushima Daiichi NPP accident existed in the operating experience; second, the reasons why these precursors did not evolve into a severe accident. Third, whether lessons learned from these precursor events were adequately considered by member countries; and finally, if the operating experience feedback system needs to be improved, based on the previous analysis. To address the second question which is much more challenging, the report considered precursor events identified through a search and analysis of the IRS database and also precursors events based on risk significance. Both methods can point out areas where further work may be needed, even if it depends heavily on design and site-specific factors. From the operating experience side, more efforts are needed to ensure timely and full implementation of lessons learnt from precursor events. Concerning risk considerations, a combined use of risk precursors and operating experience may drive to effective changes to plants to reduce risk. The report also contains a short description and evaluation of selected precursors that are related to the course of the Fukushima Daiichi NPP accident. The report addresses the question whether operating experience feedback can be effectively used to identify plant vulnerabilities and minimize potential for severe core damage accidents. Based on several of the precursor events national or international in-depth evaluations were started. The vulnerability of NPPs due to external and internal flooding has clearly been addressed. In addition to the IRS based investigation, the WGRISK was asked to identify important precursor events based on risk significance. These precursors have

  7. Teor de clorofila e perfil de sais minerais de Chlorella vulgaris cultivada em solução hidropônica residual Chlorophyll content and minerals profile in the microalgae Chlorella vulgaris cultivated in hydroponic wastewater

    Directory of Open Access Journals (Sweden)

    Fabiano Cleber Bertoldi

    2008-02-01

    Full Text Available O cultivo de microalgas representa uma potencial fonte de biomassa rica em clorofila e sais minerais como: fósforo, ferro, manganês, cobre, zinco, magnésio e cálcio. Este experimento teve como objetivo avaliar a composição de minerais, bem como determinar o teor de clorofila a e b da microalga Chlorella vulgaris cultivada em solução hidropônica residual em três diferentes concentrações comparadas com um cultivo controle. Os resultados mostraram que os teores de clorofila a e b da microalga não apresentaram diferença significativa entre os cultivos. Com relação à composição dos sais minerais, a Chlorella cultivada na solução residual mais concentrada apresentou valores superiores quando comparada com a cultivada nos demais cultivos. Dessa forma, a biomassa da Chlorella vulgaris demonstrou ser uma potencial fonte de clorofila e de sais minerais, quando cultivada em solução hidropônica residual, possibilitando a utilização desse resíduo de forma sustentável.The microalgaes cultive represents a potential source of biomass rich in chlorophyll and minerals as: P, Fe, Mn, Cu, Zn, Mg and Ca. This research was aimed at evaluating the composition of minerals, as well as, determining the content of chlorophyll a and b from the microalgae Chlorella vulgaris cultivated in hydroponic wastewater in three different concentrations compared with the control cultive. The results showed that the contents of chlorophyll a and b of the microalgae did not show significant difference between the cultives. In relation to the composition of the minerals, the Chlorella cultivated in the most concentrated wastewater, showed higher values when compared with the one cultivated in the others cultures. In this manner, the Chlorella vulgaris biomass demonstrated to be a potential source of chlorophyll and minerals, when cultivated in hydroponic wastewater, allowing the use of this residue in a sustainable way.

  8. Biochemical Removal of HAP Precursors From Coal

    Energy Technology Data Exchange (ETDEWEB)

    Olson, G.; Tucker, L.; Richards, J.

    1997-07-01

    This project addresses DOE`s interest in advanced concepts for controlling emissions of air toxics from coal-fired utility boilers. We are determining the feasibility of developing a biochemical process for the precombustion removal of substantial percentages of 13 inorganic hazardous air pollutant (HAP) precursors from coal. These HAP precursors are Sb, As, Be, Cd, Cr, Cl, Co, F, Pb, Hg, Mn, Ni, and Se. Although rapid physical coal cleaning is done routinely in preparation plants, biochemical processes for removal of HAP precursors from coal potentially offer advantages of deeper cleaning, more specificity, and less coal loss. Compared to chemical processes for coal cleaning, biochemical processes potentially offer lower costs and milder process conditions. Pyrite oxidizing bacteria, most notably Thiobacillusferrooxidans, are being evaluated in this project for their ability to remove HAP precursors from U.S. coals.

  9. Biochemical Removal of HAP Precursors From Coal

    International Nuclear Information System (INIS)

    Olson, G.; Tucker, L.; Richards, J.

    1997-07-01

    This project addresses DOE's interest in advanced concepts for controlling emissions of air toxics from coal-fired utility boilers. We are determining the feasibility of developing a biochemical process for the precombustion removal of substantial percentages of 13 inorganic hazardous air pollutant (HAP) precursors from coal. These HAP precursors are Sb, As, Be, Cd, Cr, Cl, Co, F, Pb, Hg, Mn, Ni, and Se. Although rapid physical coal cleaning is done routinely in preparation plants, biochemical processes for removal of HAP precursors from coal potentially offer advantages of deeper cleaning, more specificity, and less coal loss. Compared to chemical processes for coal cleaning, biochemical processes potentially offer lower costs and milder process conditions. Pyrite oxidizing bacteria, most notably Thiobacillusferrooxidans, are being evaluated in this project for their ability to remove HAP precursors from U.S. coals

  10. SEARCH FOR PRECURSOR ERUPTIONS AMONG TYPE IIB SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Strotjohann, Nora L.; Ofek, Eran O.; Gal-Yam, Avishay; Yaron, Ofer [Benoziyo Center for Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel); Sullivan, Mark [School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ (United Kingdom); Kulkarni, Shrinivas R.; Cao, Yi [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Shaviv, Nir J. [School of Natural Sciences, Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ 08540 (United States); Fremling, Christoffer; Sollerman, Jesper [The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Kasliwal, Mansi M. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Nugent, Peter E. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Arcavi, Iair [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Goleta, CA 93111 (United States); Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Laher, Russ; Surace, Jason [Spitzer Science Center, California Institute of Technology, M/S 314-6, Pasadena, CA 91125 (United States)

    2015-10-01

    The progenitor stars of several Type IIb supernovae (SNe) show indications of extended hydrogen envelopes. These envelopes might be the outcome of luminous energetic pre-explosion events, so-called precursor eruptions. We use the Palomar Transient Factory (PTF) pre-explosion observations of a sample of 27 nearby SNe IIb to look for such precursors during the final years prior to the SN explosion. No precursors are found when combining the observations in 15-day bins, and we calculate the absolute-magnitude-dependent upper limit on the precursor rate. At the 90% confidence level, SNe IIb have on average <0.86 precursors as bright as an absolute R-band magnitude of −14 in the final 3.5 years before the explosion and <0.56 events over the final year. In contrast, precursors among SNe IIn have a ≳5 times higher rate. The kinetic energy required to unbind a low-mass stellar envelope is comparable to the radiated energy of a few-weeks-long precursor that would be detectable for the closest SNe in our sample. Therefore, mass ejections, if they are common in such SNe, are radiatively inefficient or have durations longer than months. Indeed, when using 60-day bins, a faint precursor candidate is detected prior to SN 2012cs (∼2% false-alarm probability). We also report the detection of the progenitor of SN 2011dh that does not show detectable variability over the final two years before the explosion. The suggested progenitor of SN 2012P is still present, and hence is likely a compact star cluster or an unrelated object.

  11. Distribuição espacial e lixiviação natural de sais em solos do Perímetro Irrigado Califórnia, em Sergipe

    Directory of Open Access Journals (Sweden)

    Ronaldo S. Resende

    Full Text Available RESUMO Em regiões áridas e semiáridas do planeta, a elevada demanda evaporativa e as características pedogenéticas dos solos, associadas a deficiências no sistema de drenagem de alguns perímetros irrigados, contribuem para um elevado potencial de salinização desses solos. Assim, constituíram objetivos deste estudo determinar o grau de salinização na área irrigada e avaliar o processo de acumulação de sais no período seco e o potencial de lixiviação destes pela água das chuvas no Perímetro Irrigado Califórnia, em Sergipe. Medidas da condutividade elétrica do extrato de saturação do solo (CEes, em dS m-1 a 25 ºC, foram efetuadas no início e final do período chuvoso dos anos de 2008 e 2009. A densidade amostral foi igualmente distribuída em toda área do Perímetro. Os dados foram submetidos à análise geoestatística e gerados mapas da distribuição espacial da CEes por meio do programa ArcGis®. Os valores médios da CEes obtidos revelaram que, apesar da prática de agricultura irrigada intensiva por longo período, o processo de acumulação de sais não foi significativo, tanto na camada superficial (0-0,20 m quanto em subsuperfície (0,20-0,40 m. Os valores médios da CEes em superfície variaram de 0,47 a 1,10 dS m-1, ficando abaixo de valores da salinidade limiar para a maioria das culturas anuais e perenes.

  12. Bioinspired magnetite synthesis via solid precursor phases

    NARCIS (Netherlands)

    Lenders, J.J.M.; Mirabello, G.; Sommerdijk, N.A.J.M.

    2016-01-01

    Living organisms often exploit solid but poorly ordered mineral phases as precursors in the biomineralization of their inorganic body parts. Generally speaking, such precursor-based approaches allow the organisms-without the need of high supersaturation levels-to accumulate significant quantities of

  13. Apuntes sobre esporotricosis

    OpenAIRE

    Londoño, Fabio

    2011-01-01

    Se hace una breve reseña histórica de las primeras comunicaciones sobre esporotricosis. Se destaca la amplia difusión de la enfermedad en nuestro país. 3. Se hace notar la no existencia de datos bibliográficos sobre formas extracutáneas. 4. Se llama la atención sobre la eficaz ayuda de la intradermo-reacción con esporotriquina en el diagnóstico de la enfermedad. 5- Se comunica un caso de esporotricosis verrugosa tratado con anfotericin B, con excelentes resultados

  14. Apuntes sobre esporotricosis

    Directory of Open Access Journals (Sweden)

    Fabio Londoño

    1960-01-01

    Full Text Available Se hace una breve reseña histórica de las primeras comunicaciones sobre esporotricosis. Se destaca la amplia difusión de la enfermedad en nuestro país. 3. Se hace notar la no existencia de datos bibliográficos sobre formas extracutáneas. 4. Se llama la atención sobre la eficaz ayuda de la intradermo-reacción con esporotriquina en el diagnóstico de la enfermedad. 5- Se comunica un caso de esporotricosis verrugosa tratado con anfotericin B, con excelentes resultados

  15. Probabilistic precursor analysis - an application of PSA

    International Nuclear Information System (INIS)

    Hari Prasad, M.; Gopika, V.; Sanyasi Rao, V.V.S.; Vaze, K.K.

    2011-01-01

    Incidents are inevitably part of the operational life of any complex industrial facility, and it is hard to predict how various contributing factors combine to cause the outcome. However, it should be possible to detect the existence of latent conditions that, together with the triggering failure(s), result in abnormal events. These incidents are called precursors. Precursor study, by definition, focuses on how a particular event might have adversely developed. This paper focuses on the events which can be analyzed to assess their potential to develop into core damage situation and looks into extending Probabilistic Safety Assessment techniques to precursor studies and explains the benefits through a typical case study. A preliminary probabilistic precursor analysis has been carried out for a typical NPP. The major advantages of this approach are the strong potential for augmenting event analysis which is currently carried out purely on deterministic basis. (author)

  16. Planar half-cell shaped precursor body

    DEFF Research Database (Denmark)

    2015-01-01

    The invention relates to a half-cell shaped precursor body of either anode type or cathode type, the half-cell shaped precursor body being prepared to be free sintered to form a sintered or pre-sintered half-cell being adapted to be stacked in a solid oxide fuel cell stack. The obtained half......-cell has an improved planar shape, which remains planar also after a sintering process and during temperature fluctuations....

  17. Rapid synthesis of macrocycles from diol precursors

    DEFF Research Database (Denmark)

    Wingstrand, Magnus; Madsen, Charlotte Marie; Clausen, Mads Hartvig

    2009-01-01

    A method for the formation of synthetic macrocycles with different ring sizes from diols is presented. Reacting a simple diol precursor with electrophilic reagents leads to a cyclic carbonate, sulfite or phosphate in a single step in 25-60% yield. Converting the cyclization precursor to a bis-ele...

  18. Precursors in photonic crystals - art. no. 618218

    NARCIS (Netherlands)

    Uitham, R.; Hoenders, B. J.; DeLaRue, RM; Viktorovitch, P; Lopez, C; Midrio, M

    2006-01-01

    We derive the Sommerfeld precursor and present the first calculations for the Brillouin precursor that result from the transmission of a pulse through a photonic crystal. The photonic crystal is modelled by a one-dimensional N-layer medium and the pulse is a generic electromagnetic plane wave packet

  19. Adenine nucleotide translocator transports haem precursors into mitochondria.

    Directory of Open Access Journals (Sweden)

    Motoki Azuma

    2008-08-01

    Full Text Available Haem is a prosthetic group for haem proteins, which play an essential role in oxygen transport, respiration, signal transduction, and detoxification. In haem biosynthesis, the haem precursor protoporphyrin IX (PP IX must be accumulated into the mitochondrial matrix across the inner membrane, but its mechanism is largely unclear. Here we show that adenine nucleotide translocator (ANT, the inner membrane transporter, contributes to haem biosynthesis by facilitating mitochondrial accumulation of its precursors. We identified that haem and PP IX specifically bind to ANT. Mitochondrial uptake of PP IX was inhibited by ADP, a known substrate of ANT. Conversely, ADP uptake into mitochondria was competitively inhibited by haem and its precursors, suggesting that haem-related porphyrins are accumulated into mitochondria via ANT. Furthermore, disruption of the ANT genes in yeast resulted in a reduction of haem biosynthesis by blocking the translocation of haem precursors into the matrix. Our results represent a new model that ANT plays a crucial role in haem biosynthesis by facilitating accumulation of its precursors into the mitochondrial matrix.

  20. Precursors of chicken flavor. II. Identification of key flavor precursors using sensory methods.

    Science.gov (United States)

    Aliani, Michel; Farmer, Linda J

    2005-08-10

    Sensory evaluation was used to identify flavor precursors that are critical for flavor development in cooked chicken. Among the potential flavor precursors studied (thiamin, inosine 5'-monophosphate, ribose, ribose-5-phosphate, glucose, and glucose-6-phosphate), ribose appears most important for chicken aroma. An elevated concentration (added or natural) of only 2-4-fold the natural concentration gives an increase in the selected aroma and flavor attributes of cooked chicken meat. Assessment of the volatile odor compounds by gas chromatography-odor assessment and gas chromatography-mass spectrometry showed that ribose increased odors described as "roasted" and "chicken" and that the changes in odor due to additional ribose are probably caused by elevated concentrations of compounds such as 2-furanmethanethiol, 2-methyl-3-furanthiol, and 3-methylthiopropanal.

  1. CHEMICAL VAPOUR DEPOSITION FROM A RADIATION-SENSITIVE PRECURSOR

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates in one aspect to a method of depositing a thin film on a substrate by chemical vapour deposition (CVD) from a radiation-sensitive precursor substance. The method comprises the steps of: (i) placing the substrate in a reaction chamber of a CVD system; (ii) heating...... heating pulse followed by an idle period; (iii) during at least one of the idle periods, providing a pressure pulse of precursor substance inside the reaction chamber by feeding at least one precursor substance to the reaction chamber so as to establish a reaction partial pressure for thin film deposition...... is formed. According to a further aspect, the invention relates to a chemical vapour deposition (CVD) system for depositing a thin film onto a substrate using precursor substances containing at least one radiation sensitive species....

  2. PROPIEDADES MECÁNICAS DE PELÍCULAS HÍBRIDAS (ORGÁNICO-INORGÁNICO SOBRE ACERO INOXIDABLE 304 Mechanical Properties of Hybrid Films (Organic-Inorganic on Stainless Steel 304

    Directory of Open Access Journals (Sweden)

    Jorge H. Bautista-Ruiz

    2011-12-01

    Full Text Available This article shows the creation of ceramic films of the SiO2-TiO2 Organic Polymer hybrid system from Tetraethyl-Orthosilicate (Si (OC2H54 and Titanium Tetrabutoxide (Ti(OBu4 synthesized through the sol-gel method in several volumetric concentrations of precursors. This hybrid system was deposited on AISI 304 stainless steel substrates through the dip-coating technique. Feasibility for obtaining hybrid and homogeneous coatings on this type of substrate and evaluating the surface properties was studies. For such a purpose, the coating microhardness and adhesion were studies. Additionally, the film surface was characterized through the SEM (Scanning Electron Microscopy. The study concluded that characteristics of films change in function of the volumetric amount of precursors used for creating films.Este trabajo muestra la conformación de películas cerámicas del sistema híbrido SiO2-TiO2-Polímero Orgánico, a partir de tetraetil-ortosilicato (Si (OC2H54, y tetra-butoxido de titanio (Ti(OBu4 y sintetizado por el método sol-gel en diferentes concentraciones volumétricas de los precursores. Este sistema híbrido se depositó sobre sustratos de acero inoxidable AISI 304 mediante la técnica de inmersión (dip-coating. Se estudió la viabilidad de obtener recubrimientos híbridos homogéneos sobre este tipo de sustrato y evaluar las propiedades superficiales. Para tal efecto, se estudió microdureza y adhesión del recubrimiento. Adicionalmente, se caracterizó la superficie de las películas por microscopía electrónica de barrido (MEB. Del estudio se concluye que las características de las películas cambian en función de la cantidad volumétrica de los precursores utilizados en la conformación de las mismas.

  3. Gifts reserved for age: a Lacanian study of comedy in Philip Roth’s Exit Ghost = Dons reservados para a idade madura: um estudo lacaniano sobre a comédia em O fantasma sai de cena (2007, de Philip Roth

    Directory of Open Access Journals (Sweden)

    James Milton Mellard

    2010-01-01

    Full Text Available The critical problem surrounding Philip Roth’s recent Exit Ghost (2007, the ninth and projected by the author as the final Zuckerman novel, is how it can function as comedy when one major character is dying of brain cancer and its protagonist is seventy-one years old, beginning to receive an elderly male’s gifts reserved for age –prostate cancer, prostate surgery, impotence, and incontinence – and, despite all, falls in love with a thirty-year-old married woman. A sequel to The Ghost Writer (1979, the first Zuckerman novel, whose character relations it repeats, Exit Ghost has comparatively less humor than its predecessor but there is humor enough. Moreover, and more important, it fits the genre of comedy because of the functions it gives to the classically traditional motifs of the phallus, castration, age versus youth, Eros and Thanatos, and the like. It is from a Lacanian critical perspective that it can be shown how the novel moves toward comedy’s conventional happy ending because of the duality of meanings attached to the matter of castration, the way in which Roth/Zuckerman displaces the object of desire from the young woman and finds it – enjoyment, jouissance – in the very process of writing itself.O grande problema para a crítica de O fantasma sai de cena, até agora o penúltimo romance de Philip Roth, concebido como o último envolvendo Nathan Zuckerman, é classificá-lo como comédia, e um de seus mais importantes personagens está morrendo de câncer no cérebro e o protagonista tem 71 anos e já está recebendo os dons reservados para a idade madura masculina, ou seja, câncer de próstata, cirurgia prostática, impotência, incontinência urinária e, apesar de tudo, apaixona-se por uma mulher casada, de 30 anos. Sendo uma continuação da série iniciada por The Ghost Writer (1979, o primeiro romance em que aparece o personagem Zuckerman, cujas relações com os demaispersonagens se repetem, O fantasma sai de cena

  4. Urban renewal based wind environment at pedestrian level in high-density and high-rise urban areas in Sai Ying Pun, Hong Kong

    Science.gov (United States)

    Yao, J. W.; Zheng, J. Y.; Zhao, Y.; Shao, Y. H.; Yuan, F.

    2017-11-01

    In high-density and high-rise urban areas, pedestrian level winds contribute to improve comfort, safety and diffusion of heat in urban areas. Outdoor wind study is extremely vital and a prerequisite in high-density cities considering that the immediate pedestrian level wind environment is fundamentally impacted by the presence of a series of high-rise buildings. In this paper, the research site of Sai Ying Pun in Hong Kong will be analysed in terms of geography, climate and urban morphology, while the surrounding natural ventilation has also been simulated by the wind tunnel experiment Computational Fluid Dynamics (CFD). It has found that, the existing problems in this district are the contradiction between planning control and commercial interests, which means some areas around tall buildings are not benefit to the residents because of the unhealthy wind environment. Therefore, some recommendation of urban renewal strategy has been provided.

  5. The proliferative human monocyte subpopulation contains osteoclast precursors

    Science.gov (United States)

    Lari, Roya; Kitchener, Peter D; Hamilton, John A

    2009-01-01

    Introduction Immediate precursors of bone-resorbing osteoclasts are cells of the monocyte/macrophage lineage. Particularly during clinical conditions showing bone loss, it would appear that osteoclast precursors are mobilized from bone marrow into the circulation prior to entering tissues undergoing such loss. The observed heterogeneity of peripheral blood monocytes has led to the notion that different monocyte subpopulations may have special or restricted functions, including as osteoclast precursors. Methods Human peripheral blood monocytes were sorted based upon their degree of proliferation and cultured in macrophage colony-stimulating factor (M-CSF or CSF-1) and receptor activator of nuclear factor-kappa-B ligand (RANKL). Results The monocyte subpopulation that is capable of proliferation gave rise to significantly more multinucleated, bone-resorbing osteoclasts than the bulk of the monocytes. Conclusions Human peripheral blood osteoclast precursors reside in the proliferative monocyte subpopulation. PMID:19222861

  6. Thermo-radiosensitivity of the granulocyte and macrophage precursor cells of mice. I I . - X- irradiation effects and influence of hyperthermia on the radiosensitivity; Termo-radiosensibilidad del precursor hematopoyetico que origina las series granulocitica y macrofaga de raton. II. - Efectos producidos por la radiacion X e influencia de la hipertermia sobre la radiosensibilidad celular

    Energy Technology Data Exchange (ETDEWEB)

    Bueren, J A; Nieto, M

    1983-07-01

    The effects of the X-irradiation on the viability of the granulocyte-macrophage precursors, has been determined by means of the agar diffusion chamber culture technique. The results show the high radiosensitivity of these cells, with survival parameter similar to those previously reported in the literature about different granulocyte-macrophage precursors. When a hyperthermic treatment is performed prior to the X-irradiation, a radiosensitization phenomenon is observed due to the synergism existent between hyperthermia and X rays on the lethality of the precursors. (Authors) 37 refs.

  7. Radiochemical Means of Investigating Delayed Neutron Precursors

    International Nuclear Information System (INIS)

    Marmol, P. del

    1968-01-01

    Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope separator techniques; it is concluded that the methods are complementary. (author)

  8. Radiochemical Means of Investigating Delayed Neutron Precursors

    International Nuclear Information System (INIS)

    Marmol, P. del

    1968-01-01

    Fast radiochemical methods used now for the determination of delayed neutron precursors are classified and reviewed: precipitations, solvent extractions, range experiments, milking, gas sweeping, isotopic and ion exchange, hot-atom reactions and diffusion loss. Advantages and limitations of irradiation systems with respect to fast separations are discussed: external beams which allow faster separations only have low neutron fluxes, internal beams which are mostly fit for gaseous reactions; and rabbits for solution irradiations. Future prospects of radiochemical procedures are presented; among these, studies should be mostly oriented towards gaseous reactions which offer possibilities of isolating very short-lived delayed neutron precursors. Chemical procedures for delayed neutron precursor detection are compared with mass spectrometric and isotope-separator techniques; it is concluded that the methods are complementary. (author)

  9. Thin HTSC films produced by a polymer metal precursor technique

    Science.gov (United States)

    Lampe, L. v.; Zygalsky, F.; Hinrichsen, G.

    In precursors the metal ions are combined with acid groups of polymethacrylic acid (PMAA), polyacrylic acid (PAA) or novolac. Compared to thermal degradation temperature of pure polymers those of precursors are low. Precursors films were patterned by UV lithography. Diffractometric investigations showed that the c-axis oriented epitaxial films of YBa 2Cu 3O x and Bi 2Sr 2CaCu 2O x originated from amorphous metal oxide films, which were received after thermal degradation of the precursor. Transition temperatures and current densities were determined by electric resistivity measurements.

  10. The EM Earthquake Precursor

    Science.gov (United States)

    Jones, K. B., II; Saxton, P. T.

    2013-12-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two

  11. Natural attenuation of NDMA precursors in an urban, wastewater-dominated wash.

    Science.gov (United States)

    Woods, Gwen C; Dickenson, Eric R V

    2016-02-01

    N-Nitrosodimethylamine (NDMA) is a disinfection by-product (DBP) that is potentially carcinogenic and has been found to occur in drinking water treatment systems impacted with treated wastewater. A major gap in NDMA research is an understanding of the persistence of wastewater-derived precursors within the natural environment. This research sought to fill this knowledge gap by surveying NDMA precursors across the length of a wastewater effluent-dominated wash. Significant precursor reduction (17%) was found to occur from introduction into the wash to a point 9 h downstream. This reduction translates into a half-life of roughly 32 h for bulk NDMA precursors. Further laboratory experiments examining rates of photolysis, biodegradation and loss to sediments, illustrated that both photolytic and biological degradation were effective removal mechanisms for NDMA precursors. Loss to sediments that were acquired from the wash did not appear to reduce NDMA precursors in the water column, although a control conducted with DI water provided evidence that significant NDMA precursors could be released from autoclaved sediments (suggesting that sorption does occur). Microbial experiments revealed that microbes associated with sediments were much more effective at degrading precursors than microbes within the water column. Overall, this study demonstrated that natural processes are capable of attenuating NDMA precursors relatively quickly within the environment, and that utilities might benefit from maximizing source water residency time in the environment, prior to introduction into treatment plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Characterization and classification or the first meteorite fall in Varre-Sai town, southeast Brazil, using X-ray microfluorescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Haimon D.L. [Universidade Federal do Rio de Janeiro (COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear; Assis, Joaquim T. de, E-mail: joaquim@iprj.uerj.b [Instituto Politecnico do Rio de Janeiro (IPRJ/UERJ), Nova Friburgo, RJ (Brazil); Valeriano, Claudio [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Geologia; Turbay, Caio [Universidade Federal do Espirito Santo (UFES), Alegre, ES (Brazil). Dept. de Geologia

    2011-07-01

    On the night of June 19th, 2010, a meteorite fell nearby the town of Varre-Sai, Rio de Janeiro state, southeast Brazil. A small part of it was found and taken for analysis. A meteorite analysis can give researchers a better understanding of the origins of the Universe. However, some of the most traditionalist methods of characterization and classification of meteorites are destructive. In this paper we present the results of a chemical analysis and classification of this particular meteorite using X-ray microfluorescence ({mu}XRF), a non-destructive technique that allows for a quick and easy elemental analysis within the range of micrometers. Both sides of the meteorite were measured, 35 points in total, using Artax, a state of the art {mu}XRF system developed by Bruker, at 50 kV tension and 700 {mu}A current. Quantitative analysis using direct comparison of counting rates method showed concentrations of iron and nickel together of roughly 7.86%. We found that it is possible to distinguish this meteorite from most of the categories as an ordinary L-type chondrite but a more thorough analysis might be necessary so as to obtain a more detailed classification. (author)

  13. Analysis of Precursor Properties of mixed Al/Alumel Cylindrical Wire Arrays*

    Science.gov (United States)

    Stafford, A.; Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Weller, M. E.; Shrestha, I.; Osborne, G. C.; Shlyaptseva, V. V.; Keim, S. F.; Coverdale, C. A.; Chuvatin, A. S.

    2012-10-01

    Previous studies of mid-Z (Cu and Ni) cylindrical wire arrays (CWAs) on Zebra have found precursors with high electron temperatures of >300 eV. However, past experiments with Al CWAs did not find the same high temperature precursors. New precursor experiments using mixed Al/Alumel (Ni 95%, Si 2%, and Al 2%) cylindrical wire arrays have been performed to understand how the properties of L-shell Ni precursor will change and whether Al precursor will be observed. Time gated spectra and pinholes are used to determine precursor plasma conditions for comparison with previous Alumel precursor experiments. A full diagnostic set which included more than ten different beam-lines was implemented. Future work in this direction is discussed. [4pt] *This work was supported by NNSA under DOE Cooperative Agreements DE-FC52-06NA27588, and in part by DE-FC52-06NA27586, and DE-FC52-06NA27616. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  14. Methods for forming particles from single source precursors

    Science.gov (United States)

    Fox, Robert V [Idaho Falls, ID; Rodriguez, Rene G [Pocatello, ID; Pak, Joshua [Pocatello, ID

    2011-08-23

    Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

  15. Efecto de la naturaleza del precursor sobre las caracteristicas de las nanoparticulas de SnO2 sintetizadas Effect of the precursor's nature on characteristics of synthesized SnO2 nanoparticles

    Directory of Open Access Journals (Sweden)

    Carlos E. Ararat-Ibarguen

    2007-01-01

    Full Text Available Tin oxide (SnO2 is widely used in industry as raw material for electronic devices, plating of different types of materials, for dyes and pigments, for electroplating, heterogeneous catalysis, etc. In this work SnO2 was obtained by a controlled precipitation method with special attention to the effects the tin precursor has on the microstructure of the final product. The most appropriate pH for obtaining SnO2 with the rutile structure as the main phase is 6.25 for SnCl2 and 6.40 for SnSO4. After heat treatment at 600 °C, particles of nanometric order (~10 - 30 nm approx were obtained. The characterization of the solid phase was made by X-ray diffraction (XRD, thermal analysis (DTA/TG, transmission electron microscopy (TEM and Fourier transformed infrared spectroscopy (FTIR.

  16. ARTIGOS PUBLICADOS EM PERIÓDICOS INTERNACIONAIS SOBRE CORE INFLATION NO PERÍODO DE 2000 A 2010

    Directory of Open Access Journals (Sweden)

    Ilse Maria Beuren

    2013-07-01

    Full Text Available O estudo objetiva ampliar o conhecimento sobre os artigos publicados em periódicos internacio-nais relativos ao tema core inflation. O interesse pelo tema decorre do fato dele ter atraído a aten-ção de pesquisadores e sido foco de debates acadêmicos. Pesquisa descritiva, com abordagem qualitativa, foi realizada em artigos de periódicos internacionais do Portal CAPES. Com base nos critérios de busca definidos, identificaram-se 108 artigos no período de 2000-2010. Desses, 72 foram desprezados na análise por terem sido publicados em periódicos sem avaliação do fa-tor de impacto. Outros 4 artigos foram descartados por constarem em 2 periódicos com fator de impacto inferior a 0,5. Os resultados da pesquisa mostram que o ano de 2004 teve a maior quan-tidade de publicações, com 7 artigos. A maioria dos artigos foi desenvolvida por um ou dois au-tores. A estratégia de pesquisa mais utilizada nos artigos para identificar e avaliar o core inflation foi a modelagem. O artigo de Gordon (2000 apresenta o maior número de citações na literatura sobre o tema, com 1.406 citações, intitulado Does the 'New Economy' measure up to the great In-ventions of the Past?. Ratifica-se assim a importância do autor, tido como o precursor da discus-são científica sobre core inflation.

  17. Use of one delayed-neutron precursor group in transient analysis

    International Nuclear Information System (INIS)

    Diamond, D.J.

    1983-01-01

    In most reactor dynamics calculations six groups of delayed-neutron precursors are usually accounted for. However, under certain circumstances it may be advantageous to simplify the calculation and utilize a single delayed-neutron group. The motivation for going to one precursor group is economy. For LWR transient codes that use point kinetics the equations are solved very rapidly and six precursor groups should always be used. However, codes with spatially dependent neutron kinetics are very long running and the use of one precursor group may save computer costs and not impair the accuracy of the results significantly. Furthermore, in some codes, the elimation of five presursor groups makes additional memory available which may be used to give a net increase in the accuracy of the calculations, e.g., by allowing for an increase in mesh density. In order to use one delayed neutron precursor group it is necessary to derive a single decay constant, 6 lambda-, which, along with the total (or one group) delayed neutron fraction β = Σ/sub i = 1/β/sub i/, will adequately describe the transeint precursor behavior. The present summary explains how a recommendation for lambda- was derived

  18. Functional Analysis of Precursors for Serious Problem Behavior and Related Intervention

    Science.gov (United States)

    Langdon, Nancy A.; Carr, Edward G.; Owen-DeSchryver, Jamie S.

    2008-01-01

    Precursor behaviors are innocuous behaviors that reliably precede the occurrence of problem behavior. Intervention efforts applied to precursors might prevent the occurrence of severe problem behavior. We examined the relationship between precursor behavior and problem behavior in three individuals with developmental disabilities. First, a…

  19. Geometrizing configurations. Heinrich Hertz and his mathematical precursors

    DEFF Research Database (Denmark)

    Lützen, Jesper

    1999-01-01

    A comparison between the methods used by Heinrich hertz and his mathematician precursors such as Liouville, Lipschitz and Darboux in order to apply differential geometry in mechanics......A comparison between the methods used by Heinrich hertz and his mathematician precursors such as Liouville, Lipschitz and Darboux in order to apply differential geometry in mechanics...

  20. Artigos Publicados em Periódicos Internacionais Sobre Core Inflation no Período de 2000 a 2010

    Directory of Open Access Journals (Sweden)

    Ilse Maria Beuren

    2013-07-01

    Full Text Available O estudo objetiva ampliar o conhecimento sobre os artigos publicados em periódicos internacionais relativos ao tema core inflation. O interesse pelo tema decorre do fato dele ter atraído a atenção de pesquisadores e sido foco de debates acadêmicos. Pesquisa descritiva, com abordagem qualitativa, foi realizada em artigos de periódicos internacionais do Portal CAPES. Com base nos critérios de busca definidos, identificaram-se 108 artigos no período de 2000-2010. Desses, 72 foram desprezados na análise por terem sido publicados em periódicos sem avaliação do fator de impacto. Outros 4 artigos foram descartados por constarem em 2 periódicos com fator de impacto inferior a 0,5. Os resultados da pesquisa mostram que o ano de 2004 teve a maior quantidade de publicações, com 7 artigos. A maioria dos artigos foi desenvolvida por um ou dois autores. A estratégia de pesquisa mais utilizada nos artigos para identificar e avaliar o core inflation foi a modelagem. O artigo de Gordon (2000 apresenta o maior número de citações na literatura sobre o tema, com 1.406 citações, intitulado Does the 'New Economy' measure up to the great Inventions of the Past?. Ratifica-se assim a importância do autor, tido como o precursor da discussão científica sobre core inflation.

  1. Influência de Íons de Potássio e Cálcio nos Géis de Carragenas Kappa e Iota

    Directory of Open Access Journals (Sweden)

    Valeriana Silveira Andrade

    2015-07-01

    Full Text Available No presente estudo avaliou-se a influência da concentração de diferentes sais (KCl, CaCl2.2H2O, K2SO4, e CaSO4.2H2O sobre as carragenas Kappa e Iota (polissacarídeos sulfatados utilizados principalmente na indústria alimentícia, de cosméticos e têxteis, como géis, estabilizantes, espessantes e emulsificantes em dispersões aquosas deionizadas, suas propriedades gelificantes, sinérese e pH. Para análise de textura foi utilizado o analisador de textura TAXT/2i Stable Micro Sytems. O método de penetração mostrou que em todas as provas, acima de certo limite, ocasionou-se impacto negativo sobre o sistema investigado. As parcelas de força de compressão para a k-carragena variaram consideravelmente, com resultados satisfatórios em relação à interação dos ions Ca2+ para os dois sais utilizados. Os melhores resultados de força de compressão em concentrações maiores foram obtidos com KCl. já utilizando-se o sal K2SO4 não houve significativas variações. Quanto a i-carragena, a pequena variação obtida, provalvelmente é decorrente de impurezas de k-carragena.

  2. Precursors to potential severe core damage accidents: 1995 A status report

    International Nuclear Information System (INIS)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.

    1997-04-01

    Ten operational events that affected 10 commercial light-water reactors during 1995 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by first computer-screening the 1995 licensee event reports from commercial light-water reactors to identify those events that could potentially be precursors. Candidate precursors were selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969-1981 and 1984-1994 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events

  3. Precursors to potential severe core damage accidents: 1995 A status report

    Energy Technology Data Exchange (ETDEWEB)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A. [and others

    1997-04-01

    Ten operational events that affected 10 commercial light-water reactors during 1995 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10{sup {minus}6}. These events were identified by first computer-screening the 1995 licensee event reports from commercial light-water reactors to identify those events that could potentially be precursors. Candidate precursors were selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969-1981 and 1984-1994 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events.

  4. Hydrokinetic simulations of nanoscopic precursor films in rough channels

    International Nuclear Information System (INIS)

    Chibbaro, S; Biferale, L; Binder, K; Milchev, A; Dimitrov, D; Diotallevi, F; Succi, S

    2009-01-01

    We report on simulations of capillary filling of highly wetting fluids in nanochannels with and without obstacles. We use atomistic (molecular dynamics) and hydrokinetic (lattice Boltzmann; LB) approaches which indicate clear evidence of the formation of thin precursor films, moving ahead of the main capillary front. The dynamics of the precursor films is found to obey a square-root law like that obeyed by the main capillary front, z 2 (t)∝t, although with a larger prefactor, which we find to take the same value for the different geometries (2D–3D) under inspection. The two methods show a quantitative agreement which indicates that the formation and propagation of thin precursors can be handled at a mesoscopic/hydrokinetic level. This can be considered as a validation of the LB method and opens the possibility of using hydrokinetic methods to explore space–time scales and complex geometries of direct experimental relevance. Then, the LB approach is used to study the fluid behaviour in a nanochannel when the precursor film encounters a square obstacle. A complete parametric analysis is performed which suggests that thin-film precursors may have an important influence on the efficiency of nanochannel-coating strategies

  5. Development of an accident sequence precursor methodology and its application to significant accident precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Seung Hyun; Park, Sung Hyun; Jae, Moo Sung [Dept. of of Nuclear Engineering, Hanyang University, Seoul (Korea, Republic of)

    2017-03-15

    The systematic management of plant risk is crucial for enhancing the safety of nuclear power plants and for designing new nuclear power plants. Accident sequence precursor (ASP) analysis may be able to provide risk significance of operational experience by using probabilistic risk assessment to evaluate an operational event quantitatively in terms of its impact on core damage. In this study, an ASP methodology for two operation mode, full power and low power/shutdown operation, has been developed and applied to significant accident precursors that may occur during the operation of nuclear power plants. Two operational events, loss of feedwater and steam generator tube rupture, are identified as ASPs. Therefore, the ASP methodology developed in this study may contribute to identifying plant risk significance as well as to enhancing the safety of nuclear power plants by applying this methodology systematically.

  6. Efecto de la ingesta de cereales enriquecidos con triptófano sobre el sueño, melatonina, serotonina, cortisol y estado antioxidante en personas mayores

    OpenAIRE

    Matito Celaya, Sergio

    2015-01-01

    Teniendo en cuenta el concepto de Crononutrición y la secreción de melatonina, serotonina, cortisol durante el día y la noche, nuestro objetivo ha sido analizar como el consumo de cereales enriquecidos con triptófano, precursor de Serotonina y Melatonina, puede ayudar a la reestructuración del ciclo sueño / vigilia, como actúa sobre la secreción de Cortisol matutino y como la Melatonina ayuda a la excreción de radicales libres en orina por su capacidad antioxidante. Para objetivar como afec...

  7. Digital signage sobre IP

    OpenAIRE

    Casademont Filella, Albert

    2012-01-01

    Projecte que versa sobre el disseny i la implementació d'un sistema de Digital Signage (Cartelleria Digital) sobre IP, creant un gestor que permeti controlar de forma remota tot un conjunt de petits dispositius connectats a pantalles que emeten continguts multimèdia com vídeos, imatges, feeds rss...

  8. Methods of making copper selenium precursor compositions with a targeted copper selenide content and precursor compositions and thin films resulting therefrom

    Science.gov (United States)

    Curtis, Calvin J [Lakewood, CO; Miedaner, Alexander [Boulder, CO; van Hest, Marinus Franciscus Antonius Maria; Ginley, David S [Evergreen, CO; Leisch, Jennifer [Denver, CO; Taylor, Matthew [West Simsbury, CT; Stanbery, Billy J [Austin, TX

    2011-09-20

    Precursor compositions containing copper and selenium suitable for deposition on a substrate to form thin films suitable for semi-conductor applications. Methods of forming the precursor compositions using primary amine solvents and methods of forming the thin films wherein the selection of temperature and duration of heating controls the formation of a targeted species of copper selenide.

  9. The Innate Lymphoid Cell Precursor.

    Science.gov (United States)

    Ishizuka, Isabel E; Constantinides, Michael G; Gudjonson, Herman; Bendelac, Albert

    2016-05-20

    The discovery of tissue-resident innate lymphoid cell populations effecting different forms of type 1, 2, and 3 immunity; tissue repair; and immune regulation has transformed our understanding of mucosal immunity and allergy. The emerging complexity of these populations along with compounding issues of redundancy and plasticity raise intriguing questions about their precise lineage relationship. Here we review advances in mapping the emergence of these lineages from early lymphoid precursors. We discuss the identification of a common innate lymphoid cell precursor characterized by transient expression of the transcription factor PLZF, and the lineage relationships of innate lymphoid cells with conventional natural killer cells and lymphoid tissue inducer cells. We also review the rapidly growing understanding of the network of transcription factors that direct the development of these lineages.

  10. The electromagnetic Brillouin precursor in one-dimensional photonic crystals

    NARCIS (Netherlands)

    Uitham, R.; Hoenders, B. J.

    2008-01-01

    We have calculated the electromagnetic Brillouin precursor that arises in a one-dimensional photonic crystal that consists of two homogeneous slabs which each have a single electron resonance. This forerunner is compared with the Brillouin precursor that arises in a homogeneous double-electron

  11. The presence of modifiable residues in the core peptide part of precursor nisin is not crucial for precursor nisin interactions with NisB- and NisC.

    Directory of Open Access Journals (Sweden)

    Rustem Khusainov

    Full Text Available Precursor nisin is a model posttranslationally modified precursor lantibiotic that can be structurally divided into a leader peptide sequence and a modifiable core peptide part. The nisin core peptide clearly plays an important role in the precursor nisin-nisin modification enzymes interactions, since it has previously been shown that the construct containing only the nisin leader sequence is not sufficient to pull-down the nisin modification enzymes NisB and NisC. Serines and threonines in the core peptide part are the residues that NisB specifically dehydrates, and cysteines are the residues that NisC stereospecifically couples to the dehydrated amino acids. Here, we demonstrate that increasing the number of negatively charged residues in the core peptide part of precursor nisin, which are absent in wild-type nisin, does not abolish binding of precursor nisin to the modification enzymes NisB and NisC, but dramatically decreases the antimicrobial potency of these nisin mutants. An unnatural precursor nisin variant lacking all serines and threonines in the core peptide part and an unnatural precursor nisin variant lacking all cysteines in the core peptide part still bind the nisin modification enzymes NisB and NisC, suggesting that these residues are not essential for direct interactions with the nisin modification enzymes NisB and NisC. These results are important for lantibiotic engineering studies.

  12. An optimized In–CuGa metallic precursors for chalcopyrite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jun-feng, E-mail: junfeng.han@cnrs-imn.fr [Institut des Matériaux Jean Rouxel (IMN), Université de Nantes, UMR CNRS 6502, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Department of Physics, Peking University, Beijing 100871 (China); Liao, Cheng [Department of Physics, Peking University, Beijing 100871 (China); Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan Province 601207 (China); Jiang, Tao; Xie, Hua-mu; Zhao, Kui [Department of Physics, Peking University, Beijing 100871 (China); Besland, M.-P. [Institut des Matériaux Jean Rouxel (IMN), Université de Nantes, UMR CNRS 6502, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France)

    2013-10-31

    We report a study of CuGa–In metallic precursors for chalcopyrite thin film. CuGa and In thin films were prepared by DC sputtering at room temperature. Due to low melting point of indium, the sputtering power on indium target was optimized. Then, CuGa and In multilayers were annealed at low temperature. At 120 °C, the annealing treatment could enhance diffusion and alloying of CuGa and In layers; however, at 160 °C, it caused a cohesion and crystalline of indium from the alloy which consequently formed irregular nodules on the film surface. The precursors were selenized to form copper indium gallium selenide (CIGS) thin films. The morphological and structural properties were investigated by scanning electron microscopy, X-ray diffraction and Raman spectra. The relationships between metallic precursors and CIGS films were discussed in the paper. A smooth precursor layer was the key factor to obtain a homogeneous and compact CIGS film. - Highlights: • An optimized sputtered indium film • An optimized alloying process of metallic precursor • An observation of nodules forming on the indium film and precursor surface • An observation of cauliflower structure in copper indium gallium selenide film • The relationship between precursor and CIGS film surface morphology.

  13. Cryopreservation of GABAergic Neuronal Precursors for Cell-Based Therapy.

    Directory of Open Access Journals (Sweden)

    Daniel Rodríguez-Martínez

    Full Text Available Cryopreservation protocols are essential for stem cells storage in order to apply them in the clinic. Here we describe a new standardized cryopreservation protocol for GABAergic neural precursors derived from the medial glanglionic eminence (MGE, a promising source of GABAergic neuronal progenitors for cell therapy against interneuron-related pathologies. We used 10% Me2SO as cryoprotectant and assessed the effects of cell culture amplification and cellular organization, as in toto explants, neurospheres, or individualized cells, on post-thaw cell viability and retrieval. We confirmed that in toto cryopreservation of MGE explants is an optimal preservation system to keep intact the interneuron precursor properties for cell transplantation, together with a high cell viability (>80% and yield (>70%. Post-thaw proliferation and self-renewal of the cryopreserved precursors were tested in vitro. In addition, their migration capacity, acquisition of mature neuronal morphology, and potency to differentiate into multiple interneuron subtypes were also confirmed in vivo after transplantation. The results show that the cryopreserved precursor features remained intact and were similar to those immediately transplanted after their dissection from the MGE. We hope this protocol will facilitate the generation of biobanks to obtain a permanent and reliable source of GABAergic precursors for clinical application in cell-based therapies against interneuronopathies.

  14. Manganite perovskite ceramics, their precursors and methods for forming

    Science.gov (United States)

    Payne, David Alan; Clothier, Brent Allen

    2015-03-10

    Disclosed are a variety of ceramics having the formula Ln.sub.1-xM.sub.xMnO.sub.3, where 0.Itoreq.x.Itoreq.1 and where Ln is La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or Y; M is Ca, Sr, Ba, Cd, or Pb; manganite precursors for preparing the ceramics; a method for preparing the precursors; and a method for transforming the precursors into uniform, defect-free ceramics having magnetoresistance properties. The manganite precursors contain a sol and are derived from the metal alkoxides: Ln(OR).sub.3, M(OR).sub.2 and Mn(OR).sub.2, where R is C.sub.2 to C.sub.6 alkyl or C.sub.3 to C.sub.9 alkoxyalkyl, or C.sub.6 to C.sub.9 aryl. The preferred ceramics are films prepared by a spin coating method and are particularly suited for incorporation into a device such as an integrated circuit device.

  15. Whole-cell fungal transformation of precursors into dyes

    Directory of Open Access Journals (Sweden)

    Jarosz-Wilkołazka Anna

    2010-07-01

    Full Text Available Abstract Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25. Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other

  16. Inferencias sobre Grafos

    OpenAIRE

    Sira M. Allende; Carlos N. Bouza

    2002-01-01

    El estudio de un juego puede ser modelado asumiendo que solo algunas partidas son observadas. Entonces el árbol del juego debe ser estimado utilizando información muestral. Similarmente ocurre al obtener información sobre el comportamiento de las decisiones tomadas por individuos muestreados sobre un árbol de decisión teórico. Al considerar una medida de probabilidad que caracterice el comportamiento de redes aleatorias se puede obtener un estimado del árbol asociado. Este problema es el anal...

  17. Desempenho de novilhos suplementados com sais proteinados em pastagem nativa Performance of steers supplemented with protein salts on native pastures

    Directory of Open Access Journals (Sweden)

    Marcelo Knorr

    2005-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da suplementação com sais proteinados sobre o desempenho de novilhos em pastagem nativa diferida, no Rio Grande do Sul, Brasil. Os suplementos de sal proteinado avaliados foram: com uréia, com amiréia, com amiréia mais levedura e sal mineral. O experimento teve duração de 118 dias e foram utilizadas 8 parcelas com área de 7,5 ha, cada uma com 8 novilhos, de peso médio 264 kg, com idade de 18 meses, em delineamento completamente casualizado. A pastagem apresentou valores médios de 6,8% de proteína bruta, 73,3% de fibra em detergente neutro, e 42,5% de digestibilidade in vitro da matéria orgânica, sem que fossem detectadas diferenças significativas entre tratamentos. O ganho médio diário (0,287 kg dos animais suplementados com o sal proteinado com amiréia e levedura, foi superior ao apresentado pelos animais que consumiram sal mineralizado (0,019 kg mas não houve diferenças entre uréia (0,159 kg e amiréia (0,124 kg. O consumo diário dos suplementos proteinados (0,400 kg foi superior ao consumo do suplemento mineral (0,038 kg. A adição de levedura ativa, ao sal proteinado formulado com amiréia, melhora o desempenho de novilhos em pastagem nativa diferida.The objective of this work was to evaluate the effect of protein salts supplementation on performance of beef steers grazing differed native pasture in Rio Grande do Sul State, Brazil. Protein salts were supplemented with: urea, starea, starea plus yeast, and mineral salt. The experiment was conducted during 118 days, and utilized 8 paddocks with 7.5 ha each one, with 8 steers averaging 264 kg and 18 months old, in a completely randomized design. Average composition of pasture was 6.8% of crude protein, 73.3% of neutral detergent fiber, and 42.5% in vitro organic matter digestibility; significative differences weren't detected among treatments. Average daily weight gain of animals fed protein salt with starea plus yeast (0

  18. Biochemical Removal of HAP Precursors from Coal

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Gregory J

    1997-05-12

    Column biooxidation tests with Kentucky coal confirmed results of earlier shake flask tests showing significant removal from the coal of arsenic, selenium, cobalt, manganese, nickel and cadmium. Rates of pyrite biooxidation in Kentucky coal were only slightly more than half the rates found previously for Indiana and Pittsburgh coals. Removal of pyrite from Pittsburgh coal by ferric ion oxidation slows markedly as ferrous ions accumulate in solution, requiring maintenance of high redox potentials in processes designed for removal of pyrite and hazardous air pollutant (HAP) precursors by circulation of ferric solutions through coal. The pyrite oxidation rates obtained in these tests were used by Unifield Engineering to support the conceptual designs for alternative pyrite and HAP precursor bioleaching processes for the phase 2 pilot plant. Thermophilic microorganisms were tested to determine if mercury could be mobilized from coal under elevated growth temperatures. There was no evidence for mercury removal from coal under these conditions. However, the activity of the organisms may have liberated mercury physically. It is also possible that the organisms dissolved mercury and it readsorbed to the clay preferentially. Both of these possibilities are undergoing further testing. The Idaho National Engineering and Environmental Laboratory's (INEEL) slurry column reactor was operated and several batches of feed coal, product coal, waste solids and leach solutions were submitted to LBL for HAP precursor analysis. Results to date indicate significant removal of mercury, arsenic and other HAP precursors in the combined physical-biological process.

  19. Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales cultivadas

    Directory of Open Access Journals (Sweden)

    Lázara Castillo

    1996-06-01

    Full Text Available En este trabajo se describe la acción del factor de crecimiento epidérmico (FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glías. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema de cultivo empleado, la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y, posteriormente, fue tratada con 20 ng/mL del FCE en un medio libre de suero. La eliminación del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Al parecer, la población de células sobrevivientes estaba integrada, en su mayoría, por precursores celulares teniendo en cuenta su capacidad proliferativa. La acción del FCE sobre las células se manifestó en un aumento del número de células debido fundamentalmente a un estímulo de la proliferación de los precursores neuronales y astrocitos. Este efecto estuvo acompañado por una reducción de la diferenciación morfológica neuronal cuando se comparó con los cultivos controles. En los cultivos, a los 16 días, la detección de la actividad específica de la colina acetiltrasferasa evidenció la diferenciación de una subpoblación neuronal colinérgica, las cuales respondieron al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de la enzima.

  20. Non-invasive method for in vivo detection of chlorophyll precursors

    DEFF Research Database (Denmark)

    Kristiansen, Kim Anker; Khrouchtchova, Anastassia; Stenbæk, Anne

    2009-01-01

    Traditionally chlorophyll (Chl) and Chl precursors have been studied in vitro or in leaf tissue at low temperature. These methods are destructive and make it impossible to work with the same individual plant later on. In this paper we present a method for in vivo detection of Chl and its precursors...... is compared to current methods. Furthermore, we report on optimization of the spectral scanning method with the aim to minimize the excitation light-evoked photo-conversion of the chlorophyll precursors....

  1. Unconsumed precursors and couplers after formation of oxidative hair dyes

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Søsted, Heidi; Johansen, Jeanne Duus

    2006-01-01

    Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene......-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative...... hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus...

  2. Capability of cation exchange technology to remove proven N-nitrosodimethylamine precursors.

    Science.gov (United States)

    Li, Shixiang; Zhang, Xulan; Bei, Er; Yue, Huihui; Lin, Pengfei; Wang, Jun; Zhang, Xiaojian; Chen, Chao

    2017-08-01

    N-nitrosodimethylamine (NDMA) precursors consist of a positively charged dimethylamine group and a non-polar moiety, which inspired us to develop a targeted cation exchange technology to remove NDMA precursors. In this study, we tested the removal of two representative NDMA precursors, dimethylamine (DMA) and ranitidine (RNTD), by strong acidic cation exchange resin. The results showed that pH greatly affected the exchange efficiency, with high removal (DMA>78% and RNTD>94%) observed at pHMg 2+ >RNTD + >K + >DMA + >NH 4 + >Na + . The partition coefficient of DMA + to Na + was 1.41±0.26, while that of RNTD + to Na + was 12.1±1.9. The pseudo second-order equation fitted the cation exchange kinetics well. Bivalent inorganic cations such as Ca 2+ were found to have a notable effect on NA precursor removal in softening column test. Besides DMA and RNTD, cation exchange process also worked well for removing other 7 model NDMA precursors. Overall, NDMA precursor removal can be an added benefit of making use of cation exchange water softening processes. Copyright © 2017. Published by Elsevier B.V.

  3. Sobre software libre

    OpenAIRE

    Matellán Olivera, Vicente; González Barahona, Jesús; Heras Quirós, Pedro de las; Robles Martínez, Gregorio

    2004-01-01

    220 p. "Sobre software libre" reune casi una treintena de ensayos sobre temas de candente actualidad relacionados con el software libre (del cual Linux es su ex- ponente más conocido). Los ensayos que el lector encontrará están divididos en bloques temáticos que van desde la propiedad intelectual o las cuestiones económicas y sociales de este modelo hasta su uso en la educación y las administraciones publicas, pasando por alguno que repasa la historia del software libre en l...

  4. Cellular Kinetics of Perivascular MSC Precursors

    Directory of Open Access Journals (Sweden)

    William C. W. Chen

    2013-01-01

    Full Text Available Mesenchymal stem/stromal cells (MSCs and MSC-like multipotent stem/progenitor cells have been widely investigated for regenerative medicine and deemed promising in clinical applications. In order to further improve MSC-based stem cell therapeutics, it is important to understand the cellular kinetics and functional roles of MSCs in the dynamic regenerative processes. However, due to the heterogeneous nature of typical MSC cultures, their native identity and anatomical localization in the body have remained unclear, making it difficult to decipher the existence of distinct cell subsets within the MSC entity. Recent studies have shown that several blood-vessel-derived precursor cell populations, purified by flow cytometry from multiple human organs, give rise to bona fide MSCs, suggesting that the vasculature serves as a systemic reservoir of MSC-like stem/progenitor cells. Using individually purified MSC-like precursor cell subsets, we and other researchers have been able to investigate the differential phenotypes and regenerative capacities of these contributing cellular constituents in the MSC pool. In this review, we will discuss the identification and characterization of perivascular MSC precursors, including pericytes and adventitial cells, and focus on their cellular kinetics: cell adhesion, migration, engraftment, homing, and intercellular cross-talk during tissue repair and regeneration.

  5. Associations between musical abilities and precursors of reading in preschool aged children.

    Science.gov (United States)

    Degé, Franziska; Kubicek, Claudia; Schwarzer, Gudrun

    2015-01-01

    The association between music and language, in particular, the overlap in their processing results in the possibility to use one domain for the enhancement of the other. Especially in the preschool years music may be a valuable tool to train language abilities (e.g., precursors of reading). Therefore, detailed knowledge about associations between musical abilities and precursors of reading can be of great use for designing future music intervention studies that target language-related abilities. Hence, the present study investigated the association between music perception as well as music production and precursors of reading. Thereby, not only phonological awareness, the mostly studied precursor of reading, was investigated, but also other precursors were examined. We assessed musical abilities (production and perception) and precursors of reading (phonological awareness, working memory, and rapid retrieval from long-term memory) in 55 preschoolers (27 boys). Fluid intelligence was measured and controlled in the analyses. Results showed that phonological awareness, working memory, and rapid retrieval from long-term memory were related to music perception as well as to music production. Our data suggest that several precursors of reading were associated with music perception as well as music production.

  6. Associations between musical abilities and precursors of reading in preschool aged children

    Directory of Open Access Journals (Sweden)

    Franziska eDegé

    2015-08-01

    Full Text Available The association between music and language, in particular, the overlap in their processing results in the possibility to use one domain for the enhancement of the other. Especially in the preschool years music may be a valuable tool to train language abilities (e.g., precursors of reading. Therefore, detailed knowledge about associations between musical abilities and precursors of reading can be of great use for designing future music intervention studies that target language-related abilities. Hence, the present study investigated the association between music perception as well as music production and precursors of reading. Thereby, not only phonological awareness, the mostly studied precursor of reading, was investigated, but also other precursors were examined. We assessed musical abilities (production and perception and precursors of reading (phonological awareness, working memory, and rapid retrieval from long-term memory in 55 preschoolers (27 boys. Fluid intelligence was measured and controlled in the analyses. Results showed that phonological awareness, working memory, and rapid retrieval from long-term memory were related to music perception as well as to music production. Our data suggest that several precursors of reading were associated with music perception as well as music production.

  7. Precursor polymer compositions comprising polybenzimidazole

    Science.gov (United States)

    Klaehn, John R.; Peterson, Eric S.; Orme, Christopher J.

    2015-07-14

    Stable, high performance polymer compositions including polybenzimidazole (PBI) and a melamine-formaldehyde polymer, such as methylated, poly(melamine-co-formaldehyde), for forming structures such as films, fibers and bulky structures. The polymer compositions may be formed by combining polybenzimidazole with the melamine-formaldehyde polymer to form a precursor. The polybenzimidazole may be reacted and/or intertwined with the melamine-formaldehyde polymer to form the polymer composition. For example, a stable, free-standing film having a thickness of, for example, between about 5 .mu.m and about 30 .mu.m may be formed from the polymer composition. Such films may be used as gas separation membranes and may be submerged into water for extended periods without crazing and cracking. The polymer composition may also be used as a coating on substrates, such as metal and ceramics, or may be used for spinning fibers. Precursors for forming such polymer compositions are also disclosed.

  8. Tributos sobre a folha ou sobre o faturamento? Efeitos quantitativos para o Brasil

    Directory of Open Access Journals (Sweden)

    Tiago V Cavalcanti

    2008-09-01

    Full Text Available Este artigo estuda os impactos alocativos e de bem-estar de uma reforma tributária que substitui os impostos sobre a folha de salários por outro que incide sobre a receita. Para isso, desenvolve-se um modelo neoclássico de crescimento econômico com impostos sobre a receita e sobre a folha de salários. As simulações com parâmetros da economia brasileira mostram que tal reforma tributária tem um efeito negativo no bem-estar, no estoque de capital de longo prazo e consequentemente no produto per capita de longo prazo. Contudo, o emprego aumenta.This paper studies the impacts of a tax reform which substitutes taxes on labor income by taxes on total revenue. In order to accomplish that, we construct and solve a general equilibrium neoclassical growth model with taxes on labor income and total revenue. The numerical simulations with Brazilian parameters show that such tax reforms would negatively affect welfare, the capital stock, and consequently per capita output. However, employment would increase. Such effects are quantitatively important.

  9. Ionospheric precursors for crustal earthquakes in Italy

    Directory of Open Access Journals (Sweden)

    L. Perrone

    2010-04-01

    Full Text Available Crustal earthquakes with magnitude 6.0>M≥5.5 observed in Italy for the period 1979–2009 including the last one at L'Aquila on 6 April 2009 were considered to check if the earlier obtained relationships for ionospheric precursors for strong Japanese earthquakes are valid for the Italian moderate earthquakes. The ionospheric precursors are based on the observed variations of the sporadic E-layer parameters (h'Es, fbEs and foF2 at the ionospheric station Rome. Empirical dependencies for the seismo-ionospheric disturbances relating the earthquake magnitude and the epicenter distance are obtained and they have been shown to be similar to those obtained earlier for Japanese earthquakes. The dependences indicate the process of spreading the disturbance from the epicenter towards periphery during the earthquake preparation process. Large lead times for the precursor occurrence (up to 34 days for M=5.8–5.9 tells about a prolong preparation period. A possibility of using the obtained relationships for the earthquakes prediction is discussed.

  10. Aroma Precursors in Grapes and Wine: Flavor Release during Wine Production and Consumption.

    Science.gov (United States)

    Parker, Mango; Capone, Dimitra L; Francis, I Leigh; Herderich, Markus J

    2018-03-14

    Pioneering investigations into precursors of fruity and floral flavors established the importance of terpenoid and C 13 -norisoprenoid glycosides to the flavor of aromatic wines. Nowadays flavor precursors in grapes and wine are known to be structurally diverse, encompassing glycosides, amino acid conjugates, odorless volatiles, hydroxycinnamic acids, and many others. Flavor precursors mainly originate in the grape berry but also from oak or other materials involved in winemaking. Flavors are released from precursors during crushing and subsequent production steps by enzymatic and nonenzymatic transformations, via microbial glycosidases, esterases, C-S lyases, and decarboxylases, and through acid-catalyzed hydrolysis and chemical rearrangements. Flavors can also be liberated from glycosides and amino acid conjugates by oral microbiota. Hence, it is increasingly likely that flavor precursors contribute to retronasal aroma formation through in-mouth release during consumption, prompting a shift in focus from identifying aroma precursors in grapes to understanding aroma precursors present in bottled wine.

  11. Evaluación y conducta recomendada en presencia de precursores vítreorretinianos del desprendimiento de retina

    Directory of Open Access Journals (Sweden)

    Ceija Molina Cisneros

    Full Text Available Los cambios y las variaciones anatómicas vítreorretinianas predisponen al desprendimiento de retina regmatógeno, por lo que su conocimiento es de vital importancia para el tratamiento adecuado de los pacientes. Por ello se decidió realizar una revisión acerca de los elementos más importantes al respecto, con el objetivo de actualizar los conocimientos existentes sobre el tema. Estos precursores comprenden tres entidades que, por su fisiopatología, pueden estar presentes en la historia natural de esta afección: Desprendimiento de vítreo posterior, degeneraciones periféricas y desgarro de retina (sintomáticos y asintomáticos. Además, algunas situaciones de riesgo como la cirugía de catarata, la capsulotomía posterior con YAG-láser, los traumatismos y la miopía alta pueden favorecer también al desprendimiento de retina. Estos precursores, por lo general, se hacen más evidentes después de los 40 años, sin predilección por sexo o características raciales y están muy relacionadas con cambios vítreos o su licuefacción. El conocimiento básico y actualizado de estas entidades, así como de los factores de riesgo asociados al desprendimiento de retina es importante para el adecuado manejo y el control de las complicaciones. En la revisión se describen con claridad los pilares fundamentales para el diagnóstico y tratamiento de este tipo de situaciones clínicas.

  12. [The role of endothelial cells and endothelial precursor cells in angiogenesis].

    Science.gov (United States)

    Poreba, Małgorzata; Usnarska-Zubkiewicz, Lidia; Kuliczkowski, Kazimierz

    2006-01-01

    Endothelium plays a key role in maintenance of vascular homeostasis in human organism. According to new data endothelial cells and hematopoietic cells have a common precursor in prenatal life--a hemangioblast, which explains the fact of sharing the same determinants on the surface of both type of cells. Circulating endothelial precursors were identified in adults and this suggests that hemangioblasts may be present not only during embriogenesis. In some clinical situations the increased numbers of endothelial cells and endothelial precursors were noted, and especially in patients with neoplastic diseases, which is probably the result of increased angiogenesis. Endothelial precursors are thought to be the promice for therapeutic purposes in future--to increase local angiogenesis.

  13. The fate of wastewater-derived NDMA precursors in the aquatic environment.

    Science.gov (United States)

    Pehlivanoglu-Mantas, Elif; Sedlak, David L

    2006-03-01

    To assess the stability of precursors of the chloramine disinfection byproduct N-nitrosodimethylamine (NDMA) under conditions expected in effluent-dominated surface waters, effluent samples from four municipal wastewater treatment plants were subjected to chlorination and chloramination followed by incubation in the presence of inocula derived from activated sludge. Samples subjected to free chlorine disinfection showed lower initial concentrations of NDMA precursors than those that were not chlorinated or were disinfected with pre-formed chloramines. For chloraminated and control (unchlorinated) treatments, the concentration of NDMA precursors decreased by an average of 24% over the 30-day incubation in samples from three of the four facilities. At the fourth facility, where samples were collected on three different days, NDMA precursor concentrations decreased by approximately 80% in one sample and decreased by less than 20% in the other two samples. In contrast to the low reactivity of the NDMA precursors, NDMA disappeared within 30 days under the conditions employed in these experiments. These results and measurements made in an effluent-dominated river suggest that although NDMA may be removed after wastewater effluent is discharged, wastewater-derived NDMA precursors could persist long enough to form significant concentrations of NDMA in drinking water treatment plants that use water originating from sources that are subjected to wastewater effluent discharges.

  14. Four residues of propeptide are essential for precursor folding of nattokinase.

    Science.gov (United States)

    Jia, Yan; Cao, Xinhua; Deng, Yu; Bao, Wei; Tang, Changyan; Ding, Hanjing; Zheng, Zhongliang; Zou, Guolin

    2014-11-01

    Subtilisin propeptide functions as an intramolecular chaperone that guides precursor folding. Nattokinase, a member of subtilisin family, is synthesized as a precursor consisting of a signal peptide, a propeptide, and a subtilisin domain, and the mechanism of its folding remains to be understood. In this study, the essential residues of nattokinase propeptide which contribute to precursor folding were determined. Deletion analysis showed that the conserved regions in propeptide were important for precursor folding. Single-site and multi-site mutagenesis studies confirmed the role of Tyr10, Gly13, Gly34, and Gly35. During stage (i) and (ii) of precursor folding, Tyr10 and Gly13 would form the part of interface with subtilisin domain. While Gly34 and Gly35 connected with an α-helix that would stabilize the structure of propeptide. The quadruple Ala mutation, Y10A/G13A/G34A/G35A, resulted in a loss of the chaperone function for the propeptide. This work showed the essential residues of propeptide for precursor folding via secondary structure and kinetic parameter analyses. © The Author 2014. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

  15. nanoparticles synthesized by citrate precursor m

    African Journals Online (AJOL)

    user

    (M=Co, Cu) nanoparticles synthesized by citrate precursor method ... The structural characterization was carried out using an X-ray Diffractometer (Rikagu Miniflex, Japan) ..... His current area of interest includes magnetic nanomaterials.

  16. Investigación educativa reciente sobre México

    OpenAIRE

    Núñez-DelaPeña, Francisco J.; Mejía-Arauz, Rebeca

    1985-01-01

    Se presenta una muestra de la investigación educativa sobre México: 22 disertaciones doctorales aceptadas en universidades norteamericanas entre 1982 y 1984. Dos estudios conciernen a la teoría del capital humano; cinco tratan diversos aspectos relacionados con la administración educativa; uno es sobre la televisión; otro sobre las habilidades fonéticas de los niños; uno más es sobre profesionalización de los médicos; cuatro tocan aspectos de política educativa; tres tratan sobre los maestros...

  17. Precursor incident program at EDF

    International Nuclear Information System (INIS)

    Fourest, B.; Maliverney, B.; Rozenholc, M.; Piovesan, C.

    1998-01-01

    The precursor program was started by EDF in 1994, after an investigation of the US NRC's Accident Sequence Precursor Program. Since then, reported operational events identified as Safety Outstanding Events have been analyzed whenever possible using probabilistic methods based on PSAs. Analysis provides an estimate of the remaining protection against core damage at the time the incident occurred. Measuring the incidents' severity enables to detect incidents important regarding safety. Moreover, the most efficient feedback actions can be derived from the main accident sequences identified through the analysis. Therefore, incident probabilistic analysis provides a way to assess priorities in terms of treatment and resource allocation, and so, to implement countermeasures preventing further occurrence and development of the most significant incidents. As some incidents cannot be analyzed using this method, probabilistic analysis can only be one among the methods used to assess the nuclear power plants' safety level. Nevertheless, it provides an interesting complement to classical methods of deterministic studies. (author)

  18. GH mediates exercise-dependent activation of SVZ neural precursor cells in aged mice.

    Directory of Open Access Journals (Sweden)

    Daniel G Blackmore

    Full Text Available Here we demonstrate, both in vivo and in vitro, that growth hormone (GH mediates precursor cell activation in the subventricular zone (SVZ of the aged (12-month-old brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation.

  19. GH Mediates Exercise-Dependent Activation of SVZ Neural Precursor Cells in Aged Mice

    Science.gov (United States)

    Blackmore, Daniel G.; Vukovic, Jana; Waters, Michael J.; Bartlett, Perry F.

    2012-01-01

    Here we demonstrate, both in vivo and in vitro, that growth hormone (GH) mediates precursor cell activation in the subventricular zone (SVZ) of the aged (12-month-old) brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation. PMID:23209615

  20. Coercivities of hot-deformed magnets processed from amorphous and nanocrystalline precursors

    International Nuclear Information System (INIS)

    Tang, Xin; Sepehri-Amin, H.; Ohkubo, T.; Hioki, K.; Hattori, A.; Hono, K.

    2017-01-01

    Hot-deformed magnets have been processed from amorphous and nanocrystalline precursors and their hard magnetic properties and microstructures have been investigated in order to explore the optimum process route. The hot-deformed magnets processed from an amorphous precursor exhibited the coercivity of 1.40 T that is higher than that processed from nanocrystalline powder, ∼1.28 T. The average grain size was larger in the magnets processed from amorphous precursor. Detailed microstructure analyses by aberration corrected scanning transmission electron microscopy revealed that the Nd + Pr concentrations in the intergranular phases were higher in the hot-deformed magnet processed from the amorphous precursor, which is considered to lead to the enhanced coercivity due to a stronger pinning force against magnetic domain wall motion.

  1. Increased KPI containing amyloid precursor protein in experimental autoimmune encephalomyelitis brains.

    Science.gov (United States)

    Beilin, Orit; Karussis, Dimitrios M; Korczyn, Amos D; Gurwitz, David; Aronovich, Ramona; Mizrachi-Kol, Rachel; Chapman, Joab

    2007-04-16

    Amyloid precursor protein can be translated from three alternatively spliced mRNAs. We measured levels of amyloid precursor protein isoforms containing the Kunitz protease inhibitor domain (KPIAPP), and amyloid precursor protein without the Kunitz protease inhibitor domain (KPIAPP) in brain homogenates of acute experimental autoimmune encephalomyelitis mice. At the preclinical phase of the disease, both KPIAPP and KPIAPP levels were significantly higher in homogenates from brains of autoimmune encephalomyelitis mice, whereas at the acute phase of the disease only KPIAPP remained significantly elevated compared with controls. At the recovery phase, no differences were observed between the groups. The early and isoform-specific elevation of KPIAPP in autoimmune encephalomyelitis mice suggests a possible role for amyloid precursor protein in the immune response mediating the disease.

  2. Identification of an indigo precursor from leaves of Isatis tinctoria (Woad).

    Science.gov (United States)

    Maugard, T; Enaud, E; Choisy, P; Legoy, M D

    2001-11-01

    Indole is presumably a product of indole-3-glycerol phosphate catabolism in Isatis tinctoria. It is oxidized into indoxyl and stored in young leaves as indigo precursor. Further oxidation and dimerization of indoxyl produces indigoid pigments. In this work, we describe an HPLC method dedicated to the identification and quantification of indigoid pigments (indigo, indirubin, isoindigo and isoindirubin) and indigo precursors produced in I. tinctoria (Woad). This work, carried out with two cultivars of I. tinctoria, has confirmed that the quantity of indigo precursors is dependent on the species and the harvest period. In addition we have shown for the first time that young leaves of I. tinctoria, harvested in June contained a new indigo precursor in addition to isatan B (indoxyl-5-ketogluconate) and indican (indoxyl-beta-D-glucoside). We suggest the name "isatan C" for this new indigo precursor in I. tinctoria. Its chemical characteristics point to an dioxindole ester with PM of 395. We have shown that isatan C reacts with isatan B increasing the red pigment production.

  3. Application of precursor methodology in initiating frequency estimates

    International Nuclear Information System (INIS)

    Kohut, P.; Fitzpatrick, R.G.

    1991-01-01

    The precursor methodology developed in recent years provides a consistent technique to identify important accident sequence precursors. It relies on operational events (extracting information from actual experience) and infers core damage scenarios based on expected safety system responses. The ranking or categorization of each precursor is determined by considering the full spectrum of potential core damage sequences. The methodology estimates the frequency of severe core damage based on the approach suggested by Apostolakis and Mosleh, which may lead to a potential overestimation of the severe-accident sequence frequency due to the inherent dependencies between the safety systems and the initiating events. The methodology is an encompassing attempt to incorporate most of the operating information available from nuclear power plants and is an attractive tool from the point of view of risk management. In this paper, a further extension of this methodology is discussed with regard to the treatment of initiating frequency of the accident sequences

  4. Accident sequence precursor events with age-related contributors

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, G.A.; Kohn, W.E.

    1995-12-31

    The Accident Sequence Precursor (ASP) Program at ORNL analyzed about 14.000 Licensee Event Reports (LERs) filed by US nuclear power plants 1987--1993. There were 193 events identified as precursors to potential severe core accident sequences. These are reported in G/CR-4674. Volumes 7 through 20. Under the NRC Nuclear Plant Aging Research program, the authors evaluated these events to determine the extent to which component aging played a role. Events were selected that involved age-related equipment degradation that initiated an event or contributed to an event sequence. For the 7-year period, ORNL identified 36 events that involved aging degradation as a contributor to an ASP event. Except for 1992, the percentage of age-related events within the total number of ASP events over the 7-year period ({approximately}19%) appears fairly consistent up to 1991. No correlation between plant ape and number of precursor events was found. A summary list of the age-related events is presented in the report.

  5. Controlled Growth of ZnSe Nanocrystals by Tuning Reactivity and Amount of Zinc Precursor

    Directory of Open Access Journals (Sweden)

    Lai-Jun Zhang

    2013-01-01

    Full Text Available Zinc selenide (ZnSe nanocrystals were synthesized via a phosphine-free route using the highly reactive alkylamine-H2Se complex as selenium precursor and zinc precursors with different reactivity. The reactivity of zinc precursor was tuned by using three kinds of zinc carboxylates with different alkyl chain lengths, including zinc acetate, zinc nonanoate, and zinc stearate. The effect of the reactivity and the amount of zinc precursor on nucleation and growth of ZnSe nanocrystals were investigated by ultraviolet-visible absorption and photoluminescence spectra. Result indicates that the growth and optical property of the resulting ZnSe nanocrystals are strongly dependent on the alkyl chain length and the amount of the zinc carboxylates and both shorter alkyl chain length, and more amount of zinc carboxylate will lead to faster growth of ZnSe nanocrystals. This allows that the controlled growth and excellent optical property of high-quality ZnSe nanocrystals can be achieved by combining the different reactivity and the used amount of zinc precursor, such as by using stoichiometric and reactive Zn precursor and Se precursor or by using larger amount of more unreactive Zn precursor relative to the highly reactive alkylamine-H2Se complex precursor.

  6. Nonlinear magnetohydrodynamics of edge localized mode precursors

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Z. B., E-mail: guozhipku@gmail.com [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing (China); WCI Center for Fusion Theory, NFRI, Gwahangno 113, Yusung-gu, Daejeon 305-333 (Korea, Republic of); Wang, Lu [SEEE, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang, X. G. [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing (China)

    2015-02-15

    A possible origin of edge-localized-mode (ELM) precursors based on nonlinear ideal peeling-ballooning mode is reported. Via nonlinear variational principle, a nonlinear evolution equation of the radial displacement is derived and solved, analytically. Besides an explosive growth in the initial nonlinear phase, it is found that the local displacement evolves into an oscillating state in the developed nonlinear phase. The nonlinear frequency of the ELM precursors scales as ω{sub pre}∼x{sup 1/3}ξ{sup ^}{sub ψ,in}{sup 2/3}n, with x position in radial direction, ξ{sup ^}{sub ψ,in} strength of initial perturbation, and n toroidal mode number.

  7. Synthesis of labelled ecdysone precursors

    International Nuclear Information System (INIS)

    Haag, T.; Hetru, C.; Nakatani, Y.; Luu, B.; Meister, M.; Pichat, L.; Audinot, M.

    1985-01-01

    High specific activity tritiated 3β,14α-dihydroxy-5β-cholest-7-en-6-one, has been prepared using a precursor which permits rapid and easy labelling. This compound is converted to ecdysone under in vitro conditions by insect prothoracic glands, a well known site of ecdysone biosynthesis. (author)

  8. BEBIDA DE SOJA (GLYCINE MAX E ACEROLA (MALPIGHIA PUNICIFOLIA ENRIQUECIDA COM CÁLCIO

    Directory of Open Access Journals (Sweden)

    Elaine Cristina de Souza LIMA

    2012-12-01

    Full Text Available Na atualidade, as indústrias alimentícias vêm buscando novas formulações de produtos, devido ao aumento da demanda do consumidor por alimentos funcionais. A acerola e a soja são consideradas alimentos funcionais, no entanto, a soja apresenta teores limitantes de cálcio. O objetivo deste estudo foi avaliar o efeito da adição de diferentes sais de cálcio sobre as propriedades sensoriais de bebida formulada com adição de soja e acerola. Amostras dessa bebida natural (sem adição de cálcio e enriquecidas com quatro diferentes sais de cálcio - lactato de cálcio, carbonato de cálcio, gluconato de cálcio e fosfato tricálcio foram analisadas sensorialmente por 50 provadores, segundo escala hedônica estruturada de 7 pontos. A bebida enriquecida com melhor qualidade sensorial foi caracterizada físicoquímica e microbiologicamente. Dentre as bebidas de soja e acerola enriquecidas com sais de cálcio a que se destacou em termos de sabor global foi aquela enriquecida com lactato de cálcio. O teor de cálcio encontrado em 200 mL dessa bebida na forma pasteurizada foi capaz de suprir em torno de 38% da ingestão diária recomendável para adultos constituindo, assim, uma bebida funcional à base de soja, com alto valor nutritivo e boa qualidade sensorial.

  9. Análisis sobre la factibilidad de implementar un producto de derivados sobre gas natural en Colombia

    OpenAIRE

    Dowd Aguirre, Jessica Alexandra; Tirado Naranjo, Lina María

    2012-01-01

    El objetivo de este trabajo es realizar un análisis sobre la factibilidad de implementar un producto de derivados sobre gas natural en Colombia dado el desarrollo del sector y la importancia de este hidrocarburo como fuente alternativa de generación eléctrica. 73 p. Contenido parcial: Situación actual del mercado de gas natural colombiano -- Expectativas del mercado de gas natural colombiano -- Mercados de derivados sobre gas natural en Europa y Estados Unidos -- Mercado de gas natural ...

  10. Precursors to potential severe core damage accidents: 1996. A status report. Volume 25

    International Nuclear Information System (INIS)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Muhlheim, M.D.; Dolan, B.W.; Minarick, J.W.

    1997-12-01

    This report describes the 14 operational events in 1996 that affected 13 commercial light-water reactors and that are considered to be precursors to potential severe core damage accidents. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by first computer-screening the 1996 licensee event reports from commercial light-water reactors to identify those events that could potentially be precursors. Candidate precursors were selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1995 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events

  11. Precursors to potential severe core damage accidents: 1997 - A status report. Volume 26

    International Nuclear Information System (INIS)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Muhlheim, M.D.; Dolan, B.W.; Minarick, J.W.

    1998-11-01

    This report describes the five operational events in 1997 that affected five commercial light-water reactors (LWRs) and that are considered to be precursors to potential severe core damage accidents. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by first computer-screening the 1997 licensee event reports from commercial LWRs to identify those events that could be precursors. Candidate precursors were selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1996 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events

  12. Thin film solar cells by selenization sulfurization using diethyl selenium as a selenium precursor

    Science.gov (United States)

    Dhere, Neelkanth G.; Kadam, Ankur A.

    2009-12-15

    A method of forming a CIGSS absorber layer includes the steps of providing a metal precursor, and selenizing the metal precursor using diethyl selenium to form a selenized metal precursor layer (CIGSS absorber layer). A high efficiency solar cell includes a CIGSS absorber layer formed by a process including selenizing a metal precursor using diethyl selenium to form the CIGSS absorber layer.

  13. Do glycine-extended hormone precursors have clinical significance?

    DEFF Research Database (Denmark)

    Rehfeld, Jens Frederik

    2014-01-01

    Half of the known peptide hormones are C-terminally amidated. Subsequent biogenesis studies have shown that the immediate precursor is a glycine-extended peptide. The clinical interest in glycine-extended hormones began in 1994, when it was suggested that glycine-extended gastrin stimulated cancer...... and clinical effects of glycine-extended precursors for most other amidated hormones than gastrin and cholecystokinin (CCK). The idea of glycine-extended peptides as independent messengers was interesting. But clinical science has to move ahead from ideas that cannot be supported at key points after decades...

  14. Inferencias sobre Grafos

    Directory of Open Access Journals (Sweden)

    Sira M. Allende

    2002-05-01

    Full Text Available El estudio de un juego puede ser modelado asumiendo que solo algunas partidas son observadas. Entonces el árbol del juego debe ser estimado utilizando información muestral. Similarmente ocurre al obtener información sobre el comportamiento de las decisiones tomadas por individuos muestreados sobre un árbol de decisión teórico. Al considerar una medida de probabilidad que caracterice el comportamiento de redes aleatorias se puede obtener un estimado del árbol asociado. Este problema es el analizado en este trabajo. Algunos resultados experimentales obtenidos usando Recocido Simulado ilustran el procedimiento. Su papel en el estudio de modelos económicos y de mercadeo es discutido.

  15. Caracterización y cuantificación de la influencia de la música como agente físico sobre el comportamiento de células madre neurales embrionarias en cultivo

    OpenAIRE

    Navarro Fernández, Neysa

    2011-01-01

    Diferentes estudios científicos sugieren que la música podría ejercer una influencia directa sobre el comportamiento de células del SNC pero pocos clarifican este dato. Éste estudio surge con la intención establecer una relación directa y causal entre un fenómeno físico como es la música y el comportamiento de células del SNC. Para ello desarrollamos un modelo de cultivo in vitro de precursores neuroepiteliales de cerebro embrionario de ratón como modelo simple, altamente sensible a ...

  16. Conocimientos sobre incontinencia urinaria en pacientes hospitalizados

    Directory of Open Access Journals (Sweden)

    Otto Guillen Lopez

    2003-10-01

    Full Text Available Objetivo: Determinar el nivel de conocimientos sobre incontinencia urinaria (IU en pacientes hospitalizados. Material y métodos: Estudio transversal, descriptivo; se entrevistó una muestra por saturación de 325 pacientes hospitalizados de 30 años a más del Hospital Nacional Cayetano Heredia (HNCH, Lima - Perú, utilizando un cuestionario de conocimientos sobre incontinencia, considerándose como adecuado conocimiento cuando había más de 50% de aciertos en él. Resultados: Solamente 35.7% tuvieron conocimiento adecuado sobre IU. Hasta 90% conocía acerca del éxito del tratamiento y posibilidad de curación de los pacientes incontinentes. Sin embargo, 75% consideraron erróneamente que la IU era consecuencia inevitable del envejecimiento, mientras menos de 50% de pacientes conocía el papel de ciertos medicamentos y ejercicios en la IU. Conclusiones: Se demostró un pobre conocimiento general sobre la IU, siendo necesaria una intervención de los profesionales de la salud en la educación de la población, sobre todo hospitalizada y con factores predisponentes para desarrollar IU, para así poder modificar las ideas erróneas que existen sobre el tema. (Rev Med Hered 2003; 14: 186-194.

  17. Fluid Mechanics of Lean Blowout Precursors in Gas Turbine Combustors

    Directory of Open Access Journals (Sweden)

    T. M. Muruganandam

    2012-03-01

    Full Text Available Understanding of lean blowout (LBO phenomenon, along with the sensing and control strategies could enable the gas turbine combustor designers to design combustors with wider operability regimes. Sensing of precursor events (temporary extinction-reignition events based on chemiluminescence emissions from the combustor, assessing the proximity to LBO and using that data for control of LBO has already been achieved. This work describes the fluid mechanic details of the precursor dynamics and the blowout process based on detailed analysis of near blowout flame behavior, using simultaneous chemiluminescence and droplet scatter observations. The droplet scatter method represents the regions of cold reactants and thus help track unburnt mixtures. During a precursor event, it was observed that the flow pattern changes significantly with a large region of unburnt mixture in the combustor, which subsequently vanishes when a double/single helical vortex structure brings back the hot products back to the inlet of the combustor. This helical pattern is shown to be the characteristic of the next stable mode of flame in the longer combustor, stabilized by double helical vortex breakdown (VBD mode. It is proposed that random heat release fluctuations near blowout causes VBD based stabilization to shift VBD modes, causing the observed precursor dynamics in the combustor. A complete description of the evolution of flame near the blowout limit is presented. The description is consistent with all the earlier observations by the authors about precursor and blowout events.

  18. The biosynthesis and processing of high molecular weight precursors of soybean glycinin subunits.

    Science.gov (United States)

    Barton, K A; Thompson, J F; Madison, J T; Rosenthal, R; Jarvis, N P; Beachy, R N

    1982-06-10

    The predominant storage protein of soybean seed, glycinin, is composed of two heterogeneous classes of related subunits, the acidics (Mr approximately 38,000) and the basics (Mr approximately 22,000). Immunoreaction of polypeptides translated in vitro from isolated seed mRNA using antibodies prepared against either purified acidic or basic subunit groups precipitated precursor polypeptides of Mr = 60,000 to Mr = 63,000. High pressure liquid chromatography fingerprinting of trypsin-generated fragments from in vitro synthesized precursors showed fragments specific to both acidic and basic subunits. No mature acidic or basic subunits were detected in vitro translation reactions by either immunoprecipitation or high pressure liquid chromatography fingerprinting. Pulse-labeling of cotyledons growing in culture with [3H]glycine showed rapid accumulation of label in glycinin precursors of Mr = 59,000 to Mr = 62,000. Although in vivo synthesized precursors had slightly greater electrophoretic mobility than in vitro synthesized precursors, little label initially appeared in mature glycinin subunits. After several hours of continued cotyledon growth in absence of label, precursors were processed and label accumulated in both acidic and basic subunit groups. Recombinant plasmids were prepared by reverse transcription of soybean seed mRNA, and clones which encode glycinin precursors were identified by heteroduplex-hybridization of translatable messages. Northern blot analysis of seed mRNA shows the mRNA-encoding glycinin precursors to migrate at Mr = 0.71 X 10(6) on agarose gels, corresponding to approximately 2050 nucleotides. This is sufficiently large to encode a polypeptide consisting of both a glycinin acidic and basic subunit.

  19. Metabolic Precursors to Amphetamine and Methamphetamine.

    Science.gov (United States)

    Cody, J D

    1993-12-01

    Analysis and interpretation of amphetamine results is a challenging process made difficult by a number of factors. One of the complications comes from determination of the origin of amphetamine or methamphetamine in a sample. Given the relatively rare occasions that either of these two drugs are prescribed, legal prescription of one of these drugs is seldom a reason for positive findings. A number of other precursor compounds are metabolized by the body to amphetamine or methamphetamine, many of which could be used for legitimate reasons. Fourteen different metabolic precursors of amphetamine or methamphetamine are included in this review. They are amphetaminil, benzphetamine, clobenzorex, deprenyl, dimethylamphetamine, ethylamphetamine, famprofazone, fencamine, fenethylline, fenproporex, furfenorex, mefenorex, mesocarb, and prenylamine. Medical use, metabolism, analysis, and interpretation are described to afford sufficient information to evaluate the possible involvement of these drugs in positive amphetamine or methamphetamine results. Copyright © 1993 Central Police University.

  20. Comparison exercise of probabilistic precursor analysis

    International Nuclear Information System (INIS)

    Fauchille, V.; Babst, S.

    2004-01-01

    From 2000 up to 2003, a comparison exercise concerning accident precursor programs was performed by IRSN, GRS, and NUPEC (Japan). The objective of this exercise was to compare the methodologies used to quantify conditional core damage probability related to incidents which can be considered as accident precursors. This exercise provided interesting results concerning the interpretation of such events. Generally, the participants identified similar scenarios of potential degradation. However, for several dominant sequences, differences in the results were noticed. The differences can be attributed to variations in the plant design, the strategy of management and in the methodological approach. For many reasons, comparison of human reliability analysis was difficult and perhaps another exercise in the future could provide more information about this subject. On the other hand, interesting outcomes have been obtained from the quantification of both common cause failures and potential common cause failures. (orig.)

  1. A methodology for analyzing precursors to earthquake-initiated and fire-initiated accident sequences

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Lambert, H.E.; Apostolakis, G.

    1998-04-01

    This report covers work to develop a methodology for analyzing precursors to both earthquake-initiated and fire-initiated accidents at commercial nuclear power plants. Currently, the U.S. Nuclear Regulatory Commission sponsors a large ongoing project, the Accident Sequence Precursor project, to analyze the safety significance of other types of accident precursors, such as those arising from internally-initiated transients and pipe breaks, but earthquakes and fires are not within the current scope. The results of this project are that: (1) an overall step-by-step methodology has been developed for precursors to both fire-initiated and seismic-initiated potential accidents; (2) some stylized case-study examples are provided to demonstrate how the fully-developed methodology works in practice, and (3) a generic seismic-fragility date base for equipment is provided for use in seismic-precursors analyses. 44 refs., 23 figs., 16 tabs

  2. Precursors to potential severe core damage accidents: 1992, A status report

    International Nuclear Information System (INIS)

    Cox, D.F.; Cletcher, J.W.; Copinger, D.A.; Cross-Dial, A.E.; Morris, R.H.; Vanden Heuvel, L.N.; Dolan, B.W.; Jansen, J.M.; Minarick, J.W.; Lau, W.; Salyer, W.D.

    1993-12-01

    Twenty-seven operational events with conditional probabilities of subsequent severe core damage of 1.0 x 10E-06 or higher occurring at commercial light-water reactors during 1992 are considered to be precursors to potential core damage. These are described along with associated significance estimates, categorization, and subsequent analyses. The report discusses (1) the general rationale for this study, (2) the selection and documentation of events as precursors, (3) the estimation and use of conditional probabilities of subsequent severe core damage to rank precursor events, and (4) the plant models used in the analysis process

  3. Solution precursor plasma deposition of nanostructured ZnO coatings

    International Nuclear Information System (INIS)

    Tummala, Raghavender; Guduru, Ramesh K.; Mohanty, Pravansu S.

    2011-01-01

    Highlights: → The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. → It is highly capable of developing tailorable nanostructures. → This technique can be employed to spray the coatings on any kind of substrates including polymers. → The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance (∼65-80%) and reflectivity (∼65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 mΩ cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  4. Solution precursor plasma deposition of nanostructured ZnO coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tummala, Raghavender [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Guduru, Ramesh K., E-mail: rkguduru@umich.edu [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Mohanty, Pravansu S. [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States)

    2011-08-15

    Highlights: {yields} The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. {yields} It is highly capable of developing tailorable nanostructures. {yields} This technique can be employed to spray the coatings on any kind of substrates including polymers. {yields} The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance ({approx}65-80%) and reflectivity ({approx}65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 m{Omega} cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  5. Survey of perfluoroalkyl acids (PFAAs) and their precursors present in Japanese consumer products.

    Science.gov (United States)

    Ye, Feng; Zushi, Yasuyuki; Masunaga, Shigeki

    2015-05-01

    Perfluoroalkyl acids (PFAAs) and their precursors have been used in various consumer products. However, limited information regarding their occurrence and concentration levels in products is available. In this study, we investigated 18 PFAAs and 14 PFAA precursors in various categories of consumer products purchased in Japan. Relatively high total concentrations of PFAAs and their precursors were found in sprays for fabrics and textiles (car wash/coating products (precursor of perfluorooctane sulfonic acid (PFOS), N-methyl perfluorooctane sulfonamidoethanol (MeFOSE) was detected in a higher frequency (8%) and in greater concentrations (precursors in consumer products is required. Furthermore, the amount of PFAAs emitted from consumer products may be underestimated if the occurrence of PFAA precursors is not considered. In addition to PFAA precursors, long chain perfluoroalkyl carboxylic acids (PFCAs) (carbon chain length⩾7) were also detected in greater concentrations than short chain PFCAs (⩽6). This result suggests that consumer products are one of the important sources of long-chain PFCAs in the environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Non radioactive precursor import into chloroplasts

    International Nuclear Information System (INIS)

    Lombardo, V.A.; Ottado, J.

    2003-01-01

    Full text: Eukaryotic cells have a subcellular organization based on organelles. Protein transport to these organelles is quantitatively important because the majority of cellular proteins are codified in nuclear genes and then delivered to their final destination. Most of the chloroplast proteins are translated on cytoplasmic ribosomes as larger precursors with an amino terminal transit peptide that is necessary and sufficient to direct the precursor to the chloroplast. Once inside the organelle the transit peptide is cleaved and the mature protein adopts its folded form. In this work we developed a system for the expression and purification of the pea ferredoxin-NADP + reductase precursor (preFNR) for its import into chloroplasts in non radioactive conditions. We constructed a preFNR fused in its carboxy terminus to a 6 histidines peptide (preFNR-6xHis) that allows its identification using a commercial specific antibody. The construction was expressed, purified, processed and precipitated, rendering a soluble and active preFNR-6xHis that was used in binding and import into chloroplasts experiments. The reisolated chloroplasts were analyzed by SDS-PAGE, electro-blotting and revealed by immuno-detection using either colorimetric or chemiluminescent reactive. We performed also import experiments labeling preFNR and preFNR-6xHis with radioactive methionine as controls. We conclude that preFNR-6xHis is bound and imported into chloroplasts as the wild type preFNR and that both colorimetric or chemiluminescent detection methods are useful to avoid the manipulation of radioactive material. (author)

  7. Electron heating, magnetic field amplification, and cosmic-ray precursor length at supernova remnant shocks

    Energy Technology Data Exchange (ETDEWEB)

    Laming, J. Martin [Space Science Division, Naval Research Laboratory, Code 7684, Washington, DC 20375 (United States); Hwang, Una [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Ghavamian, Parviz [Department of Physics, Astronomy and Geosciences, Towson University, Towson, MD 21252 (United States); Rakowski, Cara, E-mail: laming@nrl.navy.mil, E-mail: Una.Hwang-1@nasa.gov, E-mail: pghavamian@towson.edu

    2014-07-20

    We investigate the observability, by direct and indirect means, of a shock precursor arising from magnetic field amplification by cosmic rays. We estimate the depth of such a precursor under conditions of nonresonant amplification, which can provide magnetic field strengths comparable to those inferred for supernova remnants. Magnetic field generation occurs as the streaming cosmic rays induce a plasma return current, and it may be quenched by either nonresonant or resonant channels. In the case of nonresonant saturation, the cosmic rays become magnetized and amplification saturates at higher magnetic fields. The precursor can extend out to 10{sup 17}-10{sup 18} cm and is potentially detectable. If resonant saturation occurs, the cosmic rays are scattered by turbulence and the precursor length will likely be much smaller. The dependence of precursor length on shock velocity has implications for electron heating. In the case of resonant saturation, this dependence is similar to that in the more familiar resonantly generated shock precursor, which when expressed in terms of the cosmic-ray diffusion coefficient kappav and shock velocity v{sub s} is kappav/v{sub s} . In the nonresonantly saturated case, the precursor length declines less quickly with increasing v{sub s} . Where precursor length proportional to 1/v{sub s} gives constant electron heating, this increased precursor length could be expected to lead to higher electron temperatures for nonresonant amplification. This should be expected at faster supernova remnant shocks than studied by previous works. Existing results and new data analysis of SN 1006 and Cas A suggest some observational support for this idea.

  8. De novo and salvage pathway precursor incorporation during DNA replication at the nuclear matrix

    International Nuclear Information System (INIS)

    Panzeter, P.L.

    1988-01-01

    Total nuclear DNA can be empirically subdivided into low salt-soluble (LS) DNA (75-80%), high salt-soluble (HS) DNA (18-23%), and nuclear matrix-associated (NM) DNA which remains tightly bound to the nuclear matrix (∼2%). The most-newly replicated DNA is that associated with the nuclear matrix in regenerating rat liver. Analyses of the DNA fractions after various pulse times revealed that the salvage and de novo pathway DNA precursors investigated were incorporated preferentially into NM-DNA at early pulse times, after which the radioactivity became progressively incorporated into HS- and LS-DNA, respectively. These results support two models of nuclear matrix-associated DNA replication, proposed previously, and a third model presented in this dissertation. In addition, the incorporation of de novo pathway precursors lagged significantly (> 10 minutes) behind the incorporation of precursors entering through the salvage pathway. Channeling of salvage pathway precursors to DNA replication sites would explain the more rapid uptake of salvage precursors into NM-DNA than de novo precursors. To investigate the possibility of this heretofore in vitro phenomenon, the incorporation of the salvage precursor, ( 3 H)deoxythymidine, and the de novo precursor, ( 14 C)orotic acid, into NM-DNA and dTTP was examined in regenerating rat liver. There was no significant difference between the incorporation pattern of ( 14 C)orotic acid into NM-DNA thymine and that of ( 14 C)orotic acid into soluble dTTP. Contrastingly, the salvage pathway precursor, ( 3 H)deoxythymidine, labeled NM-DNA before labeling the dTTP pool

  9. Optical precursors with tunneling-induced transparency in asymmetric quantum wells

    International Nuclear Information System (INIS)

    Peng Yandong; Qi Yihong; Yao Haifeng; Niu Yueping; Gong Shangqing

    2011-01-01

    A scheme for separating optical precursors from a square-modulated laser pulse through an asymmetric double Al x Ga 1-x As/GaAs quantum-well structure via resonant tunneling is proposed. Destructive interference inhibits linear absorption, and a tunneling-induced transparency (TIT) window appears with normal dispersion, which delays the main pulse; then optical precursors are obtained. Due to resonant tunneling, constructive interference for nonlinear susceptibility is created. The enhanced dispersion in a narrow TIT window is about one order of magnitude larger than that of the linear case. In this case, the main pulse is much delayed and the precursor signals are easier to obtain. Moreover, the main pulse builds up due to the gain introduced by the enhanced cross-nonlinearity.

  10. Replicable Expansion and Differentiation of Neural Precursors from Adult Canine Skin

    Directory of Open Access Journals (Sweden)

    Thomas Duncan

    2017-08-01

    Full Text Available Repopulation of brain circuits by neural precursors is a potential therapeutic strategy for neurodegenerative disorders; however, choice of cell is critical. Previously, we introduced a two-step culture system that generates a high yield of neural precursors from small samples of adult canine skin. Here, we probe their gene and protein expression profiles in comparison with dermal fibroblasts and brain-derived neural stem cells and characterize their neuronal potential. To date, we have produced >50 skin-derived neural precursor (SKN lines. SKNs can be cultured in a highly replicable fashion and uniformly express a panel of identifying markers. Upon differentiation, they self-upregulate neural specification genes, generating neurons with basic electrophysiological functionality. This unique population of neural precursors, derived from mature skin, overcomes many of the practical issues that have limited clinical translation of alternative cell types. Easily accessible, neuronally committed, and patient specific, SKNs may have potential for the treatment of brain disorders.

  11. Primary structure of the human follistatin precursor and its genomic organization

    International Nuclear Information System (INIS)

    Shimasaki, Shunichi; Koga, Makoto; Esch, F.

    1988-01-01

    Follistatin is a single-chain gonadal protein that specifically inhibits follicle-stimulating hormone release. By use of the recently characterized porcine follistatin cDNA as a probe to screen a human testis cDNA library and a genomic library, the structure of the complete human follistatin precursor as well as its genomic organization have been determined. Three of eight cDNA clones that were sequenced predicted a precursor with 344 amino acids, whereas the remaining five cDNA clones encoded a 317 amino acid precursor, resulting from alternative splicing of the precursor mRNA. Mature follistatins contain four contiguous domains that are encoded by precisely separated exons; three of the domains are highly similar to each other, as well as to human epidermal growth factor and human pancreatic secretory trypsin inhibitor. The genomic organization of the human follistatin is similar to that of the human epidermal growth factor gene and thus supports the notion of exon shuffling during evolution

  12. Marine bacterial transparent exopolymer particles (TEP) and TEP precursors: Characterization and RO fouling potential

    KAUST Repository

    Li, Sheng

    2015-10-31

    This paper investigated the characteristics and membrane fouling potential of bacterial transparent exopolymer particles (TEP)/TEP precursors released from two marine bacteria, Pseudidiomarina homiensis (P. homiensis) and Pseudoalteromonas atlantica (P. atlantica), isolated from the Red Sea. Results showed that both bacteria grew at the similar rate, but the production of TEP/TEP precursors from P. atlantica was higher than that from P. homiensis. During the 168. h of incubation time, production rates of TEP/TEP precursors from P. atlantica and P. homiensis were 0.30 and 0.08 xanthan gum eq. mg/L-h, respectively. Isolated bacterial TEP precursors were mainly biopolymer, and P. atlantica produced a significantly higher concentration of biopolymer than that produced by P. homiensis. TEP/TEP precursors from both marine bacteria possessed protein-like material and were very similar in composition to previously reported foulants isolated from a fouled reverse osmosis (RO) membrane. Bacterial TEP/TEP precursors mostly consisted of aliphatic hydrocarbon from amino acids and amide group carbon of proteins (around 55%). Bacterial TEP precursors caused obvious fouling on RO membranes, which may create an ideal environment for bacteria attachment and promote to biofouling.

  13. Electrical properties of a novel lead alkoxide precursor: Lead glycolate

    International Nuclear Information System (INIS)

    Tangboriboon, Nuchnapa; Pakdeewanishsukho, Kittikhun; Jamieson, Alexander; Sirivat, Anuvat; Wongkasemjit, Sujitra

    2006-01-01

    The reaction of lead acetate trihydrate Pb(CH 3 COO) 2 .3H 2 O and ethylene glycol, using triethylenetetramine (TETA) as a catalyst, provides in one step access to a polymer-like precursor of lead glycolate [-PbOCH 2 CH 2 O-]. On the basis of high-resolution mass spectroscopy, chemical analysis composition, FTIR, 13 C-solid state NMR and TGA, the lead glycolate precursor can be identified as a trimer structure. The FTIR spectrum demonstrates the characteristics of lead glycolate; the peaks at 1086 and 1042 cm -1 can be assigned to the C-O-Pb stretchings. The 13 C-solid state NMR spectrum gives notably only one peak at 68.639 ppm belonging to the ethylene glycol ligand. The phase transformations of lead glycolate and lead acetate trihydrate to lead oxide, their microstructures, and electrical properties were found to vary with increasing temperature. The lead glycolate precursor has superior electrical properties relative to those of lead acetate trihydrate, suggesting that the lead glycolate precursor can possibly be used as a starting material for producing electrical and semiconducting ceramics, viz. ferroelectric, anti-ferroelectric, and piezoelectric materials

  14. Synthesis and characterization of a boron-containing precursor for ZrB{sub 2} ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Tao, X.Y.; Xiang, Z.; Zhou, S.; Zhu, Y. [China Univ. of Mining and Technology, Xuzhou (China). School of Materials Science and Engineering; Qiu, W.; Zhao, T. [Chinese Academy of Sciences, Beijing (China). Lab. of Advanced Polymer Materials

    2016-07-01

    A precursor for ZrB{sub 2} ceramic was successfully synthesized in a chemical reaction between polyzirconoxanesal (PZS) and boric acid. The molecular structure of the precursor, thermal properties and the pyrolysis behavior of the precursor were investigated. The results showed that the as-synthesized precursor was a polymer based on Zr-O-C-B bonds. The precursor was stable in air atmosphere and soluble in common organic solvents. The ceramic yield of the precursor at 1200 C was around 65.5 % under N{sub 2} atmosphere. The derived ceramics obtained at 1200 C were composed of B{sub 2}O{sub 3}, ZrO{sub 2} and carbon. When the temperature was increased up to 1300 C, peaks of ZrC emerged owing to carbothermal reduction. m-ZrO{sub 2} and t-ZrO{sub 2} disappeared when the pyrolysis temperature was increased to above 1400 C. ZrB{sub 2} became the predominant phase when the pyrolysis temperature was increased up to 1500 C.

  15. IL-9-Producing Mast Cell Precursors and Food Allergy

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-15-1-0517 TITLE: IL-9-Producing Mast Cell Precursors and Food Allergy PRINCIPAL INVESTIGATOR: Dr. Simon P. Hogan PhD...IL-9-Producing Mast Cell Precursors and Food Allergy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Yui Hsi Wang, Sunil...threatening anaphylaxis. We have identified a novel multi-functional IL-9-producing mucosal mast cells (MMC9s) that produce large amounts of IL-9, IL

  16. XANES- and EXAFS-Investigations on Chromium-Doped Mullite Precursors

    OpenAIRE

    Arzberger , I.; Küper , G.; Pantelouris , A.; Peitz , B.; Hormes , J.; Schneider , H.; Saruhan , B.

    1997-01-01

    Chromium-doped non-crystalline mullite precursors for ceramics were investigated with x-ray absorption spectroscopy at the Cr K edge. They were prepared using a sol-gel-route. 3 wt% Cr2O3 were added to partially substitute aluminium by chromium in the aluminosilicate network. The aim of the study was to characterize the development of the electronic and geometric structure of the precursor at different temperatures prior to its crystallization to mullite. The x-ray absorption spectra of the p...

  17. DISERTACIÓN SOBRE JUSTICIA Y EQUIDAD

    Directory of Open Access Journals (Sweden)

    Sayuri P. Tamura M.

    2001-01-01

    Full Text Available «Disertación sobre equidad y justicia» es básicamente una respuesta a una inquietud en particular que yo tenía sobre las distintas posiciones que existen sobre estos dos temas y cómo definir cuál es la más acertada. Hice una descripción del punto de vista de Amartya Sen –la violación de los derechos sobre la propiedad privada es justificable si evitan las hambrunas2– frente al de Robert Nozick –la propiedad privada es un derecho fundamental y como tal debe ser respetado3–, sin embargo, aunque ambos enfoques son totalmente contrarios tienen mucho sentido, por lo cual es bastante difícil decidirse por uno en particular. Fue de esta forma, enfrentando sus opiniones, que yo logré desarrollar una posición frente a estas dos perspectivas, y así dar mi opinión al DISERTACIÓN SOBRE JUSTICIA Y EQUIDAD SAYURI P. TAMURA M. Estudiante de Economía y Negocios Internacionales de la Universidad ICESI. respecto. Al final, llegué a una conclusión, que aunque no es la más original y tampoco es la única, tiene mucho sentido y seguramente de ser posible, la situación del país podría cambiar para bien.

  18. Correlation of precursor and product ions in single-stage high resolution mass spectrometry. A tool for detecting diagnostic ions and improving the precursor elemental composition elucidation

    Energy Technology Data Exchange (ETDEWEB)

    Borràs, S. [Departament de Química Analítica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona (Spain); Kaufmann, A., E-mail: anton.kaufmann@klzh.ch [Official Food Control Authority, Fehrenstrasse 15, 8032 Zürich (Switzerland); Companyó, R. [Departament de Química Analítica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona (Spain)

    2013-04-15

    Highlights: ► We are describing a technique to spot ions which are derived from each other. ► Single stage high resolution data is used. ► This “in silicon” technique is compared to conventional precursor scan. ► Some applications for this technique are presented. -- Abstract: Monitoring of common diagnostic fragments is essential for recognizing molecules which are members of a particular compound class. Up to now, unit resolving tandem quadrupole mass spectrometers, operating in the precursor ion scan mode, have been typically used to perform such analysis. By means of high-resolution mass spectrometry (HRMS) a much more sensitive and selective detection can be achieved. However, using a single-stage HRMS instrument, there is no unequivocal link to the corresponding precursor ion, since such instrumentation does not permit a previous precursor selection. Thus, to address this limitation, an in silico approach to locate precursor ions, based on diagnostic fragments, was developed. Implemented as an Excel macro, the algorithm rapidly assembles and surveys exact mass data to provide a list of feasible precursor candidates according to the correlation of the chromatographic peak shape profile and other additional filtering criteria (e.g. neutral losses and isotopes). The macro was tested with two families of veterinary drugs, sulfonamides and penicillins, which are known to yield diagnostic product ions when fragmented. Data sets obtained from different food matrices (fish and liver), both at high and low concentration of the target compounds, were investigated in order to evaluate the capabilities and limitations of the reported approach. Finally, other possible applications of this technique, such as the elucidation of elemental compositions based on product ions and corresponding neutral losses, were also presented and discussed.

  19. Correlation of precursor and product ions in single-stage high resolution mass spectrometry. A tool for detecting diagnostic ions and improving the precursor elemental composition elucidation

    International Nuclear Information System (INIS)

    Borràs, S.; Kaufmann, A.; Companyó, R.

    2013-01-01

    Highlights: ► We are describing a technique to spot ions which are derived from each other. ► Single stage high resolution data is used. ► This “in silicon” technique is compared to conventional precursor scan. ► Some applications for this technique are presented. -- Abstract: Monitoring of common diagnostic fragments is essential for recognizing molecules which are members of a particular compound class. Up to now, unit resolving tandem quadrupole mass spectrometers, operating in the precursor ion scan mode, have been typically used to perform such analysis. By means of high-resolution mass spectrometry (HRMS) a much more sensitive and selective detection can be achieved. However, using a single-stage HRMS instrument, there is no unequivocal link to the corresponding precursor ion, since such instrumentation does not permit a previous precursor selection. Thus, to address this limitation, an in silico approach to locate precursor ions, based on diagnostic fragments, was developed. Implemented as an Excel macro, the algorithm rapidly assembles and surveys exact mass data to provide a list of feasible precursor candidates according to the correlation of the chromatographic peak shape profile and other additional filtering criteria (e.g. neutral losses and isotopes). The macro was tested with two families of veterinary drugs, sulfonamides and penicillins, which are known to yield diagnostic product ions when fragmented. Data sets obtained from different food matrices (fish and liver), both at high and low concentration of the target compounds, were investigated in order to evaluate the capabilities and limitations of the reported approach. Finally, other possible applications of this technique, such as the elucidation of elemental compositions based on product ions and corresponding neutral losses, were also presented and discussed

  20. Adsorption of N-nitrosodimethylamine precursors by powdered and granular activated carbon.

    Science.gov (United States)

    Hanigan, David; Zhang, Jinwei; Herckes, Pierre; Krasner, Stuart W; Chen, Chao; Westerhoff, Paul

    2012-11-20

    Activated carbon (AC) has been shown to remove precursors of halogenated disinfection byproducts. Granular and powdered activated carbon (GAC, PAC) were investigated for their potential to adsorb N-nitrosodimethylamine (NDMA) precursors from blends of river water and effluent from a wastewater treatment plant (WWTP). At bench scale, waters were exposed to lignite or bituminous AC, either as PAC in bottle point experiments or as GAC in rapid small-scale column tests (RSSCTs). NDMA formation potential (FP) was used as a surrogate for precursor removal. NDMA FP was reduced by 37, 59, and 91% with 3, 8, and 75 mg/L of one PAC, respectively, with a 4-h contact time. In RSSCTs and in full-scale GAC contactors, NDMA FP removal always exceeded that of the bulk dissolved organic carbon (DOC) and UV absorbance at 254 nm. For example, whereas DOC breakthrough exceeded 90% of its influent concentration after 10,000 bed volumes of operation in an RSSCT, NDMA FP was less than 40% of influent concentration after the same bed life of the GAC. At full or pilot scale, high NDMA FP reduction ranging from >60 to >90% was achieved across GAC contactors, dependent upon the GAC bed life and/or use of a preoxidant (chlorine or ozone). In all experiments, NDMA formation was not reduced to zero, which suggests that although some precursors are strongly sorbed, others are not. This is among the first studies to show that AC is capable of adsorbing NDMA precursors, but further research is needed to better understand NDMA precursor chemical properties (e.g., hydrophobicity, molecular size) and evaluate how best to incorporate this finding into full-scale designs and practice.

  1. Thermoset precursor

    International Nuclear Information System (INIS)

    Yamamoto, Y.

    1983-04-01

    This invention pertains to a distinctive thermoset precursor which is prepared by mixing a resin composition (A) which can be hardened by ionizing radiation, and a resin composition (B) which can be hardened by heat but cannot be hardened by, or is resistant to, ionizing radiation, and by coating or impregnating a molding or other substrate with a sheet or film of this mixture and irradiating this with an ionizing radiation. The principal components of composition (A) and (B) can be the following: (1) an acrylate or methacrylate and an epoxy resin and an epoxy resin hardener; (2) an unsaturated polyester resin and epoxy resin and an epoxy resin hardener; (3) a diacrylate or dimethacrylate or polyethylene glycol and an epoxy resin; (4) an epoxy acrylates or epoxy methacrylate obtained by the addition reaction of epoxy resin and acrylic or methacrylic acid

  2. Molecular pathogenesis of precursor lesions of pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Biankin, Andrew V; Kench, James G; Dijkman, Floriaan P; Biankin, Sandra A; Henshall, Susan M

    2003-02-01

    Precursor lesions are assuming greater importance in the study of pancreatic ductal adenocarcinoma. As pancreatic cancer is almost universally fatal due to late clinical presentation and biological aggressiveness, characterisation of its precursor lesions may create scope for early diagnosis and improved outcome with conventional therapies as well as the development of novel therapeutic and preventative strategies. Pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous tumours (IPMTs) are thought to be precursor lesions of ductal adenocarcinoma of the pancreas. Recent work has focused on the molecular aberrations associated with these lesions leading to the formulation of a progression model for pancreatic cancer. Progressive histopathological changes along the progression model are associated with aberrations of cell cycle regulatory and growth factor signalling molecules that occur in pancreatic cancer at high frequency and are common to many cancers. Characterisation of these molecular aberrations provides scope for the development of novel diagnostic and treatment strategies that will ultimately impact on the outcome for people who develop pancreatic cancer.

  3. Early postradiation recovery of precursor cells of hemopoietic stroma

    International Nuclear Information System (INIS)

    Todriya, T.V.

    1984-01-01

    Ability of stroma precursor cells to early postradiation recovery was studied in male mices using the method of fraction irradiation of bone marrow. Donor mices of bone marrow were irradiated in vivo once by the total dose (nonfraction irradiation) and fractionally with 6 h interval between two irradiation doses. The cumulative irradiation doses equal to 10, 12, 14, 16 Gr were investigated. Irradiation was carried out using gamma facility. Bone marrow of the femur was implanted immediately after irradiation under kidney capsule of nonirradiated syngeneic recipient. The ability of stroma precursor cells to intracellular repair (repair index) was evaluated according to the ratio of the number of hemopoietic cells formed in heterotropic transplants in groups with fraction irradiation to the same one in groups with nonfraction irradiation. The obtained results testify to the fact that slowly regenerated highly radioresistant population of precursor cells of hemopoietic stroma is capable to early postradiation recovery

  4. Fluorinated Phenylalanine Precursor Resistance in Yeast

    Directory of Open Access Journals (Sweden)

    Ian S. Murdoch

    2018-06-01

    Full Text Available Development of a counter-selection method for phenylalanine auxotrophy could be a useful tool in the repertoire of yeast genetics. Fluorinated and sulfurated precursors of phenylalanine were tested for toxicity in Saccharomyces cerevisiae. One such precursor, 4-fluorophenylpyruvate (FPP, was found to be toxic to several strains from the Saccharomyces and Candida genera. Toxicity was partially dependent on ARO8 and ARO9, and correlated with a strain’s ability to convert FPP into 4-fluorophenylalanine (FPA. Thus, strains with deletions in ARO8 and ARO9, having a mild phenylalanine auxotrophy, could be separated from a culture of wild-type strains using FPP. Tetrad analysis suggests FPP resistance in one strain is due to two genes. Strains resistant to FPA have previously been shown to exhibit increased phenylethanol production. However, FPP resistant isolates did not follow this trend. These results suggest that FPP could effectively be used for counter-selection but not for enhanced phenylethanol production.

  5. Precursors of nitrogenous disinfection by-products in drinking water--A critical review and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Tom [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Templeton, Michael R.; Graham, Nigel [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ (United Kingdom)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer The proportion of N-DBP formation attributable to specific precursors was calculated. Black-Right-Pointing-Pointer Precursor concentrations are typically insufficient to account for observed N-DBP formation, except CNX and NDMA. Black-Right-Pointing-Pointer Amino acid precursors are easier to remove during water treatment than suggested by laboratory studies. - Abstract: In recent years research into the formation of nitrogenous disinfection by-products (N-DBPs) in drinking water - including N-nitrosodimethylamine (NDMA), the haloacetonitriles (HANs), haloacetamides (HAcAms), cyanogen halides (CNX) and halonitromethanes (HNMs) - has proliferated. This is partly due to their high reported toxicity of N-DBPs. In this review paper information about the formation yields of N-DBPs from model precursors, and about environmental precursor occurrence, has been employed to assess the amount of N-DBP formation that is attributable to known precursors. It was calculated that for HANs and HAcAms, the concentrations of known precursors - mainly free amino acids are insufficient to account for the observed concentrations of these N-DBP groups. However, at least in some waters, a significant proportion of CNX and NDMA formation can be explained by known precursors. Identified N-DBP precursors tend to be of low molecular weight and low electrostatic charge relative to bulk natural organic matter (NOM). This makes them recalcitrant to removal by water treatment processes, notably coagulation, as confirmed by a number of bench-scale studies. However, amino acids have been found to be easier to remove during water treatment than would be suggested by the known molecular properties of the individual free amino acids.

  6. Fitoextração de sais pela Atriplex nummularia lindl. sob estresse hídrico em solo salino sódico Phytoextraction of salts by Atriplex nummularia lindl. under water stress in saline sodic soils

    Directory of Open Access Journals (Sweden)

    Edivan R. de Souza

    2011-05-01

    Full Text Available Objetivou-se avaliar a extração de sais pela Atriplex cultivada em solo salino sódico sob condições de estresse hídrico e comparar propriedades do solo antes e após seu cultivo. O experimento foi desenvolvido em casa de vegetação durante 134 dias, com cultivo em vasos com 20 kg de solo salino sódico em quatro níveis de umidade (35, 55, 75 e 95% da capacidade de campo, com um tratamento controle (sem cultivo, montado em blocos casualizados, com oito repetições. As altas concentrações de Ca2+, Mg2+, K+ e, especialmente Na+ e Cl- nas folhas de Atriplex nummularia, associadas à elevada produção de massa seca, caracterizam esta espécie como planta fitoextratora de sais, chegando a extrair, nas folhas e caule, o equivalente a: 644,25; 757,81; 1.058,55 e 1.182,00 kg ha-1 desses elementos, para 35, 55, 75 e 95% da capacidade de campo, respectivamente. As variáveis do complexo sortivo do solo (Ca2+, Mg2+, K+, soma de bases e o carbono orgânico total, permaneceram estáveis entre o início e o final do experimento, em todos os tratamentos, enquanto o Na+ e a percentagem de sódio trocável diminuíram após o cultivo da planta. A Atriplex respondeu ao incremento de umidade do solo quando se considera a produção de biomassa e a extração de sais.This study aims to evaluate the growth, production and extraction of salts by Atriplex grown on saline-sodic soil under water stress conditions and to compare soil properties before and after their cultivation. The experiment was carried out in a greenhouse during 134 days growing Atriplex nummularia in pots with 20 kg of saline sodic soil with four levels of soil moisture (35, 55, 75 and 95% of field capacity with a control (soil without plant. The experiment was performed in a randomized block with eight replications. The high concentrations of Ca2+, Mg2+, K+, and especially Na+ and Cl- in leaves of Atriplex nummularia, associated with high dry matter production characterizes this species

  7. Nano structured TiO2 thin films by polymeric precursor method

    International Nuclear Information System (INIS)

    Stroppa, Daniel Grando; Giraldi, Tania Regina; Leite, Edson Roberto; Varela, Jose Arana; Longo, Elson

    2008-01-01

    This work focuses in optimizing setup for obtaining TiO 2 thin films by polymeric precursor route due to its advantages on stoichiometric and morphological control. Precursor stoichiometry, synthesis pH, solids concentration and rotation speed at deposition were optimized evaluating thin films morphology and thickness. Thermogravimetry and NMR were applied for precursor's characterization and AFM, XRD and ellipsometry for thin films evaluation. Results showed successful attainment of homogeneous nanocrystalline anatase TiO 2 thin films with outstanding control over morphological characteristics, mean grain size of 17 nm, packing densities between 57 and 75%, estimated surface areas of 90 m 2 /g and monolayers thickness within 20 and 128 nm. (author)

  8. Produção de lodo e comportamento químico de sais de ferro empregados no pós-tratamento de esgoto sanitário por precipitação química

    OpenAIRE

    Ferreira Filho,Sidney Seckler; Marguti,André Luiz; Piveli,Roque Passos

    2009-01-01

    A combinação de processos físico-químicos e biológicos no tratamento de esgotos sanitários tem se apresentado como uma alternativa na remoção de fósforo. No entanto, uma das limitações é a sua maior produção de lodo. Desse modo, este trabalho teve por objetivo avaliar a produção de lodo resultante da aplicação de sais de ferro para diferentes tipos de efluentes, bem como estudar o impacto de sua aplicação nas características físico-químicas dos efluentes estudados. Concluiu-se que os valores ...

  9. Laser synthesis of nanostructured ceramics from liquid precursors

    International Nuclear Information System (INIS)

    Wilden, Johannes; Fischer, Georg

    2007-01-01

    The free-form net shape laser synthesis of nanostructured ceramics from liquid precursors enables a residual stress-free production of high temperature resistant ceramic units and components for the use in microsystem engineering. Due to the use of molecular compounded liquid, ceramic precursors the resulting ceramic components show outstanding properties, for example high purity and a nanostructured material design. The use of pulsed lasers enables a defined input of energy required to pyrolyse the precursor material into a crystalline ceramic, so the active volume can be reduced significantly compared to other processes, for example pyrolysis by furnace. In this paper several methods for a further minimization of the active volume are presented. The investigations determined different factors affecting the process. Realizing selective experiments allows a determination of their influencing level and the definition of a working area to produce three-dimensional components with high aspect ratio. By several studies, e.g., scanning electron microscopy, transmission electron microscopy as well as X-ray diffraction analysis, the atomic structure and composition of the created components were analyzed and valued, so the different reaction processes can be described extensively

  10. Resposta à regeneração e crescimento de brotos in vitro de Kielmeyera coriacea quando influenciado por diferentes concentrações dos sais e de sacarose In vitro regeneration and growth response of Kielmeyera coriacea shoots when affected by salts and sucrose concentrations

    Directory of Open Access Journals (Sweden)

    José Eduardo Brasil Pereira Pinto

    1996-04-01

    Full Text Available Avaliaram-se diferentes concentrações de sacarose e sais do MS (MURASHIGE & SKOOG, J 962 na regeneração e crescimento de brotos de Kielmeyera coriacea in vitro. A redução e o aumento da quantidade de sacarose partindo de 30 e 45g/L, respectivamente, causou um decréscimo no número total de brotos. O uso integral ou da metade das concentrações dos sais do MS proporcionou maiores taxas de multiplicação. A maior porcentagem de brotos com mais de 1,0cm de comprimento pôde ser obtida empregando-se 30 g/l de sacarose associado a concentração 1/1 do MS. A porcentagem média de brotos decresceu linearmente com a diluição salina.Trials were carried out to test sucrose and salt concentrations added to growth medium on regeneration and growth response of Kielmeyera coriacea shoots. The reduction and increase of sucrose of 30 and 45g/l, rerspectively, caused a decrease in total number of shoots. A higher shoots percentage of with more than 1.0cm, occurred on media with 30g/L of sucrose. The use of total force (1/1 and half strength (1/2 of MS salt proportioned a higher shoot ratio and growth.

  11. Understanding Animal Detection of Precursor Earthquake Sounds.

    Science.gov (United States)

    Garstang, Michael; Kelley, Michael C

    2017-08-31

    We use recent research to provide an explanation of how animals might detect earthquakes before they occur. While the intrinsic value of such warnings is immense, we show that the complexity of the process may result in inconsistent responses of animals to the possible precursor signal. Using the results of our research, we describe a logical but complex sequence of geophysical events triggered by precursor earthquake crustal movements that ultimately result in a sound signal detectable by animals. The sound heard by animals occurs only when metal or other surfaces (glass) respond to vibrations produced by electric currents induced by distortions of the earth's electric fields caused by the crustal movements. A combination of existing measurement systems combined with more careful monitoring of animal response could nevertheless be of value, particularly in remote locations.

  12. Functional Nanoporous Polymers from Block Copolymer Precursors

    DEFF Research Database (Denmark)

    Guo, Fengxiao

    Abstract Self-assembly of block copolymers provides well-defined morphologies with characteristic length scales in the nanometer range. Nanoporous polymers prepared by selective removal of one block from self-assembled block copolymers offer great technological promise due to their many potential...... functionalities remains a great challenge due to the limitation of available polymer synthesis and the nanoscale confinement of the porous cavities. The main topic of this thesis is to develop methods for fabrication of functional nanoporous polymers from block copolymer precursors. A method has been developed......, where living anionic polymerization and atom transfer radical polymerization (ATRP) are combined to synthesize a polydimethylsiloxane-b-poly(tert-butyl acrylate)-b-polystyrene (PDMS-b-PtBA-b-PS) triblock copolymer precursor. By using either anhydrous hydrogen fluoride or trifluoroacetic acid, PtBA block...

  13. A possible island of beta-delayed neutron precursors in heavy nucleus region

    International Nuclear Information System (INIS)

    Zhang Li

    1991-01-01

    The possible Beta-Delayed neutron precursors in the elements Tl, Hg, and Au were predicted following a systematic research on the known Beta-Delayed neutron precursors. The masses of the unknown nuclei and neutron emission probabilities were calculated

  14. Kinetic and Surface Study of Single-Walled Aluminosilicate Nanotubes and Their Precursors

    Directory of Open Access Journals (Sweden)

    Mauricio Molina

    2013-03-01

    Full Text Available The structural and surface changes undergone by the different precursors that are produced during the synthesis of imogolite are reported. The surface changes that occur during the synthesis of imogolite were determined by electrophoretic migration (EM measurements, which enabled the identification of the time at which the critical precursor of the nanoparticles was generated. A critical parameter for understanding the evolution of these precursors is the isoelectric point (IEP, of which variation revealed that the precursors modify the number of active ≡Al-OH and ≡Si-OH sites during the formation of imogolite. We also found that the IEP is displaced to a higher pH level as a consequence of the surface differentiation that occurs during the synthesis. At the same time, we established that the pH of the reaction (pHrx decreases with the evolution and condensation of the precursors during aging. Integration of all of the obtained results related to the structural and surface properties allows an overall understanding of the different processes that occur and the products that are formed during the synthesis of imogolite.

  15. Precursors to potential severe core damage accidents. A status report, 1982--1983

    Energy Technology Data Exchange (ETDEWEB)

    Forester, J.A.; Mitchell, D.B.; Whitehead, D.W. [and others

    1997-04-01

    This study is a continuation of earlier work that evaluated 1969-1981 and 1984-1994 events affecting commercial light-water reactors. One-hundred nine operational events that affected 51 reactors during 1982 and 1983 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10{sup {minus}6}. These events were identified by first computer screening the 1982-83 licensee event reports from commercial light-water reactors to select events that could be precursors to core damage. Candidates underwent engineering evaluation that identified, analyzed, and documented the precursors. This report discusses the general rationale for the study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events.

  16. Precursors to potential severe core damage accidents. A status report, 1982--1983

    International Nuclear Information System (INIS)

    Forester, J.A.; Mitchell, D.B.; Whitehead, D.W.

    1997-04-01

    This study is a continuation of earlier work that evaluated 1969-1981 and 1984-1994 events affecting commercial light-water reactors. One-hundred nine operational events that affected 51 reactors during 1982 and 1983 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by first computer screening the 1982-83 licensee event reports from commercial light-water reactors to select events that could be precursors to core damage. Candidates underwent engineering evaluation that identified, analyzed, and documented the precursors. This report discusses the general rationale for the study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for the events

  17. Influence of Pd-precursor on the acetoxylation activity of Pd-Sb/TiO{sub 2} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Ben-homeid, A. [Benghazi Univ. (Libyan Arab Jamahiriya). Chemistry Dept.; Kalevaru, V.N.; Radnik, J.; Luecke, B.; Martin, A. [Leibniz-Institut fuer Katalyse e.V. an der Universitaet Rostock (Germany)

    2013-11-01

    The impact of palladium precursors (e.g. chloride-PdCl{sub 2}; acetate-Pd(OAc){sub 2}; nitrate-Pd(NO{sub 3}){sub 2}) on the catalytic properties of Pd-Sb/TiO{sub 2} catalysts used for acetoxylation of toluene has been investigated. The catalysts were characterized by different techniques such as N{sub 2}-adsorption (BET-surface area and pore volume), XRD, TEM, CO-Chemisorption and XPS for better understanding of the catalytic properties of the catalysts. The acetate and nitrate-type precursors exhibited higher surface areas, pore volumes and higher dispersion of Pd, but displayed poor performance compared to chloride precursor. TEM analysis indicated that the size of Pd particles depended upon the nature of Pd-precursor. Among the three, chloride precursor exhibited bigger Pd particles. XPS results revealed that all the fresh catalysts irrespective of Pd-precursor contained Pd in oxidized state (i.e. Pd{sup +2}), while in the spent catalysts such oxidized Pd species were reduced. The catalytic performance was found to depend strongly on the nature of precursor used. Among the three, the catalysts prepared from chloride-type precursor showed much higher overall catalytic activity (68%) than those of nitrate and/or acetate type precursors. Moreover, these two precursors (acetate and nitrate) gave higher total oxidation products due to oxidative decomposition of mainly acetic acid. Furthermore, the catalyst prepared from Cl-precursor revealed easy deactivation due to coke deposition and also due to loss of Pd in the near-surface-region. (orig.)

  18. Maakondade rahvakultuuri aastapreemiad 2001

    Index Scriptorium Estoniae

    2002-01-01

    Fr. R. Kreutzwaldi nim mälestusmedali ja Kreutzwaldi-stipendiumi statuudid, lk. 89-00. Hendrik Lindepuu sai Jõgevamaa kirjanduspreemia; Mari Vallisoo sai Juhan Liivi nim. luuleauhinna, Elle-Eha Are sai Viljandimaa kultuuripreemia ja Contra B. Kangro nim. kirjanduspreemia. F. R. Kreutzwaldi mälestusmedali sai Aarand Roos

  19. From chelating precursors to La0.05Sr0.95CoO3-y oxide

    International Nuclear Information System (INIS)

    Hong, L.; Guo, F.; Lin, J.

    1999-01-01

    Several La 0.05 Sr 0.95 CoO 3-y (LSCO-95) powders were synthesized by means of a chelated complex-based precursor approach, which involved pyrolysis of chelating precursors and subsequent calcination of the resulting oxides. This paper focuses on the coordination effects of the precursors on the formation of the crystalline phases of the LSCO-95 oxide, showing that when the precursor is composed of EDTA-metal complexes, the perovskite-type oxide LSCO-95, an electronic-ionic mixed conducting ceramic material, can be achieved. In contrast, those LSCO-95 powders obtained initially from the pyrolysis of the precursors containing other coordination ligands possess only the undesirable hexagonal structure

  20. Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Shafarman, William N. [Univ. of Delaware, Newark, DE (United States)

    2015-10-12

    This project “Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells”, completed by the Institute of Energy Conversion (IEC) at the University of Delaware in collaboration with the Department of Chemical Engineering at the University of Florida, developed the fundamental understanding and technology to increase module efficiency and improve the manufacturability of Cu(InGa)(SeS)2 films using the precursor reaction approach currently being developed by a number of companies. Key results included: (1) development of a three-step H2Se/Ar/H2S reaction process to control Ga distribution through the film and minimizes back contact MoSe2 formation; (2) Ag-alloying to improve precursor homogeneity by avoiding In phase agglomeration, faster reaction and improved adhesion to allow wider reaction process window; (3) addition of Sb, Bi, and Te interlayers at the Mo/precursor junction to produce more uniform precursor morphology and improve adhesion with reduced void formation in reacted films; (4) a precursor structure containing Se and a reaction process to reduce processing time to 5 minutes and eliminate H2Se usage, thereby increasing throughput and reducing costs. All these results were supported by detailed characterization of the film growth, reaction pathways, thermodynamic assessment and device behavior.

  1. Apical Polarity Protein PrkCi Is Necessary for Maintenance of Spinal Cord Precursors in Zebrafish

    OpenAIRE

    Roberts, Randolph K.; Appel, Bruce

    2009-01-01

    During development, neural precursors divide to produce new precursors and cells that differentiate as neurons and glia. In Drosophila, apicobasal polarity and orientation of the mitotic spindle play important roles in specifying the progeny of neural precursors for different fates. We examined orientation of zebrafish spinal cord precursors using time-lapse imaging and tested the function of protein kinase C, iota (PrkCi), a member of the Par complex of proteins necessary for apicobasal pola...

  2. Somos un envase : Discursos sobre el aborto

    OpenAIRE

    Löcher, Jennifer Irene

    2014-01-01

    No hay persona que no tenga opinión acerca del asunto y, cada vez más, la sociedad argentina debate sobre la pregunta de si se debe legalizar/despenalizar el aborto o no. Nunca antes se habló tanto sobre el tema públicamente: se publican artículos en los diarios, hay manifestaciones a favor y hay manifestaciones en contra de la legalización del aborto. El siguiente trabajo pretende relevar y analizar discursos que circulan socialmente alrededor del debate sobre el aborto. (Párrafo extraíd...

  3. Technical Note: Methionine, a precursor of methane in living plants

    Science.gov (United States)

    Lenhart, K.; Althoff, F.; Greule, M.; Keppler, F.

    2015-03-01

    When terrestrial plants were identified as producers of the greenhouse gas methane, much discussion and debate ensued not only about their contribution to the global methane budget but also with regard to the validity of the observation itself. Although the phenomenon has now become more accepted for both living and dead plants, the mechanism of methane formation in living plants remains to be elucidated and its precursor compounds to be identified. We made use of stable isotope techniques to verify the in vivo formation of methane, and, in order to identify the carbon precursor, 13C positionally labeled organic compounds were employed. Here we show that the amino acid L-methionine acts as a methane precursor in living plants. Employing 13C-labeled methionine clearly identified the sulfur-bound methyl group of methionine as a carbon precursor of methane released from lavender (Lavandula angustifolia). Furthermore, when lavender plants were stressed physically, methane release rates and the stable carbon isotope values of the emitted methane greatly increased. Our results provide additional support that plants possess a mechanism for methane production and suggest that methionine might play an important role in the formation of methane in living plants, particularly under stress conditions.

  4. Dynamics of fibrillar precursors of shishes as a function of stress

    Energy Technology Data Exchange (ETDEWEB)

    Balzano, Luigi; Cavallo, Dario; Van Erp, Tim B; Ma Zhe; Housmans, Jan-Willem; Fernandez-Ballester, Lucia; Peters, Gerrit W M, E-mail: G.W.M.Peters@tue.n

    2010-11-15

    Shishes are fibrillar crystallites that can be created by deforming a polymer melt. The formation of shishes takes place when flow is strong enough to stretch molecules. In the early stages, bundles of stretched molecules with pre-crystalline order form metastable precursors whose stability depends on their size and, hence, on the stress level. We find that for a specific isotactic polypropylene, close to the nominal melting point, a stress larger than 0.10 MPa leads to stable fibrillar precursors that are partially crystalline immediately after flow. On the other hand, below 0.10 MPa, the aspect ratio of precursors tends to unity and the lack of crystallinity makes these structures prone to dissolution.

  5. Applying polarity rapid assessment method and ultrafiltration to characterize NDMA precursors in wastewater effluents.

    Science.gov (United States)

    Chen, Chao; Leavey, Shannon; Krasner, Stuart W; Mel Suffet, I H

    2014-06-15

    Certain nitrosamines in water are disinfection byproducts that are probable human carcinogens. Nitrosamines have diverse and complex precursors that include effluent organic matter, some anthropogenic chemicals, and natural (likely non-humic) substances. An easy and selective tool was first developed to characterize nitrosamine precursors in treated wastewaters, including different process effluents. This tool takes advantages of the polarity rapid assessment method (PRAM) and ultrafiltration (UF) (molecular weight distribution) to locate the fractions with the strongest contributions to the nitrosamine precursor pool in the effluent organic matter. Strong cation exchange (SCX) and C18 solid-phase extraction cartridges were used for their high selectivity for nitrosamine precursors. The details of PRAM operation, such as cartridge clean-up, capacity, pH influence, and quality control were included in this paper, as well as the main parameters of UF operation. Preliminary testing of the PRAM/UF method with effluents from one wastewater treatment plant gave very informative results. SCX retained 45-90% of the N-nitrosodimethylamine (NDMA) formation potential (FP)-a measure of the precursors-in secondary and tertiary wastewater effluents. These results are consistent with NDMA precursors likely having a positively charged amine group. C18 adsorbed 30-45% of the NDMAFP, which indicates that a substantial portion of these precursors were non-polar. The small molecular weight (MW) (10 kDa) fractions obtained from UF were the primary contributors to NDMAFP. The combination of PRAM and UF brings important information on the characteristics of nitrosamine precursors in water with easy operation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Trayectorias (sobre ruedas): un ensayo visual sobre los carritos de supermercado en la ciudad

    OpenAIRE

    Cruz, Edgar Gómez

    2014-01-01

    El siguiente trabajo es un breve bosquejo de las posibilidades del concepto de trabajo “trayectoria”. Una trayectoria no es sólo, en el sentido literal del término, el trazo del movimiento sobre un camino, sino que busca establecer una reflexión sobre las posibilidades de recolección de registros visuales/digitales/móviles para la investigación etnográfica desde la aleatoriedad del movimiento por la ciudad. El concepto de trayectoria busca dialogar con el de “flâneur” de De Certeau y Benjamin...

  7. Thin films by metal-organic precursor plasma spray

    International Nuclear Information System (INIS)

    Schulz, Douglas L.; Sailer, Robert A.; Payne, Scott; Leach, James; Molz, Ronald J.

    2009-01-01

    While most plasma spray routes to coatings utilize solids as the precursor feedstock, metal-organic precursor plasma spray (MOPPS) is an area that the authors have investigated recently as a novel route to thin film materials. Very thin films are possible via MOPPS and the technology offers the possibility of forming graded structures by metering the liquid feed. The current work employs metal-organic compounds that are liquids at standard temperature-pressure conditions. In addition, these complexes contain chemical functionality that allows straightforward thermolytic transformation to targeted phases of interest. Toward that end, aluminum 3,5-heptanedionate (Al(hd) 3 ), triethylsilane (HSi(C 2 H 5 ) 3 or HSiEt 3 ), and titanium tetrakisdiethylamide (Ti(N(C 2 H 5 ) 2 ) 4 or Ti(NEt 2 ) 4 ) were employed as precursors to aluminum oxide, silicon carbide, and titanium nitride, respectively. In all instances, the liquids contain metal-heteroatom bonds envisioned to provide atomic concentrations of the appropriate reagents at the film growth surface, thus promoting phase formation (e.g., Si-C bond in triethylsilane, Ti-N bond in titanium amide, etc.). Films were deposited using a Sulzer Metco TriplexPro-200 plasma spray system under various experimental conditions using design of experiment principles. Film compositions were analyzed by glazing incidence x-ray diffraction and elemental determination by x-ray spectroscopy. MOPPS films from HSiEt 3 showed the formation of SiC phase but Al(hd) 3 -derived films were amorphous. The Ti(NEt 2 ) 4 precursor gave MOPPS films that appear to consist of nanosized splats of TiOCN with spheres of TiO 2 anatase. While all films in this study suffered from poor adhesion, it is anticipated that the use of heated substrates will aid in the formation of dense, adherent films.

  8. Precursors of nitrogenous disinfection by-products in drinking water––A critical review and analysis

    International Nuclear Information System (INIS)

    Bond, Tom; Templeton, Michael R.; Graham, Nigel

    2012-01-01

    Highlights: ► The proportion of N-DBP formation attributable to specific precursors was calculated. ► Precursor concentrations are typically insufficient to account for observed N-DBP formation, except CNX and NDMA. ► Amino acid precursors are easier to remove during water treatment than suggested by laboratory studies. - Abstract: In recent years research into the formation of nitrogenous disinfection by-products (N-DBPs) in drinking water – including N-nitrosodimethylamine (NDMA), the haloacetonitriles (HANs), haloacetamides (HAcAms), cyanogen halides (CNX) and halonitromethanes (HNMs) – has proliferated. This is partly due to their high reported toxicity of N-DBPs. In this review paper information about the formation yields of N-DBPs from model precursors, and about environmental precursor occurrence, has been employed to assess the amount of N-DBP formation that is attributable to known precursors. It was calculated that for HANs and HAcAms, the concentrations of known precursors – mainly free amino acids are insufficient to account for the observed concentrations of these N-DBP groups. However, at least in some waters, a significant proportion of CNX and NDMA formation can be explained by known precursors. Identified N-DBP precursors tend to be of low molecular weight and low electrostatic charge relative to bulk natural organic matter (NOM). This makes them recalcitrant to removal by water treatment processes, notably coagulation, as confirmed by a number of bench-scale studies. However, amino acids have been found to be easier to remove during water treatment than would be suggested by the known molecular properties of the individual free amino acids.

  9. RNA precursor pool metabolism and RNA synthesis in X-irradiated Tetrahymena

    International Nuclear Information System (INIS)

    Stephens, R.E.; Paul, I.J.; Zimmerman, A.M.

    1976-01-01

    The incorporation of a radioactive RNA precursor ( 3 H-uridine) has been used in many studies as an index for measuring the synthesis of RNA, yet there is a distinct possibility that the results so obtained were significantly influenced by radiation-induced effects on the metabolism of this precursor into UTP (the primary immediate precursor of RNA) before its incorporation into RNA. A direct examination was therefore undertaken of the effects of X-irradiation on the metabolism of 3 H-uridine and its relationship to RNA synthesis as determined by incorporation. X-irradiation of logarithmically growing Tetrahymena pyriformis caused a dose-dependent depression of total cellular RNA synthesis. Ribosomal RNA (which comprises about 80 per cent of total cellular RNA) synthesis was also depressed by X-irradiation in a dose-dependent manner. Measurements of the levels of radioactivity present in the UTP precursor pool of both irradiated and unirradiated cells were obtained by means of DEAE-cellulose column chromatography of the extracted free nucleotides. Metabolism of 3 H-uridine into UMP, UDP and UTP was depressed by 40%, 26% and 27% respectively, whereas incorporation of 3 H-uridine into RNA was depressed by 77%. The results show that about one-third of the observed (apparent) depression in RNA synthesis was due to radiation-induced effects on the precursor pool, and the remaining two-thirds due to some definite effect of radiation at the transcription level leading to depressed synthesis of RNA. (U.K.)

  10. Identified EM Earthquake Precursors

    Science.gov (United States)

    Jones, Kenneth, II; Saxton, Patrick

    2014-05-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After a number of custom rock experiments, two hypotheses were formed which could answer the EM wave model. The first hypothesis concerned a sufficient and continuous electron movement either by surface or penetrative flow, and the second regarded a novel approach to radio transmission. Electron flow along fracture surfaces was determined to be inadequate in creating strong EM fields, because rock has a very high electrical resistance making it a high quality insulator. Penetrative flow could not be corroborated as well, because it was discovered that rock was absorbing and confining electrons to a very thin skin depth. Radio wave transmission and detection worked with every single test administered. This hypothesis was reviewed for propagating, long-wave generation with sufficient amplitude, and the capability of penetrating solid rock. Additionally, fracture spaces, either air or ion-filled, can facilitate this concept from great depths and allow for surficial detection. A few propagating precursor signals have been detected in the field occurring with associated phases using custom-built loop antennae. Field testing was conducted in Southern California from 2006-2011, and outside the NE Texas town of Timpson in February, 2013. The antennae have mobility and observations were noted for

  11. Los derechos de autor sobre obtenciones vegetales

    Directory of Open Access Journals (Sweden)

    Rosario Silva Gilli

    2015-01-01

    Full Text Available Contenido: Las creaciones en la agricultura. Los derechos de autor sobre obtenciones vegetales. El Convenio Internacional para la protección de las obtenciones vegetales (París 1961 y sus revisiones de Ginebra 1972, 1978,1991 Objeto de la protección legal. Condiciones del cultivar. Alcance de la protección. La protección de obtenciones vegetales en el Mercosur. Los Derechos de autor en el Mercosur. El Protocolo de Armonización de normas sobre Propiedad Intelectual en el Mercosur. El Acuerdo de Cooperación y facilitación sobre la protección de las obtenciones vegetales en los Estados Partes del Mercosur.  Alcance de la normativa Mercosur. Los Derechos sobre cultivares en Uruguay. Los Derechos de autor como derechos humanos. ¿Derechos de autor vs. derecho de propiedad intelectual? Reflexión final

  12. Identification of early B cell precursors (stage 1 and 2 hematogones) in the peripheral blood.

    Science.gov (United States)

    Kurzer, Jason H; Weinberg, Olga K

    2018-05-25

    Differentiating malignant B-lymphoblasts from early benign B cell precursors (hematogones) is a vital component of the diagnosis of B-lymphoblastic leukaemia. It has been previously reported that only late-stage B cell precursors circulate in the peripheral blood. Consequently, flow cytometric detection of cells with immunophenotypic findings similar to earlier stage precursors in the peripheral blood justifiably raises concern for involvement by B-lymphoblastic leukaemia. We report here, however, that benign early B cell precursors can indeed be detected in the peripheral blood, thus complicating the interpretation of flow cytometric findings derived from these sample types. A retrospective search of our collective databases identified 13 cases containing circulating early stage B cell precursors. The patients ranged in age from 15 days to 85 years old. All positive cases demonstrated that the earlier B cell precursors were associated with later stage precursors, a finding that could help differentiate these cells from B-lymphoblastic leukaemia. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Spinel formation for stabilizing simulated nickel-laden sludge with aluminum-rich ceramic precursors.

    Science.gov (United States)

    Shih, Kaimin; White, Tim; Leckie, James O

    2006-08-15

    The feasibility of stabilizing nickel-laden sludge from commonly available Al-rich ceramic precursors was investigated and accomplished with high nickel incorporation efficiency. To simulate the process, nickel oxide was mixed alternatively with gamma-alumina, corundum, kaolinite, and mullite and was sintered from 800 to 1480 degrees C. The nickel aluminate spinel (NiAl2O4) was confirmed as the stabilization phase for nickel and crystallized with efficiencies greater than 90% for all precursors above 1250 degrees C and 3-h sintering. The nickel-incorporation reaction pathways with these precursors were identified, and the microstructure and spinel yield were investigated as a function of sintering temperature with fixed sintering time. This study has demonstrated a promising process for forming nickel spinel to stabilize nickel-laden sludge from a wide range of inexpensive ceramic precursors, which may provide an avenue for economically blending waste metal sludges via the building industry processes to reduce the environmental hazards of toxic metals. The correlation of product textures and nickel incorporation efficiencies through selection of different precursors also provides the option of tailoring property-specific products.

  14. Catalytic Hydrodechlorination of Trichlorobenzenes with Pd(PhenCl2 as Catalyst Precursor

    Directory of Open Access Journals (Sweden)

    Guanlin Zhang

    2015-01-01

    Full Text Available We reported the catalytic hydrodechlorination (HDC of trichlorobenzenes by an organometallic compound Pd(PhenCl2 as a catalyst precursor. The catalyst precursor was prepared by chemical coordination reaction and characterized by FTIR and 1H NMR techniques. The HDC performance of Pd(PhenCl2 as catalyst precursor was evaluated on 1,2,3-, 1,2,4-, and 1,3,5-trichlorobenzenes (TCBs. All TCBs could be converted to dechlorination products with high conversion. Products distribution was closely related with the substrate structures and C-Cl bond energies. A reasonable reaction mechanism was also proposed.

  15. Thermogravimetric evaluation of the suitability of precursors for MOCVD

    International Nuclear Information System (INIS)

    Kunte, G V; Shivashankar, S A; Umarji, A M

    2008-01-01

    A method based on the Langmuir equation for the estimation of vapour pressure and enthalpy of sublimation of subliming compounds is described. The variable temperature thermogravimetric/differential thermogravimetric (TG/DTG) curve of benzoic acid is used to arrive at the instrument parameters. Employing these parameters, the vapour pressure–temperature curves are derived for salicylic acid and camphor from their TG/DTG curves. The values match well with vapour pressure data in the literature, obtained by effusion methods. By employing the Clausius–Clapeyron equation, the enthalpy of sublimation could be calculated. Extending the method further, two precursors for metal-organic chemical vapour deposition (MOCVD) of titanium oxide bis-isopropyl bis tert-butyl 2-oxobutanoato titanium, Ti(O i Pr) 2 (tbob) 2 , and bis-oxo-bis-tertbutyl 2-oxobutanoato titanium, [TiO(tbob) 2 ] 2 , have been evaluated. The complex Ti(O i Pr) 2 (tbob) 2 is found to be a more suitable precursor. This approach can be helpful in quickly screening for the suitability of a compound as a CVD precursor

  16. Spectroscopy Study of Synthetic Forsterite Obtained from Zeolite Precursors

    Directory of Open Access Journals (Sweden)

    Subotić, B.

    2008-02-01

    Full Text Available Important ceramics materials are prepared from aluminosilicate based precursors using novel methods, offering at the same time a better control over many important properties. Forsterite, due to its good refractoriness with melting point at 2163 K, excellent electrical insulation properties even at high temperatures, low dielectric permittivity, thermal expansion and chemical stability, is a material of interest to engineers and designers especially as an active medium for tuneable laser and is also a material of interest to SOFC (Solid oxide fuel cells manufacturers. The aim of this study is to investigate the synthesis of crystalline forsterite using different zeolite precursors previously activated by ball milling. Synthetic forsterite was synthesized from different zeolite precursors and MgO combining highenergy ball milling and thermal treatment of the mixture under determined conditions of time and temperature for each operation. In this research are studied the solid-state phase transformations taking place at temperatures below 1273 K. The obtained products were characterized using different spectroscopy techniques in comparison with surface analysis method and X-ray diffraction.

  17. Deposition of nanostructured photocatalytic zinc ferrite films using solution precursor plasma spraying

    International Nuclear Information System (INIS)

    Dom, Rekha; Sivakumar, G.; Hebalkar, Neha Y.; Joshi, Shrikant V.; Borse, Pramod H.

    2012-01-01

    Highlights: ► Highly economic solution precursor route capable of producing films/coating even for mass scale production. ► Pure spinel phase ZnFe 2 O 4 porous, immobilized films deposited in single step. ► Parameter optimization yields access to nanostructuring in SPPS method. ► The ecofriendly immobilized ferrite films were active under solar radiation. ► Such magnetic system display advantage w.r.t. recyclability after photocatalyst extraction. -- Abstract: Deposition of pure spinel phase, photocatalytic zinc ferrite films on SS-304 substrates by solution precursor plasma spraying (SPPS) has been demonstrated for the first time. Deposition parameters such as precursor solution pH, concentration, film thickness, plasma power and gun-substrate distance were found to control physico-chemical properties of the film, with respect to their crystallinity, phase purity, and morphology. Alkaline precursor conditions (7 2 O 4 film. Very high/low precursor concentrations yielded mixed phase, less adherent, and highly inhomogeneous thin films. Desired spinel phase was achieved in as-deposited condition under appropriately controlled spray conditions and exhibited a band gap of ∼1.9 eV. The highly porous nature of the films favored its photocatalytic performance as indicated by methylene blue de-coloration under solar radiation. These immobilized films display good potential for visible light photocatalytic applications.

  18. Bound volatile precursors in genotypes in the pedigree of 'Marion' blackberry (Rubus sp.).

    Science.gov (United States)

    Du, Xiaofen; Finn, Chad E; Qian, Michael C

    2010-03-24

    Glycosidically bound volatiles and precursors in genotypes representing the pedigree for 'Marion' blackberry were investigated over two growing seasons. The volatile precursors were isolated using a C18 solid-phase extraction column. After enzymatic hydrolysis, the released volatiles were analyzed using stir bar sorptive extraction gas chromatography-mass spectrometry (GC-MS) and direct microvial insert thermal desorption GC-MS. The most abundant volatile precursors in the genotypes were alcohols, followed by shikimic acid derivatives. High amounts of furanone glycosides were also detected, while norisoprenoids only existed in a small amount in blackberries. The volatile precursor composition in the genotypes in the 'Marion' pedigree was very similar to their free volatile distribution. 'Logan' and 'Olallie' predominantly had bound norisoprenoids. Wild 'Himalaya' predominated with terpene alcohol and furaneol glycosides, whereas 'Santiam' and 'Chehalem' contained a high level of terpene alcohol glycosides. A similar inheritance pattern was also observed for some volatile precursors in the genotypes in the 'Marion' pedigree. A high content of linalool, hydroxylinalool, and alpha-ionol glycosides in 'Olallie' and a low content in 'Chehalem' resulted in a moderate level in their offspring 'Marion', while a low content of (E)-linalool oxide precursor in 'Olallie' and a high content in 'Chehalem' also resulted in a moderate level in 'Marion'. However, the concentration of furaneol glycosides in 'Marion' exceeded that of its two parents.

  19. Ensaios sobre economia do empreendorismo

    OpenAIRE

    Gabrielito Rauter Menezes

    2015-01-01

    Esta tese é composta por três ensaios sobre Economia do Empreendedorismo. O primeiro deles trata sobre os determinantes do empreendedorismo no Brasil a partir de modelos de escolha ocupacional, usando os microdados da Pesquisa Nacional por Amostra por Domicílios (PNAD) do ano de 2012. A estratégia empírica adotada empregou os modelos de escolha discreta na estimação da escolha ocupacional. Os resultados demonstraram que existem efeitos significativos para as variáveis: anos de estudos iniciai...

  20. Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins.

    Science.gov (United States)

    Beita-Sandí, Wilson; Karanfil, Tanju

    2017-11-01

    Drinking water utilities are relying more than ever on water sources impacted by wastewater effluents. Disinfection/oxidation of these waters during water treatment may lead to the formation of several disinfection by-products, including the probable human carcinogen N-nitrosodimethylamine (NDMA) and the regulated trihalomethanes (THMs). In this study, the potential of ion exchange resins to control both NDMA and THMs precursors in a single treatment is presented. Two ion exchange resins were examined, a cation exchange resin (Plus) to target NDMA precursors and an anion exchange resin (MIEX) for THMs precursors control. We applied the resins, individually and combined, in the treatment of surface and wastewater effluent samples. The treatment with both resins removed simultaneously NDMA (43-85%) and THMs (39-65%) precursors. However, no removal of NDMA precursors was observed in the surface water with low initial NDMA FP (14 ng/L). The removals of NDMA FP and THMs FP with Plus and MIEX resins applied alone were (49-90%) and (41-69%), respectively. These results suggest no interaction between the resins, and thus the feasibility of effectively controlling NDMA and THMs precursors concomitantly. Additionally, the effects of the wastewater impact and the natural attenuation of precursors were studied. The results showed that neither the wastewater content nor the attenuation of the precursor affected the removals of NDMA and THMs precursors. Finally, experiments using a wastewater effluent sample showed that an increase in the calcium concentration resulted in a reduction in the removal of NDMA precursors of about 50%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Analytical control of the synthesis of the trithio and its precursors by gas chromatography; Control por cromatografia en fase gaseosa de la sintesis del trithion y de sus precursores

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Moreno, M. P.; Perez Garcia, M. M.; Angoso Marina, M.

    1979-07-01

    The synthesis of pesticide Trithio and its precursors has been controlled by G.L. selecting the best separation conditions and responses. The following columns have been used: 20% FFAP on chromo sorb W (a.w.) D.M.C.S. for organophosphate precursor glass column of 5 % Silicone SE-30 on chromo sorb G (a.w.) D.H.C.S. for S-(p-chlorophenyl-chloro methyl) and 12 % Silicone SE-30 modified with 8 % of Neopentyl-glicolsuccinate for Trithio. The relative retention times, retention indices and relative responses for. Trithio and its precursors have been calculated. (Author) 9 refs.

  2. Method to determine the sticking coefficient of precursor molecules in atomic layer deposition

    International Nuclear Information System (INIS)

    Rose, M.; Bartha, J.W.

    2009-01-01

    A method to determine the sticking coefficient of precursor molecules used in atomic layer deposition (ALD) will be introduced. The sticking coefficient is an interesting quantity for comparing different ALD processes and reactors but it cannot be observed easily. The method relies on free molecular flow in nanoscale cylindrical holes. The sticking coefficient is determined for tetrakis(dimethylamino)titanium in combination with ozone. The proposed method can be applied independent of the type of reactor, precursor delivery system and precursors.

  3. Combined effect of carcinogenic n-nitrosodimethylamine precursors and fractioned γ-irradiation on tumor development in rats

    International Nuclear Information System (INIS)

    Galenko, P.M.; Nedopitanskaya, N.N.

    1996-01-01

    The influence of combined action of N-nitrosodimethylamine (NDMA) and fractioned γ-irradiation on tumor development in rats was investigated. Both the tumor frequency and tumor plurality coefficient have been studied for two types of treatment: precursors of NDMA (amidopyrine and/or sodium nitrite (SN)) alone and the combination 'precursors plus radiation'. Tumor frequency decreased by about 11% after combination of γ-irradiation and precursors in comparison with precursors alone. Nevertheless, treatment with SN and γ-irradiation did not change tumor frequency in comparison with SN alone. Irradiation of rats treated with precursors led to an increased tumor plurality coefficient

  4. Formation of TiC/Al{sub 2}O{sub 3} composites from metal-polymer-precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jost, H.; Braun, M.; Staedler, C. [Technische Univ. Berlin (Germany). Inst. fuer Nichtmetallische Werkstoffe

    2002-07-01

    A new synthesis route for TiC/Al{sub 2}O{sub 3} materials was developed starting from a mixed metal-polymer precursor. The Precursor was prepared from aluminium nitrate, titantetrachloride and polymethacrylic acid dissolved in a solvent in order to achieve a high homogeneity of the precursor reactants. (orig.)

  5. The theory of planned behavior: Precursors of marijuana use in early adolescence?

    NARCIS (Netherlands)

    Malmberg, M.; Overbeek, G.J.; Vermulst, A.A.; Monshouwer, K.; Vollebergh, W.A.M.; Engels, R.C.M.E.

    2012-01-01

    Background: Precursors of marijuana use in early adolescence are largely unknown because studies generally focus on marijuana use among older adolescents or adults. Methods: In this study, we examined precursors of marijuana use in a sample of 1023 Dutch early adolescents (aged 11-14 at Time 1) who

  6. Laser microdissection of sensory organ precursor cells of Drosophila microchaetes.

    Directory of Open Access Journals (Sweden)

    Eulalie Buffin

    Full Text Available BACKGROUND: In Drosophila, each external sensory organ originates from the division of a unique precursor cell (the sensory organ precursor cell or SOP. Each SOP is specified from a cluster of equivalent cells, called a proneural cluster, all of them competent to become SOP. Although, it is well known how SOP cells are selected from proneural clusters, little is known about the downstream genes that are regulated during SOP fate specification. METHODOLOGY/PRINCIPAL FINDINGS: In order to better understand the mechanism involved in the specification of these precursor cells, we combined laser microdissection, toisolate SOP cells, with transcriptome analysis, to study their RNA profile. Using this procedure, we found that genes that exhibit a 2-fold or greater expression in SOPs versus epithelial cells were mainly associated with Gene Ontology (GO terms related with cell fate determination and sensory organ specification. Furthermore, we found that several genes such as pebbled/hindsight, scabrous, miranda, senseless, or cut, known to be expressed in SOP cells by independent procedures, are particularly detected in laser microdissected SOP cells rather than in epithelial cells. CONCLUSIONS/SIGNIFICANCE: These results confirm the feasibility and the specificity of our laser microdissection based procedure. We anticipate that this analysis will give new insight into the selection and specification of neural precursor cells.

  7. [Study on Precursors for Synthesis of Anthraquinone Metabolites from Rheum tanguticum].

    Science.gov (United States)

    Hasi, Qi-mei-ge; Lj, Hai-ling; Cheng, Yan; Menggen, Qi-qi-ge; Zhang, Yang

    2015-01-01

    To explore the potential precursors of the anthraquinone metabolites from Rheum tanguticum and preliminanly identify the synthesis pathway thereof. Sterile seedlings sprouted from the seeds of Rheum tanguticum were chosen as materials for inducing callus. The effects of different precursors and feeding duration on the callus of Rheum tanguticum and the anthraquinone yield in adult rheum were studied. The greatest improvement of anthraquinone yield was achieved by acetic acid, increasing 43. 9% for the callus and 45. 8% in the adult rheum; the second greatest improvement was achieved by malonic acid, increasing 15. 8% for the callus and only 3. 6% in the adult rheum. The yield of anthraquinone was not influenced significantly by benzoic acid and p-benzoquinone, and in contrast, was inhibited in some degree by shikimic acid and α-ketoglutaric acid. A suitable feeding duration was 36 h, which worked well for the effects of precursors. The precursor for synthesis of anthraquinone metabolites from Rheum tan- guticum is acetic acid, which improves the yields of callus and anthraquinone in adult rheum, concluding that the anthraquinone metabolites are synthesized via polyketone pathway.

  8. Statistical study of spatio-temporal distribution of precursor solar flares associated with major flares

    Science.gov (United States)

    Gyenge, N.; Ballai, I.; Baranyi, T.

    2016-07-01

    The aim of the present investigation is to study the spatio-temporal distribution of precursor flares during the 24 h interval preceding M- and X-class major flares and the evolution of follower flares. Information on associated (precursor and follower) flares is provided by Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Flare list, while the major flares are observed by the Geostationary Operational Environmental Satellite (GOES) system satellites between 2002 and 2014. There are distinct evolutionary differences between the spatio-temporal distributions of associated flares in about one-day period depending on the type of the main flare. The spatial distribution was characterized by the normalized frequency distribution of the quantity δ (the distance between the major flare and its precursor flare normalized by the sunspot group diameter) in four 6 h time intervals before the major event. The precursors of X-class flares have a double-peaked spatial distribution for more than half a day prior to the major flare, but it changes to a lognormal-like distribution roughly 6 h prior to the event. The precursors of M-class flares show lognormal-like distribution in each 6 h subinterval. The most frequent sites of the precursors in the active region are within a distance of about 0.1 diameter of sunspot group from the site of the major flare in each case. Our investigation shows that the build-up of energy is more effective than the release of energy because of precursors.

  9. Versatile High-Performance Regenerated Cellulose Membranes Prepared using Trimethylsilyl Cellulose as a Precursor

    KAUST Repository

    Puspasari, Tiara

    2018-01-01

    (TMSC), a highly soluble cellulose derivative, as a precursor for the fabrication of cellulose thin film composite membranes. TMSC is an attractive precursor to assemble thin cellulose films with good deposition behavior and film morphology; cumbersome

  10. Seismic-electromagnetic precursors of Romania's Vrancea earthquakes

    International Nuclear Information System (INIS)

    Enescu, B.D.; Enescu, C.; Constantin, A. P.

    1999-01-01

    Diagrams were plotted from electromagnetic data that were recorded at Muntele Rosu Observatory during December 1996 to January 1997, and December 1997 to September 1998. The times when Vrancea earthquakes of magnitudes M ≥ 3.9 occurred within these periods are marked on the diagrams.The parameters of the earthquakes are given in a table which also includes information on the magnetic and electric anomalies (perturbations) preceding these earthquakes. The magnetic data prove that Vrancea earthquakes are preceded by magnetic perturbations that may be regarded as their short-term precursors. Perturbations, which could likewise be seen as short-term precursors of Vrancea earthquakes, are also noticed in the electric records. Still, a number of electric data do cast a doubt on their forerunning nature. Some suggestions are made in the end of the paper on how electromagnetic research should go ahead to be of use for Vrancea earthquake prediction. (authors)

  11. Precursors to potential severe core damage accidents: 1994, a status report. Volume 22: Appendix I

    International Nuclear Information System (INIS)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Vanden Heuvel, L.N.; Dolan, B.W.; Minarick, J.W.

    1995-12-01

    Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1

  12. Precursors to potential severe core damage accidents: 1994, a status report. Volume 22: Appendix I

    Energy Technology Data Exchange (ETDEWEB)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Vanden Heuvel, L.N. [Oak Ridge National Lab., TN (United States); Dolan, B.W.; Minarick, J.W. [Oak Ridge National Lab., TN (United States)]|[Science Applications International Corp., Oak Ridge, TN (United States)

    1995-12-01

    Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 {times} 10{sup {minus}6}. These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1.

  13. Method for the preparation of carbon fiber from polyolefin fiber precursor

    Energy Technology Data Exchange (ETDEWEB)

    Naskar, Amit Kumar; Hunt, Marcus Andrew; Saito, Tomonori

    2017-11-28

    Methods for the preparation of carbon fiber from polyolefin fiber precursor, wherein the polyolefin fiber precursor is partially sulfonated and then carbonized to produce carbon fiber. Methods for producing hollow carbon fibers, wherein the hollow core is circular- or complex-shaped, are also described. Methods for producing carbon fibers possessing a circular- or complex-shaped outer surface, which may be solid or hollow, are also described.

  14. CXCR6 Expression Is Important for Retention and Circulation of ILC Precursors

    Directory of Open Access Journals (Sweden)

    Sylvestre Chea

    2015-01-01

    Full Text Available Innate lymphoid cells are present at mucosal sites and represent the first immune barrier against infections, but what contributes to their circulation and homing is still unclear. Using Rag2−/−Cxcr6Gfp/+ reporter mice, we assessed the expression and role of CXCR6 in the circulation of ILC precursors and their progeny. We identify CXCR6 expressing ILC precursors in the bone marrow and characterize their significant increase in CXCR6-deficient mice at steady state, indicating their partial retention in the bone marrow after CXCR6 ablation. Circulation was also impaired during embryonic life as fetal liver from CXCR6-deficient embryos displayed decreased numbers of ILC3 precursors. When injected, fetal CXCR6-deficient ILC3 precursors also fail to home and reconstitute ILC compartments in vivo. We show that adult intestinal ILC subsets have heterogeneous expression pattern of CXCR6, integrin α4β7, CD62L, CD69, and CD44, with ILC1 and ILC3 being more likely tissue resident lymphocytes. Intestinal ILC subsets were unchanged in percentages and numbers in both mice. We demonstrate that the ILC frequency is maintained due to a significant increase of ILC peripheral proliferation, as well as an increased proliferation of the in situ ILC precursors to compensate their retention in the bone marrow.

  15. Relationship between organic precursors and N-nitrosodimethylamine (NDMA) formation in tropical water sources.

    Science.gov (United States)

    Qi, Wang; Fang Yee, Lim; Jiangyong, Hu

    2014-12-01

    The presence of organic compounds in water sources is one of the concerns in water treatment. They are potential precursors of disinfection byproducts (DBPs) and thus induce health problems in humans. Among the emerging DBPs, carcinogenic compound N-nitrosodimethylamine (NDMA) has been receiving attention during the last decade. This study examined the characteristics of organic components in various water sources and investigated their relationships with NDMA formation. Experiments were carried out on selected water samples from both natural water and wastewater. Results showed similar NDMA formation kinetics for both water sources. However, more contribution of NDMA precursors was found to be from the wastewater due to its higher organic nitrogen content. NDMA formation potential (NDMAFP) of secondary effluent ranged from 264 to 530 ng/L. A correlation study between organic compound characteristics and NDMAFP indicated that the majority of NDMA precursors came from dissolved organic nitrogen (DON) compound with small molecular weight (smaller than 500 Da), with correlation R(2) = 0.898. Although secondary treatment removed more than 90% of NDMA precursors, the remaining precursors in secondary effluent would still pose a challenge for water quality.

  16. Hydrodeoxygenation of O-containing polycyclic model compounds using a novel organometallic catalyst-precursor

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, S.R.; Song, C.S.; Schobert, H.H. [Pennsylvania State University, University Park, PA (United States). Dept. of Materials Science and Engineering

    1996-09-05

    Compounds containing oxygen functional groups, especially phenols, are undesirable components of coal-derived liquids. Removal of these compounds from the products of coal liquefaction is required. A beneficial alternative would be the removal of these compounds, or the prevention of their formation, during the liquefaction reaction itself, rather than as a separate processing step. A novel organometallic catalyst precursor containing Co and Mo has been studied as a potential hydrogenation catalyst for coal liquefaction. To ascertain the hydrodeoxygenation activity of this catalyst under liquefaction conditions, model compounds were investigated. Anthrone, 2,6-di-r-btuyl-4-methyl-phenol, dinaphthyl ether and xanthene were reacted in the presence of the Co-Mo catalyst precursor and a precursor containing only Mo over a range of temperatures, providing a comparison of conversions to deoxygenated products. These conversions give an indication of the hydrodeoxygenating abilities of organometallic catalyst precursors within a coal liquefaction system. For example, at 400{degree}C dinaphthyl ether was converted 100% (4.5% O-containing products) in the presence of the Co-Mo organometallic precursor, compared to 76.5% conversion (7.4% O-products) in the presence of the Mo catalyst.

  17. Synaptic network activity induces neuronal differentiation of adult hippocampal precursor cells through BDNF signaling

    Directory of Open Access Journals (Sweden)

    Harish Babu

    2009-09-01

    Full Text Available Adult hippocampal neurogenesis is regulated by activity. But how do neural precursor cells in the hippocampus respond to surrounding network activity and translate increased neural activity into a developmental program? Here we show that long-term potential (LTP-like synaptic activity within a cellular network of mature hippocampal neurons promotes neuronal differentiation of newly generated cells. In co-cultures of precursor cells with primary hippocampal neurons, LTP-like synaptic plasticity induced by addition of glycine in Mg2+-free media for 5 min, produced synchronous network activity and subsequently increased synaptic strength between neurons. Furthermore, this synchronous network activity led to a significant increase in neuronal differentiation from the co-cultured neural precursor cells. When applied directly to precursor cells, glycine and Mg2+-free solution did not induce neuronal differentiation. Synaptic plasticity-induced neuronal differentiation of precursor cells was observed in the presence of GABAergic neurotransmission blockers but was dependent on NMDA-mediated Ca2+ influx. Most importantly, neuronal differentiation required the release of brain-derived neurotrophic factor (BDNF from the underlying substrate hippocampal neurons as well as TrkB receptor phosphorylation in precursor cells. This suggests that activity-dependent stem cell differentiation within the hippocampal network is mediated via synaptically evoked BDNF signaling.

  18. Financial risk relationships and adoption of management strategies in physician groups for self-administered injectable drugs.

    Science.gov (United States)

    Agnew, Jonathan D; Stebbins, Marilyn R; Hickman, David E; Lipton, Helene Levins

    2003-01-01

    To consider the extent, nature, and range of risk arrangements between physician groups and health maintenance organizations (HMOs) for self-administered injectable (SAI) drugs; to examine types and frequencies of SAI drug-use management strategies adopted by physician groups; and to explore the relationship between locus and level of financial risk for SAIs and physician group strategy adoption. We used a multiple case-study design to select physician groups and their health maintenance organization (HMO) contractual partners in 4 markets in the United States (Northwest, Northeast, Midwest, Southwest). Physician groups in these markets were chosen based on size (e50 physicians) and experience with drug risk (e1 year). Physician groups were asked to identify their 3 major HMO contractual partners in each market. Telephone interviews were conducted from January 2000 to June 2001, with the resulting purposive sample of 37 individuals representing 20 physician groups. We found that the level and locus of SAI financial risk were related to the adoption of management strategies. Physician groups with higher financial risk for SAIs adopted more strategies than lower-risk groups. Groups with SAI financial risk in the medical services capitation (MSC) adopted 9.2 strategies per group. In contrast, groups with SAI financial risk in the pharmacy-risk budget (PRB) averaged 1.5 strategies per group. Groups with SAI financial risk in both the MSC and PRB fell in-between, averaging 4.5 strategies per group. The most frequently adopted strategy was designing evidenced-based therapeutic guidelines, i.e., protocols based on evidence from the peer-reviewed literature used to guide physicians in the treatment of typically chronic conditions (9 groups, 45% of sample). The second most common strategy involved adapting the existing utilization management system to process SAIs (7 groups, 35%) and the establishment of office procedures for internal authorization (5 groups, 25%). The

  19. New Ir Bis-Carbonyl Precursor for Water Oxidation Catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Daria L. [Department of Chemistry, Yale University, 225; Beltrán-Suito, Rodrigo [Department of Chemistry, Yale University, 225; Thomsen, Julianne M. [Department of Chemistry, Yale University, 225; Hashmi, Sara M. [Department of Chemical and Environmental; Materna, Kelly L. [Department of Chemistry, Yale University, 225; Sheehan, Stafford W. [Catalytic Innovations LLC, 70 Crandall; Mercado, Brandon Q. [Department of Chemistry, Yale University, 225; Brudvig, Gary W. [Department of Chemistry, Yale University, 225; Crabtree, Robert H. [Department of Chemistry, Yale University, 225

    2016-02-05

    This paper introduces IrI(CO)2(pyalc) (pyalc = (2-pyridyl)-2-propanoate) as an atom-efficient precursor for Ir-based homogeneous oxidation catalysis. This compound was chosen to simplify analysis of the water oxidation catalyst species formed by the previously reported Cp*IrIII(pyalc)OH water oxidation precatalyst. Here, we present a comparative study on the chemical and catalytic properties of these two precursors. Previous studies show that oxidative activation of Cp*Ir-based precursors with NaIO4 results in formation of a blue IrIV species. This activation is concomitant with the loss of the placeholder Cp* ligand which oxidatively degrades to form acetic acid, iodate, and other obligatory byproducts. The activation process requires substantial amounts of primary oxidant, and the degradation products complicate analysis of the resulting IrIV species. The species formed from oxidation of the Ir(CO)2(pyalc) precursor, on the other hand, lacks these degradation products (the CO ligands are easily lost upon oxidation) which allows for more detailed examination of the resulting Ir(pyalc) active species both catalytically and spectroscopically, although complete structural analysis is still elusive. Once Ir(CO)2(pyalc) is activated, the system requires acetic acid or acetate to prevent the formation of nanoparticles. Investigation of the activated bis-carbonyl complex also suggests several Ir(pyalc) isomers may exist in solution. By 1H NMR, activated Ir(CO)2(pyalc) has fewer isomers than activated Cp*Ir complexes, allowing for advanced characterization. Future research in this direction is expected to contribute to a better structural understanding of the active species. A diol crystallization agent was needed for the structure determination of 3.

  20. Recursos y enlaces sobre comunidades de aprendizaje

    OpenAIRE

    Ferrer Esteban, Gerard

    2005-01-01

    Obras y artículos sobre el proyecto Comunidades de Aprendizaje desarrollado en el Estado español. Tesis doctorales sobre comunidades de aprendizaje. Fundamentación teórica de las comunidades de aprendizaje. Sitios en Internet relacionados con las comunidades de aprendizaje y proyectos afines de desarrollo comunitario en contextos escolares.

  1. Vaporization of a mixed precursors in chemical vapor deposition for YBCO films

    Science.gov (United States)

    Zhou, Gang; Meng, Guangyao; Schneider, Roger L.; Sarma, Bimal K.; Levy, Moises

    1995-01-01

    Single phase YBa2Cu3O7-delta thin films with T(c) values around 90 K are readily obtained by using a single source chemical vapor deposition technique with a normal precursor mass transport. The quality of the films is controlled by adjusting the carrier gas flow rate and the precursor feed rate.

  2. Investigations on precursor measures for aeroelastic flutter

    Science.gov (United States)

    Venkatramani, J.; Sarkar, Sunetra; Gupta, Sayan

    2018-04-01

    Wind tunnel experiments carried out on a pitch-plunge aeroelastic system in the presence of fluctuating flows reveal that flutter instability is presaged by a regime of intermittency. It is observed that as the flow speed gradually increases towards the flutter speed, there appears intermittent bursts of periodic oscillations which become more frequent as the wind speed increases and eventually the dynamics transition into fully developed limit cycle oscillations, marking the onset of flutter. The signature from these intermittent oscillations are exploited to develop measures that forewarn a transition to flutter and can serve as precursors. This study investigates a suite of measures that are obtained directly from the time history of measurements and are hence model independent. The dependence of these precursors on the size of the measured data set and the time required for their computation is investigated. These measures can be useful in structural health monitoring of aeroelastic structures.

  3. Boron nitride ceramics from molecular precursors: synthesis, properties and applications.

    Science.gov (United States)

    Bernard, Samuel; Salameh, Chrystelle; Miele, Philippe

    2016-01-21

    Hexagonal boron nitride (h-BN) attracts considerable interest because its structure is similar to that of carbon graphite while it displays different properties which are of interest for environmental and green technologies. The polar nature of the B-N bond in sp(2)-bonded BN makes it a wide band gap insulator with different chemistry on its surface and particular physical and chemical properties such as a high thermal conductivity, a high temperature stability, a high resistance to corrosion and oxidation and a strong UV emission. It is chemically inert and nontoxic and has good environmental compatibility. h-BN also has enhanced physisorption properties due to the dipolar fields near its surface. Such properties are closely dependent on the processing method. Bottom-up approaches consist of transforming molecular precursors into non-oxide ceramics with retention of the structural units inherent to the precursor molecule. The purpose of the present review is to give an up-to-date overview on the most recent achievements in the preparation of h-BN from borazine-based molecular single-source precursors including borazine and 2,4,6-trichloroborazine through both vapor phase syntheses and methods in the liquid/solid state involving polymeric intermediates, called the Polymer-Derived Ceramics (PDCs) route. In particular, the effect of the chemistry, composition and architecture of the borazine-based precursors and derived polymers on the shaping ability as well as the properties of h-BN is particularly highlighted.

  4. Ghrelin precursor gene polymorphism and methamphetamine dependence in the Korean population.

    Science.gov (United States)

    Yoon, Su-Jung; Pae, Chi-Un; Lee, Heejin; Choi, Bomoon; Kim, Tae-Suk; Lyoo, In Kyoon; Kwon, Do-Hoon; Kim, Dai-Jin

    2005-12-01

    Ghrelin is a recently isolated brain-gut peptide that has growth hormone-releasing and appetite-inducing activities. Several recent studies have suggested that ghrelin plays a major role in the pathophysiology of drug-seeking behavior and anxiety. Therefore, we assessed the effect of the ghrelin precursor polymorphism on methamphetamine dependence in the Korean population. One hundred and eighteen patients with methamphetamine dependence, according to the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria, and the 144 healthy controls were enrolled in this study. Genotyping for the ghrelin precursor polymorphism was performed by the polymerase chain reaction-restriction fragment length polymorphism-based technique. The genotypic and allelic distributions of the ghrelin precursor polymorphism in the patients with methamphetamine dependence were not significantly different from those of the control subjects. However, the Met72 carriers were associated with the emotional problems of methamphetamine dependence. The patients with the Met72 allele were more depressed and anxious than the homozygous patients with the wild Leu72 allele. The present study suggests that the ghrelin precursor polymorphism may not confer a susceptibility to the development of methamphetamine dependence in the Korean population. However, the Leu72Met polymorphism could have a potential role in the emotional problems that are associated with this disease.

  5. Stable amorphous georgeite as a precursor to a high-activity catalyst

    Science.gov (United States)

    Kondrat, Simon A.; Smith, Paul J.; Wells, Peter P.; Chater, Philip A.; Carter, James H.; Morgan, David J.; Fiordaliso, Elisabetta M.; Wagner, Jakob B.; Davies, Thomas E.; Lu, Li; Bartley, Jonathan K.; Taylor, Stuart H.; Spencer, Michael S.; Kiely, Christopher J.; Kelly, Gordon J.; Park, Colin W.; Rosseinsky, Matthew J.; Hutchings, Graham J.

    2016-03-01

    Copper and zinc form an important group of hydroxycarbonate minerals that include zincian malachite, aurichalcite, rosasite and the exceptionally rare and unstable—and hence little known and largely ignored—georgeite. The first three of these minerals are widely used as catalyst precursors for the industrially important methanol-synthesis and low-temperature water-gas shift (LTS) reactions, with the choice of precursor phase strongly influencing the activity of the final catalyst. The preferred phase is usually zincian malachite. This is prepared by a co-precipitation method that involves the transient formation of georgeite; with few exceptions it uses sodium carbonate as the carbonate source, but this also introduces sodium ions—a potential catalyst poison. Here we show that supercritical antisolvent (SAS) precipitation using carbon dioxide (refs 13, 14), a process that exploits the high diffusion rates and solvation power of supercritical carbon dioxide to rapidly expand and supersaturate solutions, can be used to prepare copper/zinc hydroxycarbonate precursors with low sodium content. These include stable georgeite, which we find to be a precursor to highly active methanol-synthesis and superior LTS catalysts. Our findings highlight the value of advanced synthesis methods in accessing unusual mineral phases, and show that there is room for exploring improvements to established industrial catalysts.

  6. Manuel Larraín y la conciencia eclesial latinoamericana: Visión y legado de un precursor

    Directory of Open Access Journals (Sweden)

    Fernando Berríos

    2009-01-01

    Full Text Available Manuel Larraín Errázuriz, obispo de Talca, Chile, entre 1938 y 1966, es una de las principales figuras de la Iglesia latinoamericana del siglo XX y uno de los más importantes precursores del Concilio Vaticano II en este continente, sobre todo por su actitud de apertura a los desafíos y complejidades del mundo moderno desde una profunda fidelidad al Evangelio. El artículo busca destacar su aporte, en ese horizonte, a la conformación de una conciencia eclesial auténticamente latinoamericana. La primera parte es una presentación del catolicismo chileno tradicional en que él se formó y que más tarde se abriría a perspectivas más amplias por diversos influjos históricos. La segunda parte se refiere a cuatro grandes temas y circunstancias en los que Manuel Larraín jugó un destacado rol como pastor, forjando así esa conciencia eclesial que ha quedado como su principal legado. El texto concluye con una breve reflexión sobre este legado y sobre los desafíos que él plantea hasta hoy a la Iglesia del continente.Manuel Larraín Errázuriz, bishop of Talca, Chile, between 1938 and 1966, is one of the principal figures of the Latin American Church in the 20th century, and one of the most important forerunners of Vatican Council II on this continent, above all for the openness of his attitude while facing the challenges and complexities of the modern world from a position of deep faithfulness to the Gospel. This article seeks to emphasize his contribution, on that horizon, to the conformation of an authentically Latin American ecclesial consciousness. The first part of this article is a presentation of the traditional Chilean Catholicism in which he was brought up and which, later on, would open itself to wider perspectives thanks to different historical influences. The second part refers to four great themes and the circumstances in which Manuel Larraín played an important role as pastor, thus forging that ecclesial consciousness which

  7. Differentiation of Mouse Embryonic Stem Cells into Ventral Foregut Precursors

    DEFF Research Database (Denmark)

    Rothová, Michaela; Hölzenspies, Jurriaan J; Livigni, Alessandra

    2016-01-01

    Anterior definitive endoderm (ADE), the ventral foregut precursor, is both an important embryonic signaling center and a unique multipotent precursor of liver, pancreas, and other organs. Here, a method is described for the differentiation of mouse embryonic stem cells (mESCs) to definitive...... endoderm with pronounced anterior character. ADE-containing cultures can be produced in vitro by suspension (embryoid body) culture or in a serum-free adherent monolayer culture. ESC-derived ADE cells are committed to endodermal fates and can undergo further differentiation in vitro towards ventral foregut...

  8. The route of liquid precursor to ZnO nanoparticles in premixed combustion spray pyrolysis

    Science.gov (United States)

    Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2018-04-01

    Zinc oxide nanoparticles had been successfully synthesized by premixed combustion spray pyrolysis. Zinc acetate was dissolved in distilled water was selected as a liquid precursor. Zinc nitrate was also used for comparison the effect of precursor type on the generated particles morphology and the crystallinity. The premixed combustion reaction used liquefied petroleum gas (LPG) mainly consisting of butane and propane as a fuel and compressed air used as an oxidizer. The liquid precursor was atomized using a custom two fluid nozzle to generate droplets. Then, the droplets were sprayed by the flow of air as a carrier gas into the premixed combustion reactor. The zinc precursor was decomposed to zinc oxide due to the high temperature as a result of combustion reaction inside the reactor resulting in nanoparticles formation. The particle size decreased with the increase of the fuel flow rate. In addition, it can be found that at the same flow rate of fuel, the particle size of zinc oxide synthesized using zinc nitrate is larger than that of the use of zinc acetate as a precursor.

  9. Dry Process for Manufacturing Hybridized Boron Fiber/Carbon Fiber Thermoplastic Composite Materials from a Solution Coated Precursor

    Science.gov (United States)

    Belvin, Harry L. (Inventor); Cano, Roberto J. (Inventor)

    2003-01-01

    An apparatus for producing a hybrid boron reinforced polymer matrix composite from precursor tape and a linear array of boron fibers. The boron fibers are applied onto the precursor tapes and the precursor tape processed within a processing component having an impregnation bar assembly. After passing through variable-dimension forming nip-rollers, the precursor tape with the boron fibers becomes a hybrid boron reinforced polymer matrix composite. A driving mechanism is used to pulled the precursor tape through the method and a take-up spool is used to collect the formed hybrid boron reinforced polymer matrix composite.

  10. Methionine as a Precursor of Ethylene—Commentary

    Science.gov (United States)

    Lieberman et al. showed in a 1966 publication of Plant Physiology that methionine is a precursor of ethylene. It was the first paper that showed ethylene carbons are derived from carbons 3 and 4 of methionine. This paper catalyzed remarkable interest among plant biologists to elucidate the biosynth...

  11. FT-IR and 29 Si-NMR for evaluating aluminium silicate precursors for geopolymers

    NARCIS (Netherlands)

    Valcke, S.L.A.; Pipilikaki, P.; Fischer, H.R.; Verkuijlen, M.H.W.; Eck, E.R.H.

    2014-01-01

    Geopolymers are systems of inorganic binders that can be used for sustainable, cementless concrete and are formed by alkali activation of an aluminium–silicate precursor (often secondary resources like fly ash or slag). The type of aluminium– silicate precursor and its potential variations within

  12. Different radiosensitivities of mast-cell precursors in the bone marrow and skin of mice

    International Nuclear Information System (INIS)

    Kitamura, Y.; Yokoyama, M.; Sonoda, T.; Mori, K.J.

    1983-01-01

    Although tissue mast cells are derived from the bone marrow, some descendants of bone marrow-derived precursors retain the ability to proliferate and differentiate into mast cells even after localization in the skin. The purpose of the present study was to determine the D0 values for mast-cell precursors in the bone marrow and those localized in the skin. Bone marrow cells were removed from (WB X C57BL/6)F1-+/+ mice after various doses of irradiation and injected into the skin of the congenic W/Wv mice which were genetically without mast cells. Radiosensitivity of mast-cell precursors in the bone marrow was evaluated by determining the proportion of the injection sites at which mast cells did not appear. For the assay of the radiosensitivity of mast-cell precursors localized in the skin, pieces of skin were removed from beige C57BL/6 (bgJ/bgJ. Chediak-Higashi syndrome) mice after various doses of irradiation and grafted onto the back of the normal C57BL/6 mice. Radiosensitivity of mast-cell precursors in the skin was evaluated by determining the decrease of beige-type mast cells which possessed giant granules. Mast-cell precursors in the bone marrow were much more radiosensitive than those localized in the skin. D0 value was about 100 rad for the former and about 800 rad for the latter

  13. Titanium di-oxide films using a less hygroscopic colloidal precursor

    Energy Technology Data Exchange (ETDEWEB)

    Vandana,, E-mail: vandana1@nplindia.org; Batra, Neha; Kumar, Praveen; Sharma, Pooja; Singh, P.K., E-mail: pksingh@nplindia.org

    2014-04-01

    We report the study of titanium dioxide films (TiO{sub 2}) using titanium di-isopropoxyl di-2ethyl hexanoate Ti(OC{sub 3}H{sub 7}){sub 2} (C{sub 7}H{sub 15}COO){sub 2} colloidal precursor. This compound is less hygroscopic in nature and easy to use with processes like spin or dip coating. Thin films of TiO{sub 2} are made on silicon substrates and their structural and optical properties are studied. The effect of Ti content in the precursor, sintering temperature and its duration on film thickness and refractive index are investigated. Refractive index shows an increasing trend with the rise in the sintering temperature but remains unchanged with the time. The film thickness decreases with both sintering temperature and time and increases with Ti content in the precursor. Reflectivity measurements show marked reduction in the reflection losses compared to bare silicon surface wherein the film thickness is altered by spin speed. XRD results show anatase phase in the samples sintered at lower temperature (<680 °C), however, a mix of anatase, brookite and rutile phases is seen above this temperature. In the samples sintered above 1100 °C, rutile phase is dominant. These results are supported by the X-ray photoelectron spectroscopy. Atomic force microscopy reveals larger grain size at higher sintering temperature. The titanium dioxide films of desirable thickness and refractive index could be used as an antireflection coating on solar cells. - Highlights: • TiO{sub 2} films are made using titanium di-isopropoxyl di-2ethyl hexanoate precursor. • Effect of Ti content in the precursor, sintering temperature and time is studied. • Refractive index (μ) increases with sintering temperature but is independent of time. • Films of desired thickness and μ could be used as an antireflection coating. • XRD results show that rutile phase dominates in samples sintered above 1100 °C.

  14. Contribution of constitutively proliferating precursor cell subtypes to dentate neurogenesis after cortical infarcts

    Directory of Open Access Journals (Sweden)

    Oberland Julia

    2010-11-01

    Full Text Available Abstract Background It is well known that focal ischemia increases neurogenesis in the adult dentate gyrus of the hippocampal formation but the cellular mechanisms underlying this proliferative response are only poorly understood. We here investigated whether precursor cells which constitutively proliferate before the ischemic infarct contribute to post-ischemic neurogenesis. To this purpose, transgenic mice expressing green fluorescent protein (GFP under the control of the nestin promoter received repetitive injections of the proliferation marker bromodeoxyuridine (BrdU prior to induction of cortical infarcts. We then immunocytochemically analyzed the fate of these BrdU-positive precursor cell subtypes from day 4 to day 28 after the lesion. Results Quantification of BrdU-expressing precursor cell populations revealed no alteration in number of radial glia-like type 1 cells but a sequential increase of later precursor cell subtypes in lesioned animals (type 2a cells at day 7, type 3 cells/immature neurons at day 14. These alterations result in an enhanced survival of mature neurons 4 weeks postinfarct. Conclusions Focal cortical infarcts recruit dentate precursor cells generated already before the infarct and significantly contribute to an enhanced neurogenesis. Our findings thereby increase our understanding of the complex cellular mechanisms of postlesional neurogenesis.

  15. La ceguera como motivo en Ensayo sobre la ceguera de José Saramago e Informe sobre ciegos de Ernesto Sábato

    OpenAIRE

    Fonseca, Marco Antonio

    2008-01-01

    El trabajo de investigación, El motivo de la ceguera en el Ensayo sobre la ceguera de José Saramago e Informe sobre ciegos de Ernesto Sábato, analiza desde el área y la metodología de la literatura comparada el uso del motivo literario de la ceguera en los dos textos mencionados, resaltando las similitudes y diferencias del tratamiento del motivo dentro de las dos obras y como éste sostiene una serie de obsesiones e ideas sobre el estado actual del mundo que comparten los autores de las dos n...

  16. Bulk and Surface Structures of Palladium-Modified Copper-Zinc Oxides ex Hydroxycarbonate Precursors

    NARCIS (Netherlands)

    López Granados, M.; Melián-Cabrera, I.; Fierro, J.L.G.

    2002-01-01

    (Pd)-Cu-Zn ex hydroxycarbonate precursors were prepared and characterized by several bulk and surface techniques. A palladium-free Cu-Zn precursor (CZ) was prepared by coprecipitation. Two Pd-Cu-Zn samples were prepared by coprecipitation (PCZ-CP) and sequential precipitation (PCZ-SP). It is shown

  17. O DISCURSO OFICIAL SOBRE A CRIANÇA NO BRASIL

    Directory of Open Access Journals (Sweden)

    Carla Letuza Moreira e Silva

    2016-09-01

    Full Text Available Este estudo é um recorte da tese de doutoramento apresentada em 2012, no Programa de Pós-Graduação e Letras e Linguística da Universidade Federal de Alagoas (UFAL, em Maceió, sobre os discursos da/sobre a criança e as infâncias, no Brasil. O objetivo central é o de apresentar os efeitos de sentido que demandam dos dizeres oficiais no Estatuto da Criança e do Adolescente (ECA, 1990 em vigor no Brasil, sobre a criança, e que determinam modos de pensar e agir sobre as crianças e a infância na contemporaneidade. As noções de sujeito e formação discursiva da análise do discurso francesa (AD, iniciada em Pêcheux (1997, permeiam as análises e elucidam os papéis históricos e ideológicos que determinam e são determinados nos/pelos dizeres dos discursos da/sobre. Faz-se necessário, portanto, adentrar os discursos da e sobre a criança e a infância para entender as contradições e os confrontos dos discursos entre dizeres e silenciamentos.

  18. Degradation of Highly Alloyed Metal Halide Perovskite Precursor Inks: Mechanism and Storage Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Dou, Benjia [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wheeler, Lance M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Christians, Jeffrey A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Moore, David [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Harvey, Steven P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Berry, Joseph J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Van Hest, Marinus F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Barnes, Frank S. [University of Colorado; Shaheen, Sean E. [University of Colorado

    2018-03-02

    Whereas the promise of metal halide perovskite (MHP) photovoltaics (PV) is that they can combine high efficiency with solution-processability, the chemistry occurring in precursor inks is largely unexplored. Herein, we investigate the degradation of MHP solutions based on the most widely used solvents, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). For the MHP inks studied, which contain formamidinium (FA+), methylammonium (MA+), cesium (Cs+), lead (Pb2+), bromide (Br-), and iodide (I-), dramatic compositional changes are observed following storage of the inks in nitrogen in the dark. We show that hydrolysis of DMF in the precursor solution forms dimethylammonium formate, which subsequently incorporates into the MHP film to compromise the ability of Cs+ and MA+ to stabilize FA+-based MHP. The changes in solution chemistry lead to a modification of the perovskite film stoichiometry, band gap, and structure. The solid precursor salts are stable when ball-milled into a powder, allowing for the storage of large quantities of stoichiometric precursor materials.

  19. Variaciones sobre el concepto de ética

    OpenAIRE

    Pérez Oliva, Elizabeth; Velasco, José Armando

    2007-01-01

    A lo largo de la historia, pensadores han dado ideas y teorías sobre la ética, pero todos concuerdan en que es una arte de la filosofía que trata de los actos morales, normas de conducta sobre el bien y el mal en el ser humano; término desarrollado a través del tiempo.

  20. Precursors to potential severe core damage accidents: 1992, a status report

    International Nuclear Information System (INIS)

    1993-12-01

    This document is part of a report which documents 1992 operational events selected as accident sequence precursors. This report describes the 27 precursors identified from the 1992 licensee event reports. It also describe containment-related events; open-quote interesting close-quote events; potentially significant events that were considered impractical to analyze; copies of the licensee event reports which were cited in the cases above; and comments from the licensee and NRC in response to the preliminary reports

  1. Designing high performance precursors for atomic layer deposition of silicon oxide

    Energy Technology Data Exchange (ETDEWEB)

    Mallikarjunan, Anupama, E-mail: mallika@airproducts.com; Chandra, Haripin; Xiao, Manchao; Lei, Xinjian; Pearlstein, Ronald M.; Bowen, Heather R.; O' Neill, Mark L. [Air Products and Chemicals, Inc., 1969 Palomar Oaks Way, Carlsbad, California 92011 (United States); Derecskei-Kovacs, Agnes [Air Products and Chemicals, Inc., 7201 Hamilton Blvd., Allentown, Pennsylvania 18195 (United States); Han, Bing [Air Products and Chemicals, Inc., 2 Dongsanhuan North Road, Chaoyang District, Beijing 100027 (China)

    2015-01-15

    Conformal and continuous silicon oxide films produced by atomic layer deposition (ALD) are enabling novel processing schemes and integrated device structures. The increasing drive toward lower temperature processing requires new precursors with even higher reactivity. The aminosilane family of precursors has advantages due to their reactive nature and relative ease of use. In this paper, the authors present the experimental results that reveal the uniqueness of the monoaminosilane structure [(R{sub 2}N)SiH{sub 3}] in providing ultralow temperature silicon oxide depositions. Disubstituted aminosilanes with primary amines such as in bis(t-butylamino)silane and with secondary amines such as in bis(diethylamino)silane were compared with a representative monoaminosilane: di-sec-butylaminosilane (DSBAS). DSBAS showed the highest growth per cycle in both thermal and plasma enhanced ALD. These findings show the importance of the arrangement of the precursor's organic groups in an ALD silicon oxide process.

  2. Development of techniques for tagging precursor and essential chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Swansiger, W.A.; Shepodd, T.J. [Sandia National Labs., Livermore, CA (United States); Phillips, M.L.F. [Sandia National Labs., Albuquerque, NM (United States)

    1994-01-01

    The ability to identify the manufacturers and distributors of chemicals seized in raids of illicit drug labs would be of great value in controlling the diversion of these chemicals. We developed a tagging scheme based on the addition of sub-ppM concentrations of various combinations of rare-earth elements to the target chemicals and evaluated a number of techniques for detecting the tags. We developed soluble tags for tagging liquids and selected Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) as the preferred detection technique. We developed insoluble tags for tagging solids and developed methods to analyze them and mix them into solid precursors. We have successfully demonstrated the tagging of several solvents and two of the precursor chemicals used in one of the most popular clandestine methamphetamine syntheses (ephedrine reacting with hydriodic acid/red phosphorus). The tagging scheme is capable of yielding tens of thousands of signatures (using holmium as an internal standard and up to 9 rare-earths at up to 3 concentrations yields 3{sup 9} {minus} 1 = 19,682 signatures) and is applicable to most of the chemicals on the precursor and essential chemicals list. In the concentrations employed, the tags are safe enough to be added to pharmaceuticals and cheap enough to tag tanker loads of chemicals.

  3. Earthquake prediction the ory and its relation to precursors

    International Nuclear Information System (INIS)

    Negarestani, A.; Setayeshi, S.; Ghannadi-Maragheh, M.; Akasheh, B.

    2001-01-01

    Since we don't have enough knowledge about the Physics of earthquakes. therefore. the study of seismic precursors plays an important role in earthquake prediction. Earthquake prediction is a science which discusses about precursory phenomena during seismogenic process, and then investigates the correlation and association among them and the intrinsic relation between precursors and the seismogenic process. ar the end judges comprehensively the seismic status and finally makes earthquake prediction. There are two ways for predicting earthquake prediction. The first is to study the physics of seismogenic process and to determine the parameters in the process based on the source theories and the second way is to use seismic precursors. In this paper the theory of earthquake is reviewed. We also study theory of earthquake using models of earthquake origin, the relation between seismogenic process and various accompanying precursory phenomena. The earthquake prediction is divided into three categories: long-term, medium-term and short-term. We study seismic anomalous behavior. electric field, crustal deformation, gravity. magnetism of earth. change of groundwater variation. groundwater geochemistry and change of Radon gas emission. Finally, it is concluded the there is a correlation between Radon gas emission and earthquake phenomena. Meanwhile, there are some samples from actual processing in this area

  4. Synthesis and characterization of organosilicon compounds as novel precursors for CVD processes

    Energy Technology Data Exchange (ETDEWEB)

    Ermakova, E.N.; Sysoev, S.V.; Nikulina, L.D. [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Acad. Lavrentiev Ave. 3, Novosibirsk 630090 (Russian Federation); Tsyrendorzhieva, I.P.; Rakhlin, V.I. [Favorskii Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorskii Str. 1, Irkutsk 664033 (Russian Federation); Kosinova, M.L., E-mail: marina@niic.nsc.ru [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Acad. Lavrentiev Ave. 3, Novosibirsk 630090 (Russian Federation)

    2015-12-20

    Highlights: • The temperature dependences of vapor pressure of four precursors have been measured. • The experimental data were used to calculate standard thermodynamic functions. • The thermodynamic modelling of SiC{sub x}N{sub y} films formation has been performed. - Abstract: Chemical vapor deposition using single-source organosilicon precursors is one of the most effective ways to produce multifunctional SiC{sub x}N{sub y} films. It is worth mentioning that the precursor molecule design affects both the composition and properties of films. Four organosilicon compounds containing a phenyl substituent (namely, trimethylphenylsilane, trimethyl(phenylamino) silane, trimethyl(benzylamino)silane and bis(trimethylsilyl)phenylamine) have been synthesized and characterized as potential CVD precursors for SiC{sub x}N{sub y} films synthesis. The compounds have been shown to be volatile and stable enough to be used in chemical vapor deposition of SiC{sub x}N{sub y} films. Thermodynamic modeling of the film deposition from the gaseous mixture of trimethylphenylsilane and ammonia in Si–C–N–H system has demonstrated that SiC{sub x}N{sub y} films can be deposited, and there is an opportunity to determine the area of appropriate deposition conditions.

  5. Sonochemically synthesized iron-doped zinc oxide nanoparticles: Influence of precursor composition on characteristics

    International Nuclear Information System (INIS)

    Roy, Anirban; Maitra, Saikat; Ghosh, Sobhan; Chakrabarti, Sampa

    2016-01-01

    Highlights: • Sonochemical synthesis of iron-doped zinc oxide nanoparticles. • Green synthesis without alkali at room temperature. • Characterization by UV–vis spectroscopy, FESEM, XRD and EDX. • Influence of precursor composition on characteristics. • Composition and characteristics are correlated. - Abstract: Iron-doped zinc oxide nanoparticles have been synthesized sonochemically from aqueous acetyl acetonate precursors of different proportions. Synthesized nanoparticles were characterized with UV–vis spectroscopy, X-ray diffraction and microscopy. Influences of precursor mixture on the characteristics have been examined and modeled. Linear correlations have been proposed between dopant dosing, extent of doping and band gap energy. Experimental data corroborated with the proposed models.

  6. Fluorescing macerals from wood precursors

    Energy Technology Data Exchange (ETDEWEB)

    Stout, S A; Bensley, D F

    1987-01-01

    A preliminary investigation into the origin of wood-derived macerals has established the existence of autofluorescent maceral precursors in the secondary xylem of swamp-inhabiting plant species. The optical character and fluorescent properties of microtomed thin-sections of modern woods from the Florida Everglades and Okefenokee Swamp, Georgia are compared to the character and properties of their peatified equivalents from various Everglades and Okefenokee peat horizons and their lignitic equivalents from the Brandon lignite of Vermont and the Trail Ridge lignitic peat from northern Florida. The inherent fluorescence of woody cell walls is believed to be caused by lignin though other cell wall components may contribute. The fluorescence spectra for several wood and cell types had a ..gamma../sub m//sub a//sub x/ of 452 nm and Q value of 0.00. The color as observed in blue light and the spectral geometry as measured in UV light of peatified and lignitic woody cell walls (potential textinites) may change progressively during early coalification. Cell wall-derived maceral material is shown to maintain its fluorescing properties after being converted to a structureless material, perhaps a corpohuminite or humodetrinite precursor. Fluorescing xylem cell contents, such as condensed tannins or essential oils, can maintain the fluorescent character through early coalification. Xylem cell walls and xylem cell contents are shown to provide fluorescing progenitor materials which would not require subsequent infusion with 'lipid' materials to account for their fluorescence as phytoclast material or as macerals in coal. 35 references.

  7. Different radiosensitivities of mast-cell precursors in the bone marrow and skin of mice

    International Nuclear Information System (INIS)

    Kitamura, Y.; Yokoyama, M.; Sonoda, T.; Mori, K.J.

    1983-01-01

    Although tissue mast cells are derived from the bone marrow, some descendants of bone marrow-derived precursors retain the ability to proliferate and differentiate into mast cells even after localization in the skin. The purpose of the present study was to determine the D 0 values for mast-cell precursors in the bone marrow and those localized in the skin. Bone marrow cells were removed from (WB X C57BL/6)F 1 +/+ mice after various doses of irradiation and injected into the skin of the congenic W/W/sup v/ mice which were genetically without mast cells. Radiosensitivity of mast-cell precursors in the bone marrow was evaluated by determining the proportion of the injection sites at which mast cells did not appear. For the assay of the radiosensitivity of mast-cell precursors localized in the skin, pieces of skin were removed from beige C57BL/6 (bg/sup J//bg/sup J/, Chediak-Higashi syndrome) mice after various doses of irradiation and grafted onto the backs of the normal C57BL/6 mice. Radiosensitivity of mast-cell precursors in the skin was evaluated by determining the decrease of beige-type mast cells which possessed giant granules. Mast-cell precursors in the bone marrow were much more radiosenitive than those localized in the skin. D 0 value was about 100 rad for the former and about 800 rad for the latter

  8. Hemopoietic precursor cell regeneration following irradiation and syngeneic marrow transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Melchner, H. von

    1983-01-01

    The transplantation of hemopoietic cells into adequately pretreated recipients represents one of the most promising approaches in the treatment of immunohematological disorders such as aplastic anemia, immunodeficiency diseases, leukemias and malignant lymphomas. The basic property of the hemopoietic cells permitting such therapeutic procedure, namely, the capacity of hemopoietic precursors to actively proliferate and differentiate in recipients suffering the consequences of various kinds of hemopoietic failure, represents the subject of the present review. The main cell populations addressed in the subsequent sections are the hemopoietic precursor cells. Mature end cells and in particular lymphocytes did not receive as much attention.

  9. Polymethacrylic acid as a new precursor of CuO nanoparticles

    Science.gov (United States)

    Hosny, Nasser Mohammed; Zoromba, Mohamed Shafick

    2012-11-01

    Polymethacrylic acid and its copper complexes have been synthesized and characterized. These complexes have been used as precursors to produce CuO nanoparticles by thermal decomposition in air. The stages of decompositions and the calcination temperature of the precursors have been determined from thermal analyses (TGA). The obtained CuO nanoparticles have been characterized by X-ray diffraction (XRD), scanning tunneling microscopy (STM) and transmission electron microscopy (TEM). XRD showed a monoclinic structure with particle size 8-20 nm for the synthesized copper oxide nanoparticles. These nanoparticles are catalytically active in decomposing hydrogen peroxide and a mechanism of decomposition has been suggested.

  10. Essential elucidation for preparation of supported nickel phosphide upon nickel phosphate precursor

    International Nuclear Information System (INIS)

    Liu, Xuguang; Xu, Lei; Zhang, Baoquan

    2014-01-01

    Preparation of supported nickel phosphide (Ni 2 P) depends on nickel phosphate precursor, generally related to its chemical composition and supports. Study of this dependence is essential and meaningful for the preparation of supported Ni 2 P with excellent catalytic activity. The chemical nature of nickel phosphate precursor is revealed by Raman and UV–vis spectra. It is found that initial P/Ni mole ratio ≥0.8 prohibits the Ni-O-Ni bridge bonding (i.e., nickel oxide). This chemical bonding will not result in Ni 2 P structure, verified by XRD characterization results. The alumina (namely, γ-Al 2 O 3 , θ-Al 2 O 3 , or α-Al 2 O 3 ) with distinct physiochemical properties also results in diverse chemical nature of nickel phosphate, and then different nickel phosphides. The influence of alumina support on producing Ni 2 P was explained by the theory of surface energy heterogeneity, calculated by the NLDFT method based on N 2 -sorption isotherm. The uniform surface energy of α-Al 2 O 3 results only in the nickel phosphosate precursor and thus the Ni 2 P phase. - Graphical abstract: Surface energy heterogeneity in alumina (namely α-Al 2 O 3 , θ-Al 2 O 3 , and γ-Al 2 O 3 ) supported multi-oxidic precursors with different reducibilities and thus diverse nickel phosphides (i.e., Ni 3 P, Ni 12 P 5 , Ni 2 P). - Highlights: • Preparing pure Ni 2 P. • Elucidating nickel phosphate precursor. • Associating with surface energy

  11. Use of social adaptability index to explain self-care and diabetes outcomes.

    Science.gov (United States)

    Campbell, Jennifer A; Walker, Rebekah J; Smalls, Brittany L; Egede, Leonard E

    2017-06-20

    To examine whether the social adaptability index (SAI) alone or components of the index provide a better explanatory model for self-care and diabetes outcomes. Six hundred fifteen patients were recruited from two primary care settings. A series of multiple linear regression models were run to assess (1) associations between the SAI and diabetes self-care/outcomes, and (2) associations between individual SAI indicator variables and diabetes self-care/outcomes. Separate models were run for each self-care behavior and outcome. Two models were run for each dependent variable to compare associations with the SAI and components of the index. The SAI has a significant association with the mental component of quality of life (0.23, p < 0.01). In adjusted analyses, the SAI score did not have a significant association with any of the self-care behaviors. Individual components from the index had significant associations between self-care and multiple SAI indicator variables. Significant associations also exist between outcomes and the individual SAI indicators for education and employment. In this population, the SAI has low explanatory power and few significant associations with diabetes self-care/outcomes. While the use of a composite index to predict outcomes within a diabetes population would have high utility, particularly for clinical settings, this SAI lacks statistical and clinical significance in a representative diabetes population. Based on these results, the index does not provide a good model fit and masks the relationship of individual components to diabetes self-care and outcomes. These findings suggest that five items alone are not adequate to explain or predict outcomes for patients with type 2 diabetes.

  12. Variability in effective radiating area and output power of new ultrasound transducers at 3 MHz.

    Science.gov (United States)

    Johns, Lennart D; Straub, Stephen J; Howard, Samuel M

    2007-01-01

    Spatial average intensity (SAI) is often used by clinicians to gauge therapeutic ultrasound dosage, yet SAI measures are not directly regulated by US Food and Drug Administration (FDA) standards. Current FDA guidelines permit a possible 50% to 150% minimum to maximum range of SAI values, potentially contributing to variability in clinical outcomes. To measure clinical values that describe ultrasound transducers and to determine the degree of intramanufacturer and intermanufacturer variability in effective radiating area, power, and SAI when the transducer is functioning at 3 MHz. A descriptive and interferential approach was taken to this quasi-experimental design. Measurement laboratory. Sixty-six 5-cm(2) ultrasound transducers were purchased from 6 different manufacturers. All transducers were calibrated and then assessed using standardized measurement techniques; SAI was normalized to account for variability in effective radiating area, resulting in an nSAI. Effective radiating area, power, and nSAI. All manufacturers with the exception of Omnisound (P = .534) showed a difference between the reported and measured effective radiating area values (P nSAI (P < .05) than all other manufacturers functioning at 3 MHz. Intramanufacturer variability in SAI ranged from 16% to 35%, and intermanufacturer variability ranged from 22% to 61%. Clinicians should consider treatment values of each individual transducer, regardless of the manufacturer. In addition, clinicians should scrutinize the power calibration and recalibration record of the transducer and adjust clinical settings as needed for the desired level of heating. Our data may aid in explaining the reported heating differences among transducers from different manufacturers. Stricter FDA standards regarding effective radiating area and total power are needed, and standards regulating SAI should be established.

  13. Comunidad Andina y negocios internacionales: una visión desde su institucionalidad y supranacionalidad

    Directory of Open Access Journals (Sweden)

    Luis Nelson Beltrán Mora

    2013-03-01

    Full Text Available Rev.esc.adm.neg Este trabajo, presenta la evolución de la integración de la Comunidad Andina (CAN desde la perspectiva del derecho internacional; se deduce que el Sistema de Integración Andino (SAI, no sólo ha permitido la promoción de los negocios sino que el Derecho Comunitario (DC desarrollado en el grupo, blinda los tratados comerciales dando institucionalidad y supranacionalidad a la CAN, al punto de convertirse en referencia para imitarlo en la reciente creada Unión de Naciones del Sur (UNASUR. En la CAN, el nuevo regionalismo abierto genera incertidumbre sobre el futuro de dicho bloque.

  14. Using ADOPT Algorithm and Operational Data to Discover Precursors to Aviation Adverse Events

    Science.gov (United States)

    Janakiraman, Vijay; Matthews, Bryan; Oza, Nikunj

    2018-01-01

    The US National Airspace System (NAS) is making its transition to the NextGen system and assuring safety is one of the top priorities in NextGen. At present, safety is managed reactively (correct after occurrence of an unsafe event). While this strategy works for current operations, it may soon become ineffective for future airspace designs and high density operations. There is a need for proactive management of safety risks by identifying hidden and "unknown" risks and evaluating the impacts on future operations. To this end, NASA Ames has developed data mining algorithms that finds anomalies and precursors (high-risk states) to safety issues in the NAS. In this paper, we describe a recently developed algorithm called ADOPT that analyzes large volumes of data and automatically identifies precursors from real world data. Precursors help in detecting safety risks early so that the operator can mitigate the risk in time. In addition, precursors also help identify causal factors and help predict the safety incident. The ADOPT algorithm scales well to large data sets and to multidimensional time series, reduce analyst time significantly, quantify multiple safety risks giving a holistic view of safety among other benefits. This paper details the algorithm and includes several case studies to demonstrate its application to discover the "known" and "unknown" safety precursors in aviation operation.

  15. P120-Catenin Regulates Early Trafficking Stages of the N-Cadherin Precursor Complex.

    Directory of Open Access Journals (Sweden)

    Diana P Wehrendt

    Full Text Available It is well established that binding of p120 catenin to the cytoplasmic domain of surface cadherin prevents cadherin endocytosis and degradation, contributing to cell-cell adhesion. In the present work we show that p120 catenin bound to the N-cadherin precursor, contributes to its anterograde movement from the endoplasmic reticulum (ER to the Golgi complex. In HeLa cells, depletion of p120 expression, or blocking its binding to N-cadherin, increased the accumulation of the precursor in the ER, while it decreased the localization of mature N-cadherin at intercellular junctions. Reconstitution experiments in p120-deficient SW48 cells with all three major isoforms of p120 (1, 3 and 4 had similar capacity to promote the processing of the N-cadherin precursor to the mature form, and its localization at cell-cell junctions. P120 catenin and protein tyrosine phosphatase PTP1B facilitated the recruitment of the N-ethylmaleimide sensitive factor (NSF, an ATPase involved in vesicular trafficking, to the N-cadherin precursor complex. Dominant negative NSF E329Q impaired N-cadherin trafficking, maturation and localization at cell-cell junctions. Our results uncover a new role for p120 catenin bound to the N-cadherin precursor ensuring its trafficking through the biosynthetic pathway towards the cell surface.

  16. Perfluoroalkyl acids and their precursors in Swedish food: The relative importance of direct and indirect dietary exposure

    International Nuclear Information System (INIS)

    Gebbink, Wouter A.; Glynn, Anders; Darnerud, Per Ola; Berger, Urs

    2015-01-01

    We analyzed food market basket samples obtained in Sweden from 1999, 2005, and 2010 for perfluoroalkyl acids (PFAAs) and a range of precursor compounds. Perfluorooctane sulfonic acid (PFOS) precursors were detected in all food year pools with the highest concentrations in 1999. Six polyfluoroalkyl phosphate diesters (diPAPs, 4:2/6:2, 6:2/6:2, 6:2/8:2, 8:2/8:2, 6:2/10:2, and 10:2/10:2) were detected in the year pools with the highest ∑diPAP concentrations in 1999 and 2005. All precursors were predominantly found in meat, fish, and/or eggs based on analysis of individual food groups from 1999. Based on year pools, PFOS precursors contributed between 4 and 1% as an indirect source to total dietary PFOS intakes between 1999 and 2010. Perfluorohexanoic acid (PFHxA) exposure originated entirely from diPAPs, whereas for perfluorooctanoic acid (PFOA) and perfluorodecanoic acid (PFDA), diPAPs contributed between 1 and 19% to total exposure. The lowest precursor contributions were generally seen in food samples from 2010. - Highlights: • Three PFOS precursors and six diPAPs were detected in food pools. • Precursor concentrations were highest in 1999 and 2005 food pools, and lowest in 2010. • The relative importance of precursors to total PFOS dietary intake was <4%. • The relative importance of diPAPs as an indirect dietary source of PFCAs was chain length dependent. - The relative contribution of precursors to PFOS dietary intakes is small, whereas the contribution of diPAPs to PFCA dietary intakes varies with the PFCA chain length

  17. Childhood Precursors of Adult Borderline Personality Disorder Features: A Longitudinal Study.

    Science.gov (United States)

    Cramer, Phebe

    2016-07-01

    This study identifies childhood personality traits that are precursors of adult Borderline Personality Disorder (BPD) features. In a longitudinal study, childhood personality traits were assessed at age 11 (N = 100) using the California Child Q-set (CCQ: Block and Block, 1980). A number of these Q-items were found to be significantly correlated (p personality dimensions: Impulsivity and Nonconformity/Aggression. The findings thus provide evidence that childhood personality traits predict adult BPD features. Identifying such childhood precursors provides an opportunity for early intervention.

  18. Radon as an earthquake precursor

    International Nuclear Information System (INIS)

    Planinic, J.; Radolic, V.; Vukovic, B.

    2004-01-01

    Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors during a four-year period. Seismic activities, as well as barometric pressure, rainfall and air temperature were also observed. The influence of meteorological parameters on temporal radon variations was investigated, and a respective equation of the multiple regression was derived. The earthquakes with magnitude ≥3 at epicentral distances ≤200 km were recognized by means of radon anomaly. Empirical equations between earthquake magnitude, epicentral distance and precursor time were examined, and respective constants were determined

  19. Radon as an earthquake precursor

    Energy Technology Data Exchange (ETDEWEB)

    Planinic, J. E-mail: planinic@pedos.hr; Radolic, V.; Vukovic, B

    2004-09-11

    Radon concentrations in soil gas were continuously measured by the LR-115 nuclear track detectors during a four-year period. Seismic activities, as well as barometric pressure, rainfall and air temperature were also observed. The influence of meteorological parameters on temporal radon variations was investigated, and a respective equation of the multiple regression was derived. The earthquakes with magnitude {>=}3 at epicentral distances {<=}200 km were recognized by means of radon anomaly. Empirical equations between earthquake magnitude, epicentral distance and precursor time were examined, and respective constants were determined.

  20. Understanding the Thermal Properties of Precursor-Ionomers to Optimize Fabrication Processes for Ionic Polymer-Metal Composites (IPMCs

    Directory of Open Access Journals (Sweden)

    Sarah Trabia

    2018-04-01

    Full Text Available Ionic polymer-metal composites (IPMCs are one of many smart materials and have ionomer bases with a noble metal plated on the surface. The ionomer is usually Nafion, but recently Aquivion has been shown to be a promising alternative. Ionomers are available in the form of precursor pellets. This is an un-activated form that is able to melt, unlike the activated form. However, there is little study on the thermal characteristics of these precursor ionomers. This lack of knowledge causes issues when trying to fabricate ionomer shapes using methods such as extrusion, hot-pressing, and more recently, injection molding and 3D printing. To understand the two precursor-ionomers, a set of tests were conducted to measure the thermal degradation temperature, viscosity, melting temperature, and glass transition. The results have shown that the precursor Aquivion has a higher melting temperature (240 °C than precursor Nafion (200 °C and a larger glass transition range (32–65°C compared with 21–45 °C. The two have the same thermal degradation temperature (~400 °C. Precursor Aquivion is more viscous than precursor Nafion as temperature increases. Based on the results gathered, it seems that the precursor Aquivion is more stable as temperature increases, facilitating the manufacturing processes. This paper presents the data collected to assist researchers in thermal-based fabrication processes.

  1. NOx emissions trading: Precursor to future growth

    International Nuclear Information System (INIS)

    Colella, A.

    1993-01-01

    Title I of the Clean Air Act Amendments (CAAA) of 1990 specified the framework for enhanced regulation in ozone non-attainment areas with increasingly stringent requirements dependent on the area classification - marginal, moderate, serious, severe or extreme. Before the CAAA were passed, only volatile organic compounds (VOCs) were regulated as precursors to ozone formation, Now, by statute, emissions of nitrogen oxides (NO x ) are also regulated as ozone precursor. Under the CAAA, new sources and modifications of existing sources are subject to Title I permitting requirements in ozone non-attainment areas if emissions of NO x and/or VOCs exceed certain triggering levels. For many new or facility expansion projects, especially power generation, the NO x thresholds are easily exceeded thus triggering Title I non-attainment new source review which requires application of control technology to new equipment which results in the Lowest Achievable Emission Rate (LAER), and securing emission reductions either internally or from other major sources to offset the increased emission from the new or modified source. The selection of a LAER technology is generally within an applicant's control. An applicant can determine up-front the engineering and cost considerations associated with LAER technology is assessing a project's viability. However, without a clear source of emission offsets of a means to secure them, assessing project viability could be difficult if not impossible. No available emission offsets means no industrial growth. For sources of NO x undergoing Title I new source review, a regional or state banking system that facilitates NO x emissions trading is needed as a precursor to future growth. This paper presents an overview of EPA's Emissions Trading Policy and Title I new source review offset provisions. Industry's concerns about emissions trading and recommendations for future trading programs are presented

  2. Precursor Dependent Structural Properties and Antibacterial Activity ...

    Indian Academy of Sciences (India)

    71

    10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30 ... absorption spectroscopy, Scanning electron microscopy (SEM) and Zeta ... The antibacterial activity of the synthesized CuO were studied against human .... Sample d : Copper oxide synthesized with cupric sulphate as precursor ...... Chem.4 86.

  3. Escrito sobre el cuerpo

    Directory of Open Access Journals (Sweden)

    Antonio Malalana Ureña

    2013-09-01

    Full Text Available El catálogo, en una edición bilingüe español-inglés, es una pequeña guía de la exposición Shirin Neshat. Escrito sobre el cuerpo, muestra que se integra dentro de los actos de PHOTOESPAÑA13, el festival internacional de fotografía y artes visuales. El esquema del libro es sencillo y los textos son extremadamente divulgativos. El primero de ellos, Escrito sobre el cuerpo (pp. 10-15, cuyo autor es Octavio Zaya, comisario de la exposición, resume la trayectoria de esta intelectual, que "interactúa" con la fotografía y los formatos audiovisuales, y nos presenta la argumentación narrativa de los documentos expuestos, contextualizando la obra recopilada.

  4. Layered niobate KNb3O8 synthesized by the polymeric precursor method

    International Nuclear Information System (INIS)

    Souza, J.K.D. de; Honório, L.M.C.; Torres, S.M.; Santos, I.M.G.; Maia, A.S.; Ferreira, J.M.

    2018-01-01

    The polymeric precursor method was used for the synthesis of KNb 3 O 8 and compared to the solid-state method. The materials were characterized by X-ray diffraction (XRD), infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and determination of surface area and total pore volume by nitrogen isotherms at 77 K. The material prepared by the polymeric precursor method was single-phase while K 2 Nb 4 O 11 was obtained as secondary phase when the solid state method was used, as evidenced by the XRD patterns and the Raman spectra. The morphology of the materials was significantly altered by the synthesis method, as the KNb 3 O 8 prepared by the polymeric precursor method presented a more porous morphology leading to a higher surface area and pore volume. (author)

  5. Precursors of vertebrate peptide antibiotics dermaseptin b and adenoregulin have extensive sequence identities with precursors of opioid peptides dermorphin, dermenkephalin, and deltorphins.

    Science.gov (United States)

    Amiche, M; Ducancel, F; Mor, A; Boulain, J C; Menez, A; Nicolas, P

    1994-07-08

    The dermaseptins are a family of broad spectrum antimicrobial peptides, 27-34 amino acids long, involved in the defense of the naked skin of frogs against microbial invasion. They are the first vertebrate peptides to show lethal effects against the filamentous fungi responsible for severe opportunistic infections accompanying immunodeficiency syndrome and the use of immunosuppressive agents. A cDNA library was constructed from skin poly(A+) RNA of the arboreal frog Phyllomedusa bicolor and screened with an oligonucleotide probe complementary to the COOH terminus of dermaseptin b. Several clones contained a full-length DNA copy of a 443-nucleotide mRNA that encoded a 78-residue dermaseptin b precursor protein. The deduced precursor contained a putative signal sequence at the NH2 terminus, a 20-residue spacer sequence extremely rich (60%) in glutamic and aspartic acids, and a single copy of a dermaseptin b progenitor sequence at the COOH terminus. One clone contained a complete copy of adenoregulin, a 33-residue peptide reported to enhance the binding of agonists to the A1 adenosine receptor. The mRNAs encoding adenoregulin and dermaseptin b were very similar: 70 and 75% nucleotide identities between the 5'- and 3'-untranslated regions, respectively; 91% amino acid identity between the signal peptides; 82% identity between the acidic spacer sequences; and 38% identity between adenoregulin and dermaseptin b. Because adenoregulin and dermaseptin b have similar precursor designs and antimicrobial spectra, adenoregulin should be considered as a new member of the dermaseptin family and alternatively named dermaseptin b II. Preprodermaseptin b and preproadenoregulin have considerable sequence identities to the precursors encoding the opioid heptapeptides dermorphin, dermenkephalin, and deltorphins. This similarity extended into the 5'-untranslated regions of the mRNAs. These findings suggest that the genes encoding the four preproproteins are all members of the same family

  6. Endogenous peptide profile for elucidating biosynthetic processing of the ghrelin precursor.

    Science.gov (United States)

    Tsuchiya, Takashi; Iwakura, Hiroshi; Minamino, Naoto; Kangawa, Kenji; Sasaki, Kazuki

    2017-09-02

    Ghrelin is an orexigenic peptide primarily produced by gastric endocrine cells. The biosynthetic cleavage site of ghrelin has been well documented, but how its downstream region undergoes proteolytic processing remains poorly explored. Here, we provide the first snapshot of endogenous peptides from the ghrelin precursor by profiling the secretopeptidome of cultured mouse ghrelin-producing cells during exocytosis. Mapping of MS/MS sequenced peptides to the precursor highlighted three atypical monobasic processing sites, including the established C-terminus of ghrelin and the N-terminal cleavage site for obestatin, a putative 23-amino-acid C-terminally amidated peptide. However, we found that mouse obestatin does not occur in the form originally reported, but that a different amidation site is used to generate a shorter peptide. These data can be extended to study and characterize the precursor-derived peptides located downstream of ghrelin in different biological contexts. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Deformaciones faciales y sus influencias sobre el psiquismo

    Directory of Open Access Journals (Sweden)

    Guillermo Nieto Cano

    1957-04-01

    Full Text Available Creemos haber dejado establecido, en síntesis, que todas las minusvalías físicas repercuten sobre el psiquismo, y que entre éstas las deformaciones faciales, por su ostentosa evidencia, son las que afectan más seriamente al individuo y modifican por eso más radicalmente su conducta, incidiendo así, en forma trascendental, sobre la colectividad. Tales defectos constituyen, por consiguiente, un serio problema humano, cuyo estudio y remedio incumbe no solamente al esteta cirujano, sino que interesa a todos aquellos que puedan influir sobre la estabilidad armónica y la buena marcha de la sociedad en que viven.

  8. Onset of Spinal Cord Astrocyte Precursor Emigration from the Ventricular Zone Involves the Zeb1 Transcription Factor

    Directory of Open Access Journals (Sweden)

    David Ohayon

    2016-11-01

    Full Text Available During spinal cord development, astrocyte precursors arise from neuroepithelial progenitors, delaminate from the ventricular zone, and migrate toward their final locations where they differentiate. Although the mechanisms underlying their early specification and late differentiation are being deciphered, less is known about the temporal control of their migration. Here, we show that the epithelial-mesenchymal transition regulator Zeb1 is expressed in glial precursors and report that loss of Zeb1 function specifically delays the onset of astrocyte precursor delamination from the ventricular zone, correlating with transient deregulation of the adhesion protein Cadherin-1. Consequently, astrocyte precursor invasion into the Zeb1−/− mutant white matter is delayed, and induction of their differentiation is postponed. These findings illustrate how fine regulation of adhesive properties influences the onset of neural precursor migration and further support the notion that duration of exposure of migrating astrocyte precursors to environmental cues and/or their correct positioning influence the timing of their differentiation.

  9. Quantitative analysis of indigo and indigo precursors in leaves of Isatis spp. and Polygonum tinctorium.

    Science.gov (United States)

    Gilbert, Kerry G; Maule, Hamish G; Rudolph, Bernd; Lewis, Mervyn; Vandenburg, Harold; Sales, Ester; Tozzi, Sabrina; Cooke, David T

    2004-01-01

    Analysis of extracts from two woad species (Isatis tinctoria and Isatis indigotica) and Polygonum tinctorium revealed that only one indigo precursor (indican) was present in Polygonum, but two precursors were found in Isatis spp. This was done using high performance liquid chromatography (HPLC), coupled to an evaporative light scattering detector (ELSD). In Isatis spp., the indigo precursors indican and a fraction representing isatan B were identified. The proportion of indican and isatan B was different between the two Isatis spp. tested. For the first time, it was possible to quantify the precursors in woad plant species, and the results were found to be in good agreement with those made from total indigo quantification using two different spectrophotometric methods or a derivatization technique.

  10. Use of organosilicate precursors for transparent coatings on organic substrates by plasma CVD

    International Nuclear Information System (INIS)

    Lasorsa, C; Versaci, R; Perillo, P

    2006-01-01

    This work discusses the production of transparent coatings of SiOxCy on substrates polycarbonated by PECVD at temperatures below 80 o C, with a gaseous mixture using different precursors with which, in similar processes produced the same results with respect to the coating obtained, with the same excellent quality and in accordance with international standards for optic coatings. Chlorinated precursors were excluded because they are highly corrosive as well as those with operating risks (toxic or explosive). The precursors used were tetraethyl orthosilicate (TEOS), tetramethylsilanete (TMS,) tetramethoxy silane (TMOS), hexamethyldisilizane (HMDS), and methyltrimethoxysilane (Z6070), with the contribution of O 2 and methane as reactive gases. Fourier transform infrared spectroscopy (FTIR) was used as well as X-ray generated photoelectron spectroscopy (XPS/ESCA). The functional groups were studied together with the film elements and its mechanical properties, transparency and refraction index. Irregardless of the precursor used, by properly modifying the process variables (pressure of the gaseous mixture, radio frequency power, relationship of processing gases and their flow), similar coatings can be chemically obtained, having the same morphology and, therefore, with identical adherence, structural and optic properties. None of the works consulted refer to the possibility of the indistinct use of different precursors for obtaining the same coating. These results are relevant when considering the difference in costs and their market availability. The influence of the addition of methane was studied in two processing variants, a) with oxygen and methane and b) with oxygen alone. For all the precursors used and with identical processing conditions, the carbon contributed by the addition of methane increased the concentration of carbon compounds, considerably reducing the presence of silanol, which being absorbent produces structural instability and cracking of the

  11. Silicon structuring by etching with liquid chlorine and fluorine precursors using femtosecond laser pulses

    International Nuclear Information System (INIS)

    Radu, C.; Simion, S.; Zamfirescu, M.; Ulmeanu, M.; Enculescu, M.; Radoiu, M.

    2011-01-01

    The aim of this study is to investigate the micrometer and submicrometer scale structuring of silicon by liquid chlorine and fluorine precursors with 200 fs laser pulses working at both fundamental (775 nm) and frequency doubled (387 nm) wavelengths. The silicon surface was irradiated at normal incidence by immersing the Si (111) substrates in a glass container filled with liquid chlorine (CCl 4 ) and fluorine (C 2 Cl 3 F 3 ) precursors. We report that silicon surfaces develop an array of spikes with single step irradiation processes at 775 nm and equally at 387 nm. When irradiating the Si surface with 400 pulses at 330 mJ/cm 2 laser fluence and a 775 nm wavelength, the average height of the formed Si spikes in the case of fluorine precursors is 4.2 μm, with a full width at half maximum of 890 nm. At the same irradiation wavelength chlorine precursors develop Si spikes 4 μm in height and with a full width at half maximum of 2.3 μm with irradiation of 700 pulses at 560 mJ/cm 2 laser fluence. Well ordered areas of submicrometer spikes with an average height of about 500 nm and a width of 300 nm have been created by irradiation at 387 nm by chlorine precursors, whereas the fluorine precursors fabricate spikes with an average height of 700 nm and a width of about 200 nm. Atomic force microscopy and scanning electron microscopy of the surface show that the formation of the micrometer and sub-micrometer spikes involves a combination of capillary waves on the molten silicon surface and laser-induced etching of silicon, at both 775 nm and 387 nm wavelength irradiation. The energy-dispersive x-ray measurements indicate the presence of chlorine and fluorine precursors on the structured surface. The fluorine precursors create a more ordered area of Si spikes at both micrometer and sub-micrometer scales. The potential use of patterned Si substrates with gradient topography as model scaffolds for the systematic exploration of the role of 3D micro/nano morphology on cell

  12. Fission-Based Electric Propulsion for Interstellar Precursor Missions

    International Nuclear Information System (INIS)

    HOUTS, MICHAEL G.; LENARD, ROGER X.; LIPINSKI, RONALD J.; PATTON, BRUCE; POSTON, DAVID; WRIGHT, STEVEN A.

    1999-01-01

    This paper reviews the technology options for a fission-based electric propulsion system for interstellar precursor missions. To achieve a total ΔV of more than 100 km/s in less than a decade of thrusting with an electric propulsion system of 10,000s Isp requires a specific mass for the power system of less than 35 kg/kWe. Three possible configurations are described: (1) a UZrH-fueled,NaK-cooled reactor with a steam Rankine conversion system,(2) a UN-fueled gas-cooled reactor with a recuperated Brayton conversion system, and (3) a UN-fueled heat pipe-cooled reactor with a recuperated Brayton conversion system. All three of these systems have the potential to meet the specific mass requirements for interstellar precursor missions in the near term. Advanced versions of a fission-based electric propulsion system might travel as much as several light years in 200 years

  13. An effective approach to synthesize monolayer tungsten disulphide crystals using tungsten halide precursor

    International Nuclear Information System (INIS)

    Thangaraja, Amutha; Shinde, Sachin M.; Kalita, Golap; Tanemura, Masaki

    2016-01-01

    The synthesis of large-area monolayer tungsten disulphide (WS 2 ) single crystal is critical for realistic application in electronic and optical devices. Here, we demonstrate an effective approach to synthesize monolayer WS 2 crystals using tungsten hexachloride (WCl 6 ) as a solid precursor in atmospheric chemical vapor deposition process. In this technique, 0.05M solution of WCl 6 in ethanol was drop-casted on SiO 2 /Si substrate to create an even distribution of the precursor, which was reduced and sulfurized at 750 °C in Ar atmosphere. We observed growth of triangular, star-shaped, as well as dendritic WS 2 crystals on the substrate. The crystal geometry evolves with the shape and size of the nuclei as observed from the dendritic structures. These results show that controlling the initial nucleation and growth process, large WS 2 single crystalline monolayer can be grown using the WCl 6 precursor. Our finding shows an easier and effective approach to grow WS 2 monolayer using tungsten halide solution-casting, rather than evaporating the precursor for gas phase reaction

  14. N-Nitroso Compound Precursors in some Nigerian Forage Crops ...

    African Journals Online (AJOL)

    N-Nitroso Compound Precursors in some Nigerian Forage Crops. ... were analyzed as their sulphonamides by gas chromatography interfaced with a chemiluminescence detector-Thermal Energy Analyzer modified for use in nitrogen mode.

  15. Comentarios sobre la Ley de Ordenamiento Territorial Sostenible

    Directory of Open Access Journals (Sweden)

    Arturo J. Yglesias

    2014-04-01

    Full Text Available La denominada Ley de Ordenamiento Territorial Sostenible, no fue bien recibida en el medio jurídico. Tanto los profesores de las diferentes materias de Derecho de nuestra Facultad como las asociaciones profesionales y otros grupos e juristas de nuestro medio, formularon reservas de diverso calibre sobre el texto de la ley que van desde sus aspectos adjetivos como la terminología y redacción hasta cuestiones sustanciales como lo que ella dice sobre el régimen de la propiedad territorial y otras cuestiones vinculadas.Desde el discurso político vimos lanzar opiniones iracundas y alarmistas sobre las modificaciones que la ley estaría haciendo al régimen de la propiedad privada, sobre su supuesta inconstitucionalidad.Nosotros nos vamos a referir a la ley a sus antecedentes y de las críticas que se le hacían, en la parte que toca a nuestra materia, esto es en lo relativo al régimen de la propiedad y debemos decir, a vía de adelanto, que no vemos en ella nada que afecte el derecho de propiedad consagrado por la Constitución de la República, ni los principios generales que regulan la propiedad territorial conforme al Código Civil, conforme a la vieja ley de Centros Poblados, sus modificativas ni demás normas sobre la materia.

  16. Effects of precursors on the crystal structure and photoluminescence of CdS nanocrystalline

    International Nuclear Information System (INIS)

    Fu Zuoling; Zhou Shihong; Shi Jinsheng; Zhang Siyuan

    2005-01-01

    A series of cadmium sulfide (CdS) nanocrystalline were synthesized by precipitation from a mixture of aqueous solutions of cadmium salts and sulfur salts without adding any surface-termination agent. Their crystal structures and particle sizes were determined by X-ray diffraction (XRD). The CdS nanocrystalline precipitated from different precursors exhibited three cases: cubic phase, hexagonal phase and a hybrid of cubic and hexagonal phases. The photoluminescence (PL) of cadmium salt precursors and CdS nanocrystalline is also analyzed. Similar spectral band structure of cadmium salt precursors and CdS nanocrystalline is found. The PL of 3.4, 2.4 and 2.0 nm sized CdS nanocrystalline with the same crystal structure indicated quantum confinement effect

  17. Pistas para pensar las significaciones imaginarias sobre la invariancia

    OpenAIRE

    Bilyk, Pablo Andrés

    2011-01-01

    Este escrito propone un primer esbozo de nominalizaciones sobre las significaciones imaginarias en torno a la idea de invariancia, con el fin de comenzar a mapear categorías para transitar que nos permitan pensar las construcciones fantasmáticas sobre el no-cambio. En definitiva, se trata de avanzar sobre la problematización de los modos de funcionamiento, constitución y reconfiguraciones de las hegemonías en los entramados sociales contemporáneos. Facultad de Periodismo y Comunicación Soc...

  18. Assigning probability gain for precursors of four large Chinese earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Cao, T.; Aki, K.

    1983-03-10

    We extend the concept of probability gain associated with a precursor (Aki, 1981) to a set of precursors which may be mutually dependent. Making use of a new formula, we derive a criterion for selecting precursors from a given data set in order to calculate the probability gain. The probabilities per unit time immediately before four large Chinese earthquakes are calculated. They are approximately 0.09, 0.09, 0.07 and 0.08 per day for 1975 Haicheng (M = 7.3), 1976 Tangshan (M = 7.8), 1976 Longling (M = 7.6), and Songpan (M = 7.2) earthquakes, respectively. These results are encouraging because they suggest that the investigated precursory phenomena may have included the complete information for earthquake prediction, at least for the above earthquakes. With this method, the step-by-step approach to prediction used in China may be quantified in terms of the probability of earthquake occurrence. The ln P versus t curve (where P is the probability of earthquake occurrence at time t) shows that ln P does not increase with t linearly but more rapidly as the time of earthquake approaches.

  19. Wire-Array Precursor Plasma Interactions With On-Axis Foam Targets

    Science.gov (United States)

    Palmer, J. B. A.; Bland, S. N.

    2005-10-01

    The Dynamic Hohlraum (DH) Z-pinch on Z at Sandia National Laboratory (SNL) has been used to drive Inertial Confinement Fusion (ICF) and High Energy Density Physics (HEDP) relevant experiments. The power pulse from the DH cannot yet be reproduced using codes that can reproduce the performance of a Vacuum Hohlraum (VH) configuration on Z. Unlike the VH the DH has a low-density CH foam cylinder placed on the array axis. Production of precursor plasma, prior to the main implosion, is not included in the codes. This plasma is accelerated towards the array axis by the global J x B force and impacts onto the on-axis target. This bombardment alters the foam in various ways. Experiments have been performed on the 1 MA MAGPIE generator at Imperial College, London, to investigate the effect of this precursor bombardment. Diagnostics used were point-projection radiography with x-pinches, x-ray emission framing cameras, shadowgraphy and photoconduction diodes. Results show ablation of low-density plasma from the foam surface and compression of the foam by precursor pressure. Research sponsored by AWE, SNL, the SSAA program of NNSA under DOE Cooperative Agreement DE-FC03-02NA00057.

  20. Reduction of precursor decay anomaly in single crystal lithium fluoride

    Science.gov (United States)

    Sano, Yukio

    2000-08-01

    The purpose of this study is to reveal that the precursor decay anomaly in single crystal lithium fluoride is reduced by Sano's decay curve [Y. Sano, J. Appl. Phys. 85, 7616 (1999)], which is much smaller in slope than Asay's decay curve [J. R. Asay, G. R. Fowles, G. E. Duvall, M. H. Miles, and R. F. Tinder, J. Appl. Phys. 43, 2132 (1972)]. To this end, strain, particle, velocity, and stress in a precursor and near the leading edge of the follower changing with time along Sano's decay curve are first analyzed quantitatively. The analysis verified the existence of degenerate contraction waves I and II and a subrarefaction wave R', and the decay process [Y. Sano, J. Appl. Phys. 77, 3746 (1995)] caused in sequence by evolving followers C, I, II, R', Rb. Next, inequalities relating decay rates qualitatively to plastic strain rates at the leading edge of the follower, which are derived using the properties of the followers, are incorporated into the analysis. Calculation results showed that the plastic strain rates were reduced by low decay rates. This indicates that the precursor decay anomaly might be greatly reduced by Sano's decay curve.

  1. Microglia modulate hippocampal neural precursor activity in response to exercise and aging.

    Science.gov (United States)

    Vukovic, Jana; Colditz, Michael J; Blackmore, Daniel G; Ruitenberg, Marc J; Bartlett, Perry F

    2012-05-09

    Exercise has been shown to positively augment adult hippocampal neurogenesis; however, the cellular and molecular pathways mediating this effect remain largely unknown. Previous studies have suggested that microglia may have the ability to differentially instruct neurogenesis in the adult brain. Here, we used transgenic Csf1r-GFP mice to investigate whether hippocampal microglia directly influence the activation of neural precursor cells. Our results revealed that an exercise-induced increase in neural precursor cell activity was mediated via endogenous microglia and abolished when these cells were selectively removed from hippocampal cultures. Conversely, microglia from the hippocampi of animals that had exercised were able to activate latent neural precursor cells when added to neurosphere preparations from sedentary mice. We also investigated the role of CX(3)CL1, a chemokine that is known to provide a more neuroprotective microglial phenotype. Intraparenchymal infusion of a blocking antibody against the CX(3)CL1 receptor, CX(3)CR1, but not control IgG, dramatically reduced the neurosphere formation frequency in mice that had exercised. While an increase in soluble CX(3)CL1 was observed following running, reduced levels of this chemokine were found in the aged brain. Lower levels of CX(3)CL1 with advancing age correlated with the natural decline in neural precursor cell activity, a state that could be partially alleviated through removal of microglia. These findings provide the first direct evidence that endogenous microglia can exert a dual and opposing influence on neural precursor cell activity within the hippocampus, and that signaling through the CX(3)CL1-CX(3)CR1 axis critically contributes toward this process.

  2. В Венеций раздали лвов Святого Марка / Борис Тух

    Index Scriptorium Estoniae

    Тух, Борис, 1946-

    2008-01-01

    65. Veneetsia filmifestivali auhinnasaajad. Peauhinna sai Darren Aronofsky "Maadleja" ("The Wrestler"), lavastaja Hõbelõvi sai Aleksei German filmiga "Pabersõdur" ("Bumazhnõi soldat"), meesnäitleja auhinna sai Silvio Orlando itaallase Pupi Avati filmist "Papa di Giovanni, II". Lisatud võitjate nimekiri

  3. Lutshim dizaineram vrutshenõ premii Bruno / Tiina Kolk

    Index Scriptorium Estoniae

    Kolk, Tiina

    2008-01-01

    26. septembril tehti Arhitektuuri- ja disainigaleriis teatavaks Eesti disainiauhinna Bruno võitjad. Parima tootedisaini preemia sai Mare Kelpman, parima disainiprojekti eest sai preemia Tarmo Luisk ja eeskujuliku design management'i eest sai preemia ByRoller. Rahvusvahelisse žürii koosseis. Kommenteerib Ilona Gurjanova

  4. The rational design of a Au(I) precursor for focused electron beam induced deposition

    NARCIS (Netherlands)

    Marashdeh, Ali; Tiesma, Thiadrik; van Velzen, Niels J. C.; Harder, Sjoerd; Havenith, Remco W. A.; De Hosson, Jeff T. M.; van Dorp, Willem F.

    2017-01-01

    Au(I) complexes are studied as precursors for focused electron beam induced processing (FEBIP). FEBIP is an advanced direct-write technique for nanometer-scale chemical synthesis. The stability and volatility of the complexes are characterized to design an improved precursor for pure Au deposition.

  5. Study of the influence of the silica source on the synthesis of the zeolite precursor MCM-22; Estudo da influencia da fonte de siilica na sintese do precursor zeolitico MCM-22

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, A.S.; Santos, E.R.F. dos; Leite, R.C.N.; Rodrigues, M.G.F., E-mail: antoniellybarbosa@yahoo.com.br [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais

    2012-07-01

    Zeolite MCM-22 precursors were synthesized under hydrothermal conditions in systems with hexamethyleneimine HMI as bulking agent (driver). Synthesis parameter, such as sources of silica (aerosil® and quartz) was modified to investigate the effects on the morphology and crystallization in precursor MCM-22 zeolite. The products were characterized by X-Ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDX) and Scanning Electron Microscopy (SEM). According to, the X-ray diffraction showed the same characteristic peaks of zeolite MCM-22. It was found that the parameter in this work of synthesis, silica source, affects the hydrothermal synthesis of zeolite MCM-22 precursor. This can be evidenced by the different morphologies found using the different sources of silica. (author)

  6. Laureatõ premii "Zolotoi Oven"

    Index Scriptorium Estoniae

    2003-01-01

    Parima filmi auhinna "Zolotoi Oven" võitis Andrei Zvjagintsevi "Tagasitulek" ("Vozvrashtshenije"), Vadim Abdrashitovi "Magnettormid" ("Magnitnõje buri") sai parima režissööri ja parima stsenaristi auhinna (Aleksandr Mindadze), Pjotr Buslovi "Bumer" sai vaid muusikaauhinna (Sergei Shnurov). Parim meesnäitleja oli Viktor Suhhorukov ("Vaene, vaene Paul") ja naisnäitleja Maria Zvonarjeva A. Proshkini "Trios". A. Sokurovi "Isa ja poeg" sai vaid kunstnikuauhinna (Natalja Kotshergina). Inna Tshurikova sai kõrvalosa auhinna ("S: Govoruhhini "Blagoslovite zhenshtshinu")

  7. Analytical control of the synthesis of the trithio and its precursors by gas chromatography

    International Nuclear Information System (INIS)

    Gonzalez Moreno, M. P.; Perez Garcia, M. M.; Angoso Marina, M.

    1979-01-01

    The synthesis of pesticide Trithio and its precursors has been controlled by G.L. selecting the best separation conditions and responses. The following columns have been used: 20% FFAP on chromo sorb W (a.w.) D.M.C.S. for organophosphate precursor glass column of 5 % Silicone SE-30 on chromo sorb G (a.w.) D.H.C.S. for S-(p-chlorophenyl-chloro methyl) and 12 % Silicone SE-30 modified with 8 % of Neopentyl-glicolsuccinate for Trithio. The relative retention times, retention indices and relative responses for. Trithio and its precursors have been calculated. (Author) 9 refs

  8. The Accident Sequence Precursor program: Methods improvements and current results

    International Nuclear Information System (INIS)

    Minarick, J.W.; Manning, F.M.; Harris, J.D.

    1987-01-01

    Changes in the US NRC Accident Sequence Precursor program methods since the initial program evaluations of 1969-81 operational events are described, along with insights from the review of 1984-85 events. For 1984-85, the number of significant precursors was consistent with the number observed in 1980-81, dominant sequences associated with significant events were reasonably consistent with PRA estimates for BWRs, but lacked the contribution due to small-break LOCAs previously observed and predicted in PWRs, and the frequency of initiating events and non-recoverable system failures exhibited some reduction compared to 1980-81. Operational events which provide information concerning additional PRA modeling needs are also described

  9. Analysis of dependent failures in the ORNL precursor study

    International Nuclear Information System (INIS)

    Ballard, G.M.

    1985-01-01

    The study of dependent failures (or common cause/mode failures) in the safety assessment of potentially hazardous plant is one of the significant areas of uncertainty in performing probabilistic safety studies. One major reason for this uncertainty is that data on dependent failures is apparently not readily available in sufficient quantity to assist in the development and validation of models. The incident reports that were compiled for the ORNL study on Precursors to Severe Core Damage Accidents (NUREG/CR-2497) provide an opportunity to look at the importance of dependent failures in the most significant incidents of recent reactor operations, to look at the success of probabilistic risk assessment (PRA) methods in accounting for the contribution of dependent failures, and to look at the dependent failure incidents with the aim of identifying the most significant problem areas. In this paper an analysis has been made of the incidents compiled in NUREG/CR-2497 and events involving multiple failures which were not independent have been identified. From this analysis it is clear that dependent failures are a very significant contributor to the precursor incidents. The method of enumeration of accident frequency used in NUREG-2497 can be shown to take account of dependent failures and this may be a significant factor contributing to the apparent difference between the precursor accident frequency and typical PRA frequencies

  10. RNAi Mediated curcin precursor gene silencing in Jatropha (Jatropha curcas L.).

    Science.gov (United States)

    Patade, Vikas Yadav; Khatri, Deepti; Kumar, Kamal; Grover, Atul; Kumari, Maya; Gupta, Sanjay Mohan; Kumar, Devender; Nasim, Mohammed

    2014-07-01

    Curcin, a type I ribosomal inhibiting protein-RIP, encoded by curcin precursor gene, is a phytotoxin present in Jatropha (Jatropha curcas L.). Here, we report designing of RNAi construct for the curcin precursor gene and further its genetic transformation of Jatropha to reduce its transcript expression. Curcin precursor gene was first cloned from Jatropha strain DARL-2 and part of the gene sequence was cloned in sense and antisense orientation separated by an intron sequence in plant expression binary vector pRI101 AN. The construction of the RNAi vector was confirmed by double digestion and nucleotide sequencing. The vector was then mobilized into Agrobacterium tumefaciens strain GV 3101 and used for tissue culture independent in planta transformation protocol optimized for Jatropha. Germinating seeds were injured with a needle before infection with Agrobacterium and then transferred to sterilized sand medium. The seedlings were grown for 90 days and genomic DNA was isolated from leaves for transgenic confirmation based on real time PCR with NPT II specific dual labeled probe. Result of the transgenic confirmation analysis revealed presence of the gene silencing construct in ten out of 30 tested seedlings. Further, quantitative transcript expression analysis of the curcin precursor gene revealed reduction in the transcript abundance by more than 98% to undetectable level. The transgenic plants are being grown in containment for further studies on reduction in curcin protein content in Jatropha seeds.

  11. Product Distribution from Precursor Bite Angle Variation in Multitopic Alkyne Metathesis: Evidence for a Putative Kinetic Bottleneck.

    Science.gov (United States)

    Moneypenny, Timothy P; Yang, Anna; Walter, Nathan P; Woods, Toby J; Gray, Danielle L; Zhang, Yang; Moore, Jeffrey S

    2018-05-02

    In the dynamic synthesis of covalent organic frameworks and molecular cages, the typical synthetic approach involves heuristic methods of discovery. While this approach has yielded many remarkable products, the ability to predict the structural outcome of subjecting a multitopic precursor to dynamic covalent chemistry (DCC) remains a challenge in the field. The synthesis of covalent organic cages is a prime example of this phenomenon, where precursors designed with the intention of affording a specific product may deviate dramatically when the DCC synthesis is attempted. As such, rational design principles are needed to accelerate discovery in cage synthesis using DCC. Herein, we test the hypothesis that precursor bite angle contributes significantly to the energy landscape and product distribution in multitopic alkyne metathesis (AM). By subjecting a series of precursors with varying bite angles to AM, we experimentally demonstrate that the product distribution, and convergence toward product formation, is strongly dependent on this geometric attribute. Surprisingly, we discovered that precursors with the ideal bite angle (60°) do not afford the most efficient pathway to the product. The systematic study reported here illustrates how seemingly minor adjustments in precursor geometry greatly affect the outcome of DCC systems. This research illustrates the importance of fine-tuning precursor geometric parameters in order to successfully realize desirable targets.

  12. Associations between musical abilities and precursors of reading in preschool aged children

    OpenAIRE

    Degé, Franziska; Kubicek, Claudia; Schwarzer, Gudrun

    2015-01-01

    The association between music and language, in particular, the overlap in their processing results in the possibility to use one domain for the enhancement of the other. Especially in the preschool years music may be a valuable tool to train language abilities (e.g., precursors of reading). Therefore, detailed knowledge about associations between musical abilities and precursors of reading can be of great use for designing future music intervention studies that target language-related abiliti...

  13. Observation of precursor magnetic oscillations to the H-mode transition of ASDEX

    International Nuclear Information System (INIS)

    Toi, K.; Gernhardt, J.; Klueber, O.; Kornherr, M.

    1988-05-01

    Precursor oscillations to the H-mode transition are identified in magnetic fluctuations of the ASDEX H-mode discharges initiated without a sawtooth. This precursor is m=4/n=1 mode, rotating with f ≅ 10 kHz in the opposite direction to co-injected neutral beams. Time behaviour of the amplitude suggests that the H-mode transition is caused, not by the edge electron temperature, but by the edge current density. (orig.)

  14. Stable amorphous georgeite as a precursor to a high-activity catalyst

    DEFF Research Database (Denmark)

    Kondrat, Simon A.; Smith, Paul J.; Wells, Peter P.

    2016-01-01

    Copper and zinc form an important group of hydroxycarbonate minerals that include zincian malachite, aurichalcite, rosasite and the exceptionally rare and unstable-and hence little known and largely ignored-georgeite. The first three of these minerals are widely used as catalyst precursors...... for the industrially important methanol-synthesis and low-temperature water-gas shift (LTS) reactions, with the choice of precursor phase strongly influencing the activity of the final catalyst. The preferred phase is usually zincian malachite. This is prepared by a co-precipitation method that involves the transient...

  15. Ionospheric parameters as the precursors of disturbed geomagnetic conditions

    Science.gov (United States)

    Blagoveshchensky, D. V.; Sergeeva, M. A.; Kozlovsky, A.

    2017-12-01

    Geomagnetic storms and substorms are the principal elements of the disturbed Space Weather conditions. The aim of the study was to reveal the ionospheric precursors that can be used to forecast geomagnetic disturbance beginning. To study the ionospheric processes before, during and after magnetic storms and substorms data from Sodankylä Geophysical Observatory was used (geomagnetic coordinates: 64.1oN, 119.2oE). In earlier works the Main Effect (ME) was revealed for substorms. It consists of the following steps: (a) the increase of critical frequency foF2 from its quiet median before and during the substorm growth phase, four-five hours before To moment that is the moment of the expansion phase onset, (b) the foF2 decrease to the level lower than its median just after To and until Te that is the moment of the end of the expansion phase, (c) the issue ;a; repeated during the recovery phase (d) two bell-shape spikes in the cutoff frequency values foEs: first spike occurs three hours before To, second spike - during the expansion phase within the interval between To and Te. In the present work it is shown that ME manifestations can be used as precursors of magnetic substorms at high-latitudes (geomagnetic latitudes 50oN-65oN). In particular, the foF2 growth some hours before To can be used as a precursor of substorm development. The first foEs bell-shaped spike also can be used for short-term forecasting, two-three hours in advance of a substorm. Furthermore, the storms between 2008 and 2012 were studied. It was revealed that the similar ME also takes place in the case of magnetic storms but within the different time scale. More specifically, the first ME maximum in foF2 values occurs one-two days before the storm beginning and can be used as its precursor. In addition, the foEs spike takes place approximately ten hours before a storm and also can be used for the prediction of the storm beginning.

  16. Laser damage in optical components: metrology, statistical and photo-induced analysis of precursor centres

    International Nuclear Information System (INIS)

    Gallais, L.

    2002-11-01

    This thesis deals with laser damage phenomena for nanosecond pulses, in optical components such as glasses, dielectric and metallic thin films. Firstly, a work is done on the laser damage metrology, in order to obtain accurate and reliable measurement of laser-induced damage probabilities, with a rigorous control of test parameters. Then, with the use of a specific model, we find densities of laser damage precursors in the case of bulk glasses (few tens by (100μm) 3 ) and in the case of glass surfaces (one precursor by μm 3 ). Our analysis is associated to morphology studies by Atomic Force Microscope to discuss about precursor nature and damage process. Influence of wavelength (from 355 to 1064 nm) and cumulated shots is also studied. Simulations are performed to study initiation mechanisms on these inclusions. This work gives an estimation of complex index and size of the precursor, which permits to discuss about possible detection by non-destructive tools. (author)

  17. Possible precursors to the 2011 3/11 Japan earthquake:

    Science.gov (United States)

    Hayakawa, M.; Hobara, Y.; Schekotov, A.; Rozhnoi, A.; Solovieva, M.

    2012-04-01

    The purpose of this paper is to present a possible precursor to the 2011 March 11 Japan earthquake. First of all, we present the results on subionospheric VLF/LF propagation anomaly (ionospheric perturbation) by means of Japan-Russia VLF network. It is found that the ionospheric perturbation is clearly detected on March 4, 5 and 6 on the propagation paths of NLK (Seattle, USA) to Japanese stations and on a path of JJI (Miyazaki, Kyushu) to Kamchatka. Next, we present the results on the ULF depression (horizontal component) on the same days, which is interpreted in terms of the absorption in the disturbed lower ionosphere of the downgoing magnetospheric Alfve'n waves. These two precursors are considered to be due to the same effect of the lower ionospheric perturbation about one week before the earthquake.

  18. PREPARATION OF TANTALUM CARBIDE FROM AN ORGANOMETALLIC PRECURSOR

    Directory of Open Access Journals (Sweden)

    C. P. SOUZA

    1999-03-01

    Full Text Available In this work we have synthesized an organometallic oxalic precursor from tantalum oxide. This oxide was solubilized by heating with potassium hydrogen sulfate. In order to precipitate Ta2O5.nH2O, the fused mass obtained was dissolved in a sulfuric acid solution and neutralized with ammonia. The hydrated tantalum oxide precipitated was dissolved in an equimolar solution of oxalic acid/ammonium oxalate. The synthesis and the characterization of the tantalum oxalic precursor are described. Pyrolysis of the complex in a mixture of hydrogen and methane at atmospheric pressure was studied. The gas-solid reaction made it possible to obtain tantalum carbide, TaC, in the powder form at 1000oC. The natural sintering of TaC powder in an inert atmosphere at 1400°C during 10 hours, under inert atmosphere made it possible to densify the carbide to 96% of the theoretical value.

  19. Antarctic new particle formation from continental biogenic precursors

    Directory of Open Access Journals (Sweden)

    E.-M. Kyrö

    2013-04-01

    Full Text Available Over Antarctica, aerosol particles originate almost entirely from marine areas, with minor contribution from long-range transported dust or anthropogenic material. The Antarctic continent itself, unlike all other continental areas, has been thought to be practically free of aerosol sources. Here we present evidence of local aerosol production associated with melt-water ponds in continental Antarctica. We show that in air masses passing such ponds, new aerosol particles are efficiently formed and these particles grow up to sizes where they may act as cloud condensation nuclei (CCN. The precursor vapours responsible for aerosol formation and growth originate very likely from highly abundant cyanobacteria Nostoc commune (Vaucher communities of local ponds. This is the first time freshwater vegetation has been identified as an aerosol precursor source. The influence of the new source on clouds and climate may increase in future Antarctica, and possibly elsewhere undergoing accelerating summer melting of semi-permanent snow cover.

  20. Antarctic new particle formation from continental biogenic precursors

    Science.gov (United States)

    Kyrö, E.-M.; Kerminen, V.-M.; Virkkula, A.; Dal Maso, M.; Parshintsev, J.; Ruíz-Jimenez, J.; Forsström, L.; Manninen, H. E.; Riekkola, M.-L.; Heinonen, P.; Kulmala, M.

    2013-04-01

    Over Antarctica, aerosol particles originate almost entirely from marine areas, with minor contribution from long-range transported dust or anthropogenic material. The Antarctic continent itself, unlike all other continental areas, has been thought to be practically free of aerosol sources. Here we present evidence of local aerosol production associated with melt-water ponds in continental Antarctica. We show that in air masses passing such ponds, new aerosol particles are efficiently formed and these particles grow up to sizes where they may act as cloud condensation nuclei (CCN). The precursor vapours responsible for aerosol formation and growth originate very likely from highly abundant cyanobacteria Nostoc commune (Vaucher) communities of local ponds. This is the first time freshwater vegetation has been identified as an aerosol precursor source. The influence of the new source on clouds and climate may increase in future Antarctica, and possibly elsewhere undergoing accelerating summer melting of semi-permanent snow cover.

  1. Narrativas sobre género y sexualidad en médicos mexicanos. Sus implicaciones sobre las regulaciones corporales, sexuales y reproductivas

    Directory of Open Access Journals (Sweden)

    Itzel A. Sosa-Sánchez

    Full Text Available Resumen A partir de un estudio cualitativo, exploramos los vínculos entre discursos médicos sobre género y sexualidad, y las regulaciones corporales, sexuales y reproductivas en los espacios de salud reproductiva. Entrevistamos a médicos de servicios públicos de salud en México e indagamos sobre las prácticas reproductivas y sexuales de las usuarias, así como sobre las asignaciones sociales y profesionales de cuidado del cuerpo en las relaciones sexuales. Los testimonios revelan cómo los discursos y normatividades sobre género y sexualidad legitiman, en los espacios de salud reproductiva, las desigualdades sociales, especialmente las de género, y la doble moral sexual imperantes en la sociedad mexicana. Las mujeres emergen como saturadas de una sexualidad “desordenada” que debe ser controlada a través de diversas regulaciones corporales, sexuales y reproductivas. Estas regulaciones inciden en el reconocimiento de su autonomía sexual y reproductiva, e impactan negativamente en sus derechos.

  2. Patterned YBa2Cu3O7-x thin films from photopolymerizable precursors

    International Nuclear Information System (INIS)

    Hung, Y.; Agostinelli, J.A.

    1990-01-01

    A technique which combines the fabrication and patterning of thin films of the high T c superconductor YBa 2 Cu 3 O 7-x has been developed. The technique possesses the essential features of the metalorganic decomposition method with the additional attribute that the metalorganic precursor is photopolymerizable. Patterns are generated directly in the precursor film using optical exposure through a mask followed by development in a solvent. A subsequent thermal treatment transforms the patterned precursor film to the oriented superconducting phase with c axis perpendicular to the substrate surface. Resistivity measurements for such a patterned film on a single crystal (100)MgO substrate show an onset to the superconducting state occurring at 85 K with zero resistivity below 67 K

  3. Psychometric properties of the School Anxiety Inventory-Short Version in Spanish secondary education students.

    Science.gov (United States)

    García-Fernández, José M; Inglés, Cándido J; Marzo, Juan C; Martínez-Monteagudo, María C

    2014-05-01

    The School Anxiety Inventory (SAI) can be applied in different fields of psychology. However, due to the inventory's administration time, it may not be useful in certain situations. To address this concern, the present study developed a short version of the SAI (the SAI-SV). This study examined the reliability and validity evidence drawn from the scores of the School Anxiety Inventory-Short Version (SAI-SV) using a sample of 2,367 (47.91% boys) Spanish secondary school students, ranging from 12 to 18 years of age. To analyze the dimensional structure of the SAI-SV, exploratory and confirmatory factor analyses were applied. Internal consistency and test-retest reliability were calculated for SAI-SV scores. A correlated three-factor structure related to school situations (Anxiety about Aggression, Anxiety about Social Evaluation, and Anxiety about Academic Failure) and a three-factor structure related to the response systems of anxiety (Physiological Anxiety, Cognitive Anxiety, and Behavioral Anxiety) were identified and supported. The internal consistency and test-retest reliability were determined to be appropriate. The reliability and validity evidence based on the internal structure of SAI-SV scores was satisfactory.

  4. Plasma glutamine is a minor precursor for the synthesis of citrulline: A multispecies study

    Science.gov (United States)

    Glutamine is considered the main precursor for citrulline synthesis in many species, including humans. The transfer of 15N from 2[15N]-glutamine to citrulline has been used as evidence for this precursor-product relationship. However, work in mice has shown that nitrogen and carbon tracers follow di...

  5. Improved method for measuring transparent exopolymer particles (TEP) and their precursors infresh and saline water

    KAUST Repository

    Villacorte, Loreen O.

    2015-03-01

    Transparent exopolymer particles (TEP) and their precursors produced by phyto-/bacterio-planktons in fresh and marine aquatic environments are increasingly considered as a major contributor to organic/particulate and biological fouling in micro-/ultra-filtration and reverse osmosis membrane (RO) systems. However, currently established methods which are based on Alcian blue (AB) staining and spectrophotometric techniques do not measure TEP-precursors and have the tendency to overestimate concentration in brackish/saline water samples due to interference of salinity on AB staining. Here we propose a new semi-quantitative method which allows measurement of both TEP and their colloidal precursors without the interference of salinity. TEP and their precursors are first retained on 10kDa membrane, rinsed with ultra-pure water, and re-suspended in ultra-pure water by sonication and stained with AB, followed by exclusion of TEP-AB precipitates by filtration and absorbance measurement of residual AB. The concentration is then determined based on the reduction of AB absorbance due to reaction with acidic polysaccharides, blank correction and calibration with Xanthan gum standard. The extraction procedure allows concentration of TEP and their pre-cursors which makes it possible to analyse samples with a wide range of concentrations (down to <0.1mg Xeq/L). This was demonstrated through application of the method for monitoring these compounds in algal cultures and a full-scale RO plant. The monitoring also revealed that concentrations of the colloidal precursors were substantially higher than the concentration of TEP themselves. In the RO plant, complete TEP removal was observed over the pre-treatment processes (coagulation-sedimentation-filtration and ultrafiltration) but the TEP precursors were not completely removed, emphasising the importance of measuring this colloidal component to better understand the role of TEP and acidic polysaccharides in RO membrane fouling.

  6. A origem da salinidade no Continente Antártico The origin of salinity in the Antarctic Continent

    Directory of Open Access Journals (Sweden)

    Arcângelo Loss

    2010-12-01

    Full Text Available A Antártica é o mais perfeito laboratório natural do planeta para estudos de mudanças ambientais. Partindo dessa premissa, este estudo teve como objetivo realizar uma revisão sobre a origem dos sais presentes no continente antártico, sendo pormenorizado as principais formas e fontes salinas que ocorrem. Na literatura, este tema é de grande discussão, sendo relatado que a origem dos sais pode ser devido à precipitação atmosférica, intemperismo de rochas, origem marinha (spray salino, sulfatos biologicamente produzidos ou atividade hidrotermal. De maneira geral, a presente revisão permitiu inferir diversas origens dos sais solúveis em água nos solos da Antártica. Perto da costa, influências marinhas são dominantes, encobrindo quaisquer contribuições do intemperismo das rochas. Mas para o interior, a influência do intemperismo é mais evidente, ao passo que a influência de circulação atmosférica superior torna-se importante também. Ressalta-se também, a importância da contribuição continental no aporte de sais nos períodos glaciais.The Antarctica is the most perfect natural laboratory to study the planet from environmental changes. From this premise, this study was to conduct a review on the origin of salts in the Antarctic, and detailed the main forms and sources occurring salt. In literature, this topic is of great discussion, and reported that the origin of salts may be due to precipitation, rock weathering, marine (salt spray, biologically produced sulfates or hydrothermal activity. Overall, this review allows us to infer various sources of water-soluble salts in soils of Antarctica. Near the coast, marine influences are dominant, covering up any contributions from weathering of rocks. But for the interior, the influence of weathering is more evident, while the influence of atmospheric circulation becomes more important as well. We also emphasize the importance of the contribution in the continental input of salts

  7. Natural Organochlorines as Precursors of 3-Monochloropropanediol Esters in Vegetable Oils.

    Science.gov (United States)

    Tiong, Soon Huat; Saparin, Norliza; Teh, Huey Fang; Ng, Theresa Lee Mei; Md Zain, Mohd Zairey Bin; Neoh, Bee Keat; Md Noor, Ahmadilfitri; Tan, Chin Ping; Lai, Oi Ming; Appleton, David Ross

    2018-01-31

    During high-temperature refining of vegetable oils, 3-monochloropropanediol (3-MCPD) esters, possible carcinogens, are formed from acylglycerol in the presence of a chlorine source. To investigate organochlorine compounds in vegetable oils as possible precursors for 3-MCPD esters, we tested crude palm, soybean, rapeseed, sunflower, corn, coconut, and olive oils for the presence of organochlorine compounds. Having found them in all vegetable oils tested, we focused subsequent study on oil palm products. Analysis of the chlorine isotope mass pattern exhibited in high-resolution mass spectrometry enabled organochlorine compound identification in crude palm oils as constituents of wax esters, fatty acid, diacylglycerols, and sphingolipids, which are produced endogenously in oil palm mesocarp throughout ripening. Analysis of thermal decomposition and changes during refining suggested that these naturally present organochlorine compounds in palm oils and perhaps in other vegetable oils are precursors of 3-MCPD esters. Enrichment and dose-response showed a linear relationship to 3-MCPD ester formation and indicated that the sphingolipid-based organochlorine compounds are the most active precursors of 3-MCPD esters.

  8. Nondestructive Examination (NDE) Detection and Characterization of Degradation Precursors, Technical Progress Report for FY 2012

    Energy Technology Data Exchange (ETDEWEB)

    Ramuhalli, P.; Meyer, R.M.; Fricke, J.M.; Prowant, M.S.; Coble, J.B.; Griffin, J.W.; Pitman, S.G.; Dahl, M.E.; Kafentzis, T.A.; Roosendaal, T.J.

    2012-09-01

    The overall objective of this project was to investigate the effectiveness of nondestructive examination (NDE) technology in detecting material degradation precursors by initiating and growing cracks in selected materials and using NDE methods to measure crack precursors prior to the onset of cracking. Nuclear reactor components are subject to stresses over time that are not precisely known and that make the life expectancy of components difficult to determine. To prevent future issues with the operation of these plants because of unforeseen failure of components, NDE technology is needed that can be used to identify and quantify precursors to macroscopic degradation of materials. Some of the NDE methods being researched as possible solutions to the precursor detection problem are magnetic Barkhausen noise, nonlinear ultrasonics, acoustic emission, eddy current measurements, and guided wave technology. In FY12, the objective was to complete preliminary assessment of advanced NDE techniques for sensitivity to degradation precursors, using prototypical degradation mechanisms in laboratory-scale measurements. This present document reports on the deliverable that meets the following milestone: M3LW-12OR0402143 – Report detailing an initial demonstration on samples from the crack-initiation tests will be provided (demonstrating acceleration of the work).

  9. Xylopia Aethiopica lowers Plasma Lipid Precursors of Reproductive ...

    African Journals Online (AJOL)

    Xylopia Aethiopica lowers Plasma Lipid Precursors of Reproductive Hormones in Wister Rats. PC Onyebuagu, CP Aloamaka, JC Igweh. Abstract. This study investigated the effects of dietary Xylopia aethiopica on reproductive hormones and plasma lipids in rats. 10 male and 10 female Wistar rats weighing 200-220g and ...

  10. An effective approach to synthesize monolayer tungsten disulphide crystals using tungsten halide precursor

    Energy Technology Data Exchange (ETDEWEB)

    Thangaraja, Amutha; Shinde, Sachin M.; Kalita, Golap, E-mail: kalita.golap@nitech.ac.jp; Tanemura, Masaki [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan)

    2016-02-01

    The synthesis of large-area monolayer tungsten disulphide (WS{sub 2}) single crystal is critical for realistic application in electronic and optical devices. Here, we demonstrate an effective approach to synthesize monolayer WS{sub 2} crystals using tungsten hexachloride (WCl{sub 6}) as a solid precursor in atmospheric chemical vapor deposition process. In this technique, 0.05M solution of WCl{sub 6} in ethanol was drop-casted on SiO{sub 2}/Si substrate to create an even distribution of the precursor, which was reduced and sulfurized at 750 °C in Ar atmosphere. We observed growth of triangular, star-shaped, as well as dendritic WS{sub 2} crystals on the substrate. The crystal geometry evolves with the shape and size of the nuclei as observed from the dendritic structures. These results show that controlling the initial nucleation and growth process, large WS{sub 2} single crystalline monolayer can be grown using the WCl{sub 6} precursor. Our finding shows an easier and effective approach to grow WS{sub 2} monolayer using tungsten halide solution-casting, rather than evaporating the precursor for gas phase reaction.

  11. Disinfection by-products/precursor control using an innovative treatment process -- high energy electron beam irradiation

    International Nuclear Information System (INIS)

    Sawal, K.; Millington, B.; Slifker, R.A.; Cooper, W.J.; Nickelsen, M.G.; Kurucz, C.N.; Waite, T.D.

    1993-01-01

    When waters containing naturally occurring humic substances, precursors, are chlorinated, reaction (disinfection) by-products (DBPs) that may compromise the chemical water quality of the drinking water are formed. Two options exist for the treatment of THMs and other DBPs, removal of precursor material prior to chlorination, or destruction of the by-products once they are formed. The authors have initiated a study using an innovative process, high energy electron beam irradiation, as an alternative treatment for the destruction of toxic organic compounds. Preliminary studies indicated that the process would also be effective in the removal of precursors. An added advantage of this process is that is would serve as a primary disinfectant, destroying any toxic compounds in the source water and may assist in the removal of algae and cyanobacteria toxins. This paper discusses studies in precursor removal and control of THMs

  12. Revisitando uma carta em português sobre Sabbatai Zvi

    Directory of Open Access Journals (Sweden)

    Rodrigues da Silva Tavim, José Alberto

    2007-06-01

    Full Text Available The present paper deals with the Iberian context of the production-translation of a text in Portuguese language about Shabbatai Zevi, in 1666. We refer the production of similar texts and the information about the adherents in Spain, mostly in Malaga. We reflect on the various messsianic currents that crossed the different social groups in Portugal. We present a text that proves the spreading of news about Shabbatai in Portuguese Lands, and the interest kindled among the Portuguese Conversos. And we place the hypothesis that this text to the movement of Shabbatai, could have different readings, among them one that could be convenient to the conversos.

    Este artículo aborda el contexto de la producción-traducción de un texto en portugués sobre Sabetay Sebí, en 1666. Se alude a la producción de otros textos similares y a la información sobre los adeptos del movimiento en España, sobre todo en Málaga. Se reflexiona sobre las varias corrrientes mesiánicas que cruzaban los diferentes grupos sociales en Portugal. Se presenta un texto que prueba la divulgación de noticias sobre Sabetay, en tierras portuguesas y del interés desperttado entre los medios conversos sobre el movimiento. Y se plantea la hipótesis de que este texto contrario al movimiento de Sabbatai pudiera tener varias lecturas, entre ellas una que debería ser conveniente para los conversos.

  13. The formation of CuInSe{sub 2}-based thin-film solar cell absorbers from alternative low-cost precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jost, S.

    2008-01-18

    This work deals with real-time investigations concerning the crystallisation process of CuInSe{sub 2}-based thin-film solar cell absorbers while annealing differently produced and composed ''low-cost'' precursors. Various types of precursors have been investigated concerning their crystallisation behaviour. Three groups of experiments have been performed: (i) Investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} and Cu(In,Al)S{sub 2}, (ii) investigations concerning the formation process of the compound semiconductor CuInSe{sub 2} from electroplated precursors, and (iii) investigations concerning the crystallisation of Cu(In,Ga)Se{sub 2} using precursors with thermally evaporated indium. A specific sample surrounding has been constructed, which enables to perform time-resolved angle-dispersive X-ray powder diffraction experiments during the annealing process of precursor samples. A thorough analysis of subsequently recorded diffraction patterns using the Rietveld method provides a detailed knowledge about the semiconductor crystallisation process while annealing. Based on these fundamental investigations, conclusions have been drawn concerning an adaptation of the precursor deposition process in order to optimise the final solar cell results. The investigations have shown, that one class of electroplated precursors shows a crystallisation behaviour identical to the one known for vacuum-deposited precursors. The investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} revealed, that the chalcopyrite forms from the ternary selenide (Al,In){sub 2}Se{sub 3} and Cu{sub 2}Se at elevated process temperatures. This result is used to explain the separation of the absorber layer into an aluminum-rich and an indium-rich chalcopyrite phase, which has been observed at processed Cu(In,Al)Se{sub 2} absorbers from several research groups. In addition, differences

  14. Structural phase transition and precursor phenomena in V3Si

    International Nuclear Information System (INIS)

    Kobayashi, T.; Fukase, T.; Toyota, N.; Muto, Y.

    1982-01-01

    Thermal dilation experiments on the transforming single crystals V 3 Si indicated that the precursor of the structural transformation at Tsub(m) of about 21 K starts at anomalously high temperatures (proportional70 K) and grows drastically near Tsub(m). This anomaly is also accompanied by the critical increment of electrical resistivity showing a sharp peak at Tsub(m). The application of the uniaxial stress suppresses the resistivity anomaly and makes the superconducting transition width narrower. We propose a model for the precursor phenomena in terms of (1) the directional strain fields (non-cubic) pinned near the defects and (2) the memory effect of orientation of the tetragonal domains born by the defects such as dislocations. (orig.)

  15. Precursor and Neutral Loss Scans in an RF Scanning Linear Quadrupole Ion Trap

    Science.gov (United States)

    Snyder, Dalton T.; Szalwinski, Lucas J.; Schrader, Robert L.; Pirro, Valentina; Hilger, Ryan; Cooks, R. Graham

    2018-03-01

    Methodology for performing precursor and neutral loss scans in an RF scanning linear quadrupole ion trap is described and compared to the unconventional ac frequency scan technique. In the RF scanning variant, precursor ions are mass selectively excited by a fixed frequency resonance excitation signal at low Mathieu q while the RF amplitude is ramped linearly to pass ions through the point of excitation such that the excited ion's m/z varies linearly with time. Ironically, a nonlinear ac frequency scan is still required for ejection of the product ions since their frequencies vary nonlinearly with the linearly varying RF amplitude. In the case of the precursor scan, the ejection frequency must be scanned so that it is fixed on a product ion m/z throughout the RF scan, whereas in the neutral loss scan, it must be scanned to maintain a constant mass offset from the excited precursor ions. Both simultaneous and sequential permutation scans are possible; only the former are demonstrated here. The scans described are performed on a variety of samples using different ionization sources: protonated amphetamine ions generated by nanoelectrospray ionization (nESI), explosives ionized by low-temperature plasma (LTP), and chemical warfare agent simulants sampled from a surface and analyzed with swab touch spray (TS). We lastly conclude that the ac frequency scan variant of these MS/MS scans is preferred due to electronic simplicity. In an accompanying manuscript, we thus describe the implementation of orthogonal double resonance precursor and neutral loss scans on the Mini 12 using constant RF voltage. [Figure not available: see fulltext.

  16. REPRESENTAÇÃO SOCIAL DOS ENFERMEIROS SOBRE CUIDADOS PALIATIVOS

    OpenAIRE

    Coelho de Britto, Sabrina Maria; de Souza Ramos, Raquel; dos Santos, Érick Igor; da Silva Veloso, Olga; Melo da Silva, Aline; de Aguiar Mariz, Rosângela Guiomar

    2015-01-01

    Introdução: O presente estudo refere-se a um processo de investigação sobre a representação social dos enfermeiros sobre cuidados paliativos. Objetivos: identificar a estrutura das representações sociais dos enfermeiros sobre cuidados paliativos; discutir as repercussões dessas representações no cotidiano da prática assistencial. Materiais e Métodos: Para a realização deste estudo foram abordados 70 enfermeiros que atuam nas enfermarias do serviço de Clínica Médica. A técnica para coleta de d...

  17. Study of a sol–gel precursor and its evolution towards ZnO

    Energy Technology Data Exchange (ETDEWEB)

    Gómez-Núñez, Alberto [University of Barcelona, Department of Electronics, Martí i Franquès 1, E08028 Barcelona (Spain); López, Concepción [University of Barcelona, Department of Inorganic Chemistry, Martí i Franquès 1, E08028 Barcelona (Spain); Alonso-Gil, Santiago [University of Barcelona, Department of Organic Chemistry, Martí i Franquès 1, E08028 Barcelona (Spain); Roura, Pere [University of Girona, Department of Physics, Campus Montilivi, Edif. PII, E17071 Girona (Spain); Vilà, Anna, E-mail: anna.vila@ub.edu [University of Barcelona, Department of Electronics, Martí i Franquès 1, E08028 Barcelona (Spain)

    2015-07-15

    The processes involved in the assembly of zinc acetate dihydrate {Zn(CH_3COO)_2·2H_2O} and ethanolamine (H{sub 2}NCH{sub 2}CH{sub 2}OH), with or without 2-methoxyethanol as solvent, have been analysed by infrared spectra, mass spectrometry, nuclear magnetic resonance, powder X-ray diffraction and computational studies. Thermal evolution of the mixtures was characterized by thermoanalytical and structural techniques (thermogravimetry, differential thermal analysis, differential scanning calorimetry, X-ray diffraction and X-Ray photoelectron spectroscopy). Computational studies together with experiments served to thoroughly describe the precursor and its decomposition. The thermal decomposition of the mixture and its transformation into crystalline ZnO take place in a temperature range between 50 and 450 °C through different processes. With solvent, the processes need temperatures 90 °C higher with respect to the mixture without solvent, and ZnO arises at 250 °C. - Graphical abstract: Display Omitted - Highlights: • Tetramer structure of the zinc-acetate plus ethanolamine precursor confirmed by IR, MS and theoretical calculations. • Precursor crystal structure determined to be of the monoclinic P2{sub 1}/m system. • High influence of the metoxyethanol solvent on the formation temperature of ZnO. • Detailed description of the thermal evolution from the zinc-based precursor to ZnO.

  18. Precursor/product studies of macrophage synthesis of nitrite, nitrate and N-nitrosamines

    International Nuclear Information System (INIS)

    Iyengar, R.; Marletta, M.A.

    1987-01-01

    Previous experiments showed that nitrite, nitrate and N-nitrosamine synthesis was carried out by both stimulated macrophages (M phi) and a number of M phi cell lines. Here the authors report the precursor to NO 2 - , NO 3 - , and the source of the nitrosating agent. Previous kinetic studies established a time lag for NO 2 - /NO 3 - synthesis during which protein synthesis required for product formation occurred. Medium change after the protein synthesis phase showed that L-arginine was the only amino acid essential for the synthesis. Other precursors were homoarginine, arginine methyl ester, arginine infinity-hydroxamate, argininamide and the peptide arginine-aspartate. Glutamine, citrulline, ornithine, hydroxylamine and D-arginine were among some of the non-precursors. Canavanine though not a precursor inhibited arginine-derived NO 2 -/NO 3 - synthesis while D-arginine had no effect. When 15 N-arginine (guanido- 15 N 2 , 95%) was used, GC/MS results showed that all the NO 2 - /NO 3 - synthesized was derived exclusively from these two guanido nitrogens. Similar labeling experiments carried out in the presence of morpholine showed that the isotopic enrichment of N-nitrosomorpholine was the same as that of NO 2 - /NO 3 - synthesized, suggesting that the nitrosating agent is a common intermediate. In conclusion, NO 2 - /NO 3 - and N-nitrosomorpholine synthesis by stimulated macrophages is derived specifically from the two guanido nitrogens of arginine

  19. Some peculiarities of zirconium tungstate synthesis by thermal decomposition of hydrothermal precursors

    International Nuclear Information System (INIS)

    Gubanov, Alexander I.; Dedova, Elena S.; Plyusnin, Pavel E.; Filatov, Eugeny Y.; Kardash, Tatyana Y.; Korenev, Sergey V.; Kulkov, Sergey N.

    2014-01-01

    Highlights: • Synthesis of ZrW 2 O 8 using hydrothermal method. • On hydrothermal synthesis optimal conc. of HCl in the reaction mixture is 2.3 M. • Thermal decomposition of ZrW 2 O 7 ((OH) 1.5 ,Cl 0.5 )·2H 2 O begins are 200 °S. • Amorphous intermediate crystallizes into cubic single-phase ZrW 2 O 8 above 550 °S. • ZrW 2 O 8 destructed at temperatures above 700 °S. - Abstract: This article discusses some peculiarities of the synthesis of ZrW 2 O 8 (1) using thermal decomposition of the precursor ZrW 2 O 7 ((OH) 1.5 ,Cl 0.5 )·2H 2 O (2) prepared by hydrothermal method. On hydrothermal synthesis of 2 the optimal concentration of hydrochloric acid in the reaction mixture is about 2.3 M. TG approach to determine the chemical composition of the precursor was suggested. It has been found that the precursor for the synthesis of zirconium tungstate has chemical formula 2. Thermal decomposition of the precursor 2 begins at 200 °S and affords an amorphous intermediate, which crystallizes as a cubic phase 1 above 550 °S with an exoeffect. The temperature of the beginning of the transition from amorphous to the crystalline state is 350 ± 25 °S

  20. Estudos sobre a Esquistosomose em Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    Aggeu Magalhães

    1940-01-01

    Full Text Available Os autores referem os resultados dos estudos sobre esquistosomose realisados, em Pernambuco, de Novembro de 1938 a Dezembro de 1939. Não se extendem em discussão, nem comentarios, tampouco, relacionam suas verificações com o que já foi relatado sobre o assunto em trabalhos nacionais e estrangeiros, pelo fato de que, não se trata de um resultado definitivo e sim de atividades que irão proseguir. Os estudos sistematicos em torno da endemia esquistosomica foram executados em duas localidades diversas pela população e pela situação geografica e ecologica. Pontezinha é uma povoação de 1200 habitantes localizada proximo a um conjunto de charcos e lagõas de agua dôce onde pululam caramujos do tipo olivaceus de Spix, e apresenta uma taxa de infestação de 21,4% para individuos do sexo masculino, e de 14,7% para os do sexo feminino. A distribuição por grupos de idade mostra que a incidencia cresce até o grupo de 16 a 20 anos de idade, quando atinge a percentagem de 37,8%, para decrescer em seguida. Em Vitoria a incidencia foi maior nos indivíduos do sexo feminino, atingindo a taxa de 41,4%, dando o sexo masculino a taxa de 36,9%. Por idade a percentagem maxima é atingida pelo grupo de 11 a 15 anos. Vitoria é uma cidade de 1500 habitantes, construida á margem do rio Tapacurá, onde se encontram numerosos caramujos do tipo centimetralis Lutz. A divergencia de incidencia corre por conta dos habitos da população e pela utilização que ela faz do rio, sendo maior em Vitoria porque a proximidade do rio facilita o uso de suas aguas para banho e serviços domesticos, condicionando este ultimo fato, a maior infestação das mulheres. O estudo da frequencia da infestação dos caramujos por cercarias de diversos trematodios, permite suspeitar uma relação inversa entre a taxa de infestação e o diametro maximo atingido pelos caramujos, parecendo este fato confirmar os trabalhos de Vianna Martins sobre a identidade dos hospedeiros

  1. Precursor Wave Emission Enhanced by Weibel Instability in Relativistic Shocks

    Science.gov (United States)

    Iwamoto, Masanori; Amano, Takanobu; Hoshino, Masahiro; Matsumoto, Yosuke

    2018-05-01

    We investigated the precursor wave emission efficiency in magnetized purely perpendicular relativistic shocks in pair plasmas. We extended our previous study to include the dependence of upstream magnetic field orientations. We performed two-dimensional particle-in-cell simulations and focused on two magnetic field orientations: the magnetic field in the simulation plane (i.e., in-plane configuration) and that perpendicular to the simulation plane (i.e., out-of-plane configuration). Our simulations in the in-plane configuration demonstrated that not only extraordinary but also ordinary mode waves are excited. We quantified the emission efficiency as a function of the magnetization parameter σ e and found that the large-amplitude precursor waves are emitted for a wide range of σ e . We found that especially at low σ e , the magnetic field generated by Weibel instability amplifies the ordinary mode wave power. The amplitude is large enough to perturb the upstream plasma, and transverse density filaments are generated as in the case of the out-of-plane configuration investigated in the previous study. We confirmed that our previous conclusion holds regardless of upstream magnetic field orientations with respect to the two-dimensional simulation plane. We discuss the precursor wave emission in three dimensions and the feasibility of wakefield acceleration in relativistic shocks based on our results.

  2. PRECURSORS OF EARTHQUAKES: VLF SIGNALSIONOSPHERE IONOSPHERE RELATION

    Directory of Open Access Journals (Sweden)

    Mustafa ULAS

    2013-01-01

    Full Text Available lot of people have died because of earthquakes every year. Therefore It is crucial to predict the time of the earthquakes reasonable time before it had happed. This paper presents recent information published in the literature about precursors of earthquakes. The relationships between earthquakes and ionosphere are targeted to guide new researches in order to study further to find novel prediction methods.

  3. A review on remotely sensed land surface temperature anomaly as an earthquake precursor

    Science.gov (United States)

    Bhardwaj, Anshuman; Singh, Shaktiman; Sam, Lydia; Joshi, P. K.; Bhardwaj, Akanksha; Martín-Torres, F. Javier; Kumar, Rajesh

    2017-12-01

    The low predictability of earthquakes and the high uncertainty associated with their forecasts make earthquakes one of the worst natural calamities, capable of causing instant loss of life and property. Here, we discuss the studies reporting the observed anomalies in the satellite-derived Land Surface Temperature (LST) before an earthquake. We compile the conclusions of these studies and evaluate the use of remotely sensed LST anomalies as precursors of earthquakes. The arrival times and the amplitudes of the anomalies vary widely, thus making it difficult to consider them as universal markers to issue earthquake warnings. Based on the randomness in the observations of these precursors, we support employing a global-scale monitoring system to detect statistically robust anomalous geophysical signals prior to earthquakes before considering them as definite precursors.

  4. Sobre-educación en el mercado laboral colombiano

    Directory of Open Access Journals (Sweden)

    Jhon James Mora

    2008-12-01

    Full Text Available Este artículo analiza la sobre-educación en Colombia con datos de individuos y empresas compilados por el Servicio Nacional de Aprendizaje de Colombia en 2006, encuentra que la probabilidad de estar sobre-educado es del 14% y que depende de la movilidad entre áreas de desempeño, la experiencia, el género, el tamaño de la empresa y el nivel de educación. Los trabajadores sobre-educados ganan un 2% menos que los trabajadores correctamente educados, conforme al patrón internacional. Los resultados también muestran que la probabilidad de que los profesionales permanezcan en la misma área de desempeño aumenta con la experiencia, que cuanto mayor es la sobre-educación menor es la probabilidad de permanecer en dicha área y que los trabajadores con postgrado tienen menor probabilidad de permanecer en su área de desempeño.

  5. Consideraciones del bioderecho sobre la eutanasia en Colombia

    Directory of Open Access Journals (Sweden)

    José Antonio García Pereáñez

    2017-01-01

    Full Text Available Este artículo aborda de manera reflexiva las incidencias del bioderecho sobre situaciones de eutanasia en Colombia, al interpretar conflictos morales y jurídicos suscitados por las sentencias de la Corte Constitucional C239 de 1997, T970 de 2014 y la Resolución del Ministerio de Salud y Protección Social 1216, de 2015. El propósito fundamental es el análisis de las decisiones judiciales sobre el final de la vida humana. Por lo tanto, se realiza una revisión de la construcción histórica y jurídica del concepto de eutanasia y se propone la discusión sobre su manejo jurídico y su influencia en el colectivo moral. Asimismo, se diserta sobre el concepto de dignidad humana y muerte digna, como precedentes para dirimir los conflictos éticos que la eutanasia suscita. Al final, se analiza el caso de don Ovidio González, quien se convirtió en 2015 en el primer colombiano en recibir la eutanasia de manera legal dentro del sistema de salud.

  6. Helper T lymphocyte precursor frequency analysis in alloreactivity detection

    International Nuclear Information System (INIS)

    Cukrova, V.; Dolezalova, L.; Loudova, M.; Vitek, A.

    1998-01-01

    The utility of IL-2 secreting helper T lymphocyte precursors (HTLp) frequency testing has been evaluated for detecting alloreactivity. The frequency of HTLp was approached by limiting dilution assay. High HTLp frequency was detected in 20 out of 30 HLA matched unrelated pairs (67%). The comparison of HTLp and CTLp (cytotoxic T lymphocyte precursors) frequencies in HLA matched unrelated pairs showed that the two examinations are not fully alternative in detecting alloreactivity. This could suggest the utility of combined testing of both HTLp and CTLp frequencies for alloreactivity assessment. In contrast, five positive HTLp values were only found among 28 HLA genotypic identical siblings (18%). Previous CTLp limiting dilution studies showed very low or undetectable CTLp frequency results in that group. For that, HTLp assay remains to be the only cellular in vitro technique detecting alloreactivity in these combinations. (authors)

  7. Structural basis for precursor protein-directed ribosomal peptide macrocyclization

    Science.gov (United States)

    Li, Kunhua; Condurso, Heather L.; Li, Gengnan; Ding, Yousong; Bruner, Steven D.

    2016-01-01

    Macrocyclization is a common feature of natural product biosynthetic pathways including the diverse family of ribosomal peptides. Microviridins are architecturally complex cyanobacterial ribosomal peptides whose members target proteases with potent reversible inhibition. The product structure is constructed by three macrocyclizations catalyzed sequentially by two members of the ATP-grasp family, a unique strategy for ribosomal peptide macrocyclization. Here, we describe the detailed structural basis for the enzyme-catalyzed macrocyclizations in the microviridin J pathway of Microcystis aeruginosa. The macrocyclases, MdnC and MdnB, interact with a conserved α-helix of the precursor peptide using a novel precursor peptide recognition mechanism. The results provide insight into the unique protein/protein interactions key to the chemistry, suggest an origin of the natural combinatorial synthesis of microviridin peptides and provide a framework for future engineering efforts to generate designed compounds. PMID:27669417

  8. Structural basis for precursor protein-directed ribosomal peptide macrocyclization.

    Science.gov (United States)

    Li, Kunhua; Condurso, Heather L; Li, Gengnan; Ding, Yousong; Bruner, Steven D

    2016-11-01

    Macrocyclization is a common feature of natural product biosynthetic pathways including the diverse family of ribosomal peptides. Microviridins are architecturally complex cyanobacterial ribosomal peptides that target proteases with potent reversible inhibition. The product structure is constructed via three macrocyclizations catalyzed sequentially by two members of the ATP-grasp family, a unique strategy for ribosomal peptide macrocyclization. Here we describe in detail the structural basis for the enzyme-catalyzed macrocyclizations in the microviridin J pathway of Microcystis aeruginosa. The macrocyclases MdnC and MdnB interact with a conserved α-helix of the precursor peptide using a novel precursor-peptide recognition mechanism. The results provide insight into the unique protein-protein interactions that are key to the chemistry, suggest an origin for the natural combinatorial synthesis of microviridin peptides, and provide a framework for future engineering efforts to generate designed compounds.

  9. Alkoxide-based precursors for direct drawing of metal oxide micro- and nanofibres

    Energy Technology Data Exchange (ETDEWEB)

    Taette, Tanel; Hussainov, Medhat; Paalo, Madis; Part, Marko; Talviste, Rasmus; Kiisk, Valter; Maendar, Hugo; Pohako, Kaija; Reivelt, Kaido; Lohmus, Ants [Institute of Physics, University of Tartu, Riia 142, Tartu 51014 (Estonia); Pehk, Tonis [National Institute of Chemical and Biological Physics, Akadeemia tee 23, Tallinn 12618 (Estonia); Natali, Marco [ICIS-CNR, Corso Stati Uniti 4, Padova 35127 (Italy); Gurauskis, Jonas [Instituto de Ciencia de Materiales de Aragon C.S.I.C., University of Zaragoza Fac. De Ciencias, c/Pedro Cerbuna 12, Zaragoza 50009 (Spain); Maeeorg, Uno, E-mail: tanelt@fi.tartu.ee [Institute of Chemistry, University of Tartu, Ravila 14a, Tartu 50411 (Estonia)

    2011-06-15

    The invention of electrospinning has solved the problem of producing micro- and nanoscaled metal oxide fibres in bulk quantities. However, until now no methods have been available for preparing a single nanofibre of a metal oxide. In this work, the direct drawing method was successfully applied to produce metal oxide (SnO{sub 2}, TiO{sub 2}, ZrO{sub 2}, HfO{sub 2} and CeO{sub 2}) fibres with a high aspect ratio (up to 10 000) and a diameter as small as 200 nm. The sol-gel processing includes consumption of precursors obtained from alkoxides by aqueous or non-aqueous polymerization. Shear thinning of the precursors enables pulling a material into a fibre. This rheological behaviour can be explained by sliding of particles owing to external forces. Transmission (propagation) of light along microscaled fibres and their excellent surface morphology suggest that metal oxide nanofibres can be directly drawn from sol precursors for use in integrated photonic systems.

  10. NBOMe: perfil de apreensões da Polícia Federal no Brasil

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Yasin Wayhs

    2016-11-01

    Full Text Available A Polícia Federal (PF possui informações importantes sobre as apreensões de drogas sintéticas no país que podem ser compiladas e organizadas para descrever o panorama atual das designer drugs no Brasil sob a realidade observada pela PF. Trata-se do Sistema Criminalística, um banco de dados nacional com laudos periciais digitalizados. Neste contexto, este estudo teve como objetivo fazer um levantamento estatístico do perfil de apreensão das drogas sintéticas que contém NBOMe - grupo derivado da feniletilamina com propriedades alucinógenas - seus sais e isômeros, através da análise dos dados contidos nos relatórios periciais emitidos pela Polícia Federal no Brasil nos últimos 5 anos. As seguintes informações foram coletadas: número de laudos, local das apreensões, local de elaboração dos laudos, formas de apresentação, principais drogas apreendidas em conjunto com NBOMe e suas respectivas formas de apresentação, classificação química do NBOMe - de acordo com substituintes - quantidade de unidades apreendidas e principais imagens visualizadas nos materiais apreendidos pelos agentes federais. Foi possível traçar um panorama da situação nacional atual, sob a ótica da PF, sobre drogas sintéticas para o aprofundamento da visão, especialmente em produtos que contenham NBOMe, seus sais e isômeros. Os dados aqui apresentados se destinam a apoiar as políticas de planejamento de ações estratégicas para o controle, supressão e prevenção de uso de drogas e tráfico.

  11. [13N]ammonia in organic solvents; a potent synthetic precursor for 13N-labeling

    International Nuclear Information System (INIS)

    Tominaga, Toshiyoshi; Hirobe, Masaaki

    1987-01-01

    13 NH 3 in an organic solvent was prepared and its utility as a labeling precursor was studied. [ 13 N]adenine ([ 13 N]ADN), [ 13 N]nicotinamide ([ 13 N]NAM), [ 13 N]p-nitrophenyl carbamate ([ 13 N]NPC), and [ 13 N]L-glutamine ([ 13 N]Gln) were labeled utilizing this precursor. [ 13 N]ADN and [ 13 N]NAM were labeled in much better yields than from an aqueous solution of 13 NH 3 . [ 13 N]NPC and [ 13 N]Gln, which could not be labeled in an aqueous solution, were labeled in high radiochemical yields. Thus, the advantages of this precursor are the improvement of the labeling yield and the feasibility of labeling compounds unstable in aqueous conditions. (author)

  12. Conglomeración de precursores de tensión arterial elevada en adolescentes

    Directory of Open Access Journals (Sweden)

    Carlos M. Arango

    2014-09-01

    Conclusión: La conglomeración de dos o más precursores se asoció de manera significativa con la tensión arterial elevada, hallazgos que indican que se requieren intervenciones para reducir la presencia y acumulación de los precursores estudiados y así prevenir la adquisición de cifras de tensión arterial elevada en los adolescentes de Montería.

  13. Thermal decomposition and spectroscopic investigation of a new aqueous glycolato(-peroxo) Ti(IV) solution-gel precursor

    International Nuclear Information System (INIS)

    De Dobbelaere, Christopher; Mullens, Jules; Hardy, An; Van Bael, Marlies K.

    2011-01-01

    Highlights: → A totally water based glycolato-Ti(IV) precursor is presented and characterized. → The precursors' thermal decomposition profile depends on the ligand to metal ratio. → Titanium is coordinated in an unidentate fashion by the glycolate anion. → Smooth and uniform TiO 2 films can be prepared from the precursor solution. - Abstract: A new aqueous solution-gel precursor based on water soluble glycolato(-peroxo)-Ti(IV) complexes is developed for the preparation of TiO 2 films. With regard to the decomposition of complexes towards oxide formation, it is important to gain insight in the chemical transformations inside the precursor during thermal treatment. Therefore, the thermo-oxidative decomposition pathway of a gel obtained by slow evaporation of the precursor solution is described based on hyphenated thermogravimetric analysis with Fourier transform infrared spectroscopy (TGA-FTIR) and mass spectrometry (TGA-MS). Pure glycolic acid is used as a reference system for this study. By varying the molar glycolic acid to Ti(IV) ratio, the thermal decomposition of the gel can be drastically shortened and the profile's course changed. Gel structure and chemical changes in the gel upon heating are also studied by means of off-line FTIR. A unidentate coordination of the titanium(IV) ion by the carboxylate group of the glycolato ligands and the involvement of the hydroxyl group is confirmed. Phase formation at certain points in the thermal decomposition is studied by X-ray diffraction and Raman spectroscopy. Finally, it is proven that the new precursor is a valuable candidate for the deposition of low carbon containing solution-gel films which can ultimately be converted into smooth and uniform TiO 2 films.

  14. Efeito da técnica de curtimento e do método utilizado para remoção da pele da tilápia-do-nilo sobre as características de resistência do couro Effect of tanning technique and methods used for skin removal on leather resistance characteristics of Nile Tilapia

    Directory of Open Access Journals (Sweden)

    Maria Luiza Rodrigues de Souza

    2006-08-01

    Full Text Available Um estudo foi realizado com o objetivo de avaliar os efeitos do método de remoção da pele do filé (com alicate e com máquina e da técnica de curtimento (com ou sem sais de cromo, bioleather sobre a resistência da pele de tilápia-do-nilo (Oreochromis niloticus. Foram retiradas as peles de 40 tilápias (450 g, 20 com uso de alicates e 20 com auxílio de máquina. Após o curtimento e a retirada dos corpos-de-prova, as peles foram encaminhadas a um laboratório aclimatizado (23ºC e 50% de umidade relativa do ar para realização dos testes de resistência em dinamômetro EMIC, com velocidade de afastamento entre cargas de 100 ± 20 mm/mm. O método de retirada da pele do filé não afetou os resultados dos testes de tração e rasgamento progressivo. A pele retirada com a máquina apresentou elongação superior (88,48% à removida com alicate (71,09%. Peles curtidas com sais de cromo (25,54 N/mm; 12,18 N/mm² foram mais resistentes que as curtidas sem sais de cromo (bioleather (13,11 N/mm; 9,89 N/mm². Peles curtidas por estas técnicas (com cromo e bioleather podem ser utilizadas na confecção de vestuários, pois as médias dos testes de tração, alongamento e rasgamento progressivo foram superiores a 9,80 N/mm², 60% e 14,72 N/mm, respectivamente, valores mínimos recomendados para couros curtidos ao cromo.This research evaluated the effect of different methods (fillet skin removal and tanning methods [with or without chromium salts and bioleather] on leather resistance characteristics of Nile Tilapia (Oreochromis niloticus. Skin from 40 tilapias (450 g were removed: 20 by pliers and 20 by machine. After skin tanning, the samples were removed for resistance tests, which were done, in a climatized environment (23ºC and 50% air relative humidity, with EMIC dynamometer, at removal speed of 100 ± 20 mm/mm. No effect of fillet skin removal method on progressive tearing and strength was observed. The method of skin removal by machine

  15. Celulas solares e sensores de filme fino de silicio depositados sobre substratos flexiveis =

    Science.gov (United States)

    Pinto, Emilio Sergio Marins Vieira

    Celulas solares flexiveis de filmes finos de silicio sao geralmente fabricadas a baixa temperatura sobre substratos de plastico ou a mais elevadas temperaturas sobre folhas de aco. Esta tese reporta o estudo da deposicao de filmes finos sobre diferentes substratos de plastico, transparentes e coloridos, para celulas solares do tipo sobrestrato e substrato, respectivamente. Como objetivo co-lateral, os filmes dopados depositados sobre plastico foram usados como sensores de deformacao, utilizando as suas propriedades piezo-resistivas. Elevadas taxas de deposicao dos filmes de silicio depositados sobre plastico foram obtidas a baixa temperatura do substrato (150ºC) por rf-PECVD. A influencia de diferentes parametros de deposicao sobre as propriedades e taxa de deposicao dos filmes resultantes foram estudados e correlacionados. Celulas solares de filmes finos de silicio amorfo e microcristalino foram desenvolvidas a baixas temperaturas sobre plasticos. Eficiencias de 5 - 6.5% foram alcancadas para as celulas amorfas e 7.5% para as celulas microcristalinas. Efeitos de aprisionamento da luz foram estudados atraves da texturizacao por ablacao laser de substratos de plastico e corrosao umida de TCO sobre plastico. Filmes finos de silicio microcristalino, depositados por HW-CVD, com fator piezoresistivo de -32.2, foram usados para fabricar sensores de deformacao em uma membrana plastica muito fina (15 μm). Estruturas de teste em textil e a miniaturizacao dos sensores piezoresistivos depositados sobre substratos flexiveis de poliimida foram abordados.

  16. Synthesis of Sol-Gel Precursors for Ceramics from Lunar and Martian Soil Simulars

    Science.gov (United States)

    Sibille, L.; Gavira-Gallardo, J. A.; Hourlier-Bahloul, D.

    2004-01-01

    Recent NASA mission plans for the human exploration of our Solar System has set new priorities for research and development of technologies necessary to enable a long-term human presence on the Moon and Mars. The recovery and processing of metals and oxides from mineral sources on other planets is under study to enable use of ceramics, glasses and metals by explorer outposts. We report initial results on the production of sol-gel precursors for ceramic products using mineral resources available in martian or lunar soil. The presence of SO2, TiO2, and Al2O3 in both martian (44 wt.% SiO2, 1 wt.% TiO2, 7 wt.% Al2O3) and lunar (48 wt.% SiO2, 1.5 wt.% TiO2, 16 wt.% Al2O3) soils and the recent developments in chemical processes to solubilize silicates using organic reagents and relatively little energy indicate that such an endeavor is possible. In order to eliminate the risks involved in the use of hydrofluoric acid to dissolve silicates, two distinct chemical routes are investigated to obtain soluble silicon oxide precursors from lunar and martian soil simulars. Clear solutions of sol-gel precursors have been obtained by dissolution of silica from lunar soil similar JSC-1 in basic ethylene glycol (C2H4(OH)2) solutions to form silicon glycolates. Similarly, sol-gel solutions produced from martian soil simulars reveal higher contents of iron oxides. Characterization of the precursor molecules and efforts to further concentrate and hydrolyze the products to obtain gel materials will be presented for evaluation as ceramic precursors.

  17. Synthesis of Sol-Gel Precursors for Ceramics from Lunar and Martian Soil Simulars

    Science.gov (United States)

    Sibille, L.; Gavira-Gallardo, J. A.; Hourlier-Bahloul, D.

    2003-01-01

    Recent NASA mission plans for the human exploration of our Solar System has set new priorities for research and development of technologies necessary to enable a long-term human presence on the Moon and Mars. The recovery and processing of metals and oxides from mineral sources on other planets is under study to enable use of ceramics, glasses and metals by explorer outposts. We report initial results on the production of sol-gel precursors for ceramic products using mineral resources available in martian or lunar soil. The presence of SiO2, TiO2, and Al2O3 in both martian (44 wt.% SiO2, 1 wt.% TiO2,7 wt.% Al2O3) and lunar (48 wt.% SiO2, 1.5 wt.% TiO2, 16 wt.% Al2O3) soils and the recent developments in chemical processes to solubilize silicates using organic reagents and relatively little energy indicate that such an endeavor is possible. In order to eliminate the risks involved in the use of hydrofluoric acid to dissolve silicates, two distinct chemical routes are investigated to obtain soluble silicon oxide precursors from lunar and martian soil simulars. Clear solutions of sol-gel precursors have been obtained by dissolution of silica from lunar soil simular in basic ethylene glycol (C2H4(OH)2) solutions to form silicon glycolates. Similarly, sol-gel solutions produced from martian soil simulars reveal higher contents of iron oxides. The elemental composition and structure of the precursor molecules were characterized. Further concentration and hydrolysis of the products was performed to obtain gel materials for evaluation as ceramic precursors.

  18. Relative importance and interactions of furan precursors in sterilised, vegetable-based food systems.

    Science.gov (United States)

    Palmers, Stijn; Grauwet, Tara; Buvé, Carolien; Vanratingen, Koen; Kebede, Biniam T; Goos, Peter; Hendrickx, Marc E; Van Loey, Ann

    2016-01-01

    Mitigation strategies aimed at an intervention in the reaction pathways for furan formation (e.g., by adjusting precursor concentrations) might offer an additional route for furan reduction in sterilised, vegetable-based foods, without adverse effects on other food safety or quality attributes. As a first step towards product reformulation, the aim of the present study was to determine the relative importance and interactions of possible furan precursors in these types of foods. Based on an I-optimal experimental design, potato purée (naturally low in furan precursors) was spiked with known amounts of sugars, ascorbic acid, olive oil and β-carotene, and subjected to a thermal sterilisation. Significant correlations were observed between furan concentrations after thermal treatment and starting concentrations of ascorbic acid and monosaccharides (i.e., fructose and glucose). Ascorbic acid had a clear furan-reducing effect as an antioxidant by protecting (polyunsaturated) fatty acids against oxidative degradation. Fructose and glucose were the main precursors, which can most probably be attributed to their high, but realistic, concentrations in the product. The contributions of fatty acids and β-carotene were strongly dependent on redox interactions with other food constituents. In the same potato purées, only low concentrations (0-2 ng g(-1) purée) of 2-methylfuran were detected, indicating that the direct importance of the spiked food constituents as a precursor for methylfuran formation was rather small. Based on the results of this study, reducing the amount of monosaccharides or adjusting the redox conditions of the matrix are suggested as two possible approaches for furan mitigation on the product side.

  19. Vanemuislased jagasid oma majja tunnustust

    Index Scriptorium Estoniae

    2010-01-01

    Vanemuise loomenõukogu jagas aastaauhindu. Autospiriti-nimeline draamaauhind läks Maarja Mittile, Torrese-nimelise balletiauhinna sai Colin Thomas Maggs, Kinema-nimelise tehnilise töötaja auhinna sai Jaan Koiduaru, loomenõukogu eripreemia sai trupijuht Eda Hinno ning haldustöötaja müügiassistendi preemia Sanna Pindma. Samuti jagati kolleegipreemiaid

  20. Maadlusfilm tõi Kuldlõvi / Tiit Tuumalu

    Index Scriptorium Estoniae

    Tuumalu, Tiit, 1971-

    2008-01-01

    65. Veneetsia filmifestivali auhinnasaajad. Peauhinna sai Darren Aronofsky "Maadleja" ("The Wrestler"), lavastaja Hõbelõvi sai Aleksei German filmiga "Pabersõdur" ("Bumazhnõi soldat"). Žürii eriauhinna sai Etioopia lavastaja Haile Gerima "Teza", programmi "Horisondid" võitis filipiinlase Lav Diazi "Melanhoolia", lühifilmide osas võitis mehhikase Carlos Armella "Maa ja leib"

  1. Hotspot ignition using a Z-pinch precursor plasma in a magneto-inertial ICF scheme

    International Nuclear Information System (INIS)

    Chittenden, J.P.; Vincent, P.; Jennings, C.A.; Ciardi, A.

    2006-01-01

    Precursor plasma flow is a common feature of wire array Z-pinches. The precursor flow represents a fraction of the mass of the array which arrives on the axis early in time and remains confined at high density by the inertia of further material bombarding the axis. Later on, the main implosion of the Z-pinch then compresses this precursor to substantially higher density. We show that if the same system can be generated with a Deuterium-Tritium plasma then the precursor provides an ideal target for a cylindrical magneto-inertial ICF scheme. The implosion of the DT Z-pinch produces a dense, low temperature shell which compressively heats the precursor target to high temperatures and tamps its expansion. The azimuthal magnetic field in the hotspot is sufficient to reduce the Larmor radius for the alpha particles to much less than the hotspot size, which dramatically reduces the pR required for ignition. A computational analysis of this approach is presented, including a study of the thermonuclear burn wave propagation. The robustness of the scheme with respect to instabilities, confinement time and drive parameters is examined. The results indicate that a high energy gain can be achieved using Z-pinches with 50-100 MA currents and a few hundred nanosecond rise-times. This work was partially supported by the U.S. Department of Energy through cooperative agreement DE-FC03-02NA00057

  2. The influence of precursor addition order on the porosity of sol-gel bioactive glasses.

    Science.gov (United States)

    Fernando, Delihta; Colon, Pierre; Cresswell, Mark; Journet, Catherine; Pradelle-Plasse, Nelly; Jackson, Phil; Grosgogeat, Brigitte; Attik, Nina

    2018-06-16

    The superior textural properties of sol-gel derived bioactive glasses compared to conventional melt quench glasses accounts for their accelerated bioactivity in vitro. Several studies have explored ways to improve the surface properties of sol-gel glasses in order to maximise their efficiency for bone and tooth regeneration. In this study, we investigated the effect of order of network modifying precursor addition on the textural properties of sol-gel derived bioactive glasses. The effect of precursor addition order on the glass characteristics was assessed by switching the order of network modifying precursor (calcium acetate monohydrate and sodium acetate anhydrous) addition for a fixed composition of bioactive glass (75SiO 2 :5CaO:10Na 2 O:10P 2 O 5 ). The results of this study showed that the order of precursor addition does influence the porosity of these glasses. For the glasses of a fixed composition and preparation conditions we achieved a doubling of surface area, a 1.5 times increase in pore volume and a 1.2 times decrease in pore size just by the mixing the network modifying precursors and adding them together in the sol-gel preparation. This simple and straightforward route adaptation to the preparation of bioactive glasses would allow us to enhance the textural properties of existing and novel composition of bioactive glasses and thus accelerate their bioactivity. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

  3. Process for forming seamless tubing of zirconium or titanium alloys from welded precursors

    International Nuclear Information System (INIS)

    Sabol, G.P.; Barry, R.F.

    1987-01-01

    A process is described for forming seamless tubing of a material selected from zirconium, zirconium alloys, titanium, and titanium alloys, from welded precursor tubing of the material, having a heterogeneous structure resulting from the welding thereof. The process consists of: heating successive axial segments of the welded tubing, completely through the wall thereof, including the weld, to uniformly transform the heterogeneous, as welded, material into the beta phase; quenching the beta phase tubing segments, the heating and quenching effected sufficiently rapid enough to produce a fine sized beta grain structure completely throughout the precursor tubing, including the weld, and to prevent growth of beta grains within the material larger than 200 micrometers in diameter; and subsequently uniformly deforming the quenched precursor tubing by cold reduction steps to produce a seamless tubing of final size and shape

  4. CVD of SiC and AlN using cyclic organometallic precursors

    Science.gov (United States)

    Interrante, L. V.; Larkin, D. J.; Amato, C.

    1992-01-01

    The use of cyclic organometallic molecules as single-source MOCVD precursors is illustrated by means of examples taken from our recent work on AlN and SiC deposition, with particular focus on SiC. Molecules containing (AlN)3 and (SiC)2 rings as the 'core structure' were employed as the source materials for these studies. The organoaluminum amide, (Me2AlNH2)3, was used as the AlN source and has been studied in a molecular beam sampling apparatus in order to determine the gas phase species present in a hot-wall CVD reactor environment. In the case of SiC CVD, a series of disilacyclobutanes (Si(XX')CH2)2 (with X and X' = H, CH3, and CH2SiH2CH3), were examined in a cold-wall, hot-stage CVD reactor in order to compare their relative reactivities and prospective utility as single-source CVD precursors. The parent compound, disilacyclobutane, (SiH2CH2)2, was found to exhibit the lowest deposition temperature (ca. 670 C) and to yield the highest purity SiC films. This precursor gave a highly textured, polycrystalline film on the Si(100) substrates.

  5. Meninges harbor cells expressing neural precursor markers during development and adulthood.

    Science.gov (United States)

    Bifari, Francesco; Berton, Valeria; Pino, Annachiara; Kusalo, Marijana; Malpeli, Giorgio; Di Chio, Marzia; Bersan, Emanuela; Amato, Eliana; Scarpa, Aldo; Krampera, Mauro; Fumagalli, Guido; Decimo, Ilaria

    2015-01-01

    Brain and skull developments are tightly synchronized, allowing the cranial bones to dynamically adapt to the brain shape. At the brain-skull interface, meninges produce the trophic signals necessary for normal corticogenesis and bone development. Meninges harbor different cell populations, including cells forming the endosteum of the cranial vault. Recently, we and other groups have described the presence in meninges of a cell population endowed with neural differentiation potential in vitro and, after transplantation, in vivo. However, whether meninges may be a niche for neural progenitor cells during embryonic development and in adulthood remains to be determined. In this work we provide the first description of the distribution of neural precursor markers in rat meninges during development up to adulthood. We conclude that meninges share common properties with the classical neural stem cell niche, as they: (i) are a highly proliferating tissue; (ii) host cells expressing neural precursor markers such as nestin, vimentin, Sox2 and doublecortin; and (iii) are enriched in extracellular matrix components (e.g., fractones) known to bind and concentrate growth factors. This study underlines the importance of meninges as a potential niche for endogenous precursor cells during development and in adulthood.

  6. Non-Viral Generation of Neural Precursor-like Cells from Adult Human Fibroblasts

    Directory of Open Access Journals (Sweden)

    Maucksch C

    2012-01-01

    Full Text Available Recent studies have reported direct reprogramming of human fibroblasts to mature neurons by the introduction of defined neural genes. This technology has potential use in the areas of neurological disease modeling and drug development. However, use of induced neurons for large-scale drug screening and cell-based replacement strategies is limited due to their inability to expand once reprogrammed. We propose it would be more desirable to induce expandable neural precursor cells directly from human fibroblasts. To date several pluripotent and neural transcription factors have been shown to be capable of converting mouse fibroblasts to neural stem/precursor-like cells when delivered by viral vectors. Here we extend these findings and demonstrate that transient ectopic insertion of the transcription factors SOX2 and PAX6 to adult human fibroblasts through use of non-viral plasmid transfection or protein transduction allows the generation of induced neural precursor (iNP colonies expressing a range of neural stem and pro-neural genes. Upon differentiation, iNP cells give rise to neurons exhibiting typical neuronal morphologies and expressing multiple neuronal markers including tyrosine hydroxylase and GAD65/67. Importantly, iNP-derived neurons demonstrate electrophysiological properties of functionally mature neurons with the capacity to generate action potentials. In addition, iNP cells are capable of differentiating into glial fibrillary acidic protein (GFAP-expressing astrocytes. This study represents a novel virus-free approach for direct reprogramming of human fibroblasts to a neural precursor fate.

  7. Surface structural evolvement in the conversion of polyacrylonitrile precursors to carbon fibers

    International Nuclear Information System (INIS)

    Qian, Xin; Zou, Ruifen; OuYang, Qin; Wang, Xuefei; Zhang, Yonggang

    2015-01-01

    Highlights: • The characteristic striated topography of PAN precursors resulted from the wet spinning process could pass down to carbon fibers. • The ridges and grooves monitored became much more well-defined after the thermo-oxidation. • Both the depth and the width of longitudinal grooves decreased after the carbonization. • Carbon, nitrogen, oxygen and silicon were the governing elements on the fiber surface. - Abstract: Surface structural evolvement in the conversion of polyacrylonitrile (PAN) precursors to carbon fibers was investigated through scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). SEM results showed that the characteristic striated topography of PAN precursors resulted from the wet spinning process could pass down to carbon fibers. The fiber diameter gradually decreased from 11.3 μm to 5.5 μm and the corresponding density increased from 1.18 g/cm 3 to 1.80 g/cm 3 in the conversion of PAN precursors to carbon fibers. The ridges and grooves monitored by AFM became much more well-defined after the thermo-oxidation. However, the original longitudinal grooves were destroyed and both the depth and the width of longitudinal grooves decreased after the carbonization. XPS results revealed that carbon, nitrogen, oxygen and silicon were the governing elements on the fiber surface. The −C−C functional groups was the dominant groups and the relative contents of −C=O and −COO groups gradually increased in the process of thermo-oxidation and carbonization

  8. Some peculiarities of zirconium tungstate synthesis by thermal decomposition of hydrothermal precursors

    Energy Technology Data Exchange (ETDEWEB)

    Gubanov, Alexander I., E-mail: gubanov@niic.nsc.su [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Akad. Lavrentiev Prospekt 3, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation); Dedova, Elena S. [Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences, pr. Akademicheskii 2/4, 634021 Tomsk (Russian Federation); Tomsk Polytechnic University, Lenin Avenue 30, 634050 Tomsk (Russian Federation); Plyusnin, Pavel E.; Filatov, Eugeny Y. [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Akad. Lavrentiev Prospekt 3, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation); Kardash, Tatyana Y. [Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Akad. Lavrentiev Prospekt 5, 630090 Novosibirsk (Russian Federation); Korenev, Sergey V. [Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Akad. Lavrentiev Prospekt 3, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, Pirogova str. 2, 630090 Novosibirsk (Russian Federation); Kulkov, Sergey N. [Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences, pr. Akademicheskii 2/4, 634021 Tomsk (Russian Federation); Tomsk Polytechnic University, Lenin Avenue 30, 634050 Tomsk (Russian Federation)

    2014-12-10

    Highlights: • Synthesis of ZrW{sub 2}O{sub 8} using hydrothermal method. • On hydrothermal synthesis optimal conc. of HCl in the reaction mixture is 2.3 M. • Thermal decomposition of ZrW{sub 2}O{sub 7}((OH){sub 1.5},Cl{sub 0.5})·2H{sub 2}O begins are 200 °S. • Amorphous intermediate crystallizes into cubic single-phase ZrW{sub 2}O{sub 8} above 550 °S. • ZrW{sub 2}O{sub 8} destructed at temperatures above 700 °S. - Abstract: This article discusses some peculiarities of the synthesis of ZrW{sub 2}O{sub 8} (1) using thermal decomposition of the precursor ZrW{sub 2}O{sub 7}((OH){sub 1.5},Cl{sub 0.5})·2H{sub 2}O (2) prepared by hydrothermal method. On hydrothermal synthesis of 2 the optimal concentration of hydrochloric acid in the reaction mixture is about 2.3 M. TG approach to determine the chemical composition of the precursor was suggested. It has been found that the precursor for the synthesis of zirconium tungstate has chemical formula 2. Thermal decomposition of the precursor 2 begins at 200 °S and affords an amorphous intermediate, which crystallizes as a cubic phase 1 above 550 °S with an exoeffect. The temperature of the beginning of the transition from amorphous to the crystalline state is 350 ± 25 °S.

  9. Formation, precursors, control, and occurrence of nitrosamines in drinking water: a review.

    Science.gov (United States)

    Krasner, Stuart W; Mitch, William A; McCurry, Daniel L; Hanigan, David; Westerhoff, Paul

    2013-09-01

    This review summarizes major findings over the last decade related to nitrosamines in drinking water, with a particular focus on N-nitrosodimethylamine (NDMA), because it is among the most widely detected nitrosamines in drinking waters. The reaction of inorganic dichloramine with amine precursors is likely the dominant mechanism responsible for NDMA formation in drinking waters. Even when occurrence surveys found NDMA formation in chlorinated drinking waters, it is unclear whether chloramination resulted from ammonia in the source waters. NDMA formation has been associated with the use of quaternary amine-based coagulants and anion exchange resins, and wastewater-impaired source waters. Specific NDMA precursors in wastewater-impacted source waters may include tertiary amine-containing pharmaceuticals or other quaternary amine-containing constituents of personal care products. Options for nitrosamine control include physical removal of precursors by activated carbon or precursor deactivation by application of oxidants, particularly ozone or chlorine, upstream of chloramination. Although NDMA has been the most prevalent nitrosamine detected in worldwide occurrence surveys, it may account for only ≈ 5% of all nitrosamines in chloraminated drinking waters. Other significant contributors to total nitrosamines are poorly characterized. However, high levels of certain low molecular weight nitrosamines have been detected in certain Chinese waters suspected to be impaired by industrial effluents. The review concludes by identifying research needs that should be addressed over the next decade. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Evaluation of operating experience: The precursor study (GPS) performed in the Federal Republic of Germany. Working material

    International Nuclear Information System (INIS)

    1991-01-01

    Probabilistic Safety Assessments (PSAs) are systematic and quantitative predictions of possible accident scenarios at technical installations on the basis of data gained from the past experience on similar technical installations. For supporting PSAs by operational experience as far as possible Precursor studies are performed. An Accident Sequence Precursor is defined as an observed event which could results, in coincidence with additional postulated events, in a potential severe core damage accident. In the presented case study the procedure of such Precursor studies is explained. Particularly, the methodology and the results of the plant-specific Precursor (GPS) performed in the Federal Republic of Germany are shown in detail. 26 refs, 13 figs, 8 tabs

  11. Evaluation of operating experience: The precursor study (GPS) performed in the Federal Republic of Germany. Working material

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-31

    Probabilistic Safety Assessments (PSAs) are systematic and quantitative predictions of possible accident scenarios at technical installations on the basis of data gained from the past experience on similar technical installations. For supporting PSAs by operational experience as far as possible Precursor studies are performed. An Accident Sequence Precursor is defined as an observed event which could results, in coincidence with additional postulated events, in a potential severe core damage accident. In the presented case study the procedure of such Precursor studies is explained. Particularly, the methodology and the results of the plant-specific Precursor (GPS) performed in the Federal Republic of Germany are shown in detail. 26 refs, 13 figs, 8 tabs.

  12. Impuesto sobre las transacciones financieras: Justicia fiscal

    OpenAIRE

    Mariño, José Ramón

    2016-01-01

    7 p.[Variante del título de la publicación : Boletín electrónico de Hegoa] [ESP] El Impuesto sobre las transacciones financieras se basa en establecer un gravamen sobre las operaciones financieras con el fin de estabilizar los mercados como consecuencia de la disminución de la especulación a corto plazo. Además es una fuente de financiación de inversiones socialmente deseables. Diez países de la Unión Europea han expresado su deseo de introducir el ITF, sin emba...

  13. Naturally death-resistant precursor cells revealed as the origin of retinoblastoma

    DEFF Research Database (Denmark)

    Trinh, Emmanuelle; Lazzerini Denchi, Eros; Helin, Kristian

    2004-01-01

    The molecular mechanisms and the cell-of-origin leading to retinoblastoma are not well defined. In this issue of Cancer Cell, Bremner and colleagues describe the first inheritable model of retinoblastoma, revealing that loss of the pocket proteins pRb and p107 deregulates cell cycle exit in retinal...... precursors. The authors show that a subset of these precursors contain an inherent resistance to apoptosis, and that while most terminally differentiate, some are likely to acquire additional mutations, leading to tumor formation. Thus, this work defines the cell-of-origin of retinoblastoma and suggests...... that mutations giving increased proliferative capacity are required for retinoblastoma development....

  14. The immediate nucleotide precursor, guanosine triphosphate, in the riboflavin biosynthetic pathway

    International Nuclear Information System (INIS)

    Mitsuda, Hisateru; Nakajima, Kenji; Nadamoto, Tomonori

    1977-01-01

    In the present paper, the nucleotide precursor of riboflavin was investigated by experiments with labeled purines using non-growing cells of Eremothecium ashbyii. The added purines, at 10 -4 M, were effectively incorporated into riboflavin at an early stage of riboflavin biosynthesis under the experimental conditions. In particular, both labeled xanthine and labeled guanine were specifically transported to guanosine nucleotides, GMP, GDP, GDP-Mannose and GTP, in the course of the riboflavin biosynthesis. A comparison of specific activities of labeled guanosine nucleotides and labeled riboflavin indicated that the nucleotide precursor of riboflavin is guanosine triphosphate. From the results obtained, a biosynthetic pathway of riboflavin is proposed. (auth.)

  15. Stand-level variation in evapotranspiration in non-water-limited eucalypt forests

    Science.gov (United States)

    Benyon, Richard G.; Nolan, Rachael H.; Hawthorn, Sandra N. D.; Lane, Patrick N. J.

    2017-08-01

    To better understand water and energy cycles in forests over years to decades, measurements of spatial and long-term temporal variability in evapotranspiration (Ea) are needed. In mountainous terrain, plot-level measurements are important to achieving this. Forest inventory data including tree density and size measurements, often collected repeatedly over decades, sample the variability occurring within the geographic and topographic range of specific forest types. Using simple allometric relationships, tree stocking and size data can be used to estimate variables including sapwood area index (SAI), which may be strongly correlated with annual Ea. This study analysed plot-level variability in SAI and its relationship with overstorey and understorey transpiration, interception and evaporation over a 670 m elevation gradient, in non-water-limited, even-aged stands of Eucalyptus regnans F. Muell. to determine how well spatial variation in annual Ea from forests can be mapped using SAI. Over the 3 year study, mean sap velocity in five E. regnans stands was uncorrelated with overstorey sapwood area index (SAI) or elevation: annual transpiration was predicted well by SAI (R2 0.98). Overstorey and total annual interception were positively correlated with SAI (R2 0.90 and 0.75). Ea from the understorey was strongly correlated with vapour pressure deficit (VPD) and net radiation (Rn) measured just above the understorey, but relationships between understorey Ea and VPD and Rn differed between understorey types and understorey annual Ea was not correlated with SAI. Annual total Ea was also strongly correlated with SAI: the relationship being similar to two previous studies in the same region, despite differences in stand age and species. Thus, spatial variation in annual Ea can be reliably mapped using measurements of SAI.

  16. Notas sobre Matisia longiflora Gleas. (Bombacaceae Notas sobre Matisia longiflora Gleas. (Bombacaceae

    Directory of Open Access Journals (Sweden)

    Fernández Alonso José Luis

    1992-09-01

    Full Text Available Dentro del grupo de géneros de bombacáceas de hojas simples que componen la tribu Quararibeae (= Matisieae Hutchinson, es Matisia Humb. & Bonpl. el que cuenta con mayor número de especies en Colombia. Al respecto se presentaron recientemente algunas consideraciones preliminares sobre la diversidad de especies en este grupo en Colombia (Fernández Alonso, 1991.

  17. Selective Disparity of Ordinary Chondritic Precursors in Micrometeorite Flux

    Science.gov (United States)

    Rudraswami, N. G.; Fernandes, D.; Naik, A. K.; Shyam Prasad, M.; Carrillo-Sánchez, J. D.; Plane, J. M. C.; Feng, W.; Taylor, S.

    2018-01-01

    All known extraterrestrial dust (micrometeoroids) entering the Earth’s atmosphere is anticipated to have a significant contribution from ordinary chondritic precursors, as seen in meteorites, but this is an apparent contradiction that needs to be addressed. Ordinary chondrites represent a minor contribution to the overall meteor influx compared to carbonaceous chondrites, which are largely dominated by CI and/or CM chondrites. However, the near-Earth asteroid population presents a scenario with sufficient scope for generation of dust-sized debris from ordinary chondritic sources. The bulk chemical composition of 3255 micrometeorites (MMs) collected from Antarctica and deep-sea sediments has shown Mg/Si largely dominated by carbonaceous chondrites, and less than 10% having ordinary chondritic precursors. The chemical ablation model is combined with different initial chondritic compositions (CI, CV, L, LL, H), and the results clearly indicate that high-density (≥2.8 g cm‑3) precursors, such as CV and ordinary chondrites in the size range 100–700 μm and zenith angle 0°–70°, ablate at much faster rates and lose their identity even before reaching the Earth’s surface and hence are under-represented in our collections. Moreover, their ability to survive as MMs remains grim for high-velocity micrometeoroids (>16 km s‑1). The elemental ratio for CV and ordinary chondrites are also similar to each other irrespective of the difference in the initial chemical composition. In conclusion, MMs belonging to ordinary chondritic precursors’ concentrations may not be insignificant in thermosphere, as they are found on Earth’s surface.

  18. Thermal decomposition and spectroscopic investigation of a new aqueous glycolato(-peroxo) Ti(IV) solution-gel precursor

    Energy Technology Data Exchange (ETDEWEB)

    De Dobbelaere, Christopher, E-mail: christopher.dedobbelaere@uhasselt.be [Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Agoralaan Building D, B-3590 Diepenbeek (Belgium); Mullens, Jules, E-mail: jules.mullens@uhasselt.be [Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Agoralaan Building D, B-3590 Diepenbeek (Belgium); Hardy, An, E-mail: an.hardy@uhasselt.be [Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Agoralaan Building D, B-3590 Diepenbeek (Belgium); IMEC vzw, Division IMOMEC, Agoralaan Building D, B-3590 Diepenbeek (Belgium); Van Bael, Marlies K., E-mail: marlies.vanbael@uhasselt.be [Hasselt University, Institute for Materials Research, Inorganic and Physical Chemistry, Agoralaan Building D, B-3590 Diepenbeek (Belgium); IMEC vzw, Division IMOMEC, Agoralaan Building D, B-3590 Diepenbeek (Belgium)

    2011-06-10

    Highlights: {yields} A totally water based glycolato-Ti(IV) precursor is presented and characterized. {yields} The precursors' thermal decomposition profile depends on the ligand to metal ratio. {yields} Titanium is coordinated in an unidentate fashion by the glycolate anion. {yields} Smooth and uniform TiO{sub 2} films can be prepared from the precursor solution. - Abstract: A new aqueous solution-gel precursor based on water soluble glycolato(-peroxo)-Ti(IV) complexes is developed for the preparation of TiO{sub 2} films. With regard to the decomposition of complexes towards oxide formation, it is important to gain insight in the chemical transformations inside the precursor during thermal treatment. Therefore, the thermo-oxidative decomposition pathway of a gel obtained by slow evaporation of the precursor solution is described based on hyphenated thermogravimetric analysis with Fourier transform infrared spectroscopy (TGA-FTIR) and mass spectrometry (TGA-MS). Pure glycolic acid is used as a reference system for this study. By varying the molar glycolic acid to Ti(IV) ratio, the thermal decomposition of the gel can be drastically shortened and the profile's course changed. Gel structure and chemical changes in the gel upon heating are also studied by means of off-line FTIR. A unidentate coordination of the titanium(IV) ion by the carboxylate group of the glycolato ligands and the involvement of the hydroxyl group is confirmed. Phase formation at certain points in the thermal decomposition is studied by X-ray diffraction and Raman spectroscopy. Finally, it is proven that the new precursor is a valuable candidate for the deposition of low carbon containing solution-gel films which can ultimately be converted into smooth and uniform TiO{sub 2} films.

  19. Effect of precursors on flavonoid production by Hydrocotyle ...

    African Journals Online (AJOL)

    Callus tissue of Hydrocotyle bonariensis was initiated from the leaf of H. bonariensis treated with 2 mg/l of 2,4-dichlorophenoxyacetic acid (2,4-D) and 1 mg/l kinetin. The culture was kept at 25°C, under light (cool white fluorescent tubes, 1200 lux). To optimize the precursors to increase the production of flavonoid, different ...

  20. The effect of precursor powder size on the microstructure and integranular properties of Bi2223 superconductors

    Directory of Open Access Journals (Sweden)

    I. Abdolhosseini

    2006-09-01

    Full Text Available  We have studied the effect of precursor powder size on the microstructure and intergranular behavior of polycrystalline Bi2223 superconductors using the XRD, SEM, electrical resistivity and AC susceptibility techniques. Polycrystalline Bi2223 superconductors were prepared from the powders with different milling times. The XRD results show that by decreasing the precursor powder size the Bi2223 phase fraction increases. It was found that the grain size and grain connectivity improved by decreasing the precursor powder size. Analysis of the temperature dependence of the AC susceptibility near the transition temperature (Tc has been done employing Beans critical state model. The observed variation of intergranular critical current densities (Jc with temperature indicates that the decreasing of precursor powder size in the Bi2223 system cases an increase in the intergranular critical current density.

  1. High regioselective acetylation of vitamin A precursors using lipase ...

    African Journals Online (AJOL)

    Administrator

    2011-09-26

    Sep 26, 2011 ... High regioselective acetylation of vitamin A precursors using lipase B from Candida antarctica in organic media. Jingpeng Sun, Keju Jing* and Yinghua Lu. Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen. University, Xiamen 361005, P. R. ...

  2. Carbon molecular sieve membranes prepared from porous fiber precursor

    NARCIS (Netherlands)

    Barsema, J.N.; van der Vegt, N.F.A.; Koops, G.H.; Wessling, Matthias

    2002-01-01

    Carbon molecular sieve (CMS) membranes are usually prepared from dense polymeric precursors that already show intrinsic gas separation properties. The rationale behind this approach is that the occurrence of any kind of initial porosity will deteriorate the final CMS performance. We will show that

  3. Progressing from Identification and Functional Analysis of Precursor Behavior to Treatment of Self-Injurious Behavior

    Science.gov (United States)

    Dracobly, Joseph D.; Smith, Richard G.

    2012-01-01

    This multiple-study experiment evaluated the utility of assessing and treating severe self-injurious behavior (SIB) based on the outcomes of a functional analysis of precursor behavior. In Study 1, a precursor to SIB was identified using descriptive assessment and conditional probability analyses. In Study 2, a functional analysis of precursor…

  4. The wireless networking system of Earthquake precursor mobile field observation

    Science.gov (United States)

    Wang, C.; Teng, Y.; Wang, X.; Fan, X.; Wang, X.

    2012-12-01

    The mobile field observation network could be real-time, reliably record and transmit large amounts of data, strengthen the physical signal observations in specific regions and specific period, it can improve the monitoring capacity and abnormal tracking capability. According to the features of scatter everywhere, a large number of current earthquake precursor observation measuring points, networking technology is based on wireless broadband accessing McWILL system, the communication system of earthquake precursor mobile field observation would real-time, reliably transmit large amounts of data to the monitoring center from measuring points through the connection about equipment and wireless accessing system, broadband wireless access system and precursor mobile observation management center system, thereby implementing remote instrument monitoring and data transmition. At present, the earthquake precursor field mobile observation network technology has been applied to fluxgate magnetometer array geomagnetic observations of Tianzhu, Xichang,and Xinjiang, it can be real-time monitoring the working status of the observational instruments of large area laid after the last two or three years, large scale field operation. Therefore, it can get geomagnetic field data of the local refinement regions and provide high-quality observational data for impending earthquake tracking forecast. Although, wireless networking technology is very suitable for mobile field observation with the features of simple, flexible networking etc, it also has the phenomenon of packet loss etc when transmitting a large number of observational data due to the wireless relatively weak signal and narrow bandwidth. In view of high sampling rate instruments, this project uses data compression and effectively solves the problem of data transmission packet loss; Control commands, status data and observational data transmission use different priorities and means, which control the packet loss rate within

  5. Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.L.

    1979-01-01

    The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

  6. Effect of precursor concentration and spray pyrolysis temperature upon hydroxyapatite particle size and density.

    Science.gov (United States)

    Cho, Jung Sang; Lee, Jeong-Cheol; Rhee, Sang-Hoon

    2016-02-01

    In the synthesis of hydroxyapatite powders by spray pyrolysis, control of the particle size was investigated by varying the initial concentration of the precursor solution and the pyrolysis temperature. Calcium phosphate solutions (Ca/P ratio of 1.67) with a range of concentrations from 0.1 to 2.0 mol/L were prepared by dissolving calcium nitrate tetrahydrate and diammonium hydrogen phosphate in deionized water and subsequently adding nitric acid. Hydroxyapatite powders were then synthesized by spray pyrolysis at 900°C and at 1500°C, using these calcium phosphate precursor solutions, under the fixed carrier gas flow rate of 10 L/min. The particle size decreased as the precursor concentration decreased and the spray pyrolysis temperature increased. Sinterability tests conducted at 1100°C for 1 h showed that the smaller and denser the particles were, the higher the relative densities were of sintered hydroxyapatite disks formed from these particles. The practical implication of these results is that highly sinterable small and dense hydroxyapatite particles can be synthesized by means of spray pyrolysis using a low-concentration precursor solution and a high pyrolysis temperature under a fixed carrier gas flow rate. © 2015 Wiley Periodicals, Inc.

  7. Islandil peeti filmipidu Kuldse Lunni säras / Annika Koppel

    Index Scriptorium Estoniae

    Koppel, Annika

    2007-01-01

    Muljeid Islandilt, Reykjaviki 4. rahvusvaheliselt filmifestivalilt, mis toimus 27. septembrist 7. oktoobrini s.a. Peauhinna sai ungarlase Csaba Bolloki "Iska reis" ("Iszka utazasa"). Publiku auhinna sai Anton Corbijni "Kontroll", FIPRESCI auhinna sai taanlase Peter Schınau Fogi "Nutmise kunst". Ka iraanlase Fazli Bayrami filmist "Kas sul on veel õuna?" ja argentiinlanna Lucia Puenzo filmist "XXY"

  8. H and C NMR investigations of Pb(Zr,Ti)O3 thin-film precursor solutions

    International Nuclear Information System (INIS)

    Assink, R.A.; Schwartz, R.W.

    1993-01-01

    Solvent reactions, ligand substitutions, and the oligomer/polymer backbone structure are important factors in the solution preparation of ceramic films. In this study the authors have used H and C NMR spectroscopy to characterize solvent and ligand effects in precursor solutions used for the deposition of ferroelectric PZT (lead zirconate titanate) thin films. Solutions were prepared by a sequential precursor addition method from carboxylate and alkoxide precursors of the three cations, and the solvent, acetic acid, methanol, and water. The results indicate that acetic acid was a key component in the solution preparation process. As observed previously for single metallic component systems, its presence resulted in esterification reactions, leading in the present case to the formation of methyl, isopropyl, and n-butyl acetates. Second, acetic acid functioned as a chemical modifier, or chelating agent, replacing essentially all of the alkoxy ligands of the original precursors. Since alkoxy replacement appeared to be complete, we may describe the PZT species formed in solution as oxo acetate in nature. Finally, the solvent and ligand behavior of a solution prepared by an inverted mixing order was compared to the behavior of the solution prepared by a sequential precursor addition. The spectra for the two solutions were similar, and only differences in the relative intensities of the ester and alcoholic resonances were observed. 29 refs., 5 figs., 3 tabs

  9. Spray drying of silica microparticles for sustained release application with a new sol-gel precursor.

    Science.gov (United States)

    Wang, Bifeng; Friess, Wolfgang

    2017-10-30

    A new precursor, tetrakis(2-methoxyethyl) orthosilicate (TMEOS) was used to fabricate microparticles for sustained release application, specifically for biopharmaceuticals, by spray drying. The advantages of TMEOS over the currently applied precursors are its water solubility and hydrolysis at moderate pH without the need of organic solvents or catalyzers. Thus a detrimental effect on biomolecular drug is avoided. By generating spray-dried silica particles encapsulating the high molecular weight model compound FITC-dextran 150 via the nano spray dryer Büchi-90, we demonstrated how formulation parameters affect and enable control of drug release properties. The implemented strategies to regulate release included incorporating different quantities of dextrans with varying molecular weight as well as adjusting the pH of the precursor solution to modify the internal microstructures. The addition of dextran significantly altered the released amount, while the release became faster with increasing dextran molecular weight. A sustained release over 35days could be achieved with addition of 60 kD dextran. The rate of FITC-Dextran 150 release from the dextran 60 containing particles decreased with higher precursor solution pH. In conclusion, the new precursor TMEOS presents a promising alternative sol-gel technology based carrier material for sustained release application of high molecular weight biopharmaceutical drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. In vitro method determing sensitivity of anticancer agents by incorporation of radioactive precursors

    International Nuclear Information System (INIS)

    Sakakibara, Satoshi

    1983-01-01

    A new sensitivity test of anticancer agents was developed to measure the lethal effects of cancer cells by the incorporation of radioactive precursors. The thousand cancer cells were cultured in a microplate in the presence of anticancer agents. These cells were exposed to radioactive precursors. Two or three days later, the cancer cells were harvested on a glass fiver filter by a multiple automatic cell-harvester and the incorporation of precursors was counted by a liquid scintillation counter. In this study, the in vivo results of drug testing in animal model systems were compared with drug sensitivities. Mice inoculated Ehrlich ascites cells were treated with various kinds of anticancer drugs. The development of the cells was compatible with the result of the sensitivity test. The growths of Lauson and ME-180 cells derived from human cancers implanted subcutaneously to nude mice were also well correlated with this sensitivity test. (author)

  11. Bleogens: Cactus-Derived Anti-Candida Cysteine-Rich Peptides with Three Different Precursor Arrangements

    Directory of Open Access Journals (Sweden)

    Shining Loo

    2017-12-01

    Full Text Available Cysteine-rich peptides (CRPs play important host-defense roles in plants. However, information concerning CRPs in the Cactaceae (cactus family is limited, with only a single cactus-derived CRP described to date. Here, we report the identification of 15 novel CRPs with three different precursor architectures, bleogens pB1-15 from Pereskia bleo of the Cactaceae family. By combining proteomic and transcriptomic methods, we showed that the prototype, bleogen pB1, contained 36 amino acid residues, a six-cysteine motif typical of the six-cysteine-hevein-like peptide (6C-HLP family, and a type I two-domain precursor consisting of an endoplasmic reticulum (ER and a mature domain. In contrast, the precursors of the other 14 bleogens contained a type II three-domain architecture with a propeptide domain inserted between the ER and the mature bleogen domain. Four of these 14 bleogens display a third type of architecture with a tandemly repeating bleogen domain. A search of the Onekp database revealed that <1% plant species possess three different precursor architectures for the biosynthesis of 6C-HLPs, including Lophophora williamsii, Pereskia aculeate, Portulaca cryptopetala, Portulaca oleracea, Portulaca suffruticosa, and Talinum sp. NMR analysis confirmed that bleogen pB1 has cystine-knot disulfide connectivity as well as a two-beta-sheet and a four-loop structural fold that is similar to other 6C-HLPs. Sequence analysis, structural studies, and in silico modeling revealed that bleogen pB1 has a cation-polar-cation motif, a signature heparin-binding motif that was confirmed by heparin affinity chromatography. Cell-based assays showed that bleogen pB1 is non-toxic to mammalian cells but functions as an anti-Candida peptide. Taken together, our findings provide insight into the occurrence, functions and precursor architectures of CRPs in the cactus family.

  12. Long-term culture and differentiation of CNS precursors derived from anterior human neural rosettes following exposure to ventralizing factors

    International Nuclear Information System (INIS)

    Colleoni, Silvia; Galli, Cesare; Giannelli, Serena G.; Armentero, Marie-Therese; Blandini, Fabio; Broccoli, Vania; Lazzari, Giovanna

    2010-01-01

    In this study we demonstrated that neural rosettes derived from human ES cells can give rise either to neural crest precursors, following expansion in presence of bFGF and EGF, or to dopaminergic precursors after exposure to ventralizing factors Shh and FGF8. Both regionalised precursors are capable of extensive proliferation and differentiation towards the corresponding terminally differentiated cell types. In particular, peripheral neurons, cartilage, bone, smooth muscle cells and also pigmented cells were obtained from neural crest precursors while tyrosine hydroxylase and Nurr1 positive dopaminergic neurons were derived from FGF8 and Shh primed rosette cells. Gene expression and immunocytochemistry analyses confirmed the expression of dorsal and neural crest genes such as Sox10, Slug, p75, FoxD3, Pax7 in neural precursors from bFGF-EGF exposed rosettes. By contrast, priming of rosettes with FGF8 and Shh induced the expression of dopaminergic markers Engrailed1, Pax2, Pitx3, floor plate marker FoxA2 and radial glia markers Blbp and Glast, the latter in agreement with the origin of dopaminergic precursors from floor plate radial glia. Moreover, in vivo transplant of proliferating Shh/FGF8 primed precursors in parkinsonian rats demonstrated engraftment and terminal dopaminergic differentiation. In conclusion, we demonstrated the derivation of long-term self-renewing precursors of selected regional identity as potential cell reservoirs for cell therapy applications, such as CNS degenerative diseases, or for the development of toxicological tests.

  13. Long-term culture and differentiation of CNS precursors derived from anterior human neural rosettes following exposure to ventralizing factors

    Energy Technology Data Exchange (ETDEWEB)

    Colleoni, Silvia, E-mail: silviacolleoni@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Galli, Cesare [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy); Dipartimento Clinico Veterinario, Universita di Bologna, Via Tolara di Sopra 50, 40064 Ozzano Emilia (Italy); Giannelli, Serena G. [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Armentero, Marie-Therese; Blandini, Fabio [Laboratory of Functional Neurochemistry, Interdepartmental Research Center for Parkinson' s Disease, Neurological Institute C. Mondino, Via Mondino 2, 27100 Pavia (Italy); Broccoli, Vania, E-mail: broccoli.vania@hsr.it [Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Via Olgettina 58, 20132 Milan (Italy); Lazzari, Giovanna, E-mail: giovannalazzari@avantea.it [Laboratorio di Tecnologie della Riproduzione, Avantea, Via Porcellasco 7/f, 26100 Cremona (Italy)

    2010-04-15

    In this study we demonstrated that neural rosettes derived from human ES cells can give rise either to neural crest precursors, following expansion in presence of bFGF and EGF, or to dopaminergic precursors after exposure to ventralizing factors Shh and FGF8. Both regionalised precursors are capable of extensive proliferation and differentiation towards the corresponding terminally differentiated cell types. In particular, peripheral neurons, cartilage, bone, smooth muscle cells and also pigmented cells were obtained from neural crest precursors while tyrosine hydroxylase and Nurr1 positive dopaminergic neurons were derived from FGF8 and Shh primed rosette cells. Gene expression and immunocytochemistry analyses confirmed the expression of dorsal and neural crest genes such as Sox10, Slug, p75, FoxD3, Pax7 in neural precursors from bFGF-EGF exposed rosettes. By contrast, priming of rosettes with FGF8 and Shh induced the expression of dopaminergic markers Engrailed1, Pax2, Pitx3, floor plate marker FoxA2 and radial glia markers Blbp and Glast, the latter in agreement with the origin of dopaminergic precursors from floor plate radial glia. Moreover, in vivo transplant of proliferating Shh/FGF8 primed precursors in parkinsonian rats demonstrated engraftment and terminal dopaminergic differentiation. In conclusion, we demonstrated the derivation of long-term self-renewing precursors of selected regional identity as potential cell reservoirs for cell therapy applications, such as CNS degenerative diseases, or for the development of toxicological tests.

  14. Major Accidents (Gray Swans) Likelihood Modeling Using Accident Precursors and Approximate Reasoning.

    Science.gov (United States)

    Khakzad, Nima; Khan, Faisal; Amyotte, Paul

    2015-07-01

    Compared to the remarkable progress in risk analysis of normal accidents, the risk analysis of major accidents has not been so well-established, partly due to the complexity of such accidents and partly due to low probabilities involved. The issue of low probabilities normally arises from the scarcity of major accidents' relevant data since such accidents are few and far between. In this work, knowing that major accidents are frequently preceded by accident precursors, a novel precursor-based methodology has been developed for likelihood modeling of major accidents in critical infrastructures based on a unique combination of accident precursor data, information theory, and approximate reasoning. For this purpose, we have introduced an innovative application of information analysis to identify the most informative near accident of a major accident. The observed data of the near accident were then used to establish predictive scenarios to foresee the occurrence of the major accident. We verified the methodology using offshore blowouts in the Gulf of Mexico, and then demonstrated its application to dam breaches in the United Sates. © 2015 Society for Risk Analysis.

  15. The role of reduced aerosol precursor emissions in driving near-term warming

    International Nuclear Information System (INIS)

    Gillett, Nathan P; Von Salzen, Knut

    2013-01-01

    The representative concentration pathway (RCP) scenarios all assume stringent emissions controls on aerosols and their precursors, and hence include progressive decreases in aerosol and aerosol precursor emissions through the 21st century. Recent studies have suggested that the resultant decrease in aerosols could drive rapid near-term warming, which could dominate the effects of greenhouse gas (GHG) increases in the coming decades. In CanESM2 simulations, we find that under the RCP 2.6 scenario, which includes the fastest decrease in aerosol and aerosol precursor emissions, the contribution of aerosol reductions to warming between 2000 and 2040 is around 30%. Moreover, the rate of warming in the RCP 2.6 simulations declines gradually from its present-day value as GHG emissions decrease. Thus, while aerosol emission reductions contribute to gradual warming through the 21st century, we find no evidence that aerosol emission reductions drive particularly rapid near-term warming in this scenario. In the near-term, as in the long-term, GHG increases are the dominant driver of warming. (letter)

  16. Er:YAB nanoparticles and vitreous thin films by the polymeric precursor method

    Energy Technology Data Exchange (ETDEWEB)

    Maia, Lauro J. Q., E-mail: lauro@if.sc.usp.b [Universidade de Sao Paulo, Grupo Crescimento de Cristais e Materiais Ceramicos, Departamento de Fisica e Ciencia dos Materiais, Instituto de Fisica de Sao Carlos (Brazil); Ibanez, Alain; Ortega, Luc [Laboratoire de Cristallographie CNRS associe a l' Universite Joseph Fourier et a l' INPG (France); Mastelaro, Valmor R.; Hernandes, Antonio C. [Universidade de Sao Paulo, Grupo Crescimento de Cristais e Materiais Ceramicos, Departamento de Fisica e Ciencia dos Materiais, Instituto de Fisica de Sao Carlos (Brazil)

    2008-12-15

    The synthesis of Y{sub 0.9}Er{sub 0.1}Al{sub 3}(BO{sub 3}){sub 4} crystalline powders and vitreous thin films were studied. Precursor solutions were obtained using a modified polymeric precursor method using d-sorbitol as complexant agent. The chemical reactions were described. Y{sub 0.9}Er{sub 0.1}Al{sub 3}(BO{sub 3}){sub 4} composition presents good thermal stability with regard to crystallization. The Y{sub 0.9}Er{sub 0.1}Al{sub 3}(BO{sub 3}){sub 4} crystallized phase can be obtained at 1,150 {sup o}C, in agreement with other authors. Crack- and porosity-free films were obtained with very small grain size and low RMS roughness. The films thickness revealed to be linearly dependent on precursor solution viscosity, being the value of 25 mPa s useful to prepare high-quality amorphous multi-layers (up to {approx} 800 nm) at 740 {sup o}C during 2 h onto silica substrates by spin coating with a gyrset technology.

  17. Synthesis and optical properties of Mg-Al layered double hydroxides precursor powders

    Directory of Open Access Journals (Sweden)

    Chia-Hsuan Lin

    2017-12-01

    Full Text Available The synthesis and optical properties of Mg-Al layered double hydroxide (LDH precursor powders were investigated using X-ray diffraction (XRD, Fourier transform-infrared (FT-IR spectroscopy, transmission electron microscopy (TEM, selected area electron diffraction (SAED, high-resolution TEM (HRTEM, UV-transmission spectrometer, and fluorescence spectrophotometer. The FT-IR results show that the intense absorption at around 1363–1377 cm-1 can be assigned to the antisymmetric ν3 mode of interlayer carbonate anions because the LDH phase contains some CO32-. The XRD results show that all of the Mg-Al LDH precursor powders contain only a single phase of [Mg0.833Al0.167(OH2](CO30.083·(H2O0.75 but have broad and weak intensities of peaks. All of Mg-Al LDHs precursor powders before calcination have the same photoluminescence (PL spectra. Moreover, these spectra were excited at λex = 235 nm, and the broad emission band was in the range 325-650 nm. In the range, there were relatively strong intensity at around 360, 407 and 510 nm, respectively.

  18. Human haemato-endothelial precursors: cord blood CD34+ cells produce haemogenic endothelium.

    Directory of Open Access Journals (Sweden)

    Elvira Pelosi

    Full Text Available Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-, triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45- capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level.

  19. Influência de sais e do pH da água na eficiência de imazethapyr + imazapic no controle de arroz-vermelho Influence of salts and water pH on the efficiency of imazethapyr + imazapic for red rice control

    Directory of Open Access Journals (Sweden)

    D.M. Sanchotene

    2007-01-01

    Full Text Available Na safra agrícola de 2004/2005, em Santa Maria/RS, foi realizado um experimento com o objetivo de avaliar a influência de sais e do pH da água de diferentes fontes de abastecimento de pulverizadores (água de fonte mineral, água de açude e água de poço artesiano sobre a eficiência de imazethapyr (75 g L-1 + imazapic (25 g L-1 no controle de arroz-vermelho (Oryza sativa. No preparo da calda para pulverização do herbicida, foi utilizada água na sua condição original e água acidificada com ácido cítrico até pH 4,5. Foi verificado que os tratamentos com água de pH 4,5 proporcionaram maior eficiência da mistura (imazethapyr + imazapic no controle do arroz-vermelho do que com águas alcalinas (pH 9,4 e 8,7. Todos os tratamentos herbicidas causaram intoxicação às plantas do arroz cultivado. Entretanto, nos tratamentos em que se utilizou água alcalina, foi observada recuperação mais rápida das plantas de arroz, cultivar IRGA 422 CL.This research was carried out in Santa Maria/RS during the 2004/2005 crop season to evaluate the influence of salts and water pH on different sources of spray suppliers (mineral water, dam water and artesian well water on imazethapyr (75 g L-1 + imazapic (25 g L-1 efficiency in red rice control. Thus, water under original condition and acidified water with citric acid to pH 4,5 have been used to prepare the herbicide solutions. It has been verified that the treated plots with water at pH 4,5 showed better action of imazethapyr (75 g L-1 + imazapic (25 g L-1 in the red rice control than alkaline water with pH 9,4 and 8,7. All the treatments with herbicide presented intoxication in the rice. Nevertheless, the treatments with alkaline water showed a fast recuperation in rice plants (IRGA 422CL.

  20. Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder

    Science.gov (United States)

    2017-12-01

    children -autism- spectrum-disorder C. Technologies or techniques Nothing to Report D. Inventions, patent applications, and/or licenses Nothing to Report...AWARD NUMBER: W81XWH-14-1-0526 TITLE: Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder...TITLE AND SUBTITLE Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder 5a. CONTRACT NUMBER 5b

  1. Playing a zero-sum game?

    DEFF Research Database (Denmark)

    Triantafillou, Peter

    2017-01-01

    Supreme audit institutions (SAIs) are fundamental institutions in liberal democracies as they enable control of the exercise of state power. In order to maintain this function, SAIs must enjoy a high level of independence. Moreover, SAIs are increasingly expected to be also relevant for government...... and the execution of its policies by way of performance auditing. This article examines how and why the performance auditing of the Danish SAI pursues independence and relevance. It is argued that, in general, the simultaneous pursuit of independence and relevance is highly challenging and amounts to a zero-sum or...

  2. Considerações sobre a prevalência dos tratados internacionais sobre a legislação tributária brasileira: o caso do MERCOSUL

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Ribeiro

    1997-12-01

    Full Text Available This is a study on the main aspects discussed in the Brazilian doctrine and the jurisprudence concerning the prevalence of international treaties and conventions for internal tax legislation. Considerations are made on the Brazilian federate and sovereignty principles and on the competence constitutionally established for all the political entities of the Brazilian State. Article 151, section III of the Federal Constitution must be pointed out for its purpose on stating that the Union shall not exempt the States, the Federal District and the Municipalities from respective taxes. Article 98 of the National Tax Code is also considered for its disposition concerning legislation from international treaties and agreements on tax norms of the positive system currently in force.Trata-se de estudo sobre os principais aspectos discutidos na doutrina e na jurisprudência brasileira sobre a prevalência dos tratados e convenções internacionais sobre a legislação tributária interna. Necessário se faz apresentar considerações sobre o princípio federativo brasileiro, o princípio da soberania e o da competência constitucionalmente estabelecida para todos os entes políticos do Estado brasileiro. Merece maior destaque o art. 151, inciso III da Constituição Federal ao enaltecer que a União não poderá conceder isenções de tributos de competência dos Estados, Distrito Federal e Municípios, bem como a análise do art. 98 do Código Tributário Nacional dispondo sobre as introduções legislativas provenientes de tratados e acordos internacionais sobre as normas tributárias do sistema positivo vigente.

  3. Etnografiando travestis: preguntas, tensiones y aprendizajes sobre el "estar ahí"

    Directory of Open Access Journals (Sweden)

    María Soledad Cutuli

    Full Text Available Este artículo interroga la construcción de vínculos etnográficos en dos obras pioneras sobre travestis, con una intención retrospectiva sobre la propia investigación en una agrupación de travestis de Buenos Aires. Se reflexiona sobre la implicancia de los/as antropólogos/as "en campo" -en tanto seres sexuados/as y generizados/as- preguntándose además sobre las formas en que son interpeladas/os durante su labor junto a integrantes de organizaciones sociales -en la que el activismo resulta ser la extensión lógica del compromiso a la reciprocidad que subyace en la práctica antropológica.

  4. Morphologies of Sol–Gel Derived Thin Films of ZnO Using Different Precursor Materials and their Nanostructures

    Directory of Open Access Journals (Sweden)

    Chandra Sudhir

    2007-01-01

    Full Text Available AbstractWe have shown that the morphological features of the sol–gel derived thin films of ZnO depend strongly on the choice of the precursor materials. In particular, we have used zinc nitrate and zinc acetate as the precursor materials. While the films using zinc acetate showed a smoother topography, those prepared by using zinc nitrate exhibited dendritic character. Both types of films were found to be crystalline in nature. The crystallite dimensions were confined to the nanoscale. The crystallite size of the nanograins in the zinc nitrate derived films has been found to be smaller than the films grown by using zinc acetate as the precursor material. Selected area electron diffraction patterns in the case of both the precursor material has shown the presence of different rings corresponding to different planes of hexagonal ZnO crystal structure. The results have been discussed in terms of the fundamental considerations and basic chemistry governing the growth kinetics of these sol–gel derived ZnO films with both the precursor materials.

  5. DISCUTINDO SOBRE SEXTING

    Directory of Open Access Journals (Sweden)

    Suzana da Conceição de Barros

    2013-07-01

    Full Text Available Na contemporaneidade, os sujeitos vêm se utilizando das diversas tecnologias digitais, para exporem e compartilharem sua intimidade, com intuito de seduzirem e tornarem-se visíveis. Esse fenômeno vem sendo chamado de sexting, e vem sendo aderido por sujeitos de várias faixas etárias. Assim, leitor/a, convido você a pensar sobre o sexting e o que a escola tem a ver com essa prática?

  6. Core damage frequency estimation using accident sequence precursor data: 1990-1993

    International Nuclear Information System (INIS)

    Martz, H.F.

    1998-01-01

    The Nuclear Regulatory Commission's (NRC's) ongoing Accident Sequence Precursor (ASP) program uses probabilistic risk assessment (PRA) techniques to assess the potential for severe core damage (henceforth referred to simply as core damage) based on operating events. The types of operating events considered include accident sequence initiators, safety equipment failures, and degradation of plant conditions that could increase the probability that various postulated accident sequences occur. Such operating events potentially reduce the margin of safety available for prevention of core damage an thus can be considered as precursors to core damage. The current process for identifying, analyzing, and documenting ASP events is described in detail in Vanden Heuval et al. The significance of a Licensee Event Report (LER) event (or events) is measured by means of the conditional probability that the event leads to core damage, the so-called conditional core damage probability or, simply, CCDP. When the first ASP study results were published in 1982, it covered the period 1969--1979. In addition to identification and ranking of precursors, the original study attempted to estimate core damage frequency (CDF) based on the precursor events. The purpose of this paper is to compare the average annual CDF estimates calculated using the CCDP sum, Cooke-Goossens, Bier, and Abramson estimators for various reactor classes using the combined ASP data for the four years, 1990--1993. An important outcome of this comparison is an answer to the persistent question regarding the degree and effect of the positive bias of the CCDP sum method in practice. Note that this paper only compares the estimators with each other. Because the true average CDF is unknown, the estimation error is also unknown. Therefore, any observations or characterizations of bias are based on purely theoretical considerations

  7. Fabrication of superconducting wire using organometallic precursors and infiltration

    International Nuclear Information System (INIS)

    Lee, Y.J.

    1991-01-01

    Organometallic precursors from naphthenic acid and metal nitrates were used for the synthesis of YBCO oxide superconducting compounds. The characteristics of metal naphthenates as organometallic precursors were investigated by IR spectra, viscosity measurements, and infiltration. 123 superconducting compound obtained from 123 naphthenate showed a Tc of 90 degree K and a rather dense and elongated microstructure. Also, the melting behavior of Ba-cuprates which were used for 123 making was studied. A low-temperature melting process was developed to fabricate silver-sheathed superconducting wire with the powder-in-tube method; flowing argon gas is introduced to the system at 930-945 degree C to reduce the melting temperature of the 123 compound without silver sheath melting. It resulted in a 90 degree K Tc superconducting core with dense and locally aligned microstructure. SEM-EDS and XRD analysis, 4-probe resistance and Jc measurements, and carbon-content determinations were carried out to characterize the microstructure, grain alignment, and superconducting properties of the samples

  8. Quantitative analysis of mineral powders by DRIFTS: Determination of SrCO3 in superconductor precursor powders

    DEFF Research Database (Denmark)

    Bak, J.; Kindl, B.

    1997-01-01

    An application of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) has been demonstrated to be able to determine small concentrations, down to the 100-ppm level, of carbonates in powdery superconductor (SPC) precursor samples, The detection of carbonates in SPC precursor powders...

  9. Validation of Measures of Biosocial Precursors to Borderline Personality Disorder: Childhood Emotional Vulnerability and Environmental Invalidation

    Science.gov (United States)

    Sauer, Shannon E.; Baer, Ruth A.

    2010-01-01

    Linehan's biosocial theory suggests that borderline personality disorder (BPD) results from a transaction of two childhood precursors: emotional vulnerability and an invalidating environment. Until recently, few empirical studies have explored relationships between these theoretical precursors and symptoms of the disorder. Psychometrically sound…

  10. Precursors to potential severe core damage accidents: 1994, a status report. Volume 21: Main report and appendices A--H

    International Nuclear Information System (INIS)

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Vanden Heuvel, L.N.; Dolan, B.W.; Minarick, J.W.

    1995-12-01

    Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 x 10 -6 . These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1

  11. Efeito de adição de diferentes sais de cálcio nas características da massa e na elaboração de pão francês

    Directory of Open Access Journals (Sweden)

    Kajishima Shizuko

    2003-01-01

    Full Text Available O objetivo deste trabalho foi estudar os efeitos da adição do sulfato de cálcio, carbonato de cálcio e fosfato de cálcio dibásico nas características físicas e reológicas da farinha de trigo e na qualidade de pão francês. Utilizou-se a quantidade de sais de cálcio que correspondesse a 100% da IDR de adulto por 100g de pão. Na farinha foram realizadas análises de cor, teor de glúten, farinografia, alveografia e extensigrafia. O pão francês elaborado foi analisado quanto a seu volume específico e conceito global. O enriquecimento com cálcio melhorou a cor da farinha e os resultados satisfatórios obtidos na reologia das massas e com os pães mostraram que se pode utilizar qualquer uma das três fontes para se elaborar pão enriquecido com cálcio.

  12. The Chemistry of Inorganic Precursors during the Chemical Deposition of Films on Solid Surfaces.

    Science.gov (United States)

    Barry, Seán T; Teplyakov, Andrew V; Zaera, Francisco

    2018-03-20

    The deposition of thin solid films is central to many industrial applications, and chemical vapor deposition (CVD) methods are particularly useful for this task. For one, the isotropic nature of the adsorption of chemical species affords even coverages on surfaces with rough topographies, an increasingly common requirement in microelectronics. Furthermore, by splitting the overall film-depositing reactions into two or more complementary and self-limiting steps, as it is done in atomic layer depositions (ALD), film thicknesses can be controlled down to the sub-monolayer level. Thanks to the availability of a vast array of inorganic and metalorganic precursors, CVD and ALD are quite versatile and can be engineered to deposit virtually any type of solid material. On the negative side, the surface chemistry that takes place in these processes is often complex, and can include undesirable side reactions leading to the incorporation of impurities in the growing films. Appropriate precursors and deposition conditions need to be chosen to minimize these problems, and that requires a proper understanding of the underlying surface chemistry. The precursors for CVD and ALD are often designed and chosen based on their known thermal chemistry from inorganic chemistry studies, taking advantage of the vast knowledge developed in that field over the years. Although a good first approximation, however, this approach can lead to wrong choices, because the reactions of these precursors at gas-solid interfaces can be quite different from what is seen in solution. For one, solvents often aid in the displacement of ligands in metalorganic compounds, providing the right dielectric environment, temporarily coordinating to the metal, or facilitating multiple ligand-complex interactions to increase reaction probabilities; these options are not available in the gas-solid reactions associated with CVD and ALD. Moreover, solid surfaces act as unique "ligands", if these reactions are to be

  13. Development of precursors recognition methods in vector signals

    Science.gov (United States)

    Kapralov, V. G.; Elagin, V. V.; Kaveeva, E. G.; Stankevich, L. A.; Dremin, M. M.; Krylov, S. V.; Borovov, A. E.; Harfush, H. A.; Sedov, K. S.

    2017-10-01

    Precursor recognition methods in vector signals of plasma diagnostics are presented. Their requirements and possible options for their development are considered. In particular, the variants of using symbolic regression for building a plasma disruption prediction system are discussed. The initial data preparation using correlation analysis and symbolic regression is discussed. Special attention is paid to the possibility of using algorithms in real time.

  14. Deposition on disordered substrates with precursor layer diffusion

    Science.gov (United States)

    Filipe, J. A. N.; Rodgers, G. J.; Tavassoli, Z.

    1998-09-01

    Recently we introduced a one-dimensional accelerated random sequential adsorption process as a model for chemisorption with precursor layer diffusion. In this paper we consider this deposition process on disordered or impure substrates. The problem is solved exactly on both the lattice and continuum and for various impurity distributions. The results are compared with those from the standard random sequential adsorption model.

  15. Synthesis of beta alumina from aluminum hydroxide and oxyhydroxide precursors

    CSIR Research Space (South Africa)

    Van Zyl, A

    1993-02-01

    Full Text Available Two aluminium oxyhydroxides, boehmite and pseudoboehmite, and two aluminium hydroxides, bayerite and gibbsite, have been investigated as precursors for the synthesis of the solid electrolyte, beta alumina. Reaction pathways and products have been...

  16. A comparison of chemical structures of soot precursor nanoparticles from liquid fuel combustion in flames and engine

    International Nuclear Information System (INIS)

    Paul, Bireswar; Datta, Amitava; Datta, Aparna; Saha, Abhijit

    2013-01-01

    A comparative study of the chemical structures of soot precursor nanoparticles from the liquid fuel flame and engine exhaust has been performed in this work to establish an association between the particles from both the sources. Different ex-situ measurement techniques have been used to characterize the nanoparticles in samples collected from the laboratory petrol/air and iso-octane/air flames, as well as from a gasoline engine. The TEM images of the sampled material along with the EDS spectra corroborate the existence of carbonaceous nanoparticles. The nature of the UV absorption and fluorescence spectra of the samples from the iso-octane flame environment further confirms the sampled materials to be soot precursor nanoparticles. The DLS size distribution of the particles shows them to be below 10 nm size. FTIR spectrum of the precursor nanoparticles collected form the non-sooting zone of the flame and that of fully grown soot particles show few similarities and dissimilarities among them. The soot particles are found to be much more aromatized as compared to its precursor nanoparticles. The presence of carbonyl functional group (C=O) at around 1,720 cm −1 has been observed in soot precursor nanoparticles, while such oxygenated functional groups are not prominent in soot structure. The absorption (UV and IR) and fluorescence spectra of the carbonaceous material collected from the gasoline engine exhaust show many resemblances with those of soot precursor nanoparticles from flames. These spectroscopic resemblances of the soot precursor nanoparticles from the flame environment and engine exhaust gives the evidence that the in-cylinder combustion is the source of these particles in the engine exhaust.

  17. Perspectivas sobre la China contemporánea en la prensa española sobre Relaciones Internacionales (2000-2012)

    OpenAIRE

    Cocina Díaz, Rodrigo

    2013-01-01

    Un estudio de las perspectivas sobre los últimos años de la evolución histórica de China desde varias fuentes especializadas en política internacional publicadas en España, entre el año 2000 y el 2012, que incluye un análisis sobre el número de artículos publicados a lo largo del tiempo, donde se refleja la evolución del interés por el tema en dichas fuentes. Se han utilizado las revistas Política Exterior, CIDOB d'afers Internacionals, Le Monde Diplomatique en español, y la web del Observato...

  18. Liberalismo versus republicanismo: notas sobre o conceito de liberdade.

    Directory of Open Access Journals (Sweden)

    Felipe Nunes

    2007-01-01

    Full Text Available Este artigo tem como objetivo contrastar as perspectivas liberal e republicana sobre o conceito de liberdade. Através da comparação feita entre os dois modelos tecemos considerações sobre a realidade brasileira tendo como foco o atual estado de crises advindas dos casos de corrupção no país.

  19. Processing and characterization of yttrium-stabilized zirconia thin films on polyimide from aqueous polymeric precursors

    International Nuclear Information System (INIS)

    Gorman, B.P.; Anderson, H.U.

    2004-01-01

    Low-temperature deposition of dense, nanocrystalline yttrium-stabilized zirconia (YSZ) thin films on polyimide (PI) substrates is illustrated using an aqueous polymeric precursor spin-coating technique. The polymeric precursor uses low-cost materials, is water-soluble and the viscosity and cation concentrations can be easily adjusted in order to vary the film thickness from 0.02 to 0.3 μm. Due to the use of water as the solvent in the YSZ precursor and the hydrophobic nature of the PI surface, surface modification processes were utilized in order to improve the wetting characteristics. Surface modification of PI substrates using wet chemical and oxygen plasma techniques led to a decrease in the precursor contact angle, and ultimately allowed for uniform film formation on both bulk and thin film PI substrates. Scanning electron microscopy, transmission electron microscopy and UV/Vis absorption illustrate that near full-density nanocrystalline thin films of YSZ can be produced at temperatures as low as 350 deg. C. Thermogravimetric analyses illustrate that the PI substrate does not undergo any weight loss up to these temperatures

  20. Preparación y caracterización de la zeolita MCM-22 y de su precursor laminar

    Directory of Open Access Journals (Sweden)

    Pergher Sibele B. C.

    2003-01-01

    Full Text Available The layered precursor of MCM-22 was prepared with different Si/Al ratios: 15, 25, 50, 100 and ¥. Upon heat treatment these precursors form MCM-22 zeolite. Both layered precursor and MCM-22 zeolite were characterized by several techniques: Chemical Analysis by Atomic Absorption Spectroscopy (AAS, X-Ray Diffraction (XRD, Thermo-gravimetric Analysis (TGA, Pore Analysis by N2 and Ar adsorption, Scanning Electron Microscopy (SEM, Infrared Spectroscopy (IR and Temperature Programmed Desorption of ammonium (TPD.

  1. Effects of Chemical Curing Temperature and Time on the Properties of Liquefied Wood based As-cured Precursors and Carbon Fibers

    Directory of Open Access Journals (Sweden)

    Junbo Shang

    2015-09-01

    Full Text Available Liquefied wood based as-cured precursors and carbon fibers prepared by different chemical curing processes were carried out to investigate the effects of curing temperature and time on the thermostability and microstructure of liquefied wood based precursors, the tensile strength of carbon fibers as well. The primary fibers can be converted into precursors with high performance by directly heating at target curing temperature. With the temperature and duration increasing, the numbers of methylene bonds in precursors increased, resulting in the enhancement of cross-linkages among molecular chains and then the improvement of thermostability of precursors. Carbon fibers prepared from as-cured precursors (curing temperature 95 oC, curing time 3h had the minimum value of the average interlayer spacing (d002, it also showed the highest tensile strength, almost 800 MPa, which can be classified as fibers of general grade.

  2. Seguridad en redes y sistemas : Técnicas y conceptos sobre hacking y pentesting

    OpenAIRE

    Jiménez Jiménez, Cristian

    2016-01-01

    El siguiente documento trata sobre seguridad informática. Se detallarán técnicas y conceptos sobre seguridad en redes y sistemas, pentesting y auditorías de seguridad. El següent document tracta sobre seguretat informàtica. Es detallaran tècniques i conceptes sobre seguretat en xarxes i sistemes, pentesting i auditories de seguretat. The following document is about computer security. Techniques and network security concepts and systems, pentesting and safety practices will be described....

  3. Lunar Robotic Precursor Missions Using Electric Propulsion

    OpenAIRE

    Winski, Richard G.

    2006-01-01

    A trade study is carried out for the design of electric propulsion based lunar robotic precursor missions. The focus is to understand the relationships between payload mass delivered, electric propulsion power, and trip time. The results are compared against a baseline system using chemical propulsion with LOX/H2. The major differences between the chemical propulsion based and electric propulsion based systems are presented in terms of the payload mass and trip time. It is shown that solar e...

  4. Multiplicação e enraizamento in vitro de amoreira-preta 'Xavante': efeito da concentração de sais, do tipo de explante e de carvão ativado no meio de cultura Blackberry 'Xavante' in vitro multiplication and rooting: salt concentrations effect, explant type, and activated coal on culture medium

    Directory of Open Access Journals (Sweden)

    Luciane Nolasco Leitzke

    2009-01-01

    Full Text Available Atualmente, além da propagação tradicional, a micropropagação da amoreira-preta é considerada uma alternativa viável, com o intuito de obter-se plantas livres de vírus, geneticamente uniformes e em curto espaço de tempo. Objetivou-se, com este experimento, determinar o melhor tipo de explante e concentração de sais para a multiplicação in vitro e a melhor concentração de carvão ativado e de sais no meio de cultura, para o enraizamento in vitro de amoreira-preta 'Xavante'. O primeiro experimento constituiu-se de segmentos nodais caulinares com cerca de 1 cm, oriundas do cultivo in vitro, inoculadas em quatro diferentes concentrações de meio MS, suplementada com 7,5 µM de BAP, 30 g L-1 de sacarose, 100 mg L-1 de mio-inositol e 6 g L-1 de ágar, e dois tipos de explante, totalizando 8 tratamentos. O segundo experimento constituiu-se de microestacas apicais, com cerca de 1 a 1,5 cm de comprimento, e duas folhas, inoculadas em três diferentes concentrações de meio MS, acrescido de 30 g L-1 de sacarose, 100 mg L-1 de mio-inositol e 6 g L-1 de ágar e suplementado com três concentrações de carvão ativado, totalizando nove tratamentos, com delineamento inteiramente casualizado. Pode-se concluir que o T1, ou seja, explante com folhas, na concentração de 125% de sais do meio MS foi mais eficiente, induzindo maior número de folhas, gemas, brotações e comprimento das brotações e que o uso de 75% de sais sem a suplementação de carvão ativado é o mais indicado para o enraizamento in vitro de amoreira-preta 'Xavante'.Besides the traditional propagation, blackberry micropropagation has currently been considered a feasible alternative, with the purpose of obtaining plants free from virus, genetically uniform and in the short run. The objective of this experiment was to determine the best explant type and the optimum in vitro multiplication salts concentration as well as to determine the activated coal and salts optimum

  5. Thermal conductivity of high-porosity biocarbon precursors of white pine wood

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Kartenko, N. F.; Sharenkova, N. V.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Jezowski, A.; Wilkes, T. E.; Faber, K. T.

    2008-12-01

    This paper reports on measurements of the thermal conductivity κ and the electrical conductivity σ of high-porosity (cellular pores) biocarbon precursors of white pine tree wood in the temperature range 5-300 K, which were prepared by pyrolysis of the wood at carbonization temperatures ( T carb) of 1000 and 2400°C. The x-ray structural analysis has permitted the determination of the sizes of the nanocrystallites contained in the carbon framework of the biocarbon precursors. The sizes of the nanocrystallites revealed in the samples prepared at T carb = 1000 and 2400°C are within the ranges 12-35 and 25-70 Å, respectively. The dependences κ( T) and σ( T) are obtained for samples cut along the tree growth direction. As follows from σ( T) measurements, the biocarbon precursors studied are semiconducting. The values of κ and σ increase with increasing carbonization temperature of the samples. Thermal conductivity measurements have revealed that samples of both types exhibit a temperature dependence of the phonon thermal conductivity κph, which is not typical of amorphous (and amorphous to x-rays) materials. As the temperature increases, κph first varies proportional to T, to scale subsequently as ˜ T 1.7. The results obtained are analyzed.

  6. Large-scale preparation of active caspase-3 in E. coli by designing its thrombin-activatable precursors

    Directory of Open Access Journals (Sweden)

    Park Sung

    2008-12-01

    Full Text Available Abstract Background Caspase-3, a principal apoptotic effector that cleaves the majority of cellular substrates, is an important medicinal target for the treatment of cancers and neurodegenerative diseases. Large amounts of the protein are required for drug discovery research. However, previous efforts to express the full-length caspase-3 gene in E. coli have been unsuccessful. Results Overproducers of thrombin-activatable full-length caspase-3 precursors were prepared by engineering the auto-activation sites of caspase-3 precursor into a sequence susceptible to thrombin hydrolysis. The engineered precursors were highly expressed as soluble proteins in E. coli and easily purified by affinity chromatography, to levels of 10–15 mg from 1 L of E. coli culture, and readily activated by thrombin digestion. Kinetic evaluation disclosed that thrombin digestion enhanced catalytic activity (kcat/KM of the precursor proteins by two orders of magnitude. Conclusion A novel method for a large-scale preparation of active caspase-3 was developed by a strategic engineering to lack auto-activation during expression with amino acid sequences susceptible to thrombin, facilitating high-level expression in E. coli. The precursor protein was easily purified and activated through specific cleavage at the engineered sites by thrombin, generating active caspase-3 in high yields.

  7. Pig epidermal growth factor precursor contains segments that are highly conserved among species

    DEFF Research Database (Denmark)

    Jørgensen, P E; Jensen, L.G.; Sørensen, B S

    1998-01-01

    segment with that of the human, the rat and the mouse EGF precursors, in order to identify highly conserved domains. The examined part of the precursor contains EGF itself and six so-called EGF-like modules. The overall amino acid identity among the four species is 64%. However, the amino acid identity...... differed from around 30% in some segments to around 70% in others. The highest amino acid identity, 71%, was observed for a 345-aa segment that contains three EGF-like modules and which is homologous to a part of the low-density lipoprotein receptor (LDL receptor). The amino acid identities are 64% for EGF...... itself, and 50-67% for the remaining three EGF-like modules. The segment of the LDL receptor that is homologous to a part of the EGF precursor is important for the function of the LDL receptor, and EGF-like modules seem to be involved in protein-protein interactions in a number of proteins. In conclusion...

  8. Direct Genesis of Functional Rodent and Human Schwann Cells from Skin Mesenchymal Precursors

    Directory of Open Access Journals (Sweden)

    Matthew P. Krause

    2014-07-01

    Full Text Available Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs, a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.

  9. Two pheromone precursor genes are transcriptionally expressed in the homothallic ascomycete Sordaria macrospora.

    Science.gov (United States)

    Pöggeler, S

    2000-06-01

    In order to analyze the involvement of pheromones in cell recognition and mating in a homothallic fungus, two putative pheromone precursor genes, named ppg1 and ppg2, were isolated from a genomic library of Sordaria macrospora. The ppg1 gene is predicted to encode a precursor pheromone that is processed by a Kex2-like protease to yield a pheromone that is structurally similar to the alpha-factor of the yeast Saccharomyces cerevisiae. The ppg2 gene encodes a 24-amino-acid polypeptide that contains a putative farnesylated and carboxy methylated C-terminal cysteine residue. The sequences of the predicted pheromones display strong structural similarity to those encoded by putative pheromones of heterothallic filamentous ascomycetes. Both genes are expressed during the life cycle of S. macrospora. This is the first description of pheromone precursor genes encoded by a homothallic fungus. Southern-hybridization experiments indicated that ppg1 and ppg2 homologues are also present in other homothallic ascomycetes.

  10. Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder

    Science.gov (United States)

    2017-12-01

    AWARD NUMBER: W81XWH-14-1-0527 TITLE: Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder...2017 4. TITLE AND SUBTITLE Precursors to the Development of Anxiety Disorders in Young Children with Autism Spectrum Disorder 5a. CONTRACT NUMBER 5b...neurophysiological, and observational measures. Initial findings indicate that children with ASD who have clinically significant sensory are at increased risk for

  11. UN MODELO SOBRE CÓMO LAS ESTRATEGIAS MOTIVACIONALES RELACIONADAS CON EL COMPONENTE DE AFECTIVIDAD INCIDEN SOBRE LAS ESTRATEGIAS COGNITIVAS Y METACOGNITIVAS

    Directory of Open Access Journals (Sweden)

    José Manuel Suárez Riveiro

    2013-01-01

    Full Text Available El principal propósito de este trabajo fue el de proponer un modelo sobre cómo las estrategias motivacionales relacionadas al componente de afectividad inciden sobre la utilización de las estrategias cognitivas y metacognitivas. La muestra utilizada fue de 500 estudiantes de Secundaria. Se asumió que el efecto de las estrategias motivacionales sobre las estrategias cognitivas estaría mediado por el uso de las estrategias metacognitivas. Para estudiar estas estrategias y su relación se realizaron análisis descriptivos y se elaboró un diagrama de senderos. Los resultados mostraron que la estrategia motivacional más utilizada es la de autorrefuerzo y que se establecen relaciones significativas desde algunas estrategias motivacionales, pero no desde todas, con las estrategias cognitivas aunque únicamente la estrategia de autorrefuerzo establece relaciones significativas con la autorregulación metacognitiva.

  12. Oxidation of suspected N-nitrosodimethylamine (NDMA) precursors by ferrate (VI): kinetics and effect on the NDMA formation potential of natural waters.

    Science.gov (United States)

    Lee, Changha; Lee, Yunho; Schmidt, Carsten; Yoon, Jeyong; Von Gunten, Urs

    2008-01-01

    The potential of ferrate (Fe(VI)) oxidation to remove N-nitrosodimethylamine (NDMA) precursors during water treatment was assessed. Apparent second-order rate constants (k(app)) for the reactions of NDMA and its suspected precursors (dimethylamine (DMA) and 7 tertiary amines with DMA functional group) with Fe(VI) were determined in the range of pH 6-12. Four model NDMA precursors (dimethyldithiocarbamate, dimethylaminobenzene, 3-(dimethylaminomethyl)indole and 4-dimethylaminoantipyrine) showed high reactivity toward Fe(VI) with k(app) values at pH 7 between 2.6 x 10(2) and 3.2 x 10(5)M(-1)s(-1). The other NDMA precursors (DMA, trimethylamine, dimethylethanolamine, dimethylformamide) and NDMA had k(app) values ranging from 0.55 to 9.1M(-1)s(-1) at pH 7. In the second part of the study, the NDMA formation potentials (NDMA-FP) of the model NDMA precursors and natural waters were measured with and without pre-oxidation by Fe(VI). For most of the NDMA precursors with the exception of DMA, a significant reduction of the NDMA-FP (>95%) was observed after complete transformation of the NDMA precursor. This result was supported by low yields of DMA from the Fe(VI) oxidation of tertiary amine NDMA precursors. Pre-oxidation of several natural waters (rivers Rhine, Neckar and Pfinz) with a high dose of Fe(VI) (0.38 mM = 21 mg L(-1) as Fe) led to removals of the NDMA-FP of 46-84%. This indicates that the NDMA precursors in these waters have a low reactivity toward Fe(VI) because it has been shown that for fast-reacting NDMA precursors Fe(VI) doses of 20 microM (1.1 mg L(-1) as Fe) are sufficient to completely oxidize the precursors.

  13. Annotation of novel neuropeptide precursors in the migratory locust based on transcript screening of a public EST database and mass spectrometry

    Directory of Open Access Journals (Sweden)

    De Loof Arnold

    2006-08-01

    Full Text Available Abstract Background For holometabolous insects there has been an explosion of proteomic and peptidomic information thanks to large genome sequencing projects. Heterometabolous insects, although comprising many important species, have been far less studied. The migratory locust Locusta migratoria, a heterometabolous insect, is one of the most infamous agricultural pests. They undergo a well-known and profound phase transition from the relatively harmless solitary form to a ferocious gregarious form. The underlying regulatory mechanisms of this phase transition are not fully understood, but it is undoubtedly that neuropeptides are involved. However, neuropeptide research in locusts is hampered by the absence of genomic information. Results Recently, EST (Expressed Sequence Tag databases from Locusta migratoria were constructed. Using bioinformatical tools, we searched these EST databases specifically for neuropeptide precursors. Based on known locust neuropeptide sequences, we confirmed the sequence of several previously identified neuropeptide precursors (i.e. pacifastin-related peptides, which consolidated our method. In addition, we found two novel neuroparsin precursors and annotated the hitherto unknown tachykinin precursor. Besides one of the known tachykinin peptides, this EST contained an additional tachykinin-like sequence. Using neuropeptide precursors from Drosophila melanogaster as a query, we succeeded in annotating the Locusta neuropeptide F, allatostatin-C and ecdysis-triggering hormone precursor, which until now had not been identified in locusts or in any other heterometabolous insect. For the tachykinin precursor, the ecdysis-triggering hormone precursor and the allatostatin-C precursor, translation of the predicted neuropeptides in neural tissues was confirmed with mass spectrometric techniques. Conclusion In this study we describe the annotation of 6 novel neuropeptide precursors and the neuropeptides they encode from the

  14. Contabilidad de Costos I. - Problemas sobre contabilización de las actividades relacionadas con los materiales

    OpenAIRE

    Morillo Moreno, Marysela C.

    2008-01-01

    ÍNDICE Introducción Problemas sobre terminología básica Problemas básicos sobre el Ciclo de la Contabilidad de Costos Problemas sobre contabilización de las actividades relacionadas con los materiales Problemas sobre la contabilización de las actividades relacionadas con la mano de obra Problemas sobre la contabilización de las actividades relacionadas con los costos indirectos de fabricación Problemas sobre el Ciclo de la Contabilida...

  15. High-quality CdTe films from nanoparticle precursors

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, D.L.; Pehnt, M.; Urgiles, E. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    In this paper the authors demonstrate that nanoparticulate precursors coupled with spray deposition offers an attractive route into electronic materials with improved smoothness, density, and lower processing temperatures. Employing a metathesis approach, cadmium iodide was reacted with sodium telluride in methanol solvent, resulting in the formation of soluble NaI and insoluble CdTe nanoparticles. After appropriate chemical workup, methanol-capped CdTe colloids were isolated. CdTe thin film formation was achieved by spray depositing the nanoparticle colloids (25-75 {Angstrom} diameter) onto substrates at elevated temperatures (T = 280-440{degrees}C) with no further thermal treatment. These films were characterized by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Cubic CdTe phase formation was observed by XRD, with a contaminant oxide phase also detected. XPS analysis showed that CdTe films produced by this one-step method contained no Na or C and substantial O. AFM gave CdTe grain sizes of {approx}0.1-0.3 {mu}m for film sprayed at 400{degrees}C. A layer-by-layer film growth mechanism proposed for the one-step spray deposition of nanoparticle precursors will be discussed.

  16. Silicone Resin Applications for Ceramic Precursors and Composites

    Directory of Open Access Journals (Sweden)

    Masaki Narisawa

    2010-06-01

    Full Text Available This article reviews the applications of silicone resins as ceramic precursors. The historical background of silicone synthesis chemistry is introduced to explain the production costs and supply availability of various silicones. Thermal degradation processes of silicones are classified in terms of the main chain structure and cyclic oligomer expulsion process, which determine the resulting ceramic yield and the chemical composition. The high temperature decomposition of Si-O-C beyond 1,400 °C in an inert atmosphere and formation of a protective silica layer on material surfaces beyond 1,200 °C in an oxidative atmosphere are discussed from the viewpoints of the wide chemical composition of the Si-O-C materials. Applications of the resins for binding agents, as starting materials for porous ceramics, matrix sources with impregnation, fiber spinning and ceramic adhesions are introduced. The recent development of the process of filler or cross-linking agent additions to resin compounds is also introduced. Such resin compounds are useful for obtaining thick coatings, MEMS parts and bulk ceramics, which are difficult to obtain by pyrolysis of simple organometallic precursors without additives.

  17. Occurrence of THM and NDMA precursors in a watershed: Effect of seasons and anthropogenic pollution.

    Science.gov (United States)

    Aydin, Egemen; Yaman, Fatma Busra; Ates Genceli, Esra; Topuz, Emel; Erdim, Esra; Gurel, Melike; Ipek, Murat; Pehlivanoglu-Mantas, Elif

    2012-06-30

    In pristine watersheds, natural organic matter is the main source of disinfection by-product (DBP) precursors. However, the presence of point or non-point pollution sources in watersheds may lead to increased levels of DBP precursors which in turn form DBPs in the drinking water treatment plant upon chlorination or chloramination. In this study, water samples were collected from a lake used to obtain drinking water for Istanbul as well as its tributaries to investigate the presence of the precursors of two disinfection by-products, trihalomethanes (THM) and N-nitrosodimethylamine (NDMA). In addition, the effect of seasons and the possible relationships between these precursors and water quality parameters were evaluated. The concentrations of THM and NDMA precursors measured as total THM formation potential (TTHMFP) and NDMA formation potential (NDMAFP) ranged between 126 and 1523μg/L THM and NDMA, respectively. Such wide ranges imply that some of the tributaries are affected by anthropogenic pollution sources, which is also supported by high DOC, Cl(-) and NH(3) concentrations. No significant correlation was found between the water quality parameters and DBP formation potential, except for a weak correlation between NDMAFP and DOC concentrations. The effect of the sampling location was more pronounced than the seasonal variation due to anthropogenic pollution in some tributaries and no significant correlation was obtained between the seasons and water quality parameters. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. The elusive indigo precursors in woad (Isatis tinctoria L.)--identification of the major indigo precursor, isatan A, and a structure revision of isatan B.

    Science.gov (United States)

    Oberthür, Christine; Schneider, Bernd; Graf, Heidemarie; Hamburger, Matthias

    2004-01-01

    A metabolite-profiling study of shock-frozen leaves of Isatis tinctoria L., an old indigo dye plant and medicinal herb, revealed a complex pattern of indigo-forming compounds with higher polarities than the known indigo precursors isatan B and indican. These highly unstable compounds underwent rapid post-harvest transformation and were not detected in air-dried leaves. The major indigo precursor, named isatan A (4), was isolated by rapid normal-phase and gel chromatography, along with isatan B (3). A full spectral data set of 3 showed that the previous structure assignment as 'indoxyl-5-ketogluconate' has to be revised to 1H-indol-3-yl beta-D-ribohex-3-ulopyranoside. Isatan A (4) was identified as 1H-indol-3-yl 6'-O-(carboxyacetyl)-beta-D-ribohex-3'-ulopyranoside. In aqueous solution, glycosides 3 and 4 occur as hydrates and undergo rapid hydrolysis under very mild acidic or basic conditions.

  19. Creep and slip: Seismic precursors to the Nuugaatsiaq landslide (Greenland)

    Science.gov (United States)

    Poli, Piero

    2017-09-01

    Precursory signals to material's failure are predicted by numerical models and observed in laboratory experiments or using field data. These precursory signals are a marker of slip acceleration on weak regions, such as crustal faults. Observation of these precursory signals of catastrophic natural events, such as earthquakes and landslides, is necessary for improving our knowledge about the physics of the nucleation process. Furthermore, observing such precursory signals may help to forecast these catastrophic events or reduce their hazard. I report here the observation of seismic precursors to the Nuugaatsiaq landslide in Greenland. Time evolution of the detected precursors implies that an aseismic slip event is taking place for hours before the landslide, with an exponential increase of slip velocity. Furthermore, time evolution of the precursory signals' amplitude sheds light on the evolution of the fault physics during the nucleation process.

  20. Controlled synthesis of ZnO hollow microspheres via precursor-template method and its gas sensing property

    International Nuclear Information System (INIS)

    Tian, Yu; Li, Jinchai; Xiong, Hui; Dai, Jiangnan

    2012-01-01

    Highlights: ► Zn powder as precursor template for synthesis ZnO hollow spheres. ► Different precursor templates result in different ZnO nanostructures. ► Different experimental conditions enable growth of different surface morphologies of ZnO sphere. ► ZnO hollow sphere materials have good gas sensing performance for detecting ethanol gas. - Abstract: Using Zn powder as precursor templates, ZnO hollow microspheres were successfully prepared by thermal evaporation method and characterized by X-ray diffraction analysis, scanning electron microscope and transmission electron microscope. It was found that different size and shape of precursor resulted in different ZnO nanostructures. When varying experimental conditions, such as air flow rate and working pressure, ZnO hollow spheres with different surface morphologies could be obtained. The advantages of the present synthetic technology are simple, relatively low cost, and high reproducibility. A gas sensor was fabricated from the as-prepared ZnO hollow microspheres and tested to the ethanol gas at different operating temperatures.

  1. Fabrication of compact and stable perovskite films with optimized precursor composition in the fast-growing procedure

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Tanghao; Zhou, Yuanyuan; Hu, Qin; Chen, Ke; Zhang, Yifei; Yang, Wenqiang; Wu, Jiang; Ye, Fengjun; Luo, Deying; Zhu, Kai; Padture, Nitin P.; Liu, Feng; Russell, Thomas; Zhu, Rui; Gong, Qihuang

    2017-06-02

    The fast-growing procedure (FGP) provides a simple, high-yield and lead (Pb)-release free method to prepare perovskite films. In the FGP, the ultra-dilute perovskite precursor solution is drop-cast onto a hot (~240 degrees C) substrate, where a perovskite film grows immediately accompanied by the rapid evaporation of the host solvent. In this process, all the raw materials in the precursor solution are deposited into the final perovskite film. The potential pollution caused by Pb can be significantly reduced. Properties of the FGP-processed perovskite films can be modulated by the precursor composition. While CH3NH3Cl (MACl) affects the crystallization process and leads to full surface coverage, CH(NH2)2I (FAI) enhances the thermal stability of the film. Based on the optimized precursor composition of PbI2(1-x)FAI xMACl, x=0.75, FGP-processed planar heterojunction perovskite solar cells exhibit power conversion efficiencies (PCEs) exceeding 15% with suppressed hysteresis and excellent reproducibility.

  2. Modifying action of DNA synthesis precursors on Aspergillus nidulans conidium irradiated by ultraviolet and X-rays

    International Nuclear Information System (INIS)

    Muronets, E.M.; Kameneva, S.V.

    1975-01-01

    Modification of inactivation action of radiation on conidia Aspergillus nidulans, UVS + and UVS strains, by desoxynucleosides, purine and pyrimidine bases is shown. The modification manifested in increased conidia survival is revealed when the precursor of DNA synthesis is added to the suspension before exposure to ultraviolet or X-rays. In the case of postradiation application of the substance no modification is observed. The modifying effect of different precursors becomes equally apparent with equimolar solutions and increases at higher concentration of the latter. An increase in thymidine endogenic pool in the exposed conidia does not affect their survival. When conidia are exposed to ultraviolet rays through a thymidine filter the survival rate increases to the same extent as in the case when they are exposed to irradiation in thymidine solution. The authors suggest that modification of the inactivating radiation action by DNA precursors at exposure of conidia Aspergillus nidulans is caused by the radioprotective effect of precursors not related to reparation [ru

  3. Degradation of typical N-nitrosodimethylamine (NDMA) precursors and its formation potential in anoxic-aerobic (AO) activated sludge system.

    Science.gov (United States)

    Wang, Lin; Li, Yongmei; He, Guodong

    2014-01-01

    N-nitrosodimethylamine (NDMA) is an emerging disinfection byproduct. Removal of its potential precursors is considered as an effective method to control NDMA. In this study, four typical NDMA precursors (dimethylamine (DMA), trimethylamine (TMA), dimethylformamide (DMFA) and dimethylaminobenzene (DMAB)) were selected, and their removal capacities by activated sludge were investigated. Batch experiments indicated that removal of NDMA precursors was better under aerobic condition than anoxic condition; and their specific degradation rates follow the order of DMA > TMA > DMFA > DMAB. In anoxic-aerobic (AO) activated sludge system, the optimal hydraulic retention time and sludge retention time were 10 h and 20 d, respectively, for the removal of both NDMA precursors (four selected NDMA precursors and NDMA formation potential (NDMA FP)) and nutrients. Our results also suggested that there was a positive correlation between NDMA FP and dissolved organic nitrogen (DON) in wastewater. The removal efficiency of NDMA FP was in the range of 46.8-72.5% in the four surveyed wastewater treatment plants except the one which adopted chemically enhanced primary process. The results revealed that the AO system had the advantage of removing NDMA FP. Our results are helpful for the knowledge of the removals of NDMA precursors during activated sludge treatment processes.

  4. The interleukin (IL-1a precursor is biologically active and is likely a key alarmin in the IL-1 family of cytokines

    Directory of Open Access Journals (Sweden)

    Busun eKim

    2013-11-01

    Full Text Available Among the eleven members of the IL-1 family cytokines, the precursors of IL-1a, IL-1b, and IL-33 have relatively long N-terminal pro-sequences of approximately one hundred amino acid residues prior to the N-terminus of the mature forms. Compared to the mature forms secreted from the cell, 80-90% of the primary translation product is in the intracellular compartment in the precursor form. However, the precursors are readily released from cells during infections but also with non-infectious conditions such a hypoxia and trauma. In this setting, the precursors act rapidly as alarmins in the absence of a processing mechanism to remove the pro-sequence and generate a mature form. In the case of IL-1a, the release of the precursor activates adjacent cells via receptor-mediated signaling. However, there are no data comparing the specific activity of the IL-1a precursor to the mature form. In the present study, we compared the precursor and mature forms of recombinant human IL-1a, IL-1b and IL-33 proteins on the induction of cytokines from A549 cells as well as from human peripheral blood mononuclear cells (PBMC. Similar to the mature form, the IL-1a precursor was active in inducing IL 6 and TNFa, whereas the precursor forms of IL 1b and IL-33 were not active. On PBMC, precursor and mature IL-1a at 0.04 and 0.2 nano-mole were equally active in inducing IL-6. Given the fact that during necrotic cell death, the IL-1a precursor is released intact and triggers IL-1 receptors on tissue macrophages, these data identify the precursor form of IL-1a as a key player in sterile inflammation.

  5. Developmental Dyslexia: Early Precursors, Neurobehavioral Markers, and Biological Substrates

    Science.gov (United States)

    Benasich, April A., Ed.; Fitch, R. Holly, Ed.

    2012-01-01

    Understanding the precursors and early indicators of dyslexia is key to early identification and effective intervention. Now there's a single research volume that brings together the very latest knowledge on the earliest stages of dyslexia and the diverse genetic, neurobiological, and cognitive factors that may contribute to it. Based on findings…

  6. NdRhSn: A ferromagnet with an antiferromagnetic precursor

    Czech Academy of Sciences Publication Activity Database

    Mihalik, M.; Prokleška, J.; Kamarád, Jiří; Prokeš, K.; Isnard, O.; McIntyre, G. J.; Dönni, A.; Yoshii, S.; Kitazawa, H.; Sechovský, V.; de Boer, F.R.

    2011-01-01

    Roč. 83, č. 10 (2011), "104403-1"-"104403-10" ISSN 1098-0121 R&D Projects: GA ČR GA202/09/1027 Institutional research plan: CEZ:AV0Z10100521 Keywords : NdRhSn * ferromagnet * antiferromagnetic precursor Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.691, year: 2011

  7. Investigación sobre implementación y gobernanza

    DEFF Research Database (Denmark)

    Cejudo,, Guillermo M.; May, Peter J.; Sætren, Harald

    2018-01-01

    . Cejudo, María del Carmen Pardo y Mauricio I. Dussauge Laguna (todos de la División de Ad­ministración Pública del CIDE), cerró con un panel sobre “investigación sobre implementación y gobernanza: direcciones y retos para el futuro”. Lo que sigue es una versión editada de esa discusión de clausura....

  8. Sobre manhãs, humor e atos de fala

    Directory of Open Access Journals (Sweden)

    Joana Plaza PINTO

    Full Text Available RESUMO Este ensaio apresenta uma trajetória de leituras de Frege a Austin, intermediadas pela interpretação independente e ousada de Kanavillil Rajagopalan. Ao argumentar sobre uma gama de aproximações teóricas entre Frege e Austin, este ensaio narra a importância da interpretação de Rajagopalan para o debate sobre Austin no Brasil.

  9. Natural cotton as precursor for the refractory boron carbide—a hydrothermal synthesis and characterization

    Science.gov (United States)

    Saritha Devi, H. V.; Swapna, M. S.; Raj, Vimal; Ambadas, G.; Sankararaman, S.

    2018-01-01

    Boron carbide (B4C) is an excellent covalent carbide that finds applications in industries and nuclear power plants. The present synthesis methods of boron carbide are expensive and involve the use of toxic chemicals that adversely affect environment. In the present work, we report for the first time the use of the hydrothermal method for converting the cellulose from cotton as the carbon precursor for B4C. The carbon precursor is converted into functionalized porous carbonaceous material by hydrothermal treatment followed by sodium borohydride. It is further treated with boric acid to make it a B4C precursor. The precursor is characterized by UV-visible diffuse reflectance, Raman, Fourier transform infrared, photoluminescent and energy dispersive spectroscopy. The morphology and structure analysis is carried out using field emission scanning electron microscopy and x-ray diffraction techniques. The results of structural and optical characterization of the sample synthesized are compared with the commercial B4C. The thermal stability of the sample is studied by thermogravimetric analysis. The sample annealed at 700 °C is found to be B4C devoid of amorphous carbon with a yield of 44.7%. The analysis reveals the formation of boron carbide from the sample.

  10. Social adaptability and substance abuse: Predictors of depression among hemodialysis patients?

    Science.gov (United States)

    2013-01-01

    Background Several aspects linked to social are involved in the onset of depressive feelings. We aimed to find out if social adaptability and substance abuse predict depression among end-stage renal disease (ESRD) patients undergoing hemodialysis (HD). Methods We included 145 ESRD patients undergoing HD. Social adaptability was estimated by the Social Adaptability Index (SAI). Substance abuse was defined according to SAI. We screened for depression by applying the 20-item version of the Center for Epidemiologic Studies Depression Scale. A score ≥ 24 classified the patients as depressed. Comparisons between depressed and non-depressed patients were carried out and logistic regression was performed to test gender, age, total SAI, SAI without the substance abuse item, only the substance abuse score and substance abuse as a categorical variable (yes/no) as predictors of depression. Results There were 36 (24.8%) depressed patients. There were no differences regarding demographic and laboratory data between the depressed and non-depressed patients. Mean SAI among depressed and non-depressed patients was, respectively, 6.1 ± 1.6 vs. 6.2 ± 1.9 (p=0.901). The percentage of patients with or without substance abuse among depressed patients was, respectively, 13.8% vs. 13.9% (p=1.000). Gender, age, total SAI, SAI without the substance abuse item, only the substance abuse score and substance abuse as a categorical variable did not predict depression. Conclusions Social adaptability and substance abuse did not predict depression in HD patients. We propose that aspects related to socioeconomic status not comprised in SAI items should be ruled out as predictors of depression. PMID:23320829

  11. Y2O3-MgO Nano-Composite Synthesized by Plasma Spraying and Thermal Decomposition of Solution Precursors

    Science.gov (United States)

    Muoto, Chigozie Kenechukwu

    This research aims to identify the key feedstock characteristics and processing conditions to produce Y2O3-MgO composite coatings with high density and hardness using solution precursor plasma spray (SPPS) and suspension plasma spray (SPS) processes, and also, to explore the phenomena involved in the production of homogenized nano-composite powders of this material system by thermal decomposition of solution precursor mixtures. The material system would find potential application in the fabrication of components for optical applications such as transparent windows. It was shown that a lack of major endothermic events during precursor decomposition and the resultant formation of highly dense particles upon pyrolysis are critical precursor characteristics for the deposition of dense and hard Y2O3-MgO coatings by SPPS. Using these principles, a new Y2O3-MgO precursor solution was developed, which yielded a coating with Vickers hardness of 560 Hv. This was a considerable improvement over the hardness of the coatings obtained using conventional solution precursors, which was as low as 110 Hv. In the thermal decomposition synthesis process, binary solution precursor mixtures of: yttrium nitrate (Y[n]) or yttrium acetate (Y[a]), with magnesium nitrate (Mg[n]) or magnesium acetate (Mg[a]) were used in order to study the effects of precursor chemistry on the structural characteristics of the resultant Y2O3-MgO powders. The phase domains were coarse and distributed rather inhomogeneously in the materials obtained from the Y[n]Mg[n] and Y[a]Mg[a] mixtures; finer and more homogeneously-distributed phase domains were obtained for ceramics produced from the Y[a]Mg[n] and Y[n]Mg[a] mixtures. It was established that these phenomena were related to the thermal characteristics for the decomposition of the precursors and their effect on phase separation during oxide crystallization. Addition of ammonium acetate to the Y[n[Mg[n] mixture changed the endothermic process to exothermic

  12. Orden de no reanimar, consideraciones sobre este problema

    Directory of Open Access Journals (Sweden)

    Dr. G. Luis Cereceda

    2011-05-01

    Se analizan los principales problemas, comenzando por las dificultades según los diferentes escenarios (servicio de urgencia, pabellón de maternidad, sala de hospitalizados, unidad de intensivo, pabellones quirúrgicos; se analiza la incertidumbre sobre el pronóstico de cada pacientes y sobre quién(es deben tomar las decisiones sobre el fin de la vida. Idealmente debe ser el paciente autónomo quien tome la decisión, pero en otros casos se requieren alternativas, una de ellas es la Orden Unilateral. Otros problemas son la Validez de las órdenes de no-RCP en los diferentes tiempos evolutivos, el problema de la Futilidad y la Validez de las “Directivas Anticipadas”, en este grupo resalta el enfoque POLST (Physician’s Order for Life Sustaining Treatment como más comprehensivo; como complemento ha surgido también el concepto AND (Allow Natural Death, que podría estar destinado a remplazar la orden de no-RCP (DNR.

  13. Sobre el Contenido de los Marcos Conceptuales Contables

    Directory of Open Access Journals (Sweden)

    Leila Di Russo de Hauque

    2007-12-01

    Full Text Available El presente trabajo tiene como objetivo el análisis de los distintos marcos conceptuales vigentes en diferentes sistemas normativos contables. Paralelamente a las revisiones empíricas que dicho trabajo determina, incluye reflexiones a priori sobre el contenido de dichos marcos conceptuales. El trabajo discurre inicialmente sobre el problema de la naturaleza normativa o doctrinaria de sus contenidos tradicionales sin inclinarse definitivamente por una u otra vertiente. Respecto de los elementos que se incluirán en ellos, se justifica la inclusión de las listas de objetivos y requisitos de la información contable para definir el alcance del concepto de informe de uso externo. Además se define a favor de la inclusión, conjuntamente con las respuestas a las pregunas básicas sobre la labor contable, de contenidos ligados al proceso de obtención y de la exposición de la información contable de uso externo.

  14. Uma Reflexão sobre Autoria Acadêmica

    Directory of Open Access Journals (Sweden)

    Francisco José da Costa

    2017-06-01

    Full Text Available Este estudo tem como objetivo apresentar elementos para um debate sobre a ética das práticas de autoria no campo científico brasileiro. Os autores utilizam exemplos ilustrativos para explorar as práticas de pseudoautoria, estabelecendo relações entre essas práticas, as coerções oriundas do campo acadêmico e o habitus dos agentes sociais. Foi elaborada uma definição preliminar do que seja autoria a fim de possibilitar a discussão sobre dois problemas centrais, que são: a lógica de “colocar o nome” e o plágio. Uma das principais contribuições deste trabalho repousa na reflexão orientada para a construção de uma prática aperfeiçoada de autoria, possibilitando a crítica e a autocrítica dos agentes do meio acadêmico sobre algumas práticas problemáticas de autoria.

  15. Hegel sobre Tácito y la libertad teutona

    Directory of Open Access Journals (Sweden)

    Valerio Rocco Lozano

    2015-09-01

    Full Text Available Una investigación sobre la presencia (así como sobre la ausencia de Tácito en Hegel es crucial para entender la posición política y filosófica de este pensador, especialmente en la época de Jena. Tras algunas consideraciones sobre el conocimiento hegeliano de la historia y la cultura romanas, se abordará un análisis de su noción de "libertad teutona": Hegel se opone tanto a la neo-romanidad de los revolucionarios franceses como al esencialismo teutómano de los conservadores alemanes (derivado fundamentalmente de un uso fuertemente ideológico de la "Germania" de Tácito, así como a las caducas instituciones imperiales. Esta doble oposición sitúa a Hegel en medio de dos corrientes políticas (e incluso de dos ejércitos en guerra y se lleva a cabo desde una actitud que puede denominarse como “mediación sin nostalgia”

  16. Characterization of soluble microbial products as precursors of disinfection byproducts in drinking water supply.

    Science.gov (United States)

    Liu, Jin-Lin; Li, Xiao-Yan; Xie, Yue-Feng; Tang, Hao

    2014-02-15

    Water pollution by wastewater discharge can cause the problem of disinfection byproducts (DBPs) in drinking water supply. In this study, DBP formation characteristics of soluble microbial products (SMPs) as the main products of wastewater organic biodegradation were investigated. The results show that SMPs can act as DBP precursors in simulated wastewater biodegradation process. Under the experimental conditions, stabilized SMPs had DBPFP (DBP formation potential) yield of around 5.6 μmol mmol(-1)-DOC (dissolved organic carbon) and DBP speciation profile different from that of the conventional precursor, natural organic matter (NOM). SMPs contained polysaccharides, proteins, and humic-like substances, and the latter two groups can act as reactive DBP precursors. SMP fraction with molecular weight of water treatment processes, more efforts are needed to control wastewater-derived DBP problem in water resource management. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Possibility to study ionospheric earthquakes precursors using CubeSats

    Science.gov (United States)

    Korepanov, Valery; Lappas, Vaios

    It is generally accepted that the earthquakes (EQ) are the most dangerous natural phenomena leading to the multiple losses in human lives and economics. The space observations must be included into the global chain of the EQ precursors monitoring at least as the initial warning to pay greater attention to the ground segment data. As the common opinion agrees, only in combination of multiple observation sites and set of monitored parameters the further progress at the way to raise EQ precursors detection probability may be obtained. There is necessary to answer two important questions before to plan any experiment to study ionospheric precursors of EQ. First one - whether the variations in the ionosphere definitely connected with the EQ preparation process do exist, and the second one - if they do, whether using these signals the precursors of EQ can be reliably identified and used for, if not prediction, then for the warning that the EQ in the given area approaches. The first successful mission dedicated to this problem solution was DEMETER (in orbit during more than 6 years from June 2004 until December 2010). The statistics of this study is impressive: altogether, about 9000 EQs with magnitude larger than M = 5.0 and depth lower than 40 km occurred all over the world during the analyzed period. In the result, the conclusion made there suggests that, obviously, there are real perturbations in the ionosphere connected with the seismic activity, but they are rather weak and at the present stage of data processing may be revealed only with the help of statistical analysis. To realize the study of ionospheric precursors, first it is imperative to clarify the mechanism of energy transfer along the chain “lithosphere-atmosphere-ionosphere”. Many hypotheses of such a mechanism exist, from which the mostly supported are fair weather currents (FWC) and atmospheric gravity waves (AGW), both of which have their pros and contras. The following minimal set of physical

  18. Reduced Prefrontal Short—Latency Afferent Inhibition in Older Adults and Its Relation to Executive Function: A TMS-EEG Study

    Directory of Open Access Journals (Sweden)

    Daniel M. Blumberger

    2017-05-01

    Full Text Available Combining transcranial magnetic stimulation (TMS with electroencephalography (EEG allows for the assessment of various neurophysiological processes in the human cortex. One of these paradigms, short-latency afferent inhibition (SAI, is thought to be a sensitive measure of cholinergic activity. In a previous study, we demonstrated the temporal pattern of this paradigm from both the motor (M1 and dorsolateral prefrontal cortex (DLPFC using simultaneous TMS–EEG recording. The SAI paradigm led to marked modulations at N100. In this study, we aimed to investigate the age-related effects on TMS-evoked potentials (TEPs with the SAI from M1 and the DLPFC in younger (18–59 years old and older (≥60 years old participants. Older participants showed significantly lower N100 modulation in M1–SAI as well as DLPFC–SAI compared to the younger participants. Furthermore, the modulation of N100 by DLPFC–SAI in the older participants correlated with executive function as measured with the Trail making test. This paradigm has the potential to non-invasively identify cholinergic changes in cortical regions related to cognition in older participants.

  19. Accident precursors, near misses, and warning signs: Critical review and formal definitions within the framework of Discrete Event Systems

    International Nuclear Information System (INIS)

    Saleh, Joseph H.; Saltmarsh, Elizabeth A.; Favarò, Francesca M.; Brevault, Loïc

    2013-01-01

    An important consideration in safety analysis and accident prevention is the identification of and response to accident precursors. These off-nominal events are opportunities to recognize potential accident pathogens, identify overlooked accident sequences, and make technical and organizational decisions to address them before further escalation can occur. When handled properly, the identification of precursors provides an opportunity to interrupt an accident sequence from unfolding; when ignored or missed, precursors may only provide tragic proof after the fact that an accident was preventable. In this work, we first provide a critical review of the concept of precursor, and we highlight important features that ought to be distinguished whenever accident precursors are discussed. We address for example the notion of ex-ante and ex-post precursors, identified for postulated and instantiated (occurred) accident sequences respectively, and we discuss the feature of transferability of precursors. We then develop a formal (mathematical) definition of accident precursors as truncated accident sequences within the modeling framework of Discrete Event Systems. Additionally, we examine the related notions of “accident pathogens” as static or lurking adverse conditions that can contribute to or aggravate an accident, as well as “near misses”, “warning signs” and the novel concept of “accident pathway”. While these terms are within the same linguistic neighborhood as “accident precursors”, we argue that there are subtle but important differences between them and recommend that they not be used interchangeably for the sake of accuracy and clarity of communication within the risk and safety community. We also propose venues for developing quantitative importance measures for accident precursors, similar to component importance measures in reliability engineering. Our objective is to establish a common understanding and clear delineation of these terms, and

  20. Precursors of the Forbush Decrease on 2006 December 14 Observed with the Global Muon Detector Network (GMDN)

    Science.gov (United States)

    Fushishita, A.; Kuwabara, T.; Kato, C.; Yasue, S.; Bieber, J. W.; Evenson, P.; Da Silva, M. R.; Dal Lago, A.; Schuch, N. J.; Tokumaru, M.; Duldig, M. L.; Humble, J. E.; Sabbah, I.; Jassar, H. K. Al; Sharma, M. M.; Munakata, K.

    2010-06-01

    We analyze the precursor of a Forbush decrease (FD) observed with the Global Muon Detector Network on 2006 December 14. An intense geomagnetic storm is also recorded during this FD with the peak Kp index of 8+. By using the "two-dimensional map" of the cosmic ray intensity produced after removing the contribution from the diurnal anisotropy, we succeed in extracting clear signatures of the precursor. A striking feature of this event is that a weak loss-cone (LC) signature is first recorded more than a day prior to the storm sudden commencement (SSC) onset. This suggests that the LC precursor appeared only 7 hr after the coronal mass ejection eruption from the Sun, when the interplanetary (IP) shock driven by the interplanetary coronal mass ejection was located at 0.4 AU from the Sun. We find the precursor being successively observed with multiple detectors in the network according to the Earth's spin and confirmed that the precursor continuously exists in space. The long lead time (15.6 hr) of this precursor which is almost twice the typical value indicates that the interplanetary magnetic field (IMF) was more quiet in this event than a typical power spectrum assumed for the IMF turbulence. The amplitude (-6.45%) of the LC anisotropy at the SSC onset is more than twice the FD size, indicating that the maximum intensity depression behind the IP shock is much larger than the FD size recorded at the Earth in this event. We also find the excess intensity from the sunward IMF direction clearly observed during ~10 hr preceding the SSC onset. It is shown that this excess intensity is consistent with the measurement of the particles accelerated by the head-on collisions with the approaching shock. This is the first detailed observation of the precursor due to the shock reflected particles with muon detectors.